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 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 tree range_binop (enum tree_code, tree, tree, int, tree, int);
116 static tree range_predecessor (tree);
117 static tree range_successor (tree);
118 extern tree make_range (tree, int *, tree *, tree *, bool *);
119 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
121 static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
122 static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
123 static tree unextend (tree, int, int, tree);
124 static tree fold_truthop (location_t, enum tree_code, tree, tree, tree);
125 static tree optimize_minmax_comparison (location_t, enum tree_code,
127 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
128 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
129 static tree fold_binary_op_with_conditional_arg (location_t,
130 enum tree_code, tree,
133 static tree fold_mathfn_compare (location_t,
134 enum built_in_function, enum tree_code,
136 static tree fold_inf_compare (location_t, enum tree_code, tree, tree, tree);
137 static tree fold_div_compare (location_t, enum tree_code, tree, tree, tree);
138 static bool reorder_operands_p (const_tree, const_tree);
139 static tree fold_negate_const (tree, tree);
140 static tree fold_not_const (const_tree, tree);
141 static tree fold_relational_const (enum tree_code, tree, tree, tree);
142 static tree fold_convert_const (enum tree_code, tree, tree);
144 /* Return EXPR_LOCATION of T if it is not UNKNOWN_LOCATION.
145 Otherwise, return LOC. */
148 expr_location_or (tree t, location_t loc)
150 location_t tloc = EXPR_LOCATION (t);
151 return tloc != UNKNOWN_LOCATION ? tloc : loc;
154 /* Similar to protected_set_expr_location, but never modify x in place,
155 if location can and needs to be set, unshare it. */
158 protected_set_expr_location_unshare (tree x, location_t loc)
160 if (CAN_HAVE_LOCATION_P (x)
161 && EXPR_LOCATION (x) != loc
162 && !(TREE_CODE (x) == SAVE_EXPR
163 || TREE_CODE (x) == TARGET_EXPR
164 || TREE_CODE (x) == BIND_EXPR))
167 SET_EXPR_LOCATION (x, loc);
173 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
174 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
175 and SUM1. Then this yields nonzero if overflow occurred during the
178 Overflow occurs if A and B have the same sign, but A and SUM differ in
179 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
181 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
183 /* If ARG2 divides ARG1 with zero remainder, carries out the division
184 of type CODE and returns the quotient.
185 Otherwise returns NULL_TREE. */
188 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
193 /* The sign of the division is according to operand two, that
194 does the correct thing for POINTER_PLUS_EXPR where we want
195 a signed division. */
196 uns = TYPE_UNSIGNED (TREE_TYPE (arg2));
197 if (TREE_CODE (TREE_TYPE (arg2)) == INTEGER_TYPE
198 && TYPE_IS_SIZETYPE (TREE_TYPE (arg2)))
201 quo = double_int_divmod (tree_to_double_int (arg1),
202 tree_to_double_int (arg2),
205 if (double_int_zero_p (rem))
206 return build_int_cst_wide (TREE_TYPE (arg1), quo.low, quo.high);
211 /* This is nonzero if we should defer warnings about undefined
212 overflow. This facility exists because these warnings are a
213 special case. The code to estimate loop iterations does not want
214 to issue any warnings, since it works with expressions which do not
215 occur in user code. Various bits of cleanup code call fold(), but
216 only use the result if it has certain characteristics (e.g., is a
217 constant); that code only wants to issue a warning if the result is
220 static int fold_deferring_overflow_warnings;
222 /* If a warning about undefined overflow is deferred, this is the
223 warning. Note that this may cause us to turn two warnings into
224 one, but that is fine since it is sufficient to only give one
225 warning per expression. */
227 static const char* fold_deferred_overflow_warning;
229 /* If a warning about undefined overflow is deferred, this is the
230 level at which the warning should be emitted. */
232 static enum warn_strict_overflow_code fold_deferred_overflow_code;
234 /* Start deferring overflow warnings. We could use a stack here to
235 permit nested calls, but at present it is not necessary. */
238 fold_defer_overflow_warnings (void)
240 ++fold_deferring_overflow_warnings;
243 /* Stop deferring overflow warnings. If there is a pending warning,
244 and ISSUE is true, then issue the warning if appropriate. STMT is
245 the statement with which the warning should be associated (used for
246 location information); STMT may be NULL. CODE is the level of the
247 warning--a warn_strict_overflow_code value. This function will use
248 the smaller of CODE and the deferred code when deciding whether to
249 issue the warning. CODE may be zero to mean to always use the
253 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
258 gcc_assert (fold_deferring_overflow_warnings > 0);
259 --fold_deferring_overflow_warnings;
260 if (fold_deferring_overflow_warnings > 0)
262 if (fold_deferred_overflow_warning != NULL
264 && code < (int) fold_deferred_overflow_code)
265 fold_deferred_overflow_code = (enum warn_strict_overflow_code) code;
269 warnmsg = fold_deferred_overflow_warning;
270 fold_deferred_overflow_warning = NULL;
272 if (!issue || warnmsg == NULL)
275 if (gimple_no_warning_p (stmt))
278 /* Use the smallest code level when deciding to issue the
280 if (code == 0 || code > (int) fold_deferred_overflow_code)
281 code = fold_deferred_overflow_code;
283 if (!issue_strict_overflow_warning (code))
287 locus = input_location;
289 locus = gimple_location (stmt);
290 warning_at (locus, OPT_Wstrict_overflow, "%s", warnmsg);
293 /* Stop deferring overflow warnings, ignoring any deferred
297 fold_undefer_and_ignore_overflow_warnings (void)
299 fold_undefer_overflow_warnings (false, NULL, 0);
302 /* Whether we are deferring overflow warnings. */
305 fold_deferring_overflow_warnings_p (void)
307 return fold_deferring_overflow_warnings > 0;
310 /* This is called when we fold something based on the fact that signed
311 overflow is undefined. */
314 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
316 if (fold_deferring_overflow_warnings > 0)
318 if (fold_deferred_overflow_warning == NULL
319 || wc < fold_deferred_overflow_code)
321 fold_deferred_overflow_warning = gmsgid;
322 fold_deferred_overflow_code = wc;
325 else if (issue_strict_overflow_warning (wc))
326 warning (OPT_Wstrict_overflow, gmsgid);
329 /* Return true if the built-in mathematical function specified by CODE
330 is odd, i.e. -f(x) == f(-x). */
333 negate_mathfn_p (enum built_in_function code)
337 CASE_FLT_FN (BUILT_IN_ASIN):
338 CASE_FLT_FN (BUILT_IN_ASINH):
339 CASE_FLT_FN (BUILT_IN_ATAN):
340 CASE_FLT_FN (BUILT_IN_ATANH):
341 CASE_FLT_FN (BUILT_IN_CASIN):
342 CASE_FLT_FN (BUILT_IN_CASINH):
343 CASE_FLT_FN (BUILT_IN_CATAN):
344 CASE_FLT_FN (BUILT_IN_CATANH):
345 CASE_FLT_FN (BUILT_IN_CBRT):
346 CASE_FLT_FN (BUILT_IN_CPROJ):
347 CASE_FLT_FN (BUILT_IN_CSIN):
348 CASE_FLT_FN (BUILT_IN_CSINH):
349 CASE_FLT_FN (BUILT_IN_CTAN):
350 CASE_FLT_FN (BUILT_IN_CTANH):
351 CASE_FLT_FN (BUILT_IN_ERF):
352 CASE_FLT_FN (BUILT_IN_LLROUND):
353 CASE_FLT_FN (BUILT_IN_LROUND):
354 CASE_FLT_FN (BUILT_IN_ROUND):
355 CASE_FLT_FN (BUILT_IN_SIN):
356 CASE_FLT_FN (BUILT_IN_SINH):
357 CASE_FLT_FN (BUILT_IN_TAN):
358 CASE_FLT_FN (BUILT_IN_TANH):
359 CASE_FLT_FN (BUILT_IN_TRUNC):
362 CASE_FLT_FN (BUILT_IN_LLRINT):
363 CASE_FLT_FN (BUILT_IN_LRINT):
364 CASE_FLT_FN (BUILT_IN_NEARBYINT):
365 CASE_FLT_FN (BUILT_IN_RINT):
366 return !flag_rounding_math;
374 /* Check whether we may negate an integer constant T without causing
378 may_negate_without_overflow_p (const_tree t)
380 unsigned HOST_WIDE_INT val;
384 gcc_assert (TREE_CODE (t) == INTEGER_CST);
386 type = TREE_TYPE (t);
387 if (TYPE_UNSIGNED (type))
390 prec = TYPE_PRECISION (type);
391 if (prec > HOST_BITS_PER_WIDE_INT)
393 if (TREE_INT_CST_LOW (t) != 0)
395 prec -= HOST_BITS_PER_WIDE_INT;
396 val = TREE_INT_CST_HIGH (t);
399 val = TREE_INT_CST_LOW (t);
400 if (prec < HOST_BITS_PER_WIDE_INT)
401 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
402 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
405 /* Determine whether an expression T can be cheaply negated using
406 the function negate_expr without introducing undefined overflow. */
409 negate_expr_p (tree t)
416 type = TREE_TYPE (t);
419 switch (TREE_CODE (t))
422 if (TYPE_OVERFLOW_WRAPS (type))
425 /* Check that -CST will not overflow type. */
426 return may_negate_without_overflow_p (t);
428 return (INTEGRAL_TYPE_P (type)
429 && TYPE_OVERFLOW_WRAPS (type));
436 /* We want to canonicalize to positive real constants. Pretend
437 that only negative ones can be easily negated. */
438 return REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
441 return negate_expr_p (TREE_REALPART (t))
442 && negate_expr_p (TREE_IMAGPART (t));
445 return negate_expr_p (TREE_OPERAND (t, 0))
446 && negate_expr_p (TREE_OPERAND (t, 1));
449 return negate_expr_p (TREE_OPERAND (t, 0));
452 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
453 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
455 /* -(A + B) -> (-B) - A. */
456 if (negate_expr_p (TREE_OPERAND (t, 1))
457 && reorder_operands_p (TREE_OPERAND (t, 0),
458 TREE_OPERAND (t, 1)))
460 /* -(A + B) -> (-A) - B. */
461 return negate_expr_p (TREE_OPERAND (t, 0));
464 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
465 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
466 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
467 && reorder_operands_p (TREE_OPERAND (t, 0),
468 TREE_OPERAND (t, 1));
471 if (TYPE_UNSIGNED (TREE_TYPE (t)))
477 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
478 return negate_expr_p (TREE_OPERAND (t, 1))
479 || negate_expr_p (TREE_OPERAND (t, 0));
487 /* In general we can't negate A / B, because if A is INT_MIN and
488 B is 1, we may turn this into INT_MIN / -1 which is undefined
489 and actually traps on some architectures. But if overflow is
490 undefined, we can negate, because - (INT_MIN / 1) is an
492 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
493 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
495 return negate_expr_p (TREE_OPERAND (t, 1))
496 || negate_expr_p (TREE_OPERAND (t, 0));
499 /* Negate -((double)float) as (double)(-float). */
500 if (TREE_CODE (type) == REAL_TYPE)
502 tree tem = strip_float_extensions (t);
504 return negate_expr_p (tem);
509 /* Negate -f(x) as f(-x). */
510 if (negate_mathfn_p (builtin_mathfn_code (t)))
511 return negate_expr_p (CALL_EXPR_ARG (t, 0));
515 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
516 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
518 tree op1 = TREE_OPERAND (t, 1);
519 if (TREE_INT_CST_HIGH (op1) == 0
520 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
521 == TREE_INT_CST_LOW (op1))
532 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
533 simplification is possible.
534 If negate_expr_p would return true for T, NULL_TREE will never be
538 fold_negate_expr (location_t loc, tree t)
540 tree type = TREE_TYPE (t);
543 switch (TREE_CODE (t))
545 /* Convert - (~A) to A + 1. */
547 if (INTEGRAL_TYPE_P (type))
548 return fold_build2_loc (loc, PLUS_EXPR, type, TREE_OPERAND (t, 0),
549 build_int_cst (type, 1));
553 tem = fold_negate_const (t, type);
554 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
555 || !TYPE_OVERFLOW_TRAPS (type))
560 tem = fold_negate_const (t, type);
561 /* Two's complement FP formats, such as c4x, may overflow. */
562 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
567 tem = fold_negate_const (t, type);
572 tree rpart = negate_expr (TREE_REALPART (t));
573 tree ipart = negate_expr (TREE_IMAGPART (t));
575 if ((TREE_CODE (rpart) == REAL_CST
576 && TREE_CODE (ipart) == REAL_CST)
577 || (TREE_CODE (rpart) == INTEGER_CST
578 && TREE_CODE (ipart) == INTEGER_CST))
579 return build_complex (type, rpart, ipart);
584 if (negate_expr_p (t))
585 return fold_build2_loc (loc, COMPLEX_EXPR, type,
586 fold_negate_expr (loc, TREE_OPERAND (t, 0)),
587 fold_negate_expr (loc, TREE_OPERAND (t, 1)));
591 if (negate_expr_p (t))
592 return fold_build1_loc (loc, CONJ_EXPR, type,
593 fold_negate_expr (loc, TREE_OPERAND (t, 0)));
597 return TREE_OPERAND (t, 0);
600 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
601 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
603 /* -(A + B) -> (-B) - A. */
604 if (negate_expr_p (TREE_OPERAND (t, 1))
605 && reorder_operands_p (TREE_OPERAND (t, 0),
606 TREE_OPERAND (t, 1)))
608 tem = negate_expr (TREE_OPERAND (t, 1));
609 return fold_build2_loc (loc, MINUS_EXPR, type,
610 tem, TREE_OPERAND (t, 0));
613 /* -(A + B) -> (-A) - B. */
614 if (negate_expr_p (TREE_OPERAND (t, 0)))
616 tem = negate_expr (TREE_OPERAND (t, 0));
617 return fold_build2_loc (loc, MINUS_EXPR, type,
618 tem, TREE_OPERAND (t, 1));
624 /* - (A - B) -> B - A */
625 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
626 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
627 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
628 return fold_build2_loc (loc, MINUS_EXPR, type,
629 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
633 if (TYPE_UNSIGNED (type))
639 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
641 tem = TREE_OPERAND (t, 1);
642 if (negate_expr_p (tem))
643 return fold_build2_loc (loc, TREE_CODE (t), type,
644 TREE_OPERAND (t, 0), negate_expr (tem));
645 tem = TREE_OPERAND (t, 0);
646 if (negate_expr_p (tem))
647 return fold_build2_loc (loc, TREE_CODE (t), type,
648 negate_expr (tem), TREE_OPERAND (t, 1));
657 /* In general we can't negate A / B, because if A is INT_MIN and
658 B is 1, we may turn this into INT_MIN / -1 which is undefined
659 and actually traps on some architectures. But if overflow is
660 undefined, we can negate, because - (INT_MIN / 1) is an
662 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
664 const char * const warnmsg = G_("assuming signed overflow does not "
665 "occur when negating a division");
666 tem = TREE_OPERAND (t, 1);
667 if (negate_expr_p (tem))
669 if (INTEGRAL_TYPE_P (type)
670 && (TREE_CODE (tem) != INTEGER_CST
671 || integer_onep (tem)))
672 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
673 return fold_build2_loc (loc, TREE_CODE (t), type,
674 TREE_OPERAND (t, 0), negate_expr (tem));
676 tem = TREE_OPERAND (t, 0);
677 if (negate_expr_p (tem))
679 if (INTEGRAL_TYPE_P (type)
680 && (TREE_CODE (tem) != INTEGER_CST
681 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
682 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
683 return fold_build2_loc (loc, TREE_CODE (t), type,
684 negate_expr (tem), TREE_OPERAND (t, 1));
690 /* Convert -((double)float) into (double)(-float). */
691 if (TREE_CODE (type) == REAL_TYPE)
693 tem = strip_float_extensions (t);
694 if (tem != t && negate_expr_p (tem))
695 return fold_convert_loc (loc, type, negate_expr (tem));
700 /* Negate -f(x) as f(-x). */
701 if (negate_mathfn_p (builtin_mathfn_code (t))
702 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
706 fndecl = get_callee_fndecl (t);
707 arg = negate_expr (CALL_EXPR_ARG (t, 0));
708 return build_call_expr_loc (loc, fndecl, 1, arg);
713 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
714 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
716 tree op1 = TREE_OPERAND (t, 1);
717 if (TREE_INT_CST_HIGH (op1) == 0
718 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
719 == TREE_INT_CST_LOW (op1))
721 tree ntype = TYPE_UNSIGNED (type)
722 ? signed_type_for (type)
723 : unsigned_type_for (type);
724 tree temp = fold_convert_loc (loc, ntype, TREE_OPERAND (t, 0));
725 temp = fold_build2_loc (loc, RSHIFT_EXPR, ntype, temp, op1);
726 return fold_convert_loc (loc, type, temp);
738 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
739 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
751 loc = EXPR_LOCATION (t);
752 type = TREE_TYPE (t);
755 tem = fold_negate_expr (loc, t);
757 tem = build1_loc (loc, NEGATE_EXPR, TREE_TYPE (t), t);
758 return fold_convert_loc (loc, type, tem);
761 /* Split a tree IN into a constant, literal and variable parts that could be
762 combined with CODE to make IN. "constant" means an expression with
763 TREE_CONSTANT but that isn't an actual constant. CODE must be a
764 commutative arithmetic operation. Store the constant part into *CONP,
765 the literal in *LITP and return the variable part. If a part isn't
766 present, set it to null. If the tree does not decompose in this way,
767 return the entire tree as the variable part and the other parts as null.
769 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
770 case, we negate an operand that was subtracted. Except if it is a
771 literal for which we use *MINUS_LITP instead.
773 If NEGATE_P is true, we are negating all of IN, again except a literal
774 for which we use *MINUS_LITP instead.
776 If IN is itself a literal or constant, return it as appropriate.
778 Note that we do not guarantee that any of the three values will be the
779 same type as IN, but they will have the same signedness and mode. */
782 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
783 tree *minus_litp, int negate_p)
791 /* Strip any conversions that don't change the machine mode or signedness. */
792 STRIP_SIGN_NOPS (in);
794 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
795 || TREE_CODE (in) == FIXED_CST)
797 else if (TREE_CODE (in) == code
798 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
799 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
800 /* We can associate addition and subtraction together (even
801 though the C standard doesn't say so) for integers because
802 the value is not affected. For reals, the value might be
803 affected, so we can't. */
804 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
805 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
807 tree op0 = TREE_OPERAND (in, 0);
808 tree op1 = TREE_OPERAND (in, 1);
809 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
810 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
812 /* First see if either of the operands is a literal, then a constant. */
813 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
814 || TREE_CODE (op0) == FIXED_CST)
815 *litp = op0, op0 = 0;
816 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
817 || TREE_CODE (op1) == FIXED_CST)
818 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
820 if (op0 != 0 && TREE_CONSTANT (op0))
821 *conp = op0, op0 = 0;
822 else if (op1 != 0 && TREE_CONSTANT (op1))
823 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
825 /* If we haven't dealt with either operand, this is not a case we can
826 decompose. Otherwise, VAR is either of the ones remaining, if any. */
827 if (op0 != 0 && op1 != 0)
832 var = op1, neg_var_p = neg1_p;
834 /* Now do any needed negations. */
836 *minus_litp = *litp, *litp = 0;
838 *conp = negate_expr (*conp);
840 var = negate_expr (var);
842 else if (TREE_CONSTANT (in))
850 *minus_litp = *litp, *litp = 0;
851 else if (*minus_litp)
852 *litp = *minus_litp, *minus_litp = 0;
853 *conp = negate_expr (*conp);
854 var = negate_expr (var);
860 /* Re-associate trees split by the above function. T1 and T2 are
861 either expressions to associate or null. Return the new
862 expression, if any. LOC is the location of the new expression. If
863 we build an operation, do it in TYPE and with CODE. */
866 associate_trees (location_t loc, tree t1, tree t2, enum tree_code code, tree type)
873 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
874 try to fold this since we will have infinite recursion. But do
875 deal with any NEGATE_EXPRs. */
876 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
877 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
879 if (code == PLUS_EXPR)
881 if (TREE_CODE (t1) == NEGATE_EXPR)
882 return build2_loc (loc, MINUS_EXPR, type,
883 fold_convert_loc (loc, type, t2),
884 fold_convert_loc (loc, type,
885 TREE_OPERAND (t1, 0)));
886 else if (TREE_CODE (t2) == NEGATE_EXPR)
887 return build2_loc (loc, MINUS_EXPR, type,
888 fold_convert_loc (loc, type, t1),
889 fold_convert_loc (loc, type,
890 TREE_OPERAND (t2, 0)));
891 else if (integer_zerop (t2))
892 return fold_convert_loc (loc, type, t1);
894 else if (code == MINUS_EXPR)
896 if (integer_zerop (t2))
897 return fold_convert_loc (loc, type, t1);
900 return build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
901 fold_convert_loc (loc, type, t2));
904 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
905 fold_convert_loc (loc, type, t2));
908 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
909 for use in int_const_binop, size_binop and size_diffop. */
912 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
914 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
916 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
931 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
932 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
933 && TYPE_MODE (type1) == TYPE_MODE (type2);
937 /* Combine two integer constants ARG1 and ARG2 under operation CODE
938 to produce a new constant. Return NULL_TREE if we don't know how
939 to evaluate CODE at compile-time. */
942 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2)
944 double_int op1, op2, res, tmp;
946 tree type = TREE_TYPE (arg1);
947 bool uns = TYPE_UNSIGNED (type);
949 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
950 bool overflow = false;
952 op1 = tree_to_double_int (arg1);
953 op2 = tree_to_double_int (arg2);
958 res = double_int_ior (op1, op2);
962 res = double_int_xor (op1, op2);
966 res = double_int_and (op1, op2);
970 res = double_int_rshift (op1, double_int_to_shwi (op2),
971 TYPE_PRECISION (type), !uns);
975 /* It's unclear from the C standard whether shifts can overflow.
976 The following code ignores overflow; perhaps a C standard
977 interpretation ruling is needed. */
978 res = double_int_lshift (op1, double_int_to_shwi (op2),
979 TYPE_PRECISION (type), !uns);
983 res = double_int_rrotate (op1, double_int_to_shwi (op2),
984 TYPE_PRECISION (type));
988 res = double_int_lrotate (op1, double_int_to_shwi (op2),
989 TYPE_PRECISION (type));
993 overflow = add_double (op1.low, op1.high, op2.low, op2.high,
994 &res.low, &res.high);
998 neg_double (op2.low, op2.high, &res.low, &res.high);
999 add_double (op1.low, op1.high, res.low, res.high,
1000 &res.low, &res.high);
1001 overflow = OVERFLOW_SUM_SIGN (res.high, op2.high, op1.high);
1005 overflow = mul_double (op1.low, op1.high, op2.low, op2.high,
1006 &res.low, &res.high);
1009 case TRUNC_DIV_EXPR:
1010 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1011 case EXACT_DIV_EXPR:
1012 /* This is a shortcut for a common special case. */
1013 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
1014 && !TREE_OVERFLOW (arg1)
1015 && !TREE_OVERFLOW (arg2)
1016 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
1018 if (code == CEIL_DIV_EXPR)
1019 op1.low += op2.low - 1;
1021 res.low = op1.low / op2.low, res.high = 0;
1025 /* ... fall through ... */
1027 case ROUND_DIV_EXPR:
1028 if (double_int_zero_p (op2))
1030 if (double_int_one_p (op2))
1035 if (double_int_equal_p (op1, op2)
1036 && ! double_int_zero_p (op1))
1038 res = double_int_one;
1041 overflow = div_and_round_double (code, uns,
1042 op1.low, op1.high, op2.low, op2.high,
1043 &res.low, &res.high,
1044 &tmp.low, &tmp.high);
1047 case TRUNC_MOD_EXPR:
1048 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1049 /* This is a shortcut for a common special case. */
1050 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
1051 && !TREE_OVERFLOW (arg1)
1052 && !TREE_OVERFLOW (arg2)
1053 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
1055 if (code == CEIL_MOD_EXPR)
1056 op1.low += op2.low - 1;
1057 res.low = op1.low % op2.low, res.high = 0;
1061 /* ... fall through ... */
1063 case ROUND_MOD_EXPR:
1064 if (double_int_zero_p (op2))
1066 overflow = div_and_round_double (code, uns,
1067 op1.low, op1.high, op2.low, op2.high,
1068 &tmp.low, &tmp.high,
1069 &res.low, &res.high);
1073 res = double_int_min (op1, op2, uns);
1077 res = double_int_max (op1, op2, uns);
1084 t = force_fit_type_double (TREE_TYPE (arg1), res, 1,
1085 ((!uns || is_sizetype) && overflow)
1086 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1091 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1092 constant. We assume ARG1 and ARG2 have the same data type, or at least
1093 are the same kind of constant and the same machine mode. Return zero if
1094 combining the constants is not allowed in the current operating mode. */
1097 const_binop (enum tree_code code, tree arg1, tree arg2)
1099 /* Sanity check for the recursive cases. */
1106 if (TREE_CODE (arg1) == INTEGER_CST)
1107 return int_const_binop (code, arg1, arg2);
1109 if (TREE_CODE (arg1) == REAL_CST)
1111 enum machine_mode mode;
1114 REAL_VALUE_TYPE value;
1115 REAL_VALUE_TYPE result;
1119 /* The following codes are handled by real_arithmetic. */
1134 d1 = TREE_REAL_CST (arg1);
1135 d2 = TREE_REAL_CST (arg2);
1137 type = TREE_TYPE (arg1);
1138 mode = TYPE_MODE (type);
1140 /* Don't perform operation if we honor signaling NaNs and
1141 either operand is a NaN. */
1142 if (HONOR_SNANS (mode)
1143 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1146 /* Don't perform operation if it would raise a division
1147 by zero exception. */
1148 if (code == RDIV_EXPR
1149 && REAL_VALUES_EQUAL (d2, dconst0)
1150 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1153 /* If either operand is a NaN, just return it. Otherwise, set up
1154 for floating-point trap; we return an overflow. */
1155 if (REAL_VALUE_ISNAN (d1))
1157 else if (REAL_VALUE_ISNAN (d2))
1160 inexact = real_arithmetic (&value, code, &d1, &d2);
1161 real_convert (&result, mode, &value);
1163 /* Don't constant fold this floating point operation if
1164 the result has overflowed and flag_trapping_math. */
1165 if (flag_trapping_math
1166 && MODE_HAS_INFINITIES (mode)
1167 && REAL_VALUE_ISINF (result)
1168 && !REAL_VALUE_ISINF (d1)
1169 && !REAL_VALUE_ISINF (d2))
1172 /* Don't constant fold this floating point operation if the
1173 result may dependent upon the run-time rounding mode and
1174 flag_rounding_math is set, or if GCC's software emulation
1175 is unable to accurately represent the result. */
1176 if ((flag_rounding_math
1177 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1178 && (inexact || !real_identical (&result, &value)))
1181 t = build_real (type, result);
1183 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1187 if (TREE_CODE (arg1) == FIXED_CST)
1189 FIXED_VALUE_TYPE f1;
1190 FIXED_VALUE_TYPE f2;
1191 FIXED_VALUE_TYPE result;
1196 /* The following codes are handled by fixed_arithmetic. */
1202 case TRUNC_DIV_EXPR:
1203 f2 = TREE_FIXED_CST (arg2);
1208 f2.data.high = TREE_INT_CST_HIGH (arg2);
1209 f2.data.low = TREE_INT_CST_LOW (arg2);
1217 f1 = TREE_FIXED_CST (arg1);
1218 type = TREE_TYPE (arg1);
1219 sat_p = TYPE_SATURATING (type);
1220 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1221 t = build_fixed (type, result);
1222 /* Propagate overflow flags. */
1223 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1224 TREE_OVERFLOW (t) = 1;
1228 if (TREE_CODE (arg1) == COMPLEX_CST)
1230 tree type = TREE_TYPE (arg1);
1231 tree r1 = TREE_REALPART (arg1);
1232 tree i1 = TREE_IMAGPART (arg1);
1233 tree r2 = TREE_REALPART (arg2);
1234 tree i2 = TREE_IMAGPART (arg2);
1241 real = const_binop (code, r1, r2);
1242 imag = const_binop (code, i1, i2);
1246 if (COMPLEX_FLOAT_TYPE_P (type))
1247 return do_mpc_arg2 (arg1, arg2, type,
1248 /* do_nonfinite= */ folding_initializer,
1251 real = const_binop (MINUS_EXPR,
1252 const_binop (MULT_EXPR, r1, r2),
1253 const_binop (MULT_EXPR, i1, i2));
1254 imag = const_binop (PLUS_EXPR,
1255 const_binop (MULT_EXPR, r1, i2),
1256 const_binop (MULT_EXPR, i1, r2));
1260 if (COMPLEX_FLOAT_TYPE_P (type))
1261 return do_mpc_arg2 (arg1, arg2, type,
1262 /* do_nonfinite= */ folding_initializer,
1265 case TRUNC_DIV_EXPR:
1267 case FLOOR_DIV_EXPR:
1268 case ROUND_DIV_EXPR:
1269 if (flag_complex_method == 0)
1271 /* Keep this algorithm in sync with
1272 tree-complex.c:expand_complex_div_straight().
1274 Expand complex division to scalars, straightforward algorithm.
1275 a / b = ((ar*br + ai*bi)/t) + i((ai*br - ar*bi)/t)
1279 = const_binop (PLUS_EXPR,
1280 const_binop (MULT_EXPR, r2, r2),
1281 const_binop (MULT_EXPR, i2, i2));
1283 = const_binop (PLUS_EXPR,
1284 const_binop (MULT_EXPR, r1, r2),
1285 const_binop (MULT_EXPR, i1, i2));
1287 = const_binop (MINUS_EXPR,
1288 const_binop (MULT_EXPR, i1, r2),
1289 const_binop (MULT_EXPR, r1, i2));
1291 real = const_binop (code, t1, magsquared);
1292 imag = const_binop (code, t2, magsquared);
1296 /* Keep this algorithm in sync with
1297 tree-complex.c:expand_complex_div_wide().
1299 Expand complex division to scalars, modified algorithm to minimize
1300 overflow with wide input ranges. */
1301 tree compare = fold_build2 (LT_EXPR, boolean_type_node,
1302 fold_abs_const (r2, TREE_TYPE (type)),
1303 fold_abs_const (i2, TREE_TYPE (type)));
1305 if (integer_nonzerop (compare))
1307 /* In the TRUE branch, we compute
1309 div = (br * ratio) + bi;
1310 tr = (ar * ratio) + ai;
1311 ti = (ai * ratio) - ar;
1314 tree ratio = const_binop (code, r2, i2);
1315 tree div = const_binop (PLUS_EXPR, i2,
1316 const_binop (MULT_EXPR, r2, ratio));
1317 real = const_binop (MULT_EXPR, r1, ratio);
1318 real = const_binop (PLUS_EXPR, real, i1);
1319 real = const_binop (code, real, div);
1321 imag = const_binop (MULT_EXPR, i1, ratio);
1322 imag = const_binop (MINUS_EXPR, imag, r1);
1323 imag = const_binop (code, imag, div);
1327 /* In the FALSE branch, we compute
1329 divisor = (d * ratio) + c;
1330 tr = (b * ratio) + a;
1331 ti = b - (a * ratio);
1334 tree ratio = const_binop (code, i2, r2);
1335 tree div = const_binop (PLUS_EXPR, r2,
1336 const_binop (MULT_EXPR, i2, ratio));
1338 real = const_binop (MULT_EXPR, i1, ratio);
1339 real = const_binop (PLUS_EXPR, real, r1);
1340 real = const_binop (code, real, div);
1342 imag = const_binop (MULT_EXPR, r1, ratio);
1343 imag = const_binop (MINUS_EXPR, i1, imag);
1344 imag = const_binop (code, imag, div);
1354 return build_complex (type, real, imag);
1357 if (TREE_CODE (arg1) == VECTOR_CST)
1359 tree type = TREE_TYPE(arg1);
1360 int count = TYPE_VECTOR_SUBPARTS (type), i;
1361 tree elements1, elements2, list = NULL_TREE;
1363 if(TREE_CODE(arg2) != VECTOR_CST)
1366 elements1 = TREE_VECTOR_CST_ELTS (arg1);
1367 elements2 = TREE_VECTOR_CST_ELTS (arg2);
1369 for (i = 0; i < count; i++)
1371 tree elem1, elem2, elem;
1373 /* The trailing elements can be empty and should be treated as 0 */
1375 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1378 elem1 = TREE_VALUE(elements1);
1379 elements1 = TREE_CHAIN (elements1);
1383 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1386 elem2 = TREE_VALUE(elements2);
1387 elements2 = TREE_CHAIN (elements2);
1390 elem = const_binop (code, elem1, elem2);
1392 /* It is possible that const_binop cannot handle the given
1393 code and return NULL_TREE */
1394 if(elem == NULL_TREE)
1397 list = tree_cons (NULL_TREE, elem, list);
1399 return build_vector(type, nreverse(list));
1404 /* Create a size type INT_CST node with NUMBER sign extended. KIND
1405 indicates which particular sizetype to create. */
1408 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
1410 return build_int_cst (sizetype_tab[(int) kind], number);
1413 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
1414 is a tree code. The type of the result is taken from the operands.
1415 Both must be equivalent integer types, ala int_binop_types_match_p.
1416 If the operands are constant, so is the result. */
1419 size_binop_loc (location_t loc, enum tree_code code, tree arg0, tree arg1)
1421 tree type = TREE_TYPE (arg0);
1423 if (arg0 == error_mark_node || arg1 == error_mark_node)
1424 return error_mark_node;
1426 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
1429 /* Handle the special case of two integer constants faster. */
1430 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
1432 /* And some specific cases even faster than that. */
1433 if (code == PLUS_EXPR)
1435 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
1437 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1440 else if (code == MINUS_EXPR)
1442 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1445 else if (code == MULT_EXPR)
1447 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
1451 /* Handle general case of two integer constants. */
1452 return int_const_binop (code, arg0, arg1);
1455 return fold_build2_loc (loc, code, type, arg0, arg1);
1458 /* Given two values, either both of sizetype or both of bitsizetype,
1459 compute the difference between the two values. Return the value
1460 in signed type corresponding to the type of the operands. */
1463 size_diffop_loc (location_t loc, tree arg0, tree arg1)
1465 tree type = TREE_TYPE (arg0);
1468 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
1471 /* If the type is already signed, just do the simple thing. */
1472 if (!TYPE_UNSIGNED (type))
1473 return size_binop_loc (loc, MINUS_EXPR, arg0, arg1);
1475 if (type == sizetype)
1477 else if (type == bitsizetype)
1478 ctype = sbitsizetype;
1480 ctype = signed_type_for (type);
1482 /* If either operand is not a constant, do the conversions to the signed
1483 type and subtract. The hardware will do the right thing with any
1484 overflow in the subtraction. */
1485 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
1486 return size_binop_loc (loc, MINUS_EXPR,
1487 fold_convert_loc (loc, ctype, arg0),
1488 fold_convert_loc (loc, ctype, arg1));
1490 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
1491 Otherwise, subtract the other way, convert to CTYPE (we know that can't
1492 overflow) and negate (which can't either). Special-case a result
1493 of zero while we're here. */
1494 if (tree_int_cst_equal (arg0, arg1))
1495 return build_int_cst (ctype, 0);
1496 else if (tree_int_cst_lt (arg1, arg0))
1497 return fold_convert_loc (loc, ctype,
1498 size_binop_loc (loc, MINUS_EXPR, arg0, arg1));
1500 return size_binop_loc (loc, MINUS_EXPR, build_int_cst (ctype, 0),
1501 fold_convert_loc (loc, ctype,
1502 size_binop_loc (loc,
1507 /* A subroutine of fold_convert_const handling conversions of an
1508 INTEGER_CST to another integer type. */
1511 fold_convert_const_int_from_int (tree type, const_tree arg1)
1515 /* Given an integer constant, make new constant with new type,
1516 appropriately sign-extended or truncated. */
1517 t = force_fit_type_double (type, tree_to_double_int (arg1),
1518 !POINTER_TYPE_P (TREE_TYPE (arg1)),
1519 (TREE_INT_CST_HIGH (arg1) < 0
1520 && (TYPE_UNSIGNED (type)
1521 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1522 | TREE_OVERFLOW (arg1));
1527 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1528 to an integer type. */
1531 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
1536 /* The following code implements the floating point to integer
1537 conversion rules required by the Java Language Specification,
1538 that IEEE NaNs are mapped to zero and values that overflow
1539 the target precision saturate, i.e. values greater than
1540 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
1541 are mapped to INT_MIN. These semantics are allowed by the
1542 C and C++ standards that simply state that the behavior of
1543 FP-to-integer conversion is unspecified upon overflow. */
1547 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
1551 case FIX_TRUNC_EXPR:
1552 real_trunc (&r, VOIDmode, &x);
1559 /* If R is NaN, return zero and show we have an overflow. */
1560 if (REAL_VALUE_ISNAN (r))
1563 val = double_int_zero;
1566 /* See if R is less than the lower bound or greater than the
1571 tree lt = TYPE_MIN_VALUE (type);
1572 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
1573 if (REAL_VALUES_LESS (r, l))
1576 val = tree_to_double_int (lt);
1582 tree ut = TYPE_MAX_VALUE (type);
1585 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
1586 if (REAL_VALUES_LESS (u, r))
1589 val = tree_to_double_int (ut);
1595 real_to_integer2 ((HOST_WIDE_INT *) &val.low, &val.high, &r);
1597 t = force_fit_type_double (type, val, -1, overflow | TREE_OVERFLOW (arg1));
1601 /* A subroutine of fold_convert_const handling conversions of a
1602 FIXED_CST to an integer type. */
1605 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
1608 double_int temp, temp_trunc;
1611 /* Right shift FIXED_CST to temp by fbit. */
1612 temp = TREE_FIXED_CST (arg1).data;
1613 mode = TREE_FIXED_CST (arg1).mode;
1614 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
1616 temp = double_int_rshift (temp, GET_MODE_FBIT (mode),
1617 HOST_BITS_PER_DOUBLE_INT,
1618 SIGNED_FIXED_POINT_MODE_P (mode));
1620 /* Left shift temp to temp_trunc by fbit. */
1621 temp_trunc = double_int_lshift (temp, GET_MODE_FBIT (mode),
1622 HOST_BITS_PER_DOUBLE_INT,
1623 SIGNED_FIXED_POINT_MODE_P (mode));
1627 temp = double_int_zero;
1628 temp_trunc = double_int_zero;
1631 /* If FIXED_CST is negative, we need to round the value toward 0.
1632 By checking if the fractional bits are not zero to add 1 to temp. */
1633 if (SIGNED_FIXED_POINT_MODE_P (mode)
1634 && double_int_negative_p (temp_trunc)
1635 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
1636 temp = double_int_add (temp, double_int_one);
1638 /* Given a fixed-point constant, make new constant with new type,
1639 appropriately sign-extended or truncated. */
1640 t = force_fit_type_double (type, temp, -1,
1641 (double_int_negative_p (temp)
1642 && (TYPE_UNSIGNED (type)
1643 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1644 | TREE_OVERFLOW (arg1));
1649 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1650 to another floating point type. */
1653 fold_convert_const_real_from_real (tree type, const_tree arg1)
1655 REAL_VALUE_TYPE value;
1658 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
1659 t = build_real (type, value);
1661 /* If converting an infinity or NAN to a representation that doesn't
1662 have one, set the overflow bit so that we can produce some kind of
1663 error message at the appropriate point if necessary. It's not the
1664 most user-friendly message, but it's better than nothing. */
1665 if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1))
1666 && !MODE_HAS_INFINITIES (TYPE_MODE (type)))
1667 TREE_OVERFLOW (t) = 1;
1668 else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
1669 && !MODE_HAS_NANS (TYPE_MODE (type)))
1670 TREE_OVERFLOW (t) = 1;
1671 /* Regular overflow, conversion produced an infinity in a mode that
1672 can't represent them. */
1673 else if (!MODE_HAS_INFINITIES (TYPE_MODE (type))
1674 && REAL_VALUE_ISINF (value)
1675 && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1)))
1676 TREE_OVERFLOW (t) = 1;
1678 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1682 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1683 to a floating point type. */
1686 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
1688 REAL_VALUE_TYPE value;
1691 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
1692 t = build_real (type, value);
1694 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1698 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1699 to another fixed-point type. */
1702 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
1704 FIXED_VALUE_TYPE value;
1708 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
1709 TYPE_SATURATING (type));
1710 t = build_fixed (type, value);
1712 /* Propagate overflow flags. */
1713 if (overflow_p | TREE_OVERFLOW (arg1))
1714 TREE_OVERFLOW (t) = 1;
1718 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
1719 to a fixed-point type. */
1722 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
1724 FIXED_VALUE_TYPE value;
1728 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
1729 TREE_INT_CST (arg1),
1730 TYPE_UNSIGNED (TREE_TYPE (arg1)),
1731 TYPE_SATURATING (type));
1732 t = build_fixed (type, value);
1734 /* Propagate overflow flags. */
1735 if (overflow_p | TREE_OVERFLOW (arg1))
1736 TREE_OVERFLOW (t) = 1;
1740 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1741 to a fixed-point type. */
1744 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
1746 FIXED_VALUE_TYPE value;
1750 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
1751 &TREE_REAL_CST (arg1),
1752 TYPE_SATURATING (type));
1753 t = build_fixed (type, value);
1755 /* Propagate overflow flags. */
1756 if (overflow_p | TREE_OVERFLOW (arg1))
1757 TREE_OVERFLOW (t) = 1;
1761 /* Attempt to fold type conversion operation CODE of expression ARG1 to
1762 type TYPE. If no simplification can be done return NULL_TREE. */
1765 fold_convert_const (enum tree_code code, tree type, tree arg1)
1767 if (TREE_TYPE (arg1) == type)
1770 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
1771 || TREE_CODE (type) == OFFSET_TYPE)
1773 if (TREE_CODE (arg1) == INTEGER_CST)
1774 return fold_convert_const_int_from_int (type, arg1);
1775 else if (TREE_CODE (arg1) == REAL_CST)
1776 return fold_convert_const_int_from_real (code, type, arg1);
1777 else if (TREE_CODE (arg1) == FIXED_CST)
1778 return fold_convert_const_int_from_fixed (type, arg1);
1780 else if (TREE_CODE (type) == REAL_TYPE)
1782 if (TREE_CODE (arg1) == INTEGER_CST)
1783 return build_real_from_int_cst (type, arg1);
1784 else if (TREE_CODE (arg1) == REAL_CST)
1785 return fold_convert_const_real_from_real (type, arg1);
1786 else if (TREE_CODE (arg1) == FIXED_CST)
1787 return fold_convert_const_real_from_fixed (type, arg1);
1789 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
1791 if (TREE_CODE (arg1) == FIXED_CST)
1792 return fold_convert_const_fixed_from_fixed (type, arg1);
1793 else if (TREE_CODE (arg1) == INTEGER_CST)
1794 return fold_convert_const_fixed_from_int (type, arg1);
1795 else if (TREE_CODE (arg1) == REAL_CST)
1796 return fold_convert_const_fixed_from_real (type, arg1);
1801 /* Construct a vector of zero elements of vector type TYPE. */
1804 build_zero_vector (tree type)
1808 t = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1809 return build_vector_from_val (type, t);
1812 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
1815 fold_convertible_p (const_tree type, const_tree arg)
1817 tree orig = TREE_TYPE (arg);
1822 if (TREE_CODE (arg) == ERROR_MARK
1823 || TREE_CODE (type) == ERROR_MARK
1824 || TREE_CODE (orig) == ERROR_MARK)
1827 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
1830 switch (TREE_CODE (type))
1832 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1833 case POINTER_TYPE: case REFERENCE_TYPE:
1835 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1836 || TREE_CODE (orig) == OFFSET_TYPE)
1838 return (TREE_CODE (orig) == VECTOR_TYPE
1839 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1842 case FIXED_POINT_TYPE:
1846 return TREE_CODE (type) == TREE_CODE (orig);
1853 /* Convert expression ARG to type TYPE. Used by the middle-end for
1854 simple conversions in preference to calling the front-end's convert. */
1857 fold_convert_loc (location_t loc, tree type, tree arg)
1859 tree orig = TREE_TYPE (arg);
1865 if (TREE_CODE (arg) == ERROR_MARK
1866 || TREE_CODE (type) == ERROR_MARK
1867 || TREE_CODE (orig) == ERROR_MARK)
1868 return error_mark_node;
1870 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
1871 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1873 switch (TREE_CODE (type))
1876 case REFERENCE_TYPE:
1877 /* Handle conversions between pointers to different address spaces. */
1878 if (POINTER_TYPE_P (orig)
1879 && (TYPE_ADDR_SPACE (TREE_TYPE (type))
1880 != TYPE_ADDR_SPACE (TREE_TYPE (orig))))
1881 return fold_build1_loc (loc, ADDR_SPACE_CONVERT_EXPR, type, arg);
1884 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1886 if (TREE_CODE (arg) == INTEGER_CST)
1888 tem = fold_convert_const (NOP_EXPR, type, arg);
1889 if (tem != NULL_TREE)
1892 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1893 || TREE_CODE (orig) == OFFSET_TYPE)
1894 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1895 if (TREE_CODE (orig) == COMPLEX_TYPE)
1896 return fold_convert_loc (loc, type,
1897 fold_build1_loc (loc, REALPART_EXPR,
1898 TREE_TYPE (orig), arg));
1899 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
1900 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1901 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1904 if (TREE_CODE (arg) == INTEGER_CST)
1906 tem = fold_convert_const (FLOAT_EXPR, type, arg);
1907 if (tem != NULL_TREE)
1910 else if (TREE_CODE (arg) == REAL_CST)
1912 tem = fold_convert_const (NOP_EXPR, type, arg);
1913 if (tem != NULL_TREE)
1916 else if (TREE_CODE (arg) == FIXED_CST)
1918 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1919 if (tem != NULL_TREE)
1923 switch (TREE_CODE (orig))
1926 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1927 case POINTER_TYPE: case REFERENCE_TYPE:
1928 return fold_build1_loc (loc, FLOAT_EXPR, type, arg);
1931 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1933 case FIXED_POINT_TYPE:
1934 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1937 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1938 return fold_convert_loc (loc, type, tem);
1944 case FIXED_POINT_TYPE:
1945 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
1946 || TREE_CODE (arg) == REAL_CST)
1948 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1949 if (tem != NULL_TREE)
1950 goto fold_convert_exit;
1953 switch (TREE_CODE (orig))
1955 case FIXED_POINT_TYPE:
1960 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1963 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1964 return fold_convert_loc (loc, type, tem);
1971 switch (TREE_CODE (orig))
1974 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1975 case POINTER_TYPE: case REFERENCE_TYPE:
1977 case FIXED_POINT_TYPE:
1978 return fold_build2_loc (loc, COMPLEX_EXPR, type,
1979 fold_convert_loc (loc, TREE_TYPE (type), arg),
1980 fold_convert_loc (loc, TREE_TYPE (type),
1981 integer_zero_node));
1986 if (TREE_CODE (arg) == COMPLEX_EXPR)
1988 rpart = fold_convert_loc (loc, TREE_TYPE (type),
1989 TREE_OPERAND (arg, 0));
1990 ipart = fold_convert_loc (loc, TREE_TYPE (type),
1991 TREE_OPERAND (arg, 1));
1992 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
1995 arg = save_expr (arg);
1996 rpart = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1997 ipart = fold_build1_loc (loc, IMAGPART_EXPR, TREE_TYPE (orig), arg);
1998 rpart = fold_convert_loc (loc, TREE_TYPE (type), rpart);
1999 ipart = fold_convert_loc (loc, TREE_TYPE (type), ipart);
2000 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2008 if (integer_zerop (arg))
2009 return build_zero_vector (type);
2010 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2011 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2012 || TREE_CODE (orig) == VECTOR_TYPE);
2013 return fold_build1_loc (loc, VIEW_CONVERT_EXPR, type, arg);
2016 tem = fold_ignored_result (arg);
2017 return fold_build1_loc (loc, NOP_EXPR, type, tem);
2023 protected_set_expr_location_unshare (tem, loc);
2027 /* Return false if expr can be assumed not to be an lvalue, true
2031 maybe_lvalue_p (const_tree x)
2033 /* We only need to wrap lvalue tree codes. */
2034 switch (TREE_CODE (x))
2047 case ARRAY_RANGE_REF:
2053 case PREINCREMENT_EXPR:
2054 case PREDECREMENT_EXPR:
2056 case TRY_CATCH_EXPR:
2057 case WITH_CLEANUP_EXPR:
2066 /* Assume the worst for front-end tree codes. */
2067 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2075 /* Return an expr equal to X but certainly not valid as an lvalue. */
2078 non_lvalue_loc (location_t loc, tree x)
2080 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2085 if (! maybe_lvalue_p (x))
2087 return build1_loc (loc, NON_LVALUE_EXPR, TREE_TYPE (x), x);
2090 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2091 Zero means allow extended lvalues. */
2093 int pedantic_lvalues;
2095 /* When pedantic, return an expr equal to X but certainly not valid as a
2096 pedantic lvalue. Otherwise, return X. */
2099 pedantic_non_lvalue_loc (location_t loc, tree x)
2101 if (pedantic_lvalues)
2102 return non_lvalue_loc (loc, x);
2104 return protected_set_expr_location_unshare (x, loc);
2107 /* Given a tree comparison code, return the code that is the logical inverse
2108 of the given code. It is not safe to do this for floating-point
2109 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2110 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2113 invert_tree_comparison (enum tree_code code, bool honor_nans)
2115 if (honor_nans && flag_trapping_math)
2125 return honor_nans ? UNLE_EXPR : LE_EXPR;
2127 return honor_nans ? UNLT_EXPR : LT_EXPR;
2129 return honor_nans ? UNGE_EXPR : GE_EXPR;
2131 return honor_nans ? UNGT_EXPR : GT_EXPR;
2145 return UNORDERED_EXPR;
2146 case UNORDERED_EXPR:
2147 return ORDERED_EXPR;
2153 /* Similar, but return the comparison that results if the operands are
2154 swapped. This is safe for floating-point. */
2157 swap_tree_comparison (enum tree_code code)
2164 case UNORDERED_EXPR:
2190 /* Convert a comparison tree code from an enum tree_code representation
2191 into a compcode bit-based encoding. This function is the inverse of
2192 compcode_to_comparison. */
2194 static enum comparison_code
2195 comparison_to_compcode (enum tree_code code)
2212 return COMPCODE_ORD;
2213 case UNORDERED_EXPR:
2214 return COMPCODE_UNORD;
2216 return COMPCODE_UNLT;
2218 return COMPCODE_UNEQ;
2220 return COMPCODE_UNLE;
2222 return COMPCODE_UNGT;
2224 return COMPCODE_LTGT;
2226 return COMPCODE_UNGE;
2232 /* Convert a compcode bit-based encoding of a comparison operator back
2233 to GCC's enum tree_code representation. This function is the
2234 inverse of comparison_to_compcode. */
2236 static enum tree_code
2237 compcode_to_comparison (enum comparison_code code)
2254 return ORDERED_EXPR;
2255 case COMPCODE_UNORD:
2256 return UNORDERED_EXPR;
2274 /* Return a tree for the comparison which is the combination of
2275 doing the AND or OR (depending on CODE) of the two operations LCODE
2276 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2277 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2278 if this makes the transformation invalid. */
2281 combine_comparisons (location_t loc,
2282 enum tree_code code, enum tree_code lcode,
2283 enum tree_code rcode, tree truth_type,
2284 tree ll_arg, tree lr_arg)
2286 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2287 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2288 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2293 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2294 compcode = lcompcode & rcompcode;
2297 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2298 compcode = lcompcode | rcompcode;
2307 /* Eliminate unordered comparisons, as well as LTGT and ORD
2308 which are not used unless the mode has NaNs. */
2309 compcode &= ~COMPCODE_UNORD;
2310 if (compcode == COMPCODE_LTGT)
2311 compcode = COMPCODE_NE;
2312 else if (compcode == COMPCODE_ORD)
2313 compcode = COMPCODE_TRUE;
2315 else if (flag_trapping_math)
2317 /* Check that the original operation and the optimized ones will trap
2318 under the same condition. */
2319 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2320 && (lcompcode != COMPCODE_EQ)
2321 && (lcompcode != COMPCODE_ORD);
2322 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2323 && (rcompcode != COMPCODE_EQ)
2324 && (rcompcode != COMPCODE_ORD);
2325 bool trap = (compcode & COMPCODE_UNORD) == 0
2326 && (compcode != COMPCODE_EQ)
2327 && (compcode != COMPCODE_ORD);
2329 /* In a short-circuited boolean expression the LHS might be
2330 such that the RHS, if evaluated, will never trap. For
2331 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2332 if neither x nor y is NaN. (This is a mixed blessing: for
2333 example, the expression above will never trap, hence
2334 optimizing it to x < y would be invalid). */
2335 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2336 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2339 /* If the comparison was short-circuited, and only the RHS
2340 trapped, we may now generate a spurious trap. */
2342 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2345 /* If we changed the conditions that cause a trap, we lose. */
2346 if ((ltrap || rtrap) != trap)
2350 if (compcode == COMPCODE_TRUE)
2351 return constant_boolean_node (true, truth_type);
2352 else if (compcode == COMPCODE_FALSE)
2353 return constant_boolean_node (false, truth_type);
2356 enum tree_code tcode;
2358 tcode = compcode_to_comparison ((enum comparison_code) compcode);
2359 return fold_build2_loc (loc, tcode, truth_type, ll_arg, lr_arg);
2363 /* Return nonzero if two operands (typically of the same tree node)
2364 are necessarily equal. If either argument has side-effects this
2365 function returns zero. FLAGS modifies behavior as follows:
2367 If OEP_ONLY_CONST is set, only return nonzero for constants.
2368 This function tests whether the operands are indistinguishable;
2369 it does not test whether they are equal using C's == operation.
2370 The distinction is important for IEEE floating point, because
2371 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2372 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2374 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2375 even though it may hold multiple values during a function.
2376 This is because a GCC tree node guarantees that nothing else is
2377 executed between the evaluation of its "operands" (which may often
2378 be evaluated in arbitrary order). Hence if the operands themselves
2379 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
2380 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
2381 unset means assuming isochronic (or instantaneous) tree equivalence.
2382 Unless comparing arbitrary expression trees, such as from different
2383 statements, this flag can usually be left unset.
2385 If OEP_PURE_SAME is set, then pure functions with identical arguments
2386 are considered the same. It is used when the caller has other ways
2387 to ensure that global memory is unchanged in between. */
2390 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
2392 /* If either is ERROR_MARK, they aren't equal. */
2393 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK
2394 || TREE_TYPE (arg0) == error_mark_node
2395 || TREE_TYPE (arg1) == error_mark_node)
2398 /* Similar, if either does not have a type (like a released SSA name),
2399 they aren't equal. */
2400 if (!TREE_TYPE (arg0) || !TREE_TYPE (arg1))
2403 /* Check equality of integer constants before bailing out due to
2404 precision differences. */
2405 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2406 return tree_int_cst_equal (arg0, arg1);
2408 /* If both types don't have the same signedness, then we can't consider
2409 them equal. We must check this before the STRIP_NOPS calls
2410 because they may change the signedness of the arguments. As pointers
2411 strictly don't have a signedness, require either two pointers or
2412 two non-pointers as well. */
2413 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
2414 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
2417 /* We cannot consider pointers to different address space equal. */
2418 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && POINTER_TYPE_P (TREE_TYPE (arg1))
2419 && (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg0)))
2420 != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg1)))))
2423 /* If both types don't have the same precision, then it is not safe
2425 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
2431 /* In case both args are comparisons but with different comparison
2432 code, try to swap the comparison operands of one arg to produce
2433 a match and compare that variant. */
2434 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2435 && COMPARISON_CLASS_P (arg0)
2436 && COMPARISON_CLASS_P (arg1))
2438 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
2440 if (TREE_CODE (arg0) == swap_code)
2441 return operand_equal_p (TREE_OPERAND (arg0, 0),
2442 TREE_OPERAND (arg1, 1), flags)
2443 && operand_equal_p (TREE_OPERAND (arg0, 1),
2444 TREE_OPERAND (arg1, 0), flags);
2447 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2448 /* This is needed for conversions and for COMPONENT_REF.
2449 Might as well play it safe and always test this. */
2450 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
2451 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
2452 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
2455 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
2456 We don't care about side effects in that case because the SAVE_EXPR
2457 takes care of that for us. In all other cases, two expressions are
2458 equal if they have no side effects. If we have two identical
2459 expressions with side effects that should be treated the same due
2460 to the only side effects being identical SAVE_EXPR's, that will
2461 be detected in the recursive calls below.
2462 If we are taking an invariant address of two identical objects
2463 they are necessarily equal as well. */
2464 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
2465 && (TREE_CODE (arg0) == SAVE_EXPR
2466 || (flags & OEP_CONSTANT_ADDRESS_OF)
2467 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
2470 /* Next handle constant cases, those for which we can return 1 even
2471 if ONLY_CONST is set. */
2472 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
2473 switch (TREE_CODE (arg0))
2476 return tree_int_cst_equal (arg0, arg1);
2479 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
2480 TREE_FIXED_CST (arg1));
2483 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
2484 TREE_REAL_CST (arg1)))
2488 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
2490 /* If we do not distinguish between signed and unsigned zero,
2491 consider them equal. */
2492 if (real_zerop (arg0) && real_zerop (arg1))
2501 v1 = TREE_VECTOR_CST_ELTS (arg0);
2502 v2 = TREE_VECTOR_CST_ELTS (arg1);
2505 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
2508 v1 = TREE_CHAIN (v1);
2509 v2 = TREE_CHAIN (v2);
2516 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
2518 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
2522 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
2523 && ! memcmp (TREE_STRING_POINTER (arg0),
2524 TREE_STRING_POINTER (arg1),
2525 TREE_STRING_LENGTH (arg0)));
2528 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
2529 TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1)
2530 ? OEP_CONSTANT_ADDRESS_OF : 0);
2535 if (flags & OEP_ONLY_CONST)
2538 /* Define macros to test an operand from arg0 and arg1 for equality and a
2539 variant that allows null and views null as being different from any
2540 non-null value. In the latter case, if either is null, the both
2541 must be; otherwise, do the normal comparison. */
2542 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
2543 TREE_OPERAND (arg1, N), flags)
2545 #define OP_SAME_WITH_NULL(N) \
2546 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
2547 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
2549 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
2552 /* Two conversions are equal only if signedness and modes match. */
2553 switch (TREE_CODE (arg0))
2556 case FIX_TRUNC_EXPR:
2557 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
2558 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
2568 case tcc_comparison:
2570 if (OP_SAME (0) && OP_SAME (1))
2573 /* For commutative ops, allow the other order. */
2574 return (commutative_tree_code (TREE_CODE (arg0))
2575 && operand_equal_p (TREE_OPERAND (arg0, 0),
2576 TREE_OPERAND (arg1, 1), flags)
2577 && operand_equal_p (TREE_OPERAND (arg0, 1),
2578 TREE_OPERAND (arg1, 0), flags));
2581 /* If either of the pointer (or reference) expressions we are
2582 dereferencing contain a side effect, these cannot be equal. */
2583 if (TREE_SIDE_EFFECTS (arg0)
2584 || TREE_SIDE_EFFECTS (arg1))
2587 switch (TREE_CODE (arg0))
2595 /* Require equal access sizes, and similar pointer types.
2596 We can have incomplete types for array references of
2597 variable-sized arrays from the Fortran frontent
2599 return ((TYPE_SIZE (TREE_TYPE (arg0)) == TYPE_SIZE (TREE_TYPE (arg1))
2600 || (TYPE_SIZE (TREE_TYPE (arg0))
2601 && TYPE_SIZE (TREE_TYPE (arg1))
2602 && operand_equal_p (TYPE_SIZE (TREE_TYPE (arg0)),
2603 TYPE_SIZE (TREE_TYPE (arg1)), flags)))
2604 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg0, 1)))
2605 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg1, 1))))
2606 && OP_SAME (0) && OP_SAME (1));
2609 case ARRAY_RANGE_REF:
2610 /* Operands 2 and 3 may be null.
2611 Compare the array index by value if it is constant first as we
2612 may have different types but same value here. */
2614 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
2615 TREE_OPERAND (arg1, 1))
2617 && OP_SAME_WITH_NULL (2)
2618 && OP_SAME_WITH_NULL (3));
2621 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
2622 may be NULL when we're called to compare MEM_EXPRs. */
2623 return OP_SAME_WITH_NULL (0)
2625 && OP_SAME_WITH_NULL (2);
2628 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2634 case tcc_expression:
2635 switch (TREE_CODE (arg0))
2638 case TRUTH_NOT_EXPR:
2641 case TRUTH_ANDIF_EXPR:
2642 case TRUTH_ORIF_EXPR:
2643 return OP_SAME (0) && OP_SAME (1);
2646 case WIDEN_MULT_PLUS_EXPR:
2647 case WIDEN_MULT_MINUS_EXPR:
2650 /* The multiplcation operands are commutative. */
2653 case TRUTH_AND_EXPR:
2655 case TRUTH_XOR_EXPR:
2656 if (OP_SAME (0) && OP_SAME (1))
2659 /* Otherwise take into account this is a commutative operation. */
2660 return (operand_equal_p (TREE_OPERAND (arg0, 0),
2661 TREE_OPERAND (arg1, 1), flags)
2662 && operand_equal_p (TREE_OPERAND (arg0, 1),
2663 TREE_OPERAND (arg1, 0), flags));
2668 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2675 switch (TREE_CODE (arg0))
2678 /* If the CALL_EXPRs call different functions, then they
2679 clearly can not be equal. */
2680 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
2685 unsigned int cef = call_expr_flags (arg0);
2686 if (flags & OEP_PURE_SAME)
2687 cef &= ECF_CONST | ECF_PURE;
2694 /* Now see if all the arguments are the same. */
2696 const_call_expr_arg_iterator iter0, iter1;
2698 for (a0 = first_const_call_expr_arg (arg0, &iter0),
2699 a1 = first_const_call_expr_arg (arg1, &iter1);
2701 a0 = next_const_call_expr_arg (&iter0),
2702 a1 = next_const_call_expr_arg (&iter1))
2703 if (! operand_equal_p (a0, a1, flags))
2706 /* If we get here and both argument lists are exhausted
2707 then the CALL_EXPRs are equal. */
2708 return ! (a0 || a1);
2714 case tcc_declaration:
2715 /* Consider __builtin_sqrt equal to sqrt. */
2716 return (TREE_CODE (arg0) == FUNCTION_DECL
2717 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
2718 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
2719 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
2726 #undef OP_SAME_WITH_NULL
2729 /* Similar to operand_equal_p, but see if ARG0 might have been made by
2730 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
2732 When in doubt, return 0. */
2735 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
2737 int unsignedp1, unsignedpo;
2738 tree primarg0, primarg1, primother;
2739 unsigned int correct_width;
2741 if (operand_equal_p (arg0, arg1, 0))
2744 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
2745 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
2748 /* Discard any conversions that don't change the modes of ARG0 and ARG1
2749 and see if the inner values are the same. This removes any
2750 signedness comparison, which doesn't matter here. */
2751 primarg0 = arg0, primarg1 = arg1;
2752 STRIP_NOPS (primarg0);
2753 STRIP_NOPS (primarg1);
2754 if (operand_equal_p (primarg0, primarg1, 0))
2757 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
2758 actual comparison operand, ARG0.
2760 First throw away any conversions to wider types
2761 already present in the operands. */
2763 primarg1 = get_narrower (arg1, &unsignedp1);
2764 primother = get_narrower (other, &unsignedpo);
2766 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
2767 if (unsignedp1 == unsignedpo
2768 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
2769 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
2771 tree type = TREE_TYPE (arg0);
2773 /* Make sure shorter operand is extended the right way
2774 to match the longer operand. */
2775 primarg1 = fold_convert (signed_or_unsigned_type_for
2776 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
2778 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
2785 /* See if ARG is an expression that is either a comparison or is performing
2786 arithmetic on comparisons. The comparisons must only be comparing
2787 two different values, which will be stored in *CVAL1 and *CVAL2; if
2788 they are nonzero it means that some operands have already been found.
2789 No variables may be used anywhere else in the expression except in the
2790 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
2791 the expression and save_expr needs to be called with CVAL1 and CVAL2.
2793 If this is true, return 1. Otherwise, return zero. */
2796 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
2798 enum tree_code code = TREE_CODE (arg);
2799 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2801 /* We can handle some of the tcc_expression cases here. */
2802 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2804 else if (tclass == tcc_expression
2805 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
2806 || code == COMPOUND_EXPR))
2807 tclass = tcc_binary;
2809 else if (tclass == tcc_expression && code == SAVE_EXPR
2810 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
2812 /* If we've already found a CVAL1 or CVAL2, this expression is
2813 two complex to handle. */
2814 if (*cval1 || *cval2)
2824 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
2827 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
2828 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2829 cval1, cval2, save_p));
2834 case tcc_expression:
2835 if (code == COND_EXPR)
2836 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
2837 cval1, cval2, save_p)
2838 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2839 cval1, cval2, save_p)
2840 && twoval_comparison_p (TREE_OPERAND (arg, 2),
2841 cval1, cval2, save_p));
2844 case tcc_comparison:
2845 /* First see if we can handle the first operand, then the second. For
2846 the second operand, we know *CVAL1 can't be zero. It must be that
2847 one side of the comparison is each of the values; test for the
2848 case where this isn't true by failing if the two operands
2851 if (operand_equal_p (TREE_OPERAND (arg, 0),
2852 TREE_OPERAND (arg, 1), 0))
2856 *cval1 = TREE_OPERAND (arg, 0);
2857 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
2859 else if (*cval2 == 0)
2860 *cval2 = TREE_OPERAND (arg, 0);
2861 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
2866 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
2868 else if (*cval2 == 0)
2869 *cval2 = TREE_OPERAND (arg, 1);
2870 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
2882 /* ARG is a tree that is known to contain just arithmetic operations and
2883 comparisons. Evaluate the operations in the tree substituting NEW0 for
2884 any occurrence of OLD0 as an operand of a comparison and likewise for
2888 eval_subst (location_t loc, tree arg, tree old0, tree new0,
2889 tree old1, tree new1)
2891 tree type = TREE_TYPE (arg);
2892 enum tree_code code = TREE_CODE (arg);
2893 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2895 /* We can handle some of the tcc_expression cases here. */
2896 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2898 else if (tclass == tcc_expression
2899 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2900 tclass = tcc_binary;
2905 return fold_build1_loc (loc, code, type,
2906 eval_subst (loc, TREE_OPERAND (arg, 0),
2907 old0, new0, old1, new1));
2910 return fold_build2_loc (loc, code, type,
2911 eval_subst (loc, TREE_OPERAND (arg, 0),
2912 old0, new0, old1, new1),
2913 eval_subst (loc, TREE_OPERAND (arg, 1),
2914 old0, new0, old1, new1));
2916 case tcc_expression:
2920 return eval_subst (loc, TREE_OPERAND (arg, 0), old0, new0,
2924 return eval_subst (loc, TREE_OPERAND (arg, 1), old0, new0,
2928 return fold_build3_loc (loc, code, type,
2929 eval_subst (loc, TREE_OPERAND (arg, 0),
2930 old0, new0, old1, new1),
2931 eval_subst (loc, TREE_OPERAND (arg, 1),
2932 old0, new0, old1, new1),
2933 eval_subst (loc, TREE_OPERAND (arg, 2),
2934 old0, new0, old1, new1));
2938 /* Fall through - ??? */
2940 case tcc_comparison:
2942 tree arg0 = TREE_OPERAND (arg, 0);
2943 tree arg1 = TREE_OPERAND (arg, 1);
2945 /* We need to check both for exact equality and tree equality. The
2946 former will be true if the operand has a side-effect. In that
2947 case, we know the operand occurred exactly once. */
2949 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
2951 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
2954 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
2956 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
2959 return fold_build2_loc (loc, code, type, arg0, arg1);
2967 /* Return a tree for the case when the result of an expression is RESULT
2968 converted to TYPE and OMITTED was previously an operand of the expression
2969 but is now not needed (e.g., we folded OMITTED * 0).
2971 If OMITTED has side effects, we must evaluate it. Otherwise, just do
2972 the conversion of RESULT to TYPE. */
2975 omit_one_operand_loc (location_t loc, tree type, tree result, tree omitted)
2977 tree t = fold_convert_loc (loc, type, result);
2979 /* If the resulting operand is an empty statement, just return the omitted
2980 statement casted to void. */
2981 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
2982 return build1_loc (loc, NOP_EXPR, void_type_node,
2983 fold_ignored_result (omitted));
2985 if (TREE_SIDE_EFFECTS (omitted))
2986 return build2_loc (loc, COMPOUND_EXPR, type,
2987 fold_ignored_result (omitted), t);
2989 return non_lvalue_loc (loc, t);
2992 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
2995 pedantic_omit_one_operand_loc (location_t loc, tree type, tree result,
2998 tree t = fold_convert_loc (loc, type, result);
3000 /* If the resulting operand is an empty statement, just return the omitted
3001 statement casted to void. */
3002 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3003 return build1_loc (loc, NOP_EXPR, void_type_node,
3004 fold_ignored_result (omitted));
3006 if (TREE_SIDE_EFFECTS (omitted))
3007 return build2_loc (loc, COMPOUND_EXPR, type,
3008 fold_ignored_result (omitted), t);
3010 return pedantic_non_lvalue_loc (loc, t);
3013 /* Return a tree for the case when the result of an expression is RESULT
3014 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3015 of the expression but are now not needed.
3017 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3018 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3019 evaluated before OMITTED2. Otherwise, if neither has side effects,
3020 just do the conversion of RESULT to TYPE. */
3023 omit_two_operands_loc (location_t loc, tree type, tree result,
3024 tree omitted1, tree omitted2)
3026 tree t = fold_convert_loc (loc, type, result);
3028 if (TREE_SIDE_EFFECTS (omitted2))
3029 t = build2_loc (loc, COMPOUND_EXPR, type, omitted2, t);
3030 if (TREE_SIDE_EFFECTS (omitted1))
3031 t = build2_loc (loc, COMPOUND_EXPR, type, omitted1, t);
3033 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue_loc (loc, t) : t;
3037 /* Return a simplified tree node for the truth-negation of ARG. This
3038 never alters ARG itself. We assume that ARG is an operation that
3039 returns a truth value (0 or 1).
3041 FIXME: one would think we would fold the result, but it causes
3042 problems with the dominator optimizer. */
3045 fold_truth_not_expr (location_t loc, tree arg)
3047 tree type = TREE_TYPE (arg);
3048 enum tree_code code = TREE_CODE (arg);
3049 location_t loc1, loc2;
3051 /* If this is a comparison, we can simply invert it, except for
3052 floating-point non-equality comparisons, in which case we just
3053 enclose a TRUTH_NOT_EXPR around what we have. */
3055 if (TREE_CODE_CLASS (code) == tcc_comparison)
3057 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3058 if (FLOAT_TYPE_P (op_type)
3059 && flag_trapping_math
3060 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3061 && code != NE_EXPR && code != EQ_EXPR)
3064 code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (op_type)));
3065 if (code == ERROR_MARK)
3068 return build2_loc (loc, code, type, TREE_OPERAND (arg, 0),
3069 TREE_OPERAND (arg, 1));
3075 return constant_boolean_node (integer_zerop (arg), type);
3077 case TRUTH_AND_EXPR:
3078 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3079 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3080 return build2_loc (loc, TRUTH_OR_EXPR, type,
3081 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3082 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3085 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3086 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3087 return build2_loc (loc, TRUTH_AND_EXPR, type,
3088 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3089 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3091 case TRUTH_XOR_EXPR:
3092 /* Here we can invert either operand. We invert the first operand
3093 unless the second operand is a TRUTH_NOT_EXPR in which case our
3094 result is the XOR of the first operand with the inside of the
3095 negation of the second operand. */
3097 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3098 return build2_loc (loc, TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3099 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3101 return build2_loc (loc, TRUTH_XOR_EXPR, type,
3102 invert_truthvalue_loc (loc, TREE_OPERAND (arg, 0)),
3103 TREE_OPERAND (arg, 1));
3105 case TRUTH_ANDIF_EXPR:
3106 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3107 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3108 return build2_loc (loc, TRUTH_ORIF_EXPR, type,
3109 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3110 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3112 case TRUTH_ORIF_EXPR:
3113 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3114 loc2 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3115 return build2_loc (loc, TRUTH_ANDIF_EXPR, type,
3116 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3117 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3119 case TRUTH_NOT_EXPR:
3120 return TREE_OPERAND (arg, 0);
3124 tree arg1 = TREE_OPERAND (arg, 1);
3125 tree arg2 = TREE_OPERAND (arg, 2);
3127 loc1 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3128 loc2 = expr_location_or (TREE_OPERAND (arg, 2), loc);
3130 /* A COND_EXPR may have a throw as one operand, which
3131 then has void type. Just leave void operands
3133 return build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg, 0),
3134 VOID_TYPE_P (TREE_TYPE (arg1))
3135 ? arg1 : invert_truthvalue_loc (loc1, arg1),
3136 VOID_TYPE_P (TREE_TYPE (arg2))
3137 ? arg2 : invert_truthvalue_loc (loc2, arg2));
3141 loc1 = expr_location_or (TREE_OPERAND (arg, 1), loc);
3142 return build2_loc (loc, COMPOUND_EXPR, type,
3143 TREE_OPERAND (arg, 0),
3144 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 1)));
3146 case NON_LVALUE_EXPR:
3147 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3148 return invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0));
3151 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3152 return build1_loc (loc, TRUTH_NOT_EXPR, type, arg);
3154 /* ... fall through ... */
3157 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3158 return build1_loc (loc, TREE_CODE (arg), type,
3159 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3162 if (!integer_onep (TREE_OPERAND (arg, 1)))
3164 return build2_loc (loc, EQ_EXPR, type, arg, build_int_cst (type, 0));
3167 return build1_loc (loc, TRUTH_NOT_EXPR, type, arg);
3169 case CLEANUP_POINT_EXPR:
3170 loc1 = expr_location_or (TREE_OPERAND (arg, 0), loc);
3171 return build1_loc (loc, CLEANUP_POINT_EXPR, type,
3172 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3179 /* Return a simplified tree node for the truth-negation of ARG. This
3180 never alters ARG itself. We assume that ARG is an operation that
3181 returns a truth value (0 or 1).
3183 FIXME: one would think we would fold the result, but it causes
3184 problems with the dominator optimizer. */
3187 invert_truthvalue_loc (location_t loc, tree arg)
3191 if (TREE_CODE (arg) == ERROR_MARK)
3194 tem = fold_truth_not_expr (loc, arg);
3196 tem = build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3201 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3202 operands are another bit-wise operation with a common input. If so,
3203 distribute the bit operations to save an operation and possibly two if
3204 constants are involved. For example, convert
3205 (A | B) & (A | C) into A | (B & C)
3206 Further simplification will occur if B and C are constants.
3208 If this optimization cannot be done, 0 will be returned. */
3211 distribute_bit_expr (location_t loc, enum tree_code code, tree type,
3212 tree arg0, tree arg1)
3217 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3218 || TREE_CODE (arg0) == code
3219 || (TREE_CODE (arg0) != BIT_AND_EXPR
3220 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3223 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3225 common = TREE_OPERAND (arg0, 0);
3226 left = TREE_OPERAND (arg0, 1);
3227 right = TREE_OPERAND (arg1, 1);
3229 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3231 common = TREE_OPERAND (arg0, 0);
3232 left = TREE_OPERAND (arg0, 1);
3233 right = TREE_OPERAND (arg1, 0);
3235 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3237 common = TREE_OPERAND (arg0, 1);
3238 left = TREE_OPERAND (arg0, 0);
3239 right = TREE_OPERAND (arg1, 1);
3241 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3243 common = TREE_OPERAND (arg0, 1);
3244 left = TREE_OPERAND (arg0, 0);
3245 right = TREE_OPERAND (arg1, 0);
3250 common = fold_convert_loc (loc, type, common);
3251 left = fold_convert_loc (loc, type, left);
3252 right = fold_convert_loc (loc, type, right);
3253 return fold_build2_loc (loc, TREE_CODE (arg0), type, common,
3254 fold_build2_loc (loc, code, type, left, right));
3257 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3258 with code CODE. This optimization is unsafe. */
3260 distribute_real_division (location_t loc, enum tree_code code, tree type,
3261 tree arg0, tree arg1)
3263 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3264 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3266 /* (A / C) +- (B / C) -> (A +- B) / C. */
3268 && operand_equal_p (TREE_OPERAND (arg0, 1),
3269 TREE_OPERAND (arg1, 1), 0))
3270 return fold_build2_loc (loc, mul0 ? MULT_EXPR : RDIV_EXPR, type,
3271 fold_build2_loc (loc, code, type,
3272 TREE_OPERAND (arg0, 0),
3273 TREE_OPERAND (arg1, 0)),
3274 TREE_OPERAND (arg0, 1));
3276 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3277 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3278 TREE_OPERAND (arg1, 0), 0)
3279 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3280 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3282 REAL_VALUE_TYPE r0, r1;
3283 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3284 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3286 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3288 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3289 real_arithmetic (&r0, code, &r0, &r1);
3290 return fold_build2_loc (loc, MULT_EXPR, type,
3291 TREE_OPERAND (arg0, 0),
3292 build_real (type, r0));
3298 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3299 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3302 make_bit_field_ref (location_t loc, tree inner, tree type,
3303 HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos, int unsignedp)
3305 tree result, bftype;
3309 tree size = TYPE_SIZE (TREE_TYPE (inner));
3310 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
3311 || POINTER_TYPE_P (TREE_TYPE (inner)))
3312 && host_integerp (size, 0)
3313 && tree_low_cst (size, 0) == bitsize)
3314 return fold_convert_loc (loc, type, inner);
3318 if (TYPE_PRECISION (bftype) != bitsize
3319 || TYPE_UNSIGNED (bftype) == !unsignedp)
3320 bftype = build_nonstandard_integer_type (bitsize, 0);
3322 result = build3_loc (loc, BIT_FIELD_REF, bftype, inner,
3323 size_int (bitsize), bitsize_int (bitpos));
3326 result = fold_convert_loc (loc, type, result);
3331 /* Optimize a bit-field compare.
3333 There are two cases: First is a compare against a constant and the
3334 second is a comparison of two items where the fields are at the same
3335 bit position relative to the start of a chunk (byte, halfword, word)
3336 large enough to contain it. In these cases we can avoid the shift
3337 implicit in bitfield extractions.
3339 For constants, we emit a compare of the shifted constant with the
3340 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3341 compared. For two fields at the same position, we do the ANDs with the
3342 similar mask and compare the result of the ANDs.
3344 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3345 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3346 are the left and right operands of the comparison, respectively.
3348 If the optimization described above can be done, we return the resulting
3349 tree. Otherwise we return zero. */
3352 optimize_bit_field_compare (location_t loc, enum tree_code code,
3353 tree compare_type, tree lhs, tree rhs)
3355 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
3356 tree type = TREE_TYPE (lhs);
3357 tree signed_type, unsigned_type;
3358 int const_p = TREE_CODE (rhs) == INTEGER_CST;
3359 enum machine_mode lmode, rmode, nmode;
3360 int lunsignedp, runsignedp;
3361 int lvolatilep = 0, rvolatilep = 0;
3362 tree linner, rinner = NULL_TREE;
3366 /* Get all the information about the extractions being done. If the bit size
3367 if the same as the size of the underlying object, we aren't doing an
3368 extraction at all and so can do nothing. We also don't want to
3369 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3370 then will no longer be able to replace it. */
3371 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
3372 &lunsignedp, &lvolatilep, false);
3373 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
3374 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
3379 /* If this is not a constant, we can only do something if bit positions,
3380 sizes, and signedness are the same. */
3381 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
3382 &runsignedp, &rvolatilep, false);
3384 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
3385 || lunsignedp != runsignedp || offset != 0
3386 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
3390 /* See if we can find a mode to refer to this field. We should be able to,
3391 but fail if we can't. */
3393 && GET_MODE_BITSIZE (lmode) > 0
3394 && flag_strict_volatile_bitfields > 0)
3397 nmode = get_best_mode (lbitsize, lbitpos,
3398 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
3399 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
3400 TYPE_ALIGN (TREE_TYPE (rinner))),
3401 word_mode, lvolatilep || rvolatilep);
3402 if (nmode == VOIDmode)
3405 /* Set signed and unsigned types of the precision of this mode for the
3407 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
3408 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
3410 /* Compute the bit position and size for the new reference and our offset
3411 within it. If the new reference is the same size as the original, we
3412 won't optimize anything, so return zero. */
3413 nbitsize = GET_MODE_BITSIZE (nmode);
3414 nbitpos = lbitpos & ~ (nbitsize - 1);
3416 if (nbitsize == lbitsize)
3419 if (BYTES_BIG_ENDIAN)
3420 lbitpos = nbitsize - lbitsize - lbitpos;
3422 /* Make the mask to be used against the extracted field. */
3423 mask = build_int_cst_type (unsigned_type, -1);
3424 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize));
3425 mask = const_binop (RSHIFT_EXPR, mask,
3426 size_int (nbitsize - lbitsize - lbitpos));
3429 /* If not comparing with constant, just rework the comparison
3431 return fold_build2_loc (loc, code, compare_type,
3432 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3433 make_bit_field_ref (loc, linner,
3438 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3439 make_bit_field_ref (loc, rinner,
3445 /* Otherwise, we are handling the constant case. See if the constant is too
3446 big for the field. Warn and return a tree of for 0 (false) if so. We do
3447 this not only for its own sake, but to avoid having to test for this
3448 error case below. If we didn't, we might generate wrong code.
3450 For unsigned fields, the constant shifted right by the field length should
3451 be all zero. For signed fields, the high-order bits should agree with
3456 if (! integer_zerop (const_binop (RSHIFT_EXPR,
3457 fold_convert_loc (loc,
3458 unsigned_type, rhs),
3459 size_int (lbitsize))))
3461 warning (0, "comparison is always %d due to width of bit-field",
3463 return constant_boolean_node (code == NE_EXPR, compare_type);
3468 tree tem = const_binop (RSHIFT_EXPR,
3469 fold_convert_loc (loc, signed_type, rhs),
3470 size_int (lbitsize - 1));
3471 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
3473 warning (0, "comparison is always %d due to width of bit-field",
3475 return constant_boolean_node (code == NE_EXPR, compare_type);
3479 /* Single-bit compares should always be against zero. */
3480 if (lbitsize == 1 && ! integer_zerop (rhs))
3482 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
3483 rhs = build_int_cst (type, 0);
3486 /* Make a new bitfield reference, shift the constant over the
3487 appropriate number of bits and mask it with the computed mask
3488 (in case this was a signed field). If we changed it, make a new one. */
3489 lhs = make_bit_field_ref (loc, linner, unsigned_type, nbitsize, nbitpos, 1);
3492 TREE_SIDE_EFFECTS (lhs) = 1;
3493 TREE_THIS_VOLATILE (lhs) = 1;
3496 rhs = const_binop (BIT_AND_EXPR,
3497 const_binop (LSHIFT_EXPR,
3498 fold_convert_loc (loc, unsigned_type, rhs),
3499 size_int (lbitpos)),
3502 lhs = build2_loc (loc, code, compare_type,
3503 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask), rhs);
3507 /* Subroutine for fold_truthop: decode a field reference.
3509 If EXP is a comparison reference, we return the innermost reference.
3511 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
3512 set to the starting bit number.
3514 If the innermost field can be completely contained in a mode-sized
3515 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
3517 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
3518 otherwise it is not changed.
3520 *PUNSIGNEDP is set to the signedness of the field.
3522 *PMASK is set to the mask used. This is either contained in a
3523 BIT_AND_EXPR or derived from the width of the field.
3525 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
3527 Return 0 if this is not a component reference or is one that we can't
3528 do anything with. */
3531 decode_field_reference (location_t loc, tree exp, HOST_WIDE_INT *pbitsize,
3532 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
3533 int *punsignedp, int *pvolatilep,
3534 tree *pmask, tree *pand_mask)
3536 tree outer_type = 0;
3538 tree mask, inner, offset;
3540 unsigned int precision;
3542 /* All the optimizations using this function assume integer fields.
3543 There are problems with FP fields since the type_for_size call
3544 below can fail for, e.g., XFmode. */
3545 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
3548 /* We are interested in the bare arrangement of bits, so strip everything
3549 that doesn't affect the machine mode. However, record the type of the
3550 outermost expression if it may matter below. */
3551 if (CONVERT_EXPR_P (exp)
3552 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3553 outer_type = TREE_TYPE (exp);
3556 if (TREE_CODE (exp) == BIT_AND_EXPR)
3558 and_mask = TREE_OPERAND (exp, 1);
3559 exp = TREE_OPERAND (exp, 0);
3560 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
3561 if (TREE_CODE (and_mask) != INTEGER_CST)
3565 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
3566 punsignedp, pvolatilep, false);
3567 if ((inner == exp && and_mask == 0)
3568 || *pbitsize < 0 || offset != 0
3569 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
3572 /* If the number of bits in the reference is the same as the bitsize of
3573 the outer type, then the outer type gives the signedness. Otherwise
3574 (in case of a small bitfield) the signedness is unchanged. */
3575 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
3576 *punsignedp = TYPE_UNSIGNED (outer_type);
3578 /* Compute the mask to access the bitfield. */
3579 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
3580 precision = TYPE_PRECISION (unsigned_type);
3582 mask = build_int_cst_type (unsigned_type, -1);
3584 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3585 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3587 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
3589 mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3590 fold_convert_loc (loc, unsigned_type, and_mask), mask);
3593 *pand_mask = and_mask;
3597 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
3601 all_ones_mask_p (const_tree mask, int size)
3603 tree type = TREE_TYPE (mask);
3604 unsigned int precision = TYPE_PRECISION (type);
3607 tmask = build_int_cst_type (signed_type_for (type), -1);
3610 tree_int_cst_equal (mask,
3611 const_binop (RSHIFT_EXPR,
3612 const_binop (LSHIFT_EXPR, tmask,
3613 size_int (precision - size)),
3614 size_int (precision - size)));
3617 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
3618 represents the sign bit of EXP's type. If EXP represents a sign
3619 or zero extension, also test VAL against the unextended type.
3620 The return value is the (sub)expression whose sign bit is VAL,
3621 or NULL_TREE otherwise. */
3624 sign_bit_p (tree exp, const_tree val)
3626 unsigned HOST_WIDE_INT mask_lo, lo;
3627 HOST_WIDE_INT mask_hi, hi;
3631 /* Tree EXP must have an integral type. */
3632 t = TREE_TYPE (exp);
3633 if (! INTEGRAL_TYPE_P (t))
3636 /* Tree VAL must be an integer constant. */
3637 if (TREE_CODE (val) != INTEGER_CST
3638 || TREE_OVERFLOW (val))
3641 width = TYPE_PRECISION (t);
3642 if (width > HOST_BITS_PER_WIDE_INT)
3644 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
3647 mask_hi = ((unsigned HOST_WIDE_INT) -1
3648 >> (2 * HOST_BITS_PER_WIDE_INT - width));
3654 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
3657 mask_lo = ((unsigned HOST_WIDE_INT) -1
3658 >> (HOST_BITS_PER_WIDE_INT - width));
3661 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
3662 treat VAL as if it were unsigned. */
3663 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
3664 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
3667 /* Handle extension from a narrower type. */
3668 if (TREE_CODE (exp) == NOP_EXPR
3669 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
3670 return sign_bit_p (TREE_OPERAND (exp, 0), val);
3675 /* Subroutine for fold_truthop: determine if an operand is simple enough
3676 to be evaluated unconditionally. */
3679 simple_operand_p (const_tree exp)
3681 /* Strip any conversions that don't change the machine mode. */
3684 return (CONSTANT_CLASS_P (exp)
3685 || TREE_CODE (exp) == SSA_NAME
3687 && ! TREE_ADDRESSABLE (exp)
3688 && ! TREE_THIS_VOLATILE (exp)
3689 && ! DECL_NONLOCAL (exp)
3690 /* Don't regard global variables as simple. They may be
3691 allocated in ways unknown to the compiler (shared memory,
3692 #pragma weak, etc). */
3693 && ! TREE_PUBLIC (exp)
3694 && ! DECL_EXTERNAL (exp)
3695 /* Loading a static variable is unduly expensive, but global
3696 registers aren't expensive. */
3697 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
3700 /* The following functions are subroutines to fold_range_test and allow it to
3701 try to change a logical combination of comparisons into a range test.
3704 X == 2 || X == 3 || X == 4 || X == 5
3708 (unsigned) (X - 2) <= 3
3710 We describe each set of comparisons as being either inside or outside
3711 a range, using a variable named like IN_P, and then describe the
3712 range with a lower and upper bound. If one of the bounds is omitted,
3713 it represents either the highest or lowest value of the type.
3715 In the comments below, we represent a range by two numbers in brackets
3716 preceded by a "+" to designate being inside that range, or a "-" to
3717 designate being outside that range, so the condition can be inverted by
3718 flipping the prefix. An omitted bound is represented by a "-". For
3719 example, "- [-, 10]" means being outside the range starting at the lowest
3720 possible value and ending at 10, in other words, being greater than 10.
3721 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
3724 We set up things so that the missing bounds are handled in a consistent
3725 manner so neither a missing bound nor "true" and "false" need to be
3726 handled using a special case. */
3728 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
3729 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
3730 and UPPER1_P are nonzero if the respective argument is an upper bound
3731 and zero for a lower. TYPE, if nonzero, is the type of the result; it
3732 must be specified for a comparison. ARG1 will be converted to ARG0's
3733 type if both are specified. */
3736 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
3737 tree arg1, int upper1_p)
3743 /* If neither arg represents infinity, do the normal operation.
3744 Else, if not a comparison, return infinity. Else handle the special
3745 comparison rules. Note that most of the cases below won't occur, but
3746 are handled for consistency. */
3748 if (arg0 != 0 && arg1 != 0)
3750 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
3751 arg0, fold_convert (TREE_TYPE (arg0), arg1));
3753 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
3756 if (TREE_CODE_CLASS (code) != tcc_comparison)
3759 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
3760 for neither. In real maths, we cannot assume open ended ranges are
3761 the same. But, this is computer arithmetic, where numbers are finite.
3762 We can therefore make the transformation of any unbounded range with
3763 the value Z, Z being greater than any representable number. This permits
3764 us to treat unbounded ranges as equal. */
3765 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
3766 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
3770 result = sgn0 == sgn1;
3773 result = sgn0 != sgn1;
3776 result = sgn0 < sgn1;
3779 result = sgn0 <= sgn1;
3782 result = sgn0 > sgn1;
3785 result = sgn0 >= sgn1;
3791 return constant_boolean_node (result, type);
3794 /* Given EXP, a logical expression, set the range it is testing into
3795 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
3796 actually being tested. *PLOW and *PHIGH will be made of the same
3797 type as the returned expression. If EXP is not a comparison, we
3798 will most likely not be returning a useful value and range. Set
3799 *STRICT_OVERFLOW_P to true if the return value is only valid
3800 because signed overflow is undefined; otherwise, do not change
3801 *STRICT_OVERFLOW_P. */
3804 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
3805 bool *strict_overflow_p)
3807 enum tree_code code;
3808 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
3809 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
3811 tree low, high, n_low, n_high;
3812 location_t loc = EXPR_LOCATION (exp);
3814 /* Start with simply saying "EXP != 0" and then look at the code of EXP
3815 and see if we can refine the range. Some of the cases below may not
3816 happen, but it doesn't seem worth worrying about this. We "continue"
3817 the outer loop when we've changed something; otherwise we "break"
3818 the switch, which will "break" the while. */
3821 low = high = build_int_cst (TREE_TYPE (exp), 0);
3825 code = TREE_CODE (exp);
3826 exp_type = TREE_TYPE (exp);
3828 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
3830 if (TREE_OPERAND_LENGTH (exp) > 0)
3831 arg0 = TREE_OPERAND (exp, 0);
3832 if (TREE_CODE_CLASS (code) == tcc_comparison
3833 || TREE_CODE_CLASS (code) == tcc_unary
3834 || TREE_CODE_CLASS (code) == tcc_binary)
3835 arg0_type = TREE_TYPE (arg0);
3836 if (TREE_CODE_CLASS (code) == tcc_binary
3837 || TREE_CODE_CLASS (code) == tcc_comparison
3838 || (TREE_CODE_CLASS (code) == tcc_expression
3839 && TREE_OPERAND_LENGTH (exp) > 1))
3840 arg1 = TREE_OPERAND (exp, 1);
3845 case TRUTH_NOT_EXPR:
3846 in_p = ! in_p, exp = arg0;
3849 case EQ_EXPR: case NE_EXPR:
3850 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
3851 /* We can only do something if the range is testing for zero
3852 and if the second operand is an integer constant. Note that
3853 saying something is "in" the range we make is done by
3854 complementing IN_P since it will set in the initial case of
3855 being not equal to zero; "out" is leaving it alone. */
3856 if (low == 0 || high == 0
3857 || ! integer_zerop (low) || ! integer_zerop (high)
3858 || TREE_CODE (arg1) != INTEGER_CST)
3863 case NE_EXPR: /* - [c, c] */
3866 case EQ_EXPR: /* + [c, c] */
3867 in_p = ! in_p, low = high = arg1;
3869 case GT_EXPR: /* - [-, c] */
3870 low = 0, high = arg1;
3872 case GE_EXPR: /* + [c, -] */
3873 in_p = ! in_p, low = arg1, high = 0;
3875 case LT_EXPR: /* - [c, -] */
3876 low = arg1, high = 0;
3878 case LE_EXPR: /* + [-, c] */
3879 in_p = ! in_p, low = 0, high = arg1;
3885 /* If this is an unsigned comparison, we also know that EXP is
3886 greater than or equal to zero. We base the range tests we make
3887 on that fact, so we record it here so we can parse existing
3888 range tests. We test arg0_type since often the return type
3889 of, e.g. EQ_EXPR, is boolean. */
3890 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
3892 if (! merge_ranges (&n_in_p, &n_low, &n_high,
3894 build_int_cst (arg0_type, 0),
3898 in_p = n_in_p, low = n_low, high = n_high;
3900 /* If the high bound is missing, but we have a nonzero low
3901 bound, reverse the range so it goes from zero to the low bound
3903 if (high == 0 && low && ! integer_zerop (low))
3906 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
3907 integer_one_node, 0);
3908 low = build_int_cst (arg0_type, 0);
3916 /* (-x) IN [a,b] -> x in [-b, -a] */
3917 n_low = range_binop (MINUS_EXPR, exp_type,
3918 build_int_cst (exp_type, 0),
3920 n_high = range_binop (MINUS_EXPR, exp_type,
3921 build_int_cst (exp_type, 0),
3923 if (n_high != 0 && TREE_OVERFLOW (n_high))
3929 exp = build2_loc (loc, MINUS_EXPR, exp_type, negate_expr (arg0),
3930 build_int_cst (exp_type, 1));
3933 case PLUS_EXPR: case MINUS_EXPR:
3934 if (TREE_CODE (arg1) != INTEGER_CST)
3937 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
3938 move a constant to the other side. */
3939 if (!TYPE_UNSIGNED (arg0_type)
3940 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
3943 /* If EXP is signed, any overflow in the computation is undefined,
3944 so we don't worry about it so long as our computations on
3945 the bounds don't overflow. For unsigned, overflow is defined
3946 and this is exactly the right thing. */
3947 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
3948 arg0_type, low, 0, arg1, 0);
3949 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
3950 arg0_type, high, 1, arg1, 0);
3951 if ((n_low != 0 && TREE_OVERFLOW (n_low))
3952 || (n_high != 0 && TREE_OVERFLOW (n_high)))
3955 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
3956 *strict_overflow_p = true;
3959 /* Check for an unsigned range which has wrapped around the maximum
3960 value thus making n_high < n_low, and normalize it. */
3961 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
3963 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
3964 integer_one_node, 0);
3965 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
3966 integer_one_node, 0);
3968 /* If the range is of the form +/- [ x+1, x ], we won't
3969 be able to normalize it. But then, it represents the
3970 whole range or the empty set, so make it
3972 if (tree_int_cst_equal (n_low, low)
3973 && tree_int_cst_equal (n_high, high))
3979 low = n_low, high = n_high;
3984 CASE_CONVERT: case NON_LVALUE_EXPR:
3985 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
3988 if (! INTEGRAL_TYPE_P (arg0_type)
3989 || (low != 0 && ! int_fits_type_p (low, arg0_type))
3990 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
3993 n_low = low, n_high = high;
3996 n_low = fold_convert_loc (loc, arg0_type, n_low);
3999 n_high = fold_convert_loc (loc, arg0_type, n_high);
4002 /* If we're converting arg0 from an unsigned type, to exp,
4003 a signed type, we will be doing the comparison as unsigned.
4004 The tests above have already verified that LOW and HIGH
4007 So we have to ensure that we will handle large unsigned
4008 values the same way that the current signed bounds treat
4011 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4015 /* For fixed-point modes, we need to pass the saturating flag
4016 as the 2nd parameter. */
4017 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4018 equiv_type = lang_hooks.types.type_for_mode
4019 (TYPE_MODE (arg0_type),
4020 TYPE_SATURATING (arg0_type));
4022 equiv_type = lang_hooks.types.type_for_mode
4023 (TYPE_MODE (arg0_type), 1);
4025 /* A range without an upper bound is, naturally, unbounded.
4026 Since convert would have cropped a very large value, use
4027 the max value for the destination type. */
4029 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4030 : TYPE_MAX_VALUE (arg0_type);
4032 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4033 high_positive = fold_build2_loc (loc, RSHIFT_EXPR, arg0_type,
4034 fold_convert_loc (loc, arg0_type,
4036 build_int_cst (arg0_type, 1));
4038 /* If the low bound is specified, "and" the range with the
4039 range for which the original unsigned value will be
4043 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4044 1, n_low, n_high, 1,
4045 fold_convert_loc (loc, arg0_type,
4050 in_p = (n_in_p == in_p);
4054 /* Otherwise, "or" the range with the range of the input
4055 that will be interpreted as negative. */
4056 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4057 0, n_low, n_high, 1,
4058 fold_convert_loc (loc, arg0_type,
4063 in_p = (in_p != n_in_p);
4068 low = n_low, high = n_high;
4078 /* If EXP is a constant, we can evaluate whether this is true or false. */
4079 if (TREE_CODE (exp) == INTEGER_CST)
4081 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4083 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4089 *pin_p = in_p, *plow = low, *phigh = high;
4093 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4094 type, TYPE, return an expression to test if EXP is in (or out of, depending
4095 on IN_P) the range. Return 0 if the test couldn't be created. */
4098 build_range_check (location_t loc, tree type, tree exp, int in_p,
4099 tree low, tree high)
4101 tree etype = TREE_TYPE (exp), value;
4103 #ifdef HAVE_canonicalize_funcptr_for_compare
4104 /* Disable this optimization for function pointer expressions
4105 on targets that require function pointer canonicalization. */
4106 if (HAVE_canonicalize_funcptr_for_compare
4107 && TREE_CODE (etype) == POINTER_TYPE
4108 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4114 value = build_range_check (loc, type, exp, 1, low, high);
4116 return invert_truthvalue_loc (loc, value);
4121 if (low == 0 && high == 0)
4122 return build_int_cst (type, 1);
4125 return fold_build2_loc (loc, LE_EXPR, type, exp,
4126 fold_convert_loc (loc, etype, high));
4129 return fold_build2_loc (loc, GE_EXPR, type, exp,
4130 fold_convert_loc (loc, etype, low));
4132 if (operand_equal_p (low, high, 0))
4133 return fold_build2_loc (loc, EQ_EXPR, type, exp,
4134 fold_convert_loc (loc, etype, low));
4136 if (integer_zerop (low))
4138 if (! TYPE_UNSIGNED (etype))
4140 etype = unsigned_type_for (etype);
4141 high = fold_convert_loc (loc, etype, high);
4142 exp = fold_convert_loc (loc, etype, exp);
4144 return build_range_check (loc, type, exp, 1, 0, high);
4147 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4148 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4150 unsigned HOST_WIDE_INT lo;
4154 prec = TYPE_PRECISION (etype);
4155 if (prec <= HOST_BITS_PER_WIDE_INT)
4158 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4162 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4163 lo = (unsigned HOST_WIDE_INT) -1;
4166 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4168 if (TYPE_UNSIGNED (etype))
4170 tree signed_etype = signed_type_for (etype);
4171 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4173 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4175 etype = signed_etype;
4176 exp = fold_convert_loc (loc, etype, exp);
4178 return fold_build2_loc (loc, GT_EXPR, type, exp,
4179 build_int_cst (etype, 0));
4183 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4184 This requires wrap-around arithmetics for the type of the expression.
4185 First make sure that arithmetics in this type is valid, then make sure
4186 that it wraps around. */
4187 if (TREE_CODE (etype) == ENUMERAL_TYPE || TREE_CODE (etype) == BOOLEAN_TYPE)
4188 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4189 TYPE_UNSIGNED (etype));
4191 if (TREE_CODE (etype) == INTEGER_TYPE && !TYPE_OVERFLOW_WRAPS (etype))
4193 tree utype, minv, maxv;
4195 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4196 for the type in question, as we rely on this here. */
4197 utype = unsigned_type_for (etype);
4198 maxv = fold_convert_loc (loc, utype, TYPE_MAX_VALUE (etype));
4199 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4200 integer_one_node, 1);
4201 minv = fold_convert_loc (loc, utype, TYPE_MIN_VALUE (etype));
4203 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4210 high = fold_convert_loc (loc, etype, high);
4211 low = fold_convert_loc (loc, etype, low);
4212 exp = fold_convert_loc (loc, etype, exp);
4214 value = const_binop (MINUS_EXPR, high, low);
4217 if (POINTER_TYPE_P (etype))
4219 if (value != 0 && !TREE_OVERFLOW (value))
4221 low = fold_convert_loc (loc, sizetype, low);
4222 low = fold_build1_loc (loc, NEGATE_EXPR, sizetype, low);
4223 return build_range_check (loc, type,
4224 fold_build2_loc (loc, POINTER_PLUS_EXPR,
4226 1, build_int_cst (etype, 0), value);
4231 if (value != 0 && !TREE_OVERFLOW (value))
4232 return build_range_check (loc, type,
4233 fold_build2_loc (loc, MINUS_EXPR, etype, exp, low),
4234 1, build_int_cst (etype, 0), value);
4239 /* Return the predecessor of VAL in its type, handling the infinite case. */
4242 range_predecessor (tree val)
4244 tree type = TREE_TYPE (val);
4246 if (INTEGRAL_TYPE_P (type)
4247 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4250 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4253 /* Return the successor of VAL in its type, handling the infinite case. */
4256 range_successor (tree val)
4258 tree type = TREE_TYPE (val);
4260 if (INTEGRAL_TYPE_P (type)
4261 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4264 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4267 /* Given two ranges, see if we can merge them into one. Return 1 if we
4268 can, 0 if we can't. Set the output range into the specified parameters. */
4271 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4272 tree high0, int in1_p, tree low1, tree high1)
4280 int lowequal = ((low0 == 0 && low1 == 0)
4281 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4282 low0, 0, low1, 0)));
4283 int highequal = ((high0 == 0 && high1 == 0)
4284 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4285 high0, 1, high1, 1)));
4287 /* Make range 0 be the range that starts first, or ends last if they
4288 start at the same value. Swap them if it isn't. */
4289 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4292 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4293 high1, 1, high0, 1))))
4295 temp = in0_p, in0_p = in1_p, in1_p = temp;
4296 tem = low0, low0 = low1, low1 = tem;
4297 tem = high0, high0 = high1, high1 = tem;
4300 /* Now flag two cases, whether the ranges are disjoint or whether the
4301 second range is totally subsumed in the first. Note that the tests
4302 below are simplified by the ones above. */
4303 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4304 high0, 1, low1, 0));
4305 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4306 high1, 1, high0, 1));
4308 /* We now have four cases, depending on whether we are including or
4309 excluding the two ranges. */
4312 /* If they don't overlap, the result is false. If the second range
4313 is a subset it is the result. Otherwise, the range is from the start
4314 of the second to the end of the first. */
4316 in_p = 0, low = high = 0;
4318 in_p = 1, low = low1, high = high1;
4320 in_p = 1, low = low1, high = high0;
4323 else if (in0_p && ! in1_p)
4325 /* If they don't overlap, the result is the first range. If they are
4326 equal, the result is false. If the second range is a subset of the
4327 first, and the ranges begin at the same place, we go from just after
4328 the end of the second range to the end of the first. If the second
4329 range is not a subset of the first, or if it is a subset and both
4330 ranges end at the same place, the range starts at the start of the
4331 first range and ends just before the second range.
4332 Otherwise, we can't describe this as a single range. */
4334 in_p = 1, low = low0, high = high0;
4335 else if (lowequal && highequal)
4336 in_p = 0, low = high = 0;
4337 else if (subset && lowequal)
4339 low = range_successor (high1);
4344 /* We are in the weird situation where high0 > high1 but
4345 high1 has no successor. Punt. */
4349 else if (! subset || highequal)
4352 high = range_predecessor (low1);
4356 /* low0 < low1 but low1 has no predecessor. Punt. */
4364 else if (! in0_p && in1_p)
4366 /* If they don't overlap, the result is the second range. If the second
4367 is a subset of the first, the result is false. Otherwise,
4368 the range starts just after the first range and ends at the
4369 end of the second. */
4371 in_p = 1, low = low1, high = high1;
4372 else if (subset || highequal)
4373 in_p = 0, low = high = 0;
4376 low = range_successor (high0);
4381 /* high1 > high0 but high0 has no successor. Punt. */
4389 /* The case where we are excluding both ranges. Here the complex case
4390 is if they don't overlap. In that case, the only time we have a
4391 range is if they are adjacent. If the second is a subset of the
4392 first, the result is the first. Otherwise, the range to exclude
4393 starts at the beginning of the first range and ends at the end of the
4397 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4398 range_successor (high0),
4400 in_p = 0, low = low0, high = high1;
4403 /* Canonicalize - [min, x] into - [-, x]. */
4404 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4405 switch (TREE_CODE (TREE_TYPE (low0)))
4408 if (TYPE_PRECISION (TREE_TYPE (low0))
4409 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
4413 if (tree_int_cst_equal (low0,
4414 TYPE_MIN_VALUE (TREE_TYPE (low0))))
4418 if (TYPE_UNSIGNED (TREE_TYPE (low0))
4419 && integer_zerop (low0))
4426 /* Canonicalize - [x, max] into - [x, -]. */
4427 if (high1 && TREE_CODE (high1) == INTEGER_CST)
4428 switch (TREE_CODE (TREE_TYPE (high1)))
4431 if (TYPE_PRECISION (TREE_TYPE (high1))
4432 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
4436 if (tree_int_cst_equal (high1,
4437 TYPE_MAX_VALUE (TREE_TYPE (high1))))
4441 if (TYPE_UNSIGNED (TREE_TYPE (high1))
4442 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
4444 integer_one_node, 1)))
4451 /* The ranges might be also adjacent between the maximum and
4452 minimum values of the given type. For
4453 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4454 return + [x + 1, y - 1]. */
4455 if (low0 == 0 && high1 == 0)
4457 low = range_successor (high0);
4458 high = range_predecessor (low1);
4459 if (low == 0 || high == 0)
4469 in_p = 0, low = low0, high = high0;
4471 in_p = 0, low = low0, high = high1;
4474 *pin_p = in_p, *plow = low, *phigh = high;
4479 /* Subroutine of fold, looking inside expressions of the form
4480 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
4481 of the COND_EXPR. This function is being used also to optimize
4482 A op B ? C : A, by reversing the comparison first.
4484 Return a folded expression whose code is not a COND_EXPR
4485 anymore, or NULL_TREE if no folding opportunity is found. */
4488 fold_cond_expr_with_comparison (location_t loc, tree type,
4489 tree arg0, tree arg1, tree arg2)
4491 enum tree_code comp_code = TREE_CODE (arg0);
4492 tree arg00 = TREE_OPERAND (arg0, 0);
4493 tree arg01 = TREE_OPERAND (arg0, 1);
4494 tree arg1_type = TREE_TYPE (arg1);
4500 /* If we have A op 0 ? A : -A, consider applying the following
4503 A == 0? A : -A same as -A
4504 A != 0? A : -A same as A
4505 A >= 0? A : -A same as abs (A)
4506 A > 0? A : -A same as abs (A)
4507 A <= 0? A : -A same as -abs (A)
4508 A < 0? A : -A same as -abs (A)
4510 None of these transformations work for modes with signed
4511 zeros. If A is +/-0, the first two transformations will
4512 change the sign of the result (from +0 to -0, or vice
4513 versa). The last four will fix the sign of the result,
4514 even though the original expressions could be positive or
4515 negative, depending on the sign of A.
4517 Note that all these transformations are correct if A is
4518 NaN, since the two alternatives (A and -A) are also NaNs. */
4519 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4520 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
4521 ? real_zerop (arg01)
4522 : integer_zerop (arg01))
4523 && ((TREE_CODE (arg2) == NEGATE_EXPR
4524 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
4525 /* In the case that A is of the form X-Y, '-A' (arg2) may
4526 have already been folded to Y-X, check for that. */
4527 || (TREE_CODE (arg1) == MINUS_EXPR
4528 && TREE_CODE (arg2) == MINUS_EXPR
4529 && operand_equal_p (TREE_OPERAND (arg1, 0),
4530 TREE_OPERAND (arg2, 1), 0)
4531 && operand_equal_p (TREE_OPERAND (arg1, 1),
4532 TREE_OPERAND (arg2, 0), 0))))
4537 tem = fold_convert_loc (loc, arg1_type, arg1);
4538 return pedantic_non_lvalue_loc (loc,
4539 fold_convert_loc (loc, type,
4540 negate_expr (tem)));
4543 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4546 if (flag_trapping_math)
4551 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4552 arg1 = fold_convert_loc (loc, signed_type_for
4553 (TREE_TYPE (arg1)), arg1);
4554 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4555 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4558 if (flag_trapping_math)
4562 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4563 arg1 = fold_convert_loc (loc, signed_type_for
4564 (TREE_TYPE (arg1)), arg1);
4565 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4566 return negate_expr (fold_convert_loc (loc, type, tem));
4568 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4572 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
4573 A == 0 ? A : 0 is always 0 unless A is -0. Note that
4574 both transformations are correct when A is NaN: A != 0
4575 is then true, and A == 0 is false. */
4577 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4578 && integer_zerop (arg01) && integer_zerop (arg2))
4580 if (comp_code == NE_EXPR)
4581 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4582 else if (comp_code == EQ_EXPR)
4583 return build_int_cst (type, 0);
4586 /* Try some transformations of A op B ? A : B.
4588 A == B? A : B same as B
4589 A != B? A : B same as A
4590 A >= B? A : B same as max (A, B)
4591 A > B? A : B same as max (B, A)
4592 A <= B? A : B same as min (A, B)
4593 A < B? A : B same as min (B, A)
4595 As above, these transformations don't work in the presence
4596 of signed zeros. For example, if A and B are zeros of
4597 opposite sign, the first two transformations will change
4598 the sign of the result. In the last four, the original
4599 expressions give different results for (A=+0, B=-0) and
4600 (A=-0, B=+0), but the transformed expressions do not.
4602 The first two transformations are correct if either A or B
4603 is a NaN. In the first transformation, the condition will
4604 be false, and B will indeed be chosen. In the case of the
4605 second transformation, the condition A != B will be true,
4606 and A will be chosen.
4608 The conversions to max() and min() are not correct if B is
4609 a number and A is not. The conditions in the original
4610 expressions will be false, so all four give B. The min()
4611 and max() versions would give a NaN instead. */
4612 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4613 && operand_equal_for_comparison_p (arg01, arg2, arg00)
4614 /* Avoid these transformations if the COND_EXPR may be used
4615 as an lvalue in the C++ front-end. PR c++/19199. */
4617 || (strcmp (lang_hooks.name, "GNU C++") != 0
4618 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
4619 || ! maybe_lvalue_p (arg1)
4620 || ! maybe_lvalue_p (arg2)))
4622 tree comp_op0 = arg00;
4623 tree comp_op1 = arg01;
4624 tree comp_type = TREE_TYPE (comp_op0);
4626 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
4627 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
4637 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg2));
4639 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4644 /* In C++ a ?: expression can be an lvalue, so put the
4645 operand which will be used if they are equal first
4646 so that we can convert this back to the
4647 corresponding COND_EXPR. */
4648 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4650 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4651 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4652 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
4653 ? fold_build2_loc (loc, MIN_EXPR, comp_type, comp_op0, comp_op1)
4654 : fold_build2_loc (loc, MIN_EXPR, comp_type,
4655 comp_op1, comp_op0);
4656 return pedantic_non_lvalue_loc (loc,
4657 fold_convert_loc (loc, type, tem));
4664 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4666 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4667 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4668 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
4669 ? fold_build2_loc (loc, MAX_EXPR, comp_type, comp_op0, comp_op1)
4670 : fold_build2_loc (loc, MAX_EXPR, comp_type,
4671 comp_op1, comp_op0);
4672 return pedantic_non_lvalue_loc (loc,
4673 fold_convert_loc (loc, type, tem));
4677 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4678 return pedantic_non_lvalue_loc (loc,
4679 fold_convert_loc (loc, type, arg2));
4682 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4683 return pedantic_non_lvalue_loc (loc,
4684 fold_convert_loc (loc, type, arg1));
4687 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4692 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
4693 we might still be able to simplify this. For example,
4694 if C1 is one less or one more than C2, this might have started
4695 out as a MIN or MAX and been transformed by this function.
4696 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
4698 if (INTEGRAL_TYPE_P (type)
4699 && TREE_CODE (arg01) == INTEGER_CST
4700 && TREE_CODE (arg2) == INTEGER_CST)
4704 if (TREE_CODE (arg1) == INTEGER_CST)
4706 /* We can replace A with C1 in this case. */
4707 arg1 = fold_convert_loc (loc, type, arg01);
4708 return fold_build3_loc (loc, COND_EXPR, type, arg0, arg1, arg2);
4711 /* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
4712 MIN_EXPR, to preserve the signedness of the comparison. */
4713 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4715 && operand_equal_p (arg01,
4716 const_binop (PLUS_EXPR, arg2,
4717 build_int_cst (type, 1)),
4720 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4721 fold_convert_loc (loc, TREE_TYPE (arg00),
4723 return pedantic_non_lvalue_loc (loc,
4724 fold_convert_loc (loc, type, tem));
4729 /* If C1 is C2 - 1, this is min(A, C2), with the same care
4731 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4733 && operand_equal_p (arg01,
4734 const_binop (MINUS_EXPR, arg2,
4735 build_int_cst (type, 1)),
4738 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4739 fold_convert_loc (loc, TREE_TYPE (arg00),
4741 return pedantic_non_lvalue_loc (loc,
4742 fold_convert_loc (loc, type, tem));
4747 /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for
4748 MAX_EXPR, to preserve the signedness of the comparison. */
4749 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4751 && operand_equal_p (arg01,
4752 const_binop (MINUS_EXPR, arg2,
4753 build_int_cst (type, 1)),
4756 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4757 fold_convert_loc (loc, TREE_TYPE (arg00),
4759 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4764 /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */
4765 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4767 && operand_equal_p (arg01,
4768 const_binop (PLUS_EXPR, arg2,
4769 build_int_cst (type, 1)),
4772 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4773 fold_convert_loc (loc, TREE_TYPE (arg00),
4775 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4789 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
4790 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
4791 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
4795 /* EXP is some logical combination of boolean tests. See if we can
4796 merge it into some range test. Return the new tree if so. */
4799 fold_range_test (location_t loc, enum tree_code code, tree type,
4802 int or_op = (code == TRUTH_ORIF_EXPR
4803 || code == TRUTH_OR_EXPR);
4804 int in0_p, in1_p, in_p;
4805 tree low0, low1, low, high0, high1, high;
4806 bool strict_overflow_p = false;
4807 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
4808 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
4810 const char * const warnmsg = G_("assuming signed overflow does not occur "
4811 "when simplifying range test");
4813 /* If this is an OR operation, invert both sides; we will invert
4814 again at the end. */
4816 in0_p = ! in0_p, in1_p = ! in1_p;
4818 /* If both expressions are the same, if we can merge the ranges, and we
4819 can build the range test, return it or it inverted. If one of the
4820 ranges is always true or always false, consider it to be the same
4821 expression as the other. */
4822 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
4823 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
4825 && 0 != (tem = (build_range_check (loc, type,
4827 : rhs != 0 ? rhs : integer_zero_node,
4830 if (strict_overflow_p)
4831 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
4832 return or_op ? invert_truthvalue_loc (loc, tem) : tem;
4835 /* On machines where the branch cost is expensive, if this is a
4836 short-circuited branch and the underlying object on both sides
4837 is the same, make a non-short-circuit operation. */
4838 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
4839 && lhs != 0 && rhs != 0
4840 && (code == TRUTH_ANDIF_EXPR
4841 || code == TRUTH_ORIF_EXPR)
4842 && operand_equal_p (lhs, rhs, 0))
4844 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
4845 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
4846 which cases we can't do this. */
4847 if (simple_operand_p (lhs))
4848 return build2_loc (loc, code == TRUTH_ANDIF_EXPR
4849 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4852 else if (!lang_hooks.decls.global_bindings_p ()
4853 && !CONTAINS_PLACEHOLDER_P (lhs))
4855 tree common = save_expr (lhs);
4857 if (0 != (lhs = build_range_check (loc, type, common,
4858 or_op ? ! in0_p : in0_p,
4860 && (0 != (rhs = build_range_check (loc, type, common,
4861 or_op ? ! in1_p : in1_p,
4864 if (strict_overflow_p)
4865 fold_overflow_warning (warnmsg,
4866 WARN_STRICT_OVERFLOW_COMPARISON);
4867 return build2_loc (loc, code == TRUTH_ANDIF_EXPR
4868 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4877 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
4878 bit value. Arrange things so the extra bits will be set to zero if and
4879 only if C is signed-extended to its full width. If MASK is nonzero,
4880 it is an INTEGER_CST that should be AND'ed with the extra bits. */
4883 unextend (tree c, int p, int unsignedp, tree mask)
4885 tree type = TREE_TYPE (c);
4886 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
4889 if (p == modesize || unsignedp)
4892 /* We work by getting just the sign bit into the low-order bit, then
4893 into the high-order bit, then sign-extend. We then XOR that value
4895 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1));
4896 temp = const_binop (BIT_AND_EXPR, temp, size_int (1));
4898 /* We must use a signed type in order to get an arithmetic right shift.
4899 However, we must also avoid introducing accidental overflows, so that
4900 a subsequent call to integer_zerop will work. Hence we must
4901 do the type conversion here. At this point, the constant is either
4902 zero or one, and the conversion to a signed type can never overflow.
4903 We could get an overflow if this conversion is done anywhere else. */
4904 if (TYPE_UNSIGNED (type))
4905 temp = fold_convert (signed_type_for (type), temp);
4907 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1));
4908 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1));
4910 temp = const_binop (BIT_AND_EXPR, temp,
4911 fold_convert (TREE_TYPE (c), mask));
4912 /* If necessary, convert the type back to match the type of C. */
4913 if (TYPE_UNSIGNED (type))
4914 temp = fold_convert (type, temp);
4916 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp));
4919 /* For an expression that has the form
4923 we can drop one of the inner expressions and simplify to
4927 LOC is the location of the resulting expression. OP is the inner
4928 logical operation; the left-hand side in the examples above, while CMPOP
4929 is the right-hand side. RHS_ONLY is used to prevent us from accidentally
4930 removing a condition that guards another, as in
4931 (A != NULL && A->...) || A == NULL
4932 which we must not transform. If RHS_ONLY is true, only eliminate the
4933 right-most operand of the inner logical operation. */
4936 merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop,
4939 tree type = TREE_TYPE (cmpop);
4940 enum tree_code code = TREE_CODE (cmpop);
4941 enum tree_code truthop_code = TREE_CODE (op);
4942 tree lhs = TREE_OPERAND (op, 0);
4943 tree rhs = TREE_OPERAND (op, 1);
4944 tree orig_lhs = lhs, orig_rhs = rhs;
4945 enum tree_code rhs_code = TREE_CODE (rhs);
4946 enum tree_code lhs_code = TREE_CODE (lhs);
4947 enum tree_code inv_code;
4949 if (TREE_SIDE_EFFECTS (op) || TREE_SIDE_EFFECTS (cmpop))
4952 if (TREE_CODE_CLASS (code) != tcc_comparison)
4955 if (rhs_code == truthop_code)
4957 tree newrhs = merge_truthop_with_opposite_arm (loc, rhs, cmpop, rhs_only);
4958 if (newrhs != NULL_TREE)
4961 rhs_code = TREE_CODE (rhs);
4964 if (lhs_code == truthop_code && !rhs_only)
4966 tree newlhs = merge_truthop_with_opposite_arm (loc, lhs, cmpop, false);
4967 if (newlhs != NULL_TREE)
4970 lhs_code = TREE_CODE (lhs);
4974 inv_code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (type)));
4975 if (inv_code == rhs_code
4976 && operand_equal_p (TREE_OPERAND (rhs, 0), TREE_OPERAND (cmpop, 0), 0)
4977 && operand_equal_p (TREE_OPERAND (rhs, 1), TREE_OPERAND (cmpop, 1), 0))
4979 if (!rhs_only && inv_code == lhs_code
4980 && operand_equal_p (TREE_OPERAND (lhs, 0), TREE_OPERAND (cmpop, 0), 0)
4981 && operand_equal_p (TREE_OPERAND (lhs, 1), TREE_OPERAND (cmpop, 1), 0))
4983 if (rhs != orig_rhs || lhs != orig_lhs)
4984 return fold_build2_loc (loc, truthop_code, TREE_TYPE (cmpop),
4989 /* Find ways of folding logical expressions of LHS and RHS:
4990 Try to merge two comparisons to the same innermost item.
4991 Look for range tests like "ch >= '0' && ch <= '9'".
4992 Look for combinations of simple terms on machines with expensive branches
4993 and evaluate the RHS unconditionally.
4995 For example, if we have p->a == 2 && p->b == 4 and we can make an
4996 object large enough to span both A and B, we can do this with a comparison
4997 against the object ANDed with the a mask.
4999 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5000 operations to do this with one comparison.
5002 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5003 function and the one above.
5005 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5006 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5008 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5011 We return the simplified tree or 0 if no optimization is possible. */
5014 fold_truthop (location_t loc, enum tree_code code, tree truth_type,
5017 /* If this is the "or" of two comparisons, we can do something if
5018 the comparisons are NE_EXPR. If this is the "and", we can do something
5019 if the comparisons are EQ_EXPR. I.e.,
5020 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5022 WANTED_CODE is this operation code. For single bit fields, we can
5023 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5024 comparison for one-bit fields. */
5026 enum tree_code wanted_code;
5027 enum tree_code lcode, rcode;
5028 tree ll_arg, lr_arg, rl_arg, rr_arg;
5029 tree ll_inner, lr_inner, rl_inner, rr_inner;
5030 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5031 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5032 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5033 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5034 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5035 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5036 enum machine_mode lnmode, rnmode;
5037 tree ll_mask, lr_mask, rl_mask, rr_mask;
5038 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5039 tree l_const, r_const;
5040 tree lntype, rntype, result;
5041 HOST_WIDE_INT first_bit, end_bit;
5043 tree orig_lhs = lhs, orig_rhs = rhs;
5044 enum tree_code orig_code = code;
5046 /* Start by getting the comparison codes. Fail if anything is volatile.
5047 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5048 it were surrounded with a NE_EXPR. */
5050 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5053 lcode = TREE_CODE (lhs);
5054 rcode = TREE_CODE (rhs);
5056 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5058 lhs = build2 (NE_EXPR, truth_type, lhs,
5059 build_int_cst (TREE_TYPE (lhs), 0));
5063 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5065 rhs = build2 (NE_EXPR, truth_type, rhs,
5066 build_int_cst (TREE_TYPE (rhs), 0));
5070 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5071 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5074 ll_arg = TREE_OPERAND (lhs, 0);
5075 lr_arg = TREE_OPERAND (lhs, 1);
5076 rl_arg = TREE_OPERAND (rhs, 0);
5077 rr_arg = TREE_OPERAND (rhs, 1);
5079 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5080 if (simple_operand_p (ll_arg)
5081 && simple_operand_p (lr_arg))
5083 if (operand_equal_p (ll_arg, rl_arg, 0)
5084 && operand_equal_p (lr_arg, rr_arg, 0))
5086 result = combine_comparisons (loc, code, lcode, rcode,
5087 truth_type, ll_arg, lr_arg);
5091 else if (operand_equal_p (ll_arg, rr_arg, 0)
5092 && operand_equal_p (lr_arg, rl_arg, 0))
5094 result = combine_comparisons (loc, code, lcode,
5095 swap_tree_comparison (rcode),
5096 truth_type, ll_arg, lr_arg);
5102 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5103 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5105 /* If the RHS can be evaluated unconditionally and its operands are
5106 simple, it wins to evaluate the RHS unconditionally on machines
5107 with expensive branches. In this case, this isn't a comparison
5108 that can be merged. Avoid doing this if the RHS is a floating-point
5109 comparison since those can trap. */
5111 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5113 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5114 && simple_operand_p (rl_arg)
5115 && simple_operand_p (rr_arg))
5117 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5118 if (code == TRUTH_OR_EXPR
5119 && lcode == NE_EXPR && integer_zerop (lr_arg)
5120 && rcode == NE_EXPR && integer_zerop (rr_arg)
5121 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5122 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5123 return build2_loc (loc, NE_EXPR, truth_type,
5124 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5126 build_int_cst (TREE_TYPE (ll_arg), 0));
5128 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5129 if (code == TRUTH_AND_EXPR
5130 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5131 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5132 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5133 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5134 return build2_loc (loc, EQ_EXPR, truth_type,
5135 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5137 build_int_cst (TREE_TYPE (ll_arg), 0));
5139 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5141 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5142 return build2_loc (loc, code, truth_type, lhs, rhs);
5147 /* See if the comparisons can be merged. Then get all the parameters for
5150 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5151 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5155 ll_inner = decode_field_reference (loc, ll_arg,
5156 &ll_bitsize, &ll_bitpos, &ll_mode,
5157 &ll_unsignedp, &volatilep, &ll_mask,
5159 lr_inner = decode_field_reference (loc, lr_arg,
5160 &lr_bitsize, &lr_bitpos, &lr_mode,
5161 &lr_unsignedp, &volatilep, &lr_mask,
5163 rl_inner = decode_field_reference (loc, rl_arg,
5164 &rl_bitsize, &rl_bitpos, &rl_mode,
5165 &rl_unsignedp, &volatilep, &rl_mask,
5167 rr_inner = decode_field_reference (loc, rr_arg,
5168 &rr_bitsize, &rr_bitpos, &rr_mode,
5169 &rr_unsignedp, &volatilep, &rr_mask,
5172 /* It must be true that the inner operation on the lhs of each
5173 comparison must be the same if we are to be able to do anything.
5174 Then see if we have constants. If not, the same must be true for
5176 if (volatilep || ll_inner == 0 || rl_inner == 0
5177 || ! operand_equal_p (ll_inner, rl_inner, 0))
5180 if (TREE_CODE (lr_arg) == INTEGER_CST
5181 && TREE_CODE (rr_arg) == INTEGER_CST)
5182 l_const = lr_arg, r_const = rr_arg;
5183 else if (lr_inner == 0 || rr_inner == 0
5184 || ! operand_equal_p (lr_inner, rr_inner, 0))
5187 l_const = r_const = 0;
5189 /* If either comparison code is not correct for our logical operation,
5190 fail. However, we can convert a one-bit comparison against zero into
5191 the opposite comparison against that bit being set in the field. */
5193 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5194 if (lcode != wanted_code)
5196 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5198 /* Make the left operand unsigned, since we are only interested
5199 in the value of one bit. Otherwise we are doing the wrong
5208 /* This is analogous to the code for l_const above. */
5209 if (rcode != wanted_code)
5211 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5220 /* See if we can find a mode that contains both fields being compared on
5221 the left. If we can't, fail. Otherwise, update all constants and masks
5222 to be relative to a field of that size. */
5223 first_bit = MIN (ll_bitpos, rl_bitpos);
5224 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5225 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5226 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5228 if (lnmode == VOIDmode)
5231 lnbitsize = GET_MODE_BITSIZE (lnmode);
5232 lnbitpos = first_bit & ~ (lnbitsize - 1);
5233 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5234 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5236 if (BYTES_BIG_ENDIAN)
5238 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5239 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5242 ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
5243 size_int (xll_bitpos));
5244 rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
5245 size_int (xrl_bitpos));
5249 l_const = fold_convert_loc (loc, lntype, l_const);
5250 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5251 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos));
5252 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5253 fold_build1_loc (loc, BIT_NOT_EXPR,
5256 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5258 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5263 r_const = fold_convert_loc (loc, lntype, r_const);
5264 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5265 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos));
5266 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5267 fold_build1_loc (loc, BIT_NOT_EXPR,
5270 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5272 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5276 /* If the right sides are not constant, do the same for it. Also,
5277 disallow this optimization if a size or signedness mismatch occurs
5278 between the left and right sides. */
5281 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
5282 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
5283 /* Make sure the two fields on the right
5284 correspond to the left without being swapped. */
5285 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
5288 first_bit = MIN (lr_bitpos, rr_bitpos);
5289 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
5290 rnmode = get_best_mode (end_bit - first_bit, first_bit,
5291 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
5293 if (rnmode == VOIDmode)
5296 rnbitsize = GET_MODE_BITSIZE (rnmode);
5297 rnbitpos = first_bit & ~ (rnbitsize - 1);
5298 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
5299 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
5301 if (BYTES_BIG_ENDIAN)
5303 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
5304 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
5307 lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5309 size_int (xlr_bitpos));
5310 rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5312 size_int (xrr_bitpos));
5314 /* Make a mask that corresponds to both fields being compared.
5315 Do this for both items being compared. If the operands are the
5316 same size and the bits being compared are in the same position
5317 then we can do this by masking both and comparing the masked
5319 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5320 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask);
5321 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
5323 lhs = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5324 ll_unsignedp || rl_unsignedp);
5325 if (! all_ones_mask_p (ll_mask, lnbitsize))
5326 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
5328 rhs = make_bit_field_ref (loc, lr_inner, rntype, rnbitsize, rnbitpos,
5329 lr_unsignedp || rr_unsignedp);
5330 if (! all_ones_mask_p (lr_mask, rnbitsize))
5331 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
5333 return build2_loc (loc, wanted_code, truth_type, lhs, rhs);
5336 /* There is still another way we can do something: If both pairs of
5337 fields being compared are adjacent, we may be able to make a wider
5338 field containing them both.
5340 Note that we still must mask the lhs/rhs expressions. Furthermore,
5341 the mask must be shifted to account for the shift done by
5342 make_bit_field_ref. */
5343 if ((ll_bitsize + ll_bitpos == rl_bitpos
5344 && lr_bitsize + lr_bitpos == rr_bitpos)
5345 || (ll_bitpos == rl_bitpos + rl_bitsize
5346 && lr_bitpos == rr_bitpos + rr_bitsize))
5350 lhs = make_bit_field_ref (loc, ll_inner, lntype,
5351 ll_bitsize + rl_bitsize,
5352 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
5353 rhs = make_bit_field_ref (loc, lr_inner, rntype,
5354 lr_bitsize + rr_bitsize,
5355 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
5357 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
5358 size_int (MIN (xll_bitpos, xrl_bitpos)));
5359 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
5360 size_int (MIN (xlr_bitpos, xrr_bitpos)));
5362 /* Convert to the smaller type before masking out unwanted bits. */
5364 if (lntype != rntype)
5366 if (lnbitsize > rnbitsize)
5368 lhs = fold_convert_loc (loc, rntype, lhs);
5369 ll_mask = fold_convert_loc (loc, rntype, ll_mask);
5372 else if (lnbitsize < rnbitsize)
5374 rhs = fold_convert_loc (loc, lntype, rhs);
5375 lr_mask = fold_convert_loc (loc, lntype, lr_mask);
5380 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
5381 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
5383 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
5384 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
5386 return build2_loc (loc, wanted_code, truth_type, lhs, rhs);
5392 /* Handle the case of comparisons with constants. If there is something in
5393 common between the masks, those bits of the constants must be the same.
5394 If not, the condition is always false. Test for this to avoid generating
5395 incorrect code below. */
5396 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask);
5397 if (! integer_zerop (result)
5398 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const),
5399 const_binop (BIT_AND_EXPR, result, r_const)) != 1)
5401 if (wanted_code == NE_EXPR)
5403 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5404 return constant_boolean_node (true, truth_type);
5408 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5409 return constant_boolean_node (false, truth_type);
5413 /* Construct the expression we will return. First get the component
5414 reference we will make. Unless the mask is all ones the width of
5415 that field, perform the mask operation. Then compare with the
5417 result = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5418 ll_unsignedp || rl_unsignedp);
5420 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5421 if (! all_ones_mask_p (ll_mask, lnbitsize))
5422 result = build2_loc (loc, BIT_AND_EXPR, lntype, result, ll_mask);
5424 return build2_loc (loc, wanted_code, truth_type, result,
5425 const_binop (BIT_IOR_EXPR, l_const, r_const));
5428 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5432 optimize_minmax_comparison (location_t loc, enum tree_code code, tree type,
5436 enum tree_code op_code;
5439 int consts_equal, consts_lt;
5442 STRIP_SIGN_NOPS (arg0);
5444 op_code = TREE_CODE (arg0);
5445 minmax_const = TREE_OPERAND (arg0, 1);
5446 comp_const = fold_convert_loc (loc, TREE_TYPE (arg0), op1);
5447 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5448 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5449 inner = TREE_OPERAND (arg0, 0);
5451 /* If something does not permit us to optimize, return the original tree. */
5452 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5453 || TREE_CODE (comp_const) != INTEGER_CST
5454 || TREE_OVERFLOW (comp_const)
5455 || TREE_CODE (minmax_const) != INTEGER_CST
5456 || TREE_OVERFLOW (minmax_const))
5459 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5460 and GT_EXPR, doing the rest with recursive calls using logical
5464 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5467 = optimize_minmax_comparison (loc,
5468 invert_tree_comparison (code, false),
5471 return invert_truthvalue_loc (loc, tem);
5477 fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
5478 optimize_minmax_comparison
5479 (loc, EQ_EXPR, type, arg0, comp_const),
5480 optimize_minmax_comparison
5481 (loc, GT_EXPR, type, arg0, comp_const));
5484 if (op_code == MAX_EXPR && consts_equal)
5485 /* MAX (X, 0) == 0 -> X <= 0 */
5486 return fold_build2_loc (loc, LE_EXPR, type, inner, comp_const);
5488 else if (op_code == MAX_EXPR && consts_lt)
5489 /* MAX (X, 0) == 5 -> X == 5 */
5490 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5492 else if (op_code == MAX_EXPR)
5493 /* MAX (X, 0) == -1 -> false */
5494 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5496 else if (consts_equal)
5497 /* MIN (X, 0) == 0 -> X >= 0 */
5498 return fold_build2_loc (loc, GE_EXPR, type, inner, comp_const);
5501 /* MIN (X, 0) == 5 -> false */
5502 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5505 /* MIN (X, 0) == -1 -> X == -1 */
5506 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5509 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5510 /* MAX (X, 0) > 0 -> X > 0
5511 MAX (X, 0) > 5 -> X > 5 */
5512 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5514 else if (op_code == MAX_EXPR)
5515 /* MAX (X, 0) > -1 -> true */
5516 return omit_one_operand_loc (loc, type, integer_one_node, inner);
5518 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
5519 /* MIN (X, 0) > 0 -> false
5520 MIN (X, 0) > 5 -> false */
5521 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5524 /* MIN (X, 0) > -1 -> X > -1 */
5525 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5532 /* T is an integer expression that is being multiplied, divided, or taken a
5533 modulus (CODE says which and what kind of divide or modulus) by a
5534 constant C. See if we can eliminate that operation by folding it with
5535 other operations already in T. WIDE_TYPE, if non-null, is a type that
5536 should be used for the computation if wider than our type.
5538 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5539 (X * 2) + (Y * 4). We must, however, be assured that either the original
5540 expression would not overflow or that overflow is undefined for the type
5541 in the language in question.
5543 If we return a non-null expression, it is an equivalent form of the
5544 original computation, but need not be in the original type.
5546 We set *STRICT_OVERFLOW_P to true if the return values depends on
5547 signed overflow being undefined. Otherwise we do not change
5548 *STRICT_OVERFLOW_P. */
5551 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
5552 bool *strict_overflow_p)
5554 /* To avoid exponential search depth, refuse to allow recursion past
5555 three levels. Beyond that (1) it's highly unlikely that we'll find
5556 something interesting and (2) we've probably processed it before
5557 when we built the inner expression. */
5566 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
5573 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
5574 bool *strict_overflow_p)
5576 tree type = TREE_TYPE (t);
5577 enum tree_code tcode = TREE_CODE (t);
5578 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
5579 > GET_MODE_SIZE (TYPE_MODE (type)))
5580 ? wide_type : type);
5582 int same_p = tcode == code;
5583 tree op0 = NULL_TREE, op1 = NULL_TREE;
5584 bool sub_strict_overflow_p;
5586 /* Don't deal with constants of zero here; they confuse the code below. */
5587 if (integer_zerop (c))
5590 if (TREE_CODE_CLASS (tcode) == tcc_unary)
5591 op0 = TREE_OPERAND (t, 0);
5593 if (TREE_CODE_CLASS (tcode) == tcc_binary)
5594 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
5596 /* Note that we need not handle conditional operations here since fold
5597 already handles those cases. So just do arithmetic here. */
5601 /* For a constant, we can always simplify if we are a multiply
5602 or (for divide and modulus) if it is a multiple of our constant. */
5603 if (code == MULT_EXPR
5604 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c)))
5605 return const_binop (code, fold_convert (ctype, t),
5606 fold_convert (ctype, c));
5609 CASE_CONVERT: case NON_LVALUE_EXPR:
5610 /* If op0 is an expression ... */
5611 if ((COMPARISON_CLASS_P (op0)
5612 || UNARY_CLASS_P (op0)
5613 || BINARY_CLASS_P (op0)
5614 || VL_EXP_CLASS_P (op0)
5615 || EXPRESSION_CLASS_P (op0))
5616 /* ... and has wrapping overflow, and its type is smaller
5617 than ctype, then we cannot pass through as widening. */
5618 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
5619 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
5620 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
5621 && (TYPE_PRECISION (ctype)
5622 > TYPE_PRECISION (TREE_TYPE (op0))))
5623 /* ... or this is a truncation (t is narrower than op0),
5624 then we cannot pass through this narrowing. */
5625 || (TYPE_PRECISION (type)
5626 < TYPE_PRECISION (TREE_TYPE (op0)))
5627 /* ... or signedness changes for division or modulus,
5628 then we cannot pass through this conversion. */
5629 || (code != MULT_EXPR
5630 && (TYPE_UNSIGNED (ctype)
5631 != TYPE_UNSIGNED (TREE_TYPE (op0))))
5632 /* ... or has undefined overflow while the converted to
5633 type has not, we cannot do the operation in the inner type
5634 as that would introduce undefined overflow. */
5635 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
5636 && !TYPE_OVERFLOW_UNDEFINED (type))))
5639 /* Pass the constant down and see if we can make a simplification. If
5640 we can, replace this expression with the inner simplification for
5641 possible later conversion to our or some other type. */
5642 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
5643 && TREE_CODE (t2) == INTEGER_CST
5644 && !TREE_OVERFLOW (t2)
5645 && (0 != (t1 = extract_muldiv (op0, t2, code,
5647 ? ctype : NULL_TREE,
5648 strict_overflow_p))))
5653 /* If widening the type changes it from signed to unsigned, then we
5654 must avoid building ABS_EXPR itself as unsigned. */
5655 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
5657 tree cstype = (*signed_type_for) (ctype);
5658 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
5661 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
5662 return fold_convert (ctype, t1);
5666 /* If the constant is negative, we cannot simplify this. */
5667 if (tree_int_cst_sgn (c) == -1)
5671 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
5673 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
5676 case MIN_EXPR: case MAX_EXPR:
5677 /* If widening the type changes the signedness, then we can't perform
5678 this optimization as that changes the result. */
5679 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
5682 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
5683 sub_strict_overflow_p = false;
5684 if ((t1 = extract_muldiv (op0, c, code, wide_type,
5685 &sub_strict_overflow_p)) != 0
5686 && (t2 = extract_muldiv (op1, c, code, wide_type,
5687 &sub_strict_overflow_p)) != 0)
5689 if (tree_int_cst_sgn (c) < 0)
5690 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
5691 if (sub_strict_overflow_p)
5692 *strict_overflow_p = true;
5693 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5694 fold_convert (ctype, t2));
5698 case LSHIFT_EXPR: case RSHIFT_EXPR:
5699 /* If the second operand is constant, this is a multiplication
5700 or floor division, by a power of two, so we can treat it that
5701 way unless the multiplier or divisor overflows. Signed
5702 left-shift overflow is implementation-defined rather than
5703 undefined in C90, so do not convert signed left shift into
5705 if (TREE_CODE (op1) == INTEGER_CST
5706 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
5707 /* const_binop may not detect overflow correctly,
5708 so check for it explicitly here. */
5709 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
5710 && TREE_INT_CST_HIGH (op1) == 0
5711 && 0 != (t1 = fold_convert (ctype,
5712 const_binop (LSHIFT_EXPR,
5715 && !TREE_OVERFLOW (t1))
5716 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
5717 ? MULT_EXPR : FLOOR_DIV_EXPR,
5719 fold_convert (ctype, op0),
5721 c, code, wide_type, strict_overflow_p);
5724 case PLUS_EXPR: case MINUS_EXPR:
5725 /* See if we can eliminate the operation on both sides. If we can, we
5726 can return a new PLUS or MINUS. If we can't, the only remaining
5727 cases where we can do anything are if the second operand is a
5729 sub_strict_overflow_p = false;
5730 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
5731 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
5732 if (t1 != 0 && t2 != 0
5733 && (code == MULT_EXPR
5734 /* If not multiplication, we can only do this if both operands
5735 are divisible by c. */
5736 || (multiple_of_p (ctype, op0, c)
5737 && multiple_of_p (ctype, op1, c))))
5739 if (sub_strict_overflow_p)
5740 *strict_overflow_p = true;
5741 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5742 fold_convert (ctype, t2));
5745 /* If this was a subtraction, negate OP1 and set it to be an addition.
5746 This simplifies the logic below. */
5747 if (tcode == MINUS_EXPR)
5749 tcode = PLUS_EXPR, op1 = negate_expr (op1);
5750 /* If OP1 was not easily negatable, the constant may be OP0. */
5751 if (TREE_CODE (op0) == INTEGER_CST)
5762 if (TREE_CODE (op1) != INTEGER_CST)
5765 /* If either OP1 or C are negative, this optimization is not safe for
5766 some of the division and remainder types while for others we need
5767 to change the code. */
5768 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
5770 if (code == CEIL_DIV_EXPR)
5771 code = FLOOR_DIV_EXPR;
5772 else if (code == FLOOR_DIV_EXPR)
5773 code = CEIL_DIV_EXPR;
5774 else if (code != MULT_EXPR
5775 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
5779 /* If it's a multiply or a division/modulus operation of a multiple
5780 of our constant, do the operation and verify it doesn't overflow. */
5781 if (code == MULT_EXPR
5782 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5784 op1 = const_binop (code, fold_convert (ctype, op1),
5785 fold_convert (ctype, c));
5786 /* We allow the constant to overflow with wrapping semantics. */
5788 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
5794 /* If we have an unsigned type is not a sizetype, we cannot widen
5795 the operation since it will change the result if the original
5796 computation overflowed. */
5797 if (TYPE_UNSIGNED (ctype)
5798 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
5802 /* If we were able to eliminate our operation from the first side,
5803 apply our operation to the second side and reform the PLUS. */
5804 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
5805 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
5807 /* The last case is if we are a multiply. In that case, we can
5808 apply the distributive law to commute the multiply and addition
5809 if the multiplication of the constants doesn't overflow. */
5810 if (code == MULT_EXPR)
5811 return fold_build2 (tcode, ctype,
5812 fold_build2 (code, ctype,
5813 fold_convert (ctype, op0),
5814 fold_convert (ctype, c)),
5820 /* We have a special case here if we are doing something like
5821 (C * 8) % 4 since we know that's zero. */
5822 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
5823 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
5824 /* If the multiplication can overflow we cannot optimize this.
5825 ??? Until we can properly mark individual operations as
5826 not overflowing we need to treat sizetype special here as
5827 stor-layout relies on this opimization to make
5828 DECL_FIELD_BIT_OFFSET always a constant. */
5829 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
5830 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
5831 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
5832 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
5833 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5835 *strict_overflow_p = true;
5836 return omit_one_operand (type, integer_zero_node, op0);
5839 /* ... fall through ... */
5841 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
5842 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
5843 /* If we can extract our operation from the LHS, do so and return a
5844 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
5845 do something only if the second operand is a constant. */
5847 && (t1 = extract_muldiv (op0, c, code, wide_type,
5848 strict_overflow_p)) != 0)
5849 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5850 fold_convert (ctype, op1));
5851 else if (tcode == MULT_EXPR && code == MULT_EXPR
5852 && (t1 = extract_muldiv (op1, c, code, wide_type,
5853 strict_overflow_p)) != 0)
5854 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5855 fold_convert (ctype, t1));
5856 else if (TREE_CODE (op1) != INTEGER_CST)
5859 /* If these are the same operation types, we can associate them
5860 assuming no overflow. */
5865 mul = double_int_mul_with_sign
5867 (tree_to_double_int (op1),
5868 TYPE_PRECISION (ctype), TYPE_UNSIGNED (ctype)),
5870 (tree_to_double_int (c),
5871 TYPE_PRECISION (ctype), TYPE_UNSIGNED (ctype)),
5872 false, &overflow_p);
5873 overflow_p = (((!TYPE_UNSIGNED (ctype)
5874 || (TREE_CODE (ctype) == INTEGER_TYPE
5875 && TYPE_IS_SIZETYPE (ctype)))
5877 | TREE_OVERFLOW (c) | TREE_OVERFLOW (op1));
5878 if (!double_int_fits_to_tree_p (ctype, mul)
5879 && ((TYPE_UNSIGNED (ctype) && tcode != MULT_EXPR)
5880 || !TYPE_UNSIGNED (ctype)
5881 || (TREE_CODE (ctype) == INTEGER_TYPE
5882 && TYPE_IS_SIZETYPE (ctype))))
5885 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5886 double_int_to_tree (ctype, mul));
5889 /* If these operations "cancel" each other, we have the main
5890 optimizations of this pass, which occur when either constant is a
5891 multiple of the other, in which case we replace this with either an
5892 operation or CODE or TCODE.
5894 If we have an unsigned type that is not a sizetype, we cannot do
5895 this since it will change the result if the original computation
5897 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
5898 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
5899 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
5900 || (tcode == MULT_EXPR
5901 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
5902 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
5903 && code != MULT_EXPR)))
5905 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5907 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5908 *strict_overflow_p = true;
5909 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5910 fold_convert (ctype,
5911 const_binop (TRUNC_DIV_EXPR,
5914 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1)))
5916 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5917 *strict_overflow_p = true;
5918 return fold_build2 (code, ctype, fold_convert (ctype, op0),
5919 fold_convert (ctype,
5920 const_binop (TRUNC_DIV_EXPR,
5933 /* Return a node which has the indicated constant VALUE (either 0 or
5934 1), and is of the indicated TYPE. */
5937 constant_boolean_node (int value, tree type)
5939 if (type == integer_type_node)
5940 return value ? integer_one_node : integer_zero_node;
5941 else if (type == boolean_type_node)
5942 return value ? boolean_true_node : boolean_false_node;
5944 return build_int_cst (type, value);
5948 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
5949 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
5950 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
5951 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
5952 COND is the first argument to CODE; otherwise (as in the example
5953 given here), it is the second argument. TYPE is the type of the
5954 original expression. Return NULL_TREE if no simplification is
5958 fold_binary_op_with_conditional_arg (location_t loc,
5959 enum tree_code code,
5960 tree type, tree op0, tree op1,
5961 tree cond, tree arg, int cond_first_p)
5963 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
5964 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
5965 tree test, true_value, false_value;
5966 tree lhs = NULL_TREE;
5967 tree rhs = NULL_TREE;
5969 if (TREE_CODE (cond) == COND_EXPR)
5971 test = TREE_OPERAND (cond, 0);
5972 true_value = TREE_OPERAND (cond, 1);
5973 false_value = TREE_OPERAND (cond, 2);
5974 /* If this operand throws an expression, then it does not make
5975 sense to try to perform a logical or arithmetic operation
5977 if (VOID_TYPE_P (TREE_TYPE (true_value)))
5979 if (VOID_TYPE_P (TREE_TYPE (false_value)))
5984 tree testtype = TREE_TYPE (cond);
5986 true_value = constant_boolean_node (true, testtype);
5987 false_value = constant_boolean_node (false, testtype);
5990 /* This transformation is only worthwhile if we don't have to wrap ARG
5991 in a SAVE_EXPR and the operation can be simplified on at least one
5992 of the branches once its pushed inside the COND_EXPR. */
5993 if (!TREE_CONSTANT (arg)
5994 && (TREE_SIDE_EFFECTS (arg)
5995 || TREE_CONSTANT (true_value) || TREE_CONSTANT (false_value)))
5998 arg = fold_convert_loc (loc, arg_type, arg);
6001 true_value = fold_convert_loc (loc, cond_type, true_value);
6003 lhs = fold_build2_loc (loc, code, type, true_value, arg);
6005 lhs = fold_build2_loc (loc, code, type, arg, true_value);
6009 false_value = fold_convert_loc (loc, cond_type, false_value);
6011 rhs = fold_build2_loc (loc, code, type, false_value, arg);
6013 rhs = fold_build2_loc (loc, code, type, arg, false_value);
6016 /* Check that we have simplified at least one of the branches. */
6017 if (!TREE_CONSTANT (arg) && !TREE_CONSTANT (lhs) && !TREE_CONSTANT (rhs))
6020 return fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
6024 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6026 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6027 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6028 ADDEND is the same as X.
6030 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6031 and finite. The problematic cases are when X is zero, and its mode
6032 has signed zeros. In the case of rounding towards -infinity,
6033 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6034 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6037 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6039 if (!real_zerop (addend))
6042 /* Don't allow the fold with -fsignaling-nans. */
6043 if (HONOR_SNANS (TYPE_MODE (type)))
6046 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6047 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6050 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6051 if (TREE_CODE (addend) == REAL_CST
6052 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6055 /* The mode has signed zeros, and we have to honor their sign.
6056 In this situation, there is only one case we can return true for.
6057 X - 0 is the same as X unless rounding towards -infinity is
6059 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6062 /* Subroutine of fold() that checks comparisons of built-in math
6063 functions against real constants.
6065 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6066 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6067 is the type of the result and ARG0 and ARG1 are the operands of the
6068 comparison. ARG1 must be a TREE_REAL_CST.
6070 The function returns the constant folded tree if a simplification
6071 can be made, and NULL_TREE otherwise. */
6074 fold_mathfn_compare (location_t loc,
6075 enum built_in_function fcode, enum tree_code code,
6076 tree type, tree arg0, tree arg1)
6080 if (BUILTIN_SQRT_P (fcode))
6082 tree arg = CALL_EXPR_ARG (arg0, 0);
6083 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6085 c = TREE_REAL_CST (arg1);
6086 if (REAL_VALUE_NEGATIVE (c))
6088 /* sqrt(x) < y is always false, if y is negative. */
6089 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6090 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6092 /* sqrt(x) > y is always true, if y is negative and we
6093 don't care about NaNs, i.e. negative values of x. */
6094 if (code == NE_EXPR || !HONOR_NANS (mode))
6095 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6097 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6098 return fold_build2_loc (loc, GE_EXPR, type, arg,
6099 build_real (TREE_TYPE (arg), dconst0));
6101 else if (code == GT_EXPR || code == GE_EXPR)
6105 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6106 real_convert (&c2, mode, &c2);
6108 if (REAL_VALUE_ISINF (c2))
6110 /* sqrt(x) > y is x == +Inf, when y is very large. */
6111 if (HONOR_INFINITIES (mode))
6112 return fold_build2_loc (loc, EQ_EXPR, type, arg,
6113 build_real (TREE_TYPE (arg), c2));
6115 /* sqrt(x) > y is always false, when y is very large
6116 and we don't care about infinities. */
6117 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6120 /* sqrt(x) > c is the same as x > c*c. */
6121 return fold_build2_loc (loc, code, type, arg,
6122 build_real (TREE_TYPE (arg), c2));
6124 else if (code == LT_EXPR || code == LE_EXPR)
6128 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6129 real_convert (&c2, mode, &c2);
6131 if (REAL_VALUE_ISINF (c2))
6133 /* sqrt(x) < y is always true, when y is a very large
6134 value and we don't care about NaNs or Infinities. */
6135 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6136 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6138 /* sqrt(x) < y is x != +Inf when y is very large and we
6139 don't care about NaNs. */
6140 if (! HONOR_NANS (mode))
6141 return fold_build2_loc (loc, NE_EXPR, type, arg,
6142 build_real (TREE_TYPE (arg), c2));
6144 /* sqrt(x) < y is x >= 0 when y is very large and we
6145 don't care about Infinities. */
6146 if (! HONOR_INFINITIES (mode))
6147 return fold_build2_loc (loc, GE_EXPR, type, arg,
6148 build_real (TREE_TYPE (arg), dconst0));
6150 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6151 arg = save_expr (arg);
6152 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6153 fold_build2_loc (loc, GE_EXPR, type, arg,
6154 build_real (TREE_TYPE (arg),
6156 fold_build2_loc (loc, NE_EXPR, type, arg,
6157 build_real (TREE_TYPE (arg),
6161 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6162 if (! HONOR_NANS (mode))
6163 return fold_build2_loc (loc, code, type, arg,
6164 build_real (TREE_TYPE (arg), c2));
6166 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6167 arg = save_expr (arg);
6168 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6169 fold_build2_loc (loc, GE_EXPR, type, arg,
6170 build_real (TREE_TYPE (arg),
6172 fold_build2_loc (loc, code, type, arg,
6173 build_real (TREE_TYPE (arg),
6181 /* Subroutine of fold() that optimizes comparisons against Infinities,
6182 either +Inf or -Inf.
6184 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6185 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6186 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6188 The function returns the constant folded tree if a simplification
6189 can be made, and NULL_TREE otherwise. */
6192 fold_inf_compare (location_t loc, enum tree_code code, tree type,
6193 tree arg0, tree arg1)
6195 enum machine_mode mode;
6196 REAL_VALUE_TYPE max;
6200 mode = TYPE_MODE (TREE_TYPE (arg0));
6202 /* For negative infinity swap the sense of the comparison. */
6203 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6205 code = swap_tree_comparison (code);
6210 /* x > +Inf is always false, if with ignore sNANs. */
6211 if (HONOR_SNANS (mode))
6213 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6216 /* x <= +Inf is always true, if we don't case about NaNs. */
6217 if (! HONOR_NANS (mode))
6218 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6220 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6221 arg0 = save_expr (arg0);
6222 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg0);
6226 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6227 real_maxval (&max, neg, mode);
6228 return fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6229 arg0, build_real (TREE_TYPE (arg0), max));
6232 /* x < +Inf is always equal to x <= DBL_MAX. */
6233 real_maxval (&max, neg, mode);
6234 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6235 arg0, build_real (TREE_TYPE (arg0), max));
6238 /* x != +Inf is always equal to !(x > DBL_MAX). */
6239 real_maxval (&max, neg, mode);
6240 if (! HONOR_NANS (mode))
6241 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6242 arg0, build_real (TREE_TYPE (arg0), max));
6244 temp = fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6245 arg0, build_real (TREE_TYPE (arg0), max));
6246 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type, temp);
6255 /* Subroutine of fold() that optimizes comparisons of a division by
6256 a nonzero integer constant against an integer constant, i.e.
6259 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6260 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6261 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6263 The function returns the constant folded tree if a simplification
6264 can be made, and NULL_TREE otherwise. */
6267 fold_div_compare (location_t loc,
6268 enum tree_code code, tree type, tree arg0, tree arg1)
6270 tree prod, tmp, hi, lo;
6271 tree arg00 = TREE_OPERAND (arg0, 0);
6272 tree arg01 = TREE_OPERAND (arg0, 1);
6274 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6278 /* We have to do this the hard way to detect unsigned overflow.
6279 prod = int_const_binop (MULT_EXPR, arg01, arg1); */
6280 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6281 TREE_INT_CST_HIGH (arg01),
6282 TREE_INT_CST_LOW (arg1),
6283 TREE_INT_CST_HIGH (arg1),
6284 &val.low, &val.high, unsigned_p);
6285 prod = force_fit_type_double (TREE_TYPE (arg00), val, -1, overflow);
6286 neg_overflow = false;
6290 tmp = int_const_binop (MINUS_EXPR, arg01,
6291 build_int_cst (TREE_TYPE (arg01), 1));
6294 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp). */
6295 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6296 TREE_INT_CST_HIGH (prod),
6297 TREE_INT_CST_LOW (tmp),
6298 TREE_INT_CST_HIGH (tmp),
6299 &val.low, &val.high, unsigned_p);
6300 hi = force_fit_type_double (TREE_TYPE (arg00), val,
6301 -1, overflow | TREE_OVERFLOW (prod));
6303 else if (tree_int_cst_sgn (arg01) >= 0)
6305 tmp = int_const_binop (MINUS_EXPR, arg01,
6306 build_int_cst (TREE_TYPE (arg01), 1));
6307 switch (tree_int_cst_sgn (arg1))
6310 neg_overflow = true;
6311 lo = int_const_binop (MINUS_EXPR, prod, tmp);
6316 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6321 hi = int_const_binop (PLUS_EXPR, prod, tmp);
6331 /* A negative divisor reverses the relational operators. */
6332 code = swap_tree_comparison (code);
6334 tmp = int_const_binop (PLUS_EXPR, arg01,
6335 build_int_cst (TREE_TYPE (arg01), 1));
6336 switch (tree_int_cst_sgn (arg1))
6339 hi = int_const_binop (MINUS_EXPR, prod, tmp);
6344 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6349 neg_overflow = true;
6350 lo = int_const_binop (PLUS_EXPR, prod, tmp);
6362 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6363 return omit_one_operand_loc (loc, type, integer_zero_node, arg00);
6364 if (TREE_OVERFLOW (hi))
6365 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6366 if (TREE_OVERFLOW (lo))
6367 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6368 return build_range_check (loc, type, arg00, 1, lo, hi);
6371 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6372 return omit_one_operand_loc (loc, type, integer_one_node, arg00);
6373 if (TREE_OVERFLOW (hi))
6374 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6375 if (TREE_OVERFLOW (lo))
6376 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6377 return build_range_check (loc, type, arg00, 0, lo, hi);
6380 if (TREE_OVERFLOW (lo))
6382 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6383 return omit_one_operand_loc (loc, type, tmp, arg00);
6385 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6388 if (TREE_OVERFLOW (hi))
6390 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6391 return omit_one_operand_loc (loc, type, tmp, arg00);
6393 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6396 if (TREE_OVERFLOW (hi))
6398 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6399 return omit_one_operand_loc (loc, type, tmp, arg00);
6401 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6404 if (TREE_OVERFLOW (lo))
6406 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6407 return omit_one_operand_loc (loc, type, tmp, arg00);
6409 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6419 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6420 equality/inequality test, then return a simplified form of the test
6421 using a sign testing. Otherwise return NULL. TYPE is the desired
6425 fold_single_bit_test_into_sign_test (location_t loc,
6426 enum tree_code code, tree arg0, tree arg1,
6429 /* If this is testing a single bit, we can optimize the test. */
6430 if ((code == NE_EXPR || code == EQ_EXPR)
6431 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6432 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6434 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6435 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6436 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6438 if (arg00 != NULL_TREE
6439 /* This is only a win if casting to a signed type is cheap,
6440 i.e. when arg00's type is not a partial mode. */
6441 && TYPE_PRECISION (TREE_TYPE (arg00))
6442 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6444 tree stype = signed_type_for (TREE_TYPE (arg00));
6445 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6447 fold_convert_loc (loc, stype, arg00),
6448 build_int_cst (stype, 0));
6455 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6456 equality/inequality test, then return a simplified form of
6457 the test using shifts and logical operations. Otherwise return
6458 NULL. TYPE is the desired result type. */
6461 fold_single_bit_test (location_t loc, enum tree_code code,
6462 tree arg0, tree arg1, tree result_type)
6464 /* If this is testing a single bit, we can optimize the test. */
6465 if ((code == NE_EXPR || code == EQ_EXPR)
6466 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6467 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6469 tree inner = TREE_OPERAND (arg0, 0);
6470 tree type = TREE_TYPE (arg0);
6471 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6472 enum machine_mode operand_mode = TYPE_MODE (type);
6474 tree signed_type, unsigned_type, intermediate_type;
6477 /* First, see if we can fold the single bit test into a sign-bit
6479 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1,
6484 /* Otherwise we have (A & C) != 0 where C is a single bit,
6485 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6486 Similarly for (A & C) == 0. */
6488 /* If INNER is a right shift of a constant and it plus BITNUM does
6489 not overflow, adjust BITNUM and INNER. */
6490 if (TREE_CODE (inner) == RSHIFT_EXPR
6491 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6492 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6493 && bitnum < TYPE_PRECISION (type)
6494 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6495 bitnum - TYPE_PRECISION (type)))
6497 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6498 inner = TREE_OPERAND (inner, 0);
6501 /* If we are going to be able to omit the AND below, we must do our
6502 operations as unsigned. If we must use the AND, we have a choice.
6503 Normally unsigned is faster, but for some machines signed is. */
6504 #ifdef LOAD_EXTEND_OP
6505 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6506 && !flag_syntax_only) ? 0 : 1;
6511 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6512 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6513 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6514 inner = fold_convert_loc (loc, intermediate_type, inner);
6517 inner = build2 (RSHIFT_EXPR, intermediate_type,
6518 inner, size_int (bitnum));
6520 one = build_int_cst (intermediate_type, 1);
6522 if (code == EQ_EXPR)
6523 inner = fold_build2_loc (loc, BIT_XOR_EXPR, intermediate_type, inner, one);
6525 /* Put the AND last so it can combine with more things. */
6526 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6528 /* Make sure to return the proper type. */
6529 inner = fold_convert_loc (loc, result_type, inner);
6536 /* Check whether we are allowed to reorder operands arg0 and arg1,
6537 such that the evaluation of arg1 occurs before arg0. */
6540 reorder_operands_p (const_tree arg0, const_tree arg1)
6542 if (! flag_evaluation_order)
6544 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
6546 return ! TREE_SIDE_EFFECTS (arg0)
6547 && ! TREE_SIDE_EFFECTS (arg1);
6550 /* Test whether it is preferable two swap two operands, ARG0 and
6551 ARG1, for example because ARG0 is an integer constant and ARG1
6552 isn't. If REORDER is true, only recommend swapping if we can
6553 evaluate the operands in reverse order. */
6556 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
6558 STRIP_SIGN_NOPS (arg0);
6559 STRIP_SIGN_NOPS (arg1);
6561 if (TREE_CODE (arg1) == INTEGER_CST)
6563 if (TREE_CODE (arg0) == INTEGER_CST)
6566 if (TREE_CODE (arg1) == REAL_CST)
6568 if (TREE_CODE (arg0) == REAL_CST)
6571 if (TREE_CODE (arg1) == FIXED_CST)
6573 if (TREE_CODE (arg0) == FIXED_CST)
6576 if (TREE_CODE (arg1) == COMPLEX_CST)
6578 if (TREE_CODE (arg0) == COMPLEX_CST)
6581 if (TREE_CONSTANT (arg1))
6583 if (TREE_CONSTANT (arg0))
6586 if (optimize_function_for_size_p (cfun))
6589 if (reorder && flag_evaluation_order
6590 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
6593 /* It is preferable to swap two SSA_NAME to ensure a canonical form
6594 for commutative and comparison operators. Ensuring a canonical
6595 form allows the optimizers to find additional redundancies without
6596 having to explicitly check for both orderings. */
6597 if (TREE_CODE (arg0) == SSA_NAME
6598 && TREE_CODE (arg1) == SSA_NAME
6599 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
6602 /* Put SSA_NAMEs last. */
6603 if (TREE_CODE (arg1) == SSA_NAME)
6605 if (TREE_CODE (arg0) == SSA_NAME)
6608 /* Put variables last. */
6617 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
6618 ARG0 is extended to a wider type. */
6621 fold_widened_comparison (location_t loc, enum tree_code code,
6622 tree type, tree arg0, tree arg1)
6624 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
6626 tree shorter_type, outer_type;
6630 if (arg0_unw == arg0)
6632 shorter_type = TREE_TYPE (arg0_unw);
6634 #ifdef HAVE_canonicalize_funcptr_for_compare
6635 /* Disable this optimization if we're casting a function pointer
6636 type on targets that require function pointer canonicalization. */
6637 if (HAVE_canonicalize_funcptr_for_compare
6638 && TREE_CODE (shorter_type) == POINTER_TYPE
6639 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
6643 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
6646 arg1_unw = get_unwidened (arg1, NULL_TREE);
6648 /* If possible, express the comparison in the shorter mode. */
6649 if ((code == EQ_EXPR || code == NE_EXPR
6650 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
6651 && (TREE_TYPE (arg1_unw) == shorter_type
6652 || ((TYPE_PRECISION (shorter_type)
6653 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
6654 && (TYPE_UNSIGNED (shorter_type)
6655 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
6656 || (TREE_CODE (arg1_unw) == INTEGER_CST
6657 && (TREE_CODE (shorter_type) == INTEGER_TYPE
6658 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
6659 && int_fits_type_p (arg1_unw, shorter_type))))
6660 return fold_build2_loc (loc, code, type, arg0_unw,
6661 fold_convert_loc (loc, shorter_type, arg1_unw));
6663 if (TREE_CODE (arg1_unw) != INTEGER_CST
6664 || TREE_CODE (shorter_type) != INTEGER_TYPE
6665 || !int_fits_type_p (arg1_unw, shorter_type))
6668 /* If we are comparing with the integer that does not fit into the range
6669 of the shorter type, the result is known. */
6670 outer_type = TREE_TYPE (arg1_unw);
6671 min = lower_bound_in_type (outer_type, shorter_type);
6672 max = upper_bound_in_type (outer_type, shorter_type);
6674 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6676 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6683 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6688 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6694 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6696 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6701 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6703 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6712 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
6713 ARG0 just the signedness is changed. */
6716 fold_sign_changed_comparison (location_t loc, enum tree_code code, tree type,
6717 tree arg0, tree arg1)
6720 tree inner_type, outer_type;
6722 if (!CONVERT_EXPR_P (arg0))
6725 outer_type = TREE_TYPE (arg0);
6726 arg0_inner = TREE_OPERAND (arg0, 0);
6727 inner_type = TREE_TYPE (arg0_inner);
6729 #ifdef HAVE_canonicalize_funcptr_for_compare
6730 /* Disable this optimization if we're casting a function pointer
6731 type on targets that require function pointer canonicalization. */
6732 if (HAVE_canonicalize_funcptr_for_compare
6733 && TREE_CODE (inner_type) == POINTER_TYPE
6734 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
6738 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
6741 if (TREE_CODE (arg1) != INTEGER_CST
6742 && !(CONVERT_EXPR_P (arg1)
6743 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
6746 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
6747 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
6752 if (TREE_CODE (arg1) == INTEGER_CST)
6753 arg1 = force_fit_type_double (inner_type, tree_to_double_int (arg1),
6754 0, TREE_OVERFLOW (arg1));
6756 arg1 = fold_convert_loc (loc, inner_type, arg1);
6758 return fold_build2_loc (loc, code, type, arg0_inner, arg1);
6761 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
6762 step of the array. Reconstructs s and delta in the case of s *
6763 delta being an integer constant (and thus already folded). ADDR is
6764 the address. MULT is the multiplicative expression. If the
6765 function succeeds, the new address expression is returned.
6766 Otherwise NULL_TREE is returned. LOC is the location of the
6767 resulting expression. */
6770 try_move_mult_to_index (location_t loc, tree addr, tree op1)
6772 tree s, delta, step;
6773 tree ref = TREE_OPERAND (addr, 0), pref;
6778 /* Strip the nops that might be added when converting op1 to sizetype. */
6781 /* Canonicalize op1 into a possibly non-constant delta
6782 and an INTEGER_CST s. */
6783 if (TREE_CODE (op1) == MULT_EXPR)
6785 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
6790 if (TREE_CODE (arg0) == INTEGER_CST)
6795 else if (TREE_CODE (arg1) == INTEGER_CST)
6803 else if (TREE_CODE (op1) == INTEGER_CST)
6810 /* Simulate we are delta * 1. */
6812 s = integer_one_node;
6815 for (;; ref = TREE_OPERAND (ref, 0))
6817 if (TREE_CODE (ref) == ARRAY_REF)
6821 /* Remember if this was a multi-dimensional array. */
6822 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
6825 domain = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
6828 itype = TREE_TYPE (domain);
6830 step = array_ref_element_size (ref);
6831 if (TREE_CODE (step) != INTEGER_CST)
6836 if (! tree_int_cst_equal (step, s))
6841 /* Try if delta is a multiple of step. */
6842 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
6848 /* Only fold here if we can verify we do not overflow one
6849 dimension of a multi-dimensional array. */
6854 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
6855 || !TYPE_MAX_VALUE (domain)
6856 || TREE_CODE (TYPE_MAX_VALUE (domain)) != INTEGER_CST)
6859 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
6860 fold_convert_loc (loc, itype,
6861 TREE_OPERAND (ref, 1)),
6862 fold_convert_loc (loc, itype, delta));
6864 || TREE_CODE (tmp) != INTEGER_CST
6865 || tree_int_cst_lt (TYPE_MAX_VALUE (domain), tmp))
6874 if (!handled_component_p (ref))
6878 /* We found the suitable array reference. So copy everything up to it,
6879 and replace the index. */
6881 pref = TREE_OPERAND (addr, 0);
6882 ret = copy_node (pref);
6883 SET_EXPR_LOCATION (ret, loc);
6888 pref = TREE_OPERAND (pref, 0);
6889 TREE_OPERAND (pos, 0) = copy_node (pref);
6890 pos = TREE_OPERAND (pos, 0);
6893 TREE_OPERAND (pos, 1) = fold_build2_loc (loc, PLUS_EXPR, itype,
6894 fold_convert_loc (loc, itype,
6895 TREE_OPERAND (pos, 1)),
6896 fold_convert_loc (loc, itype, delta));
6898 return fold_build1_loc (loc, ADDR_EXPR, TREE_TYPE (addr), ret);
6902 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
6903 means A >= Y && A != MAX, but in this case we know that
6904 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
6907 fold_to_nonsharp_ineq_using_bound (location_t loc, tree ineq, tree bound)
6909 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
6911 if (TREE_CODE (bound) == LT_EXPR)
6912 a = TREE_OPERAND (bound, 0);
6913 else if (TREE_CODE (bound) == GT_EXPR)
6914 a = TREE_OPERAND (bound, 1);
6918 typea = TREE_TYPE (a);
6919 if (!INTEGRAL_TYPE_P (typea)
6920 && !POINTER_TYPE_P (typea))
6923 if (TREE_CODE (ineq) == LT_EXPR)
6925 a1 = TREE_OPERAND (ineq, 1);
6926 y = TREE_OPERAND (ineq, 0);
6928 else if (TREE_CODE (ineq) == GT_EXPR)
6930 a1 = TREE_OPERAND (ineq, 0);
6931 y = TREE_OPERAND (ineq, 1);
6936 if (TREE_TYPE (a1) != typea)
6939 if (POINTER_TYPE_P (typea))
6941 /* Convert the pointer types into integer before taking the difference. */
6942 tree ta = fold_convert_loc (loc, ssizetype, a);
6943 tree ta1 = fold_convert_loc (loc, ssizetype, a1);
6944 diff = fold_binary_loc (loc, MINUS_EXPR, ssizetype, ta1, ta);
6947 diff = fold_binary_loc (loc, MINUS_EXPR, typea, a1, a);
6949 if (!diff || !integer_onep (diff))
6952 return fold_build2_loc (loc, GE_EXPR, type, a, y);
6955 /* Fold a sum or difference of at least one multiplication.
6956 Returns the folded tree or NULL if no simplification could be made. */
6959 fold_plusminus_mult_expr (location_t loc, enum tree_code code, tree type,
6960 tree arg0, tree arg1)
6962 tree arg00, arg01, arg10, arg11;
6963 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
6965 /* (A * C) +- (B * C) -> (A+-B) * C.
6966 (A * C) +- A -> A * (C+-1).
6967 We are most concerned about the case where C is a constant,
6968 but other combinations show up during loop reduction. Since
6969 it is not difficult, try all four possibilities. */
6971 if (TREE_CODE (arg0) == MULT_EXPR)
6973 arg00 = TREE_OPERAND (arg0, 0);
6974 arg01 = TREE_OPERAND (arg0, 1);
6976 else if (TREE_CODE (arg0) == INTEGER_CST)
6978 arg00 = build_one_cst (type);
6983 /* We cannot generate constant 1 for fract. */
6984 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
6987 arg01 = build_one_cst (type);
6989 if (TREE_CODE (arg1) == MULT_EXPR)
6991 arg10 = TREE_OPERAND (arg1, 0);
6992 arg11 = TREE_OPERAND (arg1, 1);
6994 else if (TREE_CODE (arg1) == INTEGER_CST)
6996 arg10 = build_one_cst (type);
6997 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
6998 the purpose of this canonicalization. */
6999 if (TREE_INT_CST_HIGH (arg1) == -1
7000 && negate_expr_p (arg1)
7001 && code == PLUS_EXPR)
7003 arg11 = negate_expr (arg1);
7011 /* We cannot generate constant 1 for fract. */
7012 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7015 arg11 = build_one_cst (type);
7019 if (operand_equal_p (arg01, arg11, 0))
7020 same = arg01, alt0 = arg00, alt1 = arg10;
7021 else if (operand_equal_p (arg00, arg10, 0))
7022 same = arg00, alt0 = arg01, alt1 = arg11;
7023 else if (operand_equal_p (arg00, arg11, 0))
7024 same = arg00, alt0 = arg01, alt1 = arg10;
7025 else if (operand_equal_p (arg01, arg10, 0))
7026 same = arg01, alt0 = arg00, alt1 = arg11;
7028 /* No identical multiplicands; see if we can find a common
7029 power-of-two factor in non-power-of-two multiplies. This
7030 can help in multi-dimensional array access. */
7031 else if (host_integerp (arg01, 0)
7032 && host_integerp (arg11, 0))
7034 HOST_WIDE_INT int01, int11, tmp;
7037 int01 = TREE_INT_CST_LOW (arg01);
7038 int11 = TREE_INT_CST_LOW (arg11);
7040 /* Move min of absolute values to int11. */
7041 if ((int01 >= 0 ? int01 : -int01)
7042 < (int11 >= 0 ? int11 : -int11))
7044 tmp = int01, int01 = int11, int11 = tmp;
7045 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7052 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
7053 /* The remainder should not be a constant, otherwise we
7054 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7055 increased the number of multiplications necessary. */
7056 && TREE_CODE (arg10) != INTEGER_CST)
7058 alt0 = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (arg00), arg00,
7059 build_int_cst (TREE_TYPE (arg00),
7064 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7069 return fold_build2_loc (loc, MULT_EXPR, type,
7070 fold_build2_loc (loc, code, type,
7071 fold_convert_loc (loc, type, alt0),
7072 fold_convert_loc (loc, type, alt1)),
7073 fold_convert_loc (loc, type, same));
7078 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7079 specified by EXPR into the buffer PTR of length LEN bytes.
7080 Return the number of bytes placed in the buffer, or zero
7084 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7086 tree type = TREE_TYPE (expr);
7087 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7088 int byte, offset, word, words;
7089 unsigned char value;
7091 if (total_bytes > len)
7093 words = total_bytes / UNITS_PER_WORD;
7095 for (byte = 0; byte < total_bytes; byte++)
7097 int bitpos = byte * BITS_PER_UNIT;
7098 if (bitpos < HOST_BITS_PER_WIDE_INT)
7099 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7101 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7102 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7104 if (total_bytes > UNITS_PER_WORD)
7106 word = byte / UNITS_PER_WORD;
7107 if (WORDS_BIG_ENDIAN)
7108 word = (words - 1) - word;
7109 offset = word * UNITS_PER_WORD;
7110 if (BYTES_BIG_ENDIAN)
7111 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7113 offset += byte % UNITS_PER_WORD;
7116 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7117 ptr[offset] = value;
7123 /* Subroutine of native_encode_expr. Encode the REAL_CST
7124 specified by EXPR into the buffer PTR of length LEN bytes.
7125 Return the number of bytes placed in the buffer, or zero
7129 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7131 tree type = TREE_TYPE (expr);
7132 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7133 int byte, offset, word, words, bitpos;
7134 unsigned char value;
7136 /* There are always 32 bits in each long, no matter the size of
7137 the hosts long. We handle floating point representations with
7141 if (total_bytes > len)
7143 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7145 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7147 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7148 bitpos += BITS_PER_UNIT)
7150 byte = (bitpos / BITS_PER_UNIT) & 3;
7151 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7153 if (UNITS_PER_WORD < 4)
7155 word = byte / UNITS_PER_WORD;
7156 if (WORDS_BIG_ENDIAN)
7157 word = (words - 1) - word;
7158 offset = word * UNITS_PER_WORD;
7159 if (BYTES_BIG_ENDIAN)
7160 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7162 offset += byte % UNITS_PER_WORD;
7165 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7166 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7171 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7172 specified by EXPR into the buffer PTR of length LEN bytes.
7173 Return the number of bytes placed in the buffer, or zero
7177 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7182 part = TREE_REALPART (expr);
7183 rsize = native_encode_expr (part, ptr, len);
7186 part = TREE_IMAGPART (expr);
7187 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7190 return rsize + isize;
7194 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7195 specified by EXPR into the buffer PTR of length LEN bytes.
7196 Return the number of bytes placed in the buffer, or zero
7200 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7202 int i, size, offset, count;
7203 tree itype, elem, elements;
7206 elements = TREE_VECTOR_CST_ELTS (expr);
7207 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7208 itype = TREE_TYPE (TREE_TYPE (expr));
7209 size = GET_MODE_SIZE (TYPE_MODE (itype));
7210 for (i = 0; i < count; i++)
7214 elem = TREE_VALUE (elements);
7215 elements = TREE_CHAIN (elements);
7222 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7227 if (offset + size > len)
7229 memset (ptr+offset, 0, size);
7237 /* Subroutine of native_encode_expr. Encode the STRING_CST
7238 specified by EXPR into the buffer PTR of length LEN bytes.
7239 Return the number of bytes placed in the buffer, or zero
7243 native_encode_string (const_tree expr, unsigned char *ptr, int len)
7245 tree type = TREE_TYPE (expr);
7246 HOST_WIDE_INT total_bytes;
7248 if (TREE_CODE (type) != ARRAY_TYPE
7249 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
7250 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
7251 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
7253 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
7254 if (total_bytes > len)
7256 if (TREE_STRING_LENGTH (expr) < total_bytes)
7258 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
7259 memset (ptr + TREE_STRING_LENGTH (expr), 0,
7260 total_bytes - TREE_STRING_LENGTH (expr));
7263 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
7268 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7269 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7270 buffer PTR of length LEN bytes. Return the number of bytes
7271 placed in the buffer, or zero upon failure. */
7274 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7276 switch (TREE_CODE (expr))
7279 return native_encode_int (expr, ptr, len);
7282 return native_encode_real (expr, ptr, len);
7285 return native_encode_complex (expr, ptr, len);
7288 return native_encode_vector (expr, ptr, len);
7291 return native_encode_string (expr, ptr, len);
7299 /* Subroutine of native_interpret_expr. Interpret the contents of
7300 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7301 If the buffer cannot be interpreted, return NULL_TREE. */
7304 native_interpret_int (tree type, const unsigned char *ptr, int len)
7306 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7307 int byte, offset, word, words;
7308 unsigned char value;
7311 if (total_bytes > len)
7313 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7316 result = double_int_zero;
7317 words = total_bytes / UNITS_PER_WORD;
7319 for (byte = 0; byte < total_bytes; byte++)
7321 int bitpos = byte * BITS_PER_UNIT;
7322 if (total_bytes > UNITS_PER_WORD)
7324 word = byte / UNITS_PER_WORD;
7325 if (WORDS_BIG_ENDIAN)
7326 word = (words - 1) - word;
7327 offset = word * UNITS_PER_WORD;
7328 if (BYTES_BIG_ENDIAN)
7329 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7331 offset += byte % UNITS_PER_WORD;
7334 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7335 value = ptr[offset];
7337 if (bitpos < HOST_BITS_PER_WIDE_INT)
7338 result.low |= (unsigned HOST_WIDE_INT) value << bitpos;
7340 result.high |= (unsigned HOST_WIDE_INT) value
7341 << (bitpos - HOST_BITS_PER_WIDE_INT);
7344 return double_int_to_tree (type, result);
7348 /* Subroutine of native_interpret_expr. Interpret the contents of
7349 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7350 If the buffer cannot be interpreted, return NULL_TREE. */
7353 native_interpret_real (tree type, const unsigned char *ptr, int len)
7355 enum machine_mode mode = TYPE_MODE (type);
7356 int total_bytes = GET_MODE_SIZE (mode);
7357 int byte, offset, word, words, bitpos;
7358 unsigned char value;
7359 /* There are always 32 bits in each long, no matter the size of
7360 the hosts long. We handle floating point representations with
7365 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7366 if (total_bytes > len || total_bytes > 24)
7368 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7370 memset (tmp, 0, sizeof (tmp));
7371 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7372 bitpos += BITS_PER_UNIT)
7374 byte = (bitpos / BITS_PER_UNIT) & 3;
7375 if (UNITS_PER_WORD < 4)
7377 word = byte / UNITS_PER_WORD;
7378 if (WORDS_BIG_ENDIAN)
7379 word = (words - 1) - word;
7380 offset = word * UNITS_PER_WORD;
7381 if (BYTES_BIG_ENDIAN)
7382 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7384 offset += byte % UNITS_PER_WORD;
7387 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7388 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7390 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7393 real_from_target (&r, tmp, mode);
7394 return build_real (type, r);
7398 /* Subroutine of native_interpret_expr. Interpret the contents of
7399 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7400 If the buffer cannot be interpreted, return NULL_TREE. */
7403 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7405 tree etype, rpart, ipart;
7408 etype = TREE_TYPE (type);
7409 size = GET_MODE_SIZE (TYPE_MODE (etype));
7412 rpart = native_interpret_expr (etype, ptr, size);
7415 ipart = native_interpret_expr (etype, ptr+size, size);
7418 return build_complex (type, rpart, ipart);
7422 /* Subroutine of native_interpret_expr. Interpret the contents of
7423 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7424 If the buffer cannot be interpreted, return NULL_TREE. */
7427 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7429 tree etype, elem, elements;
7432 etype = TREE_TYPE (type);
7433 size = GET_MODE_SIZE (TYPE_MODE (etype));
7434 count = TYPE_VECTOR_SUBPARTS (type);
7435 if (size * count > len)
7438 elements = NULL_TREE;
7439 for (i = count - 1; i >= 0; i--)
7441 elem = native_interpret_expr (etype, ptr+(i*size), size);
7444 elements = tree_cons (NULL_TREE, elem, elements);
7446 return build_vector (type, elements);
7450 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7451 the buffer PTR of length LEN as a constant of type TYPE. For
7452 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7453 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7454 return NULL_TREE. */
7457 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7459 switch (TREE_CODE (type))
7464 return native_interpret_int (type, ptr, len);
7467 return native_interpret_real (type, ptr, len);
7470 return native_interpret_complex (type, ptr, len);
7473 return native_interpret_vector (type, ptr, len);
7481 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7482 TYPE at compile-time. If we're unable to perform the conversion
7483 return NULL_TREE. */
7486 fold_view_convert_expr (tree type, tree expr)
7488 /* We support up to 512-bit values (for V8DFmode). */
7489 unsigned char buffer[64];
7492 /* Check that the host and target are sane. */
7493 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7496 len = native_encode_expr (expr, buffer, sizeof (buffer));
7500 return native_interpret_expr (type, buffer, len);
7503 /* Build an expression for the address of T. Folds away INDIRECT_REF
7504 to avoid confusing the gimplify process. */
7507 build_fold_addr_expr_with_type_loc (location_t loc, tree t, tree ptrtype)
7509 /* The size of the object is not relevant when talking about its address. */
7510 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7511 t = TREE_OPERAND (t, 0);
7513 if (TREE_CODE (t) == INDIRECT_REF)
7515 t = TREE_OPERAND (t, 0);
7517 if (TREE_TYPE (t) != ptrtype)
7518 t = build1_loc (loc, NOP_EXPR, ptrtype, t);
7520 else if (TREE_CODE (t) == MEM_REF
7521 && integer_zerop (TREE_OPERAND (t, 1)))
7522 return TREE_OPERAND (t, 0);
7523 else if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
7525 t = build_fold_addr_expr_loc (loc, TREE_OPERAND (t, 0));
7527 if (TREE_TYPE (t) != ptrtype)
7528 t = fold_convert_loc (loc, ptrtype, t);
7531 t = build1_loc (loc, ADDR_EXPR, ptrtype, t);
7536 /* Build an expression for the address of T. */
7539 build_fold_addr_expr_loc (location_t loc, tree t)
7541 tree ptrtype = build_pointer_type (TREE_TYPE (t));
7543 return build_fold_addr_expr_with_type_loc (loc, t, ptrtype);
7546 /* Fold a unary expression of code CODE and type TYPE with operand
7547 OP0. Return the folded expression if folding is successful.
7548 Otherwise, return NULL_TREE. */
7551 fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
7555 enum tree_code_class kind = TREE_CODE_CLASS (code);
7557 gcc_assert (IS_EXPR_CODE_CLASS (kind)
7558 && TREE_CODE_LENGTH (code) == 1);
7563 if (CONVERT_EXPR_CODE_P (code)
7564 || code == FLOAT_EXPR || code == ABS_EXPR || code == NEGATE_EXPR)
7566 /* Don't use STRIP_NOPS, because signedness of argument type
7568 STRIP_SIGN_NOPS (arg0);
7572 /* Strip any conversions that don't change the mode. This
7573 is safe for every expression, except for a comparison
7574 expression because its signedness is derived from its
7577 Note that this is done as an internal manipulation within
7578 the constant folder, in order to find the simplest
7579 representation of the arguments so that their form can be
7580 studied. In any cases, the appropriate type conversions
7581 should be put back in the tree that will get out of the
7587 if (TREE_CODE_CLASS (code) == tcc_unary)
7589 if (TREE_CODE (arg0) == COMPOUND_EXPR)
7590 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
7591 fold_build1_loc (loc, code, type,
7592 fold_convert_loc (loc, TREE_TYPE (op0),
7593 TREE_OPERAND (arg0, 1))));
7594 else if (TREE_CODE (arg0) == COND_EXPR)
7596 tree arg01 = TREE_OPERAND (arg0, 1);
7597 tree arg02 = TREE_OPERAND (arg0, 2);
7598 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
7599 arg01 = fold_build1_loc (loc, code, type,
7600 fold_convert_loc (loc,
7601 TREE_TYPE (op0), arg01));
7602 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
7603 arg02 = fold_build1_loc (loc, code, type,
7604 fold_convert_loc (loc,
7605 TREE_TYPE (op0), arg02));
7606 tem = fold_build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg0, 0),
7609 /* If this was a conversion, and all we did was to move into
7610 inside the COND_EXPR, bring it back out. But leave it if
7611 it is a conversion from integer to integer and the
7612 result precision is no wider than a word since such a
7613 conversion is cheap and may be optimized away by combine,
7614 while it couldn't if it were outside the COND_EXPR. Then return
7615 so we don't get into an infinite recursion loop taking the
7616 conversion out and then back in. */
7618 if ((CONVERT_EXPR_CODE_P (code)
7619 || code == NON_LVALUE_EXPR)
7620 && TREE_CODE (tem) == COND_EXPR
7621 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
7622 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
7623 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
7624 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
7625 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
7626 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
7627 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7629 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
7630 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
7631 || flag_syntax_only))
7632 tem = build1_loc (loc, code, type,
7634 TREE_TYPE (TREE_OPERAND
7635 (TREE_OPERAND (tem, 1), 0)),
7636 TREE_OPERAND (tem, 0),
7637 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
7638 TREE_OPERAND (TREE_OPERAND (tem, 2),
7647 /* Re-association barriers around constants and other re-association
7648 barriers can be removed. */
7649 if (CONSTANT_CLASS_P (op0)
7650 || TREE_CODE (op0) == PAREN_EXPR)
7651 return fold_convert_loc (loc, type, op0);
7656 case FIX_TRUNC_EXPR:
7657 if (TREE_TYPE (op0) == type)
7660 if (COMPARISON_CLASS_P (op0))
7662 /* If we have (type) (a CMP b) and type is an integral type, return
7663 new expression involving the new type. Canonicalize
7664 (type) (a CMP b) to (a CMP b) ? (type) true : (type) false for
7666 Do not fold the result as that would not simplify further, also
7667 folding again results in recursions. */
7668 if (INTEGRAL_TYPE_P (type))
7669 return build2_loc (loc, TREE_CODE (op0), type,
7670 TREE_OPERAND (op0, 0),
7671 TREE_OPERAND (op0, 1));
7673 return build3_loc (loc, COND_EXPR, type, op0,
7674 fold_convert (type, boolean_true_node),
7675 fold_convert (type, boolean_false_node));
7678 /* Handle cases of two conversions in a row. */
7679 if (CONVERT_EXPR_P (op0))
7681 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
7682 tree inter_type = TREE_TYPE (op0);
7683 int inside_int = INTEGRAL_TYPE_P (inside_type);
7684 int inside_ptr = POINTER_TYPE_P (inside_type);
7685 int inside_float = FLOAT_TYPE_P (inside_type);
7686 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
7687 unsigned int inside_prec = TYPE_PRECISION (inside_type);
7688 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
7689 int inter_int = INTEGRAL_TYPE_P (inter_type);
7690 int inter_ptr = POINTER_TYPE_P (inter_type);
7691 int inter_float = FLOAT_TYPE_P (inter_type);
7692 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
7693 unsigned int inter_prec = TYPE_PRECISION (inter_type);
7694 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
7695 int final_int = INTEGRAL_TYPE_P (type);
7696 int final_ptr = POINTER_TYPE_P (type);
7697 int final_float = FLOAT_TYPE_P (type);
7698 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
7699 unsigned int final_prec = TYPE_PRECISION (type);
7700 int final_unsignedp = TYPE_UNSIGNED (type);
7702 /* In addition to the cases of two conversions in a row
7703 handled below, if we are converting something to its own
7704 type via an object of identical or wider precision, neither
7705 conversion is needed. */
7706 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
7707 && (((inter_int || inter_ptr) && final_int)
7708 || (inter_float && final_float))
7709 && inter_prec >= final_prec)
7710 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7712 /* Likewise, if the intermediate and initial types are either both
7713 float or both integer, we don't need the middle conversion if the
7714 former is wider than the latter and doesn't change the signedness
7715 (for integers). Avoid this if the final type is a pointer since
7716 then we sometimes need the middle conversion. Likewise if the
7717 final type has a precision not equal to the size of its mode. */
7718 if (((inter_int && inside_int)
7719 || (inter_float && inside_float)
7720 || (inter_vec && inside_vec))
7721 && inter_prec >= inside_prec
7722 && (inter_float || inter_vec
7723 || inter_unsignedp == inside_unsignedp)
7724 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7725 && TYPE_MODE (type) == TYPE_MODE (inter_type))
7727 && (! final_vec || inter_prec == inside_prec))
7728 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7730 /* If we have a sign-extension of a zero-extended value, we can
7731 replace that by a single zero-extension. */
7732 if (inside_int && inter_int && final_int
7733 && inside_prec < inter_prec && inter_prec < final_prec
7734 && inside_unsignedp && !inter_unsignedp)
7735 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7737 /* Two conversions in a row are not needed unless:
7738 - some conversion is floating-point (overstrict for now), or
7739 - some conversion is a vector (overstrict for now), or
7740 - the intermediate type is narrower than both initial and
7742 - the intermediate type and innermost type differ in signedness,
7743 and the outermost type is wider than the intermediate, or
7744 - the initial type is a pointer type and the precisions of the
7745 intermediate and final types differ, or
7746 - the final type is a pointer type and the precisions of the
7747 initial and intermediate types differ. */
7748 if (! inside_float && ! inter_float && ! final_float
7749 && ! inside_vec && ! inter_vec && ! final_vec
7750 && (inter_prec >= inside_prec || inter_prec >= final_prec)
7751 && ! (inside_int && inter_int
7752 && inter_unsignedp != inside_unsignedp
7753 && inter_prec < final_prec)
7754 && ((inter_unsignedp && inter_prec > inside_prec)
7755 == (final_unsignedp && final_prec > inter_prec))
7756 && ! (inside_ptr && inter_prec != final_prec)
7757 && ! (final_ptr && inside_prec != inter_prec)
7758 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7759 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
7760 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7763 /* Handle (T *)&A.B.C for A being of type T and B and C
7764 living at offset zero. This occurs frequently in
7765 C++ upcasting and then accessing the base. */
7766 if (TREE_CODE (op0) == ADDR_EXPR
7767 && POINTER_TYPE_P (type)
7768 && handled_component_p (TREE_OPERAND (op0, 0)))
7770 HOST_WIDE_INT bitsize, bitpos;
7772 enum machine_mode mode;
7773 int unsignedp, volatilep;
7774 tree base = TREE_OPERAND (op0, 0);
7775 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
7776 &mode, &unsignedp, &volatilep, false);
7777 /* If the reference was to a (constant) zero offset, we can use
7778 the address of the base if it has the same base type
7779 as the result type and the pointer type is unqualified. */
7780 if (! offset && bitpos == 0
7781 && (TYPE_MAIN_VARIANT (TREE_TYPE (type))
7782 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
7783 && TYPE_QUALS (type) == TYPE_UNQUALIFIED)
7784 return fold_convert_loc (loc, type,
7785 build_fold_addr_expr_loc (loc, base));
7788 if (TREE_CODE (op0) == MODIFY_EXPR
7789 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
7790 /* Detect assigning a bitfield. */
7791 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
7793 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
7795 /* Don't leave an assignment inside a conversion
7796 unless assigning a bitfield. */
7797 tem = fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 1));
7798 /* First do the assignment, then return converted constant. */
7799 tem = build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
7800 TREE_NO_WARNING (tem) = 1;
7801 TREE_USED (tem) = 1;
7805 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
7806 constants (if x has signed type, the sign bit cannot be set
7807 in c). This folds extension into the BIT_AND_EXPR.
7808 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
7809 very likely don't have maximal range for their precision and this
7810 transformation effectively doesn't preserve non-maximal ranges. */
7811 if (TREE_CODE (type) == INTEGER_TYPE
7812 && TREE_CODE (op0) == BIT_AND_EXPR
7813 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
7815 tree and_expr = op0;
7816 tree and0 = TREE_OPERAND (and_expr, 0);
7817 tree and1 = TREE_OPERAND (and_expr, 1);
7820 if (TYPE_UNSIGNED (TREE_TYPE (and_expr))
7821 || (TYPE_PRECISION (type)
7822 <= TYPE_PRECISION (TREE_TYPE (and_expr))))
7824 else if (TYPE_PRECISION (TREE_TYPE (and1))
7825 <= HOST_BITS_PER_WIDE_INT
7826 && host_integerp (and1, 1))
7828 unsigned HOST_WIDE_INT cst;
7830 cst = tree_low_cst (and1, 1);
7831 cst &= (HOST_WIDE_INT) -1
7832 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
7833 change = (cst == 0);
7834 #ifdef LOAD_EXTEND_OP
7836 && !flag_syntax_only
7837 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
7840 tree uns = unsigned_type_for (TREE_TYPE (and0));
7841 and0 = fold_convert_loc (loc, uns, and0);
7842 and1 = fold_convert_loc (loc, uns, and1);
7848 tem = force_fit_type_double (type, tree_to_double_int (and1),
7849 0, TREE_OVERFLOW (and1));
7850 return fold_build2_loc (loc, BIT_AND_EXPR, type,
7851 fold_convert_loc (loc, type, and0), tem);
7855 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
7856 when one of the new casts will fold away. Conservatively we assume
7857 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
7858 if (POINTER_TYPE_P (type)
7859 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
7860 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
7861 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
7862 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
7864 tree arg00 = TREE_OPERAND (arg0, 0);
7865 tree arg01 = TREE_OPERAND (arg0, 1);
7867 return fold_build2_loc (loc,
7868 TREE_CODE (arg0), type,
7869 fold_convert_loc (loc, type, arg00),
7870 fold_convert_loc (loc, sizetype, arg01));
7873 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
7874 of the same precision, and X is an integer type not narrower than
7875 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
7876 if (INTEGRAL_TYPE_P (type)
7877 && TREE_CODE (op0) == BIT_NOT_EXPR
7878 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7879 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
7880 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
7882 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
7883 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7884 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
7885 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
7886 fold_convert_loc (loc, type, tem));
7889 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
7890 type of X and Y (integer types only). */
7891 if (INTEGRAL_TYPE_P (type)
7892 && TREE_CODE (op0) == MULT_EXPR
7893 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7894 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
7896 /* Be careful not to introduce new overflows. */
7898 if (TYPE_OVERFLOW_WRAPS (type))
7901 mult_type = unsigned_type_for (type);
7903 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
7905 tem = fold_build2_loc (loc, MULT_EXPR, mult_type,
7906 fold_convert_loc (loc, mult_type,
7907 TREE_OPERAND (op0, 0)),
7908 fold_convert_loc (loc, mult_type,
7909 TREE_OPERAND (op0, 1)));
7910 return fold_convert_loc (loc, type, tem);
7914 tem = fold_convert_const (code, type, op0);
7915 return tem ? tem : NULL_TREE;
7917 case ADDR_SPACE_CONVERT_EXPR:
7918 if (integer_zerop (arg0))
7919 return fold_convert_const (code, type, arg0);
7922 case FIXED_CONVERT_EXPR:
7923 tem = fold_convert_const (code, type, arg0);
7924 return tem ? tem : NULL_TREE;
7926 case VIEW_CONVERT_EXPR:
7927 if (TREE_TYPE (op0) == type)
7929 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
7930 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
7931 type, TREE_OPERAND (op0, 0));
7932 if (TREE_CODE (op0) == MEM_REF)
7933 return fold_build2_loc (loc, MEM_REF, type,
7934 TREE_OPERAND (op0, 0), TREE_OPERAND (op0, 1));
7936 /* For integral conversions with the same precision or pointer
7937 conversions use a NOP_EXPR instead. */
7938 if ((INTEGRAL_TYPE_P (type)
7939 || POINTER_TYPE_P (type))
7940 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
7941 || POINTER_TYPE_P (TREE_TYPE (op0)))
7942 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
7943 return fold_convert_loc (loc, type, op0);
7945 /* Strip inner integral conversions that do not change the precision. */
7946 if (CONVERT_EXPR_P (op0)
7947 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
7948 || POINTER_TYPE_P (TREE_TYPE (op0)))
7949 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
7950 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
7951 && (TYPE_PRECISION (TREE_TYPE (op0))
7952 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
7953 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
7954 type, TREE_OPERAND (op0, 0));
7956 return fold_view_convert_expr (type, op0);
7959 tem = fold_negate_expr (loc, arg0);
7961 return fold_convert_loc (loc, type, tem);
7965 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
7966 return fold_abs_const (arg0, type);
7967 else if (TREE_CODE (arg0) == NEGATE_EXPR)
7968 return fold_build1_loc (loc, ABS_EXPR, type, TREE_OPERAND (arg0, 0));
7969 /* Convert fabs((double)float) into (double)fabsf(float). */
7970 else if (TREE_CODE (arg0) == NOP_EXPR
7971 && TREE_CODE (type) == REAL_TYPE)
7973 tree targ0 = strip_float_extensions (arg0);
7975 return fold_convert_loc (loc, type,
7976 fold_build1_loc (loc, ABS_EXPR,
7980 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
7981 else if (TREE_CODE (arg0) == ABS_EXPR)
7983 else if (tree_expr_nonnegative_p (arg0))
7986 /* Strip sign ops from argument. */
7987 if (TREE_CODE (type) == REAL_TYPE)
7989 tem = fold_strip_sign_ops (arg0);
7991 return fold_build1_loc (loc, ABS_EXPR, type,
7992 fold_convert_loc (loc, type, tem));
7997 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
7998 return fold_convert_loc (loc, type, arg0);
7999 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8001 tree itype = TREE_TYPE (type);
8002 tree rpart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 0));
8003 tree ipart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 1));
8004 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart,
8005 negate_expr (ipart));
8007 if (TREE_CODE (arg0) == COMPLEX_CST)
8009 tree itype = TREE_TYPE (type);
8010 tree rpart = fold_convert_loc (loc, itype, TREE_REALPART (arg0));
8011 tree ipart = fold_convert_loc (loc, itype, TREE_IMAGPART (arg0));
8012 return build_complex (type, rpart, negate_expr (ipart));
8014 if (TREE_CODE (arg0) == CONJ_EXPR)
8015 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8019 if (TREE_CODE (arg0) == INTEGER_CST)
8020 return fold_not_const (arg0, type);
8021 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8022 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8023 /* Convert ~ (-A) to A - 1. */
8024 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8025 return fold_build2_loc (loc, MINUS_EXPR, type,
8026 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)),
8027 build_int_cst (type, 1));
8028 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8029 else if (INTEGRAL_TYPE_P (type)
8030 && ((TREE_CODE (arg0) == MINUS_EXPR
8031 && integer_onep (TREE_OPERAND (arg0, 1)))
8032 || (TREE_CODE (arg0) == PLUS_EXPR
8033 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8034 return fold_build1_loc (loc, NEGATE_EXPR, type,
8035 fold_convert_loc (loc, type,
8036 TREE_OPERAND (arg0, 0)));
8037 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8038 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8039 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8040 fold_convert_loc (loc, type,
8041 TREE_OPERAND (arg0, 0)))))
8042 return fold_build2_loc (loc, BIT_XOR_EXPR, type, tem,
8043 fold_convert_loc (loc, type,
8044 TREE_OPERAND (arg0, 1)));
8045 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8046 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8047 fold_convert_loc (loc, type,
8048 TREE_OPERAND (arg0, 1)))))
8049 return fold_build2_loc (loc, BIT_XOR_EXPR, type,
8050 fold_convert_loc (loc, type,
8051 TREE_OPERAND (arg0, 0)), tem);
8052 /* Perform BIT_NOT_EXPR on each element individually. */
8053 else if (TREE_CODE (arg0) == VECTOR_CST)
8055 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8056 int count = TYPE_VECTOR_SUBPARTS (type), i;
8058 for (i = 0; i < count; i++)
8062 elem = TREE_VALUE (elements);
8063 elem = fold_unary_loc (loc, BIT_NOT_EXPR, TREE_TYPE (type), elem);
8064 if (elem == NULL_TREE)
8066 elements = TREE_CHAIN (elements);
8069 elem = build_int_cst (TREE_TYPE (type), -1);
8070 list = tree_cons (NULL_TREE, elem, list);
8073 return build_vector (type, nreverse (list));
8078 case TRUTH_NOT_EXPR:
8079 /* The argument to invert_truthvalue must have Boolean type. */
8080 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8081 arg0 = fold_convert_loc (loc, boolean_type_node, arg0);
8083 /* Note that the operand of this must be an int
8084 and its values must be 0 or 1.
8085 ("true" is a fixed value perhaps depending on the language,
8086 but we don't handle values other than 1 correctly yet.) */
8087 tem = fold_truth_not_expr (loc, arg0);
8090 return fold_convert_loc (loc, type, tem);
8093 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8094 return fold_convert_loc (loc, type, arg0);
8095 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8096 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
8097 TREE_OPERAND (arg0, 1));
8098 if (TREE_CODE (arg0) == COMPLEX_CST)
8099 return fold_convert_loc (loc, type, TREE_REALPART (arg0));
8100 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8102 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8103 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8104 fold_build1_loc (loc, REALPART_EXPR, itype,
8105 TREE_OPERAND (arg0, 0)),
8106 fold_build1_loc (loc, REALPART_EXPR, itype,
8107 TREE_OPERAND (arg0, 1)));
8108 return fold_convert_loc (loc, type, tem);
8110 if (TREE_CODE (arg0) == CONJ_EXPR)
8112 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8113 tem = fold_build1_loc (loc, REALPART_EXPR, itype,
8114 TREE_OPERAND (arg0, 0));
8115 return fold_convert_loc (loc, type, tem);
8117 if (TREE_CODE (arg0) == CALL_EXPR)
8119 tree fn = get_callee_fndecl (arg0);
8120 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8121 switch (DECL_FUNCTION_CODE (fn))
8123 CASE_FLT_FN (BUILT_IN_CEXPI):
8124 fn = mathfn_built_in (type, BUILT_IN_COS);
8126 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8136 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8137 return build_zero_cst (type);
8138 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8139 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 1),
8140 TREE_OPERAND (arg0, 0));
8141 if (TREE_CODE (arg0) == COMPLEX_CST)
8142 return fold_convert_loc (loc, type, TREE_IMAGPART (arg0));
8143 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8145 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8146 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8147 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8148 TREE_OPERAND (arg0, 0)),
8149 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8150 TREE_OPERAND (arg0, 1)));
8151 return fold_convert_loc (loc, type, tem);
8153 if (TREE_CODE (arg0) == CONJ_EXPR)
8155 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8156 tem = fold_build1_loc (loc, IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8157 return fold_convert_loc (loc, type, negate_expr (tem));
8159 if (TREE_CODE (arg0) == CALL_EXPR)
8161 tree fn = get_callee_fndecl (arg0);
8162 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8163 switch (DECL_FUNCTION_CODE (fn))
8165 CASE_FLT_FN (BUILT_IN_CEXPI):
8166 fn = mathfn_built_in (type, BUILT_IN_SIN);
8168 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8178 /* Fold *&X to X if X is an lvalue. */
8179 if (TREE_CODE (op0) == ADDR_EXPR)
8181 tree op00 = TREE_OPERAND (op0, 0);
8182 if ((TREE_CODE (op00) == VAR_DECL
8183 || TREE_CODE (op00) == PARM_DECL
8184 || TREE_CODE (op00) == RESULT_DECL)
8185 && !TREE_READONLY (op00))
8192 } /* switch (code) */
8196 /* If the operation was a conversion do _not_ mark a resulting constant
8197 with TREE_OVERFLOW if the original constant was not. These conversions
8198 have implementation defined behavior and retaining the TREE_OVERFLOW
8199 flag here would confuse later passes such as VRP. */
8201 fold_unary_ignore_overflow_loc (location_t loc, enum tree_code code,
8202 tree type, tree op0)
8204 tree res = fold_unary_loc (loc, code, type, op0);
8206 && TREE_CODE (res) == INTEGER_CST
8207 && TREE_CODE (op0) == INTEGER_CST
8208 && CONVERT_EXPR_CODE_P (code))
8209 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8214 /* Fold a binary bitwise/truth expression of code CODE and type TYPE with
8215 operands OP0 and OP1. LOC is the location of the resulting expression.
8216 ARG0 and ARG1 are the NOP_STRIPed results of OP0 and OP1.
8217 Return the folded expression if folding is successful. Otherwise,
8218 return NULL_TREE. */
8220 fold_truth_andor (location_t loc, enum tree_code code, tree type,
8221 tree arg0, tree arg1, tree op0, tree op1)
8225 /* We only do these simplifications if we are optimizing. */
8229 /* Check for things like (A || B) && (A || C). We can convert this
8230 to A || (B && C). Note that either operator can be any of the four
8231 truth and/or operations and the transformation will still be
8232 valid. Also note that we only care about order for the
8233 ANDIF and ORIF operators. If B contains side effects, this
8234 might change the truth-value of A. */
8235 if (TREE_CODE (arg0) == TREE_CODE (arg1)
8236 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
8237 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
8238 || TREE_CODE (arg0) == TRUTH_AND_EXPR
8239 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
8240 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
8242 tree a00 = TREE_OPERAND (arg0, 0);
8243 tree a01 = TREE_OPERAND (arg0, 1);
8244 tree a10 = TREE_OPERAND (arg1, 0);
8245 tree a11 = TREE_OPERAND (arg1, 1);
8246 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
8247 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
8248 && (code == TRUTH_AND_EXPR
8249 || code == TRUTH_OR_EXPR));
8251 if (operand_equal_p (a00, a10, 0))
8252 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
8253 fold_build2_loc (loc, code, type, a01, a11));
8254 else if (commutative && operand_equal_p (a00, a11, 0))
8255 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
8256 fold_build2_loc (loc, code, type, a01, a10));
8257 else if (commutative && operand_equal_p (a01, a10, 0))
8258 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
8259 fold_build2_loc (loc, code, type, a00, a11));
8261 /* This case if tricky because we must either have commutative
8262 operators or else A10 must not have side-effects. */
8264 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
8265 && operand_equal_p (a01, a11, 0))
8266 return fold_build2_loc (loc, TREE_CODE (arg0), type,
8267 fold_build2_loc (loc, code, type, a00, a10),
8271 /* See if we can build a range comparison. */
8272 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
8275 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg0) == TRUTH_ORIF_EXPR)
8276 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg0) == TRUTH_ANDIF_EXPR))
8278 tem = merge_truthop_with_opposite_arm (loc, arg0, arg1, true);
8280 return fold_build2_loc (loc, code, type, tem, arg1);
8283 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg1) == TRUTH_ORIF_EXPR)
8284 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg1) == TRUTH_ANDIF_EXPR))
8286 tem = merge_truthop_with_opposite_arm (loc, arg1, arg0, false);
8288 return fold_build2_loc (loc, code, type, arg0, tem);
8291 /* Check for the possibility of merging component references. If our
8292 lhs is another similar operation, try to merge its rhs with our
8293 rhs. Then try to merge our lhs and rhs. */
8294 if (TREE_CODE (arg0) == code
8295 && 0 != (tem = fold_truthop (loc, code, type,
8296 TREE_OPERAND (arg0, 1), arg1)))
8297 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
8299 if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
8305 /* Fold a binary expression of code CODE and type TYPE with operands
8306 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8307 Return the folded expression if folding is successful. Otherwise,
8308 return NULL_TREE. */
8311 fold_minmax (location_t loc, enum tree_code code, tree type, tree op0, tree op1)
8313 enum tree_code compl_code;
8315 if (code == MIN_EXPR)
8316 compl_code = MAX_EXPR;
8317 else if (code == MAX_EXPR)
8318 compl_code = MIN_EXPR;
8322 /* MIN (MAX (a, b), b) == b. */
8323 if (TREE_CODE (op0) == compl_code
8324 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8325 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 0));
8327 /* MIN (MAX (b, a), b) == b. */
8328 if (TREE_CODE (op0) == compl_code
8329 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8330 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8331 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 1));
8333 /* MIN (a, MAX (a, b)) == a. */
8334 if (TREE_CODE (op1) == compl_code
8335 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8336 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8337 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 1));
8339 /* MIN (a, MAX (b, a)) == a. */
8340 if (TREE_CODE (op1) == compl_code
8341 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8342 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8343 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 0));
8348 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8349 by changing CODE to reduce the magnitude of constants involved in
8350 ARG0 of the comparison.
8351 Returns a canonicalized comparison tree if a simplification was
8352 possible, otherwise returns NULL_TREE.
8353 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8354 valid if signed overflow is undefined. */
8357 maybe_canonicalize_comparison_1 (location_t loc, enum tree_code code, tree type,
8358 tree arg0, tree arg1,
8359 bool *strict_overflow_p)
8361 enum tree_code code0 = TREE_CODE (arg0);
8362 tree t, cst0 = NULL_TREE;
8366 /* Match A +- CST code arg1 and CST code arg1. We can change the
8367 first form only if overflow is undefined. */
8368 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8369 /* In principle pointers also have undefined overflow behavior,
8370 but that causes problems elsewhere. */
8371 && !POINTER_TYPE_P (TREE_TYPE (arg0))
8372 && (code0 == MINUS_EXPR
8373 || code0 == PLUS_EXPR)
8374 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8375 || code0 == INTEGER_CST))
8378 /* Identify the constant in arg0 and its sign. */
8379 if (code0 == INTEGER_CST)
8382 cst0 = TREE_OPERAND (arg0, 1);
8383 sgn0 = tree_int_cst_sgn (cst0);
8385 /* Overflowed constants and zero will cause problems. */
8386 if (integer_zerop (cst0)
8387 || TREE_OVERFLOW (cst0))
8390 /* See if we can reduce the magnitude of the constant in
8391 arg0 by changing the comparison code. */
8392 if (code0 == INTEGER_CST)
8394 /* CST <= arg1 -> CST-1 < arg1. */
8395 if (code == LE_EXPR && sgn0 == 1)
8397 /* -CST < arg1 -> -CST-1 <= arg1. */
8398 else if (code == LT_EXPR && sgn0 == -1)
8400 /* CST > arg1 -> CST-1 >= arg1. */
8401 else if (code == GT_EXPR && sgn0 == 1)
8403 /* -CST >= arg1 -> -CST-1 > arg1. */
8404 else if (code == GE_EXPR && sgn0 == -1)
8408 /* arg1 code' CST' might be more canonical. */
8413 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8415 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8417 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8418 else if (code == GT_EXPR
8419 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8421 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8422 else if (code == LE_EXPR
8423 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8425 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8426 else if (code == GE_EXPR
8427 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8431 *strict_overflow_p = true;
8434 /* Now build the constant reduced in magnitude. But not if that
8435 would produce one outside of its types range. */
8436 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
8438 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
8439 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
8441 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
8442 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
8443 /* We cannot swap the comparison here as that would cause us to
8444 endlessly recurse. */
8447 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8448 cst0, build_int_cst (TREE_TYPE (cst0), 1));
8449 if (code0 != INTEGER_CST)
8450 t = fold_build2_loc (loc, code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8452 /* If swapping might yield to a more canonical form, do so. */
8454 return fold_build2_loc (loc, swap_tree_comparison (code), type, arg1, t);
8456 return fold_build2_loc (loc, code, type, t, arg1);
8459 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8460 overflow further. Try to decrease the magnitude of constants involved
8461 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8462 and put sole constants at the second argument position.
8463 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8466 maybe_canonicalize_comparison (location_t loc, enum tree_code code, tree type,
8467 tree arg0, tree arg1)
8470 bool strict_overflow_p;
8471 const char * const warnmsg = G_("assuming signed overflow does not occur "
8472 "when reducing constant in comparison");
8474 /* Try canonicalization by simplifying arg0. */
8475 strict_overflow_p = false;
8476 t = maybe_canonicalize_comparison_1 (loc, code, type, arg0, arg1,
8477 &strict_overflow_p);
8480 if (strict_overflow_p)
8481 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8485 /* Try canonicalization by simplifying arg1 using the swapped
8487 code = swap_tree_comparison (code);
8488 strict_overflow_p = false;
8489 t = maybe_canonicalize_comparison_1 (loc, code, type, arg1, arg0,
8490 &strict_overflow_p);
8491 if (t && strict_overflow_p)
8492 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8496 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8497 space. This is used to avoid issuing overflow warnings for
8498 expressions like &p->x which can not wrap. */
8501 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8503 unsigned HOST_WIDE_INT offset_low, total_low;
8504 HOST_WIDE_INT size, offset_high, total_high;
8506 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8512 if (offset == NULL_TREE)
8517 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8521 offset_low = TREE_INT_CST_LOW (offset);
8522 offset_high = TREE_INT_CST_HIGH (offset);
8525 if (add_double_with_sign (offset_low, offset_high,
8526 bitpos / BITS_PER_UNIT, 0,
8527 &total_low, &total_high,
8531 if (total_high != 0)
8534 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8538 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8540 if (TREE_CODE (base) == ADDR_EXPR)
8542 HOST_WIDE_INT base_size;
8544 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8545 if (base_size > 0 && size < base_size)
8549 return total_low > (unsigned HOST_WIDE_INT) size;
8552 /* Subroutine of fold_binary. This routine performs all of the
8553 transformations that are common to the equality/inequality
8554 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8555 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8556 fold_binary should call fold_binary. Fold a comparison with
8557 tree code CODE and type TYPE with operands OP0 and OP1. Return
8558 the folded comparison or NULL_TREE. */
8561 fold_comparison (location_t loc, enum tree_code code, tree type,
8564 tree arg0, arg1, tem;
8569 STRIP_SIGN_NOPS (arg0);
8570 STRIP_SIGN_NOPS (arg1);
8572 tem = fold_relational_const (code, type, arg0, arg1);
8573 if (tem != NULL_TREE)
8576 /* If one arg is a real or integer constant, put it last. */
8577 if (tree_swap_operands_p (arg0, arg1, true))
8578 return fold_build2_loc (loc, swap_tree_comparison (code), type, op1, op0);
8580 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8581 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8582 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8583 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8584 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8585 && (TREE_CODE (arg1) == INTEGER_CST
8586 && !TREE_OVERFLOW (arg1)))
8588 tree const1 = TREE_OPERAND (arg0, 1);
8590 tree variable = TREE_OPERAND (arg0, 0);
8593 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8595 lhs = fold_build2_loc (loc, lhs_add ? PLUS_EXPR : MINUS_EXPR,
8596 TREE_TYPE (arg1), const2, const1);
8598 /* If the constant operation overflowed this can be
8599 simplified as a comparison against INT_MAX/INT_MIN. */
8600 if (TREE_CODE (lhs) == INTEGER_CST
8601 && TREE_OVERFLOW (lhs))
8603 int const1_sgn = tree_int_cst_sgn (const1);
8604 enum tree_code code2 = code;
8606 /* Get the sign of the constant on the lhs if the
8607 operation were VARIABLE + CONST1. */
8608 if (TREE_CODE (arg0) == MINUS_EXPR)
8609 const1_sgn = -const1_sgn;
8611 /* The sign of the constant determines if we overflowed
8612 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8613 Canonicalize to the INT_MIN overflow by swapping the comparison
8615 if (const1_sgn == -1)
8616 code2 = swap_tree_comparison (code);
8618 /* We now can look at the canonicalized case
8619 VARIABLE + 1 CODE2 INT_MIN
8620 and decide on the result. */
8621 if (code2 == LT_EXPR
8623 || code2 == EQ_EXPR)
8624 return omit_one_operand_loc (loc, type, boolean_false_node, variable);
8625 else if (code2 == NE_EXPR
8627 || code2 == GT_EXPR)
8628 return omit_one_operand_loc (loc, type, boolean_true_node, variable);
8631 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8632 && (TREE_CODE (lhs) != INTEGER_CST
8633 || !TREE_OVERFLOW (lhs)))
8635 if (code != EQ_EXPR && code != NE_EXPR)
8636 fold_overflow_warning ("assuming signed overflow does not occur "
8637 "when changing X +- C1 cmp C2 to "
8639 WARN_STRICT_OVERFLOW_COMPARISON);
8640 return fold_build2_loc (loc, code, type, variable, lhs);
8644 /* For comparisons of pointers we can decompose it to a compile time
8645 comparison of the base objects and the offsets into the object.
8646 This requires at least one operand being an ADDR_EXPR or a
8647 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8648 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8649 && (TREE_CODE (arg0) == ADDR_EXPR
8650 || TREE_CODE (arg1) == ADDR_EXPR
8651 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8652 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8654 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8655 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8656 enum machine_mode mode;
8657 int volatilep, unsignedp;
8658 bool indirect_base0 = false, indirect_base1 = false;
8660 /* Get base and offset for the access. Strip ADDR_EXPR for
8661 get_inner_reference, but put it back by stripping INDIRECT_REF
8662 off the base object if possible. indirect_baseN will be true
8663 if baseN is not an address but refers to the object itself. */
8665 if (TREE_CODE (arg0) == ADDR_EXPR)
8667 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8668 &bitsize, &bitpos0, &offset0, &mode,
8669 &unsignedp, &volatilep, false);
8670 if (TREE_CODE (base0) == INDIRECT_REF)
8671 base0 = TREE_OPERAND (base0, 0);
8673 indirect_base0 = true;
8675 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
8677 base0 = TREE_OPERAND (arg0, 0);
8678 STRIP_SIGN_NOPS (base0);
8679 if (TREE_CODE (base0) == ADDR_EXPR)
8681 base0 = TREE_OPERAND (base0, 0);
8682 indirect_base0 = true;
8684 offset0 = TREE_OPERAND (arg0, 1);
8688 if (TREE_CODE (arg1) == ADDR_EXPR)
8690 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
8691 &bitsize, &bitpos1, &offset1, &mode,
8692 &unsignedp, &volatilep, false);
8693 if (TREE_CODE (base1) == INDIRECT_REF)
8694 base1 = TREE_OPERAND (base1, 0);
8696 indirect_base1 = true;
8698 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
8700 base1 = TREE_OPERAND (arg1, 0);
8701 STRIP_SIGN_NOPS (base1);
8702 if (TREE_CODE (base1) == ADDR_EXPR)
8704 base1 = TREE_OPERAND (base1, 0);
8705 indirect_base1 = true;
8707 offset1 = TREE_OPERAND (arg1, 1);
8710 /* A local variable can never be pointed to by
8711 the default SSA name of an incoming parameter. */
8712 if ((TREE_CODE (arg0) == ADDR_EXPR
8714 && TREE_CODE (base0) == VAR_DECL
8715 && auto_var_in_fn_p (base0, current_function_decl)
8717 && TREE_CODE (base1) == SSA_NAME
8718 && TREE_CODE (SSA_NAME_VAR (base1)) == PARM_DECL
8719 && SSA_NAME_IS_DEFAULT_DEF (base1))
8720 || (TREE_CODE (arg1) == ADDR_EXPR
8722 && TREE_CODE (base1) == VAR_DECL
8723 && auto_var_in_fn_p (base1, current_function_decl)
8725 && TREE_CODE (base0) == SSA_NAME
8726 && TREE_CODE (SSA_NAME_VAR (base0)) == PARM_DECL
8727 && SSA_NAME_IS_DEFAULT_DEF (base0)))
8729 if (code == NE_EXPR)
8730 return constant_boolean_node (1, type);
8731 else if (code == EQ_EXPR)
8732 return constant_boolean_node (0, type);
8734 /* If we have equivalent bases we might be able to simplify. */
8735 else if (indirect_base0 == indirect_base1
8736 && operand_equal_p (base0, base1, 0))
8738 /* We can fold this expression to a constant if the non-constant
8739 offset parts are equal. */
8740 if ((offset0 == offset1
8741 || (offset0 && offset1
8742 && operand_equal_p (offset0, offset1, 0)))
8745 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8750 && bitpos0 != bitpos1
8751 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8752 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8753 fold_overflow_warning (("assuming pointer wraparound does not "
8754 "occur when comparing P +- C1 with "
8756 WARN_STRICT_OVERFLOW_CONDITIONAL);
8761 return constant_boolean_node (bitpos0 == bitpos1, type);
8763 return constant_boolean_node (bitpos0 != bitpos1, type);
8765 return constant_boolean_node (bitpos0 < bitpos1, type);
8767 return constant_boolean_node (bitpos0 <= bitpos1, type);
8769 return constant_boolean_node (bitpos0 >= bitpos1, type);
8771 return constant_boolean_node (bitpos0 > bitpos1, type);
8775 /* We can simplify the comparison to a comparison of the variable
8776 offset parts if the constant offset parts are equal.
8777 Be careful to use signed size type here because otherwise we
8778 mess with array offsets in the wrong way. This is possible
8779 because pointer arithmetic is restricted to retain within an
8780 object and overflow on pointer differences is undefined as of
8781 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
8782 else if (bitpos0 == bitpos1
8783 && ((code == EQ_EXPR || code == NE_EXPR)
8784 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8786 /* By converting to signed size type we cover middle-end pointer
8787 arithmetic which operates on unsigned pointer types of size
8788 type size and ARRAY_REF offsets which are properly sign or
8789 zero extended from their type in case it is narrower than
8791 if (offset0 == NULL_TREE)
8792 offset0 = build_int_cst (ssizetype, 0);
8794 offset0 = fold_convert_loc (loc, ssizetype, offset0);
8795 if (offset1 == NULL_TREE)
8796 offset1 = build_int_cst (ssizetype, 0);
8798 offset1 = fold_convert_loc (loc, ssizetype, offset1);
8802 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8803 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8804 fold_overflow_warning (("assuming pointer wraparound does not "
8805 "occur when comparing P +- C1 with "
8807 WARN_STRICT_OVERFLOW_COMPARISON);
8809 return fold_build2_loc (loc, code, type, offset0, offset1);
8812 /* For non-equal bases we can simplify if they are addresses
8813 of local binding decls or constants. */
8814 else if (indirect_base0 && indirect_base1
8815 /* We know that !operand_equal_p (base0, base1, 0)
8816 because the if condition was false. But make
8817 sure two decls are not the same. */
8819 && TREE_CODE (arg0) == ADDR_EXPR
8820 && TREE_CODE (arg1) == ADDR_EXPR
8821 && (((TREE_CODE (base0) == VAR_DECL
8822 || TREE_CODE (base0) == PARM_DECL)
8823 && (targetm.binds_local_p (base0)
8824 || CONSTANT_CLASS_P (base1)))
8825 || CONSTANT_CLASS_P (base0))
8826 && (((TREE_CODE (base1) == VAR_DECL
8827 || TREE_CODE (base1) == PARM_DECL)
8828 && (targetm.binds_local_p (base1)
8829 || CONSTANT_CLASS_P (base0)))
8830 || CONSTANT_CLASS_P (base1)))
8832 if (code == EQ_EXPR)
8833 return omit_two_operands_loc (loc, type, boolean_false_node,
8835 else if (code == NE_EXPR)
8836 return omit_two_operands_loc (loc, type, boolean_true_node,
8839 /* For equal offsets we can simplify to a comparison of the
8841 else if (bitpos0 == bitpos1
8843 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
8845 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
8846 && ((offset0 == offset1)
8847 || (offset0 && offset1
8848 && operand_equal_p (offset0, offset1, 0))))
8851 base0 = build_fold_addr_expr_loc (loc, base0);
8853 base1 = build_fold_addr_expr_loc (loc, base1);
8854 return fold_build2_loc (loc, code, type, base0, base1);
8858 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
8859 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
8860 the resulting offset is smaller in absolute value than the
8862 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8863 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8864 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8865 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8866 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
8867 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
8868 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
8870 tree const1 = TREE_OPERAND (arg0, 1);
8871 tree const2 = TREE_OPERAND (arg1, 1);
8872 tree variable1 = TREE_OPERAND (arg0, 0);
8873 tree variable2 = TREE_OPERAND (arg1, 0);
8875 const char * const warnmsg = G_("assuming signed overflow does not "
8876 "occur when combining constants around "
8879 /* Put the constant on the side where it doesn't overflow and is
8880 of lower absolute value than before. */
8881 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8882 ? MINUS_EXPR : PLUS_EXPR,
8884 if (!TREE_OVERFLOW (cst)
8885 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
8887 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8888 return fold_build2_loc (loc, code, type,
8890 fold_build2_loc (loc,
8891 TREE_CODE (arg1), TREE_TYPE (arg1),
8895 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8896 ? MINUS_EXPR : PLUS_EXPR,
8898 if (!TREE_OVERFLOW (cst)
8899 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
8901 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8902 return fold_build2_loc (loc, code, type,
8903 fold_build2_loc (loc, TREE_CODE (arg0), TREE_TYPE (arg0),
8909 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
8910 signed arithmetic case. That form is created by the compiler
8911 often enough for folding it to be of value. One example is in
8912 computing loop trip counts after Operator Strength Reduction. */
8913 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8914 && TREE_CODE (arg0) == MULT_EXPR
8915 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8916 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8917 && integer_zerop (arg1))
8919 tree const1 = TREE_OPERAND (arg0, 1);
8920 tree const2 = arg1; /* zero */
8921 tree variable1 = TREE_OPERAND (arg0, 0);
8922 enum tree_code cmp_code = code;
8924 /* Handle unfolded multiplication by zero. */
8925 if (integer_zerop (const1))
8926 return fold_build2_loc (loc, cmp_code, type, const1, const2);
8928 fold_overflow_warning (("assuming signed overflow does not occur when "
8929 "eliminating multiplication in comparison "
8931 WARN_STRICT_OVERFLOW_COMPARISON);
8933 /* If const1 is negative we swap the sense of the comparison. */
8934 if (tree_int_cst_sgn (const1) < 0)
8935 cmp_code = swap_tree_comparison (cmp_code);
8937 return fold_build2_loc (loc, cmp_code, type, variable1, const2);
8940 tem = maybe_canonicalize_comparison (loc, code, type, op0, op1);
8944 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
8946 tree targ0 = strip_float_extensions (arg0);
8947 tree targ1 = strip_float_extensions (arg1);
8948 tree newtype = TREE_TYPE (targ0);
8950 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
8951 newtype = TREE_TYPE (targ1);
8953 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
8954 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
8955 return fold_build2_loc (loc, code, type,
8956 fold_convert_loc (loc, newtype, targ0),
8957 fold_convert_loc (loc, newtype, targ1));
8959 /* (-a) CMP (-b) -> b CMP a */
8960 if (TREE_CODE (arg0) == NEGATE_EXPR
8961 && TREE_CODE (arg1) == NEGATE_EXPR)
8962 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg1, 0),
8963 TREE_OPERAND (arg0, 0));
8965 if (TREE_CODE (arg1) == REAL_CST)
8967 REAL_VALUE_TYPE cst;
8968 cst = TREE_REAL_CST (arg1);
8970 /* (-a) CMP CST -> a swap(CMP) (-CST) */
8971 if (TREE_CODE (arg0) == NEGATE_EXPR)
8972 return fold_build2_loc (loc, swap_tree_comparison (code), type,
8973 TREE_OPERAND (arg0, 0),
8974 build_real (TREE_TYPE (arg1),
8975 real_value_negate (&cst)));
8977 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
8978 /* a CMP (-0) -> a CMP 0 */
8979 if (REAL_VALUE_MINUS_ZERO (cst))
8980 return fold_build2_loc (loc, code, type, arg0,
8981 build_real (TREE_TYPE (arg1), dconst0));
8983 /* x != NaN is always true, other ops are always false. */
8984 if (REAL_VALUE_ISNAN (cst)
8985 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
8987 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
8988 return omit_one_operand_loc (loc, type, tem, arg0);
8991 /* Fold comparisons against infinity. */
8992 if (REAL_VALUE_ISINF (cst)
8993 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
8995 tem = fold_inf_compare (loc, code, type, arg0, arg1);
8996 if (tem != NULL_TREE)
9001 /* If this is a comparison of a real constant with a PLUS_EXPR
9002 or a MINUS_EXPR of a real constant, we can convert it into a
9003 comparison with a revised real constant as long as no overflow
9004 occurs when unsafe_math_optimizations are enabled. */
9005 if (flag_unsafe_math_optimizations
9006 && TREE_CODE (arg1) == REAL_CST
9007 && (TREE_CODE (arg0) == PLUS_EXPR
9008 || TREE_CODE (arg0) == MINUS_EXPR)
9009 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9010 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9011 ? MINUS_EXPR : PLUS_EXPR,
9012 arg1, TREE_OPERAND (arg0, 1)))
9013 && !TREE_OVERFLOW (tem))
9014 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
9016 /* Likewise, we can simplify a comparison of a real constant with
9017 a MINUS_EXPR whose first operand is also a real constant, i.e.
9018 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9019 floating-point types only if -fassociative-math is set. */
9020 if (flag_associative_math
9021 && TREE_CODE (arg1) == REAL_CST
9022 && TREE_CODE (arg0) == MINUS_EXPR
9023 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9024 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9026 && !TREE_OVERFLOW (tem))
9027 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9028 TREE_OPERAND (arg0, 1), tem);
9030 /* Fold comparisons against built-in math functions. */
9031 if (TREE_CODE (arg1) == REAL_CST
9032 && flag_unsafe_math_optimizations
9033 && ! flag_errno_math)
9035 enum built_in_function fcode = builtin_mathfn_code (arg0);
9037 if (fcode != END_BUILTINS)
9039 tem = fold_mathfn_compare (loc, fcode, code, type, arg0, arg1);
9040 if (tem != NULL_TREE)
9046 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9047 && CONVERT_EXPR_P (arg0))
9049 /* If we are widening one operand of an integer comparison,
9050 see if the other operand is similarly being widened. Perhaps we
9051 can do the comparison in the narrower type. */
9052 tem = fold_widened_comparison (loc, code, type, arg0, arg1);
9056 /* Or if we are changing signedness. */
9057 tem = fold_sign_changed_comparison (loc, code, type, arg0, arg1);
9062 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9063 constant, we can simplify it. */
9064 if (TREE_CODE (arg1) == INTEGER_CST
9065 && (TREE_CODE (arg0) == MIN_EXPR
9066 || TREE_CODE (arg0) == MAX_EXPR)
9067 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9069 tem = optimize_minmax_comparison (loc, code, type, op0, op1);
9074 /* Simplify comparison of something with itself. (For IEEE
9075 floating-point, we can only do some of these simplifications.) */
9076 if (operand_equal_p (arg0, arg1, 0))
9081 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9082 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9083 return constant_boolean_node (1, type);
9088 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9089 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9090 return constant_boolean_node (1, type);
9091 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg1);
9094 /* For NE, we can only do this simplification if integer
9095 or we don't honor IEEE floating point NaNs. */
9096 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9097 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9099 /* ... fall through ... */
9102 return constant_boolean_node (0, type);
9108 /* If we are comparing an expression that just has comparisons
9109 of two integer values, arithmetic expressions of those comparisons,
9110 and constants, we can simplify it. There are only three cases
9111 to check: the two values can either be equal, the first can be
9112 greater, or the second can be greater. Fold the expression for
9113 those three values. Since each value must be 0 or 1, we have
9114 eight possibilities, each of which corresponds to the constant 0
9115 or 1 or one of the six possible comparisons.
9117 This handles common cases like (a > b) == 0 but also handles
9118 expressions like ((x > y) - (y > x)) > 0, which supposedly
9119 occur in macroized code. */
9121 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9123 tree cval1 = 0, cval2 = 0;
9126 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9127 /* Don't handle degenerate cases here; they should already
9128 have been handled anyway. */
9129 && cval1 != 0 && cval2 != 0
9130 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9131 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9132 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9133 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9134 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9135 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9136 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9138 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9139 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9141 /* We can't just pass T to eval_subst in case cval1 or cval2
9142 was the same as ARG1. */
9145 = fold_build2_loc (loc, code, type,
9146 eval_subst (loc, arg0, cval1, maxval,
9150 = fold_build2_loc (loc, code, type,
9151 eval_subst (loc, arg0, cval1, maxval,
9155 = fold_build2_loc (loc, code, type,
9156 eval_subst (loc, arg0, cval1, minval,
9160 /* All three of these results should be 0 or 1. Confirm they are.
9161 Then use those values to select the proper code to use. */
9163 if (TREE_CODE (high_result) == INTEGER_CST
9164 && TREE_CODE (equal_result) == INTEGER_CST
9165 && TREE_CODE (low_result) == INTEGER_CST)
9167 /* Make a 3-bit mask with the high-order bit being the
9168 value for `>', the next for '=', and the low for '<'. */
9169 switch ((integer_onep (high_result) * 4)
9170 + (integer_onep (equal_result) * 2)
9171 + integer_onep (low_result))
9175 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
9196 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
9201 tem = save_expr (build2 (code, type, cval1, cval2));
9202 SET_EXPR_LOCATION (tem, loc);
9205 return fold_build2_loc (loc, code, type, cval1, cval2);
9210 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9211 into a single range test. */
9212 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9213 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9214 && TREE_CODE (arg1) == INTEGER_CST
9215 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9216 && !integer_zerop (TREE_OPERAND (arg0, 1))
9217 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9218 && !TREE_OVERFLOW (arg1))
9220 tem = fold_div_compare (loc, code, type, arg0, arg1);
9221 if (tem != NULL_TREE)
9225 /* Fold ~X op ~Y as Y op X. */
9226 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9227 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9229 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9230 return fold_build2_loc (loc, code, type,
9231 fold_convert_loc (loc, cmp_type,
9232 TREE_OPERAND (arg1, 0)),
9233 TREE_OPERAND (arg0, 0));
9236 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9237 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9238 && TREE_CODE (arg1) == INTEGER_CST)
9240 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9241 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9242 TREE_OPERAND (arg0, 0),
9243 fold_build1_loc (loc, BIT_NOT_EXPR, cmp_type,
9244 fold_convert_loc (loc, cmp_type, arg1)));
9251 /* Subroutine of fold_binary. Optimize complex multiplications of the
9252 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9253 argument EXPR represents the expression "z" of type TYPE. */
9256 fold_mult_zconjz (location_t loc, tree type, tree expr)
9258 tree itype = TREE_TYPE (type);
9259 tree rpart, ipart, tem;
9261 if (TREE_CODE (expr) == COMPLEX_EXPR)
9263 rpart = TREE_OPERAND (expr, 0);
9264 ipart = TREE_OPERAND (expr, 1);
9266 else if (TREE_CODE (expr) == COMPLEX_CST)
9268 rpart = TREE_REALPART (expr);
9269 ipart = TREE_IMAGPART (expr);
9273 expr = save_expr (expr);
9274 rpart = fold_build1_loc (loc, REALPART_EXPR, itype, expr);
9275 ipart = fold_build1_loc (loc, IMAGPART_EXPR, itype, expr);
9278 rpart = save_expr (rpart);
9279 ipart = save_expr (ipart);
9280 tem = fold_build2_loc (loc, PLUS_EXPR, itype,
9281 fold_build2_loc (loc, MULT_EXPR, itype, rpart, rpart),
9282 fold_build2_loc (loc, MULT_EXPR, itype, ipart, ipart));
9283 return fold_build2_loc (loc, COMPLEX_EXPR, type, tem,
9284 build_zero_cst (itype));
9288 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9289 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9290 guarantees that P and N have the same least significant log2(M) bits.
9291 N is not otherwise constrained. In particular, N is not normalized to
9292 0 <= N < M as is common. In general, the precise value of P is unknown.
9293 M is chosen as large as possible such that constant N can be determined.
9295 Returns M and sets *RESIDUE to N.
9297 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9298 account. This is not always possible due to PR 35705.
9301 static unsigned HOST_WIDE_INT
9302 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9303 bool allow_func_align)
9305 enum tree_code code;
9309 code = TREE_CODE (expr);
9310 if (code == ADDR_EXPR)
9312 unsigned int bitalign;
9313 bitalign = get_object_alignment_1 (TREE_OPERAND (expr, 0), residue);
9314 *residue /= BITS_PER_UNIT;
9315 return bitalign / BITS_PER_UNIT;
9317 else if (code == POINTER_PLUS_EXPR)
9320 unsigned HOST_WIDE_INT modulus;
9321 enum tree_code inner_code;
9323 op0 = TREE_OPERAND (expr, 0);
9325 modulus = get_pointer_modulus_and_residue (op0, residue,
9328 op1 = TREE_OPERAND (expr, 1);
9330 inner_code = TREE_CODE (op1);
9331 if (inner_code == INTEGER_CST)
9333 *residue += TREE_INT_CST_LOW (op1);
9336 else if (inner_code == MULT_EXPR)
9338 op1 = TREE_OPERAND (op1, 1);
9339 if (TREE_CODE (op1) == INTEGER_CST)
9341 unsigned HOST_WIDE_INT align;
9343 /* Compute the greatest power-of-2 divisor of op1. */
9344 align = TREE_INT_CST_LOW (op1);
9347 /* If align is non-zero and less than *modulus, replace
9348 *modulus with align., If align is 0, then either op1 is 0
9349 or the greatest power-of-2 divisor of op1 doesn't fit in an
9350 unsigned HOST_WIDE_INT. In either case, no additional
9351 constraint is imposed. */
9353 modulus = MIN (modulus, align);
9360 /* If we get here, we were unable to determine anything useful about the
9366 /* Fold a binary expression of code CODE and type TYPE with operands
9367 OP0 and OP1. LOC is the location of the resulting expression.
9368 Return the folded expression if folding is successful. Otherwise,
9369 return NULL_TREE. */
9372 fold_binary_loc (location_t loc,
9373 enum tree_code code, tree type, tree op0, tree op1)
9375 enum tree_code_class kind = TREE_CODE_CLASS (code);
9376 tree arg0, arg1, tem;
9377 tree t1 = NULL_TREE;
9378 bool strict_overflow_p;
9380 gcc_assert (IS_EXPR_CODE_CLASS (kind)
9381 && TREE_CODE_LENGTH (code) == 2
9383 && op1 != NULL_TREE);
9388 /* Strip any conversions that don't change the mode. This is
9389 safe for every expression, except for a comparison expression
9390 because its signedness is derived from its operands. So, in
9391 the latter case, only strip conversions that don't change the
9392 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
9395 Note that this is done as an internal manipulation within the
9396 constant folder, in order to find the simplest representation
9397 of the arguments so that their form can be studied. In any
9398 cases, the appropriate type conversions should be put back in
9399 the tree that will get out of the constant folder. */
9401 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
9403 STRIP_SIGN_NOPS (arg0);
9404 STRIP_SIGN_NOPS (arg1);
9412 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9413 constant but we can't do arithmetic on them. */
9414 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9415 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9416 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9417 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9418 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9419 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9421 if (kind == tcc_binary)
9423 /* Make sure type and arg0 have the same saturating flag. */
9424 gcc_assert (TYPE_SATURATING (type)
9425 == TYPE_SATURATING (TREE_TYPE (arg0)));
9426 tem = const_binop (code, arg0, arg1);
9428 else if (kind == tcc_comparison)
9429 tem = fold_relational_const (code, type, arg0, arg1);
9433 if (tem != NULL_TREE)
9435 if (TREE_TYPE (tem) != type)
9436 tem = fold_convert_loc (loc, type, tem);
9441 /* If this is a commutative operation, and ARG0 is a constant, move it
9442 to ARG1 to reduce the number of tests below. */
9443 if (commutative_tree_code (code)
9444 && tree_swap_operands_p (arg0, arg1, true))
9445 return fold_build2_loc (loc, code, type, op1, op0);
9447 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9449 First check for cases where an arithmetic operation is applied to a
9450 compound, conditional, or comparison operation. Push the arithmetic
9451 operation inside the compound or conditional to see if any folding
9452 can then be done. Convert comparison to conditional for this purpose.
9453 The also optimizes non-constant cases that used to be done in
9456 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9457 one of the operands is a comparison and the other is a comparison, a
9458 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9459 code below would make the expression more complex. Change it to a
9460 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9461 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9463 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9464 || code == EQ_EXPR || code == NE_EXPR)
9465 && ((truth_value_p (TREE_CODE (arg0))
9466 && (truth_value_p (TREE_CODE (arg1))
9467 || (TREE_CODE (arg1) == BIT_AND_EXPR
9468 && integer_onep (TREE_OPERAND (arg1, 1)))))
9469 || (truth_value_p (TREE_CODE (arg1))
9470 && (truth_value_p (TREE_CODE (arg0))
9471 || (TREE_CODE (arg0) == BIT_AND_EXPR
9472 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9474 tem = fold_build2_loc (loc, code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9475 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9478 fold_convert_loc (loc, boolean_type_node, arg0),
9479 fold_convert_loc (loc, boolean_type_node, arg1));
9481 if (code == EQ_EXPR)
9482 tem = invert_truthvalue_loc (loc, tem);
9484 return fold_convert_loc (loc, type, tem);
9487 if (TREE_CODE_CLASS (code) == tcc_binary
9488 || TREE_CODE_CLASS (code) == tcc_comparison)
9490 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9492 tem = fold_build2_loc (loc, code, type,
9493 fold_convert_loc (loc, TREE_TYPE (op0),
9494 TREE_OPERAND (arg0, 1)), op1);
9495 return build2_loc (loc, COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
9498 if (TREE_CODE (arg1) == COMPOUND_EXPR
9499 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9501 tem = fold_build2_loc (loc, code, type, op0,
9502 fold_convert_loc (loc, TREE_TYPE (op1),
9503 TREE_OPERAND (arg1, 1)));
9504 return build2_loc (loc, COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0),
9508 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9510 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9512 /*cond_first_p=*/1);
9513 if (tem != NULL_TREE)
9517 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9519 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9521 /*cond_first_p=*/0);
9522 if (tem != NULL_TREE)
9530 /* MEM[&MEM[p, CST1], CST2] -> MEM[p, CST1 + CST2]. */
9531 if (TREE_CODE (arg0) == ADDR_EXPR
9532 && TREE_CODE (TREE_OPERAND (arg0, 0)) == MEM_REF)
9534 tree iref = TREE_OPERAND (arg0, 0);
9535 return fold_build2 (MEM_REF, type,
9536 TREE_OPERAND (iref, 0),
9537 int_const_binop (PLUS_EXPR, arg1,
9538 TREE_OPERAND (iref, 1)));
9541 /* MEM[&a.b, CST2] -> MEM[&a, offsetof (a, b) + CST2]. */
9542 if (TREE_CODE (arg0) == ADDR_EXPR
9543 && handled_component_p (TREE_OPERAND (arg0, 0)))
9546 HOST_WIDE_INT coffset;
9547 base = get_addr_base_and_unit_offset (TREE_OPERAND (arg0, 0),
9551 return fold_build2 (MEM_REF, type,
9552 build_fold_addr_expr (base),
9553 int_const_binop (PLUS_EXPR, arg1,
9554 size_int (coffset)));
9559 case POINTER_PLUS_EXPR:
9560 /* 0 +p index -> (type)index */
9561 if (integer_zerop (arg0))
9562 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9564 /* PTR +p 0 -> PTR */
9565 if (integer_zerop (arg1))
9566 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9568 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9569 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9570 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9571 return fold_convert_loc (loc, type,
9572 fold_build2_loc (loc, PLUS_EXPR, sizetype,
9573 fold_convert_loc (loc, sizetype,
9575 fold_convert_loc (loc, sizetype,
9578 /* index +p PTR -> PTR +p index */
9579 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9580 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9581 return fold_build2_loc (loc, POINTER_PLUS_EXPR, type,
9582 fold_convert_loc (loc, type, arg1),
9583 fold_convert_loc (loc, sizetype, arg0));
9585 /* (PTR +p B) +p A -> PTR +p (B + A) */
9586 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9589 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
9590 tree arg00 = TREE_OPERAND (arg0, 0);
9591 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
9592 arg01, fold_convert_loc (loc, sizetype, arg1));
9593 return fold_convert_loc (loc, type,
9594 fold_build2_loc (loc, POINTER_PLUS_EXPR,
9599 /* PTR_CST +p CST -> CST1 */
9600 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9601 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
9602 fold_convert_loc (loc, type, arg1));
9604 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9605 of the array. Loop optimizer sometimes produce this type of
9607 if (TREE_CODE (arg0) == ADDR_EXPR)
9609 tem = try_move_mult_to_index (loc, arg0,
9610 fold_convert_loc (loc, sizetype, arg1));
9612 return fold_convert_loc (loc, type, tem);
9618 /* A + (-B) -> A - B */
9619 if (TREE_CODE (arg1) == NEGATE_EXPR)
9620 return fold_build2_loc (loc, MINUS_EXPR, type,
9621 fold_convert_loc (loc, type, arg0),
9622 fold_convert_loc (loc, type,
9623 TREE_OPERAND (arg1, 0)));
9624 /* (-A) + B -> B - A */
9625 if (TREE_CODE (arg0) == NEGATE_EXPR
9626 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9627 return fold_build2_loc (loc, MINUS_EXPR, type,
9628 fold_convert_loc (loc, type, arg1),
9629 fold_convert_loc (loc, type,
9630 TREE_OPERAND (arg0, 0)));
9632 if (INTEGRAL_TYPE_P (type))
9634 /* Convert ~A + 1 to -A. */
9635 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9636 && integer_onep (arg1))
9637 return fold_build1_loc (loc, NEGATE_EXPR, type,
9638 fold_convert_loc (loc, type,
9639 TREE_OPERAND (arg0, 0)));
9642 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9643 && !TYPE_OVERFLOW_TRAPS (type))
9645 tree tem = TREE_OPERAND (arg0, 0);
9648 if (operand_equal_p (tem, arg1, 0))
9650 t1 = build_int_cst_type (type, -1);
9651 return omit_one_operand_loc (loc, type, t1, arg1);
9656 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9657 && !TYPE_OVERFLOW_TRAPS (type))
9659 tree tem = TREE_OPERAND (arg1, 0);
9662 if (operand_equal_p (arg0, tem, 0))
9664 t1 = build_int_cst_type (type, -1);
9665 return omit_one_operand_loc (loc, type, t1, arg0);
9669 /* X + (X / CST) * -CST is X % CST. */
9670 if (TREE_CODE (arg1) == MULT_EXPR
9671 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9672 && operand_equal_p (arg0,
9673 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9675 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9676 tree cst1 = TREE_OPERAND (arg1, 1);
9677 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
9679 if (sum && integer_zerop (sum))
9680 return fold_convert_loc (loc, type,
9681 fold_build2_loc (loc, TRUNC_MOD_EXPR,
9682 TREE_TYPE (arg0), arg0,
9687 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9688 same or one. Make sure type is not saturating.
9689 fold_plusminus_mult_expr will re-associate. */
9690 if ((TREE_CODE (arg0) == MULT_EXPR
9691 || TREE_CODE (arg1) == MULT_EXPR)
9692 && !TYPE_SATURATING (type)
9693 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9695 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
9700 if (! FLOAT_TYPE_P (type))
9702 if (integer_zerop (arg1))
9703 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9705 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9706 with a constant, and the two constants have no bits in common,
9707 we should treat this as a BIT_IOR_EXPR since this may produce more
9709 if (TREE_CODE (arg0) == BIT_AND_EXPR
9710 && TREE_CODE (arg1) == BIT_AND_EXPR
9711 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9712 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9713 && integer_zerop (const_binop (BIT_AND_EXPR,
9714 TREE_OPERAND (arg0, 1),
9715 TREE_OPERAND (arg1, 1))))
9717 code = BIT_IOR_EXPR;
9721 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9722 (plus (plus (mult) (mult)) (foo)) so that we can
9723 take advantage of the factoring cases below. */
9724 if (((TREE_CODE (arg0) == PLUS_EXPR
9725 || TREE_CODE (arg0) == MINUS_EXPR)
9726 && TREE_CODE (arg1) == MULT_EXPR)
9727 || ((TREE_CODE (arg1) == PLUS_EXPR
9728 || TREE_CODE (arg1) == MINUS_EXPR)
9729 && TREE_CODE (arg0) == MULT_EXPR))
9731 tree parg0, parg1, parg, marg;
9732 enum tree_code pcode;
9734 if (TREE_CODE (arg1) == MULT_EXPR)
9735 parg = arg0, marg = arg1;
9737 parg = arg1, marg = arg0;
9738 pcode = TREE_CODE (parg);
9739 parg0 = TREE_OPERAND (parg, 0);
9740 parg1 = TREE_OPERAND (parg, 1);
9744 if (TREE_CODE (parg0) == MULT_EXPR
9745 && TREE_CODE (parg1) != MULT_EXPR)
9746 return fold_build2_loc (loc, pcode, type,
9747 fold_build2_loc (loc, PLUS_EXPR, type,
9748 fold_convert_loc (loc, type,
9750 fold_convert_loc (loc, type,
9752 fold_convert_loc (loc, type, parg1));
9753 if (TREE_CODE (parg0) != MULT_EXPR
9754 && TREE_CODE (parg1) == MULT_EXPR)
9756 fold_build2_loc (loc, PLUS_EXPR, type,
9757 fold_convert_loc (loc, type, parg0),
9758 fold_build2_loc (loc, pcode, type,
9759 fold_convert_loc (loc, type, marg),
9760 fold_convert_loc (loc, type,
9766 /* See if ARG1 is zero and X + ARG1 reduces to X. */
9767 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
9768 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9770 /* Likewise if the operands are reversed. */
9771 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
9772 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9774 /* Convert X + -C into X - C. */
9775 if (TREE_CODE (arg1) == REAL_CST
9776 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
9778 tem = fold_negate_const (arg1, type);
9779 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
9780 return fold_build2_loc (loc, MINUS_EXPR, type,
9781 fold_convert_loc (loc, type, arg0),
9782 fold_convert_loc (loc, type, tem));
9785 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
9786 to __complex__ ( x, y ). This is not the same for SNaNs or
9787 if signed zeros are involved. */
9788 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
9789 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
9790 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
9792 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
9793 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
9794 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
9795 bool arg0rz = false, arg0iz = false;
9796 if ((arg0r && (arg0rz = real_zerop (arg0r)))
9797 || (arg0i && (arg0iz = real_zerop (arg0i))))
9799 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
9800 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
9801 if (arg0rz && arg1i && real_zerop (arg1i))
9803 tree rp = arg1r ? arg1r
9804 : build1 (REALPART_EXPR, rtype, arg1);
9805 tree ip = arg0i ? arg0i
9806 : build1 (IMAGPART_EXPR, rtype, arg0);
9807 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9809 else if (arg0iz && arg1r && real_zerop (arg1r))
9811 tree rp = arg0r ? arg0r
9812 : build1 (REALPART_EXPR, rtype, arg0);
9813 tree ip = arg1i ? arg1i
9814 : build1 (IMAGPART_EXPR, rtype, arg1);
9815 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9820 if (flag_unsafe_math_optimizations
9821 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
9822 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
9823 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
9826 /* Convert x+x into x*2.0. */
9827 if (operand_equal_p (arg0, arg1, 0)
9828 && SCALAR_FLOAT_TYPE_P (type))
9829 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
9830 build_real (type, dconst2));
9832 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
9833 We associate floats only if the user has specified
9834 -fassociative-math. */
9835 if (flag_associative_math
9836 && TREE_CODE (arg1) == PLUS_EXPR
9837 && TREE_CODE (arg0) != MULT_EXPR)
9839 tree tree10 = TREE_OPERAND (arg1, 0);
9840 tree tree11 = TREE_OPERAND (arg1, 1);
9841 if (TREE_CODE (tree11) == MULT_EXPR
9842 && TREE_CODE (tree10) == MULT_EXPR)
9845 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
9846 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
9849 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
9850 We associate floats only if the user has specified
9851 -fassociative-math. */
9852 if (flag_associative_math
9853 && TREE_CODE (arg0) == PLUS_EXPR
9854 && TREE_CODE (arg1) != MULT_EXPR)
9856 tree tree00 = TREE_OPERAND (arg0, 0);
9857 tree tree01 = TREE_OPERAND (arg0, 1);
9858 if (TREE_CODE (tree01) == MULT_EXPR
9859 && TREE_CODE (tree00) == MULT_EXPR)
9862 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
9863 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
9869 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
9870 is a rotate of A by C1 bits. */
9871 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
9872 is a rotate of A by B bits. */
9874 enum tree_code code0, code1;
9876 code0 = TREE_CODE (arg0);
9877 code1 = TREE_CODE (arg1);
9878 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
9879 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
9880 && operand_equal_p (TREE_OPERAND (arg0, 0),
9881 TREE_OPERAND (arg1, 0), 0)
9882 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
9883 TYPE_UNSIGNED (rtype))
9884 /* Only create rotates in complete modes. Other cases are not
9885 expanded properly. */
9886 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
9888 tree tree01, tree11;
9889 enum tree_code code01, code11;
9891 tree01 = TREE_OPERAND (arg0, 1);
9892 tree11 = TREE_OPERAND (arg1, 1);
9893 STRIP_NOPS (tree01);
9894 STRIP_NOPS (tree11);
9895 code01 = TREE_CODE (tree01);
9896 code11 = TREE_CODE (tree11);
9897 if (code01 == INTEGER_CST
9898 && code11 == INTEGER_CST
9899 && TREE_INT_CST_HIGH (tree01) == 0
9900 && TREE_INT_CST_HIGH (tree11) == 0
9901 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
9902 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
9904 tem = build2_loc (loc, LROTATE_EXPR,
9905 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9906 TREE_OPERAND (arg0, 0),
9907 code0 == LSHIFT_EXPR ? tree01 : tree11);
9908 return fold_convert_loc (loc, type, tem);
9910 else if (code11 == MINUS_EXPR)
9912 tree tree110, tree111;
9913 tree110 = TREE_OPERAND (tree11, 0);
9914 tree111 = TREE_OPERAND (tree11, 1);
9915 STRIP_NOPS (tree110);
9916 STRIP_NOPS (tree111);
9917 if (TREE_CODE (tree110) == INTEGER_CST
9918 && 0 == compare_tree_int (tree110,
9920 (TREE_TYPE (TREE_OPERAND
9922 && operand_equal_p (tree01, tree111, 0))
9924 fold_convert_loc (loc, type,
9925 build2 ((code0 == LSHIFT_EXPR
9928 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9929 TREE_OPERAND (arg0, 0), tree01));
9931 else if (code01 == MINUS_EXPR)
9933 tree tree010, tree011;
9934 tree010 = TREE_OPERAND (tree01, 0);
9935 tree011 = TREE_OPERAND (tree01, 1);
9936 STRIP_NOPS (tree010);
9937 STRIP_NOPS (tree011);
9938 if (TREE_CODE (tree010) == INTEGER_CST
9939 && 0 == compare_tree_int (tree010,
9941 (TREE_TYPE (TREE_OPERAND
9943 && operand_equal_p (tree11, tree011, 0))
9944 return fold_convert_loc
9946 build2 ((code0 != LSHIFT_EXPR
9949 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9950 TREE_OPERAND (arg0, 0), tree11));
9956 /* In most languages, can't associate operations on floats through
9957 parentheses. Rather than remember where the parentheses were, we
9958 don't associate floats at all, unless the user has specified
9960 And, we need to make sure type is not saturating. */
9962 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
9963 && !TYPE_SATURATING (type))
9965 tree var0, con0, lit0, minus_lit0;
9966 tree var1, con1, lit1, minus_lit1;
9969 /* Split both trees into variables, constants, and literals. Then
9970 associate each group together, the constants with literals,
9971 then the result with variables. This increases the chances of
9972 literals being recombined later and of generating relocatable
9973 expressions for the sum of a constant and literal. */
9974 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
9975 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
9976 code == MINUS_EXPR);
9978 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
9979 if (code == MINUS_EXPR)
9982 /* With undefined overflow we can only associate constants with one
9983 variable, and constants whose association doesn't overflow. */
9984 if ((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
9985 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
9992 if (TREE_CODE (tmp0) == NEGATE_EXPR)
9993 tmp0 = TREE_OPERAND (tmp0, 0);
9994 if (TREE_CODE (tmp1) == NEGATE_EXPR)
9995 tmp1 = TREE_OPERAND (tmp1, 0);
9996 /* The only case we can still associate with two variables
9997 is if they are the same, modulo negation. */
9998 if (!operand_equal_p (tmp0, tmp1, 0))
10002 if (ok && lit0 && lit1)
10004 tree tmp0 = fold_convert (type, lit0);
10005 tree tmp1 = fold_convert (type, lit1);
10007 if (!TREE_OVERFLOW (tmp0) && !TREE_OVERFLOW (tmp1)
10008 && TREE_OVERFLOW (fold_build2 (code, type, tmp0, tmp1)))
10013 /* Only do something if we found more than two objects. Otherwise,
10014 nothing has changed and we risk infinite recursion. */
10016 && (2 < ((var0 != 0) + (var1 != 0)
10017 + (con0 != 0) + (con1 != 0)
10018 + (lit0 != 0) + (lit1 != 0)
10019 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10021 var0 = associate_trees (loc, var0, var1, code, type);
10022 con0 = associate_trees (loc, con0, con1, code, type);
10023 lit0 = associate_trees (loc, lit0, lit1, code, type);
10024 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10026 /* Preserve the MINUS_EXPR if the negative part of the literal is
10027 greater than the positive part. Otherwise, the multiplicative
10028 folding code (i.e extract_muldiv) may be fooled in case
10029 unsigned constants are subtracted, like in the following
10030 example: ((X*2 + 4) - 8U)/2. */
10031 if (minus_lit0 && lit0)
10033 if (TREE_CODE (lit0) == INTEGER_CST
10034 && TREE_CODE (minus_lit0) == INTEGER_CST
10035 && tree_int_cst_lt (lit0, minus_lit0))
10037 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10043 lit0 = associate_trees (loc, lit0, minus_lit0,
10052 fold_convert_loc (loc, type,
10053 associate_trees (loc, var0, minus_lit0,
10054 MINUS_EXPR, type));
10057 con0 = associate_trees (loc, con0, minus_lit0,
10060 fold_convert_loc (loc, type,
10061 associate_trees (loc, var0, con0,
10066 con0 = associate_trees (loc, con0, lit0, code, type);
10068 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10076 /* Pointer simplifications for subtraction, simple reassociations. */
10077 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10079 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10080 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10081 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10083 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10084 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10085 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10086 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10087 return fold_build2_loc (loc, PLUS_EXPR, type,
10088 fold_build2_loc (loc, MINUS_EXPR, type,
10090 fold_build2_loc (loc, MINUS_EXPR, type,
10093 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10094 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10096 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10097 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10098 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10099 fold_convert_loc (loc, type, arg1));
10101 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10104 /* A - (-B) -> A + B */
10105 if (TREE_CODE (arg1) == NEGATE_EXPR)
10106 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10107 fold_convert_loc (loc, type,
10108 TREE_OPERAND (arg1, 0)));
10109 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10110 if (TREE_CODE (arg0) == NEGATE_EXPR
10111 && (FLOAT_TYPE_P (type)
10112 || INTEGRAL_TYPE_P (type))
10113 && negate_expr_p (arg1)
10114 && reorder_operands_p (arg0, arg1))
10115 return fold_build2_loc (loc, MINUS_EXPR, type,
10116 fold_convert_loc (loc, type,
10117 negate_expr (arg1)),
10118 fold_convert_loc (loc, type,
10119 TREE_OPERAND (arg0, 0)));
10120 /* Convert -A - 1 to ~A. */
10121 if (INTEGRAL_TYPE_P (type)
10122 && TREE_CODE (arg0) == NEGATE_EXPR
10123 && integer_onep (arg1)
10124 && !TYPE_OVERFLOW_TRAPS (type))
10125 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10126 fold_convert_loc (loc, type,
10127 TREE_OPERAND (arg0, 0)));
10129 /* Convert -1 - A to ~A. */
10130 if (INTEGRAL_TYPE_P (type)
10131 && integer_all_onesp (arg0))
10132 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10135 /* X - (X / CST) * CST is X % CST. */
10136 if (INTEGRAL_TYPE_P (type)
10137 && TREE_CODE (arg1) == MULT_EXPR
10138 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10139 && operand_equal_p (arg0,
10140 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10141 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10142 TREE_OPERAND (arg1, 1), 0))
10144 fold_convert_loc (loc, type,
10145 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10146 arg0, TREE_OPERAND (arg1, 1)));
10148 if (! FLOAT_TYPE_P (type))
10150 if (integer_zerop (arg0))
10151 return negate_expr (fold_convert_loc (loc, type, arg1));
10152 if (integer_zerop (arg1))
10153 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10155 /* Fold A - (A & B) into ~B & A. */
10156 if (!TREE_SIDE_EFFECTS (arg0)
10157 && TREE_CODE (arg1) == BIT_AND_EXPR)
10159 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10161 tree arg10 = fold_convert_loc (loc, type,
10162 TREE_OPERAND (arg1, 0));
10163 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10164 fold_build1_loc (loc, BIT_NOT_EXPR,
10166 fold_convert_loc (loc, type, arg0));
10168 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10170 tree arg11 = fold_convert_loc (loc,
10171 type, TREE_OPERAND (arg1, 1));
10172 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10173 fold_build1_loc (loc, BIT_NOT_EXPR,
10175 fold_convert_loc (loc, type, arg0));
10179 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10180 any power of 2 minus 1. */
10181 if (TREE_CODE (arg0) == BIT_AND_EXPR
10182 && TREE_CODE (arg1) == BIT_AND_EXPR
10183 && operand_equal_p (TREE_OPERAND (arg0, 0),
10184 TREE_OPERAND (arg1, 0), 0))
10186 tree mask0 = TREE_OPERAND (arg0, 1);
10187 tree mask1 = TREE_OPERAND (arg1, 1);
10188 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10190 if (operand_equal_p (tem, mask1, 0))
10192 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10193 TREE_OPERAND (arg0, 0), mask1);
10194 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10199 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10200 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10201 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10203 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10204 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10205 (-ARG1 + ARG0) reduces to -ARG1. */
10206 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10207 return negate_expr (fold_convert_loc (loc, type, arg1));
10209 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10210 __complex__ ( x, -y ). This is not the same for SNaNs or if
10211 signed zeros are involved. */
10212 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10213 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10214 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10216 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10217 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10218 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10219 bool arg0rz = false, arg0iz = false;
10220 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10221 || (arg0i && (arg0iz = real_zerop (arg0i))))
10223 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10224 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10225 if (arg0rz && arg1i && real_zerop (arg1i))
10227 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10229 : build1 (REALPART_EXPR, rtype, arg1));
10230 tree ip = arg0i ? arg0i
10231 : build1 (IMAGPART_EXPR, rtype, arg0);
10232 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10234 else if (arg0iz && arg1r && real_zerop (arg1r))
10236 tree rp = arg0r ? arg0r
10237 : build1 (REALPART_EXPR, rtype, arg0);
10238 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10240 : build1 (IMAGPART_EXPR, rtype, arg1));
10241 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10246 /* Fold &x - &x. This can happen from &x.foo - &x.
10247 This is unsafe for certain floats even in non-IEEE formats.
10248 In IEEE, it is unsafe because it does wrong for NaNs.
10249 Also note that operand_equal_p is always false if an operand
10252 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10253 && operand_equal_p (arg0, arg1, 0))
10254 return build_zero_cst (type);
10256 /* A - B -> A + (-B) if B is easily negatable. */
10257 if (negate_expr_p (arg1)
10258 && ((FLOAT_TYPE_P (type)
10259 /* Avoid this transformation if B is a positive REAL_CST. */
10260 && (TREE_CODE (arg1) != REAL_CST
10261 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10262 || INTEGRAL_TYPE_P (type)))
10263 return fold_build2_loc (loc, PLUS_EXPR, type,
10264 fold_convert_loc (loc, type, arg0),
10265 fold_convert_loc (loc, type,
10266 negate_expr (arg1)));
10268 /* Try folding difference of addresses. */
10270 HOST_WIDE_INT diff;
10272 if ((TREE_CODE (arg0) == ADDR_EXPR
10273 || TREE_CODE (arg1) == ADDR_EXPR)
10274 && ptr_difference_const (arg0, arg1, &diff))
10275 return build_int_cst_type (type, diff);
10278 /* Fold &a[i] - &a[j] to i-j. */
10279 if (TREE_CODE (arg0) == ADDR_EXPR
10280 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10281 && TREE_CODE (arg1) == ADDR_EXPR
10282 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10284 tree aref0 = TREE_OPERAND (arg0, 0);
10285 tree aref1 = TREE_OPERAND (arg1, 0);
10286 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10287 TREE_OPERAND (aref1, 0), 0))
10289 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
10290 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
10291 tree esz = array_ref_element_size (aref0);
10292 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10293 return fold_build2_loc (loc, MULT_EXPR, type, diff,
10294 fold_convert_loc (loc, type, esz));
10299 if (FLOAT_TYPE_P (type)
10300 && flag_unsafe_math_optimizations
10301 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10302 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10303 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10306 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10307 same or one. Make sure type is not saturating.
10308 fold_plusminus_mult_expr will re-associate. */
10309 if ((TREE_CODE (arg0) == MULT_EXPR
10310 || TREE_CODE (arg1) == MULT_EXPR)
10311 && !TYPE_SATURATING (type)
10312 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10314 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10322 /* (-A) * (-B) -> A * B */
10323 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10324 return fold_build2_loc (loc, MULT_EXPR, type,
10325 fold_convert_loc (loc, type,
10326 TREE_OPERAND (arg0, 0)),
10327 fold_convert_loc (loc, type,
10328 negate_expr (arg1)));
10329 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10330 return fold_build2_loc (loc, MULT_EXPR, type,
10331 fold_convert_loc (loc, type,
10332 negate_expr (arg0)),
10333 fold_convert_loc (loc, type,
10334 TREE_OPERAND (arg1, 0)));
10336 if (! FLOAT_TYPE_P (type))
10338 if (integer_zerop (arg1))
10339 return omit_one_operand_loc (loc, type, arg1, arg0);
10340 if (integer_onep (arg1))
10341 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10342 /* Transform x * -1 into -x. Make sure to do the negation
10343 on the original operand with conversions not stripped
10344 because we can only strip non-sign-changing conversions. */
10345 if (integer_all_onesp (arg1))
10346 return fold_convert_loc (loc, type, negate_expr (op0));
10347 /* Transform x * -C into -x * C if x is easily negatable. */
10348 if (TREE_CODE (arg1) == INTEGER_CST
10349 && tree_int_cst_sgn (arg1) == -1
10350 && negate_expr_p (arg0)
10351 && (tem = negate_expr (arg1)) != arg1
10352 && !TREE_OVERFLOW (tem))
10353 return fold_build2_loc (loc, MULT_EXPR, type,
10354 fold_convert_loc (loc, type,
10355 negate_expr (arg0)),
10358 /* (a * (1 << b)) is (a << b) */
10359 if (TREE_CODE (arg1) == LSHIFT_EXPR
10360 && integer_onep (TREE_OPERAND (arg1, 0)))
10361 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
10362 TREE_OPERAND (arg1, 1));
10363 if (TREE_CODE (arg0) == LSHIFT_EXPR
10364 && integer_onep (TREE_OPERAND (arg0, 0)))
10365 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
10366 TREE_OPERAND (arg0, 1));
10368 /* (A + A) * C -> A * 2 * C */
10369 if (TREE_CODE (arg0) == PLUS_EXPR
10370 && TREE_CODE (arg1) == INTEGER_CST
10371 && operand_equal_p (TREE_OPERAND (arg0, 0),
10372 TREE_OPERAND (arg0, 1), 0))
10373 return fold_build2_loc (loc, MULT_EXPR, type,
10374 omit_one_operand_loc (loc, type,
10375 TREE_OPERAND (arg0, 0),
10376 TREE_OPERAND (arg0, 1)),
10377 fold_build2_loc (loc, MULT_EXPR, type,
10378 build_int_cst (type, 2) , arg1));
10380 strict_overflow_p = false;
10381 if (TREE_CODE (arg1) == INTEGER_CST
10382 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10383 &strict_overflow_p)))
10385 if (strict_overflow_p)
10386 fold_overflow_warning (("assuming signed overflow does not "
10387 "occur when simplifying "
10389 WARN_STRICT_OVERFLOW_MISC);
10390 return fold_convert_loc (loc, type, tem);
10393 /* Optimize z * conj(z) for integer complex numbers. */
10394 if (TREE_CODE (arg0) == CONJ_EXPR
10395 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10396 return fold_mult_zconjz (loc, type, arg1);
10397 if (TREE_CODE (arg1) == CONJ_EXPR
10398 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10399 return fold_mult_zconjz (loc, type, arg0);
10403 /* Maybe fold x * 0 to 0. The expressions aren't the same
10404 when x is NaN, since x * 0 is also NaN. Nor are they the
10405 same in modes with signed zeros, since multiplying a
10406 negative value by 0 gives -0, not +0. */
10407 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10408 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10409 && real_zerop (arg1))
10410 return omit_one_operand_loc (loc, type, arg1, arg0);
10411 /* In IEEE floating point, x*1 is not equivalent to x for snans.
10412 Likewise for complex arithmetic with signed zeros. */
10413 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10414 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10415 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10416 && real_onep (arg1))
10417 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10419 /* Transform x * -1.0 into -x. */
10420 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10421 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10422 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10423 && real_minus_onep (arg1))
10424 return fold_convert_loc (loc, type, negate_expr (arg0));
10426 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10427 the result for floating point types due to rounding so it is applied
10428 only if -fassociative-math was specify. */
10429 if (flag_associative_math
10430 && TREE_CODE (arg0) == RDIV_EXPR
10431 && TREE_CODE (arg1) == REAL_CST
10432 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10434 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10437 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
10438 TREE_OPERAND (arg0, 1));
10441 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10442 if (operand_equal_p (arg0, arg1, 0))
10444 tree tem = fold_strip_sign_ops (arg0);
10445 if (tem != NULL_TREE)
10447 tem = fold_convert_loc (loc, type, tem);
10448 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
10452 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10453 This is not the same for NaNs or if signed zeros are
10455 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10456 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10457 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10458 && TREE_CODE (arg1) == COMPLEX_CST
10459 && real_zerop (TREE_REALPART (arg1)))
10461 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10462 if (real_onep (TREE_IMAGPART (arg1)))
10464 fold_build2_loc (loc, COMPLEX_EXPR, type,
10465 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
10467 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
10468 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10470 fold_build2_loc (loc, COMPLEX_EXPR, type,
10471 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
10472 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
10476 /* Optimize z * conj(z) for floating point complex numbers.
10477 Guarded by flag_unsafe_math_optimizations as non-finite
10478 imaginary components don't produce scalar results. */
10479 if (flag_unsafe_math_optimizations
10480 && TREE_CODE (arg0) == CONJ_EXPR
10481 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10482 return fold_mult_zconjz (loc, type, arg1);
10483 if (flag_unsafe_math_optimizations
10484 && TREE_CODE (arg1) == CONJ_EXPR
10485 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10486 return fold_mult_zconjz (loc, type, arg0);
10488 if (flag_unsafe_math_optimizations)
10490 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10491 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10493 /* Optimizations of root(...)*root(...). */
10494 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10497 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10498 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10500 /* Optimize sqrt(x)*sqrt(x) as x. */
10501 if (BUILTIN_SQRT_P (fcode0)
10502 && operand_equal_p (arg00, arg10, 0)
10503 && ! HONOR_SNANS (TYPE_MODE (type)))
10506 /* Optimize root(x)*root(y) as root(x*y). */
10507 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10508 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
10509 return build_call_expr_loc (loc, rootfn, 1, arg);
10512 /* Optimize expN(x)*expN(y) as expN(x+y). */
10513 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10515 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10516 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10517 CALL_EXPR_ARG (arg0, 0),
10518 CALL_EXPR_ARG (arg1, 0));
10519 return build_call_expr_loc (loc, expfn, 1, arg);
10522 /* Optimizations of pow(...)*pow(...). */
10523 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10524 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10525 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10527 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10528 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10529 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10530 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10532 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10533 if (operand_equal_p (arg01, arg11, 0))
10535 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10536 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
10538 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
10541 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10542 if (operand_equal_p (arg00, arg10, 0))
10544 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10545 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10547 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
10551 /* Optimize tan(x)*cos(x) as sin(x). */
10552 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10553 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10554 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10555 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10556 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10557 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10558 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10559 CALL_EXPR_ARG (arg1, 0), 0))
10561 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10563 if (sinfn != NULL_TREE)
10564 return build_call_expr_loc (loc, sinfn, 1,
10565 CALL_EXPR_ARG (arg0, 0));
10568 /* Optimize x*pow(x,c) as pow(x,c+1). */
10569 if (fcode1 == BUILT_IN_POW
10570 || fcode1 == BUILT_IN_POWF
10571 || fcode1 == BUILT_IN_POWL)
10573 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10574 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10575 if (TREE_CODE (arg11) == REAL_CST
10576 && !TREE_OVERFLOW (arg11)
10577 && operand_equal_p (arg0, arg10, 0))
10579 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10583 c = TREE_REAL_CST (arg11);
10584 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10585 arg = build_real (type, c);
10586 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10590 /* Optimize pow(x,c)*x as pow(x,c+1). */
10591 if (fcode0 == BUILT_IN_POW
10592 || fcode0 == BUILT_IN_POWF
10593 || fcode0 == BUILT_IN_POWL)
10595 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10596 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10597 if (TREE_CODE (arg01) == REAL_CST
10598 && !TREE_OVERFLOW (arg01)
10599 && operand_equal_p (arg1, arg00, 0))
10601 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10605 c = TREE_REAL_CST (arg01);
10606 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10607 arg = build_real (type, c);
10608 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
10612 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10613 if (!in_gimple_form
10614 && optimize_function_for_speed_p (cfun)
10615 && operand_equal_p (arg0, arg1, 0))
10617 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10621 tree arg = build_real (type, dconst2);
10622 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10631 if (integer_all_onesp (arg1))
10632 return omit_one_operand_loc (loc, type, arg1, arg0);
10633 if (integer_zerop (arg1))
10634 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10635 if (operand_equal_p (arg0, arg1, 0))
10636 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10638 /* ~X | X is -1. */
10639 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10640 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10642 t1 = build_zero_cst (type);
10643 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10644 return omit_one_operand_loc (loc, type, t1, arg1);
10647 /* X | ~X is -1. */
10648 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10649 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10651 t1 = build_zero_cst (type);
10652 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10653 return omit_one_operand_loc (loc, type, t1, arg0);
10656 /* Canonicalize (X & C1) | C2. */
10657 if (TREE_CODE (arg0) == BIT_AND_EXPR
10658 && TREE_CODE (arg1) == INTEGER_CST
10659 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10661 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10662 int width = TYPE_PRECISION (type), w;
10663 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10664 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10665 hi2 = TREE_INT_CST_HIGH (arg1);
10666 lo2 = TREE_INT_CST_LOW (arg1);
10668 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10669 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10670 return omit_one_operand_loc (loc, type, arg1,
10671 TREE_OPERAND (arg0, 0));
10673 if (width > HOST_BITS_PER_WIDE_INT)
10675 mhi = (unsigned HOST_WIDE_INT) -1
10676 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10682 mlo = (unsigned HOST_WIDE_INT) -1
10683 >> (HOST_BITS_PER_WIDE_INT - width);
10686 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10687 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10688 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10689 TREE_OPERAND (arg0, 0), arg1);
10691 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10692 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10693 mode which allows further optimizations. */
10700 for (w = BITS_PER_UNIT;
10701 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10704 unsigned HOST_WIDE_INT mask
10705 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10706 if (((lo1 | lo2) & mask) == mask
10707 && (lo1 & ~mask) == 0 && hi1 == 0)
10714 if (hi3 != hi1 || lo3 != lo1)
10715 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10716 fold_build2_loc (loc, BIT_AND_EXPR, type,
10717 TREE_OPERAND (arg0, 0),
10718 build_int_cst_wide (type,
10723 /* (X & Y) | Y is (X, Y). */
10724 if (TREE_CODE (arg0) == BIT_AND_EXPR
10725 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10726 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10727 /* (X & Y) | X is (Y, X). */
10728 if (TREE_CODE (arg0) == BIT_AND_EXPR
10729 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10730 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10731 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
10732 /* X | (X & Y) is (Y, X). */
10733 if (TREE_CODE (arg1) == BIT_AND_EXPR
10734 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10735 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10736 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
10737 /* X | (Y & X) is (Y, X). */
10738 if (TREE_CODE (arg1) == BIT_AND_EXPR
10739 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10740 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10741 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
10743 /* (X & ~Y) | (~X & Y) is X ^ Y */
10744 if (TREE_CODE (arg0) == BIT_AND_EXPR
10745 && TREE_CODE (arg1) == BIT_AND_EXPR)
10747 tree a0, a1, l0, l1, n0, n1;
10749 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10750 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10752 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10753 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10755 n0 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l0);
10756 n1 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l1);
10758 if ((operand_equal_p (n0, a0, 0)
10759 && operand_equal_p (n1, a1, 0))
10760 || (operand_equal_p (n0, a1, 0)
10761 && operand_equal_p (n1, a0, 0)))
10762 return fold_build2_loc (loc, BIT_XOR_EXPR, type, l0, n1);
10765 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
10766 if (t1 != NULL_TREE)
10769 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10771 This results in more efficient code for machines without a NAND
10772 instruction. Combine will canonicalize to the first form
10773 which will allow use of NAND instructions provided by the
10774 backend if they exist. */
10775 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10776 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10779 fold_build1_loc (loc, BIT_NOT_EXPR, type,
10780 build2 (BIT_AND_EXPR, type,
10781 fold_convert_loc (loc, type,
10782 TREE_OPERAND (arg0, 0)),
10783 fold_convert_loc (loc, type,
10784 TREE_OPERAND (arg1, 0))));
10787 /* See if this can be simplified into a rotate first. If that
10788 is unsuccessful continue in the association code. */
10792 if (integer_zerop (arg1))
10793 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10794 if (integer_all_onesp (arg1))
10795 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
10796 if (operand_equal_p (arg0, arg1, 0))
10797 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10799 /* ~X ^ X is -1. */
10800 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10801 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10803 t1 = build_zero_cst (type);
10804 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10805 return omit_one_operand_loc (loc, type, t1, arg1);
10808 /* X ^ ~X is -1. */
10809 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10810 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10812 t1 = build_zero_cst (type);
10813 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10814 return omit_one_operand_loc (loc, type, t1, arg0);
10817 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10818 with a constant, and the two constants have no bits in common,
10819 we should treat this as a BIT_IOR_EXPR since this may produce more
10820 simplifications. */
10821 if (TREE_CODE (arg0) == BIT_AND_EXPR
10822 && TREE_CODE (arg1) == BIT_AND_EXPR
10823 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10824 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10825 && integer_zerop (const_binop (BIT_AND_EXPR,
10826 TREE_OPERAND (arg0, 1),
10827 TREE_OPERAND (arg1, 1))))
10829 code = BIT_IOR_EXPR;
10833 /* (X | Y) ^ X -> Y & ~ X*/
10834 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10835 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10837 tree t2 = TREE_OPERAND (arg0, 1);
10838 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10840 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10841 fold_convert_loc (loc, type, t2),
10842 fold_convert_loc (loc, type, t1));
10846 /* (Y | X) ^ X -> Y & ~ X*/
10847 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10848 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10850 tree t2 = TREE_OPERAND (arg0, 0);
10851 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10853 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10854 fold_convert_loc (loc, type, t2),
10855 fold_convert_loc (loc, type, t1));
10859 /* X ^ (X | Y) -> Y & ~ X*/
10860 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10861 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
10863 tree t2 = TREE_OPERAND (arg1, 1);
10864 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10866 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10867 fold_convert_loc (loc, type, t2),
10868 fold_convert_loc (loc, type, t1));
10872 /* X ^ (Y | X) -> Y & ~ X*/
10873 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10874 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
10876 tree t2 = TREE_OPERAND (arg1, 0);
10877 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10879 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10880 fold_convert_loc (loc, type, t2),
10881 fold_convert_loc (loc, type, t1));
10885 /* Convert ~X ^ ~Y to X ^ Y. */
10886 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10887 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10888 return fold_build2_loc (loc, code, type,
10889 fold_convert_loc (loc, type,
10890 TREE_OPERAND (arg0, 0)),
10891 fold_convert_loc (loc, type,
10892 TREE_OPERAND (arg1, 0)));
10894 /* Convert ~X ^ C to X ^ ~C. */
10895 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10896 && TREE_CODE (arg1) == INTEGER_CST)
10897 return fold_build2_loc (loc, code, type,
10898 fold_convert_loc (loc, type,
10899 TREE_OPERAND (arg0, 0)),
10900 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
10902 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
10903 if (TREE_CODE (arg0) == BIT_AND_EXPR
10904 && integer_onep (TREE_OPERAND (arg0, 1))
10905 && integer_onep (arg1))
10906 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
10907 build_int_cst (TREE_TYPE (arg0), 0));
10909 /* Fold (X & Y) ^ Y as ~X & Y. */
10910 if (TREE_CODE (arg0) == BIT_AND_EXPR
10911 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10913 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10914 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10915 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10916 fold_convert_loc (loc, type, arg1));
10918 /* Fold (X & Y) ^ X as ~Y & X. */
10919 if (TREE_CODE (arg0) == BIT_AND_EXPR
10920 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10921 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10923 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10924 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10925 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10926 fold_convert_loc (loc, type, arg1));
10928 /* Fold X ^ (X & Y) as X & ~Y. */
10929 if (TREE_CODE (arg1) == BIT_AND_EXPR
10930 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10932 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10933 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10934 fold_convert_loc (loc, type, arg0),
10935 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
10937 /* Fold X ^ (Y & X) as ~Y & X. */
10938 if (TREE_CODE (arg1) == BIT_AND_EXPR
10939 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10940 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10942 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10943 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10944 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10945 fold_convert_loc (loc, type, arg0));
10948 /* See if this can be simplified into a rotate first. If that
10949 is unsuccessful continue in the association code. */
10953 if (integer_all_onesp (arg1))
10954 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10955 if (integer_zerop (arg1))
10956 return omit_one_operand_loc (loc, type, arg1, arg0);
10957 if (operand_equal_p (arg0, arg1, 0))
10958 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10960 /* ~X & X, (X == 0) & X, and !X & X are always zero. */
10961 if ((TREE_CODE (arg0) == BIT_NOT_EXPR
10962 || TREE_CODE (arg0) == TRUTH_NOT_EXPR
10963 || (TREE_CODE (arg0) == EQ_EXPR
10964 && integer_zerop (TREE_OPERAND (arg0, 1))))
10965 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10966 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
10968 /* X & ~X , X & (X == 0), and X & !X are always zero. */
10969 if ((TREE_CODE (arg1) == BIT_NOT_EXPR
10970 || TREE_CODE (arg1) == TRUTH_NOT_EXPR
10971 || (TREE_CODE (arg1) == EQ_EXPR
10972 && integer_zerop (TREE_OPERAND (arg1, 1))))
10973 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10974 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10976 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
10977 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10978 && TREE_CODE (arg1) == INTEGER_CST
10979 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10981 tree tmp1 = fold_convert_loc (loc, type, arg1);
10982 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10983 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10984 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
10985 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
10987 fold_convert_loc (loc, type,
10988 fold_build2_loc (loc, BIT_IOR_EXPR,
10989 type, tmp2, tmp3));
10992 /* (X | Y) & Y is (X, Y). */
10993 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10994 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10995 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10996 /* (X | Y) & X is (Y, X). */
10997 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10998 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10999 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11000 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11001 /* X & (X | Y) is (Y, X). */
11002 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11003 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11004 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11005 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11006 /* X & (Y | X) is (Y, X). */
11007 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11008 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11009 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11010 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11012 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11013 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11014 && integer_onep (TREE_OPERAND (arg0, 1))
11015 && integer_onep (arg1))
11017 tem = TREE_OPERAND (arg0, 0);
11018 return fold_build2_loc (loc, EQ_EXPR, type,
11019 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11020 build_int_cst (TREE_TYPE (tem), 1)),
11021 build_int_cst (TREE_TYPE (tem), 0));
11023 /* Fold ~X & 1 as (X & 1) == 0. */
11024 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11025 && integer_onep (arg1))
11027 tem = TREE_OPERAND (arg0, 0);
11028 return fold_build2_loc (loc, EQ_EXPR, type,
11029 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11030 build_int_cst (TREE_TYPE (tem), 1)),
11031 build_int_cst (TREE_TYPE (tem), 0));
11033 /* Fold !X & 1 as X == 0. */
11034 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11035 && integer_onep (arg1))
11037 tem = TREE_OPERAND (arg0, 0);
11038 return fold_build2_loc (loc, EQ_EXPR, type, tem,
11039 build_int_cst (TREE_TYPE (tem), 0));
11042 /* Fold (X ^ Y) & Y as ~X & Y. */
11043 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11044 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11046 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11047 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11048 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11049 fold_convert_loc (loc, type, arg1));
11051 /* Fold (X ^ Y) & X as ~Y & X. */
11052 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11053 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11054 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11056 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11057 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11058 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11059 fold_convert_loc (loc, type, arg1));
11061 /* Fold X & (X ^ Y) as X & ~Y. */
11062 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11063 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11065 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11066 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11067 fold_convert_loc (loc, type, arg0),
11068 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11070 /* Fold X & (Y ^ X) as ~Y & X. */
11071 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11072 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11073 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11075 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11076 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11077 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11078 fold_convert_loc (loc, type, arg0));
11081 /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
11082 ((A & N) + B) & M -> (A + B) & M
11083 Similarly if (N & M) == 0,
11084 ((A | N) + B) & M -> (A + B) & M
11085 and for - instead of + (or unary - instead of +)
11086 and/or ^ instead of |.
11087 If B is constant and (B & M) == 0, fold into A & M. */
11088 if (host_integerp (arg1, 1))
11090 unsigned HOST_WIDE_INT cst1 = tree_low_cst (arg1, 1);
11091 if (~cst1 && (cst1 & (cst1 + 1)) == 0
11092 && INTEGRAL_TYPE_P (TREE_TYPE (arg0))
11093 && (TREE_CODE (arg0) == PLUS_EXPR
11094 || TREE_CODE (arg0) == MINUS_EXPR
11095 || TREE_CODE (arg0) == NEGATE_EXPR)
11096 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
11097 || TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE))
11101 unsigned HOST_WIDE_INT cst0;
11103 /* Now we know that arg0 is (C + D) or (C - D) or
11104 -C and arg1 (M) is == (1LL << cst) - 1.
11105 Store C into PMOP[0] and D into PMOP[1]. */
11106 pmop[0] = TREE_OPERAND (arg0, 0);
11108 if (TREE_CODE (arg0) != NEGATE_EXPR)
11110 pmop[1] = TREE_OPERAND (arg0, 1);
11114 if (!host_integerp (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11115 || (tree_low_cst (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11119 for (; which >= 0; which--)
11120 switch (TREE_CODE (pmop[which]))
11125 if (TREE_CODE (TREE_OPERAND (pmop[which], 1))
11128 /* tree_low_cst not used, because we don't care about
11130 cst0 = TREE_INT_CST_LOW (TREE_OPERAND (pmop[which], 1));
11132 if (TREE_CODE (pmop[which]) == BIT_AND_EXPR)
11137 else if (cst0 != 0)
11139 /* If C or D is of the form (A & N) where
11140 (N & M) == M, or of the form (A | N) or
11141 (A ^ N) where (N & M) == 0, replace it with A. */
11142 pmop[which] = TREE_OPERAND (pmop[which], 0);
11145 /* If C or D is a N where (N & M) == 0, it can be
11146 omitted (assumed 0). */
11147 if ((TREE_CODE (arg0) == PLUS_EXPR
11148 || (TREE_CODE (arg0) == MINUS_EXPR && which == 0))
11149 && (TREE_INT_CST_LOW (pmop[which]) & cst1) == 0)
11150 pmop[which] = NULL;
11156 /* Only build anything new if we optimized one or both arguments
11158 if (pmop[0] != TREE_OPERAND (arg0, 0)
11159 || (TREE_CODE (arg0) != NEGATE_EXPR
11160 && pmop[1] != TREE_OPERAND (arg0, 1)))
11162 tree utype = TREE_TYPE (arg0);
11163 if (! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
11165 /* Perform the operations in a type that has defined
11166 overflow behavior. */
11167 utype = unsigned_type_for (TREE_TYPE (arg0));
11168 if (pmop[0] != NULL)
11169 pmop[0] = fold_convert_loc (loc, utype, pmop[0]);
11170 if (pmop[1] != NULL)
11171 pmop[1] = fold_convert_loc (loc, utype, pmop[1]);
11174 if (TREE_CODE (arg0) == NEGATE_EXPR)
11175 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[0]);
11176 else if (TREE_CODE (arg0) == PLUS_EXPR)
11178 if (pmop[0] != NULL && pmop[1] != NULL)
11179 tem = fold_build2_loc (loc, PLUS_EXPR, utype,
11181 else if (pmop[0] != NULL)
11183 else if (pmop[1] != NULL)
11186 return build_int_cst (type, 0);
11188 else if (pmop[0] == NULL)
11189 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[1]);
11191 tem = fold_build2_loc (loc, MINUS_EXPR, utype,
11193 /* TEM is now the new binary +, - or unary - replacement. */
11194 tem = fold_build2_loc (loc, BIT_AND_EXPR, utype, tem,
11195 fold_convert_loc (loc, utype, arg1));
11196 return fold_convert_loc (loc, type, tem);
11201 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11202 if (t1 != NULL_TREE)
11204 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11205 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11206 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11209 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11211 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11212 && (~TREE_INT_CST_LOW (arg1)
11213 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11215 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11218 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11220 This results in more efficient code for machines without a NOR
11221 instruction. Combine will canonicalize to the first form
11222 which will allow use of NOR instructions provided by the
11223 backend if they exist. */
11224 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11225 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11227 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11228 build2 (BIT_IOR_EXPR, type,
11229 fold_convert_loc (loc, type,
11230 TREE_OPERAND (arg0, 0)),
11231 fold_convert_loc (loc, type,
11232 TREE_OPERAND (arg1, 0))));
11235 /* If arg0 is derived from the address of an object or function, we may
11236 be able to fold this expression using the object or function's
11238 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11240 unsigned HOST_WIDE_INT modulus, residue;
11241 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11243 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11244 integer_onep (arg1));
11246 /* This works because modulus is a power of 2. If this weren't the
11247 case, we'd have to replace it by its greatest power-of-2
11248 divisor: modulus & -modulus. */
11250 return build_int_cst (type, residue & low);
11253 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11254 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11255 if the new mask might be further optimized. */
11256 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11257 || TREE_CODE (arg0) == RSHIFT_EXPR)
11258 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11259 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11260 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11261 < TYPE_PRECISION (TREE_TYPE (arg0))
11262 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11263 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11265 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11266 unsigned HOST_WIDE_INT mask
11267 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11268 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11269 tree shift_type = TREE_TYPE (arg0);
11271 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11272 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11273 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11274 && TYPE_PRECISION (TREE_TYPE (arg0))
11275 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11277 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11278 tree arg00 = TREE_OPERAND (arg0, 0);
11279 /* See if more bits can be proven as zero because of
11281 if (TREE_CODE (arg00) == NOP_EXPR
11282 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11284 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11285 if (TYPE_PRECISION (inner_type)
11286 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11287 && TYPE_PRECISION (inner_type) < prec)
11289 prec = TYPE_PRECISION (inner_type);
11290 /* See if we can shorten the right shift. */
11292 shift_type = inner_type;
11295 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11296 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11297 zerobits <<= prec - shiftc;
11298 /* For arithmetic shift if sign bit could be set, zerobits
11299 can contain actually sign bits, so no transformation is
11300 possible, unless MASK masks them all away. In that
11301 case the shift needs to be converted into logical shift. */
11302 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11303 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11305 if ((mask & zerobits) == 0)
11306 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11312 /* ((X << 16) & 0xff00) is (X, 0). */
11313 if ((mask & zerobits) == mask)
11314 return omit_one_operand_loc (loc, type,
11315 build_int_cst (type, 0), arg0);
11317 newmask = mask | zerobits;
11318 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11322 /* Only do the transformation if NEWMASK is some integer
11324 for (prec = BITS_PER_UNIT;
11325 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11326 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11328 if (prec < HOST_BITS_PER_WIDE_INT
11329 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11333 if (shift_type != TREE_TYPE (arg0))
11335 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11336 fold_convert_loc (loc, shift_type,
11337 TREE_OPERAND (arg0, 0)),
11338 TREE_OPERAND (arg0, 1));
11339 tem = fold_convert_loc (loc, type, tem);
11343 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11344 if (!tree_int_cst_equal (newmaskt, arg1))
11345 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11353 /* Don't touch a floating-point divide by zero unless the mode
11354 of the constant can represent infinity. */
11355 if (TREE_CODE (arg1) == REAL_CST
11356 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11357 && real_zerop (arg1))
11360 /* Optimize A / A to 1.0 if we don't care about
11361 NaNs or Infinities. Skip the transformation
11362 for non-real operands. */
11363 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11364 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11365 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11366 && operand_equal_p (arg0, arg1, 0))
11368 tree r = build_real (TREE_TYPE (arg0), dconst1);
11370 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11373 /* The complex version of the above A / A optimization. */
11374 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11375 && operand_equal_p (arg0, arg1, 0))
11377 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11378 if (! HONOR_NANS (TYPE_MODE (elem_type))
11379 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11381 tree r = build_real (elem_type, dconst1);
11382 /* omit_two_operands will call fold_convert for us. */
11383 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11387 /* (-A) / (-B) -> A / B */
11388 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11389 return fold_build2_loc (loc, RDIV_EXPR, type,
11390 TREE_OPERAND (arg0, 0),
11391 negate_expr (arg1));
11392 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11393 return fold_build2_loc (loc, RDIV_EXPR, type,
11394 negate_expr (arg0),
11395 TREE_OPERAND (arg1, 0));
11397 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11398 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11399 && real_onep (arg1))
11400 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11402 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11403 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11404 && real_minus_onep (arg1))
11405 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11406 negate_expr (arg0)));
11408 /* If ARG1 is a constant, we can convert this to a multiply by the
11409 reciprocal. This does not have the same rounding properties,
11410 so only do this if -freciprocal-math. We can actually
11411 always safely do it if ARG1 is a power of two, but it's hard to
11412 tell if it is or not in a portable manner. */
11413 if (TREE_CODE (arg1) == REAL_CST)
11415 if (flag_reciprocal_math
11416 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11418 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11419 /* Find the reciprocal if optimizing and the result is exact. */
11423 r = TREE_REAL_CST (arg1);
11424 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11426 tem = build_real (type, r);
11427 return fold_build2_loc (loc, MULT_EXPR, type,
11428 fold_convert_loc (loc, type, arg0), tem);
11432 /* Convert A/B/C to A/(B*C). */
11433 if (flag_reciprocal_math
11434 && TREE_CODE (arg0) == RDIV_EXPR)
11435 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11436 fold_build2_loc (loc, MULT_EXPR, type,
11437 TREE_OPERAND (arg0, 1), arg1));
11439 /* Convert A/(B/C) to (A/B)*C. */
11440 if (flag_reciprocal_math
11441 && TREE_CODE (arg1) == RDIV_EXPR)
11442 return fold_build2_loc (loc, MULT_EXPR, type,
11443 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11444 TREE_OPERAND (arg1, 0)),
11445 TREE_OPERAND (arg1, 1));
11447 /* Convert C1/(X*C2) into (C1/C2)/X. */
11448 if (flag_reciprocal_math
11449 && TREE_CODE (arg1) == MULT_EXPR
11450 && TREE_CODE (arg0) == REAL_CST
11451 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11453 tree tem = const_binop (RDIV_EXPR, arg0,
11454 TREE_OPERAND (arg1, 1));
11456 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11457 TREE_OPERAND (arg1, 0));
11460 if (flag_unsafe_math_optimizations)
11462 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11463 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11465 /* Optimize sin(x)/cos(x) as tan(x). */
11466 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11467 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11468 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11469 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11470 CALL_EXPR_ARG (arg1, 0), 0))
11472 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11474 if (tanfn != NULL_TREE)
11475 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11478 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11479 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11480 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11481 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11482 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11483 CALL_EXPR_ARG (arg1, 0), 0))
11485 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11487 if (tanfn != NULL_TREE)
11489 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11490 CALL_EXPR_ARG (arg0, 0));
11491 return fold_build2_loc (loc, RDIV_EXPR, type,
11492 build_real (type, dconst1), tmp);
11496 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11497 NaNs or Infinities. */
11498 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11499 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11500 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11502 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11503 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11505 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11506 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11507 && operand_equal_p (arg00, arg01, 0))
11509 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11511 if (cosfn != NULL_TREE)
11512 return build_call_expr_loc (loc, cosfn, 1, arg00);
11516 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11517 NaNs or Infinities. */
11518 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11519 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11520 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11522 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11523 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11525 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11526 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11527 && operand_equal_p (arg00, arg01, 0))
11529 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11531 if (cosfn != NULL_TREE)
11533 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11534 return fold_build2_loc (loc, RDIV_EXPR, type,
11535 build_real (type, dconst1),
11541 /* Optimize pow(x,c)/x as pow(x,c-1). */
11542 if (fcode0 == BUILT_IN_POW
11543 || fcode0 == BUILT_IN_POWF
11544 || fcode0 == BUILT_IN_POWL)
11546 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11547 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11548 if (TREE_CODE (arg01) == REAL_CST
11549 && !TREE_OVERFLOW (arg01)
11550 && operand_equal_p (arg1, arg00, 0))
11552 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11556 c = TREE_REAL_CST (arg01);
11557 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11558 arg = build_real (type, c);
11559 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11563 /* Optimize a/root(b/c) into a*root(c/b). */
11564 if (BUILTIN_ROOT_P (fcode1))
11566 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11568 if (TREE_CODE (rootarg) == RDIV_EXPR)
11570 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11571 tree b = TREE_OPERAND (rootarg, 0);
11572 tree c = TREE_OPERAND (rootarg, 1);
11574 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
11576 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
11577 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
11581 /* Optimize x/expN(y) into x*expN(-y). */
11582 if (BUILTIN_EXPONENT_P (fcode1))
11584 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11585 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11586 arg1 = build_call_expr_loc (loc,
11588 fold_convert_loc (loc, type, arg));
11589 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11592 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11593 if (fcode1 == BUILT_IN_POW
11594 || fcode1 == BUILT_IN_POWF
11595 || fcode1 == BUILT_IN_POWL)
11597 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11598 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11599 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11600 tree neg11 = fold_convert_loc (loc, type,
11601 negate_expr (arg11));
11602 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
11603 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11608 case TRUNC_DIV_EXPR:
11609 /* Optimize (X & (-A)) / A where A is a power of 2,
11611 if (TREE_CODE (arg0) == BIT_AND_EXPR
11612 && !TYPE_UNSIGNED (type) && TREE_CODE (arg1) == INTEGER_CST
11613 && integer_pow2p (arg1) && tree_int_cst_sgn (arg1) > 0)
11615 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (arg1),
11616 arg1, TREE_OPERAND (arg0, 1));
11617 if (sum && integer_zerop (sum)) {
11618 unsigned long pow2;
11620 if (TREE_INT_CST_LOW (arg1))
11621 pow2 = exact_log2 (TREE_INT_CST_LOW (arg1));
11623 pow2 = exact_log2 (TREE_INT_CST_HIGH (arg1))
11624 + HOST_BITS_PER_WIDE_INT;
11626 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11627 TREE_OPERAND (arg0, 0),
11628 build_int_cst (integer_type_node, pow2));
11634 case FLOOR_DIV_EXPR:
11635 /* Simplify A / (B << N) where A and B are positive and B is
11636 a power of 2, to A >> (N + log2(B)). */
11637 strict_overflow_p = false;
11638 if (TREE_CODE (arg1) == LSHIFT_EXPR
11639 && (TYPE_UNSIGNED (type)
11640 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11642 tree sval = TREE_OPERAND (arg1, 0);
11643 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11645 tree sh_cnt = TREE_OPERAND (arg1, 1);
11646 unsigned long pow2;
11648 if (TREE_INT_CST_LOW (sval))
11649 pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11651 pow2 = exact_log2 (TREE_INT_CST_HIGH (sval))
11652 + HOST_BITS_PER_WIDE_INT;
11654 if (strict_overflow_p)
11655 fold_overflow_warning (("assuming signed overflow does not "
11656 "occur when simplifying A / (B << N)"),
11657 WARN_STRICT_OVERFLOW_MISC);
11659 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
11661 build_int_cst (TREE_TYPE (sh_cnt),
11663 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11664 fold_convert_loc (loc, type, arg0), sh_cnt);
11668 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11669 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11670 if (INTEGRAL_TYPE_P (type)
11671 && TYPE_UNSIGNED (type)
11672 && code == FLOOR_DIV_EXPR)
11673 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
11677 case ROUND_DIV_EXPR:
11678 case CEIL_DIV_EXPR:
11679 case EXACT_DIV_EXPR:
11680 if (integer_onep (arg1))
11681 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11682 if (integer_zerop (arg1))
11684 /* X / -1 is -X. */
11685 if (!TYPE_UNSIGNED (type)
11686 && TREE_CODE (arg1) == INTEGER_CST
11687 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11688 && TREE_INT_CST_HIGH (arg1) == -1)
11689 return fold_convert_loc (loc, type, negate_expr (arg0));
11691 /* Convert -A / -B to A / B when the type is signed and overflow is
11693 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11694 && TREE_CODE (arg0) == NEGATE_EXPR
11695 && negate_expr_p (arg1))
11697 if (INTEGRAL_TYPE_P (type))
11698 fold_overflow_warning (("assuming signed overflow does not occur "
11699 "when distributing negation across "
11701 WARN_STRICT_OVERFLOW_MISC);
11702 return fold_build2_loc (loc, code, type,
11703 fold_convert_loc (loc, type,
11704 TREE_OPERAND (arg0, 0)),
11705 fold_convert_loc (loc, type,
11706 negate_expr (arg1)));
11708 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11709 && TREE_CODE (arg1) == NEGATE_EXPR
11710 && negate_expr_p (arg0))
11712 if (INTEGRAL_TYPE_P (type))
11713 fold_overflow_warning (("assuming signed overflow does not occur "
11714 "when distributing negation across "
11716 WARN_STRICT_OVERFLOW_MISC);
11717 return fold_build2_loc (loc, code, type,
11718 fold_convert_loc (loc, type,
11719 negate_expr (arg0)),
11720 fold_convert_loc (loc, type,
11721 TREE_OPERAND (arg1, 0)));
11724 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11725 operation, EXACT_DIV_EXPR.
11727 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11728 At one time others generated faster code, it's not clear if they do
11729 after the last round to changes to the DIV code in expmed.c. */
11730 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11731 && multiple_of_p (type, arg0, arg1))
11732 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
11734 strict_overflow_p = false;
11735 if (TREE_CODE (arg1) == INTEGER_CST
11736 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11737 &strict_overflow_p)))
11739 if (strict_overflow_p)
11740 fold_overflow_warning (("assuming signed overflow does not occur "
11741 "when simplifying division"),
11742 WARN_STRICT_OVERFLOW_MISC);
11743 return fold_convert_loc (loc, type, tem);
11748 case CEIL_MOD_EXPR:
11749 case FLOOR_MOD_EXPR:
11750 case ROUND_MOD_EXPR:
11751 case TRUNC_MOD_EXPR:
11752 /* X % 1 is always zero, but be sure to preserve any side
11754 if (integer_onep (arg1))
11755 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11757 /* X % 0, return X % 0 unchanged so that we can get the
11758 proper warnings and errors. */
11759 if (integer_zerop (arg1))
11762 /* 0 % X is always zero, but be sure to preserve any side
11763 effects in X. Place this after checking for X == 0. */
11764 if (integer_zerop (arg0))
11765 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11767 /* X % -1 is zero. */
11768 if (!TYPE_UNSIGNED (type)
11769 && TREE_CODE (arg1) == INTEGER_CST
11770 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11771 && TREE_INT_CST_HIGH (arg1) == -1)
11772 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11774 /* X % -C is the same as X % C. */
11775 if (code == TRUNC_MOD_EXPR
11776 && !TYPE_UNSIGNED (type)
11777 && TREE_CODE (arg1) == INTEGER_CST
11778 && !TREE_OVERFLOW (arg1)
11779 && TREE_INT_CST_HIGH (arg1) < 0
11780 && !TYPE_OVERFLOW_TRAPS (type)
11781 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11782 && !sign_bit_p (arg1, arg1))
11783 return fold_build2_loc (loc, code, type,
11784 fold_convert_loc (loc, type, arg0),
11785 fold_convert_loc (loc, type,
11786 negate_expr (arg1)));
11788 /* X % -Y is the same as X % Y. */
11789 if (code == TRUNC_MOD_EXPR
11790 && !TYPE_UNSIGNED (type)
11791 && TREE_CODE (arg1) == NEGATE_EXPR
11792 && !TYPE_OVERFLOW_TRAPS (type))
11793 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
11794 fold_convert_loc (loc, type,
11795 TREE_OPERAND (arg1, 0)));
11797 strict_overflow_p = false;
11798 if (TREE_CODE (arg1) == INTEGER_CST
11799 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11800 &strict_overflow_p)))
11802 if (strict_overflow_p)
11803 fold_overflow_warning (("assuming signed overflow does not occur "
11804 "when simplifying modulus"),
11805 WARN_STRICT_OVERFLOW_MISC);
11806 return fold_convert_loc (loc, type, tem);
11809 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11810 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11811 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11812 && (TYPE_UNSIGNED (type)
11813 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11816 /* Also optimize A % (C << N) where C is a power of 2,
11817 to A & ((C << N) - 1). */
11818 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11819 c = TREE_OPERAND (arg1, 0);
11821 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11824 = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
11825 build_int_cst (TREE_TYPE (arg1), 1));
11826 if (strict_overflow_p)
11827 fold_overflow_warning (("assuming signed overflow does not "
11828 "occur when simplifying "
11829 "X % (power of two)"),
11830 WARN_STRICT_OVERFLOW_MISC);
11831 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11832 fold_convert_loc (loc, type, arg0),
11833 fold_convert_loc (loc, type, mask));
11841 if (integer_all_onesp (arg0))
11842 return omit_one_operand_loc (loc, type, arg0, arg1);
11846 /* Optimize -1 >> x for arithmetic right shifts. */
11847 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11848 && tree_expr_nonnegative_p (arg1))
11849 return omit_one_operand_loc (loc, type, arg0, arg1);
11850 /* ... fall through ... */
11854 if (integer_zerop (arg1))
11855 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11856 if (integer_zerop (arg0))
11857 return omit_one_operand_loc (loc, type, arg0, arg1);
11859 /* Since negative shift count is not well-defined,
11860 don't try to compute it in the compiler. */
11861 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11864 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11865 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11866 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11867 && host_integerp (TREE_OPERAND (arg0, 1), false)
11868 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11870 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11871 + TREE_INT_CST_LOW (arg1));
11873 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11874 being well defined. */
11875 if (low >= TYPE_PRECISION (type))
11877 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11878 low = low % TYPE_PRECISION (type);
11879 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11880 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
11881 TREE_OPERAND (arg0, 0));
11883 low = TYPE_PRECISION (type) - 1;
11886 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
11887 build_int_cst (type, low));
11890 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11891 into x & ((unsigned)-1 >> c) for unsigned types. */
11892 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11893 || (TYPE_UNSIGNED (type)
11894 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11895 && host_integerp (arg1, false)
11896 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11897 && host_integerp (TREE_OPERAND (arg0, 1), false)
11898 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11900 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11901 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11907 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11909 lshift = build_int_cst (type, -1);
11910 lshift = int_const_binop (code, lshift, arg1);
11912 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
11916 /* Rewrite an LROTATE_EXPR by a constant into an
11917 RROTATE_EXPR by a new constant. */
11918 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11920 tree tem = build_int_cst (TREE_TYPE (arg1),
11921 TYPE_PRECISION (type));
11922 tem = const_binop (MINUS_EXPR, tem, arg1);
11923 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
11926 /* If we have a rotate of a bit operation with the rotate count and
11927 the second operand of the bit operation both constant,
11928 permute the two operations. */
11929 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11930 && (TREE_CODE (arg0) == BIT_AND_EXPR
11931 || TREE_CODE (arg0) == BIT_IOR_EXPR
11932 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11933 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11934 return fold_build2_loc (loc, TREE_CODE (arg0), type,
11935 fold_build2_loc (loc, code, type,
11936 TREE_OPERAND (arg0, 0), arg1),
11937 fold_build2_loc (loc, code, type,
11938 TREE_OPERAND (arg0, 1), arg1));
11940 /* Two consecutive rotates adding up to the precision of the
11941 type can be ignored. */
11942 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11943 && TREE_CODE (arg0) == RROTATE_EXPR
11944 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11945 && TREE_INT_CST_HIGH (arg1) == 0
11946 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11947 && ((TREE_INT_CST_LOW (arg1)
11948 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11949 == (unsigned int) TYPE_PRECISION (type)))
11950 return TREE_OPERAND (arg0, 0);
11952 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11953 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11954 if the latter can be further optimized. */
11955 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11956 && TREE_CODE (arg0) == BIT_AND_EXPR
11957 && TREE_CODE (arg1) == INTEGER_CST
11958 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11960 tree mask = fold_build2_loc (loc, code, type,
11961 fold_convert_loc (loc, type,
11962 TREE_OPERAND (arg0, 1)),
11964 tree shift = fold_build2_loc (loc, code, type,
11965 fold_convert_loc (loc, type,
11966 TREE_OPERAND (arg0, 0)),
11968 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
11976 if (operand_equal_p (arg0, arg1, 0))
11977 return omit_one_operand_loc (loc, type, arg0, arg1);
11978 if (INTEGRAL_TYPE_P (type)
11979 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11980 return omit_one_operand_loc (loc, type, arg1, arg0);
11981 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
11987 if (operand_equal_p (arg0, arg1, 0))
11988 return omit_one_operand_loc (loc, type, arg0, arg1);
11989 if (INTEGRAL_TYPE_P (type)
11990 && TYPE_MAX_VALUE (type)
11991 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11992 return omit_one_operand_loc (loc, type, arg1, arg0);
11993 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
11998 case TRUTH_ANDIF_EXPR:
11999 /* Note that the operands of this must be ints
12000 and their values must be 0 or 1.
12001 ("true" is a fixed value perhaps depending on the language.) */
12002 /* If first arg is constant zero, return it. */
12003 if (integer_zerop (arg0))
12004 return fold_convert_loc (loc, type, arg0);
12005 case TRUTH_AND_EXPR:
12006 /* If either arg is constant true, drop it. */
12007 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12008 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12009 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
12010 /* Preserve sequence points. */
12011 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12012 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12013 /* If second arg is constant zero, result is zero, but first arg
12014 must be evaluated. */
12015 if (integer_zerop (arg1))
12016 return omit_one_operand_loc (loc, type, arg1, arg0);
12017 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
12018 case will be handled here. */
12019 if (integer_zerop (arg0))
12020 return omit_one_operand_loc (loc, type, arg0, arg1);
12022 /* !X && X is always false. */
12023 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12024 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12025 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12026 /* X && !X is always false. */
12027 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12028 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12029 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12031 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12032 means A >= Y && A != MAX, but in this case we know that
12035 if (!TREE_SIDE_EFFECTS (arg0)
12036 && !TREE_SIDE_EFFECTS (arg1))
12038 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
12039 if (tem && !operand_equal_p (tem, arg0, 0))
12040 return fold_build2_loc (loc, code, type, tem, arg1);
12042 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12043 if (tem && !operand_equal_p (tem, arg1, 0))
12044 return fold_build2_loc (loc, code, type, arg0, tem);
12047 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12053 case TRUTH_ORIF_EXPR:
12054 /* Note that the operands of this must be ints
12055 and their values must be 0 or true.
12056 ("true" is a fixed value perhaps depending on the language.) */
12057 /* If first arg is constant true, return it. */
12058 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12059 return fold_convert_loc (loc, type, arg0);
12060 case TRUTH_OR_EXPR:
12061 /* If either arg is constant zero, drop it. */
12062 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12063 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12064 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12065 /* Preserve sequence points. */
12066 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12067 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12068 /* If second arg is constant true, result is true, but we must
12069 evaluate first arg. */
12070 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12071 return omit_one_operand_loc (loc, type, arg1, arg0);
12072 /* Likewise for first arg, but note this only occurs here for
12074 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12075 return omit_one_operand_loc (loc, type, arg0, arg1);
12077 /* !X || X is always true. */
12078 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12079 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12080 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12081 /* X || !X is always true. */
12082 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12083 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12084 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12086 /* (X && !Y) || (!X && Y) is X ^ Y */
12087 if (TREE_CODE (arg0) == TRUTH_AND_EXPR
12088 && TREE_CODE (arg1) == TRUTH_AND_EXPR)
12090 tree a0, a1, l0, l1, n0, n1;
12092 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
12093 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
12095 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12096 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
12098 n0 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l0);
12099 n1 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l1);
12101 if ((operand_equal_p (n0, a0, 0)
12102 && operand_equal_p (n1, a1, 0))
12103 || (operand_equal_p (n0, a1, 0)
12104 && operand_equal_p (n1, a0, 0)))
12105 return fold_build2_loc (loc, TRUTH_XOR_EXPR, type, l0, n1);
12108 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12114 case TRUTH_XOR_EXPR:
12115 /* If the second arg is constant zero, drop it. */
12116 if (integer_zerop (arg1))
12117 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12118 /* If the second arg is constant true, this is a logical inversion. */
12119 if (integer_onep (arg1))
12121 /* Only call invert_truthvalue if operand is a truth value. */
12122 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12123 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12125 tem = invert_truthvalue_loc (loc, arg0);
12126 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12128 /* Identical arguments cancel to zero. */
12129 if (operand_equal_p (arg0, arg1, 0))
12130 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12132 /* !X ^ X is always true. */
12133 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12134 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12135 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12137 /* X ^ !X is always true. */
12138 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12139 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12140 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12149 tem = fold_comparison (loc, code, type, op0, op1);
12150 if (tem != NULL_TREE)
12153 /* bool_var != 0 becomes bool_var. */
12154 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12155 && code == NE_EXPR)
12156 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12158 /* bool_var == 1 becomes bool_var. */
12159 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12160 && code == EQ_EXPR)
12161 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12163 /* bool_var != 1 becomes !bool_var. */
12164 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12165 && code == NE_EXPR)
12166 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12167 fold_convert_loc (loc, type, arg0));
12169 /* bool_var == 0 becomes !bool_var. */
12170 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12171 && code == EQ_EXPR)
12172 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12173 fold_convert_loc (loc, type, arg0));
12175 /* !exp != 0 becomes !exp */
12176 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12177 && code == NE_EXPR)
12178 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12180 /* If this is an equality comparison of the address of two non-weak,
12181 unaliased symbols neither of which are extern (since we do not
12182 have access to attributes for externs), then we know the result. */
12183 if (TREE_CODE (arg0) == ADDR_EXPR
12184 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12185 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12186 && ! lookup_attribute ("alias",
12187 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12188 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12189 && TREE_CODE (arg1) == ADDR_EXPR
12190 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12191 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12192 && ! lookup_attribute ("alias",
12193 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12194 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12196 /* We know that we're looking at the address of two
12197 non-weak, unaliased, static _DECL nodes.
12199 It is both wasteful and incorrect to call operand_equal_p
12200 to compare the two ADDR_EXPR nodes. It is wasteful in that
12201 all we need to do is test pointer equality for the arguments
12202 to the two ADDR_EXPR nodes. It is incorrect to use
12203 operand_equal_p as that function is NOT equivalent to a
12204 C equality test. It can in fact return false for two
12205 objects which would test as equal using the C equality
12207 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12208 return constant_boolean_node (equal
12209 ? code == EQ_EXPR : code != EQ_EXPR,
12213 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12214 a MINUS_EXPR of a constant, we can convert it into a comparison with
12215 a revised constant as long as no overflow occurs. */
12216 if (TREE_CODE (arg1) == INTEGER_CST
12217 && (TREE_CODE (arg0) == PLUS_EXPR
12218 || TREE_CODE (arg0) == MINUS_EXPR)
12219 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12220 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12221 ? MINUS_EXPR : PLUS_EXPR,
12222 fold_convert_loc (loc, TREE_TYPE (arg0),
12224 TREE_OPERAND (arg0, 1)))
12225 && !TREE_OVERFLOW (tem))
12226 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12228 /* Similarly for a NEGATE_EXPR. */
12229 if (TREE_CODE (arg0) == NEGATE_EXPR
12230 && TREE_CODE (arg1) == INTEGER_CST
12231 && 0 != (tem = negate_expr (fold_convert_loc (loc, TREE_TYPE (arg0),
12233 && TREE_CODE (tem) == INTEGER_CST
12234 && !TREE_OVERFLOW (tem))
12235 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12237 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12238 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12239 && TREE_CODE (arg1) == INTEGER_CST
12240 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12241 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12242 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12243 fold_convert_loc (loc,
12246 TREE_OPERAND (arg0, 1)));
12248 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12249 if ((TREE_CODE (arg0) == PLUS_EXPR
12250 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12251 || TREE_CODE (arg0) == MINUS_EXPR)
12252 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12255 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12256 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12258 tree val = TREE_OPERAND (arg0, 1);
12259 return omit_two_operands_loc (loc, type,
12260 fold_build2_loc (loc, code, type,
12262 build_int_cst (TREE_TYPE (val),
12264 TREE_OPERAND (arg0, 0), arg1);
12267 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12268 if (TREE_CODE (arg0) == MINUS_EXPR
12269 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12270 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12273 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12275 return omit_two_operands_loc (loc, type,
12277 ? boolean_true_node : boolean_false_node,
12278 TREE_OPERAND (arg0, 1), arg1);
12281 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12282 for !=. Don't do this for ordered comparisons due to overflow. */
12283 if (TREE_CODE (arg0) == MINUS_EXPR
12284 && integer_zerop (arg1))
12285 return fold_build2_loc (loc, code, type,
12286 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12288 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12289 if (TREE_CODE (arg0) == ABS_EXPR
12290 && (integer_zerop (arg1) || real_zerop (arg1)))
12291 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12293 /* If this is an EQ or NE comparison with zero and ARG0 is
12294 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12295 two operations, but the latter can be done in one less insn
12296 on machines that have only two-operand insns or on which a
12297 constant cannot be the first operand. */
12298 if (TREE_CODE (arg0) == BIT_AND_EXPR
12299 && integer_zerop (arg1))
12301 tree arg00 = TREE_OPERAND (arg0, 0);
12302 tree arg01 = TREE_OPERAND (arg0, 1);
12303 if (TREE_CODE (arg00) == LSHIFT_EXPR
12304 && integer_onep (TREE_OPERAND (arg00, 0)))
12306 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12307 arg01, TREE_OPERAND (arg00, 1));
12308 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12309 build_int_cst (TREE_TYPE (arg0), 1));
12310 return fold_build2_loc (loc, code, type,
12311 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12314 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12315 && integer_onep (TREE_OPERAND (arg01, 0)))
12317 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12318 arg00, TREE_OPERAND (arg01, 1));
12319 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12320 build_int_cst (TREE_TYPE (arg0), 1));
12321 return fold_build2_loc (loc, code, type,
12322 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12327 /* If this is an NE or EQ comparison of zero against the result of a
12328 signed MOD operation whose second operand is a power of 2, make
12329 the MOD operation unsigned since it is simpler and equivalent. */
12330 if (integer_zerop (arg1)
12331 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12332 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12333 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12334 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12335 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12336 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12338 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12339 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12340 fold_convert_loc (loc, newtype,
12341 TREE_OPERAND (arg0, 0)),
12342 fold_convert_loc (loc, newtype,
12343 TREE_OPERAND (arg0, 1)));
12345 return fold_build2_loc (loc, code, type, newmod,
12346 fold_convert_loc (loc, newtype, arg1));
12349 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12350 C1 is a valid shift constant, and C2 is a power of two, i.e.
12352 if (TREE_CODE (arg0) == BIT_AND_EXPR
12353 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12354 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12356 && integer_pow2p (TREE_OPERAND (arg0, 1))
12357 && integer_zerop (arg1))
12359 tree itype = TREE_TYPE (arg0);
12360 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12361 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12363 /* Check for a valid shift count. */
12364 if (TREE_INT_CST_HIGH (arg001) == 0
12365 && TREE_INT_CST_LOW (arg001) < prec)
12367 tree arg01 = TREE_OPERAND (arg0, 1);
12368 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12369 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12370 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12371 can be rewritten as (X & (C2 << C1)) != 0. */
12372 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12374 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12375 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12376 return fold_build2_loc (loc, code, type, tem,
12377 fold_convert_loc (loc, itype, arg1));
12379 /* Otherwise, for signed (arithmetic) shifts,
12380 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12381 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12382 else if (!TYPE_UNSIGNED (itype))
12383 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12384 arg000, build_int_cst (itype, 0));
12385 /* Otherwise, of unsigned (logical) shifts,
12386 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12387 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12389 return omit_one_operand_loc (loc, type,
12390 code == EQ_EXPR ? integer_one_node
12391 : integer_zero_node,
12396 /* If we have (A & C) == C where C is a power of 2, convert this into
12397 (A & C) != 0. Similarly for NE_EXPR. */
12398 if (TREE_CODE (arg0) == BIT_AND_EXPR
12399 && integer_pow2p (TREE_OPERAND (arg0, 1))
12400 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12401 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12402 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12403 integer_zero_node));
12405 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12406 bit, then fold the expression into A < 0 or A >= 0. */
12407 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12411 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12412 Similarly for NE_EXPR. */
12413 if (TREE_CODE (arg0) == BIT_AND_EXPR
12414 && TREE_CODE (arg1) == INTEGER_CST
12415 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12417 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12418 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12419 TREE_OPERAND (arg0, 1));
12421 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12422 fold_convert_loc (loc, TREE_TYPE (arg0), arg1),
12424 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12425 if (integer_nonzerop (dandnotc))
12426 return omit_one_operand_loc (loc, type, rslt, arg0);
12429 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12430 Similarly for NE_EXPR. */
12431 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12432 && TREE_CODE (arg1) == INTEGER_CST
12433 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12435 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12437 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12438 TREE_OPERAND (arg0, 1),
12439 fold_convert_loc (loc, TREE_TYPE (arg0), notd));
12440 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12441 if (integer_nonzerop (candnotd))
12442 return omit_one_operand_loc (loc, type, rslt, arg0);
12445 /* If this is a comparison of a field, we may be able to simplify it. */
12446 if ((TREE_CODE (arg0) == COMPONENT_REF
12447 || TREE_CODE (arg0) == BIT_FIELD_REF)
12448 /* Handle the constant case even without -O
12449 to make sure the warnings are given. */
12450 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12452 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12457 /* Optimize comparisons of strlen vs zero to a compare of the
12458 first character of the string vs zero. To wit,
12459 strlen(ptr) == 0 => *ptr == 0
12460 strlen(ptr) != 0 => *ptr != 0
12461 Other cases should reduce to one of these two (or a constant)
12462 due to the return value of strlen being unsigned. */
12463 if (TREE_CODE (arg0) == CALL_EXPR
12464 && integer_zerop (arg1))
12466 tree fndecl = get_callee_fndecl (arg0);
12469 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12470 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12471 && call_expr_nargs (arg0) == 1
12472 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12474 tree iref = build_fold_indirect_ref_loc (loc,
12475 CALL_EXPR_ARG (arg0, 0));
12476 return fold_build2_loc (loc, code, type, iref,
12477 build_int_cst (TREE_TYPE (iref), 0));
12481 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12482 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12483 if (TREE_CODE (arg0) == RSHIFT_EXPR
12484 && integer_zerop (arg1)
12485 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12487 tree arg00 = TREE_OPERAND (arg0, 0);
12488 tree arg01 = TREE_OPERAND (arg0, 1);
12489 tree itype = TREE_TYPE (arg00);
12490 if (TREE_INT_CST_HIGH (arg01) == 0
12491 && TREE_INT_CST_LOW (arg01)
12492 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12494 if (TYPE_UNSIGNED (itype))
12496 itype = signed_type_for (itype);
12497 arg00 = fold_convert_loc (loc, itype, arg00);
12499 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12500 type, arg00, build_int_cst (itype, 0));
12504 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12505 if (integer_zerop (arg1)
12506 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12507 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12508 TREE_OPERAND (arg0, 1));
12510 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12511 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12512 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12513 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12514 build_int_cst (TREE_TYPE (arg0), 0));
12515 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12516 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12517 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12518 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12519 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12520 build_int_cst (TREE_TYPE (arg0), 0));
12522 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12523 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12524 && TREE_CODE (arg1) == INTEGER_CST
12525 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12526 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12527 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12528 TREE_OPERAND (arg0, 1), arg1));
12530 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12531 (X & C) == 0 when C is a single bit. */
12532 if (TREE_CODE (arg0) == BIT_AND_EXPR
12533 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12534 && integer_zerop (arg1)
12535 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12537 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12538 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12539 TREE_OPERAND (arg0, 1));
12540 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12542 fold_convert_loc (loc, TREE_TYPE (arg0),
12546 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12547 constant C is a power of two, i.e. a single bit. */
12548 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12549 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12550 && integer_zerop (arg1)
12551 && integer_pow2p (TREE_OPERAND (arg0, 1))
12552 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12553 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12555 tree arg00 = TREE_OPERAND (arg0, 0);
12556 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12557 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12560 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12561 when is C is a power of two, i.e. a single bit. */
12562 if (TREE_CODE (arg0) == BIT_AND_EXPR
12563 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12564 && integer_zerop (arg1)
12565 && integer_pow2p (TREE_OPERAND (arg0, 1))
12566 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12567 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12569 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12570 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
12571 arg000, TREE_OPERAND (arg0, 1));
12572 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12573 tem, build_int_cst (TREE_TYPE (tem), 0));
12576 if (integer_zerop (arg1)
12577 && tree_expr_nonzero_p (arg0))
12579 tree res = constant_boolean_node (code==NE_EXPR, type);
12580 return omit_one_operand_loc (loc, type, res, arg0);
12583 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12584 if (TREE_CODE (arg0) == NEGATE_EXPR
12585 && TREE_CODE (arg1) == NEGATE_EXPR)
12586 return fold_build2_loc (loc, code, type,
12587 TREE_OPERAND (arg0, 0),
12588 fold_convert_loc (loc, TREE_TYPE (arg0),
12589 TREE_OPERAND (arg1, 0)));
12591 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12592 if (TREE_CODE (arg0) == BIT_AND_EXPR
12593 && TREE_CODE (arg1) == BIT_AND_EXPR)
12595 tree arg00 = TREE_OPERAND (arg0, 0);
12596 tree arg01 = TREE_OPERAND (arg0, 1);
12597 tree arg10 = TREE_OPERAND (arg1, 0);
12598 tree arg11 = TREE_OPERAND (arg1, 1);
12599 tree itype = TREE_TYPE (arg0);
12601 if (operand_equal_p (arg01, arg11, 0))
12602 return fold_build2_loc (loc, code, type,
12603 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12604 fold_build2_loc (loc,
12605 BIT_XOR_EXPR, itype,
12608 build_int_cst (itype, 0));
12610 if (operand_equal_p (arg01, arg10, 0))
12611 return fold_build2_loc (loc, code, type,
12612 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12613 fold_build2_loc (loc,
12614 BIT_XOR_EXPR, itype,
12617 build_int_cst (itype, 0));
12619 if (operand_equal_p (arg00, arg11, 0))
12620 return fold_build2_loc (loc, code, type,
12621 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12622 fold_build2_loc (loc,
12623 BIT_XOR_EXPR, itype,
12626 build_int_cst (itype, 0));
12628 if (operand_equal_p (arg00, arg10, 0))
12629 return fold_build2_loc (loc, code, type,
12630 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12631 fold_build2_loc (loc,
12632 BIT_XOR_EXPR, itype,
12635 build_int_cst (itype, 0));
12638 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12639 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12641 tree arg00 = TREE_OPERAND (arg0, 0);
12642 tree arg01 = TREE_OPERAND (arg0, 1);
12643 tree arg10 = TREE_OPERAND (arg1, 0);
12644 tree arg11 = TREE_OPERAND (arg1, 1);
12645 tree itype = TREE_TYPE (arg0);
12647 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12648 operand_equal_p guarantees no side-effects so we don't need
12649 to use omit_one_operand on Z. */
12650 if (operand_equal_p (arg01, arg11, 0))
12651 return fold_build2_loc (loc, code, type, arg00,
12652 fold_convert_loc (loc, TREE_TYPE (arg00),
12654 if (operand_equal_p (arg01, arg10, 0))
12655 return fold_build2_loc (loc, code, type, arg00,
12656 fold_convert_loc (loc, TREE_TYPE (arg00),
12658 if (operand_equal_p (arg00, arg11, 0))
12659 return fold_build2_loc (loc, code, type, arg01,
12660 fold_convert_loc (loc, TREE_TYPE (arg01),
12662 if (operand_equal_p (arg00, arg10, 0))
12663 return fold_build2_loc (loc, code, type, arg01,
12664 fold_convert_loc (loc, TREE_TYPE (arg01),
12667 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12668 if (TREE_CODE (arg01) == INTEGER_CST
12669 && TREE_CODE (arg11) == INTEGER_CST)
12671 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg01,
12672 fold_convert_loc (loc, itype, arg11));
12673 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00, tem);
12674 return fold_build2_loc (loc, code, type, tem,
12675 fold_convert_loc (loc, itype, arg10));
12679 /* Attempt to simplify equality/inequality comparisons of complex
12680 values. Only lower the comparison if the result is known or
12681 can be simplified to a single scalar comparison. */
12682 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12683 || TREE_CODE (arg0) == COMPLEX_CST)
12684 && (TREE_CODE (arg1) == COMPLEX_EXPR
12685 || TREE_CODE (arg1) == COMPLEX_CST))
12687 tree real0, imag0, real1, imag1;
12690 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12692 real0 = TREE_OPERAND (arg0, 0);
12693 imag0 = TREE_OPERAND (arg0, 1);
12697 real0 = TREE_REALPART (arg0);
12698 imag0 = TREE_IMAGPART (arg0);
12701 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12703 real1 = TREE_OPERAND (arg1, 0);
12704 imag1 = TREE_OPERAND (arg1, 1);
12708 real1 = TREE_REALPART (arg1);
12709 imag1 = TREE_IMAGPART (arg1);
12712 rcond = fold_binary_loc (loc, code, type, real0, real1);
12713 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12715 if (integer_zerop (rcond))
12717 if (code == EQ_EXPR)
12718 return omit_two_operands_loc (loc, type, boolean_false_node,
12720 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
12724 if (code == NE_EXPR)
12725 return omit_two_operands_loc (loc, type, boolean_true_node,
12727 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
12731 icond = fold_binary_loc (loc, code, type, imag0, imag1);
12732 if (icond && TREE_CODE (icond) == INTEGER_CST)
12734 if (integer_zerop (icond))
12736 if (code == EQ_EXPR)
12737 return omit_two_operands_loc (loc, type, boolean_false_node,
12739 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
12743 if (code == NE_EXPR)
12744 return omit_two_operands_loc (loc, type, boolean_true_node,
12746 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
12757 tem = fold_comparison (loc, code, type, op0, op1);
12758 if (tem != NULL_TREE)
12761 /* Transform comparisons of the form X +- C CMP X. */
12762 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12763 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12764 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12765 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12766 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12767 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12769 tree arg01 = TREE_OPERAND (arg0, 1);
12770 enum tree_code code0 = TREE_CODE (arg0);
12773 if (TREE_CODE (arg01) == REAL_CST)
12774 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12776 is_positive = tree_int_cst_sgn (arg01);
12778 /* (X - c) > X becomes false. */
12779 if (code == GT_EXPR
12780 && ((code0 == MINUS_EXPR && is_positive >= 0)
12781 || (code0 == PLUS_EXPR && is_positive <= 0)))
12783 if (TREE_CODE (arg01) == INTEGER_CST
12784 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12785 fold_overflow_warning (("assuming signed overflow does not "
12786 "occur when assuming that (X - c) > X "
12787 "is always false"),
12788 WARN_STRICT_OVERFLOW_ALL);
12789 return constant_boolean_node (0, type);
12792 /* Likewise (X + c) < X becomes false. */
12793 if (code == LT_EXPR
12794 && ((code0 == PLUS_EXPR && is_positive >= 0)
12795 || (code0 == MINUS_EXPR && is_positive <= 0)))
12797 if (TREE_CODE (arg01) == INTEGER_CST
12798 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12799 fold_overflow_warning (("assuming signed overflow does not "
12800 "occur when assuming that "
12801 "(X + c) < X is always false"),
12802 WARN_STRICT_OVERFLOW_ALL);
12803 return constant_boolean_node (0, type);
12806 /* Convert (X - c) <= X to true. */
12807 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12809 && ((code0 == MINUS_EXPR && is_positive >= 0)
12810 || (code0 == PLUS_EXPR && is_positive <= 0)))
12812 if (TREE_CODE (arg01) == INTEGER_CST
12813 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12814 fold_overflow_warning (("assuming signed overflow does not "
12815 "occur when assuming that "
12816 "(X - c) <= X is always true"),
12817 WARN_STRICT_OVERFLOW_ALL);
12818 return constant_boolean_node (1, type);
12821 /* Convert (X + c) >= X to true. */
12822 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12824 && ((code0 == PLUS_EXPR && is_positive >= 0)
12825 || (code0 == MINUS_EXPR && is_positive <= 0)))
12827 if (TREE_CODE (arg01) == INTEGER_CST
12828 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12829 fold_overflow_warning (("assuming signed overflow does not "
12830 "occur when assuming that "
12831 "(X + c) >= X is always true"),
12832 WARN_STRICT_OVERFLOW_ALL);
12833 return constant_boolean_node (1, type);
12836 if (TREE_CODE (arg01) == INTEGER_CST)
12838 /* Convert X + c > X and X - c < X to true for integers. */
12839 if (code == GT_EXPR
12840 && ((code0 == PLUS_EXPR && is_positive > 0)
12841 || (code0 == MINUS_EXPR && is_positive < 0)))
12843 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12844 fold_overflow_warning (("assuming signed overflow does "
12845 "not occur when assuming that "
12846 "(X + c) > X is always true"),
12847 WARN_STRICT_OVERFLOW_ALL);
12848 return constant_boolean_node (1, type);
12851 if (code == LT_EXPR
12852 && ((code0 == MINUS_EXPR && is_positive > 0)
12853 || (code0 == PLUS_EXPR && is_positive < 0)))
12855 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12856 fold_overflow_warning (("assuming signed overflow does "
12857 "not occur when assuming that "
12858 "(X - c) < X is always true"),
12859 WARN_STRICT_OVERFLOW_ALL);
12860 return constant_boolean_node (1, type);
12863 /* Convert X + c <= X and X - c >= X to false for integers. */
12864 if (code == LE_EXPR
12865 && ((code0 == PLUS_EXPR && is_positive > 0)
12866 || (code0 == MINUS_EXPR && is_positive < 0)))
12868 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12869 fold_overflow_warning (("assuming signed overflow does "
12870 "not occur when assuming that "
12871 "(X + c) <= X is always false"),
12872 WARN_STRICT_OVERFLOW_ALL);
12873 return constant_boolean_node (0, type);
12876 if (code == GE_EXPR
12877 && ((code0 == MINUS_EXPR && is_positive > 0)
12878 || (code0 == PLUS_EXPR && is_positive < 0)))
12880 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12881 fold_overflow_warning (("assuming signed overflow does "
12882 "not occur when assuming that "
12883 "(X - c) >= X is always false"),
12884 WARN_STRICT_OVERFLOW_ALL);
12885 return constant_boolean_node (0, type);
12890 /* Comparisons with the highest or lowest possible integer of
12891 the specified precision will have known values. */
12893 tree arg1_type = TREE_TYPE (arg1);
12894 unsigned int width = TYPE_PRECISION (arg1_type);
12896 if (TREE_CODE (arg1) == INTEGER_CST
12897 && width <= 2 * HOST_BITS_PER_WIDE_INT
12898 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12900 HOST_WIDE_INT signed_max_hi;
12901 unsigned HOST_WIDE_INT signed_max_lo;
12902 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12904 if (width <= HOST_BITS_PER_WIDE_INT)
12906 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12911 if (TYPE_UNSIGNED (arg1_type))
12913 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12919 max_lo = signed_max_lo;
12920 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12926 width -= HOST_BITS_PER_WIDE_INT;
12927 signed_max_lo = -1;
12928 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12933 if (TYPE_UNSIGNED (arg1_type))
12935 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12940 max_hi = signed_max_hi;
12941 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12945 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12946 && TREE_INT_CST_LOW (arg1) == max_lo)
12950 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12953 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12956 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12959 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
12961 /* The GE_EXPR and LT_EXPR cases above are not normally
12962 reached because of previous transformations. */
12967 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12969 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12973 arg1 = const_binop (PLUS_EXPR, arg1,
12974 build_int_cst (TREE_TYPE (arg1), 1));
12975 return fold_build2_loc (loc, EQ_EXPR, type,
12976 fold_convert_loc (loc,
12977 TREE_TYPE (arg1), arg0),
12980 arg1 = const_binop (PLUS_EXPR, arg1,
12981 build_int_cst (TREE_TYPE (arg1), 1));
12982 return fold_build2_loc (loc, NE_EXPR, type,
12983 fold_convert_loc (loc, TREE_TYPE (arg1),
12989 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12991 && TREE_INT_CST_LOW (arg1) == min_lo)
12995 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12998 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13001 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13004 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13009 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13011 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13015 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13016 return fold_build2_loc (loc, NE_EXPR, type,
13017 fold_convert_loc (loc,
13018 TREE_TYPE (arg1), arg0),
13021 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13022 return fold_build2_loc (loc, EQ_EXPR, type,
13023 fold_convert_loc (loc, TREE_TYPE (arg1),
13030 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13031 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13032 && TYPE_UNSIGNED (arg1_type)
13033 /* We will flip the signedness of the comparison operator
13034 associated with the mode of arg1, so the sign bit is
13035 specified by this mode. Check that arg1 is the signed
13036 max associated with this sign bit. */
13037 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13038 /* signed_type does not work on pointer types. */
13039 && INTEGRAL_TYPE_P (arg1_type))
13041 /* The following case also applies to X < signed_max+1
13042 and X >= signed_max+1 because previous transformations. */
13043 if (code == LE_EXPR || code == GT_EXPR)
13046 st = signed_type_for (TREE_TYPE (arg1));
13047 return fold_build2_loc (loc,
13048 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13049 type, fold_convert_loc (loc, st, arg0),
13050 build_int_cst (st, 0));
13056 /* If we are comparing an ABS_EXPR with a constant, we can
13057 convert all the cases into explicit comparisons, but they may
13058 well not be faster than doing the ABS and one comparison.
13059 But ABS (X) <= C is a range comparison, which becomes a subtraction
13060 and a comparison, and is probably faster. */
13061 if (code == LE_EXPR
13062 && TREE_CODE (arg1) == INTEGER_CST
13063 && TREE_CODE (arg0) == ABS_EXPR
13064 && ! TREE_SIDE_EFFECTS (arg0)
13065 && (0 != (tem = negate_expr (arg1)))
13066 && TREE_CODE (tem) == INTEGER_CST
13067 && !TREE_OVERFLOW (tem))
13068 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13069 build2 (GE_EXPR, type,
13070 TREE_OPERAND (arg0, 0), tem),
13071 build2 (LE_EXPR, type,
13072 TREE_OPERAND (arg0, 0), arg1));
13074 /* Convert ABS_EXPR<x> >= 0 to true. */
13075 strict_overflow_p = false;
13076 if (code == GE_EXPR
13077 && (integer_zerop (arg1)
13078 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13079 && real_zerop (arg1)))
13080 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13082 if (strict_overflow_p)
13083 fold_overflow_warning (("assuming signed overflow does not occur "
13084 "when simplifying comparison of "
13085 "absolute value and zero"),
13086 WARN_STRICT_OVERFLOW_CONDITIONAL);
13087 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13090 /* Convert ABS_EXPR<x> < 0 to false. */
13091 strict_overflow_p = false;
13092 if (code == LT_EXPR
13093 && (integer_zerop (arg1) || real_zerop (arg1))
13094 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13096 if (strict_overflow_p)
13097 fold_overflow_warning (("assuming signed overflow does not occur "
13098 "when simplifying comparison of "
13099 "absolute value and zero"),
13100 WARN_STRICT_OVERFLOW_CONDITIONAL);
13101 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13104 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13105 and similarly for >= into !=. */
13106 if ((code == LT_EXPR || code == GE_EXPR)
13107 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13108 && TREE_CODE (arg1) == LSHIFT_EXPR
13109 && integer_onep (TREE_OPERAND (arg1, 0)))
13110 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13111 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13112 TREE_OPERAND (arg1, 1)),
13113 build_int_cst (TREE_TYPE (arg0), 0));
13115 if ((code == LT_EXPR || code == GE_EXPR)
13116 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13117 && CONVERT_EXPR_P (arg1)
13118 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13119 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13121 tem = build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13122 TREE_OPERAND (TREE_OPERAND (arg1, 0), 1));
13123 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13124 fold_convert_loc (loc, TREE_TYPE (arg0), tem),
13125 build_int_cst (TREE_TYPE (arg0), 0));
13130 case UNORDERED_EXPR:
13138 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13140 t1 = fold_relational_const (code, type, arg0, arg1);
13141 if (t1 != NULL_TREE)
13145 /* If the first operand is NaN, the result is constant. */
13146 if (TREE_CODE (arg0) == REAL_CST
13147 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13148 && (code != LTGT_EXPR || ! flag_trapping_math))
13150 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13151 ? integer_zero_node
13152 : integer_one_node;
13153 return omit_one_operand_loc (loc, type, t1, arg1);
13156 /* If the second operand is NaN, the result is constant. */
13157 if (TREE_CODE (arg1) == REAL_CST
13158 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13159 && (code != LTGT_EXPR || ! flag_trapping_math))
13161 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13162 ? integer_zero_node
13163 : integer_one_node;
13164 return omit_one_operand_loc (loc, type, t1, arg0);
13167 /* Simplify unordered comparison of something with itself. */
13168 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13169 && operand_equal_p (arg0, arg1, 0))
13170 return constant_boolean_node (1, type);
13172 if (code == LTGT_EXPR
13173 && !flag_trapping_math
13174 && operand_equal_p (arg0, arg1, 0))
13175 return constant_boolean_node (0, type);
13177 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13179 tree targ0 = strip_float_extensions (arg0);
13180 tree targ1 = strip_float_extensions (arg1);
13181 tree newtype = TREE_TYPE (targ0);
13183 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13184 newtype = TREE_TYPE (targ1);
13186 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13187 return fold_build2_loc (loc, code, type,
13188 fold_convert_loc (loc, newtype, targ0),
13189 fold_convert_loc (loc, newtype, targ1));
13194 case COMPOUND_EXPR:
13195 /* When pedantic, a compound expression can be neither an lvalue
13196 nor an integer constant expression. */
13197 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13199 /* Don't let (0, 0) be null pointer constant. */
13200 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13201 : fold_convert_loc (loc, type, arg1);
13202 return pedantic_non_lvalue_loc (loc, tem);
13205 if ((TREE_CODE (arg0) == REAL_CST
13206 && TREE_CODE (arg1) == REAL_CST)
13207 || (TREE_CODE (arg0) == INTEGER_CST
13208 && TREE_CODE (arg1) == INTEGER_CST))
13209 return build_complex (type, arg0, arg1);
13210 if (TREE_CODE (arg0) == REALPART_EXPR
13211 && TREE_CODE (arg1) == IMAGPART_EXPR
13212 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg0, 0)))
13213 == TYPE_MAIN_VARIANT (type))
13214 && operand_equal_p (TREE_OPERAND (arg0, 0),
13215 TREE_OPERAND (arg1, 0), 0))
13216 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
13217 TREE_OPERAND (arg1, 0));
13221 /* An ASSERT_EXPR should never be passed to fold_binary. */
13222 gcc_unreachable ();
13226 } /* switch (code) */
13229 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13230 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13234 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13236 switch (TREE_CODE (*tp))
13242 *walk_subtrees = 0;
13244 /* ... fall through ... */
13251 /* Return whether the sub-tree ST contains a label which is accessible from
13252 outside the sub-tree. */
13255 contains_label_p (tree st)
13258 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13261 /* Fold a ternary expression of code CODE and type TYPE with operands
13262 OP0, OP1, and OP2. Return the folded expression if folding is
13263 successful. Otherwise, return NULL_TREE. */
13266 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13267 tree op0, tree op1, tree op2)
13270 tree arg0 = NULL_TREE, arg1 = NULL_TREE, arg2 = NULL_TREE;
13271 enum tree_code_class kind = TREE_CODE_CLASS (code);
13273 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13274 && TREE_CODE_LENGTH (code) == 3);
13276 /* Strip any conversions that don't change the mode. This is safe
13277 for every expression, except for a comparison expression because
13278 its signedness is derived from its operands. So, in the latter
13279 case, only strip conversions that don't change the signedness.
13281 Note that this is done as an internal manipulation within the
13282 constant folder, in order to find the simplest representation of
13283 the arguments so that their form can be studied. In any cases,
13284 the appropriate type conversions should be put back in the tree
13285 that will get out of the constant folder. */
13306 case COMPONENT_REF:
13307 if (TREE_CODE (arg0) == CONSTRUCTOR
13308 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13310 unsigned HOST_WIDE_INT idx;
13312 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13319 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13320 so all simple results must be passed through pedantic_non_lvalue. */
13321 if (TREE_CODE (arg0) == INTEGER_CST)
13323 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13324 tem = integer_zerop (arg0) ? op2 : op1;
13325 /* Only optimize constant conditions when the selected branch
13326 has the same type as the COND_EXPR. This avoids optimizing
13327 away "c ? x : throw", where the throw has a void type.
13328 Avoid throwing away that operand which contains label. */
13329 if ((!TREE_SIDE_EFFECTS (unused_op)
13330 || !contains_label_p (unused_op))
13331 && (! VOID_TYPE_P (TREE_TYPE (tem))
13332 || VOID_TYPE_P (type)))
13333 return pedantic_non_lvalue_loc (loc, tem);
13336 if (operand_equal_p (arg1, op2, 0))
13337 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13339 /* If we have A op B ? A : C, we may be able to convert this to a
13340 simpler expression, depending on the operation and the values
13341 of B and C. Signed zeros prevent all of these transformations,
13342 for reasons given above each one.
13344 Also try swapping the arguments and inverting the conditional. */
13345 if (COMPARISON_CLASS_P (arg0)
13346 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13347 arg1, TREE_OPERAND (arg0, 1))
13348 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13350 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13355 if (COMPARISON_CLASS_P (arg0)
13356 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13358 TREE_OPERAND (arg0, 1))
13359 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13361 location_t loc0 = expr_location_or (arg0, loc);
13362 tem = fold_truth_not_expr (loc0, arg0);
13363 if (tem && COMPARISON_CLASS_P (tem))
13365 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13371 /* If the second operand is simpler than the third, swap them
13372 since that produces better jump optimization results. */
13373 if (truth_value_p (TREE_CODE (arg0))
13374 && tree_swap_operands_p (op1, op2, false))
13376 location_t loc0 = expr_location_or (arg0, loc);
13377 /* See if this can be inverted. If it can't, possibly because
13378 it was a floating-point inequality comparison, don't do
13380 tem = fold_truth_not_expr (loc0, arg0);
13382 return fold_build3_loc (loc, code, type, tem, op2, op1);
13385 /* Convert A ? 1 : 0 to simply A. */
13386 if (integer_onep (op1)
13387 && integer_zerop (op2)
13388 /* If we try to convert OP0 to our type, the
13389 call to fold will try to move the conversion inside
13390 a COND, which will recurse. In that case, the COND_EXPR
13391 is probably the best choice, so leave it alone. */
13392 && type == TREE_TYPE (arg0))
13393 return pedantic_non_lvalue_loc (loc, arg0);
13395 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13396 over COND_EXPR in cases such as floating point comparisons. */
13397 if (integer_zerop (op1)
13398 && integer_onep (op2)
13399 && truth_value_p (TREE_CODE (arg0)))
13400 return pedantic_non_lvalue_loc (loc,
13401 fold_convert_loc (loc, type,
13402 invert_truthvalue_loc (loc,
13405 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13406 if (TREE_CODE (arg0) == LT_EXPR
13407 && integer_zerop (TREE_OPERAND (arg0, 1))
13408 && integer_zerop (op2)
13409 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13411 /* sign_bit_p only checks ARG1 bits within A's precision.
13412 If <sign bit of A> has wider type than A, bits outside
13413 of A's precision in <sign bit of A> need to be checked.
13414 If they are all 0, this optimization needs to be done
13415 in unsigned A's type, if they are all 1 in signed A's type,
13416 otherwise this can't be done. */
13417 if (TYPE_PRECISION (TREE_TYPE (tem))
13418 < TYPE_PRECISION (TREE_TYPE (arg1))
13419 && TYPE_PRECISION (TREE_TYPE (tem))
13420 < TYPE_PRECISION (type))
13422 unsigned HOST_WIDE_INT mask_lo;
13423 HOST_WIDE_INT mask_hi;
13424 int inner_width, outer_width;
13427 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13428 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13429 if (outer_width > TYPE_PRECISION (type))
13430 outer_width = TYPE_PRECISION (type);
13432 if (outer_width > HOST_BITS_PER_WIDE_INT)
13434 mask_hi = ((unsigned HOST_WIDE_INT) -1
13435 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13441 mask_lo = ((unsigned HOST_WIDE_INT) -1
13442 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13444 if (inner_width > HOST_BITS_PER_WIDE_INT)
13446 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13447 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13451 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13452 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13454 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13455 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13457 tem_type = signed_type_for (TREE_TYPE (tem));
13458 tem = fold_convert_loc (loc, tem_type, tem);
13460 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13461 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13463 tem_type = unsigned_type_for (TREE_TYPE (tem));
13464 tem = fold_convert_loc (loc, tem_type, tem);
13472 fold_convert_loc (loc, type,
13473 fold_build2_loc (loc, BIT_AND_EXPR,
13474 TREE_TYPE (tem), tem,
13475 fold_convert_loc (loc,
13480 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13481 already handled above. */
13482 if (TREE_CODE (arg0) == BIT_AND_EXPR
13483 && integer_onep (TREE_OPERAND (arg0, 1))
13484 && integer_zerop (op2)
13485 && integer_pow2p (arg1))
13487 tree tem = TREE_OPERAND (arg0, 0);
13489 if (TREE_CODE (tem) == RSHIFT_EXPR
13490 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13491 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13492 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13493 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13494 TREE_OPERAND (tem, 0), arg1);
13497 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13498 is probably obsolete because the first operand should be a
13499 truth value (that's why we have the two cases above), but let's
13500 leave it in until we can confirm this for all front-ends. */
13501 if (integer_zerop (op2)
13502 && TREE_CODE (arg0) == NE_EXPR
13503 && integer_zerop (TREE_OPERAND (arg0, 1))
13504 && integer_pow2p (arg1)
13505 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13506 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13507 arg1, OEP_ONLY_CONST))
13508 return pedantic_non_lvalue_loc (loc,
13509 fold_convert_loc (loc, type,
13510 TREE_OPERAND (arg0, 0)));
13512 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13513 if (integer_zerop (op2)
13514 && truth_value_p (TREE_CODE (arg0))
13515 && truth_value_p (TREE_CODE (arg1)))
13516 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13517 fold_convert_loc (loc, type, arg0),
13520 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13521 if (integer_onep (op2)
13522 && truth_value_p (TREE_CODE (arg0))
13523 && truth_value_p (TREE_CODE (arg1)))
13525 location_t loc0 = expr_location_or (arg0, loc);
13526 /* Only perform transformation if ARG0 is easily inverted. */
13527 tem = fold_truth_not_expr (loc0, arg0);
13529 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13530 fold_convert_loc (loc, type, tem),
13534 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13535 if (integer_zerop (arg1)
13536 && truth_value_p (TREE_CODE (arg0))
13537 && truth_value_p (TREE_CODE (op2)))
13539 location_t loc0 = expr_location_or (arg0, loc);
13540 /* Only perform transformation if ARG0 is easily inverted. */
13541 tem = fold_truth_not_expr (loc0, arg0);
13543 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13544 fold_convert_loc (loc, type, tem),
13548 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13549 if (integer_onep (arg1)
13550 && truth_value_p (TREE_CODE (arg0))
13551 && truth_value_p (TREE_CODE (op2)))
13552 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13553 fold_convert_loc (loc, type, arg0),
13559 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13560 of fold_ternary on them. */
13561 gcc_unreachable ();
13563 case BIT_FIELD_REF:
13564 if ((TREE_CODE (arg0) == VECTOR_CST
13565 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13566 && type == TREE_TYPE (TREE_TYPE (arg0)))
13568 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13569 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13572 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13573 && (idx % width) == 0
13574 && (idx = idx / width)
13575 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13577 tree elements = NULL_TREE;
13579 if (TREE_CODE (arg0) == VECTOR_CST)
13580 elements = TREE_VECTOR_CST_ELTS (arg0);
13583 unsigned HOST_WIDE_INT idx;
13586 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13587 elements = tree_cons (NULL_TREE, value, elements);
13589 while (idx-- > 0 && elements)
13590 elements = TREE_CHAIN (elements);
13592 return TREE_VALUE (elements);
13594 return build_zero_cst (type);
13598 /* A bit-field-ref that referenced the full argument can be stripped. */
13599 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13600 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13601 && integer_zerop (op2))
13602 return fold_convert_loc (loc, type, arg0);
13607 /* For integers we can decompose the FMA if possible. */
13608 if (TREE_CODE (arg0) == INTEGER_CST
13609 && TREE_CODE (arg1) == INTEGER_CST)
13610 return fold_build2_loc (loc, PLUS_EXPR, type,
13611 const_binop (MULT_EXPR, arg0, arg1), arg2);
13612 if (integer_zerop (arg2))
13613 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
13615 return fold_fma (loc, type, arg0, arg1, arg2);
13619 } /* switch (code) */
13622 /* Perform constant folding and related simplification of EXPR.
13623 The related simplifications include x*1 => x, x*0 => 0, etc.,
13624 and application of the associative law.
13625 NOP_EXPR conversions may be removed freely (as long as we
13626 are careful not to change the type of the overall expression).
13627 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13628 but we can constant-fold them if they have constant operands. */
13630 #ifdef ENABLE_FOLD_CHECKING
13631 # define fold(x) fold_1 (x)
13632 static tree fold_1 (tree);
13638 const tree t = expr;
13639 enum tree_code code = TREE_CODE (t);
13640 enum tree_code_class kind = TREE_CODE_CLASS (code);
13642 location_t loc = EXPR_LOCATION (expr);
13644 /* Return right away if a constant. */
13645 if (kind == tcc_constant)
13648 /* CALL_EXPR-like objects with variable numbers of operands are
13649 treated specially. */
13650 if (kind == tcc_vl_exp)
13652 if (code == CALL_EXPR)
13654 tem = fold_call_expr (loc, expr, false);
13655 return tem ? tem : expr;
13660 if (IS_EXPR_CODE_CLASS (kind))
13662 tree type = TREE_TYPE (t);
13663 tree op0, op1, op2;
13665 switch (TREE_CODE_LENGTH (code))
13668 op0 = TREE_OPERAND (t, 0);
13669 tem = fold_unary_loc (loc, code, type, op0);
13670 return tem ? tem : expr;
13672 op0 = TREE_OPERAND (t, 0);
13673 op1 = TREE_OPERAND (t, 1);
13674 tem = fold_binary_loc (loc, code, type, op0, op1);
13675 return tem ? tem : expr;
13677 op0 = TREE_OPERAND (t, 0);
13678 op1 = TREE_OPERAND (t, 1);
13679 op2 = TREE_OPERAND (t, 2);
13680 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
13681 return tem ? tem : expr;
13691 tree op0 = TREE_OPERAND (t, 0);
13692 tree op1 = TREE_OPERAND (t, 1);
13694 if (TREE_CODE (op1) == INTEGER_CST
13695 && TREE_CODE (op0) == CONSTRUCTOR
13696 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13698 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13699 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13700 unsigned HOST_WIDE_INT begin = 0;
13702 /* Find a matching index by means of a binary search. */
13703 while (begin != end)
13705 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13706 tree index = VEC_index (constructor_elt, elts, middle)->index;
13708 if (TREE_CODE (index) == INTEGER_CST
13709 && tree_int_cst_lt (index, op1))
13710 begin = middle + 1;
13711 else if (TREE_CODE (index) == INTEGER_CST
13712 && tree_int_cst_lt (op1, index))
13714 else if (TREE_CODE (index) == RANGE_EXPR
13715 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13716 begin = middle + 1;
13717 else if (TREE_CODE (index) == RANGE_EXPR
13718 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13721 return VEC_index (constructor_elt, elts, middle)->value;
13729 return fold (DECL_INITIAL (t));
13733 } /* switch (code) */
13736 #ifdef ENABLE_FOLD_CHECKING
13739 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13740 static void fold_check_failed (const_tree, const_tree);
13741 void print_fold_checksum (const_tree);
13743 /* When --enable-checking=fold, compute a digest of expr before
13744 and after actual fold call to see if fold did not accidentally
13745 change original expr. */
13751 struct md5_ctx ctx;
13752 unsigned char checksum_before[16], checksum_after[16];
13755 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13756 md5_init_ctx (&ctx);
13757 fold_checksum_tree (expr, &ctx, ht);
13758 md5_finish_ctx (&ctx, checksum_before);
13761 ret = fold_1 (expr);
13763 md5_init_ctx (&ctx);
13764 fold_checksum_tree (expr, &ctx, ht);
13765 md5_finish_ctx (&ctx, checksum_after);
13768 if (memcmp (checksum_before, checksum_after, 16))
13769 fold_check_failed (expr, ret);
13775 print_fold_checksum (const_tree expr)
13777 struct md5_ctx ctx;
13778 unsigned char checksum[16], cnt;
13781 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13782 md5_init_ctx (&ctx);
13783 fold_checksum_tree (expr, &ctx, ht);
13784 md5_finish_ctx (&ctx, checksum);
13786 for (cnt = 0; cnt < 16; ++cnt)
13787 fprintf (stderr, "%02x", checksum[cnt]);
13788 putc ('\n', stderr);
13792 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13794 internal_error ("fold check: original tree changed by fold");
13798 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13801 enum tree_code code;
13802 union tree_node buf;
13807 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13808 <= sizeof (struct tree_function_decl))
13809 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13812 slot = (void **) htab_find_slot (ht, expr, INSERT);
13815 *slot = CONST_CAST_TREE (expr);
13816 code = TREE_CODE (expr);
13817 if (TREE_CODE_CLASS (code) == tcc_declaration
13818 && DECL_ASSEMBLER_NAME_SET_P (expr))
13820 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13821 memcpy ((char *) &buf, expr, tree_size (expr));
13822 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13823 expr = (tree) &buf;
13825 else if (TREE_CODE_CLASS (code) == tcc_type
13826 && (TYPE_POINTER_TO (expr)
13827 || TYPE_REFERENCE_TO (expr)
13828 || TYPE_CACHED_VALUES_P (expr)
13829 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13830 || TYPE_NEXT_VARIANT (expr)))
13832 /* Allow these fields to be modified. */
13834 memcpy ((char *) &buf, expr, tree_size (expr));
13835 expr = tmp = (tree) &buf;
13836 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13837 TYPE_POINTER_TO (tmp) = NULL;
13838 TYPE_REFERENCE_TO (tmp) = NULL;
13839 TYPE_NEXT_VARIANT (tmp) = NULL;
13840 if (TYPE_CACHED_VALUES_P (tmp))
13842 TYPE_CACHED_VALUES_P (tmp) = 0;
13843 TYPE_CACHED_VALUES (tmp) = NULL;
13846 md5_process_bytes (expr, tree_size (expr), ctx);
13847 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13848 if (TREE_CODE_CLASS (code) != tcc_type
13849 && TREE_CODE_CLASS (code) != tcc_declaration
13850 && code != TREE_LIST
13851 && code != SSA_NAME
13852 && CODE_CONTAINS_STRUCT (code, TS_COMMON))
13853 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13854 switch (TREE_CODE_CLASS (code))
13860 md5_process_bytes (TREE_STRING_POINTER (expr),
13861 TREE_STRING_LENGTH (expr), ctx);
13864 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13865 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13868 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13874 case tcc_exceptional:
13878 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13879 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13880 expr = TREE_CHAIN (expr);
13881 goto recursive_label;
13884 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13885 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13891 case tcc_expression:
13892 case tcc_reference:
13893 case tcc_comparison:
13896 case tcc_statement:
13898 len = TREE_OPERAND_LENGTH (expr);
13899 for (i = 0; i < len; ++i)
13900 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13902 case tcc_declaration:
13903 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13904 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13905 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13907 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13908 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13909 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13910 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13911 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13913 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13914 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13916 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13918 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13919 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13920 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13924 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13925 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13926 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13927 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13928 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13929 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13930 if (INTEGRAL_TYPE_P (expr)
13931 || SCALAR_FLOAT_TYPE_P (expr))
13933 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13934 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13936 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13937 if (TREE_CODE (expr) == RECORD_TYPE
13938 || TREE_CODE (expr) == UNION_TYPE
13939 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13940 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13941 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13948 /* Helper function for outputting the checksum of a tree T. When
13949 debugging with gdb, you can "define mynext" to be "next" followed
13950 by "call debug_fold_checksum (op0)", then just trace down till the
13953 DEBUG_FUNCTION void
13954 debug_fold_checksum (const_tree t)
13957 unsigned char checksum[16];
13958 struct md5_ctx ctx;
13959 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13961 md5_init_ctx (&ctx);
13962 fold_checksum_tree (t, &ctx, ht);
13963 md5_finish_ctx (&ctx, checksum);
13966 for (i = 0; i < 16; i++)
13967 fprintf (stderr, "%d ", checksum[i]);
13969 fprintf (stderr, "\n");
13974 /* Fold a unary tree expression with code CODE of type TYPE with an
13975 operand OP0. LOC is the location of the resulting expression.
13976 Return a folded expression if successful. Otherwise, return a tree
13977 expression with code CODE of type TYPE with an operand OP0. */
13980 fold_build1_stat_loc (location_t loc,
13981 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13984 #ifdef ENABLE_FOLD_CHECKING
13985 unsigned char checksum_before[16], checksum_after[16];
13986 struct md5_ctx ctx;
13989 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13990 md5_init_ctx (&ctx);
13991 fold_checksum_tree (op0, &ctx, ht);
13992 md5_finish_ctx (&ctx, checksum_before);
13996 tem = fold_unary_loc (loc, code, type, op0);
13998 tem = build1_stat_loc (loc, code, type, op0 PASS_MEM_STAT);
14000 #ifdef ENABLE_FOLD_CHECKING
14001 md5_init_ctx (&ctx);
14002 fold_checksum_tree (op0, &ctx, ht);
14003 md5_finish_ctx (&ctx, checksum_after);
14006 if (memcmp (checksum_before, checksum_after, 16))
14007 fold_check_failed (op0, tem);
14012 /* Fold a binary tree expression with code CODE of type TYPE with
14013 operands OP0 and OP1. LOC is the location of the resulting
14014 expression. Return a folded expression if successful. Otherwise,
14015 return a tree expression with code CODE of type TYPE with operands
14019 fold_build2_stat_loc (location_t loc,
14020 enum tree_code code, tree type, tree op0, tree op1
14024 #ifdef ENABLE_FOLD_CHECKING
14025 unsigned char checksum_before_op0[16],
14026 checksum_before_op1[16],
14027 checksum_after_op0[16],
14028 checksum_after_op1[16];
14029 struct md5_ctx ctx;
14032 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14033 md5_init_ctx (&ctx);
14034 fold_checksum_tree (op0, &ctx, ht);
14035 md5_finish_ctx (&ctx, checksum_before_op0);
14038 md5_init_ctx (&ctx);
14039 fold_checksum_tree (op1, &ctx, ht);
14040 md5_finish_ctx (&ctx, checksum_before_op1);
14044 tem = fold_binary_loc (loc, code, type, op0, op1);
14046 tem = build2_stat_loc (loc, code, type, op0, op1 PASS_MEM_STAT);
14048 #ifdef ENABLE_FOLD_CHECKING
14049 md5_init_ctx (&ctx);
14050 fold_checksum_tree (op0, &ctx, ht);
14051 md5_finish_ctx (&ctx, checksum_after_op0);
14054 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14055 fold_check_failed (op0, tem);
14057 md5_init_ctx (&ctx);
14058 fold_checksum_tree (op1, &ctx, ht);
14059 md5_finish_ctx (&ctx, checksum_after_op1);
14062 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14063 fold_check_failed (op1, tem);
14068 /* Fold a ternary tree expression with code CODE of type TYPE with
14069 operands OP0, OP1, and OP2. Return a folded expression if
14070 successful. Otherwise, return a tree expression with code CODE of
14071 type TYPE with operands OP0, OP1, and OP2. */
14074 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14075 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14078 #ifdef ENABLE_FOLD_CHECKING
14079 unsigned char checksum_before_op0[16],
14080 checksum_before_op1[16],
14081 checksum_before_op2[16],
14082 checksum_after_op0[16],
14083 checksum_after_op1[16],
14084 checksum_after_op2[16];
14085 struct md5_ctx ctx;
14088 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14089 md5_init_ctx (&ctx);
14090 fold_checksum_tree (op0, &ctx, ht);
14091 md5_finish_ctx (&ctx, checksum_before_op0);
14094 md5_init_ctx (&ctx);
14095 fold_checksum_tree (op1, &ctx, ht);
14096 md5_finish_ctx (&ctx, checksum_before_op1);
14099 md5_init_ctx (&ctx);
14100 fold_checksum_tree (op2, &ctx, ht);
14101 md5_finish_ctx (&ctx, checksum_before_op2);
14105 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14106 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14108 tem = build3_stat_loc (loc, code, type, op0, op1, op2 PASS_MEM_STAT);
14110 #ifdef ENABLE_FOLD_CHECKING
14111 md5_init_ctx (&ctx);
14112 fold_checksum_tree (op0, &ctx, ht);
14113 md5_finish_ctx (&ctx, checksum_after_op0);
14116 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14117 fold_check_failed (op0, tem);
14119 md5_init_ctx (&ctx);
14120 fold_checksum_tree (op1, &ctx, ht);
14121 md5_finish_ctx (&ctx, checksum_after_op1);
14124 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14125 fold_check_failed (op1, tem);
14127 md5_init_ctx (&ctx);
14128 fold_checksum_tree (op2, &ctx, ht);
14129 md5_finish_ctx (&ctx, checksum_after_op2);
14132 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14133 fold_check_failed (op2, tem);
14138 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14139 arguments in ARGARRAY, and a null static chain.
14140 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14141 of type TYPE from the given operands as constructed by build_call_array. */
14144 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14145 int nargs, tree *argarray)
14148 #ifdef ENABLE_FOLD_CHECKING
14149 unsigned char checksum_before_fn[16],
14150 checksum_before_arglist[16],
14151 checksum_after_fn[16],
14152 checksum_after_arglist[16];
14153 struct md5_ctx ctx;
14157 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14158 md5_init_ctx (&ctx);
14159 fold_checksum_tree (fn, &ctx, ht);
14160 md5_finish_ctx (&ctx, checksum_before_fn);
14163 md5_init_ctx (&ctx);
14164 for (i = 0; i < nargs; i++)
14165 fold_checksum_tree (argarray[i], &ctx, ht);
14166 md5_finish_ctx (&ctx, checksum_before_arglist);
14170 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14172 #ifdef ENABLE_FOLD_CHECKING
14173 md5_init_ctx (&ctx);
14174 fold_checksum_tree (fn, &ctx, ht);
14175 md5_finish_ctx (&ctx, checksum_after_fn);
14178 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14179 fold_check_failed (fn, tem);
14181 md5_init_ctx (&ctx);
14182 for (i = 0; i < nargs; i++)
14183 fold_checksum_tree (argarray[i], &ctx, ht);
14184 md5_finish_ctx (&ctx, checksum_after_arglist);
14187 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14188 fold_check_failed (NULL_TREE, tem);
14193 /* Perform constant folding and related simplification of initializer
14194 expression EXPR. These behave identically to "fold_buildN" but ignore
14195 potential run-time traps and exceptions that fold must preserve. */
14197 #define START_FOLD_INIT \
14198 int saved_signaling_nans = flag_signaling_nans;\
14199 int saved_trapping_math = flag_trapping_math;\
14200 int saved_rounding_math = flag_rounding_math;\
14201 int saved_trapv = flag_trapv;\
14202 int saved_folding_initializer = folding_initializer;\
14203 flag_signaling_nans = 0;\
14204 flag_trapping_math = 0;\
14205 flag_rounding_math = 0;\
14207 folding_initializer = 1;
14209 #define END_FOLD_INIT \
14210 flag_signaling_nans = saved_signaling_nans;\
14211 flag_trapping_math = saved_trapping_math;\
14212 flag_rounding_math = saved_rounding_math;\
14213 flag_trapv = saved_trapv;\
14214 folding_initializer = saved_folding_initializer;
14217 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14218 tree type, tree op)
14223 result = fold_build1_loc (loc, code, type, op);
14230 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14231 tree type, tree op0, tree op1)
14236 result = fold_build2_loc (loc, code, type, op0, op1);
14243 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14244 tree type, tree op0, tree op1, tree op2)
14249 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14256 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14257 int nargs, tree *argarray)
14262 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14268 #undef START_FOLD_INIT
14269 #undef END_FOLD_INIT
14271 /* Determine if first argument is a multiple of second argument. Return 0 if
14272 it is not, or we cannot easily determined it to be.
14274 An example of the sort of thing we care about (at this point; this routine
14275 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14276 fold cases do now) is discovering that
14278 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14284 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14286 This code also handles discovering that
14288 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14290 is a multiple of 8 so we don't have to worry about dealing with a
14291 possible remainder.
14293 Note that we *look* inside a SAVE_EXPR only to determine how it was
14294 calculated; it is not safe for fold to do much of anything else with the
14295 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14296 at run time. For example, the latter example above *cannot* be implemented
14297 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14298 evaluation time of the original SAVE_EXPR is not necessarily the same at
14299 the time the new expression is evaluated. The only optimization of this
14300 sort that would be valid is changing
14302 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14306 SAVE_EXPR (I) * SAVE_EXPR (J)
14308 (where the same SAVE_EXPR (J) is used in the original and the
14309 transformed version). */
14312 multiple_of_p (tree type, const_tree top, const_tree bottom)
14314 if (operand_equal_p (top, bottom, 0))
14317 if (TREE_CODE (type) != INTEGER_TYPE)
14320 switch (TREE_CODE (top))
14323 /* Bitwise and provides a power of two multiple. If the mask is
14324 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14325 if (!integer_pow2p (bottom))
14330 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14331 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14335 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14336 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14339 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14343 op1 = TREE_OPERAND (top, 1);
14344 /* const_binop may not detect overflow correctly,
14345 so check for it explicitly here. */
14346 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14347 > TREE_INT_CST_LOW (op1)
14348 && TREE_INT_CST_HIGH (op1) == 0
14349 && 0 != (t1 = fold_convert (type,
14350 const_binop (LSHIFT_EXPR,
14353 && !TREE_OVERFLOW (t1))
14354 return multiple_of_p (type, t1, bottom);
14359 /* Can't handle conversions from non-integral or wider integral type. */
14360 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14361 || (TYPE_PRECISION (type)
14362 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14365 /* .. fall through ... */
14368 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14371 return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
14372 && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
14375 if (TREE_CODE (bottom) != INTEGER_CST
14376 || integer_zerop (bottom)
14377 || (TYPE_UNSIGNED (type)
14378 && (tree_int_cst_sgn (top) < 0
14379 || tree_int_cst_sgn (bottom) < 0)))
14381 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14389 /* Return true if CODE or TYPE is known to be non-negative. */
14392 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14394 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14395 && truth_value_p (code))
14396 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14397 have a signed:1 type (where the value is -1 and 0). */
14402 /* Return true if (CODE OP0) is known to be non-negative. If the return
14403 value is based on the assumption that signed overflow is undefined,
14404 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14405 *STRICT_OVERFLOW_P. */
14408 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14409 bool *strict_overflow_p)
14411 if (TYPE_UNSIGNED (type))
14417 /* We can't return 1 if flag_wrapv is set because
14418 ABS_EXPR<INT_MIN> = INT_MIN. */
14419 if (!INTEGRAL_TYPE_P (type))
14421 if (TYPE_OVERFLOW_UNDEFINED (type))
14423 *strict_overflow_p = true;
14428 case NON_LVALUE_EXPR:
14430 case FIX_TRUNC_EXPR:
14431 return tree_expr_nonnegative_warnv_p (op0,
14432 strict_overflow_p);
14436 tree inner_type = TREE_TYPE (op0);
14437 tree outer_type = type;
14439 if (TREE_CODE (outer_type) == REAL_TYPE)
14441 if (TREE_CODE (inner_type) == REAL_TYPE)
14442 return tree_expr_nonnegative_warnv_p (op0,
14443 strict_overflow_p);
14444 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14446 if (TYPE_UNSIGNED (inner_type))
14448 return tree_expr_nonnegative_warnv_p (op0,
14449 strict_overflow_p);
14452 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14454 if (TREE_CODE (inner_type) == REAL_TYPE)
14455 return tree_expr_nonnegative_warnv_p (op0,
14456 strict_overflow_p);
14457 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14458 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14459 && TYPE_UNSIGNED (inner_type);
14465 return tree_simple_nonnegative_warnv_p (code, type);
14468 /* We don't know sign of `t', so be conservative and return false. */
14472 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14473 value is based on the assumption that signed overflow is undefined,
14474 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14475 *STRICT_OVERFLOW_P. */
14478 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14479 tree op1, bool *strict_overflow_p)
14481 if (TYPE_UNSIGNED (type))
14486 case POINTER_PLUS_EXPR:
14488 if (FLOAT_TYPE_P (type))
14489 return (tree_expr_nonnegative_warnv_p (op0,
14491 && tree_expr_nonnegative_warnv_p (op1,
14492 strict_overflow_p));
14494 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14495 both unsigned and at least 2 bits shorter than the result. */
14496 if (TREE_CODE (type) == INTEGER_TYPE
14497 && TREE_CODE (op0) == NOP_EXPR
14498 && TREE_CODE (op1) == NOP_EXPR)
14500 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14501 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14502 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14503 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14505 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14506 TYPE_PRECISION (inner2)) + 1;
14507 return prec < TYPE_PRECISION (type);
14513 if (FLOAT_TYPE_P (type))
14515 /* x * x for floating point x is always non-negative. */
14516 if (operand_equal_p (op0, op1, 0))
14518 return (tree_expr_nonnegative_warnv_p (op0,
14520 && tree_expr_nonnegative_warnv_p (op1,
14521 strict_overflow_p));
14524 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14525 both unsigned and their total bits is shorter than the result. */
14526 if (TREE_CODE (type) == INTEGER_TYPE
14527 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14528 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14530 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14531 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14533 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14534 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14537 bool unsigned0 = TYPE_UNSIGNED (inner0);
14538 bool unsigned1 = TYPE_UNSIGNED (inner1);
14540 if (TREE_CODE (op0) == INTEGER_CST)
14541 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14543 if (TREE_CODE (op1) == INTEGER_CST)
14544 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14546 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14547 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14549 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14550 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14551 : TYPE_PRECISION (inner0);
14553 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14554 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14555 : TYPE_PRECISION (inner1);
14557 return precision0 + precision1 < TYPE_PRECISION (type);
14564 return (tree_expr_nonnegative_warnv_p (op0,
14566 || tree_expr_nonnegative_warnv_p (op1,
14567 strict_overflow_p));
14573 case TRUNC_DIV_EXPR:
14574 case CEIL_DIV_EXPR:
14575 case FLOOR_DIV_EXPR:
14576 case ROUND_DIV_EXPR:
14577 return (tree_expr_nonnegative_warnv_p (op0,
14579 && tree_expr_nonnegative_warnv_p (op1,
14580 strict_overflow_p));
14582 case TRUNC_MOD_EXPR:
14583 case CEIL_MOD_EXPR:
14584 case FLOOR_MOD_EXPR:
14585 case ROUND_MOD_EXPR:
14586 return tree_expr_nonnegative_warnv_p (op0,
14587 strict_overflow_p);
14589 return tree_simple_nonnegative_warnv_p (code, type);
14592 /* We don't know sign of `t', so be conservative and return false. */
14596 /* Return true if T is known to be non-negative. If the return
14597 value is based on the assumption that signed overflow is undefined,
14598 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14599 *STRICT_OVERFLOW_P. */
14602 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14604 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14607 switch (TREE_CODE (t))
14610 return tree_int_cst_sgn (t) >= 0;
14613 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14616 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14619 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14621 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14622 strict_overflow_p));
14624 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14627 /* We don't know sign of `t', so be conservative and return false. */
14631 /* Return true if T is known to be non-negative. If the return
14632 value is based on the assumption that signed overflow is undefined,
14633 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14634 *STRICT_OVERFLOW_P. */
14637 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14638 tree arg0, tree arg1, bool *strict_overflow_p)
14640 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14641 switch (DECL_FUNCTION_CODE (fndecl))
14643 CASE_FLT_FN (BUILT_IN_ACOS):
14644 CASE_FLT_FN (BUILT_IN_ACOSH):
14645 CASE_FLT_FN (BUILT_IN_CABS):
14646 CASE_FLT_FN (BUILT_IN_COSH):
14647 CASE_FLT_FN (BUILT_IN_ERFC):
14648 CASE_FLT_FN (BUILT_IN_EXP):
14649 CASE_FLT_FN (BUILT_IN_EXP10):
14650 CASE_FLT_FN (BUILT_IN_EXP2):
14651 CASE_FLT_FN (BUILT_IN_FABS):
14652 CASE_FLT_FN (BUILT_IN_FDIM):
14653 CASE_FLT_FN (BUILT_IN_HYPOT):
14654 CASE_FLT_FN (BUILT_IN_POW10):
14655 CASE_INT_FN (BUILT_IN_FFS):
14656 CASE_INT_FN (BUILT_IN_PARITY):
14657 CASE_INT_FN (BUILT_IN_POPCOUNT):
14658 case BUILT_IN_BSWAP32:
14659 case BUILT_IN_BSWAP64:
14663 CASE_FLT_FN (BUILT_IN_SQRT):
14664 /* sqrt(-0.0) is -0.0. */
14665 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14667 return tree_expr_nonnegative_warnv_p (arg0,
14668 strict_overflow_p);
14670 CASE_FLT_FN (BUILT_IN_ASINH):
14671 CASE_FLT_FN (BUILT_IN_ATAN):
14672 CASE_FLT_FN (BUILT_IN_ATANH):
14673 CASE_FLT_FN (BUILT_IN_CBRT):
14674 CASE_FLT_FN (BUILT_IN_CEIL):
14675 CASE_FLT_FN (BUILT_IN_ERF):
14676 CASE_FLT_FN (BUILT_IN_EXPM1):
14677 CASE_FLT_FN (BUILT_IN_FLOOR):
14678 CASE_FLT_FN (BUILT_IN_FMOD):
14679 CASE_FLT_FN (BUILT_IN_FREXP):
14680 CASE_FLT_FN (BUILT_IN_LCEIL):
14681 CASE_FLT_FN (BUILT_IN_LDEXP):
14682 CASE_FLT_FN (BUILT_IN_LFLOOR):
14683 CASE_FLT_FN (BUILT_IN_LLCEIL):
14684 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14685 CASE_FLT_FN (BUILT_IN_LLRINT):
14686 CASE_FLT_FN (BUILT_IN_LLROUND):
14687 CASE_FLT_FN (BUILT_IN_LRINT):
14688 CASE_FLT_FN (BUILT_IN_LROUND):
14689 CASE_FLT_FN (BUILT_IN_MODF):
14690 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14691 CASE_FLT_FN (BUILT_IN_RINT):
14692 CASE_FLT_FN (BUILT_IN_ROUND):
14693 CASE_FLT_FN (BUILT_IN_SCALB):
14694 CASE_FLT_FN (BUILT_IN_SCALBLN):
14695 CASE_FLT_FN (BUILT_IN_SCALBN):
14696 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14697 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14698 CASE_FLT_FN (BUILT_IN_SINH):
14699 CASE_FLT_FN (BUILT_IN_TANH):
14700 CASE_FLT_FN (BUILT_IN_TRUNC):
14701 /* True if the 1st argument is nonnegative. */
14702 return tree_expr_nonnegative_warnv_p (arg0,
14703 strict_overflow_p);
14705 CASE_FLT_FN (BUILT_IN_FMAX):
14706 /* True if the 1st OR 2nd arguments are nonnegative. */
14707 return (tree_expr_nonnegative_warnv_p (arg0,
14709 || (tree_expr_nonnegative_warnv_p (arg1,
14710 strict_overflow_p)));
14712 CASE_FLT_FN (BUILT_IN_FMIN):
14713 /* True if the 1st AND 2nd arguments are nonnegative. */
14714 return (tree_expr_nonnegative_warnv_p (arg0,
14716 && (tree_expr_nonnegative_warnv_p (arg1,
14717 strict_overflow_p)));
14719 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14720 /* True if the 2nd argument is nonnegative. */
14721 return tree_expr_nonnegative_warnv_p (arg1,
14722 strict_overflow_p);
14724 CASE_FLT_FN (BUILT_IN_POWI):
14725 /* True if the 1st argument is nonnegative or the second
14726 argument is an even integer. */
14727 if (TREE_CODE (arg1) == INTEGER_CST
14728 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14730 return tree_expr_nonnegative_warnv_p (arg0,
14731 strict_overflow_p);
14733 CASE_FLT_FN (BUILT_IN_POW):
14734 /* True if the 1st argument is nonnegative or the second
14735 argument is an even integer valued real. */
14736 if (TREE_CODE (arg1) == REAL_CST)
14741 c = TREE_REAL_CST (arg1);
14742 n = real_to_integer (&c);
14745 REAL_VALUE_TYPE cint;
14746 real_from_integer (&cint, VOIDmode, n,
14747 n < 0 ? -1 : 0, 0);
14748 if (real_identical (&c, &cint))
14752 return tree_expr_nonnegative_warnv_p (arg0,
14753 strict_overflow_p);
14758 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14762 /* Return true if T is known to be non-negative. If the return
14763 value is based on the assumption that signed overflow is undefined,
14764 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14765 *STRICT_OVERFLOW_P. */
14768 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14770 enum tree_code code = TREE_CODE (t);
14771 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14778 tree temp = TARGET_EXPR_SLOT (t);
14779 t = TARGET_EXPR_INITIAL (t);
14781 /* If the initializer is non-void, then it's a normal expression
14782 that will be assigned to the slot. */
14783 if (!VOID_TYPE_P (t))
14784 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14786 /* Otherwise, the initializer sets the slot in some way. One common
14787 way is an assignment statement at the end of the initializer. */
14790 if (TREE_CODE (t) == BIND_EXPR)
14791 t = expr_last (BIND_EXPR_BODY (t));
14792 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14793 || TREE_CODE (t) == TRY_CATCH_EXPR)
14794 t = expr_last (TREE_OPERAND (t, 0));
14795 else if (TREE_CODE (t) == STATEMENT_LIST)
14800 if (TREE_CODE (t) == MODIFY_EXPR
14801 && TREE_OPERAND (t, 0) == temp)
14802 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14803 strict_overflow_p);
14810 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14811 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14813 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14814 get_callee_fndecl (t),
14817 strict_overflow_p);
14819 case COMPOUND_EXPR:
14821 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14822 strict_overflow_p);
14824 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14825 strict_overflow_p);
14827 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14828 strict_overflow_p);
14831 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14835 /* We don't know sign of `t', so be conservative and return false. */
14839 /* Return true if T is known to be non-negative. If the return
14840 value is based on the assumption that signed overflow is undefined,
14841 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14842 *STRICT_OVERFLOW_P. */
14845 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14847 enum tree_code code;
14848 if (t == error_mark_node)
14851 code = TREE_CODE (t);
14852 switch (TREE_CODE_CLASS (code))
14855 case tcc_comparison:
14856 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14858 TREE_OPERAND (t, 0),
14859 TREE_OPERAND (t, 1),
14860 strict_overflow_p);
14863 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14865 TREE_OPERAND (t, 0),
14866 strict_overflow_p);
14869 case tcc_declaration:
14870 case tcc_reference:
14871 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14879 case TRUTH_AND_EXPR:
14880 case TRUTH_OR_EXPR:
14881 case TRUTH_XOR_EXPR:
14882 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14884 TREE_OPERAND (t, 0),
14885 TREE_OPERAND (t, 1),
14886 strict_overflow_p);
14887 case TRUTH_NOT_EXPR:
14888 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14890 TREE_OPERAND (t, 0),
14891 strict_overflow_p);
14898 case WITH_SIZE_EXPR:
14900 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14903 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14907 /* Return true if `t' is known to be non-negative. Handle warnings
14908 about undefined signed overflow. */
14911 tree_expr_nonnegative_p (tree t)
14913 bool ret, strict_overflow_p;
14915 strict_overflow_p = false;
14916 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14917 if (strict_overflow_p)
14918 fold_overflow_warning (("assuming signed overflow does not occur when "
14919 "determining that expression is always "
14921 WARN_STRICT_OVERFLOW_MISC);
14926 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14927 For floating point we further ensure that T is not denormal.
14928 Similar logic is present in nonzero_address in rtlanal.h.
14930 If the return value is based on the assumption that signed overflow
14931 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14932 change *STRICT_OVERFLOW_P. */
14935 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14936 bool *strict_overflow_p)
14941 return tree_expr_nonzero_warnv_p (op0,
14942 strict_overflow_p);
14946 tree inner_type = TREE_TYPE (op0);
14947 tree outer_type = type;
14949 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14950 && tree_expr_nonzero_warnv_p (op0,
14951 strict_overflow_p));
14955 case NON_LVALUE_EXPR:
14956 return tree_expr_nonzero_warnv_p (op0,
14957 strict_overflow_p);
14966 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14967 For floating point we further ensure that T is not denormal.
14968 Similar logic is present in nonzero_address in rtlanal.h.
14970 If the return value is based on the assumption that signed overflow
14971 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14972 change *STRICT_OVERFLOW_P. */
14975 tree_binary_nonzero_warnv_p (enum tree_code code,
14978 tree op1, bool *strict_overflow_p)
14980 bool sub_strict_overflow_p;
14983 case POINTER_PLUS_EXPR:
14985 if (TYPE_OVERFLOW_UNDEFINED (type))
14987 /* With the presence of negative values it is hard
14988 to say something. */
14989 sub_strict_overflow_p = false;
14990 if (!tree_expr_nonnegative_warnv_p (op0,
14991 &sub_strict_overflow_p)
14992 || !tree_expr_nonnegative_warnv_p (op1,
14993 &sub_strict_overflow_p))
14995 /* One of operands must be positive and the other non-negative. */
14996 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14997 overflows, on a twos-complement machine the sum of two
14998 nonnegative numbers can never be zero. */
14999 return (tree_expr_nonzero_warnv_p (op0,
15001 || tree_expr_nonzero_warnv_p (op1,
15002 strict_overflow_p));
15007 if (TYPE_OVERFLOW_UNDEFINED (type))
15009 if (tree_expr_nonzero_warnv_p (op0,
15011 && tree_expr_nonzero_warnv_p (op1,
15012 strict_overflow_p))
15014 *strict_overflow_p = true;
15021 sub_strict_overflow_p = false;
15022 if (tree_expr_nonzero_warnv_p (op0,
15023 &sub_strict_overflow_p)
15024 && tree_expr_nonzero_warnv_p (op1,
15025 &sub_strict_overflow_p))
15027 if (sub_strict_overflow_p)
15028 *strict_overflow_p = true;
15033 sub_strict_overflow_p = false;
15034 if (tree_expr_nonzero_warnv_p (op0,
15035 &sub_strict_overflow_p))
15037 if (sub_strict_overflow_p)
15038 *strict_overflow_p = true;
15040 /* When both operands are nonzero, then MAX must be too. */
15041 if (tree_expr_nonzero_warnv_p (op1,
15042 strict_overflow_p))
15045 /* MAX where operand 0 is positive is positive. */
15046 return tree_expr_nonnegative_warnv_p (op0,
15047 strict_overflow_p);
15049 /* MAX where operand 1 is positive is positive. */
15050 else if (tree_expr_nonzero_warnv_p (op1,
15051 &sub_strict_overflow_p)
15052 && tree_expr_nonnegative_warnv_p (op1,
15053 &sub_strict_overflow_p))
15055 if (sub_strict_overflow_p)
15056 *strict_overflow_p = true;
15062 return (tree_expr_nonzero_warnv_p (op1,
15064 || tree_expr_nonzero_warnv_p (op0,
15065 strict_overflow_p));
15074 /* Return true when T is an address and is known to be nonzero.
15075 For floating point we further ensure that T is not denormal.
15076 Similar logic is present in nonzero_address in rtlanal.h.
15078 If the return value is based on the assumption that signed overflow
15079 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15080 change *STRICT_OVERFLOW_P. */
15083 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15085 bool sub_strict_overflow_p;
15086 switch (TREE_CODE (t))
15089 return !integer_zerop (t);
15093 tree base = TREE_OPERAND (t, 0);
15094 if (!DECL_P (base))
15095 base = get_base_address (base);
15100 /* Weak declarations may link to NULL. Other things may also be NULL
15101 so protect with -fdelete-null-pointer-checks; but not variables
15102 allocated on the stack. */
15104 && (flag_delete_null_pointer_checks
15105 || (DECL_CONTEXT (base)
15106 && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
15107 && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
15108 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15110 /* Constants are never weak. */
15111 if (CONSTANT_CLASS_P (base))
15118 sub_strict_overflow_p = false;
15119 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15120 &sub_strict_overflow_p)
15121 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15122 &sub_strict_overflow_p))
15124 if (sub_strict_overflow_p)
15125 *strict_overflow_p = true;
15136 /* Return true when T is an address and is known to be nonzero.
15137 For floating point we further ensure that T is not denormal.
15138 Similar logic is present in nonzero_address in rtlanal.h.
15140 If the return value is based on the assumption that signed overflow
15141 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15142 change *STRICT_OVERFLOW_P. */
15145 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15147 tree type = TREE_TYPE (t);
15148 enum tree_code code;
15150 /* Doing something useful for floating point would need more work. */
15151 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15154 code = TREE_CODE (t);
15155 switch (TREE_CODE_CLASS (code))
15158 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15159 strict_overflow_p);
15161 case tcc_comparison:
15162 return tree_binary_nonzero_warnv_p (code, type,
15163 TREE_OPERAND (t, 0),
15164 TREE_OPERAND (t, 1),
15165 strict_overflow_p);
15167 case tcc_declaration:
15168 case tcc_reference:
15169 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15177 case TRUTH_NOT_EXPR:
15178 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15179 strict_overflow_p);
15181 case TRUTH_AND_EXPR:
15182 case TRUTH_OR_EXPR:
15183 case TRUTH_XOR_EXPR:
15184 return tree_binary_nonzero_warnv_p (code, type,
15185 TREE_OPERAND (t, 0),
15186 TREE_OPERAND (t, 1),
15187 strict_overflow_p);
15194 case WITH_SIZE_EXPR:
15196 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15198 case COMPOUND_EXPR:
15201 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15202 strict_overflow_p);
15205 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15206 strict_overflow_p);
15209 return alloca_call_p (t);
15217 /* Return true when T is an address and is known to be nonzero.
15218 Handle warnings about undefined signed overflow. */
15221 tree_expr_nonzero_p (tree t)
15223 bool ret, strict_overflow_p;
15225 strict_overflow_p = false;
15226 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15227 if (strict_overflow_p)
15228 fold_overflow_warning (("assuming signed overflow does not occur when "
15229 "determining that expression is always "
15231 WARN_STRICT_OVERFLOW_MISC);
15235 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15236 attempt to fold the expression to a constant without modifying TYPE,
15239 If the expression could be simplified to a constant, then return
15240 the constant. If the expression would not be simplified to a
15241 constant, then return NULL_TREE. */
15244 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15246 tree tem = fold_binary (code, type, op0, op1);
15247 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15250 /* Given the components of a unary expression CODE, TYPE and OP0,
15251 attempt to fold the expression to a constant without modifying
15254 If the expression could be simplified to a constant, then return
15255 the constant. If the expression would not be simplified to a
15256 constant, then return NULL_TREE. */
15259 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15261 tree tem = fold_unary (code, type, op0);
15262 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15265 /* If EXP represents referencing an element in a constant string
15266 (either via pointer arithmetic or array indexing), return the
15267 tree representing the value accessed, otherwise return NULL. */
15270 fold_read_from_constant_string (tree exp)
15272 if ((TREE_CODE (exp) == INDIRECT_REF
15273 || TREE_CODE (exp) == ARRAY_REF)
15274 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15276 tree exp1 = TREE_OPERAND (exp, 0);
15279 location_t loc = EXPR_LOCATION (exp);
15281 if (TREE_CODE (exp) == INDIRECT_REF)
15282 string = string_constant (exp1, &index);
15285 tree low_bound = array_ref_low_bound (exp);
15286 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15288 /* Optimize the special-case of a zero lower bound.
15290 We convert the low_bound to sizetype to avoid some problems
15291 with constant folding. (E.g. suppose the lower bound is 1,
15292 and its mode is QI. Without the conversion,l (ARRAY
15293 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15294 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15295 if (! integer_zerop (low_bound))
15296 index = size_diffop_loc (loc, index,
15297 fold_convert_loc (loc, sizetype, low_bound));
15303 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15304 && TREE_CODE (string) == STRING_CST
15305 && TREE_CODE (index) == INTEGER_CST
15306 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15307 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15309 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15310 return build_int_cst_type (TREE_TYPE (exp),
15311 (TREE_STRING_POINTER (string)
15312 [TREE_INT_CST_LOW (index)]));
15317 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15318 an integer constant, real, or fixed-point constant.
15320 TYPE is the type of the result. */
15323 fold_negate_const (tree arg0, tree type)
15325 tree t = NULL_TREE;
15327 switch (TREE_CODE (arg0))
15331 double_int val = tree_to_double_int (arg0);
15332 int overflow = neg_double (val.low, val.high, &val.low, &val.high);
15334 t = force_fit_type_double (type, val, 1,
15335 (overflow | TREE_OVERFLOW (arg0))
15336 && !TYPE_UNSIGNED (type));
15341 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15346 FIXED_VALUE_TYPE f;
15347 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15348 &(TREE_FIXED_CST (arg0)), NULL,
15349 TYPE_SATURATING (type));
15350 t = build_fixed (type, f);
15351 /* Propagate overflow flags. */
15352 if (overflow_p | TREE_OVERFLOW (arg0))
15353 TREE_OVERFLOW (t) = 1;
15358 gcc_unreachable ();
15364 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15365 an integer constant or real constant.
15367 TYPE is the type of the result. */
15370 fold_abs_const (tree arg0, tree type)
15372 tree t = NULL_TREE;
15374 switch (TREE_CODE (arg0))
15378 double_int val = tree_to_double_int (arg0);
15380 /* If the value is unsigned or non-negative, then the absolute value
15381 is the same as the ordinary value. */
15382 if (TYPE_UNSIGNED (type)
15383 || !double_int_negative_p (val))
15386 /* If the value is negative, then the absolute value is
15392 overflow = neg_double (val.low, val.high, &val.low, &val.high);
15393 t = force_fit_type_double (type, val, -1,
15394 overflow | TREE_OVERFLOW (arg0));
15400 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15401 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15407 gcc_unreachable ();
15413 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15414 constant. TYPE is the type of the result. */
15417 fold_not_const (const_tree arg0, tree type)
15421 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15423 val = double_int_not (tree_to_double_int (arg0));
15424 return force_fit_type_double (type, val, 0, TREE_OVERFLOW (arg0));
15427 /* Given CODE, a relational operator, the target type, TYPE and two
15428 constant operands OP0 and OP1, return the result of the
15429 relational operation. If the result is not a compile time
15430 constant, then return NULL_TREE. */
15433 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15435 int result, invert;
15437 /* From here on, the only cases we handle are when the result is
15438 known to be a constant. */
15440 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15442 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15443 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15445 /* Handle the cases where either operand is a NaN. */
15446 if (real_isnan (c0) || real_isnan (c1))
15456 case UNORDERED_EXPR:
15470 if (flag_trapping_math)
15476 gcc_unreachable ();
15479 return constant_boolean_node (result, type);
15482 return constant_boolean_node (real_compare (code, c0, c1), type);
15485 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15487 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15488 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15489 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15492 /* Handle equality/inequality of complex constants. */
15493 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15495 tree rcond = fold_relational_const (code, type,
15496 TREE_REALPART (op0),
15497 TREE_REALPART (op1));
15498 tree icond = fold_relational_const (code, type,
15499 TREE_IMAGPART (op0),
15500 TREE_IMAGPART (op1));
15501 if (code == EQ_EXPR)
15502 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15503 else if (code == NE_EXPR)
15504 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15509 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15511 To compute GT, swap the arguments and do LT.
15512 To compute GE, do LT and invert the result.
15513 To compute LE, swap the arguments, do LT and invert the result.
15514 To compute NE, do EQ and invert the result.
15516 Therefore, the code below must handle only EQ and LT. */
15518 if (code == LE_EXPR || code == GT_EXPR)
15523 code = swap_tree_comparison (code);
15526 /* Note that it is safe to invert for real values here because we
15527 have already handled the one case that it matters. */
15530 if (code == NE_EXPR || code == GE_EXPR)
15533 code = invert_tree_comparison (code, false);
15536 /* Compute a result for LT or EQ if args permit;
15537 Otherwise return T. */
15538 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15540 if (code == EQ_EXPR)
15541 result = tree_int_cst_equal (op0, op1);
15542 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15543 result = INT_CST_LT_UNSIGNED (op0, op1);
15545 result = INT_CST_LT (op0, op1);
15552 return constant_boolean_node (result, type);
15555 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15556 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15560 fold_build_cleanup_point_expr (tree type, tree expr)
15562 /* If the expression does not have side effects then we don't have to wrap
15563 it with a cleanup point expression. */
15564 if (!TREE_SIDE_EFFECTS (expr))
15567 /* If the expression is a return, check to see if the expression inside the
15568 return has no side effects or the right hand side of the modify expression
15569 inside the return. If either don't have side effects set we don't need to
15570 wrap the expression in a cleanup point expression. Note we don't check the
15571 left hand side of the modify because it should always be a return decl. */
15572 if (TREE_CODE (expr) == RETURN_EXPR)
15574 tree op = TREE_OPERAND (expr, 0);
15575 if (!op || !TREE_SIDE_EFFECTS (op))
15577 op = TREE_OPERAND (op, 1);
15578 if (!TREE_SIDE_EFFECTS (op))
15582 return build1 (CLEANUP_POINT_EXPR, type, expr);
15585 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15586 of an indirection through OP0, or NULL_TREE if no simplification is
15590 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
15596 subtype = TREE_TYPE (sub);
15597 if (!POINTER_TYPE_P (subtype))
15600 if (TREE_CODE (sub) == ADDR_EXPR)
15602 tree op = TREE_OPERAND (sub, 0);
15603 tree optype = TREE_TYPE (op);
15604 /* *&CONST_DECL -> to the value of the const decl. */
15605 if (TREE_CODE (op) == CONST_DECL)
15606 return DECL_INITIAL (op);
15607 /* *&p => p; make sure to handle *&"str"[cst] here. */
15608 if (type == optype)
15610 tree fop = fold_read_from_constant_string (op);
15616 /* *(foo *)&fooarray => fooarray[0] */
15617 else if (TREE_CODE (optype) == ARRAY_TYPE
15618 && type == TREE_TYPE (optype)
15619 && (!in_gimple_form
15620 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
15622 tree type_domain = TYPE_DOMAIN (optype);
15623 tree min_val = size_zero_node;
15624 if (type_domain && TYPE_MIN_VALUE (type_domain))
15625 min_val = TYPE_MIN_VALUE (type_domain);
15627 && TREE_CODE (min_val) != INTEGER_CST)
15629 return build4_loc (loc, ARRAY_REF, type, op, min_val,
15630 NULL_TREE, NULL_TREE);
15632 /* *(foo *)&complexfoo => __real__ complexfoo */
15633 else if (TREE_CODE (optype) == COMPLEX_TYPE
15634 && type == TREE_TYPE (optype))
15635 return fold_build1_loc (loc, REALPART_EXPR, type, op);
15636 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15637 else if (TREE_CODE (optype) == VECTOR_TYPE
15638 && type == TREE_TYPE (optype))
15640 tree part_width = TYPE_SIZE (type);
15641 tree index = bitsize_int (0);
15642 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
15646 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15647 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15649 tree op00 = TREE_OPERAND (sub, 0);
15650 tree op01 = TREE_OPERAND (sub, 1);
15653 if (TREE_CODE (op00) == ADDR_EXPR)
15656 op00 = TREE_OPERAND (op00, 0);
15657 op00type = TREE_TYPE (op00);
15659 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15660 if (TREE_CODE (op00type) == VECTOR_TYPE
15661 && type == TREE_TYPE (op00type))
15663 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15664 tree part_width = TYPE_SIZE (type);
15665 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15666 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15667 tree index = bitsize_int (indexi);
15669 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (op00type))
15670 return fold_build3_loc (loc,
15671 BIT_FIELD_REF, type, op00,
15672 part_width, index);
15675 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15676 else if (TREE_CODE (op00type) == COMPLEX_TYPE
15677 && type == TREE_TYPE (op00type))
15679 tree size = TYPE_SIZE_UNIT (type);
15680 if (tree_int_cst_equal (size, op01))
15681 return fold_build1_loc (loc, IMAGPART_EXPR, type, op00);
15683 /* ((foo *)&fooarray)[1] => fooarray[1] */
15684 else if (TREE_CODE (op00type) == ARRAY_TYPE
15685 && type == TREE_TYPE (op00type))
15687 tree type_domain = TYPE_DOMAIN (op00type);
15688 tree min_val = size_zero_node;
15689 if (type_domain && TYPE_MIN_VALUE (type_domain))
15690 min_val = TYPE_MIN_VALUE (type_domain);
15691 op01 = size_binop_loc (loc, EXACT_DIV_EXPR, op01,
15692 TYPE_SIZE_UNIT (type));
15693 op01 = size_binop_loc (loc, PLUS_EXPR, op01, min_val);
15694 return build4_loc (loc, ARRAY_REF, type, op00, op01,
15695 NULL_TREE, NULL_TREE);
15700 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15701 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15702 && type == TREE_TYPE (TREE_TYPE (subtype))
15703 && (!in_gimple_form
15704 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
15707 tree min_val = size_zero_node;
15708 sub = build_fold_indirect_ref_loc (loc, sub);
15709 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15710 if (type_domain && TYPE_MIN_VALUE (type_domain))
15711 min_val = TYPE_MIN_VALUE (type_domain);
15713 && TREE_CODE (min_val) != INTEGER_CST)
15715 return build4_loc (loc, ARRAY_REF, type, sub, min_val, NULL_TREE,
15722 /* Builds an expression for an indirection through T, simplifying some
15726 build_fold_indirect_ref_loc (location_t loc, tree t)
15728 tree type = TREE_TYPE (TREE_TYPE (t));
15729 tree sub = fold_indirect_ref_1 (loc, type, t);
15734 return build1_loc (loc, INDIRECT_REF, type, t);
15737 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15740 fold_indirect_ref_loc (location_t loc, tree t)
15742 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
15750 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15751 whose result is ignored. The type of the returned tree need not be
15752 the same as the original expression. */
15755 fold_ignored_result (tree t)
15757 if (!TREE_SIDE_EFFECTS (t))
15758 return integer_zero_node;
15761 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15764 t = TREE_OPERAND (t, 0);
15768 case tcc_comparison:
15769 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15770 t = TREE_OPERAND (t, 0);
15771 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15772 t = TREE_OPERAND (t, 1);
15777 case tcc_expression:
15778 switch (TREE_CODE (t))
15780 case COMPOUND_EXPR:
15781 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15783 t = TREE_OPERAND (t, 0);
15787 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15788 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15790 t = TREE_OPERAND (t, 0);
15803 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15804 This can only be applied to objects of a sizetype. */
15807 round_up_loc (location_t loc, tree value, int divisor)
15809 tree div = NULL_TREE;
15811 gcc_assert (divisor > 0);
15815 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15816 have to do anything. Only do this when we are not given a const,
15817 because in that case, this check is more expensive than just
15819 if (TREE_CODE (value) != INTEGER_CST)
15821 div = build_int_cst (TREE_TYPE (value), divisor);
15823 if (multiple_of_p (TREE_TYPE (value), value, div))
15827 /* If divisor is a power of two, simplify this to bit manipulation. */
15828 if (divisor == (divisor & -divisor))
15830 if (TREE_CODE (value) == INTEGER_CST)
15832 double_int val = tree_to_double_int (value);
15835 if ((val.low & (divisor - 1)) == 0)
15838 overflow_p = TREE_OVERFLOW (value);
15839 val.low &= ~(divisor - 1);
15840 val.low += divisor;
15848 return force_fit_type_double (TREE_TYPE (value), val,
15855 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15856 value = size_binop_loc (loc, PLUS_EXPR, value, t);
15857 t = build_int_cst (TREE_TYPE (value), -divisor);
15858 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15864 div = build_int_cst (TREE_TYPE (value), divisor);
15865 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
15866 value = size_binop_loc (loc, MULT_EXPR, value, div);
15872 /* Likewise, but round down. */
15875 round_down_loc (location_t loc, tree value, int divisor)
15877 tree div = NULL_TREE;
15879 gcc_assert (divisor > 0);
15883 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15884 have to do anything. Only do this when we are not given a const,
15885 because in that case, this check is more expensive than just
15887 if (TREE_CODE (value) != INTEGER_CST)
15889 div = build_int_cst (TREE_TYPE (value), divisor);
15891 if (multiple_of_p (TREE_TYPE (value), value, div))
15895 /* If divisor is a power of two, simplify this to bit manipulation. */
15896 if (divisor == (divisor & -divisor))
15900 t = build_int_cst (TREE_TYPE (value), -divisor);
15901 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15906 div = build_int_cst (TREE_TYPE (value), divisor);
15907 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
15908 value = size_binop_loc (loc, MULT_EXPR, value, div);
15914 /* Returns the pointer to the base of the object addressed by EXP and
15915 extracts the information about the offset of the access, storing it
15916 to PBITPOS and POFFSET. */
15919 split_address_to_core_and_offset (tree exp,
15920 HOST_WIDE_INT *pbitpos, tree *poffset)
15923 enum machine_mode mode;
15924 int unsignedp, volatilep;
15925 HOST_WIDE_INT bitsize;
15926 location_t loc = EXPR_LOCATION (exp);
15928 if (TREE_CODE (exp) == ADDR_EXPR)
15930 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15931 poffset, &mode, &unsignedp, &volatilep,
15933 core = build_fold_addr_expr_loc (loc, core);
15939 *poffset = NULL_TREE;
15945 /* Returns true if addresses of E1 and E2 differ by a constant, false
15946 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15949 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15952 HOST_WIDE_INT bitpos1, bitpos2;
15953 tree toffset1, toffset2, tdiff, type;
15955 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15956 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15958 if (bitpos1 % BITS_PER_UNIT != 0
15959 || bitpos2 % BITS_PER_UNIT != 0
15960 || !operand_equal_p (core1, core2, 0))
15963 if (toffset1 && toffset2)
15965 type = TREE_TYPE (toffset1);
15966 if (type != TREE_TYPE (toffset2))
15967 toffset2 = fold_convert (type, toffset2);
15969 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15970 if (!cst_and_fits_in_hwi (tdiff))
15973 *diff = int_cst_value (tdiff);
15975 else if (toffset1 || toffset2)
15977 /* If only one of the offsets is non-constant, the difference cannot
15984 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15988 /* Simplify the floating point expression EXP when the sign of the
15989 result is not significant. Return NULL_TREE if no simplification
15993 fold_strip_sign_ops (tree exp)
15996 location_t loc = EXPR_LOCATION (exp);
15998 switch (TREE_CODE (exp))
16002 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16003 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
16007 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
16009 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16010 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16011 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
16012 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
16013 arg0 ? arg0 : TREE_OPERAND (exp, 0),
16014 arg1 ? arg1 : TREE_OPERAND (exp, 1));
16017 case COMPOUND_EXPR:
16018 arg0 = TREE_OPERAND (exp, 0);
16019 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16021 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
16025 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16026 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
16028 return fold_build3_loc (loc,
16029 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
16030 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16031 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16036 const enum built_in_function fcode = builtin_mathfn_code (exp);
16039 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16040 /* Strip copysign function call, return the 1st argument. */
16041 arg0 = CALL_EXPR_ARG (exp, 0);
16042 arg1 = CALL_EXPR_ARG (exp, 1);
16043 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16046 /* Strip sign ops from the argument of "odd" math functions. */
16047 if (negate_mathfn_p (fcode))
16049 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16051 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);