2 * Copyright (C) 1995-2008 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"
42 #include "lc_opts_enum.h"
46 #include "irgraph_t.h"
47 #include "irprintf_t.h"
59 #include "iredges_t.h"
61 #include "bechordal_t.h"
63 #include "bejavacoal.h"
66 #include "besched_t.h"
70 #include "beifg_impl.h"
72 #include "bestatevent.h"
79 #include "bespillslots.h"
80 #include "bespilloptions.h"
84 #include "bespillremat.h"
87 #include "bejavacoal.h"
88 #include "becopystat.h"
89 #include "becopyopt.h"
90 #include "bessadestr.h"
94 static be_ra_chordal_opts_t options = {
96 BE_CH_LOWER_PERM_SWAP,
102 typedef struct _post_spill_env_t {
103 be_chordal_env_t cenv;
105 const arch_register_class_t *cls;
106 double pre_spill_cost;
109 static be_options_t *main_opts;
111 static const lc_opt_enum_int_items_t lower_perm_items[] = {
112 { "copy", BE_CH_LOWER_PERM_COPY },
113 { "swap", BE_CH_LOWER_PERM_SWAP },
117 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
121 static const lc_opt_enum_int_items_t dump_items[] = {
122 { "none", BE_CH_DUMP_NONE },
123 { "spill", BE_CH_DUMP_SPILL },
124 { "live", BE_CH_DUMP_LIVE },
125 { "color", BE_CH_DUMP_COLOR },
126 { "copymin", BE_CH_DUMP_COPYMIN },
127 { "ssadestr", BE_CH_DUMP_SSADESTR },
128 { "tree", BE_CH_DUMP_TREE_INTV },
129 { "constr", BE_CH_DUMP_CONSTR },
130 { "lower", BE_CH_DUMP_LOWER },
131 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
132 { "appel", BE_CH_DUMP_APPEL },
133 { "all", BE_CH_DUMP_ALL },
137 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
138 { "off", BE_CH_VRFY_OFF },
139 { "warn", BE_CH_VRFY_WARN },
140 { "assert", BE_CH_VRFY_ASSERT },
144 static lc_opt_enum_int_var_t lower_perm_var = {
145 &options.lower_perm_opt, lower_perm_items
148 static lc_opt_enum_int_var_t dump_var = {
149 &options.dump_flags, dump_items
152 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
153 &options.vrfy_option, be_ch_vrfy_items
156 static const lc_opt_table_entry_t be_chordal_options[] = {
157 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
158 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
159 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
163 static void dump(unsigned mask, ir_graph *irg,
164 const arch_register_class_t *cls,
166 void (*dump_func)(ir_graph *, const char *))
168 if((options.dump_flags & mask) == mask) {
171 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
172 be_dump(irg, buf, dump_func);
175 be_dump(irg, suffix, dump_func);
180 * Checks for every reload if it's user can perform the load on itself.
182 static void memory_operand_walker(ir_node *irn, void *env) {
183 be_chordal_env_t *cenv = env;
184 const arch_env_t *aenv = cenv->birg->main_env->arch_env;
185 const ir_edge_t *edge, *ne;
189 if (! be_is_Reload(irn))
192 /* only use memory operands, if the reload is only used by 1 node */
193 if(get_irn_n_edges(irn) > 1)
196 spill = be_get_Reload_mem(irn);
197 block = get_nodes_block(irn);
199 foreach_out_edge_safe(irn, edge, ne) {
200 ir_node *src = get_edge_src_irn(edge);
201 int pos = get_edge_src_pos(edge);
203 assert(src && "outedges broken!");
205 if (get_nodes_block(src) == block && arch_possible_memory_operand(aenv, src, pos)) {
206 arch_perform_memory_operand(aenv, src, spill, pos);
210 /* kill the Reload */
211 if (get_irn_n_edges(irn) == 0) {
213 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
214 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
219 * Starts a walk for memory operands if supported by the backend.
221 static INLINE void check_for_memory_operands(be_chordal_env_t *chordal_env) {
222 irg_walk_graph(chordal_env->irg, NULL, memory_operand_walker, chordal_env);
226 * Sorry for doing stats again...
228 typedef struct _node_stat_t {
229 unsigned int n_phis; /**< Phis of the current register class. */
230 unsigned int n_mem_phis; /**< Memory Phis (Phis with spill operands). */
231 unsigned int n_copies; /**< Copies */
232 unsigned int n_perms; /**< Perms */
233 unsigned int n_spills; /**< Spill nodes */
234 unsigned int n_reloads; /**< Reloads */
237 struct node_stat_walker {
239 const arch_env_t *arch_env;
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 the node is a normal phi */
249 if (get_irn_mode(irn) == mode_M) {
250 env->stat->n_mem_phis++;
255 arch_irn_class_t classify = arch_irn_classify(aenv, irn);
257 if(classify & arch_irn_class_spill)
258 ++env->stat->n_spills;
259 if(classify & arch_irn_class_reload)
260 ++env->stat->n_reloads;
261 if(classify & arch_irn_class_copy)
262 ++env->stat->n_copies;
263 if(classify & arch_irn_class_perm)
264 ++env->stat->n_perms;
268 static void node_stats(be_irg_t *birg, node_stat_t *stat)
270 struct node_stat_walker env;
272 memset(stat, 0, sizeof(*stat));
273 env.arch_env = birg->main_env->arch_env;
275 irg_walk_graph(birg->irg, NULL, node_stat_walker, &env);
278 static void insn_count_walker(ir_node *irn, void *data)
280 unsigned long *cnt = data;
282 switch(get_irn_opcode(irn)) {
293 static unsigned long count_insns(ir_graph *irg)
295 unsigned long cnt = 0;
296 irg_walk_graph(irg, insn_count_walker, NULL, &cnt);
300 static void block_count_walker(ir_node *node, void *data)
302 unsigned long *cnt = data;
303 if (node == get_irg_end_block(current_ir_graph))
308 static unsigned long count_blocks(ir_graph *irg)
310 unsigned long cnt = 0;
311 irg_block_walk_graph(irg, block_count_walker, NULL, &cnt);
315 static node_stat_t last_node_stat;
318 * Perform things which need to be done per register class before spilling.
320 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
322 be_chordal_env_t *chordal_env = &pse->cenv;
323 be_irg_t *birg = pse->birg;
324 ir_graph *irg = be_get_birg_irg(birg);
325 const be_main_env_t *main_env = birg->main_env;
328 chordal_env->cls = cls;
329 chordal_env->border_heads = pmap_create();
330 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
332 be_assure_liveness(birg);
333 be_liveness_assure_chk(be_get_birg_liveness(birg));
335 stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq));
337 /* put all ignore registers into the ignore register set. */
338 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
340 BE_TIMER_PUSH(t_ra_constr);
341 be_pre_spill_prepare_constr(chordal_env);
342 BE_TIMER_POP(t_ra_constr);
344 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
348 * Perform things which need to be done per register class after spilling.
350 static void post_spill(post_spill_env_t *pse, int iteration) {
351 be_chordal_env_t *chordal_env = &pse->cenv;
352 be_irg_t *birg = pse->birg;
353 ir_graph *irg = birg->irg;
354 const be_main_env_t *main_env = birg->main_env;
355 int colors_n = arch_register_class_n_regs(chordal_env->cls);
356 int allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
358 /* some special classes contain only ignore regs, no work to be done */
359 if (allocatable_regs > 0) {
360 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost);
363 If we have a backend provided spiller, post spill is
364 called in a loop after spilling for each register class.
365 But we only need to fix stack nodes once in this case.
367 BE_TIMER_PUSH(t_ra_spill);
368 check_for_memory_operands(chordal_env);
369 if (iteration == 0) {
370 be_abi_fix_stack_nodes(birg->abi);
372 BE_TIMER_POP(t_ra_spill);
374 BE_TIMER_PUSH(t_verify);
376 /* verify schedule and register pressure */
377 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
378 be_verify_schedule(birg);
379 be_verify_register_pressure(birg, pse->cls, irg);
380 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
381 assert(be_verify_schedule(birg) && "Schedule verification failed");
382 assert(be_verify_register_pressure(birg, pse->cls, irg)
383 && "Register pressure verification failed");
385 BE_TIMER_POP(t_verify);
387 /* Color the graph. */
388 BE_TIMER_PUSH(t_ra_color);
389 be_ra_chordal_color(chordal_env);
390 BE_TIMER_POP(t_ra_color);
392 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
394 /* Create the ifg with the selected flavor */
395 BE_TIMER_PUSH(t_ra_ifg);
396 chordal_env->ifg = be_create_ifg(chordal_env);
397 BE_TIMER_POP(t_ra_ifg);
401 node_stat_t node_stat;
403 be_ifg_stat(birg, chordal_env->ifg, &stat);
404 stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
405 stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
406 stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
408 node_stats(birg, &node_stat);
409 stat_ev_dbl("bechordal_perms_before_coal",
410 node_stat.n_perms - last_node_stat.n_perms);
411 stat_ev_dbl("bechordal_copies_before_coal",
412 node_stat.n_copies - last_node_stat.n_copies);
415 /* copy minimization */
416 BE_TIMER_PUSH(t_ra_copymin);
417 co_driver(chordal_env);
418 BE_TIMER_POP(t_ra_copymin);
420 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
423 /* ssa destruction */
424 BE_TIMER_PUSH(t_ra_ssa);
425 be_ssa_destruction(chordal_env);
426 BE_TIMER_POP(t_ra_ssa);
428 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
430 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
431 BE_TIMER_PUSH(t_verify);
432 be_ssa_destruction_check(chordal_env);
433 BE_TIMER_POP(t_verify);
436 /* the ifg exists only if there are allocatable regs */
437 be_ifg_free(chordal_env->ifg);
440 /* free some always allocated data structures */
441 pmap_destroy(chordal_env->border_heads);
442 bitset_free(chordal_env->ignore_colors);
446 * Performs chordal register allocation for each register class on given irg.
448 * @param birg Backend irg object
449 * @return Structure containing timer for the single phases or NULL if no timing requested.
451 static void be_ra_chordal_main(be_irg_t *birg)
453 const be_main_env_t *main_env = birg->main_env;
454 const arch_env_t *arch_env = main_env->arch_env;
455 ir_graph *irg = birg->irg;
457 be_chordal_env_t chordal_env;
460 main_opts = main_env->options;
462 BE_TIMER_PUSH(t_ra_other);
464 BE_TIMER_PUSH(t_ra_prolog);
466 be_assure_liveness(birg);
468 chordal_env.obst = &obst;
469 chordal_env.opts = &options;
470 chordal_env.irg = irg;
471 chordal_env.birg = birg;
472 chordal_env.border_heads = NULL;
473 chordal_env.ifg = NULL;
474 chordal_env.ignore_colors = NULL;
478 BE_TIMER_POP(t_ra_prolog);
481 be_stat_ev("bechordal_insns_before", count_insns(irg));
482 be_stat_ev("bechordal_blocks_before", count_blocks(irg));
483 node_stats(birg, &last_node_stat);
486 if (! arch_code_generator_has_spiller(birg->cg)) {
487 /* use one of the generic spiller */
489 /* Perform the following for each register class. */
490 for (j = 0, m = arch_env_get_n_reg_class(arch_env); j < m; ++j) {
491 post_spill_env_t pse;
492 const arch_register_class_t *cls
493 = arch_env_get_reg_class(arch_env, j);
495 if(arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
499 stat_ev_ctx_push_str("bechordal_cls", cls->name);
501 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
503 pre_spill(&pse, cls);
505 BE_TIMER_PUSH(t_ra_spill);
506 be_do_spill(birg, cls);
507 BE_TIMER_POP(t_ra_spill);
509 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill",
510 dump_ir_block_graph_sched);
515 node_stat_t node_stat;
517 node_stats(birg, &node_stat);
518 stat_ev_dbl("bechordal_phis",
519 node_stat.n_phis - last_node_stat.n_phis);
520 stat_ev_dbl("bechordal_mem_phis",
521 node_stat.n_mem_phis - last_node_stat.n_mem_phis);
522 stat_ev_dbl("bechordal_reloads",
523 node_stat.n_reloads - last_node_stat.n_reloads);
524 stat_ev_dbl("bechordal_spills",
525 node_stat.n_spills - last_node_stat.n_spills);
526 stat_ev_dbl("bechordal_perms_after_coal",
527 node_stat.n_perms - last_node_stat.n_perms);
528 stat_ev_dbl("bechordal_copies_after_coal",
529 node_stat.n_copies - last_node_stat.n_copies);
531 last_node_stat = node_stat;
532 stat_ev_ctx_pop("bechordal_cls");
536 post_spill_env_t *pse;
538 /* the backend has its own spiller */
539 m = arch_env_get_n_reg_class(arch_env);
541 pse = alloca(m * sizeof(pse[0]));
543 for (j = 0; j < m; ++j) {
544 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
546 pre_spill(&pse[j], pse[j].cls);
549 BE_TIMER_PUSH(t_ra_spill);
550 arch_code_generator_spill(birg->cg, birg);
551 BE_TIMER_POP(t_ra_spill);
552 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
554 for (j = 0; j < m; ++j) {
555 post_spill(&pse[j], j);
559 BE_TIMER_PUSH(t_verify);
560 be_verify_register_allocation(birg);
561 BE_TIMER_POP(t_verify);
563 BE_TIMER_PUSH(t_ra_epilog);
564 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
565 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
567 obstack_free(&obst, NULL);
568 be_liveness_invalidate(be_get_birg_liveness(birg));
569 BE_TIMER_POP(t_ra_epilog);
571 BE_TIMER_POP(t_ra_other);
574 be_stat_ev("bechordal_insns_after", count_insns(irg));
578 static be_ra_t be_ra_chordal_allocator = {
582 void be_init_chordal_main(void)
584 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
585 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
586 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
588 lc_opt_add_table(chordal_grp, be_chordal_options);
590 be_register_allocator("chordal", &be_ra_chordal_allocator);
593 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);