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

   1 /**
   2  * Author:      Daniel Grund
   3  * Date:                12.04.2005
   4  * Copyright:   (c) Universitaet Karlsruhe
   5  * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
   6  */
   7 #ifdef HAVE_CONFIG_H
   8 #include "config.h"
   9 #endif
  10 #ifdef HAVE_ALLOCA_H
  11 #include <alloca.h>
  12 #endif
  13 #ifdef HAVE_MALLOC_H
  14 #include <malloc.h>
  15 #endif
  16
  17 #include <libcore/lc_timing.h>
  18
  19 #include "xmalloc.h"
  20 #include "debug.h"
  21 #include "pmap.h"
  22 #include "irgraph.h"
  23 #include "irgwalk.h"
  24 #include "irprog.h"
  25 #include "irloop_t.h"
  26 #include "iredges_t.h"
  27 #include "phiclass.h"
  28
  29 #include "bearch.h"
  30 #include "beutil.h"
  31 #include "becopyopt_t.h"
  32 #include "becopystat.h"
  33
  34
  35
  36 static firm_dbg_module_t *dbg = NULL;
  37
  38 /**
  39  * Determines a maximum weighted independent set with respect to
  40  * the interference and conflict edges of all nodes in a qnode.
  41  */
  42 static int ou_max_ind_set_costs(unit_t *ou) {
  43         be_chordal_env_t *chordal_env = ou->co->cenv;
  44         ir_node **safe, **unsafe;
  45         int i, o, safe_count, safe_costs, unsafe_count, *unsafe_costs;
  46         bitset_t *curr;
  47         int max, pos, curr_weight, best_weight = 0;
  48
  49         /* assign the nodes into two groups.
  50          * safe: node has no interference, hence it is in every max stable set.
  51          * unsafe: node has an interference
  52          */
  53         safe = alloca((ou->node_count-1) * sizeof(*safe));
  54         safe_costs = 0;
  55         safe_count = 0;
  56         unsafe = alloca((ou->node_count-1) * sizeof(*unsafe));
  57         unsafe_costs = alloca((ou->node_count-1) * sizeof(*unsafe_costs));
  58         unsafe_count = 0;
  59         for(i=1; i<ou->node_count; ++i) {
  60                 int is_safe = 1;
  61                 for(o=1; o<ou->node_count; ++o) {
  62                         if (i==o)
  63                                 continue;
  64                         if (nodes_interfere(chordal_env, ou->nodes[i], ou->nodes[o])) {
  65                                 unsafe_costs[unsafe_count] = ou->costs[i];
  66                                 unsafe[unsafe_count] = ou->nodes[i];
  67                                 ++unsafe_count;
  68                                 is_safe = 0;
  69                                 break;
  70                         }
  71                 }
  72                 if (is_safe) {
  73                         safe_costs += ou->costs[i];
  74                         safe[safe_count++] = ou->nodes[i];
  75                 }
  76         }
  77
  78
  79         /* now compute the best set out of the unsafe nodes*/
  80         if (unsafe_count > MIS_HEUR_TRIGGER) {
  81                 bitset_t *best = bitset_alloca(unsafe_count);
  82                 /* Heuristik: Greedy trial and error form index 0 to unsafe_count-1 */
  83                 for (i=0; i<unsafe_count; ++i) {
  84                         bitset_set(best, i);
  85                         /* check if it is a stable set */
  86                         for (o=bitset_next_set(best, 0); o!=-1 && o<i; o=bitset_next_set(best, o+1))
  87                                 if (nodes_interfere(chordal_env, unsafe[i], unsafe[o])) {
  88                                         bitset_clear(best, i); /* clear the bit and try next one */
  89                                         break;
  90                                 }
  91                 }
  92                 /* compute the weight */
  93                 bitset_foreach(best, pos)
  94                         best_weight += unsafe_costs[pos];
  95         } else {
  96                 /* Exact Algorithm: Brute force */
  97                 curr = bitset_alloca(unsafe_count);
  98                 bitset_set_all(curr);
  99                 while ((max = bitset_popcnt(curr)) != 0) {
 100                         /* check if curr is a stable set */
 101                         for (i=bitset_next_set(curr, 0); i!=-1; i=bitset_next_set(curr, i+1))
 102                                 for (o=bitset_next_set(curr, i+1); o!=-1; o=bitset_next_set(curr, o+1)) /* !!!!! difference to qnode_max_ind_set(): NOT (curr, i) */
 103                                                 if (nodes_interfere(chordal_env, unsafe[i], unsafe[o]))
 104                                                         goto no_stable_set;
 105
 106                         /* if we arrive here, we have a stable set */
 107                         /* compute the weigth of the stable set*/
 108                         curr_weight = 0;
 109                         bitset_foreach(curr, pos)
 110                                 curr_weight += unsafe_costs[pos];
 111
 112                         /* any better ? */
 113                         if (curr_weight > best_weight) {
 114                                 best_weight = curr_weight;
 115                         }
 116
 117         no_stable_set:
 118                         bitset_minus1(curr);
 119                 }
 120         }
 121
 122         return safe_costs+best_weight;
 123 }
 124
 125 static void co_collect_units(ir_node *irn, void *env) {
 126         copy_opt_t *co = env;
 127         unit_t *unit;
 128         arch_register_req_t req;
 129
 130         if (!is_curr_reg_class(co, irn))
 131                 return;
 132         if (!co_is_optimizable(co->aenv, irn, &req))
 133                 return;
 134
 135         /* Init a new unit */
 136         unit = xcalloc(1, sizeof(*unit));
 137         unit->co = co;
 138         unit->node_count = 1;
 139         INIT_LIST_HEAD(&unit->queue);
 140
 141         /* Phi with some/all of its arguments */
 142         if (is_Reg_Phi(irn)) {
 143                 int i, arity;
 144
 145                 /* init */
 146                 arity = get_irn_arity(irn);
 147                 unit->nodes = xmalloc((arity+1) * sizeof(*unit->nodes));
 148                 unit->costs = xmalloc((arity+1) * sizeof(*unit->costs));
 149                 unit->nodes[0] = irn;
 150
 151                 /* fill */
 152                 for (i=0; i<arity; ++i) {
 153                         int o, arg_pos;
 154                         ir_node *arg = get_irn_n(irn, i);
 155
 156                         assert(is_curr_reg_class(co, arg) && "Argument not in same register class.");
 157                         if (arg == irn)
 158                                 continue;
 159                         if (nodes_interfere(co->cenv, irn, arg)) {
 160                                 unit->inevitable_costs += co->get_costs(irn, arg, i);
 161                                 continue;
 162                         }
 163
 164                         /* Else insert the argument of the phi to the members of this ou */
 165                         DBG((dbg, LEVEL_1, "\t   Member: %+F\n", arg));
 166
 167                         /* Check if arg has occurred at a prior position in the arg/list */
 168                         arg_pos = 0;
 169                         for (o=0; o<unit->node_count; ++o)
 170                                 if (unit->nodes[o] == arg) {
 171                                         arg_pos = o;
 172                                         break;
 173                                 }
 174
 175                         if (!arg_pos) { /* a new argument */
 176                                 /* insert node, set costs */
 177                                 unit->nodes[unit->node_count] = arg;
 178                                 unit->costs[unit->node_count] = co->get_costs(irn, arg, i);
 179                                 unit->node_count++;
 180                         } else { /* arg has occured before in same phi */
 181                                 /* increase costs for existing arg */
 182                                 unit->costs[arg_pos] += co->get_costs(irn, arg, i);
 183                         }
 184                 }
 185                 unit->nodes = xrealloc(unit->nodes, unit->node_count * sizeof(*unit->nodes));
 186                 unit->costs = xrealloc(unit->costs, unit->node_count * sizeof(*unit->costs));
 187         } else
 188
 189         /* Proj of a perm with corresponding arg */
 190         if (is_Perm_Proj(co->aenv, irn)) {
 191                 assert(!nodes_interfere(co->cenv, irn, get_Copy_src(irn)));
 192                 unit->nodes = xmalloc(2 * sizeof(*unit->nodes));
 193                 unit->costs = xmalloc(2 * sizeof(*unit->costs));
 194                 unit->node_count = 2;
 195                 unit->nodes[0] = irn;
 196                 unit->nodes[1] = get_Copy_src(irn);
 197                 unit->costs[1] = co->get_costs(irn, unit->nodes[1], -1);
 198         } else
 199
 200         /* Src == Tgt of a 2-addr-code instruction */
 201         if (is_2addr_code(co->aenv, irn, &req)) {
 202                 ir_node *other = req.other_same;
 203                 if (!nodes_interfere(co->cenv, irn, other)) {
 204                         unit->nodes = xmalloc(2 * sizeof(*unit->nodes));
 205                         unit->costs = xmalloc(2 * sizeof(*unit->costs));
 206                         unit->node_count = 2;
 207                         unit->nodes[0] = irn;
 208                         unit->nodes[1] = other;
 209                         unit->costs[1] = co->get_costs(irn, other, -120480);
 210                 }
 211         } else
 212                 assert(0 && "This is not an optimizable node!");
 213
 214         /* Insert the new unit at a position according to its costs */
 215         if (unit->node_count > 1) {
 216                 int i;
 217                 struct list_head *tmp;
 218
 219                 /* Determine the maximum costs this unit can cause: all_nodes_cost */
 220                 for(i=1; i<unit->node_count; ++i) {
 221                         unit->sort_key = MAX(unit->sort_key, unit->costs[i]);
 222                         unit->all_nodes_costs += unit->costs[i];
 223                 }
 224
 225                 /* Determine the minimal costs this unit will cause: min_nodes_costs */
 226                 unit->min_nodes_costs += unit->all_nodes_costs - ou_max_ind_set_costs(unit);
 227
 228                 /* Insert the new ou according to its sort_key */
 229                 tmp = &co->units;
 230                 while (tmp->next != &co->units && list_entry_units(tmp->next)->sort_key > unit->sort_key)
 231                         tmp = tmp->next;
 232                 list_add(&unit->units, tmp);
 233         } else {
 234                 free(unit);
 235         }
 236 }
 237
 238 void be_copy_opt_init(void) {
 239         dbg = firm_dbg_register("ir.be.copyoptmain");
 240 }
 241
 242 copy_opt_t *new_copy_opt(be_chordal_env_t *chordal_env, int (*get_costs)(ir_node*, ir_node*, int)) {
 243         const char *s1, *s2, *s3;
 244         int len;
 245         copy_opt_t *co;
 246
 247         dbg = firm_dbg_register("ir.be.copyopt");
 248
 249         co = xcalloc(1, sizeof(*co));
 250         co->cenv = chordal_env;
 251         co->aenv = chordal_env->birg->main_env->arch_env;
 252         co->irg = chordal_env->irg;
 253         co->cls = chordal_env->cls;
 254         co->get_costs = get_costs;
 255
 256         s1 = get_irp_prog_name();
 257         s2 = get_entity_name(get_irg_entity(co->irg));
 258         s3 = chordal_env->cls->name;
 259         len = strlen(s1) + strlen(s2) + strlen(s3) + 5;
 260         co->name = xmalloc(len);
 261         snprintf(co->name, len, "%s__%s__%s", s1, s2, s3);
 262
 263         DBG((dbg, LEVEL_1, "\tCollecting optimization units\n"));
 264         INIT_LIST_HEAD(&co->units);
 265         irg_walk_graph(co->irg, co_collect_units, NULL, co);
 266         return co;
 267 }
 268
 269 void free_copy_opt(copy_opt_t *co) {
 270         unit_t *curr, *tmp;
 271         xfree(co->name);
 272         list_for_each_entry_safe(unit_t, curr, tmp, &co->units, units) {
 273                 xfree(curr->nodes);
 274                 xfree(curr->costs);
 275                 xfree(curr);
 276         }
 277 }
 278
 279 int is_optimizable_arg(const copy_opt_t *co, ir_node *irn) {
 280         const ir_edge_t *edge;
 281
 282         if (arch_irn_is_ignore(co->aenv, irn))
 283                 return 0;
 284
 285         foreach_out_edge(irn, edge) {
 286                 ir_node *n = edge->src;
 287
 288                 if (!nodes_interfere(co->cenv, irn, n) || irn == n) {
 289                         arch_register_req_t req;
 290                         arch_get_register_req(co->aenv, &req, n, -1);
 291
 292                         if(is_Reg_Phi(n) ||
 293                            is_Perm(co->aenv, n) ||
 294                            (arch_register_req_is(&req, should_be_same) && req.other_same == irn)
 295                           )
 296                                 return 1;
 297                 }
 298         }
 299
 300         return 0;
 301 }
 302
 303 int get_costs_loop_depth(ir_node *root, ir_node* arg, int pos) {
 304         int cost = 0;
 305         ir_loop *loop;
 306         ir_node *root_block = get_nodes_block(root);
 307
 308         if (is_Phi(root)) {
 309                 /* for phis the copies are placed in the corresponding pred-block */
 310                 loop = get_irn_loop(get_Block_cfgpred_block(root_block, pos));
 311         } else {
 312                 /* a perm places the copy in the same block as it resides */
 313                 loop = get_irn_loop(root_block);
 314         }
 315         if (loop) {
 316                 int d = get_loop_depth(loop);
 317                 cost = d*d;
 318         }
 319         return cost+1;
 320 }
 321
 322 int get_costs_all_one(ir_node *root, ir_node* arg, int pos) {
 323         return 1;
 324 }
 325
 326 int co_get_max_copy_costs(const copy_opt_t *co) {
 327         int i, res = 0;
 328         unit_t *curr;
 329
 330         list_for_each_entry(unit_t, curr, &co->units, units) {
 331                 res += curr->inevitable_costs;
 332                 for (i=1; i<curr->node_count; ++i)
 333                         res += curr->costs[i];
 334         }
 335         return res;
 336 }
 337
 338 int co_get_inevit_copy_costs(const copy_opt_t *co) {
 339         int res = 0;
 340         unit_t *curr;
 341
 342         list_for_each_entry(unit_t, curr, &co->units, units)
 343                 res += curr->inevitable_costs;
 344         return res;
 345 }
 346
 347 int co_get_copy_costs(const copy_opt_t *co) {
 348         int i, res = 0;
 349         unit_t *curr;
 350
 351         list_for_each_entry(unit_t, curr, &co->units, units) {
 352                 int root_col = get_irn_col(co, curr->nodes[0]);
 353                 DBG((dbg, LEVEL_1, "  %3d costs for root %+F color %d\n", curr->inevitable_costs, curr->nodes[0], root_col));
 354                 res += curr->inevitable_costs;
 355                 for (i=1; i<curr->node_count; ++i) {
 356                         int arg_col = get_irn_col(co, curr->nodes[i]);
 357                         if (root_col != arg_col) {
 358                                 DBG((dbg, LEVEL_1, "  %3d for arg %+F color %d\n", curr->costs[i], curr->nodes[i], arg_col));
 359                                 res += curr->costs[i];
 360                         }
 361                 }
 362         }
 363         return res;
 364 }
 365
 366 int co_get_lower_bound(const copy_opt_t *co) {
 367         int res = 0;
 368         unit_t *curr;
 369         list_for_each_entry(unit_t, curr, &co->units, units)
 370                 res += curr->inevitable_costs + curr->min_nodes_costs;
 371         return res;
 372 }
 373
 374
 375
 376 #define DO_HEUR
 377 #undef DO_CLASSES
 378 #undef DO_ILP
 379
 380
 381 /**
 382  * Helpers for saving and restoring colors of nodes.
 383  * Used to get dependable and comparable benchmark results.
 384  */
 385 #if (defined(DO_HEUR) && defined(DO_BETTER)) || (defined(DO_HEUR) && defined(DO_ILP)) || (defined(DO_BETTER) && defined(DO_ILP))
 386
 387 typedef struct color_saver {
 388         arch_env_t *arch_env;
 389         be_chordal_env_t *chordal_env;
 390         pmap *saved_colors;
 391         int flag; /* 0 save, 1 load */
 392 } color_save_t;
 393
 394 static void save_load(ir_node *irn, void *env) {
 395         color_save_t *saver = env;
 396         if (saver->chordal_env->cls == arch_get_irn_reg_class(saver->arch_env, irn, -1)) {
 397                 if (saver->flag == 0) { /* save */
 398                         const arch_register_t *reg = arch_get_irn_register(saver->arch_env, irn);
 399                         pmap_insert(saver->saved_colors, irn, (void *) reg);
 400                 } else { /*load */
 401                         arch_register_t *reg = pmap_get(saver->saved_colors, irn);
 402                         arch_set_irn_register(saver->arch_env, irn, reg);
 403                 }
 404         }
 405 }
 406
 407 static void save_colors(color_save_t *color_saver) {
 408         color_saver->flag = 0;
 409         irg_walk_graph(color_saver->chordal_env->irg, save_load, NULL, color_saver);
 410 }
 411
 412 static void load_colors(color_save_t *color_saver) {
 413         color_saver->flag = 1;
 414         irg_walk_graph(color_saver->chordal_env->irg, save_load, NULL, color_saver);
 415 }
 416
 417 #endif /* Need save/load stuff */
 418
 419
 420
 421 void co_compare_solvers(be_chordal_env_t *chordal_env) {
 422         copy_opt_t *co;
 423
 424 #ifdef DO_STAT
 425         lc_timer_t *timer;
 426         color_save_t saver;
 427         int costs, costs_inevit, costs_init, costs_heur, costs_classes, costs_ilp, lower_bound;
 428 #endif
 429
 430         co = new_copy_opt(chordal_env, get_costs_loop_depth);
 431         DBG((dbg, LEVEL_1, "----> CO: %s\n", co->name));
 432         phi_class_compute(chordal_env->irg);
 433
 434
 435 #ifdef DO_STAT
 436 #if (defined(DO_HEUR) && defined(DO_BETTER)) || (defined(DO_HEUR) && defined(DO_ILP)) || (defined(DO_BETTER) && defined(DO_ILP))
 437                 saver.arch_env = chordal_env->main_env->arch_env;
 438                 saver.chordal_env = chordal_env;
 439                 saver.saved_colors = pmap_create();
 440                 save_colors(&saver);
 441 #endif
 442
 443                 costs_inevit = co_get_inevit_copy_costs(co);
 444                 lower_bound  = co_get_lower_bound(co);
 445                 costs_init   = co_get_copy_costs(co);
 446
 447                 DBG((dbg, LEVEL_1, "Inevit Costs: %3d\n", costs_inevit));
 448                 DBG((dbg, LEVEL_1, "Lower Bound: %3d\n", lower_bound));
 449                 DBG((dbg, LEVEL_1, "Init costs: %3d\n", costs_init));
 450
 451                 copystat_add_inevit_costs(costs_inevit);
 452                 copystat_add_init_costs(costs_init);
 453                 copystat_add_max_costs(co_get_max_copy_costs(co));
 454 #endif
 455
 456
 457 #ifdef DO_HEUR
 458 #ifdef DO_STAT
 459         timer = lc_timer_register("heur", NULL);
 460         lc_timer_reset_and_start(timer);
 461 #endif
 462
 463         co_solve_heuristic(co);
 464
 465 #ifdef DO_STAT
 466         lc_timer_stop(timer);
 467         costs_heur = co_get_copy_costs(co);
 468         DBG((dbg, LEVEL_1, "Heur costs: %3d\n", costs_heur));
 469         copystat_add_heur_time(lc_timer_elapsed_msec(timer));
 470         copystat_add_heur_costs(costs_heur);
 471         assert(lower_bound <= costs_heur);
 472 #endif
 473 #endif /* DO_HEUR */
 474
 475
 476
 477 #ifdef DO_CLASSES
 478 #ifdef DO_STAT
 479 #ifdef DO_HEUR
 480         load_colors(&saver);
 481 #endif
 482         timer = lc_timer_register("classes", NULL);
 483         lc_timer_reset_and_start(timer);
 484 #endif
 485
 486         co_classes_opt(co);
 487
 488 #ifdef DO_STAT
 489         lc_timer_stop(timer);
 490         costs_classes = co_get_copy_costs(co);
 491         DBG((dbg, LEVEL_1, "Classes costs: %3d\n", costs_classes));
 492         copystat_add_classes_time(lc_timer_elapsed_msec(timer));
 493         copystat_add_classes_costs(costs_heur);
 494         assert(lower_bound <= costs_classes);
 495 #endif
 496 #endif /* DO_CLASSES */
 497
 498
 499
 500 #ifdef DO_ILP
 501 #ifdef DO_STAT
 502 #if defined(DO_HEUR) || defined(DO_CLASSES)
 503         load_colors(&saver);
 504 #endif
 505 #endif
 506
 507         co_solve_ilp1(co, 60.0);
 508
 509 #ifdef DO_STAT
 510         costs_ilp = co_get_copy_costs(co);
 511         DBG((dbg, LEVEL_1, "Opt  costs: %3d\n", costs_ilp));
 512         copystat_add_opt_costs(costs_ilp);
 513         assert(lower_bound <= costs_ilp);
 514 #endif
 515 #endif /* DO_ILP */
 516
 517
 518 #ifdef DO_STAT
 519 #if (defined(DO_HEUR) && defined(DO_BETTER)) || (defined(DO_HEUR) && defined(DO_ILP)) || (defined(DO_BETTER) && defined(DO_ILP))
 520         pmap_destroy(saver.saved_colors);
 521 #endif
 522 #endif
 523         free_copy_opt(co);
 524 }