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
37 #include "lc_opts_enum.h"
41 #include "irgraph_t.h"
42 #include "irprintf_t.h"
53 #include "iredges_t.h"
56 #include "bechordal_t.h"
73 #include "bespillslots.h"
77 #include "becopystat.h"
78 #include "becopyopt.h"
79 #include "bessadestr.h"
83 #include "bepbqpcoloring.h"
85 static be_ra_chordal_opts_t options = {
87 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 const lc_opt_enum_int_items_t lower_perm_items[] = {
100 { "copy", BE_CH_LOWER_PERM_COPY },
101 { "swap", BE_CH_LOWER_PERM_SWAP },
105 static const lc_opt_enum_mask_items_t dump_items[] = {
106 { "none", BE_CH_DUMP_NONE },
107 { "spill", BE_CH_DUMP_SPILL },
108 { "live", BE_CH_DUMP_LIVE },
109 { "color", BE_CH_DUMP_COLOR },
110 { "copymin", BE_CH_DUMP_COPYMIN },
111 { "ssadestr", BE_CH_DUMP_SSADESTR },
112 { "tree", BE_CH_DUMP_TREE_INTV },
113 { "split", BE_CH_DUMP_SPLIT },
114 { "constr", BE_CH_DUMP_CONSTR },
115 { "lower", BE_CH_DUMP_LOWER },
116 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
117 { "appel", BE_CH_DUMP_APPEL },
118 { "all", BE_CH_DUMP_ALL },
122 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
123 { "off", BE_CH_VRFY_OFF },
124 { "warn", BE_CH_VRFY_WARN },
125 { "assert", BE_CH_VRFY_ASSERT },
129 static lc_opt_enum_int_var_t lower_perm_var = {
130 &options.lower_perm_opt, lower_perm_items
133 static lc_opt_enum_mask_var_t dump_var = {
134 &options.dump_flags, dump_items
137 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
138 &options.vrfy_option, be_ch_vrfy_items
141 static const lc_opt_table_entry_t be_chordal_options[] = {
142 LC_OPT_ENT_ENUM_INT ("perm", "perm lowering options", &lower_perm_var),
143 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
144 LC_OPT_ENT_ENUM_INT ("verify", "verify options", &be_ch_vrfy_var),
148 static be_module_list_entry_t *colorings = NULL;
149 static const be_ra_chordal_coloring_t *selected_coloring = NULL;
151 void be_register_chordal_coloring(const char *name, be_ra_chordal_coloring_t *coloring)
153 if (selected_coloring == NULL)
154 selected_coloring = coloring;
156 be_add_module_to_list(&colorings, name, coloring);
159 static void be_ra_chordal_coloring(be_chordal_env_t *env)
161 selected_coloring->allocate(env);
164 static void dump(unsigned mask, ir_graph *irg,
165 const arch_register_class_t *cls,
168 if ((options.dump_flags & mask) == mask) {
171 snprintf(buf, sizeof(buf), "%s-%s", cls->name, suffix);
172 dump_ir_graph(irg, buf);
174 dump_ir_graph(irg, suffix);
180 * Post-Walker: Checks for the given reload if has only one user that can perform the
181 * reload as part of its address mode.
182 * Fold the reload into the user it that is possible.
184 static void memory_operand_walker(ir_node *irn, void *env)
191 if (! be_is_Reload(irn))
194 /* only use memory operands, if the reload is only used by 1 node */
195 if (get_irn_n_edges(irn) > 1)
198 spill = be_get_Reload_mem(irn);
199 block = get_nodes_block(irn);
201 foreach_out_edge_safe(irn, edge) {
202 ir_node *src = get_edge_src_irn(edge);
203 int pos = get_edge_src_pos(edge);
205 assert(src && "outedges broken!");
207 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
208 arch_perform_memory_operand(src, spill, pos);
212 /* kill the Reload if it was folded */
213 if (get_irn_n_edges(irn) == 0) {
214 ir_graph *irg = get_irn_irg(irn);
215 ir_mode *frame_mode = get_irn_mode(get_irn_n(irn, n_be_Reload_frame));
217 set_irn_n(irn, n_be_Reload_mem, new_r_Bad(irg, mode_X));
218 set_irn_n(irn, n_be_Reload_frame, new_r_Bad(irg, frame_mode));
223 * Starts a walk for memory operands if supported by the backend.
225 void check_for_memory_operands(ir_graph *irg)
227 irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
231 static be_node_stats_t last_node_stats;
234 * Perform things which need to be done per register class before spilling.
236 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
238 be_chordal_env_t *chordal_env = &pse->cenv;
239 ir_graph *irg = pse->irg;
242 chordal_env->cls = cls;
243 chordal_env->border_heads = pmap_create();
244 chordal_env->allocatable_regs = bitset_malloc(chordal_env->cls->n_regs);
246 be_assure_live_chk(irg);
248 if (stat_ev_enabled) {
249 pse->pre_spill_cost = be_estimate_irg_costs(irg);
252 /* put all ignore registers into the ignore register set. */
253 be_put_allocatable_regs(irg, pse->cls, chordal_env->allocatable_regs);
255 be_timer_push(T_RA_CONSTR);
256 be_pre_spill_prepare_constr(irg, chordal_env->cls);
257 be_timer_pop(T_RA_CONSTR);
259 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "constr-pre");
263 * Perform things which need to be done per register class after spilling.
265 static void post_spill(post_spill_env_t *pse, int iteration)
267 be_chordal_env_t *chordal_env = &pse->cenv;
268 ir_graph *irg = pse->irg;
269 int allocatable_regs = be_get_n_allocatable_regs(irg, chordal_env->cls);
271 /* some special classes contain only ignore regs, no work to be done */
272 if (allocatable_regs > 0) {
273 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg) - pse->pre_spill_cost);
276 If we have a backend provided spiller, post spill is
277 called in a loop after spilling for each register class.
278 But we only need to fix stack nodes once in this case.
280 be_timer_push(T_RA_SPILL_APPLY);
281 check_for_memory_operands(irg);
282 if (iteration == 0) {
283 be_abi_fix_stack_nodes(irg);
285 be_timer_pop(T_RA_SPILL_APPLY);
288 /* verify schedule and register pressure */
289 be_timer_push(T_VERIFY);
290 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
291 be_verify_schedule(irg);
292 be_verify_register_pressure(irg, pse->cls);
293 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
294 assert(be_verify_schedule(irg) && "Schedule verification failed");
295 assert(be_verify_register_pressure(irg, pse->cls)
296 && "Register pressure verification failed");
298 be_timer_pop(T_VERIFY);
300 /* Color the graph. */
301 be_timer_push(T_RA_COLOR);
302 be_ra_chordal_coloring(chordal_env);
303 be_timer_pop(T_RA_COLOR);
305 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "color");
307 /* Create the ifg with the selected flavor */
308 be_timer_push(T_RA_IFG);
309 chordal_env->ifg = be_create_ifg(chordal_env);
310 be_timer_pop(T_RA_IFG);
312 if (stat_ev_enabled) {
314 be_node_stats_t node_stats;
316 be_ifg_stat(irg, chordal_env->ifg, &stat);
317 stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
318 stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
319 stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
321 be_collect_node_stats(&node_stats, irg);
322 be_subtract_node_stats(&node_stats, &last_node_stats);
324 stat_ev_dbl("bechordal_perms_before_coal",
325 node_stats[BE_STAT_PERMS]);
326 stat_ev_dbl("bechordal_copies_before_coal",
327 node_stats[BE_STAT_COPIES]);
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");
336 /* ssa destruction */
337 be_timer_push(T_RA_SSA);
338 be_ssa_destruction(chordal_env);
339 be_timer_pop(T_RA_SSA);
341 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "ssadestr");
343 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
344 be_timer_push(T_VERIFY);
345 be_ssa_destruction_check(chordal_env);
346 be_timer_pop(T_VERIFY);
349 /* the ifg exists only if there are allocatable regs */
350 be_ifg_free(chordal_env->ifg);
353 /* free some always allocated data structures */
354 pmap_destroy(chordal_env->border_heads);
355 bitset_free(chordal_env->allocatable_regs);
359 * Performs chordal register allocation for each register class on given irg.
361 * @param irg the graph
362 * @return Structure containing timer for the single phases or NULL if no
365 static void be_ra_chordal_main(ir_graph *irg)
367 const arch_env_t *arch_env = be_get_irg_arch_env(irg);
370 be_chordal_env_t chordal_env;
373 be_timer_push(T_RA_OTHER);
375 be_timer_push(T_RA_PROLOG);
377 chordal_env.obst = &obst;
378 chordal_env.opts = &options;
379 chordal_env.irg = irg;
380 chordal_env.border_heads = NULL;
381 chordal_env.ifg = NULL;
382 chordal_env.allocatable_regs = NULL;
386 be_timer_pop(T_RA_PROLOG);
388 if (stat_ev_enabled) {
389 be_collect_node_stats(&last_node_stats, irg);
392 /* use one of the generic spiller */
394 /* Perform the following for each register class. */
395 for (j = 0, m = arch_env->n_register_classes; j < m; ++j) {
396 post_spill_env_t pse;
397 const arch_register_class_t *cls = &arch_env->register_classes[j];
399 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
403 stat_ev_ctx_push_str("bechordal_cls", cls->name);
405 if (stat_ev_enabled) {
406 be_do_stat_reg_pressure(irg, cls);
409 pse.cenv = chordal_env;
411 pre_spill(&pse, cls);
413 be_timer_push(T_RA_SPILL);
414 be_do_spill(irg, cls);
415 be_timer_pop(T_RA_SPILL);
417 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "spill");
421 if (stat_ev_enabled) {
422 be_node_stats_t node_stats;
424 be_collect_node_stats(&node_stats, irg);
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 be_timer_push(T_VERIFY);
434 if (chordal_env.opts->vrfy_option == BE_CH_VRFY_WARN) {
435 be_verify_register_allocation(irg);
436 } else if (chordal_env.opts->vrfy_option == BE_CH_VRFY_ASSERT) {
437 assert(be_verify_register_allocation(irg)
438 && "Register allocation invalid");
440 be_timer_pop(T_VERIFY);
442 be_timer_push(T_RA_EPILOG);
443 lower_nodes_after_ra(irg, options.lower_perm_opt == BE_CH_LOWER_PERM_COPY);
444 dump(BE_CH_DUMP_LOWER, irg, NULL, "belower-after-ra");
446 obstack_free(&obst, NULL);
447 be_invalidate_live_sets(irg);
448 be_timer_pop(T_RA_EPILOG);
450 be_timer_pop(T_RA_OTHER);
453 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main)
454 void be_init_chordal_main(void)
456 static be_ra_t be_ra_chordal_allocator = {
460 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
461 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
462 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
464 be_register_allocator("chordal", &be_ra_chordal_allocator);
466 lc_opt_add_table(chordal_grp, be_chordal_options);
467 be_add_module_list_opt(chordal_grp, "coloring", "select coloring method", &colorings, (void**) &selected_coloring);