]>
Commit | Line | Data |
---|---|---|
ca6c03ca | 1 | /* Control flow graph manipulation code for GNU compiler. |
d1e082c2 | 2 | Copyright (C) 1987-2013 Free Software Foundation, Inc. |
ca6c03ca JH |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it under | |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
ca6c03ca JH |
9 | version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
ca6c03ca | 19 | |
5f0d2358 RK |
20 | /* This file contains low level functions to manipulate the CFG and analyze it |
21 | that are aware of the RTL intermediate language. | |
ca6c03ca JH |
22 | |
23 | Available functionality: | |
bc35512f | 24 | - Basic CFG/RTL manipulation API documented in cfghooks.h |
5f0d2358 | 25 | - CFG-aware instruction chain manipulation |
ca6c03ca | 26 | delete_insn, delete_insn_chain |
bc35512f JH |
27 | - Edge splitting and committing to edges |
28 | insert_insn_on_edge, commit_edge_insertions | |
29 | - CFG updating after insn simplification | |
30 | purge_dead_edges, purge_all_dead_edges | |
ba5e9aca EB |
31 | - CFG fixing after coarse manipulation |
32 | fixup_abnormal_edges | |
bc35512f JH |
33 | |
34 | Functions not supposed for generic use: | |
5f0d2358 | 35 | - Infrastructure to determine quickly basic block for insn |
ca6c03ca | 36 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5f0d2358 | 37 | - Edge redirection with updating and optimizing of insn chain |
bc35512f | 38 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
ca6c03ca JH |
39 | \f |
40 | #include "config.h" | |
41 | #include "system.h" | |
4977bab6 ZW |
42 | #include "coretypes.h" |
43 | #include "tm.h" | |
ca6c03ca | 44 | #include "tree.h" |
ca6c03ca JH |
45 | #include "hard-reg-set.h" |
46 | #include "basic-block.h" | |
47 | #include "regs.h" | |
48 | #include "flags.h" | |
ca6c03ca JH |
49 | #include "function.h" |
50 | #include "except.h" | |
0cbd9993 | 51 | #include "rtl-error.h" |
ca6c03ca JH |
52 | #include "tm_p.h" |
53 | #include "obstack.h" | |
2a34bece | 54 | #include "insn-attr.h" |
0a2ed1f1 | 55 | #include "insn-config.h" |
ff25ef99 | 56 | #include "expr.h" |
9fb32434 | 57 | #include "target.h" |
677f3fa8 | 58 | #include "common/common-target.h" |
1cb7dfc3 | 59 | #include "cfgloop.h" |
5e2d947c | 60 | #include "ggc.h" |
ef330312 | 61 | #include "tree-pass.h" |
6fb5fa3c | 62 | #include "df.h" |
ca6c03ca | 63 | |
78bde837 SB |
64 | /* Holds the interesting leading and trailing notes for the function. |
65 | Only applicable if the CFG is in cfglayout mode. */ | |
66 | static GTY(()) rtx cfg_layout_function_footer; | |
67 | static GTY(()) rtx cfg_layout_function_header; | |
68 | ||
69 | static rtx skip_insns_after_block (basic_block); | |
70 | static void record_effective_endpoints (void); | |
71 | static rtx label_for_bb (basic_block); | |
72 | static void fixup_reorder_chain (void); | |
73 | ||
74 | void verify_insn_chain (void); | |
75 | static void fixup_fallthru_exit_predecessor (void); | |
9678086d KG |
76 | static int can_delete_note_p (const_rtx); |
77 | static int can_delete_label_p (const_rtx); | |
d329e058 | 78 | static basic_block rtl_split_edge (edge); |
f470c378 | 79 | static bool rtl_move_block_after (basic_block, basic_block); |
d329e058 | 80 | static int rtl_verify_flow_info (void); |
f470c378 | 81 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 82 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
83 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
84 | static void cfg_layout_delete_block (basic_block); | |
85 | static void rtl_delete_block (basic_block); | |
86 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
6de9cd9a | 87 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 | 88 | static basic_block rtl_split_block (basic_block, void *); |
a315c44c | 89 | static void rtl_dump_bb (FILE *, basic_block, int, int); |
d329e058 | 90 | static int rtl_verify_flow_info_1 (void); |
f470c378 | 91 | static void rtl_make_forwarder_block (edge); |
ca6c03ca JH |
92 | \f |
93 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 94 | so that we may simply delete it. */ |
ca6c03ca JH |
95 | |
96 | static int | |
9678086d | 97 | can_delete_note_p (const_rtx note) |
ca6c03ca | 98 | { |
cd9c1ca8 RH |
99 | switch (NOTE_KIND (note)) |
100 | { | |
101 | case NOTE_INSN_DELETED: | |
102 | case NOTE_INSN_BASIC_BLOCK: | |
103 | case NOTE_INSN_EPILOGUE_BEG: | |
104 | return true; | |
105 | ||
106 | default: | |
107 | return false; | |
108 | } | |
ca6c03ca JH |
109 | } |
110 | ||
111 | /* True if a given label can be deleted. */ | |
112 | ||
113 | static int | |
9678086d | 114 | can_delete_label_p (const_rtx label) |
ca6c03ca | 115 | { |
5f0d2358 RK |
116 | return (!LABEL_PRESERVE_P (label) |
117 | /* User declared labels must be preserved. */ | |
118 | && LABEL_NAME (label) == 0 | |
610d2478 | 119 | && !in_expr_list_p (forced_labels, label)); |
ca6c03ca JH |
120 | } |
121 | ||
03fbe718 | 122 | /* Delete INSN by patching it out. */ |
ca6c03ca | 123 | |
03fbe718 | 124 | void |
d329e058 | 125 | delete_insn (rtx insn) |
ca6c03ca | 126 | { |
ca6c03ca JH |
127 | rtx note; |
128 | bool really_delete = true; | |
129 | ||
4b4bf941 | 130 | if (LABEL_P (insn)) |
ca6c03ca JH |
131 | { |
132 | /* Some labels can't be directly removed from the INSN chain, as they | |
c22cacf3 MS |
133 | might be references via variables, constant pool etc. |
134 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
ca6c03ca JH |
135 | if (! can_delete_label_p (insn)) |
136 | { | |
137 | const char *name = LABEL_NAME (insn); | |
5e5df392 | 138 | basic_block bb = BLOCK_FOR_INSN (insn); |
03fbe718 | 139 | rtx bb_note = NEXT_INSN (insn); |
ca6c03ca JH |
140 | |
141 | really_delete = false; | |
142 | PUT_CODE (insn, NOTE); | |
a38e7aa5 | 143 | NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL; |
6773e15f | 144 | NOTE_DELETED_LABEL_NAME (insn) = name; |
03fbe718 | 145 | |
0f33baa9 | 146 | /* If the note following the label starts a basic block, and the |
5e5df392 | 147 | label is a member of the same basic block, interchange the two. */ |
0f33baa9 TV |
148 | if (bb_note != NULL_RTX |
149 | && NOTE_INSN_BASIC_BLOCK_P (bb_note) | |
5e5df392 TV |
150 | && bb != NULL |
151 | && bb == BLOCK_FOR_INSN (bb_note)) | |
03fbe718 TV |
152 | { |
153 | reorder_insns_nobb (insn, insn, bb_note); | |
154 | BB_HEAD (bb) = bb_note; | |
155 | if (BB_END (bb) == bb_note) | |
156 | BB_END (bb) = insn; | |
157 | } | |
ca6c03ca | 158 | } |
5f0d2358 | 159 | |
ca6c03ca JH |
160 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
161 | } | |
162 | ||
163 | if (really_delete) | |
164 | { | |
cda94cbb | 165 | /* If this insn has already been deleted, something is very wrong. */ |
341c100f | 166 | gcc_assert (!INSN_DELETED_P (insn)); |
1f397f45 SB |
167 | if (INSN_P (insn)) |
168 | df_insn_delete (insn); | |
ca6c03ca JH |
169 | remove_insn (insn); |
170 | INSN_DELETED_P (insn) = 1; | |
171 | } | |
172 | ||
173 | /* If deleting a jump, decrement the use count of the label. Deleting | |
174 | the label itself should happen in the normal course of block merging. */ | |
cf7c4aa6 | 175 | if (JUMP_P (insn)) |
9295a326 | 176 | { |
cf7c4aa6 HPN |
177 | if (JUMP_LABEL (insn) |
178 | && LABEL_P (JUMP_LABEL (insn))) | |
179 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
180 | ||
181 | /* If there are more targets, remove them too. */ | |
182 | while ((note | |
183 | = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX | |
4b4bf941 | 184 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
185 | { |
186 | LABEL_NUSES (XEXP (note, 0))--; | |
187 | remove_note (insn, note); | |
188 | } | |
189 | } | |
ca6c03ca | 190 | |
cf7c4aa6 HPN |
191 | /* Also if deleting any insn that references a label as an operand. */ |
192 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX | |
193 | && LABEL_P (XEXP (note, 0))) | |
194 | { | |
195 | LABEL_NUSES (XEXP (note, 0))--; | |
196 | remove_note (insn, note); | |
197 | } | |
198 | ||
481683e1 | 199 | if (JUMP_TABLE_DATA_P (insn)) |
ca6c03ca JH |
200 | { |
201 | rtx pat = PATTERN (insn); | |
202 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
203 | int len = XVECLEN (pat, diff_vec_p); | |
204 | int i; | |
205 | ||
206 | for (i = 0; i < len; i++) | |
a124fcda RH |
207 | { |
208 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
209 | ||
210 | /* When deleting code in bulk (e.g. removing many unreachable | |
211 | blocks) we can delete a label that's a target of the vector | |
212 | before deleting the vector itself. */ | |
4b4bf941 | 213 | if (!NOTE_P (label)) |
a124fcda RH |
214 | LABEL_NUSES (label)--; |
215 | } | |
ca6c03ca | 216 | } |
ca6c03ca JH |
217 | } |
218 | ||
3dec4024 | 219 | /* Like delete_insn but also purge dead edges from BB. */ |
9ed7b221 | 220 | |
03fbe718 | 221 | void |
d329e058 | 222 | delete_insn_and_edges (rtx insn) |
3dec4024 | 223 | { |
3dec4024 JH |
224 | bool purge = false; |
225 | ||
ba4f7968 | 226 | if (INSN_P (insn) |
3dec4024 | 227 | && BLOCK_FOR_INSN (insn) |
a813c111 | 228 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 | 229 | purge = true; |
03fbe718 | 230 | delete_insn (insn); |
3dec4024 JH |
231 | if (purge) |
232 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
3dec4024 JH |
233 | } |
234 | ||
ca6c03ca | 235 | /* Unlink a chain of insns between START and FINISH, leaving notes |
a7b87f73 ZD |
236 | that must be paired. If CLEAR_BB is true, we set bb field for |
237 | insns that cannot be removed to NULL. */ | |
ca6c03ca JH |
238 | |
239 | void | |
a7b87f73 | 240 | delete_insn_chain (rtx start, rtx finish, bool clear_bb) |
ca6c03ca | 241 | { |
03fbe718 | 242 | rtx prev, current; |
ca6c03ca | 243 | |
5f0d2358 RK |
244 | /* Unchain the insns one by one. It would be quicker to delete all of these |
245 | with a single unchaining, rather than one at a time, but we need to keep | |
246 | the NOTE's. */ | |
03fbe718 | 247 | current = finish; |
ca6c03ca JH |
248 | while (1) |
249 | { | |
03fbe718 TV |
250 | prev = PREV_INSN (current); |
251 | if (NOTE_P (current) && !can_delete_note_p (current)) | |
ca6c03ca JH |
252 | ; |
253 | else | |
03fbe718 | 254 | delete_insn (current); |
ca6c03ca | 255 | |
03fbe718 TV |
256 | if (clear_bb && !INSN_DELETED_P (current)) |
257 | set_block_for_insn (current, NULL); | |
a7b87f73 | 258 | |
03fbe718 | 259 | if (current == start) |
ca6c03ca | 260 | break; |
03fbe718 | 261 | current = prev; |
ca6c03ca JH |
262 | } |
263 | } | |
264 | \f | |
5f0d2358 RK |
265 | /* Create a new basic block consisting of the instructions between HEAD and END |
266 | inclusive. This function is designed to allow fast BB construction - reuses | |
267 | the note and basic block struct in BB_NOTE, if any and do not grow | |
268 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
269 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
270 | and HEAD can be NULL to create basic block at the end of INSN chain. |
271 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
272 | |
273 | basic_block | |
d329e058 | 274 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
275 | { |
276 | basic_block bb; | |
277 | ||
278 | if (bb_note | |
ca6c03ca JH |
279 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
280 | && bb->aux == NULL) | |
281 | { | |
282 | /* If we found an existing note, thread it back onto the chain. */ | |
283 | ||
284 | rtx after; | |
285 | ||
4b4bf941 | 286 | if (LABEL_P (head)) |
ca6c03ca JH |
287 | after = head; |
288 | else | |
289 | { | |
290 | after = PREV_INSN (head); | |
291 | head = bb_note; | |
292 | } | |
293 | ||
294 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 295 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
296 | } |
297 | else | |
298 | { | |
299 | /* Otherwise we must create a note and a basic block structure. */ | |
300 | ||
301 | bb = alloc_block (); | |
302 | ||
5e2d947c | 303 | init_rtl_bb_info (bb); |
ca6c03ca | 304 | if (!head && !end) |
5f0d2358 RK |
305 | head = end = bb_note |
306 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 307 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
308 | { |
309 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
310 | if (head == end) | |
311 | end = bb_note; | |
312 | } | |
313 | else | |
314 | { | |
315 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
316 | head = bb_note; | |
317 | if (!end) | |
318 | end = head; | |
319 | } | |
5f0d2358 | 320 | |
ca6c03ca JH |
321 | NOTE_BASIC_BLOCK (bb_note) = bb; |
322 | } | |
323 | ||
324 | /* Always include the bb note in the block. */ | |
325 | if (NEXT_INSN (end) == bb_note) | |
326 | end = bb_note; | |
327 | ||
a813c111 SB |
328 | BB_HEAD (bb) = head; |
329 | BB_END (bb) = end; | |
852c6ec7 | 330 | bb->index = last_basic_block++; |
5e2d947c | 331 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 332 | link_block (bb, after); |
68f9b844 | 333 | SET_BASIC_BLOCK (bb->index, bb); |
6fb5fa3c | 334 | df_bb_refs_record (bb->index, false); |
ba4f7968 | 335 | update_bb_for_insn (bb); |
076c7ab8 | 336 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
337 | |
338 | /* Tag the block so that we know it has been used when considering | |
339 | other basic block notes. */ | |
340 | bb->aux = bb; | |
341 | ||
342 | return bb; | |
343 | } | |
344 | ||
5f0d2358 | 345 | /* Create new basic block consisting of instructions in between HEAD and END |
ffe14686 AM |
346 | and place it to the BB chain after block AFTER. END can be NULL to |
347 | create a new empty basic block before HEAD. Both END and HEAD can be | |
348 | NULL to create basic block at the end of INSN chain. */ | |
ca6c03ca | 349 | |
bc35512f JH |
350 | static basic_block |
351 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 352 | { |
ae50c0cb | 353 | rtx head = (rtx) headp, end = (rtx) endp; |
ca6c03ca | 354 | basic_block bb; |
0b17ab2f | 355 | |
7eca0767 | 356 | /* Grow the basic block array if needed. */ |
9771b263 | 357 | if ((size_t) last_basic_block >= basic_block_info->length ()) |
7eca0767 JH |
358 | { |
359 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; | |
9771b263 | 360 | vec_safe_grow_cleared (basic_block_info, new_size); |
7eca0767 | 361 | } |
0b17ab2f | 362 | |
bf77398c | 363 | n_basic_blocks++; |
ca6c03ca | 364 | |
852c6ec7 | 365 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
366 | bb->aux = NULL; |
367 | return bb; | |
368 | } | |
bc35512f JH |
369 | |
370 | static basic_block | |
371 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
372 | { | |
373 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
374 | ||
bc35512f JH |
375 | return newbb; |
376 | } | |
ca6c03ca JH |
377 | \f |
378 | /* Delete the insns in a (non-live) block. We physically delete every | |
379 | non-deleted-note insn, and update the flow graph appropriately. | |
380 | ||
381 | Return nonzero if we deleted an exception handler. */ | |
382 | ||
383 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
384 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
385 | ||
f0fda11c | 386 | static void |
d329e058 | 387 | rtl_delete_block (basic_block b) |
ca6c03ca | 388 | { |
96370780 | 389 | rtx insn, end; |
ca6c03ca JH |
390 | |
391 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
392 | label for an exception handler which can't be reached. We need |
393 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 394 | insn = BB_HEAD (b); |
ca6c03ca | 395 | |
96370780 | 396 | end = get_last_bb_insn (b); |
ca6c03ca JH |
397 | |
398 | /* Selectively delete the entire chain. */ | |
a813c111 | 399 | BB_HEAD (b) = NULL; |
a7b87f73 ZD |
400 | delete_insn_chain (insn, end, true); |
401 | ||
6fb5fa3c DB |
402 | |
403 | if (dump_file) | |
404 | fprintf (dump_file, "deleting block %d\n", b->index); | |
405 | df_bb_delete (b->index); | |
ca6c03ca JH |
406 | } |
407 | \f | |
852c6ec7 | 408 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
409 | |
410 | void | |
d329e058 | 411 | compute_bb_for_insn (void) |
ca6c03ca | 412 | { |
e0082a72 | 413 | basic_block bb; |
ca6c03ca | 414 | |
e0082a72 | 415 | FOR_EACH_BB (bb) |
ca6c03ca | 416 | { |
a813c111 | 417 | rtx end = BB_END (bb); |
5f0d2358 | 418 | rtx insn; |
ca6c03ca | 419 | |
a813c111 | 420 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 421 | { |
ba4f7968 | 422 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
423 | if (insn == end) |
424 | break; | |
ca6c03ca JH |
425 | } |
426 | } | |
427 | } | |
428 | ||
429 | /* Release the basic_block_for_insn array. */ | |
430 | ||
c2924966 | 431 | unsigned int |
d329e058 | 432 | free_bb_for_insn (void) |
ca6c03ca | 433 | { |
ba4f7968 JH |
434 | rtx insn; |
435 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
4b4bf941 | 436 | if (!BARRIER_P (insn)) |
ba4f7968 | 437 | BLOCK_FOR_INSN (insn) = NULL; |
c2924966 | 438 | return 0; |
ca6c03ca JH |
439 | } |
440 | ||
2a34bece EB |
441 | static unsigned int |
442 | rest_of_pass_free_cfg (void) | |
443 | { | |
444 | #ifdef DELAY_SLOTS | |
445 | /* The resource.c machinery uses DF but the CFG isn't guaranteed to be | |
446 | valid at that point so it would be too late to call df_analyze. */ | |
447 | if (optimize > 0 && flag_delayed_branch) | |
ad78b8a6 EB |
448 | { |
449 | df_note_add_problem (); | |
450 | df_analyze (); | |
451 | } | |
2a34bece EB |
452 | #endif |
453 | ||
454 | free_bb_for_insn (); | |
455 | return 0; | |
456 | } | |
457 | ||
8ddbbcae | 458 | struct rtl_opt_pass pass_free_cfg = |
ef330312 | 459 | { |
8ddbbcae JH |
460 | { |
461 | RTL_PASS, | |
e0a42b0f | 462 | "*free_cfg", /* name */ |
2b4e6bf1 | 463 | OPTGROUP_NONE, /* optinfo_flags */ |
ef330312 | 464 | NULL, /* gate */ |
2a34bece | 465 | rest_of_pass_free_cfg, /* execute */ |
ef330312 PB |
466 | NULL, /* sub */ |
467 | NULL, /* next */ | |
468 | 0, /* static_pass_number */ | |
7072a650 | 469 | TV_NONE, /* tv_id */ |
ef330312 PB |
470 | 0, /* properties_required */ |
471 | 0, /* properties_provided */ | |
472 | PROP_cfg, /* properties_destroyed */ | |
473 | 0, /* todo_flags_start */ | |
474 | 0, /* todo_flags_finish */ | |
8ddbbcae | 475 | } |
ef330312 PB |
476 | }; |
477 | ||
91278841 AP |
478 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
479 | rtx | |
480 | entry_of_function (void) | |
481 | { | |
c22cacf3 | 482 | return (n_basic_blocks > NUM_FIXED_BLOCKS ? |
24bd1a0b | 483 | BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ()); |
91278841 AP |
484 | } |
485 | ||
11b904a1 BS |
486 | /* Emit INSN at the entry point of the function, ensuring that it is only |
487 | executed once per function. */ | |
488 | void | |
489 | emit_insn_at_entry (rtx insn) | |
490 | { | |
491 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->succs); | |
492 | edge e = ei_safe_edge (ei); | |
5419bc7f | 493 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
494 | |
495 | insert_insn_on_edge (insn, e); | |
496 | commit_edge_insertions (); | |
497 | } | |
498 | ||
6c3d0e31 | 499 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
b8698a0f | 500 | (or BARRIER if found) and notify df of the bb change. |
6c3d0e31 SP |
501 | The insn chain range is inclusive |
502 | (i.e. both BEGIN and END will be updated. */ | |
ca6c03ca | 503 | |
6c3d0e31 SP |
504 | static void |
505 | update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb) | |
ca6c03ca JH |
506 | { |
507 | rtx insn; | |
508 | ||
6c3d0e31 SP |
509 | end = NEXT_INSN (end); |
510 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
63642d5a AO |
511 | if (!BARRIER_P (insn)) |
512 | df_insn_change_bb (insn, bb); | |
ca6c03ca | 513 | } |
6c3d0e31 SP |
514 | |
515 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
516 | and notify df of the change. */ | |
517 | ||
518 | void | |
519 | update_bb_for_insn (basic_block bb) | |
520 | { | |
521 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
522 | } | |
523 | ||
532aafad SB |
524 | \f |
525 | /* Like active_insn_p, except keep the return value clobber around | |
526 | even after reload. */ | |
527 | ||
528 | static bool | |
529 | flow_active_insn_p (const_rtx insn) | |
530 | { | |
531 | if (active_insn_p (insn)) | |
532 | return true; | |
533 | ||
534 | /* A clobber of the function return value exists for buggy | |
535 | programs that fail to return a value. Its effect is to | |
536 | keep the return value from being live across the entire | |
537 | function. If we allow it to be skipped, we introduce the | |
538 | possibility for register lifetime confusion. */ | |
539 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
540 | && REG_P (XEXP (PATTERN (insn), 0)) | |
541 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
542 | return true; | |
543 | ||
544 | return false; | |
545 | } | |
546 | ||
547 | /* Return true if the block has no effect and only forwards control flow to | |
548 | its single destination. */ | |
532aafad SB |
549 | |
550 | bool | |
2407343c | 551 | contains_no_active_insn_p (const_basic_block bb) |
532aafad SB |
552 | { |
553 | rtx insn; | |
554 | ||
555 | if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR | |
556 | || !single_succ_p (bb)) | |
557 | return false; | |
558 | ||
2407343c JR |
559 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) |
560 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
561 | return false; | |
562 | ||
563 | return (!INSN_P (insn) | |
564 | || (JUMP_P (insn) && simplejump_p (insn)) | |
565 | || !flow_active_insn_p (insn)); | |
566 | } | |
567 | ||
568 | /* Likewise, but protect loop latches, headers and preheaders. */ | |
569 | /* FIXME: Make this a cfg hook. */ | |
570 | ||
571 | bool | |
572 | forwarder_block_p (const_basic_block bb) | |
573 | { | |
574 | if (!contains_no_active_insn_p (bb)) | |
575 | return false; | |
576 | ||
532aafad SB |
577 | /* Protect loop latches, headers and preheaders. */ |
578 | if (current_loops) | |
579 | { | |
580 | basic_block dest; | |
581 | if (bb->loop_father->header == bb) | |
582 | return false; | |
583 | dest = EDGE_SUCC (bb, 0)->dest; | |
584 | if (dest->loop_father->header == dest) | |
585 | return false; | |
586 | } | |
587 | ||
2407343c | 588 | return true; |
532aafad SB |
589 | } |
590 | ||
591 | /* Return nonzero if we can reach target from src by falling through. */ | |
592 | /* FIXME: Make this a cfg hook. */ | |
593 | ||
594 | bool | |
595 | can_fallthru (basic_block src, basic_block target) | |
596 | { | |
597 | rtx insn = BB_END (src); | |
598 | rtx insn2; | |
599 | edge e; | |
600 | edge_iterator ei; | |
601 | ||
602 | if (target == EXIT_BLOCK_PTR) | |
603 | return true; | |
604 | if (src->next_bb != target) | |
605 | return 0; | |
606 | FOR_EACH_EDGE (e, ei, src->succs) | |
607 | if (e->dest == EXIT_BLOCK_PTR | |
608 | && e->flags & EDGE_FALLTHRU) | |
609 | return 0; | |
610 | ||
611 | insn2 = BB_HEAD (target); | |
612 | if (insn2 && !active_insn_p (insn2)) | |
613 | insn2 = next_active_insn (insn2); | |
614 | ||
615 | /* ??? Later we may add code to move jump tables offline. */ | |
616 | return next_active_insn (insn) == insn2; | |
617 | } | |
618 | ||
619 | /* Return nonzero if we could reach target from src by falling through, | |
620 | if the target was made adjacent. If we already have a fall-through | |
621 | edge to the exit block, we can't do that. */ | |
622 | static bool | |
623 | could_fall_through (basic_block src, basic_block target) | |
624 | { | |
625 | edge e; | |
626 | edge_iterator ei; | |
627 | ||
628 | if (target == EXIT_BLOCK_PTR) | |
629 | return true; | |
630 | FOR_EACH_EDGE (e, ei, src->succs) | |
631 | if (e->dest == EXIT_BLOCK_PTR | |
632 | && e->flags & EDGE_FALLTHRU) | |
633 | return 0; | |
634 | return true; | |
635 | } | |
ca6c03ca | 636 | \f |
ef2be249 RS |
637 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
638 | rtx | |
639 | bb_note (basic_block bb) | |
640 | { | |
641 | rtx note; | |
642 | ||
643 | note = BB_HEAD (bb); | |
644 | if (LABEL_P (note)) | |
645 | note = NEXT_INSN (note); | |
646 | ||
647 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
648 | return note; | |
649 | } | |
650 | ||
6fb5fa3c DB |
651 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
652 | note associated with the BLOCK. */ | |
653 | ||
654 | static rtx | |
655 | first_insn_after_basic_block_note (basic_block block) | |
656 | { | |
657 | rtx insn; | |
658 | ||
659 | /* Get the first instruction in the block. */ | |
660 | insn = BB_HEAD (block); | |
661 | ||
662 | if (insn == NULL_RTX) | |
663 | return NULL_RTX; | |
664 | if (LABEL_P (insn)) | |
665 | insn = NEXT_INSN (insn); | |
666 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
667 | ||
668 | return NEXT_INSN (insn); | |
669 | } | |
670 | ||
f470c378 ZD |
671 | /* Creates a new basic block just after basic block B by splitting |
672 | everything after specified instruction I. */ | |
ca6c03ca | 673 | |
f470c378 | 674 | static basic_block |
d329e058 | 675 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
676 | { |
677 | basic_block new_bb; | |
ae50c0cb | 678 | rtx insn = (rtx) insnp; |
f470c378 | 679 | edge e; |
628f6a4e | 680 | edge_iterator ei; |
ca6c03ca | 681 | |
f470c378 ZD |
682 | if (!insn) |
683 | { | |
684 | insn = first_insn_after_basic_block_note (bb); | |
685 | ||
686 | if (insn) | |
b5b8b0ac AO |
687 | { |
688 | rtx next = insn; | |
689 | ||
690 | insn = PREV_INSN (insn); | |
691 | ||
692 | /* If the block contains only debug insns, insn would have | |
693 | been NULL in a non-debug compilation, and then we'd end | |
694 | up emitting a DELETED note. For -fcompare-debug | |
695 | stability, emit the note too. */ | |
696 | if (insn != BB_END (bb) | |
697 | && DEBUG_INSN_P (next) | |
698 | && DEBUG_INSN_P (BB_END (bb))) | |
699 | { | |
700 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
701 | next = NEXT_INSN (next); | |
702 | ||
703 | if (next == BB_END (bb)) | |
704 | emit_note_after (NOTE_INSN_DELETED, next); | |
705 | } | |
706 | } | |
f470c378 ZD |
707 | else |
708 | insn = get_last_insn (); | |
709 | } | |
710 | ||
711 | /* We probably should check type of the insn so that we do not create | |
712 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
713 | bother. */ | |
714 | if (insn == BB_END (bb)) | |
715 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
716 | |
717 | /* Create the new basic block. */ | |
a813c111 | 718 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 719 | BB_COPY_PARTITION (new_bb, bb); |
a813c111 | 720 | BB_END (bb) = insn; |
ca6c03ca JH |
721 | |
722 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
723 | new_bb->succs = bb->succs; |
724 | bb->succs = NULL; | |
725 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
726 | e->src = new_bb; |
727 | ||
6fb5fa3c DB |
728 | /* The new block starts off being dirty. */ |
729 | df_set_bb_dirty (bb); | |
f470c378 | 730 | return new_bb; |
bc35512f JH |
731 | } |
732 | ||
9be94227 EB |
733 | /* Return true if the single edge between blocks A and B is the only place |
734 | in RTL which holds some unique locus. */ | |
735 | ||
736 | static bool | |
737 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
738 | { | |
5368224f | 739 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
740 | rtx insn, end; |
741 | ||
2f13f2de | 742 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
9be94227 EB |
743 | return false; |
744 | ||
745 | /* First scan block A backward. */ | |
746 | insn = BB_END (a); | |
747 | end = PREV_INSN (BB_HEAD (a)); | |
5368224f | 748 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
9be94227 EB |
749 | insn = PREV_INSN (insn); |
750 | ||
5368224f | 751 | if (insn != end && INSN_LOCATION (insn) == goto_locus) |
9be94227 EB |
752 | return false; |
753 | ||
754 | /* Then scan block B forward. */ | |
755 | insn = BB_HEAD (b); | |
756 | if (insn) | |
757 | { | |
758 | end = NEXT_INSN (BB_END (b)); | |
759 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
760 | insn = NEXT_INSN (insn); | |
761 | ||
5368224f DC |
762 | if (insn != end && INSN_HAS_LOCATION (insn) |
763 | && INSN_LOCATION (insn) == goto_locus) | |
9be94227 EB |
764 | return false; |
765 | } | |
766 | ||
767 | return true; | |
768 | } | |
769 | ||
770 | /* If the single edge between blocks A and B is the only place in RTL which | |
771 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
772 | ||
773 | static void | |
774 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
775 | { | |
776 | if (!unique_locus_on_edge_between_p (a, b)) | |
777 | return; | |
778 | ||
779 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); | |
5368224f | 780 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
781 | } |
782 | ||
ca6c03ca | 783 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 784 | are already contiguous. */ |
ca6c03ca | 785 | |
bc35512f JH |
786 | static void |
787 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 788 | { |
a813c111 | 789 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca | 790 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
b5b8b0ac | 791 | rtx b_debug_start = b_end, b_debug_end = b_end; |
50a36e42 | 792 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
ca6c03ca JH |
793 | int b_empty = 0; |
794 | ||
6fb5fa3c | 795 | if (dump_file) |
50a36e42 EB |
796 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
797 | a->index); | |
6fb5fa3c | 798 | |
b5b8b0ac AO |
799 | while (DEBUG_INSN_P (b_end)) |
800 | b_end = PREV_INSN (b_debug_start = b_end); | |
801 | ||
ca6c03ca | 802 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 803 | if (LABEL_P (b_head)) |
ca6c03ca JH |
804 | { |
805 | /* Detect basic blocks with nothing but a label. This can happen | |
806 | in particular at the end of a function. */ | |
807 | if (b_head == b_end) | |
808 | b_empty = 1; | |
5f0d2358 | 809 | |
ca6c03ca JH |
810 | del_first = del_last = b_head; |
811 | b_head = NEXT_INSN (b_head); | |
812 | } | |
813 | ||
5f0d2358 RK |
814 | /* Delete the basic block note and handle blocks containing just that |
815 | note. */ | |
ca6c03ca JH |
816 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
817 | { | |
818 | if (b_head == b_end) | |
819 | b_empty = 1; | |
820 | if (! del_last) | |
821 | del_first = b_head; | |
5f0d2358 | 822 | |
ca6c03ca JH |
823 | del_last = b_head; |
824 | b_head = NEXT_INSN (b_head); | |
825 | } | |
826 | ||
827 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 828 | if (JUMP_P (a_end)) |
ca6c03ca JH |
829 | { |
830 | rtx prev; | |
831 | ||
832 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 833 | if (!NOTE_P (prev) |
a38e7aa5 | 834 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
a813c111 | 835 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
836 | break; |
837 | ||
838 | del_first = a_end; | |
839 | ||
840 | #ifdef HAVE_cc0 | |
841 | /* If this was a conditional jump, we need to also delete | |
842 | the insn that set cc0. */ | |
843 | if (only_sets_cc0_p (prev)) | |
844 | { | |
845 | rtx tmp = prev; | |
5f0d2358 | 846 | |
ca6c03ca JH |
847 | prev = prev_nonnote_insn (prev); |
848 | if (!prev) | |
a813c111 | 849 | prev = BB_HEAD (a); |
ca6c03ca JH |
850 | del_first = tmp; |
851 | } | |
852 | #endif | |
853 | ||
854 | a_end = PREV_INSN (del_first); | |
855 | } | |
4b4bf941 | 856 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
857 | del_first = NEXT_INSN (a_end); |
858 | ||
ca6c03ca JH |
859 | /* Delete everything marked above as well as crap that might be |
860 | hanging out between the two blocks. */ | |
9be94227 EB |
861 | BB_END (a) = a_end; |
862 | BB_HEAD (b) = b_empty ? NULL_RTX : b_head; | |
a7b87f73 | 863 | delete_insn_chain (del_first, del_last, true); |
ca6c03ca | 864 | |
9be94227 EB |
865 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
866 | some unique locus, emit a nop with that locus in between. */ | |
867 | if (!optimize) | |
868 | { | |
869 | emit_nop_for_unique_locus_between (a, b); | |
870 | a_end = BB_END (a); | |
871 | } | |
872 | ||
ca6c03ca JH |
873 | /* Reassociate the insns of B with A. */ |
874 | if (!b_empty) | |
875 | { | |
b5b8b0ac | 876 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5f0d2358 | 877 | |
9be94227 EB |
878 | BB_END (a) = b_debug_end; |
879 | BB_HEAD (b) = NULL_RTX; | |
b5b8b0ac AO |
880 | } |
881 | else if (b_end != b_debug_end) | |
882 | { | |
883 | /* Move any deleted labels and other notes between the end of A | |
884 | and the debug insns that make up B after the debug insns, | |
885 | bringing the debug insns into A while keeping the notes after | |
886 | the end of A. */ | |
887 | if (NEXT_INSN (a_end) != b_debug_start) | |
888 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
889 | b_debug_end); | |
890 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
9be94227 | 891 | BB_END (a) = b_debug_end; |
ca6c03ca | 892 | } |
5f0d2358 | 893 | |
6fb5fa3c | 894 | df_bb_delete (b->index); |
50a36e42 EB |
895 | |
896 | /* If B was a forwarder block, propagate the locus on the edge. */ | |
fbc68f2a DC |
897 | if (forwarder_p |
898 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) | |
50a36e42 EB |
899 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
900 | ||
901 | if (dump_file) | |
902 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
ca6c03ca | 903 | } |
bc35512f | 904 | |
6fb5fa3c | 905 | |
bc35512f | 906 | /* Return true when block A and B can be merged. */ |
9678086d | 907 | |
b48d0358 DN |
908 | static bool |
909 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
bc35512f | 910 | { |
750054a2 CT |
911 | /* If we are partitioning hot/cold basic blocks, we don't want to |
912 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
913 | and cold sections. |
914 | ||
8e8d5162 | 915 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
916 | be optimizable (or blocks that appear to be mergeable), but which really |
917 | must be left untouched (they are required to make it safely across | |
918 | partition boundaries). See the comments at the top of | |
8e8d5162 | 919 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 920 | |
87c8b4be | 921 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 922 | return false; |
750054a2 | 923 | |
7d776ee2 RG |
924 | /* Protect the loop latches. */ |
925 | if (current_loops && b->loop_father->latch == b) | |
926 | return false; | |
927 | ||
bc35512f | 928 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
929 | return (single_succ_p (a) |
930 | && single_succ (a) == b | |
931 | && single_pred_p (b) | |
628f6a4e | 932 | && a != b |
bc35512f | 933 | /* Must be simple edge. */ |
c5cbcccf | 934 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f JH |
935 | && a->next_bb == b |
936 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR | |
937 | /* If the jump insn has side effects, | |
938 | we can't kill the edge. */ | |
4b4bf941 | 939 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 940 | || (reload_completed |
a813c111 | 941 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 942 | } |
ca6c03ca | 943 | \f |
5f0d2358 RK |
944 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
945 | exist. */ | |
ca6c03ca JH |
946 | |
947 | rtx | |
d329e058 | 948 | block_label (basic_block block) |
ca6c03ca JH |
949 | { |
950 | if (block == EXIT_BLOCK_PTR) | |
951 | return NULL_RTX; | |
5f0d2358 | 952 | |
4b4bf941 | 953 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 954 | { |
a813c111 | 955 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 956 | } |
5f0d2358 | 957 | |
a813c111 | 958 | return BB_HEAD (block); |
ca6c03ca JH |
959 | } |
960 | ||
961 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
962 | instruction by unconditional jump or removing jump completely. This can |
963 | apply only if all edges now point to the same block. The parameters and | |
964 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 965 | |
6de9cd9a | 966 | edge |
bc35512f | 967 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
968 | { |
969 | basic_block src = e->src; | |
a813c111 | 970 | rtx insn = BB_END (src), kill_from; |
e1233a7d | 971 | rtx set; |
ca6c03ca | 972 | int fallthru = 0; |
750054a2 CT |
973 | |
974 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
975 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
976 | and cold sections. |
977 | ||
978 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
979 | be optimizable (or blocks that appear to be mergeable), but which really |
980 | must be left untouched (they are required to make it safely across | |
981 | partition boundaries). See the comments at the top of | |
8e8d5162 | 982 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 983 | |
87c8b4be CT |
984 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) |
985 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
9cf84a3c | 986 | return NULL; |
750054a2 | 987 | |
6a66a8a7 KH |
988 | /* We can replace or remove a complex jump only when we have exactly |
989 | two edges. Also, if we have exactly one outgoing edge, we can | |
990 | redirect that. */ | |
991 | if (EDGE_COUNT (src->succs) >= 3 | |
992 | /* Verify that all targets will be TARGET. Specifically, the | |
993 | edge that is not E must also go to TARGET. */ | |
994 | || (EDGE_COUNT (src->succs) == 2 | |
995 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
996 | return NULL; | |
5f0d2358 | 997 | |
6a66a8a7 | 998 | if (!onlyjump_p (insn)) |
6de9cd9a | 999 | return NULL; |
3348b696 | 1000 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 1001 | return NULL; |
ca6c03ca JH |
1002 | |
1003 | /* Avoid removing branch with side effects. */ | |
1004 | set = single_set (insn); | |
1005 | if (!set || side_effects_p (set)) | |
6de9cd9a | 1006 | return NULL; |
ca6c03ca JH |
1007 | |
1008 | /* In case we zap a conditional jump, we'll need to kill | |
1009 | the cc0 setter too. */ | |
1010 | kill_from = insn; | |
1011 | #ifdef HAVE_cc0 | |
9caea4a7 RS |
1012 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
1013 | && only_sets_cc0_p (PREV_INSN (insn))) | |
ca6c03ca JH |
1014 | kill_from = PREV_INSN (insn); |
1015 | #endif | |
1016 | ||
1017 | /* See if we can create the fallthru edge. */ | |
bc35512f | 1018 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 1019 | { |
c263766c RH |
1020 | if (dump_file) |
1021 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
1022 | fallthru = 1; |
1023 | ||
eaec9b3d | 1024 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
1025 | if (in_cfglayout) |
1026 | { | |
bcc708fc | 1027 | rtx insn = BB_FOOTER (src); |
bc35512f | 1028 | |
a7b87f73 | 1029 | delete_insn_chain (kill_from, BB_END (src), false); |
bc35512f JH |
1030 | |
1031 | /* Remove barriers but keep jumptables. */ | |
1032 | while (insn) | |
1033 | { | |
4b4bf941 | 1034 | if (BARRIER_P (insn)) |
bc35512f JH |
1035 | { |
1036 | if (PREV_INSN (insn)) | |
1037 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1038 | else | |
bcc708fc | 1039 | BB_FOOTER (src) = NEXT_INSN (insn); |
bc35512f JH |
1040 | if (NEXT_INSN (insn)) |
1041 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1042 | } | |
4b4bf941 | 1043 | if (LABEL_P (insn)) |
bc35512f JH |
1044 | break; |
1045 | insn = NEXT_INSN (insn); | |
1046 | } | |
1047 | } | |
1048 | else | |
a7b87f73 ZD |
1049 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)), |
1050 | false); | |
ca6c03ca | 1051 | } |
5f0d2358 | 1052 | |
ca6c03ca JH |
1053 | /* If this already is simplejump, redirect it. */ |
1054 | else if (simplejump_p (insn)) | |
1055 | { | |
1056 | if (e->dest == target) | |
6de9cd9a | 1057 | return NULL; |
c263766c RH |
1058 | if (dump_file) |
1059 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 1060 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
1061 | if (!redirect_jump (insn, block_label (target), 0)) |
1062 | { | |
341c100f NS |
1063 | gcc_assert (target == EXIT_BLOCK_PTR); |
1064 | return NULL; | |
6ee3c8e4 | 1065 | } |
ca6c03ca | 1066 | } |
5f0d2358 | 1067 | |
6ee3c8e4 JJ |
1068 | /* Cannot do anything for target exit block. */ |
1069 | else if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 1070 | return NULL; |
6ee3c8e4 | 1071 | |
ca6c03ca JH |
1072 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1073 | else | |
1074 | { | |
1075 | rtx target_label = block_label (target); | |
eb5b8ad4 | 1076 | rtx barrier, label, table; |
ca6c03ca | 1077 | |
a7102479 | 1078 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
a813c111 | 1079 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 1080 | LABEL_NUSES (target_label)++; |
c263766c RH |
1081 | if (dump_file) |
1082 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 1083 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 1084 | |
4da2eb6b | 1085 | |
ba4807a0 LB |
1086 | delete_insn_chain (kill_from, insn, false); |
1087 | ||
4da2eb6b RH |
1088 | /* Recognize a tablejump that we are converting to a |
1089 | simple jump and remove its associated CODE_LABEL | |
1090 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
ba4807a0 LB |
1091 | if (tablejump_p (insn, &label, &table)) |
1092 | delete_insn_chain (label, table, false); | |
eb5b8ad4 | 1093 | |
a813c111 | 1094 | barrier = next_nonnote_insn (BB_END (src)); |
4b4bf941 | 1095 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 1096 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
1097 | else |
1098 | { | |
a813c111 | 1099 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
1100 | { |
1101 | /* Move the jump before barrier so that the notes | |
1102 | which originally were or were created before jump table are | |
1103 | inside the basic block. */ | |
a813c111 | 1104 | rtx new_insn = BB_END (src); |
5d693491 | 1105 | |
6c3d0e31 SP |
1106 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1107 | PREV_INSN (barrier), src); | |
5d693491 JZ |
1108 | |
1109 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
1110 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
1111 | ||
1112 | NEXT_INSN (new_insn) = barrier; | |
1113 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
1114 | ||
1115 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
1116 | PREV_INSN (barrier) = new_insn; | |
1117 | } | |
1118 | } | |
ca6c03ca JH |
1119 | } |
1120 | ||
1121 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 1122 | if (!single_succ_p (src)) |
628f6a4e | 1123 | remove_edge (e); |
c5cbcccf | 1124 | gcc_assert (single_succ_p (src)); |
628f6a4e | 1125 | |
c5cbcccf | 1126 | e = single_succ_edge (src); |
ca6c03ca JH |
1127 | if (fallthru) |
1128 | e->flags = EDGE_FALLTHRU; | |
1129 | else | |
1130 | e->flags = 0; | |
5f0d2358 | 1131 | |
ca6c03ca JH |
1132 | e->probability = REG_BR_PROB_BASE; |
1133 | e->count = src->count; | |
1134 | ||
ca6c03ca JH |
1135 | if (e->dest != target) |
1136 | redirect_edge_succ (e, target); | |
6de9cd9a | 1137 | return e; |
ca6c03ca JH |
1138 | } |
1139 | ||
4e3825db MM |
1140 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1141 | instruction INSN so that it reaches block NEW. Do this | |
1142 | only when it originally reached block OLD. Return true if this | |
1143 | worked or the original target wasn't OLD, return false if redirection | |
1144 | doesn't work. */ | |
1145 | ||
1146 | static bool | |
1147 | patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb) | |
ca6c03ca JH |
1148 | { |
1149 | rtx tmp; | |
ca6c03ca | 1150 | /* Recognize a tablejump and adjust all matching cases. */ |
e1233a7d | 1151 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
1152 | { |
1153 | rtvec vec; | |
1154 | int j; | |
4e3825db | 1155 | rtx new_label = block_label (new_bb); |
ca6c03ca | 1156 | |
4e3825db MM |
1157 | if (new_bb == EXIT_BLOCK_PTR) |
1158 | return false; | |
ca6c03ca JH |
1159 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
1160 | vec = XVEC (PATTERN (tmp), 0); | |
1161 | else | |
1162 | vec = XVEC (PATTERN (tmp), 1); | |
1163 | ||
1164 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1165 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1166 | { | |
1167 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1168 | --LABEL_NUSES (old_label); | |
1169 | ++LABEL_NUSES (new_label); | |
1170 | } | |
1171 | ||
f9da5064 | 1172 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
1173 | if ((tmp = single_set (insn)) != NULL |
1174 | && SET_DEST (tmp) == pc_rtx | |
1175 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
1176 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
1177 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
1178 | { | |
4c33cb26 | 1179 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
1180 | new_label); |
1181 | --LABEL_NUSES (old_label); | |
1182 | ++LABEL_NUSES (new_label); | |
1183 | } | |
1184 | } | |
1c384bf1 RH |
1185 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1186 | { | |
1187 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
1188 | rtx new_label, note; | |
1189 | ||
1190 | if (new_bb == EXIT_BLOCK_PTR) | |
1191 | return false; | |
1192 | new_label = block_label (new_bb); | |
1193 | ||
1194 | for (i = 0; i < n; ++i) | |
1195 | { | |
1196 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1197 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1198 | if (XEXP (old_ref, 0) == old_label) | |
1199 | { | |
1200 | ASM_OPERANDS_LABEL (tmp, i) | |
1201 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1202 | --LABEL_NUSES (old_label); | |
1203 | ++LABEL_NUSES (new_label); | |
1204 | } | |
1205 | } | |
1206 | ||
1207 | if (JUMP_LABEL (insn) == old_label) | |
1208 | { | |
1209 | JUMP_LABEL (insn) = new_label; | |
1210 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1211 | if (note) | |
1212 | remove_note (insn, note); | |
1213 | } | |
1214 | else | |
1215 | { | |
1216 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1217 | if (note) | |
1218 | remove_note (insn, note); | |
1219 | if (JUMP_LABEL (insn) != new_label | |
1220 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1221 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1222 | } | |
3b5fda81 JJ |
1223 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1224 | != NULL_RTX) | |
1225 | XEXP (note, 0) = new_label; | |
1c384bf1 | 1226 | } |
ca6c03ca JH |
1227 | else |
1228 | { | |
1229 | /* ?? We may play the games with moving the named labels from | |
1230 | one basic block to the other in case only one computed_jump is | |
1231 | available. */ | |
5f0d2358 RK |
1232 | if (computed_jump_p (insn) |
1233 | /* A return instruction can't be redirected. */ | |
1234 | || returnjump_p (insn)) | |
4e3825db | 1235 | return false; |
6ee3c8e4 | 1236 | |
4e3825db | 1237 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
6ee3c8e4 | 1238 | { |
4e3825db MM |
1239 | /* If the insn doesn't go where we think, we're confused. */ |
1240 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1241 | ||
1242 | /* If the substitution doesn't succeed, die. This can happen | |
1243 | if the back end emitted unrecognizable instructions or if | |
1244 | target is exit block on some arches. */ | |
1245 | if (!redirect_jump (insn, block_label (new_bb), 0)) | |
1246 | { | |
1247 | gcc_assert (new_bb == EXIT_BLOCK_PTR); | |
1248 | return false; | |
1249 | } | |
6ee3c8e4 | 1250 | } |
ca6c03ca | 1251 | } |
4e3825db MM |
1252 | return true; |
1253 | } | |
1254 | ||
1255 | ||
1256 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1257 | NULL on failure */ | |
1258 | static edge | |
1259 | redirect_branch_edge (edge e, basic_block target) | |
1260 | { | |
1261 | rtx old_label = BB_HEAD (e->dest); | |
1262 | basic_block src = e->src; | |
1263 | rtx insn = BB_END (src); | |
1264 | ||
1265 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1266 | if (e->flags & EDGE_FALLTHRU) | |
1267 | return NULL; | |
1268 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1269 | return NULL; | |
1270 | ||
1271 | if (!currently_expanding_to_rtl) | |
1272 | { | |
1273 | if (!patch_jump_insn (insn, old_label, target)) | |
1274 | return NULL; | |
1275 | } | |
1276 | else | |
1277 | /* When expanding this BB might actually contain multiple | |
1278 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1279 | Redirect all of those that match our label. */ | |
0f346928 | 1280 | FOR_BB_INSNS (src, insn) |
4e3825db MM |
1281 | if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target)) |
1282 | return NULL; | |
ca6c03ca | 1283 | |
c263766c RH |
1284 | if (dump_file) |
1285 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 1286 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 1287 | |
ca6c03ca | 1288 | if (e->dest != target) |
6de9cd9a | 1289 | e = redirect_edge_succ_nodup (e, target); |
6fb5fa3c | 1290 | |
6de9cd9a | 1291 | return e; |
bc35512f JH |
1292 | } |
1293 | ||
1294 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on | |
1295 | expense of adding new instructions or reordering basic blocks. | |
1296 | ||
1297 | Function can be also called with edge destination equivalent to the TARGET. | |
1298 | Then it should try the simplifications and do nothing if none is possible. | |
1299 | ||
6de9cd9a DN |
1300 | Return edge representing the branch if transformation succeeded. Return NULL |
1301 | on failure. | |
1302 | We still return NULL in case E already destinated TARGET and we didn't | |
1303 | managed to simplify instruction stream. */ | |
bc35512f | 1304 | |
6de9cd9a | 1305 | static edge |
5671bf27 | 1306 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 1307 | { |
6de9cd9a | 1308 | edge ret; |
f345f21a JH |
1309 | basic_block src = e->src; |
1310 | ||
bc35512f | 1311 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 1312 | return NULL; |
bc35512f | 1313 | |
3348b696 | 1314 | if (e->dest == target) |
6de9cd9a | 1315 | return e; |
3348b696 | 1316 | |
6de9cd9a | 1317 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a | 1318 | { |
6fb5fa3c | 1319 | df_set_bb_dirty (src); |
6de9cd9a | 1320 | return ret; |
f345f21a | 1321 | } |
bc35512f | 1322 | |
6de9cd9a DN |
1323 | ret = redirect_branch_edge (e, target); |
1324 | if (!ret) | |
1325 | return NULL; | |
5f0d2358 | 1326 | |
6fb5fa3c | 1327 | df_set_bb_dirty (src); |
6de9cd9a | 1328 | return ret; |
ca6c03ca JH |
1329 | } |
1330 | ||
4fe9b91c | 1331 | /* Like force_nonfallthru below, but additionally performs redirection |
26898771 BS |
1332 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1333 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1334 | simple_return_rtx, indicating which kind of returnjump to create. | |
1335 | It should be NULL otherwise. */ | |
ca6c03ca | 1336 | |
dc0ff1c8 | 1337 | basic_block |
26898771 | 1338 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
ca6c03ca | 1339 | { |
a3716585 | 1340 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
1341 | rtx note; |
1342 | edge new_edge; | |
a3716585 | 1343 | int abnormal_edge_flags = 0; |
a3e6a37b | 1344 | bool asm_goto_edge = false; |
7241571e | 1345 | int loc; |
ca6c03ca | 1346 | |
cb9a1d9b JH |
1347 | /* In the case the last instruction is conditional jump to the next |
1348 | instruction, first redirect the jump itself and then continue | |
b20b352b | 1349 | by creating a basic block afterwards to redirect fallthru edge. */ |
cb9a1d9b | 1350 | if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR |
a813c111 | 1351 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 1352 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1353 | { |
1354 | rtx note; | |
58e6ae30 | 1355 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1356 | bool redirected; |
cb9a1d9b | 1357 | |
341c100f NS |
1358 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1359 | gcc_assert (redirected); | |
c22cacf3 | 1360 | |
a813c111 | 1361 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1362 | if (note) |
1363 | { | |
1364 | int prob = INTVAL (XEXP (note, 0)); | |
1365 | ||
1366 | b->probability = prob; | |
8ddb5a29 | 1367 | /* Update this to use GCOV_COMPUTE_SCALE. */ |
cb9a1d9b JH |
1368 | b->count = e->count * prob / REG_BR_PROB_BASE; |
1369 | e->probability -= e->probability; | |
1370 | e->count -= b->count; | |
1371 | if (e->probability < 0) | |
1372 | e->probability = 0; | |
1373 | if (e->count < 0) | |
1374 | e->count = 0; | |
1375 | } | |
1376 | } | |
1377 | ||
ca6c03ca | 1378 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1379 | { |
1380 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1381 | edge. | |
1382 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1383 | one and create separate abnormal edge to original destination. |
a3716585 | 1384 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1385 | gcc_assert (e->dest == target); |
ee44c28d SB |
1386 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1387 | e->flags &= EDGE_FALLTHRU; | |
a3716585 | 1388 | } |
341c100f | 1389 | else |
24c545ff | 1390 | { |
341c100f NS |
1391 | gcc_assert (e->flags & EDGE_FALLTHRU); |
1392 | if (e->src == ENTRY_BLOCK_PTR) | |
1393 | { | |
1394 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1395 | at the start of the function which we use to add the new |
1396 | jump. */ | |
1397 | edge tmp; | |
1398 | edge_iterator ei; | |
1399 | bool found = false; | |
c22cacf3 | 1400 | |
628f6a4e | 1401 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, ENTRY_BLOCK_PTR); |
c22cacf3 | 1402 | |
341c100f NS |
1403 | /* Change the existing edge's source to be the new block, and add |
1404 | a new edge from the entry block to the new block. */ | |
1405 | e->src = bb; | |
628f6a4e BE |
1406 | for (ei = ei_start (ENTRY_BLOCK_PTR->succs); (tmp = ei_safe_edge (ei)); ) |
1407 | { | |
1408 | if (tmp == e) | |
1409 | { | |
9771b263 | 1410 | ENTRY_BLOCK_PTR->succs->unordered_remove (ei.index); |
628f6a4e BE |
1411 | found = true; |
1412 | break; | |
1413 | } | |
1414 | else | |
1415 | ei_next (&ei); | |
1416 | } | |
c22cacf3 | 1417 | |
628f6a4e | 1418 | gcc_assert (found); |
c22cacf3 | 1419 | |
9771b263 | 1420 | vec_safe_push (bb->succs, e); |
341c100f NS |
1421 | make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU); |
1422 | } | |
24c545ff BS |
1423 | } |
1424 | ||
a3e6a37b | 1425 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
891ca07d | 1426 | don't point to the target or fallthru label. */ |
a3e6a37b JJ |
1427 | if (JUMP_P (BB_END (e->src)) |
1428 | && target != EXIT_BLOCK_PTR | |
a3e6a37b JJ |
1429 | && (e->flags & EDGE_FALLTHRU) |
1430 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
ca6c03ca | 1431 | { |
a3e6a37b | 1432 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
5d68b7e6 | 1433 | bool adjust_jump_target = false; |
a3e6a37b JJ |
1434 | |
1435 | for (i = 0; i < n; ++i) | |
891ca07d JJ |
1436 | { |
1437 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
5d68b7e6 JJ |
1438 | { |
1439 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--; | |
1440 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1441 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++; | |
1442 | adjust_jump_target = true; | |
1443 | } | |
891ca07d | 1444 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) |
a3e6a37b | 1445 | asm_goto_edge = true; |
891ca07d | 1446 | } |
5d68b7e6 JJ |
1447 | if (adjust_jump_target) |
1448 | { | |
1449 | rtx insn = BB_END (e->src), note; | |
1450 | rtx old_label = BB_HEAD (e->dest); | |
1451 | rtx new_label = BB_HEAD (target); | |
1452 | ||
1453 | if (JUMP_LABEL (insn) == old_label) | |
1454 | { | |
1455 | JUMP_LABEL (insn) = new_label; | |
1456 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1457 | if (note) | |
1458 | remove_note (insn, note); | |
1459 | } | |
1460 | else | |
1461 | { | |
1462 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1463 | if (note) | |
1464 | remove_note (insn, note); | |
1465 | if (JUMP_LABEL (insn) != new_label | |
1466 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1467 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1468 | } | |
1469 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) | |
1470 | != NULL_RTX) | |
1471 | XEXP (note, 0) = new_label; | |
1472 | } | |
a3e6a37b JJ |
1473 | } |
1474 | ||
1475 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1476 | { | |
1477 | gcov_type count = e->count; | |
1478 | int probability = e->probability; | |
ca6c03ca | 1479 | /* Create the new structures. */ |
31a78298 | 1480 | |
79019985 RH |
1481 | /* If the old block ended with a tablejump, skip its table |
1482 | by searching forward from there. Otherwise start searching | |
1483 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1484 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1485 | note = BB_END (e->src); | |
31a78298 RH |
1486 | note = NEXT_INSN (note); |
1487 | ||
31a78298 | 1488 | jump_block = create_basic_block (note, NULL, e->src); |
a3e6a37b | 1489 | jump_block->count = count; |
ca6c03ca | 1490 | jump_block->frequency = EDGE_FREQUENCY (e); |
ca6c03ca | 1491 | |
750054a2 CT |
1492 | /* Make sure new block ends up in correct hot/cold section. */ |
1493 | ||
076c7ab8 | 1494 | BB_COPY_PARTITION (jump_block, e->src); |
9fb32434 | 1495 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1496 | && targetm_common.have_named_sections |
87c8b4be CT |
1497 | && JUMP_P (BB_END (jump_block)) |
1498 | && !any_condjump_p (BB_END (jump_block)) | |
1499 | && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING)) | |
65c5f2a6 | 1500 | add_reg_note (BB_END (jump_block), REG_CROSSING_JUMP, NULL_RTX); |
c22cacf3 | 1501 | |
ca6c03ca JH |
1502 | /* Wire edge in. */ |
1503 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
a3e6a37b JJ |
1504 | new_edge->probability = probability; |
1505 | new_edge->count = count; | |
ca6c03ca JH |
1506 | |
1507 | /* Redirect old edge. */ | |
1508 | redirect_edge_pred (e, jump_block); | |
1509 | e->probability = REG_BR_PROB_BASE; | |
1510 | ||
a3e6a37b JJ |
1511 | /* If asm goto has any label refs to target's label, |
1512 | add also edge from asm goto bb to target. */ | |
1513 | if (asm_goto_edge) | |
1514 | { | |
1515 | new_edge->probability /= 2; | |
1516 | new_edge->count /= 2; | |
1517 | jump_block->count /= 2; | |
1518 | jump_block->frequency /= 2; | |
1519 | new_edge = make_edge (new_edge->src, target, | |
1520 | e->flags & ~EDGE_FALLTHRU); | |
1521 | new_edge->probability = probability - probability / 2; | |
1522 | new_edge->count = count - count / 2; | |
1523 | } | |
1524 | ||
ca6c03ca JH |
1525 | new_bb = jump_block; |
1526 | } | |
1527 | else | |
1528 | jump_block = e->src; | |
5f0d2358 | 1529 | |
2f13f2de | 1530 | loc = e->goto_locus; |
ca6c03ca JH |
1531 | e->flags &= ~EDGE_FALLTHRU; |
1532 | if (target == EXIT_BLOCK_PTR) | |
1533 | { | |
26898771 BS |
1534 | if (jump_label == ret_rtx) |
1535 | { | |
cf22ce3c | 1536 | #ifdef HAVE_return |
26898771 | 1537 | emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc); |
cf22ce3c | 1538 | #else |
26898771 | 1539 | gcc_unreachable (); |
cf22ce3c | 1540 | #endif |
26898771 BS |
1541 | } |
1542 | else | |
1543 | { | |
1544 | gcc_assert (jump_label == simple_return_rtx); | |
1545 | #ifdef HAVE_simple_return | |
1546 | emit_jump_insn_after_setloc (gen_simple_return (), | |
1547 | BB_END (jump_block), loc); | |
1548 | #else | |
1549 | gcc_unreachable (); | |
1550 | #endif | |
1551 | } | |
387748de | 1552 | set_return_jump_label (BB_END (jump_block)); |
ca6c03ca JH |
1553 | } |
1554 | else | |
1555 | { | |
1556 | rtx label = block_label (target); | |
7241571e | 1557 | emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc); |
a813c111 | 1558 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1559 | LABEL_NUSES (label)++; |
1560 | } | |
5f0d2358 | 1561 | |
a813c111 | 1562 | emit_barrier_after (BB_END (jump_block)); |
ca6c03ca JH |
1563 | redirect_edge_succ_nodup (e, target); |
1564 | ||
a3716585 JH |
1565 | if (abnormal_edge_flags) |
1566 | make_edge (src, target, abnormal_edge_flags); | |
1567 | ||
b8698a0f | 1568 | df_mark_solutions_dirty (); |
ca6c03ca JH |
1569 | return new_bb; |
1570 | } | |
1571 | ||
1572 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1573 | (and possibly create new basic block) to make edge non-fallthru. | |
1574 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1575 | |
cf103ca4 EB |
1576 | static basic_block |
1577 | rtl_force_nonfallthru (edge e) | |
ca6c03ca | 1578 | { |
26898771 | 1579 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
ca6c03ca JH |
1580 | } |
1581 | ||
1582 | /* Redirect edge even at the expense of creating new jump insn or | |
1583 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1584 | Conversion must be possible. */ |
ca6c03ca | 1585 | |
9ee634e3 | 1586 | static basic_block |
d329e058 | 1587 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1588 | { |
5f0d2358 RK |
1589 | if (redirect_edge_and_branch (e, target) |
1590 | || e->dest == target) | |
ca6c03ca JH |
1591 | return NULL; |
1592 | ||
1593 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1594 | and redirect newly created simplejump. */ | |
6fb5fa3c | 1595 | df_set_bb_dirty (e->src); |
26898771 | 1596 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
ca6c03ca JH |
1597 | } |
1598 | ||
1599 | /* The given edge should potentially be a fallthru edge. If that is in | |
1600 | fact true, delete the jump and barriers that are in the way. */ | |
1601 | ||
f470c378 ZD |
1602 | static void |
1603 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1604 | { |
1605 | rtx q; | |
f470c378 ZD |
1606 | basic_block b = e->src, c = b->next_bb; |
1607 | ||
ca6c03ca JH |
1608 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1609 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1610 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1611 | |
1612 | We can also wind up with a sequence of undeletable labels between | |
1613 | one block and the next. | |
1614 | ||
1615 | So search through a sequence of barriers, labels, and notes for | |
1616 | the head of block C and assert that we really do fall through. */ | |
1617 | ||
a813c111 | 1618 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1619 | if (INSN_P (q)) |
1620 | return; | |
ca6c03ca JH |
1621 | |
1622 | /* Remove what will soon cease being the jump insn from the source block. | |
1623 | If block B consisted only of this single jump, turn it into a deleted | |
1624 | note. */ | |
a813c111 | 1625 | q = BB_END (b); |
4b4bf941 | 1626 | if (JUMP_P (q) |
ca6c03ca JH |
1627 | && onlyjump_p (q) |
1628 | && (any_uncondjump_p (q) | |
c5cbcccf | 1629 | || single_succ_p (b))) |
ca6c03ca JH |
1630 | { |
1631 | #ifdef HAVE_cc0 | |
1632 | /* If this was a conditional jump, we need to also delete | |
1633 | the insn that set cc0. */ | |
1634 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1635 | q = PREV_INSN (q); | |
1636 | #endif | |
1637 | ||
1638 | q = PREV_INSN (q); | |
ca6c03ca JH |
1639 | } |
1640 | ||
1641 | /* Selectively unlink the sequence. */ | |
a813c111 | 1642 | if (q != PREV_INSN (BB_HEAD (c))) |
a7b87f73 | 1643 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
ca6c03ca JH |
1644 | |
1645 | e->flags |= EDGE_FALLTHRU; | |
1646 | } | |
ca6c03ca | 1647 | \f |
f470c378 ZD |
1648 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1649 | ||
1650 | static bool | |
1651 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1652 | basic_block after ATTRIBUTE_UNUSED) | |
1653 | { | |
1654 | return false; | |
1655 | } | |
1656 | ||
ca6c03ca | 1657 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1658 | The edge must not be abnormal. |
ca6c03ca JH |
1659 | |
1660 | ??? The code generally expects to be called on critical edges. | |
1661 | The case of a block ending in an unconditional jump to a | |
1662 | block with multiple predecessors is not handled optimally. */ | |
1663 | ||
8ce33230 | 1664 | static basic_block |
d329e058 | 1665 | rtl_split_edge (edge edge_in) |
ca6c03ca JH |
1666 | { |
1667 | basic_block bb; | |
ca6c03ca JH |
1668 | rtx before; |
1669 | ||
1670 | /* Abnormal edges cannot be split. */ | |
341c100f | 1671 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1672 | |
1673 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1674 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1675 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1676 | { | |
0fd4b31d | 1677 | edge e = find_fallthru_edge (edge_in->dest->preds); |
ca6c03ca JH |
1678 | |
1679 | if (e) | |
1680 | force_nonfallthru (e); | |
1681 | } | |
1682 | ||
96e82e0a ZD |
1683 | /* Create the basic block note. */ |
1684 | if (edge_in->dest != EXIT_BLOCK_PTR) | |
a813c111 | 1685 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1686 | else |
1687 | before = NULL_RTX; | |
1688 | ||
623a66fa | 1689 | /* If this is a fall through edge to the exit block, the blocks might be |
ffe14686 AM |
1690 | not adjacent, and the right place is after the source. */ |
1691 | if ((edge_in->flags & EDGE_FALLTHRU) && edge_in->dest == EXIT_BLOCK_PTR) | |
623a66fa R |
1692 | { |
1693 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1694 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1695 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1696 | } |
1697 | else | |
9fb32434 CT |
1698 | { |
1699 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
076c7ab8 ZW |
1700 | /* ??? Why not edge_in->dest->prev_bb here? */ |
1701 | BB_COPY_PARTITION (bb, edge_in->dest); | |
9fb32434 | 1702 | } |
ca6c03ca | 1703 | |
4977bab6 | 1704 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1705 | |
4d6922ee | 1706 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1707 | jump instruction to target our new block. */ |
1708 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1709 | { | |
341c100f NS |
1710 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1711 | gcc_assert (redirected); | |
ca6c03ca JH |
1712 | } |
1713 | else | |
3b5fda81 JJ |
1714 | { |
1715 | if (edge_in->src != ENTRY_BLOCK_PTR) | |
1716 | { | |
1717 | /* For asm goto even splitting of fallthru edge might | |
1718 | need insn patching, as other labels might point to the | |
1719 | old label. */ | |
1720 | rtx last = BB_END (edge_in->src); | |
1721 | if (last | |
1722 | && JUMP_P (last) | |
1723 | && edge_in->dest != EXIT_BLOCK_PTR | |
1724 | && extract_asm_operands (PATTERN (last)) != NULL_RTX | |
1725 | && patch_jump_insn (last, before, bb)) | |
1726 | df_set_bb_dirty (edge_in->src); | |
1727 | } | |
1728 | redirect_edge_succ (edge_in, bb); | |
1729 | } | |
ca6c03ca JH |
1730 | |
1731 | return bb; | |
1732 | } | |
1733 | ||
1734 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1735 | The new instructions and basic blocks (if any) will not appear in the | |
1736 | CFG until commit_edge_insertions is called. */ | |
1737 | ||
1738 | void | |
d329e058 | 1739 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1740 | { |
1741 | /* We cannot insert instructions on an abnormal critical edge. | |
1742 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1743 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1744 | |
6de9cd9a | 1745 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1746 | start_sequence (); |
1747 | else | |
6de9cd9a | 1748 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1749 | |
1750 | emit_insn (pattern); | |
1751 | ||
6de9cd9a | 1752 | e->insns.r = get_insns (); |
ca6c03ca JH |
1753 | end_sequence (); |
1754 | } | |
1755 | ||
1756 | /* Update the CFG for the instructions queued on edge E. */ | |
1757 | ||
4e3825db | 1758 | void |
2ac66157 | 1759 | commit_one_edge_insertion (edge e) |
ca6c03ca JH |
1760 | { |
1761 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
898c90c0 | 1762 | basic_block bb; |
ca6c03ca JH |
1763 | |
1764 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1765 | insns = e->insns.r; |
1766 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1767 | |
898c90c0 EB |
1768 | /* Figure out where to put these insns. If the destination has |
1769 | one predecessor, insert there. Except for the exit block. */ | |
1770 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR) | |
ca6c03ca | 1771 | { |
898c90c0 EB |
1772 | bb = e->dest; |
1773 | ||
1774 | /* Get the location correct wrt a code label, and "nice" wrt | |
1775 | a basic block note, and before everything else. */ | |
1776 | tmp = BB_HEAD (bb); | |
1777 | if (LABEL_P (tmp)) | |
1778 | tmp = NEXT_INSN (tmp); | |
1779 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1780 | tmp = NEXT_INSN (tmp); | |
1781 | if (tmp == BB_HEAD (bb)) | |
1782 | before = tmp; | |
1783 | else if (tmp) | |
1784 | after = PREV_INSN (tmp); | |
1785 | else | |
1786 | after = get_last_insn (); | |
1787 | } | |
3dec4024 | 1788 | |
898c90c0 EB |
1789 | /* If the source has one successor and the edge is not abnormal, |
1790 | insert there. Except for the entry block. */ | |
1791 | else if ((e->flags & EDGE_ABNORMAL) == 0 | |
1792 | && single_succ_p (e->src) | |
1793 | && e->src != ENTRY_BLOCK_PTR) | |
1794 | { | |
1795 | bb = e->src; | |
3dec4024 | 1796 | |
898c90c0 EB |
1797 | /* It is possible to have a non-simple jump here. Consider a target |
1798 | where some forms of unconditional jumps clobber a register. This | |
1799 | happens on the fr30 for example. | |
ca6c03ca | 1800 | |
898c90c0 EB |
1801 | We know this block has a single successor, so we can just emit |
1802 | the queued insns before the jump. */ | |
1803 | if (JUMP_P (BB_END (bb))) | |
1804 | before = BB_END (bb); | |
3dec4024 JH |
1805 | else |
1806 | { | |
898c90c0 EB |
1807 | /* We'd better be fallthru, or we've lost track of what's what. */ |
1808 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
750054a2 | 1809 | |
898c90c0 | 1810 | after = BB_END (bb); |
ca6c03ca JH |
1811 | } |
1812 | } | |
1813 | ||
898c90c0 EB |
1814 | /* Otherwise we must split the edge. */ |
1815 | else | |
1816 | { | |
1817 | bb = split_edge (e); | |
1818 | after = BB_END (bb); | |
ca6c03ca | 1819 | |
898c90c0 | 1820 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1821 | && targetm_common.have_named_sections |
898c90c0 EB |
1822 | && e->src != ENTRY_BLOCK_PTR |
1823 | && BB_PARTITION (e->src) == BB_COLD_PARTITION | |
1824 | && !(e->flags & EDGE_CROSSING) | |
1825 | && JUMP_P (after) | |
1826 | && !any_condjump_p (after) | |
1827 | && (single_succ_edge (bb)->flags & EDGE_CROSSING)) | |
1828 | add_reg_note (after, REG_CROSSING_JUMP, NULL_RTX); | |
1829 | } | |
1830 | ||
1831 | /* Now that we've found the spot, do the insertion. */ | |
ca6c03ca JH |
1832 | if (before) |
1833 | { | |
6fb5fa3c | 1834 | emit_insn_before_noloc (insns, before, bb); |
ca6c03ca JH |
1835 | last = prev_nonnote_insn (before); |
1836 | } | |
1837 | else | |
6fb5fa3c | 1838 | last = emit_insn_after_noloc (insns, after, bb); |
ca6c03ca JH |
1839 | |
1840 | if (returnjump_p (last)) | |
1841 | { | |
1842 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
1843 | This is not currently a problem because this only happens |
1844 | for the (single) epilogue, which already has a fallthru edge | |
1845 | to EXIT. */ | |
ca6c03ca | 1846 | |
c5cbcccf | 1847 | e = single_succ_edge (bb); |
341c100f | 1848 | gcc_assert (e->dest == EXIT_BLOCK_PTR |
c5cbcccf | 1849 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 1850 | |
5f0d2358 | 1851 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 1852 | emit_barrier_after (last); |
0b17ab2f | 1853 | |
ca6c03ca JH |
1854 | if (before) |
1855 | delete_insn (before); | |
1856 | } | |
341c100f NS |
1857 | else |
1858 | gcc_assert (!JUMP_P (last)); | |
ca6c03ca JH |
1859 | } |
1860 | ||
1861 | /* Update the CFG for all queued instructions. */ | |
1862 | ||
1863 | void | |
d329e058 | 1864 | commit_edge_insertions (void) |
ca6c03ca | 1865 | { |
ca6c03ca JH |
1866 | basic_block bb; |
1867 | ||
1868 | #ifdef ENABLE_CHECKING | |
1869 | verify_flow_info (); | |
1870 | #endif | |
1871 | ||
e0082a72 | 1872 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
ca6c03ca | 1873 | { |
628f6a4e BE |
1874 | edge e; |
1875 | edge_iterator ei; | |
ca6c03ca | 1876 | |
628f6a4e BE |
1877 | FOR_EACH_EDGE (e, ei, bb->succs) |
1878 | if (e->insns.r) | |
cf103ca4 | 1879 | commit_one_edge_insertion (e); |
3dec4024 | 1880 | } |
ca6c03ca JH |
1881 | } |
1882 | \f | |
6fb5fa3c | 1883 | |
f470c378 | 1884 | /* Print out RTL-specific basic block information (live information |
a315c44c SB |
1885 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
1886 | documented in dumpfile.h. */ | |
ca6c03ca | 1887 | |
10e9fecc | 1888 | static void |
a315c44c | 1889 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags) |
ca6c03ca JH |
1890 | { |
1891 | rtx insn; | |
1892 | rtx last; | |
f470c378 | 1893 | char *s_indent; |
ca6c03ca | 1894 | |
ae50c0cb | 1895 | s_indent = (char *) alloca ((size_t) indent + 1); |
400e39e3 | 1896 | memset (s_indent, ' ', (size_t) indent); |
f470c378 | 1897 | s_indent[indent] = '\0'; |
b8698a0f | 1898 | |
a315c44c | 1899 | if (df && (flags & TDF_DETAILS)) |
6fb5fa3c DB |
1900 | { |
1901 | df_dump_top (bb, outf); | |
1902 | putc ('\n', outf); | |
1903 | } | |
ca6c03ca | 1904 | |
68cc3174 EB |
1905 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK) |
1906 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; | |
1907 | insn = NEXT_INSN (insn)) | |
a315c44c | 1908 | { |
7b19209f SB |
1909 | if (flags & TDF_DETAILS) |
1910 | df_dump_insn_top (insn, outf); | |
a315c44c SB |
1911 | if (! (flags & TDF_SLIM)) |
1912 | print_rtl_single (outf, insn); | |
1913 | else | |
1914 | dump_insn_slim (outf, insn); | |
7b19209f SB |
1915 | if (flags & TDF_DETAILS) |
1916 | df_dump_insn_bottom (insn, outf); | |
a315c44c SB |
1917 | } |
1918 | ||
1919 | if (df && (flags & TDF_DETAILS)) | |
6fb5fa3c DB |
1920 | { |
1921 | df_dump_bottom (bb, outf); | |
1922 | putc ('\n', outf); | |
1923 | } | |
1924 | ||
ca6c03ca JH |
1925 | } |
1926 | \f | |
c4669594 SB |
1927 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
1928 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
1929 | in dumpfile.h. */ | |
ca6c03ca JH |
1930 | |
1931 | void | |
a315c44c | 1932 | print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags) |
ca6c03ca | 1933 | { |
22ea9ec0 | 1934 | const_rtx tmp_rtx; |
ca6c03ca JH |
1935 | if (rtx_first == 0) |
1936 | fprintf (outf, "(nil)\n"); | |
1937 | else | |
1938 | { | |
ca6c03ca JH |
1939 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
1940 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
1941 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
1942 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
1943 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
e0082a72 ZD |
1944 | basic_block bb; |
1945 | ||
c4669594 SB |
1946 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
1947 | insns, but the CFG is not maintained so the basic block info | |
1948 | is not reliable. Therefore it's omitted from the dumps. */ | |
1949 | if (! (cfun->curr_properties & PROP_cfg)) | |
1950 | flags &= ~TDF_BLOCKS; | |
1951 | ||
6fb5fa3c DB |
1952 | if (df) |
1953 | df_dump_start (outf); | |
1954 | ||
c4669594 | 1955 | if (flags & TDF_BLOCKS) |
ca6c03ca | 1956 | { |
c4669594 | 1957 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1958 | { |
c4669594 SB |
1959 | rtx x; |
1960 | ||
1961 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
1962 | end[INSN_UID (BB_END (bb))] = bb; | |
1963 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
1964 | { | |
1965 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 1966 | |
c4669594 SB |
1967 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
1968 | state = IN_ONE_BB; | |
1969 | in_bb_p[INSN_UID (x)] = state; | |
ca6c03ca | 1970 | |
c4669594 SB |
1971 | if (x == BB_END (bb)) |
1972 | break; | |
1973 | } | |
ca6c03ca JH |
1974 | } |
1975 | } | |
1976 | ||
1977 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
1978 | { | |
c4669594 SB |
1979 | if (flags & TDF_BLOCKS) |
1980 | { | |
1981 | bb = start[INSN_UID (tmp_rtx)]; | |
1982 | if (bb != NULL) | |
1983 | { | |
1984 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false); | |
1985 | if (df && (flags & TDF_DETAILS)) | |
1986 | df_dump_top (bb, outf); | |
1987 | } | |
ca6c03ca | 1988 | |
c4669594 SB |
1989 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
1990 | && !NOTE_P (tmp_rtx) | |
1991 | && !BARRIER_P (tmp_rtx)) | |
1992 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
1993 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
1994 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
1995 | } | |
ca6c03ca | 1996 | |
7b19209f SB |
1997 | if (flags & TDF_DETAILS) |
1998 | df_dump_insn_top (tmp_rtx, outf); | |
a315c44c SB |
1999 | if (! (flags & TDF_SLIM)) |
2000 | print_rtl_single (outf, tmp_rtx); | |
2001 | else | |
2002 | dump_insn_slim (outf, tmp_rtx); | |
7b19209f SB |
2003 | if (flags & TDF_DETAILS) |
2004 | df_dump_insn_bottom (tmp_rtx, outf); | |
ca6c03ca | 2005 | |
c4669594 SB |
2006 | if (flags & TDF_BLOCKS) |
2007 | { | |
2008 | bb = end[INSN_UID (tmp_rtx)]; | |
2009 | if (bb != NULL) | |
2010 | { | |
2011 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true); | |
2012 | if (df && (flags & TDF_DETAILS)) | |
2013 | df_dump_bottom (bb, outf); | |
1b03a96d | 2014 | putc ('\n', outf); |
c4669594 SB |
2015 | } |
2016 | } | |
ca6c03ca JH |
2017 | } |
2018 | ||
2019 | free (start); | |
2020 | free (end); | |
2021 | free (in_bb_p); | |
2022 | } | |
ca6c03ca JH |
2023 | } |
2024 | \f | |
532aafad SB |
2025 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
2026 | ||
b446e5a2 | 2027 | void |
d329e058 | 2028 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
2029 | { |
2030 | rtx note; | |
4b4bf941 | 2031 | if (!JUMP_P (BB_END (bb))) |
b446e5a2 | 2032 | return; |
a813c111 | 2033 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
b446e5a2 JH |
2034 | if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability) |
2035 | return; | |
2036 | XEXP (note, 0) = GEN_INT (BRANCH_EDGE (bb)->probability); | |
2037 | } | |
96370780 MK |
2038 | |
2039 | /* Get the last insn associated with block BB (that includes barriers and | |
2040 | tablejumps after BB). */ | |
2041 | rtx | |
2042 | get_last_bb_insn (basic_block bb) | |
2043 | { | |
2044 | rtx tmp; | |
2045 | rtx end = BB_END (bb); | |
2046 | ||
2047 | /* Include any jump table following the basic block. */ | |
2048 | if (tablejump_p (end, NULL, &tmp)) | |
2049 | end = tmp; | |
2050 | ||
2051 | /* Include any barriers that may follow the basic block. */ | |
1e211590 | 2052 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2053 | while (tmp && BARRIER_P (tmp)) |
2054 | { | |
2055 | end = tmp; | |
1e211590 | 2056 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2057 | } |
2058 | ||
2059 | return end; | |
2060 | } | |
b446e5a2 | 2061 | \f |
10e9fecc JH |
2062 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2063 | cfglayout RTL. | |
ca6c03ca JH |
2064 | |
2065 | Currently it does following checks: | |
2066 | ||
ca6c03ca | 2067 | - overlapping of basic blocks |
9eab6785 | 2068 | - insns with wrong BLOCK_FOR_INSN pointers |
ca6c03ca | 2069 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) |
f63d1bf7 | 2070 | - tails of basic blocks (ensure that boundary is necessary) |
ca6c03ca JH |
2071 | - scans body of the basic block for JUMP_INSN, CODE_LABEL |
2072 | and NOTE_INSN_BASIC_BLOCK | |
750054a2 | 2073 | - verify that no fall_thru edge crosses hot/cold partition boundaries |
9eab6785 | 2074 | - verify that there are no pending RTL branch predictions |
ca6c03ca JH |
2075 | |
2076 | In future it can be extended check a lot of other stuff as well | |
2077 | (reachability of basic blocks, life information, etc. etc.). */ | |
f470c378 | 2078 | |
10e9fecc | 2079 | static int |
d329e058 | 2080 | rtl_verify_flow_info_1 (void) |
ca6c03ca | 2081 | { |
ca6c03ca | 2082 | rtx x; |
10e9fecc | 2083 | int err = 0; |
94eb5ddb | 2084 | basic_block bb; |
ca6c03ca | 2085 | |
9eab6785 | 2086 | /* Check the general integrity of the basic blocks. */ |
e0082a72 | 2087 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2088 | { |
9eab6785 | 2089 | rtx insn; |
5f0d2358 | 2090 | |
5e2d947c JH |
2091 | if (!(bb->flags & BB_RTL)) |
2092 | { | |
2093 | error ("BB_RTL flag not set for block %d", bb->index); | |
2094 | err = 1; | |
2095 | } | |
2096 | ||
9eab6785 | 2097 | FOR_BB_INSNS (bb, insn) |
8ce9fd5d | 2098 | if (BLOCK_FOR_INSN (insn) != bb) |
9eab6785 SB |
2099 | { |
2100 | error ("insn %d basic block pointer is %d, should be %d", | |
2101 | INSN_UID (insn), | |
2102 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2103 | bb->index); | |
2104 | err = 1; | |
2105 | } | |
a7b87f73 | 2106 | |
bcc708fc | 2107 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2108 | if (!BARRIER_P (insn) |
2109 | && BLOCK_FOR_INSN (insn) != NULL) | |
2110 | { | |
2111 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2112 | INSN_UID (insn), bb->index); | |
2113 | err = 1; | |
2114 | } | |
bcc708fc | 2115 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2116 | if (!BARRIER_P (insn) |
2117 | && BLOCK_FOR_INSN (insn) != NULL) | |
2118 | { | |
2119 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2120 | INSN_UID (insn), bb->index); | |
2121 | err = 1; | |
2122 | } | |
ca6c03ca JH |
2123 | } |
2124 | ||
2125 | /* Now check the basic blocks (boundaries etc.) */ | |
e0082a72 | 2126 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2127 | { |
f99ffaa3 EB |
2128 | int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0; |
2129 | int n_eh = 0, n_abnormal = 0; | |
3cf54412 | 2130 | edge e, fallthru = NULL; |
5a1a3e5e | 2131 | rtx note; |
628f6a4e | 2132 | edge_iterator ei; |
ca6c03ca | 2133 | |
2085a21f | 2134 | if (JUMP_P (BB_END (bb)) |
a813c111 | 2135 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 2136 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 2137 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 2138 | { |
e53de54d JH |
2139 | if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability |
2140 | && profile_status != PROFILE_ABSENT) | |
5a1a3e5e | 2141 | { |
0108ae51 | 2142 | error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i", |
5a1a3e5e JH |
2143 | INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability); |
2144 | err = 1; | |
2145 | } | |
2146 | } | |
628f6a4e | 2147 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 2148 | { |
0be7e7a6 RH |
2149 | bool is_crossing; |
2150 | ||
ca6c03ca | 2151 | if (e->flags & EDGE_FALLTHRU) |
0be7e7a6 RH |
2152 | n_fallthru++, fallthru = e; |
2153 | ||
2154 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
2155 | && e->src != ENTRY_BLOCK_PTR | |
2156 | && e->dest != EXIT_BLOCK_PTR); | |
2157 | if (e->flags & EDGE_CROSSING) | |
750054a2 | 2158 | { |
0be7e7a6 RH |
2159 | if (!is_crossing) |
2160 | { | |
2161 | error ("EDGE_CROSSING incorrectly set across same section"); | |
2162 | err = 1; | |
2163 | } | |
2164 | if (e->flags & EDGE_FALLTHRU) | |
2165 | { | |
f99ffaa3 | 2166 | error ("fallthru edge crosses section boundary in bb %i", |
750054a2 CT |
2167 | e->src->index); |
2168 | err = 1; | |
2169 | } | |
0be7e7a6 RH |
2170 | if (e->flags & EDGE_EH) |
2171 | { | |
f99ffaa3 | 2172 | error ("EH edge crosses section boundary in bb %i", |
0be7e7a6 RH |
2173 | e->src->index); |
2174 | err = 1; | |
2175 | } | |
2176 | } | |
2177 | else if (is_crossing) | |
2178 | { | |
2179 | error ("EDGE_CROSSING missing across section boundary"); | |
2180 | err = 1; | |
750054a2 | 2181 | } |
3dec4024 | 2182 | |
65f43cdf ZD |
2183 | if ((e->flags & ~(EDGE_DFS_BACK |
2184 | | EDGE_CAN_FALLTHRU | |
2185 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 | 2186 | | EDGE_LOOP_EXIT |
7e872b90 JJ |
2187 | | EDGE_CROSSING |
2188 | | EDGE_PRESERVE)) == 0) | |
3dec4024 JH |
2189 | n_branch++; |
2190 | ||
2191 | if (e->flags & EDGE_ABNORMAL_CALL) | |
f99ffaa3 EB |
2192 | n_abnormal_call++; |
2193 | ||
2194 | if (e->flags & EDGE_SIBCALL) | |
2195 | n_sibcall++; | |
3dec4024 JH |
2196 | |
2197 | if (e->flags & EDGE_EH) | |
2198 | n_eh++; | |
f99ffaa3 EB |
2199 | |
2200 | if (e->flags & EDGE_ABNORMAL) | |
3dec4024 | 2201 | n_abnormal++; |
ca6c03ca | 2202 | } |
5f0d2358 | 2203 | |
1d65f45c | 2204 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
3dec4024 | 2205 | { |
f99ffaa3 | 2206 | error ("missing REG_EH_REGION note at the end of bb %i", bb->index); |
3dec4024 JH |
2207 | err = 1; |
2208 | } | |
1d65f45c RH |
2209 | if (n_eh > 1) |
2210 | { | |
f99ffaa3 | 2211 | error ("too many exception handling edges in bb %i", bb->index); |
1d65f45c RH |
2212 | err = 1; |
2213 | } | |
3dec4024 | 2214 | if (n_branch |
4b4bf941 | 2215 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2216 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2217 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2218 | { |
ab532386 | 2219 | error ("too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
2220 | err = 1; |
2221 | } | |
a813c111 | 2222 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2223 | { |
f99ffaa3 | 2224 | error ("fallthru edge after unconditional jump in bb %i", bb->index); |
3dec4024 JH |
2225 | err = 1; |
2226 | } | |
a813c111 | 2227 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2228 | { |
f99ffaa3 EB |
2229 | error ("wrong number of branch edges after unconditional jump" |
2230 | " in bb %i", bb->index); | |
3dec4024 JH |
2231 | err = 1; |
2232 | } | |
a813c111 | 2233 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 2234 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 2235 | { |
f99ffaa3 EB |
2236 | error ("wrong amount of branch edges after conditional jump" |
2237 | " in bb %i", bb->index); | |
2238 | err = 1; | |
2239 | } | |
2240 | if (n_abnormal_call && !CALL_P (BB_END (bb))) | |
2241 | { | |
2242 | error ("abnormal call edges for non-call insn in bb %i", bb->index); | |
3dec4024 JH |
2243 | err = 1; |
2244 | } | |
f99ffaa3 | 2245 | if (n_sibcall && !CALL_P (BB_END (bb))) |
3dec4024 | 2246 | { |
f99ffaa3 | 2247 | error ("sibcall edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
2248 | err = 1; |
2249 | } | |
f99ffaa3 EB |
2250 | if (n_abnormal > n_eh |
2251 | && !(CALL_P (BB_END (bb)) | |
2252 | && n_abnormal == n_abnormal_call + n_sibcall) | |
4b4bf941 | 2253 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2254 | || any_condjump_p (BB_END (bb)) |
2255 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2256 | { |
ab532386 | 2257 | error ("abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
2258 | err = 1; |
2259 | } | |
f87c27b4 | 2260 | |
a813c111 | 2261 | for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x)) |
0ca541aa | 2262 | /* We may have a barrier inside a basic block before dead code |
9524880c HPN |
2263 | elimination. There is no BLOCK_FOR_INSN field in a barrier. */ |
2264 | if (!BARRIER_P (x) && BLOCK_FOR_INSN (x) != bb) | |
5f0d2358 RK |
2265 | { |
2266 | debug_rtx (x); | |
2267 | if (! BLOCK_FOR_INSN (x)) | |
2268 | error | |
2269 | ("insn %d inside basic block %d but block_for_insn is NULL", | |
0b17ab2f | 2270 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2271 | else |
2272 | error | |
2273 | ("insn %d inside basic block %d but block_for_insn is %i", | |
0b17ab2f | 2274 | INSN_UID (x), bb->index, BLOCK_FOR_INSN (x)->index); |
5f0d2358 RK |
2275 | |
2276 | err = 1; | |
2277 | } | |
ca6c03ca JH |
2278 | |
2279 | /* OK pointers are correct. Now check the header of basic | |
c22cacf3 | 2280 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 2281 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 2282 | x = BB_HEAD (bb); |
4b4bf941 | 2283 | if (LABEL_P (x)) |
ca6c03ca | 2284 | { |
a813c111 | 2285 | if (BB_END (bb) == x) |
ca6c03ca JH |
2286 | { |
2287 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2288 | bb->index); |
ca6c03ca JH |
2289 | err = 1; |
2290 | } | |
5f0d2358 | 2291 | |
ca6c03ca JH |
2292 | x = NEXT_INSN (x); |
2293 | } | |
5f0d2358 | 2294 | |
ca6c03ca JH |
2295 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2296 | { | |
2297 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2298 | bb->index); |
ca6c03ca JH |
2299 | err = 1; |
2300 | } | |
2301 | ||
a813c111 | 2302 | if (BB_END (bb) == x) |
49243025 | 2303 | /* Do checks for empty blocks here. */ |
5f0d2358 | 2304 | ; |
ca6c03ca | 2305 | else |
5f0d2358 RK |
2306 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2307 | { | |
2308 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2309 | { | |
2310 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2311 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2312 | err = 1; |
2313 | } | |
2314 | ||
a813c111 | 2315 | if (x == BB_END (bb)) |
5f0d2358 | 2316 | break; |
ca6c03ca | 2317 | |
83fd323c | 2318 | if (control_flow_insn_p (x)) |
5f0d2358 | 2319 | { |
0b17ab2f | 2320 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2321 | fatal_insn ("flow control insn inside a basic block", x); |
2322 | } | |
2323 | } | |
ca6c03ca JH |
2324 | } |
2325 | ||
10e9fecc | 2326 | /* Clean up. */ |
10e9fecc JH |
2327 | return err; |
2328 | } | |
5f0d2358 | 2329 | |
10e9fecc JH |
2330 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2331 | cfglayout RTL. | |
5f0d2358 | 2332 | |
10e9fecc JH |
2333 | Currently it does following checks: |
2334 | - all checks of rtl_verify_flow_info_1 | |
9eab6785 | 2335 | - test head/end pointers |
10e9fecc JH |
2336 | - check that all insns are in the basic blocks |
2337 | (except the switch handling code, barriers and notes) | |
2338 | - check that all returns are followed by barriers | |
2339 | - check that all fallthru edge points to the adjacent blocks. */ | |
9eab6785 | 2340 | |
10e9fecc | 2341 | static int |
d329e058 | 2342 | rtl_verify_flow_info (void) |
10e9fecc JH |
2343 | { |
2344 | basic_block bb; | |
2345 | int err = rtl_verify_flow_info_1 (); | |
2346 | rtx x; | |
9eab6785 SB |
2347 | rtx last_head = get_last_insn (); |
2348 | basic_block *bb_info; | |
10e9fecc JH |
2349 | int num_bb_notes; |
2350 | const rtx rtx_first = get_insns (); | |
2351 | basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL; | |
9eab6785 SB |
2352 | const int max_uid = get_max_uid (); |
2353 | ||
2354 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 2355 | |
10e9fecc JH |
2356 | FOR_EACH_BB_REVERSE (bb) |
2357 | { | |
2358 | edge e; | |
9eab6785 SB |
2359 | rtx head = BB_HEAD (bb); |
2360 | rtx end = BB_END (bb); | |
628f6a4e | 2361 | |
9eab6785 | 2362 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
a7b87f73 ZD |
2363 | { |
2364 | /* Verify the end of the basic block is in the INSN chain. */ | |
2365 | if (x == end) | |
2366 | break; | |
2367 | ||
2368 | /* And that the code outside of basic blocks has NULL bb field. */ | |
2369 | if (!BARRIER_P (x) | |
2370 | && BLOCK_FOR_INSN (x) != NULL) | |
2371 | { | |
2372 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2373 | INSN_UID (x)); | |
2374 | err = 1; | |
2375 | } | |
2376 | } | |
9eab6785 SB |
2377 | |
2378 | if (!x) | |
2379 | { | |
2380 | error ("end insn %d for block %d not found in the insn stream", | |
2381 | INSN_UID (end), bb->index); | |
2382 | err = 1; | |
2383 | } | |
2384 | ||
2385 | /* Work backwards from the end to the head of the basic block | |
2386 | to verify the head is in the RTL chain. */ | |
2387 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 2388 | { |
9eab6785 SB |
2389 | /* While walking over the insn chain, verify insns appear |
2390 | in only one basic block. */ | |
2391 | if (bb_info[INSN_UID (x)] != NULL) | |
2392 | { | |
2393 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2394 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
2395 | err = 1; | |
2396 | } | |
2397 | ||
2398 | bb_info[INSN_UID (x)] = bb; | |
2399 | ||
2400 | if (x == head) | |
2401 | break; | |
2402 | } | |
2403 | if (!x) | |
2404 | { | |
2405 | error ("head insn %d for block %d not found in the insn stream", | |
2406 | INSN_UID (head), bb->index); | |
a00d11f0 JH |
2407 | err = 1; |
2408 | } | |
2409 | ||
a7b87f73 | 2410 | last_head = PREV_INSN (x); |
9eab6785 | 2411 | |
0fd4b31d | 2412 | e = find_fallthru_edge (bb->succs); |
10e9fecc JH |
2413 | if (!e) |
2414 | { | |
2415 | rtx insn; | |
2416 | ||
2417 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
468059bc DD |
2418 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
2419 | { | |
2420 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
10e9fecc JH |
2421 | { |
2422 | error ("missing barrier after block %i", bb->index); | |
2423 | err = 1; | |
2424 | break; | |
2425 | } | |
468059bc DD |
2426 | if (BARRIER_P (insn)) |
2427 | break; | |
2428 | } | |
10e9fecc JH |
2429 | } |
2430 | else if (e->src != ENTRY_BLOCK_PTR | |
2431 | && e->dest != EXIT_BLOCK_PTR) | |
c22cacf3 | 2432 | { |
10e9fecc JH |
2433 | rtx insn; |
2434 | ||
2435 | if (e->src->next_bb != e->dest) | |
2436 | { | |
2437 | error | |
2438 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2439 | e->src->index, e->dest->index); | |
2440 | err = 1; | |
2441 | } | |
2442 | else | |
a813c111 | 2443 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 2444 | insn = NEXT_INSN (insn)) |
6be85b25 | 2445 | if (BARRIER_P (insn) || INSN_P (insn)) |
10e9fecc JH |
2446 | { |
2447 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2448 | e->src->index, e->dest->index); | |
2449 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2450 | err = 1; | |
2451 | } | |
c22cacf3 | 2452 | } |
10e9fecc | 2453 | } |
ca6c03ca | 2454 | |
a7b87f73 ZD |
2455 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
2456 | { | |
2457 | /* Check that the code before the first basic block has NULL | |
2458 | bb field. */ | |
2459 | if (!BARRIER_P (x) | |
2460 | && BLOCK_FOR_INSN (x) != NULL) | |
2461 | { | |
2462 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2463 | INSN_UID (x)); | |
2464 | err = 1; | |
2465 | } | |
2466 | } | |
9eab6785 SB |
2467 | free (bb_info); |
2468 | ||
ca6c03ca | 2469 | num_bb_notes = 0; |
e0082a72 ZD |
2470 | last_bb_seen = ENTRY_BLOCK_PTR; |
2471 | ||
5f0d2358 | 2472 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2473 | { |
2474 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2475 | { | |
bf77398c | 2476 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2477 | |
ca6c03ca | 2478 | num_bb_notes++; |
e0082a72 | 2479 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2480 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2481 | |
10e9fecc | 2482 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2483 | } |
2484 | ||
10e9fecc | 2485 | if (!curr_bb) |
ca6c03ca JH |
2486 | { |
2487 | switch (GET_CODE (x)) | |
2488 | { | |
2489 | case BARRIER: | |
2490 | case NOTE: | |
2491 | break; | |
2492 | ||
2493 | case CODE_LABEL: | |
39718607 | 2494 | /* An ADDR_VEC is placed outside any basic block. */ |
ca6c03ca | 2495 | if (NEXT_INSN (x) |
481683e1 | 2496 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5f0d2358 | 2497 | x = NEXT_INSN (x); |
ca6c03ca JH |
2498 | |
2499 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2500 | break; | |
2501 | ||
2502 | default: | |
1f978f5f | 2503 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2504 | } |
2505 | } | |
2506 | ||
26cae194 | 2507 | if (JUMP_P (x) |
ca6c03ca | 2508 | && returnjump_p (x) && ! condjump_p (x) |
15eb3a2e | 2509 | && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x)))) |
1f978f5f | 2510 | fatal_insn ("return not followed by barrier", x); |
a813c111 | 2511 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2512 | curr_bb = NULL; |
ca6c03ca JH |
2513 | } |
2514 | ||
24bd1a0b | 2515 | if (num_bb_notes != n_basic_blocks - NUM_FIXED_BLOCKS) |
ca6c03ca | 2516 | internal_error |
0b17ab2f RH |
2517 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
2518 | num_bb_notes, n_basic_blocks); | |
ca6c03ca | 2519 | |
10e9fecc | 2520 | return err; |
ca6c03ca JH |
2521 | } |
2522 | \f | |
eaec9b3d | 2523 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2524 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2525 | Return true if any edges are eliminated. */ | |
2526 | ||
2527 | bool | |
d329e058 | 2528 | purge_dead_edges (basic_block bb) |
ca6c03ca | 2529 | { |
628f6a4e | 2530 | edge e; |
a813c111 | 2531 | rtx insn = BB_END (bb), note; |
ca6c03ca | 2532 | bool purged = false; |
628f6a4e BE |
2533 | bool found; |
2534 | edge_iterator ei; | |
ca6c03ca | 2535 | |
b5b8b0ac AO |
2536 | if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) |
2537 | do | |
2538 | insn = PREV_INSN (insn); | |
2539 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
2540 | ||
70da1d03 | 2541 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 2542 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
2543 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2544 | { | |
2545 | rtx eqnote; | |
2546 | ||
2547 | if (! may_trap_p (PATTERN (insn)) | |
2548 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2549 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
2550 | remove_note (insn, note); | |
2551 | } | |
2552 | ||
546c093e | 2553 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 2554 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 2555 | { |
1d65f45c RH |
2556 | bool remove = false; |
2557 | ||
e5f9a909 JW |
2558 | /* There are three types of edges we need to handle correctly here: EH |
2559 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
2560 | latter can appear when nonlocal gotos are used. */ | |
1d65f45c | 2561 | if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 2562 | { |
1d65f45c RH |
2563 | if (!CALL_P (insn)) |
2564 | remove = true; | |
2565 | else if (can_nonlocal_goto (insn)) | |
2566 | ; | |
2567 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
2568 | ; | |
0a35513e AH |
2569 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
2570 | ; | |
1d65f45c RH |
2571 | else |
2572 | remove = true; | |
546c093e | 2573 | } |
1d65f45c RH |
2574 | else if (e->flags & EDGE_EH) |
2575 | remove = !can_throw_internal (insn); | |
2576 | ||
2577 | if (remove) | |
546c093e | 2578 | { |
1d65f45c RH |
2579 | remove_edge (e); |
2580 | df_set_bb_dirty (bb); | |
2581 | purged = true; | |
546c093e RH |
2582 | } |
2583 | else | |
1d65f45c | 2584 | ei_next (&ei); |
546c093e | 2585 | } |
5f0d2358 | 2586 | |
4b4bf941 | 2587 | if (JUMP_P (insn)) |
ca6c03ca JH |
2588 | { |
2589 | rtx note; | |
2590 | edge b,f; | |
628f6a4e | 2591 | edge_iterator ei; |
5f0d2358 | 2592 | |
ca6c03ca JH |
2593 | /* We do care only about conditional jumps and simplejumps. */ |
2594 | if (!any_condjump_p (insn) | |
2595 | && !returnjump_p (insn) | |
2596 | && !simplejump_p (insn)) | |
c51d95ec | 2597 | return purged; |
5f0d2358 | 2598 | |
5a1a3e5e JH |
2599 | /* Branch probability/prediction notes are defined only for |
2600 | condjumps. We've possibly turned condjump into simplejump. */ | |
2601 | if (simplejump_p (insn)) | |
2602 | { | |
2603 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2604 | if (note) | |
2605 | remove_note (insn, note); | |
2606 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
2607 | remove_note (insn, note); | |
2608 | } | |
2609 | ||
628f6a4e | 2610 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2611 | { |
7fcd7218 JH |
2612 | /* Avoid abnormal flags to leak from computed jumps turned |
2613 | into simplejumps. */ | |
f87c27b4 | 2614 | |
0e1638d4 | 2615 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 2616 | |
5a566bed MM |
2617 | /* See if this edge is one we should keep. */ |
2618 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
2619 | /* A conditional jump can fall through into the next | |
2620 | block, so we should keep the edge. */ | |
628f6a4e BE |
2621 | { |
2622 | ei_next (&ei); | |
2623 | continue; | |
2624 | } | |
5f0d2358 | 2625 | else if (e->dest != EXIT_BLOCK_PTR |
a813c111 | 2626 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
2627 | /* If the destination block is the target of the jump, |
2628 | keep the edge. */ | |
628f6a4e BE |
2629 | { |
2630 | ei_next (&ei); | |
2631 | continue; | |
2632 | } | |
5a566bed MM |
2633 | else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn)) |
2634 | /* If the destination block is the exit block, and this | |
2635 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
2636 | { |
2637 | ei_next (&ei); | |
2638 | continue; | |
2639 | } | |
5a566bed MM |
2640 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
2641 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
2642 | this instruction and rematerialize the EDGE_ABNORMAL |
2643 | flag we just cleared above. */ | |
2644 | { | |
2645 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 2646 | ei_next (&ei); |
0b75beaa EB |
2647 | continue; |
2648 | } | |
5f0d2358 | 2649 | |
5a566bed | 2650 | /* We do not need this edge. */ |
6fb5fa3c | 2651 | df_set_bb_dirty (bb); |
ca6c03ca JH |
2652 | purged = true; |
2653 | remove_edge (e); | |
2654 | } | |
5f0d2358 | 2655 | |
628f6a4e | 2656 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 2657 | return purged; |
5f0d2358 | 2658 | |
c263766c RH |
2659 | if (dump_file) |
2660 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 2661 | |
ca6c03ca JH |
2662 | if (!optimize) |
2663 | return purged; | |
2664 | ||
2665 | /* Redistribute probabilities. */ | |
c5cbcccf | 2666 | if (single_succ_p (bb)) |
ca6c03ca | 2667 | { |
c5cbcccf ZD |
2668 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2669 | single_succ_edge (bb)->count = bb->count; | |
f87c27b4 | 2670 | } |
ca6c03ca JH |
2671 | else |
2672 | { | |
2673 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2674 | if (!note) | |
2675 | return purged; | |
5f0d2358 | 2676 | |
ca6c03ca JH |
2677 | b = BRANCH_EDGE (bb); |
2678 | f = FALLTHRU_EDGE (bb); | |
2679 | b->probability = INTVAL (XEXP (note, 0)); | |
2680 | f->probability = REG_BR_PROB_BASE - b->probability; | |
8ddb5a29 | 2681 | /* Update these to use GCOV_COMPUTE_SCALE. */ |
ca6c03ca JH |
2682 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; |
2683 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
2684 | } | |
5f0d2358 | 2685 | |
ca6c03ca JH |
2686 | return purged; |
2687 | } | |
4b4bf941 | 2688 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
2689 | { |
2690 | /* First, there should not be any EH or ABCALL edges resulting | |
2691 | from non-local gotos and the like. If there were, we shouldn't | |
2692 | have created the sibcall in the first place. Second, there | |
2693 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
2694 | gcc_assert (single_succ_p (bb)); |
2695 | gcc_assert (single_succ_edge (bb)->flags | |
2696 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 RH |
2697 | |
2698 | return 0; | |
2699 | } | |
ca6c03ca | 2700 | |
ca6c03ca JH |
2701 | /* If we don't see a jump insn, we don't know exactly why the block would |
2702 | have been broken at this point. Look for a simple, non-fallthru edge, | |
2703 | as these are only created by conditional branches. If we find such an | |
2704 | edge we know that there used to be a jump here and can then safely | |
2705 | remove all non-fallthru edges. */ | |
628f6a4e BE |
2706 | found = false; |
2707 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2708 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
2709 | { | |
2710 | found = true; | |
2711 | break; | |
2712 | } | |
5f0d2358 | 2713 | |
628f6a4e | 2714 | if (!found) |
ca6c03ca | 2715 | return purged; |
5f0d2358 | 2716 | |
2afa8dce DB |
2717 | /* Remove all but the fake and fallthru edges. The fake edge may be |
2718 | the only successor for this block in the case of noreturn | |
2719 | calls. */ | |
628f6a4e | 2720 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2721 | { |
2afa8dce | 2722 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec | 2723 | { |
6fb5fa3c | 2724 | df_set_bb_dirty (bb); |
c51d95ec JH |
2725 | remove_edge (e); |
2726 | purged = true; | |
2727 | } | |
628f6a4e BE |
2728 | else |
2729 | ei_next (&ei); | |
ca6c03ca | 2730 | } |
5f0d2358 | 2731 | |
c5cbcccf | 2732 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 2733 | |
c5cbcccf ZD |
2734 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2735 | single_succ_edge (bb)->count = bb->count; | |
ca6c03ca | 2736 | |
c263766c RH |
2737 | if (dump_file) |
2738 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 2739 | bb->index); |
ca6c03ca JH |
2740 | return purged; |
2741 | } | |
2742 | ||
5f0d2358 RK |
2743 | /* Search all basic blocks for potentially dead edges and purge them. Return |
2744 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
2745 | |
2746 | bool | |
25cd19de | 2747 | purge_all_dead_edges (void) |
ca6c03ca | 2748 | { |
e0082a72 | 2749 | int purged = false; |
e0082a72 | 2750 | basic_block bb; |
473fb060 | 2751 | |
e0082a72 | 2752 | FOR_EACH_BB (bb) |
473fb060 | 2753 | { |
e0082a72 | 2754 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 2755 | |
473fb060 | 2756 | purged |= purged_here; |
473fb060 | 2757 | } |
5f0d2358 | 2758 | |
ca6c03ca JH |
2759 | return purged; |
2760 | } | |
9ee634e3 | 2761 | |
ba5e9aca EB |
2762 | /* This is used by a few passes that emit some instructions after abnormal |
2763 | calls, moving the basic block's end, while they in fact do want to emit | |
2764 | them on the fallthru edge. Look for abnormal call edges, find backward | |
2765 | the call in the block and insert the instructions on the edge instead. | |
2766 | ||
2767 | Similarly, handle instructions throwing exceptions internally. | |
2768 | ||
2769 | Return true when instructions have been found and inserted on edges. */ | |
2770 | ||
2771 | bool | |
2772 | fixup_abnormal_edges (void) | |
2773 | { | |
2774 | bool inserted = false; | |
2775 | basic_block bb; | |
2776 | ||
2777 | FOR_EACH_BB (bb) | |
2778 | { | |
2779 | edge e; | |
2780 | edge_iterator ei; | |
2781 | ||
2782 | /* Look for cases we are interested in - calls or instructions causing | |
2783 | exceptions. */ | |
2784 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2785 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
2786 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
2787 | == (EDGE_ABNORMAL | EDGE_EH))) | |
2788 | break; | |
2789 | ||
2790 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
2791 | { | |
2792 | rtx insn; | |
2793 | ||
2794 | /* Get past the new insns generated. Allow notes, as the insns | |
2795 | may be already deleted. */ | |
2796 | insn = BB_END (bb); | |
2797 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
2798 | && !can_throw_internal (insn) | |
2799 | && insn != BB_HEAD (bb)) | |
2800 | insn = PREV_INSN (insn); | |
2801 | ||
2802 | if (CALL_P (insn) || can_throw_internal (insn)) | |
2803 | { | |
2804 | rtx stop, next; | |
2805 | ||
2806 | e = find_fallthru_edge (bb->succs); | |
2807 | ||
2808 | stop = NEXT_INSN (BB_END (bb)); | |
2809 | BB_END (bb) = insn; | |
2810 | ||
2811 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
2812 | { | |
2813 | next = NEXT_INSN (insn); | |
2814 | if (INSN_P (insn)) | |
2815 | { | |
2816 | delete_insn (insn); | |
2817 | ||
2818 | /* Sometimes there's still the return value USE. | |
2819 | If it's placed after a trapping call (i.e. that | |
2820 | call is the last insn anyway), we have no fallthru | |
2821 | edge. Simply delete this use and don't try to insert | |
2822 | on the non-existent edge. */ | |
2823 | if (GET_CODE (PATTERN (insn)) != USE) | |
2824 | { | |
2825 | /* We're not deleting it, we're moving it. */ | |
2826 | INSN_DELETED_P (insn) = 0; | |
2827 | PREV_INSN (insn) = NULL_RTX; | |
2828 | NEXT_INSN (insn) = NULL_RTX; | |
2829 | ||
2830 | insert_insn_on_edge (insn, e); | |
2831 | inserted = true; | |
2832 | } | |
2833 | } | |
2834 | else if (!BARRIER_P (insn)) | |
2835 | set_block_for_insn (insn, NULL); | |
2836 | } | |
2837 | } | |
2838 | ||
2839 | /* It may be that we don't find any trapping insn. In this | |
2840 | case we discovered quite late that the insn that had been | |
2841 | marked as can_throw_internal in fact couldn't trap at all. | |
2842 | So we should in fact delete the EH edges out of the block. */ | |
2843 | else | |
2844 | purge_dead_edges (bb); | |
2845 | } | |
2846 | } | |
2847 | ||
2848 | return inserted; | |
2849 | } | |
78bde837 SB |
2850 | \f |
2851 | /* Cut the insns from FIRST to LAST out of the insns stream. */ | |
2852 | ||
2853 | rtx | |
2854 | unlink_insn_chain (rtx first, rtx last) | |
2855 | { | |
2856 | rtx prevfirst = PREV_INSN (first); | |
2857 | rtx nextlast = NEXT_INSN (last); | |
2858 | ||
2859 | PREV_INSN (first) = NULL; | |
2860 | NEXT_INSN (last) = NULL; | |
2861 | if (prevfirst) | |
2862 | NEXT_INSN (prevfirst) = nextlast; | |
2863 | if (nextlast) | |
2864 | PREV_INSN (nextlast) = prevfirst; | |
2865 | else | |
2866 | set_last_insn (prevfirst); | |
2867 | if (!prevfirst) | |
2868 | set_first_insn (nextlast); | |
2869 | return first; | |
2870 | } | |
2871 | \f | |
2872 | /* Skip over inter-block insns occurring after BB which are typically | |
2873 | associated with BB (e.g., barriers). If there are any such insns, | |
2874 | we return the last one. Otherwise, we return the end of BB. */ | |
2875 | ||
2876 | static rtx | |
2877 | skip_insns_after_block (basic_block bb) | |
2878 | { | |
2879 | rtx insn, last_insn, next_head, prev; | |
2880 | ||
2881 | next_head = NULL_RTX; | |
2882 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
2883 | next_head = BB_HEAD (bb->next_bb); | |
2884 | ||
2885 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
2886 | { | |
2887 | if (insn == next_head) | |
2888 | break; | |
2889 | ||
2890 | switch (GET_CODE (insn)) | |
2891 | { | |
2892 | case BARRIER: | |
2893 | last_insn = insn; | |
2894 | continue; | |
2895 | ||
2896 | case NOTE: | |
2897 | switch (NOTE_KIND (insn)) | |
2898 | { | |
2899 | case NOTE_INSN_BLOCK_END: | |
2900 | gcc_unreachable (); | |
2901 | continue; | |
2902 | default: | |
2903 | continue; | |
2904 | break; | |
2905 | } | |
2906 | break; | |
2907 | ||
2908 | case CODE_LABEL: | |
2909 | if (NEXT_INSN (insn) | |
2910 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
2911 | { | |
2912 | insn = NEXT_INSN (insn); | |
2913 | last_insn = insn; | |
2914 | continue; | |
2915 | } | |
2916 | break; | |
2917 | ||
2918 | default: | |
2919 | break; | |
2920 | } | |
2921 | ||
2922 | break; | |
2923 | } | |
2924 | ||
2925 | /* It is possible to hit contradictory sequence. For instance: | |
2926 | ||
2927 | jump_insn | |
2928 | NOTE_INSN_BLOCK_BEG | |
2929 | barrier | |
2930 | ||
2931 | Where barrier belongs to jump_insn, but the note does not. This can be | |
2932 | created by removing the basic block originally following | |
2933 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
2934 | ||
2935 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
2936 | { | |
2937 | prev = PREV_INSN (insn); | |
2938 | if (NOTE_P (insn)) | |
2939 | switch (NOTE_KIND (insn)) | |
2940 | { | |
2941 | case NOTE_INSN_BLOCK_END: | |
2942 | gcc_unreachable (); | |
2943 | break; | |
2944 | case NOTE_INSN_DELETED: | |
2945 | case NOTE_INSN_DELETED_LABEL: | |
2946 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
2947 | continue; | |
2948 | default: | |
2949 | reorder_insns (insn, insn, last_insn); | |
2950 | } | |
2951 | } | |
2952 | ||
2953 | return last_insn; | |
2954 | } | |
2955 | ||
2956 | /* Locate or create a label for a given basic block. */ | |
2957 | ||
2958 | static rtx | |
2959 | label_for_bb (basic_block bb) | |
2960 | { | |
2961 | rtx label = BB_HEAD (bb); | |
2962 | ||
2963 | if (!LABEL_P (label)) | |
2964 | { | |
2965 | if (dump_file) | |
2966 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
2967 | ||
2968 | label = block_label (bb); | |
2969 | } | |
2970 | ||
2971 | return label; | |
2972 | } | |
2973 | ||
2974 | /* Locate the effective beginning and end of the insn chain for each | |
2975 | block, as defined by skip_insns_after_block above. */ | |
2976 | ||
2977 | static void | |
2978 | record_effective_endpoints (void) | |
2979 | { | |
2980 | rtx next_insn; | |
2981 | basic_block bb; | |
2982 | rtx insn; | |
2983 | ||
2984 | for (insn = get_insns (); | |
2985 | insn | |
2986 | && NOTE_P (insn) | |
2987 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
2988 | insn = NEXT_INSN (insn)) | |
2989 | continue; | |
2990 | /* No basic blocks at all? */ | |
2991 | gcc_assert (insn); | |
2992 | ||
2993 | if (PREV_INSN (insn)) | |
2994 | cfg_layout_function_header = | |
2995 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
2996 | else | |
2997 | cfg_layout_function_header = NULL_RTX; | |
2998 | ||
2999 | next_insn = get_insns (); | |
3000 | FOR_EACH_BB (bb) | |
3001 | { | |
3002 | rtx end; | |
3003 | ||
3004 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
3005 | BB_HEADER (bb) = unlink_insn_chain (next_insn, | |
3006 | PREV_INSN (BB_HEAD (bb))); | |
3007 | end = skip_insns_after_block (bb); | |
3008 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
3009 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); | |
3010 | next_insn = NEXT_INSN (BB_END (bb)); | |
3011 | } | |
3012 | ||
3013 | cfg_layout_function_footer = next_insn; | |
3014 | if (cfg_layout_function_footer) | |
3015 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
3016 | } | |
3017 | \f | |
3018 | static unsigned int | |
3019 | into_cfg_layout_mode (void) | |
3020 | { | |
3021 | cfg_layout_initialize (0); | |
3022 | return 0; | |
3023 | } | |
3024 | ||
3025 | static unsigned int | |
3026 | outof_cfg_layout_mode (void) | |
3027 | { | |
3028 | basic_block bb; | |
3029 | ||
3030 | FOR_EACH_BB (bb) | |
3031 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
3032 | bb->aux = bb->next_bb; | |
3033 | ||
3034 | cfg_layout_finalize (); | |
3035 | ||
3036 | return 0; | |
3037 | } | |
3038 | ||
3039 | struct rtl_opt_pass pass_into_cfg_layout_mode = | |
3040 | { | |
3041 | { | |
3042 | RTL_PASS, | |
3043 | "into_cfglayout", /* name */ | |
2b4e6bf1 | 3044 | OPTGROUP_NONE, /* optinfo_flags */ |
78bde837 SB |
3045 | NULL, /* gate */ |
3046 | into_cfg_layout_mode, /* execute */ | |
3047 | NULL, /* sub */ | |
3048 | NULL, /* next */ | |
3049 | 0, /* static_pass_number */ | |
3050 | TV_CFG, /* tv_id */ | |
3051 | 0, /* properties_required */ | |
3052 | PROP_cfglayout, /* properties_provided */ | |
3053 | 0, /* properties_destroyed */ | |
3054 | 0, /* todo_flags_start */ | |
3055 | 0 /* todo_flags_finish */ | |
3056 | } | |
3057 | }; | |
3058 | ||
3059 | struct rtl_opt_pass pass_outof_cfg_layout_mode = | |
3060 | { | |
3061 | { | |
3062 | RTL_PASS, | |
3063 | "outof_cfglayout", /* name */ | |
2b4e6bf1 | 3064 | OPTGROUP_NONE, /* optinfo_flags */ |
78bde837 SB |
3065 | NULL, /* gate */ |
3066 | outof_cfg_layout_mode, /* execute */ | |
3067 | NULL, /* sub */ | |
3068 | NULL, /* next */ | |
3069 | 0, /* static_pass_number */ | |
3070 | TV_CFG, /* tv_id */ | |
3071 | 0, /* properties_required */ | |
3072 | 0, /* properties_provided */ | |
3073 | PROP_cfglayout, /* properties_destroyed */ | |
3074 | 0, /* todo_flags_start */ | |
3075 | 0 /* todo_flags_finish */ | |
3076 | } | |
3077 | }; | |
3078 | \f | |
3079 | ||
3080 | /* Link the basic blocks in the correct order, compacting the basic | |
3081 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3082 | function also clears the basic block header and footer fields. | |
3083 | ||
3084 | This function is usually called after a pass (e.g. tracer) finishes | |
3085 | some transformations while in cfglayout mode. The required sequence | |
3086 | of the basic blocks is in a linked list along the bb->aux field. | |
3087 | This functions re-links the basic block prev_bb and next_bb pointers | |
532aafad SB |
3088 | accordingly, and it compacts and renumbers the blocks. |
3089 | ||
3090 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3091 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3092 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3093 | chain. It could do that (to give better initial RTL) if this function | |
3094 | is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */ | |
78bde837 SB |
3095 | |
3096 | void | |
3097 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3098 | { | |
3099 | basic_block bb, prev_bb; | |
3100 | int index; | |
3101 | ||
3102 | /* Maybe dump the re-ordered sequence. */ | |
3103 | if (dump_file) | |
3104 | { | |
3105 | fprintf (dump_file, "Reordered sequence:\n"); | |
3106 | for (bb = ENTRY_BLOCK_PTR->next_bb, index = NUM_FIXED_BLOCKS; | |
3107 | bb; | |
3108 | bb = (basic_block) bb->aux, index++) | |
3109 | { | |
3110 | fprintf (dump_file, " %i ", index); | |
3111 | if (get_bb_original (bb)) | |
3112 | fprintf (dump_file, "duplicate of %i ", | |
3113 | get_bb_original (bb)->index); | |
3114 | else if (forwarder_block_p (bb) | |
3115 | && !LABEL_P (BB_HEAD (bb))) | |
3116 | fprintf (dump_file, "compensation "); | |
3117 | else | |
3118 | fprintf (dump_file, "bb %i ", bb->index); | |
3119 | fprintf (dump_file, " [%i]\n", bb->frequency); | |
3120 | } | |
3121 | } | |
3122 | ||
3123 | /* Now reorder the blocks. */ | |
3124 | prev_bb = ENTRY_BLOCK_PTR; | |
3125 | bb = ENTRY_BLOCK_PTR->next_bb; | |
3126 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) | |
3127 | { | |
3128 | bb->prev_bb = prev_bb; | |
3129 | prev_bb->next_bb = bb; | |
3130 | } | |
3131 | prev_bb->next_bb = EXIT_BLOCK_PTR; | |
3132 | EXIT_BLOCK_PTR->prev_bb = prev_bb; | |
3133 | ||
3134 | /* Then, clean up the aux fields. */ | |
3135 | FOR_ALL_BB (bb) | |
3136 | { | |
3137 | bb->aux = NULL; | |
3138 | if (!stay_in_cfglayout_mode) | |
3139 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; | |
3140 | } | |
3141 | ||
3142 | /* Maybe reset the original copy tables, they are not valid anymore | |
3143 | when we renumber the basic blocks in compact_blocks. If we are | |
3144 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
3145 | free_original_copy_tables (); | |
3146 | if (stay_in_cfglayout_mode) | |
3147 | initialize_original_copy_tables (); | |
3148 | ||
3149 | /* Finally, put basic_block_info in the new order. */ | |
3150 | compact_blocks (); | |
3151 | } | |
3152 | \f | |
3153 | ||
3154 | /* Given a reorder chain, rearrange the code to match. */ | |
3155 | ||
3156 | static void | |
3157 | fixup_reorder_chain (void) | |
3158 | { | |
3159 | basic_block bb; | |
3160 | rtx insn = NULL; | |
3161 | ||
3162 | if (cfg_layout_function_header) | |
3163 | { | |
3164 | set_first_insn (cfg_layout_function_header); | |
3165 | insn = cfg_layout_function_header; | |
3166 | while (NEXT_INSN (insn)) | |
3167 | insn = NEXT_INSN (insn); | |
3168 | } | |
3169 | ||
3170 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3171 | the needed changes to jumps and labels. */ | |
3172 | ||
3173 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb; bb = (basic_block) bb->aux) | |
3174 | { | |
3175 | if (BB_HEADER (bb)) | |
3176 | { | |
3177 | if (insn) | |
3178 | NEXT_INSN (insn) = BB_HEADER (bb); | |
3179 | else | |
3180 | set_first_insn (BB_HEADER (bb)); | |
3181 | PREV_INSN (BB_HEADER (bb)) = insn; | |
3182 | insn = BB_HEADER (bb); | |
3183 | while (NEXT_INSN (insn)) | |
3184 | insn = NEXT_INSN (insn); | |
3185 | } | |
3186 | if (insn) | |
3187 | NEXT_INSN (insn) = BB_HEAD (bb); | |
3188 | else | |
3189 | set_first_insn (BB_HEAD (bb)); | |
3190 | PREV_INSN (BB_HEAD (bb)) = insn; | |
3191 | insn = BB_END (bb); | |
3192 | if (BB_FOOTER (bb)) | |
3193 | { | |
3194 | NEXT_INSN (insn) = BB_FOOTER (bb); | |
3195 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
3196 | while (NEXT_INSN (insn)) | |
3197 | insn = NEXT_INSN (insn); | |
3198 | } | |
3199 | } | |
3200 | ||
3201 | NEXT_INSN (insn) = cfg_layout_function_footer; | |
3202 | if (cfg_layout_function_footer) | |
3203 | PREV_INSN (cfg_layout_function_footer) = insn; | |
3204 | ||
3205 | while (NEXT_INSN (insn)) | |
3206 | insn = NEXT_INSN (insn); | |
3207 | ||
3208 | set_last_insn (insn); | |
3209 | #ifdef ENABLE_CHECKING | |
3210 | verify_insn_chain (); | |
3211 | #endif | |
3212 | ||
3213 | /* Now add jumps and labels as needed to match the blocks new | |
3214 | outgoing edges. */ | |
3215 | ||
3216 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb ; bb = (basic_block) bb->aux) | |
3217 | { | |
3218 | edge e_fall, e_taken, e; | |
3219 | rtx bb_end_insn; | |
3220 | rtx ret_label = NULL_RTX; | |
3221 | basic_block nb, src_bb; | |
3222 | edge_iterator ei; | |
3223 | ||
3224 | if (EDGE_COUNT (bb->succs) == 0) | |
3225 | continue; | |
3226 | ||
3227 | /* Find the old fallthru edge, and another non-EH edge for | |
3228 | a taken jump. */ | |
3229 | e_taken = e_fall = NULL; | |
3230 | ||
3231 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3232 | if (e->flags & EDGE_FALLTHRU) | |
3233 | e_fall = e; | |
3234 | else if (! (e->flags & EDGE_EH)) | |
3235 | e_taken = e; | |
3236 | ||
3237 | bb_end_insn = BB_END (bb); | |
3238 | if (JUMP_P (bb_end_insn)) | |
3239 | { | |
3240 | ret_label = JUMP_LABEL (bb_end_insn); | |
3241 | if (any_condjump_p (bb_end_insn)) | |
3242 | { | |
3243 | /* This might happen if the conditional jump has side | |
3244 | effects and could therefore not be optimized away. | |
3245 | Make the basic block to end with a barrier in order | |
3246 | to prevent rtl_verify_flow_info from complaining. */ | |
3247 | if (!e_fall) | |
3248 | { | |
3249 | gcc_assert (!onlyjump_p (bb_end_insn) | |
3250 | || returnjump_p (bb_end_insn)); | |
39718607 | 3251 | emit_barrier_after (bb_end_insn); |
78bde837 SB |
3252 | continue; |
3253 | } | |
3254 | ||
3255 | /* If the old fallthru is still next, nothing to do. */ | |
3256 | if (bb->aux == e_fall->dest | |
3257 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3258 | continue; | |
3259 | ||
3260 | /* The degenerated case of conditional jump jumping to the next | |
3261 | instruction can happen for jumps with side effects. We need | |
3262 | to construct a forwarder block and this will be done just | |
3263 | fine by force_nonfallthru below. */ | |
3264 | if (!e_taken) | |
3265 | ; | |
3266 | ||
3267 | /* There is another special case: if *neither* block is next, | |
3268 | such as happens at the very end of a function, then we'll | |
3269 | need to add a new unconditional jump. Choose the taken | |
3270 | edge based on known or assumed probability. */ | |
3271 | else if (bb->aux != e_taken->dest) | |
3272 | { | |
3273 | rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0); | |
3274 | ||
3275 | if (note | |
3276 | && INTVAL (XEXP (note, 0)) < REG_BR_PROB_BASE / 2 | |
3277 | && invert_jump (bb_end_insn, | |
3278 | (e_fall->dest == EXIT_BLOCK_PTR | |
3279 | ? NULL_RTX | |
3280 | : label_for_bb (e_fall->dest)), 0)) | |
3281 | { | |
3282 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3283 | gcc_checking_assert (could_fall_through | |
3284 | (e_taken->src, e_taken->dest)); | |
3285 | e_taken->flags |= EDGE_FALLTHRU; | |
3286 | update_br_prob_note (bb); | |
3287 | e = e_fall, e_fall = e_taken, e_taken = e; | |
3288 | } | |
3289 | } | |
3290 | ||
3291 | /* If the "jumping" edge is a crossing edge, and the fall | |
3292 | through edge is non-crossing, leave things as they are. */ | |
3293 | else if ((e_taken->flags & EDGE_CROSSING) | |
3294 | && !(e_fall->flags & EDGE_CROSSING)) | |
3295 | continue; | |
3296 | ||
3297 | /* Otherwise we can try to invert the jump. This will | |
3298 | basically never fail, however, keep up the pretense. */ | |
3299 | else if (invert_jump (bb_end_insn, | |
3300 | (e_fall->dest == EXIT_BLOCK_PTR | |
3301 | ? NULL_RTX | |
3302 | : label_for_bb (e_fall->dest)), 0)) | |
3303 | { | |
3304 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3305 | gcc_checking_assert (could_fall_through | |
3306 | (e_taken->src, e_taken->dest)); | |
3307 | e_taken->flags |= EDGE_FALLTHRU; | |
3308 | update_br_prob_note (bb); | |
3309 | if (LABEL_NUSES (ret_label) == 0 | |
3310 | && single_pred_p (e_taken->dest)) | |
3311 | delete_insn (ret_label); | |
3312 | continue; | |
3313 | } | |
3314 | } | |
3315 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
3316 | { | |
3317 | /* If the old fallthru is still next or if | |
3318 | asm goto doesn't have a fallthru (e.g. when followed by | |
3319 | __builtin_unreachable ()), nothing to do. */ | |
3320 | if (! e_fall | |
3321 | || bb->aux == e_fall->dest | |
3322 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3323 | continue; | |
3324 | ||
3325 | /* Otherwise we'll have to use the fallthru fixup below. */ | |
3326 | } | |
3327 | else | |
3328 | { | |
3329 | /* Otherwise we have some return, switch or computed | |
3330 | jump. In the 99% case, there should not have been a | |
3331 | fallthru edge. */ | |
3332 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
3333 | continue; | |
3334 | } | |
3335 | } | |
3336 | else | |
3337 | { | |
3338 | /* No fallthru implies a noreturn function with EH edges, or | |
3339 | something similarly bizarre. In any case, we don't need to | |
3340 | do anything. */ | |
3341 | if (! e_fall) | |
3342 | continue; | |
3343 | ||
3344 | /* If the fallthru block is still next, nothing to do. */ | |
3345 | if (bb->aux == e_fall->dest) | |
3346 | continue; | |
3347 | ||
3348 | /* A fallthru to exit block. */ | |
3349 | if (e_fall->dest == EXIT_BLOCK_PTR) | |
3350 | continue; | |
3351 | } | |
3352 | ||
3353 | /* We got here if we need to add a new jump insn. | |
3354 | Note force_nonfallthru can delete E_FALL and thus we have to | |
3355 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
3356 | src_bb = e_fall->src; | |
3357 | nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label); | |
3358 | if (nb) | |
3359 | { | |
3360 | nb->aux = bb->aux; | |
3361 | bb->aux = nb; | |
3362 | /* Don't process this new block. */ | |
3363 | bb = nb; | |
3364 | ||
3365 | /* Make sure new bb is tagged for correct section (same as | |
3366 | fall-thru source, since you cannot fall-thru across | |
3367 | section boundaries). */ | |
3368 | BB_COPY_PARTITION (src_bb, single_pred (bb)); | |
3369 | if (flag_reorder_blocks_and_partition | |
3370 | && targetm_common.have_named_sections | |
3371 | && JUMP_P (BB_END (bb)) | |
3372 | && !any_condjump_p (BB_END (bb)) | |
3373 | && (EDGE_SUCC (bb, 0)->flags & EDGE_CROSSING)) | |
3374 | add_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX); | |
3375 | } | |
3376 | } | |
3377 | ||
3378 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
3379 | ||
3380 | /* Annoying special case - jump around dead jumptables left in the code. */ | |
3381 | FOR_EACH_BB (bb) | |
3382 | { | |
3383 | edge e = find_fallthru_edge (bb->succs); | |
3384 | ||
3385 | if (e && !can_fallthru (e->src, e->dest)) | |
3386 | force_nonfallthru (e); | |
3387 | } | |
3388 | ||
3389 | /* Ensure goto_locus from edges has some instructions with that locus | |
3390 | in RTL. */ | |
3391 | if (!optimize) | |
3392 | FOR_EACH_BB (bb) | |
3393 | { | |
3394 | edge e; | |
3395 | edge_iterator ei; | |
3396 | ||
3397 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2f13f2de | 3398 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5368224f | 3399 | && !(e->flags & EDGE_ABNORMAL)) |
78bde837 SB |
3400 | { |
3401 | edge e2; | |
3402 | edge_iterator ei2; | |
3403 | basic_block dest, nb; | |
3404 | rtx end; | |
3405 | ||
3406 | insn = BB_END (e->src); | |
3407 | end = PREV_INSN (BB_HEAD (e->src)); | |
3408 | while (insn != end | |
5368224f | 3409 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
78bde837 SB |
3410 | insn = PREV_INSN (insn); |
3411 | if (insn != end | |
5368224f | 3412 | && INSN_LOCATION (insn) == e->goto_locus) |
78bde837 SB |
3413 | continue; |
3414 | if (simplejump_p (BB_END (e->src)) | |
5368224f | 3415 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
78bde837 | 3416 | { |
5368224f | 3417 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
78bde837 SB |
3418 | continue; |
3419 | } | |
3420 | dest = e->dest; | |
3421 | if (dest == EXIT_BLOCK_PTR) | |
3422 | { | |
3423 | /* Non-fallthru edges to the exit block cannot be split. */ | |
3424 | if (!(e->flags & EDGE_FALLTHRU)) | |
3425 | continue; | |
3426 | } | |
3427 | else | |
3428 | { | |
3429 | insn = BB_HEAD (dest); | |
3430 | end = NEXT_INSN (BB_END (dest)); | |
3431 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
3432 | insn = NEXT_INSN (insn); | |
5368224f DC |
3433 | if (insn != end && INSN_HAS_LOCATION (insn) |
3434 | && INSN_LOCATION (insn) == e->goto_locus) | |
78bde837 SB |
3435 | continue; |
3436 | } | |
3437 | nb = split_edge (e); | |
3438 | if (!INSN_P (BB_END (nb))) | |
3439 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), | |
3440 | nb); | |
5368224f | 3441 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
78bde837 SB |
3442 | |
3443 | /* If there are other incoming edges to the destination block | |
3444 | with the same goto locus, redirect them to the new block as | |
3445 | well, this can prevent other such blocks from being created | |
3446 | in subsequent iterations of the loop. */ | |
3447 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
2f13f2de | 3448 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
78bde837 | 3449 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5368224f | 3450 | && e->goto_locus == e2->goto_locus) |
78bde837 SB |
3451 | redirect_edge_and_branch (e2, nb); |
3452 | else | |
3453 | ei_next (&ei2); | |
3454 | } | |
3455 | } | |
3456 | } | |
3457 | \f | |
3458 | /* Perform sanity checks on the insn chain. | |
3459 | 1. Check that next/prev pointers are consistent in both the forward and | |
3460 | reverse direction. | |
3461 | 2. Count insns in chain, going both directions, and check if equal. | |
3462 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
3463 | ||
3464 | DEBUG_FUNCTION void | |
3465 | verify_insn_chain (void) | |
3466 | { | |
3467 | rtx x, prevx, nextx; | |
3468 | int insn_cnt1, insn_cnt2; | |
3469 | ||
3470 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
3471 | x != 0; | |
3472 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
3473 | gcc_assert (PREV_INSN (x) == prevx); | |
3474 | ||
3475 | gcc_assert (prevx == get_last_insn ()); | |
3476 | ||
3477 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
3478 | x != 0; | |
3479 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
3480 | gcc_assert (NEXT_INSN (x) == nextx); | |
3481 | ||
3482 | gcc_assert (insn_cnt1 == insn_cnt2); | |
3483 | } | |
3484 | \f | |
3485 | /* If we have assembler epilogues, the block falling through to exit must | |
3486 | be the last one in the reordered chain when we reach final. Ensure | |
3487 | that this condition is met. */ | |
3488 | static void | |
3489 | fixup_fallthru_exit_predecessor (void) | |
3490 | { | |
3491 | edge e; | |
3492 | basic_block bb = NULL; | |
3493 | ||
3494 | /* This transformation is not valid before reload, because we might | |
3495 | separate a call from the instruction that copies the return | |
3496 | value. */ | |
3497 | gcc_assert (reload_completed); | |
3498 | ||
3499 | e = find_fallthru_edge (EXIT_BLOCK_PTR->preds); | |
3500 | if (e) | |
3501 | bb = e->src; | |
3502 | ||
3503 | if (bb && bb->aux) | |
3504 | { | |
3505 | basic_block c = ENTRY_BLOCK_PTR->next_bb; | |
3506 | ||
3507 | /* If the very first block is the one with the fall-through exit | |
3508 | edge, we have to split that block. */ | |
3509 | if (c == bb) | |
3510 | { | |
3511 | bb = split_block (bb, NULL)->dest; | |
3512 | bb->aux = c->aux; | |
3513 | c->aux = bb; | |
3514 | BB_FOOTER (bb) = BB_FOOTER (c); | |
3515 | BB_FOOTER (c) = NULL; | |
3516 | } | |
3517 | ||
3518 | while (c->aux != bb) | |
3519 | c = (basic_block) c->aux; | |
3520 | ||
3521 | c->aux = bb->aux; | |
3522 | while (c->aux) | |
3523 | c = (basic_block) c->aux; | |
3524 | ||
3525 | c->aux = bb; | |
3526 | bb->aux = NULL; | |
3527 | } | |
3528 | } | |
3529 | ||
3530 | /* In case there are more than one fallthru predecessors of exit, force that | |
3531 | there is only one. */ | |
3532 | ||
3533 | static void | |
3534 | force_one_exit_fallthru (void) | |
3535 | { | |
3536 | edge e, predecessor = NULL; | |
3537 | bool more = false; | |
3538 | edge_iterator ei; | |
3539 | basic_block forwarder, bb; | |
3540 | ||
3541 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) | |
3542 | if (e->flags & EDGE_FALLTHRU) | |
3543 | { | |
3544 | if (predecessor == NULL) | |
3545 | predecessor = e; | |
3546 | else | |
3547 | { | |
3548 | more = true; | |
3549 | break; | |
3550 | } | |
3551 | } | |
3552 | ||
3553 | if (!more) | |
3554 | return; | |
3555 | ||
3556 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
3557 | them. */ | |
3558 | forwarder = split_edge (predecessor); | |
3559 | for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); ) | |
3560 | { | |
3561 | if (e->src == forwarder | |
3562 | || !(e->flags & EDGE_FALLTHRU)) | |
3563 | ei_next (&ei); | |
3564 | else | |
3565 | redirect_edge_and_branch_force (e, forwarder); | |
3566 | } | |
3567 | ||
3568 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
3569 | exit block. */ | |
3570 | FOR_EACH_BB (bb) | |
3571 | { | |
3572 | if (bb->aux == NULL && bb != forwarder) | |
3573 | { | |
3574 | bb->aux = forwarder; | |
3575 | break; | |
3576 | } | |
3577 | } | |
3578 | } | |
3579 | \f | |
3580 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
3581 | ||
3582 | static bool | |
3583 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
3584 | { | |
3585 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
3586 | the dispatch table. This is difficult to do, as the instructions | |
3587 | computing jump destination may be hoisted outside the basic block. */ | |
3588 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
3589 | return false; | |
3590 | ||
3591 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
3592 | if (targetm.cannot_copy_insn_p) | |
3593 | { | |
3594 | rtx insn = BB_HEAD (bb); | |
3595 | while (1) | |
3596 | { | |
3597 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
3598 | return false; | |
3599 | if (insn == BB_END (bb)) | |
3600 | break; | |
3601 | insn = NEXT_INSN (insn); | |
3602 | } | |
3603 | } | |
3604 | ||
3605 | return true; | |
3606 | } | |
3607 | ||
3608 | rtx | |
3609 | duplicate_insn_chain (rtx from, rtx to) | |
3610 | { | |
39718607 | 3611 | rtx insn, next, last, copy; |
78bde837 SB |
3612 | |
3613 | /* Avoid updating of boundaries of previous basic block. The | |
3614 | note will get removed from insn stream in fixup. */ | |
3615 | last = emit_note (NOTE_INSN_DELETED); | |
3616 | ||
3617 | /* Create copy at the end of INSN chain. The chain will | |
3618 | be reordered later. */ | |
3619 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
3620 | { | |
3621 | switch (GET_CODE (insn)) | |
3622 | { | |
3623 | case DEBUG_INSN: | |
3624 | /* Don't duplicate label debug insns. */ | |
3625 | if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
3626 | break; | |
3627 | /* FALLTHRU */ | |
3628 | case INSN: | |
3629 | case CALL_INSN: | |
3630 | case JUMP_INSN: | |
78bde837 SB |
3631 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); |
3632 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
3633 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
3634 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
3635 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
3636 | break; | |
3637 | ||
39718607 SB |
3638 | case JUMP_TABLE_DATA: |
3639 | /* Avoid copying of dispatch tables. We never duplicate | |
3640 | tablejumps, so this can hit only in case the table got | |
3641 | moved far from original jump. | |
3642 | Avoid copying following barrier as well if any | |
3643 | (and debug insns in between). */ | |
3644 | for (next = NEXT_INSN (insn); | |
3645 | next != NEXT_INSN (to); | |
3646 | next = NEXT_INSN (next)) | |
3647 | if (!DEBUG_INSN_P (next)) | |
3648 | break; | |
3649 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
3650 | insn = next; | |
3651 | break; | |
3652 | ||
78bde837 SB |
3653 | case CODE_LABEL: |
3654 | break; | |
3655 | ||
3656 | case BARRIER: | |
3657 | emit_barrier (); | |
3658 | break; | |
3659 | ||
3660 | case NOTE: | |
3661 | switch (NOTE_KIND (insn)) | |
3662 | { | |
3663 | /* In case prologue is empty and function contain label | |
3664 | in first BB, we may want to copy the block. */ | |
3665 | case NOTE_INSN_PROLOGUE_END: | |
3666 | ||
3667 | case NOTE_INSN_DELETED: | |
3668 | case NOTE_INSN_DELETED_LABEL: | |
3669 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3670 | /* No problem to strip these. */ | |
3671 | case NOTE_INSN_FUNCTION_BEG: | |
3672 | /* There is always just single entry to function. */ | |
3673 | case NOTE_INSN_BASIC_BLOCK: | |
3674 | break; | |
3675 | ||
3676 | case NOTE_INSN_EPILOGUE_BEG: | |
3677 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
3678 | emit_note_copy (insn); | |
3679 | break; | |
3680 | ||
3681 | default: | |
3682 | /* All other notes should have already been eliminated. */ | |
3683 | gcc_unreachable (); | |
3684 | } | |
3685 | break; | |
3686 | default: | |
3687 | gcc_unreachable (); | |
3688 | } | |
3689 | } | |
3690 | insn = NEXT_INSN (last); | |
3691 | delete_insn (last); | |
3692 | return insn; | |
3693 | } | |
3694 | ||
3695 | /* Create a duplicate of the basic block BB. */ | |
3696 | ||
3697 | static basic_block | |
3698 | cfg_layout_duplicate_bb (basic_block bb) | |
3699 | { | |
3700 | rtx insn; | |
3701 | basic_block new_bb; | |
3702 | ||
3703 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb)); | |
3704 | new_bb = create_basic_block (insn, | |
3705 | insn ? get_last_insn () : NULL, | |
3706 | EXIT_BLOCK_PTR->prev_bb); | |
3707 | ||
3708 | BB_COPY_PARTITION (new_bb, bb); | |
3709 | if (BB_HEADER (bb)) | |
3710 | { | |
3711 | insn = BB_HEADER (bb); | |
3712 | while (NEXT_INSN (insn)) | |
3713 | insn = NEXT_INSN (insn); | |
3714 | insn = duplicate_insn_chain (BB_HEADER (bb), insn); | |
3715 | if (insn) | |
3716 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3717 | } | |
3718 | ||
3719 | if (BB_FOOTER (bb)) | |
3720 | { | |
3721 | insn = BB_FOOTER (bb); | |
3722 | while (NEXT_INSN (insn)) | |
3723 | insn = NEXT_INSN (insn); | |
3724 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn); | |
3725 | if (insn) | |
3726 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3727 | } | |
3728 | ||
3729 | return new_bb; | |
3730 | } | |
3731 | ||
3732 | \f | |
3733 | /* Main entry point to this module - initialize the datastructures for | |
3734 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
3735 | ||
3736 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
3737 | ||
3738 | void | |
3739 | cfg_layout_initialize (unsigned int flags) | |
3740 | { | |
3741 | rtx x; | |
3742 | basic_block bb; | |
3743 | ||
3744 | initialize_original_copy_tables (); | |
3745 | ||
3746 | cfg_layout_rtl_register_cfg_hooks (); | |
3747 | ||
3748 | record_effective_endpoints (); | |
3749 | ||
3750 | /* Make sure that the targets of non local gotos are marked. */ | |
3751 | for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1)) | |
3752 | { | |
3753 | bb = BLOCK_FOR_INSN (XEXP (x, 0)); | |
3754 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; | |
3755 | } | |
3756 | ||
3757 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
3758 | } | |
3759 | ||
3760 | /* Splits superblocks. */ | |
3761 | void | |
3762 | break_superblocks (void) | |
3763 | { | |
3764 | sbitmap superblocks; | |
3765 | bool need = false; | |
3766 | basic_block bb; | |
3767 | ||
3768 | superblocks = sbitmap_alloc (last_basic_block); | |
f61e445a | 3769 | bitmap_clear (superblocks); |
78bde837 SB |
3770 | |
3771 | FOR_EACH_BB (bb) | |
3772 | if (bb->flags & BB_SUPERBLOCK) | |
3773 | { | |
3774 | bb->flags &= ~BB_SUPERBLOCK; | |
d7c028c0 | 3775 | bitmap_set_bit (superblocks, bb->index); |
78bde837 SB |
3776 | need = true; |
3777 | } | |
3778 | ||
3779 | if (need) | |
3780 | { | |
3781 | rebuild_jump_labels (get_insns ()); | |
3782 | find_many_sub_basic_blocks (superblocks); | |
3783 | } | |
3784 | ||
3785 | free (superblocks); | |
3786 | } | |
3787 | ||
3788 | /* Finalize the changes: reorder insn list according to the sequence specified | |
3789 | by aux pointers, enter compensation code, rebuild scope forest. */ | |
3790 | ||
3791 | void | |
3792 | cfg_layout_finalize (void) | |
3793 | { | |
3794 | #ifdef ENABLE_CHECKING | |
3795 | verify_flow_info (); | |
3796 | #endif | |
3797 | force_one_exit_fallthru (); | |
3798 | rtl_register_cfg_hooks (); | |
3799 | if (reload_completed | |
3800 | #ifdef HAVE_epilogue | |
3801 | && !HAVE_epilogue | |
3802 | #endif | |
3803 | ) | |
3804 | fixup_fallthru_exit_predecessor (); | |
3805 | fixup_reorder_chain (); | |
3806 | ||
3807 | rebuild_jump_labels (get_insns ()); | |
3808 | delete_dead_jumptables (); | |
3809 | ||
3810 | #ifdef ENABLE_CHECKING | |
3811 | verify_insn_chain (); | |
3812 | verify_flow_info (); | |
3813 | #endif | |
3814 | } | |
3815 | ||
ba5e9aca | 3816 | |
9ee634e3 | 3817 | /* Same as split_block but update cfg_layout structures. */ |
f470c378 ZD |
3818 | |
3819 | static basic_block | |
d329e058 | 3820 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 | 3821 | { |
ae50c0cb | 3822 | rtx insn = (rtx) insnp; |
f470c378 | 3823 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 3824 | |
bcc708fc MM |
3825 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
3826 | BB_FOOTER (bb) = NULL; | |
9ee634e3 | 3827 | |
f470c378 | 3828 | return new_bb; |
9ee634e3 JH |
3829 | } |
3830 | ||
9ee634e3 | 3831 | /* Redirect Edge to DEST. */ |
6de9cd9a | 3832 | static edge |
d329e058 | 3833 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
3834 | { |
3835 | basic_block src = e->src; | |
6de9cd9a | 3836 | edge ret; |
9ee634e3 | 3837 | |
bc35512f | 3838 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 3839 | return NULL; |
bc35512f | 3840 | |
3348b696 | 3841 | if (e->dest == dest) |
6de9cd9a | 3842 | return e; |
bc35512f | 3843 | |
3348b696 | 3844 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a | 3845 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a | 3846 | { |
6fb5fa3c | 3847 | df_set_bb_dirty (src); |
6de9cd9a | 3848 | return ret; |
f345f21a | 3849 | } |
bc35512f JH |
3850 | |
3851 | if (e->src == ENTRY_BLOCK_PTR | |
3852 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) | |
3853 | { | |
c263766c RH |
3854 | if (dump_file) |
3855 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
3856 | e->src->index, dest->index); |
3857 | ||
6fb5fa3c | 3858 | df_set_bb_dirty (e->src); |
bc35512f | 3859 | redirect_edge_succ (e, dest); |
6de9cd9a | 3860 | return e; |
bc35512f JH |
3861 | } |
3862 | ||
9ee634e3 JH |
3863 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
3864 | in the case the basic block appears to be in sequence. Avoid this | |
3865 | transformation. */ | |
3866 | ||
9ee634e3 JH |
3867 | if (e->flags & EDGE_FALLTHRU) |
3868 | { | |
3869 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 3870 | if (JUMP_P (BB_END (src)) |
432f982f JH |
3871 | && label_is_jump_target_p (BB_HEAD (e->dest), |
3872 | BB_END (src))) | |
9ee634e3 | 3873 | { |
341c100f | 3874 | edge redirected; |
c22cacf3 | 3875 | |
c263766c RH |
3876 | if (dump_file) |
3877 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
3878 | "%i->%i redirected to %i\n", |
3879 | e->src->index, e->dest->index, dest->index); | |
3880 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
3881 | redirected = redirect_branch_edge (e, dest); |
3882 | gcc_assert (redirected); | |
0c617be4 JL |
3883 | redirected->flags |= EDGE_FALLTHRU; |
3884 | df_set_bb_dirty (redirected->src); | |
3885 | return redirected; | |
9ee634e3 JH |
3886 | } |
3887 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 3888 | of conditional jump, remove it. */ |
628f6a4e | 3889 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 3890 | { |
03101c6f KH |
3891 | /* Find the edge that is different from E. */ |
3892 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 3893 | |
9ee634e3 | 3894 | if (s->dest == dest |
a813c111 SB |
3895 | && any_condjump_p (BB_END (src)) |
3896 | && onlyjump_p (BB_END (src))) | |
3897 | delete_insn (BB_END (src)); | |
9ee634e3 | 3898 | } |
c263766c | 3899 | if (dump_file) |
dc764d10 | 3900 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
bc35512f | 3901 | e->src->index, e->dest->index, dest->index); |
0c617be4 | 3902 | ret = redirect_edge_succ_nodup (e, dest); |
9ee634e3 JH |
3903 | } |
3904 | else | |
bc35512f | 3905 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
3906 | |
3907 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
341c100f | 3908 | gcc_assert (!simplejump_p (BB_END (src))); |
9ee634e3 | 3909 | |
6fb5fa3c | 3910 | df_set_bb_dirty (src); |
9ee634e3 JH |
3911 | return ret; |
3912 | } | |
3913 | ||
3914 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
3915 | static basic_block | |
d329e058 | 3916 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 3917 | { |
341c100f NS |
3918 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
3919 | ||
3920 | gcc_assert (redirected); | |
9ee634e3 JH |
3921 | return NULL; |
3922 | } | |
3923 | ||
f470c378 ZD |
3924 | /* Same as delete_basic_block but update cfg_layout structures. */ |
3925 | ||
9ee634e3 | 3926 | static void |
d329e058 | 3927 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 3928 | { |
a813c111 | 3929 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 3930 | |
bcc708fc | 3931 | if (BB_HEADER (bb)) |
9ee634e3 | 3932 | { |
a813c111 | 3933 | next = BB_HEAD (bb); |
9ee634e3 | 3934 | if (prev) |
bcc708fc | 3935 | NEXT_INSN (prev) = BB_HEADER (bb); |
9ee634e3 | 3936 | else |
bcc708fc MM |
3937 | set_first_insn (BB_HEADER (bb)); |
3938 | PREV_INSN (BB_HEADER (bb)) = prev; | |
3939 | insn = BB_HEADER (bb); | |
9ee634e3 JH |
3940 | while (NEXT_INSN (insn)) |
3941 | insn = NEXT_INSN (insn); | |
3942 | NEXT_INSN (insn) = next; | |
3943 | PREV_INSN (next) = insn; | |
3944 | } | |
a813c111 | 3945 | next = NEXT_INSN (BB_END (bb)); |
bcc708fc | 3946 | if (BB_FOOTER (bb)) |
9ee634e3 | 3947 | { |
bcc708fc | 3948 | insn = BB_FOOTER (bb); |
bc35512f JH |
3949 | while (insn) |
3950 | { | |
4b4bf941 | 3951 | if (BARRIER_P (insn)) |
bc35512f JH |
3952 | { |
3953 | if (PREV_INSN (insn)) | |
3954 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
3955 | else | |
bcc708fc | 3956 | BB_FOOTER (bb) = NEXT_INSN (insn); |
bc35512f JH |
3957 | if (NEXT_INSN (insn)) |
3958 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
3959 | } | |
4b4bf941 | 3960 | if (LABEL_P (insn)) |
bc35512f JH |
3961 | break; |
3962 | insn = NEXT_INSN (insn); | |
3963 | } | |
bcc708fc | 3964 | if (BB_FOOTER (bb)) |
bc35512f | 3965 | { |
a813c111 | 3966 | insn = BB_END (bb); |
bcc708fc MM |
3967 | NEXT_INSN (insn) = BB_FOOTER (bb); |
3968 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
bc35512f JH |
3969 | while (NEXT_INSN (insn)) |
3970 | insn = NEXT_INSN (insn); | |
3971 | NEXT_INSN (insn) = next; | |
3972 | if (next) | |
3973 | PREV_INSN (next) = insn; | |
3974 | else | |
3975 | set_last_insn (insn); | |
3976 | } | |
9ee634e3 JH |
3977 | } |
3978 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
bcc708fc | 3979 | to = &BB_HEADER (bb->next_bb); |
9ee634e3 JH |
3980 | else |
3981 | to = &cfg_layout_function_footer; | |
997de8ed | 3982 | |
9ee634e3 JH |
3983 | rtl_delete_block (bb); |
3984 | ||
3985 | if (prev) | |
3986 | prev = NEXT_INSN (prev); | |
d329e058 | 3987 | else |
9ee634e3 JH |
3988 | prev = get_insns (); |
3989 | if (next) | |
3990 | next = PREV_INSN (next); | |
d329e058 | 3991 | else |
9ee634e3 JH |
3992 | next = get_last_insn (); |
3993 | ||
3994 | if (next && NEXT_INSN (next) != prev) | |
3995 | { | |
3996 | remaints = unlink_insn_chain (prev, next); | |
3997 | insn = remaints; | |
3998 | while (NEXT_INSN (insn)) | |
3999 | insn = NEXT_INSN (insn); | |
4000 | NEXT_INSN (insn) = *to; | |
4001 | if (*to) | |
4002 | PREV_INSN (*to) = insn; | |
4003 | *to = remaints; | |
4004 | } | |
4005 | } | |
4006 | ||
beb235f8 | 4007 | /* Return true when blocks A and B can be safely merged. */ |
b48d0358 | 4008 | |
bc35512f | 4009 | static bool |
b48d0358 | 4010 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
bc35512f | 4011 | { |
750054a2 CT |
4012 | /* If we are partitioning hot/cold basic blocks, we don't want to |
4013 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
4014 | and cold sections. |
4015 | ||
8e8d5162 | 4016 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
4017 | be optimizable (or blocks that appear to be mergeable), but which really |
4018 | must be left untouched (they are required to make it safely across | |
4019 | partition boundaries). See the comments at the top of | |
8e8d5162 CT |
4020 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
4021 | ||
87c8b4be | 4022 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 4023 | return false; |
750054a2 | 4024 | |
7d776ee2 RG |
4025 | /* Protect the loop latches. */ |
4026 | if (current_loops && b->loop_father->latch == b) | |
4027 | return false; | |
4028 | ||
894a84b5 BS |
4029 | /* If we would end up moving B's instructions, make sure it doesn't fall |
4030 | through into the exit block, since we cannot recover from a fallthrough | |
4031 | edge into the exit block occurring in the middle of a function. */ | |
4032 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
4033 | { | |
4034 | edge e = find_fallthru_edge (b->succs); | |
4035 | if (e && e->dest == EXIT_BLOCK_PTR) | |
4036 | return false; | |
4037 | } | |
4038 | ||
bc35512f | 4039 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
4040 | return (single_succ_p (a) |
4041 | && single_succ (a) == b | |
4042 | && single_pred_p (b) == 1 | |
628f6a4e | 4043 | && a != b |
bc35512f | 4044 | /* Must be simple edge. */ |
c5cbcccf | 4045 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f | 4046 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR |
49ea3702 SB |
4047 | /* If the jump insn has side effects, we can't kill the edge. |
4048 | When not optimizing, try_redirect_by_replacing_jump will | |
4049 | not allow us to redirect an edge by replacing a table jump. */ | |
4b4bf941 | 4050 | && (!JUMP_P (BB_END (a)) |
49ea3702 | 4051 | || ((!optimize || reload_completed) |
a813c111 | 4052 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
4053 | } |
4054 | ||
41806d92 NS |
4055 | /* Merge block A and B. The blocks must be mergeable. */ |
4056 | ||
bc35512f JH |
4057 | static void |
4058 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4059 | { | |
50a36e42 | 4060 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
f9df6f16 | 4061 | rtx insn; |
50a36e42 | 4062 | |
77a74ed7 | 4063 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f | 4064 | |
6fb5fa3c | 4065 | if (dump_file) |
50a36e42 EB |
4066 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4067 | a->index); | |
6fb5fa3c | 4068 | |
bc35512f | 4069 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 4070 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 | 4071 | { |
2c97f8e4 RH |
4072 | delete_insn (BB_HEAD (b)); |
4073 | } | |
bc35512f JH |
4074 | |
4075 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4076 | it cleaned up. */ | |
4b4bf941 | 4077 | if (JUMP_P (BB_END (a))) |
628f6a4e | 4078 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 4079 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f | 4080 | |
9be94227 | 4081 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
7241571e | 4082 | some unique locus, emit a nop with that locus in between. */ |
9be94227 EB |
4083 | if (!optimize) |
4084 | emit_nop_for_unique_locus_between (a, b); | |
7241571e | 4085 | |
4c8af858 SB |
4086 | /* Move things from b->footer after a->footer. */ |
4087 | if (BB_FOOTER (b)) | |
bc35512f | 4088 | { |
4c8af858 SB |
4089 | if (!BB_FOOTER (a)) |
4090 | BB_FOOTER (a) = BB_FOOTER (b); | |
4091 | else | |
4092 | { | |
4093 | rtx last = BB_FOOTER (a); | |
4094 | ||
4095 | while (NEXT_INSN (last)) | |
4096 | last = NEXT_INSN (last); | |
4097 | NEXT_INSN (last) = BB_FOOTER (b); | |
4098 | PREV_INSN (BB_FOOTER (b)) = last; | |
4099 | } | |
4100 | BB_FOOTER (b) = NULL; | |
4101 | } | |
4102 | ||
4103 | /* Move things from b->header before a->footer. | |
4104 | Note that this may include dead tablejump data, but we don't clean | |
4105 | those up until we go out of cfglayout mode. */ | |
4106 | if (BB_HEADER (b)) | |
4107 | { | |
4108 | if (! BB_FOOTER (a)) | |
4109 | BB_FOOTER (a) = BB_HEADER (b); | |
4110 | else | |
4111 | { | |
4112 | rtx last = BB_HEADER (b); | |
4113 | ||
4114 | while (NEXT_INSN (last)) | |
4115 | last = NEXT_INSN (last); | |
4116 | NEXT_INSN (last) = BB_FOOTER (a); | |
4117 | PREV_INSN (BB_FOOTER (a)) = last; | |
4118 | BB_FOOTER (a) = BB_HEADER (b); | |
4119 | } | |
bcc708fc | 4120 | BB_HEADER (b) = NULL; |
bc35512f JH |
4121 | } |
4122 | ||
4123 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 4124 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 4125 | { |
f9df6f16 | 4126 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
6c3d0e31 | 4127 | |
f9df6f16 | 4128 | emit_insn_after_noloc (insn, BB_END (a), a); |
bc35512f JH |
4129 | } |
4130 | /* Otherwise just re-associate the instructions. */ | |
4131 | else | |
4132 | { | |
a813c111 | 4133 | insn = BB_HEAD (b); |
a813c111 | 4134 | BB_END (a) = BB_END (b); |
bc35512f JH |
4135 | } |
4136 | ||
f9df6f16 JJ |
4137 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4138 | We need to explicitly call. */ | |
4139 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4140 | ||
4141 | /* Skip possible DELETED_LABEL insn. */ | |
4142 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4143 | insn = NEXT_INSN (insn); | |
4144 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
4c8af858 | 4145 | BB_HEAD (b) = BB_END (b) = NULL; |
f9df6f16 JJ |
4146 | delete_insn (insn); |
4147 | ||
6fb5fa3c DB |
4148 | df_bb_delete (b->index); |
4149 | ||
50a36e42 | 4150 | /* If B was a forwarder block, propagate the locus on the edge. */ |
2f13f2de | 4151 | if (forwarder_p |
fbc68f2a | 4152 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) |
50a36e42 EB |
4153 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4154 | ||
c263766c | 4155 | if (dump_file) |
50a36e42 | 4156 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
bc35512f JH |
4157 | } |
4158 | ||
4159 | /* Split edge E. */ | |
f470c378 | 4160 | |
bc35512f JH |
4161 | static basic_block |
4162 | cfg_layout_split_edge (edge e) | |
4163 | { | |
bc35512f JH |
4164 | basic_block new_bb = |
4165 | create_basic_block (e->src != ENTRY_BLOCK_PTR | |
a813c111 | 4166 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
4167 | NULL_RTX, e->src); |
4168 | ||
3e7eb734 JJ |
4169 | if (e->dest == EXIT_BLOCK_PTR) |
4170 | BB_COPY_PARTITION (new_bb, e->src); | |
4171 | else | |
4172 | BB_COPY_PARTITION (new_bb, e->dest); | |
a9b2ee88 | 4173 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
4174 | redirect_edge_and_branch_force (e, new_bb); |
4175 | ||
4176 | return new_bb; | |
4177 | } | |
4178 | ||
f470c378 ZD |
4179 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
4180 | ||
4181 | static void | |
4182 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
4183 | { | |
4184 | } | |
4185 | ||
df92c640 SB |
4186 | /* Return true if BB contains only labels or non-executable |
4187 | instructions. */ | |
4188 | ||
4189 | static bool | |
4190 | rtl_block_empty_p (basic_block bb) | |
4191 | { | |
4192 | rtx insn; | |
4193 | ||
4194 | if (bb == ENTRY_BLOCK_PTR || bb == EXIT_BLOCK_PTR) | |
4195 | return true; | |
4196 | ||
4197 | FOR_BB_INSNS (bb, insn) | |
4198 | if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn)) | |
4199 | return false; | |
4200 | ||
4201 | return true; | |
4202 | } | |
4203 | ||
4204 | /* Split a basic block if it ends with a conditional branch and if | |
4205 | the other part of the block is not empty. */ | |
4206 | ||
4207 | static basic_block | |
4208 | rtl_split_block_before_cond_jump (basic_block bb) | |
4209 | { | |
4210 | rtx insn; | |
4211 | rtx split_point = NULL; | |
4212 | rtx last = NULL; | |
4213 | bool found_code = false; | |
4214 | ||
4215 | FOR_BB_INSNS (bb, insn) | |
4216 | { | |
4217 | if (any_condjump_p (insn)) | |
4218 | split_point = last; | |
4219 | else if (NONDEBUG_INSN_P (insn)) | |
4220 | found_code = true; | |
4221 | last = insn; | |
4222 | } | |
4223 | ||
4224 | /* Did not find everything. */ | |
4225 | if (found_code && split_point) | |
4226 | return split_block (bb, split_point)->dest; | |
4227 | else | |
4228 | return NULL; | |
4229 | } | |
4230 | ||
6de9cd9a DN |
4231 | /* Return 1 if BB ends with a call, possibly followed by some |
4232 | instructions that must stay with the call, 0 otherwise. */ | |
4233 | ||
4234 | static bool | |
b48d0358 | 4235 | rtl_block_ends_with_call_p (basic_block bb) |
6de9cd9a DN |
4236 | { |
4237 | rtx insn = BB_END (bb); | |
4238 | ||
4b4bf941 | 4239 | while (!CALL_P (insn) |
6de9cd9a | 4240 | && insn != BB_HEAD (bb) |
92ddef69 | 4241 | && (keep_with_call_p (insn) |
b5b8b0ac AO |
4242 | || NOTE_P (insn) |
4243 | || DEBUG_INSN_P (insn))) | |
6de9cd9a | 4244 | insn = PREV_INSN (insn); |
4b4bf941 | 4245 | return (CALL_P (insn)); |
6de9cd9a DN |
4246 | } |
4247 | ||
4248 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
4249 | ||
4250 | static bool | |
9678086d | 4251 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
6de9cd9a DN |
4252 | { |
4253 | return any_condjump_p (BB_END (bb)); | |
4254 | } | |
4255 | ||
4256 | /* Return true if we need to add fake edge to exit. | |
4257 | Helper function for rtl_flow_call_edges_add. */ | |
4258 | ||
4259 | static bool | |
9678086d | 4260 | need_fake_edge_p (const_rtx insn) |
6de9cd9a DN |
4261 | { |
4262 | if (!INSN_P (insn)) | |
4263 | return false; | |
4264 | ||
4b4bf941 | 4265 | if ((CALL_P (insn) |
6de9cd9a DN |
4266 | && !SIBLING_CALL_P (insn) |
4267 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
becfd6e5 | 4268 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
6de9cd9a DN |
4269 | return true; |
4270 | ||
4271 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
4272 | && MEM_VOLATILE_P (PATTERN (insn))) | |
4273 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
4274 | && asm_noperands (insn) != -1 | |
4275 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
4276 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
4277 | } | |
4278 | ||
4279 | /* Add fake edges to the function exit for any non constant and non noreturn | |
4280 | calls, volatile inline assembly in the bitmap of blocks specified by | |
4281 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
4282 | that were split. | |
4283 | ||
4284 | The goal is to expose cases in which entering a basic block does not imply | |
4285 | that all subsequent instructions must be executed. */ | |
4286 | ||
4287 | static int | |
4288 | rtl_flow_call_edges_add (sbitmap blocks) | |
4289 | { | |
4290 | int i; | |
4291 | int blocks_split = 0; | |
4292 | int last_bb = last_basic_block; | |
4293 | bool check_last_block = false; | |
4294 | ||
24bd1a0b | 4295 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
4296 | return 0; |
4297 | ||
4298 | if (! blocks) | |
4299 | check_last_block = true; | |
4300 | else | |
d7c028c0 | 4301 | check_last_block = bitmap_bit_p (blocks, EXIT_BLOCK_PTR->prev_bb->index); |
6de9cd9a DN |
4302 | |
4303 | /* In the last basic block, before epilogue generation, there will be | |
4304 | a fallthru edge to EXIT. Special care is required if the last insn | |
4305 | of the last basic block is a call because make_edge folds duplicate | |
4306 | edges, which would result in the fallthru edge also being marked | |
4307 | fake, which would result in the fallthru edge being removed by | |
4308 | remove_fake_edges, which would result in an invalid CFG. | |
4309 | ||
4310 | Moreover, we can't elide the outgoing fake edge, since the block | |
4311 | profiler needs to take this into account in order to solve the minimal | |
4312 | spanning tree in the case that the call doesn't return. | |
4313 | ||
4314 | Handle this by adding a dummy instruction in a new last basic block. */ | |
4315 | if (check_last_block) | |
4316 | { | |
4317 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
4318 | rtx insn = BB_END (bb); | |
4319 | ||
4320 | /* Back up past insns that must be kept in the same block as a call. */ | |
4321 | while (insn != BB_HEAD (bb) | |
4322 | && keep_with_call_p (insn)) | |
4323 | insn = PREV_INSN (insn); | |
4324 | ||
4325 | if (need_fake_edge_p (insn)) | |
4326 | { | |
4327 | edge e; | |
4328 | ||
9ff3d2de JL |
4329 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4330 | if (e) | |
4331 | { | |
c41c1387 | 4332 | insert_insn_on_edge (gen_use (const0_rtx), e); |
9ff3d2de JL |
4333 | commit_edge_insertions (); |
4334 | } | |
6de9cd9a DN |
4335 | } |
4336 | } | |
4337 | ||
4338 | /* Now add fake edges to the function exit for any non constant | |
4339 | calls since there is no way that we can determine if they will | |
4340 | return or not... */ | |
4341 | ||
24bd1a0b | 4342 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a DN |
4343 | { |
4344 | basic_block bb = BASIC_BLOCK (i); | |
4345 | rtx insn; | |
4346 | rtx prev_insn; | |
4347 | ||
4348 | if (!bb) | |
4349 | continue; | |
4350 | ||
d7c028c0 | 4351 | if (blocks && !bitmap_bit_p (blocks, i)) |
6de9cd9a DN |
4352 | continue; |
4353 | ||
4354 | for (insn = BB_END (bb); ; insn = prev_insn) | |
4355 | { | |
4356 | prev_insn = PREV_INSN (insn); | |
4357 | if (need_fake_edge_p (insn)) | |
4358 | { | |
4359 | edge e; | |
4360 | rtx split_at_insn = insn; | |
4361 | ||
4362 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 4363 | remain in the same block as the call. */ |
4b4bf941 | 4364 | if (CALL_P (insn)) |
6de9cd9a DN |
4365 | while (split_at_insn != BB_END (bb) |
4366 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
4367 | split_at_insn = NEXT_INSN (split_at_insn); | |
4368 | ||
4369 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 4370 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
4371 | block in CFG already. Calling make_edge in such case would |
4372 | cause us to mark that edge as fake and remove it later. */ | |
4373 | ||
4374 | #ifdef ENABLE_CHECKING | |
4375 | if (split_at_insn == BB_END (bb)) | |
628f6a4e | 4376 | { |
9ff3d2de JL |
4377 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4378 | gcc_assert (e == NULL); | |
628f6a4e | 4379 | } |
6de9cd9a DN |
4380 | #endif |
4381 | ||
4382 | /* Note that the following may create a new basic block | |
4383 | and renumber the existing basic blocks. */ | |
4384 | if (split_at_insn != BB_END (bb)) | |
4385 | { | |
4386 | e = split_block (bb, split_at_insn); | |
4387 | if (e) | |
4388 | blocks_split++; | |
4389 | } | |
4390 | ||
4391 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
4392 | } | |
4393 | ||
4394 | if (insn == BB_HEAD (bb)) | |
4395 | break; | |
4396 | } | |
4397 | } | |
4398 | ||
4399 | if (blocks_split) | |
4400 | verify_flow_info (); | |
4401 | ||
4402 | return blocks_split; | |
4403 | } | |
4404 | ||
1cb7dfc3 | 4405 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 4406 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
4407 | there is no need to handle this here the loop versioning code handles |
4408 | this. the reason for SECON_HEAD is that it is needed for condition | |
4409 | in trees, and this should be of the same type since it is a hook. */ | |
4410 | static void | |
4411 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
4412 | basic_block second_head ATTRIBUTE_UNUSED, |
4413 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 MH |
4414 | { |
4415 | rtx label, seq, jump; | |
4416 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
4417 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
4418 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
4419 | enum machine_mode mode; | |
4420 | ||
4421 | ||
4422 | label = block_label (first_head); | |
4423 | mode = GET_MODE (op0); | |
4424 | if (mode == VOIDmode) | |
4425 | mode = GET_MODE (op1); | |
4426 | ||
4427 | start_sequence (); | |
4428 | op0 = force_operand (op0, NULL_RTX); | |
4429 | op1 = force_operand (op1, NULL_RTX); | |
4430 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
40e90eac | 4431 | mode, NULL_RTX, NULL_RTX, label, -1); |
1cb7dfc3 MH |
4432 | jump = get_last_insn (); |
4433 | JUMP_LABEL (jump) = label; | |
4434 | LABEL_NUSES (label)++; | |
4435 | seq = get_insns (); | |
4436 | end_sequence (); | |
4437 | ||
4438 | /* Add the new cond , in the new head. */ | |
4439 | emit_insn_after(seq, BB_END(cond_bb)); | |
4440 | } | |
4441 | ||
4442 | ||
4443 | /* Given a block B with unconditional branch at its end, get the | |
4444 | store the return the branch edge and the fall-thru edge in | |
4445 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
4446 | static void | |
4447 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
4448 | edge *fallthru_edge) | |
4449 | { | |
4450 | edge e = EDGE_SUCC (b, 0); | |
4451 | ||
4452 | if (e->flags & EDGE_FALLTHRU) | |
4453 | { | |
4454 | *fallthru_edge = e; | |
4455 | *branch_edge = EDGE_SUCC (b, 1); | |
4456 | } | |
4457 | else | |
4458 | { | |
4459 | *branch_edge = e; | |
4460 | *fallthru_edge = EDGE_SUCC (b, 1); | |
4461 | } | |
4462 | } | |
4463 | ||
5e2d947c JH |
4464 | void |
4465 | init_rtl_bb_info (basic_block bb) | |
4466 | { | |
bcc708fc MM |
4467 | gcc_assert (!bb->il.x.rtl); |
4468 | bb->il.x.head_ = NULL; | |
4469 | bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info (); | |
5e2d947c JH |
4470 | } |
4471 | ||
14fa2cc0 ZD |
4472 | /* Returns true if it is possible to remove edge E by redirecting |
4473 | it to the destination of the other edge from E->src. */ | |
4474 | ||
4475 | static bool | |
9678086d | 4476 | rtl_can_remove_branch_p (const_edge e) |
14fa2cc0 | 4477 | { |
9678086d KG |
4478 | const_basic_block src = e->src; |
4479 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
4480 | const_rtx insn = BB_END (src), set; | |
14fa2cc0 ZD |
4481 | |
4482 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
4483 | if (target == EXIT_BLOCK_PTR) | |
4484 | return false; | |
4485 | ||
4486 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
4487 | return false; | |
4488 | ||
4489 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) | |
4490 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
4491 | return false; | |
4492 | ||
4493 | if (!onlyjump_p (insn) | |
4494 | || tablejump_p (insn, NULL, NULL)) | |
4495 | return false; | |
4496 | ||
4497 | set = single_set (insn); | |
4498 | if (!set || side_effects_p (set)) | |
4499 | return false; | |
4500 | ||
4501 | return true; | |
4502 | } | |
4503 | ||
ffe14686 AM |
4504 | static basic_block |
4505 | rtl_duplicate_bb (basic_block bb) | |
4506 | { | |
4507 | bb = cfg_layout_duplicate_bb (bb); | |
4508 | bb->aux = NULL; | |
4509 | return bb; | |
4510 | } | |
4511 | ||
aa4723d7 SB |
4512 | /* Do book-keeping of basic block BB for the profile consistency checker. |
4513 | If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1 | |
4514 | then do post-pass accounting. Store the counting in RECORD. */ | |
4515 | static void | |
4516 | rtl_account_profile_record (basic_block bb, int after_pass, | |
4517 | struct profile_record *record) | |
4518 | { | |
4519 | rtx insn; | |
4520 | FOR_BB_INSNS (bb, insn) | |
4521 | if (INSN_P (insn)) | |
4522 | { | |
4523 | record->size[after_pass] | |
4524 | += insn_rtx_cost (PATTERN (insn), false); | |
4525 | if (profile_status == PROFILE_READ) | |
4526 | record->time[after_pass] | |
4527 | += insn_rtx_cost (PATTERN (insn), true) * bb->count; | |
4528 | else if (profile_status == PROFILE_GUESSED) | |
4529 | record->time[after_pass] | |
4530 | += insn_rtx_cost (PATTERN (insn), true) * bb->frequency; | |
4531 | } | |
4532 | } | |
4533 | ||
9ee634e3 JH |
4534 | /* Implementation of CFG manipulation for linearized RTL. */ |
4535 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 4536 | "rtl", |
9ee634e3 | 4537 | rtl_verify_flow_info, |
10e9fecc | 4538 | rtl_dump_bb, |
2c895bd1 | 4539 | rtl_dump_bb_for_graph, |
bc35512f | 4540 | rtl_create_basic_block, |
9ee634e3 JH |
4541 | rtl_redirect_edge_and_branch, |
4542 | rtl_redirect_edge_and_branch_force, | |
14fa2cc0 | 4543 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4544 | rtl_delete_block, |
4545 | rtl_split_block, | |
f470c378 | 4546 | rtl_move_block_after, |
bc35512f JH |
4547 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
4548 | rtl_merge_blocks, | |
6de9cd9a DN |
4549 | rtl_predict_edge, |
4550 | rtl_predicted_by_p, | |
ffe14686 AM |
4551 | cfg_layout_can_duplicate_bb_p, |
4552 | rtl_duplicate_bb, | |
f470c378 ZD |
4553 | rtl_split_edge, |
4554 | rtl_make_forwarder_block, | |
6de9cd9a | 4555 | rtl_tidy_fallthru_edge, |
cf103ca4 | 4556 | rtl_force_nonfallthru, |
6de9cd9a DN |
4557 | rtl_block_ends_with_call_p, |
4558 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4559 | rtl_flow_call_edges_add, |
4560 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4561 | NULL, /* execute_on_shrinking_pred */ |
4562 | NULL, /* duplicate loop for trees */ | |
4563 | NULL, /* lv_add_condition_to_bb */ | |
4564 | NULL, /* lv_adjust_loop_header_phi*/ | |
4565 | NULL, /* extract_cond_bb_edges */ | |
df92c640 SB |
4566 | NULL, /* flush_pending_stmts */ |
4567 | rtl_block_empty_p, /* block_empty_p */ | |
4568 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4569 | rtl_account_profile_record, |
9ee634e3 JH |
4570 | }; |
4571 | ||
4572 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
4573 | basic block connected via fallthru edges does not have to be adjacent. | |
4574 | This representation will hopefully become the default one in future | |
4575 | version of the compiler. */ | |
6de9cd9a | 4576 | |
9ee634e3 | 4577 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 4578 | "cfglayout mode", |
bc35512f | 4579 | rtl_verify_flow_info_1, |
10e9fecc | 4580 | rtl_dump_bb, |
2c895bd1 | 4581 | rtl_dump_bb_for_graph, |
bc35512f | 4582 | cfg_layout_create_basic_block, |
9ee634e3 JH |
4583 | cfg_layout_redirect_edge_and_branch, |
4584 | cfg_layout_redirect_edge_and_branch_force, | |
14fa2cc0 | 4585 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4586 | cfg_layout_delete_block, |
4587 | cfg_layout_split_block, | |
f470c378 | 4588 | rtl_move_block_after, |
bc35512f JH |
4589 | cfg_layout_can_merge_blocks_p, |
4590 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
4591 | rtl_predict_edge, |
4592 | rtl_predicted_by_p, | |
4593 | cfg_layout_can_duplicate_bb_p, | |
4594 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
4595 | cfg_layout_split_edge, |
4596 | rtl_make_forwarder_block, | |
cf103ca4 EB |
4597 | NULL, /* tidy_fallthru_edge */ |
4598 | rtl_force_nonfallthru, | |
6de9cd9a DN |
4599 | rtl_block_ends_with_call_p, |
4600 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4601 | rtl_flow_call_edges_add, |
4602 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4603 | NULL, /* execute_on_shrinking_pred */ |
4604 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
4605 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
4606 | NULL, /* lv_adjust_loop_header_phi*/ | |
4607 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
df92c640 SB |
4608 | NULL, /* flush_pending_stmts */ |
4609 | rtl_block_empty_p, /* block_empty_p */ | |
4610 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4611 | rtl_account_profile_record, |
9ee634e3 | 4612 | }; |
78bde837 SB |
4613 | |
4614 | #include "gt-cfgrtl.h" |