re PR tree-optimization/16107 (missed optimization with some math function builtins)
[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 CONSTANT_CLASS_P
32 tree_expr_nonnegative_p
33 integer_pow2p
34 HONOR_NANS)
35
36 /* Operator lists. */
37 (define_operator_list tcc_comparison
38 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
39 (define_operator_list inverted_tcc_comparison
40 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
41 (define_operator_list inverted_tcc_comparison_with_nans
42 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
43 (define_operator_list swapped_tcc_comparison
44 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
45 (define_operator_list simple_comparison lt le eq ne ge gt)
46 (define_operator_list swapped_simple_comparison gt ge eq ne le lt)
47
48 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
49 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
50 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
51 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
52 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
53 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
54 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
55 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
56 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
57 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
58 (define_operator_list COS BUILT_IN_COS BUILT_IN_COSL BUILT_IN_COSF)
59 (define_operator_list COSH BUILT_IN_COSH BUILT_IN_COSHL BUILT_IN_COSHF)
60
61
62 /* Simplifications of operations with one constant operand and
63 simplifications to constants or single values. */
64
65 (for op (plus pointer_plus minus bit_ior bit_xor)
66 (simplify
67 (op @0 integer_zerop)
68 (non_lvalue @0)))
69
70 /* 0 +p index -> (type)index */
71 (simplify
72 (pointer_plus integer_zerop @1)
73 (non_lvalue (convert @1)))
74
75 /* See if ARG1 is zero and X + ARG1 reduces to X.
76 Likewise if the operands are reversed. */
77 (simplify
78 (plus:c @0 real_zerop@1)
79 (if (fold_real_zero_addition_p (type, @1, 0))
80 (non_lvalue @0)))
81
82 /* See if ARG1 is zero and X - ARG1 reduces to X. */
83 (simplify
84 (minus @0 real_zerop@1)
85 (if (fold_real_zero_addition_p (type, @1, 1))
86 (non_lvalue @0)))
87
88 /* Simplify x - x.
89 This is unsafe for certain floats even in non-IEEE formats.
90 In IEEE, it is unsafe because it does wrong for NaNs.
91 Also note that operand_equal_p is always false if an operand
92 is volatile. */
93 (simplify
94 (minus @0 @0)
95 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
96 { build_zero_cst (type); }))
97
98 (simplify
99 (mult @0 integer_zerop@1)
100 @1)
101
102 /* Maybe fold x * 0 to 0. The expressions aren't the same
103 when x is NaN, since x * 0 is also NaN. Nor are they the
104 same in modes with signed zeros, since multiplying a
105 negative value by 0 gives -0, not +0. */
106 (simplify
107 (mult @0 real_zerop@1)
108 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (type))
109 @1))
110
111 /* In IEEE floating point, x*1 is not equivalent to x for snans.
112 Likewise for complex arithmetic with signed zeros. */
113 (simplify
114 (mult @0 real_onep)
115 (if (!HONOR_SNANS (type)
116 && (!HONOR_SIGNED_ZEROS (type)
117 || !COMPLEX_FLOAT_TYPE_P (type)))
118 (non_lvalue @0)))
119
120 /* Transform x * -1.0 into -x. */
121 (simplify
122 (mult @0 real_minus_onep)
123 (if (!HONOR_SNANS (type)
124 && (!HONOR_SIGNED_ZEROS (type)
125 || !COMPLEX_FLOAT_TYPE_P (type)))
126 (negate @0)))
127
128 /* Make sure to preserve divisions by zero. This is the reason why
129 we don't simplify x / x to 1 or 0 / x to 0. */
130 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
131 (simplify
132 (op @0 integer_onep)
133 (non_lvalue @0)))
134
135 /* X / -1 is -X. */
136 (for div (trunc_div ceil_div floor_div round_div exact_div)
137 (simplify
138 (div @0 integer_minus_onep@1)
139 (if (!TYPE_UNSIGNED (type))
140 (negate @0))))
141
142 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
143 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
144 (simplify
145 (floor_div @0 @1)
146 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
147 && TYPE_UNSIGNED (type))
148 (trunc_div @0 @1)))
149
150 /* Combine two successive divisions. Note that combining ceil_div
151 and floor_div is trickier and combining round_div even more so. */
152 (for div (trunc_div exact_div)
153 (simplify
154 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
155 (with {
156 bool overflow_p;
157 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
158 }
159 (if (!overflow_p)
160 (div @0 { wide_int_to_tree (type, mul); })
161 (if (TYPE_UNSIGNED (type)
162 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED))
163 { build_zero_cst (type); })))))
164
165 /* Optimize A / A to 1.0 if we don't care about
166 NaNs or Infinities. */
167 (simplify
168 (rdiv @0 @0)
169 (if (FLOAT_TYPE_P (type)
170 && ! HONOR_NANS (type)
171 && ! HONOR_INFINITIES (type))
172 { build_one_cst (type); }))
173
174 /* Optimize -A / A to -1.0 if we don't care about
175 NaNs or Infinities. */
176 (simplify
177 (rdiv:c @0 (negate @0))
178 (if (FLOAT_TYPE_P (type)
179 && ! HONOR_NANS (type)
180 && ! HONOR_INFINITIES (type))
181 { build_minus_one_cst (type); }))
182
183 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
184 (simplify
185 (rdiv @0 real_onep)
186 (if (!HONOR_SNANS (type))
187 (non_lvalue @0)))
188
189 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
190 (simplify
191 (rdiv @0 real_minus_onep)
192 (if (!HONOR_SNANS (type))
193 (negate @0)))
194
195 /* If ARG1 is a constant, we can convert this to a multiply by the
196 reciprocal. This does not have the same rounding properties,
197 so only do this if -freciprocal-math. We can actually
198 always safely do it if ARG1 is a power of two, but it's hard to
199 tell if it is or not in a portable manner. */
200 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
201 (simplify
202 (rdiv @0 cst@1)
203 (if (optimize)
204 (if (flag_reciprocal_math
205 && !real_zerop (@1))
206 (with
207 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
208 (if (tem)
209 (mult @0 { tem; } )))
210 (if (cst != COMPLEX_CST)
211 (with { tree inverse = exact_inverse (type, @1); }
212 (if (inverse)
213 (mult @0 { inverse; } ))))))))
214
215 /* Same applies to modulo operations, but fold is inconsistent here
216 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
217 (for mod (ceil_mod floor_mod round_mod trunc_mod)
218 /* 0 % X is always zero. */
219 (simplify
220 (mod integer_zerop@0 @1)
221 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
222 (if (!integer_zerop (@1))
223 @0))
224 /* X % 1 is always zero. */
225 (simplify
226 (mod @0 integer_onep)
227 { build_zero_cst (type); })
228 /* X % -1 is zero. */
229 (simplify
230 (mod @0 integer_minus_onep@1)
231 (if (!TYPE_UNSIGNED (type))
232 { build_zero_cst (type); }))
233 /* (X % Y) % Y is just X % Y. */
234 (simplify
235 (mod (mod@2 @0 @1) @1)
236 @2)
237 /* From extract_muldiv_1: (X * C1) % C2 is zero if C1 is a multiple of C2. */
238 (simplify
239 (mod (mult @0 INTEGER_CST@1) INTEGER_CST@2)
240 (if (ANY_INTEGRAL_TYPE_P (type)
241 && TYPE_OVERFLOW_UNDEFINED (type)
242 && wi::multiple_of_p (@1, @2, TYPE_SIGN (type)))
243 { build_zero_cst (type); })))
244
245 /* X % -C is the same as X % C. */
246 (simplify
247 (trunc_mod @0 INTEGER_CST@1)
248 (if (TYPE_SIGN (type) == SIGNED
249 && !TREE_OVERFLOW (@1)
250 && wi::neg_p (@1)
251 && !TYPE_OVERFLOW_TRAPS (type)
252 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
253 && !sign_bit_p (@1, @1))
254 (trunc_mod @0 (negate @1))))
255
256 /* X % -Y is the same as X % Y. */
257 (simplify
258 (trunc_mod @0 (convert? (negate @1)))
259 (if (!TYPE_UNSIGNED (type)
260 && !TYPE_OVERFLOW_TRAPS (type)
261 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
262 (trunc_mod @0 (convert @1))))
263
264 /* X - (X / Y) * Y is the same as X % Y. */
265 (simplify
266 (minus (convert1? @0) (convert2? (mult (trunc_div @0 @1) @1)))
267 (if (INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
268 (trunc_mod (convert @0) (convert @1))))
269
270 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
271 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
272 Also optimize A % (C << N) where C is a power of 2,
273 to A & ((C << N) - 1). */
274 (match (power_of_two_cand @1)
275 INTEGER_CST@1)
276 (match (power_of_two_cand @1)
277 (lshift INTEGER_CST@1 @2))
278 (for mod (trunc_mod floor_mod)
279 (simplify
280 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
281 (if ((TYPE_UNSIGNED (type)
282 || tree_expr_nonnegative_p (@0))
283 && tree_nop_conversion_p (type, TREE_TYPE (@3))
284 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
285 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
286
287 /* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF. */
288 (simplify
289 (trunc_div (mult @0 integer_pow2p@1) @1)
290 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
291 (bit_and @0 { wide_int_to_tree
292 (type, wi::mask (TYPE_PRECISION (type) - wi::exact_log2 (@1),
293 false, TYPE_PRECISION (type))); })))
294
295 /* Simplify (unsigned t / 2) * 2 -> unsigned t & ~1. */
296 (simplify
297 (mult (trunc_div @0 integer_pow2p@1) @1)
298 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
299 (bit_and @0 (negate @1))))
300
301 /* Simplify (t * 2) / 2) -> t. */
302 (for div (trunc_div ceil_div floor_div round_div exact_div)
303 (simplify
304 (div (mult @0 @1) @1)
305 (if (ANY_INTEGRAL_TYPE_P (type)
306 && TYPE_OVERFLOW_UNDEFINED (type))
307 @0)))
308
309 /* Simplify cos (-x) -> cos (x). */
310 (for op (negate abs)
311 (for coss (COS COSH)
312 (simplify
313 (coss (op @0))
314 (coss @0))))
315
316 /* X % Y is smaller than Y. */
317 (for cmp (lt ge)
318 (simplify
319 (cmp (trunc_mod @0 @1) @1)
320 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
321 { constant_boolean_node (cmp == LT_EXPR, type); })))
322 (for cmp (gt le)
323 (simplify
324 (cmp @1 (trunc_mod @0 @1))
325 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
326 { constant_boolean_node (cmp == GT_EXPR, type); })))
327
328 /* x | ~0 -> ~0 */
329 (simplify
330 (bit_ior @0 integer_all_onesp@1)
331 @1)
332
333 /* x & 0 -> 0 */
334 (simplify
335 (bit_and @0 integer_zerop@1)
336 @1)
337
338 /* ~x | x -> -1 */
339 /* ~x ^ x -> -1 */
340 /* ~x + x -> -1 */
341 (for op (bit_ior bit_xor plus)
342 (simplify
343 (op:c (convert? @0) (convert? (bit_not @0)))
344 (convert { build_all_ones_cst (TREE_TYPE (@0)); })))
345
346 /* x ^ x -> 0 */
347 (simplify
348 (bit_xor @0 @0)
349 { build_zero_cst (type); })
350
351 /* Canonicalize X ^ ~0 to ~X. */
352 (simplify
353 (bit_xor @0 integer_all_onesp@1)
354 (bit_not @0))
355
356 /* x & ~0 -> x */
357 (simplify
358 (bit_and @0 integer_all_onesp)
359 (non_lvalue @0))
360
361 /* x & x -> x, x | x -> x */
362 (for bitop (bit_and bit_ior)
363 (simplify
364 (bitop @0 @0)
365 (non_lvalue @0)))
366
367 /* x + (x & 1) -> (x + 1) & ~1 */
368 (simplify
369 (plus:c @0 (bit_and:s @0 integer_onep@1))
370 (bit_and (plus @0 @1) (bit_not @1)))
371
372 /* x & ~(x & y) -> x & ~y */
373 /* x | ~(x | y) -> x | ~y */
374 (for bitop (bit_and bit_ior)
375 (simplify
376 (bitop:c @0 (bit_not (bitop:cs @0 @1)))
377 (bitop @0 (bit_not @1))))
378
379 /* (x | y) & ~x -> y & ~x */
380 /* (x & y) | ~x -> y | ~x */
381 (for bitop (bit_and bit_ior)
382 rbitop (bit_ior bit_and)
383 (simplify
384 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
385 (bitop @1 @2)))
386
387 /* (x & y) ^ (x | y) -> x ^ y */
388 (simplify
389 (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
390 (bit_xor @0 @1))
391
392 /* (x ^ y) ^ (x | y) -> x & y */
393 (simplify
394 (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
395 (bit_and @0 @1))
396
397 /* (x & y) + (x ^ y) -> x | y */
398 /* (x & y) | (x ^ y) -> x | y */
399 /* (x & y) ^ (x ^ y) -> x | y */
400 (for op (plus bit_ior bit_xor)
401 (simplify
402 (op:c (bit_and @0 @1) (bit_xor @0 @1))
403 (bit_ior @0 @1)))
404
405 /* (x & y) + (x | y) -> x + y */
406 (simplify
407 (plus:c (bit_and @0 @1) (bit_ior @0 @1))
408 (plus @0 @1))
409
410 /* (x + y) - (x | y) -> x & y */
411 (simplify
412 (minus (plus @0 @1) (bit_ior @0 @1))
413 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
414 && !TYPE_SATURATING (type))
415 (bit_and @0 @1)))
416
417 /* (x + y) - (x & y) -> x | y */
418 (simplify
419 (minus (plus @0 @1) (bit_and @0 @1))
420 (if (!TYPE_OVERFLOW_SANITIZED (type) && !TYPE_OVERFLOW_TRAPS (type)
421 && !TYPE_SATURATING (type))
422 (bit_ior @0 @1)))
423
424 /* (x | y) - (x ^ y) -> x & y */
425 (simplify
426 (minus (bit_ior @0 @1) (bit_xor @0 @1))
427 (bit_and @0 @1))
428
429 /* (x | y) - (x & y) -> x ^ y */
430 (simplify
431 (minus (bit_ior @0 @1) (bit_and @0 @1))
432 (bit_xor @0 @1))
433
434 /* (x | y) & ~(x & y) -> x ^ y */
435 (simplify
436 (bit_and:c (bit_ior @0 @1) (bit_not (bit_and @0 @1)))
437 (bit_xor @0 @1))
438
439 /* (x | y) & (~x ^ y) -> x & y */
440 (simplify
441 (bit_and:c (bit_ior:c @0 @1) (bit_xor:c @1 (bit_not @0)))
442 (bit_and @0 @1))
443
444 /* ~x & ~y -> ~(x | y)
445 ~x | ~y -> ~(x & y) */
446 (for op (bit_and bit_ior)
447 rop (bit_ior bit_and)
448 (simplify
449 (op (convert1? (bit_not @0)) (convert2? (bit_not @1)))
450 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
451 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
452 (bit_not (rop (convert @0) (convert @1))))))
453
454 /* If we are XORing or adding two BIT_AND_EXPR's, both of which are and'ing
455 with a constant, and the two constants have no bits in common,
456 we should treat this as a BIT_IOR_EXPR since this may produce more
457 simplifications. */
458 (for op (bit_xor plus)
459 (simplify
460 (op (convert1? (bit_and@4 @0 INTEGER_CST@1))
461 (convert2? (bit_and@5 @2 INTEGER_CST@3)))
462 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
463 && tree_nop_conversion_p (type, TREE_TYPE (@2))
464 && wi::bit_and (@1, @3) == 0)
465 (bit_ior (convert @4) (convert @5)))))
466
467 /* (X | Y) ^ X -> Y & ~ X*/
468 (simplify
469 (bit_xor:c (convert? (bit_ior:c @0 @1)) (convert? @0))
470 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
471 (convert (bit_and @1 (bit_not @0)))))
472
473 /* Convert ~X ^ ~Y to X ^ Y. */
474 (simplify
475 (bit_xor (convert1? (bit_not @0)) (convert2? (bit_not @1)))
476 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
477 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
478 (bit_xor (convert @0) (convert @1))))
479
480 /* Convert ~X ^ C to X ^ ~C. */
481 (simplify
482 (bit_xor (convert? (bit_not @0)) INTEGER_CST@1)
483 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
484 (bit_xor (convert @0) (bit_not @1))))
485
486 /* Fold (X & Y) ^ Y as ~X & Y. */
487 (simplify
488 (bit_xor:c (bit_and:c @0 @1) @1)
489 (bit_and (bit_not @0) @1))
490
491 /* Given a bit-wise operation CODE applied to ARG0 and ARG1, see if both
492 operands are another bit-wise operation with a common input. If so,
493 distribute the bit operations to save an operation and possibly two if
494 constants are involved. For example, convert
495 (A | B) & (A | C) into A | (B & C)
496 Further simplification will occur if B and C are constants. */
497 (for op (bit_and bit_ior)
498 rop (bit_ior bit_and)
499 (simplify
500 (op (convert? (rop:c @0 @1)) (convert? (rop @0 @2)))
501 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
502 (rop (convert @0) (op (convert @1) (convert @2))))))
503
504
505 (simplify
506 (abs (abs@1 @0))
507 @1)
508 (simplify
509 (abs (negate @0))
510 (abs @0))
511 (simplify
512 (abs tree_expr_nonnegative_p@0)
513 @0)
514
515 /* A few cases of fold-const.c negate_expr_p predicate. */
516 (match negate_expr_p
517 INTEGER_CST
518 (if ((INTEGRAL_TYPE_P (type)
519 && TYPE_OVERFLOW_WRAPS (type))
520 || (!TYPE_OVERFLOW_SANITIZED (type)
521 && may_negate_without_overflow_p (t)))))
522 (match negate_expr_p
523 FIXED_CST)
524 (match negate_expr_p
525 (negate @0)
526 (if (!TYPE_OVERFLOW_SANITIZED (type))))
527 (match negate_expr_p
528 REAL_CST
529 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (t)))))
530 /* VECTOR_CST handling of non-wrapping types would recurse in unsupported
531 ways. */
532 (match negate_expr_p
533 VECTOR_CST
534 (if (FLOAT_TYPE_P (TREE_TYPE (type)) || TYPE_OVERFLOW_WRAPS (type))))
535
536 /* -(A + B) -> (-B) - A. */
537 (simplify
538 (negate (plus:c @0 negate_expr_p@1))
539 (if (!HONOR_SIGN_DEPENDENT_ROUNDING (element_mode (type))
540 && !HONOR_SIGNED_ZEROS (element_mode (type)))
541 (minus (negate @1) @0)))
542
543 /* A - B -> A + (-B) if B is easily negatable. */
544 (simplify
545 (minus @0 negate_expr_p@1)
546 (if (!FIXED_POINT_TYPE_P (type))
547 (plus @0 (negate @1))))
548
549 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
550 when profitable.
551 For bitwise binary operations apply operand conversions to the
552 binary operation result instead of to the operands. This allows
553 to combine successive conversions and bitwise binary operations.
554 We combine the above two cases by using a conditional convert. */
555 (for bitop (bit_and bit_ior bit_xor)
556 (simplify
557 (bitop (convert @0) (convert? @1))
558 (if (((TREE_CODE (@1) == INTEGER_CST
559 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
560 && int_fits_type_p (@1, TREE_TYPE (@0)))
561 || types_match (@0, @1))
562 /* ??? This transform conflicts with fold-const.c doing
563 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
564 constants (if x has signed type, the sign bit cannot be set
565 in c). This folds extension into the BIT_AND_EXPR.
566 Restrict it to GIMPLE to avoid endless recursions. */
567 && (bitop != BIT_AND_EXPR || GIMPLE)
568 && (/* That's a good idea if the conversion widens the operand, thus
569 after hoisting the conversion the operation will be narrower. */
570 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
571 /* It's also a good idea if the conversion is to a non-integer
572 mode. */
573 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
574 /* Or if the precision of TO is not the same as the precision
575 of its mode. */
576 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
577 (convert (bitop @0 (convert @1))))))
578
579 (for bitop (bit_and bit_ior)
580 rbitop (bit_ior bit_and)
581 /* (x | y) & x -> x */
582 /* (x & y) | x -> x */
583 (simplify
584 (bitop:c (rbitop:c @0 @1) @0)
585 @0)
586 /* (~x | y) & x -> x & y */
587 /* (~x & y) | x -> x | y */
588 (simplify
589 (bitop:c (rbitop:c (bit_not @0) @1) @0)
590 (bitop @0 @1)))
591
592 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
593 (for bitop (bit_and bit_ior bit_xor)
594 (simplify
595 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
596 (bit_and (bitop @0 @2) @1)))
597
598 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
599 (simplify
600 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
601 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
602
603 /* Combine successive equal operations with constants. */
604 (for bitop (bit_and bit_ior bit_xor)
605 (simplify
606 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
607 (bitop @0 (bitop @1 @2))))
608
609 /* Try simple folding for X op !X, and X op X with the help
610 of the truth_valued_p and logical_inverted_value predicates. */
611 (match truth_valued_p
612 @0
613 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
614 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
615 (match truth_valued_p
616 (op @0 @1)))
617 (match truth_valued_p
618 (truth_not @0))
619
620 (match (logical_inverted_value @0)
621 (bit_not truth_valued_p@0))
622 (match (logical_inverted_value @0)
623 (eq @0 integer_zerop))
624 (match (logical_inverted_value @0)
625 (ne truth_valued_p@0 integer_truep))
626 (match (logical_inverted_value @0)
627 (bit_xor truth_valued_p@0 integer_truep))
628
629 /* X & !X -> 0. */
630 (simplify
631 (bit_and:c @0 (logical_inverted_value @0))
632 { build_zero_cst (type); })
633 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
634 (for op (bit_ior bit_xor)
635 (simplify
636 (op:c truth_valued_p@0 (logical_inverted_value @0))
637 { constant_boolean_node (true, type); }))
638 /* X ==/!= !X is false/true. */
639 (for op (eq ne)
640 (simplify
641 (op:c truth_valued_p@0 (logical_inverted_value @0))
642 { constant_boolean_node (op == NE_EXPR ? true : false, type); }))
643
644 /* If arg1 and arg2 are booleans (or any single bit type)
645 then try to simplify:
646
647 (~X & Y) -> X < Y
648 (X & ~Y) -> Y < X
649 (~X | Y) -> X <= Y
650 (X | ~Y) -> Y <= X
651
652 But only do this if our result feeds into a comparison as
653 this transformation is not always a win, particularly on
654 targets with and-not instructions.
655 -> simplify_bitwise_binary_boolean */
656 (simplify
657 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
658 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
659 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
660 (lt @0 @1)))
661 (simplify
662 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
663 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
664 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
665 (le @0 @1)))
666
667 /* ~~x -> x */
668 (simplify
669 (bit_not (bit_not @0))
670 @0)
671
672 /* Convert ~ (-A) to A - 1. */
673 (simplify
674 (bit_not (convert? (negate @0)))
675 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
676 (convert (minus @0 { build_each_one_cst (TREE_TYPE (@0)); }))))
677
678 /* Convert ~ (A - 1) or ~ (A + -1) to -A. */
679 (simplify
680 (bit_not (convert? (minus @0 integer_each_onep)))
681 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
682 (convert (negate @0))))
683 (simplify
684 (bit_not (convert? (plus @0 integer_all_onesp)))
685 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
686 (convert (negate @0))))
687
688 /* Part of convert ~(X ^ Y) to ~X ^ Y or X ^ ~Y if ~X or ~Y simplify. */
689 (simplify
690 (bit_not (convert? (bit_xor @0 INTEGER_CST@1)))
691 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
692 (convert (bit_xor @0 (bit_not @1)))))
693 (simplify
694 (bit_not (convert? (bit_xor:c (bit_not @0) @1)))
695 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
696 (convert (bit_xor @0 @1))))
697
698 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
699 (simplify
700 (bit_ior:c (bit_and:cs @0 (bit_not @2)) (bit_and:cs @1 @2))
701 (bit_xor (bit_and (bit_xor @0 @1) @2) @0))
702
703 /* Fold A - (A & B) into ~B & A. */
704 (simplify
705 (minus (convert? @0) (convert?:s (bit_and:cs @0 @1)))
706 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
707 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
708 (convert (bit_and (bit_not @1) @0))))
709
710 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
711 (simplify
712 (pointer_plus (pointer_plus:s @0 @1) @3)
713 (pointer_plus @0 (plus @1 @3)))
714
715 /* Pattern match
716 tem1 = (long) ptr1;
717 tem2 = (long) ptr2;
718 tem3 = tem2 - tem1;
719 tem4 = (unsigned long) tem3;
720 tem5 = ptr1 + tem4;
721 and produce
722 tem5 = ptr2; */
723 (simplify
724 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
725 /* Conditionally look through a sign-changing conversion. */
726 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
727 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
728 || (GENERIC && type == TREE_TYPE (@1))))
729 @1))
730
731 /* Pattern match
732 tem = (sizetype) ptr;
733 tem = tem & algn;
734 tem = -tem;
735 ... = ptr p+ tem;
736 and produce the simpler and easier to analyze with respect to alignment
737 ... = ptr & ~algn; */
738 (simplify
739 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
740 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
741 (bit_and @0 { algn; })))
742
743 /* Try folding difference of addresses. */
744 (simplify
745 (minus (convert ADDR_EXPR@0) (convert @1))
746 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
747 (with { HOST_WIDE_INT diff; }
748 (if (ptr_difference_const (@0, @1, &diff))
749 { build_int_cst_type (type, diff); }))))
750 (simplify
751 (minus (convert @0) (convert ADDR_EXPR@1))
752 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
753 (with { HOST_WIDE_INT diff; }
754 (if (ptr_difference_const (@0, @1, &diff))
755 { build_int_cst_type (type, diff); }))))
756
757 /* If arg0 is derived from the address of an object or function, we may
758 be able to fold this expression using the object or function's
759 alignment. */
760 (simplify
761 (bit_and (convert? @0) INTEGER_CST@1)
762 (if (POINTER_TYPE_P (TREE_TYPE (@0))
763 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
764 (with
765 {
766 unsigned int align;
767 unsigned HOST_WIDE_INT bitpos;
768 get_pointer_alignment_1 (@0, &align, &bitpos);
769 }
770 (if (wi::ltu_p (@1, align / BITS_PER_UNIT))
771 { wide_int_to_tree (type, wi::bit_and (@1, bitpos / BITS_PER_UNIT)); }))))
772
773
774 /* We can't reassociate at all for saturating types. */
775 (if (!TYPE_SATURATING (type))
776
777 /* Contract negates. */
778 /* A + (-B) -> A - B */
779 (simplify
780 (plus:c (convert1? @0) (convert2? (negate @1)))
781 /* Apply STRIP_NOPS on @0 and the negate. */
782 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
783 && tree_nop_conversion_p (type, TREE_TYPE (@1))
784 && !TYPE_OVERFLOW_SANITIZED (type))
785 (minus (convert @0) (convert @1))))
786 /* A - (-B) -> A + B */
787 (simplify
788 (minus (convert1? @0) (convert2? (negate @1)))
789 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
790 && tree_nop_conversion_p (type, TREE_TYPE (@1))
791 && !TYPE_OVERFLOW_SANITIZED (type))
792 (plus (convert @0) (convert @1))))
793 /* -(-A) -> A */
794 (simplify
795 (negate (convert? (negate @1)))
796 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
797 && !TYPE_OVERFLOW_SANITIZED (type))
798 (convert @1)))
799
800 /* We can't reassociate floating-point unless -fassociative-math
801 or fixed-point plus or minus because of saturation to +-Inf. */
802 (if ((!FLOAT_TYPE_P (type) || flag_associative_math)
803 && !FIXED_POINT_TYPE_P (type))
804
805 /* Match patterns that allow contracting a plus-minus pair
806 irrespective of overflow issues. */
807 /* (A +- B) - A -> +- B */
808 /* (A +- B) -+ B -> A */
809 /* A - (A +- B) -> -+ B */
810 /* A +- (B -+ A) -> +- B */
811 (simplify
812 (minus (plus:c @0 @1) @0)
813 @1)
814 (simplify
815 (minus (minus @0 @1) @0)
816 (negate @1))
817 (simplify
818 (plus:c (minus @0 @1) @1)
819 @0)
820 (simplify
821 (minus @0 (plus:c @0 @1))
822 (negate @1))
823 (simplify
824 (minus @0 (minus @0 @1))
825 @1)
826
827 /* (A +- CST) +- CST -> A + CST */
828 (for outer_op (plus minus)
829 (for inner_op (plus minus)
830 (simplify
831 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
832 /* If the constant operation overflows we cannot do the transform
833 as we would introduce undefined overflow, for example
834 with (a - 1) + INT_MIN. */
835 (with { tree cst = fold_binary (outer_op == inner_op
836 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
837 (if (cst && !TREE_OVERFLOW (cst))
838 (inner_op @0 { cst; } ))))))
839
840 /* (CST - A) +- CST -> CST - A */
841 (for outer_op (plus minus)
842 (simplify
843 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
844 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
845 (if (cst && !TREE_OVERFLOW (cst))
846 (minus { cst; } @0)))))
847
848 /* ~A + A -> -1 */
849 (simplify
850 (plus:c (bit_not @0) @0)
851 (if (!TYPE_OVERFLOW_TRAPS (type))
852 { build_all_ones_cst (type); }))
853
854 /* ~A + 1 -> -A */
855 (simplify
856 (plus (convert? (bit_not @0)) integer_each_onep)
857 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
858 (negate (convert @0))))
859
860 /* -A - 1 -> ~A */
861 (simplify
862 (minus (convert? (negate @0)) integer_each_onep)
863 (if (!TYPE_OVERFLOW_TRAPS (type)
864 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
865 (bit_not (convert @0))))
866
867 /* -1 - A -> ~A */
868 (simplify
869 (minus integer_all_onesp @0)
870 (bit_not @0))
871
872 /* (T)(P + A) - (T)P -> (T) A */
873 (for add (plus pointer_plus)
874 (simplify
875 (minus (convert (add @0 @1))
876 (convert @0))
877 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
878 /* For integer types, if A has a smaller type
879 than T the result depends on the possible
880 overflow in P + A.
881 E.g. T=size_t, A=(unsigned)429497295, P>0.
882 However, if an overflow in P + A would cause
883 undefined behavior, we can assume that there
884 is no overflow. */
885 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
886 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
887 /* For pointer types, if the conversion of A to the
888 final type requires a sign- or zero-extension,
889 then we have to punt - it is not defined which
890 one is correct. */
891 || (POINTER_TYPE_P (TREE_TYPE (@0))
892 && TREE_CODE (@1) == INTEGER_CST
893 && tree_int_cst_sign_bit (@1) == 0))
894 (convert @1))))))
895
896
897 /* Simplifications of MIN_EXPR and MAX_EXPR. */
898
899 (for minmax (min max)
900 (simplify
901 (minmax @0 @0)
902 @0))
903 (simplify
904 (min @0 @1)
905 (if (INTEGRAL_TYPE_P (type)
906 && TYPE_MIN_VALUE (type)
907 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
908 @1))
909 (simplify
910 (max @0 @1)
911 (if (INTEGRAL_TYPE_P (type)
912 && TYPE_MAX_VALUE (type)
913 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
914 @1))
915
916
917 /* Simplifications of shift and rotates. */
918
919 (for rotate (lrotate rrotate)
920 (simplify
921 (rotate integer_all_onesp@0 @1)
922 @0))
923
924 /* Optimize -1 >> x for arithmetic right shifts. */
925 (simplify
926 (rshift integer_all_onesp@0 @1)
927 (if (!TYPE_UNSIGNED (type)
928 && tree_expr_nonnegative_p (@1))
929 @0))
930
931 (for shiftrotate (lrotate rrotate lshift rshift)
932 (simplify
933 (shiftrotate @0 integer_zerop)
934 (non_lvalue @0))
935 (simplify
936 (shiftrotate integer_zerop@0 @1)
937 @0)
938 /* Prefer vector1 << scalar to vector1 << vector2
939 if vector2 is uniform. */
940 (for vec (VECTOR_CST CONSTRUCTOR)
941 (simplify
942 (shiftrotate @0 vec@1)
943 (with { tree tem = uniform_vector_p (@1); }
944 (if (tem)
945 (shiftrotate @0 { tem; }))))))
946
947 /* Rewrite an LROTATE_EXPR by a constant into an
948 RROTATE_EXPR by a new constant. */
949 (simplify
950 (lrotate @0 INTEGER_CST@1)
951 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
952 build_int_cst (TREE_TYPE (@1),
953 element_precision (type)), @1); }))
954
955 /* Turn (a OP c1) OP c2 into a OP (c1+c2). */
956 (for op (lrotate rrotate rshift lshift)
957 (simplify
958 (op (op @0 INTEGER_CST@1) INTEGER_CST@2)
959 (with { unsigned int prec = element_precision (type); }
960 (if (wi::ge_p (@1, 0, TYPE_SIGN (TREE_TYPE (@1)))
961 && wi::lt_p (@1, prec, TYPE_SIGN (TREE_TYPE (@1)))
962 && wi::ge_p (@2, 0, TYPE_SIGN (TREE_TYPE (@2)))
963 && wi::lt_p (@2, prec, TYPE_SIGN (TREE_TYPE (@2))))
964 (with { unsigned int low = wi::add (@1, @2).to_uhwi (); }
965 /* Deal with a OP (c1 + c2) being undefined but (a OP c1) OP c2
966 being well defined. */
967 (if (low >= prec)
968 (if (op == LROTATE_EXPR || op == RROTATE_EXPR)
969 (op @0 { build_int_cst (TREE_TYPE (@1), low % prec); })
970 (if (TYPE_UNSIGNED (type) || op == LSHIFT_EXPR)
971 { build_zero_cst (type); }
972 (op @0 { build_int_cst (TREE_TYPE (@1), prec - 1); })))
973 (op @0 { build_int_cst (TREE_TYPE (@1), low); })))))))
974
975
976 /* ((1 << A) & 1) != 0 -> A == 0
977 ((1 << A) & 1) == 0 -> A != 0 */
978 (for cmp (ne eq)
979 icmp (eq ne)
980 (simplify
981 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
982 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
983
984 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
985 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
986 if CST2 != 0. */
987 (for cmp (ne eq)
988 (simplify
989 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
990 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
991 (if (cand < 0
992 || (!integer_zerop (@2)
993 && wi::ne_p (wi::lshift (@0, cand), @2)))
994 { constant_boolean_node (cmp == NE_EXPR, type); }
995 (if (!integer_zerop (@2)
996 && wi::eq_p (wi::lshift (@0, cand), @2))
997 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); }))))))
998
999 /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
1000 (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
1001 if the new mask might be further optimized. */
1002 (for shift (lshift rshift)
1003 (simplify
1004 (bit_and (convert?:s@4 (shift:s@5 (convert1?@3 @0) INTEGER_CST@1))
1005 INTEGER_CST@2)
1006 (if (tree_nop_conversion_p (TREE_TYPE (@4), TREE_TYPE (@5))
1007 && TYPE_PRECISION (type) <= HOST_BITS_PER_WIDE_INT
1008 && tree_fits_uhwi_p (@1)
1009 && tree_to_uhwi (@1) > 0
1010 && tree_to_uhwi (@1) < TYPE_PRECISION (type))
1011 (with
1012 {
1013 unsigned int shiftc = tree_to_uhwi (@1);
1014 unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (@2);
1015 unsigned HOST_WIDE_INT newmask, zerobits = 0;
1016 tree shift_type = TREE_TYPE (@3);
1017 unsigned int prec;
1018
1019 if (shift == LSHIFT_EXPR)
1020 zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1);
1021 else if (shift == RSHIFT_EXPR
1022 && (TYPE_PRECISION (shift_type)
1023 == GET_MODE_PRECISION (TYPE_MODE (shift_type))))
1024 {
1025 prec = TYPE_PRECISION (TREE_TYPE (@3));
1026 tree arg00 = @0;
1027 /* See if more bits can be proven as zero because of
1028 zero extension. */
1029 if (@3 != @0
1030 && TYPE_UNSIGNED (TREE_TYPE (@0)))
1031 {
1032 tree inner_type = TREE_TYPE (@0);
1033 if ((TYPE_PRECISION (inner_type)
1034 == GET_MODE_PRECISION (TYPE_MODE (inner_type)))
1035 && TYPE_PRECISION (inner_type) < prec)
1036 {
1037 prec = TYPE_PRECISION (inner_type);
1038 /* See if we can shorten the right shift. */
1039 if (shiftc < prec)
1040 shift_type = inner_type;
1041 /* Otherwise X >> C1 is all zeros, so we'll optimize
1042 it into (X, 0) later on by making sure zerobits
1043 is all ones. */
1044 }
1045 }
1046 zerobits = ~(unsigned HOST_WIDE_INT) 0;
1047 if (shiftc < prec)
1048 {
1049 zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc;
1050 zerobits <<= prec - shiftc;
1051 }
1052 /* For arithmetic shift if sign bit could be set, zerobits
1053 can contain actually sign bits, so no transformation is
1054 possible, unless MASK masks them all away. In that
1055 case the shift needs to be converted into logical shift. */
1056 if (!TYPE_UNSIGNED (TREE_TYPE (@3))
1057 && prec == TYPE_PRECISION (TREE_TYPE (@3)))
1058 {
1059 if ((mask & zerobits) == 0)
1060 shift_type = unsigned_type_for (TREE_TYPE (@3));
1061 else
1062 zerobits = 0;
1063 }
1064 }
1065 }
1066 /* ((X << 16) & 0xff00) is (X, 0). */
1067 (if ((mask & zerobits) == mask)
1068 { build_int_cst (type, 0); }
1069 (with { newmask = mask | zerobits; }
1070 (if (newmask != mask && (newmask & (newmask + 1)) == 0)
1071 (with
1072 {
1073 /* Only do the transformation if NEWMASK is some integer
1074 mode's mask. */
1075 for (prec = BITS_PER_UNIT;
1076 prec < HOST_BITS_PER_WIDE_INT; prec <<= 1)
1077 if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1)
1078 break;
1079 }
1080 (if (prec < HOST_BITS_PER_WIDE_INT
1081 || newmask == ~(unsigned HOST_WIDE_INT) 0)
1082 (with
1083 { tree newmaskt = build_int_cst_type (TREE_TYPE (@2), newmask); }
1084 (if (!tree_int_cst_equal (newmaskt, @2))
1085 (if (shift_type != TREE_TYPE (@3))
1086 (bit_and (convert (shift:shift_type (convert @3) @1)) { newmaskt; })
1087 (bit_and @4 { newmaskt; })))))))))))))
1088
1089 /* Fold (X & C2) << C1 into (X << C1) & (C2 << C1)
1090 (X & C2) >> C1 into (X >> C1) & (C2 >> C1). */
1091 (for shift (lshift rshift)
1092 (simplify
1093 (shift (convert?:s (bit_and:s @0 INTEGER_CST@2)) INTEGER_CST@1)
1094 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
1095 (with { tree mask = int_const_binop (shift, fold_convert (type, @2), @1); }
1096 (bit_and (shift (convert @0) @1) { mask; })))))
1097
1098
1099 /* Simplifications of conversions. */
1100
1101 /* Basic strip-useless-type-conversions / strip_nops. */
1102 (for cvt (convert view_convert float fix_trunc)
1103 (simplify
1104 (cvt @0)
1105 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
1106 || (GENERIC && type == TREE_TYPE (@0)))
1107 @0)))
1108
1109 /* Contract view-conversions. */
1110 (simplify
1111 (view_convert (view_convert @0))
1112 (view_convert @0))
1113
1114 /* For integral conversions with the same precision or pointer
1115 conversions use a NOP_EXPR instead. */
1116 (simplify
1117 (view_convert @0)
1118 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
1119 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1120 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
1121 (convert @0)))
1122
1123 /* Strip inner integral conversions that do not change precision or size. */
1124 (simplify
1125 (view_convert (convert@0 @1))
1126 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
1127 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1128 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
1129 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
1130 (view_convert @1)))
1131
1132 /* Re-association barriers around constants and other re-association
1133 barriers can be removed. */
1134 (simplify
1135 (paren CONSTANT_CLASS_P@0)
1136 @0)
1137 (simplify
1138 (paren (paren@1 @0))
1139 @1)
1140
1141 /* Handle cases of two conversions in a row. */
1142 (for ocvt (convert float fix_trunc)
1143 (for icvt (convert float)
1144 (simplify
1145 (ocvt (icvt@1 @0))
1146 (with
1147 {
1148 tree inside_type = TREE_TYPE (@0);
1149 tree inter_type = TREE_TYPE (@1);
1150 int inside_int = INTEGRAL_TYPE_P (inside_type);
1151 int inside_ptr = POINTER_TYPE_P (inside_type);
1152 int inside_float = FLOAT_TYPE_P (inside_type);
1153 int inside_vec = VECTOR_TYPE_P (inside_type);
1154 unsigned int inside_prec = TYPE_PRECISION (inside_type);
1155 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
1156 int inter_int = INTEGRAL_TYPE_P (inter_type);
1157 int inter_ptr = POINTER_TYPE_P (inter_type);
1158 int inter_float = FLOAT_TYPE_P (inter_type);
1159 int inter_vec = VECTOR_TYPE_P (inter_type);
1160 unsigned int inter_prec = TYPE_PRECISION (inter_type);
1161 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
1162 int final_int = INTEGRAL_TYPE_P (type);
1163 int final_ptr = POINTER_TYPE_P (type);
1164 int final_float = FLOAT_TYPE_P (type);
1165 int final_vec = VECTOR_TYPE_P (type);
1166 unsigned int final_prec = TYPE_PRECISION (type);
1167 int final_unsignedp = TYPE_UNSIGNED (type);
1168 }
1169 (switch
1170 /* In addition to the cases of two conversions in a row
1171 handled below, if we are converting something to its own
1172 type via an object of identical or wider precision, neither
1173 conversion is needed. */
1174 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
1175 || (GENERIC
1176 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
1177 && (((inter_int || inter_ptr) && final_int)
1178 || (inter_float && final_float))
1179 && inter_prec >= final_prec)
1180 (ocvt @0))
1181
1182 /* Likewise, if the intermediate and initial types are either both
1183 float or both integer, we don't need the middle conversion if the
1184 former is wider than the latter and doesn't change the signedness
1185 (for integers). Avoid this if the final type is a pointer since
1186 then we sometimes need the middle conversion. Likewise if the
1187 final type has a precision not equal to the size of its mode. */
1188 (if (((inter_int && inside_int) || (inter_float && inside_float))
1189 && (final_int || final_float)
1190 && inter_prec >= inside_prec
1191 && (inter_float || inter_unsignedp == inside_unsignedp)
1192 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1193 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1194 (ocvt @0))
1195
1196 /* If we have a sign-extension of a zero-extended value, we can
1197 replace that by a single zero-extension. Likewise if the
1198 final conversion does not change precision we can drop the
1199 intermediate conversion. */
1200 (if (inside_int && inter_int && final_int
1201 && ((inside_prec < inter_prec && inter_prec < final_prec
1202 && inside_unsignedp && !inter_unsignedp)
1203 || final_prec == inter_prec))
1204 (ocvt @0))
1205
1206 /* Two conversions in a row are not needed unless:
1207 - some conversion is floating-point (overstrict for now), or
1208 - some conversion is a vector (overstrict for now), or
1209 - the intermediate type is narrower than both initial and
1210 final, or
1211 - the intermediate type and innermost type differ in signedness,
1212 and the outermost type is wider than the intermediate, or
1213 - the initial type is a pointer type and the precisions of the
1214 intermediate and final types differ, or
1215 - the final type is a pointer type and the precisions of the
1216 initial and intermediate types differ. */
1217 (if (! inside_float && ! inter_float && ! final_float
1218 && ! inside_vec && ! inter_vec && ! final_vec
1219 && (inter_prec >= inside_prec || inter_prec >= final_prec)
1220 && ! (inside_int && inter_int
1221 && inter_unsignedp != inside_unsignedp
1222 && inter_prec < final_prec)
1223 && ((inter_unsignedp && inter_prec > inside_prec)
1224 == (final_unsignedp && final_prec > inter_prec))
1225 && ! (inside_ptr && inter_prec != final_prec)
1226 && ! (final_ptr && inside_prec != inter_prec)
1227 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
1228 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
1229 (ocvt @0))
1230
1231 /* A truncation to an unsigned type (a zero-extension) should be
1232 canonicalized as bitwise and of a mask. */
1233 (if (final_int && inter_int && inside_int
1234 && final_prec == inside_prec
1235 && final_prec > inter_prec
1236 && inter_unsignedp)
1237 (convert (bit_and @0 { wide_int_to_tree
1238 (inside_type,
1239 wi::mask (inter_prec, false,
1240 TYPE_PRECISION (inside_type))); })))
1241
1242 /* If we are converting an integer to a floating-point that can
1243 represent it exactly and back to an integer, we can skip the
1244 floating-point conversion. */
1245 (if (GIMPLE /* PR66211 */
1246 && inside_int && inter_float && final_int &&
1247 (unsigned) significand_size (TYPE_MODE (inter_type))
1248 >= inside_prec - !inside_unsignedp)
1249 (convert @0)))))))
1250
1251 /* If we have a narrowing conversion to an integral type that is fed by a
1252 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
1253 masks off bits outside the final type (and nothing else). */
1254 (simplify
1255 (convert (bit_and @0 INTEGER_CST@1))
1256 (if (INTEGRAL_TYPE_P (type)
1257 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1258 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
1259 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
1260 TYPE_PRECISION (type)), 0))
1261 (convert @0)))
1262
1263
1264 /* (X /[ex] A) * A -> X. */
1265 (simplify
1266 (mult (convert? (exact_div @0 @1)) @1)
1267 /* Look through a sign-changing conversion. */
1268 (convert @0))
1269
1270 /* Canonicalization of binary operations. */
1271
1272 /* Convert X + -C into X - C. */
1273 (simplify
1274 (plus @0 REAL_CST@1)
1275 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1276 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
1277 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
1278 (minus @0 { tem; })))))
1279
1280 /* Convert x+x into x*2.0. */
1281 (simplify
1282 (plus @0 @0)
1283 (if (SCALAR_FLOAT_TYPE_P (type))
1284 (mult @0 { build_real (type, dconst2); })))
1285
1286 (simplify
1287 (minus integer_zerop @1)
1288 (negate @1))
1289
1290 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
1291 ARG0 is zero and X + ARG0 reduces to X, since that would mean
1292 (-ARG1 + ARG0) reduces to -ARG1. */
1293 (simplify
1294 (minus real_zerop@0 @1)
1295 (if (fold_real_zero_addition_p (type, @0, 0))
1296 (negate @1)))
1297
1298 /* Transform x * -1 into -x. */
1299 (simplify
1300 (mult @0 integer_minus_onep)
1301 (negate @0))
1302
1303 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
1304 (simplify
1305 (complex (realpart @0) (imagpart @0))
1306 @0)
1307 (simplify
1308 (realpart (complex @0 @1))
1309 @0)
1310 (simplify
1311 (imagpart (complex @0 @1))
1312 @1)
1313
1314
1315 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
1316 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
1317 (simplify
1318 (bswap (bswap @0))
1319 @0)
1320 (simplify
1321 (bswap (bit_not (bswap @0)))
1322 (bit_not @0))
1323 (for bitop (bit_xor bit_ior bit_and)
1324 (simplify
1325 (bswap (bitop:c (bswap @0) @1))
1326 (bitop @0 (bswap @1)))))
1327
1328
1329 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
1330
1331 /* Simplify constant conditions.
1332 Only optimize constant conditions when the selected branch
1333 has the same type as the COND_EXPR. This avoids optimizing
1334 away "c ? x : throw", where the throw has a void type.
1335 Note that we cannot throw away the fold-const.c variant nor
1336 this one as we depend on doing this transform before possibly
1337 A ? B : B -> B triggers and the fold-const.c one can optimize
1338 0 ? A : B to B even if A has side-effects. Something
1339 genmatch cannot handle. */
1340 (simplify
1341 (cond INTEGER_CST@0 @1 @2)
1342 (if (integer_zerop (@0))
1343 (if (!VOID_TYPE_P (TREE_TYPE (@2)) || VOID_TYPE_P (type))
1344 @2)
1345 (if (!VOID_TYPE_P (TREE_TYPE (@1)) || VOID_TYPE_P (type))
1346 @1)))
1347 (simplify
1348 (vec_cond VECTOR_CST@0 @1 @2)
1349 (if (integer_all_onesp (@0))
1350 @1
1351 (if (integer_zerop (@0))
1352 @2)))
1353
1354 (for cnd (cond vec_cond)
1355 /* A ? B : (A ? X : C) -> A ? B : C. */
1356 (simplify
1357 (cnd @0 (cnd @0 @1 @2) @3)
1358 (cnd @0 @1 @3))
1359 (simplify
1360 (cnd @0 @1 (cnd @0 @2 @3))
1361 (cnd @0 @1 @3))
1362
1363 /* A ? B : B -> B. */
1364 (simplify
1365 (cnd @0 @1 @1)
1366 @1)
1367
1368 /* !A ? B : C -> A ? C : B. */
1369 (simplify
1370 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
1371 (cnd @0 @2 @1)))
1372
1373 /* A + (B vcmp C ? 1 : 0) -> A - (B vcmp C), since vector comparisons
1374 return all-1 or all-0 results. */
1375 /* ??? We could instead convert all instances of the vec_cond to negate,
1376 but that isn't necessarily a win on its own. */
1377 (simplify
1378 (plus:c @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1379 (if (VECTOR_TYPE_P (type)
1380 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1381 && (TYPE_MODE (TREE_TYPE (type))
1382 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1383 (minus @3 (view_convert @0))))
1384
1385 /* ... likewise A - (B vcmp C ? 1 : 0) -> A + (B vcmp C). */
1386 (simplify
1387 (minus @3 (view_convert? (vec_cond @0 integer_each_onep@1 integer_zerop@2)))
1388 (if (VECTOR_TYPE_P (type)
1389 && TYPE_VECTOR_SUBPARTS (type) == TYPE_VECTOR_SUBPARTS (TREE_TYPE (@0))
1390 && (TYPE_MODE (TREE_TYPE (type))
1391 == TYPE_MODE (TREE_TYPE (TREE_TYPE (@0)))))
1392 (plus @3 (view_convert @0))))
1393
1394
1395 /* Simplifications of comparisons. */
1396
1397 /* See if we can reduce the magnitude of a constant involved in a
1398 comparison by changing the comparison code. This is a canonicalization
1399 formerly done by maybe_canonicalize_comparison_1. */
1400 (for cmp (le gt)
1401 acmp (lt ge)
1402 (simplify
1403 (cmp @0 INTEGER_CST@1)
1404 (if (tree_int_cst_sgn (@1) == -1)
1405 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1406 (for cmp (ge lt)
1407 acmp (gt le)
1408 (simplify
1409 (cmp @0 INTEGER_CST@1)
1410 (if (tree_int_cst_sgn (@1) == 1)
1411 (acmp @0 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1412
1413
1414 /* We can simplify a logical negation of a comparison to the
1415 inverted comparison. As we cannot compute an expression
1416 operator using invert_tree_comparison we have to simulate
1417 that with expression code iteration. */
1418 (for cmp (tcc_comparison)
1419 icmp (inverted_tcc_comparison)
1420 ncmp (inverted_tcc_comparison_with_nans)
1421 /* Ideally we'd like to combine the following two patterns
1422 and handle some more cases by using
1423 (logical_inverted_value (cmp @0 @1))
1424 here but for that genmatch would need to "inline" that.
1425 For now implement what forward_propagate_comparison did. */
1426 (simplify
1427 (bit_not (cmp @0 @1))
1428 (if (VECTOR_TYPE_P (type)
1429 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
1430 /* Comparison inversion may be impossible for trapping math,
1431 invert_tree_comparison will tell us. But we can't use
1432 a computed operator in the replacement tree thus we have
1433 to play the trick below. */
1434 (with { enum tree_code ic = invert_tree_comparison
1435 (cmp, HONOR_NANS (@0)); }
1436 (if (ic == icmp)
1437 (icmp @0 @1)
1438 (if (ic == ncmp)
1439 (ncmp @0 @1))))))
1440 (simplify
1441 (bit_xor (cmp @0 @1) integer_truep)
1442 (with { enum tree_code ic = invert_tree_comparison
1443 (cmp, HONOR_NANS (@0)); }
1444 (if (ic == icmp)
1445 (icmp @0 @1)
1446 (if (ic == ncmp)
1447 (ncmp @0 @1))))))
1448
1449 /* Transform comparisons of the form X - Y CMP 0 to X CMP Y.
1450 ??? The transformation is valid for the other operators if overflow
1451 is undefined for the type, but performing it here badly interacts
1452 with the transformation in fold_cond_expr_with_comparison which
1453 attempts to synthetize ABS_EXPR. */
1454 (for cmp (eq ne)
1455 (simplify
1456 (cmp (minus@2 @0 @1) integer_zerop)
1457 (if (single_use (@2))
1458 (cmp @0 @1))))
1459
1460 /* Transform comparisons of the form X * C1 CMP 0 to X CMP 0 in the
1461 signed arithmetic case. That form is created by the compiler
1462 often enough for folding it to be of value. One example is in
1463 computing loop trip counts after Operator Strength Reduction. */
1464 (for cmp (simple_comparison)
1465 scmp (swapped_simple_comparison)
1466 (simplify
1467 (cmp (mult @0 INTEGER_CST@1) integer_zerop@2)
1468 /* Handle unfolded multiplication by zero. */
1469 (if (integer_zerop (@1))
1470 (cmp @1 @2)
1471 (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1472 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
1473 /* If @1 is negative we swap the sense of the comparison. */
1474 (if (tree_int_cst_sgn (@1) < 0)
1475 (scmp @0 @2)
1476 (cmp @0 @2))))))
1477
1478 /* Simplify comparison of something with itself. For IEEE
1479 floating-point, we can only do some of these simplifications. */
1480 (simplify
1481 (eq @0 @0)
1482 (if (! FLOAT_TYPE_P (TREE_TYPE (@0))
1483 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1484 { constant_boolean_node (true, type); }))
1485 (for cmp (ge le)
1486 (simplify
1487 (cmp @0 @0)
1488 (eq @0 @0)))
1489 (for cmp (ne gt lt)
1490 (simplify
1491 (cmp @0 @0)
1492 (if (cmp != NE_EXPR
1493 || ! FLOAT_TYPE_P (TREE_TYPE (@0))
1494 || ! HONOR_NANS (TYPE_MODE (TREE_TYPE (@0))))
1495 { constant_boolean_node (false, type); })))
1496 (for cmp (unle unge uneq)
1497 (simplify
1498 (cmp @0 @0)
1499 { constant_boolean_node (true, type); }))
1500 (simplify
1501 (ltgt @0 @0)
1502 (if (!flag_trapping_math)
1503 { constant_boolean_node (false, type); }))
1504
1505 /* Fold ~X op ~Y as Y op X. */
1506 (for cmp (simple_comparison)
1507 (simplify
1508 (cmp (bit_not @0) (bit_not @1))
1509 (cmp @1 @0)))
1510
1511 /* Fold ~X op C as X op' ~C, where op' is the swapped comparison. */
1512 (for cmp (simple_comparison)
1513 scmp (swapped_simple_comparison)
1514 (simplify
1515 (cmp (bit_not @0) CONSTANT_CLASS_P@1)
1516 (if (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST)
1517 (scmp @0 (bit_not @1)))))
1518
1519 (for cmp (simple_comparison)
1520 /* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
1521 (simplify
1522 (cmp (convert@2 @0) (convert? @1))
1523 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1524 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1525 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@0)))
1526 && (DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@2))
1527 == DECIMAL_FLOAT_TYPE_P (TREE_TYPE (@1))))
1528 (with
1529 {
1530 tree type1 = TREE_TYPE (@1);
1531 if (TREE_CODE (@1) == REAL_CST && !DECIMAL_FLOAT_TYPE_P (type1))
1532 {
1533 REAL_VALUE_TYPE orig = TREE_REAL_CST (@1);
1534 if (TYPE_PRECISION (type1) > TYPE_PRECISION (float_type_node)
1535 && exact_real_truncate (TYPE_MODE (float_type_node), &orig))
1536 type1 = float_type_node;
1537 if (TYPE_PRECISION (type1) > TYPE_PRECISION (double_type_node)
1538 && exact_real_truncate (TYPE_MODE (double_type_node), &orig))
1539 type1 = double_type_node;
1540 }
1541 tree newtype
1542 = (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (type1)
1543 ? TREE_TYPE (@0) : type1);
1544 }
1545 (if (TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (newtype))
1546 (cmp (convert:newtype @0) (convert:newtype @1))))))
1547
1548 (simplify
1549 (cmp @0 REAL_CST@1)
1550 /* IEEE doesn't distinguish +0 and -0 in comparisons. */
1551 (switch
1552 /* a CMP (-0) -> a CMP 0 */
1553 (if (REAL_VALUE_MINUS_ZERO (TREE_REAL_CST (@1)))
1554 (cmp @0 { build_real (TREE_TYPE (@1), dconst0); }))
1555 /* x != NaN is always true, other ops are always false. */
1556 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1557 && ! HONOR_SNANS (@1))
1558 { constant_boolean_node (cmp == NE_EXPR, type); })
1559 /* Fold comparisons against infinity. */
1560 (if (REAL_VALUE_ISINF (TREE_REAL_CST (@1))
1561 && MODE_HAS_INFINITIES (TYPE_MODE (TREE_TYPE (@1))))
1562 (with
1563 {
1564 REAL_VALUE_TYPE max;
1565 enum tree_code code = cmp;
1566 bool neg = REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1));
1567 if (neg)
1568 code = swap_tree_comparison (code);
1569 }
1570 (switch
1571 /* x > +Inf is always false, if with ignore sNANs. */
1572 (if (code == GT_EXPR
1573 && ! HONOR_SNANS (@0))
1574 { constant_boolean_node (false, type); })
1575 (if (code == LE_EXPR)
1576 /* x <= +Inf is always true, if we don't case about NaNs. */
1577 (if (! HONOR_NANS (@0))
1578 { constant_boolean_node (true, type); }
1579 /* x <= +Inf is the same as x == x, i.e. isfinite(x). */
1580 (eq @0 @0)))
1581 /* x == +Inf and x >= +Inf are always equal to x > DBL_MAX. */
1582 (if (code == EQ_EXPR || code == GE_EXPR)
1583 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1584 (if (neg)
1585 (lt @0 { build_real (TREE_TYPE (@0), max); })
1586 (gt @0 { build_real (TREE_TYPE (@0), max); }))))
1587 /* x < +Inf is always equal to x <= DBL_MAX. */
1588 (if (code == LT_EXPR)
1589 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1590 (if (neg)
1591 (ge @0 { build_real (TREE_TYPE (@0), max); })
1592 (le @0 { build_real (TREE_TYPE (@0), max); }))))
1593 /* x != +Inf is always equal to !(x > DBL_MAX). */
1594 (if (code == NE_EXPR)
1595 (with { real_maxval (&max, neg, TYPE_MODE (TREE_TYPE (@0))); }
1596 (if (! HONOR_NANS (@0))
1597 (if (neg)
1598 (ge @0 { build_real (TREE_TYPE (@0), max); })
1599 (le @0 { build_real (TREE_TYPE (@0), max); }))
1600 (if (neg)
1601 (bit_xor (lt @0 { build_real (TREE_TYPE (@0), max); })
1602 { build_one_cst (type); })
1603 (bit_xor (gt @0 { build_real (TREE_TYPE (@0), max); })
1604 { build_one_cst (type); }))))))))))
1605
1606 /* If this is a comparison of a real constant with a PLUS_EXPR
1607 or a MINUS_EXPR of a real constant, we can convert it into a
1608 comparison with a revised real constant as long as no overflow
1609 occurs when unsafe_math_optimizations are enabled. */
1610 (if (flag_unsafe_math_optimizations)
1611 (for op (plus minus)
1612 (simplify
1613 (cmp (op @0 REAL_CST@1) REAL_CST@2)
1614 (with
1615 {
1616 tree tem = const_binop (op == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR,
1617 TREE_TYPE (@1), @2, @1);
1618 }
1619 (if (tem && !TREE_OVERFLOW (tem))
1620 (cmp @0 { tem; }))))))
1621
1622 /* Likewise, we can simplify a comparison of a real constant with
1623 a MINUS_EXPR whose first operand is also a real constant, i.e.
1624 (c1 - x) < c2 becomes x > c1-c2. Reordering is allowed on
1625 floating-point types only if -fassociative-math is set. */
1626 (if (flag_associative_math)
1627 (simplify
1628 (cmp (minus REAL_CST@0 @1) REAL_CST@2)
1629 (with { tree tem = const_binop (MINUS_EXPR, TREE_TYPE (@1), @0, @2); }
1630 (if (tem && !TREE_OVERFLOW (tem))
1631 (cmp { tem; } @1)))))
1632
1633 /* Fold comparisons against built-in math functions. */
1634 (if (flag_unsafe_math_optimizations
1635 && ! flag_errno_math)
1636 (for sq (SQRT)
1637 (simplify
1638 (cmp (sq @0) REAL_CST@1)
1639 (switch
1640 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
1641 (switch
1642 /* sqrt(x) < y is always false, if y is negative. */
1643 (if (cmp == EQ_EXPR || cmp == LT_EXPR || cmp == LE_EXPR)
1644 { constant_boolean_node (false, type); })
1645 /* sqrt(x) > y is always true, if y is negative and we
1646 don't care about NaNs, i.e. negative values of x. */
1647 (if (cmp == NE_EXPR || !HONOR_NANS (@0))
1648 { constant_boolean_node (true, type); })
1649 /* sqrt(x) > y is the same as x >= 0, if y is negative. */
1650 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })))
1651 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1652 (with
1653 {
1654 REAL_VALUE_TYPE c2;
1655 REAL_ARITHMETIC (c2, MULT_EXPR,
1656 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1657 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1658 }
1659 (if (REAL_VALUE_ISINF (c2))
1660 /* sqrt(x) > y is x == +Inf, when y is very large. */
1661 (if (HONOR_INFINITIES (@0))
1662 (eq @0 { build_real (TREE_TYPE (@0), c2); })
1663 { constant_boolean_node (false, type); })
1664 /* sqrt(x) > c is the same as x > c*c. */
1665 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))
1666 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1667 (with
1668 {
1669 REAL_VALUE_TYPE c2;
1670 REAL_ARITHMETIC (c2, MULT_EXPR,
1671 TREE_REAL_CST (@1), TREE_REAL_CST (@1));
1672 real_convert (&c2, TYPE_MODE (TREE_TYPE (@0)), &c2);
1673 }
1674 (if (REAL_VALUE_ISINF (c2))
1675 (switch
1676 /* sqrt(x) < y is always true, when y is a very large
1677 value and we don't care about NaNs or Infinities. */
1678 (if (! HONOR_NANS (@0) && ! HONOR_INFINITIES (@0))
1679 { constant_boolean_node (true, type); })
1680 /* sqrt(x) < y is x != +Inf when y is very large and we
1681 don't care about NaNs. */
1682 (if (! HONOR_NANS (@0))
1683 (ne @0 { build_real (TREE_TYPE (@0), c2); }))
1684 /* sqrt(x) < y is x >= 0 when y is very large and we
1685 don't care about Infinities. */
1686 (if (! HONOR_INFINITIES (@0))
1687 (ge @0 { build_real (TREE_TYPE (@0), dconst0); }))
1688 /* sqrt(x) < y is x >= 0 && x != +Inf, when y is large. */
1689 (if (GENERIC)
1690 (truth_andif
1691 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1692 (ne @0 { build_real (TREE_TYPE (@0), c2); }))))
1693 /* sqrt(x) < c is the same as x < c*c, if we ignore NaNs. */
1694 (if (! HONOR_NANS (@0))
1695 (cmp @0 { build_real (TREE_TYPE (@0), c2); })
1696 /* sqrt(x) < c is the same as x >= 0 && x < c*c. */
1697 (if (GENERIC)
1698 (truth_andif
1699 (ge @0 { build_real (TREE_TYPE (@0), dconst0); })
1700 (cmp @0 { build_real (TREE_TYPE (@0), c2); }))))))))))))
1701
1702 /* Unordered tests if either argument is a NaN. */
1703 (simplify
1704 (bit_ior (unordered @0 @0) (unordered @1 @1))
1705 (if (types_match (@0, @1))
1706 (unordered @0 @1)))
1707 (simplify
1708 (bit_and (ordered @0 @0) (ordered @1 @1))
1709 (if (types_match (@0, @1))
1710 (ordered @0 @1)))
1711 (simplify
1712 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1713 @2)
1714 (simplify
1715 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1716 @2)
1717
1718 /* -A CMP -B -> B CMP A. */
1719 (for cmp (tcc_comparison)
1720 scmp (swapped_tcc_comparison)
1721 (simplify
1722 (cmp (negate @0) (negate @1))
1723 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1724 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1725 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1726 (scmp @0 @1)))
1727 (simplify
1728 (cmp (negate @0) CONSTANT_CLASS_P@1)
1729 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1730 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1731 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1732 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1733 (if (tem && !TREE_OVERFLOW (tem))
1734 (scmp @0 { tem; }))))))
1735
1736 /* From fold_sign_changed_comparison and fold_widened_comparison. */
1737 (for cmp (simple_comparison)
1738 (simplify
1739 (cmp (convert@0 @00) (convert?@1 @10))
1740 (if (TREE_CODE (TREE_TYPE (@0)) == INTEGER_TYPE
1741 /* Disable this optimization if we're casting a function pointer
1742 type on targets that require function pointer canonicalization. */
1743 && !(targetm.have_canonicalize_funcptr_for_compare ()
1744 && TREE_CODE (TREE_TYPE (@00)) == POINTER_TYPE
1745 && TREE_CODE (TREE_TYPE (TREE_TYPE (@00))) == FUNCTION_TYPE)
1746 && single_use (@0))
1747 (if (TYPE_PRECISION (TREE_TYPE (@00)) == TYPE_PRECISION (TREE_TYPE (@0))
1748 && (TREE_CODE (@10) == INTEGER_CST
1749 || (@1 != @10 && types_match (TREE_TYPE (@10), TREE_TYPE (@00))))
1750 && (TYPE_UNSIGNED (TREE_TYPE (@00)) == TYPE_UNSIGNED (TREE_TYPE (@0))
1751 || cmp == NE_EXPR
1752 || cmp == EQ_EXPR)
1753 && (POINTER_TYPE_P (TREE_TYPE (@00)) == POINTER_TYPE_P (TREE_TYPE (@0))))
1754 /* ??? The special-casing of INTEGER_CST conversion was in the original
1755 code and here to avoid a spurious overflow flag on the resulting
1756 constant which fold_convert produces. */
1757 (if (TREE_CODE (@1) == INTEGER_CST)
1758 (cmp @00 { force_fit_type (TREE_TYPE (@00), wi::to_widest (@1), 0,
1759 TREE_OVERFLOW (@1)); })
1760 (cmp @00 (convert @1)))
1761
1762 (if (TYPE_PRECISION (TREE_TYPE (@0)) > TYPE_PRECISION (TREE_TYPE (@00)))
1763 /* If possible, express the comparison in the shorter mode. */
1764 (if ((cmp == EQ_EXPR || cmp == NE_EXPR
1765 || TYPE_UNSIGNED (TREE_TYPE (@0)) == TYPE_UNSIGNED (TREE_TYPE (@00)))
1766 && (types_match (TREE_TYPE (@10), TREE_TYPE (@00))
1767 || ((TYPE_PRECISION (TREE_TYPE (@00))
1768 >= TYPE_PRECISION (TREE_TYPE (@10)))
1769 && (TYPE_UNSIGNED (TREE_TYPE (@00))
1770 == TYPE_UNSIGNED (TREE_TYPE (@10))))
1771 || (TREE_CODE (@10) == INTEGER_CST
1772 && (TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1773 || TREE_CODE (TREE_TYPE (@00)) == BOOLEAN_TYPE)
1774 && int_fits_type_p (@10, TREE_TYPE (@00)))))
1775 (cmp @00 (convert @10))
1776 (if (TREE_CODE (@10) == INTEGER_CST
1777 && TREE_CODE (TREE_TYPE (@00)) == INTEGER_TYPE
1778 && !int_fits_type_p (@10, TREE_TYPE (@00)))
1779 (with
1780 {
1781 tree min = lower_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1782 tree max = upper_bound_in_type (TREE_TYPE (@10), TREE_TYPE (@00));
1783 bool above = integer_nonzerop (const_binop (LT_EXPR, type, max, @10));
1784 bool below = integer_nonzerop (const_binop (LT_EXPR, type, @10, min));
1785 }
1786 (if (above || below)
1787 (if (cmp == EQ_EXPR || cmp == NE_EXPR)
1788 { constant_boolean_node (cmp == EQ_EXPR ? false : true, type); }
1789 (if (cmp == LT_EXPR || cmp == LE_EXPR)
1790 { constant_boolean_node (above ? true : false, type); }
1791 (if (cmp == GT_EXPR || cmp == GE_EXPR)
1792 { constant_boolean_node (above ? false : true, type); }))))))))))))
1793
1794 (for cmp (eq ne)
1795 /* A local variable can never be pointed to by
1796 the default SSA name of an incoming parameter.
1797 SSA names are canonicalized to 2nd place. */
1798 (simplify
1799 (cmp addr@0 SSA_NAME@1)
1800 (if (SSA_NAME_IS_DEFAULT_DEF (@1)
1801 && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL)
1802 (with { tree base = get_base_address (TREE_OPERAND (@0, 0)); }
1803 (if (TREE_CODE (base) == VAR_DECL
1804 && auto_var_in_fn_p (base, current_function_decl))
1805 (if (cmp == NE_EXPR)
1806 { constant_boolean_node (true, type); }
1807 { constant_boolean_node (false, type); }))))))
1808
1809 /* Equality compare simplifications from fold_binary */
1810 (for cmp (eq ne)
1811
1812 /* If we have (A | C) == D where C & ~D != 0, convert this into 0.
1813 Similarly for NE_EXPR. */
1814 (simplify
1815 (cmp (convert?@3 (bit_ior @0 INTEGER_CST@1)) INTEGER_CST@2)
1816 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0))
1817 && wi::bit_and_not (@1, @2) != 0)
1818 { constant_boolean_node (cmp == NE_EXPR, type); }))
1819
1820 /* (X ^ Y) == 0 becomes X == Y, and (X ^ Y) != 0 becomes X != Y. */
1821 (simplify
1822 (cmp (bit_xor @0 @1) integer_zerop)
1823 (cmp @0 @1))
1824
1825 /* (X ^ Y) == Y becomes X == 0.
1826 Likewise (X ^ Y) == X becomes Y == 0. */
1827 (simplify
1828 (cmp:c (bit_xor:c @0 @1) @0)
1829 (cmp @1 { build_zero_cst (TREE_TYPE (@1)); }))
1830
1831 /* (X ^ C1) op C2 can be rewritten as X op (C1 ^ C2). */
1832 (simplify
1833 (cmp (convert?@3 (bit_xor @0 INTEGER_CST@1)) INTEGER_CST@2)
1834 (if (tree_nop_conversion_p (TREE_TYPE (@3), TREE_TYPE (@0)))
1835 (cmp @0 (bit_xor @1 (convert @2)))))
1836
1837 (simplify
1838 (cmp (convert? addr@0) integer_zerop)
1839 (if (tree_single_nonzero_warnv_p (@0, NULL))
1840 { constant_boolean_node (cmp == NE_EXPR, type); })))
1841
1842 /* When the addresses are not directly of decls compare base and offset.
1843 This implements some remaining parts of fold_comparison address
1844 comparisons but still no complete part of it. Still it is good
1845 enough to make fold_stmt not regress when not dispatching to fold_binary. */
1846 (for cmp (simple_comparison)
1847 (simplify
1848 (cmp (convert1?@2 addr@0) (convert2? addr@1))
1849 (with
1850 {
1851 HOST_WIDE_INT off0, off1;
1852 tree base0 = get_addr_base_and_unit_offset (TREE_OPERAND (@0, 0), &off0);
1853 tree base1 = get_addr_base_and_unit_offset (TREE_OPERAND (@1, 0), &off1);
1854 if (base0 && TREE_CODE (base0) == MEM_REF)
1855 {
1856 off0 += mem_ref_offset (base0).to_short_addr ();
1857 base0 = TREE_OPERAND (base0, 0);
1858 }
1859 if (base1 && TREE_CODE (base1) == MEM_REF)
1860 {
1861 off1 += mem_ref_offset (base1).to_short_addr ();
1862 base1 = TREE_OPERAND (base1, 0);
1863 }
1864 }
1865 (if (base0 && base1)
1866 (with
1867 {
1868 int equal = 2;
1869 if (decl_in_symtab_p (base0)
1870 && decl_in_symtab_p (base1))
1871 equal = symtab_node::get_create (base0)
1872 ->equal_address_to (symtab_node::get_create (base1));
1873 else if ((DECL_P (base0) || TREE_CODE (base0) == SSA_NAME)
1874 && (DECL_P (base1) || TREE_CODE (base1) == SSA_NAME))
1875 equal = (base0 == base1);
1876 }
1877 (if (equal == 1
1878 && (cmp == EQ_EXPR || cmp == NE_EXPR
1879 /* If the offsets are equal we can ignore overflow. */
1880 || off0 == off1
1881 || POINTER_TYPE_OVERFLOW_UNDEFINED
1882 /* Or if we compare using pointers to decls. */
1883 || (POINTER_TYPE_P (TREE_TYPE (@2))
1884 && DECL_P (base0))))
1885 (switch
1886 (if (cmp == EQ_EXPR)
1887 { constant_boolean_node (off0 == off1, type); })
1888 (if (cmp == NE_EXPR)
1889 { constant_boolean_node (off0 != off1, type); })
1890 (if (cmp == LT_EXPR)
1891 { constant_boolean_node (off0 < off1, type); })
1892 (if (cmp == LE_EXPR)
1893 { constant_boolean_node (off0 <= off1, type); })
1894 (if (cmp == GE_EXPR)
1895 { constant_boolean_node (off0 >= off1, type); })
1896 (if (cmp == GT_EXPR)
1897 { constant_boolean_node (off0 > off1, type); }))
1898 (if (equal == 0
1899 && DECL_P (base0) && DECL_P (base1)
1900 /* If we compare this as integers require equal offset. */
1901 && (!INTEGRAL_TYPE_P (TREE_TYPE (@2))
1902 || off0 == off1))
1903 (switch
1904 (if (cmp == EQ_EXPR)
1905 { constant_boolean_node (false, type); })
1906 (if (cmp == NE_EXPR)
1907 { constant_boolean_node (true, type); })))))))))
1908
1909 /* Non-equality compare simplifications from fold_binary */
1910 (for cmp (lt gt le ge)
1911 /* Comparisons with the highest or lowest possible integer of
1912 the specified precision will have known values. */
1913 (simplify
1914 (cmp (convert?@2 @0) INTEGER_CST@1)
1915 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
1916 && tree_nop_conversion_p (TREE_TYPE (@2), TREE_TYPE (@0)))
1917 (with
1918 {
1919 tree arg1_type = TREE_TYPE (@1);
1920 unsigned int prec = TYPE_PRECISION (arg1_type);
1921 wide_int max = wi::max_value (arg1_type);
1922 wide_int signed_max = wi::max_value (prec, SIGNED);
1923 wide_int min = wi::min_value (arg1_type);
1924 }
1925 (switch
1926 (if (wi::eq_p (@1, max))
1927 (switch
1928 (if (cmp == GT_EXPR)
1929 { constant_boolean_node (false, type); })
1930 (if (cmp == GE_EXPR)
1931 (eq @2 @1))
1932 (if (cmp == LE_EXPR)
1933 { constant_boolean_node (true, type); })
1934 (if (cmp == LT_EXPR)
1935 (ne @2 @1))))
1936 (if (wi::eq_p (@1, min))
1937 (switch
1938 (if (cmp == LT_EXPR)
1939 { constant_boolean_node (false, type); })
1940 (if (cmp == LE_EXPR)
1941 (eq @2 @1))
1942 (if (cmp == GE_EXPR)
1943 { constant_boolean_node (true, type); })
1944 (if (cmp == GT_EXPR)
1945 (ne @2 @1))))
1946 (if (wi::eq_p (@1, max - 1))
1947 (switch
1948 (if (cmp == GT_EXPR)
1949 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))
1950 (if (cmp == LE_EXPR)
1951 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::add (@1, 1)); }))))
1952 (if (wi::eq_p (@1, min + 1))
1953 (switch
1954 (if (cmp == GE_EXPR)
1955 (ne @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))
1956 (if (cmp == LT_EXPR)
1957 (eq @2 { wide_int_to_tree (TREE_TYPE (@1), wi::sub (@1, 1)); }))))
1958 (if (wi::eq_p (@1, signed_max)
1959 && TYPE_UNSIGNED (arg1_type)
1960 /* We will flip the signedness of the comparison operator
1961 associated with the mode of @1, so the sign bit is
1962 specified by this mode. Check that @1 is the signed
1963 max associated with this sign bit. */
1964 && prec == GET_MODE_PRECISION (TYPE_MODE (arg1_type))
1965 /* signed_type does not work on pointer types. */
1966 && INTEGRAL_TYPE_P (arg1_type))
1967 /* The following case also applies to X < signed_max+1
1968 and X >= signed_max+1 because previous transformations. */
1969 (if (cmp == LE_EXPR || cmp == GT_EXPR)
1970 (with { tree st = signed_type_for (arg1_type); }
1971 (if (cmp == LE_EXPR)
1972 (ge (convert:st @0) { build_zero_cst (st); })
1973 (lt (convert:st @0) { build_zero_cst (st); }))))))))))
1974
1975 (for cmp (unordered ordered unlt unle ungt unge uneq ltgt)
1976 /* If the second operand is NaN, the result is constant. */
1977 (simplify
1978 (cmp @0 REAL_CST@1)
1979 (if (REAL_VALUE_ISNAN (TREE_REAL_CST (@1))
1980 && (cmp != LTGT_EXPR || ! flag_trapping_math))
1981 { constant_boolean_node (cmp == ORDERED_EXPR || cmp == LTGT_EXPR
1982 ? false : true, type); })))
1983
1984 /* bool_var != 0 becomes bool_var. */
1985 (simplify
1986 (ne @0 integer_zerop)
1987 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1988 && types_match (type, TREE_TYPE (@0)))
1989 (non_lvalue @0)))
1990 /* bool_var == 1 becomes bool_var. */
1991 (simplify
1992 (eq @0 integer_onep)
1993 (if (TREE_CODE (TREE_TYPE (@0)) == BOOLEAN_TYPE
1994 && types_match (type, TREE_TYPE (@0)))
1995 (non_lvalue @0)))
1996 /* Do not handle
1997 bool_var == 0 becomes !bool_var or
1998 bool_var != 1 becomes !bool_var
1999 here because that only is good in assignment context as long
2000 as we require a tcc_comparison in GIMPLE_CONDs where we'd
2001 replace if (x == 0) with tem = ~x; if (tem != 0) which is
2002 clearly less optimal and which we'll transform again in forwprop. */
2003
2004
2005 /* Simplification of math builtins. */
2006
2007 /* fold_builtin_logarithm */
2008 (if (flag_unsafe_math_optimizations)
2009 /* Special case, optimize logN(expN(x)) = x. */
2010 (for logs (LOG LOG2 LOG10)
2011 exps (EXP EXP2 EXP10)
2012 (simplify
2013 (logs (exps @0))
2014 @0))
2015 /* Optimize logN(func()) for various exponential functions. We
2016 want to determine the value "x" and the power "exponent" in
2017 order to transform logN(x**exponent) into exponent*logN(x). */
2018 (for logs (LOG LOG LOG LOG
2019 LOG2 LOG2 LOG2 LOG2
2020 LOG10 LOG10 LOG10 LOG10)
2021 exps (EXP EXP2 EXP10 POW10)
2022 (simplify
2023 (logs (exps @0))
2024 (with {
2025 tree x;
2026 switch (exps)
2027 {
2028 CASE_FLT_FN (BUILT_IN_EXP):
2029 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
2030 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2031 dconst_e ()));
2032 break;
2033 CASE_FLT_FN (BUILT_IN_EXP2):
2034 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
2035 x = build_real (type, dconst2);
2036 break;
2037 CASE_FLT_FN (BUILT_IN_EXP10):
2038 CASE_FLT_FN (BUILT_IN_POW10):
2039 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
2040 {
2041 REAL_VALUE_TYPE dconst10;
2042 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
2043 x = build_real (type, dconst10);
2044 }
2045 break;
2046 default:
2047 gcc_unreachable ();
2048 }
2049 }
2050 (mult (logs { x; }) @0))))
2051 (for logs (LOG LOG
2052 LOG2 LOG2
2053 LOG10 LOG10)
2054 exps (SQRT CBRT)
2055 (simplify
2056 (logs (exps @0))
2057 (with {
2058 tree x;
2059 switch (exps)
2060 {
2061 CASE_FLT_FN (BUILT_IN_SQRT):
2062 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
2063 x = build_real (type, dconsthalf);
2064 break;
2065 CASE_FLT_FN (BUILT_IN_CBRT):
2066 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
2067 x = build_real (type, real_value_truncate (TYPE_MODE (type),
2068 dconst_third ()));
2069 break;
2070 default:
2071 gcc_unreachable ();
2072 }
2073 }
2074 (mult { x; } (logs @0)))))
2075 /* logN(pow(x,exponent) -> exponent*logN(x). */
2076 (for logs (LOG LOG2 LOG10)
2077 pows (POW)
2078 (simplify
2079 (logs (pows @0 @1))
2080 (mult @1 (logs @0)))))
2081
2082 /* Narrowing of arithmetic and logical operations.
2083
2084 These are conceptually similar to the transformations performed for
2085 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
2086 term we want to move all that code out of the front-ends into here. */
2087
2088 /* If we have a narrowing conversion of an arithmetic operation where
2089 both operands are widening conversions from the same type as the outer
2090 narrowing conversion. Then convert the innermost operands to a suitable
2091 unsigned type (to avoid introducing undefined behaviour), perform the
2092 operation and convert the result to the desired type. */
2093 (for op (plus minus)
2094 (simplify
2095 (convert (op:s (convert@2 @0) (convert@3 @1)))
2096 (if (INTEGRAL_TYPE_P (type)
2097 /* We check for type compatibility between @0 and @1 below,
2098 so there's no need to check that @1/@3 are integral types. */
2099 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2100 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2101 /* The precision of the type of each operand must match the
2102 precision of the mode of each operand, similarly for the
2103 result. */
2104 && (TYPE_PRECISION (TREE_TYPE (@0))
2105 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2106 && (TYPE_PRECISION (TREE_TYPE (@1))
2107 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2108 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2109 /* The inner conversion must be a widening conversion. */
2110 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2111 && types_match (@0, @1)
2112 && types_match (@0, type))
2113 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2114 (convert (op @0 @1))
2115 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2116 (convert (op (convert:utype @0) (convert:utype @1))))))))
2117
2118 /* This is another case of narrowing, specifically when there's an outer
2119 BIT_AND_EXPR which masks off bits outside the type of the innermost
2120 operands. Like the previous case we have to convert the operands
2121 to unsigned types to avoid introducing undefined behaviour for the
2122 arithmetic operation. */
2123 (for op (minus plus)
2124 (simplify
2125 (bit_and (op:s (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
2126 (if (INTEGRAL_TYPE_P (type)
2127 /* We check for type compatibility between @0 and @1 below,
2128 so there's no need to check that @1/@3 are integral types. */
2129 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
2130 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
2131 /* The precision of the type of each operand must match the
2132 precision of the mode of each operand, similarly for the
2133 result. */
2134 && (TYPE_PRECISION (TREE_TYPE (@0))
2135 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
2136 && (TYPE_PRECISION (TREE_TYPE (@1))
2137 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
2138 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
2139 /* The inner conversion must be a widening conversion. */
2140 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
2141 && types_match (@0, @1)
2142 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
2143 <= TYPE_PRECISION (TREE_TYPE (@0)))
2144 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
2145 || tree_int_cst_sgn (@4) >= 0))
2146 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
2147 (with { tree ntype = TREE_TYPE (@0); }
2148 (convert (bit_and (op @0 @1) (convert:ntype @4))))
2149 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
2150 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
2151 (convert:utype @4))))))))