match.pd ((x ^ y) ^ (x | y) -> x & y, (x & y) + (x ^ y) -> x | y, (x & y) | (x ^...
[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
30 real_zerop real_onep real_minus_onep
31 CONSTANT_CLASS_P
32 tree_expr_nonnegative_p)
33
34 /* Operator lists. */
35 (define_operator_list tcc_comparison
36 lt le eq ne ge gt unordered ordered unlt unle ungt unge uneq ltgt)
37 (define_operator_list inverted_tcc_comparison
38 ge gt ne eq lt le ordered unordered ge gt le lt ltgt uneq)
39 (define_operator_list inverted_tcc_comparison_with_nans
40 unge ungt ne eq unlt unle ordered unordered ge gt le lt ltgt uneq)
41 (define_operator_list swapped_tcc_comparison
42 gt ge eq ne le lt unordered ordered ungt unge unlt unle uneq ltgt)
43
44
45 /* Simplifications of operations with one constant operand and
46 simplifications to constants or single values. */
47
48 (for op (plus pointer_plus minus bit_ior bit_xor)
49 (simplify
50 (op @0 integer_zerop)
51 (non_lvalue @0)))
52
53 /* 0 +p index -> (type)index */
54 (simplify
55 (pointer_plus integer_zerop @1)
56 (non_lvalue (convert @1)))
57
58 /* See if ARG1 is zero and X + ARG1 reduces to X.
59 Likewise if the operands are reversed. */
60 (simplify
61 (plus:c @0 real_zerop@1)
62 (if (fold_real_zero_addition_p (type, @1, 0))
63 (non_lvalue @0)))
64
65 /* See if ARG1 is zero and X - ARG1 reduces to X. */
66 (simplify
67 (minus @0 real_zerop@1)
68 (if (fold_real_zero_addition_p (type, @1, 1))
69 (non_lvalue @0)))
70
71 /* Simplify x - x.
72 This is unsafe for certain floats even in non-IEEE formats.
73 In IEEE, it is unsafe because it does wrong for NaNs.
74 Also note that operand_equal_p is always false if an operand
75 is volatile. */
76 (simplify
77 (minus @0 @0)
78 (if (!FLOAT_TYPE_P (type) || !HONOR_NANS (type))
79 { build_zero_cst (type); }))
80
81 (simplify
82 (mult @0 integer_zerop@1)
83 @1)
84
85 /* Maybe fold x * 0 to 0. The expressions aren't the same
86 when x is NaN, since x * 0 is also NaN. Nor are they the
87 same in modes with signed zeros, since multiplying a
88 negative value by 0 gives -0, not +0. */
89 (simplify
90 (mult @0 real_zerop@1)
91 (if (!HONOR_NANS (type) && !HONOR_SIGNED_ZEROS (element_mode (type)))
92 @1))
93
94 /* In IEEE floating point, x*1 is not equivalent to x for snans.
95 Likewise for complex arithmetic with signed zeros. */
96 (simplify
97 (mult @0 real_onep)
98 (if (!HONOR_SNANS (element_mode (type))
99 && (!HONOR_SIGNED_ZEROS (element_mode (type))
100 || !COMPLEX_FLOAT_TYPE_P (type)))
101 (non_lvalue @0)))
102
103 /* Transform x * -1.0 into -x. */
104 (simplify
105 (mult @0 real_minus_onep)
106 (if (!HONOR_SNANS (element_mode (type))
107 && (!HONOR_SIGNED_ZEROS (element_mode (type))
108 || !COMPLEX_FLOAT_TYPE_P (type)))
109 (negate @0)))
110
111 /* Make sure to preserve divisions by zero. This is the reason why
112 we don't simplify x / x to 1 or 0 / x to 0. */
113 (for op (mult trunc_div ceil_div floor_div round_div exact_div)
114 (simplify
115 (op @0 integer_onep)
116 (non_lvalue @0)))
117
118 /* X / -1 is -X. */
119 (for div (trunc_div ceil_div floor_div round_div exact_div)
120 (simplify
121 (div @0 integer_minus_onep@1)
122 (if (!TYPE_UNSIGNED (type))
123 (negate @0))))
124
125 /* For unsigned integral types, FLOOR_DIV_EXPR is the same as
126 TRUNC_DIV_EXPR. Rewrite into the latter in this case. */
127 (simplify
128 (floor_div @0 @1)
129 (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
130 && TYPE_UNSIGNED (type))
131 (trunc_div @0 @1)))
132
133 /* Combine two successive divisions. Note that combining ceil_div
134 and floor_div is trickier and combining round_div even more so. */
135 (for div (trunc_div exact_div)
136 (simplify
137 (div (div @0 INTEGER_CST@1) INTEGER_CST@2)
138 (with {
139 bool overflow_p;
140 wide_int mul = wi::mul (@1, @2, TYPE_SIGN (type), &overflow_p);
141 }
142 (if (!overflow_p)
143 (div @0 { wide_int_to_tree (type, mul); }))
144 (if (overflow_p
145 && (TYPE_UNSIGNED (type)
146 || mul != wi::min_value (TYPE_PRECISION (type), SIGNED)))
147 { build_zero_cst (type); }))))
148
149 /* Optimize A / A to 1.0 if we don't care about
150 NaNs or Infinities. */
151 (simplify
152 (rdiv @0 @0)
153 (if (FLOAT_TYPE_P (type)
154 && ! HONOR_NANS (type)
155 && ! HONOR_INFINITIES (element_mode (type)))
156 { build_one_cst (type); }))
157
158 /* Optimize -A / A to -1.0 if we don't care about
159 NaNs or Infinities. */
160 (simplify
161 (rdiv:c @0 (negate @0))
162 (if (FLOAT_TYPE_P (type)
163 && ! HONOR_NANS (type)
164 && ! HONOR_INFINITIES (element_mode (type)))
165 { build_minus_one_cst (type); }))
166
167 /* In IEEE floating point, x/1 is not equivalent to x for snans. */
168 (simplify
169 (rdiv @0 real_onep)
170 (if (!HONOR_SNANS (element_mode (type)))
171 (non_lvalue @0)))
172
173 /* In IEEE floating point, x/-1 is not equivalent to -x for snans. */
174 (simplify
175 (rdiv @0 real_minus_onep)
176 (if (!HONOR_SNANS (element_mode (type)))
177 (negate @0)))
178
179 /* If ARG1 is a constant, we can convert this to a multiply by the
180 reciprocal. This does not have the same rounding properties,
181 so only do this if -freciprocal-math. We can actually
182 always safely do it if ARG1 is a power of two, but it's hard to
183 tell if it is or not in a portable manner. */
184 (for cst (REAL_CST COMPLEX_CST VECTOR_CST)
185 (simplify
186 (rdiv @0 cst@1)
187 (if (optimize)
188 (if (flag_reciprocal_math
189 && !real_zerop (@1))
190 (with
191 { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
192 (if (tem)
193 (mult @0 { tem; } ))))
194 (if (cst != COMPLEX_CST)
195 (with { tree inverse = exact_inverse (type, @1); }
196 (if (inverse)
197 (mult @0 { inverse; } )))))))
198
199 /* Same applies to modulo operations, but fold is inconsistent here
200 and simplifies 0 % x to 0, only preserving literal 0 % 0. */
201 (for mod (ceil_mod floor_mod round_mod trunc_mod)
202 /* 0 % X is always zero. */
203 (simplify
204 (mod integer_zerop@0 @1)
205 /* But not for 0 % 0 so that we can get the proper warnings and errors. */
206 (if (!integer_zerop (@1))
207 @0))
208 /* X % 1 is always zero. */
209 (simplify
210 (mod @0 integer_onep)
211 { build_zero_cst (type); })
212 /* X % -1 is zero. */
213 (simplify
214 (mod @0 integer_minus_onep@1)
215 (if (!TYPE_UNSIGNED (type))
216 { build_zero_cst (type); }))
217 /* (X % Y) % Y is just X % Y. */
218 (simplify
219 (mod (mod@2 @0 @1) @1)
220 @2))
221
222 /* X % -C is the same as X % C. */
223 (simplify
224 (trunc_mod @0 INTEGER_CST@1)
225 (if (TYPE_SIGN (type) == SIGNED
226 && !TREE_OVERFLOW (@1)
227 && wi::neg_p (@1)
228 && !TYPE_OVERFLOW_TRAPS (type)
229 /* Avoid this transformation if C is INT_MIN, i.e. C == -C. */
230 && !sign_bit_p (@1, @1))
231 (trunc_mod @0 (negate @1))))
232
233 /* X % -Y is the same as X % Y. */
234 (simplify
235 (trunc_mod @0 (convert? (negate @1)))
236 (if (!TYPE_UNSIGNED (type)
237 && !TYPE_OVERFLOW_TRAPS (type)
238 && tree_nop_conversion_p (type, TREE_TYPE (@1)))
239 (trunc_mod @0 (convert @1))))
240
241 /* Optimize TRUNC_MOD_EXPR by a power of two into a BIT_AND_EXPR,
242 i.e. "X % C" into "X & (C - 1)", if X and C are positive.
243 Also optimize A % (C << N) where C is a power of 2,
244 to A & ((C << N) - 1). */
245 (match (power_of_two_cand @1)
246 INTEGER_CST@1)
247 (match (power_of_two_cand @1)
248 (lshift INTEGER_CST@1 @2))
249 (for mod (trunc_mod floor_mod)
250 (simplify
251 (mod @0 (convert?@3 (power_of_two_cand@1 @2)))
252 (if ((TYPE_UNSIGNED (type)
253 || tree_expr_nonnegative_p (@0))
254 && tree_nop_conversion_p (type, TREE_TYPE (@3))
255 && integer_pow2p (@2) && tree_int_cst_sgn (@2) > 0)
256 (bit_and @0 (convert (minus @1 { build_int_cst (TREE_TYPE (@1), 1); }))))))
257
258 /* X % Y is smaller than Y. */
259 (for cmp (lt ge)
260 (simplify
261 (cmp (trunc_mod @0 @1) @1)
262 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
263 { constant_boolean_node (cmp == LT_EXPR, type); })))
264 (for cmp (gt le)
265 (simplify
266 (cmp @1 (trunc_mod @0 @1))
267 (if (TYPE_UNSIGNED (TREE_TYPE (@0)))
268 { constant_boolean_node (cmp == GT_EXPR, type); })))
269
270 /* x | ~0 -> ~0 */
271 (simplify
272 (bit_ior @0 integer_all_onesp@1)
273 @1)
274
275 /* x & 0 -> 0 */
276 (simplify
277 (bit_and @0 integer_zerop@1)
278 @1)
279
280 /* x ^ x -> 0 */
281 (simplify
282 (bit_xor @0 @0)
283 { build_zero_cst (type); })
284
285 /* Canonicalize X ^ ~0 to ~X. */
286 (simplify
287 (bit_xor @0 integer_all_onesp@1)
288 (bit_not @0))
289
290 /* x & ~0 -> x */
291 (simplify
292 (bit_and @0 integer_all_onesp)
293 (non_lvalue @0))
294
295 /* x & x -> x, x | x -> x */
296 (for bitop (bit_and bit_ior)
297 (simplify
298 (bitop @0 @0)
299 (non_lvalue @0)))
300
301 /* x + (x & 1) -> (x + 1) & ~1 */
302 (simplify
303 (plus:c @0 (bit_and@2 @0 integer_onep@1))
304 (if (single_use (@2))
305 (bit_and (plus @0 @1) (bit_not @1))))
306
307 /* x & ~(x & y) -> x & ~y */
308 /* x | ~(x | y) -> x | ~y */
309 (for bitop (bit_and bit_ior)
310 (simplify
311 (bitop:c @0 (bit_not (bitop:c@2 @0 @1)))
312 (if (single_use (@2))
313 (bitop @0 (bit_not @1)))))
314
315 /* (x | y) & ~x -> y & ~x */
316 /* (x & y) | ~x -> y | ~x */
317 (for bitop (bit_and bit_ior)
318 rbitop (bit_ior bit_and)
319 (simplify
320 (bitop:c (rbitop:c @0 @1) (bit_not@2 @0))
321 (bitop @1 @2)))
322
323 /* (x & y) ^ (x | y) -> x ^ y */
324 (simplify
325 (bit_xor:c (bit_and @0 @1) (bit_ior @0 @1))
326 (bit_xor @0 @1))
327
328 /* (x ^ y) ^ (x | y) -> x & y */
329 (simplify
330 (bit_xor:c (bit_xor @0 @1) (bit_ior @0 @1))
331 (bit_and @0 @1))
332
333 /* (x & y) + (x ^ y) -> x | y */
334 /* (x & y) | (x ^ y) -> x | y */
335 /* (x & y) ^ (x ^ y) -> x | y */
336 (for op (plus bit_ior bit_xor)
337 (simplify
338 (op:c (bit_and @0 @1) (bit_xor @0 @1))
339 (bit_ior @0 @1)))
340
341 /* (x & y) + (x | y) -> x + y */
342 (simplify
343 (plus:c (bit_and @0 @1) (bit_ior @0 @1))
344 (plus @0 @1))
345
346 /* (x | y) - (x ^ y) -> x & y */
347 (simplify
348 (minus (bit_ior @0 @1) (bit_xor @0 @1))
349 (bit_and @0 @1))
350
351 /* (x | y) - (x & y) -> x ^ y */
352 (simplify
353 (minus (bit_ior @0 @1) (bit_and @0 @1))
354 (bit_xor @0 @1))
355
356 (simplify
357 (abs (negate @0))
358 (abs @0))
359 (simplify
360 (abs tree_expr_nonnegative_p@0)
361 @0)
362
363
364 /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST))
365 when profitable.
366 For bitwise binary operations apply operand conversions to the
367 binary operation result instead of to the operands. This allows
368 to combine successive conversions and bitwise binary operations.
369 We combine the above two cases by using a conditional convert. */
370 (for bitop (bit_and bit_ior bit_xor)
371 (simplify
372 (bitop (convert @0) (convert? @1))
373 (if (((TREE_CODE (@1) == INTEGER_CST
374 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
375 && int_fits_type_p (@1, TREE_TYPE (@0)))
376 || types_match (@0, @1))
377 /* ??? This transform conflicts with fold-const.c doing
378 Convert (T)(x & c) into (T)x & (T)c, if c is an integer
379 constants (if x has signed type, the sign bit cannot be set
380 in c). This folds extension into the BIT_AND_EXPR.
381 Restrict it to GIMPLE to avoid endless recursions. */
382 && (bitop != BIT_AND_EXPR || GIMPLE)
383 && (/* That's a good idea if the conversion widens the operand, thus
384 after hoisting the conversion the operation will be narrower. */
385 TYPE_PRECISION (TREE_TYPE (@0)) < TYPE_PRECISION (type)
386 /* It's also a good idea if the conversion is to a non-integer
387 mode. */
388 || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT
389 /* Or if the precision of TO is not the same as the precision
390 of its mode. */
391 || TYPE_PRECISION (type) != GET_MODE_PRECISION (TYPE_MODE (type))))
392 (convert (bitop @0 (convert @1))))))
393
394 /* Simplify (A & B) OP0 (C & B) to (A OP0 C) & B. */
395 (for bitop (bit_and bit_ior bit_xor)
396 (simplify
397 (bitop (bit_and:c @0 @1) (bit_and @2 @1))
398 (bit_and (bitop @0 @2) @1)))
399
400 /* (x | CST1) & CST2 -> (x & CST2) | (CST1 & CST2) */
401 (simplify
402 (bit_and (bit_ior @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
403 (bit_ior (bit_and @0 @2) (bit_and @1 @2)))
404
405 /* Combine successive equal operations with constants. */
406 (for bitop (bit_and bit_ior bit_xor)
407 (simplify
408 (bitop (bitop @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
409 (bitop @0 (bitop @1 @2))))
410
411 /* Try simple folding for X op !X, and X op X with the help
412 of the truth_valued_p and logical_inverted_value predicates. */
413 (match truth_valued_p
414 @0
415 (if (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1)))
416 (for op (tcc_comparison truth_and truth_andif truth_or truth_orif truth_xor)
417 (match truth_valued_p
418 (op @0 @1)))
419 (match truth_valued_p
420 (truth_not @0))
421
422 (match (logical_inverted_value @0)
423 (bit_not truth_valued_p@0))
424 (match (logical_inverted_value @0)
425 (eq @0 integer_zerop))
426 (match (logical_inverted_value @0)
427 (ne truth_valued_p@0 integer_truep))
428 (match (logical_inverted_value @0)
429 (bit_xor truth_valued_p@0 integer_truep))
430
431 /* X & !X -> 0. */
432 (simplify
433 (bit_and:c @0 (logical_inverted_value @0))
434 { build_zero_cst (type); })
435 /* X | !X and X ^ !X -> 1, , if X is truth-valued. */
436 (for op (bit_ior bit_xor)
437 (simplify
438 (op:c truth_valued_p@0 (logical_inverted_value @0))
439 { constant_boolean_node (true, type); }))
440
441 (for bitop (bit_and bit_ior)
442 rbitop (bit_ior bit_and)
443 /* (x | y) & x -> x */
444 /* (x & y) | x -> x */
445 (simplify
446 (bitop:c (rbitop:c @0 @1) @0)
447 @0)
448 /* (~x | y) & x -> x & y */
449 /* (~x & y) | x -> x | y */
450 (simplify
451 (bitop:c (rbitop:c (bit_not @0) @1) @0)
452 (bitop @0 @1)))
453
454 /* If arg1 and arg2 are booleans (or any single bit type)
455 then try to simplify:
456
457 (~X & Y) -> X < Y
458 (X & ~Y) -> Y < X
459 (~X | Y) -> X <= Y
460 (X | ~Y) -> Y <= X
461
462 But only do this if our result feeds into a comparison as
463 this transformation is not always a win, particularly on
464 targets with and-not instructions.
465 -> simplify_bitwise_binary_boolean */
466 (simplify
467 (ne (bit_and:c (bit_not @0) @1) integer_zerop)
468 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
469 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
470 (lt @0 @1)))
471 (simplify
472 (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
473 (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
474 && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
475 (le @0 @1)))
476
477 /* ~~x -> x */
478 (simplify
479 (bit_not (bit_not @0))
480 @0)
481
482 /* (x & ~m) | (y & m) -> ((x ^ y) & m) ^ x */
483 (simplify
484 (bit_ior:c (bit_and:c@3 @0 (bit_not @2)) (bit_and:c@4 @1 @2))
485 (if (single_use (@3) && single_use (@4))
486 (bit_xor (bit_and (bit_xor @0 @1) @2) @0)))
487
488
489 /* Associate (p +p off1) +p off2 as (p +p (off1 + off2)). */
490 (simplify
491 (pointer_plus (pointer_plus@2 @0 @1) @3)
492 (if (single_use (@2))
493 (pointer_plus @0 (plus @1 @3))))
494
495 /* Pattern match
496 tem1 = (long) ptr1;
497 tem2 = (long) ptr2;
498 tem3 = tem2 - tem1;
499 tem4 = (unsigned long) tem3;
500 tem5 = ptr1 + tem4;
501 and produce
502 tem5 = ptr2; */
503 (simplify
504 (pointer_plus @0 (convert?@2 (minus@3 (convert @1) (convert @0))))
505 /* Conditionally look through a sign-changing conversion. */
506 (if (TYPE_PRECISION (TREE_TYPE (@2)) == TYPE_PRECISION (TREE_TYPE (@3))
507 && ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@1)))
508 || (GENERIC && type == TREE_TYPE (@1))))
509 @1))
510
511 /* Pattern match
512 tem = (sizetype) ptr;
513 tem = tem & algn;
514 tem = -tem;
515 ... = ptr p+ tem;
516 and produce the simpler and easier to analyze with respect to alignment
517 ... = ptr & ~algn; */
518 (simplify
519 (pointer_plus @0 (negate (bit_and (convert @0) INTEGER_CST@1)))
520 (with { tree algn = wide_int_to_tree (TREE_TYPE (@0), wi::bit_not (@1)); }
521 (bit_and @0 { algn; })))
522
523
524 /* We can't reassociate at all for saturating types. */
525 (if (!TYPE_SATURATING (type))
526
527 /* Contract negates. */
528 /* A + (-B) -> A - B */
529 (simplify
530 (plus:c (convert1? @0) (convert2? (negate @1)))
531 /* Apply STRIP_NOPS on @0 and the negate. */
532 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
533 && tree_nop_conversion_p (type, TREE_TYPE (@1))
534 && !TYPE_OVERFLOW_SANITIZED (type))
535 (minus (convert @0) (convert @1))))
536 /* A - (-B) -> A + B */
537 (simplify
538 (minus (convert1? @0) (convert2? (negate @1)))
539 (if (tree_nop_conversion_p (type, TREE_TYPE (@0))
540 && tree_nop_conversion_p (type, TREE_TYPE (@1))
541 && !TYPE_OVERFLOW_SANITIZED (type))
542 (plus (convert @0) (convert @1))))
543 /* -(-A) -> A */
544 (simplify
545 (negate (convert? (negate @1)))
546 (if (tree_nop_conversion_p (type, TREE_TYPE (@1))
547 && !TYPE_OVERFLOW_SANITIZED (type))
548 (convert @1)))
549
550 /* We can't reassociate floating-point or fixed-point plus or minus
551 because of saturation to +-Inf. */
552 (if (!FLOAT_TYPE_P (type) && !FIXED_POINT_TYPE_P (type))
553
554 /* Match patterns that allow contracting a plus-minus pair
555 irrespective of overflow issues. */
556 /* (A +- B) - A -> +- B */
557 /* (A +- B) -+ B -> A */
558 /* A - (A +- B) -> -+ B */
559 /* A +- (B -+ A) -> +- B */
560 (simplify
561 (minus (plus:c @0 @1) @0)
562 @1)
563 (simplify
564 (minus (minus @0 @1) @0)
565 (negate @1))
566 (simplify
567 (plus:c (minus @0 @1) @1)
568 @0)
569 (simplify
570 (minus @0 (plus:c @0 @1))
571 (negate @1))
572 (simplify
573 (minus @0 (minus @0 @1))
574 @1)
575
576 /* (A +- CST) +- CST -> A + CST */
577 (for outer_op (plus minus)
578 (for inner_op (plus minus)
579 (simplify
580 (outer_op (inner_op @0 CONSTANT_CLASS_P@1) CONSTANT_CLASS_P@2)
581 /* If the constant operation overflows we cannot do the transform
582 as we would introduce undefined overflow, for example
583 with (a - 1) + INT_MIN. */
584 (with { tree cst = fold_binary (outer_op == inner_op
585 ? PLUS_EXPR : MINUS_EXPR, type, @1, @2); }
586 (if (cst && !TREE_OVERFLOW (cst))
587 (inner_op @0 { cst; } ))))))
588
589 /* (CST - A) +- CST -> CST - A */
590 (for outer_op (plus minus)
591 (simplify
592 (outer_op (minus CONSTANT_CLASS_P@1 @0) CONSTANT_CLASS_P@2)
593 (with { tree cst = fold_binary (outer_op, type, @1, @2); }
594 (if (cst && !TREE_OVERFLOW (cst))
595 (minus { cst; } @0)))))
596
597 /* ~A + A -> -1 */
598 (simplify
599 (plus:c (bit_not @0) @0)
600 (if (!TYPE_OVERFLOW_TRAPS (type))
601 { build_all_ones_cst (type); }))
602
603 /* ~A + 1 -> -A */
604 (simplify
605 (plus (convert? (bit_not @0)) integer_each_onep)
606 (if (tree_nop_conversion_p (type, TREE_TYPE (@0)))
607 (negate (convert @0))))
608
609 /* -A - 1 -> ~A */
610 (simplify
611 (minus (convert? (negate @0)) integer_each_onep)
612 (if (!TYPE_OVERFLOW_TRAPS (type)
613 && tree_nop_conversion_p (type, TREE_TYPE (@0)))
614 (bit_not (convert @0))))
615
616 /* -1 - A -> ~A */
617 (simplify
618 (minus integer_all_onesp @0)
619 (bit_not @0))
620
621 /* (T)(P + A) - (T)P -> (T) A */
622 (for add (plus pointer_plus)
623 (simplify
624 (minus (convert (add @0 @1))
625 (convert @0))
626 (if (element_precision (type) <= element_precision (TREE_TYPE (@1))
627 /* For integer types, if A has a smaller type
628 than T the result depends on the possible
629 overflow in P + A.
630 E.g. T=size_t, A=(unsigned)429497295, P>0.
631 However, if an overflow in P + A would cause
632 undefined behavior, we can assume that there
633 is no overflow. */
634 || (INTEGRAL_TYPE_P (TREE_TYPE (@0))
635 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0)))
636 /* For pointer types, if the conversion of A to the
637 final type requires a sign- or zero-extension,
638 then we have to punt - it is not defined which
639 one is correct. */
640 || (POINTER_TYPE_P (TREE_TYPE (@0))
641 && TREE_CODE (@1) == INTEGER_CST
642 && tree_int_cst_sign_bit (@1) == 0))
643 (convert @1))))))
644
645
646 /* Simplifications of MIN_EXPR and MAX_EXPR. */
647
648 (for minmax (min max)
649 (simplify
650 (minmax @0 @0)
651 @0))
652 (simplify
653 (min @0 @1)
654 (if (INTEGRAL_TYPE_P (type)
655 && TYPE_MIN_VALUE (type)
656 && operand_equal_p (@1, TYPE_MIN_VALUE (type), OEP_ONLY_CONST))
657 @1))
658 (simplify
659 (max @0 @1)
660 (if (INTEGRAL_TYPE_P (type)
661 && TYPE_MAX_VALUE (type)
662 && operand_equal_p (@1, TYPE_MAX_VALUE (type), OEP_ONLY_CONST))
663 @1))
664
665
666 /* Simplifications of shift and rotates. */
667
668 (for rotate (lrotate rrotate)
669 (simplify
670 (rotate integer_all_onesp@0 @1)
671 @0))
672
673 /* Optimize -1 >> x for arithmetic right shifts. */
674 (simplify
675 (rshift integer_all_onesp@0 @1)
676 (if (!TYPE_UNSIGNED (type)
677 && tree_expr_nonnegative_p (@1))
678 @0))
679
680 (for shiftrotate (lrotate rrotate lshift rshift)
681 (simplify
682 (shiftrotate @0 integer_zerop)
683 (non_lvalue @0))
684 (simplify
685 (shiftrotate integer_zerop@0 @1)
686 @0)
687 /* Prefer vector1 << scalar to vector1 << vector2
688 if vector2 is uniform. */
689 (for vec (VECTOR_CST CONSTRUCTOR)
690 (simplify
691 (shiftrotate @0 vec@1)
692 (with { tree tem = uniform_vector_p (@1); }
693 (if (tem)
694 (shiftrotate @0 { tem; }))))))
695
696 /* Rewrite an LROTATE_EXPR by a constant into an
697 RROTATE_EXPR by a new constant. */
698 (simplify
699 (lrotate @0 INTEGER_CST@1)
700 (rrotate @0 { fold_binary (MINUS_EXPR, TREE_TYPE (@1),
701 build_int_cst (TREE_TYPE (@1),
702 element_precision (type)), @1); }))
703
704 /* ((1 << A) & 1) != 0 -> A == 0
705 ((1 << A) & 1) == 0 -> A != 0 */
706 (for cmp (ne eq)
707 icmp (eq ne)
708 (simplify
709 (cmp (bit_and (lshift integer_onep @0) integer_onep) integer_zerop)
710 (icmp @0 { build_zero_cst (TREE_TYPE (@0)); })))
711
712 /* (CST1 << A) == CST2 -> A == ctz (CST2) - ctz (CST1)
713 (CST1 << A) != CST2 -> A != ctz (CST2) - ctz (CST1)
714 if CST2 != 0. */
715 (for cmp (ne eq)
716 (simplify
717 (cmp (lshift INTEGER_CST@0 @1) INTEGER_CST@2)
718 (with { int cand = wi::ctz (@2) - wi::ctz (@0); }
719 (if (cand < 0
720 || (!integer_zerop (@2)
721 && wi::ne_p (wi::lshift (@0, cand), @2)))
722 { constant_boolean_node (cmp == NE_EXPR, type); })
723 (if (!integer_zerop (@2)
724 && wi::eq_p (wi::lshift (@0, cand), @2))
725 (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); })))))
726
727 /* Simplifications of conversions. */
728
729 /* Basic strip-useless-type-conversions / strip_nops. */
730 (for cvt (convert view_convert float fix_trunc)
731 (simplify
732 (cvt @0)
733 (if ((GIMPLE && useless_type_conversion_p (type, TREE_TYPE (@0)))
734 || (GENERIC && type == TREE_TYPE (@0)))
735 @0)))
736
737 /* Contract view-conversions. */
738 (simplify
739 (view_convert (view_convert @0))
740 (view_convert @0))
741
742 /* For integral conversions with the same precision or pointer
743 conversions use a NOP_EXPR instead. */
744 (simplify
745 (view_convert @0)
746 (if ((INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type))
747 && (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
748 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (@0)))
749 (convert @0)))
750
751 /* Strip inner integral conversions that do not change precision or size. */
752 (simplify
753 (view_convert (convert@0 @1))
754 (if ((INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
755 && (INTEGRAL_TYPE_P (TREE_TYPE (@1)) || POINTER_TYPE_P (TREE_TYPE (@1)))
756 && (TYPE_PRECISION (TREE_TYPE (@0)) == TYPE_PRECISION (TREE_TYPE (@1)))
757 && (TYPE_SIZE (TREE_TYPE (@0)) == TYPE_SIZE (TREE_TYPE (@1))))
758 (view_convert @1)))
759
760 /* Re-association barriers around constants and other re-association
761 barriers can be removed. */
762 (simplify
763 (paren CONSTANT_CLASS_P@0)
764 @0)
765 (simplify
766 (paren (paren@1 @0))
767 @1)
768
769 /* Handle cases of two conversions in a row. */
770 (for ocvt (convert float fix_trunc)
771 (for icvt (convert float)
772 (simplify
773 (ocvt (icvt@1 @0))
774 (with
775 {
776 tree inside_type = TREE_TYPE (@0);
777 tree inter_type = TREE_TYPE (@1);
778 int inside_int = INTEGRAL_TYPE_P (inside_type);
779 int inside_ptr = POINTER_TYPE_P (inside_type);
780 int inside_float = FLOAT_TYPE_P (inside_type);
781 int inside_vec = VECTOR_TYPE_P (inside_type);
782 unsigned int inside_prec = TYPE_PRECISION (inside_type);
783 int inside_unsignedp = TYPE_UNSIGNED (inside_type);
784 int inter_int = INTEGRAL_TYPE_P (inter_type);
785 int inter_ptr = POINTER_TYPE_P (inter_type);
786 int inter_float = FLOAT_TYPE_P (inter_type);
787 int inter_vec = VECTOR_TYPE_P (inter_type);
788 unsigned int inter_prec = TYPE_PRECISION (inter_type);
789 int inter_unsignedp = TYPE_UNSIGNED (inter_type);
790 int final_int = INTEGRAL_TYPE_P (type);
791 int final_ptr = POINTER_TYPE_P (type);
792 int final_float = FLOAT_TYPE_P (type);
793 int final_vec = VECTOR_TYPE_P (type);
794 unsigned int final_prec = TYPE_PRECISION (type);
795 int final_unsignedp = TYPE_UNSIGNED (type);
796 }
797 /* In addition to the cases of two conversions in a row
798 handled below, if we are converting something to its own
799 type via an object of identical or wider precision, neither
800 conversion is needed. */
801 (if (((GIMPLE && useless_type_conversion_p (type, inside_type))
802 || (GENERIC
803 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (inside_type)))
804 && (((inter_int || inter_ptr) && final_int)
805 || (inter_float && final_float))
806 && inter_prec >= final_prec)
807 (ocvt @0))
808
809 /* Likewise, if the intermediate and initial types are either both
810 float or both integer, we don't need the middle conversion if the
811 former is wider than the latter and doesn't change the signedness
812 (for integers). Avoid this if the final type is a pointer since
813 then we sometimes need the middle conversion. Likewise if the
814 final type has a precision not equal to the size of its mode. */
815 (if (((inter_int && inside_int) || (inter_float && inside_float))
816 && (final_int || final_float)
817 && inter_prec >= inside_prec
818 && (inter_float || inter_unsignedp == inside_unsignedp)
819 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
820 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
821 (ocvt @0))
822
823 /* If we have a sign-extension of a zero-extended value, we can
824 replace that by a single zero-extension. Likewise if the
825 final conversion does not change precision we can drop the
826 intermediate conversion. */
827 (if (inside_int && inter_int && final_int
828 && ((inside_prec < inter_prec && inter_prec < final_prec
829 && inside_unsignedp && !inter_unsignedp)
830 || final_prec == inter_prec))
831 (ocvt @0))
832
833 /* Two conversions in a row are not needed unless:
834 - some conversion is floating-point (overstrict for now), or
835 - some conversion is a vector (overstrict for now), or
836 - the intermediate type is narrower than both initial and
837 final, or
838 - the intermediate type and innermost type differ in signedness,
839 and the outermost type is wider than the intermediate, or
840 - the initial type is a pointer type and the precisions of the
841 intermediate and final types differ, or
842 - the final type is a pointer type and the precisions of the
843 initial and intermediate types differ. */
844 (if (! inside_float && ! inter_float && ! final_float
845 && ! inside_vec && ! inter_vec && ! final_vec
846 && (inter_prec >= inside_prec || inter_prec >= final_prec)
847 && ! (inside_int && inter_int
848 && inter_unsignedp != inside_unsignedp
849 && inter_prec < final_prec)
850 && ((inter_unsignedp && inter_prec > inside_prec)
851 == (final_unsignedp && final_prec > inter_prec))
852 && ! (inside_ptr && inter_prec != final_prec)
853 && ! (final_ptr && inside_prec != inter_prec)
854 && ! (final_prec != GET_MODE_PRECISION (TYPE_MODE (type))
855 && TYPE_MODE (type) == TYPE_MODE (inter_type)))
856 (ocvt @0))
857
858 /* A truncation to an unsigned type (a zero-extension) should be
859 canonicalized as bitwise and of a mask. */
860 (if (final_int && inter_int && inside_int
861 && final_prec == inside_prec
862 && final_prec > inter_prec
863 && inter_unsignedp)
864 (convert (bit_and @0 { wide_int_to_tree
865 (inside_type,
866 wi::mask (inter_prec, false,
867 TYPE_PRECISION (inside_type))); })))
868
869 /* If we are converting an integer to a floating-point that can
870 represent it exactly and back to an integer, we can skip the
871 floating-point conversion. */
872 (if (GIMPLE /* PR66211 */
873 && inside_int && inter_float && final_int &&
874 (unsigned) significand_size (TYPE_MODE (inter_type))
875 >= inside_prec - !inside_unsignedp)
876 (convert @0))))))
877
878 /* If we have a narrowing conversion to an integral type that is fed by a
879 BIT_AND_EXPR, we might be able to remove the BIT_AND_EXPR if it merely
880 masks off bits outside the final type (and nothing else). */
881 (simplify
882 (convert (bit_and @0 INTEGER_CST@1))
883 (if (INTEGRAL_TYPE_P (type)
884 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
885 && TYPE_PRECISION (type) <= TYPE_PRECISION (TREE_TYPE (@0))
886 && operand_equal_p (@1, build_low_bits_mask (TREE_TYPE (@1),
887 TYPE_PRECISION (type)), 0))
888 (convert @0)))
889
890
891 /* (X /[ex] A) * A -> X. */
892 (simplify
893 (mult (convert? (exact_div @0 @1)) @1)
894 /* Look through a sign-changing conversion. */
895 (convert @0))
896
897 /* Canonicalization of binary operations. */
898
899 /* Convert X + -C into X - C. */
900 (simplify
901 (plus @0 REAL_CST@1)
902 (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
903 (with { tree tem = fold_unary (NEGATE_EXPR, type, @1); }
904 (if (!TREE_OVERFLOW (tem) || !flag_trapping_math)
905 (minus @0 { tem; })))))
906
907 /* Convert x+x into x*2.0. */
908 (simplify
909 (plus @0 @0)
910 (if (SCALAR_FLOAT_TYPE_P (type))
911 (mult @0 { build_real (type, dconst2); })))
912
913 (simplify
914 (minus integer_zerop @1)
915 (negate @1))
916
917 /* (ARG0 - ARG1) is the same as (-ARG1 + ARG0). So check whether
918 ARG0 is zero and X + ARG0 reduces to X, since that would mean
919 (-ARG1 + ARG0) reduces to -ARG1. */
920 (simplify
921 (minus real_zerop@0 @1)
922 (if (fold_real_zero_addition_p (type, @0, 0))
923 (negate @1)))
924
925 /* Transform x * -1 into -x. */
926 (simplify
927 (mult @0 integer_minus_onep)
928 (negate @0))
929
930 /* COMPLEX_EXPR and REALPART/IMAGPART_EXPR cancellations. */
931 (simplify
932 (complex (realpart @0) (imagpart @0))
933 @0)
934 (simplify
935 (realpart (complex @0 @1))
936 @0)
937 (simplify
938 (imagpart (complex @0 @1))
939 @1)
940
941
942 /* BSWAP simplifications, transforms checked by gcc.dg/builtin-bswap-8.c. */
943 (for bswap (BUILT_IN_BSWAP16 BUILT_IN_BSWAP32 BUILT_IN_BSWAP64)
944 (simplify
945 (bswap (bswap @0))
946 @0)
947 (simplify
948 (bswap (bit_not (bswap @0)))
949 (bit_not @0))
950 (for bitop (bit_xor bit_ior bit_and)
951 (simplify
952 (bswap (bitop:c (bswap @0) @1))
953 (bitop @0 (bswap @1)))))
954
955
956 /* Combine COND_EXPRs and VEC_COND_EXPRs. */
957
958 /* Simplify constant conditions.
959 Only optimize constant conditions when the selected branch
960 has the same type as the COND_EXPR. This avoids optimizing
961 away "c ? x : throw", where the throw has a void type.
962 Note that we cannot throw away the fold-const.c variant nor
963 this one as we depend on doing this transform before possibly
964 A ? B : B -> B triggers and the fold-const.c one can optimize
965 0 ? A : B to B even if A has side-effects. Something
966 genmatch cannot handle. */
967 (simplify
968 (cond INTEGER_CST@0 @1 @2)
969 (if (integer_zerop (@0)
970 && (!VOID_TYPE_P (TREE_TYPE (@2))
971 || VOID_TYPE_P (type)))
972 @2)
973 (if (!integer_zerop (@0)
974 && (!VOID_TYPE_P (TREE_TYPE (@1))
975 || VOID_TYPE_P (type)))
976 @1))
977 (simplify
978 (vec_cond VECTOR_CST@0 @1 @2)
979 (if (integer_all_onesp (@0))
980 @1)
981 (if (integer_zerop (@0))
982 @2))
983
984 (for cnd (cond vec_cond)
985 /* A ? B : (A ? X : C) -> A ? B : C. */
986 (simplify
987 (cnd @0 (cnd @0 @1 @2) @3)
988 (cnd @0 @1 @3))
989 (simplify
990 (cnd @0 @1 (cnd @0 @2 @3))
991 (cnd @0 @1 @3))
992
993 /* A ? B : B -> B. */
994 (simplify
995 (cnd @0 @1 @1)
996 @1)
997
998 /* !A ? B : C -> A ? C : B. */
999 (simplify
1000 (cnd (logical_inverted_value truth_valued_p@0) @1 @2)
1001 (cnd @0 @2 @1)))
1002
1003
1004 /* Simplifications of comparisons. */
1005
1006 /* We can simplify a logical negation of a comparison to the
1007 inverted comparison. As we cannot compute an expression
1008 operator using invert_tree_comparison we have to simulate
1009 that with expression code iteration. */
1010 (for cmp (tcc_comparison)
1011 icmp (inverted_tcc_comparison)
1012 ncmp (inverted_tcc_comparison_with_nans)
1013 /* Ideally we'd like to combine the following two patterns
1014 and handle some more cases by using
1015 (logical_inverted_value (cmp @0 @1))
1016 here but for that genmatch would need to "inline" that.
1017 For now implement what forward_propagate_comparison did. */
1018 (simplify
1019 (bit_not (cmp @0 @1))
1020 (if (VECTOR_TYPE_P (type)
1021 || (INTEGRAL_TYPE_P (type) && TYPE_PRECISION (type) == 1))
1022 /* Comparison inversion may be impossible for trapping math,
1023 invert_tree_comparison will tell us. But we can't use
1024 a computed operator in the replacement tree thus we have
1025 to play the trick below. */
1026 (with { enum tree_code ic = invert_tree_comparison
1027 (cmp, HONOR_NANS (@0)); }
1028 (if (ic == icmp)
1029 (icmp @0 @1))
1030 (if (ic == ncmp)
1031 (ncmp @0 @1)))))
1032 (simplify
1033 (bit_xor (cmp @0 @1) integer_truep)
1034 (with { enum tree_code ic = invert_tree_comparison
1035 (cmp, HONOR_NANS (@0)); }
1036 (if (ic == icmp)
1037 (icmp @0 @1))
1038 (if (ic == ncmp)
1039 (ncmp @0 @1)))))
1040
1041 /* Unordered tests if either argument is a NaN. */
1042 (simplify
1043 (bit_ior (unordered @0 @0) (unordered @1 @1))
1044 (if (types_match (@0, @1))
1045 (unordered @0 @1)))
1046 (simplify
1047 (bit_and (ordered @0 @0) (ordered @1 @1))
1048 (if (types_match (@0, @1))
1049 (ordered @0 @1)))
1050 (simplify
1051 (bit_ior:c (unordered @0 @0) (unordered:c@2 @0 @1))
1052 @2)
1053 (simplify
1054 (bit_and:c (ordered @0 @0) (ordered:c@2 @0 @1))
1055 @2)
1056
1057 /* -A CMP -B -> B CMP A. */
1058 (for cmp (tcc_comparison)
1059 scmp (swapped_tcc_comparison)
1060 (simplify
1061 (cmp (negate @0) (negate @1))
1062 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1063 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1064 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1065 (scmp @0 @1)))
1066 (simplify
1067 (cmp (negate @0) CONSTANT_CLASS_P@1)
1068 (if (FLOAT_TYPE_P (TREE_TYPE (@0))
1069 || (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0))
1070 && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (@0))))
1071 (with { tree tem = fold_unary (NEGATE_EXPR, TREE_TYPE (@0), @1); }
1072 (if (tem && !TREE_OVERFLOW (tem))
1073 (scmp @0 { tem; }))))))
1074
1075 /* Simplification of math builtins. */
1076
1077 (define_operator_list LOG BUILT_IN_LOGF BUILT_IN_LOG BUILT_IN_LOGL)
1078 (define_operator_list EXP BUILT_IN_EXPF BUILT_IN_EXP BUILT_IN_EXPL)
1079 (define_operator_list LOG2 BUILT_IN_LOG2F BUILT_IN_LOG2 BUILT_IN_LOG2L)
1080 (define_operator_list EXP2 BUILT_IN_EXP2F BUILT_IN_EXP2 BUILT_IN_EXP2L)
1081 (define_operator_list LOG10 BUILT_IN_LOG10F BUILT_IN_LOG10 BUILT_IN_LOG10L)
1082 (define_operator_list EXP10 BUILT_IN_EXP10F BUILT_IN_EXP10 BUILT_IN_EXP10L)
1083 (define_operator_list POW BUILT_IN_POWF BUILT_IN_POW BUILT_IN_POWL)
1084 (define_operator_list POW10 BUILT_IN_POW10F BUILT_IN_POW10 BUILT_IN_POW10L)
1085 (define_operator_list SQRT BUILT_IN_SQRTF BUILT_IN_SQRT BUILT_IN_SQRTL)
1086 (define_operator_list CBRT BUILT_IN_CBRTF BUILT_IN_CBRT BUILT_IN_CBRTL)
1087
1088
1089 /* fold_builtin_logarithm */
1090 (if (flag_unsafe_math_optimizations)
1091 /* Special case, optimize logN(expN(x)) = x. */
1092 (for logs (LOG LOG2 LOG10)
1093 exps (EXP EXP2 EXP10)
1094 (simplify
1095 (logs (exps @0))
1096 @0))
1097 /* Optimize logN(func()) for various exponential functions. We
1098 want to determine the value "x" and the power "exponent" in
1099 order to transform logN(x**exponent) into exponent*logN(x). */
1100 (for logs (LOG LOG LOG LOG
1101 LOG2 LOG2 LOG2 LOG2
1102 LOG10 LOG10 LOG10 LOG10)
1103 exps (EXP EXP2 EXP10 POW10)
1104 (simplify
1105 (logs (exps @0))
1106 (with {
1107 tree x;
1108 switch (exps)
1109 {
1110 CASE_FLT_FN (BUILT_IN_EXP):
1111 /* Prepare to do logN(exp(exponent) -> exponent*logN(e). */
1112 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1113 dconst_e ()));
1114 break;
1115 CASE_FLT_FN (BUILT_IN_EXP2):
1116 /* Prepare to do logN(exp2(exponent) -> exponent*logN(2). */
1117 x = build_real (type, dconst2);
1118 break;
1119 CASE_FLT_FN (BUILT_IN_EXP10):
1120 CASE_FLT_FN (BUILT_IN_POW10):
1121 /* Prepare to do logN(exp10(exponent) -> exponent*logN(10). */
1122 {
1123 REAL_VALUE_TYPE dconst10;
1124 real_from_integer (&dconst10, VOIDmode, 10, SIGNED);
1125 x = build_real (type, dconst10);
1126 }
1127 break;
1128 }
1129 }
1130 (mult (logs { x; }) @0))))
1131 (for logs (LOG LOG
1132 LOG2 LOG2
1133 LOG10 LOG10)
1134 exps (SQRT CBRT)
1135 (simplify
1136 (logs (exps @0))
1137 (with {
1138 tree x;
1139 switch (exps)
1140 {
1141 CASE_FLT_FN (BUILT_IN_SQRT):
1142 /* Prepare to do logN(sqrt(x) -> 0.5*logN(x). */
1143 x = build_real (type, dconsthalf);
1144 break;
1145 CASE_FLT_FN (BUILT_IN_CBRT):
1146 /* Prepare to do logN(cbrt(x) -> (1/3)*logN(x). */
1147 x = build_real (type, real_value_truncate (TYPE_MODE (type),
1148 dconst_third ()));
1149 break;
1150 }
1151 }
1152 (mult { x; } (logs @0)))))
1153 /* logN(pow(x,exponent) -> exponent*logN(x). */
1154 (for logs (LOG LOG2 LOG10)
1155 pows (POW)
1156 (simplify
1157 (logs (pows @0 @1))
1158 (mult @1 (logs @0)))))
1159
1160 /* Narrowing of arithmetic and logical operations.
1161
1162 These are conceptually similar to the transformations performed for
1163 the C/C++ front-ends by shorten_binary_op and shorten_compare. Long
1164 term we want to move all that code out of the front-ends into here. */
1165
1166 /* If we have a narrowing conversion of an arithmetic operation where
1167 both operands are widening conversions from the same type as the outer
1168 narrowing conversion. Then convert the innermost operands to a suitable
1169 unsigned type (to avoid introducing undefined behaviour), perform the
1170 operation and convert the result to the desired type. */
1171 (for op (plus minus)
1172 (simplify
1173 (convert (op@4 (convert@2 @0) (convert@3 @1)))
1174 (if (INTEGRAL_TYPE_P (type)
1175 /* We check for type compatibility between @0 and @1 below,
1176 so there's no need to check that @1/@3 are integral types. */
1177 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1178 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
1179 /* The precision of the type of each operand must match the
1180 precision of the mode of each operand, similarly for the
1181 result. */
1182 && (TYPE_PRECISION (TREE_TYPE (@0))
1183 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
1184 && (TYPE_PRECISION (TREE_TYPE (@1))
1185 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
1186 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
1187 /* The inner conversion must be a widening conversion. */
1188 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
1189 && types_match (@0, @1)
1190 && types_match (@0, type)
1191 && single_use (@4))
1192 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
1193 (convert (op @0 @1)))
1194 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
1195 (convert (op (convert:utype @0) (convert:utype @1)))))))
1196
1197 /* This is another case of narrowing, specifically when there's an outer
1198 BIT_AND_EXPR which masks off bits outside the type of the innermost
1199 operands. Like the previous case we have to convert the operands
1200 to unsigned types to avoid introducing undefined behaviour for the
1201 arithmetic operation. */
1202 (for op (minus plus)
1203 (simplify
1204 (bit_and (op@5 (convert@2 @0) (convert@3 @1)) INTEGER_CST@4)
1205 (if (INTEGRAL_TYPE_P (type)
1206 /* We check for type compatibility between @0 and @1 below,
1207 so there's no need to check that @1/@3 are integral types. */
1208 && INTEGRAL_TYPE_P (TREE_TYPE (@0))
1209 && INTEGRAL_TYPE_P (TREE_TYPE (@2))
1210 /* The precision of the type of each operand must match the
1211 precision of the mode of each operand, similarly for the
1212 result. */
1213 && (TYPE_PRECISION (TREE_TYPE (@0))
1214 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@0))))
1215 && (TYPE_PRECISION (TREE_TYPE (@1))
1216 == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (@1))))
1217 && TYPE_PRECISION (type) == GET_MODE_PRECISION (TYPE_MODE (type))
1218 /* The inner conversion must be a widening conversion. */
1219 && TYPE_PRECISION (TREE_TYPE (@2)) > TYPE_PRECISION (TREE_TYPE (@0))
1220 && types_match (@0, @1)
1221 && (tree_int_cst_min_precision (@4, TYPE_SIGN (TREE_TYPE (@0)))
1222 <= TYPE_PRECISION (TREE_TYPE (@0)))
1223 && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0))
1224 || tree_int_cst_sgn (@4) >= 0)
1225 && single_use (@5))
1226 (if (TYPE_OVERFLOW_WRAPS (TREE_TYPE (@0)))
1227 (with { tree ntype = TREE_TYPE (@0); }
1228 (convert (bit_and (op @0 @1) (convert:ntype @4)))))
1229 (with { tree utype = unsigned_type_for (TREE_TYPE (@0)); }
1230 (convert (bit_and (op (convert:utype @0) (convert:utype @1))
1231 (convert:utype @4)))))))
1232