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"
56 #include "iredges_t.h"
59 #include "bechordal_t.h"
68 #include "bestatevent.h"
76 #include "bespillslots.h"
80 #include "becopystat.h"
81 #include "becopyopt.h"
82 #include "bessadestr.h"
86 #include "bepbqpcoloring.h"
88 static be_ra_chordal_opts_t options = {
90 BE_CH_LOWER_PERM_SWAP,
96 typedef struct post_spill_env_t {
97 be_chordal_env_t cenv;
99 const arch_register_class_t *cls;
100 double pre_spill_cost;
103 static const lc_opt_enum_int_items_t lower_perm_items[] = {
104 { "copy", BE_CH_LOWER_PERM_COPY },
105 { "swap", BE_CH_LOWER_PERM_SWAP },
109 static const lc_opt_enum_mask_items_t dump_items[] = {
110 { "none", BE_CH_DUMP_NONE },
111 { "spill", BE_CH_DUMP_SPILL },
112 { "live", BE_CH_DUMP_LIVE },
113 { "color", BE_CH_DUMP_COLOR },
114 { "copymin", BE_CH_DUMP_COPYMIN },
115 { "ssadestr", BE_CH_DUMP_SSADESTR },
116 { "tree", BE_CH_DUMP_TREE_INTV },
117 { "constr", BE_CH_DUMP_CONSTR },
118 { "lower", BE_CH_DUMP_LOWER },
119 { "spillslots", BE_CH_DUMP_SPILLSLOTS },
120 { "appel", BE_CH_DUMP_APPEL },
121 { "all", BE_CH_DUMP_ALL },
125 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
126 { "off", BE_CH_VRFY_OFF },
127 { "warn", BE_CH_VRFY_WARN },
128 { "assert", BE_CH_VRFY_ASSERT },
132 static lc_opt_enum_int_var_t lower_perm_var = {
133 &options.lower_perm_opt, lower_perm_items
136 static lc_opt_enum_mask_var_t dump_var = {
137 &options.dump_flags, dump_items
140 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
141 &options.vrfy_option, be_ch_vrfy_items
144 static const lc_opt_table_entry_t be_chordal_options[] = {
145 LC_OPT_ENT_ENUM_INT ("perm", "perm lowering options", &lower_perm_var),
146 LC_OPT_ENT_ENUM_MASK("dump", "select dump phases", &dump_var),
147 LC_OPT_ENT_ENUM_INT ("verify", "verify options", &be_ch_vrfy_var),
151 static be_module_list_entry_t *colorings = NULL;
152 static const be_ra_chordal_coloring_t *selected_coloring = NULL;
154 void be_register_chordal_coloring(const char *name, be_ra_chordal_coloring_t *coloring)
156 if (selected_coloring == NULL)
157 selected_coloring = coloring;
159 be_add_module_to_list(&colorings, name, coloring);
162 static void be_ra_chordal_coloring(be_chordal_env_t *env)
164 selected_coloring->allocate(env);
167 static void dump(unsigned mask, ir_graph *irg,
168 const arch_register_class_t *cls,
171 if ((options.dump_flags & mask) == mask) {
174 snprintf(buf, sizeof(buf), "%s-%s", cls->name, suffix);
175 dump_ir_graph(irg, buf);
177 dump_ir_graph(irg, suffix);
183 * Post-Walker: Checks for the given reload if has only one user that can perform the
184 * reload as part of its address mode.
185 * Fold the reload into the user it that is possible.
187 static void memory_operand_walker(ir_node *irn, void *env)
189 const ir_edge_t *edge, *ne;
195 if (! be_is_Reload(irn))
198 /* only use memory operands, if the reload is only used by 1 node */
199 if (get_irn_n_edges(irn) > 1)
202 spill = be_get_Reload_mem(irn);
203 block = get_nodes_block(irn);
205 foreach_out_edge_safe(irn, edge, ne) {
206 ir_node *src = get_edge_src_irn(edge);
207 int pos = get_edge_src_pos(edge);
209 assert(src && "outedges broken!");
211 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
212 arch_perform_memory_operand(src, spill, pos);
216 /* kill the Reload if it was folded */
217 if (get_irn_n_edges(irn) == 0) {
218 ir_graph *irg = get_irn_irg(irn);
219 ir_mode *frame_mode = get_irn_mode(get_irn_n(irn, n_be_Reload_frame));
221 set_irn_n(irn, n_be_Reload_mem, new_r_Bad(irg, mode_X));
222 set_irn_n(irn, n_be_Reload_frame, new_r_Bad(irg, frame_mode));
227 * Starts a walk for memory operands if supported by the backend.
229 void check_for_memory_operands(ir_graph *irg)
231 irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
235 static be_node_stats_t last_node_stats;
238 * Perform things which need to be done per register class before spilling.
240 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
242 be_chordal_env_t *chordal_env = &pse->cenv;
243 ir_graph *irg = pse->irg;
244 ir_exec_freq *exec_freq = be_get_irg_exec_freq(irg);
247 chordal_env->cls = cls;
248 chordal_env->border_heads = pmap_create();
249 chordal_env->allocatable_regs = bitset_malloc(chordal_env->cls->n_regs);
251 be_assure_liveness(irg);
252 be_liveness_assure_chk(be_get_irg_liveness(irg));
254 if (stat_ev_enabled) {
255 pse->pre_spill_cost = be_estimate_irg_costs(irg, exec_freq);
258 /* put all ignore registers into the ignore register set. */
259 be_put_allocatable_regs(irg, pse->cls, chordal_env->allocatable_regs);
261 be_timer_push(T_RA_CONSTR);
262 be_pre_spill_prepare_constr(irg, chordal_env->cls);
263 be_timer_pop(T_RA_CONSTR);
265 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "constr-pre");
269 * Perform things which need to be done per register class after spilling.
271 static void post_spill(post_spill_env_t *pse, int iteration)
273 be_chordal_env_t *chordal_env = &pse->cenv;
274 ir_graph *irg = pse->irg;
275 ir_exec_freq *exec_freq = be_get_irg_exec_freq(irg);
276 int allocatable_regs = be_get_n_allocatable_regs(irg, chordal_env->cls);
278 /* some special classes contain only ignore regs, no work to be done */
279 if (allocatable_regs > 0) {
280 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, exec_freq) - pse->pre_spill_cost);
283 If we have a backend provided spiller, post spill is
284 called in a loop after spilling for each register class.
285 But we only need to fix stack nodes once in this case.
287 be_timer_push(T_RA_SPILL_APPLY);
288 check_for_memory_operands(irg);
289 if (iteration == 0) {
290 be_abi_fix_stack_nodes(irg);
292 be_timer_pop(T_RA_SPILL_APPLY);
295 /* verify schedule and register pressure */
296 be_timer_push(T_VERIFY);
297 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
298 be_verify_schedule(irg);
299 be_verify_register_pressure(irg, pse->cls);
300 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
301 assert(be_verify_schedule(irg) && "Schedule verification failed");
302 assert(be_verify_register_pressure(irg, pse->cls)
303 && "Register pressure verification failed");
305 be_timer_pop(T_VERIFY);
307 /* Color the graph. */
308 be_timer_push(T_RA_COLOR);
309 be_ra_chordal_coloring(chordal_env);
310 be_timer_pop(T_RA_COLOR);
312 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "color");
314 /* Create the ifg with the selected flavor */
315 be_timer_push(T_RA_IFG);
316 chordal_env->ifg = be_create_ifg(chordal_env);
317 be_timer_pop(T_RA_IFG);
319 if (stat_ev_enabled) {
321 be_node_stats_t node_stats;
323 be_ifg_stat(irg, chordal_env->ifg, &stat);
324 stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
325 stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
326 stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
328 be_collect_node_stats(&node_stats, irg);
329 be_subtract_node_stats(&node_stats, &last_node_stats);
331 stat_ev_dbl("bechordal_perms_before_coal",
332 node_stats[BE_STAT_PERMS]);
333 stat_ev_dbl("bechordal_copies_before_coal",
334 node_stats[BE_STAT_COPIES]);
337 be_timer_push(T_RA_COPYMIN);
338 co_driver(chordal_env);
339 be_timer_pop(T_RA_COPYMIN);
341 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "copymin");
343 /* ssa destruction */
344 be_timer_push(T_RA_SSA);
345 be_ssa_destruction(chordal_env);
346 be_timer_pop(T_RA_SSA);
348 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "ssadestr");
350 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
351 be_timer_push(T_VERIFY);
352 be_ssa_destruction_check(chordal_env);
353 be_timer_pop(T_VERIFY);
356 /* the ifg exists only if there are allocatable regs */
357 be_ifg_free(chordal_env->ifg);
360 /* free some always allocated data structures */
361 pmap_destroy(chordal_env->border_heads);
362 bitset_free(chordal_env->allocatable_regs);
366 * Performs chordal register allocation for each register class on given irg.
368 * @param irg the graph
369 * @return Structure containing timer for the single phases or NULL if no
372 static void be_ra_chordal_main(ir_graph *irg)
374 const arch_env_t *arch_env = be_get_irg_arch_env(irg);
377 be_chordal_env_t chordal_env;
380 be_timer_push(T_RA_OTHER);
382 be_timer_push(T_RA_PROLOG);
384 be_assure_liveness(irg);
386 chordal_env.obst = &obst;
387 chordal_env.opts = &options;
388 chordal_env.irg = irg;
389 chordal_env.border_heads = NULL;
390 chordal_env.ifg = NULL;
391 chordal_env.allocatable_regs = NULL;
395 be_timer_pop(T_RA_PROLOG);
397 if (stat_ev_enabled) {
398 be_collect_node_stats(&last_node_stats, irg);
401 /* use one of the generic spiller */
403 /* Perform the following for each register class. */
404 for (j = 0, m = arch_env->n_register_classes; j < m; ++j) {
405 post_spill_env_t pse;
406 const arch_register_class_t *cls = &arch_env->register_classes[j];
408 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
412 stat_ev_ctx_push_str("bechordal_cls", cls->name);
414 if (stat_ev_enabled) {
415 be_do_stat_reg_pressure(irg, cls);
418 pse.cenv = chordal_env;
420 pre_spill(&pse, cls);
422 be_timer_push(T_RA_SPILL);
423 be_do_spill(irg, cls);
424 be_timer_pop(T_RA_SPILL);
426 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "spill");
430 if (stat_ev_enabled) {
431 be_node_stats_t node_stats;
433 be_collect_node_stats(&node_stats, irg);
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 be_timer_push(T_VERIFY);
443 if (chordal_env.opts->vrfy_option == BE_CH_VRFY_WARN) {
444 be_verify_register_allocation(irg);
445 } else if (chordal_env.opts->vrfy_option == BE_CH_VRFY_ASSERT) {
446 assert(be_verify_register_allocation(irg)
447 && "Register allocation invalid");
449 be_timer_pop(T_VERIFY);
451 be_timer_push(T_RA_EPILOG);
452 lower_nodes_after_ra(irg, options.lower_perm_opt == BE_CH_LOWER_PERM_COPY);
453 dump(BE_CH_DUMP_LOWER, irg, NULL, "belower-after-ra");
455 obstack_free(&obst, NULL);
456 be_liveness_invalidate(be_get_irg_liveness(irg));
457 be_timer_pop(T_RA_EPILOG);
459 be_timer_pop(T_RA_OTHER);
462 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main)
463 void be_init_chordal_main(void)
465 static be_ra_t be_ra_chordal_allocator = {
469 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
470 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
471 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
473 be_register_allocator("chordal", &be_ra_chordal_allocator);
475 lc_opt_add_table(chordal_grp, be_chordal_options);
476 be_add_module_list_opt(chordal_grp, "coloring", "select coloring methode", &colorings, (void**) &selected_coloring);