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 "lc_opts_enum.h"
43 #include "irgraph_t.h"
44 #include "irprintf_t.h"
55 #include "iredges_t.h"
57 #include "bechordal_t.h"
61 #include "besched_t.h"
65 #include "beifg_impl.h"
67 #include "bestatevent.h"
74 #include "bespillslots.h"
75 #include "bespilloptions.h"
78 #include "becopystat.h"
79 #include "becopyopt.h"
80 #include "bessadestr.h"
84 static be_ra_chordal_opts_t options = {
86 BE_CH_LOWER_PERM_SWAP,
92 typedef struct _post_spill_env_t {
93 be_chordal_env_t cenv;
95 const arch_register_class_t *cls;
96 double pre_spill_cost;
99 static be_options_t *main_opts;
101 static const lc_opt_enum_int_items_t lower_perm_items[] = {
102 { "copy", BE_CH_LOWER_PERM_COPY },
103 { "swap", BE_CH_LOWER_PERM_SWAP },
107 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
111 static const lc_opt_enum_int_items_t dump_items[] = {
112 { "none", BE_CH_DUMP_NONE },
113 { "spill", BE_CH_DUMP_SPILL },
114 { "live", BE_CH_DUMP_LIVE },
115 { "color", BE_CH_DUMP_COLOR },
116 { "copymin", BE_CH_DUMP_COPYMIN },
117 { "ssadestr", BE_CH_DUMP_SSADESTR },
118 { "tree", BE_CH_DUMP_TREE_INTV },
119 { "constr", BE_CH_DUMP_CONSTR },
120 { "lower", BE_CH_DUMP_LOWER },
121 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
122 { "appel", BE_CH_DUMP_APPEL },
123 { "all", BE_CH_DUMP_ALL },
127 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
128 { "off", BE_CH_VRFY_OFF },
129 { "warn", BE_CH_VRFY_WARN },
130 { "assert", BE_CH_VRFY_ASSERT },
134 static lc_opt_enum_int_var_t lower_perm_var = {
135 &options.lower_perm_opt, lower_perm_items
138 static lc_opt_enum_int_var_t dump_var = {
139 &options.dump_flags, dump_items
142 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
143 &options.vrfy_option, be_ch_vrfy_items
146 static const lc_opt_table_entry_t be_chordal_options[] = {
147 LC_OPT_ENT_ENUM_PTR ("perm", "perm lowering options", &lower_perm_var),
148 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
149 LC_OPT_ENT_ENUM_PTR ("vrfy", "verify options", &be_ch_vrfy_var),
153 static void dump(unsigned mask, ir_graph *irg,
154 const arch_register_class_t *cls,
156 void (*dump_func)(ir_graph *, const char *))
158 if((options.dump_flags & mask) == mask) {
161 snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
162 be_dump(irg, buf, dump_func);
165 be_dump(irg, suffix, dump_func);
170 * Checks for every reload if its user can perform the load on itself.
172 static void memory_operand_walker(ir_node *irn, void *env)
174 const ir_edge_t *edge, *ne;
180 if (! be_is_Reload(irn))
183 /* only use memory operands, if the reload is only used by 1 node */
184 if(get_irn_n_edges(irn) > 1)
187 spill = be_get_Reload_mem(irn);
188 block = get_nodes_block(irn);
190 foreach_out_edge_safe(irn, edge, ne) {
191 ir_node *src = get_edge_src_irn(edge);
192 int pos = get_edge_src_pos(edge);
194 assert(src && "outedges broken!");
196 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
197 arch_perform_memory_operand(src, spill, pos);
201 /* kill the Reload */
202 if (get_irn_n_edges(irn) == 0) {
204 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
205 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
210 * Starts a walk for memory operands if supported by the backend.
212 static INLINE void check_for_memory_operands(ir_graph *irg)
214 irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
218 static be_node_stats_t last_node_stats;
221 * Perform things which need to be done per register class before spilling.
223 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
225 be_chordal_env_t *chordal_env = &pse->cenv;
226 be_irg_t *birg = pse->birg;
227 ir_graph *irg = be_get_birg_irg(birg);
228 const be_main_env_t *main_env = birg->main_env;
231 chordal_env->cls = cls;
232 chordal_env->border_heads = pmap_create();
233 chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
235 be_assure_liveness(birg);
236 be_liveness_assure_chk(be_get_birg_liveness(birg));
238 stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq));
240 /* put all ignore registers into the ignore register set. */
241 be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
243 BE_TIMER_PUSH(t_ra_constr);
244 be_pre_spill_prepare_constr(chordal_env);
245 BE_TIMER_POP(t_ra_constr);
247 dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
251 * Perform things which need to be done per register class after spilling.
253 static void post_spill(post_spill_env_t *pse, int iteration) {
254 be_chordal_env_t *chordal_env = &pse->cenv;
255 be_irg_t *birg = pse->birg;
256 ir_graph *irg = birg->irg;
257 const be_main_env_t *main_env = birg->main_env;
258 int colors_n = arch_register_class_n_regs(chordal_env->cls);
259 int allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
261 /* some special classes contain only ignore regs, no work to be done */
262 if (allocatable_regs > 0) {
263 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq) - pse->pre_spill_cost);
266 If we have a backend provided spiller, post spill is
267 called in a loop after spilling for each register class.
268 But we only need to fix stack nodes once in this case.
270 BE_TIMER_PUSH(t_ra_spill_apply);
271 check_for_memory_operands(irg);
272 if (iteration == 0) {
273 be_abi_fix_stack_nodes(birg->abi);
275 BE_TIMER_POP(t_ra_spill_apply);
277 BE_TIMER_PUSH(t_verify);
279 /* verify schedule and register pressure */
280 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
281 be_verify_schedule(birg);
282 be_verify_register_pressure(birg, pse->cls, irg);
283 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
284 assert(be_verify_schedule(birg) && "Schedule verification failed");
285 assert(be_verify_register_pressure(birg, pse->cls, irg)
286 && "Register pressure verification failed");
288 BE_TIMER_POP(t_verify);
290 /* Color the graph. */
291 BE_TIMER_PUSH(t_ra_color);
292 be_ra_chordal_color(chordal_env);
293 BE_TIMER_POP(t_ra_color);
295 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
297 /* Create the ifg with the selected flavor */
298 BE_TIMER_PUSH(t_ra_ifg);
299 chordal_env->ifg = be_create_ifg(chordal_env);
300 BE_TIMER_POP(t_ra_ifg);
304 be_node_stats_t node_stats;
306 be_ifg_stat(birg, chordal_env->ifg, &stat);
307 stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
308 stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
309 stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
311 be_collect_node_stats(&node_stats, birg);
312 be_subtract_node_stats(&node_stats, &last_node_stats);
314 stat_ev_dbl("bechordal_perms_before_coal",
315 node_stats[BE_STAT_PERMS]);
316 stat_ev_dbl("bechordal_copies_before_coal",
317 node_stats[BE_STAT_COPIES]);
320 /* copy minimization */
321 BE_TIMER_PUSH(t_ra_copymin);
322 co_driver(chordal_env);
323 BE_TIMER_POP(t_ra_copymin);
325 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
328 /* ssa destruction */
329 BE_TIMER_PUSH(t_ra_ssa);
330 be_ssa_destruction(chordal_env);
331 BE_TIMER_POP(t_ra_ssa);
333 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
335 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
336 BE_TIMER_PUSH(t_verify);
337 be_ssa_destruction_check(chordal_env);
338 BE_TIMER_POP(t_verify);
341 /* the ifg exists only if there are allocatable regs */
342 be_ifg_free(chordal_env->ifg);
345 /* free some always allocated data structures */
346 pmap_destroy(chordal_env->border_heads);
347 bitset_free(chordal_env->ignore_colors);
351 * Performs chordal register allocation for each register class on given irg.
353 * @param birg Backend irg object
354 * @return Structure containing timer for the single phases or NULL if no timing requested.
356 static void be_ra_chordal_main(be_irg_t *birg)
358 const be_main_env_t *main_env = birg->main_env;
359 const arch_env_t *arch_env = main_env->arch_env;
360 ir_graph *irg = birg->irg;
362 be_chordal_env_t chordal_env;
365 main_opts = main_env->options;
367 BE_TIMER_PUSH(t_ra_other);
369 BE_TIMER_PUSH(t_ra_prolog);
371 be_assure_liveness(birg);
373 chordal_env.obst = &obst;
374 chordal_env.opts = &options;
375 chordal_env.irg = irg;
376 chordal_env.birg = birg;
377 chordal_env.border_heads = NULL;
378 chordal_env.ifg = NULL;
379 chordal_env.ignore_colors = NULL;
383 BE_TIMER_POP(t_ra_prolog);
386 be_collect_node_stats(&last_node_stats, birg);
389 if (! arch_code_generator_has_spiller(birg->cg)) {
390 /* use one of the generic spiller */
392 /* Perform the following for each register class. */
393 for (j = 0, m = arch_env_get_n_reg_class(arch_env); j < m; ++j) {
394 post_spill_env_t pse;
395 const arch_register_class_t *cls
396 = arch_env_get_reg_class(arch_env, j);
398 if(arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
402 stat_ev_ctx_push_str("bechordal_cls", cls->name);
405 be_do_stat_reg_pressure(birg, cls);
408 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
410 pre_spill(&pse, cls);
412 BE_TIMER_PUSH(t_ra_spill);
413 be_do_spill(birg, cls);
414 BE_TIMER_POP(t_ra_spill);
416 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill",
417 dump_ir_block_graph_sched);
422 be_node_stats_t node_stats;
424 be_collect_node_stats(&node_stats, birg);
425 be_subtract_node_stats(&node_stats, &last_node_stats);
426 be_emit_node_stats(&node_stats, "bechordal_");
428 be_copy_node_stats(&last_node_stats, &node_stats);
429 stat_ev_ctx_pop("bechordal_cls");
433 post_spill_env_t *pse;
435 /* the backend has its own spiller */
436 m = arch_env_get_n_reg_class(arch_env);
438 pse = alloca(m * sizeof(pse[0]));
440 for (j = 0; j < m; ++j) {
441 memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
443 pre_spill(&pse[j], pse[j].cls);
446 BE_TIMER_PUSH(t_ra_spill);
447 arch_code_generator_spill(birg->cg, birg);
448 BE_TIMER_POP(t_ra_spill);
449 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
451 for (j = 0; j < m; ++j) {
452 post_spill(&pse[j], j);
456 BE_TIMER_PUSH(t_verify);
457 be_verify_register_allocation(birg);
458 BE_TIMER_POP(t_verify);
460 BE_TIMER_PUSH(t_ra_epilog);
461 lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
462 dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
464 obstack_free(&obst, NULL);
465 be_liveness_invalidate(be_get_birg_liveness(birg));
466 BE_TIMER_POP(t_ra_epilog);
468 BE_TIMER_POP(t_ra_other);
471 static be_ra_t be_ra_chordal_allocator = {
475 void be_init_chordal_main(void)
477 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
478 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
479 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
481 lc_opt_add_table(chordal_grp, be_chordal_options);
483 be_register_allocator("chordal", &be_ra_chordal_allocator);
486 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);