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ca6c03ca JH |
1 | /* Control flow graph manipulation code for GNU compiler. |
2 | Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, | |
4ab80063 | 3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. |
ca6c03ca JH |
4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 2, or (at your option) any later | |
10 | version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GCC; see the file COPYING. If not, write to the Free | |
366ccddb KC |
19 | Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA |
20 | 02110-1301, USA. */ | |
ca6c03ca | 21 | |
5f0d2358 RK |
22 | /* This file contains low level functions to manipulate the CFG and analyze it |
23 | that are aware of the RTL intermediate language. | |
ca6c03ca JH |
24 | |
25 | Available functionality: | |
bc35512f | 26 | - Basic CFG/RTL manipulation API documented in cfghooks.h |
5f0d2358 | 27 | - CFG-aware instruction chain manipulation |
ca6c03ca | 28 | delete_insn, delete_insn_chain |
bc35512f JH |
29 | - Edge splitting and committing to edges |
30 | insert_insn_on_edge, commit_edge_insertions | |
31 | - CFG updating after insn simplification | |
32 | purge_dead_edges, purge_all_dead_edges | |
33 | ||
34 | Functions not supposed for generic use: | |
5f0d2358 | 35 | - Infrastructure to determine quickly basic block for insn |
ca6c03ca | 36 | compute_bb_for_insn, update_bb_for_insn, set_block_for_insn, |
5f0d2358 | 37 | - Edge redirection with updating and optimizing of insn chain |
bc35512f | 38 | block_label, tidy_fallthru_edge, force_nonfallthru */ |
ca6c03ca JH |
39 | \f |
40 | #include "config.h" | |
41 | #include "system.h" | |
4977bab6 ZW |
42 | #include "coretypes.h" |
43 | #include "tm.h" | |
ca6c03ca JH |
44 | #include "tree.h" |
45 | #include "rtl.h" | |
46 | #include "hard-reg-set.h" | |
47 | #include "basic-block.h" | |
48 | #include "regs.h" | |
49 | #include "flags.h" | |
50 | #include "output.h" | |
51 | #include "function.h" | |
52 | #include "except.h" | |
53 | #include "toplev.h" | |
54 | #include "tm_p.h" | |
55 | #include "obstack.h" | |
0a2ed1f1 | 56 | #include "insn-config.h" |
9ee634e3 | 57 | #include "cfglayout.h" |
ff25ef99 | 58 | #include "expr.h" |
9fb32434 | 59 | #include "target.h" |
1cb7dfc3 | 60 | #include "cfgloop.h" |
5e2d947c | 61 | #include "ggc.h" |
ef330312 | 62 | #include "tree-pass.h" |
ca6c03ca | 63 | |
d329e058 AJ |
64 | static int can_delete_note_p (rtx); |
65 | static int can_delete_label_p (rtx); | |
2ac66157 | 66 | static void commit_one_edge_insertion (edge); |
d329e058 | 67 | static basic_block rtl_split_edge (edge); |
f470c378 | 68 | static bool rtl_move_block_after (basic_block, basic_block); |
d329e058 | 69 | static int rtl_verify_flow_info (void); |
f470c378 | 70 | static basic_block cfg_layout_split_block (basic_block, void *); |
6de9cd9a | 71 | static edge cfg_layout_redirect_edge_and_branch (edge, basic_block); |
d329e058 AJ |
72 | static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block); |
73 | static void cfg_layout_delete_block (basic_block); | |
74 | static void rtl_delete_block (basic_block); | |
75 | static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block); | |
6de9cd9a | 76 | static edge rtl_redirect_edge_and_branch (edge, basic_block); |
f470c378 ZD |
77 | static basic_block rtl_split_block (basic_block, void *); |
78 | static void rtl_dump_bb (basic_block, FILE *, int); | |
d329e058 | 79 | static int rtl_verify_flow_info_1 (void); |
f470c378 | 80 | static void rtl_make_forwarder_block (edge); |
ca6c03ca JH |
81 | \f |
82 | /* Return true if NOTE is not one of the ones that must be kept paired, | |
5f0d2358 | 83 | so that we may simply delete it. */ |
ca6c03ca JH |
84 | |
85 | static int | |
d329e058 | 86 | can_delete_note_p (rtx note) |
ca6c03ca JH |
87 | { |
88 | return (NOTE_LINE_NUMBER (note) == NOTE_INSN_DELETED | |
87c8b4be | 89 | || NOTE_LINE_NUMBER (note) == NOTE_INSN_BASIC_BLOCK); |
ca6c03ca JH |
90 | } |
91 | ||
92 | /* True if a given label can be deleted. */ | |
93 | ||
94 | static int | |
d329e058 | 95 | can_delete_label_p (rtx label) |
ca6c03ca | 96 | { |
5f0d2358 RK |
97 | return (!LABEL_PRESERVE_P (label) |
98 | /* User declared labels must be preserved. */ | |
99 | && LABEL_NAME (label) == 0 | |
610d2478 | 100 | && !in_expr_list_p (forced_labels, label)); |
ca6c03ca JH |
101 | } |
102 | ||
103 | /* Delete INSN by patching it out. Return the next insn. */ | |
104 | ||
105 | rtx | |
d329e058 | 106 | delete_insn (rtx insn) |
ca6c03ca JH |
107 | { |
108 | rtx next = NEXT_INSN (insn); | |
109 | rtx note; | |
110 | bool really_delete = true; | |
111 | ||
4b4bf941 | 112 | if (LABEL_P (insn)) |
ca6c03ca JH |
113 | { |
114 | /* Some labels can't be directly removed from the INSN chain, as they | |
c22cacf3 MS |
115 | might be references via variables, constant pool etc. |
116 | Convert them to the special NOTE_INSN_DELETED_LABEL note. */ | |
ca6c03ca JH |
117 | if (! can_delete_label_p (insn)) |
118 | { | |
119 | const char *name = LABEL_NAME (insn); | |
120 | ||
121 | really_delete = false; | |
122 | PUT_CODE (insn, NOTE); | |
123 | NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED_LABEL; | |
6773e15f | 124 | NOTE_DELETED_LABEL_NAME (insn) = name; |
ca6c03ca | 125 | } |
5f0d2358 | 126 | |
ca6c03ca JH |
127 | remove_node_from_expr_list (insn, &nonlocal_goto_handler_labels); |
128 | } | |
129 | ||
130 | if (really_delete) | |
131 | { | |
cda94cbb | 132 | /* If this insn has already been deleted, something is very wrong. */ |
341c100f | 133 | gcc_assert (!INSN_DELETED_P (insn)); |
ca6c03ca JH |
134 | remove_insn (insn); |
135 | INSN_DELETED_P (insn) = 1; | |
136 | } | |
137 | ||
138 | /* If deleting a jump, decrement the use count of the label. Deleting | |
139 | the label itself should happen in the normal course of block merging. */ | |
4b4bf941 | 140 | if (JUMP_P (insn) |
ca6c03ca | 141 | && JUMP_LABEL (insn) |
4b4bf941 | 142 | && LABEL_P (JUMP_LABEL (insn))) |
ca6c03ca JH |
143 | LABEL_NUSES (JUMP_LABEL (insn))--; |
144 | ||
145 | /* Also if deleting an insn that references a label. */ | |
9295a326 JZ |
146 | else |
147 | { | |
148 | while ((note = find_reg_note (insn, REG_LABEL, NULL_RTX)) != NULL_RTX | |
4b4bf941 | 149 | && LABEL_P (XEXP (note, 0))) |
9295a326 JZ |
150 | { |
151 | LABEL_NUSES (XEXP (note, 0))--; | |
152 | remove_note (insn, note); | |
153 | } | |
154 | } | |
ca6c03ca | 155 | |
4b4bf941 | 156 | if (JUMP_P (insn) |
ca6c03ca JH |
157 | && (GET_CODE (PATTERN (insn)) == ADDR_VEC |
158 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)) | |
159 | { | |
160 | rtx pat = PATTERN (insn); | |
161 | int diff_vec_p = GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC; | |
162 | int len = XVECLEN (pat, diff_vec_p); | |
163 | int i; | |
164 | ||
165 | for (i = 0; i < len; i++) | |
a124fcda RH |
166 | { |
167 | rtx label = XEXP (XVECEXP (pat, diff_vec_p, i), 0); | |
168 | ||
169 | /* When deleting code in bulk (e.g. removing many unreachable | |
170 | blocks) we can delete a label that's a target of the vector | |
171 | before deleting the vector itself. */ | |
4b4bf941 | 172 | if (!NOTE_P (label)) |
a124fcda RH |
173 | LABEL_NUSES (label)--; |
174 | } | |
ca6c03ca JH |
175 | } |
176 | ||
177 | return next; | |
178 | } | |
179 | ||
3dec4024 JH |
180 | /* Like delete_insn but also purge dead edges from BB. */ |
181 | rtx | |
d329e058 | 182 | delete_insn_and_edges (rtx insn) |
3dec4024 JH |
183 | { |
184 | rtx x; | |
185 | bool purge = false; | |
186 | ||
ba4f7968 | 187 | if (INSN_P (insn) |
3dec4024 | 188 | && BLOCK_FOR_INSN (insn) |
a813c111 | 189 | && BB_END (BLOCK_FOR_INSN (insn)) == insn) |
3dec4024 JH |
190 | purge = true; |
191 | x = delete_insn (insn); | |
192 | if (purge) | |
193 | purge_dead_edges (BLOCK_FOR_INSN (insn)); | |
194 | return x; | |
195 | } | |
196 | ||
ca6c03ca JH |
197 | /* Unlink a chain of insns between START and FINISH, leaving notes |
198 | that must be paired. */ | |
199 | ||
200 | void | |
d329e058 | 201 | delete_insn_chain (rtx start, rtx finish) |
ca6c03ca | 202 | { |
ca6c03ca JH |
203 | rtx next; |
204 | ||
5f0d2358 RK |
205 | /* Unchain the insns one by one. It would be quicker to delete all of these |
206 | with a single unchaining, rather than one at a time, but we need to keep | |
207 | the NOTE's. */ | |
ca6c03ca JH |
208 | while (1) |
209 | { | |
210 | next = NEXT_INSN (start); | |
4b4bf941 | 211 | if (NOTE_P (start) && !can_delete_note_p (start)) |
ca6c03ca JH |
212 | ; |
213 | else | |
214 | next = delete_insn (start); | |
215 | ||
216 | if (start == finish) | |
217 | break; | |
218 | start = next; | |
219 | } | |
220 | } | |
3dec4024 JH |
221 | |
222 | /* Like delete_insn but also purge dead edges from BB. */ | |
223 | void | |
d329e058 | 224 | delete_insn_chain_and_edges (rtx first, rtx last) |
3dec4024 JH |
225 | { |
226 | bool purge = false; | |
227 | ||
ba4f7968 | 228 | if (INSN_P (last) |
3dec4024 | 229 | && BLOCK_FOR_INSN (last) |
a813c111 | 230 | && BB_END (BLOCK_FOR_INSN (last)) == last) |
3dec4024 JH |
231 | purge = true; |
232 | delete_insn_chain (first, last); | |
233 | if (purge) | |
234 | purge_dead_edges (BLOCK_FOR_INSN (last)); | |
235 | } | |
ca6c03ca | 236 | \f |
5f0d2358 RK |
237 | /* Create a new basic block consisting of the instructions between HEAD and END |
238 | inclusive. This function is designed to allow fast BB construction - reuses | |
239 | the note and basic block struct in BB_NOTE, if any and do not grow | |
240 | BASIC_BLOCK chain and should be used directly only by CFG construction code. | |
241 | END can be NULL in to create new empty basic block before HEAD. Both END | |
918ed612 ZD |
242 | and HEAD can be NULL to create basic block at the end of INSN chain. |
243 | AFTER is the basic block we should be put after. */ | |
ca6c03ca JH |
244 | |
245 | basic_block | |
d329e058 | 246 | create_basic_block_structure (rtx head, rtx end, rtx bb_note, basic_block after) |
ca6c03ca JH |
247 | { |
248 | basic_block bb; | |
249 | ||
250 | if (bb_note | |
ca6c03ca JH |
251 | && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL |
252 | && bb->aux == NULL) | |
253 | { | |
254 | /* If we found an existing note, thread it back onto the chain. */ | |
255 | ||
256 | rtx after; | |
257 | ||
4b4bf941 | 258 | if (LABEL_P (head)) |
ca6c03ca JH |
259 | after = head; |
260 | else | |
261 | { | |
262 | after = PREV_INSN (head); | |
263 | head = bb_note; | |
264 | } | |
265 | ||
266 | if (after != bb_note && NEXT_INSN (after) != bb_note) | |
ba4f7968 | 267 | reorder_insns_nobb (bb_note, bb_note, after); |
ca6c03ca JH |
268 | } |
269 | else | |
270 | { | |
271 | /* Otherwise we must create a note and a basic block structure. */ | |
272 | ||
273 | bb = alloc_block (); | |
274 | ||
5e2d947c | 275 | init_rtl_bb_info (bb); |
ca6c03ca | 276 | if (!head && !end) |
5f0d2358 RK |
277 | head = end = bb_note |
278 | = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ()); | |
4b4bf941 | 279 | else if (LABEL_P (head) && end) |
ca6c03ca JH |
280 | { |
281 | bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head); | |
282 | if (head == end) | |
283 | end = bb_note; | |
284 | } | |
285 | else | |
286 | { | |
287 | bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head); | |
288 | head = bb_note; | |
289 | if (!end) | |
290 | end = head; | |
291 | } | |
5f0d2358 | 292 | |
ca6c03ca JH |
293 | NOTE_BASIC_BLOCK (bb_note) = bb; |
294 | } | |
295 | ||
296 | /* Always include the bb note in the block. */ | |
297 | if (NEXT_INSN (end) == bb_note) | |
298 | end = bb_note; | |
299 | ||
a813c111 SB |
300 | BB_HEAD (bb) = head; |
301 | BB_END (bb) = end; | |
852c6ec7 | 302 | bb->index = last_basic_block++; |
5e2d947c | 303 | bb->flags = BB_NEW | BB_RTL; |
918ed612 | 304 | link_block (bb, after); |
68f9b844 | 305 | SET_BASIC_BLOCK (bb->index, bb); |
ba4f7968 | 306 | update_bb_for_insn (bb); |
076c7ab8 | 307 | BB_SET_PARTITION (bb, BB_UNPARTITIONED); |
ca6c03ca JH |
308 | |
309 | /* Tag the block so that we know it has been used when considering | |
310 | other basic block notes. */ | |
311 | bb->aux = bb; | |
312 | ||
313 | return bb; | |
314 | } | |
315 | ||
5f0d2358 | 316 | /* Create new basic block consisting of instructions in between HEAD and END |
918ed612 | 317 | and place it to the BB chain after block AFTER. END can be NULL in to |
5f0d2358 RK |
318 | create new empty basic block before HEAD. Both END and HEAD can be NULL to |
319 | create basic block at the end of INSN chain. */ | |
ca6c03ca | 320 | |
bc35512f JH |
321 | static basic_block |
322 | rtl_create_basic_block (void *headp, void *endp, basic_block after) | |
ca6c03ca | 323 | { |
bc35512f | 324 | rtx head = headp, end = endp; |
ca6c03ca | 325 | basic_block bb; |
0b17ab2f | 326 | |
7eca0767 | 327 | /* Grow the basic block array if needed. */ |
68f9b844 | 328 | if ((size_t) last_basic_block >= VEC_length (basic_block, basic_block_info)) |
7eca0767 JH |
329 | { |
330 | size_t new_size = last_basic_block + (last_basic_block + 3) / 4; | |
a590ac65 | 331 | VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size); |
7eca0767 | 332 | } |
0b17ab2f | 333 | |
bf77398c | 334 | n_basic_blocks++; |
ca6c03ca | 335 | |
852c6ec7 | 336 | bb = create_basic_block_structure (head, end, NULL, after); |
ca6c03ca JH |
337 | bb->aux = NULL; |
338 | return bb; | |
339 | } | |
bc35512f JH |
340 | |
341 | static basic_block | |
342 | cfg_layout_create_basic_block (void *head, void *end, basic_block after) | |
343 | { | |
344 | basic_block newbb = rtl_create_basic_block (head, end, after); | |
345 | ||
bc35512f JH |
346 | return newbb; |
347 | } | |
ca6c03ca JH |
348 | \f |
349 | /* Delete the insns in a (non-live) block. We physically delete every | |
350 | non-deleted-note insn, and update the flow graph appropriately. | |
351 | ||
352 | Return nonzero if we deleted an exception handler. */ | |
353 | ||
354 | /* ??? Preserving all such notes strikes me as wrong. It would be nice | |
355 | to post-process the stream to remove empty blocks, loops, ranges, etc. */ | |
356 | ||
f0fda11c | 357 | static void |
d329e058 | 358 | rtl_delete_block (basic_block b) |
ca6c03ca | 359 | { |
96370780 | 360 | rtx insn, end; |
ca6c03ca JH |
361 | |
362 | /* If the head of this block is a CODE_LABEL, then it might be the | |
f39e46ba SB |
363 | label for an exception handler which can't be reached. We need |
364 | to remove the label from the exception_handler_label list. */ | |
a813c111 | 365 | insn = BB_HEAD (b); |
4b4bf941 | 366 | if (LABEL_P (insn)) |
ca6c03ca JH |
367 | maybe_remove_eh_handler (insn); |
368 | ||
96370780 | 369 | end = get_last_bb_insn (b); |
ca6c03ca JH |
370 | |
371 | /* Selectively delete the entire chain. */ | |
a813c111 | 372 | BB_HEAD (b) = NULL; |
ca6c03ca | 373 | delete_insn_chain (insn, end); |
370adb7b JH |
374 | if (b->il.rtl->global_live_at_start) |
375 | { | |
376 | FREE_REG_SET (b->il.rtl->global_live_at_start); | |
377 | FREE_REG_SET (b->il.rtl->global_live_at_end); | |
378 | b->il.rtl->global_live_at_start = NULL; | |
379 | b->il.rtl->global_live_at_end = NULL; | |
380 | } | |
ca6c03ca JH |
381 | } |
382 | \f | |
852c6ec7 | 383 | /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */ |
ca6c03ca JH |
384 | |
385 | void | |
d329e058 | 386 | compute_bb_for_insn (void) |
ca6c03ca | 387 | { |
e0082a72 | 388 | basic_block bb; |
ca6c03ca | 389 | |
e0082a72 | 390 | FOR_EACH_BB (bb) |
ca6c03ca | 391 | { |
a813c111 | 392 | rtx end = BB_END (bb); |
5f0d2358 | 393 | rtx insn; |
ca6c03ca | 394 | |
a813c111 | 395 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 396 | { |
ba4f7968 | 397 | BLOCK_FOR_INSN (insn) = bb; |
ca6c03ca JH |
398 | if (insn == end) |
399 | break; | |
ca6c03ca JH |
400 | } |
401 | } | |
402 | } | |
403 | ||
404 | /* Release the basic_block_for_insn array. */ | |
405 | ||
c2924966 | 406 | unsigned int |
d329e058 | 407 | free_bb_for_insn (void) |
ca6c03ca | 408 | { |
ba4f7968 JH |
409 | rtx insn; |
410 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) | |
4b4bf941 | 411 | if (!BARRIER_P (insn)) |
ba4f7968 | 412 | BLOCK_FOR_INSN (insn) = NULL; |
c2924966 | 413 | return 0; |
ca6c03ca JH |
414 | } |
415 | ||
ef330312 PB |
416 | struct tree_opt_pass pass_free_cfg = |
417 | { | |
418 | NULL, /* name */ | |
419 | NULL, /* gate */ | |
420 | free_bb_for_insn, /* execute */ | |
421 | NULL, /* sub */ | |
422 | NULL, /* next */ | |
423 | 0, /* static_pass_number */ | |
424 | 0, /* tv_id */ | |
425 | 0, /* properties_required */ | |
426 | 0, /* properties_provided */ | |
427 | PROP_cfg, /* properties_destroyed */ | |
428 | 0, /* todo_flags_start */ | |
429 | 0, /* todo_flags_finish */ | |
430 | 0 /* letter */ | |
431 | }; | |
432 | ||
91278841 AP |
433 | /* Return RTX to emit after when we want to emit code on the entry of function. */ |
434 | rtx | |
435 | entry_of_function (void) | |
436 | { | |
c22cacf3 | 437 | return (n_basic_blocks > NUM_FIXED_BLOCKS ? |
24bd1a0b | 438 | BB_HEAD (ENTRY_BLOCK_PTR->next_bb) : get_insns ()); |
91278841 AP |
439 | } |
440 | ||
11b904a1 BS |
441 | /* Emit INSN at the entry point of the function, ensuring that it is only |
442 | executed once per function. */ | |
443 | void | |
444 | emit_insn_at_entry (rtx insn) | |
445 | { | |
446 | edge_iterator ei = ei_start (ENTRY_BLOCK_PTR->succs); | |
447 | edge e = ei_safe_edge (ei); | |
5419bc7f | 448 | gcc_assert (e->flags & EDGE_FALLTHRU); |
11b904a1 BS |
449 | |
450 | insert_insn_on_edge (insn, e); | |
451 | commit_edge_insertions (); | |
452 | } | |
453 | ||
ca6c03ca JH |
454 | /* Update insns block within BB. */ |
455 | ||
456 | void | |
d329e058 | 457 | update_bb_for_insn (basic_block bb) |
ca6c03ca JH |
458 | { |
459 | rtx insn; | |
460 | ||
a813c111 | 461 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
ca6c03ca | 462 | { |
4b4bf941 | 463 | if (!BARRIER_P (insn)) |
bcc53e2a | 464 | set_block_for_insn (insn, bb); |
a813c111 | 465 | if (insn == BB_END (bb)) |
ca6c03ca JH |
466 | break; |
467 | } | |
468 | } | |
ca6c03ca | 469 | \f |
f470c378 ZD |
470 | /* Creates a new basic block just after basic block B by splitting |
471 | everything after specified instruction I. */ | |
ca6c03ca | 472 | |
f470c378 | 473 | static basic_block |
d329e058 | 474 | rtl_split_block (basic_block bb, void *insnp) |
ca6c03ca JH |
475 | { |
476 | basic_block new_bb; | |
9ee634e3 | 477 | rtx insn = insnp; |
f470c378 | 478 | edge e; |
628f6a4e | 479 | edge_iterator ei; |
ca6c03ca | 480 | |
f470c378 ZD |
481 | if (!insn) |
482 | { | |
483 | insn = first_insn_after_basic_block_note (bb); | |
484 | ||
485 | if (insn) | |
486 | insn = PREV_INSN (insn); | |
487 | else | |
488 | insn = get_last_insn (); | |
489 | } | |
490 | ||
491 | /* We probably should check type of the insn so that we do not create | |
492 | inconsistent cfg. It is checked in verify_flow_info anyway, so do not | |
493 | bother. */ | |
494 | if (insn == BB_END (bb)) | |
495 | emit_note_after (NOTE_INSN_DELETED, insn); | |
ca6c03ca JH |
496 | |
497 | /* Create the new basic block. */ | |
a813c111 | 498 | new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb); |
076c7ab8 | 499 | BB_COPY_PARTITION (new_bb, bb); |
a813c111 | 500 | BB_END (bb) = insn; |
ca6c03ca JH |
501 | |
502 | /* Redirect the outgoing edges. */ | |
628f6a4e BE |
503 | new_bb->succs = bb->succs; |
504 | bb->succs = NULL; | |
505 | FOR_EACH_EDGE (e, ei, new_bb->succs) | |
ca6c03ca JH |
506 | e->src = new_bb; |
507 | ||
5e2d947c | 508 | if (bb->il.rtl->global_live_at_start) |
ca6c03ca | 509 | { |
5e2d947c JH |
510 | new_bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack); |
511 | new_bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack); | |
512 | COPY_REG_SET (new_bb->il.rtl->global_live_at_end, bb->il.rtl->global_live_at_end); | |
ca6c03ca JH |
513 | |
514 | /* We now have to calculate which registers are live at the end | |
515 | of the split basic block and at the start of the new basic | |
516 | block. Start with those registers that are known to be live | |
517 | at the end of the original basic block and get | |
518 | propagate_block to determine which registers are live. */ | |
5e2d947c JH |
519 | COPY_REG_SET (new_bb->il.rtl->global_live_at_start, bb->il.rtl->global_live_at_end); |
520 | propagate_block (new_bb, new_bb->il.rtl->global_live_at_start, NULL, NULL, 0); | |
521 | COPY_REG_SET (bb->il.rtl->global_live_at_end, | |
522 | new_bb->il.rtl->global_live_at_start); | |
0a2ed1f1 JH |
523 | #ifdef HAVE_conditional_execution |
524 | /* In the presence of conditional execution we are not able to update | |
525 | liveness precisely. */ | |
526 | if (reload_completed) | |
527 | { | |
528 | bb->flags |= BB_DIRTY; | |
529 | new_bb->flags |= BB_DIRTY; | |
530 | } | |
531 | #endif | |
ca6c03ca JH |
532 | } |
533 | ||
f470c378 | 534 | return new_bb; |
bc35512f JH |
535 | } |
536 | ||
ca6c03ca | 537 | /* Blocks A and B are to be merged into a single block A. The insns |
bc35512f | 538 | are already contiguous. */ |
ca6c03ca | 539 | |
bc35512f JH |
540 | static void |
541 | rtl_merge_blocks (basic_block a, basic_block b) | |
ca6c03ca | 542 | { |
a813c111 | 543 | rtx b_head = BB_HEAD (b), b_end = BB_END (b), a_end = BB_END (a); |
ca6c03ca JH |
544 | rtx del_first = NULL_RTX, del_last = NULL_RTX; |
545 | int b_empty = 0; | |
546 | ||
547 | /* If there was a CODE_LABEL beginning B, delete it. */ | |
4b4bf941 | 548 | if (LABEL_P (b_head)) |
ca6c03ca | 549 | { |
2c97f8e4 RH |
550 | /* This might have been an EH label that no longer has incoming |
551 | EH edges. Update data structures to match. */ | |
552 | maybe_remove_eh_handler (b_head); | |
c22cacf3 | 553 | |
ca6c03ca JH |
554 | /* Detect basic blocks with nothing but a label. This can happen |
555 | in particular at the end of a function. */ | |
556 | if (b_head == b_end) | |
557 | b_empty = 1; | |
5f0d2358 | 558 | |
ca6c03ca JH |
559 | del_first = del_last = b_head; |
560 | b_head = NEXT_INSN (b_head); | |
561 | } | |
562 | ||
5f0d2358 RK |
563 | /* Delete the basic block note and handle blocks containing just that |
564 | note. */ | |
ca6c03ca JH |
565 | if (NOTE_INSN_BASIC_BLOCK_P (b_head)) |
566 | { | |
567 | if (b_head == b_end) | |
568 | b_empty = 1; | |
569 | if (! del_last) | |
570 | del_first = b_head; | |
5f0d2358 | 571 | |
ca6c03ca JH |
572 | del_last = b_head; |
573 | b_head = NEXT_INSN (b_head); | |
574 | } | |
575 | ||
576 | /* If there was a jump out of A, delete it. */ | |
4b4bf941 | 577 | if (JUMP_P (a_end)) |
ca6c03ca JH |
578 | { |
579 | rtx prev; | |
580 | ||
581 | for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev)) | |
4b4bf941 | 582 | if (!NOTE_P (prev) |
ca6c03ca | 583 | || NOTE_LINE_NUMBER (prev) == NOTE_INSN_BASIC_BLOCK |
a813c111 | 584 | || prev == BB_HEAD (a)) |
ca6c03ca JH |
585 | break; |
586 | ||
587 | del_first = a_end; | |
588 | ||
589 | #ifdef HAVE_cc0 | |
590 | /* If this was a conditional jump, we need to also delete | |
591 | the insn that set cc0. */ | |
592 | if (only_sets_cc0_p (prev)) | |
593 | { | |
594 | rtx tmp = prev; | |
5f0d2358 | 595 | |
ca6c03ca JH |
596 | prev = prev_nonnote_insn (prev); |
597 | if (!prev) | |
a813c111 | 598 | prev = BB_HEAD (a); |
ca6c03ca JH |
599 | del_first = tmp; |
600 | } | |
601 | #endif | |
602 | ||
603 | a_end = PREV_INSN (del_first); | |
604 | } | |
4b4bf941 | 605 | else if (BARRIER_P (NEXT_INSN (a_end))) |
ca6c03ca JH |
606 | del_first = NEXT_INSN (a_end); |
607 | ||
ca6c03ca JH |
608 | /* Delete everything marked above as well as crap that might be |
609 | hanging out between the two blocks. */ | |
f470c378 | 610 | BB_HEAD (b) = NULL; |
ca6c03ca JH |
611 | delete_insn_chain (del_first, del_last); |
612 | ||
613 | /* Reassociate the insns of B with A. */ | |
614 | if (!b_empty) | |
615 | { | |
ba4f7968 | 616 | rtx x; |
5f0d2358 | 617 | |
ba4f7968 JH |
618 | for (x = a_end; x != b_end; x = NEXT_INSN (x)) |
619 | set_block_for_insn (x, a); | |
5f0d2358 | 620 | |
ba4f7968 | 621 | set_block_for_insn (b_end, a); |
5f0d2358 | 622 | |
ca6c03ca JH |
623 | a_end = b_end; |
624 | } | |
5f0d2358 | 625 | |
a813c111 | 626 | BB_END (a) = a_end; |
5e2d947c | 627 | a->il.rtl->global_live_at_end = b->il.rtl->global_live_at_end; |
ca6c03ca | 628 | } |
bc35512f JH |
629 | |
630 | /* Return true when block A and B can be merged. */ | |
631 | static bool | |
632 | rtl_can_merge_blocks (basic_block a,basic_block b) | |
633 | { | |
750054a2 CT |
634 | /* If we are partitioning hot/cold basic blocks, we don't want to |
635 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
636 | and cold sections. |
637 | ||
8e8d5162 | 638 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
639 | be optimizable (or blocks that appear to be mergeable), but which really |
640 | must be left untouched (they are required to make it safely across | |
641 | partition boundaries). See the comments at the top of | |
8e8d5162 | 642 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
076c7ab8 | 643 | |
87c8b4be | 644 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 645 | return false; |
750054a2 | 646 | |
bc35512f | 647 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
648 | return (single_succ_p (a) |
649 | && single_succ (a) == b | |
650 | && single_pred_p (b) | |
628f6a4e | 651 | && a != b |
bc35512f | 652 | /* Must be simple edge. */ |
c5cbcccf | 653 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f JH |
654 | && a->next_bb == b |
655 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR | |
656 | /* If the jump insn has side effects, | |
657 | we can't kill the edge. */ | |
4b4bf941 | 658 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 659 | || (reload_completed |
a813c111 | 660 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f | 661 | } |
ca6c03ca | 662 | \f |
5f0d2358 RK |
663 | /* Return the label in the head of basic block BLOCK. Create one if it doesn't |
664 | exist. */ | |
ca6c03ca JH |
665 | |
666 | rtx | |
d329e058 | 667 | block_label (basic_block block) |
ca6c03ca JH |
668 | { |
669 | if (block == EXIT_BLOCK_PTR) | |
670 | return NULL_RTX; | |
5f0d2358 | 671 | |
4b4bf941 | 672 | if (!LABEL_P (BB_HEAD (block))) |
ca6c03ca | 673 | { |
a813c111 | 674 | BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block)); |
ca6c03ca | 675 | } |
5f0d2358 | 676 | |
a813c111 | 677 | return BB_HEAD (block); |
ca6c03ca JH |
678 | } |
679 | ||
680 | /* Attempt to perform edge redirection by replacing possibly complex jump | |
5f0d2358 RK |
681 | instruction by unconditional jump or removing jump completely. This can |
682 | apply only if all edges now point to the same block. The parameters and | |
683 | return values are equivalent to redirect_edge_and_branch. */ | |
ca6c03ca | 684 | |
6de9cd9a | 685 | edge |
bc35512f | 686 | try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout) |
ca6c03ca JH |
687 | { |
688 | basic_block src = e->src; | |
a813c111 | 689 | rtx insn = BB_END (src), kill_from; |
e1233a7d | 690 | rtx set; |
ca6c03ca | 691 | int fallthru = 0; |
750054a2 CT |
692 | |
693 | /* If we are partitioning hot/cold basic blocks, we don't want to | |
694 | mess up unconditional or indirect jumps that cross between hot | |
8e8d5162 CT |
695 | and cold sections. |
696 | ||
697 | Basic block partitioning may result in some jumps that appear to | |
c22cacf3 MS |
698 | be optimizable (or blocks that appear to be mergeable), but which really |
699 | must be left untouched (they are required to make it safely across | |
700 | partition boundaries). See the comments at the top of | |
8e8d5162 | 701 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
c22cacf3 | 702 | |
87c8b4be CT |
703 | if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX) |
704 | || BB_PARTITION (src) != BB_PARTITION (target)) | |
9cf84a3c | 705 | return NULL; |
750054a2 | 706 | |
6a66a8a7 KH |
707 | /* We can replace or remove a complex jump only when we have exactly |
708 | two edges. Also, if we have exactly one outgoing edge, we can | |
709 | redirect that. */ | |
710 | if (EDGE_COUNT (src->succs) >= 3 | |
711 | /* Verify that all targets will be TARGET. Specifically, the | |
712 | edge that is not E must also go to TARGET. */ | |
713 | || (EDGE_COUNT (src->succs) == 2 | |
714 | && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)) | |
715 | return NULL; | |
5f0d2358 | 716 | |
6a66a8a7 | 717 | if (!onlyjump_p (insn)) |
6de9cd9a | 718 | return NULL; |
3348b696 | 719 | if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL)) |
6de9cd9a | 720 | return NULL; |
ca6c03ca JH |
721 | |
722 | /* Avoid removing branch with side effects. */ | |
723 | set = single_set (insn); | |
724 | if (!set || side_effects_p (set)) | |
6de9cd9a | 725 | return NULL; |
ca6c03ca JH |
726 | |
727 | /* In case we zap a conditional jump, we'll need to kill | |
728 | the cc0 setter too. */ | |
729 | kill_from = insn; | |
730 | #ifdef HAVE_cc0 | |
9caea4a7 RS |
731 | if (reg_mentioned_p (cc0_rtx, PATTERN (insn)) |
732 | && only_sets_cc0_p (PREV_INSN (insn))) | |
ca6c03ca JH |
733 | kill_from = PREV_INSN (insn); |
734 | #endif | |
735 | ||
736 | /* See if we can create the fallthru edge. */ | |
bc35512f | 737 | if (in_cfglayout || can_fallthru (src, target)) |
ca6c03ca | 738 | { |
c263766c RH |
739 | if (dump_file) |
740 | fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn)); | |
ca6c03ca JH |
741 | fallthru = 1; |
742 | ||
eaec9b3d | 743 | /* Selectively unlink whole insn chain. */ |
bc35512f JH |
744 | if (in_cfglayout) |
745 | { | |
370369e1 | 746 | rtx insn = src->il.rtl->footer; |
bc35512f | 747 | |
c22cacf3 | 748 | delete_insn_chain (kill_from, BB_END (src)); |
bc35512f JH |
749 | |
750 | /* Remove barriers but keep jumptables. */ | |
751 | while (insn) | |
752 | { | |
4b4bf941 | 753 | if (BARRIER_P (insn)) |
bc35512f JH |
754 | { |
755 | if (PREV_INSN (insn)) | |
756 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
757 | else | |
370369e1 | 758 | src->il.rtl->footer = NEXT_INSN (insn); |
bc35512f JH |
759 | if (NEXT_INSN (insn)) |
760 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
761 | } | |
4b4bf941 | 762 | if (LABEL_P (insn)) |
bc35512f JH |
763 | break; |
764 | insn = NEXT_INSN (insn); | |
765 | } | |
766 | } | |
767 | else | |
c22cacf3 | 768 | delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target))); |
ca6c03ca | 769 | } |
5f0d2358 | 770 | |
ca6c03ca JH |
771 | /* If this already is simplejump, redirect it. */ |
772 | else if (simplejump_p (insn)) | |
773 | { | |
774 | if (e->dest == target) | |
6de9cd9a | 775 | return NULL; |
c263766c RH |
776 | if (dump_file) |
777 | fprintf (dump_file, "Redirecting jump %i from %i to %i.\n", | |
0b17ab2f | 778 | INSN_UID (insn), e->dest->index, target->index); |
6ee3c8e4 JJ |
779 | if (!redirect_jump (insn, block_label (target), 0)) |
780 | { | |
341c100f NS |
781 | gcc_assert (target == EXIT_BLOCK_PTR); |
782 | return NULL; | |
6ee3c8e4 | 783 | } |
ca6c03ca | 784 | } |
5f0d2358 | 785 | |
6ee3c8e4 JJ |
786 | /* Cannot do anything for target exit block. */ |
787 | else if (target == EXIT_BLOCK_PTR) | |
6de9cd9a | 788 | return NULL; |
6ee3c8e4 | 789 | |
ca6c03ca JH |
790 | /* Or replace possibly complicated jump insn by simple jump insn. */ |
791 | else | |
792 | { | |
793 | rtx target_label = block_label (target); | |
eb5b8ad4 | 794 | rtx barrier, label, table; |
ca6c03ca | 795 | |
a7102479 | 796 | emit_jump_insn_after_noloc (gen_jump (target_label), insn); |
a813c111 | 797 | JUMP_LABEL (BB_END (src)) = target_label; |
ca6c03ca | 798 | LABEL_NUSES (target_label)++; |
c263766c RH |
799 | if (dump_file) |
800 | fprintf (dump_file, "Replacing insn %i by jump %i\n", | |
a813c111 | 801 | INSN_UID (insn), INSN_UID (BB_END (src))); |
ca6c03ca | 802 | |
4da2eb6b | 803 | |
ca6c03ca JH |
804 | delete_insn_chain (kill_from, insn); |
805 | ||
4da2eb6b RH |
806 | /* Recognize a tablejump that we are converting to a |
807 | simple jump and remove its associated CODE_LABEL | |
808 | and ADDR_VEC or ADDR_DIFF_VEC. */ | |
3348b696 | 809 | if (tablejump_p (insn, &label, &table)) |
4da2eb6b | 810 | delete_insn_chain (label, table); |
eb5b8ad4 | 811 | |
a813c111 | 812 | barrier = next_nonnote_insn (BB_END (src)); |
4b4bf941 | 813 | if (!barrier || !BARRIER_P (barrier)) |
a813c111 | 814 | emit_barrier_after (BB_END (src)); |
5d693491 JZ |
815 | else |
816 | { | |
a813c111 | 817 | if (barrier != NEXT_INSN (BB_END (src))) |
5d693491 JZ |
818 | { |
819 | /* Move the jump before barrier so that the notes | |
820 | which originally were or were created before jump table are | |
821 | inside the basic block. */ | |
a813c111 | 822 | rtx new_insn = BB_END (src); |
5d693491 JZ |
823 | rtx tmp; |
824 | ||
a813c111 | 825 | for (tmp = NEXT_INSN (BB_END (src)); tmp != barrier; |
5d693491 JZ |
826 | tmp = NEXT_INSN (tmp)) |
827 | set_block_for_insn (tmp, src); | |
828 | ||
829 | NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn); | |
830 | PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn); | |
831 | ||
832 | NEXT_INSN (new_insn) = barrier; | |
833 | NEXT_INSN (PREV_INSN (barrier)) = new_insn; | |
834 | ||
835 | PREV_INSN (new_insn) = PREV_INSN (barrier); | |
836 | PREV_INSN (barrier) = new_insn; | |
837 | } | |
838 | } | |
ca6c03ca JH |
839 | } |
840 | ||
841 | /* Keep only one edge out and set proper flags. */ | |
c5cbcccf | 842 | if (!single_succ_p (src)) |
628f6a4e | 843 | remove_edge (e); |
c5cbcccf | 844 | gcc_assert (single_succ_p (src)); |
628f6a4e | 845 | |
c5cbcccf | 846 | e = single_succ_edge (src); |
ca6c03ca JH |
847 | if (fallthru) |
848 | e->flags = EDGE_FALLTHRU; | |
849 | else | |
850 | e->flags = 0; | |
5f0d2358 | 851 | |
ca6c03ca JH |
852 | e->probability = REG_BR_PROB_BASE; |
853 | e->count = src->count; | |
854 | ||
ca6c03ca JH |
855 | if (e->dest != target) |
856 | redirect_edge_succ (e, target); | |
5f0d2358 | 857 | |
6de9cd9a | 858 | return e; |
ca6c03ca JH |
859 | } |
860 | ||
6de9cd9a DN |
861 | /* Redirect edge representing branch of (un)conditional jump or tablejump, |
862 | NULL on failure */ | |
863 | static edge | |
bc35512f | 864 | redirect_branch_edge (edge e, basic_block target) |
ca6c03ca JH |
865 | { |
866 | rtx tmp; | |
a813c111 | 867 | rtx old_label = BB_HEAD (e->dest); |
ca6c03ca | 868 | basic_block src = e->src; |
a813c111 | 869 | rtx insn = BB_END (src); |
ca6c03ca | 870 | |
ca6c03ca JH |
871 | /* We can only redirect non-fallthru edges of jump insn. */ |
872 | if (e->flags & EDGE_FALLTHRU) | |
6de9cd9a | 873 | return NULL; |
4b4bf941 | 874 | else if (!JUMP_P (insn)) |
6de9cd9a | 875 | return NULL; |
ca6c03ca JH |
876 | |
877 | /* Recognize a tablejump and adjust all matching cases. */ | |
e1233a7d | 878 | if (tablejump_p (insn, NULL, &tmp)) |
ca6c03ca JH |
879 | { |
880 | rtvec vec; | |
881 | int j; | |
882 | rtx new_label = block_label (target); | |
883 | ||
6ee3c8e4 | 884 | if (target == EXIT_BLOCK_PTR) |
6de9cd9a | 885 | return NULL; |
ca6c03ca JH |
886 | if (GET_CODE (PATTERN (tmp)) == ADDR_VEC) |
887 | vec = XVEC (PATTERN (tmp), 0); | |
888 | else | |
889 | vec = XVEC (PATTERN (tmp), 1); | |
890 | ||
891 | for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j) | |
892 | if (XEXP (RTVEC_ELT (vec, j), 0) == old_label) | |
893 | { | |
894 | RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label); | |
895 | --LABEL_NUSES (old_label); | |
896 | ++LABEL_NUSES (new_label); | |
897 | } | |
898 | ||
f9da5064 | 899 | /* Handle casesi dispatch insns. */ |
ca6c03ca JH |
900 | if ((tmp = single_set (insn)) != NULL |
901 | && SET_DEST (tmp) == pc_rtx | |
902 | && GET_CODE (SET_SRC (tmp)) == IF_THEN_ELSE | |
903 | && GET_CODE (XEXP (SET_SRC (tmp), 2)) == LABEL_REF | |
904 | && XEXP (XEXP (SET_SRC (tmp), 2), 0) == old_label) | |
905 | { | |
4c33cb26 | 906 | XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode, |
ca6c03ca JH |
907 | new_label); |
908 | --LABEL_NUSES (old_label); | |
909 | ++LABEL_NUSES (new_label); | |
910 | } | |
911 | } | |
912 | else | |
913 | { | |
914 | /* ?? We may play the games with moving the named labels from | |
915 | one basic block to the other in case only one computed_jump is | |
916 | available. */ | |
5f0d2358 RK |
917 | if (computed_jump_p (insn) |
918 | /* A return instruction can't be redirected. */ | |
919 | || returnjump_p (insn)) | |
6de9cd9a | 920 | return NULL; |
ca6c03ca JH |
921 | |
922 | /* If the insn doesn't go where we think, we're confused. */ | |
341c100f | 923 | gcc_assert (JUMP_LABEL (insn) == old_label); |
6ee3c8e4 JJ |
924 | |
925 | /* If the substitution doesn't succeed, die. This can happen | |
926 | if the back end emitted unrecognizable instructions or if | |
927 | target is exit block on some arches. */ | |
928 | if (!redirect_jump (insn, block_label (target), 0)) | |
929 | { | |
341c100f NS |
930 | gcc_assert (target == EXIT_BLOCK_PTR); |
931 | return NULL; | |
6ee3c8e4 | 932 | } |
ca6c03ca JH |
933 | } |
934 | ||
c263766c RH |
935 | if (dump_file) |
936 | fprintf (dump_file, "Edge %i->%i redirected to %i\n", | |
0b17ab2f | 937 | e->src->index, e->dest->index, target->index); |
5f0d2358 | 938 | |
ca6c03ca | 939 | if (e->dest != target) |
6de9cd9a DN |
940 | e = redirect_edge_succ_nodup (e, target); |
941 | return e; | |
bc35512f JH |
942 | } |
943 | ||
944 | /* Attempt to change code to redirect edge E to TARGET. Don't do that on | |
945 | expense of adding new instructions or reordering basic blocks. | |
946 | ||
947 | Function can be also called with edge destination equivalent to the TARGET. | |
948 | Then it should try the simplifications and do nothing if none is possible. | |
949 | ||
6de9cd9a DN |
950 | Return edge representing the branch if transformation succeeded. Return NULL |
951 | on failure. | |
952 | We still return NULL in case E already destinated TARGET and we didn't | |
953 | managed to simplify instruction stream. */ | |
bc35512f | 954 | |
6de9cd9a | 955 | static edge |
5671bf27 | 956 | rtl_redirect_edge_and_branch (edge e, basic_block target) |
bc35512f | 957 | { |
6de9cd9a | 958 | edge ret; |
f345f21a JH |
959 | basic_block src = e->src; |
960 | ||
bc35512f | 961 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 962 | return NULL; |
bc35512f | 963 | |
3348b696 | 964 | if (e->dest == target) |
6de9cd9a | 965 | return e; |
3348b696 | 966 | |
6de9cd9a | 967 | if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL) |
f345f21a JH |
968 | { |
969 | src->flags |= BB_DIRTY; | |
6de9cd9a | 970 | return ret; |
f345f21a | 971 | } |
bc35512f | 972 | |
6de9cd9a DN |
973 | ret = redirect_branch_edge (e, target); |
974 | if (!ret) | |
975 | return NULL; | |
5f0d2358 | 976 | |
f345f21a | 977 | src->flags |= BB_DIRTY; |
6de9cd9a | 978 | return ret; |
ca6c03ca JH |
979 | } |
980 | ||
4fe9b91c | 981 | /* Like force_nonfallthru below, but additionally performs redirection |
ca6c03ca JH |
982 | Used by redirect_edge_and_branch_force. */ |
983 | ||
9167e1c0 | 984 | static basic_block |
d329e058 | 985 | force_nonfallthru_and_redirect (edge e, basic_block target) |
ca6c03ca | 986 | { |
a3716585 | 987 | basic_block jump_block, new_bb = NULL, src = e->src; |
ca6c03ca JH |
988 | rtx note; |
989 | edge new_edge; | |
a3716585 | 990 | int abnormal_edge_flags = 0; |
ca6c03ca | 991 | |
cb9a1d9b JH |
992 | /* In the case the last instruction is conditional jump to the next |
993 | instruction, first redirect the jump itself and then continue | |
b20b352b | 994 | by creating a basic block afterwards to redirect fallthru edge. */ |
cb9a1d9b | 995 | if (e->src != ENTRY_BLOCK_PTR && e->dest != EXIT_BLOCK_PTR |
a813c111 | 996 | && any_condjump_p (BB_END (e->src)) |
a813c111 | 997 | && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest)) |
cb9a1d9b JH |
998 | { |
999 | rtx note; | |
58e6ae30 | 1000 | edge b = unchecked_make_edge (e->src, target, 0); |
341c100f | 1001 | bool redirected; |
cb9a1d9b | 1002 | |
341c100f NS |
1003 | redirected = redirect_jump (BB_END (e->src), block_label (target), 0); |
1004 | gcc_assert (redirected); | |
c22cacf3 | 1005 | |
a813c111 | 1006 | note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX); |
cb9a1d9b JH |
1007 | if (note) |
1008 | { | |
1009 | int prob = INTVAL (XEXP (note, 0)); | |
1010 | ||
1011 | b->probability = prob; | |
1012 | b->count = e->count * prob / REG_BR_PROB_BASE; | |
1013 | e->probability -= e->probability; | |
1014 | e->count -= b->count; | |
1015 | if (e->probability < 0) | |
1016 | e->probability = 0; | |
1017 | if (e->count < 0) | |
1018 | e->count = 0; | |
1019 | } | |
1020 | } | |
1021 | ||
ca6c03ca | 1022 | if (e->flags & EDGE_ABNORMAL) |
a3716585 JH |
1023 | { |
1024 | /* Irritating special case - fallthru edge to the same block as abnormal | |
1025 | edge. | |
1026 | We can't redirect abnormal edge, but we still can split the fallthru | |
d329e058 | 1027 | one and create separate abnormal edge to original destination. |
a3716585 | 1028 | This allows bb-reorder to make such edge non-fallthru. */ |
341c100f | 1029 | gcc_assert (e->dest == target); |
a3716585 JH |
1030 | abnormal_edge_flags = e->flags & ~(EDGE_FALLTHRU | EDGE_CAN_FALLTHRU); |
1031 | e->flags &= EDGE_FALLTHRU | EDGE_CAN_FALLTHRU; | |
1032 | } | |
341c100f | 1033 | else |
24c545ff | 1034 | { |
341c100f NS |
1035 | gcc_assert (e->flags & EDGE_FALLTHRU); |
1036 | if (e->src == ENTRY_BLOCK_PTR) | |
1037 | { | |
1038 | /* We can't redirect the entry block. Create an empty block | |
628f6a4e BE |
1039 | at the start of the function which we use to add the new |
1040 | jump. */ | |
1041 | edge tmp; | |
1042 | edge_iterator ei; | |
1043 | bool found = false; | |
c22cacf3 | 1044 | |
628f6a4e | 1045 | basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL, ENTRY_BLOCK_PTR); |
c22cacf3 | 1046 | |
341c100f NS |
1047 | /* Change the existing edge's source to be the new block, and add |
1048 | a new edge from the entry block to the new block. */ | |
1049 | e->src = bb; | |
628f6a4e BE |
1050 | for (ei = ei_start (ENTRY_BLOCK_PTR->succs); (tmp = ei_safe_edge (ei)); ) |
1051 | { | |
1052 | if (tmp == e) | |
1053 | { | |
865851d0 | 1054 | VEC_unordered_remove (edge, ENTRY_BLOCK_PTR->succs, ei.index); |
628f6a4e BE |
1055 | found = true; |
1056 | break; | |
1057 | } | |
1058 | else | |
1059 | ei_next (&ei); | |
1060 | } | |
c22cacf3 | 1061 | |
628f6a4e | 1062 | gcc_assert (found); |
c22cacf3 | 1063 | |
d4e6fecb | 1064 | VEC_safe_push (edge, gc, bb->succs, e); |
341c100f NS |
1065 | make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU); |
1066 | } | |
24c545ff BS |
1067 | } |
1068 | ||
628f6a4e | 1069 | if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags) |
ca6c03ca JH |
1070 | { |
1071 | /* Create the new structures. */ | |
31a78298 | 1072 | |
79019985 RH |
1073 | /* If the old block ended with a tablejump, skip its table |
1074 | by searching forward from there. Otherwise start searching | |
1075 | forward from the last instruction of the old block. */ | |
a813c111 SB |
1076 | if (!tablejump_p (BB_END (e->src), NULL, ¬e)) |
1077 | note = BB_END (e->src); | |
31a78298 RH |
1078 | note = NEXT_INSN (note); |
1079 | ||
31a78298 | 1080 | jump_block = create_basic_block (note, NULL, e->src); |
ca6c03ca JH |
1081 | jump_block->count = e->count; |
1082 | jump_block->frequency = EDGE_FREQUENCY (e); | |
1083 | jump_block->loop_depth = target->loop_depth; | |
1084 | ||
5e2d947c | 1085 | if (target->il.rtl->global_live_at_start) |
ca6c03ca | 1086 | { |
5e2d947c JH |
1087 | jump_block->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack); |
1088 | jump_block->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack); | |
1089 | COPY_REG_SET (jump_block->il.rtl->global_live_at_start, | |
1090 | target->il.rtl->global_live_at_start); | |
1091 | COPY_REG_SET (jump_block->il.rtl->global_live_at_end, | |
1092 | target->il.rtl->global_live_at_start); | |
ca6c03ca JH |
1093 | } |
1094 | ||
750054a2 CT |
1095 | /* Make sure new block ends up in correct hot/cold section. */ |
1096 | ||
076c7ab8 | 1097 | BB_COPY_PARTITION (jump_block, e->src); |
9fb32434 | 1098 | if (flag_reorder_blocks_and_partition |
87c8b4be CT |
1099 | && targetm.have_named_sections |
1100 | && JUMP_P (BB_END (jump_block)) | |
1101 | && !any_condjump_p (BB_END (jump_block)) | |
1102 | && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING)) | |
1103 | REG_NOTES (BB_END (jump_block)) = gen_rtx_EXPR_LIST (REG_CROSSING_JUMP, | |
1104 | NULL_RTX, | |
1105 | REG_NOTES | |
1106 | (BB_END | |
c22cacf3 MS |
1107 | (jump_block))); |
1108 | ||
ca6c03ca JH |
1109 | /* Wire edge in. */ |
1110 | new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU); | |
1111 | new_edge->probability = e->probability; | |
1112 | new_edge->count = e->count; | |
1113 | ||
1114 | /* Redirect old edge. */ | |
1115 | redirect_edge_pred (e, jump_block); | |
1116 | e->probability = REG_BR_PROB_BASE; | |
1117 | ||
1118 | new_bb = jump_block; | |
1119 | } | |
1120 | else | |
1121 | jump_block = e->src; | |
5f0d2358 | 1122 | |
ca6c03ca JH |
1123 | e->flags &= ~EDGE_FALLTHRU; |
1124 | if (target == EXIT_BLOCK_PTR) | |
1125 | { | |
cf22ce3c | 1126 | #ifdef HAVE_return |
a7102479 | 1127 | emit_jump_insn_after_noloc (gen_return (), BB_END (jump_block)); |
cf22ce3c | 1128 | #else |
341c100f | 1129 | gcc_unreachable (); |
cf22ce3c | 1130 | #endif |
ca6c03ca JH |
1131 | } |
1132 | else | |
1133 | { | |
1134 | rtx label = block_label (target); | |
a7102479 | 1135 | emit_jump_insn_after_noloc (gen_jump (label), BB_END (jump_block)); |
a813c111 | 1136 | JUMP_LABEL (BB_END (jump_block)) = label; |
ca6c03ca JH |
1137 | LABEL_NUSES (label)++; |
1138 | } | |
5f0d2358 | 1139 | |
a813c111 | 1140 | emit_barrier_after (BB_END (jump_block)); |
ca6c03ca JH |
1141 | redirect_edge_succ_nodup (e, target); |
1142 | ||
a3716585 JH |
1143 | if (abnormal_edge_flags) |
1144 | make_edge (src, target, abnormal_edge_flags); | |
1145 | ||
ca6c03ca JH |
1146 | return new_bb; |
1147 | } | |
1148 | ||
1149 | /* Edge E is assumed to be fallthru edge. Emit needed jump instruction | |
1150 | (and possibly create new basic block) to make edge non-fallthru. | |
1151 | Return newly created BB or NULL if none. */ | |
5f0d2358 | 1152 | |
ca6c03ca | 1153 | basic_block |
d329e058 | 1154 | force_nonfallthru (edge e) |
ca6c03ca JH |
1155 | { |
1156 | return force_nonfallthru_and_redirect (e, e->dest); | |
1157 | } | |
1158 | ||
1159 | /* Redirect edge even at the expense of creating new jump insn or | |
1160 | basic block. Return new basic block if created, NULL otherwise. | |
41806d92 | 1161 | Conversion must be possible. */ |
ca6c03ca | 1162 | |
9ee634e3 | 1163 | static basic_block |
d329e058 | 1164 | rtl_redirect_edge_and_branch_force (edge e, basic_block target) |
ca6c03ca | 1165 | { |
5f0d2358 RK |
1166 | if (redirect_edge_and_branch (e, target) |
1167 | || e->dest == target) | |
ca6c03ca JH |
1168 | return NULL; |
1169 | ||
1170 | /* In case the edge redirection failed, try to force it to be non-fallthru | |
1171 | and redirect newly created simplejump. */ | |
c0c5d392 | 1172 | e->src->flags |= BB_DIRTY; |
5f0d2358 | 1173 | return force_nonfallthru_and_redirect (e, target); |
ca6c03ca JH |
1174 | } |
1175 | ||
1176 | /* The given edge should potentially be a fallthru edge. If that is in | |
1177 | fact true, delete the jump and barriers that are in the way. */ | |
1178 | ||
f470c378 ZD |
1179 | static void |
1180 | rtl_tidy_fallthru_edge (edge e) | |
ca6c03ca JH |
1181 | { |
1182 | rtx q; | |
f470c378 ZD |
1183 | basic_block b = e->src, c = b->next_bb; |
1184 | ||
ca6c03ca JH |
1185 | /* ??? In a late-running flow pass, other folks may have deleted basic |
1186 | blocks by nopping out blocks, leaving multiple BARRIERs between here | |
0fa2e4df | 1187 | and the target label. They ought to be chastised and fixed. |
ca6c03ca JH |
1188 | |
1189 | We can also wind up with a sequence of undeletable labels between | |
1190 | one block and the next. | |
1191 | ||
1192 | So search through a sequence of barriers, labels, and notes for | |
1193 | the head of block C and assert that we really do fall through. */ | |
1194 | ||
a813c111 | 1195 | for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q)) |
9c0a0632 RH |
1196 | if (INSN_P (q)) |
1197 | return; | |
ca6c03ca JH |
1198 | |
1199 | /* Remove what will soon cease being the jump insn from the source block. | |
1200 | If block B consisted only of this single jump, turn it into a deleted | |
1201 | note. */ | |
a813c111 | 1202 | q = BB_END (b); |
4b4bf941 | 1203 | if (JUMP_P (q) |
ca6c03ca JH |
1204 | && onlyjump_p (q) |
1205 | && (any_uncondjump_p (q) | |
c5cbcccf | 1206 | || single_succ_p (b))) |
ca6c03ca JH |
1207 | { |
1208 | #ifdef HAVE_cc0 | |
1209 | /* If this was a conditional jump, we need to also delete | |
1210 | the insn that set cc0. */ | |
1211 | if (any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q))) | |
1212 | q = PREV_INSN (q); | |
1213 | #endif | |
1214 | ||
1215 | q = PREV_INSN (q); | |
ca6c03ca JH |
1216 | } |
1217 | ||
1218 | /* Selectively unlink the sequence. */ | |
a813c111 SB |
1219 | if (q != PREV_INSN (BB_HEAD (c))) |
1220 | delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c))); | |
ca6c03ca JH |
1221 | |
1222 | e->flags |= EDGE_FALLTHRU; | |
1223 | } | |
ca6c03ca | 1224 | \f |
f470c378 ZD |
1225 | /* Should move basic block BB after basic block AFTER. NIY. */ |
1226 | ||
1227 | static bool | |
1228 | rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED, | |
1229 | basic_block after ATTRIBUTE_UNUSED) | |
1230 | { | |
1231 | return false; | |
1232 | } | |
1233 | ||
ca6c03ca | 1234 | /* Split a (typically critical) edge. Return the new block. |
41806d92 | 1235 | The edge must not be abnormal. |
ca6c03ca JH |
1236 | |
1237 | ??? The code generally expects to be called on critical edges. | |
1238 | The case of a block ending in an unconditional jump to a | |
1239 | block with multiple predecessors is not handled optimally. */ | |
1240 | ||
8ce33230 | 1241 | static basic_block |
d329e058 | 1242 | rtl_split_edge (edge edge_in) |
ca6c03ca JH |
1243 | { |
1244 | basic_block bb; | |
ca6c03ca JH |
1245 | rtx before; |
1246 | ||
1247 | /* Abnormal edges cannot be split. */ | |
341c100f | 1248 | gcc_assert (!(edge_in->flags & EDGE_ABNORMAL)); |
ca6c03ca JH |
1249 | |
1250 | /* We are going to place the new block in front of edge destination. | |
eaec9b3d | 1251 | Avoid existence of fallthru predecessors. */ |
ca6c03ca JH |
1252 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) |
1253 | { | |
1254 | edge e; | |
628f6a4e | 1255 | edge_iterator ei; |
5f0d2358 | 1256 | |
628f6a4e | 1257 | FOR_EACH_EDGE (e, ei, edge_in->dest->preds) |
ca6c03ca JH |
1258 | if (e->flags & EDGE_FALLTHRU) |
1259 | break; | |
1260 | ||
1261 | if (e) | |
1262 | force_nonfallthru (e); | |
1263 | } | |
1264 | ||
96e82e0a ZD |
1265 | /* Create the basic block note. */ |
1266 | if (edge_in->dest != EXIT_BLOCK_PTR) | |
a813c111 | 1267 | before = BB_HEAD (edge_in->dest); |
ca6c03ca JH |
1268 | else |
1269 | before = NULL_RTX; | |
1270 | ||
623a66fa R |
1271 | /* If this is a fall through edge to the exit block, the blocks might be |
1272 | not adjacent, and the right place is the after the source. */ | |
1273 | if (edge_in->flags & EDGE_FALLTHRU && edge_in->dest == EXIT_BLOCK_PTR) | |
1274 | { | |
1275 | before = NEXT_INSN (BB_END (edge_in->src)); | |
623a66fa | 1276 | bb = create_basic_block (before, NULL, edge_in->src); |
076c7ab8 | 1277 | BB_COPY_PARTITION (bb, edge_in->src); |
623a66fa R |
1278 | } |
1279 | else | |
9fb32434 CT |
1280 | { |
1281 | bb = create_basic_block (before, NULL, edge_in->dest->prev_bb); | |
076c7ab8 ZW |
1282 | /* ??? Why not edge_in->dest->prev_bb here? */ |
1283 | BB_COPY_PARTITION (bb, edge_in->dest); | |
9fb32434 | 1284 | } |
ca6c03ca JH |
1285 | |
1286 | /* ??? This info is likely going to be out of date very soon. */ | |
5e2d947c | 1287 | if (edge_in->dest->il.rtl->global_live_at_start) |
ca6c03ca | 1288 | { |
5e2d947c JH |
1289 | bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack); |
1290 | bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack); | |
1291 | COPY_REG_SET (bb->il.rtl->global_live_at_start, | |
1292 | edge_in->dest->il.rtl->global_live_at_start); | |
1293 | COPY_REG_SET (bb->il.rtl->global_live_at_end, | |
1294 | edge_in->dest->il.rtl->global_live_at_start); | |
ca6c03ca JH |
1295 | } |
1296 | ||
4977bab6 | 1297 | make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU); |
ca6c03ca | 1298 | |
4d6922ee | 1299 | /* For non-fallthru edges, we must adjust the predecessor's |
ca6c03ca JH |
1300 | jump instruction to target our new block. */ |
1301 | if ((edge_in->flags & EDGE_FALLTHRU) == 0) | |
1302 | { | |
341c100f NS |
1303 | edge redirected = redirect_edge_and_branch (edge_in, bb); |
1304 | gcc_assert (redirected); | |
ca6c03ca JH |
1305 | } |
1306 | else | |
1307 | redirect_edge_succ (edge_in, bb); | |
1308 | ||
1309 | return bb; | |
1310 | } | |
1311 | ||
1312 | /* Queue instructions for insertion on an edge between two basic blocks. | |
1313 | The new instructions and basic blocks (if any) will not appear in the | |
1314 | CFG until commit_edge_insertions is called. */ | |
1315 | ||
1316 | void | |
d329e058 | 1317 | insert_insn_on_edge (rtx pattern, edge e) |
ca6c03ca JH |
1318 | { |
1319 | /* We cannot insert instructions on an abnormal critical edge. | |
1320 | It will be easier to find the culprit if we die now. */ | |
341c100f | 1321 | gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))); |
ca6c03ca | 1322 | |
6de9cd9a | 1323 | if (e->insns.r == NULL_RTX) |
ca6c03ca JH |
1324 | start_sequence (); |
1325 | else | |
6de9cd9a | 1326 | push_to_sequence (e->insns.r); |
ca6c03ca JH |
1327 | |
1328 | emit_insn (pattern); | |
1329 | ||
6de9cd9a | 1330 | e->insns.r = get_insns (); |
ca6c03ca JH |
1331 | end_sequence (); |
1332 | } | |
1333 | ||
1334 | /* Update the CFG for the instructions queued on edge E. */ | |
1335 | ||
1336 | static void | |
2ac66157 | 1337 | commit_one_edge_insertion (edge e) |
ca6c03ca JH |
1338 | { |
1339 | rtx before = NULL_RTX, after = NULL_RTX, insns, tmp, last; | |
eae4bc56 | 1340 | basic_block bb = NULL; |
ca6c03ca JH |
1341 | |
1342 | /* Pull the insns off the edge now since the edge might go away. */ | |
6de9cd9a DN |
1343 | insns = e->insns.r; |
1344 | e->insns.r = NULL_RTX; | |
ca6c03ca | 1345 | |
3dec4024 | 1346 | if (!before && !after) |
ca6c03ca | 1347 | { |
3dec4024 | 1348 | /* Figure out where to put these things. If the destination has |
c22cacf3 | 1349 | one predecessor, insert there. Except for the exit block. */ |
c5cbcccf | 1350 | if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR) |
ca6c03ca | 1351 | { |
3dec4024 JH |
1352 | bb = e->dest; |
1353 | ||
1354 | /* Get the location correct wrt a code label, and "nice" wrt | |
1355 | a basic block note, and before everything else. */ | |
a813c111 | 1356 | tmp = BB_HEAD (bb); |
4b4bf941 | 1357 | if (LABEL_P (tmp)) |
3dec4024 JH |
1358 | tmp = NEXT_INSN (tmp); |
1359 | if (NOTE_INSN_BASIC_BLOCK_P (tmp)) | |
1360 | tmp = NEXT_INSN (tmp); | |
a813c111 | 1361 | if (tmp == BB_HEAD (bb)) |
3dec4024 JH |
1362 | before = tmp; |
1363 | else if (tmp) | |
1364 | after = PREV_INSN (tmp); | |
1365 | else | |
1366 | after = get_last_insn (); | |
1367 | } | |
1368 | ||
1369 | /* If the source has one successor and the edge is not abnormal, | |
c22cacf3 | 1370 | insert there. Except for the entry block. */ |
3dec4024 | 1371 | else if ((e->flags & EDGE_ABNORMAL) == 0 |
c5cbcccf | 1372 | && single_succ_p (e->src) |
3dec4024 JH |
1373 | && e->src != ENTRY_BLOCK_PTR) |
1374 | { | |
1375 | bb = e->src; | |
1376 | ||
1377 | /* It is possible to have a non-simple jump here. Consider a target | |
1378 | where some forms of unconditional jumps clobber a register. This | |
1379 | happens on the fr30 for example. | |
1380 | ||
1381 | We know this block has a single successor, so we can just emit | |
1382 | the queued insns before the jump. */ | |
4b4bf941 | 1383 | if (JUMP_P (BB_END (bb))) |
96e82e0a | 1384 | before = BB_END (bb); |
3dec4024 JH |
1385 | else |
1386 | { | |
341c100f NS |
1387 | /* We'd better be fallthru, or we've lost track of |
1388 | what's what. */ | |
1389 | gcc_assert (e->flags & EDGE_FALLTHRU); | |
ca6c03ca | 1390 | |
a813c111 | 1391 | after = BB_END (bb); |
3dec4024 JH |
1392 | } |
1393 | } | |
1394 | /* Otherwise we must split the edge. */ | |
1395 | else | |
1396 | { | |
1397 | bb = split_edge (e); | |
a813c111 | 1398 | after = BB_END (bb); |
750054a2 | 1399 | |
750054a2 | 1400 | if (flag_reorder_blocks_and_partition |
9fb32434 | 1401 | && targetm.have_named_sections |
750054a2 | 1402 | && e->src != ENTRY_BLOCK_PTR |
076c7ab8 | 1403 | && BB_PARTITION (e->src) == BB_COLD_PARTITION |
bd454efd | 1404 | && !(e->flags & EDGE_CROSSING)) |
750054a2 | 1405 | { |
87c8b4be | 1406 | rtx bb_note, cur_insn; |
750054a2 CT |
1407 | |
1408 | bb_note = NULL_RTX; | |
1409 | for (cur_insn = BB_HEAD (bb); cur_insn != NEXT_INSN (BB_END (bb)); | |
1410 | cur_insn = NEXT_INSN (cur_insn)) | |
4b4bf941 | 1411 | if (NOTE_P (cur_insn) |
750054a2 CT |
1412 | && NOTE_LINE_NUMBER (cur_insn) == NOTE_INSN_BASIC_BLOCK) |
1413 | { | |
1414 | bb_note = cur_insn; | |
1415 | break; | |
1416 | } | |
1417 | ||
4b4bf941 | 1418 | if (JUMP_P (BB_END (bb)) |
750054a2 | 1419 | && !any_condjump_p (BB_END (bb)) |
c22cacf3 MS |
1420 | && (single_succ_edge (bb)->flags & EDGE_CROSSING)) |
1421 | REG_NOTES (BB_END (bb)) = gen_rtx_EXPR_LIST | |
750054a2 | 1422 | (REG_CROSSING_JUMP, NULL_RTX, REG_NOTES (BB_END (bb))); |
750054a2 | 1423 | } |
ca6c03ca JH |
1424 | } |
1425 | } | |
1426 | ||
ca6c03ca JH |
1427 | /* Now that we've found the spot, do the insertion. */ |
1428 | ||
1429 | if (before) | |
1430 | { | |
a7102479 | 1431 | emit_insn_before_noloc (insns, before); |
ca6c03ca JH |
1432 | last = prev_nonnote_insn (before); |
1433 | } | |
1434 | else | |
a7102479 | 1435 | last = emit_insn_after_noloc (insns, after); |
ca6c03ca JH |
1436 | |
1437 | if (returnjump_p (last)) | |
1438 | { | |
1439 | /* ??? Remove all outgoing edges from BB and add one for EXIT. | |
c22cacf3 MS |
1440 | This is not currently a problem because this only happens |
1441 | for the (single) epilogue, which already has a fallthru edge | |
1442 | to EXIT. */ | |
ca6c03ca | 1443 | |
c5cbcccf | 1444 | e = single_succ_edge (bb); |
341c100f | 1445 | gcc_assert (e->dest == EXIT_BLOCK_PTR |
c5cbcccf | 1446 | && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU)); |
ca6c03ca | 1447 | |
5f0d2358 | 1448 | e->flags &= ~EDGE_FALLTHRU; |
ca6c03ca | 1449 | emit_barrier_after (last); |
0b17ab2f | 1450 | |
ca6c03ca JH |
1451 | if (before) |
1452 | delete_insn (before); | |
1453 | } | |
341c100f NS |
1454 | else |
1455 | gcc_assert (!JUMP_P (last)); | |
5f0d2358 | 1456 | |
12eff7b7 | 1457 | /* Mark the basic block for find_many_sub_basic_blocks. */ |
05549c96 SB |
1458 | if (current_ir_type () != IR_RTL_CFGLAYOUT) |
1459 | bb->aux = &bb->aux; | |
ca6c03ca JH |
1460 | } |
1461 | ||
1462 | /* Update the CFG for all queued instructions. */ | |
1463 | ||
1464 | void | |
d329e058 | 1465 | commit_edge_insertions (void) |
ca6c03ca | 1466 | { |
ca6c03ca | 1467 | basic_block bb; |
9dca2ad5 | 1468 | sbitmap blocks; |
9809a362 | 1469 | bool changed = false; |
ca6c03ca JH |
1470 | |
1471 | #ifdef ENABLE_CHECKING | |
1472 | verify_flow_info (); | |
1473 | #endif | |
1474 | ||
e0082a72 | 1475 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
ca6c03ca | 1476 | { |
628f6a4e BE |
1477 | edge e; |
1478 | edge_iterator ei; | |
ca6c03ca | 1479 | |
628f6a4e BE |
1480 | FOR_EACH_EDGE (e, ei, bb->succs) |
1481 | if (e->insns.r) | |
1482 | { | |
1483 | changed = true; | |
2ac66157 | 1484 | commit_one_edge_insertion (e); |
628f6a4e | 1485 | } |
3dec4024 | 1486 | } |
9dca2ad5 | 1487 | |
9809a362 JH |
1488 | if (!changed) |
1489 | return; | |
1490 | ||
05549c96 SB |
1491 | /* In the old rtl CFG API, it was OK to insert control flow on an |
1492 | edge, apparently? In cfglayout mode, this will *not* work, and | |
1493 | the caller is responsible for making sure that control flow is | |
1494 | valid at all times. */ | |
1495 | if (current_ir_type () == IR_RTL_CFGLAYOUT) | |
1496 | return; | |
1497 | ||
9809a362 JH |
1498 | blocks = sbitmap_alloc (last_basic_block); |
1499 | sbitmap_zero (blocks); | |
1500 | FOR_EACH_BB (bb) | |
1501 | if (bb->aux) | |
1502 | { | |
c22cacf3 | 1503 | SET_BIT (blocks, bb->index); |
9809a362 JH |
1504 | /* Check for forgotten bb->aux values before commit_edge_insertions |
1505 | call. */ | |
341c100f | 1506 | gcc_assert (bb->aux == &bb->aux); |
9809a362 JH |
1507 | bb->aux = NULL; |
1508 | } | |
1509 | find_many_sub_basic_blocks (blocks); | |
1510 | sbitmap_free (blocks); | |
ca6c03ca JH |
1511 | } |
1512 | \f | |
f470c378 ZD |
1513 | /* Print out RTL-specific basic block information (live information |
1514 | at start and end). */ | |
ca6c03ca | 1515 | |
10e9fecc | 1516 | static void |
f470c378 | 1517 | rtl_dump_bb (basic_block bb, FILE *outf, int indent) |
ca6c03ca JH |
1518 | { |
1519 | rtx insn; | |
1520 | rtx last; | |
f470c378 | 1521 | char *s_indent; |
ca6c03ca | 1522 | |
400e39e3 KH |
1523 | s_indent = alloca ((size_t) indent + 1); |
1524 | memset (s_indent, ' ', (size_t) indent); | |
f470c378 ZD |
1525 | s_indent[indent] = '\0'; |
1526 | ||
1527 | fprintf (outf, ";;%s Registers live at start: ", s_indent); | |
5e2d947c | 1528 | dump_regset (bb->il.rtl->global_live_at_start, outf); |
ca6c03ca JH |
1529 | putc ('\n', outf); |
1530 | ||
a813c111 | 1531 | for (insn = BB_HEAD (bb), last = NEXT_INSN (BB_END (bb)); insn != last; |
ca6c03ca JH |
1532 | insn = NEXT_INSN (insn)) |
1533 | print_rtl_single (outf, insn); | |
1534 | ||
f470c378 | 1535 | fprintf (outf, ";;%s Registers live at end: ", s_indent); |
5e2d947c | 1536 | dump_regset (bb->il.rtl->global_live_at_end, outf); |
ca6c03ca | 1537 | putc ('\n', outf); |
ca6c03ca JH |
1538 | } |
1539 | \f | |
1540 | /* Like print_rtl, but also print out live information for the start of each | |
1541 | basic block. */ | |
1542 | ||
1543 | void | |
d329e058 | 1544 | print_rtl_with_bb (FILE *outf, rtx rtx_first) |
ca6c03ca | 1545 | { |
b3694847 | 1546 | rtx tmp_rtx; |
ca6c03ca JH |
1547 | |
1548 | if (rtx_first == 0) | |
1549 | fprintf (outf, "(nil)\n"); | |
1550 | else | |
1551 | { | |
ca6c03ca JH |
1552 | enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB }; |
1553 | int max_uid = get_max_uid (); | |
5ed6ace5 MD |
1554 | basic_block *start = XCNEWVEC (basic_block, max_uid); |
1555 | basic_block *end = XCNEWVEC (basic_block, max_uid); | |
1556 | enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid); | |
ca6c03ca | 1557 | |
e0082a72 ZD |
1558 | basic_block bb; |
1559 | ||
1560 | FOR_EACH_BB_REVERSE (bb) | |
ca6c03ca | 1561 | { |
ca6c03ca JH |
1562 | rtx x; |
1563 | ||
a813c111 SB |
1564 | start[INSN_UID (BB_HEAD (bb))] = bb; |
1565 | end[INSN_UID (BB_END (bb))] = bb; | |
1566 | for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x)) | |
ca6c03ca JH |
1567 | { |
1568 | enum bb_state state = IN_MULTIPLE_BB; | |
5f0d2358 | 1569 | |
ca6c03ca JH |
1570 | if (in_bb_p[INSN_UID (x)] == NOT_IN_BB) |
1571 | state = IN_ONE_BB; | |
1572 | in_bb_p[INSN_UID (x)] = state; | |
1573 | ||
a813c111 | 1574 | if (x == BB_END (bb)) |
ca6c03ca JH |
1575 | break; |
1576 | } | |
1577 | } | |
1578 | ||
1579 | for (tmp_rtx = rtx_first; NULL != tmp_rtx; tmp_rtx = NEXT_INSN (tmp_rtx)) | |
1580 | { | |
1581 | int did_output; | |
e9ec5c6b SB |
1582 | edge_iterator ei; |
1583 | edge e; | |
ca6c03ca JH |
1584 | |
1585 | if ((bb = start[INSN_UID (tmp_rtx)]) != NULL) | |
1586 | { | |
1587 | fprintf (outf, ";; Start of basic block %d, registers live:", | |
0b17ab2f | 1588 | bb->index); |
5e2d947c | 1589 | dump_regset (bb->il.rtl->global_live_at_start, outf); |
ca6c03ca | 1590 | putc ('\n', outf); |
e9ec5c6b SB |
1591 | FOR_EACH_EDGE (e, ei, bb->preds) |
1592 | { | |
1593 | fputs (";; Pred edge ", outf); | |
1594 | dump_edge_info (outf, e, 0); | |
1595 | fputc ('\n', outf); | |
1596 | } | |
ca6c03ca JH |
1597 | } |
1598 | ||
1599 | if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB | |
4b4bf941 JQ |
1600 | && !NOTE_P (tmp_rtx) |
1601 | && !BARRIER_P (tmp_rtx)) | |
ca6c03ca JH |
1602 | fprintf (outf, ";; Insn is not within a basic block\n"); |
1603 | else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB) | |
1604 | fprintf (outf, ";; Insn is in multiple basic blocks\n"); | |
1605 | ||
1606 | did_output = print_rtl_single (outf, tmp_rtx); | |
1607 | ||
1608 | if ((bb = end[INSN_UID (tmp_rtx)]) != NULL) | |
1609 | { | |
e9ec5c6b | 1610 | fprintf (outf, ";; End of basic block %d, registers live:", |
0b17ab2f | 1611 | bb->index); |
5e2d947c | 1612 | dump_regset (bb->il.rtl->global_live_at_end, outf); |
ca6c03ca | 1613 | putc ('\n', outf); |
e9ec5c6b SB |
1614 | FOR_EACH_EDGE (e, ei, bb->succs) |
1615 | { | |
1616 | fputs (";; Succ edge ", outf); | |
1617 | dump_edge_info (outf, e, 1); | |
1618 | fputc ('\n', outf); | |
1619 | } | |
ca6c03ca JH |
1620 | } |
1621 | ||
1622 | if (did_output) | |
1623 | putc ('\n', outf); | |
1624 | } | |
1625 | ||
1626 | free (start); | |
1627 | free (end); | |
1628 | free (in_bb_p); | |
1629 | } | |
1630 | ||
1631 | if (current_function_epilogue_delay_list != 0) | |
1632 | { | |
1633 | fprintf (outf, "\n;; Insns in epilogue delay list:\n\n"); | |
1634 | for (tmp_rtx = current_function_epilogue_delay_list; tmp_rtx != 0; | |
1635 | tmp_rtx = XEXP (tmp_rtx, 1)) | |
1636 | print_rtl_single (outf, XEXP (tmp_rtx, 0)); | |
1637 | } | |
1638 | } | |
1639 | \f | |
b446e5a2 | 1640 | void |
d329e058 | 1641 | update_br_prob_note (basic_block bb) |
b446e5a2 JH |
1642 | { |
1643 | rtx note; | |
4b4bf941 | 1644 | if (!JUMP_P (BB_END (bb))) |
b446e5a2 | 1645 | return; |
a813c111 | 1646 | note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX); |
b446e5a2 JH |
1647 | if (!note || INTVAL (XEXP (note, 0)) == BRANCH_EDGE (bb)->probability) |
1648 | return; | |
1649 | XEXP (note, 0) = GEN_INT (BRANCH_EDGE (bb)->probability); | |
1650 | } | |
96370780 MK |
1651 | |
1652 | /* Get the last insn associated with block BB (that includes barriers and | |
1653 | tablejumps after BB). */ | |
1654 | rtx | |
1655 | get_last_bb_insn (basic_block bb) | |
1656 | { | |
1657 | rtx tmp; | |
1658 | rtx end = BB_END (bb); | |
1659 | ||
1660 | /* Include any jump table following the basic block. */ | |
1661 | if (tablejump_p (end, NULL, &tmp)) | |
1662 | end = tmp; | |
1663 | ||
1664 | /* Include any barriers that may follow the basic block. */ | |
1665 | tmp = next_nonnote_insn (end); | |
1666 | while (tmp && BARRIER_P (tmp)) | |
1667 | { | |
1668 | end = tmp; | |
1669 | tmp = next_nonnote_insn (end); | |
1670 | } | |
1671 | ||
1672 | return end; | |
1673 | } | |
b446e5a2 | 1674 | \f |
10e9fecc JH |
1675 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
1676 | cfglayout RTL. | |
ca6c03ca JH |
1677 | |
1678 | Currently it does following checks: | |
1679 | ||
ca6c03ca | 1680 | - overlapping of basic blocks |
9eab6785 | 1681 | - insns with wrong BLOCK_FOR_INSN pointers |
ca6c03ca | 1682 | - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note) |
f63d1bf7 | 1683 | - tails of basic blocks (ensure that boundary is necessary) |
ca6c03ca JH |
1684 | - scans body of the basic block for JUMP_INSN, CODE_LABEL |
1685 | and NOTE_INSN_BASIC_BLOCK | |
750054a2 | 1686 | - verify that no fall_thru edge crosses hot/cold partition boundaries |
9eab6785 | 1687 | - verify that there are no pending RTL branch predictions |
ca6c03ca JH |
1688 | |
1689 | In future it can be extended check a lot of other stuff as well | |
1690 | (reachability of basic blocks, life information, etc. etc.). */ | |
f470c378 | 1691 | |
10e9fecc | 1692 | static int |
d329e058 | 1693 | rtl_verify_flow_info_1 (void) |
ca6c03ca | 1694 | { |
ca6c03ca | 1695 | rtx x; |
10e9fecc | 1696 | int err = 0; |
94eb5ddb | 1697 | basic_block bb; |
ca6c03ca | 1698 | |
9eab6785 | 1699 | /* Check the general integrity of the basic blocks. */ |
e0082a72 | 1700 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1701 | { |
9eab6785 | 1702 | rtx insn; |
5f0d2358 | 1703 | |
5e2d947c JH |
1704 | if (!(bb->flags & BB_RTL)) |
1705 | { | |
1706 | error ("BB_RTL flag not set for block %d", bb->index); | |
1707 | err = 1; | |
1708 | } | |
1709 | ||
9eab6785 SB |
1710 | FOR_BB_INSNS (bb, insn) |
1711 | if (BLOCK_FOR_INSN (insn) != bb) | |
1712 | { | |
1713 | error ("insn %d basic block pointer is %d, should be %d", | |
1714 | INSN_UID (insn), | |
1715 | BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0, | |
1716 | bb->index); | |
1717 | err = 1; | |
1718 | } | |
ca6c03ca | 1719 | |
9eab6785 | 1720 | if (bb->predictions) |
ca6c03ca | 1721 | { |
9eab6785 | 1722 | error ("bb prediction set for block %d, but it is not used in RTL land", bb->index); |
ca6c03ca JH |
1723 | err = 1; |
1724 | } | |
ca6c03ca JH |
1725 | } |
1726 | ||
1727 | /* Now check the basic blocks (boundaries etc.) */ | |
e0082a72 | 1728 | FOR_EACH_BB_REVERSE (bb) |
ca6c03ca | 1729 | { |
3dec4024 | 1730 | int n_fallthru = 0, n_eh = 0, n_call = 0, n_abnormal = 0, n_branch = 0; |
3cf54412 | 1731 | edge e, fallthru = NULL; |
5a1a3e5e | 1732 | rtx note; |
628f6a4e | 1733 | edge_iterator ei; |
ca6c03ca | 1734 | |
2085a21f | 1735 | if (JUMP_P (BB_END (bb)) |
a813c111 | 1736 | && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX)) |
628f6a4e | 1737 | && EDGE_COUNT (bb->succs) >= 2 |
a813c111 | 1738 | && any_condjump_p (BB_END (bb))) |
5a1a3e5e | 1739 | { |
e53de54d JH |
1740 | if (INTVAL (XEXP (note, 0)) != BRANCH_EDGE (bb)->probability |
1741 | && profile_status != PROFILE_ABSENT) | |
5a1a3e5e | 1742 | { |
0108ae51 | 1743 | error ("verify_flow_info: REG_BR_PROB does not match cfg %wi %i", |
5a1a3e5e JH |
1744 | INTVAL (XEXP (note, 0)), BRANCH_EDGE (bb)->probability); |
1745 | err = 1; | |
1746 | } | |
1747 | } | |
628f6a4e | 1748 | FOR_EACH_EDGE (e, ei, bb->succs) |
ca6c03ca | 1749 | { |
ca6c03ca | 1750 | if (e->flags & EDGE_FALLTHRU) |
750054a2 CT |
1751 | { |
1752 | n_fallthru++, fallthru = e; | |
bd454efd | 1753 | if ((e->flags & EDGE_CROSSING) |
076c7ab8 | 1754 | || (BB_PARTITION (e->src) != BB_PARTITION (e->dest) |
9fb32434 CT |
1755 | && e->src != ENTRY_BLOCK_PTR |
1756 | && e->dest != EXIT_BLOCK_PTR)) | |
c22cacf3 | 1757 | { |
ab532386 | 1758 | error ("fallthru edge crosses section boundary (bb %i)", |
750054a2 CT |
1759 | e->src->index); |
1760 | err = 1; | |
1761 | } | |
1762 | } | |
3dec4024 | 1763 | |
65f43cdf ZD |
1764 | if ((e->flags & ~(EDGE_DFS_BACK |
1765 | | EDGE_CAN_FALLTHRU | |
1766 | | EDGE_IRREDUCIBLE_LOOP | |
9beb1c84 CT |
1767 | | EDGE_LOOP_EXIT |
1768 | | EDGE_CROSSING)) == 0) | |
3dec4024 JH |
1769 | n_branch++; |
1770 | ||
1771 | if (e->flags & EDGE_ABNORMAL_CALL) | |
1772 | n_call++; | |
1773 | ||
1774 | if (e->flags & EDGE_EH) | |
1775 | n_eh++; | |
1776 | else if (e->flags & EDGE_ABNORMAL) | |
1777 | n_abnormal++; | |
ca6c03ca | 1778 | } |
5f0d2358 | 1779 | |
a813c111 SB |
1780 | if (n_eh && GET_CODE (PATTERN (BB_END (bb))) != RESX |
1781 | && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX)) | |
3dec4024 | 1782 | { |
ab532386 | 1783 | error ("missing REG_EH_REGION note in the end of bb %i", bb->index); |
3dec4024 JH |
1784 | err = 1; |
1785 | } | |
1786 | if (n_branch | |
4b4bf941 | 1787 | && (!JUMP_P (BB_END (bb)) |
a813c111 SB |
1788 | || (n_branch > 1 && (any_uncondjump_p (BB_END (bb)) |
1789 | || any_condjump_p (BB_END (bb)))))) | |
3dec4024 | 1790 | { |
ab532386 | 1791 | error ("too many outgoing branch edges from bb %i", bb->index); |
3dec4024 JH |
1792 | err = 1; |
1793 | } | |
a813c111 | 1794 | if (n_fallthru && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 1795 | { |
ab532386 | 1796 | error ("fallthru edge after unconditional jump %i", bb->index); |
3dec4024 JH |
1797 | err = 1; |
1798 | } | |
a813c111 | 1799 | if (n_branch != 1 && any_uncondjump_p (BB_END (bb))) |
3dec4024 | 1800 | { |
ab532386 | 1801 | error ("wrong amount of branch edges after unconditional jump %i", bb->index); |
3dec4024 JH |
1802 | err = 1; |
1803 | } | |
a813c111 | 1804 | if (n_branch != 1 && any_condjump_p (BB_END (bb)) |
c11fd0b2 | 1805 | && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest)) |
3dec4024 | 1806 | { |
c11fd0b2 RG |
1807 | error ("wrong amount of branch edges after conditional jump %i", |
1808 | bb->index); | |
3dec4024 JH |
1809 | err = 1; |
1810 | } | |
4b4bf941 | 1811 | if (n_call && !CALL_P (BB_END (bb))) |
3dec4024 | 1812 | { |
ab532386 | 1813 | error ("call edges for non-call insn in bb %i", bb->index); |
3dec4024 JH |
1814 | err = 1; |
1815 | } | |
1816 | if (n_abnormal | |
4b4bf941 JQ |
1817 | && (!CALL_P (BB_END (bb)) && n_call != n_abnormal) |
1818 | && (!JUMP_P (BB_END (bb)) | |
a813c111 SB |
1819 | || any_condjump_p (BB_END (bb)) |
1820 | || any_uncondjump_p (BB_END (bb)))) | |
3dec4024 | 1821 | { |
ab532386 | 1822 | error ("abnormal edges for no purpose in bb %i", bb->index); |
3dec4024 JH |
1823 | err = 1; |
1824 | } | |
f87c27b4 | 1825 | |
a813c111 | 1826 | for (x = BB_HEAD (bb); x != NEXT_INSN (BB_END (bb)); x = NEXT_INSN (x)) |
0ca541aa | 1827 | /* We may have a barrier inside a basic block before dead code |
9524880c HPN |
1828 | elimination. There is no BLOCK_FOR_INSN field in a barrier. */ |
1829 | if (!BARRIER_P (x) && BLOCK_FOR_INSN (x) != bb) | |
5f0d2358 RK |
1830 | { |
1831 | debug_rtx (x); | |
1832 | if (! BLOCK_FOR_INSN (x)) | |
1833 | error | |
1834 | ("insn %d inside basic block %d but block_for_insn is NULL", | |
0b17ab2f | 1835 | INSN_UID (x), bb->index); |
5f0d2358 RK |
1836 | else |
1837 | error | |
1838 | ("insn %d inside basic block %d but block_for_insn is %i", | |
0b17ab2f | 1839 | INSN_UID (x), bb->index, BLOCK_FOR_INSN (x)->index); |
5f0d2358 RK |
1840 | |
1841 | err = 1; | |
1842 | } | |
ca6c03ca JH |
1843 | |
1844 | /* OK pointers are correct. Now check the header of basic | |
c22cacf3 | 1845 | block. It ought to contain optional CODE_LABEL followed |
ca6c03ca | 1846 | by NOTE_BASIC_BLOCK. */ |
a813c111 | 1847 | x = BB_HEAD (bb); |
4b4bf941 | 1848 | if (LABEL_P (x)) |
ca6c03ca | 1849 | { |
a813c111 | 1850 | if (BB_END (bb) == x) |
ca6c03ca JH |
1851 | { |
1852 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 1853 | bb->index); |
ca6c03ca JH |
1854 | err = 1; |
1855 | } | |
5f0d2358 | 1856 | |
ca6c03ca JH |
1857 | x = NEXT_INSN (x); |
1858 | } | |
5f0d2358 | 1859 | |
ca6c03ca JH |
1860 | if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb) |
1861 | { | |
1862 | error ("NOTE_INSN_BASIC_BLOCK is missing for block %d", | |
0b17ab2f | 1863 | bb->index); |
ca6c03ca JH |
1864 | err = 1; |
1865 | } | |
1866 | ||
a813c111 | 1867 | if (BB_END (bb) == x) |
49243025 | 1868 | /* Do checks for empty blocks here. */ |
5f0d2358 | 1869 | ; |
ca6c03ca | 1870 | else |
5f0d2358 RK |
1871 | for (x = NEXT_INSN (x); x; x = NEXT_INSN (x)) |
1872 | { | |
1873 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
1874 | { | |
1875 | error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d", | |
0b17ab2f | 1876 | INSN_UID (x), bb->index); |
5f0d2358 RK |
1877 | err = 1; |
1878 | } | |
1879 | ||
a813c111 | 1880 | if (x == BB_END (bb)) |
5f0d2358 | 1881 | break; |
ca6c03ca | 1882 | |
83fd323c | 1883 | if (control_flow_insn_p (x)) |
5f0d2358 | 1884 | { |
0b17ab2f | 1885 | error ("in basic block %d:", bb->index); |
5f0d2358 RK |
1886 | fatal_insn ("flow control insn inside a basic block", x); |
1887 | } | |
1888 | } | |
ca6c03ca JH |
1889 | } |
1890 | ||
10e9fecc | 1891 | /* Clean up. */ |
10e9fecc JH |
1892 | return err; |
1893 | } | |
5f0d2358 | 1894 | |
10e9fecc JH |
1895 | /* Verify the CFG and RTL consistency common for both underlying RTL and |
1896 | cfglayout RTL. | |
5f0d2358 | 1897 | |
10e9fecc JH |
1898 | Currently it does following checks: |
1899 | - all checks of rtl_verify_flow_info_1 | |
9eab6785 | 1900 | - test head/end pointers |
10e9fecc JH |
1901 | - check that all insns are in the basic blocks |
1902 | (except the switch handling code, barriers and notes) | |
1903 | - check that all returns are followed by barriers | |
1904 | - check that all fallthru edge points to the adjacent blocks. */ | |
9eab6785 | 1905 | |
10e9fecc | 1906 | static int |
d329e058 | 1907 | rtl_verify_flow_info (void) |
10e9fecc JH |
1908 | { |
1909 | basic_block bb; | |
1910 | int err = rtl_verify_flow_info_1 (); | |
1911 | rtx x; | |
9eab6785 SB |
1912 | rtx last_head = get_last_insn (); |
1913 | basic_block *bb_info; | |
10e9fecc JH |
1914 | int num_bb_notes; |
1915 | const rtx rtx_first = get_insns (); | |
1916 | basic_block last_bb_seen = ENTRY_BLOCK_PTR, curr_bb = NULL; | |
9eab6785 SB |
1917 | const int max_uid = get_max_uid (); |
1918 | ||
1919 | bb_info = XCNEWVEC (basic_block, max_uid); | |
ca6c03ca | 1920 | |
10e9fecc JH |
1921 | FOR_EACH_BB_REVERSE (bb) |
1922 | { | |
1923 | edge e; | |
628f6a4e | 1924 | edge_iterator ei; |
9eab6785 SB |
1925 | rtx head = BB_HEAD (bb); |
1926 | rtx end = BB_END (bb); | |
628f6a4e | 1927 | |
9eab6785 SB |
1928 | /* Verify the end of the basic block is in the INSN chain. */ |
1929 | for (x = last_head; x != NULL_RTX; x = PREV_INSN (x)) | |
1930 | if (x == end) | |
1931 | break; | |
1932 | ||
1933 | if (!x) | |
1934 | { | |
1935 | error ("end insn %d for block %d not found in the insn stream", | |
1936 | INSN_UID (end), bb->index); | |
1937 | err = 1; | |
1938 | } | |
1939 | ||
1940 | /* Work backwards from the end to the head of the basic block | |
1941 | to verify the head is in the RTL chain. */ | |
1942 | for (; x != NULL_RTX; x = PREV_INSN (x)) | |
a00d11f0 | 1943 | { |
9eab6785 SB |
1944 | /* While walking over the insn chain, verify insns appear |
1945 | in only one basic block. */ | |
1946 | if (bb_info[INSN_UID (x)] != NULL) | |
1947 | { | |
1948 | error ("insn %d is in multiple basic blocks (%d and %d)", | |
1949 | INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index); | |
1950 | err = 1; | |
1951 | } | |
1952 | ||
1953 | bb_info[INSN_UID (x)] = bb; | |
1954 | ||
1955 | if (x == head) | |
1956 | break; | |
1957 | } | |
1958 | if (!x) | |
1959 | { | |
1960 | error ("head insn %d for block %d not found in the insn stream", | |
1961 | INSN_UID (head), bb->index); | |
a00d11f0 JH |
1962 | err = 1; |
1963 | } | |
1964 | ||
9eab6785 SB |
1965 | last_head = x; |
1966 | ||
628f6a4e | 1967 | FOR_EACH_EDGE (e, ei, bb->succs) |
10e9fecc JH |
1968 | if (e->flags & EDGE_FALLTHRU) |
1969 | break; | |
1970 | if (!e) | |
1971 | { | |
1972 | rtx insn; | |
1973 | ||
1974 | /* Ensure existence of barrier in BB with no fallthru edges. */ | |
4b4bf941 | 1975 | for (insn = BB_END (bb); !insn || !BARRIER_P (insn); |
10e9fecc JH |
1976 | insn = NEXT_INSN (insn)) |
1977 | if (!insn | |
4b4bf941 | 1978 | || (NOTE_P (insn) |
10e9fecc JH |
1979 | && NOTE_LINE_NUMBER (insn) == NOTE_INSN_BASIC_BLOCK)) |
1980 | { | |
1981 | error ("missing barrier after block %i", bb->index); | |
1982 | err = 1; | |
1983 | break; | |
1984 | } | |
1985 | } | |
1986 | else if (e->src != ENTRY_BLOCK_PTR | |
1987 | && e->dest != EXIT_BLOCK_PTR) | |
c22cacf3 | 1988 | { |
10e9fecc JH |
1989 | rtx insn; |
1990 | ||
1991 | if (e->src->next_bb != e->dest) | |
1992 | { | |
1993 | error | |
1994 | ("verify_flow_info: Incorrect blocks for fallthru %i->%i", | |
1995 | e->src->index, e->dest->index); | |
1996 | err = 1; | |
1997 | } | |
1998 | else | |
a813c111 | 1999 | for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest); |
10e9fecc | 2000 | insn = NEXT_INSN (insn)) |
6be85b25 | 2001 | if (BARRIER_P (insn) || INSN_P (insn)) |
10e9fecc JH |
2002 | { |
2003 | error ("verify_flow_info: Incorrect fallthru %i->%i", | |
2004 | e->src->index, e->dest->index); | |
2005 | fatal_insn ("wrong insn in the fallthru edge", insn); | |
2006 | err = 1; | |
2007 | } | |
c22cacf3 | 2008 | } |
10e9fecc | 2009 | } |
ca6c03ca | 2010 | |
9eab6785 SB |
2011 | free (bb_info); |
2012 | ||
ca6c03ca | 2013 | num_bb_notes = 0; |
e0082a72 ZD |
2014 | last_bb_seen = ENTRY_BLOCK_PTR; |
2015 | ||
5f0d2358 | 2016 | for (x = rtx_first; x; x = NEXT_INSN (x)) |
ca6c03ca JH |
2017 | { |
2018 | if (NOTE_INSN_BASIC_BLOCK_P (x)) | |
2019 | { | |
bf77398c | 2020 | bb = NOTE_BASIC_BLOCK (x); |
5f0d2358 | 2021 | |
ca6c03ca | 2022 | num_bb_notes++; |
e0082a72 | 2023 | if (bb != last_bb_seen->next_bb) |
10e9fecc | 2024 | internal_error ("basic blocks not laid down consecutively"); |
ca6c03ca | 2025 | |
10e9fecc | 2026 | curr_bb = last_bb_seen = bb; |
ca6c03ca JH |
2027 | } |
2028 | ||
10e9fecc | 2029 | if (!curr_bb) |
ca6c03ca JH |
2030 | { |
2031 | switch (GET_CODE (x)) | |
2032 | { | |
2033 | case BARRIER: | |
2034 | case NOTE: | |
2035 | break; | |
2036 | ||
2037 | case CODE_LABEL: | |
666c27b9 | 2038 | /* An addr_vec is placed outside any basic block. */ |
ca6c03ca | 2039 | if (NEXT_INSN (x) |
4b4bf941 | 2040 | && JUMP_P (NEXT_INSN (x)) |
ca6c03ca JH |
2041 | && (GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_DIFF_VEC |
2042 | || GET_CODE (PATTERN (NEXT_INSN (x))) == ADDR_VEC)) | |
5f0d2358 | 2043 | x = NEXT_INSN (x); |
ca6c03ca JH |
2044 | |
2045 | /* But in any case, non-deletable labels can appear anywhere. */ | |
2046 | break; | |
2047 | ||
2048 | default: | |
1f978f5f | 2049 | fatal_insn ("insn outside basic block", x); |
ca6c03ca JH |
2050 | } |
2051 | } | |
2052 | ||
26cae194 | 2053 | if (JUMP_P (x) |
ca6c03ca | 2054 | && returnjump_p (x) && ! condjump_p (x) |
4b4bf941 | 2055 | && ! (NEXT_INSN (x) && BARRIER_P (NEXT_INSN (x)))) |
1f978f5f | 2056 | fatal_insn ("return not followed by barrier", x); |
a813c111 | 2057 | if (curr_bb && x == BB_END (curr_bb)) |
10e9fecc | 2058 | curr_bb = NULL; |
ca6c03ca JH |
2059 | } |
2060 | ||
24bd1a0b | 2061 | if (num_bb_notes != n_basic_blocks - NUM_FIXED_BLOCKS) |
ca6c03ca | 2062 | internal_error |
0b17ab2f RH |
2063 | ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)", |
2064 | num_bb_notes, n_basic_blocks); | |
ca6c03ca | 2065 | |
10e9fecc | 2066 | return err; |
ca6c03ca JH |
2067 | } |
2068 | \f | |
eaec9b3d | 2069 | /* Assume that the preceding pass has possibly eliminated jump instructions |
ca6c03ca JH |
2070 | or converted the unconditional jumps. Eliminate the edges from CFG. |
2071 | Return true if any edges are eliminated. */ | |
2072 | ||
2073 | bool | |
d329e058 | 2074 | purge_dead_edges (basic_block bb) |
ca6c03ca | 2075 | { |
628f6a4e | 2076 | edge e; |
a813c111 | 2077 | rtx insn = BB_END (bb), note; |
ca6c03ca | 2078 | bool purged = false; |
628f6a4e BE |
2079 | bool found; |
2080 | edge_iterator ei; | |
ca6c03ca | 2081 | |
70da1d03 | 2082 | /* If this instruction cannot trap, remove REG_EH_REGION notes. */ |
4b4bf941 | 2083 | if (NONJUMP_INSN_P (insn) |
70da1d03 JH |
2084 | && (note = find_reg_note (insn, REG_EH_REGION, NULL))) |
2085 | { | |
2086 | rtx eqnote; | |
2087 | ||
2088 | if (! may_trap_p (PATTERN (insn)) | |
2089 | || ((eqnote = find_reg_equal_equiv_note (insn)) | |
2090 | && ! may_trap_p (XEXP (eqnote, 0)))) | |
2091 | remove_note (insn, note); | |
2092 | } | |
2093 | ||
546c093e | 2094 | /* Cleanup abnormal edges caused by exceptions or non-local gotos. */ |
628f6a4e | 2095 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
546c093e | 2096 | { |
e5f9a909 JW |
2097 | /* There are three types of edges we need to handle correctly here: EH |
2098 | edges, abnormal call EH edges, and abnormal call non-EH edges. The | |
2099 | latter can appear when nonlocal gotos are used. */ | |
2100 | if (e->flags & EDGE_EH) | |
546c093e | 2101 | { |
e5f9a909 JW |
2102 | if (can_throw_internal (BB_END (bb)) |
2103 | /* If this is a call edge, verify that this is a call insn. */ | |
2104 | && (! (e->flags & EDGE_ABNORMAL_CALL) | |
2105 | || CALL_P (BB_END (bb)))) | |
628f6a4e BE |
2106 | { |
2107 | ei_next (&ei); | |
2108 | continue; | |
2109 | } | |
546c093e | 2110 | } |
e5f9a909 | 2111 | else if (e->flags & EDGE_ABNORMAL_CALL) |
546c093e | 2112 | { |
e5f9a909 JW |
2113 | if (CALL_P (BB_END (bb)) |
2114 | && (! (note = find_reg_note (insn, REG_EH_REGION, NULL)) | |
2115 | || INTVAL (XEXP (note, 0)) >= 0)) | |
628f6a4e BE |
2116 | { |
2117 | ei_next (&ei); | |
2118 | continue; | |
2119 | } | |
546c093e RH |
2120 | } |
2121 | else | |
628f6a4e BE |
2122 | { |
2123 | ei_next (&ei); | |
2124 | continue; | |
2125 | } | |
546c093e RH |
2126 | |
2127 | remove_edge (e); | |
2128 | bb->flags |= BB_DIRTY; | |
2129 | purged = true; | |
2130 | } | |
5f0d2358 | 2131 | |
4b4bf941 | 2132 | if (JUMP_P (insn)) |
ca6c03ca JH |
2133 | { |
2134 | rtx note; | |
2135 | edge b,f; | |
628f6a4e | 2136 | edge_iterator ei; |
5f0d2358 | 2137 | |
ca6c03ca JH |
2138 | /* We do care only about conditional jumps and simplejumps. */ |
2139 | if (!any_condjump_p (insn) | |
2140 | && !returnjump_p (insn) | |
2141 | && !simplejump_p (insn)) | |
c51d95ec | 2142 | return purged; |
5f0d2358 | 2143 | |
5a1a3e5e JH |
2144 | /* Branch probability/prediction notes are defined only for |
2145 | condjumps. We've possibly turned condjump into simplejump. */ | |
2146 | if (simplejump_p (insn)) | |
2147 | { | |
2148 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2149 | if (note) | |
2150 | remove_note (insn, note); | |
2151 | while ((note = find_reg_note (insn, REG_BR_PRED, NULL))) | |
2152 | remove_note (insn, note); | |
2153 | } | |
2154 | ||
628f6a4e | 2155 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2156 | { |
7fcd7218 JH |
2157 | /* Avoid abnormal flags to leak from computed jumps turned |
2158 | into simplejumps. */ | |
f87c27b4 | 2159 | |
0e1638d4 | 2160 | e->flags &= ~EDGE_ABNORMAL; |
7fcd7218 | 2161 | |
5a566bed MM |
2162 | /* See if this edge is one we should keep. */ |
2163 | if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn)) | |
2164 | /* A conditional jump can fall through into the next | |
2165 | block, so we should keep the edge. */ | |
628f6a4e BE |
2166 | { |
2167 | ei_next (&ei); | |
2168 | continue; | |
2169 | } | |
5f0d2358 | 2170 | else if (e->dest != EXIT_BLOCK_PTR |
a813c111 | 2171 | && BB_HEAD (e->dest) == JUMP_LABEL (insn)) |
5a566bed MM |
2172 | /* If the destination block is the target of the jump, |
2173 | keep the edge. */ | |
628f6a4e BE |
2174 | { |
2175 | ei_next (&ei); | |
2176 | continue; | |
2177 | } | |
5a566bed MM |
2178 | else if (e->dest == EXIT_BLOCK_PTR && returnjump_p (insn)) |
2179 | /* If the destination block is the exit block, and this | |
2180 | instruction is a return, then keep the edge. */ | |
628f6a4e BE |
2181 | { |
2182 | ei_next (&ei); | |
2183 | continue; | |
2184 | } | |
5a566bed MM |
2185 | else if ((e->flags & EDGE_EH) && can_throw_internal (insn)) |
2186 | /* Keep the edges that correspond to exceptions thrown by | |
0b75beaa EB |
2187 | this instruction and rematerialize the EDGE_ABNORMAL |
2188 | flag we just cleared above. */ | |
2189 | { | |
2190 | e->flags |= EDGE_ABNORMAL; | |
628f6a4e | 2191 | ei_next (&ei); |
0b75beaa EB |
2192 | continue; |
2193 | } | |
5f0d2358 | 2194 | |
5a566bed | 2195 | /* We do not need this edge. */ |
c51d95ec | 2196 | bb->flags |= BB_DIRTY; |
ca6c03ca JH |
2197 | purged = true; |
2198 | remove_edge (e); | |
2199 | } | |
5f0d2358 | 2200 | |
628f6a4e | 2201 | if (EDGE_COUNT (bb->succs) == 0 || !purged) |
c51d95ec | 2202 | return purged; |
5f0d2358 | 2203 | |
c263766c RH |
2204 | if (dump_file) |
2205 | fprintf (dump_file, "Purged edges from bb %i\n", bb->index); | |
5f0d2358 | 2206 | |
ca6c03ca JH |
2207 | if (!optimize) |
2208 | return purged; | |
2209 | ||
2210 | /* Redistribute probabilities. */ | |
c5cbcccf | 2211 | if (single_succ_p (bb)) |
ca6c03ca | 2212 | { |
c5cbcccf ZD |
2213 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2214 | single_succ_edge (bb)->count = bb->count; | |
f87c27b4 | 2215 | } |
ca6c03ca JH |
2216 | else |
2217 | { | |
2218 | note = find_reg_note (insn, REG_BR_PROB, NULL); | |
2219 | if (!note) | |
2220 | return purged; | |
5f0d2358 | 2221 | |
ca6c03ca JH |
2222 | b = BRANCH_EDGE (bb); |
2223 | f = FALLTHRU_EDGE (bb); | |
2224 | b->probability = INTVAL (XEXP (note, 0)); | |
2225 | f->probability = REG_BR_PROB_BASE - b->probability; | |
2226 | b->count = bb->count * b->probability / REG_BR_PROB_BASE; | |
2227 | f->count = bb->count * f->probability / REG_BR_PROB_BASE; | |
2228 | } | |
5f0d2358 | 2229 | |
ca6c03ca JH |
2230 | return purged; |
2231 | } | |
4b4bf941 | 2232 | else if (CALL_P (insn) && SIBLING_CALL_P (insn)) |
1722c2c8 RH |
2233 | { |
2234 | /* First, there should not be any EH or ABCALL edges resulting | |
2235 | from non-local gotos and the like. If there were, we shouldn't | |
2236 | have created the sibcall in the first place. Second, there | |
2237 | should of course never have been a fallthru edge. */ | |
c5cbcccf ZD |
2238 | gcc_assert (single_succ_p (bb)); |
2239 | gcc_assert (single_succ_edge (bb)->flags | |
2240 | == (EDGE_SIBCALL | EDGE_ABNORMAL)); | |
1722c2c8 RH |
2241 | |
2242 | return 0; | |
2243 | } | |
ca6c03ca | 2244 | |
ca6c03ca JH |
2245 | /* If we don't see a jump insn, we don't know exactly why the block would |
2246 | have been broken at this point. Look for a simple, non-fallthru edge, | |
2247 | as these are only created by conditional branches. If we find such an | |
2248 | edge we know that there used to be a jump here and can then safely | |
2249 | remove all non-fallthru edges. */ | |
628f6a4e BE |
2250 | found = false; |
2251 | FOR_EACH_EDGE (e, ei, bb->succs) | |
2252 | if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU))) | |
2253 | { | |
2254 | found = true; | |
2255 | break; | |
2256 | } | |
5f0d2358 | 2257 | |
628f6a4e | 2258 | if (!found) |
ca6c03ca | 2259 | return purged; |
5f0d2358 | 2260 | |
2afa8dce DB |
2261 | /* Remove all but the fake and fallthru edges. The fake edge may be |
2262 | the only successor for this block in the case of noreturn | |
2263 | calls. */ | |
628f6a4e | 2264 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
ca6c03ca | 2265 | { |
2afa8dce | 2266 | if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE))) |
c51d95ec JH |
2267 | { |
2268 | bb->flags |= BB_DIRTY; | |
2269 | remove_edge (e); | |
2270 | purged = true; | |
2271 | } | |
628f6a4e BE |
2272 | else |
2273 | ei_next (&ei); | |
ca6c03ca | 2274 | } |
5f0d2358 | 2275 | |
c5cbcccf | 2276 | gcc_assert (single_succ_p (bb)); |
5f0d2358 | 2277 | |
c5cbcccf ZD |
2278 | single_succ_edge (bb)->probability = REG_BR_PROB_BASE; |
2279 | single_succ_edge (bb)->count = bb->count; | |
ca6c03ca | 2280 | |
c263766c RH |
2281 | if (dump_file) |
2282 | fprintf (dump_file, "Purged non-fallthru edges from bb %i\n", | |
0b17ab2f | 2283 | bb->index); |
ca6c03ca JH |
2284 | return purged; |
2285 | } | |
2286 | ||
5f0d2358 RK |
2287 | /* Search all basic blocks for potentially dead edges and purge them. Return |
2288 | true if some edge has been eliminated. */ | |
ca6c03ca JH |
2289 | |
2290 | bool | |
25cd19de | 2291 | purge_all_dead_edges (void) |
ca6c03ca | 2292 | { |
e0082a72 | 2293 | int purged = false; |
e0082a72 | 2294 | basic_block bb; |
473fb060 | 2295 | |
e0082a72 | 2296 | FOR_EACH_BB (bb) |
473fb060 | 2297 | { |
e0082a72 | 2298 | bool purged_here = purge_dead_edges (bb); |
5f0d2358 | 2299 | |
473fb060 | 2300 | purged |= purged_here; |
473fb060 | 2301 | } |
5f0d2358 | 2302 | |
ca6c03ca JH |
2303 | return purged; |
2304 | } | |
9ee634e3 JH |
2305 | |
2306 | /* Same as split_block but update cfg_layout structures. */ | |
f470c378 ZD |
2307 | |
2308 | static basic_block | |
d329e058 | 2309 | cfg_layout_split_block (basic_block bb, void *insnp) |
9ee634e3 JH |
2310 | { |
2311 | rtx insn = insnp; | |
f470c378 | 2312 | basic_block new_bb = rtl_split_block (bb, insn); |
9ee634e3 | 2313 | |
370369e1 JH |
2314 | new_bb->il.rtl->footer = bb->il.rtl->footer; |
2315 | bb->il.rtl->footer = NULL; | |
9ee634e3 | 2316 | |
f470c378 | 2317 | return new_bb; |
9ee634e3 JH |
2318 | } |
2319 | ||
2320 | ||
2321 | /* Redirect Edge to DEST. */ | |
6de9cd9a | 2322 | static edge |
d329e058 | 2323 | cfg_layout_redirect_edge_and_branch (edge e, basic_block dest) |
9ee634e3 JH |
2324 | { |
2325 | basic_block src = e->src; | |
6de9cd9a | 2326 | edge ret; |
9ee634e3 | 2327 | |
bc35512f | 2328 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
6de9cd9a | 2329 | return NULL; |
bc35512f | 2330 | |
3348b696 | 2331 | if (e->dest == dest) |
6de9cd9a | 2332 | return e; |
bc35512f | 2333 | |
3348b696 | 2334 | if (e->src != ENTRY_BLOCK_PTR |
6de9cd9a | 2335 | && (ret = try_redirect_by_replacing_jump (e, dest, true))) |
f345f21a JH |
2336 | { |
2337 | src->flags |= BB_DIRTY; | |
6de9cd9a | 2338 | return ret; |
f345f21a | 2339 | } |
bc35512f JH |
2340 | |
2341 | if (e->src == ENTRY_BLOCK_PTR | |
2342 | && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX)) | |
2343 | { | |
c263766c RH |
2344 | if (dump_file) |
2345 | fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n", | |
bc35512f JH |
2346 | e->src->index, dest->index); |
2347 | ||
f345f21a | 2348 | e->src->flags |= BB_DIRTY; |
bc35512f | 2349 | redirect_edge_succ (e, dest); |
6de9cd9a | 2350 | return e; |
bc35512f JH |
2351 | } |
2352 | ||
9ee634e3 JH |
2353 | /* Redirect_edge_and_branch may decide to turn branch into fallthru edge |
2354 | in the case the basic block appears to be in sequence. Avoid this | |
2355 | transformation. */ | |
2356 | ||
9ee634e3 JH |
2357 | if (e->flags & EDGE_FALLTHRU) |
2358 | { | |
2359 | /* Redirect any branch edges unified with the fallthru one. */ | |
4b4bf941 | 2360 | if (JUMP_P (BB_END (src)) |
432f982f JH |
2361 | && label_is_jump_target_p (BB_HEAD (e->dest), |
2362 | BB_END (src))) | |
9ee634e3 | 2363 | { |
341c100f | 2364 | edge redirected; |
c22cacf3 | 2365 | |
c263766c RH |
2366 | if (dump_file) |
2367 | fprintf (dump_file, "Fallthru edge unified with branch " | |
432f982f JH |
2368 | "%i->%i redirected to %i\n", |
2369 | e->src->index, e->dest->index, dest->index); | |
2370 | e->flags &= ~EDGE_FALLTHRU; | |
341c100f NS |
2371 | redirected = redirect_branch_edge (e, dest); |
2372 | gcc_assert (redirected); | |
432f982f | 2373 | e->flags |= EDGE_FALLTHRU; |
c22cacf3 | 2374 | e->src->flags |= BB_DIRTY; |
6de9cd9a | 2375 | return e; |
9ee634e3 JH |
2376 | } |
2377 | /* In case we are redirecting fallthru edge to the branch edge | |
c22cacf3 | 2378 | of conditional jump, remove it. */ |
628f6a4e | 2379 | if (EDGE_COUNT (src->succs) == 2) |
9ee634e3 | 2380 | { |
03101c6f KH |
2381 | /* Find the edge that is different from E. */ |
2382 | edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e); | |
628f6a4e | 2383 | |
9ee634e3 | 2384 | if (s->dest == dest |
a813c111 SB |
2385 | && any_condjump_p (BB_END (src)) |
2386 | && onlyjump_p (BB_END (src))) | |
2387 | delete_insn (BB_END (src)); | |
9ee634e3 | 2388 | } |
6de9cd9a | 2389 | ret = redirect_edge_succ_nodup (e, dest); |
c263766c RH |
2390 | if (dump_file) |
2391 | fprintf (dump_file, "Fallthru edge %i->%i redirected to %i\n", | |
bc35512f | 2392 | e->src->index, e->dest->index, dest->index); |
9ee634e3 JH |
2393 | } |
2394 | else | |
bc35512f | 2395 | ret = redirect_branch_edge (e, dest); |
9ee634e3 JH |
2396 | |
2397 | /* We don't want simplejumps in the insn stream during cfglayout. */ | |
341c100f | 2398 | gcc_assert (!simplejump_p (BB_END (src))); |
9ee634e3 | 2399 | |
f345f21a | 2400 | src->flags |= BB_DIRTY; |
9ee634e3 JH |
2401 | return ret; |
2402 | } | |
2403 | ||
2404 | /* Simple wrapper as we always can redirect fallthru edges. */ | |
2405 | static basic_block | |
d329e058 | 2406 | cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest) |
9ee634e3 | 2407 | { |
341c100f NS |
2408 | edge redirected = cfg_layout_redirect_edge_and_branch (e, dest); |
2409 | ||
2410 | gcc_assert (redirected); | |
9ee634e3 JH |
2411 | return NULL; |
2412 | } | |
2413 | ||
f470c378 ZD |
2414 | /* Same as delete_basic_block but update cfg_layout structures. */ |
2415 | ||
9ee634e3 | 2416 | static void |
d329e058 | 2417 | cfg_layout_delete_block (basic_block bb) |
9ee634e3 | 2418 | { |
a813c111 | 2419 | rtx insn, next, prev = PREV_INSN (BB_HEAD (bb)), *to, remaints; |
9ee634e3 | 2420 | |
370369e1 | 2421 | if (bb->il.rtl->header) |
9ee634e3 | 2422 | { |
a813c111 | 2423 | next = BB_HEAD (bb); |
9ee634e3 | 2424 | if (prev) |
370369e1 | 2425 | NEXT_INSN (prev) = bb->il.rtl->header; |
9ee634e3 | 2426 | else |
370369e1 JH |
2427 | set_first_insn (bb->il.rtl->header); |
2428 | PREV_INSN (bb->il.rtl->header) = prev; | |
2429 | insn = bb->il.rtl->header; | |
9ee634e3 JH |
2430 | while (NEXT_INSN (insn)) |
2431 | insn = NEXT_INSN (insn); | |
2432 | NEXT_INSN (insn) = next; | |
2433 | PREV_INSN (next) = insn; | |
2434 | } | |
a813c111 | 2435 | next = NEXT_INSN (BB_END (bb)); |
370369e1 | 2436 | if (bb->il.rtl->footer) |
9ee634e3 | 2437 | { |
370369e1 | 2438 | insn = bb->il.rtl->footer; |
bc35512f JH |
2439 | while (insn) |
2440 | { | |
4b4bf941 | 2441 | if (BARRIER_P (insn)) |
bc35512f JH |
2442 | { |
2443 | if (PREV_INSN (insn)) | |
2444 | NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn); | |
2445 | else | |
370369e1 | 2446 | bb->il.rtl->footer = NEXT_INSN (insn); |
bc35512f JH |
2447 | if (NEXT_INSN (insn)) |
2448 | PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn); | |
2449 | } | |
4b4bf941 | 2450 | if (LABEL_P (insn)) |
bc35512f JH |
2451 | break; |
2452 | insn = NEXT_INSN (insn); | |
2453 | } | |
370369e1 | 2454 | if (bb->il.rtl->footer) |
bc35512f | 2455 | { |
a813c111 | 2456 | insn = BB_END (bb); |
370369e1 JH |
2457 | NEXT_INSN (insn) = bb->il.rtl->footer; |
2458 | PREV_INSN (bb->il.rtl->footer) = insn; | |
bc35512f JH |
2459 | while (NEXT_INSN (insn)) |
2460 | insn = NEXT_INSN (insn); | |
2461 | NEXT_INSN (insn) = next; | |
2462 | if (next) | |
2463 | PREV_INSN (next) = insn; | |
2464 | else | |
2465 | set_last_insn (insn); | |
2466 | } | |
9ee634e3 JH |
2467 | } |
2468 | if (bb->next_bb != EXIT_BLOCK_PTR) | |
370369e1 | 2469 | to = &bb->next_bb->il.rtl->header; |
9ee634e3 JH |
2470 | else |
2471 | to = &cfg_layout_function_footer; | |
997de8ed | 2472 | |
9ee634e3 JH |
2473 | rtl_delete_block (bb); |
2474 | ||
2475 | if (prev) | |
2476 | prev = NEXT_INSN (prev); | |
d329e058 | 2477 | else |
9ee634e3 JH |
2478 | prev = get_insns (); |
2479 | if (next) | |
2480 | next = PREV_INSN (next); | |
d329e058 | 2481 | else |
9ee634e3 JH |
2482 | next = get_last_insn (); |
2483 | ||
2484 | if (next && NEXT_INSN (next) != prev) | |
2485 | { | |
2486 | remaints = unlink_insn_chain (prev, next); | |
2487 | insn = remaints; | |
2488 | while (NEXT_INSN (insn)) | |
2489 | insn = NEXT_INSN (insn); | |
2490 | NEXT_INSN (insn) = *to; | |
2491 | if (*to) | |
2492 | PREV_INSN (*to) = insn; | |
2493 | *to = remaints; | |
2494 | } | |
2495 | } | |
2496 | ||
beb235f8 | 2497 | /* Return true when blocks A and B can be safely merged. */ |
bc35512f JH |
2498 | static bool |
2499 | cfg_layout_can_merge_blocks_p (basic_block a, basic_block b) | |
2500 | { | |
750054a2 CT |
2501 | /* If we are partitioning hot/cold basic blocks, we don't want to |
2502 | mess up unconditional or indirect jumps that cross between hot | |
076c7ab8 ZW |
2503 | and cold sections. |
2504 | ||
8e8d5162 | 2505 | Basic block partitioning may result in some jumps that appear to |
c22cacf3 MS |
2506 | be optimizable (or blocks that appear to be mergeable), but which really |
2507 | must be left untouched (they are required to make it safely across | |
2508 | partition boundaries). See the comments at the top of | |
8e8d5162 CT |
2509 | bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ |
2510 | ||
87c8b4be | 2511 | if (BB_PARTITION (a) != BB_PARTITION (b)) |
076c7ab8 | 2512 | return false; |
750054a2 | 2513 | |
bc35512f | 2514 | /* There must be exactly one edge in between the blocks. */ |
c5cbcccf ZD |
2515 | return (single_succ_p (a) |
2516 | && single_succ (a) == b | |
2517 | && single_pred_p (b) == 1 | |
628f6a4e | 2518 | && a != b |
bc35512f | 2519 | /* Must be simple edge. */ |
c5cbcccf | 2520 | && !(single_succ_edge (a)->flags & EDGE_COMPLEX) |
bc35512f JH |
2521 | && a != ENTRY_BLOCK_PTR && b != EXIT_BLOCK_PTR |
2522 | /* If the jump insn has side effects, | |
2523 | we can't kill the edge. */ | |
4b4bf941 | 2524 | && (!JUMP_P (BB_END (a)) |
e24e7211 | 2525 | || (reload_completed |
a813c111 | 2526 | ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a))))); |
bc35512f JH |
2527 | } |
2528 | ||
41806d92 NS |
2529 | /* Merge block A and B. The blocks must be mergeable. */ |
2530 | ||
bc35512f JH |
2531 | static void |
2532 | cfg_layout_merge_blocks (basic_block a, basic_block b) | |
2533 | { | |
2534 | #ifdef ENABLE_CHECKING | |
341c100f | 2535 | gcc_assert (cfg_layout_can_merge_blocks_p (a, b)); |
bc35512f JH |
2536 | #endif |
2537 | ||
2538 | /* If there was a CODE_LABEL beginning B, delete it. */ | |
4b4bf941 | 2539 | if (LABEL_P (BB_HEAD (b))) |
2c97f8e4 RH |
2540 | { |
2541 | /* This might have been an EH label that no longer has incoming | |
2542 | EH edges. Update data structures to match. */ | |
2543 | maybe_remove_eh_handler (BB_HEAD (b)); | |
c22cacf3 | 2544 | |
2c97f8e4 RH |
2545 | delete_insn (BB_HEAD (b)); |
2546 | } | |
bc35512f JH |
2547 | |
2548 | /* We should have fallthru edge in a, or we can do dummy redirection to get | |
2549 | it cleaned up. */ | |
4b4bf941 | 2550 | if (JUMP_P (BB_END (a))) |
628f6a4e | 2551 | try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true); |
341c100f | 2552 | gcc_assert (!JUMP_P (BB_END (a))); |
bc35512f JH |
2553 | |
2554 | /* Possible line number notes should appear in between. */ | |
370369e1 | 2555 | if (b->il.rtl->header) |
bc35512f | 2556 | { |
a813c111 | 2557 | rtx first = BB_END (a), last; |
bc35512f | 2558 | |
370369e1 | 2559 | last = emit_insn_after_noloc (b->il.rtl->header, BB_END (a)); |
bc35512f | 2560 | delete_insn_chain (NEXT_INSN (first), last); |
370369e1 | 2561 | b->il.rtl->header = NULL; |
bc35512f JH |
2562 | } |
2563 | ||
2564 | /* In the case basic blocks are not adjacent, move them around. */ | |
a813c111 | 2565 | if (NEXT_INSN (BB_END (a)) != BB_HEAD (b)) |
bc35512f | 2566 | { |
a813c111 | 2567 | rtx first = unlink_insn_chain (BB_HEAD (b), BB_END (b)); |
bc35512f | 2568 | |
a7102479 | 2569 | emit_insn_after_noloc (first, BB_END (a)); |
bc35512f JH |
2570 | /* Skip possible DELETED_LABEL insn. */ |
2571 | if (!NOTE_INSN_BASIC_BLOCK_P (first)) | |
2572 | first = NEXT_INSN (first); | |
341c100f | 2573 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (first)); |
a813c111 | 2574 | BB_HEAD (b) = NULL; |
bc35512f JH |
2575 | delete_insn (first); |
2576 | } | |
2577 | /* Otherwise just re-associate the instructions. */ | |
2578 | else | |
2579 | { | |
2580 | rtx insn; | |
2581 | ||
a813c111 SB |
2582 | for (insn = BB_HEAD (b); |
2583 | insn != NEXT_INSN (BB_END (b)); | |
2584 | insn = NEXT_INSN (insn)) | |
bc35512f | 2585 | set_block_for_insn (insn, a); |
a813c111 | 2586 | insn = BB_HEAD (b); |
bc35512f JH |
2587 | /* Skip possible DELETED_LABEL insn. */ |
2588 | if (!NOTE_INSN_BASIC_BLOCK_P (insn)) | |
2589 | insn = NEXT_INSN (insn); | |
341c100f | 2590 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn)); |
a813c111 SB |
2591 | BB_HEAD (b) = NULL; |
2592 | BB_END (a) = BB_END (b); | |
bc35512f JH |
2593 | delete_insn (insn); |
2594 | } | |
2595 | ||
2596 | /* Possible tablejumps and barriers should appear after the block. */ | |
370369e1 | 2597 | if (b->il.rtl->footer) |
bc35512f | 2598 | { |
370369e1 JH |
2599 | if (!a->il.rtl->footer) |
2600 | a->il.rtl->footer = b->il.rtl->footer; | |
bc35512f JH |
2601 | else |
2602 | { | |
370369e1 | 2603 | rtx last = a->il.rtl->footer; |
bc35512f JH |
2604 | |
2605 | while (NEXT_INSN (last)) | |
2606 | last = NEXT_INSN (last); | |
370369e1 JH |
2607 | NEXT_INSN (last) = b->il.rtl->footer; |
2608 | PREV_INSN (b->il.rtl->footer) = last; | |
bc35512f | 2609 | } |
370369e1 | 2610 | b->il.rtl->footer = NULL; |
bc35512f | 2611 | } |
5e2d947c | 2612 | a->il.rtl->global_live_at_end = b->il.rtl->global_live_at_end; |
bc35512f | 2613 | |
c263766c RH |
2614 | if (dump_file) |
2615 | fprintf (dump_file, "Merged blocks %d and %d.\n", | |
bc35512f | 2616 | a->index, b->index); |
bc35512f JH |
2617 | } |
2618 | ||
2619 | /* Split edge E. */ | |
f470c378 | 2620 | |
bc35512f JH |
2621 | static basic_block |
2622 | cfg_layout_split_edge (edge e) | |
2623 | { | |
bc35512f JH |
2624 | basic_block new_bb = |
2625 | create_basic_block (e->src != ENTRY_BLOCK_PTR | |
a813c111 | 2626 | ? NEXT_INSN (BB_END (e->src)) : get_insns (), |
bc35512f JH |
2627 | NULL_RTX, e->src); |
2628 | ||
af874237 JW |
2629 | /* ??? This info is likely going to be out of date very soon, but we must |
2630 | create it to avoid getting an ICE later. */ | |
5e2d947c | 2631 | if (e->dest->il.rtl->global_live_at_start) |
af874237 | 2632 | { |
5e2d947c JH |
2633 | new_bb->il.rtl->global_live_at_start = ALLOC_REG_SET (®_obstack); |
2634 | new_bb->il.rtl->global_live_at_end = ALLOC_REG_SET (®_obstack); | |
2635 | COPY_REG_SET (new_bb->il.rtl->global_live_at_start, | |
2636 | e->dest->il.rtl->global_live_at_start); | |
2637 | COPY_REG_SET (new_bb->il.rtl->global_live_at_end, | |
2638 | e->dest->il.rtl->global_live_at_start); | |
af874237 JW |
2639 | } |
2640 | ||
a9b2ee88 | 2641 | make_edge (new_bb, e->dest, EDGE_FALLTHRU); |
bc35512f JH |
2642 | redirect_edge_and_branch_force (e, new_bb); |
2643 | ||
2644 | return new_bb; | |
2645 | } | |
2646 | ||
f470c378 ZD |
2647 | /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */ |
2648 | ||
2649 | static void | |
2650 | rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED) | |
2651 | { | |
2652 | } | |
2653 | ||
6de9cd9a DN |
2654 | /* Return 1 if BB ends with a call, possibly followed by some |
2655 | instructions that must stay with the call, 0 otherwise. */ | |
2656 | ||
2657 | static bool | |
2658 | rtl_block_ends_with_call_p (basic_block bb) | |
2659 | { | |
2660 | rtx insn = BB_END (bb); | |
2661 | ||
4b4bf941 | 2662 | while (!CALL_P (insn) |
6de9cd9a DN |
2663 | && insn != BB_HEAD (bb) |
2664 | && keep_with_call_p (insn)) | |
2665 | insn = PREV_INSN (insn); | |
4b4bf941 | 2666 | return (CALL_P (insn)); |
6de9cd9a DN |
2667 | } |
2668 | ||
2669 | /* Return 1 if BB ends with a conditional branch, 0 otherwise. */ | |
2670 | ||
2671 | static bool | |
2672 | rtl_block_ends_with_condjump_p (basic_block bb) | |
2673 | { | |
2674 | return any_condjump_p (BB_END (bb)); | |
2675 | } | |
2676 | ||
2677 | /* Return true if we need to add fake edge to exit. | |
2678 | Helper function for rtl_flow_call_edges_add. */ | |
2679 | ||
2680 | static bool | |
2681 | need_fake_edge_p (rtx insn) | |
2682 | { | |
2683 | if (!INSN_P (insn)) | |
2684 | return false; | |
2685 | ||
4b4bf941 | 2686 | if ((CALL_P (insn) |
6de9cd9a DN |
2687 | && !SIBLING_CALL_P (insn) |
2688 | && !find_reg_note (insn, REG_NORETURN, NULL) | |
6de9cd9a DN |
2689 | && !CONST_OR_PURE_CALL_P (insn))) |
2690 | return true; | |
2691 | ||
2692 | return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS | |
2693 | && MEM_VOLATILE_P (PATTERN (insn))) | |
2694 | || (GET_CODE (PATTERN (insn)) == PARALLEL | |
2695 | && asm_noperands (insn) != -1 | |
2696 | && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0))) | |
2697 | || GET_CODE (PATTERN (insn)) == ASM_INPUT); | |
2698 | } | |
2699 | ||
2700 | /* Add fake edges to the function exit for any non constant and non noreturn | |
2701 | calls, volatile inline assembly in the bitmap of blocks specified by | |
2702 | BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks | |
2703 | that were split. | |
2704 | ||
2705 | The goal is to expose cases in which entering a basic block does not imply | |
2706 | that all subsequent instructions must be executed. */ | |
2707 | ||
2708 | static int | |
2709 | rtl_flow_call_edges_add (sbitmap blocks) | |
2710 | { | |
2711 | int i; | |
2712 | int blocks_split = 0; | |
2713 | int last_bb = last_basic_block; | |
2714 | bool check_last_block = false; | |
2715 | ||
24bd1a0b | 2716 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
6de9cd9a DN |
2717 | return 0; |
2718 | ||
2719 | if (! blocks) | |
2720 | check_last_block = true; | |
2721 | else | |
2722 | check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index); | |
2723 | ||
2724 | /* In the last basic block, before epilogue generation, there will be | |
2725 | a fallthru edge to EXIT. Special care is required if the last insn | |
2726 | of the last basic block is a call because make_edge folds duplicate | |
2727 | edges, which would result in the fallthru edge also being marked | |
2728 | fake, which would result in the fallthru edge being removed by | |
2729 | remove_fake_edges, which would result in an invalid CFG. | |
2730 | ||
2731 | Moreover, we can't elide the outgoing fake edge, since the block | |
2732 | profiler needs to take this into account in order to solve the minimal | |
2733 | spanning tree in the case that the call doesn't return. | |
2734 | ||
2735 | Handle this by adding a dummy instruction in a new last basic block. */ | |
2736 | if (check_last_block) | |
2737 | { | |
2738 | basic_block bb = EXIT_BLOCK_PTR->prev_bb; | |
2739 | rtx insn = BB_END (bb); | |
2740 | ||
2741 | /* Back up past insns that must be kept in the same block as a call. */ | |
2742 | while (insn != BB_HEAD (bb) | |
2743 | && keep_with_call_p (insn)) | |
2744 | insn = PREV_INSN (insn); | |
2745 | ||
2746 | if (need_fake_edge_p (insn)) | |
2747 | { | |
2748 | edge e; | |
2749 | ||
9ff3d2de JL |
2750 | e = find_edge (bb, EXIT_BLOCK_PTR); |
2751 | if (e) | |
2752 | { | |
2753 | insert_insn_on_edge (gen_rtx_USE (VOIDmode, const0_rtx), e); | |
2754 | commit_edge_insertions (); | |
2755 | } | |
6de9cd9a DN |
2756 | } |
2757 | } | |
2758 | ||
2759 | /* Now add fake edges to the function exit for any non constant | |
2760 | calls since there is no way that we can determine if they will | |
2761 | return or not... */ | |
2762 | ||
24bd1a0b | 2763 | for (i = NUM_FIXED_BLOCKS; i < last_bb; i++) |
6de9cd9a DN |
2764 | { |
2765 | basic_block bb = BASIC_BLOCK (i); | |
2766 | rtx insn; | |
2767 | rtx prev_insn; | |
2768 | ||
2769 | if (!bb) | |
2770 | continue; | |
2771 | ||
2772 | if (blocks && !TEST_BIT (blocks, i)) | |
2773 | continue; | |
2774 | ||
2775 | for (insn = BB_END (bb); ; insn = prev_insn) | |
2776 | { | |
2777 | prev_insn = PREV_INSN (insn); | |
2778 | if (need_fake_edge_p (insn)) | |
2779 | { | |
2780 | edge e; | |
2781 | rtx split_at_insn = insn; | |
2782 | ||
2783 | /* Don't split the block between a call and an insn that should | |
c22cacf3 | 2784 | remain in the same block as the call. */ |
4b4bf941 | 2785 | if (CALL_P (insn)) |
6de9cd9a DN |
2786 | while (split_at_insn != BB_END (bb) |
2787 | && keep_with_call_p (NEXT_INSN (split_at_insn))) | |
2788 | split_at_insn = NEXT_INSN (split_at_insn); | |
2789 | ||
2790 | /* The handling above of the final block before the epilogue | |
c22cacf3 | 2791 | should be enough to verify that there is no edge to the exit |
6de9cd9a DN |
2792 | block in CFG already. Calling make_edge in such case would |
2793 | cause us to mark that edge as fake and remove it later. */ | |
2794 | ||
2795 | #ifdef ENABLE_CHECKING | |
2796 | if (split_at_insn == BB_END (bb)) | |
628f6a4e | 2797 | { |
9ff3d2de JL |
2798 | e = find_edge (bb, EXIT_BLOCK_PTR); |
2799 | gcc_assert (e == NULL); | |
628f6a4e | 2800 | } |
6de9cd9a DN |
2801 | #endif |
2802 | ||
2803 | /* Note that the following may create a new basic block | |
2804 | and renumber the existing basic blocks. */ | |
2805 | if (split_at_insn != BB_END (bb)) | |
2806 | { | |
2807 | e = split_block (bb, split_at_insn); | |
2808 | if (e) | |
2809 | blocks_split++; | |
2810 | } | |
2811 | ||
2812 | make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE); | |
2813 | } | |
2814 | ||
2815 | if (insn == BB_HEAD (bb)) | |
2816 | break; | |
2817 | } | |
2818 | } | |
2819 | ||
2820 | if (blocks_split) | |
2821 | verify_flow_info (); | |
2822 | ||
2823 | return blocks_split; | |
2824 | } | |
2825 | ||
1cb7dfc3 | 2826 | /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is |
315682fb | 2827 | the conditional branch target, SECOND_HEAD should be the fall-thru |
1cb7dfc3 MH |
2828 | there is no need to handle this here the loop versioning code handles |
2829 | this. the reason for SECON_HEAD is that it is needed for condition | |
2830 | in trees, and this should be of the same type since it is a hook. */ | |
2831 | static void | |
2832 | rtl_lv_add_condition_to_bb (basic_block first_head , | |
c22cacf3 MS |
2833 | basic_block second_head ATTRIBUTE_UNUSED, |
2834 | basic_block cond_bb, void *comp_rtx) | |
1cb7dfc3 MH |
2835 | { |
2836 | rtx label, seq, jump; | |
2837 | rtx op0 = XEXP ((rtx)comp_rtx, 0); | |
2838 | rtx op1 = XEXP ((rtx)comp_rtx, 1); | |
2839 | enum rtx_code comp = GET_CODE ((rtx)comp_rtx); | |
2840 | enum machine_mode mode; | |
2841 | ||
2842 | ||
2843 | label = block_label (first_head); | |
2844 | mode = GET_MODE (op0); | |
2845 | if (mode == VOIDmode) | |
2846 | mode = GET_MODE (op1); | |
2847 | ||
2848 | start_sequence (); | |
2849 | op0 = force_operand (op0, NULL_RTX); | |
2850 | op1 = force_operand (op1, NULL_RTX); | |
2851 | do_compare_rtx_and_jump (op0, op1, comp, 0, | |
2852 | mode, NULL_RTX, NULL_RTX, label); | |
2853 | jump = get_last_insn (); | |
2854 | JUMP_LABEL (jump) = label; | |
2855 | LABEL_NUSES (label)++; | |
2856 | seq = get_insns (); | |
2857 | end_sequence (); | |
2858 | ||
2859 | /* Add the new cond , in the new head. */ | |
2860 | emit_insn_after(seq, BB_END(cond_bb)); | |
2861 | } | |
2862 | ||
2863 | ||
2864 | /* Given a block B with unconditional branch at its end, get the | |
2865 | store the return the branch edge and the fall-thru edge in | |
2866 | BRANCH_EDGE and FALLTHRU_EDGE respectively. */ | |
2867 | static void | |
2868 | rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge, | |
2869 | edge *fallthru_edge) | |
2870 | { | |
2871 | edge e = EDGE_SUCC (b, 0); | |
2872 | ||
2873 | if (e->flags & EDGE_FALLTHRU) | |
2874 | { | |
2875 | *fallthru_edge = e; | |
2876 | *branch_edge = EDGE_SUCC (b, 1); | |
2877 | } | |
2878 | else | |
2879 | { | |
2880 | *branch_edge = e; | |
2881 | *fallthru_edge = EDGE_SUCC (b, 1); | |
2882 | } | |
2883 | } | |
2884 | ||
5e2d947c JH |
2885 | void |
2886 | init_rtl_bb_info (basic_block bb) | |
2887 | { | |
2888 | gcc_assert (!bb->il.rtl); | |
2889 | bb->il.rtl = ggc_alloc_cleared (sizeof (struct rtl_bb_info)); | |
2890 | } | |
2891 | ||
1cb7dfc3 | 2892 | |
8cd37d0b RL |
2893 | /* Add EXPR to the end of basic block BB. */ |
2894 | ||
2895 | rtx | |
2896 | insert_insn_end_bb_new (rtx pat, basic_block bb) | |
2897 | { | |
2898 | rtx insn = BB_END (bb); | |
2899 | rtx new_insn; | |
2900 | rtx pat_end = pat; | |
2901 | ||
2902 | while (NEXT_INSN (pat_end) != NULL_RTX) | |
2903 | pat_end = NEXT_INSN (pat_end); | |
2904 | ||
2905 | /* If the last insn is a jump, insert EXPR in front [taking care to | |
2906 | handle cc0, etc. properly]. Similarly we need to care trapping | |
2907 | instructions in presence of non-call exceptions. */ | |
2908 | ||
2909 | if (JUMP_P (insn) | |
2910 | || (NONJUMP_INSN_P (insn) | |
2911 | && (!single_succ_p (bb) | |
2912 | || single_succ_edge (bb)->flags & EDGE_ABNORMAL))) | |
2913 | { | |
2914 | #ifdef HAVE_cc0 | |
2915 | rtx note; | |
2916 | #endif | |
2917 | /* If this is a jump table, then we can't insert stuff here. Since | |
2918 | we know the previous real insn must be the tablejump, we insert | |
2919 | the new instruction just before the tablejump. */ | |
2920 | if (GET_CODE (PATTERN (insn)) == ADDR_VEC | |
2921 | || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC) | |
2922 | insn = prev_real_insn (insn); | |
2923 | ||
2924 | #ifdef HAVE_cc0 | |
2925 | /* FIXME: 'twould be nice to call prev_cc0_setter here but it aborts | |
2926 | if cc0 isn't set. */ | |
2927 | note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX); | |
2928 | if (note) | |
2929 | insn = XEXP (note, 0); | |
2930 | else | |
2931 | { | |
2932 | rtx maybe_cc0_setter = prev_nonnote_insn (insn); | |
2933 | if (maybe_cc0_setter | |
2934 | && INSN_P (maybe_cc0_setter) | |
2935 | && sets_cc0_p (PATTERN (maybe_cc0_setter))) | |
2936 | insn = maybe_cc0_setter; | |
2937 | } | |
2938 | #endif | |
2939 | /* FIXME: What if something in cc0/jump uses value set in new | |
2940 | insn? */ | |
2941 | new_insn = emit_insn_before_noloc (pat, insn); | |
2942 | } | |
2943 | ||
2944 | /* Likewise if the last insn is a call, as will happen in the presence | |
2945 | of exception handling. */ | |
2946 | else if (CALL_P (insn) | |
2947 | && (!single_succ_p (bb) | |
2948 | || single_succ_edge (bb)->flags & EDGE_ABNORMAL)) | |
2949 | { | |
2950 | /* Keeping in mind SMALL_REGISTER_CLASSES and parameters in registers, | |
2951 | we search backward and place the instructions before the first | |
2952 | parameter is loaded. Do this for everyone for consistency and a | |
2953 | presumption that we'll get better code elsewhere as well. */ | |
2954 | ||
2955 | /* Since different machines initialize their parameter registers | |
2956 | in different orders, assume nothing. Collect the set of all | |
2957 | parameter registers. */ | |
2958 | insn = find_first_parameter_load (insn, BB_HEAD (bb)); | |
2959 | ||
2960 | /* If we found all the parameter loads, then we want to insert | |
2961 | before the first parameter load. | |
2962 | ||
2963 | If we did not find all the parameter loads, then we might have | |
2964 | stopped on the head of the block, which could be a CODE_LABEL. | |
2965 | If we inserted before the CODE_LABEL, then we would be putting | |
2966 | the insn in the wrong basic block. In that case, put the insn | |
2967 | after the CODE_LABEL. Also, respect NOTE_INSN_BASIC_BLOCK. */ | |
2968 | while (LABEL_P (insn) | |
2969 | || NOTE_INSN_BASIC_BLOCK_P (insn)) | |
2970 | insn = NEXT_INSN (insn); | |
2971 | ||
2972 | new_insn = emit_insn_before_noloc (pat, insn); | |
2973 | } | |
2974 | else | |
2975 | new_insn = emit_insn_after_noloc (pat, insn); | |
2976 | ||
2977 | return new_insn; | |
2978 | } | |
2979 | ||
9ee634e3 JH |
2980 | /* Implementation of CFG manipulation for linearized RTL. */ |
2981 | struct cfg_hooks rtl_cfg_hooks = { | |
f470c378 | 2982 | "rtl", |
9ee634e3 | 2983 | rtl_verify_flow_info, |
10e9fecc | 2984 | rtl_dump_bb, |
bc35512f | 2985 | rtl_create_basic_block, |
9ee634e3 JH |
2986 | rtl_redirect_edge_and_branch, |
2987 | rtl_redirect_edge_and_branch_force, | |
2988 | rtl_delete_block, | |
2989 | rtl_split_block, | |
f470c378 | 2990 | rtl_move_block_after, |
bc35512f JH |
2991 | rtl_can_merge_blocks, /* can_merge_blocks_p */ |
2992 | rtl_merge_blocks, | |
6de9cd9a DN |
2993 | rtl_predict_edge, |
2994 | rtl_predicted_by_p, | |
2995 | NULL, /* can_duplicate_block_p */ | |
2996 | NULL, /* duplicate_block */ | |
f470c378 ZD |
2997 | rtl_split_edge, |
2998 | rtl_make_forwarder_block, | |
6de9cd9a DN |
2999 | rtl_tidy_fallthru_edge, |
3000 | rtl_block_ends_with_call_p, | |
3001 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
3002 | rtl_flow_call_edges_add, |
3003 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
3004 | NULL, /* execute_on_shrinking_pred */ |
3005 | NULL, /* duplicate loop for trees */ | |
3006 | NULL, /* lv_add_condition_to_bb */ | |
3007 | NULL, /* lv_adjust_loop_header_phi*/ | |
3008 | NULL, /* extract_cond_bb_edges */ | |
c22cacf3 | 3009 | NULL /* flush_pending_stmts */ |
9ee634e3 JH |
3010 | }; |
3011 | ||
3012 | /* Implementation of CFG manipulation for cfg layout RTL, where | |
3013 | basic block connected via fallthru edges does not have to be adjacent. | |
3014 | This representation will hopefully become the default one in future | |
3015 | version of the compiler. */ | |
6de9cd9a DN |
3016 | |
3017 | /* We do not want to declare these functions in a header file, since they | |
3018 | should only be used through the cfghooks interface, and we do not want to | |
3019 | move them here since it would require also moving quite a lot of related | |
3020 | code. */ | |
3021 | extern bool cfg_layout_can_duplicate_bb_p (basic_block); | |
3022 | extern basic_block cfg_layout_duplicate_bb (basic_block); | |
3023 | ||
9ee634e3 | 3024 | struct cfg_hooks cfg_layout_rtl_cfg_hooks = { |
f470c378 | 3025 | "cfglayout mode", |
bc35512f | 3026 | rtl_verify_flow_info_1, |
10e9fecc | 3027 | rtl_dump_bb, |
bc35512f | 3028 | cfg_layout_create_basic_block, |
9ee634e3 JH |
3029 | cfg_layout_redirect_edge_and_branch, |
3030 | cfg_layout_redirect_edge_and_branch_force, | |
3031 | cfg_layout_delete_block, | |
3032 | cfg_layout_split_block, | |
f470c378 | 3033 | rtl_move_block_after, |
bc35512f JH |
3034 | cfg_layout_can_merge_blocks_p, |
3035 | cfg_layout_merge_blocks, | |
6de9cd9a DN |
3036 | rtl_predict_edge, |
3037 | rtl_predicted_by_p, | |
3038 | cfg_layout_can_duplicate_bb_p, | |
3039 | cfg_layout_duplicate_bb, | |
f470c378 ZD |
3040 | cfg_layout_split_edge, |
3041 | rtl_make_forwarder_block, | |
6de9cd9a DN |
3042 | NULL, |
3043 | rtl_block_ends_with_call_p, | |
3044 | rtl_block_ends_with_condjump_p, | |
d9d4706f KH |
3045 | rtl_flow_call_edges_add, |
3046 | NULL, /* execute_on_growing_pred */ | |
1cb7dfc3 MH |
3047 | NULL, /* execute_on_shrinking_pred */ |
3048 | duplicate_loop_to_header_edge, /* duplicate loop for trees */ | |
3049 | rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */ | |
3050 | NULL, /* lv_adjust_loop_header_phi*/ | |
3051 | rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */ | |
c22cacf3 | 3052 | NULL /* flush_pending_stmts */ |
9ee634e3 | 3053 | }; |