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_t.h"
  62 #include "belive_t.h"
  63 #include "bearch_t.h"
  64 #include "beifg_t.h"
  65 #include "beifg_impl.h"
  66 #include "benode_t.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_t.h"
  73
  74 #include "bespillslots.h"
  75 #include "bespilloptions.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_t.h"
  83
  84 static be_ra_chordal_opts_t options = {
  85         BE_CH_DUMP_NONE,
  86         BE_CH_LOWER_PERM_SWAP,
  87         BE_CH_VRFY_WARN,
  88         "",
  89         ""
  90 };
  91
  92 typedef struct _post_spill_env_t {
  93         be_chordal_env_t            cenv;
  94         be_irg_t                    *birg;
  95         const arch_register_class_t *cls;
  96         double                      pre_spill_cost;
  97 } post_spill_env_t;
  98
  99 static be_options_t  *main_opts;
 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 ("vrfy",          "verify options", &be_ch_vrfy_var),
 150         LC_OPT_LAST
 151 };
 152
 153 static void dump(unsigned mask, ir_graph *irg,
 154                                  const arch_register_class_t *cls,
 155                                  const char *suffix,
 156                                  void (*dump_func)(ir_graph *, const char *))
 157 {
 158         if((options.dump_flags & mask) == mask) {
 159                 if (cls) {
 160                         char buf[256];
 161                         snprintf(buf, sizeof(buf), "-%s%s", cls->name, suffix);
 162                         be_dump(irg, buf, dump_func);
 163                 }
 164                 else
 165                         be_dump(irg, suffix, dump_func);
 166         }
 167 }
 168
 169 /**
 170  * Checks for every reload if its user can perform the load on itself.
 171  */
 172 static void memory_operand_walker(ir_node *irn, void *env)
 173 {
 174         const ir_edge_t  *edge, *ne;
 175         ir_node          *block;
 176         ir_node          *spill;
 177
 178         (void)env;
 179
 180         if (! be_is_Reload(irn))
 181                 return;
 182
 183         /* only use memory operands, if the reload is only used by 1 node */
 184         if(get_irn_n_edges(irn) > 1)
 185                 return;
 186
 187         spill = be_get_Reload_mem(irn);
 188         block = get_nodes_block(irn);
 189
 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);
 193
 194                 assert(src && "outedges broken!");
 195
 196                 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
 197                         arch_perform_memory_operand(src, spill, pos);
 198                 }
 199         }
 200
 201         /* kill the Reload */
 202         if (get_irn_n_edges(irn) == 0) {
 203                 sched_remove(irn);
 204                 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
 205                 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
 206         }
 207 }
 208
 209 /**
 210  * Starts a walk for memory operands if supported by the backend.
 211  */
 212 static INLINE void check_for_memory_operands(ir_graph *irg)
 213 {
 214         irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
 215 }
 216
 217
 218 static be_node_stats_t last_node_stats;
 219
 220 /**
 221  * Perform things which need to be done per register class before spilling.
 222  */
 223 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
 224 {
 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;
 229
 230         pse->cls                   = cls;
 231         chordal_env->cls           = cls;
 232         chordal_env->border_heads  = pmap_create();
 233         chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
 234
 235         be_assure_liveness(birg);
 236         be_liveness_assure_chk(be_get_birg_liveness(birg));
 237
 238         stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, main_env->arch_env, birg->exec_freq));
 239
 240         /* put all ignore registers into the ignore register set. */
 241         be_put_ignore_regs(birg, pse->cls, chordal_env->ignore_colors);
 242
 243         BE_TIMER_PUSH(t_ra_constr);
 244         be_pre_spill_prepare_constr(chordal_env);
 245         BE_TIMER_POP(t_ra_constr);
 246
 247         dump(BE_CH_DUMP_CONSTR, birg->irg, pse->cls, "-constr-pre", dump_ir_block_graph_sched);
 248 }
 249
 250 /**
 251  * Perform things which need to be done per register class after spilling.
 252  */
 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);
 260
 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);
 264
 265                 /*
 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.
 269                 */
 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);
 274                 }
 275                 BE_TIMER_POP(t_ra_spill_apply);
 276
 277                 BE_TIMER_PUSH(t_verify);
 278
 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");
 287                 }
 288                 BE_TIMER_POP(t_verify);
 289
 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);
 294
 295                 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "-color", dump_ir_block_graph_sched);
 296
 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);
 301
 302                 stat_ev_if {
 303                         be_ifg_stat_t   stat;
 304                         be_node_stats_t node_stats;
 305
 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);
 310
 311                         be_collect_node_stats(&node_stats, birg);
 312                         be_subtract_node_stats(&node_stats, &last_node_stats);
 313
 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]);
 318                 }
 319
 320                 /* copy minimization */
 321                 BE_TIMER_PUSH(t_ra_copymin);
 322                 co_driver(chordal_env);
 323                 BE_TIMER_POP(t_ra_copymin);
 324
 325                 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "-copymin", dump_ir_block_graph_sched);
 326
 327
 328                 /* ssa destruction */
 329                 BE_TIMER_PUSH(t_ra_ssa);
 330                 be_ssa_destruction(chordal_env);
 331                 BE_TIMER_POP(t_ra_ssa);
 332
 333                 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "-ssadestr", dump_ir_block_graph_sched);
 334
 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);
 339                 }
 340
 341                 /* the ifg exists only if there are allocatable regs */
 342                 be_ifg_free(chordal_env->ifg);
 343         }
 344
 345         /* free some always allocated data structures */
 346         pmap_destroy(chordal_env->border_heads);
 347         bitset_free(chordal_env->ignore_colors);
 348 }
 349
 350 /**
 351  * Performs chordal register allocation for each register class on given irg.
 352  *
 353  * @param birg  Backend irg object
 354  * @return Structure containing timer for the single phases or NULL if no timing requested.
 355  */
 356 static void be_ra_chordal_main(be_irg_t *birg)
 357 {
 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;
 361         int                 j, m;
 362         be_chordal_env_t    chordal_env;
 363         struct obstack      obst;
 364
 365         main_opts = main_env->options;
 366
 367         BE_TIMER_PUSH(t_ra_other);
 368
 369         BE_TIMER_PUSH(t_ra_prolog);
 370
 371         be_assure_liveness(birg);
 372
 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;
 380
 381         obstack_init(&obst);
 382
 383         BE_TIMER_POP(t_ra_prolog);
 384
 385         stat_ev_if {
 386                 be_collect_node_stats(&last_node_stats, birg);
 387         }
 388
 389         if (! arch_code_generator_has_spiller(birg->cg)) {
 390                 /* use one of the generic spiller */
 391
 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);
 397
 398                         if(arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
 399                                 continue;
 400
 401
 402                         stat_ev_ctx_push_str("bechordal_cls", cls->name);
 403
 404                         stat_ev_if {
 405                                 be_do_stat_reg_pressure(birg, cls);
 406                         }
 407
 408                         memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
 409                         pse.birg = birg;
 410                         pre_spill(&pse, cls);
 411
 412                         BE_TIMER_PUSH(t_ra_spill);
 413                         be_do_spill(birg, cls);
 414                         BE_TIMER_POP(t_ra_spill);
 415
 416                         dump(BE_CH_DUMP_SPILL, irg, pse.cls, "-spill",
 417                              dump_ir_block_graph_sched);
 418
 419                         post_spill(&pse, 0);
 420
 421                         stat_ev_if {
 422                                 be_node_stats_t node_stats;
 423
 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_");
 427
 428                                 be_copy_node_stats(&last_node_stats, &node_stats);
 429                                 stat_ev_ctx_pop("bechordal_cls");
 430                         }
 431                 }
 432         } else {
 433                 post_spill_env_t *pse;
 434
 435                 /* the backend has its own spiller */
 436                 m = arch_env_get_n_reg_class(arch_env);
 437
 438                 pse = alloca(m * sizeof(pse[0]));
 439
 440                 for (j = 0; j < m; ++j) {
 441                         memcpy(&pse[j].cenv, &chordal_env, sizeof(chordal_env));
 442                         pse[j].birg = birg;
 443                         pre_spill(&pse[j], pse[j].cls);
 444                 }
 445
 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);
 450
 451                 for (j = 0; j < m; ++j) {
 452                         post_spill(&pse[j], j);
 453                 }
 454         }
 455
 456         BE_TIMER_PUSH(t_verify);
 457         be_verify_register_allocation(birg);
 458         BE_TIMER_POP(t_verify);
 459
 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);
 463
 464         obstack_free(&obst, NULL);
 465         be_liveness_invalidate(be_get_birg_liveness(birg));
 466         BE_TIMER_POP(t_ra_epilog);
 467
 468         BE_TIMER_POP(t_ra_other);
 469 }
 470
 471 static be_ra_t be_ra_chordal_allocator = {
 472         be_ra_chordal_main,
 473 };
 474
 475 void be_init_chordal_main(void)
 476 {
 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");
 480
 481         lc_opt_add_table(chordal_grp, be_chordal_options);
 482
 483         be_register_allocator("chordal", &be_ra_chordal_allocator);
 484 }
 485
 486 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);