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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, | |
a3e6a37b JJ |
3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, |
4 | 2011, 2012 Free Software Foundation, Inc. | |
ca6c03ca JH |
5 | |
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 10 | Software Foundation; either version 3, or (at your option) any later |
ca6c03ca JH |
11 | version. |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ | |
ca6c03ca | 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 | |
ba5e9aca EB |
33 | - CFG fixing after coarse manipulation |
34 | fixup_abnormal_edges | |
bc35512f JH |
35 | |
36 | Functions not supposed for generic use: | |
5f0d2358 | 37 | - Infrastructure to determine quickly basic block for insn |
ca6c03ca | 38 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5f0d2358 | 39 | - Edge redirection with updating and optimizing of insn chain |
bc35512f | 40 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
ca6c03ca JH |
41 | \f |
42 | #include "config.h" | |
43 | #include "system.h" | |
4977bab6 ZW |
44 | #include "coretypes.h" |
45 | #include "tm.h" | |
ca6c03ca | 46 | #include "tree.h" |
ca6c03ca JH |
47 | #include "hard-reg-set.h" |
48 | #include "basic-block.h" | |
49 | #include "regs.h" | |
50 | #include "flags.h" | |
ca6c03ca JH |
51 | #include "function.h" |
52 | #include "except.h" | |
0cbd9993 | 53 | #include "rtl-error.h" |
ca6c03ca JH |
54 | #include "tm_p.h" |
55 | #include "obstack.h" | |
2a34bece | 56 | #include "insn-attr.h" |
0a2ed1f1 | 57 | #include "insn-config.h" |
ff25ef99 | 58 | #include "expr.h" |
9fb32434 | 59 | #include "target.h" |
677f3fa8 | 60 | #include "common/common-target.h" |
1cb7dfc3 | 61 | #include "cfgloop.h" |
5e2d947c | 62 | #include "ggc.h" |
ef330312 | 63 | #include "tree-pass.h" |
6fb5fa3c | 64 | #include "df.h" |
ca6c03ca | 65 | |
78bde837 SB |
66 | /* Holds the interesting leading and trailing notes for the function. |
67 | Only applicable if the CFG is in cfglayout mode. */ | |
68 | static GTY(()) rtx cfg_layout_function_footer; | |
69 | static GTY(()) rtx cfg_layout_function_header; | |
70 | ||
71 | static rtx skip_insns_after_block (basic_block); | |
72 | static void record_effective_endpoints (void); | |
73 | static rtx label_for_bb (basic_block); | |
74 | static void fixup_reorder_chain (void); | |
75 | ||
76 | void verify_insn_chain (void); | |
77 | static void fixup_fallthru_exit_predecessor (void); | |
9678086d KG |
78 | static int can_delete_note_p (const_rtx); |
79 | static int can_delete_label_p (const_rtx); | |
d329e058 | 80 | static basic_block rtl_split_edge (edge); |
f470c378 | 81 | static bool rtl_move_block_after (basic_block, basic_block); |
d329e058 | 82 | static int rtl_verify_flow_info (void); |
f470c378 | 83 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 84 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
85 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
86 | static void cfg_layout_delete_block (basic_block); | |
87 | static void rtl_delete_block (basic_block); | |
88 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
6de9cd9a | 89 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 | 90 | static basic_block rtl_split_block (basic_block, void *); |
a315c44c | 91 | static void rtl_dump_bb (FILE *, basic_block, int, int); |
d329e058 | 92 | static int rtl_verify_flow_info_1 (void); |
f470c378 | 93 | static void rtl_make_forwarder_block (edge); |
ca6c03ca JH |
94 | \f |
95 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 96 | so that we may simply delete it. */ |
ca6c03ca JH |
97 | |
98 | static int | |
9678086d | 99 | can_delete_note_p (const_rtx note) |
ca6c03ca | 100 | { |
cd9c1ca8 RH |
101 | switch (NOTE_KIND (note)) |
102 | { | |
103 | case NOTE_INSN_DELETED: | |
104 | case NOTE_INSN_BASIC_BLOCK: | |
105 | case NOTE_INSN_EPILOGUE_BEG: | |
106 | return true; | |
107 | ||
108 | default: | |
109 | return false; | |
110 | } | |
ca6c03ca JH |
111 | } |
112 | ||
113 | /* True if a given label can be deleted. */ | |
114 | ||
115 | static int | |
9678086d | 116 | can_delete_label_p (const_rtx label) |
ca6c03ca | 117 | { |
5f0d2358 RK |
118 | return (!LABEL_PRESERVE_P (label) |
119 | /* User declared labels must be preserved. */ | |
120 | && LABEL_NAME (label) == 0 | |
610d2478 | 121 | && !in_expr_list_p (forced_labels, label)); |
ca6c03ca JH |
122 | } |
123 | ||
03fbe718 | 124 | /* Delete INSN by patching it out. */ |
ca6c03ca | 125 | |
03fbe718 | 126 | void |
d329e058 | 127 | delete_insn (rtx insn) |
ca6c03ca | 128 | { |
ca6c03ca JH |
129 | rtx note; |
130 | bool really_delete = true; | |
131 | ||
4b4bf941 | 132 | if (LABEL_P (insn)) |
ca6c03ca JH |
133 | { |
134 | /* Some labels can't be directly removed from the INSN chain, as they | |
c22cacf3 MS |
135 | might be references via variables, constant pool etc. |
136 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
ca6c03ca JH |
137 | if (! can_delete_label_p (insn)) |
138 | { | |
139 | const char *name = LABEL_NAME (insn); | |
03fbe718 TV |
140 | basic_block bb = BLOCK_FOR_INSN (insn); |
141 | rtx bb_note = NEXT_INSN (insn); | |
ca6c03ca JH |
142 | |
143 | really_delete = false; | |
144 | PUT_CODE (insn, NOTE); | |
a38e7aa5 | 145 | NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL; |
6773e15f | 146 | NOTE_DELETED_LABEL_NAME (insn) = name; |
03fbe718 TV |
147 | |
148 | if (bb_note != NULL_RTX && NOTE_INSN_BASIC_BLOCK_P (bb_note) | |
149 | && BLOCK_FOR_INSN (bb_note) == bb) | |
150 | { | |
151 | reorder_insns_nobb (insn, insn, bb_note); | |
152 | BB_HEAD (bb) = bb_note; | |
153 | if (BB_END (bb) == bb_note) | |
154 | BB_END (bb) = insn; | |
155 | } | |
ca6c03ca | 156 | } |
5f0d2358 | 157 | |
ca6c03ca JH |
158 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
159 | } | |
160 | ||
161 | if (really_delete) | |
162 | { | |
cda94cbb | 163 | /* If this insn has already been deleted, something is very wrong. */ |
341c100f | 164 | gcc_assert (!INSN_DELETED_P (insn)); |
ca6c03ca JH |
165 | remove_insn (insn); |
166 | INSN_DELETED_P (insn) = 1; | |
167 | } | |
168 | ||
169 | /* If deleting a jump, decrement the use count of the label. Deleting | |
170 | the label itself should happen in the normal course of block merging. */ | |
cf7c4aa6 | 171 | if (JUMP_P (insn)) |
9295a326 | 172 | { |
cf7c4aa6 HPN |
173 | if (JUMP_LABEL (insn) |
174 | && LABEL_P (JUMP_LABEL (insn))) | |
175 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
176 | ||
177 | /* If there are more targets, remove them too. */ | |
178 | while ((note | |
179 | = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX | |
4b4bf941 | 180 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
181 | { |
182 | LABEL_NUSES (XEXP (note, 0))--; | |
183 | remove_note (insn, note); | |
184 | } | |
185 | } | |
ca6c03ca | 186 | |
cf7c4aa6 HPN |
187 | /* Also if deleting any insn that references a label as an operand. */ |
188 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX | |
189 | && LABEL_P (XEXP (note, 0))) | |
190 | { | |
191 | LABEL_NUSES (XEXP (note, 0))--; | |
192 | remove_note (insn, note); | |
193 | } | |
194 | ||
481683e1 | 195 | if (JUMP_TABLE_DATA_P (insn)) |
ca6c03ca JH |
196 | { |
197 | rtx pat = PATTERN (insn); | |
198 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
199 | int len = XVECLEN (pat, diff_vec_p); | |
200 | int i; | |
201 | ||
202 | for (i = 0; i < len; i++) | |
a124fcda RH |
203 | { |
204 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
205 | ||
206 | /* When deleting code in bulk (e.g. removing many unreachable | |
207 | blocks) we can delete a label that's a target of the vector | |
208 | before deleting the vector itself. */ | |
4b4bf941 | 209 | if (!NOTE_P (label)) |
a124fcda RH |
210 | LABEL_NUSES (label)--; |
211 | } | |
ca6c03ca | 212 | } |
ca6c03ca JH |
213 | } |
214 | ||
3dec4024 | 215 | /* Like delete_insn but also purge dead edges from BB. */ |
9ed7b221 | 216 | |
03fbe718 | 217 | void |
d329e058 | 218 | delete_insn_and_edges (rtx insn) |
3dec4024 | 219 | { |
3dec4024 JH |
220 | bool purge = false; |
221 | ||
ba4f7968 | 222 | if (INSN_P (insn) |
3dec4024 | 223 | && BLOCK_FOR_INSN (insn) |
a813c111 | 224 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 | 225 | purge = true; |
03fbe718 | 226 | delete_insn (insn); |
3dec4024 JH |
227 | if (purge) |
228 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
3dec4024 JH |
229 | } |
230 | ||
ca6c03ca | 231 | /* Unlink a chain of insns between START and FINISH, leaving notes |
a7b87f73 ZD |
232 | that must be paired. If CLEAR_BB is true, we set bb field for |
233 | insns that cannot be removed to NULL. */ | |
ca6c03ca JH |
234 | |
235 | void | |
a7b87f73 | 236 | delete_insn_chain (rtx start, rtx finish, bool clear_bb) |
ca6c03ca | 237 | { |
03fbe718 | 238 | rtx prev, current; |
ca6c03ca | 239 | |
5f0d2358 RK |
240 | /* Unchain the insns one by one. It would be quicker to delete all of these |
241 | with a single unchaining, rather than one at a time, but we need to keep | |
242 | the NOTE's. */ | |
03fbe718 | 243 | current = finish; |
ca6c03ca JH |
244 | while (1) |
245 | { | |
03fbe718 TV |
246 | prev = PREV_INSN (current); |
247 | if (NOTE_P (current) && !can_delete_note_p (current)) | |
ca6c03ca JH |
248 | ; |
249 | else | |
03fbe718 | 250 | delete_insn (current); |
ca6c03ca | 251 | |
03fbe718 TV |
252 | if (clear_bb && !INSN_DELETED_P (current)) |
253 | set_block_for_insn (current, NULL); | |
a7b87f73 | 254 | |
03fbe718 | 255 | if (current == start) |
ca6c03ca | 256 | break; |
03fbe718 | 257 | current = prev; |
ca6c03ca JH |
258 | } |
259 | } | |
260 | \f | |
5f0d2358 RK |
261 | /* Create a new basic block consisting of the instructions between HEAD and END |
262 | inclusive. This function is designed to allow fast BB construction - reuses | |
263 | the note and basic block struct in BB_NOTE, if any and do not grow | |
264 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
265 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
266 | and HEAD can be NULL to create basic block at the end of INSN chain. |
267 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
268 | |
269 | basic_block | |
d329e058 | 270 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
271 | { |
272 | basic_block bb; | |
273 | ||
274 | if (bb_note | |
ca6c03ca JH |
275 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
276 | && bb->aux == NULL) | |
277 | { | |
278 | /* If we found an existing note, thread it back onto the chain. */ | |
279 | ||
280 | rtx after; | |
281 | ||
4b4bf941 | 282 | if (LABEL_P (head)) |
ca6c03ca JH |
283 | after = head; |
284 | else | |
285 | { | |
286 | after = PREV_INSN (head); | |
287 | head = bb_note; | |
288 | } | |
289 | ||
290 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 291 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
292 | } |
293 | else | |
294 | { | |
295 | /* Otherwise we must create a note and a basic block structure. */ | |
296 | ||
297 | bb = alloc_block (); | |
298 | ||
5e2d947c | 299 | init_rtl_bb_info (bb); |
ca6c03ca | 300 | if (!head && !end) |
5f0d2358 RK |
301 | head = end = bb_note |
302 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 303 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
304 | { |
305 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
306 | if (head == end) | |
307 | end = bb_note; | |
308 | } | |
309 | else | |
310 | { | |
311 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
312 | head = bb_note; | |
313 | if (!end) | |
314 | end = head; | |
315 | } | |
5f0d2358 | 316 | |
ca6c03ca JH |
317 | NOTE_BASIC_BLOCK (bb_note) = bb; |
318 | } | |
319 | ||
320 | /* Always include the bb note in the block. */ | |
321 | if (NEXT_INSN (end) == bb_note) | |
322 | end = bb_note; | |
323 | ||
a813c111 SB |
324 | BB_HEAD (bb) = head; |
325 | BB_END (bb) = end; | |
852c6ec7 | 326 | bb->index = last_basic_block++; |
5e2d947c | 327 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 328 | link_block (bb, after); |
68f9b844 | 329 | SET_BASIC_BLOCK (bb->index, bb); |
6fb5fa3c | 330 | df_bb_refs_record (bb->index, false); |
ba4f7968 | 331 | update_bb_for_insn (bb); |
076c7ab8 | 332 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
333 | |
334 | /* Tag the block so that we know it has been used when considering | |
335 | other basic block notes. */ | |
336 | bb->aux = bb; | |
337 | ||
338 | return bb; | |
339 | } | |
340 | ||
5f0d2358 | 341 | /* Create new basic block consisting of instructions in between HEAD and END |
ffe14686 AM |
342 | and place it to the BB chain after block AFTER. END can be NULL to |
343 | create a new empty basic block before HEAD. Both END and HEAD can be | |
344 | NULL to create basic block at the end of INSN chain. */ | |
ca6c03ca | 345 | |
bc35512f JH |
346 | static basic_block |
347 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 348 | { |
ae50c0cb | 349 | rtx head = (rtx) headp, end = (rtx) endp; |
ca6c03ca | 350 | basic_block bb; |
0b17ab2f | 351 | |
7eca0767 | 352 | /* Grow the basic block array if needed. */ |
68f9b844 | 353 | if ((size_t) last_basic_block >= VEC_length (basic_block, basic_block_info)) |
7eca0767 JH |
354 | { |
355 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; | |
a590ac65 | 356 | VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size); |
7eca0767 | 357 | } |
0b17ab2f | 358 | |
bf77398c | 359 | n_basic_blocks++; |
ca6c03ca | 360 | |
852c6ec7 | 361 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
362 | bb->aux = NULL; |
363 | return bb; | |
364 | } | |
bc35512f JH |
365 | |
366 | static basic_block | |
367 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
368 | { | |
369 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
370 | ||
bc35512f JH |
371 | return newbb; |
372 | } | |
ca6c03ca JH |
373 | \f |
374 | /* Delete the insns in a (non-live) block. We physically delete every | |
375 | non-deleted-note insn, and update the flow graph appropriately. | |
376 | ||
377 | Return nonzero if we deleted an exception handler. */ | |
378 | ||
379 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
380 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
381 | ||
f0fda11c | 382 | static void |
d329e058 | 383 | rtl_delete_block (basic_block b) |
ca6c03ca | 384 | { |
96370780 | 385 | rtx insn, end; |
ca6c03ca JH |
386 | |
387 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
388 | label for an exception handler which can't be reached. We need |
389 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 390 | insn = BB_HEAD (b); |
ca6c03ca | 391 | |
96370780 | 392 | end = get_last_bb_insn (b); |
ca6c03ca JH |
393 | |
394 | /* Selectively delete the entire chain. */ | |
a813c111 | 395 | BB_HEAD (b) = NULL; |
a7b87f73 ZD |
396 | delete_insn_chain (insn, end, true); |
397 | ||
6fb5fa3c DB |
398 | |
399 | if (dump_file) | |
400 | fprintf (dump_file, "deleting block %d\n", b->index); | |
401 | df_bb_delete (b->index); | |
ca6c03ca JH |
402 | } |
403 | \f | |
852c6ec7 | 404 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
405 | |
406 | void | |
d329e058 | 407 | compute_bb_for_insn (void) |
ca6c03ca | 408 | { |
e0082a72 | 409 | basic_block bb; |
ca6c03ca | 410 | |
e0082a72 | 411 | FOR_EACH_BB (bb) |
ca6c03ca | 412 | { |
a813c111 | 413 | rtx end = BB_END (bb); |
5f0d2358 | 414 | rtx insn; |
ca6c03ca | 415 | |
a813c111 | 416 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 417 | { |
ba4f7968 | 418 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
419 | if (insn == end) |
420 | break; | |
ca6c03ca JH |
421 | } |
422 | } | |
423 | } | |
424 | ||
425 | /* Release the basic_block_for_insn array. */ | |
426 | ||
c2924966 | 427 | unsigned int |
d329e058 | 428 | free_bb_for_insn (void) |
ca6c03ca | 429 | { |
ba4f7968 JH |
430 | rtx insn; |
431 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
4b4bf941 | 432 | if (!BARRIER_P (insn)) |
ba4f7968 | 433 | BLOCK_FOR_INSN (insn) = NULL; |
c2924966 | 434 | return 0; |
ca6c03ca JH |
435 | } |
436 | ||
2a34bece EB |
437 | static unsigned int |
438 | rest_of_pass_free_cfg (void) | |
439 | { | |
440 | #ifdef DELAY_SLOTS | |
441 | /* The resource.c machinery uses DF but the CFG isn't guaranteed to be | |
442 | valid at that point so it would be too late to call df_analyze. */ | |
443 | if (optimize > 0 && flag_delayed_branch) | |
ad78b8a6 EB |
444 | { |
445 | df_note_add_problem (); | |
446 | df_analyze (); | |
447 | } | |
2a34bece EB |
448 | #endif |
449 | ||
450 | free_bb_for_insn (); | |
451 | return 0; | |
452 | } | |
453 | ||
8ddbbcae | 454 | struct rtl_opt_pass pass_free_cfg = |
ef330312 | 455 | { |
8ddbbcae JH |
456 | { |
457 | RTL_PASS, | |
e0a42b0f | 458 | "*free_cfg", /* name */ |
ef330312 | 459 | NULL, /* gate */ |
2a34bece | 460 | rest_of_pass_free_cfg, /* execute */ |
ef330312 PB |
461 | NULL, /* sub */ |
462 | NULL, /* next */ | |
463 | 0, /* static_pass_number */ | |
7072a650 | 464 | TV_NONE, /* tv_id */ |
ef330312 PB |
465 | 0, /* properties_required */ |
466 | 0, /* properties_provided */ | |
467 | PROP_cfg, /* properties_destroyed */ | |
468 | 0, /* todo_flags_start */ | |
469 | 0, /* todo_flags_finish */ | |
8ddbbcae | 470 | } |
ef330312 PB |
471 | }; |
472 | ||
91278841 AP |
473 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
474 | rtx | |
475 | entry_of_function (void) | |
476 | { | |
c22cacf3 | 477 | return (n_basic_blocks > NUM_FIXED_BLOCKS ? |
24bd1a0b | 478 | BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ()); |
91278841 AP |
479 | } |
480 | ||
11b904a1 BS |
481 | /* Emit INSN at the entry point of the function, ensuring that it is only |
482 | executed once per function. */ | |
483 | void | |
484 | emit_insn_at_entry (rtx insn) | |
485 | { | |
486 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->succs); | |
487 | edge e = ei_safe_edge (ei); | |
5419bc7f | 488 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
489 | |
490 | insert_insn_on_edge (insn, e); | |
491 | commit_edge_insertions (); | |
492 | } | |
493 | ||
6c3d0e31 | 494 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
b8698a0f | 495 | (or BARRIER if found) and notify df of the bb change. |
6c3d0e31 SP |
496 | The insn chain range is inclusive |
497 | (i.e. both BEGIN and END will be updated. */ | |
ca6c03ca | 498 | |
6c3d0e31 SP |
499 | static void |
500 | update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb) | |
ca6c03ca JH |
501 | { |
502 | rtx insn; | |
503 | ||
6c3d0e31 SP |
504 | end = NEXT_INSN (end); |
505 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
63642d5a AO |
506 | if (!BARRIER_P (insn)) |
507 | df_insn_change_bb (insn, bb); | |
ca6c03ca | 508 | } |
6c3d0e31 SP |
509 | |
510 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
511 | and notify df of the change. */ | |
512 | ||
513 | void | |
514 | update_bb_for_insn (basic_block bb) | |
515 | { | |
516 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
517 | } | |
518 | ||
532aafad SB |
519 | \f |
520 | /* Like active_insn_p, except keep the return value clobber around | |
521 | even after reload. */ | |
522 | ||
523 | static bool | |
524 | flow_active_insn_p (const_rtx insn) | |
525 | { | |
526 | if (active_insn_p (insn)) | |
527 | return true; | |
528 | ||
529 | /* A clobber of the function return value exists for buggy | |
530 | programs that fail to return a value. Its effect is to | |
531 | keep the return value from being live across the entire | |
532 | function. If we allow it to be skipped, we introduce the | |
533 | possibility for register lifetime confusion. */ | |
534 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
535 | && REG_P (XEXP (PATTERN (insn), 0)) | |
536 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
537 | return true; | |
538 | ||
539 | return false; | |
540 | } | |
541 | ||
542 | /* Return true if the block has no effect and only forwards control flow to | |
543 | its single destination. */ | |
544 | /* FIXME: Make this a cfg hook. */ | |
545 | ||
546 | bool | |
547 | forwarder_block_p (const_basic_block bb) | |
548 | { | |
549 | rtx insn; | |
550 | ||
551 | if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR | |
552 | || !single_succ_p (bb)) | |
553 | return false; | |
554 | ||
555 | /* Protect loop latches, headers and preheaders. */ | |
556 | if (current_loops) | |
557 | { | |
558 | basic_block dest; | |
559 | if (bb->loop_father->header == bb) | |
560 | return false; | |
561 | dest = EDGE_SUCC (bb, 0)->dest; | |
562 | if (dest->loop_father->header == dest) | |
563 | return false; | |
564 | } | |
565 | ||
566 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) | |
567 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
568 | return false; | |
569 | ||
570 | return (!INSN_P (insn) | |
571 | || (JUMP_P (insn) && simplejump_p (insn)) | |
572 | || !flow_active_insn_p (insn)); | |
573 | } | |
574 | ||
575 | /* Return nonzero if we can reach target from src by falling through. */ | |
576 | /* FIXME: Make this a cfg hook. */ | |
577 | ||
578 | bool | |
579 | can_fallthru (basic_block src, basic_block target) | |
580 | { | |
581 | rtx insn = BB_END (src); | |
582 | rtx insn2; | |
583 | edge e; | |
584 | edge_iterator ei; | |
585 | ||
586 | if (target == EXIT_BLOCK_PTR) | |
587 | return true; | |
588 | if (src->next_bb != target) | |
589 | return 0; | |
590 | FOR_EACH_EDGE (e, ei, src->succs) | |
591 | if (e->dest == EXIT_BLOCK_PTR | |
592 | && e->flags & EDGE_FALLTHRU) | |
593 | return 0; | |
594 | ||
595 | insn2 = BB_HEAD (target); | |
596 | if (insn2 && !active_insn_p (insn2)) | |
597 | insn2 = next_active_insn (insn2); | |
598 | ||
599 | /* ??? Later we may add code to move jump tables offline. */ | |
600 | return next_active_insn (insn) == insn2; | |
601 | } | |
602 | ||
603 | /* Return nonzero if we could reach target from src by falling through, | |
604 | if the target was made adjacent. If we already have a fall-through | |
605 | edge to the exit block, we can't do that. */ | |
606 | static bool | |
607 | could_fall_through (basic_block src, basic_block target) | |
608 | { | |
609 | edge e; | |
610 | edge_iterator ei; | |
611 | ||
612 | if (target == EXIT_BLOCK_PTR) | |
613 | return true; | |
614 | FOR_EACH_EDGE (e, ei, src->succs) | |
615 | if (e->dest == EXIT_BLOCK_PTR | |
616 | && e->flags & EDGE_FALLTHRU) | |
617 | return 0; | |
618 | return true; | |
619 | } | |
ca6c03ca | 620 | \f |
ef2be249 RS |
621 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
622 | rtx | |
623 | bb_note (basic_block bb) | |
624 | { | |
625 | rtx note; | |
626 | ||
627 | note = BB_HEAD (bb); | |
628 | if (LABEL_P (note)) | |
629 | note = NEXT_INSN (note); | |
630 | ||
631 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
632 | return note; | |
633 | } | |
634 | ||
6fb5fa3c DB |
635 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
636 | note associated with the BLOCK. */ | |
637 | ||
638 | static rtx | |
639 | first_insn_after_basic_block_note (basic_block block) | |
640 | { | |
641 | rtx insn; | |
642 | ||
643 | /* Get the first instruction in the block. */ | |
644 | insn = BB_HEAD (block); | |
645 | ||
646 | if (insn == NULL_RTX) | |
647 | return NULL_RTX; | |
648 | if (LABEL_P (insn)) | |
649 | insn = NEXT_INSN (insn); | |
650 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
651 | ||
652 | return NEXT_INSN (insn); | |
653 | } | |
654 | ||
f470c378 ZD |
655 | /* Creates a new basic block just after basic block B by splitting |
656 | everything after specified instruction I. */ | |
ca6c03ca | 657 | |
f470c378 | 658 | static basic_block |
d329e058 | 659 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
660 | { |
661 | basic_block new_bb; | |
ae50c0cb | 662 | rtx insn = (rtx) insnp; |
f470c378 | 663 | edge e; |
628f6a4e | 664 | edge_iterator ei; |
ca6c03ca | 665 | |
f470c378 ZD |
666 | if (!insn) |
667 | { | |
668 | insn = first_insn_after_basic_block_note (bb); | |
669 | ||
670 | if (insn) | |
b5b8b0ac AO |
671 | { |
672 | rtx next = insn; | |
673 | ||
674 | insn = PREV_INSN (insn); | |
675 | ||
676 | /* If the block contains only debug insns, insn would have | |
677 | been NULL in a non-debug compilation, and then we'd end | |
678 | up emitting a DELETED note. For -fcompare-debug | |
679 | stability, emit the note too. */ | |
680 | if (insn != BB_END (bb) | |
681 | && DEBUG_INSN_P (next) | |
682 | && DEBUG_INSN_P (BB_END (bb))) | |
683 | { | |
684 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
685 | next = NEXT_INSN (next); | |
686 | ||
687 | if (next == BB_END (bb)) | |
688 | emit_note_after (NOTE_INSN_DELETED, next); | |
689 | } | |
690 | } | |
f470c378 ZD |
691 | else |
692 | insn = get_last_insn (); | |
693 | } | |
694 | ||
695 | /* We probably should check type of the insn so that we do not create | |
696 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
697 | bother. */ | |
698 | if (insn == BB_END (bb)) | |
699 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
700 | |
701 | /* Create the new basic block. */ | |
a813c111 | 702 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 703 | BB_COPY_PARTITION (new_bb, bb); |
a813c111 | 704 | BB_END (bb) = insn; |
ca6c03ca JH |
705 | |
706 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
707 | new_bb->succs = bb->succs; |
708 | bb->succs = NULL; | |
709 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
710 | e->src = new_bb; |
711 | ||
6fb5fa3c DB |
712 | /* The new block starts off being dirty. */ |
713 | df_set_bb_dirty (bb); | |
f470c378 | 714 | return new_bb; |
bc35512f JH |
715 | } |
716 | ||
9be94227 EB |
717 | /* Return true if the single edge between blocks A and B is the only place |
718 | in RTL which holds some unique locus. */ | |
719 | ||
720 | static bool | |
721 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
722 | { | |
5368224f | 723 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
724 | rtx insn, end; |
725 | ||
2f13f2de | 726 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
9be94227 EB |
727 | return false; |
728 | ||
729 | /* First scan block A backward. */ | |
730 | insn = BB_END (a); | |
731 | end = PREV_INSN (BB_HEAD (a)); | |
5368224f | 732 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
9be94227 EB |
733 | insn = PREV_INSN (insn); |
734 | ||
5368224f | 735 | if (insn != end && INSN_LOCATION (insn) == goto_locus) |
9be94227 EB |
736 | return false; |
737 | ||
738 | /* Then scan block B forward. */ | |
739 | insn = BB_HEAD (b); | |
740 | if (insn) | |
741 | { | |
742 | end = NEXT_INSN (BB_END (b)); | |
743 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
744 | insn = NEXT_INSN (insn); | |
745 | ||
5368224f DC |
746 | if (insn != end && INSN_HAS_LOCATION (insn) |
747 | && INSN_LOCATION (insn) == goto_locus) | |
9be94227 EB |
748 | return false; |
749 | } | |
750 | ||
751 | return true; | |
752 | } | |
753 | ||
754 | /* If the single edge between blocks A and B is the only place in RTL which | |
755 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
756 | ||
757 | static void | |
758 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
759 | { | |
760 | if (!unique_locus_on_edge_between_p (a, b)) | |
761 | return; | |
762 | ||
763 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); | |
5368224f | 764 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
765 | } |
766 | ||
ca6c03ca | 767 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 768 | are already contiguous. */ |
ca6c03ca | 769 | |
bc35512f JH |
770 | static void |
771 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 772 | { |
a813c111 | 773 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca | 774 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
b5b8b0ac | 775 | rtx b_debug_start = b_end, b_debug_end = b_end; |
50a36e42 | 776 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
ca6c03ca JH |
777 | int b_empty = 0; |
778 | ||
6fb5fa3c | 779 | if (dump_file) |
50a36e42 EB |
780 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
781 | a->index); | |
6fb5fa3c | 782 | |
b5b8b0ac AO |
783 | while (DEBUG_INSN_P (b_end)) |
784 | b_end = PREV_INSN (b_debug_start = b_end); | |
785 | ||
ca6c03ca | 786 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 787 | if (LABEL_P (b_head)) |
ca6c03ca JH |
788 | { |
789 | /* Detect basic blocks with nothing but a label. This can happen | |
790 | in particular at the end of a function. */ | |
791 | if (b_head == b_end) | |
792 | b_empty = 1; | |
5f0d2358 | 793 | |
ca6c03ca JH |
794 | del_first = del_last = b_head; |
795 | b_head = NEXT_INSN (b_head); | |
796 | } | |
797 | ||
5f0d2358 RK |
798 | /* Delete the basic block note and handle blocks containing just that |
799 | note. */ | |
ca6c03ca JH |
800 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
801 | { | |
802 | if (b_head == b_end) | |
803 | b_empty = 1; | |
804 | if (! del_last) | |
805 | del_first = b_head; | |
5f0d2358 | 806 | |
ca6c03ca JH |
807 | del_last = b_head; |
808 | b_head = NEXT_INSN (b_head); | |
809 | } | |
810 | ||
811 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 812 | if (JUMP_P (a_end)) |
ca6c03ca JH |
813 | { |
814 | rtx prev; | |
815 | ||
816 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 817 | if (!NOTE_P (prev) |
a38e7aa5 | 818 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
a813c111 | 819 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
820 | break; |
821 | ||
822 | del_first = a_end; | |
823 | ||
824 | #ifdef HAVE_cc0 | |
825 | /* If this was a conditional jump, we need to also delete | |
826 | the insn that set cc0. */ | |
827 | if (only_sets_cc0_p (prev)) | |
828 | { | |
829 | rtx tmp = prev; | |
5f0d2358 | 830 | |
ca6c03ca JH |
831 | prev = prev_nonnote_insn (prev); |
832 | if (!prev) | |
a813c111 | 833 | prev = BB_HEAD (a); |
ca6c03ca JH |
834 | del_first = tmp; |
835 | } | |
836 | #endif | |
837 | ||
838 | a_end = PREV_INSN (del_first); | |
839 | } | |
4b4bf941 | 840 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
841 | del_first = NEXT_INSN (a_end); |
842 | ||
ca6c03ca JH |
843 | /* Delete everything marked above as well as crap that might be |
844 | hanging out between the two blocks. */ | |
9be94227 EB |
845 | BB_END (a) = a_end; |
846 | BB_HEAD (b) = b_empty ? NULL_RTX : b_head; | |
a7b87f73 | 847 | delete_insn_chain (del_first, del_last, true); |
ca6c03ca | 848 | |
9be94227 EB |
849 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
850 | some unique locus, emit a nop with that locus in between. */ | |
851 | if (!optimize) | |
852 | { | |
853 | emit_nop_for_unique_locus_between (a, b); | |
854 | a_end = BB_END (a); | |
855 | } | |
856 | ||
ca6c03ca JH |
857 | /* Reassociate the insns of B with A. */ |
858 | if (!b_empty) | |
859 | { | |
b5b8b0ac | 860 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5f0d2358 | 861 | |
9be94227 EB |
862 | BB_END (a) = b_debug_end; |
863 | BB_HEAD (b) = NULL_RTX; | |
b5b8b0ac AO |
864 | } |
865 | else if (b_end != b_debug_end) | |
866 | { | |
867 | /* Move any deleted labels and other notes between the end of A | |
868 | and the debug insns that make up B after the debug insns, | |
869 | bringing the debug insns into A while keeping the notes after | |
870 | the end of A. */ | |
871 | if (NEXT_INSN (a_end) != b_debug_start) | |
872 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
873 | b_debug_end); | |
874 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
9be94227 | 875 | BB_END (a) = b_debug_end; |
ca6c03ca | 876 | } |
5f0d2358 | 877 | |
6fb5fa3c | 878 | df_bb_delete (b->index); |
50a36e42 EB |
879 | |
880 | /* If B was a forwarder block, propagate the locus on the edge. */ | |
881 | if (forwarder_p && !EDGE_SUCC (b, 0)->goto_locus) | |
882 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; | |
883 | ||
884 | if (dump_file) | |
885 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
ca6c03ca | 886 | } |
bc35512f | 887 | |
6fb5fa3c | 888 | |
bc35512f | 889 | /* Return true when block A and B can be merged. */ |
9678086d | 890 | |
b48d0358 DN |
891 | static bool |
892 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
bc35512f | 893 | { |
750054a2 CT |
894 | /* If we are partitioning hot/cold basic blocks, we don't want to |
895 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
896 | and cold sections. |
897 | ||
8e8d5162 | 898 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
899 | be optimizable (or blocks that appear to be mergeable), but which really |
900 | must be left untouched (they are required to make it safely across | |
901 | partition boundaries). See the comments at the top of | |
8e8d5162 | 902 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 903 | |
87c8b4be | 904 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 905 | return false; |
750054a2 | 906 | |
7d776ee2 RG |
907 | /* Protect the loop latches. */ |
908 | if (current_loops && b->loop_father->latch == b) | |
909 | return false; | |
910 | ||
bc35512f | 911 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
912 | return (single_succ_p (a) |
913 | && single_succ (a) == b | |
914 | && single_pred_p (b) | |
628f6a4e | 915 | && a != b |
bc35512f | 916 | /* Must be simple edge. */ |
c5cbcccf | 917 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f JH |
918 | && a->next_bb == b |
919 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR | |
920 | /* If the jump insn has side effects, | |
921 | we can't kill the edge. */ | |
4b4bf941 | 922 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 923 | || (reload_completed |
a813c111 | 924 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 925 | } |
ca6c03ca | 926 | \f |
5f0d2358 RK |
927 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
928 | exist. */ | |
ca6c03ca JH |
929 | |
930 | rtx | |
d329e058 | 931 | block_label (basic_block block) |
ca6c03ca JH |
932 | { |
933 | if (block == EXIT_BLOCK_PTR) | |
934 | return NULL_RTX; | |
5f0d2358 | 935 | |
4b4bf941 | 936 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 937 | { |
a813c111 | 938 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 939 | } |
5f0d2358 | 940 | |
a813c111 | 941 | return BB_HEAD (block); |
ca6c03ca JH |
942 | } |
943 | ||
944 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
945 | instruction by unconditional jump or removing jump completely. This can |
946 | apply only if all edges now point to the same block. The parameters and | |
947 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 948 | |
6de9cd9a | 949 | edge |
bc35512f | 950 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
951 | { |
952 | basic_block src = e->src; | |
a813c111 | 953 | rtx insn = BB_END (src), kill_from; |
e1233a7d | 954 | rtx set; |
ca6c03ca | 955 | int fallthru = 0; |
750054a2 CT |
956 | |
957 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
958 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
959 | and cold sections. |
960 | ||
961 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
962 | be optimizable (or blocks that appear to be mergeable), but which really |
963 | must be left untouched (they are required to make it safely across | |
964 | partition boundaries). See the comments at the top of | |
8e8d5162 | 965 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 966 | |
87c8b4be CT |
967 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) |
968 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
9cf84a3c | 969 | return NULL; |
750054a2 | 970 | |
6a66a8a7 KH |
971 | /* We can replace or remove a complex jump only when we have exactly |
972 | two edges. Also, if we have exactly one outgoing edge, we can | |
973 | redirect that. */ | |
974 | if (EDGE_COUNT (src->succs) >= 3 | |
975 | /* Verify that all targets will be TARGET. Specifically, the | |
976 | edge that is not E must also go to TARGET. */ | |
977 | || (EDGE_COUNT (src->succs) == 2 | |
978 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
979 | return NULL; | |
5f0d2358 | 980 | |
6a66a8a7 | 981 | if (!onlyjump_p (insn)) |
6de9cd9a | 982 | return NULL; |
3348b696 | 983 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 984 | return NULL; |
ca6c03ca JH |
985 | |
986 | /* Avoid removing branch with side effects. */ | |
987 | set = single_set (insn); | |
988 | if (!set || side_effects_p (set)) | |
6de9cd9a | 989 | return NULL; |
ca6c03ca JH |
990 | |
991 | /* In case we zap a conditional jump, we'll need to kill | |
992 | the cc0 setter too. */ | |
993 | kill_from = insn; | |
994 | #ifdef HAVE_cc0 | |
9caea4a7 RS |
995 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
996 | && only_sets_cc0_p (PREV_INSN (insn))) | |
ca6c03ca JH |
997 | kill_from = PREV_INSN (insn); |
998 | #endif | |
999 | ||
1000 | /* See if we can create the fallthru edge. */ | |
bc35512f | 1001 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 1002 | { |
c263766c RH |
1003 | if (dump_file) |
1004 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
1005 | fallthru = 1; |
1006 | ||
eaec9b3d | 1007 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
1008 | if (in_cfglayout) |
1009 | { | |
bcc708fc | 1010 | rtx insn = BB_FOOTER (src); |
bc35512f | 1011 | |
a7b87f73 | 1012 | delete_insn_chain (kill_from, BB_END (src), false); |
bc35512f JH |
1013 | |
1014 | /* Remove barriers but keep jumptables. */ | |
1015 | while (insn) | |
1016 | { | |
4b4bf941 | 1017 | if (BARRIER_P (insn)) |
bc35512f JH |
1018 | { |
1019 | if (PREV_INSN (insn)) | |
1020 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1021 | else | |
bcc708fc | 1022 | BB_FOOTER (src) = NEXT_INSN (insn); |
bc35512f JH |
1023 | if (NEXT_INSN (insn)) |
1024 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1025 | } | |
4b4bf941 | 1026 | if (LABEL_P (insn)) |
bc35512f JH |
1027 | break; |
1028 | insn = NEXT_INSN (insn); | |
1029 | } | |
1030 | } | |
1031 | else | |
a7b87f73 ZD |
1032 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)), |
1033 | false); | |
ca6c03ca | 1034 | } |
5f0d2358 | 1035 | |
ca6c03ca JH |
1036 | /* If this already is simplejump, redirect it. */ |
1037 | else if (simplejump_p (insn)) | |
1038 | { | |
1039 | if (e->dest == target) | |
6de9cd9a | 1040 | return NULL; |
c263766c RH |
1041 | if (dump_file) |
1042 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 1043 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
1044 | if (!redirect_jump (insn, block_label (target), 0)) |
1045 | { | |
341c100f NS |
1046 | gcc_assert (target == EXIT_BLOCK_PTR); |
1047 | return NULL; | |
6ee3c8e4 | 1048 | } |
ca6c03ca | 1049 | } |
5f0d2358 | 1050 | |
6ee3c8e4 JJ |
1051 | /* Cannot do anything for target exit block. */ |
1052 | else if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 1053 | return NULL; |
6ee3c8e4 | 1054 | |
ca6c03ca JH |
1055 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1056 | else | |
1057 | { | |
1058 | rtx target_label = block_label (target); | |
eb5b8ad4 | 1059 | rtx barrier, label, table; |
ca6c03ca | 1060 | |
a7102479 | 1061 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
a813c111 | 1062 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 1063 | LABEL_NUSES (target_label)++; |
c263766c RH |
1064 | if (dump_file) |
1065 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 1066 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 1067 | |
4da2eb6b | 1068 | |
ba4807a0 LB |
1069 | delete_insn_chain (kill_from, insn, false); |
1070 | ||
4da2eb6b RH |
1071 | /* Recognize a tablejump that we are converting to a |
1072 | simple jump and remove its associated CODE_LABEL | |
1073 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
ba4807a0 LB |
1074 | if (tablejump_p (insn, &label, &table)) |
1075 | delete_insn_chain (label, table, false); | |
eb5b8ad4 | 1076 | |
a813c111 | 1077 | barrier = next_nonnote_insn (BB_END (src)); |
4b4bf941 | 1078 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 1079 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
1080 | else |
1081 | { | |
a813c111 | 1082 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
1083 | { |
1084 | /* Move the jump before barrier so that the notes | |
1085 | which originally were or were created before jump table are | |
1086 | inside the basic block. */ | |
a813c111 | 1087 | rtx new_insn = BB_END (src); |
5d693491 | 1088 | |
6c3d0e31 SP |
1089 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1090 | PREV_INSN (barrier), src); | |
5d693491 JZ |
1091 | |
1092 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
1093 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
1094 | ||
1095 | NEXT_INSN (new_insn) = barrier; | |
1096 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
1097 | ||
1098 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
1099 | PREV_INSN (barrier) = new_insn; | |
1100 | } | |
1101 | } | |
ca6c03ca JH |
1102 | } |
1103 | ||
1104 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 1105 | if (!single_succ_p (src)) |
628f6a4e | 1106 | remove_edge (e); |
c5cbcccf | 1107 | gcc_assert (single_succ_p (src)); |
628f6a4e | 1108 | |
c5cbcccf | 1109 | e = single_succ_edge (src); |
ca6c03ca JH |
1110 | if (fallthru) |
1111 | e->flags = EDGE_FALLTHRU; | |
1112 | else | |
1113 | e->flags = 0; | |
5f0d2358 | 1114 | |
ca6c03ca JH |
1115 | e->probability = REG_BR_PROB_BASE; |
1116 | e->count = src->count; | |
1117 | ||
ca6c03ca JH |
1118 | if (e->dest != target) |
1119 | redirect_edge_succ (e, target); | |
6de9cd9a | 1120 | return e; |
ca6c03ca JH |
1121 | } |
1122 | ||
4e3825db MM |
1123 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1124 | instruction INSN so that it reaches block NEW. Do this | |
1125 | only when it originally reached block OLD. Return true if this | |
1126 | worked or the original target wasn't OLD, return false if redirection | |
1127 | doesn't work. */ | |
1128 | ||
1129 | static bool | |
1130 | patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb) | |
ca6c03ca JH |
1131 | { |
1132 | rtx tmp; | |
ca6c03ca | 1133 | /* Recognize a tablejump and adjust all matching cases. */ |
e1233a7d | 1134 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
1135 | { |
1136 | rtvec vec; | |
1137 | int j; | |
4e3825db | 1138 | rtx new_label = block_label (new_bb); |
ca6c03ca | 1139 | |
4e3825db MM |
1140 | if (new_bb == EXIT_BLOCK_PTR) |
1141 | return false; | |
ca6c03ca JH |
1142 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
1143 | vec = XVEC (PATTERN (tmp), 0); | |
1144 | else | |
1145 | vec = XVEC (PATTERN (tmp), 1); | |
1146 | ||
1147 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1148 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1149 | { | |
1150 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1151 | --LABEL_NUSES (old_label); | |
1152 | ++LABEL_NUSES (new_label); | |
1153 | } | |
1154 | ||
f9da5064 | 1155 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
1156 | if ((tmp = single_set (insn)) != NULL |
1157 | && SET_DEST (tmp) == pc_rtx | |
1158 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
1159 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
1160 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
1161 | { | |
4c33cb26 | 1162 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
1163 | new_label); |
1164 | --LABEL_NUSES (old_label); | |
1165 | ++LABEL_NUSES (new_label); | |
1166 | } | |
1167 | } | |
1c384bf1 RH |
1168 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1169 | { | |
1170 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
1171 | rtx new_label, note; | |
1172 | ||
1173 | if (new_bb == EXIT_BLOCK_PTR) | |
1174 | return false; | |
1175 | new_label = block_label (new_bb); | |
1176 | ||
1177 | for (i = 0; i < n; ++i) | |
1178 | { | |
1179 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1180 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1181 | if (XEXP (old_ref, 0) == old_label) | |
1182 | { | |
1183 | ASM_OPERANDS_LABEL (tmp, i) | |
1184 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1185 | --LABEL_NUSES (old_label); | |
1186 | ++LABEL_NUSES (new_label); | |
1187 | } | |
1188 | } | |
1189 | ||
1190 | if (JUMP_LABEL (insn) == old_label) | |
1191 | { | |
1192 | JUMP_LABEL (insn) = new_label; | |
1193 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1194 | if (note) | |
1195 | remove_note (insn, note); | |
1196 | } | |
1197 | else | |
1198 | { | |
1199 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1200 | if (note) | |
1201 | remove_note (insn, note); | |
1202 | if (JUMP_LABEL (insn) != new_label | |
1203 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1204 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1205 | } | |
3b5fda81 JJ |
1206 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1207 | != NULL_RTX) | |
1208 | XEXP (note, 0) = new_label; | |
1c384bf1 | 1209 | } |
ca6c03ca JH |
1210 | else |
1211 | { | |
1212 | /* ?? We may play the games with moving the named labels from | |
1213 | one basic block to the other in case only one computed_jump is | |
1214 | available. */ | |
5f0d2358 RK |
1215 | if (computed_jump_p (insn) |
1216 | /* A return instruction can't be redirected. */ | |
1217 | || returnjump_p (insn)) | |
4e3825db | 1218 | return false; |
6ee3c8e4 | 1219 | |
4e3825db | 1220 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
6ee3c8e4 | 1221 | { |
4e3825db MM |
1222 | /* If the insn doesn't go where we think, we're confused. */ |
1223 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1224 | ||
1225 | /* If the substitution doesn't succeed, die. This can happen | |
1226 | if the back end emitted unrecognizable instructions or if | |
1227 | target is exit block on some arches. */ | |
1228 | if (!redirect_jump (insn, block_label (new_bb), 0)) | |
1229 | { | |
1230 | gcc_assert (new_bb == EXIT_BLOCK_PTR); | |
1231 | return false; | |
1232 | } | |
6ee3c8e4 | 1233 | } |
ca6c03ca | 1234 | } |
4e3825db MM |
1235 | return true; |
1236 | } | |
1237 | ||
1238 | ||
1239 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1240 | NULL on failure */ | |
1241 | static edge | |
1242 | redirect_branch_edge (edge e, basic_block target) | |
1243 | { | |
1244 | rtx old_label = BB_HEAD (e->dest); | |
1245 | basic_block src = e->src; | |
1246 | rtx insn = BB_END (src); | |
1247 | ||
1248 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1249 | if (e->flags & EDGE_FALLTHRU) | |
1250 | return NULL; | |
1251 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1252 | return NULL; | |
1253 | ||
1254 | if (!currently_expanding_to_rtl) | |
1255 | { | |
1256 | if (!patch_jump_insn (insn, old_label, target)) | |
1257 | return NULL; | |
1258 | } | |
1259 | else | |
1260 | /* When expanding this BB might actually contain multiple | |
1261 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1262 | Redirect all of those that match our label. */ | |
0f346928 | 1263 | FOR_BB_INSNS (src, insn) |
4e3825db MM |
1264 | if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target)) |
1265 | return NULL; | |
ca6c03ca | 1266 | |
c263766c RH |
1267 | if (dump_file) |
1268 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 1269 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 1270 | |
ca6c03ca | 1271 | if (e->dest != target) |
6de9cd9a | 1272 | e = redirect_edge_succ_nodup (e, target); |
6fb5fa3c | 1273 | |
6de9cd9a | 1274 | return e; |
bc35512f JH |
1275 | } |
1276 | ||
1277 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on | |
1278 | expense of adding new instructions or reordering basic blocks. | |
1279 | ||
1280 | Function can be also called with edge destination equivalent to the TARGET. | |
1281 | Then it should try the simplifications and do nothing if none is possible. | |
1282 | ||
6de9cd9a DN |
1283 | Return edge representing the branch if transformation succeeded. Return NULL |
1284 | on failure. | |
1285 | We still return NULL in case E already destinated TARGET and we didn't | |
1286 | managed to simplify instruction stream. */ | |
bc35512f | 1287 | |
6de9cd9a | 1288 | static edge |
5671bf27 | 1289 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 1290 | { |
6de9cd9a | 1291 | edge ret; |
f345f21a JH |
1292 | basic_block src = e->src; |
1293 | ||
bc35512f | 1294 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 1295 | return NULL; |
bc35512f | 1296 | |
3348b696 | 1297 | if (e->dest == target) |
6de9cd9a | 1298 | return e; |
3348b696 | 1299 | |
6de9cd9a | 1300 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a | 1301 | { |
6fb5fa3c | 1302 | df_set_bb_dirty (src); |
6de9cd9a | 1303 | return ret; |
f345f21a | 1304 | } |
bc35512f | 1305 | |
6de9cd9a DN |
1306 | ret = redirect_branch_edge (e, target); |
1307 | if (!ret) | |
1308 | return NULL; | |
5f0d2358 | 1309 | |
6fb5fa3c | 1310 | df_set_bb_dirty (src); |
6de9cd9a | 1311 | return ret; |
ca6c03ca JH |
1312 | } |
1313 | ||
4fe9b91c | 1314 | /* Like force_nonfallthru below, but additionally performs redirection |
26898771 BS |
1315 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1316 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1317 | simple_return_rtx, indicating which kind of returnjump to create. | |
1318 | It should be NULL otherwise. */ | |
ca6c03ca | 1319 | |
dc0ff1c8 | 1320 | basic_block |
26898771 | 1321 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
ca6c03ca | 1322 | { |
a3716585 | 1323 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
1324 | rtx note; |
1325 | edge new_edge; | |
a3716585 | 1326 | int abnormal_edge_flags = 0; |
a3e6a37b | 1327 | bool asm_goto_edge = false; |
7241571e | 1328 | int loc; |
ca6c03ca | 1329 | |
cb9a1d9b JH |
1330 | /* In the case the last instruction is conditional jump to the next |
1331 | instruction, first redirect the jump itself and then continue | |
b20b352b | 1332 | by creating a basic block afterwards to redirect fallthru edge. */ |
cb9a1d9b | 1333 | if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR |
a813c111 | 1334 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 1335 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1336 | { |
1337 | rtx note; | |
58e6ae30 | 1338 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1339 | bool redirected; |
cb9a1d9b | 1340 | |
341c100f NS |
1341 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1342 | gcc_assert (redirected); | |
c22cacf3 | 1343 | |
a813c111 | 1344 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1345 | if (note) |
1346 | { | |
1347 | int prob = INTVAL (XEXP (note, 0)); | |
1348 | ||
1349 | b->probability = prob; | |
1350 | b->count = e->count * prob / REG_BR_PROB_BASE; | |
1351 | e->probability -= e->probability; | |
1352 | e->count -= b->count; | |
1353 | if (e->probability < 0) | |
1354 | e->probability = 0; | |
1355 | if (e->count < 0) | |
1356 | e->count = 0; | |
1357 | } | |
1358 | } | |
1359 | ||
ca6c03ca | 1360 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1361 | { |
1362 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1363 | edge. | |
1364 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1365 | one and create separate abnormal edge to original destination. |
a3716585 | 1366 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1367 | gcc_assert (e->dest == target); |
ee44c28d SB |
1368 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1369 | e->flags &= EDGE_FALLTHRU; | |
a3716585 | 1370 | } |
341c100f | 1371 | else |
24c545ff | 1372 | { |
341c100f NS |
1373 | gcc_assert (e->flags & EDGE_FALLTHRU); |
1374 | if (e->src == ENTRY_BLOCK_PTR) | |
1375 | { | |
1376 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1377 | at the start of the function which we use to add the new |
1378 | jump. */ | |
1379 | edge tmp; | |
1380 | edge_iterator ei; | |
1381 | bool found = false; | |
c22cacf3 | 1382 | |
628f6a4e | 1383 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, ENTRY_BLOCK_PTR); |
c22cacf3 | 1384 | |
341c100f NS |
1385 | /* Change the existing edge's source to be the new block, and add |
1386 | a new edge from the entry block to the new block. */ | |
1387 | e->src = bb; | |
628f6a4e BE |
1388 | for (ei = ei_start (ENTRY_BLOCK_PTR->succs); (tmp = ei_safe_edge (ei)); ) |
1389 | { | |
1390 | if (tmp == e) | |
1391 | { | |
865851d0 | 1392 | VEC_unordered_remove (edge, ENTRY_BLOCK_PTR->succs, ei.index); |
628f6a4e BE |
1393 | found = true; |
1394 | break; | |
1395 | } | |
1396 | else | |
1397 | ei_next (&ei); | |
1398 | } | |
c22cacf3 | 1399 | |
628f6a4e | 1400 | gcc_assert (found); |
c22cacf3 | 1401 | |
d4e6fecb | 1402 | VEC_safe_push (edge, gc, bb->succs, e); |
341c100f NS |
1403 | make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU); |
1404 | } | |
24c545ff BS |
1405 | } |
1406 | ||
a3e6a37b | 1407 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
891ca07d | 1408 | don't point to the target or fallthru label. */ |
a3e6a37b JJ |
1409 | if (JUMP_P (BB_END (e->src)) |
1410 | && target != EXIT_BLOCK_PTR | |
a3e6a37b JJ |
1411 | && (e->flags & EDGE_FALLTHRU) |
1412 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
ca6c03ca | 1413 | { |
a3e6a37b JJ |
1414 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
1415 | ||
1416 | for (i = 0; i < n; ++i) | |
891ca07d JJ |
1417 | { |
1418 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
1419 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1420 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) | |
a3e6a37b | 1421 | asm_goto_edge = true; |
891ca07d | 1422 | } |
a3e6a37b JJ |
1423 | } |
1424 | ||
1425 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1426 | { | |
1427 | gcov_type count = e->count; | |
1428 | int probability = e->probability; | |
ca6c03ca | 1429 | /* Create the new structures. */ |
31a78298 | 1430 | |
79019985 RH |
1431 | /* If the old block ended with a tablejump, skip its table |
1432 | by searching forward from there. Otherwise start searching | |
1433 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1434 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1435 | note = BB_END (e->src); | |
31a78298 RH |
1436 | note = NEXT_INSN (note); |
1437 | ||
31a78298 | 1438 | jump_block = create_basic_block (note, NULL, e->src); |
a3e6a37b | 1439 | jump_block->count = count; |
ca6c03ca | 1440 | jump_block->frequency = EDGE_FREQUENCY (e); |
ca6c03ca | 1441 | |
750054a2 CT |
1442 | /* Make sure new block ends up in correct hot/cold section. */ |
1443 | ||
076c7ab8 | 1444 | BB_COPY_PARTITION (jump_block, e->src); |
9fb32434 | 1445 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1446 | && targetm_common.have_named_sections |
87c8b4be CT |
1447 | && JUMP_P (BB_END (jump_block)) |
1448 | && !any_condjump_p (BB_END (jump_block)) | |
1449 | && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING)) | |
65c5f2a6 | 1450 | add_reg_note (BB_END (jump_block), REG_CROSSING_JUMP, NULL_RTX); |
c22cacf3 | 1451 | |
ca6c03ca JH |
1452 | /* Wire edge in. */ |
1453 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
a3e6a37b JJ |
1454 | new_edge->probability = probability; |
1455 | new_edge->count = count; | |
ca6c03ca JH |
1456 | |
1457 | /* Redirect old edge. */ | |
1458 | redirect_edge_pred (e, jump_block); | |
1459 | e->probability = REG_BR_PROB_BASE; | |
1460 | ||
a3e6a37b JJ |
1461 | /* If asm goto has any label refs to target's label, |
1462 | add also edge from asm goto bb to target. */ | |
1463 | if (asm_goto_edge) | |
1464 | { | |
1465 | new_edge->probability /= 2; | |
1466 | new_edge->count /= 2; | |
1467 | jump_block->count /= 2; | |
1468 | jump_block->frequency /= 2; | |
1469 | new_edge = make_edge (new_edge->src, target, | |
1470 | e->flags & ~EDGE_FALLTHRU); | |
1471 | new_edge->probability = probability - probability / 2; | |
1472 | new_edge->count = count - count / 2; | |
1473 | } | |
1474 | ||
ca6c03ca JH |
1475 | new_bb = jump_block; |
1476 | } | |
1477 | else | |
1478 | jump_block = e->src; | |
5f0d2358 | 1479 | |
2f13f2de | 1480 | loc = e->goto_locus; |
ca6c03ca JH |
1481 | e->flags &= ~EDGE_FALLTHRU; |
1482 | if (target == EXIT_BLOCK_PTR) | |
1483 | { | |
26898771 BS |
1484 | if (jump_label == ret_rtx) |
1485 | { | |
cf22ce3c | 1486 | #ifdef HAVE_return |
26898771 | 1487 | emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc); |
cf22ce3c | 1488 | #else |
26898771 | 1489 | gcc_unreachable (); |
cf22ce3c | 1490 | #endif |
26898771 BS |
1491 | } |
1492 | else | |
1493 | { | |
1494 | gcc_assert (jump_label == simple_return_rtx); | |
1495 | #ifdef HAVE_simple_return | |
1496 | emit_jump_insn_after_setloc (gen_simple_return (), | |
1497 | BB_END (jump_block), loc); | |
1498 | #else | |
1499 | gcc_unreachable (); | |
1500 | #endif | |
1501 | } | |
387748de | 1502 | set_return_jump_label (BB_END (jump_block)); |
ca6c03ca JH |
1503 | } |
1504 | else | |
1505 | { | |
1506 | rtx label = block_label (target); | |
7241571e | 1507 | emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc); |
a813c111 | 1508 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1509 | LABEL_NUSES (label)++; |
1510 | } | |
5f0d2358 | 1511 | |
a813c111 | 1512 | emit_barrier_after (BB_END (jump_block)); |
ca6c03ca JH |
1513 | redirect_edge_succ_nodup (e, target); |
1514 | ||
a3716585 JH |
1515 | if (abnormal_edge_flags) |
1516 | make_edge (src, target, abnormal_edge_flags); | |
1517 | ||
b8698a0f | 1518 | df_mark_solutions_dirty (); |
ca6c03ca JH |
1519 | return new_bb; |
1520 | } | |
1521 | ||
1522 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1523 | (and possibly create new basic block) to make edge non-fallthru. | |
1524 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1525 | |
cf103ca4 EB |
1526 | static basic_block |
1527 | rtl_force_nonfallthru (edge e) | |
ca6c03ca | 1528 | { |
26898771 | 1529 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
ca6c03ca JH |
1530 | } |
1531 | ||
1532 | /* Redirect edge even at the expense of creating new jump insn or | |
1533 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1534 | Conversion must be possible. */ |
ca6c03ca | 1535 | |
9ee634e3 | 1536 | static basic_block |
d329e058 | 1537 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1538 | { |
5f0d2358 RK |
1539 | if (redirect_edge_and_branch (e, target) |
1540 | || e->dest == target) | |
ca6c03ca JH |
1541 | return NULL; |
1542 | ||
1543 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1544 | and redirect newly created simplejump. */ | |
6fb5fa3c | 1545 | df_set_bb_dirty (e->src); |
26898771 | 1546 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
ca6c03ca JH |
1547 | } |
1548 | ||
1549 | /* The given edge should potentially be a fallthru edge. If that is in | |
1550 | fact true, delete the jump and barriers that are in the way. */ | |
1551 | ||
f470c378 ZD |
1552 | static void |
1553 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1554 | { |
1555 | rtx q; | |
f470c378 ZD |
1556 | basic_block b = e->src, c = b->next_bb; |
1557 | ||
ca6c03ca JH |
1558 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1559 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1560 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1561 | |
1562 | We can also wind up with a sequence of undeletable labels between | |
1563 | one block and the next. | |
1564 | ||
1565 | So search through a sequence of barriers, labels, and notes for | |
1566 | the head of block C and assert that we really do fall through. */ | |
1567 | ||
a813c111 | 1568 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1569 | if (INSN_P (q)) |
1570 | return; | |
ca6c03ca JH |
1571 | |
1572 | /* Remove what will soon cease being the jump insn from the source block. | |
1573 | If block B consisted only of this single jump, turn it into a deleted | |
1574 | note. */ | |
a813c111 | 1575 | q = BB_END (b); |
4b4bf941 | 1576 | if (JUMP_P (q) |
ca6c03ca JH |
1577 | && onlyjump_p (q) |
1578 | && (any_uncondjump_p (q) | |
c5cbcccf | 1579 | || single_succ_p (b))) |
ca6c03ca JH |
1580 | { |
1581 | #ifdef HAVE_cc0 | |
1582 | /* If this was a conditional jump, we need to also delete | |
1583 | the insn that set cc0. */ | |
1584 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1585 | q = PREV_INSN (q); | |
1586 | #endif | |
1587 | ||
1588 | q = PREV_INSN (q); | |
ca6c03ca JH |
1589 | } |
1590 | ||
1591 | /* Selectively unlink the sequence. */ | |
a813c111 | 1592 | if (q != PREV_INSN (BB_HEAD (c))) |
a7b87f73 | 1593 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
ca6c03ca JH |
1594 | |
1595 | e->flags |= EDGE_FALLTHRU; | |
1596 | } | |
ca6c03ca | 1597 | \f |
f470c378 ZD |
1598 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1599 | ||
1600 | static bool | |
1601 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1602 | basic_block after ATTRIBUTE_UNUSED) | |
1603 | { | |
1604 | return false; | |
1605 | } | |
1606 | ||
ca6c03ca | 1607 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1608 | The edge must not be abnormal. |
ca6c03ca JH |
1609 | |
1610 | ??? The code generally expects to be called on critical edges. | |
1611 | The case of a block ending in an unconditional jump to a | |
1612 | block with multiple predecessors is not handled optimally. */ | |
1613 | ||
8ce33230 | 1614 | static basic_block |
d329e058 | 1615 | rtl_split_edge (edge edge_in) |
ca6c03ca JH |
1616 | { |
1617 | basic_block bb; | |
ca6c03ca JH |
1618 | rtx before; |
1619 | ||
1620 | /* Abnormal edges cannot be split. */ | |
341c100f | 1621 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1622 | |
1623 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1624 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1625 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1626 | { | |
0fd4b31d | 1627 | edge e = find_fallthru_edge (edge_in->dest->preds); |
ca6c03ca JH |
1628 | |
1629 | if (e) | |
1630 | force_nonfallthru (e); | |
1631 | } | |
1632 | ||
96e82e0a ZD |
1633 | /* Create the basic block note. */ |
1634 | if (edge_in->dest != EXIT_BLOCK_PTR) | |
a813c111 | 1635 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1636 | else |
1637 | before = NULL_RTX; | |
1638 | ||
623a66fa | 1639 | /* If this is a fall through edge to the exit block, the blocks might be |
ffe14686 AM |
1640 | not adjacent, and the right place is after the source. */ |
1641 | if ((edge_in->flags & EDGE_FALLTHRU) && edge_in->dest == EXIT_BLOCK_PTR) | |
623a66fa R |
1642 | { |
1643 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1644 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1645 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1646 | } |
1647 | else | |
9fb32434 CT |
1648 | { |
1649 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
076c7ab8 ZW |
1650 | /* ??? Why not edge_in->dest->prev_bb here? */ |
1651 | BB_COPY_PARTITION (bb, edge_in->dest); | |
9fb32434 | 1652 | } |
ca6c03ca | 1653 | |
4977bab6 | 1654 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1655 | |
4d6922ee | 1656 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1657 | jump instruction to target our new block. */ |
1658 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1659 | { | |
341c100f NS |
1660 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1661 | gcc_assert (redirected); | |
ca6c03ca JH |
1662 | } |
1663 | else | |
3b5fda81 JJ |
1664 | { |
1665 | if (edge_in->src != ENTRY_BLOCK_PTR) | |
1666 | { | |
1667 | /* For asm goto even splitting of fallthru edge might | |
1668 | need insn patching, as other labels might point to the | |
1669 | old label. */ | |
1670 | rtx last = BB_END (edge_in->src); | |
1671 | if (last | |
1672 | && JUMP_P (last) | |
1673 | && edge_in->dest != EXIT_BLOCK_PTR | |
1674 | && extract_asm_operands (PATTERN (last)) != NULL_RTX | |
1675 | && patch_jump_insn (last, before, bb)) | |
1676 | df_set_bb_dirty (edge_in->src); | |
1677 | } | |
1678 | redirect_edge_succ (edge_in, bb); | |
1679 | } | |
ca6c03ca JH |
1680 | |
1681 | return bb; | |
1682 | } | |
1683 | ||
1684 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1685 | The new instructions and basic blocks (if any) will not appear in the | |
1686 | CFG until commit_edge_insertions is called. */ | |
1687 | ||
1688 | void | |
d329e058 | 1689 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1690 | { |
1691 | /* We cannot insert instructions on an abnormal critical edge. | |
1692 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1693 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1694 | |
6de9cd9a | 1695 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1696 | start_sequence (); |
1697 | else | |
6de9cd9a | 1698 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1699 | |
1700 | emit_insn (pattern); | |
1701 | ||
6de9cd9a | 1702 | e->insns.r = get_insns (); |
ca6c03ca JH |
1703 | end_sequence (); |
1704 | } | |
1705 | ||
1706 | /* Update the CFG for the instructions queued on edge E. */ | |
1707 | ||
4e3825db | 1708 | void |
2ac66157 | 1709 | commit_one_edge_insertion (edge e) |
ca6c03ca JH |
1710 | { |
1711 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
898c90c0 | 1712 | basic_block bb; |
ca6c03ca JH |
1713 | |
1714 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1715 | insns = e->insns.r; |
1716 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1717 | |
898c90c0 EB |
1718 | /* Figure out where to put these insns. If the destination has |
1719 | one predecessor, insert there. Except for the exit block. */ | |
1720 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR) | |
ca6c03ca | 1721 | { |
898c90c0 EB |
1722 | bb = e->dest; |
1723 | ||
1724 | /* Get the location correct wrt a code label, and "nice" wrt | |
1725 | a basic block note, and before everything else. */ | |
1726 | tmp = BB_HEAD (bb); | |
1727 | if (LABEL_P (tmp)) | |
1728 | tmp = NEXT_INSN (tmp); | |
1729 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1730 | tmp = NEXT_INSN (tmp); | |
1731 | if (tmp == BB_HEAD (bb)) | |
1732 | before = tmp; | |
1733 | else if (tmp) | |
1734 | after = PREV_INSN (tmp); | |
1735 | else | |
1736 | after = get_last_insn (); | |
1737 | } | |
3dec4024 | 1738 | |
898c90c0 EB |
1739 | /* If the source has one successor and the edge is not abnormal, |
1740 | insert there. Except for the entry block. */ | |
1741 | else if ((e->flags & EDGE_ABNORMAL) == 0 | |
1742 | && single_succ_p (e->src) | |
1743 | && e->src != ENTRY_BLOCK_PTR) | |
1744 | { | |
1745 | bb = e->src; | |
3dec4024 | 1746 | |
898c90c0 EB |
1747 | /* It is possible to have a non-simple jump here. Consider a target |
1748 | where some forms of unconditional jumps clobber a register. This | |
1749 | happens on the fr30 for example. | |
ca6c03ca | 1750 | |
898c90c0 EB |
1751 | We know this block has a single successor, so we can just emit |
1752 | the queued insns before the jump. */ | |
1753 | if (JUMP_P (BB_END (bb))) | |
1754 | before = BB_END (bb); | |
3dec4024 JH |
1755 | else |
1756 | { | |
898c90c0 EB |
1757 | /* We'd better be fallthru, or we've lost track of what's what. */ |
1758 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
750054a2 | 1759 | |
898c90c0 | 1760 | after = BB_END (bb); |
ca6c03ca JH |
1761 | } |
1762 | } | |
1763 | ||
898c90c0 EB |
1764 | /* Otherwise we must split the edge. */ |
1765 | else | |
1766 | { | |
1767 | bb = split_edge (e); | |
1768 | after = BB_END (bb); | |
ca6c03ca | 1769 | |
898c90c0 | 1770 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1771 | && targetm_common.have_named_sections |
898c90c0 EB |
1772 | && e->src != ENTRY_BLOCK_PTR |
1773 | && BB_PARTITION (e->src) == BB_COLD_PARTITION | |
1774 | && !(e->flags & EDGE_CROSSING) | |
1775 | && JUMP_P (after) | |
1776 | && !any_condjump_p (after) | |
1777 | && (single_succ_edge (bb)->flags & EDGE_CROSSING)) | |
1778 | add_reg_note (after, REG_CROSSING_JUMP, NULL_RTX); | |
1779 | } | |
1780 | ||
1781 | /* Now that we've found the spot, do the insertion. */ | |
ca6c03ca JH |
1782 | if (before) |
1783 | { | |
6fb5fa3c | 1784 | emit_insn_before_noloc (insns, before, bb); |
ca6c03ca JH |
1785 | last = prev_nonnote_insn (before); |
1786 | } | |
1787 | else | |
6fb5fa3c | 1788 | last = emit_insn_after_noloc (insns, after, bb); |
ca6c03ca JH |
1789 | |
1790 | if (returnjump_p (last)) | |
1791 | { | |
1792 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
1793 | This is not currently a problem because this only happens |
1794 | for the (single) epilogue, which already has a fallthru edge | |
1795 | to EXIT. */ | |
ca6c03ca | 1796 | |
c5cbcccf | 1797 | e = single_succ_edge (bb); |
341c100f | 1798 | gcc_assert (e->dest == EXIT_BLOCK_PTR |
c5cbcccf | 1799 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 1800 | |
5f0d2358 | 1801 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 1802 | emit_barrier_after (last); |
0b17ab2f | 1803 | |
ca6c03ca JH |
1804 | if (before) |
1805 | delete_insn (before); | |
1806 | } | |
341c100f NS |
1807 | else |
1808 | gcc_assert (!JUMP_P (last)); | |
ca6c03ca JH |
1809 | } |
1810 | ||
1811 | /* Update the CFG for all queued instructions. */ | |
1812 | ||
1813 | void | |
d329e058 | 1814 | commit_edge_insertions (void) |
ca6c03ca | 1815 | { |
ca6c03ca JH |
1816 | basic_block bb; |
1817 | ||
1818 | #ifdef ENABLE_CHECKING | |
1819 | verify_flow_info (); | |
1820 | #endif | |
1821 | ||
e0082a72 | 1822 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
ca6c03ca | 1823 | { |
628f6a4e BE |
1824 | edge e; |
1825 | edge_iterator ei; | |
ca6c03ca | 1826 | |
628f6a4e BE |
1827 | FOR_EACH_EDGE (e, ei, bb->succs) |
1828 | if (e->insns.r) | |
cf103ca4 | 1829 | commit_one_edge_insertion (e); |
3dec4024 | 1830 | } |
ca6c03ca JH |
1831 | } |
1832 | \f | |
6fb5fa3c | 1833 | |
f470c378 | 1834 | /* Print out RTL-specific basic block information (live information |
a315c44c SB |
1835 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
1836 | documented in dumpfile.h. */ | |
ca6c03ca | 1837 | |
10e9fecc | 1838 | static void |
a315c44c | 1839 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags) |
ca6c03ca JH |
1840 | { |
1841 | rtx insn; | |
1842 | rtx last; | |
f470c378 | 1843 | char *s_indent; |
ca6c03ca | 1844 | |
ae50c0cb | 1845 | s_indent = (char *) alloca ((size_t) indent + 1); |
400e39e3 | 1846 | memset (s_indent, ' ', (size_t) indent); |
f470c378 | 1847 | s_indent[indent] = '\0'; |
b8698a0f | 1848 | |
a315c44c | 1849 | if (df && (flags & TDF_DETAILS)) |
6fb5fa3c DB |
1850 | { |
1851 | df_dump_top (bb, outf); | |
1852 | putc ('\n', outf); | |
1853 | } | |
ca6c03ca | 1854 | |
68cc3174 EB |
1855 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK) |
1856 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; | |
1857 | insn = NEXT_INSN (insn)) | |
a315c44c | 1858 | { |
7b19209f SB |
1859 | if (flags & TDF_DETAILS) |
1860 | df_dump_insn_top (insn, outf); | |
a315c44c SB |
1861 | if (! (flags & TDF_SLIM)) |
1862 | print_rtl_single (outf, insn); | |
1863 | else | |
1864 | dump_insn_slim (outf, insn); | |
7b19209f SB |
1865 | if (flags & TDF_DETAILS) |
1866 | df_dump_insn_bottom (insn, outf); | |
a315c44c SB |
1867 | } |
1868 | ||
1869 | if (df && (flags & TDF_DETAILS)) | |
6fb5fa3c DB |
1870 | { |
1871 | df_dump_bottom (bb, outf); | |
1872 | putc ('\n', outf); | |
1873 | } | |
1874 | ||
ca6c03ca JH |
1875 | } |
1876 | \f | |
c4669594 SB |
1877 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
1878 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
1879 | in dumpfile.h. */ | |
ca6c03ca JH |
1880 | |
1881 | void | |
a315c44c | 1882 | print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags) |
ca6c03ca | 1883 | { |
22ea9ec0 | 1884 | const_rtx tmp_rtx; |
ca6c03ca JH |
1885 | if (rtx_first == 0) |
1886 | fprintf (outf, "(nil)\n"); | |
1887 | else | |
1888 | { | |
ca6c03ca JH |
1889 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
1890 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
1891 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
1892 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
1893 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
e0082a72 ZD |
1894 | basic_block bb; |
1895 | ||
c4669594 SB |
1896 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
1897 | insns, but the CFG is not maintained so the basic block info | |
1898 | is not reliable. Therefore it's omitted from the dumps. */ | |
1899 | if (! (cfun->curr_properties & PROP_cfg)) | |
1900 | flags &= ~TDF_BLOCKS; | |
1901 | ||
6fb5fa3c DB |
1902 | if (df) |
1903 | df_dump_start (outf); | |
1904 | ||
c4669594 | 1905 | if (flags & TDF_BLOCKS) |
ca6c03ca | 1906 | { |
c4669594 | 1907 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1908 | { |
c4669594 SB |
1909 | rtx x; |
1910 | ||
1911 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
1912 | end[INSN_UID (BB_END (bb))] = bb; | |
1913 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
1914 | { | |
1915 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 1916 | |
c4669594 SB |
1917 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
1918 | state = IN_ONE_BB; | |
1919 | in_bb_p[INSN_UID (x)] = state; | |
ca6c03ca | 1920 | |
c4669594 SB |
1921 | if (x == BB_END (bb)) |
1922 | break; | |
1923 | } | |
ca6c03ca JH |
1924 | } |
1925 | } | |
1926 | ||
1927 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
1928 | { | |
c4669594 SB |
1929 | if (flags & TDF_BLOCKS) |
1930 | { | |
1931 | bb = start[INSN_UID (tmp_rtx)]; | |
1932 | if (bb != NULL) | |
1933 | { | |
1934 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false); | |
1935 | if (df && (flags & TDF_DETAILS)) | |
1936 | df_dump_top (bb, outf); | |
1937 | } | |
ca6c03ca | 1938 | |
c4669594 SB |
1939 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
1940 | && !NOTE_P (tmp_rtx) | |
1941 | && !BARRIER_P (tmp_rtx)) | |
1942 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
1943 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
1944 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
1945 | } | |
ca6c03ca | 1946 | |
7b19209f SB |
1947 | if (flags & TDF_DETAILS) |
1948 | df_dump_insn_top (tmp_rtx, outf); | |
a315c44c SB |
1949 | if (! (flags & TDF_SLIM)) |
1950 | print_rtl_single (outf, tmp_rtx); | |
1951 | else | |
1952 | dump_insn_slim (outf, tmp_rtx); | |
7b19209f SB |
1953 | if (flags & TDF_DETAILS) |
1954 | df_dump_insn_bottom (tmp_rtx, outf); | |
ca6c03ca | 1955 | |
c4669594 SB |
1956 | if (flags & TDF_BLOCKS) |
1957 | { | |
1958 | bb = end[INSN_UID (tmp_rtx)]; | |
1959 | if (bb != NULL) | |
1960 | { | |
1961 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true); | |
1962 | if (df && (flags & TDF_DETAILS)) | |
1963 | df_dump_bottom (bb, outf); | |
1b03a96d | 1964 | putc ('\n', outf); |
c4669594 SB |
1965 | } |
1966 | } | |
ca6c03ca JH |
1967 | } |
1968 | ||
1969 | free (start); | |
1970 | free (end); | |
1971 | free (in_bb_p); | |
1972 | } | |
1973 | ||
cb91fab0 | 1974 | if (crtl->epilogue_delay_list != 0) |
ca6c03ca JH |
1975 | { |
1976 | fprintf (outf, "\n;; Insns in epilogue delay list:\n\n"); | |
cb91fab0 | 1977 | for (tmp_rtx = crtl->epilogue_delay_list; tmp_rtx != 0; |
ca6c03ca JH |
1978 | tmp_rtx = XEXP (tmp_rtx, 1)) |
1979 | print_rtl_single (outf, XEXP (tmp_rtx, 0)); | |
1980 | } | |
1981 | } | |
1982 | \f | |
532aafad SB |
1983 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
1984 | ||
b446e5a2 | 1985 | void |
d329e058 | 1986 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
1987 | { |
1988 | rtx note; | |
4b4bf941 | 1989 | if (!JUMP_P (BB_END (bb))) |
b446e5a2 | 1990 | return; |
a813c111 | 1991 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
b446e5a2 JH |
1992 | if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability) |
1993 | return; | |
1994 | XEXP (note, 0) = GEN_INT (BRANCH_EDGE (bb)->probability); | |
1995 | } | |
96370780 MK |
1996 | |
1997 | /* Get the last insn associated with block BB (that includes barriers and | |
1998 | tablejumps after BB). */ | |
1999 | rtx | |
2000 | get_last_bb_insn (basic_block bb) | |
2001 | { | |
2002 | rtx tmp; | |
2003 | rtx end = BB_END (bb); | |
2004 | ||
2005 | /* Include any jump table following the basic block. */ | |
2006 | if (tablejump_p (end, NULL, &tmp)) | |
2007 | end = tmp; | |
2008 | ||
2009 | /* Include any barriers that may follow the basic block. */ | |
1e211590 | 2010 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2011 | while (tmp && BARRIER_P (tmp)) |
2012 | { | |
2013 | end = tmp; | |
1e211590 | 2014 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2015 | } |
2016 | ||
2017 | return end; | |
2018 | } | |
b446e5a2 | 2019 | \f |
10e9fecc JH |
2020 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2021 | cfglayout RTL. | |
ca6c03ca JH |
2022 | |
2023 | Currently it does following checks: | |
2024 | ||
ca6c03ca | 2025 | - overlapping of basic blocks |
9eab6785 | 2026 | - insns with wrong BLOCK_FOR_INSN pointers |
ca6c03ca | 2027 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) |
f63d1bf7 | 2028 | - tails of basic blocks (ensure that boundary is necessary) |
ca6c03ca JH |
2029 | - scans body of the basic block for JUMP_INSN, CODE_LABEL |
2030 | and NOTE_INSN_BASIC_BLOCK | |
750054a2 | 2031 | - verify that no fall_thru edge crosses hot/cold partition boundaries |
9eab6785 | 2032 | - verify that there are no pending RTL branch predictions |
ca6c03ca JH |
2033 | |
2034 | In future it can be extended check a lot of other stuff as well | |
2035 | (reachability of basic blocks, life information, etc. etc.). */ | |
f470c378 | 2036 | |
10e9fecc | 2037 | static int |
d329e058 | 2038 | rtl_verify_flow_info_1 (void) |
ca6c03ca | 2039 | { |
ca6c03ca | 2040 | rtx x; |
10e9fecc | 2041 | int err = 0; |
94eb5ddb | 2042 | basic_block bb; |
ca6c03ca | 2043 | |
9eab6785 | 2044 | /* Check the general integrity of the basic blocks. */ |
e0082a72 | 2045 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2046 | { |
9eab6785 | 2047 | rtx insn; |
5f0d2358 | 2048 | |
5e2d947c JH |
2049 | if (!(bb->flags & BB_RTL)) |
2050 | { | |
2051 | error ("BB_RTL flag not set for block %d", bb->index); | |
2052 | err = 1; | |
2053 | } | |
2054 | ||
9eab6785 | 2055 | FOR_BB_INSNS (bb, insn) |
8ce9fd5d | 2056 | if (BLOCK_FOR_INSN (insn) != bb) |
9eab6785 SB |
2057 | { |
2058 | error ("insn %d basic block pointer is %d, should be %d", | |
2059 | INSN_UID (insn), | |
2060 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2061 | bb->index); | |
2062 | err = 1; | |
2063 | } | |
a7b87f73 | 2064 | |
bcc708fc | 2065 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2066 | if (!BARRIER_P (insn) |
2067 | && BLOCK_FOR_INSN (insn) != NULL) | |
2068 | { | |
2069 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2070 | INSN_UID (insn), bb->index); | |
2071 | err = 1; | |
2072 | } | |
bcc708fc | 2073 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2074 | if (!BARRIER_P (insn) |
2075 | && BLOCK_FOR_INSN (insn) != NULL) | |
2076 | { | |
2077 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2078 | INSN_UID (insn), bb->index); | |
2079 | err = 1; | |
2080 | } | |
ca6c03ca JH |
2081 | } |
2082 | ||
2083 | /* Now check the basic blocks (boundaries etc.) */ | |
e0082a72 | 2084 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2085 | { |
3dec4024 | 2086 | int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0; |
3cf54412 | 2087 | edge e, fallthru = NULL; |
5a1a3e5e | 2088 | rtx note; |
628f6a4e | 2089 | edge_iterator ei; |
ca6c03ca | 2090 | |
2085a21f | 2091 | if (JUMP_P (BB_END (bb)) |
a813c111 | 2092 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 2093 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 2094 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 2095 | { |
e53de54d JH |
2096 | if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability |
2097 | && profile_status != PROFILE_ABSENT) | |
5a1a3e5e | 2098 | { |
0108ae51 | 2099 | error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i", |
5a1a3e5e JH |
2100 | INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability); |
2101 | err = 1; | |
2102 | } | |
2103 | } | |
628f6a4e | 2104 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 2105 | { |
0be7e7a6 RH |
2106 | bool is_crossing; |
2107 | ||
ca6c03ca | 2108 | if (e->flags & EDGE_FALLTHRU) |
0be7e7a6 RH |
2109 | n_fallthru++, fallthru = e; |
2110 | ||
2111 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
2112 | && e->src != ENTRY_BLOCK_PTR | |
2113 | && e->dest != EXIT_BLOCK_PTR); | |
2114 | if (e->flags & EDGE_CROSSING) | |
750054a2 | 2115 | { |
0be7e7a6 RH |
2116 | if (!is_crossing) |
2117 | { | |
2118 | error ("EDGE_CROSSING incorrectly set across same section"); | |
2119 | err = 1; | |
2120 | } | |
2121 | if (e->flags & EDGE_FALLTHRU) | |
2122 | { | |
ab532386 | 2123 | error ("fallthru edge crosses section boundary (bb %i)", |
750054a2 CT |
2124 | e->src->index); |
2125 | err = 1; | |
2126 | } | |
0be7e7a6 RH |
2127 | if (e->flags & EDGE_EH) |
2128 | { | |
2129 | error ("EH edge crosses section boundary (bb %i)", | |
2130 | e->src->index); | |
2131 | err = 1; | |
2132 | } | |
2133 | } | |
2134 | else if (is_crossing) | |
2135 | { | |
2136 | error ("EDGE_CROSSING missing across section boundary"); | |
2137 | err = 1; | |
750054a2 | 2138 | } |
3dec4024 | 2139 | |
65f43cdf ZD |
2140 | if ((e->flags & ~(EDGE_DFS_BACK |
2141 | | EDGE_CAN_FALLTHRU | |
2142 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 | 2143 | | EDGE_LOOP_EXIT |
7e872b90 JJ |
2144 | | EDGE_CROSSING |
2145 | | EDGE_PRESERVE)) == 0) | |
3dec4024 JH |
2146 | n_branch++; |
2147 | ||
2148 | if (e->flags & EDGE_ABNORMAL_CALL) | |
2149 | n_call++; | |
2150 | ||
2151 | if (e->flags & EDGE_EH) | |
2152 | n_eh++; | |
2153 | else if (e->flags & EDGE_ABNORMAL) | |
2154 | n_abnormal++; | |
ca6c03ca | 2155 | } |
5f0d2358 | 2156 | |
1d65f45c | 2157 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
3dec4024 | 2158 | { |
ab532386 | 2159 | error ("missing REG_EH_REGION note in the end of bb %i", bb->index); |
3dec4024 JH |
2160 | err = 1; |
2161 | } | |
1d65f45c RH |
2162 | if (n_eh > 1) |
2163 | { | |
2164 | error ("too many eh edges %i", bb->index); | |
2165 | err = 1; | |
2166 | } | |
3dec4024 | 2167 | if (n_branch |
4b4bf941 | 2168 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2169 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2170 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2171 | { |
ab532386 | 2172 | error ("too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
2173 | err = 1; |
2174 | } | |
a813c111 | 2175 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2176 | { |
ab532386 | 2177 | error ("fallthru edge after unconditional jump %i", bb->index); |
3dec4024 JH |
2178 | err = 1; |
2179 | } | |
a813c111 | 2180 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2181 | { |
1d65f45c RH |
2182 | error ("wrong number of branch edges after unconditional jump %i", |
2183 | bb->index); | |
3dec4024 JH |
2184 | err = 1; |
2185 | } | |
a813c111 | 2186 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 2187 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 2188 | { |
c11fd0b2 RG |
2189 | error ("wrong amount of branch edges after conditional jump %i", |
2190 | bb->index); | |
3dec4024 JH |
2191 | err = 1; |
2192 | } | |
4b4bf941 | 2193 | if (n_call && !CALL_P (BB_END (bb))) |
3dec4024 | 2194 | { |
ab532386 | 2195 | error ("call edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
2196 | err = 1; |
2197 | } | |
2198 | if (n_abnormal | |
4b4bf941 JQ |
2199 | && (!CALL_P (BB_END (bb)) && n_call != n_abnormal) |
2200 | && (!JUMP_P (BB_END (bb)) | |
a813c111 SB |
2201 | || any_condjump_p (BB_END (bb)) |
2202 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2203 | { |
ab532386 | 2204 | error ("abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
2205 | err = 1; |
2206 | } | |
f87c27b4 | 2207 | |
a813c111 | 2208 | for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x)) |
0ca541aa | 2209 | /* We may have a barrier inside a basic block before dead code |
9524880c HPN |
2210 | elimination. There is no BLOCK_FOR_INSN field in a barrier. */ |
2211 | if (!BARRIER_P (x) && BLOCK_FOR_INSN (x) != bb) | |
5f0d2358 RK |
2212 | { |
2213 | debug_rtx (x); | |
2214 | if (! BLOCK_FOR_INSN (x)) | |
2215 | error | |
2216 | ("insn %d inside basic block %d but block_for_insn is NULL", | |
0b17ab2f | 2217 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2218 | else |
2219 | error | |
2220 | ("insn %d inside basic block %d but block_for_insn is %i", | |
0b17ab2f | 2221 | INSN_UID (x), bb->index, BLOCK_FOR_INSN (x)->index); |
5f0d2358 RK |
2222 | |
2223 | err = 1; | |
2224 | } | |
ca6c03ca JH |
2225 | |
2226 | /* OK pointers are correct. Now check the header of basic | |
c22cacf3 | 2227 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 2228 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 2229 | x = BB_HEAD (bb); |
4b4bf941 | 2230 | if (LABEL_P (x)) |
ca6c03ca | 2231 | { |
a813c111 | 2232 | if (BB_END (bb) == x) |
ca6c03ca JH |
2233 | { |
2234 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2235 | bb->index); |
ca6c03ca JH |
2236 | err = 1; |
2237 | } | |
5f0d2358 | 2238 | |
ca6c03ca JH |
2239 | x = NEXT_INSN (x); |
2240 | } | |
5f0d2358 | 2241 | |
ca6c03ca JH |
2242 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2243 | { | |
2244 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2245 | bb->index); |
ca6c03ca JH |
2246 | err = 1; |
2247 | } | |
2248 | ||
a813c111 | 2249 | if (BB_END (bb) == x) |
49243025 | 2250 | /* Do checks for empty blocks here. */ |
5f0d2358 | 2251 | ; |
ca6c03ca | 2252 | else |
5f0d2358 RK |
2253 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2254 | { | |
2255 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2256 | { | |
2257 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2258 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2259 | err = 1; |
2260 | } | |
2261 | ||
a813c111 | 2262 | if (x == BB_END (bb)) |
5f0d2358 | 2263 | break; |
ca6c03ca | 2264 | |
83fd323c | 2265 | if (control_flow_insn_p (x)) |
5f0d2358 | 2266 | { |
0b17ab2f | 2267 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2268 | fatal_insn ("flow control insn inside a basic block", x); |
2269 | } | |
2270 | } | |
ca6c03ca JH |
2271 | } |
2272 | ||
10e9fecc | 2273 | /* Clean up. */ |
10e9fecc JH |
2274 | return err; |
2275 | } | |
5f0d2358 | 2276 | |
10e9fecc JH |
2277 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2278 | cfglayout RTL. | |
5f0d2358 | 2279 | |
10e9fecc JH |
2280 | Currently it does following checks: |
2281 | - all checks of rtl_verify_flow_info_1 | |
9eab6785 | 2282 | - test head/end pointers |
10e9fecc JH |
2283 | - check that all insns are in the basic blocks |
2284 | (except the switch handling code, barriers and notes) | |
2285 | - check that all returns are followed by barriers | |
2286 | - check that all fallthru edge points to the adjacent blocks. */ | |
9eab6785 | 2287 | |
10e9fecc | 2288 | static int |
d329e058 | 2289 | rtl_verify_flow_info (void) |
10e9fecc JH |
2290 | { |
2291 | basic_block bb; | |
2292 | int err = rtl_verify_flow_info_1 (); | |
2293 | rtx x; | |
9eab6785 SB |
2294 | rtx last_head = get_last_insn (); |
2295 | basic_block *bb_info; | |
10e9fecc JH |
2296 | int num_bb_notes; |
2297 | const rtx rtx_first = get_insns (); | |
2298 | basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL; | |
9eab6785 SB |
2299 | const int max_uid = get_max_uid (); |
2300 | ||
2301 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 2302 | |
10e9fecc JH |
2303 | FOR_EACH_BB_REVERSE (bb) |
2304 | { | |
2305 | edge e; | |
9eab6785 SB |
2306 | rtx head = BB_HEAD (bb); |
2307 | rtx end = BB_END (bb); | |
628f6a4e | 2308 | |
9eab6785 | 2309 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
a7b87f73 ZD |
2310 | { |
2311 | /* Verify the end of the basic block is in the INSN chain. */ | |
2312 | if (x == end) | |
2313 | break; | |
2314 | ||
2315 | /* And that the code outside of basic blocks has NULL bb field. */ | |
2316 | if (!BARRIER_P (x) | |
2317 | && BLOCK_FOR_INSN (x) != NULL) | |
2318 | { | |
2319 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2320 | INSN_UID (x)); | |
2321 | err = 1; | |
2322 | } | |
2323 | } | |
9eab6785 SB |
2324 | |
2325 | if (!x) | |
2326 | { | |
2327 | error ("end insn %d for block %d not found in the insn stream", | |
2328 | INSN_UID (end), bb->index); | |
2329 | err = 1; | |
2330 | } | |
2331 | ||
2332 | /* Work backwards from the end to the head of the basic block | |
2333 | to verify the head is in the RTL chain. */ | |
2334 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 2335 | { |
9eab6785 SB |
2336 | /* While walking over the insn chain, verify insns appear |
2337 | in only one basic block. */ | |
2338 | if (bb_info[INSN_UID (x)] != NULL) | |
2339 | { | |
2340 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2341 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
2342 | err = 1; | |
2343 | } | |
2344 | ||
2345 | bb_info[INSN_UID (x)] = bb; | |
2346 | ||
2347 | if (x == head) | |
2348 | break; | |
2349 | } | |
2350 | if (!x) | |
2351 | { | |
2352 | error ("head insn %d for block %d not found in the insn stream", | |
2353 | INSN_UID (head), bb->index); | |
a00d11f0 JH |
2354 | err = 1; |
2355 | } | |
2356 | ||
a7b87f73 | 2357 | last_head = PREV_INSN (x); |
9eab6785 | 2358 | |
0fd4b31d | 2359 | e = find_fallthru_edge (bb->succs); |
10e9fecc JH |
2360 | if (!e) |
2361 | { | |
2362 | rtx insn; | |
2363 | ||
2364 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
468059bc DD |
2365 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
2366 | { | |
2367 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
10e9fecc JH |
2368 | { |
2369 | error ("missing barrier after block %i", bb->index); | |
2370 | err = 1; | |
2371 | break; | |
2372 | } | |
468059bc DD |
2373 | if (BARRIER_P (insn)) |
2374 | break; | |
2375 | } | |
10e9fecc JH |
2376 | } |
2377 | else if (e->src != ENTRY_BLOCK_PTR | |
2378 | && e->dest != EXIT_BLOCK_PTR) | |
c22cacf3 | 2379 | { |
10e9fecc JH |
2380 | rtx insn; |
2381 | ||
2382 | if (e->src->next_bb != e->dest) | |
2383 | { | |
2384 | error | |
2385 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2386 | e->src->index, e->dest->index); | |
2387 | err = 1; | |
2388 | } | |
2389 | else | |
a813c111 | 2390 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 2391 | insn = NEXT_INSN (insn)) |
6be85b25 | 2392 | if (BARRIER_P (insn) || INSN_P (insn)) |
10e9fecc JH |
2393 | { |
2394 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2395 | e->src->index, e->dest->index); | |
2396 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2397 | err = 1; | |
2398 | } | |
c22cacf3 | 2399 | } |
10e9fecc | 2400 | } |
ca6c03ca | 2401 | |
a7b87f73 ZD |
2402 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
2403 | { | |
2404 | /* Check that the code before the first basic block has NULL | |
2405 | bb field. */ | |
2406 | if (!BARRIER_P (x) | |
2407 | && BLOCK_FOR_INSN (x) != NULL) | |
2408 | { | |
2409 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2410 | INSN_UID (x)); | |
2411 | err = 1; | |
2412 | } | |
2413 | } | |
9eab6785 SB |
2414 | free (bb_info); |
2415 | ||
ca6c03ca | 2416 | num_bb_notes = 0; |
e0082a72 ZD |
2417 | last_bb_seen = ENTRY_BLOCK_PTR; |
2418 | ||
5f0d2358 | 2419 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2420 | { |
2421 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2422 | { | |
bf77398c | 2423 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2424 | |
ca6c03ca | 2425 | num_bb_notes++; |
e0082a72 | 2426 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2427 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2428 | |
10e9fecc | 2429 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2430 | } |
2431 | ||
10e9fecc | 2432 | if (!curr_bb) |
ca6c03ca JH |
2433 | { |
2434 | switch (GET_CODE (x)) | |
2435 | { | |
2436 | case BARRIER: | |
2437 | case NOTE: | |
2438 | break; | |
2439 | ||
2440 | case CODE_LABEL: | |
666c27b9 | 2441 | /* An addr_vec is placed outside any basic block. */ |
ca6c03ca | 2442 | if (NEXT_INSN (x) |
481683e1 | 2443 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5f0d2358 | 2444 | x = NEXT_INSN (x); |
ca6c03ca JH |
2445 | |
2446 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2447 | break; | |
2448 | ||
2449 | default: | |
1f978f5f | 2450 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2451 | } |
2452 | } | |
2453 | ||
26cae194 | 2454 | if (JUMP_P (x) |
ca6c03ca | 2455 | && returnjump_p (x) && ! condjump_p (x) |
15eb3a2e | 2456 | && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x)))) |
1f978f5f | 2457 | fatal_insn ("return not followed by barrier", x); |
a813c111 | 2458 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2459 | curr_bb = NULL; |
ca6c03ca JH |
2460 | } |
2461 | ||
24bd1a0b | 2462 | if (num_bb_notes != n_basic_blocks - NUM_FIXED_BLOCKS) |
ca6c03ca | 2463 | internal_error |
0b17ab2f RH |
2464 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
2465 | num_bb_notes, n_basic_blocks); | |
ca6c03ca | 2466 | |
10e9fecc | 2467 | return err; |
ca6c03ca JH |
2468 | } |
2469 | \f | |
eaec9b3d | 2470 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2471 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2472 | Return true if any edges are eliminated. */ | |
2473 | ||
2474 | bool | |
d329e058 | 2475 | purge_dead_edges (basic_block bb) |
ca6c03ca | 2476 | { |
628f6a4e | 2477 | edge e; |
a813c111 | 2478 | rtx insn = BB_END (bb), note; |
ca6c03ca | 2479 | bool purged = false; |
628f6a4e BE |
2480 | bool found; |
2481 | edge_iterator ei; | |
ca6c03ca | 2482 | |
b5b8b0ac AO |
2483 | if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) |
2484 | do | |
2485 | insn = PREV_INSN (insn); | |
2486 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
2487 | ||
70da1d03 | 2488 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 2489 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
2490 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2491 | { | |
2492 | rtx eqnote; | |
2493 | ||
2494 | if (! may_trap_p (PATTERN (insn)) | |
2495 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2496 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
2497 | remove_note (insn, note); | |
2498 | } | |
2499 | ||
546c093e | 2500 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 2501 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 2502 | { |
1d65f45c RH |
2503 | bool remove = false; |
2504 | ||
e5f9a909 JW |
2505 | /* There are three types of edges we need to handle correctly here: EH |
2506 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
2507 | latter can appear when nonlocal gotos are used. */ | |
1d65f45c | 2508 | if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 2509 | { |
1d65f45c RH |
2510 | if (!CALL_P (insn)) |
2511 | remove = true; | |
2512 | else if (can_nonlocal_goto (insn)) | |
2513 | ; | |
2514 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
2515 | ; | |
0a35513e AH |
2516 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
2517 | ; | |
1d65f45c RH |
2518 | else |
2519 | remove = true; | |
546c093e | 2520 | } |
1d65f45c RH |
2521 | else if (e->flags & EDGE_EH) |
2522 | remove = !can_throw_internal (insn); | |
2523 | ||
2524 | if (remove) | |
546c093e | 2525 | { |
1d65f45c RH |
2526 | remove_edge (e); |
2527 | df_set_bb_dirty (bb); | |
2528 | purged = true; | |
546c093e RH |
2529 | } |
2530 | else | |
1d65f45c | 2531 | ei_next (&ei); |
546c093e | 2532 | } |
5f0d2358 | 2533 | |
4b4bf941 | 2534 | if (JUMP_P (insn)) |
ca6c03ca JH |
2535 | { |
2536 | rtx note; | |
2537 | edge b,f; | |
628f6a4e | 2538 | edge_iterator ei; |
5f0d2358 | 2539 | |
ca6c03ca JH |
2540 | /* We do care only about conditional jumps and simplejumps. */ |
2541 | if (!any_condjump_p (insn) | |
2542 | && !returnjump_p (insn) | |
2543 | && !simplejump_p (insn)) | |
c51d95ec | 2544 | return purged; |
5f0d2358 | 2545 | |
5a1a3e5e JH |
2546 | /* Branch probability/prediction notes are defined only for |
2547 | condjumps. We've possibly turned condjump into simplejump. */ | |
2548 | if (simplejump_p (insn)) | |
2549 | { | |
2550 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2551 | if (note) | |
2552 | remove_note (insn, note); | |
2553 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
2554 | remove_note (insn, note); | |
2555 | } | |
2556 | ||
628f6a4e | 2557 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2558 | { |
7fcd7218 JH |
2559 | /* Avoid abnormal flags to leak from computed jumps turned |
2560 | into simplejumps. */ | |
f87c27b4 | 2561 | |
0e1638d4 | 2562 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 2563 | |
5a566bed MM |
2564 | /* See if this edge is one we should keep. */ |
2565 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
2566 | /* A conditional jump can fall through into the next | |
2567 | block, so we should keep the edge. */ | |
628f6a4e BE |
2568 | { |
2569 | ei_next (&ei); | |
2570 | continue; | |
2571 | } | |
5f0d2358 | 2572 | else if (e->dest != EXIT_BLOCK_PTR |
a813c111 | 2573 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
2574 | /* If the destination block is the target of the jump, |
2575 | keep the edge. */ | |
628f6a4e BE |
2576 | { |
2577 | ei_next (&ei); | |
2578 | continue; | |
2579 | } | |
5a566bed MM |
2580 | else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn)) |
2581 | /* If the destination block is the exit block, and this | |
2582 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
2583 | { |
2584 | ei_next (&ei); | |
2585 | continue; | |
2586 | } | |
5a566bed MM |
2587 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
2588 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
2589 | this instruction and rematerialize the EDGE_ABNORMAL |
2590 | flag we just cleared above. */ | |
2591 | { | |
2592 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 2593 | ei_next (&ei); |
0b75beaa EB |
2594 | continue; |
2595 | } | |
5f0d2358 | 2596 | |
5a566bed | 2597 | /* We do not need this edge. */ |
6fb5fa3c | 2598 | df_set_bb_dirty (bb); |
ca6c03ca JH |
2599 | purged = true; |
2600 | remove_edge (e); | |
2601 | } | |
5f0d2358 | 2602 | |
628f6a4e | 2603 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 2604 | return purged; |
5f0d2358 | 2605 | |
c263766c RH |
2606 | if (dump_file) |
2607 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 2608 | |
ca6c03ca JH |
2609 | if (!optimize) |
2610 | return purged; | |
2611 | ||
2612 | /* Redistribute probabilities. */ | |
c5cbcccf | 2613 | if (single_succ_p (bb)) |
ca6c03ca | 2614 | { |
c5cbcccf ZD |
2615 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2616 | single_succ_edge (bb)->count = bb->count; | |
f87c27b4 | 2617 | } |
ca6c03ca JH |
2618 | else |
2619 | { | |
2620 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2621 | if (!note) | |
2622 | return purged; | |
5f0d2358 | 2623 | |
ca6c03ca JH |
2624 | b = BRANCH_EDGE (bb); |
2625 | f = FALLTHRU_EDGE (bb); | |
2626 | b->probability = INTVAL (XEXP (note, 0)); | |
2627 | f->probability = REG_BR_PROB_BASE - b->probability; | |
2628 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; | |
2629 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
2630 | } | |
5f0d2358 | 2631 | |
ca6c03ca JH |
2632 | return purged; |
2633 | } | |
4b4bf941 | 2634 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
2635 | { |
2636 | /* First, there should not be any EH or ABCALL edges resulting | |
2637 | from non-local gotos and the like. If there were, we shouldn't | |
2638 | have created the sibcall in the first place. Second, there | |
2639 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
2640 | gcc_assert (single_succ_p (bb)); |
2641 | gcc_assert (single_succ_edge (bb)->flags | |
2642 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 RH |
2643 | |
2644 | return 0; | |
2645 | } | |
ca6c03ca | 2646 | |
ca6c03ca JH |
2647 | /* If we don't see a jump insn, we don't know exactly why the block would |
2648 | have been broken at this point. Look for a simple, non-fallthru edge, | |
2649 | as these are only created by conditional branches. If we find such an | |
2650 | edge we know that there used to be a jump here and can then safely | |
2651 | remove all non-fallthru edges. */ | |
628f6a4e BE |
2652 | found = false; |
2653 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2654 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
2655 | { | |
2656 | found = true; | |
2657 | break; | |
2658 | } | |
5f0d2358 | 2659 | |
628f6a4e | 2660 | if (!found) |
ca6c03ca | 2661 | return purged; |
5f0d2358 | 2662 | |
2afa8dce DB |
2663 | /* Remove all but the fake and fallthru edges. The fake edge may be |
2664 | the only successor for this block in the case of noreturn | |
2665 | calls. */ | |
628f6a4e | 2666 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2667 | { |
2afa8dce | 2668 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec | 2669 | { |
6fb5fa3c | 2670 | df_set_bb_dirty (bb); |
c51d95ec JH |
2671 | remove_edge (e); |
2672 | purged = true; | |
2673 | } | |
628f6a4e BE |
2674 | else |
2675 | ei_next (&ei); | |
ca6c03ca | 2676 | } |
5f0d2358 | 2677 | |
c5cbcccf | 2678 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 2679 | |
c5cbcccf ZD |
2680 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2681 | single_succ_edge (bb)->count = bb->count; | |
ca6c03ca | 2682 | |
c263766c RH |
2683 | if (dump_file) |
2684 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 2685 | bb->index); |
ca6c03ca JH |
2686 | return purged; |
2687 | } | |
2688 | ||
5f0d2358 RK |
2689 | /* Search all basic blocks for potentially dead edges and purge them. Return |
2690 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
2691 | |
2692 | bool | |
25cd19de | 2693 | purge_all_dead_edges (void) |
ca6c03ca | 2694 | { |
e0082a72 | 2695 | int purged = false; |
e0082a72 | 2696 | basic_block bb; |
473fb060 | 2697 | |
e0082a72 | 2698 | FOR_EACH_BB (bb) |
473fb060 | 2699 | { |
e0082a72 | 2700 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 2701 | |
473fb060 | 2702 | purged |= purged_here; |
473fb060 | 2703 | } |
5f0d2358 | 2704 | |
ca6c03ca JH |
2705 | return purged; |
2706 | } | |
9ee634e3 | 2707 | |
ba5e9aca EB |
2708 | /* This is used by a few passes that emit some instructions after abnormal |
2709 | calls, moving the basic block's end, while they in fact do want to emit | |
2710 | them on the fallthru edge. Look for abnormal call edges, find backward | |
2711 | the call in the block and insert the instructions on the edge instead. | |
2712 | ||
2713 | Similarly, handle instructions throwing exceptions internally. | |
2714 | ||
2715 | Return true when instructions have been found and inserted on edges. */ | |
2716 | ||
2717 | bool | |
2718 | fixup_abnormal_edges (void) | |
2719 | { | |
2720 | bool inserted = false; | |
2721 | basic_block bb; | |
2722 | ||
2723 | FOR_EACH_BB (bb) | |
2724 | { | |
2725 | edge e; | |
2726 | edge_iterator ei; | |
2727 | ||
2728 | /* Look for cases we are interested in - calls or instructions causing | |
2729 | exceptions. */ | |
2730 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2731 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
2732 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
2733 | == (EDGE_ABNORMAL | EDGE_EH))) | |
2734 | break; | |
2735 | ||
2736 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
2737 | { | |
2738 | rtx insn; | |
2739 | ||
2740 | /* Get past the new insns generated. Allow notes, as the insns | |
2741 | may be already deleted. */ | |
2742 | insn = BB_END (bb); | |
2743 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
2744 | && !can_throw_internal (insn) | |
2745 | && insn != BB_HEAD (bb)) | |
2746 | insn = PREV_INSN (insn); | |
2747 | ||
2748 | if (CALL_P (insn) || can_throw_internal (insn)) | |
2749 | { | |
2750 | rtx stop, next; | |
2751 | ||
2752 | e = find_fallthru_edge (bb->succs); | |
2753 | ||
2754 | stop = NEXT_INSN (BB_END (bb)); | |
2755 | BB_END (bb) = insn; | |
2756 | ||
2757 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
2758 | { | |
2759 | next = NEXT_INSN (insn); | |
2760 | if (INSN_P (insn)) | |
2761 | { | |
2762 | delete_insn (insn); | |
2763 | ||
2764 | /* Sometimes there's still the return value USE. | |
2765 | If it's placed after a trapping call (i.e. that | |
2766 | call is the last insn anyway), we have no fallthru | |
2767 | edge. Simply delete this use and don't try to insert | |
2768 | on the non-existent edge. */ | |
2769 | if (GET_CODE (PATTERN (insn)) != USE) | |
2770 | { | |
2771 | /* We're not deleting it, we're moving it. */ | |
2772 | INSN_DELETED_P (insn) = 0; | |
2773 | PREV_INSN (insn) = NULL_RTX; | |
2774 | NEXT_INSN (insn) = NULL_RTX; | |
2775 | ||
2776 | insert_insn_on_edge (insn, e); | |
2777 | inserted = true; | |
2778 | } | |
2779 | } | |
2780 | else if (!BARRIER_P (insn)) | |
2781 | set_block_for_insn (insn, NULL); | |
2782 | } | |
2783 | } | |
2784 | ||
2785 | /* It may be that we don't find any trapping insn. In this | |
2786 | case we discovered quite late that the insn that had been | |
2787 | marked as can_throw_internal in fact couldn't trap at all. | |
2788 | So we should in fact delete the EH edges out of the block. */ | |
2789 | else | |
2790 | purge_dead_edges (bb); | |
2791 | } | |
2792 | } | |
2793 | ||
2794 | return inserted; | |
2795 | } | |
78bde837 SB |
2796 | \f |
2797 | /* Cut the insns from FIRST to LAST out of the insns stream. */ | |
2798 | ||
2799 | rtx | |
2800 | unlink_insn_chain (rtx first, rtx last) | |
2801 | { | |
2802 | rtx prevfirst = PREV_INSN (first); | |
2803 | rtx nextlast = NEXT_INSN (last); | |
2804 | ||
2805 | PREV_INSN (first) = NULL; | |
2806 | NEXT_INSN (last) = NULL; | |
2807 | if (prevfirst) | |
2808 | NEXT_INSN (prevfirst) = nextlast; | |
2809 | if (nextlast) | |
2810 | PREV_INSN (nextlast) = prevfirst; | |
2811 | else | |
2812 | set_last_insn (prevfirst); | |
2813 | if (!prevfirst) | |
2814 | set_first_insn (nextlast); | |
2815 | return first; | |
2816 | } | |
2817 | \f | |
2818 | /* Skip over inter-block insns occurring after BB which are typically | |
2819 | associated with BB (e.g., barriers). If there are any such insns, | |
2820 | we return the last one. Otherwise, we return the end of BB. */ | |
2821 | ||
2822 | static rtx | |
2823 | skip_insns_after_block (basic_block bb) | |
2824 | { | |
2825 | rtx insn, last_insn, next_head, prev; | |
2826 | ||
2827 | next_head = NULL_RTX; | |
2828 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
2829 | next_head = BB_HEAD (bb->next_bb); | |
2830 | ||
2831 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
2832 | { | |
2833 | if (insn == next_head) | |
2834 | break; | |
2835 | ||
2836 | switch (GET_CODE (insn)) | |
2837 | { | |
2838 | case BARRIER: | |
2839 | last_insn = insn; | |
2840 | continue; | |
2841 | ||
2842 | case NOTE: | |
2843 | switch (NOTE_KIND (insn)) | |
2844 | { | |
2845 | case NOTE_INSN_BLOCK_END: | |
2846 | gcc_unreachable (); | |
2847 | continue; | |
2848 | default: | |
2849 | continue; | |
2850 | break; | |
2851 | } | |
2852 | break; | |
2853 | ||
2854 | case CODE_LABEL: | |
2855 | if (NEXT_INSN (insn) | |
2856 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
2857 | { | |
2858 | insn = NEXT_INSN (insn); | |
2859 | last_insn = insn; | |
2860 | continue; | |
2861 | } | |
2862 | break; | |
2863 | ||
2864 | default: | |
2865 | break; | |
2866 | } | |
2867 | ||
2868 | break; | |
2869 | } | |
2870 | ||
2871 | /* It is possible to hit contradictory sequence. For instance: | |
2872 | ||
2873 | jump_insn | |
2874 | NOTE_INSN_BLOCK_BEG | |
2875 | barrier | |
2876 | ||
2877 | Where barrier belongs to jump_insn, but the note does not. This can be | |
2878 | created by removing the basic block originally following | |
2879 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
2880 | ||
2881 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
2882 | { | |
2883 | prev = PREV_INSN (insn); | |
2884 | if (NOTE_P (insn)) | |
2885 | switch (NOTE_KIND (insn)) | |
2886 | { | |
2887 | case NOTE_INSN_BLOCK_END: | |
2888 | gcc_unreachable (); | |
2889 | break; | |
2890 | case NOTE_INSN_DELETED: | |
2891 | case NOTE_INSN_DELETED_LABEL: | |
2892 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
2893 | continue; | |
2894 | default: | |
2895 | reorder_insns (insn, insn, last_insn); | |
2896 | } | |
2897 | } | |
2898 | ||
2899 | return last_insn; | |
2900 | } | |
2901 | ||
2902 | /* Locate or create a label for a given basic block. */ | |
2903 | ||
2904 | static rtx | |
2905 | label_for_bb (basic_block bb) | |
2906 | { | |
2907 | rtx label = BB_HEAD (bb); | |
2908 | ||
2909 | if (!LABEL_P (label)) | |
2910 | { | |
2911 | if (dump_file) | |
2912 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
2913 | ||
2914 | label = block_label (bb); | |
2915 | } | |
2916 | ||
2917 | return label; | |
2918 | } | |
2919 | ||
2920 | /* Locate the effective beginning and end of the insn chain for each | |
2921 | block, as defined by skip_insns_after_block above. */ | |
2922 | ||
2923 | static void | |
2924 | record_effective_endpoints (void) | |
2925 | { | |
2926 | rtx next_insn; | |
2927 | basic_block bb; | |
2928 | rtx insn; | |
2929 | ||
2930 | for (insn = get_insns (); | |
2931 | insn | |
2932 | && NOTE_P (insn) | |
2933 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
2934 | insn = NEXT_INSN (insn)) | |
2935 | continue; | |
2936 | /* No basic blocks at all? */ | |
2937 | gcc_assert (insn); | |
2938 | ||
2939 | if (PREV_INSN (insn)) | |
2940 | cfg_layout_function_header = | |
2941 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
2942 | else | |
2943 | cfg_layout_function_header = NULL_RTX; | |
2944 | ||
2945 | next_insn = get_insns (); | |
2946 | FOR_EACH_BB (bb) | |
2947 | { | |
2948 | rtx end; | |
2949 | ||
2950 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
2951 | BB_HEADER (bb) = unlink_insn_chain (next_insn, | |
2952 | PREV_INSN (BB_HEAD (bb))); | |
2953 | end = skip_insns_after_block (bb); | |
2954 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
2955 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); | |
2956 | next_insn = NEXT_INSN (BB_END (bb)); | |
2957 | } | |
2958 | ||
2959 | cfg_layout_function_footer = next_insn; | |
2960 | if (cfg_layout_function_footer) | |
2961 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
2962 | } | |
2963 | \f | |
2964 | static unsigned int | |
2965 | into_cfg_layout_mode (void) | |
2966 | { | |
2967 | cfg_layout_initialize (0); | |
2968 | return 0; | |
2969 | } | |
2970 | ||
2971 | static unsigned int | |
2972 | outof_cfg_layout_mode (void) | |
2973 | { | |
2974 | basic_block bb; | |
2975 | ||
2976 | FOR_EACH_BB (bb) | |
2977 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
2978 | bb->aux = bb->next_bb; | |
2979 | ||
2980 | cfg_layout_finalize (); | |
2981 | ||
2982 | return 0; | |
2983 | } | |
2984 | ||
2985 | struct rtl_opt_pass pass_into_cfg_layout_mode = | |
2986 | { | |
2987 | { | |
2988 | RTL_PASS, | |
2989 | "into_cfglayout", /* name */ | |
2990 | NULL, /* gate */ | |
2991 | into_cfg_layout_mode, /* execute */ | |
2992 | NULL, /* sub */ | |
2993 | NULL, /* next */ | |
2994 | 0, /* static_pass_number */ | |
2995 | TV_CFG, /* tv_id */ | |
2996 | 0, /* properties_required */ | |
2997 | PROP_cfglayout, /* properties_provided */ | |
2998 | 0, /* properties_destroyed */ | |
2999 | 0, /* todo_flags_start */ | |
3000 | 0 /* todo_flags_finish */ | |
3001 | } | |
3002 | }; | |
3003 | ||
3004 | struct rtl_opt_pass pass_outof_cfg_layout_mode = | |
3005 | { | |
3006 | { | |
3007 | RTL_PASS, | |
3008 | "outof_cfglayout", /* name */ | |
3009 | NULL, /* gate */ | |
3010 | outof_cfg_layout_mode, /* execute */ | |
3011 | NULL, /* sub */ | |
3012 | NULL, /* next */ | |
3013 | 0, /* static_pass_number */ | |
3014 | TV_CFG, /* tv_id */ | |
3015 | 0, /* properties_required */ | |
3016 | 0, /* properties_provided */ | |
3017 | PROP_cfglayout, /* properties_destroyed */ | |
3018 | 0, /* todo_flags_start */ | |
3019 | 0 /* todo_flags_finish */ | |
3020 | } | |
3021 | }; | |
3022 | \f | |
3023 | ||
3024 | /* Link the basic blocks in the correct order, compacting the basic | |
3025 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3026 | function also clears the basic block header and footer fields. | |
3027 | ||
3028 | This function is usually called after a pass (e.g. tracer) finishes | |
3029 | some transformations while in cfglayout mode. The required sequence | |
3030 | of the basic blocks is in a linked list along the bb->aux field. | |
3031 | This functions re-links the basic block prev_bb and next_bb pointers | |
532aafad SB |
3032 | accordingly, and it compacts and renumbers the blocks. |
3033 | ||
3034 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3035 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3036 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3037 | chain. It could do that (to give better initial RTL) if this function | |
3038 | is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */ | |
78bde837 SB |
3039 | |
3040 | void | |
3041 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3042 | { | |
3043 | basic_block bb, prev_bb; | |
3044 | int index; | |
3045 | ||
3046 | /* Maybe dump the re-ordered sequence. */ | |
3047 | if (dump_file) | |
3048 | { | |
3049 | fprintf (dump_file, "Reordered sequence:\n"); | |
3050 | for (bb = ENTRY_BLOCK_PTR->next_bb, index = NUM_FIXED_BLOCKS; | |
3051 | bb; | |
3052 | bb = (basic_block) bb->aux, index++) | |
3053 | { | |
3054 | fprintf (dump_file, " %i ", index); | |
3055 | if (get_bb_original (bb)) | |
3056 | fprintf (dump_file, "duplicate of %i ", | |
3057 | get_bb_original (bb)->index); | |
3058 | else if (forwarder_block_p (bb) | |
3059 | && !LABEL_P (BB_HEAD (bb))) | |
3060 | fprintf (dump_file, "compensation "); | |
3061 | else | |
3062 | fprintf (dump_file, "bb %i ", bb->index); | |
3063 | fprintf (dump_file, " [%i]\n", bb->frequency); | |
3064 | } | |
3065 | } | |
3066 | ||
3067 | /* Now reorder the blocks. */ | |
3068 | prev_bb = ENTRY_BLOCK_PTR; | |
3069 | bb = ENTRY_BLOCK_PTR->next_bb; | |
3070 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) | |
3071 | { | |
3072 | bb->prev_bb = prev_bb; | |
3073 | prev_bb->next_bb = bb; | |
3074 | } | |
3075 | prev_bb->next_bb = EXIT_BLOCK_PTR; | |
3076 | EXIT_BLOCK_PTR->prev_bb = prev_bb; | |
3077 | ||
3078 | /* Then, clean up the aux fields. */ | |
3079 | FOR_ALL_BB (bb) | |
3080 | { | |
3081 | bb->aux = NULL; | |
3082 | if (!stay_in_cfglayout_mode) | |
3083 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; | |
3084 | } | |
3085 | ||
3086 | /* Maybe reset the original copy tables, they are not valid anymore | |
3087 | when we renumber the basic blocks in compact_blocks. If we are | |
3088 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
3089 | free_original_copy_tables (); | |
3090 | if (stay_in_cfglayout_mode) | |
3091 | initialize_original_copy_tables (); | |
3092 | ||
3093 | /* Finally, put basic_block_info in the new order. */ | |
3094 | compact_blocks (); | |
3095 | } | |
3096 | \f | |
3097 | ||
3098 | /* Given a reorder chain, rearrange the code to match. */ | |
3099 | ||
3100 | static void | |
3101 | fixup_reorder_chain (void) | |
3102 | { | |
3103 | basic_block bb; | |
3104 | rtx insn = NULL; | |
3105 | ||
3106 | if (cfg_layout_function_header) | |
3107 | { | |
3108 | set_first_insn (cfg_layout_function_header); | |
3109 | insn = cfg_layout_function_header; | |
3110 | while (NEXT_INSN (insn)) | |
3111 | insn = NEXT_INSN (insn); | |
3112 | } | |
3113 | ||
3114 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3115 | the needed changes to jumps and labels. */ | |
3116 | ||
3117 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb; bb = (basic_block) bb->aux) | |
3118 | { | |
3119 | if (BB_HEADER (bb)) | |
3120 | { | |
3121 | if (insn) | |
3122 | NEXT_INSN (insn) = BB_HEADER (bb); | |
3123 | else | |
3124 | set_first_insn (BB_HEADER (bb)); | |
3125 | PREV_INSN (BB_HEADER (bb)) = insn; | |
3126 | insn = BB_HEADER (bb); | |
3127 | while (NEXT_INSN (insn)) | |
3128 | insn = NEXT_INSN (insn); | |
3129 | } | |
3130 | if (insn) | |
3131 | NEXT_INSN (insn) = BB_HEAD (bb); | |
3132 | else | |
3133 | set_first_insn (BB_HEAD (bb)); | |
3134 | PREV_INSN (BB_HEAD (bb)) = insn; | |
3135 | insn = BB_END (bb); | |
3136 | if (BB_FOOTER (bb)) | |
3137 | { | |
3138 | NEXT_INSN (insn) = BB_FOOTER (bb); | |
3139 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
3140 | while (NEXT_INSN (insn)) | |
3141 | insn = NEXT_INSN (insn); | |
3142 | } | |
3143 | } | |
3144 | ||
3145 | NEXT_INSN (insn) = cfg_layout_function_footer; | |
3146 | if (cfg_layout_function_footer) | |
3147 | PREV_INSN (cfg_layout_function_footer) = insn; | |
3148 | ||
3149 | while (NEXT_INSN (insn)) | |
3150 | insn = NEXT_INSN (insn); | |
3151 | ||
3152 | set_last_insn (insn); | |
3153 | #ifdef ENABLE_CHECKING | |
3154 | verify_insn_chain (); | |
3155 | #endif | |
3156 | ||
3157 | /* Now add jumps and labels as needed to match the blocks new | |
3158 | outgoing edges. */ | |
3159 | ||
3160 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb ; bb = (basic_block) bb->aux) | |
3161 | { | |
3162 | edge e_fall, e_taken, e; | |
3163 | rtx bb_end_insn; | |
3164 | rtx ret_label = NULL_RTX; | |
3165 | basic_block nb, src_bb; | |
3166 | edge_iterator ei; | |
3167 | ||
3168 | if (EDGE_COUNT (bb->succs) == 0) | |
3169 | continue; | |
3170 | ||
3171 | /* Find the old fallthru edge, and another non-EH edge for | |
3172 | a taken jump. */ | |
3173 | e_taken = e_fall = NULL; | |
3174 | ||
3175 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3176 | if (e->flags & EDGE_FALLTHRU) | |
3177 | e_fall = e; | |
3178 | else if (! (e->flags & EDGE_EH)) | |
3179 | e_taken = e; | |
3180 | ||
3181 | bb_end_insn = BB_END (bb); | |
3182 | if (JUMP_P (bb_end_insn)) | |
3183 | { | |
3184 | ret_label = JUMP_LABEL (bb_end_insn); | |
3185 | if (any_condjump_p (bb_end_insn)) | |
3186 | { | |
3187 | /* This might happen if the conditional jump has side | |
3188 | effects and could therefore not be optimized away. | |
3189 | Make the basic block to end with a barrier in order | |
3190 | to prevent rtl_verify_flow_info from complaining. */ | |
3191 | if (!e_fall) | |
3192 | { | |
3193 | gcc_assert (!onlyjump_p (bb_end_insn) | |
3194 | || returnjump_p (bb_end_insn)); | |
3195 | BB_FOOTER (bb) = emit_barrier_after (bb_end_insn); | |
3196 | continue; | |
3197 | } | |
3198 | ||
3199 | /* If the old fallthru is still next, nothing to do. */ | |
3200 | if (bb->aux == e_fall->dest | |
3201 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3202 | continue; | |
3203 | ||
3204 | /* The degenerated case of conditional jump jumping to the next | |
3205 | instruction can happen for jumps with side effects. We need | |
3206 | to construct a forwarder block and this will be done just | |
3207 | fine by force_nonfallthru below. */ | |
3208 | if (!e_taken) | |
3209 | ; | |
3210 | ||
3211 | /* There is another special case: if *neither* block is next, | |
3212 | such as happens at the very end of a function, then we'll | |
3213 | need to add a new unconditional jump. Choose the taken | |
3214 | edge based on known or assumed probability. */ | |
3215 | else if (bb->aux != e_taken->dest) | |
3216 | { | |
3217 | rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0); | |
3218 | ||
3219 | if (note | |
3220 | && INTVAL (XEXP (note, 0)) < REG_BR_PROB_BASE / 2 | |
3221 | && invert_jump (bb_end_insn, | |
3222 | (e_fall->dest == EXIT_BLOCK_PTR | |
3223 | ? NULL_RTX | |
3224 | : label_for_bb (e_fall->dest)), 0)) | |
3225 | { | |
3226 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3227 | gcc_checking_assert (could_fall_through | |
3228 | (e_taken->src, e_taken->dest)); | |
3229 | e_taken->flags |= EDGE_FALLTHRU; | |
3230 | update_br_prob_note (bb); | |
3231 | e = e_fall, e_fall = e_taken, e_taken = e; | |
3232 | } | |
3233 | } | |
3234 | ||
3235 | /* If the "jumping" edge is a crossing edge, and the fall | |
3236 | through edge is non-crossing, leave things as they are. */ | |
3237 | else if ((e_taken->flags & EDGE_CROSSING) | |
3238 | && !(e_fall->flags & EDGE_CROSSING)) | |
3239 | continue; | |
3240 | ||
3241 | /* Otherwise we can try to invert the jump. This will | |
3242 | basically never fail, however, keep up the pretense. */ | |
3243 | else if (invert_jump (bb_end_insn, | |
3244 | (e_fall->dest == EXIT_BLOCK_PTR | |
3245 | ? NULL_RTX | |
3246 | : label_for_bb (e_fall->dest)), 0)) | |
3247 | { | |
3248 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3249 | gcc_checking_assert (could_fall_through | |
3250 | (e_taken->src, e_taken->dest)); | |
3251 | e_taken->flags |= EDGE_FALLTHRU; | |
3252 | update_br_prob_note (bb); | |
3253 | if (LABEL_NUSES (ret_label) == 0 | |
3254 | && single_pred_p (e_taken->dest)) | |
3255 | delete_insn (ret_label); | |
3256 | continue; | |
3257 | } | |
3258 | } | |
3259 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
3260 | { | |
3261 | /* If the old fallthru is still next or if | |
3262 | asm goto doesn't have a fallthru (e.g. when followed by | |
3263 | __builtin_unreachable ()), nothing to do. */ | |
3264 | if (! e_fall | |
3265 | || bb->aux == e_fall->dest | |
3266 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3267 | continue; | |
3268 | ||
3269 | /* Otherwise we'll have to use the fallthru fixup below. */ | |
3270 | } | |
3271 | else | |
3272 | { | |
3273 | /* Otherwise we have some return, switch or computed | |
3274 | jump. In the 99% case, there should not have been a | |
3275 | fallthru edge. */ | |
3276 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
3277 | continue; | |
3278 | } | |
3279 | } | |
3280 | else | |
3281 | { | |
3282 | /* No fallthru implies a noreturn function with EH edges, or | |
3283 | something similarly bizarre. In any case, we don't need to | |
3284 | do anything. */ | |
3285 | if (! e_fall) | |
3286 | continue; | |
3287 | ||
3288 | /* If the fallthru block is still next, nothing to do. */ | |
3289 | if (bb->aux == e_fall->dest) | |
3290 | continue; | |
3291 | ||
3292 | /* A fallthru to exit block. */ | |
3293 | if (e_fall->dest == EXIT_BLOCK_PTR) | |
3294 | continue; | |
3295 | } | |
3296 | ||
3297 | /* We got here if we need to add a new jump insn. | |
3298 | Note force_nonfallthru can delete E_FALL and thus we have to | |
3299 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
3300 | src_bb = e_fall->src; | |
3301 | nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label); | |
3302 | if (nb) | |
3303 | { | |
3304 | nb->aux = bb->aux; | |
3305 | bb->aux = nb; | |
3306 | /* Don't process this new block. */ | |
3307 | bb = nb; | |
3308 | ||
3309 | /* Make sure new bb is tagged for correct section (same as | |
3310 | fall-thru source, since you cannot fall-thru across | |
3311 | section boundaries). */ | |
3312 | BB_COPY_PARTITION (src_bb, single_pred (bb)); | |
3313 | if (flag_reorder_blocks_and_partition | |
3314 | && targetm_common.have_named_sections | |
3315 | && JUMP_P (BB_END (bb)) | |
3316 | && !any_condjump_p (BB_END (bb)) | |
3317 | && (EDGE_SUCC (bb, 0)->flags & EDGE_CROSSING)) | |
3318 | add_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX); | |
3319 | } | |
3320 | } | |
3321 | ||
3322 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
3323 | ||
3324 | /* Annoying special case - jump around dead jumptables left in the code. */ | |
3325 | FOR_EACH_BB (bb) | |
3326 | { | |
3327 | edge e = find_fallthru_edge (bb->succs); | |
3328 | ||
3329 | if (e && !can_fallthru (e->src, e->dest)) | |
3330 | force_nonfallthru (e); | |
3331 | } | |
3332 | ||
3333 | /* Ensure goto_locus from edges has some instructions with that locus | |
3334 | in RTL. */ | |
3335 | if (!optimize) | |
3336 | FOR_EACH_BB (bb) | |
3337 | { | |
3338 | edge e; | |
3339 | edge_iterator ei; | |
3340 | ||
3341 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2f13f2de | 3342 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5368224f | 3343 | && !(e->flags & EDGE_ABNORMAL)) |
78bde837 SB |
3344 | { |
3345 | edge e2; | |
3346 | edge_iterator ei2; | |
3347 | basic_block dest, nb; | |
3348 | rtx end; | |
3349 | ||
3350 | insn = BB_END (e->src); | |
3351 | end = PREV_INSN (BB_HEAD (e->src)); | |
3352 | while (insn != end | |
5368224f | 3353 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
78bde837 SB |
3354 | insn = PREV_INSN (insn); |
3355 | if (insn != end | |
5368224f | 3356 | && INSN_LOCATION (insn) == e->goto_locus) |
78bde837 SB |
3357 | continue; |
3358 | if (simplejump_p (BB_END (e->src)) | |
5368224f | 3359 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
78bde837 | 3360 | { |
5368224f | 3361 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
78bde837 SB |
3362 | continue; |
3363 | } | |
3364 | dest = e->dest; | |
3365 | if (dest == EXIT_BLOCK_PTR) | |
3366 | { | |
3367 | /* Non-fallthru edges to the exit block cannot be split. */ | |
3368 | if (!(e->flags & EDGE_FALLTHRU)) | |
3369 | continue; | |
3370 | } | |
3371 | else | |
3372 | { | |
3373 | insn = BB_HEAD (dest); | |
3374 | end = NEXT_INSN (BB_END (dest)); | |
3375 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
3376 | insn = NEXT_INSN (insn); | |
5368224f DC |
3377 | if (insn != end && INSN_HAS_LOCATION (insn) |
3378 | && INSN_LOCATION (insn) == e->goto_locus) | |
78bde837 SB |
3379 | continue; |
3380 | } | |
3381 | nb = split_edge (e); | |
3382 | if (!INSN_P (BB_END (nb))) | |
3383 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), | |
3384 | nb); | |
5368224f | 3385 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
78bde837 SB |
3386 | |
3387 | /* If there are other incoming edges to the destination block | |
3388 | with the same goto locus, redirect them to the new block as | |
3389 | well, this can prevent other such blocks from being created | |
3390 | in subsequent iterations of the loop. */ | |
3391 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
2f13f2de | 3392 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
78bde837 | 3393 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5368224f | 3394 | && e->goto_locus == e2->goto_locus) |
78bde837 SB |
3395 | redirect_edge_and_branch (e2, nb); |
3396 | else | |
3397 | ei_next (&ei2); | |
3398 | } | |
3399 | } | |
3400 | } | |
3401 | \f | |
3402 | /* Perform sanity checks on the insn chain. | |
3403 | 1. Check that next/prev pointers are consistent in both the forward and | |
3404 | reverse direction. | |
3405 | 2. Count insns in chain, going both directions, and check if equal. | |
3406 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
3407 | ||
3408 | DEBUG_FUNCTION void | |
3409 | verify_insn_chain (void) | |
3410 | { | |
3411 | rtx x, prevx, nextx; | |
3412 | int insn_cnt1, insn_cnt2; | |
3413 | ||
3414 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
3415 | x != 0; | |
3416 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
3417 | gcc_assert (PREV_INSN (x) == prevx); | |
3418 | ||
3419 | gcc_assert (prevx == get_last_insn ()); | |
3420 | ||
3421 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
3422 | x != 0; | |
3423 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
3424 | gcc_assert (NEXT_INSN (x) == nextx); | |
3425 | ||
3426 | gcc_assert (insn_cnt1 == insn_cnt2); | |
3427 | } | |
3428 | \f | |
3429 | /* If we have assembler epilogues, the block falling through to exit must | |
3430 | be the last one in the reordered chain when we reach final. Ensure | |
3431 | that this condition is met. */ | |
3432 | static void | |
3433 | fixup_fallthru_exit_predecessor (void) | |
3434 | { | |
3435 | edge e; | |
3436 | basic_block bb = NULL; | |
3437 | ||
3438 | /* This transformation is not valid before reload, because we might | |
3439 | separate a call from the instruction that copies the return | |
3440 | value. */ | |
3441 | gcc_assert (reload_completed); | |
3442 | ||
3443 | e = find_fallthru_edge (EXIT_BLOCK_PTR->preds); | |
3444 | if (e) | |
3445 | bb = e->src; | |
3446 | ||
3447 | if (bb && bb->aux) | |
3448 | { | |
3449 | basic_block c = ENTRY_BLOCK_PTR->next_bb; | |
3450 | ||
3451 | /* If the very first block is the one with the fall-through exit | |
3452 | edge, we have to split that block. */ | |
3453 | if (c == bb) | |
3454 | { | |
3455 | bb = split_block (bb, NULL)->dest; | |
3456 | bb->aux = c->aux; | |
3457 | c->aux = bb; | |
3458 | BB_FOOTER (bb) = BB_FOOTER (c); | |
3459 | BB_FOOTER (c) = NULL; | |
3460 | } | |
3461 | ||
3462 | while (c->aux != bb) | |
3463 | c = (basic_block) c->aux; | |
3464 | ||
3465 | c->aux = bb->aux; | |
3466 | while (c->aux) | |
3467 | c = (basic_block) c->aux; | |
3468 | ||
3469 | c->aux = bb; | |
3470 | bb->aux = NULL; | |
3471 | } | |
3472 | } | |
3473 | ||
3474 | /* In case there are more than one fallthru predecessors of exit, force that | |
3475 | there is only one. */ | |
3476 | ||
3477 | static void | |
3478 | force_one_exit_fallthru (void) | |
3479 | { | |
3480 | edge e, predecessor = NULL; | |
3481 | bool more = false; | |
3482 | edge_iterator ei; | |
3483 | basic_block forwarder, bb; | |
3484 | ||
3485 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) | |
3486 | if (e->flags & EDGE_FALLTHRU) | |
3487 | { | |
3488 | if (predecessor == NULL) | |
3489 | predecessor = e; | |
3490 | else | |
3491 | { | |
3492 | more = true; | |
3493 | break; | |
3494 | } | |
3495 | } | |
3496 | ||
3497 | if (!more) | |
3498 | return; | |
3499 | ||
3500 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
3501 | them. */ | |
3502 | forwarder = split_edge (predecessor); | |
3503 | for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); ) | |
3504 | { | |
3505 | if (e->src == forwarder | |
3506 | || !(e->flags & EDGE_FALLTHRU)) | |
3507 | ei_next (&ei); | |
3508 | else | |
3509 | redirect_edge_and_branch_force (e, forwarder); | |
3510 | } | |
3511 | ||
3512 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
3513 | exit block. */ | |
3514 | FOR_EACH_BB (bb) | |
3515 | { | |
3516 | if (bb->aux == NULL && bb != forwarder) | |
3517 | { | |
3518 | bb->aux = forwarder; | |
3519 | break; | |
3520 | } | |
3521 | } | |
3522 | } | |
3523 | \f | |
3524 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
3525 | ||
3526 | static bool | |
3527 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
3528 | { | |
3529 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
3530 | the dispatch table. This is difficult to do, as the instructions | |
3531 | computing jump destination may be hoisted outside the basic block. */ | |
3532 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
3533 | return false; | |
3534 | ||
3535 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
3536 | if (targetm.cannot_copy_insn_p) | |
3537 | { | |
3538 | rtx insn = BB_HEAD (bb); | |
3539 | while (1) | |
3540 | { | |
3541 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
3542 | return false; | |
3543 | if (insn == BB_END (bb)) | |
3544 | break; | |
3545 | insn = NEXT_INSN (insn); | |
3546 | } | |
3547 | } | |
3548 | ||
3549 | return true; | |
3550 | } | |
3551 | ||
3552 | rtx | |
3553 | duplicate_insn_chain (rtx from, rtx to) | |
3554 | { | |
3555 | rtx insn, last, copy; | |
3556 | ||
3557 | /* Avoid updating of boundaries of previous basic block. The | |
3558 | note will get removed from insn stream in fixup. */ | |
3559 | last = emit_note (NOTE_INSN_DELETED); | |
3560 | ||
3561 | /* Create copy at the end of INSN chain. The chain will | |
3562 | be reordered later. */ | |
3563 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
3564 | { | |
3565 | switch (GET_CODE (insn)) | |
3566 | { | |
3567 | case DEBUG_INSN: | |
3568 | /* Don't duplicate label debug insns. */ | |
3569 | if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
3570 | break; | |
3571 | /* FALLTHRU */ | |
3572 | case INSN: | |
3573 | case CALL_INSN: | |
3574 | case JUMP_INSN: | |
3575 | /* Avoid copying of dispatch tables. We never duplicate | |
3576 | tablejumps, so this can hit only in case the table got | |
3577 | moved far from original jump. */ | |
3578 | if (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
3579 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC) | |
3580 | { | |
3581 | /* Avoid copying following barrier as well if any | |
3582 | (and debug insns in between). */ | |
3583 | rtx next; | |
3584 | ||
3585 | for (next = NEXT_INSN (insn); | |
3586 | next != NEXT_INSN (to); | |
3587 | next = NEXT_INSN (next)) | |
3588 | if (!DEBUG_INSN_P (next)) | |
3589 | break; | |
3590 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
3591 | insn = next; | |
3592 | break; | |
3593 | } | |
3594 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); | |
3595 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
3596 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
3597 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
3598 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
3599 | break; | |
3600 | ||
3601 | case CODE_LABEL: | |
3602 | break; | |
3603 | ||
3604 | case BARRIER: | |
3605 | emit_barrier (); | |
3606 | break; | |
3607 | ||
3608 | case NOTE: | |
3609 | switch (NOTE_KIND (insn)) | |
3610 | { | |
3611 | /* In case prologue is empty and function contain label | |
3612 | in first BB, we may want to copy the block. */ | |
3613 | case NOTE_INSN_PROLOGUE_END: | |
3614 | ||
3615 | case NOTE_INSN_DELETED: | |
3616 | case NOTE_INSN_DELETED_LABEL: | |
3617 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3618 | /* No problem to strip these. */ | |
3619 | case NOTE_INSN_FUNCTION_BEG: | |
3620 | /* There is always just single entry to function. */ | |
3621 | case NOTE_INSN_BASIC_BLOCK: | |
3622 | break; | |
3623 | ||
3624 | case NOTE_INSN_EPILOGUE_BEG: | |
3625 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
3626 | emit_note_copy (insn); | |
3627 | break; | |
3628 | ||
3629 | default: | |
3630 | /* All other notes should have already been eliminated. */ | |
3631 | gcc_unreachable (); | |
3632 | } | |
3633 | break; | |
3634 | default: | |
3635 | gcc_unreachable (); | |
3636 | } | |
3637 | } | |
3638 | insn = NEXT_INSN (last); | |
3639 | delete_insn (last); | |
3640 | return insn; | |
3641 | } | |
3642 | ||
3643 | /* Create a duplicate of the basic block BB. */ | |
3644 | ||
3645 | static basic_block | |
3646 | cfg_layout_duplicate_bb (basic_block bb) | |
3647 | { | |
3648 | rtx insn; | |
3649 | basic_block new_bb; | |
3650 | ||
3651 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb)); | |
3652 | new_bb = create_basic_block (insn, | |
3653 | insn ? get_last_insn () : NULL, | |
3654 | EXIT_BLOCK_PTR->prev_bb); | |
3655 | ||
3656 | BB_COPY_PARTITION (new_bb, bb); | |
3657 | if (BB_HEADER (bb)) | |
3658 | { | |
3659 | insn = BB_HEADER (bb); | |
3660 | while (NEXT_INSN (insn)) | |
3661 | insn = NEXT_INSN (insn); | |
3662 | insn = duplicate_insn_chain (BB_HEADER (bb), insn); | |
3663 | if (insn) | |
3664 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3665 | } | |
3666 | ||
3667 | if (BB_FOOTER (bb)) | |
3668 | { | |
3669 | insn = BB_FOOTER (bb); | |
3670 | while (NEXT_INSN (insn)) | |
3671 | insn = NEXT_INSN (insn); | |
3672 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn); | |
3673 | if (insn) | |
3674 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3675 | } | |
3676 | ||
3677 | return new_bb; | |
3678 | } | |
3679 | ||
3680 | \f | |
3681 | /* Main entry point to this module - initialize the datastructures for | |
3682 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
3683 | ||
3684 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
3685 | ||
3686 | void | |
3687 | cfg_layout_initialize (unsigned int flags) | |
3688 | { | |
3689 | rtx x; | |
3690 | basic_block bb; | |
3691 | ||
3692 | initialize_original_copy_tables (); | |
3693 | ||
3694 | cfg_layout_rtl_register_cfg_hooks (); | |
3695 | ||
3696 | record_effective_endpoints (); | |
3697 | ||
3698 | /* Make sure that the targets of non local gotos are marked. */ | |
3699 | for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1)) | |
3700 | { | |
3701 | bb = BLOCK_FOR_INSN (XEXP (x, 0)); | |
3702 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; | |
3703 | } | |
3704 | ||
3705 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
3706 | } | |
3707 | ||
3708 | /* Splits superblocks. */ | |
3709 | void | |
3710 | break_superblocks (void) | |
3711 | { | |
3712 | sbitmap superblocks; | |
3713 | bool need = false; | |
3714 | basic_block bb; | |
3715 | ||
3716 | superblocks = sbitmap_alloc (last_basic_block); | |
3717 | sbitmap_zero (superblocks); | |
3718 | ||
3719 | FOR_EACH_BB (bb) | |
3720 | if (bb->flags & BB_SUPERBLOCK) | |
3721 | { | |
3722 | bb->flags &= ~BB_SUPERBLOCK; | |
3723 | SET_BIT (superblocks, bb->index); | |
3724 | need = true; | |
3725 | } | |
3726 | ||
3727 | if (need) | |
3728 | { | |
3729 | rebuild_jump_labels (get_insns ()); | |
3730 | find_many_sub_basic_blocks (superblocks); | |
3731 | } | |
3732 | ||
3733 | free (superblocks); | |
3734 | } | |
3735 | ||
3736 | /* Finalize the changes: reorder insn list according to the sequence specified | |
3737 | by aux pointers, enter compensation code, rebuild scope forest. */ | |
3738 | ||
3739 | void | |
3740 | cfg_layout_finalize (void) | |
3741 | { | |
3742 | #ifdef ENABLE_CHECKING | |
3743 | verify_flow_info (); | |
3744 | #endif | |
3745 | force_one_exit_fallthru (); | |
3746 | rtl_register_cfg_hooks (); | |
3747 | if (reload_completed | |
3748 | #ifdef HAVE_epilogue | |
3749 | && !HAVE_epilogue | |
3750 | #endif | |
3751 | ) | |
3752 | fixup_fallthru_exit_predecessor (); | |
3753 | fixup_reorder_chain (); | |
3754 | ||
3755 | rebuild_jump_labels (get_insns ()); | |
3756 | delete_dead_jumptables (); | |
3757 | ||
3758 | #ifdef ENABLE_CHECKING | |
3759 | verify_insn_chain (); | |
3760 | verify_flow_info (); | |
3761 | #endif | |
3762 | } | |
3763 | ||
ba5e9aca | 3764 | |
9ee634e3 | 3765 | /* Same as split_block but update cfg_layout structures. */ |
f470c378 ZD |
3766 | |
3767 | static basic_block | |
d329e058 | 3768 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 | 3769 | { |
ae50c0cb | 3770 | rtx insn = (rtx) insnp; |
f470c378 | 3771 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 3772 | |
bcc708fc MM |
3773 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
3774 | BB_FOOTER (bb) = NULL; | |
9ee634e3 | 3775 | |
f470c378 | 3776 | return new_bb; |
9ee634e3 JH |
3777 | } |
3778 | ||
9ee634e3 | 3779 | /* Redirect Edge to DEST. */ |
6de9cd9a | 3780 | static edge |
d329e058 | 3781 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
3782 | { |
3783 | basic_block src = e->src; | |
6de9cd9a | 3784 | edge ret; |
9ee634e3 | 3785 | |
bc35512f | 3786 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 3787 | return NULL; |
bc35512f | 3788 | |
3348b696 | 3789 | if (e->dest == dest) |
6de9cd9a | 3790 | return e; |
bc35512f | 3791 | |
3348b696 | 3792 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a | 3793 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a | 3794 | { |
6fb5fa3c | 3795 | df_set_bb_dirty (src); |
6de9cd9a | 3796 | return ret; |
f345f21a | 3797 | } |
bc35512f JH |
3798 | |
3799 | if (e->src == ENTRY_BLOCK_PTR | |
3800 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) | |
3801 | { | |
c263766c RH |
3802 | if (dump_file) |
3803 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
3804 | e->src->index, dest->index); |
3805 | ||
6fb5fa3c | 3806 | df_set_bb_dirty (e->src); |
bc35512f | 3807 | redirect_edge_succ (e, dest); |
6de9cd9a | 3808 | return e; |
bc35512f JH |
3809 | } |
3810 | ||
9ee634e3 JH |
3811 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
3812 | in the case the basic block appears to be in sequence. Avoid this | |
3813 | transformation. */ | |
3814 | ||
9ee634e3 JH |
3815 | if (e->flags & EDGE_FALLTHRU) |
3816 | { | |
3817 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 3818 | if (JUMP_P (BB_END (src)) |
432f982f JH |
3819 | && label_is_jump_target_p (BB_HEAD (e->dest), |
3820 | BB_END (src))) | |
9ee634e3 | 3821 | { |
341c100f | 3822 | edge redirected; |
c22cacf3 | 3823 | |
c263766c RH |
3824 | if (dump_file) |
3825 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
3826 | "%i->%i redirected to %i\n", |
3827 | e->src->index, e->dest->index, dest->index); | |
3828 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
3829 | redirected = redirect_branch_edge (e, dest); |
3830 | gcc_assert (redirected); | |
0c617be4 JL |
3831 | redirected->flags |= EDGE_FALLTHRU; |
3832 | df_set_bb_dirty (redirected->src); | |
3833 | return redirected; | |
9ee634e3 JH |
3834 | } |
3835 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 3836 | of conditional jump, remove it. */ |
628f6a4e | 3837 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 3838 | { |
03101c6f KH |
3839 | /* Find the edge that is different from E. */ |
3840 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 3841 | |
9ee634e3 | 3842 | if (s->dest == dest |
a813c111 SB |
3843 | && any_condjump_p (BB_END (src)) |
3844 | && onlyjump_p (BB_END (src))) | |
3845 | delete_insn (BB_END (src)); | |
9ee634e3 | 3846 | } |
c263766c | 3847 | if (dump_file) |
dc764d10 | 3848 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
bc35512f | 3849 | e->src->index, e->dest->index, dest->index); |
0c617be4 | 3850 | ret = redirect_edge_succ_nodup (e, dest); |
9ee634e3 JH |
3851 | } |
3852 | else | |
bc35512f | 3853 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
3854 | |
3855 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
341c100f | 3856 | gcc_assert (!simplejump_p (BB_END (src))); |
9ee634e3 | 3857 | |
6fb5fa3c | 3858 | df_set_bb_dirty (src); |
9ee634e3 JH |
3859 | return ret; |
3860 | } | |
3861 | ||
3862 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
3863 | static basic_block | |
d329e058 | 3864 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 3865 | { |
341c100f NS |
3866 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
3867 | ||
3868 | gcc_assert (redirected); | |
9ee634e3 JH |
3869 | return NULL; |
3870 | } | |
3871 | ||
f470c378 ZD |
3872 | /* Same as delete_basic_block but update cfg_layout structures. */ |
3873 | ||
9ee634e3 | 3874 | static void |
d329e058 | 3875 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 3876 | { |
a813c111 | 3877 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 3878 | |
bcc708fc | 3879 | if (BB_HEADER (bb)) |
9ee634e3 | 3880 | { |
a813c111 | 3881 | next = BB_HEAD (bb); |
9ee634e3 | 3882 | if (prev) |
bcc708fc | 3883 | NEXT_INSN (prev) = BB_HEADER (bb); |
9ee634e3 | 3884 | else |
bcc708fc MM |
3885 | set_first_insn (BB_HEADER (bb)); |
3886 | PREV_INSN (BB_HEADER (bb)) = prev; | |
3887 | insn = BB_HEADER (bb); | |
9ee634e3 JH |
3888 | while (NEXT_INSN (insn)) |
3889 | insn = NEXT_INSN (insn); | |
3890 | NEXT_INSN (insn) = next; | |
3891 | PREV_INSN (next) = insn; | |
3892 | } | |
a813c111 | 3893 | next = NEXT_INSN (BB_END (bb)); |
bcc708fc | 3894 | if (BB_FOOTER (bb)) |
9ee634e3 | 3895 | { |
bcc708fc | 3896 | insn = BB_FOOTER (bb); |
bc35512f JH |
3897 | while (insn) |
3898 | { | |
4b4bf941 | 3899 | if (BARRIER_P (insn)) |
bc35512f JH |
3900 | { |
3901 | if (PREV_INSN (insn)) | |
3902 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
3903 | else | |
bcc708fc | 3904 | BB_FOOTER (bb) = NEXT_INSN (insn); |
bc35512f JH |
3905 | if (NEXT_INSN (insn)) |
3906 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
3907 | } | |
4b4bf941 | 3908 | if (LABEL_P (insn)) |
bc35512f JH |
3909 | break; |
3910 | insn = NEXT_INSN (insn); | |
3911 | } | |
bcc708fc | 3912 | if (BB_FOOTER (bb)) |
bc35512f | 3913 | { |
a813c111 | 3914 | insn = BB_END (bb); |
bcc708fc MM |
3915 | NEXT_INSN (insn) = BB_FOOTER (bb); |
3916 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
bc35512f JH |
3917 | while (NEXT_INSN (insn)) |
3918 | insn = NEXT_INSN (insn); | |
3919 | NEXT_INSN (insn) = next; | |
3920 | if (next) | |
3921 | PREV_INSN (next) = insn; | |
3922 | else | |
3923 | set_last_insn (insn); | |
3924 | } | |
9ee634e3 JH |
3925 | } |
3926 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
bcc708fc | 3927 | to = &BB_HEADER (bb->next_bb); |
9ee634e3 JH |
3928 | else |
3929 | to = &cfg_layout_function_footer; | |
997de8ed | 3930 | |
9ee634e3 JH |
3931 | rtl_delete_block (bb); |
3932 | ||
3933 | if (prev) | |
3934 | prev = NEXT_INSN (prev); | |
d329e058 | 3935 | else |
9ee634e3 JH |
3936 | prev = get_insns (); |
3937 | if (next) | |
3938 | next = PREV_INSN (next); | |
d329e058 | 3939 | else |
9ee634e3 JH |
3940 | next = get_last_insn (); |
3941 | ||
3942 | if (next && NEXT_INSN (next) != prev) | |
3943 | { | |
3944 | remaints = unlink_insn_chain (prev, next); | |
3945 | insn = remaints; | |
3946 | while (NEXT_INSN (insn)) | |
3947 | insn = NEXT_INSN (insn); | |
3948 | NEXT_INSN (insn) = *to; | |
3949 | if (*to) | |
3950 | PREV_INSN (*to) = insn; | |
3951 | *to = remaints; | |
3952 | } | |
3953 | } | |
3954 | ||
beb235f8 | 3955 | /* Return true when blocks A and B can be safely merged. */ |
b48d0358 | 3956 | |
bc35512f | 3957 | static bool |
b48d0358 | 3958 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
bc35512f | 3959 | { |
750054a2 CT |
3960 | /* If we are partitioning hot/cold basic blocks, we don't want to |
3961 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
3962 | and cold sections. |
3963 | ||
8e8d5162 | 3964 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
3965 | be optimizable (or blocks that appear to be mergeable), but which really |
3966 | must be left untouched (they are required to make it safely across | |
3967 | partition boundaries). See the comments at the top of | |
8e8d5162 CT |
3968 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
3969 | ||
87c8b4be | 3970 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 3971 | return false; |
750054a2 | 3972 | |
7d776ee2 RG |
3973 | /* Protect the loop latches. */ |
3974 | if (current_loops && b->loop_father->latch == b) | |
3975 | return false; | |
3976 | ||
894a84b5 BS |
3977 | /* If we would end up moving B's instructions, make sure it doesn't fall |
3978 | through into the exit block, since we cannot recover from a fallthrough | |
3979 | edge into the exit block occurring in the middle of a function. */ | |
3980 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
3981 | { | |
3982 | edge e = find_fallthru_edge (b->succs); | |
3983 | if (e && e->dest == EXIT_BLOCK_PTR) | |
3984 | return false; | |
3985 | } | |
3986 | ||
bc35512f | 3987 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
3988 | return (single_succ_p (a) |
3989 | && single_succ (a) == b | |
3990 | && single_pred_p (b) == 1 | |
628f6a4e | 3991 | && a != b |
bc35512f | 3992 | /* Must be simple edge. */ |
c5cbcccf | 3993 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f | 3994 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR |
49ea3702 SB |
3995 | /* If the jump insn has side effects, we can't kill the edge. |
3996 | When not optimizing, try_redirect_by_replacing_jump will | |
3997 | not allow us to redirect an edge by replacing a table jump. */ | |
4b4bf941 | 3998 | && (!JUMP_P (BB_END (a)) |
49ea3702 | 3999 | || ((!optimize || reload_completed) |
a813c111 | 4000 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
4001 | } |
4002 | ||
41806d92 NS |
4003 | /* Merge block A and B. The blocks must be mergeable. */ |
4004 | ||
bc35512f JH |
4005 | static void |
4006 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4007 | { | |
50a36e42 | 4008 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
f9df6f16 | 4009 | rtx insn; |
50a36e42 | 4010 | |
77a74ed7 | 4011 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f | 4012 | |
6fb5fa3c | 4013 | if (dump_file) |
50a36e42 EB |
4014 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4015 | a->index); | |
6fb5fa3c | 4016 | |
bc35512f | 4017 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 4018 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 | 4019 | { |
2c97f8e4 RH |
4020 | delete_insn (BB_HEAD (b)); |
4021 | } | |
bc35512f JH |
4022 | |
4023 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4024 | it cleaned up. */ | |
4b4bf941 | 4025 | if (JUMP_P (BB_END (a))) |
628f6a4e | 4026 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 4027 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f | 4028 | |
9be94227 | 4029 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
7241571e | 4030 | some unique locus, emit a nop with that locus in between. */ |
9be94227 EB |
4031 | if (!optimize) |
4032 | emit_nop_for_unique_locus_between (a, b); | |
7241571e | 4033 | |
bc35512f | 4034 | /* Possible line number notes should appear in between. */ |
bcc708fc | 4035 | if (BB_HEADER (b)) |
bc35512f | 4036 | { |
a813c111 | 4037 | rtx first = BB_END (a), last; |
bc35512f | 4038 | |
bcc708fc | 4039 | last = emit_insn_after_noloc (BB_HEADER (b), BB_END (a), a); |
bd73623c JJ |
4040 | /* The above might add a BARRIER as BB_END, but as barriers |
4041 | aren't valid parts of a bb, remove_insn doesn't update | |
4042 | BB_END if it is a barrier. So adjust BB_END here. */ | |
4043 | while (BB_END (a) != first && BARRIER_P (BB_END (a))) | |
4044 | BB_END (a) = PREV_INSN (BB_END (a)); | |
a7b87f73 | 4045 | delete_insn_chain (NEXT_INSN (first), last, false); |
bcc708fc | 4046 | BB_HEADER (b) = NULL; |
bc35512f JH |
4047 | } |
4048 | ||
4049 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 4050 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 4051 | { |
f9df6f16 | 4052 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
6c3d0e31 | 4053 | |
f9df6f16 | 4054 | emit_insn_after_noloc (insn, BB_END (a), a); |
bc35512f JH |
4055 | } |
4056 | /* Otherwise just re-associate the instructions. */ | |
4057 | else | |
4058 | { | |
a813c111 | 4059 | insn = BB_HEAD (b); |
a813c111 | 4060 | BB_END (a) = BB_END (b); |
bc35512f JH |
4061 | } |
4062 | ||
f9df6f16 JJ |
4063 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4064 | We need to explicitly call. */ | |
4065 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4066 | ||
4067 | /* Skip possible DELETED_LABEL insn. */ | |
4068 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4069 | insn = NEXT_INSN (insn); | |
4070 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
4071 | BB_HEAD (b) = NULL; | |
4072 | delete_insn (insn); | |
4073 | ||
6fb5fa3c DB |
4074 | df_bb_delete (b->index); |
4075 | ||
bc35512f | 4076 | /* Possible tablejumps and barriers should appear after the block. */ |
bcc708fc | 4077 | if (BB_FOOTER (b)) |
bc35512f | 4078 | { |
bcc708fc MM |
4079 | if (!BB_FOOTER (a)) |
4080 | BB_FOOTER (a) = BB_FOOTER (b); | |
bc35512f JH |
4081 | else |
4082 | { | |
bcc708fc | 4083 | rtx last = BB_FOOTER (a); |
bc35512f JH |
4084 | |
4085 | while (NEXT_INSN (last)) | |
4086 | last = NEXT_INSN (last); | |
bcc708fc MM |
4087 | NEXT_INSN (last) = BB_FOOTER (b); |
4088 | PREV_INSN (BB_FOOTER (b)) = last; | |
bc35512f | 4089 | } |
bcc708fc | 4090 | BB_FOOTER (b) = NULL; |
bc35512f JH |
4091 | } |
4092 | ||
50a36e42 | 4093 | /* If B was a forwarder block, propagate the locus on the edge. */ |
2f13f2de DC |
4094 | if (forwarder_p |
4095 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) != UNKNOWN_LOCATION) | |
50a36e42 EB |
4096 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4097 | ||
c263766c | 4098 | if (dump_file) |
50a36e42 | 4099 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
bc35512f JH |
4100 | } |
4101 | ||
4102 | /* Split edge E. */ | |
f470c378 | 4103 | |
bc35512f JH |
4104 | static basic_block |
4105 | cfg_layout_split_edge (edge e) | |
4106 | { | |
bc35512f JH |
4107 | basic_block new_bb = |
4108 | create_basic_block (e->src != ENTRY_BLOCK_PTR | |
a813c111 | 4109 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
4110 | NULL_RTX, e->src); |
4111 | ||
3e7eb734 JJ |
4112 | if (e->dest == EXIT_BLOCK_PTR) |
4113 | BB_COPY_PARTITION (new_bb, e->src); | |
4114 | else | |
4115 | BB_COPY_PARTITION (new_bb, e->dest); | |
a9b2ee88 | 4116 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
4117 | redirect_edge_and_branch_force (e, new_bb); |
4118 | ||
4119 | return new_bb; | |
4120 | } | |
4121 | ||
f470c378 ZD |
4122 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
4123 | ||
4124 | static void | |
4125 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
4126 | { | |
4127 | } | |
4128 | ||
df92c640 SB |
4129 | /* Return true if BB contains only labels or non-executable |
4130 | instructions. */ | |
4131 | ||
4132 | static bool | |
4133 | rtl_block_empty_p (basic_block bb) | |
4134 | { | |
4135 | rtx insn; | |
4136 | ||
4137 | if (bb == ENTRY_BLOCK_PTR || bb == EXIT_BLOCK_PTR) | |
4138 | return true; | |
4139 | ||
4140 | FOR_BB_INSNS (bb, insn) | |
4141 | if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn)) | |
4142 | return false; | |
4143 | ||
4144 | return true; | |
4145 | } | |
4146 | ||
4147 | /* Split a basic block if it ends with a conditional branch and if | |
4148 | the other part of the block is not empty. */ | |
4149 | ||
4150 | static basic_block | |
4151 | rtl_split_block_before_cond_jump (basic_block bb) | |
4152 | { | |
4153 | rtx insn; | |
4154 | rtx split_point = NULL; | |
4155 | rtx last = NULL; | |
4156 | bool found_code = false; | |
4157 | ||
4158 | FOR_BB_INSNS (bb, insn) | |
4159 | { | |
4160 | if (any_condjump_p (insn)) | |
4161 | split_point = last; | |
4162 | else if (NONDEBUG_INSN_P (insn)) | |
4163 | found_code = true; | |
4164 | last = insn; | |
4165 | } | |
4166 | ||
4167 | /* Did not find everything. */ | |
4168 | if (found_code && split_point) | |
4169 | return split_block (bb, split_point)->dest; | |
4170 | else | |
4171 | return NULL; | |
4172 | } | |
4173 | ||
6de9cd9a DN |
4174 | /* Return 1 if BB ends with a call, possibly followed by some |
4175 | instructions that must stay with the call, 0 otherwise. */ | |
4176 | ||
4177 | static bool | |
b48d0358 | 4178 | rtl_block_ends_with_call_p (basic_block bb) |
6de9cd9a DN |
4179 | { |
4180 | rtx insn = BB_END (bb); | |
4181 | ||
4b4bf941 | 4182 | while (!CALL_P (insn) |
6de9cd9a | 4183 | && insn != BB_HEAD (bb) |
92ddef69 | 4184 | && (keep_with_call_p (insn) |
b5b8b0ac AO |
4185 | || NOTE_P (insn) |
4186 | || DEBUG_INSN_P (insn))) | |
6de9cd9a | 4187 | insn = PREV_INSN (insn); |
4b4bf941 | 4188 | return (CALL_P (insn)); |
6de9cd9a DN |
4189 | } |
4190 | ||
4191 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
4192 | ||
4193 | static bool | |
9678086d | 4194 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
6de9cd9a DN |
4195 | { |
4196 | return any_condjump_p (BB_END (bb)); | |
4197 | } | |
4198 | ||
4199 | /* Return true if we need to add fake edge to exit. | |
4200 | Helper function for rtl_flow_call_edges_add. */ | |
4201 | ||
4202 | static bool | |
9678086d | 4203 | need_fake_edge_p (const_rtx insn) |
6de9cd9a DN |
4204 | { |
4205 | if (!INSN_P (insn)) | |
4206 | return false; | |
4207 | ||
4b4bf941 | 4208 | if ((CALL_P (insn) |
6de9cd9a DN |
4209 | && !SIBLING_CALL_P (insn) |
4210 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
becfd6e5 | 4211 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
6de9cd9a DN |
4212 | return true; |
4213 | ||
4214 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
4215 | && MEM_VOLATILE_P (PATTERN (insn))) | |
4216 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
4217 | && asm_noperands (insn) != -1 | |
4218 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
4219 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
4220 | } | |
4221 | ||
4222 | /* Add fake edges to the function exit for any non constant and non noreturn | |
4223 | calls, volatile inline assembly in the bitmap of blocks specified by | |
4224 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
4225 | that were split. | |
4226 | ||
4227 | The goal is to expose cases in which entering a basic block does not imply | |
4228 | that all subsequent instructions must be executed. */ | |
4229 | ||
4230 | static int | |
4231 | rtl_flow_call_edges_add (sbitmap blocks) | |
4232 | { | |
4233 | int i; | |
4234 | int blocks_split = 0; | |
4235 | int last_bb = last_basic_block; | |
4236 | bool check_last_block = false; | |
4237 | ||
24bd1a0b | 4238 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
4239 | return 0; |
4240 | ||
4241 | if (! blocks) | |
4242 | check_last_block = true; | |
4243 | else | |
4244 | check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index); | |
4245 | ||
4246 | /* In the last basic block, before epilogue generation, there will be | |
4247 | a fallthru edge to EXIT. Special care is required if the last insn | |
4248 | of the last basic block is a call because make_edge folds duplicate | |
4249 | edges, which would result in the fallthru edge also being marked | |
4250 | fake, which would result in the fallthru edge being removed by | |
4251 | remove_fake_edges, which would result in an invalid CFG. | |
4252 | ||
4253 | Moreover, we can't elide the outgoing fake edge, since the block | |
4254 | profiler needs to take this into account in order to solve the minimal | |
4255 | spanning tree in the case that the call doesn't return. | |
4256 | ||
4257 | Handle this by adding a dummy instruction in a new last basic block. */ | |
4258 | if (check_last_block) | |
4259 | { | |
4260 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
4261 | rtx insn = BB_END (bb); | |
4262 | ||
4263 | /* Back up past insns that must be kept in the same block as a call. */ | |
4264 | while (insn != BB_HEAD (bb) | |
4265 | && keep_with_call_p (insn)) | |
4266 | insn = PREV_INSN (insn); | |
4267 | ||
4268 | if (need_fake_edge_p (insn)) | |
4269 | { | |
4270 | edge e; | |
4271 | ||
9ff3d2de JL |
4272 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4273 | if (e) | |
4274 | { | |
c41c1387 | 4275 | insert_insn_on_edge (gen_use (const0_rtx), e); |
9ff3d2de JL |
4276 | commit_edge_insertions (); |
4277 | } | |
6de9cd9a DN |
4278 | } |
4279 | } | |
4280 | ||
4281 | /* Now add fake edges to the function exit for any non constant | |
4282 | calls since there is no way that we can determine if they will | |
4283 | return or not... */ | |
4284 | ||
24bd1a0b | 4285 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a DN |
4286 | { |
4287 | basic_block bb = BASIC_BLOCK (i); | |
4288 | rtx insn; | |
4289 | rtx prev_insn; | |
4290 | ||
4291 | if (!bb) | |
4292 | continue; | |
4293 | ||
4294 | if (blocks && !TEST_BIT (blocks, i)) | |
4295 | continue; | |
4296 | ||
4297 | for (insn = BB_END (bb); ; insn = prev_insn) | |
4298 | { | |
4299 | prev_insn = PREV_INSN (insn); | |
4300 | if (need_fake_edge_p (insn)) | |
4301 | { | |
4302 | edge e; | |
4303 | rtx split_at_insn = insn; | |
4304 | ||
4305 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 4306 | remain in the same block as the call. */ |
4b4bf941 | 4307 | if (CALL_P (insn)) |
6de9cd9a DN |
4308 | while (split_at_insn != BB_END (bb) |
4309 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
4310 | split_at_insn = NEXT_INSN (split_at_insn); | |
4311 | ||
4312 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 4313 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
4314 | block in CFG already. Calling make_edge in such case would |
4315 | cause us to mark that edge as fake and remove it later. */ | |
4316 | ||
4317 | #ifdef ENABLE_CHECKING | |
4318 | if (split_at_insn == BB_END (bb)) | |
628f6a4e | 4319 | { |
9ff3d2de JL |
4320 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4321 | gcc_assert (e == NULL); | |
628f6a4e | 4322 | } |
6de9cd9a DN |
4323 | #endif |
4324 | ||
4325 | /* Note that the following may create a new basic block | |
4326 | and renumber the existing basic blocks. */ | |
4327 | if (split_at_insn != BB_END (bb)) | |
4328 | { | |
4329 | e = split_block (bb, split_at_insn); | |
4330 | if (e) | |
4331 | blocks_split++; | |
4332 | } | |
4333 | ||
4334 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
4335 | } | |
4336 | ||
4337 | if (insn == BB_HEAD (bb)) | |
4338 | break; | |
4339 | } | |
4340 | } | |
4341 | ||
4342 | if (blocks_split) | |
4343 | verify_flow_info (); | |
4344 | ||
4345 | return blocks_split; | |
4346 | } | |
4347 | ||
1cb7dfc3 | 4348 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 4349 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
4350 | there is no need to handle this here the loop versioning code handles |
4351 | this. the reason for SECON_HEAD is that it is needed for condition | |
4352 | in trees, and this should be of the same type since it is a hook. */ | |
4353 | static void | |
4354 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
4355 | basic_block second_head ATTRIBUTE_UNUSED, |
4356 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 MH |
4357 | { |
4358 | rtx label, seq, jump; | |
4359 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
4360 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
4361 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
4362 | enum machine_mode mode; | |
4363 | ||
4364 | ||
4365 | label = block_label (first_head); | |
4366 | mode = GET_MODE (op0); | |
4367 | if (mode == VOIDmode) | |
4368 | mode = GET_MODE (op1); | |
4369 | ||
4370 | start_sequence (); | |
4371 | op0 = force_operand (op0, NULL_RTX); | |
4372 | op1 = force_operand (op1, NULL_RTX); | |
4373 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
40e90eac | 4374 | mode, NULL_RTX, NULL_RTX, label, -1); |
1cb7dfc3 MH |
4375 | jump = get_last_insn (); |
4376 | JUMP_LABEL (jump) = label; | |
4377 | LABEL_NUSES (label)++; | |
4378 | seq = get_insns (); | |
4379 | end_sequence (); | |
4380 | ||
4381 | /* Add the new cond , in the new head. */ | |
4382 | emit_insn_after(seq, BB_END(cond_bb)); | |
4383 | } | |
4384 | ||
4385 | ||
4386 | /* Given a block B with unconditional branch at its end, get the | |
4387 | store the return the branch edge and the fall-thru edge in | |
4388 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
4389 | static void | |
4390 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
4391 | edge *fallthru_edge) | |
4392 | { | |
4393 | edge e = EDGE_SUCC (b, 0); | |
4394 | ||
4395 | if (e->flags & EDGE_FALLTHRU) | |
4396 | { | |
4397 | *fallthru_edge = e; | |
4398 | *branch_edge = EDGE_SUCC (b, 1); | |
4399 | } | |
4400 | else | |
4401 | { | |
4402 | *branch_edge = e; | |
4403 | *fallthru_edge = EDGE_SUCC (b, 1); | |
4404 | } | |
4405 | } | |
4406 | ||
5e2d947c JH |
4407 | void |
4408 | init_rtl_bb_info (basic_block bb) | |
4409 | { | |
bcc708fc MM |
4410 | gcc_assert (!bb->il.x.rtl); |
4411 | bb->il.x.head_ = NULL; | |
4412 | bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info (); | |
5e2d947c JH |
4413 | } |
4414 | ||
14fa2cc0 ZD |
4415 | /* Returns true if it is possible to remove edge E by redirecting |
4416 | it to the destination of the other edge from E->src. */ | |
4417 | ||
4418 | static bool | |
9678086d | 4419 | rtl_can_remove_branch_p (const_edge e) |
14fa2cc0 | 4420 | { |
9678086d KG |
4421 | const_basic_block src = e->src; |
4422 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
4423 | const_rtx insn = BB_END (src), set; | |
14fa2cc0 ZD |
4424 | |
4425 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
4426 | if (target == EXIT_BLOCK_PTR) | |
4427 | return false; | |
4428 | ||
4429 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
4430 | return false; | |
4431 | ||
4432 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) | |
4433 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
4434 | return false; | |
4435 | ||
4436 | if (!onlyjump_p (insn) | |
4437 | || tablejump_p (insn, NULL, NULL)) | |
4438 | return false; | |
4439 | ||
4440 | set = single_set (insn); | |
4441 | if (!set || side_effects_p (set)) | |
4442 | return false; | |
4443 | ||
4444 | return true; | |
4445 | } | |
4446 | ||
ffe14686 AM |
4447 | static basic_block |
4448 | rtl_duplicate_bb (basic_block bb) | |
4449 | { | |
4450 | bb = cfg_layout_duplicate_bb (bb); | |
4451 | bb->aux = NULL; | |
4452 | return bb; | |
4453 | } | |
4454 | ||
aa4723d7 SB |
4455 | /* Do book-keeping of basic block BB for the profile consistency checker. |
4456 | If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1 | |
4457 | then do post-pass accounting. Store the counting in RECORD. */ | |
4458 | static void | |
4459 | rtl_account_profile_record (basic_block bb, int after_pass, | |
4460 | struct profile_record *record) | |
4461 | { | |
4462 | rtx insn; | |
4463 | FOR_BB_INSNS (bb, insn) | |
4464 | if (INSN_P (insn)) | |
4465 | { | |
4466 | record->size[after_pass] | |
4467 | += insn_rtx_cost (PATTERN (insn), false); | |
4468 | if (profile_status == PROFILE_READ) | |
4469 | record->time[after_pass] | |
4470 | += insn_rtx_cost (PATTERN (insn), true) * bb->count; | |
4471 | else if (profile_status == PROFILE_GUESSED) | |
4472 | record->time[after_pass] | |
4473 | += insn_rtx_cost (PATTERN (insn), true) * bb->frequency; | |
4474 | } | |
4475 | } | |
4476 | ||
9ee634e3 JH |
4477 | /* Implementation of CFG manipulation for linearized RTL. */ |
4478 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 4479 | "rtl", |
9ee634e3 | 4480 | rtl_verify_flow_info, |
10e9fecc | 4481 | rtl_dump_bb, |
bc35512f | 4482 | rtl_create_basic_block, |
9ee634e3 JH |
4483 | rtl_redirect_edge_and_branch, |
4484 | rtl_redirect_edge_and_branch_force, | |
14fa2cc0 | 4485 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4486 | rtl_delete_block, |
4487 | rtl_split_block, | |
f470c378 | 4488 | rtl_move_block_after, |
bc35512f JH |
4489 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
4490 | rtl_merge_blocks, | |
6de9cd9a DN |
4491 | rtl_predict_edge, |
4492 | rtl_predicted_by_p, | |
ffe14686 AM |
4493 | cfg_layout_can_duplicate_bb_p, |
4494 | rtl_duplicate_bb, | |
f470c378 ZD |
4495 | rtl_split_edge, |
4496 | rtl_make_forwarder_block, | |
6de9cd9a | 4497 | rtl_tidy_fallthru_edge, |
cf103ca4 | 4498 | rtl_force_nonfallthru, |
6de9cd9a DN |
4499 | rtl_block_ends_with_call_p, |
4500 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4501 | rtl_flow_call_edges_add, |
4502 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4503 | NULL, /* execute_on_shrinking_pred */ |
4504 | NULL, /* duplicate loop for trees */ | |
4505 | NULL, /* lv_add_condition_to_bb */ | |
4506 | NULL, /* lv_adjust_loop_header_phi*/ | |
4507 | NULL, /* extract_cond_bb_edges */ | |
df92c640 SB |
4508 | NULL, /* flush_pending_stmts */ |
4509 | rtl_block_empty_p, /* block_empty_p */ | |
4510 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4511 | rtl_account_profile_record, |
9ee634e3 JH |
4512 | }; |
4513 | ||
4514 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
4515 | basic block connected via fallthru edges does not have to be adjacent. | |
4516 | This representation will hopefully become the default one in future | |
4517 | version of the compiler. */ | |
6de9cd9a | 4518 | |
9ee634e3 | 4519 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 4520 | "cfglayout mode", |
bc35512f | 4521 | rtl_verify_flow_info_1, |
10e9fecc | 4522 | rtl_dump_bb, |
bc35512f | 4523 | cfg_layout_create_basic_block, |
9ee634e3 JH |
4524 | cfg_layout_redirect_edge_and_branch, |
4525 | cfg_layout_redirect_edge_and_branch_force, | |
14fa2cc0 | 4526 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4527 | cfg_layout_delete_block, |
4528 | cfg_layout_split_block, | |
f470c378 | 4529 | rtl_move_block_after, |
bc35512f JH |
4530 | cfg_layout_can_merge_blocks_p, |
4531 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
4532 | rtl_predict_edge, |
4533 | rtl_predicted_by_p, | |
4534 | cfg_layout_can_duplicate_bb_p, | |
4535 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
4536 | cfg_layout_split_edge, |
4537 | rtl_make_forwarder_block, | |
cf103ca4 EB |
4538 | NULL, /* tidy_fallthru_edge */ |
4539 | rtl_force_nonfallthru, | |
6de9cd9a DN |
4540 | rtl_block_ends_with_call_p, |
4541 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4542 | rtl_flow_call_edges_add, |
4543 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4544 | NULL, /* execute_on_shrinking_pred */ |
4545 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
4546 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
4547 | NULL, /* lv_adjust_loop_header_phi*/ | |
4548 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
df92c640 SB |
4549 | NULL, /* flush_pending_stmts */ |
4550 | rtl_block_empty_p, /* block_empty_p */ | |
4551 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4552 | rtl_account_profile_record, |
9ee634e3 | 4553 | }; |
78bde837 SB |
4554 | |
4555 | #include "gt-cfgrtl.h" |