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9ca8d59e | 1 | /* Generic partial redundancy elimination with lazy code motion support. |
711789cc | 2 | Copyright (C) 1998-2013 Free Software Foundation, Inc. |
e48ba7af | 3 | |
f12b58b3 | 4 | This file is part of GCC. |
e48ba7af | 5 | |
f12b58b3 | 6 | GCC is free software; you can redistribute it and/or modify it under |
7 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 8 | Software Foundation; either version 3, or (at your option) any later |
f12b58b3 | 9 | version. |
e48ba7af | 10 | |
f12b58b3 | 11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
e48ba7af | 15 | |
16 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
e48ba7af | 19 | |
20 | /* These routines are meant to be used by various optimization | |
5ab08585 | 21 | passes which can be modeled as lazy code motion problems. |
e48ba7af | 22 | Including, but not limited to: |
23 | ||
24 | * Traditional partial redundancy elimination. | |
25 | ||
26 | * Placement of caller/caller register save/restores. | |
27 | ||
28 | * Load/store motion. | |
29 | ||
30 | * Copy motion. | |
31 | ||
32 | * Conversion of flat register files to a stacked register | |
33 | model. | |
34 | ||
35 | * Dead load/store elimination. | |
36 | ||
37 | These routines accept as input: | |
38 | ||
39 | * Basic block information (number of blocks, lists of | |
40 | predecessors and successors). Note the granularity | |
41 | does not need to be basic block, they could be statements | |
42 | or functions. | |
43 | ||
44 | * Bitmaps of local properties (computed, transparent and | |
45 | anticipatable expressions). | |
46 | ||
47 | The output of these routines is bitmap of redundant computations | |
48 | and a bitmap of optimal placement points. */ | |
49 | ||
50 | ||
51 | #include "config.h" | |
52 | #include "system.h" | |
805e22b2 | 53 | #include "coretypes.h" |
54 | #include "tm.h" | |
e48ba7af | 55 | #include "rtl.h" |
56 | #include "regs.h" | |
57 | #include "hard-reg-set.h" | |
58 | #include "flags.h" | |
e48ba7af | 59 | #include "insn-config.h" |
60 | #include "recog.h" | |
61 | #include "basic-block.h" | |
18862b5a | 62 | #include "tm_p.h" |
6ce54148 | 63 | #include "function.h" |
0f71a633 | 64 | #include "sbitmap.h" |
b9ed1410 | 65 | #include "dumpfile.h" |
e48ba7af | 66 | |
7bcd381b | 67 | /* Edge based LCM routines. */ |
3ad4992f | 68 | static void compute_antinout_edge (sbitmap *, sbitmap *, sbitmap *, sbitmap *); |
69 | static void compute_earliest (struct edge_list *, int, sbitmap *, sbitmap *, | |
70 | sbitmap *, sbitmap *, sbitmap *); | |
71 | static void compute_laterin (struct edge_list *, sbitmap *, sbitmap *, | |
72 | sbitmap *, sbitmap *); | |
73 | static void compute_insert_delete (struct edge_list *edge_list, sbitmap *, | |
74 | sbitmap *, sbitmap *, sbitmap *, sbitmap *); | |
7bcd381b | 75 | |
76 | /* Edge based LCM routines on a reverse flowgraph. */ | |
3ad4992f | 77 | static void compute_farthest (struct edge_list *, int, sbitmap *, sbitmap *, |
78 | sbitmap*, sbitmap *, sbitmap *); | |
79 | static void compute_nearerout (struct edge_list *, sbitmap *, sbitmap *, | |
80 | sbitmap *, sbitmap *); | |
81 | static void compute_rev_insert_delete (struct edge_list *edge_list, sbitmap *, | |
82 | sbitmap *, sbitmap *, sbitmap *, | |
83 | sbitmap *); | |
7bcd381b | 84 | \f |
85 | /* Edge based lcm routines. */ | |
3b7e1f27 | 86 | |
5ab08585 | 87 | /* Compute expression anticipatability at entrance and exit of each block. |
88 | This is done based on the flow graph, and not on the pred-succ lists. | |
7bcd381b | 89 | Other than that, its pretty much identical to compute_antinout. */ |
e48ba7af | 90 | |
91 | static void | |
3ad4992f | 92 | compute_antinout_edge (sbitmap *antloc, sbitmap *transp, sbitmap *antin, |
93 | sbitmap *antout) | |
e48ba7af | 94 | { |
4c26117a | 95 | basic_block bb; |
7bcd381b | 96 | edge e; |
2c59145b | 97 | basic_block *worklist, *qin, *qout, *qend; |
98 | unsigned int qlen; | |
cd665a06 | 99 | edge_iterator ei; |
3b7e1f27 | 100 | |
2325f0e2 | 101 | /* Allocate a worklist array/queue. Entries are only added to the |
102 | list if they were not already on the list. So the size is | |
103 | bounded by the number of basic blocks. */ | |
a28770e1 | 104 | qin = qout = worklist = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun)); |
e48ba7af | 105 | |
2325f0e2 | 106 | /* We want a maximal solution, so make an optimistic initialization of |
107 | ANTIN. */ | |
53c5d9d4 | 108 | bitmap_vector_ones (antin, last_basic_block); |
e48ba7af | 109 | |
5d6931e2 | 110 | /* Put every block on the worklist; this is necessary because of the |
111 | optimistic initialization of ANTIN above. */ | |
4c26117a | 112 | FOR_EACH_BB_REVERSE (bb) |
e48ba7af | 113 | { |
ea0041f4 | 114 | *qin++ = bb; |
4c26117a | 115 | bb->aux = bb; |
2325f0e2 | 116 | } |
5ab08585 | 117 | |
2c59145b | 118 | qin = worklist; |
a28770e1 | 119 | qend = &worklist[n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS]; |
120 | qlen = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; | |
e48ba7af | 121 | |
5d6931e2 | 122 | /* Mark blocks which are predecessors of the exit block so that we |
123 | can easily identify them below. */ | |
cd665a06 | 124 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
5d6931e2 | 125 | e->src->aux = EXIT_BLOCK_PTR; |
126 | ||
2325f0e2 | 127 | /* Iterate until the worklist is empty. */ |
2c59145b | 128 | while (qlen) |
2325f0e2 | 129 | { |
130 | /* Take the first entry off the worklist. */ | |
4c26117a | 131 | bb = *qout++; |
2c59145b | 132 | qlen--; |
3b7e1f27 | 133 | |
2c59145b | 134 | if (qout >= qend) |
8851e806 | 135 | qout = worklist; |
e48ba7af | 136 | |
4c26117a | 137 | if (bb->aux == EXIT_BLOCK_PTR) |
9ca8d59e | 138 | /* Do not clear the aux field for blocks which are predecessors of |
139 | the EXIT block. That way we never add then to the worklist | |
140 | again. */ | |
53c5d9d4 | 141 | bitmap_clear (antout[bb->index]); |
2325f0e2 | 142 | else |
143 | { | |
144 | /* Clear the aux field of this block so that it can be added to | |
145 | the worklist again if necessary. */ | |
4c26117a | 146 | bb->aux = NULL; |
08b7917c | 147 | bitmap_intersection_of_succs (antout[bb->index], antin, bb); |
2325f0e2 | 148 | } |
7bcd381b | 149 | |
53c5d9d4 | 150 | if (bitmap_or_and (antin[bb->index], antloc[bb->index], |
4c26117a | 151 | transp[bb->index], antout[bb->index])) |
9ca8d59e | 152 | /* If the in state of this block changed, then we need |
153 | to add the predecessors of this block to the worklist | |
154 | if they are not already on the worklist. */ | |
cd665a06 | 155 | FOR_EACH_EDGE (e, ei, bb->preds) |
9ca8d59e | 156 | if (!e->src->aux && e->src != ENTRY_BLOCK_PTR) |
e48ba7af | 157 | { |
2c59145b | 158 | *qin++ = e->src; |
9ca8d59e | 159 | e->src->aux = e; |
2c59145b | 160 | qlen++; |
161 | if (qin >= qend) | |
8851e806 | 162 | qin = worklist; |
e48ba7af | 163 | } |
e48ba7af | 164 | } |
9ca8d59e | 165 | |
82f7392b | 166 | clear_aux_for_edges (); |
167 | clear_aux_for_blocks (); | |
2c59145b | 168 | free (worklist); |
e48ba7af | 169 | } |
170 | ||
7bcd381b | 171 | /* Compute the earliest vector for edge based lcm. */ |
9ca8d59e | 172 | |
e48ba7af | 173 | static void |
3ad4992f | 174 | compute_earliest (struct edge_list *edge_list, int n_exprs, sbitmap *antin, |
175 | sbitmap *antout, sbitmap *avout, sbitmap *kill, | |
176 | sbitmap *earliest) | |
e48ba7af | 177 | { |
7bcd381b | 178 | sbitmap difference, temp_bitmap; |
5ab08585 | 179 | int x, num_edges; |
7bcd381b | 180 | basic_block pred, succ; |
e48ba7af | 181 | |
7bcd381b | 182 | num_edges = NUM_EDGES (edge_list); |
e48ba7af | 183 | |
7bcd381b | 184 | difference = sbitmap_alloc (n_exprs); |
185 | temp_bitmap = sbitmap_alloc (n_exprs); | |
e48ba7af | 186 | |
7bcd381b | 187 | for (x = 0; x < num_edges; x++) |
e48ba7af | 188 | { |
7bcd381b | 189 | pred = INDEX_EDGE_PRED_BB (edge_list, x); |
190 | succ = INDEX_EDGE_SUCC_BB (edge_list, x); | |
191 | if (pred == ENTRY_BLOCK_PTR) | |
53c5d9d4 | 192 | bitmap_copy (earliest[x], antin[succ->index]); |
7bcd381b | 193 | else |
8851e806 | 194 | { |
742ee135 | 195 | if (succ == EXIT_BLOCK_PTR) |
53c5d9d4 | 196 | bitmap_clear (earliest[x]); |
7bcd381b | 197 | else |
e48ba7af | 198 | { |
53c5d9d4 | 199 | bitmap_and_compl (difference, antin[succ->index], |
b3d6de89 | 200 | avout[pred->index]); |
53c5d9d4 | 201 | bitmap_not (temp_bitmap, antout[pred->index]); |
202 | bitmap_and_or (earliest[x], difference, | |
b3d6de89 | 203 | kill[pred->index], temp_bitmap); |
e48ba7af | 204 | } |
205 | } | |
e48ba7af | 206 | } |
9ca8d59e | 207 | |
f5123ed5 | 208 | sbitmap_free (temp_bitmap); |
209 | sbitmap_free (difference); | |
e48ba7af | 210 | } |
211 | ||
2325f0e2 | 212 | /* later(p,s) is dependent on the calculation of laterin(p). |
213 | laterin(p) is dependent on the calculation of later(p2,p). | |
214 | ||
215 | laterin(ENTRY) is defined as all 0's | |
216 | later(ENTRY, succs(ENTRY)) are defined using laterin(ENTRY) | |
217 | laterin(succs(ENTRY)) is defined by later(ENTRY, succs(ENTRY)). | |
218 | ||
219 | If we progress in this manner, starting with all basic blocks | |
220 | in the work list, anytime we change later(bb), we need to add | |
221 | succs(bb) to the worklist if they are not already on the worklist. | |
222 | ||
223 | Boundary conditions: | |
224 | ||
225 | We prime the worklist all the normal basic blocks. The ENTRY block can | |
226 | never be added to the worklist since it is never the successor of any | |
227 | block. We explicitly prevent the EXIT block from being added to the | |
228 | worklist. | |
229 | ||
230 | We optimistically initialize LATER. That is the only time this routine | |
231 | will compute LATER for an edge out of the entry block since the entry | |
232 | block is never on the worklist. Thus, LATERIN is neither used nor | |
233 | computed for the ENTRY block. | |
234 | ||
235 | Since the EXIT block is never added to the worklist, we will neither | |
236 | use nor compute LATERIN for the exit block. Edges which reach the | |
237 | EXIT block are handled in the normal fashion inside the loop. However, | |
238 | the insertion/deletion computation needs LATERIN(EXIT), so we have | |
239 | to compute it. */ | |
5ab08585 | 240 | |
e48ba7af | 241 | static void |
3ad4992f | 242 | compute_laterin (struct edge_list *edge_list, sbitmap *earliest, |
243 | sbitmap *antloc, sbitmap *later, sbitmap *laterin) | |
e48ba7af | 244 | { |
4c26117a | 245 | int num_edges, i; |
2325f0e2 | 246 | edge e; |
4c26117a | 247 | basic_block *worklist, *qin, *qout, *qend, bb; |
2c59145b | 248 | unsigned int qlen; |
cd665a06 | 249 | edge_iterator ei; |
e48ba7af | 250 | |
7bcd381b | 251 | num_edges = NUM_EDGES (edge_list); |
e48ba7af | 252 | |
2325f0e2 | 253 | /* Allocate a worklist array/queue. Entries are only added to the |
254 | list if they were not already on the list. So the size is | |
255 | bounded by the number of basic blocks. */ | |
2c59145b | 256 | qin = qout = worklist |
a28770e1 | 257 | = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun)); |
2325f0e2 | 258 | |
259 | /* Initialize a mapping from each edge to its index. */ | |
260 | for (i = 0; i < num_edges; i++) | |
9ffd5d6d | 261 | INDEX_EDGE (edge_list, i)->aux = (void *) (size_t) i; |
2325f0e2 | 262 | |
263 | /* We want a maximal solution, so initially consider LATER true for | |
264 | all edges. This allows propagation through a loop since the incoming | |
265 | loop edge will have LATER set, so if all the other incoming edges | |
266 | to the loop are set, then LATERIN will be set for the head of the | |
267 | loop. | |
268 | ||
269 | If the optimistic setting of LATER on that edge was incorrect (for | |
270 | example the expression is ANTLOC in a block within the loop) then | |
271 | this algorithm will detect it when we process the block at the head | |
272 | of the optimistic edge. That will requeue the affected blocks. */ | |
53c5d9d4 | 273 | bitmap_vector_ones (later, num_edges); |
2325f0e2 | 274 | |
048599b9 | 275 | /* Note that even though we want an optimistic setting of LATER, we |
276 | do not want to be overly optimistic. Consider an outgoing edge from | |
277 | the entry block. That edge should always have a LATER value the | |
278 | same as EARLIEST for that edge. */ | |
cd665a06 | 279 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) |
53c5d9d4 | 280 | bitmap_copy (later[(size_t) e->aux], earliest[(size_t) e->aux]); |
048599b9 | 281 | |
2325f0e2 | 282 | /* Add all the blocks to the worklist. This prevents an early exit from |
283 | the loop given our optimistic initialization of LATER above. */ | |
4c26117a | 284 | FOR_EACH_BB (bb) |
e48ba7af | 285 | { |
4c26117a | 286 | *qin++ = bb; |
287 | bb->aux = bb; | |
7bcd381b | 288 | } |
d4d93ea0 | 289 | |
2c59145b | 290 | /* Note that we do not use the last allocated element for our queue, |
4d2e5d52 | 291 | as EXIT_BLOCK is never inserted into it. */ |
d4d93ea0 | 292 | qin = worklist; |
a28770e1 | 293 | qend = &worklist[n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS]; |
294 | qlen = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; | |
7bcd381b | 295 | |
2325f0e2 | 296 | /* Iterate until the worklist is empty. */ |
2c59145b | 297 | while (qlen) |
7bcd381b | 298 | { |
2325f0e2 | 299 | /* Take the first entry off the worklist. */ |
4c26117a | 300 | bb = *qout++; |
301 | bb->aux = NULL; | |
2c59145b | 302 | qlen--; |
303 | if (qout >= qend) | |
8851e806 | 304 | qout = worklist; |
2325f0e2 | 305 | |
306 | /* Compute the intersection of LATERIN for each incoming edge to B. */ | |
53c5d9d4 | 307 | bitmap_ones (laterin[bb->index]); |
cd665a06 | 308 | FOR_EACH_EDGE (e, ei, bb->preds) |
53c5d9d4 | 309 | bitmap_and (laterin[bb->index], laterin[bb->index], |
d4d93ea0 | 310 | later[(size_t)e->aux]); |
2325f0e2 | 311 | |
312 | /* Calculate LATER for all outgoing edges. */ | |
cd665a06 | 313 | FOR_EACH_EDGE (e, ei, bb->succs) |
53c5d9d4 | 314 | if (bitmap_ior_and_compl (later[(size_t) e->aux], |
b3d6de89 | 315 | earliest[(size_t) e->aux], |
316 | laterin[e->src->index], | |
317 | antloc[e->src->index]) | |
9ca8d59e | 318 | /* If LATER for an outgoing edge was changed, then we need |
319 | to add the target of the outgoing edge to the worklist. */ | |
320 | && e->dest != EXIT_BLOCK_PTR && e->dest->aux == 0) | |
321 | { | |
2c59145b | 322 | *qin++ = e->dest; |
9ca8d59e | 323 | e->dest->aux = e; |
2c59145b | 324 | qlen++; |
325 | if (qin >= qend) | |
326 | qin = worklist; | |
9ca8d59e | 327 | } |
e48ba7af | 328 | } |
329 | ||
2325f0e2 | 330 | /* Computation of insertion and deletion points requires computing LATERIN |
331 | for the EXIT block. We allocated an extra entry in the LATERIN array | |
332 | for just this purpose. */ | |
53c5d9d4 | 333 | bitmap_ones (laterin[last_basic_block]); |
cd665a06 | 334 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
53c5d9d4 | 335 | bitmap_and (laterin[last_basic_block], |
f20183e6 | 336 | laterin[last_basic_block], |
9ffd5d6d | 337 | later[(size_t) e->aux]); |
2325f0e2 | 338 | |
82f7392b | 339 | clear_aux_for_edges (); |
2c59145b | 340 | free (worklist); |
e48ba7af | 341 | } |
342 | ||
7bcd381b | 343 | /* Compute the insertion and deletion points for edge based LCM. */ |
9ca8d59e | 344 | |
7bcd381b | 345 | static void |
3ad4992f | 346 | compute_insert_delete (struct edge_list *edge_list, sbitmap *antloc, |
347 | sbitmap *later, sbitmap *laterin, sbitmap *insert, | |
9ce37fa7 | 348 | sbitmap *del) |
7bcd381b | 349 | { |
350 | int x; | |
4c26117a | 351 | basic_block bb; |
e48ba7af | 352 | |
4c26117a | 353 | FOR_EACH_BB (bb) |
53c5d9d4 | 354 | bitmap_and_compl (del[bb->index], antloc[bb->index], |
d4d93ea0 | 355 | laterin[bb->index]); |
5ab08585 | 356 | |
7bcd381b | 357 | for (x = 0; x < NUM_EDGES (edge_list); x++) |
358 | { | |
359 | basic_block b = INDEX_EDGE_SUCC_BB (edge_list, x); | |
9ca8d59e | 360 | |
7bcd381b | 361 | if (b == EXIT_BLOCK_PTR) |
53c5d9d4 | 362 | bitmap_and_compl (insert[x], later[x], laterin[last_basic_block]); |
7bcd381b | 363 | else |
53c5d9d4 | 364 | bitmap_and_compl (insert[x], later[x], laterin[b->index]); |
7bcd381b | 365 | } |
366 | } | |
e48ba7af | 367 | |
9ca8d59e | 368 | /* Given local properties TRANSP, ANTLOC, AVOUT, KILL return the insert and |
369 | delete vectors for edge based LCM. Returns an edgelist which is used to | |
370 | map the insert vector to what edge an expression should be inserted on. */ | |
e48ba7af | 371 | |
7bcd381b | 372 | struct edge_list * |
3f5be5f4 | 373 | pre_edge_lcm (int n_exprs, sbitmap *transp, |
3ad4992f | 374 | sbitmap *avloc, sbitmap *antloc, sbitmap *kill, |
9ce37fa7 | 375 | sbitmap **insert, sbitmap **del) |
e48ba7af | 376 | { |
7bcd381b | 377 | sbitmap *antin, *antout, *earliest; |
378 | sbitmap *avin, *avout; | |
379 | sbitmap *later, *laterin; | |
380 | struct edge_list *edge_list; | |
381 | int num_edges; | |
e48ba7af | 382 | |
7bcd381b | 383 | edge_list = create_edge_list (); |
384 | num_edges = NUM_EDGES (edge_list); | |
e48ba7af | 385 | |
7bcd381b | 386 | #ifdef LCM_DEBUG_INFO |
3f5be5f4 | 387 | if (dump_file) |
e48ba7af | 388 | { |
3f5be5f4 | 389 | fprintf (dump_file, "Edge List:\n"); |
390 | verify_edge_list (dump_file, edge_list); | |
391 | print_edge_list (dump_file, edge_list); | |
53c5d9d4 | 392 | dump_bitmap_vector (dump_file, "transp", "", transp, last_basic_block); |
393 | dump_bitmap_vector (dump_file, "antloc", "", antloc, last_basic_block); | |
394 | dump_bitmap_vector (dump_file, "avloc", "", avloc, last_basic_block); | |
395 | dump_bitmap_vector (dump_file, "kill", "", kill, last_basic_block); | |
e48ba7af | 396 | } |
7bcd381b | 397 | #endif |
e48ba7af | 398 | |
7bcd381b | 399 | /* Compute global availability. */ |
f20183e6 | 400 | avin = sbitmap_vector_alloc (last_basic_block, n_exprs); |
401 | avout = sbitmap_vector_alloc (last_basic_block, n_exprs); | |
7bcd381b | 402 | compute_available (avloc, kill, avout, avin); |
cca23eb2 | 403 | sbitmap_vector_free (avin); |
e48ba7af | 404 | |
7bcd381b | 405 | /* Compute global anticipatability. */ |
f20183e6 | 406 | antin = sbitmap_vector_alloc (last_basic_block, n_exprs); |
407 | antout = sbitmap_vector_alloc (last_basic_block, n_exprs); | |
7bcd381b | 408 | compute_antinout_edge (antloc, transp, antin, antout); |
e48ba7af | 409 | |
7bcd381b | 410 | #ifdef LCM_DEBUG_INFO |
3f5be5f4 | 411 | if (dump_file) |
e48ba7af | 412 | { |
53c5d9d4 | 413 | dump_bitmap_vector (dump_file, "antin", "", antin, last_basic_block); |
414 | dump_bitmap_vector (dump_file, "antout", "", antout, last_basic_block); | |
e48ba7af | 415 | } |
7bcd381b | 416 | #endif |
e48ba7af | 417 | |
7bcd381b | 418 | /* Compute earliestness. */ |
419 | earliest = sbitmap_vector_alloc (num_edges, n_exprs); | |
420 | compute_earliest (edge_list, n_exprs, antin, antout, avout, kill, earliest); | |
e48ba7af | 421 | |
7bcd381b | 422 | #ifdef LCM_DEBUG_INFO |
3f5be5f4 | 423 | if (dump_file) |
53c5d9d4 | 424 | dump_bitmap_vector (dump_file, "earliest", "", earliest, num_edges); |
7bcd381b | 425 | #endif |
e48ba7af | 426 | |
cca23eb2 | 427 | sbitmap_vector_free (antout); |
428 | sbitmap_vector_free (antin); | |
429 | sbitmap_vector_free (avout); | |
e48ba7af | 430 | |
7bcd381b | 431 | later = sbitmap_vector_alloc (num_edges, n_exprs); |
9ca8d59e | 432 | |
7bcd381b | 433 | /* Allocate an extra element for the exit block in the laterin vector. */ |
f20183e6 | 434 | laterin = sbitmap_vector_alloc (last_basic_block + 1, n_exprs); |
2325f0e2 | 435 | compute_laterin (edge_list, earliest, antloc, later, laterin); |
436 | ||
7bcd381b | 437 | #ifdef LCM_DEBUG_INFO |
3f5be5f4 | 438 | if (dump_file) |
7bcd381b | 439 | { |
53c5d9d4 | 440 | dump_bitmap_vector (dump_file, "laterin", "", laterin, last_basic_block + 1); |
441 | dump_bitmap_vector (dump_file, "later", "", later, num_edges); | |
7bcd381b | 442 | } |
443 | #endif | |
e48ba7af | 444 | |
cca23eb2 | 445 | sbitmap_vector_free (earliest); |
7bcd381b | 446 | |
447 | *insert = sbitmap_vector_alloc (num_edges, n_exprs); | |
9ce37fa7 | 448 | *del = sbitmap_vector_alloc (last_basic_block, n_exprs); |
53c5d9d4 | 449 | bitmap_vector_clear (*insert, num_edges); |
450 | bitmap_vector_clear (*del, last_basic_block); | |
9ce37fa7 | 451 | compute_insert_delete (edge_list, antloc, later, laterin, *insert, *del); |
e48ba7af | 452 | |
cca23eb2 | 453 | sbitmap_vector_free (laterin); |
454 | sbitmap_vector_free (later); | |
7bcd381b | 455 | |
456 | #ifdef LCM_DEBUG_INFO | |
3f5be5f4 | 457 | if (dump_file) |
e48ba7af | 458 | { |
53c5d9d4 | 459 | dump_bitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges); |
460 | dump_bitmap_vector (dump_file, "pre_delete_map", "", *del, | |
f20183e6 | 461 | last_basic_block); |
e48ba7af | 462 | } |
7bcd381b | 463 | #endif |
e48ba7af | 464 | |
7bcd381b | 465 | return edge_list; |
466 | } | |
3b7e1f27 | 467 | |
468 | /* Compute the AVIN and AVOUT vectors from the AVLOC and KILL vectors. | |
469 | Return the number of passes we performed to iterate to a solution. */ | |
470 | ||
2325f0e2 | 471 | void |
3ad4992f | 472 | compute_available (sbitmap *avloc, sbitmap *kill, sbitmap *avout, |
473 | sbitmap *avin) | |
e48ba7af | 474 | { |
3b7e1f27 | 475 | edge e; |
4c26117a | 476 | basic_block *worklist, *qin, *qout, *qend, bb; |
3b7e1f27 | 477 | unsigned int qlen; |
cd665a06 | 478 | edge_iterator ei; |
3b7e1f27 | 479 | |
480 | /* Allocate a worklist array/queue. Entries are only added to the | |
481 | list if they were not already on the list. So the size is | |
482 | bounded by the number of basic blocks. */ | |
48e1416a | 483 | qin = qout = worklist = |
a28770e1 | 484 | XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
3b7e1f27 | 485 | |
486 | /* We want a maximal solution. */ | |
53c5d9d4 | 487 | bitmap_vector_ones (avout, last_basic_block); |
3b7e1f27 | 488 | |
489 | /* Put every block on the worklist; this is necessary because of the | |
490 | optimistic initialization of AVOUT above. */ | |
4c26117a | 491 | FOR_EACH_BB (bb) |
3b7e1f27 | 492 | { |
4c26117a | 493 | *qin++ = bb; |
494 | bb->aux = bb; | |
3b7e1f27 | 495 | } |
496 | ||
497 | qin = worklist; | |
a28770e1 | 498 | qend = &worklist[n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS]; |
499 | qlen = n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; | |
3b7e1f27 | 500 | |
501 | /* Mark blocks which are successors of the entry block so that we | |
502 | can easily identify them below. */ | |
cd665a06 | 503 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) |
3b7e1f27 | 504 | e->dest->aux = ENTRY_BLOCK_PTR; |
505 | ||
506 | /* Iterate until the worklist is empty. */ | |
507 | while (qlen) | |
508 | { | |
509 | /* Take the first entry off the worklist. */ | |
4c26117a | 510 | bb = *qout++; |
3b7e1f27 | 511 | qlen--; |
512 | ||
513 | if (qout >= qend) | |
8851e806 | 514 | qout = worklist; |
3b7e1f27 | 515 | |
516 | /* If one of the predecessor blocks is the ENTRY block, then the | |
517 | intersection of avouts is the null set. We can identify such blocks | |
518 | by the special value in the AUX field in the block structure. */ | |
4c26117a | 519 | if (bb->aux == ENTRY_BLOCK_PTR) |
3b7e1f27 | 520 | /* Do not clear the aux field for blocks which are successors of the |
521 | ENTRY block. That way we never add then to the worklist again. */ | |
53c5d9d4 | 522 | bitmap_clear (avin[bb->index]); |
3b7e1f27 | 523 | else |
524 | { | |
525 | /* Clear the aux field of this block so that it can be added to | |
526 | the worklist again if necessary. */ | |
4c26117a | 527 | bb->aux = NULL; |
08b7917c | 528 | bitmap_intersection_of_preds (avin[bb->index], avout, bb); |
3b7e1f27 | 529 | } |
530 | ||
53c5d9d4 | 531 | if (bitmap_ior_and_compl (avout[bb->index], avloc[bb->index], |
d4d93ea0 | 532 | avin[bb->index], kill[bb->index])) |
3b7e1f27 | 533 | /* If the out state of this block changed, then we need |
534 | to add the successors of this block to the worklist | |
535 | if they are not already on the worklist. */ | |
cd665a06 | 536 | FOR_EACH_EDGE (e, ei, bb->succs) |
3b7e1f27 | 537 | if (!e->dest->aux && e->dest != EXIT_BLOCK_PTR) |
538 | { | |
539 | *qin++ = e->dest; | |
540 | e->dest->aux = e; | |
541 | qlen++; | |
542 | ||
543 | if (qin >= qend) | |
8851e806 | 544 | qin = worklist; |
3b7e1f27 | 545 | } |
546 | } | |
547 | ||
548 | clear_aux_for_edges (); | |
549 | clear_aux_for_blocks (); | |
550 | free (worklist); | |
e48ba7af | 551 | } |
552 | ||
7bcd381b | 553 | /* Compute the farthest vector for edge based lcm. */ |
9ca8d59e | 554 | |
e48ba7af | 555 | static void |
3ad4992f | 556 | compute_farthest (struct edge_list *edge_list, int n_exprs, |
557 | sbitmap *st_avout, sbitmap *st_avin, sbitmap *st_antin, | |
558 | sbitmap *kill, sbitmap *farthest) | |
e48ba7af | 559 | { |
7bcd381b | 560 | sbitmap difference, temp_bitmap; |
5ab08585 | 561 | int x, num_edges; |
7bcd381b | 562 | basic_block pred, succ; |
e48ba7af | 563 | |
7bcd381b | 564 | num_edges = NUM_EDGES (edge_list); |
e48ba7af | 565 | |
7bcd381b | 566 | difference = sbitmap_alloc (n_exprs); |
567 | temp_bitmap = sbitmap_alloc (n_exprs); | |
e48ba7af | 568 | |
7bcd381b | 569 | for (x = 0; x < num_edges; x++) |
e48ba7af | 570 | { |
7bcd381b | 571 | pred = INDEX_EDGE_PRED_BB (edge_list, x); |
572 | succ = INDEX_EDGE_SUCC_BB (edge_list, x); | |
573 | if (succ == EXIT_BLOCK_PTR) | |
53c5d9d4 | 574 | bitmap_copy (farthest[x], st_avout[pred->index]); |
7bcd381b | 575 | else |
e48ba7af | 576 | { |
7bcd381b | 577 | if (pred == ENTRY_BLOCK_PTR) |
53c5d9d4 | 578 | bitmap_clear (farthest[x]); |
7bcd381b | 579 | else |
580 | { | |
53c5d9d4 | 581 | bitmap_and_compl (difference, st_avout[pred->index], |
b3d6de89 | 582 | st_antin[succ->index]); |
53c5d9d4 | 583 | bitmap_not (temp_bitmap, st_avin[succ->index]); |
584 | bitmap_and_or (farthest[x], difference, | |
b3d6de89 | 585 | kill[succ->index], temp_bitmap); |
7bcd381b | 586 | } |
e48ba7af | 587 | } |
e48ba7af | 588 | } |
9ca8d59e | 589 | |
f5123ed5 | 590 | sbitmap_free (temp_bitmap); |
591 | sbitmap_free (difference); | |
e48ba7af | 592 | } |
593 | ||
2325f0e2 | 594 | /* Compute nearer and nearerout vectors for edge based lcm. |
595 | ||
596 | This is the mirror of compute_laterin, additional comments on the | |
597 | implementation can be found before compute_laterin. */ | |
598 | ||
e48ba7af | 599 | static void |
3ad4992f | 600 | compute_nearerout (struct edge_list *edge_list, sbitmap *farthest, |
601 | sbitmap *st_avloc, sbitmap *nearer, sbitmap *nearerout) | |
e48ba7af | 602 | { |
4c26117a | 603 | int num_edges, i; |
2325f0e2 | 604 | edge e; |
4c26117a | 605 | basic_block *worklist, *tos, bb; |
cd665a06 | 606 | edge_iterator ei; |
e48ba7af | 607 | |
7bcd381b | 608 | num_edges = NUM_EDGES (edge_list); |
e48ba7af | 609 | |
2325f0e2 | 610 | /* Allocate a worklist array/queue. Entries are only added to the |
611 | list if they were not already on the list. So the size is | |
612 | bounded by the number of basic blocks. */ | |
a28770e1 | 613 | tos = worklist = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) + 1); |
e48ba7af | 614 | |
2325f0e2 | 615 | /* Initialize NEARER for each edge and build a mapping from an edge to |
616 | its index. */ | |
617 | for (i = 0; i < num_edges; i++) | |
9ffd5d6d | 618 | INDEX_EDGE (edge_list, i)->aux = (void *) (size_t) i; |
7bcd381b | 619 | |
2325f0e2 | 620 | /* We want a maximal solution. */ |
53c5d9d4 | 621 | bitmap_vector_ones (nearer, num_edges); |
2325f0e2 | 622 | |
048599b9 | 623 | /* Note that even though we want an optimistic setting of NEARER, we |
624 | do not want to be overly optimistic. Consider an incoming edge to | |
625 | the exit block. That edge should always have a NEARER value the | |
626 | same as FARTHEST for that edge. */ | |
cd665a06 | 627 | FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds) |
53c5d9d4 | 628 | bitmap_copy (nearer[(size_t)e->aux], farthest[(size_t)e->aux]); |
048599b9 | 629 | |
2325f0e2 | 630 | /* Add all the blocks to the worklist. This prevents an early exit |
631 | from the loop given our optimistic initialization of NEARER. */ | |
4c26117a | 632 | FOR_EACH_BB (bb) |
e48ba7af | 633 | { |
4c26117a | 634 | *tos++ = bb; |
635 | bb->aux = bb; | |
7bcd381b | 636 | } |
5ab08585 | 637 | |
2325f0e2 | 638 | /* Iterate until the worklist is empty. */ |
639 | while (tos != worklist) | |
7bcd381b | 640 | { |
2325f0e2 | 641 | /* Take the first entry off the worklist. */ |
4c26117a | 642 | bb = *--tos; |
643 | bb->aux = NULL; | |
2325f0e2 | 644 | |
645 | /* Compute the intersection of NEARER for each outgoing edge from B. */ | |
53c5d9d4 | 646 | bitmap_ones (nearerout[bb->index]); |
cd665a06 | 647 | FOR_EACH_EDGE (e, ei, bb->succs) |
53c5d9d4 | 648 | bitmap_and (nearerout[bb->index], nearerout[bb->index], |
9ffd5d6d | 649 | nearer[(size_t) e->aux]); |
2325f0e2 | 650 | |
651 | /* Calculate NEARER for all incoming edges. */ | |
cd665a06 | 652 | FOR_EACH_EDGE (e, ei, bb->preds) |
53c5d9d4 | 653 | if (bitmap_ior_and_compl (nearer[(size_t) e->aux], |
b3d6de89 | 654 | farthest[(size_t) e->aux], |
655 | nearerout[e->dest->index], | |
656 | st_avloc[e->dest->index]) | |
9ca8d59e | 657 | /* If NEARER for an incoming edge was changed, then we need |
658 | to add the source of the incoming edge to the worklist. */ | |
659 | && e->src != ENTRY_BLOCK_PTR && e->src->aux == 0) | |
660 | { | |
661 | *tos++ = e->src; | |
662 | e->src->aux = e; | |
663 | } | |
7bcd381b | 664 | } |
e48ba7af | 665 | |
2325f0e2 | 666 | /* Computation of insertion and deletion points requires computing NEAREROUT |
667 | for the ENTRY block. We allocated an extra entry in the NEAREROUT array | |
668 | for just this purpose. */ | |
53c5d9d4 | 669 | bitmap_ones (nearerout[last_basic_block]); |
cd665a06 | 670 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) |
53c5d9d4 | 671 | bitmap_and (nearerout[last_basic_block], |
f20183e6 | 672 | nearerout[last_basic_block], |
9ffd5d6d | 673 | nearer[(size_t) e->aux]); |
2325f0e2 | 674 | |
82f7392b | 675 | clear_aux_for_edges (); |
2325f0e2 | 676 | free (tos); |
7bcd381b | 677 | } |
e48ba7af | 678 | |
7bcd381b | 679 | /* Compute the insertion and deletion points for edge based LCM. */ |
9ca8d59e | 680 | |
e48ba7af | 681 | static void |
3ad4992f | 682 | compute_rev_insert_delete (struct edge_list *edge_list, sbitmap *st_avloc, |
683 | sbitmap *nearer, sbitmap *nearerout, | |
9ce37fa7 | 684 | sbitmap *insert, sbitmap *del) |
e48ba7af | 685 | { |
7bcd381b | 686 | int x; |
4c26117a | 687 | basic_block bb; |
e48ba7af | 688 | |
4c26117a | 689 | FOR_EACH_BB (bb) |
53c5d9d4 | 690 | bitmap_and_compl (del[bb->index], st_avloc[bb->index], |
d4d93ea0 | 691 | nearerout[bb->index]); |
5ab08585 | 692 | |
7bcd381b | 693 | for (x = 0; x < NUM_EDGES (edge_list); x++) |
e48ba7af | 694 | { |
7bcd381b | 695 | basic_block b = INDEX_EDGE_PRED_BB (edge_list, x); |
696 | if (b == ENTRY_BLOCK_PTR) | |
53c5d9d4 | 697 | bitmap_and_compl (insert[x], nearer[x], nearerout[last_basic_block]); |
e48ba7af | 698 | else |
53c5d9d4 | 699 | bitmap_and_compl (insert[x], nearer[x], nearerout[b->index]); |
e48ba7af | 700 | } |
e48ba7af | 701 | } |
702 | ||
5ab08585 | 703 | /* Given local properties TRANSP, ST_AVLOC, ST_ANTLOC, KILL return the |
7bcd381b | 704 | insert and delete vectors for edge based reverse LCM. Returns an |
705 | edgelist which is used to map the insert vector to what edge | |
706 | an expression should be inserted on. */ | |
e48ba7af | 707 | |
7bcd381b | 708 | struct edge_list * |
3f5be5f4 | 709 | pre_edge_rev_lcm (int n_exprs, sbitmap *transp, |
3ad4992f | 710 | sbitmap *st_avloc, sbitmap *st_antloc, sbitmap *kill, |
9ce37fa7 | 711 | sbitmap **insert, sbitmap **del) |
e48ba7af | 712 | { |
7bcd381b | 713 | sbitmap *st_antin, *st_antout; |
714 | sbitmap *st_avout, *st_avin, *farthest; | |
715 | sbitmap *nearer, *nearerout; | |
716 | struct edge_list *edge_list; | |
27548a74 | 717 | int num_edges; |
7bcd381b | 718 | |
719 | edge_list = create_edge_list (); | |
720 | num_edges = NUM_EDGES (edge_list); | |
721 | ||
f0af5a88 | 722 | st_antin = sbitmap_vector_alloc (last_basic_block, n_exprs); |
723 | st_antout = sbitmap_vector_alloc (last_basic_block, n_exprs); | |
53c5d9d4 | 724 | bitmap_vector_clear (st_antin, last_basic_block); |
725 | bitmap_vector_clear (st_antout, last_basic_block); | |
7bcd381b | 726 | compute_antinout_edge (st_antloc, transp, st_antin, st_antout); |
727 | ||
728 | /* Compute global anticipatability. */ | |
f20183e6 | 729 | st_avout = sbitmap_vector_alloc (last_basic_block, n_exprs); |
730 | st_avin = sbitmap_vector_alloc (last_basic_block, n_exprs); | |
7bcd381b | 731 | compute_available (st_avloc, kill, st_avout, st_avin); |
732 | ||
733 | #ifdef LCM_DEBUG_INFO | |
3f5be5f4 | 734 | if (dump_file) |
7bcd381b | 735 | { |
3f5be5f4 | 736 | fprintf (dump_file, "Edge List:\n"); |
737 | verify_edge_list (dump_file, edge_list); | |
738 | print_edge_list (dump_file, edge_list); | |
53c5d9d4 | 739 | dump_bitmap_vector (dump_file, "transp", "", transp, last_basic_block); |
740 | dump_bitmap_vector (dump_file, "st_avloc", "", st_avloc, last_basic_block); | |
741 | dump_bitmap_vector (dump_file, "st_antloc", "", st_antloc, last_basic_block); | |
742 | dump_bitmap_vector (dump_file, "st_antin", "", st_antin, last_basic_block); | |
743 | dump_bitmap_vector (dump_file, "st_antout", "", st_antout, last_basic_block); | |
744 | dump_bitmap_vector (dump_file, "st_kill", "", kill, last_basic_block); | |
7bcd381b | 745 | } |
746 | #endif | |
e48ba7af | 747 | |
7bcd381b | 748 | #ifdef LCM_DEBUG_INFO |
3f5be5f4 | 749 | if (dump_file) |
7bcd381b | 750 | { |
53c5d9d4 | 751 | dump_bitmap_vector (dump_file, "st_avout", "", st_avout, last_basic_block); |
752 | dump_bitmap_vector (dump_file, "st_avin", "", st_avin, last_basic_block); | |
7bcd381b | 753 | } |
754 | #endif | |
e48ba7af | 755 | |
7bcd381b | 756 | /* Compute farthestness. */ |
757 | farthest = sbitmap_vector_alloc (num_edges, n_exprs); | |
5ab08585 | 758 | compute_farthest (edge_list, n_exprs, st_avout, st_avin, st_antin, |
7bcd381b | 759 | kill, farthest); |
760 | ||
761 | #ifdef LCM_DEBUG_INFO | |
3f5be5f4 | 762 | if (dump_file) |
53c5d9d4 | 763 | dump_bitmap_vector (dump_file, "farthest", "", farthest, num_edges); |
7bcd381b | 764 | #endif |
765 | ||
cca23eb2 | 766 | sbitmap_vector_free (st_antin); |
767 | sbitmap_vector_free (st_antout); | |
768 | ||
769 | sbitmap_vector_free (st_avin); | |
770 | sbitmap_vector_free (st_avout); | |
7bcd381b | 771 | |
772 | nearer = sbitmap_vector_alloc (num_edges, n_exprs); | |
9ca8d59e | 773 | |
7bcd381b | 774 | /* Allocate an extra element for the entry block. */ |
f20183e6 | 775 | nearerout = sbitmap_vector_alloc (last_basic_block + 1, n_exprs); |
2325f0e2 | 776 | compute_nearerout (edge_list, farthest, st_avloc, nearer, nearerout); |
7bcd381b | 777 | |
778 | #ifdef LCM_DEBUG_INFO | |
3f5be5f4 | 779 | if (dump_file) |
e48ba7af | 780 | { |
53c5d9d4 | 781 | dump_bitmap_vector (dump_file, "nearerout", "", nearerout, |
f20183e6 | 782 | last_basic_block + 1); |
53c5d9d4 | 783 | dump_bitmap_vector (dump_file, "nearer", "", nearer, num_edges); |
e48ba7af | 784 | } |
7bcd381b | 785 | #endif |
786 | ||
cca23eb2 | 787 | sbitmap_vector_free (farthest); |
7bcd381b | 788 | |
789 | *insert = sbitmap_vector_alloc (num_edges, n_exprs); | |
9ce37fa7 | 790 | *del = sbitmap_vector_alloc (last_basic_block, n_exprs); |
9ca8d59e | 791 | compute_rev_insert_delete (edge_list, st_avloc, nearer, nearerout, |
9ce37fa7 | 792 | *insert, *del); |
7bcd381b | 793 | |
cca23eb2 | 794 | sbitmap_vector_free (nearerout); |
795 | sbitmap_vector_free (nearer); | |
7bcd381b | 796 | |
797 | #ifdef LCM_DEBUG_INFO | |
3f5be5f4 | 798 | if (dump_file) |
7bcd381b | 799 | { |
53c5d9d4 | 800 | dump_bitmap_vector (dump_file, "pre_insert_map", "", *insert, num_edges); |
801 | dump_bitmap_vector (dump_file, "pre_delete_map", "", *del, | |
f20183e6 | 802 | last_basic_block); |
7bcd381b | 803 | } |
804 | #endif | |
7bcd381b | 805 | return edge_list; |
e48ba7af | 806 | } |
18862b5a | 807 |