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
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, size_binop
31 and force_fit_type_double.
33 fold takes a tree as argument and returns a simplified tree.
35 size_binop takes a tree code for an arithmetic operation
36 and two operands that are trees, and produces a tree for the
37 result, assuming the type comes from `sizetype'.
39 size_int takes an integer value, and creates a tree constant
40 with type from `sizetype'.
42 force_fit_type_double takes a constant, an overflowable flag and a
43 prior overflow indicator. It forces the value to fit the type and
46 Note: Since the folders get called on non-gimple code as well as
47 gimple code, we need to handle GIMPLE tuples as well as their
48 corresponding tree equivalents. */
52 #include "coretypes.h"
57 #include "fixed-value.h"
66 #include "langhooks.h"
70 /* Nonzero if we are folding constants inside an initializer; zero
72 int folding_initializer = 0;
74 /* The following constants represent a bit based encoding of GCC's
75 comparison operators. This encoding simplifies transformations
76 on relational comparison operators, such as AND and OR. */
77 enum comparison_code {
96 static void encode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT, HOST_WIDE_INT);
97 static void decode (HOST_WIDE_INT *, unsigned HOST_WIDE_INT *, HOST_WIDE_INT *);
98 static bool negate_mathfn_p (enum built_in_function);
99 static bool negate_expr_p (tree);
100 static tree negate_expr (tree);
101 static tree split_tree (tree, enum tree_code, tree *, tree *, tree *, int);
102 static tree associate_trees (location_t, tree, tree, enum tree_code, tree);
103 static tree const_binop (enum tree_code, tree, tree, int);
104 static enum comparison_code comparison_to_compcode (enum tree_code);
105 static enum tree_code compcode_to_comparison (enum comparison_code);
106 static int operand_equal_for_comparison_p (tree, tree, tree);
107 static int twoval_comparison_p (tree, tree *, tree *, int *);
108 static tree eval_subst (location_t, tree, tree, tree, tree, tree);
109 static tree pedantic_omit_one_operand_loc (location_t, tree, tree, tree);
110 static tree distribute_bit_expr (location_t, enum tree_code, tree, tree, tree);
111 static tree make_bit_field_ref (location_t, tree, tree,
112 HOST_WIDE_INT, HOST_WIDE_INT, int);
113 static tree optimize_bit_field_compare (location_t, enum tree_code,
115 static tree decode_field_reference (location_t, tree, HOST_WIDE_INT *,
117 enum machine_mode *, int *, int *,
119 static int all_ones_mask_p (const_tree, int);
120 static tree sign_bit_p (tree, const_tree);
121 static int simple_operand_p (const_tree);
122 static tree range_binop (enum tree_code, tree, tree, int, tree, int);
123 static tree range_predecessor (tree);
124 static tree range_successor (tree);
125 extern tree make_range (tree, int *, tree *, tree *, bool *);
126 extern bool merge_ranges (int *, tree *, tree *, int, tree, tree, int,
128 static tree fold_range_test (location_t, enum tree_code, tree, tree, tree);
129 static tree fold_cond_expr_with_comparison (location_t, tree, tree, tree, tree);
130 static tree unextend (tree, int, int, tree);
131 static tree fold_truthop (location_t, enum tree_code, tree, tree, tree);
132 static tree optimize_minmax_comparison (location_t, enum tree_code,
134 static tree extract_muldiv (tree, tree, enum tree_code, tree, bool *);
135 static tree extract_muldiv_1 (tree, tree, enum tree_code, tree, bool *);
136 static tree fold_binary_op_with_conditional_arg (location_t,
137 enum tree_code, tree,
140 static tree fold_mathfn_compare (location_t,
141 enum built_in_function, enum tree_code,
143 static tree fold_inf_compare (location_t, enum tree_code, tree, tree, tree);
144 static tree fold_div_compare (location_t, enum tree_code, tree, tree, tree);
145 static bool reorder_operands_p (const_tree, const_tree);
146 static tree fold_negate_const (tree, tree);
147 static tree fold_not_const (tree, tree);
148 static tree fold_relational_const (enum tree_code, tree, tree, tree);
149 static tree fold_convert_const (enum tree_code, tree, tree);
152 /* We know that A1 + B1 = SUM1, using 2's complement arithmetic and ignoring
153 overflow. Suppose A, B and SUM have the same respective signs as A1, B1,
154 and SUM1. Then this yields nonzero if overflow occurred during the
157 Overflow occurs if A and B have the same sign, but A and SUM differ in
158 sign. Use `^' to test whether signs differ, and `< 0' to isolate the
160 #define OVERFLOW_SUM_SIGN(a, b, sum) ((~((a) ^ (b)) & ((a) ^ (sum))) < 0)
162 /* To do constant folding on INTEGER_CST nodes requires two-word arithmetic.
163 We do that by representing the two-word integer in 4 words, with only
164 HOST_BITS_PER_WIDE_INT / 2 bits stored in each word, as a positive
165 number. The value of the word is LOWPART + HIGHPART * BASE. */
168 ((x) & (((unsigned HOST_WIDE_INT) 1 << (HOST_BITS_PER_WIDE_INT / 2)) - 1))
169 #define HIGHPART(x) \
170 ((unsigned HOST_WIDE_INT) (x) >> HOST_BITS_PER_WIDE_INT / 2)
171 #define BASE ((unsigned HOST_WIDE_INT) 1 << HOST_BITS_PER_WIDE_INT / 2)
173 /* Unpack a two-word integer into 4 words.
174 LOW and HI are the integer, as two `HOST_WIDE_INT' pieces.
175 WORDS points to the array of HOST_WIDE_INTs. */
178 encode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
180 words[0] = LOWPART (low);
181 words[1] = HIGHPART (low);
182 words[2] = LOWPART (hi);
183 words[3] = HIGHPART (hi);
186 /* Pack an array of 4 words into a two-word integer.
187 WORDS points to the array of words.
188 The integer is stored into *LOW and *HI as two `HOST_WIDE_INT' pieces. */
191 decode (HOST_WIDE_INT *words, unsigned HOST_WIDE_INT *low,
194 *low = words[0] + words[1] * BASE;
195 *hi = words[2] + words[3] * BASE;
198 /* Force the double-word integer L1, H1 to be within the range of the
199 integer type TYPE. Stores the properly truncated and sign-extended
200 double-word integer in *LV, *HV. Returns true if the operation
201 overflows, that is, argument and result are different. */
204 fit_double_type (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
205 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, const_tree type)
207 unsigned HOST_WIDE_INT low0 = l1;
208 HOST_WIDE_INT high0 = h1;
209 unsigned int prec = int_or_pointer_precision (type);
210 int sign_extended_type;
212 /* Size types *are* sign extended. */
213 sign_extended_type = (!TYPE_UNSIGNED (type)
214 || (TREE_CODE (type) == INTEGER_TYPE
215 && TYPE_IS_SIZETYPE (type)));
217 /* First clear all bits that are beyond the type's precision. */
218 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
220 else if (prec > HOST_BITS_PER_WIDE_INT)
221 h1 &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
225 if (prec < HOST_BITS_PER_WIDE_INT)
226 l1 &= ~((HOST_WIDE_INT) (-1) << prec);
229 /* Then do sign extension if necessary. */
230 if (!sign_extended_type)
231 /* No sign extension */;
232 else if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
233 /* Correct width already. */;
234 else if (prec > HOST_BITS_PER_WIDE_INT)
236 /* Sign extend top half? */
237 if (h1 & ((unsigned HOST_WIDE_INT)1
238 << (prec - HOST_BITS_PER_WIDE_INT - 1)))
239 h1 |= (HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT);
241 else if (prec == HOST_BITS_PER_WIDE_INT)
243 if ((HOST_WIDE_INT)l1 < 0)
248 /* Sign extend bottom half? */
249 if (l1 & ((unsigned HOST_WIDE_INT)1 << (prec - 1)))
252 l1 |= (HOST_WIDE_INT)(-1) << prec;
259 /* If the value didn't fit, signal overflow. */
260 return l1 != low0 || h1 != high0;
263 /* We force the double-int HIGH:LOW to the range of the type TYPE by
264 sign or zero extending it.
265 OVERFLOWABLE indicates if we are interested
266 in overflow of the value, when >0 we are only interested in signed
267 overflow, for <0 we are interested in any overflow. OVERFLOWED
268 indicates whether overflow has already occurred. CONST_OVERFLOWED
269 indicates whether constant overflow has already occurred. We force
270 T's value to be within range of T's type (by setting to 0 or 1 all
271 the bits outside the type's range). We set TREE_OVERFLOWED if,
272 OVERFLOWED is nonzero,
273 or OVERFLOWABLE is >0 and signed overflow occurs
274 or OVERFLOWABLE is <0 and any overflow occurs
275 We return a new tree node for the extended double-int. The node
276 is shared if no overflow flags are set. */
279 force_fit_type_double (tree type, unsigned HOST_WIDE_INT low,
280 HOST_WIDE_INT high, int overflowable,
283 int sign_extended_type;
286 /* Size types *are* sign extended. */
287 sign_extended_type = (!TYPE_UNSIGNED (type)
288 || (TREE_CODE (type) == INTEGER_TYPE
289 && TYPE_IS_SIZETYPE (type)));
291 overflow = fit_double_type (low, high, &low, &high, type);
293 /* If we need to set overflow flags, return a new unshared node. */
294 if (overflowed || overflow)
298 || (overflowable > 0 && sign_extended_type))
300 tree t = make_node (INTEGER_CST);
301 TREE_INT_CST_LOW (t) = low;
302 TREE_INT_CST_HIGH (t) = high;
303 TREE_TYPE (t) = type;
304 TREE_OVERFLOW (t) = 1;
309 /* Else build a shared node. */
310 return build_int_cst_wide (type, low, high);
313 /* Add two doubleword integers with doubleword result.
314 Return nonzero if the operation overflows according to UNSIGNED_P.
315 Each argument is given as two `HOST_WIDE_INT' pieces.
316 One argument is L1 and H1; the other, L2 and H2.
317 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
320 add_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
321 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
322 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
325 unsigned HOST_WIDE_INT l;
329 h = h1 + h2 + (l < l1);
335 return (unsigned HOST_WIDE_INT) h < (unsigned HOST_WIDE_INT) h1;
337 return OVERFLOW_SUM_SIGN (h1, h2, h);
340 /* Negate a doubleword integer with doubleword result.
341 Return nonzero if the operation overflows, assuming it's signed.
342 The argument is given as two `HOST_WIDE_INT' pieces in L1 and H1.
343 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
346 neg_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
347 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
353 return (*hv & h1) < 0;
363 /* Multiply two doubleword integers with doubleword result.
364 Return nonzero if the operation overflows according to UNSIGNED_P.
365 Each argument is given as two `HOST_WIDE_INT' pieces.
366 One argument is L1 and H1; the other, L2 and H2.
367 The value is stored as two `HOST_WIDE_INT' pieces in *LV and *HV. */
370 mul_double_with_sign (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
371 unsigned HOST_WIDE_INT l2, HOST_WIDE_INT h2,
372 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
375 HOST_WIDE_INT arg1[4];
376 HOST_WIDE_INT arg2[4];
377 HOST_WIDE_INT prod[4 * 2];
378 unsigned HOST_WIDE_INT carry;
380 unsigned HOST_WIDE_INT toplow, neglow;
381 HOST_WIDE_INT tophigh, neghigh;
383 encode (arg1, l1, h1);
384 encode (arg2, l2, h2);
386 memset (prod, 0, sizeof prod);
388 for (i = 0; i < 4; i++)
391 for (j = 0; j < 4; j++)
394 /* This product is <= 0xFFFE0001, the sum <= 0xFFFF0000. */
395 carry += arg1[i] * arg2[j];
396 /* Since prod[p] < 0xFFFF, this sum <= 0xFFFFFFFF. */
398 prod[k] = LOWPART (carry);
399 carry = HIGHPART (carry);
404 decode (prod, lv, hv);
405 decode (prod + 4, &toplow, &tophigh);
407 /* Unsigned overflow is immediate. */
409 return (toplow | tophigh) != 0;
411 /* Check for signed overflow by calculating the signed representation of the
412 top half of the result; it should agree with the low half's sign bit. */
415 neg_double (l2, h2, &neglow, &neghigh);
416 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
420 neg_double (l1, h1, &neglow, &neghigh);
421 add_double (neglow, neghigh, toplow, tophigh, &toplow, &tophigh);
423 return (*hv < 0 ? ~(toplow & tophigh) : toplow | tophigh) != 0;
426 /* Shift the doubleword integer in L1, H1 left by COUNT places
427 keeping only PREC bits of result.
428 Shift right if COUNT is negative.
429 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
430 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
433 lshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
434 HOST_WIDE_INT count, unsigned int prec,
435 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv, int arith)
437 unsigned HOST_WIDE_INT signmask;
441 rshift_double (l1, h1, -count, prec, lv, hv, arith);
445 if (SHIFT_COUNT_TRUNCATED)
448 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
450 /* Shifting by the host word size is undefined according to the
451 ANSI standard, so we must handle this as a special case. */
455 else if (count >= HOST_BITS_PER_WIDE_INT)
457 *hv = l1 << (count - HOST_BITS_PER_WIDE_INT);
462 *hv = (((unsigned HOST_WIDE_INT) h1 << count)
463 | (l1 >> (HOST_BITS_PER_WIDE_INT - count - 1) >> 1));
467 /* Sign extend all bits that are beyond the precision. */
469 signmask = -((prec > HOST_BITS_PER_WIDE_INT
470 ? ((unsigned HOST_WIDE_INT) *hv
471 >> (prec - HOST_BITS_PER_WIDE_INT - 1))
472 : (*lv >> (prec - 1))) & 1);
474 if (prec >= 2 * HOST_BITS_PER_WIDE_INT)
476 else if (prec >= HOST_BITS_PER_WIDE_INT)
478 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
479 *hv |= signmask << (prec - HOST_BITS_PER_WIDE_INT);
484 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << prec);
485 *lv |= signmask << prec;
489 /* Shift the doubleword integer in L1, H1 right by COUNT places
490 keeping only PREC bits of result. COUNT must be positive.
491 ARITH nonzero specifies arithmetic shifting; otherwise use logical shift.
492 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
495 rshift_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
496 HOST_WIDE_INT count, unsigned int prec,
497 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv,
500 unsigned HOST_WIDE_INT signmask;
503 ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
506 if (SHIFT_COUNT_TRUNCATED)
509 if (count >= 2 * HOST_BITS_PER_WIDE_INT)
511 /* Shifting by the host word size is undefined according to the
512 ANSI standard, so we must handle this as a special case. */
516 else if (count >= HOST_BITS_PER_WIDE_INT)
519 *lv = (unsigned HOST_WIDE_INT) h1 >> (count - HOST_BITS_PER_WIDE_INT);
523 *hv = (unsigned HOST_WIDE_INT) h1 >> count;
525 | ((unsigned HOST_WIDE_INT) h1 << (HOST_BITS_PER_WIDE_INT - count - 1) << 1));
528 /* Zero / sign extend all bits that are beyond the precision. */
530 if (count >= (HOST_WIDE_INT)prec)
535 else if ((prec - count) >= 2 * HOST_BITS_PER_WIDE_INT)
537 else if ((prec - count) >= HOST_BITS_PER_WIDE_INT)
539 *hv &= ~((HOST_WIDE_INT) (-1) << (prec - count - HOST_BITS_PER_WIDE_INT));
540 *hv |= signmask << (prec - count - HOST_BITS_PER_WIDE_INT);
545 *lv &= ~((unsigned HOST_WIDE_INT) (-1) << (prec - count));
546 *lv |= signmask << (prec - count);
550 /* Rotate the doubleword integer in L1, H1 left by COUNT places
551 keeping only PREC bits of result.
552 Rotate right if COUNT is negative.
553 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
556 lrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
557 HOST_WIDE_INT count, unsigned int prec,
558 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
560 unsigned HOST_WIDE_INT s1l, s2l;
561 HOST_WIDE_INT s1h, s2h;
567 lshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
568 rshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
573 /* Rotate the doubleword integer in L1, H1 left by COUNT places
574 keeping only PREC bits of result. COUNT must be positive.
575 Store the value as two `HOST_WIDE_INT' pieces in *LV and *HV. */
578 rrotate_double (unsigned HOST_WIDE_INT l1, HOST_WIDE_INT h1,
579 HOST_WIDE_INT count, unsigned int prec,
580 unsigned HOST_WIDE_INT *lv, HOST_WIDE_INT *hv)
582 unsigned HOST_WIDE_INT s1l, s2l;
583 HOST_WIDE_INT s1h, s2h;
589 rshift_double (l1, h1, count, prec, &s1l, &s1h, 0);
590 lshift_double (l1, h1, prec - count, prec, &s2l, &s2h, 0);
595 /* Divide doubleword integer LNUM, HNUM by doubleword integer LDEN, HDEN
596 for a quotient (stored in *LQUO, *HQUO) and remainder (in *LREM, *HREM).
597 CODE is a tree code for a kind of division, one of
598 TRUNC_DIV_EXPR, FLOOR_DIV_EXPR, CEIL_DIV_EXPR, ROUND_DIV_EXPR
600 It controls how the quotient is rounded to an integer.
601 Return nonzero if the operation overflows.
602 UNS nonzero says do unsigned division. */
605 div_and_round_double (enum tree_code code, int uns,
606 unsigned HOST_WIDE_INT lnum_orig, /* num == numerator == dividend */
607 HOST_WIDE_INT hnum_orig,
608 unsigned HOST_WIDE_INT lden_orig, /* den == denominator == divisor */
609 HOST_WIDE_INT hden_orig,
610 unsigned HOST_WIDE_INT *lquo,
611 HOST_WIDE_INT *hquo, unsigned HOST_WIDE_INT *lrem,
615 HOST_WIDE_INT num[4 + 1]; /* extra element for scaling. */
616 HOST_WIDE_INT den[4], quo[4];
618 unsigned HOST_WIDE_INT work;
619 unsigned HOST_WIDE_INT carry = 0;
620 unsigned HOST_WIDE_INT lnum = lnum_orig;
621 HOST_WIDE_INT hnum = hnum_orig;
622 unsigned HOST_WIDE_INT lden = lden_orig;
623 HOST_WIDE_INT hden = hden_orig;
626 if (hden == 0 && lden == 0)
627 overflow = 1, lden = 1;
629 /* Calculate quotient sign and convert operands to unsigned. */
635 /* (minimum integer) / (-1) is the only overflow case. */
636 if (neg_double (lnum, hnum, &lnum, &hnum)
637 && ((HOST_WIDE_INT) lden & hden) == -1)
643 neg_double (lden, hden, &lden, &hden);
647 if (hnum == 0 && hden == 0)
648 { /* single precision */
650 /* This unsigned division rounds toward zero. */
656 { /* trivial case: dividend < divisor */
657 /* hden != 0 already checked. */
664 memset (quo, 0, sizeof quo);
666 memset (num, 0, sizeof num); /* to zero 9th element */
667 memset (den, 0, sizeof den);
669 encode (num, lnum, hnum);
670 encode (den, lden, hden);
672 /* Special code for when the divisor < BASE. */
673 if (hden == 0 && lden < (unsigned HOST_WIDE_INT) BASE)
675 /* hnum != 0 already checked. */
676 for (i = 4 - 1; i >= 0; i--)
678 work = num[i] + carry * BASE;
679 quo[i] = work / lden;
685 /* Full double precision division,
686 with thanks to Don Knuth's "Seminumerical Algorithms". */
687 int num_hi_sig, den_hi_sig;
688 unsigned HOST_WIDE_INT quo_est, scale;
690 /* Find the highest nonzero divisor digit. */
691 for (i = 4 - 1;; i--)
698 /* Insure that the first digit of the divisor is at least BASE/2.
699 This is required by the quotient digit estimation algorithm. */
701 scale = BASE / (den[den_hi_sig] + 1);
703 { /* scale divisor and dividend */
705 for (i = 0; i <= 4 - 1; i++)
707 work = (num[i] * scale) + carry;
708 num[i] = LOWPART (work);
709 carry = HIGHPART (work);
714 for (i = 0; i <= 4 - 1; i++)
716 work = (den[i] * scale) + carry;
717 den[i] = LOWPART (work);
718 carry = HIGHPART (work);
719 if (den[i] != 0) den_hi_sig = i;
726 for (i = num_hi_sig - den_hi_sig - 1; i >= 0; i--)
728 /* Guess the next quotient digit, quo_est, by dividing the first
729 two remaining dividend digits by the high order quotient digit.
730 quo_est is never low and is at most 2 high. */
731 unsigned HOST_WIDE_INT tmp;
733 num_hi_sig = i + den_hi_sig + 1;
734 work = num[num_hi_sig] * BASE + num[num_hi_sig - 1];
735 if (num[num_hi_sig] != den[den_hi_sig])
736 quo_est = work / den[den_hi_sig];
740 /* Refine quo_est so it's usually correct, and at most one high. */
741 tmp = work - quo_est * den[den_hi_sig];
743 && (den[den_hi_sig - 1] * quo_est
744 > (tmp * BASE + num[num_hi_sig - 2])))
747 /* Try QUO_EST as the quotient digit, by multiplying the
748 divisor by QUO_EST and subtracting from the remaining dividend.
749 Keep in mind that QUO_EST is the I - 1st digit. */
752 for (j = 0; j <= den_hi_sig; j++)
754 work = quo_est * den[j] + carry;
755 carry = HIGHPART (work);
756 work = num[i + j] - LOWPART (work);
757 num[i + j] = LOWPART (work);
758 carry += HIGHPART (work) != 0;
761 /* If quo_est was high by one, then num[i] went negative and
762 we need to correct things. */
763 if (num[num_hi_sig] < (HOST_WIDE_INT) carry)
766 carry = 0; /* add divisor back in */
767 for (j = 0; j <= den_hi_sig; j++)
769 work = num[i + j] + den[j] + carry;
770 carry = HIGHPART (work);
771 num[i + j] = LOWPART (work);
774 num [num_hi_sig] += carry;
777 /* Store the quotient digit. */
782 decode (quo, lquo, hquo);
785 /* If result is negative, make it so. */
787 neg_double (*lquo, *hquo, lquo, hquo);
789 /* Compute trial remainder: rem = num - (quo * den) */
790 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
791 neg_double (*lrem, *hrem, lrem, hrem);
792 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
797 case TRUNC_MOD_EXPR: /* round toward zero */
798 case EXACT_DIV_EXPR: /* for this one, it shouldn't matter */
802 case FLOOR_MOD_EXPR: /* round toward negative infinity */
803 if (quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio < 0 && rem != 0 */
806 add_double (*lquo, *hquo, (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1,
814 case CEIL_MOD_EXPR: /* round toward positive infinity */
815 if (!quo_neg && (*lrem != 0 || *hrem != 0)) /* ratio > 0 && rem != 0 */
817 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
825 case ROUND_MOD_EXPR: /* round to closest integer */
827 unsigned HOST_WIDE_INT labs_rem = *lrem;
828 HOST_WIDE_INT habs_rem = *hrem;
829 unsigned HOST_WIDE_INT labs_den = lden, ltwice;
830 HOST_WIDE_INT habs_den = hden, htwice;
832 /* Get absolute values. */
834 neg_double (*lrem, *hrem, &labs_rem, &habs_rem);
836 neg_double (lden, hden, &labs_den, &habs_den);
838 /* If (2 * abs (lrem) >= abs (lden)), adjust the quotient. */
839 mul_double ((HOST_WIDE_INT) 2, (HOST_WIDE_INT) 0,
840 labs_rem, habs_rem, <wice, &htwice);
842 if (((unsigned HOST_WIDE_INT) habs_den
843 < (unsigned HOST_WIDE_INT) htwice)
844 || (((unsigned HOST_WIDE_INT) habs_den
845 == (unsigned HOST_WIDE_INT) htwice)
846 && (labs_den <= ltwice)))
850 add_double (*lquo, *hquo,
851 (HOST_WIDE_INT) -1, (HOST_WIDE_INT) -1, lquo, hquo);
854 add_double (*lquo, *hquo, (HOST_WIDE_INT) 1, (HOST_WIDE_INT) 0,
866 /* Compute true remainder: rem = num - (quo * den) */
867 mul_double (*lquo, *hquo, lden_orig, hden_orig, lrem, hrem);
868 neg_double (*lrem, *hrem, lrem, hrem);
869 add_double (lnum_orig, hnum_orig, *lrem, *hrem, lrem, hrem);
873 /* If ARG2 divides ARG1 with zero remainder, carries out the division
874 of type CODE and returns the quotient.
875 Otherwise returns NULL_TREE. */
878 div_if_zero_remainder (enum tree_code code, const_tree arg1, const_tree arg2)
880 unsigned HOST_WIDE_INT int1l, int2l;
881 HOST_WIDE_INT int1h, int2h;
882 unsigned HOST_WIDE_INT quol, reml;
883 HOST_WIDE_INT quoh, remh;
884 tree type = TREE_TYPE (arg1);
885 int uns = TYPE_UNSIGNED (type);
887 int1l = TREE_INT_CST_LOW (arg1);
888 int1h = TREE_INT_CST_HIGH (arg1);
889 /* &obj[0] + -128 really should be compiled as &obj[-8] rather than
890 &obj[some_exotic_number]. */
891 if (POINTER_TYPE_P (type))
894 type = signed_type_for (type);
895 fit_double_type (int1l, int1h, &int1l, &int1h,
899 fit_double_type (int1l, int1h, &int1l, &int1h, type);
900 int2l = TREE_INT_CST_LOW (arg2);
901 int2h = TREE_INT_CST_HIGH (arg2);
903 div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
904 &quol, &quoh, &reml, &remh);
905 if (remh != 0 || reml != 0)
908 return build_int_cst_wide (type, quol, quoh);
911 /* This is nonzero if we should defer warnings about undefined
912 overflow. This facility exists because these warnings are a
913 special case. The code to estimate loop iterations does not want
914 to issue any warnings, since it works with expressions which do not
915 occur in user code. Various bits of cleanup code call fold(), but
916 only use the result if it has certain characteristics (e.g., is a
917 constant); that code only wants to issue a warning if the result is
920 static int fold_deferring_overflow_warnings;
922 /* If a warning about undefined overflow is deferred, this is the
923 warning. Note that this may cause us to turn two warnings into
924 one, but that is fine since it is sufficient to only give one
925 warning per expression. */
927 static const char* fold_deferred_overflow_warning;
929 /* If a warning about undefined overflow is deferred, this is the
930 level at which the warning should be emitted. */
932 static enum warn_strict_overflow_code fold_deferred_overflow_code;
934 /* Start deferring overflow warnings. We could use a stack here to
935 permit nested calls, but at present it is not necessary. */
938 fold_defer_overflow_warnings (void)
940 ++fold_deferring_overflow_warnings;
943 /* Stop deferring overflow warnings. If there is a pending warning,
944 and ISSUE is true, then issue the warning if appropriate. STMT is
945 the statement with which the warning should be associated (used for
946 location information); STMT may be NULL. CODE is the level of the
947 warning--a warn_strict_overflow_code value. This function will use
948 the smaller of CODE and the deferred code when deciding whether to
949 issue the warning. CODE may be zero to mean to always use the
953 fold_undefer_overflow_warnings (bool issue, const_gimple stmt, int code)
958 gcc_assert (fold_deferring_overflow_warnings > 0);
959 --fold_deferring_overflow_warnings;
960 if (fold_deferring_overflow_warnings > 0)
962 if (fold_deferred_overflow_warning != NULL
964 && code < (int) fold_deferred_overflow_code)
965 fold_deferred_overflow_code = (enum warn_strict_overflow_code) code;
969 warnmsg = fold_deferred_overflow_warning;
970 fold_deferred_overflow_warning = NULL;
972 if (!issue || warnmsg == NULL)
975 if (gimple_no_warning_p (stmt))
978 /* Use the smallest code level when deciding to issue the
980 if (code == 0 || code > (int) fold_deferred_overflow_code)
981 code = fold_deferred_overflow_code;
983 if (!issue_strict_overflow_warning (code))
987 locus = input_location;
989 locus = gimple_location (stmt);
990 warning_at (locus, OPT_Wstrict_overflow, "%s", warnmsg);
993 /* Stop deferring overflow warnings, ignoring any deferred
997 fold_undefer_and_ignore_overflow_warnings (void)
999 fold_undefer_overflow_warnings (false, NULL, 0);
1002 /* Whether we are deferring overflow warnings. */
1005 fold_deferring_overflow_warnings_p (void)
1007 return fold_deferring_overflow_warnings > 0;
1010 /* This is called when we fold something based on the fact that signed
1011 overflow is undefined. */
1014 fold_overflow_warning (const char* gmsgid, enum warn_strict_overflow_code wc)
1016 if (fold_deferring_overflow_warnings > 0)
1018 if (fold_deferred_overflow_warning == NULL
1019 || wc < fold_deferred_overflow_code)
1021 fold_deferred_overflow_warning = gmsgid;
1022 fold_deferred_overflow_code = wc;
1025 else if (issue_strict_overflow_warning (wc))
1026 warning (OPT_Wstrict_overflow, gmsgid);
1029 /* Return true if the built-in mathematical function specified by CODE
1030 is odd, i.e. -f(x) == f(-x). */
1033 negate_mathfn_p (enum built_in_function code)
1037 CASE_FLT_FN (BUILT_IN_ASIN):
1038 CASE_FLT_FN (BUILT_IN_ASINH):
1039 CASE_FLT_FN (BUILT_IN_ATAN):
1040 CASE_FLT_FN (BUILT_IN_ATANH):
1041 CASE_FLT_FN (BUILT_IN_CASIN):
1042 CASE_FLT_FN (BUILT_IN_CASINH):
1043 CASE_FLT_FN (BUILT_IN_CATAN):
1044 CASE_FLT_FN (BUILT_IN_CATANH):
1045 CASE_FLT_FN (BUILT_IN_CBRT):
1046 CASE_FLT_FN (BUILT_IN_CPROJ):
1047 CASE_FLT_FN (BUILT_IN_CSIN):
1048 CASE_FLT_FN (BUILT_IN_CSINH):
1049 CASE_FLT_FN (BUILT_IN_CTAN):
1050 CASE_FLT_FN (BUILT_IN_CTANH):
1051 CASE_FLT_FN (BUILT_IN_ERF):
1052 CASE_FLT_FN (BUILT_IN_LLROUND):
1053 CASE_FLT_FN (BUILT_IN_LROUND):
1054 CASE_FLT_FN (BUILT_IN_ROUND):
1055 CASE_FLT_FN (BUILT_IN_SIN):
1056 CASE_FLT_FN (BUILT_IN_SINH):
1057 CASE_FLT_FN (BUILT_IN_TAN):
1058 CASE_FLT_FN (BUILT_IN_TANH):
1059 CASE_FLT_FN (BUILT_IN_TRUNC):
1062 CASE_FLT_FN (BUILT_IN_LLRINT):
1063 CASE_FLT_FN (BUILT_IN_LRINT):
1064 CASE_FLT_FN (BUILT_IN_NEARBYINT):
1065 CASE_FLT_FN (BUILT_IN_RINT):
1066 return !flag_rounding_math;
1074 /* Check whether we may negate an integer constant T without causing
1078 may_negate_without_overflow_p (const_tree t)
1080 unsigned HOST_WIDE_INT val;
1084 gcc_assert (TREE_CODE (t) == INTEGER_CST);
1086 type = TREE_TYPE (t);
1087 if (TYPE_UNSIGNED (type))
1090 prec = TYPE_PRECISION (type);
1091 if (prec > HOST_BITS_PER_WIDE_INT)
1093 if (TREE_INT_CST_LOW (t) != 0)
1095 prec -= HOST_BITS_PER_WIDE_INT;
1096 val = TREE_INT_CST_HIGH (t);
1099 val = TREE_INT_CST_LOW (t);
1100 if (prec < HOST_BITS_PER_WIDE_INT)
1101 val &= ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
1102 return val != ((unsigned HOST_WIDE_INT) 1 << (prec - 1));
1105 /* Determine whether an expression T can be cheaply negated using
1106 the function negate_expr without introducing undefined overflow. */
1109 negate_expr_p (tree t)
1116 type = TREE_TYPE (t);
1118 STRIP_SIGN_NOPS (t);
1119 switch (TREE_CODE (t))
1122 if (TYPE_OVERFLOW_WRAPS (type))
1125 /* Check that -CST will not overflow type. */
1126 return may_negate_without_overflow_p (t);
1128 return (INTEGRAL_TYPE_P (type)
1129 && TYPE_OVERFLOW_WRAPS (type));
1137 return negate_expr_p (TREE_REALPART (t))
1138 && negate_expr_p (TREE_IMAGPART (t));
1141 return negate_expr_p (TREE_OPERAND (t, 0))
1142 && negate_expr_p (TREE_OPERAND (t, 1));
1145 return negate_expr_p (TREE_OPERAND (t, 0));
1148 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1149 || HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1151 /* -(A + B) -> (-B) - A. */
1152 if (negate_expr_p (TREE_OPERAND (t, 1))
1153 && reorder_operands_p (TREE_OPERAND (t, 0),
1154 TREE_OPERAND (t, 1)))
1156 /* -(A + B) -> (-A) - B. */
1157 return negate_expr_p (TREE_OPERAND (t, 0));
1160 /* We can't turn -(A-B) into B-A when we honor signed zeros. */
1161 return !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1162 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1163 && reorder_operands_p (TREE_OPERAND (t, 0),
1164 TREE_OPERAND (t, 1));
1167 if (TYPE_UNSIGNED (TREE_TYPE (t)))
1173 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (t))))
1174 return negate_expr_p (TREE_OPERAND (t, 1))
1175 || negate_expr_p (TREE_OPERAND (t, 0));
1178 case TRUNC_DIV_EXPR:
1179 case ROUND_DIV_EXPR:
1180 case FLOOR_DIV_EXPR:
1182 case EXACT_DIV_EXPR:
1183 /* In general we can't negate A / B, because if A is INT_MIN and
1184 B is 1, we may turn this into INT_MIN / -1 which is undefined
1185 and actually traps on some architectures. But if overflow is
1186 undefined, we can negate, because - (INT_MIN / 1) is an
1188 if (INTEGRAL_TYPE_P (TREE_TYPE (t))
1189 && !TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t)))
1191 return negate_expr_p (TREE_OPERAND (t, 1))
1192 || negate_expr_p (TREE_OPERAND (t, 0));
1195 /* Negate -((double)float) as (double)(-float). */
1196 if (TREE_CODE (type) == REAL_TYPE)
1198 tree tem = strip_float_extensions (t);
1200 return negate_expr_p (tem);
1205 /* Negate -f(x) as f(-x). */
1206 if (negate_mathfn_p (builtin_mathfn_code (t)))
1207 return negate_expr_p (CALL_EXPR_ARG (t, 0));
1211 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1212 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1214 tree op1 = TREE_OPERAND (t, 1);
1215 if (TREE_INT_CST_HIGH (op1) == 0
1216 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1217 == TREE_INT_CST_LOW (op1))
1228 /* Given T, an expression, return a folded tree for -T or NULL_TREE, if no
1229 simplification is possible.
1230 If negate_expr_p would return true for T, NULL_TREE will never be
1234 fold_negate_expr (location_t loc, tree t)
1236 tree type = TREE_TYPE (t);
1239 switch (TREE_CODE (t))
1241 /* Convert - (~A) to A + 1. */
1243 if (INTEGRAL_TYPE_P (type))
1244 return fold_build2_loc (loc, PLUS_EXPR, type, TREE_OPERAND (t, 0),
1245 build_int_cst (type, 1));
1249 tem = fold_negate_const (t, type);
1250 if (TREE_OVERFLOW (tem) == TREE_OVERFLOW (t)
1251 || !TYPE_OVERFLOW_TRAPS (type))
1256 tem = fold_negate_const (t, type);
1257 /* Two's complement FP formats, such as c4x, may overflow. */
1258 if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1263 tem = fold_negate_const (t, type);
1268 tree rpart = negate_expr (TREE_REALPART (t));
1269 tree ipart = negate_expr (TREE_IMAGPART (t));
1271 if ((TREE_CODE (rpart) == REAL_CST
1272 && TREE_CODE (ipart) == REAL_CST)
1273 || (TREE_CODE (rpart) == INTEGER_CST
1274 && TREE_CODE (ipart) == INTEGER_CST))
1275 return build_complex (type, rpart, ipart);
1280 if (negate_expr_p (t))
1281 return fold_build2_loc (loc, COMPLEX_EXPR, type,
1282 fold_negate_expr (loc, TREE_OPERAND (t, 0)),
1283 fold_negate_expr (loc, TREE_OPERAND (t, 1)));
1287 if (negate_expr_p (t))
1288 return fold_build1_loc (loc, CONJ_EXPR, type,
1289 fold_negate_expr (loc, TREE_OPERAND (t, 0)));
1293 return TREE_OPERAND (t, 0);
1296 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1297 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
1299 /* -(A + B) -> (-B) - A. */
1300 if (negate_expr_p (TREE_OPERAND (t, 1))
1301 && reorder_operands_p (TREE_OPERAND (t, 0),
1302 TREE_OPERAND (t, 1)))
1304 tem = negate_expr (TREE_OPERAND (t, 1));
1305 return fold_build2_loc (loc, MINUS_EXPR, type,
1306 tem, TREE_OPERAND (t, 0));
1309 /* -(A + B) -> (-A) - B. */
1310 if (negate_expr_p (TREE_OPERAND (t, 0)))
1312 tem = negate_expr (TREE_OPERAND (t, 0));
1313 return fold_build2_loc (loc, MINUS_EXPR, type,
1314 tem, TREE_OPERAND (t, 1));
1320 /* - (A - B) -> B - A */
1321 if (!HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type))
1322 && !HONOR_SIGNED_ZEROS (TYPE_MODE (type))
1323 && reorder_operands_p (TREE_OPERAND (t, 0), TREE_OPERAND (t, 1)))
1324 return fold_build2_loc (loc, MINUS_EXPR, type,
1325 TREE_OPERAND (t, 1), TREE_OPERAND (t, 0));
1329 if (TYPE_UNSIGNED (type))
1335 if (! HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type)))
1337 tem = TREE_OPERAND (t, 1);
1338 if (negate_expr_p (tem))
1339 return fold_build2_loc (loc, TREE_CODE (t), type,
1340 TREE_OPERAND (t, 0), negate_expr (tem));
1341 tem = TREE_OPERAND (t, 0);
1342 if (negate_expr_p (tem))
1343 return fold_build2_loc (loc, TREE_CODE (t), type,
1344 negate_expr (tem), TREE_OPERAND (t, 1));
1348 case TRUNC_DIV_EXPR:
1349 case ROUND_DIV_EXPR:
1350 case FLOOR_DIV_EXPR:
1352 case EXACT_DIV_EXPR:
1353 /* In general we can't negate A / B, because if A is INT_MIN and
1354 B is 1, we may turn this into INT_MIN / -1 which is undefined
1355 and actually traps on some architectures. But if overflow is
1356 undefined, we can negate, because - (INT_MIN / 1) is an
1358 if (!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
1360 const char * const warnmsg = G_("assuming signed overflow does not "
1361 "occur when negating a division");
1362 tem = TREE_OPERAND (t, 1);
1363 if (negate_expr_p (tem))
1365 if (INTEGRAL_TYPE_P (type)
1366 && (TREE_CODE (tem) != INTEGER_CST
1367 || integer_onep (tem)))
1368 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1369 return fold_build2_loc (loc, TREE_CODE (t), type,
1370 TREE_OPERAND (t, 0), negate_expr (tem));
1372 tem = TREE_OPERAND (t, 0);
1373 if (negate_expr_p (tem))
1375 if (INTEGRAL_TYPE_P (type)
1376 && (TREE_CODE (tem) != INTEGER_CST
1377 || tree_int_cst_equal (tem, TYPE_MIN_VALUE (type))))
1378 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MISC);
1379 return fold_build2_loc (loc, TREE_CODE (t), type,
1380 negate_expr (tem), TREE_OPERAND (t, 1));
1386 /* Convert -((double)float) into (double)(-float). */
1387 if (TREE_CODE (type) == REAL_TYPE)
1389 tem = strip_float_extensions (t);
1390 if (tem != t && negate_expr_p (tem))
1391 return fold_convert_loc (loc, type, negate_expr (tem));
1396 /* Negate -f(x) as f(-x). */
1397 if (negate_mathfn_p (builtin_mathfn_code (t))
1398 && negate_expr_p (CALL_EXPR_ARG (t, 0)))
1402 fndecl = get_callee_fndecl (t);
1403 arg = negate_expr (CALL_EXPR_ARG (t, 0));
1404 return build_call_expr_loc (loc, fndecl, 1, arg);
1409 /* Optimize -((int)x >> 31) into (unsigned)x >> 31. */
1410 if (TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST)
1412 tree op1 = TREE_OPERAND (t, 1);
1413 if (TREE_INT_CST_HIGH (op1) == 0
1414 && (unsigned HOST_WIDE_INT) (TYPE_PRECISION (type) - 1)
1415 == TREE_INT_CST_LOW (op1))
1417 tree ntype = TYPE_UNSIGNED (type)
1418 ? signed_type_for (type)
1419 : unsigned_type_for (type);
1420 tree temp = fold_convert_loc (loc, ntype, TREE_OPERAND (t, 0));
1421 temp = fold_build2_loc (loc, RSHIFT_EXPR, ntype, temp, op1);
1422 return fold_convert_loc (loc, type, temp);
1434 /* Like fold_negate_expr, but return a NEGATE_EXPR tree, if T can not be
1435 negated in a simpler way. Also allow for T to be NULL_TREE, in which case
1436 return NULL_TREE. */
1439 negate_expr (tree t)
1447 loc = EXPR_LOCATION (t);
1448 type = TREE_TYPE (t);
1449 STRIP_SIGN_NOPS (t);
1451 tem = fold_negate_expr (loc, t);
1454 tem = build1 (NEGATE_EXPR, TREE_TYPE (t), t);
1455 SET_EXPR_LOCATION (tem, loc);
1457 return fold_convert_loc (loc, type, tem);
1460 /* Split a tree IN into a constant, literal and variable parts that could be
1461 combined with CODE to make IN. "constant" means an expression with
1462 TREE_CONSTANT but that isn't an actual constant. CODE must be a
1463 commutative arithmetic operation. Store the constant part into *CONP,
1464 the literal in *LITP and return the variable part. If a part isn't
1465 present, set it to null. If the tree does not decompose in this way,
1466 return the entire tree as the variable part and the other parts as null.
1468 If CODE is PLUS_EXPR we also split trees that use MINUS_EXPR. In that
1469 case, we negate an operand that was subtracted. Except if it is a
1470 literal for which we use *MINUS_LITP instead.
1472 If NEGATE_P is true, we are negating all of IN, again except a literal
1473 for which we use *MINUS_LITP instead.
1475 If IN is itself a literal or constant, return it as appropriate.
1477 Note that we do not guarantee that any of the three values will be the
1478 same type as IN, but they will have the same signedness and mode. */
1481 split_tree (tree in, enum tree_code code, tree *conp, tree *litp,
1482 tree *minus_litp, int negate_p)
1490 /* Strip any conversions that don't change the machine mode or signedness. */
1491 STRIP_SIGN_NOPS (in);
1493 if (TREE_CODE (in) == INTEGER_CST || TREE_CODE (in) == REAL_CST
1494 || TREE_CODE (in) == FIXED_CST)
1496 else if (TREE_CODE (in) == code
1497 || ((! FLOAT_TYPE_P (TREE_TYPE (in)) || flag_associative_math)
1498 && ! SAT_FIXED_POINT_TYPE_P (TREE_TYPE (in))
1499 /* We can associate addition and subtraction together (even
1500 though the C standard doesn't say so) for integers because
1501 the value is not affected. For reals, the value might be
1502 affected, so we can't. */
1503 && ((code == PLUS_EXPR && TREE_CODE (in) == MINUS_EXPR)
1504 || (code == MINUS_EXPR && TREE_CODE (in) == PLUS_EXPR))))
1506 tree op0 = TREE_OPERAND (in, 0);
1507 tree op1 = TREE_OPERAND (in, 1);
1508 int neg1_p = TREE_CODE (in) == MINUS_EXPR;
1509 int neg_litp_p = 0, neg_conp_p = 0, neg_var_p = 0;
1511 /* First see if either of the operands is a literal, then a constant. */
1512 if (TREE_CODE (op0) == INTEGER_CST || TREE_CODE (op0) == REAL_CST
1513 || TREE_CODE (op0) == FIXED_CST)
1514 *litp = op0, op0 = 0;
1515 else if (TREE_CODE (op1) == INTEGER_CST || TREE_CODE (op1) == REAL_CST
1516 || TREE_CODE (op1) == FIXED_CST)
1517 *litp = op1, neg_litp_p = neg1_p, op1 = 0;
1519 if (op0 != 0 && TREE_CONSTANT (op0))
1520 *conp = op0, op0 = 0;
1521 else if (op1 != 0 && TREE_CONSTANT (op1))
1522 *conp = op1, neg_conp_p = neg1_p, op1 = 0;
1524 /* If we haven't dealt with either operand, this is not a case we can
1525 decompose. Otherwise, VAR is either of the ones remaining, if any. */
1526 if (op0 != 0 && op1 != 0)
1531 var = op1, neg_var_p = neg1_p;
1533 /* Now do any needed negations. */
1535 *minus_litp = *litp, *litp = 0;
1537 *conp = negate_expr (*conp);
1539 var = negate_expr (var);
1541 else if (TREE_CONSTANT (in))
1549 *minus_litp = *litp, *litp = 0;
1550 else if (*minus_litp)
1551 *litp = *minus_litp, *minus_litp = 0;
1552 *conp = negate_expr (*conp);
1553 var = negate_expr (var);
1559 /* Re-associate trees split by the above function. T1 and T2 are
1560 either expressions to associate or null. Return the new
1561 expression, if any. LOC is the location of the new expression. If
1562 we build an operation, do it in TYPE and with CODE. */
1565 associate_trees (location_t loc, tree t1, tree t2, enum tree_code code, tree type)
1574 /* If either input is CODE, a PLUS_EXPR, or a MINUS_EXPR, don't
1575 try to fold this since we will have infinite recursion. But do
1576 deal with any NEGATE_EXPRs. */
1577 if (TREE_CODE (t1) == code || TREE_CODE (t2) == code
1578 || TREE_CODE (t1) == MINUS_EXPR || TREE_CODE (t2) == MINUS_EXPR)
1580 if (code == PLUS_EXPR)
1582 if (TREE_CODE (t1) == NEGATE_EXPR)
1583 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t2),
1584 fold_convert_loc (loc, type, TREE_OPERAND (t1, 0)));
1585 else if (TREE_CODE (t2) == NEGATE_EXPR)
1586 tem = build2 (MINUS_EXPR, type, fold_convert_loc (loc, type, t1),
1587 fold_convert_loc (loc, type, TREE_OPERAND (t2, 0)));
1588 else if (integer_zerop (t2))
1589 return fold_convert_loc (loc, type, t1);
1591 else if (code == MINUS_EXPR)
1593 if (integer_zerop (t2))
1594 return fold_convert_loc (loc, type, t1);
1597 tem = build2 (code, type, fold_convert_loc (loc, type, t1),
1598 fold_convert_loc (loc, type, t2));
1599 goto associate_trees_exit;
1602 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, t1),
1603 fold_convert_loc (loc, type, t2));
1604 associate_trees_exit:
1605 protected_set_expr_location (tem, loc);
1609 /* Check whether TYPE1 and TYPE2 are equivalent integer types, suitable
1610 for use in int_const_binop, size_binop and size_diffop. */
1613 int_binop_types_match_p (enum tree_code code, const_tree type1, const_tree type2)
1615 if (TREE_CODE (type1) != INTEGER_TYPE && !POINTER_TYPE_P (type1))
1617 if (TREE_CODE (type2) != INTEGER_TYPE && !POINTER_TYPE_P (type2))
1632 return TYPE_UNSIGNED (type1) == TYPE_UNSIGNED (type2)
1633 && TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
1634 && TYPE_MODE (type1) == TYPE_MODE (type2);
1638 /* Combine two integer constants ARG1 and ARG2 under operation CODE
1639 to produce a new constant. Return NULL_TREE if we don't know how
1640 to evaluate CODE at compile-time.
1642 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1645 int_const_binop (enum tree_code code, const_tree arg1, const_tree arg2, int notrunc)
1647 unsigned HOST_WIDE_INT int1l, int2l;
1648 HOST_WIDE_INT int1h, int2h;
1649 unsigned HOST_WIDE_INT low;
1651 unsigned HOST_WIDE_INT garbagel;
1652 HOST_WIDE_INT garbageh;
1654 tree type = TREE_TYPE (arg1);
1655 int uns = TYPE_UNSIGNED (type);
1657 = (TREE_CODE (type) == INTEGER_TYPE && TYPE_IS_SIZETYPE (type));
1660 int1l = TREE_INT_CST_LOW (arg1);
1661 int1h = TREE_INT_CST_HIGH (arg1);
1662 int2l = TREE_INT_CST_LOW (arg2);
1663 int2h = TREE_INT_CST_HIGH (arg2);
1668 low = int1l | int2l, hi = int1h | int2h;
1672 low = int1l ^ int2l, hi = int1h ^ int2h;
1676 low = int1l & int2l, hi = int1h & int2h;
1682 /* It's unclear from the C standard whether shifts can overflow.
1683 The following code ignores overflow; perhaps a C standard
1684 interpretation ruling is needed. */
1685 lshift_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1692 lrotate_double (int1l, int1h, int2l, TYPE_PRECISION (type),
1697 overflow = add_double (int1l, int1h, int2l, int2h, &low, &hi);
1701 neg_double (int2l, int2h, &low, &hi);
1702 add_double (int1l, int1h, low, hi, &low, &hi);
1703 overflow = OVERFLOW_SUM_SIGN (hi, int2h, int1h);
1707 overflow = mul_double (int1l, int1h, int2l, int2h, &low, &hi);
1710 case TRUNC_DIV_EXPR:
1711 case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
1712 case EXACT_DIV_EXPR:
1713 /* This is a shortcut for a common special case. */
1714 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1715 && !TREE_OVERFLOW (arg1)
1716 && !TREE_OVERFLOW (arg2)
1717 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1719 if (code == CEIL_DIV_EXPR)
1722 low = int1l / int2l, hi = 0;
1726 /* ... fall through ... */
1728 case ROUND_DIV_EXPR:
1729 if (int2h == 0 && int2l == 0)
1731 if (int2h == 0 && int2l == 1)
1733 low = int1l, hi = int1h;
1736 if (int1l == int2l && int1h == int2h
1737 && ! (int1l == 0 && int1h == 0))
1742 overflow = div_and_round_double (code, uns, int1l, int1h, int2l, int2h,
1743 &low, &hi, &garbagel, &garbageh);
1746 case TRUNC_MOD_EXPR:
1747 case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR:
1748 /* This is a shortcut for a common special case. */
1749 if (int2h == 0 && (HOST_WIDE_INT) int2l > 0
1750 && !TREE_OVERFLOW (arg1)
1751 && !TREE_OVERFLOW (arg2)
1752 && int1h == 0 && (HOST_WIDE_INT) int1l >= 0)
1754 if (code == CEIL_MOD_EXPR)
1756 low = int1l % int2l, hi = 0;
1760 /* ... fall through ... */
1762 case ROUND_MOD_EXPR:
1763 if (int2h == 0 && int2l == 0)
1765 overflow = div_and_round_double (code, uns,
1766 int1l, int1h, int2l, int2h,
1767 &garbagel, &garbageh, &low, &hi);
1773 low = (((unsigned HOST_WIDE_INT) int1h
1774 < (unsigned HOST_WIDE_INT) int2h)
1775 || (((unsigned HOST_WIDE_INT) int1h
1776 == (unsigned HOST_WIDE_INT) int2h)
1779 low = (int1h < int2h
1780 || (int1h == int2h && int1l < int2l));
1782 if (low == (code == MIN_EXPR))
1783 low = int1l, hi = int1h;
1785 low = int2l, hi = int2h;
1794 t = build_int_cst_wide (TREE_TYPE (arg1), low, hi);
1796 /* Propagate overflow flags ourselves. */
1797 if (((!uns || is_sizetype) && overflow)
1798 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1801 TREE_OVERFLOW (t) = 1;
1805 t = force_fit_type_double (TREE_TYPE (arg1), low, hi, 1,
1806 ((!uns || is_sizetype) && overflow)
1807 | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2));
1812 /* Combine two constants ARG1 and ARG2 under operation CODE to produce a new
1813 constant. We assume ARG1 and ARG2 have the same data type, or at least
1814 are the same kind of constant and the same machine mode. Return zero if
1815 combining the constants is not allowed in the current operating mode.
1817 If NOTRUNC is nonzero, do not truncate the result to fit the data type. */
1820 const_binop (enum tree_code code, tree arg1, tree arg2, int notrunc)
1822 /* Sanity check for the recursive cases. */
1829 if (TREE_CODE (arg1) == INTEGER_CST)
1830 return int_const_binop (code, arg1, arg2, notrunc);
1832 if (TREE_CODE (arg1) == REAL_CST)
1834 enum machine_mode mode;
1837 REAL_VALUE_TYPE value;
1838 REAL_VALUE_TYPE result;
1842 /* The following codes are handled by real_arithmetic. */
1857 d1 = TREE_REAL_CST (arg1);
1858 d2 = TREE_REAL_CST (arg2);
1860 type = TREE_TYPE (arg1);
1861 mode = TYPE_MODE (type);
1863 /* Don't perform operation if we honor signaling NaNs and
1864 either operand is a NaN. */
1865 if (HONOR_SNANS (mode)
1866 && (REAL_VALUE_ISNAN (d1) || REAL_VALUE_ISNAN (d2)))
1869 /* Don't perform operation if it would raise a division
1870 by zero exception. */
1871 if (code == RDIV_EXPR
1872 && REAL_VALUES_EQUAL (d2, dconst0)
1873 && (flag_trapping_math || ! MODE_HAS_INFINITIES (mode)))
1876 /* If either operand is a NaN, just return it. Otherwise, set up
1877 for floating-point trap; we return an overflow. */
1878 if (REAL_VALUE_ISNAN (d1))
1880 else if (REAL_VALUE_ISNAN (d2))
1883 inexact = real_arithmetic (&value, code, &d1, &d2);
1884 real_convert (&result, mode, &value);
1886 /* Don't constant fold this floating point operation if
1887 the result has overflowed and flag_trapping_math. */
1888 if (flag_trapping_math
1889 && MODE_HAS_INFINITIES (mode)
1890 && REAL_VALUE_ISINF (result)
1891 && !REAL_VALUE_ISINF (d1)
1892 && !REAL_VALUE_ISINF (d2))
1895 /* Don't constant fold this floating point operation if the
1896 result may dependent upon the run-time rounding mode and
1897 flag_rounding_math is set, or if GCC's software emulation
1898 is unable to accurately represent the result. */
1899 if ((flag_rounding_math
1900 || (MODE_COMPOSITE_P (mode) && !flag_unsafe_math_optimizations))
1901 && (inexact || !real_identical (&result, &value)))
1904 t = build_real (type, result);
1906 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2);
1910 if (TREE_CODE (arg1) == FIXED_CST)
1912 FIXED_VALUE_TYPE f1;
1913 FIXED_VALUE_TYPE f2;
1914 FIXED_VALUE_TYPE result;
1919 /* The following codes are handled by fixed_arithmetic. */
1925 case TRUNC_DIV_EXPR:
1926 f2 = TREE_FIXED_CST (arg2);
1931 f2.data.high = TREE_INT_CST_HIGH (arg2);
1932 f2.data.low = TREE_INT_CST_LOW (arg2);
1940 f1 = TREE_FIXED_CST (arg1);
1941 type = TREE_TYPE (arg1);
1942 sat_p = TYPE_SATURATING (type);
1943 overflow_p = fixed_arithmetic (&result, code, &f1, &f2, sat_p);
1944 t = build_fixed (type, result);
1945 /* Propagate overflow flags. */
1946 if (overflow_p | TREE_OVERFLOW (arg1) | TREE_OVERFLOW (arg2))
1947 TREE_OVERFLOW (t) = 1;
1951 if (TREE_CODE (arg1) == COMPLEX_CST)
1953 tree type = TREE_TYPE (arg1);
1954 tree r1 = TREE_REALPART (arg1);
1955 tree i1 = TREE_IMAGPART (arg1);
1956 tree r2 = TREE_REALPART (arg2);
1957 tree i2 = TREE_IMAGPART (arg2);
1964 real = const_binop (code, r1, r2, notrunc);
1965 imag = const_binop (code, i1, i2, notrunc);
1970 if (COMPLEX_FLOAT_TYPE_P (type))
1971 return do_mpc_arg2 (arg1, arg2, type,
1972 /* do_nonfinite= */ folding_initializer,
1976 real = const_binop (MINUS_EXPR,
1977 const_binop (MULT_EXPR, r1, r2, notrunc),
1978 const_binop (MULT_EXPR, i1, i2, notrunc),
1980 imag = const_binop (PLUS_EXPR,
1981 const_binop (MULT_EXPR, r1, i2, notrunc),
1982 const_binop (MULT_EXPR, i1, r2, notrunc),
1988 if (COMPLEX_FLOAT_TYPE_P (type))
1989 return do_mpc_arg2 (arg1, arg2, type,
1990 /* do_nonfinite= */ folding_initializer,
1995 case TRUNC_DIV_EXPR:
1997 case FLOOR_DIV_EXPR:
1998 case ROUND_DIV_EXPR:
1999 if (flag_complex_method == 0)
2001 /* Keep this algorithm in sync with
2002 tree-complex.c:expand_complex_div_straight().
2004 Expand complex division to scalars, straightforward algorithm.
2005 a / b = ((ar*br + ai*bi)/t) + i((ai*br - ar*bi)/t)
2009 = const_binop (PLUS_EXPR,
2010 const_binop (MULT_EXPR, r2, r2, notrunc),
2011 const_binop (MULT_EXPR, i2, i2, notrunc),
2014 = const_binop (PLUS_EXPR,
2015 const_binop (MULT_EXPR, r1, r2, notrunc),
2016 const_binop (MULT_EXPR, i1, i2, notrunc),
2019 = const_binop (MINUS_EXPR,
2020 const_binop (MULT_EXPR, i1, r2, notrunc),
2021 const_binop (MULT_EXPR, r1, i2, notrunc),
2024 real = const_binop (code, t1, magsquared, notrunc);
2025 imag = const_binop (code, t2, magsquared, notrunc);
2029 /* Keep this algorithm in sync with
2030 tree-complex.c:expand_complex_div_wide().
2032 Expand complex division to scalars, modified algorithm to minimize
2033 overflow with wide input ranges. */
2034 tree inner_type = TREE_TYPE (type);
2035 tree absr2 = fold_build1 (ABS_EXPR, inner_type, r2);
2036 tree absi2 = fold_build1 (ABS_EXPR, inner_type, i2);
2037 tree compare = fold_build2 (LT_EXPR, boolean_type_node, absr2, absi2);
2038 if (integer_nonzerop (compare))
2040 /* In the TRUE branch, we compute
2042 div = (br * ratio) + bi;
2043 tr = (ar * ratio) + ai;
2044 ti = (ai * ratio) - ar;
2047 tree ratio = fold_build2 (code, inner_type, r2, i2);
2048 tree div = fold_build2 (PLUS_EXPR, inner_type, i2,
2049 fold_build2 (MULT_EXPR, inner_type,
2051 real = fold_build2 (MULT_EXPR, inner_type, r1, ratio);
2052 real = fold_build2 (PLUS_EXPR, inner_type, real, i1);
2053 real = fold_build2 (code, inner_type, real, div);
2055 imag = fold_build2 (MULT_EXPR, inner_type, i1, ratio);
2056 imag = fold_build2 (MINUS_EXPR, inner_type, imag, r1);
2057 imag = fold_build2 (code, inner_type, imag, div);
2061 /* In the FALSE branch, we compute
2063 divisor = (d * ratio) + c;
2064 tr = (b * ratio) + a;
2065 ti = b - (a * ratio);
2068 tree ratio = fold_build2 (code, inner_type, i2, r2);
2069 tree div = fold_build2 (PLUS_EXPR, inner_type, r2,
2070 fold_build2 (MULT_EXPR, inner_type,
2073 real = fold_build2 (MULT_EXPR, inner_type, i1, ratio);
2074 real = fold_build2 (PLUS_EXPR, inner_type, real, r1);
2075 real = fold_build2 (code, inner_type, real, div);
2077 imag = fold_build2 (MULT_EXPR, inner_type, r1, ratio);
2078 imag = fold_build2 (MINUS_EXPR, inner_type, i1, imag);
2079 imag = fold_build2 (code, inner_type, imag, div);
2089 return build_complex (type, real, imag);
2092 if (TREE_CODE (arg1) == VECTOR_CST)
2094 tree type = TREE_TYPE(arg1);
2095 int count = TYPE_VECTOR_SUBPARTS (type), i;
2096 tree elements1, elements2, list = NULL_TREE;
2098 if(TREE_CODE(arg2) != VECTOR_CST)
2101 elements1 = TREE_VECTOR_CST_ELTS (arg1);
2102 elements2 = TREE_VECTOR_CST_ELTS (arg2);
2104 for (i = 0; i < count; i++)
2106 tree elem1, elem2, elem;
2108 /* The trailing elements can be empty and should be treated as 0 */
2110 elem1 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2113 elem1 = TREE_VALUE(elements1);
2114 elements1 = TREE_CHAIN (elements1);
2118 elem2 = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2121 elem2 = TREE_VALUE(elements2);
2122 elements2 = TREE_CHAIN (elements2);
2125 elem = const_binop (code, elem1, elem2, notrunc);
2127 /* It is possible that const_binop cannot handle the given
2128 code and return NULL_TREE */
2129 if(elem == NULL_TREE)
2132 list = tree_cons (NULL_TREE, elem, list);
2134 return build_vector(type, nreverse(list));
2139 /* Create a size type INT_CST node with NUMBER sign extended. KIND
2140 indicates which particular sizetype to create. */
2143 size_int_kind (HOST_WIDE_INT number, enum size_type_kind kind)
2145 return build_int_cst (sizetype_tab[(int) kind], number);
2148 /* Combine operands OP1 and OP2 with arithmetic operation CODE. CODE
2149 is a tree code. The type of the result is taken from the operands.
2150 Both must be equivalent integer types, ala int_binop_types_match_p.
2151 If the operands are constant, so is the result. */
2154 size_binop_loc (location_t loc, enum tree_code code, tree arg0, tree arg1)
2156 tree type = TREE_TYPE (arg0);
2158 if (arg0 == error_mark_node || arg1 == error_mark_node)
2159 return error_mark_node;
2161 gcc_assert (int_binop_types_match_p (code, TREE_TYPE (arg0),
2164 /* Handle the special case of two integer constants faster. */
2165 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
2167 /* And some specific cases even faster than that. */
2168 if (code == PLUS_EXPR)
2170 if (integer_zerop (arg0) && !TREE_OVERFLOW (arg0))
2172 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2175 else if (code == MINUS_EXPR)
2177 if (integer_zerop (arg1) && !TREE_OVERFLOW (arg1))
2180 else if (code == MULT_EXPR)
2182 if (integer_onep (arg0) && !TREE_OVERFLOW (arg0))
2186 /* Handle general case of two integer constants. */
2187 return int_const_binop (code, arg0, arg1, 0);
2190 return fold_build2_loc (loc, code, type, arg0, arg1);
2193 /* Given two values, either both of sizetype or both of bitsizetype,
2194 compute the difference between the two values. Return the value
2195 in signed type corresponding to the type of the operands. */
2198 size_diffop_loc (location_t loc, tree arg0, tree arg1)
2200 tree type = TREE_TYPE (arg0);
2203 gcc_assert (int_binop_types_match_p (MINUS_EXPR, TREE_TYPE (arg0),
2206 /* If the type is already signed, just do the simple thing. */
2207 if (!TYPE_UNSIGNED (type))
2208 return size_binop_loc (loc, MINUS_EXPR, arg0, arg1);
2210 if (type == sizetype)
2212 else if (type == bitsizetype)
2213 ctype = sbitsizetype;
2215 ctype = signed_type_for (type);
2217 /* If either operand is not a constant, do the conversions to the signed
2218 type and subtract. The hardware will do the right thing with any
2219 overflow in the subtraction. */
2220 if (TREE_CODE (arg0) != INTEGER_CST || TREE_CODE (arg1) != INTEGER_CST)
2221 return size_binop_loc (loc, MINUS_EXPR,
2222 fold_convert_loc (loc, ctype, arg0),
2223 fold_convert_loc (loc, ctype, arg1));
2225 /* If ARG0 is larger than ARG1, subtract and return the result in CTYPE.
2226 Otherwise, subtract the other way, convert to CTYPE (we know that can't
2227 overflow) and negate (which can't either). Special-case a result
2228 of zero while we're here. */
2229 if (tree_int_cst_equal (arg0, arg1))
2230 return build_int_cst (ctype, 0);
2231 else if (tree_int_cst_lt (arg1, arg0))
2232 return fold_convert_loc (loc, ctype,
2233 size_binop_loc (loc, MINUS_EXPR, arg0, arg1));
2235 return size_binop_loc (loc, MINUS_EXPR, build_int_cst (ctype, 0),
2236 fold_convert_loc (loc, ctype,
2237 size_binop_loc (loc,
2242 /* A subroutine of fold_convert_const handling conversions of an
2243 INTEGER_CST to another integer type. */
2246 fold_convert_const_int_from_int (tree type, const_tree arg1)
2250 /* Given an integer constant, make new constant with new type,
2251 appropriately sign-extended or truncated. */
2252 t = force_fit_type_double (type, TREE_INT_CST_LOW (arg1),
2253 TREE_INT_CST_HIGH (arg1),
2254 /* Don't set the overflow when
2255 converting from a pointer, */
2256 !POINTER_TYPE_P (TREE_TYPE (arg1))
2257 /* or to a sizetype with same signedness
2258 and the precision is unchanged.
2259 ??? sizetype is always sign-extended,
2260 but its signedness depends on the
2261 frontend. Thus we see spurious overflows
2262 here if we do not check this. */
2263 && !((TYPE_PRECISION (TREE_TYPE (arg1))
2264 == TYPE_PRECISION (type))
2265 && (TYPE_UNSIGNED (TREE_TYPE (arg1))
2266 == TYPE_UNSIGNED (type))
2267 && ((TREE_CODE (TREE_TYPE (arg1)) == INTEGER_TYPE
2268 && TYPE_IS_SIZETYPE (TREE_TYPE (arg1)))
2269 || (TREE_CODE (type) == INTEGER_TYPE
2270 && TYPE_IS_SIZETYPE (type)))),
2271 (TREE_INT_CST_HIGH (arg1) < 0
2272 && (TYPE_UNSIGNED (type)
2273 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2274 | TREE_OVERFLOW (arg1));
2279 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2280 to an integer type. */
2283 fold_convert_const_int_from_real (enum tree_code code, tree type, const_tree arg1)
2288 /* The following code implements the floating point to integer
2289 conversion rules required by the Java Language Specification,
2290 that IEEE NaNs are mapped to zero and values that overflow
2291 the target precision saturate, i.e. values greater than
2292 INT_MAX are mapped to INT_MAX, and values less than INT_MIN
2293 are mapped to INT_MIN. These semantics are allowed by the
2294 C and C++ standards that simply state that the behavior of
2295 FP-to-integer conversion is unspecified upon overflow. */
2297 HOST_WIDE_INT high, low;
2299 REAL_VALUE_TYPE x = TREE_REAL_CST (arg1);
2303 case FIX_TRUNC_EXPR:
2304 real_trunc (&r, VOIDmode, &x);
2311 /* If R is NaN, return zero and show we have an overflow. */
2312 if (REAL_VALUE_ISNAN (r))
2319 /* See if R is less than the lower bound or greater than the
2324 tree lt = TYPE_MIN_VALUE (type);
2325 REAL_VALUE_TYPE l = real_value_from_int_cst (NULL_TREE, lt);
2326 if (REAL_VALUES_LESS (r, l))
2329 high = TREE_INT_CST_HIGH (lt);
2330 low = TREE_INT_CST_LOW (lt);
2336 tree ut = TYPE_MAX_VALUE (type);
2339 REAL_VALUE_TYPE u = real_value_from_int_cst (NULL_TREE, ut);
2340 if (REAL_VALUES_LESS (u, r))
2343 high = TREE_INT_CST_HIGH (ut);
2344 low = TREE_INT_CST_LOW (ut);
2350 REAL_VALUE_TO_INT (&low, &high, r);
2352 t = force_fit_type_double (type, low, high, -1,
2353 overflow | TREE_OVERFLOW (arg1));
2357 /* A subroutine of fold_convert_const handling conversions of a
2358 FIXED_CST to an integer type. */
2361 fold_convert_const_int_from_fixed (tree type, const_tree arg1)
2364 double_int temp, temp_trunc;
2367 /* Right shift FIXED_CST to temp by fbit. */
2368 temp = TREE_FIXED_CST (arg1).data;
2369 mode = TREE_FIXED_CST (arg1).mode;
2370 if (GET_MODE_FBIT (mode) < 2 * HOST_BITS_PER_WIDE_INT)
2372 lshift_double (temp.low, temp.high,
2373 - GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2374 &temp.low, &temp.high, SIGNED_FIXED_POINT_MODE_P (mode));
2376 /* Left shift temp to temp_trunc by fbit. */
2377 lshift_double (temp.low, temp.high,
2378 GET_MODE_FBIT (mode), 2 * HOST_BITS_PER_WIDE_INT,
2379 &temp_trunc.low, &temp_trunc.high,
2380 SIGNED_FIXED_POINT_MODE_P (mode));
2387 temp_trunc.high = 0;
2390 /* If FIXED_CST is negative, we need to round the value toward 0.
2391 By checking if the fractional bits are not zero to add 1 to temp. */
2392 if (SIGNED_FIXED_POINT_MODE_P (mode) && temp_trunc.high < 0
2393 && !double_int_equal_p (TREE_FIXED_CST (arg1).data, temp_trunc))
2398 temp = double_int_add (temp, one);
2401 /* Given a fixed-point constant, make new constant with new type,
2402 appropriately sign-extended or truncated. */
2403 t = force_fit_type_double (type, temp.low, temp.high, -1,
2405 && (TYPE_UNSIGNED (type)
2406 < TYPE_UNSIGNED (TREE_TYPE (arg1))))
2407 | TREE_OVERFLOW (arg1));
2412 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2413 to another floating point type. */
2416 fold_convert_const_real_from_real (tree type, const_tree arg1)
2418 REAL_VALUE_TYPE value;
2421 real_convert (&value, TYPE_MODE (type), &TREE_REAL_CST (arg1));
2422 t = build_real (type, value);
2424 /* If converting an infinity or NAN to a representation that doesn't
2425 have one, set the overflow bit so that we can produce some kind of
2426 error message at the appropriate point if necessary. It's not the
2427 most user-friendly message, but it's better than nothing. */
2428 if (REAL_VALUE_ISINF (TREE_REAL_CST (arg1))
2429 && !MODE_HAS_INFINITIES (TYPE_MODE (type)))
2430 TREE_OVERFLOW (t) = 1;
2431 else if (REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
2432 && !MODE_HAS_NANS (TYPE_MODE (type)))
2433 TREE_OVERFLOW (t) = 1;
2434 /* Regular overflow, conversion produced an infinity in a mode that
2435 can't represent them. */
2436 else if (!MODE_HAS_INFINITIES (TYPE_MODE (type))
2437 && REAL_VALUE_ISINF (value)
2438 && !REAL_VALUE_ISINF (TREE_REAL_CST (arg1)))
2439 TREE_OVERFLOW (t) = 1;
2441 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2445 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2446 to a floating point type. */
2449 fold_convert_const_real_from_fixed (tree type, const_tree arg1)
2451 REAL_VALUE_TYPE value;
2454 real_convert_from_fixed (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1));
2455 t = build_real (type, value);
2457 TREE_OVERFLOW (t) = TREE_OVERFLOW (arg1);
2461 /* A subroutine of fold_convert_const handling conversions a FIXED_CST
2462 to another fixed-point type. */
2465 fold_convert_const_fixed_from_fixed (tree type, const_tree arg1)
2467 FIXED_VALUE_TYPE value;
2471 overflow_p = fixed_convert (&value, TYPE_MODE (type), &TREE_FIXED_CST (arg1),
2472 TYPE_SATURATING (type));
2473 t = build_fixed (type, value);
2475 /* Propagate overflow flags. */
2476 if (overflow_p | TREE_OVERFLOW (arg1))
2477 TREE_OVERFLOW (t) = 1;
2481 /* A subroutine of fold_convert_const handling conversions an INTEGER_CST
2482 to a fixed-point type. */
2485 fold_convert_const_fixed_from_int (tree type, const_tree arg1)
2487 FIXED_VALUE_TYPE value;
2491 overflow_p = fixed_convert_from_int (&value, TYPE_MODE (type),
2492 TREE_INT_CST (arg1),
2493 TYPE_UNSIGNED (TREE_TYPE (arg1)),
2494 TYPE_SATURATING (type));
2495 t = build_fixed (type, value);
2497 /* Propagate overflow flags. */
2498 if (overflow_p | TREE_OVERFLOW (arg1))
2499 TREE_OVERFLOW (t) = 1;
2503 /* A subroutine of fold_convert_const handling conversions a REAL_CST
2504 to a fixed-point type. */
2507 fold_convert_const_fixed_from_real (tree type, const_tree arg1)
2509 FIXED_VALUE_TYPE value;
2513 overflow_p = fixed_convert_from_real (&value, TYPE_MODE (type),
2514 &TREE_REAL_CST (arg1),
2515 TYPE_SATURATING (type));
2516 t = build_fixed (type, value);
2518 /* Propagate overflow flags. */
2519 if (overflow_p | TREE_OVERFLOW (arg1))
2520 TREE_OVERFLOW (t) = 1;
2524 /* Attempt to fold type conversion operation CODE of expression ARG1 to
2525 type TYPE. If no simplification can be done return NULL_TREE. */
2528 fold_convert_const (enum tree_code code, tree type, tree arg1)
2530 if (TREE_TYPE (arg1) == type)
2533 if (POINTER_TYPE_P (type) || INTEGRAL_TYPE_P (type)
2534 || TREE_CODE (type) == OFFSET_TYPE)
2536 if (TREE_CODE (arg1) == INTEGER_CST)
2537 return fold_convert_const_int_from_int (type, arg1);
2538 else if (TREE_CODE (arg1) == REAL_CST)
2539 return fold_convert_const_int_from_real (code, type, arg1);
2540 else if (TREE_CODE (arg1) == FIXED_CST)
2541 return fold_convert_const_int_from_fixed (type, arg1);
2543 else if (TREE_CODE (type) == REAL_TYPE)
2545 if (TREE_CODE (arg1) == INTEGER_CST)
2546 return build_real_from_int_cst (type, arg1);
2547 else if (TREE_CODE (arg1) == REAL_CST)
2548 return fold_convert_const_real_from_real (type, arg1);
2549 else if (TREE_CODE (arg1) == FIXED_CST)
2550 return fold_convert_const_real_from_fixed (type, arg1);
2552 else if (TREE_CODE (type) == FIXED_POINT_TYPE)
2554 if (TREE_CODE (arg1) == FIXED_CST)
2555 return fold_convert_const_fixed_from_fixed (type, arg1);
2556 else if (TREE_CODE (arg1) == INTEGER_CST)
2557 return fold_convert_const_fixed_from_int (type, arg1);
2558 else if (TREE_CODE (arg1) == REAL_CST)
2559 return fold_convert_const_fixed_from_real (type, arg1);
2564 /* Construct a vector of zero elements of vector type TYPE. */
2567 build_zero_vector (tree type)
2572 elem = fold_convert_const (NOP_EXPR, TREE_TYPE (type), integer_zero_node);
2573 units = TYPE_VECTOR_SUBPARTS (type);
2576 for (i = 0; i < units; i++)
2577 list = tree_cons (NULL_TREE, elem, list);
2578 return build_vector (type, list);
2581 /* Returns true, if ARG is convertible to TYPE using a NOP_EXPR. */
2584 fold_convertible_p (const_tree type, const_tree arg)
2586 tree orig = TREE_TYPE (arg);
2591 if (TREE_CODE (arg) == ERROR_MARK
2592 || TREE_CODE (type) == ERROR_MARK
2593 || TREE_CODE (orig) == ERROR_MARK)
2596 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2599 switch (TREE_CODE (type))
2601 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2602 case POINTER_TYPE: case REFERENCE_TYPE:
2604 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2605 || TREE_CODE (orig) == OFFSET_TYPE)
2607 return (TREE_CODE (orig) == VECTOR_TYPE
2608 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2611 case FIXED_POINT_TYPE:
2615 return TREE_CODE (type) == TREE_CODE (orig);
2622 /* Convert expression ARG to type TYPE. Used by the middle-end for
2623 simple conversions in preference to calling the front-end's convert. */
2626 fold_convert_loc (location_t loc, tree type, tree arg)
2628 tree orig = TREE_TYPE (arg);
2634 if (TREE_CODE (arg) == ERROR_MARK
2635 || TREE_CODE (type) == ERROR_MARK
2636 || TREE_CODE (orig) == ERROR_MARK)
2637 return error_mark_node;
2639 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (orig))
2640 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2642 switch (TREE_CODE (type))
2645 case REFERENCE_TYPE:
2646 /* Handle conversions between pointers to different address spaces. */
2647 if (POINTER_TYPE_P (orig)
2648 && (TYPE_ADDR_SPACE (TREE_TYPE (type))
2649 != TYPE_ADDR_SPACE (TREE_TYPE (orig))))
2650 return fold_build1_loc (loc, ADDR_SPACE_CONVERT_EXPR, type, arg);
2653 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
2655 if (TREE_CODE (arg) == INTEGER_CST)
2657 tem = fold_convert_const (NOP_EXPR, type, arg);
2658 if (tem != NULL_TREE)
2661 if (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2662 || TREE_CODE (orig) == OFFSET_TYPE)
2663 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2664 if (TREE_CODE (orig) == COMPLEX_TYPE)
2665 return fold_convert_loc (loc, type,
2666 fold_build1_loc (loc, REALPART_EXPR,
2667 TREE_TYPE (orig), arg));
2668 gcc_assert (TREE_CODE (orig) == VECTOR_TYPE
2669 && tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2670 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2673 if (TREE_CODE (arg) == INTEGER_CST)
2675 tem = fold_convert_const (FLOAT_EXPR, type, arg);
2676 if (tem != NULL_TREE)
2679 else if (TREE_CODE (arg) == REAL_CST)
2681 tem = fold_convert_const (NOP_EXPR, type, arg);
2682 if (tem != NULL_TREE)
2685 else if (TREE_CODE (arg) == FIXED_CST)
2687 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2688 if (tem != NULL_TREE)
2692 switch (TREE_CODE (orig))
2695 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2696 case POINTER_TYPE: case REFERENCE_TYPE:
2697 return fold_build1_loc (loc, FLOAT_EXPR, type, arg);
2700 return fold_build1_loc (loc, NOP_EXPR, type, arg);
2702 case FIXED_POINT_TYPE:
2703 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
2706 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2707 return fold_convert_loc (loc, type, tem);
2713 case FIXED_POINT_TYPE:
2714 if (TREE_CODE (arg) == FIXED_CST || TREE_CODE (arg) == INTEGER_CST
2715 || TREE_CODE (arg) == REAL_CST)
2717 tem = fold_convert_const (FIXED_CONVERT_EXPR, type, arg);
2718 if (tem != NULL_TREE)
2719 goto fold_convert_exit;
2722 switch (TREE_CODE (orig))
2724 case FIXED_POINT_TYPE:
2729 return fold_build1_loc (loc, FIXED_CONVERT_EXPR, type, arg);
2732 tem = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2733 return fold_convert_loc (loc, type, tem);
2740 switch (TREE_CODE (orig))
2743 case BOOLEAN_TYPE: case ENUMERAL_TYPE:
2744 case POINTER_TYPE: case REFERENCE_TYPE:
2746 case FIXED_POINT_TYPE:
2747 return fold_build2_loc (loc, COMPLEX_EXPR, type,
2748 fold_convert_loc (loc, TREE_TYPE (type), arg),
2749 fold_convert_loc (loc, TREE_TYPE (type),
2750 integer_zero_node));
2755 if (TREE_CODE (arg) == COMPLEX_EXPR)
2757 rpart = fold_convert_loc (loc, TREE_TYPE (type),
2758 TREE_OPERAND (arg, 0));
2759 ipart = fold_convert_loc (loc, TREE_TYPE (type),
2760 TREE_OPERAND (arg, 1));
2761 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2764 arg = save_expr (arg);
2765 rpart = fold_build1_loc (loc, REALPART_EXPR, TREE_TYPE (orig), arg);
2766 ipart = fold_build1_loc (loc, IMAGPART_EXPR, TREE_TYPE (orig), arg);
2767 rpart = fold_convert_loc (loc, TREE_TYPE (type), rpart);
2768 ipart = fold_convert_loc (loc, TREE_TYPE (type), ipart);
2769 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart, ipart);
2777 if (integer_zerop (arg))
2778 return build_zero_vector (type);
2779 gcc_assert (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (orig)));
2780 gcc_assert (INTEGRAL_TYPE_P (orig) || POINTER_TYPE_P (orig)
2781 || TREE_CODE (orig) == VECTOR_TYPE);
2782 return fold_build1_loc (loc, VIEW_CONVERT_EXPR, type, arg);
2785 tem = fold_ignored_result (arg);
2786 if (TREE_CODE (tem) == MODIFY_EXPR)
2787 goto fold_convert_exit;
2788 return fold_build1_loc (loc, NOP_EXPR, type, tem);
2794 protected_set_expr_location (tem, loc);
2798 /* Return false if expr can be assumed not to be an lvalue, true
2802 maybe_lvalue_p (const_tree x)
2804 /* We only need to wrap lvalue tree codes. */
2805 switch (TREE_CODE (x))
2816 case ALIGN_INDIRECT_REF:
2817 case MISALIGNED_INDIRECT_REF:
2819 case ARRAY_RANGE_REF:
2825 case PREINCREMENT_EXPR:
2826 case PREDECREMENT_EXPR:
2828 case TRY_CATCH_EXPR:
2829 case WITH_CLEANUP_EXPR:
2838 /* Assume the worst for front-end tree codes. */
2839 if ((int)TREE_CODE (x) >= NUM_TREE_CODES)
2847 /* Return an expr equal to X but certainly not valid as an lvalue. */
2850 non_lvalue_loc (location_t loc, tree x)
2852 /* While we are in GIMPLE, NON_LVALUE_EXPR doesn't mean anything to
2857 if (! maybe_lvalue_p (x))
2859 x = build1 (NON_LVALUE_EXPR, TREE_TYPE (x), x);
2860 SET_EXPR_LOCATION (x, loc);
2864 /* Nonzero means lvalues are limited to those valid in pedantic ANSI C.
2865 Zero means allow extended lvalues. */
2867 int pedantic_lvalues;
2869 /* When pedantic, return an expr equal to X but certainly not valid as a
2870 pedantic lvalue. Otherwise, return X. */
2873 pedantic_non_lvalue_loc (location_t loc, tree x)
2875 if (pedantic_lvalues)
2876 return non_lvalue_loc (loc, x);
2877 protected_set_expr_location (x, loc);
2881 /* Given a tree comparison code, return the code that is the logical inverse
2882 of the given code. It is not safe to do this for floating-point
2883 comparisons, except for NE_EXPR and EQ_EXPR, so we receive a machine mode
2884 as well: if reversing the comparison is unsafe, return ERROR_MARK. */
2887 invert_tree_comparison (enum tree_code code, bool honor_nans)
2889 if (honor_nans && flag_trapping_math)
2899 return honor_nans ? UNLE_EXPR : LE_EXPR;
2901 return honor_nans ? UNLT_EXPR : LT_EXPR;
2903 return honor_nans ? UNGE_EXPR : GE_EXPR;
2905 return honor_nans ? UNGT_EXPR : GT_EXPR;
2919 return UNORDERED_EXPR;
2920 case UNORDERED_EXPR:
2921 return ORDERED_EXPR;
2927 /* Similar, but return the comparison that results if the operands are
2928 swapped. This is safe for floating-point. */
2931 swap_tree_comparison (enum tree_code code)
2938 case UNORDERED_EXPR:
2964 /* Convert a comparison tree code from an enum tree_code representation
2965 into a compcode bit-based encoding. This function is the inverse of
2966 compcode_to_comparison. */
2968 static enum comparison_code
2969 comparison_to_compcode (enum tree_code code)
2986 return COMPCODE_ORD;
2987 case UNORDERED_EXPR:
2988 return COMPCODE_UNORD;
2990 return COMPCODE_UNLT;
2992 return COMPCODE_UNEQ;
2994 return COMPCODE_UNLE;
2996 return COMPCODE_UNGT;
2998 return COMPCODE_LTGT;
3000 return COMPCODE_UNGE;
3006 /* Convert a compcode bit-based encoding of a comparison operator back
3007 to GCC's enum tree_code representation. This function is the
3008 inverse of comparison_to_compcode. */
3010 static enum tree_code
3011 compcode_to_comparison (enum comparison_code code)
3028 return ORDERED_EXPR;
3029 case COMPCODE_UNORD:
3030 return UNORDERED_EXPR;
3048 /* Return a tree for the comparison which is the combination of
3049 doing the AND or OR (depending on CODE) of the two operations LCODE
3050 and RCODE on the identical operands LL_ARG and LR_ARG. Take into account
3051 the possibility of trapping if the mode has NaNs, and return NULL_TREE
3052 if this makes the transformation invalid. */
3055 combine_comparisons (location_t loc,
3056 enum tree_code code, enum tree_code lcode,
3057 enum tree_code rcode, tree truth_type,
3058 tree ll_arg, tree lr_arg)
3060 bool honor_nans = HONOR_NANS (TYPE_MODE (TREE_TYPE (ll_arg)));
3061 enum comparison_code lcompcode = comparison_to_compcode (lcode);
3062 enum comparison_code rcompcode = comparison_to_compcode (rcode);
3067 case TRUTH_AND_EXPR: case TRUTH_ANDIF_EXPR:
3068 compcode = lcompcode & rcompcode;
3071 case TRUTH_OR_EXPR: case TRUTH_ORIF_EXPR:
3072 compcode = lcompcode | rcompcode;
3081 /* Eliminate unordered comparisons, as well as LTGT and ORD
3082 which are not used unless the mode has NaNs. */
3083 compcode &= ~COMPCODE_UNORD;
3084 if (compcode == COMPCODE_LTGT)
3085 compcode = COMPCODE_NE;
3086 else if (compcode == COMPCODE_ORD)
3087 compcode = COMPCODE_TRUE;
3089 else if (flag_trapping_math)
3091 /* Check that the original operation and the optimized ones will trap
3092 under the same condition. */
3093 bool ltrap = (lcompcode & COMPCODE_UNORD) == 0
3094 && (lcompcode != COMPCODE_EQ)
3095 && (lcompcode != COMPCODE_ORD);
3096 bool rtrap = (rcompcode & COMPCODE_UNORD) == 0
3097 && (rcompcode != COMPCODE_EQ)
3098 && (rcompcode != COMPCODE_ORD);
3099 bool trap = (compcode & COMPCODE_UNORD) == 0
3100 && (compcode != COMPCODE_EQ)
3101 && (compcode != COMPCODE_ORD);
3103 /* In a short-circuited boolean expression the LHS might be
3104 such that the RHS, if evaluated, will never trap. For
3105 example, in ORD (x, y) && (x < y), we evaluate the RHS only
3106 if neither x nor y is NaN. (This is a mixed blessing: for
3107 example, the expression above will never trap, hence
3108 optimizing it to x < y would be invalid). */
3109 if ((code == TRUTH_ORIF_EXPR && (lcompcode & COMPCODE_UNORD))
3110 || (code == TRUTH_ANDIF_EXPR && !(lcompcode & COMPCODE_UNORD)))
3113 /* If the comparison was short-circuited, and only the RHS
3114 trapped, we may now generate a spurious trap. */
3116 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3119 /* If we changed the conditions that cause a trap, we lose. */
3120 if ((ltrap || rtrap) != trap)
3124 if (compcode == COMPCODE_TRUE)
3125 return constant_boolean_node (true, truth_type);
3126 else if (compcode == COMPCODE_FALSE)
3127 return constant_boolean_node (false, truth_type);
3130 enum tree_code tcode;
3132 tcode = compcode_to_comparison ((enum comparison_code) compcode);
3133 return fold_build2_loc (loc, tcode, truth_type, ll_arg, lr_arg);
3137 /* Return nonzero if two operands (typically of the same tree node)
3138 are necessarily equal. If either argument has side-effects this
3139 function returns zero. FLAGS modifies behavior as follows:
3141 If OEP_ONLY_CONST is set, only return nonzero for constants.
3142 This function tests whether the operands are indistinguishable;
3143 it does not test whether they are equal using C's == operation.
3144 The distinction is important for IEEE floating point, because
3145 (1) -0.0 and 0.0 are distinguishable, but -0.0==0.0, and
3146 (2) two NaNs may be indistinguishable, but NaN!=NaN.
3148 If OEP_ONLY_CONST is unset, a VAR_DECL is considered equal to itself
3149 even though it may hold multiple values during a function.
3150 This is because a GCC tree node guarantees that nothing else is
3151 executed between the evaluation of its "operands" (which may often
3152 be evaluated in arbitrary order). Hence if the operands themselves
3153 don't side-effect, the VAR_DECLs, PARM_DECLs etc... must hold the
3154 same value in each operand/subexpression. Hence leaving OEP_ONLY_CONST
3155 unset means assuming isochronic (or instantaneous) tree equivalence.
3156 Unless comparing arbitrary expression trees, such as from different
3157 statements, this flag can usually be left unset.
3159 If OEP_PURE_SAME is set, then pure functions with identical arguments
3160 are considered the same. It is used when the caller has other ways
3161 to ensure that global memory is unchanged in between. */
3164 operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
3166 /* If either is ERROR_MARK, they aren't equal. */
3167 if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK)
3170 /* Check equality of integer constants before bailing out due to
3171 precision differences. */
3172 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
3173 return tree_int_cst_equal (arg0, arg1);
3175 /* If both types don't have the same signedness, then we can't consider
3176 them equal. We must check this before the STRIP_NOPS calls
3177 because they may change the signedness of the arguments. As pointers
3178 strictly don't have a signedness, require either two pointers or
3179 two non-pointers as well. */
3180 if (TYPE_UNSIGNED (TREE_TYPE (arg0)) != TYPE_UNSIGNED (TREE_TYPE (arg1))
3181 || POINTER_TYPE_P (TREE_TYPE (arg0)) != POINTER_TYPE_P (TREE_TYPE (arg1)))
3184 /* We cannot consider pointers to different address space equal. */
3185 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && POINTER_TYPE_P (TREE_TYPE (arg1))
3186 && (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg0)))
3187 != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (arg1)))))
3190 /* If both types don't have the same precision, then it is not safe
3192 if (TYPE_PRECISION (TREE_TYPE (arg0)) != TYPE_PRECISION (TREE_TYPE (arg1)))
3198 /* In case both args are comparisons but with different comparison
3199 code, try to swap the comparison operands of one arg to produce
3200 a match and compare that variant. */
3201 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3202 && COMPARISON_CLASS_P (arg0)
3203 && COMPARISON_CLASS_P (arg1))
3205 enum tree_code swap_code = swap_tree_comparison (TREE_CODE (arg1));
3207 if (TREE_CODE (arg0) == swap_code)
3208 return operand_equal_p (TREE_OPERAND (arg0, 0),
3209 TREE_OPERAND (arg1, 1), flags)
3210 && operand_equal_p (TREE_OPERAND (arg0, 1),
3211 TREE_OPERAND (arg1, 0), flags);
3214 if (TREE_CODE (arg0) != TREE_CODE (arg1)
3215 /* This is needed for conversions and for COMPONENT_REF.
3216 Might as well play it safe and always test this. */
3217 || TREE_CODE (TREE_TYPE (arg0)) == ERROR_MARK
3218 || TREE_CODE (TREE_TYPE (arg1)) == ERROR_MARK
3219 || TYPE_MODE (TREE_TYPE (arg0)) != TYPE_MODE (TREE_TYPE (arg1)))
3222 /* If ARG0 and ARG1 are the same SAVE_EXPR, they are necessarily equal.
3223 We don't care about side effects in that case because the SAVE_EXPR
3224 takes care of that for us. In all other cases, two expressions are
3225 equal if they have no side effects. If we have two identical
3226 expressions with side effects that should be treated the same due
3227 to the only side effects being identical SAVE_EXPR's, that will
3228 be detected in the recursive calls below. */
3229 if (arg0 == arg1 && ! (flags & OEP_ONLY_CONST)
3230 && (TREE_CODE (arg0) == SAVE_EXPR
3231 || (! TREE_SIDE_EFFECTS (arg0) && ! TREE_SIDE_EFFECTS (arg1))))
3234 /* Next handle constant cases, those for which we can return 1 even
3235 if ONLY_CONST is set. */
3236 if (TREE_CONSTANT (arg0) && TREE_CONSTANT (arg1))
3237 switch (TREE_CODE (arg0))
3240 return tree_int_cst_equal (arg0, arg1);
3243 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (arg0),
3244 TREE_FIXED_CST (arg1));
3247 if (REAL_VALUES_IDENTICAL (TREE_REAL_CST (arg0),
3248 TREE_REAL_CST (arg1)))
3252 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0))))
3254 /* If we do not distinguish between signed and unsigned zero,
3255 consider them equal. */
3256 if (real_zerop (arg0) && real_zerop (arg1))
3265 v1 = TREE_VECTOR_CST_ELTS (arg0);
3266 v2 = TREE_VECTOR_CST_ELTS (arg1);
3269 if (!operand_equal_p (TREE_VALUE (v1), TREE_VALUE (v2),
3272 v1 = TREE_CHAIN (v1);
3273 v2 = TREE_CHAIN (v2);
3280 return (operand_equal_p (TREE_REALPART (arg0), TREE_REALPART (arg1),
3282 && operand_equal_p (TREE_IMAGPART (arg0), TREE_IMAGPART (arg1),
3286 return (TREE_STRING_LENGTH (arg0) == TREE_STRING_LENGTH (arg1)
3287 && ! memcmp (TREE_STRING_POINTER (arg0),
3288 TREE_STRING_POINTER (arg1),
3289 TREE_STRING_LENGTH (arg0)));
3292 return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0),
3298 if (flags & OEP_ONLY_CONST)
3301 /* Define macros to test an operand from arg0 and arg1 for equality and a
3302 variant that allows null and views null as being different from any
3303 non-null value. In the latter case, if either is null, the both
3304 must be; otherwise, do the normal comparison. */
3305 #define OP_SAME(N) operand_equal_p (TREE_OPERAND (arg0, N), \
3306 TREE_OPERAND (arg1, N), flags)
3308 #define OP_SAME_WITH_NULL(N) \
3309 ((!TREE_OPERAND (arg0, N) || !TREE_OPERAND (arg1, N)) \
3310 ? TREE_OPERAND (arg0, N) == TREE_OPERAND (arg1, N) : OP_SAME (N))
3312 switch (TREE_CODE_CLASS (TREE_CODE (arg0)))
3315 /* Two conversions are equal only if signedness and modes match. */
3316 switch (TREE_CODE (arg0))
3319 case FIX_TRUNC_EXPR:
3320 if (TYPE_UNSIGNED (TREE_TYPE (arg0))
3321 != TYPE_UNSIGNED (TREE_TYPE (arg1)))
3331 case tcc_comparison:
3333 if (OP_SAME (0) && OP_SAME (1))
3336 /* For commutative ops, allow the other order. */
3337 return (commutative_tree_code (TREE_CODE (arg0))
3338 && operand_equal_p (TREE_OPERAND (arg0, 0),
3339 TREE_OPERAND (arg1, 1), flags)
3340 && operand_equal_p (TREE_OPERAND (arg0, 1),
3341 TREE_OPERAND (arg1, 0), flags));
3344 /* If either of the pointer (or reference) expressions we are
3345 dereferencing contain a side effect, these cannot be equal. */
3346 if (TREE_SIDE_EFFECTS (arg0)
3347 || TREE_SIDE_EFFECTS (arg1))
3350 switch (TREE_CODE (arg0))
3353 case ALIGN_INDIRECT_REF:
3354 case MISALIGNED_INDIRECT_REF:
3360 case ARRAY_RANGE_REF:
3361 /* Operands 2 and 3 may be null.
3362 Compare the array index by value if it is constant first as we
3363 may have different types but same value here. */
3365 && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
3366 TREE_OPERAND (arg1, 1))
3368 && OP_SAME_WITH_NULL (2)
3369 && OP_SAME_WITH_NULL (3));
3372 /* Handle operand 2 the same as for ARRAY_REF. Operand 0
3373 may be NULL when we're called to compare MEM_EXPRs. */
3374 return OP_SAME_WITH_NULL (0)
3376 && OP_SAME_WITH_NULL (2);
3379 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3385 case tcc_expression:
3386 switch (TREE_CODE (arg0))
3389 case TRUTH_NOT_EXPR:
3392 case TRUTH_ANDIF_EXPR:
3393 case TRUTH_ORIF_EXPR:
3394 return OP_SAME (0) && OP_SAME (1);
3396 case TRUTH_AND_EXPR:
3398 case TRUTH_XOR_EXPR:
3399 if (OP_SAME (0) && OP_SAME (1))
3402 /* Otherwise take into account this is a commutative operation. */
3403 return (operand_equal_p (TREE_OPERAND (arg0, 0),
3404 TREE_OPERAND (arg1, 1), flags)
3405 && operand_equal_p (TREE_OPERAND (arg0, 1),
3406 TREE_OPERAND (arg1, 0), flags));
3409 return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
3416 switch (TREE_CODE (arg0))
3419 /* If the CALL_EXPRs call different functions, then they
3420 clearly can not be equal. */
3421 if (! operand_equal_p (CALL_EXPR_FN (arg0), CALL_EXPR_FN (arg1),
3426 unsigned int cef = call_expr_flags (arg0);
3427 if (flags & OEP_PURE_SAME)
3428 cef &= ECF_CONST | ECF_PURE;
3435 /* Now see if all the arguments are the same. */
3437 const_call_expr_arg_iterator iter0, iter1;
3439 for (a0 = first_const_call_expr_arg (arg0, &iter0),
3440 a1 = first_const_call_expr_arg (arg1, &iter1);
3442 a0 = next_const_call_expr_arg (&iter0),
3443 a1 = next_const_call_expr_arg (&iter1))
3444 if (! operand_equal_p (a0, a1, flags))
3447 /* If we get here and both argument lists are exhausted
3448 then the CALL_EXPRs are equal. */
3449 return ! (a0 || a1);
3455 case tcc_declaration:
3456 /* Consider __builtin_sqrt equal to sqrt. */
3457 return (TREE_CODE (arg0) == FUNCTION_DECL
3458 && DECL_BUILT_IN (arg0) && DECL_BUILT_IN (arg1)
3459 && DECL_BUILT_IN_CLASS (arg0) == DECL_BUILT_IN_CLASS (arg1)
3460 && DECL_FUNCTION_CODE (arg0) == DECL_FUNCTION_CODE (arg1));
3467 #undef OP_SAME_WITH_NULL
3470 /* Similar to operand_equal_p, but see if ARG0 might have been made by
3471 shorten_compare from ARG1 when ARG1 was being compared with OTHER.
3473 When in doubt, return 0. */
3476 operand_equal_for_comparison_p (tree arg0, tree arg1, tree other)
3478 int unsignedp1, unsignedpo;
3479 tree primarg0, primarg1, primother;
3480 unsigned int correct_width;
3482 if (operand_equal_p (arg0, arg1, 0))
3485 if (! INTEGRAL_TYPE_P (TREE_TYPE (arg0))
3486 || ! INTEGRAL_TYPE_P (TREE_TYPE (arg1)))
3489 /* Discard any conversions that don't change the modes of ARG0 and ARG1
3490 and see if the inner values are the same. This removes any
3491 signedness comparison, which doesn't matter here. */
3492 primarg0 = arg0, primarg1 = arg1;
3493 STRIP_NOPS (primarg0);
3494 STRIP_NOPS (primarg1);
3495 if (operand_equal_p (primarg0, primarg1, 0))
3498 /* Duplicate what shorten_compare does to ARG1 and see if that gives the
3499 actual comparison operand, ARG0.
3501 First throw away any conversions to wider types
3502 already present in the operands. */
3504 primarg1 = get_narrower (arg1, &unsignedp1);
3505 primother = get_narrower (other, &unsignedpo);
3507 correct_width = TYPE_PRECISION (TREE_TYPE (arg1));
3508 if (unsignedp1 == unsignedpo
3509 && TYPE_PRECISION (TREE_TYPE (primarg1)) < correct_width
3510 && TYPE_PRECISION (TREE_TYPE (primother)) < correct_width)
3512 tree type = TREE_TYPE (arg0);
3514 /* Make sure shorter operand is extended the right way
3515 to match the longer operand. */
3516 primarg1 = fold_convert (signed_or_unsigned_type_for
3517 (unsignedp1, TREE_TYPE (primarg1)), primarg1);
3519 if (operand_equal_p (arg0, fold_convert (type, primarg1), 0))
3526 /* See if ARG is an expression that is either a comparison or is performing
3527 arithmetic on comparisons. The comparisons must only be comparing
3528 two different values, which will be stored in *CVAL1 and *CVAL2; if
3529 they are nonzero it means that some operands have already been found.
3530 No variables may be used anywhere else in the expression except in the
3531 comparisons. If SAVE_P is true it means we removed a SAVE_EXPR around
3532 the expression and save_expr needs to be called with CVAL1 and CVAL2.
3534 If this is true, return 1. Otherwise, return zero. */
3537 twoval_comparison_p (tree arg, tree *cval1, tree *cval2, int *save_p)
3539 enum tree_code code = TREE_CODE (arg);
3540 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3542 /* We can handle some of the tcc_expression cases here. */
3543 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3545 else if (tclass == tcc_expression
3546 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR
3547 || code == COMPOUND_EXPR))
3548 tclass = tcc_binary;
3550 else if (tclass == tcc_expression && code == SAVE_EXPR
3551 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
3553 /* If we've already found a CVAL1 or CVAL2, this expression is
3554 two complex to handle. */
3555 if (*cval1 || *cval2)
3565 return twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p);
3568 return (twoval_comparison_p (TREE_OPERAND (arg, 0), cval1, cval2, save_p)
3569 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3570 cval1, cval2, save_p));
3575 case tcc_expression:
3576 if (code == COND_EXPR)
3577 return (twoval_comparison_p (TREE_OPERAND (arg, 0),
3578 cval1, cval2, save_p)
3579 && twoval_comparison_p (TREE_OPERAND (arg, 1),
3580 cval1, cval2, save_p)
3581 && twoval_comparison_p (TREE_OPERAND (arg, 2),
3582 cval1, cval2, save_p));
3585 case tcc_comparison:
3586 /* First see if we can handle the first operand, then the second. For
3587 the second operand, we know *CVAL1 can't be zero. It must be that
3588 one side of the comparison is each of the values; test for the
3589 case where this isn't true by failing if the two operands
3592 if (operand_equal_p (TREE_OPERAND (arg, 0),
3593 TREE_OPERAND (arg, 1), 0))
3597 *cval1 = TREE_OPERAND (arg, 0);
3598 else if (operand_equal_p (*cval1, TREE_OPERAND (arg, 0), 0))
3600 else if (*cval2 == 0)
3601 *cval2 = TREE_OPERAND (arg, 0);
3602 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 0), 0))
3607 if (operand_equal_p (*cval1, TREE_OPERAND (arg, 1), 0))
3609 else if (*cval2 == 0)
3610 *cval2 = TREE_OPERAND (arg, 1);
3611 else if (operand_equal_p (*cval2, TREE_OPERAND (arg, 1), 0))
3623 /* ARG is a tree that is known to contain just arithmetic operations and
3624 comparisons. Evaluate the operations in the tree substituting NEW0 for
3625 any occurrence of OLD0 as an operand of a comparison and likewise for
3629 eval_subst (location_t loc, tree arg, tree old0, tree new0,
3630 tree old1, tree new1)
3632 tree type = TREE_TYPE (arg);
3633 enum tree_code code = TREE_CODE (arg);
3634 enum tree_code_class tclass = TREE_CODE_CLASS (code);
3636 /* We can handle some of the tcc_expression cases here. */
3637 if (tclass == tcc_expression && code == TRUTH_NOT_EXPR)
3639 else if (tclass == tcc_expression
3640 && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR))
3641 tclass = tcc_binary;
3646 return fold_build1_loc (loc, code, type,
3647 eval_subst (loc, TREE_OPERAND (arg, 0),
3648 old0, new0, old1, new1));
3651 return fold_build2_loc (loc, code, type,
3652 eval_subst (loc, TREE_OPERAND (arg, 0),
3653 old0, new0, old1, new1),
3654 eval_subst (loc, TREE_OPERAND (arg, 1),
3655 old0, new0, old1, new1));
3657 case tcc_expression:
3661 return eval_subst (loc, TREE_OPERAND (arg, 0), old0, new0,
3665 return eval_subst (loc, TREE_OPERAND (arg, 1), old0, new0,
3669 return fold_build3_loc (loc, code, type,
3670 eval_subst (loc, TREE_OPERAND (arg, 0),
3671 old0, new0, old1, new1),
3672 eval_subst (loc, TREE_OPERAND (arg, 1),
3673 old0, new0, old1, new1),
3674 eval_subst (loc, TREE_OPERAND (arg, 2),
3675 old0, new0, old1, new1));
3679 /* Fall through - ??? */
3681 case tcc_comparison:
3683 tree arg0 = TREE_OPERAND (arg, 0);
3684 tree arg1 = TREE_OPERAND (arg, 1);
3686 /* We need to check both for exact equality and tree equality. The
3687 former will be true if the operand has a side-effect. In that
3688 case, we know the operand occurred exactly once. */
3690 if (arg0 == old0 || operand_equal_p (arg0, old0, 0))
3692 else if (arg0 == old1 || operand_equal_p (arg0, old1, 0))
3695 if (arg1 == old0 || operand_equal_p (arg1, old0, 0))
3697 else if (arg1 == old1 || operand_equal_p (arg1, old1, 0))
3700 return fold_build2_loc (loc, code, type, arg0, arg1);
3708 /* Return a tree for the case when the result of an expression is RESULT
3709 converted to TYPE and OMITTED was previously an operand of the expression
3710 but is now not needed (e.g., we folded OMITTED * 0).
3712 If OMITTED has side effects, we must evaluate it. Otherwise, just do
3713 the conversion of RESULT to TYPE. */
3716 omit_one_operand_loc (location_t loc, tree type, tree result, tree omitted)
3718 tree t = fold_convert_loc (loc, type, result);
3720 /* If the resulting operand is an empty statement, just return the omitted
3721 statement casted to void. */
3722 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3724 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3725 goto omit_one_operand_exit;
3728 if (TREE_SIDE_EFFECTS (omitted))
3730 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3731 goto omit_one_operand_exit;
3734 return non_lvalue_loc (loc, t);
3736 omit_one_operand_exit:
3737 protected_set_expr_location (t, loc);
3741 /* Similar, but call pedantic_non_lvalue instead of non_lvalue. */
3744 pedantic_omit_one_operand_loc (location_t loc, tree type, tree result,
3747 tree t = fold_convert_loc (loc, type, result);
3749 /* If the resulting operand is an empty statement, just return the omitted
3750 statement casted to void. */
3751 if (IS_EMPTY_STMT (t) && TREE_SIDE_EFFECTS (omitted))
3753 t = build1 (NOP_EXPR, void_type_node, fold_ignored_result (omitted));
3754 goto pedantic_omit_one_operand_exit;
3757 if (TREE_SIDE_EFFECTS (omitted))
3759 t = build2 (COMPOUND_EXPR, type, fold_ignored_result (omitted), t);
3760 goto pedantic_omit_one_operand_exit;
3763 return pedantic_non_lvalue_loc (loc, t);
3765 pedantic_omit_one_operand_exit:
3766 protected_set_expr_location (t, loc);
3770 /* Return a tree for the case when the result of an expression is RESULT
3771 converted to TYPE and OMITTED1 and OMITTED2 were previously operands
3772 of the expression but are now not needed.
3774 If OMITTED1 or OMITTED2 has side effects, they must be evaluated.
3775 If both OMITTED1 and OMITTED2 have side effects, OMITTED1 is
3776 evaluated before OMITTED2. Otherwise, if neither has side effects,
3777 just do the conversion of RESULT to TYPE. */
3780 omit_two_operands_loc (location_t loc, tree type, tree result,
3781 tree omitted1, tree omitted2)
3783 tree t = fold_convert_loc (loc, type, result);
3785 if (TREE_SIDE_EFFECTS (omitted2))
3787 t = build2 (COMPOUND_EXPR, type, omitted2, t);
3788 SET_EXPR_LOCATION (t, loc);
3790 if (TREE_SIDE_EFFECTS (omitted1))
3792 t = build2 (COMPOUND_EXPR, type, omitted1, t);
3793 SET_EXPR_LOCATION (t, loc);
3796 return TREE_CODE (t) != COMPOUND_EXPR ? non_lvalue_loc (loc, t) : t;
3800 /* Return a simplified tree node for the truth-negation of ARG. This
3801 never alters ARG itself. We assume that ARG is an operation that
3802 returns a truth value (0 or 1).
3804 FIXME: one would think we would fold the result, but it causes
3805 problems with the dominator optimizer. */
3808 fold_truth_not_expr (location_t loc, tree arg)
3810 tree t, type = TREE_TYPE (arg);
3811 enum tree_code code = TREE_CODE (arg);
3812 location_t loc1, loc2;
3814 /* If this is a comparison, we can simply invert it, except for
3815 floating-point non-equality comparisons, in which case we just
3816 enclose a TRUTH_NOT_EXPR around what we have. */
3818 if (TREE_CODE_CLASS (code) == tcc_comparison)
3820 tree op_type = TREE_TYPE (TREE_OPERAND (arg, 0));
3821 if (FLOAT_TYPE_P (op_type)
3822 && flag_trapping_math
3823 && code != ORDERED_EXPR && code != UNORDERED_EXPR
3824 && code != NE_EXPR && code != EQ_EXPR)
3827 code = invert_tree_comparison (code, HONOR_NANS (TYPE_MODE (op_type)));
3828 if (code == ERROR_MARK)
3831 t = build2 (code, type, TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1));
3832 SET_EXPR_LOCATION (t, loc);
3839 return constant_boolean_node (integer_zerop (arg), type);
3841 case TRUTH_AND_EXPR:
3842 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3843 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3844 if (loc1 == UNKNOWN_LOCATION)
3846 if (loc2 == UNKNOWN_LOCATION)
3848 t = build2 (TRUTH_OR_EXPR, type,
3849 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3850 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3854 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3855 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3856 if (loc1 == UNKNOWN_LOCATION)
3858 if (loc2 == UNKNOWN_LOCATION)
3860 t = build2 (TRUTH_AND_EXPR, type,
3861 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3862 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3865 case TRUTH_XOR_EXPR:
3866 /* Here we can invert either operand. We invert the first operand
3867 unless the second operand is a TRUTH_NOT_EXPR in which case our
3868 result is the XOR of the first operand with the inside of the
3869 negation of the second operand. */
3871 if (TREE_CODE (TREE_OPERAND (arg, 1)) == TRUTH_NOT_EXPR)
3872 t = build2 (TRUTH_XOR_EXPR, type, TREE_OPERAND (arg, 0),
3873 TREE_OPERAND (TREE_OPERAND (arg, 1), 0));
3875 t = build2 (TRUTH_XOR_EXPR, type,
3876 invert_truthvalue_loc (loc, TREE_OPERAND (arg, 0)),
3877 TREE_OPERAND (arg, 1));
3880 case TRUTH_ANDIF_EXPR:
3881 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3882 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3883 if (loc1 == UNKNOWN_LOCATION)
3885 if (loc2 == UNKNOWN_LOCATION)
3887 t = build2 (TRUTH_ORIF_EXPR, type,
3888 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3889 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3892 case TRUTH_ORIF_EXPR:
3893 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3894 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3895 if (loc1 == UNKNOWN_LOCATION)
3897 if (loc2 == UNKNOWN_LOCATION)
3899 t = build2 (TRUTH_ANDIF_EXPR, type,
3900 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)),
3901 invert_truthvalue_loc (loc2, TREE_OPERAND (arg, 1)));
3904 case TRUTH_NOT_EXPR:
3905 return TREE_OPERAND (arg, 0);
3909 tree arg1 = TREE_OPERAND (arg, 1);
3910 tree arg2 = TREE_OPERAND (arg, 2);
3912 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3913 loc2 = EXPR_LOCATION (TREE_OPERAND (arg, 2));
3914 if (loc1 == UNKNOWN_LOCATION)
3916 if (loc2 == UNKNOWN_LOCATION)
3919 /* A COND_EXPR may have a throw as one operand, which
3920 then has void type. Just leave void operands
3922 t = build3 (COND_EXPR, type, TREE_OPERAND (arg, 0),
3923 VOID_TYPE_P (TREE_TYPE (arg1))
3924 ? arg1 : invert_truthvalue_loc (loc1, arg1),
3925 VOID_TYPE_P (TREE_TYPE (arg2))
3926 ? arg2 : invert_truthvalue_loc (loc2, arg2));
3931 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 1));
3932 if (loc1 == UNKNOWN_LOCATION)
3934 t = build2 (COMPOUND_EXPR, type,
3935 TREE_OPERAND (arg, 0),
3936 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 1)));
3939 case NON_LVALUE_EXPR:
3940 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3941 if (loc1 == UNKNOWN_LOCATION)
3943 return invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0));
3946 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3948 t = build1 (TRUTH_NOT_EXPR, type, arg);
3952 /* ... fall through ... */
3955 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3956 if (loc1 == UNKNOWN_LOCATION)
3958 t = build1 (TREE_CODE (arg), type,
3959 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3963 if (!integer_onep (TREE_OPERAND (arg, 1)))
3965 t = build2 (EQ_EXPR, type, arg, build_int_cst (type, 0));
3969 t = build1 (TRUTH_NOT_EXPR, type, arg);
3972 case CLEANUP_POINT_EXPR:
3973 loc1 = EXPR_LOCATION (TREE_OPERAND (arg, 0));
3974 if (loc1 == UNKNOWN_LOCATION)
3976 t = build1 (CLEANUP_POINT_EXPR, type,
3977 invert_truthvalue_loc (loc1, TREE_OPERAND (arg, 0)));
3986 SET_EXPR_LOCATION (t, loc);
3991 /* Return a simplified tree node for the truth-negation of ARG. This
3992 never alters ARG itself. We assume that ARG is an operation that
3993 returns a truth value (0 or 1).
3995 FIXME: one would think we would fold the result, but it causes
3996 problems with the dominator optimizer. */
3999 invert_truthvalue_loc (location_t loc, tree arg)
4003 if (TREE_CODE (arg) == ERROR_MARK)
4006 tem = fold_truth_not_expr (loc, arg);
4009 tem = build1 (TRUTH_NOT_EXPR, TREE_TYPE (arg), arg);
4010 SET_EXPR_LOCATION (tem, loc);
4016 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
4017 operands are another bit-wise operation with a common input. If so,
4018 distribute the bit operations to save an operation and possibly two if
4019 constants are involved. For example, convert
4020 (A | B) & (A | C) into A | (B & C)
4021 Further simplification will occur if B and C are constants.
4023 If this optimization cannot be done, 0 will be returned. */
4026 distribute_bit_expr (location_t loc, enum tree_code code, tree type,
4027 tree arg0, tree arg1)
4032 if (TREE_CODE (arg0) != TREE_CODE (arg1)
4033 || TREE_CODE (arg0) == code
4034 || (TREE_CODE (arg0) != BIT_AND_EXPR
4035 && TREE_CODE (arg0) != BIT_IOR_EXPR))
4038 if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), 0))
4040 common = TREE_OPERAND (arg0, 0);
4041 left = TREE_OPERAND (arg0, 1);
4042 right = TREE_OPERAND (arg1, 1);
4044 else if (operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 1), 0))
4046 common = TREE_OPERAND (arg0, 0);
4047 left = TREE_OPERAND (arg0, 1);
4048 right = TREE_OPERAND (arg1, 0);
4050 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 0), 0))
4052 common = TREE_OPERAND (arg0, 1);
4053 left = TREE_OPERAND (arg0, 0);
4054 right = TREE_OPERAND (arg1, 1);
4056 else if (operand_equal_p (TREE_OPERAND (arg0, 1), TREE_OPERAND (arg1, 1), 0))
4058 common = TREE_OPERAND (arg0, 1);
4059 left = TREE_OPERAND (arg0, 0);
4060 right = TREE_OPERAND (arg1, 0);
4065 common = fold_convert_loc (loc, type, common);
4066 left = fold_convert_loc (loc, type, left);
4067 right = fold_convert_loc (loc, type, right);
4068 return fold_build2_loc (loc, TREE_CODE (arg0), type, common,
4069 fold_build2_loc (loc, code, type, left, right));
4072 /* Knowing that ARG0 and ARG1 are both RDIV_EXPRs, simplify a binary operation
4073 with code CODE. This optimization is unsafe. */
4075 distribute_real_division (location_t loc, enum tree_code code, tree type,
4076 tree arg0, tree arg1)
4078 bool mul0 = TREE_CODE (arg0) == MULT_EXPR;
4079 bool mul1 = TREE_CODE (arg1) == MULT_EXPR;
4081 /* (A / C) +- (B / C) -> (A +- B) / C. */
4083 && operand_equal_p (TREE_OPERAND (arg0, 1),
4084 TREE_OPERAND (arg1, 1), 0))
4085 return fold_build2_loc (loc, mul0 ? MULT_EXPR : RDIV_EXPR, type,
4086 fold_build2_loc (loc, code, type,
4087 TREE_OPERAND (arg0, 0),
4088 TREE_OPERAND (arg1, 0)),
4089 TREE_OPERAND (arg0, 1));
4091 /* (A / C1) +- (A / C2) -> A * (1 / C1 +- 1 / C2). */
4092 if (operand_equal_p (TREE_OPERAND (arg0, 0),
4093 TREE_OPERAND (arg1, 0), 0)
4094 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
4095 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
4097 REAL_VALUE_TYPE r0, r1;
4098 r0 = TREE_REAL_CST (TREE_OPERAND (arg0, 1));
4099 r1 = TREE_REAL_CST (TREE_OPERAND (arg1, 1));
4101 real_arithmetic (&r0, RDIV_EXPR, &dconst1, &r0);
4103 real_arithmetic (&r1, RDIV_EXPR, &dconst1, &r1);
4104 real_arithmetic (&r0, code, &r0, &r1);
4105 return fold_build2_loc (loc, MULT_EXPR, type,
4106 TREE_OPERAND (arg0, 0),
4107 build_real (type, r0));
4113 /* Return a BIT_FIELD_REF of type TYPE to refer to BITSIZE bits of INNER
4114 starting at BITPOS. The field is unsigned if UNSIGNEDP is nonzero. */
4117 make_bit_field_ref (location_t loc, tree inner, tree type,
4118 HOST_WIDE_INT bitsize, HOST_WIDE_INT bitpos, int unsignedp)
4120 tree result, bftype;
4124 tree size = TYPE_SIZE (TREE_TYPE (inner));
4125 if ((INTEGRAL_TYPE_P (TREE_TYPE (inner))
4126 || POINTER_TYPE_P (TREE_TYPE (inner)))
4127 && host_integerp (size, 0)
4128 && tree_low_cst (size, 0) == bitsize)
4129 return fold_convert_loc (loc, type, inner);
4133 if (TYPE_PRECISION (bftype) != bitsize
4134 || TYPE_UNSIGNED (bftype) == !unsignedp)
4135 bftype = build_nonstandard_integer_type (bitsize, 0);
4137 result = build3 (BIT_FIELD_REF, bftype, inner,
4138 size_int (bitsize), bitsize_int (bitpos));
4139 SET_EXPR_LOCATION (result, loc);
4142 result = fold_convert_loc (loc, type, result);
4147 /* Optimize a bit-field compare.
4149 There are two cases: First is a compare against a constant and the
4150 second is a comparison of two items where the fields are at the same
4151 bit position relative to the start of a chunk (byte, halfword, word)
4152 large enough to contain it. In these cases we can avoid the shift
4153 implicit in bitfield extractions.
4155 For constants, we emit a compare of the shifted constant with the
4156 BIT_AND_EXPR of a mask and a byte, halfword, or word of the operand being
4157 compared. For two fields at the same position, we do the ANDs with the
4158 similar mask and compare the result of the ANDs.
4160 CODE is the comparison code, known to be either NE_EXPR or EQ_EXPR.
4161 COMPARE_TYPE is the type of the comparison, and LHS and RHS
4162 are the left and right operands of the comparison, respectively.
4164 If the optimization described above can be done, we return the resulting
4165 tree. Otherwise we return zero. */
4168 optimize_bit_field_compare (location_t loc, enum tree_code code,
4169 tree compare_type, tree lhs, tree rhs)
4171 HOST_WIDE_INT lbitpos, lbitsize, rbitpos, rbitsize, nbitpos, nbitsize;
4172 tree type = TREE_TYPE (lhs);
4173 tree signed_type, unsigned_type;
4174 int const_p = TREE_CODE (rhs) == INTEGER_CST;
4175 enum machine_mode lmode, rmode, nmode;
4176 int lunsignedp, runsignedp;
4177 int lvolatilep = 0, rvolatilep = 0;
4178 tree linner, rinner = NULL_TREE;
4182 /* Get all the information about the extractions being done. If the bit size
4183 if the same as the size of the underlying object, we aren't doing an
4184 extraction at all and so can do nothing. We also don't want to
4185 do anything if the inner expression is a PLACEHOLDER_EXPR since we
4186 then will no longer be able to replace it. */
4187 linner = get_inner_reference (lhs, &lbitsize, &lbitpos, &offset, &lmode,
4188 &lunsignedp, &lvolatilep, false);
4189 if (linner == lhs || lbitsize == GET_MODE_BITSIZE (lmode) || lbitsize < 0
4190 || offset != 0 || TREE_CODE (linner) == PLACEHOLDER_EXPR)
4195 /* If this is not a constant, we can only do something if bit positions,
4196 sizes, and signedness are the same. */
4197 rinner = get_inner_reference (rhs, &rbitsize, &rbitpos, &offset, &rmode,
4198 &runsignedp, &rvolatilep, false);
4200 if (rinner == rhs || lbitpos != rbitpos || lbitsize != rbitsize
4201 || lunsignedp != runsignedp || offset != 0
4202 || TREE_CODE (rinner) == PLACEHOLDER_EXPR)
4206 /* See if we can find a mode to refer to this field. We should be able to,
4207 but fail if we can't. */
4208 nmode = get_best_mode (lbitsize, lbitpos,
4209 const_p ? TYPE_ALIGN (TREE_TYPE (linner))
4210 : MIN (TYPE_ALIGN (TREE_TYPE (linner)),
4211 TYPE_ALIGN (TREE_TYPE (rinner))),
4212 word_mode, lvolatilep || rvolatilep);
4213 if (nmode == VOIDmode)
4216 /* Set signed and unsigned types of the precision of this mode for the
4218 signed_type = lang_hooks.types.type_for_mode (nmode, 0);
4219 unsigned_type = lang_hooks.types.type_for_mode (nmode, 1);
4221 /* Compute the bit position and size for the new reference and our offset
4222 within it. If the new reference is the same size as the original, we
4223 won't optimize anything, so return zero. */
4224 nbitsize = GET_MODE_BITSIZE (nmode);
4225 nbitpos = lbitpos & ~ (nbitsize - 1);
4227 if (nbitsize == lbitsize)
4230 if (BYTES_BIG_ENDIAN)
4231 lbitpos = nbitsize - lbitsize - lbitpos;
4233 /* Make the mask to be used against the extracted field. */
4234 mask = build_int_cst_type (unsigned_type, -1);
4235 mask = const_binop (LSHIFT_EXPR, mask, size_int (nbitsize - lbitsize), 0);
4236 mask = const_binop (RSHIFT_EXPR, mask,
4237 size_int (nbitsize - lbitsize - lbitpos), 0);
4240 /* If not comparing with constant, just rework the comparison
4242 return fold_build2_loc (loc, code, compare_type,
4243 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4244 make_bit_field_ref (loc, linner,
4249 fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4250 make_bit_field_ref (loc, rinner,
4256 /* Otherwise, we are handling the constant case. See if the constant is too
4257 big for the field. Warn and return a tree of for 0 (false) if so. We do
4258 this not only for its own sake, but to avoid having to test for this
4259 error case below. If we didn't, we might generate wrong code.
4261 For unsigned fields, the constant shifted right by the field length should
4262 be all zero. For signed fields, the high-order bits should agree with
4267 if (! integer_zerop (const_binop (RSHIFT_EXPR,
4268 fold_convert_loc (loc,
4269 unsigned_type, rhs),
4270 size_int (lbitsize), 0)))
4272 warning (0, "comparison is always %d due to width of bit-field",
4274 return constant_boolean_node (code == NE_EXPR, compare_type);
4279 tree tem = const_binop (RSHIFT_EXPR,
4280 fold_convert_loc (loc, signed_type, rhs),
4281 size_int (lbitsize - 1), 0);
4282 if (! integer_zerop (tem) && ! integer_all_onesp (tem))
4284 warning (0, "comparison is always %d due to width of bit-field",
4286 return constant_boolean_node (code == NE_EXPR, compare_type);
4290 /* Single-bit compares should always be against zero. */
4291 if (lbitsize == 1 && ! integer_zerop (rhs))
4293 code = code == EQ_EXPR ? NE_EXPR : EQ_EXPR;
4294 rhs = build_int_cst (type, 0);
4297 /* Make a new bitfield reference, shift the constant over the
4298 appropriate number of bits and mask it with the computed mask
4299 (in case this was a signed field). If we changed it, make a new one. */
4300 lhs = make_bit_field_ref (loc, linner, unsigned_type, nbitsize, nbitpos, 1);
4303 TREE_SIDE_EFFECTS (lhs) = 1;
4304 TREE_THIS_VOLATILE (lhs) = 1;
4307 rhs = const_binop (BIT_AND_EXPR,
4308 const_binop (LSHIFT_EXPR,
4309 fold_convert_loc (loc, unsigned_type, rhs),
4310 size_int (lbitpos), 0),
4313 lhs = build2 (code, compare_type,
4314 build2 (BIT_AND_EXPR, unsigned_type, lhs, mask),
4316 SET_EXPR_LOCATION (lhs, loc);
4320 /* Subroutine for fold_truthop: decode a field reference.
4322 If EXP is a comparison reference, we return the innermost reference.
4324 *PBITSIZE is set to the number of bits in the reference, *PBITPOS is
4325 set to the starting bit number.
4327 If the innermost field can be completely contained in a mode-sized
4328 unit, *PMODE is set to that mode. Otherwise, it is set to VOIDmode.
4330 *PVOLATILEP is set to 1 if the any expression encountered is volatile;
4331 otherwise it is not changed.
4333 *PUNSIGNEDP is set to the signedness of the field.
4335 *PMASK is set to the mask used. This is either contained in a
4336 BIT_AND_EXPR or derived from the width of the field.
4338 *PAND_MASK is set to the mask found in a BIT_AND_EXPR, if any.
4340 Return 0 if this is not a component reference or is one that we can't
4341 do anything with. */
4344 decode_field_reference (location_t loc, tree exp, HOST_WIDE_INT *pbitsize,
4345 HOST_WIDE_INT *pbitpos, enum machine_mode *pmode,
4346 int *punsignedp, int *pvolatilep,
4347 tree *pmask, tree *pand_mask)
4349 tree outer_type = 0;
4351 tree mask, inner, offset;
4353 unsigned int precision;
4355 /* All the optimizations using this function assume integer fields.
4356 There are problems with FP fields since the type_for_size call
4357 below can fail for, e.g., XFmode. */
4358 if (! INTEGRAL_TYPE_P (TREE_TYPE (exp)))
4361 /* We are interested in the bare arrangement of bits, so strip everything
4362 that doesn't affect the machine mode. However, record the type of the
4363 outermost expression if it may matter below. */
4364 if (CONVERT_EXPR_P (exp)
4365 || TREE_CODE (exp) == NON_LVALUE_EXPR)
4366 outer_type = TREE_TYPE (exp);
4369 if (TREE_CODE (exp) == BIT_AND_EXPR)
4371 and_mask = TREE_OPERAND (exp, 1);
4372 exp = TREE_OPERAND (exp, 0);
4373 STRIP_NOPS (exp); STRIP_NOPS (and_mask);
4374 if (TREE_CODE (and_mask) != INTEGER_CST)
4378 inner = get_inner_reference (exp, pbitsize, pbitpos, &offset, pmode,
4379 punsignedp, pvolatilep, false);
4380 if ((inner == exp && and_mask == 0)
4381 || *pbitsize < 0 || offset != 0
4382 || TREE_CODE (inner) == PLACEHOLDER_EXPR)
4385 /* If the number of bits in the reference is the same as the bitsize of
4386 the outer type, then the outer type gives the signedness. Otherwise
4387 (in case of a small bitfield) the signedness is unchanged. */
4388 if (outer_type && *pbitsize == TYPE_PRECISION (outer_type))
4389 *punsignedp = TYPE_UNSIGNED (outer_type);
4391 /* Compute the mask to access the bitfield. */
4392 unsigned_type = lang_hooks.types.type_for_size (*pbitsize, 1);
4393 precision = TYPE_PRECISION (unsigned_type);
4395 mask = build_int_cst_type (unsigned_type, -1);
4397 mask = const_binop (LSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4398 mask = const_binop (RSHIFT_EXPR, mask, size_int (precision - *pbitsize), 0);
4400 /* Merge it with the mask we found in the BIT_AND_EXPR, if any. */
4402 mask = fold_build2_loc (loc, BIT_AND_EXPR, unsigned_type,
4403 fold_convert_loc (loc, unsigned_type, and_mask), mask);
4406 *pand_mask = and_mask;
4410 /* Return nonzero if MASK represents a mask of SIZE ones in the low-order
4414 all_ones_mask_p (const_tree mask, int size)
4416 tree type = TREE_TYPE (mask);
4417 unsigned int precision = TYPE_PRECISION (type);
4420 tmask = build_int_cst_type (signed_type_for (type), -1);
4423 tree_int_cst_equal (mask,
4424 const_binop (RSHIFT_EXPR,
4425 const_binop (LSHIFT_EXPR, tmask,
4426 size_int (precision - size),
4428 size_int (precision - size), 0));
4431 /* Subroutine for fold: determine if VAL is the INTEGER_CONST that
4432 represents the sign bit of EXP's type. If EXP represents a sign
4433 or zero extension, also test VAL against the unextended type.
4434 The return value is the (sub)expression whose sign bit is VAL,
4435 or NULL_TREE otherwise. */
4438 sign_bit_p (tree exp, const_tree val)
4440 unsigned HOST_WIDE_INT mask_lo, lo;
4441 HOST_WIDE_INT mask_hi, hi;
4445 /* Tree EXP must have an integral type. */
4446 t = TREE_TYPE (exp);
4447 if (! INTEGRAL_TYPE_P (t))
4450 /* Tree VAL must be an integer constant. */
4451 if (TREE_CODE (val) != INTEGER_CST
4452 || TREE_OVERFLOW (val))
4455 width = TYPE_PRECISION (t);
4456 if (width > HOST_BITS_PER_WIDE_INT)
4458 hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
4461 mask_hi = ((unsigned HOST_WIDE_INT) -1
4462 >> (2 * HOST_BITS_PER_WIDE_INT - width));
4468 lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
4471 mask_lo = ((unsigned HOST_WIDE_INT) -1
4472 >> (HOST_BITS_PER_WIDE_INT - width));
4475 /* We mask off those bits beyond TREE_TYPE (exp) so that we can
4476 treat VAL as if it were unsigned. */
4477 if ((TREE_INT_CST_HIGH (val) & mask_hi) == hi
4478 && (TREE_INT_CST_LOW (val) & mask_lo) == lo)
4481 /* Handle extension from a narrower type. */
4482 if (TREE_CODE (exp) == NOP_EXPR
4483 && TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0))) < width)
4484 return sign_bit_p (TREE_OPERAND (exp, 0), val);
4489 /* Subroutine for fold_truthop: determine if an operand is simple enough
4490 to be evaluated unconditionally. */
4493 simple_operand_p (const_tree exp)
4495 /* Strip any conversions that don't change the machine mode. */
4498 return (CONSTANT_CLASS_P (exp)
4499 || TREE_CODE (exp) == SSA_NAME
4501 && ! TREE_ADDRESSABLE (exp)
4502 && ! TREE_THIS_VOLATILE (exp)
4503 && ! DECL_NONLOCAL (exp)
4504 /* Don't regard global variables as simple. They may be
4505 allocated in ways unknown to the compiler (shared memory,
4506 #pragma weak, etc). */
4507 && ! TREE_PUBLIC (exp)
4508 && ! DECL_EXTERNAL (exp)
4509 /* Loading a static variable is unduly expensive, but global
4510 registers aren't expensive. */
4511 && (! TREE_STATIC (exp) || DECL_REGISTER (exp))));
4514 /* The following functions are subroutines to fold_range_test and allow it to
4515 try to change a logical combination of comparisons into a range test.
4518 X == 2 || X == 3 || X == 4 || X == 5
4522 (unsigned) (X - 2) <= 3
4524 We describe each set of comparisons as being either inside or outside
4525 a range, using a variable named like IN_P, and then describe the
4526 range with a lower and upper bound. If one of the bounds is omitted,
4527 it represents either the highest or lowest value of the type.
4529 In the comments below, we represent a range by two numbers in brackets
4530 preceded by a "+" to designate being inside that range, or a "-" to
4531 designate being outside that range, so the condition can be inverted by
4532 flipping the prefix. An omitted bound is represented by a "-". For
4533 example, "- [-, 10]" means being outside the range starting at the lowest
4534 possible value and ending at 10, in other words, being greater than 10.
4535 The range "+ [-, -]" is always true and hence the range "- [-, -]" is
4538 We set up things so that the missing bounds are handled in a consistent
4539 manner so neither a missing bound nor "true" and "false" need to be
4540 handled using a special case. */
4542 /* Return the result of applying CODE to ARG0 and ARG1, but handle the case
4543 of ARG0 and/or ARG1 being omitted, meaning an unlimited range. UPPER0_P
4544 and UPPER1_P are nonzero if the respective argument is an upper bound
4545 and zero for a lower. TYPE, if nonzero, is the type of the result; it
4546 must be specified for a comparison. ARG1 will be converted to ARG0's
4547 type if both are specified. */
4550 range_binop (enum tree_code code, tree type, tree arg0, int upper0_p,
4551 tree arg1, int upper1_p)
4557 /* If neither arg represents infinity, do the normal operation.
4558 Else, if not a comparison, return infinity. Else handle the special
4559 comparison rules. Note that most of the cases below won't occur, but
4560 are handled for consistency. */
4562 if (arg0 != 0 && arg1 != 0)
4564 tem = fold_build2 (code, type != 0 ? type : TREE_TYPE (arg0),
4565 arg0, fold_convert (TREE_TYPE (arg0), arg1));
4567 return TREE_CODE (tem) == INTEGER_CST ? tem : 0;
4570 if (TREE_CODE_CLASS (code) != tcc_comparison)
4573 /* Set SGN[01] to -1 if ARG[01] is a lower bound, 1 for upper, and 0
4574 for neither. In real maths, we cannot assume open ended ranges are
4575 the same. But, this is computer arithmetic, where numbers are finite.
4576 We can therefore make the transformation of any unbounded range with
4577 the value Z, Z being greater than any representable number. This permits
4578 us to treat unbounded ranges as equal. */
4579 sgn0 = arg0 != 0 ? 0 : (upper0_p ? 1 : -1);
4580 sgn1 = arg1 != 0 ? 0 : (upper1_p ? 1 : -1);
4584 result = sgn0 == sgn1;
4587 result = sgn0 != sgn1;
4590 result = sgn0 < sgn1;
4593 result = sgn0 <= sgn1;
4596 result = sgn0 > sgn1;
4599 result = sgn0 >= sgn1;
4605 return constant_boolean_node (result, type);
4608 /* Given EXP, a logical expression, set the range it is testing into
4609 variables denoted by PIN_P, PLOW, and PHIGH. Return the expression
4610 actually being tested. *PLOW and *PHIGH will be made of the same
4611 type as the returned expression. If EXP is not a comparison, we
4612 will most likely not be returning a useful value and range. Set
4613 *STRICT_OVERFLOW_P to true if the return value is only valid
4614 because signed overflow is undefined; otherwise, do not change
4615 *STRICT_OVERFLOW_P. */
4618 make_range (tree exp, int *pin_p, tree *plow, tree *phigh,
4619 bool *strict_overflow_p)
4621 enum tree_code code;
4622 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
4623 tree exp_type = NULL_TREE, arg0_type = NULL_TREE;
4625 tree low, high, n_low, n_high;
4626 location_t loc = EXPR_LOCATION (exp);
4628 /* Start with simply saying "EXP != 0" and then look at the code of EXP
4629 and see if we can refine the range. Some of the cases below may not
4630 happen, but it doesn't seem worth worrying about this. We "continue"
4631 the outer loop when we've changed something; otherwise we "break"
4632 the switch, which will "break" the while. */
4635 low = high = build_int_cst (TREE_TYPE (exp), 0);
4639 code = TREE_CODE (exp);
4640 exp_type = TREE_TYPE (exp);
4642 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
4644 if (TREE_OPERAND_LENGTH (exp) > 0)
4645 arg0 = TREE_OPERAND (exp, 0);
4646 if (TREE_CODE_CLASS (code) == tcc_comparison
4647 || TREE_CODE_CLASS (code) == tcc_unary
4648 || TREE_CODE_CLASS (code) == tcc_binary)
4649 arg0_type = TREE_TYPE (arg0);
4650 if (TREE_CODE_CLASS (code) == tcc_binary
4651 || TREE_CODE_CLASS (code) == tcc_comparison
4652 || (TREE_CODE_CLASS (code) == tcc_expression
4653 && TREE_OPERAND_LENGTH (exp) > 1))
4654 arg1 = TREE_OPERAND (exp, 1);
4659 case TRUTH_NOT_EXPR:
4660 in_p = ! in_p, exp = arg0;
4663 case EQ_EXPR: case NE_EXPR:
4664 case LT_EXPR: case LE_EXPR: case GE_EXPR: case GT_EXPR:
4665 /* We can only do something if the range is testing for zero
4666 and if the second operand is an integer constant. Note that
4667 saying something is "in" the range we make is done by
4668 complementing IN_P since it will set in the initial case of
4669 being not equal to zero; "out" is leaving it alone. */
4670 if (low == 0 || high == 0
4671 || ! integer_zerop (low) || ! integer_zerop (high)
4672 || TREE_CODE (arg1) != INTEGER_CST)
4677 case NE_EXPR: /* - [c, c] */
4680 case EQ_EXPR: /* + [c, c] */
4681 in_p = ! in_p, low = high = arg1;
4683 case GT_EXPR: /* - [-, c] */
4684 low = 0, high = arg1;
4686 case GE_EXPR: /* + [c, -] */
4687 in_p = ! in_p, low = arg1, high = 0;
4689 case LT_EXPR: /* - [c, -] */
4690 low = arg1, high = 0;
4692 case LE_EXPR: /* + [-, c] */
4693 in_p = ! in_p, low = 0, high = arg1;
4699 /* If this is an unsigned comparison, we also know that EXP is
4700 greater than or equal to zero. We base the range tests we make
4701 on that fact, so we record it here so we can parse existing
4702 range tests. We test arg0_type since often the return type
4703 of, e.g. EQ_EXPR, is boolean. */
4704 if (TYPE_UNSIGNED (arg0_type) && (low == 0 || high == 0))
4706 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4708 build_int_cst (arg0_type, 0),
4712 in_p = n_in_p, low = n_low, high = n_high;
4714 /* If the high bound is missing, but we have a nonzero low
4715 bound, reverse the range so it goes from zero to the low bound
4717 if (high == 0 && low && ! integer_zerop (low))
4720 high = range_binop (MINUS_EXPR, NULL_TREE, low, 0,
4721 integer_one_node, 0);
4722 low = build_int_cst (arg0_type, 0);
4730 /* (-x) IN [a,b] -> x in [-b, -a] */
4731 n_low = range_binop (MINUS_EXPR, exp_type,
4732 build_int_cst (exp_type, 0),
4734 n_high = range_binop (MINUS_EXPR, exp_type,
4735 build_int_cst (exp_type, 0),
4737 low = n_low, high = n_high;
4743 exp = build2 (MINUS_EXPR, exp_type, negate_expr (arg0),
4744 build_int_cst (exp_type, 1));
4745 SET_EXPR_LOCATION (exp, loc);
4748 case PLUS_EXPR: case MINUS_EXPR:
4749 if (TREE_CODE (arg1) != INTEGER_CST)
4752 /* If flag_wrapv and ARG0_TYPE is signed, then we cannot
4753 move a constant to the other side. */
4754 if (!TYPE_UNSIGNED (arg0_type)
4755 && !TYPE_OVERFLOW_UNDEFINED (arg0_type))
4758 /* If EXP is signed, any overflow in the computation is undefined,
4759 so we don't worry about it so long as our computations on
4760 the bounds don't overflow. For unsigned, overflow is defined
4761 and this is exactly the right thing. */
4762 n_low = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4763 arg0_type, low, 0, arg1, 0);
4764 n_high = range_binop (code == MINUS_EXPR ? PLUS_EXPR : MINUS_EXPR,
4765 arg0_type, high, 1, arg1, 0);
4766 if ((n_low != 0 && TREE_OVERFLOW (n_low))
4767 || (n_high != 0 && TREE_OVERFLOW (n_high)))
4770 if (TYPE_OVERFLOW_UNDEFINED (arg0_type))
4771 *strict_overflow_p = true;
4773 /* Check for an unsigned range which has wrapped around the maximum
4774 value thus making n_high < n_low, and normalize it. */
4775 if (n_low && n_high && tree_int_cst_lt (n_high, n_low))
4777 low = range_binop (PLUS_EXPR, arg0_type, n_high, 0,
4778 integer_one_node, 0);
4779 high = range_binop (MINUS_EXPR, arg0_type, n_low, 0,
4780 integer_one_node, 0);
4782 /* If the range is of the form +/- [ x+1, x ], we won't
4783 be able to normalize it. But then, it represents the
4784 whole range or the empty set, so make it
4786 if (tree_int_cst_equal (n_low, low)
4787 && tree_int_cst_equal (n_high, high))
4793 low = n_low, high = n_high;
4798 CASE_CONVERT: case NON_LVALUE_EXPR:
4799 if (TYPE_PRECISION (arg0_type) > TYPE_PRECISION (exp_type))
4802 if (! INTEGRAL_TYPE_P (arg0_type)
4803 || (low != 0 && ! int_fits_type_p (low, arg0_type))
4804 || (high != 0 && ! int_fits_type_p (high, arg0_type)))
4807 n_low = low, n_high = high;
4810 n_low = fold_convert_loc (loc, arg0_type, n_low);
4813 n_high = fold_convert_loc (loc, arg0_type, n_high);
4816 /* If we're converting arg0 from an unsigned type, to exp,
4817 a signed type, we will be doing the comparison as unsigned.
4818 The tests above have already verified that LOW and HIGH
4821 So we have to ensure that we will handle large unsigned
4822 values the same way that the current signed bounds treat
4825 if (!TYPE_UNSIGNED (exp_type) && TYPE_UNSIGNED (arg0_type))
4829 /* For fixed-point modes, we need to pass the saturating flag
4830 as the 2nd parameter. */
4831 if (ALL_FIXED_POINT_MODE_P (TYPE_MODE (arg0_type)))
4832 equiv_type = lang_hooks.types.type_for_mode
4833 (TYPE_MODE (arg0_type),
4834 TYPE_SATURATING (arg0_type));
4836 equiv_type = lang_hooks.types.type_for_mode
4837 (TYPE_MODE (arg0_type), 1);
4839 /* A range without an upper bound is, naturally, unbounded.
4840 Since convert would have cropped a very large value, use
4841 the max value for the destination type. */
4843 = TYPE_MAX_VALUE (equiv_type) ? TYPE_MAX_VALUE (equiv_type)
4844 : TYPE_MAX_VALUE (arg0_type);
4846 if (TYPE_PRECISION (exp_type) == TYPE_PRECISION (arg0_type))
4847 high_positive = fold_build2_loc (loc, RSHIFT_EXPR, arg0_type,
4848 fold_convert_loc (loc, arg0_type,
4850 build_int_cst (arg0_type, 1));
4852 /* If the low bound is specified, "and" the range with the
4853 range for which the original unsigned value will be
4857 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4858 1, n_low, n_high, 1,
4859 fold_convert_loc (loc, arg0_type,
4864 in_p = (n_in_p == in_p);
4868 /* Otherwise, "or" the range with the range of the input
4869 that will be interpreted as negative. */
4870 if (! merge_ranges (&n_in_p, &n_low, &n_high,
4871 0, n_low, n_high, 1,
4872 fold_convert_loc (loc, arg0_type,
4877 in_p = (in_p != n_in_p);
4882 low = n_low, high = n_high;
4892 /* If EXP is a constant, we can evaluate whether this is true or false. */
4893 if (TREE_CODE (exp) == INTEGER_CST)
4895 in_p = in_p == (integer_onep (range_binop (GE_EXPR, integer_type_node,
4897 && integer_onep (range_binop (LE_EXPR, integer_type_node,
4903 *pin_p = in_p, *plow = low, *phigh = high;
4907 /* Given a range, LOW, HIGH, and IN_P, an expression, EXP, and a result
4908 type, TYPE, return an expression to test if EXP is in (or out of, depending
4909 on IN_P) the range. Return 0 if the test couldn't be created. */
4912 build_range_check (location_t loc, tree type, tree exp, int in_p,
4913 tree low, tree high)
4915 tree etype = TREE_TYPE (exp), value;
4917 #ifdef HAVE_canonicalize_funcptr_for_compare
4918 /* Disable this optimization for function pointer expressions
4919 on targets that require function pointer canonicalization. */
4920 if (HAVE_canonicalize_funcptr_for_compare
4921 && TREE_CODE (etype) == POINTER_TYPE
4922 && TREE_CODE (TREE_TYPE (etype)) == FUNCTION_TYPE)
4928 value = build_range_check (loc, type, exp, 1, low, high);
4930 return invert_truthvalue_loc (loc, value);
4935 if (low == 0 && high == 0)
4936 return build_int_cst (type, 1);
4939 return fold_build2_loc (loc, LE_EXPR, type, exp,
4940 fold_convert_loc (loc, etype, high));
4943 return fold_build2_loc (loc, GE_EXPR, type, exp,
4944 fold_convert_loc (loc, etype, low));
4946 if (operand_equal_p (low, high, 0))
4947 return fold_build2_loc (loc, EQ_EXPR, type, exp,
4948 fold_convert_loc (loc, etype, low));
4950 if (integer_zerop (low))
4952 if (! TYPE_UNSIGNED (etype))
4954 etype = unsigned_type_for (etype);
4955 high = fold_convert_loc (loc, etype, high);
4956 exp = fold_convert_loc (loc, etype, exp);
4958 return build_range_check (loc, type, exp, 1, 0, high);
4961 /* Optimize (c>=1) && (c<=127) into (signed char)c > 0. */
4962 if (integer_onep (low) && TREE_CODE (high) == INTEGER_CST)
4964 unsigned HOST_WIDE_INT lo;
4968 prec = TYPE_PRECISION (etype);
4969 if (prec <= HOST_BITS_PER_WIDE_INT)
4972 lo = ((unsigned HOST_WIDE_INT) 1 << (prec - 1)) - 1;
4976 hi = ((HOST_WIDE_INT) 1 << (prec - HOST_BITS_PER_WIDE_INT - 1)) - 1;
4977 lo = (unsigned HOST_WIDE_INT) -1;
4980 if (TREE_INT_CST_HIGH (high) == hi && TREE_INT_CST_LOW (high) == lo)
4982 if (TYPE_UNSIGNED (etype))
4984 tree signed_etype = signed_type_for (etype);
4985 if (TYPE_PRECISION (signed_etype) != TYPE_PRECISION (etype))
4987 = build_nonstandard_integer_type (TYPE_PRECISION (etype), 0);
4989 etype = signed_etype;
4990 exp = fold_convert_loc (loc, etype, exp);
4992 return fold_build2_loc (loc, GT_EXPR, type, exp,
4993 build_int_cst (etype, 0));
4997 /* Optimize (c>=low) && (c<=high) into (c-low>=0) && (c-low<=high-low).
4998 This requires wrap-around arithmetics for the type of the expression.
4999 First make sure that arithmetics in this type is valid, then make sure
5000 that it wraps around. */
5001 if (TREE_CODE (etype) == ENUMERAL_TYPE || TREE_CODE (etype) == BOOLEAN_TYPE)
5002 etype = lang_hooks.types.type_for_size (TYPE_PRECISION (etype),
5003 TYPE_UNSIGNED (etype));
5005 if (TREE_CODE (etype) == INTEGER_TYPE && !TYPE_OVERFLOW_WRAPS (etype))
5007 tree utype, minv, maxv;
5009 /* Check if (unsigned) INT_MAX + 1 == (unsigned) INT_MIN
5010 for the type in question, as we rely on this here. */
5011 utype = unsigned_type_for (etype);
5012 maxv = fold_convert_loc (loc, utype, TYPE_MAX_VALUE (etype));
5013 maxv = range_binop (PLUS_EXPR, NULL_TREE, maxv, 1,
5014 integer_one_node, 1);
5015 minv = fold_convert_loc (loc, utype, TYPE_MIN_VALUE (etype));
5017 if (integer_zerop (range_binop (NE_EXPR, integer_type_node,
5024 high = fold_convert_loc (loc, etype, high);
5025 low = fold_convert_loc (loc, etype, low);
5026 exp = fold_convert_loc (loc, etype, exp);
5028 value = const_binop (MINUS_EXPR, high, low, 0);
5031 if (POINTER_TYPE_P (etype))
5033 if (value != 0 && !TREE_OVERFLOW (value))
5035 low = fold_convert_loc (loc, sizetype, low);
5036 low = fold_build1_loc (loc, NEGATE_EXPR, sizetype, low);
5037 return build_range_check (loc, type,
5038 fold_build2_loc (loc, POINTER_PLUS_EXPR,
5040 1, build_int_cst (etype, 0), value);
5045 if (value != 0 && !TREE_OVERFLOW (value))
5046 return build_range_check (loc, type,
5047 fold_build2_loc (loc, MINUS_EXPR, etype, exp, low),
5048 1, build_int_cst (etype, 0), value);
5053 /* Return the predecessor of VAL in its type, handling the infinite case. */
5056 range_predecessor (tree val)
5058 tree type = TREE_TYPE (val);
5060 if (INTEGRAL_TYPE_P (type)
5061 && operand_equal_p (val, TYPE_MIN_VALUE (type), 0))
5064 return range_binop (MINUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
5067 /* Return the successor of VAL in its type, handling the infinite case. */
5070 range_successor (tree val)
5072 tree type = TREE_TYPE (val);
5074 if (INTEGRAL_TYPE_P (type)
5075 && operand_equal_p (val, TYPE_MAX_VALUE (type), 0))
5078 return range_binop (PLUS_EXPR, NULL_TREE, val, 0, integer_one_node, 0);
5081 /* Given two ranges, see if we can merge them into one. Return 1 if we
5082 can, 0 if we can't. Set the output range into the specified parameters. */
5085 merge_ranges (int *pin_p, tree *plow, tree *phigh, int in0_p, tree low0,
5086 tree high0, int in1_p, tree low1, tree high1)
5094 int lowequal = ((low0 == 0 && low1 == 0)
5095 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
5096 low0, 0, low1, 0)));
5097 int highequal = ((high0 == 0 && high1 == 0)
5098 || integer_onep (range_binop (EQ_EXPR, integer_type_node,
5099 high0, 1, high1, 1)));
5101 /* Make range 0 be the range that starts first, or ends last if they
5102 start at the same value. Swap them if it isn't. */
5103 if (integer_onep (range_binop (GT_EXPR, integer_type_node,
5106 && integer_onep (range_binop (GT_EXPR, integer_type_node,
5107 high1, 1, high0, 1))))
5109 temp = in0_p, in0_p = in1_p, in1_p = temp;
5110 tem = low0, low0 = low1, low1 = tem;
5111 tem = high0, high0 = high1, high1 = tem;
5114 /* Now flag two cases, whether the ranges are disjoint or whether the
5115 second range is totally subsumed in the first. Note that the tests
5116 below are simplified by the ones above. */
5117 no_overlap = integer_onep (range_binop (LT_EXPR, integer_type_node,
5118 high0, 1, low1, 0));
5119 subset = integer_onep (range_binop (LE_EXPR, integer_type_node,
5120 high1, 1, high0, 1));
5122 /* We now have four cases, depending on whether we are including or
5123 excluding the two ranges. */
5126 /* If they don't overlap, the result is false. If the second range
5127 is a subset it is the result. Otherwise, the range is from the start
5128 of the second to the end of the first. */
5130 in_p = 0, low = high = 0;
5132 in_p = 1, low = low1, high = high1;
5134 in_p = 1, low = low1, high = high0;
5137 else if (in0_p && ! in1_p)
5139 /* If they don't overlap, the result is the first range. If they are
5140 equal, the result is false. If the second range is a subset of the
5141 first, and the ranges begin at the same place, we go from just after
5142 the end of the second range to the end of the first. If the second
5143 range is not a subset of the first, or if it is a subset and both
5144 ranges end at the same place, the range starts at the start of the
5145 first range and ends just before the second range.
5146 Otherwise, we can't describe this as a single range. */
5148 in_p = 1, low = low0, high = high0;
5149 else if (lowequal && highequal)
5150 in_p = 0, low = high = 0;
5151 else if (subset && lowequal)
5153 low = range_successor (high1);
5158 /* We are in the weird situation where high0 > high1 but
5159 high1 has no successor. Punt. */
5163 else if (! subset || highequal)
5166 high = range_predecessor (low1);
5170 /* low0 < low1 but low1 has no predecessor. Punt. */
5178 else if (! in0_p && in1_p)
5180 /* If they don't overlap, the result is the second range. If the second
5181 is a subset of the first, the result is false. Otherwise,
5182 the range starts just after the first range and ends at the
5183 end of the second. */
5185 in_p = 1, low = low1, high = high1;
5186 else if (subset || highequal)
5187 in_p = 0, low = high = 0;
5190 low = range_successor (high0);
5195 /* high1 > high0 but high0 has no successor. Punt. */
5203 /* The case where we are excluding both ranges. Here the complex case
5204 is if they don't overlap. In that case, the only time we have a
5205 range is if they are adjacent. If the second is a subset of the
5206 first, the result is the first. Otherwise, the range to exclude
5207 starts at the beginning of the first range and ends at the end of the
5211 if (integer_onep (range_binop (EQ_EXPR, integer_type_node,
5212 range_successor (high0),
5214 in_p = 0, low = low0, high = high1;
5217 /* Canonicalize - [min, x] into - [-, x]. */
5218 if (low0 && TREE_CODE (low0) == INTEGER_CST)
5219 switch (TREE_CODE (TREE_TYPE (low0)))
5222 if (TYPE_PRECISION (TREE_TYPE (low0))
5223 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (low0))))
5227 if (tree_int_cst_equal (low0,
5228 TYPE_MIN_VALUE (TREE_TYPE (low0))))
5232 if (TYPE_UNSIGNED (TREE_TYPE (low0))
5233 && integer_zerop (low0))
5240 /* Canonicalize - [x, max] into - [x, -]. */
5241 if (high1 && TREE_CODE (high1) == INTEGER_CST)
5242 switch (TREE_CODE (TREE_TYPE (high1)))
5245 if (TYPE_PRECISION (TREE_TYPE (high1))
5246 != GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (high1))))
5250 if (tree_int_cst_equal (high1,
5251 TYPE_MAX_VALUE (TREE_TYPE (high1))))
5255 if (TYPE_UNSIGNED (TREE_TYPE (high1))
5256 && integer_zerop (range_binop (PLUS_EXPR, NULL_TREE,
5258 integer_one_node, 1)))
5265 /* The ranges might be also adjacent between the maximum and
5266 minimum values of the given type. For
5267 - [{min,-}, x] and - [y, {max,-}] ranges where x + 1 < y
5268 return + [x + 1, y - 1]. */
5269 if (low0 == 0 && high1 == 0)
5271 low = range_successor (high0);
5272 high = range_predecessor (low1);
5273 if (low == 0 || high == 0)
5283 in_p = 0, low = low0, high = high0;
5285 in_p = 0, low = low0, high = high1;
5288 *pin_p = in_p, *plow = low, *phigh = high;
5293 /* Subroutine of fold, looking inside expressions of the form
5294 A op B ? A : C, where ARG0, ARG1 and ARG2 are the three operands
5295 of the COND_EXPR. This function is being used also to optimize
5296 A op B ? C : A, by reversing the comparison first.
5298 Return a folded expression whose code is not a COND_EXPR
5299 anymore, or NULL_TREE if no folding opportunity is found. */
5302 fold_cond_expr_with_comparison (location_t loc, tree type,
5303 tree arg0, tree arg1, tree arg2)
5305 enum tree_code comp_code = TREE_CODE (arg0);
5306 tree arg00 = TREE_OPERAND (arg0, 0);
5307 tree arg01 = TREE_OPERAND (arg0, 1);
5308 tree arg1_type = TREE_TYPE (arg1);
5314 /* If we have A op 0 ? A : -A, consider applying the following
5317 A == 0? A : -A same as -A
5318 A != 0? A : -A same as A
5319 A >= 0? A : -A same as abs (A)
5320 A > 0? A : -A same as abs (A)
5321 A <= 0? A : -A same as -abs (A)
5322 A < 0? A : -A same as -abs (A)
5324 None of these transformations work for modes with signed
5325 zeros. If A is +/-0, the first two transformations will
5326 change the sign of the result (from +0 to -0, or vice
5327 versa). The last four will fix the sign of the result,
5328 even though the original expressions could be positive or
5329 negative, depending on the sign of A.
5331 Note that all these transformations are correct if A is
5332 NaN, since the two alternatives (A and -A) are also NaNs. */
5333 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5334 && (FLOAT_TYPE_P (TREE_TYPE (arg01))
5335 ? real_zerop (arg01)
5336 : integer_zerop (arg01))
5337 && ((TREE_CODE (arg2) == NEGATE_EXPR
5338 && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0))
5339 /* In the case that A is of the form X-Y, '-A' (arg2) may
5340 have already been folded to Y-X, check for that. */
5341 || (TREE_CODE (arg1) == MINUS_EXPR
5342 && TREE_CODE (arg2) == MINUS_EXPR
5343 && operand_equal_p (TREE_OPERAND (arg1, 0),
5344 TREE_OPERAND (arg2, 1), 0)
5345 && operand_equal_p (TREE_OPERAND (arg1, 1),
5346 TREE_OPERAND (arg2, 0), 0))))
5351 tem = fold_convert_loc (loc, arg1_type, arg1);
5352 return pedantic_non_lvalue_loc (loc,
5353 fold_convert_loc (loc, type,
5354 negate_expr (tem)));
5357 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5360 if (flag_trapping_math)
5365 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5366 arg1 = fold_convert_loc (loc, signed_type_for
5367 (TREE_TYPE (arg1)), arg1);
5368 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
5369 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5372 if (flag_trapping_math)
5376 if (TYPE_UNSIGNED (TREE_TYPE (arg1)))
5377 arg1 = fold_convert_loc (loc, signed_type_for
5378 (TREE_TYPE (arg1)), arg1);
5379 tem = fold_build1_loc (loc, ABS_EXPR, TREE_TYPE (arg1), arg1);
5380 return negate_expr (fold_convert_loc (loc, type, tem));
5382 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5386 /* A != 0 ? A : 0 is simply A, unless A is -0. Likewise
5387 A == 0 ? A : 0 is always 0 unless A is -0. Note that
5388 both transformations are correct when A is NaN: A != 0
5389 is then true, and A == 0 is false. */
5391 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5392 && integer_zerop (arg01) && integer_zerop (arg2))
5394 if (comp_code == NE_EXPR)
5395 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5396 else if (comp_code == EQ_EXPR)
5397 return build_int_cst (type, 0);
5400 /* Try some transformations of A op B ? A : B.
5402 A == B? A : B same as B
5403 A != B? A : B same as A
5404 A >= B? A : B same as max (A, B)
5405 A > B? A : B same as max (B, A)
5406 A <= B? A : B same as min (A, B)
5407 A < B? A : B same as min (B, A)
5409 As above, these transformations don't work in the presence
5410 of signed zeros. For example, if A and B are zeros of
5411 opposite sign, the first two transformations will change
5412 the sign of the result. In the last four, the original
5413 expressions give different results for (A=+0, B=-0) and
5414 (A=-0, B=+0), but the transformed expressions do not.
5416 The first two transformations are correct if either A or B
5417 is a NaN. In the first transformation, the condition will
5418 be false, and B will indeed be chosen. In the case of the
5419 second transformation, the condition A != B will be true,
5420 and A will be chosen.
5422 The conversions to max() and min() are not correct if B is
5423 a number and A is not. The conditions in the original
5424 expressions will be false, so all four give B. The min()
5425 and max() versions would give a NaN instead. */
5426 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type))
5427 && operand_equal_for_comparison_p (arg01, arg2, arg00)
5428 /* Avoid these transformations if the COND_EXPR may be used
5429 as an lvalue in the C++ front-end. PR c++/19199. */
5431 || (strcmp (lang_hooks.name, "GNU C++") != 0
5432 && strcmp (lang_hooks.name, "GNU Objective-C++") != 0)
5433 || ! maybe_lvalue_p (arg1)
5434 || ! maybe_lvalue_p (arg2)))
5436 tree comp_op0 = arg00;
5437 tree comp_op1 = arg01;
5438 tree comp_type = TREE_TYPE (comp_op0);
5440 /* Avoid adding NOP_EXPRs in case this is an lvalue. */
5441 if (TYPE_MAIN_VARIANT (comp_type) == TYPE_MAIN_VARIANT (type))
5451 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg2));
5453 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
5458 /* In C++ a ?: expression can be an lvalue, so put the
5459 operand which will be used if they are equal first
5460 so that we can convert this back to the
5461 corresponding COND_EXPR. */
5462 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5464 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
5465 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
5466 tem = (comp_code == LE_EXPR || comp_code == UNLE_EXPR)
5467 ? fold_build2_loc (loc, MIN_EXPR, comp_type, comp_op0, comp_op1)
5468 : fold_build2_loc (loc, MIN_EXPR, comp_type,
5469 comp_op1, comp_op0);
5470 return pedantic_non_lvalue_loc (loc,
5471 fold_convert_loc (loc, type, tem));
5478 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5480 comp_op0 = fold_convert_loc (loc, comp_type, comp_op0);
5481 comp_op1 = fold_convert_loc (loc, comp_type, comp_op1);
5482 tem = (comp_code == GE_EXPR || comp_code == UNGE_EXPR)
5483 ? fold_build2_loc (loc, MAX_EXPR, comp_type, comp_op0, comp_op1)
5484 : fold_build2_loc (loc, MAX_EXPR, comp_type,
5485 comp_op1, comp_op0);
5486 return pedantic_non_lvalue_loc (loc,
5487 fold_convert_loc (loc, type, tem));
5491 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5492 return pedantic_non_lvalue_loc (loc,
5493 fold_convert_loc (loc, type, arg2));
5496 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1))))
5497 return pedantic_non_lvalue_loc (loc,
5498 fold_convert_loc (loc, type, arg1));
5501 gcc_assert (TREE_CODE_CLASS (comp_code) == tcc_comparison);
5506 /* If this is A op C1 ? A : C2 with C1 and C2 constant integers,
5507 we might still be able to simplify this. For example,
5508 if C1 is one less or one more than C2, this might have started
5509 out as a MIN or MAX and been transformed by this function.
5510 Only good for INTEGER_TYPEs, because we need TYPE_MAX_VALUE. */
5512 if (INTEGRAL_TYPE_P (type)
5513 && TREE_CODE (arg01) == INTEGER_CST
5514 && TREE_CODE (arg2) == INTEGER_CST)
5518 if (TREE_CODE (arg1) == INTEGER_CST)
5520 /* We can replace A with C1 in this case. */
5521 arg1 = fold_convert_loc (loc, type, arg01);
5522 return fold_build3_loc (loc, COND_EXPR, type, arg0, arg1, arg2);
5525 /* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
5526 MIN_EXPR, to preserve the signedness of the comparison. */
5527 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5529 && operand_equal_p (arg01,
5530 const_binop (PLUS_EXPR, arg2,
5531 build_int_cst (type, 1), 0),
5534 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
5535 fold_convert_loc (loc, TREE_TYPE (arg00),
5537 return pedantic_non_lvalue_loc (loc,
5538 fold_convert_loc (loc, type, tem));
5543 /* If C1 is C2 - 1, this is min(A, C2), with the same care
5545 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5547 && operand_equal_p (arg01,
5548 const_binop (MINUS_EXPR, arg2,
5549 build_int_cst (type, 1), 0),
5552 tem = fold_build2_loc (loc, MIN_EXPR, TREE_TYPE (arg00), arg00,
5553 fold_convert_loc (loc, TREE_TYPE (arg00),
5555 return pedantic_non_lvalue_loc (loc,
5556 fold_convert_loc (loc, type, tem));
5561 /* If C1 is C2 - 1, this is max(A, C2), but use ARG00's type for
5562 MAX_EXPR, to preserve the signedness of the comparison. */
5563 if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
5565 && operand_equal_p (arg01,
5566 const_binop (MINUS_EXPR, arg2,
5567 build_int_cst (type, 1), 0),
5570 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
5571 fold_convert_loc (loc, TREE_TYPE (arg00),
5573 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5578 /* If C1 is C2 + 1, this is max(A, C2), with the same care as above. */
5579 if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
5581 && operand_equal_p (arg01,
5582 const_binop (PLUS_EXPR, arg2,
5583 build_int_cst (type, 1), 0),
5586 tem = fold_build2_loc (loc, MAX_EXPR, TREE_TYPE (arg00), arg00,
5587 fold_convert_loc (loc, TREE_TYPE (arg00),
5589 return pedantic_non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
5603 #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
5604 #define LOGICAL_OP_NON_SHORT_CIRCUIT \
5605 (BRANCH_COST (optimize_function_for_speed_p (cfun), \
5609 /* EXP is some logical combination of boolean tests. See if we can
5610 merge it into some range test. Return the new tree if so. */
5613 fold_range_test (location_t loc, enum tree_code code, tree type,
5616 int or_op = (code == TRUTH_ORIF_EXPR
5617 || code == TRUTH_OR_EXPR);
5618 int in0_p, in1_p, in_p;
5619 tree low0, low1, low, high0, high1, high;
5620 bool strict_overflow_p = false;
5621 tree lhs = make_range (op0, &in0_p, &low0, &high0, &strict_overflow_p);
5622 tree rhs = make_range (op1, &in1_p, &low1, &high1, &strict_overflow_p);
5624 const char * const warnmsg = G_("assuming signed overflow does not occur "
5625 "when simplifying range test");
5627 /* If this is an OR operation, invert both sides; we will invert
5628 again at the end. */
5630 in0_p = ! in0_p, in1_p = ! in1_p;
5632 /* If both expressions are the same, if we can merge the ranges, and we
5633 can build the range test, return it or it inverted. If one of the
5634 ranges is always true or always false, consider it to be the same
5635 expression as the other. */
5636 if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
5637 && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
5639 && 0 != (tem = (build_range_check (UNKNOWN_LOCATION, type,
5641 : rhs != 0 ? rhs : integer_zero_node,
5644 if (strict_overflow_p)
5645 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
5646 return or_op ? invert_truthvalue_loc (loc, tem) : tem;
5649 /* On machines where the branch cost is expensive, if this is a
5650 short-circuited branch and the underlying object on both sides
5651 is the same, make a non-short-circuit operation. */
5652 else if (LOGICAL_OP_NON_SHORT_CIRCUIT
5653 && lhs != 0 && rhs != 0
5654 && (code == TRUTH_ANDIF_EXPR
5655 || code == TRUTH_ORIF_EXPR)
5656 && operand_equal_p (lhs, rhs, 0))
5658 /* If simple enough, just rewrite. Otherwise, make a SAVE_EXPR
5659 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
5660 which cases we can't do this. */
5661 if (simple_operand_p (lhs))
5663 tem = build2 (code == TRUTH_ANDIF_EXPR
5664 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5666 SET_EXPR_LOCATION (tem, loc);
5670 else if (lang_hooks.decls.global_bindings_p () == 0
5671 && ! CONTAINS_PLACEHOLDER_P (lhs))
5673 tree common = save_expr (lhs);
5675 if (0 != (lhs = build_range_check (loc, type, common,
5676 or_op ? ! in0_p : in0_p,
5678 && (0 != (rhs = build_range_check (loc, type, common,
5679 or_op ? ! in1_p : in1_p,
5682 if (strict_overflow_p)
5683 fold_overflow_warning (warnmsg,
5684 WARN_STRICT_OVERFLOW_COMPARISON);
5685 tem = build2 (code == TRUTH_ANDIF_EXPR
5686 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
5688 SET_EXPR_LOCATION (tem, loc);
5697 /* Subroutine for fold_truthop: C is an INTEGER_CST interpreted as a P
5698 bit value. Arrange things so the extra bits will be set to zero if and
5699 only if C is signed-extended to its full width. If MASK is nonzero,
5700 it is an INTEGER_CST that should be AND'ed with the extra bits. */
5703 unextend (tree c, int p, int unsignedp, tree mask)
5705 tree type = TREE_TYPE (c);
5706 int modesize = GET_MODE_BITSIZE (TYPE_MODE (type));
5709 if (p == modesize || unsignedp)
5712 /* We work by getting just the sign bit into the low-order bit, then
5713 into the high-order bit, then sign-extend. We then XOR that value
5715 temp = const_binop (RSHIFT_EXPR, c, size_int (p - 1), 0);
5716 temp = const_binop (BIT_AND_EXPR, temp, size_int (1), 0);
5718 /* We must use a signed type in order to get an arithmetic right shift.
5719 However, we must also avoid introducing accidental overflows, so that
5720 a subsequent call to integer_zerop will work. Hence we must
5721 do the type conversion here. At this point, the constant is either
5722 zero or one, and the conversion to a signed type can never overflow.
5723 We could get an overflow if this conversion is done anywhere else. */
5724 if (TYPE_UNSIGNED (type))
5725 temp = fold_convert (signed_type_for (type), temp);
5727 temp = const_binop (LSHIFT_EXPR, temp, size_int (modesize - 1), 0);
5728 temp = const_binop (RSHIFT_EXPR, temp, size_int (modesize - p - 1), 0);
5730 temp = const_binop (BIT_AND_EXPR, temp,
5731 fold_convert (TREE_TYPE (c), mask),
5733 /* If necessary, convert the type back to match the type of C. */
5734 if (TYPE_UNSIGNED (type))
5735 temp = fold_convert (type, temp);
5737 return fold_convert (type,
5738 const_binop (BIT_XOR_EXPR, c, temp, 0));
5741 /* Find ways of folding logical expressions of LHS and RHS:
5742 Try to merge two comparisons to the same innermost item.
5743 Look for range tests like "ch >= '0' && ch <= '9'".
5744 Look for combinations of simple terms on machines with expensive branches
5745 and evaluate the RHS unconditionally.
5747 For example, if we have p->a == 2 && p->b == 4 and we can make an
5748 object large enough to span both A and B, we can do this with a comparison
5749 against the object ANDed with the a mask.
5751 If we have p->a == q->a && p->b == q->b, we may be able to use bit masking
5752 operations to do this with one comparison.
5754 We check for both normal comparisons and the BIT_AND_EXPRs made this by
5755 function and the one above.
5757 CODE is the logical operation being done. It can be TRUTH_ANDIF_EXPR,
5758 TRUTH_AND_EXPR, TRUTH_ORIF_EXPR, or TRUTH_OR_EXPR.
5760 TRUTH_TYPE is the type of the logical operand and LHS and RHS are its
5763 We return the simplified tree or 0 if no optimization is possible. */
5766 fold_truthop (location_t loc, enum tree_code code, tree truth_type,
5769 /* If this is the "or" of two comparisons, we can do something if
5770 the comparisons are NE_EXPR. If this is the "and", we can do something
5771 if the comparisons are EQ_EXPR. I.e.,
5772 (a->b == 2 && a->c == 4) can become (a->new == NEW).
5774 WANTED_CODE is this operation code. For single bit fields, we can
5775 convert EQ_EXPR to NE_EXPR so we need not reject the "wrong"
5776 comparison for one-bit fields. */
5778 enum tree_code wanted_code;
5779 enum tree_code lcode, rcode;
5780 tree ll_arg, lr_arg, rl_arg, rr_arg;
5781 tree ll_inner, lr_inner, rl_inner, rr_inner;
5782 HOST_WIDE_INT ll_bitsize, ll_bitpos, lr_bitsize, lr_bitpos;
5783 HOST_WIDE_INT rl_bitsize, rl_bitpos, rr_bitsize, rr_bitpos;
5784 HOST_WIDE_INT xll_bitpos, xlr_bitpos, xrl_bitpos, xrr_bitpos;
5785 HOST_WIDE_INT lnbitsize, lnbitpos, rnbitsize, rnbitpos;
5786 int ll_unsignedp, lr_unsignedp, rl_unsignedp, rr_unsignedp;
5787 enum machine_mode ll_mode, lr_mode, rl_mode, rr_mode;
5788 enum machine_mode lnmode, rnmode;
5789 tree ll_mask, lr_mask, rl_mask, rr_mask;
5790 tree ll_and_mask, lr_and_mask, rl_and_mask, rr_and_mask;
5791 tree l_const, r_const;
5792 tree lntype, rntype, result;
5793 HOST_WIDE_INT first_bit, end_bit;
5795 tree orig_lhs = lhs, orig_rhs = rhs;
5796 enum tree_code orig_code = code;
5798 /* Start by getting the comparison codes. Fail if anything is volatile.
5799 If one operand is a BIT_AND_EXPR with the constant one, treat it as if
5800 it were surrounded with a NE_EXPR. */
5802 if (TREE_SIDE_EFFECTS (lhs) || TREE_SIDE_EFFECTS (rhs))
5805 lcode = TREE_CODE (lhs);
5806 rcode = TREE_CODE (rhs);
5808 if (lcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (lhs, 1)))
5810 lhs = build2 (NE_EXPR, truth_type, lhs,
5811 build_int_cst (TREE_TYPE (lhs), 0));
5815 if (rcode == BIT_AND_EXPR && integer_onep (TREE_OPERAND (rhs, 1)))
5817 rhs = build2 (NE_EXPR, truth_type, rhs,
5818 build_int_cst (TREE_TYPE (rhs), 0));
5822 if (TREE_CODE_CLASS (lcode) != tcc_comparison
5823 || TREE_CODE_CLASS (rcode) != tcc_comparison)
5826 ll_arg = TREE_OPERAND (lhs, 0);
5827 lr_arg = TREE_OPERAND (lhs, 1);
5828 rl_arg = TREE_OPERAND (rhs, 0);
5829 rr_arg = TREE_OPERAND (rhs, 1);
5831 /* Simplify (x<y) && (x==y) into (x<=y) and related optimizations. */
5832 if (simple_operand_p (ll_arg)
5833 && simple_operand_p (lr_arg))
5836 if (operand_equal_p (ll_arg, rl_arg, 0)
5837 && operand_equal_p (lr_arg, rr_arg, 0))
5839 result = combine_comparisons (loc, code, lcode, rcode,
5840 truth_type, ll_arg, lr_arg);
5844 else if (operand_equal_p (ll_arg, rr_arg, 0)
5845 && operand_equal_p (lr_arg, rl_arg, 0))
5847 result = combine_comparisons (loc, code, lcode,
5848 swap_tree_comparison (rcode),
5849 truth_type, ll_arg, lr_arg);
5855 code = ((code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR)
5856 ? TRUTH_AND_EXPR : TRUTH_OR_EXPR);
5858 /* If the RHS can be evaluated unconditionally and its operands are
5859 simple, it wins to evaluate the RHS unconditionally on machines
5860 with expensive branches. In this case, this isn't a comparison
5861 that can be merged. Avoid doing this if the RHS is a floating-point
5862 comparison since those can trap. */
5864 if (BRANCH_COST (optimize_function_for_speed_p (cfun),
5866 && ! FLOAT_TYPE_P (TREE_TYPE (rl_arg))
5867 && simple_operand_p (rl_arg)
5868 && simple_operand_p (rr_arg))
5870 /* Convert (a != 0) || (b != 0) into (a | b) != 0. */
5871 if (code == TRUTH_OR_EXPR
5872 && lcode == NE_EXPR && integer_zerop (lr_arg)
5873 && rcode == NE_EXPR && integer_zerop (rr_arg)
5874 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5875 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5877 result = build2 (NE_EXPR, truth_type,
5878 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5880 build_int_cst (TREE_TYPE (ll_arg), 0));
5881 goto fold_truthop_exit;
5884 /* Convert (a == 0) && (b == 0) into (a | b) == 0. */
5885 if (code == TRUTH_AND_EXPR
5886 && lcode == EQ_EXPR && integer_zerop (lr_arg)
5887 && rcode == EQ_EXPR && integer_zerop (rr_arg)
5888 && TREE_TYPE (ll_arg) == TREE_TYPE (rl_arg)
5889 && INTEGRAL_TYPE_P (TREE_TYPE (ll_arg)))
5891 result = build2 (EQ_EXPR, truth_type,
5892 build2 (BIT_IOR_EXPR, TREE_TYPE (ll_arg),
5894 build_int_cst (TREE_TYPE (ll_arg), 0));
5895 goto fold_truthop_exit;
5898 if (LOGICAL_OP_NON_SHORT_CIRCUIT)
5900 if (code != orig_code || lhs != orig_lhs || rhs != orig_rhs)
5902 result = build2 (code, truth_type, lhs, rhs);
5903 goto fold_truthop_exit;
5909 /* See if the comparisons can be merged. Then get all the parameters for
5912 if ((lcode != EQ_EXPR && lcode != NE_EXPR)
5913 || (rcode != EQ_EXPR && rcode != NE_EXPR))
5917 ll_inner = decode_field_reference (loc, ll_arg,
5918 &ll_bitsize, &ll_bitpos, &ll_mode,
5919 &ll_unsignedp, &volatilep, &ll_mask,
5921 lr_inner = decode_field_reference (loc, lr_arg,
5922 &lr_bitsize, &lr_bitpos, &lr_mode,
5923 &lr_unsignedp, &volatilep, &lr_mask,
5925 rl_inner = decode_field_reference (loc, rl_arg,
5926 &rl_bitsize, &rl_bitpos, &rl_mode,
5927 &rl_unsignedp, &volatilep, &rl_mask,
5929 rr_inner = decode_field_reference (loc, rr_arg,
5930 &rr_bitsize, &rr_bitpos, &rr_mode,
5931 &rr_unsignedp, &volatilep, &rr_mask,
5934 /* It must be true that the inner operation on the lhs of each
5935 comparison must be the same if we are to be able to do anything.
5936 Then see if we have constants. If not, the same must be true for
5938 if (volatilep || ll_inner == 0 || rl_inner == 0
5939 || ! operand_equal_p (ll_inner, rl_inner, 0))
5942 if (TREE_CODE (lr_arg) == INTEGER_CST
5943 && TREE_CODE (rr_arg) == INTEGER_CST)
5944 l_const = lr_arg, r_const = rr_arg;
5945 else if (lr_inner == 0 || rr_inner == 0
5946 || ! operand_equal_p (lr_inner, rr_inner, 0))
5949 l_const = r_const = 0;
5951 /* If either comparison code is not correct for our logical operation,
5952 fail. However, we can convert a one-bit comparison against zero into
5953 the opposite comparison against that bit being set in the field. */
5955 wanted_code = (code == TRUTH_AND_EXPR ? EQ_EXPR : NE_EXPR);
5956 if (lcode != wanted_code)
5958 if (l_const && integer_zerop (l_const) && integer_pow2p (ll_mask))
5960 /* Make the left operand unsigned, since we are only interested
5961 in the value of one bit. Otherwise we are doing the wrong
5970 /* This is analogous to the code for l_const above. */
5971 if (rcode != wanted_code)
5973 if (r_const && integer_zerop (r_const) && integer_pow2p (rl_mask))
5982 /* See if we can find a mode that contains both fields being compared on
5983 the left. If we can't, fail. Otherwise, update all constants and masks
5984 to be relative to a field of that size. */
5985 first_bit = MIN (ll_bitpos, rl_bitpos);
5986 end_bit = MAX (ll_bitpos + ll_bitsize, rl_bitpos + rl_bitsize);
5987 lnmode = get_best_mode (end_bit - first_bit, first_bit,
5988 TYPE_ALIGN (TREE_TYPE (ll_inner)), word_mode,
5990 if (lnmode == VOIDmode)
5993 lnbitsize = GET_MODE_BITSIZE (lnmode);
5994 lnbitpos = first_bit & ~ (lnbitsize - 1);
5995 lntype = lang_hooks.types.type_for_size (lnbitsize, 1);
5996 xll_bitpos = ll_bitpos - lnbitpos, xrl_bitpos = rl_bitpos - lnbitpos;
5998 if (BYTES_BIG_ENDIAN)
6000 xll_bitpos = lnbitsize - xll_bitpos - ll_bitsize;
6001 xrl_bitpos = lnbitsize - xrl_bitpos - rl_bitsize;
6004 ll_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, ll_mask),
6005 size_int (xll_bitpos), 0);
6006 rl_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc, lntype, rl_mask),
6007 size_int (xrl_bitpos), 0);
6011 l_const = fold_convert_loc (loc, lntype, l_const);
6012 l_const = unextend (l_const, ll_bitsize, ll_unsignedp, ll_and_mask);
6013 l_const = const_binop (LSHIFT_EXPR, l_const, size_int (xll_bitpos), 0);
6014 if (! integer_zerop (const_binop (BIT_AND_EXPR, l_const,
6015 fold_build1_loc (loc, BIT_NOT_EXPR,
6019 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
6021 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
6026 r_const = fold_convert_loc (loc, lntype, r_const);
6027 r_const = unextend (r_const, rl_bitsize, rl_unsignedp, rl_and_mask);
6028 r_const = const_binop (LSHIFT_EXPR, r_const, size_int (xrl_bitpos), 0);
6029 if (! integer_zerop (const_binop (BIT_AND_EXPR, r_const,
6030 fold_build1_loc (loc, BIT_NOT_EXPR,
6034 warning (0, "comparison is always %d", wanted_code == NE_EXPR);
6036 return constant_boolean_node (wanted_code == NE_EXPR, truth_type);
6040 /* If the right sides are not constant, do the same for it. Also,
6041 disallow this optimization if a size or signedness mismatch occurs
6042 between the left and right sides. */
6045 if (ll_bitsize != lr_bitsize || rl_bitsize != rr_bitsize
6046 || ll_unsignedp != lr_unsignedp || rl_unsignedp != rr_unsignedp
6047 /* Make sure the two fields on the right
6048 correspond to the left without being swapped. */
6049 || ll_bitpos - rl_bitpos != lr_bitpos - rr_bitpos)
6052 first_bit = MIN (lr_bitpos, rr_bitpos);
6053 end_bit = MAX (lr_bitpos + lr_bitsize, rr_bitpos + rr_bitsize);
6054 rnmode = get_best_mode (end_bit - first_bit, first_bit,
6055 TYPE_ALIGN (TREE_TYPE (lr_inner)), word_mode,
6057 if (rnmode == VOIDmode)
6060 rnbitsize = GET_MODE_BITSIZE (rnmode);
6061 rnbitpos = first_bit & ~ (rnbitsize - 1);
6062 rntype = lang_hooks.types.type_for_size (rnbitsize, 1);
6063 xlr_bitpos = lr_bitpos - rnbitpos, xrr_bitpos = rr_bitpos - rnbitpos;
6065 if (BYTES_BIG_ENDIAN)
6067 xlr_bitpos = rnbitsize - xlr_bitpos - lr_bitsize;
6068 xrr_bitpos = rnbitsize - xrr_bitpos - rr_bitsize;
6071 lr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
6073 size_int (xlr_bitpos), 0);
6074 rr_mask = const_binop (LSHIFT_EXPR, fold_convert_loc (loc,
6076 size_int (xrr_bitpos), 0);
6078 /* Make a mask that corresponds to both fields being compared.
6079 Do this for both items being compared. If the operands are the
6080 same size and the bits being compared are in the same position
6081 then we can do this by masking both and comparing the masked
6083 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
6084 lr_mask = const_binop (BIT_IOR_EXPR, lr_mask, rr_mask, 0);
6085 if (lnbitsize == rnbitsize && xll_bitpos == xlr_bitpos)
6087 lhs = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
6088 ll_unsignedp || rl_unsignedp);
6089 if (! all_ones_mask_p (ll_mask, lnbitsize))
6090 lhs = build2 (BIT_AND_EXPR, lntype, lhs, ll_mask);
6092 rhs = make_bit_field_ref (loc, lr_inner, rntype, rnbitsize, rnbitpos,
6093 lr_unsignedp || rr_unsignedp);
6094 if (! all_ones_mask_p (lr_mask, rnbitsize))
6095 rhs = build2 (BIT_AND_EXPR, rntype, rhs, lr_mask);
6097 result = build2 (wanted_code, truth_type, lhs, rhs);
6098 goto fold_truthop_exit;
6101 /* There is still another way we can do something: If both pairs of
6102 fields being compared are adjacent, we may be able to make a wider
6103 field containing them both.
6105 Note that we still must mask the lhs/rhs expressions. Furthermore,
6106 the mask must be shifted to account for the shift done by
6107 make_bit_field_ref. */
6108 if ((ll_bitsize + ll_bitpos == rl_bitpos
6109 && lr_bitsize + lr_bitpos == rr_bitpos)
6110 || (ll_bitpos == rl_bitpos + rl_bitsize
6111 && lr_bitpos == rr_bitpos + rr_bitsize))
6115 lhs = make_bit_field_ref (loc, ll_inner, lntype,
6116 ll_bitsize + rl_bitsize,
6117 MIN (ll_bitpos, rl_bitpos), ll_unsignedp);
6118 rhs = make_bit_field_ref (loc, lr_inner, rntype,
6119 lr_bitsize + rr_bitsize,
6120 MIN (lr_bitpos, rr_bitpos), lr_unsignedp);
6122 ll_mask = const_binop (RSHIFT_EXPR, ll_mask,
6123 size_int (MIN (xll_bitpos, xrl_bitpos)), 0);
6124 lr_mask = const_binop (RSHIFT_EXPR, lr_mask,
6125 size_int (MIN (xlr_bitpos, xrr_bitpos)), 0);
6127 /* Convert to the smaller type before masking out unwanted bits. */
6129 if (lntype != rntype)
6131 if (lnbitsize > rnbitsize)
6133 lhs = fold_convert_loc (loc, rntype, lhs);
6134 ll_mask = fold_convert_loc (loc, rntype, ll_mask);
6137 else if (lnbitsize < rnbitsize)
6139 rhs = fold_convert_loc (loc, lntype, rhs);
6140 lr_mask = fold_convert_loc (loc, lntype, lr_mask);
6145 if (! all_ones_mask_p (ll_mask, ll_bitsize + rl_bitsize))
6146 lhs = build2 (BIT_AND_EXPR, type, lhs, ll_mask);
6148 if (! all_ones_mask_p (lr_mask, lr_bitsize + rr_bitsize))
6149 rhs = build2 (BIT_AND_EXPR, type, rhs, lr_mask);
6151 result = build2 (wanted_code, truth_type, lhs, rhs);
6152 goto fold_truthop_exit;
6158 /* Handle the case of comparisons with constants. If there is something in
6159 common between the masks, those bits of the constants must be the same.
6160 If not, the condition is always false. Test for this to avoid generating
6161 incorrect code below. */
6162 result = const_binop (BIT_AND_EXPR, ll_mask, rl_mask, 0);
6163 if (! integer_zerop (result)
6164 && simple_cst_equal (const_binop (BIT_AND_EXPR, result, l_const, 0),
6165 const_binop (BIT_AND_EXPR, result, r_const, 0)) != 1)
6167 if (wanted_code == NE_EXPR)
6169 warning (0, "%<or%> of unmatched not-equal tests is always 1");
6170 return constant_boolean_node (true, truth_type);
6174 warning (0, "%<and%> of mutually exclusive equal-tests is always 0");
6175 return constant_boolean_node (false, truth_type);
6179 /* Construct the expression we will return. First get the component
6180 reference we will make. Unless the mask is all ones the width of
6181 that field, perform the mask operation. Then compare with the
6183 result = make_bit_field_ref (loc, ll_inner, lntype, lnbitsize, lnbitpos,
6184 ll_unsignedp || rl_unsignedp);
6186 ll_mask = const_binop (BIT_IOR_EXPR, ll_mask, rl_mask, 0);
6187 if (! all_ones_mask_p (ll_mask, lnbitsize))
6189 result = build2 (BIT_AND_EXPR, lntype, result, ll_mask);
6190 SET_EXPR_LOCATION (result, loc);
6193 result = build2 (wanted_code, truth_type, result,
6194 const_binop (BIT_IOR_EXPR, l_const, r_const, 0));
6197 SET_EXPR_LOCATION (result, loc);
6201 /* Optimize T, which is a comparison of a MIN_EXPR or MAX_EXPR with a
6205 optimize_minmax_comparison (location_t loc, enum tree_code code, tree type,
6209 enum tree_code op_code;
6212 int consts_equal, consts_lt;
6215 STRIP_SIGN_NOPS (arg0);
6217 op_code = TREE_CODE (arg0);
6218 minmax_const = TREE_OPERAND (arg0, 1);
6219 comp_const = fold_convert_loc (loc, TREE_TYPE (arg0), op1);
6220 consts_equal = tree_int_cst_equal (minmax_const, comp_const);
6221 consts_lt = tree_int_cst_lt (minmax_const, comp_const);
6222 inner = TREE_OPERAND (arg0, 0);
6224 /* If something does not permit us to optimize, return the original tree. */
6225 if ((op_code != MIN_EXPR && op_code != MAX_EXPR)
6226 || TREE_CODE (comp_const) != INTEGER_CST
6227 || TREE_OVERFLOW (comp_const)
6228 || TREE_CODE (minmax_const) != INTEGER_CST
6229 || TREE_OVERFLOW (minmax_const))
6232 /* Now handle all the various comparison codes. We only handle EQ_EXPR
6233 and GT_EXPR, doing the rest with recursive calls using logical
6237 case NE_EXPR: case LT_EXPR: case LE_EXPR:
6240 = optimize_minmax_comparison (loc,
6241 invert_tree_comparison (code, false),
6244 return invert_truthvalue_loc (loc, tem);
6250 fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
6251 optimize_minmax_comparison
6252 (loc, EQ_EXPR, type, arg0, comp_const),
6253 optimize_minmax_comparison
6254 (loc, GT_EXPR, type, arg0, comp_const));
6257 if (op_code == MAX_EXPR && consts_equal)
6258 /* MAX (X, 0) == 0 -> X <= 0 */
6259 return fold_build2_loc (loc, LE_EXPR, type, inner, comp_const);
6261 else if (op_code == MAX_EXPR && consts_lt)
6262 /* MAX (X, 0) == 5 -> X == 5 */
6263 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
6265 else if (op_code == MAX_EXPR)
6266 /* MAX (X, 0) == -1 -> false */
6267 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6269 else if (consts_equal)
6270 /* MIN (X, 0) == 0 -> X >= 0 */
6271 return fold_build2_loc (loc, GE_EXPR, type, inner, comp_const);
6274 /* MIN (X, 0) == 5 -> false */
6275 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6278 /* MIN (X, 0) == -1 -> X == -1 */
6279 return fold_build2_loc (loc, EQ_EXPR, type, inner, comp_const);
6282 if (op_code == MAX_EXPR && (consts_equal || consts_lt))
6283 /* MAX (X, 0) > 0 -> X > 0
6284 MAX (X, 0) > 5 -> X > 5 */
6285 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
6287 else if (op_code == MAX_EXPR)
6288 /* MAX (X, 0) > -1 -> true */
6289 return omit_one_operand_loc (loc, type, integer_one_node, inner);
6291 else if (op_code == MIN_EXPR && (consts_equal || consts_lt))
6292 /* MIN (X, 0) > 0 -> false
6293 MIN (X, 0) > 5 -> false */
6294 return omit_one_operand_loc (loc, type, integer_zero_node, inner);
6297 /* MIN (X, 0) > -1 -> X > -1 */
6298 return fold_build2_loc (loc, GT_EXPR, type, inner, comp_const);
6305 /* T is an integer expression that is being multiplied, divided, or taken a
6306 modulus (CODE says which and what kind of divide or modulus) by a
6307 constant C. See if we can eliminate that operation by folding it with
6308 other operations already in T. WIDE_TYPE, if non-null, is a type that
6309 should be used for the computation if wider than our type.
6311 For example, if we are dividing (X * 8) + (Y * 16) by 4, we can return
6312 (X * 2) + (Y * 4). We must, however, be assured that either the original
6313 expression would not overflow or that overflow is undefined for the type
6314 in the language in question.
6316 If we return a non-null expression, it is an equivalent form of the
6317 original computation, but need not be in the original type.
6319 We set *STRICT_OVERFLOW_P to true if the return values depends on
6320 signed overflow being undefined. Otherwise we do not change
6321 *STRICT_OVERFLOW_P. */
6324 extract_muldiv (tree t, tree c, enum tree_code code, tree wide_type,
6325 bool *strict_overflow_p)
6327 /* To avoid exponential search depth, refuse to allow recursion past
6328 three levels. Beyond that (1) it's highly unlikely that we'll find
6329 something interesting and (2) we've probably processed it before
6330 when we built the inner expression. */
6339 ret = extract_muldiv_1 (t, c, code, wide_type, strict_overflow_p);
6346 extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
6347 bool *strict_overflow_p)
6349 tree type = TREE_TYPE (t);
6350 enum tree_code tcode = TREE_CODE (t);
6351 tree ctype = (wide_type != 0 && (GET_MODE_SIZE (TYPE_MODE (wide_type))
6352 > GET_MODE_SIZE (TYPE_MODE (type)))
6353 ? wide_type : type);
6355 int same_p = tcode == code;
6356 tree op0 = NULL_TREE, op1 = NULL_TREE;
6357 bool sub_strict_overflow_p;
6359 /* Don't deal with constants of zero here; they confuse the code below. */
6360 if (integer_zerop (c))
6363 if (TREE_CODE_CLASS (tcode) == tcc_unary)
6364 op0 = TREE_OPERAND (t, 0);
6366 if (TREE_CODE_CLASS (tcode) == tcc_binary)
6367 op0 = TREE_OPERAND (t, 0), op1 = TREE_OPERAND (t, 1);
6369 /* Note that we need not handle conditional operations here since fold
6370 already handles those cases. So just do arithmetic here. */
6374 /* For a constant, we can always simplify if we are a multiply
6375 or (for divide and modulus) if it is a multiple of our constant. */
6376 if (code == MULT_EXPR
6377 || integer_zerop (const_binop (TRUNC_MOD_EXPR, t, c, 0)))
6378 return const_binop (code, fold_convert (ctype, t),
6379 fold_convert (ctype, c), 0);
6382 CASE_CONVERT: case NON_LVALUE_EXPR:
6383 /* If op0 is an expression ... */
6384 if ((COMPARISON_CLASS_P (op0)
6385 || UNARY_CLASS_P (op0)
6386 || BINARY_CLASS_P (op0)
6387 || VL_EXP_CLASS_P (op0)
6388 || EXPRESSION_CLASS_P (op0))
6389 /* ... and has wrapping overflow, and its type is smaller
6390 than ctype, then we cannot pass through as widening. */
6391 && ((TYPE_OVERFLOW_WRAPS (TREE_TYPE (op0))
6392 && ! (TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
6393 && TYPE_IS_SIZETYPE (TREE_TYPE (op0)))
6394 && (TYPE_PRECISION (ctype)
6395 > TYPE_PRECISION (TREE_TYPE (op0))))
6396 /* ... or this is a truncation (t is narrower than op0),
6397 then we cannot pass through this narrowing. */
6398 || (TYPE_PRECISION (type)
6399 < TYPE_PRECISION (TREE_TYPE (op0)))
6400 /* ... or signedness changes for division or modulus,
6401 then we cannot pass through this conversion. */
6402 || (code != MULT_EXPR
6403 && (TYPE_UNSIGNED (ctype)
6404 != TYPE_UNSIGNED (TREE_TYPE (op0))))
6405 /* ... or has undefined overflow while the converted to
6406 type has not, we cannot do the operation in the inner type
6407 as that would introduce undefined overflow. */
6408 || (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0))
6409 && !TYPE_OVERFLOW_UNDEFINED (type))))
6412 /* Pass the constant down and see if we can make a simplification. If
6413 we can, replace this expression with the inner simplification for
6414 possible later conversion to our or some other type. */
6415 if ((t2 = fold_convert (TREE_TYPE (op0), c)) != 0
6416 && TREE_CODE (t2) == INTEGER_CST
6417 && !TREE_OVERFLOW (t2)
6418 && (0 != (t1 = extract_muldiv (op0, t2, code,
6420 ? ctype : NULL_TREE,
6421 strict_overflow_p))))
6426 /* If widening the type changes it from signed to unsigned, then we
6427 must avoid building ABS_EXPR itself as unsigned. */
6428 if (TYPE_UNSIGNED (ctype) && !TYPE_UNSIGNED (type))
6430 tree cstype = (*signed_type_for) (ctype);
6431 if ((t1 = extract_muldiv (op0, c, code, cstype, strict_overflow_p))
6434 t1 = fold_build1 (tcode, cstype, fold_convert (cstype, t1));
6435 return fold_convert (ctype, t1);
6439 /* If the constant is negative, we cannot simplify this. */
6440 if (tree_int_cst_sgn (c) == -1)
6444 if ((t1 = extract_muldiv (op0, c, code, wide_type, strict_overflow_p))
6446 return fold_build1 (tcode, ctype, fold_convert (ctype, t1));
6449 case MIN_EXPR: case MAX_EXPR:
6450 /* If widening the type changes the signedness, then we can't perform
6451 this optimization as that changes the result. */
6452 if (TYPE_UNSIGNED (ctype) != TYPE_UNSIGNED (type))
6455 /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
6456 sub_strict_overflow_p = false;
6457 if ((t1 = extract_muldiv (op0, c, code, wide_type,
6458 &sub_strict_overflow_p)) != 0
6459 && (t2 = extract_muldiv (op1, c, code, wide_type,
6460 &sub_strict_overflow_p)) != 0)
6462 if (tree_int_cst_sgn (c) < 0)
6463 tcode = (tcode == MIN_EXPR ? MAX_EXPR : MIN_EXPR);
6464 if (sub_strict_overflow_p)
6465 *strict_overflow_p = true;
6466 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6467 fold_convert (ctype, t2));
6471 case LSHIFT_EXPR: case RSHIFT_EXPR:
6472 /* If the second operand is constant, this is a multiplication
6473 or floor division, by a power of two, so we can treat it that
6474 way unless the multiplier or divisor overflows. Signed
6475 left-shift overflow is implementation-defined rather than
6476 undefined in C90, so do not convert signed left shift into
6478 if (TREE_CODE (op1) == INTEGER_CST
6479 && (tcode == RSHIFT_EXPR || TYPE_UNSIGNED (TREE_TYPE (op0)))
6480 /* const_binop may not detect overflow correctly,
6481 so check for it explicitly here. */
6482 && TYPE_PRECISION (TREE_TYPE (size_one_node)) > TREE_INT_CST_LOW (op1)
6483 && TREE_INT_CST_HIGH (op1) == 0
6484 && 0 != (t1 = fold_convert (ctype,
6485 const_binop (LSHIFT_EXPR,
6488 && !TREE_OVERFLOW (t1))
6489 return extract_muldiv (build2 (tcode == LSHIFT_EXPR
6490 ? MULT_EXPR : FLOOR_DIV_EXPR,
6492 fold_convert (ctype, op0),
6494 c, code, wide_type, strict_overflow_p);
6497 case PLUS_EXPR: case MINUS_EXPR:
6498 /* See if we can eliminate the operation on both sides. If we can, we
6499 can return a new PLUS or MINUS. If we can't, the only remaining
6500 cases where we can do anything are if the second operand is a
6502 sub_strict_overflow_p = false;
6503 t1 = extract_muldiv (op0, c, code, wide_type, &sub_strict_overflow_p);
6504 t2 = extract_muldiv (op1, c, code, wide_type, &sub_strict_overflow_p);
6505 if (t1 != 0 && t2 != 0
6506 && (code == MULT_EXPR
6507 /* If not multiplication, we can only do this if both operands
6508 are divisible by c. */
6509 || (multiple_of_p (ctype, op0, c)
6510 && multiple_of_p (ctype, op1, c))))
6512 if (sub_strict_overflow_p)
6513 *strict_overflow_p = true;
6514 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6515 fold_convert (ctype, t2));
6518 /* If this was a subtraction, negate OP1 and set it to be an addition.
6519 This simplifies the logic below. */
6520 if (tcode == MINUS_EXPR)
6522 tcode = PLUS_EXPR, op1 = negate_expr (op1);
6523 /* If OP1 was not easily negatable, the constant may be OP0. */
6524 if (TREE_CODE (op0) == INTEGER_CST)
6535 if (TREE_CODE (op1) != INTEGER_CST)
6538 /* If either OP1 or C are negative, this optimization is not safe for
6539 some of the division and remainder types while for others we need
6540 to change the code. */
6541 if (tree_int_cst_sgn (op1) < 0 || tree_int_cst_sgn (c) < 0)
6543 if (code == CEIL_DIV_EXPR)
6544 code = FLOOR_DIV_EXPR;
6545 else if (code == FLOOR_DIV_EXPR)
6546 code = CEIL_DIV_EXPR;
6547 else if (code != MULT_EXPR
6548 && code != CEIL_MOD_EXPR && code != FLOOR_MOD_EXPR)
6552 /* If it's a multiply or a division/modulus operation of a multiple
6553 of our constant, do the operation and verify it doesn't overflow. */
6554 if (code == MULT_EXPR
6555 || integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6557 op1 = const_binop (code, fold_convert (ctype, op1),
6558 fold_convert (ctype, c), 0);
6559 /* We allow the constant to overflow with wrapping semantics. */
6561 || (TREE_OVERFLOW (op1) && !TYPE_OVERFLOW_WRAPS (ctype)))
6567 /* If we have an unsigned type is not a sizetype, we cannot widen
6568 the operation since it will change the result if the original
6569 computation overflowed. */
6570 if (TYPE_UNSIGNED (ctype)
6571 && ! (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype))
6575 /* If we were able to eliminate our operation from the first side,
6576 apply our operation to the second side and reform the PLUS. */
6577 if (t1 != 0 && (TREE_CODE (t1) != code || code == MULT_EXPR))
6578 return fold_build2 (tcode, ctype, fold_convert (ctype, t1), op1);
6580 /* The last case is if we are a multiply. In that case, we can
6581 apply the distributive law to commute the multiply and addition
6582 if the multiplication of the constants doesn't overflow. */
6583 if (code == MULT_EXPR)
6584 return fold_build2 (tcode, ctype,
6585 fold_build2 (code, ctype,
6586 fold_convert (ctype, op0),
6587 fold_convert (ctype, c)),
6593 /* We have a special case here if we are doing something like
6594 (C * 8) % 4 since we know that's zero. */
6595 if ((code == TRUNC_MOD_EXPR || code == CEIL_MOD_EXPR
6596 || code == FLOOR_MOD_EXPR || code == ROUND_MOD_EXPR)
6597 /* If the multiplication can overflow we cannot optimize this.
6598 ??? Until we can properly mark individual operations as
6599 not overflowing we need to treat sizetype special here as
6600 stor-layout relies on this opimization to make
6601 DECL_FIELD_BIT_OFFSET always a constant. */
6602 && (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (t))
6603 || (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
6604 && TYPE_IS_SIZETYPE (TREE_TYPE (t))))
6605 && TREE_CODE (TREE_OPERAND (t, 1)) == INTEGER_CST
6606 && integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6608 *strict_overflow_p = true;
6609 return omit_one_operand (type, integer_zero_node, op0);
6612 /* ... fall through ... */
6614 case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR:
6615 case ROUND_DIV_EXPR: case EXACT_DIV_EXPR:
6616 /* If we can extract our operation from the LHS, do so and return a
6617 new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
6618 do something only if the second operand is a constant. */
6620 && (t1 = extract_muldiv (op0, c, code, wide_type,
6621 strict_overflow_p)) != 0)
6622 return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
6623 fold_convert (ctype, op1));
6624 else if (tcode == MULT_EXPR && code == MULT_EXPR
6625 && (t1 = extract_muldiv (op1, c, code, wide_type,
6626 strict_overflow_p)) != 0)
6627 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6628 fold_convert (ctype, t1));
6629 else if (TREE_CODE (op1) != INTEGER_CST)
6632 /* If these are the same operation types, we can associate them
6633 assuming no overflow. */
6635 && 0 != (t1 = int_const_binop (MULT_EXPR,
6636 fold_convert (ctype, op1),
6637 fold_convert (ctype, c), 1))
6638 && 0 != (t1 = force_fit_type_double (ctype, TREE_INT_CST_LOW (t1),
6639 TREE_INT_CST_HIGH (t1),
6640 (TYPE_UNSIGNED (ctype)
6641 && tcode != MULT_EXPR) ? -1 : 1,
6642 TREE_OVERFLOW (t1)))
6643 && !TREE_OVERFLOW (t1))
6644 return fold_build2 (tcode, ctype, fold_convert (ctype, op0), t1);
6646 /* If these operations "cancel" each other, we have the main
6647 optimizations of this pass, which occur when either constant is a
6648 multiple of the other, in which case we replace this with either an
6649 operation or CODE or TCODE.
6651 If we have an unsigned type that is not a sizetype, we cannot do
6652 this since it will change the result if the original computation
6654 if ((TYPE_OVERFLOW_UNDEFINED (ctype)
6655 || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
6656 && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
6657 || (tcode == MULT_EXPR
6658 && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR
6659 && code != FLOOR_MOD_EXPR && code != ROUND_MOD_EXPR
6660 && code != MULT_EXPR)))
6662 if (integer_zerop (const_binop (TRUNC_MOD_EXPR, op1, c, 0)))
6664 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6665 *strict_overflow_p = true;
6666 return fold_build2 (tcode, ctype, fold_convert (ctype, op0),
6667 fold_convert (ctype,
6668 const_binop (TRUNC_DIV_EXPR,
6671 else if (integer_zerop (const_binop (TRUNC_MOD_EXPR, c, op1, 0)))
6673 if (TYPE_OVERFLOW_UNDEFINED (ctype))
6674 *strict_overflow_p = true;
6675 return fold_build2 (code, ctype, fold_convert (ctype, op0),
6676 fold_convert (ctype,
6677 const_binop (TRUNC_DIV_EXPR,
6690 /* Return a node which has the indicated constant VALUE (either 0 or
6691 1), and is of the indicated TYPE. */
6694 constant_boolean_node (int value, tree type)
6696 if (type == integer_type_node)
6697 return value ? integer_one_node : integer_zero_node;
6698 else if (type == boolean_type_node)
6699 return value ? boolean_true_node : boolean_false_node;
6701 return build_int_cst (type, value);
6705 /* Transform `a + (b ? x : y)' into `b ? (a + x) : (a + y)'.
6706 Transform, `a + (x < y)' into `(x < y) ? (a + 1) : (a + 0)'. Here
6707 CODE corresponds to the `+', COND to the `(b ? x : y)' or `(x < y)'
6708 expression, and ARG to `a'. If COND_FIRST_P is nonzero, then the
6709 COND is the first argument to CODE; otherwise (as in the example
6710 given here), it is the second argument. TYPE is the type of the
6711 original expression. Return NULL_TREE if no simplification is
6715 fold_binary_op_with_conditional_arg (location_t loc,
6716 enum tree_code code,
6717 tree type, tree op0, tree op1,
6718 tree cond, tree arg, int cond_first_p)
6720 tree cond_type = cond_first_p ? TREE_TYPE (op0) : TREE_TYPE (op1);
6721 tree arg_type = cond_first_p ? TREE_TYPE (op1) : TREE_TYPE (op0);
6722 tree test, true_value, false_value;
6723 tree lhs = NULL_TREE;
6724 tree rhs = NULL_TREE;
6726 /* This transformation is only worthwhile if we don't have to wrap
6727 arg in a SAVE_EXPR, and the operation can be simplified on at least
6728 one of the branches once its pushed inside the COND_EXPR. */
6729 if (!TREE_CONSTANT (arg))
6732 if (TREE_CODE (cond) == COND_EXPR)
6734 test = TREE_OPERAND (cond, 0);
6735 true_value = TREE_OPERAND (cond, 1);
6736 false_value = TREE_OPERAND (cond, 2);
6737 /* If this operand throws an expression, then it does not make
6738 sense to try to perform a logical or arithmetic operation
6740 if (VOID_TYPE_P (TREE_TYPE (true_value)))
6742 if (VOID_TYPE_P (TREE_TYPE (false_value)))
6747 tree testtype = TREE_TYPE (cond);
6749 true_value = constant_boolean_node (true, testtype);
6750 false_value = constant_boolean_node (false, testtype);
6753 arg = fold_convert_loc (loc, arg_type, arg);
6756 true_value = fold_convert_loc (loc, cond_type, true_value);
6758 lhs = fold_build2_loc (loc, code, type, true_value, arg);
6760 lhs = fold_build2_loc (loc, code, type, arg, true_value);
6764 false_value = fold_convert_loc (loc, cond_type, false_value);
6766 rhs = fold_build2_loc (loc, code, type, false_value, arg);
6768 rhs = fold_build2_loc (loc, code, type, arg, false_value);
6771 test = fold_build3_loc (loc, COND_EXPR, type, test, lhs, rhs);
6772 return fold_convert_loc (loc, type, test);
6776 /* Subroutine of fold() that checks for the addition of +/- 0.0.
6778 If !NEGATE, return true if ADDEND is +/-0.0 and, for all X of type
6779 TYPE, X + ADDEND is the same as X. If NEGATE, return true if X -
6780 ADDEND is the same as X.
6782 X + 0 and X - 0 both give X when X is NaN, infinite, or nonzero
6783 and finite. The problematic cases are when X is zero, and its mode
6784 has signed zeros. In the case of rounding towards -infinity,
6785 X - 0 is not the same as X because 0 - 0 is -0. In other rounding
6786 modes, X + 0 is not the same as X because -0 + 0 is 0. */
6789 fold_real_zero_addition_p (const_tree type, const_tree addend, int negate)
6791 if (!real_zerop (addend))
6794 /* Don't allow the fold with -fsignaling-nans. */
6795 if (HONOR_SNANS (TYPE_MODE (type)))
6798 /* Allow the fold if zeros aren't signed, or their sign isn't important. */
6799 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
6802 /* Treat x + -0 as x - 0 and x - -0 as x + 0. */
6803 if (TREE_CODE (addend) == REAL_CST
6804 && REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (addend)))
6807 /* The mode has signed zeros, and we have to honor their sign.
6808 In this situation, there is only one case we can return true for.
6809 X - 0 is the same as X unless rounding towards -infinity is
6811 return negate && !HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (type));
6814 /* Subroutine of fold() that checks comparisons of built-in math
6815 functions against real constants.
6817 FCODE is the DECL_FUNCTION_CODE of the built-in, CODE is the comparison
6818 operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR, GE_EXPR or LE_EXPR. TYPE
6819 is the type of the result and ARG0 and ARG1 are the operands of the
6820 comparison. ARG1 must be a TREE_REAL_CST.
6822 The function returns the constant folded tree if a simplification
6823 can be made, and NULL_TREE otherwise. */
6826 fold_mathfn_compare (location_t loc,
6827 enum built_in_function fcode, enum tree_code code,
6828 tree type, tree arg0, tree arg1)
6832 if (BUILTIN_SQRT_P (fcode))
6834 tree arg = CALL_EXPR_ARG (arg0, 0);
6835 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg0));
6837 c = TREE_REAL_CST (arg1);
6838 if (REAL_VALUE_NEGATIVE (c))
6840 /* sqrt(x) < y is always false, if y is negative. */
6841 if (code == EQ_EXPR || code == LT_EXPR || code == LE_EXPR)
6842 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6844 /* sqrt(x) > y is always true, if y is negative and we
6845 don't care about NaNs, i.e. negative values of x. */
6846 if (code == NE_EXPR || !HONOR_NANS (mode))
6847 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6849 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
6850 return fold_build2_loc (loc, GE_EXPR, type, arg,
6851 build_real (TREE_TYPE (arg), dconst0));
6853 else if (code == GT_EXPR || code == GE_EXPR)
6857 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6858 real_convert (&c2, mode, &c2);
6860 if (REAL_VALUE_ISINF (c2))
6862 /* sqrt(x) > y is x == +Inf, when y is very large. */
6863 if (HONOR_INFINITIES (mode))
6864 return fold_build2_loc (loc, EQ_EXPR, type, arg,
6865 build_real (TREE_TYPE (arg), c2));
6867 /* sqrt(x) > y is always false, when y is very large
6868 and we don't care about infinities. */
6869 return omit_one_operand_loc (loc, type, integer_zero_node, arg);
6872 /* sqrt(x) > c is the same as x > c*c. */
6873 return fold_build2_loc (loc, code, type, arg,
6874 build_real (TREE_TYPE (arg), c2));
6876 else if (code == LT_EXPR || code == LE_EXPR)
6880 REAL_ARITHMETIC (c2, MULT_EXPR, c, c);
6881 real_convert (&c2, mode, &c2);
6883 if (REAL_VALUE_ISINF (c2))
6885 /* sqrt(x) < y is always true, when y is a very large
6886 value and we don't care about NaNs or Infinities. */
6887 if (! HONOR_NANS (mode) && ! HONOR_INFINITIES (mode))
6888 return omit_one_operand_loc (loc, type, integer_one_node, arg);
6890 /* sqrt(x) < y is x != +Inf when y is very large and we
6891 don't care about NaNs. */
6892 if (! HONOR_NANS (mode))
6893 return fold_build2_loc (loc, NE_EXPR, type, arg,
6894 build_real (TREE_TYPE (arg), c2));
6896 /* sqrt(x) < y is x >= 0 when y is very large and we
6897 don't care about Infinities. */
6898 if (! HONOR_INFINITIES (mode))
6899 return fold_build2_loc (loc, GE_EXPR, type, arg,
6900 build_real (TREE_TYPE (arg), dconst0));
6902 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
6903 if (lang_hooks.decls.global_bindings_p () != 0
6904 || CONTAINS_PLACEHOLDER_P (arg))
6907 arg = save_expr (arg);
6908 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6909 fold_build2_loc (loc, GE_EXPR, type, arg,
6910 build_real (TREE_TYPE (arg),
6912 fold_build2_loc (loc, NE_EXPR, type, arg,
6913 build_real (TREE_TYPE (arg),
6917 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
6918 if (! HONOR_NANS (mode))
6919 return fold_build2_loc (loc, code, type, arg,
6920 build_real (TREE_TYPE (arg), c2));
6922 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
6923 if (lang_hooks.decls.global_bindings_p () == 0
6924 && ! CONTAINS_PLACEHOLDER_P (arg))
6926 arg = save_expr (arg);
6927 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
6928 fold_build2_loc (loc, GE_EXPR, type, arg,
6929 build_real (TREE_TYPE (arg),
6931 fold_build2_loc (loc, code, type, arg,
6932 build_real (TREE_TYPE (arg),
6941 /* Subroutine of fold() that optimizes comparisons against Infinities,
6942 either +Inf or -Inf.
6944 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
6945 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
6946 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
6948 The function returns the constant folded tree if a simplification
6949 can be made, and NULL_TREE otherwise. */
6952 fold_inf_compare (location_t loc, enum tree_code code, tree type,
6953 tree arg0, tree arg1)
6955 enum machine_mode mode;
6956 REAL_VALUE_TYPE max;
6960 mode = TYPE_MODE (TREE_TYPE (arg0));
6962 /* For negative infinity swap the sense of the comparison. */
6963 neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1));
6965 code = swap_tree_comparison (code);
6970 /* x > +Inf is always false, if with ignore sNANs. */
6971 if (HONOR_SNANS (mode))
6973 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
6976 /* x <= +Inf is always true, if we don't case about NaNs. */
6977 if (! HONOR_NANS (mode))
6978 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
6980 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
6981 if (lang_hooks.decls.global_bindings_p () == 0
6982 && ! CONTAINS_PLACEHOLDER_P (arg0))
6984 arg0 = save_expr (arg0);
6985 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg0);
6991 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
6992 real_maxval (&max, neg, mode);
6993 return fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
6994 arg0, build_real (TREE_TYPE (arg0), max));
6997 /* x < +Inf is always equal to x <= DBL_MAX. */
6998 real_maxval (&max, neg, mode);
6999 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
7000 arg0, build_real (TREE_TYPE (arg0), max));
7003 /* x != +Inf is always equal to !(x > DBL_MAX). */
7004 real_maxval (&max, neg, mode);
7005 if (! HONOR_NANS (mode))
7006 return fold_build2_loc (loc, neg ? GE_EXPR : LE_EXPR, type,
7007 arg0, build_real (TREE_TYPE (arg0), max));
7009 temp = fold_build2_loc (loc, neg ? LT_EXPR : GT_EXPR, type,
7010 arg0, build_real (TREE_TYPE (arg0), max));
7011 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type, temp);
7020 /* Subroutine of fold() that optimizes comparisons of a division by
7021 a nonzero integer constant against an integer constant, i.e.
7024 CODE is the comparison operator: EQ_EXPR, NE_EXPR, GT_EXPR, LT_EXPR,
7025 GE_EXPR or LE_EXPR. TYPE is the type of the result and ARG0 and ARG1
7026 are the operands of the comparison. ARG1 must be a TREE_REAL_CST.
7028 The function returns the constant folded tree if a simplification
7029 can be made, and NULL_TREE otherwise. */
7032 fold_div_compare (location_t loc,
7033 enum tree_code code, tree type, tree arg0, tree arg1)
7035 tree prod, tmp, hi, lo;
7036 tree arg00 = TREE_OPERAND (arg0, 0);
7037 tree arg01 = TREE_OPERAND (arg0, 1);
7038 unsigned HOST_WIDE_INT lpart;
7039 HOST_WIDE_INT hpart;
7040 bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (arg0));
7044 /* We have to do this the hard way to detect unsigned overflow.
7045 prod = int_const_binop (MULT_EXPR, arg01, arg1, 0); */
7046 overflow = mul_double_with_sign (TREE_INT_CST_LOW (arg01),
7047 TREE_INT_CST_HIGH (arg01),
7048 TREE_INT_CST_LOW (arg1),
7049 TREE_INT_CST_HIGH (arg1),
7050 &lpart, &hpart, unsigned_p);
7051 prod = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
7053 neg_overflow = false;
7057 tmp = int_const_binop (MINUS_EXPR, arg01,
7058 build_int_cst (TREE_TYPE (arg01), 1), 0);
7061 /* Likewise hi = int_const_binop (PLUS_EXPR, prod, tmp, 0). */
7062 overflow = add_double_with_sign (TREE_INT_CST_LOW (prod),
7063 TREE_INT_CST_HIGH (prod),
7064 TREE_INT_CST_LOW (tmp),
7065 TREE_INT_CST_HIGH (tmp),
7066 &lpart, &hpart, unsigned_p);
7067 hi = force_fit_type_double (TREE_TYPE (arg00), lpart, hpart,
7068 -1, overflow | TREE_OVERFLOW (prod));
7070 else if (tree_int_cst_sgn (arg01) >= 0)
7072 tmp = int_const_binop (MINUS_EXPR, arg01,
7073 build_int_cst (TREE_TYPE (arg01), 1), 0);
7074 switch (tree_int_cst_sgn (arg1))
7077 neg_overflow = true;
7078 lo = int_const_binop (MINUS_EXPR, prod, tmp, 0);
7083 lo = fold_negate_const (tmp, TREE_TYPE (arg0));
7088 hi = int_const_binop (PLUS_EXPR, prod, tmp, 0);
7098 /* A negative divisor reverses the relational operators. */
7099 code = swap_tree_comparison (code);
7101 tmp = int_const_binop (PLUS_EXPR, arg01,
7102 build_int_cst (TREE_TYPE (arg01), 1), 0);
7103 switch (tree_int_cst_sgn (arg1))
7106 hi = int_const_binop (MINUS_EXPR, prod, tmp, 0);
7111 hi = fold_negate_const (tmp, TREE_TYPE (arg0));
7116 neg_overflow = true;
7117 lo = int_const_binop (PLUS_EXPR, prod, tmp, 0);
7129 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
7130 return omit_one_operand_loc (loc, type, integer_zero_node, arg00);
7131 if (TREE_OVERFLOW (hi))
7132 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
7133 if (TREE_OVERFLOW (lo))
7134 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
7135 return build_range_check (loc, type, arg00, 1, lo, hi);
7138 if (TREE_OVERFLOW (lo) && TREE_OVERFLOW (hi))
7139 return omit_one_operand_loc (loc, type, integer_one_node, arg00);
7140 if (TREE_OVERFLOW (hi))
7141 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
7142 if (TREE_OVERFLOW (lo))
7143 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
7144 return build_range_check (loc, type, arg00, 0, lo, hi);
7147 if (TREE_OVERFLOW (lo))
7149 tmp = neg_overflow ? integer_zero_node : integer_one_node;
7150 return omit_one_operand_loc (loc, type, tmp, arg00);
7152 return fold_build2_loc (loc, LT_EXPR, type, arg00, lo);
7155 if (TREE_OVERFLOW (hi))
7157 tmp = neg_overflow ? integer_zero_node : integer_one_node;
7158 return omit_one_operand_loc (loc, type, tmp, arg00);
7160 return fold_build2_loc (loc, LE_EXPR, type, arg00, hi);
7163 if (TREE_OVERFLOW (hi))
7165 tmp = neg_overflow ? integer_one_node : integer_zero_node;
7166 return omit_one_operand_loc (loc, type, tmp, arg00);
7168 return fold_build2_loc (loc, GT_EXPR, type, arg00, hi);
7171 if (TREE_OVERFLOW (lo))
7173 tmp = neg_overflow ? integer_one_node : integer_zero_node;
7174 return omit_one_operand_loc (loc, type, tmp, arg00);
7176 return fold_build2_loc (loc, GE_EXPR, type, arg00, lo);
7186 /* If CODE with arguments ARG0 and ARG1 represents a single bit
7187 equality/inequality test, then return a simplified form of the test
7188 using a sign testing. Otherwise return NULL. TYPE is the desired
7192 fold_single_bit_test_into_sign_test (location_t loc,
7193 enum tree_code code, tree arg0, tree arg1,
7196 /* If this is testing a single bit, we can optimize the test. */
7197 if ((code == NE_EXPR || code == EQ_EXPR)
7198 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
7199 && integer_pow2p (TREE_OPERAND (arg0, 1)))
7201 /* If we have (A & C) != 0 where C is the sign bit of A, convert
7202 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
7203 tree arg00 = sign_bit_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
7205 if (arg00 != NULL_TREE
7206 /* This is only a win if casting to a signed type is cheap,
7207 i.e. when arg00's type is not a partial mode. */
7208 && TYPE_PRECISION (TREE_TYPE (arg00))
7209 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg00))))
7211 tree stype = signed_type_for (TREE_TYPE (arg00));
7212 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
7214 fold_convert_loc (loc, stype, arg00),
7215 build_int_cst (stype, 0));
7222 /* If CODE with arguments ARG0 and ARG1 represents a single bit
7223 equality/inequality test, then return a simplified form of
7224 the test using shifts and logical operations. Otherwise return
7225 NULL. TYPE is the desired result type. */
7228 fold_single_bit_test (location_t loc, enum tree_code code,
7229 tree arg0, tree arg1, tree result_type)
7231 /* If this is testing a single bit, we can optimize the test. */
7232 if ((code == NE_EXPR || code == EQ_EXPR)
7233 && TREE_CODE (arg0) == BIT_AND_EXPR && integer_zerop (arg1)
7234 && integer_pow2p (TREE_OPERAND (arg0, 1)))
7236 tree inner = TREE_OPERAND (arg0, 0);
7237 tree type = TREE_TYPE (arg0);
7238 int bitnum = tree_log2 (TREE_OPERAND (arg0, 1));
7239 enum machine_mode operand_mode = TYPE_MODE (type);
7241 tree signed_type, unsigned_type, intermediate_type;
7244 /* First, see if we can fold the single bit test into a sign-bit
7246 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1,
7251 /* Otherwise we have (A & C) != 0 where C is a single bit,
7252 convert that into ((A >> C2) & 1). Where C2 = log2(C).
7253 Similarly for (A & C) == 0. */
7255 /* If INNER is a right shift of a constant and it plus BITNUM does
7256 not overflow, adjust BITNUM and INNER. */
7257 if (TREE_CODE (inner) == RSHIFT_EXPR
7258 && TREE_CODE (TREE_OPERAND (inner, 1)) == INTEGER_CST
7259 && TREE_INT_CST_HIGH (TREE_OPERAND (inner, 1)) == 0
7260 && bitnum < TYPE_PRECISION (type)
7261 && 0 > compare_tree_int (TREE_OPERAND (inner, 1),
7262 bitnum - TYPE_PRECISION (type)))
7264 bitnum += TREE_INT_CST_LOW (TREE_OPERAND (inner, 1));
7265 inner = TREE_OPERAND (inner, 0);
7268 /* If we are going to be able to omit the AND below, we must do our
7269 operations as unsigned. If we must use the AND, we have a choice.
7270 Normally unsigned is faster, but for some machines signed is. */
7271 #ifdef LOAD_EXTEND_OP
7272 ops_unsigned = (LOAD_EXTEND_OP (operand_mode) == SIGN_EXTEND
7273 && !flag_syntax_only) ? 0 : 1;
7278 signed_type = lang_hooks.types.type_for_mode (operand_mode, 0);
7279 unsigned_type = lang_hooks.types.type_for_mode (operand_mode, 1);
7280 intermediate_type = ops_unsigned ? unsigned_type : signed_type;
7281 inner = fold_convert_loc (loc, intermediate_type, inner);
7284 inner = build2 (RSHIFT_EXPR, intermediate_type,
7285 inner, size_int (bitnum));
7287 one = build_int_cst (intermediate_type, 1);
7289 if (code == EQ_EXPR)
7290 inner = fold_build2_loc (loc, BIT_XOR_EXPR, intermediate_type, inner, one);
7292 /* Put the AND last so it can combine with more things. */
7293 inner = build2 (BIT_AND_EXPR, intermediate_type, inner, one);
7295 /* Make sure to return the proper type. */
7296 inner = fold_convert_loc (loc, result_type, inner);
7303 /* Check whether we are allowed to reorder operands arg0 and arg1,
7304 such that the evaluation of arg1 occurs before arg0. */
7307 reorder_operands_p (const_tree arg0, const_tree arg1)
7309 if (! flag_evaluation_order)
7311 if (TREE_CONSTANT (arg0) || TREE_CONSTANT (arg1))
7313 return ! TREE_SIDE_EFFECTS (arg0)
7314 && ! TREE_SIDE_EFFECTS (arg1);
7317 /* Test whether it is preferable two swap two operands, ARG0 and
7318 ARG1, for example because ARG0 is an integer constant and ARG1
7319 isn't. If REORDER is true, only recommend swapping if we can
7320 evaluate the operands in reverse order. */
7323 tree_swap_operands_p (const_tree arg0, const_tree arg1, bool reorder)
7325 STRIP_SIGN_NOPS (arg0);
7326 STRIP_SIGN_NOPS (arg1);
7328 if (TREE_CODE (arg1) == INTEGER_CST)
7330 if (TREE_CODE (arg0) == INTEGER_CST)
7333 if (TREE_CODE (arg1) == REAL_CST)
7335 if (TREE_CODE (arg0) == REAL_CST)
7338 if (TREE_CODE (arg1) == FIXED_CST)
7340 if (TREE_CODE (arg0) == FIXED_CST)
7343 if (TREE_CODE (arg1) == COMPLEX_CST)
7345 if (TREE_CODE (arg0) == COMPLEX_CST)
7348 if (TREE_CONSTANT (arg1))
7350 if (TREE_CONSTANT (arg0))
7353 if (optimize_function_for_size_p (cfun))
7356 if (reorder && flag_evaluation_order
7357 && (TREE_SIDE_EFFECTS (arg0) || TREE_SIDE_EFFECTS (arg1)))
7360 /* It is preferable to swap two SSA_NAME to ensure a canonical form
7361 for commutative and comparison operators. Ensuring a canonical
7362 form allows the optimizers to find additional redundancies without
7363 having to explicitly check for both orderings. */
7364 if (TREE_CODE (arg0) == SSA_NAME
7365 && TREE_CODE (arg1) == SSA_NAME
7366 && SSA_NAME_VERSION (arg0) > SSA_NAME_VERSION (arg1))
7369 /* Put SSA_NAMEs last. */
7370 if (TREE_CODE (arg1) == SSA_NAME)
7372 if (TREE_CODE (arg0) == SSA_NAME)
7375 /* Put variables last. */
7384 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where
7385 ARG0 is extended to a wider type. */
7388 fold_widened_comparison (location_t loc, enum tree_code code,
7389 tree type, tree arg0, tree arg1)
7391 tree arg0_unw = get_unwidened (arg0, NULL_TREE);
7393 tree shorter_type, outer_type;
7397 if (arg0_unw == arg0)
7399 shorter_type = TREE_TYPE (arg0_unw);
7401 #ifdef HAVE_canonicalize_funcptr_for_compare
7402 /* Disable this optimization if we're casting a function pointer
7403 type on targets that require function pointer canonicalization. */
7404 if (HAVE_canonicalize_funcptr_for_compare
7405 && TREE_CODE (shorter_type) == POINTER_TYPE
7406 && TREE_CODE (TREE_TYPE (shorter_type)) == FUNCTION_TYPE)
7410 if (TYPE_PRECISION (TREE_TYPE (arg0)) <= TYPE_PRECISION (shorter_type))
7413 arg1_unw = get_unwidened (arg1, NULL_TREE);
7415 /* If possible, express the comparison in the shorter mode. */
7416 if ((code == EQ_EXPR || code == NE_EXPR
7417 || TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
7418 && (TREE_TYPE (arg1_unw) == shorter_type
7419 || ((TYPE_PRECISION (shorter_type)
7420 >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
7421 && (TYPE_UNSIGNED (shorter_type)
7422 == TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
7423 || (TREE_CODE (arg1_unw) == INTEGER_CST
7424 && (TREE_CODE (shorter_type) == INTEGER_TYPE
7425 || TREE_CODE (shorter_type) == BOOLEAN_TYPE)
7426 && int_fits_type_p (arg1_unw, shorter_type))))
7427 return fold_build2_loc (loc, code, type, arg0_unw,
7428 fold_convert_loc (loc, shorter_type, arg1_unw));
7430 if (TREE_CODE (arg1_unw) != INTEGER_CST
7431 || TREE_CODE (shorter_type) != INTEGER_TYPE
7432 || !int_fits_type_p (arg1_unw, shorter_type))
7435 /* If we are comparing with the integer that does not fit into the range
7436 of the shorter type, the result is known. */
7437 outer_type = TREE_TYPE (arg1_unw);
7438 min = lower_bound_in_type (outer_type, shorter_type);
7439 max = upper_bound_in_type (outer_type, shorter_type);
7441 above = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7443 below = integer_nonzerop (fold_relational_const (LT_EXPR, type,
7450 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7455 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7461 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7463 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7468 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
7470 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
7479 /* Fold comparison ARG0 CODE ARG1 (with result in TYPE), where for
7480 ARG0 just the signedness is changed. */
7483 fold_sign_changed_comparison (location_t loc, enum tree_code code, tree type,
7484 tree arg0, tree arg1)
7487 tree inner_type, outer_type;
7489 if (!CONVERT_EXPR_P (arg0))
7492 outer_type = TREE_TYPE (arg0);
7493 arg0_inner = TREE_OPERAND (arg0, 0);
7494 inner_type = TREE_TYPE (arg0_inner);
7496 #ifdef HAVE_canonicalize_funcptr_for_compare
7497 /* Disable this optimization if we're casting a function pointer
7498 type on targets that require function pointer canonicalization. */
7499 if (HAVE_canonicalize_funcptr_for_compare
7500 && TREE_CODE (inner_type) == POINTER_TYPE
7501 && TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE)
7505 if (TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type))
7508 if (TREE_CODE (arg1) != INTEGER_CST
7509 && !(CONVERT_EXPR_P (arg1)
7510 && TREE_TYPE (TREE_OPERAND (arg1, 0)) == inner_type))
7513 if ((TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type)
7514 || POINTER_TYPE_P (inner_type) != POINTER_TYPE_P (outer_type))
7519 if (TREE_CODE (arg1) == INTEGER_CST)
7520 arg1 = force_fit_type_double (inner_type, TREE_INT_CST_LOW (arg1),
7521 TREE_INT_CST_HIGH (arg1), 0,
7522 TREE_OVERFLOW (arg1));
7524 arg1 = fold_convert_loc (loc, inner_type, arg1);
7526 return fold_build2_loc (loc, code, type, arg0_inner, arg1);
7529 /* Tries to replace &a[idx] p+ s * delta with &a[idx + delta], if s is
7530 step of the array. Reconstructs s and delta in the case of s *
7531 delta being an integer constant (and thus already folded). ADDR is
7532 the address. MULT is the multiplicative expression. If the
7533 function succeeds, the new address expression is returned.
7534 Otherwise NULL_TREE is returned. LOC is the location of the
7535 resulting expression. */
7538 try_move_mult_to_index (location_t loc, tree addr, tree op1)
7540 tree s, delta, step;
7541 tree ref = TREE_OPERAND (addr, 0), pref;
7546 /* Strip the nops that might be added when converting op1 to sizetype. */
7549 /* Canonicalize op1 into a possibly non-constant delta
7550 and an INTEGER_CST s. */
7551 if (TREE_CODE (op1) == MULT_EXPR)
7553 tree arg0 = TREE_OPERAND (op1, 0), arg1 = TREE_OPERAND (op1, 1);
7558 if (TREE_CODE (arg0) == INTEGER_CST)
7563 else if (TREE_CODE (arg1) == INTEGER_CST)
7571 else if (TREE_CODE (op1) == INTEGER_CST)
7578 /* Simulate we are delta * 1. */
7580 s = integer_one_node;
7583 for (;; ref = TREE_OPERAND (ref, 0))
7585 if (TREE_CODE (ref) == ARRAY_REF)
7587 /* Remember if this was a multi-dimensional array. */
7588 if (TREE_CODE (TREE_OPERAND (ref, 0)) == ARRAY_REF)
7591 itype = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
7595 step = array_ref_element_size (ref);
7596 if (TREE_CODE (step) != INTEGER_CST)
7601 if (! tree_int_cst_equal (step, s))
7606 /* Try if delta is a multiple of step. */
7607 tree tmp = div_if_zero_remainder (EXACT_DIV_EXPR, op1, step);
7613 /* Only fold here if we can verify we do not overflow one
7614 dimension of a multi-dimensional array. */
7619 if (TREE_CODE (TREE_OPERAND (ref, 1)) != INTEGER_CST
7620 || !INTEGRAL_TYPE_P (itype)
7621 || !TYPE_MAX_VALUE (itype)
7622 || TREE_CODE (TYPE_MAX_VALUE (itype)) != INTEGER_CST)
7625 tmp = fold_binary_loc (loc, PLUS_EXPR, itype,
7626 fold_convert_loc (loc, itype,
7627 TREE_OPERAND (ref, 1)),
7628 fold_convert_loc (loc, itype, delta));
7630 || TREE_CODE (tmp) != INTEGER_CST
7631 || tree_int_cst_lt (TYPE_MAX_VALUE (itype), tmp))
7640 if (!handled_component_p (ref))
7644 /* We found the suitable array reference. So copy everything up to it,
7645 and replace the index. */
7647 pref = TREE_OPERAND (addr, 0);
7648 ret = copy_node (pref);
7649 SET_EXPR_LOCATION (ret, loc);
7654 pref = TREE_OPERAND (pref, 0);
7655 TREE_OPERAND (pos, 0) = copy_node (pref);
7656 pos = TREE_OPERAND (pos, 0);
7659 TREE_OPERAND (pos, 1) = fold_build2_loc (loc, PLUS_EXPR, itype,
7660 fold_convert_loc (loc, itype,
7661 TREE_OPERAND (pos, 1)),
7662 fold_convert_loc (loc, itype, delta));
7664 return fold_build1_loc (loc, ADDR_EXPR, TREE_TYPE (addr), ret);
7668 /* Fold A < X && A + 1 > Y to A < X && A >= Y. Normally A + 1 > Y
7669 means A >= Y && A != MAX, but in this case we know that
7670 A < X <= MAX. INEQ is A + 1 > Y, BOUND is A < X. */
7673 fold_to_nonsharp_ineq_using_bound (location_t loc, tree ineq, tree bound)
7675 tree a, typea, type = TREE_TYPE (ineq), a1, diff, y;
7677 if (TREE_CODE (bound) == LT_EXPR)
7678 a = TREE_OPERAND (bound, 0);
7679 else if (TREE_CODE (bound) == GT_EXPR)
7680 a = TREE_OPERAND (bound, 1);
7684 typea = TREE_TYPE (a);
7685 if (!INTEGRAL_TYPE_P (typea)
7686 && !POINTER_TYPE_P (typea))
7689 if (TREE_CODE (ineq) == LT_EXPR)
7691 a1 = TREE_OPERAND (ineq, 1);
7692 y = TREE_OPERAND (ineq, 0);
7694 else if (TREE_CODE (ineq) == GT_EXPR)
7696 a1 = TREE_OPERAND (ineq, 0);
7697 y = TREE_OPERAND (ineq, 1);
7702 if (TREE_TYPE (a1) != typea)
7705 if (POINTER_TYPE_P (typea))
7707 /* Convert the pointer types into integer before taking the difference. */
7708 tree ta = fold_convert_loc (loc, ssizetype, a);
7709 tree ta1 = fold_convert_loc (loc, ssizetype, a1);
7710 diff = fold_binary_loc (loc, MINUS_EXPR, ssizetype, ta1, ta);
7713 diff = fold_binary_loc (loc, MINUS_EXPR, typea, a1, a);
7715 if (!diff || !integer_onep (diff))
7718 return fold_build2_loc (loc, GE_EXPR, type, a, y);
7721 /* Fold a sum or difference of at least one multiplication.
7722 Returns the folded tree or NULL if no simplification could be made. */
7725 fold_plusminus_mult_expr (location_t loc, enum tree_code code, tree type,
7726 tree arg0, tree arg1)
7728 tree arg00, arg01, arg10, arg11;
7729 tree alt0 = NULL_TREE, alt1 = NULL_TREE, same;
7731 /* (A * C) +- (B * C) -> (A+-B) * C.
7732 (A * C) +- A -> A * (C+-1).
7733 We are most concerned about the case where C is a constant,
7734 but other combinations show up during loop reduction. Since
7735 it is not difficult, try all four possibilities. */
7737 if (TREE_CODE (arg0) == MULT_EXPR)
7739 arg00 = TREE_OPERAND (arg0, 0);
7740 arg01 = TREE_OPERAND (arg0, 1);
7742 else if (TREE_CODE (arg0) == INTEGER_CST)
7744 arg00 = build_one_cst (type);
7749 /* We cannot generate constant 1 for fract. */
7750 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7753 arg01 = build_one_cst (type);
7755 if (TREE_CODE (arg1) == MULT_EXPR)
7757 arg10 = TREE_OPERAND (arg1, 0);
7758 arg11 = TREE_OPERAND (arg1, 1);
7760 else if (TREE_CODE (arg1) == INTEGER_CST)
7762 arg10 = build_one_cst (type);
7763 /* As we canonicalize A - 2 to A + -2 get rid of that sign for
7764 the purpose of this canonicalization. */
7765 if (TREE_INT_CST_HIGH (arg1) == -1
7766 && negate_expr_p (arg1)
7767 && code == PLUS_EXPR)
7769 arg11 = negate_expr (arg1);
7777 /* We cannot generate constant 1 for fract. */
7778 if (ALL_FRACT_MODE_P (TYPE_MODE (type)))
7781 arg11 = build_one_cst (type);
7785 if (operand_equal_p (arg01, arg11, 0))
7786 same = arg01, alt0 = arg00, alt1 = arg10;
7787 else if (operand_equal_p (arg00, arg10, 0))
7788 same = arg00, alt0 = arg01, alt1 = arg11;
7789 else if (operand_equal_p (arg00, arg11, 0))
7790 same = arg00, alt0 = arg01, alt1 = arg10;
7791 else if (operand_equal_p (arg01, arg10, 0))
7792 same = arg01, alt0 = arg00, alt1 = arg11;
7794 /* No identical multiplicands; see if we can find a common
7795 power-of-two factor in non-power-of-two multiplies. This
7796 can help in multi-dimensional array access. */
7797 else if (host_integerp (arg01, 0)
7798 && host_integerp (arg11, 0))
7800 HOST_WIDE_INT int01, int11, tmp;
7803 int01 = TREE_INT_CST_LOW (arg01);
7804 int11 = TREE_INT_CST_LOW (arg11);
7806 /* Move min of absolute values to int11. */
7807 if ((int01 >= 0 ? int01 : -int01)
7808 < (int11 >= 0 ? int11 : -int11))
7810 tmp = int01, int01 = int11, int11 = tmp;
7811 alt0 = arg00, arg00 = arg10, arg10 = alt0;
7818 if (exact_log2 (abs (int11)) > 0 && int01 % int11 == 0
7819 /* The remainder should not be a constant, otherwise we
7820 end up folding i * 4 + 2 to (i * 2 + 1) * 2 which has
7821 increased the number of multiplications necessary. */
7822 && TREE_CODE (arg10) != INTEGER_CST)
7824 alt0 = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (arg00), arg00,
7825 build_int_cst (TREE_TYPE (arg00),
7830 maybe_same = alt0, alt0 = alt1, alt1 = maybe_same;
7835 return fold_build2_loc (loc, MULT_EXPR, type,
7836 fold_build2_loc (loc, code, type,
7837 fold_convert_loc (loc, type, alt0),
7838 fold_convert_loc (loc, type, alt1)),
7839 fold_convert_loc (loc, type, same));
7844 /* Subroutine of native_encode_expr. Encode the INTEGER_CST
7845 specified by EXPR into the buffer PTR of length LEN bytes.
7846 Return the number of bytes placed in the buffer, or zero
7850 native_encode_int (const_tree expr, unsigned char *ptr, int len)
7852 tree type = TREE_TYPE (expr);
7853 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7854 int byte, offset, word, words;
7855 unsigned char value;
7857 if (total_bytes > len)
7859 words = total_bytes / UNITS_PER_WORD;
7861 for (byte = 0; byte < total_bytes; byte++)
7863 int bitpos = byte * BITS_PER_UNIT;
7864 if (bitpos < HOST_BITS_PER_WIDE_INT)
7865 value = (unsigned char) (TREE_INT_CST_LOW (expr) >> bitpos);
7867 value = (unsigned char) (TREE_INT_CST_HIGH (expr)
7868 >> (bitpos - HOST_BITS_PER_WIDE_INT));
7870 if (total_bytes > UNITS_PER_WORD)
7872 word = byte / UNITS_PER_WORD;
7873 if (WORDS_BIG_ENDIAN)
7874 word = (words - 1) - word;
7875 offset = word * UNITS_PER_WORD;
7876 if (BYTES_BIG_ENDIAN)
7877 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7879 offset += byte % UNITS_PER_WORD;
7882 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
7883 ptr[offset] = value;
7889 /* Subroutine of native_encode_expr. Encode the REAL_CST
7890 specified by EXPR into the buffer PTR of length LEN bytes.
7891 Return the number of bytes placed in the buffer, or zero
7895 native_encode_real (const_tree expr, unsigned char *ptr, int len)
7897 tree type = TREE_TYPE (expr);
7898 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
7899 int byte, offset, word, words, bitpos;
7900 unsigned char value;
7902 /* There are always 32 bits in each long, no matter the size of
7903 the hosts long. We handle floating point representations with
7907 if (total_bytes > len)
7909 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
7911 real_to_target (tmp, TREE_REAL_CST_PTR (expr), TYPE_MODE (type));
7913 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
7914 bitpos += BITS_PER_UNIT)
7916 byte = (bitpos / BITS_PER_UNIT) & 3;
7917 value = (unsigned char) (tmp[bitpos / 32] >> (bitpos & 31));
7919 if (UNITS_PER_WORD < 4)
7921 word = byte / UNITS_PER_WORD;
7922 if (WORDS_BIG_ENDIAN)
7923 word = (words - 1) - word;
7924 offset = word * UNITS_PER_WORD;
7925 if (BYTES_BIG_ENDIAN)
7926 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
7928 offset += byte % UNITS_PER_WORD;
7931 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
7932 ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)] = value;
7937 /* Subroutine of native_encode_expr. Encode the COMPLEX_CST
7938 specified by EXPR into the buffer PTR of length LEN bytes.
7939 Return the number of bytes placed in the buffer, or zero
7943 native_encode_complex (const_tree expr, unsigned char *ptr, int len)
7948 part = TREE_REALPART (expr);
7949 rsize = native_encode_expr (part, ptr, len);
7952 part = TREE_IMAGPART (expr);
7953 isize = native_encode_expr (part, ptr+rsize, len-rsize);
7956 return rsize + isize;
7960 /* Subroutine of native_encode_expr. Encode the VECTOR_CST
7961 specified by EXPR into the buffer PTR of length LEN bytes.
7962 Return the number of bytes placed in the buffer, or zero
7966 native_encode_vector (const_tree expr, unsigned char *ptr, int len)
7968 int i, size, offset, count;
7969 tree itype, elem, elements;
7972 elements = TREE_VECTOR_CST_ELTS (expr);
7973 count = TYPE_VECTOR_SUBPARTS (TREE_TYPE (expr));
7974 itype = TREE_TYPE (TREE_TYPE (expr));
7975 size = GET_MODE_SIZE (TYPE_MODE (itype));
7976 for (i = 0; i < count; i++)
7980 elem = TREE_VALUE (elements);
7981 elements = TREE_CHAIN (elements);
7988 if (native_encode_expr (elem, ptr+offset, len-offset) != size)
7993 if (offset + size > len)
7995 memset (ptr+offset, 0, size);
8003 /* Subroutine of native_encode_expr. Encode the STRING_CST
8004 specified by EXPR into the buffer PTR of length LEN bytes.
8005 Return the number of bytes placed in the buffer, or zero
8009 native_encode_string (const_tree expr, unsigned char *ptr, int len)
8011 tree type = TREE_TYPE (expr);
8012 HOST_WIDE_INT total_bytes;
8014 if (TREE_CODE (type) != ARRAY_TYPE
8015 || TREE_CODE (TREE_TYPE (type)) != INTEGER_TYPE
8016 || GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) != BITS_PER_UNIT
8017 || !host_integerp (TYPE_SIZE_UNIT (type), 0))
8019 total_bytes = tree_low_cst (TYPE_SIZE_UNIT (type), 0);
8020 if (total_bytes > len)
8022 if (TREE_STRING_LENGTH (expr) < total_bytes)
8024 memcpy (ptr, TREE_STRING_POINTER (expr), TREE_STRING_LENGTH (expr));
8025 memset (ptr + TREE_STRING_LENGTH (expr), 0,
8026 total_bytes - TREE_STRING_LENGTH (expr));
8029 memcpy (ptr, TREE_STRING_POINTER (expr), total_bytes);
8034 /* Subroutine of fold_view_convert_expr. Encode the INTEGER_CST,
8035 REAL_CST, COMPLEX_CST or VECTOR_CST specified by EXPR into the
8036 buffer PTR of length LEN bytes. Return the number of bytes
8037 placed in the buffer, or zero upon failure. */
8040 native_encode_expr (const_tree expr, unsigned char *ptr, int len)
8042 switch (TREE_CODE (expr))
8045 return native_encode_int (expr, ptr, len);
8048 return native_encode_real (expr, ptr, len);
8051 return native_encode_complex (expr, ptr, len);
8054 return native_encode_vector (expr, ptr, len);
8057 return native_encode_string (expr, ptr, len);
8065 /* Subroutine of native_interpret_expr. Interpret the contents of
8066 the buffer PTR of length LEN as an INTEGER_CST of type TYPE.
8067 If the buffer cannot be interpreted, return NULL_TREE. */
8070 native_interpret_int (tree type, const unsigned char *ptr, int len)
8072 int total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
8073 int byte, offset, word, words;
8074 unsigned char value;
8075 unsigned int HOST_WIDE_INT lo = 0;
8076 HOST_WIDE_INT hi = 0;
8078 if (total_bytes > len)
8080 if (total_bytes * BITS_PER_UNIT > 2 * HOST_BITS_PER_WIDE_INT)
8082 words = total_bytes / UNITS_PER_WORD;
8084 for (byte = 0; byte < total_bytes; byte++)
8086 int bitpos = byte * BITS_PER_UNIT;
8087 if (total_bytes > UNITS_PER_WORD)
8089 word = byte / UNITS_PER_WORD;
8090 if (WORDS_BIG_ENDIAN)
8091 word = (words - 1) - word;
8092 offset = word * UNITS_PER_WORD;
8093 if (BYTES_BIG_ENDIAN)
8094 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
8096 offset += byte % UNITS_PER_WORD;
8099 offset = BYTES_BIG_ENDIAN ? (total_bytes - 1) - byte : byte;
8100 value = ptr[offset];
8102 if (bitpos < HOST_BITS_PER_WIDE_INT)
8103 lo |= (unsigned HOST_WIDE_INT) value << bitpos;
8105 hi |= (unsigned HOST_WIDE_INT) value
8106 << (bitpos - HOST_BITS_PER_WIDE_INT);
8109 return build_int_cst_wide_type (type, lo, hi);
8113 /* Subroutine of native_interpret_expr. Interpret the contents of
8114 the buffer PTR of length LEN as a REAL_CST of type TYPE.
8115 If the buffer cannot be interpreted, return NULL_TREE. */
8118 native_interpret_real (tree type, const unsigned char *ptr, int len)
8120 enum machine_mode mode = TYPE_MODE (type);
8121 int total_bytes = GET_MODE_SIZE (mode);
8122 int byte, offset, word, words, bitpos;
8123 unsigned char value;
8124 /* There are always 32 bits in each long, no matter the size of
8125 the hosts long. We handle floating point representations with
8130 total_bytes = GET_MODE_SIZE (TYPE_MODE (type));
8131 if (total_bytes > len || total_bytes > 24)
8133 words = (32 / BITS_PER_UNIT) / UNITS_PER_WORD;
8135 memset (tmp, 0, sizeof (tmp));
8136 for (bitpos = 0; bitpos < total_bytes * BITS_PER_UNIT;
8137 bitpos += BITS_PER_UNIT)
8139 byte = (bitpos / BITS_PER_UNIT) & 3;
8140 if (UNITS_PER_WORD < 4)
8142 word = byte / UNITS_PER_WORD;
8143 if (WORDS_BIG_ENDIAN)
8144 word = (words - 1) - word;
8145 offset = word * UNITS_PER_WORD;
8146 if (BYTES_BIG_ENDIAN)
8147 offset += (UNITS_PER_WORD - 1) - (byte % UNITS_PER_WORD);
8149 offset += byte % UNITS_PER_WORD;
8152 offset = BYTES_BIG_ENDIAN ? 3 - byte : byte;
8153 value = ptr[offset + ((bitpos / BITS_PER_UNIT) & ~3)];
8155 tmp[bitpos / 32] |= (unsigned long)value << (bitpos & 31);
8158 real_from_target (&r, tmp, mode);
8159 return build_real (type, r);
8163 /* Subroutine of native_interpret_expr. Interpret the contents of
8164 the buffer PTR of length LEN as a COMPLEX_CST of type TYPE.
8165 If the buffer cannot be interpreted, return NULL_TREE. */
8168 native_interpret_complex (tree type, const unsigned char *ptr, int len)
8170 tree etype, rpart, ipart;
8173 etype = TREE_TYPE (type);
8174 size = GET_MODE_SIZE (TYPE_MODE (etype));
8177 rpart = native_interpret_expr (etype, ptr, size);
8180 ipart = native_interpret_expr (etype, ptr+size, size);
8183 return build_complex (type, rpart, ipart);
8187 /* Subroutine of native_interpret_expr. Interpret the contents of
8188 the buffer PTR of length LEN as a VECTOR_CST of type TYPE.
8189 If the buffer cannot be interpreted, return NULL_TREE. */
8192 native_interpret_vector (tree type, const unsigned char *ptr, int len)
8194 tree etype, elem, elements;
8197 etype = TREE_TYPE (type);
8198 size = GET_MODE_SIZE (TYPE_MODE (etype));
8199 count = TYPE_VECTOR_SUBPARTS (type);
8200 if (size * count > len)
8203 elements = NULL_TREE;
8204 for (i = count - 1; i >= 0; i--)
8206 elem = native_interpret_expr (etype, ptr+(i*size), size);
8209 elements = tree_cons (NULL_TREE, elem, elements);
8211 return build_vector (type, elements);
8215 /* Subroutine of fold_view_convert_expr. Interpret the contents of
8216 the buffer PTR of length LEN as a constant of type TYPE. For
8217 INTEGRAL_TYPE_P we return an INTEGER_CST, for SCALAR_FLOAT_TYPE_P
8218 we return a REAL_CST, etc... If the buffer cannot be interpreted,
8219 return NULL_TREE. */
8222 native_interpret_expr (tree type, const unsigned char *ptr, int len)
8224 switch (TREE_CODE (type))
8229 return native_interpret_int (type, ptr, len);
8232 return native_interpret_real (type, ptr, len);
8235 return native_interpret_complex (type, ptr, len);
8238 return native_interpret_vector (type, ptr, len);
8246 /* Fold a VIEW_CONVERT_EXPR of a constant expression EXPR to type
8247 TYPE at compile-time. If we're unable to perform the conversion
8248 return NULL_TREE. */
8251 fold_view_convert_expr (tree type, tree expr)
8253 /* We support up to 512-bit values (for V8DFmode). */
8254 unsigned char buffer[64];
8257 /* Check that the host and target are sane. */
8258 if (CHAR_BIT != 8 || BITS_PER_UNIT != 8)
8261 len = native_encode_expr (expr, buffer, sizeof (buffer));
8265 return native_interpret_expr (type, buffer, len);
8268 /* Build an expression for the address of T. Folds away INDIRECT_REF
8269 to avoid confusing the gimplify process. */
8272 build_fold_addr_expr_with_type_loc (location_t loc, tree t, tree ptrtype)
8274 /* The size of the object is not relevant when talking about its address. */
8275 if (TREE_CODE (t) == WITH_SIZE_EXPR)
8276 t = TREE_OPERAND (t, 0);
8278 /* Note: doesn't apply to ALIGN_INDIRECT_REF */
8279 if (TREE_CODE (t) == INDIRECT_REF
8280 || TREE_CODE (t) == MISALIGNED_INDIRECT_REF)
8282 t = TREE_OPERAND (t, 0);
8284 if (TREE_TYPE (t) != ptrtype)
8286 t = build1 (NOP_EXPR, ptrtype, t);
8287 SET_EXPR_LOCATION (t, loc);
8290 else if (TREE_CODE (t) == VIEW_CONVERT_EXPR)
8292 t = build_fold_addr_expr_loc (loc, TREE_OPERAND (t, 0));
8294 if (TREE_TYPE (t) != ptrtype)
8295 t = fold_convert_loc (loc, ptrtype, t);
8299 t = build1 (ADDR_EXPR, ptrtype, t);
8300 SET_EXPR_LOCATION (t, loc);
8306 /* Build an expression for the address of T. */
8309 build_fold_addr_expr_loc (location_t loc, tree t)
8311 tree ptrtype = build_pointer_type (TREE_TYPE (t));
8313 return build_fold_addr_expr_with_type_loc (loc, t, ptrtype);
8316 /* Fold a unary expression of code CODE and type TYPE with operand
8317 OP0. Return the folded expression if folding is successful.
8318 Otherwise, return NULL_TREE. */
8321 fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
8325 enum tree_code_class kind = TREE_CODE_CLASS (code);
8327 gcc_assert (IS_EXPR_CODE_CLASS (kind)
8328 && TREE_CODE_LENGTH (code) == 1);
8333 if (CONVERT_EXPR_CODE_P (code)
8334 || code == FLOAT_EXPR || code == ABS_EXPR)
8336 /* Don't use STRIP_NOPS, because signedness of argument type
8338 STRIP_SIGN_NOPS (arg0);
8342 /* Strip any conversions that don't change the mode. This
8343 is safe for every expression, except for a comparison
8344 expression because its signedness is derived from its
8347 Note that this is done as an internal manipulation within
8348 the constant folder, in order to find the simplest
8349 representation of the arguments so that their form can be
8350 studied. In any cases, the appropriate type conversions
8351 should be put back in the tree that will get out of the
8357 if (TREE_CODE_CLASS (code) == tcc_unary)
8359 if (TREE_CODE (arg0) == COMPOUND_EXPR)
8360 return build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0),
8361 fold_build1_loc (loc, code, type,
8362 fold_convert_loc (loc, TREE_TYPE (op0),
8363 TREE_OPERAND (arg0, 1))));
8364 else if (TREE_CODE (arg0) == COND_EXPR)
8366 tree arg01 = TREE_OPERAND (arg0, 1);
8367 tree arg02 = TREE_OPERAND (arg0, 2);
8368 if (! VOID_TYPE_P (TREE_TYPE (arg01)))
8369 arg01 = fold_build1_loc (loc, code, type,
8370 fold_convert_loc (loc,
8371 TREE_TYPE (op0), arg01));
8372 if (! VOID_TYPE_P (TREE_TYPE (arg02)))
8373 arg02 = fold_build1_loc (loc, code, type,
8374 fold_convert_loc (loc,
8375 TREE_TYPE (op0), arg02));
8376 tem = fold_build3_loc (loc, COND_EXPR, type, TREE_OPERAND (arg0, 0),
8379 /* If this was a conversion, and all we did was to move into
8380 inside the COND_EXPR, bring it back out. But leave it if
8381 it is a conversion from integer to integer and the
8382 result precision is no wider than a word since such a
8383 conversion is cheap and may be optimized away by combine,
8384 while it couldn't if it were outside the COND_EXPR. Then return
8385 so we don't get into an infinite recursion loop taking the
8386 conversion out and then back in. */
8388 if ((CONVERT_EXPR_CODE_P (code)
8389 || code == NON_LVALUE_EXPR)
8390 && TREE_CODE (tem) == COND_EXPR
8391 && TREE_CODE (TREE_OPERAND (tem, 1)) == code
8392 && TREE_CODE (TREE_OPERAND (tem, 2)) == code
8393 && ! VOID_TYPE_P (TREE_OPERAND (tem, 1))
8394 && ! VOID_TYPE_P (TREE_OPERAND (tem, 2))
8395 && (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))
8396 == TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 2), 0)))
8397 && (! (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8399 (TREE_TYPE (TREE_OPERAND (TREE_OPERAND (tem, 1), 0))))
8400 && TYPE_PRECISION (TREE_TYPE (tem)) <= BITS_PER_WORD)
8401 || flag_syntax_only))
8403 tem = build1 (code, type,
8405 TREE_TYPE (TREE_OPERAND
8406 (TREE_OPERAND (tem, 1), 0)),
8407 TREE_OPERAND (tem, 0),
8408 TREE_OPERAND (TREE_OPERAND (tem, 1), 0),
8409 TREE_OPERAND (TREE_OPERAND (tem, 2), 0)));
8410 SET_EXPR_LOCATION (tem, loc);
8414 else if (COMPARISON_CLASS_P (arg0))
8416 if (TREE_CODE (type) == BOOLEAN_TYPE)
8418 arg0 = copy_node (arg0);
8419 TREE_TYPE (arg0) = type;
8422 else if (TREE_CODE (type) != INTEGER_TYPE)
8423 return fold_build3_loc (loc, COND_EXPR, type, arg0,
8424 fold_build1_loc (loc, code, type,
8426 fold_build1_loc (loc, code, type,
8427 integer_zero_node));
8434 /* Re-association barriers around constants and other re-association
8435 barriers can be removed. */
8436 if (CONSTANT_CLASS_P (op0)
8437 || TREE_CODE (op0) == PAREN_EXPR)
8438 return fold_convert_loc (loc, type, op0);
8443 case FIX_TRUNC_EXPR:
8444 if (TREE_TYPE (op0) == type)
8447 /* If we have (type) (a CMP b) and type is an integral type, return
8448 new expression involving the new type. */
8449 if (COMPARISON_CLASS_P (op0) && INTEGRAL_TYPE_P (type))
8450 return fold_build2_loc (loc, TREE_CODE (op0), type, TREE_OPERAND (op0, 0),
8451 TREE_OPERAND (op0, 1));
8453 /* Handle cases of two conversions in a row. */
8454 if (CONVERT_EXPR_P (op0))
8456 tree inside_type = TREE_TYPE (TREE_OPERAND (op0, 0));
8457 tree inter_type = TREE_TYPE (op0);
8458 int inside_int = INTEGRAL_TYPE_P (inside_type);
8459 int inside_ptr = POINTER_TYPE_P (inside_type);
8460 int inside_float = FLOAT_TYPE_P (inside_type);
8461 int inside_vec = TREE_CODE (inside_type) == VECTOR_TYPE;
8462 unsigned int inside_prec = TYPE_PRECISION (inside_type);
8463 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
8464 int inter_int = INTEGRAL_TYPE_P (inter_type);
8465 int inter_ptr = POINTER_TYPE_P (inter_type);
8466 int inter_float = FLOAT_TYPE_P (inter_type);
8467 int inter_vec = TREE_CODE (inter_type) == VECTOR_TYPE;
8468 unsigned int inter_prec = TYPE_PRECISION (inter_type);
8469 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
8470 int final_int = INTEGRAL_TYPE_P (type);
8471 int final_ptr = POINTER_TYPE_P (type);
8472 int final_float = FLOAT_TYPE_P (type);
8473 int final_vec = TREE_CODE (type) == VECTOR_TYPE;
8474 unsigned int final_prec = TYPE_PRECISION (type);
8475 int final_unsignedp = TYPE_UNSIGNED (type);
8477 /* In addition to the cases of two conversions in a row
8478 handled below, if we are converting something to its own
8479 type via an object of identical or wider precision, neither
8480 conversion is needed. */
8481 if (TYPE_MAIN_VARIANT (inside_type) == TYPE_MAIN_VARIANT (type)
8482 && (((inter_int || inter_ptr) && final_int)
8483 || (inter_float && final_float))
8484 && inter_prec >= final_prec)
8485 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8487 /* Likewise, if the intermediate and initial types are either both
8488 float or both integer, we don't need the middle conversion if the
8489 former is wider than the latter and doesn't change the signedness
8490 (for integers). Avoid this if the final type is a pointer since
8491 then we sometimes need the middle conversion. Likewise if the
8492 final type has a precision not equal to the size of its mode. */
8493 if (((inter_int && inside_int)
8494 || (inter_float && inside_float)
8495 || (inter_vec && inside_vec))
8496 && inter_prec >= inside_prec
8497 && (inter_float || inter_vec
8498 || inter_unsignedp == inside_unsignedp)
8499 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8500 && TYPE_MODE (type) == TYPE_MODE (inter_type))
8502 && (! final_vec || inter_prec == inside_prec))
8503 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8505 /* If we have a sign-extension of a zero-extended value, we can
8506 replace that by a single zero-extension. */
8507 if (inside_int && inter_int && final_int
8508 && inside_prec < inter_prec && inter_prec < final_prec
8509 && inside_unsignedp && !inter_unsignedp)
8510 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8512 /* Two conversions in a row are not needed unless:
8513 - some conversion is floating-point (overstrict for now), or
8514 - some conversion is a vector (overstrict for now), or
8515 - the intermediate type is narrower than both initial and
8517 - the intermediate type and innermost type differ in signedness,
8518 and the outermost type is wider than the intermediate, or
8519 - the initial type is a pointer type and the precisions of the
8520 intermediate and final types differ, or
8521 - the final type is a pointer type and the precisions of the
8522 initial and intermediate types differ. */
8523 if (! inside_float && ! inter_float && ! final_float
8524 && ! inside_vec && ! inter_vec && ! final_vec
8525 && (inter_prec >= inside_prec || inter_prec >= final_prec)
8526 && ! (inside_int && inter_int
8527 && inter_unsignedp != inside_unsignedp
8528 && inter_prec < final_prec)
8529 && ((inter_unsignedp && inter_prec > inside_prec)
8530 == (final_unsignedp && final_prec > inter_prec))
8531 && ! (inside_ptr && inter_prec != final_prec)
8532 && ! (final_ptr && inside_prec != inter_prec)
8533 && ! (final_prec != GET_MODE_BITSIZE (TYPE_MODE (type))
8534 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
8535 return fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 0));
8538 /* Handle (T *)&A.B.C for A being of type T and B and C
8539 living at offset zero. This occurs frequently in
8540 C++ upcasting and then accessing the base. */
8541 if (TREE_CODE (op0) == ADDR_EXPR
8542 && POINTER_TYPE_P (type)
8543 && handled_component_p (TREE_OPERAND (op0, 0)))
8545 HOST_WIDE_INT bitsize, bitpos;
8547 enum machine_mode mode;
8548 int unsignedp, volatilep;
8549 tree base = TREE_OPERAND (op0, 0);
8550 base = get_inner_reference (base, &bitsize, &bitpos, &offset,
8551 &mode, &unsignedp, &volatilep, false);
8552 /* If the reference was to a (constant) zero offset, we can use
8553 the address of the base if it has the same base type
8554 as the result type. */
8555 if (! offset && bitpos == 0
8556 && TYPE_MAIN_VARIANT (TREE_TYPE (type))
8557 == TYPE_MAIN_VARIANT (TREE_TYPE (base)))
8558 return fold_convert_loc (loc, type,
8559 build_fold_addr_expr_loc (loc, base));
8562 if (TREE_CODE (op0) == MODIFY_EXPR
8563 && TREE_CONSTANT (TREE_OPERAND (op0, 1))
8564 /* Detect assigning a bitfield. */
8565 && !(TREE_CODE (TREE_OPERAND (op0, 0)) == COMPONENT_REF
8567 (TREE_OPERAND (TREE_OPERAND (op0, 0), 1))))
8569 /* Don't leave an assignment inside a conversion
8570 unless assigning a bitfield. */
8571 tem = fold_build1_loc (loc, code, type, TREE_OPERAND (op0, 1));
8572 /* First do the assignment, then return converted constant. */
8573 tem = build2 (COMPOUND_EXPR, TREE_TYPE (tem), op0, tem);
8574 TREE_NO_WARNING (tem) = 1;
8575 TREE_USED (tem) = 1;
8576 SET_EXPR_LOCATION (tem, loc);
8580 /* Convert (T)(x & c) into (T)x & (T)c, if c is an integer
8581 constants (if x has signed type, the sign bit cannot be set
8582 in c). This folds extension into the BIT_AND_EXPR.
8583 ??? We don't do it for BOOLEAN_TYPE or ENUMERAL_TYPE because they
8584 very likely don't have maximal range for their precision and this
8585 transformation effectively doesn't preserve non-maximal ranges. */
8586 if (TREE_CODE (type) == INTEGER_TYPE
8587 && TREE_CODE (op0) == BIT_AND_EXPR
8588 && TREE_CODE (TREE_OPERAND (op0, 1)) == INTEGER_CST)
8590 tree and_expr = op0;
8591 tree and0 = TREE_OPERAND (and_expr, 0);
8592 tree and1 = TREE_OPERAND (and_expr, 1);
8595 if (TYPE_UNSIGNED (TREE_TYPE (and_expr))
8596 || (TYPE_PRECISION (type)
8597 <= TYPE_PRECISION (TREE_TYPE (and_expr))))
8599 else if (TYPE_PRECISION (TREE_TYPE (and1))
8600 <= HOST_BITS_PER_WIDE_INT
8601 && host_integerp (and1, 1))
8603 unsigned HOST_WIDE_INT cst;
8605 cst = tree_low_cst (and1, 1);
8606 cst &= (HOST_WIDE_INT) -1
8607 << (TYPE_PRECISION (TREE_TYPE (and1)) - 1);
8608 change = (cst == 0);
8609 #ifdef LOAD_EXTEND_OP
8611 && !flag_syntax_only
8612 && (LOAD_EXTEND_OP (TYPE_MODE (TREE_TYPE (and0)))
8615 tree uns = unsigned_type_for (TREE_TYPE (and0));
8616 and0 = fold_convert_loc (loc, uns, and0);
8617 and1 = fold_convert_loc (loc, uns, and1);
8623 tem = force_fit_type_double (type, TREE_INT_CST_LOW (and1),
8624 TREE_INT_CST_HIGH (and1), 0,
8625 TREE_OVERFLOW (and1));
8626 return fold_build2_loc (loc, BIT_AND_EXPR, type,
8627 fold_convert_loc (loc, type, and0), tem);
8631 /* Convert (T1)(X p+ Y) into ((T1)X p+ Y), for pointer type,
8632 when one of the new casts will fold away. Conservatively we assume
8633 that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
8634 if (POINTER_TYPE_P (type)
8635 && TREE_CODE (arg0) == POINTER_PLUS_EXPR
8636 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
8637 || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
8638 || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
8640 tree arg00 = TREE_OPERAND (arg0, 0);
8641 tree arg01 = TREE_OPERAND (arg0, 1);
8643 return fold_build2_loc (loc,
8644 TREE_CODE (arg0), type,
8645 fold_convert_loc (loc, type, arg00),
8646 fold_convert_loc (loc, sizetype, arg01));
8649 /* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
8650 of the same precision, and X is an integer type not narrower than
8651 types T1 or T2, i.e. the cast (T2)X isn't an extension. */
8652 if (INTEGRAL_TYPE_P (type)
8653 && TREE_CODE (op0) == BIT_NOT_EXPR
8654 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8655 && CONVERT_EXPR_P (TREE_OPERAND (op0, 0))
8656 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8658 tem = TREE_OPERAND (TREE_OPERAND (op0, 0), 0);
8659 if (INTEGRAL_TYPE_P (TREE_TYPE (tem))
8660 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (tem)))
8661 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
8662 fold_convert_loc (loc, type, tem));
8665 /* Convert (T1)(X * Y) into (T1)X * (T1)Y if T1 is narrower than the
8666 type of X and Y (integer types only). */
8667 if (INTEGRAL_TYPE_P (type)
8668 && TREE_CODE (op0) == MULT_EXPR
8669 && INTEGRAL_TYPE_P (TREE_TYPE (op0))
8670 && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (op0)))
8672 /* Be careful not to introduce new overflows. */
8674 if (TYPE_OVERFLOW_WRAPS (type))
8677 mult_type = unsigned_type_for (type);
8679 if (TYPE_PRECISION (mult_type) < TYPE_PRECISION (TREE_TYPE (op0)))
8681 tem = fold_build2_loc (loc, MULT_EXPR, mult_type,
8682 fold_convert_loc (loc, mult_type,
8683 TREE_OPERAND (op0, 0)),
8684 fold_convert_loc (loc, mult_type,
8685 TREE_OPERAND (op0, 1)));
8686 return fold_convert_loc (loc, type, tem);
8690 tem = fold_convert_const (code, type, op0);
8691 return tem ? tem : NULL_TREE;
8693 case ADDR_SPACE_CONVERT_EXPR:
8694 if (integer_zerop (arg0))
8695 return fold_convert_const (code, type, arg0);
8698 case FIXED_CONVERT_EXPR:
8699 tem = fold_convert_const (code, type, arg0);
8700 return tem ? tem : NULL_TREE;
8702 case VIEW_CONVERT_EXPR:
8703 if (TREE_TYPE (op0) == type)
8705 if (TREE_CODE (op0) == VIEW_CONVERT_EXPR)
8706 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8707 type, TREE_OPERAND (op0, 0));
8709 /* For integral conversions with the same precision or pointer
8710 conversions use a NOP_EXPR instead. */
8711 if ((INTEGRAL_TYPE_P (type)
8712 || POINTER_TYPE_P (type))
8713 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8714 || POINTER_TYPE_P (TREE_TYPE (op0)))
8715 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op0)))
8716 return fold_convert_loc (loc, type, op0);
8718 /* Strip inner integral conversions that do not change the precision. */
8719 if (CONVERT_EXPR_P (op0)
8720 && (INTEGRAL_TYPE_P (TREE_TYPE (op0))
8721 || POINTER_TYPE_P (TREE_TYPE (op0)))
8722 && (INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0)))
8723 || POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (op0, 0))))
8724 && (TYPE_PRECISION (TREE_TYPE (op0))
8725 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
8726 return fold_build1_loc (loc, VIEW_CONVERT_EXPR,
8727 type, TREE_OPERAND (op0, 0));
8729 return fold_view_convert_expr (type, op0);
8732 tem = fold_negate_expr (loc, arg0);
8734 return fold_convert_loc (loc, type, tem);
8738 if (TREE_CODE (arg0) == INTEGER_CST || TREE_CODE (arg0) == REAL_CST)
8739 return fold_abs_const (arg0, type);
8740 else if (TREE_CODE (arg0) == NEGATE_EXPR)
8741 return fold_build1_loc (loc, ABS_EXPR, type, TREE_OPERAND (arg0, 0));
8742 /* Convert fabs((double)float) into (double)fabsf(float). */
8743 else if (TREE_CODE (arg0) == NOP_EXPR
8744 && TREE_CODE (type) == REAL_TYPE)
8746 tree targ0 = strip_float_extensions (arg0);
8748 return fold_convert_loc (loc, type,
8749 fold_build1_loc (loc, ABS_EXPR,
8753 /* ABS_EXPR<ABS_EXPR<x>> = ABS_EXPR<x> even if flag_wrapv is on. */
8754 else if (TREE_CODE (arg0) == ABS_EXPR)
8756 else if (tree_expr_nonnegative_p (arg0))
8759 /* Strip sign ops from argument. */
8760 if (TREE_CODE (type) == REAL_TYPE)
8762 tem = fold_strip_sign_ops (arg0);
8764 return fold_build1_loc (loc, ABS_EXPR, type,
8765 fold_convert_loc (loc, type, tem));
8770 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8771 return fold_convert_loc (loc, type, arg0);
8772 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8774 tree itype = TREE_TYPE (type);
8775 tree rpart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 0));
8776 tree ipart = fold_convert_loc (loc, itype, TREE_OPERAND (arg0, 1));
8777 return fold_build2_loc (loc, COMPLEX_EXPR, type, rpart,
8778 negate_expr (ipart));
8780 if (TREE_CODE (arg0) == COMPLEX_CST)
8782 tree itype = TREE_TYPE (type);
8783 tree rpart = fold_convert_loc (loc, itype, TREE_REALPART (arg0));
8784 tree ipart = fold_convert_loc (loc, itype, TREE_IMAGPART (arg0));
8785 return build_complex (type, rpart, negate_expr (ipart));
8787 if (TREE_CODE (arg0) == CONJ_EXPR)
8788 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8792 if (TREE_CODE (arg0) == INTEGER_CST)
8793 return fold_not_const (arg0, type);
8794 else if (TREE_CODE (arg0) == BIT_NOT_EXPR)
8795 return fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
8796 /* Convert ~ (-A) to A - 1. */
8797 else if (INTEGRAL_TYPE_P (type) && TREE_CODE (arg0) == NEGATE_EXPR)
8798 return fold_build2_loc (loc, MINUS_EXPR, type,
8799 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0)),
8800 build_int_cst (type, 1));
8801 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
8802 else if (INTEGRAL_TYPE_P (type)
8803 && ((TREE_CODE (arg0) == MINUS_EXPR
8804 && integer_onep (TREE_OPERAND (arg0, 1)))
8805 || (TREE_CODE (arg0) == PLUS_EXPR
8806 && integer_all_onesp (TREE_OPERAND (arg0, 1)))))
8807 return fold_build1_loc (loc, NEGATE_EXPR, type,
8808 fold_convert_loc (loc, type,
8809 TREE_OPERAND (arg0, 0)));
8810 /* Convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
8811 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8812 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8813 fold_convert_loc (loc, type,
8814 TREE_OPERAND (arg0, 0)))))
8815 return fold_build2_loc (loc, BIT_XOR_EXPR, type, tem,
8816 fold_convert_loc (loc, type,
8817 TREE_OPERAND (arg0, 1)));
8818 else if (TREE_CODE (arg0) == BIT_XOR_EXPR
8819 && (tem = fold_unary_loc (loc, BIT_NOT_EXPR, type,
8820 fold_convert_loc (loc, type,
8821 TREE_OPERAND (arg0, 1)))))
8822 return fold_build2_loc (loc, BIT_XOR_EXPR, type,
8823 fold_convert_loc (loc, type,
8824 TREE_OPERAND (arg0, 0)), tem);
8825 /* Perform BIT_NOT_EXPR on each element individually. */
8826 else if (TREE_CODE (arg0) == VECTOR_CST)
8828 tree elements = TREE_VECTOR_CST_ELTS (arg0), elem, list = NULL_TREE;
8829 int count = TYPE_VECTOR_SUBPARTS (type), i;
8831 for (i = 0; i < count; i++)
8835 elem = TREE_VALUE (elements);
8836 elem = fold_unary_loc (loc, BIT_NOT_EXPR, TREE_TYPE (type), elem);
8837 if (elem == NULL_TREE)
8839 elements = TREE_CHAIN (elements);
8842 elem = build_int_cst (TREE_TYPE (type), -1);
8843 list = tree_cons (NULL_TREE, elem, list);
8846 return build_vector (type, nreverse (list));
8851 case TRUTH_NOT_EXPR:
8852 /* The argument to invert_truthvalue must have Boolean type. */
8853 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
8854 arg0 = fold_convert_loc (loc, boolean_type_node, arg0);
8856 /* Note that the operand of this must be an int
8857 and its values must be 0 or 1.
8858 ("true" is a fixed value perhaps depending on the language,
8859 but we don't handle values other than 1 correctly yet.) */
8860 tem = fold_truth_not_expr (loc, arg0);
8863 return fold_convert_loc (loc, type, tem);
8866 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8867 return fold_convert_loc (loc, type, arg0);
8868 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8869 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 0),
8870 TREE_OPERAND (arg0, 1));
8871 if (TREE_CODE (arg0) == COMPLEX_CST)
8872 return fold_convert_loc (loc, type, TREE_REALPART (arg0));
8873 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8875 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8876 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8877 fold_build1_loc (loc, REALPART_EXPR, itype,
8878 TREE_OPERAND (arg0, 0)),
8879 fold_build1_loc (loc, REALPART_EXPR, itype,
8880 TREE_OPERAND (arg0, 1)));
8881 return fold_convert_loc (loc, type, tem);
8883 if (TREE_CODE (arg0) == CONJ_EXPR)
8885 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8886 tem = fold_build1_loc (loc, REALPART_EXPR, itype,
8887 TREE_OPERAND (arg0, 0));
8888 return fold_convert_loc (loc, type, tem);
8890 if (TREE_CODE (arg0) == CALL_EXPR)
8892 tree fn = get_callee_fndecl (arg0);
8893 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8894 switch (DECL_FUNCTION_CODE (fn))
8896 CASE_FLT_FN (BUILT_IN_CEXPI):
8897 fn = mathfn_built_in (type, BUILT_IN_COS);
8899 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8909 if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
8910 return fold_convert_loc (loc, type, integer_zero_node);
8911 if (TREE_CODE (arg0) == COMPLEX_EXPR)
8912 return omit_one_operand_loc (loc, type, TREE_OPERAND (arg0, 1),
8913 TREE_OPERAND (arg0, 0));
8914 if (TREE_CODE (arg0) == COMPLEX_CST)
8915 return fold_convert_loc (loc, type, TREE_IMAGPART (arg0));
8916 if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
8918 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8919 tem = fold_build2_loc (loc, TREE_CODE (arg0), itype,
8920 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8921 TREE_OPERAND (arg0, 0)),
8922 fold_build1_loc (loc, IMAGPART_EXPR, itype,
8923 TREE_OPERAND (arg0, 1)));
8924 return fold_convert_loc (loc, type, tem);
8926 if (TREE_CODE (arg0) == CONJ_EXPR)
8928 tree itype = TREE_TYPE (TREE_TYPE (arg0));
8929 tem = fold_build1_loc (loc, IMAGPART_EXPR, itype, TREE_OPERAND (arg0, 0));
8930 return fold_convert_loc (loc, type, negate_expr (tem));
8932 if (TREE_CODE (arg0) == CALL_EXPR)
8934 tree fn = get_callee_fndecl (arg0);
8935 if (fn && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
8936 switch (DECL_FUNCTION_CODE (fn))
8938 CASE_FLT_FN (BUILT_IN_CEXPI):
8939 fn = mathfn_built_in (type, BUILT_IN_SIN);
8941 return build_call_expr_loc (loc, fn, 1, CALL_EXPR_ARG (arg0, 0));
8952 } /* switch (code) */
8956 /* If the operation was a conversion do _not_ mark a resulting constant
8957 with TREE_OVERFLOW if the original constant was not. These conversions
8958 have implementation defined behavior and retaining the TREE_OVERFLOW
8959 flag here would confuse later passes such as VRP. */
8961 fold_unary_ignore_overflow_loc (location_t loc, enum tree_code code,
8962 tree type, tree op0)
8964 tree res = fold_unary_loc (loc, code, type, op0);
8966 && TREE_CODE (res) == INTEGER_CST
8967 && TREE_CODE (op0) == INTEGER_CST
8968 && CONVERT_EXPR_CODE_P (code))
8969 TREE_OVERFLOW (res) = TREE_OVERFLOW (op0);
8974 /* Fold a binary expression of code CODE and type TYPE with operands
8975 OP0 and OP1, containing either a MIN-MAX or a MAX-MIN combination.
8976 Return the folded expression if folding is successful. Otherwise,
8977 return NULL_TREE. */
8980 fold_minmax (location_t loc, enum tree_code code, tree type, tree op0, tree op1)
8982 enum tree_code compl_code;
8984 if (code == MIN_EXPR)
8985 compl_code = MAX_EXPR;
8986 else if (code == MAX_EXPR)
8987 compl_code = MIN_EXPR;
8991 /* MIN (MAX (a, b), b) == b. */
8992 if (TREE_CODE (op0) == compl_code
8993 && operand_equal_p (TREE_OPERAND (op0, 1), op1, 0))
8994 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 0));
8996 /* MIN (MAX (b, a), b) == b. */
8997 if (TREE_CODE (op0) == compl_code
8998 && operand_equal_p (TREE_OPERAND (op0, 0), op1, 0)
8999 && reorder_operands_p (TREE_OPERAND (op0, 1), op1))
9000 return omit_one_operand_loc (loc, type, op1, TREE_OPERAND (op0, 1));
9002 /* MIN (a, MAX (a, b)) == a. */
9003 if (TREE_CODE (op1) == compl_code
9004 && operand_equal_p (op0, TREE_OPERAND (op1, 0), 0)
9005 && reorder_operands_p (op0, TREE_OPERAND (op1, 1)))
9006 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 1));
9008 /* MIN (a, MAX (b, a)) == a. */
9009 if (TREE_CODE (op1) == compl_code
9010 && operand_equal_p (op0, TREE_OPERAND (op1, 1), 0)
9011 && reorder_operands_p (op0, TREE_OPERAND (op1, 0)))
9012 return omit_one_operand_loc (loc, type, op0, TREE_OPERAND (op1, 0));
9017 /* Helper that tries to canonicalize the comparison ARG0 CODE ARG1
9018 by changing CODE to reduce the magnitude of constants involved in
9019 ARG0 of the comparison.
9020 Returns a canonicalized comparison tree if a simplification was
9021 possible, otherwise returns NULL_TREE.
9022 Set *STRICT_OVERFLOW_P to true if the canonicalization is only
9023 valid if signed overflow is undefined. */
9026 maybe_canonicalize_comparison_1 (location_t loc, enum tree_code code, tree type,
9027 tree arg0, tree arg1,
9028 bool *strict_overflow_p)
9030 enum tree_code code0 = TREE_CODE (arg0);
9031 tree t, cst0 = NULL_TREE;
9035 /* Match A +- CST code arg1 and CST code arg1. We can change the
9036 first form only if overflow is undefined. */
9037 if (!((TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9038 /* In principle pointers also have undefined overflow behavior,
9039 but that causes problems elsewhere. */
9040 && !POINTER_TYPE_P (TREE_TYPE (arg0))
9041 && (code0 == MINUS_EXPR
9042 || code0 == PLUS_EXPR)
9043 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9044 || code0 == INTEGER_CST))
9047 /* Identify the constant in arg0 and its sign. */
9048 if (code0 == INTEGER_CST)
9051 cst0 = TREE_OPERAND (arg0, 1);
9052 sgn0 = tree_int_cst_sgn (cst0);
9054 /* Overflowed constants and zero will cause problems. */
9055 if (integer_zerop (cst0)
9056 || TREE_OVERFLOW (cst0))
9059 /* See if we can reduce the magnitude of the constant in
9060 arg0 by changing the comparison code. */
9061 if (code0 == INTEGER_CST)
9063 /* CST <= arg1 -> CST-1 < arg1. */
9064 if (code == LE_EXPR && sgn0 == 1)
9066 /* -CST < arg1 -> -CST-1 <= arg1. */
9067 else if (code == LT_EXPR && sgn0 == -1)
9069 /* CST > arg1 -> CST-1 >= arg1. */
9070 else if (code == GT_EXPR && sgn0 == 1)
9072 /* -CST >= arg1 -> -CST-1 > arg1. */
9073 else if (code == GE_EXPR && sgn0 == -1)
9077 /* arg1 code' CST' might be more canonical. */
9082 /* A - CST < arg1 -> A - CST-1 <= arg1. */
9084 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
9086 /* A + CST > arg1 -> A + CST-1 >= arg1. */
9087 else if (code == GT_EXPR
9088 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
9090 /* A + CST <= arg1 -> A + CST-1 < arg1. */
9091 else if (code == LE_EXPR
9092 && code0 == ((sgn0 == -1) ? MINUS_EXPR : PLUS_EXPR))
9094 /* A - CST >= arg1 -> A - CST-1 > arg1. */
9095 else if (code == GE_EXPR
9096 && code0 == ((sgn0 == -1) ? PLUS_EXPR : MINUS_EXPR))
9100 *strict_overflow_p = true;
9103 /* Now build the constant reduced in magnitude. But not if that
9104 would produce one outside of its types range. */
9105 if (INTEGRAL_TYPE_P (TREE_TYPE (cst0))
9107 && TYPE_MIN_VALUE (TREE_TYPE (cst0))
9108 && tree_int_cst_equal (cst0, TYPE_MIN_VALUE (TREE_TYPE (cst0))))
9110 && TYPE_MAX_VALUE (TREE_TYPE (cst0))
9111 && tree_int_cst_equal (cst0, TYPE_MAX_VALUE (TREE_TYPE (cst0))))))
9112 /* We cannot swap the comparison here as that would cause us to
9113 endlessly recurse. */
9116 t = int_const_binop (sgn0 == -1 ? PLUS_EXPR : MINUS_EXPR,
9117 cst0, build_int_cst (TREE_TYPE (cst0), 1), 0);
9118 if (code0 != INTEGER_CST)
9119 t = fold_build2_loc (loc, code0, TREE_TYPE (arg0), TREE_OPERAND (arg0, 0), t);
9121 /* If swapping might yield to a more canonical form, do so. */
9123 return fold_build2_loc (loc, swap_tree_comparison (code), type, arg1, t);
9125 return fold_build2_loc (loc, code, type, t, arg1);
9128 /* Canonicalize the comparison ARG0 CODE ARG1 with type TYPE with undefined
9129 overflow further. Try to decrease the magnitude of constants involved
9130 by changing LE_EXPR and GE_EXPR to LT_EXPR and GT_EXPR or vice versa
9131 and put sole constants at the second argument position.
9132 Returns the canonicalized tree if changed, otherwise NULL_TREE. */
9135 maybe_canonicalize_comparison (location_t loc, enum tree_code code, tree type,
9136 tree arg0, tree arg1)
9139 bool strict_overflow_p;
9140 const char * const warnmsg = G_("assuming signed overflow does not occur "
9141 "when reducing constant in comparison");
9143 /* Try canonicalization by simplifying arg0. */
9144 strict_overflow_p = false;
9145 t = maybe_canonicalize_comparison_1 (loc, code, type, arg0, arg1,
9146 &strict_overflow_p);
9149 if (strict_overflow_p)
9150 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
9154 /* Try canonicalization by simplifying arg1 using the swapped
9156 code = swap_tree_comparison (code);
9157 strict_overflow_p = false;
9158 t = maybe_canonicalize_comparison_1 (loc, code, type, arg1, arg0,
9159 &strict_overflow_p);
9160 if (t && strict_overflow_p)
9161 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_MAGNITUDE);
9165 /* Return whether BASE + OFFSET + BITPOS may wrap around the address
9166 space. This is used to avoid issuing overflow warnings for
9167 expressions like &p->x which can not wrap. */
9170 pointer_may_wrap_p (tree base, tree offset, HOST_WIDE_INT bitpos)
9172 unsigned HOST_WIDE_INT offset_low, total_low;
9173 HOST_WIDE_INT size, offset_high, total_high;
9175 if (!POINTER_TYPE_P (TREE_TYPE (base)))
9181 if (offset == NULL_TREE)
9186 else if (TREE_CODE (offset) != INTEGER_CST || TREE_OVERFLOW (offset))
9190 offset_low = TREE_INT_CST_LOW (offset);
9191 offset_high = TREE_INT_CST_HIGH (offset);
9194 if (add_double_with_sign (offset_low, offset_high,
9195 bitpos / BITS_PER_UNIT, 0,
9196 &total_low, &total_high,
9200 if (total_high != 0)
9203 size = int_size_in_bytes (TREE_TYPE (TREE_TYPE (base)));
9207 /* We can do slightly better for SIZE if we have an ADDR_EXPR of an
9209 if (TREE_CODE (base) == ADDR_EXPR)
9211 HOST_WIDE_INT base_size;
9213 base_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (base, 0)));
9214 if (base_size > 0 && size < base_size)
9218 return total_low > (unsigned HOST_WIDE_INT) size;
9221 /* Subroutine of fold_binary. This routine performs all of the
9222 transformations that are common to the equality/inequality
9223 operators (EQ_EXPR and NE_EXPR) and the ordering operators
9224 (LT_EXPR, LE_EXPR, GE_EXPR and GT_EXPR). Callers other than
9225 fold_binary should call fold_binary. Fold a comparison with
9226 tree code CODE and type TYPE with operands OP0 and OP1. Return
9227 the folded comparison or NULL_TREE. */
9230 fold_comparison (location_t loc, enum tree_code code, tree type,
9233 tree arg0, arg1, tem;
9238 STRIP_SIGN_NOPS (arg0);
9239 STRIP_SIGN_NOPS (arg1);
9241 tem = fold_relational_const (code, type, arg0, arg1);
9242 if (tem != NULL_TREE)
9245 /* If one arg is a real or integer constant, put it last. */
9246 if (tree_swap_operands_p (arg0, arg1, true))
9247 return fold_build2_loc (loc, swap_tree_comparison (code), type, op1, op0);
9249 /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */
9250 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9251 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9252 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9253 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
9254 && (TREE_CODE (arg1) == INTEGER_CST
9255 && !TREE_OVERFLOW (arg1)))
9257 tree const1 = TREE_OPERAND (arg0, 1);
9259 tree variable = TREE_OPERAND (arg0, 0);
9262 lhs_add = TREE_CODE (arg0) != PLUS_EXPR;
9264 lhs = fold_build2_loc (loc, lhs_add ? PLUS_EXPR : MINUS_EXPR,
9265 TREE_TYPE (arg1), const2, const1);
9267 /* If the constant operation overflowed this can be
9268 simplified as a comparison against INT_MAX/INT_MIN. */
9269 if (TREE_CODE (lhs) == INTEGER_CST
9270 && TREE_OVERFLOW (lhs))
9272 int const1_sgn = tree_int_cst_sgn (const1);
9273 enum tree_code code2 = code;
9275 /* Get the sign of the constant on the lhs if the
9276 operation were VARIABLE + CONST1. */
9277 if (TREE_CODE (arg0) == MINUS_EXPR)
9278 const1_sgn = -const1_sgn;
9280 /* The sign of the constant determines if we overflowed
9281 INT_MAX (const1_sgn == -1) or INT_MIN (const1_sgn == 1).
9282 Canonicalize to the INT_MIN overflow by swapping the comparison
9284 if (const1_sgn == -1)
9285 code2 = swap_tree_comparison (code);
9287 /* We now can look at the canonicalized case
9288 VARIABLE + 1 CODE2 INT_MIN
9289 and decide on the result. */
9290 if (code2 == LT_EXPR
9292 || code2 == EQ_EXPR)
9293 return omit_one_operand_loc (loc, type, boolean_false_node, variable);
9294 else if (code2 == NE_EXPR
9296 || code2 == GT_EXPR)
9297 return omit_one_operand_loc (loc, type, boolean_true_node, variable);
9300 if (TREE_CODE (lhs) == TREE_CODE (arg1)
9301 && (TREE_CODE (lhs) != INTEGER_CST
9302 || !TREE_OVERFLOW (lhs)))
9304 fold_overflow_warning (("assuming signed overflow does not occur "
9305 "when changing X +- C1 cmp C2 to "
9307 WARN_STRICT_OVERFLOW_COMPARISON);
9308 return fold_build2_loc (loc, code, type, variable, lhs);
9312 /* For comparisons of pointers we can decompose it to a compile time
9313 comparison of the base objects and the offsets into the object.
9314 This requires at least one operand being an ADDR_EXPR or a
9315 POINTER_PLUS_EXPR to do more than the operand_equal_p test below. */
9316 if (POINTER_TYPE_P (TREE_TYPE (arg0))
9317 && (TREE_CODE (arg0) == ADDR_EXPR
9318 || TREE_CODE (arg1) == ADDR_EXPR
9319 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
9320 || TREE_CODE (arg1) == POINTER_PLUS_EXPR))
9322 tree base0, base1, offset0 = NULL_TREE, offset1 = NULL_TREE;
9323 HOST_WIDE_INT bitsize, bitpos0 = 0, bitpos1 = 0;
9324 enum machine_mode mode;
9325 int volatilep, unsignedp;
9326 bool indirect_base0 = false, indirect_base1 = false;
9328 /* Get base and offset for the access. Strip ADDR_EXPR for
9329 get_inner_reference, but put it back by stripping INDIRECT_REF
9330 off the base object if possible. indirect_baseN will be true
9331 if baseN is not an address but refers to the object itself. */
9333 if (TREE_CODE (arg0) == ADDR_EXPR)
9335 base0 = get_inner_reference (TREE_OPERAND (arg0, 0),
9336 &bitsize, &bitpos0, &offset0, &mode,
9337 &unsignedp, &volatilep, false);
9338 if (TREE_CODE (base0) == INDIRECT_REF)
9339 base0 = TREE_OPERAND (base0, 0);
9341 indirect_base0 = true;
9343 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
9345 base0 = TREE_OPERAND (arg0, 0);
9346 offset0 = TREE_OPERAND (arg0, 1);
9350 if (TREE_CODE (arg1) == ADDR_EXPR)
9352 base1 = get_inner_reference (TREE_OPERAND (arg1, 0),
9353 &bitsize, &bitpos1, &offset1, &mode,
9354 &unsignedp, &volatilep, false);
9355 if (TREE_CODE (base1) == INDIRECT_REF)
9356 base1 = TREE_OPERAND (base1, 0);
9358 indirect_base1 = true;
9360 else if (TREE_CODE (arg1) == POINTER_PLUS_EXPR)
9362 base1 = TREE_OPERAND (arg1, 0);
9363 offset1 = TREE_OPERAND (arg1, 1);
9366 /* If we have equivalent bases we might be able to simplify. */
9367 if (indirect_base0 == indirect_base1
9368 && operand_equal_p (base0, base1, 0))
9370 /* We can fold this expression to a constant if the non-constant
9371 offset parts are equal. */
9372 if ((offset0 == offset1
9373 || (offset0 && offset1
9374 && operand_equal_p (offset0, offset1, 0)))
9377 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9382 && bitpos0 != bitpos1
9383 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9384 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9385 fold_overflow_warning (("assuming pointer wraparound does not "
9386 "occur when comparing P +- C1 with "
9388 WARN_STRICT_OVERFLOW_CONDITIONAL);
9393 return constant_boolean_node (bitpos0 == bitpos1, type);
9395 return constant_boolean_node (bitpos0 != bitpos1, type);
9397 return constant_boolean_node (bitpos0 < bitpos1, type);
9399 return constant_boolean_node (bitpos0 <= bitpos1, type);
9401 return constant_boolean_node (bitpos0 >= bitpos1, type);
9403 return constant_boolean_node (bitpos0 > bitpos1, type);
9407 /* We can simplify the comparison to a comparison of the variable
9408 offset parts if the constant offset parts are equal.
9409 Be careful to use signed size type here because otherwise we
9410 mess with array offsets in the wrong way. This is possible
9411 because pointer arithmetic is restricted to retain within an
9412 object and overflow on pointer differences is undefined as of
9413 6.5.6/8 and /9 with respect to the signed ptrdiff_t. */
9414 else if (bitpos0 == bitpos1
9415 && ((code == EQ_EXPR || code == NE_EXPR)
9416 || POINTER_TYPE_OVERFLOW_UNDEFINED))
9418 tree signed_size_type_node;
9419 signed_size_type_node = signed_type_for (size_type_node);
9421 /* By converting to signed size type we cover middle-end pointer
9422 arithmetic which operates on unsigned pointer types of size
9423 type size and ARRAY_REF offsets which are properly sign or
9424 zero extended from their type in case it is narrower than
9426 if (offset0 == NULL_TREE)
9427 offset0 = build_int_cst (signed_size_type_node, 0);
9429 offset0 = fold_convert_loc (loc, signed_size_type_node,
9431 if (offset1 == NULL_TREE)
9432 offset1 = build_int_cst (signed_size_type_node, 0);
9434 offset1 = fold_convert_loc (loc, signed_size_type_node,
9439 && (pointer_may_wrap_p (base0, offset0, bitpos0)
9440 || pointer_may_wrap_p (base1, offset1, bitpos1)))
9441 fold_overflow_warning (("assuming pointer wraparound does not "
9442 "occur when comparing P +- C1 with "
9444 WARN_STRICT_OVERFLOW_COMPARISON);
9446 return fold_build2_loc (loc, code, type, offset0, offset1);
9449 /* For non-equal bases we can simplify if they are addresses
9450 of local binding decls or constants. */
9451 else if (indirect_base0 && indirect_base1
9452 /* We know that !operand_equal_p (base0, base1, 0)
9453 because the if condition was false. But make
9454 sure two decls are not the same. */
9456 && TREE_CODE (arg0) == ADDR_EXPR
9457 && TREE_CODE (arg1) == ADDR_EXPR
9458 && (((TREE_CODE (base0) == VAR_DECL
9459 || TREE_CODE (base0) == PARM_DECL)
9460 && (targetm.binds_local_p (base0)
9461 || CONSTANT_CLASS_P (base1)))
9462 || CONSTANT_CLASS_P (base0))
9463 && (((TREE_CODE (base1) == VAR_DECL
9464 || TREE_CODE (base1) == PARM_DECL)
9465 && (targetm.binds_local_p (base1)
9466 || CONSTANT_CLASS_P (base0)))
9467 || CONSTANT_CLASS_P (base1)))
9469 if (code == EQ_EXPR)
9470 return omit_two_operands_loc (loc, type, boolean_false_node,
9472 else if (code == NE_EXPR)
9473 return omit_two_operands_loc (loc, type, boolean_true_node,
9476 /* For equal offsets we can simplify to a comparison of the
9478 else if (bitpos0 == bitpos1
9480 ? base0 != TREE_OPERAND (arg0, 0) : base0 != arg0)
9482 ? base1 != TREE_OPERAND (arg1, 0) : base1 != arg1)
9483 && ((offset0 == offset1)
9484 || (offset0 && offset1
9485 && operand_equal_p (offset0, offset1, 0))))
9488 base0 = build_fold_addr_expr_loc (loc, base0);
9490 base1 = build_fold_addr_expr_loc (loc, base1);
9491 return fold_build2_loc (loc, code, type, base0, base1);
9495 /* Transform comparisons of the form X +- C1 CMP Y +- C2 to
9496 X CMP Y +- C2 +- C1 for signed X, Y. This is valid if
9497 the resulting offset is smaller in absolute value than the
9499 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9500 && (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
9501 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9502 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9503 && (TREE_CODE (arg1) == PLUS_EXPR || TREE_CODE (arg1) == MINUS_EXPR)
9504 && (TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
9505 && !TREE_OVERFLOW (TREE_OPERAND (arg1, 1))))
9507 tree const1 = TREE_OPERAND (arg0, 1);
9508 tree const2 = TREE_OPERAND (arg1, 1);
9509 tree variable1 = TREE_OPERAND (arg0, 0);
9510 tree variable2 = TREE_OPERAND (arg1, 0);
9512 const char * const warnmsg = G_("assuming signed overflow does not "
9513 "occur when combining constants around "
9516 /* Put the constant on the side where it doesn't overflow and is
9517 of lower absolute value than before. */
9518 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9519 ? MINUS_EXPR : PLUS_EXPR,
9521 if (!TREE_OVERFLOW (cst)
9522 && tree_int_cst_compare (const2, cst) == tree_int_cst_sgn (const2))
9524 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9525 return fold_build2_loc (loc, code, type,
9527 fold_build2_loc (loc,
9528 TREE_CODE (arg1), TREE_TYPE (arg1),
9532 cst = int_const_binop (TREE_CODE (arg0) == TREE_CODE (arg1)
9533 ? MINUS_EXPR : PLUS_EXPR,
9535 if (!TREE_OVERFLOW (cst)
9536 && tree_int_cst_compare (const1, cst) == tree_int_cst_sgn (const1))
9538 fold_overflow_warning (warnmsg, WARN_STRICT_OVERFLOW_COMPARISON);
9539 return fold_build2_loc (loc, code, type,
9540 fold_build2_loc (loc, TREE_CODE (arg0), TREE_TYPE (arg0),
9546 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
9547 signed arithmetic case. That form is created by the compiler
9548 often enough for folding it to be of value. One example is in
9549 computing loop trip counts after Operator Strength Reduction. */
9550 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg0))
9551 && TREE_CODE (arg0) == MULT_EXPR
9552 && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9553 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)))
9554 && integer_zerop (arg1))
9556 tree const1 = TREE_OPERAND (arg0, 1);
9557 tree const2 = arg1; /* zero */
9558 tree variable1 = TREE_OPERAND (arg0, 0);
9559 enum tree_code cmp_code = code;
9561 gcc_assert (!integer_zerop (const1));
9563 fold_overflow_warning (("assuming signed overflow does not occur when "
9564 "eliminating multiplication in comparison "
9566 WARN_STRICT_OVERFLOW_COMPARISON);
9568 /* If const1 is negative we swap the sense of the comparison. */
9569 if (tree_int_cst_sgn (const1) < 0)
9570 cmp_code = swap_tree_comparison (cmp_code);
9572 return fold_build2_loc (loc, cmp_code, type, variable1, const2);
9575 tem = maybe_canonicalize_comparison (loc, code, type, op0, op1);
9579 if (FLOAT_TYPE_P (TREE_TYPE (arg0)))
9581 tree targ0 = strip_float_extensions (arg0);
9582 tree targ1 = strip_float_extensions (arg1);
9583 tree newtype = TREE_TYPE (targ0);
9585 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
9586 newtype = TREE_TYPE (targ1);
9588 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
9589 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
9590 return fold_build2_loc (loc, code, type,
9591 fold_convert_loc (loc, newtype, targ0),
9592 fold_convert_loc (loc, newtype, targ1));
9594 /* (-a) CMP (-b) -> b CMP a */
9595 if (TREE_CODE (arg0) == NEGATE_EXPR
9596 && TREE_CODE (arg1) == NEGATE_EXPR)
9597 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg1, 0),
9598 TREE_OPERAND (arg0, 0));
9600 if (TREE_CODE (arg1) == REAL_CST)
9602 REAL_VALUE_TYPE cst;
9603 cst = TREE_REAL_CST (arg1);
9605 /* (-a) CMP CST -> a swap(CMP) (-CST) */
9606 if (TREE_CODE (arg0) == NEGATE_EXPR)
9607 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9608 TREE_OPERAND (arg0, 0),
9609 build_real (TREE_TYPE (arg1),
9610 REAL_VALUE_NEGATE (cst)));
9612 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
9613 /* a CMP (-0) -> a CMP 0 */
9614 if (REAL_VALUE_MINUS_ZERO (cst))
9615 return fold_build2_loc (loc, code, type, arg0,
9616 build_real (TREE_TYPE (arg1), dconst0));
9618 /* x != NaN is always true, other ops are always false. */
9619 if (REAL_VALUE_ISNAN (cst)
9620 && ! HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg1))))
9622 tem = (code == NE_EXPR) ? integer_one_node : integer_zero_node;
9623 return omit_one_operand_loc (loc, type, tem, arg0);
9626 /* Fold comparisons against infinity. */
9627 if (REAL_VALUE_ISINF (cst)
9628 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1))))
9630 tem = fold_inf_compare (loc, code, type, arg0, arg1);
9631 if (tem != NULL_TREE)
9636 /* If this is a comparison of a real constant with a PLUS_EXPR
9637 or a MINUS_EXPR of a real constant, we can convert it into a
9638 comparison with a revised real constant as long as no overflow
9639 occurs when unsafe_math_optimizations are enabled. */
9640 if (flag_unsafe_math_optimizations
9641 && TREE_CODE (arg1) == REAL_CST
9642 && (TREE_CODE (arg0) == PLUS_EXPR
9643 || TREE_CODE (arg0) == MINUS_EXPR)
9644 && TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
9645 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
9646 ? MINUS_EXPR : PLUS_EXPR,
9647 arg1, TREE_OPERAND (arg0, 1), 0))
9648 && !TREE_OVERFLOW (tem))
9649 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
9651 /* Likewise, we can simplify a comparison of a real constant with
9652 a MINUS_EXPR whose first operand is also a real constant, i.e.
9653 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
9654 floating-point types only if -fassociative-math is set. */
9655 if (flag_associative_math
9656 && TREE_CODE (arg1) == REAL_CST
9657 && TREE_CODE (arg0) == MINUS_EXPR
9658 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST
9659 && 0 != (tem = const_binop (MINUS_EXPR, TREE_OPERAND (arg0, 0),
9661 && !TREE_OVERFLOW (tem))
9662 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9663 TREE_OPERAND (arg0, 1), tem);
9665 /* Fold comparisons against built-in math functions. */
9666 if (TREE_CODE (arg1) == REAL_CST
9667 && flag_unsafe_math_optimizations
9668 && ! flag_errno_math)
9670 enum built_in_function fcode = builtin_mathfn_code (arg0);
9672 if (fcode != END_BUILTINS)
9674 tem = fold_mathfn_compare (loc, fcode, code, type, arg0, arg1);
9675 if (tem != NULL_TREE)
9681 if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
9682 && CONVERT_EXPR_P (arg0))
9684 /* If we are widening one operand of an integer comparison,
9685 see if the other operand is similarly being widened. Perhaps we
9686 can do the comparison in the narrower type. */
9687 tem = fold_widened_comparison (loc, code, type, arg0, arg1);
9691 /* Or if we are changing signedness. */
9692 tem = fold_sign_changed_comparison (loc, code, type, arg0, arg1);
9697 /* If this is comparing a constant with a MIN_EXPR or a MAX_EXPR of a
9698 constant, we can simplify it. */
9699 if (TREE_CODE (arg1) == INTEGER_CST
9700 && (TREE_CODE (arg0) == MIN_EXPR
9701 || TREE_CODE (arg0) == MAX_EXPR)
9702 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
9704 tem = optimize_minmax_comparison (loc, code, type, op0, op1);
9709 /* Simplify comparison of something with itself. (For IEEE
9710 floating-point, we can only do some of these simplifications.) */
9711 if (operand_equal_p (arg0, arg1, 0))
9716 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9717 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9718 return constant_boolean_node (1, type);
9723 if (! FLOAT_TYPE_P (TREE_TYPE (arg0))
9724 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9725 return constant_boolean_node (1, type);
9726 return fold_build2_loc (loc, EQ_EXPR, type, arg0, arg1);
9729 /* For NE, we can only do this simplification if integer
9730 or we don't honor IEEE floating point NaNs. */
9731 if (FLOAT_TYPE_P (TREE_TYPE (arg0))
9732 && HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0))))
9734 /* ... fall through ... */
9737 return constant_boolean_node (0, type);
9743 /* If we are comparing an expression that just has comparisons
9744 of two integer values, arithmetic expressions of those comparisons,
9745 and constants, we can simplify it. There are only three cases
9746 to check: the two values can either be equal, the first can be
9747 greater, or the second can be greater. Fold the expression for
9748 those three values. Since each value must be 0 or 1, we have
9749 eight possibilities, each of which corresponds to the constant 0
9750 or 1 or one of the six possible comparisons.
9752 This handles common cases like (a > b) == 0 but also handles
9753 expressions like ((x > y) - (y > x)) > 0, which supposedly
9754 occur in macroized code. */
9756 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) != INTEGER_CST)
9758 tree cval1 = 0, cval2 = 0;
9761 if (twoval_comparison_p (arg0, &cval1, &cval2, &save_p)
9762 /* Don't handle degenerate cases here; they should already
9763 have been handled anyway. */
9764 && cval1 != 0 && cval2 != 0
9765 && ! (TREE_CONSTANT (cval1) && TREE_CONSTANT (cval2))
9766 && TREE_TYPE (cval1) == TREE_TYPE (cval2)
9767 && INTEGRAL_TYPE_P (TREE_TYPE (cval1))
9768 && TYPE_MAX_VALUE (TREE_TYPE (cval1))
9769 && TYPE_MAX_VALUE (TREE_TYPE (cval2))
9770 && ! operand_equal_p (TYPE_MIN_VALUE (TREE_TYPE (cval1)),
9771 TYPE_MAX_VALUE (TREE_TYPE (cval2)), 0))
9773 tree maxval = TYPE_MAX_VALUE (TREE_TYPE (cval1));
9774 tree minval = TYPE_MIN_VALUE (TREE_TYPE (cval1));
9776 /* We can't just pass T to eval_subst in case cval1 or cval2
9777 was the same as ARG1. */
9780 = fold_build2_loc (loc, code, type,
9781 eval_subst (loc, arg0, cval1, maxval,
9785 = fold_build2_loc (loc, code, type,
9786 eval_subst (loc, arg0, cval1, maxval,
9790 = fold_build2_loc (loc, code, type,
9791 eval_subst (loc, arg0, cval1, minval,
9795 /* All three of these results should be 0 or 1. Confirm they are.
9796 Then use those values to select the proper code to use. */
9798 if (TREE_CODE (high_result) == INTEGER_CST
9799 && TREE_CODE (equal_result) == INTEGER_CST
9800 && TREE_CODE (low_result) == INTEGER_CST)
9802 /* Make a 3-bit mask with the high-order bit being the
9803 value for `>', the next for '=', and the low for '<'. */
9804 switch ((integer_onep (high_result) * 4)
9805 + (integer_onep (equal_result) * 2)
9806 + integer_onep (low_result))
9810 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
9831 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
9836 tem = save_expr (build2 (code, type, cval1, cval2));
9837 SET_EXPR_LOCATION (tem, loc);
9840 return fold_build2_loc (loc, code, type, cval1, cval2);
9845 /* We can fold X/C1 op C2 where C1 and C2 are integer constants
9846 into a single range test. */
9847 if ((TREE_CODE (arg0) == TRUNC_DIV_EXPR
9848 || TREE_CODE (arg0) == EXACT_DIV_EXPR)
9849 && TREE_CODE (arg1) == INTEGER_CST
9850 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
9851 && !integer_zerop (TREE_OPERAND (arg0, 1))
9852 && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1))
9853 && !TREE_OVERFLOW (arg1))
9855 tem = fold_div_compare (loc, code, type, arg0, arg1);
9856 if (tem != NULL_TREE)
9860 /* Fold ~X op ~Y as Y op X. */
9861 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9862 && TREE_CODE (arg1) == BIT_NOT_EXPR)
9864 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9865 return fold_build2_loc (loc, code, type,
9866 fold_convert_loc (loc, cmp_type,
9867 TREE_OPERAND (arg1, 0)),
9868 TREE_OPERAND (arg0, 0));
9871 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
9872 if (TREE_CODE (arg0) == BIT_NOT_EXPR
9873 && TREE_CODE (arg1) == INTEGER_CST)
9875 tree cmp_type = TREE_TYPE (TREE_OPERAND (arg0, 0));
9876 return fold_build2_loc (loc, swap_tree_comparison (code), type,
9877 TREE_OPERAND (arg0, 0),
9878 fold_build1_loc (loc, BIT_NOT_EXPR, cmp_type,
9879 fold_convert_loc (loc, cmp_type, arg1)));
9886 /* Subroutine of fold_binary. Optimize complex multiplications of the
9887 form z * conj(z), as pow(realpart(z),2) + pow(imagpart(z),2). The
9888 argument EXPR represents the expression "z" of type TYPE. */
9891 fold_mult_zconjz (location_t loc, tree type, tree expr)
9893 tree itype = TREE_TYPE (type);
9894 tree rpart, ipart, tem;
9896 if (TREE_CODE (expr) == COMPLEX_EXPR)
9898 rpart = TREE_OPERAND (expr, 0);
9899 ipart = TREE_OPERAND (expr, 1);
9901 else if (TREE_CODE (expr) == COMPLEX_CST)
9903 rpart = TREE_REALPART (expr);
9904 ipart = TREE_IMAGPART (expr);
9908 expr = save_expr (expr);
9909 rpart = fold_build1_loc (loc, REALPART_EXPR, itype, expr);
9910 ipart = fold_build1_loc (loc, IMAGPART_EXPR, itype, expr);
9913 rpart = save_expr (rpart);
9914 ipart = save_expr (ipart);
9915 tem = fold_build2_loc (loc, PLUS_EXPR, itype,
9916 fold_build2_loc (loc, MULT_EXPR, itype, rpart, rpart),
9917 fold_build2_loc (loc, MULT_EXPR, itype, ipart, ipart));
9918 return fold_build2_loc (loc, COMPLEX_EXPR, type, tem,
9919 fold_convert_loc (loc, itype, integer_zero_node));
9923 /* Subroutine of fold_binary. If P is the value of EXPR, computes
9924 power-of-two M and (arbitrary) N such that M divides (P-N). This condition
9925 guarantees that P and N have the same least significant log2(M) bits.
9926 N is not otherwise constrained. In particular, N is not normalized to
9927 0 <= N < M as is common. In general, the precise value of P is unknown.
9928 M is chosen as large as possible such that constant N can be determined.
9930 Returns M and sets *RESIDUE to N.
9932 If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into
9933 account. This is not always possible due to PR 35705.
9936 static unsigned HOST_WIDE_INT
9937 get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue,
9938 bool allow_func_align)
9940 enum tree_code code;
9944 code = TREE_CODE (expr);
9945 if (code == ADDR_EXPR)
9947 expr = TREE_OPERAND (expr, 0);
9948 if (handled_component_p (expr))
9950 HOST_WIDE_INT bitsize, bitpos;
9952 enum machine_mode mode;
9953 int unsignedp, volatilep;
9955 expr = get_inner_reference (expr, &bitsize, &bitpos, &offset,
9956 &mode, &unsignedp, &volatilep, false);
9957 *residue = bitpos / BITS_PER_UNIT;
9960 if (TREE_CODE (offset) == INTEGER_CST)
9961 *residue += TREE_INT_CST_LOW (offset);
9963 /* We don't handle more complicated offset expressions. */
9969 && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL))
9970 return DECL_ALIGN_UNIT (expr);
9972 else if (code == POINTER_PLUS_EXPR)
9975 unsigned HOST_WIDE_INT modulus;
9976 enum tree_code inner_code;
9978 op0 = TREE_OPERAND (expr, 0);
9980 modulus = get_pointer_modulus_and_residue (op0, residue,
9983 op1 = TREE_OPERAND (expr, 1);
9985 inner_code = TREE_CODE (op1);
9986 if (inner_code == INTEGER_CST)
9988 *residue += TREE_INT_CST_LOW (op1);
9991 else if (inner_code == MULT_EXPR)
9993 op1 = TREE_OPERAND (op1, 1);
9994 if (TREE_CODE (op1) == INTEGER_CST)
9996 unsigned HOST_WIDE_INT align;
9998 /* Compute the greatest power-of-2 divisor of op1. */
9999 align = TREE_INT_CST_LOW (op1);
10002 /* If align is non-zero and less than *modulus, replace
10003 *modulus with align., If align is 0, then either op1 is 0
10004 or the greatest power-of-2 divisor of op1 doesn't fit in an
10005 unsigned HOST_WIDE_INT. In either case, no additional
10006 constraint is imposed. */
10008 modulus = MIN (modulus, align);
10015 /* If we get here, we were unable to determine anything useful about the
10021 /* Fold a binary expression of code CODE and type TYPE with operands
10022 OP0 and OP1. LOC is the location of the resulting expression.
10023 Return the folded expression if folding is successful. Otherwise,
10024 return NULL_TREE. */
10027 fold_binary_loc (location_t loc,
10028 enum tree_code code, tree type, tree op0, tree op1)
10030 enum tree_code_class kind = TREE_CODE_CLASS (code);
10031 tree arg0, arg1, tem;
10032 tree t1 = NULL_TREE;
10033 bool strict_overflow_p;
10035 gcc_assert (IS_EXPR_CODE_CLASS (kind)
10036 && TREE_CODE_LENGTH (code) == 2
10037 && op0 != NULL_TREE
10038 && op1 != NULL_TREE);
10043 /* Strip any conversions that don't change the mode. This is
10044 safe for every expression, except for a comparison expression
10045 because its signedness is derived from its operands. So, in
10046 the latter case, only strip conversions that don't change the
10047 signedness. MIN_EXPR/MAX_EXPR also need signedness of arguments
10050 Note that this is done as an internal manipulation within the
10051 constant folder, in order to find the simplest representation
10052 of the arguments so that their form can be studied. In any
10053 cases, the appropriate type conversions should be put back in
10054 the tree that will get out of the constant folder. */
10056 if (kind == tcc_comparison || code == MIN_EXPR || code == MAX_EXPR)
10058 STRIP_SIGN_NOPS (arg0);
10059 STRIP_SIGN_NOPS (arg1);
10067 /* Note that TREE_CONSTANT isn't enough: static var addresses are
10068 constant but we can't do arithmetic on them. */
10069 if ((TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
10070 || (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
10071 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == FIXED_CST)
10072 || (TREE_CODE (arg0) == FIXED_CST && TREE_CODE (arg1) == INTEGER_CST)
10073 || (TREE_CODE (arg0) == COMPLEX_CST && TREE_CODE (arg1) == COMPLEX_CST)
10074 || (TREE_CODE (arg0) == VECTOR_CST && TREE_CODE (arg1) == VECTOR_CST))
10076 if (kind == tcc_binary)
10078 /* Make sure type and arg0 have the same saturating flag. */
10079 gcc_assert (TYPE_SATURATING (type)
10080 == TYPE_SATURATING (TREE_TYPE (arg0)));
10081 tem = const_binop (code, arg0, arg1, 0);
10083 else if (kind == tcc_comparison)
10084 tem = fold_relational_const (code, type, arg0, arg1);
10088 if (tem != NULL_TREE)
10090 if (TREE_TYPE (tem) != type)
10091 tem = fold_convert_loc (loc, type, tem);
10096 /* If this is a commutative operation, and ARG0 is a constant, move it
10097 to ARG1 to reduce the number of tests below. */
10098 if (commutative_tree_code (code)
10099 && tree_swap_operands_p (arg0, arg1, true))
10100 return fold_build2_loc (loc, code, type, op1, op0);
10102 /* ARG0 is the first operand of EXPR, and ARG1 is the second operand.
10104 First check for cases where an arithmetic operation is applied to a
10105 compound, conditional, or comparison operation. Push the arithmetic
10106 operation inside the compound or conditional to see if any folding
10107 can then be done. Convert comparison to conditional for this purpose.
10108 The also optimizes non-constant cases that used to be done in
10111 Before we do that, see if this is a BIT_AND_EXPR or a BIT_IOR_EXPR,
10112 one of the operands is a comparison and the other is a comparison, a
10113 BIT_AND_EXPR with the constant 1, or a truth value. In that case, the
10114 code below would make the expression more complex. Change it to a
10115 TRUTH_{AND,OR}_EXPR. Likewise, convert a similar NE_EXPR to
10116 TRUTH_XOR_EXPR and an EQ_EXPR to the inversion of a TRUTH_XOR_EXPR. */
10118 if ((code == BIT_AND_EXPR || code == BIT_IOR_EXPR
10119 || code == EQ_EXPR || code == NE_EXPR)
10120 && ((truth_value_p (TREE_CODE (arg0))
10121 && (truth_value_p (TREE_CODE (arg1))
10122 || (TREE_CODE (arg1) == BIT_AND_EXPR
10123 && integer_onep (TREE_OPERAND (arg1, 1)))))
10124 || (truth_value_p (TREE_CODE (arg1))
10125 && (truth_value_p (TREE_CODE (arg0))
10126 || (TREE_CODE (arg0) == BIT_AND_EXPR
10127 && integer_onep (TREE_OPERAND (arg0, 1)))))))
10129 tem = fold_build2_loc (loc, code == BIT_AND_EXPR ? TRUTH_AND_EXPR
10130 : code == BIT_IOR_EXPR ? TRUTH_OR_EXPR
10133 fold_convert_loc (loc, boolean_type_node, arg0),
10134 fold_convert_loc (loc, boolean_type_node, arg1));
10136 if (code == EQ_EXPR)
10137 tem = invert_truthvalue_loc (loc, tem);
10139 return fold_convert_loc (loc, type, tem);
10142 if (TREE_CODE_CLASS (code) == tcc_binary
10143 || TREE_CODE_CLASS (code) == tcc_comparison)
10145 if (TREE_CODE (arg0) == COMPOUND_EXPR)
10147 tem = fold_build2_loc (loc, code, type,
10148 fold_convert_loc (loc, TREE_TYPE (op0),
10149 TREE_OPERAND (arg0, 1)), op1);
10150 protected_set_expr_location (tem, loc);
10151 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg0, 0), tem);
10152 goto fold_binary_exit;
10154 if (TREE_CODE (arg1) == COMPOUND_EXPR
10155 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
10157 tem = fold_build2_loc (loc, code, type, op0,
10158 fold_convert_loc (loc, TREE_TYPE (op1),
10159 TREE_OPERAND (arg1, 1)));
10160 protected_set_expr_location (tem, loc);
10161 tem = build2 (COMPOUND_EXPR, type, TREE_OPERAND (arg1, 0), tem);
10162 goto fold_binary_exit;
10165 if (TREE_CODE (arg0) == COND_EXPR || COMPARISON_CLASS_P (arg0))
10167 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
10169 /*cond_first_p=*/1);
10170 if (tem != NULL_TREE)
10174 if (TREE_CODE (arg1) == COND_EXPR || COMPARISON_CLASS_P (arg1))
10176 tem = fold_binary_op_with_conditional_arg (loc, code, type, op0, op1,
10178 /*cond_first_p=*/0);
10179 if (tem != NULL_TREE)
10186 case POINTER_PLUS_EXPR:
10187 /* 0 +p index -> (type)index */
10188 if (integer_zerop (arg0))
10189 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
10191 /* PTR +p 0 -> PTR */
10192 if (integer_zerop (arg1))
10193 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10195 /* INT +p INT -> (PTR)(INT + INT). Stripping types allows for this. */
10196 if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
10197 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
10198 return fold_convert_loc (loc, type,
10199 fold_build2_loc (loc, PLUS_EXPR, sizetype,
10200 fold_convert_loc (loc, sizetype,
10202 fold_convert_loc (loc, sizetype,
10205 /* index +p PTR -> PTR +p index */
10206 if (POINTER_TYPE_P (TREE_TYPE (arg1))
10207 && INTEGRAL_TYPE_P (TREE_TYPE (arg0)))
10208 return fold_build2_loc (loc, POINTER_PLUS_EXPR, type,
10209 fold_convert_loc (loc, type, arg1),
10210 fold_convert_loc (loc, sizetype, arg0));
10212 /* (PTR +p B) +p A -> PTR +p (B + A) */
10213 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10216 tree arg01 = fold_convert_loc (loc, sizetype, TREE_OPERAND (arg0, 1));
10217 tree arg00 = TREE_OPERAND (arg0, 0);
10218 inner = fold_build2_loc (loc, PLUS_EXPR, sizetype,
10219 arg01, fold_convert_loc (loc, sizetype, arg1));
10220 return fold_convert_loc (loc, type,
10221 fold_build2_loc (loc, POINTER_PLUS_EXPR,
10226 /* PTR_CST +p CST -> CST1 */
10227 if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
10228 return fold_build2_loc (loc, PLUS_EXPR, type, arg0,
10229 fold_convert_loc (loc, type, arg1));
10231 /* Try replacing &a[i1] +p c * i2 with &a[i1 + i2], if c is step
10232 of the array. Loop optimizer sometimes produce this type of
10234 if (TREE_CODE (arg0) == ADDR_EXPR)
10236 tem = try_move_mult_to_index (loc, arg0,
10237 fold_convert_loc (loc, sizetype, arg1));
10239 return fold_convert_loc (loc, type, tem);
10245 /* A + (-B) -> A - B */
10246 if (TREE_CODE (arg1) == NEGATE_EXPR)
10247 return fold_build2_loc (loc, MINUS_EXPR, type,
10248 fold_convert_loc (loc, type, arg0),
10249 fold_convert_loc (loc, type,
10250 TREE_OPERAND (arg1, 0)));
10251 /* (-A) + B -> B - A */
10252 if (TREE_CODE (arg0) == NEGATE_EXPR
10253 && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
10254 return fold_build2_loc (loc, MINUS_EXPR, type,
10255 fold_convert_loc (loc, type, arg1),
10256 fold_convert_loc (loc, type,
10257 TREE_OPERAND (arg0, 0)));
10259 if (INTEGRAL_TYPE_P (type))
10261 /* Convert ~A + 1 to -A. */
10262 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10263 && integer_onep (arg1))
10264 return fold_build1_loc (loc, NEGATE_EXPR, type,
10265 fold_convert_loc (loc, type,
10266 TREE_OPERAND (arg0, 0)));
10268 /* ~X + X is -1. */
10269 if (TREE_CODE (arg0) == BIT_NOT_EXPR
10270 && !TYPE_OVERFLOW_TRAPS (type))
10272 tree tem = TREE_OPERAND (arg0, 0);
10275 if (operand_equal_p (tem, arg1, 0))
10277 t1 = build_int_cst_type (type, -1);
10278 return omit_one_operand_loc (loc, type, t1, arg1);
10282 /* X + ~X is -1. */
10283 if (TREE_CODE (arg1) == BIT_NOT_EXPR
10284 && !TYPE_OVERFLOW_TRAPS (type))
10286 tree tem = TREE_OPERAND (arg1, 0);
10289 if (operand_equal_p (arg0, tem, 0))
10291 t1 = build_int_cst_type (type, -1);
10292 return omit_one_operand_loc (loc, type, t1, arg0);
10296 /* X + (X / CST) * -CST is X % CST. */
10297 if (TREE_CODE (arg1) == MULT_EXPR
10298 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10299 && operand_equal_p (arg0,
10300 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0))
10302 tree cst0 = TREE_OPERAND (TREE_OPERAND (arg1, 0), 1);
10303 tree cst1 = TREE_OPERAND (arg1, 1);
10304 tree sum = fold_binary_loc (loc, PLUS_EXPR, TREE_TYPE (cst1),
10306 if (sum && integer_zerop (sum))
10307 return fold_convert_loc (loc, type,
10308 fold_build2_loc (loc, TRUNC_MOD_EXPR,
10309 TREE_TYPE (arg0), arg0,
10314 /* Handle (A1 * C1) + (A2 * C2) with A1, A2 or C1, C2 being the
10315 same or one. Make sure type is not saturating.
10316 fold_plusminus_mult_expr will re-associate. */
10317 if ((TREE_CODE (arg0) == MULT_EXPR
10318 || TREE_CODE (arg1) == MULT_EXPR)
10319 && !TYPE_SATURATING (type)
10320 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10322 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10327 if (! FLOAT_TYPE_P (type))
10329 if (integer_zerop (arg1))
10330 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10332 /* If we are adding two BIT_AND_EXPR's, both of which are and'ing
10333 with a constant, and the two constants have no bits in common,
10334 we should treat this as a BIT_IOR_EXPR since this may produce more
10335 simplifications. */
10336 if (TREE_CODE (arg0) == BIT_AND_EXPR
10337 && TREE_CODE (arg1) == BIT_AND_EXPR
10338 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
10339 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
10340 && integer_zerop (const_binop (BIT_AND_EXPR,
10341 TREE_OPERAND (arg0, 1),
10342 TREE_OPERAND (arg1, 1), 0)))
10344 code = BIT_IOR_EXPR;
10348 /* Reassociate (plus (plus (mult) (foo)) (mult)) as
10349 (plus (plus (mult) (mult)) (foo)) so that we can
10350 take advantage of the factoring cases below. */
10351 if (((TREE_CODE (arg0) == PLUS_EXPR
10352 || TREE_CODE (arg0) == MINUS_EXPR)
10353 && TREE_CODE (arg1) == MULT_EXPR)
10354 || ((TREE_CODE (arg1) == PLUS_EXPR
10355 || TREE_CODE (arg1) == MINUS_EXPR)
10356 && TREE_CODE (arg0) == MULT_EXPR))
10358 tree parg0, parg1, parg, marg;
10359 enum tree_code pcode;
10361 if (TREE_CODE (arg1) == MULT_EXPR)
10362 parg = arg0, marg = arg1;
10364 parg = arg1, marg = arg0;
10365 pcode = TREE_CODE (parg);
10366 parg0 = TREE_OPERAND (parg, 0);
10367 parg1 = TREE_OPERAND (parg, 1);
10368 STRIP_NOPS (parg0);
10369 STRIP_NOPS (parg1);
10371 if (TREE_CODE (parg0) == MULT_EXPR
10372 && TREE_CODE (parg1) != MULT_EXPR)
10373 return fold_build2_loc (loc, pcode, type,
10374 fold_build2_loc (loc, PLUS_EXPR, type,
10375 fold_convert_loc (loc, type,
10377 fold_convert_loc (loc, type,
10379 fold_convert_loc (loc, type, parg1));
10380 if (TREE_CODE (parg0) != MULT_EXPR
10381 && TREE_CODE (parg1) == MULT_EXPR)
10383 fold_build2_loc (loc, PLUS_EXPR, type,
10384 fold_convert_loc (loc, type, parg0),
10385 fold_build2_loc (loc, pcode, type,
10386 fold_convert_loc (loc, type, marg),
10387 fold_convert_loc (loc, type,
10393 /* See if ARG1 is zero and X + ARG1 reduces to X. */
10394 if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 0))
10395 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10397 /* Likewise if the operands are reversed. */
10398 if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10399 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
10401 /* Convert X + -C into X - C. */
10402 if (TREE_CODE (arg1) == REAL_CST
10403 && REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1)))
10405 tem = fold_negate_const (arg1, type);
10406 if (!TREE_OVERFLOW (arg1) || !flag_trapping_math)
10407 return fold_build2_loc (loc, MINUS_EXPR, type,
10408 fold_convert_loc (loc, type, arg0),
10409 fold_convert_loc (loc, type, tem));
10412 /* Fold __complex__ ( x, 0 ) + __complex__ ( 0, y )
10413 to __complex__ ( x, y ). This is not the same for SNaNs or
10414 if signed zeros are involved. */
10415 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10416 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10417 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10419 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10420 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10421 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10422 bool arg0rz = false, arg0iz = false;
10423 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10424 || (arg0i && (arg0iz = real_zerop (arg0i))))
10426 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10427 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10428 if (arg0rz && arg1i && real_zerop (arg1i))
10430 tree rp = arg1r ? arg1r
10431 : build1 (REALPART_EXPR, rtype, arg1);
10432 tree ip = arg0i ? arg0i
10433 : build1 (IMAGPART_EXPR, rtype, arg0);
10434 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10436 else if (arg0iz && arg1r && real_zerop (arg1r))
10438 tree rp = arg0r ? arg0r
10439 : build1 (REALPART_EXPR, rtype, arg0);
10440 tree ip = arg1i ? arg1i
10441 : build1 (IMAGPART_EXPR, rtype, arg1);
10442 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10447 if (flag_unsafe_math_optimizations
10448 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10449 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10450 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10453 /* Convert x+x into x*2.0. */
10454 if (operand_equal_p (arg0, arg1, 0)
10455 && SCALAR_FLOAT_TYPE_P (type))
10456 return fold_build2_loc (loc, MULT_EXPR, type, arg0,
10457 build_real (type, dconst2));
10459 /* Convert a + (b*c + d*e) into (a + b*c) + d*e.
10460 We associate floats only if the user has specified
10461 -fassociative-math. */
10462 if (flag_associative_math
10463 && TREE_CODE (arg1) == PLUS_EXPR
10464 && TREE_CODE (arg0) != MULT_EXPR)
10466 tree tree10 = TREE_OPERAND (arg1, 0);
10467 tree tree11 = TREE_OPERAND (arg1, 1);
10468 if (TREE_CODE (tree11) == MULT_EXPR
10469 && TREE_CODE (tree10) == MULT_EXPR)
10472 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, arg0, tree10);
10473 return fold_build2_loc (loc, PLUS_EXPR, type, tree0, tree11);
10476 /* Convert (b*c + d*e) + a into b*c + (d*e +a).
10477 We associate floats only if the user has specified
10478 -fassociative-math. */
10479 if (flag_associative_math
10480 && TREE_CODE (arg0) == PLUS_EXPR
10481 && TREE_CODE (arg1) != MULT_EXPR)
10483 tree tree00 = TREE_OPERAND (arg0, 0);
10484 tree tree01 = TREE_OPERAND (arg0, 1);
10485 if (TREE_CODE (tree01) == MULT_EXPR
10486 && TREE_CODE (tree00) == MULT_EXPR)
10489 tree0 = fold_build2_loc (loc, PLUS_EXPR, type, tree01, arg1);
10490 return fold_build2_loc (loc, PLUS_EXPR, type, tree00, tree0);
10496 /* (A << C1) + (A >> C2) if A is unsigned and C1+C2 is the size of A
10497 is a rotate of A by C1 bits. */
10498 /* (A << B) + (A >> (Z - B)) if A is unsigned and Z is the size of A
10499 is a rotate of A by B bits. */
10501 enum tree_code code0, code1;
10503 code0 = TREE_CODE (arg0);
10504 code1 = TREE_CODE (arg1);
10505 if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
10506 || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
10507 && operand_equal_p (TREE_OPERAND (arg0, 0),
10508 TREE_OPERAND (arg1, 0), 0)
10509 && (rtype = TREE_TYPE (TREE_OPERAND (arg0, 0)),
10510 TYPE_UNSIGNED (rtype))
10511 /* Only create rotates in complete modes. Other cases are not
10512 expanded properly. */
10513 && TYPE_PRECISION (rtype) == GET_MODE_PRECISION (TYPE_MODE (rtype)))
10515 tree tree01, tree11;
10516 enum tree_code code01, code11;
10518 tree01 = TREE_OPERAND (arg0, 1);
10519 tree11 = TREE_OPERAND (arg1, 1);
10520 STRIP_NOPS (tree01);
10521 STRIP_NOPS (tree11);
10522 code01 = TREE_CODE (tree01);
10523 code11 = TREE_CODE (tree11);
10524 if (code01 == INTEGER_CST
10525 && code11 == INTEGER_CST
10526 && TREE_INT_CST_HIGH (tree01) == 0
10527 && TREE_INT_CST_HIGH (tree11) == 0
10528 && ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
10529 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
10531 tem = build2 (LROTATE_EXPR,
10532 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10533 TREE_OPERAND (arg0, 0),
10534 code0 == LSHIFT_EXPR
10535 ? tree01 : tree11);
10536 SET_EXPR_LOCATION (tem, loc);
10537 return fold_convert_loc (loc, type, tem);
10539 else if (code11 == MINUS_EXPR)
10541 tree tree110, tree111;
10542 tree110 = TREE_OPERAND (tree11, 0);
10543 tree111 = TREE_OPERAND (tree11, 1);
10544 STRIP_NOPS (tree110);
10545 STRIP_NOPS (tree111);
10546 if (TREE_CODE (tree110) == INTEGER_CST
10547 && 0 == compare_tree_int (tree110,
10549 (TREE_TYPE (TREE_OPERAND
10551 && operand_equal_p (tree01, tree111, 0))
10553 fold_convert_loc (loc, type,
10554 build2 ((code0 == LSHIFT_EXPR
10557 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10558 TREE_OPERAND (arg0, 0), tree01));
10560 else if (code01 == MINUS_EXPR)
10562 tree tree010, tree011;
10563 tree010 = TREE_OPERAND (tree01, 0);
10564 tree011 = TREE_OPERAND (tree01, 1);
10565 STRIP_NOPS (tree010);
10566 STRIP_NOPS (tree011);
10567 if (TREE_CODE (tree010) == INTEGER_CST
10568 && 0 == compare_tree_int (tree010,
10570 (TREE_TYPE (TREE_OPERAND
10572 && operand_equal_p (tree11, tree011, 0))
10573 return fold_convert_loc
10575 build2 ((code0 != LSHIFT_EXPR
10578 TREE_TYPE (TREE_OPERAND (arg0, 0)),
10579 TREE_OPERAND (arg0, 0), tree11));
10585 /* In most languages, can't associate operations on floats through
10586 parentheses. Rather than remember where the parentheses were, we
10587 don't associate floats at all, unless the user has specified
10588 -fassociative-math.
10589 And, we need to make sure type is not saturating. */
10591 if ((! FLOAT_TYPE_P (type) || flag_associative_math)
10592 && !TYPE_SATURATING (type))
10594 tree var0, con0, lit0, minus_lit0;
10595 tree var1, con1, lit1, minus_lit1;
10598 /* Split both trees into variables, constants, and literals. Then
10599 associate each group together, the constants with literals,
10600 then the result with variables. This increases the chances of
10601 literals being recombined later and of generating relocatable
10602 expressions for the sum of a constant and literal. */
10603 var0 = split_tree (arg0, code, &con0, &lit0, &minus_lit0, 0);
10604 var1 = split_tree (arg1, code, &con1, &lit1, &minus_lit1,
10605 code == MINUS_EXPR);
10607 /* With undefined overflow we can only associate constants
10608 with one variable. */
10609 if (((POINTER_TYPE_P (type) && POINTER_TYPE_OVERFLOW_UNDEFINED)
10610 || (INTEGRAL_TYPE_P (type) && !TYPE_OVERFLOW_WRAPS (type)))
10616 if (TREE_CODE (tmp0) == NEGATE_EXPR)
10617 tmp0 = TREE_OPERAND (tmp0, 0);
10618 if (TREE_CODE (tmp1) == NEGATE_EXPR)
10619 tmp1 = TREE_OPERAND (tmp1, 0);
10620 /* The only case we can still associate with two variables
10621 is if they are the same, modulo negation. */
10622 if (!operand_equal_p (tmp0, tmp1, 0))
10626 /* Only do something if we found more than two objects. Otherwise,
10627 nothing has changed and we risk infinite recursion. */
10629 && (2 < ((var0 != 0) + (var1 != 0)
10630 + (con0 != 0) + (con1 != 0)
10631 + (lit0 != 0) + (lit1 != 0)
10632 + (minus_lit0 != 0) + (minus_lit1 != 0))))
10634 /* Recombine MINUS_EXPR operands by using PLUS_EXPR. */
10635 if (code == MINUS_EXPR)
10638 var0 = associate_trees (loc, var0, var1, code, type);
10639 con0 = associate_trees (loc, con0, con1, code, type);
10640 lit0 = associate_trees (loc, lit0, lit1, code, type);
10641 minus_lit0 = associate_trees (loc, minus_lit0, minus_lit1, code, type);
10643 /* Preserve the MINUS_EXPR if the negative part of the literal is
10644 greater than the positive part. Otherwise, the multiplicative
10645 folding code (i.e extract_muldiv) may be fooled in case
10646 unsigned constants are subtracted, like in the following
10647 example: ((X*2 + 4) - 8U)/2. */
10648 if (minus_lit0 && lit0)
10650 if (TREE_CODE (lit0) == INTEGER_CST
10651 && TREE_CODE (minus_lit0) == INTEGER_CST
10652 && tree_int_cst_lt (lit0, minus_lit0))
10654 minus_lit0 = associate_trees (loc, minus_lit0, lit0,
10660 lit0 = associate_trees (loc, lit0, minus_lit0,
10669 fold_convert_loc (loc, type,
10670 associate_trees (loc, var0, minus_lit0,
10671 MINUS_EXPR, type));
10674 con0 = associate_trees (loc, con0, minus_lit0,
10677 fold_convert_loc (loc, type,
10678 associate_trees (loc, var0, con0,
10683 con0 = associate_trees (loc, con0, lit0, code, type);
10685 fold_convert_loc (loc, type, associate_trees (loc, var0, con0,
10693 /* Pointer simplifications for subtraction, simple reassociations. */
10694 if (POINTER_TYPE_P (TREE_TYPE (arg1)) && POINTER_TYPE_P (TREE_TYPE (arg0)))
10696 /* (PTR0 p+ A) - (PTR1 p+ B) -> (PTR0 - PTR1) + (A - B) */
10697 if (TREE_CODE (arg0) == POINTER_PLUS_EXPR
10698 && TREE_CODE (arg1) == POINTER_PLUS_EXPR)
10700 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10701 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10702 tree arg10 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
10703 tree arg11 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
10704 return fold_build2_loc (loc, PLUS_EXPR, type,
10705 fold_build2_loc (loc, MINUS_EXPR, type,
10707 fold_build2_loc (loc, MINUS_EXPR, type,
10710 /* (PTR0 p+ A) - PTR1 -> (PTR0 - PTR1) + A, assuming PTR0 - PTR1 simplifies. */
10711 else if (TREE_CODE (arg0) == POINTER_PLUS_EXPR)
10713 tree arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
10714 tree arg01 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
10715 tree tmp = fold_binary_loc (loc, MINUS_EXPR, type, arg00,
10716 fold_convert_loc (loc, type, arg1));
10718 return fold_build2_loc (loc, PLUS_EXPR, type, tmp, arg01);
10721 /* A - (-B) -> A + B */
10722 if (TREE_CODE (arg1) == NEGATE_EXPR)
10723 return fold_build2_loc (loc, PLUS_EXPR, type, op0,
10724 fold_convert_loc (loc, type,
10725 TREE_OPERAND (arg1, 0)));
10726 /* (-A) - B -> (-B) - A where B is easily negated and we can swap. */
10727 if (TREE_CODE (arg0) == NEGATE_EXPR
10728 && (FLOAT_TYPE_P (type)
10729 || INTEGRAL_TYPE_P (type))
10730 && negate_expr_p (arg1)
10731 && reorder_operands_p (arg0, arg1))
10732 return fold_build2_loc (loc, MINUS_EXPR, type,
10733 fold_convert_loc (loc, type,
10734 negate_expr (arg1)),
10735 fold_convert_loc (loc, type,
10736 TREE_OPERAND (arg0, 0)));
10737 /* Convert -A - 1 to ~A. */
10738 if (INTEGRAL_TYPE_P (type)
10739 && TREE_CODE (arg0) == NEGATE_EXPR
10740 && integer_onep (arg1)
10741 && !TYPE_OVERFLOW_TRAPS (type))
10742 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
10743 fold_convert_loc (loc, type,
10744 TREE_OPERAND (arg0, 0)));
10746 /* Convert -1 - A to ~A. */
10747 if (INTEGRAL_TYPE_P (type)
10748 && integer_all_onesp (arg0))
10749 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op1);
10752 /* X - (X / CST) * CST is X % CST. */
10753 if (INTEGRAL_TYPE_P (type)
10754 && TREE_CODE (arg1) == MULT_EXPR
10755 && TREE_CODE (TREE_OPERAND (arg1, 0)) == TRUNC_DIV_EXPR
10756 && operand_equal_p (arg0,
10757 TREE_OPERAND (TREE_OPERAND (arg1, 0), 0), 0)
10758 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg1, 0), 1),
10759 TREE_OPERAND (arg1, 1), 0))
10761 fold_convert_loc (loc, type,
10762 fold_build2_loc (loc, TRUNC_MOD_EXPR, TREE_TYPE (arg0),
10763 arg0, TREE_OPERAND (arg1, 1)));
10765 if (! FLOAT_TYPE_P (type))
10767 if (integer_zerop (arg0))
10768 return negate_expr (fold_convert_loc (loc, type, arg1));
10769 if (integer_zerop (arg1))
10770 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10772 /* Fold A - (A & B) into ~B & A. */
10773 if (!TREE_SIDE_EFFECTS (arg0)
10774 && TREE_CODE (arg1) == BIT_AND_EXPR)
10776 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0))
10778 tree arg10 = fold_convert_loc (loc, type,
10779 TREE_OPERAND (arg1, 0));
10780 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10781 fold_build1_loc (loc, BIT_NOT_EXPR,
10783 fold_convert_loc (loc, type, arg0));
10785 if (operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
10787 tree arg11 = fold_convert_loc (loc,
10788 type, TREE_OPERAND (arg1, 1));
10789 return fold_build2_loc (loc, BIT_AND_EXPR, type,
10790 fold_build1_loc (loc, BIT_NOT_EXPR,
10792 fold_convert_loc (loc, type, arg0));
10796 /* Fold (A & ~B) - (A & B) into (A ^ B) - B, where B is
10797 any power of 2 minus 1. */
10798 if (TREE_CODE (arg0) == BIT_AND_EXPR
10799 && TREE_CODE (arg1) == BIT_AND_EXPR
10800 && operand_equal_p (TREE_OPERAND (arg0, 0),
10801 TREE_OPERAND (arg1, 0), 0))
10803 tree mask0 = TREE_OPERAND (arg0, 1);
10804 tree mask1 = TREE_OPERAND (arg1, 1);
10805 tree tem = fold_build1_loc (loc, BIT_NOT_EXPR, type, mask0);
10807 if (operand_equal_p (tem, mask1, 0))
10809 tem = fold_build2_loc (loc, BIT_XOR_EXPR, type,
10810 TREE_OPERAND (arg0, 0), mask1);
10811 return fold_build2_loc (loc, MINUS_EXPR, type, tem, mask1);
10816 /* See if ARG1 is zero and X - ARG1 reduces to X. */
10817 else if (fold_real_zero_addition_p (TREE_TYPE (arg0), arg1, 1))
10818 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10820 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
10821 ARG0 is zero and X + ARG0 reduces to X, since that would mean
10822 (-ARG1 + ARG0) reduces to -ARG1. */
10823 else if (fold_real_zero_addition_p (TREE_TYPE (arg1), arg0, 0))
10824 return negate_expr (fold_convert_loc (loc, type, arg1));
10826 /* Fold __complex__ ( x, 0 ) - __complex__ ( 0, y ) to
10827 __complex__ ( x, -y ). This is not the same for SNaNs or if
10828 signed zeros are involved. */
10829 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
10830 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
10831 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
10833 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
10834 tree arg0r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg0);
10835 tree arg0i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg0);
10836 bool arg0rz = false, arg0iz = false;
10837 if ((arg0r && (arg0rz = real_zerop (arg0r)))
10838 || (arg0i && (arg0iz = real_zerop (arg0i))))
10840 tree arg1r = fold_unary_loc (loc, REALPART_EXPR, rtype, arg1);
10841 tree arg1i = fold_unary_loc (loc, IMAGPART_EXPR, rtype, arg1);
10842 if (arg0rz && arg1i && real_zerop (arg1i))
10844 tree rp = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10846 : build1 (REALPART_EXPR, rtype, arg1));
10847 tree ip = arg0i ? arg0i
10848 : build1 (IMAGPART_EXPR, rtype, arg0);
10849 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10851 else if (arg0iz && arg1r && real_zerop (arg1r))
10853 tree rp = arg0r ? arg0r
10854 : build1 (REALPART_EXPR, rtype, arg0);
10855 tree ip = fold_build1_loc (loc, NEGATE_EXPR, rtype,
10857 : build1 (IMAGPART_EXPR, rtype, arg1));
10858 return fold_build2_loc (loc, COMPLEX_EXPR, type, rp, ip);
10863 /* Fold &x - &x. This can happen from &x.foo - &x.
10864 This is unsafe for certain floats even in non-IEEE formats.
10865 In IEEE, it is unsafe because it does wrong for NaNs.
10866 Also note that operand_equal_p is always false if an operand
10869 if ((!FLOAT_TYPE_P (type) || !HONOR_NANS (TYPE_MODE (type)))
10870 && operand_equal_p (arg0, arg1, 0))
10871 return fold_convert_loc (loc, type, integer_zero_node);
10873 /* A - B -> A + (-B) if B is easily negatable. */
10874 if (negate_expr_p (arg1)
10875 && ((FLOAT_TYPE_P (type)
10876 /* Avoid this transformation if B is a positive REAL_CST. */
10877 && (TREE_CODE (arg1) != REAL_CST
10878 || REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg1))))
10879 || INTEGRAL_TYPE_P (type)))
10880 return fold_build2_loc (loc, PLUS_EXPR, type,
10881 fold_convert_loc (loc, type, arg0),
10882 fold_convert_loc (loc, type,
10883 negate_expr (arg1)));
10885 /* Try folding difference of addresses. */
10887 HOST_WIDE_INT diff;
10889 if ((TREE_CODE (arg0) == ADDR_EXPR
10890 || TREE_CODE (arg1) == ADDR_EXPR)
10891 && ptr_difference_const (arg0, arg1, &diff))
10892 return build_int_cst_type (type, diff);
10895 /* Fold &a[i] - &a[j] to i-j. */
10896 if (TREE_CODE (arg0) == ADDR_EXPR
10897 && TREE_CODE (TREE_OPERAND (arg0, 0)) == ARRAY_REF
10898 && TREE_CODE (arg1) == ADDR_EXPR
10899 && TREE_CODE (TREE_OPERAND (arg1, 0)) == ARRAY_REF)
10901 tree aref0 = TREE_OPERAND (arg0, 0);
10902 tree aref1 = TREE_OPERAND (arg1, 0);
10903 if (operand_equal_p (TREE_OPERAND (aref0, 0),
10904 TREE_OPERAND (aref1, 0), 0))
10906 tree op0 = fold_convert_loc (loc, type, TREE_OPERAND (aref0, 1));
10907 tree op1 = fold_convert_loc (loc, type, TREE_OPERAND (aref1, 1));
10908 tree esz = array_ref_element_size (aref0);
10909 tree diff = build2 (MINUS_EXPR, type, op0, op1);
10910 return fold_build2_loc (loc, MULT_EXPR, type, diff,
10911 fold_convert_loc (loc, type, esz));
10916 if (FLOAT_TYPE_P (type)
10917 && flag_unsafe_math_optimizations
10918 && (TREE_CODE (arg0) == RDIV_EXPR || TREE_CODE (arg0) == MULT_EXPR)
10919 && (TREE_CODE (arg1) == RDIV_EXPR || TREE_CODE (arg1) == MULT_EXPR)
10920 && (tem = distribute_real_division (loc, code, type, arg0, arg1)))
10923 /* Handle (A1 * C1) - (A2 * C2) with A1, A2 or C1, C2 being the
10924 same or one. Make sure type is not saturating.
10925 fold_plusminus_mult_expr will re-associate. */
10926 if ((TREE_CODE (arg0) == MULT_EXPR
10927 || TREE_CODE (arg1) == MULT_EXPR)
10928 && !TYPE_SATURATING (type)
10929 && (!FLOAT_TYPE_P (type) || flag_associative_math))
10931 tree tem = fold_plusminus_mult_expr (loc, code, type, arg0, arg1);
10939 /* (-A) * (-B) -> A * B */
10940 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
10941 return fold_build2_loc (loc, MULT_EXPR, type,
10942 fold_convert_loc (loc, type,
10943 TREE_OPERAND (arg0, 0)),
10944 fold_convert_loc (loc, type,
10945 negate_expr (arg1)));
10946 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
10947 return fold_build2_loc (loc, MULT_EXPR, type,
10948 fold_convert_loc (loc, type,
10949 negate_expr (arg0)),
10950 fold_convert_loc (loc, type,
10951 TREE_OPERAND (arg1, 0)));
10953 if (! FLOAT_TYPE_P (type))
10955 if (integer_zerop (arg1))
10956 return omit_one_operand_loc (loc, type, arg1, arg0);
10957 if (integer_onep (arg1))
10958 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
10959 /* Transform x * -1 into -x. Make sure to do the negation
10960 on the original operand with conversions not stripped
10961 because we can only strip non-sign-changing conversions. */
10962 if (integer_all_onesp (arg1))
10963 return fold_convert_loc (loc, type, negate_expr (op0));
10964 /* Transform x * -C into -x * C if x is easily negatable. */
10965 if (TREE_CODE (arg1) == INTEGER_CST
10966 && tree_int_cst_sgn (arg1) == -1
10967 && negate_expr_p (arg0)
10968 && (tem = negate_expr (arg1)) != arg1
10969 && !TREE_OVERFLOW (tem))
10970 return fold_build2_loc (loc, MULT_EXPR, type,
10971 fold_convert_loc (loc, type,
10972 negate_expr (arg0)),
10975 /* (a * (1 << b)) is (a << b) */
10976 if (TREE_CODE (arg1) == LSHIFT_EXPR
10977 && integer_onep (TREE_OPERAND (arg1, 0)))
10978 return fold_build2_loc (loc, LSHIFT_EXPR, type, op0,
10979 TREE_OPERAND (arg1, 1));
10980 if (TREE_CODE (arg0) == LSHIFT_EXPR
10981 && integer_onep (TREE_OPERAND (arg0, 0)))
10982 return fold_build2_loc (loc, LSHIFT_EXPR, type, op1,
10983 TREE_OPERAND (arg0, 1));
10985 /* (A + A) * C -> A * 2 * C */
10986 if (TREE_CODE (arg0) == PLUS_EXPR
10987 && TREE_CODE (arg1) == INTEGER_CST
10988 && operand_equal_p (TREE_OPERAND (arg0, 0),
10989 TREE_OPERAND (arg0, 1), 0))
10990 return fold_build2_loc (loc, MULT_EXPR, type,
10991 omit_one_operand_loc (loc, type,
10992 TREE_OPERAND (arg0, 0),
10993 TREE_OPERAND (arg0, 1)),
10994 fold_build2_loc (loc, MULT_EXPR, type,
10995 build_int_cst (type, 2) , arg1));
10997 strict_overflow_p = false;
10998 if (TREE_CODE (arg1) == INTEGER_CST
10999 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
11000 &strict_overflow_p)))
11002 if (strict_overflow_p)
11003 fold_overflow_warning (("assuming signed overflow does not "
11004 "occur when simplifying "
11006 WARN_STRICT_OVERFLOW_MISC);
11007 return fold_convert_loc (loc, type, tem);
11010 /* Optimize z * conj(z) for integer complex numbers. */
11011 if (TREE_CODE (arg0) == CONJ_EXPR
11012 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11013 return fold_mult_zconjz (loc, type, arg1);
11014 if (TREE_CODE (arg1) == CONJ_EXPR
11015 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11016 return fold_mult_zconjz (loc, type, arg0);
11020 /* Maybe fold x * 0 to 0. The expressions aren't the same
11021 when x is NaN, since x * 0 is also NaN. Nor are they the
11022 same in modes with signed zeros, since multiplying a
11023 negative value by 0 gives -0, not +0. */
11024 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11025 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11026 && real_zerop (arg1))
11027 return omit_one_operand_loc (loc, type, arg1, arg0);
11028 /* In IEEE floating point, x*1 is not equivalent to x for snans.
11029 Likewise for complex arithmetic with signed zeros. */
11030 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11031 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11032 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
11033 && real_onep (arg1))
11034 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11036 /* Transform x * -1.0 into -x. */
11037 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11038 && (!HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11039 || !COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0)))
11040 && real_minus_onep (arg1))
11041 return fold_convert_loc (loc, type, negate_expr (arg0));
11043 /* Convert (C1/X)*C2 into (C1*C2)/X. This transformation may change
11044 the result for floating point types due to rounding so it is applied
11045 only if -fassociative-math was specify. */
11046 if (flag_associative_math
11047 && TREE_CODE (arg0) == RDIV_EXPR
11048 && TREE_CODE (arg1) == REAL_CST
11049 && TREE_CODE (TREE_OPERAND (arg0, 0)) == REAL_CST)
11051 tree tem = const_binop (MULT_EXPR, TREE_OPERAND (arg0, 0),
11054 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11055 TREE_OPERAND (arg0, 1));
11058 /* Strip sign operations from X in X*X, i.e. -Y*-Y -> Y*Y. */
11059 if (operand_equal_p (arg0, arg1, 0))
11061 tree tem = fold_strip_sign_ops (arg0);
11062 if (tem != NULL_TREE)
11064 tem = fold_convert_loc (loc, type, tem);
11065 return fold_build2_loc (loc, MULT_EXPR, type, tem, tem);
11069 /* Fold z * +-I to __complex__ (-+__imag z, +-__real z).
11070 This is not the same for NaNs or if signed zeros are
11072 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11073 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg0)))
11074 && COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11075 && TREE_CODE (arg1) == COMPLEX_CST
11076 && real_zerop (TREE_REALPART (arg1)))
11078 tree rtype = TREE_TYPE (TREE_TYPE (arg0));
11079 if (real_onep (TREE_IMAGPART (arg1)))
11081 fold_build2_loc (loc, COMPLEX_EXPR, type,
11082 negate_expr (fold_build1_loc (loc, IMAGPART_EXPR,
11084 fold_build1_loc (loc, REALPART_EXPR, rtype, arg0));
11085 else if (real_minus_onep (TREE_IMAGPART (arg1)))
11087 fold_build2_loc (loc, COMPLEX_EXPR, type,
11088 fold_build1_loc (loc, IMAGPART_EXPR, rtype, arg0),
11089 negate_expr (fold_build1_loc (loc, REALPART_EXPR,
11093 /* Optimize z * conj(z) for floating point complex numbers.
11094 Guarded by flag_unsafe_math_optimizations as non-finite
11095 imaginary components don't produce scalar results. */
11096 if (flag_unsafe_math_optimizations
11097 && TREE_CODE (arg0) == CONJ_EXPR
11098 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11099 return fold_mult_zconjz (loc, type, arg1);
11100 if (flag_unsafe_math_optimizations
11101 && TREE_CODE (arg1) == CONJ_EXPR
11102 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11103 return fold_mult_zconjz (loc, type, arg0);
11105 if (flag_unsafe_math_optimizations)
11107 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11108 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11110 /* Optimizations of root(...)*root(...). */
11111 if (fcode0 == fcode1 && BUILTIN_ROOT_P (fcode0))
11114 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11115 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11117 /* Optimize sqrt(x)*sqrt(x) as x. */
11118 if (BUILTIN_SQRT_P (fcode0)
11119 && operand_equal_p (arg00, arg10, 0)
11120 && ! HONOR_SNANS (TYPE_MODE (type)))
11123 /* Optimize root(x)*root(y) as root(x*y). */
11124 rootfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11125 arg = fold_build2_loc (loc, MULT_EXPR, type, arg00, arg10);
11126 return build_call_expr_loc (loc, rootfn, 1, arg);
11129 /* Optimize expN(x)*expN(y) as expN(x+y). */
11130 if (fcode0 == fcode1 && BUILTIN_EXPONENT_P (fcode0))
11132 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11133 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
11134 CALL_EXPR_ARG (arg0, 0),
11135 CALL_EXPR_ARG (arg1, 0));
11136 return build_call_expr_loc (loc, expfn, 1, arg);
11139 /* Optimizations of pow(...)*pow(...). */
11140 if ((fcode0 == BUILT_IN_POW && fcode1 == BUILT_IN_POW)
11141 || (fcode0 == BUILT_IN_POWF && fcode1 == BUILT_IN_POWF)
11142 || (fcode0 == BUILT_IN_POWL && fcode1 == BUILT_IN_POWL))
11144 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11145 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11146 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11147 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11149 /* Optimize pow(x,y)*pow(z,y) as pow(x*z,y). */
11150 if (operand_equal_p (arg01, arg11, 0))
11152 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11153 tree arg = fold_build2_loc (loc, MULT_EXPR, type,
11155 return build_call_expr_loc (loc, powfn, 2, arg, arg01);
11158 /* Optimize pow(x,y)*pow(x,z) as pow(x,y+z). */
11159 if (operand_equal_p (arg00, arg10, 0))
11161 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11162 tree arg = fold_build2_loc (loc, PLUS_EXPR, type,
11164 return build_call_expr_loc (loc, powfn, 2, arg00, arg);
11168 /* Optimize tan(x)*cos(x) as sin(x). */
11169 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_COS)
11170 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_COSF)
11171 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_COSL)
11172 || (fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_TAN)
11173 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_TANF)
11174 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_TANL))
11175 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11176 CALL_EXPR_ARG (arg1, 0), 0))
11178 tree sinfn = mathfn_built_in (type, BUILT_IN_SIN);
11180 if (sinfn != NULL_TREE)
11181 return build_call_expr_loc (loc, sinfn, 1,
11182 CALL_EXPR_ARG (arg0, 0));
11185 /* Optimize x*pow(x,c) as pow(x,c+1). */
11186 if (fcode1 == BUILT_IN_POW
11187 || fcode1 == BUILT_IN_POWF
11188 || fcode1 == BUILT_IN_POWL)
11190 tree arg10 = CALL_EXPR_ARG (arg1, 0);
11191 tree arg11 = CALL_EXPR_ARG (arg1, 1);
11192 if (TREE_CODE (arg11) == REAL_CST
11193 && !TREE_OVERFLOW (arg11)
11194 && operand_equal_p (arg0, arg10, 0))
11196 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
11200 c = TREE_REAL_CST (arg11);
11201 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
11202 arg = build_real (type, c);
11203 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
11207 /* Optimize pow(x,c)*x as pow(x,c+1). */
11208 if (fcode0 == BUILT_IN_POW
11209 || fcode0 == BUILT_IN_POWF
11210 || fcode0 == BUILT_IN_POWL)
11212 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11213 tree arg01 = CALL_EXPR_ARG (arg0, 1);
11214 if (TREE_CODE (arg01) == REAL_CST
11215 && !TREE_OVERFLOW (arg01)
11216 && operand_equal_p (arg1, arg00, 0))
11218 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
11222 c = TREE_REAL_CST (arg01);
11223 real_arithmetic (&c, PLUS_EXPR, &c, &dconst1);
11224 arg = build_real (type, c);
11225 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
11229 /* Optimize x*x as pow(x,2.0), which is expanded as x*x. */
11230 if (optimize_function_for_speed_p (cfun)
11231 && operand_equal_p (arg0, arg1, 0))
11233 tree powfn = mathfn_built_in (type, BUILT_IN_POW);
11237 tree arg = build_real (type, dconst2);
11238 return build_call_expr_loc (loc, powfn, 2, arg0, arg);
11247 if (integer_all_onesp (arg1))
11248 return omit_one_operand_loc (loc, type, arg1, arg0);
11249 if (integer_zerop (arg1))
11250 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11251 if (operand_equal_p (arg0, arg1, 0))
11252 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11254 /* ~X | X is -1. */
11255 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11256 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11258 t1 = fold_convert_loc (loc, type, integer_zero_node);
11259 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11260 return omit_one_operand_loc (loc, type, t1, arg1);
11263 /* X | ~X is -1. */
11264 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11265 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11267 t1 = fold_convert_loc (loc, type, integer_zero_node);
11268 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11269 return omit_one_operand_loc (loc, type, t1, arg0);
11272 /* Canonicalize (X & C1) | C2. */
11273 if (TREE_CODE (arg0) == BIT_AND_EXPR
11274 && TREE_CODE (arg1) == INTEGER_CST
11275 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11277 unsigned HOST_WIDE_INT hi1, lo1, hi2, lo2, hi3, lo3, mlo, mhi;
11278 int width = TYPE_PRECISION (type), w;
11279 hi1 = TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1));
11280 lo1 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
11281 hi2 = TREE_INT_CST_HIGH (arg1);
11282 lo2 = TREE_INT_CST_LOW (arg1);
11284 /* If (C1&C2) == C1, then (X&C1)|C2 becomes (X,C2). */
11285 if ((hi1 & hi2) == hi1 && (lo1 & lo2) == lo1)
11286 return omit_one_operand_loc (loc, type, arg1,
11287 TREE_OPERAND (arg0, 0));
11289 if (width > HOST_BITS_PER_WIDE_INT)
11291 mhi = (unsigned HOST_WIDE_INT) -1
11292 >> (2 * HOST_BITS_PER_WIDE_INT - width);
11298 mlo = (unsigned HOST_WIDE_INT) -1
11299 >> (HOST_BITS_PER_WIDE_INT - width);
11302 /* If (C1|C2) == ~0 then (X&C1)|C2 becomes X|C2. */
11303 if ((~(hi1 | hi2) & mhi) == 0 && (~(lo1 | lo2) & mlo) == 0)
11304 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11305 TREE_OPERAND (arg0, 0), arg1);
11307 /* Minimize the number of bits set in C1, i.e. C1 := C1 & ~C2,
11308 unless (C1 & ~C2) | (C2 & C3) for some C3 is a mask of some
11309 mode which allows further optimizations. */
11316 for (w = BITS_PER_UNIT;
11317 w <= width && w <= HOST_BITS_PER_WIDE_INT;
11320 unsigned HOST_WIDE_INT mask
11321 = (unsigned HOST_WIDE_INT) -1 >> (HOST_BITS_PER_WIDE_INT - w);
11322 if (((lo1 | lo2) & mask) == mask
11323 && (lo1 & ~mask) == 0 && hi1 == 0)
11330 if (hi3 != hi1 || lo3 != lo1)
11331 return fold_build2_loc (loc, BIT_IOR_EXPR, type,
11332 fold_build2_loc (loc, BIT_AND_EXPR, type,
11333 TREE_OPERAND (arg0, 0),
11334 build_int_cst_wide (type,
11339 /* (X & Y) | Y is (X, Y). */
11340 if (TREE_CODE (arg0) == BIT_AND_EXPR
11341 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11342 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11343 /* (X & Y) | X is (Y, X). */
11344 if (TREE_CODE (arg0) == BIT_AND_EXPR
11345 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11346 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11347 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11348 /* X | (X & Y) is (Y, X). */
11349 if (TREE_CODE (arg1) == BIT_AND_EXPR
11350 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11351 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11352 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11353 /* X | (Y & X) is (Y, X). */
11354 if (TREE_CODE (arg1) == BIT_AND_EXPR
11355 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11356 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11357 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11359 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11360 if (t1 != NULL_TREE)
11363 /* Convert (or (not arg0) (not arg1)) to (not (and (arg0) (arg1))).
11365 This results in more efficient code for machines without a NAND
11366 instruction. Combine will canonicalize to the first form
11367 which will allow use of NAND instructions provided by the
11368 backend if they exist. */
11369 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11370 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11373 fold_build1_loc (loc, BIT_NOT_EXPR, type,
11374 build2 (BIT_AND_EXPR, type,
11375 fold_convert_loc (loc, type,
11376 TREE_OPERAND (arg0, 0)),
11377 fold_convert_loc (loc, type,
11378 TREE_OPERAND (arg1, 0))));
11381 /* See if this can be simplified into a rotate first. If that
11382 is unsuccessful continue in the association code. */
11386 if (integer_zerop (arg1))
11387 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11388 if (integer_all_onesp (arg1))
11389 return fold_build1_loc (loc, BIT_NOT_EXPR, type, op0);
11390 if (operand_equal_p (arg0, arg1, 0))
11391 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11393 /* ~X ^ X is -1. */
11394 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11395 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11397 t1 = fold_convert_loc (loc, type, integer_zero_node);
11398 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11399 return omit_one_operand_loc (loc, type, t1, arg1);
11402 /* X ^ ~X is -1. */
11403 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11404 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11406 t1 = fold_convert_loc (loc, type, integer_zero_node);
11407 t1 = fold_unary_loc (loc, BIT_NOT_EXPR, type, t1);
11408 return omit_one_operand_loc (loc, type, t1, arg0);
11411 /* If we are XORing two BIT_AND_EXPR's, both of which are and'ing
11412 with a constant, and the two constants have no bits in common,
11413 we should treat this as a BIT_IOR_EXPR since this may produce more
11414 simplifications. */
11415 if (TREE_CODE (arg0) == BIT_AND_EXPR
11416 && TREE_CODE (arg1) == BIT_AND_EXPR
11417 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
11418 && TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST
11419 && integer_zerop (const_binop (BIT_AND_EXPR,
11420 TREE_OPERAND (arg0, 1),
11421 TREE_OPERAND (arg1, 1), 0)))
11423 code = BIT_IOR_EXPR;
11427 /* (X | Y) ^ X -> Y & ~ X*/
11428 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11429 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11431 tree t2 = TREE_OPERAND (arg0, 1);
11432 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11434 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11435 fold_convert_loc (loc, type, t2),
11436 fold_convert_loc (loc, type, t1));
11440 /* (Y | X) ^ X -> Y & ~ X*/
11441 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11442 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11444 tree t2 = TREE_OPERAND (arg0, 0);
11445 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1),
11447 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11448 fold_convert_loc (loc, type, t2),
11449 fold_convert_loc (loc, type, t1));
11453 /* X ^ (X | Y) -> Y & ~ X*/
11454 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11455 && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
11457 tree t2 = TREE_OPERAND (arg1, 1);
11458 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11460 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11461 fold_convert_loc (loc, type, t2),
11462 fold_convert_loc (loc, type, t1));
11466 /* X ^ (Y | X) -> Y & ~ X*/
11467 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11468 && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
11470 tree t2 = TREE_OPERAND (arg1, 0);
11471 t1 = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg0),
11473 t1 = fold_build2_loc (loc, BIT_AND_EXPR, type,
11474 fold_convert_loc (loc, type, t2),
11475 fold_convert_loc (loc, type, t1));
11479 /* Convert ~X ^ ~Y to X ^ Y. */
11480 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11481 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11482 return fold_build2_loc (loc, code, type,
11483 fold_convert_loc (loc, type,
11484 TREE_OPERAND (arg0, 0)),
11485 fold_convert_loc (loc, type,
11486 TREE_OPERAND (arg1, 0)));
11488 /* Convert ~X ^ C to X ^ ~C. */
11489 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11490 && TREE_CODE (arg1) == INTEGER_CST)
11491 return fold_build2_loc (loc, code, type,
11492 fold_convert_loc (loc, type,
11493 TREE_OPERAND (arg0, 0)),
11494 fold_build1_loc (loc, BIT_NOT_EXPR, type, arg1));
11496 /* Fold (X & 1) ^ 1 as (X & 1) == 0. */
11497 if (TREE_CODE (arg0) == BIT_AND_EXPR
11498 && integer_onep (TREE_OPERAND (arg0, 1))
11499 && integer_onep (arg1))
11500 return fold_build2_loc (loc, EQ_EXPR, type, arg0,
11501 build_int_cst (TREE_TYPE (arg0), 0));
11503 /* Fold (X & Y) ^ Y as ~X & Y. */
11504 if (TREE_CODE (arg0) == BIT_AND_EXPR
11505 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11507 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11508 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11509 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11510 fold_convert_loc (loc, type, arg1));
11512 /* Fold (X & Y) ^ X as ~Y & X. */
11513 if (TREE_CODE (arg0) == BIT_AND_EXPR
11514 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11515 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11517 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11518 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11519 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11520 fold_convert_loc (loc, type, arg1));
11522 /* Fold X ^ (X & Y) as X & ~Y. */
11523 if (TREE_CODE (arg1) == BIT_AND_EXPR
11524 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11526 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11527 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11528 fold_convert_loc (loc, type, arg0),
11529 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11531 /* Fold X ^ (Y & X) as ~Y & X. */
11532 if (TREE_CODE (arg1) == BIT_AND_EXPR
11533 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11534 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11536 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11537 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11538 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11539 fold_convert_loc (loc, type, arg0));
11542 /* See if this can be simplified into a rotate first. If that
11543 is unsuccessful continue in the association code. */
11547 if (integer_all_onesp (arg1))
11548 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11549 if (integer_zerop (arg1))
11550 return omit_one_operand_loc (loc, type, arg1, arg0);
11551 if (operand_equal_p (arg0, arg1, 0))
11552 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11554 /* ~X & X is always zero. */
11555 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11556 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
11557 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
11559 /* X & ~X is always zero. */
11560 if (TREE_CODE (arg1) == BIT_NOT_EXPR
11561 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11562 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
11564 /* Canonicalize (X | C1) & C2 as (X & C2) | (C1 & C2). */
11565 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11566 && TREE_CODE (arg1) == INTEGER_CST
11567 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
11569 tree tmp1 = fold_convert_loc (loc, type, arg1);
11570 tree tmp2 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11571 tree tmp3 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11572 tmp2 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp2, tmp1);
11573 tmp3 = fold_build2_loc (loc, BIT_AND_EXPR, type, tmp3, tmp1);
11575 fold_convert_loc (loc, type,
11576 fold_build2_loc (loc, BIT_IOR_EXPR,
11577 type, tmp2, tmp3));
11580 /* (X | Y) & Y is (X, Y). */
11581 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11582 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11583 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 0));
11584 /* (X | Y) & X is (Y, X). */
11585 if (TREE_CODE (arg0) == BIT_IOR_EXPR
11586 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11587 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11588 return omit_one_operand_loc (loc, type, arg1, TREE_OPERAND (arg0, 1));
11589 /* X & (X | Y) is (Y, X). */
11590 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11591 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0)
11592 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 1)))
11593 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 1));
11594 /* X & (Y | X) is (Y, X). */
11595 if (TREE_CODE (arg1) == BIT_IOR_EXPR
11596 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11597 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11598 return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
11600 /* Fold (X ^ 1) & 1 as (X & 1) == 0. */
11601 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11602 && integer_onep (TREE_OPERAND (arg0, 1))
11603 && integer_onep (arg1))
11605 tem = TREE_OPERAND (arg0, 0);
11606 return fold_build2_loc (loc, EQ_EXPR, type,
11607 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11608 build_int_cst (TREE_TYPE (tem), 1)),
11609 build_int_cst (TREE_TYPE (tem), 0));
11611 /* Fold ~X & 1 as (X & 1) == 0. */
11612 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11613 && integer_onep (arg1))
11615 tem = TREE_OPERAND (arg0, 0);
11616 return fold_build2_loc (loc, EQ_EXPR, type,
11617 fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem), tem,
11618 build_int_cst (TREE_TYPE (tem), 1)),
11619 build_int_cst (TREE_TYPE (tem), 0));
11622 /* Fold (X ^ Y) & Y as ~X & Y. */
11623 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11624 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
11626 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11627 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11628 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11629 fold_convert_loc (loc, type, arg1));
11631 /* Fold (X ^ Y) & X as ~Y & X. */
11632 if (TREE_CODE (arg0) == BIT_XOR_EXPR
11633 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
11634 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
11636 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
11637 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11638 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11639 fold_convert_loc (loc, type, arg1));
11641 /* Fold X & (X ^ Y) as X & ~Y. */
11642 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11643 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
11645 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
11646 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11647 fold_convert_loc (loc, type, arg0),
11648 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem));
11650 /* Fold X & (Y ^ X) as ~Y & X. */
11651 if (TREE_CODE (arg1) == BIT_XOR_EXPR
11652 && operand_equal_p (arg0, TREE_OPERAND (arg1, 1), 0)
11653 && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
11655 tem = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
11656 return fold_build2_loc (loc, BIT_AND_EXPR, type,
11657 fold_build1_loc (loc, BIT_NOT_EXPR, type, tem),
11658 fold_convert_loc (loc, type, arg0));
11661 t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
11662 if (t1 != NULL_TREE)
11664 /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
11665 if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
11666 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
11669 = TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)));
11671 if (prec < BITS_PER_WORD && prec < HOST_BITS_PER_WIDE_INT
11672 && (~TREE_INT_CST_LOW (arg1)
11673 & (((HOST_WIDE_INT) 1 << prec) - 1)) == 0)
11675 fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
11678 /* Convert (and (not arg0) (not arg1)) to (not (or (arg0) (arg1))).
11680 This results in more efficient code for machines without a NOR
11681 instruction. Combine will canonicalize to the first form
11682 which will allow use of NOR instructions provided by the
11683 backend if they exist. */
11684 if (TREE_CODE (arg0) == BIT_NOT_EXPR
11685 && TREE_CODE (arg1) == BIT_NOT_EXPR)
11687 return fold_build1_loc (loc, BIT_NOT_EXPR, type,
11688 build2 (BIT_IOR_EXPR, type,
11689 fold_convert_loc (loc, type,
11690 TREE_OPERAND (arg0, 0)),
11691 fold_convert_loc (loc, type,
11692 TREE_OPERAND (arg1, 0))));
11695 /* If arg0 is derived from the address of an object or function, we may
11696 be able to fold this expression using the object or function's
11698 if (POINTER_TYPE_P (TREE_TYPE (arg0)) && host_integerp (arg1, 1))
11700 unsigned HOST_WIDE_INT modulus, residue;
11701 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1);
11703 modulus = get_pointer_modulus_and_residue (arg0, &residue,
11704 integer_onep (arg1));
11706 /* This works because modulus is a power of 2. If this weren't the
11707 case, we'd have to replace it by its greatest power-of-2
11708 divisor: modulus & -modulus. */
11710 return build_int_cst (type, residue & low);
11713 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
11714 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
11715 if the new mask might be further optimized. */
11716 if ((TREE_CODE (arg0) == LSHIFT_EXPR
11717 || TREE_CODE (arg0) == RSHIFT_EXPR)
11718 && host_integerp (TREE_OPERAND (arg0, 1), 1)
11719 && host_integerp (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)))
11720 && tree_low_cst (TREE_OPERAND (arg0, 1), 1)
11721 < TYPE_PRECISION (TREE_TYPE (arg0))
11722 && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT
11723 && tree_low_cst (TREE_OPERAND (arg0, 1), 1) > 0)
11725 unsigned int shiftc = tree_low_cst (TREE_OPERAND (arg0, 1), 1);
11726 unsigned HOST_WIDE_INT mask
11727 = tree_low_cst (arg1, TYPE_UNSIGNED (TREE_TYPE (arg1)));
11728 unsigned HOST_WIDE_INT newmask, zerobits = 0;
11729 tree shift_type = TREE_TYPE (arg0);
11731 if (TREE_CODE (arg0) == LSHIFT_EXPR)
11732 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
11733 else if (TREE_CODE (arg0) == RSHIFT_EXPR
11734 && TYPE_PRECISION (TREE_TYPE (arg0))
11735 == GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (arg0))))
11737 unsigned int prec = TYPE_PRECISION (TREE_TYPE (arg0));
11738 tree arg00 = TREE_OPERAND (arg0, 0);
11739 /* See if more bits can be proven as zero because of
11741 if (TREE_CODE (arg00) == NOP_EXPR
11742 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0))))
11744 tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0));
11745 if (TYPE_PRECISION (inner_type)
11746 == GET_MODE_BITSIZE (TYPE_MODE (inner_type))
11747 && TYPE_PRECISION (inner_type) < prec)
11749 prec = TYPE_PRECISION (inner_type);
11750 /* See if we can shorten the right shift. */
11752 shift_type = inner_type;
11755 zerobits = ~(unsigned HOST_WIDE_INT) 0;
11756 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
11757 zerobits <<= prec - shiftc;
11758 /* For arithmetic shift if sign bit could be set, zerobits
11759 can contain actually sign bits, so no transformation is
11760 possible, unless MASK masks them all away. In that
11761 case the shift needs to be converted into logical shift. */
11762 if (!TYPE_UNSIGNED (TREE_TYPE (arg0))
11763 && prec == TYPE_PRECISION (TREE_TYPE (arg0)))
11765 if ((mask & zerobits) == 0)
11766 shift_type = unsigned_type_for (TREE_TYPE (arg0));
11772 /* ((X << 16) & 0xff00) is (X, 0). */
11773 if ((mask & zerobits) == mask)
11774 return omit_one_operand_loc (loc, type,
11775 build_int_cst (type, 0), arg0);
11777 newmask = mask | zerobits;
11778 if (newmask != mask && (newmask & (newmask + 1)) == 0)
11782 /* Only do the transformation if NEWMASK is some integer
11784 for (prec = BITS_PER_UNIT;
11785 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
11786 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
11788 if (prec < HOST_BITS_PER_WIDE_INT
11789 || newmask == ~(unsigned HOST_WIDE_INT) 0)
11793 if (shift_type != TREE_TYPE (arg0))
11795 tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type,
11796 fold_convert_loc (loc, shift_type,
11797 TREE_OPERAND (arg0, 0)),
11798 TREE_OPERAND (arg0, 1));
11799 tem = fold_convert_loc (loc, type, tem);
11803 newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask);
11804 if (!tree_int_cst_equal (newmaskt, arg1))
11805 return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt);
11813 /* Don't touch a floating-point divide by zero unless the mode
11814 of the constant can represent infinity. */
11815 if (TREE_CODE (arg1) == REAL_CST
11816 && !MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (arg1)))
11817 && real_zerop (arg1))
11820 /* Optimize A / A to 1.0 if we don't care about
11821 NaNs or Infinities. Skip the transformation
11822 for non-real operands. */
11823 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (arg0))
11824 && ! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
11825 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg0)))
11826 && operand_equal_p (arg0, arg1, 0))
11828 tree r = build_real (TREE_TYPE (arg0), dconst1);
11830 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11833 /* The complex version of the above A / A optimization. */
11834 if (COMPLEX_FLOAT_TYPE_P (TREE_TYPE (arg0))
11835 && operand_equal_p (arg0, arg1, 0))
11837 tree elem_type = TREE_TYPE (TREE_TYPE (arg0));
11838 if (! HONOR_NANS (TYPE_MODE (elem_type))
11839 && ! HONOR_INFINITIES (TYPE_MODE (elem_type)))
11841 tree r = build_real (elem_type, dconst1);
11842 /* omit_two_operands will call fold_convert for us. */
11843 return omit_two_operands_loc (loc, type, r, arg0, arg1);
11847 /* (-A) / (-B) -> A / B */
11848 if (TREE_CODE (arg0) == NEGATE_EXPR && negate_expr_p (arg1))
11849 return fold_build2_loc (loc, RDIV_EXPR, type,
11850 TREE_OPERAND (arg0, 0),
11851 negate_expr (arg1));
11852 if (TREE_CODE (arg1) == NEGATE_EXPR && negate_expr_p (arg0))
11853 return fold_build2_loc (loc, RDIV_EXPR, type,
11854 negate_expr (arg0),
11855 TREE_OPERAND (arg1, 0));
11857 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
11858 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11859 && real_onep (arg1))
11860 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
11862 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
11863 if (!HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0)))
11864 && real_minus_onep (arg1))
11865 return non_lvalue_loc (loc, fold_convert_loc (loc, type,
11866 negate_expr (arg0)));
11868 /* If ARG1 is a constant, we can convert this to a multiply by the
11869 reciprocal. This does not have the same rounding properties,
11870 so only do this if -freciprocal-math. We can actually
11871 always safely do it if ARG1 is a power of two, but it's hard to
11872 tell if it is or not in a portable manner. */
11873 if (TREE_CODE (arg1) == REAL_CST)
11875 if (flag_reciprocal_math
11876 && 0 != (tem = const_binop (code, build_real (type, dconst1),
11878 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tem);
11879 /* Find the reciprocal if optimizing and the result is exact. */
11883 r = TREE_REAL_CST (arg1);
11884 if (exact_real_inverse (TYPE_MODE(TREE_TYPE(arg0)), &r))
11886 tem = build_real (type, r);
11887 return fold_build2_loc (loc, MULT_EXPR, type,
11888 fold_convert_loc (loc, type, arg0), tem);
11892 /* Convert A/B/C to A/(B*C). */
11893 if (flag_reciprocal_math
11894 && TREE_CODE (arg0) == RDIV_EXPR)
11895 return fold_build2_loc (loc, RDIV_EXPR, type, TREE_OPERAND (arg0, 0),
11896 fold_build2_loc (loc, MULT_EXPR, type,
11897 TREE_OPERAND (arg0, 1), arg1));
11899 /* Convert A/(B/C) to (A/B)*C. */
11900 if (flag_reciprocal_math
11901 && TREE_CODE (arg1) == RDIV_EXPR)
11902 return fold_build2_loc (loc, MULT_EXPR, type,
11903 fold_build2_loc (loc, RDIV_EXPR, type, arg0,
11904 TREE_OPERAND (arg1, 0)),
11905 TREE_OPERAND (arg1, 1));
11907 /* Convert C1/(X*C2) into (C1/C2)/X. */
11908 if (flag_reciprocal_math
11909 && TREE_CODE (arg1) == MULT_EXPR
11910 && TREE_CODE (arg0) == REAL_CST
11911 && TREE_CODE (TREE_OPERAND (arg1, 1)) == REAL_CST)
11913 tree tem = const_binop (RDIV_EXPR, arg0,
11914 TREE_OPERAND (arg1, 1), 0);
11916 return fold_build2_loc (loc, RDIV_EXPR, type, tem,
11917 TREE_OPERAND (arg1, 0));
11920 if (flag_unsafe_math_optimizations)
11922 enum built_in_function fcode0 = builtin_mathfn_code (arg0);
11923 enum built_in_function fcode1 = builtin_mathfn_code (arg1);
11925 /* Optimize sin(x)/cos(x) as tan(x). */
11926 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_COS)
11927 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_COSF)
11928 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_COSL))
11929 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11930 CALL_EXPR_ARG (arg1, 0), 0))
11932 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11934 if (tanfn != NULL_TREE)
11935 return build_call_expr_loc (loc, tanfn, 1, CALL_EXPR_ARG (arg0, 0));
11938 /* Optimize cos(x)/sin(x) as 1.0/tan(x). */
11939 if (((fcode0 == BUILT_IN_COS && fcode1 == BUILT_IN_SIN)
11940 || (fcode0 == BUILT_IN_COSF && fcode1 == BUILT_IN_SINF)
11941 || (fcode0 == BUILT_IN_COSL && fcode1 == BUILT_IN_SINL))
11942 && operand_equal_p (CALL_EXPR_ARG (arg0, 0),
11943 CALL_EXPR_ARG (arg1, 0), 0))
11945 tree tanfn = mathfn_built_in (type, BUILT_IN_TAN);
11947 if (tanfn != NULL_TREE)
11949 tree tmp = build_call_expr_loc (loc, tanfn, 1,
11950 CALL_EXPR_ARG (arg0, 0));
11951 return fold_build2_loc (loc, RDIV_EXPR, type,
11952 build_real (type, dconst1), tmp);
11956 /* Optimize sin(x)/tan(x) as cos(x) if we don't care about
11957 NaNs or Infinities. */
11958 if (((fcode0 == BUILT_IN_SIN && fcode1 == BUILT_IN_TAN)
11959 || (fcode0 == BUILT_IN_SINF && fcode1 == BUILT_IN_TANF)
11960 || (fcode0 == BUILT_IN_SINL && fcode1 == BUILT_IN_TANL)))
11962 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11963 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11965 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11966 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11967 && operand_equal_p (arg00, arg01, 0))
11969 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11971 if (cosfn != NULL_TREE)
11972 return build_call_expr_loc (loc, cosfn, 1, arg00);
11976 /* Optimize tan(x)/sin(x) as 1.0/cos(x) if we don't care about
11977 NaNs or Infinities. */
11978 if (((fcode0 == BUILT_IN_TAN && fcode1 == BUILT_IN_SIN)
11979 || (fcode0 == BUILT_IN_TANF && fcode1 == BUILT_IN_SINF)
11980 || (fcode0 == BUILT_IN_TANL && fcode1 == BUILT_IN_SINL)))
11982 tree arg00 = CALL_EXPR_ARG (arg0, 0);
11983 tree arg01 = CALL_EXPR_ARG (arg1, 0);
11985 if (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg00)))
11986 && ! HONOR_INFINITIES (TYPE_MODE (TREE_TYPE (arg00)))
11987 && operand_equal_p (arg00, arg01, 0))
11989 tree cosfn = mathfn_built_in (type, BUILT_IN_COS);
11991 if (cosfn != NULL_TREE)
11993 tree tmp = build_call_expr_loc (loc, cosfn, 1, arg00);
11994 return fold_build2_loc (loc, RDIV_EXPR, type,
11995 build_real (type, dconst1),
12001 /* Optimize pow(x,c)/x as pow(x,c-1). */
12002 if (fcode0 == BUILT_IN_POW
12003 || fcode0 == BUILT_IN_POWF
12004 || fcode0 == BUILT_IN_POWL)
12006 tree arg00 = CALL_EXPR_ARG (arg0, 0);
12007 tree arg01 = CALL_EXPR_ARG (arg0, 1);
12008 if (TREE_CODE (arg01) == REAL_CST
12009 && !TREE_OVERFLOW (arg01)
12010 && operand_equal_p (arg1, arg00, 0))
12012 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg0), 0);
12016 c = TREE_REAL_CST (arg01);
12017 real_arithmetic (&c, MINUS_EXPR, &c, &dconst1);
12018 arg = build_real (type, c);
12019 return build_call_expr_loc (loc, powfn, 2, arg1, arg);
12023 /* Optimize a/root(b/c) into a*root(c/b). */
12024 if (BUILTIN_ROOT_P (fcode1))
12026 tree rootarg = CALL_EXPR_ARG (arg1, 0);
12028 if (TREE_CODE (rootarg) == RDIV_EXPR)
12030 tree rootfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12031 tree b = TREE_OPERAND (rootarg, 0);
12032 tree c = TREE_OPERAND (rootarg, 1);
12034 tree tmp = fold_build2_loc (loc, RDIV_EXPR, type, c, b);
12036 tmp = build_call_expr_loc (loc, rootfn, 1, tmp);
12037 return fold_build2_loc (loc, MULT_EXPR, type, arg0, tmp);
12041 /* Optimize x/expN(y) into x*expN(-y). */
12042 if (BUILTIN_EXPONENT_P (fcode1))
12044 tree expfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12045 tree arg = negate_expr (CALL_EXPR_ARG (arg1, 0));
12046 arg1 = build_call_expr_loc (loc,
12048 fold_convert_loc (loc, type, arg));
12049 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
12052 /* Optimize x/pow(y,z) into x*pow(y,-z). */
12053 if (fcode1 == BUILT_IN_POW
12054 || fcode1 == BUILT_IN_POWF
12055 || fcode1 == BUILT_IN_POWL)
12057 tree powfn = TREE_OPERAND (CALL_EXPR_FN (arg1), 0);
12058 tree arg10 = CALL_EXPR_ARG (arg1, 0);
12059 tree arg11 = CALL_EXPR_ARG (arg1, 1);
12060 tree neg11 = fold_convert_loc (loc, type,
12061 negate_expr (arg11));
12062 arg1 = build_call_expr_loc (loc, powfn, 2, arg10, neg11);
12063 return fold_build2_loc (loc, MULT_EXPR, type, arg0, arg1);
12068 case TRUNC_DIV_EXPR:
12069 case FLOOR_DIV_EXPR:
12070 /* Simplify A / (B << N) where A and B are positive and B is
12071 a power of 2, to A >> (N + log2(B)). */
12072 strict_overflow_p = false;
12073 if (TREE_CODE (arg1) == LSHIFT_EXPR
12074 && (TYPE_UNSIGNED (type)
12075 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
12077 tree sval = TREE_OPERAND (arg1, 0);
12078 if (integer_pow2p (sval) && tree_int_cst_sgn (sval) > 0)
12080 tree sh_cnt = TREE_OPERAND (arg1, 1);
12081 unsigned long pow2 = exact_log2 (TREE_INT_CST_LOW (sval));
12083 if (strict_overflow_p)
12084 fold_overflow_warning (("assuming signed overflow does not "
12085 "occur when simplifying A / (B << N)"),
12086 WARN_STRICT_OVERFLOW_MISC);
12088 sh_cnt = fold_build2_loc (loc, PLUS_EXPR, TREE_TYPE (sh_cnt),
12089 sh_cnt, build_int_cst (NULL_TREE, pow2));
12090 return fold_build2_loc (loc, RSHIFT_EXPR, type,
12091 fold_convert_loc (loc, type, arg0), sh_cnt);
12095 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
12096 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
12097 if (INTEGRAL_TYPE_P (type)
12098 && TYPE_UNSIGNED (type)
12099 && code == FLOOR_DIV_EXPR)
12100 return fold_build2_loc (loc, TRUNC_DIV_EXPR, type, op0, op1);
12104 case ROUND_DIV_EXPR:
12105 case CEIL_DIV_EXPR:
12106 case EXACT_DIV_EXPR:
12107 if (integer_onep (arg1))
12108 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12109 if (integer_zerop (arg1))
12111 /* X / -1 is -X. */
12112 if (!TYPE_UNSIGNED (type)
12113 && TREE_CODE (arg1) == INTEGER_CST
12114 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12115 && TREE_INT_CST_HIGH (arg1) == -1)
12116 return fold_convert_loc (loc, type, negate_expr (arg0));
12118 /* Convert -A / -B to A / B when the type is signed and overflow is
12120 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12121 && TREE_CODE (arg0) == NEGATE_EXPR
12122 && negate_expr_p (arg1))
12124 if (INTEGRAL_TYPE_P (type))
12125 fold_overflow_warning (("assuming signed overflow does not occur "
12126 "when distributing negation across "
12128 WARN_STRICT_OVERFLOW_MISC);
12129 return fold_build2_loc (loc, code, type,
12130 fold_convert_loc (loc, type,
12131 TREE_OPERAND (arg0, 0)),
12132 fold_convert_loc (loc, type,
12133 negate_expr (arg1)));
12135 if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
12136 && TREE_CODE (arg1) == NEGATE_EXPR
12137 && negate_expr_p (arg0))
12139 if (INTEGRAL_TYPE_P (type))
12140 fold_overflow_warning (("assuming signed overflow does not occur "
12141 "when distributing negation across "
12143 WARN_STRICT_OVERFLOW_MISC);
12144 return fold_build2_loc (loc, code, type,
12145 fold_convert_loc (loc, type,
12146 negate_expr (arg0)),
12147 fold_convert_loc (loc, type,
12148 TREE_OPERAND (arg1, 0)));
12151 /* If arg0 is a multiple of arg1, then rewrite to the fastest div
12152 operation, EXACT_DIV_EXPR.
12154 Note that only CEIL_DIV_EXPR and FLOOR_DIV_EXPR are rewritten now.
12155 At one time others generated faster code, it's not clear if they do
12156 after the last round to changes to the DIV code in expmed.c. */
12157 if ((code == CEIL_DIV_EXPR || code == FLOOR_DIV_EXPR)
12158 && multiple_of_p (type, arg0, arg1))
12159 return fold_build2_loc (loc, EXACT_DIV_EXPR, type, arg0, arg1);
12161 strict_overflow_p = false;
12162 if (TREE_CODE (arg1) == INTEGER_CST
12163 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12164 &strict_overflow_p)))
12166 if (strict_overflow_p)
12167 fold_overflow_warning (("assuming signed overflow does not occur "
12168 "when simplifying division"),
12169 WARN_STRICT_OVERFLOW_MISC);
12170 return fold_convert_loc (loc, type, tem);
12175 case CEIL_MOD_EXPR:
12176 case FLOOR_MOD_EXPR:
12177 case ROUND_MOD_EXPR:
12178 case TRUNC_MOD_EXPR:
12179 /* X % 1 is always zero, but be sure to preserve any side
12181 if (integer_onep (arg1))
12182 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12184 /* X % 0, return X % 0 unchanged so that we can get the
12185 proper warnings and errors. */
12186 if (integer_zerop (arg1))
12189 /* 0 % X is always zero, but be sure to preserve any side
12190 effects in X. Place this after checking for X == 0. */
12191 if (integer_zerop (arg0))
12192 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12194 /* X % -1 is zero. */
12195 if (!TYPE_UNSIGNED (type)
12196 && TREE_CODE (arg1) == INTEGER_CST
12197 && TREE_INT_CST_LOW (arg1) == (unsigned HOST_WIDE_INT) -1
12198 && TREE_INT_CST_HIGH (arg1) == -1)
12199 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12201 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
12202 i.e. "X % C" into "X & (C - 1)", if X and C are positive. */
12203 strict_overflow_p = false;
12204 if ((code == TRUNC_MOD_EXPR || code == FLOOR_MOD_EXPR)
12205 && (TYPE_UNSIGNED (type)
12206 || tree_expr_nonnegative_warnv_p (op0, &strict_overflow_p)))
12209 /* Also optimize A % (C << N) where C is a power of 2,
12210 to A & ((C << N) - 1). */
12211 if (TREE_CODE (arg1) == LSHIFT_EXPR)
12212 c = TREE_OPERAND (arg1, 0);
12214 if (integer_pow2p (c) && tree_int_cst_sgn (c) > 0)
12216 tree mask = fold_build2_loc (loc, MINUS_EXPR, TREE_TYPE (arg1), arg1,
12217 build_int_cst (TREE_TYPE (arg1), 1));
12218 if (strict_overflow_p)
12219 fold_overflow_warning (("assuming signed overflow does not "
12220 "occur when simplifying "
12221 "X % (power of two)"),
12222 WARN_STRICT_OVERFLOW_MISC);
12223 return fold_build2_loc (loc, BIT_AND_EXPR, type,
12224 fold_convert_loc (loc, type, arg0),
12225 fold_convert_loc (loc, type, mask));
12229 /* X % -C is the same as X % C. */
12230 if (code == TRUNC_MOD_EXPR
12231 && !TYPE_UNSIGNED (type)
12232 && TREE_CODE (arg1) == INTEGER_CST
12233 && !TREE_OVERFLOW (arg1)
12234 && TREE_INT_CST_HIGH (arg1) < 0
12235 && !TYPE_OVERFLOW_TRAPS (type)
12236 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
12237 && !sign_bit_p (arg1, arg1))
12238 return fold_build2_loc (loc, code, type,
12239 fold_convert_loc (loc, type, arg0),
12240 fold_convert_loc (loc, type,
12241 negate_expr (arg1)));
12243 /* X % -Y is the same as X % Y. */
12244 if (code == TRUNC_MOD_EXPR
12245 && !TYPE_UNSIGNED (type)
12246 && TREE_CODE (arg1) == NEGATE_EXPR
12247 && !TYPE_OVERFLOW_TRAPS (type))
12248 return fold_build2_loc (loc, code, type, fold_convert_loc (loc, type, arg0),
12249 fold_convert_loc (loc, type,
12250 TREE_OPERAND (arg1, 0)));
12252 if (TREE_CODE (arg1) == INTEGER_CST
12253 && 0 != (tem = extract_muldiv (op0, arg1, code, NULL_TREE,
12254 &strict_overflow_p)))
12256 if (strict_overflow_p)
12257 fold_overflow_warning (("assuming signed overflow does not occur "
12258 "when simplifying modulus"),
12259 WARN_STRICT_OVERFLOW_MISC);
12260 return fold_convert_loc (loc, type, tem);
12267 if (integer_all_onesp (arg0))
12268 return omit_one_operand_loc (loc, type, arg0, arg1);
12272 /* Optimize -1 >> x for arithmetic right shifts. */
12273 if (integer_all_onesp (arg0) && !TYPE_UNSIGNED (type)
12274 && tree_expr_nonnegative_p (arg1))
12275 return omit_one_operand_loc (loc, type, arg0, arg1);
12276 /* ... fall through ... */
12280 if (integer_zerop (arg1))
12281 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12282 if (integer_zerop (arg0))
12283 return omit_one_operand_loc (loc, type, arg0, arg1);
12285 /* Since negative shift count is not well-defined,
12286 don't try to compute it in the compiler. */
12287 if (TREE_CODE (arg1) == INTEGER_CST && tree_int_cst_sgn (arg1) < 0)
12290 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
12291 if (TREE_CODE (op0) == code && host_integerp (arg1, false)
12292 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12293 && host_integerp (TREE_OPERAND (arg0, 1), false)
12294 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12296 HOST_WIDE_INT low = (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1))
12297 + TREE_INT_CST_LOW (arg1));
12299 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
12300 being well defined. */
12301 if (low >= TYPE_PRECISION (type))
12303 if (code == LROTATE_EXPR || code == RROTATE_EXPR)
12304 low = low % TYPE_PRECISION (type);
12305 else if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
12306 return omit_one_operand_loc (loc, type, build_int_cst (type, 0),
12307 TREE_OPERAND (arg0, 0));
12309 low = TYPE_PRECISION (type) - 1;
12312 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12313 build_int_cst (type, low));
12316 /* Transform (x >> c) << c into x & (-1<<c), or transform (x << c) >> c
12317 into x & ((unsigned)-1 >> c) for unsigned types. */
12318 if (((code == LSHIFT_EXPR && TREE_CODE (arg0) == RSHIFT_EXPR)
12319 || (TYPE_UNSIGNED (type)
12320 && code == RSHIFT_EXPR && TREE_CODE (arg0) == LSHIFT_EXPR))
12321 && host_integerp (arg1, false)
12322 && TREE_INT_CST_LOW (arg1) < TYPE_PRECISION (type)
12323 && host_integerp (TREE_OPERAND (arg0, 1), false)
12324 && TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) < TYPE_PRECISION (type))
12326 HOST_WIDE_INT low0 = TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1));
12327 HOST_WIDE_INT low1 = TREE_INT_CST_LOW (arg1);
12333 arg00 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
12335 lshift = build_int_cst (type, -1);
12336 lshift = int_const_binop (code, lshift, arg1, 0);
12338 return fold_build2_loc (loc, BIT_AND_EXPR, type, arg00, lshift);
12342 /* Rewrite an LROTATE_EXPR by a constant into an
12343 RROTATE_EXPR by a new constant. */
12344 if (code == LROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST)
12346 tree tem = build_int_cst (TREE_TYPE (arg1),
12347 TYPE_PRECISION (type));
12348 tem = const_binop (MINUS_EXPR, tem, arg1, 0);
12349 return fold_build2_loc (loc, RROTATE_EXPR, type, op0, tem);
12352 /* If we have a rotate of a bit operation with the rotate count and
12353 the second operand of the bit operation both constant,
12354 permute the two operations. */
12355 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12356 && (TREE_CODE (arg0) == BIT_AND_EXPR
12357 || TREE_CODE (arg0) == BIT_IOR_EXPR
12358 || TREE_CODE (arg0) == BIT_XOR_EXPR)
12359 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12360 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12361 fold_build2_loc (loc, code, type,
12362 TREE_OPERAND (arg0, 0), arg1),
12363 fold_build2_loc (loc, code, type,
12364 TREE_OPERAND (arg0, 1), arg1));
12366 /* Two consecutive rotates adding up to the precision of the
12367 type can be ignored. */
12368 if (code == RROTATE_EXPR && TREE_CODE (arg1) == INTEGER_CST
12369 && TREE_CODE (arg0) == RROTATE_EXPR
12370 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12371 && TREE_INT_CST_HIGH (arg1) == 0
12372 && TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0
12373 && ((TREE_INT_CST_LOW (arg1)
12374 + TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)))
12375 == (unsigned int) TYPE_PRECISION (type)))
12376 return TREE_OPERAND (arg0, 0);
12378 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
12379 (X & C2) >> C1 into (X >> C1) & (C2 >> C1)
12380 if the latter can be further optimized. */
12381 if ((code == LSHIFT_EXPR || code == RSHIFT_EXPR)
12382 && TREE_CODE (arg0) == BIT_AND_EXPR
12383 && TREE_CODE (arg1) == INTEGER_CST
12384 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12386 tree mask = fold_build2_loc (loc, code, type,
12387 fold_convert_loc (loc, type,
12388 TREE_OPERAND (arg0, 1)),
12390 tree shift = fold_build2_loc (loc, code, type,
12391 fold_convert_loc (loc, type,
12392 TREE_OPERAND (arg0, 0)),
12394 tem = fold_binary_loc (loc, BIT_AND_EXPR, type, shift, mask);
12402 if (operand_equal_p (arg0, arg1, 0))
12403 return omit_one_operand_loc (loc, type, arg0, arg1);
12404 if (INTEGRAL_TYPE_P (type)
12405 && operand_equal_p (arg1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
12406 return omit_one_operand_loc (loc, type, arg1, arg0);
12407 tem = fold_minmax (loc, MIN_EXPR, type, arg0, arg1);
12413 if (operand_equal_p (arg0, arg1, 0))
12414 return omit_one_operand_loc (loc, type, arg0, arg1);
12415 if (INTEGRAL_TYPE_P (type)
12416 && TYPE_MAX_VALUE (type)
12417 && operand_equal_p (arg1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
12418 return omit_one_operand_loc (loc, type, arg1, arg0);
12419 tem = fold_minmax (loc, MAX_EXPR, type, arg0, arg1);
12424 case TRUTH_ANDIF_EXPR:
12425 /* Note that the operands of this must be ints
12426 and their values must be 0 or 1.
12427 ("true" is a fixed value perhaps depending on the language.) */
12428 /* If first arg is constant zero, return it. */
12429 if (integer_zerop (arg0))
12430 return fold_convert_loc (loc, type, arg0);
12431 case TRUTH_AND_EXPR:
12432 /* If either arg is constant true, drop it. */
12433 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12434 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12435 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1)
12436 /* Preserve sequence points. */
12437 && (code != TRUTH_ANDIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12438 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12439 /* If second arg is constant zero, result is zero, but first arg
12440 must be evaluated. */
12441 if (integer_zerop (arg1))
12442 return omit_one_operand_loc (loc, type, arg1, arg0);
12443 /* Likewise for first arg, but note that only the TRUTH_AND_EXPR
12444 case will be handled here. */
12445 if (integer_zerop (arg0))
12446 return omit_one_operand_loc (loc, type, arg0, arg1);
12448 /* !X && X is always false. */
12449 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12450 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12451 return omit_one_operand_loc (loc, type, integer_zero_node, arg1);
12452 /* X && !X is always false. */
12453 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12454 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12455 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12457 /* A < X && A + 1 > Y ==> A < X && A >= Y. Normally A + 1 > Y
12458 means A >= Y && A != MAX, but in this case we know that
12461 if (!TREE_SIDE_EFFECTS (arg0)
12462 && !TREE_SIDE_EFFECTS (arg1))
12464 tem = fold_to_nonsharp_ineq_using_bound (loc, arg0, arg1);
12465 if (tem && !operand_equal_p (tem, arg0, 0))
12466 return fold_build2_loc (loc, code, type, tem, arg1);
12468 tem = fold_to_nonsharp_ineq_using_bound (loc, arg1, arg0);
12469 if (tem && !operand_equal_p (tem, arg1, 0))
12470 return fold_build2_loc (loc, code, type, arg0, tem);
12474 /* We only do these simplifications if we are optimizing. */
12478 /* Check for things like (A || B) && (A || C). We can convert this
12479 to A || (B && C). Note that either operator can be any of the four
12480 truth and/or operations and the transformation will still be
12481 valid. Also note that we only care about order for the
12482 ANDIF and ORIF operators. If B contains side effects, this
12483 might change the truth-value of A. */
12484 if (TREE_CODE (arg0) == TREE_CODE (arg1)
12485 && (TREE_CODE (arg0) == TRUTH_ANDIF_EXPR
12486 || TREE_CODE (arg0) == TRUTH_ORIF_EXPR
12487 || TREE_CODE (arg0) == TRUTH_AND_EXPR
12488 || TREE_CODE (arg0) == TRUTH_OR_EXPR)
12489 && ! TREE_SIDE_EFFECTS (TREE_OPERAND (arg0, 1)))
12491 tree a00 = TREE_OPERAND (arg0, 0);
12492 tree a01 = TREE_OPERAND (arg0, 1);
12493 tree a10 = TREE_OPERAND (arg1, 0);
12494 tree a11 = TREE_OPERAND (arg1, 1);
12495 int commutative = ((TREE_CODE (arg0) == TRUTH_OR_EXPR
12496 || TREE_CODE (arg0) == TRUTH_AND_EXPR)
12497 && (code == TRUTH_AND_EXPR
12498 || code == TRUTH_OR_EXPR));
12500 if (operand_equal_p (a00, a10, 0))
12501 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12502 fold_build2_loc (loc, code, type, a01, a11));
12503 else if (commutative && operand_equal_p (a00, a11, 0))
12504 return fold_build2_loc (loc, TREE_CODE (arg0), type, a00,
12505 fold_build2_loc (loc, code, type, a01, a10));
12506 else if (commutative && operand_equal_p (a01, a10, 0))
12507 return fold_build2_loc (loc, TREE_CODE (arg0), type, a01,
12508 fold_build2_loc (loc, code, type, a00, a11));
12510 /* This case if tricky because we must either have commutative
12511 operators or else A10 must not have side-effects. */
12513 else if ((commutative || ! TREE_SIDE_EFFECTS (a10))
12514 && operand_equal_p (a01, a11, 0))
12515 return fold_build2_loc (loc, TREE_CODE (arg0), type,
12516 fold_build2_loc (loc, code, type, a00, a10),
12520 /* See if we can build a range comparison. */
12521 if (0 != (tem = fold_range_test (loc, code, type, op0, op1)))
12524 /* Check for the possibility of merging component references. If our
12525 lhs is another similar operation, try to merge its rhs with our
12526 rhs. Then try to merge our lhs and rhs. */
12527 if (TREE_CODE (arg0) == code
12528 && 0 != (tem = fold_truthop (loc, code, type,
12529 TREE_OPERAND (arg0, 1), arg1)))
12530 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12532 if ((tem = fold_truthop (loc, code, type, arg0, arg1)) != 0)
12537 case TRUTH_ORIF_EXPR:
12538 /* Note that the operands of this must be ints
12539 and their values must be 0 or true.
12540 ("true" is a fixed value perhaps depending on the language.) */
12541 /* If first arg is constant true, return it. */
12542 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12543 return fold_convert_loc (loc, type, arg0);
12544 case TRUTH_OR_EXPR:
12545 /* If either arg is constant zero, drop it. */
12546 if (TREE_CODE (arg0) == INTEGER_CST && integer_zerop (arg0))
12547 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg1));
12548 if (TREE_CODE (arg1) == INTEGER_CST && integer_zerop (arg1)
12549 /* Preserve sequence points. */
12550 && (code != TRUTH_ORIF_EXPR || ! TREE_SIDE_EFFECTS (arg0)))
12551 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12552 /* If second arg is constant true, result is true, but we must
12553 evaluate first arg. */
12554 if (TREE_CODE (arg1) == INTEGER_CST && ! integer_zerop (arg1))
12555 return omit_one_operand_loc (loc, type, arg1, arg0);
12556 /* Likewise for first arg, but note this only occurs here for
12558 if (TREE_CODE (arg0) == INTEGER_CST && ! integer_zerop (arg0))
12559 return omit_one_operand_loc (loc, type, arg0, arg1);
12561 /* !X || X is always true. */
12562 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12563 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12564 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12565 /* X || !X is always true. */
12566 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12567 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12568 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12572 case TRUTH_XOR_EXPR:
12573 /* If the second arg is constant zero, drop it. */
12574 if (integer_zerop (arg1))
12575 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12576 /* If the second arg is constant true, this is a logical inversion. */
12577 if (integer_onep (arg1))
12579 /* Only call invert_truthvalue if operand is a truth value. */
12580 if (TREE_CODE (TREE_TYPE (arg0)) != BOOLEAN_TYPE)
12581 tem = fold_build1_loc (loc, TRUTH_NOT_EXPR, TREE_TYPE (arg0), arg0);
12583 tem = invert_truthvalue_loc (loc, arg0);
12584 return non_lvalue_loc (loc, fold_convert_loc (loc, type, tem));
12586 /* Identical arguments cancel to zero. */
12587 if (operand_equal_p (arg0, arg1, 0))
12588 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
12590 /* !X ^ X is always true. */
12591 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
12592 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
12593 return omit_one_operand_loc (loc, type, integer_one_node, arg1);
12595 /* X ^ !X is always true. */
12596 if (TREE_CODE (arg1) == TRUTH_NOT_EXPR
12597 && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
12598 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
12604 tem = fold_comparison (loc, code, type, op0, op1);
12605 if (tem != NULL_TREE)
12608 /* bool_var != 0 becomes bool_var. */
12609 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12610 && code == NE_EXPR)
12611 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12613 /* bool_var == 1 becomes bool_var. */
12614 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12615 && code == EQ_EXPR)
12616 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12618 /* bool_var != 1 becomes !bool_var. */
12619 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_onep (arg1)
12620 && code == NE_EXPR)
12621 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12622 fold_convert_loc (loc, type, arg0));
12624 /* bool_var == 0 becomes !bool_var. */
12625 if (TREE_CODE (TREE_TYPE (arg0)) == BOOLEAN_TYPE && integer_zerop (arg1)
12626 && code == EQ_EXPR)
12627 return fold_build1_loc (loc, TRUTH_NOT_EXPR, type,
12628 fold_convert_loc (loc, type, arg0));
12630 /* !exp != 0 becomes !exp */
12631 if (TREE_CODE (arg0) == TRUTH_NOT_EXPR && integer_zerop (arg1)
12632 && code == NE_EXPR)
12633 return non_lvalue_loc (loc, fold_convert_loc (loc, type, arg0));
12635 /* If this is an equality comparison of the address of two non-weak,
12636 unaliased symbols neither of which are extern (since we do not
12637 have access to attributes for externs), then we know the result. */
12638 if (TREE_CODE (arg0) == ADDR_EXPR
12639 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg0, 0))
12640 && ! DECL_WEAK (TREE_OPERAND (arg0, 0))
12641 && ! lookup_attribute ("alias",
12642 DECL_ATTRIBUTES (TREE_OPERAND (arg0, 0)))
12643 && ! DECL_EXTERNAL (TREE_OPERAND (arg0, 0))
12644 && TREE_CODE (arg1) == ADDR_EXPR
12645 && VAR_OR_FUNCTION_DECL_P (TREE_OPERAND (arg1, 0))
12646 && ! DECL_WEAK (TREE_OPERAND (arg1, 0))
12647 && ! lookup_attribute ("alias",
12648 DECL_ATTRIBUTES (TREE_OPERAND (arg1, 0)))
12649 && ! DECL_EXTERNAL (TREE_OPERAND (arg1, 0)))
12651 /* We know that we're looking at the address of two
12652 non-weak, unaliased, static _DECL nodes.
12654 It is both wasteful and incorrect to call operand_equal_p
12655 to compare the two ADDR_EXPR nodes. It is wasteful in that
12656 all we need to do is test pointer equality for the arguments
12657 to the two ADDR_EXPR nodes. It is incorrect to use
12658 operand_equal_p as that function is NOT equivalent to a
12659 C equality test. It can in fact return false for two
12660 objects which would test as equal using the C equality
12662 bool equal = TREE_OPERAND (arg0, 0) == TREE_OPERAND (arg1, 0);
12663 return constant_boolean_node (equal
12664 ? code == EQ_EXPR : code != EQ_EXPR,
12668 /* If this is an EQ or NE comparison of a constant with a PLUS_EXPR or
12669 a MINUS_EXPR of a constant, we can convert it into a comparison with
12670 a revised constant as long as no overflow occurs. */
12671 if (TREE_CODE (arg1) == INTEGER_CST
12672 && (TREE_CODE (arg0) == PLUS_EXPR
12673 || TREE_CODE (arg0) == MINUS_EXPR)
12674 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
12675 && 0 != (tem = const_binop (TREE_CODE (arg0) == PLUS_EXPR
12676 ? MINUS_EXPR : PLUS_EXPR,
12677 fold_convert_loc (loc, TREE_TYPE (arg0),
12679 TREE_OPERAND (arg0, 1), 0))
12680 && !TREE_OVERFLOW (tem))
12681 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12683 /* Similarly for a NEGATE_EXPR. */
12684 if (TREE_CODE (arg0) == NEGATE_EXPR
12685 && TREE_CODE (arg1) == INTEGER_CST
12686 && 0 != (tem = negate_expr (arg1))
12687 && TREE_CODE (tem) == INTEGER_CST
12688 && !TREE_OVERFLOW (tem))
12689 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), tem);
12691 /* Similarly for a BIT_XOR_EXPR; X ^ C1 == C2 is X == (C1 ^ C2). */
12692 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12693 && TREE_CODE (arg1) == INTEGER_CST
12694 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12695 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12696 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg0),
12697 fold_convert_loc (loc,
12700 TREE_OPERAND (arg0, 1)));
12702 /* Transform comparisons of the form X +- Y CMP X to Y CMP 0. */
12703 if ((TREE_CODE (arg0) == PLUS_EXPR
12704 || TREE_CODE (arg0) == POINTER_PLUS_EXPR
12705 || TREE_CODE (arg0) == MINUS_EXPR)
12706 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12707 && (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
12708 || POINTER_TYPE_P (TREE_TYPE (arg0))))
12710 tree val = TREE_OPERAND (arg0, 1);
12711 return omit_two_operands_loc (loc, type,
12712 fold_build2_loc (loc, code, type,
12714 build_int_cst (TREE_TYPE (val),
12716 TREE_OPERAND (arg0, 0), arg1);
12719 /* Transform comparisons of the form C - X CMP X if C % 2 == 1. */
12720 if (TREE_CODE (arg0) == MINUS_EXPR
12721 && TREE_CODE (TREE_OPERAND (arg0, 0)) == INTEGER_CST
12722 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0)
12723 && (TREE_INT_CST_LOW (TREE_OPERAND (arg0, 0)) & 1) == 1)
12725 return omit_two_operands_loc (loc, type,
12727 ? boolean_true_node : boolean_false_node,
12728 TREE_OPERAND (arg0, 1), arg1);
12731 /* If we have X - Y == 0, we can convert that to X == Y and similarly
12732 for !=. Don't do this for ordered comparisons due to overflow. */
12733 if (TREE_CODE (arg0) == MINUS_EXPR
12734 && integer_zerop (arg1))
12735 return fold_build2_loc (loc, code, type,
12736 TREE_OPERAND (arg0, 0), TREE_OPERAND (arg0, 1));
12738 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
12739 if (TREE_CODE (arg0) == ABS_EXPR
12740 && (integer_zerop (arg1) || real_zerop (arg1)))
12741 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0), arg1);
12743 /* If this is an EQ or NE comparison with zero and ARG0 is
12744 (1 << foo) & bar, convert it to (bar >> foo) & 1. Both require
12745 two operations, but the latter can be done in one less insn
12746 on machines that have only two-operand insns or on which a
12747 constant cannot be the first operand. */
12748 if (TREE_CODE (arg0) == BIT_AND_EXPR
12749 && integer_zerop (arg1))
12751 tree arg00 = TREE_OPERAND (arg0, 0);
12752 tree arg01 = TREE_OPERAND (arg0, 1);
12753 if (TREE_CODE (arg00) == LSHIFT_EXPR
12754 && integer_onep (TREE_OPERAND (arg00, 0)))
12756 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg00),
12757 arg01, TREE_OPERAND (arg00, 1));
12758 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12759 build_int_cst (TREE_TYPE (arg0), 1));
12760 return fold_build2_loc (loc, code, type,
12761 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12764 else if (TREE_CODE (arg01) == LSHIFT_EXPR
12765 && integer_onep (TREE_OPERAND (arg01, 0)))
12767 tree tem = fold_build2_loc (loc, RSHIFT_EXPR, TREE_TYPE (arg01),
12768 arg00, TREE_OPERAND (arg01, 1));
12769 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0), tem,
12770 build_int_cst (TREE_TYPE (arg0), 1));
12771 return fold_build2_loc (loc, code, type,
12772 fold_convert_loc (loc, TREE_TYPE (arg1), tem),
12777 /* If this is an NE or EQ comparison of zero against the result of a
12778 signed MOD operation whose second operand is a power of 2, make
12779 the MOD operation unsigned since it is simpler and equivalent. */
12780 if (integer_zerop (arg1)
12781 && !TYPE_UNSIGNED (TREE_TYPE (arg0))
12782 && (TREE_CODE (arg0) == TRUNC_MOD_EXPR
12783 || TREE_CODE (arg0) == CEIL_MOD_EXPR
12784 || TREE_CODE (arg0) == FLOOR_MOD_EXPR
12785 || TREE_CODE (arg0) == ROUND_MOD_EXPR)
12786 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12788 tree newtype = unsigned_type_for (TREE_TYPE (arg0));
12789 tree newmod = fold_build2_loc (loc, TREE_CODE (arg0), newtype,
12790 fold_convert_loc (loc, newtype,
12791 TREE_OPERAND (arg0, 0)),
12792 fold_convert_loc (loc, newtype,
12793 TREE_OPERAND (arg0, 1)));
12795 return fold_build2_loc (loc, code, type, newmod,
12796 fold_convert_loc (loc, newtype, arg1));
12799 /* Fold ((X >> C1) & C2) == 0 and ((X >> C1) & C2) != 0 where
12800 C1 is a valid shift constant, and C2 is a power of two, i.e.
12802 if (TREE_CODE (arg0) == BIT_AND_EXPR
12803 && TREE_CODE (TREE_OPERAND (arg0, 0)) == RSHIFT_EXPR
12804 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1))
12806 && integer_pow2p (TREE_OPERAND (arg0, 1))
12807 && integer_zerop (arg1))
12809 tree itype = TREE_TYPE (arg0);
12810 unsigned HOST_WIDE_INT prec = TYPE_PRECISION (itype);
12811 tree arg001 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 1);
12813 /* Check for a valid shift count. */
12814 if (TREE_INT_CST_HIGH (arg001) == 0
12815 && TREE_INT_CST_LOW (arg001) < prec)
12817 tree arg01 = TREE_OPERAND (arg0, 1);
12818 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
12819 unsigned HOST_WIDE_INT log2 = tree_log2 (arg01);
12820 /* If (C2 << C1) doesn't overflow, then ((X >> C1) & C2) != 0
12821 can be rewritten as (X & (C2 << C1)) != 0. */
12822 if ((log2 + TREE_INT_CST_LOW (arg001)) < prec)
12824 tem = fold_build2_loc (loc, LSHIFT_EXPR, itype, arg01, arg001);
12825 tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, arg000, tem);
12826 return fold_build2_loc (loc, code, type, tem, arg1);
12828 /* Otherwise, for signed (arithmetic) shifts,
12829 ((X >> C1) & C2) != 0 is rewritten as X < 0, and
12830 ((X >> C1) & C2) == 0 is rewritten as X >= 0. */
12831 else if (!TYPE_UNSIGNED (itype))
12832 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR, type,
12833 arg000, build_int_cst (itype, 0));
12834 /* Otherwise, of unsigned (logical) shifts,
12835 ((X >> C1) & C2) != 0 is rewritten as (X,false), and
12836 ((X >> C1) & C2) == 0 is rewritten as (X,true). */
12838 return omit_one_operand_loc (loc, type,
12839 code == EQ_EXPR ? integer_one_node
12840 : integer_zero_node,
12845 /* If this is an NE comparison of zero with an AND of one, remove the
12846 comparison since the AND will give the correct value. */
12847 if (code == NE_EXPR
12848 && integer_zerop (arg1)
12849 && TREE_CODE (arg0) == BIT_AND_EXPR
12850 && integer_onep (TREE_OPERAND (arg0, 1)))
12851 return fold_convert_loc (loc, type, arg0);
12853 /* If we have (A & C) == C where C is a power of 2, convert this into
12854 (A & C) != 0. Similarly for NE_EXPR. */
12855 if (TREE_CODE (arg0) == BIT_AND_EXPR
12856 && integer_pow2p (TREE_OPERAND (arg0, 1))
12857 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12858 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
12859 arg0, fold_convert_loc (loc, TREE_TYPE (arg0),
12860 integer_zero_node));
12862 /* If we have (A & C) != 0 or (A & C) == 0 and C is the sign
12863 bit, then fold the expression into A < 0 or A >= 0. */
12864 tem = fold_single_bit_test_into_sign_test (loc, code, arg0, arg1, type);
12868 /* If we have (A & C) == D where D & ~C != 0, convert this into 0.
12869 Similarly for NE_EXPR. */
12870 if (TREE_CODE (arg0) == BIT_AND_EXPR
12871 && TREE_CODE (arg1) == INTEGER_CST
12872 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12874 tree notc = fold_build1_loc (loc, BIT_NOT_EXPR,
12875 TREE_TYPE (TREE_OPERAND (arg0, 1)),
12876 TREE_OPERAND (arg0, 1));
12877 tree dandnotc = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12879 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12880 if (integer_nonzerop (dandnotc))
12881 return omit_one_operand_loc (loc, type, rslt, arg0);
12884 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
12885 Similarly for NE_EXPR. */
12886 if (TREE_CODE (arg0) == BIT_IOR_EXPR
12887 && TREE_CODE (arg1) == INTEGER_CST
12888 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12890 tree notd = fold_build1_loc (loc, BIT_NOT_EXPR, TREE_TYPE (arg1), arg1);
12891 tree candnotd = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12892 TREE_OPERAND (arg0, 1), notd);
12893 tree rslt = code == EQ_EXPR ? integer_zero_node : integer_one_node;
12894 if (integer_nonzerop (candnotd))
12895 return omit_one_operand_loc (loc, type, rslt, arg0);
12898 /* If this is a comparison of a field, we may be able to simplify it. */
12899 if ((TREE_CODE (arg0) == COMPONENT_REF
12900 || TREE_CODE (arg0) == BIT_FIELD_REF)
12901 /* Handle the constant case even without -O
12902 to make sure the warnings are given. */
12903 && (optimize || TREE_CODE (arg1) == INTEGER_CST))
12905 t1 = optimize_bit_field_compare (loc, code, type, arg0, arg1);
12910 /* Optimize comparisons of strlen vs zero to a compare of the
12911 first character of the string vs zero. To wit,
12912 strlen(ptr) == 0 => *ptr == 0
12913 strlen(ptr) != 0 => *ptr != 0
12914 Other cases should reduce to one of these two (or a constant)
12915 due to the return value of strlen being unsigned. */
12916 if (TREE_CODE (arg0) == CALL_EXPR
12917 && integer_zerop (arg1))
12919 tree fndecl = get_callee_fndecl (arg0);
12922 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
12923 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STRLEN
12924 && call_expr_nargs (arg0) == 1
12925 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (arg0, 0))) == POINTER_TYPE)
12927 tree iref = build_fold_indirect_ref_loc (loc,
12928 CALL_EXPR_ARG (arg0, 0));
12929 return fold_build2_loc (loc, code, type, iref,
12930 build_int_cst (TREE_TYPE (iref), 0));
12934 /* Fold (X >> C) != 0 into X < 0 if C is one less than the width
12935 of X. Similarly fold (X >> C) == 0 into X >= 0. */
12936 if (TREE_CODE (arg0) == RSHIFT_EXPR
12937 && integer_zerop (arg1)
12938 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12940 tree arg00 = TREE_OPERAND (arg0, 0);
12941 tree arg01 = TREE_OPERAND (arg0, 1);
12942 tree itype = TREE_TYPE (arg00);
12943 if (TREE_INT_CST_HIGH (arg01) == 0
12944 && TREE_INT_CST_LOW (arg01)
12945 == (unsigned HOST_WIDE_INT) (TYPE_PRECISION (itype) - 1))
12947 if (TYPE_UNSIGNED (itype))
12949 itype = signed_type_for (itype);
12950 arg00 = fold_convert_loc (loc, itype, arg00);
12952 return fold_build2_loc (loc, code == EQ_EXPR ? GE_EXPR : LT_EXPR,
12953 type, arg00, build_int_cst (itype, 0));
12957 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
12958 if (integer_zerop (arg1)
12959 && TREE_CODE (arg0) == BIT_XOR_EXPR)
12960 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12961 TREE_OPERAND (arg0, 1));
12963 /* (X ^ Y) == Y becomes X == 0. We know that Y has no side-effects. */
12964 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12965 && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
12966 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12967 build_int_cst (TREE_TYPE (arg1), 0));
12968 /* Likewise (X ^ Y) == X becomes Y == 0. X has no side-effects. */
12969 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12970 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
12971 && reorder_operands_p (TREE_OPERAND (arg0, 1), arg1))
12972 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 1),
12973 build_int_cst (TREE_TYPE (arg1), 0));
12975 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
12976 if (TREE_CODE (arg0) == BIT_XOR_EXPR
12977 && TREE_CODE (arg1) == INTEGER_CST
12978 && TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST)
12979 return fold_build2_loc (loc, code, type, TREE_OPERAND (arg0, 0),
12980 fold_build2_loc (loc, BIT_XOR_EXPR, TREE_TYPE (arg1),
12981 TREE_OPERAND (arg0, 1), arg1));
12983 /* Fold (~X & C) == 0 into (X & C) != 0 and (~X & C) != 0 into
12984 (X & C) == 0 when C is a single bit. */
12985 if (TREE_CODE (arg0) == BIT_AND_EXPR
12986 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_NOT_EXPR
12987 && integer_zerop (arg1)
12988 && integer_pow2p (TREE_OPERAND (arg0, 1)))
12990 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg0),
12991 TREE_OPERAND (TREE_OPERAND (arg0, 0), 0),
12992 TREE_OPERAND (arg0, 1));
12993 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR,
12997 /* Fold ((X & C) ^ C) eq/ne 0 into (X & C) ne/eq 0, when the
12998 constant C is a power of two, i.e. a single bit. */
12999 if (TREE_CODE (arg0) == BIT_XOR_EXPR
13000 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13001 && integer_zerop (arg1)
13002 && integer_pow2p (TREE_OPERAND (arg0, 1))
13003 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13004 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
13006 tree arg00 = TREE_OPERAND (arg0, 0);
13007 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
13008 arg00, build_int_cst (TREE_TYPE (arg00), 0));
13011 /* Likewise, fold ((X ^ C) & C) eq/ne 0 into (X & C) ne/eq 0,
13012 when is C is a power of two, i.e. a single bit. */
13013 if (TREE_CODE (arg0) == BIT_AND_EXPR
13014 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_XOR_EXPR
13015 && integer_zerop (arg1)
13016 && integer_pow2p (TREE_OPERAND (arg0, 1))
13017 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13018 TREE_OPERAND (arg0, 1), OEP_ONLY_CONST))
13020 tree arg000 = TREE_OPERAND (TREE_OPERAND (arg0, 0), 0);
13021 tem = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (arg000),
13022 arg000, TREE_OPERAND (arg0, 1));
13023 return fold_build2_loc (loc, code == EQ_EXPR ? NE_EXPR : EQ_EXPR, type,
13024 tem, build_int_cst (TREE_TYPE (tem), 0));
13027 if (integer_zerop (arg1)
13028 && tree_expr_nonzero_p (arg0))
13030 tree res = constant_boolean_node (code==NE_EXPR, type);
13031 return omit_one_operand_loc (loc, type, res, arg0);
13034 /* Fold -X op -Y as X op Y, where op is eq/ne. */
13035 if (TREE_CODE (arg0) == NEGATE_EXPR
13036 && TREE_CODE (arg1) == NEGATE_EXPR)
13037 return fold_build2_loc (loc, code, type,
13038 TREE_OPERAND (arg0, 0),
13039 TREE_OPERAND (arg1, 0));
13041 /* Fold (X & C) op (Y & C) as (X ^ Y) & C op 0", and symmetries. */
13042 if (TREE_CODE (arg0) == BIT_AND_EXPR
13043 && TREE_CODE (arg1) == BIT_AND_EXPR)
13045 tree arg00 = TREE_OPERAND (arg0, 0);
13046 tree arg01 = TREE_OPERAND (arg0, 1);
13047 tree arg10 = TREE_OPERAND (arg1, 0);
13048 tree arg11 = TREE_OPERAND (arg1, 1);
13049 tree itype = TREE_TYPE (arg0);
13051 if (operand_equal_p (arg01, arg11, 0))
13052 return fold_build2_loc (loc, code, type,
13053 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13054 fold_build2_loc (loc,
13055 BIT_XOR_EXPR, itype,
13058 build_int_cst (itype, 0));
13060 if (operand_equal_p (arg01, arg10, 0))
13061 return fold_build2_loc (loc, code, type,
13062 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13063 fold_build2_loc (loc,
13064 BIT_XOR_EXPR, itype,
13067 build_int_cst (itype, 0));
13069 if (operand_equal_p (arg00, arg11, 0))
13070 return fold_build2_loc (loc, code, type,
13071 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13072 fold_build2_loc (loc,
13073 BIT_XOR_EXPR, itype,
13076 build_int_cst (itype, 0));
13078 if (operand_equal_p (arg00, arg10, 0))
13079 return fold_build2_loc (loc, code, type,
13080 fold_build2_loc (loc, BIT_AND_EXPR, itype,
13081 fold_build2_loc (loc,
13082 BIT_XOR_EXPR, itype,
13085 build_int_cst (itype, 0));
13088 if (TREE_CODE (arg0) == BIT_XOR_EXPR
13089 && TREE_CODE (arg1) == BIT_XOR_EXPR)
13091 tree arg00 = TREE_OPERAND (arg0, 0);
13092 tree arg01 = TREE_OPERAND (arg0, 1);
13093 tree arg10 = TREE_OPERAND (arg1, 0);
13094 tree arg11 = TREE_OPERAND (arg1, 1);
13095 tree itype = TREE_TYPE (arg0);
13097 /* Optimize (X ^ Z) op (Y ^ Z) as X op Y, and symmetries.
13098 operand_equal_p guarantees no side-effects so we don't need
13099 to use omit_one_operand on Z. */
13100 if (operand_equal_p (arg01, arg11, 0))
13101 return fold_build2_loc (loc, code, type, arg00, arg10);
13102 if (operand_equal_p (arg01, arg10, 0))
13103 return fold_build2_loc (loc, code, type, arg00, arg11);
13104 if (operand_equal_p (arg00, arg11, 0))
13105 return fold_build2_loc (loc, code, type, arg01, arg10);
13106 if (operand_equal_p (arg00, arg10, 0))
13107 return fold_build2_loc (loc, code, type, arg01, arg11);
13109 /* Optimize (X ^ C1) op (Y ^ C2) as (X ^ (C1 ^ C2)) op Y. */
13110 if (TREE_CODE (arg01) == INTEGER_CST
13111 && TREE_CODE (arg11) == INTEGER_CST)
13112 return fold_build2_loc (loc, code, type,
13113 fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00,
13114 fold_build2_loc (loc,
13115 BIT_XOR_EXPR, itype,
13120 /* Attempt to simplify equality/inequality comparisons of complex
13121 values. Only lower the comparison if the result is known or
13122 can be simplified to a single scalar comparison. */
13123 if ((TREE_CODE (arg0) == COMPLEX_EXPR
13124 || TREE_CODE (arg0) == COMPLEX_CST)
13125 && (TREE_CODE (arg1) == COMPLEX_EXPR
13126 || TREE_CODE (arg1) == COMPLEX_CST))
13128 tree real0, imag0, real1, imag1;
13131 if (TREE_CODE (arg0) == COMPLEX_EXPR)
13133 real0 = TREE_OPERAND (arg0, 0);
13134 imag0 = TREE_OPERAND (arg0, 1);
13138 real0 = TREE_REALPART (arg0);
13139 imag0 = TREE_IMAGPART (arg0);
13142 if (TREE_CODE (arg1) == COMPLEX_EXPR)
13144 real1 = TREE_OPERAND (arg1, 0);
13145 imag1 = TREE_OPERAND (arg1, 1);
13149 real1 = TREE_REALPART (arg1);
13150 imag1 = TREE_IMAGPART (arg1);
13153 rcond = fold_binary_loc (loc, code, type, real0, real1);
13154 if (rcond && TREE_CODE (rcond) == INTEGER_CST)
13156 if (integer_zerop (rcond))
13158 if (code == EQ_EXPR)
13159 return omit_two_operands_loc (loc, type, boolean_false_node,
13161 return fold_build2_loc (loc, NE_EXPR, type, imag0, imag1);
13165 if (code == NE_EXPR)
13166 return omit_two_operands_loc (loc, type, boolean_true_node,
13168 return fold_build2_loc (loc, EQ_EXPR, type, imag0, imag1);
13172 icond = fold_binary_loc (loc, code, type, imag0, imag1);
13173 if (icond && TREE_CODE (icond) == INTEGER_CST)
13175 if (integer_zerop (icond))
13177 if (code == EQ_EXPR)
13178 return omit_two_operands_loc (loc, type, boolean_false_node,
13180 return fold_build2_loc (loc, NE_EXPR, type, real0, real1);
13184 if (code == NE_EXPR)
13185 return omit_two_operands_loc (loc, type, boolean_true_node,
13187 return fold_build2_loc (loc, EQ_EXPR, type, real0, real1);
13198 tem = fold_comparison (loc, code, type, op0, op1);
13199 if (tem != NULL_TREE)
13202 /* Transform comparisons of the form X +- C CMP X. */
13203 if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
13204 && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0)
13205 && ((TREE_CODE (TREE_OPERAND (arg0, 1)) == REAL_CST
13206 && !HONOR_SNANS (TYPE_MODE (TREE_TYPE (arg0))))
13207 || (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
13208 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))))
13210 tree arg01 = TREE_OPERAND (arg0, 1);
13211 enum tree_code code0 = TREE_CODE (arg0);
13214 if (TREE_CODE (arg01) == REAL_CST)
13215 is_positive = REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg01)) ? -1 : 1;
13217 is_positive = tree_int_cst_sgn (arg01);
13219 /* (X - c) > X becomes false. */
13220 if (code == GT_EXPR
13221 && ((code0 == MINUS_EXPR && is_positive >= 0)
13222 || (code0 == PLUS_EXPR && is_positive <= 0)))
13224 if (TREE_CODE (arg01) == INTEGER_CST
13225 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13226 fold_overflow_warning (("assuming signed overflow does not "
13227 "occur when assuming that (X - c) > X "
13228 "is always false"),
13229 WARN_STRICT_OVERFLOW_ALL);
13230 return constant_boolean_node (0, type);
13233 /* Likewise (X + c) < X becomes false. */
13234 if (code == LT_EXPR
13235 && ((code0 == PLUS_EXPR && is_positive >= 0)
13236 || (code0 == MINUS_EXPR && is_positive <= 0)))
13238 if (TREE_CODE (arg01) == INTEGER_CST
13239 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13240 fold_overflow_warning (("assuming signed overflow does not "
13241 "occur when assuming that "
13242 "(X + c) < X is always false"),
13243 WARN_STRICT_OVERFLOW_ALL);
13244 return constant_boolean_node (0, type);
13247 /* Convert (X - c) <= X to true. */
13248 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13250 && ((code0 == MINUS_EXPR && is_positive >= 0)
13251 || (code0 == PLUS_EXPR && is_positive <= 0)))
13253 if (TREE_CODE (arg01) == INTEGER_CST
13254 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13255 fold_overflow_warning (("assuming signed overflow does not "
13256 "occur when assuming that "
13257 "(X - c) <= X is always true"),
13258 WARN_STRICT_OVERFLOW_ALL);
13259 return constant_boolean_node (1, type);
13262 /* Convert (X + c) >= X to true. */
13263 if (!HONOR_NANS (TYPE_MODE (TREE_TYPE (arg1)))
13265 && ((code0 == PLUS_EXPR && is_positive >= 0)
13266 || (code0 == MINUS_EXPR && is_positive <= 0)))
13268 if (TREE_CODE (arg01) == INTEGER_CST
13269 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13270 fold_overflow_warning (("assuming signed overflow does not "
13271 "occur when assuming that "
13272 "(X + c) >= X is always true"),
13273 WARN_STRICT_OVERFLOW_ALL);
13274 return constant_boolean_node (1, type);
13277 if (TREE_CODE (arg01) == INTEGER_CST)
13279 /* Convert X + c > X and X - c < X to true for integers. */
13280 if (code == GT_EXPR
13281 && ((code0 == PLUS_EXPR && is_positive > 0)
13282 || (code0 == MINUS_EXPR && is_positive < 0)))
13284 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13285 fold_overflow_warning (("assuming signed overflow does "
13286 "not occur when assuming that "
13287 "(X + c) > X is always true"),
13288 WARN_STRICT_OVERFLOW_ALL);
13289 return constant_boolean_node (1, type);
13292 if (code == LT_EXPR
13293 && ((code0 == MINUS_EXPR && is_positive > 0)
13294 || (code0 == PLUS_EXPR && is_positive < 0)))
13296 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13297 fold_overflow_warning (("assuming signed overflow does "
13298 "not occur when assuming that "
13299 "(X - c) < X is always true"),
13300 WARN_STRICT_OVERFLOW_ALL);
13301 return constant_boolean_node (1, type);
13304 /* Convert X + c <= X and X - c >= X to false for integers. */
13305 if (code == LE_EXPR
13306 && ((code0 == PLUS_EXPR && is_positive > 0)
13307 || (code0 == MINUS_EXPR && is_positive < 0)))
13309 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13310 fold_overflow_warning (("assuming signed overflow does "
13311 "not occur when assuming that "
13312 "(X + c) <= X is always false"),
13313 WARN_STRICT_OVERFLOW_ALL);
13314 return constant_boolean_node (0, type);
13317 if (code == GE_EXPR
13318 && ((code0 == MINUS_EXPR && is_positive > 0)
13319 || (code0 == PLUS_EXPR && is_positive < 0)))
13321 if (TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (arg1)))
13322 fold_overflow_warning (("assuming signed overflow does "
13323 "not occur when assuming that "
13324 "(X - c) >= X is always false"),
13325 WARN_STRICT_OVERFLOW_ALL);
13326 return constant_boolean_node (0, type);
13331 /* Comparisons with the highest or lowest possible integer of
13332 the specified precision will have known values. */
13334 tree arg1_type = TREE_TYPE (arg1);
13335 unsigned int width = TYPE_PRECISION (arg1_type);
13337 if (TREE_CODE (arg1) == INTEGER_CST
13338 && width <= 2 * HOST_BITS_PER_WIDE_INT
13339 && (INTEGRAL_TYPE_P (arg1_type) || POINTER_TYPE_P (arg1_type)))
13341 HOST_WIDE_INT signed_max_hi;
13342 unsigned HOST_WIDE_INT signed_max_lo;
13343 unsigned HOST_WIDE_INT max_hi, max_lo, min_hi, min_lo;
13345 if (width <= HOST_BITS_PER_WIDE_INT)
13347 signed_max_lo = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13352 if (TYPE_UNSIGNED (arg1_type))
13354 max_lo = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13360 max_lo = signed_max_lo;
13361 min_lo = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13367 width -= HOST_BITS_PER_WIDE_INT;
13368 signed_max_lo = -1;
13369 signed_max_hi = ((unsigned HOST_WIDE_INT) 1 << (width - 1))
13374 if (TYPE_UNSIGNED (arg1_type))
13376 max_hi = ((unsigned HOST_WIDE_INT) 2 << (width - 1)) - 1;
13381 max_hi = signed_max_hi;
13382 min_hi = ((unsigned HOST_WIDE_INT) -1 << (width - 1));
13386 if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1) == max_hi
13387 && TREE_INT_CST_LOW (arg1) == max_lo)
13391 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13394 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13397 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13400 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13402 /* The GE_EXPR and LT_EXPR cases above are not normally
13403 reached because of previous transformations. */
13408 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13410 && TREE_INT_CST_LOW (arg1) == max_lo - 1)
13414 arg1 = const_binop (PLUS_EXPR, arg1,
13415 build_int_cst (TREE_TYPE (arg1), 1), 0);
13416 return fold_build2_loc (loc, EQ_EXPR, type,
13417 fold_convert_loc (loc,
13418 TREE_TYPE (arg1), arg0),
13421 arg1 = const_binop (PLUS_EXPR, arg1,
13422 build_int_cst (TREE_TYPE (arg1), 1), 0);
13423 return fold_build2_loc (loc, NE_EXPR, type,
13424 fold_convert_loc (loc, TREE_TYPE (arg1),
13430 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13432 && TREE_INT_CST_LOW (arg1) == min_lo)
13436 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13439 return fold_build2_loc (loc, EQ_EXPR, type, op0, op1);
13442 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13445 return fold_build2_loc (loc, NE_EXPR, type, op0, op1);
13450 else if ((unsigned HOST_WIDE_INT) TREE_INT_CST_HIGH (arg1)
13452 && TREE_INT_CST_LOW (arg1) == min_lo + 1)
13456 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
13457 return fold_build2_loc (loc, NE_EXPR, type,
13458 fold_convert_loc (loc,
13459 TREE_TYPE (arg1), arg0),
13462 arg1 = const_binop (MINUS_EXPR, arg1, integer_one_node, 0);
13463 return fold_build2_loc (loc, EQ_EXPR, type,
13464 fold_convert_loc (loc, TREE_TYPE (arg1),
13471 else if (TREE_INT_CST_HIGH (arg1) == signed_max_hi
13472 && TREE_INT_CST_LOW (arg1) == signed_max_lo
13473 && TYPE_UNSIGNED (arg1_type)
13474 /* We will flip the signedness of the comparison operator
13475 associated with the mode of arg1, so the sign bit is
13476 specified by this mode. Check that arg1 is the signed
13477 max associated with this sign bit. */
13478 && width == GET_MODE_BITSIZE (TYPE_MODE (arg1_type))
13479 /* signed_type does not work on pointer types. */
13480 && INTEGRAL_TYPE_P (arg1_type))
13482 /* The following case also applies to X < signed_max+1
13483 and X >= signed_max+1 because previous transformations. */
13484 if (code == LE_EXPR || code == GT_EXPR)
13487 st = signed_type_for (TREE_TYPE (arg1));
13488 return fold_build2_loc (loc,
13489 code == LE_EXPR ? GE_EXPR : LT_EXPR,
13490 type, fold_convert_loc (loc, st, arg0),
13491 build_int_cst (st, 0));
13497 /* If we are comparing an ABS_EXPR with a constant, we can
13498 convert all the cases into explicit comparisons, but they may
13499 well not be faster than doing the ABS and one comparison.
13500 But ABS (X) <= C is a range comparison, which becomes a subtraction
13501 and a comparison, and is probably faster. */
13502 if (code == LE_EXPR
13503 && TREE_CODE (arg1) == INTEGER_CST
13504 && TREE_CODE (arg0) == ABS_EXPR
13505 && ! TREE_SIDE_EFFECTS (arg0)
13506 && (0 != (tem = negate_expr (arg1)))
13507 && TREE_CODE (tem) == INTEGER_CST
13508 && !TREE_OVERFLOW (tem))
13509 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13510 build2 (GE_EXPR, type,
13511 TREE_OPERAND (arg0, 0), tem),
13512 build2 (LE_EXPR, type,
13513 TREE_OPERAND (arg0, 0), arg1));
13515 /* Convert ABS_EXPR<x> >= 0 to true. */
13516 strict_overflow_p = false;
13517 if (code == GE_EXPR
13518 && (integer_zerop (arg1)
13519 || (! HONOR_NANS (TYPE_MODE (TREE_TYPE (arg0)))
13520 && real_zerop (arg1)))
13521 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13523 if (strict_overflow_p)
13524 fold_overflow_warning (("assuming signed overflow does not occur "
13525 "when simplifying comparison of "
13526 "absolute value and zero"),
13527 WARN_STRICT_OVERFLOW_CONDITIONAL);
13528 return omit_one_operand_loc (loc, type, integer_one_node, arg0);
13531 /* Convert ABS_EXPR<x> < 0 to false. */
13532 strict_overflow_p = false;
13533 if (code == LT_EXPR
13534 && (integer_zerop (arg1) || real_zerop (arg1))
13535 && tree_expr_nonnegative_warnv_p (arg0, &strict_overflow_p))
13537 if (strict_overflow_p)
13538 fold_overflow_warning (("assuming signed overflow does not occur "
13539 "when simplifying comparison of "
13540 "absolute value and zero"),
13541 WARN_STRICT_OVERFLOW_CONDITIONAL);
13542 return omit_one_operand_loc (loc, type, integer_zero_node, arg0);
13545 /* If X is unsigned, convert X < (1 << Y) into X >> Y == 0
13546 and similarly for >= into !=. */
13547 if ((code == LT_EXPR || code == GE_EXPR)
13548 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13549 && TREE_CODE (arg1) == LSHIFT_EXPR
13550 && integer_onep (TREE_OPERAND (arg1, 0)))
13552 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13553 build2 (RSHIFT_EXPR, TREE_TYPE (arg0), arg0,
13554 TREE_OPERAND (arg1, 1)),
13555 build_int_cst (TREE_TYPE (arg0), 0));
13556 goto fold_binary_exit;
13559 if ((code == LT_EXPR || code == GE_EXPR)
13560 && TYPE_UNSIGNED (TREE_TYPE (arg0))
13561 && CONVERT_EXPR_P (arg1)
13562 && TREE_CODE (TREE_OPERAND (arg1, 0)) == LSHIFT_EXPR
13563 && integer_onep (TREE_OPERAND (TREE_OPERAND (arg1, 0), 0)))
13565 tem = build2 (code == LT_EXPR ? EQ_EXPR : NE_EXPR, type,
13566 fold_convert_loc (loc, TREE_TYPE (arg0),
13567 build2 (RSHIFT_EXPR,
13568 TREE_TYPE (arg0), arg0,
13569 TREE_OPERAND (TREE_OPERAND (arg1, 0),
13571 build_int_cst (TREE_TYPE (arg0), 0));
13572 goto fold_binary_exit;
13577 case UNORDERED_EXPR:
13585 if (TREE_CODE (arg0) == REAL_CST && TREE_CODE (arg1) == REAL_CST)
13587 t1 = fold_relational_const (code, type, arg0, arg1);
13588 if (t1 != NULL_TREE)
13592 /* If the first operand is NaN, the result is constant. */
13593 if (TREE_CODE (arg0) == REAL_CST
13594 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg0))
13595 && (code != LTGT_EXPR || ! flag_trapping_math))
13597 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13598 ? integer_zero_node
13599 : integer_one_node;
13600 return omit_one_operand_loc (loc, type, t1, arg1);
13603 /* If the second operand is NaN, the result is constant. */
13604 if (TREE_CODE (arg1) == REAL_CST
13605 && REAL_VALUE_ISNAN (TREE_REAL_CST (arg1))
13606 && (code != LTGT_EXPR || ! flag_trapping_math))
13608 t1 = (code == ORDERED_EXPR || code == LTGT_EXPR)
13609 ? integer_zero_node
13610 : integer_one_node;
13611 return omit_one_operand_loc (loc, type, t1, arg0);
13614 /* Simplify unordered comparison of something with itself. */
13615 if ((code == UNLE_EXPR || code == UNGE_EXPR || code == UNEQ_EXPR)
13616 && operand_equal_p (arg0, arg1, 0))
13617 return constant_boolean_node (1, type);
13619 if (code == LTGT_EXPR
13620 && !flag_trapping_math
13621 && operand_equal_p (arg0, arg1, 0))
13622 return constant_boolean_node (0, type);
13624 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
13626 tree targ0 = strip_float_extensions (arg0);
13627 tree targ1 = strip_float_extensions (arg1);
13628 tree newtype = TREE_TYPE (targ0);
13630 if (TYPE_PRECISION (TREE_TYPE (targ1)) > TYPE_PRECISION (newtype))
13631 newtype = TREE_TYPE (targ1);
13633 if (TYPE_PRECISION (newtype) < TYPE_PRECISION (TREE_TYPE (arg0)))
13634 return fold_build2_loc (loc, code, type,
13635 fold_convert_loc (loc, newtype, targ0),
13636 fold_convert_loc (loc, newtype, targ1));
13641 case COMPOUND_EXPR:
13642 /* When pedantic, a compound expression can be neither an lvalue
13643 nor an integer constant expression. */
13644 if (TREE_SIDE_EFFECTS (arg0) || TREE_CONSTANT (arg1))
13646 /* Don't let (0, 0) be null pointer constant. */
13647 tem = integer_zerop (arg1) ? build1 (NOP_EXPR, type, arg1)
13648 : fold_convert_loc (loc, type, arg1);
13649 return pedantic_non_lvalue_loc (loc, tem);
13652 if ((TREE_CODE (arg0) == REAL_CST
13653 && TREE_CODE (arg1) == REAL_CST)
13654 || (TREE_CODE (arg0) == INTEGER_CST
13655 && TREE_CODE (arg1) == INTEGER_CST))
13656 return build_complex (type, arg0, arg1);
13660 /* An ASSERT_EXPR should never be passed to fold_binary. */
13661 gcc_unreachable ();
13665 } /* switch (code) */
13667 protected_set_expr_location (tem, loc);
13671 /* Callback for walk_tree, looking for LABEL_EXPR. Return *TP if it is
13672 a LABEL_EXPR; otherwise return NULL_TREE. Do not check the subtrees
13676 contains_label_1 (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
13678 switch (TREE_CODE (*tp))
13684 *walk_subtrees = 0;
13686 /* ... fall through ... */
13693 /* Return whether the sub-tree ST contains a label which is accessible from
13694 outside the sub-tree. */
13697 contains_label_p (tree st)
13700 (walk_tree_without_duplicates (&st, contains_label_1 , NULL) != NULL_TREE);
13703 /* Fold a ternary expression of code CODE and type TYPE with operands
13704 OP0, OP1, and OP2. Return the folded expression if folding is
13705 successful. Otherwise, return NULL_TREE. */
13708 fold_ternary_loc (location_t loc, enum tree_code code, tree type,
13709 tree op0, tree op1, tree op2)
13712 tree arg0 = NULL_TREE, arg1 = NULL_TREE;
13713 enum tree_code_class kind = TREE_CODE_CLASS (code);
13715 gcc_assert (IS_EXPR_CODE_CLASS (kind)
13716 && TREE_CODE_LENGTH (code) == 3);
13718 /* Strip any conversions that don't change the mode. This is safe
13719 for every expression, except for a comparison expression because
13720 its signedness is derived from its operands. So, in the latter
13721 case, only strip conversions that don't change the signedness.
13723 Note that this is done as an internal manipulation within the
13724 constant folder, in order to find the simplest representation of
13725 the arguments so that their form can be studied. In any cases,
13726 the appropriate type conversions should be put back in the tree
13727 that will get out of the constant folder. */
13742 case COMPONENT_REF:
13743 if (TREE_CODE (arg0) == CONSTRUCTOR
13744 && ! type_contains_placeholder_p (TREE_TYPE (arg0)))
13746 unsigned HOST_WIDE_INT idx;
13748 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg0), idx, field, value)
13755 /* Pedantic ANSI C says that a conditional expression is never an lvalue,
13756 so all simple results must be passed through pedantic_non_lvalue. */
13757 if (TREE_CODE (arg0) == INTEGER_CST)
13759 tree unused_op = integer_zerop (arg0) ? op1 : op2;
13760 tem = integer_zerop (arg0) ? op2 : op1;
13761 /* Only optimize constant conditions when the selected branch
13762 has the same type as the COND_EXPR. This avoids optimizing
13763 away "c ? x : throw", where the throw has a void type.
13764 Avoid throwing away that operand which contains label. */
13765 if ((!TREE_SIDE_EFFECTS (unused_op)
13766 || !contains_label_p (unused_op))
13767 && (! VOID_TYPE_P (TREE_TYPE (tem))
13768 || VOID_TYPE_P (type)))
13769 return pedantic_non_lvalue_loc (loc, tem);
13772 if (operand_equal_p (arg1, op2, 0))
13773 return pedantic_omit_one_operand_loc (loc, type, arg1, arg0);
13775 /* If we have A op B ? A : C, we may be able to convert this to a
13776 simpler expression, depending on the operation and the values
13777 of B and C. Signed zeros prevent all of these transformations,
13778 for reasons given above each one.
13780 Also try swapping the arguments and inverting the conditional. */
13781 if (COMPARISON_CLASS_P (arg0)
13782 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13783 arg1, TREE_OPERAND (arg0, 1))
13784 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (arg1))))
13786 tem = fold_cond_expr_with_comparison (loc, type, arg0, op1, op2);
13791 if (COMPARISON_CLASS_P (arg0)
13792 && operand_equal_for_comparison_p (TREE_OPERAND (arg0, 0),
13794 TREE_OPERAND (arg0, 1))
13795 && !HONOR_SIGNED_ZEROS (TYPE_MODE (TREE_TYPE (op2))))
13797 tem = fold_truth_not_expr (loc, arg0);
13798 if (tem && COMPARISON_CLASS_P (tem))
13800 tem = fold_cond_expr_with_comparison (loc, type, tem, op2, op1);
13806 /* If the second operand is simpler than the third, swap them
13807 since that produces better jump optimization results. */
13808 if (truth_value_p (TREE_CODE (arg0))
13809 && tree_swap_operands_p (op1, op2, false))
13811 /* See if this can be inverted. If it can't, possibly because
13812 it was a floating-point inequality comparison, don't do
13814 tem = fold_truth_not_expr (loc, arg0);
13816 return fold_build3_loc (loc, code, type, tem, op2, op1);
13819 /* Convert A ? 1 : 0 to simply A. */
13820 if (integer_onep (op1)
13821 && integer_zerop (op2)
13822 /* If we try to convert OP0 to our type, the
13823 call to fold will try to move the conversion inside
13824 a COND, which will recurse. In that case, the COND_EXPR
13825 is probably the best choice, so leave it alone. */
13826 && type == TREE_TYPE (arg0))
13827 return pedantic_non_lvalue_loc (loc, arg0);
13829 /* Convert A ? 0 : 1 to !A. This prefers the use of NOT_EXPR
13830 over COND_EXPR in cases such as floating point comparisons. */
13831 if (integer_zerop (op1)
13832 && integer_onep (op2)
13833 && truth_value_p (TREE_CODE (arg0)))
13834 return pedantic_non_lvalue_loc (loc,
13835 fold_convert_loc (loc, type,
13836 invert_truthvalue_loc (loc,
13839 /* A < 0 ? <sign bit of A> : 0 is simply (A & <sign bit of A>). */
13840 if (TREE_CODE (arg0) == LT_EXPR
13841 && integer_zerop (TREE_OPERAND (arg0, 1))
13842 && integer_zerop (op2)
13843 && (tem = sign_bit_p (TREE_OPERAND (arg0, 0), arg1)))
13845 /* sign_bit_p only checks ARG1 bits within A's precision.
13846 If <sign bit of A> has wider type than A, bits outside
13847 of A's precision in <sign bit of A> need to be checked.
13848 If they are all 0, this optimization needs to be done
13849 in unsigned A's type, if they are all 1 in signed A's type,
13850 otherwise this can't be done. */
13851 if (TYPE_PRECISION (TREE_TYPE (tem))
13852 < TYPE_PRECISION (TREE_TYPE (arg1))
13853 && TYPE_PRECISION (TREE_TYPE (tem))
13854 < TYPE_PRECISION (type))
13856 unsigned HOST_WIDE_INT mask_lo;
13857 HOST_WIDE_INT mask_hi;
13858 int inner_width, outer_width;
13861 inner_width = TYPE_PRECISION (TREE_TYPE (tem));
13862 outer_width = TYPE_PRECISION (TREE_TYPE (arg1));
13863 if (outer_width > TYPE_PRECISION (type))
13864 outer_width = TYPE_PRECISION (type);
13866 if (outer_width > HOST_BITS_PER_WIDE_INT)
13868 mask_hi = ((unsigned HOST_WIDE_INT) -1
13869 >> (2 * HOST_BITS_PER_WIDE_INT - outer_width));
13875 mask_lo = ((unsigned HOST_WIDE_INT) -1
13876 >> (HOST_BITS_PER_WIDE_INT - outer_width));
13878 if (inner_width > HOST_BITS_PER_WIDE_INT)
13880 mask_hi &= ~((unsigned HOST_WIDE_INT) -1
13881 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13885 mask_lo &= ~((unsigned HOST_WIDE_INT) -1
13886 >> (HOST_BITS_PER_WIDE_INT - inner_width));
13888 if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == mask_hi
13889 && (TREE_INT_CST_LOW (arg1) & mask_lo) == mask_lo)
13891 tem_type = signed_type_for (TREE_TYPE (tem));
13892 tem = fold_convert_loc (loc, tem_type, tem);
13894 else if ((TREE_INT_CST_HIGH (arg1) & mask_hi) == 0
13895 && (TREE_INT_CST_LOW (arg1) & mask_lo) == 0)
13897 tem_type = unsigned_type_for (TREE_TYPE (tem));
13898 tem = fold_convert_loc (loc, tem_type, tem);
13906 fold_convert_loc (loc, type,
13907 fold_build2_loc (loc, BIT_AND_EXPR,
13908 TREE_TYPE (tem), tem,
13909 fold_convert_loc (loc,
13914 /* (A >> N) & 1 ? (1 << N) : 0 is simply A & (1 << N). A & 1 was
13915 already handled above. */
13916 if (TREE_CODE (arg0) == BIT_AND_EXPR
13917 && integer_onep (TREE_OPERAND (arg0, 1))
13918 && integer_zerop (op2)
13919 && integer_pow2p (arg1))
13921 tree tem = TREE_OPERAND (arg0, 0);
13923 if (TREE_CODE (tem) == RSHIFT_EXPR
13924 && TREE_CODE (TREE_OPERAND (tem, 1)) == INTEGER_CST
13925 && (unsigned HOST_WIDE_INT) tree_log2 (arg1) ==
13926 TREE_INT_CST_LOW (TREE_OPERAND (tem, 1)))
13927 return fold_build2_loc (loc, BIT_AND_EXPR, type,
13928 TREE_OPERAND (tem, 0), arg1);
13931 /* A & N ? N : 0 is simply A & N if N is a power of two. This
13932 is probably obsolete because the first operand should be a
13933 truth value (that's why we have the two cases above), but let's
13934 leave it in until we can confirm this for all front-ends. */
13935 if (integer_zerop (op2)
13936 && TREE_CODE (arg0) == NE_EXPR
13937 && integer_zerop (TREE_OPERAND (arg0, 1))
13938 && integer_pow2p (arg1)
13939 && TREE_CODE (TREE_OPERAND (arg0, 0)) == BIT_AND_EXPR
13940 && operand_equal_p (TREE_OPERAND (TREE_OPERAND (arg0, 0), 1),
13941 arg1, OEP_ONLY_CONST))
13942 return pedantic_non_lvalue_loc (loc,
13943 fold_convert_loc (loc, type,
13944 TREE_OPERAND (arg0, 0)));
13946 /* Convert A ? B : 0 into A && B if A and B are truth values. */
13947 if (integer_zerop (op2)
13948 && truth_value_p (TREE_CODE (arg0))
13949 && truth_value_p (TREE_CODE (arg1)))
13950 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13951 fold_convert_loc (loc, type, arg0),
13954 /* Convert A ? B : 1 into !A || B if A and B are truth values. */
13955 if (integer_onep (op2)
13956 && truth_value_p (TREE_CODE (arg0))
13957 && truth_value_p (TREE_CODE (arg1)))
13959 /* Only perform transformation if ARG0 is easily inverted. */
13960 tem = fold_truth_not_expr (loc, arg0);
13962 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13963 fold_convert_loc (loc, type, tem),
13967 /* Convert A ? 0 : B into !A && B if A and B are truth values. */
13968 if (integer_zerop (arg1)
13969 && truth_value_p (TREE_CODE (arg0))
13970 && truth_value_p (TREE_CODE (op2)))
13972 /* Only perform transformation if ARG0 is easily inverted. */
13973 tem = fold_truth_not_expr (loc, arg0);
13975 return fold_build2_loc (loc, TRUTH_ANDIF_EXPR, type,
13976 fold_convert_loc (loc, type, tem),
13980 /* Convert A ? 1 : B into A || B if A and B are truth values. */
13981 if (integer_onep (arg1)
13982 && truth_value_p (TREE_CODE (arg0))
13983 && truth_value_p (TREE_CODE (op2)))
13984 return fold_build2_loc (loc, TRUTH_ORIF_EXPR, type,
13985 fold_convert_loc (loc, type, arg0),
13991 /* CALL_EXPRs used to be ternary exprs. Catch any mistaken uses
13992 of fold_ternary on them. */
13993 gcc_unreachable ();
13995 case BIT_FIELD_REF:
13996 if ((TREE_CODE (arg0) == VECTOR_CST
13997 || (TREE_CODE (arg0) == CONSTRUCTOR && TREE_CONSTANT (arg0)))
13998 && type == TREE_TYPE (TREE_TYPE (arg0)))
14000 unsigned HOST_WIDE_INT width = tree_low_cst (arg1, 1);
14001 unsigned HOST_WIDE_INT idx = tree_low_cst (op2, 1);
14004 && simple_cst_equal (arg1, TYPE_SIZE (type)) == 1
14005 && (idx % width) == 0
14006 && (idx = idx / width)
14007 < TYPE_VECTOR_SUBPARTS (TREE_TYPE (arg0)))
14009 tree elements = NULL_TREE;
14011 if (TREE_CODE (arg0) == VECTOR_CST)
14012 elements = TREE_VECTOR_CST_ELTS (arg0);
14015 unsigned HOST_WIDE_INT idx;
14018 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg0), idx, value)
14019 elements = tree_cons (NULL_TREE, value, elements);
14021 while (idx-- > 0 && elements)
14022 elements = TREE_CHAIN (elements);
14024 return TREE_VALUE (elements);
14026 return fold_convert_loc (loc, type, integer_zero_node);
14030 /* A bit-field-ref that referenced the full argument can be stripped. */
14031 if (INTEGRAL_TYPE_P (TREE_TYPE (arg0))
14032 && TYPE_PRECISION (TREE_TYPE (arg0)) == tree_low_cst (arg1, 1)
14033 && integer_zerop (op2))
14034 return fold_convert_loc (loc, type, arg0);
14040 } /* switch (code) */
14043 /* Perform constant folding and related simplification of EXPR.
14044 The related simplifications include x*1 => x, x*0 => 0, etc.,
14045 and application of the associative law.
14046 NOP_EXPR conversions may be removed freely (as long as we
14047 are careful not to change the type of the overall expression).
14048 We cannot simplify through a CONVERT_EXPR, FIX_EXPR or FLOAT_EXPR,
14049 but we can constant-fold them if they have constant operands. */
14051 #ifdef ENABLE_FOLD_CHECKING
14052 # define fold(x) fold_1 (x)
14053 static tree fold_1 (tree);
14059 const tree t = expr;
14060 enum tree_code code = TREE_CODE (t);
14061 enum tree_code_class kind = TREE_CODE_CLASS (code);
14063 location_t loc = EXPR_LOCATION (expr);
14065 /* Return right away if a constant. */
14066 if (kind == tcc_constant)
14069 /* CALL_EXPR-like objects with variable numbers of operands are
14070 treated specially. */
14071 if (kind == tcc_vl_exp)
14073 if (code == CALL_EXPR)
14075 tem = fold_call_expr (loc, expr, false);
14076 return tem ? tem : expr;
14081 if (IS_EXPR_CODE_CLASS (kind))
14083 tree type = TREE_TYPE (t);
14084 tree op0, op1, op2;
14086 switch (TREE_CODE_LENGTH (code))
14089 op0 = TREE_OPERAND (t, 0);
14090 tem = fold_unary_loc (loc, code, type, op0);
14091 return tem ? tem : expr;
14093 op0 = TREE_OPERAND (t, 0);
14094 op1 = TREE_OPERAND (t, 1);
14095 tem = fold_binary_loc (loc, code, type, op0, op1);
14096 return tem ? tem : expr;
14098 op0 = TREE_OPERAND (t, 0);
14099 op1 = TREE_OPERAND (t, 1);
14100 op2 = TREE_OPERAND (t, 2);
14101 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14102 return tem ? tem : expr;
14112 tree op0 = TREE_OPERAND (t, 0);
14113 tree op1 = TREE_OPERAND (t, 1);
14115 if (TREE_CODE (op1) == INTEGER_CST
14116 && TREE_CODE (op0) == CONSTRUCTOR
14117 && ! type_contains_placeholder_p (TREE_TYPE (op0)))
14119 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (op0);
14120 unsigned HOST_WIDE_INT end = VEC_length (constructor_elt, elts);
14121 unsigned HOST_WIDE_INT begin = 0;
14123 /* Find a matching index by means of a binary search. */
14124 while (begin != end)
14126 unsigned HOST_WIDE_INT middle = (begin + end) / 2;
14127 tree index = VEC_index (constructor_elt, elts, middle)->index;
14129 if (TREE_CODE (index) == INTEGER_CST
14130 && tree_int_cst_lt (index, op1))
14131 begin = middle + 1;
14132 else if (TREE_CODE (index) == INTEGER_CST
14133 && tree_int_cst_lt (op1, index))
14135 else if (TREE_CODE (index) == RANGE_EXPR
14136 && tree_int_cst_lt (TREE_OPERAND (index, 1), op1))
14137 begin = middle + 1;
14138 else if (TREE_CODE (index) == RANGE_EXPR
14139 && tree_int_cst_lt (op1, TREE_OPERAND (index, 0)))
14142 return VEC_index (constructor_elt, elts, middle)->value;
14150 return fold (DECL_INITIAL (t));
14154 } /* switch (code) */
14157 #ifdef ENABLE_FOLD_CHECKING
14160 static void fold_checksum_tree (const_tree, struct md5_ctx *, htab_t);
14161 static void fold_check_failed (const_tree, const_tree);
14162 void print_fold_checksum (const_tree);
14164 /* When --enable-checking=fold, compute a digest of expr before
14165 and after actual fold call to see if fold did not accidentally
14166 change original expr. */
14172 struct md5_ctx ctx;
14173 unsigned char checksum_before[16], checksum_after[16];
14176 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14177 md5_init_ctx (&ctx);
14178 fold_checksum_tree (expr, &ctx, ht);
14179 md5_finish_ctx (&ctx, checksum_before);
14182 ret = fold_1 (expr);
14184 md5_init_ctx (&ctx);
14185 fold_checksum_tree (expr, &ctx, ht);
14186 md5_finish_ctx (&ctx, checksum_after);
14189 if (memcmp (checksum_before, checksum_after, 16))
14190 fold_check_failed (expr, ret);
14196 print_fold_checksum (const_tree expr)
14198 struct md5_ctx ctx;
14199 unsigned char checksum[16], cnt;
14202 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14203 md5_init_ctx (&ctx);
14204 fold_checksum_tree (expr, &ctx, ht);
14205 md5_finish_ctx (&ctx, checksum);
14207 for (cnt = 0; cnt < 16; ++cnt)
14208 fprintf (stderr, "%02x", checksum[cnt]);
14209 putc ('\n', stderr);
14213 fold_check_failed (const_tree expr ATTRIBUTE_UNUSED, const_tree ret ATTRIBUTE_UNUSED)
14215 internal_error ("fold check: original tree changed by fold");
14219 fold_checksum_tree (const_tree expr, struct md5_ctx *ctx, htab_t ht)
14222 enum tree_code code;
14223 union tree_node buf;
14228 gcc_assert ((sizeof (struct tree_exp) + 5 * sizeof (tree)
14229 <= sizeof (struct tree_function_decl))
14230 && sizeof (struct tree_type) <= sizeof (struct tree_function_decl));
14233 slot = (const void **) htab_find_slot (ht, expr, INSERT);
14237 code = TREE_CODE (expr);
14238 if (TREE_CODE_CLASS (code) == tcc_declaration
14239 && DECL_ASSEMBLER_NAME_SET_P (expr))
14241 /* Allow DECL_ASSEMBLER_NAME to be modified. */
14242 memcpy ((char *) &buf, expr, tree_size (expr));
14243 SET_DECL_ASSEMBLER_NAME ((tree)&buf, NULL);
14244 expr = (tree) &buf;
14246 else if (TREE_CODE_CLASS (code) == tcc_type
14247 && (TYPE_POINTER_TO (expr)
14248 || TYPE_REFERENCE_TO (expr)
14249 || TYPE_CACHED_VALUES_P (expr)
14250 || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
14251 || TYPE_NEXT_VARIANT (expr)))
14253 /* Allow these fields to be modified. */
14255 memcpy ((char *) &buf, expr, tree_size (expr));
14256 expr = tmp = (tree) &buf;
14257 TYPE_CONTAINS_PLACEHOLDER_INTERNAL (tmp) = 0;
14258 TYPE_POINTER_TO (tmp) = NULL;
14259 TYPE_REFERENCE_TO (tmp) = NULL;
14260 TYPE_NEXT_VARIANT (tmp) = NULL;
14261 if (TYPE_CACHED_VALUES_P (tmp))
14263 TYPE_CACHED_VALUES_P (tmp) = 0;
14264 TYPE_CACHED_VALUES (tmp) = NULL;
14267 md5_process_bytes (expr, tree_size (expr), ctx);
14268 fold_checksum_tree (TREE_TYPE (expr), ctx, ht);
14269 if (TREE_CODE_CLASS (code) != tcc_type
14270 && TREE_CODE_CLASS (code) != tcc_declaration
14271 && code != TREE_LIST
14272 && code != SSA_NAME)
14273 fold_checksum_tree (TREE_CHAIN (expr), ctx, ht);
14274 switch (TREE_CODE_CLASS (code))
14280 md5_process_bytes (TREE_STRING_POINTER (expr),
14281 TREE_STRING_LENGTH (expr), ctx);
14284 fold_checksum_tree (TREE_REALPART (expr), ctx, ht);
14285 fold_checksum_tree (TREE_IMAGPART (expr), ctx, ht);
14288 fold_checksum_tree (TREE_VECTOR_CST_ELTS (expr), ctx, ht);
14294 case tcc_exceptional:
14298 fold_checksum_tree (TREE_PURPOSE (expr), ctx, ht);
14299 fold_checksum_tree (TREE_VALUE (expr), ctx, ht);
14300 expr = TREE_CHAIN (expr);
14301 goto recursive_label;
14304 for (i = 0; i < TREE_VEC_LENGTH (expr); ++i)
14305 fold_checksum_tree (TREE_VEC_ELT (expr, i), ctx, ht);
14311 case tcc_expression:
14312 case tcc_reference:
14313 case tcc_comparison:
14316 case tcc_statement:
14318 len = TREE_OPERAND_LENGTH (expr);
14319 for (i = 0; i < len; ++i)
14320 fold_checksum_tree (TREE_OPERAND (expr, i), ctx, ht);
14322 case tcc_declaration:
14323 fold_checksum_tree (DECL_NAME (expr), ctx, ht);
14324 fold_checksum_tree (DECL_CONTEXT (expr), ctx, ht);
14325 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_COMMON))
14327 fold_checksum_tree (DECL_SIZE (expr), ctx, ht);
14328 fold_checksum_tree (DECL_SIZE_UNIT (expr), ctx, ht);
14329 fold_checksum_tree (DECL_INITIAL (expr), ctx, ht);
14330 fold_checksum_tree (DECL_ABSTRACT_ORIGIN (expr), ctx, ht);
14331 fold_checksum_tree (DECL_ATTRIBUTES (expr), ctx, ht);
14333 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_WITH_VIS))
14334 fold_checksum_tree (DECL_SECTION_NAME (expr), ctx, ht);
14336 if (CODE_CONTAINS_STRUCT (TREE_CODE (expr), TS_DECL_NON_COMMON))
14338 fold_checksum_tree (DECL_VINDEX (expr), ctx, ht);
14339 fold_checksum_tree (DECL_RESULT_FLD (expr), ctx, ht);
14340 fold_checksum_tree (DECL_ARGUMENT_FLD (expr), ctx, ht);
14344 if (TREE_CODE (expr) == ENUMERAL_TYPE)
14345 fold_checksum_tree (TYPE_VALUES (expr), ctx, ht);
14346 fold_checksum_tree (TYPE_SIZE (expr), ctx, ht);
14347 fold_checksum_tree (TYPE_SIZE_UNIT (expr), ctx, ht);
14348 fold_checksum_tree (TYPE_ATTRIBUTES (expr), ctx, ht);
14349 fold_checksum_tree (TYPE_NAME (expr), ctx, ht);
14350 if (INTEGRAL_TYPE_P (expr)
14351 || SCALAR_FLOAT_TYPE_P (expr))
14353 fold_checksum_tree (TYPE_MIN_VALUE (expr), ctx, ht);
14354 fold_checksum_tree (TYPE_MAX_VALUE (expr), ctx, ht);
14356 fold_checksum_tree (TYPE_MAIN_VARIANT (expr), ctx, ht);
14357 if (TREE_CODE (expr) == RECORD_TYPE
14358 || TREE_CODE (expr) == UNION_TYPE
14359 || TREE_CODE (expr) == QUAL_UNION_TYPE)
14360 fold_checksum_tree (TYPE_BINFO (expr), ctx, ht);
14361 fold_checksum_tree (TYPE_CONTEXT (expr), ctx, ht);
14368 /* Helper function for outputting the checksum of a tree T. When
14369 debugging with gdb, you can "define mynext" to be "next" followed
14370 by "call debug_fold_checksum (op0)", then just trace down till the
14374 debug_fold_checksum (const_tree t)
14377 unsigned char checksum[16];
14378 struct md5_ctx ctx;
14379 htab_t ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14381 md5_init_ctx (&ctx);
14382 fold_checksum_tree (t, &ctx, ht);
14383 md5_finish_ctx (&ctx, checksum);
14386 for (i = 0; i < 16; i++)
14387 fprintf (stderr, "%d ", checksum[i]);
14389 fprintf (stderr, "\n");
14394 /* Fold a unary tree expression with code CODE of type TYPE with an
14395 operand OP0. LOC is the location of the resulting expression.
14396 Return a folded expression if successful. Otherwise, return a tree
14397 expression with code CODE of type TYPE with an operand OP0. */
14400 fold_build1_stat_loc (location_t loc,
14401 enum tree_code code, tree type, tree op0 MEM_STAT_DECL)
14404 #ifdef ENABLE_FOLD_CHECKING
14405 unsigned char checksum_before[16], checksum_after[16];
14406 struct md5_ctx ctx;
14409 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14410 md5_init_ctx (&ctx);
14411 fold_checksum_tree (op0, &ctx, ht);
14412 md5_finish_ctx (&ctx, checksum_before);
14416 tem = fold_unary_loc (loc, code, type, op0);
14419 tem = build1_stat (code, type, op0 PASS_MEM_STAT);
14420 SET_EXPR_LOCATION (tem, loc);
14423 #ifdef ENABLE_FOLD_CHECKING
14424 md5_init_ctx (&ctx);
14425 fold_checksum_tree (op0, &ctx, ht);
14426 md5_finish_ctx (&ctx, checksum_after);
14429 if (memcmp (checksum_before, checksum_after, 16))
14430 fold_check_failed (op0, tem);
14435 /* Fold a binary tree expression with code CODE of type TYPE with
14436 operands OP0 and OP1. LOC is the location of the resulting
14437 expression. Return a folded expression if successful. Otherwise,
14438 return a tree expression with code CODE of type TYPE with operands
14442 fold_build2_stat_loc (location_t loc,
14443 enum tree_code code, tree type, tree op0, tree op1
14447 #ifdef ENABLE_FOLD_CHECKING
14448 unsigned char checksum_before_op0[16],
14449 checksum_before_op1[16],
14450 checksum_after_op0[16],
14451 checksum_after_op1[16];
14452 struct md5_ctx ctx;
14455 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14456 md5_init_ctx (&ctx);
14457 fold_checksum_tree (op0, &ctx, ht);
14458 md5_finish_ctx (&ctx, checksum_before_op0);
14461 md5_init_ctx (&ctx);
14462 fold_checksum_tree (op1, &ctx, ht);
14463 md5_finish_ctx (&ctx, checksum_before_op1);
14467 tem = fold_binary_loc (loc, code, type, op0, op1);
14470 tem = build2_stat (code, type, op0, op1 PASS_MEM_STAT);
14471 SET_EXPR_LOCATION (tem, loc);
14474 #ifdef ENABLE_FOLD_CHECKING
14475 md5_init_ctx (&ctx);
14476 fold_checksum_tree (op0, &ctx, ht);
14477 md5_finish_ctx (&ctx, checksum_after_op0);
14480 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14481 fold_check_failed (op0, tem);
14483 md5_init_ctx (&ctx);
14484 fold_checksum_tree (op1, &ctx, ht);
14485 md5_finish_ctx (&ctx, checksum_after_op1);
14488 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14489 fold_check_failed (op1, tem);
14494 /* Fold a ternary tree expression with code CODE of type TYPE with
14495 operands OP0, OP1, and OP2. Return a folded expression if
14496 successful. Otherwise, return a tree expression with code CODE of
14497 type TYPE with operands OP0, OP1, and OP2. */
14500 fold_build3_stat_loc (location_t loc, enum tree_code code, tree type,
14501 tree op0, tree op1, tree op2 MEM_STAT_DECL)
14504 #ifdef ENABLE_FOLD_CHECKING
14505 unsigned char checksum_before_op0[16],
14506 checksum_before_op1[16],
14507 checksum_before_op2[16],
14508 checksum_after_op0[16],
14509 checksum_after_op1[16],
14510 checksum_after_op2[16];
14511 struct md5_ctx ctx;
14514 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14515 md5_init_ctx (&ctx);
14516 fold_checksum_tree (op0, &ctx, ht);
14517 md5_finish_ctx (&ctx, checksum_before_op0);
14520 md5_init_ctx (&ctx);
14521 fold_checksum_tree (op1, &ctx, ht);
14522 md5_finish_ctx (&ctx, checksum_before_op1);
14525 md5_init_ctx (&ctx);
14526 fold_checksum_tree (op2, &ctx, ht);
14527 md5_finish_ctx (&ctx, checksum_before_op2);
14531 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
14532 tem = fold_ternary_loc (loc, code, type, op0, op1, op2);
14535 tem = build3_stat (code, type, op0, op1, op2 PASS_MEM_STAT);
14536 SET_EXPR_LOCATION (tem, loc);
14539 #ifdef ENABLE_FOLD_CHECKING
14540 md5_init_ctx (&ctx);
14541 fold_checksum_tree (op0, &ctx, ht);
14542 md5_finish_ctx (&ctx, checksum_after_op0);
14545 if (memcmp (checksum_before_op0, checksum_after_op0, 16))
14546 fold_check_failed (op0, tem);
14548 md5_init_ctx (&ctx);
14549 fold_checksum_tree (op1, &ctx, ht);
14550 md5_finish_ctx (&ctx, checksum_after_op1);
14553 if (memcmp (checksum_before_op1, checksum_after_op1, 16))
14554 fold_check_failed (op1, tem);
14556 md5_init_ctx (&ctx);
14557 fold_checksum_tree (op2, &ctx, ht);
14558 md5_finish_ctx (&ctx, checksum_after_op2);
14561 if (memcmp (checksum_before_op2, checksum_after_op2, 16))
14562 fold_check_failed (op2, tem);
14567 /* Fold a CALL_EXPR expression of type TYPE with operands FN and NARGS
14568 arguments in ARGARRAY, and a null static chain.
14569 Return a folded expression if successful. Otherwise, return a CALL_EXPR
14570 of type TYPE from the given operands as constructed by build_call_array. */
14573 fold_build_call_array_loc (location_t loc, tree type, tree fn,
14574 int nargs, tree *argarray)
14577 #ifdef ENABLE_FOLD_CHECKING
14578 unsigned char checksum_before_fn[16],
14579 checksum_before_arglist[16],
14580 checksum_after_fn[16],
14581 checksum_after_arglist[16];
14582 struct md5_ctx ctx;
14586 ht = htab_create (32, htab_hash_pointer, htab_eq_pointer, NULL);
14587 md5_init_ctx (&ctx);
14588 fold_checksum_tree (fn, &ctx, ht);
14589 md5_finish_ctx (&ctx, checksum_before_fn);
14592 md5_init_ctx (&ctx);
14593 for (i = 0; i < nargs; i++)
14594 fold_checksum_tree (argarray[i], &ctx, ht);
14595 md5_finish_ctx (&ctx, checksum_before_arglist);
14599 tem = fold_builtin_call_array (loc, type, fn, nargs, argarray);
14601 #ifdef ENABLE_FOLD_CHECKING
14602 md5_init_ctx (&ctx);
14603 fold_checksum_tree (fn, &ctx, ht);
14604 md5_finish_ctx (&ctx, checksum_after_fn);
14607 if (memcmp (checksum_before_fn, checksum_after_fn, 16))
14608 fold_check_failed (fn, tem);
14610 md5_init_ctx (&ctx);
14611 for (i = 0; i < nargs; i++)
14612 fold_checksum_tree (argarray[i], &ctx, ht);
14613 md5_finish_ctx (&ctx, checksum_after_arglist);
14616 if (memcmp (checksum_before_arglist, checksum_after_arglist, 16))
14617 fold_check_failed (NULL_TREE, tem);
14622 /* Perform constant folding and related simplification of initializer
14623 expression EXPR. These behave identically to "fold_buildN" but ignore
14624 potential run-time traps and exceptions that fold must preserve. */
14626 #define START_FOLD_INIT \
14627 int saved_signaling_nans = flag_signaling_nans;\
14628 int saved_trapping_math = flag_trapping_math;\
14629 int saved_rounding_math = flag_rounding_math;\
14630 int saved_trapv = flag_trapv;\
14631 int saved_folding_initializer = folding_initializer;\
14632 flag_signaling_nans = 0;\
14633 flag_trapping_math = 0;\
14634 flag_rounding_math = 0;\
14636 folding_initializer = 1;
14638 #define END_FOLD_INIT \
14639 flag_signaling_nans = saved_signaling_nans;\
14640 flag_trapping_math = saved_trapping_math;\
14641 flag_rounding_math = saved_rounding_math;\
14642 flag_trapv = saved_trapv;\
14643 folding_initializer = saved_folding_initializer;
14646 fold_build1_initializer_loc (location_t loc, enum tree_code code,
14647 tree type, tree op)
14652 result = fold_build1_loc (loc, code, type, op);
14659 fold_build2_initializer_loc (location_t loc, enum tree_code code,
14660 tree type, tree op0, tree op1)
14665 result = fold_build2_loc (loc, code, type, op0, op1);
14672 fold_build3_initializer_loc (location_t loc, enum tree_code code,
14673 tree type, tree op0, tree op1, tree op2)
14678 result = fold_build3_loc (loc, code, type, op0, op1, op2);
14685 fold_build_call_array_initializer_loc (location_t loc, tree type, tree fn,
14686 int nargs, tree *argarray)
14691 result = fold_build_call_array_loc (loc, type, fn, nargs, argarray);
14697 #undef START_FOLD_INIT
14698 #undef END_FOLD_INIT
14700 /* Determine if first argument is a multiple of second argument. Return 0 if
14701 it is not, or we cannot easily determined it to be.
14703 An example of the sort of thing we care about (at this point; this routine
14704 could surely be made more general, and expanded to do what the *_DIV_EXPR's
14705 fold cases do now) is discovering that
14707 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14713 when we know that the two SAVE_EXPR (J * 8) nodes are the same node.
14715 This code also handles discovering that
14717 SAVE_EXPR (I) * SAVE_EXPR (J * 8)
14719 is a multiple of 8 so we don't have to worry about dealing with a
14720 possible remainder.
14722 Note that we *look* inside a SAVE_EXPR only to determine how it was
14723 calculated; it is not safe for fold to do much of anything else with the
14724 internals of a SAVE_EXPR, since it cannot know when it will be evaluated
14725 at run time. For example, the latter example above *cannot* be implemented
14726 as SAVE_EXPR (I) * J or any variant thereof, since the value of J at
14727 evaluation time of the original SAVE_EXPR is not necessarily the same at
14728 the time the new expression is evaluated. The only optimization of this
14729 sort that would be valid is changing
14731 SAVE_EXPR (I) * SAVE_EXPR (SAVE_EXPR (J) * 8)
14735 SAVE_EXPR (I) * SAVE_EXPR (J)
14737 (where the same SAVE_EXPR (J) is used in the original and the
14738 transformed version). */
14741 multiple_of_p (tree type, const_tree top, const_tree bottom)
14743 if (operand_equal_p (top, bottom, 0))
14746 if (TREE_CODE (type) != INTEGER_TYPE)
14749 switch (TREE_CODE (top))
14752 /* Bitwise and provides a power of two multiple. If the mask is
14753 a multiple of BOTTOM then TOP is a multiple of BOTTOM. */
14754 if (!integer_pow2p (bottom))
14759 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14760 || multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14764 return (multiple_of_p (type, TREE_OPERAND (top, 0), bottom)
14765 && multiple_of_p (type, TREE_OPERAND (top, 1), bottom));
14768 if (TREE_CODE (TREE_OPERAND (top, 1)) == INTEGER_CST)
14772 op1 = TREE_OPERAND (top, 1);
14773 /* const_binop may not detect overflow correctly,
14774 so check for it explicitly here. */
14775 if (TYPE_PRECISION (TREE_TYPE (size_one_node))
14776 > TREE_INT_CST_LOW (op1)
14777 && TREE_INT_CST_HIGH (op1) == 0
14778 && 0 != (t1 = fold_convert (type,
14779 const_binop (LSHIFT_EXPR,
14782 && !TREE_OVERFLOW (t1))
14783 return multiple_of_p (type, t1, bottom);
14788 /* Can't handle conversions from non-integral or wider integral type. */
14789 if ((TREE_CODE (TREE_TYPE (TREE_OPERAND (top, 0))) != INTEGER_TYPE)
14790 || (TYPE_PRECISION (type)
14791 < TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (top, 0)))))
14794 /* .. fall through ... */
14797 return multiple_of_p (type, TREE_OPERAND (top, 0), bottom);
14800 if (TREE_CODE (bottom) != INTEGER_CST
14801 || integer_zerop (bottom)
14802 || (TYPE_UNSIGNED (type)
14803 && (tree_int_cst_sgn (top) < 0
14804 || tree_int_cst_sgn (bottom) < 0)))
14806 return integer_zerop (int_const_binop (TRUNC_MOD_EXPR,
14814 /* Return true if CODE or TYPE is known to be non-negative. */
14817 tree_simple_nonnegative_warnv_p (enum tree_code code, tree type)
14819 if ((TYPE_PRECISION (type) != 1 || TYPE_UNSIGNED (type))
14820 && truth_value_p (code))
14821 /* Truth values evaluate to 0 or 1, which is nonnegative unless we
14822 have a signed:1 type (where the value is -1 and 0). */
14827 /* Return true if (CODE OP0) is known to be non-negative. If the return
14828 value is based on the assumption that signed overflow is undefined,
14829 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14830 *STRICT_OVERFLOW_P. */
14833 tree_unary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14834 bool *strict_overflow_p)
14836 if (TYPE_UNSIGNED (type))
14842 /* We can't return 1 if flag_wrapv is set because
14843 ABS_EXPR<INT_MIN> = INT_MIN. */
14844 if (!INTEGRAL_TYPE_P (type))
14846 if (TYPE_OVERFLOW_UNDEFINED (type))
14848 *strict_overflow_p = true;
14853 case NON_LVALUE_EXPR:
14855 case FIX_TRUNC_EXPR:
14856 return tree_expr_nonnegative_warnv_p (op0,
14857 strict_overflow_p);
14861 tree inner_type = TREE_TYPE (op0);
14862 tree outer_type = type;
14864 if (TREE_CODE (outer_type) == REAL_TYPE)
14866 if (TREE_CODE (inner_type) == REAL_TYPE)
14867 return tree_expr_nonnegative_warnv_p (op0,
14868 strict_overflow_p);
14869 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14871 if (TYPE_UNSIGNED (inner_type))
14873 return tree_expr_nonnegative_warnv_p (op0,
14874 strict_overflow_p);
14877 else if (TREE_CODE (outer_type) == INTEGER_TYPE)
14879 if (TREE_CODE (inner_type) == REAL_TYPE)
14880 return tree_expr_nonnegative_warnv_p (op0,
14881 strict_overflow_p);
14882 if (TREE_CODE (inner_type) == INTEGER_TYPE)
14883 return TYPE_PRECISION (inner_type) < TYPE_PRECISION (outer_type)
14884 && TYPE_UNSIGNED (inner_type);
14890 return tree_simple_nonnegative_warnv_p (code, type);
14893 /* We don't know sign of `t', so be conservative and return false. */
14897 /* Return true if (CODE OP0 OP1) is known to be non-negative. If the return
14898 value is based on the assumption that signed overflow is undefined,
14899 set *STRICT_OVERFLOW_P to true; otherwise, don't change
14900 *STRICT_OVERFLOW_P. */
14903 tree_binary_nonnegative_warnv_p (enum tree_code code, tree type, tree op0,
14904 tree op1, bool *strict_overflow_p)
14906 if (TYPE_UNSIGNED (type))
14911 case POINTER_PLUS_EXPR:
14913 if (FLOAT_TYPE_P (type))
14914 return (tree_expr_nonnegative_warnv_p (op0,
14916 && tree_expr_nonnegative_warnv_p (op1,
14917 strict_overflow_p));
14919 /* zero_extend(x) + zero_extend(y) is non-negative if x and y are
14920 both unsigned and at least 2 bits shorter than the result. */
14921 if (TREE_CODE (type) == INTEGER_TYPE
14922 && TREE_CODE (op0) == NOP_EXPR
14923 && TREE_CODE (op1) == NOP_EXPR)
14925 tree inner1 = TREE_TYPE (TREE_OPERAND (op0, 0));
14926 tree inner2 = TREE_TYPE (TREE_OPERAND (op1, 0));
14927 if (TREE_CODE (inner1) == INTEGER_TYPE && TYPE_UNSIGNED (inner1)
14928 && TREE_CODE (inner2) == INTEGER_TYPE && TYPE_UNSIGNED (inner2))
14930 unsigned int prec = MAX (TYPE_PRECISION (inner1),
14931 TYPE_PRECISION (inner2)) + 1;
14932 return prec < TYPE_PRECISION (type);
14938 if (FLOAT_TYPE_P (type))
14940 /* x * x for floating point x is always non-negative. */
14941 if (operand_equal_p (op0, op1, 0))
14943 return (tree_expr_nonnegative_warnv_p (op0,
14945 && tree_expr_nonnegative_warnv_p (op1,
14946 strict_overflow_p));
14949 /* zero_extend(x) * zero_extend(y) is non-negative if x and y are
14950 both unsigned and their total bits is shorter than the result. */
14951 if (TREE_CODE (type) == INTEGER_TYPE
14952 && (TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == INTEGER_CST)
14953 && (TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == INTEGER_CST))
14955 tree inner0 = (TREE_CODE (op0) == NOP_EXPR)
14956 ? TREE_TYPE (TREE_OPERAND (op0, 0))
14958 tree inner1 = (TREE_CODE (op1) == NOP_EXPR)
14959 ? TREE_TYPE (TREE_OPERAND (op1, 0))
14962 bool unsigned0 = TYPE_UNSIGNED (inner0);
14963 bool unsigned1 = TYPE_UNSIGNED (inner1);
14965 if (TREE_CODE (op0) == INTEGER_CST)
14966 unsigned0 = unsigned0 || tree_int_cst_sgn (op0) >= 0;
14968 if (TREE_CODE (op1) == INTEGER_CST)
14969 unsigned1 = unsigned1 || tree_int_cst_sgn (op1) >= 0;
14971 if (TREE_CODE (inner0) == INTEGER_TYPE && unsigned0
14972 && TREE_CODE (inner1) == INTEGER_TYPE && unsigned1)
14974 unsigned int precision0 = (TREE_CODE (op0) == INTEGER_CST)
14975 ? tree_int_cst_min_precision (op0, /*unsignedp=*/true)
14976 : TYPE_PRECISION (inner0);
14978 unsigned int precision1 = (TREE_CODE (op1) == INTEGER_CST)
14979 ? tree_int_cst_min_precision (op1, /*unsignedp=*/true)
14980 : TYPE_PRECISION (inner1);
14982 return precision0 + precision1 < TYPE_PRECISION (type);
14989 return (tree_expr_nonnegative_warnv_p (op0,
14991 || tree_expr_nonnegative_warnv_p (op1,
14992 strict_overflow_p));
14998 case TRUNC_DIV_EXPR:
14999 case CEIL_DIV_EXPR:
15000 case FLOOR_DIV_EXPR:
15001 case ROUND_DIV_EXPR:
15002 return (tree_expr_nonnegative_warnv_p (op0,
15004 && tree_expr_nonnegative_warnv_p (op1,
15005 strict_overflow_p));
15007 case TRUNC_MOD_EXPR:
15008 case CEIL_MOD_EXPR:
15009 case FLOOR_MOD_EXPR:
15010 case ROUND_MOD_EXPR:
15011 return tree_expr_nonnegative_warnv_p (op0,
15012 strict_overflow_p);
15014 return tree_simple_nonnegative_warnv_p (code, type);
15017 /* We don't know sign of `t', so be conservative and return false. */
15021 /* Return true if T is known to be non-negative. If the return
15022 value is based on the assumption that signed overflow is undefined,
15023 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15024 *STRICT_OVERFLOW_P. */
15027 tree_single_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15029 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15032 switch (TREE_CODE (t))
15035 return tree_int_cst_sgn (t) >= 0;
15038 return ! REAL_VALUE_NEGATIVE (TREE_REAL_CST (t));
15041 return ! FIXED_VALUE_NEGATIVE (TREE_FIXED_CST (t));
15044 return (tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15046 && tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 2),
15047 strict_overflow_p));
15049 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15052 /* We don't know sign of `t', so be conservative and return false. */
15056 /* Return true if T is known to be non-negative. If the return
15057 value is based on the assumption that signed overflow is undefined,
15058 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15059 *STRICT_OVERFLOW_P. */
15062 tree_call_nonnegative_warnv_p (tree type, tree fndecl,
15063 tree arg0, tree arg1, bool *strict_overflow_p)
15065 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
15066 switch (DECL_FUNCTION_CODE (fndecl))
15068 CASE_FLT_FN (BUILT_IN_ACOS):
15069 CASE_FLT_FN (BUILT_IN_ACOSH):
15070 CASE_FLT_FN (BUILT_IN_CABS):
15071 CASE_FLT_FN (BUILT_IN_COSH):
15072 CASE_FLT_FN (BUILT_IN_ERFC):
15073 CASE_FLT_FN (BUILT_IN_EXP):
15074 CASE_FLT_FN (BUILT_IN_EXP10):
15075 CASE_FLT_FN (BUILT_IN_EXP2):
15076 CASE_FLT_FN (BUILT_IN_FABS):
15077 CASE_FLT_FN (BUILT_IN_FDIM):
15078 CASE_FLT_FN (BUILT_IN_HYPOT):
15079 CASE_FLT_FN (BUILT_IN_POW10):
15080 CASE_INT_FN (BUILT_IN_FFS):
15081 CASE_INT_FN (BUILT_IN_PARITY):
15082 CASE_INT_FN (BUILT_IN_POPCOUNT):
15083 case BUILT_IN_BSWAP32:
15084 case BUILT_IN_BSWAP64:
15088 CASE_FLT_FN (BUILT_IN_SQRT):
15089 /* sqrt(-0.0) is -0.0. */
15090 if (!HONOR_SIGNED_ZEROS (TYPE_MODE (type)))
15092 return tree_expr_nonnegative_warnv_p (arg0,
15093 strict_overflow_p);
15095 CASE_FLT_FN (BUILT_IN_ASINH):
15096 CASE_FLT_FN (BUILT_IN_ATAN):
15097 CASE_FLT_FN (BUILT_IN_ATANH):
15098 CASE_FLT_FN (BUILT_IN_CBRT):
15099 CASE_FLT_FN (BUILT_IN_CEIL):
15100 CASE_FLT_FN (BUILT_IN_ERF):
15101 CASE_FLT_FN (BUILT_IN_EXPM1):
15102 CASE_FLT_FN (BUILT_IN_FLOOR):
15103 CASE_FLT_FN (BUILT_IN_FMOD):
15104 CASE_FLT_FN (BUILT_IN_FREXP):
15105 CASE_FLT_FN (BUILT_IN_LCEIL):
15106 CASE_FLT_FN (BUILT_IN_LDEXP):
15107 CASE_FLT_FN (BUILT_IN_LFLOOR):
15108 CASE_FLT_FN (BUILT_IN_LLCEIL):
15109 CASE_FLT_FN (BUILT_IN_LLFLOOR):
15110 CASE_FLT_FN (BUILT_IN_LLRINT):
15111 CASE_FLT_FN (BUILT_IN_LLROUND):
15112 CASE_FLT_FN (BUILT_IN_LRINT):
15113 CASE_FLT_FN (BUILT_IN_LROUND):
15114 CASE_FLT_FN (BUILT_IN_MODF):
15115 CASE_FLT_FN (BUILT_IN_NEARBYINT):
15116 CASE_FLT_FN (BUILT_IN_RINT):
15117 CASE_FLT_FN (BUILT_IN_ROUND):
15118 CASE_FLT_FN (BUILT_IN_SCALB):
15119 CASE_FLT_FN (BUILT_IN_SCALBLN):
15120 CASE_FLT_FN (BUILT_IN_SCALBN):
15121 CASE_FLT_FN (BUILT_IN_SIGNBIT):
15122 CASE_FLT_FN (BUILT_IN_SIGNIFICAND):
15123 CASE_FLT_FN (BUILT_IN_SINH):
15124 CASE_FLT_FN (BUILT_IN_TANH):
15125 CASE_FLT_FN (BUILT_IN_TRUNC):
15126 /* True if the 1st argument is nonnegative. */
15127 return tree_expr_nonnegative_warnv_p (arg0,
15128 strict_overflow_p);
15130 CASE_FLT_FN (BUILT_IN_FMAX):
15131 /* True if the 1st OR 2nd arguments are nonnegative. */
15132 return (tree_expr_nonnegative_warnv_p (arg0,
15134 || (tree_expr_nonnegative_warnv_p (arg1,
15135 strict_overflow_p)));
15137 CASE_FLT_FN (BUILT_IN_FMIN):
15138 /* True if the 1st AND 2nd arguments are nonnegative. */
15139 return (tree_expr_nonnegative_warnv_p (arg0,
15141 && (tree_expr_nonnegative_warnv_p (arg1,
15142 strict_overflow_p)));
15144 CASE_FLT_FN (BUILT_IN_COPYSIGN):
15145 /* True if the 2nd argument is nonnegative. */
15146 return tree_expr_nonnegative_warnv_p (arg1,
15147 strict_overflow_p);
15149 CASE_FLT_FN (BUILT_IN_POWI):
15150 /* True if the 1st argument is nonnegative or the second
15151 argument is an even integer. */
15152 if (TREE_CODE (arg1) == INTEGER_CST
15153 && (TREE_INT_CST_LOW (arg1) & 1) == 0)
15155 return tree_expr_nonnegative_warnv_p (arg0,
15156 strict_overflow_p);
15158 CASE_FLT_FN (BUILT_IN_POW):
15159 /* True if the 1st argument is nonnegative or the second
15160 argument is an even integer valued real. */
15161 if (TREE_CODE (arg1) == REAL_CST)
15166 c = TREE_REAL_CST (arg1);
15167 n = real_to_integer (&c);
15170 REAL_VALUE_TYPE cint;
15171 real_from_integer (&cint, VOIDmode, n,
15172 n < 0 ? -1 : 0, 0);
15173 if (real_identical (&c, &cint))
15177 return tree_expr_nonnegative_warnv_p (arg0,
15178 strict_overflow_p);
15183 return tree_simple_nonnegative_warnv_p (CALL_EXPR,
15187 /* Return true if T is known to be non-negative. If the return
15188 value is based on the assumption that signed overflow is undefined,
15189 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15190 *STRICT_OVERFLOW_P. */
15193 tree_invalid_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15195 enum tree_code code = TREE_CODE (t);
15196 if (TYPE_UNSIGNED (TREE_TYPE (t)))
15203 tree temp = TARGET_EXPR_SLOT (t);
15204 t = TARGET_EXPR_INITIAL (t);
15206 /* If the initializer is non-void, then it's a normal expression
15207 that will be assigned to the slot. */
15208 if (!VOID_TYPE_P (t))
15209 return tree_expr_nonnegative_warnv_p (t, strict_overflow_p);
15211 /* Otherwise, the initializer sets the slot in some way. One common
15212 way is an assignment statement at the end of the initializer. */
15215 if (TREE_CODE (t) == BIND_EXPR)
15216 t = expr_last (BIND_EXPR_BODY (t));
15217 else if (TREE_CODE (t) == TRY_FINALLY_EXPR
15218 || TREE_CODE (t) == TRY_CATCH_EXPR)
15219 t = expr_last (TREE_OPERAND (t, 0));
15220 else if (TREE_CODE (t) == STATEMENT_LIST)
15225 if (TREE_CODE (t) == MODIFY_EXPR
15226 && TREE_OPERAND (t, 0) == temp)
15227 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15228 strict_overflow_p);
15235 tree arg0 = call_expr_nargs (t) > 0 ? CALL_EXPR_ARG (t, 0) : NULL_TREE;
15236 tree arg1 = call_expr_nargs (t) > 1 ? CALL_EXPR_ARG (t, 1) : NULL_TREE;
15238 return tree_call_nonnegative_warnv_p (TREE_TYPE (t),
15239 get_callee_fndecl (t),
15242 strict_overflow_p);
15244 case COMPOUND_EXPR:
15246 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 1),
15247 strict_overflow_p);
15249 return tree_expr_nonnegative_warnv_p (expr_last (TREE_OPERAND (t, 1)),
15250 strict_overflow_p);
15252 return tree_expr_nonnegative_warnv_p (TREE_OPERAND (t, 0),
15253 strict_overflow_p);
15256 return tree_simple_nonnegative_warnv_p (TREE_CODE (t),
15260 /* We don't know sign of `t', so be conservative and return false. */
15264 /* Return true if T is known to be non-negative. If the return
15265 value is based on the assumption that signed overflow is undefined,
15266 set *STRICT_OVERFLOW_P to true; otherwise, don't change
15267 *STRICT_OVERFLOW_P. */
15270 tree_expr_nonnegative_warnv_p (tree t, bool *strict_overflow_p)
15272 enum tree_code code;
15273 if (t == error_mark_node)
15276 code = TREE_CODE (t);
15277 switch (TREE_CODE_CLASS (code))
15280 case tcc_comparison:
15281 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15283 TREE_OPERAND (t, 0),
15284 TREE_OPERAND (t, 1),
15285 strict_overflow_p);
15288 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15290 TREE_OPERAND (t, 0),
15291 strict_overflow_p);
15294 case tcc_declaration:
15295 case tcc_reference:
15296 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15304 case TRUTH_AND_EXPR:
15305 case TRUTH_OR_EXPR:
15306 case TRUTH_XOR_EXPR:
15307 return tree_binary_nonnegative_warnv_p (TREE_CODE (t),
15309 TREE_OPERAND (t, 0),
15310 TREE_OPERAND (t, 1),
15311 strict_overflow_p);
15312 case TRUTH_NOT_EXPR:
15313 return tree_unary_nonnegative_warnv_p (TREE_CODE (t),
15315 TREE_OPERAND (t, 0),
15316 strict_overflow_p);
15323 case WITH_SIZE_EXPR:
15325 return tree_single_nonnegative_warnv_p (t, strict_overflow_p);
15328 return tree_invalid_nonnegative_warnv_p (t, strict_overflow_p);
15332 /* Return true if `t' is known to be non-negative. Handle warnings
15333 about undefined signed overflow. */
15336 tree_expr_nonnegative_p (tree t)
15338 bool ret, strict_overflow_p;
15340 strict_overflow_p = false;
15341 ret = tree_expr_nonnegative_warnv_p (t, &strict_overflow_p);
15342 if (strict_overflow_p)
15343 fold_overflow_warning (("assuming signed overflow does not occur when "
15344 "determining that expression is always "
15346 WARN_STRICT_OVERFLOW_MISC);
15351 /* Return true when (CODE OP0) is an address and is known to be nonzero.
15352 For floating point we further ensure that T is not denormal.
15353 Similar logic is present in nonzero_address in rtlanal.h.
15355 If the return value is based on the assumption that signed overflow
15356 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15357 change *STRICT_OVERFLOW_P. */
15360 tree_unary_nonzero_warnv_p (enum tree_code code, tree type, tree op0,
15361 bool *strict_overflow_p)
15366 return tree_expr_nonzero_warnv_p (op0,
15367 strict_overflow_p);
15371 tree inner_type = TREE_TYPE (op0);
15372 tree outer_type = type;
15374 return (TYPE_PRECISION (outer_type) >= TYPE_PRECISION (inner_type)
15375 && tree_expr_nonzero_warnv_p (op0,
15376 strict_overflow_p));
15380 case NON_LVALUE_EXPR:
15381 return tree_expr_nonzero_warnv_p (op0,
15382 strict_overflow_p);
15391 /* Return true when (CODE OP0 OP1) is an address and is known to be nonzero.
15392 For floating point we further ensure that T is not denormal.
15393 Similar logic is present in nonzero_address in rtlanal.h.
15395 If the return value is based on the assumption that signed overflow
15396 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15397 change *STRICT_OVERFLOW_P. */
15400 tree_binary_nonzero_warnv_p (enum tree_code code,
15403 tree op1, bool *strict_overflow_p)
15405 bool sub_strict_overflow_p;
15408 case POINTER_PLUS_EXPR:
15410 if (TYPE_OVERFLOW_UNDEFINED (type))
15412 /* With the presence of negative values it is hard
15413 to say something. */
15414 sub_strict_overflow_p = false;
15415 if (!tree_expr_nonnegative_warnv_p (op0,
15416 &sub_strict_overflow_p)
15417 || !tree_expr_nonnegative_warnv_p (op1,
15418 &sub_strict_overflow_p))
15420 /* One of operands must be positive and the other non-negative. */
15421 /* We don't set *STRICT_OVERFLOW_P here: even if this value
15422 overflows, on a twos-complement machine the sum of two
15423 nonnegative numbers can never be zero. */
15424 return (tree_expr_nonzero_warnv_p (op0,
15426 || tree_expr_nonzero_warnv_p (op1,
15427 strict_overflow_p));
15432 if (TYPE_OVERFLOW_UNDEFINED (type))
15434 if (tree_expr_nonzero_warnv_p (op0,
15436 && tree_expr_nonzero_warnv_p (op1,
15437 strict_overflow_p))
15439 *strict_overflow_p = true;
15446 sub_strict_overflow_p = false;
15447 if (tree_expr_nonzero_warnv_p (op0,
15448 &sub_strict_overflow_p)
15449 && tree_expr_nonzero_warnv_p (op1,
15450 &sub_strict_overflow_p))
15452 if (sub_strict_overflow_p)
15453 *strict_overflow_p = true;
15458 sub_strict_overflow_p = false;
15459 if (tree_expr_nonzero_warnv_p (op0,
15460 &sub_strict_overflow_p))
15462 if (sub_strict_overflow_p)
15463 *strict_overflow_p = true;
15465 /* When both operands are nonzero, then MAX must be too. */
15466 if (tree_expr_nonzero_warnv_p (op1,
15467 strict_overflow_p))
15470 /* MAX where operand 0 is positive is positive. */
15471 return tree_expr_nonnegative_warnv_p (op0,
15472 strict_overflow_p);
15474 /* MAX where operand 1 is positive is positive. */
15475 else if (tree_expr_nonzero_warnv_p (op1,
15476 &sub_strict_overflow_p)
15477 && tree_expr_nonnegative_warnv_p (op1,
15478 &sub_strict_overflow_p))
15480 if (sub_strict_overflow_p)
15481 *strict_overflow_p = true;
15487 return (tree_expr_nonzero_warnv_p (op1,
15489 || tree_expr_nonzero_warnv_p (op0,
15490 strict_overflow_p));
15499 /* Return true when T is an address and is known to be nonzero.
15500 For floating point we further ensure that T is not denormal.
15501 Similar logic is present in nonzero_address in rtlanal.h.
15503 If the return value is based on the assumption that signed overflow
15504 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15505 change *STRICT_OVERFLOW_P. */
15508 tree_single_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15510 bool sub_strict_overflow_p;
15511 switch (TREE_CODE (t))
15514 return !integer_zerop (t);
15518 tree base = get_base_address (TREE_OPERAND (t, 0));
15523 /* Weak declarations may link to NULL. Other things may also be NULL
15524 so protect with -fdelete-null-pointer-checks; but not variables
15525 allocated on the stack. */
15527 && (flag_delete_null_pointer_checks
15528 || (TREE_CODE (base) == VAR_DECL && !TREE_STATIC (base))))
15529 return !VAR_OR_FUNCTION_DECL_P (base) || !DECL_WEAK (base);
15531 /* Constants are never weak. */
15532 if (CONSTANT_CLASS_P (base))
15539 sub_strict_overflow_p = false;
15540 if (tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15541 &sub_strict_overflow_p)
15542 && tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 2),
15543 &sub_strict_overflow_p))
15545 if (sub_strict_overflow_p)
15546 *strict_overflow_p = true;
15557 /* Return true when T is an address and is known to be nonzero.
15558 For floating point we further ensure that T is not denormal.
15559 Similar logic is present in nonzero_address in rtlanal.h.
15561 If the return value is based on the assumption that signed overflow
15562 is undefined, set *STRICT_OVERFLOW_P to true; otherwise, don't
15563 change *STRICT_OVERFLOW_P. */
15566 tree_expr_nonzero_warnv_p (tree t, bool *strict_overflow_p)
15568 tree type = TREE_TYPE (t);
15569 enum tree_code code;
15571 /* Doing something useful for floating point would need more work. */
15572 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
15575 code = TREE_CODE (t);
15576 switch (TREE_CODE_CLASS (code))
15579 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15580 strict_overflow_p);
15582 case tcc_comparison:
15583 return tree_binary_nonzero_warnv_p (code, type,
15584 TREE_OPERAND (t, 0),
15585 TREE_OPERAND (t, 1),
15586 strict_overflow_p);
15588 case tcc_declaration:
15589 case tcc_reference:
15590 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15598 case TRUTH_NOT_EXPR:
15599 return tree_unary_nonzero_warnv_p (code, type, TREE_OPERAND (t, 0),
15600 strict_overflow_p);
15602 case TRUTH_AND_EXPR:
15603 case TRUTH_OR_EXPR:
15604 case TRUTH_XOR_EXPR:
15605 return tree_binary_nonzero_warnv_p (code, type,
15606 TREE_OPERAND (t, 0),
15607 TREE_OPERAND (t, 1),
15608 strict_overflow_p);
15615 case WITH_SIZE_EXPR:
15617 return tree_single_nonzero_warnv_p (t, strict_overflow_p);
15619 case COMPOUND_EXPR:
15622 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 1),
15623 strict_overflow_p);
15626 return tree_expr_nonzero_warnv_p (TREE_OPERAND (t, 0),
15627 strict_overflow_p);
15630 return alloca_call_p (t);
15638 /* Return true when T is an address and is known to be nonzero.
15639 Handle warnings about undefined signed overflow. */
15642 tree_expr_nonzero_p (tree t)
15644 bool ret, strict_overflow_p;
15646 strict_overflow_p = false;
15647 ret = tree_expr_nonzero_warnv_p (t, &strict_overflow_p);
15648 if (strict_overflow_p)
15649 fold_overflow_warning (("assuming signed overflow does not occur when "
15650 "determining that expression is always "
15652 WARN_STRICT_OVERFLOW_MISC);
15656 /* Given the components of a binary expression CODE, TYPE, OP0 and OP1,
15657 attempt to fold the expression to a constant without modifying TYPE,
15660 If the expression could be simplified to a constant, then return
15661 the constant. If the expression would not be simplified to a
15662 constant, then return NULL_TREE. */
15665 fold_binary_to_constant (enum tree_code code, tree type, tree op0, tree op1)
15667 tree tem = fold_binary (code, type, op0, op1);
15668 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15671 /* Given the components of a unary expression CODE, TYPE and OP0,
15672 attempt to fold the expression to a constant without modifying
15675 If the expression could be simplified to a constant, then return
15676 the constant. If the expression would not be simplified to a
15677 constant, then return NULL_TREE. */
15680 fold_unary_to_constant (enum tree_code code, tree type, tree op0)
15682 tree tem = fold_unary (code, type, op0);
15683 return (tem && TREE_CONSTANT (tem)) ? tem : NULL_TREE;
15686 /* If EXP represents referencing an element in a constant string
15687 (either via pointer arithmetic or array indexing), return the
15688 tree representing the value accessed, otherwise return NULL. */
15691 fold_read_from_constant_string (tree exp)
15693 if ((TREE_CODE (exp) == INDIRECT_REF
15694 || TREE_CODE (exp) == ARRAY_REF)
15695 && TREE_CODE (TREE_TYPE (exp)) == INTEGER_TYPE)
15697 tree exp1 = TREE_OPERAND (exp, 0);
15700 location_t loc = EXPR_LOCATION (exp);
15702 if (TREE_CODE (exp) == INDIRECT_REF)
15703 string = string_constant (exp1, &index);
15706 tree low_bound = array_ref_low_bound (exp);
15707 index = fold_convert_loc (loc, sizetype, TREE_OPERAND (exp, 1));
15709 /* Optimize the special-case of a zero lower bound.
15711 We convert the low_bound to sizetype to avoid some problems
15712 with constant folding. (E.g. suppose the lower bound is 1,
15713 and its mode is QI. Without the conversion,l (ARRAY
15714 +(INDEX-(unsigned char)1)) becomes ((ARRAY+(-(unsigned char)1))
15715 +INDEX), which becomes (ARRAY+255+INDEX). Oops!) */
15716 if (! integer_zerop (low_bound))
15717 index = size_diffop_loc (loc, index,
15718 fold_convert_loc (loc, sizetype, low_bound));
15724 && TYPE_MODE (TREE_TYPE (exp)) == TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))
15725 && TREE_CODE (string) == STRING_CST
15726 && TREE_CODE (index) == INTEGER_CST
15727 && compare_tree_int (index, TREE_STRING_LENGTH (string)) < 0
15728 && (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (TREE_TYPE (string))))
15730 && (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (TREE_TYPE (string)))) == 1))
15731 return build_int_cst_type (TREE_TYPE (exp),
15732 (TREE_STRING_POINTER (string)
15733 [TREE_INT_CST_LOW (index)]));
15738 /* Return the tree for neg (ARG0) when ARG0 is known to be either
15739 an integer constant, real, or fixed-point constant.
15741 TYPE is the type of the result. */
15744 fold_negate_const (tree arg0, tree type)
15746 tree t = NULL_TREE;
15748 switch (TREE_CODE (arg0))
15752 unsigned HOST_WIDE_INT low;
15753 HOST_WIDE_INT high;
15754 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15755 TREE_INT_CST_HIGH (arg0),
15757 t = force_fit_type_double (type, low, high, 1,
15758 (overflow | TREE_OVERFLOW (arg0))
15759 && !TYPE_UNSIGNED (type));
15764 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15769 FIXED_VALUE_TYPE f;
15770 bool overflow_p = fixed_arithmetic (&f, NEGATE_EXPR,
15771 &(TREE_FIXED_CST (arg0)), NULL,
15772 TYPE_SATURATING (type));
15773 t = build_fixed (type, f);
15774 /* Propagate overflow flags. */
15775 if (overflow_p | TREE_OVERFLOW (arg0))
15776 TREE_OVERFLOW (t) = 1;
15781 gcc_unreachable ();
15787 /* Return the tree for abs (ARG0) when ARG0 is known to be either
15788 an integer constant or real constant.
15790 TYPE is the type of the result. */
15793 fold_abs_const (tree arg0, tree type)
15795 tree t = NULL_TREE;
15797 switch (TREE_CODE (arg0))
15800 /* If the value is unsigned, then the absolute value is
15801 the same as the ordinary value. */
15802 if (TYPE_UNSIGNED (type))
15804 /* Similarly, if the value is non-negative. */
15805 else if (INT_CST_LT (integer_minus_one_node, arg0))
15807 /* If the value is negative, then the absolute value is
15811 unsigned HOST_WIDE_INT low;
15812 HOST_WIDE_INT high;
15813 int overflow = neg_double (TREE_INT_CST_LOW (arg0),
15814 TREE_INT_CST_HIGH (arg0),
15816 t = force_fit_type_double (type, low, high, -1,
15817 overflow | TREE_OVERFLOW (arg0));
15822 if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (arg0)))
15823 t = build_real (type, REAL_VALUE_NEGATE (TREE_REAL_CST (arg0)));
15829 gcc_unreachable ();
15835 /* Return the tree for not (ARG0) when ARG0 is known to be an integer
15836 constant. TYPE is the type of the result. */
15839 fold_not_const (tree arg0, tree type)
15841 tree t = NULL_TREE;
15843 gcc_assert (TREE_CODE (arg0) == INTEGER_CST);
15845 t = force_fit_type_double (type, ~TREE_INT_CST_LOW (arg0),
15846 ~TREE_INT_CST_HIGH (arg0), 0,
15847 TREE_OVERFLOW (arg0));
15852 /* Given CODE, a relational operator, the target type, TYPE and two
15853 constant operands OP0 and OP1, return the result of the
15854 relational operation. If the result is not a compile time
15855 constant, then return NULL_TREE. */
15858 fold_relational_const (enum tree_code code, tree type, tree op0, tree op1)
15860 int result, invert;
15862 /* From here on, the only cases we handle are when the result is
15863 known to be a constant. */
15865 if (TREE_CODE (op0) == REAL_CST && TREE_CODE (op1) == REAL_CST)
15867 const REAL_VALUE_TYPE *c0 = TREE_REAL_CST_PTR (op0);
15868 const REAL_VALUE_TYPE *c1 = TREE_REAL_CST_PTR (op1);
15870 /* Handle the cases where either operand is a NaN. */
15871 if (real_isnan (c0) || real_isnan (c1))
15881 case UNORDERED_EXPR:
15895 if (flag_trapping_math)
15901 gcc_unreachable ();
15904 return constant_boolean_node (result, type);
15907 return constant_boolean_node (real_compare (code, c0, c1), type);
15910 if (TREE_CODE (op0) == FIXED_CST && TREE_CODE (op1) == FIXED_CST)
15912 const FIXED_VALUE_TYPE *c0 = TREE_FIXED_CST_PTR (op0);
15913 const FIXED_VALUE_TYPE *c1 = TREE_FIXED_CST_PTR (op1);
15914 return constant_boolean_node (fixed_compare (code, c0, c1), type);
15917 /* Handle equality/inequality of complex constants. */
15918 if (TREE_CODE (op0) == COMPLEX_CST && TREE_CODE (op1) == COMPLEX_CST)
15920 tree rcond = fold_relational_const (code, type,
15921 TREE_REALPART (op0),
15922 TREE_REALPART (op1));
15923 tree icond = fold_relational_const (code, type,
15924 TREE_IMAGPART (op0),
15925 TREE_IMAGPART (op1));
15926 if (code == EQ_EXPR)
15927 return fold_build2 (TRUTH_ANDIF_EXPR, type, rcond, icond);
15928 else if (code == NE_EXPR)
15929 return fold_build2 (TRUTH_ORIF_EXPR, type, rcond, icond);
15934 /* From here on we only handle LT, LE, GT, GE, EQ and NE.
15936 To compute GT, swap the arguments and do LT.
15937 To compute GE, do LT and invert the result.
15938 To compute LE, swap the arguments, do LT and invert the result.
15939 To compute NE, do EQ and invert the result.
15941 Therefore, the code below must handle only EQ and LT. */
15943 if (code == LE_EXPR || code == GT_EXPR)
15948 code = swap_tree_comparison (code);
15951 /* Note that it is safe to invert for real values here because we
15952 have already handled the one case that it matters. */
15955 if (code == NE_EXPR || code == GE_EXPR)
15958 code = invert_tree_comparison (code, false);
15961 /* Compute a result for LT or EQ if args permit;
15962 Otherwise return T. */
15963 if (TREE_CODE (op0) == INTEGER_CST && TREE_CODE (op1) == INTEGER_CST)
15965 if (code == EQ_EXPR)
15966 result = tree_int_cst_equal (op0, op1);
15967 else if (TYPE_UNSIGNED (TREE_TYPE (op0)))
15968 result = INT_CST_LT_UNSIGNED (op0, op1);
15970 result = INT_CST_LT (op0, op1);
15977 return constant_boolean_node (result, type);
15980 /* If necessary, return a CLEANUP_POINT_EXPR for EXPR with the
15981 indicated TYPE. If no CLEANUP_POINT_EXPR is necessary, return EXPR
15985 fold_build_cleanup_point_expr (tree type, tree expr)
15987 /* If the expression does not have side effects then we don't have to wrap
15988 it with a cleanup point expression. */
15989 if (!TREE_SIDE_EFFECTS (expr))
15992 /* If the expression is a return, check to see if the expression inside the
15993 return has no side effects or the right hand side of the modify expression
15994 inside the return. If either don't have side effects set we don't need to
15995 wrap the expression in a cleanup point expression. Note we don't check the
15996 left hand side of the modify because it should always be a return decl. */
15997 if (TREE_CODE (expr) == RETURN_EXPR)
15999 tree op = TREE_OPERAND (expr, 0);
16000 if (!op || !TREE_SIDE_EFFECTS (op))
16002 op = TREE_OPERAND (op, 1);
16003 if (!TREE_SIDE_EFFECTS (op))
16007 return build1 (CLEANUP_POINT_EXPR, type, expr);
16010 /* Given a pointer value OP0 and a type TYPE, return a simplified version
16011 of an indirection through OP0, or NULL_TREE if no simplification is
16015 fold_indirect_ref_1 (location_t loc, tree type, tree op0)
16021 subtype = TREE_TYPE (sub);
16022 if (!POINTER_TYPE_P (subtype))
16025 if (TREE_CODE (sub) == ADDR_EXPR)
16027 tree op = TREE_OPERAND (sub, 0);
16028 tree optype = TREE_TYPE (op);
16029 /* *&CONST_DECL -> to the value of the const decl. */
16030 if (TREE_CODE (op) == CONST_DECL)
16031 return DECL_INITIAL (op);
16032 /* *&p => p; make sure to handle *&"str"[cst] here. */
16033 if (type == optype)
16035 tree fop = fold_read_from_constant_string (op);
16041 /* *(foo *)&fooarray => fooarray[0] */
16042 else if (TREE_CODE (optype) == ARRAY_TYPE
16043 && type == TREE_TYPE (optype))
16045 tree type_domain = TYPE_DOMAIN (optype);
16046 tree min_val = size_zero_node;
16047 if (type_domain && TYPE_MIN_VALUE (type_domain))
16048 min_val = TYPE_MIN_VALUE (type_domain);
16049 op0 = build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE);
16050 SET_EXPR_LOCATION (op0, loc);
16053 /* *(foo *)&complexfoo => __real__ complexfoo */
16054 else if (TREE_CODE (optype) == COMPLEX_TYPE
16055 && type == TREE_TYPE (optype))
16056 return fold_build1_loc (loc, REALPART_EXPR, type, op);
16057 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
16058 else if (TREE_CODE (optype) == VECTOR_TYPE
16059 && type == TREE_TYPE (optype))
16061 tree part_width = TYPE_SIZE (type);
16062 tree index = bitsize_int (0);
16063 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
16067 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
16068 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
16069 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
16071 tree op00 = TREE_OPERAND (sub, 0);
16072 tree op01 = TREE_OPERAND (sub, 1);
16076 op00type = TREE_TYPE (op00);
16077 if (TREE_CODE (op00) == ADDR_EXPR
16078 && TREE_CODE (TREE_TYPE (op00type)) == VECTOR_TYPE
16079 && type == TREE_TYPE (TREE_TYPE (op00type)))
16081 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
16082 tree part_width = TYPE_SIZE (type);
16083 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
16084 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
16085 tree index = bitsize_int (indexi);
16087 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (TREE_TYPE (op00type)))
16088 return fold_build3_loc (loc,
16089 BIT_FIELD_REF, type, TREE_OPERAND (op00, 0),
16090 part_width, index);
16096 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
16097 if (TREE_CODE (sub) == POINTER_PLUS_EXPR
16098 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
16100 tree op00 = TREE_OPERAND (sub, 0);
16101 tree op01 = TREE_OPERAND (sub, 1);
16105 op00type = TREE_TYPE (op00);
16106 if (TREE_CODE (op00) == ADDR_EXPR
16107 && TREE_CODE (TREE_TYPE (op00type)) == COMPLEX_TYPE
16108 && type == TREE_TYPE (TREE_TYPE (op00type)))
16110 tree size = TYPE_SIZE_UNIT (type);
16111 if (tree_int_cst_equal (size, op01))
16112 return fold_build1_loc (loc, IMAGPART_EXPR, type,
16113 TREE_OPERAND (op00, 0));
16117 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
16118 if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
16119 && type == TREE_TYPE (TREE_TYPE (subtype)))
16122 tree min_val = size_zero_node;
16123 sub = build_fold_indirect_ref_loc (loc, sub);
16124 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
16125 if (type_domain && TYPE_MIN_VALUE (type_domain))
16126 min_val = TYPE_MIN_VALUE (type_domain);
16127 op0 = build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE);
16128 SET_EXPR_LOCATION (op0, loc);
16135 /* Builds an expression for an indirection through T, simplifying some
16139 build_fold_indirect_ref_loc (location_t loc, tree t)
16141 tree type = TREE_TYPE (TREE_TYPE (t));
16142 tree sub = fold_indirect_ref_1 (loc, type, t);
16147 t = build1 (INDIRECT_REF, type, t);
16148 SET_EXPR_LOCATION (t, loc);
16152 /* Given an INDIRECT_REF T, return either T or a simplified version. */
16155 fold_indirect_ref_loc (location_t loc, tree t)
16157 tree sub = fold_indirect_ref_1 (loc, TREE_TYPE (t), TREE_OPERAND (t, 0));
16165 /* Strip non-trapping, non-side-effecting tree nodes from an expression
16166 whose result is ignored. The type of the returned tree need not be
16167 the same as the original expression. */
16170 fold_ignored_result (tree t)
16172 if (!TREE_SIDE_EFFECTS (t))
16173 return integer_zero_node;
16176 switch (TREE_CODE_CLASS (TREE_CODE (t)))
16179 t = TREE_OPERAND (t, 0);
16183 case tcc_comparison:
16184 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16185 t = TREE_OPERAND (t, 0);
16186 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0)))
16187 t = TREE_OPERAND (t, 1);
16192 case tcc_expression:
16193 switch (TREE_CODE (t))
16195 case COMPOUND_EXPR:
16196 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)))
16198 t = TREE_OPERAND (t, 0);
16202 if (TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1))
16203 || TREE_SIDE_EFFECTS (TREE_OPERAND (t, 2)))
16205 t = TREE_OPERAND (t, 0);
16218 /* Return the value of VALUE, rounded up to a multiple of DIVISOR.
16219 This can only be applied to objects of a sizetype. */
16222 round_up_loc (location_t loc, tree value, int divisor)
16224 tree div = NULL_TREE;
16226 gcc_assert (divisor > 0);
16230 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16231 have to do anything. Only do this when we are not given a const,
16232 because in that case, this check is more expensive than just
16234 if (TREE_CODE (value) != INTEGER_CST)
16236 div = build_int_cst (TREE_TYPE (value), divisor);
16238 if (multiple_of_p (TREE_TYPE (value), value, div))
16242 /* If divisor is a power of two, simplify this to bit manipulation. */
16243 if (divisor == (divisor & -divisor))
16245 if (TREE_CODE (value) == INTEGER_CST)
16247 unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (value);
16248 unsigned HOST_WIDE_INT high;
16251 if ((low & (divisor - 1)) == 0)
16254 overflow_p = TREE_OVERFLOW (value);
16255 high = TREE_INT_CST_HIGH (value);
16256 low &= ~(divisor - 1);
16265 return force_fit_type_double (TREE_TYPE (value), low, high,
16272 t = build_int_cst (TREE_TYPE (value), divisor - 1);
16273 value = size_binop_loc (loc, PLUS_EXPR, value, t);
16274 t = build_int_cst (TREE_TYPE (value), -divisor);
16275 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16281 div = build_int_cst (TREE_TYPE (value), divisor);
16282 value = size_binop_loc (loc, CEIL_DIV_EXPR, value, div);
16283 value = size_binop_loc (loc, MULT_EXPR, value, div);
16289 /* Likewise, but round down. */
16292 round_down_loc (location_t loc, tree value, int divisor)
16294 tree div = NULL_TREE;
16296 gcc_assert (divisor > 0);
16300 /* See if VALUE is already a multiple of DIVISOR. If so, we don't
16301 have to do anything. Only do this when we are not given a const,
16302 because in that case, this check is more expensive than just
16304 if (TREE_CODE (value) != INTEGER_CST)
16306 div = build_int_cst (TREE_TYPE (value), divisor);
16308 if (multiple_of_p (TREE_TYPE (value), value, div))
16312 /* If divisor is a power of two, simplify this to bit manipulation. */
16313 if (divisor == (divisor & -divisor))
16317 t = build_int_cst (TREE_TYPE (value), -divisor);
16318 value = size_binop_loc (loc, BIT_AND_EXPR, value, t);
16323 div = build_int_cst (TREE_TYPE (value), divisor);
16324 value = size_binop_loc (loc, FLOOR_DIV_EXPR, value, div);
16325 value = size_binop_loc (loc, MULT_EXPR, value, div);
16331 /* Returns the pointer to the base of the object addressed by EXP and
16332 extracts the information about the offset of the access, storing it
16333 to PBITPOS and POFFSET. */
16336 split_address_to_core_and_offset (tree exp,
16337 HOST_WIDE_INT *pbitpos, tree *poffset)
16340 enum machine_mode mode;
16341 int unsignedp, volatilep;
16342 HOST_WIDE_INT bitsize;
16343 location_t loc = EXPR_LOCATION (exp);
16345 if (TREE_CODE (exp) == ADDR_EXPR)
16347 core = get_inner_reference (TREE_OPERAND (exp, 0), &bitsize, pbitpos,
16348 poffset, &mode, &unsignedp, &volatilep,
16350 core = build_fold_addr_expr_loc (loc, core);
16356 *poffset = NULL_TREE;
16362 /* Returns true if addresses of E1 and E2 differ by a constant, false
16363 otherwise. If they do, E1 - E2 is stored in *DIFF. */
16366 ptr_difference_const (tree e1, tree e2, HOST_WIDE_INT *diff)
16369 HOST_WIDE_INT bitpos1, bitpos2;
16370 tree toffset1, toffset2, tdiff, type;
16372 core1 = split_address_to_core_and_offset (e1, &bitpos1, &toffset1);
16373 core2 = split_address_to_core_and_offset (e2, &bitpos2, &toffset2);
16375 if (bitpos1 % BITS_PER_UNIT != 0
16376 || bitpos2 % BITS_PER_UNIT != 0
16377 || !operand_equal_p (core1, core2, 0))
16380 if (toffset1 && toffset2)
16382 type = TREE_TYPE (toffset1);
16383 if (type != TREE_TYPE (toffset2))
16384 toffset2 = fold_convert (type, toffset2);
16386 tdiff = fold_build2 (MINUS_EXPR, type, toffset1, toffset2);
16387 if (!cst_and_fits_in_hwi (tdiff))
16390 *diff = int_cst_value (tdiff);
16392 else if (toffset1 || toffset2)
16394 /* If only one of the offsets is non-constant, the difference cannot
16401 *diff += (bitpos1 - bitpos2) / BITS_PER_UNIT;
16405 /* Simplify the floating point expression EXP when the sign of the
16406 result is not significant. Return NULL_TREE if no simplification
16410 fold_strip_sign_ops (tree exp)
16413 location_t loc = EXPR_LOCATION (exp);
16415 switch (TREE_CODE (exp))
16419 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16420 return arg0 ? arg0 : TREE_OPERAND (exp, 0);
16424 if (HONOR_SIGN_DEPENDENT_ROUNDING (TYPE_MODE (TREE_TYPE (exp))))
16426 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 0));
16427 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16428 if (arg0 != NULL_TREE || arg1 != NULL_TREE)
16429 return fold_build2_loc (loc, TREE_CODE (exp), TREE_TYPE (exp),
16430 arg0 ? arg0 : TREE_OPERAND (exp, 0),
16431 arg1 ? arg1 : TREE_OPERAND (exp, 1));
16434 case COMPOUND_EXPR:
16435 arg0 = TREE_OPERAND (exp, 0);
16436 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16438 return fold_build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (exp), arg0, arg1);
16442 arg0 = fold_strip_sign_ops (TREE_OPERAND (exp, 1));
16443 arg1 = fold_strip_sign_ops (TREE_OPERAND (exp, 2));
16445 return fold_build3_loc (loc,
16446 COND_EXPR, TREE_TYPE (exp), TREE_OPERAND (exp, 0),
16447 arg0 ? arg0 : TREE_OPERAND (exp, 1),
16448 arg1 ? arg1 : TREE_OPERAND (exp, 2));
16453 const enum built_in_function fcode = builtin_mathfn_code (exp);
16456 CASE_FLT_FN (BUILT_IN_COPYSIGN):
16457 /* Strip copysign function call, return the 1st argument. */
16458 arg0 = CALL_EXPR_ARG (exp, 0);
16459 arg1 = CALL_EXPR_ARG (exp, 1);
16460 return omit_one_operand_loc (loc, TREE_TYPE (exp), arg0, arg1);
16463 /* Strip sign ops from the argument of "odd" math functions. */
16464 if (negate_mathfn_p (fcode))
16466 arg0 = fold_strip_sign_ops (CALL_EXPR_ARG (exp, 0));
16468 return build_call_expr_loc (loc, get_callee_fndecl (exp), 1, arg0);