1 /* Match-and-simplify patterns for shared GENERIC and GIMPLE folding.
2 This file is consumed by genmatch which produces gimple-match.c
3 and generic-match.c from it.
5 Copyright (C) 2014-2015 Free Software Foundation, Inc.
6 Contributed by Richard Biener <rguenther@suse.de>
7 and Prathamesh Kulkarni <bilbotheelffriend@gmail.com>
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify it under
12 the terms of the GNU General Public License as published by the Free
13 Software Foundation; either version 3, or (at your option) any later
16 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
17 WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
26 /* Generic tree predicates we inherit. */
28 integer_onep integer_zerop integer_all_onesp integer_minus_onep
29 integer_each_onep integer_truep
30 real_zerop real_onep real_minus_onep
32 tree_expr_nonnegative_p
36 (define_operator_list tcc_comparison
37 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
38 (define_operator_list inverted_tcc_comparison
39 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
40 (define_operator_list inverted_tcc_comparison_with_nans
41 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
42 (define_operator_list swapped_tcc_comparison
43 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
44 (define_operator_list simple_comparison lt le eq ne ge gt)
45 (define_operator_list swapped_simple_comparison gt ge eq ne le lt)
47 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
48 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
49 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
50 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
51 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
52 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
53 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
54 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
55 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
56 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
59 /* Simplifications of operations with one constant operand and
60 simplifications to constants or single values. */
62 (for op (plus pointer_plus minus bit_ior bit_xor)
67 /* 0 +p index -> (type)index */
69 (pointer_plus integer_zerop @1)
70 (non_lvalue (convert @1)))
72 /* See if ARG1 is zero and X + ARG1 reduces to X.
73 Likewise if the operands are reversed. */
75 (plus:c @0 real_zerop@1)
76 (if (fold_real_zero_addition_p (type, @1, 0))
79 /* See if ARG1 is zero and X - ARG1 reduces to X. */
81 (minus @0 real_zerop@1)
82 (if (fold_real_zero_addition_p (type, @1, 1))
86 This is unsafe for certain floats even in non-IEEE formats.
87 In IEEE, it is unsafe because it does wrong for NaNs.
88 Also note that operand_equal_p is always false if an operand
92 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
93 { build_zero_cst (type); }))
96 (mult @0 integer_zerop@1)
99 /* Maybe fold x * 0 to 0. The expressions aren't the same
100 when x is NaN, since x * 0 is also NaN. Nor are they the
101 same in modes with signed zeros, since multiplying a
102 negative value by 0 gives -0, not +0. */
104 (mult @0 real_zerop@1)
105 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
108 /* In IEEE floating point, x*1 is not equivalent to x for snans.
109 Likewise for complex arithmetic with signed zeros. */
112 (if (!HONOR_SNANS (type)
113 && (!HONOR_SIGNED_ZEROS (type)
114 || !COMPLEX_FLOAT_TYPE_P (type)))
117 /* Transform x * -1.0 into -x. */
119 (mult @0 real_minus_onep)
120 (if (!HONOR_SNANS (type)
121 && (!HONOR_SIGNED_ZEROS (type)
122 || !COMPLEX_FLOAT_TYPE_P (type)))
125 /* Make sure to preserve divisions by zero. This is the reason why
126 we don't simplify x / x to 1 or 0 / x to 0. */
127 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
133 (for div (trunc_div ceil_div floor_div round_div exact_div)
135 (div @0 integer_minus_onep@1)
136 (if (!TYPE_UNSIGNED (type))
139 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
140 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
143 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
144 && TYPE_UNSIGNED (type))
147 /* Combine two successive divisions. Note that combining ceil_div
148 and floor_div is trickier and combining round_div even more so. */
149 (for div (trunc_div exact_div)
151 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
154 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
157 (div @0 { wide_int_to_tree (type, mul); })
158 (if (TYPE_UNSIGNED (type)
159 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED))
160 { build_zero_cst (type); })))))
162 /* Optimize A / A to 1.0 if we don't care about
163 NaNs or Infinities. */
166 (if (FLOAT_TYPE_P (type)
167 && ! HONOR_NANS (type)
168 && ! HONOR_INFINITIES (type))
169 { build_one_cst (type); }))
171 /* Optimize -A / A to -1.0 if we don't care about
172 NaNs or Infinities. */
174 (rdiv:c @0 (negate @0))
175 (if (FLOAT_TYPE_P (type)
176 && ! HONOR_NANS (type)
177 && ! HONOR_INFINITIES (type))
178 { build_minus_one_cst (type); }))
180 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
183 (if (!HONOR_SNANS (type))
186 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
188 (rdiv @0 real_minus_onep)
189 (if (!HONOR_SNANS (type))
192 /* If ARG1 is a constant, we can convert this to a multiply by the
193 reciprocal. This does not have the same rounding properties,
194 so only do this if -freciprocal-math. We can actually
195 always safely do it if ARG1 is a power of two, but it's hard to
196 tell if it is or not in a portable manner. */
197 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
201 (if (flag_reciprocal_math
204 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
206 (mult @0 { tem; } )))
207 (if (cst != COMPLEX_CST)
208 (with { tree inverse = exact_inverse (type, @1); }
210 (mult @0 { inverse; } ))))))))
212 /* Same applies to modulo operations, but fold is inconsistent here
213 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
214 (for mod (ceil_mod floor_mod round_mod trunc_mod)
215 /* 0 % X is always zero. */
217 (mod integer_zerop@0 @1)
218 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
219 (if (!integer_zerop (@1))
221 /* X % 1 is always zero. */
223 (mod @0 integer_onep)
224 { build_zero_cst (type); })
225 /* X % -1 is zero. */
227 (mod @0 integer_minus_onep@1)
228 (if (!TYPE_UNSIGNED (type))
229 { build_zero_cst (type); }))
230 /* (X % Y) % Y is just X % Y. */
232 (mod (mod@2 @0 @1) @1)
234 /* From extract_muldiv_1: (X * C1) % C2 is zero if C1 is a multiple of C2. */
236 (mod (mult @0 INTEGER_CST@1) INTEGER_CST@2)
237 (if (ANY_INTEGRAL_TYPE_P (type)
238 && TYPE_OVERFLOW_UNDEFINED (type)
239 && wi::multiple_of_p (@1, @2, TYPE_SIGN (type)))
240 { build_zero_cst (type); })))
242 /* X % -C is the same as X % C. */
244 (trunc_mod @0 INTEGER_CST@1)
245 (if (TYPE_SIGN (type) == SIGNED
246 && !TREE_OVERFLOW (@1)
248 && !TYPE_OVERFLOW_TRAPS (type)
249 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
250 && !sign_bit_p (@1, @1))
251 (trunc_mod @0 (negate @1))))
253 /* X % -Y is the same as X % Y. */
255 (trunc_mod @0 (convert? (negate @1)))
256 (if (!TYPE_UNSIGNED (type)
257 && !TYPE_OVERFLOW_TRAPS (type)
258 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
259 (trunc_mod @0 (convert @1))))
261 /* X - (X / Y) * Y is the same as X % Y. */
263 (minus (convert1? @0) (convert2? (mult (trunc_div @0 @1) @1)))
264 (if (INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
265 (trunc_mod (convert @0) (convert @1))))
267 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
268 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
269 Also optimize A % (C << N) where C is a power of 2,
270 to A & ((C << N) - 1). */
271 (match (power_of_two_cand @1)
273 (match (power_of_two_cand @1)
274 (lshift INTEGER_CST@1 @2))
275 (for mod (trunc_mod floor_mod)
277 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
278 (if ((TYPE_UNSIGNED (type)
279 || tree_expr_nonnegative_p (@0))
280 && tree_nop_conversion_p (type, TREE_TYPE (@3))
281 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
282 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
284 /* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF. */
286 (trunc_div (mult @0 integer_pow2p@1) @1)
287 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
288 (bit_and @0 { wide_int_to_tree
289 (type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
290 false, TYPE_PRECISION (type))); })))
292 /* Simplify (unsigned t / 2) * 2 -> unsigned t & ~1. */
294 (mult (trunc_div @0 integer_pow2p@1) @1)
295 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
296 (bit_and @0 (negate @1))))
298 /* X % Y is smaller than Y. */
301 (cmp (trunc_mod @0 @1) @1)
302 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
303 { constant_boolean_node (cmp == LT_EXPR, type); })))
306 (cmp @1 (trunc_mod @0 @1))
307 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
308 { constant_boolean_node (cmp == GT_EXPR, type); })))
312 (bit_ior @0 integer_all_onesp@1)
317 (bit_and @0 integer_zerop@1)
323 (for op (bit_ior bit_xor plus)
325 (op:c (convert? @0) (convert? (bit_not @0)))
326 (convert { build_all_ones_cst (TREE_TYPE (@0)); })))
331 { build_zero_cst (type); })
333 /* Canonicalize X ^ ~0 to ~X. */
335 (bit_xor @0 integer_all_onesp@1)
340 (bit_and @0 integer_all_onesp)
343 /* x & x -> x, x | x -> x */
344 (for bitop (bit_and bit_ior)
349 /* x + (x & 1) -> (x + 1) & ~1 */
351 (plus:c @0 (bit_and:s @0 integer_onep@1))
352 (bit_and (plus @0 @1) (bit_not @1)))
354 /* x & ~(x & y) -> x & ~y */
355 /* x | ~(x | y) -> x | ~y */
356 (for bitop (bit_and bit_ior)
358 (bitop:c @0 (bit_not (bitop:cs @0 @1)))
359 (bitop @0 (bit_not @1))))
361 /* (x | y) & ~x -> y & ~x */
362 /* (x & y) | ~x -> y | ~x */
363 (for bitop (bit_and bit_ior)
364 rbitop (bit_ior bit_and)
366 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
369 /* (x & y) ^ (x | y) -> x ^ y */
371 (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
374 /* (x ^ y) ^ (x | y) -> x & y */
376 (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
379 /* (x & y) + (x ^ y) -> x | y */
380 /* (x & y) | (x ^ y) -> x | y */
381 /* (x & y) ^ (x ^ y) -> x | y */
382 (for op (plus bit_ior bit_xor)
384 (op:c (bit_and @0 @1) (bit_xor @0 @1))
387 /* (x & y) + (x | y) -> x + y */
389 (plus:c (bit_and @0 @1) (bit_ior @0 @1))
392 /* (x + y) - (x | y) -> x & y */
394 (minus (plus @0 @1) (bit_ior @0 @1))
395 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
396 && !TYPE_SATURATING (type))
399 /* (x + y) - (x & y) -> x | y */
401 (minus (plus @0 @1) (bit_and @0 @1))
402 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
403 && !TYPE_SATURATING (type))
406 /* (x | y) - (x ^ y) -> x & y */
408 (minus (bit_ior @0 @1) (bit_xor @0 @1))
411 /* (x | y) - (x & y) -> x ^ y */
413 (minus (bit_ior @0 @1) (bit_and @0 @1))
416 /* (x | y) & ~(x & y) -> x ^ y */
418 (bit_and:c (bit_ior @0 @1) (bit_not (bit_and @0 @1)))
421 /* (x | y) & (~x ^ y) -> x & y */
423 (bit_and:c (bit_ior:c @0 @1) (bit_xor:c @1 (bit_not @0)))
426 /* ~x & ~y -> ~(x | y)
427 ~x | ~y -> ~(x & y) */
428 (for op (bit_and bit_ior)
429 rop (bit_ior bit_and)
431 (op (convert1? (bit_not @0)) (convert2? (bit_not @1)))
432 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
433 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
434 (bit_not (rop (convert @0) (convert @1))))))
436 /* If we are XORing or adding two BIT_AND_EXPR's, both of which are and'ing
437 with a constant, and the two constants have no bits in common,
438 we should treat this as a BIT_IOR_EXPR since this may produce more
440 (for op (bit_xor plus)
442 (op (convert1? (bit_and@4 @0 INTEGER_CST@1))
443 (convert2? (bit_and@5 @2 INTEGER_CST@3)))
444 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
445 && tree_nop_conversion_p (type, TREE_TYPE (@2))
446 && wi::bit_and (@1, @3) == 0)
447 (bit_ior (convert @4) (convert @5)))))
449 /* (X | Y) ^ X -> Y & ~ X*/
451 (bit_xor:c (convert? (bit_ior:c @0 @1)) (convert? @0))
452 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
453 (convert (bit_and @1 (bit_not @0)))))
455 /* Convert ~X ^ ~Y to X ^ Y. */
457 (bit_xor (convert1? (bit_not @0)) (convert2? (bit_not @1)))
458 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
459 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
460 (bit_xor (convert @0) (convert @1))))
462 /* Convert ~X ^ C to X ^ ~C. */
464 (bit_xor (convert? (bit_not @0)) INTEGER_CST@1)
465 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
466 (bit_xor (convert @0) (bit_not @1))))
468 /* Fold (X & Y) ^ Y as ~X & Y. */
470 (bit_xor:c (bit_and:c @0 @1) @1)
471 (bit_and (bit_not @0) @1))
473 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
474 operands are another bit-wise operation with a common input. If so,
475 distribute the bit operations to save an operation and possibly two if
476 constants are involved. For example, convert
477 (A | B) & (A | C) into A | (B & C)
478 Further simplification will occur if B and C are constants. */
479 (for op (bit_and bit_ior)
480 rop (bit_ior bit_and)
482 (op (convert? (rop:c @0 @1)) (convert? (rop @0 @2)))
483 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
484 (rop (convert @0) (op (convert @1) (convert @2))))))
494 (abs tree_expr_nonnegative_p@0)
497 /* A few cases of fold-const.c negate_expr_p predicate. */
500 (if ((INTEGRAL_TYPE_P (type)
501 && TYPE_OVERFLOW_WRAPS (type))
502 || (!TYPE_OVERFLOW_SANITIZED (type)
503 && may_negate_without_overflow_p (t)))))
508 (if (!TYPE_OVERFLOW_SANITIZED (type))))
511 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (t)))))
512 /* VECTOR_CST handling of non-wrapping types would recurse in unsupported
516 (if (FLOAT_TYPE_P (TREE_TYPE (type)) || TYPE_OVERFLOW_WRAPS (type))))
518 /* -(A + B) -> (-B) - A. */
520 (negate (plus:c @0 negate_expr_p@1))
521 (if (!HONOR_SIGN_DEPENDENT_ROUNDING (element_mode (type))
522 && !HONOR_SIGNED_ZEROS (element_mode (type)))
523 (minus (negate @1) @0)))
525 /* A - B -> A + (-B) if B is easily negatable. */
527 (minus @0 negate_expr_p@1)
528 (if (!FIXED_POINT_TYPE_P (type))
529 (plus @0 (negate @1))))
531 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
533 For bitwise binary operations apply operand conversions to the
534 binary operation result instead of to the operands. This allows
535 to combine successive conversions and bitwise binary operations.
536 We combine the above two cases by using a conditional convert. */
537 (for bitop (bit_and bit_ior bit_xor)
539 (bitop (convert @0) (convert? @1))
540 (if (((TREE_CODE (@1) == INTEGER_CST
541 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
542 && int_fits_type_p (@1, TREE_TYPE (@0)))
543 || types_match (@0, @1))
544 /* ??? This transform conflicts with fold-const.c doing
545 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
546 constants (if x has signed type, the sign bit cannot be set
547 in c). This folds extension into the BIT_AND_EXPR.
548 Restrict it to GIMPLE to avoid endless recursions. */
549 && (bitop != BIT_AND_EXPR || GIMPLE)
550 && (/* That's a good idea if the conversion widens the operand, thus
551 after hoisting the conversion the operation will be narrower. */
552 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
553 /* It's also a good idea if the conversion is to a non-integer
555 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
556 /* Or if the precision of TO is not the same as the precision
558 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
559 (convert (bitop @0 (convert @1))))))
561 (for bitop (bit_and bit_ior)
562 rbitop (bit_ior bit_and)
563 /* (x | y) & x -> x */
564 /* (x & y) | x -> x */
566 (bitop:c (rbitop:c @0 @1) @0)
568 /* (~x | y) & x -> x & y */
569 /* (~x & y) | x -> x | y */
571 (bitop:c (rbitop:c (bit_not @0) @1) @0)
574 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
575 (for bitop (bit_and bit_ior bit_xor)
577 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
578 (bit_and (bitop @0 @2) @1)))
580 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
582 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
583 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
585 /* Combine successive equal operations with constants. */
586 (for bitop (bit_and bit_ior bit_xor)
588 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
589 (bitop @0 (bitop @1 @2))))
591 /* Try simple folding for X op !X, and X op X with the help
592 of the truth_valued_p and logical_inverted_value predicates. */
593 (match truth_valued_p
595 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
596 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
597 (match truth_valued_p
599 (match truth_valued_p
602 (match (logical_inverted_value @0)
603 (bit_not truth_valued_p@0))
604 (match (logical_inverted_value @0)
605 (eq @0 integer_zerop))
606 (match (logical_inverted_value @0)
607 (ne truth_valued_p@0 integer_truep))
608 (match (logical_inverted_value @0)
609 (bit_xor truth_valued_p@0 integer_truep))
613 (bit_and:c @0 (logical_inverted_value @0))
614 { build_zero_cst (type); })
615 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
616 (for op (bit_ior bit_xor)
618 (op:c truth_valued_p@0 (logical_inverted_value @0))
619 { constant_boolean_node (true, type); }))
621 /* If arg1 and arg2 are booleans (or any single bit type)
622 then try to simplify:
629 But only do this if our result feeds into a comparison as
630 this transformation is not always a win, particularly on
631 targets with and-not instructions.
632 -> simplify_bitwise_binary_boolean */
634 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
635 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
636 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
639 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
640 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
641 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
646 (bit_not (bit_not @0))
649 /* Convert ~ (-A) to A - 1. */
651 (bit_not (convert? (negate @0)))
652 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
653 (convert (minus @0 { build_each_one_cst (TREE_TYPE (@0)); }))))
655 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
657 (bit_not (convert? (minus @0 integer_each_onep)))
658 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
659 (convert (negate @0))))
661 (bit_not (convert? (plus @0 integer_all_onesp)))
662 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
663 (convert (negate @0))))
665 /* Part of convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
667 (bit_not (convert? (bit_xor @0 INTEGER_CST@1)))
668 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
669 (convert (bit_xor @0 (bit_not @1)))))
671 (bit_not (convert? (bit_xor:c (bit_not @0) @1)))
672 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
673 (convert (bit_xor @0 @1))))
675 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
677 (bit_ior:c (bit_and:cs @0 (bit_not @2)) (bit_and:cs @1 @2))
678 (bit_xor (bit_and (bit_xor @0 @1) @2) @0))
680 /* Fold A - (A & B) into ~B & A. */
682 (minus (convert? @0) (convert?:s (bit_and:cs @0 @1)))
683 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
684 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
685 (convert (bit_and (bit_not @1) @0))))
687 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
689 (pointer_plus (pointer_plus:s @0 @1) @3)
690 (pointer_plus @0 (plus @1 @3)))
696 tem4 = (unsigned long) tem3;
701 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
702 /* Conditionally look through a sign-changing conversion. */
703 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
704 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
705 || (GENERIC && type == TREE_TYPE (@1))))
709 tem = (sizetype) ptr;
713 and produce the simpler and easier to analyze with respect to alignment
714 ... = ptr & ~algn; */
716 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
717 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
718 (bit_and @0 { algn; })))
720 /* Try folding difference of addresses. */
722 (minus (convert ADDR_EXPR@0) (convert @1))
723 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
724 (with { HOST_WIDE_INT diff; }
725 (if (ptr_difference_const (@0, @1, &diff))
726 { build_int_cst_type (type, diff); }))))
728 (minus (convert @0) (convert ADDR_EXPR@1))
729 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
730 (with { HOST_WIDE_INT diff; }
731 (if (ptr_difference_const (@0, @1, &diff))
732 { build_int_cst_type (type, diff); }))))
734 /* If arg0 is derived from the address of an object or function, we may
735 be able to fold this expression using the object or function's
738 (bit_and (convert? @0) INTEGER_CST@1)
739 (if (POINTER_TYPE_P (TREE_TYPE (@0))
740 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
744 unsigned HOST_WIDE_INT bitpos;
745 get_pointer_alignment_1 (@0, &align, &bitpos);
747 (if (wi::ltu_p (@1, align / BITS_PER_UNIT))
748 { wide_int_to_tree (type, wi::bit_and (@1, bitpos / BITS_PER_UNIT)); }))))
751 /* We can't reassociate at all for saturating types. */
752 (if (!TYPE_SATURATING (type))
754 /* Contract negates. */
755 /* A + (-B) -> A - B */
757 (plus:c (convert1? @0) (convert2? (negate @1)))
758 /* Apply STRIP_NOPS on @0 and the negate. */
759 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
760 && tree_nop_conversion_p (type, TREE_TYPE (@1))
761 && !TYPE_OVERFLOW_SANITIZED (type))
762 (minus (convert @0) (convert @1))))
763 /* A - (-B) -> A + B */
765 (minus (convert1? @0) (convert2? (negate @1)))
766 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
767 && tree_nop_conversion_p (type, TREE_TYPE (@1))
768 && !TYPE_OVERFLOW_SANITIZED (type))
769 (plus (convert @0) (convert @1))))
772 (negate (convert? (negate @1)))
773 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
774 && !TYPE_OVERFLOW_SANITIZED (type))
777 /* We can't reassociate floating-point unless -fassociative-math
778 or fixed-point plus or minus because of saturation to +-Inf. */
779 (if ((!FLOAT_TYPE_P (type) || flag_associative_math)
780 && !FIXED_POINT_TYPE_P (type))
782 /* Match patterns that allow contracting a plus-minus pair
783 irrespective of overflow issues. */
784 /* (A +- B) - A -> +- B */
785 /* (A +- B) -+ B -> A */
786 /* A - (A +- B) -> -+ B */
787 /* A +- (B -+ A) -> +- B */
789 (minus (plus:c @0 @1) @0)
792 (minus (minus @0 @1) @0)
795 (plus:c (minus @0 @1) @1)
798 (minus @0 (plus:c @0 @1))
801 (minus @0 (minus @0 @1))
804 /* (A +- CST) +- CST -> A + CST */
805 (for outer_op (plus minus)
806 (for inner_op (plus minus)
808 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
809 /* If the constant operation overflows we cannot do the transform
810 as we would introduce undefined overflow, for example
811 with (a - 1) + INT_MIN. */
812 (with { tree cst = fold_binary (outer_op == inner_op
813 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
814 (if (cst && !TREE_OVERFLOW (cst))
815 (inner_op @0 { cst; } ))))))
817 /* (CST - A) +- CST -> CST - A */
818 (for outer_op (plus minus)
820 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
821 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
822 (if (cst && !TREE_OVERFLOW (cst))
823 (minus { cst; } @0)))))
827 (plus:c (bit_not @0) @0)
828 (if (!TYPE_OVERFLOW_TRAPS (type))
829 { build_all_ones_cst (type); }))
833 (plus (convert? (bit_not @0)) integer_each_onep)
834 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
835 (negate (convert @0))))
839 (minus (convert? (negate @0)) integer_each_onep)
840 (if (!TYPE_OVERFLOW_TRAPS (type)
841 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
842 (bit_not (convert @0))))
846 (minus integer_all_onesp @0)
849 /* (T)(P + A) - (T)P -> (T) A */
850 (for add (plus pointer_plus)
852 (minus (convert (add @0 @1))
854 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
855 /* For integer types, if A has a smaller type
856 than T the result depends on the possible
858 E.g. T=size_t, A=(unsigned)429497295, P>0.
859 However, if an overflow in P + A would cause
860 undefined behavior, we can assume that there
862 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
863 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
864 /* For pointer types, if the conversion of A to the
865 final type requires a sign- or zero-extension,
866 then we have to punt - it is not defined which
868 || (POINTER_TYPE_P (TREE_TYPE (@0))
869 && TREE_CODE (@1) == INTEGER_CST
870 && tree_int_cst_sign_bit (@1) == 0))
874 /* Simplifications of MIN_EXPR and MAX_EXPR. */
876 (for minmax (min max)
882 (if (INTEGRAL_TYPE_P (type)
883 && TYPE_MIN_VALUE (type)
884 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
888 (if (INTEGRAL_TYPE_P (type)
889 && TYPE_MAX_VALUE (type)
890 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
894 /* Simplifications of shift and rotates. */
896 (for rotate (lrotate rrotate)
898 (rotate integer_all_onesp@0 @1)
901 /* Optimize -1 >> x for arithmetic right shifts. */
903 (rshift integer_all_onesp@0 @1)
904 (if (!TYPE_UNSIGNED (type)
905 && tree_expr_nonnegative_p (@1))
908 (for shiftrotate (lrotate rrotate lshift rshift)
910 (shiftrotate @0 integer_zerop)
913 (shiftrotate integer_zerop@0 @1)
915 /* Prefer vector1 << scalar to vector1 << vector2
916 if vector2 is uniform. */
917 (for vec (VECTOR_CST CONSTRUCTOR)
919 (shiftrotate @0 vec@1)
920 (with { tree tem = uniform_vector_p (@1); }
922 (shiftrotate @0 { tem; }))))))
924 /* Rewrite an LROTATE_EXPR by a constant into an
925 RROTATE_EXPR by a new constant. */
927 (lrotate @0 INTEGER_CST@1)
928 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
929 build_int_cst (TREE_TYPE (@1),
930 element_precision (type)), @1); }))
932 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
933 (for op (lrotate rrotate rshift lshift)
935 (op (op @0 INTEGER_CST@1) INTEGER_CST@2)
936 (with { unsigned int prec = element_precision (type); }
937 (if (wi::ge_p (@1, 0, TYPE_SIGN (TREE_TYPE (@1)))
938 && wi::lt_p (@1, prec, TYPE_SIGN (TREE_TYPE (@1)))
939 && wi::ge_p (@2, 0, TYPE_SIGN (TREE_TYPE (@2)))
940 && wi::lt_p (@2, prec, TYPE_SIGN (TREE_TYPE (@2))))
941 (with { unsigned int low = wi::add (@1, @2).to_uhwi (); }
942 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
943 being well defined. */
945 (if (op == LROTATE_EXPR || op == RROTATE_EXPR)
946 (op @0 { build_int_cst (TREE_TYPE (@1), low % prec); })
947 (if (TYPE_UNSIGNED (type) || code == LSHIFT_EXPR)
948 { build_zero_cst (type); }
949 (op @0 { build_int_cst (TREE_TYPE (@1), prec - 1); })))
950 (op @0 { build_int_cst (TREE_TYPE (@1), low); })))))))
953 /* ((1 << A) & 1) != 0 -> A == 0
954 ((1 << A) & 1) == 0 -> A != 0 */
958 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
959 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
961 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
962 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
966 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
967 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
969 || (!integer_zerop (@2)
970 && wi::ne_p (wi::lshift (@0, cand), @2)))
971 { constant_boolean_node (cmp == NE_EXPR, type); }
972 (if (!integer_zerop (@2)
973 && wi::eq_p (wi::lshift (@0, cand), @2))
974 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); }))))))
976 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
977 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
978 if the new mask might be further optimized. */
979 (for shift (lshift rshift)
981 (bit_and (convert?:s@4 (shift:s@5 (convert1?@3 @0) INTEGER_CST@1))
983 (if (tree_nop_conversion_p (TREE_TYPE (@4), TREE_TYPE (@5))
984 && TYPE_PRECISION (type) <= HOST_BITS_PER_WIDE_INT
985 && tree_fits_uhwi_p (@1)
986 && tree_to_uhwi (@1) > 0
987 && tree_to_uhwi (@1) < TYPE_PRECISION (type))
990 unsigned int shiftc = tree_to_uhwi (@1);
991 unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (@2);
992 unsigned HOST_WIDE_INT newmask, zerobits = 0;
993 tree shift_type = TREE_TYPE (@3);
996 if (shift == LSHIFT_EXPR)
997 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
998 else if (shift == RSHIFT_EXPR
999 && (TYPE_PRECISION (shift_type)
1000 == GET_MODE_PRECISION (TYPE_MODE (shift_type))))
1002 prec = TYPE_PRECISION (TREE_TYPE (@3));
1004 /* See if more bits can be proven as zero because of
1007 && TYPE_UNSIGNED (TREE_TYPE (@0)))
1009 tree inner_type = TREE_TYPE (@0);
1010 if ((TYPE_PRECISION (inner_type)
1011 == GET_MODE_PRECISION (TYPE_MODE (inner_type)))
1012 && TYPE_PRECISION (inner_type) < prec)
1014 prec = TYPE_PRECISION (inner_type);
1015 /* See if we can shorten the right shift. */
1017 shift_type = inner_type;
1018 /* Otherwise X >> C1 is all zeros, so we'll optimize
1019 it into (X, 0) later on by making sure zerobits
1023 zerobits = ~(unsigned HOST_WIDE_INT) 0;
1026 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
1027 zerobits <<= prec - shiftc;
1029 /* For arithmetic shift if sign bit could be set, zerobits
1030 can contain actually sign bits, so no transformation is
1031 possible, unless MASK masks them all away. In that
1032 case the shift needs to be converted into logical shift. */
1033 if (!TYPE_UNSIGNED (TREE_TYPE (@3))
1034 && prec == TYPE_PRECISION (TREE_TYPE (@3)))
1036 if ((mask & zerobits) == 0)
1037 shift_type = unsigned_type_for (TREE_TYPE (@3));
1043 /* ((X << 16) & 0xff00) is (X, 0). */
1044 (if ((mask & zerobits) == mask)
1045 { build_int_cst (type, 0); }
1046 (with { newmask = mask | zerobits; }
1047 (if (newmask != mask && (newmask & (newmask + 1)) == 0)
1050 /* Only do the transformation if NEWMASK is some integer
1052 for (prec = BITS_PER_UNIT;
1053 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
1054 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
1057 (if (prec < HOST_BITS_PER_WIDE_INT
1058 || newmask == ~(unsigned HOST_WIDE_INT) 0)
1060 { tree newmaskt = build_int_cst_type (TREE_TYPE (@2), newmask); }
1061 (if (!tree_int_cst_equal (newmaskt, @2))
1062 (if (shift_type != TREE_TYPE (@3))
1063 (bit_and (convert (shift:shift_type (convert @3) @1)) { newmaskt; })
1064 (bit_and @4 { newmaskt; })))))))))))))
1066 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
1067 (X & C2) >> C1 into (X >> C1) & (C2 >> C1). */
1068 (for shift (lshift rshift)
1070 (shift (convert?:s (bit_and:s @0 INTEGER_CST@2)) INTEGER_CST@1)
1071 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
1072 (with { tree mask = int_const_binop (shift, fold_convert (type, @2), @1); }
1073 (bit_and (shift (convert @0) @1) { mask; })))))
1076 /* Simplifications of conversions. */
1078 /* Basic strip-useless-type-conversions / strip_nops. */
1079 (for cvt (convert view_convert float fix_trunc)
1082 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
1083 || (GENERIC && type == TREE_TYPE (@0)))
1086 /* Contract view-conversions. */
1088 (view_convert (view_convert @0))
1091 /* For integral conversions with the same precision or pointer
1092 conversions use a NOP_EXPR instead. */
1095 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
1096 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1097 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
1100 /* Strip inner integral conversions that do not change precision or size. */
1102 (view_convert (convert@0 @1))
1103 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1104 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1105 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
1106 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
1109 /* Re-association barriers around constants and other re-association
1110 barriers can be removed. */
1112 (paren CONSTANT_CLASS_P@0)
1115 (paren (paren@1 @0))
1118 /* Handle cases of two conversions in a row. */
1119 (for ocvt (convert float fix_trunc)
1120 (for icvt (convert float)
1125 tree inside_type = TREE_TYPE (@0);
1126 tree inter_type = TREE_TYPE (@1);
1127 int inside_int = INTEGRAL_TYPE_P (inside_type);
1128 int inside_ptr = POINTER_TYPE_P (inside_type);
1129 int inside_float = FLOAT_TYPE_P (inside_type);
1130 int inside_vec = VECTOR_TYPE_P (inside_type);
1131 unsigned int inside_prec = TYPE_PRECISION (inside_type);
1132 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
1133 int inter_int = INTEGRAL_TYPE_P (inter_type);
1134 int inter_ptr = POINTER_TYPE_P (inter_type);
1135 int inter_float = FLOAT_TYPE_P (inter_type);
1136 int inter_vec = VECTOR_TYPE_P (inter_type);
1137 unsigned int inter_prec = TYPE_PRECISION (inter_type);
1138 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
1139 int final_int = INTEGRAL_TYPE_P (type);
1140 int final_ptr = POINTER_TYPE_P (type);
1141 int final_float = FLOAT_TYPE_P (type);
1142 int final_vec = VECTOR_TYPE_P (type);
1143 unsigned int final_prec = TYPE_PRECISION (type);
1144 int final_unsignedp = TYPE_UNSIGNED (type);
1147 /* In addition to the cases of two conversions in a row
1148 handled below, if we are converting something to its own
1149 type via an object of identical or wider precision, neither
1150 conversion is needed. */
1151 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
1153 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
1154 && (((inter_int || inter_ptr) && final_int)
1155 || (inter_float && final_float))
1156 && inter_prec >= final_prec)
1159 /* Likewise, if the intermediate and initial types are either both
1160 float or both integer, we don't need the middle conversion if the
1161 former is wider than the latter and doesn't change the signedness
1162 (for integers). Avoid this if the final type is a pointer since
1163 then we sometimes need the middle conversion. Likewise if the
1164 final type has a precision not equal to the size of its mode. */
1165 (if (((inter_int && inside_int) || (inter_float && inside_float))
1166 && (final_int || final_float)
1167 && inter_prec >= inside_prec
1168 && (inter_float || inter_unsignedp == inside_unsignedp)
1169 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1170 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1173 /* If we have a sign-extension of a zero-extended value, we can
1174 replace that by a single zero-extension. Likewise if the
1175 final conversion does not change precision we can drop the
1176 intermediate conversion. */
1177 (if (inside_int && inter_int && final_int
1178 && ((inside_prec < inter_prec && inter_prec < final_prec
1179 && inside_unsignedp && !inter_unsignedp)
1180 || final_prec == inter_prec))
1183 /* Two conversions in a row are not needed unless:
1184 - some conversion is floating-point (overstrict for now), or
1185 - some conversion is a vector (overstrict for now), or
1186 - the intermediate type is narrower than both initial and
1188 - the intermediate type and innermost type differ in signedness,
1189 and the outermost type is wider than the intermediate, or
1190 - the initial type is a pointer type and the precisions of the
1191 intermediate and final types differ, or
1192 - the final type is a pointer type and the precisions of the
1193 initial and intermediate types differ. */
1194 (if (! inside_float && ! inter_float && ! final_float
1195 && ! inside_vec && ! inter_vec && ! final_vec
1196 && (inter_prec >= inside_prec || inter_prec >= final_prec)
1197 && ! (inside_int && inter_int
1198 && inter_unsignedp != inside_unsignedp
1199 && inter_prec < final_prec)
1200 && ((inter_unsignedp && inter_prec > inside_prec)
1201 == (final_unsignedp && final_prec > inter_prec))
1202 && ! (inside_ptr && inter_prec != final_prec)
1203 && ! (final_ptr && inside_prec != inter_prec)
1204 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1205 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1208 /* A truncation to an unsigned type (a zero-extension) should be
1209 canonicalized as bitwise and of a mask. */
1210 (if (final_int && inter_int && inside_int
1211 && final_prec == inside_prec
1212 && final_prec > inter_prec
1214 (convert (bit_and @0 { wide_int_to_tree
1216 wi::mask (inter_prec, false,
1217 TYPE_PRECISION (inside_type))); })))
1219 /* If we are converting an integer to a floating-point that can
1220 represent it exactly and back to an integer, we can skip the
1221 floating-point conversion. */
1222 (if (GIMPLE /* PR66211 */
1223 && inside_int && inter_float && final_int &&
1224 (unsigned) significand_size (TYPE_MODE (inter_type))
1225 >= inside_prec - !inside_unsignedp)
1228 /* If we have a narrowing conversion to an integral type that is fed by a
1229 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
1230 masks off bits outside the final type (and nothing else). */
1232 (convert (bit_and @0 INTEGER_CST@1))
1233 (if (INTEGRAL_TYPE_P (type)
1234 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1235 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
1236 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
1237 TYPE_PRECISION (type)), 0))
1241 /* (X /[ex] A) * A -> X. */
1243 (mult (convert? (exact_div @0 @1)) @1)
1244 /* Look through a sign-changing conversion. */
1247 /* Canonicalization of binary operations. */
1249 /* Convert X + -C into X - C. */
1251 (plus @0 REAL_CST@1)
1252 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1253 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
1254 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1255 (minus @0 { tem; })))))
1257 /* Convert x+x into x*2.0. */
1260 (if (SCALAR_FLOAT_TYPE_P (type))
1261 (mult @0 { build_real (type, dconst2); })))
1264 (minus integer_zerop @1)
1267 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
1268 ARG0 is zero and X + ARG0 reduces to X, since that would mean
1269 (-ARG1 + ARG0) reduces to -ARG1. */
1271 (minus real_zerop@0 @1)
1272 (if (fold_real_zero_addition_p (type, @0, 0))
1275 /* Transform x * -1 into -x. */
1277 (mult @0 integer_minus_onep)
1280 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
1282 (complex (realpart @0) (imagpart @0))
1285 (realpart (complex @0 @1))
1288 (imagpart (complex @0 @1))
1292 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
1293 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
1298 (bswap (bit_not (bswap @0)))
1300 (for bitop (bit_xor bit_ior bit_and)
1302 (bswap (bitop:c (bswap @0) @1))
1303 (bitop @0 (bswap @1)))))
1306 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
1308 /* Simplify constant conditions.
1309 Only optimize constant conditions when the selected branch
1310 has the same type as the COND_EXPR. This avoids optimizing
1311 away "c ? x : throw", where the throw has a void type.
1312 Note that we cannot throw away the fold-const.c variant nor
1313 this one as we depend on doing this transform before possibly
1314 A ? B : B -> B triggers and the fold-const.c one can optimize
1315 0 ? A : B to B even if A has side-effects. Something
1316 genmatch cannot handle. */
1318 (cond INTEGER_CST@0 @1 @2)
1319 (if (integer_zerop (@0))
1320 (if (!VOID_TYPE_P (TREE_TYPE (@2)) || VOID_TYPE_P (type))
1322 (if (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))
1325 (vec_cond VECTOR_CST@0 @1 @2)
1326 (if (integer_all_onesp (@0))
1328 (if (integer_zerop (@0))
1331 (for cnd (cond vec_cond)
1332 /* A ? B : (A ? X : C) -> A ? B : C. */
1334 (cnd @0 (cnd @0 @1 @2) @3)
1337 (cnd @0 @1 (cnd @0 @2 @3))
1340 /* A ? B : B -> B. */
1345 /* !A ? B : C -> A ? C : B. */
1347 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
1350 /* A + (B vcmp C ? 1 : 0) -> A - (B vcmp C), since vector comparisons
1351 return all-1 or all-0 results. */
1352 /* ??? We could instead convert all instances of the vec_cond to negate,
1353 but that isn't necessarily a win on its own. */
1355 (plus:c @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1356 (if (VECTOR_TYPE_P (type)
1357 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1358 && (TYPE_MODE (TREE_TYPE (type))
1359 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1360 (minus @3 (view_convert @0))))
1362 /* ... likewise A - (B vcmp C ? 1 : 0) -> A + (B vcmp C). */
1364 (minus @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1365 (if (VECTOR_TYPE_P (type)
1366 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1367 && (TYPE_MODE (TREE_TYPE (type))
1368 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1369 (plus @3 (view_convert @0))))
1372 /* Simplifications of comparisons. */
1374 /* See if we can reduce the magnitude of a constant involved in a
1375 comparison by changing the comparison code. This is a canonicalization
1376 formerly done by maybe_canonicalize_comparison_1. */
1380 (cmp @0 INTEGER_CST@1)
1381 (if (tree_int_cst_sgn (@1) == -1)
1382 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1386 (cmp @0 INTEGER_CST@1)
1387 (if (tree_int_cst_sgn (@1) == 1)
1388 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1391 /* We can simplify a logical negation of a comparison to the
1392 inverted comparison. As we cannot compute an expression
1393 operator using invert_tree_comparison we have to simulate
1394 that with expression code iteration. */
1395 (for cmp (tcc_comparison)
1396 icmp (inverted_tcc_comparison)
1397 ncmp (inverted_tcc_comparison_with_nans)
1398 /* Ideally we'd like to combine the following two patterns
1399 and handle some more cases by using
1400 (logical_inverted_value (cmp @0 @1))
1401 here but for that genmatch would need to "inline" that.
1402 For now implement what forward_propagate_comparison did. */
1404 (bit_not (cmp @0 @1))
1405 (if (VECTOR_TYPE_P (type)
1406 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
1407 /* Comparison inversion may be impossible for trapping math,
1408 invert_tree_comparison will tell us. But we can't use
1409 a computed operator in the replacement tree thus we have
1410 to play the trick below. */
1411 (with { enum tree_code ic = invert_tree_comparison
1412 (cmp, HONOR_NANS (@0)); }
1418 (bit_xor (cmp @0 @1) integer_truep)
1419 (with { enum tree_code ic = invert_tree_comparison
1420 (cmp, HONOR_NANS (@0)); }
1426 /* Transform comparisons of the form X - Y CMP 0 to X CMP Y.
1427 ??? The transformation is valid for the other operators if overflow
1428 is undefined for the type, but performing it here badly interacts
1429 with the transformation in fold_cond_expr_with_comparison which
1430 attempts to synthetize ABS_EXPR. */
1433 (cmp (minus@2 @0 @1) integer_zerop)
1434 (if (single_use (@2))
1437 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
1438 signed arithmetic case. That form is created by the compiler
1439 often enough for folding it to be of value. One example is in
1440 computing loop trip counts after Operator Strength Reduction. */
1441 (for cmp (simple_comparison)
1442 scmp (swapped_simple_comparison)
1444 (cmp (mult @0 INTEGER_CST@1) integer_zerop@2)
1445 /* Handle unfolded multiplication by zero. */
1446 (if (integer_zerop (@1))
1448 (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1449 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
1450 /* If @1 is negative we swap the sense of the comparison. */
1451 (if (tree_int_cst_sgn (@1) < 0)
1455 /* Simplify comparison of something with itself. For IEEE
1456 floating-point, we can only do some of these simplifications. */
1459 (if (! FLOAT_TYPE_P (TREE_TYPE (@0))
1460 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1461 { constant_boolean_node (true, type); }))
1470 || ! FLOAT_TYPE_P (TREE_TYPE (@0))
1471 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1472 { constant_boolean_node (false, type); })))
1474 /* Fold ~X op ~Y as Y op X. */
1475 (for cmp (simple_comparison)
1477 (cmp (bit_not @0) (bit_not @1))
1480 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
1481 (for cmp (simple_comparison)
1482 scmp (swapped_simple_comparison)
1484 (cmp (bit_not @0) CONSTANT_CLASS_P@1)
1485 (if (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST)
1486 (scmp @0 (bit_not @1)))))
1488 (for cmp (simple_comparison)
1489 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
1491 (cmp (convert@2 @0) (convert? @1))
1492 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1493 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1494 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@0)))
1495 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1496 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@1))))
1499 tree type1 = TREE_TYPE (@1);
1500 if (TREE_CODE (@1) == REAL_CST && !DECIMAL_FLOAT_TYPE_P (type1))
1502 REAL_VALUE_TYPE orig = TREE_REAL_CST (@1);
1503 if (TYPE_PRECISION (type1) > TYPE_PRECISION (float_type_node)
1504 && exact_real_truncate (TYPE_MODE (float_type_node), &orig))
1505 type1 = float_type_node;
1506 if (TYPE_PRECISION (type1) > TYPE_PRECISION (double_type_node)
1507 && exact_real_truncate (TYPE_MODE (double_type_node), &orig))
1508 type1 = double_type_node;
1511 = (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (type1)
1512 ? TREE_TYPE (@0) : type1);
1514 (if (TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (newtype))
1515 (cmp (convert:newtype @0) (convert:newtype @1))))))
1519 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
1521 /* a CMP (-0) -> a CMP 0 */
1522 (if (REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (@1)))
1523 (cmp @0 { build_real (TREE_TYPE (@1), dconst0); }))
1524 /* x != NaN is always true, other ops are always false. */
1525 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1526 && ! HONOR_SNANS (@1))
1527 { constant_boolean_node (cmp == NE_EXPR, type); })
1528 /* Fold comparisons against infinity. */
1529 (if (REAL_VALUE_ISINF (TREE_REAL_CST (@1))
1530 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (@1))))
1533 REAL_VALUE_TYPE max;
1534 enum tree_code code = cmp;
1535 bool neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1));
1537 code = swap_tree_comparison (code);
1540 /* x > +Inf is always false, if with ignore sNANs. */
1541 (if (code == GT_EXPR
1542 && ! HONOR_SNANS (@0))
1543 { constant_boolean_node (false, type); })
1544 (if (code == LE_EXPR)
1545 /* x <= +Inf is always true, if we don't case about NaNs. */
1546 (if (! HONOR_NANS (@0))
1547 { constant_boolean_node (true, type); }
1548 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
1550 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
1551 (if (code == EQ_EXPR || code == GE_EXPR)
1552 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1554 (lt @0 { build_real (TREE_TYPE (@0), max); })
1555 (gt @0 { build_real (TREE_TYPE (@0), max); }))))
1556 /* x < +Inf is always equal to x <= DBL_MAX. */
1557 (if (code == LT_EXPR)
1558 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1560 (ge @0 { build_real (TREE_TYPE (@0), max); })
1561 (le @0 { build_real (TREE_TYPE (@0), max); }))))
1562 /* x != +Inf is always equal to !(x > DBL_MAX). */
1563 (if (code == NE_EXPR)
1564 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1565 (if (! HONOR_NANS (@0))
1567 (ge @0 { build_real (TREE_TYPE (@0), max); })
1568 (le @0 { build_real (TREE_TYPE (@0), max); }))
1570 (bit_xor (lt @0 { build_real (TREE_TYPE (@0), max); })
1571 { build_one_cst (type); })
1572 (bit_xor (gt @0 { build_real (TREE_TYPE (@0), max); })
1573 { build_one_cst (type); }))))))))))
1575 /* If this is a comparison of a real constant with a PLUS_EXPR
1576 or a MINUS_EXPR of a real constant, we can convert it into a
1577 comparison with a revised real constant as long as no overflow
1578 occurs when unsafe_math_optimizations are enabled. */
1579 (if (flag_unsafe_math_optimizations)
1580 (for op (plus minus)
1582 (cmp (op @0 REAL_CST@1) REAL_CST@2)
1585 tree tem = const_binop (op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR,
1586 TREE_TYPE (@1), @2, @1);
1588 (if (!TREE_OVERFLOW (tem))
1589 (cmp @0 { tem; }))))))
1591 /* Likewise, we can simplify a comparison of a real constant with
1592 a MINUS_EXPR whose first operand is also a real constant, i.e.
1593 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
1594 floating-point types only if -fassociative-math is set. */
1595 (if (flag_associative_math)
1597 (cmp (minus REAL_CST@0 @1) REAL_CST@2)
1598 (with { tree tem = const_binop (MINUS_EXPR, TREE_TYPE (@1), @0, @2); }
1599 (if (!TREE_OVERFLOW (tem))
1600 (cmp { tem; } @1)))))
1602 /* Fold comparisons against built-in math functions. */
1603 (if (flag_unsafe_math_optimizations
1604 && ! flag_errno_math)
1607 (cmp (sq @0) REAL_CST@1)
1609 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1611 /* sqrt(x) < y is always false, if y is negative. */
1612 (if (cmp == EQ_EXPR || cmp == LT_EXPR || cmp == LE_EXPR)
1613 { constant_boolean_node (false, type); })
1614 /* sqrt(x) > y is always true, if y is negative and we
1615 don't care about NaNs, i.e. negative values of x. */
1616 (if (cmp == NE_EXPR || !HONOR_NANS (@0))
1617 { constant_boolean_node (true, type); })
1618 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
1619 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })))
1620 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1624 REAL_ARITHMETIC (c2, MULT_EXPR,
1625 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1626 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1628 (if (REAL_VALUE_ISINF (c2))
1629 /* sqrt(x) > y is x == +Inf, when y is very large. */
1630 (if (HONOR_INFINITIES (@0))
1631 (eq @0 { build_real (TREE_TYPE (@0), c2); })
1632 { constant_boolean_node (false, type); })
1633 /* sqrt(x) > c is the same as x > c*c. */
1634 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))
1635 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1639 REAL_ARITHMETIC (c2, MULT_EXPR,
1640 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1641 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1643 (if (REAL_VALUE_ISINF (c2))
1645 /* sqrt(x) < y is always true, when y is a very large
1646 value and we don't care about NaNs or Infinities. */
1647 (if (! HONOR_NANS (@0) && ! HONOR_INFINITIES (@0))
1648 { constant_boolean_node (true, type); })
1649 /* sqrt(x) < y is x != +Inf when y is very large and we
1650 don't care about NaNs. */
1651 (if (! HONOR_NANS (@0))
1652 (ne @0 { build_real (TREE_TYPE (@0), c2); }))
1653 /* sqrt(x) < y is x >= 0 when y is very large and we
1654 don't care about Infinities. */
1655 (if (! HONOR_INFINITIES (@0))
1656 (ge @0 { build_real (TREE_TYPE (@0), dconst0); }))
1657 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
1660 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1661 (ne @0 { build_real (TREE_TYPE (@0), c2); }))))
1662 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
1663 (if (! HONOR_NANS (@0))
1664 (cmp @0 { build_real (TREE_TYPE (@0), c2); })
1665 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
1668 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1669 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))))))))))
1671 /* Unordered tests if either argument is a NaN. */
1673 (bit_ior (unordered @0 @0) (unordered @1 @1))
1674 (if (types_match (@0, @1))
1677 (bit_and (ordered @0 @0) (ordered @1 @1))
1678 (if (types_match (@0, @1))
1681 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1684 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1687 /* -A CMP -B -> B CMP A. */
1688 (for cmp (tcc_comparison)
1689 scmp (swapped_tcc_comparison)
1691 (cmp (negate @0) (negate @1))
1692 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1693 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1694 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1697 (cmp (negate @0) CONSTANT_CLASS_P@1)
1698 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1699 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1700 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1701 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1702 (if (tem && !TREE_OVERFLOW (tem))
1703 (scmp @0 { tem; }))))))
1705 /* From fold_sign_changed_comparison and fold_widened_comparison. */
1706 (for cmp (simple_comparison)
1708 (cmp (convert@0 @00) (convert?@1 @10))
1709 (if (TREE_CODE (TREE_TYPE (@0)) == INTEGER_TYPE
1710 /* Disable this optimization if we're casting a function pointer
1711 type on targets that require function pointer canonicalization. */
1712 && !(targetm.have_canonicalize_funcptr_for_compare ()
1713 && TREE_CODE (TREE_TYPE (@00)) == POINTER_TYPE
1714 && TREE_CODE (TREE_TYPE (TREE_TYPE (@00))) == FUNCTION_TYPE)
1716 (if (TYPE_PRECISION (TREE_TYPE (@00)) == TYPE_PRECISION (TREE_TYPE (@0))
1717 && (TREE_CODE (@10) == INTEGER_CST
1718 || (@1 != @10 && types_match (TREE_TYPE (@10), TREE_TYPE (@00))))
1719 && (TYPE_UNSIGNED (TREE_TYPE (@00)) == TYPE_UNSIGNED (TREE_TYPE (@0))
1722 && (POINTER_TYPE_P (TREE_TYPE (@00)) == POINTER_TYPE_P (TREE_TYPE (@0))))
1723 /* ??? The special-casing of INTEGER_CST conversion was in the original
1724 code and here to avoid a spurious overflow flag on the resulting
1725 constant which fold_convert produces. */
1726 (if (TREE_CODE (@1) == INTEGER_CST)
1727 (cmp @00 { force_fit_type (TREE_TYPE (@00), wi::to_widest (@1), 0,
1728 TREE_OVERFLOW (@1)); })
1729 (cmp @00 (convert @1)))
1731 (if (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (TREE_TYPE (@00)))
1732 /* If possible, express the comparison in the shorter mode. */
1733 (if ((cmp == EQ_EXPR || cmp == NE_EXPR
1734 || TYPE_UNSIGNED (TREE_TYPE (@0)) == TYPE_UNSIGNED (TREE_TYPE (@00)))
1735 && (types_match (TREE_TYPE (@10), TREE_TYPE (@00))
1736 || ((TYPE_PRECISION (TREE_TYPE (@00))
1737 >= TYPE_PRECISION (TREE_TYPE (@10)))
1738 && (TYPE_UNSIGNED (TREE_TYPE (@00))
1739 == TYPE_UNSIGNED (TREE_TYPE (@10))))
1740 || (TREE_CODE (@10) == INTEGER_CST
1741 && (TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1742 || TREE_CODE (TREE_TYPE (@00)) == BOOLEAN_TYPE)
1743 && int_fits_type_p (@10, TREE_TYPE (@00)))))
1744 (cmp @00 (convert @10))
1745 (if (TREE_CODE (@10) == INTEGER_CST
1746 && TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1747 && !int_fits_type_p (@10, TREE_TYPE (@00)))
1750 tree min = lower_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1751 tree max = upper_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1752 bool above = integer_nonzerop (const_binop (LT_EXPR, type, max, @10));
1753 bool below = integer_nonzerop (const_binop (LT_EXPR, type, @10, min));
1755 (if (above || below)
1756 (if (cmp == EQ_EXPR || cmp == NE_EXPR)
1757 { constant_boolean_node (cmp == EQ_EXPR ? false : true, type); }
1758 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1759 { constant_boolean_node (above ? true : false, type); }
1760 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1761 { constant_boolean_node (above ? false : true, type); }))))))))))))
1764 /* A local variable can never be pointed to by
1765 the default SSA name of an incoming parameter.
1766 SSA names are canonicalized to 2nd place. */
1768 (cmp addr@0 SSA_NAME@1)
1769 (if (SSA_NAME_IS_DEFAULT_DEF (@1)
1770 && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL)
1771 (with { tree base = get_base_address (TREE_OPERAND (@0, 0)); }
1772 (if (TREE_CODE (base) == VAR_DECL
1773 && auto_var_in_fn_p (base, current_function_decl))
1774 (if (cmp == NE_EXPR)
1775 { constant_boolean_node (true, type); }
1776 { constant_boolean_node (false, type); }))))))
1778 /* Equality compare simplifications from fold_binary */
1781 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
1782 Similarly for NE_EXPR. */
1784 (cmp (convert?@3 (bit_ior @0 INTEGER_CST@1)) INTEGER_CST@2)
1785 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0))
1786 && wi::bit_and_not (@1, @2) != 0)
1787 { constant_boolean_node (cmp == NE_EXPR, type); }))
1789 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
1791 (cmp (bit_xor @0 @1) integer_zerop)
1794 /* (X ^ Y) == Y becomes X == 0.
1795 Likewise (X ^ Y) == X becomes Y == 0. */
1797 (cmp:c (bit_xor:c @0 @1) @0)
1798 (cmp @1 { build_zero_cst (TREE_TYPE (@1)); }))
1800 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
1802 (cmp (convert?@3 (bit_xor @0 INTEGER_CST@1)) INTEGER_CST@2)
1803 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0)))
1804 (cmp @0 (bit_xor @1 (convert @2)))))
1806 /* If this is an equality comparison of the address of two non-weak,
1807 unaliased symbols neither of which are extern (since we do not
1808 have access to attributes for externs), then we know the result. */
1810 (cmp (convert? addr@0) (convert? addr@1))
1811 (if (decl_in_symtab_p (TREE_OPERAND (@0, 0))
1812 && decl_in_symtab_p (TREE_OPERAND (@1, 0)))
1815 int equal = symtab_node::get_create (TREE_OPERAND (@0, 0))
1816 ->equal_address_to (symtab_node::get_create (TREE_OPERAND (@1, 0)));
1819 { constant_boolean_node (equal ? cmp == EQ_EXPR : cmp != EQ_EXPR, type); }))))
1822 (cmp (convert? addr@0) integer_zerop)
1823 (if (tree_single_nonzero_warnv_p (@0, NULL))
1824 { constant_boolean_node (cmp == NE_EXPR, type); })))
1827 /* Non-equality compare simplifications from fold_binary */
1828 (for cmp (lt gt le ge)
1829 /* Comparisons with the highest or lowest possible integer of
1830 the specified precision will have known values. */
1832 (cmp (convert?@2 @0) INTEGER_CST@1)
1833 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1834 && tree_nop_conversion_p (TREE_TYPE (@2), TREE_TYPE (@0)))
1837 tree arg1_type = TREE_TYPE (@1);
1838 unsigned int prec = TYPE_PRECISION (arg1_type);
1839 wide_int max = wi::max_value (arg1_type);
1840 wide_int signed_max = wi::max_value (prec, SIGNED);
1841 wide_int min = wi::min_value (arg1_type);
1844 (if (wi::eq_p (@1, max))
1846 (if (cmp == GT_EXPR)
1847 { constant_boolean_node (false, type); })
1848 (if (cmp == GE_EXPR)
1850 (if (cmp == LE_EXPR)
1851 { constant_boolean_node (true, type); })
1852 (if (cmp == LT_EXPR)
1854 (if (wi::eq_p (@1, max - 1))
1856 (if (cmp == GT_EXPR)
1857 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))
1858 (if (cmp == LE_EXPR)
1859 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1860 (if (wi::eq_p (@1, min))
1862 (if (cmp == LT_EXPR)
1863 { constant_boolean_node (false, type); })
1864 (if (cmp == LE_EXPR)
1866 (if (cmp == GE_EXPR)
1867 { constant_boolean_node (true, type); })
1868 (if (cmp == GT_EXPR)
1870 (if (wi::eq_p (@1, min + 1))
1872 (if (cmp == GE_EXPR)
1873 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))
1874 (if (cmp == LT_EXPR)
1875 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1876 (if (wi::eq_p (@1, signed_max)
1877 && TYPE_UNSIGNED (arg1_type)
1878 /* We will flip the signedness of the comparison operator
1879 associated with the mode of @1, so the sign bit is
1880 specified by this mode. Check that @1 is the signed
1881 max associated with this sign bit. */
1882 && prec == GET_MODE_PRECISION (TYPE_MODE (arg1_type))
1883 /* signed_type does not work on pointer types. */
1884 && INTEGRAL_TYPE_P (arg1_type))
1885 /* The following case also applies to X < signed_max+1
1886 and X >= signed_max+1 because previous transformations. */
1887 (if (cmp == LE_EXPR || cmp == GT_EXPR)
1888 (with { tree st = signed_type_for (arg1_type); }
1889 (if (cmp == LE_EXPR)
1890 (ge (convert:st @0) { build_zero_cst (st); })
1891 (lt (convert:st @0) { build_zero_cst (st); }))))))))))
1894 /* bool_var != 0 becomes bool_var. */
1896 (ne @0 integer_zerop@1)
1897 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1898 && types_match (type, TREE_TYPE (@0)))
1900 /* bool_var == 1 becomes bool_var. */
1902 (eq @0 integer_onep@1)
1903 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1904 && types_match (type, TREE_TYPE (@0)))
1908 /* Simplification of math builtins. */
1910 /* fold_builtin_logarithm */
1911 (if (flag_unsafe_math_optimizations)
1912 /* Special case, optimize logN(expN(x)) = x. */
1913 (for logs (LOG LOG2 LOG10)
1914 exps (EXP EXP2 EXP10)
1918 /* Optimize logN(func()) for various exponential functions. We
1919 want to determine the value "x" and the power "exponent" in
1920 order to transform logN(x**exponent) into exponent*logN(x). */
1921 (for logs (LOG LOG LOG LOG
1923 LOG10 LOG10 LOG10 LOG10)
1924 exps (EXP EXP2 EXP10 POW10)
1931 CASE_FLT_FN (BUILT_IN_EXP):
1932 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
1933 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1936 CASE_FLT_FN (BUILT_IN_EXP2):
1937 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
1938 x = build_real (type, dconst2);
1940 CASE_FLT_FN (BUILT_IN_EXP10):
1941 CASE_FLT_FN (BUILT_IN_POW10):
1942 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
1944 REAL_VALUE_TYPE dconst10;
1945 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
1946 x = build_real (type, dconst10);
1951 (mult (logs { x; }) @0))))
1962 CASE_FLT_FN (BUILT_IN_SQRT):
1963 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
1964 x = build_real (type, dconsthalf);
1966 CASE_FLT_FN (BUILT_IN_CBRT):
1967 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
1968 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1973 (mult { x; } (logs @0)))))
1974 /* logN(pow(x,exponent) -> exponent*logN(x). */
1975 (for logs (LOG LOG2 LOG10)
1979 (mult @1 (logs @0)))))
1981 /* Narrowing of arithmetic and logical operations.
1983 These are conceptually similar to the transformations performed for
1984 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
1985 term we want to move all that code out of the front-ends into here. */
1987 /* If we have a narrowing conversion of an arithmetic operation where
1988 both operands are widening conversions from the same type as the outer
1989 narrowing conversion. Then convert the innermost operands to a suitable
1990 unsigned type (to avoid introducing undefined behaviour), perform the
1991 operation and convert the result to the desired type. */
1992 (for op (plus minus)
1994 (convert (op:s (convert@2 @0) (convert@3 @1)))
1995 (if (INTEGRAL_TYPE_P (type)
1996 /* We check for type compatibility between @0 and @1 below,
1997 so there's no need to check that @1/@3 are integral types. */
1998 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1999 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2000 /* The precision of the type of each operand must match the
2001 precision of the mode of each operand, similarly for the
2003 && (TYPE_PRECISION (TREE_TYPE (@0))
2004 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2005 && (TYPE_PRECISION (TREE_TYPE (@1))
2006 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2007 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2008 /* The inner conversion must be a widening conversion. */
2009 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2010 && types_match (@0, @1)
2011 && types_match (@0, type))
2012 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2013 (convert (op @0 @1))
2014 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2015 (convert (op (convert:utype @0) (convert:utype @1))))))))
2017 /* This is another case of narrowing, specifically when there's an outer
2018 BIT_AND_EXPR which masks off bits outside the type of the innermost
2019 operands. Like the previous case we have to convert the operands
2020 to unsigned types to avoid introducing undefined behaviour for the
2021 arithmetic operation. */
2022 (for op (minus plus)
2024 (bit_and (op:s (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
2025 (if (INTEGRAL_TYPE_P (type)
2026 /* We check for type compatibility between @0 and @1 below,
2027 so there's no need to check that @1/@3 are integral types. */
2028 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2029 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2030 /* The precision of the type of each operand must match the
2031 precision of the mode of each operand, similarly for the
2033 && (TYPE_PRECISION (TREE_TYPE (@0))
2034 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2035 && (TYPE_PRECISION (TREE_TYPE (@1))
2036 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2037 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2038 /* The inner conversion must be a widening conversion. */
2039 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2040 && types_match (@0, @1)
2041 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
2042 <= TYPE_PRECISION (TREE_TYPE (@0)))
2043 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
2044 || tree_int_cst_sgn (@4) >= 0))
2045 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2046 (with { tree ntype = TREE_TYPE (@0); }
2047 (convert (bit_and (op @0 @1) (convert:ntype @4))))
2048 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2049 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
2050 (convert:utype @4))))))))