2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief parallelizing Load/Store optimisation
23 * @author Christoph Mallon
39 #include "irnodeset.h"
46 #define OPTIMISE_LOAD_AFTER_LOAD
49 #define UNIMPLEMENTED abort();
52 DEBUG_ONLY(static firm_dbg_module_t *dbg);
55 static struct obstack obst;
56 static size_t count_addrs;
57 static ir_node** addrs;
60 static void AddressCollector(ir_node* node, void* env)
62 ir_nodeset_t* addrs_set = env;
65 addr = get_Load_ptr(node);
66 } else if (is_Store(node)) {
67 addr = get_Store_ptr(node);
71 ir_nodeset_insert(addrs_set, addr);
75 /* Collects all unique addresses used by load and store nodes of a graph and
76 * puts them into an array for later use */
77 static void CollectAddresses(ir_graph* irg)
79 ir_nodeset_t addrs_set;
81 ir_nodeset_init(&addrs_set);
82 irg_walk_graph(irg, AddressCollector, NULL, &addrs_set);
84 count_addrs = ir_nodeset_size(&addrs_set);
85 DB((dbg, LEVEL_1, "===> %+F uses %u unique addresses\n", irg, (unsigned int)count_addrs));
86 if (count_addrs != 0) {
87 ir_nodeset_iterator_t addr_iter;
90 addrs = NEW_ARR_D(ir_node*, &obst, count_addrs);
91 ir_nodeset_iterator_init(&addr_iter, &addrs_set);
92 for (i = 0; i < count_addrs; i++) {
93 ir_node* addr = ir_nodeset_iterator_next(&addr_iter);
95 set_irn_link(addr, (void *)i);
97 DB((dbg, LEVEL_2, "===> Collected unique symbolic address %+F\n", addr));
103 static void AliasSetAdder(ir_node* block, void* env)
105 ir_nodeset_t* alias_set;
108 alias_set = NEW_ARR_D(ir_nodeset_t, &obst, count_addrs);
109 for (i = 0; i < count_addrs; i++) {
110 ir_nodeset_init(&alias_set[i]);
112 set_irn_link(block, alias_set);
116 static void SetStartAddressesTop(ir_graph* irg)
118 ir_node* initial_mem;
119 ir_node* start_block;
120 ir_nodeset_t* start_addrs;
123 initial_mem = get_irg_initial_mem(irg);
124 start_block = get_irg_start_block(irg);
125 start_addrs = get_irn_link(start_block);
126 for (i = 0; i < count_addrs; i++) {
127 ir_nodeset_insert(&start_addrs[i], initial_mem);
129 mark_Block_block_visited(start_block);
133 static void AliasSetDestroyer(ir_node* block, void* env)
135 ir_nodeset_t* alias_set = get_irn_link(block);
138 for (i = 0; i < count_addrs; i++) {
139 ir_nodeset_destroy(&alias_set[i]);
144 static ir_alias_relation AliasTest(ir_graph* irg, ir_node* addr, ir_mode* mode, ir_node* other)
149 if (is_Proj(other)) other = get_Proj_pred(other);
151 if (is_Load(other)) {
152 other_addr = get_Load_ptr(other);
153 } else if (is_Store(other)) {
154 other_addr = get_Store_ptr(other);
159 other_mode = get_irn_mode(other);
160 return get_alias_relation(irg, addr, mode, other_addr, other_mode);
164 static ir_node* GenerateSync(ir_graph* irg, ir_node* block, ir_nodeset_t* after_set)
166 size_t set_size = ir_nodeset_size(after_set);
167 ir_nodeset_iterator_t iter;
169 assert(set_size != 0);
171 ir_nodeset_iterator_init(&iter, after_set);
173 return ir_nodeset_iterator_next(&iter);
178 NEW_ARR_A(ir_node*, in, set_size);
179 for (i = 0; i < set_size; i++) {
180 in[i] = ir_nodeset_iterator_next(&iter);
182 return new_r_Sync(irg, block, set_size, in);
187 static ir_node** unfinished_phis;
190 static void PlaceMemPhis(ir_graph* irg, ir_node* block, ir_node* phi)
193 size_t block_n_preds = get_Block_n_cfgpreds(block);
194 ir_nodeset_t* thissets;
199 thissets = get_irn_link(block);
200 NEW_ARR_A(ir_node*, in, block_n_preds);
201 for (j = 0; j < count_addrs; j++) {
204 for (i = 0; i < block_n_preds; i++) {
205 ir_node* pred_block = get_nodes_block(get_Phi_pred(phi, i)); // TODO get_Block_cfgpred_block(block, i);
206 ir_nodeset_t* predsets = get_irn_link(pred_block);
207 size_t predset_size = ir_nodeset_size(&predsets[j]);
209 if (predset_size == 0) {
210 in[i] = new_r_Unknown(irg, mode_M);
213 in[i] = GenerateSync(irg, pred_block, &predsets[j]);
216 new_phi = new_r_Phi(irg, block, block_n_preds, in, mode_M);
218 set_irn_link(new_phi, unfinished_phis[j]);
219 unfinished_phis[j] = new_phi;
221 ir_nodeset_insert(&thissets[j], new_phi);
226 static int WalkMem(ir_graph* irg, ir_node* node, ir_node* last_block);
229 static void WalkMemPhi(ir_graph* irg, ir_node* block, ir_node* phi)
231 size_t n = get_Phi_n_preds(phi);
234 for (i = 0; i < n; i++) {
235 WalkMem(irg, get_Phi_pred(phi, i), block);
238 PlaceMemPhis(irg, block, phi);
239 exchange(phi, new_Bad());
243 static void PlaceLoad(ir_graph* irg, ir_node* block, ir_node* load, ir_node* memory)
245 ir_node* addr = get_Load_ptr(load);
246 size_t addr_idx = (size_t)get_irn_link(addr);
247 ir_nodeset_t* interfere_sets = get_irn_link(block);
248 ir_nodeset_t* interfere_set = &interfere_sets[addr_idx];
249 size_t size = ir_nodeset_size(interfere_set);
250 ir_nodeset_iterator_t interfere_iter;
254 ir_nodeset_iterator_init(&interfere_iter, interfere_set);
256 ir_node* after = ir_nodeset_iterator_next(&interfere_iter);
257 if (is_Proj(after)) {
258 ir_node* pred = get_Proj_pred(after);
260 #ifdef OPTIMISE_LOAD_AFTER_LOAD
261 if (get_Load_ptr(pred) == addr && get_Load_mode(pred) == get_Load_mode(load)) {
262 exchange(load, pred);
266 after = get_Load_mem(pred);
269 DB((dbg, LEVEL_3, "===> %+F must be executed after %+F\n", load, after));
270 set_Load_mem(load, after);
275 NEW_ARR_A(ir_node*, after_set, size);
276 for (i = 0; i < size; i++) {
277 ir_node* mem = ir_nodeset_iterator_next(&interfere_iter);
279 ir_node* pred = get_Proj_pred(mem);
281 #ifdef OPTIMISE_LOAD_AFTER_LOAD
282 if (get_Load_ptr(pred) == addr && get_Load_mode(pred) == get_Load_mode(load)) {
283 exchange(load, pred);
287 mem = get_Load_mem(pred);
290 DB((dbg, LEVEL_3, "===> %+F must be executed after %+F\n", load, mem));
292 sync = new_r_Sync(irg, block, size, after_set);
294 set_Load_mem(load, sync);
297 for (i = 0; i < count_addrs; i++) {
298 ir_mode* mode = get_Load_mode(load);
299 ir_node* other_addr = addrs[i];
300 ir_mode* other_mode = mode; // XXX second mode is nonsense
301 ir_alias_relation rel = get_alias_relation(irg, addr, mode, other_addr, other_mode);
304 DB((dbg, LEVEL_3, "===> Testing for alias between %+F and %+F. Relation is %d\n", addr, other_addr, rel));
305 if (rel == no_alias) {
308 DB((dbg, LEVEL_3, "===> %+F potentially aliases address %+F\n", load, other_addr));
310 ir_nodeset_iterator_init(&interfere_iter, &interfere_sets[i]);
311 while ((other_node = ir_nodeset_iterator_next(&interfere_iter)) != NULL) {
312 if (!is_Proj(other_node) || !is_Store(get_Proj_pred(other_node))) continue;
313 if (AliasTest(irg, addr, mode, other_node) != no_alias) {
314 DB((dbg, LEVEL_3, "===> Removing %+F from execute-after set of %+F due to %+F\n", other_node, addrs[i], load));
315 ir_nodeset_remove_iterator(&interfere_sets[i], &interfere_iter);
319 ir_nodeset_insert(&interfere_sets[i], memory);
324 static void PlaceStore(ir_graph* irg, ir_node* block, ir_node* store, ir_node* memory)
326 ir_node* addr = get_Store_ptr(store);
327 size_t addr_idx = (size_t)get_irn_link(addr);
328 ir_nodeset_t* interfere_sets = get_irn_link(block);
329 ir_nodeset_t* interfere_set = &interfere_sets[addr_idx];
333 after = GenerateSync(irg, block, interfere_set);
334 set_Store_mem(store, after);
336 for (i = 0; i < count_addrs; i++) {
337 ir_nodeset_iterator_t interfere_iter;
338 ir_mode* mode = get_irn_mode(get_Store_value(store));
339 ir_node* other_addr = addrs[i];
340 ir_mode* other_mode = mode; // XXX second mode is nonsense
341 ir_alias_relation rel = get_alias_relation(irg, addr, mode, other_addr, other_mode);
344 DB((dbg, LEVEL_3, "===> Testing for alias between %+F and %+F. Relation is %d\n", addr, other_addr, rel));
345 if (rel == no_alias) {
348 DB((dbg, LEVEL_3, "===> %+F potentially aliases address %+F\n", store, other_addr));
350 ir_nodeset_iterator_init(&interfere_iter, &interfere_sets[i]);
351 while ((other_node = ir_nodeset_iterator_next(&interfere_iter)) != NULL) {
352 if (AliasTest(irg, addr, mode, other_node) != no_alias) {
353 DB((dbg, LEVEL_3, "===> Removing %+F from execute-after set of %+F due to %+F\n", other_node, addrs[i], store));
354 ir_nodeset_remove_iterator(&interfere_sets[i], &interfere_iter);
358 ir_nodeset_insert(&interfere_sets[i], memory);
363 static int WalkMem(ir_graph* irg, ir_node* node, ir_node* last_block)
365 int block_change = 0;
366 ir_node* block = get_nodes_block(node);
368 ir_node* memory = node;
369 ir_nodeset_t* addr_sets;
371 if (block != last_block) {
372 DB((dbg, LEVEL_3, "===> Changing block from %+F to %+F\n", last_block, block));
374 if (Block_not_block_visited(block)) {
375 mark_Block_block_visited(block);
377 DB((dbg, LEVEL_2, "===> Hit already visited block at %+F\n", node));
383 if (is_Proj(node)) node = get_Proj_pred(node);
386 WalkMemPhi(irg, block, node);
388 } else if (is_Sync(node)) {
390 } else if (is_Return(node)) {
391 pred = get_Return_mem(node);
393 pred = get_fragile_op_mem(node);
396 if (WalkMem(irg, pred, block)) {
397 // There was a block change
398 size_t block_arity = get_Block_n_cfgpreds(block);
400 DB((dbg, LEVEL_3, "===> There is a block change before %+F\n", node));
401 if (block_arity == 1) {
402 // Just one predecessor, inherit its alias sets
403 ir_node* pred_block = get_nodes_block(pred);
404 ir_nodeset_t* predsets = get_irn_link(pred_block);
405 ir_nodeset_t* thissets = get_irn_link(block);
408 DB((dbg, LEVEL_3, "===> Copying the only predecessor's address sets\n"));
410 if (ir_nodeset_size(&predsets[0]) == 0) {
413 DB((dbg, LEVEL_3, "===> The predecessor was not finished yet\n"));
414 assert(!Block_not_block_visited(pred_block));
416 unknown = new_r_Unknown(irg, mode_M);
417 for (i = 0; i < count_addrs; i++) {
418 ir_node* phi_unk = new_r_Phi(irg, block, 1, &unknown, mode_M);
419 DB((dbg, LEVEL_3, "===> Placing unfinished %+F for %+F in %+F\n", phi_unk, addrs[i], block));
420 set_irn_link(phi_unk, unfinished_phis[i]);
421 unfinished_phis[i] = phi_unk;
422 ir_nodeset_insert(&thissets[i], phi_unk);
425 for (i = 0; i < count_addrs; i++) {
426 ir_nodeset_iterator_t prediter;
429 ir_nodeset_iterator_init(&prediter, &predsets[i]);
430 while ((addr = ir_nodeset_iterator_next(&prediter)) != NULL) {
431 ir_nodeset_insert(&thissets[i], addr);
438 DB((dbg, LEVEL_3, "===> Detotalising %+F\n", node));
440 addr_sets = get_irn_link(block);
443 PlaceLoad(irg, block, node, memory);
444 } else if (is_Store(node)) {
445 PlaceStore(irg, block, node, memory);
447 ir_nodeset_t sync_set;
451 DB((dbg, LEVEL_3, "===> Fallback: %+F aliases everything\n", node));
453 ir_nodeset_init(&sync_set);
454 for (i = 0; i < count_addrs; i++) {
455 ir_nodeset_iterator_t iter;
458 ir_nodeset_iterator_init(&iter, &addr_sets[i]);
459 while ((mem = ir_nodeset_iterator_next(&iter)) != NULL) {
460 ir_nodeset_insert(&sync_set, mem);
464 after = GenerateSync(irg, block, &sync_set);
465 set_irn_n(node, 0, after); // XXX unnice way to set the memory input
467 for (i = 0; i < count_addrs; i++) {
468 ir_nodeset_iterator_t iter;
469 ir_nodeset_iterator_init(&iter, &addr_sets[i]);
470 while (ir_nodeset_iterator_next(&iter) != NULL) {
471 ir_nodeset_remove_iterator(&addr_sets[i], &iter);
473 ir_nodeset_insert(&addr_sets[i], memory);
481 static void FinalisePhis(ir_graph* irg)
485 for (i = 0; i < count_addrs; i++) {
489 for (phi = unfinished_phis[i]; phi != NULL; phi = next_phi) {
490 ir_node* block = get_nodes_block(phi);
491 size_t block_n_preds = get_Block_n_cfgpreds(block);
493 next_phi = get_irn_link(phi);
495 DB((dbg, LEVEL_4, "===> Finialising phi %+F in %+F\n", phi, block));
497 if (block_n_preds == 1) {
498 ir_node* pred_block = get_Block_cfgpred_block(block, 0);
499 ir_nodeset_t* pred_sets = get_irn_link(pred_block);
500 ir_node* after = GenerateSync(irg, pred_block, &pred_sets[i]);
502 assert(is_Unknown(get_Phi_pred(phi, 0)));
503 exchange(phi, after);
508 NEW_ARR_A(ir_node*, in, block_n_preds);
509 for (j = 0; j < block_n_preds; j++) {
510 ir_node* pred_block = get_Block_cfgpred_block(block, j);
511 ir_nodeset_t* pred_sets = get_irn_link(pred_block);
513 if (is_Unknown(get_Phi_pred(phi, j))) {
514 set_Phi_pred(phi, j, GenerateSync(irg, pred_block, &pred_sets[i]));
523 static void Detotalise(ir_graph* irg)
525 ir_node* end_block = get_irg_end_block(irg);
526 size_t npreds = get_Block_n_cfgpreds(end_block);
529 unfinished_phis = xmalloc(sizeof(*unfinished_phis) * count_addrs);
530 for (i = 0; i < count_addrs; i++) {
531 unfinished_phis[i] = NULL;
534 for (i = 0; i < npreds; i++) {
535 ir_node* pred = get_Block_cfgpred(end_block, i);
536 assert(is_Return(pred));
537 DB((dbg, LEVEL_2, "===> Starting memory walk at %+F\n", pred));
538 WalkMem(irg, pred, NULL);
542 xfree(unfinished_phis);
546 static void AddSyncPreds(ir_nodeset_t* preds, ir_node* sync)
548 size_t n = get_Sync_n_preds(sync);
551 for (i = 0; i < n; i++) {
552 ir_node* pred = get_Sync_pred(sync, i);
554 AddSyncPreds(preds, pred);
556 ir_nodeset_insert(preds, pred);
562 static void NormaliseSync(ir_node* node, void* env)
565 ir_nodeset_iterator_t iter;
570 if (!is_Sync(node)) return;
572 ir_nodeset_init(&preds);
573 AddSyncPreds(&preds, node);
575 count_preds = ir_nodeset_size(&preds);
576 if (count_preds != get_Sync_n_preds(node)) {
577 NEW_ARR_A(ir_node*, in, count_preds);
578 ir_nodeset_iterator_init(&iter, &preds);
579 for (i = 0; i < count_preds; i++) {
580 ir_node* pred = ir_nodeset_iterator_next(&iter);
581 assert(pred != NULL);
584 set_irn_in(node, count_preds, in);
587 ir_nodeset_destroy(&preds);
591 void opt_ldst2(ir_graph* irg)
593 FIRM_DBG_REGISTER(dbg, "firm.opt.ldst2");
594 DB((dbg, LEVEL_1, "===> Performing load/store optimisation on %+F\n", irg));
596 normalize_one_return(irg);
600 if (1 /* XXX */ || get_opt_alias_analysis()) {
601 assure_irg_address_taken_computed(irg);
602 assure_irp_globals_address_taken_computed();
606 CollectAddresses(irg);
607 if (count_addrs == 0) return;
609 irg_block_walk_graph(irg, AliasSetAdder, NULL, NULL);
610 inc_irg_block_visited(irg);
611 SetStartAddressesTop(irg);
614 dump_ir_block_graph(irg, "-fluffig");
616 irg_block_walk_graph(irg, AliasSetDestroyer, NULL, NULL);
617 obstack_free(&obst, NULL);
619 normalize_proj_nodes(irg);
620 irg_walk_graph(irg, NormaliseSync, NULL, NULL);
621 optimize_graph_df(irg);
622 irg_walk_graph(irg, NormaliseSync, NULL, NULL);