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 /* (PTR +p B) +p A -> PTR +p (B + A) */
9579 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9582 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
9583 tree arg00 = TREE_OPERAND (arg0, 0);
9584 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
9585 arg01, fold_convert_loc (loc, sizetype, arg1));
9586 return fold_convert_loc (loc, type,
9587 fold_build2_loc (loc, POINTER_PLUS_EXPR,
9592 /* PTR_CST +p CST -> CST1 */
9593 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9594 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
9595 fold_convert_loc (loc, type, arg1));
9597 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9598 of the array. Loop optimizer sometimes produce this type of
9600 if (TREE_CODE (arg0) == ADDR_EXPR)
9602 tem = try_move_mult_to_index (loc, arg0,
9603 fold_convert_loc (loc, sizetype, arg1));
9605 return fold_convert_loc (loc, type, tem);
9611 /* A + (-B) -> A - B */
9612 if (TREE_CODE (arg1) == NEGATE_EXPR)
9613 return fold_build2_loc (loc, MINUS_EXPR, type,
9614 fold_convert_loc (loc, type, arg0),
9615 fold_convert_loc (loc, type,
9616 TREE_OPERAND (arg1, 0)));
9617 /* (-A) + B -> B - A */
9618 if (TREE_CODE (arg0) == NEGATE_EXPR
9619 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9620 return fold_build2_loc (loc, MINUS_EXPR, type,
9621 fold_convert_loc (loc, type, arg1),
9622 fold_convert_loc (loc, type,
9623 TREE_OPERAND (arg0, 0)));
9625 if (INTEGRAL_TYPE_P (type))
9627 /* Convert ~A + 1 to -A. */
9628 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9629 && integer_onep (arg1))
9630 return fold_build1_loc (loc, NEGATE_EXPR, type,
9631 fold_convert_loc (loc, type,
9632 TREE_OPERAND (arg0, 0)));
9635 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9636 && !TYPE_OVERFLOW_TRAPS (type))
9638 tree tem = TREE_OPERAND (arg0, 0);
9641 if (operand_equal_p (tem, arg1, 0))
9643 t1 = build_int_cst_type (type, -1);
9644 return omit_one_operand_loc (loc, type, t1, arg1);
9649 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9650 && !TYPE_OVERFLOW_TRAPS (type))
9652 tree tem = TREE_OPERAND (arg1, 0);
9655 if (operand_equal_p (arg0, tem, 0))
9657 t1 = build_int_cst_type (type, -1);
9658 return omit_one_operand_loc (loc, type, t1, arg0);
9662 /* X + (X / CST) * -CST is X % CST. */
9663 if (TREE_CODE (arg1) == MULT_EXPR
9664 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9665 && operand_equal_p (arg0,
9666 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9668 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9669 tree cst1 = TREE_OPERAND (arg1, 1);
9670 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
9672 if (sum && integer_zerop (sum))
9673 return fold_convert_loc (loc, type,
9674 fold_build2_loc (loc, TRUNC_MOD_EXPR,
9675 TREE_TYPE (arg0), arg0,
9680 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9681 same or one. Make sure type is not saturating.
9682 fold_plusminus_mult_expr will re-associate. */
9683 if ((TREE_CODE (arg0) == MULT_EXPR
9684 || TREE_CODE (arg1) == MULT_EXPR)
9685 && !TYPE_SATURATING (type)
9686 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9688 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
9693 if (! FLOAT_TYPE_P (type))
9695 if (integer_zerop (arg1))
9696 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9698 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9699 with a constant, and the two constants have no bits in common,
9700 we should treat this as a BIT_IOR_EXPR since this may produce more
9702 if (TREE_CODE (arg0) == BIT_AND_EXPR
9703 && TREE_CODE (arg1) == BIT_AND_EXPR
9704 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9705 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9706 && integer_zerop (const_binop (BIT_AND_EXPR,
9707 TREE_OPERAND (arg0, 1),
9708 TREE_OPERAND (arg1, 1))))
9710 code = BIT_IOR_EXPR;
9714 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9715 (plus (plus (mult) (mult)) (foo)) so that we can
9716 take advantage of the factoring cases below. */
9717 if (((TREE_CODE (arg0) == PLUS_EXPR
9718 || TREE_CODE (arg0) == MINUS_EXPR)
9719 && TREE_CODE (arg1) == MULT_EXPR)
9720 || ((TREE_CODE (arg1) == PLUS_EXPR
9721 || TREE_CODE (arg1) == MINUS_EXPR)
9722 && TREE_CODE (arg0) == MULT_EXPR))
9724 tree parg0, parg1, parg, marg;
9725 enum tree_code pcode;
9727 if (TREE_CODE (arg1) == MULT_EXPR)
9728 parg = arg0, marg = arg1;
9730 parg = arg1, marg = arg0;
9731 pcode = TREE_CODE (parg);
9732 parg0 = TREE_OPERAND (parg, 0);
9733 parg1 = TREE_OPERAND (parg, 1);
9737 if (TREE_CODE (parg0) == MULT_EXPR
9738 && TREE_CODE (parg1) != MULT_EXPR)
9739 return fold_build2_loc (loc, pcode, type,
9740 fold_build2_loc (loc, PLUS_EXPR, type,
9741 fold_convert_loc (loc, type,
9743 fold_convert_loc (loc, type,
9745 fold_convert_loc (loc, type, parg1));
9746 if (TREE_CODE (parg0) != MULT_EXPR
9747 && TREE_CODE (parg1) == MULT_EXPR)
9749 fold_build2_loc (loc, PLUS_EXPR, type,
9750 fold_convert_loc (loc, type, parg0),
9751 fold_build2_loc (loc, pcode, type,
9752 fold_convert_loc (loc, type, marg),
9753 fold_convert_loc (loc, type,
9759 /* See if ARG1 is zero and X + ARG1 reduces to X. */
9760 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
9761 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9763 /* Likewise if the operands are reversed. */
9764 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
9765 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9767 /* Convert X + -C into X - C. */
9768 if (TREE_CODE (arg1) == REAL_CST
9769 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
9771 tem = fold_negate_const (arg1, type);
9772 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
9773 return fold_build2_loc (loc, MINUS_EXPR, type,
9774 fold_convert_loc (loc, type, arg0),
9775 fold_convert_loc (loc, type, tem));
9778 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
9779 to __complex__ ( x, y ). This is not the same for SNaNs or
9780 if signed zeros are involved. */
9781 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
9782 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
9783 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
9785 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
9786 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
9787 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
9788 bool arg0rz = false, arg0iz = false;
9789 if ((arg0r && (arg0rz = real_zerop (arg0r)))
9790 || (arg0i && (arg0iz = real_zerop (arg0i))))
9792 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
9793 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
9794 if (arg0rz && arg1i && real_zerop (arg1i))
9796 tree rp = arg1r ? arg1r
9797 : build1 (REALPART_EXPR, rtype, arg1);
9798 tree ip = arg0i ? arg0i
9799 : build1 (IMAGPART_EXPR, rtype, arg0);
9800 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9802 else if (arg0iz && arg1r && real_zerop (arg1r))
9804 tree rp = arg0r ? arg0r
9805 : build1 (REALPART_EXPR, rtype, arg0);
9806 tree ip = arg1i ? arg1i
9807 : build1 (IMAGPART_EXPR, rtype, arg1);
9808 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9813 if (flag_unsafe_math_optimizations
9814 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
9815 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
9816 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
9819 /* Convert x+x into x*2.0. */
9820 if (operand_equal_p (arg0, arg1, 0)
9821 && SCALAR_FLOAT_TYPE_P (type))
9822 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
9823 build_real (type, dconst2));
9825 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
9826 We associate floats only if the user has specified
9827 -fassociative-math. */
9828 if (flag_associative_math
9829 && TREE_CODE (arg1) == PLUS_EXPR
9830 && TREE_CODE (arg0) != MULT_EXPR)
9832 tree tree10 = TREE_OPERAND (arg1, 0);
9833 tree tree11 = TREE_OPERAND (arg1, 1);
9834 if (TREE_CODE (tree11) == MULT_EXPR
9835 && TREE_CODE (tree10) == MULT_EXPR)
9838 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
9839 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
9842 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
9843 We associate floats only if the user has specified
9844 -fassociative-math. */
9845 if (flag_associative_math
9846 && TREE_CODE (arg0) == PLUS_EXPR
9847 && TREE_CODE (arg1) != MULT_EXPR)
9849 tree tree00 = TREE_OPERAND (arg0, 0);
9850 tree tree01 = TREE_OPERAND (arg0, 1);
9851 if (TREE_CODE (tree01) == MULT_EXPR
9852 && TREE_CODE (tree00) == MULT_EXPR)
9855 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
9856 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
9862 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
9863 is a rotate of A by C1 bits. */
9864 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
9865 is a rotate of A by B bits. */
9867 enum tree_code code0, code1;
9869 code0 = TREE_CODE (arg0);
9870 code1 = TREE_CODE (arg1);
9871 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
9872 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
9873 && operand_equal_p (TREE_OPERAND (arg0, 0),
9874 TREE_OPERAND (arg1, 0), 0)
9875 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
9876 TYPE_UNSIGNED (rtype))
9877 /* Only create rotates in complete modes. Other cases are not
9878 expanded properly. */
9879 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
9881 tree tree01, tree11;
9882 enum tree_code code01, code11;
9884 tree01 = TREE_OPERAND (arg0, 1);
9885 tree11 = TREE_OPERAND (arg1, 1);
9886 STRIP_NOPS (tree01);
9887 STRIP_NOPS (tree11);
9888 code01 = TREE_CODE (tree01);
9889 code11 = TREE_CODE (tree11);
9890 if (code01 == INTEGER_CST
9891 && code11 == INTEGER_CST
9892 && TREE_INT_CST_HIGH (tree01) == 0
9893 && TREE_INT_CST_HIGH (tree11) == 0
9894 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
9895 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
9897 tem = build2_loc (loc, LROTATE_EXPR,
9898 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9899 TREE_OPERAND (arg0, 0),
9900 code0 == LSHIFT_EXPR ? tree01 : tree11);
9901 return fold_convert_loc (loc, type, tem);
9903 else if (code11 == MINUS_EXPR)
9905 tree tree110, tree111;
9906 tree110 = TREE_OPERAND (tree11, 0);
9907 tree111 = TREE_OPERAND (tree11, 1);
9908 STRIP_NOPS (tree110);
9909 STRIP_NOPS (tree111);
9910 if (TREE_CODE (tree110) == INTEGER_CST
9911 && 0 == compare_tree_int (tree110,
9913 (TREE_TYPE (TREE_OPERAND
9915 && operand_equal_p (tree01, tree111, 0))
9917 fold_convert_loc (loc, type,
9918 build2 ((code0 == LSHIFT_EXPR
9921 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9922 TREE_OPERAND (arg0, 0), tree01));
9924 else if (code01 == MINUS_EXPR)
9926 tree tree010, tree011;
9927 tree010 = TREE_OPERAND (tree01, 0);
9928 tree011 = TREE_OPERAND (tree01, 1);
9929 STRIP_NOPS (tree010);
9930 STRIP_NOPS (tree011);
9931 if (TREE_CODE (tree010) == INTEGER_CST
9932 && 0 == compare_tree_int (tree010,
9934 (TREE_TYPE (TREE_OPERAND
9936 && operand_equal_p (tree11, tree011, 0))
9937 return fold_convert_loc
9939 build2 ((code0 != LSHIFT_EXPR
9942 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9943 TREE_OPERAND (arg0, 0), tree11));
9949 /* In most languages, can't associate operations on floats through
9950 parentheses. Rather than remember where the parentheses were, we
9951 don't associate floats at all, unless the user has specified
9953 And, we need to make sure type is not saturating. */
9955 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
9956 && !TYPE_SATURATING (type))
9958 tree var0, con0, lit0, minus_lit0;
9959 tree var1, con1, lit1, minus_lit1;
9962 /* Split both trees into variables, constants, and literals. Then
9963 associate each group together, the constants with literals,
9964 then the result with variables. This increases the chances of
9965 literals being recombined later and of generating relocatable
9966 expressions for the sum of a constant and literal. */
9967 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
9968 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
9969 code == MINUS_EXPR);
9971 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
9972 if (code == MINUS_EXPR)
9975 /* With undefined overflow we can only associate constants with one
9976 variable, and constants whose association doesn't overflow. */
9977 if ((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
9978 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
9985 if (TREE_CODE (tmp0) == NEGATE_EXPR)
9986 tmp0 = TREE_OPERAND (tmp0, 0);
9987 if (TREE_CODE (tmp1) == NEGATE_EXPR)
9988 tmp1 = TREE_OPERAND (tmp1, 0);
9989 /* The only case we can still associate with two variables
9990 is if they are the same, modulo negation. */
9991 if (!operand_equal_p (tmp0, tmp1, 0))
9995 if (ok && lit0 && lit1)
9997 tree tmp0 = fold_convert (type, lit0);
9998 tree tmp1 = fold_convert (type, lit1);
10000 if (!TREE_OVERFLOW (tmp0) && !TREE_OVERFLOW (tmp1)
10001 && TREE_OVERFLOW (fold_build2 (code, type, tmp0, tmp1)))
10006 /* Only do something if we found more than two objects. Otherwise,
10007 nothing has changed and we risk infinite recursion. */
10009 && (2 < ((var0 != 0) + (var1 != 0)
10010 + (con0 != 0) + (con1 != 0)
10011 + (lit0 != 0) + (lit1 != 0)
10012 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10014 var0 = associate_trees (loc, var0, var1, code, type);
10015 con0 = associate_trees (loc, con0, con1, code, type);
10016 lit0 = associate_trees (loc, lit0, lit1, code, type);
10017 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10019 /* Preserve the MINUS_EXPR if the negative part of the literal is
10020 greater than the positive part. Otherwise, the multiplicative
10021 folding code (i.e extract_muldiv) may be fooled in case
10022 unsigned constants are subtracted, like in the following
10023 example: ((X*2 + 4) - 8U)/2. */
10024 if (minus_lit0 && lit0)
10026 if (TREE_CODE (lit0) == INTEGER_CST
10027 && TREE_CODE (minus_lit0) == INTEGER_CST
10028 && tree_int_cst_lt (lit0, minus_lit0))
10030 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10036 lit0 = associate_trees (loc, lit0, minus_lit0,
10045 fold_convert_loc (loc, type,
10046 associate_trees (loc, var0, minus_lit0,
10047 MINUS_EXPR, type));
10050 con0 = associate_trees (loc, con0, minus_lit0,
10053 fold_convert_loc (loc, type,
10054 associate_trees (loc, var0, con0,
10059 con0 = associate_trees (loc, con0, lit0, code, type);
10061 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10069 /* Pointer simplifications for subtraction, simple reassociations. */
10070 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10072 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10073 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10074 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10076 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10077 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10078 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10079 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10080 return fold_build2_loc (loc, PLUS_EXPR, type,
10081 fold_build2_loc (loc, MINUS_EXPR, type,
10083 fold_build2_loc (loc, MINUS_EXPR, type,
10086 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10087 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10089 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10090 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10091 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10092 fold_convert_loc (loc, type, arg1));
10094 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10097 /* A - (-B) -> A + B */
10098 if (TREE_CODE (arg1) == NEGATE_EXPR)
10099 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10100 fold_convert_loc (loc, type,
10101 TREE_OPERAND (arg1, 0)));
10102 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10103 if (TREE_CODE (arg0) == NEGATE_EXPR
10104 && (FLOAT_TYPE_P (type)
10105 || INTEGRAL_TYPE_P (type))
10106 && negate_expr_p (arg1)
10107 && reorder_operands_p (arg0, arg1))
10108 return fold_build2_loc (loc, MINUS_EXPR, type,
10109 fold_convert_loc (loc, type,
10110 negate_expr (arg1)),
10111 fold_convert_loc (loc, type,
10112 TREE_OPERAND (arg0, 0)));
10113 /* Convert -A - 1 to ~A. */
10114 if (INTEGRAL_TYPE_P (type)
10115 && TREE_CODE (arg0) == NEGATE_EXPR
10116 && integer_onep (arg1)
10117 && !TYPE_OVERFLOW_TRAPS (type))
10118 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10119 fold_convert_loc (loc, type,
10120 TREE_OPERAND (arg0, 0)));
10122 /* Convert -1 - A to ~A. */
10123 if (INTEGRAL_TYPE_P (type)
10124 && integer_all_onesp (arg0))
10125 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10128 /* X - (X / CST) * CST is X % CST. */
10129 if (INTEGRAL_TYPE_P (type)
10130 && TREE_CODE (arg1) == MULT_EXPR
10131 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10132 && operand_equal_p (arg0,
10133 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10134 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10135 TREE_OPERAND (arg1, 1), 0))
10137 fold_convert_loc (loc, type,
10138 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10139 arg0, TREE_OPERAND (arg1, 1)));
10141 if (! FLOAT_TYPE_P (type))
10143 if (integer_zerop (arg0))
10144 return negate_expr (fold_convert_loc (loc, type, arg1));
10145 if (integer_zerop (arg1))
10146 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10148 /* Fold A - (A & B) into ~B & A. */
10149 if (!TREE_SIDE_EFFECTS (arg0)
10150 && TREE_CODE (arg1) == BIT_AND_EXPR)
10152 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10154 tree arg10 = fold_convert_loc (loc, type,
10155 TREE_OPERAND (arg1, 0));
10156 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10157 fold_build1_loc (loc, BIT_NOT_EXPR,
10159 fold_convert_loc (loc, type, arg0));
10161 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10163 tree arg11 = fold_convert_loc (loc,
10164 type, TREE_OPERAND (arg1, 1));
10165 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10166 fold_build1_loc (loc, BIT_NOT_EXPR,
10168 fold_convert_loc (loc, type, arg0));
10172 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10173 any power of 2 minus 1. */
10174 if (TREE_CODE (arg0) == BIT_AND_EXPR
10175 && TREE_CODE (arg1) == BIT_AND_EXPR
10176 && operand_equal_p (TREE_OPERAND (arg0, 0),
10177 TREE_OPERAND (arg1, 0), 0))
10179 tree mask0 = TREE_OPERAND (arg0, 1);
10180 tree mask1 = TREE_OPERAND (arg1, 1);
10181 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10183 if (operand_equal_p (tem, mask1, 0))
10185 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10186 TREE_OPERAND (arg0, 0), mask1);
10187 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10192 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10193 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10194 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10196 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10197 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10198 (-ARG1 + ARG0) reduces to -ARG1. */
10199 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10200 return negate_expr (fold_convert_loc (loc, type, arg1));
10202 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10203 __complex__ ( x, -y ). This is not the same for SNaNs or if
10204 signed zeros are involved. */
10205 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10206 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10207 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10209 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10210 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10211 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10212 bool arg0rz = false, arg0iz = false;
10213 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10214 || (arg0i && (arg0iz = real_zerop (arg0i))))
10216 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10217 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10218 if (arg0rz && arg1i && real_zerop (arg1i))
10220 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10222 : build1 (REALPART_EXPR, rtype, arg1));
10223 tree ip = arg0i ? arg0i
10224 : build1 (IMAGPART_EXPR, rtype, arg0);
10225 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10227 else if (arg0iz && arg1r && real_zerop (arg1r))
10229 tree rp = arg0r ? arg0r
10230 : build1 (REALPART_EXPR, rtype, arg0);
10231 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10233 : build1 (IMAGPART_EXPR, rtype, arg1));
10234 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10239 /* Fold &x - &x. This can happen from &x.foo - &x.
10240 This is unsafe for certain floats even in non-IEEE formats.
10241 In IEEE, it is unsafe because it does wrong for NaNs.
10242 Also note that operand_equal_p is always false if an operand
10245 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10246 && operand_equal_p (arg0, arg1, 0))
10247 return build_zero_cst (type);
10249 /* A - B -> A + (-B) if B is easily negatable. */
10250 if (negate_expr_p (arg1)
10251 && ((FLOAT_TYPE_P (type)
10252 /* Avoid this transformation if B is a positive REAL_CST. */
10253 && (TREE_CODE (arg1) != REAL_CST
10254 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10255 || INTEGRAL_TYPE_P (type)))
10256 return fold_build2_loc (loc, PLUS_EXPR, type,
10257 fold_convert_loc (loc, type, arg0),
10258 fold_convert_loc (loc, type,
10259 negate_expr (arg1)));
10261 /* Try folding difference of addresses. */
10263 HOST_WIDE_INT diff;
10265 if ((TREE_CODE (arg0) == ADDR_EXPR
10266 || TREE_CODE (arg1) == ADDR_EXPR)
10267 && ptr_difference_const (arg0, arg1, &diff))
10268 return build_int_cst_type (type, diff);
10271 /* Fold &a[i] - &a[j] to i-j. */
10272 if (TREE_CODE (arg0) == ADDR_EXPR
10273 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10274 && TREE_CODE (arg1) == ADDR_EXPR
10275 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10277 tree aref0 = TREE_OPERAND (arg0, 0);
10278 tree aref1 = TREE_OPERAND (arg1, 0);
10279 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10280 TREE_OPERAND (aref1, 0), 0))
10282 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
10283 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
10284 tree esz = array_ref_element_size (aref0);
10285 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10286 return fold_build2_loc (loc, MULT_EXPR, type, diff,
10287 fold_convert_loc (loc, type, esz));
10292 if (FLOAT_TYPE_P (type)
10293 && flag_unsafe_math_optimizations
10294 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10295 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10296 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10299 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10300 same or one. Make sure type is not saturating.
10301 fold_plusminus_mult_expr will re-associate. */
10302 if ((TREE_CODE (arg0) == MULT_EXPR
10303 || TREE_CODE (arg1) == MULT_EXPR)
10304 && !TYPE_SATURATING (type)
10305 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10307 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10315 /* (-A) * (-B) -> A * B */
10316 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10317 return fold_build2_loc (loc, MULT_EXPR, type,
10318 fold_convert_loc (loc, type,
10319 TREE_OPERAND (arg0, 0)),
10320 fold_convert_loc (loc, type,
10321 negate_expr (arg1)));
10322 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10323 return fold_build2_loc (loc, MULT_EXPR, type,
10324 fold_convert_loc (loc, type,
10325 negate_expr (arg0)),
10326 fold_convert_loc (loc, type,
10327 TREE_OPERAND (arg1, 0)));
10329 if (! FLOAT_TYPE_P (type))
10331 if (integer_zerop (arg1))
10332 return omit_one_operand_loc (loc, type, arg1, arg0);
10333 if (integer_onep (arg1))
10334 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10335 /* Transform x * -1 into -x. Make sure to do the negation
10336 on the original operand with conversions not stripped
10337 because we can only strip non-sign-changing conversions. */
10338 if (integer_all_onesp (arg1))
10339 return fold_convert_loc (loc, type, negate_expr (op0));
10340 /* Transform x * -C into -x * C if x is easily negatable. */
10341 if (TREE_CODE (arg1) == INTEGER_CST
10342 && tree_int_cst_sgn (arg1) == -1
10343 && negate_expr_p (arg0)
10344 && (tem = negate_expr (arg1)) != arg1
10345 && !TREE_OVERFLOW (tem))
10346 return fold_build2_loc (loc, MULT_EXPR, type,
10347 fold_convert_loc (loc, type,
10348 negate_expr (arg0)),
10351 /* (a * (1 << b)) is (a << b) */
10352 if (TREE_CODE (arg1) == LSHIFT_EXPR
10353 && integer_onep (TREE_OPERAND (arg1, 0)))
10354 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
10355 TREE_OPERAND (arg1, 1));
10356 if (TREE_CODE (arg0) == LSHIFT_EXPR
10357 && integer_onep (TREE_OPERAND (arg0, 0)))
10358 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
10359 TREE_OPERAND (arg0, 1));
10361 /* (A + A) * C -> A * 2 * C */
10362 if (TREE_CODE (arg0) == PLUS_EXPR
10363 && TREE_CODE (arg1) == INTEGER_CST
10364 && operand_equal_p (TREE_OPERAND (arg0, 0),
10365 TREE_OPERAND (arg0, 1), 0))
10366 return fold_build2_loc (loc, MULT_EXPR, type,
10367 omit_one_operand_loc (loc, type,
10368 TREE_OPERAND (arg0, 0),
10369 TREE_OPERAND (arg0, 1)),
10370 fold_build2_loc (loc, MULT_EXPR, type,
10371 build_int_cst (type, 2) , arg1));
10373 strict_overflow_p = false;
10374 if (TREE_CODE (arg1) == INTEGER_CST
10375 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10376 &strict_overflow_p)))
10378 if (strict_overflow_p)
10379 fold_overflow_warning (("assuming signed overflow does not "
10380 "occur when simplifying "
10382 WARN_STRICT_OVERFLOW_MISC);
10383 return fold_convert_loc (loc, type, tem);
10386 /* Optimize z * conj(z) for integer complex numbers. */
10387 if (TREE_CODE (arg0) == CONJ_EXPR
10388 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10389 return fold_mult_zconjz (loc, type, arg1);
10390 if (TREE_CODE (arg1) == CONJ_EXPR
10391 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10392 return fold_mult_zconjz (loc, type, arg0);
10396 /* Maybe fold x * 0 to 0. The expressions aren't the same
10397 when x is NaN, since x * 0 is also NaN. Nor are they the
10398 same in modes with signed zeros, since multiplying a
10399 negative value by 0 gives -0, not +0. */
10400 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10401 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10402 && real_zerop (arg1))
10403 return omit_one_operand_loc (loc, type, arg1, arg0);
10404 /* In IEEE floating point, x*1 is not equivalent to x for snans.
10405 Likewise for complex arithmetic with signed zeros. */
10406 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10407 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10408 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10409 && real_onep (arg1))
10410 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10412 /* Transform x * -1.0 into -x. */
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_minus_onep (arg1))
10417 return fold_convert_loc (loc, type, negate_expr (arg0));
10419 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10420 the result for floating point types due to rounding so it is applied
10421 only if -fassociative-math was specify. */
10422 if (flag_associative_math
10423 && TREE_CODE (arg0) == RDIV_EXPR
10424 && TREE_CODE (arg1) == REAL_CST
10425 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10427 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10430 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
10431 TREE_OPERAND (arg0, 1));
10434 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10435 if (operand_equal_p (arg0, arg1, 0))
10437 tree tem = fold_strip_sign_ops (arg0);
10438 if (tem != NULL_TREE)
10440 tem = fold_convert_loc (loc, type, tem);
10441 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
10445 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10446 This is not the same for NaNs or if signed zeros are
10448 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10449 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10450 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10451 && TREE_CODE (arg1) == COMPLEX_CST
10452 && real_zerop (TREE_REALPART (arg1)))
10454 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10455 if (real_onep (TREE_IMAGPART (arg1)))
10457 fold_build2_loc (loc, COMPLEX_EXPR, type,
10458 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
10460 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
10461 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10463 fold_build2_loc (loc, COMPLEX_EXPR, type,
10464 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
10465 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
10469 /* Optimize z * conj(z) for floating point complex numbers.
10470 Guarded by flag_unsafe_math_optimizations as non-finite
10471 imaginary components don't produce scalar results. */
10472 if (flag_unsafe_math_optimizations
10473 && TREE_CODE (arg0) == CONJ_EXPR
10474 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10475 return fold_mult_zconjz (loc, type, arg1);
10476 if (flag_unsafe_math_optimizations
10477 && TREE_CODE (arg1) == CONJ_EXPR
10478 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10479 return fold_mult_zconjz (loc, type, arg0);
10481 if (flag_unsafe_math_optimizations)
10483 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10484 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10486 /* Optimizations of root(...)*root(...). */
10487 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10490 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10491 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10493 /* Optimize sqrt(x)*sqrt(x) as x. */
10494 if (BUILTIN_SQRT_P (fcode0)
10495 && operand_equal_p (arg00, arg10, 0)
10496 && ! HONOR_SNANS (TYPE_MODE (type)))
10499 /* Optimize root(x)*root(y) as root(x*y). */
10500 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10501 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
10502 return build_call_expr_loc (loc, rootfn, 1, arg);
10505 /* Optimize expN(x)*expN(y) as expN(x+y). */
10506 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10508 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10509 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10510 CALL_EXPR_ARG (arg0, 0),
10511 CALL_EXPR_ARG (arg1, 0));
10512 return build_call_expr_loc (loc, expfn, 1, arg);
10515 /* Optimizations of pow(...)*pow(...). */
10516 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10517 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10518 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10520 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10521 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10522 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10523 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10525 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10526 if (operand_equal_p (arg01, arg11, 0))
10528 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10529 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
10531 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
10534 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10535 if (operand_equal_p (arg00, arg10, 0))
10537 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10538 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10540 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
10544 /* Optimize tan(x)*cos(x) as sin(x). */
10545 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10546 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10547 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10548 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10549 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10550 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10551 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10552 CALL_EXPR_ARG (arg1, 0), 0))
10554 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10556 if (sinfn != NULL_TREE)
10557 return build_call_expr_loc (loc, sinfn, 1,
10558 CALL_EXPR_ARG (arg0, 0));
10561 /* Optimize x*pow(x,c) as pow(x,c+1). */
10562 if (fcode1 == BUILT_IN_POW
10563 || fcode1 == BUILT_IN_POWF
10564 || fcode1 == BUILT_IN_POWL)
10566 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10567 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10568 if (TREE_CODE (arg11) == REAL_CST
10569 && !TREE_OVERFLOW (arg11)
10570 && operand_equal_p (arg0, arg10, 0))
10572 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10576 c = TREE_REAL_CST (arg11);
10577 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10578 arg = build_real (type, c);
10579 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10583 /* Optimize pow(x,c)*x as pow(x,c+1). */
10584 if (fcode0 == BUILT_IN_POW
10585 || fcode0 == BUILT_IN_POWF
10586 || fcode0 == BUILT_IN_POWL)
10588 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10589 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10590 if (TREE_CODE (arg01) == REAL_CST
10591 && !TREE_OVERFLOW (arg01)
10592 && operand_equal_p (arg1, arg00, 0))
10594 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10598 c = TREE_REAL_CST (arg01);
10599 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10600 arg = build_real (type, c);
10601 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
10605 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10606 if (!in_gimple_form
10607 && optimize_function_for_speed_p (cfun)
10608 && operand_equal_p (arg0, arg1, 0))
10610 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10614 tree arg = build_real (type, dconst2);
10615 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10624 if (integer_all_onesp (arg1))
10625 return omit_one_operand_loc (loc, type, arg1, arg0);
10626 if (integer_zerop (arg1))
10627 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10628 if (operand_equal_p (arg0, arg1, 0))
10629 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10631 /* ~X | X is -1. */
10632 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10633 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10635 t1 = build_zero_cst (type);
10636 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10637 return omit_one_operand_loc (loc, type, t1, arg1);
10640 /* X | ~X is -1. */
10641 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10642 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10644 t1 = build_zero_cst (type);
10645 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10646 return omit_one_operand_loc (loc, type, t1, arg0);
10649 /* Canonicalize (X & C1) | C2. */
10650 if (TREE_CODE (arg0) == BIT_AND_EXPR
10651 && TREE_CODE (arg1) == INTEGER_CST
10652 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10654 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10655 int width = TYPE_PRECISION (type), w;
10656 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10657 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10658 hi2 = TREE_INT_CST_HIGH (arg1);
10659 lo2 = TREE_INT_CST_LOW (arg1);
10661 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10662 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10663 return omit_one_operand_loc (loc, type, arg1,
10664 TREE_OPERAND (arg0, 0));
10666 if (width > HOST_BITS_PER_WIDE_INT)
10668 mhi = (unsigned HOST_WIDE_INT) -1
10669 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10675 mlo = (unsigned HOST_WIDE_INT) -1
10676 >> (HOST_BITS_PER_WIDE_INT - width);
10679 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10680 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10681 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10682 TREE_OPERAND (arg0, 0), arg1);
10684 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10685 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10686 mode which allows further optimizations. */
10693 for (w = BITS_PER_UNIT;
10694 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10697 unsigned HOST_WIDE_INT mask
10698 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10699 if (((lo1 | lo2) & mask) == mask
10700 && (lo1 & ~mask) == 0 && hi1 == 0)
10707 if (hi3 != hi1 || lo3 != lo1)
10708 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10709 fold_build2_loc (loc, BIT_AND_EXPR, type,
10710 TREE_OPERAND (arg0, 0),
10711 build_int_cst_wide (type,
10716 /* (X & Y) | Y is (X, Y). */
10717 if (TREE_CODE (arg0) == BIT_AND_EXPR
10718 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10719 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10720 /* (X & Y) | X is (Y, X). */
10721 if (TREE_CODE (arg0) == BIT_AND_EXPR
10722 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10723 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10724 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
10725 /* X | (X & Y) is (Y, X). */
10726 if (TREE_CODE (arg1) == BIT_AND_EXPR
10727 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10728 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10729 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
10730 /* X | (Y & X) is (Y, X). */
10731 if (TREE_CODE (arg1) == BIT_AND_EXPR
10732 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10733 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10734 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
10736 /* (X & ~Y) | (~X & Y) is X ^ Y */
10737 if (TREE_CODE (arg0) == BIT_AND_EXPR
10738 && TREE_CODE (arg1) == BIT_AND_EXPR)
10740 tree a0, a1, l0, l1, n0, n1;
10742 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10743 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10745 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10746 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10748 n0 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l0);
10749 n1 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l1);
10751 if ((operand_equal_p (n0, a0, 0)
10752 && operand_equal_p (n1, a1, 0))
10753 || (operand_equal_p (n0, a1, 0)
10754 && operand_equal_p (n1, a0, 0)))
10755 return fold_build2_loc (loc, BIT_XOR_EXPR, type, l0, n1);
10758 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
10759 if (t1 != NULL_TREE)
10762 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10764 This results in more efficient code for machines without a NAND
10765 instruction. Combine will canonicalize to the first form
10766 which will allow use of NAND instructions provided by the
10767 backend if they exist. */
10768 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10769 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10772 fold_build1_loc (loc, BIT_NOT_EXPR, type,
10773 build2 (BIT_AND_EXPR, type,
10774 fold_convert_loc (loc, type,
10775 TREE_OPERAND (arg0, 0)),
10776 fold_convert_loc (loc, type,
10777 TREE_OPERAND (arg1, 0))));
10780 /* See if this can be simplified into a rotate first. If that
10781 is unsuccessful continue in the association code. */
10785 if (integer_zerop (arg1))
10786 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10787 if (integer_all_onesp (arg1))
10788 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
10789 if (operand_equal_p (arg0, arg1, 0))
10790 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10792 /* ~X ^ X is -1. */
10793 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10794 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10796 t1 = build_zero_cst (type);
10797 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10798 return omit_one_operand_loc (loc, type, t1, arg1);
10801 /* X ^ ~X is -1. */
10802 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10803 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10805 t1 = build_zero_cst (type);
10806 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10807 return omit_one_operand_loc (loc, type, t1, arg0);
10810 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10811 with a constant, and the two constants have no bits in common,
10812 we should treat this as a BIT_IOR_EXPR since this may produce more
10813 simplifications. */
10814 if (TREE_CODE (arg0) == BIT_AND_EXPR
10815 && TREE_CODE (arg1) == BIT_AND_EXPR
10816 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10817 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10818 && integer_zerop (const_binop (BIT_AND_EXPR,
10819 TREE_OPERAND (arg0, 1),
10820 TREE_OPERAND (arg1, 1))))
10822 code = BIT_IOR_EXPR;
10826 /* (X | Y) ^ X -> Y & ~ X*/
10827 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10828 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10830 tree t2 = TREE_OPERAND (arg0, 1);
10831 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10833 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10834 fold_convert_loc (loc, type, t2),
10835 fold_convert_loc (loc, type, t1));
10839 /* (Y | X) ^ X -> Y & ~ X*/
10840 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10841 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10843 tree t2 = TREE_OPERAND (arg0, 0);
10844 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10846 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10847 fold_convert_loc (loc, type, t2),
10848 fold_convert_loc (loc, type, t1));
10852 /* X ^ (X | Y) -> Y & ~ X*/
10853 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10854 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
10856 tree t2 = TREE_OPERAND (arg1, 1);
10857 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10859 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10860 fold_convert_loc (loc, type, t2),
10861 fold_convert_loc (loc, type, t1));
10865 /* X ^ (Y | X) -> Y & ~ X*/
10866 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10867 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
10869 tree t2 = TREE_OPERAND (arg1, 0);
10870 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10872 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10873 fold_convert_loc (loc, type, t2),
10874 fold_convert_loc (loc, type, t1));
10878 /* Convert ~X ^ ~Y to X ^ Y. */
10879 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10880 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10881 return fold_build2_loc (loc, code, type,
10882 fold_convert_loc (loc, type,
10883 TREE_OPERAND (arg0, 0)),
10884 fold_convert_loc (loc, type,
10885 TREE_OPERAND (arg1, 0)));
10887 /* Convert ~X ^ C to X ^ ~C. */
10888 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10889 && TREE_CODE (arg1) == INTEGER_CST)
10890 return fold_build2_loc (loc, code, type,
10891 fold_convert_loc (loc, type,
10892 TREE_OPERAND (arg0, 0)),
10893 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
10895 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
10896 if (TREE_CODE (arg0) == BIT_AND_EXPR
10897 && integer_onep (TREE_OPERAND (arg0, 1))
10898 && integer_onep (arg1))
10899 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
10900 build_int_cst (TREE_TYPE (arg0), 0));
10902 /* Fold (X & Y) ^ Y as ~X & Y. */
10903 if (TREE_CODE (arg0) == BIT_AND_EXPR
10904 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10906 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10907 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10908 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10909 fold_convert_loc (loc, type, arg1));
10911 /* Fold (X & Y) ^ X as ~Y & X. */
10912 if (TREE_CODE (arg0) == BIT_AND_EXPR
10913 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10914 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10916 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10917 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10918 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10919 fold_convert_loc (loc, type, arg1));
10921 /* Fold X ^ (X & Y) as X & ~Y. */
10922 if (TREE_CODE (arg1) == BIT_AND_EXPR
10923 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10925 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10926 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10927 fold_convert_loc (loc, type, arg0),
10928 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
10930 /* Fold X ^ (Y & X) as ~Y & X. */
10931 if (TREE_CODE (arg1) == BIT_AND_EXPR
10932 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10933 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10935 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10936 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10937 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10938 fold_convert_loc (loc, type, arg0));
10941 /* See if this can be simplified into a rotate first. If that
10942 is unsuccessful continue in the association code. */
10946 if (integer_all_onesp (arg1))
10947 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10948 if (integer_zerop (arg1))
10949 return omit_one_operand_loc (loc, type, arg1, arg0);
10950 if (operand_equal_p (arg0, arg1, 0))
10951 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10953 /* ~X & X, (X == 0) & X, and !X & X are always zero. */
10954 if ((TREE_CODE (arg0) == BIT_NOT_EXPR
10955 || TREE_CODE (arg0) == TRUTH_NOT_EXPR
10956 || (TREE_CODE (arg0) == EQ_EXPR
10957 && integer_zerop (TREE_OPERAND (arg0, 1))))
10958 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10959 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
10961 /* X & ~X , X & (X == 0), and X & !X are always zero. */
10962 if ((TREE_CODE (arg1) == BIT_NOT_EXPR
10963 || TREE_CODE (arg1) == TRUTH_NOT_EXPR
10964 || (TREE_CODE (arg1) == EQ_EXPR
10965 && integer_zerop (TREE_OPERAND (arg1, 1))))
10966 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10967 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10969 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
10970 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10971 && TREE_CODE (arg1) == INTEGER_CST
10972 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10974 tree tmp1 = fold_convert_loc (loc, type, arg1);
10975 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10976 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10977 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
10978 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
10980 fold_convert_loc (loc, type,
10981 fold_build2_loc (loc, BIT_IOR_EXPR,
10982 type, tmp2, tmp3));
10985 /* (X | Y) & Y is (X, Y). */
10986 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10987 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10988 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10989 /* (X | Y) & X is (Y, X). */
10990 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10991 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10992 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10993 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
10994 /* X & (X | Y) is (Y, X). */
10995 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10996 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10997 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10998 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
10999 /* X & (Y | X) is (Y, X). */
11000 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11001 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11002 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11003 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11005 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11006 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11007 && integer_onep (TREE_OPERAND (arg0, 1))
11008 && integer_onep (arg1))
11010 tem = TREE_OPERAND (arg0, 0);
11011 return fold_build2_loc (loc, EQ_EXPR, type,
11012 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11013 build_int_cst (TREE_TYPE (tem), 1)),
11014 build_int_cst (TREE_TYPE (tem), 0));
11016 /* Fold ~X & 1 as (X & 1) == 0. */
11017 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11018 && integer_onep (arg1))
11020 tem = TREE_OPERAND (arg0, 0);
11021 return fold_build2_loc (loc, EQ_EXPR, type,
11022 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11023 build_int_cst (TREE_TYPE (tem), 1)),
11024 build_int_cst (TREE_TYPE (tem), 0));
11026 /* Fold !X & 1 as X == 0. */
11027 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11028 && integer_onep (arg1))
11030 tem = TREE_OPERAND (arg0, 0);
11031 return fold_build2_loc (loc, EQ_EXPR, type, tem,
11032 build_int_cst (TREE_TYPE (tem), 0));
11035 /* Fold (X ^ Y) & Y as ~X & Y. */
11036 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11037 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11039 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11040 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11041 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11042 fold_convert_loc (loc, type, arg1));
11044 /* Fold (X ^ Y) & X as ~Y & X. */
11045 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11046 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11047 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11049 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11050 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11051 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11052 fold_convert_loc (loc, type, arg1));
11054 /* Fold X & (X ^ Y) as X & ~Y. */
11055 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11056 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11058 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11059 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11060 fold_convert_loc (loc, type, arg0),
11061 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11063 /* Fold X & (Y ^ X) as ~Y & X. */
11064 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11065 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11066 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11068 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11069 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11070 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11071 fold_convert_loc (loc, type, arg0));
11074 /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
11075 ((A & N) + B) & M -> (A + B) & M
11076 Similarly if (N & M) == 0,
11077 ((A | N) + B) & M -> (A + B) & M
11078 and for - instead of + (or unary - instead of +)
11079 and/or ^ instead of |.
11080 If B is constant and (B & M) == 0, fold into A & M. */
11081 if (host_integerp (arg1, 1))
11083 unsigned HOST_WIDE_INT cst1 = tree_low_cst (arg1, 1);
11084 if (~cst1 && (cst1 & (cst1 + 1)) == 0
11085 && INTEGRAL_TYPE_P (TREE_TYPE (arg0))
11086 && (TREE_CODE (arg0) == PLUS_EXPR
11087 || TREE_CODE (arg0) == MINUS_EXPR
11088 || TREE_CODE (arg0) == NEGATE_EXPR)
11089 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
11090 || TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE))
11094 unsigned HOST_WIDE_INT cst0;
11096 /* Now we know that arg0 is (C + D) or (C - D) or
11097 -C and arg1 (M) is == (1LL << cst) - 1.
11098 Store C into PMOP[0] and D into PMOP[1]. */
11099 pmop[0] = TREE_OPERAND (arg0, 0);
11101 if (TREE_CODE (arg0) != NEGATE_EXPR)
11103 pmop[1] = TREE_OPERAND (arg0, 1);
11107 if (!host_integerp (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11108 || (tree_low_cst (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11112 for (; which >= 0; which--)
11113 switch (TREE_CODE (pmop[which]))
11118 if (TREE_CODE (TREE_OPERAND (pmop[which], 1))
11121 /* tree_low_cst not used, because we don't care about
11123 cst0 = TREE_INT_CST_LOW (TREE_OPERAND (pmop[which], 1));
11125 if (TREE_CODE (pmop[which]) == BIT_AND_EXPR)
11130 else if (cst0 != 0)
11132 /* If C or D is of the form (A & N) where
11133 (N & M) == M, or of the form (A | N) or
11134 (A ^ N) where (N & M) == 0, replace it with A. */
11135 pmop[which] = TREE_OPERAND (pmop[which], 0);
11138 /* If C or D is a N where (N & M) == 0, it can be
11139 omitted (assumed 0). */
11140 if ((TREE_CODE (arg0) == PLUS_EXPR
11141 || (TREE_CODE (arg0) == MINUS_EXPR && which == 0))
11142 && (TREE_INT_CST_LOW (pmop[which]) & cst1) == 0)
11143 pmop[which] = NULL;
11149 /* Only build anything new if we optimized one or both arguments
11151 if (pmop[0] != TREE_OPERAND (arg0, 0)
11152 || (TREE_CODE (arg0) != NEGATE_EXPR
11153 && pmop[1] != TREE_OPERAND (arg0, 1)))
11155 tree utype = TREE_TYPE (arg0);
11156 if (! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
11158 /* Perform the operations in a type that has defined
11159 overflow behavior. */
11160 utype = unsigned_type_for (TREE_TYPE (arg0));
11161 if (pmop[0] != NULL)
11162 pmop[0] = fold_convert_loc (loc, utype, pmop[0]);
11163 if (pmop[1] != NULL)
11164 pmop[1] = fold_convert_loc (loc, utype, pmop[1]);
11167 if (TREE_CODE (arg0) == NEGATE_EXPR)
11168 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[0]);
11169 else if (TREE_CODE (arg0) == PLUS_EXPR)
11171 if (pmop[0] != NULL && pmop[1] != NULL)
11172 tem = fold_build2_loc (loc, PLUS_EXPR, utype,
11174 else if (pmop[0] != NULL)
11176 else if (pmop[1] != NULL)
11179 return build_int_cst (type, 0);
11181 else if (pmop[0] == NULL)
11182 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[1]);
11184 tem = fold_build2_loc (loc, MINUS_EXPR, utype,
11186 /* TEM is now the new binary +, - or unary - replacement. */
11187 tem = fold_build2_loc (loc, BIT_AND_EXPR, utype, tem,
11188 fold_convert_loc (loc, utype, arg1));
11189 return fold_convert_loc (loc, type, tem);
11194 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11195 if (t1 != NULL_TREE)
11197 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11198 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11199 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11202 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11204 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11205 && (~TREE_INT_CST_LOW (arg1)
11206 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11208 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11211 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11213 This results in more efficient code for machines without a NOR
11214 instruction. Combine will canonicalize to the first form
11215 which will allow use of NOR instructions provided by the
11216 backend if they exist. */
11217 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11218 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11220 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11221 build2 (BIT_IOR_EXPR, type,
11222 fold_convert_loc (loc, type,
11223 TREE_OPERAND (arg0, 0)),
11224 fold_convert_loc (loc, type,
11225 TREE_OPERAND (arg1, 0))));
11228 /* If arg0 is derived from the address of an object or function, we may
11229 be able to fold this expression using the object or function's
11231 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11233 unsigned HOST_WIDE_INT modulus, residue;
11234 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11236 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11237 integer_onep (arg1));
11239 /* This works because modulus is a power of 2. If this weren't the
11240 case, we'd have to replace it by its greatest power-of-2
11241 divisor: modulus & -modulus. */
11243 return build_int_cst (type, residue & low);
11246 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11247 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11248 if the new mask might be further optimized. */
11249 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11250 || TREE_CODE (arg0) == RSHIFT_EXPR)
11251 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11252 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11253 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11254 < TYPE_PRECISION (TREE_TYPE (arg0))
11255 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11256 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11258 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11259 unsigned HOST_WIDE_INT mask
11260 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11261 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11262 tree shift_type = TREE_TYPE (arg0);
11264 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11265 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11266 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11267 && TYPE_PRECISION (TREE_TYPE (arg0))
11268 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11270 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11271 tree arg00 = TREE_OPERAND (arg0, 0);
11272 /* See if more bits can be proven as zero because of
11274 if (TREE_CODE (arg00) == NOP_EXPR
11275 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11277 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11278 if (TYPE_PRECISION (inner_type)
11279 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11280 && TYPE_PRECISION (inner_type) < prec)
11282 prec = TYPE_PRECISION (inner_type);
11283 /* See if we can shorten the right shift. */
11285 shift_type = inner_type;
11288 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11289 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11290 zerobits <<= prec - shiftc;
11291 /* For arithmetic shift if sign bit could be set, zerobits
11292 can contain actually sign bits, so no transformation is
11293 possible, unless MASK masks them all away. In that
11294 case the shift needs to be converted into logical shift. */
11295 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11296 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11298 if ((mask & zerobits) == 0)
11299 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11305 /* ((X << 16) & 0xff00) is (X, 0). */
11306 if ((mask & zerobits) == mask)
11307 return omit_one_operand_loc (loc, type,
11308 build_int_cst (type, 0), arg0);
11310 newmask = mask | zerobits;
11311 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11315 /* Only do the transformation if NEWMASK is some integer
11317 for (prec = BITS_PER_UNIT;
11318 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11319 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11321 if (prec < HOST_BITS_PER_WIDE_INT
11322 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11326 if (shift_type != TREE_TYPE (arg0))
11328 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11329 fold_convert_loc (loc, shift_type,
11330 TREE_OPERAND (arg0, 0)),
11331 TREE_OPERAND (arg0, 1));
11332 tem = fold_convert_loc (loc, type, tem);
11336 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11337 if (!tree_int_cst_equal (newmaskt, arg1))
11338 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11346 /* Don't touch a floating-point divide by zero unless the mode
11347 of the constant can represent infinity. */
11348 if (TREE_CODE (arg1) == REAL_CST
11349 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11350 && real_zerop (arg1))
11353 /* Optimize A / A to 1.0 if we don't care about
11354 NaNs or Infinities. Skip the transformation
11355 for non-real operands. */
11356 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11357 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11358 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11359 && operand_equal_p (arg0, arg1, 0))
11361 tree r = build_real (TREE_TYPE (arg0), dconst1);
11363 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11366 /* The complex version of the above A / A optimization. */
11367 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11368 && operand_equal_p (arg0, arg1, 0))
11370 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11371 if (! HONOR_NANS (TYPE_MODE (elem_type))
11372 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11374 tree r = build_real (elem_type, dconst1);
11375 /* omit_two_operands will call fold_convert for us. */
11376 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11380 /* (-A) / (-B) -> A / B */
11381 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11382 return fold_build2_loc (loc, RDIV_EXPR, type,
11383 TREE_OPERAND (arg0, 0),
11384 negate_expr (arg1));
11385 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11386 return fold_build2_loc (loc, RDIV_EXPR, type,
11387 negate_expr (arg0),
11388 TREE_OPERAND (arg1, 0));
11390 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11391 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11392 && real_onep (arg1))
11393 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11395 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11396 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11397 && real_minus_onep (arg1))
11398 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11399 negate_expr (arg0)));
11401 /* If ARG1 is a constant, we can convert this to a multiply by the
11402 reciprocal. This does not have the same rounding properties,
11403 so only do this if -freciprocal-math. We can actually
11404 always safely do it if ARG1 is a power of two, but it's hard to
11405 tell if it is or not in a portable manner. */
11406 if (TREE_CODE (arg1) == REAL_CST)
11408 if (flag_reciprocal_math
11409 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11411 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11412 /* Find the reciprocal if optimizing and the result is exact. */
11416 r = TREE_REAL_CST (arg1);
11417 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11419 tem = build_real (type, r);
11420 return fold_build2_loc (loc, MULT_EXPR, type,
11421 fold_convert_loc (loc, type, arg0), tem);
11425 /* Convert A/B/C to A/(B*C). */
11426 if (flag_reciprocal_math
11427 && TREE_CODE (arg0) == RDIV_EXPR)
11428 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11429 fold_build2_loc (loc, MULT_EXPR, type,
11430 TREE_OPERAND (arg0, 1), arg1));
11432 /* Convert A/(B/C) to (A/B)*C. */
11433 if (flag_reciprocal_math
11434 && TREE_CODE (arg1) == RDIV_EXPR)
11435 return fold_build2_loc (loc, MULT_EXPR, type,
11436 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11437 TREE_OPERAND (arg1, 0)),
11438 TREE_OPERAND (arg1, 1));
11440 /* Convert C1/(X*C2) into (C1/C2)/X. */
11441 if (flag_reciprocal_math
11442 && TREE_CODE (arg1) == MULT_EXPR
11443 && TREE_CODE (arg0) == REAL_CST
11444 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11446 tree tem = const_binop (RDIV_EXPR, arg0,
11447 TREE_OPERAND (arg1, 1));
11449 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11450 TREE_OPERAND (arg1, 0));
11453 if (flag_unsafe_math_optimizations)
11455 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11456 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11458 /* Optimize sin(x)/cos(x) as tan(x). */
11459 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11460 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11461 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11462 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11463 CALL_EXPR_ARG (arg1, 0), 0))
11465 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11467 if (tanfn != NULL_TREE)
11468 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11471 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11472 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11473 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11474 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11475 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11476 CALL_EXPR_ARG (arg1, 0), 0))
11478 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11480 if (tanfn != NULL_TREE)
11482 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11483 CALL_EXPR_ARG (arg0, 0));
11484 return fold_build2_loc (loc, RDIV_EXPR, type,
11485 build_real (type, dconst1), tmp);
11489 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11490 NaNs or Infinities. */
11491 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11492 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11493 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11495 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11496 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11498 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11499 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11500 && operand_equal_p (arg00, arg01, 0))
11502 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11504 if (cosfn != NULL_TREE)
11505 return build_call_expr_loc (loc, cosfn, 1, arg00);
11509 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11510 NaNs or Infinities. */
11511 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11512 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11513 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11515 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11516 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11518 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11519 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11520 && operand_equal_p (arg00, arg01, 0))
11522 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11524 if (cosfn != NULL_TREE)
11526 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11527 return fold_build2_loc (loc, RDIV_EXPR, type,
11528 build_real (type, dconst1),
11534 /* Optimize pow(x,c)/x as pow(x,c-1). */
11535 if (fcode0 == BUILT_IN_POW
11536 || fcode0 == BUILT_IN_POWF
11537 || fcode0 == BUILT_IN_POWL)
11539 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11540 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11541 if (TREE_CODE (arg01) == REAL_CST
11542 && !TREE_OVERFLOW (arg01)
11543 && operand_equal_p (arg1, arg00, 0))
11545 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11549 c = TREE_REAL_CST (arg01);
11550 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11551 arg = build_real (type, c);
11552 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11556 /* Optimize a/root(b/c) into a*root(c/b). */
11557 if (BUILTIN_ROOT_P (fcode1))
11559 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11561 if (TREE_CODE (rootarg) == RDIV_EXPR)
11563 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11564 tree b = TREE_OPERAND (rootarg, 0);
11565 tree c = TREE_OPERAND (rootarg, 1);
11567 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
11569 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
11570 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
11574 /* Optimize x/expN(y) into x*expN(-y). */
11575 if (BUILTIN_EXPONENT_P (fcode1))
11577 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11578 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11579 arg1 = build_call_expr_loc (loc,
11581 fold_convert_loc (loc, type, arg));
11582 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11585 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11586 if (fcode1 == BUILT_IN_POW
11587 || fcode1 == BUILT_IN_POWF
11588 || fcode1 == BUILT_IN_POWL)
11590 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11591 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11592 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11593 tree neg11 = fold_convert_loc (loc, type,
11594 negate_expr (arg11));
11595 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
11596 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11601 case TRUNC_DIV_EXPR:
11602 /* Optimize (X & (-A)) / A where A is a power of 2,
11604 if (TREE_CODE (arg0) == BIT_AND_EXPR
11605 && !TYPE_UNSIGNED (type) && TREE_CODE (arg1) == INTEGER_CST
11606 && integer_pow2p (arg1) && tree_int_cst_sgn (arg1) > 0)
11608 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (arg1),
11609 arg1, TREE_OPERAND (arg0, 1));
11610 if (sum && integer_zerop (sum)) {
11611 unsigned long pow2;
11613 if (TREE_INT_CST_LOW (arg1))
11614 pow2 = exact_log2 (TREE_INT_CST_LOW (arg1));
11616 pow2 = exact_log2 (TREE_INT_CST_HIGH (arg1))
11617 + HOST_BITS_PER_WIDE_INT;
11619 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11620 TREE_OPERAND (arg0, 0),
11621 build_int_cst (integer_type_node, pow2));
11627 case FLOOR_DIV_EXPR:
11628 /* Simplify A / (B << N) where A and B are positive and B is
11629 a power of 2, to A >> (N + log2(B)). */
11630 strict_overflow_p = false;
11631 if (TREE_CODE (arg1) == LSHIFT_EXPR
11632 && (TYPE_UNSIGNED (type)
11633 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11635 tree sval = TREE_OPERAND (arg1, 0);
11636 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11638 tree sh_cnt = TREE_OPERAND (arg1, 1);
11639 unsigned long pow2;
11641 if (TREE_INT_CST_LOW (sval))
11642 pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11644 pow2 = exact_log2 (TREE_INT_CST_HIGH (sval))
11645 + HOST_BITS_PER_WIDE_INT;
11647 if (strict_overflow_p)
11648 fold_overflow_warning (("assuming signed overflow does not "
11649 "occur when simplifying A / (B << N)"),
11650 WARN_STRICT_OVERFLOW_MISC);
11652 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
11654 build_int_cst (TREE_TYPE (sh_cnt),
11656 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11657 fold_convert_loc (loc, type, arg0), sh_cnt);
11661 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11662 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11663 if (INTEGRAL_TYPE_P (type)
11664 && TYPE_UNSIGNED (type)
11665 && code == FLOOR_DIV_EXPR)
11666 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
11670 case ROUND_DIV_EXPR:
11671 case CEIL_DIV_EXPR:
11672 case EXACT_DIV_EXPR:
11673 if (integer_onep (arg1))
11674 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11675 if (integer_zerop (arg1))
11677 /* X / -1 is -X. */
11678 if (!TYPE_UNSIGNED (type)
11679 && TREE_CODE (arg1) == INTEGER_CST
11680 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11681 && TREE_INT_CST_HIGH (arg1) == -1)
11682 return fold_convert_loc (loc, type, negate_expr (arg0));
11684 /* Convert -A / -B to A / B when the type is signed and overflow is
11686 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11687 && TREE_CODE (arg0) == NEGATE_EXPR
11688 && negate_expr_p (arg1))
11690 if (INTEGRAL_TYPE_P (type))
11691 fold_overflow_warning (("assuming signed overflow does not occur "
11692 "when distributing negation across "
11694 WARN_STRICT_OVERFLOW_MISC);
11695 return fold_build2_loc (loc, code, type,
11696 fold_convert_loc (loc, type,
11697 TREE_OPERAND (arg0, 0)),
11698 fold_convert_loc (loc, type,
11699 negate_expr (arg1)));
11701 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11702 && TREE_CODE (arg1) == NEGATE_EXPR
11703 && negate_expr_p (arg0))
11705 if (INTEGRAL_TYPE_P (type))
11706 fold_overflow_warning (("assuming signed overflow does not occur "
11707 "when distributing negation across "
11709 WARN_STRICT_OVERFLOW_MISC);
11710 return fold_build2_loc (loc, code, type,
11711 fold_convert_loc (loc, type,
11712 negate_expr (arg0)),
11713 fold_convert_loc (loc, type,
11714 TREE_OPERAND (arg1, 0)));
11717 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11718 operation, EXACT_DIV_EXPR.
11720 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11721 At one time others generated faster code, it's not clear if they do
11722 after the last round to changes to the DIV code in expmed.c. */
11723 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11724 && multiple_of_p (type, arg0, arg1))
11725 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
11727 strict_overflow_p = false;
11728 if (TREE_CODE (arg1) == INTEGER_CST
11729 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11730 &strict_overflow_p)))
11732 if (strict_overflow_p)
11733 fold_overflow_warning (("assuming signed overflow does not occur "
11734 "when simplifying division"),
11735 WARN_STRICT_OVERFLOW_MISC);
11736 return fold_convert_loc (loc, type, tem);
11741 case CEIL_MOD_EXPR:
11742 case FLOOR_MOD_EXPR:
11743 case ROUND_MOD_EXPR:
11744 case TRUNC_MOD_EXPR:
11745 /* X % 1 is always zero, but be sure to preserve any side
11747 if (integer_onep (arg1))
11748 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11750 /* X % 0, return X % 0 unchanged so that we can get the
11751 proper warnings and errors. */
11752 if (integer_zerop (arg1))
11755 /* 0 % X is always zero, but be sure to preserve any side
11756 effects in X. Place this after checking for X == 0. */
11757 if (integer_zerop (arg0))
11758 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11760 /* X % -1 is zero. */
11761 if (!TYPE_UNSIGNED (type)
11762 && TREE_CODE (arg1) == INTEGER_CST
11763 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11764 && TREE_INT_CST_HIGH (arg1) == -1)
11765 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11767 /* X % -C is the same as X % C. */
11768 if (code == TRUNC_MOD_EXPR
11769 && !TYPE_UNSIGNED (type)
11770 && TREE_CODE (arg1) == INTEGER_CST
11771 && !TREE_OVERFLOW (arg1)
11772 && TREE_INT_CST_HIGH (arg1) < 0
11773 && !TYPE_OVERFLOW_TRAPS (type)
11774 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11775 && !sign_bit_p (arg1, arg1))
11776 return fold_build2_loc (loc, code, type,
11777 fold_convert_loc (loc, type, arg0),
11778 fold_convert_loc (loc, type,
11779 negate_expr (arg1)));
11781 /* X % -Y is the same as X % Y. */
11782 if (code == TRUNC_MOD_EXPR
11783 && !TYPE_UNSIGNED (type)
11784 && TREE_CODE (arg1) == NEGATE_EXPR
11785 && !TYPE_OVERFLOW_TRAPS (type))
11786 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
11787 fold_convert_loc (loc, type,
11788 TREE_OPERAND (arg1, 0)));
11790 strict_overflow_p = false;
11791 if (TREE_CODE (arg1) == INTEGER_CST
11792 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11793 &strict_overflow_p)))
11795 if (strict_overflow_p)
11796 fold_overflow_warning (("assuming signed overflow does not occur "
11797 "when simplifying modulus"),
11798 WARN_STRICT_OVERFLOW_MISC);
11799 return fold_convert_loc (loc, type, tem);
11802 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11803 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11804 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11805 && (TYPE_UNSIGNED (type)
11806 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11809 /* Also optimize A % (C << N) where C is a power of 2,
11810 to A & ((C << N) - 1). */
11811 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11812 c = TREE_OPERAND (arg1, 0);
11814 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11817 = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
11818 build_int_cst (TREE_TYPE (arg1), 1));
11819 if (strict_overflow_p)
11820 fold_overflow_warning (("assuming signed overflow does not "
11821 "occur when simplifying "
11822 "X % (power of two)"),
11823 WARN_STRICT_OVERFLOW_MISC);
11824 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11825 fold_convert_loc (loc, type, arg0),
11826 fold_convert_loc (loc, type, mask));
11834 if (integer_all_onesp (arg0))
11835 return omit_one_operand_loc (loc, type, arg0, arg1);
11839 /* Optimize -1 >> x for arithmetic right shifts. */
11840 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11841 && tree_expr_nonnegative_p (arg1))
11842 return omit_one_operand_loc (loc, type, arg0, arg1);
11843 /* ... fall through ... */
11847 if (integer_zerop (arg1))
11848 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11849 if (integer_zerop (arg0))
11850 return omit_one_operand_loc (loc, type, arg0, arg1);
11852 /* Since negative shift count is not well-defined,
11853 don't try to compute it in the compiler. */
11854 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11857 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11858 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11859 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11860 && host_integerp (TREE_OPERAND (arg0, 1), false)
11861 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11863 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11864 + TREE_INT_CST_LOW (arg1));
11866 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11867 being well defined. */
11868 if (low >= TYPE_PRECISION (type))
11870 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11871 low = low % TYPE_PRECISION (type);
11872 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11873 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
11874 TREE_OPERAND (arg0, 0));
11876 low = TYPE_PRECISION (type) - 1;
11879 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
11880 build_int_cst (type, low));
11883 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11884 into x & ((unsigned)-1 >> c) for unsigned types. */
11885 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11886 || (TYPE_UNSIGNED (type)
11887 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11888 && host_integerp (arg1, false)
11889 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11890 && host_integerp (TREE_OPERAND (arg0, 1), false)
11891 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11893 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11894 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11900 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11902 lshift = build_int_cst (type, -1);
11903 lshift = int_const_binop (code, lshift, arg1);
11905 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
11909 /* Rewrite an LROTATE_EXPR by a constant into an
11910 RROTATE_EXPR by a new constant. */
11911 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11913 tree tem = build_int_cst (TREE_TYPE (arg1),
11914 TYPE_PRECISION (type));
11915 tem = const_binop (MINUS_EXPR, tem, arg1);
11916 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
11919 /* If we have a rotate of a bit operation with the rotate count and
11920 the second operand of the bit operation both constant,
11921 permute the two operations. */
11922 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11923 && (TREE_CODE (arg0) == BIT_AND_EXPR
11924 || TREE_CODE (arg0) == BIT_IOR_EXPR
11925 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11926 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11927 return fold_build2_loc (loc, TREE_CODE (arg0), type,
11928 fold_build2_loc (loc, code, type,
11929 TREE_OPERAND (arg0, 0), arg1),
11930 fold_build2_loc (loc, code, type,
11931 TREE_OPERAND (arg0, 1), arg1));
11933 /* Two consecutive rotates adding up to the precision of the
11934 type can be ignored. */
11935 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11936 && TREE_CODE (arg0) == RROTATE_EXPR
11937 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11938 && TREE_INT_CST_HIGH (arg1) == 0
11939 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11940 && ((TREE_INT_CST_LOW (arg1)
11941 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11942 == (unsigned int) TYPE_PRECISION (type)))
11943 return TREE_OPERAND (arg0, 0);
11945 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11946 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11947 if the latter can be further optimized. */
11948 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11949 && TREE_CODE (arg0) == BIT_AND_EXPR
11950 && TREE_CODE (arg1) == INTEGER_CST
11951 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11953 tree mask = fold_build2_loc (loc, code, type,
11954 fold_convert_loc (loc, type,
11955 TREE_OPERAND (arg0, 1)),
11957 tree shift = fold_build2_loc (loc, code, type,
11958 fold_convert_loc (loc, type,
11959 TREE_OPERAND (arg0, 0)),
11961 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
11969 if (operand_equal_p (arg0, arg1, 0))
11970 return omit_one_operand_loc (loc, type, arg0, arg1);
11971 if (INTEGRAL_TYPE_P (type)
11972 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11973 return omit_one_operand_loc (loc, type, arg1, arg0);
11974 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
11980 if (operand_equal_p (arg0, arg1, 0))
11981 return omit_one_operand_loc (loc, type, arg0, arg1);
11982 if (INTEGRAL_TYPE_P (type)
11983 && TYPE_MAX_VALUE (type)
11984 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11985 return omit_one_operand_loc (loc, type, arg1, arg0);
11986 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
11991 case TRUTH_ANDIF_EXPR:
11992 /* Note that the operands of this must be ints
11993 and their values must be 0 or 1.
11994 ("true" is a fixed value perhaps depending on the language.) */
11995 /* If first arg is constant zero, return it. */
11996 if (integer_zerop (arg0))
11997 return fold_convert_loc (loc, type, arg0);
11998 case TRUTH_AND_EXPR:
11999 /* If either arg is constant true, drop it. */
12000 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12001 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12002 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
12003 /* Preserve sequence points. */
12004 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12005 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12006 /* If second arg is constant zero, result is zero, but first arg
12007 must be evaluated. */
12008 if (integer_zerop (arg1))
12009 return omit_one_operand_loc (loc, type, arg1, arg0);
12010 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
12011 case will be handled here. */
12012 if (integer_zerop (arg0))
12013 return omit_one_operand_loc (loc, type, arg0, arg1);
12015 /* !X && X is always false. */
12016 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12017 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12018 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12019 /* X && !X is always false. */
12020 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12021 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12022 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12024 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12025 means A >= Y && A != MAX, but in this case we know that
12028 if (!TREE_SIDE_EFFECTS (arg0)
12029 && !TREE_SIDE_EFFECTS (arg1))
12031 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
12032 if (tem && !operand_equal_p (tem, arg0, 0))
12033 return fold_build2_loc (loc, code, type, tem, arg1);
12035 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12036 if (tem && !operand_equal_p (tem, arg1, 0))
12037 return fold_build2_loc (loc, code, type, arg0, tem);
12040 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12046 case TRUTH_ORIF_EXPR:
12047 /* Note that the operands of this must be ints
12048 and their values must be 0 or true.
12049 ("true" is a fixed value perhaps depending on the language.) */
12050 /* If first arg is constant true, return it. */
12051 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12052 return fold_convert_loc (loc, type, arg0);
12053 case TRUTH_OR_EXPR:
12054 /* If either arg is constant zero, drop it. */
12055 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12056 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12057 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12058 /* Preserve sequence points. */
12059 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12060 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12061 /* If second arg is constant true, result is true, but we must
12062 evaluate first arg. */
12063 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12064 return omit_one_operand_loc (loc, type, arg1, arg0);
12065 /* Likewise for first arg, but note this only occurs here for
12067 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12068 return omit_one_operand_loc (loc, type, arg0, arg1);
12070 /* !X || X is always true. */
12071 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12072 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12073 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12074 /* X || !X is always true. */
12075 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12076 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12077 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12079 /* (X && !Y) || (!X && Y) is X ^ Y */
12080 if (TREE_CODE (arg0) == TRUTH_AND_EXPR
12081 && TREE_CODE (arg1) == TRUTH_AND_EXPR)
12083 tree a0, a1, l0, l1, n0, n1;
12085 a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
12086 a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
12088 l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12089 l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
12091 n0 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l0);
12092 n1 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l1);
12094 if ((operand_equal_p (n0, a0, 0)
12095 && operand_equal_p (n1, a1, 0))
12096 || (operand_equal_p (n0, a1, 0)
12097 && operand_equal_p (n1, a0, 0)))
12098 return fold_build2_loc (loc, TRUTH_XOR_EXPR, type, l0, n1);
12101 if ((tem = fold_truth_andor (loc, code, type, arg0, arg1, op0, op1))
12107 case TRUTH_XOR_EXPR:
12108 /* If the second arg is constant zero, drop it. */
12109 if (integer_zerop (arg1))
12110 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12111 /* If the second arg is constant true, this is a logical inversion. */
12112 if (integer_onep (arg1))
12114 /* Only call invert_truthvalue if operand is a truth value. */
12115 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12116 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12118 tem = invert_truthvalue_loc (loc, arg0);
12119 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12121 /* Identical arguments cancel to zero. */
12122 if (operand_equal_p (arg0, arg1, 0))
12123 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12125 /* !X ^ X is always true. */
12126 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12127 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12128 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12130 /* X ^ !X is always true. */
12131 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12132 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12133 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12142 tem = fold_comparison (loc, code, type, op0, op1);
12143 if (tem != NULL_TREE)
12146 /* bool_var != 0 becomes bool_var. */
12147 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12148 && code == NE_EXPR)
12149 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12151 /* bool_var == 1 becomes bool_var. */
12152 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12153 && code == EQ_EXPR)
12154 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12156 /* bool_var != 1 becomes !bool_var. */
12157 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12158 && code == NE_EXPR)
12159 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12160 fold_convert_loc (loc, type, arg0));
12162 /* bool_var == 0 becomes !bool_var. */
12163 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12164 && code == EQ_EXPR)
12165 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12166 fold_convert_loc (loc, type, arg0));
12168 /* !exp != 0 becomes !exp */
12169 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12170 && code == NE_EXPR)
12171 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12173 /* If this is an equality comparison of the address of two non-weak,
12174 unaliased symbols neither of which are extern (since we do not
12175 have access to attributes for externs), then we know the result. */
12176 if (TREE_CODE (arg0) == ADDR_EXPR
12177 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12178 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12179 && ! lookup_attribute ("alias",
12180 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12181 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12182 && TREE_CODE (arg1) == ADDR_EXPR
12183 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12184 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12185 && ! lookup_attribute ("alias",
12186 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12187 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12189 /* We know that we're looking at the address of two
12190 non-weak, unaliased, static _DECL nodes.
12192 It is both wasteful and incorrect to call operand_equal_p
12193 to compare the two ADDR_EXPR nodes. It is wasteful in that
12194 all we need to do is test pointer equality for the arguments
12195 to the two ADDR_EXPR nodes. It is incorrect to use
12196 operand_equal_p as that function is NOT equivalent to a
12197 C equality test. It can in fact return false for two
12198 objects which would test as equal using the C equality
12200 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12201 return constant_boolean_node (equal
12202 ? code == EQ_EXPR : code != EQ_EXPR,
12206 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12207 a MINUS_EXPR of a constant, we can convert it into a comparison with
12208 a revised constant as long as no overflow occurs. */
12209 if (TREE_CODE (arg1) == INTEGER_CST
12210 && (TREE_CODE (arg0) == PLUS_EXPR
12211 || TREE_CODE (arg0) == MINUS_EXPR)
12212 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12213 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12214 ? MINUS_EXPR : PLUS_EXPR,
12215 fold_convert_loc (loc, TREE_TYPE (arg0),
12217 TREE_OPERAND (arg0, 1)))
12218 && !TREE_OVERFLOW (tem))
12219 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12221 /* Similarly for a NEGATE_EXPR. */
12222 if (TREE_CODE (arg0) == NEGATE_EXPR
12223 && TREE_CODE (arg1) == INTEGER_CST
12224 && 0 != (tem = negate_expr (fold_convert_loc (loc, TREE_TYPE (arg0),
12226 && TREE_CODE (tem) == INTEGER_CST
12227 && !TREE_OVERFLOW (tem))
12228 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12230 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12231 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12232 && TREE_CODE (arg1) == INTEGER_CST
12233 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12234 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12235 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12236 fold_convert_loc (loc,
12239 TREE_OPERAND (arg0, 1)));
12241 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12242 if ((TREE_CODE (arg0) == PLUS_EXPR
12243 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12244 || TREE_CODE (arg0) == MINUS_EXPR)
12245 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12248 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12249 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12251 tree val = TREE_OPERAND (arg0, 1);
12252 return omit_two_operands_loc (loc, type,
12253 fold_build2_loc (loc, code, type,
12255 build_int_cst (TREE_TYPE (val),
12257 TREE_OPERAND (arg0, 0), arg1);
12260 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12261 if (TREE_CODE (arg0) == MINUS_EXPR
12262 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12263 && operand_equal_p (tree_strip_nop_conversions (TREE_OPERAND (arg0,
12266 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12268 return omit_two_operands_loc (loc, type,
12270 ? boolean_true_node : boolean_false_node,
12271 TREE_OPERAND (arg0, 1), arg1);
12274 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12275 for !=. Don't do this for ordered comparisons due to overflow. */
12276 if (TREE_CODE (arg0) == MINUS_EXPR
12277 && integer_zerop (arg1))
12278 return fold_build2_loc (loc, code, type,
12279 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12281 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12282 if (TREE_CODE (arg0) == ABS_EXPR
12283 && (integer_zerop (arg1) || real_zerop (arg1)))
12284 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12286 /* If this is an EQ or NE comparison with zero and ARG0 is
12287 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12288 two operations, but the latter can be done in one less insn
12289 on machines that have only two-operand insns or on which a
12290 constant cannot be the first operand. */
12291 if (TREE_CODE (arg0) == BIT_AND_EXPR
12292 && integer_zerop (arg1))
12294 tree arg00 = TREE_OPERAND (arg0, 0);
12295 tree arg01 = TREE_OPERAND (arg0, 1);
12296 if (TREE_CODE (arg00) == LSHIFT_EXPR
12297 && integer_onep (TREE_OPERAND (arg00, 0)))
12299 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12300 arg01, TREE_OPERAND (arg00, 1));
12301 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12302 build_int_cst (TREE_TYPE (arg0), 1));
12303 return fold_build2_loc (loc, code, type,
12304 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12307 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12308 && integer_onep (TREE_OPERAND (arg01, 0)))
12310 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12311 arg00, TREE_OPERAND (arg01, 1));
12312 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12313 build_int_cst (TREE_TYPE (arg0), 1));
12314 return fold_build2_loc (loc, code, type,
12315 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12320 /* If this is an NE or EQ comparison of zero against the result of a
12321 signed MOD operation whose second operand is a power of 2, make
12322 the MOD operation unsigned since it is simpler and equivalent. */
12323 if (integer_zerop (arg1)
12324 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12325 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12326 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12327 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12328 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12329 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12331 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12332 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12333 fold_convert_loc (loc, newtype,
12334 TREE_OPERAND (arg0, 0)),
12335 fold_convert_loc (loc, newtype,
12336 TREE_OPERAND (arg0, 1)));
12338 return fold_build2_loc (loc, code, type, newmod,
12339 fold_convert_loc (loc, newtype, arg1));
12342 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12343 C1 is a valid shift constant, and C2 is a power of two, i.e.
12345 if (TREE_CODE (arg0) == BIT_AND_EXPR
12346 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12347 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12349 && integer_pow2p (TREE_OPERAND (arg0, 1))
12350 && integer_zerop (arg1))
12352 tree itype = TREE_TYPE (arg0);
12353 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12354 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12356 /* Check for a valid shift count. */
12357 if (TREE_INT_CST_HIGH (arg001) == 0
12358 && TREE_INT_CST_LOW (arg001) < prec)
12360 tree arg01 = TREE_OPERAND (arg0, 1);
12361 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12362 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12363 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12364 can be rewritten as (X & (C2 << C1)) != 0. */
12365 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12367 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12368 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12369 return fold_build2_loc (loc, code, type, tem,
12370 fold_convert_loc (loc, itype, arg1));
12372 /* Otherwise, for signed (arithmetic) shifts,
12373 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12374 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12375 else if (!TYPE_UNSIGNED (itype))
12376 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12377 arg000, build_int_cst (itype, 0));
12378 /* Otherwise, of unsigned (logical) shifts,
12379 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12380 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12382 return omit_one_operand_loc (loc, type,
12383 code == EQ_EXPR ? integer_one_node
12384 : integer_zero_node,
12389 /* If we have (A & C) == C where C is a power of 2, convert this into
12390 (A & C) != 0. Similarly for NE_EXPR. */
12391 if (TREE_CODE (arg0) == BIT_AND_EXPR
12392 && integer_pow2p (TREE_OPERAND (arg0, 1))
12393 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12394 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12395 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12396 integer_zero_node));
12398 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12399 bit, then fold the expression into A < 0 or A >= 0. */
12400 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12404 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12405 Similarly for NE_EXPR. */
12406 if (TREE_CODE (arg0) == BIT_AND_EXPR
12407 && TREE_CODE (arg1) == INTEGER_CST
12408 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12410 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12411 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12412 TREE_OPERAND (arg0, 1));
12414 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12415 fold_convert_loc (loc, TREE_TYPE (arg0), arg1),
12417 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12418 if (integer_nonzerop (dandnotc))
12419 return omit_one_operand_loc (loc, type, rslt, arg0);
12422 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12423 Similarly for NE_EXPR. */
12424 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12425 && TREE_CODE (arg1) == INTEGER_CST
12426 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12428 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12430 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12431 TREE_OPERAND (arg0, 1),
12432 fold_convert_loc (loc, TREE_TYPE (arg0), notd));
12433 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12434 if (integer_nonzerop (candnotd))
12435 return omit_one_operand_loc (loc, type, rslt, arg0);
12438 /* If this is a comparison of a field, we may be able to simplify it. */
12439 if ((TREE_CODE (arg0) == COMPONENT_REF
12440 || TREE_CODE (arg0) == BIT_FIELD_REF)
12441 /* Handle the constant case even without -O
12442 to make sure the warnings are given. */
12443 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12445 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12450 /* Optimize comparisons of strlen vs zero to a compare of the
12451 first character of the string vs zero. To wit,
12452 strlen(ptr) == 0 => *ptr == 0
12453 strlen(ptr) != 0 => *ptr != 0
12454 Other cases should reduce to one of these two (or a constant)
12455 due to the return value of strlen being unsigned. */
12456 if (TREE_CODE (arg0) == CALL_EXPR
12457 && integer_zerop (arg1))
12459 tree fndecl = get_callee_fndecl (arg0);
12462 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12463 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12464 && call_expr_nargs (arg0) == 1
12465 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12467 tree iref = build_fold_indirect_ref_loc (loc,
12468 CALL_EXPR_ARG (arg0, 0));
12469 return fold_build2_loc (loc, code, type, iref,
12470 build_int_cst (TREE_TYPE (iref), 0));
12474 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12475 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12476 if (TREE_CODE (arg0) == RSHIFT_EXPR
12477 && integer_zerop (arg1)
12478 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12480 tree arg00 = TREE_OPERAND (arg0, 0);
12481 tree arg01 = TREE_OPERAND (arg0, 1);
12482 tree itype = TREE_TYPE (arg00);
12483 if (TREE_INT_CST_HIGH (arg01) == 0
12484 && TREE_INT_CST_LOW (arg01)
12485 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12487 if (TYPE_UNSIGNED (itype))
12489 itype = signed_type_for (itype);
12490 arg00 = fold_convert_loc (loc, itype, arg00);
12492 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12493 type, arg00, build_int_cst (itype, 0));
12497 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12498 if (integer_zerop (arg1)
12499 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12500 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12501 TREE_OPERAND (arg0, 1));
12503 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12504 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12505 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12506 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12507 build_int_cst (TREE_TYPE (arg0), 0));
12508 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12509 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12510 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12511 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12512 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12513 build_int_cst (TREE_TYPE (arg0), 0));
12515 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12516 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12517 && TREE_CODE (arg1) == INTEGER_CST
12518 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12519 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12520 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12521 TREE_OPERAND (arg0, 1), arg1));
12523 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12524 (X & C) == 0 when C is a single bit. */
12525 if (TREE_CODE (arg0) == BIT_AND_EXPR
12526 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12527 && integer_zerop (arg1)
12528 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12530 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12531 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12532 TREE_OPERAND (arg0, 1));
12533 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12535 fold_convert_loc (loc, TREE_TYPE (arg0),
12539 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12540 constant C is a power of two, i.e. a single bit. */
12541 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12542 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12543 && integer_zerop (arg1)
12544 && integer_pow2p (TREE_OPERAND (arg0, 1))
12545 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12546 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12548 tree arg00 = TREE_OPERAND (arg0, 0);
12549 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12550 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12553 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12554 when is C is a power of two, i.e. a single bit. */
12555 if (TREE_CODE (arg0) == BIT_AND_EXPR
12556 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12557 && integer_zerop (arg1)
12558 && integer_pow2p (TREE_OPERAND (arg0, 1))
12559 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12560 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12562 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12563 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
12564 arg000, TREE_OPERAND (arg0, 1));
12565 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12566 tem, build_int_cst (TREE_TYPE (tem), 0));
12569 if (integer_zerop (arg1)
12570 && tree_expr_nonzero_p (arg0))
12572 tree res = constant_boolean_node (code==NE_EXPR, type);
12573 return omit_one_operand_loc (loc, type, res, arg0);
12576 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12577 if (TREE_CODE (arg0) == NEGATE_EXPR
12578 && TREE_CODE (arg1) == NEGATE_EXPR)
12579 return fold_build2_loc (loc, code, type,
12580 TREE_OPERAND (arg0, 0),
12581 fold_convert_loc (loc, TREE_TYPE (arg0),
12582 TREE_OPERAND (arg1, 0)));
12584 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12585 if (TREE_CODE (arg0) == BIT_AND_EXPR
12586 && TREE_CODE (arg1) == BIT_AND_EXPR)
12588 tree arg00 = TREE_OPERAND (arg0, 0);
12589 tree arg01 = TREE_OPERAND (arg0, 1);
12590 tree arg10 = TREE_OPERAND (arg1, 0);
12591 tree arg11 = TREE_OPERAND (arg1, 1);
12592 tree itype = TREE_TYPE (arg0);
12594 if (operand_equal_p (arg01, arg11, 0))
12595 return fold_build2_loc (loc, code, type,
12596 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12597 fold_build2_loc (loc,
12598 BIT_XOR_EXPR, itype,
12601 build_int_cst (itype, 0));
12603 if (operand_equal_p (arg01, arg10, 0))
12604 return fold_build2_loc (loc, code, type,
12605 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12606 fold_build2_loc (loc,
12607 BIT_XOR_EXPR, itype,
12610 build_int_cst (itype, 0));
12612 if (operand_equal_p (arg00, arg11, 0))
12613 return fold_build2_loc (loc, code, type,
12614 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12615 fold_build2_loc (loc,
12616 BIT_XOR_EXPR, itype,
12619 build_int_cst (itype, 0));
12621 if (operand_equal_p (arg00, arg10, 0))
12622 return fold_build2_loc (loc, code, type,
12623 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12624 fold_build2_loc (loc,
12625 BIT_XOR_EXPR, itype,
12628 build_int_cst (itype, 0));
12631 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12632 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12634 tree arg00 = TREE_OPERAND (arg0, 0);
12635 tree arg01 = TREE_OPERAND (arg0, 1);
12636 tree arg10 = TREE_OPERAND (arg1, 0);
12637 tree arg11 = TREE_OPERAND (arg1, 1);
12638 tree itype = TREE_TYPE (arg0);
12640 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12641 operand_equal_p guarantees no side-effects so we don't need
12642 to use omit_one_operand on Z. */
12643 if (operand_equal_p (arg01, arg11, 0))
12644 return fold_build2_loc (loc, code, type, arg00,
12645 fold_convert_loc (loc, TREE_TYPE (arg00),
12647 if (operand_equal_p (arg01, arg10, 0))
12648 return fold_build2_loc (loc, code, type, arg00,
12649 fold_convert_loc (loc, TREE_TYPE (arg00),
12651 if (operand_equal_p (arg00, arg11, 0))
12652 return fold_build2_loc (loc, code, type, arg01,
12653 fold_convert_loc (loc, TREE_TYPE (arg01),
12655 if (operand_equal_p (arg00, arg10, 0))
12656 return fold_build2_loc (loc, code, type, arg01,
12657 fold_convert_loc (loc, TREE_TYPE (arg01),
12660 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12661 if (TREE_CODE (arg01) == INTEGER_CST
12662 && TREE_CODE (arg11) == INTEGER_CST)
12664 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg01,
12665 fold_convert_loc (loc, itype, arg11));
12666 tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00, tem);
12667 return fold_build2_loc (loc, code, type, tem,
12668 fold_convert_loc (loc, itype, arg10));
12672 /* Attempt to simplify equality/inequality comparisons of complex
12673 values. Only lower the comparison if the result is known or
12674 can be simplified to a single scalar comparison. */
12675 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12676 || TREE_CODE (arg0) == COMPLEX_CST)
12677 && (TREE_CODE (arg1) == COMPLEX_EXPR
12678 || TREE_CODE (arg1) == COMPLEX_CST))
12680 tree real0, imag0, real1, imag1;
12683 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12685 real0 = TREE_OPERAND (arg0, 0);
12686 imag0 = TREE_OPERAND (arg0, 1);
12690 real0 = TREE_REALPART (arg0);
12691 imag0 = TREE_IMAGPART (arg0);
12694 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12696 real1 = TREE_OPERAND (arg1, 0);
12697 imag1 = TREE_OPERAND (arg1, 1);
12701 real1 = TREE_REALPART (arg1);
12702 imag1 = TREE_IMAGPART (arg1);
12705 rcond = fold_binary_loc (loc, code, type, real0, real1);
12706 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12708 if (integer_zerop (rcond))
12710 if (code == EQ_EXPR)
12711 return omit_two_operands_loc (loc, type, boolean_false_node,
12713 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
12717 if (code == NE_EXPR)
12718 return omit_two_operands_loc (loc, type, boolean_true_node,
12720 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
12724 icond = fold_binary_loc (loc, code, type, imag0, imag1);
12725 if (icond && TREE_CODE (icond) == INTEGER_CST)
12727 if (integer_zerop (icond))
12729 if (code == EQ_EXPR)
12730 return omit_two_operands_loc (loc, type, boolean_false_node,
12732 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
12736 if (code == NE_EXPR)
12737 return omit_two_operands_loc (loc, type, boolean_true_node,
12739 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
12750 tem = fold_comparison (loc, code, type, op0, op1);
12751 if (tem != NULL_TREE)
12754 /* Transform comparisons of the form X +- C CMP X. */
12755 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12756 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12757 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12758 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12759 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12760 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12762 tree arg01 = TREE_OPERAND (arg0, 1);
12763 enum tree_code code0 = TREE_CODE (arg0);
12766 if (TREE_CODE (arg01) == REAL_CST)
12767 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12769 is_positive = tree_int_cst_sgn (arg01);
12771 /* (X - c) > X becomes false. */
12772 if (code == GT_EXPR
12773 && ((code0 == MINUS_EXPR && is_positive >= 0)
12774 || (code0 == PLUS_EXPR && is_positive <= 0)))
12776 if (TREE_CODE (arg01) == INTEGER_CST
12777 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12778 fold_overflow_warning (("assuming signed overflow does not "
12779 "occur when assuming that (X - c) > X "
12780 "is always false"),
12781 WARN_STRICT_OVERFLOW_ALL);
12782 return constant_boolean_node (0, type);
12785 /* Likewise (X + c) < X becomes false. */
12786 if (code == LT_EXPR
12787 && ((code0 == PLUS_EXPR && is_positive >= 0)
12788 || (code0 == MINUS_EXPR && is_positive <= 0)))
12790 if (TREE_CODE (arg01) == INTEGER_CST
12791 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12792 fold_overflow_warning (("assuming signed overflow does not "
12793 "occur when assuming that "
12794 "(X + c) < X is always false"),
12795 WARN_STRICT_OVERFLOW_ALL);
12796 return constant_boolean_node (0, type);
12799 /* Convert (X - c) <= X to true. */
12800 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12802 && ((code0 == MINUS_EXPR && is_positive >= 0)
12803 || (code0 == PLUS_EXPR && is_positive <= 0)))
12805 if (TREE_CODE (arg01) == INTEGER_CST
12806 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12807 fold_overflow_warning (("assuming signed overflow does not "
12808 "occur when assuming that "
12809 "(X - c) <= X is always true"),
12810 WARN_STRICT_OVERFLOW_ALL);
12811 return constant_boolean_node (1, type);
12814 /* Convert (X + c) >= X to true. */
12815 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12817 && ((code0 == PLUS_EXPR && is_positive >= 0)
12818 || (code0 == MINUS_EXPR && is_positive <= 0)))
12820 if (TREE_CODE (arg01) == INTEGER_CST
12821 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12822 fold_overflow_warning (("assuming signed overflow does not "
12823 "occur when assuming that "
12824 "(X + c) >= X is always true"),
12825 WARN_STRICT_OVERFLOW_ALL);
12826 return constant_boolean_node (1, type);
12829 if (TREE_CODE (arg01) == INTEGER_CST)
12831 /* Convert X + c > X and X - c < X to true for integers. */
12832 if (code == GT_EXPR
12833 && ((code0 == PLUS_EXPR && is_positive > 0)
12834 || (code0 == MINUS_EXPR && is_positive < 0)))
12836 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12837 fold_overflow_warning (("assuming signed overflow does "
12838 "not occur when assuming that "
12839 "(X + c) > X is always true"),
12840 WARN_STRICT_OVERFLOW_ALL);
12841 return constant_boolean_node (1, type);
12844 if (code == LT_EXPR
12845 && ((code0 == MINUS_EXPR && is_positive > 0)
12846 || (code0 == PLUS_EXPR && is_positive < 0)))
12848 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12849 fold_overflow_warning (("assuming signed overflow does "
12850 "not occur when assuming that "
12851 "(X - c) < X is always true"),
12852 WARN_STRICT_OVERFLOW_ALL);
12853 return constant_boolean_node (1, type);
12856 /* Convert X + c <= X and X - c >= X to false for integers. */
12857 if (code == LE_EXPR
12858 && ((code0 == PLUS_EXPR && is_positive > 0)
12859 || (code0 == MINUS_EXPR && is_positive < 0)))
12861 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12862 fold_overflow_warning (("assuming signed overflow does "
12863 "not occur when assuming that "
12864 "(X + c) <= X is always false"),
12865 WARN_STRICT_OVERFLOW_ALL);
12866 return constant_boolean_node (0, type);
12869 if (code == GE_EXPR
12870 && ((code0 == MINUS_EXPR && is_positive > 0)
12871 || (code0 == PLUS_EXPR && is_positive < 0)))
12873 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12874 fold_overflow_warning (("assuming signed overflow does "
12875 "not occur when assuming that "
12876 "(X - c) >= X is always false"),
12877 WARN_STRICT_OVERFLOW_ALL);
12878 return constant_boolean_node (0, type);
12883 /* Comparisons with the highest or lowest possible integer of
12884 the specified precision will have known values. */
12886 tree arg1_type = TREE_TYPE (arg1);
12887 unsigned int width = TYPE_PRECISION (arg1_type);
12889 if (TREE_CODE (arg1) == INTEGER_CST
12890 && width <= 2 * HOST_BITS_PER_WIDE_INT
12891 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12893 HOST_WIDE_INT signed_max_hi;
12894 unsigned HOST_WIDE_INT signed_max_lo;
12895 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12897 if (width <= HOST_BITS_PER_WIDE_INT)
12899 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12904 if (TYPE_UNSIGNED (arg1_type))
12906 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12912 max_lo = signed_max_lo;
12913 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12919 width -= HOST_BITS_PER_WIDE_INT;
12920 signed_max_lo = -1;
12921 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12926 if (TYPE_UNSIGNED (arg1_type))
12928 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12933 max_hi = signed_max_hi;
12934 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12938 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12939 && TREE_INT_CST_LOW (arg1) == max_lo)
12943 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12946 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12949 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12952 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
12954 /* The GE_EXPR and LT_EXPR cases above are not normally
12955 reached because of previous transformations. */
12960 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12962 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12966 arg1 = const_binop (PLUS_EXPR, arg1,
12967 build_int_cst (TREE_TYPE (arg1), 1));
12968 return fold_build2_loc (loc, EQ_EXPR, type,
12969 fold_convert_loc (loc,
12970 TREE_TYPE (arg1), arg0),
12973 arg1 = const_binop (PLUS_EXPR, arg1,
12974 build_int_cst (TREE_TYPE (arg1), 1));
12975 return fold_build2_loc (loc, NE_EXPR, type,
12976 fold_convert_loc (loc, TREE_TYPE (arg1),
12982 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12984 && TREE_INT_CST_LOW (arg1) == min_lo)
12988 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12991 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12994 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12997 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13002 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13004 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13008 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13009 return fold_build2_loc (loc, NE_EXPR, type,
13010 fold_convert_loc (loc,
13011 TREE_TYPE (arg1), arg0),
13014 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13015 return fold_build2_loc (loc, EQ_EXPR, type,
13016 fold_convert_loc (loc, TREE_TYPE (arg1),
13023 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13024 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13025 && TYPE_UNSIGNED (arg1_type)
13026 /* We will flip the signedness of the comparison operator
13027 associated with the mode of arg1, so the sign bit is
13028 specified by this mode. Check that arg1 is the signed
13029 max associated with this sign bit. */
13030 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13031 /* signed_type does not work on pointer types. */
13032 && INTEGRAL_TYPE_P (arg1_type))
13034 /* The following case also applies to X < signed_max+1
13035 and X >= signed_max+1 because previous transformations. */
13036 if (code == LE_EXPR || code == GT_EXPR)
13039 st = signed_type_for (TREE_TYPE (arg1));
13040 return fold_build2_loc (loc,
13041 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13042 type, fold_convert_loc (loc, st, arg0),
13043 build_int_cst (st, 0));
13049 /* If we are comparing an ABS_EXPR with a constant, we can
13050 convert all the cases into explicit comparisons, but they may
13051 well not be faster than doing the ABS and one comparison.
13052 But ABS (X) <= C is a range comparison, which becomes a subtraction
13053 and a comparison, and is probably faster. */
13054 if (code == LE_EXPR
13055 && TREE_CODE (arg1) == INTEGER_CST
13056 && TREE_CODE (arg0) == ABS_EXPR
13057 && ! TREE_SIDE_EFFECTS (arg0)
13058 && (0 != (tem = negate_expr (arg1)))
13059 && TREE_CODE (tem) == INTEGER_CST
13060 && !TREE_OVERFLOW (tem))
13061 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13062 build2 (GE_EXPR, type,
13063 TREE_OPERAND (arg0, 0), tem),
13064 build2 (LE_EXPR, type,
13065 TREE_OPERAND (arg0, 0), arg1));
13067 /* Convert ABS_EXPR<x> >= 0 to true. */
13068 strict_overflow_p = false;
13069 if (code == GE_EXPR
13070 && (integer_zerop (arg1)
13071 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13072 && real_zerop (arg1)))
13073 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13075 if (strict_overflow_p)
13076 fold_overflow_warning (("assuming signed overflow does not occur "
13077 "when simplifying comparison of "
13078 "absolute value and zero"),
13079 WARN_STRICT_OVERFLOW_CONDITIONAL);
13080 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13083 /* Convert ABS_EXPR<x> < 0 to false. */
13084 strict_overflow_p = false;
13085 if (code == LT_EXPR
13086 && (integer_zerop (arg1) || real_zerop (arg1))
13087 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13089 if (strict_overflow_p)
13090 fold_overflow_warning (("assuming signed overflow does not occur "
13091 "when simplifying comparison of "
13092 "absolute value and zero"),
13093 WARN_STRICT_OVERFLOW_CONDITIONAL);
13094 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13097 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13098 and similarly for >= into !=. */
13099 if ((code == LT_EXPR || code == GE_EXPR)
13100 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13101 && TREE_CODE (arg1) == LSHIFT_EXPR
13102 && integer_onep (TREE_OPERAND (arg1, 0)))
13103 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13104 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13105 TREE_OPERAND (arg1, 1)),
13106 build_int_cst (TREE_TYPE (arg0), 0));
13108 if ((code == LT_EXPR || code == GE_EXPR)
13109 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13110 && CONVERT_EXPR_P (arg1)
13111 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13112 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13114 tem = build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13115 TREE_OPERAND (TREE_OPERAND (arg1, 0), 1));
13116 return build2_loc (loc, code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13117 fold_convert_loc (loc, TREE_TYPE (arg0), tem),
13118 build_int_cst (TREE_TYPE (arg0), 0));
13123 case UNORDERED_EXPR:
13131 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13133 t1 = fold_relational_const (code, type, arg0, arg1);
13134 if (t1 != NULL_TREE)
13138 /* If the first operand is NaN, the result is constant. */
13139 if (TREE_CODE (arg0) == REAL_CST
13140 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13141 && (code != LTGT_EXPR || ! flag_trapping_math))
13143 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13144 ? integer_zero_node
13145 : integer_one_node;
13146 return omit_one_operand_loc (loc, type, t1, arg1);
13149 /* If the second operand is NaN, the result is constant. */
13150 if (TREE_CODE (arg1) == REAL_CST
13151 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13152 && (code != LTGT_EXPR || ! flag_trapping_math))
13154 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13155 ? integer_zero_node
13156 : integer_one_node;
13157 return omit_one_operand_loc (loc, type, t1, arg0);
13160 /* Simplify unordered comparison of something with itself. */
13161 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13162 && operand_equal_p (arg0, arg1, 0))
13163 return constant_boolean_node (1, type);
13165 if (code == LTGT_EXPR
13166 && !flag_trapping_math
13167 && operand_equal_p (arg0, arg1, 0))
13168 return constant_boolean_node (0, type);
13170 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13172 tree targ0 = strip_float_extensions (arg0);
13173 tree targ1 = strip_float_extensions (arg1);
13174 tree newtype = TREE_TYPE (targ0);
13176 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13177 newtype = TREE_TYPE (targ1);
13179 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13180 return fold_build2_loc (loc, code, type,
13181 fold_convert_loc (loc, newtype, targ0),
13182 fold_convert_loc (loc, newtype, targ1));
13187 case COMPOUND_EXPR:
13188 /* When pedantic, a compound expression can be neither an lvalue
13189 nor an integer constant expression. */
13190 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13192 /* Don't let (0, 0) be null pointer constant. */
13193 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13194 : fold_convert_loc (loc, type, arg1);
13195 return pedantic_non_lvalue_loc (loc, tem);
13198 if ((TREE_CODE (arg0) == REAL_CST
13199 && TREE_CODE (arg1) == REAL_CST)
13200 || (TREE_CODE (arg0) == INTEGER_CST
13201 && TREE_CODE (arg1) == INTEGER_CST))
13202 return build_complex (type, arg0, arg1);
13203 if (TREE_CODE (arg0) == REALPART_EXPR
13204 && TREE_CODE (arg1) == IMAGPART_EXPR
13205 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg0, 0)))
13206 == TYPE_MAIN_VARIANT (type))
13207 && operand_equal_p (TREE_OPERAND (arg0, 0),
13208 TREE_OPERAND (arg1, 0), 0))
13209 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
13210 TREE_OPERAND (arg1, 0));
13214 /* An ASSERT_EXPR should never be passed to fold_binary. */
13215 gcc_unreachable ();
13219 } /* switch (code) */
13222 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13223 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13227 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13229 switch (TREE_CODE (*tp))
13235 *walk_subtrees = 0;
13237 /* ... fall through ... */
13244 /* Return whether the sub-tree ST contains a label which is accessible from
13245 outside the sub-tree. */
13248 contains_label_p (tree st)
13251 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13254 /* Fold a ternary expression of code CODE and type TYPE with operands
13255 OP0, OP1, and OP2. Return the folded expression if folding is
13256 successful. Otherwise, return NULL_TREE. */
13259 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13260 tree op0, tree op1, tree op2)
13263 tree arg0 = NULL_TREE, arg1 = NULL_TREE, arg2 = NULL_TREE;
13264 enum tree_code_class kind = TREE_CODE_CLASS (code);
13266 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13267 && TREE_CODE_LENGTH (code) == 3);
13269 /* Strip any conversions that don't change the mode. This is safe
13270 for every expression, except for a comparison expression because
13271 its signedness is derived from its operands. So, in the latter
13272 case, only strip conversions that don't change the signedness.
13274 Note that this is done as an internal manipulation within the
13275 constant folder, in order to find the simplest representation of
13276 the arguments so that their form can be studied. In any cases,
13277 the appropriate type conversions should be put back in the tree
13278 that will get out of the constant folder. */
13299 case COMPONENT_REF:
13300 if (TREE_CODE (arg0) == CONSTRUCTOR
13301 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13303 unsigned HOST_WIDE_INT idx;
13305 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13312 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13313 so all simple results must be passed through pedantic_non_lvalue. */
13314 if (TREE_CODE (arg0) == INTEGER_CST)
13316 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13317 tem = integer_zerop (arg0) ? op2 : op1;
13318 /* Only optimize constant conditions when the selected branch
13319 has the same type as the COND_EXPR. This avoids optimizing
13320 away "c ? x : throw", where the throw has a void type.
13321 Avoid throwing away that operand which contains label. */
13322 if ((!TREE_SIDE_EFFECTS (unused_op)
13323 || !contains_label_p (unused_op))
13324 && (! VOID_TYPE_P (TREE_TYPE (tem))
13325 || VOID_TYPE_P (type)))
13326 return pedantic_non_lvalue_loc (loc, tem);
13329 if (operand_equal_p (arg1, op2, 0))
13330 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13332 /* If we have A op B ? A : C, we may be able to convert this to a
13333 simpler expression, depending on the operation and the values
13334 of B and C. Signed zeros prevent all of these transformations,
13335 for reasons given above each one.
13337 Also try swapping the arguments and inverting the conditional. */
13338 if (COMPARISON_CLASS_P (arg0)
13339 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13340 arg1, TREE_OPERAND (arg0, 1))
13341 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13343 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13348 if (COMPARISON_CLASS_P (arg0)
13349 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13351 TREE_OPERAND (arg0, 1))
13352 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13354 location_t loc0 = expr_location_or (arg0, loc);
13355 tem = fold_truth_not_expr (loc0, arg0);
13356 if (tem && COMPARISON_CLASS_P (tem))
13358 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13364 /* If the second operand is simpler than the third, swap them
13365 since that produces better jump optimization results. */
13366 if (truth_value_p (TREE_CODE (arg0))
13367 && tree_swap_operands_p (op1, op2, false))
13369 location_t loc0 = expr_location_or (arg0, loc);
13370 /* See if this can be inverted. If it can't, possibly because
13371 it was a floating-point inequality comparison, don't do
13373 tem = fold_truth_not_expr (loc0, arg0);
13375 return fold_build3_loc (loc, code, type, tem, op2, op1);
13378 /* Convert A ? 1 : 0 to simply A. */
13379 if (integer_onep (op1)
13380 && integer_zerop (op2)
13381 /* If we try to convert OP0 to our type, the
13382 call to fold will try to move the conversion inside
13383 a COND, which will recurse. In that case, the COND_EXPR
13384 is probably the best choice, so leave it alone. */
13385 && type == TREE_TYPE (arg0))
13386 return pedantic_non_lvalue_loc (loc, arg0);
13388 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13389 over COND_EXPR in cases such as floating point comparisons. */
13390 if (integer_zerop (op1)
13391 && integer_onep (op2)
13392 && truth_value_p (TREE_CODE (arg0)))
13393 return pedantic_non_lvalue_loc (loc,
13394 fold_convert_loc (loc, type,
13395 invert_truthvalue_loc (loc,
13398 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13399 if (TREE_CODE (arg0) == LT_EXPR
13400 && integer_zerop (TREE_OPERAND (arg0, 1))
13401 && integer_zerop (op2)
13402 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13404 /* sign_bit_p only checks ARG1 bits within A's precision.
13405 If <sign bit of A> has wider type than A, bits outside
13406 of A's precision in <sign bit of A> need to be checked.
13407 If they are all 0, this optimization needs to be done
13408 in unsigned A's type, if they are all 1 in signed A's type,
13409 otherwise this can't be done. */
13410 if (TYPE_PRECISION (TREE_TYPE (tem))
13411 < TYPE_PRECISION (TREE_TYPE (arg1))
13412 && TYPE_PRECISION (TREE_TYPE (tem))
13413 < TYPE_PRECISION (type))
13415 unsigned HOST_WIDE_INT mask_lo;
13416 HOST_WIDE_INT mask_hi;
13417 int inner_width, outer_width;
13420 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13421 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13422 if (outer_width > TYPE_PRECISION (type))
13423 outer_width = TYPE_PRECISION (type);
13425 if (outer_width > HOST_BITS_PER_WIDE_INT)
13427 mask_hi = ((unsigned HOST_WIDE_INT) -1
13428 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13434 mask_lo = ((unsigned HOST_WIDE_INT) -1
13435 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13437 if (inner_width > HOST_BITS_PER_WIDE_INT)
13439 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13440 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13444 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13445 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13447 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13448 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13450 tem_type = signed_type_for (TREE_TYPE (tem));
13451 tem = fold_convert_loc (loc, tem_type, tem);
13453 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13454 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13456 tem_type = unsigned_type_for (TREE_TYPE (tem));
13457 tem = fold_convert_loc (loc, tem_type, tem);
13465 fold_convert_loc (loc, type,
13466 fold_build2_loc (loc, BIT_AND_EXPR,
13467 TREE_TYPE (tem), tem,
13468 fold_convert_loc (loc,
13473 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13474 already handled above. */
13475 if (TREE_CODE (arg0) == BIT_AND_EXPR
13476 && integer_onep (TREE_OPERAND (arg0, 1))
13477 && integer_zerop (op2)
13478 && integer_pow2p (arg1))
13480 tree tem = TREE_OPERAND (arg0, 0);
13482 if (TREE_CODE (tem) == RSHIFT_EXPR
13483 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13484 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13485 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13486 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13487 TREE_OPERAND (tem, 0), arg1);
13490 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13491 is probably obsolete because the first operand should be a
13492 truth value (that's why we have the two cases above), but let's
13493 leave it in until we can confirm this for all front-ends. */
13494 if (integer_zerop (op2)
13495 && TREE_CODE (arg0) == NE_EXPR
13496 && integer_zerop (TREE_OPERAND (arg0, 1))
13497 && integer_pow2p (arg1)
13498 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13499 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13500 arg1, OEP_ONLY_CONST))
13501 return pedantic_non_lvalue_loc (loc,
13502 fold_convert_loc (loc, type,
13503 TREE_OPERAND (arg0, 0)));
13505 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13506 if (integer_zerop (op2)
13507 && truth_value_p (TREE_CODE (arg0))
13508 && truth_value_p (TREE_CODE (arg1)))
13509 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13510 fold_convert_loc (loc, type, arg0),
13513 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13514 if (integer_onep (op2)
13515 && truth_value_p (TREE_CODE (arg0))
13516 && truth_value_p (TREE_CODE (arg1)))
13518 location_t loc0 = expr_location_or (arg0, loc);
13519 /* Only perform transformation if ARG0 is easily inverted. */
13520 tem = fold_truth_not_expr (loc0, arg0);
13522 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13523 fold_convert_loc (loc, type, tem),
13527 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13528 if (integer_zerop (arg1)
13529 && truth_value_p (TREE_CODE (arg0))
13530 && truth_value_p (TREE_CODE (op2)))
13532 location_t loc0 = expr_location_or (arg0, loc);
13533 /* Only perform transformation if ARG0 is easily inverted. */
13534 tem = fold_truth_not_expr (loc0, arg0);
13536 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13537 fold_convert_loc (loc, type, tem),
13541 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13542 if (integer_onep (arg1)
13543 && truth_value_p (TREE_CODE (arg0))
13544 && truth_value_p (TREE_CODE (op2)))
13545 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13546 fold_convert_loc (loc, type, arg0),
13552 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13553 of fold_ternary on them. */
13554 gcc_unreachable ();
13556 case BIT_FIELD_REF:
13557 if ((TREE_CODE (arg0) == VECTOR_CST
13558 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13559 && type == TREE_TYPE (TREE_TYPE (arg0)))
13561 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13562 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13565 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13566 && (idx % width) == 0
13567 && (idx = idx / width)
13568 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13570 tree elements = NULL_TREE;
13572 if (TREE_CODE (arg0) == VECTOR_CST)
13573 elements = TREE_VECTOR_CST_ELTS (arg0);
13576 unsigned HOST_WIDE_INT idx;
13579 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13580 elements = tree_cons (NULL_TREE, value, elements);
13582 while (idx-- > 0 && elements)
13583 elements = TREE_CHAIN (elements);
13585 return TREE_VALUE (elements);
13587 return build_zero_cst (type);
13591 /* A bit-field-ref that referenced the full argument can be stripped. */
13592 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13593 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13594 && integer_zerop (op2))
13595 return fold_convert_loc (loc, type, arg0);
13600 /* For integers we can decompose the FMA if possible. */
13601 if (TREE_CODE (arg0) == INTEGER_CST
13602 && TREE_CODE (arg1) == INTEGER_CST)
13603 return fold_build2_loc (loc, PLUS_EXPR, type,
13604 const_binop (MULT_EXPR, arg0, arg1), arg2);
13605 if (integer_zerop (arg2))
13606 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
13608 return fold_fma (loc, type, arg0, arg1, arg2);
13612 } /* switch (code) */
13615 /* Perform constant folding and related simplification of EXPR.
13616 The related simplifications include x*1 => x, x*0 => 0, etc.,
13617 and application of the associative law.
13618 NOP_EXPR conversions may be removed freely (as long as we
13619 are careful not to change the type of the overall expression).
13620 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13621 but we can constant-fold them if they have constant operands. */
13623 #ifdef ENABLE_FOLD_CHECKING
13624 # define fold(x) fold_1 (x)
13625 static tree fold_1 (tree);
13631 const tree t = expr;
13632 enum tree_code code = TREE_CODE (t);
13633 enum tree_code_class kind = TREE_CODE_CLASS (code);
13635 location_t loc = EXPR_LOCATION (expr);
13637 /* Return right away if a constant. */
13638 if (kind == tcc_constant)
13641 /* CALL_EXPR-like objects with variable numbers of operands are
13642 treated specially. */
13643 if (kind == tcc_vl_exp)
13645 if (code == CALL_EXPR)
13647 tem = fold_call_expr (loc, expr, false);
13648 return tem ? tem : expr;
13653 if (IS_EXPR_CODE_CLASS (kind))
13655 tree type = TREE_TYPE (t);
13656 tree op0, op1, op2;
13658 switch (TREE_CODE_LENGTH (code))
13661 op0 = TREE_OPERAND (t, 0);
13662 tem = fold_unary_loc (loc, code, type, op0);
13663 return tem ? tem : expr;
13665 op0 = TREE_OPERAND (t, 0);
13666 op1 = TREE_OPERAND (t, 1);
13667 tem = fold_binary_loc (loc, code, type, op0, op1);
13668 return tem ? tem : expr;
13670 op0 = TREE_OPERAND (t, 0);
13671 op1 = TREE_OPERAND (t, 1);
13672 op2 = TREE_OPERAND (t, 2);
13673 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
13674 return tem ? tem : expr;
13684 tree op0 = TREE_OPERAND (t, 0);
13685 tree op1 = TREE_OPERAND (t, 1);
13687 if (TREE_CODE (op1) == INTEGER_CST
13688 && TREE_CODE (op0) == CONSTRUCTOR
13689 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13691 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13692 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13693 unsigned HOST_WIDE_INT begin = 0;
13695 /* Find a matching index by means of a binary search. */
13696 while (begin != end)
13698 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13699 tree index = VEC_index (constructor_elt, elts, middle)->index;
13701 if (TREE_CODE (index) == INTEGER_CST
13702 && tree_int_cst_lt (index, op1))
13703 begin = middle + 1;
13704 else if (TREE_CODE (index) == INTEGER_CST
13705 && tree_int_cst_lt (op1, index))
13707 else if (TREE_CODE (index) == RANGE_EXPR
13708 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13709 begin = middle + 1;
13710 else if (TREE_CODE (index) == RANGE_EXPR
13711 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13714 return VEC_index (constructor_elt, elts, middle)->value;
13722 return fold (DECL_INITIAL (t));
13726 } /* switch (code) */
13729 #ifdef ENABLE_FOLD_CHECKING
13732 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13733 static void fold_check_failed (const_tree, const_tree);
13734 void print_fold_checksum (const_tree);
13736 /* When --enable-checking=fold, compute a digest of expr before
13737 and after actual fold call to see if fold did not accidentally
13738 change original expr. */
13744 struct md5_ctx ctx;
13745 unsigned char checksum_before[16], checksum_after[16];
13748 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13749 md5_init_ctx (&ctx);
13750 fold_checksum_tree (expr, &ctx, ht);
13751 md5_finish_ctx (&ctx, checksum_before);
13754 ret = fold_1 (expr);
13756 md5_init_ctx (&ctx);
13757 fold_checksum_tree (expr, &ctx, ht);
13758 md5_finish_ctx (&ctx, checksum_after);
13761 if (memcmp (checksum_before, checksum_after, 16))
13762 fold_check_failed (expr, ret);
13768 print_fold_checksum (const_tree expr)
13770 struct md5_ctx ctx;
13771 unsigned char checksum[16], cnt;
13774 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13775 md5_init_ctx (&ctx);
13776 fold_checksum_tree (expr, &ctx, ht);
13777 md5_finish_ctx (&ctx, checksum);
13779 for (cnt = 0; cnt < 16; ++cnt)
13780 fprintf (stderr, "%02x", checksum[cnt]);
13781 putc ('\n', stderr);
13785 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13787 internal_error ("fold check: original tree changed by fold");
13791 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13794 enum tree_code code;
13795 union tree_node buf;
13800 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13801 <= sizeof (struct tree_function_decl))
13802 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13805 slot = (void **) htab_find_slot (ht, expr, INSERT);
13808 *slot = CONST_CAST_TREE (expr);
13809 code = TREE_CODE (expr);
13810 if (TREE_CODE_CLASS (code) == tcc_declaration
13811 && DECL_ASSEMBLER_NAME_SET_P (expr))
13813 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13814 memcpy ((char *) &buf, expr, tree_size (expr));
13815 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13816 expr = (tree) &buf;
13818 else if (TREE_CODE_CLASS (code) == tcc_type
13819 && (TYPE_POINTER_TO (expr)
13820 || TYPE_REFERENCE_TO (expr)
13821 || TYPE_CACHED_VALUES_P (expr)
13822 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13823 || TYPE_NEXT_VARIANT (expr)))
13825 /* Allow these fields to be modified. */
13827 memcpy ((char *) &buf, expr, tree_size (expr));
13828 expr = tmp = (tree) &buf;
13829 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13830 TYPE_POINTER_TO (tmp) = NULL;
13831 TYPE_REFERENCE_TO (tmp) = NULL;
13832 TYPE_NEXT_VARIANT (tmp) = NULL;
13833 if (TYPE_CACHED_VALUES_P (tmp))
13835 TYPE_CACHED_VALUES_P (tmp) = 0;
13836 TYPE_CACHED_VALUES (tmp) = NULL;
13839 md5_process_bytes (expr, tree_size (expr), ctx);
13840 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13841 if (TREE_CODE_CLASS (code) != tcc_type
13842 && TREE_CODE_CLASS (code) != tcc_declaration
13843 && code != TREE_LIST
13844 && code != SSA_NAME
13845 && CODE_CONTAINS_STRUCT (code, TS_COMMON))
13846 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13847 switch (TREE_CODE_CLASS (code))
13853 md5_process_bytes (TREE_STRING_POINTER (expr),
13854 TREE_STRING_LENGTH (expr), ctx);
13857 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13858 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13861 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13867 case tcc_exceptional:
13871 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13872 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13873 expr = TREE_CHAIN (expr);
13874 goto recursive_label;
13877 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13878 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13884 case tcc_expression:
13885 case tcc_reference:
13886 case tcc_comparison:
13889 case tcc_statement:
13891 len = TREE_OPERAND_LENGTH (expr);
13892 for (i = 0; i < len; ++i)
13893 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13895 case tcc_declaration:
13896 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13897 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13898 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13900 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13901 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13902 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13903 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13904 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13906 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13907 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13909 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13911 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13912 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13913 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13917 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13918 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13919 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13920 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13921 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13922 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13923 if (INTEGRAL_TYPE_P (expr)
13924 || SCALAR_FLOAT_TYPE_P (expr))
13926 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13927 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13929 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13930 if (TREE_CODE (expr) == RECORD_TYPE
13931 || TREE_CODE (expr) == UNION_TYPE
13932 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13933 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13934 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13941 /* Helper function for outputting the checksum of a tree T. When
13942 debugging with gdb, you can "define mynext" to be "next" followed
13943 by "call debug_fold_checksum (op0)", then just trace down till the
13946 DEBUG_FUNCTION void
13947 debug_fold_checksum (const_tree t)
13950 unsigned char checksum[16];
13951 struct md5_ctx ctx;
13952 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13954 md5_init_ctx (&ctx);
13955 fold_checksum_tree (t, &ctx, ht);
13956 md5_finish_ctx (&ctx, checksum);
13959 for (i = 0; i < 16; i++)
13960 fprintf (stderr, "%d ", checksum[i]);
13962 fprintf (stderr, "\n");
13967 /* Fold a unary tree expression with code CODE of type TYPE with an
13968 operand OP0. LOC is the location of the resulting expression.
13969 Return a folded expression if successful. Otherwise, return a tree
13970 expression with code CODE of type TYPE with an operand OP0. */
13973 fold_build1_stat_loc (location_t loc,
13974 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13977 #ifdef ENABLE_FOLD_CHECKING
13978 unsigned char checksum_before[16], checksum_after[16];
13979 struct md5_ctx ctx;
13982 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13983 md5_init_ctx (&ctx);
13984 fold_checksum_tree (op0, &ctx, ht);
13985 md5_finish_ctx (&ctx, checksum_before);
13989 tem = fold_unary_loc (loc, code, type, op0);
13991 tem = build1_stat_loc (loc, code, type, op0 PASS_MEM_STAT);
13993 #ifdef ENABLE_FOLD_CHECKING
13994 md5_init_ctx (&ctx);
13995 fold_checksum_tree (op0, &ctx, ht);
13996 md5_finish_ctx (&ctx, checksum_after);
13999 if (memcmp (checksum_before, checksum_after, 16))
14000 fold_check_failed (op0, tem);
14005 /* Fold a binary tree expression with code CODE of type TYPE with
14006 operands OP0 and OP1. LOC is the location of the resulting
14007 expression. Return a folded expression if successful. Otherwise,
14008 return a tree expression with code CODE of type TYPE with operands
14012 fold_build2_stat_loc (location_t loc,
14013 enum tree_code code, tree type, tree op0, tree op1
14017 #ifdef ENABLE_FOLD_CHECKING
14018 unsigned char checksum_before_op0[16],
14019 checksum_before_op1[16],
14020 checksum_after_op0[16],
14021 checksum_after_op1[16];
14022 struct md5_ctx ctx;
14025 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14026 md5_init_ctx (&ctx);
14027 fold_checksum_tree (op0, &ctx, ht);
14028 md5_finish_ctx (&ctx, checksum_before_op0);
14031 md5_init_ctx (&ctx);
14032 fold_checksum_tree (op1, &ctx, ht);
14033 md5_finish_ctx (&ctx, checksum_before_op1);
14037 tem = fold_binary_loc (loc, code, type, op0, op1);
14039 tem = build2_stat_loc (loc, code, type, op0, op1 PASS_MEM_STAT);
14041 #ifdef ENABLE_FOLD_CHECKING
14042 md5_init_ctx (&ctx);
14043 fold_checksum_tree (op0, &ctx, ht);
14044 md5_finish_ctx (&ctx, checksum_after_op0);
14047 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14048 fold_check_failed (op0, tem);
14050 md5_init_ctx (&ctx);
14051 fold_checksum_tree (op1, &ctx, ht);
14052 md5_finish_ctx (&ctx, checksum_after_op1);
14055 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14056 fold_check_failed (op1, tem);
14061 /* Fold a ternary tree expression with code CODE of type TYPE with
14062 operands OP0, OP1, and OP2. Return a folded expression if
14063 successful. Otherwise, return a tree expression with code CODE of
14064 type TYPE with operands OP0, OP1, and OP2. */
14067 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14068 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14071 #ifdef ENABLE_FOLD_CHECKING
14072 unsigned char checksum_before_op0[16],
14073 checksum_before_op1[16],
14074 checksum_before_op2[16],
14075 checksum_after_op0[16],
14076 checksum_after_op1[16],
14077 checksum_after_op2[16];
14078 struct md5_ctx ctx;
14081 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14082 md5_init_ctx (&ctx);
14083 fold_checksum_tree (op0, &ctx, ht);
14084 md5_finish_ctx (&ctx, checksum_before_op0);
14087 md5_init_ctx (&ctx);
14088 fold_checksum_tree (op1, &ctx, ht);
14089 md5_finish_ctx (&ctx, checksum_before_op1);
14092 md5_init_ctx (&ctx);
14093 fold_checksum_tree (op2, &ctx, ht);
14094 md5_finish_ctx (&ctx, checksum_before_op2);
14098 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14099 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14101 tem = build3_stat_loc (loc, code, type, op0, op1, op2 PASS_MEM_STAT);
14103 #ifdef ENABLE_FOLD_CHECKING
14104 md5_init_ctx (&ctx);
14105 fold_checksum_tree (op0, &ctx, ht);
14106 md5_finish_ctx (&ctx, checksum_after_op0);
14109 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14110 fold_check_failed (op0, tem);
14112 md5_init_ctx (&ctx);
14113 fold_checksum_tree (op1, &ctx, ht);
14114 md5_finish_ctx (&ctx, checksum_after_op1);
14117 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14118 fold_check_failed (op1, tem);
14120 md5_init_ctx (&ctx);
14121 fold_checksum_tree (op2, &ctx, ht);
14122 md5_finish_ctx (&ctx, checksum_after_op2);
14125 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14126 fold_check_failed (op2, tem);
14131 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14132 arguments in ARGARRAY, and a null static chain.
14133 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14134 of type TYPE from the given operands as constructed by build_call_array. */
14137 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14138 int nargs, tree *argarray)
14141 #ifdef ENABLE_FOLD_CHECKING
14142 unsigned char checksum_before_fn[16],
14143 checksum_before_arglist[16],
14144 checksum_after_fn[16],
14145 checksum_after_arglist[16];
14146 struct md5_ctx ctx;
14150 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14151 md5_init_ctx (&ctx);
14152 fold_checksum_tree (fn, &ctx, ht);
14153 md5_finish_ctx (&ctx, checksum_before_fn);
14156 md5_init_ctx (&ctx);
14157 for (i = 0; i < nargs; i++)
14158 fold_checksum_tree (argarray[i], &ctx, ht);
14159 md5_finish_ctx (&ctx, checksum_before_arglist);
14163 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14165 #ifdef ENABLE_FOLD_CHECKING
14166 md5_init_ctx (&ctx);
14167 fold_checksum_tree (fn, &ctx, ht);
14168 md5_finish_ctx (&ctx, checksum_after_fn);
14171 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14172 fold_check_failed (fn, tem);
14174 md5_init_ctx (&ctx);
14175 for (i = 0; i < nargs; i++)
14176 fold_checksum_tree (argarray[i], &ctx, ht);
14177 md5_finish_ctx (&ctx, checksum_after_arglist);
14180 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14181 fold_check_failed (NULL_TREE, tem);
14186 /* Perform constant folding and related simplification of initializer
14187 expression EXPR. These behave identically to "fold_buildN" but ignore
14188 potential run-time traps and exceptions that fold must preserve. */
14190 #define START_FOLD_INIT \
14191 int saved_signaling_nans = flag_signaling_nans;\
14192 int saved_trapping_math = flag_trapping_math;\
14193 int saved_rounding_math = flag_rounding_math;\
14194 int saved_trapv = flag_trapv;\
14195 int saved_folding_initializer = folding_initializer;\
14196 flag_signaling_nans = 0;\
14197 flag_trapping_math = 0;\
14198 flag_rounding_math = 0;\
14200 folding_initializer = 1;
14202 #define END_FOLD_INIT \
14203 flag_signaling_nans = saved_signaling_nans;\
14204 flag_trapping_math = saved_trapping_math;\
14205 flag_rounding_math = saved_rounding_math;\
14206 flag_trapv = saved_trapv;\
14207 folding_initializer = saved_folding_initializer;
14210 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14211 tree type, tree op)
14216 result = fold_build1_loc (loc, code, type, op);
14223 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14224 tree type, tree op0, tree op1)
14229 result = fold_build2_loc (loc, code, type, op0, op1);
14236 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14237 tree type, tree op0, tree op1, tree op2)
14242 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14249 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14250 int nargs, tree *argarray)
14255 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14261 #undef START_FOLD_INIT
14262 #undef END_FOLD_INIT
14264 /* Determine if first argument is a multiple of second argument. Return 0 if
14265 it is not, or we cannot easily determined it to be.
14267 An example of the sort of thing we care about (at this point; this routine
14268 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14269 fold cases do now) is discovering that
14271 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14277 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14279 This code also handles discovering that
14281 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14283 is a multiple of 8 so we don't have to worry about dealing with a
14284 possible remainder.
14286 Note that we *look* inside a SAVE_EXPR only to determine how it was
14287 calculated; it is not safe for fold to do much of anything else with the
14288 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14289 at run time. For example, the latter example above *cannot* be implemented
14290 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14291 evaluation time of the original SAVE_EXPR is not necessarily the same at
14292 the time the new expression is evaluated. The only optimization of this
14293 sort that would be valid is changing
14295 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14299 SAVE_EXPR (I) * SAVE_EXPR (J)
14301 (where the same SAVE_EXPR (J) is used in the original and the
14302 transformed version). */
14305 multiple_of_p (tree type, const_tree top, const_tree bottom)
14307 if (operand_equal_p (top, bottom, 0))
14310 if (TREE_CODE (type) != INTEGER_TYPE)
14313 switch (TREE_CODE (top))
14316 /* Bitwise and provides a power of two multiple. If the mask is
14317 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14318 if (!integer_pow2p (bottom))
14323 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14324 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14328 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14329 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14332 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14336 op1 = TREE_OPERAND (top, 1);
14337 /* const_binop may not detect overflow correctly,
14338 so check for it explicitly here. */
14339 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14340 > TREE_INT_CST_LOW (op1)
14341 && TREE_INT_CST_HIGH (op1) == 0
14342 && 0 != (t1 = fold_convert (type,
14343 const_binop (LSHIFT_EXPR,
14346 && !TREE_OVERFLOW (t1))
14347 return multiple_of_p (type, t1, bottom);
14352 /* Can't handle conversions from non-integral or wider integral type. */
14353 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14354 || (TYPE_PRECISION (type)
14355 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14358 /* .. fall through ... */
14361 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14364 return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
14365 && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
14368 if (TREE_CODE (bottom) != INTEGER_CST
14369 || integer_zerop (bottom)
14370 || (TYPE_UNSIGNED (type)
14371 && (tree_int_cst_sgn (top) < 0
14372 || tree_int_cst_sgn (bottom) < 0)))
14374 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14382 /* Return true if CODE or TYPE is known to be non-negative. */
14385 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14387 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14388 && truth_value_p (code))
14389 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14390 have a signed:1 type (where the value is -1 and 0). */
14395 /* Return true if (CODE OP0) is known to be non-negative. If the return
14396 value is based on the assumption that signed overflow is undefined,
14397 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14398 *STRICT_OVERFLOW_P. */
14401 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14402 bool *strict_overflow_p)
14404 if (TYPE_UNSIGNED (type))
14410 /* We can't return 1 if flag_wrapv is set because
14411 ABS_EXPR<INT_MIN> = INT_MIN. */
14412 if (!INTEGRAL_TYPE_P (type))
14414 if (TYPE_OVERFLOW_UNDEFINED (type))
14416 *strict_overflow_p = true;
14421 case NON_LVALUE_EXPR:
14423 case FIX_TRUNC_EXPR:
14424 return tree_expr_nonnegative_warnv_p (op0,
14425 strict_overflow_p);
14429 tree inner_type = TREE_TYPE (op0);
14430 tree outer_type = type;
14432 if (TREE_CODE (outer_type) == REAL_TYPE)
14434 if (TREE_CODE (inner_type) == REAL_TYPE)
14435 return tree_expr_nonnegative_warnv_p (op0,
14436 strict_overflow_p);
14437 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14439 if (TYPE_UNSIGNED (inner_type))
14441 return tree_expr_nonnegative_warnv_p (op0,
14442 strict_overflow_p);
14445 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14447 if (TREE_CODE (inner_type) == REAL_TYPE)
14448 return tree_expr_nonnegative_warnv_p (op0,
14449 strict_overflow_p);
14450 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14451 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14452 && TYPE_UNSIGNED (inner_type);
14458 return tree_simple_nonnegative_warnv_p (code, type);
14461 /* We don't know sign of `t', so be conservative and return false. */
14465 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14466 value is based on the assumption that signed overflow is undefined,
14467 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14468 *STRICT_OVERFLOW_P. */
14471 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14472 tree op1, bool *strict_overflow_p)
14474 if (TYPE_UNSIGNED (type))
14479 case POINTER_PLUS_EXPR:
14481 if (FLOAT_TYPE_P (type))
14482 return (tree_expr_nonnegative_warnv_p (op0,
14484 && tree_expr_nonnegative_warnv_p (op1,
14485 strict_overflow_p));
14487 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14488 both unsigned and at least 2 bits shorter than the result. */
14489 if (TREE_CODE (type) == INTEGER_TYPE
14490 && TREE_CODE (op0) == NOP_EXPR
14491 && TREE_CODE (op1) == NOP_EXPR)
14493 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14494 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14495 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14496 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14498 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14499 TYPE_PRECISION (inner2)) + 1;
14500 return prec < TYPE_PRECISION (type);
14506 if (FLOAT_TYPE_P (type))
14508 /* x * x for floating point x is always non-negative. */
14509 if (operand_equal_p (op0, op1, 0))
14511 return (tree_expr_nonnegative_warnv_p (op0,
14513 && tree_expr_nonnegative_warnv_p (op1,
14514 strict_overflow_p));
14517 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14518 both unsigned and their total bits is shorter than the result. */
14519 if (TREE_CODE (type) == INTEGER_TYPE
14520 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14521 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14523 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14524 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14526 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14527 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14530 bool unsigned0 = TYPE_UNSIGNED (inner0);
14531 bool unsigned1 = TYPE_UNSIGNED (inner1);
14533 if (TREE_CODE (op0) == INTEGER_CST)
14534 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14536 if (TREE_CODE (op1) == INTEGER_CST)
14537 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14539 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14540 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14542 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14543 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14544 : TYPE_PRECISION (inner0);
14546 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14547 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14548 : TYPE_PRECISION (inner1);
14550 return precision0 + precision1 < TYPE_PRECISION (type);
14557 return (tree_expr_nonnegative_warnv_p (op0,
14559 || tree_expr_nonnegative_warnv_p (op1,
14560 strict_overflow_p));
14566 case TRUNC_DIV_EXPR:
14567 case CEIL_DIV_EXPR:
14568 case FLOOR_DIV_EXPR:
14569 case ROUND_DIV_EXPR:
14570 return (tree_expr_nonnegative_warnv_p (op0,
14572 && tree_expr_nonnegative_warnv_p (op1,
14573 strict_overflow_p));
14575 case TRUNC_MOD_EXPR:
14576 case CEIL_MOD_EXPR:
14577 case FLOOR_MOD_EXPR:
14578 case ROUND_MOD_EXPR:
14579 return tree_expr_nonnegative_warnv_p (op0,
14580 strict_overflow_p);
14582 return tree_simple_nonnegative_warnv_p (code, type);
14585 /* We don't know sign of `t', so be conservative and return false. */
14589 /* Return true if T is known to be non-negative. If the return
14590 value is based on the assumption that signed overflow is undefined,
14591 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14592 *STRICT_OVERFLOW_P. */
14595 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14597 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14600 switch (TREE_CODE (t))
14603 return tree_int_cst_sgn (t) >= 0;
14606 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14609 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14612 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14614 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14615 strict_overflow_p));
14617 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14620 /* We don't know sign of `t', so be conservative and return false. */
14624 /* Return true if T is known to be non-negative. If the return
14625 value is based on the assumption that signed overflow is undefined,
14626 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14627 *STRICT_OVERFLOW_P. */
14630 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14631 tree arg0, tree arg1, bool *strict_overflow_p)
14633 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14634 switch (DECL_FUNCTION_CODE (fndecl))
14636 CASE_FLT_FN (BUILT_IN_ACOS):
14637 CASE_FLT_FN (BUILT_IN_ACOSH):
14638 CASE_FLT_FN (BUILT_IN_CABS):
14639 CASE_FLT_FN (BUILT_IN_COSH):
14640 CASE_FLT_FN (BUILT_IN_ERFC):
14641 CASE_FLT_FN (BUILT_IN_EXP):
14642 CASE_FLT_FN (BUILT_IN_EXP10):
14643 CASE_FLT_FN (BUILT_IN_EXP2):
14644 CASE_FLT_FN (BUILT_IN_FABS):
14645 CASE_FLT_FN (BUILT_IN_FDIM):
14646 CASE_FLT_FN (BUILT_IN_HYPOT):
14647 CASE_FLT_FN (BUILT_IN_POW10):
14648 CASE_INT_FN (BUILT_IN_FFS):
14649 CASE_INT_FN (BUILT_IN_PARITY):
14650 CASE_INT_FN (BUILT_IN_POPCOUNT):
14651 case BUILT_IN_BSWAP32:
14652 case BUILT_IN_BSWAP64:
14656 CASE_FLT_FN (BUILT_IN_SQRT):
14657 /* sqrt(-0.0) is -0.0. */
14658 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14660 return tree_expr_nonnegative_warnv_p (arg0,
14661 strict_overflow_p);
14663 CASE_FLT_FN (BUILT_IN_ASINH):
14664 CASE_FLT_FN (BUILT_IN_ATAN):
14665 CASE_FLT_FN (BUILT_IN_ATANH):
14666 CASE_FLT_FN (BUILT_IN_CBRT):
14667 CASE_FLT_FN (BUILT_IN_CEIL):
14668 CASE_FLT_FN (BUILT_IN_ERF):
14669 CASE_FLT_FN (BUILT_IN_EXPM1):
14670 CASE_FLT_FN (BUILT_IN_FLOOR):
14671 CASE_FLT_FN (BUILT_IN_FMOD):
14672 CASE_FLT_FN (BUILT_IN_FREXP):
14673 CASE_FLT_FN (BUILT_IN_LCEIL):
14674 CASE_FLT_FN (BUILT_IN_LDEXP):
14675 CASE_FLT_FN (BUILT_IN_LFLOOR):
14676 CASE_FLT_FN (BUILT_IN_LLCEIL):
14677 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14678 CASE_FLT_FN (BUILT_IN_LLRINT):
14679 CASE_FLT_FN (BUILT_IN_LLROUND):
14680 CASE_FLT_FN (BUILT_IN_LRINT):
14681 CASE_FLT_FN (BUILT_IN_LROUND):
14682 CASE_FLT_FN (BUILT_IN_MODF):
14683 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14684 CASE_FLT_FN (BUILT_IN_RINT):
14685 CASE_FLT_FN (BUILT_IN_ROUND):
14686 CASE_FLT_FN (BUILT_IN_SCALB):
14687 CASE_FLT_FN (BUILT_IN_SCALBLN):
14688 CASE_FLT_FN (BUILT_IN_SCALBN):
14689 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14690 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14691 CASE_FLT_FN (BUILT_IN_SINH):
14692 CASE_FLT_FN (BUILT_IN_TANH):
14693 CASE_FLT_FN (BUILT_IN_TRUNC):
14694 /* True if the 1st argument is nonnegative. */
14695 return tree_expr_nonnegative_warnv_p (arg0,
14696 strict_overflow_p);
14698 CASE_FLT_FN (BUILT_IN_FMAX):
14699 /* True if the 1st OR 2nd arguments are nonnegative. */
14700 return (tree_expr_nonnegative_warnv_p (arg0,
14702 || (tree_expr_nonnegative_warnv_p (arg1,
14703 strict_overflow_p)));
14705 CASE_FLT_FN (BUILT_IN_FMIN):
14706 /* True if the 1st AND 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_COPYSIGN):
14713 /* True if the 2nd argument is nonnegative. */
14714 return tree_expr_nonnegative_warnv_p (arg1,
14715 strict_overflow_p);
14717 CASE_FLT_FN (BUILT_IN_POWI):
14718 /* True if the 1st argument is nonnegative or the second
14719 argument is an even integer. */
14720 if (TREE_CODE (arg1) == INTEGER_CST
14721 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14723 return tree_expr_nonnegative_warnv_p (arg0,
14724 strict_overflow_p);
14726 CASE_FLT_FN (BUILT_IN_POW):
14727 /* True if the 1st argument is nonnegative or the second
14728 argument is an even integer valued real. */
14729 if (TREE_CODE (arg1) == REAL_CST)
14734 c = TREE_REAL_CST (arg1);
14735 n = real_to_integer (&c);
14738 REAL_VALUE_TYPE cint;
14739 real_from_integer (&cint, VOIDmode, n,
14740 n < 0 ? -1 : 0, 0);
14741 if (real_identical (&c, &cint))
14745 return tree_expr_nonnegative_warnv_p (arg0,
14746 strict_overflow_p);
14751 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14755 /* Return true if T is known to be non-negative. If the return
14756 value is based on the assumption that signed overflow is undefined,
14757 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14758 *STRICT_OVERFLOW_P. */
14761 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14763 enum tree_code code = TREE_CODE (t);
14764 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14771 tree temp = TARGET_EXPR_SLOT (t);
14772 t = TARGET_EXPR_INITIAL (t);
14774 /* If the initializer is non-void, then it's a normal expression
14775 that will be assigned to the slot. */
14776 if (!VOID_TYPE_P (t))
14777 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14779 /* Otherwise, the initializer sets the slot in some way. One common
14780 way is an assignment statement at the end of the initializer. */
14783 if (TREE_CODE (t) == BIND_EXPR)
14784 t = expr_last (BIND_EXPR_BODY (t));
14785 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14786 || TREE_CODE (t) == TRY_CATCH_EXPR)
14787 t = expr_last (TREE_OPERAND (t, 0));
14788 else if (TREE_CODE (t) == STATEMENT_LIST)
14793 if (TREE_CODE (t) == MODIFY_EXPR
14794 && TREE_OPERAND (t, 0) == temp)
14795 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14796 strict_overflow_p);
14803 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14804 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14806 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14807 get_callee_fndecl (t),
14810 strict_overflow_p);
14812 case COMPOUND_EXPR:
14814 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14815 strict_overflow_p);
14817 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14818 strict_overflow_p);
14820 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14821 strict_overflow_p);
14824 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14828 /* We don't know sign of `t', so be conservative and return false. */
14832 /* Return true if T is known to be non-negative. If the return
14833 value is based on the assumption that signed overflow is undefined,
14834 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14835 *STRICT_OVERFLOW_P. */
14838 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14840 enum tree_code code;
14841 if (t == error_mark_node)
14844 code = TREE_CODE (t);
14845 switch (TREE_CODE_CLASS (code))
14848 case tcc_comparison:
14849 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14851 TREE_OPERAND (t, 0),
14852 TREE_OPERAND (t, 1),
14853 strict_overflow_p);
14856 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14858 TREE_OPERAND (t, 0),
14859 strict_overflow_p);
14862 case tcc_declaration:
14863 case tcc_reference:
14864 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14872 case TRUTH_AND_EXPR:
14873 case TRUTH_OR_EXPR:
14874 case TRUTH_XOR_EXPR:
14875 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14877 TREE_OPERAND (t, 0),
14878 TREE_OPERAND (t, 1),
14879 strict_overflow_p);
14880 case TRUTH_NOT_EXPR:
14881 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14883 TREE_OPERAND (t, 0),
14884 strict_overflow_p);
14891 case WITH_SIZE_EXPR:
14893 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14896 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14900 /* Return true if `t' is known to be non-negative. Handle warnings
14901 about undefined signed overflow. */
14904 tree_expr_nonnegative_p (tree t)
14906 bool ret, strict_overflow_p;
14908 strict_overflow_p = false;
14909 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14910 if (strict_overflow_p)
14911 fold_overflow_warning (("assuming signed overflow does not occur when "
14912 "determining that expression is always "
14914 WARN_STRICT_OVERFLOW_MISC);
14919 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14920 For floating point we further ensure that T is not denormal.
14921 Similar logic is present in nonzero_address in rtlanal.h.
14923 If the return value is based on the assumption that signed overflow
14924 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14925 change *STRICT_OVERFLOW_P. */
14928 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14929 bool *strict_overflow_p)
14934 return tree_expr_nonzero_warnv_p (op0,
14935 strict_overflow_p);
14939 tree inner_type = TREE_TYPE (op0);
14940 tree outer_type = type;
14942 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14943 && tree_expr_nonzero_warnv_p (op0,
14944 strict_overflow_p));
14948 case NON_LVALUE_EXPR:
14949 return tree_expr_nonzero_warnv_p (op0,
14950 strict_overflow_p);
14959 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14960 For floating point we further ensure that T is not denormal.
14961 Similar logic is present in nonzero_address in rtlanal.h.
14963 If the return value is based on the assumption that signed overflow
14964 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14965 change *STRICT_OVERFLOW_P. */
14968 tree_binary_nonzero_warnv_p (enum tree_code code,
14971 tree op1, bool *strict_overflow_p)
14973 bool sub_strict_overflow_p;
14976 case POINTER_PLUS_EXPR:
14978 if (TYPE_OVERFLOW_UNDEFINED (type))
14980 /* With the presence of negative values it is hard
14981 to say something. */
14982 sub_strict_overflow_p = false;
14983 if (!tree_expr_nonnegative_warnv_p (op0,
14984 &sub_strict_overflow_p)
14985 || !tree_expr_nonnegative_warnv_p (op1,
14986 &sub_strict_overflow_p))
14988 /* One of operands must be positive and the other non-negative. */
14989 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14990 overflows, on a twos-complement machine the sum of two
14991 nonnegative numbers can never be zero. */
14992 return (tree_expr_nonzero_warnv_p (op0,
14994 || tree_expr_nonzero_warnv_p (op1,
14995 strict_overflow_p));
15000 if (TYPE_OVERFLOW_UNDEFINED (type))
15002 if (tree_expr_nonzero_warnv_p (op0,
15004 && tree_expr_nonzero_warnv_p (op1,
15005 strict_overflow_p))
15007 *strict_overflow_p = true;
15014 sub_strict_overflow_p = false;
15015 if (tree_expr_nonzero_warnv_p (op0,
15016 &sub_strict_overflow_p)
15017 && tree_expr_nonzero_warnv_p (op1,
15018 &sub_strict_overflow_p))
15020 if (sub_strict_overflow_p)
15021 *strict_overflow_p = true;
15026 sub_strict_overflow_p = false;
15027 if (tree_expr_nonzero_warnv_p (op0,
15028 &sub_strict_overflow_p))
15030 if (sub_strict_overflow_p)
15031 *strict_overflow_p = true;
15033 /* When both operands are nonzero, then MAX must be too. */
15034 if (tree_expr_nonzero_warnv_p (op1,
15035 strict_overflow_p))
15038 /* MAX where operand 0 is positive is positive. */
15039 return tree_expr_nonnegative_warnv_p (op0,
15040 strict_overflow_p);
15042 /* MAX where operand 1 is positive is positive. */
15043 else if (tree_expr_nonzero_warnv_p (op1,
15044 &sub_strict_overflow_p)
15045 && tree_expr_nonnegative_warnv_p (op1,
15046 &sub_strict_overflow_p))
15048 if (sub_strict_overflow_p)
15049 *strict_overflow_p = true;
15055 return (tree_expr_nonzero_warnv_p (op1,
15057 || tree_expr_nonzero_warnv_p (op0,
15058 strict_overflow_p));
15067 /* Return true when T is an address and is known to be nonzero.
15068 For floating point we further ensure that T is not denormal.
15069 Similar logic is present in nonzero_address in rtlanal.h.
15071 If the return value is based on the assumption that signed overflow
15072 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15073 change *STRICT_OVERFLOW_P. */
15076 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15078 bool sub_strict_overflow_p;
15079 switch (TREE_CODE (t))
15082 return !integer_zerop (t);
15086 tree base = TREE_OPERAND (t, 0);
15087 if (!DECL_P (base))
15088 base = get_base_address (base);
15093 /* Weak declarations may link to NULL. Other things may also be NULL
15094 so protect with -fdelete-null-pointer-checks; but not variables
15095 allocated on the stack. */
15097 && (flag_delete_null_pointer_checks
15098 || (DECL_CONTEXT (base)
15099 && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
15100 && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
15101 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15103 /* Constants are never weak. */
15104 if (CONSTANT_CLASS_P (base))
15111 sub_strict_overflow_p = false;
15112 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15113 &sub_strict_overflow_p)
15114 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15115 &sub_strict_overflow_p))
15117 if (sub_strict_overflow_p)
15118 *strict_overflow_p = true;
15129 /* Return true when T is an address and is known to be nonzero.
15130 For floating point we further ensure that T is not denormal.
15131 Similar logic is present in nonzero_address in rtlanal.h.
15133 If the return value is based on the assumption that signed overflow
15134 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15135 change *STRICT_OVERFLOW_P. */
15138 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15140 tree type = TREE_TYPE (t);
15141 enum tree_code code;
15143 /* Doing something useful for floating point would need more work. */
15144 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15147 code = TREE_CODE (t);
15148 switch (TREE_CODE_CLASS (code))
15151 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15152 strict_overflow_p);
15154 case tcc_comparison:
15155 return tree_binary_nonzero_warnv_p (code, type,
15156 TREE_OPERAND (t, 0),
15157 TREE_OPERAND (t, 1),
15158 strict_overflow_p);
15160 case tcc_declaration:
15161 case tcc_reference:
15162 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15170 case TRUTH_NOT_EXPR:
15171 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15172 strict_overflow_p);
15174 case TRUTH_AND_EXPR:
15175 case TRUTH_OR_EXPR:
15176 case TRUTH_XOR_EXPR:
15177 return tree_binary_nonzero_warnv_p (code, type,
15178 TREE_OPERAND (t, 0),
15179 TREE_OPERAND (t, 1),
15180 strict_overflow_p);
15187 case WITH_SIZE_EXPR:
15189 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15191 case COMPOUND_EXPR:
15194 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15195 strict_overflow_p);
15198 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15199 strict_overflow_p);
15202 return alloca_call_p (t);
15210 /* Return true when T is an address and is known to be nonzero.
15211 Handle warnings about undefined signed overflow. */
15214 tree_expr_nonzero_p (tree t)
15216 bool ret, strict_overflow_p;
15218 strict_overflow_p = false;
15219 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15220 if (strict_overflow_p)
15221 fold_overflow_warning (("assuming signed overflow does not occur when "
15222 "determining that expression is always "
15224 WARN_STRICT_OVERFLOW_MISC);
15228 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15229 attempt to fold the expression to a constant without modifying TYPE,
15232 If the expression could be simplified to a constant, then return
15233 the constant. If the expression would not be simplified to a
15234 constant, then return NULL_TREE. */
15237 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15239 tree tem = fold_binary (code, type, op0, op1);
15240 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15243 /* Given the components of a unary expression CODE, TYPE and OP0,
15244 attempt to fold the expression to a constant without modifying
15247 If the expression could be simplified to a constant, then return
15248 the constant. If the expression would not be simplified to a
15249 constant, then return NULL_TREE. */
15252 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15254 tree tem = fold_unary (code, type, op0);
15255 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15258 /* If EXP represents referencing an element in a constant string
15259 (either via pointer arithmetic or array indexing), return the
15260 tree representing the value accessed, otherwise return NULL. */
15263 fold_read_from_constant_string (tree exp)
15265 if ((TREE_CODE (exp) == INDIRECT_REF
15266 || TREE_CODE (exp) == ARRAY_REF)
15267 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15269 tree exp1 = TREE_OPERAND (exp, 0);
15272 location_t loc = EXPR_LOCATION (exp);
15274 if (TREE_CODE (exp) == INDIRECT_REF)
15275 string = string_constant (exp1, &index);
15278 tree low_bound = array_ref_low_bound (exp);
15279 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15281 /* Optimize the special-case of a zero lower bound.
15283 We convert the low_bound to sizetype to avoid some problems
15284 with constant folding. (E.g. suppose the lower bound is 1,
15285 and its mode is QI. Without the conversion,l (ARRAY
15286 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15287 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15288 if (! integer_zerop (low_bound))
15289 index = size_diffop_loc (loc, index,
15290 fold_convert_loc (loc, sizetype, low_bound));
15296 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15297 && TREE_CODE (string) == STRING_CST
15298 && TREE_CODE (index) == INTEGER_CST
15299 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15300 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15302 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15303 return build_int_cst_type (TREE_TYPE (exp),
15304 (TREE_STRING_POINTER (string)
15305 [TREE_INT_CST_LOW (index)]));
15310 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15311 an integer constant, real, or fixed-point constant.
15313 TYPE is the type of the result. */
15316 fold_negate_const (tree arg0, tree type)
15318 tree t = NULL_TREE;
15320 switch (TREE_CODE (arg0))
15324 double_int val = tree_to_double_int (arg0);
15325 int overflow = neg_double (val.low, val.high, &val.low, &val.high);
15327 t = force_fit_type_double (type, val, 1,
15328 (overflow | TREE_OVERFLOW (arg0))
15329 && !TYPE_UNSIGNED (type));
15334 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15339 FIXED_VALUE_TYPE f;
15340 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15341 &(TREE_FIXED_CST (arg0)), NULL,
15342 TYPE_SATURATING (type));
15343 t = build_fixed (type, f);
15344 /* Propagate overflow flags. */
15345 if (overflow_p | TREE_OVERFLOW (arg0))
15346 TREE_OVERFLOW (t) = 1;
15351 gcc_unreachable ();
15357 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15358 an integer constant or real constant.
15360 TYPE is the type of the result. */
15363 fold_abs_const (tree arg0, tree type)
15365 tree t = NULL_TREE;
15367 switch (TREE_CODE (arg0))
15371 double_int val = tree_to_double_int (arg0);
15373 /* If the value is unsigned or non-negative, then the absolute value
15374 is the same as the ordinary value. */
15375 if (TYPE_UNSIGNED (type)
15376 || !double_int_negative_p (val))
15379 /* If the value is negative, then the absolute value is
15385 overflow = neg_double (val.low, val.high, &val.low, &val.high);
15386 t = force_fit_type_double (type, val, -1,
15387 overflow | TREE_OVERFLOW (arg0));
15393 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15394 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15400 gcc_unreachable ();
15406 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15407 constant. TYPE is the type of the result. */
15410 fold_not_const (const_tree arg0, tree type)
15414 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15416 val = double_int_not (tree_to_double_int (arg0));
15417 return force_fit_type_double (type, val, 0, TREE_OVERFLOW (arg0));
15420 /* Given CODE, a relational operator, the target type, TYPE and two
15421 constant operands OP0 and OP1, return the result of the
15422 relational operation. If the result is not a compile time
15423 constant, then return NULL_TREE. */
15426 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15428 int result, invert;
15430 /* From here on, the only cases we handle are when the result is
15431 known to be a constant. */
15433 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15435 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15436 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15438 /* Handle the cases where either operand is a NaN. */
15439 if (real_isnan (c0) || real_isnan (c1))
15449 case UNORDERED_EXPR:
15463 if (flag_trapping_math)
15469 gcc_unreachable ();
15472 return constant_boolean_node (result, type);
15475 return constant_boolean_node (real_compare (code, c0, c1), type);
15478 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15480 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15481 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15482 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15485 /* Handle equality/inequality of complex constants. */
15486 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15488 tree rcond = fold_relational_const (code, type,
15489 TREE_REALPART (op0),
15490 TREE_REALPART (op1));
15491 tree icond = fold_relational_const (code, type,
15492 TREE_IMAGPART (op0),
15493 TREE_IMAGPART (op1));
15494 if (code == EQ_EXPR)
15495 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15496 else if (code == NE_EXPR)
15497 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15502 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15504 To compute GT, swap the arguments and do LT.
15505 To compute GE, do LT and invert the result.
15506 To compute LE, swap the arguments, do LT and invert the result.
15507 To compute NE, do EQ and invert the result.
15509 Therefore, the code below must handle only EQ and LT. */
15511 if (code == LE_EXPR || code == GT_EXPR)
15516 code = swap_tree_comparison (code);
15519 /* Note that it is safe to invert for real values here because we
15520 have already handled the one case that it matters. */
15523 if (code == NE_EXPR || code == GE_EXPR)
15526 code = invert_tree_comparison (code, false);
15529 /* Compute a result for LT or EQ if args permit;
15530 Otherwise return T. */
15531 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15533 if (code == EQ_EXPR)
15534 result = tree_int_cst_equal (op0, op1);
15535 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15536 result = INT_CST_LT_UNSIGNED (op0, op1);
15538 result = INT_CST_LT (op0, op1);
15545 return constant_boolean_node (result, type);
15548 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15549 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15553 fold_build_cleanup_point_expr (tree type, tree expr)
15555 /* If the expression does not have side effects then we don't have to wrap
15556 it with a cleanup point expression. */
15557 if (!TREE_SIDE_EFFECTS (expr))
15560 /* If the expression is a return, check to see if the expression inside the
15561 return has no side effects or the right hand side of the modify expression
15562 inside the return. If either don't have side effects set we don't need to
15563 wrap the expression in a cleanup point expression. Note we don't check the
15564 left hand side of the modify because it should always be a return decl. */
15565 if (TREE_CODE (expr) == RETURN_EXPR)
15567 tree op = TREE_OPERAND (expr, 0);
15568 if (!op || !TREE_SIDE_EFFECTS (op))
15570 op = TREE_OPERAND (op, 1);
15571 if (!TREE_SIDE_EFFECTS (op))
15575 return build1 (CLEANUP_POINT_EXPR, type, expr);
15578 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15579 of an indirection through OP0, or NULL_TREE if no simplification is
15583 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
15589 subtype = TREE_TYPE (sub);
15590 if (!POINTER_TYPE_P (subtype))
15593 if (TREE_CODE (sub) == ADDR_EXPR)
15595 tree op = TREE_OPERAND (sub, 0);
15596 tree optype = TREE_TYPE (op);
15597 /* *&CONST_DECL -> to the value of the const decl. */
15598 if (TREE_CODE (op) == CONST_DECL)
15599 return DECL_INITIAL (op);
15600 /* *&p => p; make sure to handle *&"str"[cst] here. */
15601 if (type == optype)
15603 tree fop = fold_read_from_constant_string (op);
15609 /* *(foo *)&fooarray => fooarray[0] */
15610 else if (TREE_CODE (optype) == ARRAY_TYPE
15611 && type == TREE_TYPE (optype)
15612 && (!in_gimple_form
15613 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
15615 tree type_domain = TYPE_DOMAIN (optype);
15616 tree min_val = size_zero_node;
15617 if (type_domain && TYPE_MIN_VALUE (type_domain))
15618 min_val = TYPE_MIN_VALUE (type_domain);
15620 && TREE_CODE (min_val) != INTEGER_CST)
15622 return build4_loc (loc, ARRAY_REF, type, op, min_val,
15623 NULL_TREE, NULL_TREE);
15625 /* *(foo *)&complexfoo => __real__ complexfoo */
15626 else if (TREE_CODE (optype) == COMPLEX_TYPE
15627 && type == TREE_TYPE (optype))
15628 return fold_build1_loc (loc, REALPART_EXPR, type, op);
15629 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15630 else if (TREE_CODE (optype) == VECTOR_TYPE
15631 && type == TREE_TYPE (optype))
15633 tree part_width = TYPE_SIZE (type);
15634 tree index = bitsize_int (0);
15635 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
15639 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15640 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15642 tree op00 = TREE_OPERAND (sub, 0);
15643 tree op01 = TREE_OPERAND (sub, 1);
15646 if (TREE_CODE (op00) == ADDR_EXPR)
15649 op00 = TREE_OPERAND (op00, 0);
15650 op00type = TREE_TYPE (op00);
15652 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15653 if (TREE_CODE (op00type) == VECTOR_TYPE
15654 && type == TREE_TYPE (op00type))
15656 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15657 tree part_width = TYPE_SIZE (type);
15658 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15659 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15660 tree index = bitsize_int (indexi);
15662 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (op00type))
15663 return fold_build3_loc (loc,
15664 BIT_FIELD_REF, type, op00,
15665 part_width, index);
15668 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15669 else if (TREE_CODE (op00type) == COMPLEX_TYPE
15670 && type == TREE_TYPE (op00type))
15672 tree size = TYPE_SIZE_UNIT (type);
15673 if (tree_int_cst_equal (size, op01))
15674 return fold_build1_loc (loc, IMAGPART_EXPR, type, op00);
15676 /* ((foo *)&fooarray)[1] => fooarray[1] */
15677 else if (TREE_CODE (op00type) == ARRAY_TYPE
15678 && type == TREE_TYPE (op00type))
15680 tree type_domain = TYPE_DOMAIN (op00type);
15681 tree min_val = size_zero_node;
15682 if (type_domain && TYPE_MIN_VALUE (type_domain))
15683 min_val = TYPE_MIN_VALUE (type_domain);
15684 op01 = size_binop_loc (loc, EXACT_DIV_EXPR, op01,
15685 TYPE_SIZE_UNIT (type));
15686 op01 = size_binop_loc (loc, PLUS_EXPR, op01, min_val);
15687 return build4_loc (loc, ARRAY_REF, type, op00, op01,
15688 NULL_TREE, NULL_TREE);
15693 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15694 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15695 && type == TREE_TYPE (TREE_TYPE (subtype))
15696 && (!in_gimple_form
15697 || TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST))
15700 tree min_val = size_zero_node;
15701 sub = build_fold_indirect_ref_loc (loc, sub);
15702 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15703 if (type_domain && TYPE_MIN_VALUE (type_domain))
15704 min_val = TYPE_MIN_VALUE (type_domain);
15706 && TREE_CODE (min_val) != INTEGER_CST)
15708 return build4_loc (loc, ARRAY_REF, type, sub, min_val, NULL_TREE,
15715 /* Builds an expression for an indirection through T, simplifying some
15719 build_fold_indirect_ref_loc (location_t loc, tree t)
15721 tree type = TREE_TYPE (TREE_TYPE (t));
15722 tree sub = fold_indirect_ref_1 (loc, type, t);
15727 return build1_loc (loc, INDIRECT_REF, type, t);
15730 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15733 fold_indirect_ref_loc (location_t loc, tree t)
15735 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
15743 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15744 whose result is ignored. The type of the returned tree need not be
15745 the same as the original expression. */
15748 fold_ignored_result (tree t)
15750 if (!TREE_SIDE_EFFECTS (t))
15751 return integer_zero_node;
15754 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15757 t = TREE_OPERAND (t, 0);
15761 case tcc_comparison:
15762 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15763 t = TREE_OPERAND (t, 0);
15764 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15765 t = TREE_OPERAND (t, 1);
15770 case tcc_expression:
15771 switch (TREE_CODE (t))
15773 case COMPOUND_EXPR:
15774 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15776 t = TREE_OPERAND (t, 0);
15780 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15781 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15783 t = TREE_OPERAND (t, 0);
15796 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15797 This can only be applied to objects of a sizetype. */
15800 round_up_loc (location_t loc, tree value, int divisor)
15802 tree div = NULL_TREE;
15804 gcc_assert (divisor > 0);
15808 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15809 have to do anything. Only do this when we are not given a const,
15810 because in that case, this check is more expensive than just
15812 if (TREE_CODE (value) != INTEGER_CST)
15814 div = build_int_cst (TREE_TYPE (value), divisor);
15816 if (multiple_of_p (TREE_TYPE (value), value, div))
15820 /* If divisor is a power of two, simplify this to bit manipulation. */
15821 if (divisor == (divisor & -divisor))
15823 if (TREE_CODE (value) == INTEGER_CST)
15825 double_int val = tree_to_double_int (value);
15828 if ((val.low & (divisor - 1)) == 0)
15831 overflow_p = TREE_OVERFLOW (value);
15832 val.low &= ~(divisor - 1);
15833 val.low += divisor;
15841 return force_fit_type_double (TREE_TYPE (value), val,
15848 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15849 value = size_binop_loc (loc, PLUS_EXPR, value, t);
15850 t = build_int_cst (TREE_TYPE (value), -divisor);
15851 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15857 div = build_int_cst (TREE_TYPE (value), divisor);
15858 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
15859 value = size_binop_loc (loc, MULT_EXPR, value, div);
15865 /* Likewise, but round down. */
15868 round_down_loc (location_t loc, tree value, int divisor)
15870 tree div = NULL_TREE;
15872 gcc_assert (divisor > 0);
15876 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15877 have to do anything. Only do this when we are not given a const,
15878 because in that case, this check is more expensive than just
15880 if (TREE_CODE (value) != INTEGER_CST)
15882 div = build_int_cst (TREE_TYPE (value), divisor);
15884 if (multiple_of_p (TREE_TYPE (value), value, div))
15888 /* If divisor is a power of two, simplify this to bit manipulation. */
15889 if (divisor == (divisor & -divisor))
15893 t = build_int_cst (TREE_TYPE (value), -divisor);
15894 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15899 div = build_int_cst (TREE_TYPE (value), divisor);
15900 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
15901 value = size_binop_loc (loc, MULT_EXPR, value, div);
15907 /* Returns the pointer to the base of the object addressed by EXP and
15908 extracts the information about the offset of the access, storing it
15909 to PBITPOS and POFFSET. */
15912 split_address_to_core_and_offset (tree exp,
15913 HOST_WIDE_INT *pbitpos, tree *poffset)
15916 enum machine_mode mode;
15917 int unsignedp, volatilep;
15918 HOST_WIDE_INT bitsize;
15919 location_t loc = EXPR_LOCATION (exp);
15921 if (TREE_CODE (exp) == ADDR_EXPR)
15923 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15924 poffset, &mode, &unsignedp, &volatilep,
15926 core = build_fold_addr_expr_loc (loc, core);
15932 *poffset = NULL_TREE;
15938 /* Returns true if addresses of E1 and E2 differ by a constant, false
15939 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15942 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15945 HOST_WIDE_INT bitpos1, bitpos2;
15946 tree toffset1, toffset2, tdiff, type;
15948 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15949 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15951 if (bitpos1 % BITS_PER_UNIT != 0
15952 || bitpos2 % BITS_PER_UNIT != 0
15953 || !operand_equal_p (core1, core2, 0))
15956 if (toffset1 && toffset2)
15958 type = TREE_TYPE (toffset1);
15959 if (type != TREE_TYPE (toffset2))
15960 toffset2 = fold_convert (type, toffset2);
15962 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15963 if (!cst_and_fits_in_hwi (tdiff))
15966 *diff = int_cst_value (tdiff);
15968 else if (toffset1 || toffset2)
15970 /* If only one of the offsets is non-constant, the difference cannot
15977 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15981 /* Simplify the floating point expression EXP when the sign of the
15982 result is not significant. Return NULL_TREE if no simplification
15986 fold_strip_sign_ops (tree exp)
15989 location_t loc = EXPR_LOCATION (exp);
15991 switch (TREE_CODE (exp))
15995 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15996 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
16000 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
16002 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16003 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16004 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
16005 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
16006 arg0 ? arg0 : TREE_OPERAND (exp, 0),
16007 arg1 ? arg1 : TREE_OPERAND (exp, 1));
16010 case COMPOUND_EXPR:
16011 arg0 = TREE_OPERAND (exp, 0);
16012 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16014 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
16018 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16019 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
16021 return fold_build3_loc (loc,
16022 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
16023 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16024 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16029 const enum built_in_function fcode = builtin_mathfn_code (exp);
16032 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16033 /* Strip copysign function call, return the 1st argument. */
16034 arg0 = CALL_EXPR_ARG (exp, 0);
16035 arg1 = CALL_EXPR_ARG (exp, 1);
16036 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16039 /* Strip sign ops from the argument of "odd" math functions. */
16040 if (negate_mathfn_p (fcode))
16042 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16044 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);