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,
105 typedef struct _post_spill_env_t {
106 be_chordal_env_t cenv;
108 const arch_register_class_t *cls;
109 double pre_spill_cost;
112 static be_ra_timer_t ra_timer = {
126 static const lc_opt_enum_int_items_t lower_perm_items[] = {
127 { "copy", BE_CH_LOWER_PERM_COPY },
128 { "swap", BE_CH_LOWER_PERM_SWAP },
132 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
136 static const lc_opt_enum_int_items_t dump_items[] = {
137 { "none", BE_CH_DUMP_NONE },
138 { "spill", BE_CH_DUMP_SPILL },
139 { "live", BE_CH_DUMP_LIVE },
140 { "color", BE_CH_DUMP_COLOR },
141 { "copymin", BE_CH_DUMP_COPYMIN },
142 { "ssadestr", BE_CH_DUMP_SSADESTR },
143 { "tree", BE_CH_DUMP_TREE_INTV },
144 { "constr", BE_CH_DUMP_CONSTR },
145 { "lower", BE_CH_DUMP_LOWER },
146 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
147 { "appel", BE_CH_DUMP_APPEL },
148 { "all", BE_CH_DUMP_ALL },
152 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
153 { "off", BE_CH_VRFY_OFF },
154 { "warn", BE_CH_VRFY_WARN },
155 { "assert", BE_CH_VRFY_ASSERT },
159 static lc_opt_enum_int_var_t lower_perm_var = {
160 &options.lower_perm_opt, lower_perm_items
163 static lc_opt_enum_int_var_t dump_var = {
164 &options.dump_flags, dump_items
167 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
168 &options.vrfy_option, be_ch_vrfy_items
171 static const lc_opt_table_entry_t be_chordal_options[] = {
172 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
173 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
174 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
178 static void dump(unsigned mask, ir_graph *irg,
179 const arch_register_class_t *cls,
181 void (*dump_func)(ir_graph *, const char *))
183 if((options.dump_flags & mask) == mask) {
186 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
187 be_dump(irg, buf, dump_func);
190 be_dump(irg, suffix, dump_func);
195 * Checks for every reload if it's user can perform the load on itself.
197 static void memory_operand_walker(ir_node *irn, void *env) {
198 be_chordal_env_t *cenv = env;
199 const arch_env_t *aenv = cenv->birg->main_env->arch_env;
200 const ir_edge_t *edge, *ne;
204 if (! be_is_Reload(irn))
207 /* only use memory operands, if the reload is only used by 1 node */
208 if(get_irn_n_edges(irn) > 1)
211 spill = be_get_Reload_mem(irn);
212 block = get_nodes_block(irn);
214 foreach_out_edge_safe(irn, edge, ne) {
215 ir_node *src = get_edge_src_irn(edge);
216 int pos = get_edge_src_pos(edge);
218 assert(src && "outedges broken!");
220 if (get_nodes_block(src) == block && arch_possible_memory_operand(aenv, src, pos)) {
221 arch_perform_memory_operand(aenv, src, spill, pos);
225 /* kill the Reload */
226 if (get_irn_n_edges(irn) == 0) {
228 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
229 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
234 * Starts a walk for memory operands if supported by the backend.
236 static INLINE void check_for_memory_operands(be_chordal_env_t *chordal_env) {
237 irg_walk_graph(chordal_env->irg, NULL, memory_operand_walker, chordal_env);
241 * Sorry for doing stats again...
243 typedef struct _node_stat_t {
244 unsigned int n_phis; /**< Phis of the current register class. */
245 unsigned int n_mem_phis; /**< Memory Phis (Phis with spill operands). */
246 unsigned int n_copies; /**< Copies */
247 unsigned int n_perms; /**< Perms */
248 unsigned int n_spills; /**< Spill nodes */
249 unsigned int n_reloads; /**< Reloads */
252 struct node_stat_walker {
254 const arch_env_t *arch_env;
256 const arch_register_class_t *cls;
259 static void node_stat_walker(ir_node *irn, void *data)
261 struct node_stat_walker *env = data;
262 const arch_env_t *aenv = env->arch_env;
264 if (arch_irn_consider_in_reg_alloc(aenv, env->cls, irn)) {
266 /* if the node is a normal phi */
270 else if(arch_irn_classify(aenv, irn) & arch_irn_class_spill)
271 ++env->stat->n_spills;
273 else if(arch_irn_classify(aenv, irn) & arch_irn_class_reload)
274 ++env->stat->n_reloads;
276 else if(arch_irn_classify(aenv, irn) & arch_irn_class_copy)
277 ++env->stat->n_copies;
279 else if(arch_irn_classify(aenv, irn) & arch_irn_class_perm)
280 ++env->stat->n_perms;
283 /* a mem phi is a PhiM with a mem phi operand or a Spill operand */
284 else if(is_Phi(irn) && get_irn_mode(irn) == mode_M) {
287 for(i = get_irn_arity(irn) - 1; i >= 0; --i) {
288 ir_node *op = get_irn_n(irn, i);
290 if((is_Phi(op) && bitset_contains_irn(env->mem_phis, op)) || (arch_irn_classify(aenv, op) & arch_irn_class_spill)) {
291 bitset_add_irn(env->mem_phis, irn);
292 env->stat->n_mem_phis++;
299 static void node_stats(be_irg_t *birg, const arch_register_class_t *cls, node_stat_t *stat)
301 struct node_stat_walker env;
303 memset(stat, 0, sizeof(stat[0]));
304 env.arch_env = birg->main_env->arch_env;
305 env.mem_phis = bitset_irg_malloc(birg->irg);
308 irg_walk_graph(birg->irg, NULL, node_stat_walker, &env);
309 bitset_free(env.mem_phis);
312 static void insn_count_walker(ir_node *irn, void *data)
316 switch(get_irn_opcode(irn)) {
327 static unsigned int count_insns(ir_graph *irg)
330 irg_walk_graph(irg, insn_count_walker, NULL, &cnt);
335 * Initialize all timers.
337 static void be_init_timer(be_options_t *main_opts)
339 if (main_opts->timing == BE_TIME_ON) {
340 ra_timer.t_prolog = lc_timer_register("ra_prolog", "regalloc prolog");
341 ra_timer.t_epilog = lc_timer_register("ra_epilog", "regalloc epilog");
342 ra_timer.t_live = lc_timer_register("ra_liveness", "be liveness");
343 ra_timer.t_spill = lc_timer_register("ra_spill", "spiller");
344 ra_timer.t_spillslots = lc_timer_register("ra_spillslots", "spillslots");
345 ra_timer.t_color = lc_timer_register("ra_color", "graph coloring");
346 ra_timer.t_ifg = lc_timer_register("ra_ifg", "interference graph");
347 ra_timer.t_copymin = lc_timer_register("ra_copymin", "copy minimization");
348 ra_timer.t_ssa = lc_timer_register("ra_ssadestr", "ssa destruction");
349 ra_timer.t_verify = lc_timer_register("ra_verify", "graph verification");
350 ra_timer.t_other = lc_timer_register("ra_other", "other time");
352 LC_STOP_AND_RESET_TIMER(ra_timer.t_prolog);
353 LC_STOP_AND_RESET_TIMER(ra_timer.t_epilog);
354 LC_STOP_AND_RESET_TIMER(ra_timer.t_live);
355 LC_STOP_AND_RESET_TIMER(ra_timer.t_spill);
356 LC_STOP_AND_RESET_TIMER(ra_timer.t_spillslots);
357 LC_STOP_AND_RESET_TIMER(ra_timer.t_color);
358 LC_STOP_AND_RESET_TIMER(ra_timer.t_ifg);
359 LC_STOP_AND_RESET_TIMER(ra_timer.t_copymin);
360 LC_STOP_AND_RESET_TIMER(ra_timer.t_ssa);
361 LC_STOP_AND_RESET_TIMER(ra_timer.t_verify);
362 LC_STOP_AND_RESET_TIMER(ra_timer.t_other);
364 global_ra_timer = &ra_timer;
368 #define BE_TIMER_INIT(main_opts) be_init_timer(main_opts)
370 #define BE_TIMER_PUSH(timer) \
371 if (main_opts->timing == BE_TIME_ON) { \
372 if (! lc_timer_push(timer)) { \
373 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
374 assert(!"Timer already on stack, cannot be pushed twice."); \
375 else if (options.vrfy_option == BE_CH_VRFY_WARN) \
376 fprintf(stderr, "Timer %s already on stack, cannot be pushed twice.\n", \
377 lc_timer_get_name(timer)); \
380 #define BE_TIMER_POP(timer) \
381 if (main_opts->timing == BE_TIME_ON) { \
382 lc_timer_t *tmp = lc_timer_pop(); \
383 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
384 assert(tmp == timer && "Attempt to pop wrong timer."); \
385 else if (options.vrfy_option == BE_CH_VRFY_WARN && tmp != timer) \
386 fprintf(stderr, "Attempt to pop wrong timer. %s is on stack, trying to pop %s.\n", \
387 lc_timer_get_name(tmp), lc_timer_get_name(timer)); \
392 * Perform things which need to be done per register class before spilling.
394 static void pre_spill(const arch_isa_t *isa, int cls_idx, post_spill_env_t *pse) {
395 be_chordal_env_t *chordal_env = &pse->cenv;
396 be_irg_t *birg = pse->birg;
397 node_stat_t node_stat;
399 pse->cls = arch_isa_get_reg_class(isa, cls_idx);
400 chordal_env->cls = pse->cls;
401 chordal_env->border_heads = pmap_create();
402 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
404 #ifdef FIRM_STATISTICS
405 if (be_stat_ev_is_active()) {
406 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
407 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
409 /* perform some node statistics. */
410 node_stats(birg, pse->cls, &node_stat);
411 be_stat_ev("phis_before_spill", node_stat.n_phis);
413 #endif /* FIRM_STATISTICS */
415 /* put all ignore registers into the ignore register set. */
416 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
418 be_pre_spill_prepare_constr(chordal_env);
419 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
421 #ifdef FIRM_STATISTICS
422 if (be_stat_ev_is_active()) {
423 pse->pre_spill_cost = be_estimate_irg_costs(birg->irg,
424 birg->main_env->arch_env, birg->exec_freq);
427 #endif /* FIRM_STATISTICS */
431 * Perform things which need to be done per register class after spilling.
433 static void post_spill(post_spill_env_t *pse, int iteration) {
434 be_chordal_env_t *chordal_env = &pse->cenv;
435 be_irg_t *birg = pse->birg;
436 ir_graph *irg = birg->irg;
437 const be_main_env_t *main_env = birg->main_env;
438 be_options_t *main_opts = main_env->options;
439 node_stat_t node_stat;
440 int colors_n = arch_register_class_n_regs(chordal_env->cls);
441 int allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
443 /* some special classes contain only ignore regs, no work to be done */
444 if (allocatable_regs > 0) {
446 #ifdef FIRM_STATISTICS
447 if (be_stat_ev_is_active()) {
448 double spillcosts = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost;
450 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
451 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
453 be_stat_ev_l("spillcosts", (long) spillcosts);
455 node_stats(birg, pse->cls, &node_stat);
456 be_stat_ev("phis_after_spill", node_stat.n_phis);
457 be_stat_ev("mem_phis", node_stat.n_mem_phis);
458 be_stat_ev("reloads", node_stat.n_reloads);
459 be_stat_ev("spills", node_stat.n_spills);
461 #endif /* FIRM_STATISTICS */
464 If we have a backend provided spiller, post spill is
465 called in a loop after spilling for each register class.
466 But we only need to fix stack nodes once in this case.
468 if (iteration == 0) {
469 check_for_memory_operands(chordal_env);
470 be_abi_fix_stack_nodes(birg->abi);
473 BE_TIMER_PUSH(ra_timer.t_verify);
475 /* verify schedule and register pressure */
476 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
477 be_verify_schedule(birg);
478 be_verify_register_pressure(birg, pse->cls, irg);
480 else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
481 assert(be_verify_schedule(birg) && "Schedule verification failed");
482 assert(be_verify_register_pressure(birg, pse->cls, irg)
483 && "Register pressure verification failed");
485 BE_TIMER_POP(ra_timer.t_verify);
487 /* Color the graph. */
488 BE_TIMER_PUSH(ra_timer.t_color);
489 be_ra_chordal_color(chordal_env);
490 BE_TIMER_POP(ra_timer.t_color);
492 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
494 /* Create the ifg with the selected flavor */
495 BE_TIMER_PUSH(ra_timer.t_ifg);
496 chordal_env->ifg = be_create_ifg(chordal_env);
497 BE_TIMER_POP(ra_timer.t_ifg);
499 #ifdef FIRM_STATISTICS
500 if (be_stat_ev_is_active()) {
503 be_ifg_stat(birg, chordal_env->ifg, &stat);
504 be_stat_ev("ifg_nodes", stat.n_nodes);
505 be_stat_ev("ifg_edges", stat.n_edges);
506 be_stat_ev("ifg_comps", stat.n_comps);
508 node_stats(birg, pse->cls, &node_stat);
509 be_stat_ev("perms_before_coal", node_stat.n_perms);
510 be_stat_ev("copies_before_coal", node_stat.n_copies);
512 #endif /* FIRM_STATISTICS */
514 /* copy minimization */
515 BE_TIMER_PUSH(ra_timer.t_copymin);
516 co_driver(chordal_env);
517 BE_TIMER_POP(ra_timer.t_copymin);
519 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
521 BE_TIMER_PUSH(ra_timer.t_ssa);
523 /* ssa destruction */
524 be_ssa_destruction(chordal_env);
526 BE_TIMER_POP(ra_timer.t_ssa);
528 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
530 BE_TIMER_PUSH(ra_timer.t_verify);
531 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
532 be_ssa_destruction_check(chordal_env);
534 BE_TIMER_POP(ra_timer.t_verify);
536 #ifdef FIRM_STATISTICS
537 if (be_stat_ev_is_active()) {
538 node_stats(birg, pse->cls, &node_stat);
539 be_stat_ev("perms_after_coal", node_stat.n_perms);
540 be_stat_ev("copies_after_coal", node_stat.n_copies);
543 #endif /* FIRM_STATISTICS */
545 /* the ifg exists only if there are allocatable regs */
546 be_ifg_free(chordal_env->ifg);
549 /* free some always allocated data structures */
550 pmap_destroy(chordal_env->border_heads);
551 bitset_free(chordal_env->ignore_colors);
555 * Performs chordal register allocation for each register class on given irg.
557 * @param birg Backend irg object
558 * @return Structure containing timer for the single phases or NULL if no timing requested.
560 static void be_ra_chordal_main(be_irg_t *birg)
562 const be_main_env_t *main_env = birg->main_env;
563 const arch_isa_t *isa = arch_env_get_isa(main_env->arch_env);
564 ir_graph *irg = birg->irg;
565 be_options_t *main_opts = main_env->options;
567 be_chordal_env_t chordal_env;
570 BE_TIMER_INIT(main_opts);
571 BE_TIMER_PUSH(ra_timer.t_other);
572 BE_TIMER_PUSH(ra_timer.t_prolog);
574 be_assure_dom_front(birg);
575 be_assure_liveness(birg);
577 chordal_env.obst = &obst;
578 chordal_env.opts = &options;
579 chordal_env.irg = irg;
580 chordal_env.birg = birg;
581 chordal_env.border_heads = NULL;
582 chordal_env.ifg = NULL;
583 chordal_env.ignore_colors = NULL;
587 BE_TIMER_POP(ra_timer.t_prolog);
589 be_stat_ev("insns_before", count_insns(irg));
591 if (! arch_code_generator_has_spiller(birg->cg)) {
592 /* use one of the generic spiller */
594 /* Perform the following for each register class. */
595 for (j = 0, m = arch_isa_get_n_reg_class(isa); j < m; ++j) {
596 post_spill_env_t pse;
598 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
600 pre_spill(isa, j, &pse);
602 BE_TIMER_PUSH(ra_timer.t_spill);
603 be_do_spill(birg, pse.cls);
604 BE_TIMER_POP(ra_timer.t_spill);
606 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill", dump_ir_block_graph_sched);
611 post_spill_env_t *pse;
613 /* the backend has it's own spiller */
614 m = arch_isa_get_n_reg_class(isa);
616 pse = alloca(m * sizeof(pse[0]));
618 for (j = 0; j < m; ++j) {
619 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
621 pre_spill(isa, j, &pse[j]);
624 BE_TIMER_PUSH(ra_timer.t_spill);
625 arch_code_generator_spill(birg->cg, birg);
626 BE_TIMER_POP(ra_timer.t_spill);
627 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
629 for (j = 0; j < m; ++j) {
630 post_spill(&pse[j], j);
634 BE_TIMER_PUSH(ra_timer.t_epilog);
635 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
636 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
638 obstack_free(&obst, NULL);
639 be_liveness_invalidate(be_get_birg_liveness(birg));
640 BE_TIMER_POP(ra_timer.t_epilog);
642 BE_TIMER_POP(ra_timer.t_other);
644 be_stat_ev("insns_after", count_insns(irg));
649 static be_ra_t be_ra_chordal_allocator = {
653 void be_init_chordal_main(void)
655 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
656 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
657 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
659 lc_opt_add_table(chordal_grp, be_chordal_options);
661 be_register_allocator("chordal", &be_ra_chordal_allocator);
664 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);