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 Driver for the chordal register allocator.
23 * @author Sebastian Hack
39 #include "firm_config.h"
41 #include <libcore/lc_opts.h>
42 #include <libcore/lc_opts_enum.h>
43 #include <libcore/lc_timing.h>
47 #include "irgraph_t.h"
48 #include "irprintf_t.h"
60 #include "iredges_t.h"
62 #include "bechordal_t.h"
64 #include "bejavacoal.h"
67 #include "besched_t.h"
71 #include "beifg_impl.h"
73 #include "bestatevent.h"
80 #include "bespillbelady.h"
81 #include "bespillmorgan.h"
82 #include "bespillslots.h"
83 #include "bespilloptions.h"
87 #include "bespillremat.h"
90 #include "bejavacoal.h"
91 #include "becopystat.h"
92 #include "becopyopt.h"
93 #include "bessadestr.h"
97 static be_ra_chordal_opts_t options = {
99 BE_CH_LOWER_PERM_SWAP,
103 typedef struct _post_spill_env_t {
104 be_chordal_env_t cenv;
106 const arch_register_class_t *cls;
107 double pre_spill_cost;
110 static be_ra_timer_t ra_timer = {
124 static const lc_opt_enum_int_items_t lower_perm_items[] = {
125 { "copy", BE_CH_LOWER_PERM_COPY },
126 { "swap", BE_CH_LOWER_PERM_SWAP },
130 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
134 static const lc_opt_enum_int_items_t dump_items[] = {
135 { "none", BE_CH_DUMP_NONE },
136 { "spill", BE_CH_DUMP_SPILL },
137 { "live", BE_CH_DUMP_LIVE },
138 { "color", BE_CH_DUMP_COLOR },
139 { "copymin", BE_CH_DUMP_COPYMIN },
140 { "ssadestr", BE_CH_DUMP_SSADESTR },
141 { "tree", BE_CH_DUMP_TREE_INTV },
142 { "constr", BE_CH_DUMP_CONSTR },
143 { "lower", BE_CH_DUMP_LOWER },
144 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
145 { "appel", BE_CH_DUMP_APPEL },
146 { "all", BE_CH_DUMP_ALL },
150 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
151 { "off", BE_CH_VRFY_OFF },
152 { "warn", BE_CH_VRFY_WARN },
153 { "assert", BE_CH_VRFY_ASSERT },
157 static lc_opt_enum_int_var_t lower_perm_var = {
158 &options.lower_perm_opt, lower_perm_items
161 static lc_opt_enum_int_var_t dump_var = {
162 &options.dump_flags, dump_items
165 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
166 &options.vrfy_option, be_ch_vrfy_items
169 static const lc_opt_table_entry_t be_chordal_options[] = {
170 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
171 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
172 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
176 static void dump(unsigned mask, ir_graph *irg,
177 const arch_register_class_t *cls,
179 void (*dump_func)(ir_graph *, const char *))
181 if((options.dump_flags & mask) == mask) {
184 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
185 be_dump(irg, buf, dump_func);
188 be_dump(irg, suffix, dump_func);
193 * Checks for every reload if it's user can perform the load on itself.
195 static void memory_operand_walker(ir_node *irn, void *env) {
196 be_chordal_env_t *cenv = env;
197 const arch_env_t *aenv = cenv->birg->main_env->arch_env;
198 const ir_edge_t *edge, *ne;
202 if (! be_is_Reload(irn))
205 /* only use memory operands, if the reload is only used by 1 node */
206 if(get_irn_n_edges(irn) > 1)
209 spill = be_get_Reload_mem(irn);
210 block = get_nodes_block(irn);
212 foreach_out_edge_safe(irn, edge, ne) {
213 ir_node *src = get_edge_src_irn(edge);
214 int pos = get_edge_src_pos(edge);
216 assert(src && "outedges broken!");
218 if (get_nodes_block(src) == block && arch_possible_memory_operand(aenv, src, pos)) {
219 arch_perform_memory_operand(aenv, src, spill, pos);
223 /* kill the Reload */
224 if (get_irn_n_edges(irn) == 0) {
226 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
227 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
232 * Starts a walk for memory operands if supported by the backend.
234 static INLINE void check_for_memory_operands(be_chordal_env_t *chordal_env) {
235 irg_walk_graph(chordal_env->irg, NULL, memory_operand_walker, chordal_env);
239 * Sorry for doing stats again...
241 typedef struct _node_stat_t {
242 unsigned int n_phis; /**< Phis of the current register class. */
243 unsigned int n_mem_phis; /**< Memory Phis (Phis with spill operands). */
244 unsigned int n_copies; /**< Copies */
245 unsigned int n_perms; /**< Perms */
246 unsigned int n_spills; /**< Spill nodes */
247 unsigned int n_reloads; /**< Reloads */
250 struct node_stat_walker {
252 const arch_env_t *arch_env;
254 const arch_register_class_t *cls;
257 static void node_stat_walker(ir_node *irn, void *data)
259 struct node_stat_walker *env = data;
260 const arch_env_t *aenv = env->arch_env;
262 if (arch_irn_consider_in_reg_alloc(aenv, env->cls, irn)) {
264 /* if the node is a normal phi */
268 else if(arch_irn_classify(aenv, irn) & arch_irn_class_spill)
269 ++env->stat->n_spills;
271 else if(arch_irn_classify(aenv, irn) & arch_irn_class_reload)
272 ++env->stat->n_reloads;
274 else if(arch_irn_classify(aenv, irn) & arch_irn_class_copy)
275 ++env->stat->n_copies;
277 else if(arch_irn_classify(aenv, irn) & arch_irn_class_perm)
278 ++env->stat->n_perms;
281 /* a mem phi is a PhiM with a mem phi operand or a Spill operand */
282 else if(is_Phi(irn) && get_irn_mode(irn) == mode_M) {
285 for(i = get_irn_arity(irn) - 1; i >= 0; --i) {
286 ir_node *op = get_irn_n(irn, i);
288 if((is_Phi(op) && bitset_contains_irn(env->mem_phis, op)) || (arch_irn_classify(aenv, op) & arch_irn_class_spill)) {
289 bitset_add_irn(env->mem_phis, irn);
290 env->stat->n_mem_phis++;
297 static void node_stats(be_irg_t *birg, const arch_register_class_t *cls, node_stat_t *stat)
299 struct node_stat_walker env;
301 memset(stat, 0, sizeof(stat[0]));
302 env.arch_env = birg->main_env->arch_env;
303 env.mem_phis = bitset_irg_malloc(birg->irg);
306 irg_walk_graph(birg->irg, NULL, node_stat_walker, &env);
307 bitset_free(env.mem_phis);
310 static void insn_count_walker(ir_node *irn, void *data)
314 switch(get_irn_opcode(irn)) {
325 static unsigned int count_insns(ir_graph *irg)
328 irg_walk_graph(irg, insn_count_walker, NULL, &cnt);
333 * Initialize all timers.
335 static void be_init_timer(be_options_t *main_opts)
337 if (main_opts->timing == BE_TIME_ON) {
338 ra_timer.t_prolog = lc_timer_register("ra_prolog", "regalloc prolog");
339 ra_timer.t_epilog = lc_timer_register("ra_epilog", "regalloc epilog");
340 ra_timer.t_live = lc_timer_register("ra_liveness", "be liveness");
341 ra_timer.t_spill = lc_timer_register("ra_spill", "spiller");
342 ra_timer.t_spillslots = lc_timer_register("ra_spillslots", "spillslots");
343 ra_timer.t_color = lc_timer_register("ra_color", "graph coloring");
344 ra_timer.t_ifg = lc_timer_register("ra_ifg", "interference graph");
345 ra_timer.t_copymin = lc_timer_register("ra_copymin", "copy minimization");
346 ra_timer.t_ssa = lc_timer_register("ra_ssadestr", "ssa destruction");
347 ra_timer.t_verify = lc_timer_register("ra_verify", "graph verification");
348 ra_timer.t_other = lc_timer_register("ra_other", "other time");
350 LC_STOP_AND_RESET_TIMER(ra_timer.t_prolog);
351 LC_STOP_AND_RESET_TIMER(ra_timer.t_epilog);
352 LC_STOP_AND_RESET_TIMER(ra_timer.t_live);
353 LC_STOP_AND_RESET_TIMER(ra_timer.t_spill);
354 LC_STOP_AND_RESET_TIMER(ra_timer.t_spillslots);
355 LC_STOP_AND_RESET_TIMER(ra_timer.t_color);
356 LC_STOP_AND_RESET_TIMER(ra_timer.t_ifg);
357 LC_STOP_AND_RESET_TIMER(ra_timer.t_copymin);
358 LC_STOP_AND_RESET_TIMER(ra_timer.t_ssa);
359 LC_STOP_AND_RESET_TIMER(ra_timer.t_verify);
360 LC_STOP_AND_RESET_TIMER(ra_timer.t_other);
362 global_ra_timer = &ra_timer;
366 #define BE_TIMER_INIT(main_opts) be_init_timer(main_opts)
368 #define BE_TIMER_PUSH(timer) \
369 if (main_opts->timing == BE_TIME_ON) { \
370 if (! lc_timer_push(timer)) { \
371 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
372 assert(!"Timer already on stack, cannot be pushed twice."); \
373 else if (options.vrfy_option == BE_CH_VRFY_WARN) \
374 fprintf(stderr, "Timer %s already on stack, cannot be pushed twice.\n", \
375 lc_timer_get_name(timer)); \
378 #define BE_TIMER_POP(timer) \
379 if (main_opts->timing == BE_TIME_ON) { \
380 lc_timer_t *tmp = lc_timer_pop(); \
381 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
382 assert(tmp == timer && "Attempt to pop wrong timer."); \
383 else if (options.vrfy_option == BE_CH_VRFY_WARN && tmp != timer) \
384 fprintf(stderr, "Attempt to pop wrong timer. %s is on stack, trying to pop %s.\n", \
385 lc_timer_get_name(tmp), lc_timer_get_name(timer)); \
390 * Perform things which need to be done per register class before spilling.
392 static void pre_spill(const arch_isa_t *isa, int cls_idx, post_spill_env_t *pse) {
393 be_chordal_env_t *chordal_env = &pse->cenv;
394 be_irg_t *birg = pse->birg;
395 node_stat_t node_stat;
397 pse->cls = arch_isa_get_reg_class(isa, cls_idx);
398 chordal_env->cls = pse->cls;
399 chordal_env->border_heads = pmap_create();
400 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
402 #ifdef FIRM_STATISTICS
403 if (be_stat_ev_is_active()) {
404 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
405 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
407 /* perform some node statistics. */
408 node_stats(birg, pse->cls, &node_stat);
409 be_stat_ev("phis_before_spill", node_stat.n_phis);
411 #endif /* FIRM_STATISTICS */
413 /* put all ignore registers into the ignore register set. */
414 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
416 be_pre_spill_prepare_constr(chordal_env);
417 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
419 #ifdef FIRM_STATISTICS
420 if (be_stat_ev_is_active()) {
421 pse->pre_spill_cost = be_estimate_irg_costs(birg->irg,
422 birg->main_env->arch_env, birg->exec_freq);
425 #endif /* FIRM_STATISTICS */
429 * Perform things which need to be done per register class after spilling.
431 static void post_spill(post_spill_env_t *pse, int iteration) {
432 be_chordal_env_t *chordal_env = &pse->cenv;
433 be_irg_t *birg = pse->birg;
434 ir_graph *irg = birg->irg;
435 const be_main_env_t *main_env = birg->main_env;
436 be_options_t *main_opts = main_env->options;
437 node_stat_t node_stat;
438 int colors_n = arch_register_class_n_regs(chordal_env->cls);
439 int allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
441 /* some special classes contain only ignore regs, no work to be done */
442 if (allocatable_regs > 0) {
444 #ifdef FIRM_STATISTICS
445 if (be_stat_ev_is_active()) {
446 double spillcosts = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost;
448 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
449 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
451 be_stat_ev_l("spillcosts", (long) spillcosts);
453 node_stats(birg, pse->cls, &node_stat);
454 be_stat_ev("phis_after_spill", node_stat.n_phis);
455 be_stat_ev("mem_phis", node_stat.n_mem_phis);
456 be_stat_ev("reloads", node_stat.n_reloads);
457 be_stat_ev("spills", node_stat.n_spills);
459 #endif /* FIRM_STATISTICS */
462 If we have a backend provided spiller, post spill is
463 called in a loop after spilling for each register class.
464 But we only need to fix stack nodes once in this case.
466 if (iteration == 0) {
467 check_for_memory_operands(chordal_env);
468 be_abi_fix_stack_nodes(birg->abi);
471 BE_TIMER_PUSH(ra_timer.t_verify);
473 /* verify schedule and register pressure */
474 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
475 be_verify_schedule(birg);
476 be_verify_register_pressure(birg, pse->cls, irg);
478 else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
479 assert(be_verify_schedule(birg) && "Schedule verification failed");
480 assert(be_verify_register_pressure(birg, pse->cls, irg)
481 && "Register pressure verification failed");
483 BE_TIMER_POP(ra_timer.t_verify);
485 /* Color the graph. */
486 BE_TIMER_PUSH(ra_timer.t_color);
487 be_ra_chordal_color(chordal_env);
488 BE_TIMER_POP(ra_timer.t_color);
490 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
492 /* Create the ifg with the selected flavor */
493 BE_TIMER_PUSH(ra_timer.t_ifg);
494 chordal_env->ifg = be_create_ifg(chordal_env);
495 BE_TIMER_POP(ra_timer.t_ifg);
497 #ifdef FIRM_STATISTICS
498 if (be_stat_ev_is_active()) {
501 be_ifg_stat(birg, chordal_env->ifg, &stat);
502 be_stat_ev("ifg_nodes", stat.n_nodes);
503 be_stat_ev("ifg_edges", stat.n_edges);
504 be_stat_ev("ifg_comps", stat.n_comps);
506 node_stats(birg, pse->cls, &node_stat);
507 be_stat_ev("perms_before_coal", node_stat.n_perms);
508 be_stat_ev("copies_before_coal", node_stat.n_copies);
510 #endif /* FIRM_STATISTICS */
512 /* copy minimization */
513 BE_TIMER_PUSH(ra_timer.t_copymin);
514 co_driver(chordal_env);
515 BE_TIMER_POP(ra_timer.t_copymin);
517 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
519 BE_TIMER_PUSH(ra_timer.t_ssa);
521 /* ssa destruction */
522 be_ssa_destruction(chordal_env);
524 BE_TIMER_POP(ra_timer.t_ssa);
526 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
528 BE_TIMER_PUSH(ra_timer.t_verify);
529 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
530 be_ssa_destruction_check(chordal_env);
532 BE_TIMER_POP(ra_timer.t_verify);
534 #ifdef FIRM_STATISTICS
535 if (be_stat_ev_is_active()) {
536 node_stats(birg, pse->cls, &node_stat);
537 be_stat_ev("perms_after_coal", node_stat.n_perms);
538 be_stat_ev("copies_after_coal", node_stat.n_copies);
541 #endif /* FIRM_STATISTICS */
543 /* the ifg exists only if there are allocatable regs */
544 be_ifg_free(chordal_env->ifg);
547 /* free some always allocated data structures */
548 pmap_destroy(chordal_env->border_heads);
549 bitset_free(chordal_env->ignore_colors);
553 * Performs chordal register allocation for each register class on given irg.
555 * @param birg Backend irg object
556 * @return Structure containing timer for the single phases or NULL if no timing requested.
558 static void be_ra_chordal_main(be_irg_t *birg)
560 const be_main_env_t *main_env = birg->main_env;
561 const arch_isa_t *isa = arch_env_get_isa(main_env->arch_env);
562 ir_graph *irg = birg->irg;
563 be_options_t *main_opts = main_env->options;
565 be_chordal_env_t chordal_env;
568 BE_TIMER_INIT(main_opts);
569 BE_TIMER_PUSH(ra_timer.t_other);
570 BE_TIMER_PUSH(ra_timer.t_prolog);
572 be_assure_dom_front(birg);
573 be_assure_liveness(birg);
575 chordal_env.obst = &obst;
576 chordal_env.opts = &options;
577 chordal_env.irg = irg;
578 chordal_env.birg = birg;
579 chordal_env.border_heads = NULL;
580 chordal_env.ifg = NULL;
581 chordal_env.ignore_colors = NULL;
585 BE_TIMER_POP(ra_timer.t_prolog);
587 be_stat_ev("insns_before", count_insns(irg));
589 if (! arch_code_generator_has_spiller(birg->cg)) {
590 /* use one of the generic spiller */
592 /* Perform the following for each register class. */
593 for (j = 0, m = arch_isa_get_n_reg_class(isa); j < m; ++j) {
594 post_spill_env_t pse;
596 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
598 pre_spill(isa, j, &pse);
600 BE_TIMER_PUSH(ra_timer.t_spill);
601 be_do_spill(birg, pse.cls);
602 BE_TIMER_POP(ra_timer.t_spill);
604 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill", dump_ir_block_graph_sched);
609 post_spill_env_t *pse;
611 /* the backend has it's own spiller */
612 m = arch_isa_get_n_reg_class(isa);
614 pse = alloca(m * sizeof(pse[0]));
616 for (j = 0; j < m; ++j) {
617 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
619 pre_spill(isa, j, &pse[j]);
622 BE_TIMER_PUSH(ra_timer.t_spill);
623 arch_code_generator_spill(birg->cg, birg);
624 BE_TIMER_POP(ra_timer.t_spill);
625 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
627 for (j = 0; j < m; ++j) {
628 post_spill(&pse[j], j);
632 BE_TIMER_PUSH(ra_timer.t_epilog);
633 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
634 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
636 obstack_free(&obst, NULL);
637 be_invalidate_liveness(birg);
638 BE_TIMER_POP(ra_timer.t_epilog);
640 BE_TIMER_POP(ra_timer.t_other);
642 be_stat_ev("insns_after", count_insns(irg));
647 static be_ra_t be_ra_chordal_allocator = {
651 void be_init_chordal_main(void)
653 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
654 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
655 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
657 lc_opt_add_table(chordal_grp, be_chordal_options);
659 be_register_allocator("chordal", &be_ra_chordal_allocator);
662 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);