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Commit | Line | Data |
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ca6c03ca JH |
1 | /* Control flow graph manipulation code for GNU compiler. |
2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, | |
d9221e01 | 3 | 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc. |
ca6c03ca JH |
4 | |
5 | This file is part of GCC. | |
6 | ||
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. | |
11 | ||
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. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
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. */ | |
21 | ||
5f0d2358 RK |
22 | /* This file contains low level functions to manipulate the CFG and analyze it |
23 | that are aware of the RTL intermediate language. | |
ca6c03ca JH |
24 | |
25 | Available functionality: | |
bc35512f | 26 | - Basic CFG/RTL manipulation API documented in cfghooks.h |
5f0d2358 | 27 | - CFG-aware instruction chain manipulation |
ca6c03ca | 28 | delete_insn, delete_insn_chain |
bc35512f JH |
29 | - Edge splitting and committing to edges |
30 | insert_insn_on_edge, commit_edge_insertions | |
31 | - CFG updating after insn simplification | |
32 | purge_dead_edges, purge_all_dead_edges | |
33 | ||
34 | Functions not supposed for generic use: | |
5f0d2358 | 35 | - Infrastructure to determine quickly basic block for insn |
ca6c03ca | 36 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5f0d2358 | 37 | - Edge redirection with updating and optimizing of insn chain |
bc35512f | 38 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
ca6c03ca JH |
39 | \f |
40 | #include "config.h" | |
41 | #include "system.h" | |
4977bab6 ZW |
42 | #include "coretypes.h" |
43 | #include "tm.h" | |
ca6c03ca JH |
44 | #include "tree.h" |
45 | #include "rtl.h" | |
46 | #include "hard-reg-set.h" | |
47 | #include "basic-block.h" | |
48 | #include "regs.h" | |
49 | #include "flags.h" | |
50 | #include "output.h" | |
51 | #include "function.h" | |
52 | #include "except.h" | |
53 | #include "toplev.h" | |
54 | #include "tm_p.h" | |
55 | #include "obstack.h" | |
0a2ed1f1 | 56 | #include "insn-config.h" |
9ee634e3 | 57 | #include "cfglayout.h" |
ff25ef99 | 58 | #include "expr.h" |
ca6c03ca | 59 | |
ca6c03ca | 60 | |
ca6c03ca JH |
61 | /* The labels mentioned in non-jump rtl. Valid during find_basic_blocks. */ |
62 | /* ??? Should probably be using LABEL_NUSES instead. It would take a | |
63 | bit of surgery to be able to use or co-opt the routines in jump. */ | |
ca6c03ca JH |
64 | rtx label_value_list; |
65 | rtx tail_recursion_label_list; | |
66 | ||
d329e058 AJ |
67 | static int can_delete_note_p (rtx); |
68 | static int can_delete_label_p (rtx); | |
69 | static void commit_one_edge_insertion (edge, int); | |
d329e058 AJ |
70 | static rtx last_loop_beg_note (rtx); |
71 | static bool back_edge_of_syntactic_loop_p (basic_block, basic_block); | |
72 | basic_block force_nonfallthru_and_redirect (edge, basic_block); | |
73 | static basic_block rtl_split_edge (edge); | |
f470c378 | 74 | static bool rtl_move_block_after (basic_block, basic_block); |
d329e058 | 75 | static int rtl_verify_flow_info (void); |
f470c378 | 76 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 77 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
78 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
79 | static void cfg_layout_delete_block (basic_block); | |
80 | static void rtl_delete_block (basic_block); | |
81 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
6de9cd9a | 82 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 ZD |
83 | static basic_block rtl_split_block (basic_block, void *); |
84 | static void rtl_dump_bb (basic_block, FILE *, int); | |
d329e058 | 85 | static int rtl_verify_flow_info_1 (void); |
ff25ef99 | 86 | static void mark_killed_regs (rtx, rtx, void *); |
f470c378 | 87 | static void rtl_make_forwarder_block (edge); |
ca6c03ca JH |
88 | \f |
89 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 90 | so that we may simply delete it. */ |
ca6c03ca JH |
91 | |
92 | static int | |
d329e058 | 93 | can_delete_note_p (rtx note) |
ca6c03ca JH |
94 | { |
95 | return (NOTE_LINE_NUMBER (note) == NOTE_INSN_DELETED | |
969d70ca | 96 | || NOTE_LINE_NUMBER (note) == NOTE_INSN_BASIC_BLOCK |
750054a2 | 97 | || NOTE_LINE_NUMBER (note) == NOTE_INSN_UNLIKELY_EXECUTED_CODE |
f87c27b4 | 98 | || NOTE_LINE_NUMBER (note) == NOTE_INSN_PREDICTION); |
ca6c03ca JH |
99 | } |
100 | ||
101 | /* True if a given label can be deleted. */ | |
102 | ||
103 | static int | |
d329e058 | 104 | can_delete_label_p (rtx label) |
ca6c03ca | 105 | { |
5f0d2358 RK |
106 | return (!LABEL_PRESERVE_P (label) |
107 | /* User declared labels must be preserved. */ | |
108 | && LABEL_NAME (label) == 0 | |
109 | && !in_expr_list_p (forced_labels, label) | |
6a58eee9 | 110 | && !in_expr_list_p (label_value_list, label)); |
ca6c03ca JH |
111 | } |
112 | ||
113 | /* Delete INSN by patching it out. Return the next insn. */ | |
114 | ||
115 | rtx | |
d329e058 | 116 | delete_insn (rtx insn) |
ca6c03ca JH |
117 | { |
118 | rtx next = NEXT_INSN (insn); | |
119 | rtx note; | |
120 | bool really_delete = true; | |
121 | ||
122 | if (GET_CODE (insn) == CODE_LABEL) | |
123 | { | |
124 | /* Some labels can't be directly removed from the INSN chain, as they | |
f87c27b4 | 125 | might be references via variables, constant pool etc. |
ca6c03ca JH |
126 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ |
127 | if (! can_delete_label_p (insn)) | |
128 | { | |
129 | const char *name = LABEL_NAME (insn); | |
130 | ||
131 | really_delete = false; | |
132 | PUT_CODE (insn, NOTE); | |
133 | NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED_LABEL; | |
134 | NOTE_SOURCE_FILE (insn) = name; | |
135 | } | |
5f0d2358 | 136 | |
ca6c03ca JH |
137 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
138 | } | |
139 | ||
140 | if (really_delete) | |
141 | { | |
cda94cbb RH |
142 | /* If this insn has already been deleted, something is very wrong. */ |
143 | if (INSN_DELETED_P (insn)) | |
144 | abort (); | |
ca6c03ca JH |
145 | remove_insn (insn); |
146 | INSN_DELETED_P (insn) = 1; | |
147 | } | |
148 | ||
149 | /* If deleting a jump, decrement the use count of the label. Deleting | |
150 | the label itself should happen in the normal course of block merging. */ | |
151 | if (GET_CODE (insn) == JUMP_INSN | |
152 | && JUMP_LABEL (insn) | |
153 | && GET_CODE (JUMP_LABEL (insn)) == CODE_LABEL) | |
154 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
155 | ||
156 | /* Also if deleting an insn that references a label. */ | |
9295a326 JZ |
157 | else |
158 | { | |
159 | while ((note = find_reg_note (insn, REG_LABEL, NULL_RTX)) != NULL_RTX | |
160 | && GET_CODE (XEXP (note, 0)) == CODE_LABEL) | |
161 | { | |
162 | LABEL_NUSES (XEXP (note, 0))--; | |
163 | remove_note (insn, note); | |
164 | } | |
165 | } | |
ca6c03ca JH |
166 | |
167 | if (GET_CODE (insn) == JUMP_INSN | |
168 | && (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
169 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)) | |
170 | { | |
171 | rtx pat = PATTERN (insn); | |
172 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
173 | int len = XVECLEN (pat, diff_vec_p); | |
174 | int i; | |
175 | ||
176 | for (i = 0; i < len; i++) | |
a124fcda RH |
177 | { |
178 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
179 | ||
180 | /* When deleting code in bulk (e.g. removing many unreachable | |
181 | blocks) we can delete a label that's a target of the vector | |
182 | before deleting the vector itself. */ | |
183 | if (GET_CODE (label) != NOTE) | |
184 | LABEL_NUSES (label)--; | |
185 | } | |
ca6c03ca JH |
186 | } |
187 | ||
188 | return next; | |
189 | } | |
190 | ||
3dec4024 JH |
191 | /* Like delete_insn but also purge dead edges from BB. */ |
192 | rtx | |
d329e058 | 193 | delete_insn_and_edges (rtx insn) |
3dec4024 JH |
194 | { |
195 | rtx x; | |
196 | bool purge = false; | |
197 | ||
ba4f7968 | 198 | if (INSN_P (insn) |
3dec4024 | 199 | && BLOCK_FOR_INSN (insn) |
a813c111 | 200 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 JH |
201 | purge = true; |
202 | x = delete_insn (insn); | |
203 | if (purge) | |
204 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
205 | return x; | |
206 | } | |
207 | ||
ca6c03ca JH |
208 | /* Unlink a chain of insns between START and FINISH, leaving notes |
209 | that must be paired. */ | |
210 | ||
211 | void | |
d329e058 | 212 | delete_insn_chain (rtx start, rtx finish) |
ca6c03ca | 213 | { |
ca6c03ca JH |
214 | rtx next; |
215 | ||
5f0d2358 RK |
216 | /* Unchain the insns one by one. It would be quicker to delete all of these |
217 | with a single unchaining, rather than one at a time, but we need to keep | |
218 | the NOTE's. */ | |
ca6c03ca JH |
219 | while (1) |
220 | { | |
221 | next = NEXT_INSN (start); | |
222 | if (GET_CODE (start) == NOTE && !can_delete_note_p (start)) | |
223 | ; | |
224 | else | |
225 | next = delete_insn (start); | |
226 | ||
227 | if (start == finish) | |
228 | break; | |
229 | start = next; | |
230 | } | |
231 | } | |
3dec4024 JH |
232 | |
233 | /* Like delete_insn but also purge dead edges from BB. */ | |
234 | void | |
d329e058 | 235 | delete_insn_chain_and_edges (rtx first, rtx last) |
3dec4024 JH |
236 | { |
237 | bool purge = false; | |
238 | ||
ba4f7968 | 239 | if (INSN_P (last) |
3dec4024 | 240 | && BLOCK_FOR_INSN (last) |
a813c111 | 241 | && BB_END (BLOCK_FOR_INSN (last)) == last) |
3dec4024 JH |
242 | purge = true; |
243 | delete_insn_chain (first, last); | |
244 | if (purge) | |
245 | purge_dead_edges (BLOCK_FOR_INSN (last)); | |
246 | } | |
ca6c03ca | 247 | \f |
5f0d2358 RK |
248 | /* Create a new basic block consisting of the instructions between HEAD and END |
249 | inclusive. This function is designed to allow fast BB construction - reuses | |
250 | the note and basic block struct in BB_NOTE, if any and do not grow | |
251 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
252 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
253 | and HEAD can be NULL to create basic block at the end of INSN chain. |
254 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
255 | |
256 | basic_block | |
d329e058 | 257 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
258 | { |
259 | basic_block bb; | |
260 | ||
261 | if (bb_note | |
ca6c03ca JH |
262 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
263 | && bb->aux == NULL) | |
264 | { | |
265 | /* If we found an existing note, thread it back onto the chain. */ | |
266 | ||
267 | rtx after; | |
268 | ||
269 | if (GET_CODE (head) == CODE_LABEL) | |
270 | after = head; | |
271 | else | |
272 | { | |
273 | after = PREV_INSN (head); | |
274 | head = bb_note; | |
275 | } | |
276 | ||
277 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 278 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
279 | } |
280 | else | |
281 | { | |
282 | /* Otherwise we must create a note and a basic block structure. */ | |
283 | ||
284 | bb = alloc_block (); | |
285 | ||
286 | if (!head && !end) | |
5f0d2358 RK |
287 | head = end = bb_note |
288 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
ca6c03ca JH |
289 | else if (GET_CODE (head) == CODE_LABEL && end) |
290 | { | |
291 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
292 | if (head == end) | |
293 | end = bb_note; | |
294 | } | |
295 | else | |
296 | { | |
297 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
298 | head = bb_note; | |
299 | if (!end) | |
300 | end = head; | |
301 | } | |
5f0d2358 | 302 | |
ca6c03ca JH |
303 | NOTE_BASIC_BLOCK (bb_note) = bb; |
304 | } | |
305 | ||
306 | /* Always include the bb note in the block. */ | |
307 | if (NEXT_INSN (end) == bb_note) | |
308 | end = bb_note; | |
309 | ||
a813c111 SB |
310 | BB_HEAD (bb) = head; |
311 | BB_END (bb) = end; | |
852c6ec7 | 312 | bb->index = last_basic_block++; |
38c1593d | 313 | bb->flags = BB_NEW; |
918ed612 | 314 | link_block (bb, after); |
852c6ec7 | 315 | BASIC_BLOCK (bb->index) = bb; |
ba4f7968 | 316 | update_bb_for_insn (bb); |
750054a2 | 317 | bb->partition = UNPARTITIONED; |
ca6c03ca JH |
318 | |
319 | /* Tag the block so that we know it has been used when considering | |
320 | other basic block notes. */ | |
321 | bb->aux = bb; | |
322 | ||
323 | return bb; | |
324 | } | |
325 | ||
5f0d2358 | 326 | /* Create new basic block consisting of instructions in between HEAD and END |
918ed612 | 327 | and place it to the BB chain after block AFTER. END can be NULL in to |
5f0d2358 RK |
328 | create new empty basic block before HEAD. Both END and HEAD can be NULL to |
329 | create basic block at the end of INSN chain. */ | |
ca6c03ca | 330 | |
bc35512f JH |
331 | static basic_block |
332 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 333 | { |
bc35512f | 334 | rtx head = headp, end = endp; |
ca6c03ca | 335 | basic_block bb; |
0b17ab2f | 336 | |
7eca0767 JH |
337 | /* Grow the basic block array if needed. */ |
338 | if ((size_t) last_basic_block >= VARRAY_SIZE (basic_block_info)) | |
339 | { | |
340 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; | |
341 | VARRAY_GROW (basic_block_info, new_size); | |
342 | } | |
0b17ab2f | 343 | |
bf77398c | 344 | n_basic_blocks++; |
ca6c03ca | 345 | |
852c6ec7 | 346 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
347 | bb->aux = NULL; |
348 | return bb; | |
349 | } | |
bc35512f JH |
350 | |
351 | static basic_block | |
352 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
353 | { | |
354 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
355 | ||
6de9cd9a | 356 | initialize_bb_rbi (newbb); |
bc35512f JH |
357 | return newbb; |
358 | } | |
ca6c03ca JH |
359 | \f |
360 | /* Delete the insns in a (non-live) block. We physically delete every | |
361 | non-deleted-note insn, and update the flow graph appropriately. | |
362 | ||
363 | Return nonzero if we deleted an exception handler. */ | |
364 | ||
365 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
366 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
367 | ||
f0fda11c | 368 | static void |
d329e058 | 369 | rtl_delete_block (basic_block b) |
ca6c03ca | 370 | { |
ca6c03ca JH |
371 | rtx insn, end, tmp; |
372 | ||
373 | /* If the head of this block is a CODE_LABEL, then it might be the | |
374 | label for an exception handler which can't be reached. | |
375 | ||
376 | We need to remove the label from the exception_handler_label list | |
377 | and remove the associated NOTE_INSN_EH_REGION_BEG and | |
378 | NOTE_INSN_EH_REGION_END notes. */ | |
379 | ||
07532fad RS |
380 | /* Get rid of all NOTE_INSN_PREDICTIONs and NOTE_INSN_LOOP_CONTs |
381 | hanging before the block. */ | |
f87c27b4 | 382 | |
a813c111 | 383 | for (insn = PREV_INSN (BB_HEAD (b)); insn; insn = PREV_INSN (insn)) |
969d70ca JH |
384 | { |
385 | if (GET_CODE (insn) != NOTE) | |
f87c27b4 | 386 | break; |
07532fad RS |
387 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PREDICTION |
388 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_CONT) | |
f87c27b4 | 389 | NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED; |
969d70ca JH |
390 | } |
391 | ||
a813c111 | 392 | insn = BB_HEAD (b); |
ca6c03ca | 393 | |
ca6c03ca JH |
394 | if (GET_CODE (insn) == CODE_LABEL) |
395 | maybe_remove_eh_handler (insn); | |
396 | ||
397 | /* Include any jump table following the basic block. */ | |
a813c111 | 398 | end = BB_END (b); |
e1233a7d | 399 | if (tablejump_p (end, NULL, &tmp)) |
ca6c03ca JH |
400 | end = tmp; |
401 | ||
402 | /* Include any barrier that may follow the basic block. */ | |
403 | tmp = next_nonnote_insn (end); | |
404 | if (tmp && GET_CODE (tmp) == BARRIER) | |
405 | end = tmp; | |
406 | ||
407 | /* Selectively delete the entire chain. */ | |
a813c111 | 408 | BB_HEAD (b) = NULL; |
ca6c03ca | 409 | delete_insn_chain (insn, end); |
ca6c03ca JH |
410 | } |
411 | \f | |
852c6ec7 | 412 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
413 | |
414 | void | |
d329e058 | 415 | compute_bb_for_insn (void) |
ca6c03ca | 416 | { |
e0082a72 | 417 | basic_block bb; |
ca6c03ca | 418 | |
e0082a72 | 419 | FOR_EACH_BB (bb) |
ca6c03ca | 420 | { |
a813c111 | 421 | rtx end = BB_END (bb); |
5f0d2358 | 422 | rtx insn; |
ca6c03ca | 423 | |
a813c111 | 424 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 425 | { |
ba4f7968 | 426 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
427 | if (insn == end) |
428 | break; | |
ca6c03ca JH |
429 | } |
430 | } | |
431 | } | |
432 | ||
433 | /* Release the basic_block_for_insn array. */ | |
434 | ||
435 | void | |
d329e058 | 436 | free_bb_for_insn (void) |
ca6c03ca | 437 | { |
ba4f7968 JH |
438 | rtx insn; |
439 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
440 | if (GET_CODE (insn) != BARRIER) | |
441 | BLOCK_FOR_INSN (insn) = NULL; | |
ca6c03ca JH |
442 | } |
443 | ||
444 | /* Update insns block within BB. */ | |
445 | ||
446 | void | |
d329e058 | 447 | update_bb_for_insn (basic_block bb) |
ca6c03ca JH |
448 | { |
449 | rtx insn; | |
450 | ||
a813c111 | 451 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 452 | { |
bcc53e2a JH |
453 | if (GET_CODE (insn) != BARRIER) |
454 | set_block_for_insn (insn, bb); | |
a813c111 | 455 | if (insn == BB_END (bb)) |
ca6c03ca JH |
456 | break; |
457 | } | |
458 | } | |
ca6c03ca | 459 | \f |
f470c378 ZD |
460 | /* Creates a new basic block just after basic block B by splitting |
461 | everything after specified instruction I. */ | |
ca6c03ca | 462 | |
f470c378 | 463 | static basic_block |
d329e058 | 464 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
465 | { |
466 | basic_block new_bb; | |
9ee634e3 | 467 | rtx insn = insnp; |
f470c378 | 468 | edge e; |
ca6c03ca | 469 | |
f470c378 ZD |
470 | if (!insn) |
471 | { | |
472 | insn = first_insn_after_basic_block_note (bb); | |
473 | ||
474 | if (insn) | |
475 | insn = PREV_INSN (insn); | |
476 | else | |
477 | insn = get_last_insn (); | |
478 | } | |
479 | ||
480 | /* We probably should check type of the insn so that we do not create | |
481 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
482 | bother. */ | |
483 | if (insn == BB_END (bb)) | |
484 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
485 | |
486 | /* Create the new basic block. */ | |
a813c111 | 487 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
a813c111 | 488 | BB_END (bb) = insn; |
ca6c03ca JH |
489 | |
490 | /* Redirect the outgoing edges. */ | |
491 | new_bb->succ = bb->succ; | |
492 | bb->succ = NULL; | |
493 | for (e = new_bb->succ; e; e = e->succ_next) | |
494 | e->src = new_bb; | |
495 | ||
ca6c03ca JH |
496 | if (bb->global_live_at_start) |
497 | { | |
498 | new_bb->global_live_at_start = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
499 | new_bb->global_live_at_end = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
500 | COPY_REG_SET (new_bb->global_live_at_end, bb->global_live_at_end); | |
501 | ||
502 | /* We now have to calculate which registers are live at the end | |
503 | of the split basic block and at the start of the new basic | |
504 | block. Start with those registers that are known to be live | |
505 | at the end of the original basic block and get | |
506 | propagate_block to determine which registers are live. */ | |
507 | COPY_REG_SET (new_bb->global_live_at_start, bb->global_live_at_end); | |
508 | propagate_block (new_bb, new_bb->global_live_at_start, NULL, NULL, 0); | |
509 | COPY_REG_SET (bb->global_live_at_end, | |
510 | new_bb->global_live_at_start); | |
0a2ed1f1 JH |
511 | #ifdef HAVE_conditional_execution |
512 | /* In the presence of conditional execution we are not able to update | |
513 | liveness precisely. */ | |
514 | if (reload_completed) | |
515 | { | |
516 | bb->flags |= BB_DIRTY; | |
517 | new_bb->flags |= BB_DIRTY; | |
518 | } | |
519 | #endif | |
ca6c03ca JH |
520 | } |
521 | ||
f470c378 | 522 | return new_bb; |
bc35512f JH |
523 | } |
524 | ||
ca6c03ca | 525 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 526 | are already contiguous. */ |
ca6c03ca | 527 | |
bc35512f JH |
528 | static void |
529 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 530 | { |
a813c111 | 531 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca JH |
532 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
533 | int b_empty = 0; | |
534 | ||
535 | /* If there was a CODE_LABEL beginning B, delete it. */ | |
ca6c03ca JH |
536 | if (GET_CODE (b_head) == CODE_LABEL) |
537 | { | |
538 | /* Detect basic blocks with nothing but a label. This can happen | |
539 | in particular at the end of a function. */ | |
540 | if (b_head == b_end) | |
541 | b_empty = 1; | |
5f0d2358 | 542 | |
ca6c03ca JH |
543 | del_first = del_last = b_head; |
544 | b_head = NEXT_INSN (b_head); | |
545 | } | |
546 | ||
5f0d2358 RK |
547 | /* Delete the basic block note and handle blocks containing just that |
548 | note. */ | |
ca6c03ca JH |
549 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
550 | { | |
551 | if (b_head == b_end) | |
552 | b_empty = 1; | |
553 | if (! del_last) | |
554 | del_first = b_head; | |
5f0d2358 | 555 | |
ca6c03ca JH |
556 | del_last = b_head; |
557 | b_head = NEXT_INSN (b_head); | |
558 | } | |
559 | ||
560 | /* If there was a jump out of A, delete it. */ | |
ca6c03ca JH |
561 | if (GET_CODE (a_end) == JUMP_INSN) |
562 | { | |
563 | rtx prev; | |
564 | ||
565 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
566 | if (GET_CODE (prev) != NOTE | |
567 | || NOTE_LINE_NUMBER (prev) == NOTE_INSN_BASIC_BLOCK | |
a813c111 | 568 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
569 | break; |
570 | ||
571 | del_first = a_end; | |
572 | ||
573 | #ifdef HAVE_cc0 | |
574 | /* If this was a conditional jump, we need to also delete | |
575 | the insn that set cc0. */ | |
576 | if (only_sets_cc0_p (prev)) | |
577 | { | |
578 | rtx tmp = prev; | |
5f0d2358 | 579 | |
ca6c03ca JH |
580 | prev = prev_nonnote_insn (prev); |
581 | if (!prev) | |
a813c111 | 582 | prev = BB_HEAD (a); |
ca6c03ca JH |
583 | del_first = tmp; |
584 | } | |
585 | #endif | |
586 | ||
587 | a_end = PREV_INSN (del_first); | |
588 | } | |
589 | else if (GET_CODE (NEXT_INSN (a_end)) == BARRIER) | |
590 | del_first = NEXT_INSN (a_end); | |
591 | ||
ca6c03ca JH |
592 | /* Delete everything marked above as well as crap that might be |
593 | hanging out between the two blocks. */ | |
f470c378 | 594 | BB_HEAD (b) = NULL; |
ca6c03ca JH |
595 | delete_insn_chain (del_first, del_last); |
596 | ||
597 | /* Reassociate the insns of B with A. */ | |
598 | if (!b_empty) | |
599 | { | |
ba4f7968 | 600 | rtx x; |
5f0d2358 | 601 | |
ba4f7968 JH |
602 | for (x = a_end; x != b_end; x = NEXT_INSN (x)) |
603 | set_block_for_insn (x, a); | |
5f0d2358 | 604 | |
ba4f7968 | 605 | set_block_for_insn (b_end, a); |
5f0d2358 | 606 | |
ca6c03ca JH |
607 | a_end = b_end; |
608 | } | |
5f0d2358 | 609 | |
a813c111 | 610 | BB_END (a) = a_end; |
ca6c03ca | 611 | } |
bc35512f JH |
612 | |
613 | /* Return true when block A and B can be merged. */ | |
614 | static bool | |
615 | rtl_can_merge_blocks (basic_block a,basic_block b) | |
616 | { | |
750054a2 CT |
617 | bool partitions_ok = true; |
618 | ||
619 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
620 | mess up unconditional or indirect jumps that cross between hot | |
621 | and cold sections. */ | |
622 | ||
623 | if (flag_reorder_blocks_and_partition | |
624 | && (find_reg_note (BB_END (a), REG_CROSSING_JUMP, NULL_RTX) | |
625 | || find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX) | |
626 | || a->partition != b->partition)) | |
627 | partitions_ok = false; | |
628 | ||
bc35512f JH |
629 | /* There must be exactly one edge in between the blocks. */ |
630 | return (a->succ && !a->succ->succ_next && a->succ->dest == b | |
631 | && !b->pred->pred_next && a != b | |
632 | /* Must be simple edge. */ | |
633 | && !(a->succ->flags & EDGE_COMPLEX) | |
750054a2 | 634 | && partitions_ok |
bc35512f JH |
635 | && a->next_bb == b |
636 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR | |
637 | /* If the jump insn has side effects, | |
638 | we can't kill the edge. */ | |
a813c111 | 639 | && (GET_CODE (BB_END (a)) != JUMP_INSN |
e24e7211 | 640 | || (reload_completed |
a813c111 | 641 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 642 | } |
ca6c03ca | 643 | \f |
5f0d2358 RK |
644 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
645 | exist. */ | |
ca6c03ca JH |
646 | |
647 | rtx | |
d329e058 | 648 | block_label (basic_block block) |
ca6c03ca JH |
649 | { |
650 | if (block == EXIT_BLOCK_PTR) | |
651 | return NULL_RTX; | |
5f0d2358 | 652 | |
a813c111 | 653 | if (GET_CODE (BB_HEAD (block)) != CODE_LABEL) |
ca6c03ca | 654 | { |
a813c111 | 655 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 656 | } |
5f0d2358 | 657 | |
a813c111 | 658 | return BB_HEAD (block); |
ca6c03ca JH |
659 | } |
660 | ||
661 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
662 | instruction by unconditional jump or removing jump completely. This can |
663 | apply only if all edges now point to the same block. The parameters and | |
664 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 665 | |
6de9cd9a | 666 | edge |
bc35512f | 667 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
668 | { |
669 | basic_block src = e->src; | |
a813c111 | 670 | rtx insn = BB_END (src), kill_from; |
ca6c03ca | 671 | edge tmp; |
e1233a7d | 672 | rtx set; |
ca6c03ca JH |
673 | int fallthru = 0; |
674 | ||
750054a2 CT |
675 | |
676 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
677 | mess up unconditional or indirect jumps that cross between hot | |
678 | and cold sections. */ | |
679 | ||
680 | if (flag_reorder_blocks_and_partition | |
681 | && find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)) | |
682 | return false; | |
683 | ||
ca6c03ca JH |
684 | /* Verify that all targets will be TARGET. */ |
685 | for (tmp = src->succ; tmp; tmp = tmp->succ_next) | |
686 | if (tmp->dest != target && tmp != e) | |
687 | break; | |
5f0d2358 | 688 | |
ca6c03ca | 689 | if (tmp || !onlyjump_p (insn)) |
6de9cd9a | 690 | return NULL; |
3348b696 | 691 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 692 | return NULL; |
ca6c03ca JH |
693 | |
694 | /* Avoid removing branch with side effects. */ | |
695 | set = single_set (insn); | |
696 | if (!set || side_effects_p (set)) | |
6de9cd9a | 697 | return NULL; |
ca6c03ca JH |
698 | |
699 | /* In case we zap a conditional jump, we'll need to kill | |
700 | the cc0 setter too. */ | |
701 | kill_from = insn; | |
702 | #ifdef HAVE_cc0 | |
703 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn))) | |
704 | kill_from = PREV_INSN (insn); | |
705 | #endif | |
706 | ||
707 | /* See if we can create the fallthru edge. */ | |
bc35512f | 708 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 709 | { |
c263766c RH |
710 | if (dump_file) |
711 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
712 | fallthru = 1; |
713 | ||
eaec9b3d | 714 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
715 | if (in_cfglayout) |
716 | { | |
717 | rtx insn = src->rbi->footer; | |
718 | ||
a813c111 | 719 | delete_insn_chain (kill_from, BB_END (src)); |
bc35512f JH |
720 | |
721 | /* Remove barriers but keep jumptables. */ | |
722 | while (insn) | |
723 | { | |
724 | if (GET_CODE (insn) == BARRIER) | |
725 | { | |
726 | if (PREV_INSN (insn)) | |
727 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
728 | else | |
729 | src->rbi->footer = NEXT_INSN (insn); | |
730 | if (NEXT_INSN (insn)) | |
731 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
732 | } | |
733 | if (GET_CODE (insn) == CODE_LABEL) | |
734 | break; | |
735 | insn = NEXT_INSN (insn); | |
736 | } | |
737 | } | |
738 | else | |
a813c111 | 739 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target))); |
ca6c03ca | 740 | } |
5f0d2358 | 741 | |
ca6c03ca JH |
742 | /* If this already is simplejump, redirect it. */ |
743 | else if (simplejump_p (insn)) | |
744 | { | |
745 | if (e->dest == target) | |
6de9cd9a | 746 | return NULL; |
c263766c RH |
747 | if (dump_file) |
748 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 749 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
750 | if (!redirect_jump (insn, block_label (target), 0)) |
751 | { | |
752 | if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 753 | return NULL; |
6ee3c8e4 JJ |
754 | abort (); |
755 | } | |
ca6c03ca | 756 | } |
5f0d2358 | 757 | |
6ee3c8e4 JJ |
758 | /* Cannot do anything for target exit block. */ |
759 | else if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 760 | return NULL; |
6ee3c8e4 | 761 | |
ca6c03ca JH |
762 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
763 | else | |
764 | { | |
765 | rtx target_label = block_label (target); | |
eb5b8ad4 | 766 | rtx barrier, label, table; |
ca6c03ca | 767 | |
09eb1aab | 768 | emit_jump_insn_after (gen_jump (target_label), insn); |
a813c111 | 769 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 770 | LABEL_NUSES (target_label)++; |
c263766c RH |
771 | if (dump_file) |
772 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 773 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 774 | |
4da2eb6b | 775 | |
ca6c03ca JH |
776 | delete_insn_chain (kill_from, insn); |
777 | ||
4da2eb6b RH |
778 | /* Recognize a tablejump that we are converting to a |
779 | simple jump and remove its associated CODE_LABEL | |
780 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
3348b696 | 781 | if (tablejump_p (insn, &label, &table)) |
4da2eb6b | 782 | delete_insn_chain (label, table); |
eb5b8ad4 | 783 | |
a813c111 | 784 | barrier = next_nonnote_insn (BB_END (src)); |
ca6c03ca | 785 | if (!barrier || GET_CODE (barrier) != BARRIER) |
a813c111 | 786 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
787 | else |
788 | { | |
a813c111 | 789 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
790 | { |
791 | /* Move the jump before barrier so that the notes | |
792 | which originally were or were created before jump table are | |
793 | inside the basic block. */ | |
a813c111 | 794 | rtx new_insn = BB_END (src); |
5d693491 JZ |
795 | rtx tmp; |
796 | ||
a813c111 | 797 | for (tmp = NEXT_INSN (BB_END (src)); tmp != barrier; |
5d693491 JZ |
798 | tmp = NEXT_INSN (tmp)) |
799 | set_block_for_insn (tmp, src); | |
800 | ||
801 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
802 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
803 | ||
804 | NEXT_INSN (new_insn) = barrier; | |
805 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
806 | ||
807 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
808 | PREV_INSN (barrier) = new_insn; | |
809 | } | |
810 | } | |
ca6c03ca JH |
811 | } |
812 | ||
813 | /* Keep only one edge out and set proper flags. */ | |
814 | while (src->succ->succ_next) | |
815 | remove_edge (src->succ); | |
816 | e = src->succ; | |
817 | if (fallthru) | |
818 | e->flags = EDGE_FALLTHRU; | |
819 | else | |
820 | e->flags = 0; | |
5f0d2358 | 821 | |
ca6c03ca JH |
822 | e->probability = REG_BR_PROB_BASE; |
823 | e->count = src->count; | |
824 | ||
825 | /* We don't want a block to end on a line-number note since that has | |
826 | the potential of changing the code between -g and not -g. */ | |
a813c111 SB |
827 | while (GET_CODE (BB_END (e->src)) == NOTE |
828 | && NOTE_LINE_NUMBER (BB_END (e->src)) >= 0) | |
829 | delete_insn (BB_END (e->src)); | |
ca6c03ca JH |
830 | |
831 | if (e->dest != target) | |
832 | redirect_edge_succ (e, target); | |
5f0d2358 | 833 | |
6de9cd9a | 834 | return e; |
ca6c03ca JH |
835 | } |
836 | ||
837 | /* Return last loop_beg note appearing after INSN, before start of next | |
838 | basic block. Return INSN if there are no such notes. | |
839 | ||
09da1532 | 840 | When emitting jump to redirect a fallthru edge, it should always appear |
5f0d2358 RK |
841 | after the LOOP_BEG notes, as loop optimizer expect loop to either start by |
842 | fallthru edge or jump following the LOOP_BEG note jumping to the loop exit | |
843 | test. */ | |
ca6c03ca JH |
844 | |
845 | static rtx | |
d329e058 | 846 | last_loop_beg_note (rtx insn) |
ca6c03ca JH |
847 | { |
848 | rtx last = insn; | |
5f0d2358 RK |
849 | |
850 | for (insn = NEXT_INSN (insn); insn && GET_CODE (insn) == NOTE | |
851 | && NOTE_LINE_NUMBER (insn) != NOTE_INSN_BASIC_BLOCK; | |
852 | insn = NEXT_INSN (insn)) | |
853 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG) | |
854 | last = insn; | |
855 | ||
ca6c03ca JH |
856 | return last; |
857 | } | |
858 | ||
6de9cd9a DN |
859 | /* Redirect edge representing branch of (un)conditional jump or tablejump, |
860 | NULL on failure */ | |
861 | static edge | |
bc35512f | 862 | redirect_branch_edge (edge e, basic_block target) |
ca6c03ca JH |
863 | { |
864 | rtx tmp; | |
a813c111 | 865 | rtx old_label = BB_HEAD (e->dest); |
ca6c03ca | 866 | basic_block src = e->src; |
a813c111 | 867 | rtx insn = BB_END (src); |
ca6c03ca | 868 | |
ca6c03ca JH |
869 | /* We can only redirect non-fallthru edges of jump insn. */ |
870 | if (e->flags & EDGE_FALLTHRU) | |
6de9cd9a | 871 | return NULL; |
5f0d2358 | 872 | else if (GET_CODE (insn) != JUMP_INSN) |
6de9cd9a | 873 | return NULL; |
ca6c03ca JH |
874 | |
875 | /* Recognize a tablejump and adjust all matching cases. */ | |
e1233a7d | 876 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
877 | { |
878 | rtvec vec; | |
879 | int j; | |
880 | rtx new_label = block_label (target); | |
881 | ||
6ee3c8e4 | 882 | if (target == EXIT_BLOCK_PTR) |
6de9cd9a | 883 | return NULL; |
ca6c03ca JH |
884 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
885 | vec = XVEC (PATTERN (tmp), 0); | |
886 | else | |
887 | vec = XVEC (PATTERN (tmp), 1); | |
888 | ||
889 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
890 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
891 | { | |
892 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
893 | --LABEL_NUSES (old_label); | |
894 | ++LABEL_NUSES (new_label); | |
895 | } | |
896 | ||
f9da5064 | 897 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
898 | if ((tmp = single_set (insn)) != NULL |
899 | && SET_DEST (tmp) == pc_rtx | |
900 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
901 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
902 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
903 | { | |
904 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (VOIDmode, | |
905 | new_label); | |
906 | --LABEL_NUSES (old_label); | |
907 | ++LABEL_NUSES (new_label); | |
908 | } | |
909 | } | |
910 | else | |
911 | { | |
912 | /* ?? We may play the games with moving the named labels from | |
913 | one basic block to the other in case only one computed_jump is | |
914 | available. */ | |
5f0d2358 RK |
915 | if (computed_jump_p (insn) |
916 | /* A return instruction can't be redirected. */ | |
917 | || returnjump_p (insn)) | |
6de9cd9a | 918 | return NULL; |
ca6c03ca JH |
919 | |
920 | /* If the insn doesn't go where we think, we're confused. */ | |
6ee3c8e4 | 921 | if (JUMP_LABEL (insn) != old_label) |
a3623c48 | 922 | abort (); |
6ee3c8e4 JJ |
923 | |
924 | /* If the substitution doesn't succeed, die. This can happen | |
925 | if the back end emitted unrecognizable instructions or if | |
926 | target is exit block on some arches. */ | |
927 | if (!redirect_jump (insn, block_label (target), 0)) | |
928 | { | |
929 | if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 930 | return NULL; |
6ee3c8e4 JJ |
931 | abort (); |
932 | } | |
ca6c03ca JH |
933 | } |
934 | ||
c263766c RH |
935 | if (dump_file) |
936 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 937 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 938 | |
ca6c03ca | 939 | if (e->dest != target) |
6de9cd9a DN |
940 | e = redirect_edge_succ_nodup (e, target); |
941 | return e; | |
bc35512f JH |
942 | } |
943 | ||
944 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on | |
945 | expense of adding new instructions or reordering basic blocks. | |
946 | ||
947 | Function can be also called with edge destination equivalent to the TARGET. | |
948 | Then it should try the simplifications and do nothing if none is possible. | |
949 | ||
6de9cd9a DN |
950 | Return edge representing the branch if transformation succeeded. Return NULL |
951 | on failure. | |
952 | We still return NULL in case E already destinated TARGET and we didn't | |
953 | managed to simplify instruction stream. */ | |
bc35512f | 954 | |
6de9cd9a | 955 | static edge |
5671bf27 | 956 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 957 | { |
6de9cd9a | 958 | edge ret; |
f345f21a JH |
959 | basic_block src = e->src; |
960 | ||
bc35512f | 961 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 962 | return NULL; |
bc35512f | 963 | |
3348b696 | 964 | if (e->dest == target) |
6de9cd9a | 965 | return e; |
3348b696 | 966 | |
6de9cd9a | 967 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a JH |
968 | { |
969 | src->flags |= BB_DIRTY; | |
6de9cd9a | 970 | return ret; |
f345f21a | 971 | } |
bc35512f | 972 | |
6de9cd9a DN |
973 | ret = redirect_branch_edge (e, target); |
974 | if (!ret) | |
975 | return NULL; | |
5f0d2358 | 976 | |
f345f21a | 977 | src->flags |= BB_DIRTY; |
6de9cd9a | 978 | return ret; |
ca6c03ca JH |
979 | } |
980 | ||
4fe9b91c | 981 | /* Like force_nonfallthru below, but additionally performs redirection |
ca6c03ca JH |
982 | Used by redirect_edge_and_branch_force. */ |
983 | ||
cb9a1d9b | 984 | basic_block |
d329e058 | 985 | force_nonfallthru_and_redirect (edge e, basic_block target) |
ca6c03ca | 986 | { |
a3716585 | 987 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
988 | rtx note; |
989 | edge new_edge; | |
a3716585 | 990 | int abnormal_edge_flags = 0; |
ca6c03ca | 991 | |
cb9a1d9b JH |
992 | /* In the case the last instruction is conditional jump to the next |
993 | instruction, first redirect the jump itself and then continue | |
b20b352b | 994 | by creating a basic block afterwards to redirect fallthru edge. */ |
cb9a1d9b | 995 | if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR |
a813c111 | 996 | && any_condjump_p (BB_END (e->src)) |
cde1d5bf | 997 | /* When called from cfglayout, fallthru edges do not |
e0bb17a8 | 998 | necessarily go to the next block. */ |
cde1d5bf | 999 | && e->src->next_bb == e->dest |
a813c111 | 1000 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1001 | { |
1002 | rtx note; | |
58e6ae30 | 1003 | edge b = unchecked_make_edge (e->src, target, 0); |
cb9a1d9b | 1004 | |
a813c111 | 1005 | if (!redirect_jump (BB_END (e->src), block_label (target), 0)) |
cb9a1d9b | 1006 | abort (); |
a813c111 | 1007 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1008 | if (note) |
1009 | { | |
1010 | int prob = INTVAL (XEXP (note, 0)); | |
1011 | ||
1012 | b->probability = prob; | |
1013 | b->count = e->count * prob / REG_BR_PROB_BASE; | |
1014 | e->probability -= e->probability; | |
1015 | e->count -= b->count; | |
1016 | if (e->probability < 0) | |
1017 | e->probability = 0; | |
1018 | if (e->count < 0) | |
1019 | e->count = 0; | |
1020 | } | |
1021 | } | |
1022 | ||
ca6c03ca | 1023 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1024 | { |
1025 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1026 | edge. | |
1027 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1028 | one and create separate abnormal edge to original destination. |
a3716585 JH |
1029 | This allows bb-reorder to make such edge non-fallthru. */ |
1030 | if (e->dest != target) | |
1031 | abort (); | |
1032 | abnormal_edge_flags = e->flags & ~(EDGE_FALLTHRU | EDGE_CAN_FALLTHRU); | |
1033 | e->flags &= EDGE_FALLTHRU | EDGE_CAN_FALLTHRU; | |
1034 | } | |
5f0d2358 | 1035 | else if (!(e->flags & EDGE_FALLTHRU)) |
ca6c03ca | 1036 | abort (); |
24c545ff BS |
1037 | else if (e->src == ENTRY_BLOCK_PTR) |
1038 | { | |
1039 | /* We can't redirect the entry block. Create an empty block at the | |
1040 | start of the function which we use to add the new jump. */ | |
1041 | edge *pe1; | |
a813c111 | 1042 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, ENTRY_BLOCK_PTR); |
24c545ff BS |
1043 | |
1044 | /* Change the existing edge's source to be the new block, and add | |
1045 | a new edge from the entry block to the new block. */ | |
1046 | e->src = bb; | |
1047 | for (pe1 = &ENTRY_BLOCK_PTR->succ; *pe1; pe1 = &(*pe1)->succ_next) | |
1048 | if (*pe1 == e) | |
1049 | { | |
1050 | *pe1 = e->succ_next; | |
1051 | break; | |
1052 | } | |
1053 | e->succ_next = 0; | |
1054 | bb->succ = e; | |
1055 | make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU); | |
1056 | } | |
1057 | ||
a3716585 | 1058 | if (e->src->succ->succ_next || abnormal_edge_flags) |
ca6c03ca JH |
1059 | { |
1060 | /* Create the new structures. */ | |
31a78298 | 1061 | |
79019985 RH |
1062 | /* If the old block ended with a tablejump, skip its table |
1063 | by searching forward from there. Otherwise start searching | |
1064 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1065 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1066 | note = BB_END (e->src); | |
79019985 | 1067 | |
31a78298 | 1068 | /* Position the new block correctly relative to loop notes. */ |
79019985 | 1069 | note = last_loop_beg_note (note); |
31a78298 RH |
1070 | note = NEXT_INSN (note); |
1071 | ||
31a78298 | 1072 | jump_block = create_basic_block (note, NULL, e->src); |
ca6c03ca JH |
1073 | jump_block->count = e->count; |
1074 | jump_block->frequency = EDGE_FREQUENCY (e); | |
1075 | jump_block->loop_depth = target->loop_depth; | |
1076 | ||
1077 | if (target->global_live_at_start) | |
1078 | { | |
5f0d2358 RK |
1079 | jump_block->global_live_at_start |
1080 | = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
1081 | jump_block->global_live_at_end | |
1082 | = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
ca6c03ca JH |
1083 | COPY_REG_SET (jump_block->global_live_at_start, |
1084 | target->global_live_at_start); | |
1085 | COPY_REG_SET (jump_block->global_live_at_end, | |
1086 | target->global_live_at_start); | |
1087 | } | |
1088 | ||
750054a2 CT |
1089 | /* Make sure new block ends up in correct hot/cold section. */ |
1090 | ||
1091 | jump_block->partition = e->src->partition; | |
1092 | if (flag_reorder_blocks_and_partition) | |
1093 | { | |
1094 | if (e->src->partition == COLD_PARTITION) | |
1095 | { | |
1096 | rtx bb_note, new_note; | |
1097 | for (bb_note = BB_HEAD (jump_block); | |
1098 | bb_note && bb_note != NEXT_INSN (BB_END (jump_block)); | |
1099 | bb_note = NEXT_INSN (bb_note)) | |
1100 | if (GET_CODE (bb_note) == NOTE | |
1101 | && NOTE_LINE_NUMBER (bb_note) == NOTE_INSN_BASIC_BLOCK) | |
1102 | break; | |
1103 | new_note = emit_note_after (NOTE_INSN_UNLIKELY_EXECUTED_CODE, | |
1104 | bb_note); | |
1105 | NOTE_BASIC_BLOCK (new_note) = jump_block; | |
1106 | jump_block->partition = COLD_PARTITION; | |
1107 | } | |
1108 | if (GET_CODE (BB_END (jump_block)) == JUMP_INSN | |
1109 | && !any_condjump_p (BB_END (jump_block)) | |
1110 | && jump_block->succ->crossing_edge ) | |
1111 | REG_NOTES (BB_END (jump_block)) = gen_rtx_EXPR_LIST | |
1112 | (REG_CROSSING_JUMP, NULL_RTX, | |
1113 | REG_NOTES (BB_END (jump_block))); | |
1114 | } | |
1115 | ||
ca6c03ca JH |
1116 | /* Wire edge in. */ |
1117 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
1118 | new_edge->probability = e->probability; | |
1119 | new_edge->count = e->count; | |
1120 | ||
1121 | /* Redirect old edge. */ | |
1122 | redirect_edge_pred (e, jump_block); | |
1123 | e->probability = REG_BR_PROB_BASE; | |
1124 | ||
1125 | new_bb = jump_block; | |
1126 | } | |
1127 | else | |
1128 | jump_block = e->src; | |
5f0d2358 | 1129 | |
ca6c03ca JH |
1130 | e->flags &= ~EDGE_FALLTHRU; |
1131 | if (target == EXIT_BLOCK_PTR) | |
1132 | { | |
cf22ce3c | 1133 | #ifdef HAVE_return |
a813c111 | 1134 | emit_jump_insn_after (gen_return (), BB_END (jump_block)); |
cf22ce3c | 1135 | #else |
ca6c03ca | 1136 | abort (); |
cf22ce3c | 1137 | #endif |
ca6c03ca JH |
1138 | } |
1139 | else | |
1140 | { | |
1141 | rtx label = block_label (target); | |
a813c111 SB |
1142 | emit_jump_insn_after (gen_jump (label), BB_END (jump_block)); |
1143 | JUMP_LABEL (BB_END (jump_block)) = label; | |
ca6c03ca JH |
1144 | LABEL_NUSES (label)++; |
1145 | } | |
5f0d2358 | 1146 | |
a813c111 | 1147 | emit_barrier_after (BB_END (jump_block)); |
ca6c03ca JH |
1148 | redirect_edge_succ_nodup (e, target); |
1149 | ||
a3716585 JH |
1150 | if (abnormal_edge_flags) |
1151 | make_edge (src, target, abnormal_edge_flags); | |
1152 | ||
ca6c03ca JH |
1153 | return new_bb; |
1154 | } | |
1155 | ||
1156 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1157 | (and possibly create new basic block) to make edge non-fallthru. | |
1158 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1159 | |
ca6c03ca | 1160 | basic_block |
d329e058 | 1161 | force_nonfallthru (edge e) |
ca6c03ca JH |
1162 | { |
1163 | return force_nonfallthru_and_redirect (e, e->dest); | |
1164 | } | |
1165 | ||
1166 | /* Redirect edge even at the expense of creating new jump insn or | |
1167 | basic block. Return new basic block if created, NULL otherwise. | |
eaec9b3d | 1168 | Abort if conversion is impossible. */ |
ca6c03ca | 1169 | |
9ee634e3 | 1170 | static basic_block |
d329e058 | 1171 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1172 | { |
5f0d2358 RK |
1173 | if (redirect_edge_and_branch (e, target) |
1174 | || e->dest == target) | |
ca6c03ca JH |
1175 | return NULL; |
1176 | ||
1177 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1178 | and redirect newly created simplejump. */ | |
5f0d2358 | 1179 | return force_nonfallthru_and_redirect (e, target); |
ca6c03ca JH |
1180 | } |
1181 | ||
1182 | /* The given edge should potentially be a fallthru edge. If that is in | |
1183 | fact true, delete the jump and barriers that are in the way. */ | |
1184 | ||
f470c378 ZD |
1185 | static void |
1186 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1187 | { |
1188 | rtx q; | |
f470c378 ZD |
1189 | basic_block b = e->src, c = b->next_bb; |
1190 | ||
ca6c03ca JH |
1191 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1192 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
1193 | and the target label. They ought to be chastized and fixed. | |
1194 | ||
1195 | We can also wind up with a sequence of undeletable labels between | |
1196 | one block and the next. | |
1197 | ||
1198 | So search through a sequence of barriers, labels, and notes for | |
1199 | the head of block C and assert that we really do fall through. */ | |
1200 | ||
a813c111 | 1201 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1202 | if (INSN_P (q)) |
1203 | return; | |
ca6c03ca JH |
1204 | |
1205 | /* Remove what will soon cease being the jump insn from the source block. | |
1206 | If block B consisted only of this single jump, turn it into a deleted | |
1207 | note. */ | |
a813c111 | 1208 | q = BB_END (b); |
ca6c03ca JH |
1209 | if (GET_CODE (q) == JUMP_INSN |
1210 | && onlyjump_p (q) | |
1211 | && (any_uncondjump_p (q) | |
1212 | || (b->succ == e && e->succ_next == NULL))) | |
1213 | { | |
1214 | #ifdef HAVE_cc0 | |
1215 | /* If this was a conditional jump, we need to also delete | |
1216 | the insn that set cc0. */ | |
1217 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1218 | q = PREV_INSN (q); | |
1219 | #endif | |
1220 | ||
1221 | q = PREV_INSN (q); | |
1222 | ||
1223 | /* We don't want a block to end on a line-number note since that has | |
1224 | the potential of changing the code between -g and not -g. */ | |
1225 | while (GET_CODE (q) == NOTE && NOTE_LINE_NUMBER (q) >= 0) | |
1226 | q = PREV_INSN (q); | |
1227 | } | |
1228 | ||
1229 | /* Selectively unlink the sequence. */ | |
a813c111 SB |
1230 | if (q != PREV_INSN (BB_HEAD (c))) |
1231 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c))); | |
ca6c03ca JH |
1232 | |
1233 | e->flags |= EDGE_FALLTHRU; | |
1234 | } | |
ca6c03ca JH |
1235 | \f |
1236 | /* Helper function for split_edge. Return true in case edge BB2 to BB1 | |
1237 | is back edge of syntactic loop. */ | |
1238 | ||
1239 | static bool | |
d329e058 | 1240 | back_edge_of_syntactic_loop_p (basic_block bb1, basic_block bb2) |
ca6c03ca JH |
1241 | { |
1242 | rtx insn; | |
1243 | int count = 0; | |
bf77398c | 1244 | basic_block bb; |
ca6c03ca | 1245 | |
bf77398c | 1246 | if (bb1 == bb2) |
0b17ab2f | 1247 | return true; |
355e4ec4 | 1248 | |
bf77398c ZD |
1249 | /* ??? Could we guarantee that bb indices are monotone, so that we could |
1250 | just compare them? */ | |
1251 | for (bb = bb1; bb && bb != bb2; bb = bb->next_bb) | |
1252 | continue; | |
1253 | ||
1254 | if (!bb) | |
1255 | return false; | |
1256 | ||
a813c111 | 1257 | for (insn = BB_END (bb1); insn != BB_HEAD (bb2) && count >= 0; |
ca6c03ca JH |
1258 | insn = NEXT_INSN (insn)) |
1259 | if (GET_CODE (insn) == NOTE) | |
1260 | { | |
1261 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG) | |
1262 | count++; | |
5f0d2358 | 1263 | else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END) |
ca6c03ca JH |
1264 | count--; |
1265 | } | |
1266 | ||
1267 | return count >= 0; | |
1268 | } | |
1269 | ||
f470c378 ZD |
1270 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1271 | ||
1272 | static bool | |
1273 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1274 | basic_block after ATTRIBUTE_UNUSED) | |
1275 | { | |
1276 | return false; | |
1277 | } | |
1278 | ||
ca6c03ca JH |
1279 | /* Split a (typically critical) edge. Return the new block. |
1280 | Abort on abnormal edges. | |
1281 | ||
1282 | ??? The code generally expects to be called on critical edges. | |
1283 | The case of a block ending in an unconditional jump to a | |
1284 | block with multiple predecessors is not handled optimally. */ | |
1285 | ||
8ce33230 | 1286 | static basic_block |
d329e058 | 1287 | rtl_split_edge (edge edge_in) |
ca6c03ca JH |
1288 | { |
1289 | basic_block bb; | |
ca6c03ca JH |
1290 | rtx before; |
1291 | ||
1292 | /* Abnormal edges cannot be split. */ | |
1293 | if ((edge_in->flags & EDGE_ABNORMAL) != 0) | |
1294 | abort (); | |
1295 | ||
1296 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1297 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1298 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1299 | { | |
1300 | edge e; | |
5f0d2358 | 1301 | |
ca6c03ca JH |
1302 | for (e = edge_in->dest->pred; e; e = e->pred_next) |
1303 | if (e->flags & EDGE_FALLTHRU) | |
1304 | break; | |
1305 | ||
1306 | if (e) | |
1307 | force_nonfallthru (e); | |
1308 | } | |
1309 | ||
1310 | /* Create the basic block note. | |
1311 | ||
f63d1bf7 | 1312 | Where we place the note can have a noticeable impact on the generated |
ca6c03ca JH |
1313 | code. Consider this cfg: |
1314 | ||
1315 | E | |
1316 | | | |
1317 | 0 | |
1318 | / \ | |
1319 | +->1-->2--->E | |
1320 | | | | |
1321 | +--+ | |
1322 | ||
1323 | If we need to insert an insn on the edge from block 0 to block 1, | |
1324 | we want to ensure the instructions we insert are outside of any | |
1325 | loop notes that physically sit between block 0 and block 1. Otherwise | |
1326 | we confuse the loop optimizer into thinking the loop is a phony. */ | |
1327 | ||
1328 | if (edge_in->dest != EXIT_BLOCK_PTR | |
a813c111 SB |
1329 | && PREV_INSN (BB_HEAD (edge_in->dest)) |
1330 | && GET_CODE (PREV_INSN (BB_HEAD (edge_in->dest))) == NOTE | |
1331 | && (NOTE_LINE_NUMBER (PREV_INSN (BB_HEAD (edge_in->dest))) | |
5f0d2358 | 1332 | == NOTE_INSN_LOOP_BEG) |
ca6c03ca | 1333 | && !back_edge_of_syntactic_loop_p (edge_in->dest, edge_in->src)) |
a813c111 | 1334 | before = PREV_INSN (BB_HEAD (edge_in->dest)); |
ca6c03ca | 1335 | else if (edge_in->dest != EXIT_BLOCK_PTR) |
a813c111 | 1336 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1337 | else |
1338 | before = NULL_RTX; | |
1339 | ||
918ed612 | 1340 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); |
ca6c03ca JH |
1341 | |
1342 | /* ??? This info is likely going to be out of date very soon. */ | |
1343 | if (edge_in->dest->global_live_at_start) | |
1344 | { | |
1345 | bb->global_live_at_start = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
1346 | bb->global_live_at_end = OBSTACK_ALLOC_REG_SET (&flow_obstack); | |
5f0d2358 RK |
1347 | COPY_REG_SET (bb->global_live_at_start, |
1348 | edge_in->dest->global_live_at_start); | |
1349 | COPY_REG_SET (bb->global_live_at_end, | |
1350 | edge_in->dest->global_live_at_start); | |
ca6c03ca JH |
1351 | } |
1352 | ||
4977bab6 | 1353 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1354 | |
4d6922ee | 1355 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1356 | jump instruction to target our new block. */ |
1357 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1358 | { | |
1359 | if (!redirect_edge_and_branch (edge_in, bb)) | |
1360 | abort (); | |
1361 | } | |
1362 | else | |
1363 | redirect_edge_succ (edge_in, bb); | |
1364 | ||
1365 | return bb; | |
1366 | } | |
1367 | ||
1368 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1369 | The new instructions and basic blocks (if any) will not appear in the | |
1370 | CFG until commit_edge_insertions is called. */ | |
1371 | ||
1372 | void | |
d329e058 | 1373 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1374 | { |
1375 | /* We cannot insert instructions on an abnormal critical edge. | |
1376 | It will be easier to find the culprit if we die now. */ | |
1377 | if ((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)) | |
1378 | abort (); | |
1379 | ||
6de9cd9a | 1380 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1381 | start_sequence (); |
1382 | else | |
6de9cd9a | 1383 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1384 | |
1385 | emit_insn (pattern); | |
1386 | ||
6de9cd9a | 1387 | e->insns.r = get_insns (); |
ca6c03ca JH |
1388 | end_sequence (); |
1389 | } | |
1390 | ||
ff25ef99 ZD |
1391 | /* Called from safe_insert_insn_on_edge through note_stores, marks live |
1392 | registers that are killed by the store. */ | |
1393 | static void | |
1394 | mark_killed_regs (rtx reg, rtx set ATTRIBUTE_UNUSED, void *data) | |
1395 | { | |
1396 | regset killed = data; | |
1397 | int regno, i; | |
1398 | ||
1399 | if (GET_CODE (reg) == SUBREG) | |
1400 | reg = SUBREG_REG (reg); | |
1401 | if (!REG_P (reg)) | |
1402 | return; | |
1403 | regno = REGNO (reg); | |
1404 | if (regno >= FIRST_PSEUDO_REGISTER) | |
1405 | SET_REGNO_REG_SET (killed, regno); | |
1406 | else | |
1407 | { | |
66fd46b6 | 1408 | for (i = 0; i < (int) hard_regno_nregs[regno][GET_MODE (reg)]; i++) |
ff25ef99 ZD |
1409 | SET_REGNO_REG_SET (killed, regno + i); |
1410 | } | |
1411 | } | |
1412 | ||
1413 | /* Similar to insert_insn_on_edge, tries to put INSN to edge E. Additionally | |
1414 | it checks whether this will not clobber the registers that are live on the | |
e0bb17a8 | 1415 | edge (i.e. it requires liveness information to be up-to-date) and if there |
ff25ef99 | 1416 | are some, then it tries to save and restore them. Returns true if |
e0bb17a8 | 1417 | successful. */ |
ff25ef99 ZD |
1418 | bool |
1419 | safe_insert_insn_on_edge (rtx insn, edge e) | |
1420 | { | |
1421 | rtx x; | |
1422 | regset_head killed_head; | |
1423 | regset killed = INITIALIZE_REG_SET (killed_head); | |
1424 | rtx save_regs = NULL_RTX; | |
1425 | int regno, noccmode; | |
1426 | enum machine_mode mode; | |
1427 | ||
1428 | #ifdef AVOID_CCMODE_COPIES | |
1429 | noccmode = true; | |
1430 | #else | |
1431 | noccmode = false; | |
1432 | #endif | |
1433 | ||
1434 | for (x = insn; x; x = NEXT_INSN (x)) | |
1435 | if (INSN_P (x)) | |
1436 | note_stores (PATTERN (x), mark_killed_regs, killed); | |
1437 | bitmap_operation (killed, killed, e->dest->global_live_at_start, | |
1438 | BITMAP_AND); | |
1439 | ||
1440 | EXECUTE_IF_SET_IN_REG_SET (killed, 0, regno, | |
1441 | { | |
1442 | mode = regno < FIRST_PSEUDO_REGISTER | |
1443 | ? reg_raw_mode[regno] | |
1444 | : GET_MODE (regno_reg_rtx[regno]); | |
1445 | if (mode == VOIDmode) | |
1446 | return false; | |
1447 | ||
1448 | if (noccmode && mode == CCmode) | |
1449 | return false; | |
1450 | ||
1451 | save_regs = alloc_EXPR_LIST (0, | |
1452 | alloc_EXPR_LIST (0, | |
1453 | gen_reg_rtx (mode), | |
1454 | gen_raw_REG (mode, regno)), | |
1455 | save_regs); | |
1456 | }); | |
1457 | ||
1458 | if (save_regs) | |
1459 | { | |
1460 | rtx from, to; | |
1461 | ||
1462 | start_sequence (); | |
1463 | for (x = save_regs; x; x = XEXP (x, 1)) | |
1464 | { | |
1465 | from = XEXP (XEXP (x, 0), 1); | |
1466 | to = XEXP (XEXP (x, 0), 0); | |
1467 | emit_move_insn (to, from); | |
1468 | } | |
1469 | emit_insn (insn); | |
1470 | for (x = save_regs; x; x = XEXP (x, 1)) | |
1471 | { | |
1472 | from = XEXP (XEXP (x, 0), 0); | |
1473 | to = XEXP (XEXP (x, 0), 1); | |
1474 | emit_move_insn (to, from); | |
1475 | } | |
1476 | insn = get_insns (); | |
1477 | end_sequence (); | |
1478 | free_EXPR_LIST_list (&save_regs); | |
1479 | } | |
1480 | insert_insn_on_edge (insn, e); | |
1481 | ||
1482 | FREE_REG_SET (killed); | |
1483 | return true; | |
1484 | } | |
1485 | ||
ca6c03ca JH |
1486 | /* Update the CFG for the instructions queued on edge E. */ |
1487 | ||
1488 | static void | |
d329e058 | 1489 | commit_one_edge_insertion (edge e, int watch_calls) |
ca6c03ca JH |
1490 | { |
1491 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
eae4bc56 | 1492 | basic_block bb = NULL; |
ca6c03ca JH |
1493 | |
1494 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1495 | insns = e->insns.r; |
1496 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1497 | |
3dec4024 JH |
1498 | /* Special case -- avoid inserting code between call and storing |
1499 | its return value. */ | |
1500 | if (watch_calls && (e->flags & EDGE_FALLTHRU) && !e->dest->pred->pred_next | |
1501 | && e->src != ENTRY_BLOCK_PTR | |
a813c111 | 1502 | && GET_CODE (BB_END (e->src)) == CALL_INSN) |
ca6c03ca | 1503 | { |
a813c111 | 1504 | rtx next = next_nonnote_insn (BB_END (e->src)); |
ca6c03ca | 1505 | |
a813c111 | 1506 | after = BB_HEAD (e->dest); |
3dec4024 JH |
1507 | /* The first insn after the call may be a stack pop, skip it. */ |
1508 | while (next | |
1509 | && keep_with_call_p (next)) | |
f87c27b4 KH |
1510 | { |
1511 | after = next; | |
3dec4024 JH |
1512 | next = next_nonnote_insn (next); |
1513 | } | |
1514 | bb = e->dest; | |
ca6c03ca | 1515 | } |
3dec4024 | 1516 | if (!before && !after) |
ca6c03ca | 1517 | { |
3dec4024 JH |
1518 | /* Figure out where to put these things. If the destination has |
1519 | one predecessor, insert there. Except for the exit block. */ | |
1520 | if (e->dest->pred->pred_next == NULL && e->dest != EXIT_BLOCK_PTR) | |
ca6c03ca | 1521 | { |
3dec4024 JH |
1522 | bb = e->dest; |
1523 | ||
1524 | /* Get the location correct wrt a code label, and "nice" wrt | |
1525 | a basic block note, and before everything else. */ | |
a813c111 | 1526 | tmp = BB_HEAD (bb); |
3dec4024 JH |
1527 | if (GET_CODE (tmp) == CODE_LABEL) |
1528 | tmp = NEXT_INSN (tmp); | |
1529 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1530 | tmp = NEXT_INSN (tmp); | |
750054a2 CT |
1531 | if (tmp |
1532 | && GET_CODE (tmp) == NOTE | |
1533 | && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_UNLIKELY_EXECUTED_CODE) | |
1534 | tmp = NEXT_INSN (tmp); | |
a813c111 | 1535 | if (tmp == BB_HEAD (bb)) |
3dec4024 JH |
1536 | before = tmp; |
1537 | else if (tmp) | |
1538 | after = PREV_INSN (tmp); | |
1539 | else | |
1540 | after = get_last_insn (); | |
1541 | } | |
1542 | ||
1543 | /* If the source has one successor and the edge is not abnormal, | |
1544 | insert there. Except for the entry block. */ | |
1545 | else if ((e->flags & EDGE_ABNORMAL) == 0 | |
1546 | && e->src->succ->succ_next == NULL | |
1547 | && e->src != ENTRY_BLOCK_PTR) | |
1548 | { | |
1549 | bb = e->src; | |
1550 | ||
1551 | /* It is possible to have a non-simple jump here. Consider a target | |
1552 | where some forms of unconditional jumps clobber a register. This | |
1553 | happens on the fr30 for example. | |
1554 | ||
1555 | We know this block has a single successor, so we can just emit | |
1556 | the queued insns before the jump. */ | |
a813c111 SB |
1557 | if (GET_CODE (BB_END (bb)) == JUMP_INSN) |
1558 | for (before = BB_END (bb); | |
3dec4024 JH |
1559 | GET_CODE (PREV_INSN (before)) == NOTE |
1560 | && NOTE_LINE_NUMBER (PREV_INSN (before)) == | |
1561 | NOTE_INSN_LOOP_BEG; before = PREV_INSN (before)) | |
1562 | ; | |
1563 | else | |
1564 | { | |
1565 | /* We'd better be fallthru, or we've lost track of what's what. */ | |
1566 | if ((e->flags & EDGE_FALLTHRU) == 0) | |
1567 | abort (); | |
ca6c03ca | 1568 | |
a813c111 | 1569 | after = BB_END (bb); |
3dec4024 JH |
1570 | } |
1571 | } | |
1572 | /* Otherwise we must split the edge. */ | |
1573 | else | |
1574 | { | |
1575 | bb = split_edge (e); | |
a813c111 | 1576 | after = BB_END (bb); |
750054a2 CT |
1577 | |
1578 | /* If we are partitioning hot/cold basic blocks, we must make sure | |
1579 | that the new basic block ends up in the correct section. */ | |
1580 | ||
1581 | bb->partition = e->src->partition; | |
1582 | if (flag_reorder_blocks_and_partition | |
1583 | && e->src != ENTRY_BLOCK_PTR | |
1584 | && e->src->partition == COLD_PARTITION) | |
1585 | { | |
1586 | rtx bb_note, new_note, cur_insn; | |
1587 | ||
1588 | bb_note = NULL_RTX; | |
1589 | for (cur_insn = BB_HEAD (bb); cur_insn != NEXT_INSN (BB_END (bb)); | |
1590 | cur_insn = NEXT_INSN (cur_insn)) | |
1591 | if (GET_CODE (cur_insn) == NOTE | |
1592 | && NOTE_LINE_NUMBER (cur_insn) == NOTE_INSN_BASIC_BLOCK) | |
1593 | { | |
1594 | bb_note = cur_insn; | |
1595 | break; | |
1596 | } | |
1597 | ||
1598 | new_note = emit_note_after (NOTE_INSN_UNLIKELY_EXECUTED_CODE, | |
1599 | bb_note); | |
1600 | NOTE_BASIC_BLOCK (new_note) = bb; | |
1601 | if (GET_CODE (BB_END (bb)) == JUMP_INSN | |
1602 | && !any_condjump_p (BB_END (bb)) | |
1603 | && bb->succ->crossing_edge ) | |
1604 | REG_NOTES (BB_END (bb)) = gen_rtx_EXPR_LIST | |
1605 | (REG_CROSSING_JUMP, NULL_RTX, REG_NOTES (BB_END (bb))); | |
1606 | if (after == bb_note) | |
1607 | after = new_note; | |
1608 | } | |
ca6c03ca JH |
1609 | } |
1610 | } | |
1611 | ||
ca6c03ca JH |
1612 | /* Now that we've found the spot, do the insertion. */ |
1613 | ||
1614 | if (before) | |
1615 | { | |
2f937369 | 1616 | emit_insn_before (insns, before); |
ca6c03ca JH |
1617 | last = prev_nonnote_insn (before); |
1618 | } | |
1619 | else | |
2f937369 | 1620 | last = emit_insn_after (insns, after); |
ca6c03ca JH |
1621 | |
1622 | if (returnjump_p (last)) | |
1623 | { | |
1624 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
1625 | This is not currently a problem because this only happens | |
3dec4024 JH |
1626 | for the (single) epilogue, which already has a fallthru edge |
1627 | to EXIT. */ | |
ca6c03ca JH |
1628 | |
1629 | e = bb->succ; | |
1630 | if (e->dest != EXIT_BLOCK_PTR | |
3dec4024 | 1631 | || e->succ_next != NULL || (e->flags & EDGE_FALLTHRU) == 0) |
ca6c03ca | 1632 | abort (); |
ca6c03ca | 1633 | |
5f0d2358 | 1634 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 1635 | emit_barrier_after (last); |
0b17ab2f | 1636 | |
ca6c03ca JH |
1637 | if (before) |
1638 | delete_insn (before); | |
1639 | } | |
1640 | else if (GET_CODE (last) == JUMP_INSN) | |
1641 | abort (); | |
5f0d2358 | 1642 | |
9dca2ad5 JH |
1643 | /* Mark the basic block for find_sub_basic_blocks. */ |
1644 | bb->aux = &bb->aux; | |
ca6c03ca JH |
1645 | } |
1646 | ||
1647 | /* Update the CFG for all queued instructions. */ | |
1648 | ||
1649 | void | |
d329e058 | 1650 | commit_edge_insertions (void) |
ca6c03ca | 1651 | { |
ca6c03ca | 1652 | basic_block bb; |
9dca2ad5 | 1653 | sbitmap blocks; |
9809a362 | 1654 | bool changed = false; |
ca6c03ca JH |
1655 | |
1656 | #ifdef ENABLE_CHECKING | |
1657 | verify_flow_info (); | |
1658 | #endif | |
1659 | ||
e0082a72 | 1660 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
ca6c03ca JH |
1661 | { |
1662 | edge e, next; | |
1663 | ||
1664 | for (e = bb->succ; e; e = next) | |
1665 | { | |
1666 | next = e->succ_next; | |
6de9cd9a | 1667 | if (e->insns.r) |
9809a362 | 1668 | { |
6de9cd9a DN |
1669 | changed = true; |
1670 | commit_one_edge_insertion (e, false); | |
9809a362 | 1671 | } |
3dec4024 | 1672 | } |
3dec4024 | 1673 | } |
9dca2ad5 | 1674 | |
9809a362 JH |
1675 | if (!changed) |
1676 | return; | |
1677 | ||
9dca2ad5 JH |
1678 | blocks = sbitmap_alloc (last_basic_block); |
1679 | sbitmap_zero (blocks); | |
1680 | FOR_EACH_BB (bb) | |
1681 | if (bb->aux) | |
1682 | { | |
1683 | SET_BIT (blocks, bb->index); | |
1684 | /* Check for forgotten bb->aux values before commit_edge_insertions | |
1685 | call. */ | |
1686 | if (bb->aux != &bb->aux) | |
1687 | abort (); | |
1688 | bb->aux = NULL; | |
1689 | } | |
1690 | find_many_sub_basic_blocks (blocks); | |
1691 | sbitmap_free (blocks); | |
3dec4024 JH |
1692 | } |
1693 | \f | |
1694 | /* Update the CFG for all queued instructions, taking special care of inserting | |
1695 | code on edges between call and storing its return value. */ | |
1696 | ||
1697 | void | |
d329e058 | 1698 | commit_edge_insertions_watch_calls (void) |
3dec4024 | 1699 | { |
3dec4024 | 1700 | basic_block bb; |
9809a362 JH |
1701 | sbitmap blocks; |
1702 | bool changed = false; | |
3dec4024 JH |
1703 | |
1704 | #ifdef ENABLE_CHECKING | |
1705 | verify_flow_info (); | |
1706 | #endif | |
1707 | ||
e0082a72 | 1708 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
3dec4024 JH |
1709 | { |
1710 | edge e, next; | |
1711 | ||
1712 | for (e = bb->succ; e; e = next) | |
1713 | { | |
1714 | next = e->succ_next; | |
6de9cd9a | 1715 | if (e->insns.r) |
9809a362 JH |
1716 | { |
1717 | changed = true; | |
1718 | commit_one_edge_insertion (e, true); | |
1719 | } | |
ca6c03ca | 1720 | } |
ca6c03ca | 1721 | } |
9809a362 JH |
1722 | |
1723 | if (!changed) | |
1724 | return; | |
1725 | ||
1726 | blocks = sbitmap_alloc (last_basic_block); | |
1727 | sbitmap_zero (blocks); | |
1728 | FOR_EACH_BB (bb) | |
1729 | if (bb->aux) | |
1730 | { | |
1731 | SET_BIT (blocks, bb->index); | |
1732 | /* Check for forgotten bb->aux values before commit_edge_insertions | |
1733 | call. */ | |
1734 | if (bb->aux != &bb->aux) | |
1735 | abort (); | |
1736 | bb->aux = NULL; | |
1737 | } | |
1738 | find_many_sub_basic_blocks (blocks); | |
1739 | sbitmap_free (blocks); | |
ca6c03ca JH |
1740 | } |
1741 | \f | |
f470c378 ZD |
1742 | /* Print out RTL-specific basic block information (live information |
1743 | at start and end). */ | |
ca6c03ca | 1744 | |
10e9fecc | 1745 | static void |
f470c378 | 1746 | rtl_dump_bb (basic_block bb, FILE *outf, int indent) |
ca6c03ca JH |
1747 | { |
1748 | rtx insn; | |
1749 | rtx last; | |
f470c378 | 1750 | char *s_indent; |
ca6c03ca | 1751 | |
400e39e3 KH |
1752 | s_indent = alloca ((size_t) indent + 1); |
1753 | memset (s_indent, ' ', (size_t) indent); | |
f470c378 ZD |
1754 | s_indent[indent] = '\0'; |
1755 | ||
1756 | fprintf (outf, ";;%s Registers live at start: ", s_indent); | |
ca6c03ca JH |
1757 | dump_regset (bb->global_live_at_start, outf); |
1758 | putc ('\n', outf); | |
1759 | ||
a813c111 | 1760 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; |
ca6c03ca JH |
1761 | insn = NEXT_INSN (insn)) |
1762 | print_rtl_single (outf, insn); | |
1763 | ||
f470c378 | 1764 | fprintf (outf, ";;%s Registers live at end: ", s_indent); |
ca6c03ca JH |
1765 | dump_regset (bb->global_live_at_end, outf); |
1766 | putc ('\n', outf); | |
ca6c03ca JH |
1767 | } |
1768 | \f | |
1769 | /* Like print_rtl, but also print out live information for the start of each | |
1770 | basic block. */ | |
1771 | ||
1772 | void | |
d329e058 | 1773 | print_rtl_with_bb (FILE *outf, rtx rtx_first) |
ca6c03ca | 1774 | { |
b3694847 | 1775 | rtx tmp_rtx; |
ca6c03ca JH |
1776 | |
1777 | if (rtx_first == 0) | |
1778 | fprintf (outf, "(nil)\n"); | |
1779 | else | |
1780 | { | |
ca6c03ca JH |
1781 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
1782 | int max_uid = get_max_uid (); | |
703ad42b KG |
1783 | basic_block *start = xcalloc (max_uid, sizeof (basic_block)); |
1784 | basic_block *end = xcalloc (max_uid, sizeof (basic_block)); | |
1785 | enum bb_state *in_bb_p = xcalloc (max_uid, sizeof (enum bb_state)); | |
ca6c03ca | 1786 | |
e0082a72 ZD |
1787 | basic_block bb; |
1788 | ||
1789 | FOR_EACH_BB_REVERSE (bb) | |
ca6c03ca | 1790 | { |
ca6c03ca JH |
1791 | rtx x; |
1792 | ||
a813c111 SB |
1793 | start[INSN_UID (BB_HEAD (bb))] = bb; |
1794 | end[INSN_UID (BB_END (bb))] = bb; | |
1795 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
ca6c03ca JH |
1796 | { |
1797 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 1798 | |
ca6c03ca JH |
1799 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
1800 | state = IN_ONE_BB; | |
1801 | in_bb_p[INSN_UID (x)] = state; | |
1802 | ||
a813c111 | 1803 | if (x == BB_END (bb)) |
ca6c03ca JH |
1804 | break; |
1805 | } | |
1806 | } | |
1807 | ||
1808 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
1809 | { | |
1810 | int did_output; | |
ca6c03ca JH |
1811 | |
1812 | if ((bb = start[INSN_UID (tmp_rtx)]) != NULL) | |
1813 | { | |
1814 | fprintf (outf, ";; Start of basic block %d, registers live:", | |
0b17ab2f | 1815 | bb->index); |
ca6c03ca JH |
1816 | dump_regset (bb->global_live_at_start, outf); |
1817 | putc ('\n', outf); | |
1818 | } | |
1819 | ||
1820 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB | |
1821 | && GET_CODE (tmp_rtx) != NOTE | |
1822 | && GET_CODE (tmp_rtx) != BARRIER) | |
1823 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
1824 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
1825 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
1826 | ||
1827 | did_output = print_rtl_single (outf, tmp_rtx); | |
1828 | ||
1829 | if ((bb = end[INSN_UID (tmp_rtx)]) != NULL) | |
1830 | { | |
1831 | fprintf (outf, ";; End of basic block %d, registers live:\n", | |
0b17ab2f | 1832 | bb->index); |
ca6c03ca JH |
1833 | dump_regset (bb->global_live_at_end, outf); |
1834 | putc ('\n', outf); | |
1835 | } | |
1836 | ||
1837 | if (did_output) | |
1838 | putc ('\n', outf); | |
1839 | } | |
1840 | ||
1841 | free (start); | |
1842 | free (end); | |
1843 | free (in_bb_p); | |
1844 | } | |
1845 | ||
1846 | if (current_function_epilogue_delay_list != 0) | |
1847 | { | |
1848 | fprintf (outf, "\n;; Insns in epilogue delay list:\n\n"); | |
1849 | for (tmp_rtx = current_function_epilogue_delay_list; tmp_rtx != 0; | |
1850 | tmp_rtx = XEXP (tmp_rtx, 1)) | |
1851 | print_rtl_single (outf, XEXP (tmp_rtx, 0)); | |
1852 | } | |
1853 | } | |
1854 | \f | |
b446e5a2 | 1855 | void |
d329e058 | 1856 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
1857 | { |
1858 | rtx note; | |
a813c111 | 1859 | if (GET_CODE (BB_END (bb)) != JUMP_INSN) |
b446e5a2 | 1860 | return; |
a813c111 | 1861 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
b446e5a2 JH |
1862 | if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability) |
1863 | return; | |
1864 | XEXP (note, 0) = GEN_INT (BRANCH_EDGE (bb)->probability); | |
1865 | } | |
1866 | \f | |
10e9fecc JH |
1867 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
1868 | cfglayout RTL. | |
ca6c03ca JH |
1869 | |
1870 | Currently it does following checks: | |
1871 | ||
1872 | - test head/end pointers | |
1873 | - overlapping of basic blocks | |
ca6c03ca | 1874 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) |
f63d1bf7 | 1875 | - tails of basic blocks (ensure that boundary is necessary) |
ca6c03ca JH |
1876 | - scans body of the basic block for JUMP_INSN, CODE_LABEL |
1877 | and NOTE_INSN_BASIC_BLOCK | |
750054a2 | 1878 | - verify that no fall_thru edge crosses hot/cold partition boundaries |
ca6c03ca JH |
1879 | |
1880 | In future it can be extended check a lot of other stuff as well | |
1881 | (reachability of basic blocks, life information, etc. etc.). */ | |
f470c378 | 1882 | |
10e9fecc | 1883 | static int |
d329e058 | 1884 | rtl_verify_flow_info_1 (void) |
ca6c03ca JH |
1885 | { |
1886 | const int max_uid = get_max_uid (); | |
ca6c03ca | 1887 | rtx last_head = get_last_insn (); |
10e9fecc | 1888 | basic_block *bb_info; |
ca6c03ca | 1889 | rtx x; |
10e9fecc | 1890 | int err = 0; |
918ed612 | 1891 | basic_block bb, last_bb_seen; |
ca6c03ca | 1892 | |
703ad42b | 1893 | bb_info = xcalloc (max_uid, sizeof (basic_block)); |
ca6c03ca | 1894 | |
918ed612 ZD |
1895 | /* Check bb chain & numbers. */ |
1896 | last_bb_seen = ENTRY_BLOCK_PTR; | |
918ed612 | 1897 | |
e0082a72 | 1898 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1899 | { |
a813c111 SB |
1900 | rtx head = BB_HEAD (bb); |
1901 | rtx end = BB_END (bb); | |
ca6c03ca JH |
1902 | |
1903 | /* Verify the end of the basic block is in the INSN chain. */ | |
1904 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) | |
1905 | if (x == end) | |
1906 | break; | |
5f0d2358 | 1907 | |
ca6c03ca JH |
1908 | if (!x) |
1909 | { | |
1f978f5f | 1910 | error ("end insn %d for block %d not found in the insn stream", |
0b17ab2f | 1911 | INSN_UID (end), bb->index); |
ca6c03ca JH |
1912 | err = 1; |
1913 | } | |
1914 | ||
1915 | /* Work backwards from the end to the head of the basic block | |
1916 | to verify the head is in the RTL chain. */ | |
1917 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
1918 | { | |
1919 | /* While walking over the insn chain, verify insns appear | |
1920 | in only one basic block and initialize the BB_INFO array | |
1921 | used by other passes. */ | |
1922 | if (bb_info[INSN_UID (x)] != NULL) | |
1923 | { | |
1f978f5f | 1924 | error ("insn %d is in multiple basic blocks (%d and %d)", |
0b17ab2f | 1925 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); |
ca6c03ca JH |
1926 | err = 1; |
1927 | } | |
5f0d2358 | 1928 | |
ca6c03ca JH |
1929 | bb_info[INSN_UID (x)] = bb; |
1930 | ||
1931 | if (x == head) | |
1932 | break; | |
1933 | } | |
1934 | if (!x) | |
1935 | { | |
1f978f5f | 1936 | error ("head insn %d for block %d not found in the insn stream", |
0b17ab2f | 1937 | INSN_UID (head), bb->index); |
ca6c03ca JH |
1938 | err = 1; |
1939 | } | |
1940 | ||
1941 | last_head = x; | |
1942 | } | |
1943 | ||
1944 | /* Now check the basic blocks (boundaries etc.) */ | |
e0082a72 | 1945 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1946 | { |
3dec4024 | 1947 | int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0; |
3cf54412 | 1948 | edge e, fallthru = NULL; |
5a1a3e5e | 1949 | rtx note; |
ca6c03ca | 1950 | |
a813c111 SB |
1951 | if (INSN_P (BB_END (bb)) |
1952 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) | |
3e638a90 | 1953 | && bb->succ && bb->succ->succ_next |
a813c111 | 1954 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 1955 | { |
5a1a3e5e JH |
1956 | if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability) |
1957 | { | |
0108ae51 | 1958 | error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i", |
5a1a3e5e JH |
1959 | INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability); |
1960 | err = 1; | |
1961 | } | |
1962 | } | |
5f0d2358 | 1963 | for (e = bb->succ; e; e = e->succ_next) |
ca6c03ca | 1964 | { |
ca6c03ca | 1965 | if (e->flags & EDGE_FALLTHRU) |
750054a2 CT |
1966 | { |
1967 | n_fallthru++, fallthru = e; | |
1968 | if (e->crossing_edge) | |
1969 | { | |
1970 | error ("Fallthru edge crosses section boundary (bb %i)", | |
1971 | e->src->index); | |
1972 | err = 1; | |
1973 | } | |
1974 | } | |
3dec4024 | 1975 | |
65f43cdf ZD |
1976 | if ((e->flags & ~(EDGE_DFS_BACK |
1977 | | EDGE_CAN_FALLTHRU | |
1978 | | EDGE_IRREDUCIBLE_LOOP | |
1979 | | EDGE_LOOP_EXIT)) == 0) | |
3dec4024 JH |
1980 | n_branch++; |
1981 | ||
1982 | if (e->flags & EDGE_ABNORMAL_CALL) | |
1983 | n_call++; | |
1984 | ||
1985 | if (e->flags & EDGE_EH) | |
1986 | n_eh++; | |
1987 | else if (e->flags & EDGE_ABNORMAL) | |
1988 | n_abnormal++; | |
ca6c03ca | 1989 | } |
5f0d2358 | 1990 | |
a813c111 SB |
1991 | if (n_eh && GET_CODE (PATTERN (BB_END (bb))) != RESX |
1992 | && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) | |
3dec4024 | 1993 | { |
0b17ab2f | 1994 | error ("Missing REG_EH_REGION note in the end of bb %i", bb->index); |
3dec4024 JH |
1995 | err = 1; |
1996 | } | |
1997 | if (n_branch | |
a813c111 SB |
1998 | && (GET_CODE (BB_END (bb)) != JUMP_INSN |
1999 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) | |
2000 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2001 | { |
0b17ab2f | 2002 | error ("Too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
2003 | err = 1; |
2004 | } | |
a813c111 | 2005 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2006 | { |
0b17ab2f | 2007 | error ("Fallthru edge after unconditional jump %i", bb->index); |
3dec4024 JH |
2008 | err = 1; |
2009 | } | |
a813c111 | 2010 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2011 | { |
0b17ab2f | 2012 | error ("Wrong amount of branch edges after unconditional jump %i", bb->index); |
3dec4024 JH |
2013 | err = 1; |
2014 | } | |
a813c111 SB |
2015 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
2016 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) | |
3dec4024 | 2017 | { |
0b17ab2f | 2018 | error ("Wrong amount of branch edges after conditional jump %i", bb->index); |
3dec4024 JH |
2019 | err = 1; |
2020 | } | |
a813c111 | 2021 | if (n_call && GET_CODE (BB_END (bb)) != CALL_INSN) |
3dec4024 | 2022 | { |
0b17ab2f | 2023 | error ("Call edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
2024 | err = 1; |
2025 | } | |
2026 | if (n_abnormal | |
a813c111 SB |
2027 | && (GET_CODE (BB_END (bb)) != CALL_INSN && n_call != n_abnormal) |
2028 | && (GET_CODE (BB_END (bb)) != JUMP_INSN | |
2029 | || any_condjump_p (BB_END (bb)) | |
2030 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2031 | { |
0b17ab2f | 2032 | error ("Abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
2033 | err = 1; |
2034 | } | |
f87c27b4 | 2035 | |
a813c111 | 2036 | for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x)) |
ba4f7968 | 2037 | if (BLOCK_FOR_INSN (x) != bb) |
5f0d2358 RK |
2038 | { |
2039 | debug_rtx (x); | |
2040 | if (! BLOCK_FOR_INSN (x)) | |
2041 | error | |
2042 | ("insn %d inside basic block %d but block_for_insn is NULL", | |
0b17ab2f | 2043 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2044 | else |
2045 | error | |
2046 | ("insn %d inside basic block %d but block_for_insn is %i", | |
0b17ab2f | 2047 | INSN_UID (x), bb->index, BLOCK_FOR_INSN (x)->index); |
5f0d2358 RK |
2048 | |
2049 | err = 1; | |
2050 | } | |
ca6c03ca JH |
2051 | |
2052 | /* OK pointers are correct. Now check the header of basic | |
2053 | block. It ought to contain optional CODE_LABEL followed | |
2054 | by NOTE_BASIC_BLOCK. */ | |
a813c111 | 2055 | x = BB_HEAD (bb); |
ca6c03ca JH |
2056 | if (GET_CODE (x) == CODE_LABEL) |
2057 | { | |
a813c111 | 2058 | if (BB_END (bb) == x) |
ca6c03ca JH |
2059 | { |
2060 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2061 | bb->index); |
ca6c03ca JH |
2062 | err = 1; |
2063 | } | |
5f0d2358 | 2064 | |
ca6c03ca JH |
2065 | x = NEXT_INSN (x); |
2066 | } | |
5f0d2358 | 2067 | |
ca6c03ca JH |
2068 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2069 | { | |
2070 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2071 | bb->index); |
ca6c03ca JH |
2072 | err = 1; |
2073 | } | |
2074 | ||
a813c111 | 2075 | if (BB_END (bb) == x) |
5f0d2358 RK |
2076 | /* Do checks for empty blocks her. e */ |
2077 | ; | |
ca6c03ca | 2078 | else |
5f0d2358 RK |
2079 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2080 | { | |
2081 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2082 | { | |
2083 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2084 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2085 | err = 1; |
2086 | } | |
2087 | ||
a813c111 | 2088 | if (x == BB_END (bb)) |
5f0d2358 | 2089 | break; |
ca6c03ca | 2090 | |
83fd323c | 2091 | if (control_flow_insn_p (x)) |
5f0d2358 | 2092 | { |
0b17ab2f | 2093 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2094 | fatal_insn ("flow control insn inside a basic block", x); |
2095 | } | |
2096 | } | |
ca6c03ca JH |
2097 | } |
2098 | ||
10e9fecc JH |
2099 | /* Clean up. */ |
2100 | free (bb_info); | |
2101 | return err; | |
2102 | } | |
5f0d2358 | 2103 | |
10e9fecc JH |
2104 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2105 | cfglayout RTL. | |
5f0d2358 | 2106 | |
10e9fecc JH |
2107 | Currently it does following checks: |
2108 | - all checks of rtl_verify_flow_info_1 | |
2109 | - check that all insns are in the basic blocks | |
2110 | (except the switch handling code, barriers and notes) | |
2111 | - check that all returns are followed by barriers | |
2112 | - check that all fallthru edge points to the adjacent blocks. */ | |
2113 | static int | |
d329e058 | 2114 | rtl_verify_flow_info (void) |
10e9fecc JH |
2115 | { |
2116 | basic_block bb; | |
2117 | int err = rtl_verify_flow_info_1 (); | |
2118 | rtx x; | |
2119 | int num_bb_notes; | |
2120 | const rtx rtx_first = get_insns (); | |
2121 | basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL; | |
ca6c03ca | 2122 | |
10e9fecc JH |
2123 | FOR_EACH_BB_REVERSE (bb) |
2124 | { | |
2125 | edge e; | |
2126 | for (e = bb->succ; e; e = e->succ_next) | |
2127 | if (e->flags & EDGE_FALLTHRU) | |
2128 | break; | |
2129 | if (!e) | |
2130 | { | |
2131 | rtx insn; | |
2132 | ||
2133 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
a813c111 | 2134 | for (insn = BB_END (bb); !insn || GET_CODE (insn) != BARRIER; |
10e9fecc JH |
2135 | insn = NEXT_INSN (insn)) |
2136 | if (!insn | |
2137 | || (GET_CODE (insn) == NOTE | |
2138 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_BASIC_BLOCK)) | |
2139 | { | |
2140 | error ("missing barrier after block %i", bb->index); | |
2141 | err = 1; | |
2142 | break; | |
2143 | } | |
2144 | } | |
2145 | else if (e->src != ENTRY_BLOCK_PTR | |
2146 | && e->dest != EXIT_BLOCK_PTR) | |
2147 | { | |
2148 | rtx insn; | |
2149 | ||
2150 | if (e->src->next_bb != e->dest) | |
2151 | { | |
2152 | error | |
2153 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2154 | e->src->index, e->dest->index); | |
2155 | err = 1; | |
2156 | } | |
2157 | else | |
a813c111 | 2158 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc JH |
2159 | insn = NEXT_INSN (insn)) |
2160 | if (GET_CODE (insn) == BARRIER | |
2161 | #ifndef CASE_DROPS_THROUGH | |
2162 | || INSN_P (insn) | |
2163 | #else | |
2164 | || (INSN_P (insn) && ! JUMP_TABLE_DATA_P (insn)) | |
2165 | #endif | |
2166 | ) | |
2167 | { | |
2168 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2169 | e->src->index, e->dest->index); | |
2170 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2171 | err = 1; | |
2172 | } | |
2173 | } | |
2174 | } | |
ca6c03ca | 2175 | |
ca6c03ca | 2176 | num_bb_notes = 0; |
e0082a72 ZD |
2177 | last_bb_seen = ENTRY_BLOCK_PTR; |
2178 | ||
5f0d2358 | 2179 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2180 | { |
2181 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2182 | { | |
bf77398c | 2183 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2184 | |
ca6c03ca | 2185 | num_bb_notes++; |
e0082a72 | 2186 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2187 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2188 | |
10e9fecc | 2189 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2190 | } |
2191 | ||
10e9fecc | 2192 | if (!curr_bb) |
ca6c03ca JH |
2193 | { |
2194 | switch (GET_CODE (x)) | |
2195 | { | |
2196 | case BARRIER: | |
2197 | case NOTE: | |
2198 | break; | |
2199 | ||
2200 | case CODE_LABEL: | |
666c27b9 | 2201 | /* An addr_vec is placed outside any basic block. */ |
ca6c03ca JH |
2202 | if (NEXT_INSN (x) |
2203 | && GET_CODE (NEXT_INSN (x)) == JUMP_INSN | |
2204 | && (GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_DIFF_VEC | |
2205 | || GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_VEC)) | |
5f0d2358 | 2206 | x = NEXT_INSN (x); |
ca6c03ca JH |
2207 | |
2208 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2209 | break; | |
2210 | ||
2211 | default: | |
1f978f5f | 2212 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2213 | } |
2214 | } | |
2215 | ||
2216 | if (INSN_P (x) | |
2217 | && GET_CODE (x) == JUMP_INSN | |
2218 | && returnjump_p (x) && ! condjump_p (x) | |
2219 | && ! (NEXT_INSN (x) && GET_CODE (NEXT_INSN (x)) == BARRIER)) | |
1f978f5f | 2220 | fatal_insn ("return not followed by barrier", x); |
a813c111 | 2221 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2222 | curr_bb = NULL; |
ca6c03ca JH |
2223 | } |
2224 | ||
0b17ab2f | 2225 | if (num_bb_notes != n_basic_blocks) |
ca6c03ca | 2226 | internal_error |
0b17ab2f RH |
2227 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
2228 | num_bb_notes, n_basic_blocks); | |
ca6c03ca | 2229 | |
10e9fecc | 2230 | return err; |
ca6c03ca JH |
2231 | } |
2232 | \f | |
eaec9b3d | 2233 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2234 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2235 | Return true if any edges are eliminated. */ | |
2236 | ||
2237 | bool | |
d329e058 | 2238 | purge_dead_edges (basic_block bb) |
ca6c03ca JH |
2239 | { |
2240 | edge e, next; | |
a813c111 | 2241 | rtx insn = BB_END (bb), note; |
ca6c03ca JH |
2242 | bool purged = false; |
2243 | ||
70da1d03 JH |
2244 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
2245 | if (GET_CODE (insn) == INSN | |
2246 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) | |
2247 | { | |
2248 | rtx eqnote; | |
2249 | ||
2250 | if (! may_trap_p (PATTERN (insn)) | |
2251 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2252 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
2253 | remove_note (insn, note); | |
2254 | } | |
2255 | ||
546c093e RH |
2256 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
2257 | for (e = bb->succ; e; e = next) | |
2258 | { | |
2259 | next = e->succ_next; | |
2260 | if (e->flags & EDGE_EH) | |
2261 | { | |
a813c111 | 2262 | if (can_throw_internal (BB_END (bb))) |
546c093e RH |
2263 | continue; |
2264 | } | |
2265 | else if (e->flags & EDGE_ABNORMAL_CALL) | |
2266 | { | |
a813c111 | 2267 | if (GET_CODE (BB_END (bb)) == CALL_INSN |
546c093e RH |
2268 | && (! (note = find_reg_note (insn, REG_EH_REGION, NULL)) |
2269 | || INTVAL (XEXP (note, 0)) >= 0)) | |
2270 | continue; | |
2271 | } | |
2272 | else | |
2273 | continue; | |
2274 | ||
2275 | remove_edge (e); | |
2276 | bb->flags |= BB_DIRTY; | |
2277 | purged = true; | |
2278 | } | |
5f0d2358 | 2279 | |
ca6c03ca JH |
2280 | if (GET_CODE (insn) == JUMP_INSN) |
2281 | { | |
2282 | rtx note; | |
2283 | edge b,f; | |
5f0d2358 | 2284 | |
ca6c03ca JH |
2285 | /* We do care only about conditional jumps and simplejumps. */ |
2286 | if (!any_condjump_p (insn) | |
2287 | && !returnjump_p (insn) | |
2288 | && !simplejump_p (insn)) | |
c51d95ec | 2289 | return purged; |
5f0d2358 | 2290 | |
5a1a3e5e JH |
2291 | /* Branch probability/prediction notes are defined only for |
2292 | condjumps. We've possibly turned condjump into simplejump. */ | |
2293 | if (simplejump_p (insn)) | |
2294 | { | |
2295 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2296 | if (note) | |
2297 | remove_note (insn, note); | |
2298 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
2299 | remove_note (insn, note); | |
2300 | } | |
2301 | ||
ca6c03ca JH |
2302 | for (e = bb->succ; e; e = next) |
2303 | { | |
2304 | next = e->succ_next; | |
2305 | ||
7fcd7218 JH |
2306 | /* Avoid abnormal flags to leak from computed jumps turned |
2307 | into simplejumps. */ | |
f87c27b4 | 2308 | |
0e1638d4 | 2309 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 2310 | |
5a566bed MM |
2311 | /* See if this edge is one we should keep. */ |
2312 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
2313 | /* A conditional jump can fall through into the next | |
2314 | block, so we should keep the edge. */ | |
ca6c03ca | 2315 | continue; |
5f0d2358 | 2316 | else if (e->dest != EXIT_BLOCK_PTR |
a813c111 | 2317 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
2318 | /* If the destination block is the target of the jump, |
2319 | keep the edge. */ | |
2320 | continue; | |
2321 | else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn)) | |
2322 | /* If the destination block is the exit block, and this | |
2323 | instruction is a return, then keep the edge. */ | |
ca6c03ca | 2324 | continue; |
5a566bed MM |
2325 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
2326 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
2327 | this instruction and rematerialize the EDGE_ABNORMAL |
2328 | flag we just cleared above. */ | |
2329 | { | |
2330 | e->flags |= EDGE_ABNORMAL; | |
2331 | continue; | |
2332 | } | |
5f0d2358 | 2333 | |
5a566bed | 2334 | /* We do not need this edge. */ |
c51d95ec | 2335 | bb->flags |= BB_DIRTY; |
ca6c03ca JH |
2336 | purged = true; |
2337 | remove_edge (e); | |
2338 | } | |
5f0d2358 | 2339 | |
ca6c03ca | 2340 | if (!bb->succ || !purged) |
c51d95ec | 2341 | return purged; |
5f0d2358 | 2342 | |
c263766c RH |
2343 | if (dump_file) |
2344 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 2345 | |
ca6c03ca JH |
2346 | if (!optimize) |
2347 | return purged; | |
2348 | ||
2349 | /* Redistribute probabilities. */ | |
2350 | if (!bb->succ->succ_next) | |
2351 | { | |
2352 | bb->succ->probability = REG_BR_PROB_BASE; | |
2353 | bb->succ->count = bb->count; | |
f87c27b4 | 2354 | } |
ca6c03ca JH |
2355 | else |
2356 | { | |
2357 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2358 | if (!note) | |
2359 | return purged; | |
5f0d2358 | 2360 | |
ca6c03ca JH |
2361 | b = BRANCH_EDGE (bb); |
2362 | f = FALLTHRU_EDGE (bb); | |
2363 | b->probability = INTVAL (XEXP (note, 0)); | |
2364 | f->probability = REG_BR_PROB_BASE - b->probability; | |
2365 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; | |
2366 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
2367 | } | |
5f0d2358 | 2368 | |
ca6c03ca JH |
2369 | return purged; |
2370 | } | |
1722c2c8 RH |
2371 | else if (GET_CODE (insn) == CALL_INSN && SIBLING_CALL_P (insn)) |
2372 | { | |
2373 | /* First, there should not be any EH or ABCALL edges resulting | |
2374 | from non-local gotos and the like. If there were, we shouldn't | |
2375 | have created the sibcall in the first place. Second, there | |
2376 | should of course never have been a fallthru edge. */ | |
2377 | if (!bb->succ || bb->succ->succ_next) | |
2378 | abort (); | |
792bb204 | 2379 | if (bb->succ->flags != (EDGE_SIBCALL | EDGE_ABNORMAL)) |
1722c2c8 RH |
2380 | abort (); |
2381 | ||
2382 | return 0; | |
2383 | } | |
ca6c03ca | 2384 | |
ca6c03ca JH |
2385 | /* If we don't see a jump insn, we don't know exactly why the block would |
2386 | have been broken at this point. Look for a simple, non-fallthru edge, | |
2387 | as these are only created by conditional branches. If we find such an | |
2388 | edge we know that there used to be a jump here and can then safely | |
2389 | remove all non-fallthru edges. */ | |
2390 | for (e = bb->succ; e && (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU)); | |
5f0d2358 RK |
2391 | e = e->succ_next) |
2392 | ; | |
2393 | ||
ca6c03ca JH |
2394 | if (!e) |
2395 | return purged; | |
5f0d2358 | 2396 | |
ca6c03ca JH |
2397 | for (e = bb->succ; e; e = next) |
2398 | { | |
2399 | next = e->succ_next; | |
2400 | if (!(e->flags & EDGE_FALLTHRU)) | |
c51d95ec JH |
2401 | { |
2402 | bb->flags |= BB_DIRTY; | |
2403 | remove_edge (e); | |
2404 | purged = true; | |
2405 | } | |
ca6c03ca | 2406 | } |
5f0d2358 | 2407 | |
ca6c03ca JH |
2408 | if (!bb->succ || bb->succ->succ_next) |
2409 | abort (); | |
5f0d2358 | 2410 | |
ca6c03ca JH |
2411 | bb->succ->probability = REG_BR_PROB_BASE; |
2412 | bb->succ->count = bb->count; | |
2413 | ||
c263766c RH |
2414 | if (dump_file) |
2415 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 2416 | bb->index); |
ca6c03ca JH |
2417 | return purged; |
2418 | } | |
2419 | ||
5f0d2358 RK |
2420 | /* Search all basic blocks for potentially dead edges and purge them. Return |
2421 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
2422 | |
2423 | bool | |
d329e058 | 2424 | purge_all_dead_edges (int update_life_p) |
ca6c03ca | 2425 | { |
e0082a72 | 2426 | int purged = false; |
710af899 | 2427 | sbitmap blocks = 0; |
e0082a72 | 2428 | basic_block bb; |
473fb060 JH |
2429 | |
2430 | if (update_life_p) | |
2431 | { | |
d55bc081 | 2432 | blocks = sbitmap_alloc (last_basic_block); |
473fb060 JH |
2433 | sbitmap_zero (blocks); |
2434 | } | |
5f0d2358 | 2435 | |
e0082a72 | 2436 | FOR_EACH_BB (bb) |
473fb060 | 2437 | { |
e0082a72 | 2438 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 2439 | |
473fb060 JH |
2440 | purged |= purged_here; |
2441 | if (purged_here && update_life_p) | |
e0082a72 | 2442 | SET_BIT (blocks, bb->index); |
473fb060 | 2443 | } |
5f0d2358 | 2444 | |
473fb060 JH |
2445 | if (update_life_p && purged) |
2446 | update_life_info (blocks, UPDATE_LIFE_GLOBAL, | |
2447 | PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE | |
2448 | | PROP_KILL_DEAD_CODE); | |
5f0d2358 | 2449 | |
473fb060 JH |
2450 | if (update_life_p) |
2451 | sbitmap_free (blocks); | |
ca6c03ca JH |
2452 | return purged; |
2453 | } | |
9ee634e3 JH |
2454 | |
2455 | /* Same as split_block but update cfg_layout structures. */ | |
f470c378 ZD |
2456 | |
2457 | static basic_block | |
d329e058 | 2458 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 JH |
2459 | { |
2460 | rtx insn = insnp; | |
f470c378 | 2461 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 2462 | |
f470c378 ZD |
2463 | new_bb->rbi->footer = bb->rbi->footer; |
2464 | bb->rbi->footer = NULL; | |
9ee634e3 | 2465 | |
f470c378 | 2466 | return new_bb; |
9ee634e3 JH |
2467 | } |
2468 | ||
2469 | ||
2470 | /* Redirect Edge to DEST. */ | |
6de9cd9a | 2471 | static edge |
d329e058 | 2472 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
2473 | { |
2474 | basic_block src = e->src; | |
6de9cd9a | 2475 | edge ret; |
9ee634e3 | 2476 | |
bc35512f | 2477 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 2478 | return NULL; |
bc35512f | 2479 | |
3348b696 | 2480 | if (e->dest == dest) |
6de9cd9a | 2481 | return e; |
bc35512f | 2482 | |
3348b696 | 2483 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a | 2484 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a JH |
2485 | { |
2486 | src->flags |= BB_DIRTY; | |
6de9cd9a | 2487 | return ret; |
f345f21a | 2488 | } |
bc35512f JH |
2489 | |
2490 | if (e->src == ENTRY_BLOCK_PTR | |
2491 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) | |
2492 | { | |
c263766c RH |
2493 | if (dump_file) |
2494 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
2495 | e->src->index, dest->index); |
2496 | ||
f345f21a | 2497 | e->src->flags |= BB_DIRTY; |
bc35512f | 2498 | redirect_edge_succ (e, dest); |
6de9cd9a | 2499 | return e; |
bc35512f JH |
2500 | } |
2501 | ||
9ee634e3 JH |
2502 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
2503 | in the case the basic block appears to be in sequence. Avoid this | |
2504 | transformation. */ | |
2505 | ||
9ee634e3 JH |
2506 | if (e->flags & EDGE_FALLTHRU) |
2507 | { | |
2508 | /* Redirect any branch edges unified with the fallthru one. */ | |
a813c111 | 2509 | if (GET_CODE (BB_END (src)) == JUMP_INSN |
432f982f JH |
2510 | && label_is_jump_target_p (BB_HEAD (e->dest), |
2511 | BB_END (src))) | |
9ee634e3 | 2512 | { |
c263766c RH |
2513 | if (dump_file) |
2514 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
2515 | "%i->%i redirected to %i\n", |
2516 | e->src->index, e->dest->index, dest->index); | |
2517 | e->flags &= ~EDGE_FALLTHRU; | |
2518 | if (!redirect_branch_edge (e, dest)) | |
9ee634e3 | 2519 | abort (); |
432f982f | 2520 | e->flags |= EDGE_FALLTHRU; |
f345f21a | 2521 | e->src->flags |= BB_DIRTY; |
6de9cd9a | 2522 | return e; |
9ee634e3 JH |
2523 | } |
2524 | /* In case we are redirecting fallthru edge to the branch edge | |
2525 | of conditional jump, remove it. */ | |
2526 | if (src->succ->succ_next | |
2527 | && !src->succ->succ_next->succ_next) | |
2528 | { | |
2529 | edge s = e->succ_next ? e->succ_next : src->succ; | |
2530 | if (s->dest == dest | |
a813c111 SB |
2531 | && any_condjump_p (BB_END (src)) |
2532 | && onlyjump_p (BB_END (src))) | |
2533 | delete_insn (BB_END (src)); | |
9ee634e3 | 2534 | } |
6de9cd9a | 2535 | ret = redirect_edge_succ_nodup (e, dest); |
c263766c RH |
2536 | if (dump_file) |
2537 | fprintf (dump_file, "Fallthru edge %i->%i redirected to %i\n", | |
bc35512f | 2538 | e->src->index, e->dest->index, dest->index); |
9ee634e3 JH |
2539 | } |
2540 | else | |
bc35512f | 2541 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
2542 | |
2543 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
a813c111 | 2544 | if (simplejump_p (BB_END (src))) |
bc35512f | 2545 | abort (); |
9ee634e3 | 2546 | |
f345f21a | 2547 | src->flags |= BB_DIRTY; |
9ee634e3 JH |
2548 | return ret; |
2549 | } | |
2550 | ||
2551 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
2552 | static basic_block | |
d329e058 | 2553 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 JH |
2554 | { |
2555 | if (!cfg_layout_redirect_edge_and_branch (e, dest)) | |
2556 | abort (); | |
2557 | return NULL; | |
2558 | } | |
2559 | ||
f470c378 ZD |
2560 | /* Same as delete_basic_block but update cfg_layout structures. */ |
2561 | ||
9ee634e3 | 2562 | static void |
d329e058 | 2563 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 2564 | { |
a813c111 | 2565 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 2566 | |
bc35512f | 2567 | if (bb->rbi->header) |
9ee634e3 | 2568 | { |
a813c111 | 2569 | next = BB_HEAD (bb); |
9ee634e3 | 2570 | if (prev) |
bc35512f | 2571 | NEXT_INSN (prev) = bb->rbi->header; |
9ee634e3 | 2572 | else |
bc35512f JH |
2573 | set_first_insn (bb->rbi->header); |
2574 | PREV_INSN (bb->rbi->header) = prev; | |
2575 | insn = bb->rbi->header; | |
9ee634e3 JH |
2576 | while (NEXT_INSN (insn)) |
2577 | insn = NEXT_INSN (insn); | |
2578 | NEXT_INSN (insn) = next; | |
2579 | PREV_INSN (next) = insn; | |
2580 | } | |
a813c111 | 2581 | next = NEXT_INSN (BB_END (bb)); |
bc35512f | 2582 | if (bb->rbi->footer) |
9ee634e3 | 2583 | { |
bc35512f JH |
2584 | insn = bb->rbi->footer; |
2585 | while (insn) | |
2586 | { | |
2587 | if (GET_CODE (insn) == BARRIER) | |
2588 | { | |
2589 | if (PREV_INSN (insn)) | |
2590 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
2591 | else | |
2592 | bb->rbi->footer = NEXT_INSN (insn); | |
2593 | if (NEXT_INSN (insn)) | |
2594 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
2595 | } | |
2596 | if (GET_CODE (insn) == CODE_LABEL) | |
2597 | break; | |
2598 | insn = NEXT_INSN (insn); | |
2599 | } | |
2600 | if (bb->rbi->footer) | |
2601 | { | |
a813c111 | 2602 | insn = BB_END (bb); |
bc35512f JH |
2603 | NEXT_INSN (insn) = bb->rbi->footer; |
2604 | PREV_INSN (bb->rbi->footer) = insn; | |
2605 | while (NEXT_INSN (insn)) | |
2606 | insn = NEXT_INSN (insn); | |
2607 | NEXT_INSN (insn) = next; | |
2608 | if (next) | |
2609 | PREV_INSN (next) = insn; | |
2610 | else | |
2611 | set_last_insn (insn); | |
2612 | } | |
9ee634e3 JH |
2613 | } |
2614 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
bc35512f | 2615 | to = &bb->next_bb->rbi->header; |
9ee634e3 JH |
2616 | else |
2617 | to = &cfg_layout_function_footer; | |
2618 | rtl_delete_block (bb); | |
2619 | ||
2620 | if (prev) | |
2621 | prev = NEXT_INSN (prev); | |
d329e058 | 2622 | else |
9ee634e3 JH |
2623 | prev = get_insns (); |
2624 | if (next) | |
2625 | next = PREV_INSN (next); | |
d329e058 | 2626 | else |
9ee634e3 JH |
2627 | next = get_last_insn (); |
2628 | ||
2629 | if (next && NEXT_INSN (next) != prev) | |
2630 | { | |
2631 | remaints = unlink_insn_chain (prev, next); | |
2632 | insn = remaints; | |
2633 | while (NEXT_INSN (insn)) | |
2634 | insn = NEXT_INSN (insn); | |
2635 | NEXT_INSN (insn) = *to; | |
2636 | if (*to) | |
2637 | PREV_INSN (*to) = insn; | |
2638 | *to = remaints; | |
2639 | } | |
2640 | } | |
2641 | ||
beb235f8 | 2642 | /* Return true when blocks A and B can be safely merged. */ |
bc35512f JH |
2643 | static bool |
2644 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) | |
2645 | { | |
750054a2 CT |
2646 | bool partitions_ok = true; |
2647 | ||
2648 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
2649 | mess up unconditional or indirect jumps that cross between hot | |
2650 | and cold sections. */ | |
2651 | ||
2652 | if (flag_reorder_blocks_and_partition | |
2653 | && (find_reg_note (BB_END (a), REG_CROSSING_JUMP, NULL_RTX) | |
2654 | || find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX) | |
2655 | || a->partition != b->partition)) | |
2656 | partitions_ok = false; | |
2657 | ||
bc35512f JH |
2658 | /* There must be exactly one edge in between the blocks. */ |
2659 | return (a->succ && !a->succ->succ_next && a->succ->dest == b | |
2660 | && !b->pred->pred_next && a != b | |
2661 | /* Must be simple edge. */ | |
2662 | && !(a->succ->flags & EDGE_COMPLEX) | |
750054a2 | 2663 | && partitions_ok |
bc35512f JH |
2664 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR |
2665 | /* If the jump insn has side effects, | |
2666 | we can't kill the edge. */ | |
a813c111 | 2667 | && (GET_CODE (BB_END (a)) != JUMP_INSN |
e24e7211 | 2668 | || (reload_completed |
a813c111 | 2669 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
2670 | } |
2671 | ||
2672 | /* Merge block A and B, abort when it is not possible. */ | |
2673 | static void | |
2674 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
2675 | { | |
2676 | #ifdef ENABLE_CHECKING | |
2677 | if (!cfg_layout_can_merge_blocks_p (a, b)) | |
2678 | abort (); | |
2679 | #endif | |
2680 | ||
2681 | /* If there was a CODE_LABEL beginning B, delete it. */ | |
a813c111 SB |
2682 | if (GET_CODE (BB_HEAD (b)) == CODE_LABEL) |
2683 | delete_insn (BB_HEAD (b)); | |
bc35512f JH |
2684 | |
2685 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
2686 | it cleaned up. */ | |
a813c111 | 2687 | if (GET_CODE (BB_END (a)) == JUMP_INSN) |
3348b696 | 2688 | try_redirect_by_replacing_jump (a->succ, b, true); |
a813c111 | 2689 | if (GET_CODE (BB_END (a)) == JUMP_INSN) |
bc35512f JH |
2690 | abort (); |
2691 | ||
2692 | /* Possible line number notes should appear in between. */ | |
2693 | if (b->rbi->header) | |
2694 | { | |
a813c111 | 2695 | rtx first = BB_END (a), last; |
bc35512f | 2696 | |
a813c111 | 2697 | last = emit_insn_after (b->rbi->header, BB_END (a)); |
bc35512f JH |
2698 | delete_insn_chain (NEXT_INSN (first), last); |
2699 | b->rbi->header = NULL; | |
2700 | } | |
2701 | ||
2702 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 2703 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 2704 | { |
a813c111 | 2705 | rtx first = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
bc35512f | 2706 | |
a813c111 | 2707 | emit_insn_after (first, BB_END (a)); |
bc35512f JH |
2708 | /* Skip possible DELETED_LABEL insn. */ |
2709 | if (!NOTE_INSN_BASIC_BLOCK_P (first)) | |
2710 | first = NEXT_INSN (first); | |
2711 | if (!NOTE_INSN_BASIC_BLOCK_P (first)) | |
2712 | abort (); | |
a813c111 | 2713 | BB_HEAD (b) = NULL; |
bc35512f JH |
2714 | delete_insn (first); |
2715 | } | |
2716 | /* Otherwise just re-associate the instructions. */ | |
2717 | else | |
2718 | { | |
2719 | rtx insn; | |
2720 | ||
a813c111 SB |
2721 | for (insn = BB_HEAD (b); |
2722 | insn != NEXT_INSN (BB_END (b)); | |
2723 | insn = NEXT_INSN (insn)) | |
bc35512f | 2724 | set_block_for_insn (insn, a); |
a813c111 | 2725 | insn = BB_HEAD (b); |
bc35512f JH |
2726 | /* Skip possible DELETED_LABEL insn. */ |
2727 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
2728 | insn = NEXT_INSN (insn); | |
2729 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
2730 | abort (); | |
a813c111 SB |
2731 | BB_HEAD (b) = NULL; |
2732 | BB_END (a) = BB_END (b); | |
bc35512f JH |
2733 | delete_insn (insn); |
2734 | } | |
2735 | ||
2736 | /* Possible tablejumps and barriers should appear after the block. */ | |
2737 | if (b->rbi->footer) | |
2738 | { | |
2739 | if (!a->rbi->footer) | |
2740 | a->rbi->footer = b->rbi->footer; | |
2741 | else | |
2742 | { | |
2743 | rtx last = a->rbi->footer; | |
2744 | ||
2745 | while (NEXT_INSN (last)) | |
2746 | last = NEXT_INSN (last); | |
2747 | NEXT_INSN (last) = b->rbi->footer; | |
2748 | PREV_INSN (b->rbi->footer) = last; | |
2749 | } | |
2750 | b->rbi->footer = NULL; | |
2751 | } | |
2752 | ||
c263766c RH |
2753 | if (dump_file) |
2754 | fprintf (dump_file, "Merged blocks %d and %d.\n", | |
bc35512f | 2755 | a->index, b->index); |
bc35512f JH |
2756 | } |
2757 | ||
2758 | /* Split edge E. */ | |
f470c378 | 2759 | |
bc35512f JH |
2760 | static basic_block |
2761 | cfg_layout_split_edge (edge e) | |
2762 | { | |
2763 | edge new_e; | |
2764 | basic_block new_bb = | |
2765 | create_basic_block (e->src != ENTRY_BLOCK_PTR | |
a813c111 | 2766 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
2767 | NULL_RTX, e->src); |
2768 | ||
bc35512f | 2769 | new_e = make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
2770 | redirect_edge_and_branch_force (e, new_bb); |
2771 | ||
2772 | return new_bb; | |
2773 | } | |
2774 | ||
f470c378 ZD |
2775 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
2776 | ||
2777 | static void | |
2778 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
2779 | { | |
2780 | } | |
2781 | ||
6de9cd9a DN |
2782 | /* Return 1 if BB ends with a call, possibly followed by some |
2783 | instructions that must stay with the call, 0 otherwise. */ | |
2784 | ||
2785 | static bool | |
2786 | rtl_block_ends_with_call_p (basic_block bb) | |
2787 | { | |
2788 | rtx insn = BB_END (bb); | |
2789 | ||
2790 | while (GET_CODE (insn) != CALL_INSN | |
2791 | && insn != BB_HEAD (bb) | |
2792 | && keep_with_call_p (insn)) | |
2793 | insn = PREV_INSN (insn); | |
2794 | return (GET_CODE (insn) == CALL_INSN); | |
2795 | } | |
2796 | ||
2797 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
2798 | ||
2799 | static bool | |
2800 | rtl_block_ends_with_condjump_p (basic_block bb) | |
2801 | { | |
2802 | return any_condjump_p (BB_END (bb)); | |
2803 | } | |
2804 | ||
2805 | /* Return true if we need to add fake edge to exit. | |
2806 | Helper function for rtl_flow_call_edges_add. */ | |
2807 | ||
2808 | static bool | |
2809 | need_fake_edge_p (rtx insn) | |
2810 | { | |
2811 | if (!INSN_P (insn)) | |
2812 | return false; | |
2813 | ||
2814 | if ((GET_CODE (insn) == CALL_INSN | |
2815 | && !SIBLING_CALL_P (insn) | |
2816 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
2817 | && !find_reg_note (insn, REG_ALWAYS_RETURN, NULL) | |
2818 | && !CONST_OR_PURE_CALL_P (insn))) | |
2819 | return true; | |
2820 | ||
2821 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
2822 | && MEM_VOLATILE_P (PATTERN (insn))) | |
2823 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
2824 | && asm_noperands (insn) != -1 | |
2825 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
2826 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
2827 | } | |
2828 | ||
2829 | /* Add fake edges to the function exit for any non constant and non noreturn | |
2830 | calls, volatile inline assembly in the bitmap of blocks specified by | |
2831 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
2832 | that were split. | |
2833 | ||
2834 | The goal is to expose cases in which entering a basic block does not imply | |
2835 | that all subsequent instructions must be executed. */ | |
2836 | ||
2837 | static int | |
2838 | rtl_flow_call_edges_add (sbitmap blocks) | |
2839 | { | |
2840 | int i; | |
2841 | int blocks_split = 0; | |
2842 | int last_bb = last_basic_block; | |
2843 | bool check_last_block = false; | |
2844 | ||
2845 | if (n_basic_blocks == 0) | |
2846 | return 0; | |
2847 | ||
2848 | if (! blocks) | |
2849 | check_last_block = true; | |
2850 | else | |
2851 | check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index); | |
2852 | ||
2853 | /* In the last basic block, before epilogue generation, there will be | |
2854 | a fallthru edge to EXIT. Special care is required if the last insn | |
2855 | of the last basic block is a call because make_edge folds duplicate | |
2856 | edges, which would result in the fallthru edge also being marked | |
2857 | fake, which would result in the fallthru edge being removed by | |
2858 | remove_fake_edges, which would result in an invalid CFG. | |
2859 | ||
2860 | Moreover, we can't elide the outgoing fake edge, since the block | |
2861 | profiler needs to take this into account in order to solve the minimal | |
2862 | spanning tree in the case that the call doesn't return. | |
2863 | ||
2864 | Handle this by adding a dummy instruction in a new last basic block. */ | |
2865 | if (check_last_block) | |
2866 | { | |
2867 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
2868 | rtx insn = BB_END (bb); | |
2869 | ||
2870 | /* Back up past insns that must be kept in the same block as a call. */ | |
2871 | while (insn != BB_HEAD (bb) | |
2872 | && keep_with_call_p (insn)) | |
2873 | insn = PREV_INSN (insn); | |
2874 | ||
2875 | if (need_fake_edge_p (insn)) | |
2876 | { | |
2877 | edge e; | |
2878 | ||
2879 | for (e = bb->succ; e; e = e->succ_next) | |
2880 | if (e->dest == EXIT_BLOCK_PTR) | |
2881 | { | |
2882 | insert_insn_on_edge (gen_rtx_USE (VOIDmode, const0_rtx), e); | |
2883 | commit_edge_insertions (); | |
2884 | break; | |
2885 | } | |
2886 | } | |
2887 | } | |
2888 | ||
2889 | /* Now add fake edges to the function exit for any non constant | |
2890 | calls since there is no way that we can determine if they will | |
2891 | return or not... */ | |
2892 | ||
2893 | for (i = 0; i < last_bb; i++) | |
2894 | { | |
2895 | basic_block bb = BASIC_BLOCK (i); | |
2896 | rtx insn; | |
2897 | rtx prev_insn; | |
2898 | ||
2899 | if (!bb) | |
2900 | continue; | |
2901 | ||
2902 | if (blocks && !TEST_BIT (blocks, i)) | |
2903 | continue; | |
2904 | ||
2905 | for (insn = BB_END (bb); ; insn = prev_insn) | |
2906 | { | |
2907 | prev_insn = PREV_INSN (insn); | |
2908 | if (need_fake_edge_p (insn)) | |
2909 | { | |
2910 | edge e; | |
2911 | rtx split_at_insn = insn; | |
2912 | ||
2913 | /* Don't split the block between a call and an insn that should | |
2914 | remain in the same block as the call. */ | |
2915 | if (GET_CODE (insn) == CALL_INSN) | |
2916 | while (split_at_insn != BB_END (bb) | |
2917 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
2918 | split_at_insn = NEXT_INSN (split_at_insn); | |
2919 | ||
2920 | /* The handling above of the final block before the epilogue | |
2921 | should be enough to verify that there is no edge to the exit | |
2922 | block in CFG already. Calling make_edge in such case would | |
2923 | cause us to mark that edge as fake and remove it later. */ | |
2924 | ||
2925 | #ifdef ENABLE_CHECKING | |
2926 | if (split_at_insn == BB_END (bb)) | |
2927 | for (e = bb->succ; e; e = e->succ_next) | |
2928 | if (e->dest == EXIT_BLOCK_PTR) | |
2929 | abort (); | |
2930 | #endif | |
2931 | ||
2932 | /* Note that the following may create a new basic block | |
2933 | and renumber the existing basic blocks. */ | |
2934 | if (split_at_insn != BB_END (bb)) | |
2935 | { | |
2936 | e = split_block (bb, split_at_insn); | |
2937 | if (e) | |
2938 | blocks_split++; | |
2939 | } | |
2940 | ||
2941 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
2942 | } | |
2943 | ||
2944 | if (insn == BB_HEAD (bb)) | |
2945 | break; | |
2946 | } | |
2947 | } | |
2948 | ||
2949 | if (blocks_split) | |
2950 | verify_flow_info (); | |
2951 | ||
2952 | return blocks_split; | |
2953 | } | |
2954 | ||
9ee634e3 JH |
2955 | /* Implementation of CFG manipulation for linearized RTL. */ |
2956 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 2957 | "rtl", |
9ee634e3 | 2958 | rtl_verify_flow_info, |
10e9fecc | 2959 | rtl_dump_bb, |
bc35512f | 2960 | rtl_create_basic_block, |
9ee634e3 JH |
2961 | rtl_redirect_edge_and_branch, |
2962 | rtl_redirect_edge_and_branch_force, | |
2963 | rtl_delete_block, | |
2964 | rtl_split_block, | |
f470c378 | 2965 | rtl_move_block_after, |
bc35512f JH |
2966 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
2967 | rtl_merge_blocks, | |
6de9cd9a DN |
2968 | rtl_predict_edge, |
2969 | rtl_predicted_by_p, | |
2970 | NULL, /* can_duplicate_block_p */ | |
2971 | NULL, /* duplicate_block */ | |
f470c378 ZD |
2972 | rtl_split_edge, |
2973 | rtl_make_forwarder_block, | |
6de9cd9a DN |
2974 | rtl_tidy_fallthru_edge, |
2975 | rtl_block_ends_with_call_p, | |
2976 | rtl_block_ends_with_condjump_p, | |
2977 | rtl_flow_call_edges_add | |
9ee634e3 JH |
2978 | }; |
2979 | ||
2980 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
2981 | basic block connected via fallthru edges does not have to be adjacent. | |
2982 | This representation will hopefully become the default one in future | |
2983 | version of the compiler. */ | |
6de9cd9a DN |
2984 | |
2985 | /* We do not want to declare these functions in a header file, since they | |
2986 | should only be used through the cfghooks interface, and we do not want to | |
2987 | move them here since it would require also moving quite a lot of related | |
2988 | code. */ | |
2989 | extern bool cfg_layout_can_duplicate_bb_p (basic_block); | |
2990 | extern basic_block cfg_layout_duplicate_bb (basic_block); | |
2991 | ||
9ee634e3 | 2992 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 2993 | "cfglayout mode", |
bc35512f | 2994 | rtl_verify_flow_info_1, |
10e9fecc | 2995 | rtl_dump_bb, |
bc35512f | 2996 | cfg_layout_create_basic_block, |
9ee634e3 JH |
2997 | cfg_layout_redirect_edge_and_branch, |
2998 | cfg_layout_redirect_edge_and_branch_force, | |
2999 | cfg_layout_delete_block, | |
3000 | cfg_layout_split_block, | |
f470c378 | 3001 | rtl_move_block_after, |
bc35512f JH |
3002 | cfg_layout_can_merge_blocks_p, |
3003 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
3004 | rtl_predict_edge, |
3005 | rtl_predicted_by_p, | |
3006 | cfg_layout_can_duplicate_bb_p, | |
3007 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
3008 | cfg_layout_split_edge, |
3009 | rtl_make_forwarder_block, | |
6de9cd9a DN |
3010 | NULL, |
3011 | rtl_block_ends_with_call_p, | |
3012 | rtl_block_ends_with_condjump_p, | |
3013 | rtl_flow_call_edges_add | |
9ee634e3 | 3014 | }; |
6de9cd9a | 3015 |