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[gcc.git] / gcc / match.pd
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.
4
5 Copyright (C) 2014-2015 Free Software Foundation, Inc.
6 Contributed by Richard Biener <rguenther@suse.de>
7 and Prathamesh Kulkarni <bilbotheelffriend@gmail.com>
8
9 This file is part of GCC.
10
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
14 version.
15
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
19 for more details.
20
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/>. */
24
25
26 /* Generic tree predicates we inherit. */
27 (define_predicates
28 integer_onep integer_zerop integer_all_onesp integer_minus_onep
29 integer_each_onep integer_truep integer_nonzerop
30 real_zerop real_onep real_minus_onep
31 zerop
32 CONSTANT_CLASS_P
33 tree_expr_nonnegative_p
34 integer_pow2p
35 HONOR_NANS)
36
37 /* Operator lists. */
38 (define_operator_list tcc_comparison
39 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
40 (define_operator_list inverted_tcc_comparison
41 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
42 (define_operator_list inverted_tcc_comparison_with_nans
43 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
44 (define_operator_list swapped_tcc_comparison
45 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
46 (define_operator_list simple_comparison lt le eq ne ge gt)
47 (define_operator_list swapped_simple_comparison gt ge eq ne le lt)
48
49 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
50 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
51 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
52 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
53 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
54 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
55 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
56 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
57 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
58 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
59 (define_operator_list SIN BUILT_IN_SINF BUILT_IN_SIN BUILT_IN_SINL)
60 (define_operator_list COS BUILT_IN_COSF BUILT_IN_COS BUILT_IN_COSL)
61 (define_operator_list TAN BUILT_IN_TANF BUILT_IN_TAN BUILT_IN_TANL)
62 (define_operator_list COSH BUILT_IN_COSHF BUILT_IN_COSH BUILT_IN_COSHL)
63 (define_operator_list CEXPI BUILT_IN_CEXPIF BUILT_IN_CEXPI BUILT_IN_CEXPIL)
64
65 /* Simplifications of operations with one constant operand and
66 simplifications to constants or single values. */
67
68 (for op (plus pointer_plus minus bit_ior bit_xor)
69 (simplify
70 (op @0 integer_zerop)
71 (non_lvalue @0)))
72
73 /* 0 +p index -> (type)index */
74 (simplify
75 (pointer_plus integer_zerop @1)
76 (non_lvalue (convert @1)))
77
78 /* See if ARG1 is zero and X + ARG1 reduces to X.
79 Likewise if the operands are reversed. */
80 (simplify
81 (plus:c @0 real_zerop@1)
82 (if (fold_real_zero_addition_p (type, @1, 0))
83 (non_lvalue @0)))
84
85 /* See if ARG1 is zero and X - ARG1 reduces to X. */
86 (simplify
87 (minus @0 real_zerop@1)
88 (if (fold_real_zero_addition_p (type, @1, 1))
89 (non_lvalue @0)))
90
91 /* Simplify x - x.
92 This is unsafe for certain floats even in non-IEEE formats.
93 In IEEE, it is unsafe because it does wrong for NaNs.
94 Also note that operand_equal_p is always false if an operand
95 is volatile. */
96 (simplify
97 (minus @0 @0)
98 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
99 { build_zero_cst (type); }))
100
101 (simplify
102 (mult @0 integer_zerop@1)
103 @1)
104
105 /* Maybe fold x * 0 to 0. The expressions aren't the same
106 when x is NaN, since x * 0 is also NaN. Nor are they the
107 same in modes with signed zeros, since multiplying a
108 negative value by 0 gives -0, not +0. */
109 (simplify
110 (mult @0 real_zerop@1)
111 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
112 @1))
113
114 /* In IEEE floating point, x*1 is not equivalent to x for snans.
115 Likewise for complex arithmetic with signed zeros. */
116 (simplify
117 (mult @0 real_onep)
118 (if (!HONOR_SNANS (type)
119 && (!HONOR_SIGNED_ZEROS (type)
120 || !COMPLEX_FLOAT_TYPE_P (type)))
121 (non_lvalue @0)))
122
123 /* Transform x * -1.0 into -x. */
124 (simplify
125 (mult @0 real_minus_onep)
126 (if (!HONOR_SNANS (type)
127 && (!HONOR_SIGNED_ZEROS (type)
128 || !COMPLEX_FLOAT_TYPE_P (type)))
129 (negate @0)))
130
131 /* Make sure to preserve divisions by zero. This is the reason why
132 we don't simplify x / x to 1 or 0 / x to 0. */
133 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
134 (simplify
135 (op @0 integer_onep)
136 (non_lvalue @0)))
137
138 /* X / -1 is -X. */
139 (for div (trunc_div ceil_div floor_div round_div exact_div)
140 (simplify
141 (div @0 integer_minus_onep@1)
142 (if (!TYPE_UNSIGNED (type))
143 (negate @0))))
144
145 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
146 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
147 (simplify
148 (floor_div @0 @1)
149 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
150 && TYPE_UNSIGNED (type))
151 (trunc_div @0 @1)))
152
153 /* Combine two successive divisions. Note that combining ceil_div
154 and floor_div is trickier and combining round_div even more so. */
155 (for div (trunc_div exact_div)
156 (simplify
157 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
158 (with {
159 bool overflow_p;
160 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
161 }
162 (if (!overflow_p)
163 (div @0 { wide_int_to_tree (type, mul); })
164 (if (TYPE_UNSIGNED (type)
165 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED))
166 { build_zero_cst (type); })))))
167
168 /* Optimize A / A to 1.0 if we don't care about
169 NaNs or Infinities. */
170 (simplify
171 (rdiv @0 @0)
172 (if (FLOAT_TYPE_P (type)
173 && ! HONOR_NANS (type)
174 && ! HONOR_INFINITIES (type))
175 { build_one_cst (type); }))
176
177 /* Optimize -A / A to -1.0 if we don't care about
178 NaNs or Infinities. */
179 (simplify
180 (rdiv:c @0 (negate @0))
181 (if (FLOAT_TYPE_P (type)
182 && ! HONOR_NANS (type)
183 && ! HONOR_INFINITIES (type))
184 { build_minus_one_cst (type); }))
185
186 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
187 (simplify
188 (rdiv @0 real_onep)
189 (if (!HONOR_SNANS (type))
190 (non_lvalue @0)))
191
192 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
193 (simplify
194 (rdiv @0 real_minus_onep)
195 (if (!HONOR_SNANS (type))
196 (negate @0)))
197
198 /* If ARG1 is a constant, we can convert this to a multiply by the
199 reciprocal. This does not have the same rounding properties,
200 so only do this if -freciprocal-math. We can actually
201 always safely do it if ARG1 is a power of two, but it's hard to
202 tell if it is or not in a portable manner. */
203 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
204 (simplify
205 (rdiv @0 cst@1)
206 (if (optimize)
207 (if (flag_reciprocal_math
208 && !real_zerop (@1))
209 (with
210 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
211 (if (tem)
212 (mult @0 { tem; } )))
213 (if (cst != COMPLEX_CST)
214 (with { tree inverse = exact_inverse (type, @1); }
215 (if (inverse)
216 (mult @0 { inverse; } ))))))))
217
218 /* Same applies to modulo operations, but fold is inconsistent here
219 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
220 (for mod (ceil_mod floor_mod round_mod trunc_mod)
221 /* 0 % X is always zero. */
222 (simplify
223 (mod integer_zerop@0 @1)
224 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
225 (if (!integer_zerop (@1))
226 @0))
227 /* X % 1 is always zero. */
228 (simplify
229 (mod @0 integer_onep)
230 { build_zero_cst (type); })
231 /* X % -1 is zero. */
232 (simplify
233 (mod @0 integer_minus_onep@1)
234 (if (!TYPE_UNSIGNED (type))
235 { build_zero_cst (type); }))
236 /* (X % Y) % Y is just X % Y. */
237 (simplify
238 (mod (mod@2 @0 @1) @1)
239 @2)
240 /* From extract_muldiv_1: (X * C1) % C2 is zero if C1 is a multiple of C2. */
241 (simplify
242 (mod (mult @0 INTEGER_CST@1) INTEGER_CST@2)
243 (if (ANY_INTEGRAL_TYPE_P (type)
244 && TYPE_OVERFLOW_UNDEFINED (type)
245 && wi::multiple_of_p (@1, @2, TYPE_SIGN (type)))
246 { build_zero_cst (type); })))
247
248 /* X % -C is the same as X % C. */
249 (simplify
250 (trunc_mod @0 INTEGER_CST@1)
251 (if (TYPE_SIGN (type) == SIGNED
252 && !TREE_OVERFLOW (@1)
253 && wi::neg_p (@1)
254 && !TYPE_OVERFLOW_TRAPS (type)
255 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
256 && !sign_bit_p (@1, @1))
257 (trunc_mod @0 (negate @1))))
258
259 /* X % -Y is the same as X % Y. */
260 (simplify
261 (trunc_mod @0 (convert? (negate @1)))
262 (if (!TYPE_UNSIGNED (type)
263 && !TYPE_OVERFLOW_TRAPS (type)
264 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
265 (trunc_mod @0 (convert @1))))
266
267 /* X - (X / Y) * Y is the same as X % Y. */
268 (simplify
269 (minus (convert1? @0) (convert2? (mult (trunc_div @0 @1) @1)))
270 (if (INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
271 (trunc_mod (convert @0) (convert @1))))
272
273 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
274 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
275 Also optimize A % (C << N) where C is a power of 2,
276 to A & ((C << N) - 1). */
277 (match (power_of_two_cand @1)
278 INTEGER_CST@1)
279 (match (power_of_two_cand @1)
280 (lshift INTEGER_CST@1 @2))
281 (for mod (trunc_mod floor_mod)
282 (simplify
283 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
284 (if ((TYPE_UNSIGNED (type)
285 || tree_expr_nonnegative_p (@0))
286 && tree_nop_conversion_p (type, TREE_TYPE (@3))
287 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
288 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
289
290 /* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF. */
291 (simplify
292 (trunc_div (mult @0 integer_pow2p@1) @1)
293 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
294 (bit_and @0 { wide_int_to_tree
295 (type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
296 false, TYPE_PRECISION (type))); })))
297
298 /* Simplify (unsigned t / 2) * 2 -> unsigned t & ~1. */
299 (simplify
300 (mult (trunc_div @0 integer_pow2p@1) @1)
301 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
302 (bit_and @0 (negate @1))))
303
304 /* Simplify (t * 2) / 2) -> t. */
305 (for div (trunc_div ceil_div floor_div round_div exact_div)
306 (simplify
307 (div (mult @0 @1) @1)
308 (if (ANY_INTEGRAL_TYPE_P (type)
309 && TYPE_OVERFLOW_UNDEFINED (type))
310 @0)))
311
312 /* Simplify cos (-x) -> cos (x). */
313 (for op (negate abs)
314 (for coss (COS COSH)
315 (simplify
316 (coss (op @0))
317 (coss @0))))
318
319 /* X % Y is smaller than Y. */
320 (for cmp (lt ge)
321 (simplify
322 (cmp (trunc_mod @0 @1) @1)
323 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
324 { constant_boolean_node (cmp == LT_EXPR, type); })))
325 (for cmp (gt le)
326 (simplify
327 (cmp @1 (trunc_mod @0 @1))
328 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
329 { constant_boolean_node (cmp == GT_EXPR, type); })))
330
331 /* x | ~0 -> ~0 */
332 (simplify
333 (bit_ior @0 integer_all_onesp@1)
334 @1)
335
336 /* x & 0 -> 0 */
337 (simplify
338 (bit_and @0 integer_zerop@1)
339 @1)
340
341 /* ~x | x -> -1 */
342 /* ~x ^ x -> -1 */
343 /* ~x + x -> -1 */
344 (for op (bit_ior bit_xor plus)
345 (simplify
346 (op:c (convert? @0) (convert? (bit_not @0)))
347 (convert { build_all_ones_cst (TREE_TYPE (@0)); })))
348
349 /* x ^ x -> 0 */
350 (simplify
351 (bit_xor @0 @0)
352 { build_zero_cst (type); })
353
354 /* Canonicalize X ^ ~0 to ~X. */
355 (simplify
356 (bit_xor @0 integer_all_onesp@1)
357 (bit_not @0))
358
359 /* x & ~0 -> x */
360 (simplify
361 (bit_and @0 integer_all_onesp)
362 (non_lvalue @0))
363
364 /* x & x -> x, x | x -> x */
365 (for bitop (bit_and bit_ior)
366 (simplify
367 (bitop @0 @0)
368 (non_lvalue @0)))
369
370 /* x + (x & 1) -> (x + 1) & ~1 */
371 (simplify
372 (plus:c @0 (bit_and:s @0 integer_onep@1))
373 (bit_and (plus @0 @1) (bit_not @1)))
374
375 /* x & ~(x & y) -> x & ~y */
376 /* x | ~(x | y) -> x | ~y */
377 (for bitop (bit_and bit_ior)
378 (simplify
379 (bitop:c @0 (bit_not (bitop:cs @0 @1)))
380 (bitop @0 (bit_not @1))))
381
382 /* (x | y) & ~x -> y & ~x */
383 /* (x & y) | ~x -> y | ~x */
384 (for bitop (bit_and bit_ior)
385 rbitop (bit_ior bit_and)
386 (simplify
387 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
388 (bitop @1 @2)))
389
390 /* (x & y) ^ (x | y) -> x ^ y */
391 (simplify
392 (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
393 (bit_xor @0 @1))
394
395 /* (x ^ y) ^ (x | y) -> x & y */
396 (simplify
397 (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
398 (bit_and @0 @1))
399
400 /* (x & y) + (x ^ y) -> x | y */
401 /* (x & y) | (x ^ y) -> x | y */
402 /* (x & y) ^ (x ^ y) -> x | y */
403 (for op (plus bit_ior bit_xor)
404 (simplify
405 (op:c (bit_and @0 @1) (bit_xor @0 @1))
406 (bit_ior @0 @1)))
407
408 /* (x & y) + (x | y) -> x + y */
409 (simplify
410 (plus:c (bit_and @0 @1) (bit_ior @0 @1))
411 (plus @0 @1))
412
413 /* (x + y) - (x | y) -> x & y */
414 (simplify
415 (minus (plus @0 @1) (bit_ior @0 @1))
416 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
417 && !TYPE_SATURATING (type))
418 (bit_and @0 @1)))
419
420 /* (x + y) - (x & y) -> x | y */
421 (simplify
422 (minus (plus @0 @1) (bit_and @0 @1))
423 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
424 && !TYPE_SATURATING (type))
425 (bit_ior @0 @1)))
426
427 /* (x | y) - (x ^ y) -> x & y */
428 (simplify
429 (minus (bit_ior @0 @1) (bit_xor @0 @1))
430 (bit_and @0 @1))
431
432 /* (x | y) - (x & y) -> x ^ y */
433 (simplify
434 (minus (bit_ior @0 @1) (bit_and @0 @1))
435 (bit_xor @0 @1))
436
437 /* (x | y) & ~(x & y) -> x ^ y */
438 (simplify
439 (bit_and:c (bit_ior @0 @1) (bit_not (bit_and @0 @1)))
440 (bit_xor @0 @1))
441
442 /* (x | y) & (~x ^ y) -> x & y */
443 (simplify
444 (bit_and:c (bit_ior:c @0 @1) (bit_xor:c @1 (bit_not @0)))
445 (bit_and @0 @1))
446
447 /* ~x & ~y -> ~(x | y)
448 ~x | ~y -> ~(x & y) */
449 (for op (bit_and bit_ior)
450 rop (bit_ior bit_and)
451 (simplify
452 (op (convert1? (bit_not @0)) (convert2? (bit_not @1)))
453 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
454 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
455 (bit_not (rop (convert @0) (convert @1))))))
456
457 /* If we are XORing or adding two BIT_AND_EXPR's, both of which are and'ing
458 with a constant, and the two constants have no bits in common,
459 we should treat this as a BIT_IOR_EXPR since this may produce more
460 simplifications. */
461 (for op (bit_xor plus)
462 (simplify
463 (op (convert1? (bit_and@4 @0 INTEGER_CST@1))
464 (convert2? (bit_and@5 @2 INTEGER_CST@3)))
465 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
466 && tree_nop_conversion_p (type, TREE_TYPE (@2))
467 && wi::bit_and (@1, @3) == 0)
468 (bit_ior (convert @4) (convert @5)))))
469
470 /* (X | Y) ^ X -> Y & ~ X*/
471 (simplify
472 (bit_xor:c (convert? (bit_ior:c @0 @1)) (convert? @0))
473 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
474 (convert (bit_and @1 (bit_not @0)))))
475
476 /* Convert ~X ^ ~Y to X ^ Y. */
477 (simplify
478 (bit_xor (convert1? (bit_not @0)) (convert2? (bit_not @1)))
479 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
480 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
481 (bit_xor (convert @0) (convert @1))))
482
483 /* Convert ~X ^ C to X ^ ~C. */
484 (simplify
485 (bit_xor (convert? (bit_not @0)) INTEGER_CST@1)
486 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
487 (bit_xor (convert @0) (bit_not @1))))
488
489 /* Fold (X & Y) ^ Y as ~X & Y. */
490 (simplify
491 (bit_xor:c (bit_and:c @0 @1) @1)
492 (bit_and (bit_not @0) @1))
493
494 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
495 operands are another bit-wise operation with a common input. If so,
496 distribute the bit operations to save an operation and possibly two if
497 constants are involved. For example, convert
498 (A | B) & (A | C) into A | (B & C)
499 Further simplification will occur if B and C are constants. */
500 (for op (bit_and bit_ior)
501 rop (bit_ior bit_and)
502 (simplify
503 (op (convert? (rop:c @0 @1)) (convert? (rop @0 @2)))
504 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
505 (rop (convert @0) (op (convert @1) (convert @2))))))
506
507
508 (simplify
509 (abs (abs@1 @0))
510 @1)
511 (simplify
512 (abs (negate @0))
513 (abs @0))
514 (simplify
515 (abs tree_expr_nonnegative_p@0)
516 @0)
517
518 /* A few cases of fold-const.c negate_expr_p predicate. */
519 (match negate_expr_p
520 INTEGER_CST
521 (if ((INTEGRAL_TYPE_P (type)
522 && TYPE_OVERFLOW_WRAPS (type))
523 || (!TYPE_OVERFLOW_SANITIZED (type)
524 && may_negate_without_overflow_p (t)))))
525 (match negate_expr_p
526 FIXED_CST)
527 (match negate_expr_p
528 (negate @0)
529 (if (!TYPE_OVERFLOW_SANITIZED (type))))
530 (match negate_expr_p
531 REAL_CST
532 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (t)))))
533 /* VECTOR_CST handling of non-wrapping types would recurse in unsupported
534 ways. */
535 (match negate_expr_p
536 VECTOR_CST
537 (if (FLOAT_TYPE_P (TREE_TYPE (type)) || TYPE_OVERFLOW_WRAPS (type))))
538
539 /* -(A + B) -> (-B) - A. */
540 (simplify
541 (negate (plus:c @0 negate_expr_p@1))
542 (if (!HONOR_SIGN_DEPENDENT_ROUNDING (element_mode (type))
543 && !HONOR_SIGNED_ZEROS (element_mode (type)))
544 (minus (negate @1) @0)))
545
546 /* A - B -> A + (-B) if B is easily negatable. */
547 (simplify
548 (minus @0 negate_expr_p@1)
549 (if (!FIXED_POINT_TYPE_P (type))
550 (plus @0 (negate @1))))
551
552 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
553 when profitable.
554 For bitwise binary operations apply operand conversions to the
555 binary operation result instead of to the operands. This allows
556 to combine successive conversions and bitwise binary operations.
557 We combine the above two cases by using a conditional convert. */
558 (for bitop (bit_and bit_ior bit_xor)
559 (simplify
560 (bitop (convert @0) (convert? @1))
561 (if (((TREE_CODE (@1) == INTEGER_CST
562 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
563 && int_fits_type_p (@1, TREE_TYPE (@0)))
564 || types_match (@0, @1))
565 /* ??? This transform conflicts with fold-const.c doing
566 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
567 constants (if x has signed type, the sign bit cannot be set
568 in c). This folds extension into the BIT_AND_EXPR.
569 Restrict it to GIMPLE to avoid endless recursions. */
570 && (bitop != BIT_AND_EXPR || GIMPLE)
571 && (/* That's a good idea if the conversion widens the operand, thus
572 after hoisting the conversion the operation will be narrower. */
573 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
574 /* It's also a good idea if the conversion is to a non-integer
575 mode. */
576 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
577 /* Or if the precision of TO is not the same as the precision
578 of its mode. */
579 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
580 (convert (bitop @0 (convert @1))))))
581
582 (for bitop (bit_and bit_ior)
583 rbitop (bit_ior bit_and)
584 /* (x | y) & x -> x */
585 /* (x & y) | x -> x */
586 (simplify
587 (bitop:c (rbitop:c @0 @1) @0)
588 @0)
589 /* (~x | y) & x -> x & y */
590 /* (~x & y) | x -> x | y */
591 (simplify
592 (bitop:c (rbitop:c (bit_not @0) @1) @0)
593 (bitop @0 @1)))
594
595 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
596 (for bitop (bit_and bit_ior bit_xor)
597 (simplify
598 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
599 (bit_and (bitop @0 @2) @1)))
600
601 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
602 (simplify
603 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
604 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
605
606 /* Combine successive equal operations with constants. */
607 (for bitop (bit_and bit_ior bit_xor)
608 (simplify
609 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
610 (bitop @0 (bitop @1 @2))))
611
612 /* Try simple folding for X op !X, and X op X with the help
613 of the truth_valued_p and logical_inverted_value predicates. */
614 (match truth_valued_p
615 @0
616 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
617 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
618 (match truth_valued_p
619 (op @0 @1)))
620 (match truth_valued_p
621 (truth_not @0))
622
623 (match (logical_inverted_value @0)
624 (bit_not truth_valued_p@0))
625 (match (logical_inverted_value @0)
626 (eq @0 integer_zerop))
627 (match (logical_inverted_value @0)
628 (ne truth_valued_p@0 integer_truep))
629 (match (logical_inverted_value @0)
630 (bit_xor truth_valued_p@0 integer_truep))
631
632 /* X & !X -> 0. */
633 (simplify
634 (bit_and:c @0 (logical_inverted_value @0))
635 { build_zero_cst (type); })
636 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
637 (for op (bit_ior bit_xor)
638 (simplify
639 (op:c truth_valued_p@0 (logical_inverted_value @0))
640 { constant_boolean_node (true, type); }))
641 /* X ==/!= !X is false/true. */
642 (for op (eq ne)
643 (simplify
644 (op:c truth_valued_p@0 (logical_inverted_value @0))
645 { constant_boolean_node (op == NE_EXPR ? true : false, type); }))
646
647 /* If arg1 and arg2 are booleans (or any single bit type)
648 then try to simplify:
649
650 (~X & Y) -> X < Y
651 (X & ~Y) -> Y < X
652 (~X | Y) -> X <= Y
653 (X | ~Y) -> Y <= X
654
655 But only do this if our result feeds into a comparison as
656 this transformation is not always a win, particularly on
657 targets with and-not instructions.
658 -> simplify_bitwise_binary_boolean */
659 (simplify
660 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
661 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
662 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
663 (lt @0 @1)))
664 (simplify
665 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
666 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
667 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
668 (le @0 @1)))
669
670 /* ~~x -> x */
671 (simplify
672 (bit_not (bit_not @0))
673 @0)
674
675 /* Convert ~ (-A) to A - 1. */
676 (simplify
677 (bit_not (convert? (negate @0)))
678 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
679 (convert (minus @0 { build_each_one_cst (TREE_TYPE (@0)); }))))
680
681 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
682 (simplify
683 (bit_not (convert? (minus @0 integer_each_onep)))
684 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
685 (convert (negate @0))))
686 (simplify
687 (bit_not (convert? (plus @0 integer_all_onesp)))
688 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
689 (convert (negate @0))))
690
691 /* Part of convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
692 (simplify
693 (bit_not (convert? (bit_xor @0 INTEGER_CST@1)))
694 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
695 (convert (bit_xor @0 (bit_not @1)))))
696 (simplify
697 (bit_not (convert? (bit_xor:c (bit_not @0) @1)))
698 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
699 (convert (bit_xor @0 @1))))
700
701 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
702 (simplify
703 (bit_ior:c (bit_and:cs @0 (bit_not @2)) (bit_and:cs @1 @2))
704 (bit_xor (bit_and (bit_xor @0 @1) @2) @0))
705
706 /* Fold A - (A & B) into ~B & A. */
707 (simplify
708 (minus (convert? @0) (convert?:s (bit_and:cs @0 @1)))
709 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
710 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
711 (convert (bit_and (bit_not @1) @0))))
712
713 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
714 (simplify
715 (pointer_plus (pointer_plus:s @0 @1) @3)
716 (pointer_plus @0 (plus @1 @3)))
717
718 /* Pattern match
719 tem1 = (long) ptr1;
720 tem2 = (long) ptr2;
721 tem3 = tem2 - tem1;
722 tem4 = (unsigned long) tem3;
723 tem5 = ptr1 + tem4;
724 and produce
725 tem5 = ptr2; */
726 (simplify
727 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
728 /* Conditionally look through a sign-changing conversion. */
729 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
730 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
731 || (GENERIC && type == TREE_TYPE (@1))))
732 @1))
733
734 /* Pattern match
735 tem = (sizetype) ptr;
736 tem = tem & algn;
737 tem = -tem;
738 ... = ptr p+ tem;
739 and produce the simpler and easier to analyze with respect to alignment
740 ... = ptr & ~algn; */
741 (simplify
742 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
743 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
744 (bit_and @0 { algn; })))
745
746 /* Try folding difference of addresses. */
747 (simplify
748 (minus (convert ADDR_EXPR@0) (convert @1))
749 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
750 (with { HOST_WIDE_INT diff; }
751 (if (ptr_difference_const (@0, @1, &diff))
752 { build_int_cst_type (type, diff); }))))
753 (simplify
754 (minus (convert @0) (convert ADDR_EXPR@1))
755 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
756 (with { HOST_WIDE_INT diff; }
757 (if (ptr_difference_const (@0, @1, &diff))
758 { build_int_cst_type (type, diff); }))))
759
760 /* If arg0 is derived from the address of an object or function, we may
761 be able to fold this expression using the object or function's
762 alignment. */
763 (simplify
764 (bit_and (convert? @0) INTEGER_CST@1)
765 (if (POINTER_TYPE_P (TREE_TYPE (@0))
766 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
767 (with
768 {
769 unsigned int align;
770 unsigned HOST_WIDE_INT bitpos;
771 get_pointer_alignment_1 (@0, &align, &bitpos);
772 }
773 (if (wi::ltu_p (@1, align / BITS_PER_UNIT))
774 { wide_int_to_tree (type, wi::bit_and (@1, bitpos / BITS_PER_UNIT)); }))))
775
776
777 /* We can't reassociate at all for saturating types. */
778 (if (!TYPE_SATURATING (type))
779
780 /* Contract negates. */
781 /* A + (-B) -> A - B */
782 (simplify
783 (plus:c (convert1? @0) (convert2? (negate @1)))
784 /* Apply STRIP_NOPS on @0 and the negate. */
785 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
786 && tree_nop_conversion_p (type, TREE_TYPE (@1))
787 && !TYPE_OVERFLOW_SANITIZED (type))
788 (minus (convert @0) (convert @1))))
789 /* A - (-B) -> A + B */
790 (simplify
791 (minus (convert1? @0) (convert2? (negate @1)))
792 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
793 && tree_nop_conversion_p (type, TREE_TYPE (@1))
794 && !TYPE_OVERFLOW_SANITIZED (type))
795 (plus (convert @0) (convert @1))))
796 /* -(-A) -> A */
797 (simplify
798 (negate (convert? (negate @1)))
799 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
800 && !TYPE_OVERFLOW_SANITIZED (type))
801 (convert @1)))
802
803 /* We can't reassociate floating-point unless -fassociative-math
804 or fixed-point plus or minus because of saturation to +-Inf. */
805 (if ((!FLOAT_TYPE_P (type) || flag_associative_math)
806 && !FIXED_POINT_TYPE_P (type))
807
808 /* Match patterns that allow contracting a plus-minus pair
809 irrespective of overflow issues. */
810 /* (A +- B) - A -> +- B */
811 /* (A +- B) -+ B -> A */
812 /* A - (A +- B) -> -+ B */
813 /* A +- (B -+ A) -> +- B */
814 (simplify
815 (minus (plus:c @0 @1) @0)
816 @1)
817 (simplify
818 (minus (minus @0 @1) @0)
819 (negate @1))
820 (simplify
821 (plus:c (minus @0 @1) @1)
822 @0)
823 (simplify
824 (minus @0 (plus:c @0 @1))
825 (negate @1))
826 (simplify
827 (minus @0 (minus @0 @1))
828 @1)
829
830 /* (A +- CST) +- CST -> A + CST */
831 (for outer_op (plus minus)
832 (for inner_op (plus minus)
833 (simplify
834 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
835 /* If the constant operation overflows we cannot do the transform
836 as we would introduce undefined overflow, for example
837 with (a - 1) + INT_MIN. */
838 (with { tree cst = fold_binary (outer_op == inner_op
839 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
840 (if (cst && !TREE_OVERFLOW (cst))
841 (inner_op @0 { cst; } ))))))
842
843 /* (CST - A) +- CST -> CST - A */
844 (for outer_op (plus minus)
845 (simplify
846 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
847 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
848 (if (cst && !TREE_OVERFLOW (cst))
849 (minus { cst; } @0)))))
850
851 /* ~A + A -> -1 */
852 (simplify
853 (plus:c (bit_not @0) @0)
854 (if (!TYPE_OVERFLOW_TRAPS (type))
855 { build_all_ones_cst (type); }))
856
857 /* ~A + 1 -> -A */
858 (simplify
859 (plus (convert? (bit_not @0)) integer_each_onep)
860 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
861 (negate (convert @0))))
862
863 /* -A - 1 -> ~A */
864 (simplify
865 (minus (convert? (negate @0)) integer_each_onep)
866 (if (!TYPE_OVERFLOW_TRAPS (type)
867 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
868 (bit_not (convert @0))))
869
870 /* -1 - A -> ~A */
871 (simplify
872 (minus integer_all_onesp @0)
873 (bit_not @0))
874
875 /* (T)(P + A) - (T)P -> (T) A */
876 (for add (plus pointer_plus)
877 (simplify
878 (minus (convert (add @0 @1))
879 (convert @0))
880 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
881 /* For integer types, if A has a smaller type
882 than T the result depends on the possible
883 overflow in P + A.
884 E.g. T=size_t, A=(unsigned)429497295, P>0.
885 However, if an overflow in P + A would cause
886 undefined behavior, we can assume that there
887 is no overflow. */
888 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
889 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
890 /* For pointer types, if the conversion of A to the
891 final type requires a sign- or zero-extension,
892 then we have to punt - it is not defined which
893 one is correct. */
894 || (POINTER_TYPE_P (TREE_TYPE (@0))
895 && TREE_CODE (@1) == INTEGER_CST
896 && tree_int_cst_sign_bit (@1) == 0))
897 (convert @1))))))
898
899
900 /* Simplifications of MIN_EXPR and MAX_EXPR. */
901
902 (for minmax (min max)
903 (simplify
904 (minmax @0 @0)
905 @0))
906 (simplify
907 (min @0 @1)
908 (if (INTEGRAL_TYPE_P (type)
909 && TYPE_MIN_VALUE (type)
910 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
911 @1))
912 (simplify
913 (max @0 @1)
914 (if (INTEGRAL_TYPE_P (type)
915 && TYPE_MAX_VALUE (type)
916 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
917 @1))
918
919
920 /* Simplifications of shift and rotates. */
921
922 (for rotate (lrotate rrotate)
923 (simplify
924 (rotate integer_all_onesp@0 @1)
925 @0))
926
927 /* Optimize -1 >> x for arithmetic right shifts. */
928 (simplify
929 (rshift integer_all_onesp@0 @1)
930 (if (!TYPE_UNSIGNED (type)
931 && tree_expr_nonnegative_p (@1))
932 @0))
933
934 /* Optimize (x >> c) << c into x & (-1<<c). */
935 (simplify
936 (lshift (rshift @0 INTEGER_CST@1) @1)
937 (if (wi::ltu_p (@1, element_precision (type)))
938 (bit_and @0 (lshift { build_minus_one_cst (type); } @1))))
939
940 /* Optimize (x << c) >> c into x & ((unsigned)-1 >> c) for unsigned
941 types. */
942 (simplify
943 (rshift (lshift @0 INTEGER_CST@1) @1)
944 (if (TYPE_UNSIGNED (type)
945 && (wi::ltu_p (@1, element_precision (type))))
946 (bit_and @0 (rshift { build_minus_one_cst (type); } @1))))
947
948 (for shiftrotate (lrotate rrotate lshift rshift)
949 (simplify
950 (shiftrotate @0 integer_zerop)
951 (non_lvalue @0))
952 (simplify
953 (shiftrotate integer_zerop@0 @1)
954 @0)
955 /* Prefer vector1 << scalar to vector1 << vector2
956 if vector2 is uniform. */
957 (for vec (VECTOR_CST CONSTRUCTOR)
958 (simplify
959 (shiftrotate @0 vec@1)
960 (with { tree tem = uniform_vector_p (@1); }
961 (if (tem)
962 (shiftrotate @0 { tem; }))))))
963
964 /* Rewrite an LROTATE_EXPR by a constant into an
965 RROTATE_EXPR by a new constant. */
966 (simplify
967 (lrotate @0 INTEGER_CST@1)
968 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
969 build_int_cst (TREE_TYPE (@1),
970 element_precision (type)), @1); }))
971
972 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
973 (for op (lrotate rrotate rshift lshift)
974 (simplify
975 (op (op @0 INTEGER_CST@1) INTEGER_CST@2)
976 (with { unsigned int prec = element_precision (type); }
977 (if (wi::ge_p (@1, 0, TYPE_SIGN (TREE_TYPE (@1)))
978 && wi::lt_p (@1, prec, TYPE_SIGN (TREE_TYPE (@1)))
979 && wi::ge_p (@2, 0, TYPE_SIGN (TREE_TYPE (@2)))
980 && wi::lt_p (@2, prec, TYPE_SIGN (TREE_TYPE (@2))))
981 (with { unsigned int low = wi::add (@1, @2).to_uhwi (); }
982 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
983 being well defined. */
984 (if (low >= prec)
985 (if (op == LROTATE_EXPR || op == RROTATE_EXPR)
986 (op @0 { build_int_cst (TREE_TYPE (@1), low % prec); })
987 (if (TYPE_UNSIGNED (type) || op == LSHIFT_EXPR)
988 { build_zero_cst (type); }
989 (op @0 { build_int_cst (TREE_TYPE (@1), prec - 1); })))
990 (op @0 { build_int_cst (TREE_TYPE (@1), low); })))))))
991
992
993 /* ((1 << A) & 1) != 0 -> A == 0
994 ((1 << A) & 1) == 0 -> A != 0 */
995 (for cmp (ne eq)
996 icmp (eq ne)
997 (simplify
998 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
999 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
1000
1001 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
1002 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
1003 if CST2 != 0. */
1004 (for cmp (ne eq)
1005 (simplify
1006 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
1007 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
1008 (if (cand < 0
1009 || (!integer_zerop (@2)
1010 && wi::ne_p (wi::lshift (@0, cand), @2)))
1011 { constant_boolean_node (cmp == NE_EXPR, type); }
1012 (if (!integer_zerop (@2)
1013 && wi::eq_p (wi::lshift (@0, cand), @2))
1014 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); }))))))
1015
1016 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
1017 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
1018 if the new mask might be further optimized. */
1019 (for shift (lshift rshift)
1020 (simplify
1021 (bit_and (convert?:s@4 (shift:s@5 (convert1?@3 @0) INTEGER_CST@1))
1022 INTEGER_CST@2)
1023 (if (tree_nop_conversion_p (TREE_TYPE (@4), TREE_TYPE (@5))
1024 && TYPE_PRECISION (type) <= HOST_BITS_PER_WIDE_INT
1025 && tree_fits_uhwi_p (@1)
1026 && tree_to_uhwi (@1) > 0
1027 && tree_to_uhwi (@1) < TYPE_PRECISION (type))
1028 (with
1029 {
1030 unsigned int shiftc = tree_to_uhwi (@1);
1031 unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (@2);
1032 unsigned HOST_WIDE_INT newmask, zerobits = 0;
1033 tree shift_type = TREE_TYPE (@3);
1034 unsigned int prec;
1035
1036 if (shift == LSHIFT_EXPR)
1037 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
1038 else if (shift == RSHIFT_EXPR
1039 && (TYPE_PRECISION (shift_type)
1040 == GET_MODE_PRECISION (TYPE_MODE (shift_type))))
1041 {
1042 prec = TYPE_PRECISION (TREE_TYPE (@3));
1043 tree arg00 = @0;
1044 /* See if more bits can be proven as zero because of
1045 zero extension. */
1046 if (@3 != @0
1047 && TYPE_UNSIGNED (TREE_TYPE (@0)))
1048 {
1049 tree inner_type = TREE_TYPE (@0);
1050 if ((TYPE_PRECISION (inner_type)
1051 == GET_MODE_PRECISION (TYPE_MODE (inner_type)))
1052 && TYPE_PRECISION (inner_type) < prec)
1053 {
1054 prec = TYPE_PRECISION (inner_type);
1055 /* See if we can shorten the right shift. */
1056 if (shiftc < prec)
1057 shift_type = inner_type;
1058 /* Otherwise X >> C1 is all zeros, so we'll optimize
1059 it into (X, 0) later on by making sure zerobits
1060 is all ones. */
1061 }
1062 }
1063 zerobits = ~(unsigned HOST_WIDE_INT) 0;
1064 if (shiftc < prec)
1065 {
1066 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
1067 zerobits <<= prec - shiftc;
1068 }
1069 /* For arithmetic shift if sign bit could be set, zerobits
1070 can contain actually sign bits, so no transformation is
1071 possible, unless MASK masks them all away. In that
1072 case the shift needs to be converted into logical shift. */
1073 if (!TYPE_UNSIGNED (TREE_TYPE (@3))
1074 && prec == TYPE_PRECISION (TREE_TYPE (@3)))
1075 {
1076 if ((mask & zerobits) == 0)
1077 shift_type = unsigned_type_for (TREE_TYPE (@3));
1078 else
1079 zerobits = 0;
1080 }
1081 }
1082 }
1083 /* ((X << 16) & 0xff00) is (X, 0). */
1084 (if ((mask & zerobits) == mask)
1085 { build_int_cst (type, 0); }
1086 (with { newmask = mask | zerobits; }
1087 (if (newmask != mask && (newmask & (newmask + 1)) == 0)
1088 (with
1089 {
1090 /* Only do the transformation if NEWMASK is some integer
1091 mode's mask. */
1092 for (prec = BITS_PER_UNIT;
1093 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
1094 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
1095 break;
1096 }
1097 (if (prec < HOST_BITS_PER_WIDE_INT
1098 || newmask == ~(unsigned HOST_WIDE_INT) 0)
1099 (with
1100 { tree newmaskt = build_int_cst_type (TREE_TYPE (@2), newmask); }
1101 (if (!tree_int_cst_equal (newmaskt, @2))
1102 (if (shift_type != TREE_TYPE (@3))
1103 (bit_and (convert (shift:shift_type (convert @3) @1)) { newmaskt; })
1104 (bit_and @4 { newmaskt; })))))))))))))
1105
1106 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
1107 (X & C2) >> C1 into (X >> C1) & (C2 >> C1). */
1108 (for shift (lshift rshift)
1109 (simplify
1110 (shift (convert?:s (bit_and:s @0 INTEGER_CST@2)) INTEGER_CST@1)
1111 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
1112 (with { tree mask = int_const_binop (shift, fold_convert (type, @2), @1); }
1113 (bit_and (shift (convert @0) @1) { mask; })))))
1114
1115
1116 /* Simplifications of conversions. */
1117
1118 /* Basic strip-useless-type-conversions / strip_nops. */
1119 (for cvt (convert view_convert float fix_trunc)
1120 (simplify
1121 (cvt @0)
1122 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
1123 || (GENERIC && type == TREE_TYPE (@0)))
1124 @0)))
1125
1126 /* Contract view-conversions. */
1127 (simplify
1128 (view_convert (view_convert @0))
1129 (view_convert @0))
1130
1131 /* For integral conversions with the same precision or pointer
1132 conversions use a NOP_EXPR instead. */
1133 (simplify
1134 (view_convert @0)
1135 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
1136 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1137 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
1138 (convert @0)))
1139
1140 /* Strip inner integral conversions that do not change precision or size. */
1141 (simplify
1142 (view_convert (convert@0 @1))
1143 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1144 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1145 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
1146 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
1147 (view_convert @1)))
1148
1149 /* Re-association barriers around constants and other re-association
1150 barriers can be removed. */
1151 (simplify
1152 (paren CONSTANT_CLASS_P@0)
1153 @0)
1154 (simplify
1155 (paren (paren@1 @0))
1156 @1)
1157
1158 /* Handle cases of two conversions in a row. */
1159 (for ocvt (convert float fix_trunc)
1160 (for icvt (convert float)
1161 (simplify
1162 (ocvt (icvt@1 @0))
1163 (with
1164 {
1165 tree inside_type = TREE_TYPE (@0);
1166 tree inter_type = TREE_TYPE (@1);
1167 int inside_int = INTEGRAL_TYPE_P (inside_type);
1168 int inside_ptr = POINTER_TYPE_P (inside_type);
1169 int inside_float = FLOAT_TYPE_P (inside_type);
1170 int inside_vec = VECTOR_TYPE_P (inside_type);
1171 unsigned int inside_prec = TYPE_PRECISION (inside_type);
1172 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
1173 int inter_int = INTEGRAL_TYPE_P (inter_type);
1174 int inter_ptr = POINTER_TYPE_P (inter_type);
1175 int inter_float = FLOAT_TYPE_P (inter_type);
1176 int inter_vec = VECTOR_TYPE_P (inter_type);
1177 unsigned int inter_prec = TYPE_PRECISION (inter_type);
1178 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
1179 int final_int = INTEGRAL_TYPE_P (type);
1180 int final_ptr = POINTER_TYPE_P (type);
1181 int final_float = FLOAT_TYPE_P (type);
1182 int final_vec = VECTOR_TYPE_P (type);
1183 unsigned int final_prec = TYPE_PRECISION (type);
1184 int final_unsignedp = TYPE_UNSIGNED (type);
1185 }
1186 (switch
1187 /* In addition to the cases of two conversions in a row
1188 handled below, if we are converting something to its own
1189 type via an object of identical or wider precision, neither
1190 conversion is needed. */
1191 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
1192 || (GENERIC
1193 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
1194 && (((inter_int || inter_ptr) && final_int)
1195 || (inter_float && final_float))
1196 && inter_prec >= final_prec)
1197 (ocvt @0))
1198
1199 /* Likewise, if the intermediate and initial types are either both
1200 float or both integer, we don't need the middle conversion if the
1201 former is wider than the latter and doesn't change the signedness
1202 (for integers). Avoid this if the final type is a pointer since
1203 then we sometimes need the middle conversion. Likewise if the
1204 final type has a precision not equal to the size of its mode. */
1205 (if (((inter_int && inside_int) || (inter_float && inside_float))
1206 && (final_int || final_float)
1207 && inter_prec >= inside_prec
1208 && (inter_float || inter_unsignedp == inside_unsignedp)
1209 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1210 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1211 (ocvt @0))
1212
1213 /* If we have a sign-extension of a zero-extended value, we can
1214 replace that by a single zero-extension. Likewise if the
1215 final conversion does not change precision we can drop the
1216 intermediate conversion. */
1217 (if (inside_int && inter_int && final_int
1218 && ((inside_prec < inter_prec && inter_prec < final_prec
1219 && inside_unsignedp && !inter_unsignedp)
1220 || final_prec == inter_prec))
1221 (ocvt @0))
1222
1223 /* Two conversions in a row are not needed unless:
1224 - some conversion is floating-point (overstrict for now), or
1225 - some conversion is a vector (overstrict for now), or
1226 - the intermediate type is narrower than both initial and
1227 final, or
1228 - the intermediate type and innermost type differ in signedness,
1229 and the outermost type is wider than the intermediate, or
1230 - the initial type is a pointer type and the precisions of the
1231 intermediate and final types differ, or
1232 - the final type is a pointer type and the precisions of the
1233 initial and intermediate types differ. */
1234 (if (! inside_float && ! inter_float && ! final_float
1235 && ! inside_vec && ! inter_vec && ! final_vec
1236 && (inter_prec >= inside_prec || inter_prec >= final_prec)
1237 && ! (inside_int && inter_int
1238 && inter_unsignedp != inside_unsignedp
1239 && inter_prec < final_prec)
1240 && ((inter_unsignedp && inter_prec > inside_prec)
1241 == (final_unsignedp && final_prec > inter_prec))
1242 && ! (inside_ptr && inter_prec != final_prec)
1243 && ! (final_ptr && inside_prec != inter_prec)
1244 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1245 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1246 (ocvt @0))
1247
1248 /* A truncation to an unsigned type (a zero-extension) should be
1249 canonicalized as bitwise and of a mask. */
1250 (if (final_int && inter_int && inside_int
1251 && final_prec == inside_prec
1252 && final_prec > inter_prec
1253 && inter_unsignedp)
1254 (convert (bit_and @0 { wide_int_to_tree
1255 (inside_type,
1256 wi::mask (inter_prec, false,
1257 TYPE_PRECISION (inside_type))); })))
1258
1259 /* If we are converting an integer to a floating-point that can
1260 represent it exactly and back to an integer, we can skip the
1261 floating-point conversion. */
1262 (if (GIMPLE /* PR66211 */
1263 && inside_int && inter_float && final_int &&
1264 (unsigned) significand_size (TYPE_MODE (inter_type))
1265 >= inside_prec - !inside_unsignedp)
1266 (convert @0)))))))
1267
1268 /* If we have a narrowing conversion to an integral type that is fed by a
1269 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
1270 masks off bits outside the final type (and nothing else). */
1271 (simplify
1272 (convert (bit_and @0 INTEGER_CST@1))
1273 (if (INTEGRAL_TYPE_P (type)
1274 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1275 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
1276 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
1277 TYPE_PRECISION (type)), 0))
1278 (convert @0)))
1279
1280
1281 /* (X /[ex] A) * A -> X. */
1282 (simplify
1283 (mult (convert? (exact_div @0 @1)) @1)
1284 /* Look through a sign-changing conversion. */
1285 (convert @0))
1286
1287 /* Canonicalization of binary operations. */
1288
1289 /* Convert X + -C into X - C. */
1290 (simplify
1291 (plus @0 REAL_CST@1)
1292 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1293 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
1294 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1295 (minus @0 { tem; })))))
1296
1297 /* Convert x+x into x*2.0. */
1298 (simplify
1299 (plus @0 @0)
1300 (if (SCALAR_FLOAT_TYPE_P (type))
1301 (mult @0 { build_real (type, dconst2); })))
1302
1303 (simplify
1304 (minus integer_zerop @1)
1305 (negate @1))
1306
1307 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
1308 ARG0 is zero and X + ARG0 reduces to X, since that would mean
1309 (-ARG1 + ARG0) reduces to -ARG1. */
1310 (simplify
1311 (minus real_zerop@0 @1)
1312 (if (fold_real_zero_addition_p (type, @0, 0))
1313 (negate @1)))
1314
1315 /* Transform x * -1 into -x. */
1316 (simplify
1317 (mult @0 integer_minus_onep)
1318 (negate @0))
1319
1320 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
1321 (simplify
1322 (complex (realpart @0) (imagpart @0))
1323 @0)
1324 (simplify
1325 (realpart (complex @0 @1))
1326 @0)
1327 (simplify
1328 (imagpart (complex @0 @1))
1329 @1)
1330
1331 /* Sometimes we only care about half of a complex expression. */
1332 (simplify
1333 (realpart (convert?:s (conj:s @0)))
1334 (convert (realpart @0)))
1335 (simplify
1336 (imagpart (convert?:s (conj:s @0)))
1337 (convert (negate (imagpart @0))))
1338 (for part (realpart imagpart)
1339 (for op (plus minus)
1340 (simplify
1341 (part (convert?:s@2 (op:s @0 @1)))
1342 (convert (op (part @0) (part @1))))))
1343 (simplify
1344 (realpart (convert?:s (CEXPI:s @0)))
1345 (convert (COS @0)))
1346 (simplify
1347 (imagpart (convert?:s (CEXPI:s @0)))
1348 (convert (SIN @0)))
1349
1350 /* conj(conj(x)) -> x */
1351 (simplify
1352 (conj (convert? (conj @0)))
1353 (if (tree_nop_conversion_p (TREE_TYPE (@0), type))
1354 (convert @0)))
1355
1356 /* conj({x,y}) -> {x,-y} */
1357 (simplify
1358 (conj (convert?:s (complex:s @0 @1)))
1359 (with { tree itype = TREE_TYPE (type); }
1360 (complex (convert:itype @0) (negate (convert:itype @1)))))
1361
1362 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
1363 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
1364 (simplify
1365 (bswap (bswap @0))
1366 @0)
1367 (simplify
1368 (bswap (bit_not (bswap @0)))
1369 (bit_not @0))
1370 (for bitop (bit_xor bit_ior bit_and)
1371 (simplify
1372 (bswap (bitop:c (bswap @0) @1))
1373 (bitop @0 (bswap @1)))))
1374
1375
1376 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
1377
1378 /* Simplify constant conditions.
1379 Only optimize constant conditions when the selected branch
1380 has the same type as the COND_EXPR. This avoids optimizing
1381 away "c ? x : throw", where the throw has a void type.
1382 Note that we cannot throw away the fold-const.c variant nor
1383 this one as we depend on doing this transform before possibly
1384 A ? B : B -> B triggers and the fold-const.c one can optimize
1385 0 ? A : B to B even if A has side-effects. Something
1386 genmatch cannot handle. */
1387 (simplify
1388 (cond INTEGER_CST@0 @1 @2)
1389 (if (integer_zerop (@0))
1390 (if (!VOID_TYPE_P (TREE_TYPE (@2)) || VOID_TYPE_P (type))
1391 @2)
1392 (if (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))
1393 @1)))
1394 (simplify
1395 (vec_cond VECTOR_CST@0 @1 @2)
1396 (if (integer_all_onesp (@0))
1397 @1
1398 (if (integer_zerop (@0))
1399 @2)))
1400
1401 (for cnd (cond vec_cond)
1402 /* A ? B : (A ? X : C) -> A ? B : C. */
1403 (simplify
1404 (cnd @0 (cnd @0 @1 @2) @3)
1405 (cnd @0 @1 @3))
1406 (simplify
1407 (cnd @0 @1 (cnd @0 @2 @3))
1408 (cnd @0 @1 @3))
1409
1410 /* A ? B : B -> B. */
1411 (simplify
1412 (cnd @0 @1 @1)
1413 @1)
1414
1415 /* !A ? B : C -> A ? C : B. */
1416 (simplify
1417 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
1418 (cnd @0 @2 @1)))
1419
1420 /* A + (B vcmp C ? 1 : 0) -> A - (B vcmp C), since vector comparisons
1421 return all-1 or all-0 results. */
1422 /* ??? We could instead convert all instances of the vec_cond to negate,
1423 but that isn't necessarily a win on its own. */
1424 (simplify
1425 (plus:c @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1426 (if (VECTOR_TYPE_P (type)
1427 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1428 && (TYPE_MODE (TREE_TYPE (type))
1429 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1430 (minus @3 (view_convert @0))))
1431
1432 /* ... likewise A - (B vcmp C ? 1 : 0) -> A + (B vcmp C). */
1433 (simplify
1434 (minus @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1435 (if (VECTOR_TYPE_P (type)
1436 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1437 && (TYPE_MODE (TREE_TYPE (type))
1438 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1439 (plus @3 (view_convert @0))))
1440
1441
1442 /* Simplifications of comparisons. */
1443
1444 /* See if we can reduce the magnitude of a constant involved in a
1445 comparison by changing the comparison code. This is a canonicalization
1446 formerly done by maybe_canonicalize_comparison_1. */
1447 (for cmp (le gt)
1448 acmp (lt ge)
1449 (simplify
1450 (cmp @0 INTEGER_CST@1)
1451 (if (tree_int_cst_sgn (@1) == -1)
1452 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1453 (for cmp (ge lt)
1454 acmp (gt le)
1455 (simplify
1456 (cmp @0 INTEGER_CST@1)
1457 (if (tree_int_cst_sgn (@1) == 1)
1458 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1459
1460
1461 /* We can simplify a logical negation of a comparison to the
1462 inverted comparison. As we cannot compute an expression
1463 operator using invert_tree_comparison we have to simulate
1464 that with expression code iteration. */
1465 (for cmp (tcc_comparison)
1466 icmp (inverted_tcc_comparison)
1467 ncmp (inverted_tcc_comparison_with_nans)
1468 /* Ideally we'd like to combine the following two patterns
1469 and handle some more cases by using
1470 (logical_inverted_value (cmp @0 @1))
1471 here but for that genmatch would need to "inline" that.
1472 For now implement what forward_propagate_comparison did. */
1473 (simplify
1474 (bit_not (cmp @0 @1))
1475 (if (VECTOR_TYPE_P (type)
1476 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
1477 /* Comparison inversion may be impossible for trapping math,
1478 invert_tree_comparison will tell us. But we can't use
1479 a computed operator in the replacement tree thus we have
1480 to play the trick below. */
1481 (with { enum tree_code ic = invert_tree_comparison
1482 (cmp, HONOR_NANS (@0)); }
1483 (if (ic == icmp)
1484 (icmp @0 @1)
1485 (if (ic == ncmp)
1486 (ncmp @0 @1))))))
1487 (simplify
1488 (bit_xor (cmp @0 @1) integer_truep)
1489 (with { enum tree_code ic = invert_tree_comparison
1490 (cmp, HONOR_NANS (@0)); }
1491 (if (ic == icmp)
1492 (icmp @0 @1)
1493 (if (ic == ncmp)
1494 (ncmp @0 @1))))))
1495
1496 /* Transform comparisons of the form X - Y CMP 0 to X CMP Y.
1497 ??? The transformation is valid for the other operators if overflow
1498 is undefined for the type, but performing it here badly interacts
1499 with the transformation in fold_cond_expr_with_comparison which
1500 attempts to synthetize ABS_EXPR. */
1501 (for cmp (eq ne)
1502 (simplify
1503 (cmp (minus@2 @0 @1) integer_zerop)
1504 (if (single_use (@2))
1505 (cmp @0 @1))))
1506
1507 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
1508 signed arithmetic case. That form is created by the compiler
1509 often enough for folding it to be of value. One example is in
1510 computing loop trip counts after Operator Strength Reduction. */
1511 (for cmp (simple_comparison)
1512 scmp (swapped_simple_comparison)
1513 (simplify
1514 (cmp (mult @0 INTEGER_CST@1) integer_zerop@2)
1515 /* Handle unfolded multiplication by zero. */
1516 (if (integer_zerop (@1))
1517 (cmp @1 @2)
1518 (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1519 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
1520 /* If @1 is negative we swap the sense of the comparison. */
1521 (if (tree_int_cst_sgn (@1) < 0)
1522 (scmp @0 @2)
1523 (cmp @0 @2))))))
1524
1525 /* Simplify comparison of something with itself. For IEEE
1526 floating-point, we can only do some of these simplifications. */
1527 (simplify
1528 (eq @0 @0)
1529 (if (! FLOAT_TYPE_P (TREE_TYPE (@0))
1530 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1531 { constant_boolean_node (true, type); }))
1532 (for cmp (ge le)
1533 (simplify
1534 (cmp @0 @0)
1535 (eq @0 @0)))
1536 (for cmp (ne gt lt)
1537 (simplify
1538 (cmp @0 @0)
1539 (if (cmp != NE_EXPR
1540 || ! FLOAT_TYPE_P (TREE_TYPE (@0))
1541 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1542 { constant_boolean_node (false, type); })))
1543 (for cmp (unle unge uneq)
1544 (simplify
1545 (cmp @0 @0)
1546 { constant_boolean_node (true, type); }))
1547 (simplify
1548 (ltgt @0 @0)
1549 (if (!flag_trapping_math)
1550 { constant_boolean_node (false, type); }))
1551
1552 /* Fold ~X op ~Y as Y op X. */
1553 (for cmp (simple_comparison)
1554 (simplify
1555 (cmp (bit_not @0) (bit_not @1))
1556 (cmp @1 @0)))
1557
1558 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
1559 (for cmp (simple_comparison)
1560 scmp (swapped_simple_comparison)
1561 (simplify
1562 (cmp (bit_not @0) CONSTANT_CLASS_P@1)
1563 (if (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST)
1564 (scmp @0 (bit_not @1)))))
1565
1566 (for cmp (simple_comparison)
1567 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
1568 (simplify
1569 (cmp (convert@2 @0) (convert? @1))
1570 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1571 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1572 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@0)))
1573 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1574 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@1))))
1575 (with
1576 {
1577 tree type1 = TREE_TYPE (@1);
1578 if (TREE_CODE (@1) == REAL_CST && !DECIMAL_FLOAT_TYPE_P (type1))
1579 {
1580 REAL_VALUE_TYPE orig = TREE_REAL_CST (@1);
1581 if (TYPE_PRECISION (type1) > TYPE_PRECISION (float_type_node)
1582 && exact_real_truncate (TYPE_MODE (float_type_node), &orig))
1583 type1 = float_type_node;
1584 if (TYPE_PRECISION (type1) > TYPE_PRECISION (double_type_node)
1585 && exact_real_truncate (TYPE_MODE (double_type_node), &orig))
1586 type1 = double_type_node;
1587 }
1588 tree newtype
1589 = (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (type1)
1590 ? TREE_TYPE (@0) : type1);
1591 }
1592 (if (TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (newtype))
1593 (cmp (convert:newtype @0) (convert:newtype @1))))))
1594
1595 (simplify
1596 (cmp @0 REAL_CST@1)
1597 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
1598 (switch
1599 /* a CMP (-0) -> a CMP 0 */
1600 (if (REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (@1)))
1601 (cmp @0 { build_real (TREE_TYPE (@1), dconst0); }))
1602 /* x != NaN is always true, other ops are always false. */
1603 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1604 && ! HONOR_SNANS (@1))
1605 { constant_boolean_node (cmp == NE_EXPR, type); })
1606 /* Fold comparisons against infinity. */
1607 (if (REAL_VALUE_ISINF (TREE_REAL_CST (@1))
1608 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (@1))))
1609 (with
1610 {
1611 REAL_VALUE_TYPE max;
1612 enum tree_code code = cmp;
1613 bool neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1));
1614 if (neg)
1615 code = swap_tree_comparison (code);
1616 }
1617 (switch
1618 /* x > +Inf is always false, if with ignore sNANs. */
1619 (if (code == GT_EXPR
1620 && ! HONOR_SNANS (@0))
1621 { constant_boolean_node (false, type); })
1622 (if (code == LE_EXPR)
1623 /* x <= +Inf is always true, if we don't case about NaNs. */
1624 (if (! HONOR_NANS (@0))
1625 { constant_boolean_node (true, type); }
1626 /* x <= +Inf is the same as x == x, i.e. !isnan(x). */
1627 (eq @0 @0)))
1628 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
1629 (if (code == EQ_EXPR || code == GE_EXPR)
1630 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1631 (if (neg)
1632 (lt @0 { build_real (TREE_TYPE (@0), max); })
1633 (gt @0 { build_real (TREE_TYPE (@0), max); }))))
1634 /* x < +Inf is always equal to x <= DBL_MAX. */
1635 (if (code == LT_EXPR)
1636 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1637 (if (neg)
1638 (ge @0 { build_real (TREE_TYPE (@0), max); })
1639 (le @0 { build_real (TREE_TYPE (@0), max); }))))
1640 /* x != +Inf is always equal to !(x > DBL_MAX). */
1641 (if (code == NE_EXPR)
1642 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1643 (if (! HONOR_NANS (@0))
1644 (if (neg)
1645 (ge @0 { build_real (TREE_TYPE (@0), max); })
1646 (le @0 { build_real (TREE_TYPE (@0), max); }))
1647 (if (neg)
1648 (bit_xor (lt @0 { build_real (TREE_TYPE (@0), max); })
1649 { build_one_cst (type); })
1650 (bit_xor (gt @0 { build_real (TREE_TYPE (@0), max); })
1651 { build_one_cst (type); }))))))))))
1652
1653 /* If this is a comparison of a real constant with a PLUS_EXPR
1654 or a MINUS_EXPR of a real constant, we can convert it into a
1655 comparison with a revised real constant as long as no overflow
1656 occurs when unsafe_math_optimizations are enabled. */
1657 (if (flag_unsafe_math_optimizations)
1658 (for op (plus minus)
1659 (simplify
1660 (cmp (op @0 REAL_CST@1) REAL_CST@2)
1661 (with
1662 {
1663 tree tem = const_binop (op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR,
1664 TREE_TYPE (@1), @2, @1);
1665 }
1666 (if (tem && !TREE_OVERFLOW (tem))
1667 (cmp @0 { tem; }))))))
1668
1669 /* Likewise, we can simplify a comparison of a real constant with
1670 a MINUS_EXPR whose first operand is also a real constant, i.e.
1671 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
1672 floating-point types only if -fassociative-math is set. */
1673 (if (flag_associative_math)
1674 (simplify
1675 (cmp (minus REAL_CST@0 @1) REAL_CST@2)
1676 (with { tree tem = const_binop (MINUS_EXPR, TREE_TYPE (@1), @0, @2); }
1677 (if (tem && !TREE_OVERFLOW (tem))
1678 (cmp { tem; } @1)))))
1679
1680 /* Fold comparisons against built-in math functions. */
1681 (if (flag_unsafe_math_optimizations
1682 && ! flag_errno_math)
1683 (for sq (SQRT)
1684 (simplify
1685 (cmp (sq @0) REAL_CST@1)
1686 (switch
1687 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1688 (switch
1689 /* sqrt(x) < y is always false, if y is negative. */
1690 (if (cmp == EQ_EXPR || cmp == LT_EXPR || cmp == LE_EXPR)
1691 { constant_boolean_node (false, type); })
1692 /* sqrt(x) > y is always true, if y is negative and we
1693 don't care about NaNs, i.e. negative values of x. */
1694 (if (cmp == NE_EXPR || !HONOR_NANS (@0))
1695 { constant_boolean_node (true, type); })
1696 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
1697 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })))
1698 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1699 (with
1700 {
1701 REAL_VALUE_TYPE c2;
1702 REAL_ARITHMETIC (c2, MULT_EXPR,
1703 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1704 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1705 }
1706 (if (REAL_VALUE_ISINF (c2))
1707 /* sqrt(x) > y is x == +Inf, when y is very large. */
1708 (if (HONOR_INFINITIES (@0))
1709 (eq @0 { build_real (TREE_TYPE (@0), c2); })
1710 { constant_boolean_node (false, type); })
1711 /* sqrt(x) > c is the same as x > c*c. */
1712 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))
1713 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1714 (with
1715 {
1716 REAL_VALUE_TYPE c2;
1717 REAL_ARITHMETIC (c2, MULT_EXPR,
1718 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1719 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1720 }
1721 (if (REAL_VALUE_ISINF (c2))
1722 (switch
1723 /* sqrt(x) < y is always true, when y is a very large
1724 value and we don't care about NaNs or Infinities. */
1725 (if (! HONOR_NANS (@0) && ! HONOR_INFINITIES (@0))
1726 { constant_boolean_node (true, type); })
1727 /* sqrt(x) < y is x != +Inf when y is very large and we
1728 don't care about NaNs. */
1729 (if (! HONOR_NANS (@0))
1730 (ne @0 { build_real (TREE_TYPE (@0), c2); }))
1731 /* sqrt(x) < y is x >= 0 when y is very large and we
1732 don't care about Infinities. */
1733 (if (! HONOR_INFINITIES (@0))
1734 (ge @0 { build_real (TREE_TYPE (@0), dconst0); }))
1735 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
1736 (if (GENERIC)
1737 (truth_andif
1738 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1739 (ne @0 { build_real (TREE_TYPE (@0), c2); }))))
1740 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
1741 (if (! HONOR_NANS (@0))
1742 (cmp @0 { build_real (TREE_TYPE (@0), c2); })
1743 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
1744 (if (GENERIC)
1745 (truth_andif
1746 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1747 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))))))))))
1748
1749 /* Unordered tests if either argument is a NaN. */
1750 (simplify
1751 (bit_ior (unordered @0 @0) (unordered @1 @1))
1752 (if (types_match (@0, @1))
1753 (unordered @0 @1)))
1754 (simplify
1755 (bit_and (ordered @0 @0) (ordered @1 @1))
1756 (if (types_match (@0, @1))
1757 (ordered @0 @1)))
1758 (simplify
1759 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1760 @2)
1761 (simplify
1762 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1763 @2)
1764
1765 /* -A CMP -B -> B CMP A. */
1766 (for cmp (tcc_comparison)
1767 scmp (swapped_tcc_comparison)
1768 (simplify
1769 (cmp (negate @0) (negate @1))
1770 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1771 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1772 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1773 (scmp @0 @1)))
1774 (simplify
1775 (cmp (negate @0) CONSTANT_CLASS_P@1)
1776 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1777 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1778 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1779 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1780 (if (tem && !TREE_OVERFLOW (tem))
1781 (scmp @0 { tem; }))))))
1782
1783 /* Convert ABS_EXPR<x> == 0 or ABS_EXPR<x> != 0 to x == 0 or x != 0. */
1784 (for op (eq ne)
1785 (simplify
1786 (op (abs @0) zerop@1)
1787 (op @0 @1)))
1788
1789 /* From fold_sign_changed_comparison and fold_widened_comparison. */
1790 (for cmp (simple_comparison)
1791 (simplify
1792 (cmp (convert@0 @00) (convert?@1 @10))
1793 (if (TREE_CODE (TREE_TYPE (@0)) == INTEGER_TYPE
1794 /* Disable this optimization if we're casting a function pointer
1795 type on targets that require function pointer canonicalization. */
1796 && !(targetm.have_canonicalize_funcptr_for_compare ()
1797 && TREE_CODE (TREE_TYPE (@00)) == POINTER_TYPE
1798 && TREE_CODE (TREE_TYPE (TREE_TYPE (@00))) == FUNCTION_TYPE)
1799 && single_use (@0))
1800 (if (TYPE_PRECISION (TREE_TYPE (@00)) == TYPE_PRECISION (TREE_TYPE (@0))
1801 && (TREE_CODE (@10) == INTEGER_CST
1802 || (@1 != @10 && types_match (TREE_TYPE (@10), TREE_TYPE (@00))))
1803 && (TYPE_UNSIGNED (TREE_TYPE (@00)) == TYPE_UNSIGNED (TREE_TYPE (@0))
1804 || cmp == NE_EXPR
1805 || cmp == EQ_EXPR)
1806 && (POINTER_TYPE_P (TREE_TYPE (@00)) == POINTER_TYPE_P (TREE_TYPE (@0))))
1807 /* ??? The special-casing of INTEGER_CST conversion was in the original
1808 code and here to avoid a spurious overflow flag on the resulting
1809 constant which fold_convert produces. */
1810 (if (TREE_CODE (@1) == INTEGER_CST)
1811 (cmp @00 { force_fit_type (TREE_TYPE (@00), wi::to_widest (@1), 0,
1812 TREE_OVERFLOW (@1)); })
1813 (cmp @00 (convert @1)))
1814
1815 (if (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (TREE_TYPE (@00)))
1816 /* If possible, express the comparison in the shorter mode. */
1817 (if ((cmp == EQ_EXPR || cmp == NE_EXPR
1818 || TYPE_UNSIGNED (TREE_TYPE (@0)) == TYPE_UNSIGNED (TREE_TYPE (@00)))
1819 && (types_match (TREE_TYPE (@10), TREE_TYPE (@00))
1820 || ((TYPE_PRECISION (TREE_TYPE (@00))
1821 >= TYPE_PRECISION (TREE_TYPE (@10)))
1822 && (TYPE_UNSIGNED (TREE_TYPE (@00))
1823 == TYPE_UNSIGNED (TREE_TYPE (@10))))
1824 || (TREE_CODE (@10) == INTEGER_CST
1825 && (TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1826 || TREE_CODE (TREE_TYPE (@00)) == BOOLEAN_TYPE)
1827 && int_fits_type_p (@10, TREE_TYPE (@00)))))
1828 (cmp @00 (convert @10))
1829 (if (TREE_CODE (@10) == INTEGER_CST
1830 && TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1831 && !int_fits_type_p (@10, TREE_TYPE (@00)))
1832 (with
1833 {
1834 tree min = lower_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1835 tree max = upper_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1836 bool above = integer_nonzerop (const_binop (LT_EXPR, type, max, @10));
1837 bool below = integer_nonzerop (const_binop (LT_EXPR, type, @10, min));
1838 }
1839 (if (above || below)
1840 (if (cmp == EQ_EXPR || cmp == NE_EXPR)
1841 { constant_boolean_node (cmp == EQ_EXPR ? false : true, type); }
1842 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1843 { constant_boolean_node (above ? true : false, type); }
1844 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1845 { constant_boolean_node (above ? false : true, type); }))))))))))))
1846
1847 (for cmp (eq ne)
1848 /* A local variable can never be pointed to by
1849 the default SSA name of an incoming parameter.
1850 SSA names are canonicalized to 2nd place. */
1851 (simplify
1852 (cmp addr@0 SSA_NAME@1)
1853 (if (SSA_NAME_IS_DEFAULT_DEF (@1)
1854 && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL)
1855 (with { tree base = get_base_address (TREE_OPERAND (@0, 0)); }
1856 (if (TREE_CODE (base) == VAR_DECL
1857 && auto_var_in_fn_p (base, current_function_decl))
1858 (if (cmp == NE_EXPR)
1859 { constant_boolean_node (true, type); }
1860 { constant_boolean_node (false, type); }))))))
1861
1862 /* Equality compare simplifications from fold_binary */
1863 (for cmp (eq ne)
1864
1865 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
1866 Similarly for NE_EXPR. */
1867 (simplify
1868 (cmp (convert?@3 (bit_ior @0 INTEGER_CST@1)) INTEGER_CST@2)
1869 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0))
1870 && wi::bit_and_not (@1, @2) != 0)
1871 { constant_boolean_node (cmp == NE_EXPR, type); }))
1872
1873 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
1874 (simplify
1875 (cmp (bit_xor @0 @1) integer_zerop)
1876 (cmp @0 @1))
1877
1878 /* (X ^ Y) == Y becomes X == 0.
1879 Likewise (X ^ Y) == X becomes Y == 0. */
1880 (simplify
1881 (cmp:c (bit_xor:c @0 @1) @0)
1882 (cmp @1 { build_zero_cst (TREE_TYPE (@1)); }))
1883
1884 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
1885 (simplify
1886 (cmp (convert?@3 (bit_xor @0 INTEGER_CST@1)) INTEGER_CST@2)
1887 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0)))
1888 (cmp @0 (bit_xor @1 (convert @2)))))
1889
1890 (simplify
1891 (cmp (convert? addr@0) integer_zerop)
1892 (if (tree_single_nonzero_warnv_p (@0, NULL))
1893 { constant_boolean_node (cmp == NE_EXPR, type); })))
1894
1895 /* If we have (A & C) == C where C is a power of 2, convert this into
1896 (A & C) != 0. Similarly for NE_EXPR. */
1897 (for cmp (eq ne)
1898 icmp (ne eq)
1899 (simplify
1900 (cmp (bit_and@2 @0 integer_pow2p@1) @1)
1901 (icmp @2 { build_zero_cst (TREE_TYPE (@0)); })))
1902
1903 /* If we have (A & C) != 0 where C is the sign bit of A, convert
1904 this into A < 0. Similarly for (A & C) == 0 into A >= 0. */
1905 (for cmp (eq ne)
1906 ncmp (ge lt)
1907 (simplify
1908 (cmp (bit_and (convert?@2 @0) integer_pow2p@1) integer_zerop)
1909 (if (INTEGRAL_TYPE_P (TREE_TYPE (@0))
1910 && (TYPE_PRECISION (TREE_TYPE (@0))
1911 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
1912 && element_precision (@2) >= element_precision (@0)
1913 && wi::only_sign_bit_p (@1, element_precision (@0)))
1914 (with { tree stype = signed_type_for (TREE_TYPE (@0)); }
1915 (ncmp (convert:stype @0) { build_zero_cst (stype); })))))
1916
1917 /* When the addresses are not directly of decls compare base and offset.
1918 This implements some remaining parts of fold_comparison address
1919 comparisons but still no complete part of it. Still it is good
1920 enough to make fold_stmt not regress when not dispatching to fold_binary. */
1921 (for cmp (simple_comparison)
1922 (simplify
1923 (cmp (convert1?@2 addr@0) (convert2? addr@1))
1924 (with
1925 {
1926 HOST_WIDE_INT off0, off1;
1927 tree base0 = get_addr_base_and_unit_offset (TREE_OPERAND (@0, 0), &off0);
1928 tree base1 = get_addr_base_and_unit_offset (TREE_OPERAND (@1, 0), &off1);
1929 if (base0 && TREE_CODE (base0) == MEM_REF)
1930 {
1931 off0 += mem_ref_offset (base0).to_short_addr ();
1932 base0 = TREE_OPERAND (base0, 0);
1933 }
1934 if (base1 && TREE_CODE (base1) == MEM_REF)
1935 {
1936 off1 += mem_ref_offset (base1).to_short_addr ();
1937 base1 = TREE_OPERAND (base1, 0);
1938 }
1939 }
1940 (if (base0 && base1)
1941 (with
1942 {
1943 int equal = 2;
1944 if (decl_in_symtab_p (base0)
1945 && decl_in_symtab_p (base1))
1946 equal = symtab_node::get_create (base0)
1947 ->equal_address_to (symtab_node::get_create (base1));
1948 else if ((DECL_P (base0) || TREE_CODE (base0) == SSA_NAME)
1949 && (DECL_P (base1) || TREE_CODE (base1) == SSA_NAME))
1950 equal = (base0 == base1);
1951 }
1952 (if (equal == 1
1953 && (cmp == EQ_EXPR || cmp == NE_EXPR
1954 /* If the offsets are equal we can ignore overflow. */
1955 || off0 == off1
1956 || POINTER_TYPE_OVERFLOW_UNDEFINED
1957 /* Or if we compare using pointers to decls. */
1958 || (POINTER_TYPE_P (TREE_TYPE (@2))
1959 && DECL_P (base0))))
1960 (switch
1961 (if (cmp == EQ_EXPR)
1962 { constant_boolean_node (off0 == off1, type); })
1963 (if (cmp == NE_EXPR)
1964 { constant_boolean_node (off0 != off1, type); })
1965 (if (cmp == LT_EXPR)
1966 { constant_boolean_node (off0 < off1, type); })
1967 (if (cmp == LE_EXPR)
1968 { constant_boolean_node (off0 <= off1, type); })
1969 (if (cmp == GE_EXPR)
1970 { constant_boolean_node (off0 >= off1, type); })
1971 (if (cmp == GT_EXPR)
1972 { constant_boolean_node (off0 > off1, type); }))
1973 (if (equal == 0
1974 && DECL_P (base0) && DECL_P (base1)
1975 /* If we compare this as integers require equal offset. */
1976 && (!INTEGRAL_TYPE_P (TREE_TYPE (@2))
1977 || off0 == off1))
1978 (switch
1979 (if (cmp == EQ_EXPR)
1980 { constant_boolean_node (false, type); })
1981 (if (cmp == NE_EXPR)
1982 { constant_boolean_node (true, type); })))))))))
1983
1984 /* Non-equality compare simplifications from fold_binary */
1985 (for cmp (lt gt le ge)
1986 /* Comparisons with the highest or lowest possible integer of
1987 the specified precision will have known values. */
1988 (simplify
1989 (cmp (convert?@2 @0) INTEGER_CST@1)
1990 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1991 && tree_nop_conversion_p (TREE_TYPE (@2), TREE_TYPE (@0)))
1992 (with
1993 {
1994 tree arg1_type = TREE_TYPE (@1);
1995 unsigned int prec = TYPE_PRECISION (arg1_type);
1996 wide_int max = wi::max_value (arg1_type);
1997 wide_int signed_max = wi::max_value (prec, SIGNED);
1998 wide_int min = wi::min_value (arg1_type);
1999 }
2000 (switch
2001 (if (wi::eq_p (@1, max))
2002 (switch
2003 (if (cmp == GT_EXPR)
2004 { constant_boolean_node (false, type); })
2005 (if (cmp == GE_EXPR)
2006 (eq @2 @1))
2007 (if (cmp == LE_EXPR)
2008 { constant_boolean_node (true, type); })
2009 (if (cmp == LT_EXPR)
2010 (ne @2 @1))))
2011 (if (wi::eq_p (@1, min))
2012 (switch
2013 (if (cmp == LT_EXPR)
2014 { constant_boolean_node (false, type); })
2015 (if (cmp == LE_EXPR)
2016 (eq @2 @1))
2017 (if (cmp == GE_EXPR)
2018 { constant_boolean_node (true, type); })
2019 (if (cmp == GT_EXPR)
2020 (ne @2 @1))))
2021 (if (wi::eq_p (@1, max - 1))
2022 (switch
2023 (if (cmp == GT_EXPR)
2024 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))
2025 (if (cmp == LE_EXPR)
2026 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
2027 (if (wi::eq_p (@1, min + 1))
2028 (switch
2029 (if (cmp == GE_EXPR)
2030 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))
2031 (if (cmp == LT_EXPR)
2032 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
2033 (if (wi::eq_p (@1, signed_max)
2034 && TYPE_UNSIGNED (arg1_type)
2035 /* We will flip the signedness of the comparison operator
2036 associated with the mode of @1, so the sign bit is
2037 specified by this mode. Check that @1 is the signed
2038 max associated with this sign bit. */
2039 && prec == GET_MODE_PRECISION (TYPE_MODE (arg1_type))
2040 /* signed_type does not work on pointer types. */
2041 && INTEGRAL_TYPE_P (arg1_type))
2042 /* The following case also applies to X < signed_max+1
2043 and X >= signed_max+1 because previous transformations. */
2044 (if (cmp == LE_EXPR || cmp == GT_EXPR)
2045 (with { tree st = signed_type_for (arg1_type); }
2046 (if (cmp == LE_EXPR)
2047 (ge (convert:st @0) { build_zero_cst (st); })
2048 (lt (convert:st @0) { build_zero_cst (st); }))))))))))
2049
2050 (for cmp (unordered ordered unlt unle ungt unge uneq ltgt)
2051 /* If the second operand is NaN, the result is constant. */
2052 (simplify
2053 (cmp @0 REAL_CST@1)
2054 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
2055 && (cmp != LTGT_EXPR || ! flag_trapping_math))
2056 { constant_boolean_node (cmp == ORDERED_EXPR || cmp == LTGT_EXPR
2057 ? false : true, type); })))
2058
2059 /* bool_var != 0 becomes bool_var. */
2060 (simplify
2061 (ne @0 integer_zerop)
2062 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
2063 && types_match (type, TREE_TYPE (@0)))
2064 (non_lvalue @0)))
2065 /* bool_var == 1 becomes bool_var. */
2066 (simplify
2067 (eq @0 integer_onep)
2068 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
2069 && types_match (type, TREE_TYPE (@0)))
2070 (non_lvalue @0)))
2071 /* Do not handle
2072 bool_var == 0 becomes !bool_var or
2073 bool_var != 1 becomes !bool_var
2074 here because that only is good in assignment context as long
2075 as we require a tcc_comparison in GIMPLE_CONDs where we'd
2076 replace if (x == 0) with tem = ~x; if (tem != 0) which is
2077 clearly less optimal and which we'll transform again in forwprop. */
2078
2079
2080 /* Simplification of math builtins. */
2081
2082 /* fold_builtin_logarithm */
2083 (if (flag_unsafe_math_optimizations)
2084
2085 /* Simplify sqrt(x) * sqrt(x) -> x. */
2086 (simplify
2087 (mult (SQRT@1 @0) @1)
2088 (if (!HONOR_SNANS (type))
2089 @0))
2090
2091 /* Simplify sqrt(x) * sqrt(y) -> sqrt(x*y). */
2092 (for root (SQRT CBRT)
2093 (simplify
2094 (mult (root:s @0) (root:s @1))
2095 (root (mult @0 @1))))
2096
2097 /* Simplify pow(x,y) * pow(x,z) -> pow(x,y+z). */
2098 (simplify
2099 (mult (POW:s @0 @1) (POW:s @0 @2))
2100 (POW @0 (plus @1 @2)))
2101
2102 /* Simplify pow(x,y) * pow(z,y) -> pow(x*z,y). */
2103 (simplify
2104 (mult (POW:s @0 @1) (POW:s @2 @1))
2105 (POW (mult @0 @2) @1))
2106
2107 /* Simplify expN(x) * expN(y) -> expN(x+y). */
2108 (for exps (EXP EXP2 EXP10 POW10)
2109 (simplify
2110 (mult (exps:s @0) (exps:s @1))
2111 (exps (plus @0 @1))))
2112
2113 /* Simplify tan(x) * cos(x) -> sin(x). */
2114 (simplify
2115 (mult:c (TAN:s @0) (COS:s @0))
2116 (SIN @0))
2117
2118 /* Simplify x * pow(x,c) -> pow(x,c+1). */
2119 (simplify
2120 (mult @0 (POW:s @0 REAL_CST@1))
2121 (if (!TREE_OVERFLOW (@1))
2122 (POW @0 (plus @1 { build_one_cst (type); }))))
2123
2124 /* Simplify sin(x) / cos(x) -> tan(x). */
2125 (simplify
2126 (rdiv (SIN:s @0) (COS:s @0))
2127 (TAN @0))
2128
2129 /* Simplify cos(x) / sin(x) -> 1 / tan(x). */
2130 (simplify
2131 (rdiv (COS:s @0) (SIN:s @0))
2132 (rdiv { build_one_cst (type); } (TAN @0)))
2133
2134 /* Simplify sin(x) / tan(x) -> cos(x). */
2135 (simplify
2136 (rdiv (SIN:s @0) (TAN:s @0))
2137 (if (! HONOR_NANS (@0)
2138 && ! HONOR_INFINITIES (@0))
2139 (cos @0)))
2140
2141 /* Simplify tan(x) / sin(x) -> 1.0 / cos(x). */
2142 (simplify
2143 (rdiv (TAN:s @0) (SIN:s @0))
2144 (if (! HONOR_NANS (@0)
2145 && ! HONOR_INFINITIES (@0))
2146 (rdiv { build_one_cst (type); } (COS @0))))
2147
2148 /* Simplify pow(x,c) / x -> pow(x,c-1). */
2149 (simplify
2150 (rdiv (POW:s @0 REAL_CST@1) @0)
2151 (if (!TREE_OVERFLOW (@1))
2152 (POW @0 (minus @1 { build_one_cst (type); }))))
2153
2154 /* Simplify a/root(b/c) into a*root(c/b). */
2155 (for root (SQRT CBRT)
2156 (simplify
2157 (rdiv @0 (root:s (rdiv:s @1 @2)))
2158 (mult @0 (root (rdiv @2 @1)))))
2159
2160 /* Simplify x/expN(y) into x*expN(-y). */
2161 (for exps (EXP EXP2 EXP10 POW10)
2162 (simplify
2163 (rdiv @0 (exps:s @1))
2164 (mult @0 (exps (negate @1)))))
2165
2166 /* Simplify x / pow (y,z) -> x * pow(y,-z). */
2167 (simplify
2168 (rdiv @0 (POW:s @1 @2))
2169 (mult @0 (POW @1 (negate @2))))
2170
2171 /* Special case, optimize logN(expN(x)) = x. */
2172 (for logs (LOG LOG2 LOG10)
2173 exps (EXP EXP2 EXP10)
2174 (simplify
2175 (logs (exps @0))
2176 @0))
2177 /* Optimize logN(func()) for various exponential functions. We
2178 want to determine the value "x" and the power "exponent" in
2179 order to transform logN(x**exponent) into exponent*logN(x). */
2180 (for logs (LOG LOG LOG LOG
2181 LOG2 LOG2 LOG2 LOG2
2182 LOG10 LOG10 LOG10 LOG10)
2183 exps (EXP EXP2 EXP10 POW10)
2184 (simplify
2185 (logs (exps @0))
2186 (with {
2187 tree x;
2188 switch (exps)
2189 {
2190 CASE_FLT_FN (BUILT_IN_EXP):
2191 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
2192 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2193 dconst_e ()));
2194 break;
2195 CASE_FLT_FN (BUILT_IN_EXP2):
2196 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
2197 x = build_real (type, dconst2);
2198 break;
2199 CASE_FLT_FN (BUILT_IN_EXP10):
2200 CASE_FLT_FN (BUILT_IN_POW10):
2201 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
2202 {
2203 REAL_VALUE_TYPE dconst10;
2204 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
2205 x = build_real (type, dconst10);
2206 }
2207 break;
2208 default:
2209 gcc_unreachable ();
2210 }
2211 }
2212 (mult (logs { x; }) @0))))
2213 (for logs (LOG LOG
2214 LOG2 LOG2
2215 LOG10 LOG10)
2216 exps (SQRT CBRT)
2217 (simplify
2218 (logs (exps @0))
2219 (with {
2220 tree x;
2221 switch (exps)
2222 {
2223 CASE_FLT_FN (BUILT_IN_SQRT):
2224 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
2225 x = build_real (type, dconsthalf);
2226 break;
2227 CASE_FLT_FN (BUILT_IN_CBRT):
2228 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
2229 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2230 dconst_third ()));
2231 break;
2232 default:
2233 gcc_unreachable ();
2234 }
2235 }
2236 (mult { x; } (logs @0)))))
2237 /* logN(pow(x,exponent) -> exponent*logN(x). */
2238 (for logs (LOG LOG2 LOG10)
2239 pows (POW)
2240 (simplify
2241 (logs (pows @0 @1))
2242 (mult @1 (logs @0)))))
2243
2244 /* Narrowing of arithmetic and logical operations.
2245
2246 These are conceptually similar to the transformations performed for
2247 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
2248 term we want to move all that code out of the front-ends into here. */
2249
2250 /* If we have a narrowing conversion of an arithmetic operation where
2251 both operands are widening conversions from the same type as the outer
2252 narrowing conversion. Then convert the innermost operands to a suitable
2253 unsigned type (to avoid introducing undefined behaviour), perform the
2254 operation and convert the result to the desired type. */
2255 (for op (plus minus)
2256 (simplify
2257 (convert (op:s (convert@2 @0) (convert@3 @1)))
2258 (if (INTEGRAL_TYPE_P (type)
2259 /* We check for type compatibility between @0 and @1 below,
2260 so there's no need to check that @1/@3 are integral types. */
2261 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2262 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2263 /* The precision of the type of each operand must match the
2264 precision of the mode of each operand, similarly for the
2265 result. */
2266 && (TYPE_PRECISION (TREE_TYPE (@0))
2267 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2268 && (TYPE_PRECISION (TREE_TYPE (@1))
2269 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2270 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2271 /* The inner conversion must be a widening conversion. */
2272 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2273 && types_match (@0, @1)
2274 && types_match (@0, type))
2275 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2276 (convert (op @0 @1))
2277 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2278 (convert (op (convert:utype @0) (convert:utype @1))))))))
2279
2280 /* This is another case of narrowing, specifically when there's an outer
2281 BIT_AND_EXPR which masks off bits outside the type of the innermost
2282 operands. Like the previous case we have to convert the operands
2283 to unsigned types to avoid introducing undefined behaviour for the
2284 arithmetic operation. */
2285 (for op (minus plus)
2286 (simplify
2287 (bit_and (op:s (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
2288 (if (INTEGRAL_TYPE_P (type)
2289 /* We check for type compatibility between @0 and @1 below,
2290 so there's no need to check that @1/@3 are integral types. */
2291 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2292 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2293 /* The precision of the type of each operand must match the
2294 precision of the mode of each operand, similarly for the
2295 result. */
2296 && (TYPE_PRECISION (TREE_TYPE (@0))
2297 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2298 && (TYPE_PRECISION (TREE_TYPE (@1))
2299 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2300 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2301 /* The inner conversion must be a widening conversion. */
2302 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2303 && types_match (@0, @1)
2304 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
2305 <= TYPE_PRECISION (TREE_TYPE (@0)))
2306 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
2307 || tree_int_cst_sgn (@4) >= 0))
2308 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2309 (with { tree ntype = TREE_TYPE (@0); }
2310 (convert (bit_and (op @0 @1) (convert:ntype @4))))
2311 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2312 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
2313 (convert:utype @4))))))))