nsz Git - libfirm/blob - ir/be/bechordal_main.c

   1 /*
   2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   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.
  10  *
  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.
  14  *
  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
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @brief       Driver for the chordal register allocator.
  23  * @author      Sebastian Hack
  24  * @date        29.11.2005
  25  * @version     $Id$
  26  */
  27 #include "config.h"
  28
  29 #include <stdlib.h>
  30 #include <time.h>
  31
  32 #include "obst.h"
  33 #include "pset.h"
  34 #include "list.h"
  35 #include "bitset.h"
  36 #include "iterator.h"
  37
  38 #include "lc_opts.h"
  39 #include "lc_opts_enum.h"
  40
  41 #include "ircons_t.h"
  42 #include "irmode_t.h"
  43 #include "irgraph_t.h"
  44 #include "irprintf_t.h"
  45 #include "irgwalk.h"
  46 #include "ircons.h"
  47 #include "irdump.h"
  48 #include "irdom.h"
  49 #include "ircons.h"
  50 #include "irbitset.h"
  51 #include "irnode.h"
  52 #include "ircons.h"
  53 #include "debug.h"
  54 #include "execfreq.h"
  55 #include "iredges_t.h"
  56
  57 #include "bechordal_t.h"
  58 #include "beabi.h"
  59 #include "beutil.h"
  60 #include "besched.h"
  61 #include "besched.h"
  62 #include "belive_t.h"
  63 #include "bearch.h"
  64 #include "beifg_t.h"
  65 #include "beifg_impl.h"
  66 #include "benode.h"
  67 #include "bestatevent.h"
  68 #include "bestat.h"
  69 #include "bemodule.h"
  70 #include "be_t.h"
  71 #include "bera.h"
  72 #include "beirg.h"
  73
  74 #include "bespillslots.h"
  75 #include "bespill.h"
  76 #include "belower.h"
  77
  78 #include "becopystat.h"
  79 #include "becopyopt.h"
  80 #include "bessadestr.h"
  81 #include "beverify.h"
  82 #include "benode.h"
  83
  84 #include "bepbqpcoloring.h"
  85
  86 static be_ra_chordal_opts_t options = {
  87         BE_CH_DUMP_NONE,
  88         BE_CH_LOWER_PERM_SWAP,
  89         BE_CH_VRFY_WARN,
  90         "",
  91         ""
  92 };
  93
  94 typedef struct _post_spill_env_t {
  95         be_chordal_env_t            cenv;
  96         be_irg_t                    *birg;
  97         const arch_register_class_t *cls;
  98         double                      pre_spill_cost;
  99 } post_spill_env_t;
 100
 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 },
 104         { NULL, 0 }
 105 };
 106
 107 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
 108         { NULL, 0 }
 109 };
 110
 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        },
 124         { NULL, 0 }
 125 };
 126
 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 },
 131         { NULL, 0 }
 132 };
 133
 134 static lc_opt_enum_int_var_t lower_perm_var = {
 135         &options.lower_perm_opt, lower_perm_items
 136 };
 137
 138 static lc_opt_enum_int_var_t dump_var = {
 139         &options.dump_flags, dump_items
 140 };
 141
 142 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
 143         &options.vrfy_option, be_ch_vrfy_items
 144 };
 145
 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 ("verify",        "verify options", &be_ch_vrfy_var),
 150         LC_OPT_LAST
 151 };
 152
 153 static be_module_list_entry_t *colorings = NULL;
 154 static const be_ra_chordal_coloring_t *selected_coloring = NULL;
 155
 156 void be_register_chordal_coloring(const char *name, be_ra_chordal_coloring_t *coloring)
 157 {
 158         if (selected_coloring == NULL)
 159                 selected_coloring = coloring;
 160
 161         be_add_module_to_list(&colorings, name, coloring);
 162 }
 163
 164 void be_ra_chordal_coloring(be_chordal_env_t *env)
 165 {
 166         assert(selected_coloring != NULL);
 167         if(selected_coloring != NULL) {
 168                 selected_coloring->allocate(env);
 169         }
 170 }
 171
 172
 173 static void dump(unsigned mask, ir_graph *irg,
 174                                  const arch_register_class_t *cls,
 175                                  const char *suffix,
 176                                  void (*dump_func)(ir_graph *, const char *))
 177 {
 178         if((options.dump_flags & mask) == mask) {
 179                 if (cls) {
 180                         char buf[256];
 181                         snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
 182                         be_dump(irg, buf, dump_func);
 183                 }
 184                 else
 185                         be_dump(irg, suffix, dump_func);
 186         }
 187 }
 188
 189 /**
 190  * Checks for every reload if its user can perform the load on itself.
 191  */
 192 static void memory_operand_walker(ir_node *irn, void *env)
 193 {
 194         const ir_edge_t  *edge, *ne;
 195         ir_node          *block;
 196         ir_node          *spill;
 197
 198         (void)env;
 199
 200         if (! be_is_Reload(irn))
 201                 return;
 202
 203         /* only use memory operands, if the reload is only used by 1 node */
 204         if(get_irn_n_edges(irn) > 1)
 205                 return;
 206
 207         spill = be_get_Reload_mem(irn);
 208         block = get_nodes_block(irn);
 209
 210         foreach_out_edge_safe(irn, edge, ne) {
 211                 ir_node *src = get_edge_src_irn(edge);
 212                 int     pos  = get_edge_src_pos(edge);
 213
 214                 assert(src && "outedges broken!");
 215
 216                 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
 217                         arch_perform_memory_operand(src, spill, pos);
 218                 }
 219         }
 220
 221         /* kill the Reload */
 222         if (get_irn_n_edges(irn) == 0) {
 223                 sched_remove(irn);
 224                 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
 225                 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
 226         }
 227 }
 228
 229 /**
 230  * Starts a walk for memory operands if supported by the backend.
 231  */
 232 void check_for_memory_operands(ir_graph *irg)
 233 {
 234         irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
 235 }
 236
 237
 238 static be_node_stats_t last_node_stats;
 239
 240 /**
 241  * Perform things which need to be done per register class before spilling.
 242  */
 243 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
 244 {
 245         be_chordal_env_t    *chordal_env = &pse->cenv;
 246         be_irg_t            *birg        = pse->birg;
 247         ir_graph            *irg         = be_get_birg_irg(birg);
 248
 249         pse->cls                   = cls;
 250         chordal_env->cls           = cls;
 251         chordal_env->border_heads  = pmap_create();
 252         chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
 253
 254         be_assure_liveness(birg);
 255         be_liveness_assure_chk(be_get_birg_liveness(birg));
 256
 257         stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, birg->exec_freq));
 258
 259         /* put all ignore registers into the ignore register set. */
 260         be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
 261
 262         BE_TIMER_PUSH(t_ra_constr);
 263         be_pre_spill_prepare_constr(chordal_env->birg, chordal_env->cls);
 264         BE_TIMER_POP(t_ra_constr);
 265
 266         dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
 267 }
 268
 269 /**
 270  * Perform things which need to be done per register class after spilling.
 271  */
 272 static void post_spill(post_spill_env_t *pse, int iteration) {
 273         be_chordal_env_t    *chordal_env = &pse->cenv;
 274         be_irg_t            *birg        = pse->birg;
 275         ir_graph            *irg         = birg->irg;
 276         int                  colors_n    = arch_register_class_n_regs(chordal_env->cls);
 277         int             allocatable_regs = colors_n - be_put_ignore_regs(birg, chordal_env->cls, NULL);
 278
 279         /* some special classes contain only ignore regs, no work to be done */
 280         if (allocatable_regs > 0) {
 281                 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, birg->exec_freq) - pse->pre_spill_cost);
 282
 283                 /*
 284                         If we have a backend provided spiller, post spill is
 285                         called in a loop after spilling for each register class.
 286                         But we only need to fix stack nodes once in this case.
 287                 */
 288                 BE_TIMER_PUSH(t_ra_spill_apply);
 289                 check_for_memory_operands(irg);
 290                 if (iteration == 0) {
 291                         be_abi_fix_stack_nodes(birg->abi);
 292                 }
 293                 BE_TIMER_POP(t_ra_spill_apply);
 294
 295
 296                 /* verify schedule and register pressure */
 297                 BE_TIMER_PUSH(t_verify);
 298                 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
 299                         be_verify_schedule(birg);
 300                         be_verify_register_pressure(birg, pse->cls, irg);
 301                 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
 302                         assert(be_verify_schedule(birg) && "Schedule verification failed");
 303                         assert(be_verify_register_pressure(birg, pse->cls, irg)
 304                                 && "Register pressure verification failed");
 305                 }
 306                 BE_TIMER_POP(t_verify);
 307
 308                 /* Color the graph. */
 309                 BE_TIMER_PUSH(t_ra_color);
 310                 be_ra_chordal_coloring(chordal_env);
 311                 BE_TIMER_POP(t_ra_color);
 312
 313                 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
 314
 315                 /* Create the ifg with the selected flavor */
 316                 BE_TIMER_PUSH(t_ra_ifg);
 317                 chordal_env->ifg = be_create_ifg(chordal_env);
 318                 BE_TIMER_POP(t_ra_ifg);
 319
 320                 stat_ev_if {
 321                         be_ifg_stat_t   stat;
 322                         be_node_stats_t node_stats;
 323
 324                         be_ifg_stat(birg, chordal_env->ifg, &stat);
 325                         stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
 326                         stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
 327                         stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
 328
 329                         be_collect_node_stats(&node_stats, birg);
 330                         be_subtract_node_stats(&node_stats, &last_node_stats);
 331
 332                         stat_ev_dbl("bechordal_perms_before_coal",
 333                                         node_stats[BE_STAT_PERMS]);
 334                         stat_ev_dbl("bechordal_copies_before_coal",
 335                                         node_stats[BE_STAT_COPIES]);
 336                 }
 337
 338                 BE_TIMER_PUSH(t_ra_copymin);
 339                 co_driver(chordal_env);
 340                 BE_TIMER_POP(t_ra_copymin);
 341
 342                 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
 343
 344                 /* ssa destruction */
 345                 BE_TIMER_PUSH(t_ra_ssa);
 346                 be_ssa_destruction(chordal_env);
 347                 BE_TIMER_POP(t_ra_ssa);
 348
 349                 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
 350
 351                 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
 352                         BE_TIMER_PUSH(t_verify);
 353                         be_ssa_destruction_check(chordal_env);
 354                         BE_TIMER_POP(t_verify);
 355                 }
 356
 357                 /* the ifg exists only if there are allocatable regs */
 358                 be_ifg_free(chordal_env->ifg);
 359         }
 360
 361         /* free some always allocated data structures */
 362         pmap_destroy(chordal_env->border_heads);
 363         bitset_free(chordal_env->ignore_colors);
 364 }
 365
 366 /**
 367  * Performs chordal register allocation for each register class on given irg.
 368  *
 369  * @param birg  Backend irg object
 370  * @return Structure containing timer for the single phases or NULL if no timing requested.
 371  */
 372 static void be_ra_chordal_main(be_irg_t *birg)
 373 {
 374         const arch_env_t *arch_env = birg->main_env->arch_env;
 375         ir_graph         *irg      = birg->irg;
 376         int               j;
 377         int               m;
 378         be_chordal_env_t  chordal_env;
 379         struct obstack    obst;
 380
 381         BE_TIMER_PUSH(t_ra_other);
 382
 383         BE_TIMER_PUSH(t_ra_prolog);
 384
 385         be_assure_liveness(birg);
 386
 387         chordal_env.obst          = &obst;
 388         chordal_env.opts          = &options;
 389         chordal_env.irg           = irg;
 390         chordal_env.birg          = birg;
 391         chordal_env.border_heads  = NULL;
 392         chordal_env.ifg           = NULL;
 393         chordal_env.ignore_colors = NULL;
 394
 395         obstack_init(&obst);
 396
 397         BE_TIMER_POP(t_ra_prolog);
 398
 399         stat_ev_if {
 400                 be_collect_node_stats(&last_node_stats, birg);
 401         }
 402
 403         if (! arch_code_generator_has_spiller(birg->cg)) {
 404                 /* use one of the generic spiller */
 405
 406                 /* Perform the following for each register class. */
 407                 for (j = 0, m = arch_env_get_n_reg_class(arch_env); j < m; ++j) {
 408                         post_spill_env_t pse;
 409                         const arch_register_class_t *cls
 410                                 = arch_env_get_reg_class(arch_env, j);
 411
 412                         if(arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
 413                                 continue;
 414
 415
 416                         stat_ev_ctx_push_str("bechordal_cls", cls->name);
 417
 418                         stat_ev_if {
 419                                 be_do_stat_reg_pressure(birg, cls);
 420                         }
 421
 422                         memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
 423                         pse.birg = birg;
 424                         pre_spill(&pse, cls);
 425
 426                         BE_TIMER_PUSH(t_ra_spill);
 427                         be_do_spill(birg, cls);
 428                         BE_TIMER_POP(t_ra_spill);
 429
 430                         dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill",
 431                              dump_ir_block_graph_sched);
 432
 433                         post_spill(&pse, 0);
 434
 435                         stat_ev_if {
 436                                 be_node_stats_t node_stats;
 437
 438                                 be_collect_node_stats(&node_stats, birg);
 439                                 be_subtract_node_stats(&node_stats, &last_node_stats);
 440                                 be_emit_node_stats(&node_stats, "bechordal_");
 441
 442                                 be_copy_node_stats(&last_node_stats, &node_stats);
 443                                 stat_ev_ctx_pop("bechordal_cls");
 444                         }
 445                 }
 446         } else {
 447                 post_spill_env_t *pse;
 448
 449                 /* the backend has its own spiller */
 450                 m = arch_env_get_n_reg_class(arch_env);
 451
 452                 pse = ALLOCAN(post_spill_env_t, m);
 453
 454                 for (j = 0; j < m; ++j) {
 455                         memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
 456                         pse[j].birg = birg;
 457                         pre_spill(&pse[j], pse[j].cls);
 458                 }
 459
 460                 BE_TIMER_PUSH(t_ra_spill);
 461                 arch_code_generator_spill(birg->cg, birg);
 462                 BE_TIMER_POP(t_ra_spill);
 463                 dump(BE_CH_DUMP_SPILL, irg, NULL, "-spill", dump_ir_block_graph_sched);
 464
 465                 for (j = 0; j < m; ++j) {
 466                         post_spill(&pse[j], j);
 467                 }
 468         }
 469
 470         BE_TIMER_PUSH(t_verify);
 471         if (chordal_env.opts->vrfy_option == BE_CH_VRFY_WARN) {
 472                 be_verify_register_allocation(birg);
 473         } else if(chordal_env.opts->vrfy_option == BE_CH_VRFY_ASSERT) {
 474                 assert(be_verify_register_allocation(birg)
 475                                 && "Register allocation invalid");
 476         }
 477         BE_TIMER_POP(t_verify);
 478
 479         BE_TIMER_PUSH(t_ra_epilog);
 480         lower_nodes_after_ra(birg, options.lower_perm_opt & BE_CH_LOWER_PERM_COPY ? 1 : 0);
 481         dump(BE_CH_DUMP_LOWER, irg, NULL, "-belower-after-ra", dump_ir_block_graph_sched);
 482
 483         obstack_free(&obst, NULL);
 484         be_liveness_invalidate(be_get_birg_liveness(birg));
 485         BE_TIMER_POP(t_ra_epilog);
 486
 487         BE_TIMER_POP(t_ra_other);
 488 }
 489
 490 void be_init_chordal_main(void)
 491 {
 492         static be_ra_t be_ra_chordal_allocator = {
 493                 be_ra_chordal_main,
 494         };
 495
 496         lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
 497         lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
 498         lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
 499
 500         be_register_allocator("chordal", &be_ra_chordal_allocator);
 501
 502         lc_opt_add_table(chordal_grp, be_chordal_options);
 503         be_add_module_list_opt(chordal_grp, "coloring", "select coloring methode", &colorings, (void**) &selected_coloring);
 504 }
 505
 506 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);