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5924de0b | 1 | /* Optimize jump instructions, for GNU compiler. |
c773fc10 | 2 | Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997 |
5377f687 | 3 | 1998, 1999, 2000, 2001 Free Software Foundation, Inc. |
5924de0b | 4 | |
f12b58b3 | 5 | This file is part of GCC. |
5924de0b | 6 | |
f12b58b3 | 7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
5924de0b | 11 | |
f12b58b3 | 12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
5924de0b | 16 | |
17 | You should have received a copy of the GNU General Public License | |
f12b58b3 | 18 | along with GCC; see the file COPYING. If not, write to the Free |
19 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
5924de0b | 21 | |
fc4eaab7 | 22 | /* This is the pathetic reminder of old fame of the jump-optimization pass |
23 | of the compiler. Now it contains basically set of utility function to | |
24 | operate with jumps. | |
5924de0b | 25 | |
26 | Each CODE_LABEL has a count of the times it is used | |
27 | stored in the LABEL_NUSES internal field, and each JUMP_INSN | |
28 | has one label that it refers to stored in the | |
29 | JUMP_LABEL internal field. With this we can detect labels that | |
30 | become unused because of the deletion of all the jumps that | |
31 | formerly used them. The JUMP_LABEL info is sometimes looked | |
32 | at by later passes. | |
33 | ||
5924de0b | 34 | The subroutines delete_insn, redirect_jump, and invert_jump are used |
35 | from other passes as well. */ | |
36 | ||
37 | #include "config.h" | |
405711de | 38 | #include "system.h" |
5924de0b | 39 | #include "rtl.h" |
7953c610 | 40 | #include "tm_p.h" |
5924de0b | 41 | #include "flags.h" |
42 | #include "hard-reg-set.h" | |
43 | #include "regs.h" | |
5924de0b | 44 | #include "insn-config.h" |
fe3b47be | 45 | #include "insn-attr.h" |
0dbd1c74 | 46 | #include "recog.h" |
0a893c29 | 47 | #include "function.h" |
fa9157fe | 48 | #include "expr.h" |
5924de0b | 49 | #include "real.h" |
485aaaaf | 50 | #include "except.h" |
ce1fd7fc | 51 | #include "toplev.h" |
75eb327c | 52 | #include "reload.h" |
13488c51 | 53 | #include "predict.h" |
5924de0b | 54 | |
5924de0b | 55 | /* Optimize jump y; x: ... y: jumpif... x? |
56 | Don't know if it is worth bothering with. */ | |
57 | /* Optimize two cases of conditional jump to conditional jump? | |
58 | This can never delete any instruction or make anything dead, | |
59 | or even change what is live at any point. | |
60 | So perhaps let combiner do it. */ | |
61 | ||
38b9004f | 62 | static int init_label_info PARAMS ((rtx)); |
bf73fcf4 | 63 | static void mark_all_labels PARAMS ((rtx)); |
38b9004f | 64 | static int duplicate_loop_exit_test PARAMS ((rtx)); |
38b9004f | 65 | static void delete_computation PARAMS ((rtx)); |
a8b5d014 | 66 | static void redirect_exp_1 PARAMS ((rtx *, rtx, rtx, rtx)); |
ba08b7e7 | 67 | static int redirect_exp PARAMS ((rtx, rtx, rtx)); |
68 | static void invert_exp_1 PARAMS ((rtx)); | |
69 | static int invert_exp PARAMS ((rtx)); | |
38b9004f | 70 | static int returnjump_p_1 PARAMS ((rtx *, void *)); |
71 | static void delete_prior_computation PARAMS ((rtx, rtx)); | |
60ecc450 | 72 | \f |
8b946ced | 73 | /* Alternate entry into the jump optimizer. This entry point only rebuilds |
74 | the JUMP_LABEL field in jumping insns and REG_LABEL notes in non-jumping | |
75 | instructions. */ | |
76 | void | |
77 | rebuild_jump_labels (f) | |
78 | rtx f; | |
79 | { | |
19cb6b50 | 80 | rtx insn; |
5924de0b | 81 | int max_uid = 0; |
5924de0b | 82 | |
e8d75e01 | 83 | max_uid = init_label_info (f) + 1; |
5924de0b | 84 | |
bf73fcf4 | 85 | mark_all_labels (f); |
5924de0b | 86 | |
cbd914e1 | 87 | /* Keep track of labels used from static data; we don't track them |
88 | closely enough to delete them here, so make sure their reference | |
89 | count doesn't drop to zero. */ | |
5924de0b | 90 | |
91 | for (insn = forced_labels; insn; insn = XEXP (insn, 1)) | |
cbd914e1 | 92 | if (GET_CODE (XEXP (insn, 0)) == CODE_LABEL) |
93 | LABEL_NUSES (XEXP (insn, 0))++; | |
5924de0b | 94 | |
485aaaaf | 95 | /* Keep track of labels used for marking handlers for exception |
96 | regions; they cannot usually be deleted. */ | |
97 | ||
98 | for (insn = exception_handler_labels; insn; insn = XEXP (insn, 1)) | |
7d27371b | 99 | if (GET_CODE (XEXP (insn, 0)) == CODE_LABEL) |
100 | LABEL_NUSES (XEXP (insn, 0))++; | |
fc4eaab7 | 101 | } |
102 | \f | |
fb3c15bc | 103 | /* Some old code expects exactly one BARRIER as the NEXT_INSN of a |
104 | non-fallthru insn. This is not generally true, as multiple barriers | |
105 | may have crept in, or the BARRIER may be separated from the last | |
106 | real insn by one or more NOTEs. | |
107 | ||
108 | This simple pass moves barriers and removes duplicates so that the | |
109 | old code is happy. | |
110 | */ | |
111 | void | |
112 | cleanup_barriers () | |
113 | { | |
114 | rtx insn, next, prev; | |
115 | for (insn = get_insns (); insn; insn = next) | |
116 | { | |
117 | next = NEXT_INSN (insn); | |
118 | if (GET_CODE (insn) == BARRIER) | |
119 | { | |
120 | prev = prev_nonnote_insn (insn); | |
121 | if (GET_CODE (prev) == BARRIER) | |
122 | delete_barrier (insn); | |
123 | else if (prev != PREV_INSN (insn)) | |
124 | reorder_insns (insn, insn, prev); | |
125 | } | |
126 | } | |
127 | } | |
128 | \f | |
fc4eaab7 | 129 | void |
130 | copy_loop_headers (f) | |
131 | rtx f; | |
132 | { | |
19cb6b50 | 133 | rtx insn, next; |
5924de0b | 134 | /* Now iterate optimizing jumps until nothing changes over one pass. */ |
fc4eaab7 | 135 | for (insn = f; insn; insn = next) |
5924de0b | 136 | { |
fc4eaab7 | 137 | rtx temp, temp1; |
5924de0b | 138 | |
fc4eaab7 | 139 | next = NEXT_INSN (insn); |
7014838c | 140 | |
fc4eaab7 | 141 | /* See if this is a NOTE_INSN_LOOP_BEG followed by an unconditional |
142 | jump. Try to optimize by duplicating the loop exit test if so. | |
143 | This is only safe immediately after regscan, because it uses | |
144 | the values of regno_first_uid and regno_last_uid. */ | |
145 | if (GET_CODE (insn) == NOTE | |
146 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG | |
147 | && (temp1 = next_nonnote_insn (insn)) != 0 | |
148 | && any_uncondjump_p (temp1) && onlyjump_p (temp1)) | |
149 | { | |
150 | temp = PREV_INSN (insn); | |
151 | if (duplicate_loop_exit_test (insn)) | |
5924de0b | 152 | { |
fc4eaab7 | 153 | next = NEXT_INSN (temp); |
5924de0b | 154 | } |
5924de0b | 155 | } |
5924de0b | 156 | } |
fc4eaab7 | 157 | } |
5924de0b | 158 | |
fc4eaab7 | 159 | void |
160 | purge_line_number_notes (f) | |
161 | rtx f; | |
162 | { | |
163 | rtx last_note = 0; | |
164 | rtx insn; | |
5924de0b | 165 | /* Delete extraneous line number notes. |
166 | Note that two consecutive notes for different lines are not really | |
167 | extraneous. There should be some indication where that line belonged, | |
168 | even if it became empty. */ | |
169 | ||
fc4eaab7 | 170 | for (insn = f; insn; insn = NEXT_INSN (insn)) |
171 | if (GET_CODE (insn) == NOTE) | |
172 | { | |
173 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG) | |
174 | /* Any previous line note was for the prologue; gdb wants a new | |
175 | note after the prologue even if it is for the same line. */ | |
176 | last_note = NULL_RTX; | |
177 | else if (NOTE_LINE_NUMBER (insn) >= 0) | |
178 | { | |
179 | /* Delete this note if it is identical to previous note. */ | |
180 | if (last_note | |
181 | && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last_note) | |
182 | && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last_note)) | |
183 | { | |
e4bf866d | 184 | delete_related_insns (insn); |
fc4eaab7 | 185 | continue; |
186 | } | |
5924de0b | 187 | |
fc4eaab7 | 188 | last_note = insn; |
189 | } | |
190 | } | |
e8d75e01 | 191 | } |
192 | \f | |
193 | /* Initialize LABEL_NUSES and JUMP_LABEL fields. Delete any REG_LABEL | |
194 | notes whose labels don't occur in the insn any more. Returns the | |
195 | largest INSN_UID found. */ | |
196 | static int | |
197 | init_label_info (f) | |
198 | rtx f; | |
199 | { | |
200 | int largest_uid = 0; | |
201 | rtx insn; | |
202 | ||
203 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
204 | { | |
205 | if (GET_CODE (insn) == CODE_LABEL) | |
206 | LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0); | |
207 | else if (GET_CODE (insn) == JUMP_INSN) | |
208 | JUMP_LABEL (insn) = 0; | |
209 | else if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
210 | { | |
211 | rtx note, next; | |
212 | ||
213 | for (note = REG_NOTES (insn); note; note = next) | |
214 | { | |
215 | next = XEXP (note, 1); | |
216 | if (REG_NOTE_KIND (note) == REG_LABEL | |
217 | && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn))) | |
218 | remove_note (insn, note); | |
219 | } | |
220 | } | |
221 | if (INSN_UID (insn) > largest_uid) | |
222 | largest_uid = INSN_UID (insn); | |
223 | } | |
224 | ||
225 | return largest_uid; | |
226 | } | |
227 | ||
e8d75e01 | 228 | /* Mark the label each jump jumps to. |
fc4eaab7 | 229 | Combine consecutive labels, and count uses of labels. */ |
e8d75e01 | 230 | |
231 | static void | |
bf73fcf4 | 232 | mark_all_labels (f) |
e8d75e01 | 233 | rtx f; |
e8d75e01 | 234 | { |
235 | rtx insn; | |
236 | ||
237 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
9204e736 | 238 | if (INSN_P (insn)) |
e8d75e01 | 239 | { |
0e3150ce | 240 | if (GET_CODE (insn) == CALL_INSN |
241 | && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) | |
242 | { | |
bf73fcf4 | 243 | mark_all_labels (XEXP (PATTERN (insn), 0)); |
244 | mark_all_labels (XEXP (PATTERN (insn), 1)); | |
245 | mark_all_labels (XEXP (PATTERN (insn), 2)); | |
af29e037 | 246 | |
247 | /* Canonicalize the tail recursion label attached to the | |
248 | CALL_PLACEHOLDER insn. */ | |
249 | if (XEXP (PATTERN (insn), 3)) | |
250 | { | |
251 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
252 | XEXP (PATTERN (insn), 3)); | |
bf73fcf4 | 253 | mark_jump_label (label_ref, insn, 0); |
af29e037 | 254 | XEXP (PATTERN (insn), 3) = XEXP (label_ref, 0); |
255 | } | |
256 | ||
0e3150ce | 257 | continue; |
258 | } | |
7113a566 | 259 | |
bf73fcf4 | 260 | mark_jump_label (PATTERN (insn), insn, 0); |
e8d75e01 | 261 | if (! INSN_DELETED_P (insn) && GET_CODE (insn) == JUMP_INSN) |
262 | { | |
d3ff0f75 | 263 | /* When we know the LABEL_REF contained in a REG used in |
264 | an indirect jump, we'll have a REG_LABEL note so that | |
265 | flow can tell where it's going. */ | |
266 | if (JUMP_LABEL (insn) == 0) | |
267 | { | |
268 | rtx label_note = find_reg_note (insn, REG_LABEL, NULL_RTX); | |
269 | if (label_note) | |
270 | { | |
271 | /* But a LABEL_REF around the REG_LABEL note, so | |
272 | that we can canonicalize it. */ | |
273 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
274 | XEXP (label_note, 0)); | |
275 | ||
bf73fcf4 | 276 | mark_jump_label (label_ref, insn, 0); |
d3ff0f75 | 277 | XEXP (label_note, 0) = XEXP (label_ref, 0); |
278 | JUMP_LABEL (insn) = XEXP (label_note, 0); | |
279 | } | |
280 | } | |
e8d75e01 | 281 | } |
282 | } | |
283 | } | |
284 | ||
5924de0b | 285 | /* LOOP_START is a NOTE_INSN_LOOP_BEG note that is followed by an unconditional |
286 | jump. Assume that this unconditional jump is to the exit test code. If | |
287 | the code is sufficiently simple, make a copy of it before INSN, | |
288 | followed by a jump to the exit of the loop. Then delete the unconditional | |
289 | jump after INSN. | |
290 | ||
5924de0b | 291 | Return 1 if we made the change, else 0. |
292 | ||
293 | This is only safe immediately after a regscan pass because it uses the | |
294 | values of regno_first_uid and regno_last_uid. */ | |
295 | ||
296 | static int | |
297 | duplicate_loop_exit_test (loop_start) | |
298 | rtx loop_start; | |
299 | { | |
3a348c93 | 300 | rtx insn, set, reg, p, link; |
4e717234 | 301 | rtx copy = 0, first_copy = 0; |
5924de0b | 302 | int num_insns = 0; |
303 | rtx exitcode = NEXT_INSN (JUMP_LABEL (next_nonnote_insn (loop_start))); | |
304 | rtx lastexit; | |
305 | int max_reg = max_reg_num (); | |
306 | rtx *reg_map = 0; | |
ea918419 | 307 | rtx loop_pre_header_label; |
5924de0b | 308 | |
309 | /* Scan the exit code. We do not perform this optimization if any insn: | |
310 | ||
311 | is a CALL_INSN | |
312 | is a CODE_LABEL | |
313 | has a REG_RETVAL or REG_LIBCALL note (hard to adjust) | |
314 | is a NOTE_INSN_LOOP_BEG because this means we have a nested loop | |
315 | is a NOTE_INSN_BLOCK_{BEG,END} because duplicating these notes | |
7665c376 | 316 | is not valid. |
17b1950c | 317 | |
318 | We also do not do this if we find an insn with ASM_OPERANDS. While | |
319 | this restriction should not be necessary, copying an insn with | |
320 | ASM_OPERANDS can confuse asm_noperands in some cases. | |
5924de0b | 321 | |
322 | Also, don't do this if the exit code is more than 20 insns. */ | |
323 | ||
324 | for (insn = exitcode; | |
325 | insn | |
326 | && ! (GET_CODE (insn) == NOTE | |
327 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END); | |
328 | insn = NEXT_INSN (insn)) | |
329 | { | |
330 | switch (GET_CODE (insn)) | |
331 | { | |
332 | case CODE_LABEL: | |
333 | case CALL_INSN: | |
334 | return 0; | |
335 | case NOTE: | |
801acb81 | 336 | /* We could be in front of the wrong NOTE_INSN_LOOP_END if there is |
337 | a jump immediately after the loop start that branches outside | |
338 | the loop but within an outer loop, near the exit test. | |
339 | If we copied this exit test and created a phony | |
340 | NOTE_INSN_LOOP_VTOP, this could make instructions immediately | |
341 | before the exit test look like these could be safely moved | |
342 | out of the loop even if they actually may be never executed. | |
343 | This can be avoided by checking here for NOTE_INSN_LOOP_CONT. */ | |
344 | ||
5924de0b | 345 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG |
801acb81 | 346 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT) |
5924de0b | 347 | return 0; |
ec6be638 | 348 | |
349 | if (optimize < 2 | |
350 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
351 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)) | |
352 | /* If we were to duplicate this code, we would not move | |
353 | the BLOCK notes, and so debugging the moved code would | |
354 | be difficult. Thus, we only move the code with -O2 or | |
355 | higher. */ | |
356 | return 0; | |
357 | ||
5924de0b | 358 | break; |
359 | case JUMP_INSN: | |
360 | case INSN: | |
7665c376 | 361 | /* The code below would grossly mishandle REG_WAS_0 notes, |
362 | so get rid of them here. */ | |
363 | while ((p = find_reg_note (insn, REG_WAS_0, NULL_RTX)) != 0) | |
364 | remove_note (insn, p); | |
5924de0b | 365 | if (++num_insns > 20 |
1bb04728 | 366 | || find_reg_note (insn, REG_RETVAL, NULL_RTX) |
928d57e3 | 367 | || find_reg_note (insn, REG_LIBCALL, NULL_RTX)) |
5924de0b | 368 | return 0; |
369 | break; | |
0dbd1c74 | 370 | default: |
371 | break; | |
5924de0b | 372 | } |
373 | } | |
374 | ||
375 | /* Unless INSN is zero, we can do the optimization. */ | |
376 | if (insn == 0) | |
377 | return 0; | |
378 | ||
379 | lastexit = insn; | |
380 | ||
381 | /* See if any insn sets a register only used in the loop exit code and | |
382 | not a user variable. If so, replace it with a new register. */ | |
383 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
384 | if (GET_CODE (insn) == INSN | |
385 | && (set = single_set (insn)) != 0 | |
3a348c93 | 386 | && ((reg = SET_DEST (set), GET_CODE (reg) == REG) |
387 | || (GET_CODE (reg) == SUBREG | |
388 | && (reg = SUBREG_REG (reg), GET_CODE (reg) == REG))) | |
389 | && REGNO (reg) >= FIRST_PSEUDO_REGISTER | |
394685a4 | 390 | && REGNO_FIRST_UID (REGNO (reg)) == INSN_UID (insn)) |
5924de0b | 391 | { |
392 | for (p = NEXT_INSN (insn); p != lastexit; p = NEXT_INSN (p)) | |
394685a4 | 393 | if (REGNO_LAST_UID (REGNO (reg)) == INSN_UID (p)) |
5924de0b | 394 | break; |
395 | ||
396 | if (p != lastexit) | |
397 | { | |
398 | /* We can do the replacement. Allocate reg_map if this is the | |
399 | first replacement we found. */ | |
400 | if (reg_map == 0) | |
8b861be4 | 401 | reg_map = (rtx *) xcalloc (max_reg, sizeof (rtx)); |
5924de0b | 402 | |
3a348c93 | 403 | REG_LOOP_TEST_P (reg) = 1; |
5924de0b | 404 | |
3a348c93 | 405 | reg_map[REGNO (reg)] = gen_reg_rtx (GET_MODE (reg)); |
5924de0b | 406 | } |
407 | } | |
ea918419 | 408 | loop_pre_header_label = gen_label_rtx (); |
5924de0b | 409 | |
410 | /* Now copy each insn. */ | |
411 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
4e717234 | 412 | { |
413 | switch (GET_CODE (insn)) | |
414 | { | |
415 | case BARRIER: | |
416 | copy = emit_barrier_before (loop_start); | |
417 | break; | |
418 | case NOTE: | |
419 | /* Only copy line-number notes. */ | |
420 | if (NOTE_LINE_NUMBER (insn) >= 0) | |
421 | { | |
422 | copy = emit_note_before (NOTE_LINE_NUMBER (insn), loop_start); | |
423 | NOTE_SOURCE_FILE (copy) = NOTE_SOURCE_FILE (insn); | |
424 | } | |
425 | break; | |
7113a566 | 426 | |
4e717234 | 427 | case INSN: |
928d57e3 | 428 | copy = emit_insn_before (copy_insn (PATTERN (insn)), loop_start); |
4e717234 | 429 | if (reg_map) |
430 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
7113a566 | 431 | |
bf73fcf4 | 432 | mark_jump_label (PATTERN (copy), copy, 0); |
7113a566 | 433 | |
4e717234 | 434 | /* Copy all REG_NOTES except REG_LABEL since mark_jump_label will |
435 | make them. */ | |
436 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
437 | if (REG_NOTE_KIND (link) != REG_LABEL) | |
74b0991d | 438 | { |
439 | if (GET_CODE (link) == EXPR_LIST) | |
440 | REG_NOTES (copy) | |
441 | = copy_insn_1 (gen_rtx_EXPR_LIST (REG_NOTE_KIND (link), | |
442 | XEXP (link, 0), | |
443 | REG_NOTES (copy))); | |
444 | else | |
445 | REG_NOTES (copy) | |
446 | = copy_insn_1 (gen_rtx_INSN_LIST (REG_NOTE_KIND (link), | |
447 | XEXP (link, 0), | |
448 | REG_NOTES (copy))); | |
449 | } | |
450 | ||
4e717234 | 451 | if (reg_map && REG_NOTES (copy)) |
452 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
453 | break; | |
7113a566 | 454 | |
4e717234 | 455 | case JUMP_INSN: |
7113a566 | 456 | copy = emit_jump_insn_before (copy_insn (PATTERN (insn)), |
457 | loop_start); | |
4e717234 | 458 | if (reg_map) |
459 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
bf73fcf4 | 460 | mark_jump_label (PATTERN (copy), copy, 0); |
4e717234 | 461 | if (REG_NOTES (insn)) |
462 | { | |
928d57e3 | 463 | REG_NOTES (copy) = copy_insn_1 (REG_NOTES (insn)); |
4e717234 | 464 | if (reg_map) |
465 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
466 | } | |
7113a566 | 467 | |
13488c51 | 468 | /* Predict conditional jump that do make loop looping as taken. |
469 | Other jumps are probably exit conditions, so predict | |
470 | them as untaken. */ | |
471 | if (any_condjump_p (copy)) | |
472 | { | |
473 | rtx label = JUMP_LABEL (copy); | |
474 | if (label) | |
475 | { | |
4361b500 | 476 | /* The jump_insn after loop_start should be followed |
477 | by barrier and loopback label. */ | |
478 | if (prev_nonnote_insn (label) | |
ea918419 | 479 | && (prev_nonnote_insn (prev_nonnote_insn (label)) |
480 | == next_nonnote_insn (loop_start))) | |
481 | { | |
482 | predict_insn_def (copy, PRED_LOOP_HEADER, TAKEN); | |
483 | /* To keep pre-header, we need to redirect all loop | |
484 | entrances before the LOOP_BEG note. */ | |
485 | redirect_jump (copy, loop_pre_header_label, 0); | |
486 | } | |
13488c51 | 487 | else |
488 | predict_insn_def (copy, PRED_LOOP_HEADER, NOT_TAKEN); | |
489 | } | |
490 | } | |
4e717234 | 491 | break; |
7113a566 | 492 | |
4e717234 | 493 | default: |
494 | abort (); | |
495 | } | |
5924de0b | 496 | |
4e717234 | 497 | /* Record the first insn we copied. We need it so that we can |
498 | scan the copied insns for new pseudo registers. */ | |
499 | if (! first_copy) | |
500 | first_copy = copy; | |
501 | } | |
5924de0b | 502 | |
503 | /* Now clean up by emitting a jump to the end label and deleting the jump | |
504 | at the start of the loop. */ | |
b8778d98 | 505 | if (! copy || GET_CODE (copy) != BARRIER) |
5924de0b | 506 | { |
507 | copy = emit_jump_insn_before (gen_jump (get_label_after (insn)), | |
508 | loop_start); | |
4e717234 | 509 | |
510 | /* Record the first insn we copied. We need it so that we can | |
511 | scan the copied insns for new pseudo registers. This may not | |
512 | be strictly necessary since we should have copied at least one | |
513 | insn above. But I am going to be safe. */ | |
514 | if (! first_copy) | |
515 | first_copy = copy; | |
516 | ||
bf73fcf4 | 517 | mark_jump_label (PATTERN (copy), copy, 0); |
5924de0b | 518 | emit_barrier_before (loop_start); |
519 | } | |
520 | ||
ea918419 | 521 | emit_label_before (loop_pre_header_label, loop_start); |
522 | ||
4e717234 | 523 | /* Now scan from the first insn we copied to the last insn we copied |
524 | (copy) for new pseudo registers. Do this after the code to jump to | |
525 | the end label since that might create a new pseudo too. */ | |
526 | reg_scan_update (first_copy, copy, max_reg); | |
527 | ||
5924de0b | 528 | /* Mark the exit code as the virtual top of the converted loop. */ |
529 | emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode); | |
530 | ||
e4bf866d | 531 | delete_related_insns (next_nonnote_insn (loop_start)); |
7113a566 | 532 | |
8b861be4 | 533 | /* Clean up. */ |
534 | if (reg_map) | |
535 | free (reg_map); | |
92d3c3ad | 536 | |
5924de0b | 537 | return 1; |
538 | } | |
539 | \f | |
74b0991d | 540 | /* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-end, |
3612339f | 541 | notes between START and END out before START. START and END may be such |
542 | notes. Returns the values of the new starting and ending insns, which | |
87dc0300 | 543 | may be different if the original ones were such notes. |
544 | Return true if there were only such notes and no real instructions. */ | |
5924de0b | 545 | |
87dc0300 | 546 | bool |
3612339f | 547 | squeeze_notes (startp, endp) |
548 | rtx* startp; | |
549 | rtx* endp; | |
5924de0b | 550 | { |
3612339f | 551 | rtx start = *startp; |
552 | rtx end = *endp; | |
553 | ||
5924de0b | 554 | rtx insn; |
555 | rtx next; | |
3612339f | 556 | rtx last = NULL; |
557 | rtx past_end = NEXT_INSN (end); | |
5924de0b | 558 | |
3612339f | 559 | for (insn = start; insn != past_end; insn = next) |
5924de0b | 560 | { |
561 | next = NEXT_INSN (insn); | |
562 | if (GET_CODE (insn) == NOTE | |
563 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END | |
564 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
565 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG | |
566 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END | |
567 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT | |
a196d160 | 568 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_VTOP)) |
5924de0b | 569 | { |
d2d45541 | 570 | if (insn == start) |
571 | start = next; | |
572 | else | |
573 | { | |
574 | rtx prev = PREV_INSN (insn); | |
575 | PREV_INSN (insn) = PREV_INSN (start); | |
576 | NEXT_INSN (insn) = start; | |
577 | NEXT_INSN (PREV_INSN (insn)) = insn; | |
578 | PREV_INSN (NEXT_INSN (insn)) = insn; | |
579 | NEXT_INSN (prev) = next; | |
580 | PREV_INSN (next) = prev; | |
581 | } | |
5924de0b | 582 | } |
3612339f | 583 | else |
584 | last = insn; | |
5924de0b | 585 | } |
d2d45541 | 586 | |
87dc0300 | 587 | /* There were no real instructions. */ |
3612339f | 588 | if (start == past_end) |
87dc0300 | 589 | return true; |
3612339f | 590 | |
591 | end = last; | |
592 | ||
593 | *startp = start; | |
594 | *endp = end; | |
87dc0300 | 595 | return false; |
5924de0b | 596 | } |
597 | \f | |
5924de0b | 598 | /* Return the label before INSN, or put a new label there. */ |
599 | ||
600 | rtx | |
601 | get_label_before (insn) | |
602 | rtx insn; | |
603 | { | |
604 | rtx label; | |
605 | ||
606 | /* Find an existing label at this point | |
607 | or make a new one if there is none. */ | |
608 | label = prev_nonnote_insn (insn); | |
609 | ||
610 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
611 | { | |
612 | rtx prev = PREV_INSN (insn); | |
613 | ||
5924de0b | 614 | label = gen_label_rtx (); |
615 | emit_label_after (label, prev); | |
616 | LABEL_NUSES (label) = 0; | |
617 | } | |
618 | return label; | |
619 | } | |
620 | ||
621 | /* Return the label after INSN, or put a new label there. */ | |
622 | ||
623 | rtx | |
624 | get_label_after (insn) | |
625 | rtx insn; | |
626 | { | |
627 | rtx label; | |
628 | ||
629 | /* Find an existing label at this point | |
630 | or make a new one if there is none. */ | |
631 | label = next_nonnote_insn (insn); | |
632 | ||
633 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
634 | { | |
5924de0b | 635 | label = gen_label_rtx (); |
636 | emit_label_after (label, insn); | |
637 | LABEL_NUSES (label) = 0; | |
638 | } | |
639 | return label; | |
640 | } | |
641 | \f | |
fa8b3d85 | 642 | /* Given a comparison (CODE ARG0 ARG1), inside an insn, INSN, return a code |
8e98892d | 643 | of reversed comparison if it is possible to do so. Otherwise return UNKNOWN. |
644 | UNKNOWN may be returned in case we are having CC_MODE compare and we don't | |
645 | know whether it's source is floating point or integer comparison. Machine | |
646 | description should define REVERSIBLE_CC_MODE and REVERSE_CONDITION macros | |
647 | to help this function avoid overhead in these cases. */ | |
648 | enum rtx_code | |
649 | reversed_comparison_code_parts (code, arg0, arg1, insn) | |
650 | rtx insn, arg0, arg1; | |
651 | enum rtx_code code; | |
5924de0b | 652 | { |
8e98892d | 653 | enum machine_mode mode; |
5924de0b | 654 | |
655 | /* If this is not actually a comparison, we can't reverse it. */ | |
8e98892d | 656 | if (GET_RTX_CLASS (code) != '<') |
657 | return UNKNOWN; | |
658 | ||
659 | mode = GET_MODE (arg0); | |
660 | if (mode == VOIDmode) | |
661 | mode = GET_MODE (arg1); | |
662 | ||
663 | /* First see if machine description supply us way to reverse the comparison. | |
664 | Give it priority over everything else to allow machine description to do | |
665 | tricks. */ | |
666 | #ifdef REVERSIBLE_CC_MODE | |
0ec244e1 | 667 | if (GET_MODE_CLASS (mode) == MODE_CC |
8e98892d | 668 | && REVERSIBLE_CC_MODE (mode)) |
669 | { | |
670 | #ifdef REVERSE_CONDITION | |
85fc0ad1 | 671 | return REVERSE_CONDITION (code, mode); |
8e98892d | 672 | #endif |
85fc0ad1 | 673 | return reverse_condition (code); |
674 | } | |
8e98892d | 675 | #endif |
5924de0b | 676 | |
fa8b3d85 | 677 | /* Try a few special cases based on the comparison code. */ |
8e98892d | 678 | switch (code) |
679 | { | |
85fc0ad1 | 680 | case GEU: |
681 | case GTU: | |
682 | case LEU: | |
683 | case LTU: | |
684 | case NE: | |
685 | case EQ: | |
686 | /* It is always safe to reverse EQ and NE, even for the floating | |
687 | point. Similary the unsigned comparisons are never used for | |
688 | floating point so we can reverse them in the default way. */ | |
689 | return reverse_condition (code); | |
690 | case ORDERED: | |
691 | case UNORDERED: | |
692 | case LTGT: | |
693 | case UNEQ: | |
694 | /* In case we already see unordered comparison, we can be sure to | |
695 | be dealing with floating point so we don't need any more tests. */ | |
696 | return reverse_condition_maybe_unordered (code); | |
697 | case UNLT: | |
698 | case UNLE: | |
699 | case UNGT: | |
700 | case UNGE: | |
701 | /* We don't have safe way to reverse these yet. */ | |
702 | return UNKNOWN; | |
703 | default: | |
704 | break; | |
8e98892d | 705 | } |
706 | ||
707 | /* In case we give up IEEE compatibility, all comparisons are reversible. */ | |
5924de0b | 708 | if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT |
7f3be425 | 709 | || flag_unsafe_math_optimizations) |
8e98892d | 710 | return reverse_condition (code); |
711 | ||
712 | if (GET_MODE_CLASS (mode) == MODE_CC | |
5924de0b | 713 | #ifdef HAVE_cc0 |
714 | || arg0 == cc0_rtx | |
715 | #endif | |
716 | ) | |
717 | { | |
8e98892d | 718 | rtx prev; |
719 | /* Try to search for the comparison to determine the real mode. | |
720 | This code is expensive, but with sane machine description it | |
721 | will be never used, since REVERSIBLE_CC_MODE will return true | |
722 | in all cases. */ | |
111f2389 | 723 | if (! insn) |
8e98892d | 724 | return UNKNOWN; |
7113a566 | 725 | |
7014838c | 726 | for (prev = prev_nonnote_insn (insn); |
727 | prev != 0 && GET_CODE (prev) != CODE_LABEL; | |
728 | prev = prev_nonnote_insn (prev)) | |
8e98892d | 729 | { |
730 | rtx set = set_of (arg0, prev); | |
731 | if (set && GET_CODE (set) == SET | |
732 | && rtx_equal_p (SET_DEST (set), arg0)) | |
733 | { | |
734 | rtx src = SET_SRC (set); | |
5924de0b | 735 | |
8e98892d | 736 | if (GET_CODE (src) == COMPARE) |
737 | { | |
738 | rtx comparison = src; | |
739 | arg0 = XEXP (src, 0); | |
740 | mode = GET_MODE (arg0); | |
741 | if (mode == VOIDmode) | |
742 | mode = GET_MODE (XEXP (comparison, 1)); | |
743 | break; | |
744 | } | |
dd5b4b36 | 745 | /* We can get past reg-reg moves. This may be useful for model |
8e98892d | 746 | of i387 comparisons that first move flag registers around. */ |
747 | if (REG_P (src)) | |
748 | { | |
749 | arg0 = src; | |
750 | continue; | |
751 | } | |
752 | } | |
753 | /* If register is clobbered in some ununderstandable way, | |
754 | give up. */ | |
755 | if (set) | |
756 | return UNKNOWN; | |
757 | } | |
5924de0b | 758 | } |
759 | ||
8e98892d | 760 | /* An integer condition. */ |
761 | if (GET_CODE (arg0) == CONST_INT | |
762 | || (GET_MODE (arg0) != VOIDmode | |
763 | && GET_MODE_CLASS (mode) != MODE_CC | |
764 | && ! FLOAT_MODE_P (mode))) | |
765 | return reverse_condition (code); | |
766 | ||
767 | return UNKNOWN; | |
768 | } | |
769 | ||
770 | /* An wrapper around the previous function to take COMPARISON as rtx | |
771 | expression. This simplifies many callers. */ | |
772 | enum rtx_code | |
773 | reversed_comparison_code (comparison, insn) | |
774 | rtx comparison, insn; | |
775 | { | |
776 | if (GET_RTX_CLASS (GET_CODE (comparison)) != '<') | |
777 | return UNKNOWN; | |
778 | return reversed_comparison_code_parts (GET_CODE (comparison), | |
779 | XEXP (comparison, 0), | |
780 | XEXP (comparison, 1), insn); | |
781 | } | |
782 | \f | |
a4110d9a | 783 | /* Given an rtx-code for a comparison, return the code for the negated |
784 | comparison. If no such code exists, return UNKNOWN. | |
785 | ||
786 | WATCH OUT! reverse_condition is not safe to use on a jump that might | |
787 | be acting on the results of an IEEE floating point comparison, because | |
7113a566 | 788 | of the special treatment of non-signaling nans in comparisons. |
8e98892d | 789 | Use reversed_comparison_code instead. */ |
5924de0b | 790 | |
791 | enum rtx_code | |
792 | reverse_condition (code) | |
793 | enum rtx_code code; | |
794 | { | |
795 | switch (code) | |
796 | { | |
797 | case EQ: | |
798 | return NE; | |
5924de0b | 799 | case NE: |
800 | return EQ; | |
5924de0b | 801 | case GT: |
802 | return LE; | |
5924de0b | 803 | case GE: |
804 | return LT; | |
5924de0b | 805 | case LT: |
806 | return GE; | |
5924de0b | 807 | case LE: |
808 | return GT; | |
5924de0b | 809 | case GTU: |
810 | return LEU; | |
5924de0b | 811 | case GEU: |
812 | return LTU; | |
5924de0b | 813 | case LTU: |
814 | return GEU; | |
5924de0b | 815 | case LEU: |
816 | return GTU; | |
a4110d9a | 817 | case UNORDERED: |
818 | return ORDERED; | |
819 | case ORDERED: | |
820 | return UNORDERED; | |
821 | ||
822 | case UNLT: | |
823 | case UNLE: | |
824 | case UNGT: | |
825 | case UNGE: | |
826 | case UNEQ: | |
79777bad | 827 | case LTGT: |
a4110d9a | 828 | return UNKNOWN; |
5924de0b | 829 | |
830 | default: | |
831 | abort (); | |
5924de0b | 832 | } |
833 | } | |
834 | ||
79777bad | 835 | /* Similar, but we're allowed to generate unordered comparisons, which |
836 | makes it safe for IEEE floating-point. Of course, we have to recognize | |
837 | that the target will support them too... */ | |
838 | ||
839 | enum rtx_code | |
840 | reverse_condition_maybe_unordered (code) | |
841 | enum rtx_code code; | |
842 | { | |
843 | /* Non-IEEE formats don't have unordered conditions. */ | |
844 | if (TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT) | |
845 | return reverse_condition (code); | |
846 | ||
847 | switch (code) | |
848 | { | |
849 | case EQ: | |
850 | return NE; | |
851 | case NE: | |
852 | return EQ; | |
853 | case GT: | |
854 | return UNLE; | |
855 | case GE: | |
856 | return UNLT; | |
857 | case LT: | |
858 | return UNGE; | |
859 | case LE: | |
860 | return UNGT; | |
861 | case LTGT: | |
862 | return UNEQ; | |
79777bad | 863 | case UNORDERED: |
864 | return ORDERED; | |
865 | case ORDERED: | |
866 | return UNORDERED; | |
867 | case UNLT: | |
868 | return GE; | |
869 | case UNLE: | |
870 | return GT; | |
871 | case UNGT: | |
872 | return LE; | |
873 | case UNGE: | |
874 | return LT; | |
875 | case UNEQ: | |
876 | return LTGT; | |
877 | ||
878 | default: | |
879 | abort (); | |
880 | } | |
881 | } | |
882 | ||
5924de0b | 883 | /* Similar, but return the code when two operands of a comparison are swapped. |
884 | This IS safe for IEEE floating-point. */ | |
885 | ||
886 | enum rtx_code | |
887 | swap_condition (code) | |
888 | enum rtx_code code; | |
889 | { | |
890 | switch (code) | |
891 | { | |
892 | case EQ: | |
893 | case NE: | |
a4110d9a | 894 | case UNORDERED: |
895 | case ORDERED: | |
896 | case UNEQ: | |
79777bad | 897 | case LTGT: |
5924de0b | 898 | return code; |
899 | ||
900 | case GT: | |
901 | return LT; | |
5924de0b | 902 | case GE: |
903 | return LE; | |
5924de0b | 904 | case LT: |
905 | return GT; | |
5924de0b | 906 | case LE: |
907 | return GE; | |
5924de0b | 908 | case GTU: |
909 | return LTU; | |
5924de0b | 910 | case GEU: |
911 | return LEU; | |
5924de0b | 912 | case LTU: |
913 | return GTU; | |
5924de0b | 914 | case LEU: |
915 | return GEU; | |
a4110d9a | 916 | case UNLT: |
917 | return UNGT; | |
918 | case UNLE: | |
919 | return UNGE; | |
920 | case UNGT: | |
921 | return UNLT; | |
922 | case UNGE: | |
923 | return UNLE; | |
924 | ||
5924de0b | 925 | default: |
926 | abort (); | |
5924de0b | 927 | } |
928 | } | |
929 | ||
930 | /* Given a comparison CODE, return the corresponding unsigned comparison. | |
931 | If CODE is an equality comparison or already an unsigned comparison, | |
932 | CODE is returned. */ | |
933 | ||
934 | enum rtx_code | |
935 | unsigned_condition (code) | |
936 | enum rtx_code code; | |
937 | { | |
938 | switch (code) | |
939 | { | |
940 | case EQ: | |
941 | case NE: | |
942 | case GTU: | |
943 | case GEU: | |
944 | case LTU: | |
945 | case LEU: | |
946 | return code; | |
947 | ||
948 | case GT: | |
949 | return GTU; | |
5924de0b | 950 | case GE: |
951 | return GEU; | |
5924de0b | 952 | case LT: |
953 | return LTU; | |
5924de0b | 954 | case LE: |
955 | return LEU; | |
956 | ||
957 | default: | |
958 | abort (); | |
959 | } | |
960 | } | |
961 | ||
962 | /* Similarly, return the signed version of a comparison. */ | |
963 | ||
964 | enum rtx_code | |
965 | signed_condition (code) | |
966 | enum rtx_code code; | |
967 | { | |
968 | switch (code) | |
969 | { | |
970 | case EQ: | |
971 | case NE: | |
972 | case GT: | |
973 | case GE: | |
974 | case LT: | |
975 | case LE: | |
976 | return code; | |
977 | ||
978 | case GTU: | |
979 | return GT; | |
5924de0b | 980 | case GEU: |
981 | return GE; | |
5924de0b | 982 | case LTU: |
983 | return LT; | |
5924de0b | 984 | case LEU: |
985 | return LE; | |
986 | ||
987 | default: | |
988 | abort (); | |
989 | } | |
990 | } | |
991 | \f | |
992 | /* Return non-zero if CODE1 is more strict than CODE2, i.e., if the | |
993 | truth of CODE1 implies the truth of CODE2. */ | |
994 | ||
995 | int | |
996 | comparison_dominates_p (code1, code2) | |
997 | enum rtx_code code1, code2; | |
998 | { | |
ca7744c6 | 999 | /* UNKNOWN comparison codes can happen as a result of trying to revert |
1000 | comparison codes. | |
1001 | They can't match anything, so we have to reject them here. */ | |
1002 | if (code1 == UNKNOWN || code2 == UNKNOWN) | |
1003 | return 0; | |
1004 | ||
5924de0b | 1005 | if (code1 == code2) |
1006 | return 1; | |
1007 | ||
1008 | switch (code1) | |
1009 | { | |
5aa3f5e2 | 1010 | case UNEQ: |
1011 | if (code2 == UNLE || code2 == UNGE) | |
1012 | return 1; | |
1013 | break; | |
1014 | ||
5924de0b | 1015 | case EQ: |
79777bad | 1016 | if (code2 == LE || code2 == LEU || code2 == GE || code2 == GEU |
1017 | || code2 == ORDERED) | |
5924de0b | 1018 | return 1; |
1019 | break; | |
1020 | ||
5aa3f5e2 | 1021 | case UNLT: |
1022 | if (code2 == UNLE || code2 == NE) | |
1023 | return 1; | |
1024 | break; | |
1025 | ||
5924de0b | 1026 | case LT: |
5aa3f5e2 | 1027 | if (code2 == LE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
1028 | return 1; | |
1029 | break; | |
1030 | ||
1031 | case UNGT: | |
1032 | if (code2 == UNGE || code2 == NE) | |
5924de0b | 1033 | return 1; |
1034 | break; | |
1035 | ||
1036 | case GT: | |
5aa3f5e2 | 1037 | if (code2 == GE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
79777bad | 1038 | return 1; |
1039 | break; | |
1040 | ||
1041 | case GE: | |
1042 | case LE: | |
1043 | if (code2 == ORDERED) | |
1044 | return 1; | |
1045 | break; | |
1046 | ||
1047 | case LTGT: | |
1048 | if (code2 == NE || code2 == ORDERED) | |
5924de0b | 1049 | return 1; |
1050 | break; | |
1051 | ||
1052 | case LTU: | |
11088b43 | 1053 | if (code2 == LEU || code2 == NE) |
5924de0b | 1054 | return 1; |
1055 | break; | |
1056 | ||
1057 | case GTU: | |
11088b43 | 1058 | if (code2 == GEU || code2 == NE) |
5924de0b | 1059 | return 1; |
1060 | break; | |
79777bad | 1061 | |
1062 | case UNORDERED: | |
5aa3f5e2 | 1063 | if (code2 == NE || code2 == UNEQ || code2 == UNLE || code2 == UNLT |
1064 | || code2 == UNGE || code2 == UNGT) | |
79777bad | 1065 | return 1; |
1066 | break; | |
7113a566 | 1067 | |
0dbd1c74 | 1068 | default: |
1069 | break; | |
5924de0b | 1070 | } |
1071 | ||
1072 | return 0; | |
1073 | } | |
1074 | \f | |
1075 | /* Return 1 if INSN is an unconditional jump and nothing else. */ | |
1076 | ||
1077 | int | |
1078 | simplejump_p (insn) | |
1079 | rtx insn; | |
1080 | { | |
8d472058 | 1081 | return (GET_CODE (insn) == JUMP_INSN |
1082 | && GET_CODE (PATTERN (insn)) == SET | |
1083 | && GET_CODE (SET_DEST (PATTERN (insn))) == PC | |
1084 | && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF); | |
5924de0b | 1085 | } |
1086 | ||
1087 | /* Return nonzero if INSN is a (possibly) conditional jump | |
7113a566 | 1088 | and nothing more. |
1089 | ||
d670e794 | 1090 | Use this function is deprecated, since we need to support combined |
1091 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
5924de0b | 1092 | |
1093 | int | |
1094 | condjump_p (insn) | |
1095 | rtx insn; | |
1096 | { | |
19cb6b50 | 1097 | rtx x = PATTERN (insn); |
7014838c | 1098 | |
1099 | if (GET_CODE (x) != SET | |
1100 | || GET_CODE (SET_DEST (x)) != PC) | |
4fbe8fa7 | 1101 | return 0; |
7014838c | 1102 | |
1103 | x = SET_SRC (x); | |
1104 | if (GET_CODE (x) == LABEL_REF) | |
4fbe8fa7 | 1105 | return 1; |
7113a566 | 1106 | else |
1107 | return (GET_CODE (x) == IF_THEN_ELSE | |
1108 | && ((GET_CODE (XEXP (x, 2)) == PC | |
1109 | && (GET_CODE (XEXP (x, 1)) == LABEL_REF | |
1110 | || GET_CODE (XEXP (x, 1)) == RETURN)) | |
1111 | || (GET_CODE (XEXP (x, 1)) == PC | |
1112 | && (GET_CODE (XEXP (x, 2)) == LABEL_REF | |
1113 | || GET_CODE (XEXP (x, 2)) == RETURN)))); | |
7014838c | 1114 | |
4fbe8fa7 | 1115 | return 0; |
1116 | } | |
1117 | ||
7014838c | 1118 | /* Return nonzero if INSN is a (possibly) conditional jump inside a |
3a941ad5 | 1119 | PARALLEL. |
7113a566 | 1120 | |
d670e794 | 1121 | Use this function is deprecated, since we need to support combined |
1122 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
4fbe8fa7 | 1123 | |
1124 | int | |
1125 | condjump_in_parallel_p (insn) | |
1126 | rtx insn; | |
1127 | { | |
19cb6b50 | 1128 | rtx x = PATTERN (insn); |
4fbe8fa7 | 1129 | |
1130 | if (GET_CODE (x) != PARALLEL) | |
1131 | return 0; | |
1132 | else | |
1133 | x = XVECEXP (x, 0, 0); | |
1134 | ||
5924de0b | 1135 | if (GET_CODE (x) != SET) |
1136 | return 0; | |
1137 | if (GET_CODE (SET_DEST (x)) != PC) | |
1138 | return 0; | |
1139 | if (GET_CODE (SET_SRC (x)) == LABEL_REF) | |
1140 | return 1; | |
1141 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) | |
1142 | return 0; | |
1143 | if (XEXP (SET_SRC (x), 2) == pc_rtx | |
1144 | && (GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF | |
1145 | || GET_CODE (XEXP (SET_SRC (x), 1)) == RETURN)) | |
1146 | return 1; | |
1147 | if (XEXP (SET_SRC (x), 1) == pc_rtx | |
1148 | && (GET_CODE (XEXP (SET_SRC (x), 2)) == LABEL_REF | |
1149 | || GET_CODE (XEXP (SET_SRC (x), 2)) == RETURN)) | |
1150 | return 1; | |
1151 | return 0; | |
1152 | } | |
1153 | ||
d670e794 | 1154 | /* Return set of PC, otherwise NULL. */ |
1155 | ||
3a941ad5 | 1156 | rtx |
1157 | pc_set (insn) | |
1158 | rtx insn; | |
1159 | { | |
1160 | rtx pat; | |
1161 | if (GET_CODE (insn) != JUMP_INSN) | |
d670e794 | 1162 | return NULL_RTX; |
3a941ad5 | 1163 | pat = PATTERN (insn); |
d670e794 | 1164 | |
1165 | /* The set is allowed to appear either as the insn pattern or | |
1166 | the first set in a PARALLEL. */ | |
1167 | if (GET_CODE (pat) == PARALLEL) | |
1168 | pat = XVECEXP (pat, 0, 0); | |
3a941ad5 | 1169 | if (GET_CODE (pat) == SET && GET_CODE (SET_DEST (pat)) == PC) |
1170 | return pat; | |
d670e794 | 1171 | |
1172 | return NULL_RTX; | |
3a941ad5 | 1173 | } |
1174 | ||
d670e794 | 1175 | /* Return true when insn is an unconditional direct jump, |
1176 | possibly bundled inside a PARALLEL. */ | |
1177 | ||
3a941ad5 | 1178 | int |
1179 | any_uncondjump_p (insn) | |
1180 | rtx insn; | |
1181 | { | |
1182 | rtx x = pc_set (insn); | |
1183 | if (!x) | |
1184 | return 0; | |
1185 | if (GET_CODE (SET_SRC (x)) != LABEL_REF) | |
1186 | return 0; | |
1187 | return 1; | |
1188 | } | |
1189 | ||
d670e794 | 1190 | /* Return true when insn is a conditional jump. This function works for |
3a941ad5 | 1191 | instructions containing PC sets in PARALLELs. The instruction may have |
1192 | various other effects so before removing the jump you must verify | |
9641f63c | 1193 | onlyjump_p. |
3a941ad5 | 1194 | |
d670e794 | 1195 | Note that unlike condjump_p it returns false for unconditional jumps. */ |
1196 | ||
3a941ad5 | 1197 | int |
1198 | any_condjump_p (insn) | |
1199 | rtx insn; | |
1200 | { | |
1201 | rtx x = pc_set (insn); | |
d670e794 | 1202 | enum rtx_code a, b; |
1203 | ||
3a941ad5 | 1204 | if (!x) |
1205 | return 0; | |
d670e794 | 1206 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) |
1207 | return 0; | |
3a941ad5 | 1208 | |
d670e794 | 1209 | a = GET_CODE (XEXP (SET_SRC (x), 1)); |
1210 | b = GET_CODE (XEXP (SET_SRC (x), 2)); | |
3a941ad5 | 1211 | |
d670e794 | 1212 | return ((b == PC && (a == LABEL_REF || a == RETURN)) |
7113a566 | 1213 | || (a == PC && (b == LABEL_REF || b == RETURN))); |
3a941ad5 | 1214 | } |
1215 | ||
8f7b24f3 | 1216 | /* Return the label of a conditional jump. */ |
1217 | ||
1218 | rtx | |
1219 | condjump_label (insn) | |
1220 | rtx insn; | |
1221 | { | |
d670e794 | 1222 | rtx x = pc_set (insn); |
8f7b24f3 | 1223 | |
d670e794 | 1224 | if (!x) |
8f7b24f3 | 1225 | return NULL_RTX; |
1226 | x = SET_SRC (x); | |
1227 | if (GET_CODE (x) == LABEL_REF) | |
1228 | return x; | |
1229 | if (GET_CODE (x) != IF_THEN_ELSE) | |
1230 | return NULL_RTX; | |
1231 | if (XEXP (x, 2) == pc_rtx && GET_CODE (XEXP (x, 1)) == LABEL_REF) | |
1232 | return XEXP (x, 1); | |
1233 | if (XEXP (x, 1) == pc_rtx && GET_CODE (XEXP (x, 2)) == LABEL_REF) | |
1234 | return XEXP (x, 2); | |
1235 | return NULL_RTX; | |
1236 | } | |
1237 | ||
71caadc0 | 1238 | /* Return true if INSN is a (possibly conditional) return insn. */ |
1239 | ||
1240 | static int | |
1241 | returnjump_p_1 (loc, data) | |
1242 | rtx *loc; | |
1243 | void *data ATTRIBUTE_UNUSED; | |
1244 | { | |
1245 | rtx x = *loc; | |
c3987c92 | 1246 | |
1247 | return x && (GET_CODE (x) == RETURN | |
1248 | || (GET_CODE (x) == SET && SET_IS_RETURN_P (x))); | |
71caadc0 | 1249 | } |
1250 | ||
1251 | int | |
1252 | returnjump_p (insn) | |
1253 | rtx insn; | |
1254 | { | |
cbd914e1 | 1255 | if (GET_CODE (insn) != JUMP_INSN) |
1256 | return 0; | |
71caadc0 | 1257 | return for_each_rtx (&PATTERN (insn), returnjump_p_1, NULL); |
1258 | } | |
1259 | ||
459e9193 | 1260 | /* Return true if INSN is a jump that only transfers control and |
1261 | nothing more. */ | |
1262 | ||
1263 | int | |
1264 | onlyjump_p (insn) | |
1265 | rtx insn; | |
1266 | { | |
1267 | rtx set; | |
1268 | ||
1269 | if (GET_CODE (insn) != JUMP_INSN) | |
1270 | return 0; | |
1271 | ||
1272 | set = single_set (insn); | |
1273 | if (set == NULL) | |
1274 | return 0; | |
1275 | if (GET_CODE (SET_DEST (set)) != PC) | |
1276 | return 0; | |
1277 | if (side_effects_p (SET_SRC (set))) | |
1278 | return 0; | |
1279 | ||
1280 | return 1; | |
1281 | } | |
1282 | ||
9bf8c346 | 1283 | #ifdef HAVE_cc0 |
1284 | ||
2dcd83ba | 1285 | /* Return non-zero if X is an RTX that only sets the condition codes |
1286 | and has no side effects. */ | |
1287 | ||
1288 | int | |
1289 | only_sets_cc0_p (x) | |
1290 | rtx x; | |
1291 | { | |
1292 | ||
1293 | if (! x) | |
1294 | return 0; | |
1295 | ||
1296 | if (INSN_P (x)) | |
1297 | x = PATTERN (x); | |
1298 | ||
1299 | return sets_cc0_p (x) == 1 && ! side_effects_p (x); | |
1300 | } | |
1301 | ||
5924de0b | 1302 | /* Return 1 if X is an RTX that does nothing but set the condition codes |
1303 | and CLOBBER or USE registers. | |
1304 | Return -1 if X does explicitly set the condition codes, | |
1305 | but also does other things. */ | |
1306 | ||
1307 | int | |
1308 | sets_cc0_p (x) | |
2dcd83ba | 1309 | rtx x; |
5924de0b | 1310 | { |
2dcd83ba | 1311 | |
1312 | if (! x) | |
1313 | return 0; | |
1314 | ||
1315 | if (INSN_P (x)) | |
1316 | x = PATTERN (x); | |
1317 | ||
5924de0b | 1318 | if (GET_CODE (x) == SET && SET_DEST (x) == cc0_rtx) |
1319 | return 1; | |
1320 | if (GET_CODE (x) == PARALLEL) | |
1321 | { | |
1322 | int i; | |
1323 | int sets_cc0 = 0; | |
1324 | int other_things = 0; | |
1325 | for (i = XVECLEN (x, 0) - 1; i >= 0; i--) | |
1326 | { | |
1327 | if (GET_CODE (XVECEXP (x, 0, i)) == SET | |
1328 | && SET_DEST (XVECEXP (x, 0, i)) == cc0_rtx) | |
1329 | sets_cc0 = 1; | |
1330 | else if (GET_CODE (XVECEXP (x, 0, i)) == SET) | |
1331 | other_things = 1; | |
1332 | } | |
1333 | return ! sets_cc0 ? 0 : other_things ? -1 : 1; | |
1334 | } | |
1335 | return 0; | |
5924de0b | 1336 | } |
9bf8c346 | 1337 | #endif |
5924de0b | 1338 | \f |
1339 | /* Follow any unconditional jump at LABEL; | |
1340 | return the ultimate label reached by any such chain of jumps. | |
1341 | If LABEL is not followed by a jump, return LABEL. | |
35e0b416 | 1342 | If the chain loops or we can't find end, return LABEL, |
1343 | since that tells caller to avoid changing the insn. | |
5924de0b | 1344 | |
1345 | If RELOAD_COMPLETED is 0, we do not chain across a NOTE_INSN_LOOP_BEG or | |
1346 | a USE or CLOBBER. */ | |
1347 | ||
1348 | rtx | |
1349 | follow_jumps (label) | |
1350 | rtx label; | |
1351 | { | |
19cb6b50 | 1352 | rtx insn; |
1353 | rtx next; | |
1354 | rtx value = label; | |
1355 | int depth; | |
5924de0b | 1356 | |
1357 | for (depth = 0; | |
1358 | (depth < 10 | |
1359 | && (insn = next_active_insn (value)) != 0 | |
1360 | && GET_CODE (insn) == JUMP_INSN | |
ba08b7e7 | 1361 | && ((JUMP_LABEL (insn) != 0 && any_uncondjump_p (insn) |
1362 | && onlyjump_p (insn)) | |
f93ed41b | 1363 | || GET_CODE (PATTERN (insn)) == RETURN) |
5924de0b | 1364 | && (next = NEXT_INSN (insn)) |
1365 | && GET_CODE (next) == BARRIER); | |
1366 | depth++) | |
1367 | { | |
1368 | /* Don't chain through the insn that jumps into a loop | |
1369 | from outside the loop, | |
1370 | since that would create multiple loop entry jumps | |
1371 | and prevent loop optimization. */ | |
1372 | rtx tem; | |
1373 | if (!reload_completed) | |
1374 | for (tem = value; tem != insn; tem = NEXT_INSN (tem)) | |
1375 | if (GET_CODE (tem) == NOTE | |
55b8f81a | 1376 | && (NOTE_LINE_NUMBER (tem) == NOTE_INSN_LOOP_BEG |
1377 | /* ??? Optional. Disables some optimizations, but makes | |
1378 | gcov output more accurate with -O. */ | |
1379 | || (flag_test_coverage && NOTE_LINE_NUMBER (tem) > 0))) | |
5924de0b | 1380 | return value; |
1381 | ||
1382 | /* If we have found a cycle, make the insn jump to itself. */ | |
1383 | if (JUMP_LABEL (insn) == label) | |
35e0b416 | 1384 | return label; |
cf03b15b | 1385 | |
1386 | tem = next_active_insn (JUMP_LABEL (insn)); | |
1387 | if (tem && (GET_CODE (PATTERN (tem)) == ADDR_VEC | |
1388 | || GET_CODE (PATTERN (tem)) == ADDR_DIFF_VEC)) | |
1389 | break; | |
1390 | ||
5924de0b | 1391 | value = JUMP_LABEL (insn); |
1392 | } | |
35e0b416 | 1393 | if (depth == 10) |
1394 | return label; | |
5924de0b | 1395 | return value; |
1396 | } | |
1397 | ||
5924de0b | 1398 | \f |
1399 | /* Find all CODE_LABELs referred to in X, and increment their use counts. | |
1400 | If INSN is a JUMP_INSN and there is at least one CODE_LABEL referenced | |
1401 | in INSN, then store one of them in JUMP_LABEL (INSN). | |
1402 | If INSN is an INSN or a CALL_INSN and there is at least one CODE_LABEL | |
1403 | referenced in INSN, add a REG_LABEL note containing that label to INSN. | |
1404 | Also, when there are consecutive labels, canonicalize on the last of them. | |
1405 | ||
1406 | Note that two labels separated by a loop-beginning note | |
1407 | must be kept distinct if we have not yet done loop-optimization, | |
1408 | because the gap between them is where loop-optimize | |
1409 | will want to move invariant code to. CROSS_JUMP tells us | |
bf73fcf4 | 1410 | that loop-optimization is done with. */ |
5924de0b | 1411 | |
5377f687 | 1412 | void |
bf73fcf4 | 1413 | mark_jump_label (x, insn, in_mem) |
19cb6b50 | 1414 | rtx x; |
5924de0b | 1415 | rtx insn; |
190099a6 | 1416 | int in_mem; |
5924de0b | 1417 | { |
19cb6b50 | 1418 | RTX_CODE code = GET_CODE (x); |
1419 | int i; | |
1420 | const char *fmt; | |
5924de0b | 1421 | |
1422 | switch (code) | |
1423 | { | |
1424 | case PC: | |
1425 | case CC0: | |
1426 | case REG: | |
1427 | case SUBREG: | |
1428 | case CONST_INT: | |
5924de0b | 1429 | case CONST_DOUBLE: |
1430 | case CLOBBER: | |
1431 | case CALL: | |
1432 | return; | |
1433 | ||
d8e0d332 | 1434 | case MEM: |
190099a6 | 1435 | in_mem = 1; |
1436 | break; | |
1437 | ||
1438 | case SYMBOL_REF: | |
1439 | if (!in_mem) | |
7113a566 | 1440 | return; |
190099a6 | 1441 | |
d8e0d332 | 1442 | /* If this is a constant-pool reference, see if it is a label. */ |
190099a6 | 1443 | if (CONSTANT_POOL_ADDRESS_P (x)) |
bf73fcf4 | 1444 | mark_jump_label (get_pool_constant (x), insn, in_mem); |
d8e0d332 | 1445 | break; |
1446 | ||
5924de0b | 1447 | case LABEL_REF: |
1448 | { | |
b4d3bcce | 1449 | rtx label = XEXP (x, 0); |
b4d3bcce | 1450 | |
74b0991d | 1451 | /* Ignore remaining references to unreachable labels that |
1452 | have been deleted. */ | |
7113a566 | 1453 | if (GET_CODE (label) == NOTE |
74b0991d | 1454 | && NOTE_LINE_NUMBER (label) == NOTE_INSN_DELETED_LABEL) |
1455 | break; | |
1456 | ||
5924de0b | 1457 | if (GET_CODE (label) != CODE_LABEL) |
1458 | abort (); | |
b4d3bcce | 1459 | |
f08cae9d | 1460 | /* Ignore references to labels of containing functions. */ |
1461 | if (LABEL_REF_NONLOCAL_P (x)) | |
1462 | break; | |
b4d3bcce | 1463 | |
5924de0b | 1464 | XEXP (x, 0) = label; |
943e16d8 | 1465 | if (! insn || ! INSN_DELETED_P (insn)) |
1466 | ++LABEL_NUSES (label); | |
b4d3bcce | 1467 | |
5924de0b | 1468 | if (insn) |
1469 | { | |
1470 | if (GET_CODE (insn) == JUMP_INSN) | |
1471 | JUMP_LABEL (insn) = label; | |
ab2237b5 | 1472 | else |
e89849bd | 1473 | { |
ab2237b5 | 1474 | /* Add a REG_LABEL note for LABEL unless there already |
1475 | is one. All uses of a label, except for labels | |
1476 | that are the targets of jumps, must have a | |
1477 | REG_LABEL note. */ | |
1478 | if (! find_reg_note (insn, REG_LABEL, label)) | |
60d9e0ee | 1479 | REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, label, |
ab2237b5 | 1480 | REG_NOTES (insn)); |
5924de0b | 1481 | } |
1482 | } | |
1483 | return; | |
1484 | } | |
1485 | ||
1486 | /* Do walk the labels in a vector, but not the first operand of an | |
1487 | ADDR_DIFF_VEC. Don't set the JUMP_LABEL of a vector. */ | |
1488 | case ADDR_VEC: | |
1489 | case ADDR_DIFF_VEC: | |
943e16d8 | 1490 | if (! INSN_DELETED_P (insn)) |
1491 | { | |
1492 | int eltnum = code == ADDR_DIFF_VEC ? 1 : 0; | |
5924de0b | 1493 | |
943e16d8 | 1494 | for (i = 0; i < XVECLEN (x, eltnum); i++) |
bf73fcf4 | 1495 | mark_jump_label (XVECEXP (x, eltnum, i), NULL_RTX, in_mem); |
943e16d8 | 1496 | } |
0dbd1c74 | 1497 | return; |
7113a566 | 1498 | |
0dbd1c74 | 1499 | default: |
1500 | break; | |
5924de0b | 1501 | } |
1502 | ||
1503 | fmt = GET_RTX_FORMAT (code); | |
1504 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1505 | { | |
1506 | if (fmt[i] == 'e') | |
bf73fcf4 | 1507 | mark_jump_label (XEXP (x, i), insn, in_mem); |
5924de0b | 1508 | else if (fmt[i] == 'E') |
1509 | { | |
19cb6b50 | 1510 | int j; |
5924de0b | 1511 | for (j = 0; j < XVECLEN (x, i); j++) |
bf73fcf4 | 1512 | mark_jump_label (XVECEXP (x, i, j), insn, in_mem); |
5924de0b | 1513 | } |
1514 | } | |
1515 | } | |
1516 | ||
1517 | /* If all INSN does is set the pc, delete it, | |
1518 | and delete the insn that set the condition codes for it | |
1519 | if that's what the previous thing was. */ | |
1520 | ||
1521 | void | |
1522 | delete_jump (insn) | |
1523 | rtx insn; | |
1524 | { | |
19cb6b50 | 1525 | rtx set = single_set (insn); |
f4ef05ab | 1526 | |
1527 | if (set && GET_CODE (SET_DEST (set)) == PC) | |
1528 | delete_computation (insn); | |
1529 | } | |
1530 | ||
155b05dc | 1531 | /* Verify INSN is a BARRIER and delete it. */ |
1532 | ||
1533 | void | |
1534 | delete_barrier (insn) | |
1535 | rtx insn; | |
1536 | { | |
1537 | if (GET_CODE (insn) != BARRIER) | |
1538 | abort (); | |
1539 | ||
1540 | delete_insn (insn); | |
1541 | } | |
1542 | ||
ab1241f2 | 1543 | /* Recursively delete prior insns that compute the value (used only by INSN |
1544 | which the caller is deleting) stored in the register mentioned by NOTE | |
1545 | which is a REG_DEAD note associated with INSN. */ | |
1546 | ||
1547 | static void | |
1548 | delete_prior_computation (note, insn) | |
1549 | rtx note; | |
1550 | rtx insn; | |
1551 | { | |
1552 | rtx our_prev; | |
1553 | rtx reg = XEXP (note, 0); | |
1554 | ||
1555 | for (our_prev = prev_nonnote_insn (insn); | |
272a2170 | 1556 | our_prev && (GET_CODE (our_prev) == INSN |
1557 | || GET_CODE (our_prev) == CALL_INSN); | |
ab1241f2 | 1558 | our_prev = prev_nonnote_insn (our_prev)) |
1559 | { | |
1560 | rtx pat = PATTERN (our_prev); | |
1561 | ||
272a2170 | 1562 | /* If we reach a CALL which is not calling a const function |
1563 | or the callee pops the arguments, then give up. */ | |
1564 | if (GET_CODE (our_prev) == CALL_INSN | |
06a652d1 | 1565 | && (! CONST_OR_PURE_CALL_P (our_prev) |
272a2170 | 1566 | || GET_CODE (pat) != SET || GET_CODE (SET_SRC (pat)) != CALL)) |
1567 | break; | |
1568 | ||
ab1241f2 | 1569 | /* If we reach a SEQUENCE, it is too complex to try to |
1570 | do anything with it, so give up. */ | |
1571 | if (GET_CODE (pat) == SEQUENCE) | |
1572 | break; | |
1573 | ||
1574 | if (GET_CODE (pat) == USE | |
1575 | && GET_CODE (XEXP (pat, 0)) == INSN) | |
1576 | /* reorg creates USEs that look like this. We leave them | |
1577 | alone because reorg needs them for its own purposes. */ | |
1578 | break; | |
1579 | ||
1580 | if (reg_set_p (reg, pat)) | |
1581 | { | |
272a2170 | 1582 | if (side_effects_p (pat) && GET_CODE (our_prev) != CALL_INSN) |
ab1241f2 | 1583 | break; |
1584 | ||
1585 | if (GET_CODE (pat) == PARALLEL) | |
1586 | { | |
1587 | /* If we find a SET of something else, we can't | |
1588 | delete the insn. */ | |
1589 | ||
1590 | int i; | |
1591 | ||
1592 | for (i = 0; i < XVECLEN (pat, 0); i++) | |
1593 | { | |
1594 | rtx part = XVECEXP (pat, 0, i); | |
1595 | ||
1596 | if (GET_CODE (part) == SET | |
1597 | && SET_DEST (part) != reg) | |
1598 | break; | |
1599 | } | |
1600 | ||
1601 | if (i == XVECLEN (pat, 0)) | |
1602 | delete_computation (our_prev); | |
1603 | } | |
1604 | else if (GET_CODE (pat) == SET | |
1605 | && GET_CODE (SET_DEST (pat)) == REG) | |
1606 | { | |
1607 | int dest_regno = REGNO (SET_DEST (pat)); | |
1608 | int dest_endregno | |
7113a566 | 1609 | = (dest_regno |
1610 | + (dest_regno < FIRST_PSEUDO_REGISTER | |
ab1241f2 | 1611 | ? HARD_REGNO_NREGS (dest_regno, |
7113a566 | 1612 | GET_MODE (SET_DEST (pat))) : 1)); |
ab1241f2 | 1613 | int regno = REGNO (reg); |
7113a566 | 1614 | int endregno |
1615 | = (regno | |
1616 | + (regno < FIRST_PSEUDO_REGISTER | |
1617 | ? HARD_REGNO_NREGS (regno, GET_MODE (reg)) : 1)); | |
ab1241f2 | 1618 | |
1619 | if (dest_regno >= regno | |
1620 | && dest_endregno <= endregno) | |
1621 | delete_computation (our_prev); | |
1622 | ||
1623 | /* We may have a multi-word hard register and some, but not | |
1624 | all, of the words of the register are needed in subsequent | |
1625 | insns. Write REG_UNUSED notes for those parts that were not | |
1626 | needed. */ | |
1627 | else if (dest_regno <= regno | |
272a2170 | 1628 | && dest_endregno >= endregno) |
ab1241f2 | 1629 | { |
1630 | int i; | |
1631 | ||
1632 | REG_NOTES (our_prev) | |
7113a566 | 1633 | = gen_rtx_EXPR_LIST (REG_UNUSED, reg, |
1634 | REG_NOTES (our_prev)); | |
ab1241f2 | 1635 | |
1636 | for (i = dest_regno; i < dest_endregno; i++) | |
1637 | if (! find_regno_note (our_prev, REG_UNUSED, i)) | |
1638 | break; | |
1639 | ||
1640 | if (i == dest_endregno) | |
1641 | delete_computation (our_prev); | |
1642 | } | |
1643 | } | |
1644 | ||
1645 | break; | |
1646 | } | |
1647 | ||
1648 | /* If PAT references the register that dies here, it is an | |
1649 | additional use. Hence any prior SET isn't dead. However, this | |
1650 | insn becomes the new place for the REG_DEAD note. */ | |
1651 | if (reg_overlap_mentioned_p (reg, pat)) | |
1652 | { | |
1653 | XEXP (note, 1) = REG_NOTES (our_prev); | |
1654 | REG_NOTES (our_prev) = note; | |
1655 | break; | |
1656 | } | |
1657 | } | |
1658 | } | |
1659 | ||
f4ef05ab | 1660 | /* Delete INSN and recursively delete insns that compute values used only |
1661 | by INSN. This uses the REG_DEAD notes computed during flow analysis. | |
1662 | If we are running before flow.c, we need do nothing since flow.c will | |
1663 | delete dead code. We also can't know if the registers being used are | |
1664 | dead or not at this point. | |
1665 | ||
1666 | Otherwise, look at all our REG_DEAD notes. If a previous insn does | |
1667 | nothing other than set a register that dies in this insn, we can delete | |
1668 | that insn as well. | |
1669 | ||
1670 | On machines with CC0, if CC0 is used in this insn, we may be able to | |
1671 | delete the insn that set it. */ | |
1672 | ||
fb374064 | 1673 | static void |
f4ef05ab | 1674 | delete_computation (insn) |
1675 | rtx insn; | |
1676 | { | |
1677 | rtx note, next; | |
5924de0b | 1678 | |
5924de0b | 1679 | #ifdef HAVE_cc0 |
41d75671 | 1680 | if (reg_referenced_p (cc0_rtx, PATTERN (insn))) |
f4ef05ab | 1681 | { |
5b39732e | 1682 | rtx prev = prev_nonnote_insn (insn); |
5924de0b | 1683 | /* We assume that at this stage |
1684 | CC's are always set explicitly | |
1685 | and always immediately before the jump that | |
1686 | will use them. So if the previous insn | |
1687 | exists to set the CC's, delete it | |
1688 | (unless it performs auto-increments, etc.). */ | |
1689 | if (prev && GET_CODE (prev) == INSN | |
1690 | && sets_cc0_p (PATTERN (prev))) | |
1691 | { | |
1692 | if (sets_cc0_p (PATTERN (prev)) > 0 | |
ab1241f2 | 1693 | && ! side_effects_p (PATTERN (prev))) |
f4ef05ab | 1694 | delete_computation (prev); |
5924de0b | 1695 | else |
1696 | /* Otherwise, show that cc0 won't be used. */ | |
941522d6 | 1697 | REG_NOTES (prev) = gen_rtx_EXPR_LIST (REG_UNUSED, |
1698 | cc0_rtx, REG_NOTES (prev)); | |
5924de0b | 1699 | } |
5b39732e | 1700 | } |
f4ef05ab | 1701 | #endif |
5924de0b | 1702 | |
5b39732e | 1703 | for (note = REG_NOTES (insn); note; note = next) |
1704 | { | |
5b39732e | 1705 | next = XEXP (note, 1); |
5924de0b | 1706 | |
5b39732e | 1707 | if (REG_NOTE_KIND (note) != REG_DEAD |
1708 | /* Verify that the REG_NOTE is legitimate. */ | |
1709 | || GET_CODE (XEXP (note, 0)) != REG) | |
1710 | continue; | |
5924de0b | 1711 | |
ab1241f2 | 1712 | delete_prior_computation (note, insn); |
5924de0b | 1713 | } |
f4ef05ab | 1714 | |
e4bf866d | 1715 | delete_related_insns (insn); |
5924de0b | 1716 | } |
1717 | \f | |
e4bf866d | 1718 | /* Delete insn INSN from the chain of insns and update label ref counts |
1719 | and delete insns now unreachable. | |
1720 | ||
1721 | Returns the first insn after INSN that was not deleted. | |
5924de0b | 1722 | |
e4bf866d | 1723 | Usage of this instruction is deprecated. Use delete_insn instead and |
1724 | subsequent cfg_cleanup pass to delete unreachable code if needed. */ | |
5924de0b | 1725 | |
1726 | rtx | |
e4bf866d | 1727 | delete_related_insns (insn) |
19cb6b50 | 1728 | rtx insn; |
5924de0b | 1729 | { |
19cb6b50 | 1730 | int was_code_label = (GET_CODE (insn) == CODE_LABEL); |
d3df77e9 | 1731 | rtx note; |
e4bf866d | 1732 | rtx next = NEXT_INSN (insn), prev = PREV_INSN (insn); |
5924de0b | 1733 | |
1734 | while (next && INSN_DELETED_P (next)) | |
1735 | next = NEXT_INSN (next); | |
1736 | ||
1737 | /* This insn is already deleted => return first following nondeleted. */ | |
1738 | if (INSN_DELETED_P (insn)) | |
1739 | return next; | |
1740 | ||
e4bf866d | 1741 | delete_insn (insn); |
5924de0b | 1742 | |
5924de0b | 1743 | /* If instruction is followed by a barrier, |
1744 | delete the barrier too. */ | |
1745 | ||
1746 | if (next != 0 && GET_CODE (next) == BARRIER) | |
e4bf866d | 1747 | delete_insn (next); |
5924de0b | 1748 | |
1749 | /* If deleting a jump, decrement the count of the label, | |
1750 | and delete the label if it is now unused. */ | |
1751 | ||
1752 | if (GET_CODE (insn) == JUMP_INSN && JUMP_LABEL (insn)) | |
1793cd6b | 1753 | { |
1754 | rtx lab = JUMP_LABEL (insn), lab_next; | |
1755 | ||
e4bf866d | 1756 | if (LABEL_NUSES (lab) == 0) |
1793cd6b | 1757 | { |
1758 | /* This can delete NEXT or PREV, | |
1759 | either directly if NEXT is JUMP_LABEL (INSN), | |
1760 | or indirectly through more levels of jumps. */ | |
e4bf866d | 1761 | delete_related_insns (lab); |
1793cd6b | 1762 | |
1763 | /* I feel a little doubtful about this loop, | |
1764 | but I see no clean and sure alternative way | |
1765 | to find the first insn after INSN that is not now deleted. | |
1766 | I hope this works. */ | |
1767 | while (next && INSN_DELETED_P (next)) | |
1768 | next = NEXT_INSN (next); | |
1769 | return next; | |
1770 | } | |
1771 | else if ((lab_next = next_nonnote_insn (lab)) != NULL | |
1772 | && GET_CODE (lab_next) == JUMP_INSN | |
1773 | && (GET_CODE (PATTERN (lab_next)) == ADDR_VEC | |
1774 | || GET_CODE (PATTERN (lab_next)) == ADDR_DIFF_VEC)) | |
1775 | { | |
1776 | /* If we're deleting the tablejump, delete the dispatch table. | |
4a82352a | 1777 | We may not be able to kill the label immediately preceding |
1793cd6b | 1778 | just yet, as it might be referenced in code leading up to |
1779 | the tablejump. */ | |
e4bf866d | 1780 | delete_related_insns (lab_next); |
1793cd6b | 1781 | } |
1782 | } | |
5924de0b | 1783 | |
9c9e0c01 | 1784 | /* Likewise if we're deleting a dispatch table. */ |
1785 | ||
1786 | if (GET_CODE (insn) == JUMP_INSN | |
1787 | && (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
1788 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)) | |
1789 | { | |
1790 | rtx pat = PATTERN (insn); | |
1791 | int i, diff_vec_p = GET_CODE (pat) == ADDR_DIFF_VEC; | |
1792 | int len = XVECLEN (pat, diff_vec_p); | |
1793 | ||
1794 | for (i = 0; i < len; i++) | |
e4bf866d | 1795 | if (LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0)) == 0) |
1796 | delete_related_insns (XEXP (XVECEXP (pat, diff_vec_p, i), 0)); | |
9c9e0c01 | 1797 | while (next && INSN_DELETED_P (next)) |
1798 | next = NEXT_INSN (next); | |
1799 | return next; | |
1800 | } | |
1801 | ||
d3df77e9 | 1802 | /* Likewise for an ordinary INSN / CALL_INSN with a REG_LABEL note. */ |
1803 | if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
1804 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) | |
0c97f529 | 1805 | if (REG_NOTE_KIND (note) == REG_LABEL |
1806 | /* This could also be a NOTE_INSN_DELETED_LABEL note. */ | |
1807 | && GET_CODE (XEXP (note, 0)) == CODE_LABEL) | |
e4bf866d | 1808 | if (LABEL_NUSES (XEXP (note, 0)) == 0) |
1809 | delete_related_insns (XEXP (note, 0)); | |
d3df77e9 | 1810 | |
5924de0b | 1811 | while (prev && (INSN_DELETED_P (prev) || GET_CODE (prev) == NOTE)) |
1812 | prev = PREV_INSN (prev); | |
1813 | ||
1814 | /* If INSN was a label and a dispatch table follows it, | |
1815 | delete the dispatch table. The tablejump must have gone already. | |
1816 | It isn't useful to fall through into a table. */ | |
1817 | ||
9cdc08c6 | 1818 | if (was_code_label |
5924de0b | 1819 | && NEXT_INSN (insn) != 0 |
1820 | && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN | |
1821 | && (GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_VEC | |
1822 | || GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_DIFF_VEC)) | |
e4bf866d | 1823 | next = delete_related_insns (NEXT_INSN (insn)); |
5924de0b | 1824 | |
1825 | /* If INSN was a label, delete insns following it if now unreachable. */ | |
1826 | ||
9cdc08c6 | 1827 | if (was_code_label && prev && GET_CODE (prev) == BARRIER) |
5924de0b | 1828 | { |
19cb6b50 | 1829 | RTX_CODE code; |
5924de0b | 1830 | while (next != 0 |
fb374064 | 1831 | && (GET_RTX_CLASS (code = GET_CODE (next)) == 'i' |
64f0b11f | 1832 | || code == NOTE || code == BARRIER |
59bee35e | 1833 | || (code == CODE_LABEL && INSN_DELETED_P (next)))) |
5924de0b | 1834 | { |
1835 | if (code == NOTE | |
1836 | && NOTE_LINE_NUMBER (next) != NOTE_INSN_FUNCTION_END) | |
1837 | next = NEXT_INSN (next); | |
59bee35e | 1838 | /* Keep going past other deleted labels to delete what follows. */ |
1839 | else if (code == CODE_LABEL && INSN_DELETED_P (next)) | |
1840 | next = NEXT_INSN (next); | |
5924de0b | 1841 | else |
1842 | /* Note: if this deletes a jump, it can cause more | |
1843 | deletion of unreachable code, after a different label. | |
1844 | As long as the value from this recursive call is correct, | |
1845 | this invocation functions correctly. */ | |
e4bf866d | 1846 | next = delete_related_insns (next); |
5924de0b | 1847 | } |
1848 | } | |
1849 | ||
1850 | return next; | |
1851 | } | |
1852 | ||
1853 | /* Advance from INSN till reaching something not deleted | |
1854 | then return that. May return INSN itself. */ | |
1855 | ||
1856 | rtx | |
1857 | next_nondeleted_insn (insn) | |
1858 | rtx insn; | |
1859 | { | |
1860 | while (INSN_DELETED_P (insn)) | |
1861 | insn = NEXT_INSN (insn); | |
1862 | return insn; | |
1863 | } | |
1864 | \f | |
1865 | /* Delete a range of insns from FROM to TO, inclusive. | |
1866 | This is for the sake of peephole optimization, so assume | |
1867 | that whatever these insns do will still be done by a new | |
1868 | peephole insn that will replace them. */ | |
1869 | ||
1870 | void | |
1871 | delete_for_peephole (from, to) | |
19cb6b50 | 1872 | rtx from, to; |
5924de0b | 1873 | { |
19cb6b50 | 1874 | rtx insn = from; |
5924de0b | 1875 | |
1876 | while (1) | |
1877 | { | |
19cb6b50 | 1878 | rtx next = NEXT_INSN (insn); |
1879 | rtx prev = PREV_INSN (insn); | |
5924de0b | 1880 | |
1881 | if (GET_CODE (insn) != NOTE) | |
1882 | { | |
1883 | INSN_DELETED_P (insn) = 1; | |
1884 | ||
1885 | /* Patch this insn out of the chain. */ | |
1886 | /* We don't do this all at once, because we | |
1887 | must preserve all NOTEs. */ | |
1888 | if (prev) | |
1889 | NEXT_INSN (prev) = next; | |
1890 | ||
1891 | if (next) | |
1892 | PREV_INSN (next) = prev; | |
1893 | } | |
1894 | ||
1895 | if (insn == to) | |
1896 | break; | |
1897 | insn = next; | |
1898 | } | |
1899 | ||
1900 | /* Note that if TO is an unconditional jump | |
1901 | we *do not* delete the BARRIER that follows, | |
1902 | since the peephole that replaces this sequence | |
1903 | is also an unconditional jump in that case. */ | |
1904 | } | |
1905 | \f | |
71a3455a | 1906 | /* We have determined that INSN is never reached, and are about to |
1907 | delete it. Print a warning if the user asked for one. | |
1908 | ||
1909 | To try to make this warning more useful, this should only be called | |
1910 | once per basic block not reached, and it only warns when the basic | |
1911 | block contains more than one line from the current function, and | |
1912 | contains at least one operation. CSE and inlining can duplicate insns, | |
1913 | so it's possible to get spurious warnings from this. */ | |
1914 | ||
1915 | void | |
5b154f04 | 1916 | never_reached_warning (avoided_insn, finish) |
1917 | rtx avoided_insn, finish; | |
71a3455a | 1918 | { |
1919 | rtx insn; | |
1920 | rtx a_line_note = NULL; | |
5b154f04 | 1921 | int two_avoided_lines = 0, contains_insn = 0, reached_end = 0; |
7113a566 | 1922 | |
71a3455a | 1923 | if (! warn_notreached) |
1924 | return; | |
1925 | ||
1926 | /* Scan forwards, looking at LINE_NUMBER notes, until | |
1927 | we hit a LABEL or we run out of insns. */ | |
7113a566 | 1928 | |
71a3455a | 1929 | for (insn = avoided_insn; insn != NULL; insn = NEXT_INSN (insn)) |
1930 | { | |
5b154f04 | 1931 | if (finish == NULL && GET_CODE (insn) == CODE_LABEL) |
7113a566 | 1932 | break; |
5b154f04 | 1933 | |
1934 | if (GET_CODE (insn) == NOTE /* A line number note? */ | |
1935 | && NOTE_LINE_NUMBER (insn) >= 0) | |
71a3455a | 1936 | { |
1937 | if (a_line_note == NULL) | |
1938 | a_line_note = insn; | |
1939 | else | |
1940 | two_avoided_lines |= (NOTE_LINE_NUMBER (a_line_note) | |
1941 | != NOTE_LINE_NUMBER (insn)); | |
1942 | } | |
9204e736 | 1943 | else if (INSN_P (insn)) |
5b154f04 | 1944 | { |
1945 | if (reached_end) | |
1946 | break; | |
1947 | contains_insn = 1; | |
1948 | } | |
1949 | ||
1950 | if (insn == finish) | |
1951 | reached_end = 1; | |
71a3455a | 1952 | } |
1953 | if (two_avoided_lines && contains_insn) | |
1954 | warning_with_file_and_line (NOTE_SOURCE_FILE (a_line_note), | |
1955 | NOTE_LINE_NUMBER (a_line_note), | |
1956 | "will never be executed"); | |
1957 | } | |
1958 | \f | |
a8b5d014 | 1959 | /* Throughout LOC, redirect OLABEL to NLABEL. Treat null OLABEL or |
1960 | NLABEL as a return. Accrue modifications into the change group. */ | |
5924de0b | 1961 | |
a8b5d014 | 1962 | static void |
1963 | redirect_exp_1 (loc, olabel, nlabel, insn) | |
1964 | rtx *loc; | |
1965 | rtx olabel, nlabel; | |
5924de0b | 1966 | rtx insn; |
1967 | { | |
19cb6b50 | 1968 | rtx x = *loc; |
1969 | RTX_CODE code = GET_CODE (x); | |
1970 | int i; | |
1971 | const char *fmt; | |
5924de0b | 1972 | |
a8b5d014 | 1973 | if (code == LABEL_REF) |
5924de0b | 1974 | { |
a8b5d014 | 1975 | if (XEXP (x, 0) == olabel) |
1976 | { | |
1977 | rtx n; | |
1978 | if (nlabel) | |
1979 | n = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1980 | else | |
7113a566 | 1981 | n = gen_rtx_RETURN (VOIDmode); |
5924de0b | 1982 | |
a8b5d014 | 1983 | validate_change (insn, loc, n, 1); |
1984 | return; | |
1985 | } | |
1986 | } | |
1987 | else if (code == RETURN && olabel == 0) | |
1988 | { | |
1989 | x = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1990 | if (loc == &PATTERN (insn)) | |
1991 | x = gen_rtx_SET (VOIDmode, pc_rtx, x); | |
1992 | validate_change (insn, loc, x, 1); | |
1993 | return; | |
1994 | } | |
5924de0b | 1995 | |
a8b5d014 | 1996 | if (code == SET && nlabel == 0 && SET_DEST (x) == pc_rtx |
1997 | && GET_CODE (SET_SRC (x)) == LABEL_REF | |
1998 | && XEXP (SET_SRC (x), 0) == olabel) | |
1999 | { | |
2000 | validate_change (insn, loc, gen_rtx_RETURN (VOIDmode), 1); | |
2001 | return; | |
5924de0b | 2002 | } |
2003 | ||
2004 | fmt = GET_RTX_FORMAT (code); | |
2005 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
2006 | { | |
2007 | if (fmt[i] == 'e') | |
a8b5d014 | 2008 | redirect_exp_1 (&XEXP (x, i), olabel, nlabel, insn); |
1bd8ca86 | 2009 | else if (fmt[i] == 'E') |
5924de0b | 2010 | { |
19cb6b50 | 2011 | int j; |
5924de0b | 2012 | for (j = 0; j < XVECLEN (x, i); j++) |
a8b5d014 | 2013 | redirect_exp_1 (&XVECEXP (x, i, j), olabel, nlabel, insn); |
5924de0b | 2014 | } |
2015 | } | |
a8b5d014 | 2016 | } |
5924de0b | 2017 | |
a8b5d014 | 2018 | /* Similar, but apply the change group and report success or failure. */ |
2019 | ||
ba08b7e7 | 2020 | static int |
2021 | redirect_exp (olabel, nlabel, insn) | |
a8b5d014 | 2022 | rtx olabel, nlabel; |
2023 | rtx insn; | |
2024 | { | |
ba08b7e7 | 2025 | rtx *loc; |
2026 | ||
2027 | if (GET_CODE (PATTERN (insn)) == PARALLEL) | |
2028 | loc = &XVECEXP (PATTERN (insn), 0, 0); | |
2029 | else | |
2030 | loc = &PATTERN (insn); | |
2031 | ||
a8b5d014 | 2032 | redirect_exp_1 (loc, olabel, nlabel, insn); |
2033 | if (num_validated_changes () == 0) | |
2034 | return 0; | |
2035 | ||
2036 | return apply_change_group (); | |
5924de0b | 2037 | } |
a8b5d014 | 2038 | |
2039 | /* Make JUMP go to NLABEL instead of where it jumps now. Accrue | |
2040 | the modifications into the change group. Return false if we did | |
2041 | not see how to do that. */ | |
2042 | ||
2043 | int | |
2044 | redirect_jump_1 (jump, nlabel) | |
2045 | rtx jump, nlabel; | |
2046 | { | |
2047 | int ochanges = num_validated_changes (); | |
ba08b7e7 | 2048 | rtx *loc; |
2049 | ||
2050 | if (GET_CODE (PATTERN (jump)) == PARALLEL) | |
2051 | loc = &XVECEXP (PATTERN (jump), 0, 0); | |
2052 | else | |
2053 | loc = &PATTERN (jump); | |
2054 | ||
2055 | redirect_exp_1 (loc, JUMP_LABEL (jump), nlabel, jump); | |
a8b5d014 | 2056 | return num_validated_changes () > ochanges; |
2057 | } | |
2058 | ||
2059 | /* Make JUMP go to NLABEL instead of where it jumps now. If the old | |
2060 | jump target label is unused as a result, it and the code following | |
2061 | it may be deleted. | |
5924de0b | 2062 | |
2063 | If NLABEL is zero, we are to turn the jump into a (possibly conditional) | |
2064 | RETURN insn. | |
2065 | ||
a8b5d014 | 2066 | The return value will be 1 if the change was made, 0 if it wasn't |
2067 | (this can only occur for NLABEL == 0). */ | |
5924de0b | 2068 | |
2069 | int | |
f8cacb57 | 2070 | redirect_jump (jump, nlabel, delete_unused) |
5924de0b | 2071 | rtx jump, nlabel; |
f8cacb57 | 2072 | int delete_unused; |
5924de0b | 2073 | { |
19cb6b50 | 2074 | rtx olabel = JUMP_LABEL (jump); |
5924de0b | 2075 | |
2076 | if (nlabel == olabel) | |
2077 | return 1; | |
2078 | ||
ba08b7e7 | 2079 | if (! redirect_exp (olabel, nlabel, jump)) |
5924de0b | 2080 | return 0; |
2081 | ||
5924de0b | 2082 | JUMP_LABEL (jump) = nlabel; |
2083 | if (nlabel) | |
2084 | ++LABEL_NUSES (nlabel); | |
2085 | ||
9cf49039 | 2086 | /* If we're eliding the jump over exception cleanups at the end of a |
2087 | function, move the function end note so that -Wreturn-type works. */ | |
4476207f | 2088 | if (olabel && nlabel |
2089 | && NEXT_INSN (olabel) | |
9cf49039 | 2090 | && GET_CODE (NEXT_INSN (olabel)) == NOTE |
2091 | && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END) | |
2092 | emit_note_after (NOTE_INSN_FUNCTION_END, nlabel); | |
2093 | ||
f8cacb57 | 2094 | if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused) |
e4bf866d | 2095 | delete_related_insns (olabel); |
5924de0b | 2096 | |
2097 | return 1; | |
2098 | } | |
2099 | ||
7113a566 | 2100 | /* Invert the jump condition of rtx X contained in jump insn, INSN. |
a8b5d014 | 2101 | Accrue the modifications into the change group. */ |
2102 | ||
2103 | static void | |
ba08b7e7 | 2104 | invert_exp_1 (insn) |
a8b5d014 | 2105 | rtx insn; |
2106 | { | |
19cb6b50 | 2107 | RTX_CODE code; |
ba08b7e7 | 2108 | rtx x = pc_set (insn); |
2109 | ||
2110 | if (!x) | |
7113a566 | 2111 | abort (); |
ba08b7e7 | 2112 | x = SET_SRC (x); |
a8b5d014 | 2113 | |
2114 | code = GET_CODE (x); | |
2115 | ||
2116 | if (code == IF_THEN_ELSE) | |
2117 | { | |
19cb6b50 | 2118 | rtx comp = XEXP (x, 0); |
2119 | rtx tem; | |
7da6ea0c | 2120 | enum rtx_code reversed_code; |
a8b5d014 | 2121 | |
2122 | /* We can do this in two ways: The preferable way, which can only | |
2123 | be done if this is not an integer comparison, is to reverse | |
2124 | the comparison code. Otherwise, swap the THEN-part and ELSE-part | |
2125 | of the IF_THEN_ELSE. If we can't do either, fail. */ | |
2126 | ||
7da6ea0c | 2127 | reversed_code = reversed_comparison_code (comp, insn); |
2128 | ||
2129 | if (reversed_code != UNKNOWN) | |
a8b5d014 | 2130 | { |
2131 | validate_change (insn, &XEXP (x, 0), | |
7da6ea0c | 2132 | gen_rtx_fmt_ee (reversed_code, |
a8b5d014 | 2133 | GET_MODE (comp), XEXP (comp, 0), |
2134 | XEXP (comp, 1)), | |
2135 | 1); | |
2136 | return; | |
2137 | } | |
7113a566 | 2138 | |
a8b5d014 | 2139 | tem = XEXP (x, 1); |
2140 | validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1); | |
2141 | validate_change (insn, &XEXP (x, 2), tem, 1); | |
a8b5d014 | 2142 | } |
ba08b7e7 | 2143 | else |
2144 | abort (); | |
a8b5d014 | 2145 | } |
2146 | ||
7113a566 | 2147 | /* Invert the jump condition of conditional jump insn, INSN. |
a8b5d014 | 2148 | |
2149 | Return 1 if we can do so, 0 if we cannot find a way to do so that | |
2150 | matches a pattern. */ | |
2151 | ||
ba08b7e7 | 2152 | static int |
2153 | invert_exp (insn) | |
a8b5d014 | 2154 | rtx insn; |
2155 | { | |
ba08b7e7 | 2156 | invert_exp_1 (insn); |
a8b5d014 | 2157 | if (num_validated_changes () == 0) |
2158 | return 0; | |
2159 | ||
2160 | return apply_change_group (); | |
2161 | } | |
2162 | ||
2163 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2164 | NLABEL instead of where it jumps now. Accrue changes into the | |
2165 | change group. Return false if we didn't see how to perform the | |
2166 | inversion and redirection. */ | |
2167 | ||
2168 | int | |
2169 | invert_jump_1 (jump, nlabel) | |
2170 | rtx jump, nlabel; | |
2171 | { | |
2172 | int ochanges; | |
2173 | ||
2174 | ochanges = num_validated_changes (); | |
ba08b7e7 | 2175 | invert_exp_1 (jump); |
a8b5d014 | 2176 | if (num_validated_changes () == ochanges) |
2177 | return 0; | |
2178 | ||
2179 | return redirect_jump_1 (jump, nlabel); | |
2180 | } | |
2181 | ||
2182 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2183 | NLABEL instead of where it jumps now. Return true if successful. */ | |
2184 | ||
2185 | int | |
f8cacb57 | 2186 | invert_jump (jump, nlabel, delete_unused) |
a8b5d014 | 2187 | rtx jump, nlabel; |
f8cacb57 | 2188 | int delete_unused; |
a8b5d014 | 2189 | { |
2190 | /* We have to either invert the condition and change the label or | |
2191 | do neither. Either operation could fail. We first try to invert | |
2192 | the jump. If that succeeds, we try changing the label. If that fails, | |
2193 | we invert the jump back to what it was. */ | |
2194 | ||
ba08b7e7 | 2195 | if (! invert_exp (jump)) |
a8b5d014 | 2196 | return 0; |
2197 | ||
f8cacb57 | 2198 | if (redirect_jump (jump, nlabel, delete_unused)) |
a8b5d014 | 2199 | { |
13488c51 | 2200 | invert_br_probabilities (jump); |
a8b5d014 | 2201 | |
2202 | return 1; | |
2203 | } | |
2204 | ||
ba08b7e7 | 2205 | if (! invert_exp (jump)) |
a8b5d014 | 2206 | /* This should just be putting it back the way it was. */ |
2207 | abort (); | |
2208 | ||
2209 | return 0; | |
2210 | } | |
2211 | ||
5924de0b | 2212 | \f |
2213 | /* Like rtx_equal_p except that it considers two REGs as equal | |
6c60c295 | 2214 | if they renumber to the same value and considers two commutative |
2215 | operations to be the same if the order of the operands has been | |
2207ad6a | 2216 | reversed. |
2217 | ||
2218 | ??? Addition is not commutative on the PA due to the weird implicit | |
2219 | space register selection rules for memory addresses. Therefore, we | |
2220 | don't consider a + b == b + a. | |
2221 | ||
2222 | We could/should make this test a little tighter. Possibly only | |
2223 | disabling it on the PA via some backend macro or only disabling this | |
2224 | case when the PLUS is inside a MEM. */ | |
5924de0b | 2225 | |
2226 | int | |
2227 | rtx_renumbered_equal_p (x, y) | |
2228 | rtx x, y; | |
2229 | { | |
19cb6b50 | 2230 | int i; |
2231 | RTX_CODE code = GET_CODE (x); | |
2232 | const char *fmt; | |
7113a566 | 2233 | |
5924de0b | 2234 | if (x == y) |
2235 | return 1; | |
6c60c295 | 2236 | |
5924de0b | 2237 | if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)) |
2238 | && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG | |
2239 | && GET_CODE (SUBREG_REG (y)) == REG))) | |
2240 | { | |
6c60c295 | 2241 | int reg_x = -1, reg_y = -1; |
701e46d0 | 2242 | int byte_x = 0, byte_y = 0; |
5924de0b | 2243 | |
2244 | if (GET_MODE (x) != GET_MODE (y)) | |
2245 | return 0; | |
2246 | ||
2247 | /* If we haven't done any renumbering, don't | |
2248 | make any assumptions. */ | |
2249 | if (reg_renumber == 0) | |
2250 | return rtx_equal_p (x, y); | |
2251 | ||
2252 | if (code == SUBREG) | |
2253 | { | |
6c60c295 | 2254 | reg_x = REGNO (SUBREG_REG (x)); |
701e46d0 | 2255 | byte_x = SUBREG_BYTE (x); |
6c60c295 | 2256 | |
2257 | if (reg_renumber[reg_x] >= 0) | |
2258 | { | |
701e46d0 | 2259 | reg_x = subreg_regno_offset (reg_renumber[reg_x], |
2260 | GET_MODE (SUBREG_REG (x)), | |
2261 | byte_x, | |
2262 | GET_MODE (x)); | |
2263 | byte_x = 0; | |
6c60c295 | 2264 | } |
5924de0b | 2265 | } |
2266 | else | |
2267 | { | |
6c60c295 | 2268 | reg_x = REGNO (x); |
2269 | if (reg_renumber[reg_x] >= 0) | |
2270 | reg_x = reg_renumber[reg_x]; | |
5924de0b | 2271 | } |
6c60c295 | 2272 | |
5924de0b | 2273 | if (GET_CODE (y) == SUBREG) |
2274 | { | |
6c60c295 | 2275 | reg_y = REGNO (SUBREG_REG (y)); |
701e46d0 | 2276 | byte_y = SUBREG_BYTE (y); |
6c60c295 | 2277 | |
2278 | if (reg_renumber[reg_y] >= 0) | |
2279 | { | |
701e46d0 | 2280 | reg_y = subreg_regno_offset (reg_renumber[reg_y], |
2281 | GET_MODE (SUBREG_REG (y)), | |
2282 | byte_y, | |
2283 | GET_MODE (y)); | |
2284 | byte_y = 0; | |
6c60c295 | 2285 | } |
5924de0b | 2286 | } |
2287 | else | |
2288 | { | |
6c60c295 | 2289 | reg_y = REGNO (y); |
2290 | if (reg_renumber[reg_y] >= 0) | |
2291 | reg_y = reg_renumber[reg_y]; | |
5924de0b | 2292 | } |
6c60c295 | 2293 | |
701e46d0 | 2294 | return reg_x >= 0 && reg_x == reg_y && byte_x == byte_y; |
5924de0b | 2295 | } |
6c60c295 | 2296 | |
7113a566 | 2297 | /* Now we have disposed of all the cases |
5924de0b | 2298 | in which different rtx codes can match. */ |
2299 | if (code != GET_CODE (y)) | |
2300 | return 0; | |
6c60c295 | 2301 | |
5924de0b | 2302 | switch (code) |
2303 | { | |
2304 | case PC: | |
2305 | case CC0: | |
2306 | case ADDR_VEC: | |
2307 | case ADDR_DIFF_VEC: | |
2308 | return 0; | |
2309 | ||
2310 | case CONST_INT: | |
5fbd420b | 2311 | return INTVAL (x) == INTVAL (y); |
5924de0b | 2312 | |
2313 | case LABEL_REF: | |
f08cae9d | 2314 | /* We can't assume nonlocal labels have their following insns yet. */ |
2315 | if (LABEL_REF_NONLOCAL_P (x) || LABEL_REF_NONLOCAL_P (y)) | |
2316 | return XEXP (x, 0) == XEXP (y, 0); | |
6c60c295 | 2317 | |
5924de0b | 2318 | /* Two label-refs are equivalent if they point at labels |
2319 | in the same position in the instruction stream. */ | |
2320 | return (next_real_insn (XEXP (x, 0)) | |
2321 | == next_real_insn (XEXP (y, 0))); | |
2322 | ||
2323 | case SYMBOL_REF: | |
2324 | return XSTR (x, 0) == XSTR (y, 0); | |
0dbd1c74 | 2325 | |
fc41ccae | 2326 | case CODE_LABEL: |
2327 | /* If we didn't match EQ equality above, they aren't the same. */ | |
2328 | return 0; | |
2329 | ||
0dbd1c74 | 2330 | default: |
2331 | break; | |
5924de0b | 2332 | } |
2333 | ||
2334 | /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ | |
2335 | ||
2336 | if (GET_MODE (x) != GET_MODE (y)) | |
2337 | return 0; | |
2338 | ||
6c60c295 | 2339 | /* For commutative operations, the RTX match if the operand match in any |
2207ad6a | 2340 | order. Also handle the simple binary and unary cases without a loop. |
2341 | ||
2342 | ??? Don't consider PLUS a commutative operator; see comments above. */ | |
2343 | if ((code == EQ || code == NE || GET_RTX_CLASS (code) == 'c') | |
2344 | && code != PLUS) | |
6c60c295 | 2345 | return ((rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) |
2346 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))) | |
2347 | || (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 1)) | |
2348 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 0)))); | |
2349 | else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2') | |
2350 | return (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) | |
2351 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))); | |
2352 | else if (GET_RTX_CLASS (code) == '1') | |
2353 | return rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)); | |
2354 | ||
5924de0b | 2355 | /* Compare the elements. If any pair of corresponding elements |
2356 | fail to match, return 0 for the whole things. */ | |
2357 | ||
2358 | fmt = GET_RTX_FORMAT (code); | |
2359 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
2360 | { | |
19cb6b50 | 2361 | int j; |
5924de0b | 2362 | switch (fmt[i]) |
2363 | { | |
1bb04728 | 2364 | case 'w': |
2365 | if (XWINT (x, i) != XWINT (y, i)) | |
2366 | return 0; | |
2367 | break; | |
2368 | ||
5924de0b | 2369 | case 'i': |
2370 | if (XINT (x, i) != XINT (y, i)) | |
2371 | return 0; | |
2372 | break; | |
2373 | ||
a0d79d69 | 2374 | case 't': |
2375 | if (XTREE (x, i) != XTREE (y, i)) | |
2376 | return 0; | |
2377 | break; | |
2378 | ||
5924de0b | 2379 | case 's': |
2380 | if (strcmp (XSTR (x, i), XSTR (y, i))) | |
2381 | return 0; | |
2382 | break; | |
2383 | ||
2384 | case 'e': | |
2385 | if (! rtx_renumbered_equal_p (XEXP (x, i), XEXP (y, i))) | |
2386 | return 0; | |
2387 | break; | |
2388 | ||
2389 | case 'u': | |
2390 | if (XEXP (x, i) != XEXP (y, i)) | |
2391 | return 0; | |
2392 | /* fall through. */ | |
2393 | case '0': | |
2394 | break; | |
2395 | ||
2396 | case 'E': | |
2397 | if (XVECLEN (x, i) != XVECLEN (y, i)) | |
2398 | return 0; | |
2399 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) | |
2400 | if (!rtx_renumbered_equal_p (XVECEXP (x, i, j), XVECEXP (y, i, j))) | |
2401 | return 0; | |
2402 | break; | |
2403 | ||
2404 | default: | |
2405 | abort (); | |
2406 | } | |
2407 | } | |
2408 | return 1; | |
2409 | } | |
2410 | \f | |
2411 | /* If X is a hard register or equivalent to one or a subregister of one, | |
2412 | return the hard register number. If X is a pseudo register that was not | |
2413 | assigned a hard register, return the pseudo register number. Otherwise, | |
2414 | return -1. Any rtx is valid for X. */ | |
2415 | ||
2416 | int | |
2417 | true_regnum (x) | |
2418 | rtx x; | |
2419 | { | |
2420 | if (GET_CODE (x) == REG) | |
2421 | { | |
2422 | if (REGNO (x) >= FIRST_PSEUDO_REGISTER && reg_renumber[REGNO (x)] >= 0) | |
2423 | return reg_renumber[REGNO (x)]; | |
2424 | return REGNO (x); | |
2425 | } | |
2426 | if (GET_CODE (x) == SUBREG) | |
2427 | { | |
2428 | int base = true_regnum (SUBREG_REG (x)); | |
2429 | if (base >= 0 && base < FIRST_PSEUDO_REGISTER) | |
701e46d0 | 2430 | return base + subreg_regno_offset (REGNO (SUBREG_REG (x)), |
2431 | GET_MODE (SUBREG_REG (x)), | |
2432 | SUBREG_BYTE (x), GET_MODE (x)); | |
5924de0b | 2433 | } |
2434 | return -1; | |
2435 | } |