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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 |
080f56ab | 3 | 1998, 1999, 2000, 2001, 2002 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))++; | |
fc4eaab7 | 94 | } |
95 | \f | |
fb3c15bc | 96 | /* Some old code expects exactly one BARRIER as the NEXT_INSN of a |
97 | non-fallthru insn. This is not generally true, as multiple barriers | |
98 | may have crept in, or the BARRIER may be separated from the last | |
99 | real insn by one or more NOTEs. | |
100 | ||
101 | This simple pass moves barriers and removes duplicates so that the | |
102 | old code is happy. | |
103 | */ | |
104 | void | |
105 | cleanup_barriers () | |
106 | { | |
107 | rtx insn, next, prev; | |
108 | for (insn = get_insns (); insn; insn = next) | |
109 | { | |
110 | next = NEXT_INSN (insn); | |
111 | if (GET_CODE (insn) == BARRIER) | |
112 | { | |
113 | prev = prev_nonnote_insn (insn); | |
114 | if (GET_CODE (prev) == BARRIER) | |
115 | delete_barrier (insn); | |
116 | else if (prev != PREV_INSN (insn)) | |
117 | reorder_insns (insn, insn, prev); | |
118 | } | |
119 | } | |
120 | } | |
121 | \f | |
fc4eaab7 | 122 | void |
123 | copy_loop_headers (f) | |
124 | rtx f; | |
125 | { | |
19cb6b50 | 126 | rtx insn, next; |
5924de0b | 127 | /* Now iterate optimizing jumps until nothing changes over one pass. */ |
fc4eaab7 | 128 | for (insn = f; insn; insn = next) |
5924de0b | 129 | { |
fc4eaab7 | 130 | rtx temp, temp1; |
5924de0b | 131 | |
fc4eaab7 | 132 | next = NEXT_INSN (insn); |
7014838c | 133 | |
fc4eaab7 | 134 | /* See if this is a NOTE_INSN_LOOP_BEG followed by an unconditional |
135 | jump. Try to optimize by duplicating the loop exit test if so. | |
136 | This is only safe immediately after regscan, because it uses | |
137 | the values of regno_first_uid and regno_last_uid. */ | |
138 | if (GET_CODE (insn) == NOTE | |
139 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG | |
140 | && (temp1 = next_nonnote_insn (insn)) != 0 | |
141 | && any_uncondjump_p (temp1) && onlyjump_p (temp1)) | |
142 | { | |
143 | temp = PREV_INSN (insn); | |
144 | if (duplicate_loop_exit_test (insn)) | |
5924de0b | 145 | { |
fc4eaab7 | 146 | next = NEXT_INSN (temp); |
5924de0b | 147 | } |
5924de0b | 148 | } |
5924de0b | 149 | } |
fc4eaab7 | 150 | } |
5924de0b | 151 | |
fc4eaab7 | 152 | void |
153 | purge_line_number_notes (f) | |
154 | rtx f; | |
155 | { | |
156 | rtx last_note = 0; | |
157 | rtx insn; | |
5924de0b | 158 | /* Delete extraneous line number notes. |
159 | Note that two consecutive notes for different lines are not really | |
160 | extraneous. There should be some indication where that line belonged, | |
161 | even if it became empty. */ | |
162 | ||
fc4eaab7 | 163 | for (insn = f; insn; insn = NEXT_INSN (insn)) |
164 | if (GET_CODE (insn) == NOTE) | |
165 | { | |
166 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG) | |
167 | /* Any previous line note was for the prologue; gdb wants a new | |
168 | note after the prologue even if it is for the same line. */ | |
169 | last_note = NULL_RTX; | |
170 | else if (NOTE_LINE_NUMBER (insn) >= 0) | |
171 | { | |
172 | /* Delete this note if it is identical to previous note. */ | |
173 | if (last_note | |
174 | && NOTE_SOURCE_FILE (insn) == NOTE_SOURCE_FILE (last_note) | |
175 | && NOTE_LINE_NUMBER (insn) == NOTE_LINE_NUMBER (last_note)) | |
176 | { | |
e4bf866d | 177 | delete_related_insns (insn); |
fc4eaab7 | 178 | continue; |
179 | } | |
5924de0b | 180 | |
fc4eaab7 | 181 | last_note = insn; |
182 | } | |
183 | } | |
e8d75e01 | 184 | } |
185 | \f | |
186 | /* Initialize LABEL_NUSES and JUMP_LABEL fields. Delete any REG_LABEL | |
187 | notes whose labels don't occur in the insn any more. Returns the | |
188 | largest INSN_UID found. */ | |
189 | static int | |
190 | init_label_info (f) | |
191 | rtx f; | |
192 | { | |
193 | int largest_uid = 0; | |
194 | rtx insn; | |
195 | ||
196 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
197 | { | |
198 | if (GET_CODE (insn) == CODE_LABEL) | |
199 | LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0); | |
200 | else if (GET_CODE (insn) == JUMP_INSN) | |
201 | JUMP_LABEL (insn) = 0; | |
202 | else if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
203 | { | |
204 | rtx note, next; | |
205 | ||
206 | for (note = REG_NOTES (insn); note; note = next) | |
207 | { | |
208 | next = XEXP (note, 1); | |
209 | if (REG_NOTE_KIND (note) == REG_LABEL | |
210 | && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn))) | |
211 | remove_note (insn, note); | |
212 | } | |
213 | } | |
214 | if (INSN_UID (insn) > largest_uid) | |
215 | largest_uid = INSN_UID (insn); | |
216 | } | |
217 | ||
218 | return largest_uid; | |
219 | } | |
220 | ||
e8d75e01 | 221 | /* Mark the label each jump jumps to. |
fc4eaab7 | 222 | Combine consecutive labels, and count uses of labels. */ |
e8d75e01 | 223 | |
224 | static void | |
bf73fcf4 | 225 | mark_all_labels (f) |
e8d75e01 | 226 | rtx f; |
e8d75e01 | 227 | { |
228 | rtx insn; | |
229 | ||
230 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
9204e736 | 231 | if (INSN_P (insn)) |
e8d75e01 | 232 | { |
0e3150ce | 233 | if (GET_CODE (insn) == CALL_INSN |
234 | && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) | |
235 | { | |
bf73fcf4 | 236 | mark_all_labels (XEXP (PATTERN (insn), 0)); |
237 | mark_all_labels (XEXP (PATTERN (insn), 1)); | |
238 | mark_all_labels (XEXP (PATTERN (insn), 2)); | |
af29e037 | 239 | |
240 | /* Canonicalize the tail recursion label attached to the | |
241 | CALL_PLACEHOLDER insn. */ | |
242 | if (XEXP (PATTERN (insn), 3)) | |
243 | { | |
244 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
245 | XEXP (PATTERN (insn), 3)); | |
bf73fcf4 | 246 | mark_jump_label (label_ref, insn, 0); |
af29e037 | 247 | XEXP (PATTERN (insn), 3) = XEXP (label_ref, 0); |
248 | } | |
249 | ||
0e3150ce | 250 | continue; |
251 | } | |
7113a566 | 252 | |
bf73fcf4 | 253 | mark_jump_label (PATTERN (insn), insn, 0); |
e8d75e01 | 254 | if (! INSN_DELETED_P (insn) && GET_CODE (insn) == JUMP_INSN) |
255 | { | |
d3ff0f75 | 256 | /* When we know the LABEL_REF contained in a REG used in |
257 | an indirect jump, we'll have a REG_LABEL note so that | |
258 | flow can tell where it's going. */ | |
259 | if (JUMP_LABEL (insn) == 0) | |
260 | { | |
261 | rtx label_note = find_reg_note (insn, REG_LABEL, NULL_RTX); | |
262 | if (label_note) | |
263 | { | |
264 | /* But a LABEL_REF around the REG_LABEL note, so | |
265 | that we can canonicalize it. */ | |
266 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
267 | XEXP (label_note, 0)); | |
268 | ||
bf73fcf4 | 269 | mark_jump_label (label_ref, insn, 0); |
d3ff0f75 | 270 | XEXP (label_note, 0) = XEXP (label_ref, 0); |
271 | JUMP_LABEL (insn) = XEXP (label_note, 0); | |
272 | } | |
273 | } | |
e8d75e01 | 274 | } |
275 | } | |
276 | } | |
277 | ||
5924de0b | 278 | /* LOOP_START is a NOTE_INSN_LOOP_BEG note that is followed by an unconditional |
279 | jump. Assume that this unconditional jump is to the exit test code. If | |
280 | the code is sufficiently simple, make a copy of it before INSN, | |
281 | followed by a jump to the exit of the loop. Then delete the unconditional | |
282 | jump after INSN. | |
283 | ||
5924de0b | 284 | Return 1 if we made the change, else 0. |
285 | ||
286 | This is only safe immediately after a regscan pass because it uses the | |
287 | values of regno_first_uid and regno_last_uid. */ | |
288 | ||
289 | static int | |
290 | duplicate_loop_exit_test (loop_start) | |
291 | rtx loop_start; | |
292 | { | |
3a348c93 | 293 | rtx insn, set, reg, p, link; |
4e717234 | 294 | rtx copy = 0, first_copy = 0; |
5924de0b | 295 | int num_insns = 0; |
296 | rtx exitcode = NEXT_INSN (JUMP_LABEL (next_nonnote_insn (loop_start))); | |
297 | rtx lastexit; | |
298 | int max_reg = max_reg_num (); | |
299 | rtx *reg_map = 0; | |
ea918419 | 300 | rtx loop_pre_header_label; |
5924de0b | 301 | |
302 | /* Scan the exit code. We do not perform this optimization if any insn: | |
303 | ||
304 | is a CALL_INSN | |
305 | is a CODE_LABEL | |
306 | has a REG_RETVAL or REG_LIBCALL note (hard to adjust) | |
307 | is a NOTE_INSN_LOOP_BEG because this means we have a nested loop | |
17b1950c | 308 | |
309 | We also do not do this if we find an insn with ASM_OPERANDS. While | |
310 | this restriction should not be necessary, copying an insn with | |
311 | ASM_OPERANDS can confuse asm_noperands in some cases. | |
5924de0b | 312 | |
313 | Also, don't do this if the exit code is more than 20 insns. */ | |
314 | ||
315 | for (insn = exitcode; | |
316 | insn | |
317 | && ! (GET_CODE (insn) == NOTE | |
318 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END); | |
319 | insn = NEXT_INSN (insn)) | |
320 | { | |
321 | switch (GET_CODE (insn)) | |
322 | { | |
323 | case CODE_LABEL: | |
324 | case CALL_INSN: | |
325 | return 0; | |
326 | case NOTE: | |
ec6be638 | 327 | |
328 | if (optimize < 2 | |
329 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
330 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)) | |
331 | /* If we were to duplicate this code, we would not move | |
332 | the BLOCK notes, and so debugging the moved code would | |
333 | be difficult. Thus, we only move the code with -O2 or | |
334 | higher. */ | |
335 | return 0; | |
336 | ||
5924de0b | 337 | break; |
338 | case JUMP_INSN: | |
339 | case INSN: | |
7665c376 | 340 | /* The code below would grossly mishandle REG_WAS_0 notes, |
341 | so get rid of them here. */ | |
342 | while ((p = find_reg_note (insn, REG_WAS_0, NULL_RTX)) != 0) | |
343 | remove_note (insn, p); | |
5924de0b | 344 | if (++num_insns > 20 |
1bb04728 | 345 | || find_reg_note (insn, REG_RETVAL, NULL_RTX) |
928d57e3 | 346 | || find_reg_note (insn, REG_LIBCALL, NULL_RTX)) |
5924de0b | 347 | return 0; |
348 | break; | |
0dbd1c74 | 349 | default: |
350 | break; | |
5924de0b | 351 | } |
352 | } | |
353 | ||
354 | /* Unless INSN is zero, we can do the optimization. */ | |
355 | if (insn == 0) | |
356 | return 0; | |
357 | ||
358 | lastexit = insn; | |
359 | ||
360 | /* See if any insn sets a register only used in the loop exit code and | |
361 | not a user variable. If so, replace it with a new register. */ | |
362 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
363 | if (GET_CODE (insn) == INSN | |
364 | && (set = single_set (insn)) != 0 | |
3a348c93 | 365 | && ((reg = SET_DEST (set), GET_CODE (reg) == REG) |
366 | || (GET_CODE (reg) == SUBREG | |
367 | && (reg = SUBREG_REG (reg), GET_CODE (reg) == REG))) | |
368 | && REGNO (reg) >= FIRST_PSEUDO_REGISTER | |
394685a4 | 369 | && REGNO_FIRST_UID (REGNO (reg)) == INSN_UID (insn)) |
5924de0b | 370 | { |
371 | for (p = NEXT_INSN (insn); p != lastexit; p = NEXT_INSN (p)) | |
394685a4 | 372 | if (REGNO_LAST_UID (REGNO (reg)) == INSN_UID (p)) |
5924de0b | 373 | break; |
374 | ||
375 | if (p != lastexit) | |
376 | { | |
377 | /* We can do the replacement. Allocate reg_map if this is the | |
378 | first replacement we found. */ | |
379 | if (reg_map == 0) | |
8b861be4 | 380 | reg_map = (rtx *) xcalloc (max_reg, sizeof (rtx)); |
5924de0b | 381 | |
3a348c93 | 382 | REG_LOOP_TEST_P (reg) = 1; |
5924de0b | 383 | |
3a348c93 | 384 | reg_map[REGNO (reg)] = gen_reg_rtx (GET_MODE (reg)); |
5924de0b | 385 | } |
386 | } | |
ea918419 | 387 | loop_pre_header_label = gen_label_rtx (); |
5924de0b | 388 | |
389 | /* Now copy each insn. */ | |
390 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
4e717234 | 391 | { |
392 | switch (GET_CODE (insn)) | |
393 | { | |
394 | case BARRIER: | |
395 | copy = emit_barrier_before (loop_start); | |
396 | break; | |
397 | case NOTE: | |
398 | /* Only copy line-number notes. */ | |
399 | if (NOTE_LINE_NUMBER (insn) >= 0) | |
400 | { | |
401 | copy = emit_note_before (NOTE_LINE_NUMBER (insn), loop_start); | |
402 | NOTE_SOURCE_FILE (copy) = NOTE_SOURCE_FILE (insn); | |
403 | } | |
404 | break; | |
7113a566 | 405 | |
4e717234 | 406 | case INSN: |
928d57e3 | 407 | copy = emit_insn_before (copy_insn (PATTERN (insn)), loop_start); |
4e717234 | 408 | if (reg_map) |
409 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
7113a566 | 410 | |
bf73fcf4 | 411 | mark_jump_label (PATTERN (copy), copy, 0); |
ab87d1bc | 412 | INSN_SCOPE (copy) = INSN_SCOPE (insn); |
7113a566 | 413 | |
4e717234 | 414 | /* Copy all REG_NOTES except REG_LABEL since mark_jump_label will |
415 | make them. */ | |
416 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
417 | if (REG_NOTE_KIND (link) != REG_LABEL) | |
74b0991d | 418 | { |
419 | if (GET_CODE (link) == EXPR_LIST) | |
420 | REG_NOTES (copy) | |
421 | = copy_insn_1 (gen_rtx_EXPR_LIST (REG_NOTE_KIND (link), | |
422 | XEXP (link, 0), | |
423 | REG_NOTES (copy))); | |
424 | else | |
425 | REG_NOTES (copy) | |
426 | = copy_insn_1 (gen_rtx_INSN_LIST (REG_NOTE_KIND (link), | |
427 | XEXP (link, 0), | |
428 | REG_NOTES (copy))); | |
429 | } | |
430 | ||
4e717234 | 431 | if (reg_map && REG_NOTES (copy)) |
432 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
433 | break; | |
7113a566 | 434 | |
4e717234 | 435 | case JUMP_INSN: |
7113a566 | 436 | copy = emit_jump_insn_before (copy_insn (PATTERN (insn)), |
437 | loop_start); | |
ab87d1bc | 438 | INSN_SCOPE (copy) = INSN_SCOPE (insn); |
4e717234 | 439 | if (reg_map) |
440 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
bf73fcf4 | 441 | mark_jump_label (PATTERN (copy), copy, 0); |
4e717234 | 442 | if (REG_NOTES (insn)) |
443 | { | |
928d57e3 | 444 | REG_NOTES (copy) = copy_insn_1 (REG_NOTES (insn)); |
4e717234 | 445 | if (reg_map) |
446 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
447 | } | |
7113a566 | 448 | |
13488c51 | 449 | /* Predict conditional jump that do make loop looping as taken. |
450 | Other jumps are probably exit conditions, so predict | |
451 | them as untaken. */ | |
452 | if (any_condjump_p (copy)) | |
453 | { | |
454 | rtx label = JUMP_LABEL (copy); | |
455 | if (label) | |
456 | { | |
4361b500 | 457 | /* The jump_insn after loop_start should be followed |
458 | by barrier and loopback label. */ | |
459 | if (prev_nonnote_insn (label) | |
ea918419 | 460 | && (prev_nonnote_insn (prev_nonnote_insn (label)) |
461 | == next_nonnote_insn (loop_start))) | |
462 | { | |
463 | predict_insn_def (copy, PRED_LOOP_HEADER, TAKEN); | |
464 | /* To keep pre-header, we need to redirect all loop | |
465 | entrances before the LOOP_BEG note. */ | |
466 | redirect_jump (copy, loop_pre_header_label, 0); | |
467 | } | |
13488c51 | 468 | else |
469 | predict_insn_def (copy, PRED_LOOP_HEADER, NOT_TAKEN); | |
470 | } | |
471 | } | |
4e717234 | 472 | break; |
7113a566 | 473 | |
4e717234 | 474 | default: |
475 | abort (); | |
476 | } | |
5924de0b | 477 | |
4e717234 | 478 | /* Record the first insn we copied. We need it so that we can |
479 | scan the copied insns for new pseudo registers. */ | |
480 | if (! first_copy) | |
481 | first_copy = copy; | |
482 | } | |
5924de0b | 483 | |
484 | /* Now clean up by emitting a jump to the end label and deleting the jump | |
485 | at the start of the loop. */ | |
b8778d98 | 486 | if (! copy || GET_CODE (copy) != BARRIER) |
5924de0b | 487 | { |
488 | copy = emit_jump_insn_before (gen_jump (get_label_after (insn)), | |
489 | loop_start); | |
4e717234 | 490 | |
491 | /* Record the first insn we copied. We need it so that we can | |
492 | scan the copied insns for new pseudo registers. This may not | |
493 | be strictly necessary since we should have copied at least one | |
494 | insn above. But I am going to be safe. */ | |
495 | if (! first_copy) | |
496 | first_copy = copy; | |
497 | ||
bf73fcf4 | 498 | mark_jump_label (PATTERN (copy), copy, 0); |
5924de0b | 499 | emit_barrier_before (loop_start); |
500 | } | |
501 | ||
ea918419 | 502 | emit_label_before (loop_pre_header_label, loop_start); |
503 | ||
4e717234 | 504 | /* Now scan from the first insn we copied to the last insn we copied |
505 | (copy) for new pseudo registers. Do this after the code to jump to | |
506 | the end label since that might create a new pseudo too. */ | |
507 | reg_scan_update (first_copy, copy, max_reg); | |
508 | ||
5924de0b | 509 | /* Mark the exit code as the virtual top of the converted loop. */ |
510 | emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode); | |
511 | ||
e4bf866d | 512 | delete_related_insns (next_nonnote_insn (loop_start)); |
7113a566 | 513 | |
8b861be4 | 514 | /* Clean up. */ |
515 | if (reg_map) | |
516 | free (reg_map); | |
92d3c3ad | 517 | |
5924de0b | 518 | return 1; |
519 | } | |
520 | \f | |
74b0991d | 521 | /* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-end, |
3612339f | 522 | notes between START and END out before START. START and END may be such |
523 | notes. Returns the values of the new starting and ending insns, which | |
87dc0300 | 524 | may be different if the original ones were such notes. |
525 | Return true if there were only such notes and no real instructions. */ | |
5924de0b | 526 | |
87dc0300 | 527 | bool |
3612339f | 528 | squeeze_notes (startp, endp) |
529 | rtx* startp; | |
530 | rtx* endp; | |
5924de0b | 531 | { |
3612339f | 532 | rtx start = *startp; |
533 | rtx end = *endp; | |
534 | ||
5924de0b | 535 | rtx insn; |
536 | rtx next; | |
3612339f | 537 | rtx last = NULL; |
538 | rtx past_end = NEXT_INSN (end); | |
5924de0b | 539 | |
3612339f | 540 | for (insn = start; insn != past_end; insn = next) |
5924de0b | 541 | { |
542 | next = NEXT_INSN (insn); | |
543 | if (GET_CODE (insn) == NOTE | |
544 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END | |
545 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
546 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG | |
547 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END | |
548 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT | |
a196d160 | 549 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_VTOP)) |
5924de0b | 550 | { |
d2d45541 | 551 | if (insn == start) |
552 | start = next; | |
553 | else | |
554 | { | |
555 | rtx prev = PREV_INSN (insn); | |
556 | PREV_INSN (insn) = PREV_INSN (start); | |
557 | NEXT_INSN (insn) = start; | |
558 | NEXT_INSN (PREV_INSN (insn)) = insn; | |
559 | PREV_INSN (NEXT_INSN (insn)) = insn; | |
560 | NEXT_INSN (prev) = next; | |
561 | PREV_INSN (next) = prev; | |
562 | } | |
5924de0b | 563 | } |
3612339f | 564 | else |
565 | last = insn; | |
5924de0b | 566 | } |
d2d45541 | 567 | |
87dc0300 | 568 | /* There were no real instructions. */ |
3612339f | 569 | if (start == past_end) |
87dc0300 | 570 | return true; |
3612339f | 571 | |
572 | end = last; | |
573 | ||
574 | *startp = start; | |
575 | *endp = end; | |
87dc0300 | 576 | return false; |
5924de0b | 577 | } |
578 | \f | |
5924de0b | 579 | /* Return the label before INSN, or put a new label there. */ |
580 | ||
581 | rtx | |
582 | get_label_before (insn) | |
583 | rtx insn; | |
584 | { | |
585 | rtx label; | |
586 | ||
587 | /* Find an existing label at this point | |
588 | or make a new one if there is none. */ | |
589 | label = prev_nonnote_insn (insn); | |
590 | ||
591 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
592 | { | |
593 | rtx prev = PREV_INSN (insn); | |
594 | ||
5924de0b | 595 | label = gen_label_rtx (); |
596 | emit_label_after (label, prev); | |
597 | LABEL_NUSES (label) = 0; | |
598 | } | |
599 | return label; | |
600 | } | |
601 | ||
602 | /* Return the label after INSN, or put a new label there. */ | |
603 | ||
604 | rtx | |
605 | get_label_after (insn) | |
606 | rtx insn; | |
607 | { | |
608 | rtx label; | |
609 | ||
610 | /* Find an existing label at this point | |
611 | or make a new one if there is none. */ | |
612 | label = next_nonnote_insn (insn); | |
613 | ||
614 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
615 | { | |
5924de0b | 616 | label = gen_label_rtx (); |
617 | emit_label_after (label, insn); | |
618 | LABEL_NUSES (label) = 0; | |
619 | } | |
620 | return label; | |
621 | } | |
622 | \f | |
fa8b3d85 | 623 | /* Given a comparison (CODE ARG0 ARG1), inside an insn, INSN, return a code |
8e98892d | 624 | of reversed comparison if it is possible to do so. Otherwise return UNKNOWN. |
625 | UNKNOWN may be returned in case we are having CC_MODE compare and we don't | |
626 | know whether it's source is floating point or integer comparison. Machine | |
627 | description should define REVERSIBLE_CC_MODE and REVERSE_CONDITION macros | |
628 | to help this function avoid overhead in these cases. */ | |
629 | enum rtx_code | |
630 | reversed_comparison_code_parts (code, arg0, arg1, insn) | |
631 | rtx insn, arg0, arg1; | |
632 | enum rtx_code code; | |
5924de0b | 633 | { |
8e98892d | 634 | enum machine_mode mode; |
5924de0b | 635 | |
636 | /* If this is not actually a comparison, we can't reverse it. */ | |
8e98892d | 637 | if (GET_RTX_CLASS (code) != '<') |
638 | return UNKNOWN; | |
639 | ||
640 | mode = GET_MODE (arg0); | |
641 | if (mode == VOIDmode) | |
642 | mode = GET_MODE (arg1); | |
643 | ||
644 | /* First see if machine description supply us way to reverse the comparison. | |
645 | Give it priority over everything else to allow machine description to do | |
646 | tricks. */ | |
647 | #ifdef REVERSIBLE_CC_MODE | |
0ec244e1 | 648 | if (GET_MODE_CLASS (mode) == MODE_CC |
8e98892d | 649 | && REVERSIBLE_CC_MODE (mode)) |
650 | { | |
651 | #ifdef REVERSE_CONDITION | |
85fc0ad1 | 652 | return REVERSE_CONDITION (code, mode); |
8e98892d | 653 | #endif |
85fc0ad1 | 654 | return reverse_condition (code); |
655 | } | |
8e98892d | 656 | #endif |
5924de0b | 657 | |
fa8b3d85 | 658 | /* Try a few special cases based on the comparison code. */ |
8e98892d | 659 | switch (code) |
660 | { | |
85fc0ad1 | 661 | case GEU: |
662 | case GTU: | |
663 | case LEU: | |
664 | case LTU: | |
665 | case NE: | |
666 | case EQ: | |
667 | /* It is always safe to reverse EQ and NE, even for the floating | |
668 | point. Similary the unsigned comparisons are never used for | |
669 | floating point so we can reverse them in the default way. */ | |
670 | return reverse_condition (code); | |
671 | case ORDERED: | |
672 | case UNORDERED: | |
673 | case LTGT: | |
674 | case UNEQ: | |
675 | /* In case we already see unordered comparison, we can be sure to | |
676 | be dealing with floating point so we don't need any more tests. */ | |
677 | return reverse_condition_maybe_unordered (code); | |
678 | case UNLT: | |
679 | case UNLE: | |
680 | case UNGT: | |
681 | case UNGE: | |
682 | /* We don't have safe way to reverse these yet. */ | |
683 | return UNKNOWN; | |
684 | default: | |
685 | break; | |
8e98892d | 686 | } |
687 | ||
8e98892d | 688 | if (GET_MODE_CLASS (mode) == MODE_CC |
5924de0b | 689 | #ifdef HAVE_cc0 |
690 | || arg0 == cc0_rtx | |
691 | #endif | |
692 | ) | |
693 | { | |
8e98892d | 694 | rtx prev; |
695 | /* Try to search for the comparison to determine the real mode. | |
696 | This code is expensive, but with sane machine description it | |
697 | will be never used, since REVERSIBLE_CC_MODE will return true | |
698 | in all cases. */ | |
111f2389 | 699 | if (! insn) |
8e98892d | 700 | return UNKNOWN; |
7113a566 | 701 | |
7014838c | 702 | for (prev = prev_nonnote_insn (insn); |
703 | prev != 0 && GET_CODE (prev) != CODE_LABEL; | |
704 | prev = prev_nonnote_insn (prev)) | |
8e98892d | 705 | { |
706 | rtx set = set_of (arg0, prev); | |
707 | if (set && GET_CODE (set) == SET | |
708 | && rtx_equal_p (SET_DEST (set), arg0)) | |
709 | { | |
710 | rtx src = SET_SRC (set); | |
5924de0b | 711 | |
8e98892d | 712 | if (GET_CODE (src) == COMPARE) |
713 | { | |
714 | rtx comparison = src; | |
715 | arg0 = XEXP (src, 0); | |
716 | mode = GET_MODE (arg0); | |
717 | if (mode == VOIDmode) | |
718 | mode = GET_MODE (XEXP (comparison, 1)); | |
719 | break; | |
720 | } | |
dd5b4b36 | 721 | /* We can get past reg-reg moves. This may be useful for model |
8e98892d | 722 | of i387 comparisons that first move flag registers around. */ |
723 | if (REG_P (src)) | |
724 | { | |
725 | arg0 = src; | |
726 | continue; | |
727 | } | |
728 | } | |
729 | /* If register is clobbered in some ununderstandable way, | |
730 | give up. */ | |
731 | if (set) | |
732 | return UNKNOWN; | |
733 | } | |
5924de0b | 734 | } |
735 | ||
920d0fb5 | 736 | /* Test for an integer condition, or a floating-point comparison |
737 | in which NaNs can be ignored. */ | |
8e98892d | 738 | if (GET_CODE (arg0) == CONST_INT |
739 | || (GET_MODE (arg0) != VOIDmode | |
740 | && GET_MODE_CLASS (mode) != MODE_CC | |
920d0fb5 | 741 | && !HONOR_NANS (mode))) |
8e98892d | 742 | return reverse_condition (code); |
743 | ||
744 | return UNKNOWN; | |
745 | } | |
746 | ||
747 | /* An wrapper around the previous function to take COMPARISON as rtx | |
748 | expression. This simplifies many callers. */ | |
749 | enum rtx_code | |
750 | reversed_comparison_code (comparison, insn) | |
751 | rtx comparison, insn; | |
752 | { | |
753 | if (GET_RTX_CLASS (GET_CODE (comparison)) != '<') | |
754 | return UNKNOWN; | |
755 | return reversed_comparison_code_parts (GET_CODE (comparison), | |
756 | XEXP (comparison, 0), | |
757 | XEXP (comparison, 1), insn); | |
758 | } | |
759 | \f | |
a4110d9a | 760 | /* Given an rtx-code for a comparison, return the code for the negated |
761 | comparison. If no such code exists, return UNKNOWN. | |
762 | ||
763 | WATCH OUT! reverse_condition is not safe to use on a jump that might | |
764 | be acting on the results of an IEEE floating point comparison, because | |
7113a566 | 765 | of the special treatment of non-signaling nans in comparisons. |
8e98892d | 766 | Use reversed_comparison_code instead. */ |
5924de0b | 767 | |
768 | enum rtx_code | |
769 | reverse_condition (code) | |
770 | enum rtx_code code; | |
771 | { | |
772 | switch (code) | |
773 | { | |
774 | case EQ: | |
775 | return NE; | |
5924de0b | 776 | case NE: |
777 | return EQ; | |
5924de0b | 778 | case GT: |
779 | return LE; | |
5924de0b | 780 | case GE: |
781 | return LT; | |
5924de0b | 782 | case LT: |
783 | return GE; | |
5924de0b | 784 | case LE: |
785 | return GT; | |
5924de0b | 786 | case GTU: |
787 | return LEU; | |
5924de0b | 788 | case GEU: |
789 | return LTU; | |
5924de0b | 790 | case LTU: |
791 | return GEU; | |
5924de0b | 792 | case LEU: |
793 | return GTU; | |
a4110d9a | 794 | case UNORDERED: |
795 | return ORDERED; | |
796 | case ORDERED: | |
797 | return UNORDERED; | |
798 | ||
799 | case UNLT: | |
800 | case UNLE: | |
801 | case UNGT: | |
802 | case UNGE: | |
803 | case UNEQ: | |
79777bad | 804 | case LTGT: |
a4110d9a | 805 | return UNKNOWN; |
5924de0b | 806 | |
807 | default: | |
808 | abort (); | |
5924de0b | 809 | } |
810 | } | |
811 | ||
79777bad | 812 | /* Similar, but we're allowed to generate unordered comparisons, which |
813 | makes it safe for IEEE floating-point. Of course, we have to recognize | |
814 | that the target will support them too... */ | |
815 | ||
816 | enum rtx_code | |
817 | reverse_condition_maybe_unordered (code) | |
818 | enum rtx_code code; | |
819 | { | |
79777bad | 820 | switch (code) |
821 | { | |
822 | case EQ: | |
823 | return NE; | |
824 | case NE: | |
825 | return EQ; | |
826 | case GT: | |
827 | return UNLE; | |
828 | case GE: | |
829 | return UNLT; | |
830 | case LT: | |
831 | return UNGE; | |
832 | case LE: | |
833 | return UNGT; | |
834 | case LTGT: | |
835 | return UNEQ; | |
79777bad | 836 | case UNORDERED: |
837 | return ORDERED; | |
838 | case ORDERED: | |
839 | return UNORDERED; | |
840 | case UNLT: | |
841 | return GE; | |
842 | case UNLE: | |
843 | return GT; | |
844 | case UNGT: | |
845 | return LE; | |
846 | case UNGE: | |
847 | return LT; | |
848 | case UNEQ: | |
849 | return LTGT; | |
850 | ||
851 | default: | |
852 | abort (); | |
853 | } | |
854 | } | |
855 | ||
5924de0b | 856 | /* Similar, but return the code when two operands of a comparison are swapped. |
857 | This IS safe for IEEE floating-point. */ | |
858 | ||
859 | enum rtx_code | |
860 | swap_condition (code) | |
861 | enum rtx_code code; | |
862 | { | |
863 | switch (code) | |
864 | { | |
865 | case EQ: | |
866 | case NE: | |
a4110d9a | 867 | case UNORDERED: |
868 | case ORDERED: | |
869 | case UNEQ: | |
79777bad | 870 | case LTGT: |
5924de0b | 871 | return code; |
872 | ||
873 | case GT: | |
874 | return LT; | |
5924de0b | 875 | case GE: |
876 | return LE; | |
5924de0b | 877 | case LT: |
878 | return GT; | |
5924de0b | 879 | case LE: |
880 | return GE; | |
5924de0b | 881 | case GTU: |
882 | return LTU; | |
5924de0b | 883 | case GEU: |
884 | return LEU; | |
5924de0b | 885 | case LTU: |
886 | return GTU; | |
5924de0b | 887 | case LEU: |
888 | return GEU; | |
a4110d9a | 889 | case UNLT: |
890 | return UNGT; | |
891 | case UNLE: | |
892 | return UNGE; | |
893 | case UNGT: | |
894 | return UNLT; | |
895 | case UNGE: | |
896 | return UNLE; | |
897 | ||
5924de0b | 898 | default: |
899 | abort (); | |
5924de0b | 900 | } |
901 | } | |
902 | ||
903 | /* Given a comparison CODE, return the corresponding unsigned comparison. | |
904 | If CODE is an equality comparison or already an unsigned comparison, | |
905 | CODE is returned. */ | |
906 | ||
907 | enum rtx_code | |
908 | unsigned_condition (code) | |
909 | enum rtx_code code; | |
910 | { | |
911 | switch (code) | |
912 | { | |
913 | case EQ: | |
914 | case NE: | |
915 | case GTU: | |
916 | case GEU: | |
917 | case LTU: | |
918 | case LEU: | |
919 | return code; | |
920 | ||
921 | case GT: | |
922 | return GTU; | |
5924de0b | 923 | case GE: |
924 | return GEU; | |
5924de0b | 925 | case LT: |
926 | return LTU; | |
5924de0b | 927 | case LE: |
928 | return LEU; | |
929 | ||
930 | default: | |
931 | abort (); | |
932 | } | |
933 | } | |
934 | ||
935 | /* Similarly, return the signed version of a comparison. */ | |
936 | ||
937 | enum rtx_code | |
938 | signed_condition (code) | |
939 | enum rtx_code code; | |
940 | { | |
941 | switch (code) | |
942 | { | |
943 | case EQ: | |
944 | case NE: | |
945 | case GT: | |
946 | case GE: | |
947 | case LT: | |
948 | case LE: | |
949 | return code; | |
950 | ||
951 | case GTU: | |
952 | return GT; | |
5924de0b | 953 | case GEU: |
954 | return GE; | |
5924de0b | 955 | case LTU: |
956 | return LT; | |
5924de0b | 957 | case LEU: |
958 | return LE; | |
959 | ||
960 | default: | |
961 | abort (); | |
962 | } | |
963 | } | |
964 | \f | |
6ef828f9 | 965 | /* Return nonzero if CODE1 is more strict than CODE2, i.e., if the |
5924de0b | 966 | truth of CODE1 implies the truth of CODE2. */ |
967 | ||
968 | int | |
969 | comparison_dominates_p (code1, code2) | |
970 | enum rtx_code code1, code2; | |
971 | { | |
ca7744c6 | 972 | /* UNKNOWN comparison codes can happen as a result of trying to revert |
973 | comparison codes. | |
974 | They can't match anything, so we have to reject them here. */ | |
975 | if (code1 == UNKNOWN || code2 == UNKNOWN) | |
976 | return 0; | |
977 | ||
5924de0b | 978 | if (code1 == code2) |
979 | return 1; | |
980 | ||
981 | switch (code1) | |
982 | { | |
5aa3f5e2 | 983 | case UNEQ: |
984 | if (code2 == UNLE || code2 == UNGE) | |
985 | return 1; | |
986 | break; | |
987 | ||
5924de0b | 988 | case EQ: |
79777bad | 989 | if (code2 == LE || code2 == LEU || code2 == GE || code2 == GEU |
990 | || code2 == ORDERED) | |
5924de0b | 991 | return 1; |
992 | break; | |
993 | ||
5aa3f5e2 | 994 | case UNLT: |
995 | if (code2 == UNLE || code2 == NE) | |
996 | return 1; | |
997 | break; | |
998 | ||
5924de0b | 999 | case LT: |
5aa3f5e2 | 1000 | if (code2 == LE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
1001 | return 1; | |
1002 | break; | |
1003 | ||
1004 | case UNGT: | |
1005 | if (code2 == UNGE || code2 == NE) | |
5924de0b | 1006 | return 1; |
1007 | break; | |
1008 | ||
1009 | case GT: | |
5aa3f5e2 | 1010 | if (code2 == GE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
79777bad | 1011 | return 1; |
1012 | break; | |
1013 | ||
1014 | case GE: | |
1015 | case LE: | |
1016 | if (code2 == ORDERED) | |
1017 | return 1; | |
1018 | break; | |
1019 | ||
1020 | case LTGT: | |
1021 | if (code2 == NE || code2 == ORDERED) | |
5924de0b | 1022 | return 1; |
1023 | break; | |
1024 | ||
1025 | case LTU: | |
11088b43 | 1026 | if (code2 == LEU || code2 == NE) |
5924de0b | 1027 | return 1; |
1028 | break; | |
1029 | ||
1030 | case GTU: | |
11088b43 | 1031 | if (code2 == GEU || code2 == NE) |
5924de0b | 1032 | return 1; |
1033 | break; | |
79777bad | 1034 | |
1035 | case UNORDERED: | |
5aa3f5e2 | 1036 | if (code2 == NE || code2 == UNEQ || code2 == UNLE || code2 == UNLT |
1037 | || code2 == UNGE || code2 == UNGT) | |
79777bad | 1038 | return 1; |
1039 | break; | |
7113a566 | 1040 | |
0dbd1c74 | 1041 | default: |
1042 | break; | |
5924de0b | 1043 | } |
1044 | ||
1045 | return 0; | |
1046 | } | |
1047 | \f | |
1048 | /* Return 1 if INSN is an unconditional jump and nothing else. */ | |
1049 | ||
1050 | int | |
1051 | simplejump_p (insn) | |
1052 | rtx insn; | |
1053 | { | |
8d472058 | 1054 | return (GET_CODE (insn) == JUMP_INSN |
1055 | && GET_CODE (PATTERN (insn)) == SET | |
1056 | && GET_CODE (SET_DEST (PATTERN (insn))) == PC | |
1057 | && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF); | |
5924de0b | 1058 | } |
1059 | ||
1060 | /* Return nonzero if INSN is a (possibly) conditional jump | |
7113a566 | 1061 | and nothing more. |
1062 | ||
d670e794 | 1063 | Use this function is deprecated, since we need to support combined |
1064 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
5924de0b | 1065 | |
1066 | int | |
1067 | condjump_p (insn) | |
1068 | rtx insn; | |
1069 | { | |
19cb6b50 | 1070 | rtx x = PATTERN (insn); |
7014838c | 1071 | |
1072 | if (GET_CODE (x) != SET | |
1073 | || GET_CODE (SET_DEST (x)) != PC) | |
4fbe8fa7 | 1074 | return 0; |
7014838c | 1075 | |
1076 | x = SET_SRC (x); | |
1077 | if (GET_CODE (x) == LABEL_REF) | |
4fbe8fa7 | 1078 | return 1; |
7113a566 | 1079 | else |
1080 | return (GET_CODE (x) == IF_THEN_ELSE | |
1081 | && ((GET_CODE (XEXP (x, 2)) == PC | |
1082 | && (GET_CODE (XEXP (x, 1)) == LABEL_REF | |
1083 | || GET_CODE (XEXP (x, 1)) == RETURN)) | |
1084 | || (GET_CODE (XEXP (x, 1)) == PC | |
1085 | && (GET_CODE (XEXP (x, 2)) == LABEL_REF | |
1086 | || GET_CODE (XEXP (x, 2)) == RETURN)))); | |
7014838c | 1087 | |
4fbe8fa7 | 1088 | return 0; |
1089 | } | |
1090 | ||
7014838c | 1091 | /* Return nonzero if INSN is a (possibly) conditional jump inside a |
3a941ad5 | 1092 | PARALLEL. |
7113a566 | 1093 | |
d670e794 | 1094 | Use this function is deprecated, since we need to support combined |
1095 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
4fbe8fa7 | 1096 | |
1097 | int | |
1098 | condjump_in_parallel_p (insn) | |
1099 | rtx insn; | |
1100 | { | |
19cb6b50 | 1101 | rtx x = PATTERN (insn); |
4fbe8fa7 | 1102 | |
1103 | if (GET_CODE (x) != PARALLEL) | |
1104 | return 0; | |
1105 | else | |
1106 | x = XVECEXP (x, 0, 0); | |
1107 | ||
5924de0b | 1108 | if (GET_CODE (x) != SET) |
1109 | return 0; | |
1110 | if (GET_CODE (SET_DEST (x)) != PC) | |
1111 | return 0; | |
1112 | if (GET_CODE (SET_SRC (x)) == LABEL_REF) | |
1113 | return 1; | |
1114 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) | |
1115 | return 0; | |
1116 | if (XEXP (SET_SRC (x), 2) == pc_rtx | |
1117 | && (GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF | |
1118 | || GET_CODE (XEXP (SET_SRC (x), 1)) == RETURN)) | |
1119 | return 1; | |
1120 | if (XEXP (SET_SRC (x), 1) == pc_rtx | |
1121 | && (GET_CODE (XEXP (SET_SRC (x), 2)) == LABEL_REF | |
1122 | || GET_CODE (XEXP (SET_SRC (x), 2)) == RETURN)) | |
1123 | return 1; | |
1124 | return 0; | |
1125 | } | |
1126 | ||
d670e794 | 1127 | /* Return set of PC, otherwise NULL. */ |
1128 | ||
3a941ad5 | 1129 | rtx |
1130 | pc_set (insn) | |
1131 | rtx insn; | |
1132 | { | |
1133 | rtx pat; | |
1134 | if (GET_CODE (insn) != JUMP_INSN) | |
d670e794 | 1135 | return NULL_RTX; |
3a941ad5 | 1136 | pat = PATTERN (insn); |
d670e794 | 1137 | |
1138 | /* The set is allowed to appear either as the insn pattern or | |
1139 | the first set in a PARALLEL. */ | |
1140 | if (GET_CODE (pat) == PARALLEL) | |
1141 | pat = XVECEXP (pat, 0, 0); | |
3a941ad5 | 1142 | if (GET_CODE (pat) == SET && GET_CODE (SET_DEST (pat)) == PC) |
1143 | return pat; | |
d670e794 | 1144 | |
1145 | return NULL_RTX; | |
3a941ad5 | 1146 | } |
1147 | ||
d670e794 | 1148 | /* Return true when insn is an unconditional direct jump, |
1149 | possibly bundled inside a PARALLEL. */ | |
1150 | ||
3a941ad5 | 1151 | int |
1152 | any_uncondjump_p (insn) | |
1153 | rtx insn; | |
1154 | { | |
1155 | rtx x = pc_set (insn); | |
1156 | if (!x) | |
1157 | return 0; | |
1158 | if (GET_CODE (SET_SRC (x)) != LABEL_REF) | |
1159 | return 0; | |
1160 | return 1; | |
1161 | } | |
1162 | ||
d670e794 | 1163 | /* Return true when insn is a conditional jump. This function works for |
3a941ad5 | 1164 | instructions containing PC sets in PARALLELs. The instruction may have |
1165 | various other effects so before removing the jump you must verify | |
9641f63c | 1166 | onlyjump_p. |
3a941ad5 | 1167 | |
d670e794 | 1168 | Note that unlike condjump_p it returns false for unconditional jumps. */ |
1169 | ||
3a941ad5 | 1170 | int |
1171 | any_condjump_p (insn) | |
1172 | rtx insn; | |
1173 | { | |
1174 | rtx x = pc_set (insn); | |
d670e794 | 1175 | enum rtx_code a, b; |
1176 | ||
3a941ad5 | 1177 | if (!x) |
1178 | return 0; | |
d670e794 | 1179 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) |
1180 | return 0; | |
3a941ad5 | 1181 | |
d670e794 | 1182 | a = GET_CODE (XEXP (SET_SRC (x), 1)); |
1183 | b = GET_CODE (XEXP (SET_SRC (x), 2)); | |
3a941ad5 | 1184 | |
d670e794 | 1185 | return ((b == PC && (a == LABEL_REF || a == RETURN)) |
7113a566 | 1186 | || (a == PC && (b == LABEL_REF || b == RETURN))); |
3a941ad5 | 1187 | } |
1188 | ||
8f7b24f3 | 1189 | /* Return the label of a conditional jump. */ |
1190 | ||
1191 | rtx | |
1192 | condjump_label (insn) | |
1193 | rtx insn; | |
1194 | { | |
d670e794 | 1195 | rtx x = pc_set (insn); |
8f7b24f3 | 1196 | |
d670e794 | 1197 | if (!x) |
8f7b24f3 | 1198 | return NULL_RTX; |
1199 | x = SET_SRC (x); | |
1200 | if (GET_CODE (x) == LABEL_REF) | |
1201 | return x; | |
1202 | if (GET_CODE (x) != IF_THEN_ELSE) | |
1203 | return NULL_RTX; | |
1204 | if (XEXP (x, 2) == pc_rtx && GET_CODE (XEXP (x, 1)) == LABEL_REF) | |
1205 | return XEXP (x, 1); | |
1206 | if (XEXP (x, 1) == pc_rtx && GET_CODE (XEXP (x, 2)) == LABEL_REF) | |
1207 | return XEXP (x, 2); | |
1208 | return NULL_RTX; | |
1209 | } | |
1210 | ||
71caadc0 | 1211 | /* Return true if INSN is a (possibly conditional) return insn. */ |
1212 | ||
1213 | static int | |
1214 | returnjump_p_1 (loc, data) | |
1215 | rtx *loc; | |
1216 | void *data ATTRIBUTE_UNUSED; | |
1217 | { | |
1218 | rtx x = *loc; | |
c3987c92 | 1219 | |
1220 | return x && (GET_CODE (x) == RETURN | |
1221 | || (GET_CODE (x) == SET && SET_IS_RETURN_P (x))); | |
71caadc0 | 1222 | } |
1223 | ||
1224 | int | |
1225 | returnjump_p (insn) | |
1226 | rtx insn; | |
1227 | { | |
cbd914e1 | 1228 | if (GET_CODE (insn) != JUMP_INSN) |
1229 | return 0; | |
71caadc0 | 1230 | return for_each_rtx (&PATTERN (insn), returnjump_p_1, NULL); |
1231 | } | |
1232 | ||
459e9193 | 1233 | /* Return true if INSN is a jump that only transfers control and |
1234 | nothing more. */ | |
1235 | ||
1236 | int | |
1237 | onlyjump_p (insn) | |
1238 | rtx insn; | |
1239 | { | |
1240 | rtx set; | |
1241 | ||
1242 | if (GET_CODE (insn) != JUMP_INSN) | |
1243 | return 0; | |
1244 | ||
1245 | set = single_set (insn); | |
1246 | if (set == NULL) | |
1247 | return 0; | |
1248 | if (GET_CODE (SET_DEST (set)) != PC) | |
1249 | return 0; | |
1250 | if (side_effects_p (SET_SRC (set))) | |
1251 | return 0; | |
1252 | ||
1253 | return 1; | |
1254 | } | |
1255 | ||
9bf8c346 | 1256 | #ifdef HAVE_cc0 |
1257 | ||
6ef828f9 | 1258 | /* Return nonzero if X is an RTX that only sets the condition codes |
2dcd83ba | 1259 | and has no side effects. */ |
1260 | ||
1261 | int | |
1262 | only_sets_cc0_p (x) | |
1263 | rtx x; | |
1264 | { | |
1265 | ||
1266 | if (! x) | |
1267 | return 0; | |
1268 | ||
1269 | if (INSN_P (x)) | |
1270 | x = PATTERN (x); | |
1271 | ||
1272 | return sets_cc0_p (x) == 1 && ! side_effects_p (x); | |
1273 | } | |
1274 | ||
5924de0b | 1275 | /* Return 1 if X is an RTX that does nothing but set the condition codes |
1276 | and CLOBBER or USE registers. | |
1277 | Return -1 if X does explicitly set the condition codes, | |
1278 | but also does other things. */ | |
1279 | ||
1280 | int | |
1281 | sets_cc0_p (x) | |
2dcd83ba | 1282 | rtx x; |
5924de0b | 1283 | { |
2dcd83ba | 1284 | |
1285 | if (! x) | |
1286 | return 0; | |
1287 | ||
1288 | if (INSN_P (x)) | |
1289 | x = PATTERN (x); | |
1290 | ||
5924de0b | 1291 | if (GET_CODE (x) == SET && SET_DEST (x) == cc0_rtx) |
1292 | return 1; | |
1293 | if (GET_CODE (x) == PARALLEL) | |
1294 | { | |
1295 | int i; | |
1296 | int sets_cc0 = 0; | |
1297 | int other_things = 0; | |
1298 | for (i = XVECLEN (x, 0) - 1; i >= 0; i--) | |
1299 | { | |
1300 | if (GET_CODE (XVECEXP (x, 0, i)) == SET | |
1301 | && SET_DEST (XVECEXP (x, 0, i)) == cc0_rtx) | |
1302 | sets_cc0 = 1; | |
1303 | else if (GET_CODE (XVECEXP (x, 0, i)) == SET) | |
1304 | other_things = 1; | |
1305 | } | |
1306 | return ! sets_cc0 ? 0 : other_things ? -1 : 1; | |
1307 | } | |
1308 | return 0; | |
5924de0b | 1309 | } |
9bf8c346 | 1310 | #endif |
5924de0b | 1311 | \f |
1312 | /* Follow any unconditional jump at LABEL; | |
1313 | return the ultimate label reached by any such chain of jumps. | |
1314 | If LABEL is not followed by a jump, return LABEL. | |
35e0b416 | 1315 | If the chain loops or we can't find end, return LABEL, |
1316 | since that tells caller to avoid changing the insn. | |
5924de0b | 1317 | |
1318 | If RELOAD_COMPLETED is 0, we do not chain across a NOTE_INSN_LOOP_BEG or | |
1319 | a USE or CLOBBER. */ | |
1320 | ||
1321 | rtx | |
1322 | follow_jumps (label) | |
1323 | rtx label; | |
1324 | { | |
19cb6b50 | 1325 | rtx insn; |
1326 | rtx next; | |
1327 | rtx value = label; | |
1328 | int depth; | |
5924de0b | 1329 | |
1330 | for (depth = 0; | |
1331 | (depth < 10 | |
1332 | && (insn = next_active_insn (value)) != 0 | |
1333 | && GET_CODE (insn) == JUMP_INSN | |
ba08b7e7 | 1334 | && ((JUMP_LABEL (insn) != 0 && any_uncondjump_p (insn) |
1335 | && onlyjump_p (insn)) | |
f93ed41b | 1336 | || GET_CODE (PATTERN (insn)) == RETURN) |
5924de0b | 1337 | && (next = NEXT_INSN (insn)) |
1338 | && GET_CODE (next) == BARRIER); | |
1339 | depth++) | |
1340 | { | |
1341 | /* Don't chain through the insn that jumps into a loop | |
1342 | from outside the loop, | |
1343 | since that would create multiple loop entry jumps | |
1344 | and prevent loop optimization. */ | |
1345 | rtx tem; | |
1346 | if (!reload_completed) | |
1347 | for (tem = value; tem != insn; tem = NEXT_INSN (tem)) | |
1348 | if (GET_CODE (tem) == NOTE | |
55b8f81a | 1349 | && (NOTE_LINE_NUMBER (tem) == NOTE_INSN_LOOP_BEG |
1350 | /* ??? Optional. Disables some optimizations, but makes | |
1351 | gcov output more accurate with -O. */ | |
1352 | || (flag_test_coverage && NOTE_LINE_NUMBER (tem) > 0))) | |
5924de0b | 1353 | return value; |
1354 | ||
1355 | /* If we have found a cycle, make the insn jump to itself. */ | |
1356 | if (JUMP_LABEL (insn) == label) | |
35e0b416 | 1357 | return label; |
cf03b15b | 1358 | |
1359 | tem = next_active_insn (JUMP_LABEL (insn)); | |
1360 | if (tem && (GET_CODE (PATTERN (tem)) == ADDR_VEC | |
1361 | || GET_CODE (PATTERN (tem)) == ADDR_DIFF_VEC)) | |
1362 | break; | |
1363 | ||
5924de0b | 1364 | value = JUMP_LABEL (insn); |
1365 | } | |
35e0b416 | 1366 | if (depth == 10) |
1367 | return label; | |
5924de0b | 1368 | return value; |
1369 | } | |
1370 | ||
5924de0b | 1371 | \f |
1372 | /* Find all CODE_LABELs referred to in X, and increment their use counts. | |
1373 | If INSN is a JUMP_INSN and there is at least one CODE_LABEL referenced | |
1374 | in INSN, then store one of them in JUMP_LABEL (INSN). | |
1375 | If INSN is an INSN or a CALL_INSN and there is at least one CODE_LABEL | |
1376 | referenced in INSN, add a REG_LABEL note containing that label to INSN. | |
1377 | Also, when there are consecutive labels, canonicalize on the last of them. | |
1378 | ||
1379 | Note that two labels separated by a loop-beginning note | |
1380 | must be kept distinct if we have not yet done loop-optimization, | |
1381 | because the gap between them is where loop-optimize | |
1382 | will want to move invariant code to. CROSS_JUMP tells us | |
bf73fcf4 | 1383 | that loop-optimization is done with. */ |
5924de0b | 1384 | |
5377f687 | 1385 | void |
bf73fcf4 | 1386 | mark_jump_label (x, insn, in_mem) |
19cb6b50 | 1387 | rtx x; |
5924de0b | 1388 | rtx insn; |
190099a6 | 1389 | int in_mem; |
5924de0b | 1390 | { |
19cb6b50 | 1391 | RTX_CODE code = GET_CODE (x); |
1392 | int i; | |
1393 | const char *fmt; | |
5924de0b | 1394 | |
1395 | switch (code) | |
1396 | { | |
1397 | case PC: | |
1398 | case CC0: | |
1399 | case REG: | |
1400 | case SUBREG: | |
1401 | case CONST_INT: | |
5924de0b | 1402 | case CONST_DOUBLE: |
1403 | case CLOBBER: | |
1404 | case CALL: | |
1405 | return; | |
1406 | ||
d8e0d332 | 1407 | case MEM: |
190099a6 | 1408 | in_mem = 1; |
1409 | break; | |
1410 | ||
1411 | case SYMBOL_REF: | |
1412 | if (!in_mem) | |
7113a566 | 1413 | return; |
190099a6 | 1414 | |
d8e0d332 | 1415 | /* If this is a constant-pool reference, see if it is a label. */ |
190099a6 | 1416 | if (CONSTANT_POOL_ADDRESS_P (x)) |
bf73fcf4 | 1417 | mark_jump_label (get_pool_constant (x), insn, in_mem); |
d8e0d332 | 1418 | break; |
1419 | ||
5924de0b | 1420 | case LABEL_REF: |
1421 | { | |
b4d3bcce | 1422 | rtx label = XEXP (x, 0); |
b4d3bcce | 1423 | |
74b0991d | 1424 | /* Ignore remaining references to unreachable labels that |
1425 | have been deleted. */ | |
7113a566 | 1426 | if (GET_CODE (label) == NOTE |
74b0991d | 1427 | && NOTE_LINE_NUMBER (label) == NOTE_INSN_DELETED_LABEL) |
1428 | break; | |
1429 | ||
5924de0b | 1430 | if (GET_CODE (label) != CODE_LABEL) |
1431 | abort (); | |
b4d3bcce | 1432 | |
f08cae9d | 1433 | /* Ignore references to labels of containing functions. */ |
1434 | if (LABEL_REF_NONLOCAL_P (x)) | |
1435 | break; | |
b4d3bcce | 1436 | |
5924de0b | 1437 | XEXP (x, 0) = label; |
943e16d8 | 1438 | if (! insn || ! INSN_DELETED_P (insn)) |
1439 | ++LABEL_NUSES (label); | |
b4d3bcce | 1440 | |
5924de0b | 1441 | if (insn) |
1442 | { | |
1443 | if (GET_CODE (insn) == JUMP_INSN) | |
1444 | JUMP_LABEL (insn) = label; | |
ab2237b5 | 1445 | else |
e89849bd | 1446 | { |
ab2237b5 | 1447 | /* Add a REG_LABEL note for LABEL unless there already |
1448 | is one. All uses of a label, except for labels | |
1449 | that are the targets of jumps, must have a | |
1450 | REG_LABEL note. */ | |
1451 | if (! find_reg_note (insn, REG_LABEL, label)) | |
60d9e0ee | 1452 | REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, label, |
ab2237b5 | 1453 | REG_NOTES (insn)); |
5924de0b | 1454 | } |
1455 | } | |
1456 | return; | |
1457 | } | |
1458 | ||
1459 | /* Do walk the labels in a vector, but not the first operand of an | |
1460 | ADDR_DIFF_VEC. Don't set the JUMP_LABEL of a vector. */ | |
1461 | case ADDR_VEC: | |
1462 | case ADDR_DIFF_VEC: | |
943e16d8 | 1463 | if (! INSN_DELETED_P (insn)) |
1464 | { | |
1465 | int eltnum = code == ADDR_DIFF_VEC ? 1 : 0; | |
5924de0b | 1466 | |
943e16d8 | 1467 | for (i = 0; i < XVECLEN (x, eltnum); i++) |
bf73fcf4 | 1468 | mark_jump_label (XVECEXP (x, eltnum, i), NULL_RTX, in_mem); |
943e16d8 | 1469 | } |
0dbd1c74 | 1470 | return; |
7113a566 | 1471 | |
0dbd1c74 | 1472 | default: |
1473 | break; | |
5924de0b | 1474 | } |
1475 | ||
1476 | fmt = GET_RTX_FORMAT (code); | |
1477 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1478 | { | |
1479 | if (fmt[i] == 'e') | |
bf73fcf4 | 1480 | mark_jump_label (XEXP (x, i), insn, in_mem); |
5924de0b | 1481 | else if (fmt[i] == 'E') |
1482 | { | |
19cb6b50 | 1483 | int j; |
5924de0b | 1484 | for (j = 0; j < XVECLEN (x, i); j++) |
bf73fcf4 | 1485 | mark_jump_label (XVECEXP (x, i, j), insn, in_mem); |
5924de0b | 1486 | } |
1487 | } | |
1488 | } | |
1489 | ||
1490 | /* If all INSN does is set the pc, delete it, | |
1491 | and delete the insn that set the condition codes for it | |
1492 | if that's what the previous thing was. */ | |
1493 | ||
1494 | void | |
1495 | delete_jump (insn) | |
1496 | rtx insn; | |
1497 | { | |
19cb6b50 | 1498 | rtx set = single_set (insn); |
f4ef05ab | 1499 | |
1500 | if (set && GET_CODE (SET_DEST (set)) == PC) | |
1501 | delete_computation (insn); | |
1502 | } | |
1503 | ||
155b05dc | 1504 | /* Verify INSN is a BARRIER and delete it. */ |
1505 | ||
1506 | void | |
1507 | delete_barrier (insn) | |
1508 | rtx insn; | |
1509 | { | |
1510 | if (GET_CODE (insn) != BARRIER) | |
1511 | abort (); | |
1512 | ||
1513 | delete_insn (insn); | |
1514 | } | |
1515 | ||
ab1241f2 | 1516 | /* Recursively delete prior insns that compute the value (used only by INSN |
1517 | which the caller is deleting) stored in the register mentioned by NOTE | |
1518 | which is a REG_DEAD note associated with INSN. */ | |
1519 | ||
1520 | static void | |
1521 | delete_prior_computation (note, insn) | |
1522 | rtx note; | |
1523 | rtx insn; | |
1524 | { | |
1525 | rtx our_prev; | |
1526 | rtx reg = XEXP (note, 0); | |
1527 | ||
1528 | for (our_prev = prev_nonnote_insn (insn); | |
272a2170 | 1529 | our_prev && (GET_CODE (our_prev) == INSN |
1530 | || GET_CODE (our_prev) == CALL_INSN); | |
ab1241f2 | 1531 | our_prev = prev_nonnote_insn (our_prev)) |
1532 | { | |
1533 | rtx pat = PATTERN (our_prev); | |
1534 | ||
272a2170 | 1535 | /* If we reach a CALL which is not calling a const function |
1536 | or the callee pops the arguments, then give up. */ | |
1537 | if (GET_CODE (our_prev) == CALL_INSN | |
06a652d1 | 1538 | && (! CONST_OR_PURE_CALL_P (our_prev) |
272a2170 | 1539 | || GET_CODE (pat) != SET || GET_CODE (SET_SRC (pat)) != CALL)) |
1540 | break; | |
1541 | ||
ab1241f2 | 1542 | /* If we reach a SEQUENCE, it is too complex to try to |
31d3e01c | 1543 | do anything with it, so give up. We can be run during |
1544 | and after reorg, so SEQUENCE rtl can legitimately show | |
1545 | up here. */ | |
ab1241f2 | 1546 | if (GET_CODE (pat) == SEQUENCE) |
1547 | break; | |
1548 | ||
1549 | if (GET_CODE (pat) == USE | |
1550 | && GET_CODE (XEXP (pat, 0)) == INSN) | |
1551 | /* reorg creates USEs that look like this. We leave them | |
1552 | alone because reorg needs them for its own purposes. */ | |
1553 | break; | |
1554 | ||
1555 | if (reg_set_p (reg, pat)) | |
1556 | { | |
272a2170 | 1557 | if (side_effects_p (pat) && GET_CODE (our_prev) != CALL_INSN) |
ab1241f2 | 1558 | break; |
1559 | ||
1560 | if (GET_CODE (pat) == PARALLEL) | |
1561 | { | |
1562 | /* If we find a SET of something else, we can't | |
1563 | delete the insn. */ | |
1564 | ||
1565 | int i; | |
1566 | ||
1567 | for (i = 0; i < XVECLEN (pat, 0); i++) | |
1568 | { | |
1569 | rtx part = XVECEXP (pat, 0, i); | |
1570 | ||
1571 | if (GET_CODE (part) == SET | |
1572 | && SET_DEST (part) != reg) | |
1573 | break; | |
1574 | } | |
1575 | ||
1576 | if (i == XVECLEN (pat, 0)) | |
1577 | delete_computation (our_prev); | |
1578 | } | |
1579 | else if (GET_CODE (pat) == SET | |
1580 | && GET_CODE (SET_DEST (pat)) == REG) | |
1581 | { | |
1582 | int dest_regno = REGNO (SET_DEST (pat)); | |
1583 | int dest_endregno | |
7113a566 | 1584 | = (dest_regno |
1585 | + (dest_regno < FIRST_PSEUDO_REGISTER | |
ab1241f2 | 1586 | ? HARD_REGNO_NREGS (dest_regno, |
7113a566 | 1587 | GET_MODE (SET_DEST (pat))) : 1)); |
ab1241f2 | 1588 | int regno = REGNO (reg); |
7113a566 | 1589 | int endregno |
1590 | = (regno | |
1591 | + (regno < FIRST_PSEUDO_REGISTER | |
1592 | ? HARD_REGNO_NREGS (regno, GET_MODE (reg)) : 1)); | |
ab1241f2 | 1593 | |
1594 | if (dest_regno >= regno | |
1595 | && dest_endregno <= endregno) | |
1596 | delete_computation (our_prev); | |
1597 | ||
1598 | /* We may have a multi-word hard register and some, but not | |
1599 | all, of the words of the register are needed in subsequent | |
1600 | insns. Write REG_UNUSED notes for those parts that were not | |
1601 | needed. */ | |
1602 | else if (dest_regno <= regno | |
272a2170 | 1603 | && dest_endregno >= endregno) |
ab1241f2 | 1604 | { |
1605 | int i; | |
1606 | ||
1607 | REG_NOTES (our_prev) | |
7113a566 | 1608 | = gen_rtx_EXPR_LIST (REG_UNUSED, reg, |
1609 | REG_NOTES (our_prev)); | |
ab1241f2 | 1610 | |
1611 | for (i = dest_regno; i < dest_endregno; i++) | |
1612 | if (! find_regno_note (our_prev, REG_UNUSED, i)) | |
1613 | break; | |
1614 | ||
1615 | if (i == dest_endregno) | |
1616 | delete_computation (our_prev); | |
1617 | } | |
1618 | } | |
1619 | ||
1620 | break; | |
1621 | } | |
1622 | ||
1623 | /* If PAT references the register that dies here, it is an | |
1624 | additional use. Hence any prior SET isn't dead. However, this | |
1625 | insn becomes the new place for the REG_DEAD note. */ | |
1626 | if (reg_overlap_mentioned_p (reg, pat)) | |
1627 | { | |
1628 | XEXP (note, 1) = REG_NOTES (our_prev); | |
1629 | REG_NOTES (our_prev) = note; | |
1630 | break; | |
1631 | } | |
1632 | } | |
1633 | } | |
1634 | ||
f4ef05ab | 1635 | /* Delete INSN and recursively delete insns that compute values used only |
1636 | by INSN. This uses the REG_DEAD notes computed during flow analysis. | |
1637 | If we are running before flow.c, we need do nothing since flow.c will | |
1638 | delete dead code. We also can't know if the registers being used are | |
1639 | dead or not at this point. | |
1640 | ||
1641 | Otherwise, look at all our REG_DEAD notes. If a previous insn does | |
1642 | nothing other than set a register that dies in this insn, we can delete | |
1643 | that insn as well. | |
1644 | ||
1645 | On machines with CC0, if CC0 is used in this insn, we may be able to | |
1646 | delete the insn that set it. */ | |
1647 | ||
fb374064 | 1648 | static void |
f4ef05ab | 1649 | delete_computation (insn) |
1650 | rtx insn; | |
1651 | { | |
1652 | rtx note, next; | |
5924de0b | 1653 | |
5924de0b | 1654 | #ifdef HAVE_cc0 |
41d75671 | 1655 | if (reg_referenced_p (cc0_rtx, PATTERN (insn))) |
f4ef05ab | 1656 | { |
5b39732e | 1657 | rtx prev = prev_nonnote_insn (insn); |
5924de0b | 1658 | /* We assume that at this stage |
1659 | CC's are always set explicitly | |
1660 | and always immediately before the jump that | |
1661 | will use them. So if the previous insn | |
1662 | exists to set the CC's, delete it | |
1663 | (unless it performs auto-increments, etc.). */ | |
1664 | if (prev && GET_CODE (prev) == INSN | |
1665 | && sets_cc0_p (PATTERN (prev))) | |
1666 | { | |
1667 | if (sets_cc0_p (PATTERN (prev)) > 0 | |
ab1241f2 | 1668 | && ! side_effects_p (PATTERN (prev))) |
f4ef05ab | 1669 | delete_computation (prev); |
5924de0b | 1670 | else |
1671 | /* Otherwise, show that cc0 won't be used. */ | |
941522d6 | 1672 | REG_NOTES (prev) = gen_rtx_EXPR_LIST (REG_UNUSED, |
1673 | cc0_rtx, REG_NOTES (prev)); | |
5924de0b | 1674 | } |
5b39732e | 1675 | } |
f4ef05ab | 1676 | #endif |
5924de0b | 1677 | |
5b39732e | 1678 | for (note = REG_NOTES (insn); note; note = next) |
1679 | { | |
5b39732e | 1680 | next = XEXP (note, 1); |
5924de0b | 1681 | |
5b39732e | 1682 | if (REG_NOTE_KIND (note) != REG_DEAD |
1683 | /* Verify that the REG_NOTE is legitimate. */ | |
1684 | || GET_CODE (XEXP (note, 0)) != REG) | |
1685 | continue; | |
5924de0b | 1686 | |
ab1241f2 | 1687 | delete_prior_computation (note, insn); |
5924de0b | 1688 | } |
f4ef05ab | 1689 | |
e4bf866d | 1690 | delete_related_insns (insn); |
5924de0b | 1691 | } |
1692 | \f | |
e4bf866d | 1693 | /* Delete insn INSN from the chain of insns and update label ref counts |
1694 | and delete insns now unreachable. | |
1695 | ||
1696 | Returns the first insn after INSN that was not deleted. | |
5924de0b | 1697 | |
e4bf866d | 1698 | Usage of this instruction is deprecated. Use delete_insn instead and |
1699 | subsequent cfg_cleanup pass to delete unreachable code if needed. */ | |
5924de0b | 1700 | |
1701 | rtx | |
e4bf866d | 1702 | delete_related_insns (insn) |
19cb6b50 | 1703 | rtx insn; |
5924de0b | 1704 | { |
19cb6b50 | 1705 | int was_code_label = (GET_CODE (insn) == CODE_LABEL); |
d3df77e9 | 1706 | rtx note; |
e4bf866d | 1707 | rtx next = NEXT_INSN (insn), prev = PREV_INSN (insn); |
5924de0b | 1708 | |
1709 | while (next && INSN_DELETED_P (next)) | |
1710 | next = NEXT_INSN (next); | |
1711 | ||
1712 | /* This insn is already deleted => return first following nondeleted. */ | |
1713 | if (INSN_DELETED_P (insn)) | |
1714 | return next; | |
1715 | ||
e4bf866d | 1716 | delete_insn (insn); |
5924de0b | 1717 | |
5924de0b | 1718 | /* If instruction is followed by a barrier, |
1719 | delete the barrier too. */ | |
1720 | ||
1721 | if (next != 0 && GET_CODE (next) == BARRIER) | |
e4bf866d | 1722 | delete_insn (next); |
5924de0b | 1723 | |
1724 | /* If deleting a jump, decrement the count of the label, | |
1725 | and delete the label if it is now unused. */ | |
1726 | ||
1727 | if (GET_CODE (insn) == JUMP_INSN && JUMP_LABEL (insn)) | |
1793cd6b | 1728 | { |
1729 | rtx lab = JUMP_LABEL (insn), lab_next; | |
1730 | ||
e4bf866d | 1731 | if (LABEL_NUSES (lab) == 0) |
1793cd6b | 1732 | { |
1733 | /* This can delete NEXT or PREV, | |
1734 | either directly if NEXT is JUMP_LABEL (INSN), | |
1735 | or indirectly through more levels of jumps. */ | |
e4bf866d | 1736 | delete_related_insns (lab); |
1793cd6b | 1737 | |
1738 | /* I feel a little doubtful about this loop, | |
1739 | but I see no clean and sure alternative way | |
1740 | to find the first insn after INSN that is not now deleted. | |
1741 | I hope this works. */ | |
1742 | while (next && INSN_DELETED_P (next)) | |
1743 | next = NEXT_INSN (next); | |
1744 | return next; | |
1745 | } | |
1746 | else if ((lab_next = next_nonnote_insn (lab)) != NULL | |
1747 | && GET_CODE (lab_next) == JUMP_INSN | |
1748 | && (GET_CODE (PATTERN (lab_next)) == ADDR_VEC | |
1749 | || GET_CODE (PATTERN (lab_next)) == ADDR_DIFF_VEC)) | |
1750 | { | |
1751 | /* If we're deleting the tablejump, delete the dispatch table. | |
4a82352a | 1752 | We may not be able to kill the label immediately preceding |
1793cd6b | 1753 | just yet, as it might be referenced in code leading up to |
1754 | the tablejump. */ | |
e4bf866d | 1755 | delete_related_insns (lab_next); |
1793cd6b | 1756 | } |
1757 | } | |
5924de0b | 1758 | |
9c9e0c01 | 1759 | /* Likewise if we're deleting a dispatch table. */ |
1760 | ||
1761 | if (GET_CODE (insn) == JUMP_INSN | |
1762 | && (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
1763 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)) | |
1764 | { | |
1765 | rtx pat = PATTERN (insn); | |
1766 | int i, diff_vec_p = GET_CODE (pat) == ADDR_DIFF_VEC; | |
1767 | int len = XVECLEN (pat, diff_vec_p); | |
1768 | ||
1769 | for (i = 0; i < len; i++) | |
e4bf866d | 1770 | if (LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0)) == 0) |
1771 | delete_related_insns (XEXP (XVECEXP (pat, diff_vec_p, i), 0)); | |
9c9e0c01 | 1772 | while (next && INSN_DELETED_P (next)) |
1773 | next = NEXT_INSN (next); | |
1774 | return next; | |
1775 | } | |
1776 | ||
d3df77e9 | 1777 | /* Likewise for an ordinary INSN / CALL_INSN with a REG_LABEL note. */ |
1778 | if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
1779 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) | |
0c97f529 | 1780 | if (REG_NOTE_KIND (note) == REG_LABEL |
1781 | /* This could also be a NOTE_INSN_DELETED_LABEL note. */ | |
1782 | && GET_CODE (XEXP (note, 0)) == CODE_LABEL) | |
e4bf866d | 1783 | if (LABEL_NUSES (XEXP (note, 0)) == 0) |
1784 | delete_related_insns (XEXP (note, 0)); | |
d3df77e9 | 1785 | |
5924de0b | 1786 | while (prev && (INSN_DELETED_P (prev) || GET_CODE (prev) == NOTE)) |
1787 | prev = PREV_INSN (prev); | |
1788 | ||
1789 | /* If INSN was a label and a dispatch table follows it, | |
1790 | delete the dispatch table. The tablejump must have gone already. | |
1791 | It isn't useful to fall through into a table. */ | |
1792 | ||
9cdc08c6 | 1793 | if (was_code_label |
5924de0b | 1794 | && NEXT_INSN (insn) != 0 |
1795 | && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN | |
1796 | && (GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_VEC | |
1797 | || GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_DIFF_VEC)) | |
e4bf866d | 1798 | next = delete_related_insns (NEXT_INSN (insn)); |
5924de0b | 1799 | |
1800 | /* If INSN was a label, delete insns following it if now unreachable. */ | |
1801 | ||
9cdc08c6 | 1802 | if (was_code_label && prev && GET_CODE (prev) == BARRIER) |
5924de0b | 1803 | { |
19cb6b50 | 1804 | RTX_CODE code; |
5924de0b | 1805 | while (next != 0 |
fb374064 | 1806 | && (GET_RTX_CLASS (code = GET_CODE (next)) == 'i' |
64f0b11f | 1807 | || code == NOTE || code == BARRIER |
59bee35e | 1808 | || (code == CODE_LABEL && INSN_DELETED_P (next)))) |
5924de0b | 1809 | { |
1810 | if (code == NOTE | |
1811 | && NOTE_LINE_NUMBER (next) != NOTE_INSN_FUNCTION_END) | |
1812 | next = NEXT_INSN (next); | |
59bee35e | 1813 | /* Keep going past other deleted labels to delete what follows. */ |
1814 | else if (code == CODE_LABEL && INSN_DELETED_P (next)) | |
1815 | next = NEXT_INSN (next); | |
5924de0b | 1816 | else |
1817 | /* Note: if this deletes a jump, it can cause more | |
1818 | deletion of unreachable code, after a different label. | |
1819 | As long as the value from this recursive call is correct, | |
1820 | this invocation functions correctly. */ | |
e4bf866d | 1821 | next = delete_related_insns (next); |
5924de0b | 1822 | } |
1823 | } | |
1824 | ||
1825 | return next; | |
1826 | } | |
1827 | ||
1828 | /* Advance from INSN till reaching something not deleted | |
1829 | then return that. May return INSN itself. */ | |
1830 | ||
1831 | rtx | |
1832 | next_nondeleted_insn (insn) | |
1833 | rtx insn; | |
1834 | { | |
1835 | while (INSN_DELETED_P (insn)) | |
1836 | insn = NEXT_INSN (insn); | |
1837 | return insn; | |
1838 | } | |
1839 | \f | |
1840 | /* Delete a range of insns from FROM to TO, inclusive. | |
1841 | This is for the sake of peephole optimization, so assume | |
1842 | that whatever these insns do will still be done by a new | |
1843 | peephole insn that will replace them. */ | |
1844 | ||
1845 | void | |
1846 | delete_for_peephole (from, to) | |
19cb6b50 | 1847 | rtx from, to; |
5924de0b | 1848 | { |
19cb6b50 | 1849 | rtx insn = from; |
5924de0b | 1850 | |
1851 | while (1) | |
1852 | { | |
19cb6b50 | 1853 | rtx next = NEXT_INSN (insn); |
1854 | rtx prev = PREV_INSN (insn); | |
5924de0b | 1855 | |
1856 | if (GET_CODE (insn) != NOTE) | |
1857 | { | |
1858 | INSN_DELETED_P (insn) = 1; | |
1859 | ||
1860 | /* Patch this insn out of the chain. */ | |
1861 | /* We don't do this all at once, because we | |
1862 | must preserve all NOTEs. */ | |
1863 | if (prev) | |
1864 | NEXT_INSN (prev) = next; | |
1865 | ||
1866 | if (next) | |
1867 | PREV_INSN (next) = prev; | |
1868 | } | |
1869 | ||
1870 | if (insn == to) | |
1871 | break; | |
1872 | insn = next; | |
1873 | } | |
1874 | ||
1875 | /* Note that if TO is an unconditional jump | |
1876 | we *do not* delete the BARRIER that follows, | |
1877 | since the peephole that replaces this sequence | |
1878 | is also an unconditional jump in that case. */ | |
1879 | } | |
1880 | \f | |
71a3455a | 1881 | /* We have determined that INSN is never reached, and are about to |
1882 | delete it. Print a warning if the user asked for one. | |
1883 | ||
1884 | To try to make this warning more useful, this should only be called | |
1885 | once per basic block not reached, and it only warns when the basic | |
1886 | block contains more than one line from the current function, and | |
1887 | contains at least one operation. CSE and inlining can duplicate insns, | |
1888 | so it's possible to get spurious warnings from this. */ | |
1889 | ||
1890 | void | |
5b154f04 | 1891 | never_reached_warning (avoided_insn, finish) |
1892 | rtx avoided_insn, finish; | |
71a3455a | 1893 | { |
1894 | rtx insn; | |
1895 | rtx a_line_note = NULL; | |
5b154f04 | 1896 | int two_avoided_lines = 0, contains_insn = 0, reached_end = 0; |
7113a566 | 1897 | |
71a3455a | 1898 | if (! warn_notreached) |
1899 | return; | |
1900 | ||
1901 | /* Scan forwards, looking at LINE_NUMBER notes, until | |
1902 | we hit a LABEL or we run out of insns. */ | |
7113a566 | 1903 | |
71a3455a | 1904 | for (insn = avoided_insn; insn != NULL; insn = NEXT_INSN (insn)) |
1905 | { | |
5b154f04 | 1906 | if (finish == NULL && GET_CODE (insn) == CODE_LABEL) |
7113a566 | 1907 | break; |
5b154f04 | 1908 | |
1909 | if (GET_CODE (insn) == NOTE /* A line number note? */ | |
1910 | && NOTE_LINE_NUMBER (insn) >= 0) | |
71a3455a | 1911 | { |
1912 | if (a_line_note == NULL) | |
1913 | a_line_note = insn; | |
1914 | else | |
1915 | two_avoided_lines |= (NOTE_LINE_NUMBER (a_line_note) | |
1916 | != NOTE_LINE_NUMBER (insn)); | |
1917 | } | |
9204e736 | 1918 | else if (INSN_P (insn)) |
5b154f04 | 1919 | { |
1920 | if (reached_end) | |
1921 | break; | |
1922 | contains_insn = 1; | |
1923 | } | |
1924 | ||
1925 | if (insn == finish) | |
1926 | reached_end = 1; | |
71a3455a | 1927 | } |
1928 | if (two_avoided_lines && contains_insn) | |
1929 | warning_with_file_and_line (NOTE_SOURCE_FILE (a_line_note), | |
1930 | NOTE_LINE_NUMBER (a_line_note), | |
1931 | "will never be executed"); | |
1932 | } | |
1933 | \f | |
a8b5d014 | 1934 | /* Throughout LOC, redirect OLABEL to NLABEL. Treat null OLABEL or |
1935 | NLABEL as a return. Accrue modifications into the change group. */ | |
5924de0b | 1936 | |
a8b5d014 | 1937 | static void |
1938 | redirect_exp_1 (loc, olabel, nlabel, insn) | |
1939 | rtx *loc; | |
1940 | rtx olabel, nlabel; | |
5924de0b | 1941 | rtx insn; |
1942 | { | |
19cb6b50 | 1943 | rtx x = *loc; |
1944 | RTX_CODE code = GET_CODE (x); | |
1945 | int i; | |
1946 | const char *fmt; | |
5924de0b | 1947 | |
a8b5d014 | 1948 | if (code == LABEL_REF) |
5924de0b | 1949 | { |
a8b5d014 | 1950 | if (XEXP (x, 0) == olabel) |
1951 | { | |
1952 | rtx n; | |
1953 | if (nlabel) | |
1954 | n = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1955 | else | |
7113a566 | 1956 | n = gen_rtx_RETURN (VOIDmode); |
5924de0b | 1957 | |
a8b5d014 | 1958 | validate_change (insn, loc, n, 1); |
1959 | return; | |
1960 | } | |
1961 | } | |
1962 | else if (code == RETURN && olabel == 0) | |
1963 | { | |
1964 | x = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1965 | if (loc == &PATTERN (insn)) | |
1966 | x = gen_rtx_SET (VOIDmode, pc_rtx, x); | |
1967 | validate_change (insn, loc, x, 1); | |
1968 | return; | |
1969 | } | |
5924de0b | 1970 | |
a8b5d014 | 1971 | if (code == SET && nlabel == 0 && SET_DEST (x) == pc_rtx |
1972 | && GET_CODE (SET_SRC (x)) == LABEL_REF | |
1973 | && XEXP (SET_SRC (x), 0) == olabel) | |
1974 | { | |
1975 | validate_change (insn, loc, gen_rtx_RETURN (VOIDmode), 1); | |
1976 | return; | |
5924de0b | 1977 | } |
1978 | ||
1979 | fmt = GET_RTX_FORMAT (code); | |
1980 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1981 | { | |
1982 | if (fmt[i] == 'e') | |
a8b5d014 | 1983 | redirect_exp_1 (&XEXP (x, i), olabel, nlabel, insn); |
1bd8ca86 | 1984 | else if (fmt[i] == 'E') |
5924de0b | 1985 | { |
19cb6b50 | 1986 | int j; |
5924de0b | 1987 | for (j = 0; j < XVECLEN (x, i); j++) |
a8b5d014 | 1988 | redirect_exp_1 (&XVECEXP (x, i, j), olabel, nlabel, insn); |
5924de0b | 1989 | } |
1990 | } | |
a8b5d014 | 1991 | } |
5924de0b | 1992 | |
a8b5d014 | 1993 | /* Similar, but apply the change group and report success or failure. */ |
1994 | ||
ba08b7e7 | 1995 | static int |
1996 | redirect_exp (olabel, nlabel, insn) | |
a8b5d014 | 1997 | rtx olabel, nlabel; |
1998 | rtx insn; | |
1999 | { | |
ba08b7e7 | 2000 | rtx *loc; |
2001 | ||
2002 | if (GET_CODE (PATTERN (insn)) == PARALLEL) | |
2003 | loc = &XVECEXP (PATTERN (insn), 0, 0); | |
2004 | else | |
2005 | loc = &PATTERN (insn); | |
2006 | ||
a8b5d014 | 2007 | redirect_exp_1 (loc, olabel, nlabel, insn); |
2008 | if (num_validated_changes () == 0) | |
2009 | return 0; | |
2010 | ||
2011 | return apply_change_group (); | |
5924de0b | 2012 | } |
a8b5d014 | 2013 | |
2014 | /* Make JUMP go to NLABEL instead of where it jumps now. Accrue | |
2015 | the modifications into the change group. Return false if we did | |
2016 | not see how to do that. */ | |
2017 | ||
2018 | int | |
2019 | redirect_jump_1 (jump, nlabel) | |
2020 | rtx jump, nlabel; | |
2021 | { | |
2022 | int ochanges = num_validated_changes (); | |
ba08b7e7 | 2023 | rtx *loc; |
2024 | ||
2025 | if (GET_CODE (PATTERN (jump)) == PARALLEL) | |
2026 | loc = &XVECEXP (PATTERN (jump), 0, 0); | |
2027 | else | |
2028 | loc = &PATTERN (jump); | |
2029 | ||
2030 | redirect_exp_1 (loc, JUMP_LABEL (jump), nlabel, jump); | |
a8b5d014 | 2031 | return num_validated_changes () > ochanges; |
2032 | } | |
2033 | ||
2034 | /* Make JUMP go to NLABEL instead of where it jumps now. If the old | |
2035 | jump target label is unused as a result, it and the code following | |
2036 | it may be deleted. | |
5924de0b | 2037 | |
2038 | If NLABEL is zero, we are to turn the jump into a (possibly conditional) | |
2039 | RETURN insn. | |
2040 | ||
a8b5d014 | 2041 | The return value will be 1 if the change was made, 0 if it wasn't |
2042 | (this can only occur for NLABEL == 0). */ | |
5924de0b | 2043 | |
2044 | int | |
f8cacb57 | 2045 | redirect_jump (jump, nlabel, delete_unused) |
5924de0b | 2046 | rtx jump, nlabel; |
f8cacb57 | 2047 | int delete_unused; |
5924de0b | 2048 | { |
19cb6b50 | 2049 | rtx olabel = JUMP_LABEL (jump); |
5924de0b | 2050 | |
2051 | if (nlabel == olabel) | |
2052 | return 1; | |
2053 | ||
ba08b7e7 | 2054 | if (! redirect_exp (olabel, nlabel, jump)) |
5924de0b | 2055 | return 0; |
2056 | ||
5924de0b | 2057 | JUMP_LABEL (jump) = nlabel; |
2058 | if (nlabel) | |
2059 | ++LABEL_NUSES (nlabel); | |
2060 | ||
9cf49039 | 2061 | /* If we're eliding the jump over exception cleanups at the end of a |
2062 | function, move the function end note so that -Wreturn-type works. */ | |
4476207f | 2063 | if (olabel && nlabel |
2064 | && NEXT_INSN (olabel) | |
9cf49039 | 2065 | && GET_CODE (NEXT_INSN (olabel)) == NOTE |
2066 | && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END) | |
2067 | emit_note_after (NOTE_INSN_FUNCTION_END, nlabel); | |
2068 | ||
7f8c3466 | 2069 | if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused |
2070 | /* Undefined labels will remain outside the insn stream. */ | |
2071 | && INSN_UID (olabel)) | |
e4bf866d | 2072 | delete_related_insns (olabel); |
5924de0b | 2073 | |
2074 | return 1; | |
2075 | } | |
2076 | ||
7113a566 | 2077 | /* Invert the jump condition of rtx X contained in jump insn, INSN. |
a8b5d014 | 2078 | Accrue the modifications into the change group. */ |
2079 | ||
2080 | static void | |
ba08b7e7 | 2081 | invert_exp_1 (insn) |
a8b5d014 | 2082 | rtx insn; |
2083 | { | |
19cb6b50 | 2084 | RTX_CODE code; |
ba08b7e7 | 2085 | rtx x = pc_set (insn); |
2086 | ||
2087 | if (!x) | |
7113a566 | 2088 | abort (); |
ba08b7e7 | 2089 | x = SET_SRC (x); |
a8b5d014 | 2090 | |
2091 | code = GET_CODE (x); | |
2092 | ||
2093 | if (code == IF_THEN_ELSE) | |
2094 | { | |
19cb6b50 | 2095 | rtx comp = XEXP (x, 0); |
2096 | rtx tem; | |
7da6ea0c | 2097 | enum rtx_code reversed_code; |
a8b5d014 | 2098 | |
2099 | /* We can do this in two ways: The preferable way, which can only | |
2100 | be done if this is not an integer comparison, is to reverse | |
2101 | the comparison code. Otherwise, swap the THEN-part and ELSE-part | |
2102 | of the IF_THEN_ELSE. If we can't do either, fail. */ | |
2103 | ||
7da6ea0c | 2104 | reversed_code = reversed_comparison_code (comp, insn); |
2105 | ||
2106 | if (reversed_code != UNKNOWN) | |
a8b5d014 | 2107 | { |
2108 | validate_change (insn, &XEXP (x, 0), | |
7da6ea0c | 2109 | gen_rtx_fmt_ee (reversed_code, |
a8b5d014 | 2110 | GET_MODE (comp), XEXP (comp, 0), |
2111 | XEXP (comp, 1)), | |
2112 | 1); | |
2113 | return; | |
2114 | } | |
7113a566 | 2115 | |
a8b5d014 | 2116 | tem = XEXP (x, 1); |
2117 | validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1); | |
2118 | validate_change (insn, &XEXP (x, 2), tem, 1); | |
a8b5d014 | 2119 | } |
ba08b7e7 | 2120 | else |
2121 | abort (); | |
a8b5d014 | 2122 | } |
2123 | ||
7113a566 | 2124 | /* Invert the jump condition of conditional jump insn, INSN. |
a8b5d014 | 2125 | |
2126 | Return 1 if we can do so, 0 if we cannot find a way to do so that | |
2127 | matches a pattern. */ | |
2128 | ||
ba08b7e7 | 2129 | static int |
2130 | invert_exp (insn) | |
a8b5d014 | 2131 | rtx insn; |
2132 | { | |
ba08b7e7 | 2133 | invert_exp_1 (insn); |
a8b5d014 | 2134 | if (num_validated_changes () == 0) |
2135 | return 0; | |
2136 | ||
2137 | return apply_change_group (); | |
2138 | } | |
2139 | ||
2140 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2141 | NLABEL instead of where it jumps now. Accrue changes into the | |
2142 | change group. Return false if we didn't see how to perform the | |
2143 | inversion and redirection. */ | |
2144 | ||
2145 | int | |
2146 | invert_jump_1 (jump, nlabel) | |
2147 | rtx jump, nlabel; | |
2148 | { | |
2149 | int ochanges; | |
2150 | ||
2151 | ochanges = num_validated_changes (); | |
ba08b7e7 | 2152 | invert_exp_1 (jump); |
a8b5d014 | 2153 | if (num_validated_changes () == ochanges) |
2154 | return 0; | |
2155 | ||
2156 | return redirect_jump_1 (jump, nlabel); | |
2157 | } | |
2158 | ||
2159 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2160 | NLABEL instead of where it jumps now. Return true if successful. */ | |
2161 | ||
2162 | int | |
f8cacb57 | 2163 | invert_jump (jump, nlabel, delete_unused) |
a8b5d014 | 2164 | rtx jump, nlabel; |
f8cacb57 | 2165 | int delete_unused; |
a8b5d014 | 2166 | { |
2167 | /* We have to either invert the condition and change the label or | |
2168 | do neither. Either operation could fail. We first try to invert | |
2169 | the jump. If that succeeds, we try changing the label. If that fails, | |
2170 | we invert the jump back to what it was. */ | |
2171 | ||
ba08b7e7 | 2172 | if (! invert_exp (jump)) |
a8b5d014 | 2173 | return 0; |
2174 | ||
f8cacb57 | 2175 | if (redirect_jump (jump, nlabel, delete_unused)) |
a8b5d014 | 2176 | { |
13488c51 | 2177 | invert_br_probabilities (jump); |
a8b5d014 | 2178 | |
2179 | return 1; | |
2180 | } | |
2181 | ||
ba08b7e7 | 2182 | if (! invert_exp (jump)) |
a8b5d014 | 2183 | /* This should just be putting it back the way it was. */ |
2184 | abort (); | |
2185 | ||
2186 | return 0; | |
2187 | } | |
2188 | ||
5924de0b | 2189 | \f |
2190 | /* Like rtx_equal_p except that it considers two REGs as equal | |
6c60c295 | 2191 | if they renumber to the same value and considers two commutative |
2192 | operations to be the same if the order of the operands has been | |
2207ad6a | 2193 | reversed. |
2194 | ||
2195 | ??? Addition is not commutative on the PA due to the weird implicit | |
2196 | space register selection rules for memory addresses. Therefore, we | |
2197 | don't consider a + b == b + a. | |
2198 | ||
2199 | We could/should make this test a little tighter. Possibly only | |
2200 | disabling it on the PA via some backend macro or only disabling this | |
2201 | case when the PLUS is inside a MEM. */ | |
5924de0b | 2202 | |
2203 | int | |
2204 | rtx_renumbered_equal_p (x, y) | |
2205 | rtx x, y; | |
2206 | { | |
19cb6b50 | 2207 | int i; |
2208 | RTX_CODE code = GET_CODE (x); | |
2209 | const char *fmt; | |
7113a566 | 2210 | |
5924de0b | 2211 | if (x == y) |
2212 | return 1; | |
6c60c295 | 2213 | |
5924de0b | 2214 | if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)) |
2215 | && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG | |
2216 | && GET_CODE (SUBREG_REG (y)) == REG))) | |
2217 | { | |
6c60c295 | 2218 | int reg_x = -1, reg_y = -1; |
701e46d0 | 2219 | int byte_x = 0, byte_y = 0; |
5924de0b | 2220 | |
2221 | if (GET_MODE (x) != GET_MODE (y)) | |
2222 | return 0; | |
2223 | ||
2224 | /* If we haven't done any renumbering, don't | |
2225 | make any assumptions. */ | |
2226 | if (reg_renumber == 0) | |
2227 | return rtx_equal_p (x, y); | |
2228 | ||
2229 | if (code == SUBREG) | |
2230 | { | |
6c60c295 | 2231 | reg_x = REGNO (SUBREG_REG (x)); |
701e46d0 | 2232 | byte_x = SUBREG_BYTE (x); |
6c60c295 | 2233 | |
2234 | if (reg_renumber[reg_x] >= 0) | |
2235 | { | |
701e46d0 | 2236 | reg_x = subreg_regno_offset (reg_renumber[reg_x], |
2237 | GET_MODE (SUBREG_REG (x)), | |
2238 | byte_x, | |
2239 | GET_MODE (x)); | |
2240 | byte_x = 0; | |
6c60c295 | 2241 | } |
5924de0b | 2242 | } |
2243 | else | |
2244 | { | |
6c60c295 | 2245 | reg_x = REGNO (x); |
2246 | if (reg_renumber[reg_x] >= 0) | |
2247 | reg_x = reg_renumber[reg_x]; | |
5924de0b | 2248 | } |
6c60c295 | 2249 | |
5924de0b | 2250 | if (GET_CODE (y) == SUBREG) |
2251 | { | |
6c60c295 | 2252 | reg_y = REGNO (SUBREG_REG (y)); |
701e46d0 | 2253 | byte_y = SUBREG_BYTE (y); |
6c60c295 | 2254 | |
2255 | if (reg_renumber[reg_y] >= 0) | |
2256 | { | |
701e46d0 | 2257 | reg_y = subreg_regno_offset (reg_renumber[reg_y], |
2258 | GET_MODE (SUBREG_REG (y)), | |
2259 | byte_y, | |
2260 | GET_MODE (y)); | |
2261 | byte_y = 0; | |
6c60c295 | 2262 | } |
5924de0b | 2263 | } |
2264 | else | |
2265 | { | |
6c60c295 | 2266 | reg_y = REGNO (y); |
2267 | if (reg_renumber[reg_y] >= 0) | |
2268 | reg_y = reg_renumber[reg_y]; | |
5924de0b | 2269 | } |
6c60c295 | 2270 | |
701e46d0 | 2271 | return reg_x >= 0 && reg_x == reg_y && byte_x == byte_y; |
5924de0b | 2272 | } |
6c60c295 | 2273 | |
7113a566 | 2274 | /* Now we have disposed of all the cases |
5924de0b | 2275 | in which different rtx codes can match. */ |
2276 | if (code != GET_CODE (y)) | |
2277 | return 0; | |
6c60c295 | 2278 | |
5924de0b | 2279 | switch (code) |
2280 | { | |
2281 | case PC: | |
2282 | case CC0: | |
2283 | case ADDR_VEC: | |
2284 | case ADDR_DIFF_VEC: | |
2285 | return 0; | |
2286 | ||
2287 | case CONST_INT: | |
5fbd420b | 2288 | return INTVAL (x) == INTVAL (y); |
5924de0b | 2289 | |
2290 | case LABEL_REF: | |
f08cae9d | 2291 | /* We can't assume nonlocal labels have their following insns yet. */ |
2292 | if (LABEL_REF_NONLOCAL_P (x) || LABEL_REF_NONLOCAL_P (y)) | |
2293 | return XEXP (x, 0) == XEXP (y, 0); | |
6c60c295 | 2294 | |
5924de0b | 2295 | /* Two label-refs are equivalent if they point at labels |
2296 | in the same position in the instruction stream. */ | |
2297 | return (next_real_insn (XEXP (x, 0)) | |
2298 | == next_real_insn (XEXP (y, 0))); | |
2299 | ||
2300 | case SYMBOL_REF: | |
2301 | return XSTR (x, 0) == XSTR (y, 0); | |
0dbd1c74 | 2302 | |
fc41ccae | 2303 | case CODE_LABEL: |
2304 | /* If we didn't match EQ equality above, they aren't the same. */ | |
2305 | return 0; | |
2306 | ||
0dbd1c74 | 2307 | default: |
2308 | break; | |
5924de0b | 2309 | } |
2310 | ||
2311 | /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ | |
2312 | ||
2313 | if (GET_MODE (x) != GET_MODE (y)) | |
2314 | return 0; | |
2315 | ||
6c60c295 | 2316 | /* For commutative operations, the RTX match if the operand match in any |
2207ad6a | 2317 | order. Also handle the simple binary and unary cases without a loop. |
2318 | ||
2319 | ??? Don't consider PLUS a commutative operator; see comments above. */ | |
2320 | if ((code == EQ || code == NE || GET_RTX_CLASS (code) == 'c') | |
2321 | && code != PLUS) | |
6c60c295 | 2322 | return ((rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) |
2323 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))) | |
2324 | || (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 1)) | |
2325 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 0)))); | |
2326 | else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2') | |
2327 | return (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) | |
2328 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))); | |
2329 | else if (GET_RTX_CLASS (code) == '1') | |
2330 | return rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)); | |
2331 | ||
5924de0b | 2332 | /* Compare the elements. If any pair of corresponding elements |
2333 | fail to match, return 0 for the whole things. */ | |
2334 | ||
2335 | fmt = GET_RTX_FORMAT (code); | |
2336 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
2337 | { | |
19cb6b50 | 2338 | int j; |
5924de0b | 2339 | switch (fmt[i]) |
2340 | { | |
1bb04728 | 2341 | case 'w': |
2342 | if (XWINT (x, i) != XWINT (y, i)) | |
2343 | return 0; | |
2344 | break; | |
2345 | ||
5924de0b | 2346 | case 'i': |
2347 | if (XINT (x, i) != XINT (y, i)) | |
2348 | return 0; | |
2349 | break; | |
2350 | ||
a0d79d69 | 2351 | case 't': |
2352 | if (XTREE (x, i) != XTREE (y, i)) | |
2353 | return 0; | |
2354 | break; | |
2355 | ||
5924de0b | 2356 | case 's': |
2357 | if (strcmp (XSTR (x, i), XSTR (y, i))) | |
2358 | return 0; | |
2359 | break; | |
2360 | ||
2361 | case 'e': | |
2362 | if (! rtx_renumbered_equal_p (XEXP (x, i), XEXP (y, i))) | |
2363 | return 0; | |
2364 | break; | |
2365 | ||
2366 | case 'u': | |
2367 | if (XEXP (x, i) != XEXP (y, i)) | |
2368 | return 0; | |
2369 | /* fall through. */ | |
2370 | case '0': | |
2371 | break; | |
2372 | ||
2373 | case 'E': | |
2374 | if (XVECLEN (x, i) != XVECLEN (y, i)) | |
2375 | return 0; | |
2376 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) | |
2377 | if (!rtx_renumbered_equal_p (XVECEXP (x, i, j), XVECEXP (y, i, j))) | |
2378 | return 0; | |
2379 | break; | |
2380 | ||
2381 | default: | |
2382 | abort (); | |
2383 | } | |
2384 | } | |
2385 | return 1; | |
2386 | } | |
2387 | \f | |
2388 | /* If X is a hard register or equivalent to one or a subregister of one, | |
2389 | return the hard register number. If X is a pseudo register that was not | |
2390 | assigned a hard register, return the pseudo register number. Otherwise, | |
2391 | return -1. Any rtx is valid for X. */ | |
2392 | ||
2393 | int | |
2394 | true_regnum (x) | |
2395 | rtx x; | |
2396 | { | |
2397 | if (GET_CODE (x) == REG) | |
2398 | { | |
2399 | if (REGNO (x) >= FIRST_PSEUDO_REGISTER && reg_renumber[REGNO (x)] >= 0) | |
2400 | return reg_renumber[REGNO (x)]; | |
2401 | return REGNO (x); | |
2402 | } | |
2403 | if (GET_CODE (x) == SUBREG) | |
2404 | { | |
2405 | int base = true_regnum (SUBREG_REG (x)); | |
2406 | if (base >= 0 && base < FIRST_PSEUDO_REGISTER) | |
701e46d0 | 2407 | return base + subreg_regno_offset (REGNO (SUBREG_REG (x)), |
2408 | GET_MODE (SUBREG_REG (x)), | |
2409 | SUBREG_BYTE (x), GET_MODE (x)); | |
5924de0b | 2410 | } |
2411 | return -1; | |
2412 | } |