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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)); |
ca6c03ca JH |
167 | remove_insn (insn); |
168 | INSN_DELETED_P (insn) = 1; | |
169 | } | |
170 | ||
171 | /* If deleting a jump, decrement the use count of the label. Deleting | |
172 | the label itself should happen in the normal course of block merging. */ | |
cf7c4aa6 | 173 | if (JUMP_P (insn)) |
9295a326 | 174 | { |
cf7c4aa6 HPN |
175 | if (JUMP_LABEL (insn) |
176 | && LABEL_P (JUMP_LABEL (insn))) | |
177 | LABEL_NUSES (JUMP_LABEL (insn))--; | |
178 | ||
179 | /* If there are more targets, remove them too. */ | |
180 | while ((note | |
181 | = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX | |
4b4bf941 | 182 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
183 | { |
184 | LABEL_NUSES (XEXP (note, 0))--; | |
185 | remove_note (insn, note); | |
186 | } | |
187 | } | |
ca6c03ca | 188 | |
cf7c4aa6 HPN |
189 | /* Also if deleting any insn that references a label as an operand. */ |
190 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX | |
191 | && LABEL_P (XEXP (note, 0))) | |
192 | { | |
193 | LABEL_NUSES (XEXP (note, 0))--; | |
194 | remove_note (insn, note); | |
195 | } | |
196 | ||
481683e1 | 197 | if (JUMP_TABLE_DATA_P (insn)) |
ca6c03ca JH |
198 | { |
199 | rtx pat = PATTERN (insn); | |
200 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
201 | int len = XVECLEN (pat, diff_vec_p); | |
202 | int i; | |
203 | ||
204 | for (i = 0; i < len; i++) | |
a124fcda RH |
205 | { |
206 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
207 | ||
208 | /* When deleting code in bulk (e.g. removing many unreachable | |
209 | blocks) we can delete a label that's a target of the vector | |
210 | before deleting the vector itself. */ | |
4b4bf941 | 211 | if (!NOTE_P (label)) |
a124fcda RH |
212 | LABEL_NUSES (label)--; |
213 | } | |
ca6c03ca | 214 | } |
ca6c03ca JH |
215 | } |
216 | ||
3dec4024 | 217 | /* Like delete_insn but also purge dead edges from BB. */ |
9ed7b221 | 218 | |
03fbe718 | 219 | void |
d329e058 | 220 | delete_insn_and_edges (rtx insn) |
3dec4024 | 221 | { |
3dec4024 JH |
222 | bool purge = false; |
223 | ||
ba4f7968 | 224 | if (INSN_P (insn) |
3dec4024 | 225 | && BLOCK_FOR_INSN (insn) |
a813c111 | 226 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 | 227 | purge = true; |
03fbe718 | 228 | delete_insn (insn); |
3dec4024 JH |
229 | if (purge) |
230 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
3dec4024 JH |
231 | } |
232 | ||
ca6c03ca | 233 | /* Unlink a chain of insns between START and FINISH, leaving notes |
a7b87f73 ZD |
234 | that must be paired. If CLEAR_BB is true, we set bb field for |
235 | insns that cannot be removed to NULL. */ | |
ca6c03ca JH |
236 | |
237 | void | |
a7b87f73 | 238 | delete_insn_chain (rtx start, rtx finish, bool clear_bb) |
ca6c03ca | 239 | { |
03fbe718 | 240 | rtx prev, current; |
ca6c03ca | 241 | |
5f0d2358 RK |
242 | /* Unchain the insns one by one. It would be quicker to delete all of these |
243 | with a single unchaining, rather than one at a time, but we need to keep | |
244 | the NOTE's. */ | |
03fbe718 | 245 | current = finish; |
ca6c03ca JH |
246 | while (1) |
247 | { | |
03fbe718 TV |
248 | prev = PREV_INSN (current); |
249 | if (NOTE_P (current) && !can_delete_note_p (current)) | |
ca6c03ca JH |
250 | ; |
251 | else | |
03fbe718 | 252 | delete_insn (current); |
ca6c03ca | 253 | |
03fbe718 TV |
254 | if (clear_bb && !INSN_DELETED_P (current)) |
255 | set_block_for_insn (current, NULL); | |
a7b87f73 | 256 | |
03fbe718 | 257 | if (current == start) |
ca6c03ca | 258 | break; |
03fbe718 | 259 | current = prev; |
ca6c03ca JH |
260 | } |
261 | } | |
262 | \f | |
5f0d2358 RK |
263 | /* Create a new basic block consisting of the instructions between HEAD and END |
264 | inclusive. This function is designed to allow fast BB construction - reuses | |
265 | the note and basic block struct in BB_NOTE, if any and do not grow | |
266 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
267 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
268 | and HEAD can be NULL to create basic block at the end of INSN chain. |
269 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
270 | |
271 | basic_block | |
d329e058 | 272 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
273 | { |
274 | basic_block bb; | |
275 | ||
276 | if (bb_note | |
ca6c03ca JH |
277 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
278 | && bb->aux == NULL) | |
279 | { | |
280 | /* If we found an existing note, thread it back onto the chain. */ | |
281 | ||
282 | rtx after; | |
283 | ||
4b4bf941 | 284 | if (LABEL_P (head)) |
ca6c03ca JH |
285 | after = head; |
286 | else | |
287 | { | |
288 | after = PREV_INSN (head); | |
289 | head = bb_note; | |
290 | } | |
291 | ||
292 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 293 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
294 | } |
295 | else | |
296 | { | |
297 | /* Otherwise we must create a note and a basic block structure. */ | |
298 | ||
299 | bb = alloc_block (); | |
300 | ||
5e2d947c | 301 | init_rtl_bb_info (bb); |
ca6c03ca | 302 | if (!head && !end) |
5f0d2358 RK |
303 | head = end = bb_note |
304 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 305 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
306 | { |
307 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
308 | if (head == end) | |
309 | end = bb_note; | |
310 | } | |
311 | else | |
312 | { | |
313 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
314 | head = bb_note; | |
315 | if (!end) | |
316 | end = head; | |
317 | } | |
5f0d2358 | 318 | |
ca6c03ca JH |
319 | NOTE_BASIC_BLOCK (bb_note) = bb; |
320 | } | |
321 | ||
322 | /* Always include the bb note in the block. */ | |
323 | if (NEXT_INSN (end) == bb_note) | |
324 | end = bb_note; | |
325 | ||
a813c111 SB |
326 | BB_HEAD (bb) = head; |
327 | BB_END (bb) = end; | |
852c6ec7 | 328 | bb->index = last_basic_block++; |
5e2d947c | 329 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 330 | link_block (bb, after); |
68f9b844 | 331 | SET_BASIC_BLOCK (bb->index, bb); |
6fb5fa3c | 332 | df_bb_refs_record (bb->index, false); |
ba4f7968 | 333 | update_bb_for_insn (bb); |
076c7ab8 | 334 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
335 | |
336 | /* Tag the block so that we know it has been used when considering | |
337 | other basic block notes. */ | |
338 | bb->aux = bb; | |
339 | ||
340 | return bb; | |
341 | } | |
342 | ||
5f0d2358 | 343 | /* Create new basic block consisting of instructions in between HEAD and END |
ffe14686 AM |
344 | and place it to the BB chain after block AFTER. END can be NULL to |
345 | create a new empty basic block before HEAD. Both END and HEAD can be | |
346 | NULL to create basic block at the end of INSN chain. */ | |
ca6c03ca | 347 | |
bc35512f JH |
348 | static basic_block |
349 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 350 | { |
ae50c0cb | 351 | rtx head = (rtx) headp, end = (rtx) endp; |
ca6c03ca | 352 | basic_block bb; |
0b17ab2f | 353 | |
7eca0767 | 354 | /* Grow the basic block array if needed. */ |
9771b263 | 355 | if ((size_t) last_basic_block >= basic_block_info->length ()) |
7eca0767 JH |
356 | { |
357 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; | |
9771b263 | 358 | vec_safe_grow_cleared (basic_block_info, new_size); |
7eca0767 | 359 | } |
0b17ab2f | 360 | |
bf77398c | 361 | n_basic_blocks++; |
ca6c03ca | 362 | |
852c6ec7 | 363 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
364 | bb->aux = NULL; |
365 | return bb; | |
366 | } | |
bc35512f JH |
367 | |
368 | static basic_block | |
369 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
370 | { | |
371 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
372 | ||
bc35512f JH |
373 | return newbb; |
374 | } | |
ca6c03ca JH |
375 | \f |
376 | /* Delete the insns in a (non-live) block. We physically delete every | |
377 | non-deleted-note insn, and update the flow graph appropriately. | |
378 | ||
379 | Return nonzero if we deleted an exception handler. */ | |
380 | ||
381 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
382 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
383 | ||
f0fda11c | 384 | static void |
d329e058 | 385 | rtl_delete_block (basic_block b) |
ca6c03ca | 386 | { |
96370780 | 387 | rtx insn, end; |
ca6c03ca JH |
388 | |
389 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
390 | label for an exception handler which can't be reached. We need |
391 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 392 | insn = BB_HEAD (b); |
ca6c03ca | 393 | |
96370780 | 394 | end = get_last_bb_insn (b); |
ca6c03ca JH |
395 | |
396 | /* Selectively delete the entire chain. */ | |
a813c111 | 397 | BB_HEAD (b) = NULL; |
a7b87f73 ZD |
398 | delete_insn_chain (insn, end, true); |
399 | ||
6fb5fa3c DB |
400 | |
401 | if (dump_file) | |
402 | fprintf (dump_file, "deleting block %d\n", b->index); | |
403 | df_bb_delete (b->index); | |
ca6c03ca JH |
404 | } |
405 | \f | |
852c6ec7 | 406 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
407 | |
408 | void | |
d329e058 | 409 | compute_bb_for_insn (void) |
ca6c03ca | 410 | { |
e0082a72 | 411 | basic_block bb; |
ca6c03ca | 412 | |
e0082a72 | 413 | FOR_EACH_BB (bb) |
ca6c03ca | 414 | { |
a813c111 | 415 | rtx end = BB_END (bb); |
5f0d2358 | 416 | rtx insn; |
ca6c03ca | 417 | |
a813c111 | 418 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 419 | { |
ba4f7968 | 420 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
421 | if (insn == end) |
422 | break; | |
ca6c03ca JH |
423 | } |
424 | } | |
425 | } | |
426 | ||
427 | /* Release the basic_block_for_insn array. */ | |
428 | ||
c2924966 | 429 | unsigned int |
d329e058 | 430 | free_bb_for_insn (void) |
ca6c03ca | 431 | { |
ba4f7968 JH |
432 | rtx insn; |
433 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
4b4bf941 | 434 | if (!BARRIER_P (insn)) |
ba4f7968 | 435 | BLOCK_FOR_INSN (insn) = NULL; |
c2924966 | 436 | return 0; |
ca6c03ca JH |
437 | } |
438 | ||
2a34bece EB |
439 | static unsigned int |
440 | rest_of_pass_free_cfg (void) | |
441 | { | |
442 | #ifdef DELAY_SLOTS | |
443 | /* The resource.c machinery uses DF but the CFG isn't guaranteed to be | |
444 | valid at that point so it would be too late to call df_analyze. */ | |
445 | if (optimize > 0 && flag_delayed_branch) | |
ad78b8a6 EB |
446 | { |
447 | df_note_add_problem (); | |
448 | df_analyze (); | |
449 | } | |
2a34bece EB |
450 | #endif |
451 | ||
452 | free_bb_for_insn (); | |
453 | return 0; | |
454 | } | |
455 | ||
8ddbbcae | 456 | struct rtl_opt_pass pass_free_cfg = |
ef330312 | 457 | { |
8ddbbcae JH |
458 | { |
459 | RTL_PASS, | |
e0a42b0f | 460 | "*free_cfg", /* name */ |
2b4e6bf1 | 461 | OPTGROUP_NONE, /* optinfo_flags */ |
ef330312 | 462 | NULL, /* gate */ |
2a34bece | 463 | rest_of_pass_free_cfg, /* execute */ |
ef330312 PB |
464 | NULL, /* sub */ |
465 | NULL, /* next */ | |
466 | 0, /* static_pass_number */ | |
7072a650 | 467 | TV_NONE, /* tv_id */ |
ef330312 PB |
468 | 0, /* properties_required */ |
469 | 0, /* properties_provided */ | |
470 | PROP_cfg, /* properties_destroyed */ | |
471 | 0, /* todo_flags_start */ | |
472 | 0, /* todo_flags_finish */ | |
8ddbbcae | 473 | } |
ef330312 PB |
474 | }; |
475 | ||
91278841 AP |
476 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
477 | rtx | |
478 | entry_of_function (void) | |
479 | { | |
c22cacf3 | 480 | return (n_basic_blocks > NUM_FIXED_BLOCKS ? |
24bd1a0b | 481 | BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ()); |
91278841 AP |
482 | } |
483 | ||
11b904a1 BS |
484 | /* Emit INSN at the entry point of the function, ensuring that it is only |
485 | executed once per function. */ | |
486 | void | |
487 | emit_insn_at_entry (rtx insn) | |
488 | { | |
489 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->succs); | |
490 | edge e = ei_safe_edge (ei); | |
5419bc7f | 491 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
492 | |
493 | insert_insn_on_edge (insn, e); | |
494 | commit_edge_insertions (); | |
495 | } | |
496 | ||
6c3d0e31 | 497 | /* Update BLOCK_FOR_INSN of insns between BEGIN and END |
b8698a0f | 498 | (or BARRIER if found) and notify df of the bb change. |
6c3d0e31 SP |
499 | The insn chain range is inclusive |
500 | (i.e. both BEGIN and END will be updated. */ | |
ca6c03ca | 501 | |
6c3d0e31 SP |
502 | static void |
503 | update_bb_for_insn_chain (rtx begin, rtx end, basic_block bb) | |
ca6c03ca JH |
504 | { |
505 | rtx insn; | |
506 | ||
6c3d0e31 SP |
507 | end = NEXT_INSN (end); |
508 | for (insn = begin; insn != end; insn = NEXT_INSN (insn)) | |
63642d5a AO |
509 | if (!BARRIER_P (insn)) |
510 | df_insn_change_bb (insn, bb); | |
ca6c03ca | 511 | } |
6c3d0e31 SP |
512 | |
513 | /* Update BLOCK_FOR_INSN of insns in BB to BB, | |
514 | and notify df of the change. */ | |
515 | ||
516 | void | |
517 | update_bb_for_insn (basic_block bb) | |
518 | { | |
519 | update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb); | |
520 | } | |
521 | ||
532aafad SB |
522 | \f |
523 | /* Like active_insn_p, except keep the return value clobber around | |
524 | even after reload. */ | |
525 | ||
526 | static bool | |
527 | flow_active_insn_p (const_rtx insn) | |
528 | { | |
529 | if (active_insn_p (insn)) | |
530 | return true; | |
531 | ||
532 | /* A clobber of the function return value exists for buggy | |
533 | programs that fail to return a value. Its effect is to | |
534 | keep the return value from being live across the entire | |
535 | function. If we allow it to be skipped, we introduce the | |
536 | possibility for register lifetime confusion. */ | |
537 | if (GET_CODE (PATTERN (insn)) == CLOBBER | |
538 | && REG_P (XEXP (PATTERN (insn), 0)) | |
539 | && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0))) | |
540 | return true; | |
541 | ||
542 | return false; | |
543 | } | |
544 | ||
545 | /* Return true if the block has no effect and only forwards control flow to | |
546 | its single destination. */ | |
532aafad SB |
547 | |
548 | bool | |
2407343c | 549 | contains_no_active_insn_p (const_basic_block bb) |
532aafad SB |
550 | { |
551 | rtx insn; | |
552 | ||
553 | if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR | |
554 | || !single_succ_p (bb)) | |
555 | return false; | |
556 | ||
2407343c JR |
557 | for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn)) |
558 | if (INSN_P (insn) && flow_active_insn_p (insn)) | |
559 | return false; | |
560 | ||
561 | return (!INSN_P (insn) | |
562 | || (JUMP_P (insn) && simplejump_p (insn)) | |
563 | || !flow_active_insn_p (insn)); | |
564 | } | |
565 | ||
566 | /* Likewise, but protect loop latches, headers and preheaders. */ | |
567 | /* FIXME: Make this a cfg hook. */ | |
568 | ||
569 | bool | |
570 | forwarder_block_p (const_basic_block bb) | |
571 | { | |
572 | if (!contains_no_active_insn_p (bb)) | |
573 | return false; | |
574 | ||
532aafad SB |
575 | /* Protect loop latches, headers and preheaders. */ |
576 | if (current_loops) | |
577 | { | |
578 | basic_block dest; | |
579 | if (bb->loop_father->header == bb) | |
580 | return false; | |
581 | dest = EDGE_SUCC (bb, 0)->dest; | |
582 | if (dest->loop_father->header == dest) | |
583 | return false; | |
584 | } | |
585 | ||
2407343c | 586 | return true; |
532aafad SB |
587 | } |
588 | ||
589 | /* Return nonzero if we can reach target from src by falling through. */ | |
590 | /* FIXME: Make this a cfg hook. */ | |
591 | ||
592 | bool | |
593 | can_fallthru (basic_block src, basic_block target) | |
594 | { | |
595 | rtx insn = BB_END (src); | |
596 | rtx insn2; | |
597 | edge e; | |
598 | edge_iterator ei; | |
599 | ||
600 | if (target == EXIT_BLOCK_PTR) | |
601 | return true; | |
602 | if (src->next_bb != target) | |
603 | return 0; | |
604 | FOR_EACH_EDGE (e, ei, src->succs) | |
605 | if (e->dest == EXIT_BLOCK_PTR | |
606 | && e->flags & EDGE_FALLTHRU) | |
607 | return 0; | |
608 | ||
609 | insn2 = BB_HEAD (target); | |
610 | if (insn2 && !active_insn_p (insn2)) | |
611 | insn2 = next_active_insn (insn2); | |
612 | ||
613 | /* ??? Later we may add code to move jump tables offline. */ | |
614 | return next_active_insn (insn) == insn2; | |
615 | } | |
616 | ||
617 | /* Return nonzero if we could reach target from src by falling through, | |
618 | if the target was made adjacent. If we already have a fall-through | |
619 | edge to the exit block, we can't do that. */ | |
620 | static bool | |
621 | could_fall_through (basic_block src, basic_block target) | |
622 | { | |
623 | edge e; | |
624 | edge_iterator ei; | |
625 | ||
626 | if (target == EXIT_BLOCK_PTR) | |
627 | return true; | |
628 | FOR_EACH_EDGE (e, ei, src->succs) | |
629 | if (e->dest == EXIT_BLOCK_PTR | |
630 | && e->flags & EDGE_FALLTHRU) | |
631 | return 0; | |
632 | return true; | |
633 | } | |
ca6c03ca | 634 | \f |
ef2be249 RS |
635 | /* Return the NOTE_INSN_BASIC_BLOCK of BB. */ |
636 | rtx | |
637 | bb_note (basic_block bb) | |
638 | { | |
639 | rtx note; | |
640 | ||
641 | note = BB_HEAD (bb); | |
642 | if (LABEL_P (note)) | |
643 | note = NEXT_INSN (note); | |
644 | ||
645 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note)); | |
646 | return note; | |
647 | } | |
648 | ||
6fb5fa3c DB |
649 | /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK |
650 | note associated with the BLOCK. */ | |
651 | ||
652 | static rtx | |
653 | first_insn_after_basic_block_note (basic_block block) | |
654 | { | |
655 | rtx insn; | |
656 | ||
657 | /* Get the first instruction in the block. */ | |
658 | insn = BB_HEAD (block); | |
659 | ||
660 | if (insn == NULL_RTX) | |
661 | return NULL_RTX; | |
662 | if (LABEL_P (insn)) | |
663 | insn = NEXT_INSN (insn); | |
664 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
665 | ||
666 | return NEXT_INSN (insn); | |
667 | } | |
668 | ||
f470c378 ZD |
669 | /* Creates a new basic block just after basic block B by splitting |
670 | everything after specified instruction I. */ | |
ca6c03ca | 671 | |
f470c378 | 672 | static basic_block |
d329e058 | 673 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
674 | { |
675 | basic_block new_bb; | |
ae50c0cb | 676 | rtx insn = (rtx) insnp; |
f470c378 | 677 | edge e; |
628f6a4e | 678 | edge_iterator ei; |
ca6c03ca | 679 | |
f470c378 ZD |
680 | if (!insn) |
681 | { | |
682 | insn = first_insn_after_basic_block_note (bb); | |
683 | ||
684 | if (insn) | |
b5b8b0ac AO |
685 | { |
686 | rtx next = insn; | |
687 | ||
688 | insn = PREV_INSN (insn); | |
689 | ||
690 | /* If the block contains only debug insns, insn would have | |
691 | been NULL in a non-debug compilation, and then we'd end | |
692 | up emitting a DELETED note. For -fcompare-debug | |
693 | stability, emit the note too. */ | |
694 | if (insn != BB_END (bb) | |
695 | && DEBUG_INSN_P (next) | |
696 | && DEBUG_INSN_P (BB_END (bb))) | |
697 | { | |
698 | while (next != BB_END (bb) && DEBUG_INSN_P (next)) | |
699 | next = NEXT_INSN (next); | |
700 | ||
701 | if (next == BB_END (bb)) | |
702 | emit_note_after (NOTE_INSN_DELETED, next); | |
703 | } | |
704 | } | |
f470c378 ZD |
705 | else |
706 | insn = get_last_insn (); | |
707 | } | |
708 | ||
709 | /* We probably should check type of the insn so that we do not create | |
710 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
711 | bother. */ | |
712 | if (insn == BB_END (bb)) | |
713 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
714 | |
715 | /* Create the new basic block. */ | |
a813c111 | 716 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 717 | BB_COPY_PARTITION (new_bb, bb); |
a813c111 | 718 | BB_END (bb) = insn; |
ca6c03ca JH |
719 | |
720 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
721 | new_bb->succs = bb->succs; |
722 | bb->succs = NULL; | |
723 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
724 | e->src = new_bb; |
725 | ||
6fb5fa3c DB |
726 | /* The new block starts off being dirty. */ |
727 | df_set_bb_dirty (bb); | |
f470c378 | 728 | return new_bb; |
bc35512f JH |
729 | } |
730 | ||
9be94227 EB |
731 | /* Return true if the single edge between blocks A and B is the only place |
732 | in RTL which holds some unique locus. */ | |
733 | ||
734 | static bool | |
735 | unique_locus_on_edge_between_p (basic_block a, basic_block b) | |
736 | { | |
5368224f | 737 | const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
738 | rtx insn, end; |
739 | ||
2f13f2de | 740 | if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION) |
9be94227 EB |
741 | return false; |
742 | ||
743 | /* First scan block A backward. */ | |
744 | insn = BB_END (a); | |
745 | end = PREV_INSN (BB_HEAD (a)); | |
5368224f | 746 | while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
9be94227 EB |
747 | insn = PREV_INSN (insn); |
748 | ||
5368224f | 749 | if (insn != end && INSN_LOCATION (insn) == goto_locus) |
9be94227 EB |
750 | return false; |
751 | ||
752 | /* Then scan block B forward. */ | |
753 | insn = BB_HEAD (b); | |
754 | if (insn) | |
755 | { | |
756 | end = NEXT_INSN (BB_END (b)); | |
757 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
758 | insn = NEXT_INSN (insn); | |
759 | ||
5368224f DC |
760 | if (insn != end && INSN_HAS_LOCATION (insn) |
761 | && INSN_LOCATION (insn) == goto_locus) | |
9be94227 EB |
762 | return false; |
763 | } | |
764 | ||
765 | return true; | |
766 | } | |
767 | ||
768 | /* If the single edge between blocks A and B is the only place in RTL which | |
769 | holds some unique locus, emit a nop with that locus between the blocks. */ | |
770 | ||
771 | static void | |
772 | emit_nop_for_unique_locus_between (basic_block a, basic_block b) | |
773 | { | |
774 | if (!unique_locus_on_edge_between_p (a, b)) | |
775 | return; | |
776 | ||
777 | BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a); | |
5368224f | 778 | INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus; |
9be94227 EB |
779 | } |
780 | ||
ca6c03ca | 781 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 782 | are already contiguous. */ |
ca6c03ca | 783 | |
bc35512f JH |
784 | static void |
785 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 786 | { |
a813c111 | 787 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca | 788 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
b5b8b0ac | 789 | rtx b_debug_start = b_end, b_debug_end = b_end; |
50a36e42 | 790 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
ca6c03ca JH |
791 | int b_empty = 0; |
792 | ||
6fb5fa3c | 793 | if (dump_file) |
50a36e42 EB |
794 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
795 | a->index); | |
6fb5fa3c | 796 | |
b5b8b0ac AO |
797 | while (DEBUG_INSN_P (b_end)) |
798 | b_end = PREV_INSN (b_debug_start = b_end); | |
799 | ||
ca6c03ca | 800 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 801 | if (LABEL_P (b_head)) |
ca6c03ca JH |
802 | { |
803 | /* Detect basic blocks with nothing but a label. This can happen | |
804 | in particular at the end of a function. */ | |
805 | if (b_head == b_end) | |
806 | b_empty = 1; | |
5f0d2358 | 807 | |
ca6c03ca JH |
808 | del_first = del_last = b_head; |
809 | b_head = NEXT_INSN (b_head); | |
810 | } | |
811 | ||
5f0d2358 RK |
812 | /* Delete the basic block note and handle blocks containing just that |
813 | note. */ | |
ca6c03ca JH |
814 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
815 | { | |
816 | if (b_head == b_end) | |
817 | b_empty = 1; | |
818 | if (! del_last) | |
819 | del_first = b_head; | |
5f0d2358 | 820 | |
ca6c03ca JH |
821 | del_last = b_head; |
822 | b_head = NEXT_INSN (b_head); | |
823 | } | |
824 | ||
825 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 826 | if (JUMP_P (a_end)) |
ca6c03ca JH |
827 | { |
828 | rtx prev; | |
829 | ||
830 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 831 | if (!NOTE_P (prev) |
a38e7aa5 | 832 | || NOTE_INSN_BASIC_BLOCK_P (prev) |
a813c111 | 833 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
834 | break; |
835 | ||
836 | del_first = a_end; | |
837 | ||
838 | #ifdef HAVE_cc0 | |
839 | /* If this was a conditional jump, we need to also delete | |
840 | the insn that set cc0. */ | |
841 | if (only_sets_cc0_p (prev)) | |
842 | { | |
843 | rtx tmp = prev; | |
5f0d2358 | 844 | |
ca6c03ca JH |
845 | prev = prev_nonnote_insn (prev); |
846 | if (!prev) | |
a813c111 | 847 | prev = BB_HEAD (a); |
ca6c03ca JH |
848 | del_first = tmp; |
849 | } | |
850 | #endif | |
851 | ||
852 | a_end = PREV_INSN (del_first); | |
853 | } | |
4b4bf941 | 854 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
855 | del_first = NEXT_INSN (a_end); |
856 | ||
ca6c03ca JH |
857 | /* Delete everything marked above as well as crap that might be |
858 | hanging out between the two blocks. */ | |
9be94227 EB |
859 | BB_END (a) = a_end; |
860 | BB_HEAD (b) = b_empty ? NULL_RTX : b_head; | |
a7b87f73 | 861 | delete_insn_chain (del_first, del_last, true); |
ca6c03ca | 862 | |
9be94227 EB |
863 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
864 | some unique locus, emit a nop with that locus in between. */ | |
865 | if (!optimize) | |
866 | { | |
867 | emit_nop_for_unique_locus_between (a, b); | |
868 | a_end = BB_END (a); | |
869 | } | |
870 | ||
ca6c03ca JH |
871 | /* Reassociate the insns of B with A. */ |
872 | if (!b_empty) | |
873 | { | |
b5b8b0ac | 874 | update_bb_for_insn_chain (a_end, b_debug_end, a); |
5f0d2358 | 875 | |
9be94227 EB |
876 | BB_END (a) = b_debug_end; |
877 | BB_HEAD (b) = NULL_RTX; | |
b5b8b0ac AO |
878 | } |
879 | else if (b_end != b_debug_end) | |
880 | { | |
881 | /* Move any deleted labels and other notes between the end of A | |
882 | and the debug insns that make up B after the debug insns, | |
883 | bringing the debug insns into A while keeping the notes after | |
884 | the end of A. */ | |
885 | if (NEXT_INSN (a_end) != b_debug_start) | |
886 | reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start), | |
887 | b_debug_end); | |
888 | update_bb_for_insn_chain (b_debug_start, b_debug_end, a); | |
9be94227 | 889 | BB_END (a) = b_debug_end; |
ca6c03ca | 890 | } |
5f0d2358 | 891 | |
6fb5fa3c | 892 | df_bb_delete (b->index); |
50a36e42 EB |
893 | |
894 | /* If B was a forwarder block, propagate the locus on the edge. */ | |
fbc68f2a DC |
895 | if (forwarder_p |
896 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) | |
50a36e42 EB |
897 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
898 | ||
899 | if (dump_file) | |
900 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); | |
ca6c03ca | 901 | } |
bc35512f | 902 | |
6fb5fa3c | 903 | |
bc35512f | 904 | /* Return true when block A and B can be merged. */ |
9678086d | 905 | |
b48d0358 DN |
906 | static bool |
907 | rtl_can_merge_blocks (basic_block a, basic_block b) | |
bc35512f | 908 | { |
750054a2 CT |
909 | /* If we are partitioning hot/cold basic blocks, we don't want to |
910 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
911 | and cold sections. |
912 | ||
8e8d5162 | 913 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
914 | be optimizable (or blocks that appear to be mergeable), but which really |
915 | must be left untouched (they are required to make it safely across | |
916 | partition boundaries). See the comments at the top of | |
8e8d5162 | 917 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 918 | |
87c8b4be | 919 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 920 | return false; |
750054a2 | 921 | |
7d776ee2 RG |
922 | /* Protect the loop latches. */ |
923 | if (current_loops && b->loop_father->latch == b) | |
924 | return false; | |
925 | ||
bc35512f | 926 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
927 | return (single_succ_p (a) |
928 | && single_succ (a) == b | |
929 | && single_pred_p (b) | |
628f6a4e | 930 | && a != b |
bc35512f | 931 | /* Must be simple edge. */ |
c5cbcccf | 932 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f JH |
933 | && a->next_bb == b |
934 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR | |
935 | /* If the jump insn has side effects, | |
936 | we can't kill the edge. */ | |
4b4bf941 | 937 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 938 | || (reload_completed |
a813c111 | 939 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 940 | } |
ca6c03ca | 941 | \f |
5f0d2358 RK |
942 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
943 | exist. */ | |
ca6c03ca JH |
944 | |
945 | rtx | |
d329e058 | 946 | block_label (basic_block block) |
ca6c03ca JH |
947 | { |
948 | if (block == EXIT_BLOCK_PTR) | |
949 | return NULL_RTX; | |
5f0d2358 | 950 | |
4b4bf941 | 951 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 952 | { |
a813c111 | 953 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 954 | } |
5f0d2358 | 955 | |
a813c111 | 956 | return BB_HEAD (block); |
ca6c03ca JH |
957 | } |
958 | ||
959 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
960 | instruction by unconditional jump or removing jump completely. This can |
961 | apply only if all edges now point to the same block. The parameters and | |
962 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 963 | |
6de9cd9a | 964 | edge |
bc35512f | 965 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
966 | { |
967 | basic_block src = e->src; | |
a813c111 | 968 | rtx insn = BB_END (src), kill_from; |
e1233a7d | 969 | rtx set; |
ca6c03ca | 970 | int fallthru = 0; |
750054a2 CT |
971 | |
972 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
973 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
974 | and cold sections. |
975 | ||
976 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
977 | be optimizable (or blocks that appear to be mergeable), but which really |
978 | must be left untouched (they are required to make it safely across | |
979 | partition boundaries). See the comments at the top of | |
8e8d5162 | 980 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 981 | |
87c8b4be CT |
982 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) |
983 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
9cf84a3c | 984 | return NULL; |
750054a2 | 985 | |
6a66a8a7 KH |
986 | /* We can replace or remove a complex jump only when we have exactly |
987 | two edges. Also, if we have exactly one outgoing edge, we can | |
988 | redirect that. */ | |
989 | if (EDGE_COUNT (src->succs) >= 3 | |
990 | /* Verify that all targets will be TARGET. Specifically, the | |
991 | edge that is not E must also go to TARGET. */ | |
992 | || (EDGE_COUNT (src->succs) == 2 | |
993 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
994 | return NULL; | |
5f0d2358 | 995 | |
6a66a8a7 | 996 | if (!onlyjump_p (insn)) |
6de9cd9a | 997 | return NULL; |
3348b696 | 998 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 999 | return NULL; |
ca6c03ca JH |
1000 | |
1001 | /* Avoid removing branch with side effects. */ | |
1002 | set = single_set (insn); | |
1003 | if (!set || side_effects_p (set)) | |
6de9cd9a | 1004 | return NULL; |
ca6c03ca JH |
1005 | |
1006 | /* In case we zap a conditional jump, we'll need to kill | |
1007 | the cc0 setter too. */ | |
1008 | kill_from = insn; | |
1009 | #ifdef HAVE_cc0 | |
9caea4a7 RS |
1010 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
1011 | && only_sets_cc0_p (PREV_INSN (insn))) | |
ca6c03ca JH |
1012 | kill_from = PREV_INSN (insn); |
1013 | #endif | |
1014 | ||
1015 | /* See if we can create the fallthru edge. */ | |
bc35512f | 1016 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 1017 | { |
c263766c RH |
1018 | if (dump_file) |
1019 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
1020 | fallthru = 1; |
1021 | ||
eaec9b3d | 1022 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
1023 | if (in_cfglayout) |
1024 | { | |
bcc708fc | 1025 | rtx insn = BB_FOOTER (src); |
bc35512f | 1026 | |
a7b87f73 | 1027 | delete_insn_chain (kill_from, BB_END (src), false); |
bc35512f JH |
1028 | |
1029 | /* Remove barriers but keep jumptables. */ | |
1030 | while (insn) | |
1031 | { | |
4b4bf941 | 1032 | if (BARRIER_P (insn)) |
bc35512f JH |
1033 | { |
1034 | if (PREV_INSN (insn)) | |
1035 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
1036 | else | |
bcc708fc | 1037 | BB_FOOTER (src) = NEXT_INSN (insn); |
bc35512f JH |
1038 | if (NEXT_INSN (insn)) |
1039 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
1040 | } | |
4b4bf941 | 1041 | if (LABEL_P (insn)) |
bc35512f JH |
1042 | break; |
1043 | insn = NEXT_INSN (insn); | |
1044 | } | |
1045 | } | |
1046 | else | |
a7b87f73 ZD |
1047 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)), |
1048 | false); | |
ca6c03ca | 1049 | } |
5f0d2358 | 1050 | |
ca6c03ca JH |
1051 | /* If this already is simplejump, redirect it. */ |
1052 | else if (simplejump_p (insn)) | |
1053 | { | |
1054 | if (e->dest == target) | |
6de9cd9a | 1055 | return NULL; |
c263766c RH |
1056 | if (dump_file) |
1057 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 1058 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
1059 | if (!redirect_jump (insn, block_label (target), 0)) |
1060 | { | |
341c100f NS |
1061 | gcc_assert (target == EXIT_BLOCK_PTR); |
1062 | return NULL; | |
6ee3c8e4 | 1063 | } |
ca6c03ca | 1064 | } |
5f0d2358 | 1065 | |
6ee3c8e4 JJ |
1066 | /* Cannot do anything for target exit block. */ |
1067 | else if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 1068 | return NULL; |
6ee3c8e4 | 1069 | |
ca6c03ca JH |
1070 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
1071 | else | |
1072 | { | |
1073 | rtx target_label = block_label (target); | |
eb5b8ad4 | 1074 | rtx barrier, label, table; |
ca6c03ca | 1075 | |
a7102479 | 1076 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
a813c111 | 1077 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 1078 | LABEL_NUSES (target_label)++; |
c263766c RH |
1079 | if (dump_file) |
1080 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 1081 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 1082 | |
4da2eb6b | 1083 | |
ba4807a0 LB |
1084 | delete_insn_chain (kill_from, insn, false); |
1085 | ||
4da2eb6b RH |
1086 | /* Recognize a tablejump that we are converting to a |
1087 | simple jump and remove its associated CODE_LABEL | |
1088 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
ba4807a0 LB |
1089 | if (tablejump_p (insn, &label, &table)) |
1090 | delete_insn_chain (label, table, false); | |
eb5b8ad4 | 1091 | |
a813c111 | 1092 | barrier = next_nonnote_insn (BB_END (src)); |
4b4bf941 | 1093 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 1094 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
1095 | else |
1096 | { | |
a813c111 | 1097 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
1098 | { |
1099 | /* Move the jump before barrier so that the notes | |
1100 | which originally were or were created before jump table are | |
1101 | inside the basic block. */ | |
a813c111 | 1102 | rtx new_insn = BB_END (src); |
5d693491 | 1103 | |
6c3d0e31 SP |
1104 | update_bb_for_insn_chain (NEXT_INSN (BB_END (src)), |
1105 | PREV_INSN (barrier), src); | |
5d693491 JZ |
1106 | |
1107 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
1108 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
1109 | ||
1110 | NEXT_INSN (new_insn) = barrier; | |
1111 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
1112 | ||
1113 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
1114 | PREV_INSN (barrier) = new_insn; | |
1115 | } | |
1116 | } | |
ca6c03ca JH |
1117 | } |
1118 | ||
1119 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 1120 | if (!single_succ_p (src)) |
628f6a4e | 1121 | remove_edge (e); |
c5cbcccf | 1122 | gcc_assert (single_succ_p (src)); |
628f6a4e | 1123 | |
c5cbcccf | 1124 | e = single_succ_edge (src); |
ca6c03ca JH |
1125 | if (fallthru) |
1126 | e->flags = EDGE_FALLTHRU; | |
1127 | else | |
1128 | e->flags = 0; | |
5f0d2358 | 1129 | |
ca6c03ca JH |
1130 | e->probability = REG_BR_PROB_BASE; |
1131 | e->count = src->count; | |
1132 | ||
ca6c03ca JH |
1133 | if (e->dest != target) |
1134 | redirect_edge_succ (e, target); | |
6de9cd9a | 1135 | return e; |
ca6c03ca JH |
1136 | } |
1137 | ||
4e3825db MM |
1138 | /* Subroutine of redirect_branch_edge that tries to patch the jump |
1139 | instruction INSN so that it reaches block NEW. Do this | |
1140 | only when it originally reached block OLD. Return true if this | |
1141 | worked or the original target wasn't OLD, return false if redirection | |
1142 | doesn't work. */ | |
1143 | ||
1144 | static bool | |
1145 | patch_jump_insn (rtx insn, rtx old_label, basic_block new_bb) | |
ca6c03ca JH |
1146 | { |
1147 | rtx tmp; | |
ca6c03ca | 1148 | /* Recognize a tablejump and adjust all matching cases. */ |
e1233a7d | 1149 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
1150 | { |
1151 | rtvec vec; | |
1152 | int j; | |
4e3825db | 1153 | rtx new_label = block_label (new_bb); |
ca6c03ca | 1154 | |
4e3825db MM |
1155 | if (new_bb == EXIT_BLOCK_PTR) |
1156 | return false; | |
ca6c03ca JH |
1157 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
1158 | vec = XVEC (PATTERN (tmp), 0); | |
1159 | else | |
1160 | vec = XVEC (PATTERN (tmp), 1); | |
1161 | ||
1162 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
1163 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
1164 | { | |
1165 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
1166 | --LABEL_NUSES (old_label); | |
1167 | ++LABEL_NUSES (new_label); | |
1168 | } | |
1169 | ||
f9da5064 | 1170 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
1171 | if ((tmp = single_set (insn)) != NULL |
1172 | && SET_DEST (tmp) == pc_rtx | |
1173 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
1174 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
1175 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
1176 | { | |
4c33cb26 | 1177 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
1178 | new_label); |
1179 | --LABEL_NUSES (old_label); | |
1180 | ++LABEL_NUSES (new_label); | |
1181 | } | |
1182 | } | |
1c384bf1 RH |
1183 | else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL) |
1184 | { | |
1185 | int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp); | |
1186 | rtx new_label, note; | |
1187 | ||
1188 | if (new_bb == EXIT_BLOCK_PTR) | |
1189 | return false; | |
1190 | new_label = block_label (new_bb); | |
1191 | ||
1192 | for (i = 0; i < n; ++i) | |
1193 | { | |
1194 | rtx old_ref = ASM_OPERANDS_LABEL (tmp, i); | |
1195 | gcc_assert (GET_CODE (old_ref) == LABEL_REF); | |
1196 | if (XEXP (old_ref, 0) == old_label) | |
1197 | { | |
1198 | ASM_OPERANDS_LABEL (tmp, i) | |
1199 | = gen_rtx_LABEL_REF (Pmode, new_label); | |
1200 | --LABEL_NUSES (old_label); | |
1201 | ++LABEL_NUSES (new_label); | |
1202 | } | |
1203 | } | |
1204 | ||
1205 | if (JUMP_LABEL (insn) == old_label) | |
1206 | { | |
1207 | JUMP_LABEL (insn) = new_label; | |
1208 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1209 | if (note) | |
1210 | remove_note (insn, note); | |
1211 | } | |
1212 | else | |
1213 | { | |
1214 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1215 | if (note) | |
1216 | remove_note (insn, note); | |
1217 | if (JUMP_LABEL (insn) != new_label | |
1218 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1219 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1220 | } | |
3b5fda81 JJ |
1221 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) |
1222 | != NULL_RTX) | |
1223 | XEXP (note, 0) = new_label; | |
1c384bf1 | 1224 | } |
ca6c03ca JH |
1225 | else |
1226 | { | |
1227 | /* ?? We may play the games with moving the named labels from | |
1228 | one basic block to the other in case only one computed_jump is | |
1229 | available. */ | |
5f0d2358 RK |
1230 | if (computed_jump_p (insn) |
1231 | /* A return instruction can't be redirected. */ | |
1232 | || returnjump_p (insn)) | |
4e3825db | 1233 | return false; |
6ee3c8e4 | 1234 | |
4e3825db | 1235 | if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label) |
6ee3c8e4 | 1236 | { |
4e3825db MM |
1237 | /* If the insn doesn't go where we think, we're confused. */ |
1238 | gcc_assert (JUMP_LABEL (insn) == old_label); | |
1239 | ||
1240 | /* If the substitution doesn't succeed, die. This can happen | |
1241 | if the back end emitted unrecognizable instructions or if | |
1242 | target is exit block on some arches. */ | |
1243 | if (!redirect_jump (insn, block_label (new_bb), 0)) | |
1244 | { | |
1245 | gcc_assert (new_bb == EXIT_BLOCK_PTR); | |
1246 | return false; | |
1247 | } | |
6ee3c8e4 | 1248 | } |
ca6c03ca | 1249 | } |
4e3825db MM |
1250 | return true; |
1251 | } | |
1252 | ||
1253 | ||
1254 | /* Redirect edge representing branch of (un)conditional jump or tablejump, | |
1255 | NULL on failure */ | |
1256 | static edge | |
1257 | redirect_branch_edge (edge e, basic_block target) | |
1258 | { | |
1259 | rtx old_label = BB_HEAD (e->dest); | |
1260 | basic_block src = e->src; | |
1261 | rtx insn = BB_END (src); | |
1262 | ||
1263 | /* We can only redirect non-fallthru edges of jump insn. */ | |
1264 | if (e->flags & EDGE_FALLTHRU) | |
1265 | return NULL; | |
1266 | else if (!JUMP_P (insn) && !currently_expanding_to_rtl) | |
1267 | return NULL; | |
1268 | ||
1269 | if (!currently_expanding_to_rtl) | |
1270 | { | |
1271 | if (!patch_jump_insn (insn, old_label, target)) | |
1272 | return NULL; | |
1273 | } | |
1274 | else | |
1275 | /* When expanding this BB might actually contain multiple | |
1276 | jumps (i.e. not yet split by find_many_sub_basic_blocks). | |
1277 | Redirect all of those that match our label. */ | |
0f346928 | 1278 | FOR_BB_INSNS (src, insn) |
4e3825db MM |
1279 | if (JUMP_P (insn) && !patch_jump_insn (insn, old_label, target)) |
1280 | return NULL; | |
ca6c03ca | 1281 | |
c263766c RH |
1282 | if (dump_file) |
1283 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 1284 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 1285 | |
ca6c03ca | 1286 | if (e->dest != target) |
6de9cd9a | 1287 | e = redirect_edge_succ_nodup (e, target); |
6fb5fa3c | 1288 | |
6de9cd9a | 1289 | return e; |
bc35512f JH |
1290 | } |
1291 | ||
1292 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on | |
1293 | expense of adding new instructions or reordering basic blocks. | |
1294 | ||
1295 | Function can be also called with edge destination equivalent to the TARGET. | |
1296 | Then it should try the simplifications and do nothing if none is possible. | |
1297 | ||
6de9cd9a DN |
1298 | Return edge representing the branch if transformation succeeded. Return NULL |
1299 | on failure. | |
1300 | We still return NULL in case E already destinated TARGET and we didn't | |
1301 | managed to simplify instruction stream. */ | |
bc35512f | 1302 | |
6de9cd9a | 1303 | static edge |
5671bf27 | 1304 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 1305 | { |
6de9cd9a | 1306 | edge ret; |
f345f21a JH |
1307 | basic_block src = e->src; |
1308 | ||
bc35512f | 1309 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 1310 | return NULL; |
bc35512f | 1311 | |
3348b696 | 1312 | if (e->dest == target) |
6de9cd9a | 1313 | return e; |
3348b696 | 1314 | |
6de9cd9a | 1315 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a | 1316 | { |
6fb5fa3c | 1317 | df_set_bb_dirty (src); |
6de9cd9a | 1318 | return ret; |
f345f21a | 1319 | } |
bc35512f | 1320 | |
6de9cd9a DN |
1321 | ret = redirect_branch_edge (e, target); |
1322 | if (!ret) | |
1323 | return NULL; | |
5f0d2358 | 1324 | |
6fb5fa3c | 1325 | df_set_bb_dirty (src); |
6de9cd9a | 1326 | return ret; |
ca6c03ca JH |
1327 | } |
1328 | ||
4fe9b91c | 1329 | /* Like force_nonfallthru below, but additionally performs redirection |
26898771 BS |
1330 | Used by redirect_edge_and_branch_force. JUMP_LABEL is used only |
1331 | when redirecting to the EXIT_BLOCK, it is either ret_rtx or | |
1332 | simple_return_rtx, indicating which kind of returnjump to create. | |
1333 | It should be NULL otherwise. */ | |
ca6c03ca | 1334 | |
dc0ff1c8 | 1335 | basic_block |
26898771 | 1336 | force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label) |
ca6c03ca | 1337 | { |
a3716585 | 1338 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
1339 | rtx note; |
1340 | edge new_edge; | |
a3716585 | 1341 | int abnormal_edge_flags = 0; |
a3e6a37b | 1342 | bool asm_goto_edge = false; |
7241571e | 1343 | int loc; |
ca6c03ca | 1344 | |
cb9a1d9b JH |
1345 | /* In the case the last instruction is conditional jump to the next |
1346 | instruction, first redirect the jump itself and then continue | |
b20b352b | 1347 | by creating a basic block afterwards to redirect fallthru edge. */ |
cb9a1d9b | 1348 | if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR |
a813c111 | 1349 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 1350 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
1351 | { |
1352 | rtx note; | |
58e6ae30 | 1353 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1354 | bool redirected; |
cb9a1d9b | 1355 | |
341c100f NS |
1356 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1357 | gcc_assert (redirected); | |
c22cacf3 | 1358 | |
a813c111 | 1359 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1360 | if (note) |
1361 | { | |
1362 | int prob = INTVAL (XEXP (note, 0)); | |
1363 | ||
1364 | b->probability = prob; | |
1365 | b->count = e->count * prob / REG_BR_PROB_BASE; | |
1366 | e->probability -= e->probability; | |
1367 | e->count -= b->count; | |
1368 | if (e->probability < 0) | |
1369 | e->probability = 0; | |
1370 | if (e->count < 0) | |
1371 | e->count = 0; | |
1372 | } | |
1373 | } | |
1374 | ||
ca6c03ca | 1375 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1376 | { |
1377 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1378 | edge. | |
1379 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1380 | one and create separate abnormal edge to original destination. |
a3716585 | 1381 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1382 | gcc_assert (e->dest == target); |
ee44c28d SB |
1383 | abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU; |
1384 | e->flags &= EDGE_FALLTHRU; | |
a3716585 | 1385 | } |
341c100f | 1386 | else |
24c545ff | 1387 | { |
341c100f NS |
1388 | gcc_assert (e->flags & EDGE_FALLTHRU); |
1389 | if (e->src == ENTRY_BLOCK_PTR) | |
1390 | { | |
1391 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1392 | at the start of the function which we use to add the new |
1393 | jump. */ | |
1394 | edge tmp; | |
1395 | edge_iterator ei; | |
1396 | bool found = false; | |
c22cacf3 | 1397 | |
628f6a4e | 1398 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, ENTRY_BLOCK_PTR); |
c22cacf3 | 1399 | |
341c100f NS |
1400 | /* Change the existing edge's source to be the new block, and add |
1401 | a new edge from the entry block to the new block. */ | |
1402 | e->src = bb; | |
628f6a4e BE |
1403 | for (ei = ei_start (ENTRY_BLOCK_PTR->succs); (tmp = ei_safe_edge (ei)); ) |
1404 | { | |
1405 | if (tmp == e) | |
1406 | { | |
9771b263 | 1407 | ENTRY_BLOCK_PTR->succs->unordered_remove (ei.index); |
628f6a4e BE |
1408 | found = true; |
1409 | break; | |
1410 | } | |
1411 | else | |
1412 | ei_next (&ei); | |
1413 | } | |
c22cacf3 | 1414 | |
628f6a4e | 1415 | gcc_assert (found); |
c22cacf3 | 1416 | |
9771b263 | 1417 | vec_safe_push (bb->succs, e); |
341c100f NS |
1418 | make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU); |
1419 | } | |
24c545ff BS |
1420 | } |
1421 | ||
a3e6a37b | 1422 | /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs |
891ca07d | 1423 | don't point to the target or fallthru label. */ |
a3e6a37b JJ |
1424 | if (JUMP_P (BB_END (e->src)) |
1425 | && target != EXIT_BLOCK_PTR | |
a3e6a37b JJ |
1426 | && (e->flags & EDGE_FALLTHRU) |
1427 | && (note = extract_asm_operands (PATTERN (BB_END (e->src))))) | |
ca6c03ca | 1428 | { |
a3e6a37b | 1429 | int i, n = ASM_OPERANDS_LABEL_LENGTH (note); |
5d68b7e6 | 1430 | bool adjust_jump_target = false; |
a3e6a37b JJ |
1431 | |
1432 | for (i = 0; i < n; ++i) | |
891ca07d JJ |
1433 | { |
1434 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest)) | |
5d68b7e6 JJ |
1435 | { |
1436 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--; | |
1437 | XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target); | |
1438 | LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++; | |
1439 | adjust_jump_target = true; | |
1440 | } | |
891ca07d | 1441 | if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target)) |
a3e6a37b | 1442 | asm_goto_edge = true; |
891ca07d | 1443 | } |
5d68b7e6 JJ |
1444 | if (adjust_jump_target) |
1445 | { | |
1446 | rtx insn = BB_END (e->src), note; | |
1447 | rtx old_label = BB_HEAD (e->dest); | |
1448 | rtx new_label = BB_HEAD (target); | |
1449 | ||
1450 | if (JUMP_LABEL (insn) == old_label) | |
1451 | { | |
1452 | JUMP_LABEL (insn) = new_label; | |
1453 | note = find_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1454 | if (note) | |
1455 | remove_note (insn, note); | |
1456 | } | |
1457 | else | |
1458 | { | |
1459 | note = find_reg_note (insn, REG_LABEL_TARGET, old_label); | |
1460 | if (note) | |
1461 | remove_note (insn, note); | |
1462 | if (JUMP_LABEL (insn) != new_label | |
1463 | && !find_reg_note (insn, REG_LABEL_TARGET, new_label)) | |
1464 | add_reg_note (insn, REG_LABEL_TARGET, new_label); | |
1465 | } | |
1466 | while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label)) | |
1467 | != NULL_RTX) | |
1468 | XEXP (note, 0) = new_label; | |
1469 | } | |
a3e6a37b JJ |
1470 | } |
1471 | ||
1472 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge) | |
1473 | { | |
1474 | gcov_type count = e->count; | |
1475 | int probability = e->probability; | |
ca6c03ca | 1476 | /* Create the new structures. */ |
31a78298 | 1477 | |
79019985 RH |
1478 | /* If the old block ended with a tablejump, skip its table |
1479 | by searching forward from there. Otherwise start searching | |
1480 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1481 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1482 | note = BB_END (e->src); | |
31a78298 RH |
1483 | note = NEXT_INSN (note); |
1484 | ||
31a78298 | 1485 | jump_block = create_basic_block (note, NULL, e->src); |
a3e6a37b | 1486 | jump_block->count = count; |
ca6c03ca | 1487 | jump_block->frequency = EDGE_FREQUENCY (e); |
ca6c03ca | 1488 | |
750054a2 CT |
1489 | /* Make sure new block ends up in correct hot/cold section. */ |
1490 | ||
076c7ab8 | 1491 | BB_COPY_PARTITION (jump_block, e->src); |
9fb32434 | 1492 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1493 | && targetm_common.have_named_sections |
87c8b4be CT |
1494 | && JUMP_P (BB_END (jump_block)) |
1495 | && !any_condjump_p (BB_END (jump_block)) | |
1496 | && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING)) | |
65c5f2a6 | 1497 | add_reg_note (BB_END (jump_block), REG_CROSSING_JUMP, NULL_RTX); |
c22cacf3 | 1498 | |
ca6c03ca JH |
1499 | /* Wire edge in. */ |
1500 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
a3e6a37b JJ |
1501 | new_edge->probability = probability; |
1502 | new_edge->count = count; | |
ca6c03ca JH |
1503 | |
1504 | /* Redirect old edge. */ | |
1505 | redirect_edge_pred (e, jump_block); | |
1506 | e->probability = REG_BR_PROB_BASE; | |
1507 | ||
a3e6a37b JJ |
1508 | /* If asm goto has any label refs to target's label, |
1509 | add also edge from asm goto bb to target. */ | |
1510 | if (asm_goto_edge) | |
1511 | { | |
1512 | new_edge->probability /= 2; | |
1513 | new_edge->count /= 2; | |
1514 | jump_block->count /= 2; | |
1515 | jump_block->frequency /= 2; | |
1516 | new_edge = make_edge (new_edge->src, target, | |
1517 | e->flags & ~EDGE_FALLTHRU); | |
1518 | new_edge->probability = probability - probability / 2; | |
1519 | new_edge->count = count - count / 2; | |
1520 | } | |
1521 | ||
ca6c03ca JH |
1522 | new_bb = jump_block; |
1523 | } | |
1524 | else | |
1525 | jump_block = e->src; | |
5f0d2358 | 1526 | |
2f13f2de | 1527 | loc = e->goto_locus; |
ca6c03ca JH |
1528 | e->flags &= ~EDGE_FALLTHRU; |
1529 | if (target == EXIT_BLOCK_PTR) | |
1530 | { | |
26898771 BS |
1531 | if (jump_label == ret_rtx) |
1532 | { | |
cf22ce3c | 1533 | #ifdef HAVE_return |
26898771 | 1534 | emit_jump_insn_after_setloc (gen_return (), BB_END (jump_block), loc); |
cf22ce3c | 1535 | #else |
26898771 | 1536 | gcc_unreachable (); |
cf22ce3c | 1537 | #endif |
26898771 BS |
1538 | } |
1539 | else | |
1540 | { | |
1541 | gcc_assert (jump_label == simple_return_rtx); | |
1542 | #ifdef HAVE_simple_return | |
1543 | emit_jump_insn_after_setloc (gen_simple_return (), | |
1544 | BB_END (jump_block), loc); | |
1545 | #else | |
1546 | gcc_unreachable (); | |
1547 | #endif | |
1548 | } | |
387748de | 1549 | set_return_jump_label (BB_END (jump_block)); |
ca6c03ca JH |
1550 | } |
1551 | else | |
1552 | { | |
1553 | rtx label = block_label (target); | |
7241571e | 1554 | emit_jump_insn_after_setloc (gen_jump (label), BB_END (jump_block), loc); |
a813c111 | 1555 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1556 | LABEL_NUSES (label)++; |
1557 | } | |
5f0d2358 | 1558 | |
a813c111 | 1559 | emit_barrier_after (BB_END (jump_block)); |
ca6c03ca JH |
1560 | redirect_edge_succ_nodup (e, target); |
1561 | ||
a3716585 JH |
1562 | if (abnormal_edge_flags) |
1563 | make_edge (src, target, abnormal_edge_flags); | |
1564 | ||
b8698a0f | 1565 | df_mark_solutions_dirty (); |
ca6c03ca JH |
1566 | return new_bb; |
1567 | } | |
1568 | ||
1569 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1570 | (and possibly create new basic block) to make edge non-fallthru. | |
1571 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1572 | |
cf103ca4 EB |
1573 | static basic_block |
1574 | rtl_force_nonfallthru (edge e) | |
ca6c03ca | 1575 | { |
26898771 | 1576 | return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX); |
ca6c03ca JH |
1577 | } |
1578 | ||
1579 | /* Redirect edge even at the expense of creating new jump insn or | |
1580 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1581 | Conversion must be possible. */ |
ca6c03ca | 1582 | |
9ee634e3 | 1583 | static basic_block |
d329e058 | 1584 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1585 | { |
5f0d2358 RK |
1586 | if (redirect_edge_and_branch (e, target) |
1587 | || e->dest == target) | |
ca6c03ca JH |
1588 | return NULL; |
1589 | ||
1590 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1591 | and redirect newly created simplejump. */ | |
6fb5fa3c | 1592 | df_set_bb_dirty (e->src); |
26898771 | 1593 | return force_nonfallthru_and_redirect (e, target, NULL_RTX); |
ca6c03ca JH |
1594 | } |
1595 | ||
1596 | /* The given edge should potentially be a fallthru edge. If that is in | |
1597 | fact true, delete the jump and barriers that are in the way. */ | |
1598 | ||
f470c378 ZD |
1599 | static void |
1600 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1601 | { |
1602 | rtx q; | |
f470c378 ZD |
1603 | basic_block b = e->src, c = b->next_bb; |
1604 | ||
ca6c03ca JH |
1605 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1606 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1607 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1608 | |
1609 | We can also wind up with a sequence of undeletable labels between | |
1610 | one block and the next. | |
1611 | ||
1612 | So search through a sequence of barriers, labels, and notes for | |
1613 | the head of block C and assert that we really do fall through. */ | |
1614 | ||
a813c111 | 1615 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1616 | if (INSN_P (q)) |
1617 | return; | |
ca6c03ca JH |
1618 | |
1619 | /* Remove what will soon cease being the jump insn from the source block. | |
1620 | If block B consisted only of this single jump, turn it into a deleted | |
1621 | note. */ | |
a813c111 | 1622 | q = BB_END (b); |
4b4bf941 | 1623 | if (JUMP_P (q) |
ca6c03ca JH |
1624 | && onlyjump_p (q) |
1625 | && (any_uncondjump_p (q) | |
c5cbcccf | 1626 | || single_succ_p (b))) |
ca6c03ca JH |
1627 | { |
1628 | #ifdef HAVE_cc0 | |
1629 | /* If this was a conditional jump, we need to also delete | |
1630 | the insn that set cc0. */ | |
1631 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1632 | q = PREV_INSN (q); | |
1633 | #endif | |
1634 | ||
1635 | q = PREV_INSN (q); | |
ca6c03ca JH |
1636 | } |
1637 | ||
1638 | /* Selectively unlink the sequence. */ | |
a813c111 | 1639 | if (q != PREV_INSN (BB_HEAD (c))) |
a7b87f73 | 1640 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false); |
ca6c03ca JH |
1641 | |
1642 | e->flags |= EDGE_FALLTHRU; | |
1643 | } | |
ca6c03ca | 1644 | \f |
f470c378 ZD |
1645 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1646 | ||
1647 | static bool | |
1648 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1649 | basic_block after ATTRIBUTE_UNUSED) | |
1650 | { | |
1651 | return false; | |
1652 | } | |
1653 | ||
ca6c03ca | 1654 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1655 | The edge must not be abnormal. |
ca6c03ca JH |
1656 | |
1657 | ??? The code generally expects to be called on critical edges. | |
1658 | The case of a block ending in an unconditional jump to a | |
1659 | block with multiple predecessors is not handled optimally. */ | |
1660 | ||
8ce33230 | 1661 | static basic_block |
d329e058 | 1662 | rtl_split_edge (edge edge_in) |
ca6c03ca JH |
1663 | { |
1664 | basic_block bb; | |
ca6c03ca JH |
1665 | rtx before; |
1666 | ||
1667 | /* Abnormal edges cannot be split. */ | |
341c100f | 1668 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1669 | |
1670 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1671 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1672 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1673 | { | |
0fd4b31d | 1674 | edge e = find_fallthru_edge (edge_in->dest->preds); |
ca6c03ca JH |
1675 | |
1676 | if (e) | |
1677 | force_nonfallthru (e); | |
1678 | } | |
1679 | ||
96e82e0a ZD |
1680 | /* Create the basic block note. */ |
1681 | if (edge_in->dest != EXIT_BLOCK_PTR) | |
a813c111 | 1682 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1683 | else |
1684 | before = NULL_RTX; | |
1685 | ||
623a66fa | 1686 | /* If this is a fall through edge to the exit block, the blocks might be |
ffe14686 AM |
1687 | not adjacent, and the right place is after the source. */ |
1688 | if ((edge_in->flags & EDGE_FALLTHRU) && edge_in->dest == EXIT_BLOCK_PTR) | |
623a66fa R |
1689 | { |
1690 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1691 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1692 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1693 | } |
1694 | else | |
9fb32434 CT |
1695 | { |
1696 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
076c7ab8 ZW |
1697 | /* ??? Why not edge_in->dest->prev_bb here? */ |
1698 | BB_COPY_PARTITION (bb, edge_in->dest); | |
9fb32434 | 1699 | } |
ca6c03ca | 1700 | |
4977bab6 | 1701 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1702 | |
4d6922ee | 1703 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1704 | jump instruction to target our new block. */ |
1705 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1706 | { | |
341c100f NS |
1707 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1708 | gcc_assert (redirected); | |
ca6c03ca JH |
1709 | } |
1710 | else | |
3b5fda81 JJ |
1711 | { |
1712 | if (edge_in->src != ENTRY_BLOCK_PTR) | |
1713 | { | |
1714 | /* For asm goto even splitting of fallthru edge might | |
1715 | need insn patching, as other labels might point to the | |
1716 | old label. */ | |
1717 | rtx last = BB_END (edge_in->src); | |
1718 | if (last | |
1719 | && JUMP_P (last) | |
1720 | && edge_in->dest != EXIT_BLOCK_PTR | |
1721 | && extract_asm_operands (PATTERN (last)) != NULL_RTX | |
1722 | && patch_jump_insn (last, before, bb)) | |
1723 | df_set_bb_dirty (edge_in->src); | |
1724 | } | |
1725 | redirect_edge_succ (edge_in, bb); | |
1726 | } | |
ca6c03ca JH |
1727 | |
1728 | return bb; | |
1729 | } | |
1730 | ||
1731 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1732 | The new instructions and basic blocks (if any) will not appear in the | |
1733 | CFG until commit_edge_insertions is called. */ | |
1734 | ||
1735 | void | |
d329e058 | 1736 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1737 | { |
1738 | /* We cannot insert instructions on an abnormal critical edge. | |
1739 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1740 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1741 | |
6de9cd9a | 1742 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1743 | start_sequence (); |
1744 | else | |
6de9cd9a | 1745 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1746 | |
1747 | emit_insn (pattern); | |
1748 | ||
6de9cd9a | 1749 | e->insns.r = get_insns (); |
ca6c03ca JH |
1750 | end_sequence (); |
1751 | } | |
1752 | ||
1753 | /* Update the CFG for the instructions queued on edge E. */ | |
1754 | ||
4e3825db | 1755 | void |
2ac66157 | 1756 | commit_one_edge_insertion (edge e) |
ca6c03ca JH |
1757 | { |
1758 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
898c90c0 | 1759 | basic_block bb; |
ca6c03ca JH |
1760 | |
1761 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1762 | insns = e->insns.r; |
1763 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1764 | |
898c90c0 EB |
1765 | /* Figure out where to put these insns. If the destination has |
1766 | one predecessor, insert there. Except for the exit block. */ | |
1767 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR) | |
ca6c03ca | 1768 | { |
898c90c0 EB |
1769 | bb = e->dest; |
1770 | ||
1771 | /* Get the location correct wrt a code label, and "nice" wrt | |
1772 | a basic block note, and before everything else. */ | |
1773 | tmp = BB_HEAD (bb); | |
1774 | if (LABEL_P (tmp)) | |
1775 | tmp = NEXT_INSN (tmp); | |
1776 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1777 | tmp = NEXT_INSN (tmp); | |
1778 | if (tmp == BB_HEAD (bb)) | |
1779 | before = tmp; | |
1780 | else if (tmp) | |
1781 | after = PREV_INSN (tmp); | |
1782 | else | |
1783 | after = get_last_insn (); | |
1784 | } | |
3dec4024 | 1785 | |
898c90c0 EB |
1786 | /* If the source has one successor and the edge is not abnormal, |
1787 | insert there. Except for the entry block. */ | |
1788 | else if ((e->flags & EDGE_ABNORMAL) == 0 | |
1789 | && single_succ_p (e->src) | |
1790 | && e->src != ENTRY_BLOCK_PTR) | |
1791 | { | |
1792 | bb = e->src; | |
3dec4024 | 1793 | |
898c90c0 EB |
1794 | /* It is possible to have a non-simple jump here. Consider a target |
1795 | where some forms of unconditional jumps clobber a register. This | |
1796 | happens on the fr30 for example. | |
ca6c03ca | 1797 | |
898c90c0 EB |
1798 | We know this block has a single successor, so we can just emit |
1799 | the queued insns before the jump. */ | |
1800 | if (JUMP_P (BB_END (bb))) | |
1801 | before = BB_END (bb); | |
3dec4024 JH |
1802 | else |
1803 | { | |
898c90c0 EB |
1804 | /* We'd better be fallthru, or we've lost track of what's what. */ |
1805 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
750054a2 | 1806 | |
898c90c0 | 1807 | after = BB_END (bb); |
ca6c03ca JH |
1808 | } |
1809 | } | |
1810 | ||
898c90c0 EB |
1811 | /* Otherwise we must split the edge. */ |
1812 | else | |
1813 | { | |
1814 | bb = split_edge (e); | |
1815 | after = BB_END (bb); | |
ca6c03ca | 1816 | |
898c90c0 | 1817 | if (flag_reorder_blocks_and_partition |
677f3fa8 | 1818 | && targetm_common.have_named_sections |
898c90c0 EB |
1819 | && e->src != ENTRY_BLOCK_PTR |
1820 | && BB_PARTITION (e->src) == BB_COLD_PARTITION | |
1821 | && !(e->flags & EDGE_CROSSING) | |
1822 | && JUMP_P (after) | |
1823 | && !any_condjump_p (after) | |
1824 | && (single_succ_edge (bb)->flags & EDGE_CROSSING)) | |
1825 | add_reg_note (after, REG_CROSSING_JUMP, NULL_RTX); | |
1826 | } | |
1827 | ||
1828 | /* Now that we've found the spot, do the insertion. */ | |
ca6c03ca JH |
1829 | if (before) |
1830 | { | |
6fb5fa3c | 1831 | emit_insn_before_noloc (insns, before, bb); |
ca6c03ca JH |
1832 | last = prev_nonnote_insn (before); |
1833 | } | |
1834 | else | |
6fb5fa3c | 1835 | last = emit_insn_after_noloc (insns, after, bb); |
ca6c03ca JH |
1836 | |
1837 | if (returnjump_p (last)) | |
1838 | { | |
1839 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
1840 | This is not currently a problem because this only happens |
1841 | for the (single) epilogue, which already has a fallthru edge | |
1842 | to EXIT. */ | |
ca6c03ca | 1843 | |
c5cbcccf | 1844 | e = single_succ_edge (bb); |
341c100f | 1845 | gcc_assert (e->dest == EXIT_BLOCK_PTR |
c5cbcccf | 1846 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 1847 | |
5f0d2358 | 1848 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 1849 | emit_barrier_after (last); |
0b17ab2f | 1850 | |
ca6c03ca JH |
1851 | if (before) |
1852 | delete_insn (before); | |
1853 | } | |
341c100f NS |
1854 | else |
1855 | gcc_assert (!JUMP_P (last)); | |
ca6c03ca JH |
1856 | } |
1857 | ||
1858 | /* Update the CFG for all queued instructions. */ | |
1859 | ||
1860 | void | |
d329e058 | 1861 | commit_edge_insertions (void) |
ca6c03ca | 1862 | { |
ca6c03ca JH |
1863 | basic_block bb; |
1864 | ||
1865 | #ifdef ENABLE_CHECKING | |
1866 | verify_flow_info (); | |
1867 | #endif | |
1868 | ||
e0082a72 | 1869 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
ca6c03ca | 1870 | { |
628f6a4e BE |
1871 | edge e; |
1872 | edge_iterator ei; | |
ca6c03ca | 1873 | |
628f6a4e BE |
1874 | FOR_EACH_EDGE (e, ei, bb->succs) |
1875 | if (e->insns.r) | |
cf103ca4 | 1876 | commit_one_edge_insertion (e); |
3dec4024 | 1877 | } |
ca6c03ca JH |
1878 | } |
1879 | \f | |
6fb5fa3c | 1880 | |
f470c378 | 1881 | /* Print out RTL-specific basic block information (live information |
a315c44c SB |
1882 | at start and end with TDF_DETAILS). FLAGS are the TDF_* masks |
1883 | documented in dumpfile.h. */ | |
ca6c03ca | 1884 | |
10e9fecc | 1885 | static void |
a315c44c | 1886 | rtl_dump_bb (FILE *outf, basic_block bb, int indent, int flags) |
ca6c03ca JH |
1887 | { |
1888 | rtx insn; | |
1889 | rtx last; | |
f470c378 | 1890 | char *s_indent; |
ca6c03ca | 1891 | |
ae50c0cb | 1892 | s_indent = (char *) alloca ((size_t) indent + 1); |
400e39e3 | 1893 | memset (s_indent, ' ', (size_t) indent); |
f470c378 | 1894 | s_indent[indent] = '\0'; |
b8698a0f | 1895 | |
a315c44c | 1896 | if (df && (flags & TDF_DETAILS)) |
6fb5fa3c DB |
1897 | { |
1898 | df_dump_top (bb, outf); | |
1899 | putc ('\n', outf); | |
1900 | } | |
ca6c03ca | 1901 | |
68cc3174 EB |
1902 | if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK) |
1903 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; | |
1904 | insn = NEXT_INSN (insn)) | |
a315c44c | 1905 | { |
7b19209f SB |
1906 | if (flags & TDF_DETAILS) |
1907 | df_dump_insn_top (insn, outf); | |
a315c44c SB |
1908 | if (! (flags & TDF_SLIM)) |
1909 | print_rtl_single (outf, insn); | |
1910 | else | |
1911 | dump_insn_slim (outf, insn); | |
7b19209f SB |
1912 | if (flags & TDF_DETAILS) |
1913 | df_dump_insn_bottom (insn, outf); | |
a315c44c SB |
1914 | } |
1915 | ||
1916 | if (df && (flags & TDF_DETAILS)) | |
6fb5fa3c DB |
1917 | { |
1918 | df_dump_bottom (bb, outf); | |
1919 | putc ('\n', outf); | |
1920 | } | |
1921 | ||
ca6c03ca JH |
1922 | } |
1923 | \f | |
c4669594 SB |
1924 | /* Like dump_function_to_file, but for RTL. Print out dataflow information |
1925 | for the start of each basic block. FLAGS are the TDF_* masks documented | |
1926 | in dumpfile.h. */ | |
ca6c03ca JH |
1927 | |
1928 | void | |
a315c44c | 1929 | print_rtl_with_bb (FILE *outf, const_rtx rtx_first, int flags) |
ca6c03ca | 1930 | { |
22ea9ec0 | 1931 | const_rtx tmp_rtx; |
ca6c03ca JH |
1932 | if (rtx_first == 0) |
1933 | fprintf (outf, "(nil)\n"); | |
1934 | else | |
1935 | { | |
ca6c03ca JH |
1936 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
1937 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
1938 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
1939 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
1940 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
e0082a72 ZD |
1941 | basic_block bb; |
1942 | ||
c4669594 SB |
1943 | /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most |
1944 | insns, but the CFG is not maintained so the basic block info | |
1945 | is not reliable. Therefore it's omitted from the dumps. */ | |
1946 | if (! (cfun->curr_properties & PROP_cfg)) | |
1947 | flags &= ~TDF_BLOCKS; | |
1948 | ||
6fb5fa3c DB |
1949 | if (df) |
1950 | df_dump_start (outf); | |
1951 | ||
c4669594 | 1952 | if (flags & TDF_BLOCKS) |
ca6c03ca | 1953 | { |
c4669594 | 1954 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1955 | { |
c4669594 SB |
1956 | rtx x; |
1957 | ||
1958 | start[INSN_UID (BB_HEAD (bb))] = bb; | |
1959 | end[INSN_UID (BB_END (bb))] = bb; | |
1960 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
1961 | { | |
1962 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 1963 | |
c4669594 SB |
1964 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
1965 | state = IN_ONE_BB; | |
1966 | in_bb_p[INSN_UID (x)] = state; | |
ca6c03ca | 1967 | |
c4669594 SB |
1968 | if (x == BB_END (bb)) |
1969 | break; | |
1970 | } | |
ca6c03ca JH |
1971 | } |
1972 | } | |
1973 | ||
1974 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
1975 | { | |
c4669594 SB |
1976 | if (flags & TDF_BLOCKS) |
1977 | { | |
1978 | bb = start[INSN_UID (tmp_rtx)]; | |
1979 | if (bb != NULL) | |
1980 | { | |
1981 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, true, false); | |
1982 | if (df && (flags & TDF_DETAILS)) | |
1983 | df_dump_top (bb, outf); | |
1984 | } | |
ca6c03ca | 1985 | |
c4669594 SB |
1986 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB |
1987 | && !NOTE_P (tmp_rtx) | |
1988 | && !BARRIER_P (tmp_rtx)) | |
1989 | fprintf (outf, ";; Insn is not within a basic block\n"); | |
1990 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
1991 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
1992 | } | |
ca6c03ca | 1993 | |
7b19209f SB |
1994 | if (flags & TDF_DETAILS) |
1995 | df_dump_insn_top (tmp_rtx, outf); | |
a315c44c SB |
1996 | if (! (flags & TDF_SLIM)) |
1997 | print_rtl_single (outf, tmp_rtx); | |
1998 | else | |
1999 | dump_insn_slim (outf, tmp_rtx); | |
7b19209f SB |
2000 | if (flags & TDF_DETAILS) |
2001 | df_dump_insn_bottom (tmp_rtx, outf); | |
ca6c03ca | 2002 | |
c4669594 SB |
2003 | if (flags & TDF_BLOCKS) |
2004 | { | |
2005 | bb = end[INSN_UID (tmp_rtx)]; | |
2006 | if (bb != NULL) | |
2007 | { | |
2008 | dump_bb_info (outf, bb, 0, dump_flags | TDF_COMMENT, false, true); | |
2009 | if (df && (flags & TDF_DETAILS)) | |
2010 | df_dump_bottom (bb, outf); | |
1b03a96d | 2011 | putc ('\n', outf); |
c4669594 SB |
2012 | } |
2013 | } | |
ca6c03ca JH |
2014 | } |
2015 | ||
2016 | free (start); | |
2017 | free (end); | |
2018 | free (in_bb_p); | |
2019 | } | |
ca6c03ca JH |
2020 | } |
2021 | \f | |
532aafad SB |
2022 | /* Update the branch probability of BB if a REG_BR_PROB is present. */ |
2023 | ||
b446e5a2 | 2024 | void |
d329e058 | 2025 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
2026 | { |
2027 | rtx note; | |
4b4bf941 | 2028 | if (!JUMP_P (BB_END (bb))) |
b446e5a2 | 2029 | return; |
a813c111 | 2030 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
b446e5a2 JH |
2031 | if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability) |
2032 | return; | |
2033 | XEXP (note, 0) = GEN_INT (BRANCH_EDGE (bb)->probability); | |
2034 | } | |
96370780 MK |
2035 | |
2036 | /* Get the last insn associated with block BB (that includes barriers and | |
2037 | tablejumps after BB). */ | |
2038 | rtx | |
2039 | get_last_bb_insn (basic_block bb) | |
2040 | { | |
2041 | rtx tmp; | |
2042 | rtx end = BB_END (bb); | |
2043 | ||
2044 | /* Include any jump table following the basic block. */ | |
2045 | if (tablejump_p (end, NULL, &tmp)) | |
2046 | end = tmp; | |
2047 | ||
2048 | /* Include any barriers that may follow the basic block. */ | |
1e211590 | 2049 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2050 | while (tmp && BARRIER_P (tmp)) |
2051 | { | |
2052 | end = tmp; | |
1e211590 | 2053 | tmp = next_nonnote_insn_bb (end); |
96370780 MK |
2054 | } |
2055 | ||
2056 | return end; | |
2057 | } | |
b446e5a2 | 2058 | \f |
10e9fecc JH |
2059 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2060 | cfglayout RTL. | |
ca6c03ca JH |
2061 | |
2062 | Currently it does following checks: | |
2063 | ||
ca6c03ca | 2064 | - overlapping of basic blocks |
9eab6785 | 2065 | - insns with wrong BLOCK_FOR_INSN pointers |
ca6c03ca | 2066 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) |
f63d1bf7 | 2067 | - tails of basic blocks (ensure that boundary is necessary) |
ca6c03ca JH |
2068 | - scans body of the basic block for JUMP_INSN, CODE_LABEL |
2069 | and NOTE_INSN_BASIC_BLOCK | |
750054a2 | 2070 | - verify that no fall_thru edge crosses hot/cold partition boundaries |
9eab6785 | 2071 | - verify that there are no pending RTL branch predictions |
ca6c03ca JH |
2072 | |
2073 | In future it can be extended check a lot of other stuff as well | |
2074 | (reachability of basic blocks, life information, etc. etc.). */ | |
f470c378 | 2075 | |
10e9fecc | 2076 | static int |
d329e058 | 2077 | rtl_verify_flow_info_1 (void) |
ca6c03ca | 2078 | { |
ca6c03ca | 2079 | rtx x; |
10e9fecc | 2080 | int err = 0; |
94eb5ddb | 2081 | basic_block bb; |
ca6c03ca | 2082 | |
9eab6785 | 2083 | /* Check the general integrity of the basic blocks. */ |
e0082a72 | 2084 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2085 | { |
9eab6785 | 2086 | rtx insn; |
5f0d2358 | 2087 | |
5e2d947c JH |
2088 | if (!(bb->flags & BB_RTL)) |
2089 | { | |
2090 | error ("BB_RTL flag not set for block %d", bb->index); | |
2091 | err = 1; | |
2092 | } | |
2093 | ||
9eab6785 | 2094 | FOR_BB_INSNS (bb, insn) |
8ce9fd5d | 2095 | if (BLOCK_FOR_INSN (insn) != bb) |
9eab6785 SB |
2096 | { |
2097 | error ("insn %d basic block pointer is %d, should be %d", | |
2098 | INSN_UID (insn), | |
2099 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
2100 | bb->index); | |
2101 | err = 1; | |
2102 | } | |
a7b87f73 | 2103 | |
bcc708fc | 2104 | for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2105 | if (!BARRIER_P (insn) |
2106 | && BLOCK_FOR_INSN (insn) != NULL) | |
2107 | { | |
2108 | error ("insn %d in header of bb %d has non-NULL basic block", | |
2109 | INSN_UID (insn), bb->index); | |
2110 | err = 1; | |
2111 | } | |
bcc708fc | 2112 | for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn)) |
a7b87f73 ZD |
2113 | if (!BARRIER_P (insn) |
2114 | && BLOCK_FOR_INSN (insn) != NULL) | |
2115 | { | |
2116 | error ("insn %d in footer of bb %d has non-NULL basic block", | |
2117 | INSN_UID (insn), bb->index); | |
2118 | err = 1; | |
2119 | } | |
ca6c03ca JH |
2120 | } |
2121 | ||
2122 | /* Now check the basic blocks (boundaries etc.) */ | |
e0082a72 | 2123 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 2124 | { |
f99ffaa3 EB |
2125 | int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0; |
2126 | int n_eh = 0, n_abnormal = 0; | |
3cf54412 | 2127 | edge e, fallthru = NULL; |
5a1a3e5e | 2128 | rtx note; |
628f6a4e | 2129 | edge_iterator ei; |
ca6c03ca | 2130 | |
2085a21f | 2131 | if (JUMP_P (BB_END (bb)) |
a813c111 | 2132 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 2133 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 2134 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 2135 | { |
e53de54d JH |
2136 | if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability |
2137 | && profile_status != PROFILE_ABSENT) | |
5a1a3e5e | 2138 | { |
0108ae51 | 2139 | error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i", |
5a1a3e5e JH |
2140 | INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability); |
2141 | err = 1; | |
2142 | } | |
2143 | } | |
628f6a4e | 2144 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 2145 | { |
0be7e7a6 RH |
2146 | bool is_crossing; |
2147 | ||
ca6c03ca | 2148 | if (e->flags & EDGE_FALLTHRU) |
0be7e7a6 RH |
2149 | n_fallthru++, fallthru = e; |
2150 | ||
2151 | is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest) | |
2152 | && e->src != ENTRY_BLOCK_PTR | |
2153 | && e->dest != EXIT_BLOCK_PTR); | |
2154 | if (e->flags & EDGE_CROSSING) | |
750054a2 | 2155 | { |
0be7e7a6 RH |
2156 | if (!is_crossing) |
2157 | { | |
2158 | error ("EDGE_CROSSING incorrectly set across same section"); | |
2159 | err = 1; | |
2160 | } | |
2161 | if (e->flags & EDGE_FALLTHRU) | |
2162 | { | |
f99ffaa3 | 2163 | error ("fallthru edge crosses section boundary in bb %i", |
750054a2 CT |
2164 | e->src->index); |
2165 | err = 1; | |
2166 | } | |
0be7e7a6 RH |
2167 | if (e->flags & EDGE_EH) |
2168 | { | |
f99ffaa3 | 2169 | error ("EH edge crosses section boundary in bb %i", |
0be7e7a6 RH |
2170 | e->src->index); |
2171 | err = 1; | |
2172 | } | |
2173 | } | |
2174 | else if (is_crossing) | |
2175 | { | |
2176 | error ("EDGE_CROSSING missing across section boundary"); | |
2177 | err = 1; | |
750054a2 | 2178 | } |
3dec4024 | 2179 | |
65f43cdf ZD |
2180 | if ((e->flags & ~(EDGE_DFS_BACK |
2181 | | EDGE_CAN_FALLTHRU | |
2182 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 | 2183 | | EDGE_LOOP_EXIT |
7e872b90 JJ |
2184 | | EDGE_CROSSING |
2185 | | EDGE_PRESERVE)) == 0) | |
3dec4024 JH |
2186 | n_branch++; |
2187 | ||
2188 | if (e->flags & EDGE_ABNORMAL_CALL) | |
f99ffaa3 EB |
2189 | n_abnormal_call++; |
2190 | ||
2191 | if (e->flags & EDGE_SIBCALL) | |
2192 | n_sibcall++; | |
3dec4024 JH |
2193 | |
2194 | if (e->flags & EDGE_EH) | |
2195 | n_eh++; | |
f99ffaa3 EB |
2196 | |
2197 | if (e->flags & EDGE_ABNORMAL) | |
3dec4024 | 2198 | n_abnormal++; |
ca6c03ca | 2199 | } |
5f0d2358 | 2200 | |
1d65f45c | 2201 | if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) |
3dec4024 | 2202 | { |
f99ffaa3 | 2203 | error ("missing REG_EH_REGION note at the end of bb %i", bb->index); |
3dec4024 JH |
2204 | err = 1; |
2205 | } | |
1d65f45c RH |
2206 | if (n_eh > 1) |
2207 | { | |
f99ffaa3 | 2208 | error ("too many exception handling edges in bb %i", bb->index); |
1d65f45c RH |
2209 | err = 1; |
2210 | } | |
3dec4024 | 2211 | if (n_branch |
4b4bf941 | 2212 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2213 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
2214 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 2215 | { |
ab532386 | 2216 | error ("too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
2217 | err = 1; |
2218 | } | |
a813c111 | 2219 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2220 | { |
f99ffaa3 | 2221 | error ("fallthru edge after unconditional jump in bb %i", bb->index); |
3dec4024 JH |
2222 | err = 1; |
2223 | } | |
a813c111 | 2224 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 2225 | { |
f99ffaa3 EB |
2226 | error ("wrong number of branch edges after unconditional jump" |
2227 | " in bb %i", bb->index); | |
3dec4024 JH |
2228 | err = 1; |
2229 | } | |
a813c111 | 2230 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 2231 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 2232 | { |
f99ffaa3 EB |
2233 | error ("wrong amount of branch edges after conditional jump" |
2234 | " in bb %i", bb->index); | |
2235 | err = 1; | |
2236 | } | |
2237 | if (n_abnormal_call && !CALL_P (BB_END (bb))) | |
2238 | { | |
2239 | error ("abnormal call edges for non-call insn in bb %i", bb->index); | |
3dec4024 JH |
2240 | err = 1; |
2241 | } | |
f99ffaa3 | 2242 | if (n_sibcall && !CALL_P (BB_END (bb))) |
3dec4024 | 2243 | { |
f99ffaa3 | 2244 | error ("sibcall edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
2245 | err = 1; |
2246 | } | |
f99ffaa3 EB |
2247 | if (n_abnormal > n_eh |
2248 | && !(CALL_P (BB_END (bb)) | |
2249 | && n_abnormal == n_abnormal_call + n_sibcall) | |
4b4bf941 | 2250 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
2251 | || any_condjump_p (BB_END (bb)) |
2252 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 2253 | { |
ab532386 | 2254 | error ("abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
2255 | err = 1; |
2256 | } | |
f87c27b4 | 2257 | |
a813c111 | 2258 | for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x)) |
0ca541aa | 2259 | /* We may have a barrier inside a basic block before dead code |
9524880c HPN |
2260 | elimination. There is no BLOCK_FOR_INSN field in a barrier. */ |
2261 | if (!BARRIER_P (x) && BLOCK_FOR_INSN (x) != bb) | |
5f0d2358 RK |
2262 | { |
2263 | debug_rtx (x); | |
2264 | if (! BLOCK_FOR_INSN (x)) | |
2265 | error | |
2266 | ("insn %d inside basic block %d but block_for_insn is NULL", | |
0b17ab2f | 2267 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2268 | else |
2269 | error | |
2270 | ("insn %d inside basic block %d but block_for_insn is %i", | |
0b17ab2f | 2271 | INSN_UID (x), bb->index, BLOCK_FOR_INSN (x)->index); |
5f0d2358 RK |
2272 | |
2273 | err = 1; | |
2274 | } | |
ca6c03ca JH |
2275 | |
2276 | /* OK pointers are correct. Now check the header of basic | |
c22cacf3 | 2277 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 2278 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 2279 | x = BB_HEAD (bb); |
4b4bf941 | 2280 | if (LABEL_P (x)) |
ca6c03ca | 2281 | { |
a813c111 | 2282 | if (BB_END (bb) == x) |
ca6c03ca JH |
2283 | { |
2284 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2285 | bb->index); |
ca6c03ca JH |
2286 | err = 1; |
2287 | } | |
5f0d2358 | 2288 | |
ca6c03ca JH |
2289 | x = NEXT_INSN (x); |
2290 | } | |
5f0d2358 | 2291 | |
ca6c03ca JH |
2292 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
2293 | { | |
2294 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 2295 | bb->index); |
ca6c03ca JH |
2296 | err = 1; |
2297 | } | |
2298 | ||
a813c111 | 2299 | if (BB_END (bb) == x) |
49243025 | 2300 | /* Do checks for empty blocks here. */ |
5f0d2358 | 2301 | ; |
ca6c03ca | 2302 | else |
5f0d2358 RK |
2303 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
2304 | { | |
2305 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2306 | { | |
2307 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 2308 | INSN_UID (x), bb->index); |
5f0d2358 RK |
2309 | err = 1; |
2310 | } | |
2311 | ||
a813c111 | 2312 | if (x == BB_END (bb)) |
5f0d2358 | 2313 | break; |
ca6c03ca | 2314 | |
83fd323c | 2315 | if (control_flow_insn_p (x)) |
5f0d2358 | 2316 | { |
0b17ab2f | 2317 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
2318 | fatal_insn ("flow control insn inside a basic block", x); |
2319 | } | |
2320 | } | |
ca6c03ca JH |
2321 | } |
2322 | ||
10e9fecc | 2323 | /* Clean up. */ |
10e9fecc JH |
2324 | return err; |
2325 | } | |
5f0d2358 | 2326 | |
10e9fecc JH |
2327 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
2328 | cfglayout RTL. | |
5f0d2358 | 2329 | |
10e9fecc JH |
2330 | Currently it does following checks: |
2331 | - all checks of rtl_verify_flow_info_1 | |
9eab6785 | 2332 | - test head/end pointers |
10e9fecc JH |
2333 | - check that all insns are in the basic blocks |
2334 | (except the switch handling code, barriers and notes) | |
2335 | - check that all returns are followed by barriers | |
2336 | - check that all fallthru edge points to the adjacent blocks. */ | |
9eab6785 | 2337 | |
10e9fecc | 2338 | static int |
d329e058 | 2339 | rtl_verify_flow_info (void) |
10e9fecc JH |
2340 | { |
2341 | basic_block bb; | |
2342 | int err = rtl_verify_flow_info_1 (); | |
2343 | rtx x; | |
9eab6785 SB |
2344 | rtx last_head = get_last_insn (); |
2345 | basic_block *bb_info; | |
10e9fecc JH |
2346 | int num_bb_notes; |
2347 | const rtx rtx_first = get_insns (); | |
2348 | basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL; | |
9eab6785 SB |
2349 | const int max_uid = get_max_uid (); |
2350 | ||
2351 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 2352 | |
10e9fecc JH |
2353 | FOR_EACH_BB_REVERSE (bb) |
2354 | { | |
2355 | edge e; | |
9eab6785 SB |
2356 | rtx head = BB_HEAD (bb); |
2357 | rtx end = BB_END (bb); | |
628f6a4e | 2358 | |
9eab6785 | 2359 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
a7b87f73 ZD |
2360 | { |
2361 | /* Verify the end of the basic block is in the INSN chain. */ | |
2362 | if (x == end) | |
2363 | break; | |
2364 | ||
2365 | /* And that the code outside of basic blocks has NULL bb field. */ | |
2366 | if (!BARRIER_P (x) | |
2367 | && BLOCK_FOR_INSN (x) != NULL) | |
2368 | { | |
2369 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2370 | INSN_UID (x)); | |
2371 | err = 1; | |
2372 | } | |
2373 | } | |
9eab6785 SB |
2374 | |
2375 | if (!x) | |
2376 | { | |
2377 | error ("end insn %d for block %d not found in the insn stream", | |
2378 | INSN_UID (end), bb->index); | |
2379 | err = 1; | |
2380 | } | |
2381 | ||
2382 | /* Work backwards from the end to the head of the basic block | |
2383 | to verify the head is in the RTL chain. */ | |
2384 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 2385 | { |
9eab6785 SB |
2386 | /* While walking over the insn chain, verify insns appear |
2387 | in only one basic block. */ | |
2388 | if (bb_info[INSN_UID (x)] != NULL) | |
2389 | { | |
2390 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
2391 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
2392 | err = 1; | |
2393 | } | |
2394 | ||
2395 | bb_info[INSN_UID (x)] = bb; | |
2396 | ||
2397 | if (x == head) | |
2398 | break; | |
2399 | } | |
2400 | if (!x) | |
2401 | { | |
2402 | error ("head insn %d for block %d not found in the insn stream", | |
2403 | INSN_UID (head), bb->index); | |
a00d11f0 JH |
2404 | err = 1; |
2405 | } | |
2406 | ||
a7b87f73 | 2407 | last_head = PREV_INSN (x); |
9eab6785 | 2408 | |
0fd4b31d | 2409 | e = find_fallthru_edge (bb->succs); |
10e9fecc JH |
2410 | if (!e) |
2411 | { | |
2412 | rtx insn; | |
2413 | ||
2414 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
468059bc DD |
2415 | for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn)) |
2416 | { | |
2417 | if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
10e9fecc JH |
2418 | { |
2419 | error ("missing barrier after block %i", bb->index); | |
2420 | err = 1; | |
2421 | break; | |
2422 | } | |
468059bc DD |
2423 | if (BARRIER_P (insn)) |
2424 | break; | |
2425 | } | |
10e9fecc JH |
2426 | } |
2427 | else if (e->src != ENTRY_BLOCK_PTR | |
2428 | && e->dest != EXIT_BLOCK_PTR) | |
c22cacf3 | 2429 | { |
10e9fecc JH |
2430 | rtx insn; |
2431 | ||
2432 | if (e->src->next_bb != e->dest) | |
2433 | { | |
2434 | error | |
2435 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
2436 | e->src->index, e->dest->index); | |
2437 | err = 1; | |
2438 | } | |
2439 | else | |
a813c111 | 2440 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 2441 | insn = NEXT_INSN (insn)) |
6be85b25 | 2442 | if (BARRIER_P (insn) || INSN_P (insn)) |
10e9fecc JH |
2443 | { |
2444 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2445 | e->src->index, e->dest->index); | |
2446 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2447 | err = 1; | |
2448 | } | |
c22cacf3 | 2449 | } |
10e9fecc | 2450 | } |
ca6c03ca | 2451 | |
a7b87f73 ZD |
2452 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) |
2453 | { | |
2454 | /* Check that the code before the first basic block has NULL | |
2455 | bb field. */ | |
2456 | if (!BARRIER_P (x) | |
2457 | && BLOCK_FOR_INSN (x) != NULL) | |
2458 | { | |
2459 | error ("insn %d outside of basic blocks has non-NULL bb field", | |
2460 | INSN_UID (x)); | |
2461 | err = 1; | |
2462 | } | |
2463 | } | |
9eab6785 SB |
2464 | free (bb_info); |
2465 | ||
ca6c03ca | 2466 | num_bb_notes = 0; |
e0082a72 ZD |
2467 | last_bb_seen = ENTRY_BLOCK_PTR; |
2468 | ||
5f0d2358 | 2469 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2470 | { |
2471 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2472 | { | |
bf77398c | 2473 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2474 | |
ca6c03ca | 2475 | num_bb_notes++; |
e0082a72 | 2476 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2477 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2478 | |
10e9fecc | 2479 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2480 | } |
2481 | ||
10e9fecc | 2482 | if (!curr_bb) |
ca6c03ca JH |
2483 | { |
2484 | switch (GET_CODE (x)) | |
2485 | { | |
2486 | case BARRIER: | |
2487 | case NOTE: | |
2488 | break; | |
2489 | ||
2490 | case CODE_LABEL: | |
666c27b9 | 2491 | /* An addr_vec is placed outside any basic block. */ |
ca6c03ca | 2492 | if (NEXT_INSN (x) |
481683e1 | 2493 | && JUMP_TABLE_DATA_P (NEXT_INSN (x))) |
5f0d2358 | 2494 | x = NEXT_INSN (x); |
ca6c03ca JH |
2495 | |
2496 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2497 | break; | |
2498 | ||
2499 | default: | |
1f978f5f | 2500 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2501 | } |
2502 | } | |
2503 | ||
26cae194 | 2504 | if (JUMP_P (x) |
ca6c03ca | 2505 | && returnjump_p (x) && ! condjump_p (x) |
15eb3a2e | 2506 | && ! (next_nonnote_insn (x) && BARRIER_P (next_nonnote_insn (x)))) |
1f978f5f | 2507 | fatal_insn ("return not followed by barrier", x); |
a813c111 | 2508 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2509 | curr_bb = NULL; |
ca6c03ca JH |
2510 | } |
2511 | ||
24bd1a0b | 2512 | if (num_bb_notes != n_basic_blocks - NUM_FIXED_BLOCKS) |
ca6c03ca | 2513 | internal_error |
0b17ab2f RH |
2514 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
2515 | num_bb_notes, n_basic_blocks); | |
ca6c03ca | 2516 | |
10e9fecc | 2517 | return err; |
ca6c03ca JH |
2518 | } |
2519 | \f | |
eaec9b3d | 2520 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2521 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2522 | Return true if any edges are eliminated. */ | |
2523 | ||
2524 | bool | |
d329e058 | 2525 | purge_dead_edges (basic_block bb) |
ca6c03ca | 2526 | { |
628f6a4e | 2527 | edge e; |
a813c111 | 2528 | rtx insn = BB_END (bb), note; |
ca6c03ca | 2529 | bool purged = false; |
628f6a4e BE |
2530 | bool found; |
2531 | edge_iterator ei; | |
ca6c03ca | 2532 | |
b5b8b0ac AO |
2533 | if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) |
2534 | do | |
2535 | insn = PREV_INSN (insn); | |
2536 | while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); | |
2537 | ||
70da1d03 | 2538 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 2539 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
2540 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2541 | { | |
2542 | rtx eqnote; | |
2543 | ||
2544 | if (! may_trap_p (PATTERN (insn)) | |
2545 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2546 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
2547 | remove_note (insn, note); | |
2548 | } | |
2549 | ||
546c093e | 2550 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 2551 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 2552 | { |
1d65f45c RH |
2553 | bool remove = false; |
2554 | ||
e5f9a909 JW |
2555 | /* There are three types of edges we need to handle correctly here: EH |
2556 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
2557 | latter can appear when nonlocal gotos are used. */ | |
1d65f45c | 2558 | if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 2559 | { |
1d65f45c RH |
2560 | if (!CALL_P (insn)) |
2561 | remove = true; | |
2562 | else if (can_nonlocal_goto (insn)) | |
2563 | ; | |
2564 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) | |
2565 | ; | |
0a35513e AH |
2566 | else if (flag_tm && find_reg_note (insn, REG_TM, NULL)) |
2567 | ; | |
1d65f45c RH |
2568 | else |
2569 | remove = true; | |
546c093e | 2570 | } |
1d65f45c RH |
2571 | else if (e->flags & EDGE_EH) |
2572 | remove = !can_throw_internal (insn); | |
2573 | ||
2574 | if (remove) | |
546c093e | 2575 | { |
1d65f45c RH |
2576 | remove_edge (e); |
2577 | df_set_bb_dirty (bb); | |
2578 | purged = true; | |
546c093e RH |
2579 | } |
2580 | else | |
1d65f45c | 2581 | ei_next (&ei); |
546c093e | 2582 | } |
5f0d2358 | 2583 | |
4b4bf941 | 2584 | if (JUMP_P (insn)) |
ca6c03ca JH |
2585 | { |
2586 | rtx note; | |
2587 | edge b,f; | |
628f6a4e | 2588 | edge_iterator ei; |
5f0d2358 | 2589 | |
ca6c03ca JH |
2590 | /* We do care only about conditional jumps and simplejumps. */ |
2591 | if (!any_condjump_p (insn) | |
2592 | && !returnjump_p (insn) | |
2593 | && !simplejump_p (insn)) | |
c51d95ec | 2594 | return purged; |
5f0d2358 | 2595 | |
5a1a3e5e JH |
2596 | /* Branch probability/prediction notes are defined only for |
2597 | condjumps. We've possibly turned condjump into simplejump. */ | |
2598 | if (simplejump_p (insn)) | |
2599 | { | |
2600 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2601 | if (note) | |
2602 | remove_note (insn, note); | |
2603 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
2604 | remove_note (insn, note); | |
2605 | } | |
2606 | ||
628f6a4e | 2607 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2608 | { |
7fcd7218 JH |
2609 | /* Avoid abnormal flags to leak from computed jumps turned |
2610 | into simplejumps. */ | |
f87c27b4 | 2611 | |
0e1638d4 | 2612 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 2613 | |
5a566bed MM |
2614 | /* See if this edge is one we should keep. */ |
2615 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
2616 | /* A conditional jump can fall through into the next | |
2617 | block, so we should keep the edge. */ | |
628f6a4e BE |
2618 | { |
2619 | ei_next (&ei); | |
2620 | continue; | |
2621 | } | |
5f0d2358 | 2622 | else if (e->dest != EXIT_BLOCK_PTR |
a813c111 | 2623 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
2624 | /* If the destination block is the target of the jump, |
2625 | keep the edge. */ | |
628f6a4e BE |
2626 | { |
2627 | ei_next (&ei); | |
2628 | continue; | |
2629 | } | |
5a566bed MM |
2630 | else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn)) |
2631 | /* If the destination block is the exit block, and this | |
2632 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
2633 | { |
2634 | ei_next (&ei); | |
2635 | continue; | |
2636 | } | |
5a566bed MM |
2637 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
2638 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
2639 | this instruction and rematerialize the EDGE_ABNORMAL |
2640 | flag we just cleared above. */ | |
2641 | { | |
2642 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 2643 | ei_next (&ei); |
0b75beaa EB |
2644 | continue; |
2645 | } | |
5f0d2358 | 2646 | |
5a566bed | 2647 | /* We do not need this edge. */ |
6fb5fa3c | 2648 | df_set_bb_dirty (bb); |
ca6c03ca JH |
2649 | purged = true; |
2650 | remove_edge (e); | |
2651 | } | |
5f0d2358 | 2652 | |
628f6a4e | 2653 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 2654 | return purged; |
5f0d2358 | 2655 | |
c263766c RH |
2656 | if (dump_file) |
2657 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 2658 | |
ca6c03ca JH |
2659 | if (!optimize) |
2660 | return purged; | |
2661 | ||
2662 | /* Redistribute probabilities. */ | |
c5cbcccf | 2663 | if (single_succ_p (bb)) |
ca6c03ca | 2664 | { |
c5cbcccf ZD |
2665 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2666 | single_succ_edge (bb)->count = bb->count; | |
f87c27b4 | 2667 | } |
ca6c03ca JH |
2668 | else |
2669 | { | |
2670 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2671 | if (!note) | |
2672 | return purged; | |
5f0d2358 | 2673 | |
ca6c03ca JH |
2674 | b = BRANCH_EDGE (bb); |
2675 | f = FALLTHRU_EDGE (bb); | |
2676 | b->probability = INTVAL (XEXP (note, 0)); | |
2677 | f->probability = REG_BR_PROB_BASE - b->probability; | |
2678 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; | |
2679 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
2680 | } | |
5f0d2358 | 2681 | |
ca6c03ca JH |
2682 | return purged; |
2683 | } | |
4b4bf941 | 2684 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
2685 | { |
2686 | /* First, there should not be any EH or ABCALL edges resulting | |
2687 | from non-local gotos and the like. If there were, we shouldn't | |
2688 | have created the sibcall in the first place. Second, there | |
2689 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
2690 | gcc_assert (single_succ_p (bb)); |
2691 | gcc_assert (single_succ_edge (bb)->flags | |
2692 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 RH |
2693 | |
2694 | return 0; | |
2695 | } | |
ca6c03ca | 2696 | |
ca6c03ca JH |
2697 | /* If we don't see a jump insn, we don't know exactly why the block would |
2698 | have been broken at this point. Look for a simple, non-fallthru edge, | |
2699 | as these are only created by conditional branches. If we find such an | |
2700 | edge we know that there used to be a jump here and can then safely | |
2701 | remove all non-fallthru edges. */ | |
628f6a4e BE |
2702 | found = false; |
2703 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2704 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
2705 | { | |
2706 | found = true; | |
2707 | break; | |
2708 | } | |
5f0d2358 | 2709 | |
628f6a4e | 2710 | if (!found) |
ca6c03ca | 2711 | return purged; |
5f0d2358 | 2712 | |
2afa8dce DB |
2713 | /* Remove all but the fake and fallthru edges. The fake edge may be |
2714 | the only successor for this block in the case of noreturn | |
2715 | calls. */ | |
628f6a4e | 2716 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2717 | { |
2afa8dce | 2718 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec | 2719 | { |
6fb5fa3c | 2720 | df_set_bb_dirty (bb); |
c51d95ec JH |
2721 | remove_edge (e); |
2722 | purged = true; | |
2723 | } | |
628f6a4e BE |
2724 | else |
2725 | ei_next (&ei); | |
ca6c03ca | 2726 | } |
5f0d2358 | 2727 | |
c5cbcccf | 2728 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 2729 | |
c5cbcccf ZD |
2730 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2731 | single_succ_edge (bb)->count = bb->count; | |
ca6c03ca | 2732 | |
c263766c RH |
2733 | if (dump_file) |
2734 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 2735 | bb->index); |
ca6c03ca JH |
2736 | return purged; |
2737 | } | |
2738 | ||
5f0d2358 RK |
2739 | /* Search all basic blocks for potentially dead edges and purge them. Return |
2740 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
2741 | |
2742 | bool | |
25cd19de | 2743 | purge_all_dead_edges (void) |
ca6c03ca | 2744 | { |
e0082a72 | 2745 | int purged = false; |
e0082a72 | 2746 | basic_block bb; |
473fb060 | 2747 | |
e0082a72 | 2748 | FOR_EACH_BB (bb) |
473fb060 | 2749 | { |
e0082a72 | 2750 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 2751 | |
473fb060 | 2752 | purged |= purged_here; |
473fb060 | 2753 | } |
5f0d2358 | 2754 | |
ca6c03ca JH |
2755 | return purged; |
2756 | } | |
9ee634e3 | 2757 | |
ba5e9aca EB |
2758 | /* This is used by a few passes that emit some instructions after abnormal |
2759 | calls, moving the basic block's end, while they in fact do want to emit | |
2760 | them on the fallthru edge. Look for abnormal call edges, find backward | |
2761 | the call in the block and insert the instructions on the edge instead. | |
2762 | ||
2763 | Similarly, handle instructions throwing exceptions internally. | |
2764 | ||
2765 | Return true when instructions have been found and inserted on edges. */ | |
2766 | ||
2767 | bool | |
2768 | fixup_abnormal_edges (void) | |
2769 | { | |
2770 | bool inserted = false; | |
2771 | basic_block bb; | |
2772 | ||
2773 | FOR_EACH_BB (bb) | |
2774 | { | |
2775 | edge e; | |
2776 | edge_iterator ei; | |
2777 | ||
2778 | /* Look for cases we are interested in - calls or instructions causing | |
2779 | exceptions. */ | |
2780 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2781 | if ((e->flags & EDGE_ABNORMAL_CALL) | |
2782 | || ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) | |
2783 | == (EDGE_ABNORMAL | EDGE_EH))) | |
2784 | break; | |
2785 | ||
2786 | if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb))) | |
2787 | { | |
2788 | rtx insn; | |
2789 | ||
2790 | /* Get past the new insns generated. Allow notes, as the insns | |
2791 | may be already deleted. */ | |
2792 | insn = BB_END (bb); | |
2793 | while ((NONJUMP_INSN_P (insn) || NOTE_P (insn)) | |
2794 | && !can_throw_internal (insn) | |
2795 | && insn != BB_HEAD (bb)) | |
2796 | insn = PREV_INSN (insn); | |
2797 | ||
2798 | if (CALL_P (insn) || can_throw_internal (insn)) | |
2799 | { | |
2800 | rtx stop, next; | |
2801 | ||
2802 | e = find_fallthru_edge (bb->succs); | |
2803 | ||
2804 | stop = NEXT_INSN (BB_END (bb)); | |
2805 | BB_END (bb) = insn; | |
2806 | ||
2807 | for (insn = NEXT_INSN (insn); insn != stop; insn = next) | |
2808 | { | |
2809 | next = NEXT_INSN (insn); | |
2810 | if (INSN_P (insn)) | |
2811 | { | |
2812 | delete_insn (insn); | |
2813 | ||
2814 | /* Sometimes there's still the return value USE. | |
2815 | If it's placed after a trapping call (i.e. that | |
2816 | call is the last insn anyway), we have no fallthru | |
2817 | edge. Simply delete this use and don't try to insert | |
2818 | on the non-existent edge. */ | |
2819 | if (GET_CODE (PATTERN (insn)) != USE) | |
2820 | { | |
2821 | /* We're not deleting it, we're moving it. */ | |
2822 | INSN_DELETED_P (insn) = 0; | |
2823 | PREV_INSN (insn) = NULL_RTX; | |
2824 | NEXT_INSN (insn) = NULL_RTX; | |
2825 | ||
2826 | insert_insn_on_edge (insn, e); | |
2827 | inserted = true; | |
2828 | } | |
2829 | } | |
2830 | else if (!BARRIER_P (insn)) | |
2831 | set_block_for_insn (insn, NULL); | |
2832 | } | |
2833 | } | |
2834 | ||
2835 | /* It may be that we don't find any trapping insn. In this | |
2836 | case we discovered quite late that the insn that had been | |
2837 | marked as can_throw_internal in fact couldn't trap at all. | |
2838 | So we should in fact delete the EH edges out of the block. */ | |
2839 | else | |
2840 | purge_dead_edges (bb); | |
2841 | } | |
2842 | } | |
2843 | ||
2844 | return inserted; | |
2845 | } | |
78bde837 SB |
2846 | \f |
2847 | /* Cut the insns from FIRST to LAST out of the insns stream. */ | |
2848 | ||
2849 | rtx | |
2850 | unlink_insn_chain (rtx first, rtx last) | |
2851 | { | |
2852 | rtx prevfirst = PREV_INSN (first); | |
2853 | rtx nextlast = NEXT_INSN (last); | |
2854 | ||
2855 | PREV_INSN (first) = NULL; | |
2856 | NEXT_INSN (last) = NULL; | |
2857 | if (prevfirst) | |
2858 | NEXT_INSN (prevfirst) = nextlast; | |
2859 | if (nextlast) | |
2860 | PREV_INSN (nextlast) = prevfirst; | |
2861 | else | |
2862 | set_last_insn (prevfirst); | |
2863 | if (!prevfirst) | |
2864 | set_first_insn (nextlast); | |
2865 | return first; | |
2866 | } | |
2867 | \f | |
2868 | /* Skip over inter-block insns occurring after BB which are typically | |
2869 | associated with BB (e.g., barriers). If there are any such insns, | |
2870 | we return the last one. Otherwise, we return the end of BB. */ | |
2871 | ||
2872 | static rtx | |
2873 | skip_insns_after_block (basic_block bb) | |
2874 | { | |
2875 | rtx insn, last_insn, next_head, prev; | |
2876 | ||
2877 | next_head = NULL_RTX; | |
2878 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
2879 | next_head = BB_HEAD (bb->next_bb); | |
2880 | ||
2881 | for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; ) | |
2882 | { | |
2883 | if (insn == next_head) | |
2884 | break; | |
2885 | ||
2886 | switch (GET_CODE (insn)) | |
2887 | { | |
2888 | case BARRIER: | |
2889 | last_insn = insn; | |
2890 | continue; | |
2891 | ||
2892 | case NOTE: | |
2893 | switch (NOTE_KIND (insn)) | |
2894 | { | |
2895 | case NOTE_INSN_BLOCK_END: | |
2896 | gcc_unreachable (); | |
2897 | continue; | |
2898 | default: | |
2899 | continue; | |
2900 | break; | |
2901 | } | |
2902 | break; | |
2903 | ||
2904 | case CODE_LABEL: | |
2905 | if (NEXT_INSN (insn) | |
2906 | && JUMP_TABLE_DATA_P (NEXT_INSN (insn))) | |
2907 | { | |
2908 | insn = NEXT_INSN (insn); | |
2909 | last_insn = insn; | |
2910 | continue; | |
2911 | } | |
2912 | break; | |
2913 | ||
2914 | default: | |
2915 | break; | |
2916 | } | |
2917 | ||
2918 | break; | |
2919 | } | |
2920 | ||
2921 | /* It is possible to hit contradictory sequence. For instance: | |
2922 | ||
2923 | jump_insn | |
2924 | NOTE_INSN_BLOCK_BEG | |
2925 | barrier | |
2926 | ||
2927 | Where barrier belongs to jump_insn, but the note does not. This can be | |
2928 | created by removing the basic block originally following | |
2929 | NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */ | |
2930 | ||
2931 | for (insn = last_insn; insn != BB_END (bb); insn = prev) | |
2932 | { | |
2933 | prev = PREV_INSN (insn); | |
2934 | if (NOTE_P (insn)) | |
2935 | switch (NOTE_KIND (insn)) | |
2936 | { | |
2937 | case NOTE_INSN_BLOCK_END: | |
2938 | gcc_unreachable (); | |
2939 | break; | |
2940 | case NOTE_INSN_DELETED: | |
2941 | case NOTE_INSN_DELETED_LABEL: | |
2942 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
2943 | continue; | |
2944 | default: | |
2945 | reorder_insns (insn, insn, last_insn); | |
2946 | } | |
2947 | } | |
2948 | ||
2949 | return last_insn; | |
2950 | } | |
2951 | ||
2952 | /* Locate or create a label for a given basic block. */ | |
2953 | ||
2954 | static rtx | |
2955 | label_for_bb (basic_block bb) | |
2956 | { | |
2957 | rtx label = BB_HEAD (bb); | |
2958 | ||
2959 | if (!LABEL_P (label)) | |
2960 | { | |
2961 | if (dump_file) | |
2962 | fprintf (dump_file, "Emitting label for block %d\n", bb->index); | |
2963 | ||
2964 | label = block_label (bb); | |
2965 | } | |
2966 | ||
2967 | return label; | |
2968 | } | |
2969 | ||
2970 | /* Locate the effective beginning and end of the insn chain for each | |
2971 | block, as defined by skip_insns_after_block above. */ | |
2972 | ||
2973 | static void | |
2974 | record_effective_endpoints (void) | |
2975 | { | |
2976 | rtx next_insn; | |
2977 | basic_block bb; | |
2978 | rtx insn; | |
2979 | ||
2980 | for (insn = get_insns (); | |
2981 | insn | |
2982 | && NOTE_P (insn) | |
2983 | && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK; | |
2984 | insn = NEXT_INSN (insn)) | |
2985 | continue; | |
2986 | /* No basic blocks at all? */ | |
2987 | gcc_assert (insn); | |
2988 | ||
2989 | if (PREV_INSN (insn)) | |
2990 | cfg_layout_function_header = | |
2991 | unlink_insn_chain (get_insns (), PREV_INSN (insn)); | |
2992 | else | |
2993 | cfg_layout_function_header = NULL_RTX; | |
2994 | ||
2995 | next_insn = get_insns (); | |
2996 | FOR_EACH_BB (bb) | |
2997 | { | |
2998 | rtx end; | |
2999 | ||
3000 | if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb)) | |
3001 | BB_HEADER (bb) = unlink_insn_chain (next_insn, | |
3002 | PREV_INSN (BB_HEAD (bb))); | |
3003 | end = skip_insns_after_block (bb); | |
3004 | if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end) | |
3005 | BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end); | |
3006 | next_insn = NEXT_INSN (BB_END (bb)); | |
3007 | } | |
3008 | ||
3009 | cfg_layout_function_footer = next_insn; | |
3010 | if (cfg_layout_function_footer) | |
3011 | cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ()); | |
3012 | } | |
3013 | \f | |
3014 | static unsigned int | |
3015 | into_cfg_layout_mode (void) | |
3016 | { | |
3017 | cfg_layout_initialize (0); | |
3018 | return 0; | |
3019 | } | |
3020 | ||
3021 | static unsigned int | |
3022 | outof_cfg_layout_mode (void) | |
3023 | { | |
3024 | basic_block bb; | |
3025 | ||
3026 | FOR_EACH_BB (bb) | |
3027 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
3028 | bb->aux = bb->next_bb; | |
3029 | ||
3030 | cfg_layout_finalize (); | |
3031 | ||
3032 | return 0; | |
3033 | } | |
3034 | ||
3035 | struct rtl_opt_pass pass_into_cfg_layout_mode = | |
3036 | { | |
3037 | { | |
3038 | RTL_PASS, | |
3039 | "into_cfglayout", /* name */ | |
2b4e6bf1 | 3040 | OPTGROUP_NONE, /* optinfo_flags */ |
78bde837 SB |
3041 | NULL, /* gate */ |
3042 | into_cfg_layout_mode, /* execute */ | |
3043 | NULL, /* sub */ | |
3044 | NULL, /* next */ | |
3045 | 0, /* static_pass_number */ | |
3046 | TV_CFG, /* tv_id */ | |
3047 | 0, /* properties_required */ | |
3048 | PROP_cfglayout, /* properties_provided */ | |
3049 | 0, /* properties_destroyed */ | |
3050 | 0, /* todo_flags_start */ | |
3051 | 0 /* todo_flags_finish */ | |
3052 | } | |
3053 | }; | |
3054 | ||
3055 | struct rtl_opt_pass pass_outof_cfg_layout_mode = | |
3056 | { | |
3057 | { | |
3058 | RTL_PASS, | |
3059 | "outof_cfglayout", /* name */ | |
2b4e6bf1 | 3060 | OPTGROUP_NONE, /* optinfo_flags */ |
78bde837 SB |
3061 | NULL, /* gate */ |
3062 | outof_cfg_layout_mode, /* execute */ | |
3063 | NULL, /* sub */ | |
3064 | NULL, /* next */ | |
3065 | 0, /* static_pass_number */ | |
3066 | TV_CFG, /* tv_id */ | |
3067 | 0, /* properties_required */ | |
3068 | 0, /* properties_provided */ | |
3069 | PROP_cfglayout, /* properties_destroyed */ | |
3070 | 0, /* todo_flags_start */ | |
3071 | 0 /* todo_flags_finish */ | |
3072 | } | |
3073 | }; | |
3074 | \f | |
3075 | ||
3076 | /* Link the basic blocks in the correct order, compacting the basic | |
3077 | block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this | |
3078 | function also clears the basic block header and footer fields. | |
3079 | ||
3080 | This function is usually called after a pass (e.g. tracer) finishes | |
3081 | some transformations while in cfglayout mode. The required sequence | |
3082 | of the basic blocks is in a linked list along the bb->aux field. | |
3083 | This functions re-links the basic block prev_bb and next_bb pointers | |
532aafad SB |
3084 | accordingly, and it compacts and renumbers the blocks. |
3085 | ||
3086 | FIXME: This currently works only for RTL, but the only RTL-specific | |
3087 | bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved | |
3088 | to GIMPLE a long time ago, but it doesn't relink the basic block | |
3089 | chain. It could do that (to give better initial RTL) if this function | |
3090 | is made IR-agnostic (and moved to cfganal.c or cfg.c while at it). */ | |
78bde837 SB |
3091 | |
3092 | void | |
3093 | relink_block_chain (bool stay_in_cfglayout_mode) | |
3094 | { | |
3095 | basic_block bb, prev_bb; | |
3096 | int index; | |
3097 | ||
3098 | /* Maybe dump the re-ordered sequence. */ | |
3099 | if (dump_file) | |
3100 | { | |
3101 | fprintf (dump_file, "Reordered sequence:\n"); | |
3102 | for (bb = ENTRY_BLOCK_PTR->next_bb, index = NUM_FIXED_BLOCKS; | |
3103 | bb; | |
3104 | bb = (basic_block) bb->aux, index++) | |
3105 | { | |
3106 | fprintf (dump_file, " %i ", index); | |
3107 | if (get_bb_original (bb)) | |
3108 | fprintf (dump_file, "duplicate of %i ", | |
3109 | get_bb_original (bb)->index); | |
3110 | else if (forwarder_block_p (bb) | |
3111 | && !LABEL_P (BB_HEAD (bb))) | |
3112 | fprintf (dump_file, "compensation "); | |
3113 | else | |
3114 | fprintf (dump_file, "bb %i ", bb->index); | |
3115 | fprintf (dump_file, " [%i]\n", bb->frequency); | |
3116 | } | |
3117 | } | |
3118 | ||
3119 | /* Now reorder the blocks. */ | |
3120 | prev_bb = ENTRY_BLOCK_PTR; | |
3121 | bb = ENTRY_BLOCK_PTR->next_bb; | |
3122 | for (; bb; prev_bb = bb, bb = (basic_block) bb->aux) | |
3123 | { | |
3124 | bb->prev_bb = prev_bb; | |
3125 | prev_bb->next_bb = bb; | |
3126 | } | |
3127 | prev_bb->next_bb = EXIT_BLOCK_PTR; | |
3128 | EXIT_BLOCK_PTR->prev_bb = prev_bb; | |
3129 | ||
3130 | /* Then, clean up the aux fields. */ | |
3131 | FOR_ALL_BB (bb) | |
3132 | { | |
3133 | bb->aux = NULL; | |
3134 | if (!stay_in_cfglayout_mode) | |
3135 | BB_HEADER (bb) = BB_FOOTER (bb) = NULL; | |
3136 | } | |
3137 | ||
3138 | /* Maybe reset the original copy tables, they are not valid anymore | |
3139 | when we renumber the basic blocks in compact_blocks. If we are | |
3140 | are going out of cfglayout mode, don't re-allocate the tables. */ | |
3141 | free_original_copy_tables (); | |
3142 | if (stay_in_cfglayout_mode) | |
3143 | initialize_original_copy_tables (); | |
3144 | ||
3145 | /* Finally, put basic_block_info in the new order. */ | |
3146 | compact_blocks (); | |
3147 | } | |
3148 | \f | |
3149 | ||
3150 | /* Given a reorder chain, rearrange the code to match. */ | |
3151 | ||
3152 | static void | |
3153 | fixup_reorder_chain (void) | |
3154 | { | |
3155 | basic_block bb; | |
3156 | rtx insn = NULL; | |
3157 | ||
3158 | if (cfg_layout_function_header) | |
3159 | { | |
3160 | set_first_insn (cfg_layout_function_header); | |
3161 | insn = cfg_layout_function_header; | |
3162 | while (NEXT_INSN (insn)) | |
3163 | insn = NEXT_INSN (insn); | |
3164 | } | |
3165 | ||
3166 | /* First do the bulk reordering -- rechain the blocks without regard to | |
3167 | the needed changes to jumps and labels. */ | |
3168 | ||
3169 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb; bb = (basic_block) bb->aux) | |
3170 | { | |
3171 | if (BB_HEADER (bb)) | |
3172 | { | |
3173 | if (insn) | |
3174 | NEXT_INSN (insn) = BB_HEADER (bb); | |
3175 | else | |
3176 | set_first_insn (BB_HEADER (bb)); | |
3177 | PREV_INSN (BB_HEADER (bb)) = insn; | |
3178 | insn = BB_HEADER (bb); | |
3179 | while (NEXT_INSN (insn)) | |
3180 | insn = NEXT_INSN (insn); | |
3181 | } | |
3182 | if (insn) | |
3183 | NEXT_INSN (insn) = BB_HEAD (bb); | |
3184 | else | |
3185 | set_first_insn (BB_HEAD (bb)); | |
3186 | PREV_INSN (BB_HEAD (bb)) = insn; | |
3187 | insn = BB_END (bb); | |
3188 | if (BB_FOOTER (bb)) | |
3189 | { | |
3190 | NEXT_INSN (insn) = BB_FOOTER (bb); | |
3191 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
3192 | while (NEXT_INSN (insn)) | |
3193 | insn = NEXT_INSN (insn); | |
3194 | } | |
3195 | } | |
3196 | ||
3197 | NEXT_INSN (insn) = cfg_layout_function_footer; | |
3198 | if (cfg_layout_function_footer) | |
3199 | PREV_INSN (cfg_layout_function_footer) = insn; | |
3200 | ||
3201 | while (NEXT_INSN (insn)) | |
3202 | insn = NEXT_INSN (insn); | |
3203 | ||
3204 | set_last_insn (insn); | |
3205 | #ifdef ENABLE_CHECKING | |
3206 | verify_insn_chain (); | |
3207 | #endif | |
3208 | ||
3209 | /* Now add jumps and labels as needed to match the blocks new | |
3210 | outgoing edges. */ | |
3211 | ||
3212 | for (bb = ENTRY_BLOCK_PTR->next_bb; bb ; bb = (basic_block) bb->aux) | |
3213 | { | |
3214 | edge e_fall, e_taken, e; | |
3215 | rtx bb_end_insn; | |
3216 | rtx ret_label = NULL_RTX; | |
3217 | basic_block nb, src_bb; | |
3218 | edge_iterator ei; | |
3219 | ||
3220 | if (EDGE_COUNT (bb->succs) == 0) | |
3221 | continue; | |
3222 | ||
3223 | /* Find the old fallthru edge, and another non-EH edge for | |
3224 | a taken jump. */ | |
3225 | e_taken = e_fall = NULL; | |
3226 | ||
3227 | FOR_EACH_EDGE (e, ei, bb->succs) | |
3228 | if (e->flags & EDGE_FALLTHRU) | |
3229 | e_fall = e; | |
3230 | else if (! (e->flags & EDGE_EH)) | |
3231 | e_taken = e; | |
3232 | ||
3233 | bb_end_insn = BB_END (bb); | |
3234 | if (JUMP_P (bb_end_insn)) | |
3235 | { | |
3236 | ret_label = JUMP_LABEL (bb_end_insn); | |
3237 | if (any_condjump_p (bb_end_insn)) | |
3238 | { | |
3239 | /* This might happen if the conditional jump has side | |
3240 | effects and could therefore not be optimized away. | |
3241 | Make the basic block to end with a barrier in order | |
3242 | to prevent rtl_verify_flow_info from complaining. */ | |
3243 | if (!e_fall) | |
3244 | { | |
3245 | gcc_assert (!onlyjump_p (bb_end_insn) | |
3246 | || returnjump_p (bb_end_insn)); | |
3247 | BB_FOOTER (bb) = emit_barrier_after (bb_end_insn); | |
3248 | continue; | |
3249 | } | |
3250 | ||
3251 | /* If the old fallthru is still next, nothing to do. */ | |
3252 | if (bb->aux == e_fall->dest | |
3253 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3254 | continue; | |
3255 | ||
3256 | /* The degenerated case of conditional jump jumping to the next | |
3257 | instruction can happen for jumps with side effects. We need | |
3258 | to construct a forwarder block and this will be done just | |
3259 | fine by force_nonfallthru below. */ | |
3260 | if (!e_taken) | |
3261 | ; | |
3262 | ||
3263 | /* There is another special case: if *neither* block is next, | |
3264 | such as happens at the very end of a function, then we'll | |
3265 | need to add a new unconditional jump. Choose the taken | |
3266 | edge based on known or assumed probability. */ | |
3267 | else if (bb->aux != e_taken->dest) | |
3268 | { | |
3269 | rtx note = find_reg_note (bb_end_insn, REG_BR_PROB, 0); | |
3270 | ||
3271 | if (note | |
3272 | && INTVAL (XEXP (note, 0)) < REG_BR_PROB_BASE / 2 | |
3273 | && invert_jump (bb_end_insn, | |
3274 | (e_fall->dest == EXIT_BLOCK_PTR | |
3275 | ? NULL_RTX | |
3276 | : label_for_bb (e_fall->dest)), 0)) | |
3277 | { | |
3278 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3279 | gcc_checking_assert (could_fall_through | |
3280 | (e_taken->src, e_taken->dest)); | |
3281 | e_taken->flags |= EDGE_FALLTHRU; | |
3282 | update_br_prob_note (bb); | |
3283 | e = e_fall, e_fall = e_taken, e_taken = e; | |
3284 | } | |
3285 | } | |
3286 | ||
3287 | /* If the "jumping" edge is a crossing edge, and the fall | |
3288 | through edge is non-crossing, leave things as they are. */ | |
3289 | else if ((e_taken->flags & EDGE_CROSSING) | |
3290 | && !(e_fall->flags & EDGE_CROSSING)) | |
3291 | continue; | |
3292 | ||
3293 | /* Otherwise we can try to invert the jump. This will | |
3294 | basically never fail, however, keep up the pretense. */ | |
3295 | else if (invert_jump (bb_end_insn, | |
3296 | (e_fall->dest == EXIT_BLOCK_PTR | |
3297 | ? NULL_RTX | |
3298 | : label_for_bb (e_fall->dest)), 0)) | |
3299 | { | |
3300 | e_fall->flags &= ~EDGE_FALLTHRU; | |
3301 | gcc_checking_assert (could_fall_through | |
3302 | (e_taken->src, e_taken->dest)); | |
3303 | e_taken->flags |= EDGE_FALLTHRU; | |
3304 | update_br_prob_note (bb); | |
3305 | if (LABEL_NUSES (ret_label) == 0 | |
3306 | && single_pred_p (e_taken->dest)) | |
3307 | delete_insn (ret_label); | |
3308 | continue; | |
3309 | } | |
3310 | } | |
3311 | else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL) | |
3312 | { | |
3313 | /* If the old fallthru is still next or if | |
3314 | asm goto doesn't have a fallthru (e.g. when followed by | |
3315 | __builtin_unreachable ()), nothing to do. */ | |
3316 | if (! e_fall | |
3317 | || bb->aux == e_fall->dest | |
3318 | || e_fall->dest == EXIT_BLOCK_PTR) | |
3319 | continue; | |
3320 | ||
3321 | /* Otherwise we'll have to use the fallthru fixup below. */ | |
3322 | } | |
3323 | else | |
3324 | { | |
3325 | /* Otherwise we have some return, switch or computed | |
3326 | jump. In the 99% case, there should not have been a | |
3327 | fallthru edge. */ | |
3328 | gcc_assert (returnjump_p (bb_end_insn) || !e_fall); | |
3329 | continue; | |
3330 | } | |
3331 | } | |
3332 | else | |
3333 | { | |
3334 | /* No fallthru implies a noreturn function with EH edges, or | |
3335 | something similarly bizarre. In any case, we don't need to | |
3336 | do anything. */ | |
3337 | if (! e_fall) | |
3338 | continue; | |
3339 | ||
3340 | /* If the fallthru block is still next, nothing to do. */ | |
3341 | if (bb->aux == e_fall->dest) | |
3342 | continue; | |
3343 | ||
3344 | /* A fallthru to exit block. */ | |
3345 | if (e_fall->dest == EXIT_BLOCK_PTR) | |
3346 | continue; | |
3347 | } | |
3348 | ||
3349 | /* We got here if we need to add a new jump insn. | |
3350 | Note force_nonfallthru can delete E_FALL and thus we have to | |
3351 | save E_FALL->src prior to the call to force_nonfallthru. */ | |
3352 | src_bb = e_fall->src; | |
3353 | nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label); | |
3354 | if (nb) | |
3355 | { | |
3356 | nb->aux = bb->aux; | |
3357 | bb->aux = nb; | |
3358 | /* Don't process this new block. */ | |
3359 | bb = nb; | |
3360 | ||
3361 | /* Make sure new bb is tagged for correct section (same as | |
3362 | fall-thru source, since you cannot fall-thru across | |
3363 | section boundaries). */ | |
3364 | BB_COPY_PARTITION (src_bb, single_pred (bb)); | |
3365 | if (flag_reorder_blocks_and_partition | |
3366 | && targetm_common.have_named_sections | |
3367 | && JUMP_P (BB_END (bb)) | |
3368 | && !any_condjump_p (BB_END (bb)) | |
3369 | && (EDGE_SUCC (bb, 0)->flags & EDGE_CROSSING)) | |
3370 | add_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX); | |
3371 | } | |
3372 | } | |
3373 | ||
3374 | relink_block_chain (/*stay_in_cfglayout_mode=*/false); | |
3375 | ||
3376 | /* Annoying special case - jump around dead jumptables left in the code. */ | |
3377 | FOR_EACH_BB (bb) | |
3378 | { | |
3379 | edge e = find_fallthru_edge (bb->succs); | |
3380 | ||
3381 | if (e && !can_fallthru (e->src, e->dest)) | |
3382 | force_nonfallthru (e); | |
3383 | } | |
3384 | ||
3385 | /* Ensure goto_locus from edges has some instructions with that locus | |
3386 | in RTL. */ | |
3387 | if (!optimize) | |
3388 | FOR_EACH_BB (bb) | |
3389 | { | |
3390 | edge e; | |
3391 | edge_iterator ei; | |
3392 | ||
3393 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2f13f2de | 3394 | if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION |
5368224f | 3395 | && !(e->flags & EDGE_ABNORMAL)) |
78bde837 SB |
3396 | { |
3397 | edge e2; | |
3398 | edge_iterator ei2; | |
3399 | basic_block dest, nb; | |
3400 | rtx end; | |
3401 | ||
3402 | insn = BB_END (e->src); | |
3403 | end = PREV_INSN (BB_HEAD (e->src)); | |
3404 | while (insn != end | |
5368224f | 3405 | && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn))) |
78bde837 SB |
3406 | insn = PREV_INSN (insn); |
3407 | if (insn != end | |
5368224f | 3408 | && INSN_LOCATION (insn) == e->goto_locus) |
78bde837 SB |
3409 | continue; |
3410 | if (simplejump_p (BB_END (e->src)) | |
5368224f | 3411 | && !INSN_HAS_LOCATION (BB_END (e->src))) |
78bde837 | 3412 | { |
5368224f | 3413 | INSN_LOCATION (BB_END (e->src)) = e->goto_locus; |
78bde837 SB |
3414 | continue; |
3415 | } | |
3416 | dest = e->dest; | |
3417 | if (dest == EXIT_BLOCK_PTR) | |
3418 | { | |
3419 | /* Non-fallthru edges to the exit block cannot be split. */ | |
3420 | if (!(e->flags & EDGE_FALLTHRU)) | |
3421 | continue; | |
3422 | } | |
3423 | else | |
3424 | { | |
3425 | insn = BB_HEAD (dest); | |
3426 | end = NEXT_INSN (BB_END (dest)); | |
3427 | while (insn != end && !NONDEBUG_INSN_P (insn)) | |
3428 | insn = NEXT_INSN (insn); | |
5368224f DC |
3429 | if (insn != end && INSN_HAS_LOCATION (insn) |
3430 | && INSN_LOCATION (insn) == e->goto_locus) | |
78bde837 SB |
3431 | continue; |
3432 | } | |
3433 | nb = split_edge (e); | |
3434 | if (!INSN_P (BB_END (nb))) | |
3435 | BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), | |
3436 | nb); | |
5368224f | 3437 | INSN_LOCATION (BB_END (nb)) = e->goto_locus; |
78bde837 SB |
3438 | |
3439 | /* If there are other incoming edges to the destination block | |
3440 | with the same goto locus, redirect them to the new block as | |
3441 | well, this can prevent other such blocks from being created | |
3442 | in subsequent iterations of the loop. */ | |
3443 | for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) | |
2f13f2de | 3444 | if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION |
78bde837 | 3445 | && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) |
5368224f | 3446 | && e->goto_locus == e2->goto_locus) |
78bde837 SB |
3447 | redirect_edge_and_branch (e2, nb); |
3448 | else | |
3449 | ei_next (&ei2); | |
3450 | } | |
3451 | } | |
3452 | } | |
3453 | \f | |
3454 | /* Perform sanity checks on the insn chain. | |
3455 | 1. Check that next/prev pointers are consistent in both the forward and | |
3456 | reverse direction. | |
3457 | 2. Count insns in chain, going both directions, and check if equal. | |
3458 | 3. Check that get_last_insn () returns the actual end of chain. */ | |
3459 | ||
3460 | DEBUG_FUNCTION void | |
3461 | verify_insn_chain (void) | |
3462 | { | |
3463 | rtx x, prevx, nextx; | |
3464 | int insn_cnt1, insn_cnt2; | |
3465 | ||
3466 | for (prevx = NULL, insn_cnt1 = 1, x = get_insns (); | |
3467 | x != 0; | |
3468 | prevx = x, insn_cnt1++, x = NEXT_INSN (x)) | |
3469 | gcc_assert (PREV_INSN (x) == prevx); | |
3470 | ||
3471 | gcc_assert (prevx == get_last_insn ()); | |
3472 | ||
3473 | for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn (); | |
3474 | x != 0; | |
3475 | nextx = x, insn_cnt2++, x = PREV_INSN (x)) | |
3476 | gcc_assert (NEXT_INSN (x) == nextx); | |
3477 | ||
3478 | gcc_assert (insn_cnt1 == insn_cnt2); | |
3479 | } | |
3480 | \f | |
3481 | /* If we have assembler epilogues, the block falling through to exit must | |
3482 | be the last one in the reordered chain when we reach final. Ensure | |
3483 | that this condition is met. */ | |
3484 | static void | |
3485 | fixup_fallthru_exit_predecessor (void) | |
3486 | { | |
3487 | edge e; | |
3488 | basic_block bb = NULL; | |
3489 | ||
3490 | /* This transformation is not valid before reload, because we might | |
3491 | separate a call from the instruction that copies the return | |
3492 | value. */ | |
3493 | gcc_assert (reload_completed); | |
3494 | ||
3495 | e = find_fallthru_edge (EXIT_BLOCK_PTR->preds); | |
3496 | if (e) | |
3497 | bb = e->src; | |
3498 | ||
3499 | if (bb && bb->aux) | |
3500 | { | |
3501 | basic_block c = ENTRY_BLOCK_PTR->next_bb; | |
3502 | ||
3503 | /* If the very first block is the one with the fall-through exit | |
3504 | edge, we have to split that block. */ | |
3505 | if (c == bb) | |
3506 | { | |
3507 | bb = split_block (bb, NULL)->dest; | |
3508 | bb->aux = c->aux; | |
3509 | c->aux = bb; | |
3510 | BB_FOOTER (bb) = BB_FOOTER (c); | |
3511 | BB_FOOTER (c) = NULL; | |
3512 | } | |
3513 | ||
3514 | while (c->aux != bb) | |
3515 | c = (basic_block) c->aux; | |
3516 | ||
3517 | c->aux = bb->aux; | |
3518 | while (c->aux) | |
3519 | c = (basic_block) c->aux; | |
3520 | ||
3521 | c->aux = bb; | |
3522 | bb->aux = NULL; | |
3523 | } | |
3524 | } | |
3525 | ||
3526 | /* In case there are more than one fallthru predecessors of exit, force that | |
3527 | there is only one. */ | |
3528 | ||
3529 | static void | |
3530 | force_one_exit_fallthru (void) | |
3531 | { | |
3532 | edge e, predecessor = NULL; | |
3533 | bool more = false; | |
3534 | edge_iterator ei; | |
3535 | basic_block forwarder, bb; | |
3536 | ||
3537 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) | |
3538 | if (e->flags & EDGE_FALLTHRU) | |
3539 | { | |
3540 | if (predecessor == NULL) | |
3541 | predecessor = e; | |
3542 | else | |
3543 | { | |
3544 | more = true; | |
3545 | break; | |
3546 | } | |
3547 | } | |
3548 | ||
3549 | if (!more) | |
3550 | return; | |
3551 | ||
3552 | /* Exit has several fallthru predecessors. Create a forwarder block for | |
3553 | them. */ | |
3554 | forwarder = split_edge (predecessor); | |
3555 | for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); ) | |
3556 | { | |
3557 | if (e->src == forwarder | |
3558 | || !(e->flags & EDGE_FALLTHRU)) | |
3559 | ei_next (&ei); | |
3560 | else | |
3561 | redirect_edge_and_branch_force (e, forwarder); | |
3562 | } | |
3563 | ||
3564 | /* Fix up the chain of blocks -- make FORWARDER immediately precede the | |
3565 | exit block. */ | |
3566 | FOR_EACH_BB (bb) | |
3567 | { | |
3568 | if (bb->aux == NULL && bb != forwarder) | |
3569 | { | |
3570 | bb->aux = forwarder; | |
3571 | break; | |
3572 | } | |
3573 | } | |
3574 | } | |
3575 | \f | |
3576 | /* Return true in case it is possible to duplicate the basic block BB. */ | |
3577 | ||
3578 | static bool | |
3579 | cfg_layout_can_duplicate_bb_p (const_basic_block bb) | |
3580 | { | |
3581 | /* Do not attempt to duplicate tablejumps, as we need to unshare | |
3582 | the dispatch table. This is difficult to do, as the instructions | |
3583 | computing jump destination may be hoisted outside the basic block. */ | |
3584 | if (tablejump_p (BB_END (bb), NULL, NULL)) | |
3585 | return false; | |
3586 | ||
3587 | /* Do not duplicate blocks containing insns that can't be copied. */ | |
3588 | if (targetm.cannot_copy_insn_p) | |
3589 | { | |
3590 | rtx insn = BB_HEAD (bb); | |
3591 | while (1) | |
3592 | { | |
3593 | if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn)) | |
3594 | return false; | |
3595 | if (insn == BB_END (bb)) | |
3596 | break; | |
3597 | insn = NEXT_INSN (insn); | |
3598 | } | |
3599 | } | |
3600 | ||
3601 | return true; | |
3602 | } | |
3603 | ||
3604 | rtx | |
3605 | duplicate_insn_chain (rtx from, rtx to) | |
3606 | { | |
3607 | rtx insn, last, copy; | |
3608 | ||
3609 | /* Avoid updating of boundaries of previous basic block. The | |
3610 | note will get removed from insn stream in fixup. */ | |
3611 | last = emit_note (NOTE_INSN_DELETED); | |
3612 | ||
3613 | /* Create copy at the end of INSN chain. The chain will | |
3614 | be reordered later. */ | |
3615 | for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn)) | |
3616 | { | |
3617 | switch (GET_CODE (insn)) | |
3618 | { | |
3619 | case DEBUG_INSN: | |
3620 | /* Don't duplicate label debug insns. */ | |
3621 | if (TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL) | |
3622 | break; | |
3623 | /* FALLTHRU */ | |
3624 | case INSN: | |
3625 | case CALL_INSN: | |
3626 | case JUMP_INSN: | |
3627 | /* Avoid copying of dispatch tables. We never duplicate | |
3628 | tablejumps, so this can hit only in case the table got | |
3629 | moved far from original jump. */ | |
34f0d87a | 3630 | if (JUMP_TABLE_DATA_P (insn)) |
78bde837 SB |
3631 | { |
3632 | /* Avoid copying following barrier as well if any | |
3633 | (and debug insns in between). */ | |
3634 | rtx next; | |
3635 | ||
3636 | for (next = NEXT_INSN (insn); | |
3637 | next != NEXT_INSN (to); | |
3638 | next = NEXT_INSN (next)) | |
3639 | if (!DEBUG_INSN_P (next)) | |
3640 | break; | |
3641 | if (next != NEXT_INSN (to) && BARRIER_P (next)) | |
3642 | insn = next; | |
3643 | break; | |
3644 | } | |
3645 | copy = emit_copy_of_insn_after (insn, get_last_insn ()); | |
3646 | if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX | |
3647 | && ANY_RETURN_P (JUMP_LABEL (insn))) | |
3648 | JUMP_LABEL (copy) = JUMP_LABEL (insn); | |
3649 | maybe_copy_prologue_epilogue_insn (insn, copy); | |
3650 | break; | |
3651 | ||
3652 | case CODE_LABEL: | |
3653 | break; | |
3654 | ||
3655 | case BARRIER: | |
3656 | emit_barrier (); | |
3657 | break; | |
3658 | ||
3659 | case NOTE: | |
3660 | switch (NOTE_KIND (insn)) | |
3661 | { | |
3662 | /* In case prologue is empty and function contain label | |
3663 | in first BB, we may want to copy the block. */ | |
3664 | case NOTE_INSN_PROLOGUE_END: | |
3665 | ||
3666 | case NOTE_INSN_DELETED: | |
3667 | case NOTE_INSN_DELETED_LABEL: | |
3668 | case NOTE_INSN_DELETED_DEBUG_LABEL: | |
3669 | /* No problem to strip these. */ | |
3670 | case NOTE_INSN_FUNCTION_BEG: | |
3671 | /* There is always just single entry to function. */ | |
3672 | case NOTE_INSN_BASIC_BLOCK: | |
3673 | break; | |
3674 | ||
3675 | case NOTE_INSN_EPILOGUE_BEG: | |
3676 | case NOTE_INSN_SWITCH_TEXT_SECTIONS: | |
3677 | emit_note_copy (insn); | |
3678 | break; | |
3679 | ||
3680 | default: | |
3681 | /* All other notes should have already been eliminated. */ | |
3682 | gcc_unreachable (); | |
3683 | } | |
3684 | break; | |
3685 | default: | |
3686 | gcc_unreachable (); | |
3687 | } | |
3688 | } | |
3689 | insn = NEXT_INSN (last); | |
3690 | delete_insn (last); | |
3691 | return insn; | |
3692 | } | |
3693 | ||
3694 | /* Create a duplicate of the basic block BB. */ | |
3695 | ||
3696 | static basic_block | |
3697 | cfg_layout_duplicate_bb (basic_block bb) | |
3698 | { | |
3699 | rtx insn; | |
3700 | basic_block new_bb; | |
3701 | ||
3702 | insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb)); | |
3703 | new_bb = create_basic_block (insn, | |
3704 | insn ? get_last_insn () : NULL, | |
3705 | EXIT_BLOCK_PTR->prev_bb); | |
3706 | ||
3707 | BB_COPY_PARTITION (new_bb, bb); | |
3708 | if (BB_HEADER (bb)) | |
3709 | { | |
3710 | insn = BB_HEADER (bb); | |
3711 | while (NEXT_INSN (insn)) | |
3712 | insn = NEXT_INSN (insn); | |
3713 | insn = duplicate_insn_chain (BB_HEADER (bb), insn); | |
3714 | if (insn) | |
3715 | BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3716 | } | |
3717 | ||
3718 | if (BB_FOOTER (bb)) | |
3719 | { | |
3720 | insn = BB_FOOTER (bb); | |
3721 | while (NEXT_INSN (insn)) | |
3722 | insn = NEXT_INSN (insn); | |
3723 | insn = duplicate_insn_chain (BB_FOOTER (bb), insn); | |
3724 | if (insn) | |
3725 | BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ()); | |
3726 | } | |
3727 | ||
3728 | return new_bb; | |
3729 | } | |
3730 | ||
3731 | \f | |
3732 | /* Main entry point to this module - initialize the datastructures for | |
3733 | CFG layout changes. It keeps LOOPS up-to-date if not null. | |
3734 | ||
3735 | FLAGS is a set of additional flags to pass to cleanup_cfg(). */ | |
3736 | ||
3737 | void | |
3738 | cfg_layout_initialize (unsigned int flags) | |
3739 | { | |
3740 | rtx x; | |
3741 | basic_block bb; | |
3742 | ||
3743 | initialize_original_copy_tables (); | |
3744 | ||
3745 | cfg_layout_rtl_register_cfg_hooks (); | |
3746 | ||
3747 | record_effective_endpoints (); | |
3748 | ||
3749 | /* Make sure that the targets of non local gotos are marked. */ | |
3750 | for (x = nonlocal_goto_handler_labels; x; x = XEXP (x, 1)) | |
3751 | { | |
3752 | bb = BLOCK_FOR_INSN (XEXP (x, 0)); | |
3753 | bb->flags |= BB_NON_LOCAL_GOTO_TARGET; | |
3754 | } | |
3755 | ||
3756 | cleanup_cfg (CLEANUP_CFGLAYOUT | flags); | |
3757 | } | |
3758 | ||
3759 | /* Splits superblocks. */ | |
3760 | void | |
3761 | break_superblocks (void) | |
3762 | { | |
3763 | sbitmap superblocks; | |
3764 | bool need = false; | |
3765 | basic_block bb; | |
3766 | ||
3767 | superblocks = sbitmap_alloc (last_basic_block); | |
f61e445a | 3768 | bitmap_clear (superblocks); |
78bde837 SB |
3769 | |
3770 | FOR_EACH_BB (bb) | |
3771 | if (bb->flags & BB_SUPERBLOCK) | |
3772 | { | |
3773 | bb->flags &= ~BB_SUPERBLOCK; | |
d7c028c0 | 3774 | bitmap_set_bit (superblocks, bb->index); |
78bde837 SB |
3775 | need = true; |
3776 | } | |
3777 | ||
3778 | if (need) | |
3779 | { | |
3780 | rebuild_jump_labels (get_insns ()); | |
3781 | find_many_sub_basic_blocks (superblocks); | |
3782 | } | |
3783 | ||
3784 | free (superblocks); | |
3785 | } | |
3786 | ||
3787 | /* Finalize the changes: reorder insn list according to the sequence specified | |
3788 | by aux pointers, enter compensation code, rebuild scope forest. */ | |
3789 | ||
3790 | void | |
3791 | cfg_layout_finalize (void) | |
3792 | { | |
3793 | #ifdef ENABLE_CHECKING | |
3794 | verify_flow_info (); | |
3795 | #endif | |
3796 | force_one_exit_fallthru (); | |
3797 | rtl_register_cfg_hooks (); | |
3798 | if (reload_completed | |
3799 | #ifdef HAVE_epilogue | |
3800 | && !HAVE_epilogue | |
3801 | #endif | |
3802 | ) | |
3803 | fixup_fallthru_exit_predecessor (); | |
3804 | fixup_reorder_chain (); | |
3805 | ||
3806 | rebuild_jump_labels (get_insns ()); | |
3807 | delete_dead_jumptables (); | |
3808 | ||
3809 | #ifdef ENABLE_CHECKING | |
3810 | verify_insn_chain (); | |
3811 | verify_flow_info (); | |
3812 | #endif | |
3813 | } | |
3814 | ||
ba5e9aca | 3815 | |
9ee634e3 | 3816 | /* Same as split_block but update cfg_layout structures. */ |
f470c378 ZD |
3817 | |
3818 | static basic_block | |
d329e058 | 3819 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 | 3820 | { |
ae50c0cb | 3821 | rtx insn = (rtx) insnp; |
f470c378 | 3822 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 3823 | |
bcc708fc MM |
3824 | BB_FOOTER (new_bb) = BB_FOOTER (bb); |
3825 | BB_FOOTER (bb) = NULL; | |
9ee634e3 | 3826 | |
f470c378 | 3827 | return new_bb; |
9ee634e3 JH |
3828 | } |
3829 | ||
9ee634e3 | 3830 | /* Redirect Edge to DEST. */ |
6de9cd9a | 3831 | static edge |
d329e058 | 3832 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
3833 | { |
3834 | basic_block src = e->src; | |
6de9cd9a | 3835 | edge ret; |
9ee634e3 | 3836 | |
bc35512f | 3837 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 3838 | return NULL; |
bc35512f | 3839 | |
3348b696 | 3840 | if (e->dest == dest) |
6de9cd9a | 3841 | return e; |
bc35512f | 3842 | |
3348b696 | 3843 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a | 3844 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a | 3845 | { |
6fb5fa3c | 3846 | df_set_bb_dirty (src); |
6de9cd9a | 3847 | return ret; |
f345f21a | 3848 | } |
bc35512f JH |
3849 | |
3850 | if (e->src == ENTRY_BLOCK_PTR | |
3851 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) | |
3852 | { | |
c263766c RH |
3853 | if (dump_file) |
3854 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
3855 | e->src->index, dest->index); |
3856 | ||
6fb5fa3c | 3857 | df_set_bb_dirty (e->src); |
bc35512f | 3858 | redirect_edge_succ (e, dest); |
6de9cd9a | 3859 | return e; |
bc35512f JH |
3860 | } |
3861 | ||
9ee634e3 JH |
3862 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
3863 | in the case the basic block appears to be in sequence. Avoid this | |
3864 | transformation. */ | |
3865 | ||
9ee634e3 JH |
3866 | if (e->flags & EDGE_FALLTHRU) |
3867 | { | |
3868 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 3869 | if (JUMP_P (BB_END (src)) |
432f982f JH |
3870 | && label_is_jump_target_p (BB_HEAD (e->dest), |
3871 | BB_END (src))) | |
9ee634e3 | 3872 | { |
341c100f | 3873 | edge redirected; |
c22cacf3 | 3874 | |
c263766c RH |
3875 | if (dump_file) |
3876 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
3877 | "%i->%i redirected to %i\n", |
3878 | e->src->index, e->dest->index, dest->index); | |
3879 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
3880 | redirected = redirect_branch_edge (e, dest); |
3881 | gcc_assert (redirected); | |
0c617be4 JL |
3882 | redirected->flags |= EDGE_FALLTHRU; |
3883 | df_set_bb_dirty (redirected->src); | |
3884 | return redirected; | |
9ee634e3 JH |
3885 | } |
3886 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 3887 | of conditional jump, remove it. */ |
628f6a4e | 3888 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 3889 | { |
03101c6f KH |
3890 | /* Find the edge that is different from E. */ |
3891 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 3892 | |
9ee634e3 | 3893 | if (s->dest == dest |
a813c111 SB |
3894 | && any_condjump_p (BB_END (src)) |
3895 | && onlyjump_p (BB_END (src))) | |
3896 | delete_insn (BB_END (src)); | |
9ee634e3 | 3897 | } |
c263766c | 3898 | if (dump_file) |
dc764d10 | 3899 | fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n", |
bc35512f | 3900 | e->src->index, e->dest->index, dest->index); |
0c617be4 | 3901 | ret = redirect_edge_succ_nodup (e, dest); |
9ee634e3 JH |
3902 | } |
3903 | else | |
bc35512f | 3904 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
3905 | |
3906 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
341c100f | 3907 | gcc_assert (!simplejump_p (BB_END (src))); |
9ee634e3 | 3908 | |
6fb5fa3c | 3909 | df_set_bb_dirty (src); |
9ee634e3 JH |
3910 | return ret; |
3911 | } | |
3912 | ||
3913 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
3914 | static basic_block | |
d329e058 | 3915 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 3916 | { |
341c100f NS |
3917 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
3918 | ||
3919 | gcc_assert (redirected); | |
9ee634e3 JH |
3920 | return NULL; |
3921 | } | |
3922 | ||
f470c378 ZD |
3923 | /* Same as delete_basic_block but update cfg_layout structures. */ |
3924 | ||
9ee634e3 | 3925 | static void |
d329e058 | 3926 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 3927 | { |
a813c111 | 3928 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 3929 | |
bcc708fc | 3930 | if (BB_HEADER (bb)) |
9ee634e3 | 3931 | { |
a813c111 | 3932 | next = BB_HEAD (bb); |
9ee634e3 | 3933 | if (prev) |
bcc708fc | 3934 | NEXT_INSN (prev) = BB_HEADER (bb); |
9ee634e3 | 3935 | else |
bcc708fc MM |
3936 | set_first_insn (BB_HEADER (bb)); |
3937 | PREV_INSN (BB_HEADER (bb)) = prev; | |
3938 | insn = BB_HEADER (bb); | |
9ee634e3 JH |
3939 | while (NEXT_INSN (insn)) |
3940 | insn = NEXT_INSN (insn); | |
3941 | NEXT_INSN (insn) = next; | |
3942 | PREV_INSN (next) = insn; | |
3943 | } | |
a813c111 | 3944 | next = NEXT_INSN (BB_END (bb)); |
bcc708fc | 3945 | if (BB_FOOTER (bb)) |
9ee634e3 | 3946 | { |
bcc708fc | 3947 | insn = BB_FOOTER (bb); |
bc35512f JH |
3948 | while (insn) |
3949 | { | |
4b4bf941 | 3950 | if (BARRIER_P (insn)) |
bc35512f JH |
3951 | { |
3952 | if (PREV_INSN (insn)) | |
3953 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
3954 | else | |
bcc708fc | 3955 | BB_FOOTER (bb) = NEXT_INSN (insn); |
bc35512f JH |
3956 | if (NEXT_INSN (insn)) |
3957 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
3958 | } | |
4b4bf941 | 3959 | if (LABEL_P (insn)) |
bc35512f JH |
3960 | break; |
3961 | insn = NEXT_INSN (insn); | |
3962 | } | |
bcc708fc | 3963 | if (BB_FOOTER (bb)) |
bc35512f | 3964 | { |
a813c111 | 3965 | insn = BB_END (bb); |
bcc708fc MM |
3966 | NEXT_INSN (insn) = BB_FOOTER (bb); |
3967 | PREV_INSN (BB_FOOTER (bb)) = insn; | |
bc35512f JH |
3968 | while (NEXT_INSN (insn)) |
3969 | insn = NEXT_INSN (insn); | |
3970 | NEXT_INSN (insn) = next; | |
3971 | if (next) | |
3972 | PREV_INSN (next) = insn; | |
3973 | else | |
3974 | set_last_insn (insn); | |
3975 | } | |
9ee634e3 JH |
3976 | } |
3977 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
bcc708fc | 3978 | to = &BB_HEADER (bb->next_bb); |
9ee634e3 JH |
3979 | else |
3980 | to = &cfg_layout_function_footer; | |
997de8ed | 3981 | |
9ee634e3 JH |
3982 | rtl_delete_block (bb); |
3983 | ||
3984 | if (prev) | |
3985 | prev = NEXT_INSN (prev); | |
d329e058 | 3986 | else |
9ee634e3 JH |
3987 | prev = get_insns (); |
3988 | if (next) | |
3989 | next = PREV_INSN (next); | |
d329e058 | 3990 | else |
9ee634e3 JH |
3991 | next = get_last_insn (); |
3992 | ||
3993 | if (next && NEXT_INSN (next) != prev) | |
3994 | { | |
3995 | remaints = unlink_insn_chain (prev, next); | |
3996 | insn = remaints; | |
3997 | while (NEXT_INSN (insn)) | |
3998 | insn = NEXT_INSN (insn); | |
3999 | NEXT_INSN (insn) = *to; | |
4000 | if (*to) | |
4001 | PREV_INSN (*to) = insn; | |
4002 | *to = remaints; | |
4003 | } | |
4004 | } | |
4005 | ||
beb235f8 | 4006 | /* Return true when blocks A and B can be safely merged. */ |
b48d0358 | 4007 | |
bc35512f | 4008 | static bool |
b48d0358 | 4009 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) |
bc35512f | 4010 | { |
750054a2 CT |
4011 | /* If we are partitioning hot/cold basic blocks, we don't want to |
4012 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
4013 | and cold sections. |
4014 | ||
8e8d5162 | 4015 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
4016 | be optimizable (or blocks that appear to be mergeable), but which really |
4017 | must be left untouched (they are required to make it safely across | |
4018 | partition boundaries). See the comments at the top of | |
8e8d5162 CT |
4019 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
4020 | ||
87c8b4be | 4021 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 4022 | return false; |
750054a2 | 4023 | |
7d776ee2 RG |
4024 | /* Protect the loop latches. */ |
4025 | if (current_loops && b->loop_father->latch == b) | |
4026 | return false; | |
4027 | ||
894a84b5 BS |
4028 | /* If we would end up moving B's instructions, make sure it doesn't fall |
4029 | through into the exit block, since we cannot recover from a fallthrough | |
4030 | edge into the exit block occurring in the middle of a function. */ | |
4031 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) | |
4032 | { | |
4033 | edge e = find_fallthru_edge (b->succs); | |
4034 | if (e && e->dest == EXIT_BLOCK_PTR) | |
4035 | return false; | |
4036 | } | |
4037 | ||
bc35512f | 4038 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
4039 | return (single_succ_p (a) |
4040 | && single_succ (a) == b | |
4041 | && single_pred_p (b) == 1 | |
628f6a4e | 4042 | && a != b |
bc35512f | 4043 | /* Must be simple edge. */ |
c5cbcccf | 4044 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f | 4045 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR |
49ea3702 SB |
4046 | /* If the jump insn has side effects, we can't kill the edge. |
4047 | When not optimizing, try_redirect_by_replacing_jump will | |
4048 | not allow us to redirect an edge by replacing a table jump. */ | |
4b4bf941 | 4049 | && (!JUMP_P (BB_END (a)) |
49ea3702 | 4050 | || ((!optimize || reload_completed) |
a813c111 | 4051 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
4052 | } |
4053 | ||
41806d92 NS |
4054 | /* Merge block A and B. The blocks must be mergeable. */ |
4055 | ||
bc35512f JH |
4056 | static void |
4057 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
4058 | { | |
50a36e42 | 4059 | bool forwarder_p = (b->flags & BB_FORWARDER_BLOCK) != 0; |
f9df6f16 | 4060 | rtx insn; |
50a36e42 | 4061 | |
77a74ed7 | 4062 | gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f | 4063 | |
6fb5fa3c | 4064 | if (dump_file) |
50a36e42 EB |
4065 | fprintf (dump_file, "Merging block %d into block %d...\n", b->index, |
4066 | a->index); | |
6fb5fa3c | 4067 | |
bc35512f | 4068 | /* If there was a CODE_LABEL beginning B, delete it. */ |
4b4bf941 | 4069 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 | 4070 | { |
2c97f8e4 RH |
4071 | delete_insn (BB_HEAD (b)); |
4072 | } | |
bc35512f JH |
4073 | |
4074 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
4075 | it cleaned up. */ | |
4b4bf941 | 4076 | if (JUMP_P (BB_END (a))) |
628f6a4e | 4077 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 4078 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f | 4079 | |
9be94227 | 4080 | /* When not optimizing CFG and the edge is the only place in RTL which holds |
7241571e | 4081 | some unique locus, emit a nop with that locus in between. */ |
9be94227 EB |
4082 | if (!optimize) |
4083 | emit_nop_for_unique_locus_between (a, b); | |
7241571e | 4084 | |
bc35512f | 4085 | /* Possible line number notes should appear in between. */ |
bcc708fc | 4086 | if (BB_HEADER (b)) |
bc35512f | 4087 | { |
a813c111 | 4088 | rtx first = BB_END (a), last; |
bc35512f | 4089 | |
bcc708fc | 4090 | last = emit_insn_after_noloc (BB_HEADER (b), BB_END (a), a); |
bd73623c JJ |
4091 | /* The above might add a BARRIER as BB_END, but as barriers |
4092 | aren't valid parts of a bb, remove_insn doesn't update | |
4093 | BB_END if it is a barrier. So adjust BB_END here. */ | |
4094 | while (BB_END (a) != first && BARRIER_P (BB_END (a))) | |
4095 | BB_END (a) = PREV_INSN (BB_END (a)); | |
a7b87f73 | 4096 | delete_insn_chain (NEXT_INSN (first), last, false); |
bcc708fc | 4097 | BB_HEADER (b) = NULL; |
bc35512f JH |
4098 | } |
4099 | ||
4100 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 4101 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 4102 | { |
f9df6f16 | 4103 | insn = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
6c3d0e31 | 4104 | |
f9df6f16 | 4105 | emit_insn_after_noloc (insn, BB_END (a), a); |
bc35512f JH |
4106 | } |
4107 | /* Otherwise just re-associate the instructions. */ | |
4108 | else | |
4109 | { | |
a813c111 | 4110 | insn = BB_HEAD (b); |
a813c111 | 4111 | BB_END (a) = BB_END (b); |
bc35512f JH |
4112 | } |
4113 | ||
f9df6f16 JJ |
4114 | /* emit_insn_after_noloc doesn't call df_insn_change_bb. |
4115 | We need to explicitly call. */ | |
4116 | update_bb_for_insn_chain (insn, BB_END (b), a); | |
4117 | ||
4118 | /* Skip possible DELETED_LABEL insn. */ | |
4119 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
4120 | insn = NEXT_INSN (insn); | |
4121 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); | |
4122 | BB_HEAD (b) = NULL; | |
4123 | delete_insn (insn); | |
4124 | ||
6fb5fa3c DB |
4125 | df_bb_delete (b->index); |
4126 | ||
bc35512f | 4127 | /* Possible tablejumps and barriers should appear after the block. */ |
bcc708fc | 4128 | if (BB_FOOTER (b)) |
bc35512f | 4129 | { |
bcc708fc MM |
4130 | if (!BB_FOOTER (a)) |
4131 | BB_FOOTER (a) = BB_FOOTER (b); | |
bc35512f JH |
4132 | else |
4133 | { | |
bcc708fc | 4134 | rtx last = BB_FOOTER (a); |
bc35512f JH |
4135 | |
4136 | while (NEXT_INSN (last)) | |
4137 | last = NEXT_INSN (last); | |
bcc708fc MM |
4138 | NEXT_INSN (last) = BB_FOOTER (b); |
4139 | PREV_INSN (BB_FOOTER (b)) = last; | |
bc35512f | 4140 | } |
bcc708fc | 4141 | BB_FOOTER (b) = NULL; |
bc35512f JH |
4142 | } |
4143 | ||
50a36e42 | 4144 | /* If B was a forwarder block, propagate the locus on the edge. */ |
2f13f2de | 4145 | if (forwarder_p |
fbc68f2a | 4146 | && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION) |
50a36e42 EB |
4147 | EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus; |
4148 | ||
c263766c | 4149 | if (dump_file) |
50a36e42 | 4150 | fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index); |
bc35512f JH |
4151 | } |
4152 | ||
4153 | /* Split edge E. */ | |
f470c378 | 4154 | |
bc35512f JH |
4155 | static basic_block |
4156 | cfg_layout_split_edge (edge e) | |
4157 | { | |
bc35512f JH |
4158 | basic_block new_bb = |
4159 | create_basic_block (e->src != ENTRY_BLOCK_PTR | |
a813c111 | 4160 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
4161 | NULL_RTX, e->src); |
4162 | ||
3e7eb734 JJ |
4163 | if (e->dest == EXIT_BLOCK_PTR) |
4164 | BB_COPY_PARTITION (new_bb, e->src); | |
4165 | else | |
4166 | BB_COPY_PARTITION (new_bb, e->dest); | |
a9b2ee88 | 4167 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
4168 | redirect_edge_and_branch_force (e, new_bb); |
4169 | ||
4170 | return new_bb; | |
4171 | } | |
4172 | ||
f470c378 ZD |
4173 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
4174 | ||
4175 | static void | |
4176 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
4177 | { | |
4178 | } | |
4179 | ||
df92c640 SB |
4180 | /* Return true if BB contains only labels or non-executable |
4181 | instructions. */ | |
4182 | ||
4183 | static bool | |
4184 | rtl_block_empty_p (basic_block bb) | |
4185 | { | |
4186 | rtx insn; | |
4187 | ||
4188 | if (bb == ENTRY_BLOCK_PTR || bb == EXIT_BLOCK_PTR) | |
4189 | return true; | |
4190 | ||
4191 | FOR_BB_INSNS (bb, insn) | |
4192 | if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn)) | |
4193 | return false; | |
4194 | ||
4195 | return true; | |
4196 | } | |
4197 | ||
4198 | /* Split a basic block if it ends with a conditional branch and if | |
4199 | the other part of the block is not empty. */ | |
4200 | ||
4201 | static basic_block | |
4202 | rtl_split_block_before_cond_jump (basic_block bb) | |
4203 | { | |
4204 | rtx insn; | |
4205 | rtx split_point = NULL; | |
4206 | rtx last = NULL; | |
4207 | bool found_code = false; | |
4208 | ||
4209 | FOR_BB_INSNS (bb, insn) | |
4210 | { | |
4211 | if (any_condjump_p (insn)) | |
4212 | split_point = last; | |
4213 | else if (NONDEBUG_INSN_P (insn)) | |
4214 | found_code = true; | |
4215 | last = insn; | |
4216 | } | |
4217 | ||
4218 | /* Did not find everything. */ | |
4219 | if (found_code && split_point) | |
4220 | return split_block (bb, split_point)->dest; | |
4221 | else | |
4222 | return NULL; | |
4223 | } | |
4224 | ||
6de9cd9a DN |
4225 | /* Return 1 if BB ends with a call, possibly followed by some |
4226 | instructions that must stay with the call, 0 otherwise. */ | |
4227 | ||
4228 | static bool | |
b48d0358 | 4229 | rtl_block_ends_with_call_p (basic_block bb) |
6de9cd9a DN |
4230 | { |
4231 | rtx insn = BB_END (bb); | |
4232 | ||
4b4bf941 | 4233 | while (!CALL_P (insn) |
6de9cd9a | 4234 | && insn != BB_HEAD (bb) |
92ddef69 | 4235 | && (keep_with_call_p (insn) |
b5b8b0ac AO |
4236 | || NOTE_P (insn) |
4237 | || DEBUG_INSN_P (insn))) | |
6de9cd9a | 4238 | insn = PREV_INSN (insn); |
4b4bf941 | 4239 | return (CALL_P (insn)); |
6de9cd9a DN |
4240 | } |
4241 | ||
4242 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
4243 | ||
4244 | static bool | |
9678086d | 4245 | rtl_block_ends_with_condjump_p (const_basic_block bb) |
6de9cd9a DN |
4246 | { |
4247 | return any_condjump_p (BB_END (bb)); | |
4248 | } | |
4249 | ||
4250 | /* Return true if we need to add fake edge to exit. | |
4251 | Helper function for rtl_flow_call_edges_add. */ | |
4252 | ||
4253 | static bool | |
9678086d | 4254 | need_fake_edge_p (const_rtx insn) |
6de9cd9a DN |
4255 | { |
4256 | if (!INSN_P (insn)) | |
4257 | return false; | |
4258 | ||
4b4bf941 | 4259 | if ((CALL_P (insn) |
6de9cd9a DN |
4260 | && !SIBLING_CALL_P (insn) |
4261 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
becfd6e5 | 4262 | && !(RTL_CONST_OR_PURE_CALL_P (insn)))) |
6de9cd9a DN |
4263 | return true; |
4264 | ||
4265 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
4266 | && MEM_VOLATILE_P (PATTERN (insn))) | |
4267 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
4268 | && asm_noperands (insn) != -1 | |
4269 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
4270 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
4271 | } | |
4272 | ||
4273 | /* Add fake edges to the function exit for any non constant and non noreturn | |
4274 | calls, volatile inline assembly in the bitmap of blocks specified by | |
4275 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
4276 | that were split. | |
4277 | ||
4278 | The goal is to expose cases in which entering a basic block does not imply | |
4279 | that all subsequent instructions must be executed. */ | |
4280 | ||
4281 | static int | |
4282 | rtl_flow_call_edges_add (sbitmap blocks) | |
4283 | { | |
4284 | int i; | |
4285 | int blocks_split = 0; | |
4286 | int last_bb = last_basic_block; | |
4287 | bool check_last_block = false; | |
4288 | ||
24bd1a0b | 4289 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
4290 | return 0; |
4291 | ||
4292 | if (! blocks) | |
4293 | check_last_block = true; | |
4294 | else | |
d7c028c0 | 4295 | check_last_block = bitmap_bit_p (blocks, EXIT_BLOCK_PTR->prev_bb->index); |
6de9cd9a DN |
4296 | |
4297 | /* In the last basic block, before epilogue generation, there will be | |
4298 | a fallthru edge to EXIT. Special care is required if the last insn | |
4299 | of the last basic block is a call because make_edge folds duplicate | |
4300 | edges, which would result in the fallthru edge also being marked | |
4301 | fake, which would result in the fallthru edge being removed by | |
4302 | remove_fake_edges, which would result in an invalid CFG. | |
4303 | ||
4304 | Moreover, we can't elide the outgoing fake edge, since the block | |
4305 | profiler needs to take this into account in order to solve the minimal | |
4306 | spanning tree in the case that the call doesn't return. | |
4307 | ||
4308 | Handle this by adding a dummy instruction in a new last basic block. */ | |
4309 | if (check_last_block) | |
4310 | { | |
4311 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
4312 | rtx insn = BB_END (bb); | |
4313 | ||
4314 | /* Back up past insns that must be kept in the same block as a call. */ | |
4315 | while (insn != BB_HEAD (bb) | |
4316 | && keep_with_call_p (insn)) | |
4317 | insn = PREV_INSN (insn); | |
4318 | ||
4319 | if (need_fake_edge_p (insn)) | |
4320 | { | |
4321 | edge e; | |
4322 | ||
9ff3d2de JL |
4323 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4324 | if (e) | |
4325 | { | |
c41c1387 | 4326 | insert_insn_on_edge (gen_use (const0_rtx), e); |
9ff3d2de JL |
4327 | commit_edge_insertions (); |
4328 | } | |
6de9cd9a DN |
4329 | } |
4330 | } | |
4331 | ||
4332 | /* Now add fake edges to the function exit for any non constant | |
4333 | calls since there is no way that we can determine if they will | |
4334 | return or not... */ | |
4335 | ||
24bd1a0b | 4336 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a DN |
4337 | { |
4338 | basic_block bb = BASIC_BLOCK (i); | |
4339 | rtx insn; | |
4340 | rtx prev_insn; | |
4341 | ||
4342 | if (!bb) | |
4343 | continue; | |
4344 | ||
d7c028c0 | 4345 | if (blocks && !bitmap_bit_p (blocks, i)) |
6de9cd9a DN |
4346 | continue; |
4347 | ||
4348 | for (insn = BB_END (bb); ; insn = prev_insn) | |
4349 | { | |
4350 | prev_insn = PREV_INSN (insn); | |
4351 | if (need_fake_edge_p (insn)) | |
4352 | { | |
4353 | edge e; | |
4354 | rtx split_at_insn = insn; | |
4355 | ||
4356 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 4357 | remain in the same block as the call. */ |
4b4bf941 | 4358 | if (CALL_P (insn)) |
6de9cd9a DN |
4359 | while (split_at_insn != BB_END (bb) |
4360 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
4361 | split_at_insn = NEXT_INSN (split_at_insn); | |
4362 | ||
4363 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 4364 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
4365 | block in CFG already. Calling make_edge in such case would |
4366 | cause us to mark that edge as fake and remove it later. */ | |
4367 | ||
4368 | #ifdef ENABLE_CHECKING | |
4369 | if (split_at_insn == BB_END (bb)) | |
628f6a4e | 4370 | { |
9ff3d2de JL |
4371 | e = find_edge (bb, EXIT_BLOCK_PTR); |
4372 | gcc_assert (e == NULL); | |
628f6a4e | 4373 | } |
6de9cd9a DN |
4374 | #endif |
4375 | ||
4376 | /* Note that the following may create a new basic block | |
4377 | and renumber the existing basic blocks. */ | |
4378 | if (split_at_insn != BB_END (bb)) | |
4379 | { | |
4380 | e = split_block (bb, split_at_insn); | |
4381 | if (e) | |
4382 | blocks_split++; | |
4383 | } | |
4384 | ||
4385 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
4386 | } | |
4387 | ||
4388 | if (insn == BB_HEAD (bb)) | |
4389 | break; | |
4390 | } | |
4391 | } | |
4392 | ||
4393 | if (blocks_split) | |
4394 | verify_flow_info (); | |
4395 | ||
4396 | return blocks_split; | |
4397 | } | |
4398 | ||
1cb7dfc3 | 4399 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 4400 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
4401 | there is no need to handle this here the loop versioning code handles |
4402 | this. the reason for SECON_HEAD is that it is needed for condition | |
4403 | in trees, and this should be of the same type since it is a hook. */ | |
4404 | static void | |
4405 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
4406 | basic_block second_head ATTRIBUTE_UNUSED, |
4407 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 MH |
4408 | { |
4409 | rtx label, seq, jump; | |
4410 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
4411 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
4412 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
4413 | enum machine_mode mode; | |
4414 | ||
4415 | ||
4416 | label = block_label (first_head); | |
4417 | mode = GET_MODE (op0); | |
4418 | if (mode == VOIDmode) | |
4419 | mode = GET_MODE (op1); | |
4420 | ||
4421 | start_sequence (); | |
4422 | op0 = force_operand (op0, NULL_RTX); | |
4423 | op1 = force_operand (op1, NULL_RTX); | |
4424 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
40e90eac | 4425 | mode, NULL_RTX, NULL_RTX, label, -1); |
1cb7dfc3 MH |
4426 | jump = get_last_insn (); |
4427 | JUMP_LABEL (jump) = label; | |
4428 | LABEL_NUSES (label)++; | |
4429 | seq = get_insns (); | |
4430 | end_sequence (); | |
4431 | ||
4432 | /* Add the new cond , in the new head. */ | |
4433 | emit_insn_after(seq, BB_END(cond_bb)); | |
4434 | } | |
4435 | ||
4436 | ||
4437 | /* Given a block B with unconditional branch at its end, get the | |
4438 | store the return the branch edge and the fall-thru edge in | |
4439 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
4440 | static void | |
4441 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
4442 | edge *fallthru_edge) | |
4443 | { | |
4444 | edge e = EDGE_SUCC (b, 0); | |
4445 | ||
4446 | if (e->flags & EDGE_FALLTHRU) | |
4447 | { | |
4448 | *fallthru_edge = e; | |
4449 | *branch_edge = EDGE_SUCC (b, 1); | |
4450 | } | |
4451 | else | |
4452 | { | |
4453 | *branch_edge = e; | |
4454 | *fallthru_edge = EDGE_SUCC (b, 1); | |
4455 | } | |
4456 | } | |
4457 | ||
5e2d947c JH |
4458 | void |
4459 | init_rtl_bb_info (basic_block bb) | |
4460 | { | |
bcc708fc MM |
4461 | gcc_assert (!bb->il.x.rtl); |
4462 | bb->il.x.head_ = NULL; | |
4463 | bb->il.x.rtl = ggc_alloc_cleared_rtl_bb_info (); | |
5e2d947c JH |
4464 | } |
4465 | ||
14fa2cc0 ZD |
4466 | /* Returns true if it is possible to remove edge E by redirecting |
4467 | it to the destination of the other edge from E->src. */ | |
4468 | ||
4469 | static bool | |
9678086d | 4470 | rtl_can_remove_branch_p (const_edge e) |
14fa2cc0 | 4471 | { |
9678086d KG |
4472 | const_basic_block src = e->src; |
4473 | const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest; | |
4474 | const_rtx insn = BB_END (src), set; | |
14fa2cc0 ZD |
4475 | |
4476 | /* The conditions are taken from try_redirect_by_replacing_jump. */ | |
4477 | if (target == EXIT_BLOCK_PTR) | |
4478 | return false; | |
4479 | ||
4480 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
4481 | return false; | |
4482 | ||
4483 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) | |
4484 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
4485 | return false; | |
4486 | ||
4487 | if (!onlyjump_p (insn) | |
4488 | || tablejump_p (insn, NULL, NULL)) | |
4489 | return false; | |
4490 | ||
4491 | set = single_set (insn); | |
4492 | if (!set || side_effects_p (set)) | |
4493 | return false; | |
4494 | ||
4495 | return true; | |
4496 | } | |
4497 | ||
ffe14686 AM |
4498 | static basic_block |
4499 | rtl_duplicate_bb (basic_block bb) | |
4500 | { | |
4501 | bb = cfg_layout_duplicate_bb (bb); | |
4502 | bb->aux = NULL; | |
4503 | return bb; | |
4504 | } | |
4505 | ||
aa4723d7 SB |
4506 | /* Do book-keeping of basic block BB for the profile consistency checker. |
4507 | If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1 | |
4508 | then do post-pass accounting. Store the counting in RECORD. */ | |
4509 | static void | |
4510 | rtl_account_profile_record (basic_block bb, int after_pass, | |
4511 | struct profile_record *record) | |
4512 | { | |
4513 | rtx insn; | |
4514 | FOR_BB_INSNS (bb, insn) | |
4515 | if (INSN_P (insn)) | |
4516 | { | |
4517 | record->size[after_pass] | |
4518 | += insn_rtx_cost (PATTERN (insn), false); | |
4519 | if (profile_status == PROFILE_READ) | |
4520 | record->time[after_pass] | |
4521 | += insn_rtx_cost (PATTERN (insn), true) * bb->count; | |
4522 | else if (profile_status == PROFILE_GUESSED) | |
4523 | record->time[after_pass] | |
4524 | += insn_rtx_cost (PATTERN (insn), true) * bb->frequency; | |
4525 | } | |
4526 | } | |
4527 | ||
9ee634e3 JH |
4528 | /* Implementation of CFG manipulation for linearized RTL. */ |
4529 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 4530 | "rtl", |
9ee634e3 | 4531 | rtl_verify_flow_info, |
10e9fecc | 4532 | rtl_dump_bb, |
2c895bd1 | 4533 | rtl_dump_bb_for_graph, |
bc35512f | 4534 | rtl_create_basic_block, |
9ee634e3 JH |
4535 | rtl_redirect_edge_and_branch, |
4536 | rtl_redirect_edge_and_branch_force, | |
14fa2cc0 | 4537 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4538 | rtl_delete_block, |
4539 | rtl_split_block, | |
f470c378 | 4540 | rtl_move_block_after, |
bc35512f JH |
4541 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
4542 | rtl_merge_blocks, | |
6de9cd9a DN |
4543 | rtl_predict_edge, |
4544 | rtl_predicted_by_p, | |
ffe14686 AM |
4545 | cfg_layout_can_duplicate_bb_p, |
4546 | rtl_duplicate_bb, | |
f470c378 ZD |
4547 | rtl_split_edge, |
4548 | rtl_make_forwarder_block, | |
6de9cd9a | 4549 | rtl_tidy_fallthru_edge, |
cf103ca4 | 4550 | rtl_force_nonfallthru, |
6de9cd9a DN |
4551 | rtl_block_ends_with_call_p, |
4552 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4553 | rtl_flow_call_edges_add, |
4554 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4555 | NULL, /* execute_on_shrinking_pred */ |
4556 | NULL, /* duplicate loop for trees */ | |
4557 | NULL, /* lv_add_condition_to_bb */ | |
4558 | NULL, /* lv_adjust_loop_header_phi*/ | |
4559 | NULL, /* extract_cond_bb_edges */ | |
df92c640 SB |
4560 | NULL, /* flush_pending_stmts */ |
4561 | rtl_block_empty_p, /* block_empty_p */ | |
4562 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4563 | rtl_account_profile_record, |
9ee634e3 JH |
4564 | }; |
4565 | ||
4566 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
4567 | basic block connected via fallthru edges does not have to be adjacent. | |
4568 | This representation will hopefully become the default one in future | |
4569 | version of the compiler. */ | |
6de9cd9a | 4570 | |
9ee634e3 | 4571 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 4572 | "cfglayout mode", |
bc35512f | 4573 | rtl_verify_flow_info_1, |
10e9fecc | 4574 | rtl_dump_bb, |
2c895bd1 | 4575 | rtl_dump_bb_for_graph, |
bc35512f | 4576 | cfg_layout_create_basic_block, |
9ee634e3 JH |
4577 | cfg_layout_redirect_edge_and_branch, |
4578 | cfg_layout_redirect_edge_and_branch_force, | |
14fa2cc0 | 4579 | rtl_can_remove_branch_p, |
9ee634e3 JH |
4580 | cfg_layout_delete_block, |
4581 | cfg_layout_split_block, | |
f470c378 | 4582 | rtl_move_block_after, |
bc35512f JH |
4583 | cfg_layout_can_merge_blocks_p, |
4584 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
4585 | rtl_predict_edge, |
4586 | rtl_predicted_by_p, | |
4587 | cfg_layout_can_duplicate_bb_p, | |
4588 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
4589 | cfg_layout_split_edge, |
4590 | rtl_make_forwarder_block, | |
cf103ca4 EB |
4591 | NULL, /* tidy_fallthru_edge */ |
4592 | rtl_force_nonfallthru, | |
6de9cd9a DN |
4593 | rtl_block_ends_with_call_p, |
4594 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
4595 | rtl_flow_call_edges_add, |
4596 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
4597 | NULL, /* execute_on_shrinking_pred */ |
4598 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
4599 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
4600 | NULL, /* lv_adjust_loop_header_phi*/ | |
4601 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
df92c640 SB |
4602 | NULL, /* flush_pending_stmts */ |
4603 | rtl_block_empty_p, /* block_empty_p */ | |
4604 | rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */ | |
aa4723d7 | 4605 | rtl_account_profile_record, |
9ee634e3 | 4606 | }; |
78bde837 SB |
4607 | |
4608 | #include "gt-cfgrtl.h" |