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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" |
805e22b2 | 39 | #include "coretypes.h" |
40 | #include "tm.h" | |
5924de0b | 41 | #include "rtl.h" |
7953c610 | 42 | #include "tm_p.h" |
5924de0b | 43 | #include "flags.h" |
44 | #include "hard-reg-set.h" | |
45 | #include "regs.h" | |
5924de0b | 46 | #include "insn-config.h" |
fe3b47be | 47 | #include "insn-attr.h" |
0dbd1c74 | 48 | #include "recog.h" |
0a893c29 | 49 | #include "function.h" |
fa9157fe | 50 | #include "expr.h" |
5924de0b | 51 | #include "real.h" |
485aaaaf | 52 | #include "except.h" |
ce1fd7fc | 53 | #include "toplev.h" |
75eb327c | 54 | #include "reload.h" |
13488c51 | 55 | #include "predict.h" |
5924de0b | 56 | |
5924de0b | 57 | /* Optimize jump y; x: ... y: jumpif... x? |
58 | Don't know if it is worth bothering with. */ | |
59 | /* Optimize two cases of conditional jump to conditional jump? | |
60 | This can never delete any instruction or make anything dead, | |
61 | or even change what is live at any point. | |
62 | So perhaps let combiner do it. */ | |
63 | ||
805e22b2 | 64 | static void init_label_info PARAMS ((rtx)); |
bf73fcf4 | 65 | static void mark_all_labels PARAMS ((rtx)); |
38b9004f | 66 | static int duplicate_loop_exit_test PARAMS ((rtx)); |
38b9004f | 67 | static void delete_computation PARAMS ((rtx)); |
a8b5d014 | 68 | static void redirect_exp_1 PARAMS ((rtx *, rtx, rtx, rtx)); |
ba08b7e7 | 69 | static int redirect_exp PARAMS ((rtx, rtx, rtx)); |
70 | static void invert_exp_1 PARAMS ((rtx)); | |
71 | static int invert_exp PARAMS ((rtx)); | |
38b9004f | 72 | static int returnjump_p_1 PARAMS ((rtx *, void *)); |
73 | static void delete_prior_computation PARAMS ((rtx, rtx)); | |
60ecc450 | 74 | \f |
8b946ced | 75 | /* Alternate entry into the jump optimizer. This entry point only rebuilds |
76 | the JUMP_LABEL field in jumping insns and REG_LABEL notes in non-jumping | |
77 | instructions. */ | |
78 | void | |
79 | rebuild_jump_labels (f) | |
80 | rtx f; | |
81 | { | |
19cb6b50 | 82 | rtx insn; |
5924de0b | 83 | |
805e22b2 | 84 | init_label_info (f); |
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. */ | |
805e22b2 | 189 | static void |
e8d75e01 | 190 | init_label_info (f) |
191 | rtx f; | |
192 | { | |
e8d75e01 | 193 | rtx insn; |
194 | ||
195 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
805e22b2 | 196 | if (GET_CODE (insn) == CODE_LABEL) |
197 | LABEL_NUSES (insn) = (LABEL_PRESERVE_P (insn) != 0); | |
198 | else if (GET_CODE (insn) == JUMP_INSN) | |
199 | JUMP_LABEL (insn) = 0; | |
200 | else if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
201 | { | |
202 | rtx note, next; | |
e8d75e01 | 203 | |
805e22b2 | 204 | for (note = REG_NOTES (insn); note; note = next) |
205 | { | |
206 | next = XEXP (note, 1); | |
207 | if (REG_NOTE_KIND (note) == REG_LABEL | |
208 | && ! reg_mentioned_p (XEXP (note, 0), PATTERN (insn))) | |
209 | remove_note (insn, note); | |
210 | } | |
211 | } | |
e8d75e01 | 212 | } |
213 | ||
e8d75e01 | 214 | /* Mark the label each jump jumps to. |
fc4eaab7 | 215 | Combine consecutive labels, and count uses of labels. */ |
e8d75e01 | 216 | |
217 | static void | |
bf73fcf4 | 218 | mark_all_labels (f) |
e8d75e01 | 219 | rtx f; |
e8d75e01 | 220 | { |
221 | rtx insn; | |
222 | ||
223 | for (insn = f; insn; insn = NEXT_INSN (insn)) | |
9204e736 | 224 | if (INSN_P (insn)) |
e8d75e01 | 225 | { |
0e3150ce | 226 | if (GET_CODE (insn) == CALL_INSN |
227 | && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER) | |
228 | { | |
bf73fcf4 | 229 | mark_all_labels (XEXP (PATTERN (insn), 0)); |
230 | mark_all_labels (XEXP (PATTERN (insn), 1)); | |
231 | mark_all_labels (XEXP (PATTERN (insn), 2)); | |
af29e037 | 232 | |
233 | /* Canonicalize the tail recursion label attached to the | |
234 | CALL_PLACEHOLDER insn. */ | |
235 | if (XEXP (PATTERN (insn), 3)) | |
236 | { | |
237 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
238 | XEXP (PATTERN (insn), 3)); | |
bf73fcf4 | 239 | mark_jump_label (label_ref, insn, 0); |
af29e037 | 240 | XEXP (PATTERN (insn), 3) = XEXP (label_ref, 0); |
241 | } | |
242 | ||
0e3150ce | 243 | continue; |
244 | } | |
7113a566 | 245 | |
bf73fcf4 | 246 | mark_jump_label (PATTERN (insn), insn, 0); |
e8d75e01 | 247 | if (! INSN_DELETED_P (insn) && GET_CODE (insn) == JUMP_INSN) |
248 | { | |
d3ff0f75 | 249 | /* When we know the LABEL_REF contained in a REG used in |
250 | an indirect jump, we'll have a REG_LABEL note so that | |
251 | flow can tell where it's going. */ | |
252 | if (JUMP_LABEL (insn) == 0) | |
253 | { | |
254 | rtx label_note = find_reg_note (insn, REG_LABEL, NULL_RTX); | |
255 | if (label_note) | |
256 | { | |
257 | /* But a LABEL_REF around the REG_LABEL note, so | |
258 | that we can canonicalize it. */ | |
259 | rtx label_ref = gen_rtx_LABEL_REF (VOIDmode, | |
260 | XEXP (label_note, 0)); | |
261 | ||
bf73fcf4 | 262 | mark_jump_label (label_ref, insn, 0); |
d3ff0f75 | 263 | XEXP (label_note, 0) = XEXP (label_ref, 0); |
264 | JUMP_LABEL (insn) = XEXP (label_note, 0); | |
265 | } | |
266 | } | |
e8d75e01 | 267 | } |
268 | } | |
269 | } | |
270 | ||
5924de0b | 271 | /* LOOP_START is a NOTE_INSN_LOOP_BEG note that is followed by an unconditional |
272 | jump. Assume that this unconditional jump is to the exit test code. If | |
273 | the code is sufficiently simple, make a copy of it before INSN, | |
274 | followed by a jump to the exit of the loop. Then delete the unconditional | |
275 | jump after INSN. | |
276 | ||
5924de0b | 277 | Return 1 if we made the change, else 0. |
278 | ||
279 | This is only safe immediately after a regscan pass because it uses the | |
280 | values of regno_first_uid and regno_last_uid. */ | |
281 | ||
282 | static int | |
283 | duplicate_loop_exit_test (loop_start) | |
284 | rtx loop_start; | |
285 | { | |
3a348c93 | 286 | rtx insn, set, reg, p, link; |
4e717234 | 287 | rtx copy = 0, first_copy = 0; |
5924de0b | 288 | int num_insns = 0; |
289 | rtx exitcode = NEXT_INSN (JUMP_LABEL (next_nonnote_insn (loop_start))); | |
290 | rtx lastexit; | |
291 | int max_reg = max_reg_num (); | |
292 | rtx *reg_map = 0; | |
ea918419 | 293 | rtx loop_pre_header_label; |
5924de0b | 294 | |
295 | /* Scan the exit code. We do not perform this optimization if any insn: | |
296 | ||
297 | is a CALL_INSN | |
298 | is a CODE_LABEL | |
299 | has a REG_RETVAL or REG_LIBCALL note (hard to adjust) | |
300 | is a NOTE_INSN_LOOP_BEG because this means we have a nested loop | |
17b1950c | 301 | |
302 | We also do not do this if we find an insn with ASM_OPERANDS. While | |
303 | this restriction should not be necessary, copying an insn with | |
304 | ASM_OPERANDS can confuse asm_noperands in some cases. | |
5924de0b | 305 | |
306 | Also, don't do this if the exit code is more than 20 insns. */ | |
307 | ||
308 | for (insn = exitcode; | |
309 | insn | |
310 | && ! (GET_CODE (insn) == NOTE | |
311 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END); | |
312 | insn = NEXT_INSN (insn)) | |
313 | { | |
314 | switch (GET_CODE (insn)) | |
315 | { | |
316 | case CODE_LABEL: | |
317 | case CALL_INSN: | |
318 | return 0; | |
319 | case NOTE: | |
ec6be638 | 320 | |
321 | if (optimize < 2 | |
322 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
323 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)) | |
324 | /* If we were to duplicate this code, we would not move | |
325 | the BLOCK notes, and so debugging the moved code would | |
326 | be difficult. Thus, we only move the code with -O2 or | |
327 | higher. */ | |
328 | return 0; | |
329 | ||
5924de0b | 330 | break; |
331 | case JUMP_INSN: | |
332 | case INSN: | |
7665c376 | 333 | /* The code below would grossly mishandle REG_WAS_0 notes, |
334 | so get rid of them here. */ | |
335 | while ((p = find_reg_note (insn, REG_WAS_0, NULL_RTX)) != 0) | |
336 | remove_note (insn, p); | |
5924de0b | 337 | if (++num_insns > 20 |
1bb04728 | 338 | || find_reg_note (insn, REG_RETVAL, NULL_RTX) |
928d57e3 | 339 | || find_reg_note (insn, REG_LIBCALL, NULL_RTX)) |
5924de0b | 340 | return 0; |
341 | break; | |
0dbd1c74 | 342 | default: |
343 | break; | |
5924de0b | 344 | } |
345 | } | |
346 | ||
347 | /* Unless INSN is zero, we can do the optimization. */ | |
348 | if (insn == 0) | |
349 | return 0; | |
350 | ||
351 | lastexit = insn; | |
352 | ||
353 | /* See if any insn sets a register only used in the loop exit code and | |
354 | not a user variable. If so, replace it with a new register. */ | |
355 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
356 | if (GET_CODE (insn) == INSN | |
357 | && (set = single_set (insn)) != 0 | |
3a348c93 | 358 | && ((reg = SET_DEST (set), GET_CODE (reg) == REG) |
359 | || (GET_CODE (reg) == SUBREG | |
360 | && (reg = SUBREG_REG (reg), GET_CODE (reg) == REG))) | |
361 | && REGNO (reg) >= FIRST_PSEUDO_REGISTER | |
394685a4 | 362 | && REGNO_FIRST_UID (REGNO (reg)) == INSN_UID (insn)) |
5924de0b | 363 | { |
364 | for (p = NEXT_INSN (insn); p != lastexit; p = NEXT_INSN (p)) | |
394685a4 | 365 | if (REGNO_LAST_UID (REGNO (reg)) == INSN_UID (p)) |
5924de0b | 366 | break; |
367 | ||
368 | if (p != lastexit) | |
369 | { | |
370 | /* We can do the replacement. Allocate reg_map if this is the | |
371 | first replacement we found. */ | |
372 | if (reg_map == 0) | |
8b861be4 | 373 | reg_map = (rtx *) xcalloc (max_reg, sizeof (rtx)); |
5924de0b | 374 | |
3a348c93 | 375 | REG_LOOP_TEST_P (reg) = 1; |
5924de0b | 376 | |
3a348c93 | 377 | reg_map[REGNO (reg)] = gen_reg_rtx (GET_MODE (reg)); |
5924de0b | 378 | } |
379 | } | |
ea918419 | 380 | loop_pre_header_label = gen_label_rtx (); |
5924de0b | 381 | |
382 | /* Now copy each insn. */ | |
383 | for (insn = exitcode; insn != lastexit; insn = NEXT_INSN (insn)) | |
4e717234 | 384 | { |
385 | switch (GET_CODE (insn)) | |
386 | { | |
387 | case BARRIER: | |
388 | copy = emit_barrier_before (loop_start); | |
389 | break; | |
390 | case NOTE: | |
391 | /* Only copy line-number notes. */ | |
392 | if (NOTE_LINE_NUMBER (insn) >= 0) | |
393 | { | |
394 | copy = emit_note_before (NOTE_LINE_NUMBER (insn), loop_start); | |
395 | NOTE_SOURCE_FILE (copy) = NOTE_SOURCE_FILE (insn); | |
396 | } | |
397 | break; | |
7113a566 | 398 | |
4e717234 | 399 | case INSN: |
928d57e3 | 400 | copy = emit_insn_before (copy_insn (PATTERN (insn)), loop_start); |
4e717234 | 401 | if (reg_map) |
402 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
7113a566 | 403 | |
bf73fcf4 | 404 | mark_jump_label (PATTERN (copy), copy, 0); |
ab87d1bc | 405 | INSN_SCOPE (copy) = INSN_SCOPE (insn); |
7113a566 | 406 | |
4e717234 | 407 | /* Copy all REG_NOTES except REG_LABEL since mark_jump_label will |
408 | make them. */ | |
409 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
410 | if (REG_NOTE_KIND (link) != REG_LABEL) | |
74b0991d | 411 | { |
412 | if (GET_CODE (link) == EXPR_LIST) | |
413 | REG_NOTES (copy) | |
414 | = copy_insn_1 (gen_rtx_EXPR_LIST (REG_NOTE_KIND (link), | |
415 | XEXP (link, 0), | |
416 | REG_NOTES (copy))); | |
417 | else | |
418 | REG_NOTES (copy) | |
419 | = copy_insn_1 (gen_rtx_INSN_LIST (REG_NOTE_KIND (link), | |
420 | XEXP (link, 0), | |
421 | REG_NOTES (copy))); | |
422 | } | |
423 | ||
4e717234 | 424 | if (reg_map && REG_NOTES (copy)) |
425 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
426 | break; | |
7113a566 | 427 | |
4e717234 | 428 | case JUMP_INSN: |
7113a566 | 429 | copy = emit_jump_insn_before (copy_insn (PATTERN (insn)), |
430 | loop_start); | |
ab87d1bc | 431 | INSN_SCOPE (copy) = INSN_SCOPE (insn); |
4e717234 | 432 | if (reg_map) |
433 | replace_regs (PATTERN (copy), reg_map, max_reg, 1); | |
bf73fcf4 | 434 | mark_jump_label (PATTERN (copy), copy, 0); |
4e717234 | 435 | if (REG_NOTES (insn)) |
436 | { | |
928d57e3 | 437 | REG_NOTES (copy) = copy_insn_1 (REG_NOTES (insn)); |
4e717234 | 438 | if (reg_map) |
439 | replace_regs (REG_NOTES (copy), reg_map, max_reg, 1); | |
440 | } | |
7113a566 | 441 | |
13488c51 | 442 | /* Predict conditional jump that do make loop looping as taken. |
443 | Other jumps are probably exit conditions, so predict | |
444 | them as untaken. */ | |
445 | if (any_condjump_p (copy)) | |
446 | { | |
447 | rtx label = JUMP_LABEL (copy); | |
448 | if (label) | |
449 | { | |
4361b500 | 450 | /* The jump_insn after loop_start should be followed |
451 | by barrier and loopback label. */ | |
452 | if (prev_nonnote_insn (label) | |
ea918419 | 453 | && (prev_nonnote_insn (prev_nonnote_insn (label)) |
454 | == next_nonnote_insn (loop_start))) | |
455 | { | |
456 | predict_insn_def (copy, PRED_LOOP_HEADER, TAKEN); | |
457 | /* To keep pre-header, we need to redirect all loop | |
458 | entrances before the LOOP_BEG note. */ | |
459 | redirect_jump (copy, loop_pre_header_label, 0); | |
460 | } | |
13488c51 | 461 | else |
462 | predict_insn_def (copy, PRED_LOOP_HEADER, NOT_TAKEN); | |
463 | } | |
464 | } | |
4e717234 | 465 | break; |
7113a566 | 466 | |
4e717234 | 467 | default: |
468 | abort (); | |
469 | } | |
5924de0b | 470 | |
4e717234 | 471 | /* Record the first insn we copied. We need it so that we can |
472 | scan the copied insns for new pseudo registers. */ | |
473 | if (! first_copy) | |
474 | first_copy = copy; | |
475 | } | |
5924de0b | 476 | |
477 | /* Now clean up by emitting a jump to the end label and deleting the jump | |
478 | at the start of the loop. */ | |
b8778d98 | 479 | if (! copy || GET_CODE (copy) != BARRIER) |
5924de0b | 480 | { |
481 | copy = emit_jump_insn_before (gen_jump (get_label_after (insn)), | |
482 | loop_start); | |
4e717234 | 483 | |
484 | /* Record the first insn we copied. We need it so that we can | |
485 | scan the copied insns for new pseudo registers. This may not | |
486 | be strictly necessary since we should have copied at least one | |
487 | insn above. But I am going to be safe. */ | |
488 | if (! first_copy) | |
489 | first_copy = copy; | |
490 | ||
bf73fcf4 | 491 | mark_jump_label (PATTERN (copy), copy, 0); |
5924de0b | 492 | emit_barrier_before (loop_start); |
493 | } | |
494 | ||
ea918419 | 495 | emit_label_before (loop_pre_header_label, loop_start); |
496 | ||
4e717234 | 497 | /* Now scan from the first insn we copied to the last insn we copied |
498 | (copy) for new pseudo registers. Do this after the code to jump to | |
499 | the end label since that might create a new pseudo too. */ | |
500 | reg_scan_update (first_copy, copy, max_reg); | |
501 | ||
5924de0b | 502 | /* Mark the exit code as the virtual top of the converted loop. */ |
503 | emit_note_before (NOTE_INSN_LOOP_VTOP, exitcode); | |
504 | ||
e4bf866d | 505 | delete_related_insns (next_nonnote_insn (loop_start)); |
7113a566 | 506 | |
8b861be4 | 507 | /* Clean up. */ |
508 | if (reg_map) | |
509 | free (reg_map); | |
92d3c3ad | 510 | |
5924de0b | 511 | return 1; |
512 | } | |
513 | \f | |
74b0991d | 514 | /* Move all block-beg, block-end, loop-beg, loop-cont, loop-vtop, loop-end, |
3612339f | 515 | notes between START and END out before START. START and END may be such |
516 | notes. Returns the values of the new starting and ending insns, which | |
87dc0300 | 517 | may be different if the original ones were such notes. |
518 | Return true if there were only such notes and no real instructions. */ | |
5924de0b | 519 | |
87dc0300 | 520 | bool |
3612339f | 521 | squeeze_notes (startp, endp) |
522 | rtx* startp; | |
523 | rtx* endp; | |
5924de0b | 524 | { |
3612339f | 525 | rtx start = *startp; |
526 | rtx end = *endp; | |
527 | ||
5924de0b | 528 | rtx insn; |
529 | rtx next; | |
3612339f | 530 | rtx last = NULL; |
531 | rtx past_end = NEXT_INSN (end); | |
5924de0b | 532 | |
3612339f | 533 | for (insn = start; insn != past_end; insn = next) |
5924de0b | 534 | { |
535 | next = NEXT_INSN (insn); | |
536 | if (GET_CODE (insn) == NOTE | |
537 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END | |
538 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
539 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG | |
540 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END | |
541 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT | |
a196d160 | 542 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_VTOP)) |
5924de0b | 543 | { |
d2d45541 | 544 | if (insn == start) |
545 | start = next; | |
546 | else | |
547 | { | |
548 | rtx prev = PREV_INSN (insn); | |
549 | PREV_INSN (insn) = PREV_INSN (start); | |
550 | NEXT_INSN (insn) = start; | |
551 | NEXT_INSN (PREV_INSN (insn)) = insn; | |
552 | PREV_INSN (NEXT_INSN (insn)) = insn; | |
553 | NEXT_INSN (prev) = next; | |
554 | PREV_INSN (next) = prev; | |
555 | } | |
5924de0b | 556 | } |
3612339f | 557 | else |
558 | last = insn; | |
5924de0b | 559 | } |
d2d45541 | 560 | |
87dc0300 | 561 | /* There were no real instructions. */ |
3612339f | 562 | if (start == past_end) |
87dc0300 | 563 | return true; |
3612339f | 564 | |
565 | end = last; | |
566 | ||
567 | *startp = start; | |
568 | *endp = end; | |
87dc0300 | 569 | return false; |
5924de0b | 570 | } |
571 | \f | |
5924de0b | 572 | /* Return the label before INSN, or put a new label there. */ |
573 | ||
574 | rtx | |
575 | get_label_before (insn) | |
576 | rtx insn; | |
577 | { | |
578 | rtx label; | |
579 | ||
580 | /* Find an existing label at this point | |
581 | or make a new one if there is none. */ | |
582 | label = prev_nonnote_insn (insn); | |
583 | ||
584 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
585 | { | |
586 | rtx prev = PREV_INSN (insn); | |
587 | ||
5924de0b | 588 | label = gen_label_rtx (); |
589 | emit_label_after (label, prev); | |
590 | LABEL_NUSES (label) = 0; | |
591 | } | |
592 | return label; | |
593 | } | |
594 | ||
595 | /* Return the label after INSN, or put a new label there. */ | |
596 | ||
597 | rtx | |
598 | get_label_after (insn) | |
599 | rtx insn; | |
600 | { | |
601 | rtx label; | |
602 | ||
603 | /* Find an existing label at this point | |
604 | or make a new one if there is none. */ | |
605 | label = next_nonnote_insn (insn); | |
606 | ||
607 | if (label == 0 || GET_CODE (label) != CODE_LABEL) | |
608 | { | |
5924de0b | 609 | label = gen_label_rtx (); |
610 | emit_label_after (label, insn); | |
611 | LABEL_NUSES (label) = 0; | |
612 | } | |
613 | return label; | |
614 | } | |
615 | \f | |
fa8b3d85 | 616 | /* Given a comparison (CODE ARG0 ARG1), inside an insn, INSN, return a code |
8e98892d | 617 | of reversed comparison if it is possible to do so. Otherwise return UNKNOWN. |
618 | UNKNOWN may be returned in case we are having CC_MODE compare and we don't | |
619 | know whether it's source is floating point or integer comparison. Machine | |
620 | description should define REVERSIBLE_CC_MODE and REVERSE_CONDITION macros | |
621 | to help this function avoid overhead in these cases. */ | |
622 | enum rtx_code | |
623 | reversed_comparison_code_parts (code, arg0, arg1, insn) | |
624 | rtx insn, arg0, arg1; | |
625 | enum rtx_code code; | |
5924de0b | 626 | { |
8e98892d | 627 | enum machine_mode mode; |
5924de0b | 628 | |
629 | /* If this is not actually a comparison, we can't reverse it. */ | |
8e98892d | 630 | if (GET_RTX_CLASS (code) != '<') |
631 | return UNKNOWN; | |
632 | ||
633 | mode = GET_MODE (arg0); | |
634 | if (mode == VOIDmode) | |
635 | mode = GET_MODE (arg1); | |
636 | ||
637 | /* First see if machine description supply us way to reverse the comparison. | |
638 | Give it priority over everything else to allow machine description to do | |
639 | tricks. */ | |
640 | #ifdef REVERSIBLE_CC_MODE | |
0ec244e1 | 641 | if (GET_MODE_CLASS (mode) == MODE_CC |
8e98892d | 642 | && REVERSIBLE_CC_MODE (mode)) |
643 | { | |
644 | #ifdef REVERSE_CONDITION | |
85fc0ad1 | 645 | return REVERSE_CONDITION (code, mode); |
8e98892d | 646 | #endif |
85fc0ad1 | 647 | return reverse_condition (code); |
648 | } | |
8e98892d | 649 | #endif |
5924de0b | 650 | |
fa8b3d85 | 651 | /* Try a few special cases based on the comparison code. */ |
8e98892d | 652 | switch (code) |
653 | { | |
85fc0ad1 | 654 | case GEU: |
655 | case GTU: | |
656 | case LEU: | |
657 | case LTU: | |
658 | case NE: | |
659 | case EQ: | |
660 | /* It is always safe to reverse EQ and NE, even for the floating | |
661 | point. Similary the unsigned comparisons are never used for | |
662 | floating point so we can reverse them in the default way. */ | |
663 | return reverse_condition (code); | |
664 | case ORDERED: | |
665 | case UNORDERED: | |
666 | case LTGT: | |
667 | case UNEQ: | |
668 | /* In case we already see unordered comparison, we can be sure to | |
669 | be dealing with floating point so we don't need any more tests. */ | |
670 | return reverse_condition_maybe_unordered (code); | |
671 | case UNLT: | |
672 | case UNLE: | |
673 | case UNGT: | |
674 | case UNGE: | |
675 | /* We don't have safe way to reverse these yet. */ | |
676 | return UNKNOWN; | |
677 | default: | |
678 | break; | |
8e98892d | 679 | } |
680 | ||
8e98892d | 681 | if (GET_MODE_CLASS (mode) == MODE_CC |
5924de0b | 682 | #ifdef HAVE_cc0 |
683 | || arg0 == cc0_rtx | |
684 | #endif | |
685 | ) | |
686 | { | |
8e98892d | 687 | rtx prev; |
688 | /* Try to search for the comparison to determine the real mode. | |
689 | This code is expensive, but with sane machine description it | |
690 | will be never used, since REVERSIBLE_CC_MODE will return true | |
691 | in all cases. */ | |
111f2389 | 692 | if (! insn) |
8e98892d | 693 | return UNKNOWN; |
7113a566 | 694 | |
7014838c | 695 | for (prev = prev_nonnote_insn (insn); |
696 | prev != 0 && GET_CODE (prev) != CODE_LABEL; | |
697 | prev = prev_nonnote_insn (prev)) | |
8e98892d | 698 | { |
699 | rtx set = set_of (arg0, prev); | |
700 | if (set && GET_CODE (set) == SET | |
701 | && rtx_equal_p (SET_DEST (set), arg0)) | |
702 | { | |
703 | rtx src = SET_SRC (set); | |
5924de0b | 704 | |
8e98892d | 705 | if (GET_CODE (src) == COMPARE) |
706 | { | |
707 | rtx comparison = src; | |
708 | arg0 = XEXP (src, 0); | |
709 | mode = GET_MODE (arg0); | |
710 | if (mode == VOIDmode) | |
711 | mode = GET_MODE (XEXP (comparison, 1)); | |
712 | break; | |
713 | } | |
dd5b4b36 | 714 | /* We can get past reg-reg moves. This may be useful for model |
8e98892d | 715 | of i387 comparisons that first move flag registers around. */ |
716 | if (REG_P (src)) | |
717 | { | |
718 | arg0 = src; | |
719 | continue; | |
720 | } | |
721 | } | |
722 | /* If register is clobbered in some ununderstandable way, | |
723 | give up. */ | |
724 | if (set) | |
725 | return UNKNOWN; | |
726 | } | |
5924de0b | 727 | } |
728 | ||
920d0fb5 | 729 | /* Test for an integer condition, or a floating-point comparison |
730 | in which NaNs can be ignored. */ | |
8e98892d | 731 | if (GET_CODE (arg0) == CONST_INT |
732 | || (GET_MODE (arg0) != VOIDmode | |
733 | && GET_MODE_CLASS (mode) != MODE_CC | |
920d0fb5 | 734 | && !HONOR_NANS (mode))) |
8e98892d | 735 | return reverse_condition (code); |
736 | ||
737 | return UNKNOWN; | |
738 | } | |
739 | ||
740 | /* An wrapper around the previous function to take COMPARISON as rtx | |
741 | expression. This simplifies many callers. */ | |
742 | enum rtx_code | |
743 | reversed_comparison_code (comparison, insn) | |
744 | rtx comparison, insn; | |
745 | { | |
746 | if (GET_RTX_CLASS (GET_CODE (comparison)) != '<') | |
747 | return UNKNOWN; | |
748 | return reversed_comparison_code_parts (GET_CODE (comparison), | |
749 | XEXP (comparison, 0), | |
750 | XEXP (comparison, 1), insn); | |
751 | } | |
752 | \f | |
a4110d9a | 753 | /* Given an rtx-code for a comparison, return the code for the negated |
754 | comparison. If no such code exists, return UNKNOWN. | |
755 | ||
756 | WATCH OUT! reverse_condition is not safe to use on a jump that might | |
757 | be acting on the results of an IEEE floating point comparison, because | |
7113a566 | 758 | of the special treatment of non-signaling nans in comparisons. |
8e98892d | 759 | Use reversed_comparison_code instead. */ |
5924de0b | 760 | |
761 | enum rtx_code | |
762 | reverse_condition (code) | |
763 | enum rtx_code code; | |
764 | { | |
765 | switch (code) | |
766 | { | |
767 | case EQ: | |
768 | return NE; | |
5924de0b | 769 | case NE: |
770 | return EQ; | |
5924de0b | 771 | case GT: |
772 | return LE; | |
5924de0b | 773 | case GE: |
774 | return LT; | |
5924de0b | 775 | case LT: |
776 | return GE; | |
5924de0b | 777 | case LE: |
778 | return GT; | |
5924de0b | 779 | case GTU: |
780 | return LEU; | |
5924de0b | 781 | case GEU: |
782 | return LTU; | |
5924de0b | 783 | case LTU: |
784 | return GEU; | |
5924de0b | 785 | case LEU: |
786 | return GTU; | |
a4110d9a | 787 | case UNORDERED: |
788 | return ORDERED; | |
789 | case ORDERED: | |
790 | return UNORDERED; | |
791 | ||
792 | case UNLT: | |
793 | case UNLE: | |
794 | case UNGT: | |
795 | case UNGE: | |
796 | case UNEQ: | |
79777bad | 797 | case LTGT: |
a4110d9a | 798 | return UNKNOWN; |
5924de0b | 799 | |
800 | default: | |
801 | abort (); | |
5924de0b | 802 | } |
803 | } | |
804 | ||
79777bad | 805 | /* Similar, but we're allowed to generate unordered comparisons, which |
806 | makes it safe for IEEE floating-point. Of course, we have to recognize | |
807 | that the target will support them too... */ | |
808 | ||
809 | enum rtx_code | |
810 | reverse_condition_maybe_unordered (code) | |
811 | enum rtx_code code; | |
812 | { | |
79777bad | 813 | switch (code) |
814 | { | |
815 | case EQ: | |
816 | return NE; | |
817 | case NE: | |
818 | return EQ; | |
819 | case GT: | |
820 | return UNLE; | |
821 | case GE: | |
822 | return UNLT; | |
823 | case LT: | |
824 | return UNGE; | |
825 | case LE: | |
826 | return UNGT; | |
827 | case LTGT: | |
828 | return UNEQ; | |
79777bad | 829 | case UNORDERED: |
830 | return ORDERED; | |
831 | case ORDERED: | |
832 | return UNORDERED; | |
833 | case UNLT: | |
834 | return GE; | |
835 | case UNLE: | |
836 | return GT; | |
837 | case UNGT: | |
838 | return LE; | |
839 | case UNGE: | |
840 | return LT; | |
841 | case UNEQ: | |
842 | return LTGT; | |
843 | ||
844 | default: | |
845 | abort (); | |
846 | } | |
847 | } | |
848 | ||
5924de0b | 849 | /* Similar, but return the code when two operands of a comparison are swapped. |
850 | This IS safe for IEEE floating-point. */ | |
851 | ||
852 | enum rtx_code | |
853 | swap_condition (code) | |
854 | enum rtx_code code; | |
855 | { | |
856 | switch (code) | |
857 | { | |
858 | case EQ: | |
859 | case NE: | |
a4110d9a | 860 | case UNORDERED: |
861 | case ORDERED: | |
862 | case UNEQ: | |
79777bad | 863 | case LTGT: |
5924de0b | 864 | return code; |
865 | ||
866 | case GT: | |
867 | return LT; | |
5924de0b | 868 | case GE: |
869 | return LE; | |
5924de0b | 870 | case LT: |
871 | return GT; | |
5924de0b | 872 | case LE: |
873 | return GE; | |
5924de0b | 874 | case GTU: |
875 | return LTU; | |
5924de0b | 876 | case GEU: |
877 | return LEU; | |
5924de0b | 878 | case LTU: |
879 | return GTU; | |
5924de0b | 880 | case LEU: |
881 | return GEU; | |
a4110d9a | 882 | case UNLT: |
883 | return UNGT; | |
884 | case UNLE: | |
885 | return UNGE; | |
886 | case UNGT: | |
887 | return UNLT; | |
888 | case UNGE: | |
889 | return UNLE; | |
890 | ||
5924de0b | 891 | default: |
892 | abort (); | |
5924de0b | 893 | } |
894 | } | |
895 | ||
896 | /* Given a comparison CODE, return the corresponding unsigned comparison. | |
897 | If CODE is an equality comparison or already an unsigned comparison, | |
898 | CODE is returned. */ | |
899 | ||
900 | enum rtx_code | |
901 | unsigned_condition (code) | |
902 | enum rtx_code code; | |
903 | { | |
904 | switch (code) | |
905 | { | |
906 | case EQ: | |
907 | case NE: | |
908 | case GTU: | |
909 | case GEU: | |
910 | case LTU: | |
911 | case LEU: | |
912 | return code; | |
913 | ||
914 | case GT: | |
915 | return GTU; | |
5924de0b | 916 | case GE: |
917 | return GEU; | |
5924de0b | 918 | case LT: |
919 | return LTU; | |
5924de0b | 920 | case LE: |
921 | return LEU; | |
922 | ||
923 | default: | |
924 | abort (); | |
925 | } | |
926 | } | |
927 | ||
928 | /* Similarly, return the signed version of a comparison. */ | |
929 | ||
930 | enum rtx_code | |
931 | signed_condition (code) | |
932 | enum rtx_code code; | |
933 | { | |
934 | switch (code) | |
935 | { | |
936 | case EQ: | |
937 | case NE: | |
938 | case GT: | |
939 | case GE: | |
940 | case LT: | |
941 | case LE: | |
942 | return code; | |
943 | ||
944 | case GTU: | |
945 | return GT; | |
5924de0b | 946 | case GEU: |
947 | return GE; | |
5924de0b | 948 | case LTU: |
949 | return LT; | |
5924de0b | 950 | case LEU: |
951 | return LE; | |
952 | ||
953 | default: | |
954 | abort (); | |
955 | } | |
956 | } | |
957 | \f | |
6ef828f9 | 958 | /* Return nonzero if CODE1 is more strict than CODE2, i.e., if the |
5924de0b | 959 | truth of CODE1 implies the truth of CODE2. */ |
960 | ||
961 | int | |
962 | comparison_dominates_p (code1, code2) | |
963 | enum rtx_code code1, code2; | |
964 | { | |
ca7744c6 | 965 | /* UNKNOWN comparison codes can happen as a result of trying to revert |
966 | comparison codes. | |
967 | They can't match anything, so we have to reject them here. */ | |
968 | if (code1 == UNKNOWN || code2 == UNKNOWN) | |
969 | return 0; | |
970 | ||
5924de0b | 971 | if (code1 == code2) |
972 | return 1; | |
973 | ||
974 | switch (code1) | |
975 | { | |
5aa3f5e2 | 976 | case UNEQ: |
977 | if (code2 == UNLE || code2 == UNGE) | |
978 | return 1; | |
979 | break; | |
980 | ||
5924de0b | 981 | case EQ: |
79777bad | 982 | if (code2 == LE || code2 == LEU || code2 == GE || code2 == GEU |
983 | || code2 == ORDERED) | |
5924de0b | 984 | return 1; |
985 | break; | |
986 | ||
5aa3f5e2 | 987 | case UNLT: |
988 | if (code2 == UNLE || code2 == NE) | |
989 | return 1; | |
990 | break; | |
991 | ||
5924de0b | 992 | case LT: |
5aa3f5e2 | 993 | if (code2 == LE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
994 | return 1; | |
995 | break; | |
996 | ||
997 | case UNGT: | |
998 | if (code2 == UNGE || code2 == NE) | |
5924de0b | 999 | return 1; |
1000 | break; | |
1001 | ||
1002 | case GT: | |
5aa3f5e2 | 1003 | if (code2 == GE || code2 == NE || code2 == ORDERED || code2 == LTGT) |
79777bad | 1004 | return 1; |
1005 | break; | |
1006 | ||
1007 | case GE: | |
1008 | case LE: | |
1009 | if (code2 == ORDERED) | |
1010 | return 1; | |
1011 | break; | |
1012 | ||
1013 | case LTGT: | |
1014 | if (code2 == NE || code2 == ORDERED) | |
5924de0b | 1015 | return 1; |
1016 | break; | |
1017 | ||
1018 | case LTU: | |
11088b43 | 1019 | if (code2 == LEU || code2 == NE) |
5924de0b | 1020 | return 1; |
1021 | break; | |
1022 | ||
1023 | case GTU: | |
11088b43 | 1024 | if (code2 == GEU || code2 == NE) |
5924de0b | 1025 | return 1; |
1026 | break; | |
79777bad | 1027 | |
1028 | case UNORDERED: | |
5aa3f5e2 | 1029 | if (code2 == NE || code2 == UNEQ || code2 == UNLE || code2 == UNLT |
1030 | || code2 == UNGE || code2 == UNGT) | |
79777bad | 1031 | return 1; |
1032 | break; | |
7113a566 | 1033 | |
0dbd1c74 | 1034 | default: |
1035 | break; | |
5924de0b | 1036 | } |
1037 | ||
1038 | return 0; | |
1039 | } | |
1040 | \f | |
1041 | /* Return 1 if INSN is an unconditional jump and nothing else. */ | |
1042 | ||
1043 | int | |
1044 | simplejump_p (insn) | |
1045 | rtx insn; | |
1046 | { | |
8d472058 | 1047 | return (GET_CODE (insn) == JUMP_INSN |
1048 | && GET_CODE (PATTERN (insn)) == SET | |
1049 | && GET_CODE (SET_DEST (PATTERN (insn))) == PC | |
1050 | && GET_CODE (SET_SRC (PATTERN (insn))) == LABEL_REF); | |
5924de0b | 1051 | } |
1052 | ||
1053 | /* Return nonzero if INSN is a (possibly) conditional jump | |
7113a566 | 1054 | and nothing more. |
1055 | ||
d670e794 | 1056 | Use this function is deprecated, since we need to support combined |
1057 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
5924de0b | 1058 | |
1059 | int | |
1060 | condjump_p (insn) | |
1061 | rtx insn; | |
1062 | { | |
19cb6b50 | 1063 | rtx x = PATTERN (insn); |
7014838c | 1064 | |
1065 | if (GET_CODE (x) != SET | |
1066 | || GET_CODE (SET_DEST (x)) != PC) | |
4fbe8fa7 | 1067 | return 0; |
7014838c | 1068 | |
1069 | x = SET_SRC (x); | |
1070 | if (GET_CODE (x) == LABEL_REF) | |
4fbe8fa7 | 1071 | return 1; |
7113a566 | 1072 | else |
1073 | return (GET_CODE (x) == IF_THEN_ELSE | |
1074 | && ((GET_CODE (XEXP (x, 2)) == PC | |
1075 | && (GET_CODE (XEXP (x, 1)) == LABEL_REF | |
1076 | || GET_CODE (XEXP (x, 1)) == RETURN)) | |
1077 | || (GET_CODE (XEXP (x, 1)) == PC | |
1078 | && (GET_CODE (XEXP (x, 2)) == LABEL_REF | |
1079 | || GET_CODE (XEXP (x, 2)) == RETURN)))); | |
7014838c | 1080 | |
4fbe8fa7 | 1081 | return 0; |
1082 | } | |
1083 | ||
7014838c | 1084 | /* Return nonzero if INSN is a (possibly) conditional jump inside a |
3a941ad5 | 1085 | PARALLEL. |
7113a566 | 1086 | |
d670e794 | 1087 | Use this function is deprecated, since we need to support combined |
1088 | branch and compare insns. Use any_condjump_p instead whenever possible. */ | |
4fbe8fa7 | 1089 | |
1090 | int | |
1091 | condjump_in_parallel_p (insn) | |
1092 | rtx insn; | |
1093 | { | |
19cb6b50 | 1094 | rtx x = PATTERN (insn); |
4fbe8fa7 | 1095 | |
1096 | if (GET_CODE (x) != PARALLEL) | |
1097 | return 0; | |
1098 | else | |
1099 | x = XVECEXP (x, 0, 0); | |
1100 | ||
5924de0b | 1101 | if (GET_CODE (x) != SET) |
1102 | return 0; | |
1103 | if (GET_CODE (SET_DEST (x)) != PC) | |
1104 | return 0; | |
1105 | if (GET_CODE (SET_SRC (x)) == LABEL_REF) | |
1106 | return 1; | |
1107 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) | |
1108 | return 0; | |
1109 | if (XEXP (SET_SRC (x), 2) == pc_rtx | |
1110 | && (GET_CODE (XEXP (SET_SRC (x), 1)) == LABEL_REF | |
1111 | || GET_CODE (XEXP (SET_SRC (x), 1)) == RETURN)) | |
1112 | return 1; | |
1113 | if (XEXP (SET_SRC (x), 1) == pc_rtx | |
1114 | && (GET_CODE (XEXP (SET_SRC (x), 2)) == LABEL_REF | |
1115 | || GET_CODE (XEXP (SET_SRC (x), 2)) == RETURN)) | |
1116 | return 1; | |
1117 | return 0; | |
1118 | } | |
1119 | ||
d670e794 | 1120 | /* Return set of PC, otherwise NULL. */ |
1121 | ||
3a941ad5 | 1122 | rtx |
1123 | pc_set (insn) | |
1124 | rtx insn; | |
1125 | { | |
1126 | rtx pat; | |
1127 | if (GET_CODE (insn) != JUMP_INSN) | |
d670e794 | 1128 | return NULL_RTX; |
3a941ad5 | 1129 | pat = PATTERN (insn); |
d670e794 | 1130 | |
1131 | /* The set is allowed to appear either as the insn pattern or | |
1132 | the first set in a PARALLEL. */ | |
1133 | if (GET_CODE (pat) == PARALLEL) | |
1134 | pat = XVECEXP (pat, 0, 0); | |
3a941ad5 | 1135 | if (GET_CODE (pat) == SET && GET_CODE (SET_DEST (pat)) == PC) |
1136 | return pat; | |
d670e794 | 1137 | |
1138 | return NULL_RTX; | |
3a941ad5 | 1139 | } |
1140 | ||
d670e794 | 1141 | /* Return true when insn is an unconditional direct jump, |
1142 | possibly bundled inside a PARALLEL. */ | |
1143 | ||
3a941ad5 | 1144 | int |
1145 | any_uncondjump_p (insn) | |
1146 | rtx insn; | |
1147 | { | |
1148 | rtx x = pc_set (insn); | |
1149 | if (!x) | |
1150 | return 0; | |
1151 | if (GET_CODE (SET_SRC (x)) != LABEL_REF) | |
1152 | return 0; | |
1153 | return 1; | |
1154 | } | |
1155 | ||
d670e794 | 1156 | /* Return true when insn is a conditional jump. This function works for |
3a941ad5 | 1157 | instructions containing PC sets in PARALLELs. The instruction may have |
1158 | various other effects so before removing the jump you must verify | |
9641f63c | 1159 | onlyjump_p. |
3a941ad5 | 1160 | |
d670e794 | 1161 | Note that unlike condjump_p it returns false for unconditional jumps. */ |
1162 | ||
3a941ad5 | 1163 | int |
1164 | any_condjump_p (insn) | |
1165 | rtx insn; | |
1166 | { | |
1167 | rtx x = pc_set (insn); | |
d670e794 | 1168 | enum rtx_code a, b; |
1169 | ||
3a941ad5 | 1170 | if (!x) |
1171 | return 0; | |
d670e794 | 1172 | if (GET_CODE (SET_SRC (x)) != IF_THEN_ELSE) |
1173 | return 0; | |
3a941ad5 | 1174 | |
d670e794 | 1175 | a = GET_CODE (XEXP (SET_SRC (x), 1)); |
1176 | b = GET_CODE (XEXP (SET_SRC (x), 2)); | |
3a941ad5 | 1177 | |
d670e794 | 1178 | return ((b == PC && (a == LABEL_REF || a == RETURN)) |
7113a566 | 1179 | || (a == PC && (b == LABEL_REF || b == RETURN))); |
3a941ad5 | 1180 | } |
1181 | ||
8f7b24f3 | 1182 | /* Return the label of a conditional jump. */ |
1183 | ||
1184 | rtx | |
1185 | condjump_label (insn) | |
1186 | rtx insn; | |
1187 | { | |
d670e794 | 1188 | rtx x = pc_set (insn); |
8f7b24f3 | 1189 | |
d670e794 | 1190 | if (!x) |
8f7b24f3 | 1191 | return NULL_RTX; |
1192 | x = SET_SRC (x); | |
1193 | if (GET_CODE (x) == LABEL_REF) | |
1194 | return x; | |
1195 | if (GET_CODE (x) != IF_THEN_ELSE) | |
1196 | return NULL_RTX; | |
1197 | if (XEXP (x, 2) == pc_rtx && GET_CODE (XEXP (x, 1)) == LABEL_REF) | |
1198 | return XEXP (x, 1); | |
1199 | if (XEXP (x, 1) == pc_rtx && GET_CODE (XEXP (x, 2)) == LABEL_REF) | |
1200 | return XEXP (x, 2); | |
1201 | return NULL_RTX; | |
1202 | } | |
1203 | ||
71caadc0 | 1204 | /* Return true if INSN is a (possibly conditional) return insn. */ |
1205 | ||
1206 | static int | |
1207 | returnjump_p_1 (loc, data) | |
1208 | rtx *loc; | |
1209 | void *data ATTRIBUTE_UNUSED; | |
1210 | { | |
1211 | rtx x = *loc; | |
c3987c92 | 1212 | |
1213 | return x && (GET_CODE (x) == RETURN | |
1214 | || (GET_CODE (x) == SET && SET_IS_RETURN_P (x))); | |
71caadc0 | 1215 | } |
1216 | ||
1217 | int | |
1218 | returnjump_p (insn) | |
1219 | rtx insn; | |
1220 | { | |
cbd914e1 | 1221 | if (GET_CODE (insn) != JUMP_INSN) |
1222 | return 0; | |
71caadc0 | 1223 | return for_each_rtx (&PATTERN (insn), returnjump_p_1, NULL); |
1224 | } | |
1225 | ||
459e9193 | 1226 | /* Return true if INSN is a jump that only transfers control and |
1227 | nothing more. */ | |
1228 | ||
1229 | int | |
1230 | onlyjump_p (insn) | |
1231 | rtx insn; | |
1232 | { | |
1233 | rtx set; | |
1234 | ||
1235 | if (GET_CODE (insn) != JUMP_INSN) | |
1236 | return 0; | |
1237 | ||
1238 | set = single_set (insn); | |
1239 | if (set == NULL) | |
1240 | return 0; | |
1241 | if (GET_CODE (SET_DEST (set)) != PC) | |
1242 | return 0; | |
1243 | if (side_effects_p (SET_SRC (set))) | |
1244 | return 0; | |
1245 | ||
1246 | return 1; | |
1247 | } | |
1248 | ||
9bf8c346 | 1249 | #ifdef HAVE_cc0 |
1250 | ||
6ef828f9 | 1251 | /* Return nonzero if X is an RTX that only sets the condition codes |
2dcd83ba | 1252 | and has no side effects. */ |
1253 | ||
1254 | int | |
1255 | only_sets_cc0_p (x) | |
1256 | rtx x; | |
1257 | { | |
1258 | ||
1259 | if (! x) | |
1260 | return 0; | |
1261 | ||
1262 | if (INSN_P (x)) | |
1263 | x = PATTERN (x); | |
1264 | ||
1265 | return sets_cc0_p (x) == 1 && ! side_effects_p (x); | |
1266 | } | |
1267 | ||
5924de0b | 1268 | /* Return 1 if X is an RTX that does nothing but set the condition codes |
1269 | and CLOBBER or USE registers. | |
1270 | Return -1 if X does explicitly set the condition codes, | |
1271 | but also does other things. */ | |
1272 | ||
1273 | int | |
1274 | sets_cc0_p (x) | |
2dcd83ba | 1275 | rtx x; |
5924de0b | 1276 | { |
2dcd83ba | 1277 | |
1278 | if (! x) | |
1279 | return 0; | |
1280 | ||
1281 | if (INSN_P (x)) | |
1282 | x = PATTERN (x); | |
1283 | ||
5924de0b | 1284 | if (GET_CODE (x) == SET && SET_DEST (x) == cc0_rtx) |
1285 | return 1; | |
1286 | if (GET_CODE (x) == PARALLEL) | |
1287 | { | |
1288 | int i; | |
1289 | int sets_cc0 = 0; | |
1290 | int other_things = 0; | |
1291 | for (i = XVECLEN (x, 0) - 1; i >= 0; i--) | |
1292 | { | |
1293 | if (GET_CODE (XVECEXP (x, 0, i)) == SET | |
1294 | && SET_DEST (XVECEXP (x, 0, i)) == cc0_rtx) | |
1295 | sets_cc0 = 1; | |
1296 | else if (GET_CODE (XVECEXP (x, 0, i)) == SET) | |
1297 | other_things = 1; | |
1298 | } | |
1299 | return ! sets_cc0 ? 0 : other_things ? -1 : 1; | |
1300 | } | |
1301 | return 0; | |
5924de0b | 1302 | } |
9bf8c346 | 1303 | #endif |
5924de0b | 1304 | \f |
1305 | /* Follow any unconditional jump at LABEL; | |
1306 | return the ultimate label reached by any such chain of jumps. | |
1307 | If LABEL is not followed by a jump, return LABEL. | |
35e0b416 | 1308 | If the chain loops or we can't find end, return LABEL, |
1309 | since that tells caller to avoid changing the insn. | |
5924de0b | 1310 | |
1311 | If RELOAD_COMPLETED is 0, we do not chain across a NOTE_INSN_LOOP_BEG or | |
1312 | a USE or CLOBBER. */ | |
1313 | ||
1314 | rtx | |
1315 | follow_jumps (label) | |
1316 | rtx label; | |
1317 | { | |
19cb6b50 | 1318 | rtx insn; |
1319 | rtx next; | |
1320 | rtx value = label; | |
1321 | int depth; | |
5924de0b | 1322 | |
1323 | for (depth = 0; | |
1324 | (depth < 10 | |
1325 | && (insn = next_active_insn (value)) != 0 | |
1326 | && GET_CODE (insn) == JUMP_INSN | |
ba08b7e7 | 1327 | && ((JUMP_LABEL (insn) != 0 && any_uncondjump_p (insn) |
1328 | && onlyjump_p (insn)) | |
f93ed41b | 1329 | || GET_CODE (PATTERN (insn)) == RETURN) |
5924de0b | 1330 | && (next = NEXT_INSN (insn)) |
1331 | && GET_CODE (next) == BARRIER); | |
1332 | depth++) | |
1333 | { | |
1334 | /* Don't chain through the insn that jumps into a loop | |
1335 | from outside the loop, | |
1336 | since that would create multiple loop entry jumps | |
1337 | and prevent loop optimization. */ | |
1338 | rtx tem; | |
1339 | if (!reload_completed) | |
1340 | for (tem = value; tem != insn; tem = NEXT_INSN (tem)) | |
1341 | if (GET_CODE (tem) == NOTE | |
55b8f81a | 1342 | && (NOTE_LINE_NUMBER (tem) == NOTE_INSN_LOOP_BEG |
1343 | /* ??? Optional. Disables some optimizations, but makes | |
1344 | gcov output more accurate with -O. */ | |
1345 | || (flag_test_coverage && NOTE_LINE_NUMBER (tem) > 0))) | |
5924de0b | 1346 | return value; |
1347 | ||
1348 | /* If we have found a cycle, make the insn jump to itself. */ | |
1349 | if (JUMP_LABEL (insn) == label) | |
35e0b416 | 1350 | return label; |
cf03b15b | 1351 | |
1352 | tem = next_active_insn (JUMP_LABEL (insn)); | |
1353 | if (tem && (GET_CODE (PATTERN (tem)) == ADDR_VEC | |
1354 | || GET_CODE (PATTERN (tem)) == ADDR_DIFF_VEC)) | |
1355 | break; | |
1356 | ||
5924de0b | 1357 | value = JUMP_LABEL (insn); |
1358 | } | |
35e0b416 | 1359 | if (depth == 10) |
1360 | return label; | |
5924de0b | 1361 | return value; |
1362 | } | |
1363 | ||
5924de0b | 1364 | \f |
1365 | /* Find all CODE_LABELs referred to in X, and increment their use counts. | |
1366 | If INSN is a JUMP_INSN and there is at least one CODE_LABEL referenced | |
1367 | in INSN, then store one of them in JUMP_LABEL (INSN). | |
1368 | If INSN is an INSN or a CALL_INSN and there is at least one CODE_LABEL | |
1369 | referenced in INSN, add a REG_LABEL note containing that label to INSN. | |
1370 | Also, when there are consecutive labels, canonicalize on the last of them. | |
1371 | ||
1372 | Note that two labels separated by a loop-beginning note | |
1373 | must be kept distinct if we have not yet done loop-optimization, | |
1374 | because the gap between them is where loop-optimize | |
1375 | will want to move invariant code to. CROSS_JUMP tells us | |
bf73fcf4 | 1376 | that loop-optimization is done with. */ |
5924de0b | 1377 | |
5377f687 | 1378 | void |
bf73fcf4 | 1379 | mark_jump_label (x, insn, in_mem) |
19cb6b50 | 1380 | rtx x; |
5924de0b | 1381 | rtx insn; |
190099a6 | 1382 | int in_mem; |
5924de0b | 1383 | { |
19cb6b50 | 1384 | RTX_CODE code = GET_CODE (x); |
1385 | int i; | |
1386 | const char *fmt; | |
5924de0b | 1387 | |
1388 | switch (code) | |
1389 | { | |
1390 | case PC: | |
1391 | case CC0: | |
1392 | case REG: | |
5924de0b | 1393 | case CONST_INT: |
5924de0b | 1394 | case CONST_DOUBLE: |
1395 | case CLOBBER: | |
1396 | case CALL: | |
1397 | return; | |
1398 | ||
d8e0d332 | 1399 | case MEM: |
190099a6 | 1400 | in_mem = 1; |
1401 | break; | |
1402 | ||
1403 | case SYMBOL_REF: | |
1404 | if (!in_mem) | |
7113a566 | 1405 | return; |
190099a6 | 1406 | |
d8e0d332 | 1407 | /* If this is a constant-pool reference, see if it is a label. */ |
190099a6 | 1408 | if (CONSTANT_POOL_ADDRESS_P (x)) |
bf73fcf4 | 1409 | mark_jump_label (get_pool_constant (x), insn, in_mem); |
d8e0d332 | 1410 | break; |
1411 | ||
5924de0b | 1412 | case LABEL_REF: |
1413 | { | |
b4d3bcce | 1414 | rtx label = XEXP (x, 0); |
b4d3bcce | 1415 | |
74b0991d | 1416 | /* Ignore remaining references to unreachable labels that |
1417 | have been deleted. */ | |
7113a566 | 1418 | if (GET_CODE (label) == NOTE |
74b0991d | 1419 | && NOTE_LINE_NUMBER (label) == NOTE_INSN_DELETED_LABEL) |
1420 | break; | |
1421 | ||
5924de0b | 1422 | if (GET_CODE (label) != CODE_LABEL) |
1423 | abort (); | |
b4d3bcce | 1424 | |
f08cae9d | 1425 | /* Ignore references to labels of containing functions. */ |
1426 | if (LABEL_REF_NONLOCAL_P (x)) | |
1427 | break; | |
b4d3bcce | 1428 | |
5924de0b | 1429 | XEXP (x, 0) = label; |
943e16d8 | 1430 | if (! insn || ! INSN_DELETED_P (insn)) |
1431 | ++LABEL_NUSES (label); | |
b4d3bcce | 1432 | |
5924de0b | 1433 | if (insn) |
1434 | { | |
1435 | if (GET_CODE (insn) == JUMP_INSN) | |
1436 | JUMP_LABEL (insn) = label; | |
ab2237b5 | 1437 | else |
e89849bd | 1438 | { |
ab2237b5 | 1439 | /* Add a REG_LABEL note for LABEL unless there already |
1440 | is one. All uses of a label, except for labels | |
1441 | that are the targets of jumps, must have a | |
1442 | REG_LABEL note. */ | |
1443 | if (! find_reg_note (insn, REG_LABEL, label)) | |
60d9e0ee | 1444 | REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, label, |
ab2237b5 | 1445 | REG_NOTES (insn)); |
5924de0b | 1446 | } |
1447 | } | |
1448 | return; | |
1449 | } | |
1450 | ||
1451 | /* Do walk the labels in a vector, but not the first operand of an | |
1452 | ADDR_DIFF_VEC. Don't set the JUMP_LABEL of a vector. */ | |
1453 | case ADDR_VEC: | |
1454 | case ADDR_DIFF_VEC: | |
943e16d8 | 1455 | if (! INSN_DELETED_P (insn)) |
1456 | { | |
1457 | int eltnum = code == ADDR_DIFF_VEC ? 1 : 0; | |
5924de0b | 1458 | |
943e16d8 | 1459 | for (i = 0; i < XVECLEN (x, eltnum); i++) |
bf73fcf4 | 1460 | mark_jump_label (XVECEXP (x, eltnum, i), NULL_RTX, in_mem); |
943e16d8 | 1461 | } |
0dbd1c74 | 1462 | return; |
7113a566 | 1463 | |
0dbd1c74 | 1464 | default: |
1465 | break; | |
5924de0b | 1466 | } |
1467 | ||
1468 | fmt = GET_RTX_FORMAT (code); | |
1469 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1470 | { | |
1471 | if (fmt[i] == 'e') | |
bf73fcf4 | 1472 | mark_jump_label (XEXP (x, i), insn, in_mem); |
5924de0b | 1473 | else if (fmt[i] == 'E') |
1474 | { | |
19cb6b50 | 1475 | int j; |
5924de0b | 1476 | for (j = 0; j < XVECLEN (x, i); j++) |
bf73fcf4 | 1477 | mark_jump_label (XVECEXP (x, i, j), insn, in_mem); |
5924de0b | 1478 | } |
1479 | } | |
1480 | } | |
1481 | ||
1482 | /* If all INSN does is set the pc, delete it, | |
1483 | and delete the insn that set the condition codes for it | |
1484 | if that's what the previous thing was. */ | |
1485 | ||
1486 | void | |
1487 | delete_jump (insn) | |
1488 | rtx insn; | |
1489 | { | |
19cb6b50 | 1490 | rtx set = single_set (insn); |
f4ef05ab | 1491 | |
1492 | if (set && GET_CODE (SET_DEST (set)) == PC) | |
1493 | delete_computation (insn); | |
1494 | } | |
1495 | ||
155b05dc | 1496 | /* Verify INSN is a BARRIER and delete it. */ |
1497 | ||
1498 | void | |
1499 | delete_barrier (insn) | |
1500 | rtx insn; | |
1501 | { | |
1502 | if (GET_CODE (insn) != BARRIER) | |
1503 | abort (); | |
1504 | ||
1505 | delete_insn (insn); | |
1506 | } | |
1507 | ||
ab1241f2 | 1508 | /* Recursively delete prior insns that compute the value (used only by INSN |
1509 | which the caller is deleting) stored in the register mentioned by NOTE | |
1510 | which is a REG_DEAD note associated with INSN. */ | |
1511 | ||
1512 | static void | |
1513 | delete_prior_computation (note, insn) | |
1514 | rtx note; | |
1515 | rtx insn; | |
1516 | { | |
1517 | rtx our_prev; | |
1518 | rtx reg = XEXP (note, 0); | |
1519 | ||
1520 | for (our_prev = prev_nonnote_insn (insn); | |
272a2170 | 1521 | our_prev && (GET_CODE (our_prev) == INSN |
1522 | || GET_CODE (our_prev) == CALL_INSN); | |
ab1241f2 | 1523 | our_prev = prev_nonnote_insn (our_prev)) |
1524 | { | |
1525 | rtx pat = PATTERN (our_prev); | |
1526 | ||
272a2170 | 1527 | /* If we reach a CALL which is not calling a const function |
1528 | or the callee pops the arguments, then give up. */ | |
1529 | if (GET_CODE (our_prev) == CALL_INSN | |
06a652d1 | 1530 | && (! CONST_OR_PURE_CALL_P (our_prev) |
272a2170 | 1531 | || GET_CODE (pat) != SET || GET_CODE (SET_SRC (pat)) != CALL)) |
1532 | break; | |
1533 | ||
ab1241f2 | 1534 | /* If we reach a SEQUENCE, it is too complex to try to |
31d3e01c | 1535 | do anything with it, so give up. We can be run during |
1536 | and after reorg, so SEQUENCE rtl can legitimately show | |
1537 | up here. */ | |
ab1241f2 | 1538 | if (GET_CODE (pat) == SEQUENCE) |
1539 | break; | |
1540 | ||
1541 | if (GET_CODE (pat) == USE | |
1542 | && GET_CODE (XEXP (pat, 0)) == INSN) | |
1543 | /* reorg creates USEs that look like this. We leave them | |
1544 | alone because reorg needs them for its own purposes. */ | |
1545 | break; | |
1546 | ||
1547 | if (reg_set_p (reg, pat)) | |
1548 | { | |
272a2170 | 1549 | if (side_effects_p (pat) && GET_CODE (our_prev) != CALL_INSN) |
ab1241f2 | 1550 | break; |
1551 | ||
1552 | if (GET_CODE (pat) == PARALLEL) | |
1553 | { | |
1554 | /* If we find a SET of something else, we can't | |
1555 | delete the insn. */ | |
1556 | ||
1557 | int i; | |
1558 | ||
1559 | for (i = 0; i < XVECLEN (pat, 0); i++) | |
1560 | { | |
1561 | rtx part = XVECEXP (pat, 0, i); | |
1562 | ||
1563 | if (GET_CODE (part) == SET | |
1564 | && SET_DEST (part) != reg) | |
1565 | break; | |
1566 | } | |
1567 | ||
1568 | if (i == XVECLEN (pat, 0)) | |
1569 | delete_computation (our_prev); | |
1570 | } | |
1571 | else if (GET_CODE (pat) == SET | |
1572 | && GET_CODE (SET_DEST (pat)) == REG) | |
1573 | { | |
1574 | int dest_regno = REGNO (SET_DEST (pat)); | |
1575 | int dest_endregno | |
7113a566 | 1576 | = (dest_regno |
1577 | + (dest_regno < FIRST_PSEUDO_REGISTER | |
ab1241f2 | 1578 | ? HARD_REGNO_NREGS (dest_regno, |
7113a566 | 1579 | GET_MODE (SET_DEST (pat))) : 1)); |
ab1241f2 | 1580 | int regno = REGNO (reg); |
7113a566 | 1581 | int endregno |
1582 | = (regno | |
1583 | + (regno < FIRST_PSEUDO_REGISTER | |
1584 | ? HARD_REGNO_NREGS (regno, GET_MODE (reg)) : 1)); | |
ab1241f2 | 1585 | |
1586 | if (dest_regno >= regno | |
1587 | && dest_endregno <= endregno) | |
1588 | delete_computation (our_prev); | |
1589 | ||
1590 | /* We may have a multi-word hard register and some, but not | |
1591 | all, of the words of the register are needed in subsequent | |
1592 | insns. Write REG_UNUSED notes for those parts that were not | |
1593 | needed. */ | |
1594 | else if (dest_regno <= regno | |
272a2170 | 1595 | && dest_endregno >= endregno) |
ab1241f2 | 1596 | { |
1597 | int i; | |
1598 | ||
1599 | REG_NOTES (our_prev) | |
7113a566 | 1600 | = gen_rtx_EXPR_LIST (REG_UNUSED, reg, |
1601 | REG_NOTES (our_prev)); | |
ab1241f2 | 1602 | |
1603 | for (i = dest_regno; i < dest_endregno; i++) | |
1604 | if (! find_regno_note (our_prev, REG_UNUSED, i)) | |
1605 | break; | |
1606 | ||
1607 | if (i == dest_endregno) | |
1608 | delete_computation (our_prev); | |
1609 | } | |
1610 | } | |
1611 | ||
1612 | break; | |
1613 | } | |
1614 | ||
1615 | /* If PAT references the register that dies here, it is an | |
1616 | additional use. Hence any prior SET isn't dead. However, this | |
1617 | insn becomes the new place for the REG_DEAD note. */ | |
1618 | if (reg_overlap_mentioned_p (reg, pat)) | |
1619 | { | |
1620 | XEXP (note, 1) = REG_NOTES (our_prev); | |
1621 | REG_NOTES (our_prev) = note; | |
1622 | break; | |
1623 | } | |
1624 | } | |
1625 | } | |
1626 | ||
f4ef05ab | 1627 | /* Delete INSN and recursively delete insns that compute values used only |
1628 | by INSN. This uses the REG_DEAD notes computed during flow analysis. | |
1629 | If we are running before flow.c, we need do nothing since flow.c will | |
1630 | delete dead code. We also can't know if the registers being used are | |
1631 | dead or not at this point. | |
1632 | ||
1633 | Otherwise, look at all our REG_DEAD notes. If a previous insn does | |
1634 | nothing other than set a register that dies in this insn, we can delete | |
1635 | that insn as well. | |
1636 | ||
1637 | On machines with CC0, if CC0 is used in this insn, we may be able to | |
1638 | delete the insn that set it. */ | |
1639 | ||
fb374064 | 1640 | static void |
f4ef05ab | 1641 | delete_computation (insn) |
1642 | rtx insn; | |
1643 | { | |
1644 | rtx note, next; | |
5924de0b | 1645 | |
5924de0b | 1646 | #ifdef HAVE_cc0 |
41d75671 | 1647 | if (reg_referenced_p (cc0_rtx, PATTERN (insn))) |
f4ef05ab | 1648 | { |
5b39732e | 1649 | rtx prev = prev_nonnote_insn (insn); |
5924de0b | 1650 | /* We assume that at this stage |
1651 | CC's are always set explicitly | |
1652 | and always immediately before the jump that | |
1653 | will use them. So if the previous insn | |
1654 | exists to set the CC's, delete it | |
1655 | (unless it performs auto-increments, etc.). */ | |
1656 | if (prev && GET_CODE (prev) == INSN | |
1657 | && sets_cc0_p (PATTERN (prev))) | |
1658 | { | |
1659 | if (sets_cc0_p (PATTERN (prev)) > 0 | |
ab1241f2 | 1660 | && ! side_effects_p (PATTERN (prev))) |
f4ef05ab | 1661 | delete_computation (prev); |
5924de0b | 1662 | else |
1663 | /* Otherwise, show that cc0 won't be used. */ | |
941522d6 | 1664 | REG_NOTES (prev) = gen_rtx_EXPR_LIST (REG_UNUSED, |
1665 | cc0_rtx, REG_NOTES (prev)); | |
5924de0b | 1666 | } |
5b39732e | 1667 | } |
f4ef05ab | 1668 | #endif |
5924de0b | 1669 | |
5b39732e | 1670 | for (note = REG_NOTES (insn); note; note = next) |
1671 | { | |
5b39732e | 1672 | next = XEXP (note, 1); |
5924de0b | 1673 | |
5b39732e | 1674 | if (REG_NOTE_KIND (note) != REG_DEAD |
1675 | /* Verify that the REG_NOTE is legitimate. */ | |
1676 | || GET_CODE (XEXP (note, 0)) != REG) | |
1677 | continue; | |
5924de0b | 1678 | |
ab1241f2 | 1679 | delete_prior_computation (note, insn); |
5924de0b | 1680 | } |
f4ef05ab | 1681 | |
e4bf866d | 1682 | delete_related_insns (insn); |
5924de0b | 1683 | } |
1684 | \f | |
e4bf866d | 1685 | /* Delete insn INSN from the chain of insns and update label ref counts |
1686 | and delete insns now unreachable. | |
1687 | ||
1688 | Returns the first insn after INSN that was not deleted. | |
5924de0b | 1689 | |
e4bf866d | 1690 | Usage of this instruction is deprecated. Use delete_insn instead and |
1691 | subsequent cfg_cleanup pass to delete unreachable code if needed. */ | |
5924de0b | 1692 | |
1693 | rtx | |
e4bf866d | 1694 | delete_related_insns (insn) |
19cb6b50 | 1695 | rtx insn; |
5924de0b | 1696 | { |
19cb6b50 | 1697 | int was_code_label = (GET_CODE (insn) == CODE_LABEL); |
d3df77e9 | 1698 | rtx note; |
e4bf866d | 1699 | rtx next = NEXT_INSN (insn), prev = PREV_INSN (insn); |
5924de0b | 1700 | |
1701 | while (next && INSN_DELETED_P (next)) | |
1702 | next = NEXT_INSN (next); | |
1703 | ||
1704 | /* This insn is already deleted => return first following nondeleted. */ | |
1705 | if (INSN_DELETED_P (insn)) | |
1706 | return next; | |
1707 | ||
e4bf866d | 1708 | delete_insn (insn); |
5924de0b | 1709 | |
5924de0b | 1710 | /* If instruction is followed by a barrier, |
1711 | delete the barrier too. */ | |
1712 | ||
1713 | if (next != 0 && GET_CODE (next) == BARRIER) | |
e4bf866d | 1714 | delete_insn (next); |
5924de0b | 1715 | |
1716 | /* If deleting a jump, decrement the count of the label, | |
1717 | and delete the label if it is now unused. */ | |
1718 | ||
1719 | if (GET_CODE (insn) == JUMP_INSN && JUMP_LABEL (insn)) | |
1793cd6b | 1720 | { |
1721 | rtx lab = JUMP_LABEL (insn), lab_next; | |
1722 | ||
e4bf866d | 1723 | if (LABEL_NUSES (lab) == 0) |
1793cd6b | 1724 | { |
1725 | /* This can delete NEXT or PREV, | |
1726 | either directly if NEXT is JUMP_LABEL (INSN), | |
1727 | or indirectly through more levels of jumps. */ | |
e4bf866d | 1728 | delete_related_insns (lab); |
1793cd6b | 1729 | |
1730 | /* I feel a little doubtful about this loop, | |
1731 | but I see no clean and sure alternative way | |
1732 | to find the first insn after INSN that is not now deleted. | |
1733 | I hope this works. */ | |
1734 | while (next && INSN_DELETED_P (next)) | |
1735 | next = NEXT_INSN (next); | |
1736 | return next; | |
1737 | } | |
1738 | else if ((lab_next = next_nonnote_insn (lab)) != NULL | |
1739 | && GET_CODE (lab_next) == JUMP_INSN | |
1740 | && (GET_CODE (PATTERN (lab_next)) == ADDR_VEC | |
1741 | || GET_CODE (PATTERN (lab_next)) == ADDR_DIFF_VEC)) | |
1742 | { | |
1743 | /* If we're deleting the tablejump, delete the dispatch table. | |
4a82352a | 1744 | We may not be able to kill the label immediately preceding |
1793cd6b | 1745 | just yet, as it might be referenced in code leading up to |
1746 | the tablejump. */ | |
e4bf866d | 1747 | delete_related_insns (lab_next); |
1793cd6b | 1748 | } |
1749 | } | |
5924de0b | 1750 | |
9c9e0c01 | 1751 | /* Likewise if we're deleting a dispatch table. */ |
1752 | ||
1753 | if (GET_CODE (insn) == JUMP_INSN | |
1754 | && (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
1755 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)) | |
1756 | { | |
1757 | rtx pat = PATTERN (insn); | |
1758 | int i, diff_vec_p = GET_CODE (pat) == ADDR_DIFF_VEC; | |
1759 | int len = XVECLEN (pat, diff_vec_p); | |
1760 | ||
1761 | for (i = 0; i < len; i++) | |
e4bf866d | 1762 | if (LABEL_NUSES (XEXP (XVECEXP (pat, diff_vec_p, i), 0)) == 0) |
1763 | delete_related_insns (XEXP (XVECEXP (pat, diff_vec_p, i), 0)); | |
9c9e0c01 | 1764 | while (next && INSN_DELETED_P (next)) |
1765 | next = NEXT_INSN (next); | |
1766 | return next; | |
1767 | } | |
1768 | ||
d3df77e9 | 1769 | /* Likewise for an ordinary INSN / CALL_INSN with a REG_LABEL note. */ |
1770 | if (GET_CODE (insn) == INSN || GET_CODE (insn) == CALL_INSN) | |
1771 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) | |
0c97f529 | 1772 | if (REG_NOTE_KIND (note) == REG_LABEL |
1773 | /* This could also be a NOTE_INSN_DELETED_LABEL note. */ | |
1774 | && GET_CODE (XEXP (note, 0)) == CODE_LABEL) | |
e4bf866d | 1775 | if (LABEL_NUSES (XEXP (note, 0)) == 0) |
1776 | delete_related_insns (XEXP (note, 0)); | |
d3df77e9 | 1777 | |
5924de0b | 1778 | while (prev && (INSN_DELETED_P (prev) || GET_CODE (prev) == NOTE)) |
1779 | prev = PREV_INSN (prev); | |
1780 | ||
1781 | /* If INSN was a label and a dispatch table follows it, | |
1782 | delete the dispatch table. The tablejump must have gone already. | |
1783 | It isn't useful to fall through into a table. */ | |
1784 | ||
9cdc08c6 | 1785 | if (was_code_label |
5924de0b | 1786 | && NEXT_INSN (insn) != 0 |
1787 | && GET_CODE (NEXT_INSN (insn)) == JUMP_INSN | |
1788 | && (GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_VEC | |
1789 | || GET_CODE (PATTERN (NEXT_INSN (insn))) == ADDR_DIFF_VEC)) | |
e4bf866d | 1790 | next = delete_related_insns (NEXT_INSN (insn)); |
5924de0b | 1791 | |
1792 | /* If INSN was a label, delete insns following it if now unreachable. */ | |
1793 | ||
9cdc08c6 | 1794 | if (was_code_label && prev && GET_CODE (prev) == BARRIER) |
5924de0b | 1795 | { |
19cb6b50 | 1796 | RTX_CODE code; |
5924de0b | 1797 | while (next != 0 |
fb374064 | 1798 | && (GET_RTX_CLASS (code = GET_CODE (next)) == 'i' |
64f0b11f | 1799 | || code == NOTE || code == BARRIER |
59bee35e | 1800 | || (code == CODE_LABEL && INSN_DELETED_P (next)))) |
5924de0b | 1801 | { |
1802 | if (code == NOTE | |
1803 | && NOTE_LINE_NUMBER (next) != NOTE_INSN_FUNCTION_END) | |
1804 | next = NEXT_INSN (next); | |
59bee35e | 1805 | /* Keep going past other deleted labels to delete what follows. */ |
1806 | else if (code == CODE_LABEL && INSN_DELETED_P (next)) | |
1807 | next = NEXT_INSN (next); | |
5924de0b | 1808 | else |
1809 | /* Note: if this deletes a jump, it can cause more | |
1810 | deletion of unreachable code, after a different label. | |
1811 | As long as the value from this recursive call is correct, | |
1812 | this invocation functions correctly. */ | |
e4bf866d | 1813 | next = delete_related_insns (next); |
5924de0b | 1814 | } |
1815 | } | |
1816 | ||
1817 | return next; | |
1818 | } | |
1819 | ||
1820 | /* Advance from INSN till reaching something not deleted | |
1821 | then return that. May return INSN itself. */ | |
1822 | ||
1823 | rtx | |
1824 | next_nondeleted_insn (insn) | |
1825 | rtx insn; | |
1826 | { | |
1827 | while (INSN_DELETED_P (insn)) | |
1828 | insn = NEXT_INSN (insn); | |
1829 | return insn; | |
1830 | } | |
1831 | \f | |
1832 | /* Delete a range of insns from FROM to TO, inclusive. | |
1833 | This is for the sake of peephole optimization, so assume | |
1834 | that whatever these insns do will still be done by a new | |
1835 | peephole insn that will replace them. */ | |
1836 | ||
1837 | void | |
1838 | delete_for_peephole (from, to) | |
19cb6b50 | 1839 | rtx from, to; |
5924de0b | 1840 | { |
19cb6b50 | 1841 | rtx insn = from; |
5924de0b | 1842 | |
1843 | while (1) | |
1844 | { | |
19cb6b50 | 1845 | rtx next = NEXT_INSN (insn); |
1846 | rtx prev = PREV_INSN (insn); | |
5924de0b | 1847 | |
1848 | if (GET_CODE (insn) != NOTE) | |
1849 | { | |
1850 | INSN_DELETED_P (insn) = 1; | |
1851 | ||
1852 | /* Patch this insn out of the chain. */ | |
1853 | /* We don't do this all at once, because we | |
1854 | must preserve all NOTEs. */ | |
1855 | if (prev) | |
1856 | NEXT_INSN (prev) = next; | |
1857 | ||
1858 | if (next) | |
1859 | PREV_INSN (next) = prev; | |
1860 | } | |
1861 | ||
1862 | if (insn == to) | |
1863 | break; | |
1864 | insn = next; | |
1865 | } | |
1866 | ||
1867 | /* Note that if TO is an unconditional jump | |
1868 | we *do not* delete the BARRIER that follows, | |
1869 | since the peephole that replaces this sequence | |
1870 | is also an unconditional jump in that case. */ | |
1871 | } | |
1872 | \f | |
71a3455a | 1873 | /* We have determined that INSN is never reached, and are about to |
1874 | delete it. Print a warning if the user asked for one. | |
1875 | ||
1876 | To try to make this warning more useful, this should only be called | |
1877 | once per basic block not reached, and it only warns when the basic | |
1878 | block contains more than one line from the current function, and | |
1879 | contains at least one operation. CSE and inlining can duplicate insns, | |
1880 | so it's possible to get spurious warnings from this. */ | |
1881 | ||
1882 | void | |
5b154f04 | 1883 | never_reached_warning (avoided_insn, finish) |
1884 | rtx avoided_insn, finish; | |
71a3455a | 1885 | { |
1886 | rtx insn; | |
1887 | rtx a_line_note = NULL; | |
5b154f04 | 1888 | int two_avoided_lines = 0, contains_insn = 0, reached_end = 0; |
7113a566 | 1889 | |
71a3455a | 1890 | if (! warn_notreached) |
1891 | return; | |
1892 | ||
1893 | /* Scan forwards, looking at LINE_NUMBER notes, until | |
1894 | we hit a LABEL or we run out of insns. */ | |
7113a566 | 1895 | |
71a3455a | 1896 | for (insn = avoided_insn; insn != NULL; insn = NEXT_INSN (insn)) |
1897 | { | |
5b154f04 | 1898 | if (finish == NULL && GET_CODE (insn) == CODE_LABEL) |
7113a566 | 1899 | break; |
5b154f04 | 1900 | |
1901 | if (GET_CODE (insn) == NOTE /* A line number note? */ | |
1902 | && NOTE_LINE_NUMBER (insn) >= 0) | |
71a3455a | 1903 | { |
1904 | if (a_line_note == NULL) | |
1905 | a_line_note = insn; | |
1906 | else | |
1907 | two_avoided_lines |= (NOTE_LINE_NUMBER (a_line_note) | |
1908 | != NOTE_LINE_NUMBER (insn)); | |
1909 | } | |
9204e736 | 1910 | else if (INSN_P (insn)) |
5b154f04 | 1911 | { |
db15c0db | 1912 | if (reached_end || a_line_note == NULL) |
5b154f04 | 1913 | break; |
1914 | contains_insn = 1; | |
1915 | } | |
1916 | ||
1917 | if (insn == finish) | |
1918 | reached_end = 1; | |
71a3455a | 1919 | } |
1920 | if (two_avoided_lines && contains_insn) | |
1921 | warning_with_file_and_line (NOTE_SOURCE_FILE (a_line_note), | |
1922 | NOTE_LINE_NUMBER (a_line_note), | |
1923 | "will never be executed"); | |
1924 | } | |
1925 | \f | |
a8b5d014 | 1926 | /* Throughout LOC, redirect OLABEL to NLABEL. Treat null OLABEL or |
1927 | NLABEL as a return. Accrue modifications into the change group. */ | |
5924de0b | 1928 | |
a8b5d014 | 1929 | static void |
1930 | redirect_exp_1 (loc, olabel, nlabel, insn) | |
1931 | rtx *loc; | |
1932 | rtx olabel, nlabel; | |
5924de0b | 1933 | rtx insn; |
1934 | { | |
19cb6b50 | 1935 | rtx x = *loc; |
1936 | RTX_CODE code = GET_CODE (x); | |
1937 | int i; | |
1938 | const char *fmt; | |
5924de0b | 1939 | |
a8b5d014 | 1940 | if (code == LABEL_REF) |
5924de0b | 1941 | { |
a8b5d014 | 1942 | if (XEXP (x, 0) == olabel) |
1943 | { | |
1944 | rtx n; | |
1945 | if (nlabel) | |
1946 | n = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1947 | else | |
7113a566 | 1948 | n = gen_rtx_RETURN (VOIDmode); |
5924de0b | 1949 | |
a8b5d014 | 1950 | validate_change (insn, loc, n, 1); |
1951 | return; | |
1952 | } | |
1953 | } | |
1954 | else if (code == RETURN && olabel == 0) | |
1955 | { | |
1956 | x = gen_rtx_LABEL_REF (VOIDmode, nlabel); | |
1957 | if (loc == &PATTERN (insn)) | |
1958 | x = gen_rtx_SET (VOIDmode, pc_rtx, x); | |
1959 | validate_change (insn, loc, x, 1); | |
1960 | return; | |
1961 | } | |
5924de0b | 1962 | |
a8b5d014 | 1963 | if (code == SET && nlabel == 0 && SET_DEST (x) == pc_rtx |
1964 | && GET_CODE (SET_SRC (x)) == LABEL_REF | |
1965 | && XEXP (SET_SRC (x), 0) == olabel) | |
1966 | { | |
1967 | validate_change (insn, loc, gen_rtx_RETURN (VOIDmode), 1); | |
1968 | return; | |
5924de0b | 1969 | } |
1970 | ||
1971 | fmt = GET_RTX_FORMAT (code); | |
1972 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1973 | { | |
1974 | if (fmt[i] == 'e') | |
a8b5d014 | 1975 | redirect_exp_1 (&XEXP (x, i), olabel, nlabel, insn); |
1bd8ca86 | 1976 | else if (fmt[i] == 'E') |
5924de0b | 1977 | { |
19cb6b50 | 1978 | int j; |
5924de0b | 1979 | for (j = 0; j < XVECLEN (x, i); j++) |
a8b5d014 | 1980 | redirect_exp_1 (&XVECEXP (x, i, j), olabel, nlabel, insn); |
5924de0b | 1981 | } |
1982 | } | |
a8b5d014 | 1983 | } |
5924de0b | 1984 | |
a8b5d014 | 1985 | /* Similar, but apply the change group and report success or failure. */ |
1986 | ||
ba08b7e7 | 1987 | static int |
1988 | redirect_exp (olabel, nlabel, insn) | |
a8b5d014 | 1989 | rtx olabel, nlabel; |
1990 | rtx insn; | |
1991 | { | |
ba08b7e7 | 1992 | rtx *loc; |
1993 | ||
1994 | if (GET_CODE (PATTERN (insn)) == PARALLEL) | |
1995 | loc = &XVECEXP (PATTERN (insn), 0, 0); | |
1996 | else | |
1997 | loc = &PATTERN (insn); | |
1998 | ||
a8b5d014 | 1999 | redirect_exp_1 (loc, olabel, nlabel, insn); |
2000 | if (num_validated_changes () == 0) | |
2001 | return 0; | |
2002 | ||
2003 | return apply_change_group (); | |
5924de0b | 2004 | } |
a8b5d014 | 2005 | |
2006 | /* Make JUMP go to NLABEL instead of where it jumps now. Accrue | |
2007 | the modifications into the change group. Return false if we did | |
2008 | not see how to do that. */ | |
2009 | ||
2010 | int | |
2011 | redirect_jump_1 (jump, nlabel) | |
2012 | rtx jump, nlabel; | |
2013 | { | |
2014 | int ochanges = num_validated_changes (); | |
ba08b7e7 | 2015 | rtx *loc; |
2016 | ||
2017 | if (GET_CODE (PATTERN (jump)) == PARALLEL) | |
2018 | loc = &XVECEXP (PATTERN (jump), 0, 0); | |
2019 | else | |
2020 | loc = &PATTERN (jump); | |
2021 | ||
2022 | redirect_exp_1 (loc, JUMP_LABEL (jump), nlabel, jump); | |
a8b5d014 | 2023 | return num_validated_changes () > ochanges; |
2024 | } | |
2025 | ||
2026 | /* Make JUMP go to NLABEL instead of where it jumps now. If the old | |
2027 | jump target label is unused as a result, it and the code following | |
2028 | it may be deleted. | |
5924de0b | 2029 | |
2030 | If NLABEL is zero, we are to turn the jump into a (possibly conditional) | |
2031 | RETURN insn. | |
2032 | ||
a8b5d014 | 2033 | The return value will be 1 if the change was made, 0 if it wasn't |
2034 | (this can only occur for NLABEL == 0). */ | |
5924de0b | 2035 | |
2036 | int | |
f8cacb57 | 2037 | redirect_jump (jump, nlabel, delete_unused) |
5924de0b | 2038 | rtx jump, nlabel; |
f8cacb57 | 2039 | int delete_unused; |
5924de0b | 2040 | { |
19cb6b50 | 2041 | rtx olabel = JUMP_LABEL (jump); |
5924de0b | 2042 | |
2043 | if (nlabel == olabel) | |
2044 | return 1; | |
2045 | ||
ba08b7e7 | 2046 | if (! redirect_exp (olabel, nlabel, jump)) |
5924de0b | 2047 | return 0; |
2048 | ||
5924de0b | 2049 | JUMP_LABEL (jump) = nlabel; |
2050 | if (nlabel) | |
2051 | ++LABEL_NUSES (nlabel); | |
2052 | ||
9cf49039 | 2053 | /* If we're eliding the jump over exception cleanups at the end of a |
2054 | function, move the function end note so that -Wreturn-type works. */ | |
4476207f | 2055 | if (olabel && nlabel |
2056 | && NEXT_INSN (olabel) | |
9cf49039 | 2057 | && GET_CODE (NEXT_INSN (olabel)) == NOTE |
2058 | && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END) | |
2059 | emit_note_after (NOTE_INSN_FUNCTION_END, nlabel); | |
2060 | ||
7f8c3466 | 2061 | if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused |
2062 | /* Undefined labels will remain outside the insn stream. */ | |
2063 | && INSN_UID (olabel)) | |
e4bf866d | 2064 | delete_related_insns (olabel); |
5924de0b | 2065 | |
2066 | return 1; | |
2067 | } | |
2068 | ||
7113a566 | 2069 | /* Invert the jump condition of rtx X contained in jump insn, INSN. |
a8b5d014 | 2070 | Accrue the modifications into the change group. */ |
2071 | ||
2072 | static void | |
ba08b7e7 | 2073 | invert_exp_1 (insn) |
a8b5d014 | 2074 | rtx insn; |
2075 | { | |
19cb6b50 | 2076 | RTX_CODE code; |
ba08b7e7 | 2077 | rtx x = pc_set (insn); |
2078 | ||
2079 | if (!x) | |
7113a566 | 2080 | abort (); |
ba08b7e7 | 2081 | x = SET_SRC (x); |
a8b5d014 | 2082 | |
2083 | code = GET_CODE (x); | |
2084 | ||
2085 | if (code == IF_THEN_ELSE) | |
2086 | { | |
19cb6b50 | 2087 | rtx comp = XEXP (x, 0); |
2088 | rtx tem; | |
7da6ea0c | 2089 | enum rtx_code reversed_code; |
a8b5d014 | 2090 | |
2091 | /* We can do this in two ways: The preferable way, which can only | |
2092 | be done if this is not an integer comparison, is to reverse | |
2093 | the comparison code. Otherwise, swap the THEN-part and ELSE-part | |
2094 | of the IF_THEN_ELSE. If we can't do either, fail. */ | |
2095 | ||
7da6ea0c | 2096 | reversed_code = reversed_comparison_code (comp, insn); |
2097 | ||
2098 | if (reversed_code != UNKNOWN) | |
a8b5d014 | 2099 | { |
2100 | validate_change (insn, &XEXP (x, 0), | |
7da6ea0c | 2101 | gen_rtx_fmt_ee (reversed_code, |
a8b5d014 | 2102 | GET_MODE (comp), XEXP (comp, 0), |
2103 | XEXP (comp, 1)), | |
2104 | 1); | |
2105 | return; | |
2106 | } | |
7113a566 | 2107 | |
a8b5d014 | 2108 | tem = XEXP (x, 1); |
2109 | validate_change (insn, &XEXP (x, 1), XEXP (x, 2), 1); | |
2110 | validate_change (insn, &XEXP (x, 2), tem, 1); | |
a8b5d014 | 2111 | } |
ba08b7e7 | 2112 | else |
2113 | abort (); | |
a8b5d014 | 2114 | } |
2115 | ||
7113a566 | 2116 | /* Invert the jump condition of conditional jump insn, INSN. |
a8b5d014 | 2117 | |
2118 | Return 1 if we can do so, 0 if we cannot find a way to do so that | |
2119 | matches a pattern. */ | |
2120 | ||
ba08b7e7 | 2121 | static int |
2122 | invert_exp (insn) | |
a8b5d014 | 2123 | rtx insn; |
2124 | { | |
ba08b7e7 | 2125 | invert_exp_1 (insn); |
a8b5d014 | 2126 | if (num_validated_changes () == 0) |
2127 | return 0; | |
2128 | ||
2129 | return apply_change_group (); | |
2130 | } | |
2131 | ||
2132 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2133 | NLABEL instead of where it jumps now. Accrue changes into the | |
2134 | change group. Return false if we didn't see how to perform the | |
2135 | inversion and redirection. */ | |
2136 | ||
2137 | int | |
2138 | invert_jump_1 (jump, nlabel) | |
2139 | rtx jump, nlabel; | |
2140 | { | |
2141 | int ochanges; | |
2142 | ||
2143 | ochanges = num_validated_changes (); | |
ba08b7e7 | 2144 | invert_exp_1 (jump); |
a8b5d014 | 2145 | if (num_validated_changes () == ochanges) |
2146 | return 0; | |
2147 | ||
2148 | return redirect_jump_1 (jump, nlabel); | |
2149 | } | |
2150 | ||
2151 | /* Invert the condition of the jump JUMP, and make it jump to label | |
2152 | NLABEL instead of where it jumps now. Return true if successful. */ | |
2153 | ||
2154 | int | |
f8cacb57 | 2155 | invert_jump (jump, nlabel, delete_unused) |
a8b5d014 | 2156 | rtx jump, nlabel; |
f8cacb57 | 2157 | int delete_unused; |
a8b5d014 | 2158 | { |
2159 | /* We have to either invert the condition and change the label or | |
2160 | do neither. Either operation could fail. We first try to invert | |
2161 | the jump. If that succeeds, we try changing the label. If that fails, | |
2162 | we invert the jump back to what it was. */ | |
2163 | ||
ba08b7e7 | 2164 | if (! invert_exp (jump)) |
a8b5d014 | 2165 | return 0; |
2166 | ||
f8cacb57 | 2167 | if (redirect_jump (jump, nlabel, delete_unused)) |
a8b5d014 | 2168 | { |
13488c51 | 2169 | invert_br_probabilities (jump); |
a8b5d014 | 2170 | |
2171 | return 1; | |
2172 | } | |
2173 | ||
ba08b7e7 | 2174 | if (! invert_exp (jump)) |
a8b5d014 | 2175 | /* This should just be putting it back the way it was. */ |
2176 | abort (); | |
2177 | ||
2178 | return 0; | |
2179 | } | |
2180 | ||
5924de0b | 2181 | \f |
2182 | /* Like rtx_equal_p except that it considers two REGs as equal | |
6c60c295 | 2183 | if they renumber to the same value and considers two commutative |
2184 | operations to be the same if the order of the operands has been | |
2207ad6a | 2185 | reversed. |
2186 | ||
2187 | ??? Addition is not commutative on the PA due to the weird implicit | |
2188 | space register selection rules for memory addresses. Therefore, we | |
2189 | don't consider a + b == b + a. | |
2190 | ||
2191 | We could/should make this test a little tighter. Possibly only | |
2192 | disabling it on the PA via some backend macro or only disabling this | |
2193 | case when the PLUS is inside a MEM. */ | |
5924de0b | 2194 | |
2195 | int | |
2196 | rtx_renumbered_equal_p (x, y) | |
2197 | rtx x, y; | |
2198 | { | |
19cb6b50 | 2199 | int i; |
2200 | RTX_CODE code = GET_CODE (x); | |
2201 | const char *fmt; | |
7113a566 | 2202 | |
5924de0b | 2203 | if (x == y) |
2204 | return 1; | |
6c60c295 | 2205 | |
5924de0b | 2206 | if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)) |
2207 | && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG | |
2208 | && GET_CODE (SUBREG_REG (y)) == REG))) | |
2209 | { | |
6c60c295 | 2210 | int reg_x = -1, reg_y = -1; |
701e46d0 | 2211 | int byte_x = 0, byte_y = 0; |
5924de0b | 2212 | |
2213 | if (GET_MODE (x) != GET_MODE (y)) | |
2214 | return 0; | |
2215 | ||
2216 | /* If we haven't done any renumbering, don't | |
2217 | make any assumptions. */ | |
2218 | if (reg_renumber == 0) | |
2219 | return rtx_equal_p (x, y); | |
2220 | ||
2221 | if (code == SUBREG) | |
2222 | { | |
6c60c295 | 2223 | reg_x = REGNO (SUBREG_REG (x)); |
701e46d0 | 2224 | byte_x = SUBREG_BYTE (x); |
6c60c295 | 2225 | |
2226 | if (reg_renumber[reg_x] >= 0) | |
2227 | { | |
701e46d0 | 2228 | reg_x = subreg_regno_offset (reg_renumber[reg_x], |
2229 | GET_MODE (SUBREG_REG (x)), | |
2230 | byte_x, | |
2231 | GET_MODE (x)); | |
2232 | byte_x = 0; | |
6c60c295 | 2233 | } |
5924de0b | 2234 | } |
2235 | else | |
2236 | { | |
6c60c295 | 2237 | reg_x = REGNO (x); |
2238 | if (reg_renumber[reg_x] >= 0) | |
2239 | reg_x = reg_renumber[reg_x]; | |
5924de0b | 2240 | } |
6c60c295 | 2241 | |
5924de0b | 2242 | if (GET_CODE (y) == SUBREG) |
2243 | { | |
6c60c295 | 2244 | reg_y = REGNO (SUBREG_REG (y)); |
701e46d0 | 2245 | byte_y = SUBREG_BYTE (y); |
6c60c295 | 2246 | |
2247 | if (reg_renumber[reg_y] >= 0) | |
2248 | { | |
701e46d0 | 2249 | reg_y = subreg_regno_offset (reg_renumber[reg_y], |
2250 | GET_MODE (SUBREG_REG (y)), | |
2251 | byte_y, | |
2252 | GET_MODE (y)); | |
2253 | byte_y = 0; | |
6c60c295 | 2254 | } |
5924de0b | 2255 | } |
2256 | else | |
2257 | { | |
6c60c295 | 2258 | reg_y = REGNO (y); |
2259 | if (reg_renumber[reg_y] >= 0) | |
2260 | reg_y = reg_renumber[reg_y]; | |
5924de0b | 2261 | } |
6c60c295 | 2262 | |
701e46d0 | 2263 | return reg_x >= 0 && reg_x == reg_y && byte_x == byte_y; |
5924de0b | 2264 | } |
6c60c295 | 2265 | |
7113a566 | 2266 | /* Now we have disposed of all the cases |
5924de0b | 2267 | in which different rtx codes can match. */ |
2268 | if (code != GET_CODE (y)) | |
2269 | return 0; | |
6c60c295 | 2270 | |
5924de0b | 2271 | switch (code) |
2272 | { | |
2273 | case PC: | |
2274 | case CC0: | |
2275 | case ADDR_VEC: | |
2276 | case ADDR_DIFF_VEC: | |
2277 | return 0; | |
2278 | ||
2279 | case CONST_INT: | |
5fbd420b | 2280 | return INTVAL (x) == INTVAL (y); |
5924de0b | 2281 | |
2282 | case LABEL_REF: | |
f08cae9d | 2283 | /* We can't assume nonlocal labels have their following insns yet. */ |
2284 | if (LABEL_REF_NONLOCAL_P (x) || LABEL_REF_NONLOCAL_P (y)) | |
2285 | return XEXP (x, 0) == XEXP (y, 0); | |
6c60c295 | 2286 | |
5924de0b | 2287 | /* Two label-refs are equivalent if they point at labels |
2288 | in the same position in the instruction stream. */ | |
2289 | return (next_real_insn (XEXP (x, 0)) | |
2290 | == next_real_insn (XEXP (y, 0))); | |
2291 | ||
2292 | case SYMBOL_REF: | |
2293 | return XSTR (x, 0) == XSTR (y, 0); | |
0dbd1c74 | 2294 | |
fc41ccae | 2295 | case CODE_LABEL: |
2296 | /* If we didn't match EQ equality above, they aren't the same. */ | |
2297 | return 0; | |
2298 | ||
0dbd1c74 | 2299 | default: |
2300 | break; | |
5924de0b | 2301 | } |
2302 | ||
2303 | /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ | |
2304 | ||
2305 | if (GET_MODE (x) != GET_MODE (y)) | |
2306 | return 0; | |
2307 | ||
6c60c295 | 2308 | /* For commutative operations, the RTX match if the operand match in any |
2207ad6a | 2309 | order. Also handle the simple binary and unary cases without a loop. |
2310 | ||
2311 | ??? Don't consider PLUS a commutative operator; see comments above. */ | |
2312 | if ((code == EQ || code == NE || GET_RTX_CLASS (code) == 'c') | |
2313 | && code != PLUS) | |
6c60c295 | 2314 | return ((rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) |
2315 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))) | |
2316 | || (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 1)) | |
2317 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 0)))); | |
2318 | else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2') | |
2319 | return (rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)) | |
2320 | && rtx_renumbered_equal_p (XEXP (x, 1), XEXP (y, 1))); | |
2321 | else if (GET_RTX_CLASS (code) == '1') | |
2322 | return rtx_renumbered_equal_p (XEXP (x, 0), XEXP (y, 0)); | |
2323 | ||
5924de0b | 2324 | /* Compare the elements. If any pair of corresponding elements |
2325 | fail to match, return 0 for the whole things. */ | |
2326 | ||
2327 | fmt = GET_RTX_FORMAT (code); | |
2328 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
2329 | { | |
19cb6b50 | 2330 | int j; |
5924de0b | 2331 | switch (fmt[i]) |
2332 | { | |
1bb04728 | 2333 | case 'w': |
2334 | if (XWINT (x, i) != XWINT (y, i)) | |
2335 | return 0; | |
2336 | break; | |
2337 | ||
5924de0b | 2338 | case 'i': |
2339 | if (XINT (x, i) != XINT (y, i)) | |
2340 | return 0; | |
2341 | break; | |
2342 | ||
a0d79d69 | 2343 | case 't': |
2344 | if (XTREE (x, i) != XTREE (y, i)) | |
2345 | return 0; | |
2346 | break; | |
2347 | ||
5924de0b | 2348 | case 's': |
2349 | if (strcmp (XSTR (x, i), XSTR (y, i))) | |
2350 | return 0; | |
2351 | break; | |
2352 | ||
2353 | case 'e': | |
2354 | if (! rtx_renumbered_equal_p (XEXP (x, i), XEXP (y, i))) | |
2355 | return 0; | |
2356 | break; | |
2357 | ||
2358 | case 'u': | |
2359 | if (XEXP (x, i) != XEXP (y, i)) | |
2360 | return 0; | |
2361 | /* fall through. */ | |
2362 | case '0': | |
2363 | break; | |
2364 | ||
2365 | case 'E': | |
2366 | if (XVECLEN (x, i) != XVECLEN (y, i)) | |
2367 | return 0; | |
2368 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) | |
2369 | if (!rtx_renumbered_equal_p (XVECEXP (x, i, j), XVECEXP (y, i, j))) | |
2370 | return 0; | |
2371 | break; | |
2372 | ||
2373 | default: | |
2374 | abort (); | |
2375 | } | |
2376 | } | |
2377 | return 1; | |
2378 | } | |
2379 | \f | |
2380 | /* If X is a hard register or equivalent to one or a subregister of one, | |
2381 | return the hard register number. If X is a pseudo register that was not | |
2382 | assigned a hard register, return the pseudo register number. Otherwise, | |
2383 | return -1. Any rtx is valid for X. */ | |
2384 | ||
2385 | int | |
2386 | true_regnum (x) | |
2387 | rtx x; | |
2388 | { | |
2389 | if (GET_CODE (x) == REG) | |
2390 | { | |
2391 | if (REGNO (x) >= FIRST_PSEUDO_REGISTER && reg_renumber[REGNO (x)] >= 0) | |
2392 | return reg_renumber[REGNO (x)]; | |
2393 | return REGNO (x); | |
2394 | } | |
2395 | if (GET_CODE (x) == SUBREG) | |
2396 | { | |
2397 | int base = true_regnum (SUBREG_REG (x)); | |
2398 | if (base >= 0 && base < FIRST_PSEUDO_REGISTER) | |
701e46d0 | 2399 | return base + subreg_regno_offset (REGNO (SUBREG_REG (x)), |
2400 | GET_MODE (SUBREG_REG (x)), | |
2401 | SUBREG_BYTE (x), GET_MODE (x)); | |
5924de0b | 2402 | } |
2403 | return -1; | |
2404 | } | |
b627bae7 | 2405 | |
2406 | /* Return regno of the register REG and handle subregs too. */ | |
2407 | unsigned int | |
2408 | reg_or_subregno (reg) | |
2409 | rtx reg; | |
2410 | { | |
2411 | if (REG_P (reg)) | |
2412 | return REGNO (reg); | |
2413 | if (GET_CODE (reg) == SUBREG) | |
2414 | return REGNO (SUBREG_REG (reg)); | |
2415 | abort (); | |
2416 | } |