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"
58 #include "iredges_t.h"
60 #include "bechordal_t.h"
62 #include "bejavacoal.h"
65 #include "besched_t.h"
69 #include "beifg_impl.h"
71 #include "bestatevent.h"
78 #include "bespillslots.h"
79 #include "bespilloptions.h"
83 #include "bespillremat.h"
86 #include "bejavacoal.h"
87 #include "becopystat.h"
88 #include "becopyopt.h"
89 #include "bessadestr.h"
93 static be_ra_chordal_opts_t options = {
95 BE_CH_LOWER_PERM_SWAP,
101 typedef struct _post_spill_env_t {
102 be_chordal_env_t cenv;
104 const arch_register_class_t *cls;
105 double pre_spill_cost;
108 static be_options_t *main_opts;
110 static const lc_opt_enum_int_items_t lower_perm_items[] = {
111 { "copy", BE_CH_LOWER_PERM_COPY },
112 { "swap", BE_CH_LOWER_PERM_SWAP },
116 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
120 static const lc_opt_enum_int_items_t dump_items[] = {
121 { "none", BE_CH_DUMP_NONE },
122 { "spill", BE_CH_DUMP_SPILL },
123 { "live", BE_CH_DUMP_LIVE },
124 { "color", BE_CH_DUMP_COLOR },
125 { "copymin", BE_CH_DUMP_COPYMIN },
126 { "ssadestr", BE_CH_DUMP_SSADESTR },
127 { "tree", BE_CH_DUMP_TREE_INTV },
128 { "constr", BE_CH_DUMP_CONSTR },
129 { "lower", BE_CH_DUMP_LOWER },
130 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
131 { "appel", BE_CH_DUMP_APPEL },
132 { "all", BE_CH_DUMP_ALL },
136 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
137 { "off", BE_CH_VRFY_OFF },
138 { "warn", BE_CH_VRFY_WARN },
139 { "assert", BE_CH_VRFY_ASSERT },
143 static lc_opt_enum_int_var_t lower_perm_var = {
144 &options.lower_perm_opt, lower_perm_items
147 static lc_opt_enum_int_var_t dump_var = {
148 &options.dump_flags, dump_items
151 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
152 &options.vrfy_option, be_ch_vrfy_items
155 static const lc_opt_table_entry_t be_chordal_options[] = {
156 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
157 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
158 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
162 static void dump(unsigned mask, ir_graph *irg,
163 const arch_register_class_t *cls,
165 void (*dump_func)(ir_graph *, const char *))
167 if((options.dump_flags & mask) == mask) {
170 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
171 be_dump(irg, buf, dump_func);
174 be_dump(irg, suffix, dump_func);
179 * Checks for every reload if its user can perform the load on itself.
181 static void memory_operand_walker(ir_node *irn, void *env)
183 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(src, pos)) {
206 arch_perform_memory_operand(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(ir_graph *irg)
223 irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
227 static be_node_stats_t last_node_stats;
230 * Perform things which need to be done per register class before spilling.
232 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
234 be_chordal_env_t *chordal_env = &pse->cenv;
235 be_irg_t *birg = pse->birg;
236 ir_graph *irg = be_get_birg_irg(birg);
237 const be_main_env_t *main_env = birg->main_env;
240 chordal_env->cls = cls;
241 chordal_env->border_heads = pmap_create();
242 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
244 be_assure_liveness(birg);
245 be_liveness_assure_chk(be_get_birg_liveness(birg));
247 stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq));
249 /* put all ignore registers into the ignore register set. */
250 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
252 BE_TIMER_PUSH(t_ra_constr);
253 be_pre_spill_prepare_constr(chordal_env);
254 BE_TIMER_POP(t_ra_constr);
256 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
260 * Perform things which need to be done per register class after spilling.
262 static void post_spill(post_spill_env_t *pse, int iteration) {
263 be_chordal_env_t *chordal_env = &pse->cenv;
264 be_irg_t *birg = pse->birg;
265 ir_graph *irg = birg->irg;
266 const be_main_env_t *main_env = birg->main_env;
267 int colors_n = arch_register_class_n_regs(chordal_env->cls);
268 int allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
270 /* some special classes contain only ignore regs, no work to be done */
271 if (allocatable_regs > 0) {
272 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost);
275 If we have a backend provided spiller, post spill is
276 called in a loop after spilling for each register class.
277 But we only need to fix stack nodes once in this case.
279 BE_TIMER_PUSH(t_ra_spill_apply);
280 check_for_memory_operands(irg);
281 if (iteration == 0) {
282 be_abi_fix_stack_nodes(birg->abi);
284 BE_TIMER_POP(t_ra_spill_apply);
286 BE_TIMER_PUSH(t_verify);
288 /* verify schedule and register pressure */
289 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
290 be_verify_schedule(birg);
291 be_verify_register_pressure(birg, pse->cls, irg);
292 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
293 assert(be_verify_schedule(birg) && "Schedule verification failed");
294 assert(be_verify_register_pressure(birg, pse->cls, irg)
295 && "Register pressure verification failed");
297 BE_TIMER_POP(t_verify);
299 /* Color the graph. */
300 BE_TIMER_PUSH(t_ra_color);
301 be_ra_chordal_color(chordal_env);
302 BE_TIMER_POP(t_ra_color);
304 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
306 /* Create the ifg with the selected flavor */
307 BE_TIMER_PUSH(t_ra_ifg);
308 chordal_env->ifg = be_create_ifg(chordal_env);
309 BE_TIMER_POP(t_ra_ifg);
313 be_node_stats_t node_stats;
315 be_ifg_stat(birg, chordal_env->ifg, &stat);
316 stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
317 stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
318 stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
320 be_collect_node_stats(&node_stats, birg);
321 be_subtract_node_stats(&node_stats, &last_node_stats);
323 stat_ev_dbl("bechordal_perms_before_coal",
324 node_stats[BE_STAT_PERMS]);
325 stat_ev_dbl("bechordal_copies_before_coal",
326 node_stats[BE_STAT_COPIES]);
329 /* copy minimization */
330 BE_TIMER_PUSH(t_ra_copymin);
331 co_driver(chordal_env);
332 BE_TIMER_POP(t_ra_copymin);
334 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
337 /* ssa destruction */
338 BE_TIMER_PUSH(t_ra_ssa);
339 be_ssa_destruction(chordal_env);
340 BE_TIMER_POP(t_ra_ssa);
342 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
344 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
345 BE_TIMER_PUSH(t_verify);
346 be_ssa_destruction_check(chordal_env);
347 BE_TIMER_POP(t_verify);
350 /* the ifg exists only if there are allocatable regs */
351 be_ifg_free(chordal_env->ifg);
354 /* free some always allocated data structures */
355 pmap_destroy(chordal_env->border_heads);
356 bitset_free(chordal_env->ignore_colors);
360 * Performs chordal register allocation for each register class on given irg.
362 * @param birg Backend irg object
363 * @return Structure containing timer for the single phases or NULL if no timing requested.
365 static void be_ra_chordal_main(be_irg_t *birg)
367 const be_main_env_t *main_env = birg->main_env;
368 const arch_env_t *arch_env = main_env->arch_env;
369 ir_graph *irg = birg->irg;
371 be_chordal_env_t chordal_env;
374 main_opts = main_env->options;
376 BE_TIMER_PUSH(t_ra_other);
378 BE_TIMER_PUSH(t_ra_prolog);
380 be_assure_liveness(birg);
382 chordal_env.obst = &obst;
383 chordal_env.opts = &options;
384 chordal_env.irg = irg;
385 chordal_env.birg = birg;
386 chordal_env.border_heads = NULL;
387 chordal_env.ifg = NULL;
388 chordal_env.ignore_colors = NULL;
392 BE_TIMER_POP(t_ra_prolog);
395 be_collect_node_stats(&last_node_stats, birg);
398 if (! arch_code_generator_has_spiller(birg->cg)) {
399 /* use one of the generic spiller */
401 /* Perform the following for each register class. */
402 for (j = 0, m = arch_env_get_n_reg_class(arch_env); j < m; ++j) {
403 post_spill_env_t pse;
404 const arch_register_class_t *cls
405 = arch_env_get_reg_class(arch_env, j);
407 if(arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
411 stat_ev_ctx_push_str("bechordal_cls", cls->name);
414 be_do_stat_reg_pressure(birg, cls);
417 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
419 pre_spill(&pse, cls);
421 BE_TIMER_PUSH(t_ra_spill);
422 be_do_spill(birg, cls);
423 BE_TIMER_POP(t_ra_spill);
425 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill",
426 dump_ir_block_graph_sched);
431 be_node_stats_t node_stats;
433 be_collect_node_stats(&node_stats, birg);
434 be_subtract_node_stats(&node_stats, &last_node_stats);
435 be_emit_node_stats(&node_stats, "bechordal_");
437 be_copy_node_stats(&last_node_stats, &node_stats);
438 stat_ev_ctx_pop("bechordal_cls");
442 post_spill_env_t *pse;
444 /* the backend has its own spiller */
445 m = arch_env_get_n_reg_class(arch_env);
447 pse = alloca(m * sizeof(pse[0]));
449 for (j = 0; j < m; ++j) {
450 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
452 pre_spill(&pse[j], pse[j].cls);
455 BE_TIMER_PUSH(t_ra_spill);
456 arch_code_generator_spill(birg->cg, birg);
457 BE_TIMER_POP(t_ra_spill);
458 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
460 for (j = 0; j < m; ++j) {
461 post_spill(&pse[j], j);
465 BE_TIMER_PUSH(t_verify);
466 be_verify_register_allocation(birg);
467 BE_TIMER_POP(t_verify);
469 BE_TIMER_PUSH(t_ra_epilog);
470 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
471 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
473 obstack_free(&obst, NULL);
474 be_liveness_invalidate(be_get_birg_liveness(birg));
475 BE_TIMER_POP(t_ra_epilog);
477 BE_TIMER_POP(t_ra_other);
480 static be_ra_t be_ra_chordal_allocator = {
484 void be_init_chordal_main(void)
486 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
487 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
488 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
490 lc_opt_add_table(chordal_grp, be_chordal_options);
492 be_register_allocator("chordal", &be_ra_chordal_allocator);
495 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);