1 | /* Optimize jump instructions, for GNU compiler. |
2 | Copyright (C) 1987-2024 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 | /* This is the pathetic reminder of old fame of the jump-optimization pass |
21 | of the compiler. Now it contains basically a set of utility functions to |
22 | operate with jumps. |
23 | |
24 | Each CODE_LABEL has a count of the times it is used |
25 | stored in the LABEL_NUSES internal field, and each JUMP_INSN |
26 | has one label that it refers to stored in the |
27 | JUMP_LABEL internal field. With this we can detect labels that |
28 | become unused because of the deletion of all the jumps that |
29 | formerly used them. The JUMP_LABEL info is sometimes looked |
30 | at by later passes. For return insns, it contains either a |
31 | RETURN or a SIMPLE_RETURN rtx. |
32 | |
33 | The subroutines redirect_jump and invert_jump are used |
34 | from other passes as well. */ |
35 | |
36 | #include "config.h" |
37 | #include "system.h" |
38 | #include "coretypes.h" |
39 | #include "backend.h" |
40 | #include "target.h" |
41 | #include "rtl.h" |
42 | #include "tree.h" |
43 | #include "cfghooks.h" |
44 | #include "tree-pass.h" |
45 | #include "memmodel.h" |
46 | #include "tm_p.h" |
47 | #include "insn-config.h" |
48 | #include "regs.h" |
49 | #include "emit-rtl.h" |
50 | #include "recog.h" |
51 | #include "cfgrtl.h" |
52 | #include "rtl-iter.h" |
53 | |
54 | /* Optimize jump y; x: ... y: jumpif... x? |
55 | Don't know if it is worth bothering with. */ |
56 | /* Optimize two cases of conditional jump to conditional jump? |
57 | This can never delete any instruction or make anything dead, |
58 | or even change what is live at any point. |
59 | So perhaps let combiner do it. */ |
60 | |
61 | static void init_label_info (rtx_insn *); |
62 | static void mark_all_labels (rtx_insn *); |
63 | static void mark_jump_label_1 (rtx, rtx_insn *, bool, bool); |
64 | static void mark_jump_label_asm (rtx, rtx_insn *); |
65 | static void redirect_exp_1 (rtx *, rtx, rtx, rtx_insn *); |
66 | static bool invert_exp_1 (rtx, rtx_insn *); |
67 | |
68 | /* Worker for rebuild_jump_labels and rebuild_jump_labels_chain. */ |
69 | static void |
70 | rebuild_jump_labels_1 (rtx_insn *f, bool count_forced) |
71 | { |
72 | timevar_push (tv: TV_REBUILD_JUMP); |
73 | init_label_info (f); |
74 | mark_all_labels (f); |
75 | |
76 | /* Keep track of labels used from static data; we don't track them |
77 | closely enough to delete them here, so make sure their reference |
78 | count doesn't drop to zero. */ |
79 | |
80 | if (count_forced) |
81 | { |
82 | rtx_insn *insn; |
83 | unsigned int i; |
84 | FOR_EACH_VEC_SAFE_ELT (forced_labels, i, insn) |
85 | if (LABEL_P (insn)) |
86 | LABEL_NUSES (insn)++; |
87 | } |
88 | timevar_pop (tv: TV_REBUILD_JUMP); |
89 | } |
90 | |
91 | /* This function rebuilds the JUMP_LABEL field and REG_LABEL_TARGET |
92 | notes in jumping insns and REG_LABEL_OPERAND notes in non-jumping |
93 | instructions and jumping insns that have labels as operands |
94 | (e.g. cbranchsi4). */ |
95 | void |
96 | rebuild_jump_labels (rtx_insn *f) |
97 | { |
98 | rebuild_jump_labels_1 (f, count_forced: true); |
99 | } |
100 | |
101 | /* This function is like rebuild_jump_labels, but doesn't run over |
102 | forced_labels. It can be used on insn chains that aren't the |
103 | main function chain. */ |
104 | void |
105 | rebuild_jump_labels_chain (rtx_insn *chain) |
106 | { |
107 | rebuild_jump_labels_1 (f: chain, count_forced: false); |
108 | } |
109 | |
110 | /* Some old code expects exactly one BARRIER as the NEXT_INSN of a |
111 | non-fallthru insn. This is not generally true, as multiple barriers |
112 | may have crept in, or the BARRIER may be separated from the last |
113 | real insn by one or more NOTEs. |
114 | |
115 | This simple pass moves barriers and removes duplicates so that the |
116 | old code is happy. |
117 | */ |
118 | static unsigned int |
119 | cleanup_barriers (void) |
120 | { |
121 | rtx_insn *insn; |
122 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
123 | { |
124 | if (BARRIER_P (insn)) |
125 | { |
126 | rtx_insn *prev = prev_nonnote_nondebug_insn (insn); |
127 | if (!prev) |
128 | continue; |
129 | |
130 | if (BARRIER_P (prev)) |
131 | delete_insn (insn); |
132 | else if (prev != PREV_INSN (insn)) |
133 | { |
134 | basic_block bb = BLOCK_FOR_INSN (insn: prev); |
135 | rtx_insn *end = PREV_INSN (insn); |
136 | reorder_insns_nobb (insn, insn, prev); |
137 | if (bb) |
138 | { |
139 | /* If the backend called in machine reorg compute_bb_for_insn |
140 | and didn't free_bb_for_insn again, preserve basic block |
141 | boundaries. Move the end of basic block to PREV since |
142 | it is followed by a barrier now, and clear BLOCK_FOR_INSN |
143 | on the following notes. |
144 | ??? Maybe the proper solution for the targets that have |
145 | cfg around after machine reorg is not to run cleanup_barriers |
146 | pass at all. */ |
147 | BB_END (bb) = prev; |
148 | do |
149 | { |
150 | prev = NEXT_INSN (insn: prev); |
151 | if (prev != insn && BLOCK_FOR_INSN (insn: prev) == bb) |
152 | BLOCK_FOR_INSN (insn: prev) = NULL; |
153 | } |
154 | while (prev != end); |
155 | } |
156 | } |
157 | } |
158 | } |
159 | return 0; |
160 | } |
161 | |
162 | namespace { |
163 | |
164 | const pass_data pass_data_cleanup_barriers = |
165 | { |
166 | .type: RTL_PASS, /* type */ |
167 | .name: "barriers" , /* name */ |
168 | .optinfo_flags: OPTGROUP_NONE, /* optinfo_flags */ |
169 | .tv_id: TV_NONE, /* tv_id */ |
170 | .properties_required: 0, /* properties_required */ |
171 | .properties_provided: 0, /* properties_provided */ |
172 | .properties_destroyed: 0, /* properties_destroyed */ |
173 | .todo_flags_start: 0, /* todo_flags_start */ |
174 | .todo_flags_finish: 0, /* todo_flags_finish */ |
175 | }; |
176 | |
177 | class pass_cleanup_barriers : public rtl_opt_pass |
178 | { |
179 | public: |
180 | pass_cleanup_barriers (gcc::context *ctxt) |
181 | : rtl_opt_pass (pass_data_cleanup_barriers, ctxt) |
182 | {} |
183 | |
184 | /* opt_pass methods: */ |
185 | unsigned int execute (function *) final override |
186 | { |
187 | return cleanup_barriers (); |
188 | } |
189 | |
190 | }; // class pass_cleanup_barriers |
191 | |
192 | } // anon namespace |
193 | |
194 | rtl_opt_pass * |
195 | make_pass_cleanup_barriers (gcc::context *ctxt) |
196 | { |
197 | return new pass_cleanup_barriers (ctxt); |
198 | } |
199 | |
200 | |
201 | /* Initialize LABEL_NUSES and JUMP_LABEL fields, add REG_LABEL_TARGET |
202 | for remaining targets for JUMP_P. Delete any REG_LABEL_OPERAND |
203 | notes whose labels don't occur in the insn any more. */ |
204 | |
205 | static void |
206 | init_label_info (rtx_insn *f) |
207 | { |
208 | rtx_insn *insn; |
209 | |
210 | for (insn = f; insn; insn = NEXT_INSN (insn)) |
211 | { |
212 | if (LABEL_P (insn)) |
213 | LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0); |
214 | |
215 | /* REG_LABEL_TARGET notes (including the JUMP_LABEL field) are |
216 | sticky and not reset here; that way we won't lose association |
217 | with a label when e.g. the source for a target register |
218 | disappears out of reach for targets that may use jump-target |
219 | registers. Jump transformations are supposed to transform |
220 | any REG_LABEL_TARGET notes. The target label reference in a |
221 | branch may disappear from the branch (and from the |
222 | instruction before it) for other reasons, like register |
223 | allocation. */ |
224 | |
225 | if (INSN_P (insn)) |
226 | { |
227 | rtx note, next; |
228 | |
229 | for (note = REG_NOTES (insn); note; note = next) |
230 | { |
231 | next = XEXP (note, 1); |
232 | if (REG_NOTE_KIND (note) == REG_LABEL_OPERAND |
233 | && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn))) |
234 | remove_note (insn, note); |
235 | } |
236 | } |
237 | } |
238 | } |
239 | |
240 | /* A subroutine of mark_all_labels. Trivially propagate a simple label |
241 | load into a jump_insn that uses it. */ |
242 | |
243 | static void |
244 | maybe_propagate_label_ref (rtx_insn *jump_insn, rtx_insn *prev_nonjump_insn) |
245 | { |
246 | rtx label_note, pc, pc_src; |
247 | |
248 | pc = pc_set (jump_insn); |
249 | pc_src = pc != NULL ? SET_SRC (pc) : NULL; |
250 | label_note = find_reg_note (prev_nonjump_insn, REG_LABEL_OPERAND, NULL); |
251 | |
252 | /* If the previous non-jump insn sets something to a label, |
253 | something that this jump insn uses, make that label the primary |
254 | target of this insn if we don't yet have any. That previous |
255 | insn must be a single_set and not refer to more than one label. |
256 | The jump insn must not refer to other labels as jump targets |
257 | and must be a plain (set (pc) ...), maybe in a parallel, and |
258 | may refer to the item being set only directly or as one of the |
259 | arms in an IF_THEN_ELSE. */ |
260 | |
261 | if (label_note != NULL && pc_src != NULL) |
262 | { |
263 | rtx label_set = single_set (insn: prev_nonjump_insn); |
264 | rtx label_dest = label_set != NULL ? SET_DEST (label_set) : NULL; |
265 | |
266 | if (label_set != NULL |
267 | /* The source must be the direct LABEL_REF, not a |
268 | PLUS, UNSPEC, IF_THEN_ELSE etc. */ |
269 | && GET_CODE (SET_SRC (label_set)) == LABEL_REF |
270 | && (rtx_equal_p (label_dest, pc_src) |
271 | || (GET_CODE (pc_src) == IF_THEN_ELSE |
272 | && (rtx_equal_p (label_dest, XEXP (pc_src, 1)) |
273 | || rtx_equal_p (label_dest, XEXP (pc_src, 2)))))) |
274 | { |
275 | /* The CODE_LABEL referred to in the note must be the |
276 | CODE_LABEL in the LABEL_REF of the "set". We can |
277 | conveniently use it for the marker function, which |
278 | requires a LABEL_REF wrapping. */ |
279 | gcc_assert (XEXP (label_note, 0) == label_ref_label (SET_SRC (label_set))); |
280 | |
281 | mark_jump_label_1 (label_set, jump_insn, false, true); |
282 | |
283 | gcc_assert (JUMP_LABEL (jump_insn) == XEXP (label_note, 0)); |
284 | } |
285 | } |
286 | } |
287 | |
288 | /* Mark the label each jump jumps to. |
289 | Combine consecutive labels, and count uses of labels. */ |
290 | |
291 | static void |
292 | mark_all_labels (rtx_insn *f) |
293 | { |
294 | rtx_insn *insn; |
295 | |
296 | if (current_ir_type () == IR_RTL_CFGLAYOUT) |
297 | { |
298 | basic_block bb; |
299 | FOR_EACH_BB_FN (bb, cfun) |
300 | { |
301 | /* In cfglayout mode, we don't bother with trivial next-insn |
302 | propagation of LABEL_REFs into JUMP_LABEL. This will be |
303 | handled by other optimizers using better algorithms. */ |
304 | FOR_BB_INSNS (bb, insn) |
305 | { |
306 | gcc_assert (! insn->deleted ()); |
307 | if (NONDEBUG_INSN_P (insn)) |
308 | mark_jump_label (PATTERN (insn), insn, 0); |
309 | } |
310 | |
311 | /* In cfglayout mode, there may be non-insns between the |
312 | basic blocks. If those non-insns represent tablejump data, |
313 | they contain label references that we must record. */ |
314 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) |
315 | if (JUMP_TABLE_DATA_P (insn)) |
316 | mark_jump_label (PATTERN (insn), insn, 0); |
317 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) |
318 | if (JUMP_TABLE_DATA_P (insn)) |
319 | mark_jump_label (PATTERN (insn), insn, 0); |
320 | } |
321 | } |
322 | else |
323 | { |
324 | rtx_insn *prev_nonjump_insn = NULL; |
325 | for (insn = f; insn; insn = NEXT_INSN (insn)) |
326 | { |
327 | if (insn->deleted ()) |
328 | ; |
329 | else if (LABEL_P (insn)) |
330 | prev_nonjump_insn = NULL; |
331 | else if (JUMP_TABLE_DATA_P (insn)) |
332 | mark_jump_label (PATTERN (insn), insn, 0); |
333 | else if (NONDEBUG_INSN_P (insn)) |
334 | { |
335 | mark_jump_label (PATTERN (insn), insn, 0); |
336 | if (JUMP_P (insn)) |
337 | { |
338 | if (JUMP_LABEL (insn) == NULL && prev_nonjump_insn != NULL) |
339 | maybe_propagate_label_ref (jump_insn: insn, prev_nonjump_insn); |
340 | } |
341 | else |
342 | prev_nonjump_insn = insn; |
343 | } |
344 | } |
345 | } |
346 | } |
347 | |
348 | /* Given a comparison (CODE ARG0 ARG1), inside an insn, INSN, return a code |
349 | of reversed comparison if it is possible to do so. Otherwise return UNKNOWN. |
350 | UNKNOWN may be returned in case we are having CC_MODE compare and we don't |
351 | know whether it's source is floating point or integer comparison. Machine |
352 | description should define REVERSIBLE_CC_MODE and REVERSE_CONDITION macros |
353 | to help this function avoid overhead in these cases. */ |
354 | enum rtx_code |
355 | reversed_comparison_code_parts (enum rtx_code code, const_rtx arg0, |
356 | const_rtx arg1, const rtx_insn *insn) |
357 | { |
358 | machine_mode mode; |
359 | |
360 | /* If this is not actually a comparison, we can't reverse it. */ |
361 | if (GET_RTX_CLASS (code) != RTX_COMPARE |
362 | && GET_RTX_CLASS (code) != RTX_COMM_COMPARE) |
363 | return UNKNOWN; |
364 | |
365 | mode = GET_MODE (arg0); |
366 | if (mode == VOIDmode) |
367 | mode = GET_MODE (arg1); |
368 | |
369 | /* First see if machine description supplies us way to reverse the |
370 | comparison. Give it priority over everything else to allow |
371 | machine description to do tricks. */ |
372 | if (GET_MODE_CLASS (mode) == MODE_CC |
373 | && REVERSIBLE_CC_MODE (mode)) |
374 | return REVERSE_CONDITION (code, mode); |
375 | |
376 | /* Try a few special cases based on the comparison code. */ |
377 | switch (code) |
378 | { |
379 | case GEU: |
380 | case GTU: |
381 | case LEU: |
382 | case LTU: |
383 | case NE: |
384 | case EQ: |
385 | /* It is always safe to reverse EQ and NE, even for the floating |
386 | point. Similarly the unsigned comparisons are never used for |
387 | floating point so we can reverse them in the default way. */ |
388 | return reverse_condition (code); |
389 | case ORDERED: |
390 | case UNORDERED: |
391 | case LTGT: |
392 | case UNEQ: |
393 | /* In case we already see unordered comparison, we can be sure to |
394 | be dealing with floating point so we don't need any more tests. */ |
395 | return reverse_condition_maybe_unordered (code); |
396 | case UNLT: |
397 | case UNLE: |
398 | case UNGT: |
399 | case UNGE: |
400 | /* We don't have safe way to reverse these yet. */ |
401 | return UNKNOWN; |
402 | default: |
403 | break; |
404 | } |
405 | |
406 | if (GET_MODE_CLASS (mode) == MODE_CC) |
407 | { |
408 | /* Try to search for the comparison to determine the real mode. |
409 | This code is expensive, but with sane machine description it |
410 | will be never used, since REVERSIBLE_CC_MODE will return true |
411 | in all cases. */ |
412 | if (! insn) |
413 | return UNKNOWN; |
414 | |
415 | /* These CONST_CAST's are okay because prev_nonnote_insn just |
416 | returns its argument and we assign it to a const_rtx |
417 | variable. */ |
418 | for (rtx_insn *prev = prev_nonnote_insn (const_cast<rtx_insn *> (insn)); |
419 | prev != 0 && !LABEL_P (prev); |
420 | prev = prev_nonnote_insn (prev)) |
421 | { |
422 | const_rtx set = set_of (arg0, prev); |
423 | if (set && GET_CODE (set) == SET |
424 | && rtx_equal_p (SET_DEST (set), arg0)) |
425 | { |
426 | rtx src = SET_SRC (set); |
427 | |
428 | if (GET_CODE (src) == COMPARE) |
429 | { |
430 | rtx comparison = src; |
431 | arg0 = XEXP (src, 0); |
432 | mode = GET_MODE (arg0); |
433 | if (mode == VOIDmode) |
434 | mode = GET_MODE (XEXP (comparison, 1)); |
435 | break; |
436 | } |
437 | /* We can get past reg-reg moves. This may be useful for model |
438 | of i387 comparisons that first move flag registers around. */ |
439 | if (REG_P (src)) |
440 | { |
441 | arg0 = src; |
442 | continue; |
443 | } |
444 | } |
445 | /* If register is clobbered in some ununderstandable way, |
446 | give up. */ |
447 | if (set) |
448 | return UNKNOWN; |
449 | } |
450 | } |
451 | |
452 | /* Test for an integer condition, or a floating-point comparison |
453 | in which NaNs can be ignored. */ |
454 | if (CONST_INT_P (arg0) |
455 | || (GET_MODE (arg0) != VOIDmode |
456 | && GET_MODE_CLASS (mode) != MODE_CC |
457 | && !HONOR_NANS (mode))) |
458 | return reverse_condition (code); |
459 | |
460 | return UNKNOWN; |
461 | } |
462 | |
463 | /* A wrapper around the previous function to take COMPARISON as rtx |
464 | expression. This simplifies many callers. */ |
465 | enum rtx_code |
466 | reversed_comparison_code (const_rtx comparison, const rtx_insn *insn) |
467 | { |
468 | if (!COMPARISON_P (comparison)) |
469 | return UNKNOWN; |
470 | return reversed_comparison_code_parts (GET_CODE (comparison), |
471 | XEXP (comparison, 0), |
472 | XEXP (comparison, 1), insn); |
473 | } |
474 | |
475 | /* Return comparison with reversed code of EXP. |
476 | Return NULL_RTX in case we fail to do the reversal. */ |
477 | rtx |
478 | reversed_comparison (const_rtx exp, machine_mode mode) |
479 | { |
480 | enum rtx_code reversed_code = reversed_comparison_code (comparison: exp, NULL); |
481 | if (reversed_code == UNKNOWN) |
482 | return NULL_RTX; |
483 | else |
484 | return simplify_gen_relational (code: reversed_code, mode, VOIDmode, |
485 | XEXP (exp, 0), XEXP (exp, 1)); |
486 | } |
487 | |
488 | |
489 | /* Given an rtx-code for a comparison, return the code for the negated |
490 | comparison. If no such code exists, return UNKNOWN. |
491 | |
492 | WATCH OUT! reverse_condition is not safe to use on a jump that might |
493 | be acting on the results of an IEEE floating point comparison, because |
494 | of the special treatment of non-signaling nans in comparisons. |
495 | Use reversed_comparison_code instead. */ |
496 | |
497 | enum rtx_code |
498 | reverse_condition (enum rtx_code code) |
499 | { |
500 | switch (code) |
501 | { |
502 | case EQ: |
503 | return NE; |
504 | case NE: |
505 | return EQ; |
506 | case GT: |
507 | return LE; |
508 | case GE: |
509 | return LT; |
510 | case LT: |
511 | return GE; |
512 | case LE: |
513 | return GT; |
514 | case GTU: |
515 | return LEU; |
516 | case GEU: |
517 | return LTU; |
518 | case LTU: |
519 | return GEU; |
520 | case LEU: |
521 | return GTU; |
522 | case UNORDERED: |
523 | return ORDERED; |
524 | case ORDERED: |
525 | return UNORDERED; |
526 | |
527 | case UNLT: |
528 | case UNLE: |
529 | case UNGT: |
530 | case UNGE: |
531 | case UNEQ: |
532 | case LTGT: |
533 | return UNKNOWN; |
534 | |
535 | default: |
536 | gcc_unreachable (); |
537 | } |
538 | } |
539 | |
540 | /* Similar, but we're allowed to generate unordered comparisons, which |
541 | makes it safe for IEEE floating-point. Of course, we have to recognize |
542 | that the target will support them too... */ |
543 | |
544 | enum rtx_code |
545 | reverse_condition_maybe_unordered (enum rtx_code code) |
546 | { |
547 | switch (code) |
548 | { |
549 | case EQ: |
550 | return NE; |
551 | case NE: |
552 | return EQ; |
553 | case GT: |
554 | return UNLE; |
555 | case GE: |
556 | return UNLT; |
557 | case LT: |
558 | return UNGE; |
559 | case LE: |
560 | return UNGT; |
561 | case LTGT: |
562 | return UNEQ; |
563 | case UNORDERED: |
564 | return ORDERED; |
565 | case ORDERED: |
566 | return UNORDERED; |
567 | case UNLT: |
568 | return GE; |
569 | case UNLE: |
570 | return GT; |
571 | case UNGT: |
572 | return LE; |
573 | case UNGE: |
574 | return LT; |
575 | case UNEQ: |
576 | return LTGT; |
577 | |
578 | default: |
579 | gcc_unreachable (); |
580 | } |
581 | } |
582 | |
583 | /* Similar, but return the code when two operands of a comparison are swapped. |
584 | This IS safe for IEEE floating-point. */ |
585 | |
586 | enum rtx_code |
587 | swap_condition (enum rtx_code code) |
588 | { |
589 | switch (code) |
590 | { |
591 | case EQ: |
592 | case NE: |
593 | case UNORDERED: |
594 | case ORDERED: |
595 | case UNEQ: |
596 | case LTGT: |
597 | return code; |
598 | |
599 | case GT: |
600 | return LT; |
601 | case GE: |
602 | return LE; |
603 | case LT: |
604 | return GT; |
605 | case LE: |
606 | return GE; |
607 | case GTU: |
608 | return LTU; |
609 | case GEU: |
610 | return LEU; |
611 | case LTU: |
612 | return GTU; |
613 | case LEU: |
614 | return GEU; |
615 | case UNLT: |
616 | return UNGT; |
617 | case UNLE: |
618 | return UNGE; |
619 | case UNGT: |
620 | return UNLT; |
621 | case UNGE: |
622 | return UNLE; |
623 | |
624 | default: |
625 | gcc_unreachable (); |
626 | } |
627 | } |
628 | |
629 | /* Given a comparison CODE, return the corresponding unsigned comparison. |
630 | If CODE is an equality comparison or already an unsigned comparison, |
631 | CODE is returned. */ |
632 | |
633 | enum rtx_code |
634 | unsigned_condition (enum rtx_code code) |
635 | { |
636 | switch (code) |
637 | { |
638 | case EQ: |
639 | case NE: |
640 | case GTU: |
641 | case GEU: |
642 | case LTU: |
643 | case LEU: |
644 | return code; |
645 | |
646 | case GT: |
647 | return GTU; |
648 | case GE: |
649 | return GEU; |
650 | case LT: |
651 | return LTU; |
652 | case LE: |
653 | return LEU; |
654 | |
655 | default: |
656 | gcc_unreachable (); |
657 | } |
658 | } |
659 | |
660 | /* Similarly, return the signed version of a comparison. */ |
661 | |
662 | enum rtx_code |
663 | signed_condition (enum rtx_code code) |
664 | { |
665 | switch (code) |
666 | { |
667 | case EQ: |
668 | case NE: |
669 | case GT: |
670 | case GE: |
671 | case LT: |
672 | case LE: |
673 | return code; |
674 | |
675 | case GTU: |
676 | return GT; |
677 | case GEU: |
678 | return GE; |
679 | case LTU: |
680 | return LT; |
681 | case LEU: |
682 | return LE; |
683 | |
684 | default: |
685 | gcc_unreachable (); |
686 | } |
687 | } |
688 | |
689 | /* Return true if CODE1 is more strict than CODE2, i.e., if the |
690 | truth of CODE1 implies the truth of CODE2. */ |
691 | |
692 | bool |
693 | comparison_dominates_p (enum rtx_code code1, enum rtx_code code2) |
694 | { |
695 | /* UNKNOWN comparison codes can happen as a result of trying to revert |
696 | comparison codes. |
697 | They can't match anything, so we have to reject them here. */ |
698 | if (code1 == UNKNOWN || code2 == UNKNOWN) |
699 | return false; |
700 | |
701 | if (code1 == code2) |
702 | return true; |
703 | |
704 | switch (code1) |
705 | { |
706 | case UNEQ: |
707 | if (code2 == UNLE || code2 == UNGE) |
708 | return true; |
709 | break; |
710 | |
711 | case EQ: |
712 | if (code2 == LE || code2 == LEU || code2 == GE || code2 == GEU |
713 | || code2 == ORDERED) |
714 | return true; |
715 | break; |
716 | |
717 | case UNLT: |
718 | if (code2 == UNLE || code2 == NE) |
719 | return true; |
720 | break; |
721 | |
722 | case LT: |
723 | if (code2 == LE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
724 | return true; |
725 | break; |
726 | |
727 | case UNGT: |
728 | if (code2 == UNGE || code2 == NE) |
729 | return true; |
730 | break; |
731 | |
732 | case GT: |
733 | if (code2 == GE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
734 | return true; |
735 | break; |
736 | |
737 | case GE: |
738 | case LE: |
739 | if (code2 == ORDERED) |
740 | return true; |
741 | break; |
742 | |
743 | case LTGT: |
744 | if (code2 == NE || code2 == ORDERED) |
745 | return true; |
746 | break; |
747 | |
748 | case LTU: |
749 | if (code2 == LEU || code2 == NE) |
750 | return true; |
751 | break; |
752 | |
753 | case GTU: |
754 | if (code2 == GEU || code2 == NE) |
755 | return true; |
756 | break; |
757 | |
758 | case UNORDERED: |
759 | if (code2 == NE || code2 == UNEQ || code2 == UNLE || code2 == UNLT |
760 | || code2 == UNGE || code2 == UNGT) |
761 | return true; |
762 | break; |
763 | |
764 | default: |
765 | break; |
766 | } |
767 | |
768 | return false; |
769 | } |
770 | |
771 | /* Return true if INSN is an unconditional jump and nothing else. */ |
772 | |
773 | bool |
774 | simplejump_p (const rtx_insn *insn) |
775 | { |
776 | return (JUMP_P (insn) |
777 | && GET_CODE (PATTERN (insn)) == SET |
778 | && GET_CODE (SET_DEST (PATTERN (insn))) == PC |
779 | && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF); |
780 | } |
781 | |
782 | /* Return true if INSN is a (possibly) conditional jump |
783 | and nothing more. |
784 | |
785 | Use of this function is deprecated, since we need to support combined |
786 | branch and compare insns. Use any_condjump_p instead whenever possible. */ |
787 | |
788 | bool |
789 | condjump_p (const rtx_insn *insn) |
790 | { |
791 | const_rtx x = PATTERN (insn); |
792 | |
793 | if (GET_CODE (x) != SET |
794 | || GET_CODE (SET_DEST (x)) != PC) |
795 | return false; |
796 | |
797 | x = SET_SRC (x); |
798 | if (GET_CODE (x) == LABEL_REF) |
799 | return true; |
800 | else |
801 | return (GET_CODE (x) == IF_THEN_ELSE |
802 | && ((GET_CODE (XEXP (x, 2)) == PC |
803 | && (GET_CODE (XEXP (x, 1)) == LABEL_REF |
804 | || ANY_RETURN_P (XEXP (x, 1)))) |
805 | || (GET_CODE (XEXP (x, 1)) == PC |
806 | && (GET_CODE (XEXP (x, 2)) == LABEL_REF |
807 | || ANY_RETURN_P (XEXP (x, 2)))))); |
808 | } |
809 | |
810 | /* Return true if INSN is a (possibly) conditional jump inside a |
811 | PARALLEL. |
812 | |
813 | Use this function is deprecated, since we need to support combined |
814 | branch and compare insns. Use any_condjump_p instead whenever possible. */ |
815 | |
816 | bool |
817 | condjump_in_parallel_p (const rtx_insn *insn) |
818 | { |
819 | const_rtx x = PATTERN (insn); |
820 | |
821 | if (GET_CODE (x) != PARALLEL) |
822 | return false; |
823 | else |
824 | x = XVECEXP (x, 0, 0); |
825 | |
826 | if (GET_CODE (x) != SET) |
827 | return false; |
828 | if (GET_CODE (SET_DEST (x)) != PC) |
829 | return false; |
830 | if (GET_CODE (SET_SRC (x)) == LABEL_REF) |
831 | return true; |
832 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) |
833 | return false; |
834 | if (XEXP (SET_SRC (x), 2) == pc_rtx |
835 | && (GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF |
836 | || ANY_RETURN_P (XEXP (SET_SRC (x), 1)))) |
837 | return true; |
838 | if (XEXP (SET_SRC (x), 1) == pc_rtx |
839 | && (GET_CODE (XEXP (SET_SRC (x), 2)) == LABEL_REF |
840 | || ANY_RETURN_P (XEXP (SET_SRC (x), 2)))) |
841 | return true; |
842 | return false; |
843 | } |
844 | |
845 | /* Return set of PC, otherwise NULL. */ |
846 | |
847 | rtx |
848 | pc_set (const rtx_insn *insn) |
849 | { |
850 | rtx pat; |
851 | if (!JUMP_P (insn)) |
852 | return NULL_RTX; |
853 | pat = PATTERN (insn); |
854 | |
855 | /* The set is allowed to appear either as the insn pattern or |
856 | the first set in a PARALLEL, UNSPEC or UNSPEC_VOLATILE. */ |
857 | switch (GET_CODE (pat)) |
858 | { |
859 | case PARALLEL: |
860 | case UNSPEC: |
861 | case UNSPEC_VOLATILE: |
862 | pat = XVECEXP (pat, 0, 0); |
863 | break; |
864 | default: |
865 | break; |
866 | } |
867 | if (GET_CODE (pat) == SET && GET_CODE (SET_DEST (pat)) == PC) |
868 | return pat; |
869 | |
870 | return NULL_RTX; |
871 | } |
872 | |
873 | /* Return true when insn is an unconditional direct jump, |
874 | possibly bundled inside a PARALLEL, UNSPEC or UNSPEC_VOLATILE. |
875 | The instruction may have various other effects so before removing the jump |
876 | you must verify onlyjump_p. */ |
877 | |
878 | bool |
879 | any_uncondjump_p (const rtx_insn *insn) |
880 | { |
881 | const_rtx x = pc_set (insn); |
882 | if (!x) |
883 | return false; |
884 | if (GET_CODE (SET_SRC (x)) != LABEL_REF) |
885 | return false; |
886 | if (find_reg_note (insn, REG_NON_LOCAL_GOTO, NULL_RTX)) |
887 | return false; |
888 | return true; |
889 | } |
890 | |
891 | /* Return true when insn is a conditional jump. This function works for |
892 | instructions containing PC sets in PARALLELs, UNSPECs or UNSPEC_VOLATILEs. |
893 | The instruction may have various other effects so before removing the jump |
894 | you must verify onlyjump_p. |
895 | |
896 | Note that unlike condjump_p it returns false for unconditional jumps. */ |
897 | |
898 | bool |
899 | any_condjump_p (const rtx_insn *insn) |
900 | { |
901 | const_rtx x = pc_set (insn); |
902 | enum rtx_code a, b; |
903 | |
904 | if (!x) |
905 | return false; |
906 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) |
907 | return false; |
908 | |
909 | a = GET_CODE (XEXP (SET_SRC (x), 1)); |
910 | b = GET_CODE (XEXP (SET_SRC (x), 2)); |
911 | |
912 | return ((b == PC && (a == LABEL_REF || a == RETURN || a == SIMPLE_RETURN)) |
913 | || (a == PC |
914 | && (b == LABEL_REF || b == RETURN || b == SIMPLE_RETURN))); |
915 | } |
916 | |
917 | /* Return the label of a conditional jump. */ |
918 | |
919 | rtx |
920 | condjump_label (const rtx_insn *insn) |
921 | { |
922 | rtx x = pc_set (insn); |
923 | |
924 | if (!x) |
925 | return NULL_RTX; |
926 | x = SET_SRC (x); |
927 | if (GET_CODE (x) == LABEL_REF) |
928 | return x; |
929 | if (GET_CODE (x) != IF_THEN_ELSE) |
930 | return NULL_RTX; |
931 | if (XEXP (x, 2) == pc_rtx && GET_CODE (XEXP (x, 1)) == LABEL_REF) |
932 | return XEXP (x, 1); |
933 | if (XEXP (x, 1) == pc_rtx && GET_CODE (XEXP (x, 2)) == LABEL_REF) |
934 | return XEXP (x, 2); |
935 | return NULL_RTX; |
936 | } |
937 | |
938 | /* Return TRUE if INSN is a return jump. */ |
939 | |
940 | bool |
941 | returnjump_p (const rtx_insn *insn) |
942 | { |
943 | if (JUMP_P (insn)) |
944 | { |
945 | subrtx_iterator::array_type array; |
946 | FOR_EACH_SUBRTX (iter, array, PATTERN (insn), NONCONST) |
947 | { |
948 | const_rtx x = *iter; |
949 | switch (GET_CODE (x)) |
950 | { |
951 | case RETURN: |
952 | case SIMPLE_RETURN: |
953 | case EH_RETURN: |
954 | return true; |
955 | |
956 | case SET: |
957 | if (SET_IS_RETURN_P (x)) |
958 | return true; |
959 | break; |
960 | |
961 | default: |
962 | break; |
963 | } |
964 | } |
965 | } |
966 | return false; |
967 | } |
968 | |
969 | /* Return true if INSN is a (possibly conditional) return insn. */ |
970 | |
971 | bool |
972 | eh_returnjump_p (rtx_insn *insn) |
973 | { |
974 | if (JUMP_P (insn)) |
975 | { |
976 | subrtx_iterator::array_type array; |
977 | FOR_EACH_SUBRTX (iter, array, PATTERN (insn), NONCONST) |
978 | if (GET_CODE (*iter) == EH_RETURN) |
979 | return true; |
980 | } |
981 | return false; |
982 | } |
983 | |
984 | /* Return true if INSN is a jump that only transfers control and |
985 | nothing more. */ |
986 | |
987 | bool |
988 | onlyjump_p (const rtx_insn *insn) |
989 | { |
990 | rtx set; |
991 | |
992 | if (!JUMP_P (insn)) |
993 | return false; |
994 | |
995 | set = single_set (insn); |
996 | if (set == NULL) |
997 | return false; |
998 | if (GET_CODE (SET_DEST (set)) != PC) |
999 | return false; |
1000 | if (side_effects_p (SET_SRC (set))) |
1001 | return false; |
1002 | |
1003 | return true; |
1004 | } |
1005 | |
1006 | /* Return true iff INSN is a jump and its JUMP_LABEL is a label, not |
1007 | NULL or a return. */ |
1008 | bool |
1009 | jump_to_label_p (const rtx_insn *insn) |
1010 | { |
1011 | return (JUMP_P (insn) |
1012 | && JUMP_LABEL (insn) != NULL && !ANY_RETURN_P (JUMP_LABEL (insn))); |
1013 | } |
1014 | |
1015 | /* Find all CODE_LABELs referred to in X, and increment their use |
1016 | counts. If INSN is a JUMP_INSN and there is at least one |
1017 | CODE_LABEL referenced in INSN as a jump target, then store the last |
1018 | one in JUMP_LABEL (INSN). For a tablejump, this must be the label |
1019 | for the ADDR_VEC. Store any other jump targets as REG_LABEL_TARGET |
1020 | notes. If INSN is an INSN or a CALL_INSN or non-target operands of |
1021 | a JUMP_INSN, and there is at least one CODE_LABEL referenced in |
1022 | INSN, add a REG_LABEL_OPERAND note containing that label to INSN. |
1023 | For returnjumps, the JUMP_LABEL will also be set as appropriate. |
1024 | |
1025 | Note that two labels separated by a loop-beginning note |
1026 | must be kept distinct if we have not yet done loop-optimization, |
1027 | because the gap between them is where loop-optimize |
1028 | will want to move invariant code to. CROSS_JUMP tells us |
1029 | that loop-optimization is done with. */ |
1030 | |
1031 | void |
1032 | mark_jump_label (rtx x, rtx_insn *insn, int in_mem) |
1033 | { |
1034 | rtx asmop = extract_asm_operands (x); |
1035 | if (asmop) |
1036 | mark_jump_label_asm (asmop, insn); |
1037 | else |
1038 | mark_jump_label_1 (x, insn, in_mem != 0, |
1039 | (insn != NULL && x == PATTERN (insn) && JUMP_P (insn))); |
1040 | } |
1041 | |
1042 | /* Worker function for mark_jump_label. IN_MEM is TRUE when X occurs |
1043 | within a (MEM ...). IS_TARGET is TRUE when X is to be treated as a |
1044 | jump-target; when the JUMP_LABEL field of INSN should be set or a |
1045 | REG_LABEL_TARGET note should be added, not a REG_LABEL_OPERAND |
1046 | note. */ |
1047 | |
1048 | static void |
1049 | mark_jump_label_1 (rtx x, rtx_insn *insn, bool in_mem, bool is_target) |
1050 | { |
1051 | RTX_CODE code = GET_CODE (x); |
1052 | int i; |
1053 | const char *fmt; |
1054 | |
1055 | switch (code) |
1056 | { |
1057 | case PC: |
1058 | case REG: |
1059 | case CLOBBER: |
1060 | case CALL: |
1061 | return; |
1062 | |
1063 | case RETURN: |
1064 | case SIMPLE_RETURN: |
1065 | if (is_target) |
1066 | { |
1067 | gcc_assert (JUMP_LABEL (insn) == NULL || JUMP_LABEL (insn) == x); |
1068 | JUMP_LABEL (insn) = x; |
1069 | } |
1070 | return; |
1071 | |
1072 | case MEM: |
1073 | in_mem = true; |
1074 | break; |
1075 | |
1076 | case SEQUENCE: |
1077 | { |
1078 | rtx_sequence *seq = as_a <rtx_sequence *> (p: x); |
1079 | for (i = 0; i < seq->len (); i++) |
1080 | mark_jump_label (x: PATTERN (insn: seq->insn (index: i)), |
1081 | insn: seq->insn (index: i), in_mem: 0); |
1082 | } |
1083 | return; |
1084 | |
1085 | case SYMBOL_REF: |
1086 | if (!in_mem) |
1087 | return; |
1088 | |
1089 | /* If this is a constant-pool reference, see if it is a label. */ |
1090 | if (CONSTANT_POOL_ADDRESS_P (x)) |
1091 | mark_jump_label_1 (x: get_pool_constant (x), insn, in_mem, is_target); |
1092 | break; |
1093 | |
1094 | /* Handle operands in the condition of an if-then-else as for a |
1095 | non-jump insn. */ |
1096 | case IF_THEN_ELSE: |
1097 | if (!is_target) |
1098 | break; |
1099 | mark_jump_label_1 (XEXP (x, 0), insn, in_mem, is_target: false); |
1100 | mark_jump_label_1 (XEXP (x, 1), insn, in_mem, is_target: true); |
1101 | mark_jump_label_1 (XEXP (x, 2), insn, in_mem, is_target: true); |
1102 | return; |
1103 | |
1104 | case LABEL_REF: |
1105 | { |
1106 | rtx_insn *label = label_ref_label (ref: x); |
1107 | |
1108 | /* Ignore remaining references to unreachable labels that |
1109 | have been deleted. */ |
1110 | if (NOTE_P (label) |
1111 | && NOTE_KIND (label) == NOTE_INSN_DELETED_LABEL) |
1112 | break; |
1113 | |
1114 | gcc_assert (LABEL_P (label)); |
1115 | |
1116 | /* Ignore references to labels of containing functions. */ |
1117 | if (LABEL_REF_NONLOCAL_P (x)) |
1118 | break; |
1119 | |
1120 | set_label_ref_label (ref: x, label); |
1121 | if (! insn || ! insn->deleted ()) |
1122 | ++LABEL_NUSES (label); |
1123 | |
1124 | if (insn) |
1125 | { |
1126 | if (is_target |
1127 | /* Do not change a previous setting of JUMP_LABEL. If the |
1128 | JUMP_LABEL slot is occupied by a different label, |
1129 | create a note for this label. */ |
1130 | && (JUMP_LABEL (insn) == NULL || JUMP_LABEL (insn) == label)) |
1131 | JUMP_LABEL (insn) = label; |
1132 | else |
1133 | { |
1134 | enum reg_note kind |
1135 | = is_target ? REG_LABEL_TARGET : REG_LABEL_OPERAND; |
1136 | |
1137 | /* Add a REG_LABEL_OPERAND or REG_LABEL_TARGET note |
1138 | for LABEL unless there already is one. All uses of |
1139 | a label, except for the primary target of a jump, |
1140 | must have such a note. */ |
1141 | if (! find_reg_note (insn, kind, label)) |
1142 | add_reg_note (insn, kind, label); |
1143 | } |
1144 | } |
1145 | return; |
1146 | } |
1147 | |
1148 | /* Do walk the labels in a vector, but not the first operand of an |
1149 | ADDR_DIFF_VEC. Don't set the JUMP_LABEL of a vector. */ |
1150 | case ADDR_VEC: |
1151 | case ADDR_DIFF_VEC: |
1152 | if (! insn->deleted ()) |
1153 | { |
1154 | int eltnum = code == ADDR_DIFF_VEC ? 1 : 0; |
1155 | |
1156 | for (i = 0; i < XVECLEN (x, eltnum); i++) |
1157 | mark_jump_label_1 (XVECEXP (x, eltnum, i), NULL, in_mem, |
1158 | is_target); |
1159 | } |
1160 | return; |
1161 | |
1162 | default: |
1163 | break; |
1164 | } |
1165 | |
1166 | fmt = GET_RTX_FORMAT (code); |
1167 | |
1168 | /* The primary target of a tablejump is the label of the ADDR_VEC, |
1169 | which is canonically mentioned *last* in the insn. To get it |
1170 | marked as JUMP_LABEL, we iterate over items in reverse order. */ |
1171 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
1172 | { |
1173 | if (fmt[i] == 'e') |
1174 | mark_jump_label_1 (XEXP (x, i), insn, in_mem, is_target); |
1175 | else if (fmt[i] == 'E') |
1176 | { |
1177 | int j; |
1178 | |
1179 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
1180 | mark_jump_label_1 (XVECEXP (x, i, j), insn, in_mem, |
1181 | is_target); |
1182 | } |
1183 | } |
1184 | } |
1185 | |
1186 | /* Worker function for mark_jump_label. Handle asm insns specially. |
1187 | In particular, output operands need not be considered so we can |
1188 | avoid re-scanning the replicated asm_operand. Also, the asm_labels |
1189 | need to be considered targets. */ |
1190 | |
1191 | static void |
1192 | mark_jump_label_asm (rtx asmop, rtx_insn *insn) |
1193 | { |
1194 | int i; |
1195 | |
1196 | for (i = ASM_OPERANDS_INPUT_LENGTH (asmop) - 1; i >= 0; --i) |
1197 | mark_jump_label_1 (ASM_OPERANDS_INPUT (asmop, i), insn, in_mem: false, is_target: false); |
1198 | |
1199 | for (i = ASM_OPERANDS_LABEL_LENGTH (asmop) - 1; i >= 0; --i) |
1200 | mark_jump_label_1 (ASM_OPERANDS_LABEL (asmop, i), insn, in_mem: false, is_target: true); |
1201 | } |
1202 | |
1203 | /* Delete insn INSN from the chain of insns and update label ref counts |
1204 | and delete insns now unreachable. |
1205 | |
1206 | Returns the first insn after INSN that was not deleted. |
1207 | |
1208 | Usage of this instruction is deprecated. Use delete_insn instead and |
1209 | subsequent cfg_cleanup pass to delete unreachable code if needed. */ |
1210 | |
1211 | rtx_insn * |
1212 | delete_related_insns (rtx uncast_insn) |
1213 | { |
1214 | rtx_insn *insn = as_a <rtx_insn *> (p: uncast_insn); |
1215 | bool was_code_label = LABEL_P (insn); |
1216 | rtx note; |
1217 | rtx_insn *next = NEXT_INSN (insn), *prev = PREV_INSN (insn); |
1218 | |
1219 | while (next && next->deleted ()) |
1220 | next = NEXT_INSN (insn: next); |
1221 | |
1222 | /* This insn is already deleted => return first following nondeleted. */ |
1223 | if (insn->deleted ()) |
1224 | return next; |
1225 | |
1226 | delete_insn (insn); |
1227 | |
1228 | /* If instruction is followed by a barrier, |
1229 | delete the barrier too. */ |
1230 | |
1231 | if (next != 0 && BARRIER_P (next)) |
1232 | delete_insn (next); |
1233 | |
1234 | /* If deleting a jump, decrement the count of the label, |
1235 | and delete the label if it is now unused. */ |
1236 | |
1237 | if (jump_to_label_p (insn)) |
1238 | { |
1239 | rtx lab = JUMP_LABEL (insn); |
1240 | rtx_jump_table_data *lab_next; |
1241 | |
1242 | if (LABEL_NUSES (lab) == 0) |
1243 | /* This can delete NEXT or PREV, |
1244 | either directly if NEXT is JUMP_LABEL (INSN), |
1245 | or indirectly through more levels of jumps. */ |
1246 | delete_related_insns (uncast_insn: lab); |
1247 | else if (tablejump_p (insn, NULL, &lab_next)) |
1248 | { |
1249 | /* If we're deleting the tablejump, delete the dispatch table. |
1250 | We may not be able to kill the label immediately preceding |
1251 | just yet, as it might be referenced in code leading up to |
1252 | the tablejump. */ |
1253 | delete_related_insns (uncast_insn: lab_next); |
1254 | } |
1255 | } |
1256 | |
1257 | /* Likewise if we're deleting a dispatch table. */ |
1258 | |
1259 | if (rtx_jump_table_data *table = dyn_cast <rtx_jump_table_data *> (p: insn)) |
1260 | { |
1261 | rtvec labels = table->get_labels (); |
1262 | int i; |
1263 | int len = GET_NUM_ELEM (labels); |
1264 | |
1265 | for (i = 0; i < len; i++) |
1266 | if (LABEL_NUSES (XEXP (RTVEC_ELT (labels, i), 0)) == 0) |
1267 | delete_related_insns (XEXP (RTVEC_ELT (labels, i), 0)); |
1268 | while (next && next->deleted ()) |
1269 | next = NEXT_INSN (insn: next); |
1270 | return next; |
1271 | } |
1272 | |
1273 | /* Likewise for any JUMP_P / INSN / CALL_INSN with a |
1274 | REG_LABEL_OPERAND or REG_LABEL_TARGET note. */ |
1275 | if (INSN_P (insn)) |
1276 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) |
1277 | if ((REG_NOTE_KIND (note) == REG_LABEL_OPERAND |
1278 | || REG_NOTE_KIND (note) == REG_LABEL_TARGET) |
1279 | /* This could also be a NOTE_INSN_DELETED_LABEL note. */ |
1280 | && LABEL_P (XEXP (note, 0))) |
1281 | if (LABEL_NUSES (XEXP (note, 0)) == 0) |
1282 | delete_related_insns (XEXP (note, 0)); |
1283 | |
1284 | while (prev && (prev->deleted () || NOTE_P (prev))) |
1285 | prev = PREV_INSN (insn: prev); |
1286 | |
1287 | /* If INSN was a label and a dispatch table follows it, |
1288 | delete the dispatch table. The tablejump must have gone already. |
1289 | It isn't useful to fall through into a table. */ |
1290 | |
1291 | if (was_code_label |
1292 | && NEXT_INSN (insn) != 0 |
1293 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) |
1294 | next = delete_related_insns (uncast_insn: NEXT_INSN (insn)); |
1295 | |
1296 | /* If INSN was a label, delete insns following it if now unreachable. */ |
1297 | |
1298 | if (was_code_label && prev && BARRIER_P (prev)) |
1299 | { |
1300 | enum rtx_code code; |
1301 | while (next) |
1302 | { |
1303 | code = GET_CODE (next); |
1304 | if (code == NOTE) |
1305 | next = NEXT_INSN (insn: next); |
1306 | /* Keep going past other deleted labels to delete what follows. */ |
1307 | else if (code == CODE_LABEL && next->deleted ()) |
1308 | next = NEXT_INSN (insn: next); |
1309 | /* Keep the (use (insn))s created by dbr_schedule, which needs |
1310 | them in order to track liveness relative to a previous |
1311 | barrier. */ |
1312 | else if (INSN_P (next) |
1313 | && GET_CODE (PATTERN (next)) == USE |
1314 | && INSN_P (XEXP (PATTERN (next), 0))) |
1315 | next = NEXT_INSN (insn: next); |
1316 | else if (code == BARRIER || INSN_P (next)) |
1317 | /* Note: if this deletes a jump, it can cause more |
1318 | deletion of unreachable code, after a different label. |
1319 | As long as the value from this recursive call is correct, |
1320 | this invocation functions correctly. */ |
1321 | next = delete_related_insns (uncast_insn: next); |
1322 | else |
1323 | break; |
1324 | } |
1325 | } |
1326 | |
1327 | /* I feel a little doubtful about this loop, |
1328 | but I see no clean and sure alternative way |
1329 | to find the first insn after INSN that is not now deleted. |
1330 | I hope this works. */ |
1331 | while (next && next->deleted ()) |
1332 | next = NEXT_INSN (insn: next); |
1333 | return next; |
1334 | } |
1335 | |
1336 | /* Delete a range of insns from FROM to TO, inclusive. |
1337 | This is for the sake of peephole optimization, so assume |
1338 | that whatever these insns do will still be done by a new |
1339 | peephole insn that will replace them. */ |
1340 | |
1341 | void |
1342 | delete_for_peephole (rtx_insn *from, rtx_insn *to) |
1343 | { |
1344 | rtx_insn *insn = from; |
1345 | |
1346 | while (1) |
1347 | { |
1348 | rtx_insn *next = NEXT_INSN (insn); |
1349 | rtx_insn *prev = PREV_INSN (insn); |
1350 | |
1351 | if (!NOTE_P (insn)) |
1352 | { |
1353 | insn->set_deleted(); |
1354 | |
1355 | /* Patch this insn out of the chain. */ |
1356 | /* We don't do this all at once, because we |
1357 | must preserve all NOTEs. */ |
1358 | if (prev) |
1359 | SET_NEXT_INSN (prev) = next; |
1360 | |
1361 | if (next) |
1362 | SET_PREV_INSN (next) = prev; |
1363 | } |
1364 | |
1365 | if (insn == to) |
1366 | break; |
1367 | insn = next; |
1368 | } |
1369 | |
1370 | /* Note that if TO is an unconditional jump |
1371 | we *do not* delete the BARRIER that follows, |
1372 | since the peephole that replaces this sequence |
1373 | is also an unconditional jump in that case. */ |
1374 | } |
1375 | |
1376 | /* A helper function for redirect_exp_1; examines its input X and returns |
1377 | either a LABEL_REF around a label, or a RETURN if X was NULL. */ |
1378 | static rtx |
1379 | redirect_target (rtx x) |
1380 | { |
1381 | if (x == NULL_RTX) |
1382 | return ret_rtx; |
1383 | if (!ANY_RETURN_P (x)) |
1384 | return gen_rtx_LABEL_REF (Pmode, x); |
1385 | return x; |
1386 | } |
1387 | |
1388 | /* Throughout LOC, redirect OLABEL to NLABEL. Treat null OLABEL or |
1389 | NLABEL as a return. Accrue modifications into the change group. */ |
1390 | |
1391 | static void |
1392 | redirect_exp_1 (rtx *loc, rtx olabel, rtx nlabel, rtx_insn *insn) |
1393 | { |
1394 | rtx x = *loc; |
1395 | RTX_CODE code = GET_CODE (x); |
1396 | int i; |
1397 | const char *fmt; |
1398 | |
1399 | if ((code == LABEL_REF && label_ref_label (ref: x) == olabel) |
1400 | || x == olabel) |
1401 | { |
1402 | x = redirect_target (x: nlabel); |
1403 | if (GET_CODE (x) == LABEL_REF && loc == &PATTERN (insn)) |
1404 | x = gen_rtx_SET (pc_rtx, x); |
1405 | validate_change (insn, loc, x, 1); |
1406 | return; |
1407 | } |
1408 | |
1409 | if (code == SET && SET_DEST (x) == pc_rtx |
1410 | && ANY_RETURN_P (nlabel) |
1411 | && GET_CODE (SET_SRC (x)) == LABEL_REF |
1412 | && label_ref_label (SET_SRC (x)) == olabel) |
1413 | { |
1414 | validate_change (insn, loc, nlabel, 1); |
1415 | return; |
1416 | } |
1417 | |
1418 | if (code == IF_THEN_ELSE) |
1419 | { |
1420 | /* Skip the condition of an IF_THEN_ELSE. We only want to |
1421 | change jump destinations, not eventual label comparisons. */ |
1422 | redirect_exp_1 (loc: &XEXP (x, 1), olabel, nlabel, insn); |
1423 | redirect_exp_1 (loc: &XEXP (x, 2), olabel, nlabel, insn); |
1424 | return; |
1425 | } |
1426 | |
1427 | fmt = GET_RTX_FORMAT (code); |
1428 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
1429 | { |
1430 | if (fmt[i] == 'e') |
1431 | redirect_exp_1 (loc: &XEXP (x, i), olabel, nlabel, insn); |
1432 | else if (fmt[i] == 'E') |
1433 | { |
1434 | int j; |
1435 | for (j = 0; j < XVECLEN (x, i); j++) |
1436 | redirect_exp_1 (loc: &XVECEXP (x, i, j), olabel, nlabel, insn); |
1437 | } |
1438 | } |
1439 | } |
1440 | |
1441 | /* Make JUMP go to NLABEL instead of where it jumps now. Accrue |
1442 | the modifications into the change group. Return false if we did |
1443 | not see how to do that. */ |
1444 | |
1445 | bool |
1446 | redirect_jump_1 (rtx_insn *jump, rtx nlabel) |
1447 | { |
1448 | int ochanges = num_validated_changes (); |
1449 | rtx *loc, asmop; |
1450 | |
1451 | gcc_assert (nlabel != NULL_RTX); |
1452 | asmop = extract_asm_operands (PATTERN (insn: jump)); |
1453 | if (asmop) |
1454 | { |
1455 | if (nlabel == NULL) |
1456 | return false; |
1457 | gcc_assert (ASM_OPERANDS_LABEL_LENGTH (asmop) == 1); |
1458 | loc = &ASM_OPERANDS_LABEL (asmop, 0); |
1459 | } |
1460 | else if (GET_CODE (PATTERN (jump)) == PARALLEL) |
1461 | loc = &XVECEXP (PATTERN (jump), 0, 0); |
1462 | else |
1463 | loc = &PATTERN (insn: jump); |
1464 | |
1465 | redirect_exp_1 (loc, JUMP_LABEL (jump), nlabel, insn: jump); |
1466 | return num_validated_changes () > ochanges; |
1467 | } |
1468 | |
1469 | /* Make JUMP go to NLABEL instead of where it jumps now. If the old |
1470 | jump target label is unused as a result, it and the code following |
1471 | it may be deleted. |
1472 | |
1473 | Normally, NLABEL will be a label, but it may also be a RETURN rtx; |
1474 | in that case we are to turn the jump into a (possibly conditional) |
1475 | return insn. |
1476 | |
1477 | The return value will be true if the change was made, false if it wasn't |
1478 | (this can only occur when trying to produce return insns). */ |
1479 | |
1480 | bool |
1481 | redirect_jump (rtx_jump_insn *jump, rtx nlabel, int delete_unused) |
1482 | { |
1483 | rtx olabel = jump->jump_label (); |
1484 | |
1485 | if (!nlabel) |
1486 | { |
1487 | /* If there is no label, we are asked to redirect to the EXIT block. |
1488 | When before the epilogue is emitted, return/simple_return cannot be |
1489 | created so we return false immediately. After the epilogue |
1490 | is emitted, we always expect a label, either a non-null label, or a |
1491 | return/simple_return RTX. */ |
1492 | |
1493 | if (!epilogue_completed) |
1494 | return false; |
1495 | gcc_unreachable (); |
1496 | } |
1497 | |
1498 | if (nlabel == olabel) |
1499 | return true; |
1500 | |
1501 | if (! redirect_jump_1 (jump, nlabel) || ! apply_change_group ()) |
1502 | return false; |
1503 | |
1504 | redirect_jump_2 (jump, olabel, nlabel, delete_unused, 0); |
1505 | return true; |
1506 | } |
1507 | |
1508 | /* Fix up JUMP_LABEL and label ref counts after OLABEL has been replaced with |
1509 | NLABEL in JUMP. |
1510 | If DELETE_UNUSED is positive, delete related insn to OLABEL if its ref |
1511 | count has dropped to zero. */ |
1512 | void |
1513 | redirect_jump_2 (rtx_jump_insn *jump, rtx olabel, rtx nlabel, int delete_unused, |
1514 | int invert) |
1515 | { |
1516 | rtx note; |
1517 | |
1518 | gcc_assert (JUMP_LABEL (jump) == olabel); |
1519 | |
1520 | /* Negative DELETE_UNUSED used to be used to signalize behavior on |
1521 | moving FUNCTION_END note. Just sanity check that no user still worry |
1522 | about this. */ |
1523 | gcc_assert (delete_unused >= 0); |
1524 | JUMP_LABEL (jump) = nlabel; |
1525 | if (!ANY_RETURN_P (nlabel)) |
1526 | ++LABEL_NUSES (nlabel); |
1527 | |
1528 | /* Update labels in any REG_EQUAL note. */ |
1529 | if ((note = find_reg_note (jump, REG_EQUAL, NULL_RTX)) != NULL_RTX) |
1530 | { |
1531 | if (ANY_RETURN_P (nlabel) |
1532 | || (invert && !invert_exp_1 (XEXP (note, 0), jump))) |
1533 | remove_note (jump, note); |
1534 | else |
1535 | { |
1536 | redirect_exp_1 (loc: &XEXP (note, 0), olabel, nlabel, insn: jump); |
1537 | confirm_change_group (); |
1538 | } |
1539 | } |
1540 | |
1541 | /* Handle the case where we had a conditional crossing jump to a return |
1542 | label and are now changing it into a direct conditional return. |
1543 | The jump is no longer crossing in that case. */ |
1544 | if (ANY_RETURN_P (nlabel)) |
1545 | CROSSING_JUMP_P (jump) = 0; |
1546 | |
1547 | if (!ANY_RETURN_P (olabel) |
1548 | && --LABEL_NUSES (olabel) == 0 && delete_unused > 0 |
1549 | /* Undefined labels will remain outside the insn stream. */ |
1550 | && INSN_UID (insn: olabel)) |
1551 | delete_related_insns (uncast_insn: olabel); |
1552 | if (invert) |
1553 | invert_br_probabilities (jump); |
1554 | } |
1555 | |
1556 | /* Invert the jump condition X contained in jump insn INSN. Accrue the |
1557 | modifications into the change group. Return true for success. */ |
1558 | static bool |
1559 | invert_exp_1 (rtx x, rtx_insn *insn) |
1560 | { |
1561 | RTX_CODE code = GET_CODE (x); |
1562 | |
1563 | if (code == IF_THEN_ELSE) |
1564 | { |
1565 | rtx comp = XEXP (x, 0); |
1566 | rtx tem; |
1567 | enum rtx_code reversed_code; |
1568 | |
1569 | /* We can do this in two ways: The preferable way, which can only |
1570 | be done if this is not an integer comparison, is to reverse |
1571 | the comparison code. Otherwise, swap the THEN-part and ELSE-part |
1572 | of the IF_THEN_ELSE. If we can't do either, fail. */ |
1573 | |
1574 | reversed_code = reversed_comparison_code (comparison: comp, insn); |
1575 | |
1576 | if (reversed_code != UNKNOWN) |
1577 | { |
1578 | validate_change (insn, &XEXP (x, 0), |
1579 | gen_rtx_fmt_ee (reversed_code, |
1580 | GET_MODE (comp), XEXP (comp, 0), |
1581 | XEXP (comp, 1)), |
1582 | 1); |
1583 | return true; |
1584 | } |
1585 | |
1586 | tem = XEXP (x, 1); |
1587 | validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1); |
1588 | validate_change (insn, &XEXP (x, 2), tem, 1); |
1589 | return true; |
1590 | } |
1591 | else |
1592 | return false; |
1593 | } |
1594 | |
1595 | /* Invert the condition of the jump JUMP, and make it jump to label |
1596 | NLABEL instead of where it jumps now. Accrue changes into the |
1597 | change group. Return false if we didn't see how to perform the |
1598 | inversion and redirection. */ |
1599 | |
1600 | bool |
1601 | invert_jump_1 (rtx_jump_insn *jump, rtx nlabel) |
1602 | { |
1603 | rtx x = pc_set (insn: jump); |
1604 | int ochanges; |
1605 | bool ok; |
1606 | |
1607 | ochanges = num_validated_changes (); |
1608 | if (x == NULL) |
1609 | return false; |
1610 | ok = invert_exp_1 (SET_SRC (x), insn: jump); |
1611 | gcc_assert (ok); |
1612 | |
1613 | if (num_validated_changes () == ochanges) |
1614 | return false; |
1615 | |
1616 | /* redirect_jump_1 will fail of nlabel == olabel, and the current use is |
1617 | in Pmode, so checking this is not merely an optimization. */ |
1618 | return nlabel == JUMP_LABEL (jump) || redirect_jump_1 (jump, nlabel); |
1619 | } |
1620 | |
1621 | /* Invert the condition of the jump JUMP, and make it jump to label |
1622 | NLABEL instead of where it jumps now. Return true if successful. */ |
1623 | |
1624 | bool |
1625 | invert_jump (rtx_jump_insn *jump, rtx nlabel, int delete_unused) |
1626 | { |
1627 | rtx olabel = JUMP_LABEL (jump); |
1628 | |
1629 | if (invert_jump_1 (jump, nlabel) && apply_change_group ()) |
1630 | { |
1631 | redirect_jump_2 (jump, olabel, nlabel, delete_unused, invert: 1); |
1632 | return true; |
1633 | } |
1634 | cancel_changes (0); |
1635 | return false; |
1636 | } |
1637 | |
1638 | |
1639 | /* Like rtx_equal_p except that it considers two REGs as equal |
1640 | if they renumber to the same value and considers two commutative |
1641 | operations to be the same if the order of the operands has been |
1642 | reversed. */ |
1643 | |
1644 | bool |
1645 | rtx_renumbered_equal_p (const_rtx x, const_rtx y) |
1646 | { |
1647 | int i; |
1648 | const enum rtx_code code = GET_CODE (x); |
1649 | const char *fmt; |
1650 | |
1651 | if (x == y) |
1652 | return true; |
1653 | |
1654 | if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x)))) |
1655 | && (REG_P (y) || (GET_CODE (y) == SUBREG |
1656 | && REG_P (SUBREG_REG (y))))) |
1657 | { |
1658 | int reg_x = -1, reg_y = -1; |
1659 | poly_int64 byte_x = 0, byte_y = 0; |
1660 | struct subreg_info info; |
1661 | |
1662 | if (GET_MODE (x) != GET_MODE (y)) |
1663 | return false; |
1664 | |
1665 | /* If we haven't done any renumbering, don't |
1666 | make any assumptions. */ |
1667 | if (reg_renumber == 0) |
1668 | return rtx_equal_p (x, y); |
1669 | |
1670 | if (code == SUBREG) |
1671 | { |
1672 | reg_x = REGNO (SUBREG_REG (x)); |
1673 | byte_x = SUBREG_BYTE (x); |
1674 | |
1675 | if (reg_renumber[reg_x] >= 0) |
1676 | { |
1677 | subreg_get_info (reg_renumber[reg_x], |
1678 | GET_MODE (SUBREG_REG (x)), byte_x, |
1679 | GET_MODE (x), &info); |
1680 | if (!info.representable_p) |
1681 | return false; |
1682 | reg_x = info.offset; |
1683 | byte_x = 0; |
1684 | } |
1685 | } |
1686 | else |
1687 | { |
1688 | reg_x = REGNO (x); |
1689 | if (reg_renumber[reg_x] >= 0) |
1690 | reg_x = reg_renumber[reg_x]; |
1691 | } |
1692 | |
1693 | if (GET_CODE (y) == SUBREG) |
1694 | { |
1695 | reg_y = REGNO (SUBREG_REG (y)); |
1696 | byte_y = SUBREG_BYTE (y); |
1697 | |
1698 | if (reg_renumber[reg_y] >= 0) |
1699 | { |
1700 | subreg_get_info (reg_renumber[reg_y], |
1701 | GET_MODE (SUBREG_REG (y)), byte_y, |
1702 | GET_MODE (y), &info); |
1703 | if (!info.representable_p) |
1704 | return false; |
1705 | reg_y = info.offset; |
1706 | byte_y = 0; |
1707 | } |
1708 | } |
1709 | else |
1710 | { |
1711 | reg_y = REGNO (y); |
1712 | if (reg_renumber[reg_y] >= 0) |
1713 | reg_y = reg_renumber[reg_y]; |
1714 | } |
1715 | |
1716 | return reg_x >= 0 && reg_x == reg_y && known_eq (byte_x, byte_y); |
1717 | } |
1718 | |
1719 | /* Now we have disposed of all the cases |
1720 | in which different rtx codes can match. */ |
1721 | if (code != GET_CODE (y)) |
1722 | return false; |
1723 | |
1724 | switch (code) |
1725 | { |
1726 | case PC: |
1727 | case ADDR_VEC: |
1728 | case ADDR_DIFF_VEC: |
1729 | CASE_CONST_UNIQUE: |
1730 | return false; |
1731 | |
1732 | case CONST_VECTOR: |
1733 | if (!same_vector_encodings_p (x, y)) |
1734 | return false; |
1735 | break; |
1736 | |
1737 | case LABEL_REF: |
1738 | /* We can't assume nonlocal labels have their following insns yet. */ |
1739 | if (LABEL_REF_NONLOCAL_P (x) || LABEL_REF_NONLOCAL_P (y)) |
1740 | return label_ref_label (ref: x) == label_ref_label (ref: y); |
1741 | |
1742 | /* Two label-refs are equivalent if they point at labels |
1743 | in the same position in the instruction stream. */ |
1744 | else |
1745 | { |
1746 | rtx_insn *xi = next_nonnote_nondebug_insn (label_ref_label (ref: x)); |
1747 | rtx_insn *yi = next_nonnote_nondebug_insn (label_ref_label (ref: y)); |
1748 | while (xi && LABEL_P (xi)) |
1749 | xi = next_nonnote_nondebug_insn (xi); |
1750 | while (yi && LABEL_P (yi)) |
1751 | yi = next_nonnote_nondebug_insn (yi); |
1752 | return xi == yi; |
1753 | } |
1754 | |
1755 | case SYMBOL_REF: |
1756 | return XSTR (x, 0) == XSTR (y, 0); |
1757 | |
1758 | case CODE_LABEL: |
1759 | /* If we didn't match EQ equality above, they aren't the same. */ |
1760 | return false; |
1761 | |
1762 | default: |
1763 | break; |
1764 | } |
1765 | |
1766 | /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ |
1767 | |
1768 | if (GET_MODE (x) != GET_MODE (y)) |
1769 | return false; |
1770 | |
1771 | /* MEMs referring to different address space are not equivalent. */ |
1772 | if (code == MEM && MEM_ADDR_SPACE (x) != MEM_ADDR_SPACE (y)) |
1773 | return false; |
1774 | |
1775 | /* For commutative operations, the RTX match if the operand match in any |
1776 | order. Also handle the simple binary and unary cases without a loop. */ |
1777 | if (targetm.commutative_p (x, UNKNOWN)) |
1778 | return ((rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) |
1779 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))) |
1780 | || (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 1)) |
1781 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 0)))); |
1782 | else if (NON_COMMUTATIVE_P (x)) |
1783 | return (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) |
1784 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))); |
1785 | else if (UNARY_P (x)) |
1786 | return rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)); |
1787 | |
1788 | /* Compare the elements. If any pair of corresponding elements |
1789 | fail to match, return false for the whole things. */ |
1790 | |
1791 | fmt = GET_RTX_FORMAT (code); |
1792 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
1793 | { |
1794 | int j; |
1795 | switch (fmt[i]) |
1796 | { |
1797 | case 'w': |
1798 | if (XWINT (x, i) != XWINT (y, i)) |
1799 | return false; |
1800 | break; |
1801 | |
1802 | case 'i': |
1803 | if (XINT (x, i) != XINT (y, i)) |
1804 | { |
1805 | if (((code == ASM_OPERANDS && i == 6) |
1806 | || (code == ASM_INPUT && i == 1))) |
1807 | break; |
1808 | return false; |
1809 | } |
1810 | break; |
1811 | |
1812 | case 'p': |
1813 | if (maybe_ne (SUBREG_BYTE (x), SUBREG_BYTE (y))) |
1814 | return false; |
1815 | break; |
1816 | |
1817 | case 't': |
1818 | if (XTREE (x, i) != XTREE (y, i)) |
1819 | return false; |
1820 | break; |
1821 | |
1822 | case 's': |
1823 | if (strcmp (XSTR (x, i), XSTR (y, i))) |
1824 | return false; |
1825 | break; |
1826 | |
1827 | case 'e': |
1828 | if (! rtx_renumbered_equal_p (XEXP (x, i), XEXP (y, i))) |
1829 | return false; |
1830 | break; |
1831 | |
1832 | case 'u': |
1833 | if (XEXP (x, i) != XEXP (y, i)) |
1834 | return false; |
1835 | /* Fall through. */ |
1836 | case '0': |
1837 | break; |
1838 | |
1839 | case 'E': |
1840 | if (XVECLEN (x, i) != XVECLEN (y, i)) |
1841 | return false; |
1842 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
1843 | if (!rtx_renumbered_equal_p (XVECEXP (x, i, j), XVECEXP (y, i, j))) |
1844 | return false; |
1845 | break; |
1846 | |
1847 | default: |
1848 | gcc_unreachable (); |
1849 | } |
1850 | } |
1851 | return true; |
1852 | } |
1853 | |
1854 | /* If X is a hard register or equivalent to one or a subregister of one, |
1855 | return the hard register number. If X is a pseudo register that was not |
1856 | assigned a hard register, return the pseudo register number. Otherwise, |
1857 | return -1. Any rtx is valid for X. */ |
1858 | |
1859 | int |
1860 | true_regnum (const_rtx x) |
1861 | { |
1862 | if (REG_P (x)) |
1863 | { |
1864 | if (REGNO (x) >= FIRST_PSEUDO_REGISTER |
1865 | && (lra_in_progress || reg_renumber[REGNO (x)] >= 0)) |
1866 | return reg_renumber[REGNO (x)]; |
1867 | return REGNO (x); |
1868 | } |
1869 | if (GET_CODE (x) == SUBREG) |
1870 | { |
1871 | int base = true_regnum (SUBREG_REG (x)); |
1872 | if (base >= 0 |
1873 | && base < FIRST_PSEUDO_REGISTER) |
1874 | { |
1875 | struct subreg_info info; |
1876 | |
1877 | subreg_get_info (lra_in_progress |
1878 | ? (unsigned) base : REGNO (SUBREG_REG (x)), |
1879 | GET_MODE (SUBREG_REG (x)), |
1880 | SUBREG_BYTE (x), GET_MODE (x), &info); |
1881 | |
1882 | if (info.representable_p) |
1883 | return base + info.offset; |
1884 | } |
1885 | } |
1886 | return -1; |
1887 | } |
1888 | |
1889 | /* Return regno of the register REG and handle subregs too. */ |
1890 | unsigned int |
1891 | reg_or_subregno (const_rtx reg) |
1892 | { |
1893 | if (GET_CODE (reg) == SUBREG) |
1894 | reg = SUBREG_REG (reg); |
1895 | gcc_assert (REG_P (reg)); |
1896 | return REGNO (reg); |
1897 | } |
1898 | |