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 #include "error.h"
  57
  58 #include "bechordal_t.h"
  59 #include "beabi.h"
  60 #include "beutil.h"
  61 #include "besched.h"
  62 #include "besched.h"
  63 #include "belive_t.h"
  64 #include "bearch.h"
  65 #include "beifg.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 #include "bedump_minir.h"
  74 #include "bestack.h"
  75
  76 #include "bespillslots.h"
  77 #include "bespill.h"
  78 #include "belower.h"
  79
  80 #include "becopystat.h"
  81 #include "becopyopt.h"
  82 #include "bessadestr.h"
  83 #include "beverify.h"
  84 #include "benode.h"
  85
  86 #include "bepbqpcoloring.h"
  87
  88 static be_ra_chordal_opts_t options = {
  89         BE_CH_DUMP_NONE,
  90         BE_CH_LOWER_PERM_SWAP,
  91         BE_CH_VRFY_WARN,
  92         "",
  93         ""
  94 };
  95
  96 typedef struct post_spill_env_t {
  97         be_chordal_env_t            cenv;
  98         ir_graph                    *irg;
  99         const arch_register_class_t *cls;
 100         double                      pre_spill_cost;
 101 } post_spill_env_t;
 102
 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 },
 106         { NULL, 0 }
 107 };
 108
 109 static const lc_opt_enum_int_items_t lower_perm_stat_items[] = {
 110         { NULL, 0 }
 111 };
 112
 113 static const lc_opt_enum_int_items_t dump_items[] = {
 114         { "none",       BE_CH_DUMP_NONE       },
 115         { "spill",      BE_CH_DUMP_SPILL      },
 116         { "live",       BE_CH_DUMP_LIVE       },
 117         { "color",      BE_CH_DUMP_COLOR      },
 118         { "copymin",    BE_CH_DUMP_COPYMIN    },
 119         { "ssadestr",   BE_CH_DUMP_SSADESTR   },
 120         { "tree",       BE_CH_DUMP_TREE_INTV  },
 121         { "constr",     BE_CH_DUMP_CONSTR     },
 122         { "lower",      BE_CH_DUMP_LOWER      },
 123         { "spillslots", BE_CH_DUMP_SPILLSLOTS },
 124         { "appel",      BE_CH_DUMP_APPEL      },
 125         { "all",        BE_CH_DUMP_ALL        },
 126         { NULL, 0 }
 127 };
 128
 129 static const lc_opt_enum_int_items_t be_ch_vrfy_items[] = {
 130         { "off",    BE_CH_VRFY_OFF    },
 131         { "warn",   BE_CH_VRFY_WARN   },
 132         { "assert", BE_CH_VRFY_ASSERT },
 133         { NULL, 0 }
 134 };
 135
 136 static lc_opt_enum_int_var_t lower_perm_var = {
 137         &options.lower_perm_opt, lower_perm_items
 138 };
 139
 140 static lc_opt_enum_int_var_t dump_var = {
 141         &options.dump_flags, dump_items
 142 };
 143
 144 static lc_opt_enum_int_var_t be_ch_vrfy_var = {
 145         &options.vrfy_option, be_ch_vrfy_items
 146 };
 147
 148 static char minir_file[256] = "";
 149
 150 static const lc_opt_table_entry_t be_chordal_options[] = {
 151         LC_OPT_ENT_ENUM_PTR ("perm",          "perm lowering options", &lower_perm_var),
 152         LC_OPT_ENT_ENUM_MASK("dump",          "select dump phases", &dump_var),
 153         LC_OPT_ENT_ENUM_PTR ("verify",        "verify options", &be_ch_vrfy_var),
 154         LC_OPT_ENT_STR      ("minirout",      "dump MinIR to file", minir_file, sizeof(minir_file)),
 155         LC_OPT_LAST
 156 };
 157
 158 static be_module_list_entry_t *colorings = NULL;
 159 static const be_ra_chordal_coloring_t *selected_coloring = NULL;
 160
 161 void be_register_chordal_coloring(const char *name, be_ra_chordal_coloring_t *coloring)
 162 {
 163         if (selected_coloring == NULL)
 164                 selected_coloring = coloring;
 165
 166         be_add_module_to_list(&colorings, name, coloring);
 167 }
 168
 169 static void be_ra_chordal_coloring(be_chordal_env_t *env)
 170 {
 171         assert(selected_coloring != NULL);
 172         if (selected_coloring != NULL) {
 173                 selected_coloring->allocate(env);
 174         }
 175 }
 176
 177 static void dump(unsigned mask, ir_graph *irg,
 178                                  const arch_register_class_t *cls,
 179                                  const char *suffix)
 180 {
 181         if ((options.dump_flags & mask) == mask) {
 182                 if (cls) {
 183                         char buf[256];
 184                         snprintf(buf, sizeof(buf), "%s-%s", cls->name, suffix);
 185                         dump_ir_graph(irg, buf);
 186                 } else {
 187                         dump_ir_graph(irg, suffix);
 188                 }
 189         }
 190 }
 191
 192 /**
 193  * Checks for every reload if its user can perform the load on itself.
 194  */
 195 static void memory_operand_walker(ir_node *irn, void *env)
 196 {
 197         const ir_edge_t  *edge, *ne;
 198         ir_node          *block;
 199         ir_node          *spill;
 200
 201         (void)env;
 202
 203         if (! be_is_Reload(irn))
 204                 return;
 205
 206         /* only use memory operands, if the reload is only used by 1 node */
 207         if (get_irn_n_edges(irn) > 1)
 208                 return;
 209
 210         spill = be_get_Reload_mem(irn);
 211         block = get_nodes_block(irn);
 212
 213         foreach_out_edge_safe(irn, edge, ne) {
 214                 ir_node *src = get_edge_src_irn(edge);
 215                 int     pos  = get_edge_src_pos(edge);
 216
 217                 assert(src && "outedges broken!");
 218
 219                 if (get_nodes_block(src) == block && arch_possible_memory_operand(src, pos)) {
 220                         arch_perform_memory_operand(src, spill, pos);
 221                 }
 222         }
 223
 224         /* kill the Reload */
 225         if (get_irn_n_edges(irn) == 0) {
 226                 sched_remove(irn);
 227                 set_irn_n(irn, be_pos_Reload_mem, new_Bad());
 228                 set_irn_n(irn, be_pos_Reload_frame, new_Bad());
 229         }
 230 }
 231
 232 /**
 233  * Starts a walk for memory operands if supported by the backend.
 234  */
 235 void check_for_memory_operands(ir_graph *irg)
 236 {
 237         irg_walk_graph(irg, NULL, memory_operand_walker, NULL);
 238 }
 239
 240
 241 static be_node_stats_t last_node_stats;
 242
 243 /**
 244  * Perform things which need to be done per register class before spilling.
 245  */
 246 static void pre_spill(post_spill_env_t *pse, const arch_register_class_t *cls)
 247 {
 248         be_chordal_env_t *chordal_env = &pse->cenv;
 249         ir_graph         *irg         = pse->irg;
 250         ir_exec_freq     *exec_freq   = be_get_irg_exec_freq(irg);
 251
 252         pse->cls                   = cls;
 253         chordal_env->cls           = cls;
 254         chordal_env->border_heads  = pmap_create();
 255         chordal_env->ignore_colors = bitset_malloc(chordal_env->cls->n_regs);
 256
 257         be_assure_liveness(irg);
 258         be_liveness_assure_chk(be_get_irg_liveness(irg));
 259
 260         stat_ev_do(pse->pre_spill_cost = be_estimate_irg_costs(irg, exec_freq));
 261
 262         /* put all ignore registers into the ignore register set. */
 263         be_put_ignore_regs(irg, pse->cls, chordal_env->ignore_colors);
 264
 265         be_timer_push(T_RA_CONSTR);
 266         be_pre_spill_prepare_constr(irg, chordal_env->cls);
 267         be_timer_pop(T_RA_CONSTR);
 268
 269         dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "constr-pre");
 270 }
 271
 272 /**
 273  * Perform things which need to be done per register class after spilling.
 274  */
 275 static void post_spill(post_spill_env_t *pse, int iteration)
 276 {
 277         be_chordal_env_t *chordal_env = &pse->cenv;
 278         ir_graph         *irg         = pse->irg;
 279         ir_exec_freq     *exec_freq   = be_get_irg_exec_freq(irg);
 280         int               colors_n    = arch_register_class_n_regs(chordal_env->cls);
 281         int               allocatable_regs
 282                 = colors_n - be_put_ignore_regs(irg, chordal_env->cls, NULL);
 283
 284         /* some special classes contain only ignore regs, no work to be done */
 285         if (allocatable_regs > 0) {
 286                 stat_ev_dbl("bechordal_spillcosts", be_estimate_irg_costs(irg, exec_freq) - pse->pre_spill_cost);
 287
 288                 /*
 289                         If we have a backend provided spiller, post spill is
 290                         called in a loop after spilling for each register class.
 291                         But we only need to fix stack nodes once in this case.
 292                 */
 293                 be_timer_push(T_RA_SPILL_APPLY);
 294                 check_for_memory_operands(irg);
 295                 if (iteration == 0) {
 296                         be_abi_fix_stack_nodes(irg);
 297                 }
 298                 be_timer_pop(T_RA_SPILL_APPLY);
 299
 300
 301                 /* verify schedule and register pressure */
 302                 be_timer_push(T_VERIFY);
 303                 if (chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) {
 304                         be_verify_schedule(irg);
 305                         be_verify_register_pressure(irg, pse->cls);
 306                 } else if (chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) {
 307                         assert(be_verify_schedule(irg) && "Schedule verification failed");
 308                         assert(be_verify_register_pressure(irg, pse->cls)
 309                                 && "Register pressure verification failed");
 310                 }
 311                 be_timer_pop(T_VERIFY);
 312
 313                 /* Color the graph. */
 314                 be_timer_push(T_RA_COLOR);
 315                 be_ra_chordal_coloring(chordal_env);
 316                 be_timer_pop(T_RA_COLOR);
 317
 318                 dump(BE_CH_DUMP_CONSTR, irg, pse->cls, "color");
 319
 320                 /* Create the ifg with the selected flavor */
 321                 be_timer_push(T_RA_IFG);
 322                 chordal_env->ifg = be_create_ifg(chordal_env);
 323                 be_timer_pop(T_RA_IFG);
 324
 325                 stat_ev_if {
 326                         be_ifg_stat_t   stat;
 327                         be_node_stats_t node_stats;
 328
 329                         be_ifg_stat(irg, chordal_env->ifg, &stat);
 330                         stat_ev_dbl("bechordal_ifg_nodes", stat.n_nodes);
 331                         stat_ev_dbl("bechordal_ifg_edges", stat.n_edges);
 332                         stat_ev_dbl("bechordal_ifg_comps", stat.n_comps);
 333
 334                         be_collect_node_stats(&node_stats, irg);
 335                         be_subtract_node_stats(&node_stats, &last_node_stats);
 336
 337                         stat_ev_dbl("bechordal_perms_before_coal",
 338                                         node_stats[BE_STAT_PERMS]);
 339                         stat_ev_dbl("bechordal_copies_before_coal",
 340                                         node_stats[BE_STAT_COPIES]);
 341                 }
 342
 343                 be_timer_push(T_RA_COPYMIN);
 344                 if (minir_file[0] != '\0') {
 345                         FILE *out;
 346
 347                         if (strcmp(minir_file, "-") == 0) {
 348                                 out = stdout;
 349                         } else {
 350                                 out = fopen(minir_file, "w");
 351                                 if (out == NULL) {
 352                                         panic("Cound't open minir output '%s'", minir_file);
 353                                 }
 354                         }
 355
 356                         be_export_minir(out, irg);
 357                         if (out != stdout)
 358                                 fclose(out);
 359                 }
 360                 co_driver(chordal_env);
 361                 be_timer_pop(T_RA_COPYMIN);
 362
 363                 dump(BE_CH_DUMP_COPYMIN, irg, pse->cls, "copymin");
 364
 365                 /* ssa destruction */
 366                 be_timer_push(T_RA_SSA);
 367                 be_ssa_destruction(chordal_env);
 368                 be_timer_pop(T_RA_SSA);
 369
 370                 dump(BE_CH_DUMP_SSADESTR, irg, pse->cls, "ssadestr");
 371
 372                 if (chordal_env->opts->vrfy_option != BE_CH_VRFY_OFF) {
 373                         be_timer_push(T_VERIFY);
 374                         be_ssa_destruction_check(chordal_env);
 375                         be_timer_pop(T_VERIFY);
 376                 }
 377
 378                 /* the ifg exists only if there are allocatable regs */
 379                 be_ifg_free(chordal_env->ifg);
 380         }
 381
 382         /* free some always allocated data structures */
 383         pmap_destroy(chordal_env->border_heads);
 384         bitset_free(chordal_env->ignore_colors);
 385 }
 386
 387 /**
 388  * Performs chordal register allocation for each register class on given irg.
 389  *
 390  * @param irg    the graph
 391  * @return Structure containing timer for the single phases or NULL if no
 392  *         timing requested.
 393  */
 394 static void be_ra_chordal_main(ir_graph *irg)
 395 {
 396         const arch_env_t *arch_env = be_get_irg_arch_env(irg);
 397         int               j;
 398         int               m;
 399         be_chordal_env_t  chordal_env;
 400         struct obstack    obst;
 401
 402         be_timer_push(T_RA_OTHER);
 403
 404         be_timer_push(T_RA_PROLOG);
 405
 406         be_assure_liveness(irg);
 407
 408         chordal_env.obst          = &obst;
 409         chordal_env.opts          = &options;
 410         chordal_env.irg           = irg;
 411         chordal_env.border_heads  = NULL;
 412         chordal_env.ifg           = NULL;
 413         chordal_env.ignore_colors = NULL;
 414
 415         obstack_init(&obst);
 416
 417         be_timer_pop(T_RA_PROLOG);
 418
 419         stat_ev_if {
 420                 be_collect_node_stats(&last_node_stats, irg);
 421         }
 422
 423         /* use one of the generic spiller */
 424
 425         /* Perform the following for each register class. */
 426         for (j = 0, m = arch_env_get_n_reg_class(arch_env); j < m; ++j) {
 427                 post_spill_env_t pse;
 428                 const arch_register_class_t *cls
 429                         = arch_env_get_reg_class(arch_env, j);
 430
 431                 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
 432                         continue;
 433
 434
 435                 stat_ev_ctx_push_str("bechordal_cls", cls->name);
 436
 437                 stat_ev_if {
 438                         be_do_stat_reg_pressure(irg, cls);
 439                 }
 440
 441                 memcpy(&pse.cenv, &chordal_env, sizeof(chordal_env));
 442                 pse.irg = irg;
 443                 pre_spill(&pse, cls);
 444
 445                 be_timer_push(T_RA_SPILL);
 446                 be_do_spill(irg, cls);
 447                 be_timer_pop(T_RA_SPILL);
 448
 449                 dump(BE_CH_DUMP_SPILL, irg, pse.cls, "spill");
 450
 451                 post_spill(&pse, 0);
 452
 453                 stat_ev_if {
 454                         be_node_stats_t node_stats;
 455
 456                         be_collect_node_stats(&node_stats, irg);
 457                         be_subtract_node_stats(&node_stats, &last_node_stats);
 458                         be_emit_node_stats(&node_stats, "bechordal_");
 459
 460                         be_copy_node_stats(&last_node_stats, &node_stats);
 461                         stat_ev_ctx_pop("bechordal_cls");
 462                 }
 463         }
 464
 465         be_timer_push(T_VERIFY);
 466         if (chordal_env.opts->vrfy_option == BE_CH_VRFY_WARN) {
 467                 be_verify_register_allocation(irg);
 468         } else if (chordal_env.opts->vrfy_option == BE_CH_VRFY_ASSERT) {
 469                 assert(be_verify_register_allocation(irg)
 470                                 && "Register allocation invalid");
 471         }
 472         be_timer_pop(T_VERIFY);
 473
 474         be_timer_push(T_RA_EPILOG);
 475         lower_nodes_after_ra(irg,
 476                              options.lower_perm_opt&BE_CH_LOWER_PERM_COPY ? 1 : 0);
 477         dump(BE_CH_DUMP_LOWER, irg, NULL, "belower-after-ra");
 478
 479         obstack_free(&obst, NULL);
 480         be_liveness_invalidate(be_get_irg_liveness(irg));
 481         be_timer_pop(T_RA_EPILOG);
 482
 483         be_timer_pop(T_RA_OTHER);
 484 }
 485
 486 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal_main);
 487 void be_init_chordal_main(void)
 488 {
 489         static be_ra_t be_ra_chordal_allocator = {
 490                 be_ra_chordal_main,
 491         };
 492
 493         lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
 494         lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
 495         lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
 496
 497         be_register_allocator("chordal", &be_ra_chordal_allocator);
 498
 499         lc_opt_add_table(chordal_grp, be_chordal_options);
 500         be_add_module_list_opt(chordal_grp, "coloring", "select coloring methode", &colorings, (void**) &selected_coloring);
 501 }