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
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"
61 #include "langhooks.h"
64 #include "tree-flow.h"
66 /* Nonzero if we are folding constants inside an initializer; zero
68 int folding_initializer = 0;
70 /* The following constants represent a bit based encoding of GCC's
71 comparison operators. This encoding simplifies transformations
72 on relational comparison operators, such as AND and OR. */
73 enum comparison_code {
92 static bool negate_mathfn_p (enum built_in_function);
93 static bool negate_expr_p (tree);
94 static tree negate_expr (tree);
95 static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int);
96 static tree associate_trees (location_t, tree, tree, enum tree_code, tree);
97 static tree const_binop (enum tree_code, tree, tree);
98 static enum comparison_code comparison_to_compcode (enum tree_code);
99 static enum tree_code compcode_to_comparison (enum comparison_code);
100 static int operand_equal_for_comparison_p (tree, tree, tree);
101 static int twoval_comparison_p (tree, tree *, tree *, int *);
102 static tree eval_subst (location_t, tree, tree, tree, tree, tree);
103 static tree pedantic_omit_one_operand_loc (location_t, tree, tree, tree);
104 static tree distribute_bit_expr (location_t, enum tree_code, tree, tree, tree);
105 static tree make_bit_field_ref (location_t, tree, tree,
106 HOST_WIDE_INT, HOST_WIDE_INT, int);
107 static tree optimize_bit_field_compare (location_t, enum tree_code,
109 static tree decode_field_reference (location_t, tree, HOST_WIDE_INT *,
111 enum machine_mode *, int *, int *,
113 static int all_ones_mask_p (const_tree, int);
114 static tree sign_bit_p (tree, const_tree);
115 static int simple_operand_p (const_tree);
116 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
117 static tree range_predecessor (tree);
118 static tree range_successor (tree);
119 extern tree make_range (tree, int *, tree *, tree *, bool *);
120 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
122 static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
123 static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
124 static tree unextend (tree, int, int, tree);
125 static tree fold_truthop (location_t, enum tree_code, tree, tree, tree);
126 static tree optimize_minmax_comparison (location_t, enum tree_code,
128 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
129 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
130 static tree fold_binary_op_with_conditional_arg (location_t,
131 enum tree_code, tree,
134 static tree fold_mathfn_compare (location_t,
135 enum built_in_function, enum tree_code,
137 static tree fold_inf_compare (location_t, enum tree_code, tree, tree, tree);
138 static tree fold_div_compare (location_t, enum tree_code, tree, tree, tree);
139 static bool reorder_operands_p (const_tree, const_tree);
140 static tree fold_negate_const (tree, tree);
141 static tree fold_not_const (const_tree, tree);
142 static tree fold_relational_const (enum tree_code, tree, tree, tree);
143 static tree fold_convert_const (enum tree_code, tree, tree);
146 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
147 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
148 and SUM1. Then this yields nonzero if overflow occurred during the
151 Overflow occurs if A and B have the same sign, but A and SUM differ in
152 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
154 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
156 /* If ARG2 divides ARG1 with zero remainder, carries out the division
157 of type CODE and returns the quotient.
158 Otherwise returns NULL_TREE. */
161 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
166 /* The sign of the division is according to operand two, that
167 does the correct thing for POINTER_PLUS_EXPR where we want
168 a signed division. */
169 uns = TYPE_UNSIGNED (TREE_TYPE (arg2));
170 if (TREE_CODE (TREE_TYPE (arg2)) == INTEGER_TYPE
171 && TYPE_IS_SIZETYPE (TREE_TYPE (arg2)))
174 quo = double_int_divmod (tree_to_double_int (arg1),
175 tree_to_double_int (arg2),
178 if (double_int_zero_p (rem))
179 return build_int_cst_wide (TREE_TYPE (arg1), quo.low, quo.high);
184 /* This is nonzero if we should defer warnings about undefined
185 overflow. This facility exists because these warnings are a
186 special case. The code to estimate loop iterations does not want
187 to issue any warnings, since it works with expressions which do not
188 occur in user code. Various bits of cleanup code call fold(), but
189 only use the result if it has certain characteristics (e.g., is a
190 constant); that code only wants to issue a warning if the result is
193 static int fold_deferring_overflow_warnings;
195 /* If a warning about undefined overflow is deferred, this is the
196 warning. Note that this may cause us to turn two warnings into
197 one, but that is fine since it is sufficient to only give one
198 warning per expression. */
200 static const char* fold_deferred_overflow_warning;
202 /* If a warning about undefined overflow is deferred, this is the
203 level at which the warning should be emitted. */
205 static enum warn_strict_overflow_code fold_deferred_overflow_code;
207 /* Start deferring overflow warnings. We could use a stack here to
208 permit nested calls, but at present it is not necessary. */
211 fold_defer_overflow_warnings (void)
213 ++fold_deferring_overflow_warnings;
216 /* Stop deferring overflow warnings. If there is a pending warning,
217 and ISSUE is true, then issue the warning if appropriate. STMT is
218 the statement with which the warning should be associated (used for
219 location information); STMT may be NULL. CODE is the level of the
220 warning--a warn_strict_overflow_code value. This function will use
221 the smaller of CODE and the deferred code when deciding whether to
222 issue the warning. CODE may be zero to mean to always use the
226 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
231 gcc_assert (fold_deferring_overflow_warnings > 0);
232 --fold_deferring_overflow_warnings;
233 if (fold_deferring_overflow_warnings > 0)
235 if (fold_deferred_overflow_warning != NULL
237 && code < (int) fold_deferred_overflow_code)
238 fold_deferred_overflow_code = (enum warn_strict_overflow_code) code;
242 warnmsg = fold_deferred_overflow_warning;
243 fold_deferred_overflow_warning = NULL;
245 if (!issue || warnmsg == NULL)
248 if (gimple_no_warning_p (stmt))
251 /* Use the smallest code level when deciding to issue the
253 if (code == 0 || code > (int) fold_deferred_overflow_code)
254 code = fold_deferred_overflow_code;
256 if (!issue_strict_overflow_warning (code))
260 locus = input_location;
262 locus = gimple_location (stmt);
263 warning_at (locus, OPT_Wstrict_overflow, "%s", warnmsg);
266 /* Stop deferring overflow warnings, ignoring any deferred
270 fold_undefer_and_ignore_overflow_warnings (void)
272 fold_undefer_overflow_warnings (false, NULL, 0);
275 /* Whether we are deferring overflow warnings. */
278 fold_deferring_overflow_warnings_p (void)
280 return fold_deferring_overflow_warnings > 0;
283 /* This is called when we fold something based on the fact that signed
284 overflow is undefined. */
287 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
289 if (fold_deferring_overflow_warnings > 0)
291 if (fold_deferred_overflow_warning == NULL
292 || wc < fold_deferred_overflow_code)
294 fold_deferred_overflow_warning = gmsgid;
295 fold_deferred_overflow_code = wc;
298 else if (issue_strict_overflow_warning (wc))
299 warning (OPT_Wstrict_overflow, gmsgid);
302 /* Return true if the built-in mathematical function specified by CODE
303 is odd, i.e. -f(x) == f(-x). */
306 negate_mathfn_p (enum built_in_function code)
310 CASE_FLT_FN (BUILT_IN_ASIN):
311 CASE_FLT_FN (BUILT_IN_ASINH):
312 CASE_FLT_FN (BUILT_IN_ATAN):
313 CASE_FLT_FN (BUILT_IN_ATANH):
314 CASE_FLT_FN (BUILT_IN_CASIN):
315 CASE_FLT_FN (BUILT_IN_CASINH):
316 CASE_FLT_FN (BUILT_IN_CATAN):
317 CASE_FLT_FN (BUILT_IN_CATANH):
318 CASE_FLT_FN (BUILT_IN_CBRT):
319 CASE_FLT_FN (BUILT_IN_CPROJ):
320 CASE_FLT_FN (BUILT_IN_CSIN):
321 CASE_FLT_FN (BUILT_IN_CSINH):
322 CASE_FLT_FN (BUILT_IN_CTAN):
323 CASE_FLT_FN (BUILT_IN_CTANH):
324 CASE_FLT_FN (BUILT_IN_ERF):
325 CASE_FLT_FN (BUILT_IN_LLROUND):
326 CASE_FLT_FN (BUILT_IN_LROUND):
327 CASE_FLT_FN (BUILT_IN_ROUND):
328 CASE_FLT_FN (BUILT_IN_SIN):
329 CASE_FLT_FN (BUILT_IN_SINH):
330 CASE_FLT_FN (BUILT_IN_TAN):
331 CASE_FLT_FN (BUILT_IN_TANH):
332 CASE_FLT_FN (BUILT_IN_TRUNC):
335 CASE_FLT_FN (BUILT_IN_LLRINT):
336 CASE_FLT_FN (BUILT_IN_LRINT):
337 CASE_FLT_FN (BUILT_IN_NEARBYINT):
338 CASE_FLT_FN (BUILT_IN_RINT):
339 return !flag_rounding_math;
347 /* Check whether we may negate an integer constant T without causing
351 may_negate_without_overflow_p (const_tree t)
353 unsigned HOST_WIDE_INT val;
357 gcc_assert (TREE_CODE (t) == INTEGER_CST);
359 type = TREE_TYPE (t);
360 if (TYPE_UNSIGNED (type))
363 prec = TYPE_PRECISION (type);
364 if (prec > HOST_BITS_PER_WIDE_INT)
366 if (TREE_INT_CST_LOW (t) != 0)
368 prec -= HOST_BITS_PER_WIDE_INT;
369 val = TREE_INT_CST_HIGH (t);
372 val = TREE_INT_CST_LOW (t);
373 if (prec < HOST_BITS_PER_WIDE_INT)
374 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
375 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
378 /* Determine whether an expression T can be cheaply negated using
379 the function negate_expr without introducing undefined overflow. */
382 negate_expr_p (tree t)
389 type = TREE_TYPE (t);
392 switch (TREE_CODE (t))
395 if (TYPE_OVERFLOW_WRAPS (type))
398 /* Check that -CST will not overflow type. */
399 return may_negate_without_overflow_p (t);
401 return (INTEGRAL_TYPE_P (type)
402 && TYPE_OVERFLOW_WRAPS (type));
409 /* We want to canonicalize to positive real constants. Pretend
410 that only negative ones can be easily negated. */
411 return REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
414 return negate_expr_p (TREE_REALPART (t))
415 && negate_expr_p (TREE_IMAGPART (t));
418 return negate_expr_p (TREE_OPERAND (t, 0))
419 && negate_expr_p (TREE_OPERAND (t, 1));
422 return negate_expr_p (TREE_OPERAND (t, 0));
425 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
426 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
428 /* -(A + B) -> (-B) - A. */
429 if (negate_expr_p (TREE_OPERAND (t, 1))
430 && reorder_operands_p (TREE_OPERAND (t, 0),
431 TREE_OPERAND (t, 1)))
433 /* -(A + B) -> (-A) - B. */
434 return negate_expr_p (TREE_OPERAND (t, 0));
437 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
438 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
439 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
440 && reorder_operands_p (TREE_OPERAND (t, 0),
441 TREE_OPERAND (t, 1));
444 if (TYPE_UNSIGNED (TREE_TYPE (t)))
450 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
451 return negate_expr_p (TREE_OPERAND (t, 1))
452 || negate_expr_p (TREE_OPERAND (t, 0));
460 /* In general we can't negate A / B, because if A is INT_MIN and
461 B is 1, we may turn this into INT_MIN / -1 which is undefined
462 and actually traps on some architectures. But if overflow is
463 undefined, we can negate, because - (INT_MIN / 1) is an
465 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
466 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
468 return negate_expr_p (TREE_OPERAND (t, 1))
469 || negate_expr_p (TREE_OPERAND (t, 0));
472 /* Negate -((double)float) as (double)(-float). */
473 if (TREE_CODE (type) == REAL_TYPE)
475 tree tem = strip_float_extensions (t);
477 return negate_expr_p (tem);
482 /* Negate -f(x) as f(-x). */
483 if (negate_mathfn_p (builtin_mathfn_code (t)))
484 return negate_expr_p (CALL_EXPR_ARG (t, 0));
488 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
489 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
491 tree op1 = TREE_OPERAND (t, 1);
492 if (TREE_INT_CST_HIGH (op1) == 0
493 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
494 == TREE_INT_CST_LOW (op1))
505 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
506 simplification is possible.
507 If negate_expr_p would return true for T, NULL_TREE will never be
511 fold_negate_expr (location_t loc, tree t)
513 tree type = TREE_TYPE (t);
516 switch (TREE_CODE (t))
518 /* Convert - (~A) to A + 1. */
520 if (INTEGRAL_TYPE_P (type))
521 return fold_build2_loc (loc, PLUS_EXPR, type, TREE_OPERAND (t, 0),
522 build_int_cst (type, 1));
526 tem = fold_negate_const (t, type);
527 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
528 || !TYPE_OVERFLOW_TRAPS (type))
533 tem = fold_negate_const (t, type);
534 /* Two's complement FP formats, such as c4x, may overflow. */
535 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
540 tem = fold_negate_const (t, type);
545 tree rpart = negate_expr (TREE_REALPART (t));
546 tree ipart = negate_expr (TREE_IMAGPART (t));
548 if ((TREE_CODE (rpart) == REAL_CST
549 && TREE_CODE (ipart) == REAL_CST)
550 || (TREE_CODE (rpart) == INTEGER_CST
551 && TREE_CODE (ipart) == INTEGER_CST))
552 return build_complex (type, rpart, ipart);
557 if (negate_expr_p (t))
558 return fold_build2_loc (loc, COMPLEX_EXPR, type,
559 fold_negate_expr (loc, TREE_OPERAND (t, 0)),
560 fold_negate_expr (loc, TREE_OPERAND (t, 1)));
564 if (negate_expr_p (t))
565 return fold_build1_loc (loc, CONJ_EXPR, type,
566 fold_negate_expr (loc, TREE_OPERAND (t, 0)));
570 return TREE_OPERAND (t, 0);
573 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
574 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
576 /* -(A + B) -> (-B) - A. */
577 if (negate_expr_p (TREE_OPERAND (t, 1))
578 && reorder_operands_p (TREE_OPERAND (t, 0),
579 TREE_OPERAND (t, 1)))
581 tem = negate_expr (TREE_OPERAND (t, 1));
582 return fold_build2_loc (loc, MINUS_EXPR, type,
583 tem, TREE_OPERAND (t, 0));
586 /* -(A + B) -> (-A) - B. */
587 if (negate_expr_p (TREE_OPERAND (t, 0)))
589 tem = negate_expr (TREE_OPERAND (t, 0));
590 return fold_build2_loc (loc, MINUS_EXPR, type,
591 tem, TREE_OPERAND (t, 1));
597 /* - (A - B) -> B - A */
598 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
599 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
600 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
601 return fold_build2_loc (loc, MINUS_EXPR, type,
602 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
606 if (TYPE_UNSIGNED (type))
612 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
614 tem = TREE_OPERAND (t, 1);
615 if (negate_expr_p (tem))
616 return fold_build2_loc (loc, TREE_CODE (t), type,
617 TREE_OPERAND (t, 0), negate_expr (tem));
618 tem = TREE_OPERAND (t, 0);
619 if (negate_expr_p (tem))
620 return fold_build2_loc (loc, TREE_CODE (t), type,
621 negate_expr (tem), TREE_OPERAND (t, 1));
630 /* In general we can't negate A / B, because if A is INT_MIN and
631 B is 1, we may turn this into INT_MIN / -1 which is undefined
632 and actually traps on some architectures. But if overflow is
633 undefined, we can negate, because - (INT_MIN / 1) is an
635 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
637 const char * const warnmsg = G_("assuming signed overflow does not "
638 "occur when negating a division");
639 tem = TREE_OPERAND (t, 1);
640 if (negate_expr_p (tem))
642 if (INTEGRAL_TYPE_P (type)
643 && (TREE_CODE (tem) != INTEGER_CST
644 || integer_onep (tem)))
645 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
646 return fold_build2_loc (loc, TREE_CODE (t), type,
647 TREE_OPERAND (t, 0), negate_expr (tem));
649 tem = TREE_OPERAND (t, 0);
650 if (negate_expr_p (tem))
652 if (INTEGRAL_TYPE_P (type)
653 && (TREE_CODE (tem) != INTEGER_CST
654 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
655 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
656 return fold_build2_loc (loc, TREE_CODE (t), type,
657 negate_expr (tem), TREE_OPERAND (t, 1));
663 /* Convert -((double)float) into (double)(-float). */
664 if (TREE_CODE (type) == REAL_TYPE)
666 tem = strip_float_extensions (t);
667 if (tem != t && negate_expr_p (tem))
668 return fold_convert_loc (loc, type, negate_expr (tem));
673 /* Negate -f(x) as f(-x). */
674 if (negate_mathfn_p (builtin_mathfn_code (t))
675 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
679 fndecl = get_callee_fndecl (t);
680 arg = negate_expr (CALL_EXPR_ARG (t, 0));
681 return build_call_expr_loc (loc, fndecl, 1, arg);
686 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
687 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
689 tree op1 = TREE_OPERAND (t, 1);
690 if (TREE_INT_CST_HIGH (op1) == 0
691 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
692 == TREE_INT_CST_LOW (op1))
694 tree ntype = TYPE_UNSIGNED (type)
695 ? signed_type_for (type)
696 : unsigned_type_for (type);
697 tree temp = fold_convert_loc (loc, ntype, TREE_OPERAND (t, 0));
698 temp = fold_build2_loc (loc, RSHIFT_EXPR, ntype, temp, op1);
699 return fold_convert_loc (loc, type, temp);
711 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
712 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
724 loc = EXPR_LOCATION (t);
725 type = TREE_TYPE (t);
728 tem = fold_negate_expr (loc, t);
731 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
732 SET_EXPR_LOCATION (tem, loc);
734 return fold_convert_loc (loc, type, tem);
737 /* Split a tree IN into a constant, literal and variable parts that could be
738 combined with CODE to make IN. "constant" means an expression with
739 TREE_CONSTANT but that isn't an actual constant. CODE must be a
740 commutative arithmetic operation. Store the constant part into *CONP,
741 the literal in *LITP and return the variable part. If a part isn't
742 present, set it to null. If the tree does not decompose in this way,
743 return the entire tree as the variable part and the other parts as null.
745 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
746 case, we negate an operand that was subtracted. Except if it is a
747 literal for which we use *MINUS_LITP instead.
749 If NEGATE_P is true, we are negating all of IN, again except a literal
750 for which we use *MINUS_LITP instead.
752 If IN is itself a literal or constant, return it as appropriate.
754 Note that we do not guarantee that any of the three values will be the
755 same type as IN, but they will have the same signedness and mode. */
758 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
759 tree *minus_litp, int negate_p)
767 /* Strip any conversions that don't change the machine mode or signedness. */
768 STRIP_SIGN_NOPS (in);
770 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
771 || TREE_CODE (in) == FIXED_CST)
773 else if (TREE_CODE (in) == code
774 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
775 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
776 /* We can associate addition and subtraction together (even
777 though the C standard doesn't say so) for integers because
778 the value is not affected. For reals, the value might be
779 affected, so we can't. */
780 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
781 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
783 tree op0 = TREE_OPERAND (in, 0);
784 tree op1 = TREE_OPERAND (in, 1);
785 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
786 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
788 /* First see if either of the operands is a literal, then a constant. */
789 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
790 || TREE_CODE (op0) == FIXED_CST)
791 *litp = op0, op0 = 0;
792 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
793 || TREE_CODE (op1) == FIXED_CST)
794 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
796 if (op0 != 0 && TREE_CONSTANT (op0))
797 *conp = op0, op0 = 0;
798 else if (op1 != 0 && TREE_CONSTANT (op1))
799 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
801 /* If we haven't dealt with either operand, this is not a case we can
802 decompose. Otherwise, VAR is either of the ones remaining, if any. */
803 if (op0 != 0 && op1 != 0)
808 var = op1, neg_var_p = neg1_p;
810 /* Now do any needed negations. */
812 *minus_litp = *litp, *litp = 0;
814 *conp = negate_expr (*conp);
816 var = negate_expr (var);
818 else if (TREE_CONSTANT (in))
826 *minus_litp = *litp, *litp = 0;
827 else if (*minus_litp)
828 *litp = *minus_litp, *minus_litp = 0;
829 *conp = negate_expr (*conp);
830 var = negate_expr (var);
836 /* Re-associate trees split by the above function. T1 and T2 are
837 either expressions to associate or null. Return the new
838 expression, if any. LOC is the location of the new expression. If
839 we build an operation, do it in TYPE and with CODE. */
842 associate_trees (location_t loc, tree t1, tree t2, enum tree_code code, tree type)
851 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
852 try to fold this since we will have infinite recursion. But do
853 deal with any NEGATE_EXPRs. */
854 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
855 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
857 if (code == PLUS_EXPR)
859 if (TREE_CODE (t1) == NEGATE_EXPR)
860 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t2),
861 fold_convert_loc (loc, type, TREE_OPERAND (t1, 0)));
862 else if (TREE_CODE (t2) == NEGATE_EXPR)
863 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t1),
864 fold_convert_loc (loc, type, TREE_OPERAND (t2, 0)));
865 else if (integer_zerop (t2))
866 return fold_convert_loc (loc, type, t1);
868 else if (code == MINUS_EXPR)
870 if (integer_zerop (t2))
871 return fold_convert_loc (loc, type, t1);
874 tem = build2 (code, type, fold_convert_loc (loc, type, t1),
875 fold_convert_loc (loc, type, t2));
876 goto associate_trees_exit;
879 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
880 fold_convert_loc (loc, type, t2));
881 associate_trees_exit:
882 protected_set_expr_location (tem, loc);
886 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
887 for use in int_const_binop, size_binop and size_diffop. */
890 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
892 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
894 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
909 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
910 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
911 && TYPE_MODE (type1) == TYPE_MODE (type2);
915 /* Combine two integer constants ARG1 and ARG2 under operation CODE
916 to produce a new constant. Return NULL_TREE if we don't know how
917 to evaluate CODE at compile-time.
919 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
922 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
924 double_int op1, op2, res, tmp;
926 tree type = TREE_TYPE (arg1);
927 bool uns = TYPE_UNSIGNED (type);
929 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
930 bool overflow = false;
932 op1 = tree_to_double_int (arg1);
933 op2 = tree_to_double_int (arg2);
938 res = double_int_ior (op1, op2);
942 res = double_int_xor (op1, op2);
946 res = double_int_and (op1, op2);
950 res = double_int_rshift (op1, double_int_to_shwi (op2),
951 TYPE_PRECISION (type), !uns);
955 /* It's unclear from the C standard whether shifts can overflow.
956 The following code ignores overflow; perhaps a C standard
957 interpretation ruling is needed. */
958 res = double_int_lshift (op1, double_int_to_shwi (op2),
959 TYPE_PRECISION (type), !uns);
963 res = double_int_rrotate (op1, double_int_to_shwi (op2),
964 TYPE_PRECISION (type));
968 res = double_int_lrotate (op1, double_int_to_shwi (op2),
969 TYPE_PRECISION (type));
973 overflow = add_double (op1.low, op1.high, op2.low, op2.high,
974 &res.low, &res.high);
978 neg_double (op2.low, op2.high, &res.low, &res.high);
979 add_double (op1.low, op1.high, res.low, res.high,
980 &res.low, &res.high);
981 overflow = OVERFLOW_SUM_SIGN (res.high, op2.high, op1.high);
985 overflow = mul_double (op1.low, op1.high, op2.low, op2.high,
986 &res.low, &res.high);
990 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
992 /* This is a shortcut for a common special case. */
993 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
994 && !TREE_OVERFLOW (arg1)
995 && !TREE_OVERFLOW (arg2)
996 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
998 if (code == CEIL_DIV_EXPR)
999 op1.low += op2.low - 1;
1001 res.low = op1.low / op2.low, res.high = 0;
1005 /* ... fall through ... */
1007 case ROUND_DIV_EXPR:
1008 if (double_int_zero_p (op2))
1010 if (double_int_one_p (op2))
1015 if (double_int_equal_p (op1, op2)
1016 && ! double_int_zero_p (op1))
1018 res = double_int_one;
1021 overflow = div_and_round_double (code, uns,
1022 op1.low, op1.high, op2.low, op2.high,
1023 &res.low, &res.high,
1024 &tmp.low, &tmp.high);
1027 case TRUNC_MOD_EXPR:
1028 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1029 /* This is a shortcut for a common special case. */
1030 if (op2.high == 0 && (HOST_WIDE_INT) op2.low > 0
1031 && !TREE_OVERFLOW (arg1)
1032 && !TREE_OVERFLOW (arg2)
1033 && op1.high == 0 && (HOST_WIDE_INT) op1.low >= 0)
1035 if (code == CEIL_MOD_EXPR)
1036 op1.low += op2.low - 1;
1037 res.low = op1.low % op2.low, res.high = 0;
1041 /* ... fall through ... */
1043 case ROUND_MOD_EXPR:
1044 if (double_int_zero_p (op2))
1046 overflow = div_and_round_double (code, uns,
1047 op1.low, op1.high, op2.low, op2.high,
1048 &tmp.low, &tmp.high,
1049 &res.low, &res.high);
1053 res = double_int_min (op1, op2, uns);
1057 res = double_int_max (op1, op2, uns);
1066 t = build_int_cst_wide (TREE_TYPE (arg1), res.low, res.high);
1068 /* Propagate overflow flags ourselves. */
1069 if (((!uns || is_sizetype) && overflow)
1070 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1073 TREE_OVERFLOW (t) = 1;
1077 t = force_fit_type_double (TREE_TYPE (arg1), res, 1,
1078 ((!uns || is_sizetype) && overflow)
1079 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1084 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1085 constant. We assume ARG1 and ARG2 have the same data type, or at least
1086 are the same kind of constant and the same machine mode. Return zero if
1087 combining the constants is not allowed in the current operating mode. */
1090 const_binop (enum tree_code code, tree arg1, tree arg2)
1092 /* Sanity check for the recursive cases. */
1099 if (TREE_CODE (arg1) == INTEGER_CST)
1100 return int_const_binop (code, arg1, arg2, 0);
1102 if (TREE_CODE (arg1) == REAL_CST)
1104 enum machine_mode mode;
1107 REAL_VALUE_TYPE value;
1108 REAL_VALUE_TYPE result;
1112 /* The following codes are handled by real_arithmetic. */
1127 d1 = TREE_REAL_CST (arg1);
1128 d2 = TREE_REAL_CST (arg2);
1130 type = TREE_TYPE (arg1);
1131 mode = TYPE_MODE (type);
1133 /* Don't perform operation if we honor signaling NaNs and
1134 either operand is a NaN. */
1135 if (HONOR_SNANS (mode)
1136 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1139 /* Don't perform operation if it would raise a division
1140 by zero exception. */
1141 if (code == RDIV_EXPR
1142 && REAL_VALUES_EQUAL (d2, dconst0)
1143 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1146 /* If either operand is a NaN, just return it. Otherwise, set up
1147 for floating-point trap; we return an overflow. */
1148 if (REAL_VALUE_ISNAN (d1))
1150 else if (REAL_VALUE_ISNAN (d2))
1153 inexact = real_arithmetic (&value, code, &d1, &d2);
1154 real_convert (&result, mode, &value);
1156 /* Don't constant fold this floating point operation if
1157 the result has overflowed and flag_trapping_math. */
1158 if (flag_trapping_math
1159 && MODE_HAS_INFINITIES (mode)
1160 && REAL_VALUE_ISINF (result)
1161 && !REAL_VALUE_ISINF (d1)
1162 && !REAL_VALUE_ISINF (d2))
1165 /* Don't constant fold this floating point operation if the
1166 result may dependent upon the run-time rounding mode and
1167 flag_rounding_math is set, or if GCC's software emulation
1168 is unable to accurately represent the result. */
1169 if ((flag_rounding_math
1170 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1171 && (inexact || !real_identical (&result, &value)))
1174 t = build_real (type, result);
1176 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1180 if (TREE_CODE (arg1) == FIXED_CST)
1182 FIXED_VALUE_TYPE f1;
1183 FIXED_VALUE_TYPE f2;
1184 FIXED_VALUE_TYPE result;
1189 /* The following codes are handled by fixed_arithmetic. */
1195 case TRUNC_DIV_EXPR:
1196 f2 = TREE_FIXED_CST (arg2);
1201 f2.data.high = TREE_INT_CST_HIGH (arg2);
1202 f2.data.low = TREE_INT_CST_LOW (arg2);
1210 f1 = TREE_FIXED_CST (arg1);
1211 type = TREE_TYPE (arg1);
1212 sat_p = TYPE_SATURATING (type);
1213 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1214 t = build_fixed (type, result);
1215 /* Propagate overflow flags. */
1216 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1217 TREE_OVERFLOW (t) = 1;
1221 if (TREE_CODE (arg1) == COMPLEX_CST)
1223 tree type = TREE_TYPE (arg1);
1224 tree r1 = TREE_REALPART (arg1);
1225 tree i1 = TREE_IMAGPART (arg1);
1226 tree r2 = TREE_REALPART (arg2);
1227 tree i2 = TREE_IMAGPART (arg2);
1234 real = const_binop (code, r1, r2);
1235 imag = const_binop (code, i1, i2);
1239 if (COMPLEX_FLOAT_TYPE_P (type))
1240 return do_mpc_arg2 (arg1, arg2, type,
1241 /* do_nonfinite= */ folding_initializer,
1244 real = const_binop (MINUS_EXPR,
1245 const_binop (MULT_EXPR, r1, r2),
1246 const_binop (MULT_EXPR, i1, i2));
1247 imag = const_binop (PLUS_EXPR,
1248 const_binop (MULT_EXPR, r1, i2),
1249 const_binop (MULT_EXPR, i1, r2));
1253 if (COMPLEX_FLOAT_TYPE_P (type))
1254 return do_mpc_arg2 (arg1, arg2, type,
1255 /* do_nonfinite= */ folding_initializer,
1258 case TRUNC_DIV_EXPR:
1260 case FLOOR_DIV_EXPR:
1261 case ROUND_DIV_EXPR:
1262 if (flag_complex_method == 0)
1264 /* Keep this algorithm in sync with
1265 tree-complex.c:expand_complex_div_straight().
1267 Expand complex division to scalars, straightforward algorithm.
1268 a / b = ((ar*br + ai*bi)/t) + i((ai*br - ar*bi)/t)
1272 = const_binop (PLUS_EXPR,
1273 const_binop (MULT_EXPR, r2, r2),
1274 const_binop (MULT_EXPR, i2, i2));
1276 = const_binop (PLUS_EXPR,
1277 const_binop (MULT_EXPR, r1, r2),
1278 const_binop (MULT_EXPR, i1, i2));
1280 = const_binop (MINUS_EXPR,
1281 const_binop (MULT_EXPR, i1, r2),
1282 const_binop (MULT_EXPR, r1, i2));
1284 real = const_binop (code, t1, magsquared);
1285 imag = const_binop (code, t2, magsquared);
1289 /* Keep this algorithm in sync with
1290 tree-complex.c:expand_complex_div_wide().
1292 Expand complex division to scalars, modified algorithm to minimize
1293 overflow with wide input ranges. */
1294 tree compare = fold_build2 (LT_EXPR, boolean_type_node,
1295 fold_abs_const (r2, TREE_TYPE (type)),
1296 fold_abs_const (i2, TREE_TYPE (type)));
1298 if (integer_nonzerop (compare))
1300 /* In the TRUE branch, we compute
1302 div = (br * ratio) + bi;
1303 tr = (ar * ratio) + ai;
1304 ti = (ai * ratio) - ar;
1307 tree ratio = const_binop (code, r2, i2);
1308 tree div = const_binop (PLUS_EXPR, i2,
1309 const_binop (MULT_EXPR, r2, ratio));
1310 real = const_binop (MULT_EXPR, r1, ratio);
1311 real = const_binop (PLUS_EXPR, real, i1);
1312 real = const_binop (code, real, div);
1314 imag = const_binop (MULT_EXPR, i1, ratio);
1315 imag = const_binop (MINUS_EXPR, imag, r1);
1316 imag = const_binop (code, imag, div);
1320 /* In the FALSE branch, we compute
1322 divisor = (d * ratio) + c;
1323 tr = (b * ratio) + a;
1324 ti = b - (a * ratio);
1327 tree ratio = const_binop (code, i2, r2);
1328 tree div = const_binop (PLUS_EXPR, r2,
1329 const_binop (MULT_EXPR, i2, ratio));
1331 real = const_binop (MULT_EXPR, i1, ratio);
1332 real = const_binop (PLUS_EXPR, real, r1);
1333 real = const_binop (code, real, div);
1335 imag = const_binop (MULT_EXPR, r1, ratio);
1336 imag = const_binop (MINUS_EXPR, i1, imag);
1337 imag = const_binop (code, imag, div);
1347 return build_complex (type, real, imag);
1350 if (TREE_CODE (arg1) == VECTOR_CST)
1352 tree type = TREE_TYPE(arg1);
1353 int count = TYPE_VECTOR_SUBPARTS (type), i;
1354 tree elements1, elements2, list = NULL_TREE;
1356 if(TREE_CODE(arg2) != VECTOR_CST)
1359 elements1 = TREE_VECTOR_CST_ELTS (arg1);
1360 elements2 = TREE_VECTOR_CST_ELTS (arg2);
1362 for (i = 0; i < count; i++)
1364 tree elem1, elem2, elem;
1366 /* The trailing elements can be empty and should be treated as 0 */
1368 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1371 elem1 = TREE_VALUE(elements1);
1372 elements1 = TREE_CHAIN (elements1);
1376 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1379 elem2 = TREE_VALUE(elements2);
1380 elements2 = TREE_CHAIN (elements2);
1383 elem = const_binop (code, elem1, elem2);
1385 /* It is possible that const_binop cannot handle the given
1386 code and return NULL_TREE */
1387 if(elem == NULL_TREE)
1390 list = tree_cons (NULL_TREE, elem, list);
1392 return build_vector(type, nreverse(list));
1397 /* Create a size type INT_CST node with NUMBER sign extended. KIND
1398 indicates which particular sizetype to create. */
1401 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
1403 return build_int_cst (sizetype_tab[(int) kind], number);
1406 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
1407 is a tree code. The type of the result is taken from the operands.
1408 Both must be equivalent integer types, ala int_binop_types_match_p.
1409 If the operands are constant, so is the result. */
1412 size_binop_loc (location_t loc, enum tree_code code, tree arg0, tree arg1)
1414 tree type = TREE_TYPE (arg0);
1416 if (arg0 == error_mark_node || arg1 == error_mark_node)
1417 return error_mark_node;
1419 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
1422 /* Handle the special case of two integer constants faster. */
1423 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
1425 /* And some specific cases even faster than that. */
1426 if (code == PLUS_EXPR)
1428 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
1430 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1433 else if (code == MINUS_EXPR)
1435 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
1438 else if (code == MULT_EXPR)
1440 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
1444 /* Handle general case of two integer constants. */
1445 return int_const_binop (code, arg0, arg1, 0);
1448 return fold_build2_loc (loc, code, type, arg0, arg1);
1451 /* Given two values, either both of sizetype or both of bitsizetype,
1452 compute the difference between the two values. Return the value
1453 in signed type corresponding to the type of the operands. */
1456 size_diffop_loc (location_t loc, tree arg0, tree arg1)
1458 tree type = TREE_TYPE (arg0);
1461 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
1464 /* If the type is already signed, just do the simple thing. */
1465 if (!TYPE_UNSIGNED (type))
1466 return size_binop_loc (loc, MINUS_EXPR, arg0, arg1);
1468 if (type == sizetype)
1470 else if (type == bitsizetype)
1471 ctype = sbitsizetype;
1473 ctype = signed_type_for (type);
1475 /* If either operand is not a constant, do the conversions to the signed
1476 type and subtract. The hardware will do the right thing with any
1477 overflow in the subtraction. */
1478 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
1479 return size_binop_loc (loc, MINUS_EXPR,
1480 fold_convert_loc (loc, ctype, arg0),
1481 fold_convert_loc (loc, ctype, arg1));
1483 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
1484 Otherwise, subtract the other way, convert to CTYPE (we know that can't
1485 overflow) and negate (which can't either). Special-case a result
1486 of zero while we're here. */
1487 if (tree_int_cst_equal (arg0, arg1))
1488 return build_int_cst (ctype, 0);
1489 else if (tree_int_cst_lt (arg1, arg0))
1490 return fold_convert_loc (loc, ctype,
1491 size_binop_loc (loc, MINUS_EXPR, arg0, arg1));
1493 return size_binop_loc (loc, MINUS_EXPR, build_int_cst (ctype, 0),
1494 fold_convert_loc (loc, ctype,
1495 size_binop_loc (loc,
1500 /* A subroutine of fold_convert_const handling conversions of an
1501 INTEGER_CST to another integer type. */
1504 fold_convert_const_int_from_int (tree type, const_tree arg1)
1508 /* Given an integer constant, make new constant with new type,
1509 appropriately sign-extended or truncated. */
1510 t = force_fit_type_double (type, tree_to_double_int (arg1),
1511 !POINTER_TYPE_P (TREE_TYPE (arg1)),
1512 (TREE_INT_CST_HIGH (arg1) < 0
1513 && (TYPE_UNSIGNED (type)
1514 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1515 | TREE_OVERFLOW (arg1));
1520 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1521 to an integer type. */
1524 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
1529 /* The following code implements the floating point to integer
1530 conversion rules required by the Java Language Specification,
1531 that IEEE NaNs are mapped to zero and values that overflow
1532 the target precision saturate, i.e. values greater than
1533 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
1534 are mapped to INT_MIN. These semantics are allowed by the
1535 C and C++ standards that simply state that the behavior of
1536 FP-to-integer conversion is unspecified upon overflow. */
1540 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
1544 case FIX_TRUNC_EXPR:
1545 real_trunc (&r, VOIDmode, &x);
1552 /* If R is NaN, return zero and show we have an overflow. */
1553 if (REAL_VALUE_ISNAN (r))
1556 val = double_int_zero;
1559 /* See if R is less than the lower bound or greater than the
1564 tree lt = TYPE_MIN_VALUE (type);
1565 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
1566 if (REAL_VALUES_LESS (r, l))
1569 val = tree_to_double_int (lt);
1575 tree ut = TYPE_MAX_VALUE (type);
1578 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
1579 if (REAL_VALUES_LESS (u, r))
1582 val = tree_to_double_int (ut);
1588 real_to_integer2 ((HOST_WIDE_INT *) &val.low, &val.high, &r);
1590 t = force_fit_type_double (type, val, -1, overflow | TREE_OVERFLOW (arg1));
1594 /* A subroutine of fold_convert_const handling conversions of a
1595 FIXED_CST to an integer type. */
1598 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
1601 double_int temp, temp_trunc;
1604 /* Right shift FIXED_CST to temp by fbit. */
1605 temp = TREE_FIXED_CST (arg1).data;
1606 mode = TREE_FIXED_CST (arg1).mode;
1607 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
1609 temp = double_int_rshift (temp, GET_MODE_FBIT (mode),
1610 HOST_BITS_PER_DOUBLE_INT,
1611 SIGNED_FIXED_POINT_MODE_P (mode));
1613 /* Left shift temp to temp_trunc by fbit. */
1614 temp_trunc = double_int_lshift (temp, GET_MODE_FBIT (mode),
1615 HOST_BITS_PER_DOUBLE_INT,
1616 SIGNED_FIXED_POINT_MODE_P (mode));
1620 temp = double_int_zero;
1621 temp_trunc = double_int_zero;
1624 /* If FIXED_CST is negative, we need to round the value toward 0.
1625 By checking if the fractional bits are not zero to add 1 to temp. */
1626 if (SIGNED_FIXED_POINT_MODE_P (mode)
1627 && double_int_negative_p (temp_trunc)
1628 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
1629 temp = double_int_add (temp, double_int_one);
1631 /* Given a fixed-point constant, make new constant with new type,
1632 appropriately sign-extended or truncated. */
1633 t = force_fit_type_double (type, temp, -1,
1634 (double_int_negative_p (temp)
1635 && (TYPE_UNSIGNED (type)
1636 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
1637 | TREE_OVERFLOW (arg1));
1642 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1643 to another floating point type. */
1646 fold_convert_const_real_from_real (tree type, const_tree arg1)
1648 REAL_VALUE_TYPE value;
1651 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
1652 t = build_real (type, value);
1654 /* If converting an infinity or NAN to a representation that doesn't
1655 have one, set the overflow bit so that we can produce some kind of
1656 error message at the appropriate point if necessary. It's not the
1657 most user-friendly message, but it's better than nothing. */
1658 if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1))
1659 && !MODE_HAS_INFINITIES (TYPE_MODE (type)))
1660 TREE_OVERFLOW (t) = 1;
1661 else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
1662 && !MODE_HAS_NANS (TYPE_MODE (type)))
1663 TREE_OVERFLOW (t) = 1;
1664 /* Regular overflow, conversion produced an infinity in a mode that
1665 can't represent them. */
1666 else if (!MODE_HAS_INFINITIES (TYPE_MODE (type))
1667 && REAL_VALUE_ISINF (value)
1668 && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1)))
1669 TREE_OVERFLOW (t) = 1;
1671 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1675 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1676 to a floating point type. */
1679 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
1681 REAL_VALUE_TYPE value;
1684 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
1685 t = build_real (type, value);
1687 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
1691 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
1692 to another fixed-point type. */
1695 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
1697 FIXED_VALUE_TYPE value;
1701 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
1702 TYPE_SATURATING (type));
1703 t = build_fixed (type, value);
1705 /* Propagate overflow flags. */
1706 if (overflow_p | TREE_OVERFLOW (arg1))
1707 TREE_OVERFLOW (t) = 1;
1711 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
1712 to a fixed-point type. */
1715 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
1717 FIXED_VALUE_TYPE value;
1721 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
1722 TREE_INT_CST (arg1),
1723 TYPE_UNSIGNED (TREE_TYPE (arg1)),
1724 TYPE_SATURATING (type));
1725 t = build_fixed (type, value);
1727 /* Propagate overflow flags. */
1728 if (overflow_p | TREE_OVERFLOW (arg1))
1729 TREE_OVERFLOW (t) = 1;
1733 /* A subroutine of fold_convert_const handling conversions a REAL_CST
1734 to a fixed-point type. */
1737 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
1739 FIXED_VALUE_TYPE value;
1743 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
1744 &TREE_REAL_CST (arg1),
1745 TYPE_SATURATING (type));
1746 t = build_fixed (type, value);
1748 /* Propagate overflow flags. */
1749 if (overflow_p | TREE_OVERFLOW (arg1))
1750 TREE_OVERFLOW (t) = 1;
1754 /* Attempt to fold type conversion operation CODE of expression ARG1 to
1755 type TYPE. If no simplification can be done return NULL_TREE. */
1758 fold_convert_const (enum tree_code code, tree type, tree arg1)
1760 if (TREE_TYPE (arg1) == type)
1763 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
1764 || TREE_CODE (type) == OFFSET_TYPE)
1766 if (TREE_CODE (arg1) == INTEGER_CST)
1767 return fold_convert_const_int_from_int (type, arg1);
1768 else if (TREE_CODE (arg1) == REAL_CST)
1769 return fold_convert_const_int_from_real (code, type, arg1);
1770 else if (TREE_CODE (arg1) == FIXED_CST)
1771 return fold_convert_const_int_from_fixed (type, arg1);
1773 else if (TREE_CODE (type) == REAL_TYPE)
1775 if (TREE_CODE (arg1) == INTEGER_CST)
1776 return build_real_from_int_cst (type, arg1);
1777 else if (TREE_CODE (arg1) == REAL_CST)
1778 return fold_convert_const_real_from_real (type, arg1);
1779 else if (TREE_CODE (arg1) == FIXED_CST)
1780 return fold_convert_const_real_from_fixed (type, arg1);
1782 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
1784 if (TREE_CODE (arg1) == FIXED_CST)
1785 return fold_convert_const_fixed_from_fixed (type, arg1);
1786 else if (TREE_CODE (arg1) == INTEGER_CST)
1787 return fold_convert_const_fixed_from_int (type, arg1);
1788 else if (TREE_CODE (arg1) == REAL_CST)
1789 return fold_convert_const_fixed_from_real (type, arg1);
1794 /* Construct a vector of zero elements of vector type TYPE. */
1797 build_zero_vector (tree type)
1802 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
1803 units = TYPE_VECTOR_SUBPARTS (type);
1806 for (i = 0; i < units; i++)
1807 list = tree_cons (NULL_TREE, elem, list);
1808 return build_vector (type, list);
1811 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
1814 fold_convertible_p (const_tree type, const_tree arg)
1816 tree orig = TREE_TYPE (arg);
1821 if (TREE_CODE (arg) == ERROR_MARK
1822 || TREE_CODE (type) == ERROR_MARK
1823 || TREE_CODE (orig) == ERROR_MARK)
1826 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
1829 switch (TREE_CODE (type))
1831 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1832 case POINTER_TYPE: case REFERENCE_TYPE:
1834 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1835 || TREE_CODE (orig) == OFFSET_TYPE)
1837 return (TREE_CODE (orig) == VECTOR_TYPE
1838 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1841 case FIXED_POINT_TYPE:
1845 return TREE_CODE (type) == TREE_CODE (orig);
1852 /* Convert expression ARG to type TYPE. Used by the middle-end for
1853 simple conversions in preference to calling the front-end's convert. */
1856 fold_convert_loc (location_t loc, tree type, tree arg)
1858 tree orig = TREE_TYPE (arg);
1864 if (TREE_CODE (arg) == ERROR_MARK
1865 || TREE_CODE (type) == ERROR_MARK
1866 || TREE_CODE (orig) == ERROR_MARK)
1867 return error_mark_node;
1869 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
1870 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1872 switch (TREE_CODE (type))
1875 case REFERENCE_TYPE:
1876 /* Handle conversions between pointers to different address spaces. */
1877 if (POINTER_TYPE_P (orig)
1878 && (TYPE_ADDR_SPACE (TREE_TYPE (type))
1879 != TYPE_ADDR_SPACE (TREE_TYPE (orig))))
1880 return fold_build1_loc (loc, ADDR_SPACE_CONVERT_EXPR, type, arg);
1883 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
1885 if (TREE_CODE (arg) == INTEGER_CST)
1887 tem = fold_convert_const (NOP_EXPR, type, arg);
1888 if (tem != NULL_TREE)
1891 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
1892 || TREE_CODE (orig) == OFFSET_TYPE)
1893 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1894 if (TREE_CODE (orig) == COMPLEX_TYPE)
1895 return fold_convert_loc (loc, type,
1896 fold_build1_loc (loc, REALPART_EXPR,
1897 TREE_TYPE (orig), arg));
1898 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
1899 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
1900 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1903 if (TREE_CODE (arg) == INTEGER_CST)
1905 tem = fold_convert_const (FLOAT_EXPR, type, arg);
1906 if (tem != NULL_TREE)
1909 else if (TREE_CODE (arg) == REAL_CST)
1911 tem = fold_convert_const (NOP_EXPR, type, arg);
1912 if (tem != NULL_TREE)
1915 else if (TREE_CODE (arg) == FIXED_CST)
1917 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1918 if (tem != NULL_TREE)
1922 switch (TREE_CODE (orig))
1925 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1926 case POINTER_TYPE: case REFERENCE_TYPE:
1927 return fold_build1_loc (loc, FLOAT_EXPR, type, arg);
1930 return fold_build1_loc (loc, NOP_EXPR, type, arg);
1932 case FIXED_POINT_TYPE:
1933 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1936 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1937 return fold_convert_loc (loc, type, tem);
1943 case FIXED_POINT_TYPE:
1944 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
1945 || TREE_CODE (arg) == REAL_CST)
1947 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
1948 if (tem != NULL_TREE)
1949 goto fold_convert_exit;
1952 switch (TREE_CODE (orig))
1954 case FIXED_POINT_TYPE:
1959 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
1962 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1963 return fold_convert_loc (loc, type, tem);
1970 switch (TREE_CODE (orig))
1973 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
1974 case POINTER_TYPE: case REFERENCE_TYPE:
1976 case FIXED_POINT_TYPE:
1977 return fold_build2_loc (loc, COMPLEX_EXPR, type,
1978 fold_convert_loc (loc, TREE_TYPE (type), arg),
1979 fold_convert_loc (loc, TREE_TYPE (type),
1980 integer_zero_node));
1985 if (TREE_CODE (arg) == COMPLEX_EXPR)
1987 rpart = fold_convert_loc (loc, TREE_TYPE (type),
1988 TREE_OPERAND (arg, 0));
1989 ipart = fold_convert_loc (loc, TREE_TYPE (type),
1990 TREE_OPERAND (arg, 1));
1991 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
1994 arg = save_expr (arg);
1995 rpart = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
1996 ipart = fold_build1_loc (loc, IMAGPART_EXPR, TREE_TYPE (orig), arg);
1997 rpart = fold_convert_loc (loc, TREE_TYPE (type), rpart);
1998 ipart = fold_convert_loc (loc, TREE_TYPE (type), ipart);
1999 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2007 if (integer_zerop (arg))
2008 return build_zero_vector (type);
2009 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2010 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2011 || TREE_CODE (orig) == VECTOR_TYPE);
2012 return fold_build1_loc (loc, VIEW_CONVERT_EXPR, type, arg);
2015 tem = fold_ignored_result (arg);
2016 if (TREE_CODE (tem) == MODIFY_EXPR)
2017 goto fold_convert_exit;
2018 return fold_build1_loc (loc, NOP_EXPR, type, tem);
2024 protected_set_expr_location (tem, loc);
2028 /* Return false if expr can be assumed not to be an lvalue, true
2032 maybe_lvalue_p (const_tree x)
2034 /* We only need to wrap lvalue tree codes. */
2035 switch (TREE_CODE (x))
2048 case ARRAY_RANGE_REF:
2054 case PREINCREMENT_EXPR:
2055 case PREDECREMENT_EXPR:
2057 case TRY_CATCH_EXPR:
2058 case WITH_CLEANUP_EXPR:
2067 /* Assume the worst for front-end tree codes. */
2068 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2076 /* Return an expr equal to X but certainly not valid as an lvalue. */
2079 non_lvalue_loc (location_t loc, tree x)
2081 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2086 if (! maybe_lvalue_p (x))
2088 x = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2089 SET_EXPR_LOCATION (x, loc);
2093 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2094 Zero means allow extended lvalues. */
2096 int pedantic_lvalues;
2098 /* When pedantic, return an expr equal to X but certainly not valid as a
2099 pedantic lvalue. Otherwise, return X. */
2102 pedantic_non_lvalue_loc (location_t loc, tree x)
2104 if (pedantic_lvalues)
2105 return non_lvalue_loc (loc, x);
2106 protected_set_expr_location (x, loc);
2110 /* Given a tree comparison code, return the code that is the logical inverse
2111 of the given code. It is not safe to do this for floating-point
2112 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2113 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2116 invert_tree_comparison (enum tree_code code, bool honor_nans)
2118 if (honor_nans && flag_trapping_math)
2128 return honor_nans ? UNLE_EXPR : LE_EXPR;
2130 return honor_nans ? UNLT_EXPR : LT_EXPR;
2132 return honor_nans ? UNGE_EXPR : GE_EXPR;
2134 return honor_nans ? UNGT_EXPR : GT_EXPR;
2148 return UNORDERED_EXPR;
2149 case UNORDERED_EXPR:
2150 return ORDERED_EXPR;
2156 /* Similar, but return the comparison that results if the operands are
2157 swapped. This is safe for floating-point. */
2160 swap_tree_comparison (enum tree_code code)
2167 case UNORDERED_EXPR:
2193 /* Convert a comparison tree code from an enum tree_code representation
2194 into a compcode bit-based encoding. This function is the inverse of
2195 compcode_to_comparison. */
2197 static enum comparison_code
2198 comparison_to_compcode (enum tree_code code)
2215 return COMPCODE_ORD;
2216 case UNORDERED_EXPR:
2217 return COMPCODE_UNORD;
2219 return COMPCODE_UNLT;
2221 return COMPCODE_UNEQ;
2223 return COMPCODE_UNLE;
2225 return COMPCODE_UNGT;
2227 return COMPCODE_LTGT;
2229 return COMPCODE_UNGE;
2235 /* Convert a compcode bit-based encoding of a comparison operator back
2236 to GCC's enum tree_code representation. This function is the
2237 inverse of comparison_to_compcode. */
2239 static enum tree_code
2240 compcode_to_comparison (enum comparison_code code)
2257 return ORDERED_EXPR;
2258 case COMPCODE_UNORD:
2259 return UNORDERED_EXPR;
2277 /* Return a tree for the comparison which is the combination of
2278 doing the AND or OR (depending on CODE) of the two operations LCODE
2279 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
2280 the possibility of trapping if the mode has NaNs, and return NULL_TREE
2281 if this makes the transformation invalid. */
2284 combine_comparisons (location_t loc,
2285 enum tree_code code, enum tree_code lcode,
2286 enum tree_code rcode, tree truth_type,
2287 tree ll_arg, tree lr_arg)
2289 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
2290 enum comparison_code lcompcode = comparison_to_compcode (lcode);
2291 enum comparison_code rcompcode = comparison_to_compcode (rcode);
2296 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
2297 compcode = lcompcode & rcompcode;
2300 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
2301 compcode = lcompcode | rcompcode;
2310 /* Eliminate unordered comparisons, as well as LTGT and ORD
2311 which are not used unless the mode has NaNs. */
2312 compcode &= ~COMPCODE_UNORD;
2313 if (compcode == COMPCODE_LTGT)
2314 compcode = COMPCODE_NE;
2315 else if (compcode == COMPCODE_ORD)
2316 compcode = COMPCODE_TRUE;
2318 else if (flag_trapping_math)
2320 /* Check that the original operation and the optimized ones will trap
2321 under the same condition. */
2322 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
2323 && (lcompcode != COMPCODE_EQ)
2324 && (lcompcode != COMPCODE_ORD);
2325 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
2326 && (rcompcode != COMPCODE_EQ)
2327 && (rcompcode != COMPCODE_ORD);
2328 bool trap = (compcode & COMPCODE_UNORD) == 0
2329 && (compcode != COMPCODE_EQ)
2330 && (compcode != COMPCODE_ORD);
2332 /* In a short-circuited boolean expression the LHS might be
2333 such that the RHS, if evaluated, will never trap. For
2334 example, in ORD (x, y) && (x < y), we evaluate the RHS only
2335 if neither x nor y is NaN. (This is a mixed blessing: for
2336 example, the expression above will never trap, hence
2337 optimizing it to x < y would be invalid). */
2338 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
2339 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
2342 /* If the comparison was short-circuited, and only the RHS
2343 trapped, we may now generate a spurious trap. */
2345 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2348 /* If we changed the conditions that cause a trap, we lose. */
2349 if ((ltrap || rtrap) != trap)
2353 if (compcode == COMPCODE_TRUE)
2354 return constant_boolean_node (true, truth_type);
2355 else if (compcode == COMPCODE_FALSE)
2356 return constant_boolean_node (false, truth_type);
2359 enum tree_code tcode;
2361 tcode = compcode_to_comparison ((enum comparison_code) compcode);
2362 return fold_build2_loc (loc, tcode, truth_type, ll_arg, lr_arg);
2366 /* Return nonzero if two operands (typically of the same tree node)
2367 are necessarily equal. If either argument has side-effects this
2368 function returns zero. FLAGS modifies behavior as follows:
2370 If OEP_ONLY_CONST is set, only return nonzero for constants.
2371 This function tests whether the operands are indistinguishable;
2372 it does not test whether they are equal using C's == operation.
2373 The distinction is important for IEEE floating point, because
2374 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
2375 (2) two NaNs may be indistinguishable, but NaN!=NaN.
2377 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
2378 even though it may hold multiple values during a function.
2379 This is because a GCC tree node guarantees that nothing else is
2380 executed between the evaluation of its "operands" (which may often
2381 be evaluated in arbitrary order). Hence if the operands themselves
2382 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
2383 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
2384 unset means assuming isochronic (or instantaneous) tree equivalence.
2385 Unless comparing arbitrary expression trees, such as from different
2386 statements, this flag can usually be left unset.
2388 If OEP_PURE_SAME is set, then pure functions with identical arguments
2389 are considered the same. It is used when the caller has other ways
2390 to ensure that global memory is unchanged in between. */
2393 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
2395 /* If either is ERROR_MARK, they aren't equal. */
2396 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK
2397 || TREE_TYPE (arg0) == error_mark_node
2398 || TREE_TYPE (arg1) == error_mark_node)
2401 /* Similar, if either does not have a type (like a released SSA name),
2402 they aren't equal. */
2403 if (!TREE_TYPE (arg0) || !TREE_TYPE (arg1))
2406 /* Check equality of integer constants before bailing out due to
2407 precision differences. */
2408 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2409 return tree_int_cst_equal (arg0, arg1);
2411 /* If both types don't have the same signedness, then we can't consider
2412 them equal. We must check this before the STRIP_NOPS calls
2413 because they may change the signedness of the arguments. As pointers
2414 strictly don't have a signedness, require either two pointers or
2415 two non-pointers as well. */
2416 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
2417 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
2420 /* We cannot consider pointers to different address space equal. */
2421 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && POINTER_TYPE_P (TREE_TYPE (arg1))
2422 && (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg0)))
2423 != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg1)))))
2426 /* If both types don't have the same precision, then it is not safe
2428 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
2434 /* In case both args are comparisons but with different comparison
2435 code, try to swap the comparison operands of one arg to produce
2436 a match and compare that variant. */
2437 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2438 && COMPARISON_CLASS_P (arg0)
2439 && COMPARISON_CLASS_P (arg1))
2441 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
2443 if (TREE_CODE (arg0) == swap_code)
2444 return operand_equal_p (TREE_OPERAND (arg0, 0),
2445 TREE_OPERAND (arg1, 1), flags)
2446 && operand_equal_p (TREE_OPERAND (arg0, 1),
2447 TREE_OPERAND (arg1, 0), flags);
2450 if (TREE_CODE (arg0) != TREE_CODE (arg1)
2451 /* This is needed for conversions and for COMPONENT_REF.
2452 Might as well play it safe and always test this. */
2453 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
2454 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
2455 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
2458 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
2459 We don't care about side effects in that case because the SAVE_EXPR
2460 takes care of that for us. In all other cases, two expressions are
2461 equal if they have no side effects. If we have two identical
2462 expressions with side effects that should be treated the same due
2463 to the only side effects being identical SAVE_EXPR's, that will
2464 be detected in the recursive calls below. */
2465 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
2466 && (TREE_CODE (arg0) == SAVE_EXPR
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),
2534 if (flags & OEP_ONLY_CONST)
2537 /* Define macros to test an operand from arg0 and arg1 for equality and a
2538 variant that allows null and views null as being different from any
2539 non-null value. In the latter case, if either is null, the both
2540 must be; otherwise, do the normal comparison. */
2541 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
2542 TREE_OPERAND (arg1, N), flags)
2544 #define OP_SAME_WITH_NULL(N) \
2545 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
2546 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
2548 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
2551 /* Two conversions are equal only if signedness and modes match. */
2552 switch (TREE_CODE (arg0))
2555 case FIX_TRUNC_EXPR:
2556 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
2557 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
2567 case tcc_comparison:
2569 if (OP_SAME (0) && OP_SAME (1))
2572 /* For commutative ops, allow the other order. */
2573 return (commutative_tree_code (TREE_CODE (arg0))
2574 && operand_equal_p (TREE_OPERAND (arg0, 0),
2575 TREE_OPERAND (arg1, 1), flags)
2576 && operand_equal_p (TREE_OPERAND (arg0, 1),
2577 TREE_OPERAND (arg1, 0), flags));
2580 /* If either of the pointer (or reference) expressions we are
2581 dereferencing contain a side effect, these cannot be equal. */
2582 if (TREE_SIDE_EFFECTS (arg0)
2583 || TREE_SIDE_EFFECTS (arg1))
2586 switch (TREE_CODE (arg0))
2594 /* Require equal access sizes, and similar pointer types.
2595 We can have incomplete types for array references of
2596 variable-sized arrays from the Fortran frontent
2598 return ((TYPE_SIZE (TREE_TYPE (arg0)) == TYPE_SIZE (TREE_TYPE (arg1))
2599 || (TYPE_SIZE (TREE_TYPE (arg0))
2600 && TYPE_SIZE (TREE_TYPE (arg1))
2601 && operand_equal_p (TYPE_SIZE (TREE_TYPE (arg0)),
2602 TYPE_SIZE (TREE_TYPE (arg1)), flags)))
2603 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg0, 1)))
2604 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg1, 1))))
2605 && OP_SAME (0) && OP_SAME (1));
2608 case ARRAY_RANGE_REF:
2609 /* Operands 2 and 3 may be null.
2610 Compare the array index by value if it is constant first as we
2611 may have different types but same value here. */
2613 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
2614 TREE_OPERAND (arg1, 1))
2616 && OP_SAME_WITH_NULL (2)
2617 && OP_SAME_WITH_NULL (3));
2620 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
2621 may be NULL when we're called to compare MEM_EXPRs. */
2622 return OP_SAME_WITH_NULL (0)
2624 && OP_SAME_WITH_NULL (2);
2627 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2633 case tcc_expression:
2634 switch (TREE_CODE (arg0))
2637 case TRUTH_NOT_EXPR:
2640 case TRUTH_ANDIF_EXPR:
2641 case TRUTH_ORIF_EXPR:
2642 return OP_SAME (0) && OP_SAME (1);
2644 case TRUTH_AND_EXPR:
2646 case TRUTH_XOR_EXPR:
2647 if (OP_SAME (0) && OP_SAME (1))
2650 /* Otherwise take into account this is a commutative operation. */
2651 return (operand_equal_p (TREE_OPERAND (arg0, 0),
2652 TREE_OPERAND (arg1, 1), flags)
2653 && operand_equal_p (TREE_OPERAND (arg0, 1),
2654 TREE_OPERAND (arg1, 0), flags));
2657 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
2664 switch (TREE_CODE (arg0))
2667 /* If the CALL_EXPRs call different functions, then they
2668 clearly can not be equal. */
2669 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
2674 unsigned int cef = call_expr_flags (arg0);
2675 if (flags & OEP_PURE_SAME)
2676 cef &= ECF_CONST | ECF_PURE;
2683 /* Now see if all the arguments are the same. */
2685 const_call_expr_arg_iterator iter0, iter1;
2687 for (a0 = first_const_call_expr_arg (arg0, &iter0),
2688 a1 = first_const_call_expr_arg (arg1, &iter1);
2690 a0 = next_const_call_expr_arg (&iter0),
2691 a1 = next_const_call_expr_arg (&iter1))
2692 if (! operand_equal_p (a0, a1, flags))
2695 /* If we get here and both argument lists are exhausted
2696 then the CALL_EXPRs are equal. */
2697 return ! (a0 || a1);
2703 case tcc_declaration:
2704 /* Consider __builtin_sqrt equal to sqrt. */
2705 return (TREE_CODE (arg0) == FUNCTION_DECL
2706 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
2707 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
2708 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
2715 #undef OP_SAME_WITH_NULL
2718 /* Similar to operand_equal_p, but see if ARG0 might have been made by
2719 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
2721 When in doubt, return 0. */
2724 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
2726 int unsignedp1, unsignedpo;
2727 tree primarg0, primarg1, primother;
2728 unsigned int correct_width;
2730 if (operand_equal_p (arg0, arg1, 0))
2733 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
2734 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
2737 /* Discard any conversions that don't change the modes of ARG0 and ARG1
2738 and see if the inner values are the same. This removes any
2739 signedness comparison, which doesn't matter here. */
2740 primarg0 = arg0, primarg1 = arg1;
2741 STRIP_NOPS (primarg0);
2742 STRIP_NOPS (primarg1);
2743 if (operand_equal_p (primarg0, primarg1, 0))
2746 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
2747 actual comparison operand, ARG0.
2749 First throw away any conversions to wider types
2750 already present in the operands. */
2752 primarg1 = get_narrower (arg1, &unsignedp1);
2753 primother = get_narrower (other, &unsignedpo);
2755 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
2756 if (unsignedp1 == unsignedpo
2757 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
2758 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
2760 tree type = TREE_TYPE (arg0);
2762 /* Make sure shorter operand is extended the right way
2763 to match the longer operand. */
2764 primarg1 = fold_convert (signed_or_unsigned_type_for
2765 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
2767 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
2774 /* See if ARG is an expression that is either a comparison or is performing
2775 arithmetic on comparisons. The comparisons must only be comparing
2776 two different values, which will be stored in *CVAL1 and *CVAL2; if
2777 they are nonzero it means that some operands have already been found.
2778 No variables may be used anywhere else in the expression except in the
2779 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
2780 the expression and save_expr needs to be called with CVAL1 and CVAL2.
2782 If this is true, return 1. Otherwise, return zero. */
2785 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
2787 enum tree_code code = TREE_CODE (arg);
2788 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2790 /* We can handle some of the tcc_expression cases here. */
2791 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2793 else if (tclass == tcc_expression
2794 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
2795 || code == COMPOUND_EXPR))
2796 tclass = tcc_binary;
2798 else if (tclass == tcc_expression && code == SAVE_EXPR
2799 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
2801 /* If we've already found a CVAL1 or CVAL2, this expression is
2802 two complex to handle. */
2803 if (*cval1 || *cval2)
2813 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
2816 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
2817 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2818 cval1, cval2, save_p));
2823 case tcc_expression:
2824 if (code == COND_EXPR)
2825 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
2826 cval1, cval2, save_p)
2827 && twoval_comparison_p (TREE_OPERAND (arg, 1),
2828 cval1, cval2, save_p)
2829 && twoval_comparison_p (TREE_OPERAND (arg, 2),
2830 cval1, cval2, save_p));
2833 case tcc_comparison:
2834 /* First see if we can handle the first operand, then the second. For
2835 the second operand, we know *CVAL1 can't be zero. It must be that
2836 one side of the comparison is each of the values; test for the
2837 case where this isn't true by failing if the two operands
2840 if (operand_equal_p (TREE_OPERAND (arg, 0),
2841 TREE_OPERAND (arg, 1), 0))
2845 *cval1 = TREE_OPERAND (arg, 0);
2846 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
2848 else if (*cval2 == 0)
2849 *cval2 = TREE_OPERAND (arg, 0);
2850 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
2855 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
2857 else if (*cval2 == 0)
2858 *cval2 = TREE_OPERAND (arg, 1);
2859 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
2871 /* ARG is a tree that is known to contain just arithmetic operations and
2872 comparisons. Evaluate the operations in the tree substituting NEW0 for
2873 any occurrence of OLD0 as an operand of a comparison and likewise for
2877 eval_subst (location_t loc, tree arg, tree old0, tree new0,
2878 tree old1, tree new1)
2880 tree type = TREE_TYPE (arg);
2881 enum tree_code code = TREE_CODE (arg);
2882 enum tree_code_class tclass = TREE_CODE_CLASS (code);
2884 /* We can handle some of the tcc_expression cases here. */
2885 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
2887 else if (tclass == tcc_expression
2888 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
2889 tclass = tcc_binary;
2894 return fold_build1_loc (loc, code, type,
2895 eval_subst (loc, TREE_OPERAND (arg, 0),
2896 old0, new0, old1, new1));
2899 return fold_build2_loc (loc, code, type,
2900 eval_subst (loc, TREE_OPERAND (arg, 0),
2901 old0, new0, old1, new1),
2902 eval_subst (loc, TREE_OPERAND (arg, 1),
2903 old0, new0, old1, new1));
2905 case tcc_expression:
2909 return eval_subst (loc, TREE_OPERAND (arg, 0), old0, new0,
2913 return eval_subst (loc, TREE_OPERAND (arg, 1), old0, new0,
2917 return fold_build3_loc (loc, code, type,
2918 eval_subst (loc, TREE_OPERAND (arg, 0),
2919 old0, new0, old1, new1),
2920 eval_subst (loc, TREE_OPERAND (arg, 1),
2921 old0, new0, old1, new1),
2922 eval_subst (loc, TREE_OPERAND (arg, 2),
2923 old0, new0, old1, new1));
2927 /* Fall through - ??? */
2929 case tcc_comparison:
2931 tree arg0 = TREE_OPERAND (arg, 0);
2932 tree arg1 = TREE_OPERAND (arg, 1);
2934 /* We need to check both for exact equality and tree equality. The
2935 former will be true if the operand has a side-effect. In that
2936 case, we know the operand occurred exactly once. */
2938 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
2940 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
2943 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
2945 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
2948 return fold_build2_loc (loc, code, type, arg0, arg1);
2956 /* Return a tree for the case when the result of an expression is RESULT
2957 converted to TYPE and OMITTED was previously an operand of the expression
2958 but is now not needed (e.g., we folded OMITTED * 0).
2960 If OMITTED has side effects, we must evaluate it. Otherwise, just do
2961 the conversion of RESULT to TYPE. */
2964 omit_one_operand_loc (location_t loc, tree type, tree result, tree omitted)
2966 tree t = fold_convert_loc (loc, type, result);
2968 /* If the resulting operand is an empty statement, just return the omitted
2969 statement casted to void. */
2970 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
2972 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
2973 goto omit_one_operand_exit;
2976 if (TREE_SIDE_EFFECTS (omitted))
2978 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
2979 goto omit_one_operand_exit;
2982 return non_lvalue_loc (loc, t);
2984 omit_one_operand_exit:
2985 protected_set_expr_location (t, loc);
2989 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
2992 pedantic_omit_one_operand_loc (location_t loc, tree type, tree result,
2995 tree t = fold_convert_loc (loc, type, result);
2997 /* If the resulting operand is an empty statement, just return the omitted
2998 statement casted to void. */
2999 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3001 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3002 goto pedantic_omit_one_operand_exit;
3005 if (TREE_SIDE_EFFECTS (omitted))
3007 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3008 goto pedantic_omit_one_operand_exit;
3011 return pedantic_non_lvalue_loc (loc, t);
3013 pedantic_omit_one_operand_exit:
3014 protected_set_expr_location (t, loc);
3018 /* Return a tree for the case when the result of an expression is RESULT
3019 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3020 of the expression but are now not needed.
3022 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3023 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3024 evaluated before OMITTED2. Otherwise, if neither has side effects,
3025 just do the conversion of RESULT to TYPE. */
3028 omit_two_operands_loc (location_t loc, tree type, tree result,
3029 tree omitted1, tree omitted2)
3031 tree t = fold_convert_loc (loc, type, result);
3033 if (TREE_SIDE_EFFECTS (omitted2))
3035 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3036 SET_EXPR_LOCATION (t, loc);
3038 if (TREE_SIDE_EFFECTS (omitted1))
3040 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3041 SET_EXPR_LOCATION (t, loc);
3044 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue_loc (loc, t) : t;
3048 /* Return a simplified tree node for the truth-negation of ARG. This
3049 never alters ARG itself. We assume that ARG is an operation that
3050 returns a truth value (0 or 1).
3052 FIXME: one would think we would fold the result, but it causes
3053 problems with the dominator optimizer. */
3056 fold_truth_not_expr (location_t loc, tree arg)
3058 tree t, type = TREE_TYPE (arg);
3059 enum tree_code code = TREE_CODE (arg);
3060 location_t loc1, loc2;
3062 /* If this is a comparison, we can simply invert it, except for
3063 floating-point non-equality comparisons, in which case we just
3064 enclose a TRUTH_NOT_EXPR around what we have. */
3066 if (TREE_CODE_CLASS (code) == tcc_comparison)
3068 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3069 if (FLOAT_TYPE_P (op_type)
3070 && flag_trapping_math
3071 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3072 && code != NE_EXPR && code != EQ_EXPR)
3075 code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (op_type)));
3076 if (code == ERROR_MARK)
3079 t = build2 (code, type, TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3080 SET_EXPR_LOCATION (t, loc);
3087 return constant_boolean_node (integer_zerop (arg), type);
3089 case TRUTH_AND_EXPR:
3090 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3091 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3092 if (loc1 == UNKNOWN_LOCATION)
3094 if (loc2 == UNKNOWN_LOCATION)
3096 t = build2 (TRUTH_OR_EXPR, type,
3097 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3098 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3102 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3103 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3104 if (loc1 == UNKNOWN_LOCATION)
3106 if (loc2 == UNKNOWN_LOCATION)
3108 t = build2 (TRUTH_AND_EXPR, type,
3109 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3110 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3113 case TRUTH_XOR_EXPR:
3114 /* Here we can invert either operand. We invert the first operand
3115 unless the second operand is a TRUTH_NOT_EXPR in which case our
3116 result is the XOR of the first operand with the inside of the
3117 negation of the second operand. */
3119 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3120 t = build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3121 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3123 t = build2 (TRUTH_XOR_EXPR, type,
3124 invert_truthvalue_loc (loc, TREE_OPERAND (arg, 0)),
3125 TREE_OPERAND (arg, 1));
3128 case TRUTH_ANDIF_EXPR:
3129 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3130 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3131 if (loc1 == UNKNOWN_LOCATION)
3133 if (loc2 == UNKNOWN_LOCATION)
3135 t = build2 (TRUTH_ORIF_EXPR, type,
3136 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3137 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3140 case TRUTH_ORIF_EXPR:
3141 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3142 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3143 if (loc1 == UNKNOWN_LOCATION)
3145 if (loc2 == UNKNOWN_LOCATION)
3147 t = build2 (TRUTH_ANDIF_EXPR, type,
3148 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3149 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3152 case TRUTH_NOT_EXPR:
3153 return TREE_OPERAND (arg, 0);
3157 tree arg1 = TREE_OPERAND (arg, 1);
3158 tree arg2 = TREE_OPERAND (arg, 2);
3160 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3161 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 2));
3162 if (loc1 == UNKNOWN_LOCATION)
3164 if (loc2 == UNKNOWN_LOCATION)
3167 /* A COND_EXPR may have a throw as one operand, which
3168 then has void type. Just leave void operands
3170 t = build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3171 VOID_TYPE_P (TREE_TYPE (arg1))
3172 ? arg1 : invert_truthvalue_loc (loc1, arg1),
3173 VOID_TYPE_P (TREE_TYPE (arg2))
3174 ? arg2 : invert_truthvalue_loc (loc2, arg2));
3179 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3180 if (loc1 == UNKNOWN_LOCATION)
3182 t = build2 (COMPOUND_EXPR, type,
3183 TREE_OPERAND (arg, 0),
3184 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 1)));
3187 case NON_LVALUE_EXPR:
3188 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3189 if (loc1 == UNKNOWN_LOCATION)
3191 return invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0));
3194 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3196 t = build1 (TRUTH_NOT_EXPR, type, arg);
3200 /* ... fall through ... */
3203 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3204 if (loc1 == UNKNOWN_LOCATION)
3206 t = build1 (TREE_CODE (arg), type,
3207 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3211 if (!integer_onep (TREE_OPERAND (arg, 1)))
3213 t = build2 (EQ_EXPR, type, arg, build_int_cst (type, 0));
3217 t = build1 (TRUTH_NOT_EXPR, type, arg);
3220 case CLEANUP_POINT_EXPR:
3221 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3222 if (loc1 == UNKNOWN_LOCATION)
3224 t = build1 (CLEANUP_POINT_EXPR, type,
3225 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3234 SET_EXPR_LOCATION (t, loc);
3239 /* Return a simplified tree node for the truth-negation of ARG. This
3240 never alters ARG itself. We assume that ARG is an operation that
3241 returns a truth value (0 or 1).
3243 FIXME: one would think we would fold the result, but it causes
3244 problems with the dominator optimizer. */
3247 invert_truthvalue_loc (location_t loc, tree arg)
3251 if (TREE_CODE (arg) == ERROR_MARK)
3254 tem = fold_truth_not_expr (loc, arg);
3257 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
3258 SET_EXPR_LOCATION (tem, loc);
3264 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
3265 operands are another bit-wise operation with a common input. If so,
3266 distribute the bit operations to save an operation and possibly two if
3267 constants are involved. For example, convert
3268 (A | B) & (A | C) into A | (B & C)
3269 Further simplification will occur if B and C are constants.
3271 If this optimization cannot be done, 0 will be returned. */
3274 distribute_bit_expr (location_t loc, enum tree_code code, tree type,
3275 tree arg0, tree arg1)
3280 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3281 || TREE_CODE (arg0) == code
3282 || (TREE_CODE (arg0) != BIT_AND_EXPR
3283 && TREE_CODE (arg0) != BIT_IOR_EXPR))
3286 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
3288 common = TREE_OPERAND (arg0, 0);
3289 left = TREE_OPERAND (arg0, 1);
3290 right = TREE_OPERAND (arg1, 1);
3292 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
3294 common = TREE_OPERAND (arg0, 0);
3295 left = TREE_OPERAND (arg0, 1);
3296 right = TREE_OPERAND (arg1, 0);
3298 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
3300 common = TREE_OPERAND (arg0, 1);
3301 left = TREE_OPERAND (arg0, 0);
3302 right = TREE_OPERAND (arg1, 1);
3304 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
3306 common = TREE_OPERAND (arg0, 1);
3307 left = TREE_OPERAND (arg0, 0);
3308 right = TREE_OPERAND (arg1, 0);
3313 common = fold_convert_loc (loc, type, common);
3314 left = fold_convert_loc (loc, type, left);
3315 right = fold_convert_loc (loc, type, right);
3316 return fold_build2_loc (loc, TREE_CODE (arg0), type, common,
3317 fold_build2_loc (loc, code, type, left, right));
3320 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
3321 with code CODE. This optimization is unsafe. */
3323 distribute_real_division (location_t loc, enum tree_code code, tree type,
3324 tree arg0, tree arg1)
3326 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
3327 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
3329 /* (A / C) +- (B / C) -> (A +- B) / C. */
3331 && operand_equal_p (TREE_OPERAND (arg0, 1),
3332 TREE_OPERAND (arg1, 1), 0))
3333 return fold_build2_loc (loc, mul0 ? MULT_EXPR : RDIV_EXPR, type,
3334 fold_build2_loc (loc, code, type,
3335 TREE_OPERAND (arg0, 0),
3336 TREE_OPERAND (arg1, 0)),
3337 TREE_OPERAND (arg0, 1));
3339 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
3340 if (operand_equal_p (TREE_OPERAND (arg0, 0),
3341 TREE_OPERAND (arg1, 0), 0)
3342 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
3343 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
3345 REAL_VALUE_TYPE r0, r1;
3346 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
3347 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
3349 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
3351 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
3352 real_arithmetic (&r0, code, &r0, &r1);
3353 return fold_build2_loc (loc, MULT_EXPR, type,
3354 TREE_OPERAND (arg0, 0),
3355 build_real (type, r0));
3361 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
3362 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
3365 make_bit_field_ref (location_t loc, tree inner, tree type,
3366 HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos, int unsignedp)
3368 tree result, bftype;
3372 tree size = TYPE_SIZE (TREE_TYPE (inner));
3373 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
3374 || POINTER_TYPE_P (TREE_TYPE (inner)))
3375 && host_integerp (size, 0)
3376 && tree_low_cst (size, 0) == bitsize)
3377 return fold_convert_loc (loc, type, inner);
3381 if (TYPE_PRECISION (bftype) != bitsize
3382 || TYPE_UNSIGNED (bftype) == !unsignedp)
3383 bftype = build_nonstandard_integer_type (bitsize, 0);
3385 result = build3 (BIT_FIELD_REF, bftype, inner,
3386 size_int (bitsize), bitsize_int (bitpos));
3387 SET_EXPR_LOCATION (result, loc);
3390 result = fold_convert_loc (loc, type, result);
3395 /* Optimize a bit-field compare.
3397 There are two cases: First is a compare against a constant and the
3398 second is a comparison of two items where the fields are at the same
3399 bit position relative to the start of a chunk (byte, halfword, word)
3400 large enough to contain it. In these cases we can avoid the shift
3401 implicit in bitfield extractions.
3403 For constants, we emit a compare of the shifted constant with the
3404 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
3405 compared. For two fields at the same position, we do the ANDs with the
3406 similar mask and compare the result of the ANDs.
3408 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
3409 COMPARE_TYPE is the type of the comparison, and LHS and RHS
3410 are the left and right operands of the comparison, respectively.
3412 If the optimization described above can be done, we return the resulting
3413 tree. Otherwise we return zero. */
3416 optimize_bit_field_compare (location_t loc, enum tree_code code,
3417 tree compare_type, tree lhs, tree rhs)
3419 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
3420 tree type = TREE_TYPE (lhs);
3421 tree signed_type, unsigned_type;
3422 int const_p = TREE_CODE (rhs) == INTEGER_CST;
3423 enum machine_mode lmode, rmode, nmode;
3424 int lunsignedp, runsignedp;
3425 int lvolatilep = 0, rvolatilep = 0;
3426 tree linner, rinner = NULL_TREE;
3430 /* Get all the information about the extractions being done. If the bit size
3431 if the same as the size of the underlying object, we aren't doing an
3432 extraction at all and so can do nothing. We also don't want to
3433 do anything if the inner expression is a PLACEHOLDER_EXPR since we
3434 then will no longer be able to replace it. */
3435 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
3436 &lunsignedp, &lvolatilep, false);
3437 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
3438 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
3443 /* If this is not a constant, we can only do something if bit positions,
3444 sizes, and signedness are the same. */
3445 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
3446 &runsignedp, &rvolatilep, false);
3448 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
3449 || lunsignedp != runsignedp || offset != 0
3450 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
3454 /* See if we can find a mode to refer to this field. We should be able to,
3455 but fail if we can't. */
3457 && GET_MODE_BITSIZE (lmode) > 0
3458 && flag_strict_volatile_bitfields > 0)
3461 nmode = get_best_mode (lbitsize, lbitpos,
3462 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
3463 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
3464 TYPE_ALIGN (TREE_TYPE (rinner))),
3465 word_mode, lvolatilep || rvolatilep);
3466 if (nmode == VOIDmode)
3469 /* Set signed and unsigned types of the precision of this mode for the
3471 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
3472 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
3474 /* Compute the bit position and size for the new reference and our offset
3475 within it. If the new reference is the same size as the original, we
3476 won't optimize anything, so return zero. */
3477 nbitsize = GET_MODE_BITSIZE (nmode);
3478 nbitpos = lbitpos & ~ (nbitsize - 1);
3480 if (nbitsize == lbitsize)
3483 if (BYTES_BIG_ENDIAN)
3484 lbitpos = nbitsize - lbitsize - lbitpos;
3486 /* Make the mask to be used against the extracted field. */
3487 mask = build_int_cst_type (unsigned_type, -1);
3488 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize));
3489 mask = const_binop (RSHIFT_EXPR, mask,
3490 size_int (nbitsize - lbitsize - lbitpos));
3493 /* If not comparing with constant, just rework the comparison
3495 return fold_build2_loc (loc, code, compare_type,
3496 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3497 make_bit_field_ref (loc, linner,
3502 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3503 make_bit_field_ref (loc, rinner,
3509 /* Otherwise, we are handling the constant case. See if the constant is too
3510 big for the field. Warn and return a tree of for 0 (false) if so. We do
3511 this not only for its own sake, but to avoid having to test for this
3512 error case below. If we didn't, we might generate wrong code.
3514 For unsigned fields, the constant shifted right by the field length should
3515 be all zero. For signed fields, the high-order bits should agree with
3520 if (! integer_zerop (const_binop (RSHIFT_EXPR,
3521 fold_convert_loc (loc,
3522 unsigned_type, rhs),
3523 size_int (lbitsize))))
3525 warning (0, "comparison is always %d due to width of bit-field",
3527 return constant_boolean_node (code == NE_EXPR, compare_type);
3532 tree tem = const_binop (RSHIFT_EXPR,
3533 fold_convert_loc (loc, signed_type, rhs),
3534 size_int (lbitsize - 1));
3535 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
3537 warning (0, "comparison is always %d due to width of bit-field",
3539 return constant_boolean_node (code == NE_EXPR, compare_type);
3543 /* Single-bit compares should always be against zero. */
3544 if (lbitsize == 1 && ! integer_zerop (rhs))
3546 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
3547 rhs = build_int_cst (type, 0);
3550 /* Make a new bitfield reference, shift the constant over the
3551 appropriate number of bits and mask it with the computed mask
3552 (in case this was a signed field). If we changed it, make a new one. */
3553 lhs = make_bit_field_ref (loc, linner, unsigned_type, nbitsize, nbitpos, 1);
3556 TREE_SIDE_EFFECTS (lhs) = 1;
3557 TREE_THIS_VOLATILE (lhs) = 1;
3560 rhs = const_binop (BIT_AND_EXPR,
3561 const_binop (LSHIFT_EXPR,
3562 fold_convert_loc (loc, unsigned_type, rhs),
3563 size_int (lbitpos)),
3566 lhs = build2 (code, compare_type,
3567 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask),
3569 SET_EXPR_LOCATION (lhs, loc);
3573 /* Subroutine for fold_truthop: decode a field reference.
3575 If EXP is a comparison reference, we return the innermost reference.
3577 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
3578 set to the starting bit number.
3580 If the innermost field can be completely contained in a mode-sized
3581 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
3583 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
3584 otherwise it is not changed.
3586 *PUNSIGNEDP is set to the signedness of the field.
3588 *PMASK is set to the mask used. This is either contained in a
3589 BIT_AND_EXPR or derived from the width of the field.
3591 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
3593 Return 0 if this is not a component reference or is one that we can't
3594 do anything with. */
3597 decode_field_reference (location_t loc, tree exp, HOST_WIDE_INT *pbitsize,
3598 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
3599 int *punsignedp, int *pvolatilep,
3600 tree *pmask, tree *pand_mask)
3602 tree outer_type = 0;
3604 tree mask, inner, offset;
3606 unsigned int precision;
3608 /* All the optimizations using this function assume integer fields.
3609 There are problems with FP fields since the type_for_size call
3610 below can fail for, e.g., XFmode. */
3611 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
3614 /* We are interested in the bare arrangement of bits, so strip everything
3615 that doesn't affect the machine mode. However, record the type of the
3616 outermost expression if it may matter below. */
3617 if (CONVERT_EXPR_P (exp)
3618 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3619 outer_type = TREE_TYPE (exp);
3622 if (TREE_CODE (exp) == BIT_AND_EXPR)
3624 and_mask = TREE_OPERAND (exp, 1);
3625 exp = TREE_OPERAND (exp, 0);
3626 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
3627 if (TREE_CODE (and_mask) != INTEGER_CST)
3631 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
3632 punsignedp, pvolatilep, false);
3633 if ((inner == exp && and_mask == 0)
3634 || *pbitsize < 0 || offset != 0
3635 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
3638 /* If the number of bits in the reference is the same as the bitsize of
3639 the outer type, then the outer type gives the signedness. Otherwise
3640 (in case of a small bitfield) the signedness is unchanged. */
3641 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
3642 *punsignedp = TYPE_UNSIGNED (outer_type);
3644 /* Compute the mask to access the bitfield. */
3645 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
3646 precision = TYPE_PRECISION (unsigned_type);
3648 mask = build_int_cst_type (unsigned_type, -1);
3650 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3651 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize));
3653 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
3655 mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
3656 fold_convert_loc (loc, unsigned_type, and_mask), mask);
3659 *pand_mask = and_mask;
3663 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
3667 all_ones_mask_p (const_tree mask, int size)
3669 tree type = TREE_TYPE (mask);
3670 unsigned int precision = TYPE_PRECISION (type);
3673 tmask = build_int_cst_type (signed_type_for (type), -1);
3676 tree_int_cst_equal (mask,
3677 const_binop (RSHIFT_EXPR,
3678 const_binop (LSHIFT_EXPR, tmask,
3679 size_int (precision - size)),
3680 size_int (precision - size)));
3683 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
3684 represents the sign bit of EXP's type. If EXP represents a sign
3685 or zero extension, also test VAL against the unextended type.
3686 The return value is the (sub)expression whose sign bit is VAL,
3687 or NULL_TREE otherwise. */
3690 sign_bit_p (tree exp, const_tree val)
3692 unsigned HOST_WIDE_INT mask_lo, lo;
3693 HOST_WIDE_INT mask_hi, hi;
3697 /* Tree EXP must have an integral type. */
3698 t = TREE_TYPE (exp);
3699 if (! INTEGRAL_TYPE_P (t))
3702 /* Tree VAL must be an integer constant. */
3703 if (TREE_CODE (val) != INTEGER_CST
3704 || TREE_OVERFLOW (val))
3707 width = TYPE_PRECISION (t);
3708 if (width > HOST_BITS_PER_WIDE_INT)
3710 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
3713 mask_hi = ((unsigned HOST_WIDE_INT) -1
3714 >> (2 * HOST_BITS_PER_WIDE_INT - width));
3720 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
3723 mask_lo = ((unsigned HOST_WIDE_INT) -1
3724 >> (HOST_BITS_PER_WIDE_INT - width));
3727 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
3728 treat VAL as if it were unsigned. */
3729 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
3730 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
3733 /* Handle extension from a narrower type. */
3734 if (TREE_CODE (exp) == NOP_EXPR
3735 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
3736 return sign_bit_p (TREE_OPERAND (exp, 0), val);
3741 /* Subroutine for fold_truthop: determine if an operand is simple enough
3742 to be evaluated unconditionally. */
3745 simple_operand_p (const_tree exp)
3747 /* Strip any conversions that don't change the machine mode. */
3750 return (CONSTANT_CLASS_P (exp)
3751 || TREE_CODE (exp) == SSA_NAME
3753 && ! TREE_ADDRESSABLE (exp)
3754 && ! TREE_THIS_VOLATILE (exp)
3755 && ! DECL_NONLOCAL (exp)
3756 /* Don't regard global variables as simple. They may be
3757 allocated in ways unknown to the compiler (shared memory,
3758 #pragma weak, etc). */
3759 && ! TREE_PUBLIC (exp)
3760 && ! DECL_EXTERNAL (exp)
3761 /* Loading a static variable is unduly expensive, but global
3762 registers aren't expensive. */
3763 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
3766 /* The following functions are subroutines to fold_range_test and allow it to
3767 try to change a logical combination of comparisons into a range test.
3770 X == 2 || X == 3 || X == 4 || X == 5
3774 (unsigned) (X - 2) <= 3
3776 We describe each set of comparisons as being either inside or outside
3777 a range, using a variable named like IN_P, and then describe the
3778 range with a lower and upper bound. If one of the bounds is omitted,
3779 it represents either the highest or lowest value of the type.
3781 In the comments below, we represent a range by two numbers in brackets
3782 preceded by a "+" to designate being inside that range, or a "-" to
3783 designate being outside that range, so the condition can be inverted by
3784 flipping the prefix. An omitted bound is represented by a "-". For
3785 example, "- [-, 10]" means being outside the range starting at the lowest
3786 possible value and ending at 10, in other words, being greater than 10.
3787 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
3790 We set up things so that the missing bounds are handled in a consistent
3791 manner so neither a missing bound nor "true" and "false" need to be
3792 handled using a special case. */
3794 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
3795 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
3796 and UPPER1_P are nonzero if the respective argument is an upper bound
3797 and zero for a lower. TYPE, if nonzero, is the type of the result; it
3798 must be specified for a comparison. ARG1 will be converted to ARG0's
3799 type if both are specified. */
3802 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
3803 tree arg1, int upper1_p)
3809 /* If neither arg represents infinity, do the normal operation.
3810 Else, if not a comparison, return infinity. Else handle the special
3811 comparison rules. Note that most of the cases below won't occur, but
3812 are handled for consistency. */
3814 if (arg0 != 0 && arg1 != 0)
3816 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
3817 arg0, fold_convert (TREE_TYPE (arg0), arg1));
3819 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
3822 if (TREE_CODE_CLASS (code) != tcc_comparison)
3825 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
3826 for neither. In real maths, we cannot assume open ended ranges are
3827 the same. But, this is computer arithmetic, where numbers are finite.
3828 We can therefore make the transformation of any unbounded range with
3829 the value Z, Z being greater than any representable number. This permits
3830 us to treat unbounded ranges as equal. */
3831 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
3832 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
3836 result = sgn0 == sgn1;
3839 result = sgn0 != sgn1;
3842 result = sgn0 < sgn1;
3845 result = sgn0 <= sgn1;
3848 result = sgn0 > sgn1;
3851 result = sgn0 >= sgn1;
3857 return constant_boolean_node (result, type);
3860 /* Given EXP, a logical expression, set the range it is testing into
3861 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
3862 actually being tested. *PLOW and *PHIGH will be made of the same
3863 type as the returned expression. If EXP is not a comparison, we
3864 will most likely not be returning a useful value and range. Set
3865 *STRICT_OVERFLOW_P to true if the return value is only valid
3866 because signed overflow is undefined; otherwise, do not change
3867 *STRICT_OVERFLOW_P. */
3870 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
3871 bool *strict_overflow_p)
3873 enum tree_code code;
3874 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
3875 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
3877 tree low, high, n_low, n_high;
3878 location_t loc = EXPR_LOCATION (exp);
3880 /* Start with simply saying "EXP != 0" and then look at the code of EXP
3881 and see if we can refine the range. Some of the cases below may not
3882 happen, but it doesn't seem worth worrying about this. We "continue"
3883 the outer loop when we've changed something; otherwise we "break"
3884 the switch, which will "break" the while. */
3887 low = high = build_int_cst (TREE_TYPE (exp), 0);
3891 code = TREE_CODE (exp);
3892 exp_type = TREE_TYPE (exp);
3894 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
3896 if (TREE_OPERAND_LENGTH (exp) > 0)
3897 arg0 = TREE_OPERAND (exp, 0);
3898 if (TREE_CODE_CLASS (code) == tcc_comparison
3899 || TREE_CODE_CLASS (code) == tcc_unary
3900 || TREE_CODE_CLASS (code) == tcc_binary)
3901 arg0_type = TREE_TYPE (arg0);
3902 if (TREE_CODE_CLASS (code) == tcc_binary
3903 || TREE_CODE_CLASS (code) == tcc_comparison
3904 || (TREE_CODE_CLASS (code) == tcc_expression
3905 && TREE_OPERAND_LENGTH (exp) > 1))
3906 arg1 = TREE_OPERAND (exp, 1);
3911 case TRUTH_NOT_EXPR:
3912 in_p = ! in_p, exp = arg0;
3915 case EQ_EXPR: case NE_EXPR:
3916 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
3917 /* We can only do something if the range is testing for zero
3918 and if the second operand is an integer constant. Note that
3919 saying something is "in" the range we make is done by
3920 complementing IN_P since it will set in the initial case of
3921 being not equal to zero; "out" is leaving it alone. */
3922 if (low == 0 || high == 0
3923 || ! integer_zerop (low) || ! integer_zerop (high)
3924 || TREE_CODE (arg1) != INTEGER_CST)
3929 case NE_EXPR: /* - [c, c] */
3932 case EQ_EXPR: /* + [c, c] */
3933 in_p = ! in_p, low = high = arg1;
3935 case GT_EXPR: /* - [-, c] */
3936 low = 0, high = arg1;
3938 case GE_EXPR: /* + [c, -] */
3939 in_p = ! in_p, low = arg1, high = 0;
3941 case LT_EXPR: /* - [c, -] */
3942 low = arg1, high = 0;
3944 case LE_EXPR: /* + [-, c] */
3945 in_p = ! in_p, low = 0, high = arg1;
3951 /* If this is an unsigned comparison, we also know that EXP is
3952 greater than or equal to zero. We base the range tests we make
3953 on that fact, so we record it here so we can parse existing
3954 range tests. We test arg0_type since often the return type
3955 of, e.g. EQ_EXPR, is boolean. */
3956 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
3958 if (! merge_ranges (&n_in_p, &n_low, &n_high,
3960 build_int_cst (arg0_type, 0),
3964 in_p = n_in_p, low = n_low, high = n_high;
3966 /* If the high bound is missing, but we have a nonzero low
3967 bound, reverse the range so it goes from zero to the low bound
3969 if (high == 0 && low && ! integer_zerop (low))
3972 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
3973 integer_one_node, 0);
3974 low = build_int_cst (arg0_type, 0);
3982 /* (-x) IN [a,b] -> x in [-b, -a] */
3983 n_low = range_binop (MINUS_EXPR, exp_type,
3984 build_int_cst (exp_type, 0),
3986 n_high = range_binop (MINUS_EXPR, exp_type,
3987 build_int_cst (exp_type, 0),
3989 if (n_high != 0 && TREE_OVERFLOW (n_high))
3995 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
3996 build_int_cst (exp_type, 1));
3997 SET_EXPR_LOCATION (exp, loc);
4000 case PLUS_EXPR: case MINUS_EXPR:
4001 if (TREE_CODE (arg1) != INTEGER_CST)
4004 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4005 move a constant to the other side. */
4006 if (!TYPE_UNSIGNED (arg0_type)
4007 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4010 /* If EXP is signed, any overflow in the computation is undefined,
4011 so we don't worry about it so long as our computations on
4012 the bounds don't overflow. For unsigned, overflow is defined
4013 and this is exactly the right thing. */
4014 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4015 arg0_type, low, 0, arg1, 0);
4016 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4017 arg0_type, high, 1, arg1, 0);
4018 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4019 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4022 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4023 *strict_overflow_p = true;
4026 /* Check for an unsigned range which has wrapped around the maximum
4027 value thus making n_high < n_low, and normalize it. */
4028 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4030 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4031 integer_one_node, 0);
4032 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4033 integer_one_node, 0);
4035 /* If the range is of the form +/- [ x+1, x ], we won't
4036 be able to normalize it. But then, it represents the
4037 whole range or the empty set, so make it
4039 if (tree_int_cst_equal (n_low, low)
4040 && tree_int_cst_equal (n_high, high))
4046 low = n_low, high = n_high;
4051 CASE_CONVERT: case NON_LVALUE_EXPR:
4052 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4055 if (! INTEGRAL_TYPE_P (arg0_type)
4056 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4057 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4060 n_low = low, n_high = high;
4063 n_low = fold_convert_loc (loc, arg0_type, n_low);
4066 n_high = fold_convert_loc (loc, arg0_type, n_high);
4069 /* If we're converting arg0 from an unsigned type, to exp,
4070 a signed type, we will be doing the comparison as unsigned.
4071 The tests above have already verified that LOW and HIGH
4074 So we have to ensure that we will handle large unsigned
4075 values the same way that the current signed bounds treat
4078 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4082 /* For fixed-point modes, we need to pass the saturating flag
4083 as the 2nd parameter. */
4084 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4085 equiv_type = lang_hooks.types.type_for_mode
4086 (TYPE_MODE (arg0_type),
4087 TYPE_SATURATING (arg0_type));
4089 equiv_type = lang_hooks.types.type_for_mode
4090 (TYPE_MODE (arg0_type), 1);
4092 /* A range without an upper bound is, naturally, unbounded.
4093 Since convert would have cropped a very large value, use
4094 the max value for the destination type. */
4096 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4097 : TYPE_MAX_VALUE (arg0_type);
4099 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4100 high_positive = fold_build2_loc (loc, RSHIFT_EXPR, arg0_type,
4101 fold_convert_loc (loc, arg0_type,
4103 build_int_cst (arg0_type, 1));
4105 /* If the low bound is specified, "and" the range with the
4106 range for which the original unsigned value will be
4110 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4111 1, n_low, n_high, 1,
4112 fold_convert_loc (loc, arg0_type,
4117 in_p = (n_in_p == in_p);
4121 /* Otherwise, "or" the range with the range of the input
4122 that will be interpreted as negative. */
4123 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4124 0, n_low, n_high, 1,
4125 fold_convert_loc (loc, arg0_type,
4130 in_p = (in_p != n_in_p);
4135 low = n_low, high = n_high;
4145 /* If EXP is a constant, we can evaluate whether this is true or false. */
4146 if (TREE_CODE (exp) == INTEGER_CST)
4148 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4150 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4156 *pin_p = in_p, *plow = low, *phigh = high;
4160 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4161 type, TYPE, return an expression to test if EXP is in (or out of, depending
4162 on IN_P) the range. Return 0 if the test couldn't be created. */
4165 build_range_check (location_t loc, tree type, tree exp, int in_p,
4166 tree low, tree high)
4168 tree etype = TREE_TYPE (exp), value;
4170 #ifdef HAVE_canonicalize_funcptr_for_compare
4171 /* Disable this optimization for function pointer expressions
4172 on targets that require function pointer canonicalization. */
4173 if (HAVE_canonicalize_funcptr_for_compare
4174 && TREE_CODE (etype) == POINTER_TYPE
4175 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4181 value = build_range_check (loc, type, exp, 1, low, high);
4183 return invert_truthvalue_loc (loc, value);
4188 if (low == 0 && high == 0)
4189 return build_int_cst (type, 1);
4192 return fold_build2_loc (loc, LE_EXPR, type, exp,
4193 fold_convert_loc (loc, etype, high));
4196 return fold_build2_loc (loc, GE_EXPR, type, exp,
4197 fold_convert_loc (loc, etype, low));
4199 if (operand_equal_p (low, high, 0))
4200 return fold_build2_loc (loc, EQ_EXPR, type, exp,
4201 fold_convert_loc (loc, etype, low));
4203 if (integer_zerop (low))
4205 if (! TYPE_UNSIGNED (etype))
4207 etype = unsigned_type_for (etype);
4208 high = fold_convert_loc (loc, etype, high);
4209 exp = fold_convert_loc (loc, etype, exp);
4211 return build_range_check (loc, type, exp, 1, 0, high);
4214 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4215 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4217 unsigned HOST_WIDE_INT lo;
4221 prec = TYPE_PRECISION (etype);
4222 if (prec <= HOST_BITS_PER_WIDE_INT)
4225 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4229 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4230 lo = (unsigned HOST_WIDE_INT) -1;
4233 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4235 if (TYPE_UNSIGNED (etype))
4237 tree signed_etype = signed_type_for (etype);
4238 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4240 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4242 etype = signed_etype;
4243 exp = fold_convert_loc (loc, etype, exp);
4245 return fold_build2_loc (loc, GT_EXPR, type, exp,
4246 build_int_cst (etype, 0));
4250 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4251 This requires wrap-around arithmetics for the type of the expression.
4252 First make sure that arithmetics in this type is valid, then make sure
4253 that it wraps around. */
4254 if (TREE_CODE (etype) == ENUMERAL_TYPE || TREE_CODE (etype) == BOOLEAN_TYPE)
4255 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
4256 TYPE_UNSIGNED (etype));
4258 if (TREE_CODE (etype) == INTEGER_TYPE && !TYPE_OVERFLOW_WRAPS (etype))
4260 tree utype, minv, maxv;
4262 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
4263 for the type in question, as we rely on this here. */
4264 utype = unsigned_type_for (etype);
4265 maxv = fold_convert_loc (loc, utype, TYPE_MAX_VALUE (etype));
4266 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
4267 integer_one_node, 1);
4268 minv = fold_convert_loc (loc, utype, TYPE_MIN_VALUE (etype));
4270 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
4277 high = fold_convert_loc (loc, etype, high);
4278 low = fold_convert_loc (loc, etype, low);
4279 exp = fold_convert_loc (loc, etype, exp);
4281 value = const_binop (MINUS_EXPR, high, low);
4284 if (POINTER_TYPE_P (etype))
4286 if (value != 0 && !TREE_OVERFLOW (value))
4288 low = fold_convert_loc (loc, sizetype, low);
4289 low = fold_build1_loc (loc, NEGATE_EXPR, sizetype, low);
4290 return build_range_check (loc, type,
4291 fold_build2_loc (loc, POINTER_PLUS_EXPR,
4293 1, build_int_cst (etype, 0), value);
4298 if (value != 0 && !TREE_OVERFLOW (value))
4299 return build_range_check (loc, type,
4300 fold_build2_loc (loc, MINUS_EXPR, etype, exp, low),
4301 1, build_int_cst (etype, 0), value);
4306 /* Return the predecessor of VAL in its type, handling the infinite case. */
4309 range_predecessor (tree val)
4311 tree type = TREE_TYPE (val);
4313 if (INTEGRAL_TYPE_P (type)
4314 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
4317 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4320 /* Return the successor of VAL in its type, handling the infinite case. */
4323 range_successor (tree val)
4325 tree type = TREE_TYPE (val);
4327 if (INTEGRAL_TYPE_P (type)
4328 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
4331 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
4334 /* Given two ranges, see if we can merge them into one. Return 1 if we
4335 can, 0 if we can't. Set the output range into the specified parameters. */
4338 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
4339 tree high0, int in1_p, tree low1, tree high1)
4347 int lowequal = ((low0 == 0 && low1 == 0)
4348 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4349 low0, 0, low1, 0)));
4350 int highequal = ((high0 == 0 && high1 == 0)
4351 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
4352 high0, 1, high1, 1)));
4354 /* Make range 0 be the range that starts first, or ends last if they
4355 start at the same value. Swap them if it isn't. */
4356 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
4359 && integer_onep (range_binop (GT_EXPR, integer_type_node,
4360 high1, 1, high0, 1))))
4362 temp = in0_p, in0_p = in1_p, in1_p = temp;
4363 tem = low0, low0 = low1, low1 = tem;
4364 tem = high0, high0 = high1, high1 = tem;
4367 /* Now flag two cases, whether the ranges are disjoint or whether the
4368 second range is totally subsumed in the first. Note that the tests
4369 below are simplified by the ones above. */
4370 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
4371 high0, 1, low1, 0));
4372 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
4373 high1, 1, high0, 1));
4375 /* We now have four cases, depending on whether we are including or
4376 excluding the two ranges. */
4379 /* If they don't overlap, the result is false. If the second range
4380 is a subset it is the result. Otherwise, the range is from the start
4381 of the second to the end of the first. */
4383 in_p = 0, low = high = 0;
4385 in_p = 1, low = low1, high = high1;
4387 in_p = 1, low = low1, high = high0;
4390 else if (in0_p && ! in1_p)
4392 /* If they don't overlap, the result is the first range. If they are
4393 equal, the result is false. If the second range is a subset of the
4394 first, and the ranges begin at the same place, we go from just after
4395 the end of the second range to the end of the first. If the second
4396 range is not a subset of the first, or if it is a subset and both
4397 ranges end at the same place, the range starts at the start of the
4398 first range and ends just before the second range.
4399 Otherwise, we can't describe this as a single range. */
4401 in_p = 1, low = low0, high = high0;
4402 else if (lowequal && highequal)
4403 in_p = 0, low = high = 0;
4404 else if (subset && lowequal)
4406 low = range_successor (high1);
4411 /* We are in the weird situation where high0 > high1 but
4412 high1 has no successor. Punt. */
4416 else if (! subset || highequal)
4419 high = range_predecessor (low1);
4423 /* low0 < low1 but low1 has no predecessor. Punt. */
4431 else if (! in0_p && in1_p)
4433 /* If they don't overlap, the result is the second range. If the second
4434 is a subset of the first, the result is false. Otherwise,
4435 the range starts just after the first range and ends at the
4436 end of the second. */
4438 in_p = 1, low = low1, high = high1;
4439 else if (subset || highequal)
4440 in_p = 0, low = high = 0;
4443 low = range_successor (high0);
4448 /* high1 > high0 but high0 has no successor. Punt. */
4456 /* The case where we are excluding both ranges. Here the complex case
4457 is if they don't overlap. In that case, the only time we have a
4458 range is if they are adjacent. If the second is a subset of the
4459 first, the result is the first. Otherwise, the range to exclude
4460 starts at the beginning of the first range and ends at the end of the
4464 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
4465 range_successor (high0),
4467 in_p = 0, low = low0, high = high1;
4470 /* Canonicalize - [min, x] into - [-, x]. */
4471 if (low0 && TREE_CODE (low0) == INTEGER_CST)
4472 switch (TREE_CODE (TREE_TYPE (low0)))
4475 if (TYPE_PRECISION (TREE_TYPE (low0))
4476 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
4480 if (tree_int_cst_equal (low0,
4481 TYPE_MIN_VALUE (TREE_TYPE (low0))))
4485 if (TYPE_UNSIGNED (TREE_TYPE (low0))
4486 && integer_zerop (low0))
4493 /* Canonicalize - [x, max] into - [x, -]. */
4494 if (high1 && TREE_CODE (high1) == INTEGER_CST)
4495 switch (TREE_CODE (TREE_TYPE (high1)))
4498 if (TYPE_PRECISION (TREE_TYPE (high1))
4499 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
4503 if (tree_int_cst_equal (high1,
4504 TYPE_MAX_VALUE (TREE_TYPE (high1))))
4508 if (TYPE_UNSIGNED (TREE_TYPE (high1))
4509 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
4511 integer_one_node, 1)))
4518 /* The ranges might be also adjacent between the maximum and
4519 minimum values of the given type. For
4520 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
4521 return + [x + 1, y - 1]. */
4522 if (low0 == 0 && high1 == 0)
4524 low = range_successor (high0);
4525 high = range_predecessor (low1);
4526 if (low == 0 || high == 0)
4536 in_p = 0, low = low0, high = high0;
4538 in_p = 0, low = low0, high = high1;
4541 *pin_p = in_p, *plow = low, *phigh = high;
4546 /* Subroutine of fold, looking inside expressions of the form
4547 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
4548 of the COND_EXPR. This function is being used also to optimize
4549 A op B ? C : A, by reversing the comparison first.
4551 Return a folded expression whose code is not a COND_EXPR
4552 anymore, or NULL_TREE if no folding opportunity is found. */
4555 fold_cond_expr_with_comparison (location_t loc, tree type,
4556 tree arg0, tree arg1, tree arg2)
4558 enum tree_code comp_code = TREE_CODE (arg0);
4559 tree arg00 = TREE_OPERAND (arg0, 0);
4560 tree arg01 = TREE_OPERAND (arg0, 1);
4561 tree arg1_type = TREE_TYPE (arg1);
4567 /* If we have A op 0 ? A : -A, consider applying the following
4570 A == 0? A : -A same as -A
4571 A != 0? A : -A same as A
4572 A >= 0? A : -A same as abs (A)
4573 A > 0? A : -A same as abs (A)
4574 A <= 0? A : -A same as -abs (A)
4575 A < 0? A : -A same as -abs (A)
4577 None of these transformations work for modes with signed
4578 zeros. If A is +/-0, the first two transformations will
4579 change the sign of the result (from +0 to -0, or vice
4580 versa). The last four will fix the sign of the result,
4581 even though the original expressions could be positive or
4582 negative, depending on the sign of A.
4584 Note that all these transformations are correct if A is
4585 NaN, since the two alternatives (A and -A) are also NaNs. */
4586 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4587 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
4588 ? real_zerop (arg01)
4589 : integer_zerop (arg01))
4590 && ((TREE_CODE (arg2) == NEGATE_EXPR
4591 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
4592 /* In the case that A is of the form X-Y, '-A' (arg2) may
4593 have already been folded to Y-X, check for that. */
4594 || (TREE_CODE (arg1) == MINUS_EXPR
4595 && TREE_CODE (arg2) == MINUS_EXPR
4596 && operand_equal_p (TREE_OPERAND (arg1, 0),
4597 TREE_OPERAND (arg2, 1), 0)
4598 && operand_equal_p (TREE_OPERAND (arg1, 1),
4599 TREE_OPERAND (arg2, 0), 0))))
4604 tem = fold_convert_loc (loc, arg1_type, arg1);
4605 return pedantic_non_lvalue_loc (loc,
4606 fold_convert_loc (loc, type,
4607 negate_expr (tem)));
4610 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4613 if (flag_trapping_math)
4618 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4619 arg1 = fold_convert_loc (loc, signed_type_for
4620 (TREE_TYPE (arg1)), arg1);
4621 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4622 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4625 if (flag_trapping_math)
4629 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
4630 arg1 = fold_convert_loc (loc, signed_type_for
4631 (TREE_TYPE (arg1)), arg1);
4632 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
4633 return negate_expr (fold_convert_loc (loc, type, tem));
4635 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4639 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
4640 A == 0 ? A : 0 is always 0 unless A is -0. Note that
4641 both transformations are correct when A is NaN: A != 0
4642 is then true, and A == 0 is false. */
4644 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4645 && integer_zerop (arg01) && integer_zerop (arg2))
4647 if (comp_code == NE_EXPR)
4648 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4649 else if (comp_code == EQ_EXPR)
4650 return build_int_cst (type, 0);
4653 /* Try some transformations of A op B ? A : B.
4655 A == B? A : B same as B
4656 A != B? A : B same as A
4657 A >= B? A : B same as max (A, B)
4658 A > B? A : B same as max (B, A)
4659 A <= B? A : B same as min (A, B)
4660 A < B? A : B same as min (B, A)
4662 As above, these transformations don't work in the presence
4663 of signed zeros. For example, if A and B are zeros of
4664 opposite sign, the first two transformations will change
4665 the sign of the result. In the last four, the original
4666 expressions give different results for (A=+0, B=-0) and
4667 (A=-0, B=+0), but the transformed expressions do not.
4669 The first two transformations are correct if either A or B
4670 is a NaN. In the first transformation, the condition will
4671 be false, and B will indeed be chosen. In the case of the
4672 second transformation, the condition A != B will be true,
4673 and A will be chosen.
4675 The conversions to max() and min() are not correct if B is
4676 a number and A is not. The conditions in the original
4677 expressions will be false, so all four give B. The min()
4678 and max() versions would give a NaN instead. */
4679 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
4680 && operand_equal_for_comparison_p (arg01, arg2, arg00)
4681 /* Avoid these transformations if the COND_EXPR may be used
4682 as an lvalue in the C++ front-end. PR c++/19199. */
4684 || (strcmp (lang_hooks.name, "GNU C++") != 0
4685 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
4686 || ! maybe_lvalue_p (arg1)
4687 || ! maybe_lvalue_p (arg2)))
4689 tree comp_op0 = arg00;
4690 tree comp_op1 = arg01;
4691 tree comp_type = TREE_TYPE (comp_op0);
4693 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
4694 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
4704 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg2));
4706 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
4711 /* In C++ a ?: expression can be an lvalue, so put the
4712 operand which will be used if they are equal first
4713 so that we can convert this back to the
4714 corresponding COND_EXPR. */
4715 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4717 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4718 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4719 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
4720 ? fold_build2_loc (loc, MIN_EXPR, comp_type, comp_op0, comp_op1)
4721 : fold_build2_loc (loc, MIN_EXPR, comp_type,
4722 comp_op1, comp_op0);
4723 return pedantic_non_lvalue_loc (loc,
4724 fold_convert_loc (loc, type, tem));
4731 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4733 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
4734 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
4735 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
4736 ? fold_build2_loc (loc, MAX_EXPR, comp_type, comp_op0, comp_op1)
4737 : fold_build2_loc (loc, MAX_EXPR, comp_type,
4738 comp_op1, comp_op0);
4739 return pedantic_non_lvalue_loc (loc,
4740 fold_convert_loc (loc, type, tem));
4744 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4745 return pedantic_non_lvalue_loc (loc,
4746 fold_convert_loc (loc, type, arg2));
4749 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
4750 return pedantic_non_lvalue_loc (loc,
4751 fold_convert_loc (loc, type, arg1));
4754 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
4759 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
4760 we might still be able to simplify this. For example,
4761 if C1 is one less or one more than C2, this might have started
4762 out as a MIN or MAX and been transformed by this function.
4763 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
4765 if (INTEGRAL_TYPE_P (type)
4766 && TREE_CODE (arg01) == INTEGER_CST
4767 && TREE_CODE (arg2) == INTEGER_CST)
4771 if (TREE_CODE (arg1) == INTEGER_CST)
4773 /* We can replace A with C1 in this case. */
4774 arg1 = fold_convert_loc (loc, type, arg01);
4775 return fold_build3_loc (loc, COND_EXPR, type, arg0, arg1, arg2);
4778 /* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
4779 MIN_EXPR, to preserve the signedness of the comparison. */
4780 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4782 && operand_equal_p (arg01,
4783 const_binop (PLUS_EXPR, arg2,
4784 build_int_cst (type, 1)),
4787 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4788 fold_convert_loc (loc, TREE_TYPE (arg00),
4790 return pedantic_non_lvalue_loc (loc,
4791 fold_convert_loc (loc, type, tem));
4796 /* If C1 is C2 - 1, this is min(A, C2), with the same care
4798 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4800 && operand_equal_p (arg01,
4801 const_binop (MINUS_EXPR, arg2,
4802 build_int_cst (type, 1)),
4805 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
4806 fold_convert_loc (loc, TREE_TYPE (arg00),
4808 return pedantic_non_lvalue_loc (loc,
4809 fold_convert_loc (loc, type, tem));
4814 /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for
4815 MAX_EXPR, to preserve the signedness of the comparison. */
4816 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
4818 && operand_equal_p (arg01,
4819 const_binop (MINUS_EXPR, arg2,
4820 build_int_cst (type, 1)),
4823 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4824 fold_convert_loc (loc, TREE_TYPE (arg00),
4826 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4831 /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */
4832 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
4834 && operand_equal_p (arg01,
4835 const_binop (PLUS_EXPR, arg2,
4836 build_int_cst (type, 1)),
4839 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
4840 fold_convert_loc (loc, TREE_TYPE (arg00),
4842 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
4856 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
4857 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
4858 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
4862 /* EXP is some logical combination of boolean tests. See if we can
4863 merge it into some range test. Return the new tree if so. */
4866 fold_range_test (location_t loc, enum tree_code code, tree type,
4869 int or_op = (code == TRUTH_ORIF_EXPR
4870 || code == TRUTH_OR_EXPR);
4871 int in0_p, in1_p, in_p;
4872 tree low0, low1, low, high0, high1, high;
4873 bool strict_overflow_p = false;
4874 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
4875 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
4877 const char * const warnmsg = G_("assuming signed overflow does not occur "
4878 "when simplifying range test");
4880 /* If this is an OR operation, invert both sides; we will invert
4881 again at the end. */
4883 in0_p = ! in0_p, in1_p = ! in1_p;
4885 /* If both expressions are the same, if we can merge the ranges, and we
4886 can build the range test, return it or it inverted. If one of the
4887 ranges is always true or always false, consider it to be the same
4888 expression as the other. */
4889 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
4890 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
4892 && 0 != (tem = (build_range_check (UNKNOWN_LOCATION, type,
4894 : rhs != 0 ? rhs : integer_zero_node,
4897 if (strict_overflow_p)
4898 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
4899 return or_op ? invert_truthvalue_loc (loc, tem) : tem;
4902 /* On machines where the branch cost is expensive, if this is a
4903 short-circuited branch and the underlying object on both sides
4904 is the same, make a non-short-circuit operation. */
4905 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
4906 && lhs != 0 && rhs != 0
4907 && (code == TRUTH_ANDIF_EXPR
4908 || code == TRUTH_ORIF_EXPR)
4909 && operand_equal_p (lhs, rhs, 0))
4911 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
4912 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
4913 which cases we can't do this. */
4914 if (simple_operand_p (lhs))
4916 tem = build2 (code == TRUTH_ANDIF_EXPR
4917 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4919 SET_EXPR_LOCATION (tem, loc);
4923 else if (lang_hooks.decls.global_bindings_p () == 0
4924 && ! CONTAINS_PLACEHOLDER_P (lhs))
4926 tree common = save_expr (lhs);
4928 if (0 != (lhs = build_range_check (loc, type, common,
4929 or_op ? ! in0_p : in0_p,
4931 && (0 != (rhs = build_range_check (loc, type, common,
4932 or_op ? ! in1_p : in1_p,
4935 if (strict_overflow_p)
4936 fold_overflow_warning (warnmsg,
4937 WARN_STRICT_OVERFLOW_COMPARISON);
4938 tem = build2 (code == TRUTH_ANDIF_EXPR
4939 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
4941 SET_EXPR_LOCATION (tem, loc);
4950 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
4951 bit value. Arrange things so the extra bits will be set to zero if and
4952 only if C is signed-extended to its full width. If MASK is nonzero,
4953 it is an INTEGER_CST that should be AND'ed with the extra bits. */
4956 unextend (tree c, int p, int unsignedp, tree mask)
4958 tree type = TREE_TYPE (c);
4959 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
4962 if (p == modesize || unsignedp)
4965 /* We work by getting just the sign bit into the low-order bit, then
4966 into the high-order bit, then sign-extend. We then XOR that value
4968 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1));
4969 temp = const_binop (BIT_AND_EXPR, temp, size_int (1));
4971 /* We must use a signed type in order to get an arithmetic right shift.
4972 However, we must also avoid introducing accidental overflows, so that
4973 a subsequent call to integer_zerop will work. Hence we must
4974 do the type conversion here. At this point, the constant is either
4975 zero or one, and the conversion to a signed type can never overflow.
4976 We could get an overflow if this conversion is done anywhere else. */
4977 if (TYPE_UNSIGNED (type))
4978 temp = fold_convert (signed_type_for (type), temp);
4980 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1));
4981 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1));
4983 temp = const_binop (BIT_AND_EXPR, temp,
4984 fold_convert (TREE_TYPE (c), mask));
4985 /* If necessary, convert the type back to match the type of C. */
4986 if (TYPE_UNSIGNED (type))
4987 temp = fold_convert (type, temp);
4989 return fold_convert (type, const_binop (BIT_XOR_EXPR, c, temp));
4992 /* For an expression that has the form
4996 we can drop one of the inner expressions and simplify to
5000 LOC is the location of the resulting expression. OP is the inner
5001 logical operation; the left-hand side in the examples above, while CMPOP
5002 is the right-hand side. RHS_ONLY is used to prevent us from accidentally
5003 removing a condition that guards another, as in
5004 (A != NULL && A->...) || A == NULL
5005 which we must not transform. If RHS_ONLY is true, only eliminate the
5006 right-most operand of the inner logical operation. */
5009 merge_truthop_with_opposite_arm (location_t loc, tree op, tree cmpop,
5012 tree type = TREE_TYPE (cmpop);
5013 enum tree_code code = TREE_CODE (cmpop);
5014 enum tree_code truthop_code = TREE_CODE (op);
5015 tree lhs = TREE_OPERAND (op, 0);
5016 tree rhs = TREE_OPERAND (op, 1);
5017 tree orig_lhs = lhs, orig_rhs = rhs;
5018 enum tree_code rhs_code = TREE_CODE (rhs);
5019 enum tree_code lhs_code = TREE_CODE (lhs);
5020 enum tree_code inv_code;
5022 if (TREE_SIDE_EFFECTS (op) || TREE_SIDE_EFFECTS (cmpop))
5025 if (TREE_CODE_CLASS (code) != tcc_comparison)
5028 if (rhs_code == truthop_code)
5030 tree newrhs = merge_truthop_with_opposite_arm (loc, rhs, cmpop, rhs_only);
5031 if (newrhs != NULL_TREE)
5034 rhs_code = TREE_CODE (rhs);
5037 if (lhs_code == truthop_code && !rhs_only)
5039 tree newlhs = merge_truthop_with_opposite_arm (loc, lhs, cmpop, false);
5040 if (newlhs != NULL_TREE)
5043 lhs_code = TREE_CODE (lhs);
5047 inv_code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (type)));
5048 if (inv_code == rhs_code
5049 && operand_equal_p (TREE_OPERAND (rhs, 0), TREE_OPERAND (cmpop, 0), 0)
5050 && operand_equal_p (TREE_OPERAND (rhs, 1), TREE_OPERAND (cmpop, 1), 0))
5052 if (!rhs_only && inv_code == lhs_code
5053 && operand_equal_p (TREE_OPERAND (lhs, 0), TREE_OPERAND (cmpop, 0), 0)
5054 && operand_equal_p (TREE_OPERAND (lhs, 1), TREE_OPERAND (cmpop, 1), 0))
5056 if (rhs != orig_rhs || lhs != orig_lhs)
5057 return fold_build2_loc (loc, truthop_code, TREE_TYPE (cmpop),
5062 /* Find ways of folding logical expressions of LHS and RHS:
5063 Try to merge two comparisons to the same innermost item.
5064 Look for range tests like "ch >= '0' && ch <= '9'".
5065 Look for combinations of simple terms on machines with expensive branches
5066 and evaluate the RHS unconditionally.
5068 For example, if we have p->a == 2 && p->b == 4 and we can make an
5069 object large enough to span both A and B, we can do this with a comparison
5070 against the object ANDed with the a mask.
5072 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5073 operations to do this with one comparison.
5075 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5076 function and the one above.
5078 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5079 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5081 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5084 We return the simplified tree or 0 if no optimization is possible. */
5087 fold_truthop (location_t loc, enum tree_code code, tree truth_type,
5090 /* If this is the "or" of two comparisons, we can do something if
5091 the comparisons are NE_EXPR. If this is the "and", we can do something
5092 if the comparisons are EQ_EXPR. I.e.,
5093 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5095 WANTED_CODE is this operation code. For single bit fields, we can
5096 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5097 comparison for one-bit fields. */
5099 enum tree_code wanted_code;
5100 enum tree_code lcode, rcode;
5101 tree ll_arg, lr_arg, rl_arg, rr_arg;
5102 tree ll_inner, lr_inner, rl_inner, rr_inner;
5103 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5104 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5105 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5106 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5107 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5108 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5109 enum machine_mode lnmode, rnmode;
5110 tree ll_mask, lr_mask, rl_mask, rr_mask;
5111 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5112 tree l_const, r_const;
5113 tree lntype, rntype, result;
5114 HOST_WIDE_INT first_bit, end_bit;
5116 tree orig_lhs = lhs, orig_rhs = rhs;
5117 enum tree_code orig_code = code;
5119 /* Start by getting the comparison codes. Fail if anything is volatile.
5120 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5121 it were surrounded with a NE_EXPR. */
5123 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5126 lcode = TREE_CODE (lhs);
5127 rcode = TREE_CODE (rhs);
5129 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5131 lhs = build2 (NE_EXPR, truth_type, lhs,
5132 build_int_cst (TREE_TYPE (lhs), 0));
5136 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5138 rhs = build2 (NE_EXPR, truth_type, rhs,
5139 build_int_cst (TREE_TYPE (rhs), 0));
5143 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5144 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5147 ll_arg = TREE_OPERAND (lhs, 0);
5148 lr_arg = TREE_OPERAND (lhs, 1);
5149 rl_arg = TREE_OPERAND (rhs, 0);
5150 rr_arg = TREE_OPERAND (rhs, 1);
5152 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5153 if (simple_operand_p (ll_arg)
5154 && simple_operand_p (lr_arg))
5157 if (operand_equal_p (ll_arg, rl_arg, 0)
5158 && operand_equal_p (lr_arg, rr_arg, 0))
5160 result = combine_comparisons (loc, code, lcode, rcode,
5161 truth_type, ll_arg, lr_arg);
5165 else if (operand_equal_p (ll_arg, rr_arg, 0)
5166 && operand_equal_p (lr_arg, rl_arg, 0))
5168 result = combine_comparisons (loc, code, lcode,
5169 swap_tree_comparison (rcode),
5170 truth_type, ll_arg, lr_arg);
5176 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5177 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5179 /* If the RHS can be evaluated unconditionally and its operands are
5180 simple, it wins to evaluate the RHS unconditionally on machines
5181 with expensive branches. In this case, this isn't a comparison
5182 that can be merged. Avoid doing this if the RHS is a floating-point
5183 comparison since those can trap. */
5185 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5187 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5188 && simple_operand_p (rl_arg)
5189 && simple_operand_p (rr_arg))
5191 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5192 if (code == TRUTH_OR_EXPR
5193 && lcode == NE_EXPR && integer_zerop (lr_arg)
5194 && rcode == NE_EXPR && integer_zerop (rr_arg)
5195 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5196 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5198 result = build2 (NE_EXPR, truth_type,
5199 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5201 build_int_cst (TREE_TYPE (ll_arg), 0));
5202 goto fold_truthop_exit;
5205 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5206 if (code == TRUTH_AND_EXPR
5207 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5208 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5209 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5210 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5212 result = build2 (EQ_EXPR, truth_type,
5213 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5215 build_int_cst (TREE_TYPE (ll_arg), 0));
5216 goto fold_truthop_exit;
5219 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5221 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5223 result = build2 (code, truth_type, lhs, rhs);
5224 goto fold_truthop_exit;
5230 /* See if the comparisons can be merged. Then get all the parameters for
5233 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5234 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5238 ll_inner = decode_field_reference (loc, ll_arg,
5239 &ll_bitsize, &ll_bitpos, &ll_mode,
5240 &ll_unsignedp, &volatilep, &ll_mask,
5242 lr_inner = decode_field_reference (loc, lr_arg,
5243 &lr_bitsize, &lr_bitpos, &lr_mode,
5244 &lr_unsignedp, &volatilep, &lr_mask,
5246 rl_inner = decode_field_reference (loc, rl_arg,
5247 &rl_bitsize, &rl_bitpos, &rl_mode,
5248 &rl_unsignedp, &volatilep, &rl_mask,
5250 rr_inner = decode_field_reference (loc, rr_arg,
5251 &rr_bitsize, &rr_bitpos, &rr_mode,
5252 &rr_unsignedp, &volatilep, &rr_mask,
5255 /* It must be true that the inner operation on the lhs of each
5256 comparison must be the same if we are to be able to do anything.
5257 Then see if we have constants. If not, the same must be true for
5259 if (volatilep || ll_inner == 0 || rl_inner == 0
5260 || ! operand_equal_p (ll_inner, rl_inner, 0))
5263 if (TREE_CODE (lr_arg) == INTEGER_CST
5264 && TREE_CODE (rr_arg) == INTEGER_CST)
5265 l_const = lr_arg, r_const = rr_arg;
5266 else if (lr_inner == 0 || rr_inner == 0
5267 || ! operand_equal_p (lr_inner, rr_inner, 0))
5270 l_const = r_const = 0;
5272 /* If either comparison code is not correct for our logical operation,
5273 fail. However, we can convert a one-bit comparison against zero into
5274 the opposite comparison against that bit being set in the field. */
5276 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5277 if (lcode != wanted_code)
5279 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5281 /* Make the left operand unsigned, since we are only interested
5282 in the value of one bit. Otherwise we are doing the wrong
5291 /* This is analogous to the code for l_const above. */
5292 if (rcode != wanted_code)
5294 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5303 /* See if we can find a mode that contains both fields being compared on
5304 the left. If we can't, fail. Otherwise, update all constants and masks
5305 to be relative to a field of that size. */
5306 first_bit = MIN (ll_bitpos, rl_bitpos);
5307 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5308 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5309 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5311 if (lnmode == VOIDmode)
5314 lnbitsize = GET_MODE_BITSIZE (lnmode);
5315 lnbitpos = first_bit & ~ (lnbitsize - 1);
5316 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5317 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5319 if (BYTES_BIG_ENDIAN)
5321 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
5322 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
5325 ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
5326 size_int (xll_bitpos));
5327 rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
5328 size_int (xrl_bitpos));
5332 l_const = fold_convert_loc (loc, lntype, l_const);
5333 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
5334 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos));
5335 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
5336 fold_build1_loc (loc, BIT_NOT_EXPR,
5339 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5341 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5346 r_const = fold_convert_loc (loc, lntype, r_const);
5347 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
5348 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos));
5349 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
5350 fold_build1_loc (loc, BIT_NOT_EXPR,
5353 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
5355 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
5359 /* If the right sides are not constant, do the same for it. Also,
5360 disallow this optimization if a size or signedness mismatch occurs
5361 between the left and right sides. */
5364 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
5365 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
5366 /* Make sure the two fields on the right
5367 correspond to the left without being swapped. */
5368 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
5371 first_bit = MIN (lr_bitpos, rr_bitpos);
5372 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
5373 rnmode = get_best_mode (end_bit - first_bit, first_bit,
5374 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
5376 if (rnmode == VOIDmode)
5379 rnbitsize = GET_MODE_BITSIZE (rnmode);
5380 rnbitpos = first_bit & ~ (rnbitsize - 1);
5381 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
5382 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
5384 if (BYTES_BIG_ENDIAN)
5386 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
5387 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
5390 lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5392 size_int (xlr_bitpos));
5393 rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
5395 size_int (xrr_bitpos));
5397 /* Make a mask that corresponds to both fields being compared.
5398 Do this for both items being compared. If the operands are the
5399 same size and the bits being compared are in the same position
5400 then we can do this by masking both and comparing the masked
5402 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5403 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask);
5404 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
5406 lhs = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5407 ll_unsignedp || rl_unsignedp);
5408 if (! all_ones_mask_p (ll_mask, lnbitsize))
5409 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
5411 rhs = make_bit_field_ref (loc, lr_inner, rntype, rnbitsize, rnbitpos,
5412 lr_unsignedp || rr_unsignedp);
5413 if (! all_ones_mask_p (lr_mask, rnbitsize))
5414 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
5416 result = build2 (wanted_code, truth_type, lhs, rhs);
5417 goto fold_truthop_exit;
5420 /* There is still another way we can do something: If both pairs of
5421 fields being compared are adjacent, we may be able to make a wider
5422 field containing them both.
5424 Note that we still must mask the lhs/rhs expressions. Furthermore,
5425 the mask must be shifted to account for the shift done by
5426 make_bit_field_ref. */
5427 if ((ll_bitsize + ll_bitpos == rl_bitpos
5428 && lr_bitsize + lr_bitpos == rr_bitpos)
5429 || (ll_bitpos == rl_bitpos + rl_bitsize
5430 && lr_bitpos == rr_bitpos + rr_bitsize))
5434 lhs = make_bit_field_ref (loc, ll_inner, lntype,
5435 ll_bitsize + rl_bitsize,
5436 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
5437 rhs = make_bit_field_ref (loc, lr_inner, rntype,
5438 lr_bitsize + rr_bitsize,
5439 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
5441 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
5442 size_int (MIN (xll_bitpos, xrl_bitpos)));
5443 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
5444 size_int (MIN (xlr_bitpos, xrr_bitpos)));
5446 /* Convert to the smaller type before masking out unwanted bits. */
5448 if (lntype != rntype)
5450 if (lnbitsize > rnbitsize)
5452 lhs = fold_convert_loc (loc, rntype, lhs);
5453 ll_mask = fold_convert_loc (loc, rntype, ll_mask);
5456 else if (lnbitsize < rnbitsize)
5458 rhs = fold_convert_loc (loc, lntype, rhs);
5459 lr_mask = fold_convert_loc (loc, lntype, lr_mask);
5464 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
5465 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
5467 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
5468 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
5470 result = build2 (wanted_code, truth_type, lhs, rhs);
5471 goto fold_truthop_exit;
5477 /* Handle the case of comparisons with constants. If there is something in
5478 common between the masks, those bits of the constants must be the same.
5479 If not, the condition is always false. Test for this to avoid generating
5480 incorrect code below. */
5481 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask);
5482 if (! integer_zerop (result)
5483 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const),
5484 const_binop (BIT_AND_EXPR, result, r_const)) != 1)
5486 if (wanted_code == NE_EXPR)
5488 warning (0, "%<or%> of unmatched not-equal tests is always 1");
5489 return constant_boolean_node (true, truth_type);
5493 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
5494 return constant_boolean_node (false, truth_type);
5498 /* Construct the expression we will return. First get the component
5499 reference we will make. Unless the mask is all ones the width of
5500 that field, perform the mask operation. Then compare with the
5502 result = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
5503 ll_unsignedp || rl_unsignedp);
5505 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask);
5506 if (! all_ones_mask_p (ll_mask, lnbitsize))
5508 result = build2 (BIT_AND_EXPR, lntype, result, ll_mask);
5509 SET_EXPR_LOCATION (result, loc);
5512 result = build2 (wanted_code, truth_type, result,
5513 const_binop (BIT_IOR_EXPR, l_const, r_const));
5516 SET_EXPR_LOCATION (result, loc);
5520 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
5524 optimize_minmax_comparison (location_t loc, enum tree_code code, tree type,
5528 enum tree_code op_code;
5531 int consts_equal, consts_lt;
5534 STRIP_SIGN_NOPS (arg0);
5536 op_code = TREE_CODE (arg0);
5537 minmax_const = TREE_OPERAND (arg0, 1);
5538 comp_const = fold_convert_loc (loc, TREE_TYPE (arg0), op1);
5539 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
5540 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
5541 inner = TREE_OPERAND (arg0, 0);
5543 /* If something does not permit us to optimize, return the original tree. */
5544 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
5545 || TREE_CODE (comp_const) != INTEGER_CST
5546 || TREE_OVERFLOW (comp_const)
5547 || TREE_CODE (minmax_const) != INTEGER_CST
5548 || TREE_OVERFLOW (minmax_const))
5551 /* Now handle all the various comparison codes. We only handle EQ_EXPR
5552 and GT_EXPR, doing the rest with recursive calls using logical
5556 case NE_EXPR: case LT_EXPR: case LE_EXPR:
5559 = optimize_minmax_comparison (loc,
5560 invert_tree_comparison (code, false),
5563 return invert_truthvalue_loc (loc, tem);
5569 fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
5570 optimize_minmax_comparison
5571 (loc, EQ_EXPR, type, arg0, comp_const),
5572 optimize_minmax_comparison
5573 (loc, GT_EXPR, type, arg0, comp_const));
5576 if (op_code == MAX_EXPR && consts_equal)
5577 /* MAX (X, 0) == 0 -> X <= 0 */
5578 return fold_build2_loc (loc, LE_EXPR, type, inner, comp_const);
5580 else if (op_code == MAX_EXPR && consts_lt)
5581 /* MAX (X, 0) == 5 -> X == 5 */
5582 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5584 else if (op_code == MAX_EXPR)
5585 /* MAX (X, 0) == -1 -> false */
5586 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5588 else if (consts_equal)
5589 /* MIN (X, 0) == 0 -> X >= 0 */
5590 return fold_build2_loc (loc, GE_EXPR, type, inner, comp_const);
5593 /* MIN (X, 0) == 5 -> false */
5594 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5597 /* MIN (X, 0) == -1 -> X == -1 */
5598 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
5601 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
5602 /* MAX (X, 0) > 0 -> X > 0
5603 MAX (X, 0) > 5 -> X > 5 */
5604 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5606 else if (op_code == MAX_EXPR)
5607 /* MAX (X, 0) > -1 -> true */
5608 return omit_one_operand_loc (loc, type, integer_one_node, inner);
5610 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
5611 /* MIN (X, 0) > 0 -> false
5612 MIN (X, 0) > 5 -> false */
5613 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
5616 /* MIN (X, 0) > -1 -> X > -1 */
5617 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
5624 /* T is an integer expression that is being multiplied, divided, or taken a
5625 modulus (CODE says which and what kind of divide or modulus) by a
5626 constant C. See if we can eliminate that operation by folding it with
5627 other operations already in T. WIDE_TYPE, if non-null, is a type that
5628 should be used for the computation if wider than our type.
5630 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
5631 (X * 2) + (Y * 4). We must, however, be assured that either the original
5632 expression would not overflow or that overflow is undefined for the type
5633 in the language in question.
5635 If we return a non-null expression, it is an equivalent form of the
5636 original computation, but need not be in the original type.
5638 We set *STRICT_OVERFLOW_P to true if the return values depends on
5639 signed overflow being undefined. Otherwise we do not change
5640 *STRICT_OVERFLOW_P. */
5643 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
5644 bool *strict_overflow_p)
5646 /* To avoid exponential search depth, refuse to allow recursion past
5647 three levels. Beyond that (1) it's highly unlikely that we'll find
5648 something interesting and (2) we've probably processed it before
5649 when we built the inner expression. */
5658 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
5665 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
5666 bool *strict_overflow_p)
5668 tree type = TREE_TYPE (t);
5669 enum tree_code tcode = TREE_CODE (t);
5670 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
5671 > GET_MODE_SIZE (TYPE_MODE (type)))
5672 ? wide_type : type);
5674 int same_p = tcode == code;
5675 tree op0 = NULL_TREE, op1 = NULL_TREE;
5676 bool sub_strict_overflow_p;
5678 /* Don't deal with constants of zero here; they confuse the code below. */
5679 if (integer_zerop (c))
5682 if (TREE_CODE_CLASS (tcode) == tcc_unary)
5683 op0 = TREE_OPERAND (t, 0);
5685 if (TREE_CODE_CLASS (tcode) == tcc_binary)
5686 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
5688 /* Note that we need not handle conditional operations here since fold
5689 already handles those cases. So just do arithmetic here. */
5693 /* For a constant, we can always simplify if we are a multiply
5694 or (for divide and modulus) if it is a multiple of our constant. */
5695 if (code == MULT_EXPR
5696 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c)))
5697 return const_binop (code, fold_convert (ctype, t),
5698 fold_convert (ctype, c));
5701 CASE_CONVERT: case NON_LVALUE_EXPR:
5702 /* If op0 is an expression ... */
5703 if ((COMPARISON_CLASS_P (op0)
5704 || UNARY_CLASS_P (op0)
5705 || BINARY_CLASS_P (op0)
5706 || VL_EXP_CLASS_P (op0)
5707 || EXPRESSION_CLASS_P (op0))
5708 /* ... and has wrapping overflow, and its type is smaller
5709 than ctype, then we cannot pass through as widening. */
5710 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
5711 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
5712 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
5713 && (TYPE_PRECISION (ctype)
5714 > TYPE_PRECISION (TREE_TYPE (op0))))
5715 /* ... or this is a truncation (t is narrower than op0),
5716 then we cannot pass through this narrowing. */
5717 || (TYPE_PRECISION (type)
5718 < TYPE_PRECISION (TREE_TYPE (op0)))
5719 /* ... or signedness changes for division or modulus,
5720 then we cannot pass through this conversion. */
5721 || (code != MULT_EXPR
5722 && (TYPE_UNSIGNED (ctype)
5723 != TYPE_UNSIGNED (TREE_TYPE (op0))))
5724 /* ... or has undefined overflow while the converted to
5725 type has not, we cannot do the operation in the inner type
5726 as that would introduce undefined overflow. */
5727 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
5728 && !TYPE_OVERFLOW_UNDEFINED (type))))
5731 /* Pass the constant down and see if we can make a simplification. If
5732 we can, replace this expression with the inner simplification for
5733 possible later conversion to our or some other type. */
5734 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
5735 && TREE_CODE (t2) == INTEGER_CST
5736 && !TREE_OVERFLOW (t2)
5737 && (0 != (t1 = extract_muldiv (op0, t2, code,
5739 ? ctype : NULL_TREE,
5740 strict_overflow_p))))
5745 /* If widening the type changes it from signed to unsigned, then we
5746 must avoid building ABS_EXPR itself as unsigned. */
5747 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
5749 tree cstype = (*signed_type_for) (ctype);
5750 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
5753 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
5754 return fold_convert (ctype, t1);
5758 /* If the constant is negative, we cannot simplify this. */
5759 if (tree_int_cst_sgn (c) == -1)
5763 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
5765 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
5768 case MIN_EXPR: case MAX_EXPR:
5769 /* If widening the type changes the signedness, then we can't perform
5770 this optimization as that changes the result. */
5771 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
5774 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
5775 sub_strict_overflow_p = false;
5776 if ((t1 = extract_muldiv (op0, c, code, wide_type,
5777 &sub_strict_overflow_p)) != 0
5778 && (t2 = extract_muldiv (op1, c, code, wide_type,
5779 &sub_strict_overflow_p)) != 0)
5781 if (tree_int_cst_sgn (c) < 0)
5782 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
5783 if (sub_strict_overflow_p)
5784 *strict_overflow_p = true;
5785 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5786 fold_convert (ctype, t2));
5790 case LSHIFT_EXPR: case RSHIFT_EXPR:
5791 /* If the second operand is constant, this is a multiplication
5792 or floor division, by a power of two, so we can treat it that
5793 way unless the multiplier or divisor overflows. Signed
5794 left-shift overflow is implementation-defined rather than
5795 undefined in C90, so do not convert signed left shift into
5797 if (TREE_CODE (op1) == INTEGER_CST
5798 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
5799 /* const_binop may not detect overflow correctly,
5800 so check for it explicitly here. */
5801 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
5802 && TREE_INT_CST_HIGH (op1) == 0
5803 && 0 != (t1 = fold_convert (ctype,
5804 const_binop (LSHIFT_EXPR,
5807 && !TREE_OVERFLOW (t1))
5808 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
5809 ? MULT_EXPR : FLOOR_DIV_EXPR,
5811 fold_convert (ctype, op0),
5813 c, code, wide_type, strict_overflow_p);
5816 case PLUS_EXPR: case MINUS_EXPR:
5817 /* See if we can eliminate the operation on both sides. If we can, we
5818 can return a new PLUS or MINUS. If we can't, the only remaining
5819 cases where we can do anything are if the second operand is a
5821 sub_strict_overflow_p = false;
5822 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
5823 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
5824 if (t1 != 0 && t2 != 0
5825 && (code == MULT_EXPR
5826 /* If not multiplication, we can only do this if both operands
5827 are divisible by c. */
5828 || (multiple_of_p (ctype, op0, c)
5829 && multiple_of_p (ctype, op1, c))))
5831 if (sub_strict_overflow_p)
5832 *strict_overflow_p = true;
5833 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5834 fold_convert (ctype, t2));
5837 /* If this was a subtraction, negate OP1 and set it to be an addition.
5838 This simplifies the logic below. */
5839 if (tcode == MINUS_EXPR)
5841 tcode = PLUS_EXPR, op1 = negate_expr (op1);
5842 /* If OP1 was not easily negatable, the constant may be OP0. */
5843 if (TREE_CODE (op0) == INTEGER_CST)
5854 if (TREE_CODE (op1) != INTEGER_CST)
5857 /* If either OP1 or C are negative, this optimization is not safe for
5858 some of the division and remainder types while for others we need
5859 to change the code. */
5860 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
5862 if (code == CEIL_DIV_EXPR)
5863 code = FLOOR_DIV_EXPR;
5864 else if (code == FLOOR_DIV_EXPR)
5865 code = CEIL_DIV_EXPR;
5866 else if (code != MULT_EXPR
5867 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
5871 /* If it's a multiply or a division/modulus operation of a multiple
5872 of our constant, do the operation and verify it doesn't overflow. */
5873 if (code == MULT_EXPR
5874 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5876 op1 = const_binop (code, fold_convert (ctype, op1),
5877 fold_convert (ctype, c));
5878 /* We allow the constant to overflow with wrapping semantics. */
5880 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
5886 /* If we have an unsigned type is not a sizetype, we cannot widen
5887 the operation since it will change the result if the original
5888 computation overflowed. */
5889 if (TYPE_UNSIGNED (ctype)
5890 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
5894 /* If we were able to eliminate our operation from the first side,
5895 apply our operation to the second side and reform the PLUS. */
5896 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
5897 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
5899 /* The last case is if we are a multiply. In that case, we can
5900 apply the distributive law to commute the multiply and addition
5901 if the multiplication of the constants doesn't overflow. */
5902 if (code == MULT_EXPR)
5903 return fold_build2 (tcode, ctype,
5904 fold_build2 (code, ctype,
5905 fold_convert (ctype, op0),
5906 fold_convert (ctype, c)),
5912 /* We have a special case here if we are doing something like
5913 (C * 8) % 4 since we know that's zero. */
5914 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
5915 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
5916 /* If the multiplication can overflow we cannot optimize this.
5917 ??? Until we can properly mark individual operations as
5918 not overflowing we need to treat sizetype special here as
5919 stor-layout relies on this opimization to make
5920 DECL_FIELD_BIT_OFFSET always a constant. */
5921 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
5922 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
5923 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
5924 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
5925 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5927 *strict_overflow_p = true;
5928 return omit_one_operand (type, integer_zero_node, op0);
5931 /* ... fall through ... */
5933 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
5934 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
5935 /* If we can extract our operation from the LHS, do so and return a
5936 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
5937 do something only if the second operand is a constant. */
5939 && (t1 = extract_muldiv (op0, c, code, wide_type,
5940 strict_overflow_p)) != 0)
5941 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
5942 fold_convert (ctype, op1));
5943 else if (tcode == MULT_EXPR && code == MULT_EXPR
5944 && (t1 = extract_muldiv (op1, c, code, wide_type,
5945 strict_overflow_p)) != 0)
5946 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5947 fold_convert (ctype, t1));
5948 else if (TREE_CODE (op1) != INTEGER_CST)
5951 /* If these are the same operation types, we can associate them
5952 assuming no overflow. */
5954 && 0 != (t1 = int_const_binop (MULT_EXPR,
5955 fold_convert (ctype, op1),
5956 fold_convert (ctype, c), 1))
5957 && 0 != (t1 = force_fit_type_double (ctype, tree_to_double_int (t1),
5958 (TYPE_UNSIGNED (ctype)
5959 && tcode != MULT_EXPR) ? -1 : 1,
5960 TREE_OVERFLOW (t1)))
5961 && !TREE_OVERFLOW (t1))
5962 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
5964 /* If these operations "cancel" each other, we have the main
5965 optimizations of this pass, which occur when either constant is a
5966 multiple of the other, in which case we replace this with either an
5967 operation or CODE or TCODE.
5969 If we have an unsigned type that is not a sizetype, we cannot do
5970 this since it will change the result if the original computation
5972 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
5973 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
5974 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
5975 || (tcode == MULT_EXPR
5976 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
5977 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
5978 && code != MULT_EXPR)))
5980 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c)))
5982 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5983 *strict_overflow_p = true;
5984 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
5985 fold_convert (ctype,
5986 const_binop (TRUNC_DIV_EXPR,
5989 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1)))
5991 if (TYPE_OVERFLOW_UNDEFINED (ctype))
5992 *strict_overflow_p = true;
5993 return fold_build2 (code, ctype, fold_convert (ctype, op0),
5994 fold_convert (ctype,
5995 const_binop (TRUNC_DIV_EXPR,
6008 /* Return a node which has the indicated constant VALUE (either 0 or
6009 1), and is of the indicated TYPE. */
6012 constant_boolean_node (int value, tree type)
6014 if (type == integer_type_node)
6015 return value ? integer_one_node : integer_zero_node;
6016 else if (type == boolean_type_node)
6017 return value ? boolean_true_node : boolean_false_node;
6019 return build_int_cst (type, value);
6023 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6024 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6025 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6026 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6027 COND is the first argument to CODE; otherwise (as in the example
6028 given here), it is the second argument. TYPE is the type of the
6029 original expression. Return NULL_TREE if no simplification is
6033 fold_binary_op_with_conditional_arg (location_t loc,
6034 enum tree_code code,
6035 tree type, tree op0, tree op1,
6036 tree cond, tree arg, int cond_first_p)
6038 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6039 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6040 tree test, true_value, false_value;
6041 tree lhs = NULL_TREE;
6042 tree rhs = NULL_TREE;
6044 if (TREE_CODE (cond) == COND_EXPR)
6046 test = TREE_OPERAND (cond, 0);
6047 true_value = TREE_OPERAND (cond, 1);
6048 false_value = TREE_OPERAND (cond, 2);
6049 /* If this operand throws an expression, then it does not make
6050 sense to try to perform a logical or arithmetic operation
6052 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6054 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6059 tree testtype = TREE_TYPE (cond);
6061 true_value = constant_boolean_node (true, testtype);
6062 false_value = constant_boolean_node (false, testtype);
6065 /* This transformation is only worthwhile if we don't have to wrap ARG
6066 in a SAVE_EXPR and the operation can be simplified on at least one
6067 of the branches once its pushed inside the COND_EXPR. */
6068 if (!TREE_CONSTANT (arg)
6069 && (TREE_SIDE_EFFECTS (arg)
6070 || TREE_CONSTANT (true_value) || TREE_CONSTANT (false_value)))
6073 arg = fold_convert_loc (loc, arg_type, arg);
6076 true_value = fold_convert_loc (loc, cond_type, true_value);
6078 lhs = fold_build2_loc (loc, code, type, true_value, arg);
6080 lhs = fold_build2_loc (loc, code, type, arg, true_value);
6084 false_value = fold_convert_loc (loc, cond_type, false_value);
6086 rhs = fold_build2_loc (loc, code, type, false_value, arg);
6088 rhs = fold_build2_loc (loc, code, type, arg, false_value);
6091 /* Check that we have simplified at least one of the branches. */
6092 if (!TREE_CONSTANT (arg) && !TREE_CONSTANT (lhs) && !TREE_CONSTANT (rhs))
6095 return fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
6099 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6101 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6102 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6103 ADDEND is the same as X.
6105 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6106 and finite. The problematic cases are when X is zero, and its mode
6107 has signed zeros. In the case of rounding towards -infinity,
6108 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6109 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6112 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6114 if (!real_zerop (addend))
6117 /* Don't allow the fold with -fsignaling-nans. */
6118 if (HONOR_SNANS (TYPE_MODE (type)))
6121 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6122 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6125 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6126 if (TREE_CODE (addend) == REAL_CST
6127 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6130 /* The mode has signed zeros, and we have to honor their sign.
6131 In this situation, there is only one case we can return true for.
6132 X - 0 is the same as X unless rounding towards -infinity is
6134 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6137 /* Subroutine of fold() that checks comparisons of built-in math
6138 functions against real constants.
6140 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6141 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6142 is the type of the result and ARG0 and ARG1 are the operands of the
6143 comparison. ARG1 must be a TREE_REAL_CST.
6145 The function returns the constant folded tree if a simplification
6146 can be made, and NULL_TREE otherwise. */
6149 fold_mathfn_compare (location_t loc,
6150 enum built_in_function fcode, enum tree_code code,
6151 tree type, tree arg0, tree arg1)
6155 if (BUILTIN_SQRT_P (fcode))
6157 tree arg = CALL_EXPR_ARG (arg0, 0);
6158 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6160 c = TREE_REAL_CST (arg1);
6161 if (REAL_VALUE_NEGATIVE (c))
6163 /* sqrt(x) < y is always false, if y is negative. */
6164 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6165 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6167 /* sqrt(x) > y is always true, if y is negative and we
6168 don't care about NaNs, i.e. negative values of x. */
6169 if (code == NE_EXPR || !HONOR_NANS (mode))
6170 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6172 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6173 return fold_build2_loc (loc, GE_EXPR, type, arg,
6174 build_real (TREE_TYPE (arg), dconst0));
6176 else if (code == GT_EXPR || code == GE_EXPR)
6180 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6181 real_convert (&c2, mode, &c2);
6183 if (REAL_VALUE_ISINF (c2))
6185 /* sqrt(x) > y is x == +Inf, when y is very large. */
6186 if (HONOR_INFINITIES (mode))
6187 return fold_build2_loc (loc, EQ_EXPR, type, arg,
6188 build_real (TREE_TYPE (arg), c2));
6190 /* sqrt(x) > y is always false, when y is very large
6191 and we don't care about infinities. */
6192 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6195 /* sqrt(x) > c is the same as x > c*c. */
6196 return fold_build2_loc (loc, code, type, arg,
6197 build_real (TREE_TYPE (arg), c2));
6199 else if (code == LT_EXPR || code == LE_EXPR)
6203 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6204 real_convert (&c2, mode, &c2);
6206 if (REAL_VALUE_ISINF (c2))
6208 /* sqrt(x) < y is always true, when y is a very large
6209 value and we don't care about NaNs or Infinities. */
6210 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6211 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6213 /* sqrt(x) < y is x != +Inf when y is very large and we
6214 don't care about NaNs. */
6215 if (! HONOR_NANS (mode))
6216 return fold_build2_loc (loc, NE_EXPR, type, arg,
6217 build_real (TREE_TYPE (arg), c2));
6219 /* sqrt(x) < y is x >= 0 when y is very large and we
6220 don't care about Infinities. */
6221 if (! HONOR_INFINITIES (mode))
6222 return fold_build2_loc (loc, GE_EXPR, type, arg,
6223 build_real (TREE_TYPE (arg), dconst0));
6225 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6226 if (lang_hooks.decls.global_bindings_p () != 0
6227 || CONTAINS_PLACEHOLDER_P (arg))
6230 arg = save_expr (arg);
6231 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6232 fold_build2_loc (loc, GE_EXPR, type, arg,
6233 build_real (TREE_TYPE (arg),
6235 fold_build2_loc (loc, NE_EXPR, type, arg,
6236 build_real (TREE_TYPE (arg),
6240 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6241 if (! HONOR_NANS (mode))
6242 return fold_build2_loc (loc, code, type, arg,
6243 build_real (TREE_TYPE (arg), c2));
6245 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6246 if (lang_hooks.decls.global_bindings_p () == 0
6247 && ! CONTAINS_PLACEHOLDER_P (arg))
6249 arg = save_expr (arg);
6250 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6251 fold_build2_loc (loc, GE_EXPR, type, arg,
6252 build_real (TREE_TYPE (arg),
6254 fold_build2_loc (loc, code, type, arg,
6255 build_real (TREE_TYPE (arg),
6264 /* Subroutine of fold() that optimizes comparisons against Infinities,
6265 either +Inf or -Inf.
6267 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6268 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6269 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6271 The function returns the constant folded tree if a simplification
6272 can be made, and NULL_TREE otherwise. */
6275 fold_inf_compare (location_t loc, enum tree_code code, tree type,
6276 tree arg0, tree arg1)
6278 enum machine_mode mode;
6279 REAL_VALUE_TYPE max;
6283 mode = TYPE_MODE (TREE_TYPE (arg0));
6285 /* For negative infinity swap the sense of the comparison. */
6286 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6288 code = swap_tree_comparison (code);
6293 /* x > +Inf is always false, if with ignore sNANs. */
6294 if (HONOR_SNANS (mode))
6296 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6299 /* x <= +Inf is always true, if we don't case about NaNs. */
6300 if (! HONOR_NANS (mode))
6301 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6303 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6304 if (lang_hooks.decls.global_bindings_p () == 0
6305 && ! CONTAINS_PLACEHOLDER_P (arg0))
6307 arg0 = save_expr (arg0);
6308 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg0);
6314 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6315 real_maxval (&max, neg, mode);
6316 return fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6317 arg0, build_real (TREE_TYPE (arg0), max));
6320 /* x < +Inf is always equal to x <= DBL_MAX. */
6321 real_maxval (&max, neg, mode);
6322 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6323 arg0, build_real (TREE_TYPE (arg0), max));
6326 /* x != +Inf is always equal to !(x > DBL_MAX). */
6327 real_maxval (&max, neg, mode);
6328 if (! HONOR_NANS (mode))
6329 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
6330 arg0, build_real (TREE_TYPE (arg0), max));
6332 temp = fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6333 arg0, build_real (TREE_TYPE (arg0), max));
6334 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type, temp);
6343 /* Subroutine of fold() that optimizes comparisons of a division by
6344 a nonzero integer constant against an integer constant, i.e.
6347 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6348 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6349 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6351 The function returns the constant folded tree if a simplification
6352 can be made, and NULL_TREE otherwise. */
6355 fold_div_compare (location_t loc,
6356 enum tree_code code, tree type, tree arg0, tree arg1)
6358 tree prod, tmp, hi, lo;
6359 tree arg00 = TREE_OPERAND (arg0, 0);
6360 tree arg01 = TREE_OPERAND (arg0, 1);
6362 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
6366 /* We have to do this the hard way to detect unsigned overflow.
6367 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
6368 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
6369 TREE_INT_CST_HIGH (arg01),
6370 TREE_INT_CST_LOW (arg1),
6371 TREE_INT_CST_HIGH (arg1),
6372 &val.low, &val.high, unsigned_p);
6373 prod = force_fit_type_double (TREE_TYPE (arg00), val, -1, overflow);
6374 neg_overflow = false;
6378 tmp = int_const_binop (MINUS_EXPR, arg01,
6379 build_int_cst (TREE_TYPE (arg01), 1), 0);
6382 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
6383 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
6384 TREE_INT_CST_HIGH (prod),
6385 TREE_INT_CST_LOW (tmp),
6386 TREE_INT_CST_HIGH (tmp),
6387 &val.low, &val.high, unsigned_p);
6388 hi = force_fit_type_double (TREE_TYPE (arg00), val,
6389 -1, overflow | TREE_OVERFLOW (prod));
6391 else if (tree_int_cst_sgn (arg01) >= 0)
6393 tmp = int_const_binop (MINUS_EXPR, arg01,
6394 build_int_cst (TREE_TYPE (arg01), 1), 0);
6395 switch (tree_int_cst_sgn (arg1))
6398 neg_overflow = true;
6399 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6404 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
6409 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6419 /* A negative divisor reverses the relational operators. */
6420 code = swap_tree_comparison (code);
6422 tmp = int_const_binop (PLUS_EXPR, arg01,
6423 build_int_cst (TREE_TYPE (arg01), 1), 0);
6424 switch (tree_int_cst_sgn (arg1))
6427 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
6432 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
6437 neg_overflow = true;
6438 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
6450 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6451 return omit_one_operand_loc (loc, type, integer_zero_node, arg00);
6452 if (TREE_OVERFLOW (hi))
6453 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6454 if (TREE_OVERFLOW (lo))
6455 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6456 return build_range_check (loc, type, arg00, 1, lo, hi);
6459 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
6460 return omit_one_operand_loc (loc, type, integer_one_node, arg00);
6461 if (TREE_OVERFLOW (hi))
6462 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6463 if (TREE_OVERFLOW (lo))
6464 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6465 return build_range_check (loc, type, arg00, 0, lo, hi);
6468 if (TREE_OVERFLOW (lo))
6470 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6471 return omit_one_operand_loc (loc, type, tmp, arg00);
6473 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
6476 if (TREE_OVERFLOW (hi))
6478 tmp = neg_overflow ? integer_zero_node : integer_one_node;
6479 return omit_one_operand_loc (loc, type, tmp, arg00);
6481 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
6484 if (TREE_OVERFLOW (hi))
6486 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6487 return omit_one_operand_loc (loc, type, tmp, arg00);
6489 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
6492 if (TREE_OVERFLOW (lo))
6494 tmp = neg_overflow ? integer_one_node : integer_zero_node;
6495 return omit_one_operand_loc (loc, type, tmp, arg00);
6497 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
6507 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6508 equality/inequality test, then return a simplified form of the test
6509 using a sign testing. Otherwise return NULL. TYPE is the desired
6513 fold_single_bit_test_into_sign_test (location_t loc,
6514 enum tree_code code, tree arg0, tree arg1,
6517 /* If this is testing a single bit, we can optimize the test. */
6518 if ((code == NE_EXPR || code == EQ_EXPR)
6519 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6520 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6522 /* If we have (A & C) != 0 where C is the sign bit of A, convert
6523 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
6524 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
6526 if (arg00 != NULL_TREE
6527 /* This is only a win if casting to a signed type is cheap,
6528 i.e. when arg00's type is not a partial mode. */
6529 && TYPE_PRECISION (TREE_TYPE (arg00))
6530 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
6532 tree stype = signed_type_for (TREE_TYPE (arg00));
6533 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
6535 fold_convert_loc (loc, stype, arg00),
6536 build_int_cst (stype, 0));
6543 /* If CODE with arguments ARG0 and ARG1 represents a single bit
6544 equality/inequality test, then return a simplified form of
6545 the test using shifts and logical operations. Otherwise return
6546 NULL. TYPE is the desired result type. */
6549 fold_single_bit_test (location_t loc, enum tree_code code,
6550 tree arg0, tree arg1, tree result_type)
6552 /* If this is testing a single bit, we can optimize the test. */
6553 if ((code == NE_EXPR || code == EQ_EXPR)
6554 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
6555 && integer_pow2p (TREE_OPERAND (arg0, 1)))
6557 tree inner = TREE_OPERAND (arg0, 0);
6558 tree type = TREE_TYPE (arg0);
6559 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
6560 enum machine_mode operand_mode = TYPE_MODE (type);
6562 tree signed_type, unsigned_type, intermediate_type;
6565 /* First, see if we can fold the single bit test into a sign-bit
6567 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1,
6572 /* Otherwise we have (A & C) != 0 where C is a single bit,
6573 convert that into ((A >> C2) & 1). Where C2 = log2(C).
6574 Similarly for (A & C) == 0. */
6576 /* If INNER is a right shift of a constant and it plus BITNUM does
6577 not overflow, adjust BITNUM and INNER. */
6578 if (TREE_CODE (inner) == RSHIFT_EXPR
6579 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
6580 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
6581 && bitnum < TYPE_PRECISION (type)
6582 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
6583 bitnum - TYPE_PRECISION (type)))
6585 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
6586 inner = TREE_OPERAND (inner, 0);
6589 /* If we are going to be able to omit the AND below, we must do our
6590 operations as unsigned. If we must use the AND, we have a choice.
6591 Normally unsigned is faster, but for some machines signed is. */
6592 #ifdef LOAD_EXTEND_OP
6593 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
6594 && !flag_syntax_only) ? 0 : 1;
6599 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
6600 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
6601 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
6602 inner = fold_convert_loc (loc, intermediate_type, inner);
6605 inner = build2 (RSHIFT_EXPR, intermediate_type,
6606 inner, size_int (bitnum));
6608 one = build_int_cst (intermediate_type, 1);
6610 if (code == EQ_EXPR)
6611 inner = fold_build2_loc (loc, BIT_XOR_EXPR, intermediate_type, inner, one);
6613 /* Put the AND last so it can combine with more things. */
6614 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
6616 /* Make sure to return the proper type. */
6617 inner = fold_convert_loc (loc, result_type, inner);
6624 /* Check whether we are allowed to reorder operands arg0 and arg1,
6625 such that the evaluation of arg1 occurs before arg0. */
6628 reorder_operands_p (const_tree arg0, const_tree arg1)
6630 if (! flag_evaluation_order)
6632 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
6634 return ! TREE_SIDE_EFFECTS (arg0)
6635 && ! TREE_SIDE_EFFECTS (arg1);
6638 /* Test whether it is preferable two swap two operands, ARG0 and
6639 ARG1, for example because ARG0 is an integer constant and ARG1
6640 isn't. If REORDER is true, only recommend swapping if we can
6641 evaluate the operands in reverse order. */
6644 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
6646 STRIP_SIGN_NOPS (arg0);
6647 STRIP_SIGN_NOPS (arg1);
6649 if (TREE_CODE (arg1) == INTEGER_CST)
6651 if (TREE_CODE (arg0) == INTEGER_CST)
6654 if (TREE_CODE (arg1) == REAL_CST)
6656 if (TREE_CODE (arg0) == REAL_CST)
6659 if (TREE_CODE (arg1) == FIXED_CST)
6661 if (TREE_CODE (arg0) == FIXED_CST)
6664 if (TREE_CODE (arg1) == COMPLEX_CST)
6666 if (TREE_CODE (arg0) == COMPLEX_CST)
6669 if (TREE_CONSTANT (arg1))
6671 if (TREE_CONSTANT (arg0))
6674 if (optimize_function_for_size_p (cfun))
6677 if (reorder && flag_evaluation_order
6678 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
6681 /* It is preferable to swap two SSA_NAME to ensure a canonical form
6682 for commutative and comparison operators. Ensuring a canonical
6683 form allows the optimizers to find additional redundancies without
6684 having to explicitly check for both orderings. */
6685 if (TREE_CODE (arg0) == SSA_NAME
6686 && TREE_CODE (arg1) == SSA_NAME
6687 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
6690 /* Put SSA_NAMEs last. */
6691 if (TREE_CODE (arg1) == SSA_NAME)
6693 if (TREE_CODE (arg0) == SSA_NAME)
6696 /* Put variables last. */
6705 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
6706 ARG0 is extended to a wider type. */
6709 fold_widened_comparison (location_t loc, enum tree_code code,
6710 tree type, tree arg0, tree arg1)
6712 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
6714 tree shorter_type, outer_type;
6718 if (arg0_unw == arg0)
6720 shorter_type = TREE_TYPE (arg0_unw);
6722 #ifdef HAVE_canonicalize_funcptr_for_compare
6723 /* Disable this optimization if we're casting a function pointer
6724 type on targets that require function pointer canonicalization. */
6725 if (HAVE_canonicalize_funcptr_for_compare
6726 && TREE_CODE (shorter_type) == POINTER_TYPE
6727 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
6731 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
6734 arg1_unw = get_unwidened (arg1, NULL_TREE);
6736 /* If possible, express the comparison in the shorter mode. */
6737 if ((code == EQ_EXPR || code == NE_EXPR
6738 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
6739 && (TREE_TYPE (arg1_unw) == shorter_type
6740 || ((TYPE_PRECISION (shorter_type)
6741 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
6742 && (TYPE_UNSIGNED (shorter_type)
6743 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
6744 || (TREE_CODE (arg1_unw) == INTEGER_CST
6745 && (TREE_CODE (shorter_type) == INTEGER_TYPE
6746 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
6747 && int_fits_type_p (arg1_unw, shorter_type))))
6748 return fold_build2_loc (loc, code, type, arg0_unw,
6749 fold_convert_loc (loc, shorter_type, arg1_unw));
6751 if (TREE_CODE (arg1_unw) != INTEGER_CST
6752 || TREE_CODE (shorter_type) != INTEGER_TYPE
6753 || !int_fits_type_p (arg1_unw, shorter_type))
6756 /* If we are comparing with the integer that does not fit into the range
6757 of the shorter type, the result is known. */
6758 outer_type = TREE_TYPE (arg1_unw);
6759 min = lower_bound_in_type (outer_type, shorter_type);
6760 max = upper_bound_in_type (outer_type, shorter_type);
6762 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6764 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
6771 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6776 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6782 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6784 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6789 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6791 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6800 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
6801 ARG0 just the signedness is changed. */
6804 fold_sign_changed_comparison (location_t loc, enum tree_code code, tree type,
6805 tree arg0, tree arg1)
6808 tree inner_type, outer_type;
6810 if (!CONVERT_EXPR_P (arg0))
6813 outer_type = TREE_TYPE (arg0);
6814 arg0_inner = TREE_OPERAND (arg0, 0);
6815 inner_type = TREE_TYPE (arg0_inner);
6817 #ifdef HAVE_canonicalize_funcptr_for_compare
6818 /* Disable this optimization if we're casting a function pointer
6819 type on targets that require function pointer canonicalization. */
6820 if (HAVE_canonicalize_funcptr_for_compare
6821 && TREE_CODE (inner_type) == POINTER_TYPE
6822 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
6826 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
6829 if (TREE_CODE (arg1) != INTEGER_CST
6830 && !(CONVERT_EXPR_P (arg1)
6831 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
6834 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
6835 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
6840 if (TREE_CODE (arg1) == INTEGER_CST)
6841 arg1 = force_fit_type_double (inner_type, tree_to_double_int (arg1),
6842 0, TREE_OVERFLOW (arg1));
6844 arg1 = fold_convert_loc (loc, inner_type, arg1);
6846 return fold_build2_loc (loc, code, type, arg0_inner, arg1);
6849 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
6850 step of the array. Reconstructs s and delta in the case of s *
6851 delta being an integer constant (and thus already folded). ADDR is
6852 the address. MULT is the multiplicative expression. If the
6853 function succeeds, the new address expression is returned.
6854 Otherwise NULL_TREE is returned. LOC is the location of the
6855 resulting expression. */
6858 try_move_mult_to_index (location_t loc, tree addr, tree op1)
6860 tree s, delta, step;
6861 tree ref = TREE_OPERAND (addr, 0), pref;
6866 /* Strip the nops that might be added when converting op1 to sizetype. */
6869 /* Canonicalize op1 into a possibly non-constant delta
6870 and an INTEGER_CST s. */
6871 if (TREE_CODE (op1) == MULT_EXPR)
6873 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
6878 if (TREE_CODE (arg0) == INTEGER_CST)
6883 else if (TREE_CODE (arg1) == INTEGER_CST)
6891 else if (TREE_CODE (op1) == INTEGER_CST)
6898 /* Simulate we are delta * 1. */
6900 s = integer_one_node;
6903 for (;; ref = TREE_OPERAND (ref, 0))
6905 if (TREE_CODE (ref) == ARRAY_REF)
6909 /* Remember if this was a multi-dimensional array. */
6910 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
6913 domain = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
6916 itype = TREE_TYPE (domain);
6918 step = array_ref_element_size (ref);
6919 if (TREE_CODE (step) != INTEGER_CST)
6924 if (! tree_int_cst_equal (step, s))
6929 /* Try if delta is a multiple of step. */
6930 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
6936 /* Only fold here if we can verify we do not overflow one
6937 dimension of a multi-dimensional array. */
6942 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
6943 || !TYPE_MAX_VALUE (domain)
6944 || TREE_CODE (TYPE_MAX_VALUE (domain)) != INTEGER_CST)
6947 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
6948 fold_convert_loc (loc, itype,
6949 TREE_OPERAND (ref, 1)),
6950 fold_convert_loc (loc, itype, delta));
6952 || TREE_CODE (tmp) != INTEGER_CST
6953 || tree_int_cst_lt (TYPE_MAX_VALUE (domain), tmp))
6962 if (!handled_component_p (ref))
6966 /* We found the suitable array reference. So copy everything up to it,
6967 and replace the index. */
6969 pref = TREE_OPERAND (addr, 0);
6970 ret = copy_node (pref);
6971 SET_EXPR_LOCATION (ret, loc);
6976 pref = TREE_OPERAND (pref, 0);
6977 TREE_OPERAND (pos, 0) = copy_node (pref);
6978 pos = TREE_OPERAND (pos, 0);
6981 TREE_OPERAND (pos, 1) = fold_build2_loc (loc, PLUS_EXPR, itype,
6982 fold_convert_loc (loc, itype,
6983 TREE_OPERAND (pos, 1)),
6984 fold_convert_loc (loc, itype, delta));
6986 return fold_build1_loc (loc, ADDR_EXPR, TREE_TYPE (addr), ret);
6990 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
6991 means A >= Y && A != MAX, but in this case we know that
6992 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
6995 fold_to_nonsharp_ineq_using_bound (location_t loc, tree ineq, tree bound)
6997 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
6999 if (TREE_CODE (bound) == LT_EXPR)
7000 a = TREE_OPERAND (bound, 0);
7001 else if (TREE_CODE (bound) == GT_EXPR)
7002 a = TREE_OPERAND (bound, 1);
7006 typea = TREE_TYPE (a);
7007 if (!INTEGRAL_TYPE_P (typea)
7008 && !POINTER_TYPE_P (typea))
7011 if (TREE_CODE (ineq) == LT_EXPR)
7013 a1 = TREE_OPERAND (ineq, 1);
7014 y = TREE_OPERAND (ineq, 0);
7016 else if (TREE_CODE (ineq) == GT_EXPR)
7018 a1 = TREE_OPERAND (ineq, 0);
7019 y = TREE_OPERAND (ineq, 1);
7024 if (TREE_TYPE (a1) != typea)
7027 if (POINTER_TYPE_P (typea))
7029 /* Convert the pointer types into integer before taking the difference. */
7030 tree ta = fold_convert_loc (loc, ssizetype, a);
7031 tree ta1 = fold_convert_loc (loc, ssizetype, a1);
7032 diff = fold_binary_loc (loc, MINUS_EXPR, ssizetype, ta1, ta);
7035 diff = fold_binary_loc (loc, MINUS_EXPR, typea, a1, a);
7037 if (!diff || !integer_onep (diff))
7040 return fold_build2_loc (loc, GE_EXPR, type, a, y);
7043 /* Fold a sum or difference of at least one multiplication.
7044 Returns the folded tree or NULL if no simplification could be made. */
7047 fold_plusminus_mult_expr (location_t loc, enum tree_code code, tree type,
7048 tree arg0, tree arg1)
7050 tree arg00, arg01, arg10, arg11;
7051 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7053 /* (A * C) +- (B * C) -> (A+-B) * C.
7054 (A * C) +- A -> A * (C+-1).
7055 We are most concerned about the case where C is a constant,
7056 but other combinations show up during loop reduction. Since
7057 it is not difficult, try all four possibilities. */
7059 if (TREE_CODE (arg0) == MULT_EXPR)
7061 arg00 = TREE_OPERAND (arg0, 0);
7062 arg01 = TREE_OPERAND (arg0, 1);
7064 else if (TREE_CODE (arg0) == INTEGER_CST)
7066 arg00 = build_one_cst (type);
7071 /* We cannot generate constant 1 for fract. */
7072 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7075 arg01 = build_one_cst (type);
7077 if (TREE_CODE (arg1) == MULT_EXPR)
7079 arg10 = TREE_OPERAND (arg1, 0);
7080 arg11 = TREE_OPERAND (arg1, 1);
7082 else if (TREE_CODE (arg1) == INTEGER_CST)
7084 arg10 = build_one_cst (type);
7085 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7086 the purpose of this canonicalization. */
7087 if (TREE_INT_CST_HIGH (arg1) == -1
7088 && negate_expr_p (arg1)
7089 && code == PLUS_EXPR)
7091 arg11 = negate_expr (arg1);
7099 /* We cannot generate constant 1 for fract. */
7100 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7103 arg11 = build_one_cst (type);
7107 if (operand_equal_p (arg01, arg11, 0))
7108 same = arg01, alt0 = arg00, alt1 = arg10;
7109 else if (operand_equal_p (arg00, arg10, 0))
7110 same = arg00, alt0 = arg01, alt1 = arg11;
7111 else if (operand_equal_p (arg00, arg11, 0))
7112 same = arg00, alt0 = arg01, alt1 = arg10;
7113 else if (operand_equal_p (arg01, arg10, 0))
7114 same = arg01, alt0 = arg00, alt1 = arg11;
7116 /* No identical multiplicands; see if we can find a common
7117 power-of-two factor in non-power-of-two multiplies. This
7118 can help in multi-dimensional array access. */
7119 else if (host_integerp (arg01, 0)
7120 && host_integerp (arg11, 0))
7122 HOST_WIDE_INT int01, int11, tmp;
7125 int01 = TREE_INT_CST_LOW (arg01);
7126 int11 = TREE_INT_CST_LOW (arg11);
7128 /* Move min of absolute values to int11. */
7129 if ((int01 >= 0 ? int01 : -int01)
7130 < (int11 >= 0 ? int11 : -int11))
7132 tmp = int01, int01 = int11, int11 = tmp;
7133 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7140 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
7141 /* The remainder should not be a constant, otherwise we
7142 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7143 increased the number of multiplications necessary. */
7144 && TREE_CODE (arg10) != INTEGER_CST)
7146 alt0 = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (arg00), arg00,
7147 build_int_cst (TREE_TYPE (arg00),
7152 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7157 return fold_build2_loc (loc, MULT_EXPR, type,
7158 fold_build2_loc (loc, code, type,
7159 fold_convert_loc (loc, type, alt0),
7160 fold_convert_loc (loc, type, alt1)),
7161 fold_convert_loc (loc, type, same));
7166 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7167 specified by EXPR into the buffer PTR of length LEN bytes.
7168 Return the number of bytes placed in the buffer, or zero
7172 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7174 tree type = TREE_TYPE (expr);
7175 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7176 int byte, offset, word, words;
7177 unsigned char value;
7179 if (total_bytes > len)
7181 words = total_bytes / UNITS_PER_WORD;
7183 for (byte = 0; byte < total_bytes; byte++)
7185 int bitpos = byte * BITS_PER_UNIT;
7186 if (bitpos < HOST_BITS_PER_WIDE_INT)
7187 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7189 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7190 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7192 if (total_bytes > UNITS_PER_WORD)
7194 word = byte / UNITS_PER_WORD;
7195 if (WORDS_BIG_ENDIAN)
7196 word = (words - 1) - word;
7197 offset = word * UNITS_PER_WORD;
7198 if (BYTES_BIG_ENDIAN)
7199 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7201 offset += byte % UNITS_PER_WORD;
7204 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7205 ptr[offset] = value;
7211 /* Subroutine of native_encode_expr. Encode the REAL_CST
7212 specified by EXPR into the buffer PTR of length LEN bytes.
7213 Return the number of bytes placed in the buffer, or zero
7217 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7219 tree type = TREE_TYPE (expr);
7220 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7221 int byte, offset, word, words, bitpos;
7222 unsigned char value;
7224 /* There are always 32 bits in each long, no matter the size of
7225 the hosts long. We handle floating point representations with
7229 if (total_bytes > len)
7231 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7233 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7235 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7236 bitpos += BITS_PER_UNIT)
7238 byte = (bitpos / BITS_PER_UNIT) & 3;
7239 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7241 if (UNITS_PER_WORD < 4)
7243 word = byte / UNITS_PER_WORD;
7244 if (WORDS_BIG_ENDIAN)
7245 word = (words - 1) - word;
7246 offset = word * UNITS_PER_WORD;
7247 if (BYTES_BIG_ENDIAN)
7248 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7250 offset += byte % UNITS_PER_WORD;
7253 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7254 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7259 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7260 specified by EXPR into the buffer PTR of length LEN bytes.
7261 Return the number of bytes placed in the buffer, or zero
7265 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7270 part = TREE_REALPART (expr);
7271 rsize = native_encode_expr (part, ptr, len);
7274 part = TREE_IMAGPART (expr);
7275 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7278 return rsize + isize;
7282 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7283 specified by EXPR into the buffer PTR of length LEN bytes.
7284 Return the number of bytes placed in the buffer, or zero
7288 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7290 int i, size, offset, count;
7291 tree itype, elem, elements;
7294 elements = TREE_VECTOR_CST_ELTS (expr);
7295 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7296 itype = TREE_TYPE (TREE_TYPE (expr));
7297 size = GET_MODE_SIZE (TYPE_MODE (itype));
7298 for (i = 0; i < count; i++)
7302 elem = TREE_VALUE (elements);
7303 elements = TREE_CHAIN (elements);
7310 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7315 if (offset + size > len)
7317 memset (ptr+offset, 0, size);
7325 /* Subroutine of native_encode_expr. Encode the STRING_CST
7326 specified by EXPR into the buffer PTR of length LEN bytes.
7327 Return the number of bytes placed in the buffer, or zero
7331 native_encode_string (const_tree expr, unsigned char *ptr, int len)
7333 tree type = TREE_TYPE (expr);
7334 HOST_WIDE_INT total_bytes;
7336 if (TREE_CODE (type) != ARRAY_TYPE
7337 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
7338 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
7339 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
7341 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
7342 if (total_bytes > len)
7344 if (TREE_STRING_LENGTH (expr) < total_bytes)
7346 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
7347 memset (ptr + TREE_STRING_LENGTH (expr), 0,
7348 total_bytes - TREE_STRING_LENGTH (expr));
7351 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
7356 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
7357 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
7358 buffer PTR of length LEN bytes. Return the number of bytes
7359 placed in the buffer, or zero upon failure. */
7362 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
7364 switch (TREE_CODE (expr))
7367 return native_encode_int (expr, ptr, len);
7370 return native_encode_real (expr, ptr, len);
7373 return native_encode_complex (expr, ptr, len);
7376 return native_encode_vector (expr, ptr, len);
7379 return native_encode_string (expr, ptr, len);
7387 /* Subroutine of native_interpret_expr. Interpret the contents of
7388 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
7389 If the buffer cannot be interpreted, return NULL_TREE. */
7392 native_interpret_int (tree type, const unsigned char *ptr, int len)
7394 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7395 int byte, offset, word, words;
7396 unsigned char value;
7399 if (total_bytes > len)
7401 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
7404 result = double_int_zero;
7405 words = total_bytes / UNITS_PER_WORD;
7407 for (byte = 0; byte < total_bytes; byte++)
7409 int bitpos = byte * BITS_PER_UNIT;
7410 if (total_bytes > UNITS_PER_WORD)
7412 word = byte / UNITS_PER_WORD;
7413 if (WORDS_BIG_ENDIAN)
7414 word = (words - 1) - word;
7415 offset = word * UNITS_PER_WORD;
7416 if (BYTES_BIG_ENDIAN)
7417 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7419 offset += byte % UNITS_PER_WORD;
7422 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7423 value = ptr[offset];
7425 if (bitpos < HOST_BITS_PER_WIDE_INT)
7426 result.low |= (unsigned HOST_WIDE_INT) value << bitpos;
7428 result.high |= (unsigned HOST_WIDE_INT) value
7429 << (bitpos - HOST_BITS_PER_WIDE_INT);
7432 return double_int_to_tree (type, result);
7436 /* Subroutine of native_interpret_expr. Interpret the contents of
7437 the buffer PTR of length LEN as a REAL_CST of type TYPE.
7438 If the buffer cannot be interpreted, return NULL_TREE. */
7441 native_interpret_real (tree type, const unsigned char *ptr, int len)
7443 enum machine_mode mode = TYPE_MODE (type);
7444 int total_bytes = GET_MODE_SIZE (mode);
7445 int byte, offset, word, words, bitpos;
7446 unsigned char value;
7447 /* There are always 32 bits in each long, no matter the size of
7448 the hosts long. We handle floating point representations with
7453 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7454 if (total_bytes > len || total_bytes > 24)
7456 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7458 memset (tmp, 0, sizeof (tmp));
7459 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7460 bitpos += BITS_PER_UNIT)
7462 byte = (bitpos / BITS_PER_UNIT) & 3;
7463 if (UNITS_PER_WORD < 4)
7465 word = byte / UNITS_PER_WORD;
7466 if (WORDS_BIG_ENDIAN)
7467 word = (words - 1) - word;
7468 offset = word * UNITS_PER_WORD;
7469 if (BYTES_BIG_ENDIAN)
7470 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7472 offset += byte % UNITS_PER_WORD;
7475 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7476 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
7478 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
7481 real_from_target (&r, tmp, mode);
7482 return build_real (type, r);
7486 /* Subroutine of native_interpret_expr. Interpret the contents of
7487 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
7488 If the buffer cannot be interpreted, return NULL_TREE. */
7491 native_interpret_complex (tree type, const unsigned char *ptr, int len)
7493 tree etype, rpart, ipart;
7496 etype = TREE_TYPE (type);
7497 size = GET_MODE_SIZE (TYPE_MODE (etype));
7500 rpart = native_interpret_expr (etype, ptr, size);
7503 ipart = native_interpret_expr (etype, ptr+size, size);
7506 return build_complex (type, rpart, ipart);
7510 /* Subroutine of native_interpret_expr. Interpret the contents of
7511 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
7512 If the buffer cannot be interpreted, return NULL_TREE. */
7515 native_interpret_vector (tree type, const unsigned char *ptr, int len)
7517 tree etype, elem, elements;
7520 etype = TREE_TYPE (type);
7521 size = GET_MODE_SIZE (TYPE_MODE (etype));
7522 count = TYPE_VECTOR_SUBPARTS (type);
7523 if (size * count > len)
7526 elements = NULL_TREE;
7527 for (i = count - 1; i >= 0; i--)
7529 elem = native_interpret_expr (etype, ptr+(i*size), size);
7532 elements = tree_cons (NULL_TREE, elem, elements);
7534 return build_vector (type, elements);
7538 /* Subroutine of fold_view_convert_expr. Interpret the contents of
7539 the buffer PTR of length LEN as a constant of type TYPE. For
7540 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
7541 we return a REAL_CST, etc... If the buffer cannot be interpreted,
7542 return NULL_TREE. */
7545 native_interpret_expr (tree type, const unsigned char *ptr, int len)
7547 switch (TREE_CODE (type))
7552 return native_interpret_int (type, ptr, len);
7555 return native_interpret_real (type, ptr, len);
7558 return native_interpret_complex (type, ptr, len);
7561 return native_interpret_vector (type, ptr, len);
7569 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
7570 TYPE at compile-time. If we're unable to perform the conversion
7571 return NULL_TREE. */
7574 fold_view_convert_expr (tree type, tree expr)
7576 /* We support up to 512-bit values (for V8DFmode). */
7577 unsigned char buffer[64];
7580 /* Check that the host and target are sane. */
7581 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
7584 len = native_encode_expr (expr, buffer, sizeof (buffer));
7588 return native_interpret_expr (type, buffer, len);
7591 /* Build an expression for the address of T. Folds away INDIRECT_REF
7592 to avoid confusing the gimplify process. */
7595 build_fold_addr_expr_with_type_loc (location_t loc, tree t, tree ptrtype)
7597 /* The size of the object is not relevant when talking about its address. */
7598 if (TREE_CODE (t) == WITH_SIZE_EXPR)
7599 t = TREE_OPERAND (t, 0);
7601 if (TREE_CODE (t) == INDIRECT_REF)
7603 t = TREE_OPERAND (t, 0);
7605 if (TREE_TYPE (t) != ptrtype)
7607 t = build1 (NOP_EXPR, ptrtype, t);
7608 SET_EXPR_LOCATION (t, loc);
7611 else if (TREE_CODE (t) == MEM_REF
7612 && integer_zerop (TREE_OPERAND (t, 1)))
7613 return TREE_OPERAND (t, 0);
7614 else if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
7616 t = build_fold_addr_expr_loc (loc, TREE_OPERAND (t, 0));
7618 if (TREE_TYPE (t) != ptrtype)
7619 t = fold_convert_loc (loc, ptrtype, t);
7623 t = build1 (ADDR_EXPR, ptrtype, t);
7624 SET_EXPR_LOCATION (t, loc);
7630 /* Build an expression for the address of T. */
7633 build_fold_addr_expr_loc (location_t loc, tree t)
7635 tree ptrtype = build_pointer_type (TREE_TYPE (t));
7637 return build_fold_addr_expr_with_type_loc (loc, t, ptrtype);
7640 /* Fold a unary expression of code CODE and type TYPE with operand
7641 OP0. Return the folded expression if folding is successful.
7642 Otherwise, return NULL_TREE. */
7645 fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
7649 enum tree_code_class kind = TREE_CODE_CLASS (code);
7651 gcc_assert (IS_EXPR_CODE_CLASS (kind)
7652 && TREE_CODE_LENGTH (code) == 1);
7657 if (CONVERT_EXPR_CODE_P (code)
7658 || code == FLOAT_EXPR || code == ABS_EXPR)
7660 /* Don't use STRIP_NOPS, because signedness of argument type
7662 STRIP_SIGN_NOPS (arg0);
7666 /* Strip any conversions that don't change the mode. This
7667 is safe for every expression, except for a comparison
7668 expression because its signedness is derived from its
7671 Note that this is done as an internal manipulation within
7672 the constant folder, in order to find the simplest
7673 representation of the arguments so that their form can be
7674 studied. In any cases, the appropriate type conversions
7675 should be put back in the tree that will get out of the
7681 if (TREE_CODE_CLASS (code) == tcc_unary)
7683 if (TREE_CODE (arg0) == COMPOUND_EXPR)
7684 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
7685 fold_build1_loc (loc, code, type,
7686 fold_convert_loc (loc, TREE_TYPE (op0),
7687 TREE_OPERAND (arg0, 1))));
7688 else if (TREE_CODE (arg0) == COND_EXPR)
7690 tree arg01 = TREE_OPERAND (arg0, 1);
7691 tree arg02 = TREE_OPERAND (arg0, 2);
7692 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
7693 arg01 = fold_build1_loc (loc, code, type,
7694 fold_convert_loc (loc,
7695 TREE_TYPE (op0), arg01));
7696 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
7697 arg02 = fold_build1_loc (loc, code, type,
7698 fold_convert_loc (loc,
7699 TREE_TYPE (op0), arg02));
7700 tem = fold_build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg0, 0),
7703 /* If this was a conversion, and all we did was to move into
7704 inside the COND_EXPR, bring it back out. But leave it if
7705 it is a conversion from integer to integer and the
7706 result precision is no wider than a word since such a
7707 conversion is cheap and may be optimized away by combine,
7708 while it couldn't if it were outside the COND_EXPR. Then return
7709 so we don't get into an infinite recursion loop taking the
7710 conversion out and then back in. */
7712 if ((CONVERT_EXPR_CODE_P (code)
7713 || code == NON_LVALUE_EXPR)
7714 && TREE_CODE (tem) == COND_EXPR
7715 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
7716 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
7717 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
7718 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
7719 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
7720 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
7721 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7723 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
7724 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
7725 || flag_syntax_only))
7727 tem = build1 (code, type,
7729 TREE_TYPE (TREE_OPERAND
7730 (TREE_OPERAND (tem, 1), 0)),
7731 TREE_OPERAND (tem, 0),
7732 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
7733 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
7734 SET_EXPR_LOCATION (tem, loc);
7738 else if (COMPARISON_CLASS_P (arg0))
7740 if (TREE_CODE (type) == BOOLEAN_TYPE)
7742 arg0 = copy_node (arg0);
7743 TREE_TYPE (arg0) = type;
7746 else if (TREE_CODE (type) != INTEGER_TYPE)
7747 return fold_build3_loc (loc, COND_EXPR, type, arg0,
7748 fold_build1_loc (loc, code, type,
7750 fold_build1_loc (loc, code, type,
7751 integer_zero_node));
7758 /* Re-association barriers around constants and other re-association
7759 barriers can be removed. */
7760 if (CONSTANT_CLASS_P (op0)
7761 || TREE_CODE (op0) == PAREN_EXPR)
7762 return fold_convert_loc (loc, type, op0);
7767 case FIX_TRUNC_EXPR:
7768 if (TREE_TYPE (op0) == type)
7771 /* If we have (type) (a CMP b) and type is an integral type, return
7772 new expression involving the new type. */
7773 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
7774 return fold_build2_loc (loc, TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
7775 TREE_OPERAND (op0, 1));
7777 /* Handle cases of two conversions in a row. */
7778 if (CONVERT_EXPR_P (op0))
7780 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
7781 tree inter_type = TREE_TYPE (op0);
7782 int inside_int = INTEGRAL_TYPE_P (inside_type);
7783 int inside_ptr = POINTER_TYPE_P (inside_type);
7784 int inside_float = FLOAT_TYPE_P (inside_type);
7785 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
7786 unsigned int inside_prec = TYPE_PRECISION (inside_type);
7787 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
7788 int inter_int = INTEGRAL_TYPE_P (inter_type);
7789 int inter_ptr = POINTER_TYPE_P (inter_type);
7790 int inter_float = FLOAT_TYPE_P (inter_type);
7791 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
7792 unsigned int inter_prec = TYPE_PRECISION (inter_type);
7793 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
7794 int final_int = INTEGRAL_TYPE_P (type);
7795 int final_ptr = POINTER_TYPE_P (type);
7796 int final_float = FLOAT_TYPE_P (type);
7797 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
7798 unsigned int final_prec = TYPE_PRECISION (type);
7799 int final_unsignedp = TYPE_UNSIGNED (type);
7801 /* In addition to the cases of two conversions in a row
7802 handled below, if we are converting something to its own
7803 type via an object of identical or wider precision, neither
7804 conversion is needed. */
7805 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
7806 && (((inter_int || inter_ptr) && final_int)
7807 || (inter_float && final_float))
7808 && inter_prec >= final_prec)
7809 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7811 /* Likewise, if the intermediate and initial types are either both
7812 float or both integer, we don't need the middle conversion if the
7813 former is wider than the latter and doesn't change the signedness
7814 (for integers). Avoid this if the final type is a pointer since
7815 then we sometimes need the middle conversion. Likewise if the
7816 final type has a precision not equal to the size of its mode. */
7817 if (((inter_int && inside_int)
7818 || (inter_float && inside_float)
7819 || (inter_vec && inside_vec))
7820 && inter_prec >= inside_prec
7821 && (inter_float || inter_vec
7822 || inter_unsignedp == inside_unsignedp)
7823 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7824 && TYPE_MODE (type) == TYPE_MODE (inter_type))
7826 && (! final_vec || inter_prec == inside_prec))
7827 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7829 /* If we have a sign-extension of a zero-extended value, we can
7830 replace that by a single zero-extension. */
7831 if (inside_int && inter_int && final_int
7832 && inside_prec < inter_prec && inter_prec < final_prec
7833 && inside_unsignedp && !inter_unsignedp)
7834 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7836 /* Two conversions in a row are not needed unless:
7837 - some conversion is floating-point (overstrict for now), or
7838 - some conversion is a vector (overstrict for now), or
7839 - the intermediate type is narrower than both initial and
7841 - the intermediate type and innermost type differ in signedness,
7842 and the outermost type is wider than the intermediate, or
7843 - the initial type is a pointer type and the precisions of the
7844 intermediate and final types differ, or
7845 - the final type is a pointer type and the precisions of the
7846 initial and intermediate types differ. */
7847 if (! inside_float && ! inter_float && ! final_float
7848 && ! inside_vec && ! inter_vec && ! final_vec
7849 && (inter_prec >= inside_prec || inter_prec >= final_prec)
7850 && ! (inside_int && inter_int
7851 && inter_unsignedp != inside_unsignedp
7852 && inter_prec < final_prec)
7853 && ((inter_unsignedp && inter_prec > inside_prec)
7854 == (final_unsignedp && final_prec > inter_prec))
7855 && ! (inside_ptr && inter_prec != final_prec)
7856 && ! (final_ptr && inside_prec != inter_prec)
7857 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
7858 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
7859 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
7862 /* Handle (T *)&A.B.C for A being of type T and B and C
7863 living at offset zero. This occurs frequently in
7864 C++ upcasting and then accessing the base. */
7865 if (TREE_CODE (op0) == ADDR_EXPR
7866 && POINTER_TYPE_P (type)
7867 && handled_component_p (TREE_OPERAND (op0, 0)))
7869 HOST_WIDE_INT bitsize, bitpos;
7871 enum machine_mode mode;
7872 int unsignedp, volatilep;
7873 tree base = TREE_OPERAND (op0, 0);
7874 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
7875 &mode, &unsignedp, &volatilep, false);
7876 /* If the reference was to a (constant) zero offset, we can use
7877 the address of the base if it has the same base type
7878 as the result type and the pointer type is unqualified. */
7879 if (! offset && bitpos == 0
7880 && (TYPE_MAIN_VARIANT (TREE_TYPE (type))
7881 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
7882 && TYPE_QUALS (type) == TYPE_UNQUALIFIED)
7883 return fold_convert_loc (loc, type,
7884 build_fold_addr_expr_loc (loc, base));
7887 if (TREE_CODE (op0) == MODIFY_EXPR
7888 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
7889 /* Detect assigning a bitfield. */
7890 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
7892 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
7894 /* Don't leave an assignment inside a conversion
7895 unless assigning a bitfield. */
7896 tem = fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 1));
7897 /* First do the assignment, then return converted constant. */
7898 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
7899 TREE_NO_WARNING (tem) = 1;
7900 TREE_USED (tem) = 1;
7901 SET_EXPR_LOCATION (tem, loc);
7905 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
7906 constants (if x has signed type, the sign bit cannot be set
7907 in c). This folds extension into the BIT_AND_EXPR.
7908 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
7909 very likely don't have maximal range for their precision and this
7910 transformation effectively doesn't preserve non-maximal ranges. */
7911 if (TREE_CODE (type) == INTEGER_TYPE
7912 && TREE_CODE (op0) == BIT_AND_EXPR
7913 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
7915 tree and_expr = op0;
7916 tree and0 = TREE_OPERAND (and_expr, 0);
7917 tree and1 = TREE_OPERAND (and_expr, 1);
7920 if (TYPE_UNSIGNED (TREE_TYPE (and_expr))
7921 || (TYPE_PRECISION (type)
7922 <= TYPE_PRECISION (TREE_TYPE (and_expr))))
7924 else if (TYPE_PRECISION (TREE_TYPE (and1))
7925 <= HOST_BITS_PER_WIDE_INT
7926 && host_integerp (and1, 1))
7928 unsigned HOST_WIDE_INT cst;
7930 cst = tree_low_cst (and1, 1);
7931 cst &= (HOST_WIDE_INT) -1
7932 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
7933 change = (cst == 0);
7934 #ifdef LOAD_EXTEND_OP
7936 && !flag_syntax_only
7937 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
7940 tree uns = unsigned_type_for (TREE_TYPE (and0));
7941 and0 = fold_convert_loc (loc, uns, and0);
7942 and1 = fold_convert_loc (loc, uns, and1);
7948 tem = force_fit_type_double (type, tree_to_double_int (and1),
7949 0, TREE_OVERFLOW (and1));
7950 return fold_build2_loc (loc, BIT_AND_EXPR, type,
7951 fold_convert_loc (loc, type, and0), tem);
7955 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
7956 when one of the new casts will fold away. Conservatively we assume
7957 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
7958 if (POINTER_TYPE_P (type)
7959 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
7960 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
7961 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
7962 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
7964 tree arg00 = TREE_OPERAND (arg0, 0);
7965 tree arg01 = TREE_OPERAND (arg0, 1);
7967 return fold_build2_loc (loc,
7968 TREE_CODE (arg0), type,
7969 fold_convert_loc (loc, type, arg00),
7970 fold_convert_loc (loc, sizetype, arg01));
7973 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
7974 of the same precision, and X is an integer type not narrower than
7975 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
7976 if (INTEGRAL_TYPE_P (type)
7977 && TREE_CODE (op0) == BIT_NOT_EXPR
7978 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7979 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
7980 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
7982 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
7983 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
7984 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
7985 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
7986 fold_convert_loc (loc, type, tem));
7989 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
7990 type of X and Y (integer types only). */
7991 if (INTEGRAL_TYPE_P (type)
7992 && TREE_CODE (op0) == MULT_EXPR
7993 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
7994 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
7996 /* Be careful not to introduce new overflows. */
7998 if (TYPE_OVERFLOW_WRAPS (type))
8001 mult_type = unsigned_type_for (type);
8003 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8005 tem = fold_build2_loc (loc, MULT_EXPR, mult_type,
8006 fold_convert_loc (loc, mult_type,
8007 TREE_OPERAND (op0, 0)),
8008 fold_convert_loc (loc, mult_type,
8009 TREE_OPERAND (op0, 1)));
8010 return fold_convert_loc (loc, type, tem);
8014 tem = fold_convert_const (code, type, op0);
8015 return tem ? tem : NULL_TREE;
8017 case ADDR_SPACE_CONVERT_EXPR:
8018 if (integer_zerop (arg0))
8019 return fold_convert_const (code, type, arg0);
8022 case FIXED_CONVERT_EXPR:
8023 tem = fold_convert_const (code, type, arg0);
8024 return tem ? tem : NULL_TREE;
8026 case VIEW_CONVERT_EXPR:
8027 if (TREE_TYPE (op0) == type)
8029 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8030 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8031 type, TREE_OPERAND (op0, 0));
8032 if (TREE_CODE (op0) == MEM_REF)
8033 return fold_build2_loc (loc, MEM_REF, type,
8034 TREE_OPERAND (op0, 0), TREE_OPERAND (op0, 1));
8036 /* For integral conversions with the same precision or pointer
8037 conversions use a NOP_EXPR instead. */
8038 if ((INTEGRAL_TYPE_P (type)
8039 || POINTER_TYPE_P (type))
8040 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8041 || POINTER_TYPE_P (TREE_TYPE (op0)))
8042 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8043 return fold_convert_loc (loc, type, op0);
8045 /* Strip inner integral conversions that do not change the precision. */
8046 if (CONVERT_EXPR_P (op0)
8047 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8048 || POINTER_TYPE_P (TREE_TYPE (op0)))
8049 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8050 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8051 && (TYPE_PRECISION (TREE_TYPE (op0))
8052 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8053 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8054 type, TREE_OPERAND (op0, 0));
8056 return fold_view_convert_expr (type, op0);
8059 tem = fold_negate_expr (loc, arg0);
8061 return fold_convert_loc (loc, type, tem);
8065 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8066 return fold_abs_const (arg0, type);
8067 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8068 return fold_build1_loc (loc, ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8069 /* Convert fabs((double)float) into (double)fabsf(float). */
8070 else if (TREE_CODE (arg0) == NOP_EXPR
8071 && TREE_CODE (type) == REAL_TYPE)
8073 tree targ0 = strip_float_extensions (arg0);
8075 return fold_convert_loc (loc, type,
8076 fold_build1_loc (loc, ABS_EXPR,
8080 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8081 else if (TREE_CODE (arg0) == ABS_EXPR)
8083 else if (tree_expr_nonnegative_p (arg0))
8086 /* Strip sign ops from argument. */
8087 if (TREE_CODE (type) == REAL_TYPE)
8089 tem = fold_strip_sign_ops (arg0);
8091 return fold_build1_loc (loc, ABS_EXPR, type,
8092 fold_convert_loc (loc, type, tem));
8097 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8098 return fold_convert_loc (loc, type, arg0);
8099 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8101 tree itype = TREE_TYPE (type);
8102 tree rpart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 0));
8103 tree ipart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 1));
8104 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart,
8105 negate_expr (ipart));
8107 if (TREE_CODE (arg0) == COMPLEX_CST)
8109 tree itype = TREE_TYPE (type);
8110 tree rpart = fold_convert_loc (loc, itype, TREE_REALPART (arg0));
8111 tree ipart = fold_convert_loc (loc, itype, TREE_IMAGPART (arg0));
8112 return build_complex (type, rpart, negate_expr (ipart));
8114 if (TREE_CODE (arg0) == CONJ_EXPR)
8115 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8119 if (TREE_CODE (arg0) == INTEGER_CST)
8120 return fold_not_const (arg0, type);
8121 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8122 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8123 /* Convert ~ (-A) to A - 1. */
8124 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8125 return fold_build2_loc (loc, MINUS_EXPR, type,
8126 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)),
8127 build_int_cst (type, 1));
8128 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8129 else if (INTEGRAL_TYPE_P (type)
8130 && ((TREE_CODE (arg0) == MINUS_EXPR
8131 && integer_onep (TREE_OPERAND (arg0, 1)))
8132 || (TREE_CODE (arg0) == PLUS_EXPR
8133 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8134 return fold_build1_loc (loc, NEGATE_EXPR, type,
8135 fold_convert_loc (loc, type,
8136 TREE_OPERAND (arg0, 0)));
8137 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8138 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8139 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8140 fold_convert_loc (loc, type,
8141 TREE_OPERAND (arg0, 0)))))
8142 return fold_build2_loc (loc, BIT_XOR_EXPR, type, tem,
8143 fold_convert_loc (loc, type,
8144 TREE_OPERAND (arg0, 1)));
8145 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8146 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8147 fold_convert_loc (loc, type,
8148 TREE_OPERAND (arg0, 1)))))
8149 return fold_build2_loc (loc, BIT_XOR_EXPR, type,
8150 fold_convert_loc (loc, type,
8151 TREE_OPERAND (arg0, 0)), tem);
8152 /* Perform BIT_NOT_EXPR on each element individually. */
8153 else if (TREE_CODE (arg0) == VECTOR_CST)
8155 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8156 int count = TYPE_VECTOR_SUBPARTS (type), i;
8158 for (i = 0; i < count; i++)
8162 elem = TREE_VALUE (elements);
8163 elem = fold_unary_loc (loc, BIT_NOT_EXPR, TREE_TYPE (type), elem);
8164 if (elem == NULL_TREE)
8166 elements = TREE_CHAIN (elements);
8169 elem = build_int_cst (TREE_TYPE (type), -1);
8170 list = tree_cons (NULL_TREE, elem, list);
8173 return build_vector (type, nreverse (list));
8178 case TRUTH_NOT_EXPR:
8179 /* The argument to invert_truthvalue must have Boolean type. */
8180 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8181 arg0 = fold_convert_loc (loc, boolean_type_node, arg0);
8183 /* Note that the operand of this must be an int
8184 and its values must be 0 or 1.
8185 ("true" is a fixed value perhaps depending on the language,
8186 but we don't handle values other than 1 correctly yet.) */
8187 tem = fold_truth_not_expr (loc, arg0);
8190 return fold_convert_loc (loc, type, tem);
8193 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8194 return fold_convert_loc (loc, type, arg0);
8195 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8196 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
8197 TREE_OPERAND (arg0, 1));
8198 if (TREE_CODE (arg0) == COMPLEX_CST)
8199 return fold_convert_loc (loc, type, TREE_REALPART (arg0));
8200 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8202 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8203 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8204 fold_build1_loc (loc, REALPART_EXPR, itype,
8205 TREE_OPERAND (arg0, 0)),
8206 fold_build1_loc (loc, REALPART_EXPR, itype,
8207 TREE_OPERAND (arg0, 1)));
8208 return fold_convert_loc (loc, type, tem);
8210 if (TREE_CODE (arg0) == CONJ_EXPR)
8212 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8213 tem = fold_build1_loc (loc, REALPART_EXPR, itype,
8214 TREE_OPERAND (arg0, 0));
8215 return fold_convert_loc (loc, type, tem);
8217 if (TREE_CODE (arg0) == CALL_EXPR)
8219 tree fn = get_callee_fndecl (arg0);
8220 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8221 switch (DECL_FUNCTION_CODE (fn))
8223 CASE_FLT_FN (BUILT_IN_CEXPI):
8224 fn = mathfn_built_in (type, BUILT_IN_COS);
8226 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8236 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8237 return fold_convert_loc (loc, type, integer_zero_node);
8238 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8239 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 1),
8240 TREE_OPERAND (arg0, 0));
8241 if (TREE_CODE (arg0) == COMPLEX_CST)
8242 return fold_convert_loc (loc, type, TREE_IMAGPART (arg0));
8243 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8245 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8246 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8247 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8248 TREE_OPERAND (arg0, 0)),
8249 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8250 TREE_OPERAND (arg0, 1)));
8251 return fold_convert_loc (loc, type, tem);
8253 if (TREE_CODE (arg0) == CONJ_EXPR)
8255 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8256 tem = fold_build1_loc (loc, IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8257 return fold_convert_loc (loc, type, negate_expr (tem));
8259 if (TREE_CODE (arg0) == CALL_EXPR)
8261 tree fn = get_callee_fndecl (arg0);
8262 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8263 switch (DECL_FUNCTION_CODE (fn))
8265 CASE_FLT_FN (BUILT_IN_CEXPI):
8266 fn = mathfn_built_in (type, BUILT_IN_SIN);
8268 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8278 /* Fold *&X to X if X is an lvalue. */
8279 if (TREE_CODE (op0) == ADDR_EXPR)
8281 tree op00 = TREE_OPERAND (op0, 0);
8282 if ((TREE_CODE (op00) == VAR_DECL
8283 || TREE_CODE (op00) == PARM_DECL
8284 || TREE_CODE (op00) == RESULT_DECL)
8285 && !TREE_READONLY (op00))
8292 } /* switch (code) */
8296 /* If the operation was a conversion do _not_ mark a resulting constant
8297 with TREE_OVERFLOW if the original constant was not. These conversions
8298 have implementation defined behavior and retaining the TREE_OVERFLOW
8299 flag here would confuse later passes such as VRP. */
8301 fold_unary_ignore_overflow_loc (location_t loc, enum tree_code code,
8302 tree type, tree op0)
8304 tree res = fold_unary_loc (loc, code, type, op0);
8306 && TREE_CODE (res) == INTEGER_CST
8307 && TREE_CODE (op0) == INTEGER_CST
8308 && CONVERT_EXPR_CODE_P (code))
8309 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8314 /* Fold a binary expression of code CODE and type TYPE with operands
8315 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8316 Return the folded expression if folding is successful. Otherwise,
8317 return NULL_TREE. */
8320 fold_minmax (location_t loc, enum tree_code code, tree type, tree op0, tree op1)
8322 enum tree_code compl_code;
8324 if (code == MIN_EXPR)
8325 compl_code = MAX_EXPR;
8326 else if (code == MAX_EXPR)
8327 compl_code = MIN_EXPR;
8331 /* MIN (MAX (a, b), b) == b. */
8332 if (TREE_CODE (op0) == compl_code
8333 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8334 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 0));
8336 /* MIN (MAX (b, a), b) == b. */
8337 if (TREE_CODE (op0) == compl_code
8338 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8339 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
8340 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 1));
8342 /* MIN (a, MAX (a, b)) == a. */
8343 if (TREE_CODE (op1) == compl_code
8344 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
8345 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
8346 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 1));
8348 /* MIN (a, MAX (b, a)) == a. */
8349 if (TREE_CODE (op1) == compl_code
8350 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
8351 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
8352 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 0));
8357 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
8358 by changing CODE to reduce the magnitude of constants involved in
8359 ARG0 of the comparison.
8360 Returns a canonicalized comparison tree if a simplification was
8361 possible, otherwise returns NULL_TREE.
8362 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
8363 valid if signed overflow is undefined. */
8366 maybe_canonicalize_comparison_1 (location_t loc, enum tree_code code, tree type,
8367 tree arg0, tree arg1,
8368 bool *strict_overflow_p)
8370 enum tree_code code0 = TREE_CODE (arg0);
8371 tree t, cst0 = NULL_TREE;
8375 /* Match A +- CST code arg1 and CST code arg1. We can change the
8376 first form only if overflow is undefined. */
8377 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8378 /* In principle pointers also have undefined overflow behavior,
8379 but that causes problems elsewhere. */
8380 && !POINTER_TYPE_P (TREE_TYPE (arg0))
8381 && (code0 == MINUS_EXPR
8382 || code0 == PLUS_EXPR)
8383 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
8384 || code0 == INTEGER_CST))
8387 /* Identify the constant in arg0 and its sign. */
8388 if (code0 == INTEGER_CST)
8391 cst0 = TREE_OPERAND (arg0, 1);
8392 sgn0 = tree_int_cst_sgn (cst0);
8394 /* Overflowed constants and zero will cause problems. */
8395 if (integer_zerop (cst0)
8396 || TREE_OVERFLOW (cst0))
8399 /* See if we can reduce the magnitude of the constant in
8400 arg0 by changing the comparison code. */
8401 if (code0 == INTEGER_CST)
8403 /* CST <= arg1 -> CST-1 < arg1. */
8404 if (code == LE_EXPR && sgn0 == 1)
8406 /* -CST < arg1 -> -CST-1 <= arg1. */
8407 else if (code == LT_EXPR && sgn0 == -1)
8409 /* CST > arg1 -> CST-1 >= arg1. */
8410 else if (code == GT_EXPR && sgn0 == 1)
8412 /* -CST >= arg1 -> -CST-1 > arg1. */
8413 else if (code == GE_EXPR && sgn0 == -1)
8417 /* arg1 code' CST' might be more canonical. */
8422 /* A - CST < arg1 -> A - CST-1 <= arg1. */
8424 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8426 /* A + CST > arg1 -> A + CST-1 >= arg1. */
8427 else if (code == GT_EXPR
8428 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8430 /* A + CST <= arg1 -> A + CST-1 < arg1. */
8431 else if (code == LE_EXPR
8432 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
8434 /* A - CST >= arg1 -> A - CST-1 > arg1. */
8435 else if (code == GE_EXPR
8436 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
8440 *strict_overflow_p = true;
8443 /* Now build the constant reduced in magnitude. But not if that
8444 would produce one outside of its types range. */
8445 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
8447 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
8448 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
8450 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
8451 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
8452 /* We cannot swap the comparison here as that would cause us to
8453 endlessly recurse. */
8456 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
8457 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
8458 if (code0 != INTEGER_CST)
8459 t = fold_build2_loc (loc, code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
8461 /* If swapping might yield to a more canonical form, do so. */
8463 return fold_build2_loc (loc, swap_tree_comparison (code), type, arg1, t);
8465 return fold_build2_loc (loc, code, type, t, arg1);
8468 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
8469 overflow further. Try to decrease the magnitude of constants involved
8470 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
8471 and put sole constants at the second argument position.
8472 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
8475 maybe_canonicalize_comparison (location_t loc, enum tree_code code, tree type,
8476 tree arg0, tree arg1)
8479 bool strict_overflow_p;
8480 const char * const warnmsg = G_("assuming signed overflow does not occur "
8481 "when reducing constant in comparison");
8483 /* Try canonicalization by simplifying arg0. */
8484 strict_overflow_p = false;
8485 t = maybe_canonicalize_comparison_1 (loc, code, type, arg0, arg1,
8486 &strict_overflow_p);
8489 if (strict_overflow_p)
8490 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8494 /* Try canonicalization by simplifying arg1 using the swapped
8496 code = swap_tree_comparison (code);
8497 strict_overflow_p = false;
8498 t = maybe_canonicalize_comparison_1 (loc, code, type, arg1, arg0,
8499 &strict_overflow_p);
8500 if (t && strict_overflow_p)
8501 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
8505 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
8506 space. This is used to avoid issuing overflow warnings for
8507 expressions like &p->x which can not wrap. */
8510 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
8512 unsigned HOST_WIDE_INT offset_low, total_low;
8513 HOST_WIDE_INT size, offset_high, total_high;
8515 if (!POINTER_TYPE_P (TREE_TYPE (base)))
8521 if (offset == NULL_TREE)
8526 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
8530 offset_low = TREE_INT_CST_LOW (offset);
8531 offset_high = TREE_INT_CST_HIGH (offset);
8534 if (add_double_with_sign (offset_low, offset_high,
8535 bitpos / BITS_PER_UNIT, 0,
8536 &total_low, &total_high,
8540 if (total_high != 0)
8543 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
8547 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
8549 if (TREE_CODE (base) == ADDR_EXPR)
8551 HOST_WIDE_INT base_size;
8553 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
8554 if (base_size > 0 && size < base_size)
8558 return total_low > (unsigned HOST_WIDE_INT) size;
8561 /* Subroutine of fold_binary. This routine performs all of the
8562 transformations that are common to the equality/inequality
8563 operators (EQ_EXPR and NE_EXPR) and the ordering operators
8564 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
8565 fold_binary should call fold_binary. Fold a comparison with
8566 tree code CODE and type TYPE with operands OP0 and OP1. Return
8567 the folded comparison or NULL_TREE. */
8570 fold_comparison (location_t loc, enum tree_code code, tree type,
8573 tree arg0, arg1, tem;
8578 STRIP_SIGN_NOPS (arg0);
8579 STRIP_SIGN_NOPS (arg1);
8581 tem = fold_relational_const (code, type, arg0, arg1);
8582 if (tem != NULL_TREE)
8585 /* If one arg is a real or integer constant, put it last. */
8586 if (tree_swap_operands_p (arg0, arg1, true))
8587 return fold_build2_loc (loc, swap_tree_comparison (code), type, op1, op0);
8589 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
8590 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8591 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8592 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
8593 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
8594 && (TREE_CODE (arg1) == INTEGER_CST
8595 && !TREE_OVERFLOW (arg1)))
8597 tree const1 = TREE_OPERAND (arg0, 1);
8599 tree variable = TREE_OPERAND (arg0, 0);
8602 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
8604 lhs = fold_build2_loc (loc, lhs_add ? PLUS_EXPR : MINUS_EXPR,
8605 TREE_TYPE (arg1), const2, const1);
8607 /* If the constant operation overflowed this can be
8608 simplified as a comparison against INT_MAX/INT_MIN. */
8609 if (TREE_CODE (lhs) == INTEGER_CST
8610 && TREE_OVERFLOW (lhs))
8612 int const1_sgn = tree_int_cst_sgn (const1);
8613 enum tree_code code2 = code;
8615 /* Get the sign of the constant on the lhs if the
8616 operation were VARIABLE + CONST1. */
8617 if (TREE_CODE (arg0) == MINUS_EXPR)
8618 const1_sgn = -const1_sgn;
8620 /* The sign of the constant determines if we overflowed
8621 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
8622 Canonicalize to the INT_MIN overflow by swapping the comparison
8624 if (const1_sgn == -1)
8625 code2 = swap_tree_comparison (code);
8627 /* We now can look at the canonicalized case
8628 VARIABLE + 1 CODE2 INT_MIN
8629 and decide on the result. */
8630 if (code2 == LT_EXPR
8632 || code2 == EQ_EXPR)
8633 return omit_one_operand_loc (loc, type, boolean_false_node, variable);
8634 else if (code2 == NE_EXPR
8636 || code2 == GT_EXPR)
8637 return omit_one_operand_loc (loc, type, boolean_true_node, variable);
8640 if (TREE_CODE (lhs) == TREE_CODE (arg1)
8641 && (TREE_CODE (lhs) != INTEGER_CST
8642 || !TREE_OVERFLOW (lhs)))
8644 fold_overflow_warning ("assuming signed overflow does not occur "
8645 "when changing X +- C1 cmp C2 to "
8647 WARN_STRICT_OVERFLOW_COMPARISON);
8648 return fold_build2_loc (loc, code, type, variable, lhs);
8652 /* For comparisons of pointers we can decompose it to a compile time
8653 comparison of the base objects and the offsets into the object.
8654 This requires at least one operand being an ADDR_EXPR or a
8655 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
8656 if (POINTER_TYPE_P (TREE_TYPE (arg0))
8657 && (TREE_CODE (arg0) == ADDR_EXPR
8658 || TREE_CODE (arg1) == ADDR_EXPR
8659 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
8660 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
8662 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
8663 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
8664 enum machine_mode mode;
8665 int volatilep, unsignedp;
8666 bool indirect_base0 = false, indirect_base1 = false;
8668 /* Get base and offset for the access. Strip ADDR_EXPR for
8669 get_inner_reference, but put it back by stripping INDIRECT_REF
8670 off the base object if possible. indirect_baseN will be true
8671 if baseN is not an address but refers to the object itself. */
8673 if (TREE_CODE (arg0) == ADDR_EXPR)
8675 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
8676 &bitsize, &bitpos0, &offset0, &mode,
8677 &unsignedp, &volatilep, false);
8678 if (TREE_CODE (base0) == INDIRECT_REF)
8679 base0 = TREE_OPERAND (base0, 0);
8681 indirect_base0 = true;
8683 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
8685 base0 = TREE_OPERAND (arg0, 0);
8686 STRIP_SIGN_NOPS (base0);
8687 if (TREE_CODE (base0) == ADDR_EXPR)
8689 base0 = TREE_OPERAND (base0, 0);
8690 indirect_base0 = true;
8692 offset0 = TREE_OPERAND (arg0, 1);
8696 if (TREE_CODE (arg1) == ADDR_EXPR)
8698 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
8699 &bitsize, &bitpos1, &offset1, &mode,
8700 &unsignedp, &volatilep, false);
8701 if (TREE_CODE (base1) == INDIRECT_REF)
8702 base1 = TREE_OPERAND (base1, 0);
8704 indirect_base1 = true;
8706 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
8708 base1 = TREE_OPERAND (arg1, 0);
8709 STRIP_SIGN_NOPS (base1);
8710 if (TREE_CODE (base1) == ADDR_EXPR)
8712 base1 = TREE_OPERAND (base1, 0);
8713 indirect_base1 = true;
8715 offset1 = TREE_OPERAND (arg1, 1);
8718 /* A local variable can never be pointed to by
8719 the default SSA name of an incoming parameter. */
8720 if ((TREE_CODE (arg0) == ADDR_EXPR
8722 && TREE_CODE (base0) == VAR_DECL
8723 && auto_var_in_fn_p (base0, current_function_decl)
8725 && TREE_CODE (base1) == SSA_NAME
8726 && TREE_CODE (SSA_NAME_VAR (base1)) == PARM_DECL
8727 && SSA_NAME_IS_DEFAULT_DEF (base1))
8728 || (TREE_CODE (arg1) == ADDR_EXPR
8730 && TREE_CODE (base1) == VAR_DECL
8731 && auto_var_in_fn_p (base1, current_function_decl)
8733 && TREE_CODE (base0) == SSA_NAME
8734 && TREE_CODE (SSA_NAME_VAR (base0)) == PARM_DECL
8735 && SSA_NAME_IS_DEFAULT_DEF (base0)))
8737 if (code == NE_EXPR)
8738 return constant_boolean_node (1, type);
8739 else if (code == EQ_EXPR)
8740 return constant_boolean_node (0, type);
8742 /* If we have equivalent bases we might be able to simplify. */
8743 else if (indirect_base0 == indirect_base1
8744 && operand_equal_p (base0, base1, 0))
8746 /* We can fold this expression to a constant if the non-constant
8747 offset parts are equal. */
8748 if ((offset0 == offset1
8749 || (offset0 && offset1
8750 && operand_equal_p (offset0, offset1, 0)))
8753 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8758 && bitpos0 != bitpos1
8759 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8760 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8761 fold_overflow_warning (("assuming pointer wraparound does not "
8762 "occur when comparing P +- C1 with "
8764 WARN_STRICT_OVERFLOW_CONDITIONAL);
8769 return constant_boolean_node (bitpos0 == bitpos1, type);
8771 return constant_boolean_node (bitpos0 != bitpos1, type);
8773 return constant_boolean_node (bitpos0 < bitpos1, type);
8775 return constant_boolean_node (bitpos0 <= bitpos1, type);
8777 return constant_boolean_node (bitpos0 >= bitpos1, type);
8779 return constant_boolean_node (bitpos0 > bitpos1, type);
8783 /* We can simplify the comparison to a comparison of the variable
8784 offset parts if the constant offset parts are equal.
8785 Be careful to use signed size type here because otherwise we
8786 mess with array offsets in the wrong way. This is possible
8787 because pointer arithmetic is restricted to retain within an
8788 object and overflow on pointer differences is undefined as of
8789 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
8790 else if (bitpos0 == bitpos1
8791 && ((code == EQ_EXPR || code == NE_EXPR)
8792 || POINTER_TYPE_OVERFLOW_UNDEFINED))
8794 /* By converting to signed size type we cover middle-end pointer
8795 arithmetic which operates on unsigned pointer types of size
8796 type size and ARRAY_REF offsets which are properly sign or
8797 zero extended from their type in case it is narrower than
8799 if (offset0 == NULL_TREE)
8800 offset0 = build_int_cst (ssizetype, 0);
8802 offset0 = fold_convert_loc (loc, ssizetype, offset0);
8803 if (offset1 == NULL_TREE)
8804 offset1 = build_int_cst (ssizetype, 0);
8806 offset1 = fold_convert_loc (loc, ssizetype, offset1);
8810 && (pointer_may_wrap_p (base0, offset0, bitpos0)
8811 || pointer_may_wrap_p (base1, offset1, bitpos1)))
8812 fold_overflow_warning (("assuming pointer wraparound does not "
8813 "occur when comparing P +- C1 with "
8815 WARN_STRICT_OVERFLOW_COMPARISON);
8817 return fold_build2_loc (loc, code, type, offset0, offset1);
8820 /* For non-equal bases we can simplify if they are addresses
8821 of local binding decls or constants. */
8822 else if (indirect_base0 && indirect_base1
8823 /* We know that !operand_equal_p (base0, base1, 0)
8824 because the if condition was false. But make
8825 sure two decls are not the same. */
8827 && TREE_CODE (arg0) == ADDR_EXPR
8828 && TREE_CODE (arg1) == ADDR_EXPR
8829 && (((TREE_CODE (base0) == VAR_DECL
8830 || TREE_CODE (base0) == PARM_DECL)
8831 && (targetm.binds_local_p (base0)
8832 || CONSTANT_CLASS_P (base1)))
8833 || CONSTANT_CLASS_P (base0))
8834 && (((TREE_CODE (base1) == VAR_DECL
8835 || TREE_CODE (base1) == PARM_DECL)
8836 && (targetm.binds_local_p (base1)
8837 || CONSTANT_CLASS_P (base0)))
8838 || CONSTANT_CLASS_P (base1)))
8840 if (code == EQ_EXPR)
8841 return omit_two_operands_loc (loc, type, boolean_false_node,
8843 else if (code == NE_EXPR)
8844 return omit_two_operands_loc (loc, type, boolean_true_node,
8847 /* For equal offsets we can simplify to a comparison of the
8849 else if (bitpos0 == bitpos1
8851 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
8853 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
8854 && ((offset0 == offset1)
8855 || (offset0 && offset1
8856 && operand_equal_p (offset0, offset1, 0))))
8859 base0 = build_fold_addr_expr_loc (loc, base0);
8861 base1 = build_fold_addr_expr_loc (loc, base1);
8862 return fold_build2_loc (loc, code, type, base0, base1);
8866 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
8867 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
8868 the resulting offset is smaller in absolute value than the
8870 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8871 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8872 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8873 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8874 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
8875 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
8876 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
8878 tree const1 = TREE_OPERAND (arg0, 1);
8879 tree const2 = TREE_OPERAND (arg1, 1);
8880 tree variable1 = TREE_OPERAND (arg0, 0);
8881 tree variable2 = TREE_OPERAND (arg1, 0);
8883 const char * const warnmsg = G_("assuming signed overflow does not "
8884 "occur when combining constants around "
8887 /* Put the constant on the side where it doesn't overflow and is
8888 of lower absolute value than before. */
8889 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8890 ? MINUS_EXPR : PLUS_EXPR,
8892 if (!TREE_OVERFLOW (cst)
8893 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
8895 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8896 return fold_build2_loc (loc, code, type,
8898 fold_build2_loc (loc,
8899 TREE_CODE (arg1), TREE_TYPE (arg1),
8903 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
8904 ? MINUS_EXPR : PLUS_EXPR,
8906 if (!TREE_OVERFLOW (cst)
8907 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
8909 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
8910 return fold_build2_loc (loc, code, type,
8911 fold_build2_loc (loc, TREE_CODE (arg0), TREE_TYPE (arg0),
8917 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
8918 signed arithmetic case. That form is created by the compiler
8919 often enough for folding it to be of value. One example is in
8920 computing loop trip counts after Operator Strength Reduction. */
8921 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
8922 && TREE_CODE (arg0) == MULT_EXPR
8923 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8924 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
8925 && integer_zerop (arg1))
8927 tree const1 = TREE_OPERAND (arg0, 1);
8928 tree const2 = arg1; /* zero */
8929 tree variable1 = TREE_OPERAND (arg0, 0);
8930 enum tree_code cmp_code = code;
8932 /* Handle unfolded multiplication by zero. */
8933 if (integer_zerop (const1))
8934 return fold_build2_loc (loc, cmp_code, type, const1, const2);
8936 fold_overflow_warning (("assuming signed overflow does not occur when "
8937 "eliminating multiplication in comparison "
8939 WARN_STRICT_OVERFLOW_COMPARISON);
8941 /* If const1 is negative we swap the sense of the comparison. */
8942 if (tree_int_cst_sgn (const1) < 0)
8943 cmp_code = swap_tree_comparison (cmp_code);
8945 return fold_build2_loc (loc, cmp_code, type, variable1, const2);
8948 tem = maybe_canonicalize_comparison (loc, code, type, op0, op1);
8952 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
8954 tree targ0 = strip_float_extensions (arg0);
8955 tree targ1 = strip_float_extensions (arg1);
8956 tree newtype = TREE_TYPE (targ0);
8958 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
8959 newtype = TREE_TYPE (targ1);
8961 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
8962 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
8963 return fold_build2_loc (loc, code, type,
8964 fold_convert_loc (loc, newtype, targ0),
8965 fold_convert_loc (loc, newtype, targ1));
8967 /* (-a) CMP (-b) -> b CMP a */
8968 if (TREE_CODE (arg0) == NEGATE_EXPR
8969 && TREE_CODE (arg1) == NEGATE_EXPR)
8970 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg1, 0),
8971 TREE_OPERAND (arg0, 0));
8973 if (TREE_CODE (arg1) == REAL_CST)
8975 REAL_VALUE_TYPE cst;
8976 cst = TREE_REAL_CST (arg1);
8978 /* (-a) CMP CST -> a swap(CMP) (-CST) */
8979 if (TREE_CODE (arg0) == NEGATE_EXPR)
8980 return fold_build2_loc (loc, swap_tree_comparison (code), type,
8981 TREE_OPERAND (arg0, 0),
8982 build_real (TREE_TYPE (arg1),
8983 real_value_negate (&cst)));
8985 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
8986 /* a CMP (-0) -> a CMP 0 */
8987 if (REAL_VALUE_MINUS_ZERO (cst))
8988 return fold_build2_loc (loc, code, type, arg0,
8989 build_real (TREE_TYPE (arg1), dconst0));
8991 /* x != NaN is always true, other ops are always false. */
8992 if (REAL_VALUE_ISNAN (cst)
8993 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
8995 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
8996 return omit_one_operand_loc (loc, type, tem, arg0);
8999 /* Fold comparisons against infinity. */
9000 if (REAL_VALUE_ISINF (cst)
9001 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
9003 tem = fold_inf_compare (loc, code, type, arg0, arg1);
9004 if (tem != NULL_TREE)
9009 /* If this is a comparison of a real constant with a PLUS_EXPR
9010 or a MINUS_EXPR of a real constant, we can convert it into a
9011 comparison with a revised real constant as long as no overflow
9012 occurs when unsafe_math_optimizations are enabled. */
9013 if (flag_unsafe_math_optimizations
9014 && TREE_CODE (arg1) == REAL_CST
9015 && (TREE_CODE (arg0) == PLUS_EXPR
9016 || TREE_CODE (arg0) == MINUS_EXPR)
9017 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9018 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9019 ? MINUS_EXPR : PLUS_EXPR,
9020 arg1, TREE_OPERAND (arg0, 1)))
9021 && !TREE_OVERFLOW (tem))
9022 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
9024 /* Likewise, we can simplify a comparison of a real constant with
9025 a MINUS_EXPR whose first operand is also a real constant, i.e.
9026 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9027 floating-point types only if -fassociative-math is set. */
9028 if (flag_associative_math
9029 && TREE_CODE (arg1) == REAL_CST
9030 && TREE_CODE (arg0) == MINUS_EXPR
9031 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9032 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9034 && !TREE_OVERFLOW (tem))
9035 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9036 TREE_OPERAND (arg0, 1), tem);
9038 /* Fold comparisons against built-in math functions. */
9039 if (TREE_CODE (arg1) == REAL_CST
9040 && flag_unsafe_math_optimizations
9041 && ! flag_errno_math)
9043 enum built_in_function fcode = builtin_mathfn_code (arg0);
9045 if (fcode != END_BUILTINS)
9047 tem = fold_mathfn_compare (loc, fcode, code, type, arg0, arg1);
9048 if (tem != NULL_TREE)
9054 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9055 && CONVERT_EXPR_P (arg0))
9057 /* If we are widening one operand of an integer comparison,
9058 see if the other operand is similarly being widened. Perhaps we
9059 can do the comparison in the narrower type. */
9060 tem = fold_widened_comparison (loc, code, type, arg0, arg1);
9064 /* Or if we are changing signedness. */
9065 tem = fold_sign_changed_comparison (loc, code, type, arg0, arg1);
9070 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9071 constant, we can simplify it. */
9072 if (TREE_CODE (arg1) == INTEGER_CST
9073 && (TREE_CODE (arg0) == MIN_EXPR
9074 || TREE_CODE (arg0) == MAX_EXPR)
9075 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9077 tem = optimize_minmax_comparison (loc, code, type, op0, op1);
9082 /* Simplify comparison of something with itself. (For IEEE
9083 floating-point, we can only do some of these simplifications.) */
9084 if (operand_equal_p (arg0, arg1, 0))
9089 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9090 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9091 return constant_boolean_node (1, type);
9096 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9097 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9098 return constant_boolean_node (1, type);
9099 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg1);
9102 /* For NE, we can only do this simplification if integer
9103 or we don't honor IEEE floating point NaNs. */
9104 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9105 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9107 /* ... fall through ... */
9110 return constant_boolean_node (0, type);
9116 /* If we are comparing an expression that just has comparisons
9117 of two integer values, arithmetic expressions of those comparisons,
9118 and constants, we can simplify it. There are only three cases
9119 to check: the two values can either be equal, the first can be
9120 greater, or the second can be greater. Fold the expression for
9121 those three values. Since each value must be 0 or 1, we have
9122 eight possibilities, each of which corresponds to the constant 0
9123 or 1 or one of the six possible comparisons.
9125 This handles common cases like (a > b) == 0 but also handles
9126 expressions like ((x > y) - (y > x)) > 0, which supposedly
9127 occur in macroized code. */
9129 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9131 tree cval1 = 0, cval2 = 0;
9134 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9135 /* Don't handle degenerate cases here; they should already
9136 have been handled anyway. */
9137 && cval1 != 0 && cval2 != 0
9138 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9139 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9140 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9141 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9142 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9143 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9144 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9146 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9147 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9149 /* We can't just pass T to eval_subst in case cval1 or cval2
9150 was the same as ARG1. */
9153 = fold_build2_loc (loc, code, type,
9154 eval_subst (loc, arg0, cval1, maxval,
9158 = fold_build2_loc (loc, code, type,
9159 eval_subst (loc, arg0, cval1, maxval,
9163 = fold_build2_loc (loc, code, type,
9164 eval_subst (loc, arg0, cval1, minval,
9168 /* All three of these results should be 0 or 1. Confirm they are.
9169 Then use those values to select the proper code to use. */
9171 if (TREE_CODE (high_result) == INTEGER_CST
9172 && TREE_CODE (equal_result) == INTEGER_CST
9173 && TREE_CODE (low_result) == INTEGER_CST)
9175 /* Make a 3-bit mask with the high-order bit being the
9176 value for `>', the next for '=', and the low for '<'. */
9177 switch ((integer_onep (high_result) * 4)
9178 + (integer_onep (equal_result) * 2)
9179 + integer_onep (low_result))
9183 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
9204 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
9209 tem = save_expr (build2 (code, type, cval1, cval2));
9210 SET_EXPR_LOCATION (tem, loc);
9213 return fold_build2_loc (loc, code, type, cval1, cval2);
9218 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9219 into a single range test. */
9220 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9221 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9222 && TREE_CODE (arg1) == INTEGER_CST
9223 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9224 && !integer_zerop (TREE_OPERAND (arg0, 1))
9225 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9226 && !TREE_OVERFLOW (arg1))
9228 tem = fold_div_compare (loc, code, type, arg0, arg1);
9229 if (tem != NULL_TREE)
9233 /* Fold ~X op ~Y as Y op X. */
9234 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9235 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9237 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9238 return fold_build2_loc (loc, code, type,
9239 fold_convert_loc (loc, cmp_type,
9240 TREE_OPERAND (arg1, 0)),
9241 TREE_OPERAND (arg0, 0));
9244 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9245 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9246 && TREE_CODE (arg1) == INTEGER_CST)
9248 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9249 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9250 TREE_OPERAND (arg0, 0),
9251 fold_build1_loc (loc, BIT_NOT_EXPR, cmp_type,
9252 fold_convert_loc (loc, cmp_type, arg1)));
9259 /* Subroutine of fold_binary. Optimize complex multiplications of the
9260 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9261 argument EXPR represents the expression "z" of type TYPE. */
9264 fold_mult_zconjz (location_t loc, tree type, tree expr)
9266 tree itype = TREE_TYPE (type);
9267 tree rpart, ipart, tem;
9269 if (TREE_CODE (expr) == COMPLEX_EXPR)
9271 rpart = TREE_OPERAND (expr, 0);
9272 ipart = TREE_OPERAND (expr, 1);
9274 else if (TREE_CODE (expr) == COMPLEX_CST)
9276 rpart = TREE_REALPART (expr);
9277 ipart = TREE_IMAGPART (expr);
9281 expr = save_expr (expr);
9282 rpart = fold_build1_loc (loc, REALPART_EXPR, itype, expr);
9283 ipart = fold_build1_loc (loc, IMAGPART_EXPR, itype, expr);
9286 rpart = save_expr (rpart);
9287 ipart = save_expr (ipart);
9288 tem = fold_build2_loc (loc, PLUS_EXPR, itype,
9289 fold_build2_loc (loc, MULT_EXPR, itype, rpart, rpart),
9290 fold_build2_loc (loc, MULT_EXPR, itype, ipart, ipart));
9291 return fold_build2_loc (loc, COMPLEX_EXPR, type, tem,
9292 fold_convert_loc (loc, itype, integer_zero_node));
9296 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9297 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9298 guarantees that P and N have the same least significant log2(M) bits.
9299 N is not otherwise constrained. In particular, N is not normalized to
9300 0 <= N < M as is common. In general, the precise value of P is unknown.
9301 M is chosen as large as possible such that constant N can be determined.
9303 Returns M and sets *RESIDUE to N.
9305 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9306 account. This is not always possible due to PR 35705.
9309 static unsigned HOST_WIDE_INT
9310 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9311 bool allow_func_align)
9313 enum tree_code code;
9317 code = TREE_CODE (expr);
9318 if (code == ADDR_EXPR)
9320 expr = TREE_OPERAND (expr, 0);
9321 if (handled_component_p (expr))
9323 HOST_WIDE_INT bitsize, bitpos;
9325 enum machine_mode mode;
9326 int unsignedp, volatilep;
9328 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9329 &mode, &unsignedp, &volatilep, false);
9330 *residue = bitpos / BITS_PER_UNIT;
9333 if (TREE_CODE (offset) == INTEGER_CST)
9334 *residue += TREE_INT_CST_LOW (offset);
9336 /* We don't handle more complicated offset expressions. */
9342 && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL))
9343 return DECL_ALIGN_UNIT (expr);
9345 else if (code == POINTER_PLUS_EXPR)
9348 unsigned HOST_WIDE_INT modulus;
9349 enum tree_code inner_code;
9351 op0 = TREE_OPERAND (expr, 0);
9353 modulus = get_pointer_modulus_and_residue (op0, residue,
9356 op1 = TREE_OPERAND (expr, 1);
9358 inner_code = TREE_CODE (op1);
9359 if (inner_code == INTEGER_CST)
9361 *residue += TREE_INT_CST_LOW (op1);
9364 else if (inner_code == MULT_EXPR)
9366 op1 = TREE_OPERAND (op1, 1);
9367 if (TREE_CODE (op1) == INTEGER_CST)
9369 unsigned HOST_WIDE_INT align;
9371 /* Compute the greatest power-of-2 divisor of op1. */
9372 align = TREE_INT_CST_LOW (op1);
9375 /* If align is non-zero and less than *modulus, replace
9376 *modulus with align., If align is 0, then either op1 is 0
9377 or the greatest power-of-2 divisor of op1 doesn't fit in an
9378 unsigned HOST_WIDE_INT. In either case, no additional
9379 constraint is imposed. */
9381 modulus = MIN (modulus, align);
9388 /* If we get here, we were unable to determine anything useful about the
9394 /* Fold a binary expression of code CODE and type TYPE with operands
9395 OP0 and OP1. LOC is the location of the resulting expression.
9396 Return the folded expression if folding is successful. Otherwise,
9397 return NULL_TREE. */
9400 fold_binary_loc (location_t loc,
9401 enum tree_code code, tree type, tree op0, tree op1)
9403 enum tree_code_class kind = TREE_CODE_CLASS (code);
9404 tree arg0, arg1, tem;
9405 tree t1 = NULL_TREE;
9406 bool strict_overflow_p;
9408 gcc_assert (IS_EXPR_CODE_CLASS (kind)
9409 && TREE_CODE_LENGTH (code) == 2
9411 && op1 != NULL_TREE);
9416 /* Strip any conversions that don't change the mode. This is
9417 safe for every expression, except for a comparison expression
9418 because its signedness is derived from its operands. So, in
9419 the latter case, only strip conversions that don't change the
9420 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
9423 Note that this is done as an internal manipulation within the
9424 constant folder, in order to find the simplest representation
9425 of the arguments so that their form can be studied. In any
9426 cases, the appropriate type conversions should be put back in
9427 the tree that will get out of the constant folder. */
9429 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
9431 STRIP_SIGN_NOPS (arg0);
9432 STRIP_SIGN_NOPS (arg1);
9440 /* Note that TREE_CONSTANT isn't enough: static var addresses are
9441 constant but we can't do arithmetic on them. */
9442 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9443 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
9444 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
9445 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
9446 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
9447 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
9449 if (kind == tcc_binary)
9451 /* Make sure type and arg0 have the same saturating flag. */
9452 gcc_assert (TYPE_SATURATING (type)
9453 == TYPE_SATURATING (TREE_TYPE (arg0)));
9454 tem = const_binop (code, arg0, arg1);
9456 else if (kind == tcc_comparison)
9457 tem = fold_relational_const (code, type, arg0, arg1);
9461 if (tem != NULL_TREE)
9463 if (TREE_TYPE (tem) != type)
9464 tem = fold_convert_loc (loc, type, tem);
9469 /* If this is a commutative operation, and ARG0 is a constant, move it
9470 to ARG1 to reduce the number of tests below. */
9471 if (commutative_tree_code (code)
9472 && tree_swap_operands_p (arg0, arg1, true))
9473 return fold_build2_loc (loc, code, type, op1, op0);
9475 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
9477 First check for cases where an arithmetic operation is applied to a
9478 compound, conditional, or comparison operation. Push the arithmetic
9479 operation inside the compound or conditional to see if any folding
9480 can then be done. Convert comparison to conditional for this purpose.
9481 The also optimizes non-constant cases that used to be done in
9484 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
9485 one of the operands is a comparison and the other is a comparison, a
9486 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
9487 code below would make the expression more complex. Change it to a
9488 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
9489 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
9491 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
9492 || code == EQ_EXPR || code == NE_EXPR)
9493 && ((truth_value_p (TREE_CODE (arg0))
9494 && (truth_value_p (TREE_CODE (arg1))
9495 || (TREE_CODE (arg1) == BIT_AND_EXPR
9496 && integer_onep (TREE_OPERAND (arg1, 1)))))
9497 || (truth_value_p (TREE_CODE (arg1))
9498 && (truth_value_p (TREE_CODE (arg0))
9499 || (TREE_CODE (arg0) == BIT_AND_EXPR
9500 && integer_onep (TREE_OPERAND (arg0, 1)))))))
9502 tem = fold_build2_loc (loc, code == BIT_AND_EXPR ? TRUTH_AND_EXPR
9503 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
9506 fold_convert_loc (loc, boolean_type_node, arg0),
9507 fold_convert_loc (loc, boolean_type_node, arg1));
9509 if (code == EQ_EXPR)
9510 tem = invert_truthvalue_loc (loc, tem);
9512 return fold_convert_loc (loc, type, tem);
9515 if (TREE_CODE_CLASS (code) == tcc_binary
9516 || TREE_CODE_CLASS (code) == tcc_comparison)
9518 if (TREE_CODE (arg0) == COMPOUND_EXPR)
9520 tem = fold_build2_loc (loc, code, type,
9521 fold_convert_loc (loc, TREE_TYPE (op0),
9522 TREE_OPERAND (arg0, 1)), op1);
9523 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), tem);
9524 goto fold_binary_exit;
9526 if (TREE_CODE (arg1) == COMPOUND_EXPR
9527 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
9529 tem = fold_build2_loc (loc, code, type, op0,
9530 fold_convert_loc (loc, TREE_TYPE (op1),
9531 TREE_OPERAND (arg1, 1)));
9532 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), tem);
9533 goto fold_binary_exit;
9536 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
9538 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9540 /*cond_first_p=*/1);
9541 if (tem != NULL_TREE)
9545 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
9547 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
9549 /*cond_first_p=*/0);
9550 if (tem != NULL_TREE)
9558 /* MEM[&MEM[p, CST1], CST2] -> MEM[p, CST1 + CST2]. */
9559 if (TREE_CODE (arg0) == ADDR_EXPR
9560 && TREE_CODE (TREE_OPERAND (arg0, 0)) == MEM_REF)
9562 tree iref = TREE_OPERAND (arg0, 0);
9563 return fold_build2 (MEM_REF, type,
9564 TREE_OPERAND (iref, 0),
9565 int_const_binop (PLUS_EXPR, arg1,
9566 TREE_OPERAND (iref, 1), 0));
9569 /* MEM[&a.b, CST2] -> MEM[&a, offsetof (a, b) + CST2]. */
9570 if (TREE_CODE (arg0) == ADDR_EXPR
9571 && handled_component_p (TREE_OPERAND (arg0, 0)))
9574 HOST_WIDE_INT coffset;
9575 base = get_addr_base_and_unit_offset (TREE_OPERAND (arg0, 0),
9579 return fold_build2 (MEM_REF, type,
9580 build_fold_addr_expr (base),
9581 int_const_binop (PLUS_EXPR, arg1,
9582 size_int (coffset), 0));
9587 case POINTER_PLUS_EXPR:
9588 /* 0 +p index -> (type)index */
9589 if (integer_zerop (arg0))
9590 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9592 /* PTR +p 0 -> PTR */
9593 if (integer_zerop (arg1))
9594 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9596 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
9597 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
9598 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9599 return fold_convert_loc (loc, type,
9600 fold_build2_loc (loc, PLUS_EXPR, sizetype,
9601 fold_convert_loc (loc, sizetype,
9603 fold_convert_loc (loc, sizetype,
9606 /* index +p PTR -> PTR +p index */
9607 if (POINTER_TYPE_P (TREE_TYPE (arg1))
9608 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
9609 return fold_build2_loc (loc, POINTER_PLUS_EXPR, type,
9610 fold_convert_loc (loc, type, arg1),
9611 fold_convert_loc (loc, sizetype, arg0));
9613 /* (PTR +p B) +p A -> PTR +p (B + A) */
9614 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9617 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
9618 tree arg00 = TREE_OPERAND (arg0, 0);
9619 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
9620 arg01, fold_convert_loc (loc, sizetype, arg1));
9621 return fold_convert_loc (loc, type,
9622 fold_build2_loc (loc, POINTER_PLUS_EXPR,
9627 /* PTR_CST +p CST -> CST1 */
9628 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
9629 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
9630 fold_convert_loc (loc, type, arg1));
9632 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
9633 of the array. Loop optimizer sometimes produce this type of
9635 if (TREE_CODE (arg0) == ADDR_EXPR)
9637 tem = try_move_mult_to_index (loc, arg0,
9638 fold_convert_loc (loc, sizetype, arg1));
9640 return fold_convert_loc (loc, type, tem);
9646 /* A + (-B) -> A - B */
9647 if (TREE_CODE (arg1) == NEGATE_EXPR)
9648 return fold_build2_loc (loc, MINUS_EXPR, type,
9649 fold_convert_loc (loc, type, arg0),
9650 fold_convert_loc (loc, type,
9651 TREE_OPERAND (arg1, 0)));
9652 /* (-A) + B -> B - A */
9653 if (TREE_CODE (arg0) == NEGATE_EXPR
9654 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
9655 return fold_build2_loc (loc, MINUS_EXPR, type,
9656 fold_convert_loc (loc, type, arg1),
9657 fold_convert_loc (loc, type,
9658 TREE_OPERAND (arg0, 0)));
9660 if (INTEGRAL_TYPE_P (type))
9662 /* Convert ~A + 1 to -A. */
9663 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9664 && integer_onep (arg1))
9665 return fold_build1_loc (loc, NEGATE_EXPR, type,
9666 fold_convert_loc (loc, type,
9667 TREE_OPERAND (arg0, 0)));
9670 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9671 && !TYPE_OVERFLOW_TRAPS (type))
9673 tree tem = TREE_OPERAND (arg0, 0);
9676 if (operand_equal_p (tem, arg1, 0))
9678 t1 = build_int_cst_type (type, -1);
9679 return omit_one_operand_loc (loc, type, t1, arg1);
9684 if (TREE_CODE (arg1) == BIT_NOT_EXPR
9685 && !TYPE_OVERFLOW_TRAPS (type))
9687 tree tem = TREE_OPERAND (arg1, 0);
9690 if (operand_equal_p (arg0, tem, 0))
9692 t1 = build_int_cst_type (type, -1);
9693 return omit_one_operand_loc (loc, type, t1, arg0);
9697 /* X + (X / CST) * -CST is X % CST. */
9698 if (TREE_CODE (arg1) == MULT_EXPR
9699 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
9700 && operand_equal_p (arg0,
9701 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
9703 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
9704 tree cst1 = TREE_OPERAND (arg1, 1);
9705 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
9707 if (sum && integer_zerop (sum))
9708 return fold_convert_loc (loc, type,
9709 fold_build2_loc (loc, TRUNC_MOD_EXPR,
9710 TREE_TYPE (arg0), arg0,
9715 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
9716 same or one. Make sure type is not saturating.
9717 fold_plusminus_mult_expr will re-associate. */
9718 if ((TREE_CODE (arg0) == MULT_EXPR
9719 || TREE_CODE (arg1) == MULT_EXPR)
9720 && !TYPE_SATURATING (type)
9721 && (!FLOAT_TYPE_P (type) || flag_associative_math))
9723 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
9728 if (! FLOAT_TYPE_P (type))
9730 if (integer_zerop (arg1))
9731 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9733 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
9734 with a constant, and the two constants have no bits in common,
9735 we should treat this as a BIT_IOR_EXPR since this may produce more
9737 if (TREE_CODE (arg0) == BIT_AND_EXPR
9738 && TREE_CODE (arg1) == BIT_AND_EXPR
9739 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9740 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9741 && integer_zerop (const_binop (BIT_AND_EXPR,
9742 TREE_OPERAND (arg0, 1),
9743 TREE_OPERAND (arg1, 1))))
9745 code = BIT_IOR_EXPR;
9749 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
9750 (plus (plus (mult) (mult)) (foo)) so that we can
9751 take advantage of the factoring cases below. */
9752 if (((TREE_CODE (arg0) == PLUS_EXPR
9753 || TREE_CODE (arg0) == MINUS_EXPR)
9754 && TREE_CODE (arg1) == MULT_EXPR)
9755 || ((TREE_CODE (arg1) == PLUS_EXPR
9756 || TREE_CODE (arg1) == MINUS_EXPR)
9757 && TREE_CODE (arg0) == MULT_EXPR))
9759 tree parg0, parg1, parg, marg;
9760 enum tree_code pcode;
9762 if (TREE_CODE (arg1) == MULT_EXPR)
9763 parg = arg0, marg = arg1;
9765 parg = arg1, marg = arg0;
9766 pcode = TREE_CODE (parg);
9767 parg0 = TREE_OPERAND (parg, 0);
9768 parg1 = TREE_OPERAND (parg, 1);
9772 if (TREE_CODE (parg0) == MULT_EXPR
9773 && TREE_CODE (parg1) != MULT_EXPR)
9774 return fold_build2_loc (loc, pcode, type,
9775 fold_build2_loc (loc, PLUS_EXPR, type,
9776 fold_convert_loc (loc, type,
9778 fold_convert_loc (loc, type,
9780 fold_convert_loc (loc, type, parg1));
9781 if (TREE_CODE (parg0) != MULT_EXPR
9782 && TREE_CODE (parg1) == MULT_EXPR)
9784 fold_build2_loc (loc, PLUS_EXPR, type,
9785 fold_convert_loc (loc, type, parg0),
9786 fold_build2_loc (loc, pcode, type,
9787 fold_convert_loc (loc, type, marg),
9788 fold_convert_loc (loc, type,
9794 /* See if ARG1 is zero and X + ARG1 reduces to X. */
9795 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
9796 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
9798 /* Likewise if the operands are reversed. */
9799 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
9800 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
9802 /* Convert X + -C into X - C. */
9803 if (TREE_CODE (arg1) == REAL_CST
9804 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
9806 tem = fold_negate_const (arg1, type);
9807 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
9808 return fold_build2_loc (loc, MINUS_EXPR, type,
9809 fold_convert_loc (loc, type, arg0),
9810 fold_convert_loc (loc, type, tem));
9813 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
9814 to __complex__ ( x, y ). This is not the same for SNaNs or
9815 if signed zeros are involved. */
9816 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
9817 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
9818 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
9820 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
9821 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
9822 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
9823 bool arg0rz = false, arg0iz = false;
9824 if ((arg0r && (arg0rz = real_zerop (arg0r)))
9825 || (arg0i && (arg0iz = real_zerop (arg0i))))
9827 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
9828 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
9829 if (arg0rz && arg1i && real_zerop (arg1i))
9831 tree rp = arg1r ? arg1r
9832 : build1 (REALPART_EXPR, rtype, arg1);
9833 tree ip = arg0i ? arg0i
9834 : build1 (IMAGPART_EXPR, rtype, arg0);
9835 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9837 else if (arg0iz && arg1r && real_zerop (arg1r))
9839 tree rp = arg0r ? arg0r
9840 : build1 (REALPART_EXPR, rtype, arg0);
9841 tree ip = arg1i ? arg1i
9842 : build1 (IMAGPART_EXPR, rtype, arg1);
9843 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
9848 if (flag_unsafe_math_optimizations
9849 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
9850 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
9851 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
9854 /* Convert x+x into x*2.0. */
9855 if (operand_equal_p (arg0, arg1, 0)
9856 && SCALAR_FLOAT_TYPE_P (type))
9857 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
9858 build_real (type, dconst2));
9860 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
9861 We associate floats only if the user has specified
9862 -fassociative-math. */
9863 if (flag_associative_math
9864 && TREE_CODE (arg1) == PLUS_EXPR
9865 && TREE_CODE (arg0) != MULT_EXPR)
9867 tree tree10 = TREE_OPERAND (arg1, 0);
9868 tree tree11 = TREE_OPERAND (arg1, 1);
9869 if (TREE_CODE (tree11) == MULT_EXPR
9870 && TREE_CODE (tree10) == MULT_EXPR)
9873 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
9874 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
9877 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
9878 We associate floats only if the user has specified
9879 -fassociative-math. */
9880 if (flag_associative_math
9881 && TREE_CODE (arg0) == PLUS_EXPR
9882 && TREE_CODE (arg1) != MULT_EXPR)
9884 tree tree00 = TREE_OPERAND (arg0, 0);
9885 tree tree01 = TREE_OPERAND (arg0, 1);
9886 if (TREE_CODE (tree01) == MULT_EXPR
9887 && TREE_CODE (tree00) == MULT_EXPR)
9890 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
9891 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
9897 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
9898 is a rotate of A by C1 bits. */
9899 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
9900 is a rotate of A by B bits. */
9902 enum tree_code code0, code1;
9904 code0 = TREE_CODE (arg0);
9905 code1 = TREE_CODE (arg1);
9906 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
9907 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
9908 && operand_equal_p (TREE_OPERAND (arg0, 0),
9909 TREE_OPERAND (arg1, 0), 0)
9910 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
9911 TYPE_UNSIGNED (rtype))
9912 /* Only create rotates in complete modes. Other cases are not
9913 expanded properly. */
9914 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
9916 tree tree01, tree11;
9917 enum tree_code code01, code11;
9919 tree01 = TREE_OPERAND (arg0, 1);
9920 tree11 = TREE_OPERAND (arg1, 1);
9921 STRIP_NOPS (tree01);
9922 STRIP_NOPS (tree11);
9923 code01 = TREE_CODE (tree01);
9924 code11 = TREE_CODE (tree11);
9925 if (code01 == INTEGER_CST
9926 && code11 == INTEGER_CST
9927 && TREE_INT_CST_HIGH (tree01) == 0
9928 && TREE_INT_CST_HIGH (tree11) == 0
9929 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
9930 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
9932 tem = build2 (LROTATE_EXPR,
9933 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9934 TREE_OPERAND (arg0, 0),
9935 code0 == LSHIFT_EXPR
9937 SET_EXPR_LOCATION (tem, loc);
9938 return fold_convert_loc (loc, type, tem);
9940 else if (code11 == MINUS_EXPR)
9942 tree tree110, tree111;
9943 tree110 = TREE_OPERAND (tree11, 0);
9944 tree111 = TREE_OPERAND (tree11, 1);
9945 STRIP_NOPS (tree110);
9946 STRIP_NOPS (tree111);
9947 if (TREE_CODE (tree110) == INTEGER_CST
9948 && 0 == compare_tree_int (tree110,
9950 (TREE_TYPE (TREE_OPERAND
9952 && operand_equal_p (tree01, tree111, 0))
9954 fold_convert_loc (loc, type,
9955 build2 ((code0 == LSHIFT_EXPR
9958 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9959 TREE_OPERAND (arg0, 0), tree01));
9961 else if (code01 == MINUS_EXPR)
9963 tree tree010, tree011;
9964 tree010 = TREE_OPERAND (tree01, 0);
9965 tree011 = TREE_OPERAND (tree01, 1);
9966 STRIP_NOPS (tree010);
9967 STRIP_NOPS (tree011);
9968 if (TREE_CODE (tree010) == INTEGER_CST
9969 && 0 == compare_tree_int (tree010,
9971 (TREE_TYPE (TREE_OPERAND
9973 && operand_equal_p (tree11, tree011, 0))
9974 return fold_convert_loc
9976 build2 ((code0 != LSHIFT_EXPR
9979 TREE_TYPE (TREE_OPERAND (arg0, 0)),
9980 TREE_OPERAND (arg0, 0), tree11));
9986 /* In most languages, can't associate operations on floats through
9987 parentheses. Rather than remember where the parentheses were, we
9988 don't associate floats at all, unless the user has specified
9990 And, we need to make sure type is not saturating. */
9992 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
9993 && !TYPE_SATURATING (type))
9995 tree var0, con0, lit0, minus_lit0;
9996 tree var1, con1, lit1, minus_lit1;
9999 /* Split both trees into variables, constants, and literals. Then
10000 associate each group together, the constants with literals,
10001 then the result with variables. This increases the chances of
10002 literals being recombined later and of generating relocatable
10003 expressions for the sum of a constant and literal. */
10004 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10005 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10006 code == MINUS_EXPR);
10008 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10009 if (code == MINUS_EXPR)
10012 /* With undefined overflow we can only associate constants with one
10013 variable, and constants whose association doesn't overflow. */
10014 if ((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10015 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10022 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10023 tmp0 = TREE_OPERAND (tmp0, 0);
10024 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10025 tmp1 = TREE_OPERAND (tmp1, 0);
10026 /* The only case we can still associate with two variables
10027 is if they are the same, modulo negation. */
10028 if (!operand_equal_p (tmp0, tmp1, 0))
10032 if (ok && lit0 && lit1)
10034 tree tmp0 = fold_convert (type, lit0);
10035 tree tmp1 = fold_convert (type, lit1);
10037 if (!TREE_OVERFLOW (tmp0) && !TREE_OVERFLOW (tmp1)
10038 && TREE_OVERFLOW (fold_build2 (code, type, tmp0, tmp1)))
10043 /* Only do something if we found more than two objects. Otherwise,
10044 nothing has changed and we risk infinite recursion. */
10046 && (2 < ((var0 != 0) + (var1 != 0)
10047 + (con0 != 0) + (con1 != 0)
10048 + (lit0 != 0) + (lit1 != 0)
10049 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10051 var0 = associate_trees (loc, var0, var1, code, type);
10052 con0 = associate_trees (loc, con0, con1, code, type);
10053 lit0 = associate_trees (loc, lit0, lit1, code, type);
10054 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10056 /* Preserve the MINUS_EXPR if the negative part of the literal is
10057 greater than the positive part. Otherwise, the multiplicative
10058 folding code (i.e extract_muldiv) may be fooled in case
10059 unsigned constants are subtracted, like in the following
10060 example: ((X*2 + 4) - 8U)/2. */
10061 if (minus_lit0 && lit0)
10063 if (TREE_CODE (lit0) == INTEGER_CST
10064 && TREE_CODE (minus_lit0) == INTEGER_CST
10065 && tree_int_cst_lt (lit0, minus_lit0))
10067 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10073 lit0 = associate_trees (loc, lit0, minus_lit0,
10082 fold_convert_loc (loc, type,
10083 associate_trees (loc, var0, minus_lit0,
10084 MINUS_EXPR, type));
10087 con0 = associate_trees (loc, con0, minus_lit0,
10090 fold_convert_loc (loc, type,
10091 associate_trees (loc, var0, con0,
10096 con0 = associate_trees (loc, con0, lit0, code, type);
10098 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10106 /* Pointer simplifications for subtraction, simple reassociations. */
10107 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10109 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10110 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10111 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10113 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10114 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10115 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10116 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10117 return fold_build2_loc (loc, PLUS_EXPR, type,
10118 fold_build2_loc (loc, MINUS_EXPR, type,
10120 fold_build2_loc (loc, MINUS_EXPR, type,
10123 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10124 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10126 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10127 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10128 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10129 fold_convert_loc (loc, type, arg1));
10131 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10134 /* A - (-B) -> A + B */
10135 if (TREE_CODE (arg1) == NEGATE_EXPR)
10136 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10137 fold_convert_loc (loc, type,
10138 TREE_OPERAND (arg1, 0)));
10139 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10140 if (TREE_CODE (arg0) == NEGATE_EXPR
10141 && (FLOAT_TYPE_P (type)
10142 || INTEGRAL_TYPE_P (type))
10143 && negate_expr_p (arg1)
10144 && reorder_operands_p (arg0, arg1))
10145 return fold_build2_loc (loc, MINUS_EXPR, type,
10146 fold_convert_loc (loc, type,
10147 negate_expr (arg1)),
10148 fold_convert_loc (loc, type,
10149 TREE_OPERAND (arg0, 0)));
10150 /* Convert -A - 1 to ~A. */
10151 if (INTEGRAL_TYPE_P (type)
10152 && TREE_CODE (arg0) == NEGATE_EXPR
10153 && integer_onep (arg1)
10154 && !TYPE_OVERFLOW_TRAPS (type))
10155 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10156 fold_convert_loc (loc, type,
10157 TREE_OPERAND (arg0, 0)));
10159 /* Convert -1 - A to ~A. */
10160 if (INTEGRAL_TYPE_P (type)
10161 && integer_all_onesp (arg0))
10162 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10165 /* X - (X / CST) * CST is X % CST. */
10166 if (INTEGRAL_TYPE_P (type)
10167 && TREE_CODE (arg1) == MULT_EXPR
10168 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10169 && operand_equal_p (arg0,
10170 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10171 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10172 TREE_OPERAND (arg1, 1), 0))
10174 fold_convert_loc (loc, type,
10175 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10176 arg0, TREE_OPERAND (arg1, 1)));
10178 if (! FLOAT_TYPE_P (type))
10180 if (integer_zerop (arg0))
10181 return negate_expr (fold_convert_loc (loc, type, arg1));
10182 if (integer_zerop (arg1))
10183 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10185 /* Fold A - (A & B) into ~B & A. */
10186 if (!TREE_SIDE_EFFECTS (arg0)
10187 && TREE_CODE (arg1) == BIT_AND_EXPR)
10189 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10191 tree arg10 = fold_convert_loc (loc, type,
10192 TREE_OPERAND (arg1, 0));
10193 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10194 fold_build1_loc (loc, BIT_NOT_EXPR,
10196 fold_convert_loc (loc, type, arg0));
10198 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10200 tree arg11 = fold_convert_loc (loc,
10201 type, TREE_OPERAND (arg1, 1));
10202 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10203 fold_build1_loc (loc, BIT_NOT_EXPR,
10205 fold_convert_loc (loc, type, arg0));
10209 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10210 any power of 2 minus 1. */
10211 if (TREE_CODE (arg0) == BIT_AND_EXPR
10212 && TREE_CODE (arg1) == BIT_AND_EXPR
10213 && operand_equal_p (TREE_OPERAND (arg0, 0),
10214 TREE_OPERAND (arg1, 0), 0))
10216 tree mask0 = TREE_OPERAND (arg0, 1);
10217 tree mask1 = TREE_OPERAND (arg1, 1);
10218 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10220 if (operand_equal_p (tem, mask1, 0))
10222 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10223 TREE_OPERAND (arg0, 0), mask1);
10224 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10229 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10230 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10231 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10233 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10234 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10235 (-ARG1 + ARG0) reduces to -ARG1. */
10236 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10237 return negate_expr (fold_convert_loc (loc, type, arg1));
10239 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10240 __complex__ ( x, -y ). This is not the same for SNaNs or if
10241 signed zeros are involved. */
10242 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10243 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10244 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10246 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10247 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10248 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10249 bool arg0rz = false, arg0iz = false;
10250 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10251 || (arg0i && (arg0iz = real_zerop (arg0i))))
10253 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10254 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10255 if (arg0rz && arg1i && real_zerop (arg1i))
10257 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10259 : build1 (REALPART_EXPR, rtype, arg1));
10260 tree ip = arg0i ? arg0i
10261 : build1 (IMAGPART_EXPR, rtype, arg0);
10262 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10264 else if (arg0iz && arg1r && real_zerop (arg1r))
10266 tree rp = arg0r ? arg0r
10267 : build1 (REALPART_EXPR, rtype, arg0);
10268 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10270 : build1 (IMAGPART_EXPR, rtype, arg1));
10271 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10276 /* Fold &x - &x. This can happen from &x.foo - &x.
10277 This is unsafe for certain floats even in non-IEEE formats.
10278 In IEEE, it is unsafe because it does wrong for NaNs.
10279 Also note that operand_equal_p is always false if an operand
10282 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10283 && operand_equal_p (arg0, arg1, 0))
10284 return fold_convert_loc (loc, type, integer_zero_node);
10286 /* A - B -> A + (-B) if B is easily negatable. */
10287 if (negate_expr_p (arg1)
10288 && ((FLOAT_TYPE_P (type)
10289 /* Avoid this transformation if B is a positive REAL_CST. */
10290 && (TREE_CODE (arg1) != REAL_CST
10291 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10292 || INTEGRAL_TYPE_P (type)))
10293 return fold_build2_loc (loc, PLUS_EXPR, type,
10294 fold_convert_loc (loc, type, arg0),
10295 fold_convert_loc (loc, type,
10296 negate_expr (arg1)));
10298 /* Try folding difference of addresses. */
10300 HOST_WIDE_INT diff;
10302 if ((TREE_CODE (arg0) == ADDR_EXPR
10303 || TREE_CODE (arg1) == ADDR_EXPR)
10304 && ptr_difference_const (arg0, arg1, &diff))
10305 return build_int_cst_type (type, diff);
10308 /* Fold &a[i] - &a[j] to i-j. */
10309 if (TREE_CODE (arg0) == ADDR_EXPR
10310 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10311 && TREE_CODE (arg1) == ADDR_EXPR
10312 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10314 tree aref0 = TREE_OPERAND (arg0, 0);
10315 tree aref1 = TREE_OPERAND (arg1, 0);
10316 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10317 TREE_OPERAND (aref1, 0), 0))
10319 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
10320 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
10321 tree esz = array_ref_element_size (aref0);
10322 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10323 return fold_build2_loc (loc, MULT_EXPR, type, diff,
10324 fold_convert_loc (loc, type, esz));
10329 if (FLOAT_TYPE_P (type)
10330 && flag_unsafe_math_optimizations
10331 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10332 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10333 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10336 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10337 same or one. Make sure type is not saturating.
10338 fold_plusminus_mult_expr will re-associate. */
10339 if ((TREE_CODE (arg0) == MULT_EXPR
10340 || TREE_CODE (arg1) == MULT_EXPR)
10341 && !TYPE_SATURATING (type)
10342 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10344 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10352 /* (-A) * (-B) -> A * B */
10353 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10354 return fold_build2_loc (loc, MULT_EXPR, type,
10355 fold_convert_loc (loc, type,
10356 TREE_OPERAND (arg0, 0)),
10357 fold_convert_loc (loc, type,
10358 negate_expr (arg1)));
10359 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10360 return fold_build2_loc (loc, MULT_EXPR, type,
10361 fold_convert_loc (loc, type,
10362 negate_expr (arg0)),
10363 fold_convert_loc (loc, type,
10364 TREE_OPERAND (arg1, 0)));
10366 if (! FLOAT_TYPE_P (type))
10368 if (integer_zerop (arg1))
10369 return omit_one_operand_loc (loc, type, arg1, arg0);
10370 if (integer_onep (arg1))
10371 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10372 /* Transform x * -1 into -x. Make sure to do the negation
10373 on the original operand with conversions not stripped
10374 because we can only strip non-sign-changing conversions. */
10375 if (integer_all_onesp (arg1))
10376 return fold_convert_loc (loc, type, negate_expr (op0));
10377 /* Transform x * -C into -x * C if x is easily negatable. */
10378 if (TREE_CODE (arg1) == INTEGER_CST
10379 && tree_int_cst_sgn (arg1) == -1
10380 && negate_expr_p (arg0)
10381 && (tem = negate_expr (arg1)) != arg1
10382 && !TREE_OVERFLOW (tem))
10383 return fold_build2_loc (loc, MULT_EXPR, type,
10384 fold_convert_loc (loc, type,
10385 negate_expr (arg0)),
10388 /* (a * (1 << b)) is (a << b) */
10389 if (TREE_CODE (arg1) == LSHIFT_EXPR
10390 && integer_onep (TREE_OPERAND (arg1, 0)))
10391 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
10392 TREE_OPERAND (arg1, 1));
10393 if (TREE_CODE (arg0) == LSHIFT_EXPR
10394 && integer_onep (TREE_OPERAND (arg0, 0)))
10395 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
10396 TREE_OPERAND (arg0, 1));
10398 /* (A + A) * C -> A * 2 * C */
10399 if (TREE_CODE (arg0) == PLUS_EXPR
10400 && TREE_CODE (arg1) == INTEGER_CST
10401 && operand_equal_p (TREE_OPERAND (arg0, 0),
10402 TREE_OPERAND (arg0, 1), 0))
10403 return fold_build2_loc (loc, MULT_EXPR, type,
10404 omit_one_operand_loc (loc, type,
10405 TREE_OPERAND (arg0, 0),
10406 TREE_OPERAND (arg0, 1)),
10407 fold_build2_loc (loc, MULT_EXPR, type,
10408 build_int_cst (type, 2) , arg1));
10410 strict_overflow_p = false;
10411 if (TREE_CODE (arg1) == INTEGER_CST
10412 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
10413 &strict_overflow_p)))
10415 if (strict_overflow_p)
10416 fold_overflow_warning (("assuming signed overflow does not "
10417 "occur when simplifying "
10419 WARN_STRICT_OVERFLOW_MISC);
10420 return fold_convert_loc (loc, type, tem);
10423 /* Optimize z * conj(z) for integer complex numbers. */
10424 if (TREE_CODE (arg0) == CONJ_EXPR
10425 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10426 return fold_mult_zconjz (loc, type, arg1);
10427 if (TREE_CODE (arg1) == CONJ_EXPR
10428 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10429 return fold_mult_zconjz (loc, type, arg0);
10433 /* Maybe fold x * 0 to 0. The expressions aren't the same
10434 when x is NaN, since x * 0 is also NaN. Nor are they the
10435 same in modes with signed zeros, since multiplying a
10436 negative value by 0 gives -0, not +0. */
10437 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10438 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10439 && real_zerop (arg1))
10440 return omit_one_operand_loc (loc, type, arg1, arg0);
10441 /* In IEEE floating point, x*1 is not equivalent to x for snans.
10442 Likewise for complex arithmetic with signed zeros. */
10443 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10444 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10445 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10446 && real_onep (arg1))
10447 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10449 /* Transform x * -1.0 into -x. */
10450 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10451 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10452 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10453 && real_minus_onep (arg1))
10454 return fold_convert_loc (loc, type, negate_expr (arg0));
10456 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
10457 the result for floating point types due to rounding so it is applied
10458 only if -fassociative-math was specify. */
10459 if (flag_associative_math
10460 && TREE_CODE (arg0) == RDIV_EXPR
10461 && TREE_CODE (arg1) == REAL_CST
10462 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
10464 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
10467 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
10468 TREE_OPERAND (arg0, 1));
10471 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
10472 if (operand_equal_p (arg0, arg1, 0))
10474 tree tem = fold_strip_sign_ops (arg0);
10475 if (tem != NULL_TREE)
10477 tem = fold_convert_loc (loc, type, tem);
10478 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
10482 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
10483 This is not the same for NaNs or if signed zeros are
10485 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
10486 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10487 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
10488 && TREE_CODE (arg1) == COMPLEX_CST
10489 && real_zerop (TREE_REALPART (arg1)))
10491 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10492 if (real_onep (TREE_IMAGPART (arg1)))
10494 fold_build2_loc (loc, COMPLEX_EXPR, type,
10495 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
10497 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
10498 else if (real_minus_onep (TREE_IMAGPART (arg1)))
10500 fold_build2_loc (loc, COMPLEX_EXPR, type,
10501 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
10502 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
10506 /* Optimize z * conj(z) for floating point complex numbers.
10507 Guarded by flag_unsafe_math_optimizations as non-finite
10508 imaginary components don't produce scalar results. */
10509 if (flag_unsafe_math_optimizations
10510 && TREE_CODE (arg0) == CONJ_EXPR
10511 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10512 return fold_mult_zconjz (loc, type, arg1);
10513 if (flag_unsafe_math_optimizations
10514 && TREE_CODE (arg1) == CONJ_EXPR
10515 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10516 return fold_mult_zconjz (loc, type, arg0);
10518 if (flag_unsafe_math_optimizations)
10520 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
10521 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
10523 /* Optimizations of root(...)*root(...). */
10524 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
10527 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10528 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10530 /* Optimize sqrt(x)*sqrt(x) as x. */
10531 if (BUILTIN_SQRT_P (fcode0)
10532 && operand_equal_p (arg00, arg10, 0)
10533 && ! HONOR_SNANS (TYPE_MODE (type)))
10536 /* Optimize root(x)*root(y) as root(x*y). */
10537 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10538 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
10539 return build_call_expr_loc (loc, rootfn, 1, arg);
10542 /* Optimize expN(x)*expN(y) as expN(x+y). */
10543 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
10545 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10546 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10547 CALL_EXPR_ARG (arg0, 0),
10548 CALL_EXPR_ARG (arg1, 0));
10549 return build_call_expr_loc (loc, expfn, 1, arg);
10552 /* Optimizations of pow(...)*pow(...). */
10553 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
10554 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
10555 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
10557 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10558 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10559 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10560 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10562 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
10563 if (operand_equal_p (arg01, arg11, 0))
10565 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10566 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
10568 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
10571 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
10572 if (operand_equal_p (arg00, arg10, 0))
10574 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10575 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
10577 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
10581 /* Optimize tan(x)*cos(x) as sin(x). */
10582 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
10583 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
10584 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
10585 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
10586 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
10587 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
10588 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
10589 CALL_EXPR_ARG (arg1, 0), 0))
10591 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
10593 if (sinfn != NULL_TREE)
10594 return build_call_expr_loc (loc, sinfn, 1,
10595 CALL_EXPR_ARG (arg0, 0));
10598 /* Optimize x*pow(x,c) as pow(x,c+1). */
10599 if (fcode1 == BUILT_IN_POW
10600 || fcode1 == BUILT_IN_POWF
10601 || fcode1 == BUILT_IN_POWL)
10603 tree arg10 = CALL_EXPR_ARG (arg1, 0);
10604 tree arg11 = CALL_EXPR_ARG (arg1, 1);
10605 if (TREE_CODE (arg11) == REAL_CST
10606 && !TREE_OVERFLOW (arg11)
10607 && operand_equal_p (arg0, arg10, 0))
10609 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
10613 c = TREE_REAL_CST (arg11);
10614 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10615 arg = build_real (type, c);
10616 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10620 /* Optimize pow(x,c)*x as pow(x,c+1). */
10621 if (fcode0 == BUILT_IN_POW
10622 || fcode0 == BUILT_IN_POWF
10623 || fcode0 == BUILT_IN_POWL)
10625 tree arg00 = CALL_EXPR_ARG (arg0, 0);
10626 tree arg01 = CALL_EXPR_ARG (arg0, 1);
10627 if (TREE_CODE (arg01) == REAL_CST
10628 && !TREE_OVERFLOW (arg01)
10629 && operand_equal_p (arg1, arg00, 0))
10631 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
10635 c = TREE_REAL_CST (arg01);
10636 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
10637 arg = build_real (type, c);
10638 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
10642 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
10643 if (optimize_function_for_speed_p (cfun)
10644 && operand_equal_p (arg0, arg1, 0))
10646 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
10650 tree arg = build_real (type, dconst2);
10651 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
10660 if (integer_all_onesp (arg1))
10661 return omit_one_operand_loc (loc, type, arg1, arg0);
10662 if (integer_zerop (arg1))
10663 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10664 if (operand_equal_p (arg0, arg1, 0))
10665 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10667 /* ~X | X is -1. */
10668 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10669 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10671 t1 = fold_convert_loc (loc, type, integer_zero_node);
10672 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10673 return omit_one_operand_loc (loc, type, t1, arg1);
10676 /* X | ~X is -1. */
10677 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10678 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10680 t1 = fold_convert_loc (loc, type, integer_zero_node);
10681 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10682 return omit_one_operand_loc (loc, type, t1, arg0);
10685 /* Canonicalize (X & C1) | C2. */
10686 if (TREE_CODE (arg0) == BIT_AND_EXPR
10687 && TREE_CODE (arg1) == INTEGER_CST
10688 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10690 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
10691 int width = TYPE_PRECISION (type), w;
10692 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
10693 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
10694 hi2 = TREE_INT_CST_HIGH (arg1);
10695 lo2 = TREE_INT_CST_LOW (arg1);
10697 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
10698 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
10699 return omit_one_operand_loc (loc, type, arg1,
10700 TREE_OPERAND (arg0, 0));
10702 if (width > HOST_BITS_PER_WIDE_INT)
10704 mhi = (unsigned HOST_WIDE_INT) -1
10705 >> (2 * HOST_BITS_PER_WIDE_INT - width);
10711 mlo = (unsigned HOST_WIDE_INT) -1
10712 >> (HOST_BITS_PER_WIDE_INT - width);
10715 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
10716 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
10717 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10718 TREE_OPERAND (arg0, 0), arg1);
10720 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
10721 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
10722 mode which allows further optimizations. */
10729 for (w = BITS_PER_UNIT;
10730 w <= width && w <= HOST_BITS_PER_WIDE_INT;
10733 unsigned HOST_WIDE_INT mask
10734 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
10735 if (((lo1 | lo2) & mask) == mask
10736 && (lo1 & ~mask) == 0 && hi1 == 0)
10743 if (hi3 != hi1 || lo3 != lo1)
10744 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
10745 fold_build2_loc (loc, BIT_AND_EXPR, type,
10746 TREE_OPERAND (arg0, 0),
10747 build_int_cst_wide (type,
10752 /* (X & Y) | Y is (X, Y). */
10753 if (TREE_CODE (arg0) == BIT_AND_EXPR
10754 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10755 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10756 /* (X & Y) | X is (Y, X). */
10757 if (TREE_CODE (arg0) == BIT_AND_EXPR
10758 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10759 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10760 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
10761 /* X | (X & Y) is (Y, X). */
10762 if (TREE_CODE (arg1) == BIT_AND_EXPR
10763 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
10764 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
10765 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
10766 /* X | (Y & X) is (Y, X). */
10767 if (TREE_CODE (arg1) == BIT_AND_EXPR
10768 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10769 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10770 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
10772 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
10773 if (t1 != NULL_TREE)
10776 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
10778 This results in more efficient code for machines without a NAND
10779 instruction. Combine will canonicalize to the first form
10780 which will allow use of NAND instructions provided by the
10781 backend if they exist. */
10782 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10783 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10786 fold_build1_loc (loc, BIT_NOT_EXPR, type,
10787 build2 (BIT_AND_EXPR, type,
10788 fold_convert_loc (loc, type,
10789 TREE_OPERAND (arg0, 0)),
10790 fold_convert_loc (loc, type,
10791 TREE_OPERAND (arg1, 0))));
10794 /* See if this can be simplified into a rotate first. If that
10795 is unsuccessful continue in the association code. */
10799 if (integer_zerop (arg1))
10800 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10801 if (integer_all_onesp (arg1))
10802 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
10803 if (operand_equal_p (arg0, arg1, 0))
10804 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10806 /* ~X ^ X is -1. */
10807 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10808 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10810 t1 = fold_convert_loc (loc, type, integer_zero_node);
10811 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10812 return omit_one_operand_loc (loc, type, t1, arg1);
10815 /* X ^ ~X is -1. */
10816 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10817 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10819 t1 = fold_convert_loc (loc, type, integer_zero_node);
10820 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
10821 return omit_one_operand_loc (loc, type, t1, arg0);
10824 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
10825 with a constant, and the two constants have no bits in common,
10826 we should treat this as a BIT_IOR_EXPR since this may produce more
10827 simplifications. */
10828 if (TREE_CODE (arg0) == BIT_AND_EXPR
10829 && TREE_CODE (arg1) == BIT_AND_EXPR
10830 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10831 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10832 && integer_zerop (const_binop (BIT_AND_EXPR,
10833 TREE_OPERAND (arg0, 1),
10834 TREE_OPERAND (arg1, 1))))
10836 code = BIT_IOR_EXPR;
10840 /* (X | Y) ^ X -> Y & ~ X*/
10841 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10842 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10844 tree t2 = TREE_OPERAND (arg0, 1);
10845 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10847 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10848 fold_convert_loc (loc, type, t2),
10849 fold_convert_loc (loc, type, t1));
10853 /* (Y | X) ^ X -> Y & ~ X*/
10854 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10855 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10857 tree t2 = TREE_OPERAND (arg0, 0);
10858 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
10860 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10861 fold_convert_loc (loc, type, t2),
10862 fold_convert_loc (loc, type, t1));
10866 /* X ^ (X | Y) -> Y & ~ X*/
10867 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10868 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
10870 tree t2 = TREE_OPERAND (arg1, 1);
10871 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10873 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10874 fold_convert_loc (loc, type, t2),
10875 fold_convert_loc (loc, type, t1));
10879 /* X ^ (Y | X) -> Y & ~ X*/
10880 if (TREE_CODE (arg1) == BIT_IOR_EXPR
10881 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
10883 tree t2 = TREE_OPERAND (arg1, 0);
10884 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
10886 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
10887 fold_convert_loc (loc, type, t2),
10888 fold_convert_loc (loc, type, t1));
10892 /* Convert ~X ^ ~Y to X ^ Y. */
10893 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10894 && TREE_CODE (arg1) == BIT_NOT_EXPR)
10895 return fold_build2_loc (loc, code, type,
10896 fold_convert_loc (loc, type,
10897 TREE_OPERAND (arg0, 0)),
10898 fold_convert_loc (loc, type,
10899 TREE_OPERAND (arg1, 0)));
10901 /* Convert ~X ^ C to X ^ ~C. */
10902 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10903 && TREE_CODE (arg1) == INTEGER_CST)
10904 return fold_build2_loc (loc, code, type,
10905 fold_convert_loc (loc, type,
10906 TREE_OPERAND (arg0, 0)),
10907 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
10909 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
10910 if (TREE_CODE (arg0) == BIT_AND_EXPR
10911 && integer_onep (TREE_OPERAND (arg0, 1))
10912 && integer_onep (arg1))
10913 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
10914 build_int_cst (TREE_TYPE (arg0), 0));
10916 /* Fold (X & Y) ^ Y as ~X & Y. */
10917 if (TREE_CODE (arg0) == BIT_AND_EXPR
10918 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10920 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10921 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10922 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10923 fold_convert_loc (loc, type, arg1));
10925 /* Fold (X & Y) ^ X as ~Y & X. */
10926 if (TREE_CODE (arg0) == BIT_AND_EXPR
10927 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
10928 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
10930 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10931 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10932 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10933 fold_convert_loc (loc, type, arg1));
10935 /* Fold X ^ (X & Y) as X & ~Y. */
10936 if (TREE_CODE (arg1) == BIT_AND_EXPR
10937 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10939 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10940 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10941 fold_convert_loc (loc, type, arg0),
10942 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
10944 /* Fold X ^ (Y & X) as ~Y & X. */
10945 if (TREE_CODE (arg1) == BIT_AND_EXPR
10946 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
10947 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10949 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10950 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10951 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
10952 fold_convert_loc (loc, type, arg0));
10955 /* See if this can be simplified into a rotate first. If that
10956 is unsuccessful continue in the association code. */
10960 if (integer_all_onesp (arg1))
10961 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10962 if (integer_zerop (arg1))
10963 return omit_one_operand_loc (loc, type, arg1, arg0);
10964 if (operand_equal_p (arg0, arg1, 0))
10965 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10967 /* ~X & X is always zero. */
10968 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10969 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
10970 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
10972 /* X & ~X is always zero. */
10973 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10974 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10975 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
10977 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
10978 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10979 && TREE_CODE (arg1) == INTEGER_CST
10980 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
10982 tree tmp1 = fold_convert_loc (loc, type, arg1);
10983 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10984 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10985 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
10986 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
10988 fold_convert_loc (loc, type,
10989 fold_build2_loc (loc, BIT_IOR_EXPR,
10990 type, tmp2, tmp3));
10993 /* (X | Y) & Y is (X, Y). */
10994 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10995 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
10996 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
10997 /* (X | Y) & X is (Y, X). */
10998 if (TREE_CODE (arg0) == BIT_IOR_EXPR
10999 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11000 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11001 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11002 /* X & (X | Y) is (Y, X). */
11003 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11004 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11005 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11006 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11007 /* X & (Y | X) is (Y, X). */
11008 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11009 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11010 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11011 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11013 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11014 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11015 && integer_onep (TREE_OPERAND (arg0, 1))
11016 && integer_onep (arg1))
11018 tem = TREE_OPERAND (arg0, 0);
11019 return fold_build2_loc (loc, EQ_EXPR, type,
11020 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11021 build_int_cst (TREE_TYPE (tem), 1)),
11022 build_int_cst (TREE_TYPE (tem), 0));
11024 /* Fold ~X & 1 as (X & 1) == 0. */
11025 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11026 && integer_onep (arg1))
11028 tem = TREE_OPERAND (arg0, 0);
11029 return fold_build2_loc (loc, EQ_EXPR, type,
11030 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11031 build_int_cst (TREE_TYPE (tem), 1)),
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 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11075 if (t1 != NULL_TREE)
11077 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11078 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11079 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11082 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11084 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11085 && (~TREE_INT_CST_LOW (arg1)
11086 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11088 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11091 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11093 This results in more efficient code for machines without a NOR
11094 instruction. Combine will canonicalize to the first form
11095 which will allow use of NOR instructions provided by the
11096 backend if they exist. */
11097 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11098 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11100 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11101 build2 (BIT_IOR_EXPR, type,
11102 fold_convert_loc (loc, type,
11103 TREE_OPERAND (arg0, 0)),
11104 fold_convert_loc (loc, type,
11105 TREE_OPERAND (arg1, 0))));
11108 /* If arg0 is derived from the address of an object or function, we may
11109 be able to fold this expression using the object or function's
11111 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11113 unsigned HOST_WIDE_INT modulus, residue;
11114 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11116 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11117 integer_onep (arg1));
11119 /* This works because modulus is a power of 2. If this weren't the
11120 case, we'd have to replace it by its greatest power-of-2
11121 divisor: modulus & -modulus. */
11123 return build_int_cst (type, residue & low);
11126 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11127 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11128 if the new mask might be further optimized. */
11129 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11130 || TREE_CODE (arg0) == RSHIFT_EXPR)
11131 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11132 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11133 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11134 < TYPE_PRECISION (TREE_TYPE (arg0))
11135 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11136 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11138 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11139 unsigned HOST_WIDE_INT mask
11140 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11141 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11142 tree shift_type = TREE_TYPE (arg0);
11144 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11145 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11146 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11147 && TYPE_PRECISION (TREE_TYPE (arg0))
11148 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11150 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11151 tree arg00 = TREE_OPERAND (arg0, 0);
11152 /* See if more bits can be proven as zero because of
11154 if (TREE_CODE (arg00) == NOP_EXPR
11155 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11157 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11158 if (TYPE_PRECISION (inner_type)
11159 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11160 && TYPE_PRECISION (inner_type) < prec)
11162 prec = TYPE_PRECISION (inner_type);
11163 /* See if we can shorten the right shift. */
11165 shift_type = inner_type;
11168 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11169 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11170 zerobits <<= prec - shiftc;
11171 /* For arithmetic shift if sign bit could be set, zerobits
11172 can contain actually sign bits, so no transformation is
11173 possible, unless MASK masks them all away. In that
11174 case the shift needs to be converted into logical shift. */
11175 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11176 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11178 if ((mask & zerobits) == 0)
11179 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11185 /* ((X << 16) & 0xff00) is (X, 0). */
11186 if ((mask & zerobits) == mask)
11187 return omit_one_operand_loc (loc, type,
11188 build_int_cst (type, 0), arg0);
11190 newmask = mask | zerobits;
11191 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11195 /* Only do the transformation if NEWMASK is some integer
11197 for (prec = BITS_PER_UNIT;
11198 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11199 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11201 if (prec < HOST_BITS_PER_WIDE_INT
11202 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11206 if (shift_type != TREE_TYPE (arg0))
11208 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11209 fold_convert_loc (loc, shift_type,
11210 TREE_OPERAND (arg0, 0)),
11211 TREE_OPERAND (arg0, 1));
11212 tem = fold_convert_loc (loc, type, tem);
11216 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11217 if (!tree_int_cst_equal (newmaskt, arg1))
11218 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11226 /* Don't touch a floating-point divide by zero unless the mode
11227 of the constant can represent infinity. */
11228 if (TREE_CODE (arg1) == REAL_CST
11229 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11230 && real_zerop (arg1))
11233 /* Optimize A / A to 1.0 if we don't care about
11234 NaNs or Infinities. Skip the transformation
11235 for non-real operands. */
11236 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11237 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11238 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11239 && operand_equal_p (arg0, arg1, 0))
11241 tree r = build_real (TREE_TYPE (arg0), dconst1);
11243 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11246 /* The complex version of the above A / A optimization. */
11247 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11248 && operand_equal_p (arg0, arg1, 0))
11250 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11251 if (! HONOR_NANS (TYPE_MODE (elem_type))
11252 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11254 tree r = build_real (elem_type, dconst1);
11255 /* omit_two_operands will call fold_convert for us. */
11256 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11260 /* (-A) / (-B) -> A / B */
11261 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11262 return fold_build2_loc (loc, RDIV_EXPR, type,
11263 TREE_OPERAND (arg0, 0),
11264 negate_expr (arg1));
11265 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11266 return fold_build2_loc (loc, RDIV_EXPR, type,
11267 negate_expr (arg0),
11268 TREE_OPERAND (arg1, 0));
11270 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11271 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11272 && real_onep (arg1))
11273 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11275 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11276 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11277 && real_minus_onep (arg1))
11278 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11279 negate_expr (arg0)));
11281 /* If ARG1 is a constant, we can convert this to a multiply by the
11282 reciprocal. This does not have the same rounding properties,
11283 so only do this if -freciprocal-math. We can actually
11284 always safely do it if ARG1 is a power of two, but it's hard to
11285 tell if it is or not in a portable manner. */
11286 if (TREE_CODE (arg1) == REAL_CST)
11288 if (flag_reciprocal_math
11289 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11291 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11292 /* Find the reciprocal if optimizing and the result is exact. */
11296 r = TREE_REAL_CST (arg1);
11297 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11299 tem = build_real (type, r);
11300 return fold_build2_loc (loc, MULT_EXPR, type,
11301 fold_convert_loc (loc, type, arg0), tem);
11305 /* Convert A/B/C to A/(B*C). */
11306 if (flag_reciprocal_math
11307 && TREE_CODE (arg0) == RDIV_EXPR)
11308 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11309 fold_build2_loc (loc, MULT_EXPR, type,
11310 TREE_OPERAND (arg0, 1), arg1));
11312 /* Convert A/(B/C) to (A/B)*C. */
11313 if (flag_reciprocal_math
11314 && TREE_CODE (arg1) == RDIV_EXPR)
11315 return fold_build2_loc (loc, MULT_EXPR, type,
11316 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11317 TREE_OPERAND (arg1, 0)),
11318 TREE_OPERAND (arg1, 1));
11320 /* Convert C1/(X*C2) into (C1/C2)/X. */
11321 if (flag_reciprocal_math
11322 && TREE_CODE (arg1) == MULT_EXPR
11323 && TREE_CODE (arg0) == REAL_CST
11324 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11326 tree tem = const_binop (RDIV_EXPR, arg0,
11327 TREE_OPERAND (arg1, 1));
11329 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11330 TREE_OPERAND (arg1, 0));
11333 if (flag_unsafe_math_optimizations)
11335 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11336 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11338 /* Optimize sin(x)/cos(x) as tan(x). */
11339 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11340 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11341 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11342 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11343 CALL_EXPR_ARG (arg1, 0), 0))
11345 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11347 if (tanfn != NULL_TREE)
11348 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11351 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11352 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11353 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11354 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11355 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11356 CALL_EXPR_ARG (arg1, 0), 0))
11358 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11360 if (tanfn != NULL_TREE)
11362 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11363 CALL_EXPR_ARG (arg0, 0));
11364 return fold_build2_loc (loc, RDIV_EXPR, type,
11365 build_real (type, dconst1), tmp);
11369 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11370 NaNs or Infinities. */
11371 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11372 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11373 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11375 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11376 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11378 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11379 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11380 && operand_equal_p (arg00, arg01, 0))
11382 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11384 if (cosfn != NULL_TREE)
11385 return build_call_expr_loc (loc, cosfn, 1, arg00);
11389 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11390 NaNs or Infinities. */
11391 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11392 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11393 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11395 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11396 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11398 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11399 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11400 && operand_equal_p (arg00, arg01, 0))
11402 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11404 if (cosfn != NULL_TREE)
11406 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11407 return fold_build2_loc (loc, RDIV_EXPR, type,
11408 build_real (type, dconst1),
11414 /* Optimize pow(x,c)/x as pow(x,c-1). */
11415 if (fcode0 == BUILT_IN_POW
11416 || fcode0 == BUILT_IN_POWF
11417 || fcode0 == BUILT_IN_POWL)
11419 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11420 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11421 if (TREE_CODE (arg01) == REAL_CST
11422 && !TREE_OVERFLOW (arg01)
11423 && operand_equal_p (arg1, arg00, 0))
11425 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11429 c = TREE_REAL_CST (arg01);
11430 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11431 arg = build_real (type, c);
11432 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11436 /* Optimize a/root(b/c) into a*root(c/b). */
11437 if (BUILTIN_ROOT_P (fcode1))
11439 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11441 if (TREE_CODE (rootarg) == RDIV_EXPR)
11443 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11444 tree b = TREE_OPERAND (rootarg, 0);
11445 tree c = TREE_OPERAND (rootarg, 1);
11447 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
11449 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
11450 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
11454 /* Optimize x/expN(y) into x*expN(-y). */
11455 if (BUILTIN_EXPONENT_P (fcode1))
11457 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11458 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11459 arg1 = build_call_expr_loc (loc,
11461 fold_convert_loc (loc, type, arg));
11462 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11465 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11466 if (fcode1 == BUILT_IN_POW
11467 || fcode1 == BUILT_IN_POWF
11468 || fcode1 == BUILT_IN_POWL)
11470 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11471 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11472 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11473 tree neg11 = fold_convert_loc (loc, type,
11474 negate_expr (arg11));
11475 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
11476 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11481 case TRUNC_DIV_EXPR:
11482 case FLOOR_DIV_EXPR:
11483 /* Simplify A / (B << N) where A and B are positive and B is
11484 a power of 2, to A >> (N + log2(B)). */
11485 strict_overflow_p = false;
11486 if (TREE_CODE (arg1) == LSHIFT_EXPR
11487 && (TYPE_UNSIGNED (type)
11488 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11490 tree sval = TREE_OPERAND (arg1, 0);
11491 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11493 tree sh_cnt = TREE_OPERAND (arg1, 1);
11494 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11496 if (strict_overflow_p)
11497 fold_overflow_warning (("assuming signed overflow does not "
11498 "occur when simplifying A / (B << N)"),
11499 WARN_STRICT_OVERFLOW_MISC);
11501 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
11502 sh_cnt, build_int_cst (NULL_TREE, pow2));
11503 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11504 fold_convert_loc (loc, type, arg0), sh_cnt);
11508 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11509 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11510 if (INTEGRAL_TYPE_P (type)
11511 && TYPE_UNSIGNED (type)
11512 && code == FLOOR_DIV_EXPR)
11513 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
11517 case ROUND_DIV_EXPR:
11518 case CEIL_DIV_EXPR:
11519 case EXACT_DIV_EXPR:
11520 if (integer_onep (arg1))
11521 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11522 if (integer_zerop (arg1))
11524 /* X / -1 is -X. */
11525 if (!TYPE_UNSIGNED (type)
11526 && TREE_CODE (arg1) == INTEGER_CST
11527 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11528 && TREE_INT_CST_HIGH (arg1) == -1)
11529 return fold_convert_loc (loc, type, negate_expr (arg0));
11531 /* Convert -A / -B to A / B when the type is signed and overflow is
11533 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11534 && TREE_CODE (arg0) == NEGATE_EXPR
11535 && negate_expr_p (arg1))
11537 if (INTEGRAL_TYPE_P (type))
11538 fold_overflow_warning (("assuming signed overflow does not occur "
11539 "when distributing negation across "
11541 WARN_STRICT_OVERFLOW_MISC);
11542 return fold_build2_loc (loc, code, type,
11543 fold_convert_loc (loc, type,
11544 TREE_OPERAND (arg0, 0)),
11545 fold_convert_loc (loc, type,
11546 negate_expr (arg1)));
11548 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11549 && TREE_CODE (arg1) == NEGATE_EXPR
11550 && negate_expr_p (arg0))
11552 if (INTEGRAL_TYPE_P (type))
11553 fold_overflow_warning (("assuming signed overflow does not occur "
11554 "when distributing negation across "
11556 WARN_STRICT_OVERFLOW_MISC);
11557 return fold_build2_loc (loc, code, type,
11558 fold_convert_loc (loc, type,
11559 negate_expr (arg0)),
11560 fold_convert_loc (loc, type,
11561 TREE_OPERAND (arg1, 0)));
11564 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11565 operation, EXACT_DIV_EXPR.
11567 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11568 At one time others generated faster code, it's not clear if they do
11569 after the last round to changes to the DIV code in expmed.c. */
11570 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11571 && multiple_of_p (type, arg0, arg1))
11572 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
11574 strict_overflow_p = false;
11575 if (TREE_CODE (arg1) == INTEGER_CST
11576 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11577 &strict_overflow_p)))
11579 if (strict_overflow_p)
11580 fold_overflow_warning (("assuming signed overflow does not occur "
11581 "when simplifying division"),
11582 WARN_STRICT_OVERFLOW_MISC);
11583 return fold_convert_loc (loc, type, tem);
11588 case CEIL_MOD_EXPR:
11589 case FLOOR_MOD_EXPR:
11590 case ROUND_MOD_EXPR:
11591 case TRUNC_MOD_EXPR:
11592 /* X % 1 is always zero, but be sure to preserve any side
11594 if (integer_onep (arg1))
11595 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11597 /* X % 0, return X % 0 unchanged so that we can get the
11598 proper warnings and errors. */
11599 if (integer_zerop (arg1))
11602 /* 0 % X is always zero, but be sure to preserve any side
11603 effects in X. Place this after checking for X == 0. */
11604 if (integer_zerop (arg0))
11605 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11607 /* X % -1 is zero. */
11608 if (!TYPE_UNSIGNED (type)
11609 && TREE_CODE (arg1) == INTEGER_CST
11610 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11611 && TREE_INT_CST_HIGH (arg1) == -1)
11612 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11614 /* X % -C is the same as X % C. */
11615 if (code == TRUNC_MOD_EXPR
11616 && !TYPE_UNSIGNED (type)
11617 && TREE_CODE (arg1) == INTEGER_CST
11618 && !TREE_OVERFLOW (arg1)
11619 && TREE_INT_CST_HIGH (arg1) < 0
11620 && !TYPE_OVERFLOW_TRAPS (type)
11621 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11622 && !sign_bit_p (arg1, arg1))
11623 return fold_build2_loc (loc, code, type,
11624 fold_convert_loc (loc, type, arg0),
11625 fold_convert_loc (loc, type,
11626 negate_expr (arg1)));
11628 /* X % -Y is the same as X % Y. */
11629 if (code == TRUNC_MOD_EXPR
11630 && !TYPE_UNSIGNED (type)
11631 && TREE_CODE (arg1) == NEGATE_EXPR
11632 && !TYPE_OVERFLOW_TRAPS (type))
11633 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
11634 fold_convert_loc (loc, type,
11635 TREE_OPERAND (arg1, 0)));
11637 strict_overflow_p = false;
11638 if (TREE_CODE (arg1) == INTEGER_CST
11639 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11640 &strict_overflow_p)))
11642 if (strict_overflow_p)
11643 fold_overflow_warning (("assuming signed overflow does not occur "
11644 "when simplifying modulus"),
11645 WARN_STRICT_OVERFLOW_MISC);
11646 return fold_convert_loc (loc, type, tem);
11649 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11650 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11651 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11652 && (TYPE_UNSIGNED (type)
11653 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11656 /* Also optimize A % (C << N) where C is a power of 2,
11657 to A & ((C << N) - 1). */
11658 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11659 c = TREE_OPERAND (arg1, 0);
11661 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11664 = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
11665 build_int_cst (TREE_TYPE (arg1), 1));
11666 if (strict_overflow_p)
11667 fold_overflow_warning (("assuming signed overflow does not "
11668 "occur when simplifying "
11669 "X % (power of two)"),
11670 WARN_STRICT_OVERFLOW_MISC);
11671 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11672 fold_convert_loc (loc, type, arg0),
11673 fold_convert_loc (loc, type, mask));
11681 if (integer_all_onesp (arg0))
11682 return omit_one_operand_loc (loc, type, arg0, arg1);
11686 /* Optimize -1 >> x for arithmetic right shifts. */
11687 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11688 && tree_expr_nonnegative_p (arg1))
11689 return omit_one_operand_loc (loc, type, arg0, arg1);
11690 /* ... fall through ... */
11694 if (integer_zerop (arg1))
11695 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11696 if (integer_zerop (arg0))
11697 return omit_one_operand_loc (loc, type, arg0, arg1);
11699 /* Since negative shift count is not well-defined,
11700 don't try to compute it in the compiler. */
11701 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11704 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11705 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11706 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11707 && host_integerp (TREE_OPERAND (arg0, 1), false)
11708 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11710 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11711 + TREE_INT_CST_LOW (arg1));
11713 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11714 being well defined. */
11715 if (low >= TYPE_PRECISION (type))
11717 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11718 low = low % TYPE_PRECISION (type);
11719 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11720 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
11721 TREE_OPERAND (arg0, 0));
11723 low = TYPE_PRECISION (type) - 1;
11726 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
11727 build_int_cst (type, low));
11730 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11731 into x & ((unsigned)-1 >> c) for unsigned types. */
11732 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11733 || (TYPE_UNSIGNED (type)
11734 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11735 && host_integerp (arg1, false)
11736 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11737 && host_integerp (TREE_OPERAND (arg0, 1), false)
11738 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11740 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11741 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11747 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11749 lshift = build_int_cst (type, -1);
11750 lshift = int_const_binop (code, lshift, arg1, 0);
11752 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
11756 /* Rewrite an LROTATE_EXPR by a constant into an
11757 RROTATE_EXPR by a new constant. */
11758 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11760 tree tem = build_int_cst (TREE_TYPE (arg1),
11761 TYPE_PRECISION (type));
11762 tem = const_binop (MINUS_EXPR, tem, arg1);
11763 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
11766 /* If we have a rotate of a bit operation with the rotate count and
11767 the second operand of the bit operation both constant,
11768 permute the two operations. */
11769 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11770 && (TREE_CODE (arg0) == BIT_AND_EXPR
11771 || TREE_CODE (arg0) == BIT_IOR_EXPR
11772 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11773 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11774 return fold_build2_loc (loc, TREE_CODE (arg0), type,
11775 fold_build2_loc (loc, code, type,
11776 TREE_OPERAND (arg0, 0), arg1),
11777 fold_build2_loc (loc, code, type,
11778 TREE_OPERAND (arg0, 1), arg1));
11780 /* Two consecutive rotates adding up to the precision of the
11781 type can be ignored. */
11782 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11783 && TREE_CODE (arg0) == RROTATE_EXPR
11784 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11785 && TREE_INT_CST_HIGH (arg1) == 0
11786 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11787 && ((TREE_INT_CST_LOW (arg1)
11788 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11789 == (unsigned int) TYPE_PRECISION (type)))
11790 return TREE_OPERAND (arg0, 0);
11792 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11793 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11794 if the latter can be further optimized. */
11795 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11796 && TREE_CODE (arg0) == BIT_AND_EXPR
11797 && TREE_CODE (arg1) == INTEGER_CST
11798 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11800 tree mask = fold_build2_loc (loc, code, type,
11801 fold_convert_loc (loc, type,
11802 TREE_OPERAND (arg0, 1)),
11804 tree shift = fold_build2_loc (loc, code, type,
11805 fold_convert_loc (loc, type,
11806 TREE_OPERAND (arg0, 0)),
11808 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
11816 if (operand_equal_p (arg0, arg1, 0))
11817 return omit_one_operand_loc (loc, type, arg0, arg1);
11818 if (INTEGRAL_TYPE_P (type)
11819 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11820 return omit_one_operand_loc (loc, type, arg1, arg0);
11821 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
11827 if (operand_equal_p (arg0, arg1, 0))
11828 return omit_one_operand_loc (loc, type, arg0, arg1);
11829 if (INTEGRAL_TYPE_P (type)
11830 && TYPE_MAX_VALUE (type)
11831 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11832 return omit_one_operand_loc (loc, type, arg1, arg0);
11833 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
11838 case TRUTH_ANDIF_EXPR:
11839 /* Note that the operands of this must be ints
11840 and their values must be 0 or 1.
11841 ("true" is a fixed value perhaps depending on the language.) */
11842 /* If first arg is constant zero, return it. */
11843 if (integer_zerop (arg0))
11844 return fold_convert_loc (loc, type, arg0);
11845 case TRUTH_AND_EXPR:
11846 /* If either arg is constant true, drop it. */
11847 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11848 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
11849 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
11850 /* Preserve sequence points. */
11851 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11852 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11853 /* If second arg is constant zero, result is zero, but first arg
11854 must be evaluated. */
11855 if (integer_zerop (arg1))
11856 return omit_one_operand_loc (loc, type, arg1, arg0);
11857 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11858 case will be handled here. */
11859 if (integer_zerop (arg0))
11860 return omit_one_operand_loc (loc, type, arg0, arg1);
11862 /* !X && X is always false. */
11863 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11864 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11865 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11866 /* X && !X is always false. */
11867 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11868 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11869 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11871 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
11872 means A >= Y && A != MAX, but in this case we know that
11875 if (!TREE_SIDE_EFFECTS (arg0)
11876 && !TREE_SIDE_EFFECTS (arg1))
11878 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
11879 if (tem && !operand_equal_p (tem, arg0, 0))
11880 return fold_build2_loc (loc, code, type, tem, arg1);
11882 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
11883 if (tem && !operand_equal_p (tem, arg1, 0))
11884 return fold_build2_loc (loc, code, type, arg0, tem);
11888 /* We only do these simplifications if we are optimizing. */
11892 /* Check for things like (A || B) && (A || C). We can convert this
11893 to A || (B && C). Note that either operator can be any of the four
11894 truth and/or operations and the transformation will still be
11895 valid. Also note that we only care about order for the
11896 ANDIF and ORIF operators. If B contains side effects, this
11897 might change the truth-value of A. */
11898 if (TREE_CODE (arg0) == TREE_CODE (arg1)
11899 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
11900 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
11901 || TREE_CODE (arg0) == TRUTH_AND_EXPR
11902 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
11903 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
11905 tree a00 = TREE_OPERAND (arg0, 0);
11906 tree a01 = TREE_OPERAND (arg0, 1);
11907 tree a10 = TREE_OPERAND (arg1, 0);
11908 tree a11 = TREE_OPERAND (arg1, 1);
11909 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
11910 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
11911 && (code == TRUTH_AND_EXPR
11912 || code == TRUTH_OR_EXPR));
11914 if (operand_equal_p (a00, a10, 0))
11915 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
11916 fold_build2_loc (loc, code, type, a01, a11));
11917 else if (commutative && operand_equal_p (a00, a11, 0))
11918 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
11919 fold_build2_loc (loc, code, type, a01, a10));
11920 else if (commutative && operand_equal_p (a01, a10, 0))
11921 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
11922 fold_build2_loc (loc, code, type, a00, a11));
11924 /* This case if tricky because we must either have commutative
11925 operators or else A10 must not have side-effects. */
11927 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
11928 && operand_equal_p (a01, a11, 0))
11929 return fold_build2_loc (loc, TREE_CODE (arg0), type,
11930 fold_build2_loc (loc, code, type, a00, a10),
11934 /* See if we can build a range comparison. */
11935 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
11938 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg0) == TRUTH_ORIF_EXPR)
11939 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg0) == TRUTH_ANDIF_EXPR))
11941 tem = merge_truthop_with_opposite_arm (loc, arg0, arg1, true);
11943 return fold_build2_loc (loc, code, type, tem, arg1);
11946 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg1) == TRUTH_ORIF_EXPR)
11947 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg1) == TRUTH_ANDIF_EXPR))
11949 tem = merge_truthop_with_opposite_arm (loc, arg1, arg0, false);
11951 return fold_build2_loc (loc, code, type, arg0, tem);
11954 /* Check for the possibility of merging component references. If our
11955 lhs is another similar operation, try to merge its rhs with our
11956 rhs. Then try to merge our lhs and rhs. */
11957 if (TREE_CODE (arg0) == code
11958 && 0 != (tem = fold_truthop (loc, code, type,
11959 TREE_OPERAND (arg0, 1), arg1)))
11960 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
11962 if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
11967 case TRUTH_ORIF_EXPR:
11968 /* Note that the operands of this must be ints
11969 and their values must be 0 or true.
11970 ("true" is a fixed value perhaps depending on the language.) */
11971 /* If first arg is constant true, return it. */
11972 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11973 return fold_convert_loc (loc, type, arg0);
11974 case TRUTH_OR_EXPR:
11975 /* If either arg is constant zero, drop it. */
11976 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
11977 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
11978 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
11979 /* Preserve sequence points. */
11980 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11981 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11982 /* If second arg is constant true, result is true, but we must
11983 evaluate first arg. */
11984 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
11985 return omit_one_operand_loc (loc, type, arg1, arg0);
11986 /* Likewise for first arg, but note this only occurs here for
11988 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11989 return omit_one_operand_loc (loc, type, arg0, arg1);
11991 /* !X || X is always true. */
11992 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11993 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11994 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
11995 /* X || !X is always true. */
11996 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11997 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11998 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12002 case TRUTH_XOR_EXPR:
12003 /* If the second arg is constant zero, drop it. */
12004 if (integer_zerop (arg1))
12005 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12006 /* If the second arg is constant true, this is a logical inversion. */
12007 if (integer_onep (arg1))
12009 /* Only call invert_truthvalue if operand is a truth value. */
12010 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12011 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12013 tem = invert_truthvalue_loc (loc, arg0);
12014 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12016 /* Identical arguments cancel to zero. */
12017 if (operand_equal_p (arg0, arg1, 0))
12018 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12020 /* !X ^ X is always true. */
12021 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12022 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12023 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12025 /* X ^ !X is always true. */
12026 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12027 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12028 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12034 tem = fold_comparison (loc, code, type, op0, op1);
12035 if (tem != NULL_TREE)
12038 /* bool_var != 0 becomes bool_var. */
12039 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12040 && code == NE_EXPR)
12041 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12043 /* bool_var == 1 becomes bool_var. */
12044 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12045 && code == EQ_EXPR)
12046 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12048 /* bool_var != 1 becomes !bool_var. */
12049 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12050 && code == NE_EXPR)
12051 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12052 fold_convert_loc (loc, type, arg0));
12054 /* bool_var == 0 becomes !bool_var. */
12055 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12056 && code == EQ_EXPR)
12057 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12058 fold_convert_loc (loc, type, arg0));
12060 /* !exp != 0 becomes !exp */
12061 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12062 && code == NE_EXPR)
12063 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12065 /* If this is an equality comparison of the address of two non-weak,
12066 unaliased symbols neither of which are extern (since we do not
12067 have access to attributes for externs), then we know the result. */
12068 if (TREE_CODE (arg0) == ADDR_EXPR
12069 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12070 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12071 && ! lookup_attribute ("alias",
12072 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12073 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12074 && TREE_CODE (arg1) == ADDR_EXPR
12075 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12076 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12077 && ! lookup_attribute ("alias",
12078 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12079 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12081 /* We know that we're looking at the address of two
12082 non-weak, unaliased, static _DECL nodes.
12084 It is both wasteful and incorrect to call operand_equal_p
12085 to compare the two ADDR_EXPR nodes. It is wasteful in that
12086 all we need to do is test pointer equality for the arguments
12087 to the two ADDR_EXPR nodes. It is incorrect to use
12088 operand_equal_p as that function is NOT equivalent to a
12089 C equality test. It can in fact return false for two
12090 objects which would test as equal using the C equality
12092 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12093 return constant_boolean_node (equal
12094 ? code == EQ_EXPR : code != EQ_EXPR,
12098 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12099 a MINUS_EXPR of a constant, we can convert it into a comparison with
12100 a revised constant as long as no overflow occurs. */
12101 if (TREE_CODE (arg1) == INTEGER_CST
12102 && (TREE_CODE (arg0) == PLUS_EXPR
12103 || TREE_CODE (arg0) == MINUS_EXPR)
12104 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12105 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12106 ? MINUS_EXPR : PLUS_EXPR,
12107 fold_convert_loc (loc, TREE_TYPE (arg0),
12109 TREE_OPERAND (arg0, 1)))
12110 && !TREE_OVERFLOW (tem))
12111 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12113 /* Similarly for a NEGATE_EXPR. */
12114 if (TREE_CODE (arg0) == NEGATE_EXPR
12115 && TREE_CODE (arg1) == INTEGER_CST
12116 && 0 != (tem = negate_expr (arg1))
12117 && TREE_CODE (tem) == INTEGER_CST
12118 && !TREE_OVERFLOW (tem))
12119 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12121 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12122 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12123 && TREE_CODE (arg1) == INTEGER_CST
12124 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12125 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12126 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12127 fold_convert_loc (loc,
12130 TREE_OPERAND (arg0, 1)));
12132 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12133 if ((TREE_CODE (arg0) == PLUS_EXPR
12134 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12135 || TREE_CODE (arg0) == MINUS_EXPR)
12136 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12137 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12138 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12140 tree val = TREE_OPERAND (arg0, 1);
12141 return omit_two_operands_loc (loc, type,
12142 fold_build2_loc (loc, code, type,
12144 build_int_cst (TREE_TYPE (val),
12146 TREE_OPERAND (arg0, 0), arg1);
12149 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12150 if (TREE_CODE (arg0) == MINUS_EXPR
12151 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12152 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
12153 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12155 return omit_two_operands_loc (loc, type,
12157 ? boolean_true_node : boolean_false_node,
12158 TREE_OPERAND (arg0, 1), arg1);
12161 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12162 for !=. Don't do this for ordered comparisons due to overflow. */
12163 if (TREE_CODE (arg0) == MINUS_EXPR
12164 && integer_zerop (arg1))
12165 return fold_build2_loc (loc, code, type,
12166 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12168 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12169 if (TREE_CODE (arg0) == ABS_EXPR
12170 && (integer_zerop (arg1) || real_zerop (arg1)))
12171 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12173 /* If this is an EQ or NE comparison with zero and ARG0 is
12174 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12175 two operations, but the latter can be done in one less insn
12176 on machines that have only two-operand insns or on which a
12177 constant cannot be the first operand. */
12178 if (TREE_CODE (arg0) == BIT_AND_EXPR
12179 && integer_zerop (arg1))
12181 tree arg00 = TREE_OPERAND (arg0, 0);
12182 tree arg01 = TREE_OPERAND (arg0, 1);
12183 if (TREE_CODE (arg00) == LSHIFT_EXPR
12184 && integer_onep (TREE_OPERAND (arg00, 0)))
12186 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12187 arg01, TREE_OPERAND (arg00, 1));
12188 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12189 build_int_cst (TREE_TYPE (arg0), 1));
12190 return fold_build2_loc (loc, code, type,
12191 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12194 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12195 && integer_onep (TREE_OPERAND (arg01, 0)))
12197 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12198 arg00, TREE_OPERAND (arg01, 1));
12199 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12200 build_int_cst (TREE_TYPE (arg0), 1));
12201 return fold_build2_loc (loc, code, type,
12202 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12207 /* If this is an NE or EQ comparison of zero against the result of a
12208 signed MOD operation whose second operand is a power of 2, make
12209 the MOD operation unsigned since it is simpler and equivalent. */
12210 if (integer_zerop (arg1)
12211 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12212 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12213 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12214 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12215 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12216 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12218 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12219 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12220 fold_convert_loc (loc, newtype,
12221 TREE_OPERAND (arg0, 0)),
12222 fold_convert_loc (loc, newtype,
12223 TREE_OPERAND (arg0, 1)));
12225 return fold_build2_loc (loc, code, type, newmod,
12226 fold_convert_loc (loc, newtype, arg1));
12229 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12230 C1 is a valid shift constant, and C2 is a power of two, i.e.
12232 if (TREE_CODE (arg0) == BIT_AND_EXPR
12233 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12234 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12236 && integer_pow2p (TREE_OPERAND (arg0, 1))
12237 && integer_zerop (arg1))
12239 tree itype = TREE_TYPE (arg0);
12240 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12241 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12243 /* Check for a valid shift count. */
12244 if (TREE_INT_CST_HIGH (arg001) == 0
12245 && TREE_INT_CST_LOW (arg001) < prec)
12247 tree arg01 = TREE_OPERAND (arg0, 1);
12248 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12249 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12250 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12251 can be rewritten as (X & (C2 << C1)) != 0. */
12252 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12254 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12255 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12256 return fold_build2_loc (loc, code, type, tem, arg1);
12258 /* Otherwise, for signed (arithmetic) shifts,
12259 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12260 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12261 else if (!TYPE_UNSIGNED (itype))
12262 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12263 arg000, build_int_cst (itype, 0));
12264 /* Otherwise, of unsigned (logical) shifts,
12265 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12266 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12268 return omit_one_operand_loc (loc, type,
12269 code == EQ_EXPR ? integer_one_node
12270 : integer_zero_node,
12275 /* If this is an NE comparison of zero with an AND of one, remove the
12276 comparison since the AND will give the correct value. */
12277 if (code == NE_EXPR
12278 && integer_zerop (arg1)
12279 && TREE_CODE (arg0) == BIT_AND_EXPR
12280 && integer_onep (TREE_OPERAND (arg0, 1)))
12281 return fold_convert_loc (loc, type, arg0);
12283 /* If we have (A & C) == C where C is a power of 2, convert this into
12284 (A & C) != 0. Similarly for NE_EXPR. */
12285 if (TREE_CODE (arg0) == BIT_AND_EXPR
12286 && integer_pow2p (TREE_OPERAND (arg0, 1))
12287 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12288 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12289 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12290 integer_zero_node));
12292 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12293 bit, then fold the expression into A < 0 or A >= 0. */
12294 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12298 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12299 Similarly for NE_EXPR. */
12300 if (TREE_CODE (arg0) == BIT_AND_EXPR
12301 && TREE_CODE (arg1) == INTEGER_CST
12302 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12304 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12305 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12306 TREE_OPERAND (arg0, 1));
12307 tree dandnotc = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12309 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12310 if (integer_nonzerop (dandnotc))
12311 return omit_one_operand_loc (loc, type, rslt, arg0);
12314 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12315 Similarly for NE_EXPR. */
12316 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12317 && TREE_CODE (arg1) == INTEGER_CST
12318 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12320 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12321 tree candnotd = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12322 TREE_OPERAND (arg0, 1), notd);
12323 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12324 if (integer_nonzerop (candnotd))
12325 return omit_one_operand_loc (loc, type, rslt, arg0);
12328 /* If this is a comparison of a field, we may be able to simplify it. */
12329 if ((TREE_CODE (arg0) == COMPONENT_REF
12330 || TREE_CODE (arg0) == BIT_FIELD_REF)
12331 /* Handle the constant case even without -O
12332 to make sure the warnings are given. */
12333 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12335 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12340 /* Optimize comparisons of strlen vs zero to a compare of the
12341 first character of the string vs zero. To wit,
12342 strlen(ptr) == 0 => *ptr == 0
12343 strlen(ptr) != 0 => *ptr != 0
12344 Other cases should reduce to one of these two (or a constant)
12345 due to the return value of strlen being unsigned. */
12346 if (TREE_CODE (arg0) == CALL_EXPR
12347 && integer_zerop (arg1))
12349 tree fndecl = get_callee_fndecl (arg0);
12352 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12353 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12354 && call_expr_nargs (arg0) == 1
12355 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12357 tree iref = build_fold_indirect_ref_loc (loc,
12358 CALL_EXPR_ARG (arg0, 0));
12359 return fold_build2_loc (loc, code, type, iref,
12360 build_int_cst (TREE_TYPE (iref), 0));
12364 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12365 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12366 if (TREE_CODE (arg0) == RSHIFT_EXPR
12367 && integer_zerop (arg1)
12368 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12370 tree arg00 = TREE_OPERAND (arg0, 0);
12371 tree arg01 = TREE_OPERAND (arg0, 1);
12372 tree itype = TREE_TYPE (arg00);
12373 if (TREE_INT_CST_HIGH (arg01) == 0
12374 && TREE_INT_CST_LOW (arg01)
12375 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12377 if (TYPE_UNSIGNED (itype))
12379 itype = signed_type_for (itype);
12380 arg00 = fold_convert_loc (loc, itype, arg00);
12382 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12383 type, arg00, build_int_cst (itype, 0));
12387 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12388 if (integer_zerop (arg1)
12389 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12390 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12391 TREE_OPERAND (arg0, 1));
12393 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12394 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12395 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12396 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12397 build_int_cst (TREE_TYPE (arg1), 0));
12398 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12399 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12400 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12401 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12402 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12403 build_int_cst (TREE_TYPE (arg1), 0));
12405 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12406 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12407 && TREE_CODE (arg1) == INTEGER_CST
12408 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12409 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12410 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12411 TREE_OPERAND (arg0, 1), arg1));
12413 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12414 (X & C) == 0 when C is a single bit. */
12415 if (TREE_CODE (arg0) == BIT_AND_EXPR
12416 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12417 && integer_zerop (arg1)
12418 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12420 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12421 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12422 TREE_OPERAND (arg0, 1));
12423 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12427 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12428 constant C is a power of two, i.e. a single bit. */
12429 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12430 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12431 && integer_zerop (arg1)
12432 && integer_pow2p (TREE_OPERAND (arg0, 1))
12433 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12434 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12436 tree arg00 = TREE_OPERAND (arg0, 0);
12437 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12438 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12441 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12442 when is C is a power of two, i.e. a single bit. */
12443 if (TREE_CODE (arg0) == BIT_AND_EXPR
12444 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12445 && integer_zerop (arg1)
12446 && integer_pow2p (TREE_OPERAND (arg0, 1))
12447 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12448 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12450 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12451 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
12452 arg000, TREE_OPERAND (arg0, 1));
12453 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12454 tem, build_int_cst (TREE_TYPE (tem), 0));
12457 if (integer_zerop (arg1)
12458 && tree_expr_nonzero_p (arg0))
12460 tree res = constant_boolean_node (code==NE_EXPR, type);
12461 return omit_one_operand_loc (loc, type, res, arg0);
12464 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12465 if (TREE_CODE (arg0) == NEGATE_EXPR
12466 && TREE_CODE (arg1) == NEGATE_EXPR)
12467 return fold_build2_loc (loc, code, type,
12468 TREE_OPERAND (arg0, 0),
12469 TREE_OPERAND (arg1, 0));
12471 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12472 if (TREE_CODE (arg0) == BIT_AND_EXPR
12473 && TREE_CODE (arg1) == BIT_AND_EXPR)
12475 tree arg00 = TREE_OPERAND (arg0, 0);
12476 tree arg01 = TREE_OPERAND (arg0, 1);
12477 tree arg10 = TREE_OPERAND (arg1, 0);
12478 tree arg11 = TREE_OPERAND (arg1, 1);
12479 tree itype = TREE_TYPE (arg0);
12481 if (operand_equal_p (arg01, arg11, 0))
12482 return fold_build2_loc (loc, code, type,
12483 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12484 fold_build2_loc (loc,
12485 BIT_XOR_EXPR, itype,
12488 build_int_cst (itype, 0));
12490 if (operand_equal_p (arg01, arg10, 0))
12491 return fold_build2_loc (loc, code, type,
12492 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12493 fold_build2_loc (loc,
12494 BIT_XOR_EXPR, itype,
12497 build_int_cst (itype, 0));
12499 if (operand_equal_p (arg00, arg11, 0))
12500 return fold_build2_loc (loc, code, type,
12501 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12502 fold_build2_loc (loc,
12503 BIT_XOR_EXPR, itype,
12506 build_int_cst (itype, 0));
12508 if (operand_equal_p (arg00, arg10, 0))
12509 return fold_build2_loc (loc, code, type,
12510 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12511 fold_build2_loc (loc,
12512 BIT_XOR_EXPR, itype,
12515 build_int_cst (itype, 0));
12518 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12519 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12521 tree arg00 = TREE_OPERAND (arg0, 0);
12522 tree arg01 = TREE_OPERAND (arg0, 1);
12523 tree arg10 = TREE_OPERAND (arg1, 0);
12524 tree arg11 = TREE_OPERAND (arg1, 1);
12525 tree itype = TREE_TYPE (arg0);
12527 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12528 operand_equal_p guarantees no side-effects so we don't need
12529 to use omit_one_operand on Z. */
12530 if (operand_equal_p (arg01, arg11, 0))
12531 return fold_build2_loc (loc, code, type, arg00, arg10);
12532 if (operand_equal_p (arg01, arg10, 0))
12533 return fold_build2_loc (loc, code, type, arg00, arg11);
12534 if (operand_equal_p (arg00, arg11, 0))
12535 return fold_build2_loc (loc, code, type, arg01, arg10);
12536 if (operand_equal_p (arg00, arg10, 0))
12537 return fold_build2_loc (loc, code, type, arg01, arg11);
12539 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12540 if (TREE_CODE (arg01) == INTEGER_CST
12541 && TREE_CODE (arg11) == INTEGER_CST)
12542 return fold_build2_loc (loc, code, type,
12543 fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00,
12544 fold_build2_loc (loc,
12545 BIT_XOR_EXPR, itype,
12550 /* Attempt to simplify equality/inequality comparisons of complex
12551 values. Only lower the comparison if the result is known or
12552 can be simplified to a single scalar comparison. */
12553 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12554 || TREE_CODE (arg0) == COMPLEX_CST)
12555 && (TREE_CODE (arg1) == COMPLEX_EXPR
12556 || TREE_CODE (arg1) == COMPLEX_CST))
12558 tree real0, imag0, real1, imag1;
12561 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12563 real0 = TREE_OPERAND (arg0, 0);
12564 imag0 = TREE_OPERAND (arg0, 1);
12568 real0 = TREE_REALPART (arg0);
12569 imag0 = TREE_IMAGPART (arg0);
12572 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12574 real1 = TREE_OPERAND (arg1, 0);
12575 imag1 = TREE_OPERAND (arg1, 1);
12579 real1 = TREE_REALPART (arg1);
12580 imag1 = TREE_IMAGPART (arg1);
12583 rcond = fold_binary_loc (loc, code, type, real0, real1);
12584 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12586 if (integer_zerop (rcond))
12588 if (code == EQ_EXPR)
12589 return omit_two_operands_loc (loc, type, boolean_false_node,
12591 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
12595 if (code == NE_EXPR)
12596 return omit_two_operands_loc (loc, type, boolean_true_node,
12598 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
12602 icond = fold_binary_loc (loc, code, type, imag0, imag1);
12603 if (icond && TREE_CODE (icond) == INTEGER_CST)
12605 if (integer_zerop (icond))
12607 if (code == EQ_EXPR)
12608 return omit_two_operands_loc (loc, type, boolean_false_node,
12610 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
12614 if (code == NE_EXPR)
12615 return omit_two_operands_loc (loc, type, boolean_true_node,
12617 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
12628 tem = fold_comparison (loc, code, type, op0, op1);
12629 if (tem != NULL_TREE)
12632 /* Transform comparisons of the form X +- C CMP X. */
12633 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12634 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12635 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12636 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12637 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12638 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12640 tree arg01 = TREE_OPERAND (arg0, 1);
12641 enum tree_code code0 = TREE_CODE (arg0);
12644 if (TREE_CODE (arg01) == REAL_CST)
12645 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12647 is_positive = tree_int_cst_sgn (arg01);
12649 /* (X - c) > X becomes false. */
12650 if (code == GT_EXPR
12651 && ((code0 == MINUS_EXPR && is_positive >= 0)
12652 || (code0 == PLUS_EXPR && is_positive <= 0)))
12654 if (TREE_CODE (arg01) == INTEGER_CST
12655 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12656 fold_overflow_warning (("assuming signed overflow does not "
12657 "occur when assuming that (X - c) > X "
12658 "is always false"),
12659 WARN_STRICT_OVERFLOW_ALL);
12660 return constant_boolean_node (0, type);
12663 /* Likewise (X + c) < X becomes false. */
12664 if (code == LT_EXPR
12665 && ((code0 == PLUS_EXPR && is_positive >= 0)
12666 || (code0 == MINUS_EXPR && is_positive <= 0)))
12668 if (TREE_CODE (arg01) == INTEGER_CST
12669 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12670 fold_overflow_warning (("assuming signed overflow does not "
12671 "occur when assuming that "
12672 "(X + c) < X is always false"),
12673 WARN_STRICT_OVERFLOW_ALL);
12674 return constant_boolean_node (0, type);
12677 /* Convert (X - c) <= X to true. */
12678 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12680 && ((code0 == MINUS_EXPR && is_positive >= 0)
12681 || (code0 == PLUS_EXPR && is_positive <= 0)))
12683 if (TREE_CODE (arg01) == INTEGER_CST
12684 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12685 fold_overflow_warning (("assuming signed overflow does not "
12686 "occur when assuming that "
12687 "(X - c) <= X is always true"),
12688 WARN_STRICT_OVERFLOW_ALL);
12689 return constant_boolean_node (1, type);
12692 /* Convert (X + c) >= X to true. */
12693 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12695 && ((code0 == PLUS_EXPR && is_positive >= 0)
12696 || (code0 == MINUS_EXPR && is_positive <= 0)))
12698 if (TREE_CODE (arg01) == INTEGER_CST
12699 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12700 fold_overflow_warning (("assuming signed overflow does not "
12701 "occur when assuming that "
12702 "(X + c) >= X is always true"),
12703 WARN_STRICT_OVERFLOW_ALL);
12704 return constant_boolean_node (1, type);
12707 if (TREE_CODE (arg01) == INTEGER_CST)
12709 /* Convert X + c > X and X - c < X to true for integers. */
12710 if (code == GT_EXPR
12711 && ((code0 == PLUS_EXPR && is_positive > 0)
12712 || (code0 == MINUS_EXPR && is_positive < 0)))
12714 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12715 fold_overflow_warning (("assuming signed overflow does "
12716 "not occur when assuming that "
12717 "(X + c) > X is always true"),
12718 WARN_STRICT_OVERFLOW_ALL);
12719 return constant_boolean_node (1, type);
12722 if (code == LT_EXPR
12723 && ((code0 == MINUS_EXPR && is_positive > 0)
12724 || (code0 == PLUS_EXPR && is_positive < 0)))
12726 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12727 fold_overflow_warning (("assuming signed overflow does "
12728 "not occur when assuming that "
12729 "(X - c) < X is always true"),
12730 WARN_STRICT_OVERFLOW_ALL);
12731 return constant_boolean_node (1, type);
12734 /* Convert X + c <= X and X - c >= X to false for integers. */
12735 if (code == LE_EXPR
12736 && ((code0 == PLUS_EXPR && is_positive > 0)
12737 || (code0 == MINUS_EXPR && is_positive < 0)))
12739 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12740 fold_overflow_warning (("assuming signed overflow does "
12741 "not occur when assuming that "
12742 "(X + c) <= X is always false"),
12743 WARN_STRICT_OVERFLOW_ALL);
12744 return constant_boolean_node (0, type);
12747 if (code == GE_EXPR
12748 && ((code0 == MINUS_EXPR && is_positive > 0)
12749 || (code0 == PLUS_EXPR && is_positive < 0)))
12751 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12752 fold_overflow_warning (("assuming signed overflow does "
12753 "not occur when assuming that "
12754 "(X - c) >= X is always false"),
12755 WARN_STRICT_OVERFLOW_ALL);
12756 return constant_boolean_node (0, type);
12761 /* Comparisons with the highest or lowest possible integer of
12762 the specified precision will have known values. */
12764 tree arg1_type = TREE_TYPE (arg1);
12765 unsigned int width = TYPE_PRECISION (arg1_type);
12767 if (TREE_CODE (arg1) == INTEGER_CST
12768 && width <= 2 * HOST_BITS_PER_WIDE_INT
12769 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12771 HOST_WIDE_INT signed_max_hi;
12772 unsigned HOST_WIDE_INT signed_max_lo;
12773 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12775 if (width <= HOST_BITS_PER_WIDE_INT)
12777 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12782 if (TYPE_UNSIGNED (arg1_type))
12784 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12790 max_lo = signed_max_lo;
12791 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12797 width -= HOST_BITS_PER_WIDE_INT;
12798 signed_max_lo = -1;
12799 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12804 if (TYPE_UNSIGNED (arg1_type))
12806 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12811 max_hi = signed_max_hi;
12812 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12816 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12817 && TREE_INT_CST_LOW (arg1) == max_lo)
12821 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12824 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12827 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12830 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
12832 /* The GE_EXPR and LT_EXPR cases above are not normally
12833 reached because of previous transformations. */
12838 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12840 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12844 arg1 = const_binop (PLUS_EXPR, arg1,
12845 build_int_cst (TREE_TYPE (arg1), 1));
12846 return fold_build2_loc (loc, EQ_EXPR, type,
12847 fold_convert_loc (loc,
12848 TREE_TYPE (arg1), arg0),
12851 arg1 = const_binop (PLUS_EXPR, arg1,
12852 build_int_cst (TREE_TYPE (arg1), 1));
12853 return fold_build2_loc (loc, NE_EXPR, type,
12854 fold_convert_loc (loc, TREE_TYPE (arg1),
12860 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12862 && TREE_INT_CST_LOW (arg1) == min_lo)
12866 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12869 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12872 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12875 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
12880 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12882 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
12886 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
12887 return fold_build2_loc (loc, NE_EXPR, type,
12888 fold_convert_loc (loc,
12889 TREE_TYPE (arg1), arg0),
12892 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
12893 return fold_build2_loc (loc, EQ_EXPR, type,
12894 fold_convert_loc (loc, TREE_TYPE (arg1),
12901 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
12902 && TREE_INT_CST_LOW (arg1) == signed_max_lo
12903 && TYPE_UNSIGNED (arg1_type)
12904 /* We will flip the signedness of the comparison operator
12905 associated with the mode of arg1, so the sign bit is
12906 specified by this mode. Check that arg1 is the signed
12907 max associated with this sign bit. */
12908 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
12909 /* signed_type does not work on pointer types. */
12910 && INTEGRAL_TYPE_P (arg1_type))
12912 /* The following case also applies to X < signed_max+1
12913 and X >= signed_max+1 because previous transformations. */
12914 if (code == LE_EXPR || code == GT_EXPR)
12917 st = signed_type_for (TREE_TYPE (arg1));
12918 return fold_build2_loc (loc,
12919 code == LE_EXPR ? GE_EXPR : LT_EXPR,
12920 type, fold_convert_loc (loc, st, arg0),
12921 build_int_cst (st, 0));
12927 /* If we are comparing an ABS_EXPR with a constant, we can
12928 convert all the cases into explicit comparisons, but they may
12929 well not be faster than doing the ABS and one comparison.
12930 But ABS (X) <= C is a range comparison, which becomes a subtraction
12931 and a comparison, and is probably faster. */
12932 if (code == LE_EXPR
12933 && TREE_CODE (arg1) == INTEGER_CST
12934 && TREE_CODE (arg0) == ABS_EXPR
12935 && ! TREE_SIDE_EFFECTS (arg0)
12936 && (0 != (tem = negate_expr (arg1)))
12937 && TREE_CODE (tem) == INTEGER_CST
12938 && !TREE_OVERFLOW (tem))
12939 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
12940 build2 (GE_EXPR, type,
12941 TREE_OPERAND (arg0, 0), tem),
12942 build2 (LE_EXPR, type,
12943 TREE_OPERAND (arg0, 0), arg1));
12945 /* Convert ABS_EXPR<x> >= 0 to true. */
12946 strict_overflow_p = false;
12947 if (code == GE_EXPR
12948 && (integer_zerop (arg1)
12949 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
12950 && real_zerop (arg1)))
12951 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
12953 if (strict_overflow_p)
12954 fold_overflow_warning (("assuming signed overflow does not occur "
12955 "when simplifying comparison of "
12956 "absolute value and zero"),
12957 WARN_STRICT_OVERFLOW_CONDITIONAL);
12958 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12961 /* Convert ABS_EXPR<x> < 0 to false. */
12962 strict_overflow_p = false;
12963 if (code == LT_EXPR
12964 && (integer_zerop (arg1) || real_zerop (arg1))
12965 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
12967 if (strict_overflow_p)
12968 fold_overflow_warning (("assuming signed overflow does not occur "
12969 "when simplifying comparison of "
12970 "absolute value and zero"),
12971 WARN_STRICT_OVERFLOW_CONDITIONAL);
12972 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12975 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
12976 and similarly for >= into !=. */
12977 if ((code == LT_EXPR || code == GE_EXPR)
12978 && TYPE_UNSIGNED (TREE_TYPE (arg0))
12979 && TREE_CODE (arg1) == LSHIFT_EXPR
12980 && integer_onep (TREE_OPERAND (arg1, 0)))
12982 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
12983 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
12984 TREE_OPERAND (arg1, 1)),
12985 build_int_cst (TREE_TYPE (arg0), 0));
12986 goto fold_binary_exit;
12989 if ((code == LT_EXPR || code == GE_EXPR)
12990 && TYPE_UNSIGNED (TREE_TYPE (arg0))
12991 && CONVERT_EXPR_P (arg1)
12992 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
12993 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
12995 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
12996 fold_convert_loc (loc, TREE_TYPE (arg0),
12997 build2 (RSHIFT_EXPR,
12998 TREE_TYPE (arg0), arg0,
12999 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13001 build_int_cst (TREE_TYPE (arg0), 0));
13002 goto fold_binary_exit;
13007 case UNORDERED_EXPR:
13015 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13017 t1 = fold_relational_const (code, type, arg0, arg1);
13018 if (t1 != NULL_TREE)
13022 /* If the first operand is NaN, the result is constant. */
13023 if (TREE_CODE (arg0) == REAL_CST
13024 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13025 && (code != LTGT_EXPR || ! flag_trapping_math))
13027 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13028 ? integer_zero_node
13029 : integer_one_node;
13030 return omit_one_operand_loc (loc, type, t1, arg1);
13033 /* If the second operand is NaN, the result is constant. */
13034 if (TREE_CODE (arg1) == REAL_CST
13035 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13036 && (code != LTGT_EXPR || ! flag_trapping_math))
13038 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13039 ? integer_zero_node
13040 : integer_one_node;
13041 return omit_one_operand_loc (loc, type, t1, arg0);
13044 /* Simplify unordered comparison of something with itself. */
13045 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13046 && operand_equal_p (arg0, arg1, 0))
13047 return constant_boolean_node (1, type);
13049 if (code == LTGT_EXPR
13050 && !flag_trapping_math
13051 && operand_equal_p (arg0, arg1, 0))
13052 return constant_boolean_node (0, type);
13054 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13056 tree targ0 = strip_float_extensions (arg0);
13057 tree targ1 = strip_float_extensions (arg1);
13058 tree newtype = TREE_TYPE (targ0);
13060 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13061 newtype = TREE_TYPE (targ1);
13063 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13064 return fold_build2_loc (loc, code, type,
13065 fold_convert_loc (loc, newtype, targ0),
13066 fold_convert_loc (loc, newtype, targ1));
13071 case COMPOUND_EXPR:
13072 /* When pedantic, a compound expression can be neither an lvalue
13073 nor an integer constant expression. */
13074 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13076 /* Don't let (0, 0) be null pointer constant. */
13077 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13078 : fold_convert_loc (loc, type, arg1);
13079 return pedantic_non_lvalue_loc (loc, tem);
13082 if ((TREE_CODE (arg0) == REAL_CST
13083 && TREE_CODE (arg1) == REAL_CST)
13084 || (TREE_CODE (arg0) == INTEGER_CST
13085 && TREE_CODE (arg1) == INTEGER_CST))
13086 return build_complex (type, arg0, arg1);
13090 /* An ASSERT_EXPR should never be passed to fold_binary. */
13091 gcc_unreachable ();
13095 } /* switch (code) */
13097 protected_set_expr_location (tem, loc);
13101 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13102 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13106 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13108 switch (TREE_CODE (*tp))
13114 *walk_subtrees = 0;
13116 /* ... fall through ... */
13123 /* Return whether the sub-tree ST contains a label which is accessible from
13124 outside the sub-tree. */
13127 contains_label_p (tree st)
13130 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13133 /* Fold a ternary expression of code CODE and type TYPE with operands
13134 OP0, OP1, and OP2. Return the folded expression if folding is
13135 successful. Otherwise, return NULL_TREE. */
13138 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13139 tree op0, tree op1, tree op2)
13142 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13143 enum tree_code_class kind = TREE_CODE_CLASS (code);
13145 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13146 && TREE_CODE_LENGTH (code) == 3);
13148 /* Strip any conversions that don't change the mode. This is safe
13149 for every expression, except for a comparison expression because
13150 its signedness is derived from its operands. So, in the latter
13151 case, only strip conversions that don't change the signedness.
13153 Note that this is done as an internal manipulation within the
13154 constant folder, in order to find the simplest representation of
13155 the arguments so that their form can be studied. In any cases,
13156 the appropriate type conversions should be put back in the tree
13157 that will get out of the constant folder. */
13172 case COMPONENT_REF:
13173 if (TREE_CODE (arg0) == CONSTRUCTOR
13174 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13176 unsigned HOST_WIDE_INT idx;
13178 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13185 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13186 so all simple results must be passed through pedantic_non_lvalue. */
13187 if (TREE_CODE (arg0) == INTEGER_CST)
13189 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13190 tem = integer_zerop (arg0) ? op2 : op1;
13191 /* Only optimize constant conditions when the selected branch
13192 has the same type as the COND_EXPR. This avoids optimizing
13193 away "c ? x : throw", where the throw has a void type.
13194 Avoid throwing away that operand which contains label. */
13195 if ((!TREE_SIDE_EFFECTS (unused_op)
13196 || !contains_label_p (unused_op))
13197 && (! VOID_TYPE_P (TREE_TYPE (tem))
13198 || VOID_TYPE_P (type)))
13199 return pedantic_non_lvalue_loc (loc, tem);
13202 if (operand_equal_p (arg1, op2, 0))
13203 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13205 /* If we have A op B ? A : C, we may be able to convert this to a
13206 simpler expression, depending on the operation and the values
13207 of B and C. Signed zeros prevent all of these transformations,
13208 for reasons given above each one.
13210 Also try swapping the arguments and inverting the conditional. */
13211 if (COMPARISON_CLASS_P (arg0)
13212 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13213 arg1, TREE_OPERAND (arg0, 1))
13214 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13216 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13221 if (COMPARISON_CLASS_P (arg0)
13222 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13224 TREE_OPERAND (arg0, 1))
13225 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13227 tem = fold_truth_not_expr (loc, arg0);
13228 if (tem && COMPARISON_CLASS_P (tem))
13230 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13236 /* If the second operand is simpler than the third, swap them
13237 since that produces better jump optimization results. */
13238 if (truth_value_p (TREE_CODE (arg0))
13239 && tree_swap_operands_p (op1, op2, false))
13241 /* See if this can be inverted. If it can't, possibly because
13242 it was a floating-point inequality comparison, don't do
13244 tem = fold_truth_not_expr (loc, arg0);
13246 return fold_build3_loc (loc, code, type, tem, op2, op1);
13249 /* Convert A ? 1 : 0 to simply A. */
13250 if (integer_onep (op1)
13251 && integer_zerop (op2)
13252 /* If we try to convert OP0 to our type, the
13253 call to fold will try to move the conversion inside
13254 a COND, which will recurse. In that case, the COND_EXPR
13255 is probably the best choice, so leave it alone. */
13256 && type == TREE_TYPE (arg0))
13257 return pedantic_non_lvalue_loc (loc, arg0);
13259 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13260 over COND_EXPR in cases such as floating point comparisons. */
13261 if (integer_zerop (op1)
13262 && integer_onep (op2)
13263 && truth_value_p (TREE_CODE (arg0)))
13264 return pedantic_non_lvalue_loc (loc,
13265 fold_convert_loc (loc, type,
13266 invert_truthvalue_loc (loc,
13269 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13270 if (TREE_CODE (arg0) == LT_EXPR
13271 && integer_zerop (TREE_OPERAND (arg0, 1))
13272 && integer_zerop (op2)
13273 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13275 /* sign_bit_p only checks ARG1 bits within A's precision.
13276 If <sign bit of A> has wider type than A, bits outside
13277 of A's precision in <sign bit of A> need to be checked.
13278 If they are all 0, this optimization needs to be done
13279 in unsigned A's type, if they are all 1 in signed A's type,
13280 otherwise this can't be done. */
13281 if (TYPE_PRECISION (TREE_TYPE (tem))
13282 < TYPE_PRECISION (TREE_TYPE (arg1))
13283 && TYPE_PRECISION (TREE_TYPE (tem))
13284 < TYPE_PRECISION (type))
13286 unsigned HOST_WIDE_INT mask_lo;
13287 HOST_WIDE_INT mask_hi;
13288 int inner_width, outer_width;
13291 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13292 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13293 if (outer_width > TYPE_PRECISION (type))
13294 outer_width = TYPE_PRECISION (type);
13296 if (outer_width > HOST_BITS_PER_WIDE_INT)
13298 mask_hi = ((unsigned HOST_WIDE_INT) -1
13299 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13305 mask_lo = ((unsigned HOST_WIDE_INT) -1
13306 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13308 if (inner_width > HOST_BITS_PER_WIDE_INT)
13310 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13311 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13315 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13316 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13318 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13319 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13321 tem_type = signed_type_for (TREE_TYPE (tem));
13322 tem = fold_convert_loc (loc, tem_type, tem);
13324 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13325 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13327 tem_type = unsigned_type_for (TREE_TYPE (tem));
13328 tem = fold_convert_loc (loc, tem_type, tem);
13336 fold_convert_loc (loc, type,
13337 fold_build2_loc (loc, BIT_AND_EXPR,
13338 TREE_TYPE (tem), tem,
13339 fold_convert_loc (loc,
13344 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13345 already handled above. */
13346 if (TREE_CODE (arg0) == BIT_AND_EXPR
13347 && integer_onep (TREE_OPERAND (arg0, 1))
13348 && integer_zerop (op2)
13349 && integer_pow2p (arg1))
13351 tree tem = TREE_OPERAND (arg0, 0);
13353 if (TREE_CODE (tem) == RSHIFT_EXPR
13354 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13355 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13356 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13357 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13358 TREE_OPERAND (tem, 0), arg1);
13361 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13362 is probably obsolete because the first operand should be a
13363 truth value (that's why we have the two cases above), but let's
13364 leave it in until we can confirm this for all front-ends. */
13365 if (integer_zerop (op2)
13366 && TREE_CODE (arg0) == NE_EXPR
13367 && integer_zerop (TREE_OPERAND (arg0, 1))
13368 && integer_pow2p (arg1)
13369 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13370 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13371 arg1, OEP_ONLY_CONST))
13372 return pedantic_non_lvalue_loc (loc,
13373 fold_convert_loc (loc, type,
13374 TREE_OPERAND (arg0, 0)));
13376 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13377 if (integer_zerop (op2)
13378 && truth_value_p (TREE_CODE (arg0))
13379 && truth_value_p (TREE_CODE (arg1)))
13380 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13381 fold_convert_loc (loc, type, arg0),
13384 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13385 if (integer_onep (op2)
13386 && truth_value_p (TREE_CODE (arg0))
13387 && truth_value_p (TREE_CODE (arg1)))
13389 /* Only perform transformation if ARG0 is easily inverted. */
13390 tem = fold_truth_not_expr (loc, arg0);
13392 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13393 fold_convert_loc (loc, type, tem),
13397 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13398 if (integer_zerop (arg1)
13399 && truth_value_p (TREE_CODE (arg0))
13400 && truth_value_p (TREE_CODE (op2)))
13402 /* Only perform transformation if ARG0 is easily inverted. */
13403 tem = fold_truth_not_expr (loc, arg0);
13405 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13406 fold_convert_loc (loc, type, tem),
13410 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13411 if (integer_onep (arg1)
13412 && truth_value_p (TREE_CODE (arg0))
13413 && truth_value_p (TREE_CODE (op2)))
13414 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13415 fold_convert_loc (loc, type, arg0),
13421 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13422 of fold_ternary on them. */
13423 gcc_unreachable ();
13425 case BIT_FIELD_REF:
13426 if ((TREE_CODE (arg0) == VECTOR_CST
13427 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13428 && type == TREE_TYPE (TREE_TYPE (arg0)))
13430 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13431 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13434 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13435 && (idx % width) == 0
13436 && (idx = idx / width)
13437 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13439 tree elements = NULL_TREE;
13441 if (TREE_CODE (arg0) == VECTOR_CST)
13442 elements = TREE_VECTOR_CST_ELTS (arg0);
13445 unsigned HOST_WIDE_INT idx;
13448 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13449 elements = tree_cons (NULL_TREE, value, elements);
13451 while (idx-- > 0 && elements)
13452 elements = TREE_CHAIN (elements);
13454 return TREE_VALUE (elements);
13456 return fold_convert_loc (loc, type, integer_zero_node);
13460 /* A bit-field-ref that referenced the full argument can be stripped. */
13461 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13462 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13463 && integer_zerop (op2))
13464 return fold_convert_loc (loc, type, arg0);
13470 } /* switch (code) */
13473 /* Perform constant folding and related simplification of EXPR.
13474 The related simplifications include x*1 => x, x*0 => 0, etc.,
13475 and application of the associative law.
13476 NOP_EXPR conversions may be removed freely (as long as we
13477 are careful not to change the type of the overall expression).
13478 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13479 but we can constant-fold them if they have constant operands. */
13481 #ifdef ENABLE_FOLD_CHECKING
13482 # define fold(x) fold_1 (x)
13483 static tree fold_1 (tree);
13489 const tree t = expr;
13490 enum tree_code code = TREE_CODE (t);
13491 enum tree_code_class kind = TREE_CODE_CLASS (code);
13493 location_t loc = EXPR_LOCATION (expr);
13495 /* Return right away if a constant. */
13496 if (kind == tcc_constant)
13499 /* CALL_EXPR-like objects with variable numbers of operands are
13500 treated specially. */
13501 if (kind == tcc_vl_exp)
13503 if (code == CALL_EXPR)
13505 tem = fold_call_expr (loc, expr, false);
13506 return tem ? tem : expr;
13511 if (IS_EXPR_CODE_CLASS (kind))
13513 tree type = TREE_TYPE (t);
13514 tree op0, op1, op2;
13516 switch (TREE_CODE_LENGTH (code))
13519 op0 = TREE_OPERAND (t, 0);
13520 tem = fold_unary_loc (loc, code, type, op0);
13521 return tem ? tem : expr;
13523 op0 = TREE_OPERAND (t, 0);
13524 op1 = TREE_OPERAND (t, 1);
13525 tem = fold_binary_loc (loc, code, type, op0, op1);
13526 return tem ? tem : expr;
13528 op0 = TREE_OPERAND (t, 0);
13529 op1 = TREE_OPERAND (t, 1);
13530 op2 = TREE_OPERAND (t, 2);
13531 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
13532 return tem ? tem : expr;
13542 tree op0 = TREE_OPERAND (t, 0);
13543 tree op1 = TREE_OPERAND (t, 1);
13545 if (TREE_CODE (op1) == INTEGER_CST
13546 && TREE_CODE (op0) == CONSTRUCTOR
13547 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13549 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13550 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13551 unsigned HOST_WIDE_INT begin = 0;
13553 /* Find a matching index by means of a binary search. */
13554 while (begin != end)
13556 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13557 tree index = VEC_index (constructor_elt, elts, middle)->index;
13559 if (TREE_CODE (index) == INTEGER_CST
13560 && tree_int_cst_lt (index, op1))
13561 begin = middle + 1;
13562 else if (TREE_CODE (index) == INTEGER_CST
13563 && tree_int_cst_lt (op1, index))
13565 else if (TREE_CODE (index) == RANGE_EXPR
13566 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13567 begin = middle + 1;
13568 else if (TREE_CODE (index) == RANGE_EXPR
13569 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13572 return VEC_index (constructor_elt, elts, middle)->value;
13580 return fold (DECL_INITIAL (t));
13584 } /* switch (code) */
13587 #ifdef ENABLE_FOLD_CHECKING
13590 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13591 static void fold_check_failed (const_tree, const_tree);
13592 void print_fold_checksum (const_tree);
13594 /* When --enable-checking=fold, compute a digest of expr before
13595 and after actual fold call to see if fold did not accidentally
13596 change original expr. */
13602 struct md5_ctx ctx;
13603 unsigned char checksum_before[16], checksum_after[16];
13606 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13607 md5_init_ctx (&ctx);
13608 fold_checksum_tree (expr, &ctx, ht);
13609 md5_finish_ctx (&ctx, checksum_before);
13612 ret = fold_1 (expr);
13614 md5_init_ctx (&ctx);
13615 fold_checksum_tree (expr, &ctx, ht);
13616 md5_finish_ctx (&ctx, checksum_after);
13619 if (memcmp (checksum_before, checksum_after, 16))
13620 fold_check_failed (expr, ret);
13626 print_fold_checksum (const_tree expr)
13628 struct md5_ctx ctx;
13629 unsigned char checksum[16], cnt;
13632 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13633 md5_init_ctx (&ctx);
13634 fold_checksum_tree (expr, &ctx, ht);
13635 md5_finish_ctx (&ctx, checksum);
13637 for (cnt = 0; cnt < 16; ++cnt)
13638 fprintf (stderr, "%02x", checksum[cnt]);
13639 putc ('\n', stderr);
13643 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13645 internal_error ("fold check: original tree changed by fold");
13649 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13652 enum tree_code code;
13653 union tree_node buf;
13658 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13659 <= sizeof (struct tree_function_decl))
13660 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13663 slot = (void **) htab_find_slot (ht, expr, INSERT);
13666 *slot = CONST_CAST_TREE (expr);
13667 code = TREE_CODE (expr);
13668 if (TREE_CODE_CLASS (code) == tcc_declaration
13669 && DECL_ASSEMBLER_NAME_SET_P (expr))
13671 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13672 memcpy ((char *) &buf, expr, tree_size (expr));
13673 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13674 expr = (tree) &buf;
13676 else if (TREE_CODE_CLASS (code) == tcc_type
13677 && (TYPE_POINTER_TO (expr)
13678 || TYPE_REFERENCE_TO (expr)
13679 || TYPE_CACHED_VALUES_P (expr)
13680 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13681 || TYPE_NEXT_VARIANT (expr)))
13683 /* Allow these fields to be modified. */
13685 memcpy ((char *) &buf, expr, tree_size (expr));
13686 expr = tmp = (tree) &buf;
13687 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13688 TYPE_POINTER_TO (tmp) = NULL;
13689 TYPE_REFERENCE_TO (tmp) = NULL;
13690 TYPE_NEXT_VARIANT (tmp) = NULL;
13691 if (TYPE_CACHED_VALUES_P (tmp))
13693 TYPE_CACHED_VALUES_P (tmp) = 0;
13694 TYPE_CACHED_VALUES (tmp) = NULL;
13697 md5_process_bytes (expr, tree_size (expr), ctx);
13698 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13699 if (TREE_CODE_CLASS (code) != tcc_type
13700 && TREE_CODE_CLASS (code) != tcc_declaration
13701 && code != TREE_LIST
13702 && code != SSA_NAME)
13703 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13704 switch (TREE_CODE_CLASS (code))
13710 md5_process_bytes (TREE_STRING_POINTER (expr),
13711 TREE_STRING_LENGTH (expr), ctx);
13714 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13715 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13718 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13724 case tcc_exceptional:
13728 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13729 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13730 expr = TREE_CHAIN (expr);
13731 goto recursive_label;
13734 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13735 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13741 case tcc_expression:
13742 case tcc_reference:
13743 case tcc_comparison:
13746 case tcc_statement:
13748 len = TREE_OPERAND_LENGTH (expr);
13749 for (i = 0; i < len; ++i)
13750 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13752 case tcc_declaration:
13753 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13754 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13755 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13757 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13758 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13759 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13760 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13761 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13763 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13764 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13766 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13768 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13769 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13770 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13774 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13775 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13776 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13777 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13778 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13779 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13780 if (INTEGRAL_TYPE_P (expr)
13781 || SCALAR_FLOAT_TYPE_P (expr))
13783 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13784 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13786 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13787 if (TREE_CODE (expr) == RECORD_TYPE
13788 || TREE_CODE (expr) == UNION_TYPE
13789 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13790 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13791 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13798 /* Helper function for outputting the checksum of a tree T. When
13799 debugging with gdb, you can "define mynext" to be "next" followed
13800 by "call debug_fold_checksum (op0)", then just trace down till the
13803 DEBUG_FUNCTION void
13804 debug_fold_checksum (const_tree t)
13807 unsigned char checksum[16];
13808 struct md5_ctx ctx;
13809 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13811 md5_init_ctx (&ctx);
13812 fold_checksum_tree (t, &ctx, ht);
13813 md5_finish_ctx (&ctx, checksum);
13816 for (i = 0; i < 16; i++)
13817 fprintf (stderr, "%d ", checksum[i]);
13819 fprintf (stderr, "\n");
13824 /* Fold a unary tree expression with code CODE of type TYPE with an
13825 operand OP0. LOC is the location of the resulting expression.
13826 Return a folded expression if successful. Otherwise, return a tree
13827 expression with code CODE of type TYPE with an operand OP0. */
13830 fold_build1_stat_loc (location_t loc,
13831 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13834 #ifdef ENABLE_FOLD_CHECKING
13835 unsigned char checksum_before[16], checksum_after[16];
13836 struct md5_ctx ctx;
13839 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13840 md5_init_ctx (&ctx);
13841 fold_checksum_tree (op0, &ctx, ht);
13842 md5_finish_ctx (&ctx, checksum_before);
13846 tem = fold_unary_loc (loc, code, type, op0);
13849 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
13850 SET_EXPR_LOCATION (tem, loc);
13853 #ifdef ENABLE_FOLD_CHECKING
13854 md5_init_ctx (&ctx);
13855 fold_checksum_tree (op0, &ctx, ht);
13856 md5_finish_ctx (&ctx, checksum_after);
13859 if (memcmp (checksum_before, checksum_after, 16))
13860 fold_check_failed (op0, tem);
13865 /* Fold a binary tree expression with code CODE of type TYPE with
13866 operands OP0 and OP1. LOC is the location of the resulting
13867 expression. Return a folded expression if successful. Otherwise,
13868 return a tree expression with code CODE of type TYPE with operands
13872 fold_build2_stat_loc (location_t loc,
13873 enum tree_code code, tree type, tree op0, tree op1
13877 #ifdef ENABLE_FOLD_CHECKING
13878 unsigned char checksum_before_op0[16],
13879 checksum_before_op1[16],
13880 checksum_after_op0[16],
13881 checksum_after_op1[16];
13882 struct md5_ctx ctx;
13885 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13886 md5_init_ctx (&ctx);
13887 fold_checksum_tree (op0, &ctx, ht);
13888 md5_finish_ctx (&ctx, checksum_before_op0);
13891 md5_init_ctx (&ctx);
13892 fold_checksum_tree (op1, &ctx, ht);
13893 md5_finish_ctx (&ctx, checksum_before_op1);
13897 tem = fold_binary_loc (loc, code, type, op0, op1);
13900 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
13901 SET_EXPR_LOCATION (tem, loc);
13904 #ifdef ENABLE_FOLD_CHECKING
13905 md5_init_ctx (&ctx);
13906 fold_checksum_tree (op0, &ctx, ht);
13907 md5_finish_ctx (&ctx, checksum_after_op0);
13910 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13911 fold_check_failed (op0, tem);
13913 md5_init_ctx (&ctx);
13914 fold_checksum_tree (op1, &ctx, ht);
13915 md5_finish_ctx (&ctx, checksum_after_op1);
13918 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13919 fold_check_failed (op1, tem);
13924 /* Fold a ternary tree expression with code CODE of type TYPE with
13925 operands OP0, OP1, and OP2. Return a folded expression if
13926 successful. Otherwise, return a tree expression with code CODE of
13927 type TYPE with operands OP0, OP1, and OP2. */
13930 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
13931 tree op0, tree op1, tree op2 MEM_STAT_DECL)
13934 #ifdef ENABLE_FOLD_CHECKING
13935 unsigned char checksum_before_op0[16],
13936 checksum_before_op1[16],
13937 checksum_before_op2[16],
13938 checksum_after_op0[16],
13939 checksum_after_op1[16],
13940 checksum_after_op2[16];
13941 struct md5_ctx ctx;
13944 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13945 md5_init_ctx (&ctx);
13946 fold_checksum_tree (op0, &ctx, ht);
13947 md5_finish_ctx (&ctx, checksum_before_op0);
13950 md5_init_ctx (&ctx);
13951 fold_checksum_tree (op1, &ctx, ht);
13952 md5_finish_ctx (&ctx, checksum_before_op1);
13955 md5_init_ctx (&ctx);
13956 fold_checksum_tree (op2, &ctx, ht);
13957 md5_finish_ctx (&ctx, checksum_before_op2);
13961 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
13962 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
13965 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
13966 SET_EXPR_LOCATION (tem, loc);
13969 #ifdef ENABLE_FOLD_CHECKING
13970 md5_init_ctx (&ctx);
13971 fold_checksum_tree (op0, &ctx, ht);
13972 md5_finish_ctx (&ctx, checksum_after_op0);
13975 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
13976 fold_check_failed (op0, tem);
13978 md5_init_ctx (&ctx);
13979 fold_checksum_tree (op1, &ctx, ht);
13980 md5_finish_ctx (&ctx, checksum_after_op1);
13983 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
13984 fold_check_failed (op1, tem);
13986 md5_init_ctx (&ctx);
13987 fold_checksum_tree (op2, &ctx, ht);
13988 md5_finish_ctx (&ctx, checksum_after_op2);
13991 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
13992 fold_check_failed (op2, tem);
13997 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
13998 arguments in ARGARRAY, and a null static chain.
13999 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14000 of type TYPE from the given operands as constructed by build_call_array. */
14003 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14004 int nargs, tree *argarray)
14007 #ifdef ENABLE_FOLD_CHECKING
14008 unsigned char checksum_before_fn[16],
14009 checksum_before_arglist[16],
14010 checksum_after_fn[16],
14011 checksum_after_arglist[16];
14012 struct md5_ctx ctx;
14016 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14017 md5_init_ctx (&ctx);
14018 fold_checksum_tree (fn, &ctx, ht);
14019 md5_finish_ctx (&ctx, checksum_before_fn);
14022 md5_init_ctx (&ctx);
14023 for (i = 0; i < nargs; i++)
14024 fold_checksum_tree (argarray[i], &ctx, ht);
14025 md5_finish_ctx (&ctx, checksum_before_arglist);
14029 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14031 #ifdef ENABLE_FOLD_CHECKING
14032 md5_init_ctx (&ctx);
14033 fold_checksum_tree (fn, &ctx, ht);
14034 md5_finish_ctx (&ctx, checksum_after_fn);
14037 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14038 fold_check_failed (fn, tem);
14040 md5_init_ctx (&ctx);
14041 for (i = 0; i < nargs; i++)
14042 fold_checksum_tree (argarray[i], &ctx, ht);
14043 md5_finish_ctx (&ctx, checksum_after_arglist);
14046 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14047 fold_check_failed (NULL_TREE, tem);
14052 /* Perform constant folding and related simplification of initializer
14053 expression EXPR. These behave identically to "fold_buildN" but ignore
14054 potential run-time traps and exceptions that fold must preserve. */
14056 #define START_FOLD_INIT \
14057 int saved_signaling_nans = flag_signaling_nans;\
14058 int saved_trapping_math = flag_trapping_math;\
14059 int saved_rounding_math = flag_rounding_math;\
14060 int saved_trapv = flag_trapv;\
14061 int saved_folding_initializer = folding_initializer;\
14062 flag_signaling_nans = 0;\
14063 flag_trapping_math = 0;\
14064 flag_rounding_math = 0;\
14066 folding_initializer = 1;
14068 #define END_FOLD_INIT \
14069 flag_signaling_nans = saved_signaling_nans;\
14070 flag_trapping_math = saved_trapping_math;\
14071 flag_rounding_math = saved_rounding_math;\
14072 flag_trapv = saved_trapv;\
14073 folding_initializer = saved_folding_initializer;
14076 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14077 tree type, tree op)
14082 result = fold_build1_loc (loc, code, type, op);
14089 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14090 tree type, tree op0, tree op1)
14095 result = fold_build2_loc (loc, code, type, op0, op1);
14102 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14103 tree type, tree op0, tree op1, tree op2)
14108 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14115 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14116 int nargs, tree *argarray)
14121 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14127 #undef START_FOLD_INIT
14128 #undef END_FOLD_INIT
14130 /* Determine if first argument is a multiple of second argument. Return 0 if
14131 it is not, or we cannot easily determined it to be.
14133 An example of the sort of thing we care about (at this point; this routine
14134 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14135 fold cases do now) is discovering that
14137 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14143 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14145 This code also handles discovering that
14147 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14149 is a multiple of 8 so we don't have to worry about dealing with a
14150 possible remainder.
14152 Note that we *look* inside a SAVE_EXPR only to determine how it was
14153 calculated; it is not safe for fold to do much of anything else with the
14154 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14155 at run time. For example, the latter example above *cannot* be implemented
14156 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14157 evaluation time of the original SAVE_EXPR is not necessarily the same at
14158 the time the new expression is evaluated. The only optimization of this
14159 sort that would be valid is changing
14161 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14165 SAVE_EXPR (I) * SAVE_EXPR (J)
14167 (where the same SAVE_EXPR (J) is used in the original and the
14168 transformed version). */
14171 multiple_of_p (tree type, const_tree top, const_tree bottom)
14173 if (operand_equal_p (top, bottom, 0))
14176 if (TREE_CODE (type) != INTEGER_TYPE)
14179 switch (TREE_CODE (top))
14182 /* Bitwise and provides a power of two multiple. If the mask is
14183 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14184 if (!integer_pow2p (bottom))
14189 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14190 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14194 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14195 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14198 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14202 op1 = TREE_OPERAND (top, 1);
14203 /* const_binop may not detect overflow correctly,
14204 so check for it explicitly here. */
14205 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14206 > TREE_INT_CST_LOW (op1)
14207 && TREE_INT_CST_HIGH (op1) == 0
14208 && 0 != (t1 = fold_convert (type,
14209 const_binop (LSHIFT_EXPR,
14212 && !TREE_OVERFLOW (t1))
14213 return multiple_of_p (type, t1, bottom);
14218 /* Can't handle conversions from non-integral or wider integral type. */
14219 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14220 || (TYPE_PRECISION (type)
14221 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14224 /* .. fall through ... */
14227 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14230 return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
14231 && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
14234 if (TREE_CODE (bottom) != INTEGER_CST
14235 || integer_zerop (bottom)
14236 || (TYPE_UNSIGNED (type)
14237 && (tree_int_cst_sgn (top) < 0
14238 || tree_int_cst_sgn (bottom) < 0)))
14240 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14248 /* Return true if CODE or TYPE is known to be non-negative. */
14251 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14253 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14254 && truth_value_p (code))
14255 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14256 have a signed:1 type (where the value is -1 and 0). */
14261 /* Return true if (CODE OP0) is known to be non-negative. If the return
14262 value is based on the assumption that signed overflow is undefined,
14263 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14264 *STRICT_OVERFLOW_P. */
14267 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14268 bool *strict_overflow_p)
14270 if (TYPE_UNSIGNED (type))
14276 /* We can't return 1 if flag_wrapv is set because
14277 ABS_EXPR<INT_MIN> = INT_MIN. */
14278 if (!INTEGRAL_TYPE_P (type))
14280 if (TYPE_OVERFLOW_UNDEFINED (type))
14282 *strict_overflow_p = true;
14287 case NON_LVALUE_EXPR:
14289 case FIX_TRUNC_EXPR:
14290 return tree_expr_nonnegative_warnv_p (op0,
14291 strict_overflow_p);
14295 tree inner_type = TREE_TYPE (op0);
14296 tree outer_type = type;
14298 if (TREE_CODE (outer_type) == REAL_TYPE)
14300 if (TREE_CODE (inner_type) == REAL_TYPE)
14301 return tree_expr_nonnegative_warnv_p (op0,
14302 strict_overflow_p);
14303 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14305 if (TYPE_UNSIGNED (inner_type))
14307 return tree_expr_nonnegative_warnv_p (op0,
14308 strict_overflow_p);
14311 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14313 if (TREE_CODE (inner_type) == REAL_TYPE)
14314 return tree_expr_nonnegative_warnv_p (op0,
14315 strict_overflow_p);
14316 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14317 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14318 && TYPE_UNSIGNED (inner_type);
14324 return tree_simple_nonnegative_warnv_p (code, type);
14327 /* We don't know sign of `t', so be conservative and return false. */
14331 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14332 value is based on the assumption that signed overflow is undefined,
14333 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14334 *STRICT_OVERFLOW_P. */
14337 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14338 tree op1, bool *strict_overflow_p)
14340 if (TYPE_UNSIGNED (type))
14345 case POINTER_PLUS_EXPR:
14347 if (FLOAT_TYPE_P (type))
14348 return (tree_expr_nonnegative_warnv_p (op0,
14350 && tree_expr_nonnegative_warnv_p (op1,
14351 strict_overflow_p));
14353 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14354 both unsigned and at least 2 bits shorter than the result. */
14355 if (TREE_CODE (type) == INTEGER_TYPE
14356 && TREE_CODE (op0) == NOP_EXPR
14357 && TREE_CODE (op1) == NOP_EXPR)
14359 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14360 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14361 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14362 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14364 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14365 TYPE_PRECISION (inner2)) + 1;
14366 return prec < TYPE_PRECISION (type);
14372 if (FLOAT_TYPE_P (type))
14374 /* x * x for floating point x is always non-negative. */
14375 if (operand_equal_p (op0, op1, 0))
14377 return (tree_expr_nonnegative_warnv_p (op0,
14379 && tree_expr_nonnegative_warnv_p (op1,
14380 strict_overflow_p));
14383 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14384 both unsigned and their total bits is shorter than the result. */
14385 if (TREE_CODE (type) == INTEGER_TYPE
14386 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14387 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14389 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14390 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14392 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14393 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14396 bool unsigned0 = TYPE_UNSIGNED (inner0);
14397 bool unsigned1 = TYPE_UNSIGNED (inner1);
14399 if (TREE_CODE (op0) == INTEGER_CST)
14400 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14402 if (TREE_CODE (op1) == INTEGER_CST)
14403 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14405 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14406 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14408 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14409 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14410 : TYPE_PRECISION (inner0);
14412 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14413 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14414 : TYPE_PRECISION (inner1);
14416 return precision0 + precision1 < TYPE_PRECISION (type);
14423 return (tree_expr_nonnegative_warnv_p (op0,
14425 || tree_expr_nonnegative_warnv_p (op1,
14426 strict_overflow_p));
14432 case TRUNC_DIV_EXPR:
14433 case CEIL_DIV_EXPR:
14434 case FLOOR_DIV_EXPR:
14435 case ROUND_DIV_EXPR:
14436 return (tree_expr_nonnegative_warnv_p (op0,
14438 && tree_expr_nonnegative_warnv_p (op1,
14439 strict_overflow_p));
14441 case TRUNC_MOD_EXPR:
14442 case CEIL_MOD_EXPR:
14443 case FLOOR_MOD_EXPR:
14444 case ROUND_MOD_EXPR:
14445 return tree_expr_nonnegative_warnv_p (op0,
14446 strict_overflow_p);
14448 return tree_simple_nonnegative_warnv_p (code, type);
14451 /* We don't know sign of `t', so be conservative and return false. */
14455 /* Return true if T is known to be non-negative. If the return
14456 value is based on the assumption that signed overflow is undefined,
14457 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14458 *STRICT_OVERFLOW_P. */
14461 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14463 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14466 switch (TREE_CODE (t))
14469 return tree_int_cst_sgn (t) >= 0;
14472 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14475 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14478 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14480 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14481 strict_overflow_p));
14483 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14486 /* We don't know sign of `t', so be conservative and return false. */
14490 /* Return true if T is known to be non-negative. If the return
14491 value is based on the assumption that signed overflow is undefined,
14492 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14493 *STRICT_OVERFLOW_P. */
14496 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14497 tree arg0, tree arg1, bool *strict_overflow_p)
14499 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14500 switch (DECL_FUNCTION_CODE (fndecl))
14502 CASE_FLT_FN (BUILT_IN_ACOS):
14503 CASE_FLT_FN (BUILT_IN_ACOSH):
14504 CASE_FLT_FN (BUILT_IN_CABS):
14505 CASE_FLT_FN (BUILT_IN_COSH):
14506 CASE_FLT_FN (BUILT_IN_ERFC):
14507 CASE_FLT_FN (BUILT_IN_EXP):
14508 CASE_FLT_FN (BUILT_IN_EXP10):
14509 CASE_FLT_FN (BUILT_IN_EXP2):
14510 CASE_FLT_FN (BUILT_IN_FABS):
14511 CASE_FLT_FN (BUILT_IN_FDIM):
14512 CASE_FLT_FN (BUILT_IN_HYPOT):
14513 CASE_FLT_FN (BUILT_IN_POW10):
14514 CASE_INT_FN (BUILT_IN_FFS):
14515 CASE_INT_FN (BUILT_IN_PARITY):
14516 CASE_INT_FN (BUILT_IN_POPCOUNT):
14517 case BUILT_IN_BSWAP32:
14518 case BUILT_IN_BSWAP64:
14522 CASE_FLT_FN (BUILT_IN_SQRT):
14523 /* sqrt(-0.0) is -0.0. */
14524 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14526 return tree_expr_nonnegative_warnv_p (arg0,
14527 strict_overflow_p);
14529 CASE_FLT_FN (BUILT_IN_ASINH):
14530 CASE_FLT_FN (BUILT_IN_ATAN):
14531 CASE_FLT_FN (BUILT_IN_ATANH):
14532 CASE_FLT_FN (BUILT_IN_CBRT):
14533 CASE_FLT_FN (BUILT_IN_CEIL):
14534 CASE_FLT_FN (BUILT_IN_ERF):
14535 CASE_FLT_FN (BUILT_IN_EXPM1):
14536 CASE_FLT_FN (BUILT_IN_FLOOR):
14537 CASE_FLT_FN (BUILT_IN_FMOD):
14538 CASE_FLT_FN (BUILT_IN_FREXP):
14539 CASE_FLT_FN (BUILT_IN_LCEIL):
14540 CASE_FLT_FN (BUILT_IN_LDEXP):
14541 CASE_FLT_FN (BUILT_IN_LFLOOR):
14542 CASE_FLT_FN (BUILT_IN_LLCEIL):
14543 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14544 CASE_FLT_FN (BUILT_IN_LLRINT):
14545 CASE_FLT_FN (BUILT_IN_LLROUND):
14546 CASE_FLT_FN (BUILT_IN_LRINT):
14547 CASE_FLT_FN (BUILT_IN_LROUND):
14548 CASE_FLT_FN (BUILT_IN_MODF):
14549 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14550 CASE_FLT_FN (BUILT_IN_RINT):
14551 CASE_FLT_FN (BUILT_IN_ROUND):
14552 CASE_FLT_FN (BUILT_IN_SCALB):
14553 CASE_FLT_FN (BUILT_IN_SCALBLN):
14554 CASE_FLT_FN (BUILT_IN_SCALBN):
14555 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14556 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14557 CASE_FLT_FN (BUILT_IN_SINH):
14558 CASE_FLT_FN (BUILT_IN_TANH):
14559 CASE_FLT_FN (BUILT_IN_TRUNC):
14560 /* True if the 1st argument is nonnegative. */
14561 return tree_expr_nonnegative_warnv_p (arg0,
14562 strict_overflow_p);
14564 CASE_FLT_FN (BUILT_IN_FMAX):
14565 /* True if the 1st OR 2nd arguments are nonnegative. */
14566 return (tree_expr_nonnegative_warnv_p (arg0,
14568 || (tree_expr_nonnegative_warnv_p (arg1,
14569 strict_overflow_p)));
14571 CASE_FLT_FN (BUILT_IN_FMIN):
14572 /* True if the 1st AND 2nd arguments are nonnegative. */
14573 return (tree_expr_nonnegative_warnv_p (arg0,
14575 && (tree_expr_nonnegative_warnv_p (arg1,
14576 strict_overflow_p)));
14578 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14579 /* True if the 2nd argument is nonnegative. */
14580 return tree_expr_nonnegative_warnv_p (arg1,
14581 strict_overflow_p);
14583 CASE_FLT_FN (BUILT_IN_POWI):
14584 /* True if the 1st argument is nonnegative or the second
14585 argument is an even integer. */
14586 if (TREE_CODE (arg1) == INTEGER_CST
14587 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14589 return tree_expr_nonnegative_warnv_p (arg0,
14590 strict_overflow_p);
14592 CASE_FLT_FN (BUILT_IN_POW):
14593 /* True if the 1st argument is nonnegative or the second
14594 argument is an even integer valued real. */
14595 if (TREE_CODE (arg1) == REAL_CST)
14600 c = TREE_REAL_CST (arg1);
14601 n = real_to_integer (&c);
14604 REAL_VALUE_TYPE cint;
14605 real_from_integer (&cint, VOIDmode, n,
14606 n < 0 ? -1 : 0, 0);
14607 if (real_identical (&c, &cint))
14611 return tree_expr_nonnegative_warnv_p (arg0,
14612 strict_overflow_p);
14617 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14621 /* Return true if T is known to be non-negative. If the return
14622 value is based on the assumption that signed overflow is undefined,
14623 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14624 *STRICT_OVERFLOW_P. */
14627 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14629 enum tree_code code = TREE_CODE (t);
14630 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14637 tree temp = TARGET_EXPR_SLOT (t);
14638 t = TARGET_EXPR_INITIAL (t);
14640 /* If the initializer is non-void, then it's a normal expression
14641 that will be assigned to the slot. */
14642 if (!VOID_TYPE_P (t))
14643 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14645 /* Otherwise, the initializer sets the slot in some way. One common
14646 way is an assignment statement at the end of the initializer. */
14649 if (TREE_CODE (t) == BIND_EXPR)
14650 t = expr_last (BIND_EXPR_BODY (t));
14651 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14652 || TREE_CODE (t) == TRY_CATCH_EXPR)
14653 t = expr_last (TREE_OPERAND (t, 0));
14654 else if (TREE_CODE (t) == STATEMENT_LIST)
14659 if (TREE_CODE (t) == MODIFY_EXPR
14660 && TREE_OPERAND (t, 0) == temp)
14661 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14662 strict_overflow_p);
14669 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14670 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14672 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14673 get_callee_fndecl (t),
14676 strict_overflow_p);
14678 case COMPOUND_EXPR:
14680 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14681 strict_overflow_p);
14683 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14684 strict_overflow_p);
14686 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14687 strict_overflow_p);
14690 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14694 /* We don't know sign of `t', so be conservative and return false. */
14698 /* Return true if T is known to be non-negative. If the return
14699 value is based on the assumption that signed overflow is undefined,
14700 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14701 *STRICT_OVERFLOW_P. */
14704 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14706 enum tree_code code;
14707 if (t == error_mark_node)
14710 code = TREE_CODE (t);
14711 switch (TREE_CODE_CLASS (code))
14714 case tcc_comparison:
14715 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14717 TREE_OPERAND (t, 0),
14718 TREE_OPERAND (t, 1),
14719 strict_overflow_p);
14722 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14724 TREE_OPERAND (t, 0),
14725 strict_overflow_p);
14728 case tcc_declaration:
14729 case tcc_reference:
14730 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14738 case TRUTH_AND_EXPR:
14739 case TRUTH_OR_EXPR:
14740 case TRUTH_XOR_EXPR:
14741 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14743 TREE_OPERAND (t, 0),
14744 TREE_OPERAND (t, 1),
14745 strict_overflow_p);
14746 case TRUTH_NOT_EXPR:
14747 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14749 TREE_OPERAND (t, 0),
14750 strict_overflow_p);
14757 case WITH_SIZE_EXPR:
14759 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14762 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14766 /* Return true if `t' is known to be non-negative. Handle warnings
14767 about undefined signed overflow. */
14770 tree_expr_nonnegative_p (tree t)
14772 bool ret, strict_overflow_p;
14774 strict_overflow_p = false;
14775 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14776 if (strict_overflow_p)
14777 fold_overflow_warning (("assuming signed overflow does not occur when "
14778 "determining that expression is always "
14780 WARN_STRICT_OVERFLOW_MISC);
14785 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14786 For floating point we further ensure that T is not denormal.
14787 Similar logic is present in nonzero_address in rtlanal.h.
14789 If the return value is based on the assumption that signed overflow
14790 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14791 change *STRICT_OVERFLOW_P. */
14794 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14795 bool *strict_overflow_p)
14800 return tree_expr_nonzero_warnv_p (op0,
14801 strict_overflow_p);
14805 tree inner_type = TREE_TYPE (op0);
14806 tree outer_type = type;
14808 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14809 && tree_expr_nonzero_warnv_p (op0,
14810 strict_overflow_p));
14814 case NON_LVALUE_EXPR:
14815 return tree_expr_nonzero_warnv_p (op0,
14816 strict_overflow_p);
14825 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14826 For floating point we further ensure that T is not denormal.
14827 Similar logic is present in nonzero_address in rtlanal.h.
14829 If the return value is based on the assumption that signed overflow
14830 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14831 change *STRICT_OVERFLOW_P. */
14834 tree_binary_nonzero_warnv_p (enum tree_code code,
14837 tree op1, bool *strict_overflow_p)
14839 bool sub_strict_overflow_p;
14842 case POINTER_PLUS_EXPR:
14844 if (TYPE_OVERFLOW_UNDEFINED (type))
14846 /* With the presence of negative values it is hard
14847 to say something. */
14848 sub_strict_overflow_p = false;
14849 if (!tree_expr_nonnegative_warnv_p (op0,
14850 &sub_strict_overflow_p)
14851 || !tree_expr_nonnegative_warnv_p (op1,
14852 &sub_strict_overflow_p))
14854 /* One of operands must be positive and the other non-negative. */
14855 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14856 overflows, on a twos-complement machine the sum of two
14857 nonnegative numbers can never be zero. */
14858 return (tree_expr_nonzero_warnv_p (op0,
14860 || tree_expr_nonzero_warnv_p (op1,
14861 strict_overflow_p));
14866 if (TYPE_OVERFLOW_UNDEFINED (type))
14868 if (tree_expr_nonzero_warnv_p (op0,
14870 && tree_expr_nonzero_warnv_p (op1,
14871 strict_overflow_p))
14873 *strict_overflow_p = true;
14880 sub_strict_overflow_p = false;
14881 if (tree_expr_nonzero_warnv_p (op0,
14882 &sub_strict_overflow_p)
14883 && tree_expr_nonzero_warnv_p (op1,
14884 &sub_strict_overflow_p))
14886 if (sub_strict_overflow_p)
14887 *strict_overflow_p = true;
14892 sub_strict_overflow_p = false;
14893 if (tree_expr_nonzero_warnv_p (op0,
14894 &sub_strict_overflow_p))
14896 if (sub_strict_overflow_p)
14897 *strict_overflow_p = true;
14899 /* When both operands are nonzero, then MAX must be too. */
14900 if (tree_expr_nonzero_warnv_p (op1,
14901 strict_overflow_p))
14904 /* MAX where operand 0 is positive is positive. */
14905 return tree_expr_nonnegative_warnv_p (op0,
14906 strict_overflow_p);
14908 /* MAX where operand 1 is positive is positive. */
14909 else if (tree_expr_nonzero_warnv_p (op1,
14910 &sub_strict_overflow_p)
14911 && tree_expr_nonnegative_warnv_p (op1,
14912 &sub_strict_overflow_p))
14914 if (sub_strict_overflow_p)
14915 *strict_overflow_p = true;
14921 return (tree_expr_nonzero_warnv_p (op1,
14923 || tree_expr_nonzero_warnv_p (op0,
14924 strict_overflow_p));
14933 /* Return true when T is an address and is known to be nonzero.
14934 For floating point we further ensure that T is not denormal.
14935 Similar logic is present in nonzero_address in rtlanal.h.
14937 If the return value is based on the assumption that signed overflow
14938 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14939 change *STRICT_OVERFLOW_P. */
14942 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
14944 bool sub_strict_overflow_p;
14945 switch (TREE_CODE (t))
14948 return !integer_zerop (t);
14952 tree base = TREE_OPERAND (t, 0);
14953 if (!DECL_P (base))
14954 base = get_base_address (base);
14959 /* Weak declarations may link to NULL. Other things may also be NULL
14960 so protect with -fdelete-null-pointer-checks; but not variables
14961 allocated on the stack. */
14963 && (flag_delete_null_pointer_checks
14964 || (DECL_CONTEXT (base)
14965 && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
14966 && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
14967 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
14969 /* Constants are never weak. */
14970 if (CONSTANT_CLASS_P (base))
14977 sub_strict_overflow_p = false;
14978 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
14979 &sub_strict_overflow_p)
14980 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
14981 &sub_strict_overflow_p))
14983 if (sub_strict_overflow_p)
14984 *strict_overflow_p = true;
14995 /* Return true when T is an address and is known to be nonzero.
14996 For floating point we further ensure that T is not denormal.
14997 Similar logic is present in nonzero_address in rtlanal.h.
14999 If the return value is based on the assumption that signed overflow
15000 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15001 change *STRICT_OVERFLOW_P. */
15004 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15006 tree type = TREE_TYPE (t);
15007 enum tree_code code;
15009 /* Doing something useful for floating point would need more work. */
15010 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15013 code = TREE_CODE (t);
15014 switch (TREE_CODE_CLASS (code))
15017 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15018 strict_overflow_p);
15020 case tcc_comparison:
15021 return tree_binary_nonzero_warnv_p (code, type,
15022 TREE_OPERAND (t, 0),
15023 TREE_OPERAND (t, 1),
15024 strict_overflow_p);
15026 case tcc_declaration:
15027 case tcc_reference:
15028 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15036 case TRUTH_NOT_EXPR:
15037 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15038 strict_overflow_p);
15040 case TRUTH_AND_EXPR:
15041 case TRUTH_OR_EXPR:
15042 case TRUTH_XOR_EXPR:
15043 return tree_binary_nonzero_warnv_p (code, type,
15044 TREE_OPERAND (t, 0),
15045 TREE_OPERAND (t, 1),
15046 strict_overflow_p);
15053 case WITH_SIZE_EXPR:
15055 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15057 case COMPOUND_EXPR:
15060 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15061 strict_overflow_p);
15064 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15065 strict_overflow_p);
15068 return alloca_call_p (t);
15076 /* Return true when T is an address and is known to be nonzero.
15077 Handle warnings about undefined signed overflow. */
15080 tree_expr_nonzero_p (tree t)
15082 bool ret, strict_overflow_p;
15084 strict_overflow_p = false;
15085 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15086 if (strict_overflow_p)
15087 fold_overflow_warning (("assuming signed overflow does not occur when "
15088 "determining that expression is always "
15090 WARN_STRICT_OVERFLOW_MISC);
15094 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15095 attempt to fold the expression to a constant without modifying TYPE,
15098 If the expression could be simplified to a constant, then return
15099 the constant. If the expression would not be simplified to a
15100 constant, then return NULL_TREE. */
15103 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15105 tree tem = fold_binary (code, type, op0, op1);
15106 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15109 /* Given the components of a unary expression CODE, TYPE and OP0,
15110 attempt to fold the expression to a constant without modifying
15113 If the expression could be simplified to a constant, then return
15114 the constant. If the expression would not be simplified to a
15115 constant, then return NULL_TREE. */
15118 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15120 tree tem = fold_unary (code, type, op0);
15121 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15124 /* If EXP represents referencing an element in a constant string
15125 (either via pointer arithmetic or array indexing), return the
15126 tree representing the value accessed, otherwise return NULL. */
15129 fold_read_from_constant_string (tree exp)
15131 if ((TREE_CODE (exp) == INDIRECT_REF
15132 || TREE_CODE (exp) == ARRAY_REF)
15133 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15135 tree exp1 = TREE_OPERAND (exp, 0);
15138 location_t loc = EXPR_LOCATION (exp);
15140 if (TREE_CODE (exp) == INDIRECT_REF)
15141 string = string_constant (exp1, &index);
15144 tree low_bound = array_ref_low_bound (exp);
15145 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15147 /* Optimize the special-case of a zero lower bound.
15149 We convert the low_bound to sizetype to avoid some problems
15150 with constant folding. (E.g. suppose the lower bound is 1,
15151 and its mode is QI. Without the conversion,l (ARRAY
15152 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15153 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15154 if (! integer_zerop (low_bound))
15155 index = size_diffop_loc (loc, index,
15156 fold_convert_loc (loc, sizetype, low_bound));
15162 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15163 && TREE_CODE (string) == STRING_CST
15164 && TREE_CODE (index) == INTEGER_CST
15165 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15166 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15168 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15169 return build_int_cst_type (TREE_TYPE (exp),
15170 (TREE_STRING_POINTER (string)
15171 [TREE_INT_CST_LOW (index)]));
15176 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15177 an integer constant, real, or fixed-point constant.
15179 TYPE is the type of the result. */
15182 fold_negate_const (tree arg0, tree type)
15184 tree t = NULL_TREE;
15186 switch (TREE_CODE (arg0))
15190 double_int val = tree_to_double_int (arg0);
15191 int overflow = neg_double (val.low, val.high, &val.low, &val.high);
15193 t = force_fit_type_double (type, val, 1,
15194 (overflow | TREE_OVERFLOW (arg0))
15195 && !TYPE_UNSIGNED (type));
15200 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15205 FIXED_VALUE_TYPE f;
15206 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15207 &(TREE_FIXED_CST (arg0)), NULL,
15208 TYPE_SATURATING (type));
15209 t = build_fixed (type, f);
15210 /* Propagate overflow flags. */
15211 if (overflow_p | TREE_OVERFLOW (arg0))
15212 TREE_OVERFLOW (t) = 1;
15217 gcc_unreachable ();
15223 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15224 an integer constant or real constant.
15226 TYPE is the type of the result. */
15229 fold_abs_const (tree arg0, tree type)
15231 tree t = NULL_TREE;
15233 switch (TREE_CODE (arg0))
15237 double_int val = tree_to_double_int (arg0);
15239 /* If the value is unsigned or non-negative, then the absolute value
15240 is the same as the ordinary value. */
15241 if (TYPE_UNSIGNED (type)
15242 || !double_int_negative_p (val))
15245 /* If the value is negative, then the absolute value is
15251 overflow = neg_double (val.low, val.high, &val.low, &val.high);
15252 t = force_fit_type_double (type, val, -1,
15253 overflow | TREE_OVERFLOW (arg0));
15259 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15260 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15266 gcc_unreachable ();
15272 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15273 constant. TYPE is the type of the result. */
15276 fold_not_const (const_tree arg0, tree type)
15280 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15282 val = double_int_not (tree_to_double_int (arg0));
15283 return force_fit_type_double (type, val, 0, TREE_OVERFLOW (arg0));
15286 /* Given CODE, a relational operator, the target type, TYPE and two
15287 constant operands OP0 and OP1, return the result of the
15288 relational operation. If the result is not a compile time
15289 constant, then return NULL_TREE. */
15292 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15294 int result, invert;
15296 /* From here on, the only cases we handle are when the result is
15297 known to be a constant. */
15299 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15301 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15302 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15304 /* Handle the cases where either operand is a NaN. */
15305 if (real_isnan (c0) || real_isnan (c1))
15315 case UNORDERED_EXPR:
15329 if (flag_trapping_math)
15335 gcc_unreachable ();
15338 return constant_boolean_node (result, type);
15341 return constant_boolean_node (real_compare (code, c0, c1), type);
15344 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15346 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15347 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15348 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15351 /* Handle equality/inequality of complex constants. */
15352 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15354 tree rcond = fold_relational_const (code, type,
15355 TREE_REALPART (op0),
15356 TREE_REALPART (op1));
15357 tree icond = fold_relational_const (code, type,
15358 TREE_IMAGPART (op0),
15359 TREE_IMAGPART (op1));
15360 if (code == EQ_EXPR)
15361 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15362 else if (code == NE_EXPR)
15363 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15368 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15370 To compute GT, swap the arguments and do LT.
15371 To compute GE, do LT and invert the result.
15372 To compute LE, swap the arguments, do LT and invert the result.
15373 To compute NE, do EQ and invert the result.
15375 Therefore, the code below must handle only EQ and LT. */
15377 if (code == LE_EXPR || code == GT_EXPR)
15382 code = swap_tree_comparison (code);
15385 /* Note that it is safe to invert for real values here because we
15386 have already handled the one case that it matters. */
15389 if (code == NE_EXPR || code == GE_EXPR)
15392 code = invert_tree_comparison (code, false);
15395 /* Compute a result for LT or EQ if args permit;
15396 Otherwise return T. */
15397 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15399 if (code == EQ_EXPR)
15400 result = tree_int_cst_equal (op0, op1);
15401 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15402 result = INT_CST_LT_UNSIGNED (op0, op1);
15404 result = INT_CST_LT (op0, op1);
15411 return constant_boolean_node (result, type);
15414 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15415 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15419 fold_build_cleanup_point_expr (tree type, tree expr)
15421 /* If the expression does not have side effects then we don't have to wrap
15422 it with a cleanup point expression. */
15423 if (!TREE_SIDE_EFFECTS (expr))
15426 /* If the expression is a return, check to see if the expression inside the
15427 return has no side effects or the right hand side of the modify expression
15428 inside the return. If either don't have side effects set we don't need to
15429 wrap the expression in a cleanup point expression. Note we don't check the
15430 left hand side of the modify because it should always be a return decl. */
15431 if (TREE_CODE (expr) == RETURN_EXPR)
15433 tree op = TREE_OPERAND (expr, 0);
15434 if (!op || !TREE_SIDE_EFFECTS (op))
15436 op = TREE_OPERAND (op, 1);
15437 if (!TREE_SIDE_EFFECTS (op))
15441 return build1 (CLEANUP_POINT_EXPR, type, expr);
15444 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15445 of an indirection through OP0, or NULL_TREE if no simplification is
15449 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
15455 subtype = TREE_TYPE (sub);
15456 if (!POINTER_TYPE_P (subtype))
15459 if (TREE_CODE (sub) == ADDR_EXPR)
15461 tree op = TREE_OPERAND (sub, 0);
15462 tree optype = TREE_TYPE (op);
15463 /* *&CONST_DECL -> to the value of the const decl. */
15464 if (TREE_CODE (op) == CONST_DECL)
15465 return DECL_INITIAL (op);
15466 /* *&p => p; make sure to handle *&"str"[cst] here. */
15467 if (type == optype)
15469 tree fop = fold_read_from_constant_string (op);
15475 /* *(foo *)&fooarray => fooarray[0] */
15476 else if (TREE_CODE (optype) == ARRAY_TYPE
15477 && type == TREE_TYPE (optype))
15479 tree type_domain = TYPE_DOMAIN (optype);
15480 tree min_val = size_zero_node;
15481 if (type_domain && TYPE_MIN_VALUE (type_domain))
15482 min_val = TYPE_MIN_VALUE (type_domain);
15483 op0 = build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
15484 SET_EXPR_LOCATION (op0, loc);
15487 /* *(foo *)&complexfoo => __real__ complexfoo */
15488 else if (TREE_CODE (optype) == COMPLEX_TYPE
15489 && type == TREE_TYPE (optype))
15490 return fold_build1_loc (loc, REALPART_EXPR, type, op);
15491 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15492 else if (TREE_CODE (optype) == VECTOR_TYPE
15493 && type == TREE_TYPE (optype))
15495 tree part_width = TYPE_SIZE (type);
15496 tree index = bitsize_int (0);
15497 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
15501 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15502 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15503 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15505 tree op00 = TREE_OPERAND (sub, 0);
15506 tree op01 = TREE_OPERAND (sub, 1);
15510 op00type = TREE_TYPE (op00);
15511 if (TREE_CODE (op00) == ADDR_EXPR
15512 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
15513 && type == TREE_TYPE (TREE_TYPE (op00type)))
15515 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15516 tree part_width = TYPE_SIZE (type);
15517 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15518 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15519 tree index = bitsize_int (indexi);
15521 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
15522 return fold_build3_loc (loc,
15523 BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
15524 part_width, index);
15530 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15531 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15532 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15534 tree op00 = TREE_OPERAND (sub, 0);
15535 tree op01 = TREE_OPERAND (sub, 1);
15539 op00type = TREE_TYPE (op00);
15540 if (TREE_CODE (op00) == ADDR_EXPR
15541 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
15542 && type == TREE_TYPE (TREE_TYPE (op00type)))
15544 tree size = TYPE_SIZE_UNIT (type);
15545 if (tree_int_cst_equal (size, op01))
15546 return fold_build1_loc (loc, IMAGPART_EXPR, type,
15547 TREE_OPERAND (op00, 0));
15551 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15552 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15553 && type == TREE_TYPE (TREE_TYPE (subtype)))
15556 tree min_val = size_zero_node;
15557 sub = build_fold_indirect_ref_loc (loc, sub);
15558 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15559 if (type_domain && TYPE_MIN_VALUE (type_domain))
15560 min_val = TYPE_MIN_VALUE (type_domain);
15561 op0 = build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
15562 SET_EXPR_LOCATION (op0, loc);
15569 /* Builds an expression for an indirection through T, simplifying some
15573 build_fold_indirect_ref_loc (location_t loc, tree t)
15575 tree type = TREE_TYPE (TREE_TYPE (t));
15576 tree sub = fold_indirect_ref_1 (loc, type, t);
15581 t = build1 (INDIRECT_REF, type, t);
15582 SET_EXPR_LOCATION (t, loc);
15586 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15589 fold_indirect_ref_loc (location_t loc, tree t)
15591 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
15599 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15600 whose result is ignored. The type of the returned tree need not be
15601 the same as the original expression. */
15604 fold_ignored_result (tree t)
15606 if (!TREE_SIDE_EFFECTS (t))
15607 return integer_zero_node;
15610 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15613 t = TREE_OPERAND (t, 0);
15617 case tcc_comparison:
15618 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15619 t = TREE_OPERAND (t, 0);
15620 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15621 t = TREE_OPERAND (t, 1);
15626 case tcc_expression:
15627 switch (TREE_CODE (t))
15629 case COMPOUND_EXPR:
15630 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15632 t = TREE_OPERAND (t, 0);
15636 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15637 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15639 t = TREE_OPERAND (t, 0);
15652 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15653 This can only be applied to objects of a sizetype. */
15656 round_up_loc (location_t loc, tree value, int divisor)
15658 tree div = NULL_TREE;
15660 gcc_assert (divisor > 0);
15664 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15665 have to do anything. Only do this when we are not given a const,
15666 because in that case, this check is more expensive than just
15668 if (TREE_CODE (value) != INTEGER_CST)
15670 div = build_int_cst (TREE_TYPE (value), divisor);
15672 if (multiple_of_p (TREE_TYPE (value), value, div))
15676 /* If divisor is a power of two, simplify this to bit manipulation. */
15677 if (divisor == (divisor & -divisor))
15679 if (TREE_CODE (value) == INTEGER_CST)
15681 double_int val = tree_to_double_int (value);
15684 if ((val.low & (divisor - 1)) == 0)
15687 overflow_p = TREE_OVERFLOW (value);
15688 val.low &= ~(divisor - 1);
15689 val.low += divisor;
15697 return force_fit_type_double (TREE_TYPE (value), val,
15704 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15705 value = size_binop_loc (loc, PLUS_EXPR, value, t);
15706 t = build_int_cst (TREE_TYPE (value), -divisor);
15707 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15713 div = build_int_cst (TREE_TYPE (value), divisor);
15714 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
15715 value = size_binop_loc (loc, MULT_EXPR, value, div);
15721 /* Likewise, but round down. */
15724 round_down_loc (location_t loc, tree value, int divisor)
15726 tree div = NULL_TREE;
15728 gcc_assert (divisor > 0);
15732 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15733 have to do anything. Only do this when we are not given a const,
15734 because in that case, this check is more expensive than just
15736 if (TREE_CODE (value) != INTEGER_CST)
15738 div = build_int_cst (TREE_TYPE (value), divisor);
15740 if (multiple_of_p (TREE_TYPE (value), value, div))
15744 /* If divisor is a power of two, simplify this to bit manipulation. */
15745 if (divisor == (divisor & -divisor))
15749 t = build_int_cst (TREE_TYPE (value), -divisor);
15750 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15755 div = build_int_cst (TREE_TYPE (value), divisor);
15756 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
15757 value = size_binop_loc (loc, MULT_EXPR, value, div);
15763 /* Returns the pointer to the base of the object addressed by EXP and
15764 extracts the information about the offset of the access, storing it
15765 to PBITPOS and POFFSET. */
15768 split_address_to_core_and_offset (tree exp,
15769 HOST_WIDE_INT *pbitpos, tree *poffset)
15772 enum machine_mode mode;
15773 int unsignedp, volatilep;
15774 HOST_WIDE_INT bitsize;
15775 location_t loc = EXPR_LOCATION (exp);
15777 if (TREE_CODE (exp) == ADDR_EXPR)
15779 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15780 poffset, &mode, &unsignedp, &volatilep,
15782 core = build_fold_addr_expr_loc (loc, core);
15788 *poffset = NULL_TREE;
15794 /* Returns true if addresses of E1 and E2 differ by a constant, false
15795 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15798 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15801 HOST_WIDE_INT bitpos1, bitpos2;
15802 tree toffset1, toffset2, tdiff, type;
15804 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15805 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15807 if (bitpos1 % BITS_PER_UNIT != 0
15808 || bitpos2 % BITS_PER_UNIT != 0
15809 || !operand_equal_p (core1, core2, 0))
15812 if (toffset1 && toffset2)
15814 type = TREE_TYPE (toffset1);
15815 if (type != TREE_TYPE (toffset2))
15816 toffset2 = fold_convert (type, toffset2);
15818 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15819 if (!cst_and_fits_in_hwi (tdiff))
15822 *diff = int_cst_value (tdiff);
15824 else if (toffset1 || toffset2)
15826 /* If only one of the offsets is non-constant, the difference cannot
15833 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15837 /* Simplify the floating point expression EXP when the sign of the
15838 result is not significant. Return NULL_TREE if no simplification
15842 fold_strip_sign_ops (tree exp)
15845 location_t loc = EXPR_LOCATION (exp);
15847 switch (TREE_CODE (exp))
15851 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15852 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
15856 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
15858 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15859 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15860 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
15861 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
15862 arg0 ? arg0 : TREE_OPERAND (exp, 0),
15863 arg1 ? arg1 : TREE_OPERAND (exp, 1));
15866 case COMPOUND_EXPR:
15867 arg0 = TREE_OPERAND (exp, 0);
15868 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15870 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
15874 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15875 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
15877 return fold_build3_loc (loc,
15878 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
15879 arg0 ? arg0 : TREE_OPERAND (exp, 1),
15880 arg1 ? arg1 : TREE_OPERAND (exp, 2));
15885 const enum built_in_function fcode = builtin_mathfn_code (exp);
15888 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15889 /* Strip copysign function call, return the 1st argument. */
15890 arg0 = CALL_EXPR_ARG (exp, 0);
15891 arg1 = CALL_EXPR_ARG (exp, 1);
15892 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
15895 /* Strip sign ops from the argument of "odd" math functions. */
15896 if (negate_mathfn_p (fcode))
15898 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
15900 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);