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 /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
11075 ((A & N) + B) & M -> (A + B) & M
11076 Similarly if (N & M) == 0,
11077 ((A | N) + B) & M -> (A + B) & M
11078 and for - instead of + (or unary - instead of +)
11079 and/or ^ instead of |.
11080 If B is constant and (B & M) == 0, fold into A & M. */
11081 if (host_integerp (arg1, 1))
11083 unsigned HOST_WIDE_INT cst1 = tree_low_cst (arg1, 1);
11084 if (~cst1 && (cst1 & (cst1 + 1)) == 0
11085 && INTEGRAL_TYPE_P (TREE_TYPE (arg0))
11086 && (TREE_CODE (arg0) == PLUS_EXPR
11087 || TREE_CODE (arg0) == MINUS_EXPR
11088 || TREE_CODE (arg0) == NEGATE_EXPR)
11089 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
11090 || TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE))
11094 unsigned HOST_WIDE_INT cst0;
11096 /* Now we know that arg0 is (C + D) or (C - D) or
11097 -C and arg1 (M) is == (1LL << cst) - 1.
11098 Store C into PMOP[0] and D into PMOP[1]. */
11099 pmop[0] = TREE_OPERAND (arg0, 0);
11101 if (TREE_CODE (arg0) != NEGATE_EXPR)
11103 pmop[1] = TREE_OPERAND (arg0, 1);
11107 if (!host_integerp (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11108 || (tree_low_cst (TYPE_MAX_VALUE (TREE_TYPE (arg0)), 1)
11112 for (; which >= 0; which--)
11113 switch (TREE_CODE (pmop[which]))
11118 if (TREE_CODE (TREE_OPERAND (pmop[which], 1))
11121 /* tree_low_cst not used, because we don't care about
11123 cst0 = TREE_INT_CST_LOW (TREE_OPERAND (pmop[which], 1));
11125 if (TREE_CODE (pmop[which]) == BIT_AND_EXPR)
11130 else if (cst0 != 0)
11132 /* If C or D is of the form (A & N) where
11133 (N & M) == M, or of the form (A | N) or
11134 (A ^ N) where (N & M) == 0, replace it with A. */
11135 pmop[which] = TREE_OPERAND (pmop[which], 0);
11138 /* If C or D is a N where (N & M) == 0, it can be
11139 omitted (assumed 0). */
11140 if ((TREE_CODE (arg0) == PLUS_EXPR
11141 || (TREE_CODE (arg0) == MINUS_EXPR && which == 0))
11142 && (TREE_INT_CST_LOW (pmop[which]) & cst1) == 0)
11143 pmop[which] = NULL;
11149 /* Only build anything new if we optimized one or both arguments
11151 if (pmop[0] != TREE_OPERAND (arg0, 0)
11152 || (TREE_CODE (arg0) != NEGATE_EXPR
11153 && pmop[1] != TREE_OPERAND (arg0, 1)))
11155 tree utype = TREE_TYPE (arg0);
11156 if (! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
11158 /* Perform the operations in a type that has defined
11159 overflow behavior. */
11160 utype = unsigned_type_for (TREE_TYPE (arg0));
11161 if (pmop[0] != NULL)
11162 pmop[0] = fold_convert_loc (loc, utype, pmop[0]);
11163 if (pmop[1] != NULL)
11164 pmop[1] = fold_convert_loc (loc, utype, pmop[1]);
11167 if (TREE_CODE (arg0) == NEGATE_EXPR)
11168 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[0]);
11169 else if (TREE_CODE (arg0) == PLUS_EXPR)
11171 if (pmop[0] != NULL && pmop[1] != NULL)
11172 tem = fold_build2_loc (loc, PLUS_EXPR, utype,
11174 else if (pmop[0] != NULL)
11176 else if (pmop[1] != NULL)
11179 return build_int_cst (type, 0);
11181 else if (pmop[0] == NULL)
11182 tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[1]);
11184 tem = fold_build2_loc (loc, MINUS_EXPR, utype,
11186 /* TEM is now the new binary +, - or unary - replacement. */
11187 tem = fold_build2_loc (loc, BIT_AND_EXPR, utype, tem,
11188 fold_convert_loc (loc, utype, arg1));
11189 return fold_convert_loc (loc, type, tem);
11194 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11195 if (t1 != NULL_TREE)
11197 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11198 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11199 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11202 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11204 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11205 && (~TREE_INT_CST_LOW (arg1)
11206 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11208 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11211 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11213 This results in more efficient code for machines without a NOR
11214 instruction. Combine will canonicalize to the first form
11215 which will allow use of NOR instructions provided by the
11216 backend if they exist. */
11217 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11218 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11220 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11221 build2 (BIT_IOR_EXPR, type,
11222 fold_convert_loc (loc, type,
11223 TREE_OPERAND (arg0, 0)),
11224 fold_convert_loc (loc, type,
11225 TREE_OPERAND (arg1, 0))));
11228 /* If arg0 is derived from the address of an object or function, we may
11229 be able to fold this expression using the object or function's
11231 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11233 unsigned HOST_WIDE_INT modulus, residue;
11234 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11236 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11237 integer_onep (arg1));
11239 /* This works because modulus is a power of 2. If this weren't the
11240 case, we'd have to replace it by its greatest power-of-2
11241 divisor: modulus & -modulus. */
11243 return build_int_cst (type, residue & low);
11246 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11247 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11248 if the new mask might be further optimized. */
11249 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11250 || TREE_CODE (arg0) == RSHIFT_EXPR)
11251 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11252 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11253 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11254 < TYPE_PRECISION (TREE_TYPE (arg0))
11255 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11256 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11258 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11259 unsigned HOST_WIDE_INT mask
11260 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11261 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11262 tree shift_type = TREE_TYPE (arg0);
11264 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11265 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11266 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11267 && TYPE_PRECISION (TREE_TYPE (arg0))
11268 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11270 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11271 tree arg00 = TREE_OPERAND (arg0, 0);
11272 /* See if more bits can be proven as zero because of
11274 if (TREE_CODE (arg00) == NOP_EXPR
11275 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11277 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11278 if (TYPE_PRECISION (inner_type)
11279 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11280 && TYPE_PRECISION (inner_type) < prec)
11282 prec = TYPE_PRECISION (inner_type);
11283 /* See if we can shorten the right shift. */
11285 shift_type = inner_type;
11288 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11289 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11290 zerobits <<= prec - shiftc;
11291 /* For arithmetic shift if sign bit could be set, zerobits
11292 can contain actually sign bits, so no transformation is
11293 possible, unless MASK masks them all away. In that
11294 case the shift needs to be converted into logical shift. */
11295 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11296 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11298 if ((mask & zerobits) == 0)
11299 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11305 /* ((X << 16) & 0xff00) is (X, 0). */
11306 if ((mask & zerobits) == mask)
11307 return omit_one_operand_loc (loc, type,
11308 build_int_cst (type, 0), arg0);
11310 newmask = mask | zerobits;
11311 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11315 /* Only do the transformation if NEWMASK is some integer
11317 for (prec = BITS_PER_UNIT;
11318 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11319 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11321 if (prec < HOST_BITS_PER_WIDE_INT
11322 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11326 if (shift_type != TREE_TYPE (arg0))
11328 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11329 fold_convert_loc (loc, shift_type,
11330 TREE_OPERAND (arg0, 0)),
11331 TREE_OPERAND (arg0, 1));
11332 tem = fold_convert_loc (loc, type, tem);
11336 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11337 if (!tree_int_cst_equal (newmaskt, arg1))
11338 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11346 /* Don't touch a floating-point divide by zero unless the mode
11347 of the constant can represent infinity. */
11348 if (TREE_CODE (arg1) == REAL_CST
11349 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11350 && real_zerop (arg1))
11353 /* Optimize A / A to 1.0 if we don't care about
11354 NaNs or Infinities. Skip the transformation
11355 for non-real operands. */
11356 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11357 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11358 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11359 && operand_equal_p (arg0, arg1, 0))
11361 tree r = build_real (TREE_TYPE (arg0), dconst1);
11363 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11366 /* The complex version of the above A / A optimization. */
11367 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11368 && operand_equal_p (arg0, arg1, 0))
11370 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11371 if (! HONOR_NANS (TYPE_MODE (elem_type))
11372 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11374 tree r = build_real (elem_type, dconst1);
11375 /* omit_two_operands will call fold_convert for us. */
11376 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11380 /* (-A) / (-B) -> A / B */
11381 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11382 return fold_build2_loc (loc, RDIV_EXPR, type,
11383 TREE_OPERAND (arg0, 0),
11384 negate_expr (arg1));
11385 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11386 return fold_build2_loc (loc, RDIV_EXPR, type,
11387 negate_expr (arg0),
11388 TREE_OPERAND (arg1, 0));
11390 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11391 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11392 && real_onep (arg1))
11393 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11395 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11396 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11397 && real_minus_onep (arg1))
11398 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11399 negate_expr (arg0)));
11401 /* If ARG1 is a constant, we can convert this to a multiply by the
11402 reciprocal. This does not have the same rounding properties,
11403 so only do this if -freciprocal-math. We can actually
11404 always safely do it if ARG1 is a power of two, but it's hard to
11405 tell if it is or not in a portable manner. */
11406 if (TREE_CODE (arg1) == REAL_CST)
11408 if (flag_reciprocal_math
11409 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11411 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11412 /* Find the reciprocal if optimizing and the result is exact. */
11416 r = TREE_REAL_CST (arg1);
11417 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11419 tem = build_real (type, r);
11420 return fold_build2_loc (loc, MULT_EXPR, type,
11421 fold_convert_loc (loc, type, arg0), tem);
11425 /* Convert A/B/C to A/(B*C). */
11426 if (flag_reciprocal_math
11427 && TREE_CODE (arg0) == RDIV_EXPR)
11428 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11429 fold_build2_loc (loc, MULT_EXPR, type,
11430 TREE_OPERAND (arg0, 1), arg1));
11432 /* Convert A/(B/C) to (A/B)*C. */
11433 if (flag_reciprocal_math
11434 && TREE_CODE (arg1) == RDIV_EXPR)
11435 return fold_build2_loc (loc, MULT_EXPR, type,
11436 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11437 TREE_OPERAND (arg1, 0)),
11438 TREE_OPERAND (arg1, 1));
11440 /* Convert C1/(X*C2) into (C1/C2)/X. */
11441 if (flag_reciprocal_math
11442 && TREE_CODE (arg1) == MULT_EXPR
11443 && TREE_CODE (arg0) == REAL_CST
11444 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11446 tree tem = const_binop (RDIV_EXPR, arg0,
11447 TREE_OPERAND (arg1, 1));
11449 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11450 TREE_OPERAND (arg1, 0));
11453 if (flag_unsafe_math_optimizations)
11455 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11456 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11458 /* Optimize sin(x)/cos(x) as tan(x). */
11459 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11460 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11461 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11462 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11463 CALL_EXPR_ARG (arg1, 0), 0))
11465 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11467 if (tanfn != NULL_TREE)
11468 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11471 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11472 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11473 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11474 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11475 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11476 CALL_EXPR_ARG (arg1, 0), 0))
11478 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11480 if (tanfn != NULL_TREE)
11482 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11483 CALL_EXPR_ARG (arg0, 0));
11484 return fold_build2_loc (loc, RDIV_EXPR, type,
11485 build_real (type, dconst1), tmp);
11489 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11490 NaNs or Infinities. */
11491 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11492 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11493 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11495 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11496 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11498 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11499 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11500 && operand_equal_p (arg00, arg01, 0))
11502 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11504 if (cosfn != NULL_TREE)
11505 return build_call_expr_loc (loc, cosfn, 1, arg00);
11509 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11510 NaNs or Infinities. */
11511 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11512 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11513 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11515 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11516 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11518 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11519 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11520 && operand_equal_p (arg00, arg01, 0))
11522 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11524 if (cosfn != NULL_TREE)
11526 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11527 return fold_build2_loc (loc, RDIV_EXPR, type,
11528 build_real (type, dconst1),
11534 /* Optimize pow(x,c)/x as pow(x,c-1). */
11535 if (fcode0 == BUILT_IN_POW
11536 || fcode0 == BUILT_IN_POWF
11537 || fcode0 == BUILT_IN_POWL)
11539 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11540 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11541 if (TREE_CODE (arg01) == REAL_CST
11542 && !TREE_OVERFLOW (arg01)
11543 && operand_equal_p (arg1, arg00, 0))
11545 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11549 c = TREE_REAL_CST (arg01);
11550 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
11551 arg = build_real (type, c);
11552 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11556 /* Optimize a/root(b/c) into a*root(c/b). */
11557 if (BUILTIN_ROOT_P (fcode1))
11559 tree rootarg = CALL_EXPR_ARG (arg1, 0);
11561 if (TREE_CODE (rootarg) == RDIV_EXPR)
11563 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11564 tree b = TREE_OPERAND (rootarg, 0);
11565 tree c = TREE_OPERAND (rootarg, 1);
11567 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
11569 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
11570 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
11574 /* Optimize x/expN(y) into x*expN(-y). */
11575 if (BUILTIN_EXPONENT_P (fcode1))
11577 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11578 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
11579 arg1 = build_call_expr_loc (loc,
11581 fold_convert_loc (loc, type, arg));
11582 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11585 /* Optimize x/pow(y,z) into x*pow(y,-z). */
11586 if (fcode1 == BUILT_IN_POW
11587 || fcode1 == BUILT_IN_POWF
11588 || fcode1 == BUILT_IN_POWL)
11590 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11591 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11592 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11593 tree neg11 = fold_convert_loc (loc, type,
11594 negate_expr (arg11));
11595 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
11596 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
11601 case TRUNC_DIV_EXPR:
11602 case FLOOR_DIV_EXPR:
11603 /* Simplify A / (B << N) where A and B are positive and B is
11604 a power of 2, to A >> (N + log2(B)). */
11605 strict_overflow_p = false;
11606 if (TREE_CODE (arg1) == LSHIFT_EXPR
11607 && (TYPE_UNSIGNED (type)
11608 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11610 tree sval = TREE_OPERAND (arg1, 0);
11611 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
11613 tree sh_cnt = TREE_OPERAND (arg1, 1);
11614 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
11616 if (strict_overflow_p)
11617 fold_overflow_warning (("assuming signed overflow does not "
11618 "occur when simplifying A / (B << N)"),
11619 WARN_STRICT_OVERFLOW_MISC);
11621 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
11622 sh_cnt, build_int_cst (NULL_TREE, pow2));
11623 return fold_build2_loc (loc, RSHIFT_EXPR, type,
11624 fold_convert_loc (loc, type, arg0), sh_cnt);
11628 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
11629 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
11630 if (INTEGRAL_TYPE_P (type)
11631 && TYPE_UNSIGNED (type)
11632 && code == FLOOR_DIV_EXPR)
11633 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
11637 case ROUND_DIV_EXPR:
11638 case CEIL_DIV_EXPR:
11639 case EXACT_DIV_EXPR:
11640 if (integer_onep (arg1))
11641 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11642 if (integer_zerop (arg1))
11644 /* X / -1 is -X. */
11645 if (!TYPE_UNSIGNED (type)
11646 && TREE_CODE (arg1) == INTEGER_CST
11647 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11648 && TREE_INT_CST_HIGH (arg1) == -1)
11649 return fold_convert_loc (loc, type, negate_expr (arg0));
11651 /* Convert -A / -B to A / B when the type is signed and overflow is
11653 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11654 && TREE_CODE (arg0) == NEGATE_EXPR
11655 && negate_expr_p (arg1))
11657 if (INTEGRAL_TYPE_P (type))
11658 fold_overflow_warning (("assuming signed overflow does not occur "
11659 "when distributing negation across "
11661 WARN_STRICT_OVERFLOW_MISC);
11662 return fold_build2_loc (loc, code, type,
11663 fold_convert_loc (loc, type,
11664 TREE_OPERAND (arg0, 0)),
11665 fold_convert_loc (loc, type,
11666 negate_expr (arg1)));
11668 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
11669 && TREE_CODE (arg1) == NEGATE_EXPR
11670 && negate_expr_p (arg0))
11672 if (INTEGRAL_TYPE_P (type))
11673 fold_overflow_warning (("assuming signed overflow does not occur "
11674 "when distributing negation across "
11676 WARN_STRICT_OVERFLOW_MISC);
11677 return fold_build2_loc (loc, code, type,
11678 fold_convert_loc (loc, type,
11679 negate_expr (arg0)),
11680 fold_convert_loc (loc, type,
11681 TREE_OPERAND (arg1, 0)));
11684 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
11685 operation, EXACT_DIV_EXPR.
11687 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
11688 At one time others generated faster code, it's not clear if they do
11689 after the last round to changes to the DIV code in expmed.c. */
11690 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
11691 && multiple_of_p (type, arg0, arg1))
11692 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
11694 strict_overflow_p = false;
11695 if (TREE_CODE (arg1) == INTEGER_CST
11696 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11697 &strict_overflow_p)))
11699 if (strict_overflow_p)
11700 fold_overflow_warning (("assuming signed overflow does not occur "
11701 "when simplifying division"),
11702 WARN_STRICT_OVERFLOW_MISC);
11703 return fold_convert_loc (loc, type, tem);
11708 case CEIL_MOD_EXPR:
11709 case FLOOR_MOD_EXPR:
11710 case ROUND_MOD_EXPR:
11711 case TRUNC_MOD_EXPR:
11712 /* X % 1 is always zero, but be sure to preserve any side
11714 if (integer_onep (arg1))
11715 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11717 /* X % 0, return X % 0 unchanged so that we can get the
11718 proper warnings and errors. */
11719 if (integer_zerop (arg1))
11722 /* 0 % X is always zero, but be sure to preserve any side
11723 effects in X. Place this after checking for X == 0. */
11724 if (integer_zerop (arg0))
11725 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11727 /* X % -1 is zero. */
11728 if (!TYPE_UNSIGNED (type)
11729 && TREE_CODE (arg1) == INTEGER_CST
11730 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
11731 && TREE_INT_CST_HIGH (arg1) == -1)
11732 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11734 /* X % -C is the same as X % C. */
11735 if (code == TRUNC_MOD_EXPR
11736 && !TYPE_UNSIGNED (type)
11737 && TREE_CODE (arg1) == INTEGER_CST
11738 && !TREE_OVERFLOW (arg1)
11739 && TREE_INT_CST_HIGH (arg1) < 0
11740 && !TYPE_OVERFLOW_TRAPS (type)
11741 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
11742 && !sign_bit_p (arg1, arg1))
11743 return fold_build2_loc (loc, code, type,
11744 fold_convert_loc (loc, type, arg0),
11745 fold_convert_loc (loc, type,
11746 negate_expr (arg1)));
11748 /* X % -Y is the same as X % Y. */
11749 if (code == TRUNC_MOD_EXPR
11750 && !TYPE_UNSIGNED (type)
11751 && TREE_CODE (arg1) == NEGATE_EXPR
11752 && !TYPE_OVERFLOW_TRAPS (type))
11753 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
11754 fold_convert_loc (loc, type,
11755 TREE_OPERAND (arg1, 0)));
11757 strict_overflow_p = false;
11758 if (TREE_CODE (arg1) == INTEGER_CST
11759 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11760 &strict_overflow_p)))
11762 if (strict_overflow_p)
11763 fold_overflow_warning (("assuming signed overflow does not occur "
11764 "when simplifying modulus"),
11765 WARN_STRICT_OVERFLOW_MISC);
11766 return fold_convert_loc (loc, type, tem);
11769 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
11770 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
11771 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
11772 && (TYPE_UNSIGNED (type)
11773 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
11776 /* Also optimize A % (C << N) where C is a power of 2,
11777 to A & ((C << N) - 1). */
11778 if (TREE_CODE (arg1) == LSHIFT_EXPR)
11779 c = TREE_OPERAND (arg1, 0);
11781 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
11784 = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
11785 build_int_cst (TREE_TYPE (arg1), 1));
11786 if (strict_overflow_p)
11787 fold_overflow_warning (("assuming signed overflow does not "
11788 "occur when simplifying "
11789 "X % (power of two)"),
11790 WARN_STRICT_OVERFLOW_MISC);
11791 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11792 fold_convert_loc (loc, type, arg0),
11793 fold_convert_loc (loc, type, mask));
11801 if (integer_all_onesp (arg0))
11802 return omit_one_operand_loc (loc, type, arg0, arg1);
11806 /* Optimize -1 >> x for arithmetic right shifts. */
11807 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
11808 && tree_expr_nonnegative_p (arg1))
11809 return omit_one_operand_loc (loc, type, arg0, arg1);
11810 /* ... fall through ... */
11814 if (integer_zerop (arg1))
11815 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11816 if (integer_zerop (arg0))
11817 return omit_one_operand_loc (loc, type, arg0, arg1);
11819 /* Since negative shift count is not well-defined,
11820 don't try to compute it in the compiler. */
11821 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
11824 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
11825 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
11826 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11827 && host_integerp (TREE_OPERAND (arg0, 1), false)
11828 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11830 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
11831 + TREE_INT_CST_LOW (arg1));
11833 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
11834 being well defined. */
11835 if (low >= TYPE_PRECISION (type))
11837 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
11838 low = low % TYPE_PRECISION (type);
11839 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
11840 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
11841 TREE_OPERAND (arg0, 0));
11843 low = TYPE_PRECISION (type) - 1;
11846 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
11847 build_int_cst (type, low));
11850 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
11851 into x & ((unsigned)-1 >> c) for unsigned types. */
11852 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
11853 || (TYPE_UNSIGNED (type)
11854 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
11855 && host_integerp (arg1, false)
11856 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
11857 && host_integerp (TREE_OPERAND (arg0, 1), false)
11858 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
11860 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11861 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
11867 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11869 lshift = build_int_cst (type, -1);
11870 lshift = int_const_binop (code, lshift, arg1, 0);
11872 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
11876 /* Rewrite an LROTATE_EXPR by a constant into an
11877 RROTATE_EXPR by a new constant. */
11878 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
11880 tree tem = build_int_cst (TREE_TYPE (arg1),
11881 TYPE_PRECISION (type));
11882 tem = const_binop (MINUS_EXPR, tem, arg1);
11883 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
11886 /* If we have a rotate of a bit operation with the rotate count and
11887 the second operand of the bit operation both constant,
11888 permute the two operations. */
11889 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11890 && (TREE_CODE (arg0) == BIT_AND_EXPR
11891 || TREE_CODE (arg0) == BIT_IOR_EXPR
11892 || TREE_CODE (arg0) == BIT_XOR_EXPR)
11893 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11894 return fold_build2_loc (loc, TREE_CODE (arg0), type,
11895 fold_build2_loc (loc, code, type,
11896 TREE_OPERAND (arg0, 0), arg1),
11897 fold_build2_loc (loc, code, type,
11898 TREE_OPERAND (arg0, 1), arg1));
11900 /* Two consecutive rotates adding up to the precision of the
11901 type can be ignored. */
11902 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
11903 && TREE_CODE (arg0) == RROTATE_EXPR
11904 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11905 && TREE_INT_CST_HIGH (arg1) == 0
11906 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
11907 && ((TREE_INT_CST_LOW (arg1)
11908 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
11909 == (unsigned int) TYPE_PRECISION (type)))
11910 return TREE_OPERAND (arg0, 0);
11912 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
11913 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
11914 if the latter can be further optimized. */
11915 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
11916 && TREE_CODE (arg0) == BIT_AND_EXPR
11917 && TREE_CODE (arg1) == INTEGER_CST
11918 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11920 tree mask = fold_build2_loc (loc, code, type,
11921 fold_convert_loc (loc, type,
11922 TREE_OPERAND (arg0, 1)),
11924 tree shift = fold_build2_loc (loc, code, type,
11925 fold_convert_loc (loc, type,
11926 TREE_OPERAND (arg0, 0)),
11928 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
11936 if (operand_equal_p (arg0, arg1, 0))
11937 return omit_one_operand_loc (loc, type, arg0, arg1);
11938 if (INTEGRAL_TYPE_P (type)
11939 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
11940 return omit_one_operand_loc (loc, type, arg1, arg0);
11941 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
11947 if (operand_equal_p (arg0, arg1, 0))
11948 return omit_one_operand_loc (loc, type, arg0, arg1);
11949 if (INTEGRAL_TYPE_P (type)
11950 && TYPE_MAX_VALUE (type)
11951 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
11952 return omit_one_operand_loc (loc, type, arg1, arg0);
11953 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
11958 case TRUTH_ANDIF_EXPR:
11959 /* Note that the operands of this must be ints
11960 and their values must be 0 or 1.
11961 ("true" is a fixed value perhaps depending on the language.) */
11962 /* If first arg is constant zero, return it. */
11963 if (integer_zerop (arg0))
11964 return fold_convert_loc (loc, type, arg0);
11965 case TRUTH_AND_EXPR:
11966 /* If either arg is constant true, drop it. */
11967 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
11968 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
11969 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
11970 /* Preserve sequence points. */
11971 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
11972 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11973 /* If second arg is constant zero, result is zero, but first arg
11974 must be evaluated. */
11975 if (integer_zerop (arg1))
11976 return omit_one_operand_loc (loc, type, arg1, arg0);
11977 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
11978 case will be handled here. */
11979 if (integer_zerop (arg0))
11980 return omit_one_operand_loc (loc, type, arg0, arg1);
11982 /* !X && X is always false. */
11983 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
11984 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11985 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11986 /* X && !X is always false. */
11987 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
11988 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11989 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11991 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
11992 means A >= Y && A != MAX, but in this case we know that
11995 if (!TREE_SIDE_EFFECTS (arg0)
11996 && !TREE_SIDE_EFFECTS (arg1))
11998 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
11999 if (tem && !operand_equal_p (tem, arg0, 0))
12000 return fold_build2_loc (loc, code, type, tem, arg1);
12002 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12003 if (tem && !operand_equal_p (tem, arg1, 0))
12004 return fold_build2_loc (loc, code, type, arg0, tem);
12008 /* We only do these simplifications if we are optimizing. */
12012 /* Check for things like (A || B) && (A || C). We can convert this
12013 to A || (B && C). Note that either operator can be any of the four
12014 truth and/or operations and the transformation will still be
12015 valid. Also note that we only care about order for the
12016 ANDIF and ORIF operators. If B contains side effects, this
12017 might change the truth-value of A. */
12018 if (TREE_CODE (arg0) == TREE_CODE (arg1)
12019 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
12020 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
12021 || TREE_CODE (arg0) == TRUTH_AND_EXPR
12022 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
12023 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
12025 tree a00 = TREE_OPERAND (arg0, 0);
12026 tree a01 = TREE_OPERAND (arg0, 1);
12027 tree a10 = TREE_OPERAND (arg1, 0);
12028 tree a11 = TREE_OPERAND (arg1, 1);
12029 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
12030 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
12031 && (code == TRUTH_AND_EXPR
12032 || code == TRUTH_OR_EXPR));
12034 if (operand_equal_p (a00, a10, 0))
12035 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12036 fold_build2_loc (loc, code, type, a01, a11));
12037 else if (commutative && operand_equal_p (a00, a11, 0))
12038 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12039 fold_build2_loc (loc, code, type, a01, a10));
12040 else if (commutative && operand_equal_p (a01, a10, 0))
12041 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
12042 fold_build2_loc (loc, code, type, a00, a11));
12044 /* This case if tricky because we must either have commutative
12045 operators or else A10 must not have side-effects. */
12047 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
12048 && operand_equal_p (a01, a11, 0))
12049 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12050 fold_build2_loc (loc, code, type, a00, a10),
12054 /* See if we can build a range comparison. */
12055 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
12058 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg0) == TRUTH_ORIF_EXPR)
12059 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg0) == TRUTH_ANDIF_EXPR))
12061 tem = merge_truthop_with_opposite_arm (loc, arg0, arg1, true);
12063 return fold_build2_loc (loc, code, type, tem, arg1);
12066 if ((code == TRUTH_ANDIF_EXPR && TREE_CODE (arg1) == TRUTH_ORIF_EXPR)
12067 || (code == TRUTH_ORIF_EXPR && TREE_CODE (arg1) == TRUTH_ANDIF_EXPR))
12069 tem = merge_truthop_with_opposite_arm (loc, arg1, arg0, false);
12071 return fold_build2_loc (loc, code, type, arg0, tem);
12074 /* Check for the possibility of merging component references. If our
12075 lhs is another similar operation, try to merge its rhs with our
12076 rhs. Then try to merge our lhs and rhs. */
12077 if (TREE_CODE (arg0) == code
12078 && 0 != (tem = fold_truthop (loc, code, type,
12079 TREE_OPERAND (arg0, 1), arg1)))
12080 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12082 if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
12087 case TRUTH_ORIF_EXPR:
12088 /* Note that the operands of this must be ints
12089 and their values must be 0 or true.
12090 ("true" is a fixed value perhaps depending on the language.) */
12091 /* If first arg is constant true, return it. */
12092 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12093 return fold_convert_loc (loc, type, arg0);
12094 case TRUTH_OR_EXPR:
12095 /* If either arg is constant zero, drop it. */
12096 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12097 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12098 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12099 /* Preserve sequence points. */
12100 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12101 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12102 /* If second arg is constant true, result is true, but we must
12103 evaluate first arg. */
12104 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12105 return omit_one_operand_loc (loc, type, arg1, arg0);
12106 /* Likewise for first arg, but note this only occurs here for
12108 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12109 return omit_one_operand_loc (loc, type, arg0, arg1);
12111 /* !X || X is always true. */
12112 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12113 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12114 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12115 /* X || !X is always true. */
12116 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12117 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12118 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12122 case TRUTH_XOR_EXPR:
12123 /* If the second arg is constant zero, drop it. */
12124 if (integer_zerop (arg1))
12125 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12126 /* If the second arg is constant true, this is a logical inversion. */
12127 if (integer_onep (arg1))
12129 /* Only call invert_truthvalue if operand is a truth value. */
12130 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12131 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12133 tem = invert_truthvalue_loc (loc, arg0);
12134 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12136 /* Identical arguments cancel to zero. */
12137 if (operand_equal_p (arg0, arg1, 0))
12138 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12140 /* !X ^ X is always true. */
12141 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12142 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12143 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12145 /* X ^ !X is always true. */
12146 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12147 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12148 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12154 tem = fold_comparison (loc, code, type, op0, op1);
12155 if (tem != NULL_TREE)
12158 /* bool_var != 0 becomes bool_var. */
12159 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12160 && code == NE_EXPR)
12161 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12163 /* bool_var == 1 becomes bool_var. */
12164 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12165 && code == EQ_EXPR)
12166 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12168 /* bool_var != 1 becomes !bool_var. */
12169 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12170 && code == NE_EXPR)
12171 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12172 fold_convert_loc (loc, type, arg0));
12174 /* bool_var == 0 becomes !bool_var. */
12175 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12176 && code == EQ_EXPR)
12177 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12178 fold_convert_loc (loc, type, arg0));
12180 /* !exp != 0 becomes !exp */
12181 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12182 && code == NE_EXPR)
12183 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12185 /* If this is an equality comparison of the address of two non-weak,
12186 unaliased symbols neither of which are extern (since we do not
12187 have access to attributes for externs), then we know the result. */
12188 if (TREE_CODE (arg0) == ADDR_EXPR
12189 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12190 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12191 && ! lookup_attribute ("alias",
12192 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12193 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12194 && TREE_CODE (arg1) == ADDR_EXPR
12195 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12196 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12197 && ! lookup_attribute ("alias",
12198 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12199 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12201 /* We know that we're looking at the address of two
12202 non-weak, unaliased, static _DECL nodes.
12204 It is both wasteful and incorrect to call operand_equal_p
12205 to compare the two ADDR_EXPR nodes. It is wasteful in that
12206 all we need to do is test pointer equality for the arguments
12207 to the two ADDR_EXPR nodes. It is incorrect to use
12208 operand_equal_p as that function is NOT equivalent to a
12209 C equality test. It can in fact return false for two
12210 objects which would test as equal using the C equality
12212 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12213 return constant_boolean_node (equal
12214 ? code == EQ_EXPR : code != EQ_EXPR,
12218 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12219 a MINUS_EXPR of a constant, we can convert it into a comparison with
12220 a revised constant as long as no overflow occurs. */
12221 if (TREE_CODE (arg1) == INTEGER_CST
12222 && (TREE_CODE (arg0) == PLUS_EXPR
12223 || TREE_CODE (arg0) == MINUS_EXPR)
12224 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12225 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12226 ? MINUS_EXPR : PLUS_EXPR,
12227 fold_convert_loc (loc, TREE_TYPE (arg0),
12229 TREE_OPERAND (arg0, 1)))
12230 && !TREE_OVERFLOW (tem))
12231 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12233 /* Similarly for a NEGATE_EXPR. */
12234 if (TREE_CODE (arg0) == NEGATE_EXPR
12235 && TREE_CODE (arg1) == INTEGER_CST
12236 && 0 != (tem = negate_expr (arg1))
12237 && TREE_CODE (tem) == INTEGER_CST
12238 && !TREE_OVERFLOW (tem))
12239 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12241 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12242 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12243 && TREE_CODE (arg1) == INTEGER_CST
12244 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12245 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12246 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12247 fold_convert_loc (loc,
12250 TREE_OPERAND (arg0, 1)));
12252 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12253 if ((TREE_CODE (arg0) == PLUS_EXPR
12254 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12255 || TREE_CODE (arg0) == MINUS_EXPR)
12256 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12257 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12258 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12260 tree val = TREE_OPERAND (arg0, 1);
12261 return omit_two_operands_loc (loc, type,
12262 fold_build2_loc (loc, code, type,
12264 build_int_cst (TREE_TYPE (val),
12266 TREE_OPERAND (arg0, 0), arg1);
12269 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12270 if (TREE_CODE (arg0) == MINUS_EXPR
12271 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12272 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
12273 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12275 return omit_two_operands_loc (loc, type,
12277 ? boolean_true_node : boolean_false_node,
12278 TREE_OPERAND (arg0, 1), arg1);
12281 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12282 for !=. Don't do this for ordered comparisons due to overflow. */
12283 if (TREE_CODE (arg0) == MINUS_EXPR
12284 && integer_zerop (arg1))
12285 return fold_build2_loc (loc, code, type,
12286 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12288 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12289 if (TREE_CODE (arg0) == ABS_EXPR
12290 && (integer_zerop (arg1) || real_zerop (arg1)))
12291 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12293 /* If this is an EQ or NE comparison with zero and ARG0 is
12294 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12295 two operations, but the latter can be done in one less insn
12296 on machines that have only two-operand insns or on which a
12297 constant cannot be the first operand. */
12298 if (TREE_CODE (arg0) == BIT_AND_EXPR
12299 && integer_zerop (arg1))
12301 tree arg00 = TREE_OPERAND (arg0, 0);
12302 tree arg01 = TREE_OPERAND (arg0, 1);
12303 if (TREE_CODE (arg00) == LSHIFT_EXPR
12304 && integer_onep (TREE_OPERAND (arg00, 0)))
12306 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12307 arg01, TREE_OPERAND (arg00, 1));
12308 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12309 build_int_cst (TREE_TYPE (arg0), 1));
12310 return fold_build2_loc (loc, code, type,
12311 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12314 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12315 && integer_onep (TREE_OPERAND (arg01, 0)))
12317 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12318 arg00, TREE_OPERAND (arg01, 1));
12319 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12320 build_int_cst (TREE_TYPE (arg0), 1));
12321 return fold_build2_loc (loc, code, type,
12322 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12327 /* If this is an NE or EQ comparison of zero against the result of a
12328 signed MOD operation whose second operand is a power of 2, make
12329 the MOD operation unsigned since it is simpler and equivalent. */
12330 if (integer_zerop (arg1)
12331 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12332 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12333 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12334 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12335 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12336 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12338 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12339 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12340 fold_convert_loc (loc, newtype,
12341 TREE_OPERAND (arg0, 0)),
12342 fold_convert_loc (loc, newtype,
12343 TREE_OPERAND (arg0, 1)));
12345 return fold_build2_loc (loc, code, type, newmod,
12346 fold_convert_loc (loc, newtype, arg1));
12349 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12350 C1 is a valid shift constant, and C2 is a power of two, i.e.
12352 if (TREE_CODE (arg0) == BIT_AND_EXPR
12353 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12354 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12356 && integer_pow2p (TREE_OPERAND (arg0, 1))
12357 && integer_zerop (arg1))
12359 tree itype = TREE_TYPE (arg0);
12360 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12361 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12363 /* Check for a valid shift count. */
12364 if (TREE_INT_CST_HIGH (arg001) == 0
12365 && TREE_INT_CST_LOW (arg001) < prec)
12367 tree arg01 = TREE_OPERAND (arg0, 1);
12368 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12369 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12370 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12371 can be rewritten as (X & (C2 << C1)) != 0. */
12372 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12374 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12375 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12376 return fold_build2_loc (loc, code, type, tem, arg1);
12378 /* Otherwise, for signed (arithmetic) shifts,
12379 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12380 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12381 else if (!TYPE_UNSIGNED (itype))
12382 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12383 arg000, build_int_cst (itype, 0));
12384 /* Otherwise, of unsigned (logical) shifts,
12385 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12386 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12388 return omit_one_operand_loc (loc, type,
12389 code == EQ_EXPR ? integer_one_node
12390 : integer_zero_node,
12395 /* If this is an NE comparison of zero with an AND of one, remove the
12396 comparison since the AND will give the correct value. */
12397 if (code == NE_EXPR
12398 && integer_zerop (arg1)
12399 && TREE_CODE (arg0) == BIT_AND_EXPR
12400 && integer_onep (TREE_OPERAND (arg0, 1)))
12401 return fold_convert_loc (loc, type, arg0);
12403 /* If we have (A & C) == C where C is a power of 2, convert this into
12404 (A & C) != 0. Similarly for NE_EXPR. */
12405 if (TREE_CODE (arg0) == BIT_AND_EXPR
12406 && integer_pow2p (TREE_OPERAND (arg0, 1))
12407 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12408 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12409 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12410 integer_zero_node));
12412 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12413 bit, then fold the expression into A < 0 or A >= 0. */
12414 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12418 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12419 Similarly for NE_EXPR. */
12420 if (TREE_CODE (arg0) == BIT_AND_EXPR
12421 && TREE_CODE (arg1) == INTEGER_CST
12422 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12424 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12425 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12426 TREE_OPERAND (arg0, 1));
12427 tree dandnotc = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12429 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12430 if (integer_nonzerop (dandnotc))
12431 return omit_one_operand_loc (loc, type, rslt, arg0);
12434 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12435 Similarly for NE_EXPR. */
12436 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12437 && TREE_CODE (arg1) == INTEGER_CST
12438 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12440 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12441 tree candnotd = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12442 TREE_OPERAND (arg0, 1), notd);
12443 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12444 if (integer_nonzerop (candnotd))
12445 return omit_one_operand_loc (loc, type, rslt, arg0);
12448 /* If this is a comparison of a field, we may be able to simplify it. */
12449 if ((TREE_CODE (arg0) == COMPONENT_REF
12450 || TREE_CODE (arg0) == BIT_FIELD_REF)
12451 /* Handle the constant case even without -O
12452 to make sure the warnings are given. */
12453 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12455 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12460 /* Optimize comparisons of strlen vs zero to a compare of the
12461 first character of the string vs zero. To wit,
12462 strlen(ptr) == 0 => *ptr == 0
12463 strlen(ptr) != 0 => *ptr != 0
12464 Other cases should reduce to one of these two (or a constant)
12465 due to the return value of strlen being unsigned. */
12466 if (TREE_CODE (arg0) == CALL_EXPR
12467 && integer_zerop (arg1))
12469 tree fndecl = get_callee_fndecl (arg0);
12472 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12473 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12474 && call_expr_nargs (arg0) == 1
12475 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12477 tree iref = build_fold_indirect_ref_loc (loc,
12478 CALL_EXPR_ARG (arg0, 0));
12479 return fold_build2_loc (loc, code, type, iref,
12480 build_int_cst (TREE_TYPE (iref), 0));
12484 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12485 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12486 if (TREE_CODE (arg0) == RSHIFT_EXPR
12487 && integer_zerop (arg1)
12488 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12490 tree arg00 = TREE_OPERAND (arg0, 0);
12491 tree arg01 = TREE_OPERAND (arg0, 1);
12492 tree itype = TREE_TYPE (arg00);
12493 if (TREE_INT_CST_HIGH (arg01) == 0
12494 && TREE_INT_CST_LOW (arg01)
12495 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12497 if (TYPE_UNSIGNED (itype))
12499 itype = signed_type_for (itype);
12500 arg00 = fold_convert_loc (loc, itype, arg00);
12502 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12503 type, arg00, build_int_cst (itype, 0));
12507 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12508 if (integer_zerop (arg1)
12509 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12510 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12511 TREE_OPERAND (arg0, 1));
12513 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12514 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12515 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12516 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12517 build_int_cst (TREE_TYPE (arg1), 0));
12518 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12519 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12520 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12521 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12522 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12523 build_int_cst (TREE_TYPE (arg1), 0));
12525 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12526 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12527 && TREE_CODE (arg1) == INTEGER_CST
12528 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12529 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12530 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12531 TREE_OPERAND (arg0, 1), arg1));
12533 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12534 (X & C) == 0 when C is a single bit. */
12535 if (TREE_CODE (arg0) == BIT_AND_EXPR
12536 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12537 && integer_zerop (arg1)
12538 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12540 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12541 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12542 TREE_OPERAND (arg0, 1));
12543 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12547 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12548 constant C is a power of two, i.e. a single bit. */
12549 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12550 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
12551 && integer_zerop (arg1)
12552 && integer_pow2p (TREE_OPERAND (arg0, 1))
12553 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12554 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12556 tree arg00 = TREE_OPERAND (arg0, 0);
12557 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12558 arg00, build_int_cst (TREE_TYPE (arg00), 0));
12561 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
12562 when is C is a power of two, i.e. a single bit. */
12563 if (TREE_CODE (arg0) == BIT_AND_EXPR
12564 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
12565 && integer_zerop (arg1)
12566 && integer_pow2p (TREE_OPERAND (arg0, 1))
12567 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
12568 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
12570 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12571 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
12572 arg000, TREE_OPERAND (arg0, 1));
12573 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12574 tem, build_int_cst (TREE_TYPE (tem), 0));
12577 if (integer_zerop (arg1)
12578 && tree_expr_nonzero_p (arg0))
12580 tree res = constant_boolean_node (code==NE_EXPR, type);
12581 return omit_one_operand_loc (loc, type, res, arg0);
12584 /* Fold -X op -Y as X op Y, where op is eq/ne. */
12585 if (TREE_CODE (arg0) == NEGATE_EXPR
12586 && TREE_CODE (arg1) == NEGATE_EXPR)
12587 return fold_build2_loc (loc, code, type,
12588 TREE_OPERAND (arg0, 0),
12589 TREE_OPERAND (arg1, 0));
12591 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
12592 if (TREE_CODE (arg0) == BIT_AND_EXPR
12593 && TREE_CODE (arg1) == BIT_AND_EXPR)
12595 tree arg00 = TREE_OPERAND (arg0, 0);
12596 tree arg01 = TREE_OPERAND (arg0, 1);
12597 tree arg10 = TREE_OPERAND (arg1, 0);
12598 tree arg11 = TREE_OPERAND (arg1, 1);
12599 tree itype = TREE_TYPE (arg0);
12601 if (operand_equal_p (arg01, arg11, 0))
12602 return fold_build2_loc (loc, code, type,
12603 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12604 fold_build2_loc (loc,
12605 BIT_XOR_EXPR, itype,
12608 build_int_cst (itype, 0));
12610 if (operand_equal_p (arg01, arg10, 0))
12611 return fold_build2_loc (loc, code, type,
12612 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12613 fold_build2_loc (loc,
12614 BIT_XOR_EXPR, itype,
12617 build_int_cst (itype, 0));
12619 if (operand_equal_p (arg00, arg11, 0))
12620 return fold_build2_loc (loc, code, type,
12621 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12622 fold_build2_loc (loc,
12623 BIT_XOR_EXPR, itype,
12626 build_int_cst (itype, 0));
12628 if (operand_equal_p (arg00, arg10, 0))
12629 return fold_build2_loc (loc, code, type,
12630 fold_build2_loc (loc, BIT_AND_EXPR, itype,
12631 fold_build2_loc (loc,
12632 BIT_XOR_EXPR, itype,
12635 build_int_cst (itype, 0));
12638 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12639 && TREE_CODE (arg1) == BIT_XOR_EXPR)
12641 tree arg00 = TREE_OPERAND (arg0, 0);
12642 tree arg01 = TREE_OPERAND (arg0, 1);
12643 tree arg10 = TREE_OPERAND (arg1, 0);
12644 tree arg11 = TREE_OPERAND (arg1, 1);
12645 tree itype = TREE_TYPE (arg0);
12647 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
12648 operand_equal_p guarantees no side-effects so we don't need
12649 to use omit_one_operand on Z. */
12650 if (operand_equal_p (arg01, arg11, 0))
12651 return fold_build2_loc (loc, code, type, arg00, arg10);
12652 if (operand_equal_p (arg01, arg10, 0))
12653 return fold_build2_loc (loc, code, type, arg00, arg11);
12654 if (operand_equal_p (arg00, arg11, 0))
12655 return fold_build2_loc (loc, code, type, arg01, arg10);
12656 if (operand_equal_p (arg00, arg10, 0))
12657 return fold_build2_loc (loc, code, type, arg01, arg11);
12659 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
12660 if (TREE_CODE (arg01) == INTEGER_CST
12661 && TREE_CODE (arg11) == INTEGER_CST)
12662 return fold_build2_loc (loc, code, type,
12663 fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00,
12664 fold_build2_loc (loc,
12665 BIT_XOR_EXPR, itype,
12670 /* Attempt to simplify equality/inequality comparisons of complex
12671 values. Only lower the comparison if the result is known or
12672 can be simplified to a single scalar comparison. */
12673 if ((TREE_CODE (arg0) == COMPLEX_EXPR
12674 || TREE_CODE (arg0) == COMPLEX_CST)
12675 && (TREE_CODE (arg1) == COMPLEX_EXPR
12676 || TREE_CODE (arg1) == COMPLEX_CST))
12678 tree real0, imag0, real1, imag1;
12681 if (TREE_CODE (arg0) == COMPLEX_EXPR)
12683 real0 = TREE_OPERAND (arg0, 0);
12684 imag0 = TREE_OPERAND (arg0, 1);
12688 real0 = TREE_REALPART (arg0);
12689 imag0 = TREE_IMAGPART (arg0);
12692 if (TREE_CODE (arg1) == COMPLEX_EXPR)
12694 real1 = TREE_OPERAND (arg1, 0);
12695 imag1 = TREE_OPERAND (arg1, 1);
12699 real1 = TREE_REALPART (arg1);
12700 imag1 = TREE_IMAGPART (arg1);
12703 rcond = fold_binary_loc (loc, code, type, real0, real1);
12704 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
12706 if (integer_zerop (rcond))
12708 if (code == EQ_EXPR)
12709 return omit_two_operands_loc (loc, type, boolean_false_node,
12711 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
12715 if (code == NE_EXPR)
12716 return omit_two_operands_loc (loc, type, boolean_true_node,
12718 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
12722 icond = fold_binary_loc (loc, code, type, imag0, imag1);
12723 if (icond && TREE_CODE (icond) == INTEGER_CST)
12725 if (integer_zerop (icond))
12727 if (code == EQ_EXPR)
12728 return omit_two_operands_loc (loc, type, boolean_false_node,
12730 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
12734 if (code == NE_EXPR)
12735 return omit_two_operands_loc (loc, type, boolean_true_node,
12737 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
12748 tem = fold_comparison (loc, code, type, op0, op1);
12749 if (tem != NULL_TREE)
12752 /* Transform comparisons of the form X +- C CMP X. */
12753 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
12754 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12755 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
12756 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
12757 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12758 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
12760 tree arg01 = TREE_OPERAND (arg0, 1);
12761 enum tree_code code0 = TREE_CODE (arg0);
12764 if (TREE_CODE (arg01) == REAL_CST)
12765 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
12767 is_positive = tree_int_cst_sgn (arg01);
12769 /* (X - c) > X becomes false. */
12770 if (code == GT_EXPR
12771 && ((code0 == MINUS_EXPR && is_positive >= 0)
12772 || (code0 == PLUS_EXPR && is_positive <= 0)))
12774 if (TREE_CODE (arg01) == INTEGER_CST
12775 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12776 fold_overflow_warning (("assuming signed overflow does not "
12777 "occur when assuming that (X - c) > X "
12778 "is always false"),
12779 WARN_STRICT_OVERFLOW_ALL);
12780 return constant_boolean_node (0, type);
12783 /* Likewise (X + c) < X becomes false. */
12784 if (code == LT_EXPR
12785 && ((code0 == PLUS_EXPR && is_positive >= 0)
12786 || (code0 == MINUS_EXPR && is_positive <= 0)))
12788 if (TREE_CODE (arg01) == INTEGER_CST
12789 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12790 fold_overflow_warning (("assuming signed overflow does not "
12791 "occur when assuming that "
12792 "(X + c) < X is always false"),
12793 WARN_STRICT_OVERFLOW_ALL);
12794 return constant_boolean_node (0, type);
12797 /* Convert (X - c) <= X to true. */
12798 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12800 && ((code0 == MINUS_EXPR && is_positive >= 0)
12801 || (code0 == PLUS_EXPR && is_positive <= 0)))
12803 if (TREE_CODE (arg01) == INTEGER_CST
12804 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12805 fold_overflow_warning (("assuming signed overflow does not "
12806 "occur when assuming that "
12807 "(X - c) <= X is always true"),
12808 WARN_STRICT_OVERFLOW_ALL);
12809 return constant_boolean_node (1, type);
12812 /* Convert (X + c) >= X to true. */
12813 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
12815 && ((code0 == PLUS_EXPR && is_positive >= 0)
12816 || (code0 == MINUS_EXPR && is_positive <= 0)))
12818 if (TREE_CODE (arg01) == INTEGER_CST
12819 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12820 fold_overflow_warning (("assuming signed overflow does not "
12821 "occur when assuming that "
12822 "(X + c) >= X is always true"),
12823 WARN_STRICT_OVERFLOW_ALL);
12824 return constant_boolean_node (1, type);
12827 if (TREE_CODE (arg01) == INTEGER_CST)
12829 /* Convert X + c > X and X - c < X to true for integers. */
12830 if (code == GT_EXPR
12831 && ((code0 == PLUS_EXPR && is_positive > 0)
12832 || (code0 == MINUS_EXPR && is_positive < 0)))
12834 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12835 fold_overflow_warning (("assuming signed overflow does "
12836 "not occur when assuming that "
12837 "(X + c) > X is always true"),
12838 WARN_STRICT_OVERFLOW_ALL);
12839 return constant_boolean_node (1, type);
12842 if (code == LT_EXPR
12843 && ((code0 == MINUS_EXPR && is_positive > 0)
12844 || (code0 == PLUS_EXPR && is_positive < 0)))
12846 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12847 fold_overflow_warning (("assuming signed overflow does "
12848 "not occur when assuming that "
12849 "(X - c) < X is always true"),
12850 WARN_STRICT_OVERFLOW_ALL);
12851 return constant_boolean_node (1, type);
12854 /* Convert X + c <= X and X - c >= X to false for integers. */
12855 if (code == LE_EXPR
12856 && ((code0 == PLUS_EXPR && is_positive > 0)
12857 || (code0 == MINUS_EXPR && is_positive < 0)))
12859 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12860 fold_overflow_warning (("assuming signed overflow does "
12861 "not occur when assuming that "
12862 "(X + c) <= X is always false"),
12863 WARN_STRICT_OVERFLOW_ALL);
12864 return constant_boolean_node (0, type);
12867 if (code == GE_EXPR
12868 && ((code0 == MINUS_EXPR && is_positive > 0)
12869 || (code0 == PLUS_EXPR && is_positive < 0)))
12871 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
12872 fold_overflow_warning (("assuming signed overflow does "
12873 "not occur when assuming that "
12874 "(X - c) >= X is always false"),
12875 WARN_STRICT_OVERFLOW_ALL);
12876 return constant_boolean_node (0, type);
12881 /* Comparisons with the highest or lowest possible integer of
12882 the specified precision will have known values. */
12884 tree arg1_type = TREE_TYPE (arg1);
12885 unsigned int width = TYPE_PRECISION (arg1_type);
12887 if (TREE_CODE (arg1) == INTEGER_CST
12888 && width <= 2 * HOST_BITS_PER_WIDE_INT
12889 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
12891 HOST_WIDE_INT signed_max_hi;
12892 unsigned HOST_WIDE_INT signed_max_lo;
12893 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
12895 if (width <= HOST_BITS_PER_WIDE_INT)
12897 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12902 if (TYPE_UNSIGNED (arg1_type))
12904 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12910 max_lo = signed_max_lo;
12911 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12917 width -= HOST_BITS_PER_WIDE_INT;
12918 signed_max_lo = -1;
12919 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
12924 if (TYPE_UNSIGNED (arg1_type))
12926 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
12931 max_hi = signed_max_hi;
12932 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
12936 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
12937 && TREE_INT_CST_LOW (arg1) == max_lo)
12941 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12944 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12947 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12950 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
12952 /* The GE_EXPR and LT_EXPR cases above are not normally
12953 reached because of previous transformations. */
12958 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12960 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
12964 arg1 = const_binop (PLUS_EXPR, arg1,
12965 build_int_cst (TREE_TYPE (arg1), 1));
12966 return fold_build2_loc (loc, EQ_EXPR, type,
12967 fold_convert_loc (loc,
12968 TREE_TYPE (arg1), arg0),
12971 arg1 = const_binop (PLUS_EXPR, arg1,
12972 build_int_cst (TREE_TYPE (arg1), 1));
12973 return fold_build2_loc (loc, NE_EXPR, type,
12974 fold_convert_loc (loc, TREE_TYPE (arg1),
12980 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
12982 && TREE_INT_CST_LOW (arg1) == min_lo)
12986 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12989 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
12992 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12995 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13000 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13002 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13006 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13007 return fold_build2_loc (loc, NE_EXPR, type,
13008 fold_convert_loc (loc,
13009 TREE_TYPE (arg1), arg0),
13012 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node);
13013 return fold_build2_loc (loc, EQ_EXPR, type,
13014 fold_convert_loc (loc, TREE_TYPE (arg1),
13021 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13022 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13023 && TYPE_UNSIGNED (arg1_type)
13024 /* We will flip the signedness of the comparison operator
13025 associated with the mode of arg1, so the sign bit is
13026 specified by this mode. Check that arg1 is the signed
13027 max associated with this sign bit. */
13028 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13029 /* signed_type does not work on pointer types. */
13030 && INTEGRAL_TYPE_P (arg1_type))
13032 /* The following case also applies to X < signed_max+1
13033 and X >= signed_max+1 because previous transformations. */
13034 if (code == LE_EXPR || code == GT_EXPR)
13037 st = signed_type_for (TREE_TYPE (arg1));
13038 return fold_build2_loc (loc,
13039 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13040 type, fold_convert_loc (loc, st, arg0),
13041 build_int_cst (st, 0));
13047 /* If we are comparing an ABS_EXPR with a constant, we can
13048 convert all the cases into explicit comparisons, but they may
13049 well not be faster than doing the ABS and one comparison.
13050 But ABS (X) <= C is a range comparison, which becomes a subtraction
13051 and a comparison, and is probably faster. */
13052 if (code == LE_EXPR
13053 && TREE_CODE (arg1) == INTEGER_CST
13054 && TREE_CODE (arg0) == ABS_EXPR
13055 && ! TREE_SIDE_EFFECTS (arg0)
13056 && (0 != (tem = negate_expr (arg1)))
13057 && TREE_CODE (tem) == INTEGER_CST
13058 && !TREE_OVERFLOW (tem))
13059 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13060 build2 (GE_EXPR, type,
13061 TREE_OPERAND (arg0, 0), tem),
13062 build2 (LE_EXPR, type,
13063 TREE_OPERAND (arg0, 0), arg1));
13065 /* Convert ABS_EXPR<x> >= 0 to true. */
13066 strict_overflow_p = false;
13067 if (code == GE_EXPR
13068 && (integer_zerop (arg1)
13069 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13070 && real_zerop (arg1)))
13071 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13073 if (strict_overflow_p)
13074 fold_overflow_warning (("assuming signed overflow does not occur "
13075 "when simplifying comparison of "
13076 "absolute value and zero"),
13077 WARN_STRICT_OVERFLOW_CONDITIONAL);
13078 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13081 /* Convert ABS_EXPR<x> < 0 to false. */
13082 strict_overflow_p = false;
13083 if (code == LT_EXPR
13084 && (integer_zerop (arg1) || real_zerop (arg1))
13085 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13087 if (strict_overflow_p)
13088 fold_overflow_warning (("assuming signed overflow does not occur "
13089 "when simplifying comparison of "
13090 "absolute value and zero"),
13091 WARN_STRICT_OVERFLOW_CONDITIONAL);
13092 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13095 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13096 and similarly for >= into !=. */
13097 if ((code == LT_EXPR || code == GE_EXPR)
13098 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13099 && TREE_CODE (arg1) == LSHIFT_EXPR
13100 && integer_onep (TREE_OPERAND (arg1, 0)))
13102 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13103 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13104 TREE_OPERAND (arg1, 1)),
13105 build_int_cst (TREE_TYPE (arg0), 0));
13106 goto fold_binary_exit;
13109 if ((code == LT_EXPR || code == GE_EXPR)
13110 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13111 && CONVERT_EXPR_P (arg1)
13112 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13113 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13115 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13116 fold_convert_loc (loc, TREE_TYPE (arg0),
13117 build2 (RSHIFT_EXPR,
13118 TREE_TYPE (arg0), arg0,
13119 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13121 build_int_cst (TREE_TYPE (arg0), 0));
13122 goto fold_binary_exit;
13127 case UNORDERED_EXPR:
13135 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13137 t1 = fold_relational_const (code, type, arg0, arg1);
13138 if (t1 != NULL_TREE)
13142 /* If the first operand is NaN, the result is constant. */
13143 if (TREE_CODE (arg0) == REAL_CST
13144 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13145 && (code != LTGT_EXPR || ! flag_trapping_math))
13147 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13148 ? integer_zero_node
13149 : integer_one_node;
13150 return omit_one_operand_loc (loc, type, t1, arg1);
13153 /* If the second operand is NaN, the result is constant. */
13154 if (TREE_CODE (arg1) == REAL_CST
13155 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13156 && (code != LTGT_EXPR || ! flag_trapping_math))
13158 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13159 ? integer_zero_node
13160 : integer_one_node;
13161 return omit_one_operand_loc (loc, type, t1, arg0);
13164 /* Simplify unordered comparison of something with itself. */
13165 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13166 && operand_equal_p (arg0, arg1, 0))
13167 return constant_boolean_node (1, type);
13169 if (code == LTGT_EXPR
13170 && !flag_trapping_math
13171 && operand_equal_p (arg0, arg1, 0))
13172 return constant_boolean_node (0, type);
13174 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13176 tree targ0 = strip_float_extensions (arg0);
13177 tree targ1 = strip_float_extensions (arg1);
13178 tree newtype = TREE_TYPE (targ0);
13180 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13181 newtype = TREE_TYPE (targ1);
13183 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13184 return fold_build2_loc (loc, code, type,
13185 fold_convert_loc (loc, newtype, targ0),
13186 fold_convert_loc (loc, newtype, targ1));
13191 case COMPOUND_EXPR:
13192 /* When pedantic, a compound expression can be neither an lvalue
13193 nor an integer constant expression. */
13194 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13196 /* Don't let (0, 0) be null pointer constant. */
13197 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13198 : fold_convert_loc (loc, type, arg1);
13199 return pedantic_non_lvalue_loc (loc, tem);
13202 if ((TREE_CODE (arg0) == REAL_CST
13203 && TREE_CODE (arg1) == REAL_CST)
13204 || (TREE_CODE (arg0) == INTEGER_CST
13205 && TREE_CODE (arg1) == INTEGER_CST))
13206 return build_complex (type, arg0, arg1);
13210 /* An ASSERT_EXPR should never be passed to fold_binary. */
13211 gcc_unreachable ();
13215 } /* switch (code) */
13217 protected_set_expr_location (tem, loc);
13221 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13222 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13226 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13228 switch (TREE_CODE (*tp))
13234 *walk_subtrees = 0;
13236 /* ... fall through ... */
13243 /* Return whether the sub-tree ST contains a label which is accessible from
13244 outside the sub-tree. */
13247 contains_label_p (tree st)
13250 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13253 /* Fold a ternary expression of code CODE and type TYPE with operands
13254 OP0, OP1, and OP2. Return the folded expression if folding is
13255 successful. Otherwise, return NULL_TREE. */
13258 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13259 tree op0, tree op1, tree op2)
13262 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13263 enum tree_code_class kind = TREE_CODE_CLASS (code);
13265 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13266 && TREE_CODE_LENGTH (code) == 3);
13268 /* Strip any conversions that don't change the mode. This is safe
13269 for every expression, except for a comparison expression because
13270 its signedness is derived from its operands. So, in the latter
13271 case, only strip conversions that don't change the signedness.
13273 Note that this is done as an internal manipulation within the
13274 constant folder, in order to find the simplest representation of
13275 the arguments so that their form can be studied. In any cases,
13276 the appropriate type conversions should be put back in the tree
13277 that will get out of the constant folder. */
13292 case COMPONENT_REF:
13293 if (TREE_CODE (arg0) == CONSTRUCTOR
13294 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13296 unsigned HOST_WIDE_INT idx;
13298 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13305 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13306 so all simple results must be passed through pedantic_non_lvalue. */
13307 if (TREE_CODE (arg0) == INTEGER_CST)
13309 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13310 tem = integer_zerop (arg0) ? op2 : op1;
13311 /* Only optimize constant conditions when the selected branch
13312 has the same type as the COND_EXPR. This avoids optimizing
13313 away "c ? x : throw", where the throw has a void type.
13314 Avoid throwing away that operand which contains label. */
13315 if ((!TREE_SIDE_EFFECTS (unused_op)
13316 || !contains_label_p (unused_op))
13317 && (! VOID_TYPE_P (TREE_TYPE (tem))
13318 || VOID_TYPE_P (type)))
13319 return pedantic_non_lvalue_loc (loc, tem);
13322 if (operand_equal_p (arg1, op2, 0))
13323 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13325 /* If we have A op B ? A : C, we may be able to convert this to a
13326 simpler expression, depending on the operation and the values
13327 of B and C. Signed zeros prevent all of these transformations,
13328 for reasons given above each one.
13330 Also try swapping the arguments and inverting the conditional. */
13331 if (COMPARISON_CLASS_P (arg0)
13332 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13333 arg1, TREE_OPERAND (arg0, 1))
13334 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13336 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13341 if (COMPARISON_CLASS_P (arg0)
13342 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13344 TREE_OPERAND (arg0, 1))
13345 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13347 tem = fold_truth_not_expr (loc, arg0);
13348 if (tem && COMPARISON_CLASS_P (tem))
13350 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13356 /* If the second operand is simpler than the third, swap them
13357 since that produces better jump optimization results. */
13358 if (truth_value_p (TREE_CODE (arg0))
13359 && tree_swap_operands_p (op1, op2, false))
13361 /* See if this can be inverted. If it can't, possibly because
13362 it was a floating-point inequality comparison, don't do
13364 tem = fold_truth_not_expr (loc, arg0);
13366 return fold_build3_loc (loc, code, type, tem, op2, op1);
13369 /* Convert A ? 1 : 0 to simply A. */
13370 if (integer_onep (op1)
13371 && integer_zerop (op2)
13372 /* If we try to convert OP0 to our type, the
13373 call to fold will try to move the conversion inside
13374 a COND, which will recurse. In that case, the COND_EXPR
13375 is probably the best choice, so leave it alone. */
13376 && type == TREE_TYPE (arg0))
13377 return pedantic_non_lvalue_loc (loc, arg0);
13379 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13380 over COND_EXPR in cases such as floating point comparisons. */
13381 if (integer_zerop (op1)
13382 && integer_onep (op2)
13383 && truth_value_p (TREE_CODE (arg0)))
13384 return pedantic_non_lvalue_loc (loc,
13385 fold_convert_loc (loc, type,
13386 invert_truthvalue_loc (loc,
13389 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13390 if (TREE_CODE (arg0) == LT_EXPR
13391 && integer_zerop (TREE_OPERAND (arg0, 1))
13392 && integer_zerop (op2)
13393 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13395 /* sign_bit_p only checks ARG1 bits within A's precision.
13396 If <sign bit of A> has wider type than A, bits outside
13397 of A's precision in <sign bit of A> need to be checked.
13398 If they are all 0, this optimization needs to be done
13399 in unsigned A's type, if they are all 1 in signed A's type,
13400 otherwise this can't be done. */
13401 if (TYPE_PRECISION (TREE_TYPE (tem))
13402 < TYPE_PRECISION (TREE_TYPE (arg1))
13403 && TYPE_PRECISION (TREE_TYPE (tem))
13404 < TYPE_PRECISION (type))
13406 unsigned HOST_WIDE_INT mask_lo;
13407 HOST_WIDE_INT mask_hi;
13408 int inner_width, outer_width;
13411 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13412 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13413 if (outer_width > TYPE_PRECISION (type))
13414 outer_width = TYPE_PRECISION (type);
13416 if (outer_width > HOST_BITS_PER_WIDE_INT)
13418 mask_hi = ((unsigned HOST_WIDE_INT) -1
13419 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13425 mask_lo = ((unsigned HOST_WIDE_INT) -1
13426 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13428 if (inner_width > HOST_BITS_PER_WIDE_INT)
13430 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13431 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13435 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13436 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13438 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13439 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13441 tem_type = signed_type_for (TREE_TYPE (tem));
13442 tem = fold_convert_loc (loc, tem_type, tem);
13444 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13445 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13447 tem_type = unsigned_type_for (TREE_TYPE (tem));
13448 tem = fold_convert_loc (loc, tem_type, tem);
13456 fold_convert_loc (loc, type,
13457 fold_build2_loc (loc, BIT_AND_EXPR,
13458 TREE_TYPE (tem), tem,
13459 fold_convert_loc (loc,
13464 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13465 already handled above. */
13466 if (TREE_CODE (arg0) == BIT_AND_EXPR
13467 && integer_onep (TREE_OPERAND (arg0, 1))
13468 && integer_zerop (op2)
13469 && integer_pow2p (arg1))
13471 tree tem = TREE_OPERAND (arg0, 0);
13473 if (TREE_CODE (tem) == RSHIFT_EXPR
13474 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13475 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13476 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13477 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13478 TREE_OPERAND (tem, 0), arg1);
13481 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13482 is probably obsolete because the first operand should be a
13483 truth value (that's why we have the two cases above), but let's
13484 leave it in until we can confirm this for all front-ends. */
13485 if (integer_zerop (op2)
13486 && TREE_CODE (arg0) == NE_EXPR
13487 && integer_zerop (TREE_OPERAND (arg0, 1))
13488 && integer_pow2p (arg1)
13489 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13490 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13491 arg1, OEP_ONLY_CONST))
13492 return pedantic_non_lvalue_loc (loc,
13493 fold_convert_loc (loc, type,
13494 TREE_OPERAND (arg0, 0)));
13496 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13497 if (integer_zerop (op2)
13498 && truth_value_p (TREE_CODE (arg0))
13499 && truth_value_p (TREE_CODE (arg1)))
13500 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13501 fold_convert_loc (loc, type, arg0),
13504 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13505 if (integer_onep (op2)
13506 && truth_value_p (TREE_CODE (arg0))
13507 && truth_value_p (TREE_CODE (arg1)))
13509 /* Only perform transformation if ARG0 is easily inverted. */
13510 tem = fold_truth_not_expr (loc, arg0);
13512 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13513 fold_convert_loc (loc, type, tem),
13517 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13518 if (integer_zerop (arg1)
13519 && truth_value_p (TREE_CODE (arg0))
13520 && truth_value_p (TREE_CODE (op2)))
13522 /* Only perform transformation if ARG0 is easily inverted. */
13523 tem = fold_truth_not_expr (loc, arg0);
13525 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13526 fold_convert_loc (loc, type, tem),
13530 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13531 if (integer_onep (arg1)
13532 && truth_value_p (TREE_CODE (arg0))
13533 && truth_value_p (TREE_CODE (op2)))
13534 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13535 fold_convert_loc (loc, type, arg0),
13541 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13542 of fold_ternary on them. */
13543 gcc_unreachable ();
13545 case BIT_FIELD_REF:
13546 if ((TREE_CODE (arg0) == VECTOR_CST
13547 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13548 && type == TREE_TYPE (TREE_TYPE (arg0)))
13550 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
13551 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
13554 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
13555 && (idx % width) == 0
13556 && (idx = idx / width)
13557 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
13559 tree elements = NULL_TREE;
13561 if (TREE_CODE (arg0) == VECTOR_CST)
13562 elements = TREE_VECTOR_CST_ELTS (arg0);
13565 unsigned HOST_WIDE_INT idx;
13568 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
13569 elements = tree_cons (NULL_TREE, value, elements);
13571 while (idx-- > 0 && elements)
13572 elements = TREE_CHAIN (elements);
13574 return TREE_VALUE (elements);
13576 return fold_convert_loc (loc, type, integer_zero_node);
13580 /* A bit-field-ref that referenced the full argument can be stripped. */
13581 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
13582 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
13583 && integer_zerop (op2))
13584 return fold_convert_loc (loc, type, arg0);
13590 } /* switch (code) */
13593 /* Perform constant folding and related simplification of EXPR.
13594 The related simplifications include x*1 => x, x*0 => 0, etc.,
13595 and application of the associative law.
13596 NOP_EXPR conversions may be removed freely (as long as we
13597 are careful not to change the type of the overall expression).
13598 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
13599 but we can constant-fold them if they have constant operands. */
13601 #ifdef ENABLE_FOLD_CHECKING
13602 # define fold(x) fold_1 (x)
13603 static tree fold_1 (tree);
13609 const tree t = expr;
13610 enum tree_code code = TREE_CODE (t);
13611 enum tree_code_class kind = TREE_CODE_CLASS (code);
13613 location_t loc = EXPR_LOCATION (expr);
13615 /* Return right away if a constant. */
13616 if (kind == tcc_constant)
13619 /* CALL_EXPR-like objects with variable numbers of operands are
13620 treated specially. */
13621 if (kind == tcc_vl_exp)
13623 if (code == CALL_EXPR)
13625 tem = fold_call_expr (loc, expr, false);
13626 return tem ? tem : expr;
13631 if (IS_EXPR_CODE_CLASS (kind))
13633 tree type = TREE_TYPE (t);
13634 tree op0, op1, op2;
13636 switch (TREE_CODE_LENGTH (code))
13639 op0 = TREE_OPERAND (t, 0);
13640 tem = fold_unary_loc (loc, code, type, op0);
13641 return tem ? tem : expr;
13643 op0 = TREE_OPERAND (t, 0);
13644 op1 = TREE_OPERAND (t, 1);
13645 tem = fold_binary_loc (loc, code, type, op0, op1);
13646 return tem ? tem : expr;
13648 op0 = TREE_OPERAND (t, 0);
13649 op1 = TREE_OPERAND (t, 1);
13650 op2 = TREE_OPERAND (t, 2);
13651 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
13652 return tem ? tem : expr;
13662 tree op0 = TREE_OPERAND (t, 0);
13663 tree op1 = TREE_OPERAND (t, 1);
13665 if (TREE_CODE (op1) == INTEGER_CST
13666 && TREE_CODE (op0) == CONSTRUCTOR
13667 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
13669 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
13670 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
13671 unsigned HOST_WIDE_INT begin = 0;
13673 /* Find a matching index by means of a binary search. */
13674 while (begin != end)
13676 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
13677 tree index = VEC_index (constructor_elt, elts, middle)->index;
13679 if (TREE_CODE (index) == INTEGER_CST
13680 && tree_int_cst_lt (index, op1))
13681 begin = middle + 1;
13682 else if (TREE_CODE (index) == INTEGER_CST
13683 && tree_int_cst_lt (op1, index))
13685 else if (TREE_CODE (index) == RANGE_EXPR
13686 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
13687 begin = middle + 1;
13688 else if (TREE_CODE (index) == RANGE_EXPR
13689 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
13692 return VEC_index (constructor_elt, elts, middle)->value;
13700 return fold (DECL_INITIAL (t));
13704 } /* switch (code) */
13707 #ifdef ENABLE_FOLD_CHECKING
13710 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
13711 static void fold_check_failed (const_tree, const_tree);
13712 void print_fold_checksum (const_tree);
13714 /* When --enable-checking=fold, compute a digest of expr before
13715 and after actual fold call to see if fold did not accidentally
13716 change original expr. */
13722 struct md5_ctx ctx;
13723 unsigned char checksum_before[16], checksum_after[16];
13726 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13727 md5_init_ctx (&ctx);
13728 fold_checksum_tree (expr, &ctx, ht);
13729 md5_finish_ctx (&ctx, checksum_before);
13732 ret = fold_1 (expr);
13734 md5_init_ctx (&ctx);
13735 fold_checksum_tree (expr, &ctx, ht);
13736 md5_finish_ctx (&ctx, checksum_after);
13739 if (memcmp (checksum_before, checksum_after, 16))
13740 fold_check_failed (expr, ret);
13746 print_fold_checksum (const_tree expr)
13748 struct md5_ctx ctx;
13749 unsigned char checksum[16], cnt;
13752 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13753 md5_init_ctx (&ctx);
13754 fold_checksum_tree (expr, &ctx, ht);
13755 md5_finish_ctx (&ctx, checksum);
13757 for (cnt = 0; cnt < 16; ++cnt)
13758 fprintf (stderr, "%02x", checksum[cnt]);
13759 putc ('\n', stderr);
13763 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
13765 internal_error ("fold check: original tree changed by fold");
13769 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
13772 enum tree_code code;
13773 union tree_node buf;
13778 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
13779 <= sizeof (struct tree_function_decl))
13780 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
13783 slot = (void **) htab_find_slot (ht, expr, INSERT);
13786 *slot = CONST_CAST_TREE (expr);
13787 code = TREE_CODE (expr);
13788 if (TREE_CODE_CLASS (code) == tcc_declaration
13789 && DECL_ASSEMBLER_NAME_SET_P (expr))
13791 /* Allow DECL_ASSEMBLER_NAME to be modified. */
13792 memcpy ((char *) &buf, expr, tree_size (expr));
13793 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
13794 expr = (tree) &buf;
13796 else if (TREE_CODE_CLASS (code) == tcc_type
13797 && (TYPE_POINTER_TO (expr)
13798 || TYPE_REFERENCE_TO (expr)
13799 || TYPE_CACHED_VALUES_P (expr)
13800 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
13801 || TYPE_NEXT_VARIANT (expr)))
13803 /* Allow these fields to be modified. */
13805 memcpy ((char *) &buf, expr, tree_size (expr));
13806 expr = tmp = (tree) &buf;
13807 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
13808 TYPE_POINTER_TO (tmp) = NULL;
13809 TYPE_REFERENCE_TO (tmp) = NULL;
13810 TYPE_NEXT_VARIANT (tmp) = NULL;
13811 if (TYPE_CACHED_VALUES_P (tmp))
13813 TYPE_CACHED_VALUES_P (tmp) = 0;
13814 TYPE_CACHED_VALUES (tmp) = NULL;
13817 md5_process_bytes (expr, tree_size (expr), ctx);
13818 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
13819 if (TREE_CODE_CLASS (code) != tcc_type
13820 && TREE_CODE_CLASS (code) != tcc_declaration
13821 && code != TREE_LIST
13822 && code != SSA_NAME)
13823 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
13824 switch (TREE_CODE_CLASS (code))
13830 md5_process_bytes (TREE_STRING_POINTER (expr),
13831 TREE_STRING_LENGTH (expr), ctx);
13834 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
13835 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
13838 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
13844 case tcc_exceptional:
13848 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
13849 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
13850 expr = TREE_CHAIN (expr);
13851 goto recursive_label;
13854 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
13855 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
13861 case tcc_expression:
13862 case tcc_reference:
13863 case tcc_comparison:
13866 case tcc_statement:
13868 len = TREE_OPERAND_LENGTH (expr);
13869 for (i = 0; i < len; ++i)
13870 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
13872 case tcc_declaration:
13873 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
13874 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
13875 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
13877 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
13878 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
13879 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
13880 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
13881 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
13883 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
13884 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
13886 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
13888 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
13889 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
13890 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
13894 if (TREE_CODE (expr) == ENUMERAL_TYPE)
13895 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
13896 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
13897 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
13898 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
13899 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
13900 if (INTEGRAL_TYPE_P (expr)
13901 || SCALAR_FLOAT_TYPE_P (expr))
13903 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
13904 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
13906 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
13907 if (TREE_CODE (expr) == RECORD_TYPE
13908 || TREE_CODE (expr) == UNION_TYPE
13909 || TREE_CODE (expr) == QUAL_UNION_TYPE)
13910 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
13911 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
13918 /* Helper function for outputting the checksum of a tree T. When
13919 debugging with gdb, you can "define mynext" to be "next" followed
13920 by "call debug_fold_checksum (op0)", then just trace down till the
13923 DEBUG_FUNCTION void
13924 debug_fold_checksum (const_tree t)
13927 unsigned char checksum[16];
13928 struct md5_ctx ctx;
13929 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13931 md5_init_ctx (&ctx);
13932 fold_checksum_tree (t, &ctx, ht);
13933 md5_finish_ctx (&ctx, checksum);
13936 for (i = 0; i < 16; i++)
13937 fprintf (stderr, "%d ", checksum[i]);
13939 fprintf (stderr, "\n");
13944 /* Fold a unary tree expression with code CODE of type TYPE with an
13945 operand OP0. LOC is the location of the resulting expression.
13946 Return a folded expression if successful. Otherwise, return a tree
13947 expression with code CODE of type TYPE with an operand OP0. */
13950 fold_build1_stat_loc (location_t loc,
13951 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
13954 #ifdef ENABLE_FOLD_CHECKING
13955 unsigned char checksum_before[16], checksum_after[16];
13956 struct md5_ctx ctx;
13959 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
13960 md5_init_ctx (&ctx);
13961 fold_checksum_tree (op0, &ctx, ht);
13962 md5_finish_ctx (&ctx, checksum_before);
13966 tem = fold_unary_loc (loc, code, type, op0);
13969 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
13970 SET_EXPR_LOCATION (tem, loc);
13973 #ifdef ENABLE_FOLD_CHECKING
13974 md5_init_ctx (&ctx);
13975 fold_checksum_tree (op0, &ctx, ht);
13976 md5_finish_ctx (&ctx, checksum_after);
13979 if (memcmp (checksum_before, checksum_after, 16))
13980 fold_check_failed (op0, tem);
13985 /* Fold a binary tree expression with code CODE of type TYPE with
13986 operands OP0 and OP1. LOC is the location of the resulting
13987 expression. Return a folded expression if successful. Otherwise,
13988 return a tree expression with code CODE of type TYPE with operands
13992 fold_build2_stat_loc (location_t loc,
13993 enum tree_code code, tree type, tree op0, tree op1
13997 #ifdef ENABLE_FOLD_CHECKING
13998 unsigned char checksum_before_op0[16],
13999 checksum_before_op1[16],
14000 checksum_after_op0[16],
14001 checksum_after_op1[16];
14002 struct md5_ctx ctx;
14005 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14006 md5_init_ctx (&ctx);
14007 fold_checksum_tree (op0, &ctx, ht);
14008 md5_finish_ctx (&ctx, checksum_before_op0);
14011 md5_init_ctx (&ctx);
14012 fold_checksum_tree (op1, &ctx, ht);
14013 md5_finish_ctx (&ctx, checksum_before_op1);
14017 tem = fold_binary_loc (loc, code, type, op0, op1);
14020 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
14021 SET_EXPR_LOCATION (tem, loc);
14024 #ifdef ENABLE_FOLD_CHECKING
14025 md5_init_ctx (&ctx);
14026 fold_checksum_tree (op0, &ctx, ht);
14027 md5_finish_ctx (&ctx, checksum_after_op0);
14030 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14031 fold_check_failed (op0, tem);
14033 md5_init_ctx (&ctx);
14034 fold_checksum_tree (op1, &ctx, ht);
14035 md5_finish_ctx (&ctx, checksum_after_op1);
14038 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14039 fold_check_failed (op1, tem);
14044 /* Fold a ternary tree expression with code CODE of type TYPE with
14045 operands OP0, OP1, and OP2. Return a folded expression if
14046 successful. Otherwise, return a tree expression with code CODE of
14047 type TYPE with operands OP0, OP1, and OP2. */
14050 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14051 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14054 #ifdef ENABLE_FOLD_CHECKING
14055 unsigned char checksum_before_op0[16],
14056 checksum_before_op1[16],
14057 checksum_before_op2[16],
14058 checksum_after_op0[16],
14059 checksum_after_op1[16],
14060 checksum_after_op2[16];
14061 struct md5_ctx ctx;
14064 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14065 md5_init_ctx (&ctx);
14066 fold_checksum_tree (op0, &ctx, ht);
14067 md5_finish_ctx (&ctx, checksum_before_op0);
14070 md5_init_ctx (&ctx);
14071 fold_checksum_tree (op1, &ctx, ht);
14072 md5_finish_ctx (&ctx, checksum_before_op1);
14075 md5_init_ctx (&ctx);
14076 fold_checksum_tree (op2, &ctx, ht);
14077 md5_finish_ctx (&ctx, checksum_before_op2);
14081 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14082 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14085 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
14086 SET_EXPR_LOCATION (tem, loc);
14089 #ifdef ENABLE_FOLD_CHECKING
14090 md5_init_ctx (&ctx);
14091 fold_checksum_tree (op0, &ctx, ht);
14092 md5_finish_ctx (&ctx, checksum_after_op0);
14095 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14096 fold_check_failed (op0, tem);
14098 md5_init_ctx (&ctx);
14099 fold_checksum_tree (op1, &ctx, ht);
14100 md5_finish_ctx (&ctx, checksum_after_op1);
14103 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14104 fold_check_failed (op1, tem);
14106 md5_init_ctx (&ctx);
14107 fold_checksum_tree (op2, &ctx, ht);
14108 md5_finish_ctx (&ctx, checksum_after_op2);
14111 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14112 fold_check_failed (op2, tem);
14117 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14118 arguments in ARGARRAY, and a null static chain.
14119 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14120 of type TYPE from the given operands as constructed by build_call_array. */
14123 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14124 int nargs, tree *argarray)
14127 #ifdef ENABLE_FOLD_CHECKING
14128 unsigned char checksum_before_fn[16],
14129 checksum_before_arglist[16],
14130 checksum_after_fn[16],
14131 checksum_after_arglist[16];
14132 struct md5_ctx ctx;
14136 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14137 md5_init_ctx (&ctx);
14138 fold_checksum_tree (fn, &ctx, ht);
14139 md5_finish_ctx (&ctx, checksum_before_fn);
14142 md5_init_ctx (&ctx);
14143 for (i = 0; i < nargs; i++)
14144 fold_checksum_tree (argarray[i], &ctx, ht);
14145 md5_finish_ctx (&ctx, checksum_before_arglist);
14149 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14151 #ifdef ENABLE_FOLD_CHECKING
14152 md5_init_ctx (&ctx);
14153 fold_checksum_tree (fn, &ctx, ht);
14154 md5_finish_ctx (&ctx, checksum_after_fn);
14157 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14158 fold_check_failed (fn, tem);
14160 md5_init_ctx (&ctx);
14161 for (i = 0; i < nargs; i++)
14162 fold_checksum_tree (argarray[i], &ctx, ht);
14163 md5_finish_ctx (&ctx, checksum_after_arglist);
14166 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14167 fold_check_failed (NULL_TREE, tem);
14172 /* Perform constant folding and related simplification of initializer
14173 expression EXPR. These behave identically to "fold_buildN" but ignore
14174 potential run-time traps and exceptions that fold must preserve. */
14176 #define START_FOLD_INIT \
14177 int saved_signaling_nans = flag_signaling_nans;\
14178 int saved_trapping_math = flag_trapping_math;\
14179 int saved_rounding_math = flag_rounding_math;\
14180 int saved_trapv = flag_trapv;\
14181 int saved_folding_initializer = folding_initializer;\
14182 flag_signaling_nans = 0;\
14183 flag_trapping_math = 0;\
14184 flag_rounding_math = 0;\
14186 folding_initializer = 1;
14188 #define END_FOLD_INIT \
14189 flag_signaling_nans = saved_signaling_nans;\
14190 flag_trapping_math = saved_trapping_math;\
14191 flag_rounding_math = saved_rounding_math;\
14192 flag_trapv = saved_trapv;\
14193 folding_initializer = saved_folding_initializer;
14196 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14197 tree type, tree op)
14202 result = fold_build1_loc (loc, code, type, op);
14209 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14210 tree type, tree op0, tree op1)
14215 result = fold_build2_loc (loc, code, type, op0, op1);
14222 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14223 tree type, tree op0, tree op1, tree op2)
14228 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14235 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14236 int nargs, tree *argarray)
14241 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14247 #undef START_FOLD_INIT
14248 #undef END_FOLD_INIT
14250 /* Determine if first argument is a multiple of second argument. Return 0 if
14251 it is not, or we cannot easily determined it to be.
14253 An example of the sort of thing we care about (at this point; this routine
14254 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14255 fold cases do now) is discovering that
14257 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14263 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14265 This code also handles discovering that
14267 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14269 is a multiple of 8 so we don't have to worry about dealing with a
14270 possible remainder.
14272 Note that we *look* inside a SAVE_EXPR only to determine how it was
14273 calculated; it is not safe for fold to do much of anything else with the
14274 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14275 at run time. For example, the latter example above *cannot* be implemented
14276 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14277 evaluation time of the original SAVE_EXPR is not necessarily the same at
14278 the time the new expression is evaluated. The only optimization of this
14279 sort that would be valid is changing
14281 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14285 SAVE_EXPR (I) * SAVE_EXPR (J)
14287 (where the same SAVE_EXPR (J) is used in the original and the
14288 transformed version). */
14291 multiple_of_p (tree type, const_tree top, const_tree bottom)
14293 if (operand_equal_p (top, bottom, 0))
14296 if (TREE_CODE (type) != INTEGER_TYPE)
14299 switch (TREE_CODE (top))
14302 /* Bitwise and provides a power of two multiple. If the mask is
14303 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14304 if (!integer_pow2p (bottom))
14309 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14310 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14314 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14315 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14318 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14322 op1 = TREE_OPERAND (top, 1);
14323 /* const_binop may not detect overflow correctly,
14324 so check for it explicitly here. */
14325 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14326 > TREE_INT_CST_LOW (op1)
14327 && TREE_INT_CST_HIGH (op1) == 0
14328 && 0 != (t1 = fold_convert (type,
14329 const_binop (LSHIFT_EXPR,
14332 && !TREE_OVERFLOW (t1))
14333 return multiple_of_p (type, t1, bottom);
14338 /* Can't handle conversions from non-integral or wider integral type. */
14339 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14340 || (TYPE_PRECISION (type)
14341 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14344 /* .. fall through ... */
14347 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14350 return (multiple_of_p (type, TREE_OPERAND (top, 1), bottom)
14351 && multiple_of_p (type, TREE_OPERAND (top, 2), bottom));
14354 if (TREE_CODE (bottom) != INTEGER_CST
14355 || integer_zerop (bottom)
14356 || (TYPE_UNSIGNED (type)
14357 && (tree_int_cst_sgn (top) < 0
14358 || tree_int_cst_sgn (bottom) < 0)))
14360 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14368 /* Return true if CODE or TYPE is known to be non-negative. */
14371 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14373 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14374 && truth_value_p (code))
14375 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14376 have a signed:1 type (where the value is -1 and 0). */
14381 /* Return true if (CODE OP0) is known to be non-negative. If the return
14382 value is based on the assumption that signed overflow is undefined,
14383 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14384 *STRICT_OVERFLOW_P. */
14387 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14388 bool *strict_overflow_p)
14390 if (TYPE_UNSIGNED (type))
14396 /* We can't return 1 if flag_wrapv is set because
14397 ABS_EXPR<INT_MIN> = INT_MIN. */
14398 if (!INTEGRAL_TYPE_P (type))
14400 if (TYPE_OVERFLOW_UNDEFINED (type))
14402 *strict_overflow_p = true;
14407 case NON_LVALUE_EXPR:
14409 case FIX_TRUNC_EXPR:
14410 return tree_expr_nonnegative_warnv_p (op0,
14411 strict_overflow_p);
14415 tree inner_type = TREE_TYPE (op0);
14416 tree outer_type = type;
14418 if (TREE_CODE (outer_type) == REAL_TYPE)
14420 if (TREE_CODE (inner_type) == REAL_TYPE)
14421 return tree_expr_nonnegative_warnv_p (op0,
14422 strict_overflow_p);
14423 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14425 if (TYPE_UNSIGNED (inner_type))
14427 return tree_expr_nonnegative_warnv_p (op0,
14428 strict_overflow_p);
14431 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14433 if (TREE_CODE (inner_type) == REAL_TYPE)
14434 return tree_expr_nonnegative_warnv_p (op0,
14435 strict_overflow_p);
14436 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14437 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14438 && TYPE_UNSIGNED (inner_type);
14444 return tree_simple_nonnegative_warnv_p (code, type);
14447 /* We don't know sign of `t', so be conservative and return false. */
14451 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14452 value is based on the assumption that signed overflow is undefined,
14453 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14454 *STRICT_OVERFLOW_P. */
14457 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14458 tree op1, bool *strict_overflow_p)
14460 if (TYPE_UNSIGNED (type))
14465 case POINTER_PLUS_EXPR:
14467 if (FLOAT_TYPE_P (type))
14468 return (tree_expr_nonnegative_warnv_p (op0,
14470 && tree_expr_nonnegative_warnv_p (op1,
14471 strict_overflow_p));
14473 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14474 both unsigned and at least 2 bits shorter than the result. */
14475 if (TREE_CODE (type) == INTEGER_TYPE
14476 && TREE_CODE (op0) == NOP_EXPR
14477 && TREE_CODE (op1) == NOP_EXPR)
14479 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14480 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14481 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14482 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14484 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14485 TYPE_PRECISION (inner2)) + 1;
14486 return prec < TYPE_PRECISION (type);
14492 if (FLOAT_TYPE_P (type))
14494 /* x * x for floating point x is always non-negative. */
14495 if (operand_equal_p (op0, op1, 0))
14497 return (tree_expr_nonnegative_warnv_p (op0,
14499 && tree_expr_nonnegative_warnv_p (op1,
14500 strict_overflow_p));
14503 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14504 both unsigned and their total bits is shorter than the result. */
14505 if (TREE_CODE (type) == INTEGER_TYPE
14506 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14507 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14509 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14510 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14512 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14513 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14516 bool unsigned0 = TYPE_UNSIGNED (inner0);
14517 bool unsigned1 = TYPE_UNSIGNED (inner1);
14519 if (TREE_CODE (op0) == INTEGER_CST)
14520 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14522 if (TREE_CODE (op1) == INTEGER_CST)
14523 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14525 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14526 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14528 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14529 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14530 : TYPE_PRECISION (inner0);
14532 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14533 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14534 : TYPE_PRECISION (inner1);
14536 return precision0 + precision1 < TYPE_PRECISION (type);
14543 return (tree_expr_nonnegative_warnv_p (op0,
14545 || tree_expr_nonnegative_warnv_p (op1,
14546 strict_overflow_p));
14552 case TRUNC_DIV_EXPR:
14553 case CEIL_DIV_EXPR:
14554 case FLOOR_DIV_EXPR:
14555 case ROUND_DIV_EXPR:
14556 return (tree_expr_nonnegative_warnv_p (op0,
14558 && tree_expr_nonnegative_warnv_p (op1,
14559 strict_overflow_p));
14561 case TRUNC_MOD_EXPR:
14562 case CEIL_MOD_EXPR:
14563 case FLOOR_MOD_EXPR:
14564 case ROUND_MOD_EXPR:
14565 return tree_expr_nonnegative_warnv_p (op0,
14566 strict_overflow_p);
14568 return tree_simple_nonnegative_warnv_p (code, type);
14571 /* We don't know sign of `t', so be conservative and return false. */
14575 /* Return true if T is known to be non-negative. If the return
14576 value is based on the assumption that signed overflow is undefined,
14577 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14578 *STRICT_OVERFLOW_P. */
14581 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14583 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14586 switch (TREE_CODE (t))
14589 return tree_int_cst_sgn (t) >= 0;
14592 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
14595 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
14598 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14600 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
14601 strict_overflow_p));
14603 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14606 /* We don't know sign of `t', so be conservative and return false. */
14610 /* Return true if T is known to be non-negative. If the return
14611 value is based on the assumption that signed overflow is undefined,
14612 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14613 *STRICT_OVERFLOW_P. */
14616 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
14617 tree arg0, tree arg1, bool *strict_overflow_p)
14619 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
14620 switch (DECL_FUNCTION_CODE (fndecl))
14622 CASE_FLT_FN (BUILT_IN_ACOS):
14623 CASE_FLT_FN (BUILT_IN_ACOSH):
14624 CASE_FLT_FN (BUILT_IN_CABS):
14625 CASE_FLT_FN (BUILT_IN_COSH):
14626 CASE_FLT_FN (BUILT_IN_ERFC):
14627 CASE_FLT_FN (BUILT_IN_EXP):
14628 CASE_FLT_FN (BUILT_IN_EXP10):
14629 CASE_FLT_FN (BUILT_IN_EXP2):
14630 CASE_FLT_FN (BUILT_IN_FABS):
14631 CASE_FLT_FN (BUILT_IN_FDIM):
14632 CASE_FLT_FN (BUILT_IN_HYPOT):
14633 CASE_FLT_FN (BUILT_IN_POW10):
14634 CASE_INT_FN (BUILT_IN_FFS):
14635 CASE_INT_FN (BUILT_IN_PARITY):
14636 CASE_INT_FN (BUILT_IN_POPCOUNT):
14637 case BUILT_IN_BSWAP32:
14638 case BUILT_IN_BSWAP64:
14642 CASE_FLT_FN (BUILT_IN_SQRT):
14643 /* sqrt(-0.0) is -0.0. */
14644 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
14646 return tree_expr_nonnegative_warnv_p (arg0,
14647 strict_overflow_p);
14649 CASE_FLT_FN (BUILT_IN_ASINH):
14650 CASE_FLT_FN (BUILT_IN_ATAN):
14651 CASE_FLT_FN (BUILT_IN_ATANH):
14652 CASE_FLT_FN (BUILT_IN_CBRT):
14653 CASE_FLT_FN (BUILT_IN_CEIL):
14654 CASE_FLT_FN (BUILT_IN_ERF):
14655 CASE_FLT_FN (BUILT_IN_EXPM1):
14656 CASE_FLT_FN (BUILT_IN_FLOOR):
14657 CASE_FLT_FN (BUILT_IN_FMOD):
14658 CASE_FLT_FN (BUILT_IN_FREXP):
14659 CASE_FLT_FN (BUILT_IN_LCEIL):
14660 CASE_FLT_FN (BUILT_IN_LDEXP):
14661 CASE_FLT_FN (BUILT_IN_LFLOOR):
14662 CASE_FLT_FN (BUILT_IN_LLCEIL):
14663 CASE_FLT_FN (BUILT_IN_LLFLOOR):
14664 CASE_FLT_FN (BUILT_IN_LLRINT):
14665 CASE_FLT_FN (BUILT_IN_LLROUND):
14666 CASE_FLT_FN (BUILT_IN_LRINT):
14667 CASE_FLT_FN (BUILT_IN_LROUND):
14668 CASE_FLT_FN (BUILT_IN_MODF):
14669 CASE_FLT_FN (BUILT_IN_NEARBYINT):
14670 CASE_FLT_FN (BUILT_IN_RINT):
14671 CASE_FLT_FN (BUILT_IN_ROUND):
14672 CASE_FLT_FN (BUILT_IN_SCALB):
14673 CASE_FLT_FN (BUILT_IN_SCALBLN):
14674 CASE_FLT_FN (BUILT_IN_SCALBN):
14675 CASE_FLT_FN (BUILT_IN_SIGNBIT):
14676 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
14677 CASE_FLT_FN (BUILT_IN_SINH):
14678 CASE_FLT_FN (BUILT_IN_TANH):
14679 CASE_FLT_FN (BUILT_IN_TRUNC):
14680 /* True if the 1st argument is nonnegative. */
14681 return tree_expr_nonnegative_warnv_p (arg0,
14682 strict_overflow_p);
14684 CASE_FLT_FN (BUILT_IN_FMAX):
14685 /* True if the 1st OR 2nd arguments are nonnegative. */
14686 return (tree_expr_nonnegative_warnv_p (arg0,
14688 || (tree_expr_nonnegative_warnv_p (arg1,
14689 strict_overflow_p)));
14691 CASE_FLT_FN (BUILT_IN_FMIN):
14692 /* True if the 1st AND 2nd arguments are nonnegative. */
14693 return (tree_expr_nonnegative_warnv_p (arg0,
14695 && (tree_expr_nonnegative_warnv_p (arg1,
14696 strict_overflow_p)));
14698 CASE_FLT_FN (BUILT_IN_COPYSIGN):
14699 /* True if the 2nd argument is nonnegative. */
14700 return tree_expr_nonnegative_warnv_p (arg1,
14701 strict_overflow_p);
14703 CASE_FLT_FN (BUILT_IN_POWI):
14704 /* True if the 1st argument is nonnegative or the second
14705 argument is an even integer. */
14706 if (TREE_CODE (arg1) == INTEGER_CST
14707 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
14709 return tree_expr_nonnegative_warnv_p (arg0,
14710 strict_overflow_p);
14712 CASE_FLT_FN (BUILT_IN_POW):
14713 /* True if the 1st argument is nonnegative or the second
14714 argument is an even integer valued real. */
14715 if (TREE_CODE (arg1) == REAL_CST)
14720 c = TREE_REAL_CST (arg1);
14721 n = real_to_integer (&c);
14724 REAL_VALUE_TYPE cint;
14725 real_from_integer (&cint, VOIDmode, n,
14726 n < 0 ? -1 : 0, 0);
14727 if (real_identical (&c, &cint))
14731 return tree_expr_nonnegative_warnv_p (arg0,
14732 strict_overflow_p);
14737 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
14741 /* Return true if T is known to be non-negative. If the return
14742 value is based on the assumption that signed overflow is undefined,
14743 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14744 *STRICT_OVERFLOW_P. */
14747 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14749 enum tree_code code = TREE_CODE (t);
14750 if (TYPE_UNSIGNED (TREE_TYPE (t)))
14757 tree temp = TARGET_EXPR_SLOT (t);
14758 t = TARGET_EXPR_INITIAL (t);
14760 /* If the initializer is non-void, then it's a normal expression
14761 that will be assigned to the slot. */
14762 if (!VOID_TYPE_P (t))
14763 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
14765 /* Otherwise, the initializer sets the slot in some way. One common
14766 way is an assignment statement at the end of the initializer. */
14769 if (TREE_CODE (t) == BIND_EXPR)
14770 t = expr_last (BIND_EXPR_BODY (t));
14771 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
14772 || TREE_CODE (t) == TRY_CATCH_EXPR)
14773 t = expr_last (TREE_OPERAND (t, 0));
14774 else if (TREE_CODE (t) == STATEMENT_LIST)
14779 if (TREE_CODE (t) == MODIFY_EXPR
14780 && TREE_OPERAND (t, 0) == temp)
14781 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14782 strict_overflow_p);
14789 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
14790 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
14792 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
14793 get_callee_fndecl (t),
14796 strict_overflow_p);
14798 case COMPOUND_EXPR:
14800 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
14801 strict_overflow_p);
14803 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
14804 strict_overflow_p);
14806 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
14807 strict_overflow_p);
14810 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
14814 /* We don't know sign of `t', so be conservative and return false. */
14818 /* Return true if T is known to be non-negative. If the return
14819 value is based on the assumption that signed overflow is undefined,
14820 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14821 *STRICT_OVERFLOW_P. */
14824 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
14826 enum tree_code code;
14827 if (t == error_mark_node)
14830 code = TREE_CODE (t);
14831 switch (TREE_CODE_CLASS (code))
14834 case tcc_comparison:
14835 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14837 TREE_OPERAND (t, 0),
14838 TREE_OPERAND (t, 1),
14839 strict_overflow_p);
14842 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14844 TREE_OPERAND (t, 0),
14845 strict_overflow_p);
14848 case tcc_declaration:
14849 case tcc_reference:
14850 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14858 case TRUTH_AND_EXPR:
14859 case TRUTH_OR_EXPR:
14860 case TRUTH_XOR_EXPR:
14861 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
14863 TREE_OPERAND (t, 0),
14864 TREE_OPERAND (t, 1),
14865 strict_overflow_p);
14866 case TRUTH_NOT_EXPR:
14867 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
14869 TREE_OPERAND (t, 0),
14870 strict_overflow_p);
14877 case WITH_SIZE_EXPR:
14879 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
14882 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
14886 /* Return true if `t' is known to be non-negative. Handle warnings
14887 about undefined signed overflow. */
14890 tree_expr_nonnegative_p (tree t)
14892 bool ret, strict_overflow_p;
14894 strict_overflow_p = false;
14895 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
14896 if (strict_overflow_p)
14897 fold_overflow_warning (("assuming signed overflow does not occur when "
14898 "determining that expression is always "
14900 WARN_STRICT_OVERFLOW_MISC);
14905 /* Return true when (CODE OP0) is an address and is known to be nonzero.
14906 For floating point we further ensure that T is not denormal.
14907 Similar logic is present in nonzero_address in rtlanal.h.
14909 If the return value is based on the assumption that signed overflow
14910 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14911 change *STRICT_OVERFLOW_P. */
14914 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
14915 bool *strict_overflow_p)
14920 return tree_expr_nonzero_warnv_p (op0,
14921 strict_overflow_p);
14925 tree inner_type = TREE_TYPE (op0);
14926 tree outer_type = type;
14928 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
14929 && tree_expr_nonzero_warnv_p (op0,
14930 strict_overflow_p));
14934 case NON_LVALUE_EXPR:
14935 return tree_expr_nonzero_warnv_p (op0,
14936 strict_overflow_p);
14945 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
14946 For floating point we further ensure that T is not denormal.
14947 Similar logic is present in nonzero_address in rtlanal.h.
14949 If the return value is based on the assumption that signed overflow
14950 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
14951 change *STRICT_OVERFLOW_P. */
14954 tree_binary_nonzero_warnv_p (enum tree_code code,
14957 tree op1, bool *strict_overflow_p)
14959 bool sub_strict_overflow_p;
14962 case POINTER_PLUS_EXPR:
14964 if (TYPE_OVERFLOW_UNDEFINED (type))
14966 /* With the presence of negative values it is hard
14967 to say something. */
14968 sub_strict_overflow_p = false;
14969 if (!tree_expr_nonnegative_warnv_p (op0,
14970 &sub_strict_overflow_p)
14971 || !tree_expr_nonnegative_warnv_p (op1,
14972 &sub_strict_overflow_p))
14974 /* One of operands must be positive and the other non-negative. */
14975 /* We don't set *STRICT_OVERFLOW_P here: even if this value
14976 overflows, on a twos-complement machine the sum of two
14977 nonnegative numbers can never be zero. */
14978 return (tree_expr_nonzero_warnv_p (op0,
14980 || tree_expr_nonzero_warnv_p (op1,
14981 strict_overflow_p));
14986 if (TYPE_OVERFLOW_UNDEFINED (type))
14988 if (tree_expr_nonzero_warnv_p (op0,
14990 && tree_expr_nonzero_warnv_p (op1,
14991 strict_overflow_p))
14993 *strict_overflow_p = true;
15000 sub_strict_overflow_p = false;
15001 if (tree_expr_nonzero_warnv_p (op0,
15002 &sub_strict_overflow_p)
15003 && tree_expr_nonzero_warnv_p (op1,
15004 &sub_strict_overflow_p))
15006 if (sub_strict_overflow_p)
15007 *strict_overflow_p = true;
15012 sub_strict_overflow_p = false;
15013 if (tree_expr_nonzero_warnv_p (op0,
15014 &sub_strict_overflow_p))
15016 if (sub_strict_overflow_p)
15017 *strict_overflow_p = true;
15019 /* When both operands are nonzero, then MAX must be too. */
15020 if (tree_expr_nonzero_warnv_p (op1,
15021 strict_overflow_p))
15024 /* MAX where operand 0 is positive is positive. */
15025 return tree_expr_nonnegative_warnv_p (op0,
15026 strict_overflow_p);
15028 /* MAX where operand 1 is positive is positive. */
15029 else if (tree_expr_nonzero_warnv_p (op1,
15030 &sub_strict_overflow_p)
15031 && tree_expr_nonnegative_warnv_p (op1,
15032 &sub_strict_overflow_p))
15034 if (sub_strict_overflow_p)
15035 *strict_overflow_p = true;
15041 return (tree_expr_nonzero_warnv_p (op1,
15043 || tree_expr_nonzero_warnv_p (op0,
15044 strict_overflow_p));
15053 /* Return true when T is an address and is known to be nonzero.
15054 For floating point we further ensure that T is not denormal.
15055 Similar logic is present in nonzero_address in rtlanal.h.
15057 If the return value is based on the assumption that signed overflow
15058 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15059 change *STRICT_OVERFLOW_P. */
15062 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15064 bool sub_strict_overflow_p;
15065 switch (TREE_CODE (t))
15068 return !integer_zerop (t);
15072 tree base = TREE_OPERAND (t, 0);
15073 if (!DECL_P (base))
15074 base = get_base_address (base);
15079 /* Weak declarations may link to NULL. Other things may also be NULL
15080 so protect with -fdelete-null-pointer-checks; but not variables
15081 allocated on the stack. */
15083 && (flag_delete_null_pointer_checks
15084 || (DECL_CONTEXT (base)
15085 && TREE_CODE (DECL_CONTEXT (base)) == FUNCTION_DECL
15086 && auto_var_in_fn_p (base, DECL_CONTEXT (base)))))
15087 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15089 /* Constants are never weak. */
15090 if (CONSTANT_CLASS_P (base))
15097 sub_strict_overflow_p = false;
15098 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15099 &sub_strict_overflow_p)
15100 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15101 &sub_strict_overflow_p))
15103 if (sub_strict_overflow_p)
15104 *strict_overflow_p = true;
15115 /* Return true when T is an address and is known to be nonzero.
15116 For floating point we further ensure that T is not denormal.
15117 Similar logic is present in nonzero_address in rtlanal.h.
15119 If the return value is based on the assumption that signed overflow
15120 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15121 change *STRICT_OVERFLOW_P. */
15124 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15126 tree type = TREE_TYPE (t);
15127 enum tree_code code;
15129 /* Doing something useful for floating point would need more work. */
15130 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15133 code = TREE_CODE (t);
15134 switch (TREE_CODE_CLASS (code))
15137 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15138 strict_overflow_p);
15140 case tcc_comparison:
15141 return tree_binary_nonzero_warnv_p (code, type,
15142 TREE_OPERAND (t, 0),
15143 TREE_OPERAND (t, 1),
15144 strict_overflow_p);
15146 case tcc_declaration:
15147 case tcc_reference:
15148 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15156 case TRUTH_NOT_EXPR:
15157 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15158 strict_overflow_p);
15160 case TRUTH_AND_EXPR:
15161 case TRUTH_OR_EXPR:
15162 case TRUTH_XOR_EXPR:
15163 return tree_binary_nonzero_warnv_p (code, type,
15164 TREE_OPERAND (t, 0),
15165 TREE_OPERAND (t, 1),
15166 strict_overflow_p);
15173 case WITH_SIZE_EXPR:
15175 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15177 case COMPOUND_EXPR:
15180 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15181 strict_overflow_p);
15184 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15185 strict_overflow_p);
15188 return alloca_call_p (t);
15196 /* Return true when T is an address and is known to be nonzero.
15197 Handle warnings about undefined signed overflow. */
15200 tree_expr_nonzero_p (tree t)
15202 bool ret, strict_overflow_p;
15204 strict_overflow_p = false;
15205 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15206 if (strict_overflow_p)
15207 fold_overflow_warning (("assuming signed overflow does not occur when "
15208 "determining that expression is always "
15210 WARN_STRICT_OVERFLOW_MISC);
15214 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15215 attempt to fold the expression to a constant without modifying TYPE,
15218 If the expression could be simplified to a constant, then return
15219 the constant. If the expression would not be simplified to a
15220 constant, then return NULL_TREE. */
15223 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15225 tree tem = fold_binary (code, type, op0, op1);
15226 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15229 /* Given the components of a unary expression CODE, TYPE and OP0,
15230 attempt to fold the expression to a constant without modifying
15233 If the expression could be simplified to a constant, then return
15234 the constant. If the expression would not be simplified to a
15235 constant, then return NULL_TREE. */
15238 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15240 tree tem = fold_unary (code, type, op0);
15241 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15244 /* If EXP represents referencing an element in a constant string
15245 (either via pointer arithmetic or array indexing), return the
15246 tree representing the value accessed, otherwise return NULL. */
15249 fold_read_from_constant_string (tree exp)
15251 if ((TREE_CODE (exp) == INDIRECT_REF
15252 || TREE_CODE (exp) == ARRAY_REF)
15253 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15255 tree exp1 = TREE_OPERAND (exp, 0);
15258 location_t loc = EXPR_LOCATION (exp);
15260 if (TREE_CODE (exp) == INDIRECT_REF)
15261 string = string_constant (exp1, &index);
15264 tree low_bound = array_ref_low_bound (exp);
15265 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15267 /* Optimize the special-case of a zero lower bound.
15269 We convert the low_bound to sizetype to avoid some problems
15270 with constant folding. (E.g. suppose the lower bound is 1,
15271 and its mode is QI. Without the conversion,l (ARRAY
15272 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15273 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15274 if (! integer_zerop (low_bound))
15275 index = size_diffop_loc (loc, index,
15276 fold_convert_loc (loc, sizetype, low_bound));
15282 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15283 && TREE_CODE (string) == STRING_CST
15284 && TREE_CODE (index) == INTEGER_CST
15285 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15286 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15288 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15289 return build_int_cst_type (TREE_TYPE (exp),
15290 (TREE_STRING_POINTER (string)
15291 [TREE_INT_CST_LOW (index)]));
15296 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15297 an integer constant, real, or fixed-point constant.
15299 TYPE is the type of the result. */
15302 fold_negate_const (tree arg0, tree type)
15304 tree t = NULL_TREE;
15306 switch (TREE_CODE (arg0))
15310 double_int val = tree_to_double_int (arg0);
15311 int overflow = neg_double (val.low, val.high, &val.low, &val.high);
15313 t = force_fit_type_double (type, val, 1,
15314 (overflow | TREE_OVERFLOW (arg0))
15315 && !TYPE_UNSIGNED (type));
15320 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15325 FIXED_VALUE_TYPE f;
15326 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15327 &(TREE_FIXED_CST (arg0)), NULL,
15328 TYPE_SATURATING (type));
15329 t = build_fixed (type, f);
15330 /* Propagate overflow flags. */
15331 if (overflow_p | TREE_OVERFLOW (arg0))
15332 TREE_OVERFLOW (t) = 1;
15337 gcc_unreachable ();
15343 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15344 an integer constant or real constant.
15346 TYPE is the type of the result. */
15349 fold_abs_const (tree arg0, tree type)
15351 tree t = NULL_TREE;
15353 switch (TREE_CODE (arg0))
15357 double_int val = tree_to_double_int (arg0);
15359 /* If the value is unsigned or non-negative, then the absolute value
15360 is the same as the ordinary value. */
15361 if (TYPE_UNSIGNED (type)
15362 || !double_int_negative_p (val))
15365 /* If the value is negative, then the absolute value is
15371 overflow = neg_double (val.low, val.high, &val.low, &val.high);
15372 t = force_fit_type_double (type, val, -1,
15373 overflow | TREE_OVERFLOW (arg0));
15379 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15380 t = build_real (type, real_value_negate (&TREE_REAL_CST (arg0)));
15386 gcc_unreachable ();
15392 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15393 constant. TYPE is the type of the result. */
15396 fold_not_const (const_tree arg0, tree type)
15400 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15402 val = double_int_not (tree_to_double_int (arg0));
15403 return force_fit_type_double (type, val, 0, TREE_OVERFLOW (arg0));
15406 /* Given CODE, a relational operator, the target type, TYPE and two
15407 constant operands OP0 and OP1, return the result of the
15408 relational operation. If the result is not a compile time
15409 constant, then return NULL_TREE. */
15412 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15414 int result, invert;
15416 /* From here on, the only cases we handle are when the result is
15417 known to be a constant. */
15419 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15421 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15422 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15424 /* Handle the cases where either operand is a NaN. */
15425 if (real_isnan (c0) || real_isnan (c1))
15435 case UNORDERED_EXPR:
15449 if (flag_trapping_math)
15455 gcc_unreachable ();
15458 return constant_boolean_node (result, type);
15461 return constant_boolean_node (real_compare (code, c0, c1), type);
15464 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15466 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15467 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15468 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15471 /* Handle equality/inequality of complex constants. */
15472 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15474 tree rcond = fold_relational_const (code, type,
15475 TREE_REALPART (op0),
15476 TREE_REALPART (op1));
15477 tree icond = fold_relational_const (code, type,
15478 TREE_IMAGPART (op0),
15479 TREE_IMAGPART (op1));
15480 if (code == EQ_EXPR)
15481 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15482 else if (code == NE_EXPR)
15483 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15488 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15490 To compute GT, swap the arguments and do LT.
15491 To compute GE, do LT and invert the result.
15492 To compute LE, swap the arguments, do LT and invert the result.
15493 To compute NE, do EQ and invert the result.
15495 Therefore, the code below must handle only EQ and LT. */
15497 if (code == LE_EXPR || code == GT_EXPR)
15502 code = swap_tree_comparison (code);
15505 /* Note that it is safe to invert for real values here because we
15506 have already handled the one case that it matters. */
15509 if (code == NE_EXPR || code == GE_EXPR)
15512 code = invert_tree_comparison (code, false);
15515 /* Compute a result for LT or EQ if args permit;
15516 Otherwise return T. */
15517 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15519 if (code == EQ_EXPR)
15520 result = tree_int_cst_equal (op0, op1);
15521 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15522 result = INT_CST_LT_UNSIGNED (op0, op1);
15524 result = INT_CST_LT (op0, op1);
15531 return constant_boolean_node (result, type);
15534 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15535 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15539 fold_build_cleanup_point_expr (tree type, tree expr)
15541 /* If the expression does not have side effects then we don't have to wrap
15542 it with a cleanup point expression. */
15543 if (!TREE_SIDE_EFFECTS (expr))
15546 /* If the expression is a return, check to see if the expression inside the
15547 return has no side effects or the right hand side of the modify expression
15548 inside the return. If either don't have side effects set we don't need to
15549 wrap the expression in a cleanup point expression. Note we don't check the
15550 left hand side of the modify because it should always be a return decl. */
15551 if (TREE_CODE (expr) == RETURN_EXPR)
15553 tree op = TREE_OPERAND (expr, 0);
15554 if (!op || !TREE_SIDE_EFFECTS (op))
15556 op = TREE_OPERAND (op, 1);
15557 if (!TREE_SIDE_EFFECTS (op))
15561 return build1 (CLEANUP_POINT_EXPR, type, expr);
15564 /* Given a pointer value OP0 and a type TYPE, return a simplified version
15565 of an indirection through OP0, or NULL_TREE if no simplification is
15569 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
15575 subtype = TREE_TYPE (sub);
15576 if (!POINTER_TYPE_P (subtype))
15579 if (TREE_CODE (sub) == ADDR_EXPR)
15581 tree op = TREE_OPERAND (sub, 0);
15582 tree optype = TREE_TYPE (op);
15583 /* *&CONST_DECL -> to the value of the const decl. */
15584 if (TREE_CODE (op) == CONST_DECL)
15585 return DECL_INITIAL (op);
15586 /* *&p => p; make sure to handle *&"str"[cst] here. */
15587 if (type == optype)
15589 tree fop = fold_read_from_constant_string (op);
15595 /* *(foo *)&fooarray => fooarray[0] */
15596 else if (TREE_CODE (optype) == ARRAY_TYPE
15597 && type == TREE_TYPE (optype))
15599 tree type_domain = TYPE_DOMAIN (optype);
15600 tree min_val = size_zero_node;
15601 if (type_domain && TYPE_MIN_VALUE (type_domain))
15602 min_val = TYPE_MIN_VALUE (type_domain);
15603 op0 = build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
15604 SET_EXPR_LOCATION (op0, loc);
15607 /* *(foo *)&complexfoo => __real__ complexfoo */
15608 else if (TREE_CODE (optype) == COMPLEX_TYPE
15609 && type == TREE_TYPE (optype))
15610 return fold_build1_loc (loc, REALPART_EXPR, type, op);
15611 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
15612 else if (TREE_CODE (optype) == VECTOR_TYPE
15613 && type == TREE_TYPE (optype))
15615 tree part_width = TYPE_SIZE (type);
15616 tree index = bitsize_int (0);
15617 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
15621 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
15622 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15623 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15625 tree op00 = TREE_OPERAND (sub, 0);
15626 tree op01 = TREE_OPERAND (sub, 1);
15630 op00type = TREE_TYPE (op00);
15631 if (TREE_CODE (op00) == ADDR_EXPR
15632 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
15633 && type == TREE_TYPE (TREE_TYPE (op00type)))
15635 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
15636 tree part_width = TYPE_SIZE (type);
15637 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
15638 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
15639 tree index = bitsize_int (indexi);
15641 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
15642 return fold_build3_loc (loc,
15643 BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
15644 part_width, index);
15650 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
15651 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
15652 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
15654 tree op00 = TREE_OPERAND (sub, 0);
15655 tree op01 = TREE_OPERAND (sub, 1);
15659 op00type = TREE_TYPE (op00);
15660 if (TREE_CODE (op00) == ADDR_EXPR
15661 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
15662 && type == TREE_TYPE (TREE_TYPE (op00type)))
15664 tree size = TYPE_SIZE_UNIT (type);
15665 if (tree_int_cst_equal (size, op01))
15666 return fold_build1_loc (loc, IMAGPART_EXPR, type,
15667 TREE_OPERAND (op00, 0));
15671 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
15672 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
15673 && type == TREE_TYPE (TREE_TYPE (subtype)))
15676 tree min_val = size_zero_node;
15677 sub = build_fold_indirect_ref_loc (loc, sub);
15678 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
15679 if (type_domain && TYPE_MIN_VALUE (type_domain))
15680 min_val = TYPE_MIN_VALUE (type_domain);
15681 op0 = build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
15682 SET_EXPR_LOCATION (op0, loc);
15689 /* Builds an expression for an indirection through T, simplifying some
15693 build_fold_indirect_ref_loc (location_t loc, tree t)
15695 tree type = TREE_TYPE (TREE_TYPE (t));
15696 tree sub = fold_indirect_ref_1 (loc, type, t);
15701 t = build1 (INDIRECT_REF, type, t);
15702 SET_EXPR_LOCATION (t, loc);
15706 /* Given an INDIRECT_REF T, return either T or a simplified version. */
15709 fold_indirect_ref_loc (location_t loc, tree t)
15711 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
15719 /* Strip non-trapping, non-side-effecting tree nodes from an expression
15720 whose result is ignored. The type of the returned tree need not be
15721 the same as the original expression. */
15724 fold_ignored_result (tree t)
15726 if (!TREE_SIDE_EFFECTS (t))
15727 return integer_zero_node;
15730 switch (TREE_CODE_CLASS (TREE_CODE (t)))
15733 t = TREE_OPERAND (t, 0);
15737 case tcc_comparison:
15738 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15739 t = TREE_OPERAND (t, 0);
15740 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
15741 t = TREE_OPERAND (t, 1);
15746 case tcc_expression:
15747 switch (TREE_CODE (t))
15749 case COMPOUND_EXPR:
15750 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
15752 t = TREE_OPERAND (t, 0);
15756 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
15757 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
15759 t = TREE_OPERAND (t, 0);
15772 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
15773 This can only be applied to objects of a sizetype. */
15776 round_up_loc (location_t loc, tree value, int divisor)
15778 tree div = NULL_TREE;
15780 gcc_assert (divisor > 0);
15784 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15785 have to do anything. Only do this when we are not given a const,
15786 because in that case, this check is more expensive than just
15788 if (TREE_CODE (value) != INTEGER_CST)
15790 div = build_int_cst (TREE_TYPE (value), divisor);
15792 if (multiple_of_p (TREE_TYPE (value), value, div))
15796 /* If divisor is a power of two, simplify this to bit manipulation. */
15797 if (divisor == (divisor & -divisor))
15799 if (TREE_CODE (value) == INTEGER_CST)
15801 double_int val = tree_to_double_int (value);
15804 if ((val.low & (divisor - 1)) == 0)
15807 overflow_p = TREE_OVERFLOW (value);
15808 val.low &= ~(divisor - 1);
15809 val.low += divisor;
15817 return force_fit_type_double (TREE_TYPE (value), val,
15824 t = build_int_cst (TREE_TYPE (value), divisor - 1);
15825 value = size_binop_loc (loc, PLUS_EXPR, value, t);
15826 t = build_int_cst (TREE_TYPE (value), -divisor);
15827 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15833 div = build_int_cst (TREE_TYPE (value), divisor);
15834 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
15835 value = size_binop_loc (loc, MULT_EXPR, value, div);
15841 /* Likewise, but round down. */
15844 round_down_loc (location_t loc, tree value, int divisor)
15846 tree div = NULL_TREE;
15848 gcc_assert (divisor > 0);
15852 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
15853 have to do anything. Only do this when we are not given a const,
15854 because in that case, this check is more expensive than just
15856 if (TREE_CODE (value) != INTEGER_CST)
15858 div = build_int_cst (TREE_TYPE (value), divisor);
15860 if (multiple_of_p (TREE_TYPE (value), value, div))
15864 /* If divisor is a power of two, simplify this to bit manipulation. */
15865 if (divisor == (divisor & -divisor))
15869 t = build_int_cst (TREE_TYPE (value), -divisor);
15870 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
15875 div = build_int_cst (TREE_TYPE (value), divisor);
15876 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
15877 value = size_binop_loc (loc, MULT_EXPR, value, div);
15883 /* Returns the pointer to the base of the object addressed by EXP and
15884 extracts the information about the offset of the access, storing it
15885 to PBITPOS and POFFSET. */
15888 split_address_to_core_and_offset (tree exp,
15889 HOST_WIDE_INT *pbitpos, tree *poffset)
15892 enum machine_mode mode;
15893 int unsignedp, volatilep;
15894 HOST_WIDE_INT bitsize;
15895 location_t loc = EXPR_LOCATION (exp);
15897 if (TREE_CODE (exp) == ADDR_EXPR)
15899 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
15900 poffset, &mode, &unsignedp, &volatilep,
15902 core = build_fold_addr_expr_loc (loc, core);
15908 *poffset = NULL_TREE;
15914 /* Returns true if addresses of E1 and E2 differ by a constant, false
15915 otherwise. If they do, E1 - E2 is stored in *DIFF. */
15918 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
15921 HOST_WIDE_INT bitpos1, bitpos2;
15922 tree toffset1, toffset2, tdiff, type;
15924 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
15925 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
15927 if (bitpos1 % BITS_PER_UNIT != 0
15928 || bitpos2 % BITS_PER_UNIT != 0
15929 || !operand_equal_p (core1, core2, 0))
15932 if (toffset1 && toffset2)
15934 type = TREE_TYPE (toffset1);
15935 if (type != TREE_TYPE (toffset2))
15936 toffset2 = fold_convert (type, toffset2);
15938 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
15939 if (!cst_and_fits_in_hwi (tdiff))
15942 *diff = int_cst_value (tdiff);
15944 else if (toffset1 || toffset2)
15946 /* If only one of the offsets is non-constant, the difference cannot
15953 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
15957 /* Simplify the floating point expression EXP when the sign of the
15958 result is not significant. Return NULL_TREE if no simplification
15962 fold_strip_sign_ops (tree exp)
15965 location_t loc = EXPR_LOCATION (exp);
15967 switch (TREE_CODE (exp))
15971 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15972 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
15976 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
15978 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
15979 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15980 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
15981 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
15982 arg0 ? arg0 : TREE_OPERAND (exp, 0),
15983 arg1 ? arg1 : TREE_OPERAND (exp, 1));
15986 case COMPOUND_EXPR:
15987 arg0 = TREE_OPERAND (exp, 0);
15988 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15990 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
15994 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
15995 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
15997 return fold_build3_loc (loc,
15998 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
15999 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16000 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16005 const enum built_in_function fcode = builtin_mathfn_code (exp);
16008 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16009 /* Strip copysign function call, return the 1st argument. */
16010 arg0 = CALL_EXPR_ARG (exp, 0);
16011 arg1 = CALL_EXPR_ARG (exp, 1);
16012 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16015 /* Strip sign ops from the argument of "odd" math functions. */
16016 if (negate_mathfn_p (fcode))
16018 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16020 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);