1 /* Fold a constant sub-tree into a single node for C-compiler
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
4 2012 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /*@@ This file should be rewritten to use an arbitrary precision
23 @@ representation for "struct tree_int_cst" and "struct tree_real_cst".
24 @@ Perhaps the routines could also be used for bc/dc, and made a lib.
25 @@ The routines that translate from the ap rep should
26 @@ warn if precision et. al. is lost.
27 @@ This would also make life easier when this technology is used
28 @@ for cross-compilers. */
30 /* The entry points in this file are fold, size_int_wide and size_binop.
32 fold takes a tree as argument and returns a simplified tree.
34 size_binop takes a tree code for an arithmetic operation
35 and two operands that are trees, and produces a tree for the
36 result, assuming the type comes from `sizetype'.
38 size_int takes an integer value, and creates a tree constant
39 with type from `sizetype'.
41 Note: Since the folders get called on non-gimple code as well as
42 gimple code, we need to handle GIMPLE tuples as well as their
43 corresponding tree equivalents. */
47 #include "coretypes.h"
56 #include "diagnostic-core.h"
60 #include "langhooks.h"
63 #include "tree-flow.h"
65 /* Nonzero if we are folding constants inside an initializer; zero
67 int folding_initializer = 0;
69 /* The following constants represent a bit based encoding of GCC's
70 comparison operators. This encoding simplifies transformations
71 on relational comparison operators, such as AND and OR. */
72 enum comparison_code {
91 static bool negate_mathfn_p (enum built_in_function);
92 static bool negate_expr_p (tree);
93 static tree negate_expr (tree);
94 static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int);
95 static tree associate_trees (location_t, tree, tree, enum tree_code, tree);
96 static tree const_binop (enum tree_code, tree, tree);
97 static enum comparison_code comparison_to_compcode (enum tree_code);
98 static enum tree_code compcode_to_comparison (enum comparison_code);
99 static int operand_equal_for_comparison_p (tree, tree, tree);
100 static int twoval_comparison_p (tree, tree *, tree *, int *);
101 static tree eval_subst (location_t, tree, tree, tree, tree, tree);
102 static tree pedantic_omit_one_operand_loc (location_t, tree, tree, tree);
103 static tree distribute_bit_expr (location_t, enum tree_code, tree, tree, tree);
104 static tree make_bit_field_ref (location_t, tree, tree,
105 HOST_WIDE_INT, HOST_WIDE_INT, int);
106 static tree optimize_bit_field_compare (location_t, enum tree_code,
108 static tree decode_field_reference (location_t, tree, HOST_WIDE_INT *,
110 enum machine_mode *, int *, int *,
112 static int all_ones_mask_p (const_tree, int);
113 static tree sign_bit_p (tree, const_tree);
114 static int simple_operand_p (const_tree);
115 static bool simple_operand_p_2 (tree);
116 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
117 static tree range_predecessor (tree);
118 static tree range_successor (tree);
119 static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
120 static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
121 static tree unextend (tree, int, int, tree);
122 static tree optimize_minmax_comparison (location_t, enum tree_code,
124 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
125 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
126 static tree fold_binary_op_with_conditional_arg (location_t,
127 enum tree_code, tree,
130 static tree fold_mathfn_compare (location_t,
131 enum built_in_function, enum tree_code,
133 static tree fold_inf_compare (location_t, enum tree_code, tree, tree, tree);
134 static tree fold_div_compare (location_t, enum tree_code, tree, tree, tree);
135 static bool reorder_operands_p (const_tree, const_tree);
136 static tree fold_negate_const (tree, tree);
137 static tree fold_not_const (const_tree, tree);
138 static tree fold_relational_const (enum tree_code, tree, tree, tree);
139 static tree fold_convert_const (enum tree_code, tree, tree);
141 /* Return EXPR_LOCATION of T if it is not UNKNOWN_LOCATION.
142 Otherwise, return LOC. */
145 expr_location_or (tree t, location_t loc)
147 location_t tloc = EXPR_LOCATION (t);
148 return tloc != UNKNOWN_LOCATION ? tloc : loc;
151 /* Similar to protected_set_expr_location, but never modify x in place,
152 if location can and needs to be set, unshare it. */
155 protected_set_expr_location_unshare (tree x, location_t loc)
157 if (CAN_HAVE_LOCATION_P (x)
158 && EXPR_LOCATION (x) != loc
159 && !(TREE_CODE (x) == SAVE_EXPR
160 || TREE_CODE (x) == TARGET_EXPR
161 || TREE_CODE (x) == BIND_EXPR))
164 SET_EXPR_LOCATION (x, loc);
170 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
171 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
172 and SUM1. Then this yields nonzero if overflow occurred during the
175 Overflow occurs if A and B have the same sign, but A and SUM differ in
176 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
178 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
180 /* If ARG2 divides ARG1 with zero remainder, carries out the division
181 of type CODE and returns the quotient.
182 Otherwise returns NULL_TREE. */
185 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
190 /* The sign of the division is according to operand two, that
191 does the correct thing for POINTER_PLUS_EXPR where we want
192 a signed division. */
193 uns = TYPE_UNSIGNED (TREE_TYPE (arg2));
194 if (TREE_CODE (TREE_TYPE (arg2)) == INTEGER_TYPE
195 && TYPE_IS_SIZETYPE (TREE_TYPE (arg2)))
198 quo = double_int_divmod (tree_to_double_int (arg1),
199 tree_to_double_int (arg2),
202 if (double_int_zero_p (rem))
203 return build_int_cst_wide (TREE_TYPE (arg1), quo.low, quo.high);
208 /* This is nonzero if we should defer warnings about undefined
209 overflow. This facility exists because these warnings are a
210 special case. The code to estimate loop iterations does not want
211 to issue any warnings, since it works with expressions which do not
212 occur in user code. Various bits of cleanup code call fold(), but
213 only use the result if it has certain characteristics (e.g., is a
214 constant); that code only wants to issue a warning if the result is
217 static int fold_deferring_overflow_warnings;
219 /* If a warning about undefined overflow is deferred, this is the
220 warning. Note that this may cause us to turn two warnings into
221 one, but that is fine since it is sufficient to only give one
222 warning per expression. */
224 static const char* fold_deferred_overflow_warning;
226 /* If a warning about undefined overflow is deferred, this is the
227 level at which the warning should be emitted. */
229 static enum warn_strict_overflow_code fold_deferred_overflow_code;
231 /* Start deferring overflow warnings. We could use a stack here to
232 permit nested calls, but at present it is not necessary. */
235 fold_defer_overflow_warnings (void)
237 ++fold_deferring_overflow_warnings;
240 /* Stop deferring overflow warnings. If there is a pending warning,
241 and ISSUE is true, then issue the warning if appropriate. STMT is
242 the statement with which the warning should be associated (used for
243 location information); STMT may be NULL. CODE is the level of the
244 warning--a warn_strict_overflow_code value. This function will use
245 the smaller of CODE and the deferred code when deciding whether to
246 issue the warning. CODE may be zero to mean to always use the
250 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
255 gcc_assert (fold_deferring_overflow_warnings > 0);
256 --fold_deferring_overflow_warnings;
257 if (fold_deferring_overflow_warnings > 0)
259 if (fold_deferred_overflow_warning != NULL
261 && code < (int) fold_deferred_overflow_code)
262 fold_deferred_overflow_code = (enum warn_strict_overflow_code) code;
266 warnmsg = fold_deferred_overflow_warning;
267 fold_deferred_overflow_warning = NULL;
269 if (!issue || warnmsg == NULL)
272 if (gimple_no_warning_p (stmt))
275 /* Use the smallest code level when deciding to issue the
277 if (code == 0 || code > (int) fold_deferred_overflow_code)
278 code = fold_deferred_overflow_code;
280 if (!issue_strict_overflow_warning (code))
284 locus = input_location;
286 locus = gimple_location (stmt);
287 warning_at (locus, OPT_Wstrict_overflow, "%s", warnmsg);
290 /* Stop deferring overflow warnings, ignoring any deferred
294 fold_undefer_and_ignore_overflow_warnings (void)
296 fold_undefer_overflow_warnings (false, NULL, 0);
299 /* Whether we are deferring overflow warnings. */
302 fold_deferring_overflow_warnings_p (void)
304 return fold_deferring_overflow_warnings > 0;
307 /* This is called when we fold something based on the fact that signed
308 overflow is undefined. */
311 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
313 if (fold_deferring_overflow_warnings > 0)
315 if (fold_deferred_overflow_warning == NULL
316 || wc < fold_deferred_overflow_code)
318 fold_deferred_overflow_warning = gmsgid;
319 fold_deferred_overflow_code = wc;
322 else if (issue_strict_overflow_warning (wc))
323 warning (OPT_Wstrict_overflow, gmsgid);
326 /* Return true if the built-in mathematical function specified by CODE
327 is odd, i.e. -f(x) == f(-x). */
330 negate_mathfn_p (enum built_in_function code)
334 CASE_FLT_FN (BUILT_IN_ASIN):
335 CASE_FLT_FN (BUILT_IN_ASINH):
336 CASE_FLT_FN (BUILT_IN_ATAN):
337 CASE_FLT_FN (BUILT_IN_ATANH):
338 CASE_FLT_FN (BUILT_IN_CASIN):
339 CASE_FLT_FN (BUILT_IN_CASINH):
340 CASE_FLT_FN (BUILT_IN_CATAN):
341 CASE_FLT_FN (BUILT_IN_CATANH):
342 CASE_FLT_FN (BUILT_IN_CBRT):
343 CASE_FLT_FN (BUILT_IN_CPROJ):
344 CASE_FLT_FN (BUILT_IN_CSIN):
345 CASE_FLT_FN (BUILT_IN_CSINH):
346 CASE_FLT_FN (BUILT_IN_CTAN):
347 CASE_FLT_FN (BUILT_IN_CTANH):
348 CASE_FLT_FN (BUILT_IN_ERF):
349 CASE_FLT_FN (BUILT_IN_LLROUND):
350 CASE_FLT_FN (BUILT_IN_LROUND):
351 CASE_FLT_FN (BUILT_IN_ROUND):
352 CASE_FLT_FN (BUILT_IN_SIN):
353 CASE_FLT_FN (BUILT_IN_SINH):
354 CASE_FLT_FN (BUILT_IN_TAN):
355 CASE_FLT_FN (BUILT_IN_TANH):
356 CASE_FLT_FN (BUILT_IN_TRUNC):
359 CASE_FLT_FN (BUILT_IN_LLRINT):
360 CASE_FLT_FN (BUILT_IN_LRINT):
361 CASE_FLT_FN (BUILT_IN_NEARBYINT):
362 CASE_FLT_FN (BUILT_IN_RINT):
363 return !flag_rounding_math;
371 /* Check whether we may negate an integer constant T without causing
375 may_negate_without_overflow_p (const_tree t)
377 unsigned HOST_WIDE_INT val;
381 gcc_assert (TREE_CODE (t) == INTEGER_CST);
383 type = TREE_TYPE (t);
384 if (TYPE_UNSIGNED (type))
387 prec = TYPE_PRECISION (type);
388 if (prec > HOST_BITS_PER_WIDE_INT)
390 if (TREE_INT_CST_LOW (t) != 0)
392 prec -= HOST_BITS_PER_WIDE_INT;
393 val = TREE_INT_CST_HIGH (t);
396 val = TREE_INT_CST_LOW (t);
397 if (prec < HOST_BITS_PER_WIDE_INT)
398 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
399 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
402 /* Determine whether an expression T can be cheaply negated using
403 the function negate_expr without introducing undefined overflow. */
406 negate_expr_p (tree t)
413 type = TREE_TYPE (t);
416 switch (TREE_CODE (t))
419 if (TYPE_OVERFLOW_WRAPS (type))
422 /* Check that -CST will not overflow type. */
423 return may_negate_without_overflow_p (t);
425 return (INTEGRAL_TYPE_P (type)
426 && TYPE_OVERFLOW_WRAPS (type));
433 /* We want to canonicalize to positive real constants. Pretend
434 that only negative ones can be easily negated. */
435 return REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
438 return negate_expr_p (TREE_REALPART (t))
439 && negate_expr_p (TREE_IMAGPART (t));
442 return negate_expr_p (TREE_OPERAND (t, 0))
443 && negate_expr_p (TREE_OPERAND (t, 1));
446 return negate_expr_p (TREE_OPERAND (t, 0));
449 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
450 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
452 /* -(A + B) -> (-B) - A. */
453 if (negate_expr_p (TREE_OPERAND (t, 1))
454 && reorder_operands_p (TREE_OPERAND (t, 0),
455 TREE_OPERAND (t, 1)))
457 /* -(A + B) -> (-A) - B. */
458 return negate_expr_p (TREE_OPERAND (t, 0));
461 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
462 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
463 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
464 && reorder_operands_p (TREE_OPERAND (t, 0),
465 TREE_OPERAND (t, 1));
468 if (TYPE_UNSIGNED (TREE_TYPE (t)))
474 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
475 return negate_expr_p (TREE_OPERAND (t, 1))
476 || negate_expr_p (TREE_OPERAND (t, 0));
484 /* In general we can't negate A / B, because if A is INT_MIN and
485 B is 1, we may turn this into INT_MIN / -1 which is undefined
486 and actually traps on some architectures. But if overflow is
487 undefined, we can negate, because - (INT_MIN / 1) is an
489 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
490 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
492 return negate_expr_p (TREE_OPERAND (t, 1))
493 || negate_expr_p (TREE_OPERAND (t, 0));
496 /* Negate -((double)float) as (double)(-float). */
497 if (TREE_CODE (type) == REAL_TYPE)
499 tree tem = strip_float_extensions (t);
501 return negate_expr_p (tem);
506 /* Negate -f(x) as f(-x). */
507 if (negate_mathfn_p (builtin_mathfn_code (t)))
508 return negate_expr_p (CALL_EXPR_ARG (t, 0));
512 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
513 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
515 tree op1 = TREE_OPERAND (t, 1);
516 if (TREE_INT_CST_HIGH (op1) == 0
517 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
518 == TREE_INT_CST_LOW (op1))
529 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
530 simplification is possible.
531 If negate_expr_p would return true for T, NULL_TREE will never be
535 fold_negate_expr (location_t loc, tree t)
537 tree type = TREE_TYPE (t);
540 switch (TREE_CODE (t))
542 /* Convert - (~A) to A + 1. */
544 if (INTEGRAL_TYPE_P (type))
545 return fold_build2_loc (loc, PLUS_EXPR, type, TREE_OPERAND (t, 0),
546 build_int_cst (type, 1));
550 tem = fold_negate_const (t, type);
551 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
552 || !TYPE_OVERFLOW_TRAPS (type))
557 tem = fold_negate_const (t, type);
558 /* Two's complement FP formats, such as c4x, may overflow. */
559 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
564 tem = fold_negate_const (t, type);
569 tree rpart = negate_expr (TREE_REALPART (t));
570 tree ipart = negate_expr (TREE_IMAGPART (t));
572 if ((TREE_CODE (rpart) == REAL_CST
573 && TREE_CODE (ipart) == REAL_CST)
574 || (TREE_CODE (rpart) == INTEGER_CST
575 && TREE_CODE (ipart) == INTEGER_CST))
576 return build_complex (type, rpart, ipart);
581 if (negate_expr_p (t))
582 return fold_build2_loc (loc, COMPLEX_EXPR, type,
583 fold_negate_expr (loc, TREE_OPERAND (t, 0)),
584 fold_negate_expr (loc, TREE_OPERAND (t, 1)));
588 if (negate_expr_p (t))
589 return fold_build1_loc (loc, CONJ_EXPR, type,
590 fold_negate_expr (loc, TREE_OPERAND (t, 0)));
594 return TREE_OPERAND (t, 0);
597 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
598 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
600 /* -(A + B) -> (-B) - A. */
601 if (negate_expr_p (TREE_OPERAND (t, 1))
602 && reorder_operands_p (TREE_OPERAND (t, 0),
603 TREE_OPERAND (t, 1)))
605 tem = negate_expr (TREE_OPERAND (t, 1));
606 return fold_build2_loc (loc, MINUS_EXPR, type,
607 tem, TREE_OPERAND (t, 0));
610 /* -(A + B) -> (-A) - B. */
611 if (negate_expr_p (TREE_OPERAND (t, 0)))
613 tem = negate_expr (TREE_OPERAND (t, 0));
614 return fold_build2_loc (loc, MINUS_EXPR, type,
615 tem, TREE_OPERAND (t, 1));
621 /* - (A - B) -> B - A */
622 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
623 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
624 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
625 return fold_build2_loc (loc, MINUS_EXPR, type,
626 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
630 if (TYPE_UNSIGNED (type))
636 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
638 tem = TREE_OPERAND (t, 1);
639 if (negate_expr_p (tem))
640 return fold_build2_loc (loc, TREE_CODE (t), type,
641 TREE_OPERAND (t, 0), negate_expr (tem));
642 tem = TREE_OPERAND (t, 0);
643 if (negate_expr_p (tem))
644 return fold_build2_loc (loc, TREE_CODE (t), type,
645 negate_expr (tem), TREE_OPERAND (t, 1));
654 /* In general we can't negate A / B, because if A is INT_MIN and
655 B is 1, we may turn this into INT_MIN / -1 which is undefined
656 and actually traps on some architectures. But if overflow is
657 undefined, we can negate, because - (INT_MIN / 1) is an
659 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
661 const char * const warnmsg = G_("assuming signed overflow does not "
662 "occur when negating a division");
663 tem = TREE_OPERAND (t, 1);
664 if (negate_expr_p (tem))
666 if (INTEGRAL_TYPE_P (type)
667 && (TREE_CODE (tem) != INTEGER_CST
668 || integer_onep (tem)))
669 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
670 return fold_build2_loc (loc, TREE_CODE (t), type,
671 TREE_OPERAND (t, 0), negate_expr (tem));
673 tem = TREE_OPERAND (t, 0);
674 if (negate_expr_p (tem))
676 if (INTEGRAL_TYPE_P (type)
677 && (TREE_CODE (tem) != INTEGER_CST
678 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
679 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
680 return fold_build2_loc (loc, TREE_CODE (t), type,
681 negate_expr (tem), TREE_OPERAND (t, 1));
687 /* Convert -((double)float) into (double)(-float). */
688 if (TREE_CODE (type) == REAL_TYPE)
690 tem = strip_float_extensions (t);
691 if (tem != t && negate_expr_p (tem))
692 return fold_convert_loc (loc, type, negate_expr (tem));
697 /* Negate -f(x) as f(-x). */
698 if (negate_mathfn_p (builtin_mathfn_code (t))
699 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
703 fndecl = get_callee_fndecl (t);
704 arg = negate_expr (CALL_EXPR_ARG (t, 0));
705 return build_call_expr_loc (loc, fndecl, 1, arg);
710 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
711 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
713 tree op1 = TREE_OPERAND (t, 1);
714 if (TREE_INT_CST_HIGH (op1) == 0
715 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
716 == TREE_INT_CST_LOW (op1))
718 tree ntype = TYPE_UNSIGNED (type)
719 ? signed_type_for (type)
720 : unsigned_type_for (type);
721 tree temp = fold_convert_loc (loc, ntype, TREE_OPERAND (t, 0));
722 temp = fold_build2_loc (loc, RSHIFT_EXPR, ntype, temp, op1);
723 return fold_convert_loc (loc, type, temp);
735 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
736 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
748 loc = EXPR_LOCATION (t);
749 type = TREE_TYPE (t);
752 tem = fold_negate_expr (loc, t);
754 tem = build1_loc (loc, NEGATE_EXPR, TREE_TYPE (t), t);
755 return fold_convert_loc (loc, type, tem);
758 /* Split a tree IN into a constant, literal and variable parts that could be
759 combined with CODE to make IN. "constant" means an expression with
760 TREE_CONSTANT but that isn't an actual constant. CODE must be a
761 commutative arithmetic operation. Store the constant part into *CONP,
762 the literal in *LITP and return the variable part. If a part isn't
763 present, set it to null. If the tree does not decompose in this way,
764 return the entire tree as the variable part and the other parts as null.
766 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
767 case, we negate an operand that was subtracted. Except if it is a
768 literal for which we use *MINUS_LITP instead.
770 If NEGATE_P is true, we are negating all of IN, again except a literal
771 for which we use *MINUS_LITP instead.
773 If IN is itself a literal or constant, return it as appropriate.
775 Note that we do not guarantee that any of the three values will be the
776 same type as IN, but they will have the same signedness and mode. */
779 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
780 tree *minus_litp, int negate_p)
788 /* Strip any conversions that don't change the machine mode or signedness. */
789 STRIP_SIGN_NOPS (in);
791 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
792 || TREE_CODE (in) == FIXED_CST)
794 else if (TREE_CODE (in) == code
795 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
796 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
797 /* We can associate addition and subtraction together (even
798 though the C standard doesn't say so) for integers because
799 the value is not affected. For reals, the value might be
800 affected, so we can't. */
801 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
802 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
804 tree op0 = TREE_OPERAND (in, 0);
805 tree op1 = TREE_OPERAND (in, 1);
806 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
807 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
809 /* First see if either of the operands is a literal, then a constant. */
810 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
811 || TREE_CODE (op0) == FIXED_CST)
812 *litp = op0, op0 = 0;
813 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
814 || TREE_CODE (op1) == FIXED_CST)
815 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
817 if (op0 != 0 && TREE_CONSTANT (op0))
818 *conp = op0, op0 = 0;
819 else if (op1 != 0 && TREE_CONSTANT (op1))
820 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
822 /* If we haven't dealt with either operand, this is not a case we can
823 decompose. Otherwise, VAR is either of the ones remaining, if any. */
824 if (op0 != 0 && op1 != 0)
829 var = op1, neg_var_p = neg1_p;
831 /* Now do any needed negations. */
833 *minus_litp = *litp, *litp = 0;
835 *conp = negate_expr (*conp);
837 var = negate_expr (var);
839 else if (TREE_CONSTANT (in))
847 *minus_litp = *litp, *litp = 0;
848 else if (*minus_litp)
849 *litp = *minus_litp, *minus_litp = 0;
850 *conp = negate_expr (*conp);
851 var = negate_expr (var);
857 /* Re-associate trees split by the above function. T1 and T2 are
858 either expressions to associate or null. Return the new
859 expression, if any. LOC is the location of the new expression. If
860 we build an operation, do it in TYPE and with CODE. */
863 associate_trees (location_t loc, tree t1, tree t2, enum tree_code code, tree type)
870 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
871 try to fold this since we will have infinite recursion. But do
872 deal with any NEGATE_EXPRs. */
873 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
874 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
876 if (code == PLUS_EXPR)
878 if (TREE_CODE (t1) == NEGATE_EXPR)
879 return build2_loc (loc, MINUS_EXPR, type,
880 fold_convert_loc (loc, type, t2),
881 fold_convert_loc (loc, type,
882 TREE_OPERAND (t1, 0)));
883 else if (TREE_CODE (t2) == NEGATE_EXPR)
884 return build2_loc (loc, MINUS_EXPR, type,
885 fold_convert_loc (loc, type, t1),
886 fold_convert_loc (loc, type,
887 TREE_OPERAND (t2, 0)));
888 else if (integer_zerop (t2))
889 return fold_convert_loc (loc, type, t1);
891 else if (code == MINUS_EXPR)
893 if (integer_zerop (t2))
894 return fold_convert_loc (loc, type, t1);
897 return build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
898 fold_convert_loc (loc, type, t2));
901 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
902 fold_convert_loc (loc, type, t2));
905 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
906 for use in int_const_binop, size_binop and size_diffop. */
909 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
911 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
913 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
928 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
929 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
930 && TYPE_MODE (type1) == TYPE_MODE (type2);
934 /* Combine two integer constants ARG1 and ARG2 under operation CODE
935 to produce a new constant. Return NULL_TREE if we don't know how
936 to evaluate CODE at compile-time. */
939 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2)
941 double_int op1, op2, res, tmp;
943 tree type = TREE_TYPE (arg1);
944 bool uns = TYPE_UNSIGNED (type);
946 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
947 bool overflow = false;
949 op1 = tree_to_double_int (arg1);
950 op2 = tree_to_double_int (arg2);
955 res = double_int_ior (op1, op2);
959 res = double_int_xor (op1, op2);
963 res = double_int_and (op1, op2);
967 res = double_int_rshift (op1, double_int_to_shwi (op2),
968 TYPE_PRECISION (type), !uns);
972 /* It's unclear from the C standard whether shifts can overflow.
973 The following code ignores overflow; perhaps a C standard
974 interpretation ruling is needed. */
975 res = double_int_lshift (op1, double_int_to_shwi (op2),
976 TYPE_PRECISION (type), !uns);
980 res = double_int_rrotate (op1, double_int_to_shwi (op2),
981 TYPE_PRECISION (type));
985 res = double_int_lrotate (op1, double_int_to_shwi (op2),
986 TYPE_PRECISION (type));
990 overflow = add_double (op1.low, op1.high, op2.low, op2.high,
991 &res.low, &res.high);
995 neg_double (op2.low, op2.high, &res.low, &res.high);
996 add_double (op1.low, op1.high, res.low, res.high,
997 &res.low, &res.high);
998 overflow = OVERFLOW_SUM_SIGN (res.high, op2.high, op1.high);
1002 overflow = mul_double (op1.low, op1.high, op2.low, op2.high,
1003 &res.low, &res.high);
1006 case TRUNC_DIV_EXPR:
1007 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1008 case EXACT_DIV_EXPR:
1009 /* This is a shortcut for a common special case. */
1010 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
1011 && !TREE_OVERFLOW (arg1)
1012 && !TREE_OVERFLOW (arg2)
1013 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
1015 if (code == CEIL_DIV_EXPR)
1016 op1.low += op2.low - 1;
1018 res.low = op1.low / op2.low, res.high = 0;
1022 /* ... fall through ... */
1024 case ROUND_DIV_EXPR:
1025 if (double_int_zero_p (op2))
1027 if (double_int_one_p (op2))
1032 if (double_int_equal_p (op1, op2)
1033 && ! double_int_zero_p (op1))
1035 res = double_int_one;
1038 overflow = div_and_round_double (code, uns,
1039 op1.low, op1.high, op2.low, op2.high,
1040 &res.low, &res.high,
1041 &tmp.low, &tmp.high);
1044 case TRUNC_MOD_EXPR:
1045 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1046 /* This is a shortcut for a common special case. */
1047 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
1048 && !TREE_OVERFLOW (arg1)
1049 && !TREE_OVERFLOW (arg2)
1050 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
1052 if (code == CEIL_MOD_EXPR)
1053 op1.low += op2.low - 1;
1054 res.low = op1.low % op2.low, res.high = 0;
1058 /* ... fall through ... */
1060 case ROUND_MOD_EXPR:
1061 if (double_int_zero_p (op2))
1063 overflow = div_and_round_double (code, uns,
1064 op1.low, op1.high, op2.low, op2.high,
1065 &tmp.low, &tmp.high,
1066 &res.low, &res.high);
1070 res = double_int_min (op1, op2, uns);
1074 res = double_int_max (op1, op2, uns);
1081 t = force_fit_type_double (TREE_TYPE (arg1), res, 1,
1082 ((!uns || is_sizetype) && overflow)
1083 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1088 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1089 constant. We assume ARG1 and ARG2 have the same data type, or at least
1090 are the same kind of constant and the same machine mode. Return zero if
1091 combining the constants is not allowed in the current operating mode. */
1094 const_binop (enum tree_code code, tree arg1, tree arg2)
1096 /* Sanity check for the recursive cases. */
1103 if (TREE_CODE (arg1) == INTEGER_CST)
1104 return int_const_binop (code, arg1, arg2);
1106 if (TREE_CODE (arg1) == REAL_CST)
1108 enum machine_mode mode;
1111 REAL_VALUE_TYPE value;
1112 REAL_VALUE_TYPE result;
1116 /* The following codes are handled by real_arithmetic. */
1131 d1 = TREE_REAL_CST (arg1);
1132 d2 = TREE_REAL_CST (arg2);
1134 type = TREE_TYPE (arg1);
1135 mode = TYPE_MODE (type);
1137 /* Don't perform operation if we honor signaling NaNs and
1138 either operand is a NaN. */
1139 if (HONOR_SNANS (mode)
1140 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1143 /* Don't perform operation if it would raise a division
1144 by zero exception. */
1145 if (code == RDIV_EXPR
1146 && REAL_VALUES_EQUAL (d2, dconst0)
1147 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1150 /* If either operand is a NaN, just return it. Otherwise, set up
1151 for floating-point trap; we return an overflow. */
1152 if (REAL_VALUE_ISNAN (d1))
1154 else if (REAL_VALUE_ISNAN (d2))
1157 inexact = real_arithmetic (&value, code, &d1, &d2);
1158 real_convert (&result, mode, &value);
1160 /* Don't constant fold this floating point operation if
1161 the result has overflowed and flag_trapping_math. */
1162 if (flag_trapping_math
1163 && MODE_HAS_INFINITIES (mode)
1164 && REAL_VALUE_ISINF (result)
1165 && !REAL_VALUE_ISINF (d1)
1166 && !REAL_VALUE_ISINF (d2))
1169 /* Don't constant fold this floating point operation if the
1170 result may dependent upon the run-time rounding mode and
1171 flag_rounding_math is set, or if GCC's software emulation
1172 is unable to accurately represent the result. */
1173 if ((flag_rounding_math
1174 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1175 && (inexact || !real_identical (&result, &value)))
1178 t = build_real (type, result);
1180 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1184 if (TREE_CODE (arg1) == FIXED_CST)
1186 FIXED_VALUE_TYPE f1;
1187 FIXED_VALUE_TYPE f2;
1188 FIXED_VALUE_TYPE result;
1193 /* The following codes are handled by fixed_arithmetic. */
1199 case TRUNC_DIV_EXPR:
1200 f2 = TREE_FIXED_CST (arg2);
1205 f2.data.high = TREE_INT_CST_HIGH (arg2);
1206 f2.data.low = TREE_INT_CST_LOW (arg2);
1214 f1 = TREE_FIXED_CST (arg1);
1215 type = TREE_TYPE (arg1);
1216 sat_p = TYPE_SATURATING (type);
1217 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1218 t = build_fixed (type, result);
1219 /* Propagate overflow flags. */
1220 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1221 TREE_OVERFLOW (t) = 1;
1225 if (TREE_CODE (arg1) == COMPLEX_CST)
1227 tree type = TREE_TYPE (arg1);
1228 tree r1 = TREE_REALPART (arg1);
1229 tree i1 = TREE_IMAGPART (arg1);
1230 tree r2 = TREE_REALPART (arg2);
1231 tree i2 = TREE_IMAGPART (arg2);
1238 real = const_binop (code, r1, r2);
1239 imag = const_binop (code, i1, i2);
1243 if (COMPLEX_FLOAT_TYPE_P (type))
1244 return do_mpc_arg2 (arg1, arg2, type,
1245 /* do_nonfinite= */ folding_initializer,
1248 real = const_binop (MINUS_EXPR,
1249 const_binop (MULT_EXPR, r1, r2),
1250 const_binop (MULT_EXPR, i1, i2));
1251 imag = const_binop (PLUS_EXPR,
1252 const_binop (MULT_EXPR, r1, i2),
1253 const_binop (MULT_EXPR, i1, r2));
1257 if (COMPLEX_FLOAT_TYPE_P (type))
1258 return do_mpc_arg2 (arg1, arg2, type,
1259 /* do_nonfinite= */ folding_initializer,
1262 case TRUNC_DIV_EXPR:
1264 case FLOOR_DIV_EXPR:
1265 case ROUND_DIV_EXPR:
1266 if (flag_complex_method == 0)
1268 /* Keep this algorithm in sync with
1269 tree-complex.c:expand_complex_div_straight().
1271 Expand complex division to scalars, straightforward algorithm.
1272 a / b = ((ar*br + ai*bi)/t) + i((ai*br - ar*bi)/t)
1276 = const_binop (PLUS_EXPR,
1277 const_binop (MULT_EXPR, r2, r2),
1278 const_binop (MULT_EXPR, i2, i2));
1280 = const_binop (PLUS_EXPR,
1281 const_binop (MULT_EXPR, r1, r2),
1282 const_binop (MULT_EXPR, i1, i2));
1284 = const_binop (MINUS_EXPR,
1285 const_binop (MULT_EXPR, i1, r2),
1286 const_binop (MULT_EXPR, r1, i2));
1288 real = const_binop (code, t1, magsquared);
1289 imag = const_binop (code, t2, magsquared);
1293 /* Keep this algorithm in sync with
1294 tree-complex.c:expand_complex_div_wide().
1296 Expand complex division to scalars, modified algorithm to minimize
1297 overflow with wide input ranges. */
1298 tree compare = fold_build2 (LT_EXPR, boolean_type_node,
1299 fold_abs_const (r2, TREE_TYPE (type)),
1300 fold_abs_const (i2, TREE_TYPE (type)));
1302 if (integer_nonzerop (compare))
1304 /* In the TRUE branch, we compute
1306 div = (br * ratio) + bi;
1307 tr = (ar * ratio) + ai;
1308 ti = (ai * ratio) - ar;
1311 tree ratio = const_binop (code, r2, i2);
1312 tree div = const_binop (PLUS_EXPR, i2,
1313 const_binop (MULT_EXPR, r2, ratio));
1314 real = const_binop (MULT_EXPR, r1, ratio);
1315 real = const_binop (PLUS_EXPR, real, i1);
1316 real = const_binop (code, real, div);
1318 imag = const_binop (MULT_EXPR, i1, ratio);
1319 imag = const_binop (MINUS_EXPR, imag, r1);
1320 imag = const_binop (code, imag, div);
1324 /* In the FALSE branch, we compute
1326 divisor = (d * ratio) + c;
1327 tr = (b * ratio) + a;
1328 ti = b - (a * ratio);
1331 tree ratio = const_binop (code, i2, r2);
1332 tree div = const_binop (PLUS_EXPR, r2,
1333 const_binop (MULT_EXPR, i2, ratio));
1335 real = const_binop (MULT_EXPR, i1, ratio);
1336 real = const_binop (PLUS_EXPR, real, r1);
1337 real = const_binop (code, real, div);
1339 imag = const_binop (MULT_EXPR, r1, ratio);
1340 imag = const_binop (MINUS_EXPR, i1, imag);
1341 imag = const_binop (code, imag, div);
1351 return build_complex (type, real, imag);
1354 if (TREE_CODE (arg1) == VECTOR_CST)
1356 tree type = TREE_TYPE(arg1);
1357 int count = TYPE_VECTOR_SUBPARTS (type), i;
1358 tree elements1, elements2, list = NULL_TREE;
1360 if(TREE_CODE(arg2) != VECTOR_CST)
1363 elements1 = TREE_VECTOR_CST_ELTS (arg1);
1364 elements2 = TREE_VECTOR_CST_ELTS (arg2);
1366 for (i = 0; i < count; i++)
1368 tree elem1, elem2, elem;
1370 /* The trailing elements can be empty and should be treated as 0 */
1372 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1375 elem1 = TREE_VALUE(elements1);
1376 elements1 = TREE_CHAIN (elements1);
1380 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1383 elem2 = TREE_VALUE(elements2);
1384 elements2 = TREE_CHAIN (elements2);
1387 elem = const_binop (code, elem1, elem2);
1389 /* It is possible that const_binop cannot handle the given
1390 code and return NULL_TREE */
1391 if(elem == NULL_TREE)
1394 list = tree_cons (NULL_TREE, elem, list);
1396 return build_vector(type, nreverse(list));
1401 /* Create a size type INT_CST node with NUMBER sign extended. KIND
1402 indicates which particular sizetype to create. */
1405 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
1407 return build_int_cst (sizetype_tab[(int) kind], number);
1410 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
1411 is a tree code. The type of the result is taken from the operands.
1412 Both must be equivalent integer types, ala int_binop_types_match_p.
1413 If the operands are constant, so is the result. */
1416 size_binop_loc (location_t loc, enum tree_code code, tree arg0, tree arg1)
1418 tree type = TREE_TYPE (arg0);
1420 if (arg0 == error_mark_node || arg1 == error_mark_node)
1421 return error_mark_node;
1423 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
1426 /* Handle the special case of two integer constants faster. */
1427 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
1429 /* And some specific cases even faster than that. */
1430 if (code == PLUS_EXPR)
1432 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
1434 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1437 else if (code == MINUS_EXPR)
1439 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1442 else if (code == MULT_EXPR)
1444 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
1448 /* Handle general case of two integer constants. */
1449 return int_const_binop (code, arg0, arg1);
1452 return fold_build2_loc (loc, code, type, arg0, arg1);
1455 /* Given two values, either both of sizetype or both of bitsizetype,
1456 compute the difference between the two values. Return the value
1457 in signed type corresponding to the type of the operands. */
1460 size_diffop_loc (location_t loc, tree arg0, tree arg1)
1462 tree type = TREE_TYPE (arg0);
1465 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
1468 /* If the type is already signed, just do the simple thing. */
1469 if (!TYPE_UNSIGNED (type))
1470 return size_binop_loc (loc, MINUS_EXPR, arg0, arg1);
1472 if (type == sizetype)
1474 else if (type == bitsizetype)
1475 ctype = sbitsizetype;
1477 ctype = signed_type_for (type);
1479 /* If either operand is not a constant, do the conversions to the signed
1480 type and subtract. The hardware will do the right thing with any
1481 overflow in the subtraction. */
1482 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
1483 return size_binop_loc (loc, MINUS_EXPR,
1484 fold_convert_loc (loc, ctype, arg0),
1485 fold_convert_loc (loc, ctype, arg1));
1487 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
1488 Otherwise, subtract the other way, convert to CTYPE (we know that can't
1489 overflow) and negate (which can't either). Special-case a result
1490 of zero while we're here. */
1491 if (tree_int_cst_equal (arg0, arg1))
1492 return build_int_cst (ctype, 0);
1493 else if (tree_int_cst_lt (arg1, arg0))
1494 return fold_convert_loc (loc, ctype,
1495 size_binop_loc (loc, MINUS_EXPR, arg0, arg1));
1497 return size_binop_loc (loc, MINUS_EXPR, build_int_cst (ctype, 0),
1498 fold_convert_loc (loc, ctype,
1499 size_binop_loc (loc,
1504 /* A subroutine of fold_convert_const handling conversions of an
1505 INTEGER_CST to another integer type. */
1508 fold_convert_const_int_from_int (tree type, const_tree arg1)
1512 /* Given an integer constant, make new constant with new type,
1513 appropriately sign-extended or truncated. */
1514 t = force_fit_type_double (type, tree_to_double_int (arg1),
1515 !POINTER_TYPE_P (TREE_TYPE (arg1)),
1516 (TREE_INT_CST_HIGH (arg1) < 0
1517 && (TYPE_UNSIGNED (type)
1518 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1519 | TREE_OVERFLOW (arg1));
1524 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1525 to an integer type. */
1528 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
1533 /* The following code implements the floating point to integer
1534 conversion rules required by the Java Language Specification,
1535 that IEEE NaNs are mapped to zero and values that overflow
1536 the target precision saturate, i.e. values greater than
1537 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
1538 are mapped to INT_MIN. These semantics are allowed by the
1539 C and C++ standards that simply state that the behavior of
1540 FP-to-integer conversion is unspecified upon overflow. */
1544 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
1548 case FIX_TRUNC_EXPR:
1549 real_trunc (&r, VOIDmode, &x);
1556 /* If R is NaN, return zero and show we have an overflow. */
1557 if (REAL_VALUE_ISNAN (r))
1560 val = double_int_zero;
1563 /* See if R is less than the lower bound or greater than the
1568 tree lt = TYPE_MIN_VALUE (type);
1569 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
1570 if (REAL_VALUES_LESS (r, l))
1573 val = tree_to_double_int (lt);
1579 tree ut = TYPE_MAX_VALUE (type);
1582 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
1583 if (REAL_VALUES_LESS (u, r))
1586 val = tree_to_double_int (ut);
1592 real_to_integer2 ((HOST_WIDE_INT *) &val.low, &val.high, &r);
1594 t = force_fit_type_double (type, val, -1, overflow | TREE_OVERFLOW (arg1));
1598 /* A subroutine of fold_convert_const handling conversions of a
1599 FIXED_CST to an integer type. */
1602 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
1605 double_int temp, temp_trunc;
1608 /* Right shift FIXED_CST to temp by fbit. */
1609 temp = TREE_FIXED_CST (arg1).data;
1610 mode = TREE_FIXED_CST (arg1).mode;
1611 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
1613 temp = double_int_rshift (temp, GET_MODE_FBIT (mode),
1614 HOST_BITS_PER_DOUBLE_INT,
1615 SIGNED_FIXED_POINT_MODE_P (mode));
1617 /* Left shift temp to temp_trunc by fbit. */
1618 temp_trunc = double_int_lshift (temp, GET_MODE_FBIT (mode),
1619 HOST_BITS_PER_DOUBLE_INT,
1620 SIGNED_FIXED_POINT_MODE_P (mode));
1624 temp = double_int_zero;
1625 temp_trunc = double_int_zero;
1628 /* If FIXED_CST is negative, we need to round the value toward 0.
1629 By checking if the fractional bits are not zero to add 1 to temp. */
1630 if (SIGNED_FIXED_POINT_MODE_P (mode)
1631 && double_int_negative_p (temp_trunc)
1632 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
1633 temp = double_int_add (temp, double_int_one);
1635 /* Given a fixed-point constant, make new constant with new type,
1636 appropriately sign-extended or truncated. */
1637 t = force_fit_type_double (type, temp, -1,
1638 (double_int_negative_p (temp)
1639 && (TYPE_UNSIGNED (type)
1640 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1641 | TREE_OVERFLOW (arg1));
1646 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1647 to another floating point type. */
1650 fold_convert_const_real_from_real (tree type, const_tree arg1)
1652 REAL_VALUE_TYPE value;
1655 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
1656 t = build_real (type, value);
1658 /* If converting an infinity or NAN to a representation that doesn't
1659 have one, set the overflow bit so that we can produce some kind of
1660 error message at the appropriate point if necessary. It's not the
1661 most user-friendly message, but it's better than nothing. */
1662 if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1))
1663 && !MODE_HAS_INFINITIES (TYPE_MODE (type)))
1664 TREE_OVERFLOW (t) = 1;
1665 else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
1666 && !MODE_HAS_NANS (TYPE_MODE (type)))
1667 TREE_OVERFLOW (t) = 1;
1668 /* Regular overflow, conversion produced an infinity in a mode that
1669 can't represent them. */
1670 else if (!MODE_HAS_INFINITIES (TYPE_MODE (type))
1671 && REAL_VALUE_ISINF (value)
1672 && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1)))
1673 TREE_OVERFLOW (t) = 1;
1675 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1679 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1680 to a floating point type. */
1683 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
1685 REAL_VALUE_TYPE value;
1688 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
1689 t = build_real (type, value);
1691 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1695 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1696 to another fixed-point type. */
1699 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
1701 FIXED_VALUE_TYPE value;
1705 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
1706 TYPE_SATURATING (type));
1707 t = build_fixed (type, value);
1709 /* Propagate overflow flags. */
1710 if (overflow_p | TREE_OVERFLOW (arg1))
1711 TREE_OVERFLOW (t) = 1;
1715 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
1716 to a fixed-point type. */
1719 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
1721 FIXED_VALUE_TYPE value;
1725 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
1726 TREE_INT_CST (arg1),
1727 TYPE_UNSIGNED (TREE_TYPE (arg1)),
1728 TYPE_SATURATING (type));
1729 t = build_fixed (type, value);
1731 /* Propagate overflow flags. */
1732 if (overflow_p | TREE_OVERFLOW (arg1))
1733 TREE_OVERFLOW (t) = 1;
1737 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1738 to a fixed-point type. */
1741 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
1743 FIXED_VALUE_TYPE value;
1747 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
1748 &TREE_REAL_CST (arg1),
1749 TYPE_SATURATING (type));
1750 t = build_fixed (type, value);
1752 /* Propagate overflow flags. */
1753 if (overflow_p | TREE_OVERFLOW (arg1))
1754 TREE_OVERFLOW (t) = 1;
1758 /* Attempt to fold type conversion operation CODE of expression ARG1 to
1759 type TYPE. If no simplification can be done return NULL_TREE. */
1762 fold_convert_const (enum tree_code code, tree type, tree arg1)
1764 if (TREE_TYPE (arg1) == type)
1767 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
1768 || TREE_CODE (type) == OFFSET_TYPE)
1770 if (TREE_CODE (arg1) == INTEGER_CST)
1771 return fold_convert_const_int_from_int (type, arg1);
1772 else if (TREE_CODE (arg1) == REAL_CST)
1773 return fold_convert_const_int_from_real (code, type, arg1);
1774 else if (TREE_CODE (arg1) == FIXED_CST)
1775 return fold_convert_const_int_from_fixed (type, arg1);
1777 else if (TREE_CODE (type) == REAL_TYPE)
1779 if (TREE_CODE (arg1) == INTEGER_CST)
1780 return build_real_from_int_cst (type, arg1);
1781 else if (TREE_CODE (arg1) == REAL_CST)
1782 return fold_convert_const_real_from_real (type, arg1);
1783 else if (TREE_CODE (arg1) == FIXED_CST)
1784 return fold_convert_const_real_from_fixed (type, arg1);
1786 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
1788 if (TREE_CODE (arg1) == FIXED_CST)
1789 return fold_convert_const_fixed_from_fixed (type, arg1);
1790 else if (TREE_CODE (arg1) == INTEGER_CST)
1791 return fold_convert_const_fixed_from_int (type, arg1);
1792 else if (TREE_CODE (arg1) == REAL_CST)
1793 return fold_convert_const_fixed_from_real (type, arg1);
1798 /* Construct a vector of zero elements of vector type TYPE. */
1801 build_zero_vector (tree type)
1805 t = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1806 return build_vector_from_val (type, t);
1809 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
1812 fold_convertible_p (const_tree type, const_tree arg)
1814 tree orig = TREE_TYPE (arg);
1819 if (TREE_CODE (arg) == ERROR_MARK
1820 || TREE_CODE (type) == ERROR_MARK
1821 || TREE_CODE (orig) == ERROR_MARK)
1824 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
1827 switch (TREE_CODE (type))
1829 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1830 case POINTER_TYPE: case REFERENCE_TYPE:
1832 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1833 || TREE_CODE (orig) == OFFSET_TYPE)
1835 return (TREE_CODE (orig) == VECTOR_TYPE
1836 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1839 case FIXED_POINT_TYPE:
1843 return TREE_CODE (type) == TREE_CODE (orig);
1850 /* Convert expression ARG to type TYPE. Used by the middle-end for
1851 simple conversions in preference to calling the front-end's convert. */
1854 fold_convert_loc (location_t loc, tree type, tree arg)
1856 tree orig = TREE_TYPE (arg);
1862 if (TREE_CODE (arg) == ERROR_MARK
1863 || TREE_CODE (type) == ERROR_MARK
1864 || TREE_CODE (orig) == ERROR_MARK)
1865 return error_mark_node;
1867 switch (TREE_CODE (type))
1870 case REFERENCE_TYPE:
1871 /* Handle conversions between pointers to different address spaces. */
1872 if (POINTER_TYPE_P (orig)
1873 && (TYPE_ADDR_SPACE (TREE_TYPE (type))
1874 != TYPE_ADDR_SPACE (TREE_TYPE (orig))))
1875 return fold_build1_loc (loc, ADDR_SPACE_CONVERT_EXPR, type, arg);
1878 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1880 if (TREE_CODE (arg) == INTEGER_CST)
1882 tem = fold_convert_const (NOP_EXPR, type, arg);
1883 if (tem != NULL_TREE)
1886 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1887 || TREE_CODE (orig) == OFFSET_TYPE)
1888 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1889 if (TREE_CODE (orig) == COMPLEX_TYPE)
1890 return fold_convert_loc (loc, type,
1891 fold_build1_loc (loc, REALPART_EXPR,
1892 TREE_TYPE (orig), arg));
1893 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
1894 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1895 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1898 if (TREE_CODE (arg) == INTEGER_CST)
1900 tem = fold_convert_const (FLOAT_EXPR, type, arg);
1901 if (tem != NULL_TREE)
1904 else if (TREE_CODE (arg) == REAL_CST)
1906 tem = fold_convert_const (NOP_EXPR, type, arg);
1907 if (tem != NULL_TREE)
1910 else if (TREE_CODE (arg) == FIXED_CST)
1912 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1913 if (tem != NULL_TREE)
1917 switch (TREE_CODE (orig))
1920 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1921 case POINTER_TYPE: case REFERENCE_TYPE:
1922 return fold_build1_loc (loc, FLOAT_EXPR, type, arg);
1925 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1927 case FIXED_POINT_TYPE:
1928 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1931 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1932 return fold_convert_loc (loc, type, tem);
1938 case FIXED_POINT_TYPE:
1939 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
1940 || TREE_CODE (arg) == REAL_CST)
1942 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1943 if (tem != NULL_TREE)
1944 goto fold_convert_exit;
1947 switch (TREE_CODE (orig))
1949 case FIXED_POINT_TYPE:
1954 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1957 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1958 return fold_convert_loc (loc, type, tem);
1965 switch (TREE_CODE (orig))
1968 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1969 case POINTER_TYPE: case REFERENCE_TYPE:
1971 case FIXED_POINT_TYPE:
1972 return fold_build2_loc (loc, COMPLEX_EXPR, type,
1973 fold_convert_loc (loc, TREE_TYPE (type), arg),
1974 fold_convert_loc (loc, TREE_TYPE (type),
1975 integer_zero_node));
1980 if (TREE_CODE (arg) == COMPLEX_EXPR)
1982 rpart = fold_convert_loc (loc, TREE_TYPE (type),
1983 TREE_OPERAND (arg, 0));
1984 ipart = fold_convert_loc (loc, TREE_TYPE (type),
1985 TREE_OPERAND (arg, 1));
1986 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
1989 arg = save_expr (arg);
1990 rpart = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1991 ipart = fold_build1_loc (loc, IMAGPART_EXPR, TREE_TYPE (orig), arg);
1992 rpart = fold_convert_loc (loc, TREE_TYPE (type), rpart);
1993 ipart = fold_convert_loc (loc, TREE_TYPE (type), ipart);
1994 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2002 if (integer_zerop (arg))
2003 return build_zero_vector (type);
2004 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2005 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2006 || TREE_CODE (orig) == VECTOR_TYPE);
2007 return fold_build1_loc (loc, VIEW_CONVERT_EXPR, type, arg);
2010 tem = fold_ignored_result (arg);
2011 return fold_build1_loc (loc, NOP_EXPR, type, tem);
2014 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2015 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2019 protected_set_expr_location_unshare (tem, loc);
2023 /* Return false if expr can be assumed not to be an lvalue, true
2027 maybe_lvalue_p (const_tree x)
2029 /* We only need to wrap lvalue tree codes. */
2030 switch (TREE_CODE (x))
2043 case ARRAY_RANGE_REF:
2049 case PREINCREMENT_EXPR:
2050 case PREDECREMENT_EXPR:
2052 case TRY_CATCH_EXPR:
2053 case WITH_CLEANUP_EXPR:
2062 /* Assume the worst for front-end tree codes. */
2063 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2071 /* Return an expr equal to X but certainly not valid as an lvalue. */
2074 non_lvalue_loc (location_t loc, tree x)
2076 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2081 if (! maybe_lvalue_p (x))
2083 return build1_loc (loc, NON_LVALUE_EXPR, TREE_TYPE (x), x);
2086 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2087 Zero means allow extended lvalues. */
2089 int pedantic_lvalues;
2091 /* When pedantic, return an expr equal to X but certainly not valid as a
2092 pedantic lvalue. Otherwise, return X. */
2095 pedantic_non_lvalue_loc (location_t loc, tree x)
2097 if (pedantic_lvalues)
2098 return non_lvalue_loc (loc, x);
2100 return protected_set_expr_location_unshare (x, loc);
2103 /* Given a tree comparison code, return the code that is the logical inverse.
2104 It is generally not safe to do this for floating-point comparisons, except
2105 for EQ_EXPR and NE_EXPR, so we return ERROR_MARK in this case. */
2108 invert_tree_comparison (enum tree_code code, bool honor_nans)
2110 if (honor_nans && flag_trapping_math && code != EQ_EXPR && code != NE_EXPR)
2120 return honor_nans ? UNLE_EXPR : LE_EXPR;
2122 return honor_nans ? UNLT_EXPR : LT_EXPR;
2124 return honor_nans ? UNGE_EXPR : GE_EXPR;
2126 return honor_nans ? UNGT_EXPR : GT_EXPR;
2140 return UNORDERED_EXPR;
2141 case UNORDERED_EXPR:
2142 return ORDERED_EXPR;
2148 /* Similar, but return the comparison that results if the operands are
2149 swapped. This is safe for floating-point. */
2152 swap_tree_comparison (enum tree_code code)
2159 case UNORDERED_EXPR:
2185 /* Convert a comparison tree code from an enum tree_code representation
2186 into a compcode bit-based encoding. This function is the inverse of
2187 compcode_to_comparison. */
2189 static enum comparison_code
2190 comparison_to_compcode (enum tree_code code)
2207 return COMPCODE_ORD;
2208 case UNORDERED_EXPR:
2209 return COMPCODE_UNORD;
2211 return COMPCODE_UNLT;
2213 return COMPCODE_UNEQ;
2215 return COMPCODE_UNLE;
2217 return COMPCODE_UNGT;
2219 return COMPCODE_LTGT;
2221 return COMPCODE_UNGE;
2227 /* Convert a compcode bit-based encoding of a comparison operator back
2228 to GCC's enum tree_code representation. This function is the
2229 inverse of comparison_to_compcode. */
2231 static enum tree_code
2232 compcode_to_comparison (enum comparison_code code)
2249 return ORDERED_EXPR;
2250 case COMPCODE_UNORD:
2251 return UNORDERED_EXPR;
2269 /* Return a tree for the comparison which is the combination of
2270 doing the AND or OR (depending on CODE) of the two operations LCODE
2271 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2272 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2273 if this makes the transformation invalid. */
2276 combine_comparisons (location_t loc,
2277 enum tree_code code, enum tree_code lcode,
2278 enum tree_code rcode, tree truth_type,
2279 tree ll_arg, tree lr_arg)
2281 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2282 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2283 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2288 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2289 compcode = lcompcode & rcompcode;
2292 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2293 compcode = lcompcode | rcompcode;
2302 /* Eliminate unordered comparisons, as well as LTGT and ORD
2303 which are not used unless the mode has NaNs. */
2304 compcode &= ~COMPCODE_UNORD;
2305 if (compcode == COMPCODE_LTGT)
2306 compcode = COMPCODE_NE;
2307 else if (compcode == COMPCODE_ORD)
2308 compcode = COMPCODE_TRUE;
2310 else if (flag_trapping_math)
2312 /* Check that the original operation and the optimized ones will trap
2313 under the same condition. */
2314 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2315 && (lcompcode != COMPCODE_EQ)
2316 && (lcompcode != COMPCODE_ORD);
2317 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2318 && (rcompcode != COMPCODE_EQ)
2319 && (rcompcode != COMPCODE_ORD);
2320 bool trap = (compcode & COMPCODE_UNORD) == 0
2321 && (compcode != COMPCODE_EQ)
2322 && (compcode != COMPCODE_ORD);
2324 /* In a short-circuited boolean expression the LHS might be
2325 such that the RHS, if evaluated, will never trap. For
2326 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2327 if neither x nor y is NaN. (This is a mixed blessing: for
2328 example, the expression above will never trap, hence
2329 optimizing it to x < y would be invalid). */
2330 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2331 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2334 /* If the comparison was short-circuited, and only the RHS
2335 trapped, we may now generate a spurious trap. */
2337 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2340 /* If we changed the conditions that cause a trap, we lose. */
2341 if ((ltrap || rtrap) != trap)
2345 if (compcode == COMPCODE_TRUE)
2346 return constant_boolean_node (true, truth_type);
2347 else if (compcode == COMPCODE_FALSE)
2348 return constant_boolean_node (false, truth_type);
2351 enum tree_code tcode;
2353 tcode = compcode_to_comparison ((enum comparison_code) compcode);
2354 return fold_build2_loc (loc, tcode, truth_type, ll_arg, lr_arg);
2358 /* Return nonzero if two operands (typically of the same tree node)
2359 are necessarily equal. If either argument has side-effects this
2360 function returns zero. FLAGS modifies behavior as follows:
2362 If OEP_ONLY_CONST is set, only return nonzero for constants.
2363 This function tests whether the operands are indistinguishable;
2364 it does not test whether they are equal using C's == operation.
2365 The distinction is important for IEEE floating point, because
2366 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2367 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2369 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2370 even though it may hold multiple values during a function.
2371 This is because a GCC tree node guarantees that nothing else is
2372 executed between the evaluation of its "operands" (which may often
2373 be evaluated in arbitrary order). Hence if the operands themselves
2374 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
2375 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
2376 unset means assuming isochronic (or instantaneous) tree equivalence.
2377 Unless comparing arbitrary expression trees, such as from different
2378 statements, this flag can usually be left unset.
2380 If OEP_PURE_SAME is set, then pure functions with identical arguments
2381 are considered the same. It is used when the caller has other ways
2382 to ensure that global memory is unchanged in between. */
2385 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
2387 /* If either is ERROR_MARK, they aren't equal. */
2388 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK
2389 || TREE_TYPE (arg0) == error_mark_node
2390 || TREE_TYPE (arg1) == error_mark_node)
2393 /* Similar, if either does not have a type (like a released SSA name),
2394 they aren't equal. */
2395 if (!TREE_TYPE (arg0) || !TREE_TYPE (arg1))
2398 /* Check equality of integer constants before bailing out due to
2399 precision differences. */
2400 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2401 return tree_int_cst_equal (arg0, arg1);
2403 /* If both types don't have the same signedness, then we can't consider
2404 them equal. We must check this before the STRIP_NOPS calls
2405 because they may change the signedness of the arguments. As pointers
2406 strictly don't have a signedness, require either two pointers or
2407 two non-pointers as well. */
2408 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
2409 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
2412 /* We cannot consider pointers to different address space equal. */
2413 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && POINTER_TYPE_P (TREE_TYPE (arg1))
2414 && (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg0)))
2415 != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg1)))))
2418 /* If both types don't have the same precision, then it is not safe
2420 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
2426 /* In case both args are comparisons but with different comparison
2427 code, try to swap the comparison operands of one arg to produce
2428 a match and compare that variant. */
2429 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2430 && COMPARISON_CLASS_P (arg0)
2431 && COMPARISON_CLASS_P (arg1))
2433 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
2435 if (TREE_CODE (arg0) == swap_code)
2436 return operand_equal_p (TREE_OPERAND (arg0, 0),
2437 TREE_OPERAND (arg1, 1), flags)
2438 && operand_equal_p (TREE_OPERAND (arg0, 1),
2439 TREE_OPERAND (arg1, 0), flags);
2442 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2443 /* This is needed for conversions and for COMPONENT_REF.
2444 Might as well play it safe and always test this. */
2445 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
2446 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
2447 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
2450 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
2451 We don't care about side effects in that case because the SAVE_EXPR
2452 takes care of that for us. In all other cases, two expressions are
2453 equal if they have no side effects. If we have two identical
2454 expressions with side effects that should be treated the same due
2455 to the only side effects being identical SAVE_EXPR's, that will
2456 be detected in the recursive calls below.
2457 If we are taking an invariant address of two identical objects
2458 they are necessarily equal as well. */
2459 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
2460 && (TREE_CODE (arg0) == SAVE_EXPR
2461 || (flags & OEP_CONSTANT_ADDRESS_OF)
2462 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
2465 /* Next handle constant cases, those for which we can return 1 even
2466 if ONLY_CONST is set. */
2467 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
2468 switch (TREE_CODE (arg0))
2471 return tree_int_cst_equal (arg0, arg1);
2474 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
2475 TREE_FIXED_CST (arg1));
2478 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
2479 TREE_REAL_CST (arg1)))
2483 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
2485 /* If we do not distinguish between signed and unsigned zero,
2486 consider them equal. */
2487 if (real_zerop (arg0) && real_zerop (arg1))
2496 v1 = TREE_VECTOR_CST_ELTS (arg0);
2497 v2 = TREE_VECTOR_CST_ELTS (arg1);
2500 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
2503 v1 = TREE_CHAIN (v1);
2504 v2 = TREE_CHAIN (v2);
2511 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
2513 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
2517 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
2518 && ! memcmp (TREE_STRING_POINTER (arg0),
2519 TREE_STRING_POINTER (arg1),
2520 TREE_STRING_LENGTH (arg0)));
2523 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
2524 TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)
2525 ? OEP_CONSTANT_ADDRESS_OF : 0);
2530 if (flags & OEP_ONLY_CONST)
2533 /* Define macros to test an operand from arg0 and arg1 for equality and a
2534 variant that allows null and views null as being different from any
2535 non-null value. In the latter case, if either is null, the both
2536 must be; otherwise, do the normal comparison. */
2537 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
2538 TREE_OPERAND (arg1, N), flags)
2540 #define OP_SAME_WITH_NULL(N) \
2541 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
2542 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
2544 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
2547 /* Two conversions are equal only if signedness and modes match. */
2548 switch (TREE_CODE (arg0))
2551 case FIX_TRUNC_EXPR:
2552 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
2553 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
2563 case tcc_comparison:
2565 if (OP_SAME (0) && OP_SAME (1))
2568 /* For commutative ops, allow the other order. */
2569 return (commutative_tree_code (TREE_CODE (arg0))
2570 && operand_equal_p (TREE_OPERAND (arg0, 0),
2571 TREE_OPERAND (arg1, 1), flags)
2572 && operand_equal_p (TREE_OPERAND (arg0, 1),
2573 TREE_OPERAND (arg1, 0), flags));
2576 /* If either of the pointer (or reference) expressions we are
2577 dereferencing contain a side effect, these cannot be equal. */
2578 if (TREE_SIDE_EFFECTS (arg0)
2579 || TREE_SIDE_EFFECTS (arg1))
2582 switch (TREE_CODE (arg0))
2590 /* Require equal access sizes, and similar pointer types.
2591 We can have incomplete types for array references of
2592 variable-sized arrays from the Fortran frontent
2594 return ((TYPE_SIZE (TREE_TYPE (arg0)) == TYPE_SIZE (TREE_TYPE (arg1))
2595 || (TYPE_SIZE (TREE_TYPE (arg0))
2596 && TYPE_SIZE (TREE_TYPE (arg1))
2597 && operand_equal_p (TYPE_SIZE (TREE_TYPE (arg0)),
2598 TYPE_SIZE (TREE_TYPE (arg1)), flags)))
2599 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg0, 1)))
2600 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg1, 1))))
2601 && OP_SAME (0) && OP_SAME (1));
2604 case ARRAY_RANGE_REF:
2605 /* Operands 2 and 3 may be null.
2606 Compare the array index by value if it is constant first as we
2607 may have different types but same value here. */
2609 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
2610 TREE_OPERAND (arg1, 1))
2612 && OP_SAME_WITH_NULL (2)
2613 && OP_SAME_WITH_NULL (3));
2616 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
2617 may be NULL when we're called to compare MEM_EXPRs. */
2618 return OP_SAME_WITH_NULL (0)
2620 && OP_SAME_WITH_NULL (2);
2623 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2629 case tcc_expression:
2630 switch (TREE_CODE (arg0))
2633 case TRUTH_NOT_EXPR:
2636 case TRUTH_ANDIF_EXPR:
2637 case TRUTH_ORIF_EXPR:
2638 return OP_SAME (0) && OP_SAME (1);
2641 case WIDEN_MULT_PLUS_EXPR:
2642 case WIDEN_MULT_MINUS_EXPR:
2645 /* The multiplcation operands are commutative. */
2648 case TRUTH_AND_EXPR:
2650 case TRUTH_XOR_EXPR:
2651 if (OP_SAME (0) && OP_SAME (1))
2654 /* Otherwise take into account this is a commutative operation. */
2655 return (operand_equal_p (TREE_OPERAND (arg0, 0),
2656 TREE_OPERAND (arg1, 1), flags)
2657 && operand_equal_p (TREE_OPERAND (arg0, 1),
2658 TREE_OPERAND (arg1, 0), flags));
2663 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2670 switch (TREE_CODE (arg0))
2673 /* If the CALL_EXPRs call different functions, then they
2674 clearly can not be equal. */
2675 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
2680 unsigned int cef = call_expr_flags (arg0);
2681 if (flags & OEP_PURE_SAME)
2682 cef &= ECF_CONST | ECF_PURE;
2689 /* Now see if all the arguments are the same. */
2691 const_call_expr_arg_iterator iter0, iter1;
2693 for (a0 = first_const_call_expr_arg (arg0, &iter0),
2694 a1 = first_const_call_expr_arg (arg1, &iter1);
2696 a0 = next_const_call_expr_arg (&iter0),
2697 a1 = next_const_call_expr_arg (&iter1))
2698 if (! operand_equal_p (a0, a1, flags))
2701 /* If we get here and both argument lists are exhausted
2702 then the CALL_EXPRs are equal. */
2703 return ! (a0 || a1);
2709 case tcc_declaration:
2710 /* Consider __builtin_sqrt equal to sqrt. */
2711 return (TREE_CODE (arg0) == FUNCTION_DECL
2712 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
2713 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
2714 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
2721 #undef OP_SAME_WITH_NULL
2724 /* Similar to operand_equal_p, but see if ARG0 might have been made by
2725 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
2727 When in doubt, return 0. */
2730 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
2732 int unsignedp1, unsignedpo;
2733 tree primarg0, primarg1, primother;
2734 unsigned int correct_width;
2736 if (operand_equal_p (arg0, arg1, 0))
2739 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
2740 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
2743 /* Discard any conversions that don't change the modes of ARG0 and ARG1
2744 and see if the inner values are the same. This removes any
2745 signedness comparison, which doesn't matter here. */
2746 primarg0 = arg0, primarg1 = arg1;
2747 STRIP_NOPS (primarg0);
2748 STRIP_NOPS (primarg1);
2749 if (operand_equal_p (primarg0, primarg1, 0))
2752 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
2753 actual comparison operand, ARG0.
2755 First throw away any conversions to wider types
2756 already present in the operands. */
2758 primarg1 = get_narrower (arg1, &unsignedp1);
2759 primother = get_narrower (other, &unsignedpo);
2761 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
2762 if (unsignedp1 == unsignedpo
2763 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
2764 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
2766 tree type = TREE_TYPE (arg0);
2768 /* Make sure shorter operand is extended the right way
2769 to match the longer operand. */
2770 primarg1 = fold_convert (signed_or_unsigned_type_for
2771 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
2773 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
2780 /* See if ARG is an expression that is either a comparison or is performing
2781 arithmetic on comparisons. The comparisons must only be comparing
2782 two different values, which will be stored in *CVAL1 and *CVAL2; if
2783 they are nonzero it means that some operands have already been found.
2784 No variables may be used anywhere else in the expression except in the
2785 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
2786 the expression and save_expr needs to be called with CVAL1 and CVAL2.
2788 If this is true, return 1. Otherwise, return zero. */
2791 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
2793 enum tree_code code = TREE_CODE (arg);
2794 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2796 /* We can handle some of the tcc_expression cases here. */
2797 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2799 else if (tclass == tcc_expression
2800 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
2801 || code == COMPOUND_EXPR))
2802 tclass = tcc_binary;
2804 else if (tclass == tcc_expression && code == SAVE_EXPR
2805 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
2807 /* If we've already found a CVAL1 or CVAL2, this expression is
2808 two complex to handle. */
2809 if (*cval1 || *cval2)
2819 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
2822 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
2823 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2824 cval1, cval2, save_p));
2829 case tcc_expression:
2830 if (code == COND_EXPR)
2831 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
2832 cval1, cval2, save_p)
2833 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2834 cval1, cval2, save_p)
2835 && twoval_comparison_p (TREE_OPERAND (arg, 2),
2836 cval1, cval2, save_p));
2839 case tcc_comparison:
2840 /* First see if we can handle the first operand, then the second. For
2841 the second operand, we know *CVAL1 can't be zero. It must be that
2842 one side of the comparison is each of the values; test for the
2843 case where this isn't true by failing if the two operands
2846 if (operand_equal_p (TREE_OPERAND (arg, 0),
2847 TREE_OPERAND (arg, 1), 0))
2851 *cval1 = TREE_OPERAND (arg, 0);
2852 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
2854 else if (*cval2 == 0)
2855 *cval2 = TREE_OPERAND (arg, 0);
2856 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
2861 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
2863 else if (*cval2 == 0)
2864 *cval2 = TREE_OPERAND (arg, 1);
2865 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
2877 /* ARG is a tree that is known to contain just arithmetic operations and
2878 comparisons. Evaluate the operations in the tree substituting NEW0 for
2879 any occurrence of OLD0 as an operand of a comparison and likewise for
2883 eval_subst (location_t loc, tree arg, tree old0, tree new0,
2884 tree old1, tree new1)
2886 tree type = TREE_TYPE (arg);
2887 enum tree_code code = TREE_CODE (arg);
2888 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2890 /* We can handle some of the tcc_expression cases here. */
2891 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2893 else if (tclass == tcc_expression
2894 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2895 tclass = tcc_binary;
2900 return fold_build1_loc (loc, code, type,
2901 eval_subst (loc, TREE_OPERAND (arg, 0),
2902 old0, new0, old1, new1));
2905 return fold_build2_loc (loc, code, type,
2906 eval_subst (loc, TREE_OPERAND (arg, 0),
2907 old0, new0, old1, new1),
2908 eval_subst (loc, TREE_OPERAND (arg, 1),
2909 old0, new0, old1, new1));
2911 case tcc_expression:
2915 return eval_subst (loc, TREE_OPERAND (arg, 0), old0, new0,
2919 return eval_subst (loc, TREE_OPERAND (arg, 1), old0, new0,
2923 return fold_build3_loc (loc, code, type,
2924 eval_subst (loc, TREE_OPERAND (arg, 0),
2925 old0, new0, old1, new1),
2926 eval_subst (loc, TREE_OPERAND (arg, 1),
2927 old0, new0, old1, new1),
2928 eval_subst (loc, TREE_OPERAND (arg, 2),
2929 old0, new0, old1, new1));
2933 /* Fall through - ??? */
2935 case tcc_comparison:
2937 tree arg0 = TREE_OPERAND (arg, 0);
2938 tree arg1 = TREE_OPERAND (arg, 1);
2940 /* We need to check both for exact equality and tree equality. The
2941 former will be true if the operand has a side-effect. In that
2942 case, we know the operand occurred exactly once. */
2944 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
2946 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
2949 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
2951 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
2954 return fold_build2_loc (loc, code, type, arg0, arg1);
2962 /* Return a tree for the case when the result of an expression is RESULT
2963 converted to TYPE and OMITTED was previously an operand of the expression
2964 but is now not needed (e.g., we folded OMITTED * 0).
2966 If OMITTED has side effects, we must evaluate it. Otherwise, just do
2967 the conversion of RESULT to TYPE. */
2970 omit_one_operand_loc (location_t loc, tree type, tree result, tree omitted)
2972 tree t = fold_convert_loc (loc, type, result);
2974 /* If the resulting operand is an empty statement, just return the omitted
2975 statement casted to void. */
2976 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
2977 return build1_loc (loc, NOP_EXPR, void_type_node,
2978 fold_ignored_result (omitted));
2980 if (TREE_SIDE_EFFECTS (omitted))
2981 return build2_loc (loc, COMPOUND_EXPR, type,
2982 fold_ignored_result (omitted), t);
2984 return non_lvalue_loc (loc, t);
2987 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
2990 pedantic_omit_one_operand_loc (location_t loc, tree type, tree result,
2993 tree t = fold_convert_loc (loc, type, result);
2995 /* If the resulting operand is an empty statement, just return the omitted
2996 statement casted to void. */
2997 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
2998 return build1_loc (loc, NOP_EXPR, void_type_node,
2999 fold_ignored_result (omitted));
3001 if (TREE_SIDE_EFFECTS (omitted))
3002 return build2_loc (loc, COMPOUND_EXPR, type,
3003 fold_ignored_result (omitted), t);
3005 return pedantic_non_lvalue_loc (loc, t);
3008 /* Return a tree for the case when the result of an expression is RESULT
3009 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3010 of the expression but are now not needed.
3012 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3013 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3014 evaluated before OMITTED2. Otherwise, if neither has side effects,
3015 just do the conversion of RESULT to TYPE. */
3018 omit_two_operands_loc (location_t loc, tree type, tree result,
3019 tree omitted1, tree omitted2)
3021 tree t = fold_convert_loc (loc, type, result);
3023 if (TREE_SIDE_EFFECTS (omitted2))
3024 t = build2_loc (loc, COMPOUND_EXPR, type, omitted2, t);
3025 if (TREE_SIDE_EFFECTS (omitted1))
3026 t = build2_loc (loc, COMPOUND_EXPR, type, omitted1, t);
3028 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue_loc (loc, t) : t;
3032 /* Return a simplified tree node for the truth-negation of ARG. This
3033 never alters ARG itself. We assume that ARG is an operation that
3034 returns a truth value (0 or 1).
3036 FIXME: one would think we would fold the result, but it causes
3037 problems with the dominator optimizer. */
3040 fold_truth_not_expr (location_t loc, tree arg)
3042 tree type = TREE_TYPE (arg);
3043 enum tree_code code = TREE_CODE (arg);
3044 location_t loc1, loc2;
3046 /* If this is a comparison, we can simply invert it, except for
3047 floating-point non-equality comparisons, in which case we just
3048 enclose a TRUTH_NOT_EXPR around what we have. */
3050 if (TREE_CODE_CLASS (code) == tcc_comparison)
3052 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3053 if (FLOAT_TYPE_P (op_type)
3054 && flag_trapping_math
3055 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3056 && code != NE_EXPR && code != EQ_EXPR)
3059 code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (op_type)));
3060 if (code == ERROR_MARK)
3063 return build2_loc (loc, code, type, TREE_OPERAND (arg, 0),
3064 TREE_OPERAND (arg, 1));
3070 return constant_boolean_node (integer_zerop (arg), type);
3072 case TRUTH_AND_EXPR:
3073 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3074 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3075 return build2_loc (loc, TRUTH_OR_EXPR, type,
3076 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3077 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3080 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3081 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3082 return build2_loc (loc, TRUTH_AND_EXPR, type,
3083 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3084 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3086 case TRUTH_XOR_EXPR:
3087 /* Here we can invert either operand. We invert the first operand
3088 unless the second operand is a TRUTH_NOT_EXPR in which case our
3089 result is the XOR of the first operand with the inside of the
3090 negation of the second operand. */
3092 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3093 return build2_loc (loc, TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3094 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3096 return build2_loc (loc, TRUTH_XOR_EXPR, type,
3097 invert_truthvalue_loc (loc, TREE_OPERAND (arg, 0)),
3098 TREE_OPERAND (arg, 1));
3100 case TRUTH_ANDIF_EXPR:
3101 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3102 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3103 return build2_loc (loc, TRUTH_ORIF_EXPR, type,
3104 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3105 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3107 case TRUTH_ORIF_EXPR:
3108 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3109 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3110 return build2_loc (loc, TRUTH_ANDIF_EXPR, type,
3111 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3112 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3114 case TRUTH_NOT_EXPR:
3115 return TREE_OPERAND (arg, 0);
3119 tree arg1 = TREE_OPERAND (arg, 1);
3120 tree arg2 = TREE_OPERAND (arg, 2);
3122 loc1 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3123 loc2 = expr_location_or (TREE_OPERAND (arg, 2), loc);
3125 /* A COND_EXPR may have a throw as one operand, which
3126 then has void type. Just leave void operands
3128 return build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg, 0),
3129 VOID_TYPE_P (TREE_TYPE (arg1))
3130 ? arg1 : invert_truthvalue_loc (loc1, arg1),
3131 VOID_TYPE_P (TREE_TYPE (arg2))
3132 ? arg2 : invert_truthvalue_loc (loc2, arg2));
3136 loc1 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3137 return build2_loc (loc, COMPOUND_EXPR, type,
3138 TREE_OPERAND (arg, 0),
3139 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 1)));
3141 case NON_LVALUE_EXPR:
3142 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3143 return invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0));
3146 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3147 return build1_loc (loc, TRUTH_NOT_EXPR, type, arg);
3149 /* ... fall through ... */
3152 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3153 return build1_loc (loc, TREE_CODE (arg), type,
3154 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3157 if (!integer_onep (TREE_OPERAND (arg, 1)))
3159 return build2_loc (loc, EQ_EXPR, type, arg, build_int_cst (type, 0));
3162 return build1_loc (loc, TRUTH_NOT_EXPR, type, arg);
3164 case CLEANUP_POINT_EXPR:
3165 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3166 return build1_loc (loc, CLEANUP_POINT_EXPR, type,
3167 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3174 /* Return a simplified tree node for the truth-negation of ARG. This
3175 never alters ARG itself. We assume that ARG is an operation that
3176 returns a truth value (0 or 1).
3178 FIXME: one would think we would fold the result, but it causes
3179 problems with the dominator optimizer. */
3182 invert_truthvalue_loc (location_t loc, tree arg)
3186 if (TREE_CODE (arg) == ERROR_MARK)
3189 tem = fold_truth_not_expr (loc, arg);
3191 tem = build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3196 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3197 operands are another bit-wise operation with a common input. If so,
3198 distribute the bit operations to save an operation and possibly two if
3199 constants are involved. For example, convert
3200 (A | B) & (A | C) into A | (B & C)
3201 Further simplification will occur if B and C are constants.
3203 If this optimization cannot be done, 0 will be returned. */
3206 distribute_bit_expr (location_t loc, enum tree_code code, tree type,
3207 tree arg0, tree arg1)
3212 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3213 || TREE_CODE (arg0) == code
3214 || (TREE_CODE (arg0) != BIT_AND_EXPR
3215 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3218 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3220 common = TREE_OPERAND (arg0, 0);
3221 left = TREE_OPERAND (arg0, 1);
3222 right = TREE_OPERAND (arg1, 1);
3224 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3226 common = TREE_OPERAND (arg0, 0);
3227 left = TREE_OPERAND (arg0, 1);
3228 right = TREE_OPERAND (arg1, 0);
3230 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3232 common = TREE_OPERAND (arg0, 1);
3233 left = TREE_OPERAND (arg0, 0);
3234 right = TREE_OPERAND (arg1, 1);
3236 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3238 common = TREE_OPERAND (arg0, 1);
3239 left = TREE_OPERAND (arg0, 0);
3240 right = TREE_OPERAND (arg1, 0);
3245 common = fold_convert_loc (loc, type, common);
3246 left = fold_convert_loc (loc, type, left);
3247 right = fold_convert_loc (loc, type, right);
3248 return fold_build2_loc (loc, TREE_CODE (arg0), type, common,
3249 fold_build2_loc (loc, code, type, left, right));
3252 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3253 with code CODE. This optimization is unsafe. */
3255 distribute_real_division (location_t loc, enum tree_code code, tree type,
3256 tree arg0, tree arg1)
3258 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3259 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3261 /* (A / C) +- (B / C) -> (A +- B) / C. */
3263 && operand_equal_p (TREE_OPERAND (arg0, 1),
3264 TREE_OPERAND (arg1, 1), 0))
3265 return fold_build2_loc (loc, mul0 ? MULT_EXPR : RDIV_EXPR, type,
3266 fold_build2_loc (loc, code, type,
3267 TREE_OPERAND (arg0, 0),
3268 TREE_OPERAND (arg1, 0)),
3269 TREE_OPERAND (arg0, 1));
3271 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3272 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3273 TREE_OPERAND (arg1, 0), 0)
3274 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3275 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3277 REAL_VALUE_TYPE r0, r1;
3278 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3279 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3281 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3283 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3284 real_arithmetic (&r0, code, &r0, &r1);
3285 return fold_build2_loc (loc, MULT_EXPR, type,
3286 TREE_OPERAND (arg0, 0),
3287 build_real (type, r0));
3293 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3294 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3297 make_bit_field_ref (location_t loc, tree inner, tree type,
3298 HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos, int unsignedp)
3300 tree result, bftype;
3304 tree size = TYPE_SIZE (TREE_TYPE (inner));
3305 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
3306 || POINTER_TYPE_P (TREE_TYPE (inner)))
3307 && host_integerp (size, 0)
3308 && tree_low_cst (size, 0) == bitsize)
3309 return fold_convert_loc (loc, type, inner);
3313 if (TYPE_PRECISION (bftype) != bitsize
3314 || TYPE_UNSIGNED (bftype) == !unsignedp)
3315 bftype = build_nonstandard_integer_type (bitsize, 0);
3317 result = build3_loc (loc, BIT_FIELD_REF, bftype, inner,
3318 size_int (bitsize), bitsize_int (bitpos));
3321 result = fold_convert_loc (loc, type, result);
3326 /* Optimize a bit-field compare.
3328 There are two cases: First is a compare against a constant and the
3329 second is a comparison of two items where the fields are at the same
3330 bit position relative to the start of a chunk (byte, halfword, word)
3331 large enough to contain it. In these cases we can avoid the shift
3332 implicit in bitfield extractions.
3334 For constants, we emit a compare of the shifted constant with the
3335 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3336 compared. For two fields at the same position, we do the ANDs with the
3337 similar mask and compare the result of the ANDs.
3339 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3340 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3341 are the left and right operands of the comparison, respectively.
3343 If the optimization described above can be done, we return the resulting
3344 tree. Otherwise we return zero. */
3347 optimize_bit_field_compare (location_t loc, enum tree_code code,
3348 tree compare_type, tree lhs, tree rhs)
3350 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
3351 tree type = TREE_TYPE (lhs);
3352 tree signed_type, unsigned_type;
3353 int const_p = TREE_CODE (rhs) == INTEGER_CST;
3354 enum machine_mode lmode, rmode, nmode;
3355 int lunsignedp, runsignedp;
3356 int lvolatilep = 0, rvolatilep = 0;
3357 tree linner, rinner = NULL_TREE;
3361 /* Get all the information about the extractions being done. If the bit size
3362 if the same as the size of the underlying object, we aren't doing an
3363 extraction at all and so can do nothing. We also don't want to
3364 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3365 then will no longer be able to replace it. */
3366 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
3367 &lunsignedp, &lvolatilep, false);
3368 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
3369 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
3374 /* If this is not a constant, we can only do something if bit positions,
3375 sizes, and signedness are the same. */
3376 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
3377 &runsignedp, &rvolatilep, false);
3379 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
3380 || lunsignedp != runsignedp || offset != 0
3381 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
3385 /* See if we can find a mode to refer to this field. We should be able to,
3386 but fail if we can't. */
3388 && GET_MODE_BITSIZE (lmode) > 0
3389 && flag_strict_volatile_bitfields > 0)
3392 nmode = get_best_mode (lbitsize, lbitpos, 0, 0,
3393 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
3394 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
3395 TYPE_ALIGN (TREE_TYPE (rinner))),
3396 word_mode, lvolatilep || rvolatilep);
3397 if (nmode == VOIDmode)
3400 /* Set signed and unsigned types of the precision of this mode for the
3402 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
3403 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
3405 /* Compute the bit position and size for the new reference and our offset
3406 within it. If the new reference is the same size as the original, we
3407 won't optimize anything, so return zero. */
3408 nbitsize = GET_MODE_BITSIZE (nmode);
3409 nbitpos = lbitpos & ~ (nbitsize - 1);
3411 if (nbitsize == lbitsize)
3414 if (BYTES_BIG_ENDIAN)
3415 lbitpos = nbitsize - lbitsize - lbitpos;
3417 /* Make the mask to be used against the extracted field. */
3418 mask = build_int_cst_type (unsigned_type, -1);
3419 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize));
3420 mask = const_binop (RSHIFT_EXPR, mask,
3421 size_int (nbitsize - lbitsize - lbitpos));
3424 /* If not comparing with constant, just rework the comparison
3426 return fold_build2_loc (loc, code, compare_type,
3427 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3428 make_bit_field_ref (loc, linner,
3433 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3434 make_bit_field_ref (loc, rinner,
3440 /* Otherwise, we are handling the constant case. See if the constant is too
3441 big for the field. Warn and return a tree of for 0 (false) if so. We do
3442 this not only for its own sake, but to avoid having to test for this
3443 error case below. If we didn't, we might generate wrong code.
3445 For unsigned fields, the constant shifted right by the field length should
3446 be all zero. For signed fields, the high-order bits should agree with
3451 if (! integer_zerop (const_binop (RSHIFT_EXPR,
3452 fold_convert_loc (loc,
3453 unsigned_type, rhs),
3454 size_int (lbitsize))))
3456 warning (0, "comparison is always %d due to width of bit-field",
3458 return constant_boolean_node (code == NE_EXPR, compare_type);
3463 tree tem = const_binop (RSHIFT_EXPR,
3464 fold_convert_loc (loc, signed_type, rhs),
3465 size_int (lbitsize - 1));
3466 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
3468 warning (0, "comparison is always %d due to width of bit-field",
3470 return constant_boolean_node (code == NE_EXPR, compare_type);
3474 /* Single-bit compares should always be against zero. */
3475 if (lbitsize == 1 && ! integer_zerop (rhs))
3477 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
3478 rhs = build_int_cst (type, 0);
3481 /* Make a new bitfield reference, shift the constant over the
3482 appropriate number of bits and mask it with the computed mask
3483 (in case this was a signed field). If we changed it, make a new one. */
3484 lhs = make_bit_field_ref (loc, linner, unsigned_type, nbitsize, nbitpos, 1);
3487 TREE_SIDE_EFFECTS (lhs) = 1;
3488 TREE_THIS_VOLATILE (lhs) = 1;
3491 rhs = const_binop (BIT_AND_EXPR,
3492 const_binop (LSHIFT_EXPR,
3493 fold_convert_loc (loc, unsigned_type, rhs),
3494 size_int (lbitpos)),
3497 lhs = build2_loc (loc, code, compare_type,
3498 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask), rhs);
3502 /* Subroutine for fold_truth_andor_1: decode a field reference.
3504 If EXP is a comparison reference, we return the innermost reference.
3506 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
3507 set to the starting bit number.
3509 If the innermost field can be completely contained in a mode-sized
3510 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
3512 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
3513 otherwise it is not changed.
3515 *PUNSIGNEDP is set to the signedness of the field.
3517 *PMASK is set to the mask used. This is either contained in a
3518 BIT_AND_EXPR or derived from the width of the field.
3520 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
3522 Return 0 if this is not a component reference or is one that we can't
3523 do anything with. */
3526 decode_field_reference (location_t loc, tree exp, HOST_WIDE_INT *pbitsize,
3527 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
3528 int *punsignedp, int *pvolatilep,
3529 tree *pmask, tree *pand_mask)
3531 tree outer_type = 0;
3533 tree mask, inner, offset;
3535 unsigned int precision;
3537 /* All the optimizations using this function assume integer fields.
3538 There are problems with FP fields since the type_for_size call
3539 below can fail for, e.g., XFmode. */
3540 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
3543 /* We are interested in the bare arrangement of bits, so strip everything
3544 that doesn't affect the machine mode. However, record the type of the
3545 outermost expression if it may matter below. */
3546 if (CONVERT_EXPR_P (exp)
3547 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3548 outer_type = TREE_TYPE (exp);
3551 if (TREE_CODE (exp) == BIT_AND_EXPR)
3553 and_mask = TREE_OPERAND (exp, 1);
3554 exp = TREE_OPERAND (exp, 0);
3555 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
3556 if (TREE_CODE (and_mask) != INTEGER_CST)
3560 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
3561 punsignedp, pvolatilep, false);
3562 if ((inner == exp && and_mask == 0)
3563 || *pbitsize < 0 || offset != 0
3564 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
3567 /* If the number of bits in the reference is the same as the bitsize of
3568 the outer type, then the outer type gives the signedness. Otherwise
3569 (in case of a small bitfield) the signedness is unchanged. */
3570 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
3571 *punsignedp = TYPE_UNSIGNED (outer_type);
3573 /* Compute the mask to access the bitfield. */
3574 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
3575 precision = TYPE_PRECISION (unsigned_type);
3577 mask = build_int_cst_type (unsigned_type, -1);
3579 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3580 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3582 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
3584 mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3585 fold_convert_loc (loc, unsigned_type, and_mask), mask);
3588 *pand_mask = and_mask;
3592 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
3596 all_ones_mask_p (const_tree mask, int size)
3598 tree type = TREE_TYPE (mask);
3599 unsigned int precision = TYPE_PRECISION (type);
3602 tmask = build_int_cst_type (signed_type_for (type), -1);
3605 tree_int_cst_equal (mask,
3606 const_binop (RSHIFT_EXPR,
3607 const_binop (LSHIFT_EXPR, tmask,
3608 size_int (precision - size)),
3609 size_int (precision - size)));
3612 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
3613 represents the sign bit of EXP's type. If EXP represents a sign
3614 or zero extension, also test VAL against the unextended type.
3615 The return value is the (sub)expression whose sign bit is VAL,
3616 or NULL_TREE otherwise. */
3619 sign_bit_p (tree exp, const_tree val)
3621 unsigned HOST_WIDE_INT mask_lo, lo;
3622 HOST_WIDE_INT mask_hi, hi;
3626 /* Tree EXP must have an integral type. */
3627 t = TREE_TYPE (exp);
3628 if (! INTEGRAL_TYPE_P (t))
3631 /* Tree VAL must be an integer constant. */
3632 if (TREE_CODE (val) != INTEGER_CST
3633 || TREE_OVERFLOW (val))
3636 width = TYPE_PRECISION (t);
3637 if (width > HOST_BITS_PER_WIDE_INT)
3639 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
3642 mask_hi = ((unsigned HOST_WIDE_INT) -1
3643 >> (2 * HOST_BITS_PER_WIDE_INT - width));
3649 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
3652 mask_lo = ((unsigned HOST_WIDE_INT) -1
3653 >> (HOST_BITS_PER_WIDE_INT - width));
3656 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
3657 treat VAL as if it were unsigned. */
3658 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
3659 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
3662 /* Handle extension from a narrower type. */
3663 if (TREE_CODE (exp) == NOP_EXPR
3664 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
3665 return sign_bit_p (TREE_OPERAND (exp, 0), val);
3670 /* Subroutine for fold_truth_andor_1: determine if an operand is simple enough
3671 to be evaluated unconditionally. */
3674 simple_operand_p (const_tree exp)
3676 /* Strip any conversions that don't change the machine mode. */
3679 return (CONSTANT_CLASS_P (exp)
3680 || TREE_CODE (exp) == SSA_NAME
3682 && ! TREE_ADDRESSABLE (exp)
3683 && ! TREE_THIS_VOLATILE (exp)
3684 && ! DECL_NONLOCAL (exp)
3685 /* Don't regard global variables as simple. They may be
3686 allocated in ways unknown to the compiler (shared memory,
3687 #pragma weak, etc). */
3688 && ! TREE_PUBLIC (exp)
3689 && ! DECL_EXTERNAL (exp)
3690 /* Loading a static variable is unduly expensive, but global
3691 registers aren't expensive. */
3692 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
3695 /* Subroutine for fold_truth_andor: determine if an operand is simple enough
3696 to be evaluated unconditionally.
3697 I addition to simple_operand_p, we assume that comparisons, conversions,
3698 and logic-not operations are simple, if their operands are simple, too. */
3701 simple_operand_p_2 (tree exp)
3703 enum tree_code code;
3705 if (TREE_SIDE_EFFECTS (exp)
3706 || tree_could_trap_p (exp))
3709 while (CONVERT_EXPR_P (exp))
3710 exp = TREE_OPERAND (exp, 0);
3712 code = TREE_CODE (exp);
3714 if (TREE_CODE_CLASS (code) == tcc_comparison)
3715 return (simple_operand_p (TREE_OPERAND (exp, 0))
3716 && simple_operand_p (TREE_OPERAND (exp, 1)));
3718 if (code == TRUTH_NOT_EXPR)
3719 return simple_operand_p_2 (TREE_OPERAND (exp, 0));
3721 return simple_operand_p (exp);
3725 /* The following functions are subroutines to fold_range_test and allow it to
3726 try to change a logical combination of comparisons into a range test.
3729 X == 2 || X == 3 || X == 4 || X == 5
3733 (unsigned) (X - 2) <= 3
3735 We describe each set of comparisons as being either inside or outside
3736 a range, using a variable named like IN_P, and then describe the
3737 range with a lower and upper bound. If one of the bounds is omitted,
3738 it represents either the highest or lowest value of the type.
3740 In the comments below, we represent a range by two numbers in brackets
3741 preceded by a "+" to designate being inside that range, or a "-" to
3742 designate being outside that range, so the condition can be inverted by
3743 flipping the prefix. An omitted bound is represented by a "-". For
3744 example, "- [-, 10]" means being outside the range starting at the lowest
3745 possible value and ending at 10, in other words, being greater than 10.
3746 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
3749 We set up things so that the missing bounds are handled in a consistent
3750 manner so neither a missing bound nor "true" and "false" need to be
3751 handled using a special case. */
3753 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
3754 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
3755 and UPPER1_P are nonzero if the respective argument is an upper bound
3756 and zero for a lower. TYPE, if nonzero, is the type of the result; it
3757 must be specified for a comparison. ARG1 will be converted to ARG0's
3758 type if both are specified. */
3761 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
3762 tree arg1, int upper1_p)
3768 /* If neither arg represents infinity, do the normal operation.
3769 Else, if not a comparison, return infinity. Else handle the special
3770 comparison rules. Note that most of the cases below won't occur, but
3771 are handled for consistency. */
3773 if (arg0 != 0 && arg1 != 0)
3775 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
3776 arg0, fold_convert (TREE_TYPE (arg0), arg1));
3778 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
3781 if (TREE_CODE_CLASS (code) != tcc_comparison)
3784 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
3785 for neither. In real maths, we cannot assume open ended ranges are
3786 the same. But, this is computer arithmetic, where numbers are finite.
3787 We can therefore make the transformation of any unbounded range with
3788 the value Z, Z being greater than any representable number. This permits
3789 us to treat unbounded ranges as equal. */
3790 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
3791 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
3795 result = sgn0 == sgn1;
3798 result = sgn0 != sgn1;
3801 result = sgn0 < sgn1;
3804 result = sgn0 <= sgn1;
3807 result = sgn0 > sgn1;
3810 result = sgn0 >= sgn1;
3816 return constant_boolean_node (result, type);
3819 /* Helper routine for make_range. Perform one step for it, return
3820 new expression if the loop should continue or NULL_TREE if it should
3824 make_range_step (location_t loc, enum tree_code code, tree arg0, tree arg1,
3825 tree exp_type, tree *p_low, tree *p_high, int *p_in_p,
3826 bool *strict_overflow_p)
3828 tree arg0_type = TREE_TYPE (arg0);
3829 tree n_low, n_high, low = *p_low, high = *p_high;
3830 int in_p = *p_in_p, n_in_p;
3834 case TRUTH_NOT_EXPR:
3835 /* We can only do something if the range is testing for zero. */
3836 if (low == NULL_TREE || high == NULL_TREE
3837 || ! integer_zerop (low) || ! integer_zerop (high))
3842 case EQ_EXPR: case NE_EXPR:
3843 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
3844 /* We can only do something if the range is testing for zero
3845 and if the second operand is an integer constant. Note that
3846 saying something is "in" the range we make is done by
3847 complementing IN_P since it will set in the initial case of
3848 being not equal to zero; "out" is leaving it alone. */
3849 if (low == NULL_TREE || high == NULL_TREE
3850 || ! integer_zerop (low) || ! integer_zerop (high)
3851 || TREE_CODE (arg1) != INTEGER_CST)
3856 case NE_EXPR: /* - [c, c] */
3859 case EQ_EXPR: /* + [c, c] */
3860 in_p = ! in_p, low = high = arg1;
3862 case GT_EXPR: /* - [-, c] */
3863 low = 0, high = arg1;
3865 case GE_EXPR: /* + [c, -] */
3866 in_p = ! in_p, low = arg1, high = 0;
3868 case LT_EXPR: /* - [c, -] */
3869 low = arg1, high = 0;
3871 case LE_EXPR: /* + [-, c] */
3872 in_p = ! in_p, low = 0, high = arg1;
3878 /* If this is an unsigned comparison, we also know that EXP is
3879 greater than or equal to zero. We base the range tests we make
3880 on that fact, so we record it here so we can parse existing
3881 range tests. We test arg0_type since often the return type
3882 of, e.g. EQ_EXPR, is boolean. */
3883 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
3885 if (! merge_ranges (&n_in_p, &n_low, &n_high,
3887 build_int_cst (arg0_type, 0),
3891 in_p = n_in_p, low = n_low, high = n_high;
3893 /* If the high bound is missing, but we have a nonzero low
3894 bound, reverse the range so it goes from zero to the low bound
3896 if (high == 0 && low && ! integer_zerop (low))
3899 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
3900 integer_one_node, 0);
3901 low = build_int_cst (arg0_type, 0);
3911 /* If flag_wrapv and ARG0_TYPE is signed, make sure
3912 low and high are non-NULL, then normalize will DTRT. */
3913 if (!TYPE_UNSIGNED (arg0_type)
3914 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
3916 if (low == NULL_TREE)
3917 low = TYPE_MIN_VALUE (arg0_type);
3918 if (high == NULL_TREE)
3919 high = TYPE_MAX_VALUE (arg0_type);
3922 /* (-x) IN [a,b] -> x in [-b, -a] */
3923 n_low = range_binop (MINUS_EXPR, exp_type,
3924 build_int_cst (exp_type, 0),
3926 n_high = range_binop (MINUS_EXPR, exp_type,
3927 build_int_cst (exp_type, 0),
3929 if (n_high != 0 && TREE_OVERFLOW (n_high))
3935 return build2_loc (loc, MINUS_EXPR, exp_type, negate_expr (arg0),
3936 build_int_cst (exp_type, 1));
3940 if (TREE_CODE (arg1) != INTEGER_CST)
3943 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
3944 move a constant to the other side. */
3945 if (!TYPE_UNSIGNED (arg0_type)
3946 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
3949 /* If EXP is signed, any overflow in the computation is undefined,
3950 so we don't worry about it so long as our computations on
3951 the bounds don't overflow. For unsigned, overflow is defined
3952 and this is exactly the right thing. */
3953 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
3954 arg0_type, low, 0, arg1, 0);
3955 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
3956 arg0_type, high, 1, arg1, 0);
3957 if ((n_low != 0 && TREE_OVERFLOW (n_low))
3958 || (n_high != 0 && TREE_OVERFLOW (n_high)))
3961 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
3962 *strict_overflow_p = true;
3965 /* Check for an unsigned range which has wrapped around the maximum
3966 value thus making n_high < n_low, and normalize it. */
3967 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
3969 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
3970 integer_one_node, 0);
3971 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
3972 integer_one_node, 0);
3974 /* If the range is of the form +/- [ x+1, x ], we won't
3975 be able to normalize it. But then, it represents the
3976 whole range or the empty set, so make it
3978 if (tree_int_cst_equal (n_low, low)
3979 && tree_int_cst_equal (n_high, high))
3985 low = n_low, high = n_high;
3993 case NON_LVALUE_EXPR:
3994 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
3997 if (! INTEGRAL_TYPE_P (arg0_type)
3998 || (low != 0 && ! int_fits_type_p (low, arg0_type))
3999 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4002 n_low = low, n_high = high;
4005 n_low = fold_convert_loc (loc, arg0_type, n_low);
4008 n_high = fold_convert_loc (loc, arg0_type, n_high);
4010 /* If we're converting arg0 from an unsigned type, to exp,
4011 a signed type, we will be doing the comparison as unsigned.
4012 The tests above have already verified that LOW and HIGH
4015 So we have to ensure that we will handle large unsigned
4016 values the same way that the current signed bounds treat
4019 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4023 /* For fixed-point modes, we need to pass the saturating flag
4024 as the 2nd parameter. */
4025 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4027 = lang_hooks.types.type_for_mode (TYPE_MODE (arg0_type),
4028 TYPE_SATURATING (arg0_type));
4031 = lang_hooks.types.type_for_mode (TYPE_MODE (arg0_type), 1);
4033 /* A range without an upper bound is, naturally, unbounded.
4034 Since convert would have cropped a very large value, use
4035 the max value for the destination type. */
4037 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4038 : TYPE_MAX_VALUE (arg0_type);
4040 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4041 high_positive = fold_build2_loc (loc, RSHIFT_EXPR, arg0_type,
4042 fold_convert_loc (loc, arg0_type,
4044 build_int_cst (arg0_type, 1));
4046 /* If the low bound is specified, "and" the range with the
4047 range for which the original unsigned value will be
4051 if (! merge_ranges (&n_in_p, &n_low, &n_high, 1, n_low, n_high,
4052 1, fold_convert_loc (loc, arg0_type,
4057 in_p = (n_in_p == in_p);
4061 /* Otherwise, "or" the range with the range of the input
4062 that will be interpreted as negative. */
4063 if (! merge_ranges (&n_in_p, &n_low, &n_high, 0, n_low, n_high,
4064 1, fold_convert_loc (loc, arg0_type,
4069 in_p = (in_p != n_in_p);
4083 /* Given EXP, a logical expression, set the range it is testing into
4084 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4085 actually being tested. *PLOW and *PHIGH will be made of the same
4086 type as the returned expression. If EXP is not a comparison, we
4087 will most likely not be returning a useful value and range. Set
4088 *STRICT_OVERFLOW_P to true if the return value is only valid
4089 because signed overflow is undefined; otherwise, do not change
4090 *STRICT_OVERFLOW_P. */
4093 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4094 bool *strict_overflow_p)
4096 enum tree_code code;
4097 tree arg0, arg1 = NULL_TREE;
4098 tree exp_type, nexp;
4101 location_t loc = EXPR_LOCATION (exp);
4103 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4104 and see if we can refine the range. Some of the cases below may not
4105 happen, but it doesn't seem worth worrying about this. We "continue"
4106 the outer loop when we've changed something; otherwise we "break"
4107 the switch, which will "break" the while. */
4110 low = high = build_int_cst (TREE_TYPE (exp), 0);
4114 code = TREE_CODE (exp);
4115 exp_type = TREE_TYPE (exp);
4118 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4120 if (TREE_OPERAND_LENGTH (exp) > 0)
4121 arg0 = TREE_OPERAND (exp, 0);
4122 if (TREE_CODE_CLASS (code) == tcc_binary
4123 || TREE_CODE_CLASS (code) == tcc_comparison
4124 || (TREE_CODE_CLASS (code) == tcc_expression
4125 && TREE_OPERAND_LENGTH (exp) > 1))
4126 arg1 = TREE_OPERAND (exp, 1);
4128 if (arg0 == NULL_TREE)
4131 nexp = make_range_step (loc, code, arg0, arg1, exp_type, &low,
4132 &high, &in_p, strict_overflow_p);
4133 if (nexp == NULL_TREE)
4138 /* If EXP is a constant, we can evaluate whether this is true or false. */
4139 if (TREE_CODE (exp) == INTEGER_CST)
4141 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4143 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4149 *pin_p = in_p, *plow = low, *phigh = high;
4153 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4154 type, TYPE, return an expression to test if EXP is in (or out of, depending
4155 on IN_P) the range. Return 0 if the test couldn't be created. */
4158 build_range_check (location_t loc, tree type, tree exp, int in_p,
4159 tree low, tree high)
4161 tree etype = TREE_TYPE (exp), value;
4163 #ifdef HAVE_canonicalize_funcptr_for_compare
4164 /* Disable this optimization for function pointer expressions
4165 on targets that require function pointer canonicalization. */
4166 if (HAVE_canonicalize_funcptr_for_compare
4167 && TREE_CODE (etype) == POINTER_TYPE
4168 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4174 value = build_range_check (loc, type, exp, 1, low, high);
4176 return invert_truthvalue_loc (loc, value);
4181 if (low == 0 && high == 0)
4182 return build_int_cst (type, 1);
4185 return fold_build2_loc (loc, LE_EXPR, type, exp,
4186 fold_convert_loc (loc, etype, high));
4189 return fold_build2_loc (loc, GE_EXPR, type, exp,
4190 fold_convert_loc (loc, etype, low));
4192 if (operand_equal_p (low, high, 0))
4193 return fold_build2_loc (loc, EQ_EXPR, type, exp,
4194 fold_convert_loc (loc, etype, low));
4196 if (integer_zerop (low))
4198 if (! TYPE_UNSIGNED (etype))
4200 etype = unsigned_type_for (etype);
4201 high = fold_convert_loc (loc, etype, high);
4202 exp = fold_convert_loc (loc, etype, exp);
4204 return build_range_check (loc, type, exp, 1, 0, high);
4207 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4208 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4210 unsigned HOST_WIDE_INT lo;
4214 prec = TYPE_PRECISION (etype);
4215 if (prec <= HOST_BITS_PER_WIDE_INT)
4218 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4222 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4223 lo = (unsigned HOST_WIDE_INT) -1;
4226 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4228 if (TYPE_UNSIGNED (etype))
4230 tree signed_etype = signed_type_for (etype);
4231 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4233 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4235 etype = signed_etype;
4236 exp = fold_convert_loc (loc, etype, exp);
4238 return fold_build2_loc (loc, GT_EXPR, type, exp,
4239 build_int_cst (etype, 0));
4243 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4244 This requires wrap-around arithmetics for the type of the expression.
4245 First make sure that arithmetics in this type is valid, then make sure
4246 that it wraps around. */
4247 if (TREE_CODE (etype) == ENUMERAL_TYPE || TREE_CODE (etype) == BOOLEAN_TYPE)
4248 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4249 TYPE_UNSIGNED (etype));
4251 if (TREE_CODE (etype) == INTEGER_TYPE && !TYPE_OVERFLOW_WRAPS (etype))
4253 tree utype, minv, maxv;
4255 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4256 for the type in question, as we rely on this here. */
4257 utype = unsigned_type_for (etype);
4258 maxv = fold_convert_loc (loc, utype, TYPE_MAX_VALUE (etype));
4259 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4260 integer_one_node, 1);
4261 minv = fold_convert_loc (loc, utype, TYPE_MIN_VALUE (etype));
4263 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4270 high = fold_convert_loc (loc, etype, high);
4271 low = fold_convert_loc (loc, etype, low);
4272 exp = fold_convert_loc (loc, etype, exp);
4274 value = const_binop (MINUS_EXPR, high, low);
4277 if (POINTER_TYPE_P (etype))
4279 if (value != 0 && !TREE_OVERFLOW (value))
4281 low = fold_build1_loc (loc, NEGATE_EXPR, TREE_TYPE (low), low);
4282 return build_range_check (loc, type,
4283 fold_build_pointer_plus_loc (loc, exp, low),
4284 1, build_int_cst (etype, 0), value);
4289 if (value != 0 && !TREE_OVERFLOW (value))
4290 return build_range_check (loc, type,
4291 fold_build2_loc (loc, MINUS_EXPR, etype, exp, low),
4292 1, build_int_cst (etype, 0), value);
4297 /* Return the predecessor of VAL in its type, handling the infinite case. */
4300 range_predecessor (tree val)
4302 tree type = TREE_TYPE (val);
4304 if (INTEGRAL_TYPE_P (type)
4305 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4308 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4311 /* Return the successor of VAL in its type, handling the infinite case. */
4314 range_successor (tree val)
4316 tree type = TREE_TYPE (val);
4318 if (INTEGRAL_TYPE_P (type)
4319 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4322 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4325 /* Given two ranges, see if we can merge them into one. Return 1 if we
4326 can, 0 if we can't. Set the output range into the specified parameters. */
4329 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4330 tree high0, int in1_p, tree low1, tree high1)
4338 int lowequal = ((low0 == 0 && low1 == 0)
4339 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4340 low0, 0, low1, 0)));
4341 int highequal = ((high0 == 0 && high1 == 0)
4342 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4343 high0, 1, high1, 1)));
4345 /* Make range 0 be the range that starts first, or ends last if they
4346 start at the same value. Swap them if it isn't. */
4347 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4350 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4351 high1, 1, high0, 1))))
4353 temp = in0_p, in0_p = in1_p, in1_p = temp;
4354 tem = low0, low0 = low1, low1 = tem;
4355 tem = high0, high0 = high1, high1 = tem;
4358 /* Now flag two cases, whether the ranges are disjoint or whether the
4359 second range is totally subsumed in the first. Note that the tests
4360 below are simplified by the ones above. */
4361 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4362 high0, 1, low1, 0));
4363 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4364 high1, 1, high0, 1));
4366 /* We now have four cases, depending on whether we are including or
4367 excluding the two ranges. */
4370 /* If they don't overlap, the result is false. If the second range
4371 is a subset it is the result. Otherwise, the range is from the start
4372 of the second to the end of the first. */
4374 in_p = 0, low = high = 0;
4376 in_p = 1, low = low1, high = high1;
4378 in_p = 1, low = low1, high = high0;
4381 else if (in0_p && ! in1_p)
4383 /* If they don't overlap, the result is the first range. If they are
4384 equal, the result is false. If the second range is a subset of the
4385 first, and the ranges begin at the same place, we go from just after
4386 the end of the second range to the end of the first. If the second
4387 range is not a subset of the first, or if it is a subset and both
4388 ranges end at the same place, the range starts at the start of the
4389 first range and ends just before the second range.
4390 Otherwise, we can't describe this as a single range. */
4392 in_p = 1, low = low0, high = high0;
4393 else if (lowequal && highequal)
4394 in_p = 0, low = high = 0;
4395 else if (subset && lowequal)
4397 low = range_successor (high1);
4402 /* We are in the weird situation where high0 > high1 but
4403 high1 has no successor. Punt. */
4407 else if (! subset || highequal)
4410 high = range_predecessor (low1);
4414 /* low0 < low1 but low1 has no predecessor. Punt. */
4422 else if (! in0_p && in1_p)
4424 /* If they don't overlap, the result is the second range. If the second
4425 is a subset of the first, the result is false. Otherwise,
4426 the range starts just after the first range and ends at the
4427 end of the second. */
4429 in_p = 1, low = low1, high = high1;
4430 else if (subset || highequal)
4431 in_p = 0, low = high = 0;
4434 low = range_successor (high0);
4439 /* high1 > high0 but high0 has no successor. Punt. */
4447 /* The case where we are excluding both ranges. Here the complex case
4448 is if they don't overlap. In that case, the only time we have a
4449 range is if they are adjacent. If the second is a subset of the
4450 first, the result is the first. Otherwise, the range to exclude
4451 starts at the beginning of the first range and ends at the end of the
4455 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4456 range_successor (high0),
4458 in_p = 0, low = low0, high = high1;
4461 /* Canonicalize - [min, x] into - [-, x]. */
4462 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4463 switch (TREE_CODE (TREE_TYPE (low0)))
4466 if (TYPE_PRECISION (TREE_TYPE (low0))
4467 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
4471 if (tree_int_cst_equal (low0,
4472 TYPE_MIN_VALUE (TREE_TYPE (low0))))
4476 if (TYPE_UNSIGNED (TREE_TYPE (low0))
4477 && integer_zerop (low0))
4484 /* Canonicalize - [x, max] into - [x, -]. */
4485 if (high1 && TREE_CODE (high1) == INTEGER_CST)
4486 switch (TREE_CODE (TREE_TYPE (high1)))
4489 if (TYPE_PRECISION (TREE_TYPE (high1))
4490 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
4494 if (tree_int_cst_equal (high1,
4495 TYPE_MAX_VALUE (TREE_TYPE (high1))))
4499 if (TYPE_UNSIGNED (TREE_TYPE (high1))
4500 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
4502 integer_one_node, 1)))
4509 /* The ranges might be also adjacent between the maximum and
4510 minimum values of the given type. For
4511 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4512 return + [x + 1, y - 1]. */
4513 if (low0 == 0 && high1 == 0)
4515 low = range_successor (high0);
4516 high = range_predecessor (low1);
4517 if (low == 0 || high == 0)
4527 in_p = 0, low = low0, high = high0;
4529 in_p = 0, low = low0, high = high1;
4532 *pin_p = in_p, *plow = low, *phigh = high;
4537 /* Subroutine of fold, looking inside expressions of the form
4538 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
4539 of the COND_EXPR. This function is being used also to optimize
4540 A op B ? C : A, by reversing the comparison first.
4542 Return a folded expression whose code is not a COND_EXPR
4543 anymore, or NULL_TREE if no folding opportunity is found. */
4546 fold_cond_expr_with_comparison (location_t loc, tree type,
4547 tree arg0, tree arg1, tree arg2)
4549 enum tree_code comp_code = TREE_CODE (arg0);
4550 tree arg00 = TREE_OPERAND (arg0, 0);
4551 tree arg01 = TREE_OPERAND (arg0, 1);
4552 tree arg1_type = TREE_TYPE (arg1);
4558 /* If we have A op 0 ? A : -A, consider applying the following
4561 A == 0? A : -A same as -A
4562 A != 0? A : -A same as A
4563 A >= 0? A : -A same as abs (A)
4564 A > 0? A : -A same as abs (A)
4565 A <= 0? A : -A same as -abs (A)
4566 A < 0? A : -A same as -abs (A)
4568 None of these transformations work for modes with signed
4569 zeros. If A is +/-0, the first two transformations will
4570 change the sign of the result (from +0 to -0, or vice
4571 versa). The last four will fix the sign of the result,
4572 even though the original expressions could be positive or
4573 negative, depending on the sign of A.
4575 Note that all these transformations are correct if A is
4576 NaN, since the two alternatives (A and -A) are also NaNs. */
4577 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4578 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
4579 ? real_zerop (arg01)
4580 : integer_zerop (arg01))
4581 && ((TREE_CODE (arg2) == NEGATE_EXPR
4582 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
4583 /* In the case that A is of the form X-Y, '-A' (arg2) may
4584 have already been folded to Y-X, check for that. */
4585 || (TREE_CODE (arg1) == MINUS_EXPR
4586 && TREE_CODE (arg2) == MINUS_EXPR
4587 && operand_equal_p (TREE_OPERAND (arg1, 0),
4588 TREE_OPERAND (arg2, 1), 0)
4589 && operand_equal_p (TREE_OPERAND (arg1, 1),
4590 TREE_OPERAND (arg2, 0), 0))))
4595 tem = fold_convert_loc (loc, arg1_type, arg1);
4596 return pedantic_non_lvalue_loc (loc,
4597 fold_convert_loc (loc, type,
4598 negate_expr (tem)));
4601 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4604 if (flag_trapping_math)
4609 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4610 arg1 = fold_convert_loc (loc, signed_type_for
4611 (TREE_TYPE (arg1)), arg1);
4612 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4613 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4616 if (flag_trapping_math)
4620 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4621 arg1 = fold_convert_loc (loc, signed_type_for
4622 (TREE_TYPE (arg1)), arg1);
4623 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4624 return negate_expr (fold_convert_loc (loc, type, tem));
4626 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4630 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
4631 A == 0 ? A : 0 is always 0 unless A is -0. Note that
4632 both transformations are correct when A is NaN: A != 0
4633 is then true, and A == 0 is false. */
4635 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4636 && integer_zerop (arg01) && integer_zerop (arg2))
4638 if (comp_code == NE_EXPR)
4639 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4640 else if (comp_code == EQ_EXPR)
4641 return build_int_cst (type, 0);
4644 /* Try some transformations of A op B ? A : B.
4646 A == B? A : B same as B
4647 A != B? A : B same as A
4648 A >= B? A : B same as max (A, B)
4649 A > B? A : B same as max (B, A)
4650 A <= B? A : B same as min (A, B)
4651 A < B? A : B same as min (B, A)
4653 As above, these transformations don't work in the presence
4654 of signed zeros. For example, if A and B are zeros of
4655 opposite sign, the first two transformations will change
4656 the sign of the result. In the last four, the original
4657 expressions give different results for (A=+0, B=-0) and
4658 (A=-0, B=+0), but the transformed expressions do not.
4660 The first two transformations are correct if either A or B
4661 is a NaN. In the first transformation, the condition will
4662 be false, and B will indeed be chosen. In the case of the
4663 second transformation, the condition A != B will be true,
4664 and A will be chosen.
4666 The conversions to max() and min() are not correct if B is
4667 a number and A is not. The conditions in the original
4668 expressions will be false, so all four give B. The min()
4669 and max() versions would give a NaN instead. */
4670 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4671 && operand_equal_for_comparison_p (arg01, arg2, arg00)
4672 /* Avoid these transformations if the COND_EXPR may be used
4673 as an lvalue in the C++ front-end. PR c++/19199. */
4675 || (strcmp (lang_hooks.name, "GNU C++") != 0
4676 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
4677 || ! maybe_lvalue_p (arg1)
4678 || ! maybe_lvalue_p (arg2)))
4680 tree comp_op0 = arg00;
4681 tree comp_op1 = arg01;
4682 tree comp_type = TREE_TYPE (comp_op0);
4684 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
4685 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
4695 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg2));
4697 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4702 /* In C++ a ?: expression can be an lvalue, so put the
4703 operand which will be used if they are equal first
4704 so that we can convert this back to the
4705 corresponding COND_EXPR. */
4706 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4708 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4709 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4710 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
4711 ? fold_build2_loc (loc, MIN_EXPR, comp_type, comp_op0, comp_op1)
4712 : fold_build2_loc (loc, MIN_EXPR, comp_type,
4713 comp_op1, comp_op0);
4714 return pedantic_non_lvalue_loc (loc,
4715 fold_convert_loc (loc, type, tem));
4722 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4724 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4725 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4726 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
4727 ? fold_build2_loc (loc, MAX_EXPR, comp_type, comp_op0, comp_op1)
4728 : fold_build2_loc (loc, MAX_EXPR, comp_type,
4729 comp_op1, comp_op0);
4730 return pedantic_non_lvalue_loc (loc,
4731 fold_convert_loc (loc, type, tem));
4735 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4736 return pedantic_non_lvalue_loc (loc,
4737 fold_convert_loc (loc, type, arg2));
4740 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4741 return pedantic_non_lvalue_loc (loc,
4742 fold_convert_loc (loc, type, arg1));
4745 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4750 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
4751 we might still be able to simplify this. For example,
4752 if C1 is one less or one more than C2, this might have started
4753 out as a MIN or MAX and been transformed by this function.
4754 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
4756 if (INTEGRAL_TYPE_P (type)
4757 && TREE_CODE (arg01) == INTEGER_CST
4758 && TREE_CODE (arg2) == INTEGER_CST)
4762 if (TREE_CODE (arg1) == INTEGER_CST)
4764 /* We can replace A with C1 in this case. */
4765 arg1 = fold_convert_loc (loc, type, arg01);
4766 return fold_build3_loc (loc, COND_EXPR, type, arg0, arg1, arg2);
4769 /* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
4770 MIN_EXPR, to preserve the signedness of the comparison. */
4771 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4773 && operand_equal_p (arg01,
4774 const_binop (PLUS_EXPR, arg2,
4775 build_int_cst (type, 1)),
4778 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4779 fold_convert_loc (loc, TREE_TYPE (arg00),
4781 return pedantic_non_lvalue_loc (loc,
4782 fold_convert_loc (loc, type, tem));
4787 /* If C1 is C2 - 1, this is min(A, C2), with the same care
4789 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4791 && operand_equal_p (arg01,
4792 const_binop (MINUS_EXPR, arg2,
4793 build_int_cst (type, 1)),
4796 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4797 fold_convert_loc (loc, TREE_TYPE (arg00),
4799 return pedantic_non_lvalue_loc (loc,
4800 fold_convert_loc (loc, type, tem));
4805 /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for
4806 MAX_EXPR, to preserve the signedness of the comparison. */
4807 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4809 && operand_equal_p (arg01,
4810 const_binop (MINUS_EXPR, arg2,
4811 build_int_cst (type, 1)),
4814 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4815 fold_convert_loc (loc, TREE_TYPE (arg00),
4817 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4822 /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */
4823 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4825 && operand_equal_p (arg01,
4826 const_binop (PLUS_EXPR, arg2,
4827 build_int_cst (type, 1)),
4830 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4831 fold_convert_loc (loc, TREE_TYPE (arg00),
4833 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4847 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
4848 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
4849 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
4853 /* EXP is some logical combination of boolean tests. See if we can
4854 merge it into some range test. Return the new tree if so. */
4857 fold_range_test (location_t loc, enum tree_code code, tree type,
4860 int or_op = (code == TRUTH_ORIF_EXPR
4861 || code == TRUTH_OR_EXPR);
4862 int in0_p, in1_p, in_p;
4863 tree low0, low1, low, high0, high1, high;
4864 bool strict_overflow_p = false;
4865 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
4866 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
4868 const char * const warnmsg = G_("assuming signed overflow does not occur "
4869 "when simplifying range test");
4871 /* If this is an OR operation, invert both sides; we will invert
4872 again at the end. */
4874 in0_p = ! in0_p, in1_p = ! in1_p;
4876 /* If both expressions are the same, if we can merge the ranges, and we
4877 can build the range test, return it or it inverted. If one of the
4878 ranges is always true or always false, consider it to be the same
4879 expression as the other. */
4880 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
4881 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
4883 && 0 != (tem = (build_range_check (loc, type,
4885 : rhs != 0 ? rhs : integer_zero_node,
4888 if (strict_overflow_p)
4889 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
4890 return or_op ? invert_truthvalue_loc (loc, tem) : tem;
4893 /* On machines where the branch cost is expensive, if this is a
4894 short-circuited branch and the underlying object on both sides
4895 is the same, make a non-short-circuit operation. */
4896 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
4897 && lhs != 0 && rhs != 0
4898 && (code == TRUTH_ANDIF_EXPR
4899 || code == TRUTH_ORIF_EXPR)
4900 && operand_equal_p (lhs, rhs, 0))
4902 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
4903 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
4904 which cases we can't do this. */
4905 if (simple_operand_p (lhs))
4906 return build2_loc (loc, code == TRUTH_ANDIF_EXPR
4907 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4910 else if (!lang_hooks.decls.global_bindings_p ()
4911 && !CONTAINS_PLACEHOLDER_P (lhs))
4913 tree common = save_expr (lhs);
4915 if (0 != (lhs = build_range_check (loc, type, common,
4916 or_op ? ! in0_p : in0_p,
4918 && (0 != (rhs = build_range_check (loc, type, common,
4919 or_op ? ! in1_p : in1_p,
4922 if (strict_overflow_p)
4923 fold_overflow_warning (warnmsg,
4924 WARN_STRICT_OVERFLOW_COMPARISON);
4925 return build2_loc (loc, code == TRUTH_ANDIF_EXPR
4926 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4935 /* Subroutine for fold_truth_andor_1: C is an INTEGER_CST interpreted as a P
4936 bit value. Arrange things so the extra bits will be set to zero if and
4937 only if C is signed-extended to its full width. If MASK is nonzero,
4938 it is an INTEGER_CST that should be AND'ed with the extra bits. */
4941 unextend (tree c, int p, int unsignedp, tree mask)
4943 tree type = TREE_TYPE (c);
4944 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
4947 if (p == modesize || unsignedp)
4950 /* We work by getting just the sign bit into the low-order bit, then
4951 into the high-order bit, then sign-extend. We then XOR that value
4953 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1));
4954 temp = const_binop (BIT_AND_EXPR, temp, size_int (1));
4956 /* We must use a signed type in order to get an arithmetic right shift.
4957 However, we must also avoid introducing accidental overflows, so that
4958 a subsequent call to integer_zerop will work. Hence we must
4959 do the type conversion here. At this point, the constant is either
4960 zero or one, and the conversion to a signed type can never overflow.
4961 We could get an overflow if this conversion is done anywhere else. */
4962 if (TYPE_UNSIGNED (type))
4963 temp = fold_convert (signed_type_for (type), temp);
4965 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1));
4966 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1));
4968 temp = const_binop (BIT_AND_EXPR, temp,
4969 fold_convert (TREE_TYPE (c), mask));
4970 /* If necessary, convert the type back to match the type of C. */
4971 if (TYPE_UNSIGNED (type))
4972 temp = fold_convert (type, temp);
4974 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp));
4977 /* For an expression that has the form
4981 we can drop one of the inner expressions and simplify to
4985 LOC is the location of the resulting expression. OP is the inner
4986 logical operation; the left-hand side in the examples above, while CMPOP
4987 is the right-hand side. RHS_ONLY is used to prevent us from accidentally
4988 removing a condition that guards another, as in
4989 (A != NULL && A->...) || A == NULL
4990 which we must not transform. If RHS_ONLY is true, only eliminate the
4991 right-most operand of the inner logical operation. */
4994 merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop,
4997 tree type = TREE_TYPE (cmpop);
4998 enum tree_code code = TREE_CODE (cmpop);
4999 enum tree_code truthop_code = TREE_CODE (op);
5000 tree lhs = TREE_OPERAND (op, 0);
5001 tree rhs = TREE_OPERAND (op, 1);
5002 tree orig_lhs = lhs, orig_rhs = rhs;
5003 enum tree_code rhs_code = TREE_CODE (rhs);
5004 enum tree_code lhs_code = TREE_CODE (lhs);
5005 enum tree_code inv_code;
5007 if (TREE_SIDE_EFFECTS (op) || TREE_SIDE_EFFECTS (cmpop))
5010 if (TREE_CODE_CLASS (code) != tcc_comparison)
5013 if (rhs_code == truthop_code)
5015 tree newrhs = merge_truthop_with_opposite_arm (loc, rhs, cmpop, rhs_only);
5016 if (newrhs != NULL_TREE)
5019 rhs_code = TREE_CODE (rhs);
5022 if (lhs_code == truthop_code && !rhs_only)
5024 tree newlhs = merge_truthop_with_opposite_arm (loc, lhs, cmpop, false);
5025 if (newlhs != NULL_TREE)
5028 lhs_code = TREE_CODE (lhs);
5032 inv_code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (type)));
5033 if (inv_code == rhs_code
5034 && operand_equal_p (TREE_OPERAND (rhs, 0), TREE_OPERAND (cmpop, 0), 0)
5035 && operand_equal_p (TREE_OPERAND (rhs, 1), TREE_OPERAND (cmpop, 1), 0))
5037 if (!rhs_only && inv_code == lhs_code
5038 && operand_equal_p (TREE_OPERAND (lhs, 0), TREE_OPERAND (cmpop, 0), 0)
5039 && operand_equal_p (TREE_OPERAND (lhs, 1), TREE_OPERAND (cmpop, 1), 0))
5041 if (rhs != orig_rhs || lhs != orig_lhs)
5042 return fold_build2_loc (loc, truthop_code, TREE_TYPE (cmpop),
5047 /* Find ways of folding logical expressions of LHS and RHS:
5048 Try to merge two comparisons to the same innermost item.
5049 Look for range tests like "ch >= '0' && ch <= '9'".
5050 Look for combinations of simple terms on machines with expensive branches
5051 and evaluate the RHS unconditionally.
5053 For example, if we have p->a == 2 && p->b == 4 and we can make an
5054 object large enough to span both A and B, we can do this with a comparison
5055 against the object ANDed with the a mask.
5057 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5058 operations to do this with one comparison.
5060 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5061 function and the one above.
5063 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5064 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5066 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5069 We return the simplified tree or 0 if no optimization is possible. */
5072 fold_truth_andor_1 (location_t loc, enum tree_code code, tree truth_type,
5075 /* If this is the "or" of two comparisons, we can do something if
5076 the comparisons are NE_EXPR. If this is the "and", we can do something
5077 if the comparisons are EQ_EXPR. I.e.,
5078 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5080 WANTED_CODE is this operation code. For single bit fields, we can
5081 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5082 comparison for one-bit fields. */
5084 enum tree_code wanted_code;
5085 enum tree_code lcode, rcode;
5086 tree ll_arg, lr_arg, rl_arg, rr_arg;
5087 tree ll_inner, lr_inner, rl_inner, rr_inner;
5088 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5089 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5090 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5091 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5092 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5093 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5094 enum machine_mode lnmode, rnmode;
5095 tree ll_mask, lr_mask, rl_mask, rr_mask;
5096 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5097 tree l_const, r_const;
5098 tree lntype, rntype, result;
5099 HOST_WIDE_INT first_bit, end_bit;
5102 /* Start by getting the comparison codes. Fail if anything is volatile.
5103 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5104 it were surrounded with a NE_EXPR. */
5106 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5109 lcode = TREE_CODE (lhs);
5110 rcode = TREE_CODE (rhs);
5112 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5114 lhs = build2 (NE_EXPR, truth_type, lhs,
5115 build_int_cst (TREE_TYPE (lhs), 0));
5119 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5121 rhs = build2 (NE_EXPR, truth_type, rhs,
5122 build_int_cst (TREE_TYPE (rhs), 0));
5126 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5127 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5130 ll_arg = TREE_OPERAND (lhs, 0);
5131 lr_arg = TREE_OPERAND (lhs, 1);
5132 rl_arg = TREE_OPERAND (rhs, 0);
5133 rr_arg = TREE_OPERAND (rhs, 1);
5135 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5136 if (simple_operand_p (ll_arg)
5137 && simple_operand_p (lr_arg))
5139 if (operand_equal_p (ll_arg, rl_arg, 0)
5140 && operand_equal_p (lr_arg, rr_arg, 0))
5142 result = combine_comparisons (loc, code, lcode, rcode,
5143 truth_type, ll_arg, lr_arg);
5147 else if (operand_equal_p (ll_arg, rr_arg, 0)
5148 && operand_equal_p (lr_arg, rl_arg, 0))
5150 result = combine_comparisons (loc, code, lcode,
5151 swap_tree_comparison (rcode),
5152 truth_type, ll_arg, lr_arg);
5158 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5159 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5161 /* If the RHS can be evaluated unconditionally and its operands are
5162 simple, it wins to evaluate the RHS unconditionally on machines
5163 with expensive branches. In this case, this isn't a comparison
5164 that can be merged. */
5166 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5168 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5169 && simple_operand_p (rl_arg)
5170 && simple_operand_p (rr_arg))
5172 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5173 if (code == TRUTH_OR_EXPR
5174 && lcode == NE_EXPR && integer_zerop (lr_arg)
5175 && rcode == NE_EXPR && integer_zerop (rr_arg)
5176 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5177 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5178 return build2_loc (loc, NE_EXPR, truth_type,
5179 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5181 build_int_cst (TREE_TYPE (ll_arg), 0));
5183 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5184 if (code == TRUTH_AND_EXPR
5185 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5186 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5187 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5188 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5189 return build2_loc (loc, EQ_EXPR, truth_type,
5190 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5192 build_int_cst (TREE_TYPE (ll_arg), 0));
5195 /* See if the comparisons can be merged. Then get all the parameters for
5198 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5199 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5203 ll_inner = decode_field_reference (loc, ll_arg,
5204 &ll_bitsize, &ll_bitpos, &ll_mode,
5205 &ll_unsignedp, &volatilep, &ll_mask,
5207 lr_inner = decode_field_reference (loc, lr_arg,
5208 &lr_bitsize, &lr_bitpos, &lr_mode,
5209 &lr_unsignedp, &volatilep, &lr_mask,
5211 rl_inner = decode_field_reference (loc, rl_arg,
5212 &rl_bitsize, &rl_bitpos, &rl_mode,
5213 &rl_unsignedp, &volatilep, &rl_mask,
5215 rr_inner = decode_field_reference (loc, rr_arg,
5216 &rr_bitsize, &rr_bitpos, &rr_mode,
5217 &rr_unsignedp, &volatilep, &rr_mask,
5220 /* It must be true that the inner operation on the lhs of each
5221 comparison must be the same if we are to be able to do anything.
5222 Then see if we have constants. If not, the same must be true for
5224 if (volatilep || ll_inner == 0 || rl_inner == 0
5225 || ! operand_equal_p (ll_inner, rl_inner, 0))
5228 if (TREE_CODE (lr_arg) == INTEGER_CST
5229 && TREE_CODE (rr_arg) == INTEGER_CST)
5230 l_const = lr_arg, r_const = rr_arg;
5231 else if (lr_inner == 0 || rr_inner == 0
5232 || ! operand_equal_p (lr_inner, rr_inner, 0))
5235 l_const = r_const = 0;
5237 /* If either comparison code is not correct for our logical operation,
5238 fail. However, we can convert a one-bit comparison against zero into
5239 the opposite comparison against that bit being set in the field. */
5241 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5242 if (lcode != wanted_code)
5244 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5246 /* Make the left operand unsigned, since we are only interested
5247 in the value of one bit. Otherwise we are doing the wrong
5256 /* This is analogous to the code for l_const above. */
5257 if (rcode != wanted_code)
5259 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5268 /* See if we can find a mode that contains both fields being compared on
5269 the left. If we can't, fail. Otherwise, update all constants and masks
5270 to be relative to a field of that size. */
5271 first_bit = MIN (ll_bitpos, rl_bitpos);
5272 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5273 lnmode = get_best_mode (end_bit - first_bit, first_bit, 0, 0,
5274 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5276 if (lnmode == VOIDmode)
5279 lnbitsize = GET_MODE_BITSIZE (lnmode);
5280 lnbitpos = first_bit & ~ (lnbitsize - 1);
5281 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5282 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5284 if (BYTES_BIG_ENDIAN)
5286 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5287 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5290 ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
5291 size_int (xll_bitpos));
5292 rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
5293 size_int (xrl_bitpos));
5297 l_const = fold_convert_loc (loc, lntype, l_const);
5298 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5299 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos));
5300 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5301 fold_build1_loc (loc, BIT_NOT_EXPR,
5304 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5306 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5311 r_const = fold_convert_loc (loc, lntype, r_const);
5312 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5313 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos));
5314 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5315 fold_build1_loc (loc, BIT_NOT_EXPR,
5318 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5320 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5324 /* If the right sides are not constant, do the same for it. Also,
5325 disallow this optimization if a size or signedness mismatch occurs
5326 between the left and right sides. */
5329 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
5330 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
5331 /* Make sure the two fields on the right
5332 correspond to the left without being swapped. */
5333 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
5336 first_bit = MIN (lr_bitpos, rr_bitpos);
5337 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
5338 rnmode = get_best_mode (end_bit - first_bit, first_bit, 0, 0,
5339 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
5341 if (rnmode == VOIDmode)
5344 rnbitsize = GET_MODE_BITSIZE (rnmode);
5345 rnbitpos = first_bit & ~ (rnbitsize - 1);
5346 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
5347 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
5349 if (BYTES_BIG_ENDIAN)
5351 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
5352 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
5355 lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5357 size_int (xlr_bitpos));
5358 rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5360 size_int (xrr_bitpos));
5362 /* Make a mask that corresponds to both fields being compared.
5363 Do this for both items being compared. If the operands are the
5364 same size and the bits being compared are in the same position
5365 then we can do this by masking both and comparing the masked
5367 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5368 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask);
5369 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
5371 lhs = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5372 ll_unsignedp || rl_unsignedp);
5373 if (! all_ones_mask_p (ll_mask, lnbitsize))
5374 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
5376 rhs = make_bit_field_ref (loc, lr_inner, rntype, rnbitsize, rnbitpos,
5377 lr_unsignedp || rr_unsignedp);
5378 if (! all_ones_mask_p (lr_mask, rnbitsize))
5379 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
5381 return build2_loc (loc, wanted_code, truth_type, lhs, rhs);
5384 /* There is still another way we can do something: If both pairs of
5385 fields being compared are adjacent, we may be able to make a wider
5386 field containing them both.
5388 Note that we still must mask the lhs/rhs expressions. Furthermore,
5389 the mask must be shifted to account for the shift done by
5390 make_bit_field_ref. */
5391 if ((ll_bitsize + ll_bitpos == rl_bitpos
5392 && lr_bitsize + lr_bitpos == rr_bitpos)
5393 || (ll_bitpos == rl_bitpos + rl_bitsize
5394 && lr_bitpos == rr_bitpos + rr_bitsize))
5398 lhs = make_bit_field_ref (loc, ll_inner, lntype,
5399 ll_bitsize + rl_bitsize,
5400 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
5401 rhs = make_bit_field_ref (loc, lr_inner, rntype,
5402 lr_bitsize + rr_bitsize,
5403 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
5405 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
5406 size_int (MIN (xll_bitpos, xrl_bitpos)));
5407 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
5408 size_int (MIN (xlr_bitpos, xrr_bitpos)));
5410 /* Convert to the smaller type before masking out unwanted bits. */
5412 if (lntype != rntype)
5414 if (lnbitsize > rnbitsize)
5416 lhs = fold_convert_loc (loc, rntype, lhs);
5417 ll_mask = fold_convert_loc (loc, rntype, ll_mask);
5420 else if (lnbitsize < rnbitsize)
5422 rhs = fold_convert_loc (loc, lntype, rhs);
5423 lr_mask = fold_convert_loc (loc, lntype, lr_mask);
5428 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
5429 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
5431 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
5432 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
5434 return build2_loc (loc, wanted_code, truth_type, lhs, rhs);
5440 /* Handle the case of comparisons with constants. If there is something in
5441 common between the masks, those bits of the constants must be the same.
5442 If not, the condition is always false. Test for this to avoid generating
5443 incorrect code below. */
5444 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask);
5445 if (! integer_zerop (result)
5446 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const),
5447 const_binop (BIT_AND_EXPR, result, r_const)) != 1)
5449 if (wanted_code == NE_EXPR)
5451 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5452 return constant_boolean_node (true, truth_type);
5456 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5457 return constant_boolean_node (false, truth_type);
5461 /* Construct the expression we will return. First get the component
5462 reference we will make. Unless the mask is all ones the width of
5463 that field, perform the mask operation. Then compare with the
5465 result = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5466 ll_unsignedp || rl_unsignedp);
5468 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5469 if (! all_ones_mask_p (ll_mask, lnbitsize))
5470 result = build2_loc (loc, BIT_AND_EXPR, lntype, result, ll_mask);
5472 return build2_loc (loc, wanted_code, truth_type, result,
5473 const_binop (BIT_IOR_EXPR, l_const, r_const));
5476 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5480 optimize_minmax_comparison (location_t loc, enum tree_code code, tree type,
5484 enum tree_code op_code;
5487 int consts_equal, consts_lt;
5490 STRIP_SIGN_NOPS (arg0);
5492 op_code = TREE_CODE (arg0);
5493 minmax_const = TREE_OPERAND (arg0, 1);
5494 comp_const = fold_convert_loc (loc, TREE_TYPE (arg0), op1);
5495 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5496 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5497 inner = TREE_OPERAND (arg0, 0);
5499 /* If something does not permit us to optimize, return the original tree. */
5500 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5501 || TREE_CODE (comp_const) != INTEGER_CST
5502 || TREE_OVERFLOW (comp_const)
5503 || TREE_CODE (minmax_const) != INTEGER_CST
5504 || TREE_OVERFLOW (minmax_const))
5507 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5508 and GT_EXPR, doing the rest with recursive calls using logical
5512 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5515 = optimize_minmax_comparison (loc,
5516 invert_tree_comparison (code, false),
5519 return invert_truthvalue_loc (loc, tem);
5525 fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
5526 optimize_minmax_comparison
5527 (loc, EQ_EXPR, type, arg0, comp_const),
5528 optimize_minmax_comparison
5529 (loc, GT_EXPR, type, arg0, comp_const));
5532 if (op_code == MAX_EXPR && consts_equal)
5533 /* MAX (X, 0) == 0 -> X <= 0 */
5534 return fold_build2_loc (loc, LE_EXPR, type, inner, comp_const);
5536 else if (op_code == MAX_EXPR && consts_lt)
5537 /* MAX (X, 0) == 5 -> X == 5 */
5538 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5540 else if (op_code == MAX_EXPR)
5541 /* MAX (X, 0) == -1 -> false */
5542 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5544 else if (consts_equal)
5545 /* MIN (X, 0) == 0 -> X >= 0 */
5546 return fold_build2_loc (loc, GE_EXPR, type, inner, comp_const);
5549 /* MIN (X, 0) == 5 -> false */
5550 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5553 /* MIN (X, 0) == -1 -> X == -1 */
5554 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5557 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5558 /* MAX (X, 0) > 0 -> X > 0
5559 MAX (X, 0) > 5 -> X > 5 */
5560 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5562 else if (op_code == MAX_EXPR)
5563 /* MAX (X, 0) > -1 -> true */
5564 return omit_one_operand_loc (loc, type, integer_one_node, inner);
5566 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
5567 /* MIN (X, 0) > 0 -> false
5568 MIN (X, 0) > 5 -> false */
5569 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5572 /* MIN (X, 0) > -1 -> X > -1 */
5573 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5580 /* T is an integer expression that is being multiplied, divided, or taken a
5581 modulus (CODE says which and what kind of divide or modulus) by a
5582 constant C. See if we can eliminate that operation by folding it with
5583 other operations already in T. WIDE_TYPE, if non-null, is a type that
5584 should be used for the computation if wider than our type.
5586 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5587 (X * 2) + (Y * 4). We must, however, be assured that either the original
5588 expression would not overflow or that overflow is undefined for the type
5589 in the language in question.
5591 If we return a non-null expression, it is an equivalent form of the
5592 original computation, but need not be in the original type.
5594 We set *STRICT_OVERFLOW_P to true if the return values depends on
5595 signed overflow being undefined. Otherwise we do not change
5596 *STRICT_OVERFLOW_P. */
5599 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
5600 bool *strict_overflow_p)
5602 /* To avoid exponential search depth, refuse to allow recursion past
5603 three levels. Beyond that (1) it's highly unlikely that we'll find
5604 something interesting and (2) we've probably processed it before
5605 when we built the inner expression. */
5614 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
5621 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
5622 bool *strict_overflow_p)
5624 tree type = TREE_TYPE (t);
5625 enum tree_code tcode = TREE_CODE (t);
5626 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
5627 > GET_MODE_SIZE (TYPE_MODE (type)))
5628 ? wide_type : type);
5630 int same_p = tcode == code;
5631 tree op0 = NULL_TREE, op1 = NULL_TREE;
5632 bool sub_strict_overflow_p;
5634 /* Don't deal with constants of zero here; they confuse the code below. */
5635 if (integer_zerop (c))
5638 if (TREE_CODE_CLASS (tcode) == tcc_unary)
5639 op0 = TREE_OPERAND (t, 0);
5641 if (TREE_CODE_CLASS (tcode) == tcc_binary)
5642 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
5644 /* Note that we need not handle conditional operations here since fold
5645 already handles those cases. So just do arithmetic here. */
5649 /* For a constant, we can always simplify if we are a multiply
5650 or (for divide and modulus) if it is a multiple of our constant. */
5651 if (code == MULT_EXPR
5652 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c)))
5653 return const_binop (code, fold_convert (ctype, t),
5654 fold_convert (ctype, c));
5657 CASE_CONVERT: case NON_LVALUE_EXPR:
5658 /* If op0 is an expression ... */
5659 if ((COMPARISON_CLASS_P (op0)
5660 || UNARY_CLASS_P (op0)
5661 || BINARY_CLASS_P (op0)
5662 || VL_EXP_CLASS_P (op0)
5663 || EXPRESSION_CLASS_P (op0))
5664 /* ... and has wrapping overflow, and its type is smaller
5665 than ctype, then we cannot pass through as widening. */
5666 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
5667 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
5668 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
5669 && (TYPE_PRECISION (ctype)
5670 > TYPE_PRECISION (TREE_TYPE (op0))))
5671 /* ... or this is a truncation (t is narrower than op0),
5672 then we cannot pass through this narrowing. */
5673 || (TYPE_PRECISION (type)
5674 < TYPE_PRECISION (TREE_TYPE (op0)))
5675 /* ... or signedness changes for division or modulus,
5676 then we cannot pass through this conversion. */
5677 || (code != MULT_EXPR
5678 && (TYPE_UNSIGNED (ctype)
5679 != TYPE_UNSIGNED (TREE_TYPE (op0))))
5680 /* ... or has undefined overflow while the converted to
5681 type has not, we cannot do the operation in the inner type
5682 as that would introduce undefined overflow. */
5683 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
5684 && !TYPE_OVERFLOW_UNDEFINED (type))))
5687 /* Pass the constant down and see if we can make a simplification. If
5688 we can, replace this expression with the inner simplification for
5689 possible later conversion to our or some other type. */
5690 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
5691 && TREE_CODE (t2) == INTEGER_CST
5692 && !TREE_OVERFLOW (t2)
5693 && (0 != (t1 = extract_muldiv (op0, t2, code,
5695 ? ctype : NULL_TREE,
5696 strict_overflow_p))))
5701 /* If widening the type changes it from signed to unsigned, then we
5702 must avoid building ABS_EXPR itself as unsigned. */
5703 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
5705 tree cstype = (*signed_type_for) (ctype);
5706 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
5709 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
5710 return fold_convert (ctype, t1);
5714 /* If the constant is negative, we cannot simplify this. */
5715 if (tree_int_cst_sgn (c) == -1)
5719 /* For division and modulus, type can't be unsigned, as e.g.
5720 (-(x / 2U)) / 2U isn't equal to -((x / 2U) / 2U) for x >= 2.
5721 For signed types, even with wrapping overflow, this is fine. */
5722 if (code != MULT_EXPR && TYPE_UNSIGNED (type))
5724 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
5726 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
5729 case MIN_EXPR: case MAX_EXPR:
5730 /* If widening the type changes the signedness, then we can't perform
5731 this optimization as that changes the result. */
5732 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
5735 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
5736 sub_strict_overflow_p = false;
5737 if ((t1 = extract_muldiv (op0, c, code, wide_type,
5738 &sub_strict_overflow_p)) != 0
5739 && (t2 = extract_muldiv (op1, c, code, wide_type,
5740 &sub_strict_overflow_p)) != 0)
5742 if (tree_int_cst_sgn (c) < 0)
5743 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
5744 if (sub_strict_overflow_p)
5745 *strict_overflow_p = true;
5746 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5747 fold_convert (ctype, t2));
5751 case LSHIFT_EXPR: case RSHIFT_EXPR:
5752 /* If the second operand is constant, this is a multiplication
5753 or floor division, by a power of two, so we can treat it that
5754 way unless the multiplier or divisor overflows. Signed
5755 left-shift overflow is implementation-defined rather than
5756 undefined in C90, so do not convert signed left shift into
5758 if (TREE_CODE (op1) == INTEGER_CST
5759 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
5760 /* const_binop may not detect overflow correctly,
5761 so check for it explicitly here. */
5762 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
5763 && TREE_INT_CST_HIGH (op1) == 0
5764 && 0 != (t1 = fold_convert (ctype,
5765 const_binop (LSHIFT_EXPR,
5768 && !TREE_OVERFLOW (t1))
5769 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
5770 ? MULT_EXPR : FLOOR_DIV_EXPR,
5772 fold_convert (ctype, op0),
5774 c, code, wide_type, strict_overflow_p);
5777 case PLUS_EXPR: case MINUS_EXPR:
5778 /* See if we can eliminate the operation on both sides. If we can, we
5779 can return a new PLUS or MINUS. If we can't, the only remaining
5780 cases where we can do anything are if the second operand is a
5782 sub_strict_overflow_p = false;
5783 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
5784 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
5785 if (t1 != 0 && t2 != 0
5786 && (code == MULT_EXPR
5787 /* If not multiplication, we can only do this if both operands
5788 are divisible by c. */
5789 || (multiple_of_p (ctype, op0, c)
5790 && multiple_of_p (ctype, op1, c))))
5792 if (sub_strict_overflow_p)
5793 *strict_overflow_p = true;
5794 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5795 fold_convert (ctype, t2));
5798 /* If this was a subtraction, negate OP1 and set it to be an addition.
5799 This simplifies the logic below. */
5800 if (tcode == MINUS_EXPR)
5802 tcode = PLUS_EXPR, op1 = negate_expr (op1);
5803 /* If OP1 was not easily negatable, the constant may be OP0. */
5804 if (TREE_CODE (op0) == INTEGER_CST)
5815 if (TREE_CODE (op1) != INTEGER_CST)
5818 /* If either OP1 or C are negative, this optimization is not safe for
5819 some of the division and remainder types while for others we need
5820 to change the code. */
5821 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
5823 if (code == CEIL_DIV_EXPR)
5824 code = FLOOR_DIV_EXPR;
5825 else if (code == FLOOR_DIV_EXPR)
5826 code = CEIL_DIV_EXPR;
5827 else if (code != MULT_EXPR
5828 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
5832 /* If it's a multiply or a division/modulus operation of a multiple
5833 of our constant, do the operation and verify it doesn't overflow. */
5834 if (code == MULT_EXPR
5835 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5837 op1 = const_binop (code, fold_convert (ctype, op1),
5838 fold_convert (ctype, c));
5839 /* We allow the constant to overflow with wrapping semantics. */
5841 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
5847 /* If we have an unsigned type is not a sizetype, we cannot widen
5848 the operation since it will change the result if the original
5849 computation overflowed. */
5850 if (TYPE_UNSIGNED (ctype)
5851 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
5855 /* If we were able to eliminate our operation from the first side,
5856 apply our operation to the second side and reform the PLUS. */
5857 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
5858 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
5860 /* The last case is if we are a multiply. In that case, we can
5861 apply the distributive law to commute the multiply and addition
5862 if the multiplication of the constants doesn't overflow. */
5863 if (code == MULT_EXPR)
5864 return fold_build2 (tcode, ctype,
5865 fold_build2 (code, ctype,
5866 fold_convert (ctype, op0),
5867 fold_convert (ctype, c)),
5873 /* We have a special case here if we are doing something like
5874 (C * 8) % 4 since we know that's zero. */
5875 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
5876 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
5877 /* If the multiplication can overflow we cannot optimize this.
5878 ??? Until we can properly mark individual operations as
5879 not overflowing we need to treat sizetype special here as
5880 stor-layout relies on this opimization to make
5881 DECL_FIELD_BIT_OFFSET always a constant. */
5882 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
5883 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
5884 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
5885 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
5886 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5888 *strict_overflow_p = true;
5889 return omit_one_operand (type, integer_zero_node, op0);
5892 /* ... fall through ... */
5894 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
5895 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
5896 /* If we can extract our operation from the LHS, do so and return a
5897 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
5898 do something only if the second operand is a constant. */
5900 && (t1 = extract_muldiv (op0, c, code, wide_type,
5901 strict_overflow_p)) != 0)
5902 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5903 fold_convert (ctype, op1));
5904 else if (tcode == MULT_EXPR && code == MULT_EXPR
5905 && (t1 = extract_muldiv (op1, c, code, wide_type,
5906 strict_overflow_p)) != 0)
5907 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5908 fold_convert (ctype, t1));
5909 else if (TREE_CODE (op1) != INTEGER_CST)
5912 /* If these are the same operation types, we can associate them
5913 assuming no overflow. */
5918 mul = double_int_mul_with_sign
5920 (tree_to_double_int (op1),
5921 TYPE_PRECISION (ctype), TYPE_UNSIGNED (ctype)),
5923 (tree_to_double_int (c),
5924 TYPE_PRECISION (ctype), TYPE_UNSIGNED (ctype)),
5925 false, &overflow_p);
5926 overflow_p = (((!TYPE_UNSIGNED (ctype)
5927 || (TREE_CODE (ctype) == INTEGER_TYPE
5928 && TYPE_IS_SIZETYPE (ctype)))
5930 | TREE_OVERFLOW (c) | TREE_OVERFLOW (op1));
5931 if (!double_int_fits_to_tree_p (ctype, mul)
5932 && ((TYPE_UNSIGNED (ctype) && tcode != MULT_EXPR)
5933 || !TYPE_UNSIGNED (ctype)
5934 || (TREE_CODE (ctype) == INTEGER_TYPE
5935 && TYPE_IS_SIZETYPE (ctype))))
5938 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5939 double_int_to_tree (ctype, mul));
5942 /* If these operations "cancel" each other, we have the main
5943 optimizations of this pass, which occur when either constant is a
5944 multiple of the other, in which case we replace this with either an
5945 operation or CODE or TCODE.
5947 If we have an unsigned type that is not a sizetype, we cannot do
5948 this since it will change the result if the original computation
5950 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
5951 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
5952 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
5953 || (tcode == MULT_EXPR
5954 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
5955 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
5956 && code != MULT_EXPR)))
5958 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5960 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5961 *strict_overflow_p = true;
5962 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5963 fold_convert (ctype,
5964 const_binop (TRUNC_DIV_EXPR,
5967 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1)))
5969 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5970 *strict_overflow_p = true;
5971 return fold_build2 (code, ctype, fold_convert (ctype, op0),
5972 fold_convert (ctype,
5973 const_binop (TRUNC_DIV_EXPR,
5986 /* Return a node which has the indicated constant VALUE (either 0 or
5987 1 for scalars or {-1,-1,..} or {0,0,...} for vectors),
5988 and is of the indicated TYPE. */
5991 constant_boolean_node (bool value, tree type)
5993 if (type == integer_type_node)
5994 return value ? integer_one_node : integer_zero_node;
5995 else if (type == boolean_type_node)
5996 return value ? boolean_true_node : boolean_false_node;
5997 else if (TREE_CODE (type) == VECTOR_TYPE)
5998 return build_vector_from_val (type,
5999 build_int_cst (TREE_TYPE (type),
6002 return fold_convert (type, value ? integer_one_node : integer_zero_node);
6006 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6007 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6008 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6009 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6010 COND is the first argument to CODE; otherwise (as in the example
6011 given here), it is the second argument. TYPE is the type of the
6012 original expression. Return NULL_TREE if no simplification is
6016 fold_binary_op_with_conditional_arg (location_t loc,
6017 enum tree_code code,
6018 tree type, tree op0, tree op1,
6019 tree cond, tree arg, int cond_first_p)
6021 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6022 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6023 tree test, true_value, false_value;
6024 tree lhs = NULL_TREE;
6025 tree rhs = NULL_TREE;
6027 if (TREE_CODE (cond) == COND_EXPR)
6029 test = TREE_OPERAND (cond, 0);
6030 true_value = TREE_OPERAND (cond, 1);
6031 false_value = TREE_OPERAND (cond, 2);
6032 /* If this operand throws an expression, then it does not make
6033 sense to try to perform a logical or arithmetic operation
6035 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6037 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6042 tree testtype = TREE_TYPE (cond);
6044 true_value = constant_boolean_node (true, testtype);
6045 false_value = constant_boolean_node (false, testtype);
6048 /* This transformation is only worthwhile if we don't have to wrap ARG
6049 in a SAVE_EXPR and the operation can be simplified without recursing
6050 on at least one of the branches once its pushed inside the COND_EXPR. */
6051 if (!TREE_CONSTANT (arg)
6052 && (TREE_SIDE_EFFECTS (arg)
6053 || TREE_CODE (arg) == COND_EXPR || TREE_CODE (arg) == VEC_COND_EXPR
6054 || TREE_CONSTANT (true_value) || TREE_CONSTANT (false_value)))
6057 arg = fold_convert_loc (loc, arg_type, arg);
6060 true_value = fold_convert_loc (loc, cond_type, true_value);
6062 lhs = fold_build2_loc (loc, code, type, true_value, arg);
6064 lhs = fold_build2_loc (loc, code, type, arg, true_value);
6068 false_value = fold_convert_loc (loc, cond_type, false_value);
6070 rhs = fold_build2_loc (loc, code, type, false_value, arg);
6072 rhs = fold_build2_loc (loc, code, type, arg, false_value);
6075 /* Check that we have simplified at least one of the branches. */
6076 if (!TREE_CONSTANT (arg) && !TREE_CONSTANT (lhs) && !TREE_CONSTANT (rhs))
6079 return fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
6083 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6085 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6086 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6087 ADDEND is the same as X.
6089 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6090 and finite. The problematic cases are when X is zero, and its mode
6091 has signed zeros. In the case of rounding towards -infinity,
6092 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6093 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6096 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6098 if (!real_zerop (addend))
6101 /* Don't allow the fold with -fsignaling-nans. */
6102 if (HONOR_SNANS (TYPE_MODE (type)))
6105 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6106 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6109 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6110 if (TREE_CODE (addend) == REAL_CST
6111 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6114 /* The mode has signed zeros, and we have to honor their sign.
6115 In this situation, there is only one case we can return true for.
6116 X - 0 is the same as X unless rounding towards -infinity is
6118 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6121 /* Subroutine of fold() that checks comparisons of built-in math
6122 functions against real constants.
6124 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6125 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6126 is the type of the result and ARG0 and ARG1 are the operands of the
6127 comparison. ARG1 must be a TREE_REAL_CST.
6129 The function returns the constant folded tree if a simplification
6130 can be made, and NULL_TREE otherwise. */
6133 fold_mathfn_compare (location_t loc,
6134 enum built_in_function fcode, enum tree_code code,
6135 tree type, tree arg0, tree arg1)
6139 if (BUILTIN_SQRT_P (fcode))
6141 tree arg = CALL_EXPR_ARG (arg0, 0);
6142 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6144 c = TREE_REAL_CST (arg1);
6145 if (REAL_VALUE_NEGATIVE (c))
6147 /* sqrt(x) < y is always false, if y is negative. */
6148 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6149 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6151 /* sqrt(x) > y is always true, if y is negative and we
6152 don't care about NaNs, i.e. negative values of x. */
6153 if (code == NE_EXPR || !HONOR_NANS (mode))
6154 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6156 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6157 return fold_build2_loc (loc, GE_EXPR, type, arg,
6158 build_real (TREE_TYPE (arg), dconst0));
6160 else if (code == GT_EXPR || code == GE_EXPR)
6164 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6165 real_convert (&c2, mode, &c2);
6167 if (REAL_VALUE_ISINF (c2))
6169 /* sqrt(x) > y is x == +Inf, when y is very large. */
6170 if (HONOR_INFINITIES (mode))
6171 return fold_build2_loc (loc, EQ_EXPR, type, arg,
6172 build_real (TREE_TYPE (arg), c2));
6174 /* sqrt(x) > y is always false, when y is very large
6175 and we don't care about infinities. */
6176 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6179 /* sqrt(x) > c is the same as x > c*c. */
6180 return fold_build2_loc (loc, code, type, arg,
6181 build_real (TREE_TYPE (arg), c2));
6183 else if (code == LT_EXPR || code == LE_EXPR)
6187 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6188 real_convert (&c2, mode, &c2);
6190 if (REAL_VALUE_ISINF (c2))
6192 /* sqrt(x) < y is always true, when y is a very large
6193 value and we don't care about NaNs or Infinities. */
6194 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6195 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6197 /* sqrt(x) < y is x != +Inf when y is very large and we
6198 don't care about NaNs. */
6199 if (! HONOR_NANS (mode))
6200 return fold_build2_loc (loc, NE_EXPR, type, arg,
6201 build_real (TREE_TYPE (arg), c2));
6203 /* sqrt(x) < y is x >= 0 when y is very large and we
6204 don't care about Infinities. */
6205 if (! HONOR_INFINITIES (mode))
6206 return fold_build2_loc (loc, GE_EXPR, type, arg,
6207 build_real (TREE_TYPE (arg), dconst0));
6209 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6210 arg = save_expr (arg);
6211 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6212 fold_build2_loc (loc, GE_EXPR, type, arg,
6213 build_real (TREE_TYPE (arg),
6215 fold_build2_loc (loc, NE_EXPR, type, arg,
6216 build_real (TREE_TYPE (arg),
6220 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6221 if (! HONOR_NANS (mode))
6222 return fold_build2_loc (loc, code, type, arg,
6223 build_real (TREE_TYPE (arg), c2));
6225 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6226 arg = save_expr (arg);
6227 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6228 fold_build2_loc (loc, GE_EXPR, type, arg,
6229 build_real (TREE_TYPE (arg),
6231 fold_build2_loc (loc, code, type, arg,
6232 build_real (TREE_TYPE (arg),
6240 /* Subroutine of fold() that optimizes comparisons against Infinities,
6241 either +Inf or -Inf.
6243 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6244 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6245 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6247 The function returns the constant folded tree if a simplification
6248 can be made, and NULL_TREE otherwise. */
6251 fold_inf_compare (location_t loc, enum tree_code code, tree type,
6252 tree arg0, tree arg1)
6254 enum machine_mode mode;
6255 REAL_VALUE_TYPE max;
6259 mode = TYPE_MODE (TREE_TYPE (arg0));
6261 /* For negative infinity swap the sense of the comparison. */
6262 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6264 code = swap_tree_comparison (code);
6269 /* x > +Inf is always false, if with ignore sNANs. */
6270 if (HONOR_SNANS (mode))
6272 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6275 /* x <= +Inf is always true, if we don't case about NaNs. */
6276 if (! HONOR_NANS (mode))
6277 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6279 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6280 arg0 = save_expr (arg0);
6281 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg0);
6285 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6286 real_maxval (&max, neg, mode);
6287 return fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6288 arg0, build_real (TREE_TYPE (arg0), max));
6291 /* x < +Inf is always equal to x <= DBL_MAX. */
6292 real_maxval (&max, neg, mode);
6293 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6294 arg0, build_real (TREE_TYPE (arg0), max));
6297 /* x != +Inf is always equal to !(x > DBL_MAX). */
6298 real_maxval (&max, neg, mode);
6299 if (! HONOR_NANS (mode))
6300 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6301 arg0, build_real (TREE_TYPE (arg0), max));
6303 temp = fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6304 arg0, build_real (TREE_TYPE (arg0), max));
6305 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type, temp);
6314 /* Subroutine of fold() that optimizes comparisons of a division by
6315 a nonzero integer constant against an integer constant, i.e.
6318 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6319 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6320 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6322 The function returns the constant folded tree if a simplification
6323 can be made, and NULL_TREE otherwise. */
6326 fold_div_compare (location_t loc,
6327 enum tree_code code, tree type, tree arg0, tree arg1)
6329 tree prod, tmp, hi, lo;
6330 tree arg00 = TREE_OPERAND (arg0, 0);
6331 tree arg01 = TREE_OPERAND (arg0, 1);
6333 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6337 /* We have to do this the hard way to detect unsigned overflow.
6338 prod = int_const_binop (MULT_EXPR, arg01, arg1); */
6339 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6340 TREE_INT_CST_HIGH (arg01),
6341 TREE_INT_CST_LOW (arg1),
6342 TREE_INT_CST_HIGH (arg1),
6343 &val.low, &val.high, unsigned_p);
6344 prod = force_fit_type_double (TREE_TYPE (arg00), val, -1, overflow);
6345 neg_overflow = false;
6349 tmp = int_const_binop (MINUS_EXPR, arg01,
6350 build_int_cst (TREE_TYPE (arg01), 1));
6353 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp). */
6354 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6355 TREE_INT_CST_HIGH (prod),
6356 TREE_INT_CST_LOW (tmp),
6357 TREE_INT_CST_HIGH (tmp),
6358 &val.low, &val.high, unsigned_p);
6359 hi = force_fit_type_double (TREE_TYPE (arg00), val,
6360 -1, overflow | TREE_OVERFLOW (prod));
6362 else if (tree_int_cst_sgn (arg01) >= 0)
6364 tmp = int_const_binop (MINUS_EXPR, arg01,
6365 build_int_cst (TREE_TYPE (arg01), 1));
6366 switch (tree_int_cst_sgn (arg1))
6369 neg_overflow = true;
6370 lo = int_const_binop (MINUS_EXPR, prod, tmp);
6375 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6380 hi = int_const_binop (PLUS_EXPR, prod, tmp);
6390 /* A negative divisor reverses the relational operators. */
6391 code = swap_tree_comparison (code);
6393 tmp = int_const_binop (PLUS_EXPR, arg01,
6394 build_int_cst (TREE_TYPE (arg01), 1));
6395 switch (tree_int_cst_sgn (arg1))
6398 hi = int_const_binop (MINUS_EXPR, prod, tmp);
6403 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6408 neg_overflow = true;
6409 lo = int_const_binop (PLUS_EXPR, prod, tmp);
6421 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6422 return omit_one_operand_loc (loc, type, integer_zero_node, arg00);
6423 if (TREE_OVERFLOW (hi))
6424 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6425 if (TREE_OVERFLOW (lo))
6426 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6427 return build_range_check (loc, type, arg00, 1, lo, hi);
6430 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6431 return omit_one_operand_loc (loc, type, integer_one_node, arg00);
6432 if (TREE_OVERFLOW (hi))
6433 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6434 if (TREE_OVERFLOW (lo))
6435 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6436 return build_range_check (loc, type, arg00, 0, lo, hi);
6439 if (TREE_OVERFLOW (lo))
6441 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6442 return omit_one_operand_loc (loc, type, tmp, arg00);
6444 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6447 if (TREE_OVERFLOW (hi))
6449 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6450 return omit_one_operand_loc (loc, type, tmp, arg00);
6452 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6455 if (TREE_OVERFLOW (hi))
6457 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6458 return omit_one_operand_loc (loc, type, tmp, arg00);
6460 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6463 if (TREE_OVERFLOW (lo))
6465 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6466 return omit_one_operand_loc (loc, type, tmp, arg00);
6468 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6478 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6479 equality/inequality test, then return a simplified form of the test
6480 using a sign testing. Otherwise return NULL. TYPE is the desired
6484 fold_single_bit_test_into_sign_test (location_t loc,
6485 enum tree_code code, tree arg0, tree arg1,
6488 /* If this is testing a single bit, we can optimize the test. */
6489 if ((code == NE_EXPR || code == EQ_EXPR)
6490 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6491 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6493 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6494 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6495 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6497 if (arg00 != NULL_TREE
6498 /* This is only a win if casting to a signed type is cheap,
6499 i.e. when arg00's type is not a partial mode. */
6500 && TYPE_PRECISION (TREE_TYPE (arg00))
6501 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6503 tree stype = signed_type_for (TREE_TYPE (arg00));
6504 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6506 fold_convert_loc (loc, stype, arg00),
6507 build_int_cst (stype, 0));
6514 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6515 equality/inequality test, then return a simplified form of
6516 the test using shifts and logical operations. Otherwise return
6517 NULL. TYPE is the desired result type. */
6520 fold_single_bit_test (location_t loc, enum tree_code code,
6521 tree arg0, tree arg1, tree result_type)
6523 /* If this is testing a single bit, we can optimize the test. */
6524 if ((code == NE_EXPR || code == EQ_EXPR)
6525 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6526 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6528 tree inner = TREE_OPERAND (arg0, 0);
6529 tree type = TREE_TYPE (arg0);
6530 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6531 enum machine_mode operand_mode = TYPE_MODE (type);
6533 tree signed_type, unsigned_type, intermediate_type;
6536 /* First, see if we can fold the single bit test into a sign-bit
6538 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1,
6543 /* Otherwise we have (A & C) != 0 where C is a single bit,
6544 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6545 Similarly for (A & C) == 0. */
6547 /* If INNER is a right shift of a constant and it plus BITNUM does
6548 not overflow, adjust BITNUM and INNER. */
6549 if (TREE_CODE (inner) == RSHIFT_EXPR
6550 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6551 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6552 && bitnum < TYPE_PRECISION (type)
6553 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6554 bitnum - TYPE_PRECISION (type)))
6556 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6557 inner = TREE_OPERAND (inner, 0);
6560 /* If we are going to be able to omit the AND below, we must do our
6561 operations as unsigned. If we must use the AND, we have a choice.
6562 Normally unsigned is faster, but for some machines signed is. */
6563 #ifdef LOAD_EXTEND_OP
6564 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6565 && !flag_syntax_only) ? 0 : 1;
6570 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6571 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6572 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6573 inner = fold_convert_loc (loc, intermediate_type, inner);
6576 inner = build2 (RSHIFT_EXPR, intermediate_type,
6577 inner, size_int (bitnum));
6579 one = build_int_cst (intermediate_type, 1);
6581 if (code == EQ_EXPR)
6582 inner = fold_build2_loc (loc, BIT_XOR_EXPR, intermediate_type, inner, one);
6584 /* Put the AND last so it can combine with more things. */
6585 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6587 /* Make sure to return the proper type. */
6588 inner = fold_convert_loc (loc, result_type, inner);
6595 /* Check whether we are allowed to reorder operands arg0 and arg1,
6596 such that the evaluation of arg1 occurs before arg0. */
6599 reorder_operands_p (const_tree arg0, const_tree arg1)
6601 if (! flag_evaluation_order)
6603 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
6605 return ! TREE_SIDE_EFFECTS (arg0)
6606 && ! TREE_SIDE_EFFECTS (arg1);
6609 /* Test whether it is preferable two swap two operands, ARG0 and
6610 ARG1, for example because ARG0 is an integer constant and ARG1
6611 isn't. If REORDER is true, only recommend swapping if we can
6612 evaluate the operands in reverse order. */
6615 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
6617 STRIP_SIGN_NOPS (arg0);
6618 STRIP_SIGN_NOPS (arg1);
6620 if (TREE_CODE (arg1) == INTEGER_CST)
6622 if (TREE_CODE (arg0) == INTEGER_CST)
6625 if (TREE_CODE (arg1) == REAL_CST)
6627 if (TREE_CODE (arg0) == REAL_CST)
6630 if (TREE_CODE (arg1) == FIXED_CST)
6632 if (TREE_CODE (arg0) == FIXED_CST)
6635 if (TREE_CODE (arg1) == COMPLEX_CST)
6637 if (TREE_CODE (arg0) == COMPLEX_CST)
6640 if (TREE_CONSTANT (arg1))
6642 if (TREE_CONSTANT (arg0))
6645 if (optimize_function_for_size_p (cfun))
6648 if (reorder && flag_evaluation_order
6649 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
6652 /* It is preferable to swap two SSA_NAME to ensure a canonical form
6653 for commutative and comparison operators. Ensuring a canonical
6654 form allows the optimizers to find additional redundancies without
6655 having to explicitly check for both orderings. */
6656 if (TREE_CODE (arg0) == SSA_NAME
6657 && TREE_CODE (arg1) == SSA_NAME
6658 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
6661 /* Put SSA_NAMEs last. */
6662 if (TREE_CODE (arg1) == SSA_NAME)
6664 if (TREE_CODE (arg0) == SSA_NAME)
6667 /* Put variables last. */
6676 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
6677 ARG0 is extended to a wider type. */
6680 fold_widened_comparison (location_t loc, enum tree_code code,
6681 tree type, tree arg0, tree arg1)
6683 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
6685 tree shorter_type, outer_type;
6689 if (arg0_unw == arg0)
6691 shorter_type = TREE_TYPE (arg0_unw);
6693 #ifdef HAVE_canonicalize_funcptr_for_compare
6694 /* Disable this optimization if we're casting a function pointer
6695 type on targets that require function pointer canonicalization. */
6696 if (HAVE_canonicalize_funcptr_for_compare
6697 && TREE_CODE (shorter_type) == POINTER_TYPE
6698 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
6702 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
6705 arg1_unw = get_unwidened (arg1, NULL_TREE);
6707 /* If possible, express the comparison in the shorter mode. */
6708 if ((code == EQ_EXPR || code == NE_EXPR
6709 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
6710 && (TREE_TYPE (arg1_unw) == shorter_type
6711 || ((TYPE_PRECISION (shorter_type)
6712 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
6713 && (TYPE_UNSIGNED (shorter_type)
6714 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
6715 || (TREE_CODE (arg1_unw) == INTEGER_CST
6716 && (TREE_CODE (shorter_type) == INTEGER_TYPE
6717 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
6718 && int_fits_type_p (arg1_unw, shorter_type))))
6719 return fold_build2_loc (loc, code, type, arg0_unw,
6720 fold_convert_loc (loc, shorter_type, arg1_unw));
6722 if (TREE_CODE (arg1_unw) != INTEGER_CST
6723 || TREE_CODE (shorter_type) != INTEGER_TYPE
6724 || !int_fits_type_p (arg1_unw, shorter_type))
6727 /* If we are comparing with the integer that does not fit into the range
6728 of the shorter type, the result is known. */
6729 outer_type = TREE_TYPE (arg1_unw);
6730 min = lower_bound_in_type (outer_type, shorter_type);
6731 max = upper_bound_in_type (outer_type, shorter_type);
6733 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6735 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6742 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6747 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6753 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6755 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6760 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6762 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6771 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
6772 ARG0 just the signedness is changed. */
6775 fold_sign_changed_comparison (location_t loc, enum tree_code code, tree type,
6776 tree arg0, tree arg1)
6779 tree inner_type, outer_type;
6781 if (!CONVERT_EXPR_P (arg0))
6784 outer_type = TREE_TYPE (arg0);
6785 arg0_inner = TREE_OPERAND (arg0, 0);
6786 inner_type = TREE_TYPE (arg0_inner);
6788 #ifdef HAVE_canonicalize_funcptr_for_compare
6789 /* Disable this optimization if we're casting a function pointer
6790 type on targets that require function pointer canonicalization. */
6791 if (HAVE_canonicalize_funcptr_for_compare
6792 && TREE_CODE (inner_type) == POINTER_TYPE
6793 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
6797 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
6800 if (TREE_CODE (arg1) != INTEGER_CST
6801 && !(CONVERT_EXPR_P (arg1)
6802 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
6805 if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
6810 if (POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
6813 if (TREE_CODE (arg1) == INTEGER_CST)
6814 arg1 = force_fit_type_double (inner_type, tree_to_double_int (arg1),
6815 0, TREE_OVERFLOW (arg1));
6817 arg1 = fold_convert_loc (loc, inner_type, arg1);
6819 return fold_build2_loc (loc, code, type, arg0_inner, arg1);
6822 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
6823 step of the array. Reconstructs s and delta in the case of s *
6824 delta being an integer constant (and thus already folded). ADDR is
6825 the address. MULT is the multiplicative expression. If the
6826 function succeeds, the new address expression is returned.
6827 Otherwise NULL_TREE is returned. LOC is the location of the
6828 resulting expression. */
6831 try_move_mult_to_index (location_t loc, tree addr, tree op1)
6833 tree s, delta, step;
6834 tree ref = TREE_OPERAND (addr, 0), pref;
6839 /* Strip the nops that might be added when converting op1 to sizetype. */
6842 /* Canonicalize op1 into a possibly non-constant delta
6843 and an INTEGER_CST s. */
6844 if (TREE_CODE (op1) == MULT_EXPR)
6846 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
6851 if (TREE_CODE (arg0) == INTEGER_CST)
6856 else if (TREE_CODE (arg1) == INTEGER_CST)
6864 else if (TREE_CODE (op1) == INTEGER_CST)
6871 /* Simulate we are delta * 1. */
6873 s = integer_one_node;
6876 /* Handle &x.array the same as we would handle &x.array[0]. */
6877 if (TREE_CODE (ref) == COMPONENT_REF
6878 && TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE)
6882 /* Remember if this was a multi-dimensional array. */
6883 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
6886 domain = TYPE_DOMAIN (TREE_TYPE (ref));
6889 itype = TREE_TYPE (domain);
6891 step = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (ref)));
6892 if (TREE_CODE (step) != INTEGER_CST)
6897 if (! tree_int_cst_equal (step, s))
6902 /* Try if delta is a multiple of step. */
6903 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
6909 /* Only fold here if we can verify we do not overflow one
6910 dimension of a multi-dimensional array. */
6915 if (!TYPE_MIN_VALUE (domain)
6916 || !TYPE_MAX_VALUE (domain)
6917 || TREE_CODE (TYPE_MAX_VALUE (domain)) != INTEGER_CST)
6920 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
6921 fold_convert_loc (loc, itype,
6922 TYPE_MIN_VALUE (domain)),
6923 fold_convert_loc (loc, itype, delta));
6924 if (TREE_CODE (tmp) != INTEGER_CST
6925 || tree_int_cst_lt (TYPE_MAX_VALUE (domain), tmp))
6929 /* We found a suitable component reference. */
6931 pref = TREE_OPERAND (addr, 0);
6932 ret = copy_node (pref);
6933 SET_EXPR_LOCATION (ret, loc);
6935 ret = build4_loc (loc, ARRAY_REF, TREE_TYPE (TREE_TYPE (ref)), ret,
6937 (loc, PLUS_EXPR, itype,
6938 fold_convert_loc (loc, itype,
6940 (TYPE_DOMAIN (TREE_TYPE (ref)))),
6941 fold_convert_loc (loc, itype, delta)),
6942 NULL_TREE, NULL_TREE);
6943 return build_fold_addr_expr_loc (loc, ret);
6948 for (;; ref = TREE_OPERAND (ref, 0))
6950 if (TREE_CODE (ref) == ARRAY_REF)
6954 /* Remember if this was a multi-dimensional array. */
6955 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
6958 domain = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
6961 itype = TREE_TYPE (domain);
6963 step = array_ref_element_size (ref);
6964 if (TREE_CODE (step) != INTEGER_CST)
6969 if (! tree_int_cst_equal (step, s))
6974 /* Try if delta is a multiple of step. */
6975 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
6981 /* Only fold here if we can verify we do not overflow one
6982 dimension of a multi-dimensional array. */
6987 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
6988 || !TYPE_MAX_VALUE (domain)
6989 || TREE_CODE (TYPE_MAX_VALUE (domain)) != INTEGER_CST)
6992 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
6993 fold_convert_loc (loc, itype,
6994 TREE_OPERAND (ref, 1)),
6995 fold_convert_loc (loc, itype, delta));
6997 || TREE_CODE (tmp) != INTEGER_CST
6998 || tree_int_cst_lt (TYPE_MAX_VALUE (domain), tmp))
7007 if (!handled_component_p (ref))
7011 /* We found the suitable array reference. So copy everything up to it,
7012 and replace the index. */
7014 pref = TREE_OPERAND (addr, 0);
7015 ret = copy_node (pref);
7016 SET_EXPR_LOCATION (ret, loc);
7021 pref = TREE_OPERAND (pref, 0);
7022 TREE_OPERAND (pos, 0) = copy_node (pref);
7023 pos = TREE_OPERAND (pos, 0);
7026 TREE_OPERAND (pos, 1)
7027 = fold_build2_loc (loc, PLUS_EXPR, itype,
7028 fold_convert_loc (loc, itype, TREE_OPERAND (pos, 1)),
7029 fold_convert_loc (loc, itype, delta));
7030 return fold_build1_loc (loc, ADDR_EXPR, TREE_TYPE (addr), ret);
7034 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7035 means A >= Y && A != MAX, but in this case we know that
7036 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7039 fold_to_nonsharp_ineq_using_bound (location_t loc, tree ineq, tree bound)
7041 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
7043 if (TREE_CODE (bound) == LT_EXPR)
7044 a = TREE_OPERAND (bound, 0);
7045 else if (TREE_CODE (bound) == GT_EXPR)
7046 a = TREE_OPERAND (bound, 1);
7050 typea = TREE_TYPE (a);
7051 if (!INTEGRAL_TYPE_P (typea)
7052 && !POINTER_TYPE_P (typea))
7055 if (TREE_CODE (ineq) == LT_EXPR)
7057 a1 = TREE_OPERAND (ineq, 1);
7058 y = TREE_OPERAND (ineq, 0);
7060 else if (TREE_CODE (ineq) == GT_EXPR)
7062 a1 = TREE_OPERAND (ineq, 0);
7063 y = TREE_OPERAND (ineq, 1);
7068 if (TREE_TYPE (a1) != typea)
7071 if (POINTER_TYPE_P (typea))
7073 /* Convert the pointer types into integer before taking the difference. */
7074 tree ta = fold_convert_loc (loc, ssizetype, a);
7075 tree ta1 = fold_convert_loc (loc, ssizetype, a1);
7076 diff = fold_binary_loc (loc, MINUS_EXPR, ssizetype, ta1, ta);
7079 diff = fold_binary_loc (loc, MINUS_EXPR, typea, a1, a);
7081 if (!diff || !integer_onep (diff))
7084 return fold_build2_loc (loc, GE_EXPR, type, a, y);
7087 /* Fold a sum or difference of at least one multiplication.
7088 Returns the folded tree or NULL if no simplification could be made. */
7091 fold_plusminus_mult_expr (location_t loc, enum tree_code code, tree type,
7092 tree arg0, tree arg1)
7094 tree arg00, arg01, arg10, arg11;
7095 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7097 /* (A * C) +- (B * C) -> (A+-B) * C.
7098 (A * C) +- A -> A * (C+-1).
7099 We are most concerned about the case where C is a constant,
7100 but other combinations show up during loop reduction. Since
7101 it is not difficult, try all four possibilities. */
7103 if (TREE_CODE (arg0) == MULT_EXPR)
7105 arg00 = TREE_OPERAND (arg0, 0);
7106 arg01 = TREE_OPERAND (arg0, 1);
7108 else if (TREE_CODE (arg0) == INTEGER_CST)
7110 arg00 = build_one_cst (type);
7115 /* We cannot generate constant 1 for fract. */
7116 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7119 arg01 = build_one_cst (type);
7121 if (TREE_CODE (arg1) == MULT_EXPR)
7123 arg10 = TREE_OPERAND (arg1, 0);
7124 arg11 = TREE_OPERAND (arg1, 1);
7126 else if (TREE_CODE (arg1) == INTEGER_CST)
7128 arg10 = build_one_cst (type);
7129 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7130 the purpose of this canonicalization. */
7131 if (TREE_INT_CST_HIGH (arg1) == -1
7132 && negate_expr_p (arg1)
7133 && code == PLUS_EXPR)
7135 arg11 = negate_expr (arg1);
7143 /* We cannot generate constant 1 for fract. */
7144 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7147 arg11 = build_one_cst (type);
7151 if (operand_equal_p (arg01, arg11, 0))
7152 same = arg01, alt0 = arg00, alt1 = arg10;
7153 else if (operand_equal_p (arg00, arg10, 0))
7154 same = arg00, alt0 = arg01, alt1 = arg11;
7155 else if (operand_equal_p (arg00, arg11, 0))
7156 same = arg00, alt0 = arg01, alt1 = arg10;
7157 else if (operand_equal_p (arg01, arg10, 0))
7158 same = arg01, alt0 = arg00, alt1 = arg11;
7160 /* No identical multiplicands; see if we can find a common
7161 power-of-two factor in non-power-of-two multiplies. This
7162 can help in multi-dimensional array access. */
7163 else if (host_integerp (arg01, 0)
7164 && host_integerp (arg11, 0))
7166 HOST_WIDE_INT int01, int11, tmp;
7169 int01 = TREE_INT_CST_LOW (arg01);
7170 int11 = TREE_INT_CST_LOW (arg11);
7172 /* Move min of absolute values to int11. */
7173 if (absu_hwi (int01) < absu_hwi (int11))
7175 tmp = int01, int01 = int11, int11 = tmp;
7176 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7183 if (exact_log2 (absu_hwi (int11)) > 0 && int01 % int11 == 0
7184 /* The remainder should not be a constant, otherwise we
7185 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7186 increased the number of multiplications necessary. */
7187 && TREE_CODE (arg10) != INTEGER_CST)
7189 alt0 = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (arg00), arg00,
7190 build_int_cst (TREE_TYPE (arg00),
7195 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7200 return fold_build2_loc (loc, MULT_EXPR, type,
7201 fold_build2_loc (loc, code, type,
7202 fold_convert_loc (loc, type, alt0),
7203 fold_convert_loc (loc, type, alt1)),
7204 fold_convert_loc (loc, type, same));
7209 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7210 specified by EXPR into the buffer PTR of length LEN bytes.
7211 Return the number of bytes placed in the buffer, or zero
7215 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7217 tree type = TREE_TYPE (expr);
7218 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7219 int byte, offset, word, words;
7220 unsigned char value;
7222 if (total_bytes > len)
7224 words = total_bytes / UNITS_PER_WORD;
7226 for (byte = 0; byte < total_bytes; byte++)
7228 int bitpos = byte * BITS_PER_UNIT;
7229 if (bitpos < HOST_BITS_PER_WIDE_INT)
7230 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7232 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7233 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7235 if (total_bytes > UNITS_PER_WORD)
7237 word = byte / UNITS_PER_WORD;
7238 if (WORDS_BIG_ENDIAN)
7239 word = (words - 1) - word;
7240 offset = word * UNITS_PER_WORD;
7241 if (BYTES_BIG_ENDIAN)
7242 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7244 offset += byte % UNITS_PER_WORD;
7247 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7248 ptr[offset] = value;
7254 /* Subroutine of native_encode_expr. Encode the REAL_CST
7255 specified by EXPR into the buffer PTR of length LEN bytes.
7256 Return the number of bytes placed in the buffer, or zero
7260 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7262 tree type = TREE_TYPE (expr);
7263 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7264 int byte, offset, word, words, bitpos;
7265 unsigned char value;
7267 /* There are always 32 bits in each long, no matter the size of
7268 the hosts long. We handle floating point representations with
7272 if (total_bytes > len)
7274 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7276 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7278 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7279 bitpos += BITS_PER_UNIT)
7281 byte = (bitpos / BITS_PER_UNIT) & 3;
7282 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7284 if (UNITS_PER_WORD < 4)
7286 word = byte / UNITS_PER_WORD;
7287 if (WORDS_BIG_ENDIAN)
7288 word = (words - 1) - word;
7289 offset = word * UNITS_PER_WORD;
7290 if (BYTES_BIG_ENDIAN)
7291 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7293 offset += byte % UNITS_PER_WORD;
7296 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7297 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7302 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7303 specified by EXPR into the buffer PTR of length LEN bytes.
7304 Return the number of bytes placed in the buffer, or zero
7308 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7313 part = TREE_REALPART (expr);
7314 rsize = native_encode_expr (part, ptr, len);
7317 part = TREE_IMAGPART (expr);
7318 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7321 return rsize + isize;
7325 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7326 specified by EXPR into the buffer PTR of length LEN bytes.
7327 Return the number of bytes placed in the buffer, or zero
7331 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7333 int i, size, offset, count;
7334 tree itype, elem, elements;
7337 elements = TREE_VECTOR_CST_ELTS (expr);
7338 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7339 itype = TREE_TYPE (TREE_TYPE (expr));
7340 size = GET_MODE_SIZE (TYPE_MODE (itype));
7341 for (i = 0; i < count; i++)
7345 elem = TREE_VALUE (elements);
7346 elements = TREE_CHAIN (elements);
7353 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7358 if (offset + size > len)
7360 memset (ptr+offset, 0, size);
7368 /* Subroutine of native_encode_expr. Encode the STRING_CST
7369 specified by EXPR into the buffer PTR of length LEN bytes.
7370 Return the number of bytes placed in the buffer, or zero
7374 native_encode_string (const_tree expr, unsigned char *ptr, int len)
7376 tree type = TREE_TYPE (expr);
7377 HOST_WIDE_INT total_bytes;
7379 if (TREE_CODE (type) != ARRAY_TYPE
7380 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
7381 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
7382 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
7384 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
7385 if (total_bytes > len)
7387 if (TREE_STRING_LENGTH (expr) < total_bytes)
7389 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
7390 memset (ptr + TREE_STRING_LENGTH (expr), 0,
7391 total_bytes - TREE_STRING_LENGTH (expr));
7394 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
7399 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7400 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7401 buffer PTR of length LEN bytes. Return the number of bytes
7402 placed in the buffer, or zero upon failure. */
7405 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7407 switch (TREE_CODE (expr))
7410 return native_encode_int (expr, ptr, len);
7413 return native_encode_real (expr, ptr, len);
7416 return native_encode_complex (expr, ptr, len);
7419 return native_encode_vector (expr, ptr, len);
7422 return native_encode_string (expr, ptr, len);
7430 /* Subroutine of native_interpret_expr. Interpret the contents of
7431 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7432 If the buffer cannot be interpreted, return NULL_TREE. */
7435 native_interpret_int (tree type, const unsigned char *ptr, int len)
7437 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7438 int byte, offset, word, words;
7439 unsigned char value;
7442 if (total_bytes > len)
7444 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7447 result = double_int_zero;
7448 words = total_bytes / UNITS_PER_WORD;
7450 for (byte = 0; byte < total_bytes; byte++)
7452 int bitpos = byte * BITS_PER_UNIT;
7453 if (total_bytes > UNITS_PER_WORD)
7455 word = byte / UNITS_PER_WORD;
7456 if (WORDS_BIG_ENDIAN)
7457 word = (words - 1) - word;
7458 offset = word * UNITS_PER_WORD;
7459 if (BYTES_BIG_ENDIAN)
7460 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7462 offset += byte % UNITS_PER_WORD;
7465 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7466 value = ptr[offset];
7468 if (bitpos < HOST_BITS_PER_WIDE_INT)
7469 result.low |= (unsigned HOST_WIDE_INT) value << bitpos;
7471 result.high |= (unsigned HOST_WIDE_INT) value
7472 << (bitpos - HOST_BITS_PER_WIDE_INT);
7475 return double_int_to_tree (type, result);
7479 /* Subroutine of native_interpret_expr. Interpret the contents of
7480 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7481 If the buffer cannot be interpreted, return NULL_TREE. */
7484 native_interpret_real (tree type, const unsigned char *ptr, int len)
7486 enum machine_mode mode = TYPE_MODE (type);
7487 int total_bytes = GET_MODE_SIZE (mode);
7488 int byte, offset, word, words, bitpos;
7489 unsigned char value;
7490 /* There are always 32 bits in each long, no matter the size of
7491 the hosts long. We handle floating point representations with
7496 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7497 if (total_bytes > len || total_bytes > 24)
7499 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7501 memset (tmp, 0, sizeof (tmp));
7502 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7503 bitpos += BITS_PER_UNIT)
7505 byte = (bitpos / BITS_PER_UNIT) & 3;
7506 if (UNITS_PER_WORD < 4)
7508 word = byte / UNITS_PER_WORD;
7509 if (WORDS_BIG_ENDIAN)
7510 word = (words - 1) - word;
7511 offset = word * UNITS_PER_WORD;
7512 if (BYTES_BIG_ENDIAN)
7513 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7515 offset += byte % UNITS_PER_WORD;
7518 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7519 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7521 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7524 real_from_target (&r, tmp, mode);
7525 return build_real (type, r);
7529 /* Subroutine of native_interpret_expr. Interpret the contents of
7530 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7531 If the buffer cannot be interpreted, return NULL_TREE. */
7534 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7536 tree etype, rpart, ipart;
7539 etype = TREE_TYPE (type);
7540 size = GET_MODE_SIZE (TYPE_MODE (etype));
7543 rpart = native_interpret_expr (etype, ptr, size);
7546 ipart = native_interpret_expr (etype, ptr+size, size);
7549 return build_complex (type, rpart, ipart);
7553 /* Subroutine of native_interpret_expr. Interpret the contents of
7554 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7555 If the buffer cannot be interpreted, return NULL_TREE. */
7558 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7560 tree etype, elem, elements;
7563 etype = TREE_TYPE (type);
7564 size = GET_MODE_SIZE (TYPE_MODE (etype));
7565 count = TYPE_VECTOR_SUBPARTS (type);
7566 if (size * count > len)
7569 elements = NULL_TREE;
7570 for (i = count - 1; i >= 0; i--)
7572 elem = native_interpret_expr (etype, ptr+(i*size), size);
7575 elements = tree_cons (NULL_TREE, elem, elements);
7577 return build_vector (type, elements);
7581 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7582 the buffer PTR of length LEN as a constant of type TYPE. For
7583 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7584 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7585 return NULL_TREE. */
7588 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7590 switch (TREE_CODE (type))
7595 return native_interpret_int (type, ptr, len);
7598 return native_interpret_real (type, ptr, len);
7601 return native_interpret_complex (type, ptr, len);
7604 return native_interpret_vector (type, ptr, len);
7612 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7613 TYPE at compile-time. If we're unable to perform the conversion
7614 return NULL_TREE. */
7617 fold_view_convert_expr (tree type, tree expr)
7619 /* We support up to 512-bit values (for V8DFmode). */
7620 unsigned char buffer[64];
7623 /* Check that the host and target are sane. */
7624 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7627 len = native_encode_expr (expr, buffer, sizeof (buffer));
7631 return native_interpret_expr (type, buffer, len);
7634 /* Build an expression for the address of T. Folds away INDIRECT_REF
7635 to avoid confusing the gimplify process. */
7638 build_fold_addr_expr_with_type_loc (location_t loc, tree t, tree ptrtype)
7640 /* The size of the object is not relevant when talking about its address. */
7641 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7642 t = TREE_OPERAND (t, 0);
7644 if (TREE_CODE (t) == INDIRECT_REF)
7646 t = TREE_OPERAND (t, 0);
7648 if (TREE_TYPE (t) != ptrtype)
7649 t = build1_loc (loc, NOP_EXPR, ptrtype, t);
7651 else if (TREE_CODE (t) == MEM_REF
7652 && integer_zerop (TREE_OPERAND (t, 1)))
7653 return TREE_OPERAND (t, 0);
7654 else if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
7656 t = build_fold_addr_expr_loc (loc, TREE_OPERAND (t, 0));
7658 if (TREE_TYPE (t) != ptrtype)
7659 t = fold_convert_loc (loc, ptrtype, t);
7662 t = build1_loc (loc, ADDR_EXPR, ptrtype, t);
7667 /* Build an expression for the address of T. */
7670 build_fold_addr_expr_loc (location_t loc, tree t)
7672 tree ptrtype = build_pointer_type (TREE_TYPE (t));
7674 return build_fold_addr_expr_with_type_loc (loc, t, ptrtype);
7677 static bool vec_cst_ctor_to_array (tree, tree *);
7679 /* Fold a unary expression of code CODE and type TYPE with operand
7680 OP0. Return the folded expression if folding is successful.
7681 Otherwise, return NULL_TREE. */
7684 fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
7688 enum tree_code_class kind = TREE_CODE_CLASS (code);
7690 gcc_assert (IS_EXPR_CODE_CLASS (kind)
7691 && TREE_CODE_LENGTH (code) == 1);
7696 if (CONVERT_EXPR_CODE_P (code)
7697 || code == FLOAT_EXPR || code == ABS_EXPR || code == NEGATE_EXPR)
7699 /* Don't use STRIP_NOPS, because signedness of argument type
7701 STRIP_SIGN_NOPS (arg0);
7705 /* Strip any conversions that don't change the mode. This
7706 is safe for every expression, except for a comparison
7707 expression because its signedness is derived from its
7710 Note that this is done as an internal manipulation within
7711 the constant folder, in order to find the simplest
7712 representation of the arguments so that their form can be
7713 studied. In any cases, the appropriate type conversions
7714 should be put back in the tree that will get out of the
7720 if (TREE_CODE_CLASS (code) == tcc_unary)
7722 if (TREE_CODE (arg0) == COMPOUND_EXPR)
7723 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
7724 fold_build1_loc (loc, code, type,
7725 fold_convert_loc (loc, TREE_TYPE (op0),
7726 TREE_OPERAND (arg0, 1))));
7727 else if (TREE_CODE (arg0) == COND_EXPR)
7729 tree arg01 = TREE_OPERAND (arg0, 1);
7730 tree arg02 = TREE_OPERAND (arg0, 2);
7731 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
7732 arg01 = fold_build1_loc (loc, code, type,
7733 fold_convert_loc (loc,
7734 TREE_TYPE (op0), arg01));
7735 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
7736 arg02 = fold_build1_loc (loc, code, type,
7737 fold_convert_loc (loc,
7738 TREE_TYPE (op0), arg02));
7739 tem = fold_build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg0, 0),
7742 /* If this was a conversion, and all we did was to move into
7743 inside the COND_EXPR, bring it back out. But leave it if
7744 it is a conversion from integer to integer and the
7745 result precision is no wider than a word since such a
7746 conversion is cheap and may be optimized away by combine,
7747 while it couldn't if it were outside the COND_EXPR. Then return
7748 so we don't get into an infinite recursion loop taking the
7749 conversion out and then back in. */
7751 if ((CONVERT_EXPR_CODE_P (code)
7752 || code == NON_LVALUE_EXPR)
7753 && TREE_CODE (tem) == COND_EXPR
7754 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
7755 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
7756 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
7757 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
7758 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
7759 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
7760 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7762 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
7763 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
7764 || flag_syntax_only))
7765 tem = build1_loc (loc, code, type,
7767 TREE_TYPE (TREE_OPERAND
7768 (TREE_OPERAND (tem, 1), 0)),
7769 TREE_OPERAND (tem, 0),
7770 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
7771 TREE_OPERAND (TREE_OPERAND (tem, 2),
7780 /* Re-association barriers around constants and other re-association
7781 barriers can be removed. */
7782 if (CONSTANT_CLASS_P (op0)
7783 || TREE_CODE (op0) == PAREN_EXPR)
7784 return fold_convert_loc (loc, type, op0);
7789 case FIX_TRUNC_EXPR:
7790 if (TREE_TYPE (op0) == type)
7793 if (COMPARISON_CLASS_P (op0))
7795 /* If we have (type) (a CMP b) and type is an integral type, return
7796 new expression involving the new type. Canonicalize
7797 (type) (a CMP b) to (a CMP b) ? (type) true : (type) false for
7799 Do not fold the result as that would not simplify further, also
7800 folding again results in recursions. */
7801 if (TREE_CODE (type) == BOOLEAN_TYPE)
7802 return build2_loc (loc, TREE_CODE (op0), type,
7803 TREE_OPERAND (op0, 0),
7804 TREE_OPERAND (op0, 1));
7805 else if (!INTEGRAL_TYPE_P (type))
7806 return build3_loc (loc, COND_EXPR, type, op0,
7807 constant_boolean_node (true, type),
7808 constant_boolean_node (false, type));
7811 /* Handle cases of two conversions in a row. */
7812 if (CONVERT_EXPR_P (op0))
7814 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
7815 tree inter_type = TREE_TYPE (op0);
7816 int inside_int = INTEGRAL_TYPE_P (inside_type);
7817 int inside_ptr = POINTER_TYPE_P (inside_type);
7818 int inside_float = FLOAT_TYPE_P (inside_type);
7819 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
7820 unsigned int inside_prec = TYPE_PRECISION (inside_type);
7821 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
7822 int inter_int = INTEGRAL_TYPE_P (inter_type);
7823 int inter_ptr = POINTER_TYPE_P (inter_type);
7824 int inter_float = FLOAT_TYPE_P (inter_type);
7825 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
7826 unsigned int inter_prec = TYPE_PRECISION (inter_type);
7827 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
7828 int final_int = INTEGRAL_TYPE_P (type);
7829 int final_ptr = POINTER_TYPE_P (type);
7830 int final_float = FLOAT_TYPE_P (type);
7831 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
7832 unsigned int final_prec = TYPE_PRECISION (type);
7833 int final_unsignedp = TYPE_UNSIGNED (type);
7835 /* In addition to the cases of two conversions in a row
7836 handled below, if we are converting something to its own
7837 type via an object of identical or wider precision, neither
7838 conversion is needed. */
7839 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
7840 && (((inter_int || inter_ptr) && final_int)
7841 || (inter_float && final_float))
7842 && inter_prec >= final_prec)
7843 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7845 /* Likewise, if the intermediate and initial types are either both
7846 float or both integer, we don't need the middle conversion if the
7847 former is wider than the latter and doesn't change the signedness
7848 (for integers). Avoid this if the final type is a pointer since
7849 then we sometimes need the middle conversion. Likewise if the
7850 final type has a precision not equal to the size of its mode. */
7851 if (((inter_int && inside_int)
7852 || (inter_float && inside_float)
7853 || (inter_vec && inside_vec))
7854 && inter_prec >= inside_prec
7855 && (inter_float || inter_vec
7856 || inter_unsignedp == inside_unsignedp)
7857 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7858 && TYPE_MODE (type) == TYPE_MODE (inter_type))
7860 && (! final_vec || inter_prec == inside_prec))
7861 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7863 /* If we have a sign-extension of a zero-extended value, we can
7864 replace that by a single zero-extension. */
7865 if (inside_int && inter_int && final_int
7866 && inside_prec < inter_prec && inter_prec < final_prec
7867 && inside_unsignedp && !inter_unsignedp)
7868 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7870 /* Two conversions in a row are not needed unless:
7871 - some conversion is floating-point (overstrict for now), or
7872 - some conversion is a vector (overstrict for now), or
7873 - the intermediate type is narrower than both initial and
7875 - the intermediate type and innermost type differ in signedness,
7876 and the outermost type is wider than the intermediate, or
7877 - the initial type is a pointer type and the precisions of the
7878 intermediate and final types differ, or
7879 - the final type is a pointer type and the precisions of the
7880 initial and intermediate types differ. */
7881 if (! inside_float && ! inter_float && ! final_float
7882 && ! inside_vec && ! inter_vec && ! final_vec
7883 && (inter_prec >= inside_prec || inter_prec >= final_prec)
7884 && ! (inside_int && inter_int
7885 && inter_unsignedp != inside_unsignedp
7886 && inter_prec < final_prec)
7887 && ((inter_unsignedp && inter_prec > inside_prec)
7888 == (final_unsignedp && final_prec > inter_prec))
7889 && ! (inside_ptr && inter_prec != final_prec)
7890 && ! (final_ptr && inside_prec != inter_prec)
7891 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7892 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
7893 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7896 /* Handle (T *)&A.B.C for A being of type T and B and C
7897 living at offset zero. This occurs frequently in
7898 C++ upcasting and then accessing the base. */
7899 if (TREE_CODE (op0) == ADDR_EXPR
7900 && POINTER_TYPE_P (type)
7901 && handled_component_p (TREE_OPERAND (op0, 0)))
7903 HOST_WIDE_INT bitsize, bitpos;
7905 enum machine_mode mode;
7906 int unsignedp, volatilep;
7907 tree base = TREE_OPERAND (op0, 0);
7908 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
7909 &mode, &unsignedp, &volatilep, false);
7910 /* If the reference was to a (constant) zero offset, we can use
7911 the address of the base if it has the same base type
7912 as the result type and the pointer type is unqualified. */
7913 if (! offset && bitpos == 0
7914 && (TYPE_MAIN_VARIANT (TREE_TYPE (type))
7915 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
7916 && TYPE_QUALS (type) == TYPE_UNQUALIFIED)
7917 return fold_convert_loc (loc, type,
7918 build_fold_addr_expr_loc (loc, base));
7921 if (TREE_CODE (op0) == MODIFY_EXPR
7922 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
7923 /* Detect assigning a bitfield. */
7924 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
7926 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
7928 /* Don't leave an assignment inside a conversion
7929 unless assigning a bitfield. */
7930 tem = fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 1));
7931 /* First do the assignment, then return converted constant. */
7932 tem = build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
7933 TREE_NO_WARNING (tem) = 1;
7934 TREE_USED (tem) = 1;
7938 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
7939 constants (if x has signed type, the sign bit cannot be set
7940 in c). This folds extension into the BIT_AND_EXPR.
7941 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
7942 very likely don't have maximal range for their precision and this
7943 transformation effectively doesn't preserve non-maximal ranges. */
7944 if (TREE_CODE (type) == INTEGER_TYPE
7945 && TREE_CODE (op0) == BIT_AND_EXPR
7946 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
7948 tree and_expr = op0;
7949 tree and0 = TREE_OPERAND (and_expr, 0);
7950 tree and1 = TREE_OPERAND (and_expr, 1);
7953 if (TYPE_UNSIGNED (TREE_TYPE (and_expr))
7954 || (TYPE_PRECISION (type)
7955 <= TYPE_PRECISION (TREE_TYPE (and_expr))))
7957 else if (TYPE_PRECISION (TREE_TYPE (and1))
7958 <= HOST_BITS_PER_WIDE_INT
7959 && host_integerp (and1, 1))
7961 unsigned HOST_WIDE_INT cst;
7963 cst = tree_low_cst (and1, 1);
7964 cst &= (HOST_WIDE_INT) -1
7965 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
7966 change = (cst == 0);
7967 #ifdef LOAD_EXTEND_OP
7969 && !flag_syntax_only
7970 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
7973 tree uns = unsigned_type_for (TREE_TYPE (and0));
7974 and0 = fold_convert_loc (loc, uns, and0);
7975 and1 = fold_convert_loc (loc, uns, and1);
7981 tem = force_fit_type_double (type, tree_to_double_int (and1),
7982 0, TREE_OVERFLOW (and1));
7983 return fold_build2_loc (loc, BIT_AND_EXPR, type,
7984 fold_convert_loc (loc, type, and0), tem);
7988 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
7989 when one of the new casts will fold away. Conservatively we assume
7990 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
7991 if (POINTER_TYPE_P (type)
7992 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
7993 && (!TYPE_RESTRICT (type) || TYPE_RESTRICT (TREE_TYPE (arg0)))
7994 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
7995 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
7996 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
7998 tree arg00 = TREE_OPERAND (arg0, 0);
7999 tree arg01 = TREE_OPERAND (arg0, 1);
8001 return fold_build_pointer_plus_loc
8002 (loc, fold_convert_loc (loc, type, arg00), arg01);
8005 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8006 of the same precision, and X is an integer type not narrower than
8007 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8008 if (INTEGRAL_TYPE_P (type)
8009 && TREE_CODE (op0) == BIT_NOT_EXPR
8010 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8011 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
8012 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8014 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
8015 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8016 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
8017 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
8018 fold_convert_loc (loc, type, tem));
8021 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
8022 type of X and Y (integer types only). */
8023 if (INTEGRAL_TYPE_P (type)
8024 && TREE_CODE (op0) == MULT_EXPR
8025 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8026 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
8028 /* Be careful not to introduce new overflows. */
8030 if (TYPE_OVERFLOW_WRAPS (type))
8033 mult_type = unsigned_type_for (type);
8035 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8037 tem = fold_build2_loc (loc, MULT_EXPR, mult_type,
8038 fold_convert_loc (loc, mult_type,
8039 TREE_OPERAND (op0, 0)),
8040 fold_convert_loc (loc, mult_type,
8041 TREE_OPERAND (op0, 1)));
8042 return fold_convert_loc (loc, type, tem);
8046 tem = fold_convert_const (code, type, op0);
8047 return tem ? tem : NULL_TREE;
8049 case ADDR_SPACE_CONVERT_EXPR:
8050 if (integer_zerop (arg0))
8051 return fold_convert_const (code, type, arg0);
8054 case FIXED_CONVERT_EXPR:
8055 tem = fold_convert_const (code, type, arg0);
8056 return tem ? tem : NULL_TREE;
8058 case VIEW_CONVERT_EXPR:
8059 if (TREE_TYPE (op0) == type)
8061 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8062 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8063 type, TREE_OPERAND (op0, 0));
8064 if (TREE_CODE (op0) == MEM_REF)
8065 return fold_build2_loc (loc, MEM_REF, type,
8066 TREE_OPERAND (op0, 0), TREE_OPERAND (op0, 1));
8068 /* For integral conversions with the same precision or pointer
8069 conversions use a NOP_EXPR instead. */
8070 if ((INTEGRAL_TYPE_P (type)
8071 || POINTER_TYPE_P (type))
8072 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8073 || POINTER_TYPE_P (TREE_TYPE (op0)))
8074 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8075 return fold_convert_loc (loc, type, op0);
8077 /* Strip inner integral conversions that do not change the precision. */
8078 if (CONVERT_EXPR_P (op0)
8079 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8080 || POINTER_TYPE_P (TREE_TYPE (op0)))
8081 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8082 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8083 && (TYPE_PRECISION (TREE_TYPE (op0))
8084 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8085 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8086 type, TREE_OPERAND (op0, 0));
8088 return fold_view_convert_expr (type, op0);
8091 tem = fold_negate_expr (loc, arg0);
8093 return fold_convert_loc (loc, type, tem);
8097 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8098 return fold_abs_const (arg0, type);
8099 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8100 return fold_build1_loc (loc, ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8101 /* Convert fabs((double)float) into (double)fabsf(float). */
8102 else if (TREE_CODE (arg0) == NOP_EXPR
8103 && TREE_CODE (type) == REAL_TYPE)
8105 tree targ0 = strip_float_extensions (arg0);
8107 return fold_convert_loc (loc, type,
8108 fold_build1_loc (loc, ABS_EXPR,
8112 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8113 else if (TREE_CODE (arg0) == ABS_EXPR)
8115 else if (tree_expr_nonnegative_p (arg0))
8118 /* Strip sign ops from argument. */
8119 if (TREE_CODE (type) == REAL_TYPE)
8121 tem = fold_strip_sign_ops (arg0);
8123 return fold_build1_loc (loc, ABS_EXPR, type,
8124 fold_convert_loc (loc, type, tem));
8129 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8130 return fold_convert_loc (loc, type, arg0);
8131 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8133 tree itype = TREE_TYPE (type);
8134 tree rpart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 0));
8135 tree ipart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 1));
8136 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart,
8137 negate_expr (ipart));
8139 if (TREE_CODE (arg0) == COMPLEX_CST)
8141 tree itype = TREE_TYPE (type);
8142 tree rpart = fold_convert_loc (loc, itype, TREE_REALPART (arg0));
8143 tree ipart = fold_convert_loc (loc, itype, TREE_IMAGPART (arg0));
8144 return build_complex (type, rpart, negate_expr (ipart));
8146 if (TREE_CODE (arg0) == CONJ_EXPR)
8147 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8151 if (TREE_CODE (arg0) == INTEGER_CST)
8152 return fold_not_const (arg0, type);
8153 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8154 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8155 /* Convert ~ (-A) to A - 1. */
8156 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8157 return fold_build2_loc (loc, MINUS_EXPR, type,
8158 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)),
8159 build_int_cst (type, 1));
8160 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8161 else if (INTEGRAL_TYPE_P (type)
8162 && ((TREE_CODE (arg0) == MINUS_EXPR
8163 && integer_onep (TREE_OPERAND (arg0, 1)))
8164 || (TREE_CODE (arg0) == PLUS_EXPR
8165 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8166 return fold_build1_loc (loc, NEGATE_EXPR, type,
8167 fold_convert_loc (loc, type,
8168 TREE_OPERAND (arg0, 0)));
8169 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8170 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8171 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8172 fold_convert_loc (loc, type,
8173 TREE_OPERAND (arg0, 0)))))
8174 return fold_build2_loc (loc, BIT_XOR_EXPR, type, tem,
8175 fold_convert_loc (loc, type,
8176 TREE_OPERAND (arg0, 1)));
8177 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8178 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8179 fold_convert_loc (loc, type,
8180 TREE_OPERAND (arg0, 1)))))
8181 return fold_build2_loc (loc, BIT_XOR_EXPR, type,
8182 fold_convert_loc (loc, type,
8183 TREE_OPERAND (arg0, 0)), tem);
8184 /* Perform BIT_NOT_EXPR on each element individually. */
8185 else if (TREE_CODE (arg0) == VECTOR_CST)
8187 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8188 int count = TYPE_VECTOR_SUBPARTS (type), i;
8190 for (i = 0; i < count; i++)
8194 elem = TREE_VALUE (elements);
8195 elem = fold_unary_loc (loc, BIT_NOT_EXPR, TREE_TYPE (type), elem);
8196 if (elem == NULL_TREE)
8198 elements = TREE_CHAIN (elements);
8201 elem = build_int_cst (TREE_TYPE (type), -1);
8202 list = tree_cons (NULL_TREE, elem, list);
8205 return build_vector (type, nreverse (list));
8210 case TRUTH_NOT_EXPR:
8211 /* The argument to invert_truthvalue must have Boolean type. */
8212 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8213 arg0 = fold_convert_loc (loc, boolean_type_node, arg0);
8215 /* Note that the operand of this must be an int
8216 and its values must be 0 or 1.
8217 ("true" is a fixed value perhaps depending on the language,
8218 but we don't handle values other than 1 correctly yet.) */
8219 tem = fold_truth_not_expr (loc, arg0);
8222 return fold_convert_loc (loc, type, tem);
8225 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8226 return fold_convert_loc (loc, type, arg0);
8227 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8228 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
8229 TREE_OPERAND (arg0, 1));
8230 if (TREE_CODE (arg0) == COMPLEX_CST)
8231 return fold_convert_loc (loc, type, TREE_REALPART (arg0));
8232 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8234 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8235 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8236 fold_build1_loc (loc, REALPART_EXPR, itype,
8237 TREE_OPERAND (arg0, 0)),
8238 fold_build1_loc (loc, REALPART_EXPR, itype,
8239 TREE_OPERAND (arg0, 1)));
8240 return fold_convert_loc (loc, type, tem);
8242 if (TREE_CODE (arg0) == CONJ_EXPR)
8244 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8245 tem = fold_build1_loc (loc, REALPART_EXPR, itype,
8246 TREE_OPERAND (arg0, 0));
8247 return fold_convert_loc (loc, type, tem);
8249 if (TREE_CODE (arg0) == CALL_EXPR)
8251 tree fn = get_callee_fndecl (arg0);
8252 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8253 switch (DECL_FUNCTION_CODE (fn))
8255 CASE_FLT_FN (BUILT_IN_CEXPI):
8256 fn = mathfn_built_in (type, BUILT_IN_COS);
8258 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8268 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8269 return build_zero_cst (type);
8270 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8271 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 1),
8272 TREE_OPERAND (arg0, 0));
8273 if (TREE_CODE (arg0) == COMPLEX_CST)
8274 return fold_convert_loc (loc, type, TREE_IMAGPART (arg0));
8275 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8277 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8278 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8279 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8280 TREE_OPERAND (arg0, 0)),
8281 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8282 TREE_OPERAND (arg0, 1)));
8283 return fold_convert_loc (loc, type, tem);
8285 if (TREE_CODE (arg0) == CONJ_EXPR)
8287 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8288 tem = fold_build1_loc (loc, IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8289 return fold_convert_loc (loc, type, negate_expr (tem));
8291 if (TREE_CODE (arg0) == CALL_EXPR)
8293 tree fn = get_callee_fndecl (arg0);
8294 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8295 switch (DECL_FUNCTION_CODE (fn))
8297 CASE_FLT_FN (BUILT_IN_CEXPI):
8298 fn = mathfn_built_in (type, BUILT_IN_SIN);
8300 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8310 /* Fold *&X to X if X is an lvalue. */
8311 if (TREE_CODE (op0) == ADDR_EXPR)
8313 tree op00 = TREE_OPERAND (op0, 0);
8314 if ((TREE_CODE (op00) == VAR_DECL
8315 || TREE_CODE (op00) == PARM_DECL
8316 || TREE_CODE (op00) == RESULT_DECL)
8317 && !TREE_READONLY (op00))
8322 case VEC_UNPACK_LO_EXPR:
8323 case VEC_UNPACK_HI_EXPR:
8324 case VEC_UNPACK_FLOAT_LO_EXPR:
8325 case VEC_UNPACK_FLOAT_HI_EXPR:
8327 unsigned int nelts = TYPE_VECTOR_SUBPARTS (type), i;
8328 tree *elts, vals = NULL_TREE;
8329 enum tree_code subcode;
8331 gcc_assert (TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)) == nelts * 2);
8332 if (TREE_CODE (arg0) != VECTOR_CST)
8335 elts = XALLOCAVEC (tree, nelts * 2);
8336 if (!vec_cst_ctor_to_array (arg0, elts))
8339 if ((!BYTES_BIG_ENDIAN) ^ (code == VEC_UNPACK_LO_EXPR
8340 || code == VEC_UNPACK_FLOAT_LO_EXPR))
8343 if (code == VEC_UNPACK_LO_EXPR || code == VEC_UNPACK_HI_EXPR)
8346 subcode = FLOAT_EXPR;
8348 for (i = 0; i < nelts; i++)
8350 elts[i] = fold_convert_const (subcode, TREE_TYPE (type), elts[i]);
8351 if (elts[i] == NULL_TREE || !CONSTANT_CLASS_P (elts[i]))
8355 for (i = 0; i < nelts; i++)
8356 vals = tree_cons (NULL_TREE, elts[nelts - i - 1], vals);
8357 return build_vector (type, vals);
8362 } /* switch (code) */
8366 /* If the operation was a conversion do _not_ mark a resulting constant
8367 with TREE_OVERFLOW if the original constant was not. These conversions
8368 have implementation defined behavior and retaining the TREE_OVERFLOW
8369 flag here would confuse later passes such as VRP. */
8371 fold_unary_ignore_overflow_loc (location_t loc, enum tree_code code,
8372 tree type, tree op0)
8374 tree res = fold_unary_loc (loc, code, type, op0);
8376 && TREE_CODE (res) == INTEGER_CST
8377 && TREE_CODE (op0) == INTEGER_CST
8378 && CONVERT_EXPR_CODE_P (code))
8379 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8384 /* Fold a binary bitwise/truth expression of code CODE and type TYPE with
8385 operands OP0 and OP1. LOC is the location of the resulting expression.
8386 ARG0 and ARG1 are the NOP_STRIPed results of OP0 and OP1.
8387 Return the folded expression if folding is successful. Otherwise,
8388 return NULL_TREE. */
8390 fold_truth_andor (location_t loc, enum tree_code code, tree type,
8391 tree arg0, tree arg1, tree op0, tree op1)
8395 /* We only do these simplifications if we are optimizing. */
8399 /* Check for things like (A || B) && (A || C). We can convert this
8400 to A || (B && C). Note that either operator can be any of the four
8401 truth and/or operations and the transformation will still be
8402 valid. Also note that we only care about order for the
8403 ANDIF and ORIF operators. If B contains side effects, this
8404 might change the truth-value of A. */
8405 if (TREE_CODE (arg0) == TREE_CODE (arg1)
8406 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
8407 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
8408 || TREE_CODE (arg0) == TRUTH_AND_EXPR
8409 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
8410 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
8412 tree a00 = TREE_OPERAND (arg0, 0);
8413 tree a01 = TREE_OPERAND (arg0, 1);
8414 tree a10 = TREE_OPERAND (arg1, 0);
8415 tree a11 = TREE_OPERAND (arg1, 1);
8416 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
8417 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
8418 && (code == TRUTH_AND_EXPR
8419 || code == TRUTH_OR_EXPR));
8421 if (operand_equal_p (a00, a10, 0))
8422 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
8423 fold_build2_loc (loc, code, type, a01, a11));
8424 else if (commutative && operand_equal_p (a00, a11, 0))
8425 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
8426 fold_build2_loc (loc, code, type, a01, a10));
8427 else if (commutative && operand_equal_p (a01, a10, 0))
8428 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
8429 fold_build2_loc (loc, code, type, a00, a11));
8431 /* This case if tricky because we must either have commutative
8432 operators or else A10 must not have side-effects. */
8434 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
8435 && operand_equal_p (a01, a11, 0))
8436 return fold_build2_loc (loc, TREE_CODE (arg0), type,
8437 fold_build2_loc (loc, code, type, a00, a10),
8441 /* See if we can build a range comparison. */
8442 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
8445 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg0) == TRUTH_ORIF_EXPR)
8446 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg0) == TRUTH_ANDIF_EXPR))
8448 tem = merge_truthop_with_opposite_arm (loc, arg0, arg1, true);
8450 return fold_build2_loc (loc, code, type, tem, arg1);
8453 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg1) == TRUTH_ORIF_EXPR)
8454 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg1) == TRUTH_ANDIF_EXPR))
8456 tem = merge_truthop_with_opposite_arm (loc, arg1, arg0, false);
8458 return fold_build2_loc (loc, code, type, arg0, tem);
8461 /* Check for the possibility of merging component references. If our
8462 lhs is another similar operation, try to merge its rhs with our
8463 rhs. Then try to merge our lhs and rhs. */
8464 if (TREE_CODE (arg0) == code
8465 && 0 != (tem = fold_truth_andor_1 (loc, code, type,
8466 TREE_OPERAND (arg0, 1), arg1)))
8467 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
8469 if ((tem = fold_truth_andor_1 (loc, code, type, arg0, arg1)) != 0)
8472 if ((BRANCH_COST (optimize_function_for_speed_p (cfun),
8474 && LOGICAL_OP_NON_SHORT_CIRCUIT
8475 && (code == TRUTH_AND_EXPR
8476 || code == TRUTH_ANDIF_EXPR
8477 || code == TRUTH_OR_EXPR
8478 || code == TRUTH_ORIF_EXPR))
8480 enum tree_code ncode, icode;
8482 ncode = (code == TRUTH_ANDIF_EXPR || code == TRUTH_AND_EXPR)
8483 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR;
8484 icode = ncode == TRUTH_AND_EXPR ? TRUTH_ANDIF_EXPR : TRUTH_ORIF_EXPR;
8486 /* Transform ((A AND-IF B) AND[-IF] C) into (A AND-IF (B AND C)),
8487 or ((A OR-IF B) OR[-IF] C) into (A OR-IF (B OR C))
8488 We don't want to pack more than two leafs to a non-IF AND/OR
8490 If tree-code of left-hand operand isn't an AND/OR-IF code and not
8491 equal to IF-CODE, then we don't want to add right-hand operand.
8492 If the inner right-hand side of left-hand operand has
8493 side-effects, or isn't simple, then we can't add to it,
8494 as otherwise we might destroy if-sequence. */
8495 if (TREE_CODE (arg0) == icode
8496 && simple_operand_p_2 (arg1)
8497 /* Needed for sequence points to handle trappings, and
8499 && simple_operand_p_2 (TREE_OPERAND (arg0, 1)))
8501 tem = fold_build2_loc (loc, ncode, type, TREE_OPERAND (arg0, 1),
8503 return fold_build2_loc (loc, icode, type, TREE_OPERAND (arg0, 0),
8506 /* Same as abouve but for (A AND[-IF] (B AND-IF C)) -> ((A AND B) AND-IF C),
8507 or (A OR[-IF] (B OR-IF C) -> ((A OR B) OR-IF C). */
8508 else if (TREE_CODE (arg1) == icode
8509 && simple_operand_p_2 (arg0)
8510 /* Needed for sequence points to handle trappings, and
8512 && simple_operand_p_2 (TREE_OPERAND (arg1, 0)))
8514 tem = fold_build2_loc (loc, ncode, type,
8515 arg0, TREE_OPERAND (arg1, 0));
8516 return fold_build2_loc (loc, icode, type, tem,
8517 TREE_OPERAND (arg1, 1));
8519 /* Transform (A AND-IF B) into (A AND B), or (A OR-IF B)
8521 For sequence point consistancy, we need to check for trapping,
8522 and side-effects. */
8523 else if (code == icode && simple_operand_p_2 (arg0)
8524 && simple_operand_p_2 (arg1))
8525 return fold_build2_loc (loc, ncode, type, arg0, arg1);
8531 /* Fold a binary expression of code CODE and type TYPE with operands
8532 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8533 Return the folded expression if folding is successful. Otherwise,
8534 return NULL_TREE. */
8537 fold_minmax (location_t loc, enum tree_code code, tree type, tree op0, tree op1)
8539 enum tree_code compl_code;
8541 if (code == MIN_EXPR)
8542 compl_code = MAX_EXPR;
8543 else if (code == MAX_EXPR)
8544 compl_code = MIN_EXPR;
8548 /* MIN (MAX (a, b), b) == b. */
8549 if (TREE_CODE (op0) == compl_code
8550 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8551 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 0));
8553 /* MIN (MAX (b, a), b) == b. */
8554 if (TREE_CODE (op0) == compl_code
8555 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8556 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8557 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 1));
8559 /* MIN (a, MAX (a, b)) == a. */
8560 if (TREE_CODE (op1) == compl_code
8561 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8562 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8563 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 1));
8565 /* MIN (a, MAX (b, a)) == a. */
8566 if (TREE_CODE (op1) == compl_code
8567 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8568 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8569 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 0));
8574 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8575 by changing CODE to reduce the magnitude of constants involved in
8576 ARG0 of the comparison.
8577 Returns a canonicalized comparison tree if a simplification was
8578 possible, otherwise returns NULL_TREE.
8579 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8580 valid if signed overflow is undefined. */
8583 maybe_canonicalize_comparison_1 (location_t loc, enum tree_code code, tree type,
8584 tree arg0, tree arg1,
8585 bool *strict_overflow_p)
8587 enum tree_code code0 = TREE_CODE (arg0);
8588 tree t, cst0 = NULL_TREE;
8592 /* Match A +- CST code arg1 and CST code arg1. We can change the
8593 first form only if overflow is undefined. */
8594 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8595 /* In principle pointers also have undefined overflow behavior,
8596 but that causes problems elsewhere. */
8597 && !POINTER_TYPE_P (TREE_TYPE (arg0))
8598 && (code0 == MINUS_EXPR
8599 || code0 == PLUS_EXPR)
8600 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8601 || code0 == INTEGER_CST))
8604 /* Identify the constant in arg0 and its sign. */
8605 if (code0 == INTEGER_CST)
8608 cst0 = TREE_OPERAND (arg0, 1);
8609 sgn0 = tree_int_cst_sgn (cst0);
8611 /* Overflowed constants and zero will cause problems. */
8612 if (integer_zerop (cst0)
8613 || TREE_OVERFLOW (cst0))
8616 /* See if we can reduce the magnitude of the constant in
8617 arg0 by changing the comparison code. */
8618 if (code0 == INTEGER_CST)
8620 /* CST <= arg1 -> CST-1 < arg1. */
8621 if (code == LE_EXPR && sgn0 == 1)
8623 /* -CST < arg1 -> -CST-1 <= arg1. */
8624 else if (code == LT_EXPR && sgn0 == -1)
8626 /* CST > arg1 -> CST-1 >= arg1. */
8627 else if (code == GT_EXPR && sgn0 == 1)
8629 /* -CST >= arg1 -> -CST-1 > arg1. */
8630 else if (code == GE_EXPR && sgn0 == -1)
8634 /* arg1 code' CST' might be more canonical. */
8639 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8641 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8643 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8644 else if (code == GT_EXPR
8645 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8647 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8648 else if (code == LE_EXPR
8649 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8651 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8652 else if (code == GE_EXPR
8653 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8657 *strict_overflow_p = true;
8660 /* Now build the constant reduced in magnitude. But not if that
8661 would produce one outside of its types range. */
8662 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
8664 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
8665 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
8667 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
8668 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
8669 /* We cannot swap the comparison here as that would cause us to
8670 endlessly recurse. */
8673 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8674 cst0, build_int_cst (TREE_TYPE (cst0), 1));
8675 if (code0 != INTEGER_CST)
8676 t = fold_build2_loc (loc, code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8677 t = fold_convert (TREE_TYPE (arg1), t);
8679 /* If swapping might yield to a more canonical form, do so. */
8681 return fold_build2_loc (loc, swap_tree_comparison (code), type, arg1, t);
8683 return fold_build2_loc (loc, code, type, t, arg1);
8686 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8687 overflow further. Try to decrease the magnitude of constants involved
8688 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8689 and put sole constants at the second argument position.
8690 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8693 maybe_canonicalize_comparison (location_t loc, enum tree_code code, tree type,
8694 tree arg0, tree arg1)
8697 bool strict_overflow_p;
8698 const char * const warnmsg = G_("assuming signed overflow does not occur "
8699 "when reducing constant in comparison");
8701 /* Try canonicalization by simplifying arg0. */
8702 strict_overflow_p = false;
8703 t = maybe_canonicalize_comparison_1 (loc, code, type, arg0, arg1,
8704 &strict_overflow_p);
8707 if (strict_overflow_p)
8708 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8712 /* Try canonicalization by simplifying arg1 using the swapped
8714 code = swap_tree_comparison (code);
8715 strict_overflow_p = false;
8716 t = maybe_canonicalize_comparison_1 (loc, code, type, arg1, arg0,
8717 &strict_overflow_p);
8718 if (t && strict_overflow_p)
8719 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8723 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8724 space. This is used to avoid issuing overflow warnings for
8725 expressions like &p->x which can not wrap. */
8728 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8730 unsigned HOST_WIDE_INT offset_low, total_low;
8731 HOST_WIDE_INT size, offset_high, total_high;
8733 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8739 if (offset == NULL_TREE)
8744 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8748 offset_low = TREE_INT_CST_LOW (offset);
8749 offset_high = TREE_INT_CST_HIGH (offset);
8752 if (add_double_with_sign (offset_low, offset_high,
8753 bitpos / BITS_PER_UNIT, 0,
8754 &total_low, &total_high,
8758 if (total_high != 0)
8761 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8765 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8767 if (TREE_CODE (base) == ADDR_EXPR)
8769 HOST_WIDE_INT base_size;
8771 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8772 if (base_size > 0 && size < base_size)
8776 return total_low > (unsigned HOST_WIDE_INT) size;
8779 /* Subroutine of fold_binary. This routine performs all of the
8780 transformations that are common to the equality/inequality
8781 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8782 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8783 fold_binary should call fold_binary. Fold a comparison with
8784 tree code CODE and type TYPE with operands OP0 and OP1. Return
8785 the folded comparison or NULL_TREE. */
8788 fold_comparison (location_t loc, enum tree_code code, tree type,
8791 tree arg0, arg1, tem;
8796 STRIP_SIGN_NOPS (arg0);
8797 STRIP_SIGN_NOPS (arg1);
8799 tem = fold_relational_const (code, type, arg0, arg1);
8800 if (tem != NULL_TREE)
8803 /* If one arg is a real or integer constant, put it last. */
8804 if (tree_swap_operands_p (arg0, arg1, true))
8805 return fold_build2_loc (loc, swap_tree_comparison (code), type, op1, op0);
8807 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8808 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8809 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8810 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8811 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8812 && (TREE_CODE (arg1) == INTEGER_CST
8813 && !TREE_OVERFLOW (arg1)))
8815 tree const1 = TREE_OPERAND (arg0, 1);
8817 tree variable = TREE_OPERAND (arg0, 0);
8820 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8822 lhs = fold_build2_loc (loc, lhs_add ? PLUS_EXPR : MINUS_EXPR,
8823 TREE_TYPE (arg1), const2, const1);
8825 /* If the constant operation overflowed this can be
8826 simplified as a comparison against INT_MAX/INT_MIN. */
8827 if (TREE_CODE (lhs) == INTEGER_CST
8828 && TREE_OVERFLOW (lhs))
8830 int const1_sgn = tree_int_cst_sgn (const1);
8831 enum tree_code code2 = code;
8833 /* Get the sign of the constant on the lhs if the
8834 operation were VARIABLE + CONST1. */
8835 if (TREE_CODE (arg0) == MINUS_EXPR)
8836 const1_sgn = -const1_sgn;
8838 /* The sign of the constant determines if we overflowed
8839 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8840 Canonicalize to the INT_MIN overflow by swapping the comparison
8842 if (const1_sgn == -1)
8843 code2 = swap_tree_comparison (code);
8845 /* We now can look at the canonicalized case
8846 VARIABLE + 1 CODE2 INT_MIN
8847 and decide on the result. */
8848 if (code2 == LT_EXPR
8850 || code2 == EQ_EXPR)
8851 return omit_one_operand_loc (loc, type, boolean_false_node, variable);
8852 else if (code2 == NE_EXPR
8854 || code2 == GT_EXPR)
8855 return omit_one_operand_loc (loc, type, boolean_true_node, variable);
8858 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8859 && (TREE_CODE (lhs) != INTEGER_CST
8860 || !TREE_OVERFLOW (lhs)))
8862 if (code != EQ_EXPR && code != NE_EXPR)
8863 fold_overflow_warning ("assuming signed overflow does not occur "
8864 "when changing X +- C1 cmp C2 to "
8866 WARN_STRICT_OVERFLOW_COMPARISON);
8867 return fold_build2_loc (loc, code, type, variable, lhs);
8871 /* For comparisons of pointers we can decompose it to a compile time
8872 comparison of the base objects and the offsets into the object.
8873 This requires at least one operand being an ADDR_EXPR or a
8874 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8875 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8876 && (TREE_CODE (arg0) == ADDR_EXPR
8877 || TREE_CODE (arg1) == ADDR_EXPR
8878 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8879 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8881 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8882 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8883 enum machine_mode mode;
8884 int volatilep, unsignedp;
8885 bool indirect_base0 = false, indirect_base1 = false;
8887 /* Get base and offset for the access. Strip ADDR_EXPR for
8888 get_inner_reference, but put it back by stripping INDIRECT_REF
8889 off the base object if possible. indirect_baseN will be true
8890 if baseN is not an address but refers to the object itself. */
8892 if (TREE_CODE (arg0) == ADDR_EXPR)
8894 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8895 &bitsize, &bitpos0, &offset0, &mode,
8896 &unsignedp, &volatilep, false);
8897 if (TREE_CODE (base0) == INDIRECT_REF)
8898 base0 = TREE_OPERAND (base0, 0);
8900 indirect_base0 = true;
8902 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
8904 base0 = TREE_OPERAND (arg0, 0);
8905 STRIP_SIGN_NOPS (base0);
8906 if (TREE_CODE (base0) == ADDR_EXPR)
8908 base0 = TREE_OPERAND (base0, 0);
8909 indirect_base0 = true;
8911 offset0 = TREE_OPERAND (arg0, 1);
8912 if (host_integerp (offset0, 0))
8914 HOST_WIDE_INT off = size_low_cst (offset0);
8915 if ((HOST_WIDE_INT) (((unsigned HOST_WIDE_INT) off)
8917 / BITS_PER_UNIT == (HOST_WIDE_INT) off)
8919 bitpos0 = off * BITS_PER_UNIT;
8920 offset0 = NULL_TREE;
8926 if (TREE_CODE (arg1) == ADDR_EXPR)
8928 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
8929 &bitsize, &bitpos1, &offset1, &mode,
8930 &unsignedp, &volatilep, false);
8931 if (TREE_CODE (base1) == INDIRECT_REF)
8932 base1 = TREE_OPERAND (base1, 0);
8934 indirect_base1 = true;
8936 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
8938 base1 = TREE_OPERAND (arg1, 0);
8939 STRIP_SIGN_NOPS (base1);
8940 if (TREE_CODE (base1) == ADDR_EXPR)
8942 base1 = TREE_OPERAND (base1, 0);
8943 indirect_base1 = true;
8945 offset1 = TREE_OPERAND (arg1, 1);
8946 if (host_integerp (offset1, 0))
8948 HOST_WIDE_INT off = size_low_cst (offset1);
8949 if ((HOST_WIDE_INT) (((unsigned HOST_WIDE_INT) off)
8951 / BITS_PER_UNIT == (HOST_WIDE_INT) off)
8953 bitpos1 = off * BITS_PER_UNIT;
8954 offset1 = NULL_TREE;
8959 /* A local variable can never be pointed to by
8960 the default SSA name of an incoming parameter. */
8961 if ((TREE_CODE (arg0) == ADDR_EXPR
8963 && TREE_CODE (base0) == VAR_DECL
8964 && auto_var_in_fn_p (base0, current_function_decl)
8966 && TREE_CODE (base1) == SSA_NAME
8967 && TREE_CODE (SSA_NAME_VAR (base1)) == PARM_DECL
8968 && SSA_NAME_IS_DEFAULT_DEF (base1))
8969 || (TREE_CODE (arg1) == ADDR_EXPR
8971 && TREE_CODE (base1) == VAR_DECL
8972 && auto_var_in_fn_p (base1, current_function_decl)
8974 && TREE_CODE (base0) == SSA_NAME
8975 && TREE_CODE (SSA_NAME_VAR (base0)) == PARM_DECL
8976 && SSA_NAME_IS_DEFAULT_DEF (base0)))
8978 if (code == NE_EXPR)
8979 return constant_boolean_node (1, type);
8980 else if (code == EQ_EXPR)
8981 return constant_boolean_node (0, type);
8983 /* If we have equivalent bases we might be able to simplify. */
8984 else if (indirect_base0 == indirect_base1
8985 && operand_equal_p (base0, base1, 0))
8987 /* We can fold this expression to a constant if the non-constant
8988 offset parts are equal. */
8989 if ((offset0 == offset1
8990 || (offset0 && offset1
8991 && operand_equal_p (offset0, offset1, 0)))
8994 || (indirect_base0 && DECL_P (base0))
8995 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9000 && bitpos0 != bitpos1
9001 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9002 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9003 fold_overflow_warning (("assuming pointer wraparound does not "
9004 "occur when comparing P +- C1 with "
9006 WARN_STRICT_OVERFLOW_CONDITIONAL);
9011 return constant_boolean_node (bitpos0 == bitpos1, type);
9013 return constant_boolean_node (bitpos0 != bitpos1, type);
9015 return constant_boolean_node (bitpos0 < bitpos1, type);
9017 return constant_boolean_node (bitpos0 <= bitpos1, type);
9019 return constant_boolean_node (bitpos0 >= bitpos1, type);
9021 return constant_boolean_node (bitpos0 > bitpos1, type);
9025 /* We can simplify the comparison to a comparison of the variable
9026 offset parts if the constant offset parts are equal.
9027 Be careful to use signed size type here because otherwise we
9028 mess with array offsets in the wrong way. This is possible
9029 because pointer arithmetic is restricted to retain within an
9030 object and overflow on pointer differences is undefined as of
9031 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
9032 else if (bitpos0 == bitpos1
9033 && ((code == EQ_EXPR || code == NE_EXPR)
9034 || (indirect_base0 && DECL_P (base0))
9035 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9037 /* By converting to signed size type we cover middle-end pointer
9038 arithmetic which operates on unsigned pointer types of size
9039 type size and ARRAY_REF offsets which are properly sign or
9040 zero extended from their type in case it is narrower than
9042 if (offset0 == NULL_TREE)
9043 offset0 = build_int_cst (ssizetype, 0);
9045 offset0 = fold_convert_loc (loc, ssizetype, offset0);
9046 if (offset1 == NULL_TREE)
9047 offset1 = build_int_cst (ssizetype, 0);
9049 offset1 = fold_convert_loc (loc, ssizetype, offset1);
9053 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9054 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9055 fold_overflow_warning (("assuming pointer wraparound does not "
9056 "occur when comparing P +- C1 with "
9058 WARN_STRICT_OVERFLOW_COMPARISON);
9060 return fold_build2_loc (loc, code, type, offset0, offset1);
9063 /* For non-equal bases we can simplify if they are addresses
9064 of local binding decls or constants. */
9065 else if (indirect_base0 && indirect_base1
9066 /* We know that !operand_equal_p (base0, base1, 0)
9067 because the if condition was false. But make
9068 sure two decls are not the same. */
9070 && TREE_CODE (arg0) == ADDR_EXPR
9071 && TREE_CODE (arg1) == ADDR_EXPR
9072 && (((TREE_CODE (base0) == VAR_DECL
9073 || TREE_CODE (base0) == PARM_DECL)
9074 && (targetm.binds_local_p (base0)
9075 || CONSTANT_CLASS_P (base1)))
9076 || CONSTANT_CLASS_P (base0))
9077 && (((TREE_CODE (base1) == VAR_DECL
9078 || TREE_CODE (base1) == PARM_DECL)
9079 && (targetm.binds_local_p (base1)
9080 || CONSTANT_CLASS_P (base0)))
9081 || CONSTANT_CLASS_P (base1)))
9083 if (code == EQ_EXPR)
9084 return omit_two_operands_loc (loc, type, boolean_false_node,
9086 else if (code == NE_EXPR)
9087 return omit_two_operands_loc (loc, type, boolean_true_node,
9090 /* For equal offsets we can simplify to a comparison of the
9092 else if (bitpos0 == bitpos1
9094 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
9096 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
9097 && ((offset0 == offset1)
9098 || (offset0 && offset1
9099 && operand_equal_p (offset0, offset1, 0))))
9102 base0 = build_fold_addr_expr_loc (loc, base0);
9104 base1 = build_fold_addr_expr_loc (loc, base1);
9105 return fold_build2_loc (loc, code, type, base0, base1);
9109 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
9110 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
9111 the resulting offset is smaller in absolute value than the
9113 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9114 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9115 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9116 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9117 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
9118 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9119 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
9121 tree const1 = TREE_OPERAND (arg0, 1);
9122 tree const2 = TREE_OPERAND (arg1, 1);
9123 tree variable1 = TREE_OPERAND (arg0, 0);
9124 tree variable2 = TREE_OPERAND (arg1, 0);
9126 const char * const warnmsg = G_("assuming signed overflow does not "
9127 "occur when combining constants around "
9130 /* Put the constant on the side where it doesn't overflow and is
9131 of lower absolute value than before. */
9132 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9133 ? MINUS_EXPR : PLUS_EXPR,
9135 if (!TREE_OVERFLOW (cst)
9136 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
9138 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9139 return fold_build2_loc (loc, code, type,
9141 fold_build2_loc (loc,
9142 TREE_CODE (arg1), TREE_TYPE (arg1),
9146 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9147 ? MINUS_EXPR : PLUS_EXPR,
9149 if (!TREE_OVERFLOW (cst)
9150 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
9152 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9153 return fold_build2_loc (loc, code, type,
9154 fold_build2_loc (loc, TREE_CODE (arg0), TREE_TYPE (arg0),
9160 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
9161 signed arithmetic case. That form is created by the compiler
9162 often enough for folding it to be of value. One example is in
9163 computing loop trip counts after Operator Strength Reduction. */
9164 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9165 && TREE_CODE (arg0) == MULT_EXPR
9166 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9167 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9168 && integer_zerop (arg1))
9170 tree const1 = TREE_OPERAND (arg0, 1);
9171 tree const2 = arg1; /* zero */
9172 tree variable1 = TREE_OPERAND (arg0, 0);
9173 enum tree_code cmp_code = code;
9175 /* Handle unfolded multiplication by zero. */
9176 if (integer_zerop (const1))
9177 return fold_build2_loc (loc, cmp_code, type, const1, const2);
9179 fold_overflow_warning (("assuming signed overflow does not occur when "
9180 "eliminating multiplication in comparison "
9182 WARN_STRICT_OVERFLOW_COMPARISON);
9184 /* If const1 is negative we swap the sense of the comparison. */
9185 if (tree_int_cst_sgn (const1) < 0)
9186 cmp_code = swap_tree_comparison (cmp_code);
9188 return fold_build2_loc (loc, cmp_code, type, variable1, const2);
9191 tem = maybe_canonicalize_comparison (loc, code, type, arg0, arg1);
9195 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
9197 tree targ0 = strip_float_extensions (arg0);
9198 tree targ1 = strip_float_extensions (arg1);
9199 tree newtype = TREE_TYPE (targ0);
9201 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
9202 newtype = TREE_TYPE (targ1);
9204 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9205 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
9206 return fold_build2_loc (loc, code, type,
9207 fold_convert_loc (loc, newtype, targ0),
9208 fold_convert_loc (loc, newtype, targ1));
9210 /* (-a) CMP (-b) -> b CMP a */
9211 if (TREE_CODE (arg0) == NEGATE_EXPR
9212 && TREE_CODE (arg1) == NEGATE_EXPR)
9213 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg1, 0),
9214 TREE_OPERAND (arg0, 0));
9216 if (TREE_CODE (arg1) == REAL_CST)
9218 REAL_VALUE_TYPE cst;
9219 cst = TREE_REAL_CST (arg1);
9221 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9222 if (TREE_CODE (arg0) == NEGATE_EXPR)
9223 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9224 TREE_OPERAND (arg0, 0),
9225 build_real (TREE_TYPE (arg1),
9226 real_value_negate (&cst)));
9228 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9229 /* a CMP (-0) -> a CMP 0 */
9230 if (REAL_VALUE_MINUS_ZERO (cst))
9231 return fold_build2_loc (loc, code, type, arg0,
9232 build_real (TREE_TYPE (arg1), dconst0));
9234 /* x != NaN is always true, other ops are always false. */
9235 if (REAL_VALUE_ISNAN (cst)
9236 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
9238 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
9239 return omit_one_operand_loc (loc, type, tem, arg0);
9242 /* Fold comparisons against infinity. */
9243 if (REAL_VALUE_ISINF (cst)
9244 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
9246 tem = fold_inf_compare (loc, code, type, arg0, arg1);
9247 if (tem != NULL_TREE)
9252 /* If this is a comparison of a real constant with a PLUS_EXPR
9253 or a MINUS_EXPR of a real constant, we can convert it into a
9254 comparison with a revised real constant as long as no overflow
9255 occurs when unsafe_math_optimizations are enabled. */
9256 if (flag_unsafe_math_optimizations
9257 && TREE_CODE (arg1) == REAL_CST
9258 && (TREE_CODE (arg0) == PLUS_EXPR
9259 || TREE_CODE (arg0) == MINUS_EXPR)
9260 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9261 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9262 ? MINUS_EXPR : PLUS_EXPR,
9263 arg1, TREE_OPERAND (arg0, 1)))
9264 && !TREE_OVERFLOW (tem))
9265 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
9267 /* Likewise, we can simplify a comparison of a real constant with
9268 a MINUS_EXPR whose first operand is also a real constant, i.e.
9269 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9270 floating-point types only if -fassociative-math is set. */
9271 if (flag_associative_math
9272 && TREE_CODE (arg1) == REAL_CST
9273 && TREE_CODE (arg0) == MINUS_EXPR
9274 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9275 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9277 && !TREE_OVERFLOW (tem))
9278 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9279 TREE_OPERAND (arg0, 1), tem);
9281 /* Fold comparisons against built-in math functions. */
9282 if (TREE_CODE (arg1) == REAL_CST
9283 && flag_unsafe_math_optimizations
9284 && ! flag_errno_math)
9286 enum built_in_function fcode = builtin_mathfn_code (arg0);
9288 if (fcode != END_BUILTINS)
9290 tem = fold_mathfn_compare (loc, fcode, code, type, arg0, arg1);
9291 if (tem != NULL_TREE)
9297 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9298 && CONVERT_EXPR_P (arg0))
9300 /* If we are widening one operand of an integer comparison,
9301 see if the other operand is similarly being widened. Perhaps we
9302 can do the comparison in the narrower type. */
9303 tem = fold_widened_comparison (loc, code, type, arg0, arg1);
9307 /* Or if we are changing signedness. */
9308 tem = fold_sign_changed_comparison (loc, code, type, arg0, arg1);
9313 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9314 constant, we can simplify it. */
9315 if (TREE_CODE (arg1) == INTEGER_CST
9316 && (TREE_CODE (arg0) == MIN_EXPR
9317 || TREE_CODE (arg0) == MAX_EXPR)
9318 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9320 tem = optimize_minmax_comparison (loc, code, type, op0, op1);
9325 /* Simplify comparison of something with itself. (For IEEE
9326 floating-point, we can only do some of these simplifications.) */
9327 if (operand_equal_p (arg0, arg1, 0))
9332 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9333 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9334 return constant_boolean_node (1, type);
9339 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9340 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9341 return constant_boolean_node (1, type);
9342 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg1);
9345 /* For NE, we can only do this simplification if integer
9346 or we don't honor IEEE floating point NaNs. */
9347 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9348 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9350 /* ... fall through ... */
9353 return constant_boolean_node (0, type);
9359 /* If we are comparing an expression that just has comparisons
9360 of two integer values, arithmetic expressions of those comparisons,
9361 and constants, we can simplify it. There are only three cases
9362 to check: the two values can either be equal, the first can be
9363 greater, or the second can be greater. Fold the expression for
9364 those three values. Since each value must be 0 or 1, we have
9365 eight possibilities, each of which corresponds to the constant 0
9366 or 1 or one of the six possible comparisons.
9368 This handles common cases like (a > b) == 0 but also handles
9369 expressions like ((x > y) - (y > x)) > 0, which supposedly
9370 occur in macroized code. */
9372 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9374 tree cval1 = 0, cval2 = 0;
9377 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9378 /* Don't handle degenerate cases here; they should already
9379 have been handled anyway. */
9380 && cval1 != 0 && cval2 != 0
9381 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9382 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9383 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9384 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9385 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9386 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9387 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9389 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9390 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9392 /* We can't just pass T to eval_subst in case cval1 or cval2
9393 was the same as ARG1. */
9396 = fold_build2_loc (loc, code, type,
9397 eval_subst (loc, arg0, cval1, maxval,
9401 = fold_build2_loc (loc, code, type,
9402 eval_subst (loc, arg0, cval1, maxval,
9406 = fold_build2_loc (loc, code, type,
9407 eval_subst (loc, arg0, cval1, minval,
9411 /* All three of these results should be 0 or 1. Confirm they are.
9412 Then use those values to select the proper code to use. */
9414 if (TREE_CODE (high_result) == INTEGER_CST
9415 && TREE_CODE (equal_result) == INTEGER_CST
9416 && TREE_CODE (low_result) == INTEGER_CST)
9418 /* Make a 3-bit mask with the high-order bit being the
9419 value for `>', the next for '=', and the low for '<'. */
9420 switch ((integer_onep (high_result) * 4)
9421 + (integer_onep (equal_result) * 2)
9422 + integer_onep (low_result))
9426 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
9447 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
9452 tem = save_expr (build2 (code, type, cval1, cval2));
9453 SET_EXPR_LOCATION (tem, loc);
9456 return fold_build2_loc (loc, code, type, cval1, cval2);
9461 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9462 into a single range test. */
9463 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9464 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9465 && TREE_CODE (arg1) == INTEGER_CST
9466 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9467 && !integer_zerop (TREE_OPERAND (arg0, 1))
9468 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9469 && !TREE_OVERFLOW (arg1))
9471 tem = fold_div_compare (loc, code, type, arg0, arg1);
9472 if (tem != NULL_TREE)
9476 /* Fold ~X op ~Y as Y op X. */
9477 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9478 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9480 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9481 return fold_build2_loc (loc, code, type,
9482 fold_convert_loc (loc, cmp_type,
9483 TREE_OPERAND (arg1, 0)),
9484 TREE_OPERAND (arg0, 0));
9487 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9488 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9489 && TREE_CODE (arg1) == INTEGER_CST)
9491 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9492 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9493 TREE_OPERAND (arg0, 0),
9494 fold_build1_loc (loc, BIT_NOT_EXPR, cmp_type,
9495 fold_convert_loc (loc, cmp_type, arg1)));
9502 /* Subroutine of fold_binary. Optimize complex multiplications of the
9503 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9504 argument EXPR represents the expression "z" of type TYPE. */
9507 fold_mult_zconjz (location_t loc, tree type, tree expr)
9509 tree itype = TREE_TYPE (type);
9510 tree rpart, ipart, tem;
9512 if (TREE_CODE (expr) == COMPLEX_EXPR)
9514 rpart = TREE_OPERAND (expr, 0);
9515 ipart = TREE_OPERAND (expr, 1);
9517 else if (TREE_CODE (expr) == COMPLEX_CST)
9519 rpart = TREE_REALPART (expr);
9520 ipart = TREE_IMAGPART (expr);
9524 expr = save_expr (expr);
9525 rpart = fold_build1_loc (loc, REALPART_EXPR, itype, expr);
9526 ipart = fold_build1_loc (loc, IMAGPART_EXPR, itype, expr);
9529 rpart = save_expr (rpart);
9530 ipart = save_expr (ipart);
9531 tem = fold_build2_loc (loc, PLUS_EXPR, itype,
9532 fold_build2_loc (loc, MULT_EXPR, itype, rpart, rpart),
9533 fold_build2_loc (loc, MULT_EXPR, itype, ipart, ipart));
9534 return fold_build2_loc (loc, COMPLEX_EXPR, type, tem,
9535 build_zero_cst (itype));
9539 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9540 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9541 guarantees that P and N have the same least significant log2(M) bits.
9542 N is not otherwise constrained. In particular, N is not normalized to
9543 0 <= N < M as is common. In general, the precise value of P is unknown.
9544 M is chosen as large as possible such that constant N can be determined.
9546 Returns M and sets *RESIDUE to N.
9548 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9549 account. This is not always possible due to PR 35705.
9552 static unsigned HOST_WIDE_INT
9553 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9554 bool allow_func_align)
9556 enum tree_code code;
9560 code = TREE_CODE (expr);
9561 if (code == ADDR_EXPR)
9563 unsigned int bitalign;
9564 bitalign = get_object_alignment_1 (TREE_OPERAND (expr, 0), residue);
9565 *residue /= BITS_PER_UNIT;
9566 return bitalign / BITS_PER_UNIT;
9568 else if (code == POINTER_PLUS_EXPR)
9571 unsigned HOST_WIDE_INT modulus;
9572 enum tree_code inner_code;
9574 op0 = TREE_OPERAND (expr, 0);
9576 modulus = get_pointer_modulus_and_residue (op0, residue,
9579 op1 = TREE_OPERAND (expr, 1);
9581 inner_code = TREE_CODE (op1);
9582 if (inner_code == INTEGER_CST)
9584 *residue += TREE_INT_CST_LOW (op1);
9587 else if (inner_code == MULT_EXPR)
9589 op1 = TREE_OPERAND (op1, 1);
9590 if (TREE_CODE (op1) == INTEGER_CST)
9592 unsigned HOST_WIDE_INT align;
9594 /* Compute the greatest power-of-2 divisor of op1. */
9595 align = TREE_INT_CST_LOW (op1);
9598 /* If align is non-zero and less than *modulus, replace
9599 *modulus with align., If align is 0, then either op1 is 0
9600 or the greatest power-of-2 divisor of op1 doesn't fit in an
9601 unsigned HOST_WIDE_INT. In either case, no additional
9602 constraint is imposed. */
9604 modulus = MIN (modulus, align);
9611 /* If we get here, we were unable to determine anything useful about the
9616 /* Helper function for fold_vec_perm. Store elements of VECTOR_CST or
9617 CONSTRUCTOR ARG into array ELTS and return true if successful. */
9620 vec_cst_ctor_to_array (tree arg, tree *elts)
9622 unsigned int nelts = TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg)), i;
9624 if (TREE_CODE (arg) == VECTOR_CST)
9628 for (i = 0, t = TREE_VECTOR_CST_ELTS (arg);
9629 i < nelts && t; i++, t = TREE_CHAIN (t))
9630 elts[i] = TREE_VALUE (t);
9634 else if (TREE_CODE (arg) == CONSTRUCTOR)
9636 constructor_elt *elt;
9638 FOR_EACH_VEC_ELT (constructor_elt, CONSTRUCTOR_ELTS (arg), i, elt)
9642 elts[i] = elt->value;
9646 for (; i < nelts; i++)
9648 = fold_convert (TREE_TYPE (TREE_TYPE (arg)), integer_zero_node);
9652 /* Attempt to fold vector permutation of ARG0 and ARG1 vectors using SEL
9653 selector. Return the folded VECTOR_CST or CONSTRUCTOR if successful,
9654 NULL_TREE otherwise. */
9657 fold_vec_perm (tree type, tree arg0, tree arg1, const unsigned char *sel)
9659 unsigned int nelts = TYPE_VECTOR_SUBPARTS (type), i;
9661 bool need_ctor = false;
9663 gcc_assert (TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)) == nelts
9664 && TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg1)) == nelts);
9665 if (TREE_TYPE (TREE_TYPE (arg0)) != TREE_TYPE (type)
9666 || TREE_TYPE (TREE_TYPE (arg1)) != TREE_TYPE (type))
9669 elts = XALLOCAVEC (tree, nelts * 3);
9670 if (!vec_cst_ctor_to_array (arg0, elts)
9671 || !vec_cst_ctor_to_array (arg1, elts + nelts))
9674 for (i = 0; i < nelts; i++)
9676 if (!CONSTANT_CLASS_P (elts[sel[i]]))
9678 elts[i + 2 * nelts] = unshare_expr (elts[sel[i]]);
9683 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, nelts);
9684 for (i = 0; i < nelts; i++)
9685 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, elts[2 * nelts + i]);
9686 return build_constructor (type, v);
9690 tree vals = NULL_TREE;
9691 for (i = 0; i < nelts; i++)
9692 vals = tree_cons (NULL_TREE, elts[3 * nelts - i - 1], vals);
9693 return build_vector (type, vals);
9697 /* Try to fold a pointer difference of type TYPE two address expressions of
9698 array references AREF0 and AREF1 using location LOC. Return a
9699 simplified expression for the difference or NULL_TREE. */
9702 fold_addr_of_array_ref_difference (location_t loc, tree type,
9703 tree aref0, tree aref1)
9705 tree base0 = TREE_OPERAND (aref0, 0);
9706 tree base1 = TREE_OPERAND (aref1, 0);
9707 tree base_offset = build_int_cst (type, 0);
9709 /* If the bases are array references as well, recurse. If the bases
9710 are pointer indirections compute the difference of the pointers.
9711 If the bases are equal, we are set. */
9712 if ((TREE_CODE (base0) == ARRAY_REF
9713 && TREE_CODE (base1) == ARRAY_REF
9715 = fold_addr_of_array_ref_difference (loc, type, base0, base1)))
9716 || (INDIRECT_REF_P (base0)
9717 && INDIRECT_REF_P (base1)
9718 && (base_offset = fold_binary_loc (loc, MINUS_EXPR, type,
9719 TREE_OPERAND (base0, 0),
9720 TREE_OPERAND (base1, 0))))
9721 || operand_equal_p (base0, base1, 0))
9723 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
9724 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
9725 tree esz = fold_convert_loc (loc, type, array_ref_element_size (aref0));
9726 tree diff = build2 (MINUS_EXPR, type, op0, op1);
9727 return fold_build2_loc (loc, PLUS_EXPR, type,
9729 fold_build2_loc (loc, MULT_EXPR, type,
9735 /* Fold a binary expression of code CODE and type TYPE with operands
9736 OP0 and OP1. LOC is the location of the resulting expression.
9737 Return the folded expression if folding is successful. Otherwise,
9738 return NULL_TREE. */
9741 fold_binary_loc (location_t loc,
9742 enum tree_code code, tree type, tree op0, tree op1)
9744 enum tree_code_class kind = TREE_CODE_CLASS (code);
9745 tree arg0, arg1, tem;
9746 tree t1 = NULL_TREE;
9747 bool strict_overflow_p;
9749 gcc_assert (IS_EXPR_CODE_CLASS (kind)
9750 && TREE_CODE_LENGTH (code) == 2
9752 && op1 != NULL_TREE);
9757 /* Strip any conversions that don't change the mode. This is
9758 safe for every expression, except for a comparison expression
9759 because its signedness is derived from its operands. So, in
9760 the latter case, only strip conversions that don't change the
9761 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
9764 Note that this is done as an internal manipulation within the
9765 constant folder, in order to find the simplest representation
9766 of the arguments so that their form can be studied. In any
9767 cases, the appropriate type conversions should be put back in
9768 the tree that will get out of the constant folder. */
9770 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
9772 STRIP_SIGN_NOPS (arg0);
9773 STRIP_SIGN_NOPS (arg1);
9781 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9782 constant but we can't do arithmetic on them. */
9783 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9784 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9785 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9786 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9787 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9788 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9790 if (kind == tcc_binary)
9792 /* Make sure type and arg0 have the same saturating flag. */
9793 gcc_assert (TYPE_SATURATING (type)
9794 == TYPE_SATURATING (TREE_TYPE (arg0)));
9795 tem = const_binop (code, arg0, arg1);
9797 else if (kind == tcc_comparison)
9798 tem = fold_relational_const (code, type, arg0, arg1);
9802 if (tem != NULL_TREE)
9804 if (TREE_TYPE (tem) != type)
9805 tem = fold_convert_loc (loc, type, tem);
9810 /* If this is a commutative operation, and ARG0 is a constant, move it
9811 to ARG1 to reduce the number of tests below. */
9812 if (commutative_tree_code (code)
9813 && tree_swap_operands_p (arg0, arg1, true))
9814 return fold_build2_loc (loc, code, type, op1, op0);
9816 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9818 First check for cases where an arithmetic operation is applied to a
9819 compound, conditional, or comparison operation. Push the arithmetic
9820 operation inside the compound or conditional to see if any folding
9821 can then be done. Convert comparison to conditional for this purpose.
9822 The also optimizes non-constant cases that used to be done in
9825 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9826 one of the operands is a comparison and the other is a comparison, a
9827 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9828 code below would make the expression more complex. Change it to a
9829 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9830 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9832 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9833 || code == EQ_EXPR || code == NE_EXPR)
9834 && ((truth_value_p (TREE_CODE (arg0))
9835 && (truth_value_p (TREE_CODE (arg1))
9836 || (TREE_CODE (arg1) == BIT_AND_EXPR
9837 && integer_onep (TREE_OPERAND (arg1, 1)))))
9838 || (truth_value_p (TREE_CODE (arg1))
9839 && (truth_value_p (TREE_CODE (arg0))
9840 || (TREE_CODE (arg0) == BIT_AND_EXPR
9841 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9843 tem = fold_build2_loc (loc, code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9844 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9847 fold_convert_loc (loc, boolean_type_node, arg0),
9848 fold_convert_loc (loc, boolean_type_node, arg1));
9850 if (code == EQ_EXPR)
9851 tem = invert_truthvalue_loc (loc, tem);
9853 return fold_convert_loc (loc, type, tem);
9856 if (TREE_CODE_CLASS (code) == tcc_binary
9857 || TREE_CODE_CLASS (code) == tcc_comparison)
9859 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9861 tem = fold_build2_loc (loc, code, type,
9862 fold_convert_loc (loc, TREE_TYPE (op0),
9863 TREE_OPERAND (arg0, 1)), op1);
9864 return build2_loc (loc, COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
9867 if (TREE_CODE (arg1) == COMPOUND_EXPR
9868 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9870 tem = fold_build2_loc (loc, code, type, op0,
9871 fold_convert_loc (loc, TREE_TYPE (op1),
9872 TREE_OPERAND (arg1, 1)));
9873 return build2_loc (loc, COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
9877 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9879 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9881 /*cond_first_p=*/1);
9882 if (tem != NULL_TREE)
9886 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9888 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9890 /*cond_first_p=*/0);
9891 if (tem != NULL_TREE)
9899 /* MEM[&MEM[p, CST1], CST2] -> MEM[p, CST1 + CST2]. */
9900 if (TREE_CODE (arg0) == ADDR_EXPR
9901 && TREE_CODE (TREE_OPERAND (arg0, 0)) == MEM_REF)
9903 tree iref = TREE_OPERAND (arg0, 0);
9904 return fold_build2 (MEM_REF, type,
9905 TREE_OPERAND (iref, 0),
9906 int_const_binop (PLUS_EXPR, arg1,
9907 TREE_OPERAND (iref, 1)));
9910 /* MEM[&a.b, CST2] -> MEM[&a, offsetof (a, b) + CST2]. */
9911 if (TREE_CODE (arg0) == ADDR_EXPR
9912 && handled_component_p (TREE_OPERAND (arg0, 0)))
9915 HOST_WIDE_INT coffset;
9916 base = get_addr_base_and_unit_offset (TREE_OPERAND (arg0, 0),
9920 return fold_build2 (MEM_REF, type,
9921 build_fold_addr_expr (base),
9922 int_const_binop (PLUS_EXPR, arg1,
9923 size_int (coffset)));
9928 case POINTER_PLUS_EXPR:
9929 /* 0 +p index -> (type)index */
9930 if (integer_zerop (arg0))
9931 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9933 /* PTR +p 0 -> PTR */
9934 if (integer_zerop (arg1))
9935 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9937 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9938 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9939 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9940 return fold_convert_loc (loc, type,
9941 fold_build2_loc (loc, PLUS_EXPR, sizetype,
9942 fold_convert_loc (loc, sizetype,
9944 fold_convert_loc (loc, sizetype,
9947 /* (PTR +p B) +p A -> PTR +p (B + A) */
9948 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9951 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
9952 tree arg00 = TREE_OPERAND (arg0, 0);
9953 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
9954 arg01, fold_convert_loc (loc, sizetype, arg1));
9955 return fold_convert_loc (loc, type,
9956 fold_build_pointer_plus_loc (loc,
9960 /* PTR_CST +p CST -> CST1 */
9961 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9962 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
9963 fold_convert_loc (loc, type, arg1));
9965 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9966 of the array. Loop optimizer sometimes produce this type of
9968 if (TREE_CODE (arg0) == ADDR_EXPR)
9970 tem = try_move_mult_to_index (loc, arg0,
9971 fold_convert_loc (loc, sizetype, arg1));
9973 return fold_convert_loc (loc, type, tem);
9979 /* A + (-B) -> A - B */
9980 if (TREE_CODE (arg1) == NEGATE_EXPR)
9981 return fold_build2_loc (loc, MINUS_EXPR, type,
9982 fold_convert_loc (loc, type, arg0),
9983 fold_convert_loc (loc, type,
9984 TREE_OPERAND (arg1, 0)));
9985 /* (-A) + B -> B - A */
9986 if (TREE_CODE (arg0) == NEGATE_EXPR
9987 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9988 return fold_build2_loc (loc, MINUS_EXPR, type,
9989 fold_convert_loc (loc, type, arg1),
9990 fold_convert_loc (loc, type,
9991 TREE_OPERAND (arg0, 0)));
9993 if (INTEGRAL_TYPE_P (type))
9995 /* Convert ~A + 1 to -A. */
9996 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9997 && integer_onep (arg1))
9998 return fold_build1_loc (loc, NEGATE_EXPR, type,
9999 fold_convert_loc (loc, type,
10000 TREE_OPERAND (arg0, 0)));
10002 /* ~X + X is -1. */
10003 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10004 && !TYPE_OVERFLOW_TRAPS (type))
10006 tree tem = TREE_OPERAND (arg0, 0);
10009 if (operand_equal_p (tem, arg1, 0))
10011 t1 = build_int_cst_type (type, -1);
10012 return omit_one_operand_loc (loc, type, t1, arg1);
10016 /* X + ~X is -1. */
10017 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10018 && !TYPE_OVERFLOW_TRAPS (type))
10020 tree tem = TREE_OPERAND (arg1, 0);
10023 if (operand_equal_p (arg0, tem, 0))
10025 t1 = build_int_cst_type (type, -1);
10026 return omit_one_operand_loc (loc, type, t1, arg0);
10030 /* X + (X / CST) * -CST is X % CST. */
10031 if (TREE_CODE (arg1) == MULT_EXPR
10032 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10033 && operand_equal_p (arg0,
10034 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
10036 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
10037 tree cst1 = TREE_OPERAND (arg1, 1);
10038 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
10040 if (sum && integer_zerop (sum))
10041 return fold_convert_loc (loc, type,
10042 fold_build2_loc (loc, TRUNC_MOD_EXPR,
10043 TREE_TYPE (arg0), arg0,
10048 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the same or
10049 one. Make sure the type is not saturating and has the signedness of
10050 the stripped operands, as fold_plusminus_mult_expr will re-associate.
10051 ??? The latter condition should use TYPE_OVERFLOW_* flags instead. */
10052 if ((TREE_CODE (arg0) == MULT_EXPR
10053 || TREE_CODE (arg1) == MULT_EXPR)
10054 && !TYPE_SATURATING (type)
10055 && TYPE_UNSIGNED (type) == TYPE_UNSIGNED (TREE_TYPE (arg0))
10056 && TYPE_UNSIGNED (type) == TYPE_UNSIGNED (TREE_TYPE (arg1))
10057 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10059 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10064 if (! FLOAT_TYPE_P (type))
10066 if (integer_zerop (arg1))
10067 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10069 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
10070 with a constant, and the two constants have no bits in common,
10071 we should treat this as a BIT_IOR_EXPR since this may produce more
10072 simplifications. */
10073 if (TREE_CODE (arg0) == BIT_AND_EXPR
10074 && TREE_CODE (arg1) == BIT_AND_EXPR
10075 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10076 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10077 && integer_zerop (const_binop (BIT_AND_EXPR,
10078 TREE_OPERAND (arg0, 1),
10079 TREE_OPERAND (arg1, 1))))
10081 code = BIT_IOR_EXPR;
10085 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
10086 (plus (plus (mult) (mult)) (foo)) so that we can
10087 take advantage of the factoring cases below. */
10088 if (TYPE_OVERFLOW_WRAPS (type)
10089 && (((TREE_CODE (arg0) == PLUS_EXPR
10090 || TREE_CODE (arg0) == MINUS_EXPR)
10091 && TREE_CODE (arg1) == MULT_EXPR)
10092 || ((TREE_CODE (arg1) == PLUS_EXPR
10093 || TREE_CODE (arg1) == MINUS_EXPR)
10094 && TREE_CODE (arg0) == MULT_EXPR)))
10096 tree parg0, parg1, parg, marg;
10097 enum tree_code pcode;
10099 if (TREE_CODE (arg1) == MULT_EXPR)
10100 parg = arg0, marg = arg1;
10102 parg = arg1, marg = arg0;
10103 pcode = TREE_CODE (parg);
10104 parg0 = TREE_OPERAND (parg, 0);
10105 parg1 = TREE_OPERAND (parg, 1);
10106 STRIP_NOPS (parg0);
10107 STRIP_NOPS (parg1);
10109 if (TREE_CODE (parg0) == MULT_EXPR
10110 && TREE_CODE (parg1) != MULT_EXPR)
10111 return fold_build2_loc (loc, pcode, type,
10112 fold_build2_loc (loc, PLUS_EXPR, type,
10113 fold_convert_loc (loc, type,
10115 fold_convert_loc (loc, type,
10117 fold_convert_loc (loc, type, parg1));
10118 if (TREE_CODE (parg0) != MULT_EXPR
10119 && TREE_CODE (parg1) == MULT_EXPR)
10121 fold_build2_loc (loc, PLUS_EXPR, type,
10122 fold_convert_loc (loc, type, parg0),
10123 fold_build2_loc (loc, pcode, type,
10124 fold_convert_loc (loc, type, marg),
10125 fold_convert_loc (loc, type,
10131 /* See if ARG1 is zero and X + ARG1 reduces to X. */
10132 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
10133 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10135 /* Likewise if the operands are reversed. */
10136 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10137 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
10139 /* Convert X + -C into X - C. */
10140 if (TREE_CODE (arg1) == REAL_CST
10141 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
10143 tem = fold_negate_const (arg1, type);
10144 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
10145 return fold_build2_loc (loc, MINUS_EXPR, type,
10146 fold_convert_loc (loc, type, arg0),
10147 fold_convert_loc (loc, type, tem));
10150 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
10151 to __complex__ ( x, y ). This is not the same for SNaNs or
10152 if signed zeros are involved. */
10153 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10154 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10155 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10157 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10158 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10159 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10160 bool arg0rz = false, arg0iz = false;
10161 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10162 || (arg0i && (arg0iz = real_zerop (arg0i))))
10164 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10165 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10166 if (arg0rz && arg1i && real_zerop (arg1i))
10168 tree rp = arg1r ? arg1r
10169 : build1 (REALPART_EXPR, rtype, arg1);
10170 tree ip = arg0i ? arg0i
10171 : build1 (IMAGPART_EXPR, rtype, arg0);
10172 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10174 else if (arg0iz && arg1r && real_zerop (arg1r))
10176 tree rp = arg0r ? arg0r
10177 : build1 (REALPART_EXPR, rtype, arg0);
10178 tree ip = arg1i ? arg1i
10179 : build1 (IMAGPART_EXPR, rtype, arg1);
10180 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10185 if (flag_unsafe_math_optimizations
10186 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10187 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10188 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10191 /* Convert x+x into x*2.0. */
10192 if (operand_equal_p (arg0, arg1, 0)
10193 && SCALAR_FLOAT_TYPE_P (type))
10194 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
10195 build_real (type, dconst2));
10197 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
10198 We associate floats only if the user has specified
10199 -fassociative-math. */
10200 if (flag_associative_math
10201 && TREE_CODE (arg1) == PLUS_EXPR
10202 && TREE_CODE (arg0) != MULT_EXPR)
10204 tree tree10 = TREE_OPERAND (arg1, 0);
10205 tree tree11 = TREE_OPERAND (arg1, 1);
10206 if (TREE_CODE (tree11) == MULT_EXPR
10207 && TREE_CODE (tree10) == MULT_EXPR)
10210 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
10211 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
10214 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
10215 We associate floats only if the user has specified
10216 -fassociative-math. */
10217 if (flag_associative_math
10218 && TREE_CODE (arg0) == PLUS_EXPR
10219 && TREE_CODE (arg1) != MULT_EXPR)
10221 tree tree00 = TREE_OPERAND (arg0, 0);
10222 tree tree01 = TREE_OPERAND (arg0, 1);
10223 if (TREE_CODE (tree01) == MULT_EXPR
10224 && TREE_CODE (tree00) == MULT_EXPR)
10227 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
10228 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
10234 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
10235 is a rotate of A by C1 bits. */
10236 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
10237 is a rotate of A by B bits. */
10239 enum tree_code code0, code1;
10241 code0 = TREE_CODE (arg0);
10242 code1 = TREE_CODE (arg1);
10243 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
10244 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
10245 && operand_equal_p (TREE_OPERAND (arg0, 0),
10246 TREE_OPERAND (arg1, 0), 0)
10247 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
10248 TYPE_UNSIGNED (rtype))
10249 /* Only create rotates in complete modes. Other cases are not
10250 expanded properly. */
10251 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
10253 tree tree01, tree11;
10254 enum tree_code code01, code11;
10256 tree01 = TREE_OPERAND (arg0, 1);
10257 tree11 = TREE_OPERAND (arg1, 1);
10258 STRIP_NOPS (tree01);
10259 STRIP_NOPS (tree11);
10260 code01 = TREE_CODE (tree01);
10261 code11 = TREE_CODE (tree11);
10262 if (code01 == INTEGER_CST
10263 && code11 == INTEGER_CST
10264 && TREE_INT_CST_HIGH (tree01) == 0
10265 && TREE_INT_CST_HIGH (tree11) == 0
10266 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
10267 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
10269 tem = build2_loc (loc, LROTATE_EXPR,
10270 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10271 TREE_OPERAND (arg0, 0),
10272 code0 == LSHIFT_EXPR ? tree01 : tree11);
10273 return fold_convert_loc (loc, type, tem);
10275 else if (code11 == MINUS_EXPR)
10277 tree tree110, tree111;
10278 tree110 = TREE_OPERAND (tree11, 0);
10279 tree111 = TREE_OPERAND (tree11, 1);
10280 STRIP_NOPS (tree110);
10281 STRIP_NOPS (tree111);
10282 if (TREE_CODE (tree110) == INTEGER_CST
10283 && 0 == compare_tree_int (tree110,
10285 (TREE_TYPE (TREE_OPERAND
10287 && operand_equal_p (tree01, tree111, 0))
10289 fold_convert_loc (loc, type,
10290 build2 ((code0 == LSHIFT_EXPR
10293 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10294 TREE_OPERAND (arg0, 0), tree01));
10296 else if (code01 == MINUS_EXPR)
10298 tree tree010, tree011;
10299 tree010 = TREE_OPERAND (tree01, 0);
10300 tree011 = TREE_OPERAND (tree01, 1);
10301 STRIP_NOPS (tree010);
10302 STRIP_NOPS (tree011);
10303 if (TREE_CODE (tree010) == INTEGER_CST
10304 && 0 == compare_tree_int (tree010,
10306 (TREE_TYPE (TREE_OPERAND
10308 && operand_equal_p (tree11, tree011, 0))
10309 return fold_convert_loc
10311 build2 ((code0 != LSHIFT_EXPR
10314 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10315 TREE_OPERAND (arg0, 0), tree11));
10321 /* In most languages, can't associate operations on floats through
10322 parentheses. Rather than remember where the parentheses were, we
10323 don't associate floats at all, unless the user has specified
10324 -fassociative-math.
10325 And, we need to make sure type is not saturating. */
10327 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
10328 && !TYPE_SATURATING (type))
10330 tree var0, con0, lit0, minus_lit0;
10331 tree var1, con1, lit1, minus_lit1;
10334 /* Split both trees into variables, constants, and literals. Then
10335 associate each group together, the constants with literals,
10336 then the result with variables. This increases the chances of
10337 literals being recombined later and of generating relocatable
10338 expressions for the sum of a constant and literal. */
10339 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10340 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10341 code == MINUS_EXPR);
10343 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10344 if (code == MINUS_EXPR)
10347 /* With undefined overflow we can only associate constants with one
10348 variable, and constants whose association doesn't overflow. */
10349 if ((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10350 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10357 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10358 tmp0 = TREE_OPERAND (tmp0, 0);
10359 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10360 tmp1 = TREE_OPERAND (tmp1, 0);
10361 /* The only case we can still associate with two variables
10362 is if they are the same, modulo negation. */
10363 if (!operand_equal_p (tmp0, tmp1, 0))
10367 if (ok && lit0 && lit1)
10369 tree tmp0 = fold_convert (type, lit0);
10370 tree tmp1 = fold_convert (type, lit1);
10372 if (!TREE_OVERFLOW (tmp0) && !TREE_OVERFLOW (tmp1)
10373 && TREE_OVERFLOW (fold_build2 (code, type, tmp0, tmp1)))
10378 /* Only do something if we found more than two objects. Otherwise,
10379 nothing has changed and we risk infinite recursion. */
10381 && (2 < ((var0 != 0) + (var1 != 0)
10382 + (con0 != 0) + (con1 != 0)
10383 + (lit0 != 0) + (lit1 != 0)
10384 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10386 var0 = associate_trees (loc, var0, var1, code, type);
10387 con0 = associate_trees (loc, con0, con1, code, type);
10388 lit0 = associate_trees (loc, lit0, lit1, code, type);
10389 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10391 /* Preserve the MINUS_EXPR if the negative part of the literal is
10392 greater than the positive part. Otherwise, the multiplicative
10393 folding code (i.e extract_muldiv) may be fooled in case
10394 unsigned constants are subtracted, like in the following
10395 example: ((X*2 + 4) - 8U)/2. */
10396 if (minus_lit0 && lit0)
10398 if (TREE_CODE (lit0) == INTEGER_CST
10399 && TREE_CODE (minus_lit0) == INTEGER_CST
10400 && tree_int_cst_lt (lit0, minus_lit0))
10402 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10408 lit0 = associate_trees (loc, lit0, minus_lit0,
10417 fold_convert_loc (loc, type,
10418 associate_trees (loc, var0, minus_lit0,
10419 MINUS_EXPR, type));
10422 con0 = associate_trees (loc, con0, minus_lit0,
10425 fold_convert_loc (loc, type,
10426 associate_trees (loc, var0, con0,
10431 con0 = associate_trees (loc, con0, lit0, code, type);
10433 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10441 /* Pointer simplifications for subtraction, simple reassociations. */
10442 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10444 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10445 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10446 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10448 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10449 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10450 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10451 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10452 return fold_build2_loc (loc, PLUS_EXPR, type,
10453 fold_build2_loc (loc, MINUS_EXPR, type,
10455 fold_build2_loc (loc, MINUS_EXPR, type,
10458 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10459 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10461 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10462 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10463 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10464 fold_convert_loc (loc, type, arg1));
10466 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10469 /* A - (-B) -> A + B */
10470 if (TREE_CODE (arg1) == NEGATE_EXPR)
10471 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10472 fold_convert_loc (loc, type,
10473 TREE_OPERAND (arg1, 0)));
10474 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10475 if (TREE_CODE (arg0) == NEGATE_EXPR
10476 && (FLOAT_TYPE_P (type)
10477 || INTEGRAL_TYPE_P (type))
10478 && negate_expr_p (arg1)
10479 && reorder_operands_p (arg0, arg1))
10480 return fold_build2_loc (loc, MINUS_EXPR, type,
10481 fold_convert_loc (loc, type,
10482 negate_expr (arg1)),
10483 fold_convert_loc (loc, type,
10484 TREE_OPERAND (arg0, 0)));
10485 /* Convert -A - 1 to ~A. */
10486 if (INTEGRAL_TYPE_P (type)
10487 && TREE_CODE (arg0) == NEGATE_EXPR
10488 && integer_onep (arg1)
10489 && !TYPE_OVERFLOW_TRAPS (type))
10490 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10491 fold_convert_loc (loc, type,
10492 TREE_OPERAND (arg0, 0)));
10494 /* Convert -1 - A to ~A. */
10495 if (INTEGRAL_TYPE_P (type)
10496 && integer_all_onesp (arg0))
10497 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10500 /* X - (X / CST) * CST is X % CST. */
10501 if (INTEGRAL_TYPE_P (type)
10502 && TREE_CODE (arg1) == MULT_EXPR
10503 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10504 && operand_equal_p (arg0,
10505 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10506 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10507 TREE_OPERAND (arg1, 1), 0))
10509 fold_convert_loc (loc, type,
10510 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10511 arg0, TREE_OPERAND (arg1, 1)));
10513 if (! FLOAT_TYPE_P (type))
10515 if (integer_zerop (arg0))
10516 return negate_expr (fold_convert_loc (loc, type, arg1));
10517 if (integer_zerop (arg1))
10518 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10520 /* Fold A - (A & B) into ~B & A. */
10521 if (!TREE_SIDE_EFFECTS (arg0)
10522 && TREE_CODE (arg1) == BIT_AND_EXPR)
10524 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10526 tree arg10 = fold_convert_loc (loc, type,
10527 TREE_OPERAND (arg1, 0));
10528 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10529 fold_build1_loc (loc, BIT_NOT_EXPR,
10531 fold_convert_loc (loc, type, arg0));
10533 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10535 tree arg11 = fold_convert_loc (loc,
10536 type, TREE_OPERAND (arg1, 1));
10537 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10538 fold_build1_loc (loc, BIT_NOT_EXPR,
10540 fold_convert_loc (loc, type, arg0));
10544 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10545 any power of 2 minus 1. */
10546 if (TREE_CODE (arg0) == BIT_AND_EXPR
10547 && TREE_CODE (arg1) == BIT_AND_EXPR
10548 && operand_equal_p (TREE_OPERAND (arg0, 0),
10549 TREE_OPERAND (arg1, 0), 0))
10551 tree mask0 = TREE_OPERAND (arg0, 1);
10552 tree mask1 = TREE_OPERAND (arg1, 1);
10553 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10555 if (operand_equal_p (tem, mask1, 0))
10557 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10558 TREE_OPERAND (arg0, 0), mask1);
10559 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10564 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10565 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10566 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10568 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10569 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10570 (-ARG1 + ARG0) reduces to -ARG1. */
10571 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10572 return negate_expr (fold_convert_loc (loc, type, arg1));
10574 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10575 __complex__ ( x, -y ). This is not the same for SNaNs or if
10576 signed zeros are involved. */
10577 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10578 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10579 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10581 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10582 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10583 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10584 bool arg0rz = false, arg0iz = false;
10585 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10586 || (arg0i && (arg0iz = real_zerop (arg0i))))
10588 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10589 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10590 if (arg0rz && arg1i && real_zerop (arg1i))
10592 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10594 : build1 (REALPART_EXPR, rtype, arg1));
10595 tree ip = arg0i ? arg0i
10596 : build1 (IMAGPART_EXPR, rtype, arg0);
10597 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10599 else if (arg0iz && arg1r && real_zerop (arg1r))
10601 tree rp = arg0r ? arg0r
10602 : build1 (REALPART_EXPR, rtype, arg0);
10603 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10605 : build1 (IMAGPART_EXPR, rtype, arg1));
10606 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10611 /* Fold &x - &x. This can happen from &x.foo - &x.
10612 This is unsafe for certain floats even in non-IEEE formats.
10613 In IEEE, it is unsafe because it does wrong for NaNs.
10614 Also note that operand_equal_p is always false if an operand
10617 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10618 && operand_equal_p (arg0, arg1, 0))
10619 return build_zero_cst (type);
10621 /* A - B -> A + (-B) if B is easily negatable. */
10622 if (negate_expr_p (arg1)
10623 && ((FLOAT_TYPE_P (type)
10624 /* Avoid this transformation if B is a positive REAL_CST. */
10625 && (TREE_CODE (arg1) != REAL_CST
10626 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10627 || INTEGRAL_TYPE_P (type)))
10628 return fold_build2_loc (loc, PLUS_EXPR, type,
10629 fold_convert_loc (loc, type, arg0),
10630 fold_convert_loc (loc, type,
10631 negate_expr (arg1)));
10633 /* Try folding difference of addresses. */
10635 HOST_WIDE_INT diff;
10637 if ((TREE_CODE (arg0) == ADDR_EXPR
10638 || TREE_CODE (arg1) == ADDR_EXPR)
10639 && ptr_difference_const (arg0, arg1, &diff))
10640 return build_int_cst_type (type, diff);
10643 /* Fold &a[i] - &a[j] to i-j. */
10644 if (TREE_CODE (arg0) == ADDR_EXPR
10645 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10646 && TREE_CODE (arg1) == ADDR_EXPR
10647 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10649 tree tem = fold_addr_of_array_ref_difference (loc, type,
10650 TREE_OPERAND (arg0, 0),
10651 TREE_OPERAND (arg1, 0));
10656 if (FLOAT_TYPE_P (type)
10657 && flag_unsafe_math_optimizations
10658 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10659 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10660 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10663 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the same or
10664 one. Make sure the type is not saturating and has the signedness of
10665 the stripped operands, as fold_plusminus_mult_expr will re-associate.
10666 ??? The latter condition should use TYPE_OVERFLOW_* flags instead. */
10667 if ((TREE_CODE (arg0) == MULT_EXPR
10668 || TREE_CODE (arg1) == MULT_EXPR)
10669 && !TYPE_SATURATING (type)
10670 && TYPE_UNSIGNED (type) == TYPE_UNSIGNED (TREE_TYPE (arg0))
10671 && TYPE_UNSIGNED (type) == TYPE_UNSIGNED (TREE_TYPE (arg1))
10672 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10674 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10682 /* (-A) * (-B) -> A * B */
10683 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10684 return fold_build2_loc (loc, MULT_EXPR, type,
10685 fold_convert_loc (loc, type,
10686 TREE_OPERAND (arg0, 0)),
10687 fold_convert_loc (loc, type,
10688 negate_expr (arg1)));
10689 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10690 return fold_build2_loc (loc, MULT_EXPR, type,
10691 fold_convert_loc (loc, type,
10692 negate_expr (arg0)),
10693 fold_convert_loc (loc, type,
10694 TREE_OPERAND (arg1, 0)));
10696 if (! FLOAT_TYPE_P (type))
10698 if (integer_zerop (arg1))
10699 return omit_one_operand_loc (loc, type, arg1, arg0);
10700 if (integer_onep (arg1))
10701 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10702 /* Transform x * -1 into -x. Make sure to do the negation
10703 on the original operand with conversions not stripped
10704 because we can only strip non-sign-changing conversions. */
10705 if (integer_all_onesp (arg1))
10706 return fold_convert_loc (loc, type, negate_expr (op0));
10707 /* Transform x * -C into -x * C if x is easily negatable. */
10708 if (TREE_CODE (arg1) == INTEGER_CST
10709 && tree_int_cst_sgn (arg1) == -1
10710 && negate_expr_p (arg0)
10711 && (tem = negate_expr (arg1)) != arg1
10712 && !TREE_OVERFLOW (tem))
10713 return fold_build2_loc (loc, MULT_EXPR, type,
10714 fold_convert_loc (loc, type,
10715 negate_expr (arg0)),
10718 /* (a * (1 << b)) is (a << b) */
10719 if (TREE_CODE (arg1) == LSHIFT_EXPR
10720 && integer_onep (TREE_OPERAND (arg1, 0)))
10721 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
10722 TREE_OPERAND (arg1, 1));
10723 if (TREE_CODE (arg0) == LSHIFT_EXPR
10724 && integer_onep (TREE_OPERAND (arg0, 0)))
10725 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
10726 TREE_OPERAND (arg0, 1));
10728 /* (A + A) * C -> A * 2 * C */
10729 if (TREE_CODE (arg0) == PLUS_EXPR
10730 && TREE_CODE (arg1) == INTEGER_CST
10731 && operand_equal_p (TREE_OPERAND (arg0, 0),
10732 TREE_OPERAND (arg0, 1), 0))
10733 return fold_build2_loc (loc, MULT_EXPR, type,
10734 omit_one_operand_loc (loc, type,
10735 TREE_OPERAND (arg0, 0),
10736 TREE_OPERAND (arg0, 1)),
10737 fold_build2_loc (loc, MULT_EXPR, type,
10738 build_int_cst (type, 2) , arg1));
10740 strict_overflow_p = false;
10741 if (TREE_CODE (arg1) == INTEGER_CST
10742 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10743 &strict_overflow_p)))
10745 if (strict_overflow_p)
10746 fold_overflow_warning (("assuming signed overflow does not "
10747 "occur when simplifying "
10749 WARN_STRICT_OVERFLOW_MISC);
10750 return fold_convert_loc (loc, type, tem);
10753 /* Optimize z * conj(z) for integer complex numbers. */
10754 if (TREE_CODE (arg0) == CONJ_EXPR
10755 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10756 return fold_mult_zconjz (loc, type, arg1);
10757 if (TREE_CODE (arg1) == CONJ_EXPR
10758 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10759 return fold_mult_zconjz (loc, type, arg0);
10763 /* Maybe fold x * 0 to 0. The expressions aren't the same
10764 when x is NaN, since x * 0 is also NaN. Nor are they the
10765 same in modes with signed zeros, since multiplying a
10766 negative value by 0 gives -0, not +0. */
10767 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10768 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10769 && real_zerop (arg1))
10770 return omit_one_operand_loc (loc, type, arg1, arg0);
10771 /* In IEEE floating point, x*1 is not equivalent to x for snans.
10772 Likewise for complex arithmetic with signed zeros. */
10773 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10774 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10775 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10776 && real_onep (arg1))
10777 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10779 /* Transform x * -1.0 into -x. */
10780 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10781 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10782 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10783 && real_minus_onep (arg1))
10784 return fold_convert_loc (loc, type, negate_expr (arg0));
10786 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10787 the result for floating point types due to rounding so it is applied
10788 only if -fassociative-math was specify. */
10789 if (flag_associative_math
10790 && TREE_CODE (arg0) == RDIV_EXPR
10791 && TREE_CODE (arg1) == REAL_CST
10792 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10794 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10797 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
10798 TREE_OPERAND (arg0, 1));
10801 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10802 if (operand_equal_p (arg0, arg1, 0))
10804 tree tem = fold_strip_sign_ops (arg0);
10805 if (tem != NULL_TREE)
10807 tem = fold_convert_loc (loc, type, tem);
10808 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
10812 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10813 This is not the same for NaNs or if signed zeros are
10815 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10816 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10817 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10818 && TREE_CODE (arg1) == COMPLEX_CST
10819 && real_zerop (TREE_REALPART (arg1)))
10821 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10822 if (real_onep (TREE_IMAGPART (arg1)))
10824 fold_build2_loc (loc, COMPLEX_EXPR, type,
10825 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
10827 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
10828 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10830 fold_build2_loc (loc, COMPLEX_EXPR, type,
10831 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
10832 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
10836 /* Optimize z * conj(z) for floating point complex numbers.
10837 Guarded by flag_unsafe_math_optimizations as non-finite
10838 imaginary components don't produce scalar results. */
10839 if (flag_unsafe_math_optimizations
10840 && TREE_CODE (arg0) == CONJ_EXPR
10841 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10842 return fold_mult_zconjz (loc, type, arg1);
10843 if (flag_unsafe_math_optimizations
10844 && TREE_CODE (arg1) == CONJ_EXPR
10845 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10846 return fold_mult_zconjz (loc, type, arg0);
10848 if (flag_unsafe_math_optimizations)
10850 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10851 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10853 /* Optimizations of root(...)*root(...). */
10854 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10857 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10858 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10860 /* Optimize sqrt(x)*sqrt(x) as x. */
10861 if (BUILTIN_SQRT_P (fcode0)
10862 && operand_equal_p (arg00, arg10, 0)
10863 && ! HONOR_SNANS (TYPE_MODE (type)))
10866 /* Optimize root(x)*root(y) as root(x*y). */
10867 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10868 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
10869 return build_call_expr_loc (loc, rootfn, 1, arg);
10872 /* Optimize expN(x)*expN(y) as expN(x+y). */
10873 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10875 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10876 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10877 CALL_EXPR_ARG (arg0, 0),
10878 CALL_EXPR_ARG (arg1, 0));
10879 return build_call_expr_loc (loc, expfn, 1, arg);
10882 /* Optimizations of pow(...)*pow(...). */
10883 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10884 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10885 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10887 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10888 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10889 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10890 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10892 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10893 if (operand_equal_p (arg01, arg11, 0))
10895 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10896 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
10898 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
10901 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10902 if (operand_equal_p (arg00, arg10, 0))
10904 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10905 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10907 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
10911 /* Optimize tan(x)*cos(x) as sin(x). */
10912 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10913 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10914 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10915 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10916 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10917 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10918 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10919 CALL_EXPR_ARG (arg1, 0), 0))
10921 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10923 if (sinfn != NULL_TREE)
10924 return build_call_expr_loc (loc, sinfn, 1,
10925 CALL_EXPR_ARG (arg0, 0));
10928 /* Optimize x*pow(x,c) as pow(x,c+1). */
10929 if (fcode1 == BUILT_IN_POW
10930 || fcode1 == BUILT_IN_POWF
10931 || fcode1 == BUILT_IN_POWL)
10933 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10934 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10935 if (TREE_CODE (arg11) == REAL_CST
10936 && !TREE_OVERFLOW (arg11)
10937 && operand_equal_p (arg0, arg10, 0))
10939 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10943 c = TREE_REAL_CST (arg11);
10944 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10945 arg = build_real (type, c);
10946 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10950 /* Optimize pow(x,c)*x as pow(x,c+1). */
10951 if (fcode0 == BUILT_IN_POW
10952 || fcode0 == BUILT_IN_POWF
10953 || fcode0 == BUILT_IN_POWL)
10955 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10956 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10957 if (TREE_CODE (arg01) == REAL_CST
10958 && !TREE_OVERFLOW (arg01)
10959 && operand_equal_p (arg1, arg00, 0))
10961 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10965 c = TREE_REAL_CST (arg01);
10966 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10967 arg = build_real (type, c);
10968 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
10972 /* Canonicalize x*x as pow(x,2.0), which is expanded as x*x. */
10973 if (!in_gimple_form
10975 && operand_equal_p (arg0, arg1, 0))
10977 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10981 tree arg = build_real (type, dconst2);
10982 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10991 if (integer_all_onesp (arg1))
10992 return omit_one_operand_loc (loc, type, arg1, arg0);
10993 if (integer_zerop (arg1))
10994 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10995 if (operand_equal_p (arg0, arg1, 0))
10996 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10998 /* ~X | X is -1. */
10999 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11000 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11002 t1 = build_zero_cst (type);
11003 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11004 return omit_one_operand_loc (loc, type, t1, arg1);
11007 /* X | ~X is -1. */
11008 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11009 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11011 t1 = build_zero_cst (type);
11012 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11013 return omit_one_operand_loc (loc, type, t1, arg0);
11016 /* Canonicalize (X & C1) | C2. */
11017 if (TREE_CODE (arg0) == BIT_AND_EXPR
11018 && TREE_CODE (arg1) == INTEGER_CST
11019 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11021 double_int c1, c2, c3, msk;
11022 int width = TYPE_PRECISION (type), w;
11023 c1 = tree_to_double_int (TREE_OPERAND (arg0, 1));
11024 c2 = tree_to_double_int (arg1);
11026 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
11027 if (double_int_equal_p (double_int_and (c1, c2), c1))
11028 return omit_one_operand_loc (loc, type, arg1,
11029 TREE_OPERAND (arg0, 0));
11031 msk = double_int_mask (width);
11033 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
11034 if (double_int_zero_p (double_int_and_not (msk,
11035 double_int_ior (c1, c2))))
11036 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11037 TREE_OPERAND (arg0, 0), arg1);
11039 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
11040 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
11041 mode which allows further optimizations. */
11042 c1 = double_int_and (c1, msk);
11043 c2 = double_int_and (c2, msk);
11044 c3 = double_int_and_not (c1, c2);
11045 for (w = BITS_PER_UNIT;
11046 w <= width && w <= HOST_BITS_PER_WIDE_INT;
11049 unsigned HOST_WIDE_INT mask
11050 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
11051 if (((c1.low | c2.low) & mask) == mask
11052 && (c1.low & ~mask) == 0 && c1.high == 0)
11054 c3 = uhwi_to_double_int (mask);
11058 if (!double_int_equal_p (c3, c1))
11059 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11060 fold_build2_loc (loc, BIT_AND_EXPR, type,
11061 TREE_OPERAND (arg0, 0),
11062 double_int_to_tree (type,
11067 /* (X & Y) | Y is (X, Y). */
11068 if (TREE_CODE (arg0) == BIT_AND_EXPR
11069 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11070 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11071 /* (X & Y) | X is (Y, X). */
11072 if (TREE_CODE (arg0) == BIT_AND_EXPR
11073 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11074 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11075 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11076 /* X | (X & Y) is (Y, X). */
11077 if (TREE_CODE (arg1) == BIT_AND_EXPR
11078 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11079 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11080 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11081 /* X | (Y & X) is (Y, X). */
11082 if (TREE_CODE (arg1) == BIT_AND_EXPR
11083 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11084 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11085 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11087 /* (X & ~Y) | (~X & Y) is X ^ Y */
11088 if (TREE_CODE (arg0) == BIT_AND_EXPR
11089 && TREE_CODE (arg1) == BIT_AND_EXPR)
11091 tree a0, a1, l0, l1, n0, n1;
11093 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11094 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11096 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11097 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11099 n0 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l0);
11100 n1 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l1);
11102 if ((operand_equal_p (n0, a0, 0)
11103 && operand_equal_p (n1, a1, 0))
11104 || (operand_equal_p (n0, a1, 0)
11105 && operand_equal_p (n1, a0, 0)))
11106 return fold_build2_loc (loc, BIT_XOR_EXPR, type, l0, n1);
11109 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11110 if (t1 != NULL_TREE)
11113 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
11115 This results in more efficient code for machines without a NAND
11116 instruction. Combine will canonicalize to the first form
11117 which will allow use of NAND instructions provided by the
11118 backend if they exist. */
11119 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11120 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11123 fold_build1_loc (loc, BIT_NOT_EXPR, type,
11124 build2 (BIT_AND_EXPR, type,
11125 fold_convert_loc (loc, type,
11126 TREE_OPERAND (arg0, 0)),
11127 fold_convert_loc (loc, type,
11128 TREE_OPERAND (arg1, 0))));
11131 /* See if this can be simplified into a rotate first. If that
11132 is unsuccessful continue in the association code. */
11136 if (integer_zerop (arg1))
11137 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11138 if (integer_all_onesp (arg1))
11139 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
11140 if (operand_equal_p (arg0, arg1, 0))
11141 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11143 /* ~X ^ X is -1. */
11144 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11145 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11147 t1 = build_zero_cst (type);
11148 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11149 return omit_one_operand_loc (loc, type, t1, arg1);
11152 /* X ^ ~X is -1. */
11153 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11154 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11156 t1 = build_zero_cst (type);
11157 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11158 return omit_one_operand_loc (loc, type, t1, arg0);
11161 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
11162 with a constant, and the two constants have no bits in common,
11163 we should treat this as a BIT_IOR_EXPR since this may produce more
11164 simplifications. */
11165 if (TREE_CODE (arg0) == BIT_AND_EXPR
11166 && TREE_CODE (arg1) == BIT_AND_EXPR
11167 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11168 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
11169 && integer_zerop (const_binop (BIT_AND_EXPR,
11170 TREE_OPERAND (arg0, 1),
11171 TREE_OPERAND (arg1, 1))))
11173 code = BIT_IOR_EXPR;
11177 /* (X | Y) ^ X -> Y & ~ X*/
11178 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11179 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11181 tree t2 = TREE_OPERAND (arg0, 1);
11182 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11184 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11185 fold_convert_loc (loc, type, t2),
11186 fold_convert_loc (loc, type, t1));
11190 /* (Y | X) ^ X -> Y & ~ X*/
11191 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11192 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11194 tree t2 = TREE_OPERAND (arg0, 0);
11195 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11197 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11198 fold_convert_loc (loc, type, t2),
11199 fold_convert_loc (loc, type, t1));
11203 /* X ^ (X | Y) -> Y & ~ X*/
11204 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11205 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
11207 tree t2 = TREE_OPERAND (arg1, 1);
11208 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11210 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11211 fold_convert_loc (loc, type, t2),
11212 fold_convert_loc (loc, type, t1));
11216 /* X ^ (Y | X) -> Y & ~ X*/
11217 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11218 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
11220 tree t2 = TREE_OPERAND (arg1, 0);
11221 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11223 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11224 fold_convert_loc (loc, type, t2),
11225 fold_convert_loc (loc, type, t1));
11229 /* Convert ~X ^ ~Y to X ^ Y. */
11230 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11231 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11232 return fold_build2_loc (loc, code, type,
11233 fold_convert_loc (loc, type,
11234 TREE_OPERAND (arg0, 0)),
11235 fold_convert_loc (loc, type,
11236 TREE_OPERAND (arg1, 0)));
11238 /* Convert ~X ^ C to X ^ ~C. */
11239 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11240 && TREE_CODE (arg1) == INTEGER_CST)
11241 return fold_build2_loc (loc, code, type,
11242 fold_convert_loc (loc, type,
11243 TREE_OPERAND (arg0, 0)),
11244 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
11246 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
11247 if (TREE_CODE (arg0) == BIT_AND_EXPR
11248 && integer_onep (TREE_OPERAND (arg0, 1))
11249 && integer_onep (arg1))
11250 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
11251 build_int_cst (TREE_TYPE (arg0), 0));
11253 /* Fold (X & Y) ^ Y as ~X & Y. */
11254 if (TREE_CODE (arg0) == BIT_AND_EXPR
11255 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11257 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11258 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11259 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11260 fold_convert_loc (loc, type, arg1));
11262 /* Fold (X & Y) ^ X as ~Y & X. */
11263 if (TREE_CODE (arg0) == BIT_AND_EXPR
11264 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11265 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11267 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11268 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11269 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11270 fold_convert_loc (loc, type, arg1));
11272 /* Fold X ^ (X & Y) as X & ~Y. */
11273 if (TREE_CODE (arg1) == BIT_AND_EXPR
11274 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11276 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11277 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11278 fold_convert_loc (loc, type, arg0),
11279 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11281 /* Fold X ^ (Y & X) as ~Y & X. */
11282 if (TREE_CODE (arg1) == BIT_AND_EXPR
11283 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11284 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11286 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11287 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11288 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11289 fold_convert_loc (loc, type, arg0));
11292 /* See if this can be simplified into a rotate first. If that
11293 is unsuccessful continue in the association code. */
11297 if (integer_all_onesp (arg1))
11298 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11299 if (integer_zerop (arg1))
11300 return omit_one_operand_loc (loc, type, arg1, arg0);
11301 if (operand_equal_p (arg0, arg1, 0))
11302 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11304 /* ~X & X, (X == 0) & X, and !X & X are always zero. */
11305 if ((TREE_CODE (arg0) == BIT_NOT_EXPR
11306 || TREE_CODE (arg0) == TRUTH_NOT_EXPR
11307 || (TREE_CODE (arg0) == EQ_EXPR
11308 && integer_zerop (TREE_OPERAND (arg0, 1))))
11309 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11310 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11312 /* X & ~X , X & (X == 0), and X & !X are always zero. */
11313 if ((TREE_CODE (arg1) == BIT_NOT_EXPR
11314 || TREE_CODE (arg1) == TRUTH_NOT_EXPR
11315 || (TREE_CODE (arg1) == EQ_EXPR
11316 && integer_zerop (TREE_OPERAND (arg1, 1))))
11317 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11318 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11320 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
11321 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11322 && TREE_CODE (arg1) == INTEGER_CST
11323 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11325 tree tmp1 = fold_convert_loc (loc, type, arg1);
11326 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11327 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11328 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
11329 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
11331 fold_convert_loc (loc, type,
11332 fold_build2_loc (loc, BIT_IOR_EXPR,
11333 type, tmp2, tmp3));
11336 /* (X | Y) & Y is (X, Y). */
11337 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11338 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11339 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11340 /* (X | Y) & X is (Y, X). */
11341 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11342 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11343 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11344 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11345 /* X & (X | Y) is (Y, X). */
11346 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11347 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11348 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11349 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11350 /* X & (Y | X) is (Y, X). */
11351 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11352 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11353 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11354 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11356 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11357 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11358 && integer_onep (TREE_OPERAND (arg0, 1))
11359 && integer_onep (arg1))
11361 tem = TREE_OPERAND (arg0, 0);
11362 return fold_build2_loc (loc, EQ_EXPR, type,
11363 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11364 build_int_cst (TREE_TYPE (tem), 1)),
11365 build_int_cst (TREE_TYPE (tem), 0));
11367 /* Fold ~X & 1 as (X & 1) == 0. */
11368 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11369 && integer_onep (arg1))
11371 tem = TREE_OPERAND (arg0, 0);
11372 return fold_build2_loc (loc, EQ_EXPR, type,
11373 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11374 build_int_cst (TREE_TYPE (tem), 1)),
11375 build_int_cst (TREE_TYPE (tem), 0));
11377 /* Fold !X & 1 as X == 0. */
11378 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11379 && integer_onep (arg1))
11381 tem = TREE_OPERAND (arg0, 0);
11382 return fold_build2_loc (loc, EQ_EXPR, type, tem,
11383 build_int_cst (TREE_TYPE (tem), 0));
11386 /* Fold (X ^ Y) & Y as ~X & Y. */
11387 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11388 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11390 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11391 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11392 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11393 fold_convert_loc (loc, type, arg1));
11395 /* Fold (X ^ Y) & X as ~Y & X. */
11396 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11397 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11398 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11400 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11401 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11402 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11403 fold_convert_loc (loc, type, arg1));
11405 /* Fold X & (X ^ Y) as X & ~Y. */
11406 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11407 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11409 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11410 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11411 fold_convert_loc (loc, type, arg0),
11412 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11414 /* Fold X & (Y ^ X) as ~Y & X. */
11415 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11416 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11417 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11419 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11420 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11421 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11422 fold_convert_loc (loc, type, arg0));
11425 /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
11426 ((A & N) + B) & M -> (A + B) & M
11427 Similarly if (N & M) == 0,
11428 ((A | N) + B) & M -> (A + B) & M
11429 and for - instead of + (or unary - instead of +)
11430 and/or ^ instead of |.
11431 If B is constant and (B & M) == 0, fold into A & M. */
11432 if (host_integerp (arg1, 1))
11434 unsigned HOST_WIDE_INT cst1 = tree_low_cst (arg1, 1);
11435 if (~cst1 && (cst1 & (cst1 + 1)) == 0
11436 && INTEGRAL_TYPE_P (TREE_TYPE (arg0))
11437 && (TREE_CODE (arg0) == PLUS_EXPR
11438 || TREE_CODE (arg0) == MINUS_EXPR
11439 || TREE_CODE (arg0) == NEGATE_EXPR)
11440 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
11441 || TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE))
11445 unsigned HOST_WIDE_INT cst0;
11447 /* Now we know that arg0 is (C + D) or (C - D) or
11448 -C and arg1 (M) is == (1LL << cst) - 1.
11449 Store C into PMOP[0] and D into PMOP[1]. */
11450 pmop[0] = TREE_OPERAND (arg0, 0);
11452 if (TREE_CODE (arg0) != NEGATE_EXPR)
11454 pmop[1] = TREE_OPERAND (arg0, 1);
11458 if (!host_integerp (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11459 || (tree_low_cst (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11463 for (; which >= 0; which--)
11464 switch (TREE_CODE (pmop[which]))
11469 if (TREE_CODE (TREE_OPERAND (pmop[which], 1))
11472 /* tree_low_cst not used, because we don't care about
11474 cst0 = TREE_INT_CST_LOW (TREE_OPERAND (pmop[which], 1));
11476 if (TREE_CODE (pmop[which]) == BIT_AND_EXPR)
11481 else if (cst0 != 0)
11483 /* If C or D is of the form (A & N) where
11484 (N & M) == M, or of the form (A | N) or
11485 (A ^ N) where (N & M) == 0, replace it with A. */
11486 pmop[which] = TREE_OPERAND (pmop[which], 0);
11489 /* If C or D is a N where (N & M) == 0, it can be
11490 omitted (assumed 0). */
11491 if ((TREE_CODE (arg0) == PLUS_EXPR
11492 || (TREE_CODE (arg0) == MINUS_EXPR && which == 0))
11493 && (TREE_INT_CST_LOW (pmop[which]) & cst1) == 0)
11494 pmop[which] = NULL;
11500 /* Only build anything new if we optimized one or both arguments
11502 if (pmop[0] != TREE_OPERAND (arg0, 0)
11503 || (TREE_CODE (arg0) != NEGATE_EXPR
11504 && pmop[1] != TREE_OPERAND (arg0, 1)))
11506 tree utype = TREE_TYPE (arg0);
11507 if (! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
11509 /* Perform the operations in a type that has defined
11510 overflow behavior. */
11511 utype = unsigned_type_for (TREE_TYPE (arg0));
11512 if (pmop[0] != NULL)
11513 pmop[0] = fold_convert_loc (loc, utype, pmop[0]);
11514 if (pmop[1] != NULL)
11515 pmop[1] = fold_convert_loc (loc, utype, pmop[1]);
11518 if (TREE_CODE (arg0) == NEGATE_EXPR)
11519 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[0]);
11520 else if (TREE_CODE (arg0) == PLUS_EXPR)
11522 if (pmop[0] != NULL && pmop[1] != NULL)
11523 tem = fold_build2_loc (loc, PLUS_EXPR, utype,
11525 else if (pmop[0] != NULL)
11527 else if (pmop[1] != NULL)
11530 return build_int_cst (type, 0);
11532 else if (pmop[0] == NULL)
11533 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[1]);
11535 tem = fold_build2_loc (loc, MINUS_EXPR, utype,
11537 /* TEM is now the new binary +, - or unary - replacement. */
11538 tem = fold_build2_loc (loc, BIT_AND_EXPR, utype, tem,
11539 fold_convert_loc (loc, utype, arg1));
11540 return fold_convert_loc (loc, type, tem);
11545 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11546 if (t1 != NULL_TREE)
11548 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11549 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11550 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11553 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11555 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11556 && (~TREE_INT_CST_LOW (arg1)
11557 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11559 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11562 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11564 This results in more efficient code for machines without a NOR
11565 instruction. Combine will canonicalize to the first form
11566 which will allow use of NOR instructions provided by the
11567 backend if they exist. */
11568 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11569 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11571 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11572 build2 (BIT_IOR_EXPR, type,
11573 fold_convert_loc (loc, type,
11574 TREE_OPERAND (arg0, 0)),
11575 fold_convert_loc (loc, type,
11576 TREE_OPERAND (arg1, 0))));
11579 /* If arg0 is derived from the address of an object or function, we may
11580 be able to fold this expression using the object or function's
11582 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11584 unsigned HOST_WIDE_INT modulus, residue;
11585 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11587 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11588 integer_onep (arg1));
11590 /* This works because modulus is a power of 2. If this weren't the
11591 case, we'd have to replace it by its greatest power-of-2
11592 divisor: modulus & -modulus. */
11594 return build_int_cst (type, residue & low);
11597 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11598 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11599 if the new mask might be further optimized. */
11600 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11601 || TREE_CODE (arg0) == RSHIFT_EXPR)
11602 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11603 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11604 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11605 < TYPE_PRECISION (TREE_TYPE (arg0))
11606 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11607 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11609 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11610 unsigned HOST_WIDE_INT mask
11611 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11612 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11613 tree shift_type = TREE_TYPE (arg0);
11615 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11616 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11617 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11618 && TYPE_PRECISION (TREE_TYPE (arg0))
11619 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11621 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11622 tree arg00 = TREE_OPERAND (arg0, 0);
11623 /* See if more bits can be proven as zero because of
11625 if (TREE_CODE (arg00) == NOP_EXPR
11626 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11628 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11629 if (TYPE_PRECISION (inner_type)
11630 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11631 && TYPE_PRECISION (inner_type) < prec)
11633 prec = TYPE_PRECISION (inner_type);
11634 /* See if we can shorten the right shift. */
11636 shift_type = inner_type;
11639 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11640 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11641 zerobits <<= prec - shiftc;
11642 /* For arithmetic shift if sign bit could be set, zerobits
11643 can contain actually sign bits, so no transformation is
11644 possible, unless MASK masks them all away. In that
11645 case the shift needs to be converted into logical shift. */
11646 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11647 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11649 if ((mask & zerobits) == 0)
11650 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11656 /* ((X << 16) & 0xff00) is (X, 0). */
11657 if ((mask & zerobits) == mask)
11658 return omit_one_operand_loc (loc, type,
11659 build_int_cst (type, 0), arg0);
11661 newmask = mask | zerobits;
11662 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11666 /* Only do the transformation if NEWMASK is some integer
11668 for (prec = BITS_PER_UNIT;
11669 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11670 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11672 if (prec < HOST_BITS_PER_WIDE_INT
11673 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11677 if (shift_type != TREE_TYPE (arg0))
11679 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11680 fold_convert_loc (loc, shift_type,
11681 TREE_OPERAND (arg0, 0)),
11682 TREE_OPERAND (arg0, 1));
11683 tem = fold_convert_loc (loc, type, tem);
11687 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11688 if (!tree_int_cst_equal (newmaskt, arg1))
11689 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11697 /* Don't touch a floating-point divide by zero unless the mode
11698 of the constant can represent infinity. */
11699 if (TREE_CODE (arg1) == REAL_CST
11700 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11701 && real_zerop (arg1))
11704 /* Optimize A / A to 1.0 if we don't care about
11705 NaNs or Infinities. Skip the transformation
11706 for non-real operands. */
11707 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11708 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11709 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11710 && operand_equal_p (arg0, arg1, 0))
11712 tree r = build_real (TREE_TYPE (arg0), dconst1);
11714 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11717 /* The complex version of the above A / A optimization. */
11718 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11719 && operand_equal_p (arg0, arg1, 0))
11721 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11722 if (! HONOR_NANS (TYPE_MODE (elem_type))
11723 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11725 tree r = build_real (elem_type, dconst1);
11726 /* omit_two_operands will call fold_convert for us. */
11727 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11731 /* (-A) / (-B) -> A / B */
11732 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11733 return fold_build2_loc (loc, RDIV_EXPR, type,
11734 TREE_OPERAND (arg0, 0),
11735 negate_expr (arg1));
11736 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11737 return fold_build2_loc (loc, RDIV_EXPR, type,
11738 negate_expr (arg0),
11739 TREE_OPERAND (arg1, 0));
11741 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11742 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11743 && real_onep (arg1))
11744 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11746 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11747 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11748 && real_minus_onep (arg1))
11749 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11750 negate_expr (arg0)));
11752 /* If ARG1 is a constant, we can convert this to a multiply by the
11753 reciprocal. This does not have the same rounding properties,
11754 so only do this if -freciprocal-math. We can actually
11755 always safely do it if ARG1 is a power of two, but it's hard to
11756 tell if it is or not in a portable manner. */
11757 if (TREE_CODE (arg1) == REAL_CST)
11759 if (flag_reciprocal_math
11760 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11762 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11763 /* Find the reciprocal if optimizing and the result is exact. */
11767 r = TREE_REAL_CST (arg1);
11768 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11770 tem = build_real (type, r);
11771 return fold_build2_loc (loc, MULT_EXPR, type,
11772 fold_convert_loc (loc, type, arg0), tem);
11776 /* Convert A/B/C to A/(B*C). */
11777 if (flag_reciprocal_math
11778 && TREE_CODE (arg0) == RDIV_EXPR)
11779 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11780 fold_build2_loc (loc, MULT_EXPR, type,
11781 TREE_OPERAND (arg0, 1), arg1));
11783 /* Convert A/(B/C) to (A/B)*C. */
11784 if (flag_reciprocal_math
11785 && TREE_CODE (arg1) == RDIV_EXPR)
11786 return fold_build2_loc (loc, MULT_EXPR, type,
11787 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11788 TREE_OPERAND (arg1, 0)),
11789 TREE_OPERAND (arg1, 1));
11791 /* Convert C1/(X*C2) into (C1/C2)/X. */
11792 if (flag_reciprocal_math
11793 && TREE_CODE (arg1) == MULT_EXPR
11794 && TREE_CODE (arg0) == REAL_CST
11795 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11797 tree tem = const_binop (RDIV_EXPR, arg0,
11798 TREE_OPERAND (arg1, 1));
11800 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11801 TREE_OPERAND (arg1, 0));
11804 if (flag_unsafe_math_optimizations)
11806 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11807 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11809 /* Optimize sin(x)/cos(x) as tan(x). */
11810 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11811 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11812 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11813 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11814 CALL_EXPR_ARG (arg1, 0), 0))
11816 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11818 if (tanfn != NULL_TREE)
11819 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11822 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11823 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11824 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11825 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11826 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11827 CALL_EXPR_ARG (arg1, 0), 0))
11829 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11831 if (tanfn != NULL_TREE)
11833 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11834 CALL_EXPR_ARG (arg0, 0));
11835 return fold_build2_loc (loc, RDIV_EXPR, type,
11836 build_real (type, dconst1), tmp);
11840 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11841 NaNs or Infinities. */
11842 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11843 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11844 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11846 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11847 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11849 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11850 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11851 && operand_equal_p (arg00, arg01, 0))
11853 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11855 if (cosfn != NULL_TREE)
11856 return build_call_expr_loc (loc, cosfn, 1, arg00);
11860 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11861 NaNs or Infinities. */
11862 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11863 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11864 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11866 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11867 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11869 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11870 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11871 && operand_equal_p (arg00, arg01, 0))
11873 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11875 if (cosfn != NULL_TREE)
11877 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11878 return fold_build2_loc (loc, RDIV_EXPR, type,
11879 build_real (type, dconst1),
11885 /* Optimize pow(x,c)/x as pow(x,c-1). */
11886 if (fcode0 == BUILT_IN_POW
11887 || fcode0 == BUILT_IN_POWF
11888 || fcode0 == BUILT_IN_POWL)
11890 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11891 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11892 if (TREE_CODE (arg01) == REAL_CST
11893 && !TREE_OVERFLOW (arg01)
11894 && operand_equal_p (arg1, arg00, 0))
11896 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11900 c = TREE_REAL_CST (arg01);
11901 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11902 arg = build_real (type, c);
11903 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11907 /* Optimize a/root(b/c) into a*root(c/b). */
11908 if (BUILTIN_ROOT_P (fcode1))
11910 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11912 if (TREE_CODE (rootarg) == RDIV_EXPR)
11914 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11915 tree b = TREE_OPERAND (rootarg, 0);
11916 tree c = TREE_OPERAND (rootarg, 1);
11918 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
11920 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
11921 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
11925 /* Optimize x/expN(y) into x*expN(-y). */
11926 if (BUILTIN_EXPONENT_P (fcode1))
11928 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11929 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11930 arg1 = build_call_expr_loc (loc,
11932 fold_convert_loc (loc, type, arg));
11933 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11936 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11937 if (fcode1 == BUILT_IN_POW
11938 || fcode1 == BUILT_IN_POWF
11939 || fcode1 == BUILT_IN_POWL)
11941 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11942 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11943 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11944 tree neg11 = fold_convert_loc (loc, type,
11945 negate_expr (arg11));
11946 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
11947 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11952 case TRUNC_DIV_EXPR:
11953 /* Optimize (X & (-A)) / A where A is a power of 2,
11955 if (TREE_CODE (arg0) == BIT_AND_EXPR
11956 && !TYPE_UNSIGNED (type) && TREE_CODE (arg1) == INTEGER_CST
11957 && integer_pow2p (arg1) && tree_int_cst_sgn (arg1) > 0)
11959 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (arg1),
11960 arg1, TREE_OPERAND (arg0, 1));
11961 if (sum && integer_zerop (sum)) {
11962 unsigned long pow2;
11964 if (TREE_INT_CST_LOW (arg1))
11965 pow2 = exact_log2 (TREE_INT_CST_LOW (arg1));
11967 pow2 = exact_log2 (TREE_INT_CST_HIGH (arg1))
11968 + HOST_BITS_PER_WIDE_INT;
11970 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11971 TREE_OPERAND (arg0, 0),
11972 build_int_cst (integer_type_node, pow2));
11978 case FLOOR_DIV_EXPR:
11979 /* Simplify A / (B << N) where A and B are positive and B is
11980 a power of 2, to A >> (N + log2(B)). */
11981 strict_overflow_p = false;
11982 if (TREE_CODE (arg1) == LSHIFT_EXPR
11983 && (TYPE_UNSIGNED (type)
11984 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11986 tree sval = TREE_OPERAND (arg1, 0);
11987 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11989 tree sh_cnt = TREE_OPERAND (arg1, 1);
11990 unsigned long pow2;
11992 if (TREE_INT_CST_LOW (sval))
11993 pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11995 pow2 = exact_log2 (TREE_INT_CST_HIGH (sval))
11996 + HOST_BITS_PER_WIDE_INT;
11998 if (strict_overflow_p)
11999 fold_overflow_warning (("assuming signed overflow does not "
12000 "occur when simplifying A / (B << N)"),
12001 WARN_STRICT_OVERFLOW_MISC);
12003 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
12005 build_int_cst (TREE_TYPE (sh_cnt),
12007 return fold_build2_loc (loc, RSHIFT_EXPR, type,
12008 fold_convert_loc (loc, type, arg0), sh_cnt);
12012 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
12013 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
12014 if (INTEGRAL_TYPE_P (type)
12015 && TYPE_UNSIGNED (type)
12016 && code == FLOOR_DIV_EXPR)
12017 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
12021 case ROUND_DIV_EXPR:
12022 case CEIL_DIV_EXPR:
12023 case EXACT_DIV_EXPR:
12024 if (integer_onep (arg1))
12025 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12026 if (integer_zerop (arg1))
12028 /* X / -1 is -X. */
12029 if (!TYPE_UNSIGNED (type)
12030 && TREE_CODE (arg1) == INTEGER_CST
12031 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12032 && TREE_INT_CST_HIGH (arg1) == -1)
12033 return fold_convert_loc (loc, type, negate_expr (arg0));
12035 /* Convert -A / -B to A / B when the type is signed and overflow is
12037 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12038 && TREE_CODE (arg0) == NEGATE_EXPR
12039 && negate_expr_p (arg1))
12041 if (INTEGRAL_TYPE_P (type))
12042 fold_overflow_warning (("assuming signed overflow does not occur "
12043 "when distributing negation across "
12045 WARN_STRICT_OVERFLOW_MISC);
12046 return fold_build2_loc (loc, code, type,
12047 fold_convert_loc (loc, type,
12048 TREE_OPERAND (arg0, 0)),
12049 fold_convert_loc (loc, type,
12050 negate_expr (arg1)));
12052 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12053 && TREE_CODE (arg1) == NEGATE_EXPR
12054 && negate_expr_p (arg0))
12056 if (INTEGRAL_TYPE_P (type))
12057 fold_overflow_warning (("assuming signed overflow does not occur "
12058 "when distributing negation across "
12060 WARN_STRICT_OVERFLOW_MISC);
12061 return fold_build2_loc (loc, code, type,
12062 fold_convert_loc (loc, type,
12063 negate_expr (arg0)),
12064 fold_convert_loc (loc, type,
12065 TREE_OPERAND (arg1, 0)));
12068 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
12069 operation, EXACT_DIV_EXPR.
12071 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
12072 At one time others generated faster code, it's not clear if they do
12073 after the last round to changes to the DIV code in expmed.c. */
12074 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
12075 && multiple_of_p (type, arg0, arg1))
12076 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
12078 strict_overflow_p = false;
12079 if (TREE_CODE (arg1) == INTEGER_CST
12080 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12081 &strict_overflow_p)))
12083 if (strict_overflow_p)
12084 fold_overflow_warning (("assuming signed overflow does not occur "
12085 "when simplifying division"),
12086 WARN_STRICT_OVERFLOW_MISC);
12087 return fold_convert_loc (loc, type, tem);
12092 case CEIL_MOD_EXPR:
12093 case FLOOR_MOD_EXPR:
12094 case ROUND_MOD_EXPR:
12095 case TRUNC_MOD_EXPR:
12096 /* X % 1 is always zero, but be sure to preserve any side
12098 if (integer_onep (arg1))
12099 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12101 /* X % 0, return X % 0 unchanged so that we can get the
12102 proper warnings and errors. */
12103 if (integer_zerop (arg1))
12106 /* 0 % X is always zero, but be sure to preserve any side
12107 effects in X. Place this after checking for X == 0. */
12108 if (integer_zerop (arg0))
12109 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12111 /* X % -1 is zero. */
12112 if (!TYPE_UNSIGNED (type)
12113 && TREE_CODE (arg1) == INTEGER_CST
12114 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12115 && TREE_INT_CST_HIGH (arg1) == -1)
12116 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12118 /* X % -C is the same as X % C. */
12119 if (code == TRUNC_MOD_EXPR
12120 && !TYPE_UNSIGNED (type)
12121 && TREE_CODE (arg1) == INTEGER_CST
12122 && !TREE_OVERFLOW (arg1)
12123 && TREE_INT_CST_HIGH (arg1) < 0
12124 && !TYPE_OVERFLOW_TRAPS (type)
12125 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
12126 && !sign_bit_p (arg1, arg1))
12127 return fold_build2_loc (loc, code, type,
12128 fold_convert_loc (loc, type, arg0),
12129 fold_convert_loc (loc, type,
12130 negate_expr (arg1)));
12132 /* X % -Y is the same as X % Y. */
12133 if (code == TRUNC_MOD_EXPR
12134 && !TYPE_UNSIGNED (type)
12135 && TREE_CODE (arg1) == NEGATE_EXPR
12136 && !TYPE_OVERFLOW_TRAPS (type))
12137 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
12138 fold_convert_loc (loc, type,
12139 TREE_OPERAND (arg1, 0)));
12141 strict_overflow_p = false;
12142 if (TREE_CODE (arg1) == INTEGER_CST
12143 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12144 &strict_overflow_p)))
12146 if (strict_overflow_p)
12147 fold_overflow_warning (("assuming signed overflow does not occur "
12148 "when simplifying modulus"),
12149 WARN_STRICT_OVERFLOW_MISC);
12150 return fold_convert_loc (loc, type, tem);
12153 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
12154 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
12155 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
12156 && (TYPE_UNSIGNED (type)
12157 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
12160 /* Also optimize A % (C << N) where C is a power of 2,
12161 to A & ((C << N) - 1). */
12162 if (TREE_CODE (arg1) == LSHIFT_EXPR)
12163 c = TREE_OPERAND (arg1, 0);
12165 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
12168 = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
12169 build_int_cst (TREE_TYPE (arg1), 1));
12170 if (strict_overflow_p)
12171 fold_overflow_warning (("assuming signed overflow does not "
12172 "occur when simplifying "
12173 "X % (power of two)"),
12174 WARN_STRICT_OVERFLOW_MISC);
12175 return fold_build2_loc (loc, BIT_AND_EXPR, type,
12176 fold_convert_loc (loc, type, arg0),
12177 fold_convert_loc (loc, type, mask));
12185 if (integer_all_onesp (arg0))
12186 return omit_one_operand_loc (loc, type, arg0, arg1);
12190 /* Optimize -1 >> x for arithmetic right shifts. */
12191 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
12192 && tree_expr_nonnegative_p (arg1))
12193 return omit_one_operand_loc (loc, type, arg0, arg1);
12194 /* ... fall through ... */
12198 if (integer_zerop (arg1))
12199 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12200 if (integer_zerop (arg0))
12201 return omit_one_operand_loc (loc, type, arg0, arg1);
12203 /* Since negative shift count is not well-defined,
12204 don't try to compute it in the compiler. */
12205 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
12208 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
12209 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
12210 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12211 && host_integerp (TREE_OPERAND (arg0, 1), false)
12212 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12214 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
12215 + TREE_INT_CST_LOW (arg1));
12217 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
12218 being well defined. */
12219 if (low >= TYPE_PRECISION (type))
12221 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
12222 low = low % TYPE_PRECISION (type);
12223 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
12224 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
12225 TREE_OPERAND (arg0, 0));
12227 low = TYPE_PRECISION (type) - 1;
12230 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12231 build_int_cst (type, low));
12234 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
12235 into x & ((unsigned)-1 >> c) for unsigned types. */
12236 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
12237 || (TYPE_UNSIGNED (type)
12238 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
12239 && host_integerp (arg1, false)
12240 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12241 && host_integerp (TREE_OPERAND (arg0, 1), false)
12242 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12244 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
12245 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
12251 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12253 lshift = build_int_cst (type, -1);
12254 lshift = int_const_binop (code, lshift, arg1);
12256 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
12260 /* Rewrite an LROTATE_EXPR by a constant into an
12261 RROTATE_EXPR by a new constant. */
12262 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
12264 tree tem = build_int_cst (TREE_TYPE (arg1),
12265 TYPE_PRECISION (type));
12266 tem = const_binop (MINUS_EXPR, tem, arg1);
12267 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
12270 /* If we have a rotate of a bit operation with the rotate count and
12271 the second operand of the bit operation both constant,
12272 permute the two operations. */
12273 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12274 && (TREE_CODE (arg0) == BIT_AND_EXPR
12275 || TREE_CODE (arg0) == BIT_IOR_EXPR
12276 || TREE_CODE (arg0) == BIT_XOR_EXPR)
12277 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12278 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12279 fold_build2_loc (loc, code, type,
12280 TREE_OPERAND (arg0, 0), arg1),
12281 fold_build2_loc (loc, code, type,
12282 TREE_OPERAND (arg0, 1), arg1));
12284 /* Two consecutive rotates adding up to the precision of the
12285 type can be ignored. */
12286 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12287 && TREE_CODE (arg0) == RROTATE_EXPR
12288 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12289 && TREE_INT_CST_HIGH (arg1) == 0
12290 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
12291 && ((TREE_INT_CST_LOW (arg1)
12292 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
12293 == (unsigned int) TYPE_PRECISION (type)))
12294 return TREE_OPERAND (arg0, 0);
12296 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
12297 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
12298 if the latter can be further optimized. */
12299 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
12300 && TREE_CODE (arg0) == BIT_AND_EXPR
12301 && TREE_CODE (arg1) == INTEGER_CST
12302 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12304 tree mask = fold_build2_loc (loc, code, type,
12305 fold_convert_loc (loc, type,
12306 TREE_OPERAND (arg0, 1)),
12308 tree shift = fold_build2_loc (loc, code, type,
12309 fold_convert_loc (loc, type,
12310 TREE_OPERAND (arg0, 0)),
12312 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
12320 if (operand_equal_p (arg0, arg1, 0))
12321 return omit_one_operand_loc (loc, type, arg0, arg1);
12322 if (INTEGRAL_TYPE_P (type)
12323 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
12324 return omit_one_operand_loc (loc, type, arg1, arg0);
12325 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
12331 if (operand_equal_p (arg0, arg1, 0))
12332 return omit_one_operand_loc (loc, type, arg0, arg1);
12333 if (INTEGRAL_TYPE_P (type)
12334 && TYPE_MAX_VALUE (type)
12335 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
12336 return omit_one_operand_loc (loc, type, arg1, arg0);
12337 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
12342 case TRUTH_ANDIF_EXPR:
12343 /* Note that the operands of this must be ints
12344 and their values must be 0 or 1.
12345 ("true" is a fixed value perhaps depending on the language.) */
12346 /* If first arg is constant zero, return it. */
12347 if (integer_zerop (arg0))
12348 return fold_convert_loc (loc, type, arg0);
12349 case TRUTH_AND_EXPR:
12350 /* If either arg is constant true, drop it. */
12351 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12352 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12353 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
12354 /* Preserve sequence points. */
12355 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12356 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12357 /* If second arg is constant zero, result is zero, but first arg
12358 must be evaluated. */
12359 if (integer_zerop (arg1))
12360 return omit_one_operand_loc (loc, type, arg1, arg0);
12361 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
12362 case will be handled here. */
12363 if (integer_zerop (arg0))
12364 return omit_one_operand_loc (loc, type, arg0, arg1);
12366 /* !X && X is always false. */
12367 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12368 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12369 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12370 /* X && !X is always false. */
12371 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12372 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12373 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12375 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12376 means A >= Y && A != MAX, but in this case we know that
12379 if (!TREE_SIDE_EFFECTS (arg0)
12380 && !TREE_SIDE_EFFECTS (arg1))
12382 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
12383 if (tem && !operand_equal_p (tem, arg0, 0))
12384 return fold_build2_loc (loc, code, type, tem, arg1);
12386 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12387 if (tem && !operand_equal_p (tem, arg1, 0))
12388 return fold_build2_loc (loc, code, type, arg0, tem);
12391 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12397 case TRUTH_ORIF_EXPR:
12398 /* Note that the operands of this must be ints
12399 and their values must be 0 or true.
12400 ("true" is a fixed value perhaps depending on the language.) */
12401 /* If first arg is constant true, return it. */
12402 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12403 return fold_convert_loc (loc, type, arg0);
12404 case TRUTH_OR_EXPR:
12405 /* If either arg is constant zero, drop it. */
12406 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12407 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12408 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12409 /* Preserve sequence points. */
12410 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12411 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12412 /* If second arg is constant true, result is true, but we must
12413 evaluate first arg. */
12414 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12415 return omit_one_operand_loc (loc, type, arg1, arg0);
12416 /* Likewise for first arg, but note this only occurs here for
12418 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12419 return omit_one_operand_loc (loc, type, arg0, arg1);
12421 /* !X || X is always true. */
12422 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12423 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12424 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12425 /* X || !X is always true. */
12426 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12427 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12428 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12430 /* (X && !Y) || (!X && Y) is X ^ Y */
12431 if (TREE_CODE (arg0) == TRUTH_AND_EXPR
12432 && TREE_CODE (arg1) == TRUTH_AND_EXPR)
12434 tree a0, a1, l0, l1, n0, n1;
12436 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
12437 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
12439 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12440 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
12442 n0 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l0);
12443 n1 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l1);
12445 if ((operand_equal_p (n0, a0, 0)
12446 && operand_equal_p (n1, a1, 0))
12447 || (operand_equal_p (n0, a1, 0)
12448 && operand_equal_p (n1, a0, 0)))
12449 return fold_build2_loc (loc, TRUTH_XOR_EXPR, type, l0, n1);
12452 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12458 case TRUTH_XOR_EXPR:
12459 /* If the second arg is constant zero, drop it. */
12460 if (integer_zerop (arg1))
12461 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12462 /* If the second arg is constant true, this is a logical inversion. */
12463 if (integer_onep (arg1))
12465 /* Only call invert_truthvalue if operand is a truth value. */
12466 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12467 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12469 tem = invert_truthvalue_loc (loc, arg0);
12470 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12472 /* Identical arguments cancel to zero. */
12473 if (operand_equal_p (arg0, arg1, 0))
12474 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12476 /* !X ^ X is always true. */
12477 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12478 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12479 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12481 /* X ^ !X is always true. */
12482 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12483 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12484 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12493 tem = fold_comparison (loc, code, type, op0, op1);
12494 if (tem != NULL_TREE)
12497 /* bool_var != 0 becomes bool_var. */
12498 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12499 && code == NE_EXPR)
12500 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12502 /* bool_var == 1 becomes bool_var. */
12503 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12504 && code == EQ_EXPR)
12505 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12507 /* bool_var != 1 becomes !bool_var. */
12508 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12509 && code == NE_EXPR)
12510 return fold_convert_loc (loc, type,
12511 fold_build1_loc (loc, TRUTH_NOT_EXPR,
12512 TREE_TYPE (arg0), arg0));
12514 /* bool_var == 0 becomes !bool_var. */
12515 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12516 && code == EQ_EXPR)
12517 return fold_convert_loc (loc, type,
12518 fold_build1_loc (loc, TRUTH_NOT_EXPR,
12519 TREE_TYPE (arg0), arg0));
12521 /* !exp != 0 becomes !exp */
12522 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12523 && code == NE_EXPR)
12524 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12526 /* If this is an equality comparison of the address of two non-weak,
12527 unaliased symbols neither of which are extern (since we do not
12528 have access to attributes for externs), then we know the result. */
12529 if (TREE_CODE (arg0) == ADDR_EXPR
12530 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12531 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12532 && ! lookup_attribute ("alias",
12533 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12534 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12535 && TREE_CODE (arg1) == ADDR_EXPR
12536 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12537 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12538 && ! lookup_attribute ("alias",
12539 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12540 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12542 /* We know that we're looking at the address of two
12543 non-weak, unaliased, static _DECL nodes.
12545 It is both wasteful and incorrect to call operand_equal_p
12546 to compare the two ADDR_EXPR nodes. It is wasteful in that
12547 all we need to do is test pointer equality for the arguments
12548 to the two ADDR_EXPR nodes. It is incorrect to use
12549 operand_equal_p as that function is NOT equivalent to a
12550 C equality test. It can in fact return false for two
12551 objects which would test as equal using the C equality
12553 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12554 return constant_boolean_node (equal
12555 ? code == EQ_EXPR : code != EQ_EXPR,
12559 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12560 a MINUS_EXPR of a constant, we can convert it into a comparison with
12561 a revised constant as long as no overflow occurs. */
12562 if (TREE_CODE (arg1) == INTEGER_CST
12563 && (TREE_CODE (arg0) == PLUS_EXPR
12564 || TREE_CODE (arg0) == MINUS_EXPR)
12565 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12566 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12567 ? MINUS_EXPR : PLUS_EXPR,
12568 fold_convert_loc (loc, TREE_TYPE (arg0),
12570 TREE_OPERAND (arg0, 1)))
12571 && !TREE_OVERFLOW (tem))
12572 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12574 /* Similarly for a NEGATE_EXPR. */
12575 if (TREE_CODE (arg0) == NEGATE_EXPR
12576 && TREE_CODE (arg1) == INTEGER_CST
12577 && 0 != (tem = negate_expr (fold_convert_loc (loc, TREE_TYPE (arg0),
12579 && TREE_CODE (tem) == INTEGER_CST
12580 && !TREE_OVERFLOW (tem))
12581 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12583 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12584 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12585 && TREE_CODE (arg1) == INTEGER_CST
12586 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12587 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12588 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12589 fold_convert_loc (loc,
12592 TREE_OPERAND (arg0, 1)));
12594 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12595 if ((TREE_CODE (arg0) == PLUS_EXPR
12596 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12597 || TREE_CODE (arg0) == MINUS_EXPR)
12598 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12601 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12602 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12604 tree val = TREE_OPERAND (arg0, 1);
12605 return omit_two_operands_loc (loc, type,
12606 fold_build2_loc (loc, code, type,
12608 build_int_cst (TREE_TYPE (val),
12610 TREE_OPERAND (arg0, 0), arg1);
12613 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12614 if (TREE_CODE (arg0) == MINUS_EXPR
12615 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12616 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12619 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12621 return omit_two_operands_loc (loc, type,
12623 ? boolean_true_node : boolean_false_node,
12624 TREE_OPERAND (arg0, 1), arg1);
12627 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12628 for !=. Don't do this for ordered comparisons due to overflow. */
12629 if (TREE_CODE (arg0) == MINUS_EXPR
12630 && integer_zerop (arg1))
12631 return fold_build2_loc (loc, code, type,
12632 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12634 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12635 if (TREE_CODE (arg0) == ABS_EXPR
12636 && (integer_zerop (arg1) || real_zerop (arg1)))
12637 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12639 /* If this is an EQ or NE comparison with zero and ARG0 is
12640 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12641 two operations, but the latter can be done in one less insn
12642 on machines that have only two-operand insns or on which a
12643 constant cannot be the first operand. */
12644 if (TREE_CODE (arg0) == BIT_AND_EXPR
12645 && integer_zerop (arg1))
12647 tree arg00 = TREE_OPERAND (arg0, 0);
12648 tree arg01 = TREE_OPERAND (arg0, 1);
12649 if (TREE_CODE (arg00) == LSHIFT_EXPR
12650 && integer_onep (TREE_OPERAND (arg00, 0)))
12652 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12653 arg01, TREE_OPERAND (arg00, 1));
12654 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12655 build_int_cst (TREE_TYPE (arg0), 1));
12656 return fold_build2_loc (loc, code, type,
12657 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12660 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12661 && integer_onep (TREE_OPERAND (arg01, 0)))
12663 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12664 arg00, TREE_OPERAND (arg01, 1));
12665 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12666 build_int_cst (TREE_TYPE (arg0), 1));
12667 return fold_build2_loc (loc, code, type,
12668 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12673 /* If this is an NE or EQ comparison of zero against the result of a
12674 signed MOD operation whose second operand is a power of 2, make
12675 the MOD operation unsigned since it is simpler and equivalent. */
12676 if (integer_zerop (arg1)
12677 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12678 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12679 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12680 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12681 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12682 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12684 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12685 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12686 fold_convert_loc (loc, newtype,
12687 TREE_OPERAND (arg0, 0)),
12688 fold_convert_loc (loc, newtype,
12689 TREE_OPERAND (arg0, 1)));
12691 return fold_build2_loc (loc, code, type, newmod,
12692 fold_convert_loc (loc, newtype, arg1));
12695 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12696 C1 is a valid shift constant, and C2 is a power of two, i.e.
12698 if (TREE_CODE (arg0) == BIT_AND_EXPR
12699 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12700 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12702 && integer_pow2p (TREE_OPERAND (arg0, 1))
12703 && integer_zerop (arg1))
12705 tree itype = TREE_TYPE (arg0);
12706 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12707 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12709 /* Check for a valid shift count. */
12710 if (TREE_INT_CST_HIGH (arg001) == 0
12711 && TREE_INT_CST_LOW (arg001) < prec)
12713 tree arg01 = TREE_OPERAND (arg0, 1);
12714 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12715 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12716 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12717 can be rewritten as (X & (C2 << C1)) != 0. */
12718 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12720 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12721 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12722 return fold_build2_loc (loc, code, type, tem,
12723 fold_convert_loc (loc, itype, arg1));
12725 /* Otherwise, for signed (arithmetic) shifts,
12726 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12727 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12728 else if (!TYPE_UNSIGNED (itype))
12729 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12730 arg000, build_int_cst (itype, 0));
12731 /* Otherwise, of unsigned (logical) shifts,
12732 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12733 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12735 return omit_one_operand_loc (loc, type,
12736 code == EQ_EXPR ? integer_one_node
12737 : integer_zero_node,
12742 /* If we have (A & C) == C where C is a power of 2, convert this into
12743 (A & C) != 0. Similarly for NE_EXPR. */
12744 if (TREE_CODE (arg0) == BIT_AND_EXPR
12745 && integer_pow2p (TREE_OPERAND (arg0, 1))
12746 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12747 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12748 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12749 integer_zero_node));
12751 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12752 bit, then fold the expression into A < 0 or A >= 0. */
12753 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12757 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12758 Similarly for NE_EXPR. */
12759 if (TREE_CODE (arg0) == BIT_AND_EXPR
12760 && TREE_CODE (arg1) == INTEGER_CST
12761 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12763 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12764 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12765 TREE_OPERAND (arg0, 1));
12767 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12768 fold_convert_loc (loc, TREE_TYPE (arg0), arg1),
12770 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12771 if (integer_nonzerop (dandnotc))
12772 return omit_one_operand_loc (loc, type, rslt, arg0);
12775 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12776 Similarly for NE_EXPR. */
12777 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12778 && TREE_CODE (arg1) == INTEGER_CST
12779 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12781 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12783 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12784 TREE_OPERAND (arg0, 1),
12785 fold_convert_loc (loc, TREE_TYPE (arg0), notd));
12786 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12787 if (integer_nonzerop (candnotd))
12788 return omit_one_operand_loc (loc, type, rslt, arg0);
12791 /* If this is a comparison of a field, we may be able to simplify it. */
12792 if ((TREE_CODE (arg0) == COMPONENT_REF
12793 || TREE_CODE (arg0) == BIT_FIELD_REF)
12794 /* Handle the constant case even without -O
12795 to make sure the warnings are given. */
12796 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12798 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12803 /* Optimize comparisons of strlen vs zero to a compare of the
12804 first character of the string vs zero. To wit,
12805 strlen(ptr) == 0 => *ptr == 0
12806 strlen(ptr) != 0 => *ptr != 0
12807 Other cases should reduce to one of these two (or a constant)
12808 due to the return value of strlen being unsigned. */
12809 if (TREE_CODE (arg0) == CALL_EXPR
12810 && integer_zerop (arg1))
12812 tree fndecl = get_callee_fndecl (arg0);
12815 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12816 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12817 && call_expr_nargs (arg0) == 1
12818 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12820 tree iref = build_fold_indirect_ref_loc (loc,
12821 CALL_EXPR_ARG (arg0, 0));
12822 return fold_build2_loc (loc, code, type, iref,
12823 build_int_cst (TREE_TYPE (iref), 0));
12827 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12828 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12829 if (TREE_CODE (arg0) == RSHIFT_EXPR
12830 && integer_zerop (arg1)
12831 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12833 tree arg00 = TREE_OPERAND (arg0, 0);
12834 tree arg01 = TREE_OPERAND (arg0, 1);
12835 tree itype = TREE_TYPE (arg00);
12836 if (TREE_INT_CST_HIGH (arg01) == 0
12837 && TREE_INT_CST_LOW (arg01)
12838 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12840 if (TYPE_UNSIGNED (itype))
12842 itype = signed_type_for (itype);
12843 arg00 = fold_convert_loc (loc, itype, arg00);
12845 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12846 type, arg00, build_int_cst (itype, 0));
12850 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12851 if (integer_zerop (arg1)
12852 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12853 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12854 TREE_OPERAND (arg0, 1));
12856 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12857 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12858 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12859 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12860 build_zero_cst (TREE_TYPE (arg0)));
12861 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12862 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12863 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12864 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12865 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12866 build_zero_cst (TREE_TYPE (arg0)));
12868 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12869 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12870 && TREE_CODE (arg1) == INTEGER_CST
12871 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12872 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12873 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12874 TREE_OPERAND (arg0, 1), arg1));
12876 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12877 (X & C) == 0 when C is a single bit. */
12878 if (TREE_CODE (arg0) == BIT_AND_EXPR
12879 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12880 && integer_zerop (arg1)
12881 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12883 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12884 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12885 TREE_OPERAND (arg0, 1));
12886 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12888 fold_convert_loc (loc, TREE_TYPE (arg0),
12892 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12893 constant C is a power of two, i.e. a single bit. */
12894 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12895 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12896 && integer_zerop (arg1)
12897 && integer_pow2p (TREE_OPERAND (arg0, 1))
12898 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12899 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12901 tree arg00 = TREE_OPERAND (arg0, 0);
12902 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12903 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12906 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12907 when is C is a power of two, i.e. a single bit. */
12908 if (TREE_CODE (arg0) == BIT_AND_EXPR
12909 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12910 && integer_zerop (arg1)
12911 && integer_pow2p (TREE_OPERAND (arg0, 1))
12912 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12913 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12915 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12916 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
12917 arg000, TREE_OPERAND (arg0, 1));
12918 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12919 tem, build_int_cst (TREE_TYPE (tem), 0));
12922 if (integer_zerop (arg1)
12923 && tree_expr_nonzero_p (arg0))
12925 tree res = constant_boolean_node (code==NE_EXPR, type);
12926 return omit_one_operand_loc (loc, type, res, arg0);
12929 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12930 if (TREE_CODE (arg0) == NEGATE_EXPR
12931 && TREE_CODE (arg1) == NEGATE_EXPR)
12932 return fold_build2_loc (loc, code, type,
12933 TREE_OPERAND (arg0, 0),
12934 fold_convert_loc (loc, TREE_TYPE (arg0),
12935 TREE_OPERAND (arg1, 0)));
12937 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12938 if (TREE_CODE (arg0) == BIT_AND_EXPR
12939 && TREE_CODE (arg1) == BIT_AND_EXPR)
12941 tree arg00 = TREE_OPERAND (arg0, 0);
12942 tree arg01 = TREE_OPERAND (arg0, 1);
12943 tree arg10 = TREE_OPERAND (arg1, 0);
12944 tree arg11 = TREE_OPERAND (arg1, 1);
12945 tree itype = TREE_TYPE (arg0);
12947 if (operand_equal_p (arg01, arg11, 0))
12948 return fold_build2_loc (loc, code, type,
12949 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12950 fold_build2_loc (loc,
12951 BIT_XOR_EXPR, itype,
12954 build_zero_cst (itype));
12956 if (operand_equal_p (arg01, arg10, 0))
12957 return fold_build2_loc (loc, code, type,
12958 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12959 fold_build2_loc (loc,
12960 BIT_XOR_EXPR, itype,
12963 build_zero_cst (itype));
12965 if (operand_equal_p (arg00, arg11, 0))
12966 return fold_build2_loc (loc, code, type,
12967 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12968 fold_build2_loc (loc,
12969 BIT_XOR_EXPR, itype,
12972 build_zero_cst (itype));
12974 if (operand_equal_p (arg00, arg10, 0))
12975 return fold_build2_loc (loc, code, type,
12976 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12977 fold_build2_loc (loc,
12978 BIT_XOR_EXPR, itype,
12981 build_zero_cst (itype));
12984 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12985 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12987 tree arg00 = TREE_OPERAND (arg0, 0);
12988 tree arg01 = TREE_OPERAND (arg0, 1);
12989 tree arg10 = TREE_OPERAND (arg1, 0);
12990 tree arg11 = TREE_OPERAND (arg1, 1);
12991 tree itype = TREE_TYPE (arg0);
12993 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12994 operand_equal_p guarantees no side-effects so we don't need
12995 to use omit_one_operand on Z. */
12996 if (operand_equal_p (arg01, arg11, 0))
12997 return fold_build2_loc (loc, code, type, arg00,
12998 fold_convert_loc (loc, TREE_TYPE (arg00),
13000 if (operand_equal_p (arg01, arg10, 0))
13001 return fold_build2_loc (loc, code, type, arg00,
13002 fold_convert_loc (loc, TREE_TYPE (arg00),
13004 if (operand_equal_p (arg00, arg11, 0))
13005 return fold_build2_loc (loc, code, type, arg01,
13006 fold_convert_loc (loc, TREE_TYPE (arg01),
13008 if (operand_equal_p (arg00, arg10, 0))
13009 return fold_build2_loc (loc, code, type, arg01,
13010 fold_convert_loc (loc, TREE_TYPE (arg01),
13013 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
13014 if (TREE_CODE (arg01) == INTEGER_CST
13015 && TREE_CODE (arg11) == INTEGER_CST)
13017 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg01,
13018 fold_convert_loc (loc, itype, arg11));
13019 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00, tem);
13020 return fold_build2_loc (loc, code, type, tem,
13021 fold_convert_loc (loc, itype, arg10));
13025 /* Attempt to simplify equality/inequality comparisons of complex
13026 values. Only lower the comparison if the result is known or
13027 can be simplified to a single scalar comparison. */
13028 if ((TREE_CODE (arg0) == COMPLEX_EXPR
13029 || TREE_CODE (arg0) == COMPLEX_CST)
13030 && (TREE_CODE (arg1) == COMPLEX_EXPR
13031 || TREE_CODE (arg1) == COMPLEX_CST))
13033 tree real0, imag0, real1, imag1;
13036 if (TREE_CODE (arg0) == COMPLEX_EXPR)
13038 real0 = TREE_OPERAND (arg0, 0);
13039 imag0 = TREE_OPERAND (arg0, 1);
13043 real0 = TREE_REALPART (arg0);
13044 imag0 = TREE_IMAGPART (arg0);
13047 if (TREE_CODE (arg1) == COMPLEX_EXPR)
13049 real1 = TREE_OPERAND (arg1, 0);
13050 imag1 = TREE_OPERAND (arg1, 1);
13054 real1 = TREE_REALPART (arg1);
13055 imag1 = TREE_IMAGPART (arg1);
13058 rcond = fold_binary_loc (loc, code, type, real0, real1);
13059 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
13061 if (integer_zerop (rcond))
13063 if (code == EQ_EXPR)
13064 return omit_two_operands_loc (loc, type, boolean_false_node,
13066 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
13070 if (code == NE_EXPR)
13071 return omit_two_operands_loc (loc, type, boolean_true_node,
13073 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
13077 icond = fold_binary_loc (loc, code, type, imag0, imag1);
13078 if (icond && TREE_CODE (icond) == INTEGER_CST)
13080 if (integer_zerop (icond))
13082 if (code == EQ_EXPR)
13083 return omit_two_operands_loc (loc, type, boolean_false_node,
13085 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
13089 if (code == NE_EXPR)
13090 return omit_two_operands_loc (loc, type, boolean_true_node,
13092 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
13103 tem = fold_comparison (loc, code, type, op0, op1);
13104 if (tem != NULL_TREE)
13107 /* Transform comparisons of the form X +- C CMP X. */
13108 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
13109 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
13110 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
13111 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
13112 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
13113 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
13115 tree arg01 = TREE_OPERAND (arg0, 1);
13116 enum tree_code code0 = TREE_CODE (arg0);
13119 if (TREE_CODE (arg01) == REAL_CST)
13120 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
13122 is_positive = tree_int_cst_sgn (arg01);
13124 /* (X - c) > X becomes false. */
13125 if (code == GT_EXPR
13126 && ((code0 == MINUS_EXPR && is_positive >= 0)
13127 || (code0 == PLUS_EXPR && is_positive <= 0)))
13129 if (TREE_CODE (arg01) == INTEGER_CST
13130 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13131 fold_overflow_warning (("assuming signed overflow does not "
13132 "occur when assuming that (X - c) > X "
13133 "is always false"),
13134 WARN_STRICT_OVERFLOW_ALL);
13135 return constant_boolean_node (0, type);
13138 /* Likewise (X + c) < X becomes false. */
13139 if (code == LT_EXPR
13140 && ((code0 == PLUS_EXPR && is_positive >= 0)
13141 || (code0 == MINUS_EXPR && is_positive <= 0)))
13143 if (TREE_CODE (arg01) == INTEGER_CST
13144 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13145 fold_overflow_warning (("assuming signed overflow does not "
13146 "occur when assuming that "
13147 "(X + c) < X is always false"),
13148 WARN_STRICT_OVERFLOW_ALL);
13149 return constant_boolean_node (0, type);
13152 /* Convert (X - c) <= X to true. */
13153 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13155 && ((code0 == MINUS_EXPR && is_positive >= 0)
13156 || (code0 == PLUS_EXPR && is_positive <= 0)))
13158 if (TREE_CODE (arg01) == INTEGER_CST
13159 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13160 fold_overflow_warning (("assuming signed overflow does not "
13161 "occur when assuming that "
13162 "(X - c) <= X is always true"),
13163 WARN_STRICT_OVERFLOW_ALL);
13164 return constant_boolean_node (1, type);
13167 /* Convert (X + c) >= X to true. */
13168 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13170 && ((code0 == PLUS_EXPR && is_positive >= 0)
13171 || (code0 == MINUS_EXPR && is_positive <= 0)))
13173 if (TREE_CODE (arg01) == INTEGER_CST
13174 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13175 fold_overflow_warning (("assuming signed overflow does not "
13176 "occur when assuming that "
13177 "(X + c) >= X is always true"),
13178 WARN_STRICT_OVERFLOW_ALL);
13179 return constant_boolean_node (1, type);
13182 if (TREE_CODE (arg01) == INTEGER_CST)
13184 /* Convert X + c > X and X - c < X to true for integers. */
13185 if (code == GT_EXPR
13186 && ((code0 == PLUS_EXPR && is_positive > 0)
13187 || (code0 == MINUS_EXPR && is_positive < 0)))
13189 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13190 fold_overflow_warning (("assuming signed overflow does "
13191 "not occur when assuming that "
13192 "(X + c) > X is always true"),
13193 WARN_STRICT_OVERFLOW_ALL);
13194 return constant_boolean_node (1, type);
13197 if (code == LT_EXPR
13198 && ((code0 == MINUS_EXPR && is_positive > 0)
13199 || (code0 == PLUS_EXPR && is_positive < 0)))
13201 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13202 fold_overflow_warning (("assuming signed overflow does "
13203 "not occur when assuming that "
13204 "(X - c) < X is always true"),
13205 WARN_STRICT_OVERFLOW_ALL);
13206 return constant_boolean_node (1, type);
13209 /* Convert X + c <= X and X - c >= X to false for integers. */
13210 if (code == LE_EXPR
13211 && ((code0 == PLUS_EXPR && is_positive > 0)
13212 || (code0 == MINUS_EXPR && is_positive < 0)))
13214 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13215 fold_overflow_warning (("assuming signed overflow does "
13216 "not occur when assuming that "
13217 "(X + c) <= X is always false"),
13218 WARN_STRICT_OVERFLOW_ALL);
13219 return constant_boolean_node (0, type);
13222 if (code == GE_EXPR
13223 && ((code0 == MINUS_EXPR && is_positive > 0)
13224 || (code0 == PLUS_EXPR && is_positive < 0)))
13226 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13227 fold_overflow_warning (("assuming signed overflow does "
13228 "not occur when assuming that "
13229 "(X - c) >= X is always false"),
13230 WARN_STRICT_OVERFLOW_ALL);
13231 return constant_boolean_node (0, type);
13236 /* Comparisons with the highest or lowest possible integer of
13237 the specified precision will have known values. */
13239 tree arg1_type = TREE_TYPE (arg1);
13240 unsigned int width = TYPE_PRECISION (arg1_type);
13242 if (TREE_CODE (arg1) == INTEGER_CST
13243 && width <= 2 * HOST_BITS_PER_WIDE_INT
13244 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
13246 HOST_WIDE_INT signed_max_hi;
13247 unsigned HOST_WIDE_INT signed_max_lo;
13248 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
13250 if (width <= HOST_BITS_PER_WIDE_INT)
13252 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13257 if (TYPE_UNSIGNED (arg1_type))
13259 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13265 max_lo = signed_max_lo;
13266 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13272 width -= HOST_BITS_PER_WIDE_INT;
13273 signed_max_lo = -1;
13274 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13279 if (TYPE_UNSIGNED (arg1_type))
13281 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13286 max_hi = signed_max_hi;
13287 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13291 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
13292 && TREE_INT_CST_LOW (arg1) == max_lo)
13296 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13299 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13302 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13305 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13307 /* The GE_EXPR and LT_EXPR cases above are not normally
13308 reached because of previous transformations. */
13313 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13315 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
13319 arg1 = const_binop (PLUS_EXPR, arg1,
13320 build_int_cst (TREE_TYPE (arg1), 1));
13321 return fold_build2_loc (loc, EQ_EXPR, type,
13322 fold_convert_loc (loc,
13323 TREE_TYPE (arg1), arg0),
13326 arg1 = const_binop (PLUS_EXPR, arg1,
13327 build_int_cst (TREE_TYPE (arg1), 1));
13328 return fold_build2_loc (loc, NE_EXPR, type,
13329 fold_convert_loc (loc, TREE_TYPE (arg1),
13335 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13337 && TREE_INT_CST_LOW (arg1) == min_lo)
13341 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13344 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13347 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13350 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13355 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13357 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13361 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13362 return fold_build2_loc (loc, NE_EXPR, type,
13363 fold_convert_loc (loc,
13364 TREE_TYPE (arg1), arg0),
13367 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13368 return fold_build2_loc (loc, EQ_EXPR, type,
13369 fold_convert_loc (loc, TREE_TYPE (arg1),
13376 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13377 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13378 && TYPE_UNSIGNED (arg1_type)
13379 /* We will flip the signedness of the comparison operator
13380 associated with the mode of arg1, so the sign bit is
13381 specified by this mode. Check that arg1 is the signed
13382 max associated with this sign bit. */
13383 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13384 /* signed_type does not work on pointer types. */
13385 && INTEGRAL_TYPE_P (arg1_type))
13387 /* The following case also applies to X < signed_max+1
13388 and X >= signed_max+1 because previous transformations. */
13389 if (code == LE_EXPR || code == GT_EXPR)
13392 st = signed_type_for (TREE_TYPE (arg1));
13393 return fold_build2_loc (loc,
13394 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13395 type, fold_convert_loc (loc, st, arg0),
13396 build_int_cst (st, 0));
13402 /* If we are comparing an ABS_EXPR with a constant, we can
13403 convert all the cases into explicit comparisons, but they may
13404 well not be faster than doing the ABS and one comparison.
13405 But ABS (X) <= C is a range comparison, which becomes a subtraction
13406 and a comparison, and is probably faster. */
13407 if (code == LE_EXPR
13408 && TREE_CODE (arg1) == INTEGER_CST
13409 && TREE_CODE (arg0) == ABS_EXPR
13410 && ! TREE_SIDE_EFFECTS (arg0)
13411 && (0 != (tem = negate_expr (arg1)))
13412 && TREE_CODE (tem) == INTEGER_CST
13413 && !TREE_OVERFLOW (tem))
13414 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13415 build2 (GE_EXPR, type,
13416 TREE_OPERAND (arg0, 0), tem),
13417 build2 (LE_EXPR, type,
13418 TREE_OPERAND (arg0, 0), arg1));
13420 /* Convert ABS_EXPR<x> >= 0 to true. */
13421 strict_overflow_p = false;
13422 if (code == GE_EXPR
13423 && (integer_zerop (arg1)
13424 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13425 && real_zerop (arg1)))
13426 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13428 if (strict_overflow_p)
13429 fold_overflow_warning (("assuming signed overflow does not occur "
13430 "when simplifying comparison of "
13431 "absolute value and zero"),
13432 WARN_STRICT_OVERFLOW_CONDITIONAL);
13433 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13436 /* Convert ABS_EXPR<x> < 0 to false. */
13437 strict_overflow_p = false;
13438 if (code == LT_EXPR
13439 && (integer_zerop (arg1) || real_zerop (arg1))
13440 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13442 if (strict_overflow_p)
13443 fold_overflow_warning (("assuming signed overflow does not occur "
13444 "when simplifying comparison of "
13445 "absolute value and zero"),
13446 WARN_STRICT_OVERFLOW_CONDITIONAL);
13447 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13450 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13451 and similarly for >= into !=. */
13452 if ((code == LT_EXPR || code == GE_EXPR)
13453 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13454 && TREE_CODE (arg1) == LSHIFT_EXPR
13455 && integer_onep (TREE_OPERAND (arg1, 0)))
13456 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13457 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13458 TREE_OPERAND (arg1, 1)),
13459 build_int_cst (TREE_TYPE (arg0), 0));
13461 /* Similarly for X < (cast) (1 << Y). But cast can't be narrowing,
13462 otherwise Y might be >= # of bits in X's type and thus e.g.
13463 (unsigned char) (1 << Y) for Y 15 might be 0.
13464 If the cast is widening, then 1 << Y should have unsigned type,
13465 otherwise if Y is number of bits in the signed shift type minus 1,
13466 we can't optimize this. E.g. (unsigned long long) (1 << Y) for Y
13467 31 might be 0xffffffff80000000. */
13468 if ((code == LT_EXPR || code == GE_EXPR)
13469 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13470 && CONVERT_EXPR_P (arg1)
13471 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13472 && (TYPE_PRECISION (TREE_TYPE (arg1))
13473 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0))))
13474 && (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg1, 0)))
13475 || (TYPE_PRECISION (TREE_TYPE (arg1))
13476 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg1, 0)))))
13477 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13479 tem = build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13480 TREE_OPERAND (TREE_OPERAND (arg1, 0), 1));
13481 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13482 fold_convert_loc (loc, TREE_TYPE (arg0), tem),
13483 build_int_cst (TREE_TYPE (arg0), 0));
13488 case UNORDERED_EXPR:
13496 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13498 t1 = fold_relational_const (code, type, arg0, arg1);
13499 if (t1 != NULL_TREE)
13503 /* If the first operand is NaN, the result is constant. */
13504 if (TREE_CODE (arg0) == REAL_CST
13505 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13506 && (code != LTGT_EXPR || ! flag_trapping_math))
13508 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13509 ? integer_zero_node
13510 : integer_one_node;
13511 return omit_one_operand_loc (loc, type, t1, arg1);
13514 /* If the second operand is NaN, the result is constant. */
13515 if (TREE_CODE (arg1) == REAL_CST
13516 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13517 && (code != LTGT_EXPR || ! flag_trapping_math))
13519 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13520 ? integer_zero_node
13521 : integer_one_node;
13522 return omit_one_operand_loc (loc, type, t1, arg0);
13525 /* Simplify unordered comparison of something with itself. */
13526 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13527 && operand_equal_p (arg0, arg1, 0))
13528 return constant_boolean_node (1, type);
13530 if (code == LTGT_EXPR
13531 && !flag_trapping_math
13532 && operand_equal_p (arg0, arg1, 0))
13533 return constant_boolean_node (0, type);
13535 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13537 tree targ0 = strip_float_extensions (arg0);
13538 tree targ1 = strip_float_extensions (arg1);
13539 tree newtype = TREE_TYPE (targ0);
13541 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13542 newtype = TREE_TYPE (targ1);
13544 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13545 return fold_build2_loc (loc, code, type,
13546 fold_convert_loc (loc, newtype, targ0),
13547 fold_convert_loc (loc, newtype, targ1));
13552 case COMPOUND_EXPR:
13553 /* When pedantic, a compound expression can be neither an lvalue
13554 nor an integer constant expression. */
13555 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13557 /* Don't let (0, 0) be null pointer constant. */
13558 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13559 : fold_convert_loc (loc, type, arg1);
13560 return pedantic_non_lvalue_loc (loc, tem);
13563 if ((TREE_CODE (arg0) == REAL_CST
13564 && TREE_CODE (arg1) == REAL_CST)
13565 || (TREE_CODE (arg0) == INTEGER_CST
13566 && TREE_CODE (arg1) == INTEGER_CST))
13567 return build_complex (type, arg0, arg1);
13568 if (TREE_CODE (arg0) == REALPART_EXPR
13569 && TREE_CODE (arg1) == IMAGPART_EXPR
13570 && TREE_TYPE (TREE_OPERAND (arg0, 0)) == type
13571 && operand_equal_p (TREE_OPERAND (arg0, 0),
13572 TREE_OPERAND (arg1, 0), 0))
13573 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
13574 TREE_OPERAND (arg1, 0));
13578 /* An ASSERT_EXPR should never be passed to fold_binary. */
13579 gcc_unreachable ();
13581 case VEC_PACK_TRUNC_EXPR:
13582 case VEC_PACK_FIX_TRUNC_EXPR:
13584 unsigned int nelts = TYPE_VECTOR_SUBPARTS (type), i;
13585 tree *elts, vals = NULL_TREE;
13587 gcc_assert (TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)) == nelts / 2
13588 && TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg1)) == nelts / 2);
13589 if (TREE_CODE (arg0) != VECTOR_CST || TREE_CODE (arg1) != VECTOR_CST)
13592 elts = XALLOCAVEC (tree, nelts);
13593 if (!vec_cst_ctor_to_array (arg0, elts)
13594 || !vec_cst_ctor_to_array (arg1, elts + nelts / 2))
13597 for (i = 0; i < nelts; i++)
13599 elts[i] = fold_convert_const (code == VEC_PACK_TRUNC_EXPR
13600 ? NOP_EXPR : FIX_TRUNC_EXPR,
13601 TREE_TYPE (type), elts[i]);
13602 if (elts[i] == NULL_TREE || !CONSTANT_CLASS_P (elts[i]))
13606 for (i = 0; i < nelts; i++)
13607 vals = tree_cons (NULL_TREE, elts[nelts - i - 1], vals);
13608 return build_vector (type, vals);
13611 case VEC_WIDEN_MULT_LO_EXPR:
13612 case VEC_WIDEN_MULT_HI_EXPR:
13614 unsigned int nelts = TYPE_VECTOR_SUBPARTS (type), i;
13615 tree *elts, vals = NULL_TREE;
13617 gcc_assert (TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)) == nelts * 2
13618 && TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg1)) == nelts * 2);
13619 if (TREE_CODE (arg0) != VECTOR_CST || TREE_CODE (arg1) != VECTOR_CST)
13622 elts = XALLOCAVEC (tree, nelts * 4);
13623 if (!vec_cst_ctor_to_array (arg0, elts)
13624 || !vec_cst_ctor_to_array (arg1, elts + nelts * 2))
13627 if ((!BYTES_BIG_ENDIAN) ^ (code == VEC_WIDEN_MULT_LO_EXPR))
13630 for (i = 0; i < nelts; i++)
13632 elts[i] = fold_convert_const (NOP_EXPR, TREE_TYPE (type), elts[i]);
13633 elts[i + nelts * 2]
13634 = fold_convert_const (NOP_EXPR, TREE_TYPE (type),
13635 elts[i + nelts * 2]);
13636 if (elts[i] == NULL_TREE || elts[i + nelts * 2] == NULL_TREE)
13638 elts[i] = const_binop (MULT_EXPR, elts[i], elts[i + nelts * 2]);
13639 if (elts[i] == NULL_TREE || !CONSTANT_CLASS_P (elts[i]))
13643 for (i = 0; i < nelts; i++)
13644 vals = tree_cons (NULL_TREE, elts[nelts - i - 1], vals);
13645 return build_vector (type, vals);
13650 } /* switch (code) */
13653 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13654 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13658 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13660 switch (TREE_CODE (*tp))
13666 *walk_subtrees = 0;
13668 /* ... fall through ... */
13675 /* Return whether the sub-tree ST contains a label which is accessible from
13676 outside the sub-tree. */
13679 contains_label_p (tree st)
13682 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13685 /* Fold a ternary expression of code CODE and type TYPE with operands
13686 OP0, OP1, and OP2. Return the folded expression if folding is
13687 successful. Otherwise, return NULL_TREE. */
13690 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13691 tree op0, tree op1, tree op2)
13694 tree arg0 = NULL_TREE, arg1 = NULL_TREE, arg2 = NULL_TREE;
13695 enum tree_code_class kind = TREE_CODE_CLASS (code);
13697 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13698 && TREE_CODE_LENGTH (code) == 3);
13700 /* Strip any conversions that don't change the mode. This is safe
13701 for every expression, except for a comparison expression because
13702 its signedness is derived from its operands. So, in the latter
13703 case, only strip conversions that don't change the signedness.
13705 Note that this is done as an internal manipulation within the
13706 constant folder, in order to find the simplest representation of
13707 the arguments so that their form can be studied. In any cases,
13708 the appropriate type conversions should be put back in the tree
13709 that will get out of the constant folder. */
13730 case COMPONENT_REF:
13731 if (TREE_CODE (arg0) == CONSTRUCTOR
13732 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13734 unsigned HOST_WIDE_INT idx;
13736 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13743 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13744 so all simple results must be passed through pedantic_non_lvalue. */
13745 if (TREE_CODE (arg0) == INTEGER_CST)
13747 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13748 tem = integer_zerop (arg0) ? op2 : op1;
13749 /* Only optimize constant conditions when the selected branch
13750 has the same type as the COND_EXPR. This avoids optimizing
13751 away "c ? x : throw", where the throw has a void type.
13752 Avoid throwing away that operand which contains label. */
13753 if ((!TREE_SIDE_EFFECTS (unused_op)
13754 || !contains_label_p (unused_op))
13755 && (! VOID_TYPE_P (TREE_TYPE (tem))
13756 || VOID_TYPE_P (type)))
13757 return pedantic_non_lvalue_loc (loc, tem);
13760 if (operand_equal_p (arg1, op2, 0))
13761 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13763 /* If we have A op B ? A : C, we may be able to convert this to a
13764 simpler expression, depending on the operation and the values
13765 of B and C. Signed zeros prevent all of these transformations,
13766 for reasons given above each one.
13768 Also try swapping the arguments and inverting the conditional. */
13769 if (COMPARISON_CLASS_P (arg0)
13770 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13771 arg1, TREE_OPERAND (arg0, 1))
13772 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13774 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13779 if (COMPARISON_CLASS_P (arg0)
13780 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13782 TREE_OPERAND (arg0, 1))
13783 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13785 location_t loc0 = expr_location_or (arg0, loc);
13786 tem = fold_truth_not_expr (loc0, arg0);
13787 if (tem && COMPARISON_CLASS_P (tem))
13789 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13795 /* If the second operand is simpler than the third, swap them
13796 since that produces better jump optimization results. */
13797 if (truth_value_p (TREE_CODE (arg0))
13798 && tree_swap_operands_p (op1, op2, false))
13800 location_t loc0 = expr_location_or (arg0, loc);
13801 /* See if this can be inverted. If it can't, possibly because
13802 it was a floating-point inequality comparison, don't do
13804 tem = fold_truth_not_expr (loc0, arg0);
13806 return fold_build3_loc (loc, code, type, tem, op2, op1);
13809 /* Convert A ? 1 : 0 to simply A. */
13810 if (integer_onep (op1)
13811 && integer_zerop (op2)
13812 /* If we try to convert OP0 to our type, the
13813 call to fold will try to move the conversion inside
13814 a COND, which will recurse. In that case, the COND_EXPR
13815 is probably the best choice, so leave it alone. */
13816 && type == TREE_TYPE (arg0))
13817 return pedantic_non_lvalue_loc (loc, arg0);
13819 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13820 over COND_EXPR in cases such as floating point comparisons. */
13821 if (integer_zerop (op1)
13822 && integer_onep (op2)
13823 && truth_value_p (TREE_CODE (arg0)))
13824 return pedantic_non_lvalue_loc (loc,
13825 fold_convert_loc (loc, type,
13826 invert_truthvalue_loc (loc,
13829 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13830 if (TREE_CODE (arg0) == LT_EXPR
13831 && integer_zerop (TREE_OPERAND (arg0, 1))
13832 && integer_zerop (op2)
13833 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13835 /* sign_bit_p only checks ARG1 bits within A's precision.
13836 If <sign bit of A> has wider type than A, bits outside
13837 of A's precision in <sign bit of A> need to be checked.
13838 If they are all 0, this optimization needs to be done
13839 in unsigned A's type, if they are all 1 in signed A's type,
13840 otherwise this can't be done. */
13841 if (TYPE_PRECISION (TREE_TYPE (tem))
13842 < TYPE_PRECISION (TREE_TYPE (arg1))
13843 && TYPE_PRECISION (TREE_TYPE (tem))
13844 < TYPE_PRECISION (type))
13846 unsigned HOST_WIDE_INT mask_lo;
13847 HOST_WIDE_INT mask_hi;
13848 int inner_width, outer_width;
13851 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13852 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13853 if (outer_width > TYPE_PRECISION (type))
13854 outer_width = TYPE_PRECISION (type);
13856 if (outer_width > HOST_BITS_PER_WIDE_INT)
13858 mask_hi = ((unsigned HOST_WIDE_INT) -1
13859 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13865 mask_lo = ((unsigned HOST_WIDE_INT) -1
13866 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13868 if (inner_width > HOST_BITS_PER_WIDE_INT)
13870 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13871 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13875 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13876 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13878 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13879 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13881 tem_type = signed_type_for (TREE_TYPE (tem));
13882 tem = fold_convert_loc (loc, tem_type, tem);
13884 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13885 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13887 tem_type = unsigned_type_for (TREE_TYPE (tem));
13888 tem = fold_convert_loc (loc, tem_type, tem);
13896 fold_convert_loc (loc, type,
13897 fold_build2_loc (loc, BIT_AND_EXPR,
13898 TREE_TYPE (tem), tem,
13899 fold_convert_loc (loc,
13904 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13905 already handled above. */
13906 if (TREE_CODE (arg0) == BIT_AND_EXPR
13907 && integer_onep (TREE_OPERAND (arg0, 1))
13908 && integer_zerop (op2)
13909 && integer_pow2p (arg1))
13911 tree tem = TREE_OPERAND (arg0, 0);
13913 if (TREE_CODE (tem) == RSHIFT_EXPR
13914 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13915 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13916 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13917 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13918 TREE_OPERAND (tem, 0), arg1);
13921 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13922 is probably obsolete because the first operand should be a
13923 truth value (that's why we have the two cases above), but let's
13924 leave it in until we can confirm this for all front-ends. */
13925 if (integer_zerop (op2)
13926 && TREE_CODE (arg0) == NE_EXPR
13927 && integer_zerop (TREE_OPERAND (arg0, 1))
13928 && integer_pow2p (arg1)
13929 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13930 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13931 arg1, OEP_ONLY_CONST))
13932 return pedantic_non_lvalue_loc (loc,
13933 fold_convert_loc (loc, type,
13934 TREE_OPERAND (arg0, 0)));
13936 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13937 if (integer_zerop (op2)
13938 && truth_value_p (TREE_CODE (arg0))
13939 && truth_value_p (TREE_CODE (arg1)))
13940 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13941 fold_convert_loc (loc, type, arg0),
13944 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13945 if (integer_onep (op2)
13946 && truth_value_p (TREE_CODE (arg0))
13947 && truth_value_p (TREE_CODE (arg1)))
13949 location_t loc0 = expr_location_or (arg0, loc);
13950 /* Only perform transformation if ARG0 is easily inverted. */
13951 tem = fold_truth_not_expr (loc0, arg0);
13953 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13954 fold_convert_loc (loc, type, tem),
13958 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13959 if (integer_zerop (arg1)
13960 && truth_value_p (TREE_CODE (arg0))
13961 && truth_value_p (TREE_CODE (op2)))
13963 location_t loc0 = expr_location_or (arg0, loc);
13964 /* Only perform transformation if ARG0 is easily inverted. */
13965 tem = fold_truth_not_expr (loc0, arg0);
13967 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13968 fold_convert_loc (loc, type, tem),
13972 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13973 if (integer_onep (arg1)
13974 && truth_value_p (TREE_CODE (arg0))
13975 && truth_value_p (TREE_CODE (op2)))
13976 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13977 fold_convert_loc (loc, type, arg0),
13983 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13984 of fold_ternary on them. */
13985 gcc_unreachable ();
13987 case BIT_FIELD_REF:
13988 if ((TREE_CODE (arg0) == VECTOR_CST
13989 || TREE_CODE (arg0) == CONSTRUCTOR)
13990 && type == TREE_TYPE (TREE_TYPE (arg0)))
13992 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13993 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13996 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13997 && (idx % width) == 0
13998 && (idx = idx / width)
13999 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
14001 if (TREE_CODE (arg0) == VECTOR_CST)
14003 tree elements = TREE_VECTOR_CST_ELTS (arg0);
14004 while (idx-- > 0 && elements)
14005 elements = TREE_CHAIN (elements);
14007 return TREE_VALUE (elements);
14009 else if (idx < CONSTRUCTOR_NELTS (arg0))
14010 return CONSTRUCTOR_ELT (arg0, idx)->value;
14011 return build_zero_cst (type);
14015 /* A bit-field-ref that referenced the full argument can be stripped. */
14016 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
14017 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
14018 && integer_zerop (op2))
14019 return fold_convert_loc (loc, type, arg0);
14024 /* For integers we can decompose the FMA if possible. */
14025 if (TREE_CODE (arg0) == INTEGER_CST
14026 && TREE_CODE (arg1) == INTEGER_CST)
14027 return fold_build2_loc (loc, PLUS_EXPR, type,
14028 const_binop (MULT_EXPR, arg0, arg1), arg2);
14029 if (integer_zerop (arg2))
14030 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
14032 return fold_fma (loc, type, arg0, arg1, arg2);
14034 case VEC_PERM_EXPR:
14035 if (TREE_CODE (arg2) == VECTOR_CST)
14037 unsigned int nelts = TYPE_VECTOR_SUBPARTS (type), i;
14038 unsigned char *sel = XALLOCAVEC (unsigned char, nelts);
14040 bool need_mask_canon = false;
14042 gcc_assert (nelts == TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg2)));
14043 for (i = 0, t = TREE_VECTOR_CST_ELTS (arg2);
14044 i < nelts && t; i++, t = TREE_CHAIN (t))
14046 if (TREE_CODE (TREE_VALUE (t)) != INTEGER_CST)
14049 sel[i] = TREE_INT_CST_LOW (TREE_VALUE (t)) & (2 * nelts - 1);
14050 if (TREE_INT_CST_HIGH (TREE_VALUE (t))
14051 || ((unsigned HOST_WIDE_INT)
14052 TREE_INT_CST_LOW (TREE_VALUE (t)) != sel[i]))
14053 need_mask_canon = true;
14057 for (; i < nelts; i++)
14060 if ((TREE_CODE (arg0) == VECTOR_CST
14061 || TREE_CODE (arg0) == CONSTRUCTOR)
14062 && (TREE_CODE (arg1) == VECTOR_CST
14063 || TREE_CODE (arg1) == CONSTRUCTOR))
14065 t = fold_vec_perm (type, arg0, arg1, sel);
14066 if (t != NULL_TREE)
14070 if (need_mask_canon && arg2 == op2)
14072 tree list = NULL_TREE, eltype = TREE_TYPE (TREE_TYPE (arg2));
14073 for (i = 0; i < nelts; i++)
14074 list = tree_cons (NULL_TREE,
14075 build_int_cst (eltype, sel[nelts - i - 1]),
14077 t = build_vector (TREE_TYPE (arg2), list);
14078 return build3_loc (loc, VEC_PERM_EXPR, type, op0, op1, t);
14085 } /* switch (code) */
14088 /* Perform constant folding and related simplification of EXPR.
14089 The related simplifications include x*1 => x, x*0 => 0, etc.,
14090 and application of the associative law.
14091 NOP_EXPR conversions may be removed freely (as long as we
14092 are careful not to change the type of the overall expression).
14093 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
14094 but we can constant-fold them if they have constant operands. */
14096 #ifdef ENABLE_FOLD_CHECKING
14097 # define fold(x) fold_1 (x)
14098 static tree fold_1 (tree);
14104 const tree t = expr;
14105 enum tree_code code = TREE_CODE (t);
14106 enum tree_code_class kind = TREE_CODE_CLASS (code);
14108 location_t loc = EXPR_LOCATION (expr);
14110 /* Return right away if a constant. */
14111 if (kind == tcc_constant)
14114 /* CALL_EXPR-like objects with variable numbers of operands are
14115 treated specially. */
14116 if (kind == tcc_vl_exp)
14118 if (code == CALL_EXPR)
14120 tem = fold_call_expr (loc, expr, false);
14121 return tem ? tem : expr;
14126 if (IS_EXPR_CODE_CLASS (kind))
14128 tree type = TREE_TYPE (t);
14129 tree op0, op1, op2;
14131 switch (TREE_CODE_LENGTH (code))
14134 op0 = TREE_OPERAND (t, 0);
14135 tem = fold_unary_loc (loc, code, type, op0);
14136 return tem ? tem : expr;
14138 op0 = TREE_OPERAND (t, 0);
14139 op1 = TREE_OPERAND (t, 1);
14140 tem = fold_binary_loc (loc, code, type, op0, op1);
14141 return tem ? tem : expr;
14143 op0 = TREE_OPERAND (t, 0);
14144 op1 = TREE_OPERAND (t, 1);
14145 op2 = TREE_OPERAND (t, 2);
14146 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14147 return tem ? tem : expr;
14157 tree op0 = TREE_OPERAND (t, 0);
14158 tree op1 = TREE_OPERAND (t, 1);
14160 if (TREE_CODE (op1) == INTEGER_CST
14161 && TREE_CODE (op0) == CONSTRUCTOR
14162 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
14164 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
14165 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
14166 unsigned HOST_WIDE_INT begin = 0;
14168 /* Find a matching index by means of a binary search. */
14169 while (begin != end)
14171 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
14172 tree index = VEC_index (constructor_elt, elts, middle)->index;
14174 if (TREE_CODE (index) == INTEGER_CST
14175 && tree_int_cst_lt (index, op1))
14176 begin = middle + 1;
14177 else if (TREE_CODE (index) == INTEGER_CST
14178 && tree_int_cst_lt (op1, index))
14180 else if (TREE_CODE (index) == RANGE_EXPR
14181 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
14182 begin = middle + 1;
14183 else if (TREE_CODE (index) == RANGE_EXPR
14184 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
14187 return VEC_index (constructor_elt, elts, middle)->value;
14195 return fold (DECL_INITIAL (t));
14199 } /* switch (code) */
14202 #ifdef ENABLE_FOLD_CHECKING
14205 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
14206 static void fold_check_failed (const_tree, const_tree);
14207 void print_fold_checksum (const_tree);
14209 /* When --enable-checking=fold, compute a digest of expr before
14210 and after actual fold call to see if fold did not accidentally
14211 change original expr. */
14217 struct md5_ctx ctx;
14218 unsigned char checksum_before[16], checksum_after[16];
14221 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14222 md5_init_ctx (&ctx);
14223 fold_checksum_tree (expr, &ctx, ht);
14224 md5_finish_ctx (&ctx, checksum_before);
14227 ret = fold_1 (expr);
14229 md5_init_ctx (&ctx);
14230 fold_checksum_tree (expr, &ctx, ht);
14231 md5_finish_ctx (&ctx, checksum_after);
14234 if (memcmp (checksum_before, checksum_after, 16))
14235 fold_check_failed (expr, ret);
14241 print_fold_checksum (const_tree expr)
14243 struct md5_ctx ctx;
14244 unsigned char checksum[16], cnt;
14247 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14248 md5_init_ctx (&ctx);
14249 fold_checksum_tree (expr, &ctx, ht);
14250 md5_finish_ctx (&ctx, checksum);
14252 for (cnt = 0; cnt < 16; ++cnt)
14253 fprintf (stderr, "%02x", checksum[cnt]);
14254 putc ('\n', stderr);
14258 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
14260 internal_error ("fold check: original tree changed by fold");
14264 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
14267 enum tree_code code;
14268 union tree_node buf;
14274 slot = (void **) htab_find_slot (ht, expr, INSERT);
14277 *slot = CONST_CAST_TREE (expr);
14278 code = TREE_CODE (expr);
14279 if (TREE_CODE_CLASS (code) == tcc_declaration
14280 && DECL_ASSEMBLER_NAME_SET_P (expr))
14282 /* Allow DECL_ASSEMBLER_NAME to be modified. */
14283 memcpy ((char *) &buf, expr, tree_size (expr));
14284 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
14285 expr = (tree) &buf;
14287 else if (TREE_CODE_CLASS (code) == tcc_type
14288 && (TYPE_POINTER_TO (expr)
14289 || TYPE_REFERENCE_TO (expr)
14290 || TYPE_CACHED_VALUES_P (expr)
14291 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
14292 || TYPE_NEXT_VARIANT (expr)))
14294 /* Allow these fields to be modified. */
14296 memcpy ((char *) &buf, expr, tree_size (expr));
14297 expr = tmp = (tree) &buf;
14298 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
14299 TYPE_POINTER_TO (tmp) = NULL;
14300 TYPE_REFERENCE_TO (tmp) = NULL;
14301 TYPE_NEXT_VARIANT (tmp) = NULL;
14302 if (TYPE_CACHED_VALUES_P (tmp))
14304 TYPE_CACHED_VALUES_P (tmp) = 0;
14305 TYPE_CACHED_VALUES (tmp) = NULL;
14308 md5_process_bytes (expr, tree_size (expr), ctx);
14309 if (CODE_CONTAINS_STRUCT (code, TS_TYPED))
14310 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
14311 if (TREE_CODE_CLASS (code) != tcc_type
14312 && TREE_CODE_CLASS (code) != tcc_declaration
14313 && code != TREE_LIST
14314 && code != SSA_NAME
14315 && CODE_CONTAINS_STRUCT (code, TS_COMMON))
14316 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
14317 switch (TREE_CODE_CLASS (code))
14323 md5_process_bytes (TREE_STRING_POINTER (expr),
14324 TREE_STRING_LENGTH (expr), ctx);
14327 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
14328 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
14331 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
14337 case tcc_exceptional:
14341 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
14342 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
14343 expr = TREE_CHAIN (expr);
14344 goto recursive_label;
14347 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
14348 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
14354 case tcc_expression:
14355 case tcc_reference:
14356 case tcc_comparison:
14359 case tcc_statement:
14361 len = TREE_OPERAND_LENGTH (expr);
14362 for (i = 0; i < len; ++i)
14363 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
14365 case tcc_declaration:
14366 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
14367 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
14368 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
14370 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
14371 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
14372 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
14373 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
14374 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
14376 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
14377 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
14379 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
14381 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
14382 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
14383 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
14387 if (TREE_CODE (expr) == ENUMERAL_TYPE)
14388 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
14389 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
14390 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
14391 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
14392 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
14393 if (INTEGRAL_TYPE_P (expr)
14394 || SCALAR_FLOAT_TYPE_P (expr))
14396 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
14397 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
14399 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
14400 if (TREE_CODE (expr) == RECORD_TYPE
14401 || TREE_CODE (expr) == UNION_TYPE
14402 || TREE_CODE (expr) == QUAL_UNION_TYPE)
14403 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
14404 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
14411 /* Helper function for outputting the checksum of a tree T. When
14412 debugging with gdb, you can "define mynext" to be "next" followed
14413 by "call debug_fold_checksum (op0)", then just trace down till the
14416 DEBUG_FUNCTION void
14417 debug_fold_checksum (const_tree t)
14420 unsigned char checksum[16];
14421 struct md5_ctx ctx;
14422 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14424 md5_init_ctx (&ctx);
14425 fold_checksum_tree (t, &ctx, ht);
14426 md5_finish_ctx (&ctx, checksum);
14429 for (i = 0; i < 16; i++)
14430 fprintf (stderr, "%d ", checksum[i]);
14432 fprintf (stderr, "\n");
14437 /* Fold a unary tree expression with code CODE of type TYPE with an
14438 operand OP0. LOC is the location of the resulting expression.
14439 Return a folded expression if successful. Otherwise, return a tree
14440 expression with code CODE of type TYPE with an operand OP0. */
14443 fold_build1_stat_loc (location_t loc,
14444 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
14447 #ifdef ENABLE_FOLD_CHECKING
14448 unsigned char checksum_before[16], checksum_after[16];
14449 struct md5_ctx ctx;
14452 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14453 md5_init_ctx (&ctx);
14454 fold_checksum_tree (op0, &ctx, ht);
14455 md5_finish_ctx (&ctx, checksum_before);
14459 tem = fold_unary_loc (loc, code, type, op0);
14461 tem = build1_stat_loc (loc, code, type, op0 PASS_MEM_STAT);
14463 #ifdef ENABLE_FOLD_CHECKING
14464 md5_init_ctx (&ctx);
14465 fold_checksum_tree (op0, &ctx, ht);
14466 md5_finish_ctx (&ctx, checksum_after);
14469 if (memcmp (checksum_before, checksum_after, 16))
14470 fold_check_failed (op0, tem);
14475 /* Fold a binary tree expression with code CODE of type TYPE with
14476 operands OP0 and OP1. LOC is the location of the resulting
14477 expression. Return a folded expression if successful. Otherwise,
14478 return a tree expression with code CODE of type TYPE with operands
14482 fold_build2_stat_loc (location_t loc,
14483 enum tree_code code, tree type, tree op0, tree op1
14487 #ifdef ENABLE_FOLD_CHECKING
14488 unsigned char checksum_before_op0[16],
14489 checksum_before_op1[16],
14490 checksum_after_op0[16],
14491 checksum_after_op1[16];
14492 struct md5_ctx ctx;
14495 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14496 md5_init_ctx (&ctx);
14497 fold_checksum_tree (op0, &ctx, ht);
14498 md5_finish_ctx (&ctx, checksum_before_op0);
14501 md5_init_ctx (&ctx);
14502 fold_checksum_tree (op1, &ctx, ht);
14503 md5_finish_ctx (&ctx, checksum_before_op1);
14507 tem = fold_binary_loc (loc, code, type, op0, op1);
14509 tem = build2_stat_loc (loc, code, type, op0, op1 PASS_MEM_STAT);
14511 #ifdef ENABLE_FOLD_CHECKING
14512 md5_init_ctx (&ctx);
14513 fold_checksum_tree (op0, &ctx, ht);
14514 md5_finish_ctx (&ctx, checksum_after_op0);
14517 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14518 fold_check_failed (op0, tem);
14520 md5_init_ctx (&ctx);
14521 fold_checksum_tree (op1, &ctx, ht);
14522 md5_finish_ctx (&ctx, checksum_after_op1);
14525 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14526 fold_check_failed (op1, tem);
14531 /* Fold a ternary tree expression with code CODE of type TYPE with
14532 operands OP0, OP1, and OP2. Return a folded expression if
14533 successful. Otherwise, return a tree expression with code CODE of
14534 type TYPE with operands OP0, OP1, and OP2. */
14537 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14538 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14541 #ifdef ENABLE_FOLD_CHECKING
14542 unsigned char checksum_before_op0[16],
14543 checksum_before_op1[16],
14544 checksum_before_op2[16],
14545 checksum_after_op0[16],
14546 checksum_after_op1[16],
14547 checksum_after_op2[16];
14548 struct md5_ctx ctx;
14551 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14552 md5_init_ctx (&ctx);
14553 fold_checksum_tree (op0, &ctx, ht);
14554 md5_finish_ctx (&ctx, checksum_before_op0);
14557 md5_init_ctx (&ctx);
14558 fold_checksum_tree (op1, &ctx, ht);
14559 md5_finish_ctx (&ctx, checksum_before_op1);
14562 md5_init_ctx (&ctx);
14563 fold_checksum_tree (op2, &ctx, ht);
14564 md5_finish_ctx (&ctx, checksum_before_op2);
14568 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14569 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14571 tem = build3_stat_loc (loc, code, type, op0, op1, op2 PASS_MEM_STAT);
14573 #ifdef ENABLE_FOLD_CHECKING
14574 md5_init_ctx (&ctx);
14575 fold_checksum_tree (op0, &ctx, ht);
14576 md5_finish_ctx (&ctx, checksum_after_op0);
14579 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14580 fold_check_failed (op0, tem);
14582 md5_init_ctx (&ctx);
14583 fold_checksum_tree (op1, &ctx, ht);
14584 md5_finish_ctx (&ctx, checksum_after_op1);
14587 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14588 fold_check_failed (op1, tem);
14590 md5_init_ctx (&ctx);
14591 fold_checksum_tree (op2, &ctx, ht);
14592 md5_finish_ctx (&ctx, checksum_after_op2);
14595 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14596 fold_check_failed (op2, tem);
14601 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14602 arguments in ARGARRAY, and a null static chain.
14603 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14604 of type TYPE from the given operands as constructed by build_call_array. */
14607 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14608 int nargs, tree *argarray)
14611 #ifdef ENABLE_FOLD_CHECKING
14612 unsigned char checksum_before_fn[16],
14613 checksum_before_arglist[16],
14614 checksum_after_fn[16],
14615 checksum_after_arglist[16];
14616 struct md5_ctx ctx;
14620 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14621 md5_init_ctx (&ctx);
14622 fold_checksum_tree (fn, &ctx, ht);
14623 md5_finish_ctx (&ctx, checksum_before_fn);
14626 md5_init_ctx (&ctx);
14627 for (i = 0; i < nargs; i++)
14628 fold_checksum_tree (argarray[i], &ctx, ht);
14629 md5_finish_ctx (&ctx, checksum_before_arglist);
14633 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14635 #ifdef ENABLE_FOLD_CHECKING
14636 md5_init_ctx (&ctx);
14637 fold_checksum_tree (fn, &ctx, ht);
14638 md5_finish_ctx (&ctx, checksum_after_fn);
14641 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14642 fold_check_failed (fn, tem);
14644 md5_init_ctx (&ctx);
14645 for (i = 0; i < nargs; i++)
14646 fold_checksum_tree (argarray[i], &ctx, ht);
14647 md5_finish_ctx (&ctx, checksum_after_arglist);
14650 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14651 fold_check_failed (NULL_TREE, tem);
14656 /* Perform constant folding and related simplification of initializer
14657 expression EXPR. These behave identically to "fold_buildN" but ignore
14658 potential run-time traps and exceptions that fold must preserve. */
14660 #define START_FOLD_INIT \
14661 int saved_signaling_nans = flag_signaling_nans;\
14662 int saved_trapping_math = flag_trapping_math;\
14663 int saved_rounding_math = flag_rounding_math;\
14664 int saved_trapv = flag_trapv;\
14665 int saved_folding_initializer = folding_initializer;\
14666 flag_signaling_nans = 0;\
14667 flag_trapping_math = 0;\
14668 flag_rounding_math = 0;\
14670 folding_initializer = 1;
14672 #define END_FOLD_INIT \
14673 flag_signaling_nans = saved_signaling_nans;\
14674 flag_trapping_math = saved_trapping_math;\
14675 flag_rounding_math = saved_rounding_math;\
14676 flag_trapv = saved_trapv;\
14677 folding_initializer = saved_folding_initializer;
14680 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14681 tree type, tree op)
14686 result = fold_build1_loc (loc, code, type, op);
14693 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14694 tree type, tree op0, tree op1)
14699 result = fold_build2_loc (loc, code, type, op0, op1);
14706 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14707 tree type, tree op0, tree op1, tree op2)
14712 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14719 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14720 int nargs, tree *argarray)
14725 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14731 #undef START_FOLD_INIT
14732 #undef END_FOLD_INIT
14734 /* Determine if first argument is a multiple of second argument. Return 0 if
14735 it is not, or we cannot easily determined it to be.
14737 An example of the sort of thing we care about (at this point; this routine
14738 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14739 fold cases do now) is discovering that
14741 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14747 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14749 This code also handles discovering that
14751 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14753 is a multiple of 8 so we don't have to worry about dealing with a
14754 possible remainder.
14756 Note that we *look* inside a SAVE_EXPR only to determine how it was
14757 calculated; it is not safe for fold to do much of anything else with the
14758 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14759 at run time. For example, the latter example above *cannot* be implemented
14760 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14761 evaluation time of the original SAVE_EXPR is not necessarily the same at
14762 the time the new expression is evaluated. The only optimization of this
14763 sort that would be valid is changing
14765 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14769 SAVE_EXPR (I) * SAVE_EXPR (J)
14771 (where the same SAVE_EXPR (J) is used in the original and the
14772 transformed version). */
14775 multiple_of_p (tree type, const_tree top, const_tree bottom)
14777 if (operand_equal_p (top, bottom, 0))
14780 if (TREE_CODE (type) != INTEGER_TYPE)
14783 switch (TREE_CODE (top))
14786 /* Bitwise and provides a power of two multiple. If the mask is
14787 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14788 if (!integer_pow2p (bottom))
14793 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14794 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14798 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14799 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14802 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14806 op1 = TREE_OPERAND (top, 1);
14807 /* const_binop may not detect overflow correctly,
14808 so check for it explicitly here. */
14809 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14810 > TREE_INT_CST_LOW (op1)
14811 && TREE_INT_CST_HIGH (op1) == 0
14812 && 0 != (t1 = fold_convert (type,
14813 const_binop (LSHIFT_EXPR,
14816 && !TREE_OVERFLOW (t1))
14817 return multiple_of_p (type, t1, bottom);
14822 /* Can't handle conversions from non-integral or wider integral type. */
14823 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14824 || (TYPE_PRECISION (type)
14825 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14828 /* .. fall through ... */
14831 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14834 return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
14835 && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
14838 if (TREE_CODE (bottom) != INTEGER_CST
14839 || integer_zerop (bottom)
14840 || (TYPE_UNSIGNED (type)
14841 && (tree_int_cst_sgn (top) < 0
14842 || tree_int_cst_sgn (bottom) < 0)))
14844 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14852 /* Return true if CODE or TYPE is known to be non-negative. */
14855 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14857 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14858 && truth_value_p (code))
14859 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14860 have a signed:1 type (where the value is -1 and 0). */
14865 /* Return true if (CODE OP0) is known to be non-negative. If the return
14866 value is based on the assumption that signed overflow is undefined,
14867 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14868 *STRICT_OVERFLOW_P. */
14871 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14872 bool *strict_overflow_p)
14874 if (TYPE_UNSIGNED (type))
14880 /* We can't return 1 if flag_wrapv is set because
14881 ABS_EXPR<INT_MIN> = INT_MIN. */
14882 if (!INTEGRAL_TYPE_P (type))
14884 if (TYPE_OVERFLOW_UNDEFINED (type))
14886 *strict_overflow_p = true;
14891 case NON_LVALUE_EXPR:
14893 case FIX_TRUNC_EXPR:
14894 return tree_expr_nonnegative_warnv_p (op0,
14895 strict_overflow_p);
14899 tree inner_type = TREE_TYPE (op0);
14900 tree outer_type = type;
14902 if (TREE_CODE (outer_type) == REAL_TYPE)
14904 if (TREE_CODE (inner_type) == REAL_TYPE)
14905 return tree_expr_nonnegative_warnv_p (op0,
14906 strict_overflow_p);
14907 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14909 if (TYPE_UNSIGNED (inner_type))
14911 return tree_expr_nonnegative_warnv_p (op0,
14912 strict_overflow_p);
14915 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14917 if (TREE_CODE (inner_type) == REAL_TYPE)
14918 return tree_expr_nonnegative_warnv_p (op0,
14919 strict_overflow_p);
14920 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14921 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14922 && TYPE_UNSIGNED (inner_type);
14928 return tree_simple_nonnegative_warnv_p (code, type);
14931 /* We don't know sign of `t', so be conservative and return false. */
14935 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14936 value is based on the assumption that signed overflow is undefined,
14937 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14938 *STRICT_OVERFLOW_P. */
14941 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14942 tree op1, bool *strict_overflow_p)
14944 if (TYPE_UNSIGNED (type))
14949 case POINTER_PLUS_EXPR:
14951 if (FLOAT_TYPE_P (type))
14952 return (tree_expr_nonnegative_warnv_p (op0,
14954 && tree_expr_nonnegative_warnv_p (op1,
14955 strict_overflow_p));
14957 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14958 both unsigned and at least 2 bits shorter than the result. */
14959 if (TREE_CODE (type) == INTEGER_TYPE
14960 && TREE_CODE (op0) == NOP_EXPR
14961 && TREE_CODE (op1) == NOP_EXPR)
14963 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14964 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14965 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14966 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14968 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14969 TYPE_PRECISION (inner2)) + 1;
14970 return prec < TYPE_PRECISION (type);
14976 if (FLOAT_TYPE_P (type))
14978 /* x * x for floating point x is always non-negative. */
14979 if (operand_equal_p (op0, op1, 0))
14981 return (tree_expr_nonnegative_warnv_p (op0,
14983 && tree_expr_nonnegative_warnv_p (op1,
14984 strict_overflow_p));
14987 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14988 both unsigned and their total bits is shorter than the result. */
14989 if (TREE_CODE (type) == INTEGER_TYPE
14990 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14991 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14993 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14994 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14996 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14997 ? TREE_TYPE (TREE_OPERAND (op1, 0))
15000 bool unsigned0 = TYPE_UNSIGNED (inner0);
15001 bool unsigned1 = TYPE_UNSIGNED (inner1);
15003 if (TREE_CODE (op0) == INTEGER_CST)
15004 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
15006 if (TREE_CODE (op1) == INTEGER_CST)
15007 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
15009 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
15010 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
15012 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
15013 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
15014 : TYPE_PRECISION (inner0);
15016 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
15017 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
15018 : TYPE_PRECISION (inner1);
15020 return precision0 + precision1 < TYPE_PRECISION (type);
15027 return (tree_expr_nonnegative_warnv_p (op0,
15029 || tree_expr_nonnegative_warnv_p (op1,
15030 strict_overflow_p));
15036 case TRUNC_DIV_EXPR:
15037 case CEIL_DIV_EXPR:
15038 case FLOOR_DIV_EXPR:
15039 case ROUND_DIV_EXPR:
15040 return (tree_expr_nonnegative_warnv_p (op0,
15042 && tree_expr_nonnegative_warnv_p (op1,
15043 strict_overflow_p));
15045 case TRUNC_MOD_EXPR:
15046 case CEIL_MOD_EXPR:
15047 case FLOOR_MOD_EXPR:
15048 case ROUND_MOD_EXPR:
15049 return tree_expr_nonnegative_warnv_p (op0,
15050 strict_overflow_p);
15052 return tree_simple_nonnegative_warnv_p (code, type);
15055 /* We don't know sign of `t', so be conservative and return false. */
15059 /* Return true if T is known to be non-negative. If the return
15060 value is based on the assumption that signed overflow is undefined,
15061 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15062 *STRICT_OVERFLOW_P. */
15065 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15067 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15070 switch (TREE_CODE (t))
15073 return tree_int_cst_sgn (t) >= 0;
15076 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
15079 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
15082 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15084 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
15085 strict_overflow_p));
15087 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15090 /* We don't know sign of `t', so be conservative and return false. */
15094 /* Return true if T is known to be non-negative. If the return
15095 value is based on the assumption that signed overflow is undefined,
15096 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15097 *STRICT_OVERFLOW_P. */
15100 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
15101 tree arg0, tree arg1, bool *strict_overflow_p)
15103 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
15104 switch (DECL_FUNCTION_CODE (fndecl))
15106 CASE_FLT_FN (BUILT_IN_ACOS):
15107 CASE_FLT_FN (BUILT_IN_ACOSH):
15108 CASE_FLT_FN (BUILT_IN_CABS):
15109 CASE_FLT_FN (BUILT_IN_COSH):
15110 CASE_FLT_FN (BUILT_IN_ERFC):
15111 CASE_FLT_FN (BUILT_IN_EXP):
15112 CASE_FLT_FN (BUILT_IN_EXP10):
15113 CASE_FLT_FN (BUILT_IN_EXP2):
15114 CASE_FLT_FN (BUILT_IN_FABS):
15115 CASE_FLT_FN (BUILT_IN_FDIM):
15116 CASE_FLT_FN (BUILT_IN_HYPOT):
15117 CASE_FLT_FN (BUILT_IN_POW10):
15118 CASE_INT_FN (BUILT_IN_FFS):
15119 CASE_INT_FN (BUILT_IN_PARITY):
15120 CASE_INT_FN (BUILT_IN_POPCOUNT):
15121 case BUILT_IN_BSWAP32:
15122 case BUILT_IN_BSWAP64:
15126 CASE_FLT_FN (BUILT_IN_SQRT):
15127 /* sqrt(-0.0) is -0.0. */
15128 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
15130 return tree_expr_nonnegative_warnv_p (arg0,
15131 strict_overflow_p);
15133 CASE_FLT_FN (BUILT_IN_ASINH):
15134 CASE_FLT_FN (BUILT_IN_ATAN):
15135 CASE_FLT_FN (BUILT_IN_ATANH):
15136 CASE_FLT_FN (BUILT_IN_CBRT):
15137 CASE_FLT_FN (BUILT_IN_CEIL):
15138 CASE_FLT_FN (BUILT_IN_ERF):
15139 CASE_FLT_FN (BUILT_IN_EXPM1):
15140 CASE_FLT_FN (BUILT_IN_FLOOR):
15141 CASE_FLT_FN (BUILT_IN_FMOD):
15142 CASE_FLT_FN (BUILT_IN_FREXP):
15143 CASE_FLT_FN (BUILT_IN_ICEIL):
15144 CASE_FLT_FN (BUILT_IN_IFLOOR):
15145 CASE_FLT_FN (BUILT_IN_IRINT):
15146 CASE_FLT_FN (BUILT_IN_IROUND):
15147 CASE_FLT_FN (BUILT_IN_LCEIL):
15148 CASE_FLT_FN (BUILT_IN_LDEXP):
15149 CASE_FLT_FN (BUILT_IN_LFLOOR):
15150 CASE_FLT_FN (BUILT_IN_LLCEIL):
15151 CASE_FLT_FN (BUILT_IN_LLFLOOR):
15152 CASE_FLT_FN (BUILT_IN_LLRINT):
15153 CASE_FLT_FN (BUILT_IN_LLROUND):
15154 CASE_FLT_FN (BUILT_IN_LRINT):
15155 CASE_FLT_FN (BUILT_IN_LROUND):
15156 CASE_FLT_FN (BUILT_IN_MODF):
15157 CASE_FLT_FN (BUILT_IN_NEARBYINT):
15158 CASE_FLT_FN (BUILT_IN_RINT):
15159 CASE_FLT_FN (BUILT_IN_ROUND):
15160 CASE_FLT_FN (BUILT_IN_SCALB):
15161 CASE_FLT_FN (BUILT_IN_SCALBLN):
15162 CASE_FLT_FN (BUILT_IN_SCALBN):
15163 CASE_FLT_FN (BUILT_IN_SIGNBIT):
15164 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
15165 CASE_FLT_FN (BUILT_IN_SINH):
15166 CASE_FLT_FN (BUILT_IN_TANH):
15167 CASE_FLT_FN (BUILT_IN_TRUNC):
15168 /* True if the 1st argument is nonnegative. */
15169 return tree_expr_nonnegative_warnv_p (arg0,
15170 strict_overflow_p);
15172 CASE_FLT_FN (BUILT_IN_FMAX):
15173 /* True if the 1st OR 2nd arguments are nonnegative. */
15174 return (tree_expr_nonnegative_warnv_p (arg0,
15176 || (tree_expr_nonnegative_warnv_p (arg1,
15177 strict_overflow_p)));
15179 CASE_FLT_FN (BUILT_IN_FMIN):
15180 /* True if the 1st AND 2nd arguments are nonnegative. */
15181 return (tree_expr_nonnegative_warnv_p (arg0,
15183 && (tree_expr_nonnegative_warnv_p (arg1,
15184 strict_overflow_p)));
15186 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15187 /* True if the 2nd argument is nonnegative. */
15188 return tree_expr_nonnegative_warnv_p (arg1,
15189 strict_overflow_p);
15191 CASE_FLT_FN (BUILT_IN_POWI):
15192 /* True if the 1st argument is nonnegative or the second
15193 argument is an even integer. */
15194 if (TREE_CODE (arg1) == INTEGER_CST
15195 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
15197 return tree_expr_nonnegative_warnv_p (arg0,
15198 strict_overflow_p);
15200 CASE_FLT_FN (BUILT_IN_POW):
15201 /* True if the 1st argument is nonnegative or the second
15202 argument is an even integer valued real. */
15203 if (TREE_CODE (arg1) == REAL_CST)
15208 c = TREE_REAL_CST (arg1);
15209 n = real_to_integer (&c);
15212 REAL_VALUE_TYPE cint;
15213 real_from_integer (&cint, VOIDmode, n,
15214 n < 0 ? -1 : 0, 0);
15215 if (real_identical (&c, &cint))
15219 return tree_expr_nonnegative_warnv_p (arg0,
15220 strict_overflow_p);
15225 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
15229 /* Return true if T is known to be non-negative. If the return
15230 value is based on the assumption that signed overflow is undefined,
15231 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15232 *STRICT_OVERFLOW_P. */
15235 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15237 enum tree_code code = TREE_CODE (t);
15238 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15245 tree temp = TARGET_EXPR_SLOT (t);
15246 t = TARGET_EXPR_INITIAL (t);
15248 /* If the initializer is non-void, then it's a normal expression
15249 that will be assigned to the slot. */
15250 if (!VOID_TYPE_P (t))
15251 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
15253 /* Otherwise, the initializer sets the slot in some way. One common
15254 way is an assignment statement at the end of the initializer. */
15257 if (TREE_CODE (t) == BIND_EXPR)
15258 t = expr_last (BIND_EXPR_BODY (t));
15259 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
15260 || TREE_CODE (t) == TRY_CATCH_EXPR)
15261 t = expr_last (TREE_OPERAND (t, 0));
15262 else if (TREE_CODE (t) == STATEMENT_LIST)
15267 if (TREE_CODE (t) == MODIFY_EXPR
15268 && TREE_OPERAND (t, 0) == temp)
15269 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15270 strict_overflow_p);
15277 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
15278 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
15280 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
15281 get_callee_fndecl (t),
15284 strict_overflow_p);
15286 case COMPOUND_EXPR:
15288 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15289 strict_overflow_p);
15291 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
15292 strict_overflow_p);
15294 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
15295 strict_overflow_p);
15298 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15302 /* We don't know sign of `t', so be conservative and return false. */
15306 /* Return true if T is known to be non-negative. If the return
15307 value is based on the assumption that signed overflow is undefined,
15308 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15309 *STRICT_OVERFLOW_P. */
15312 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15314 enum tree_code code;
15315 if (t == error_mark_node)
15318 code = TREE_CODE (t);
15319 switch (TREE_CODE_CLASS (code))
15322 case tcc_comparison:
15323 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15325 TREE_OPERAND (t, 0),
15326 TREE_OPERAND (t, 1),
15327 strict_overflow_p);
15330 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15332 TREE_OPERAND (t, 0),
15333 strict_overflow_p);
15336 case tcc_declaration:
15337 case tcc_reference:
15338 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15346 case TRUTH_AND_EXPR:
15347 case TRUTH_OR_EXPR:
15348 case TRUTH_XOR_EXPR:
15349 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15351 TREE_OPERAND (t, 0),
15352 TREE_OPERAND (t, 1),
15353 strict_overflow_p);
15354 case TRUTH_NOT_EXPR:
15355 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15357 TREE_OPERAND (t, 0),
15358 strict_overflow_p);
15365 case WITH_SIZE_EXPR:
15367 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15370 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
15374 /* Return true if `t' is known to be non-negative. Handle warnings
15375 about undefined signed overflow. */
15378 tree_expr_nonnegative_p (tree t)
15380 bool ret, strict_overflow_p;
15382 strict_overflow_p = false;
15383 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
15384 if (strict_overflow_p)
15385 fold_overflow_warning (("assuming signed overflow does not occur when "
15386 "determining that expression is always "
15388 WARN_STRICT_OVERFLOW_MISC);
15393 /* Return true when (CODE OP0) is an address and is known to be nonzero.
15394 For floating point we further ensure that T is not denormal.
15395 Similar logic is present in nonzero_address in rtlanal.h.
15397 If the return value is based on the assumption that signed overflow
15398 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15399 change *STRICT_OVERFLOW_P. */
15402 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
15403 bool *strict_overflow_p)
15408 return tree_expr_nonzero_warnv_p (op0,
15409 strict_overflow_p);
15413 tree inner_type = TREE_TYPE (op0);
15414 tree outer_type = type;
15416 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
15417 && tree_expr_nonzero_warnv_p (op0,
15418 strict_overflow_p));
15422 case NON_LVALUE_EXPR:
15423 return tree_expr_nonzero_warnv_p (op0,
15424 strict_overflow_p);
15433 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
15434 For floating point we further ensure that T is not denormal.
15435 Similar logic is present in nonzero_address in rtlanal.h.
15437 If the return value is based on the assumption that signed overflow
15438 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15439 change *STRICT_OVERFLOW_P. */
15442 tree_binary_nonzero_warnv_p (enum tree_code code,
15445 tree op1, bool *strict_overflow_p)
15447 bool sub_strict_overflow_p;
15450 case POINTER_PLUS_EXPR:
15452 if (TYPE_OVERFLOW_UNDEFINED (type))
15454 /* With the presence of negative values it is hard
15455 to say something. */
15456 sub_strict_overflow_p = false;
15457 if (!tree_expr_nonnegative_warnv_p (op0,
15458 &sub_strict_overflow_p)
15459 || !tree_expr_nonnegative_warnv_p (op1,
15460 &sub_strict_overflow_p))
15462 /* One of operands must be positive and the other non-negative. */
15463 /* We don't set *STRICT_OVERFLOW_P here: even if this value
15464 overflows, on a twos-complement machine the sum of two
15465 nonnegative numbers can never be zero. */
15466 return (tree_expr_nonzero_warnv_p (op0,
15468 || tree_expr_nonzero_warnv_p (op1,
15469 strict_overflow_p));
15474 if (TYPE_OVERFLOW_UNDEFINED (type))
15476 if (tree_expr_nonzero_warnv_p (op0,
15478 && tree_expr_nonzero_warnv_p (op1,
15479 strict_overflow_p))
15481 *strict_overflow_p = true;
15488 sub_strict_overflow_p = false;
15489 if (tree_expr_nonzero_warnv_p (op0,
15490 &sub_strict_overflow_p)
15491 && tree_expr_nonzero_warnv_p (op1,
15492 &sub_strict_overflow_p))
15494 if (sub_strict_overflow_p)
15495 *strict_overflow_p = true;
15500 sub_strict_overflow_p = false;
15501 if (tree_expr_nonzero_warnv_p (op0,
15502 &sub_strict_overflow_p))
15504 if (sub_strict_overflow_p)
15505 *strict_overflow_p = true;
15507 /* When both operands are nonzero, then MAX must be too. */
15508 if (tree_expr_nonzero_warnv_p (op1,
15509 strict_overflow_p))
15512 /* MAX where operand 0 is positive is positive. */
15513 return tree_expr_nonnegative_warnv_p (op0,
15514 strict_overflow_p);
15516 /* MAX where operand 1 is positive is positive. */
15517 else if (tree_expr_nonzero_warnv_p (op1,
15518 &sub_strict_overflow_p)
15519 && tree_expr_nonnegative_warnv_p (op1,
15520 &sub_strict_overflow_p))
15522 if (sub_strict_overflow_p)
15523 *strict_overflow_p = true;
15529 return (tree_expr_nonzero_warnv_p (op1,
15531 || tree_expr_nonzero_warnv_p (op0,
15532 strict_overflow_p));
15541 /* Return true when T is an address and is known to be nonzero.
15542 For floating point we further ensure that T is not denormal.
15543 Similar logic is present in nonzero_address in rtlanal.h.
15545 If the return value is based on the assumption that signed overflow
15546 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15547 change *STRICT_OVERFLOW_P. */
15550 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15552 bool sub_strict_overflow_p;
15553 switch (TREE_CODE (t))
15556 return !integer_zerop (t);
15560 tree base = TREE_OPERAND (t, 0);
15561 if (!DECL_P (base))
15562 base = get_base_address (base);
15567 /* Weak declarations may link to NULL. Other things may also be NULL
15568 so protect with -fdelete-null-pointer-checks; but not variables
15569 allocated on the stack. */
15571 && (flag_delete_null_pointer_checks
15572 || (DECL_CONTEXT (base)
15573 && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
15574 && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
15575 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15577 /* Constants are never weak. */
15578 if (CONSTANT_CLASS_P (base))
15585 sub_strict_overflow_p = false;
15586 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15587 &sub_strict_overflow_p)
15588 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15589 &sub_strict_overflow_p))
15591 if (sub_strict_overflow_p)
15592 *strict_overflow_p = true;
15603 /* Return true when T is an address and is known to be nonzero.
15604 For floating point we further ensure that T is not denormal.
15605 Similar logic is present in nonzero_address in rtlanal.h.
15607 If the return value is based on the assumption that signed overflow
15608 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15609 change *STRICT_OVERFLOW_P. */
15612 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15614 tree type = TREE_TYPE (t);
15615 enum tree_code code;
15617 /* Doing something useful for floating point would need more work. */
15618 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15621 code = TREE_CODE (t);
15622 switch (TREE_CODE_CLASS (code))
15625 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15626 strict_overflow_p);
15628 case tcc_comparison:
15629 return tree_binary_nonzero_warnv_p (code, type,
15630 TREE_OPERAND (t, 0),
15631 TREE_OPERAND (t, 1),
15632 strict_overflow_p);
15634 case tcc_declaration:
15635 case tcc_reference:
15636 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15644 case TRUTH_NOT_EXPR:
15645 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15646 strict_overflow_p);
15648 case TRUTH_AND_EXPR:
15649 case TRUTH_OR_EXPR:
15650 case TRUTH_XOR_EXPR:
15651 return tree_binary_nonzero_warnv_p (code, type,
15652 TREE_OPERAND (t, 0),
15653 TREE_OPERAND (t, 1),
15654 strict_overflow_p);
15661 case WITH_SIZE_EXPR:
15663 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15665 case COMPOUND_EXPR:
15668 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15669 strict_overflow_p);
15672 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15673 strict_overflow_p);
15676 return alloca_call_p (t);
15684 /* Return true when T is an address and is known to be nonzero.
15685 Handle warnings about undefined signed overflow. */
15688 tree_expr_nonzero_p (tree t)
15690 bool ret, strict_overflow_p;
15692 strict_overflow_p = false;
15693 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15694 if (strict_overflow_p)
15695 fold_overflow_warning (("assuming signed overflow does not occur when "
15696 "determining that expression is always "
15698 WARN_STRICT_OVERFLOW_MISC);
15702 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15703 attempt to fold the expression to a constant without modifying TYPE,
15706 If the expression could be simplified to a constant, then return
15707 the constant. If the expression would not be simplified to a
15708 constant, then return NULL_TREE. */
15711 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15713 tree tem = fold_binary (code, type, op0, op1);
15714 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15717 /* Given the components of a unary expression CODE, TYPE and OP0,
15718 attempt to fold the expression to a constant without modifying
15721 If the expression could be simplified to a constant, then return
15722 the constant. If the expression would not be simplified to a
15723 constant, then return NULL_TREE. */
15726 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15728 tree tem = fold_unary (code, type, op0);
15729 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15732 /* If EXP represents referencing an element in a constant string
15733 (either via pointer arithmetic or array indexing), return the
15734 tree representing the value accessed, otherwise return NULL. */
15737 fold_read_from_constant_string (tree exp)
15739 if ((TREE_CODE (exp) == INDIRECT_REF
15740 || TREE_CODE (exp) == ARRAY_REF)
15741 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15743 tree exp1 = TREE_OPERAND (exp, 0);
15746 location_t loc = EXPR_LOCATION (exp);
15748 if (TREE_CODE (exp) == INDIRECT_REF)
15749 string = string_constant (exp1, &index);
15752 tree low_bound = array_ref_low_bound (exp);
15753 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15755 /* Optimize the special-case of a zero lower bound.
15757 We convert the low_bound to sizetype to avoid some problems
15758 with constant folding. (E.g. suppose the lower bound is 1,
15759 and its mode is QI. Without the conversion,l (ARRAY
15760 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15761 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15762 if (! integer_zerop (low_bound))
15763 index = size_diffop_loc (loc, index,
15764 fold_convert_loc (loc, sizetype, low_bound));
15770 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15771 && TREE_CODE (string) == STRING_CST
15772 && TREE_CODE (index) == INTEGER_CST
15773 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15774 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15776 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15777 return build_int_cst_type (TREE_TYPE (exp),
15778 (TREE_STRING_POINTER (string)
15779 [TREE_INT_CST_LOW (index)]));
15784 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15785 an integer constant, real, or fixed-point constant.
15787 TYPE is the type of the result. */
15790 fold_negate_const (tree arg0, tree type)
15792 tree t = NULL_TREE;
15794 switch (TREE_CODE (arg0))
15798 double_int val = tree_to_double_int (arg0);
15799 int overflow = neg_double (val.low, val.high, &val.low, &val.high);
15801 t = force_fit_type_double (type, val, 1,
15802 (overflow | TREE_OVERFLOW (arg0))
15803 && !TYPE_UNSIGNED (type));
15808 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15813 FIXED_VALUE_TYPE f;
15814 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15815 &(TREE_FIXED_CST (arg0)), NULL,
15816 TYPE_SATURATING (type));
15817 t = build_fixed (type, f);
15818 /* Propagate overflow flags. */
15819 if (overflow_p | TREE_OVERFLOW (arg0))
15820 TREE_OVERFLOW (t) = 1;
15825 gcc_unreachable ();
15831 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15832 an integer constant or real constant.
15834 TYPE is the type of the result. */
15837 fold_abs_const (tree arg0, tree type)
15839 tree t = NULL_TREE;
15841 switch (TREE_CODE (arg0))
15845 double_int val = tree_to_double_int (arg0);
15847 /* If the value is unsigned or non-negative, then the absolute value
15848 is the same as the ordinary value. */
15849 if (TYPE_UNSIGNED (type)
15850 || !double_int_negative_p (val))
15853 /* If the value is negative, then the absolute value is
15859 overflow = neg_double (val.low, val.high, &val.low, &val.high);
15860 t = force_fit_type_double (type, val, -1,
15861 overflow | TREE_OVERFLOW (arg0));
15867 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15868 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15874 gcc_unreachable ();
15880 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15881 constant. TYPE is the type of the result. */
15884 fold_not_const (const_tree arg0, tree type)
15888 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15890 val = double_int_not (tree_to_double_int (arg0));
15891 return force_fit_type_double (type, val, 0, TREE_OVERFLOW (arg0));
15894 /* Given CODE, a relational operator, the target type, TYPE and two
15895 constant operands OP0 and OP1, return the result of the
15896 relational operation. If the result is not a compile time
15897 constant, then return NULL_TREE. */
15900 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15902 int result, invert;
15904 /* From here on, the only cases we handle are when the result is
15905 known to be a constant. */
15907 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15909 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15910 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15912 /* Handle the cases where either operand is a NaN. */
15913 if (real_isnan (c0) || real_isnan (c1))
15923 case UNORDERED_EXPR:
15937 if (flag_trapping_math)
15943 gcc_unreachable ();
15946 return constant_boolean_node (result, type);
15949 return constant_boolean_node (real_compare (code, c0, c1), type);
15952 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15954 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15955 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15956 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15959 /* Handle equality/inequality of complex constants. */
15960 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15962 tree rcond = fold_relational_const (code, type,
15963 TREE_REALPART (op0),
15964 TREE_REALPART (op1));
15965 tree icond = fold_relational_const (code, type,
15966 TREE_IMAGPART (op0),
15967 TREE_IMAGPART (op1));
15968 if (code == EQ_EXPR)
15969 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15970 else if (code == NE_EXPR)
15971 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15976 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15978 To compute GT, swap the arguments and do LT.
15979 To compute GE, do LT and invert the result.
15980 To compute LE, swap the arguments, do LT and invert the result.
15981 To compute NE, do EQ and invert the result.
15983 Therefore, the code below must handle only EQ and LT. */
15985 if (code == LE_EXPR || code == GT_EXPR)
15990 code = swap_tree_comparison (code);
15993 /* Note that it is safe to invert for real values here because we
15994 have already handled the one case that it matters. */
15997 if (code == NE_EXPR || code == GE_EXPR)
16000 code = invert_tree_comparison (code, false);
16003 /* Compute a result for LT or EQ if args permit;
16004 Otherwise return T. */
16005 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
16007 if (code == EQ_EXPR)
16008 result = tree_int_cst_equal (op0, op1);
16009 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
16010 result = INT_CST_LT_UNSIGNED (op0, op1);
16012 result = INT_CST_LT (op0, op1);
16019 return constant_boolean_node (result, type);
16022 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
16023 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
16027 fold_build_cleanup_point_expr (tree type, tree expr)
16029 /* If the expression does not have side effects then we don't have to wrap
16030 it with a cleanup point expression. */
16031 if (!TREE_SIDE_EFFECTS (expr))
16034 /* If the expression is a return, check to see if the expression inside the
16035 return has no side effects or the right hand side of the modify expression
16036 inside the return. If either don't have side effects set we don't need to
16037 wrap the expression in a cleanup point expression. Note we don't check the
16038 left hand side of the modify because it should always be a return decl. */
16039 if (TREE_CODE (expr) == RETURN_EXPR)
16041 tree op = TREE_OPERAND (expr, 0);
16042 if (!op || !TREE_SIDE_EFFECTS (op))
16044 op = TREE_OPERAND (op, 1);
16045 if (!TREE_SIDE_EFFECTS (op))
16049 return build1 (CLEANUP_POINT_EXPR, type, expr);
16052 /* Given a pointer value OP0 and a type TYPE, return a simplified version
16053 of an indirection through OP0, or NULL_TREE if no simplification is
16057 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
16063 subtype = TREE_TYPE (sub);
16064 if (!POINTER_TYPE_P (subtype))
16067 if (TREE_CODE (sub) == ADDR_EXPR)
16069 tree op = TREE_OPERAND (sub, 0);
16070 tree optype = TREE_TYPE (op);
16071 /* *&CONST_DECL -> to the value of the const decl. */
16072 if (TREE_CODE (op) == CONST_DECL)
16073 return DECL_INITIAL (op);
16074 /* *&p => p; make sure to handle *&"str"[cst] here. */
16075 if (type == optype)
16077 tree fop = fold_read_from_constant_string (op);
16083 /* *(foo *)&fooarray => fooarray[0] */
16084 else if (TREE_CODE (optype) == ARRAY_TYPE
16085 && type == TREE_TYPE (optype)
16086 && (!in_gimple_form
16087 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
16089 tree type_domain = TYPE_DOMAIN (optype);
16090 tree min_val = size_zero_node;
16091 if (type_domain && TYPE_MIN_VALUE (type_domain))
16092 min_val = TYPE_MIN_VALUE (type_domain);
16094 && TREE_CODE (min_val) != INTEGER_CST)
16096 return build4_loc (loc, ARRAY_REF, type, op, min_val,
16097 NULL_TREE, NULL_TREE);
16099 /* *(foo *)&complexfoo => __real__ complexfoo */
16100 else if (TREE_CODE (optype) == COMPLEX_TYPE
16101 && type == TREE_TYPE (optype))
16102 return fold_build1_loc (loc, REALPART_EXPR, type, op);
16103 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
16104 else if (TREE_CODE (optype) == VECTOR_TYPE
16105 && type == TREE_TYPE (optype))
16107 tree part_width = TYPE_SIZE (type);
16108 tree index = bitsize_int (0);
16109 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
16113 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
16114 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
16116 tree op00 = TREE_OPERAND (sub, 0);
16117 tree op01 = TREE_OPERAND (sub, 1);
16120 if (TREE_CODE (op00) == ADDR_EXPR)
16123 op00 = TREE_OPERAND (op00, 0);
16124 op00type = TREE_TYPE (op00);
16126 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
16127 if (TREE_CODE (op00type) == VECTOR_TYPE
16128 && type == TREE_TYPE (op00type))
16130 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
16131 tree part_width = TYPE_SIZE (type);
16132 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
16133 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
16134 tree index = bitsize_int (indexi);
16136 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (op00type))
16137 return fold_build3_loc (loc,
16138 BIT_FIELD_REF, type, op00,
16139 part_width, index);
16142 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
16143 else if (TREE_CODE (op00type) == COMPLEX_TYPE
16144 && type == TREE_TYPE (op00type))
16146 tree size = TYPE_SIZE_UNIT (type);
16147 if (tree_int_cst_equal (size, op01))
16148 return fold_build1_loc (loc, IMAGPART_EXPR, type, op00);
16150 /* ((foo *)&fooarray)[1] => fooarray[1] */
16151 else if (TREE_CODE (op00type) == ARRAY_TYPE
16152 && type == TREE_TYPE (op00type))
16154 tree type_domain = TYPE_DOMAIN (op00type);
16155 tree min_val = size_zero_node;
16156 if (type_domain && TYPE_MIN_VALUE (type_domain))
16157 min_val = TYPE_MIN_VALUE (type_domain);
16158 op01 = size_binop_loc (loc, EXACT_DIV_EXPR, op01,
16159 TYPE_SIZE_UNIT (type));
16160 op01 = size_binop_loc (loc, PLUS_EXPR, op01, min_val);
16161 return build4_loc (loc, ARRAY_REF, type, op00, op01,
16162 NULL_TREE, NULL_TREE);
16167 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
16168 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
16169 && type == TREE_TYPE (TREE_TYPE (subtype))
16170 && (!in_gimple_form
16171 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
16174 tree min_val = size_zero_node;
16175 sub = build_fold_indirect_ref_loc (loc, sub);
16176 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
16177 if (type_domain && TYPE_MIN_VALUE (type_domain))
16178 min_val = TYPE_MIN_VALUE (type_domain);
16180 && TREE_CODE (min_val) != INTEGER_CST)
16182 return build4_loc (loc, ARRAY_REF, type, sub, min_val, NULL_TREE,
16189 /* Builds an expression for an indirection through T, simplifying some
16193 build_fold_indirect_ref_loc (location_t loc, tree t)
16195 tree type = TREE_TYPE (TREE_TYPE (t));
16196 tree sub = fold_indirect_ref_1 (loc, type, t);
16201 return build1_loc (loc, INDIRECT_REF, type, t);
16204 /* Given an INDIRECT_REF T, return either T or a simplified version. */
16207 fold_indirect_ref_loc (location_t loc, tree t)
16209 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
16217 /* Strip non-trapping, non-side-effecting tree nodes from an expression
16218 whose result is ignored. The type of the returned tree need not be
16219 the same as the original expression. */
16222 fold_ignored_result (tree t)
16224 if (!TREE_SIDE_EFFECTS (t))
16225 return integer_zero_node;
16228 switch (TREE_CODE_CLASS (TREE_CODE (t)))
16231 t = TREE_OPERAND (t, 0);
16235 case tcc_comparison:
16236 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16237 t = TREE_OPERAND (t, 0);
16238 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
16239 t = TREE_OPERAND (t, 1);
16244 case tcc_expression:
16245 switch (TREE_CODE (t))
16247 case COMPOUND_EXPR:
16248 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16250 t = TREE_OPERAND (t, 0);
16254 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
16255 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
16257 t = TREE_OPERAND (t, 0);
16270 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
16271 This can only be applied to objects of a sizetype. */
16274 round_up_loc (location_t loc, tree value, int divisor)
16276 tree div = NULL_TREE;
16278 gcc_assert (divisor > 0);
16282 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16283 have to do anything. Only do this when we are not given a const,
16284 because in that case, this check is more expensive than just
16286 if (TREE_CODE (value) != INTEGER_CST)
16288 div = build_int_cst (TREE_TYPE (value), divisor);
16290 if (multiple_of_p (TREE_TYPE (value), value, div))
16294 /* If divisor is a power of two, simplify this to bit manipulation. */
16295 if (divisor == (divisor & -divisor))
16297 if (TREE_CODE (value) == INTEGER_CST)
16299 double_int val = tree_to_double_int (value);
16302 if ((val.low & (divisor - 1)) == 0)
16305 overflow_p = TREE_OVERFLOW (value);
16306 val.low &= ~(divisor - 1);
16307 val.low += divisor;
16315 return force_fit_type_double (TREE_TYPE (value), val,
16322 t = build_int_cst (TREE_TYPE (value), divisor - 1);
16323 value = size_binop_loc (loc, PLUS_EXPR, value, t);
16324 t = build_int_cst (TREE_TYPE (value), -divisor);
16325 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16331 div = build_int_cst (TREE_TYPE (value), divisor);
16332 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
16333 value = size_binop_loc (loc, MULT_EXPR, value, div);
16339 /* Likewise, but round down. */
16342 round_down_loc (location_t loc, tree value, int divisor)
16344 tree div = NULL_TREE;
16346 gcc_assert (divisor > 0);
16350 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16351 have to do anything. Only do this when we are not given a const,
16352 because in that case, this check is more expensive than just
16354 if (TREE_CODE (value) != INTEGER_CST)
16356 div = build_int_cst (TREE_TYPE (value), divisor);
16358 if (multiple_of_p (TREE_TYPE (value), value, div))
16362 /* If divisor is a power of two, simplify this to bit manipulation. */
16363 if (divisor == (divisor & -divisor))
16367 t = build_int_cst (TREE_TYPE (value), -divisor);
16368 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16373 div = build_int_cst (TREE_TYPE (value), divisor);
16374 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
16375 value = size_binop_loc (loc, MULT_EXPR, value, div);
16381 /* Returns the pointer to the base of the object addressed by EXP and
16382 extracts the information about the offset of the access, storing it
16383 to PBITPOS and POFFSET. */
16386 split_address_to_core_and_offset (tree exp,
16387 HOST_WIDE_INT *pbitpos, tree *poffset)
16390 enum machine_mode mode;
16391 int unsignedp, volatilep;
16392 HOST_WIDE_INT bitsize;
16393 location_t loc = EXPR_LOCATION (exp);
16395 if (TREE_CODE (exp) == ADDR_EXPR)
16397 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
16398 poffset, &mode, &unsignedp, &volatilep,
16400 core = build_fold_addr_expr_loc (loc, core);
16406 *poffset = NULL_TREE;
16412 /* Returns true if addresses of E1 and E2 differ by a constant, false
16413 otherwise. If they do, E1 - E2 is stored in *DIFF. */
16416 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
16419 HOST_WIDE_INT bitpos1, bitpos2;
16420 tree toffset1, toffset2, tdiff, type;
16422 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
16423 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
16425 if (bitpos1 % BITS_PER_UNIT != 0
16426 || bitpos2 % BITS_PER_UNIT != 0
16427 || !operand_equal_p (core1, core2, 0))
16430 if (toffset1 && toffset2)
16432 type = TREE_TYPE (toffset1);
16433 if (type != TREE_TYPE (toffset2))
16434 toffset2 = fold_convert (type, toffset2);
16436 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
16437 if (!cst_and_fits_in_hwi (tdiff))
16440 *diff = int_cst_value (tdiff);
16442 else if (toffset1 || toffset2)
16444 /* If only one of the offsets is non-constant, the difference cannot
16451 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
16455 /* Simplify the floating point expression EXP when the sign of the
16456 result is not significant. Return NULL_TREE if no simplification
16460 fold_strip_sign_ops (tree exp)
16463 location_t loc = EXPR_LOCATION (exp);
16465 switch (TREE_CODE (exp))
16469 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16470 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
16474 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
16476 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16477 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16478 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
16479 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
16480 arg0 ? arg0 : TREE_OPERAND (exp, 0),
16481 arg1 ? arg1 : TREE_OPERAND (exp, 1));
16484 case COMPOUND_EXPR:
16485 arg0 = TREE_OPERAND (exp, 0);
16486 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16488 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
16492 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16493 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
16495 return fold_build3_loc (loc,
16496 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
16497 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16498 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16503 const enum built_in_function fcode = builtin_mathfn_code (exp);
16506 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16507 /* Strip copysign function call, return the 1st argument. */
16508 arg0 = CALL_EXPR_ARG (exp, 0);
16509 arg1 = CALL_EXPR_ARG (exp, 1);
16510 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16513 /* Strip sign ops from the argument of "odd" math functions. */
16514 if (negate_mathfn_p (fcode))
16516 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16518 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);