1 /* Target-dependent costs for expmed.cc.
2 Copyright (C) 1987-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef EXPMED_H
21 #define EXPMED_H 1
22
23 #include "insn-codes.h"
24
25 enum alg_code {
26 alg_unknown,
27 alg_zero,
28 alg_m, alg_shift,
29 alg_add_t_m2,
30 alg_sub_t_m2,
31 alg_add_factor,
32 alg_sub_factor,
33 alg_add_t2_m,
34 alg_sub_t2_m,
35 alg_impossible
36 };
37
38 /* Indicates the type of fixup needed after a constant multiplication.
39 BASIC_VARIANT means no fixup is needed, NEGATE_VARIANT means that
40 the result should be negated, and ADD_VARIANT means that the
41 multiplicand should be added to the result. */
42 enum mult_variant {basic_variant, negate_variant, add_variant};
43
44 bool choose_mult_variant (machine_mode, HOST_WIDE_INT,
45 struct algorithm *, enum mult_variant *, int);
46
47 /* This structure holds the "cost" of a multiply sequence. The
48 "cost" field holds the total rtx_cost of every operator in the
49 synthetic multiplication sequence, hence cost(a op b) is defined
50 as rtx_cost(op) + cost(a) + cost(b), where cost(leaf) is zero.
51 The "latency" field holds the minimum possible latency of the
52 synthetic multiply, on a hypothetical infinitely parallel CPU.
53 This is the critical path, or the maximum height, of the expression
54 tree which is the sum of rtx_costs on the most expensive path from
55 any leaf to the root. Hence latency(a op b) is defined as zero for
56 leaves and rtx_cost(op) + max(latency(a), latency(b)) otherwise. */
57
58 struct mult_cost {
59 short cost; /* Total rtx_cost of the multiplication sequence. */
60 short latency; /* The latency of the multiplication sequence. */
61 };
62
63 /* This macro is used to compare a pointer to a mult_cost against an
64 single integer "rtx_cost" value. This is equivalent to the macro
65 CHEAPER_MULT_COST(X,Z) where Z = {Y,Y}. */
66 #define MULT_COST_LESS(X,Y) ((X)->cost < (Y) \
67 || ((X)->cost == (Y) && (X)->latency < (Y)))
68
69 /* This macro is used to compare two pointers to mult_costs against
70 each other. The macro returns true if X is cheaper than Y.
71 Currently, the cheaper of two mult_costs is the one with the
72 lower "cost". If "cost"s are tied, the lower latency is cheaper. */
73 #define CHEAPER_MULT_COST(X,Y) ((X)->cost < (Y)->cost \
74 || ((X)->cost == (Y)->cost \
75 && (X)->latency < (Y)->latency))
76
77 /* This structure records a sequence of operations.
78 `ops' is the number of operations recorded.
79 `cost' is their total cost.
80 The operations are stored in `op' and the corresponding
81 logarithms of the integer coefficients in `log'.
82
83 These are the operations:
84 alg_zero total := 0;
85 alg_m total := multiplicand;
86 alg_shift total := total * coeff
87 alg_add_t_m2 total := total + multiplicand * coeff;
88 alg_sub_t_m2 total := total - multiplicand * coeff;
89 alg_add_factor total := total * coeff + total;
90 alg_sub_factor total := total * coeff - total;
91 alg_add_t2_m total := total * coeff + multiplicand;
92 alg_sub_t2_m total := total * coeff - multiplicand;
93
94 The first operand must be either alg_zero or alg_m. */
95
96 struct algorithm
97 {
98 struct mult_cost cost;
99 short ops;
100 /* The size of the OP and LOG fields are not directly related to the
101 word size, but the worst-case algorithms will be if we have few
102 consecutive ones or zeros, i.e., a multiplicand like 10101010101...
103 In that case we will generate shift-by-2, add, shift-by-2, add,...,
104 in total wordsize operations. */
105 enum alg_code op[MAX_BITS_PER_WORD];
106 char log[MAX_BITS_PER_WORD];
107 };
108
109 /* The entry for our multiplication cache/hash table. */
110 struct alg_hash_entry {
111 /* The number we are multiplying by. */
112 unsigned HOST_WIDE_INT t;
113
114 /* The mode in which we are multiplying something by T. */
115 machine_mode mode;
116
117 /* The best multiplication algorithm for t. */
118 enum alg_code alg;
119
120 /* The cost of multiplication if ALG_CODE is not alg_impossible.
121 Otherwise, the cost within which multiplication by T is
122 impossible. */
123 struct mult_cost cost;
124
125 /* Optimized for speed? */
126 bool speed;
127 };
128
129 /* The number of cache/hash entries. */
130 #if HOST_BITS_PER_WIDE_INT == 64
131 #define NUM_ALG_HASH_ENTRIES 1031
132 #else
133 #define NUM_ALG_HASH_ENTRIES 307
134 #endif
135
136 #define NUM_MODE_IP_INT (NUM_MODE_INT + NUM_MODE_PARTIAL_INT)
137 #define NUM_MODE_IPV_INT (NUM_MODE_IP_INT + NUM_MODE_VECTOR_INT)
138
139 struct expmed_op_cheap {
140 bool cheap[2][NUM_MODE_IPV_INT];
141 };
142
143 struct expmed_op_costs {
144 int cost[2][NUM_MODE_IPV_INT];
145 };
146
147 /* Target-dependent globals. */
148 struct target_expmed {
149 /* Each entry of ALG_HASH caches alg_code for some integer. This is
150 actually a hash table. If we have a collision, that the older
151 entry is kicked out. */
152 struct alg_hash_entry x_alg_hash[NUM_ALG_HASH_ENTRIES];
153
154 /* True if x_alg_hash might already have been used. */
155 bool x_alg_hash_used_p;
156
157 /* Nonzero means divides or modulus operations are relatively cheap for
158 powers of two, so don't use branches; emit the operation instead.
159 Usually, this will mean that the MD file will emit non-branch
160 sequences. */
161 struct expmed_op_cheap x_sdiv_pow2_cheap;
162 struct expmed_op_cheap x_smod_pow2_cheap;
163
164 /* Cost of various pieces of RTL. Note that some of these are indexed by
165 shift count and some by mode. */
166 int x_zero_cost[2];
167 struct expmed_op_costs x_add_cost;
168 struct expmed_op_costs x_neg_cost;
169 struct expmed_op_costs x_shift_cost[MAX_BITS_PER_WORD];
170 struct expmed_op_costs x_shiftadd_cost[MAX_BITS_PER_WORD];
171 struct expmed_op_costs x_shiftsub0_cost[MAX_BITS_PER_WORD];
172 struct expmed_op_costs x_shiftsub1_cost[MAX_BITS_PER_WORD];
173 struct expmed_op_costs x_mul_cost;
174 struct expmed_op_costs x_sdiv_cost;
175 struct expmed_op_costs x_udiv_cost;
176 int x_mul_widen_cost[2][NUM_MODE_INT];
177 int x_mul_highpart_cost[2][NUM_MODE_INT];
178
179 /* Conversion costs are only defined between two scalar integer modes
180 of different sizes. The first machine mode is the destination mode,
181 and the second is the source mode. */
182 int x_convert_cost[2][NUM_MODE_IP_INT][NUM_MODE_IP_INT];
183 };
184
185 extern struct target_expmed default_target_expmed;
186 #if SWITCHABLE_TARGET
187 extern struct target_expmed *this_target_expmed;
188 #else
189 #define this_target_expmed (&default_target_expmed)
190 #endif
191
192 /* Return a pointer to the alg_hash_entry at IDX. */
193
194 inline struct alg_hash_entry *
195 alg_hash_entry_ptr (int idx)
196 {
197 return &this_target_expmed->x_alg_hash[idx];
198 }
199
200 /* Return true if the x_alg_hash field might have been used. */
201
202 inline bool
203 alg_hash_used_p (void)
204 {
205 return this_target_expmed->x_alg_hash_used_p;
206 }
207
208 /* Set whether the x_alg_hash field might have been used. */
209
210 inline void
211 set_alg_hash_used_p (bool usedp)
212 {
213 this_target_expmed->x_alg_hash_used_p = usedp;
214 }
215
216 /* Compute an index into the cost arrays by mode class. */
217
218 inline int
219 expmed_mode_index (machine_mode mode)
220 {
221 switch (GET_MODE_CLASS (mode))
222 {
223 case MODE_INT:
224 return mode - MIN_MODE_INT;
225 case MODE_PARTIAL_INT:
226 /* If there are no partial integer modes, help the compiler
227 to figure out this will never happen. See PR59934. */
228 if (MIN_MODE_PARTIAL_INT != VOIDmode)
229 return mode - MIN_MODE_PARTIAL_INT + NUM_MODE_INT;
230 break;
231 case MODE_VECTOR_INT:
232 /* If there are no vector integer modes, help the compiler
233 to figure out this will never happen. See PR59934. */
234 if (MIN_MODE_VECTOR_INT != VOIDmode)
235 return mode - MIN_MODE_VECTOR_INT + NUM_MODE_IP_INT;
236 break;
237 default:
238 break;
239 }
240 gcc_unreachable ();
241 }
242
243 /* Return a pointer to a boolean contained in EOC indicating whether
244 a particular operation performed in MODE is cheap when optimizing
245 for SPEED. */
246
247 inline bool *
248 expmed_op_cheap_ptr (struct expmed_op_cheap *eoc, bool speed,
249 machine_mode mode)
250 {
251 int idx = expmed_mode_index (mode);
252 return &eoc->cheap[speed][idx];
253 }
254
255 /* Return a pointer to a cost contained in COSTS when a particular
256 operation is performed in MODE when optimizing for SPEED. */
257
258 inline int *
259 expmed_op_cost_ptr (struct expmed_op_costs *costs, bool speed,
260 machine_mode mode)
261 {
262 int idx = expmed_mode_index (mode);
263 return &costs->cost[speed][idx];
264 }
265
266 /* Subroutine of {set_,}sdiv_pow2_cheap. Not to be used otherwise. */
267
268 inline bool *
269 sdiv_pow2_cheap_ptr (bool speed, machine_mode mode)
270 {
271 return expmed_op_cheap_ptr (&this_target_expmed->x_sdiv_pow2_cheap,
272 speed, mode);
273 }
274
275 /* Set whether a signed division by a power of 2 is cheap in MODE
276 when optimizing for SPEED. */
277
278 inline void
279 set_sdiv_pow2_cheap (bool speed, machine_mode mode, bool cheap_p)
280 {
281 *sdiv_pow2_cheap_ptr (speed, mode) = cheap_p;
282 }
283
284 /* Return whether a signed division by a power of 2 is cheap in MODE
285 when optimizing for SPEED. */
286
287 inline bool
288 sdiv_pow2_cheap (bool speed, machine_mode mode)
289 {
290 return *sdiv_pow2_cheap_ptr (speed, mode);
291 }
292
293 /* Subroutine of {set_,}smod_pow2_cheap. Not to be used otherwise. */
294
295 inline bool *
296 smod_pow2_cheap_ptr (bool speed, machine_mode mode)
297 {
298 return expmed_op_cheap_ptr (&this_target_expmed->x_smod_pow2_cheap,
299 speed, mode);
300 }
301
302 /* Set whether a signed modulo by a power of 2 is CHEAP in MODE when
303 optimizing for SPEED. */
304
305 inline void
306 set_smod_pow2_cheap (bool speed, machine_mode mode, bool cheap)
307 {
308 *smod_pow2_cheap_ptr (speed, mode) = cheap;
309 }
310
311 /* Return whether a signed modulo by a power of 2 is cheap in MODE
312 when optimizing for SPEED. */
313
314 inline bool
315 smod_pow2_cheap (bool speed, machine_mode mode)
316 {
317 return *smod_pow2_cheap_ptr (speed, mode);
318 }
319
320 /* Subroutine of {set_,}zero_cost. Not to be used otherwise. */
321
322 inline int *
323 zero_cost_ptr (bool speed)
324 {
325 return &this_target_expmed->x_zero_cost[speed];
326 }
327
328 /* Set the COST of loading zero when optimizing for SPEED. */
329
330 inline void
331 set_zero_cost (bool speed, int cost)
332 {
333 *zero_cost_ptr (speed) = cost;
334 }
335
336 /* Return the COST of loading zero when optimizing for SPEED. */
337
338 inline int
339 zero_cost (bool speed)
340 {
341 return *zero_cost_ptr (speed);
342 }
343
344 /* Subroutine of {set_,}add_cost. Not to be used otherwise. */
345
346 inline int *
347 add_cost_ptr (bool speed, machine_mode mode)
348 {
349 return expmed_op_cost_ptr (&this_target_expmed->x_add_cost, speed, mode);
350 }
351
352 /* Set the COST of computing an add in MODE when optimizing for SPEED. */
353
354 inline void
355 set_add_cost (bool speed, machine_mode mode, int cost)
356 {
357 *add_cost_ptr (speed, mode) = cost;
358 }
359
360 /* Return the cost of computing an add in MODE when optimizing for SPEED. */
361
362 inline int
363 add_cost (bool speed, machine_mode mode)
364 {
365 return *add_cost_ptr (speed, mode);
366 }
367
368 /* Subroutine of {set_,}neg_cost. Not to be used otherwise. */
369
370 inline int *
371 neg_cost_ptr (bool speed, machine_mode mode)
372 {
373 return expmed_op_cost_ptr (&this_target_expmed->x_neg_cost, speed, mode);
374 }
375
376 /* Set the COST of computing a negation in MODE when optimizing for SPEED. */
377
378 inline void
379 set_neg_cost (bool speed, machine_mode mode, int cost)
380 {
381 *neg_cost_ptr (speed, mode) = cost;
382 }
383
384 /* Return the cost of computing a negation in MODE when optimizing for
385 SPEED. */
386
387 inline int
388 neg_cost (bool speed, machine_mode mode)
389 {
390 return *neg_cost_ptr (speed, mode);
391 }
392
393 /* Subroutine of {set_,}shift_cost. Not to be used otherwise. */
394
395 inline int *
396 shift_cost_ptr (bool speed, machine_mode mode, int bits)
397 {
398 return expmed_op_cost_ptr (&this_target_expmed->x_shift_cost[bits],
399 speed, mode);
400 }
401
402 /* Set the COST of doing a shift in MODE by BITS when optimizing for SPEED. */
403
404 inline void
405 set_shift_cost (bool speed, machine_mode mode, int bits, int cost)
406 {
407 *shift_cost_ptr (speed, mode, bits) = cost;
408 }
409
410 /* Return the cost of doing a shift in MODE by BITS when optimizing for
411 SPEED. */
412
413 inline int
414 shift_cost (bool speed, machine_mode mode, int bits)
415 {
416 return *shift_cost_ptr (speed, mode, bits);
417 }
418
419 /* Subroutine of {set_,}shiftadd_cost. Not to be used otherwise. */
420
421 inline int *
422 shiftadd_cost_ptr (bool speed, machine_mode mode, int bits)
423 {
424 return expmed_op_cost_ptr (&this_target_expmed->x_shiftadd_cost[bits],
425 speed, mode);
426 }
427
428 /* Set the COST of doing a shift in MODE by BITS followed by an add when
429 optimizing for SPEED. */
430
431 inline void
432 set_shiftadd_cost (bool speed, machine_mode mode, int bits, int cost)
433 {
434 *shiftadd_cost_ptr (speed, mode, bits) = cost;
435 }
436
437 /* Return the cost of doing a shift in MODE by BITS followed by an add
438 when optimizing for SPEED. */
439
440 inline int
441 shiftadd_cost (bool speed, machine_mode mode, int bits)
442 {
443 return *shiftadd_cost_ptr (speed, mode, bits);
444 }
445
446 /* Subroutine of {set_,}shiftsub0_cost. Not to be used otherwise. */
447
448 inline int *
449 shiftsub0_cost_ptr (bool speed, machine_mode mode, int bits)
450 {
451 return expmed_op_cost_ptr (&this_target_expmed->x_shiftsub0_cost[bits],
452 speed, mode);
453 }
454
455 /* Set the COST of doing a shift in MODE by BITS and then subtracting a
456 value when optimizing for SPEED. */
457
458 inline void
459 set_shiftsub0_cost (bool speed, machine_mode mode, int bits, int cost)
460 {
461 *shiftsub0_cost_ptr (speed, mode, bits) = cost;
462 }
463
464 /* Return the cost of doing a shift in MODE by BITS and then subtracting
465 a value when optimizing for SPEED. */
466
467 inline int
468 shiftsub0_cost (bool speed, machine_mode mode, int bits)
469 {
470 return *shiftsub0_cost_ptr (speed, mode, bits);
471 }
472
473 /* Subroutine of {set_,}shiftsub1_cost. Not to be used otherwise. */
474
475 inline int *
476 shiftsub1_cost_ptr (bool speed, machine_mode mode, int bits)
477 {
478 return expmed_op_cost_ptr (&this_target_expmed->x_shiftsub1_cost[bits],
479 speed, mode);
480 }
481
482 /* Set the COST of subtracting a shift in MODE by BITS from a value when
483 optimizing for SPEED. */
484
485 inline void
486 set_shiftsub1_cost (bool speed, machine_mode mode, int bits, int cost)
487 {
488 *shiftsub1_cost_ptr (speed, mode, bits) = cost;
489 }
490
491 /* Return the cost of subtracting a shift in MODE by BITS from a value
492 when optimizing for SPEED. */
493
494 inline int
495 shiftsub1_cost (bool speed, machine_mode mode, int bits)
496 {
497 return *shiftsub1_cost_ptr (speed, mode, bits);
498 }
499
500 /* Subroutine of {set_,}mul_cost. Not to be used otherwise. */
501
502 inline int *
503 mul_cost_ptr (bool speed, machine_mode mode)
504 {
505 return expmed_op_cost_ptr (&this_target_expmed->x_mul_cost, speed, mode);
506 }
507
508 /* Set the COST of doing a multiplication in MODE when optimizing for
509 SPEED. */
510
511 inline void
512 set_mul_cost (bool speed, machine_mode mode, int cost)
513 {
514 *mul_cost_ptr (speed, mode) = cost;
515 }
516
517 /* Return the cost of doing a multiplication in MODE when optimizing
518 for SPEED. */
519
520 inline int
521 mul_cost (bool speed, machine_mode mode)
522 {
523 return *mul_cost_ptr (speed, mode);
524 }
525
526 /* Subroutine of {set_,}sdiv_cost. Not to be used otherwise. */
527
528 inline int *
529 sdiv_cost_ptr (bool speed, machine_mode mode)
530 {
531 return expmed_op_cost_ptr (&this_target_expmed->x_sdiv_cost, speed, mode);
532 }
533
534 /* Set the COST of doing a signed division in MODE when optimizing
535 for SPEED. */
536
537 inline void
538 set_sdiv_cost (bool speed, machine_mode mode, int cost)
539 {
540 *sdiv_cost_ptr (speed, mode) = cost;
541 }
542
543 /* Return the cost of doing a signed division in MODE when optimizing
544 for SPEED. */
545
546 inline int
547 sdiv_cost (bool speed, machine_mode mode)
548 {
549 return *sdiv_cost_ptr (speed, mode);
550 }
551
552 /* Subroutine of {set_,}udiv_cost. Not to be used otherwise. */
553
554 inline int *
555 udiv_cost_ptr (bool speed, machine_mode mode)
556 {
557 return expmed_op_cost_ptr (&this_target_expmed->x_udiv_cost, speed, mode);
558 }
559
560 /* Set the COST of doing an unsigned division in MODE when optimizing
561 for SPEED. */
562
563 inline void
564 set_udiv_cost (bool speed, machine_mode mode, int cost)
565 {
566 *udiv_cost_ptr (speed, mode) = cost;
567 }
568
569 /* Return the cost of doing an unsigned division in MODE when
570 optimizing for SPEED. */
571
572 inline int
573 udiv_cost (bool speed, machine_mode mode)
574 {
575 return *udiv_cost_ptr (speed, mode);
576 }
577
578 /* Subroutine of {set_,}mul_widen_cost. Not to be used otherwise. */
579
580 inline int *
581 mul_widen_cost_ptr (bool speed, machine_mode mode)
582 {
583 gcc_assert (GET_MODE_CLASS (mode) == MODE_INT);
584
585 return &this_target_expmed->x_mul_widen_cost[speed][mode - MIN_MODE_INT];
586 }
587
588 /* Set the COST for computing a widening multiplication in MODE when
589 optimizing for SPEED. */
590
591 inline void
592 set_mul_widen_cost (bool speed, machine_mode mode, int cost)
593 {
594 *mul_widen_cost_ptr (speed, mode) = cost;
595 }
596
597 /* Return the cost for computing a widening multiplication in MODE when
598 optimizing for SPEED. */
599
600 inline int
601 mul_widen_cost (bool speed, machine_mode mode)
602 {
603 return *mul_widen_cost_ptr (speed, mode);
604 }
605
606 /* Subroutine of {set_,}mul_highpart_cost. Not to be used otherwise. */
607
608 inline int *
609 mul_highpart_cost_ptr (bool speed, machine_mode mode)
610 {
611 gcc_assert (GET_MODE_CLASS (mode) == MODE_INT);
612 int m = mode - MIN_MODE_INT;
613 gcc_assert (m < NUM_MODE_INT);
614
615 return &this_target_expmed->x_mul_highpart_cost[speed][m];
616 }
617
618 /* Set the COST for computing the high part of a multiplication in MODE
619 when optimizing for SPEED. */
620
621 inline void
622 set_mul_highpart_cost (bool speed, machine_mode mode, int cost)
623 {
624 *mul_highpart_cost_ptr (speed, mode) = cost;
625 }
626
627 /* Return the cost for computing the high part of a multiplication in MODE
628 when optimizing for SPEED. */
629
630 inline int
631 mul_highpart_cost (bool speed, machine_mode mode)
632 {
633 return *mul_highpart_cost_ptr (speed, mode);
634 }
635
636 /* Subroutine of {set_,}convert_cost. Not to be used otherwise. */
637
638 inline int *
639 convert_cost_ptr (machine_mode to_mode, machine_mode from_mode,
640 bool speed)
641 {
642 int to_idx = expmed_mode_index (to_mode);
643 int from_idx = expmed_mode_index (from_mode);
644
645 gcc_assert (IN_RANGE (to_idx, 0, NUM_MODE_IP_INT - 1));
646 gcc_assert (IN_RANGE (from_idx, 0, NUM_MODE_IP_INT - 1));
647
648 return &this_target_expmed->x_convert_cost[speed][to_idx][from_idx];
649 }
650
651 /* Set the COST for converting from FROM_MODE to TO_MODE when optimizing
652 for SPEED. */
653
654 inline void
655 set_convert_cost (machine_mode to_mode, machine_mode from_mode,
656 bool speed, int cost)
657 {
658 *convert_cost_ptr (to_mode, from_mode, speed) = cost;
659 }
660
661 /* Return the cost for converting from FROM_MODE to TO_MODE when optimizing
662 for SPEED. */
663
664 inline int
665 convert_cost (machine_mode to_mode, machine_mode from_mode,
666 bool speed)
667 {
668 return *convert_cost_ptr (to_mode, from_mode, speed);
669 }
670
671 extern int mult_by_coeff_cost (HOST_WIDE_INT, machine_mode, bool);
672 extern rtx emit_cstore (rtx target, enum insn_code icode, enum rtx_code code,
673 machine_mode mode, machine_mode compare_mode,
674 int unsignedp, rtx x, rtx y, int normalizep,
675 machine_mode target_mode);
676
677 /* Arguments MODE, RTX: return an rtx for the negation of that value.
678 May emit insns. */
679 extern rtx negate_rtx (machine_mode, rtx);
680
681 /* Arguments MODE, RTX: return an rtx for the flipping of that value.
682 May emit insns. */
683 extern rtx flip_storage_order (machine_mode, rtx);
684
685 /* Expand a logical AND operation. */
686 extern rtx expand_and (machine_mode, rtx, rtx, rtx);
687
688 /* Emit a store-flag operation. */
689 extern rtx emit_store_flag (rtx, enum rtx_code, rtx, rtx, machine_mode,
690 int, int);
691
692 /* Like emit_store_flag, but always succeeds. */
693 extern rtx emit_store_flag_force (rtx, enum rtx_code, rtx, rtx,
694 machine_mode, int, int);
695
696 extern void canonicalize_comparison (machine_mode, enum rtx_code *, rtx *);
697
698 /* Choose a minimal N + 1 bit approximation to 1/D that can be used to
699 replace division by D, and put the least significant N bits of the result
700 in *MULTIPLIER_PTR and return the most significant bit. */
701 extern unsigned HOST_WIDE_INT choose_multiplier (unsigned HOST_WIDE_INT, int,
702 int, unsigned HOST_WIDE_INT *,
703 int *, int *);
704
705 #ifdef TREE_CODE
706 extern rtx expand_variable_shift (enum tree_code, machine_mode,
707 rtx, tree, rtx, int);
708 extern rtx expand_shift (enum tree_code, machine_mode, rtx, poly_int64, rtx,
709 int);
710 extern rtx maybe_expand_shift (enum tree_code, machine_mode, rtx, int, rtx,
711 int);
712 #ifdef GCC_OPTABS_H
713 extern rtx expand_divmod (int, enum tree_code, machine_mode, rtx, rtx,
714 rtx, int, enum optab_methods = OPTAB_LIB_WIDEN);
715 #endif
716 #endif
717
718 extern void store_bit_field (rtx, poly_uint64, poly_uint64,
719 poly_uint64, poly_uint64,
720 machine_mode, rtx, bool, bool);
721 extern rtx extract_bit_field (rtx, poly_uint64, poly_uint64, int, rtx,
722 machine_mode, machine_mode, bool, rtx *);
723 extern rtx extract_low_bits (machine_mode, machine_mode, rtx);
724 extern rtx expand_mult (machine_mode, rtx, rtx, rtx, int, bool = false);
725 extern rtx expand_mult_highpart_adjust (scalar_int_mode, rtx, rtx, rtx,
726 rtx, int);
727
728 #endif // EXPMED_H