2 * @file bechordal_main.c
4 * @author Sebastian Hack
7 * Copyright (C) 2005-2006 Universitaet Karlsruhe
8 * Released under the GPL
10 * Driver for the chordal register allocator.
23 #include "firm_config.h"
25 #include <libcore/lc_opts.h>
26 #include <libcore/lc_opts_enum.h>
27 #include <libcore/lc_timing.h>
31 #include "irgraph_t.h"
32 #include "irprintf_t.h"
45 #include "bechordal_t.h"
47 #include "bejavacoal.h"
50 #include "besched_t.h"
54 #include "beifg_impl.h"
56 #include "bestatevent.h"
60 #include "bespillbelady.h"
61 #include "bespillmorgan.h"
62 #include "bespillslots.h"
63 #include "bespilloptions.h"
67 #include "bespillremat.h"
70 #include "bejavacoal.h"
71 #include "becopystat.h"
72 #include "becopyopt.h"
73 #include "bessadestr.h"
77 static be_ra_chordal_opts_t options = {
79 BE_CH_LOWER_PERM_SWAP,
83 /** Enable extreme live range splitting. */
84 static int be_elr_split = 0;
86 typedef struct _post_spill_env_t {
87 be_chordal_env_t cenv;
89 const arch_register_class_t *cls;
90 double pre_spill_cost;
93 static be_ra_timer_t ra_timer = {
107 static const lc_opt_enum_int_items_t lower_perm_items[] = {
108 { "copy", BE_CH_LOWER_PERM_COPY },
109 { "swap", BE_CH_LOWER_PERM_SWAP },
113 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
117 static const lc_opt_enum_int_items_t dump_items[] = {
118 { "none", BE_CH_DUMP_NONE },
119 { "spill", BE_CH_DUMP_SPILL },
120 { "live", BE_CH_DUMP_LIVE },
121 { "color", BE_CH_DUMP_COLOR },
122 { "copymin", BE_CH_DUMP_COPYMIN },
123 { "ssadestr", BE_CH_DUMP_SSADESTR },
124 { "tree", BE_CH_DUMP_TREE_INTV },
125 { "constr", BE_CH_DUMP_CONSTR },
126 { "lower", BE_CH_DUMP_LOWER },
127 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
128 { "appel", BE_CH_DUMP_APPEL },
129 { "all", BE_CH_DUMP_ALL },
133 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
134 { "off", BE_CH_VRFY_OFF },
135 { "warn", BE_CH_VRFY_WARN },
136 { "assert", BE_CH_VRFY_ASSERT },
140 static lc_opt_enum_int_var_t lower_perm_var = {
141 &options.lower_perm_opt, lower_perm_items
144 static lc_opt_enum_int_var_t dump_var = {
145 &options.dump_flags, dump_items
148 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
149 &options.vrfy_option, be_ch_vrfy_items
152 static const lc_opt_table_entry_t be_chordal_options[] = {
153 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
154 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
155 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
156 LC_OPT_ENT_BOOL ("elrsplit", "enable extreme live range splitting", &be_elr_split),
160 static void dump(unsigned mask, ir_graph *irg,
161 const arch_register_class_t *cls,
163 void (*dump_func)(ir_graph *, const char *))
165 if((options.dump_flags & mask) == mask) {
168 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
169 be_dump(irg, buf, dump_func);
172 be_dump(irg, suffix, dump_func);
177 * Checks for every reload if it's user can perform the load on itself.
179 static void memory_operand_walker(ir_node *irn, void *env) {
180 be_chordal_env_t *cenv = env;
181 const arch_env_t *aenv = cenv->birg->main_env->arch_env;
182 const ir_edge_t *edge, *ne;
186 if (! be_is_Reload(irn))
189 /* only use memory operands, if the reload is only used by 1 node */
190 if(get_irn_n_edges(irn) > 1)
193 spill = be_get_Reload_mem(irn);
194 block = get_nodes_block(irn);
196 foreach_out_edge_safe(irn, edge, ne) {
197 ir_node *src = get_edge_src_irn(edge);
198 int pos = get_edge_src_pos(edge);
200 assert(src && "outedges broken!");
202 if (get_nodes_block(src) == block && arch_possible_memory_operand(aenv, src, pos)) {
203 DBG((cenv->dbg, LEVEL_3, "performing memory operand %+F at %+F\n", irn, src));
204 arch_perform_memory_operand(aenv, src, spill, pos);
208 /* kill the Reload */
209 if (get_irn_n_edges(irn) == 0) {
211 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
212 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
217 * Starts a walk for memory operands if supported by the backend.
219 static INLINE void check_for_memory_operands(be_chordal_env_t *chordal_env) {
220 irg_walk_graph(chordal_env->irg, NULL, memory_operand_walker, chordal_env);
224 * Sorry for doing stats again...
226 typedef struct _node_stat_t {
227 unsigned int n_phis; /**< Phis of the current register class. */
228 unsigned int n_mem_phis; /**< Memory Phis (Phis with spill operands). */
229 unsigned int n_copies; /**< Copies */
230 unsigned int n_perms; /**< Perms */
231 unsigned int n_spills; /**< Spill nodes */
232 unsigned int n_reloads; /**< Reloads */
235 struct node_stat_walker {
237 const arch_env_t *arch_env;
239 const arch_register_class_t *cls;
242 static void node_stat_walker(ir_node *irn, void *data)
244 struct node_stat_walker *env = data;
245 const arch_env_t *aenv = env->arch_env;
247 if (arch_irn_consider_in_reg_alloc(aenv, env->cls, irn)) {
249 /* if the node is a normal phi */
253 else if(arch_irn_classify(aenv, irn) & arch_irn_class_spill)
254 ++env->stat->n_spills;
256 else if(arch_irn_classify(aenv, irn) & arch_irn_class_reload)
257 ++env->stat->n_reloads;
259 else if(arch_irn_classify(aenv, irn) & arch_irn_class_copy)
260 ++env->stat->n_copies;
262 else if(arch_irn_classify(aenv, irn) & arch_irn_class_perm)
263 ++env->stat->n_perms;
266 /* a mem phi is a PhiM with a mem phi operand or a Spill operand */
267 else if(is_Phi(irn) && get_irn_mode(irn) == mode_M) {
270 for(i = get_irn_arity(irn) - 1; i >= 0; --i) {
271 ir_node *op = get_irn_n(irn, i);
273 if((is_Phi(op) && bitset_contains_irn(env->mem_phis, op)) || (arch_irn_classify(aenv, op) & arch_irn_class_spill)) {
274 bitset_add_irn(env->mem_phis, irn);
275 env->stat->n_mem_phis++;
282 static void node_stats(be_irg_t *birg, const arch_register_class_t *cls, node_stat_t *stat)
284 struct node_stat_walker env;
286 memset(stat, 0, sizeof(stat[0]));
287 env.arch_env = birg->main_env->arch_env;
288 env.mem_phis = bitset_irg_malloc(birg->irg);
291 irg_walk_graph(birg->irg, NULL, node_stat_walker, &env);
292 bitset_free(env.mem_phis);
295 static void insn_count_walker(ir_node *irn, void *data)
299 switch(get_irn_opcode(irn)) {
310 static unsigned int count_insns(ir_graph *irg)
313 irg_walk_graph(irg, insn_count_walker, NULL, &cnt);
318 * Initialize all timers.
320 static void be_init_timer(be_options_t *main_opts)
322 if (main_opts->timing == BE_TIME_ON) {
323 ra_timer.t_prolog = lc_timer_register("ra_prolog", "regalloc prolog");
324 ra_timer.t_epilog = lc_timer_register("ra_epilog", "regalloc epilog");
325 ra_timer.t_live = lc_timer_register("ra_liveness", "be liveness");
326 ra_timer.t_spill = lc_timer_register("ra_spill", "spiller");
327 ra_timer.t_spillslots = lc_timer_register("ra_spillslots", "spillslots");
328 ra_timer.t_color = lc_timer_register("ra_color", "graph coloring");
329 ra_timer.t_ifg = lc_timer_register("ra_ifg", "interference graph");
330 ra_timer.t_copymin = lc_timer_register("ra_copymin", "copy minimization");
331 ra_timer.t_ssa = lc_timer_register("ra_ssadestr", "ssa destruction");
332 ra_timer.t_verify = lc_timer_register("ra_verify", "graph verification");
333 ra_timer.t_other = lc_timer_register("ra_other", "other time");
335 LC_STOP_AND_RESET_TIMER(ra_timer.t_prolog);
336 LC_STOP_AND_RESET_TIMER(ra_timer.t_epilog);
337 LC_STOP_AND_RESET_TIMER(ra_timer.t_live);
338 LC_STOP_AND_RESET_TIMER(ra_timer.t_spill);
339 LC_STOP_AND_RESET_TIMER(ra_timer.t_spillslots);
340 LC_STOP_AND_RESET_TIMER(ra_timer.t_color);
341 LC_STOP_AND_RESET_TIMER(ra_timer.t_ifg);
342 LC_STOP_AND_RESET_TIMER(ra_timer.t_copymin);
343 LC_STOP_AND_RESET_TIMER(ra_timer.t_ssa);
344 LC_STOP_AND_RESET_TIMER(ra_timer.t_verify);
345 LC_STOP_AND_RESET_TIMER(ra_timer.t_other);
347 global_ra_timer = &ra_timer;
351 #define BE_TIMER_INIT(main_opts) be_init_timer(main_opts)
353 #define BE_TIMER_PUSH(timer) \
354 if (main_opts->timing == BE_TIME_ON) { \
355 if (! lc_timer_push(timer)) { \
356 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
357 assert(!"Timer already on stack, cannot be pushed twice."); \
358 else if (options.vrfy_option == BE_CH_VRFY_WARN) \
359 fprintf(stderr, "Timer %s already on stack, cannot be pushed twice.\n", \
360 lc_timer_get_name(timer)); \
363 #define BE_TIMER_POP(timer) \
364 if (main_opts->timing == BE_TIME_ON) { \
365 lc_timer_t *tmp = lc_timer_pop(); \
366 if (options.vrfy_option == BE_CH_VRFY_ASSERT) \
367 assert(tmp == timer && "Attempt to pop wrong timer."); \
368 else if (options.vrfy_option == BE_CH_VRFY_WARN && tmp != timer) \
369 fprintf(stderr, "Attempt to pop wrong timer. %s is on stack, trying to pop %s.\n", \
370 lc_timer_get_name(tmp), lc_timer_get_name(timer)); \
375 * Perform things which need to be done per register class before spilling.
377 static void pre_spill(const arch_isa_t *isa, int cls_idx, post_spill_env_t *pse) {
378 be_chordal_env_t *chordal_env = &pse->cenv;
379 be_irg_t *birg = pse->birg;
380 node_stat_t node_stat;
382 pse->cls = arch_isa_get_reg_class(isa, cls_idx);
383 chordal_env->cls = pse->cls;
384 chordal_env->border_heads = pmap_create();
385 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
387 #ifdef FIRM_STATISTICS
388 if (be_stat_ev_is_active()) {
389 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
390 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
392 /* perform some node statistics. */
393 node_stats(birg, pse->cls, &node_stat);
394 be_stat_ev("phis_before_spill", node_stat.n_phis);
396 #endif /* FIRM_STATISTICS */
398 /* put all ignore registers into the ignore register set. */
399 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
401 be_pre_spill_prepare_constr(chordal_env);
402 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
404 #ifdef FIRM_STATISTICS
405 if (be_stat_ev_is_active()) {
406 pse->pre_spill_cost = be_estimate_irg_costs(birg->irg,
407 birg->main_env->arch_env, birg->exec_freq);
410 #endif /* FIRM_STATISTICS */
414 * Perform things which need to be done per register class after spilling.
416 static void post_spill(post_spill_env_t *pse, int iteration) {
417 be_chordal_env_t *chordal_env = &pse->cenv;
418 be_irg_t *birg = pse->birg;
419 ir_graph *irg = birg->irg;
420 const be_main_env_t *main_env = birg->main_env;
421 be_options_t *main_opts = main_env->options;
422 static int splitted = 0;
423 node_stat_t node_stat;
425 #ifdef FIRM_STATISTICS
426 if (be_stat_ev_is_active()) {
427 double spillcosts = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost;
429 be_stat_tags[STAT_TAG_CLS] = pse->cls->name;
430 be_stat_ev_push(be_stat_tags, STAT_TAG_LAST, be_stat_file);
432 be_stat_ev_l("spillcosts", (long) spillcosts);
434 node_stats(birg, pse->cls, &node_stat);
435 be_stat_ev("phis_after_spill", node_stat.n_phis);
436 be_stat_ev("mem_phis", node_stat.n_mem_phis);
437 be_stat_ev("reloads", node_stat.n_reloads);
438 be_stat_ev("spills", node_stat.n_spills);
440 #endif /* FIRM_STATISTICS */
443 If we have a backend provided spiller, post spill is
444 called in a loop after spilling for each register class.
445 But we only need to fix stack nodes once in this case.
447 if (iteration == 0) {
448 check_for_memory_operands(chordal_env);
449 be_abi_fix_stack_nodes(birg->abi, birg->lv);
452 BE_TIMER_PUSH(ra_timer.t_verify);
454 /* verify schedule and register pressure */
455 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
456 be_verify_schedule(irg);
457 be_verify_register_pressure(birg, pse->cls, irg);
459 else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
460 assert(be_verify_schedule(irg) && "Schedule verification failed");
461 assert(be_verify_register_pressure(birg, pse->cls, irg)
462 && "Register pressure verification failed");
464 BE_TIMER_POP(ra_timer.t_verify);
466 if (be_elr_split && ! splitted) {
467 extreme_liverange_splitting(chordal_env);
471 /* Color the graph. */
472 BE_TIMER_PUSH(ra_timer.t_color);
473 be_ra_chordal_color(chordal_env);
474 BE_TIMER_POP(ra_timer.t_color);
476 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
478 /* Create the ifg with the selected flavor */
479 BE_TIMER_PUSH(ra_timer.t_ifg);
480 chordal_env->ifg = be_create_ifg(chordal_env);
481 BE_TIMER_POP(ra_timer.t_ifg);
483 #ifdef FIRM_STATISTICS
484 if (be_stat_ev_is_active()) {
487 be_ifg_stat(birg, chordal_env->ifg, &stat);
488 be_stat_ev("ifg_nodes", stat.n_nodes);
489 be_stat_ev("ifg_edges", stat.n_edges);
490 be_stat_ev("ifg_comps", stat.n_comps);
492 node_stats(birg, pse->cls, &node_stat);
493 be_stat_ev("perms_before_coal", node_stat.n_perms);
494 be_stat_ev("copies_before_coal", node_stat.n_copies);
496 #endif /* FIRM_STATISTICS */
498 /* copy minimization */
499 BE_TIMER_PUSH(ra_timer.t_copymin);
500 co_driver(chordal_env);
501 BE_TIMER_POP(ra_timer.t_copymin);
503 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
505 BE_TIMER_PUSH(ra_timer.t_ssa);
507 /* ssa destruction */
508 be_ssa_destruction(chordal_env);
510 BE_TIMER_POP(ra_timer.t_ssa);
512 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
514 BE_TIMER_PUSH(ra_timer.t_verify);
515 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
516 be_ssa_destruction_check(chordal_env);
518 BE_TIMER_POP(ra_timer.t_verify);
520 /* free some data structures */
521 be_ifg_free(chordal_env->ifg);
522 pmap_destroy(chordal_env->border_heads);
523 bitset_free(chordal_env->ignore_colors);
525 #ifdef FIRM_STATISTICS
526 if (be_stat_ev_is_active()) {
527 node_stats(birg, pse->cls, &node_stat);
528 be_stat_ev("perms_after_coal", node_stat.n_perms);
529 be_stat_ev("copies_after_coal", node_stat.n_copies);
532 #endif /* FIRM_STATISTICS */
536 * Performs chordal register allocation for each register class on given irg.
538 * @param birg Backend irg object
539 * @return Structure containing timer for the single phases or NULL if no timing requested.
541 static void be_ra_chordal_main(be_irg_t *birg)
543 const be_main_env_t *main_env = birg->main_env;
544 const arch_isa_t *isa = arch_env_get_isa(main_env->arch_env);
545 ir_graph *irg = birg->irg;
546 be_options_t *main_opts = main_env->options;
548 be_chordal_env_t chordal_env;
550 BE_TIMER_INIT(main_opts);
551 BE_TIMER_PUSH(ra_timer.t_other);
552 BE_TIMER_PUSH(ra_timer.t_prolog);
554 be_assure_dom_front(birg);
555 be_assure_liveness(birg);
557 chordal_env.opts = &options;
558 chordal_env.irg = irg;
559 chordal_env.birg = birg;
560 FIRM_DBG_REGISTER(chordal_env.dbg, "firm.be.chordal");
562 obstack_init(&chordal_env.obst);
564 BE_TIMER_POP(ra_timer.t_prolog);
566 be_stat_ev("insns_before", count_insns(irg));
568 if (! arch_code_generator_has_spiller(birg->cg)) {
569 /* use one of the generic spiller */
571 /* Perform the following for each register class. */
572 for (j = 0, m = arch_isa_get_n_reg_class(isa); j < m; ++j) {
573 post_spill_env_t pse;
575 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
577 pre_spill(isa, j, &pse);
579 BE_TIMER_PUSH(ra_timer.t_spill);
580 be_do_spill(birg, pse.cls);
581 BE_TIMER_POP(ra_timer.t_spill);
583 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill", dump_ir_block_graph_sched);
588 post_spill_env_t *pse;
590 /* the backend has it's own spiller */
591 m = arch_isa_get_n_reg_class(isa);
593 pse = alloca(m * sizeof(pse[0]));
595 for (j = 0; j < m; ++j) {
596 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
598 pre_spill(isa, j, &pse[j]);
601 BE_TIMER_PUSH(ra_timer.t_spill);
602 arch_code_generator_spill(birg->cg, birg);
603 BE_TIMER_POP(ra_timer.t_spill);
604 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
606 for (j = 0; j < m; ++j) {
607 post_spill(&pse[j], j);
611 BE_TIMER_PUSH(ra_timer.t_epilog);
612 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
613 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
615 obstack_free(&chordal_env.obst, NULL);
616 be_invalidate_liveness(birg);
617 BE_TIMER_POP(ra_timer.t_epilog);
619 BE_TIMER_POP(ra_timer.t_other);
621 be_stat_ev("insns_after", count_insns(irg));
626 static be_ra_t be_ra_chordal_allocator = {
630 void be_init_chordal(void)
632 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
633 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
634 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
636 lc_opt_add_table(chordal_grp, be_chordal_options);
638 be_register_allocator("chordal", &be_ra_chordal_allocator);
641 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal);