nsz Git - libfirm/blob - ir/be/benewalloc.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       New approach to allocation and copy coalescing
  23  * @author      Matthias Braun
  24  * @date        14.2.2009
  25  * @version     $Id$
  26  *
  27  * ... WE NEED A NAME FOR THIS ...
  28  *
  29  * Only a proof of concept at this moment...
  30  *
  31  * The idea is to allocate registers in 2 passes:
  32  * 1. A first pass to determine "prefered" registers for live-ranges. This
  33  *    calculates for each register and each live-range a value indicating
  34  *    the usefullness. (You can roughly think of the value as the negative
  35  *    costs needed for copies when the value is in the specific registers...)
  36  *
  37  * 2. Walk blocks and assigns registers in a greedy fashion. Prefering registers
  38  *    with high preferences. When register constraints are not met, add copies
  39  *    and split live-ranges.
  40  *
  41  * TODO:
  42  *  - output constraints are not ensured. The algorithm fails to copy values
  43  *    away, so the registers for constrained outputs are free.
  44  *  - must_be_different constraint is not respected
  45  *  - No parallel copies at basic block borders are created, no additional phis
  46  *    created after copies have been inserted.
  47  *  - Phi color assignment should give bonus points towards registers already
  48  *    assigned at predecessors.
  49  *  - think about a smarter sequence of visiting the blocks. Sorted by
  50  *    execfreq might be good, or looptree from inner to outermost loops going
  51  *    over blocks in a reverse postorder
  52  */
  53 #include "config.h"
  54
  55 #include <float.h>
  56
  57 #include "obst.h"
  58 #include "irnode_t.h"
  59 #include "irgraph_t.h"
  60 #include "iredges_t.h"
  61 #include "ircons.h"
  62 #include "irgwalk.h"
  63 #include "execfreq.h"
  64
  65 #include "be.h"
  66 #include "bera.h"
  67 #include "belive_t.h"
  68 #include "bemodule.h"
  69 #include "bechordal_t.h"
  70 #include "besched_t.h"
  71 #include "beirg_t.h"
  72 #include "benode_t.h"
  73 #include "bespilloptions.h"
  74 #include "beverify.h"
  75
  76 #include "bipartite.h"
  77 #include "hungarian.h"
  78
  79 #define USE_FACTOR       1.0f
  80 #define DEF_FACTOR       1.0f
  81 #define NEIGHBOR_FACTOR  0.2f
  82 #define SHOULD_BE_SAME   1.0f
  83
  84 DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
  85
  86 static struct obstack               obst;
  87 static be_irg_t                    *birg;
  88 static ir_graph                    *irg;
  89 static const arch_register_class_t *cls;
  90 static be_lv_t                     *lv;
  91 static const ir_exec_freq          *execfreqs;
  92 static unsigned                     n_regs;
  93 static bitset_t                    *ignore_regs;
  94
  95 typedef struct assignment_t assignment_t;
  96 struct assignment_t {
  97         ir_node *value;            /**< currently assigned value */
  98 };
  99
 100 static assignment_t *assignments;
 101
 102 typedef struct allocation_info_t allocation_info_t;
 103 struct allocation_info_t {
 104         unsigned      last_uses;   /**< bitset indicating last uses (input pos) */
 105         assignment_t *current_assignment;
 106         float         prefs[0];    /**< register preferences */
 107 };
 108
 109 typedef struct reg_pref_t reg_pref_t;
 110 struct reg_pref_t {
 111         unsigned num;
 112         float    pref;
 113 };
 114
 115 static allocation_info_t *get_allocation_info(ir_node *node)
 116 {
 117         allocation_info_t *info;
 118         if (!irn_visited(node)) {
 119                 size_t size = sizeof(info[0]) + n_regs * sizeof(float);
 120                 info = obstack_alloc(&obst, size);
 121                 memset(info, 0, size);
 122                 set_irn_link(node, info);
 123                 mark_irn_visited(node);
 124         } else {
 125                 info = get_irn_link(node);
 126         }
 127
 128         return info;
 129 }
 130
 131 static void link_to(ir_node *copy, ir_node *value)
 132 {
 133         allocation_info_t *info = get_allocation_info(value);
 134         assert(!irn_visited(copy));
 135         set_irn_link(copy, info);
 136         mark_irn_visited(copy);
 137 }
 138
 139 static void give_penalties_for_limits(const ir_nodeset_t *live_nodes,
 140                                       float penalty, const unsigned* limited,
 141                                                                           ir_node *node)
 142 {
 143         ir_nodeset_iterator_t iter;
 144         unsigned              r;
 145         allocation_info_t     *info = get_allocation_info(node);
 146         ir_node               *neighbor;
 147
 148         /* give penalty for all forbidden regs */
 149         for (r = 0; r < n_regs; ++r) {
 150                 if (rbitset_is_set(limited, r))
 151                         continue;
 152
 153                 info->prefs[r] -= penalty;
 154         }
 155
 156         /* all other live values should get a penalty for allowed regs */
 157         if (live_nodes == NULL)
 158                 return;
 159
 160         /* TODO: reduce penalty if there are multiple allowed registers... */
 161         penalty *= NEIGHBOR_FACTOR;
 162         foreach_ir_nodeset(live_nodes, neighbor, iter) {
 163                 allocation_info_t *neighbor_info;
 164
 165                 /* TODO: if op is used on multiple inputs we might not do a
 166                  * continue here */
 167                 if (neighbor == node)
 168                         continue;
 169
 170                 neighbor_info = get_allocation_info(neighbor);
 171                 for (r = 0; r < n_regs; ++r) {
 172                         if (!rbitset_is_set(limited, r))
 173                                 continue;
 174
 175                         neighbor_info->prefs[r] -= penalty;
 176                 }
 177         }
 178 }
 179
 180 static void check_defs(const ir_nodeset_t *live_nodes, float weight,
 181                        ir_node *node)
 182 {
 183         const arch_register_req_t *req;
 184
 185         if (get_irn_mode(node) == mode_T) {
 186                 const ir_edge_t *edge;
 187                 foreach_out_edge(node, edge) {
 188                         ir_node *proj = get_edge_src_irn(edge);
 189                         check_defs(live_nodes, weight, proj);
 190                 }
 191                 return;
 192         }
 193
 194         if (!arch_irn_consider_in_reg_alloc(cls, node))
 195                 return;
 196
 197         req = arch_get_register_req_out(node);
 198         if (req->type & arch_register_req_type_limited) {
 199                 const unsigned *limited = req->limited;
 200                 float           penalty = weight * DEF_FACTOR;
 201                 give_penalties_for_limits(live_nodes, penalty, limited, node);
 202         }
 203
 204         if (req->type & arch_register_req_type_should_be_same) {
 205                 ir_node           *insn  = skip_Proj(node);
 206                 allocation_info_t *info  = get_allocation_info(node);
 207                 int                arity = get_irn_arity(insn);
 208                 int                i;
 209
 210                 float factor = 1.0f / rbitset_popcnt(&req->other_same, arity);
 211                 for (i = 0; i < arity; ++i) {
 212                         ir_node           *op;
 213                         unsigned          r;
 214                         allocation_info_t *op_info;
 215
 216                         if (!rbitset_is_set(&req->other_same, i))
 217                                 continue;
 218
 219                         op      = get_irn_n(insn, i);
 220                         op_info = get_allocation_info(op);
 221                         for (r = 0; r < n_regs; ++r) {
 222                                 if (bitset_is_set(ignore_regs, r))
 223                                         continue;
 224                                 op_info->prefs[r] += info->prefs[r] * factor;
 225                         }
 226                 }
 227         }
 228 }
 229
 230 static void analyze_block(ir_node *block, void *data)
 231 {
 232         float         weight = get_block_execfreq(execfreqs, block);
 233         ir_nodeset_t  live_nodes;
 234         ir_node      *node;
 235         (void) data;
 236
 237         ir_nodeset_init(&live_nodes);
 238         be_liveness_end_of_block(lv, cls, block, &live_nodes);
 239
 240         sched_foreach_reverse(block, node) {
 241                 allocation_info_t *info;
 242                 int               i, arity;
 243
 244                 if (is_Phi(node)) {
 245                         /* TODO: handle constrained phi-nodes */
 246                         break;
 247                 }
 248
 249                 /* TODO give/take penalties for should_be_same/different) */
 250                 check_defs(&live_nodes, weight, node);
 251
 252                 /* mark last uses */
 253                 arity = get_irn_arity(node);
 254                 /* I was lazy, and only allocated 1 unsigned
 255                    => maximum of 32 uses per node (rewrite if necessary) */
 256                 assert(arity <= (int) sizeof(unsigned) * 8);
 257
 258                 info = get_allocation_info(node);
 259                 for (i = 0; i < arity; ++i) {
 260                         ir_node *op = get_irn_n(node, i);
 261                         if (!arch_irn_consider_in_reg_alloc(cls, op))
 262                                 continue;
 263
 264                         /* last usage of a value? */
 265                         if (!ir_nodeset_contains(&live_nodes, op)) {
 266                                 rbitset_set(&info->last_uses, i);
 267                         }
 268                 }
 269
 270                 be_liveness_transfer(cls, node, &live_nodes);
 271
 272                 /* update weights based on usage constraints */
 273                 for (i = 0; i < arity; ++i) {
 274                         const arch_register_req_t *req;
 275                         const unsigned            *limited;
 276                         ir_node                   *op = get_irn_n(node, i);
 277
 278                         if (!arch_irn_consider_in_reg_alloc(cls, op))
 279                                 continue;
 280
 281                         req = arch_get_register_req(node, i);
 282                         if ((req->type & arch_register_req_type_limited) == 0)
 283                                 continue;
 284
 285                         /* TODO: give penalties to neighbors for precolored nodes! */
 286
 287                         limited = req->limited;
 288                         give_penalties_for_limits(&live_nodes, weight * USE_FACTOR, limited,
 289                                                   op);
 290                 }
 291         }
 292
 293         ir_nodeset_destroy(&live_nodes);
 294 }
 295
 296 static void use_reg(ir_node *node, const arch_register_t *reg)
 297 {
 298         unsigned      r          = arch_register_get_index(reg);
 299         assignment_t *assignment = &assignments[r];
 300         allocation_info_t *info;
 301
 302         assert(assignment->value == NULL);
 303         assignment->value = node;
 304
 305         info = get_allocation_info(node);
 306         info->current_assignment = assignment;
 307
 308         arch_set_irn_register(node, reg);
 309 }
 310
 311 static int compare_reg_pref(const void *e1, const void *e2)
 312 {
 313         const reg_pref_t *rp1 = (const reg_pref_t*) e1;
 314         const reg_pref_t *rp2 = (const reg_pref_t*) e2;
 315         if (rp1->pref < rp2->pref)
 316                 return 1;
 317         if (rp1->pref > rp2->pref)
 318                 return -1;
 319         return 0;
 320 }
 321
 322 static void fill_sort_candidates(reg_pref_t *regprefs,
 323                                  const allocation_info_t *info)
 324 {
 325         unsigned r;
 326
 327         for (r = 0; r < n_regs; ++r) {
 328                 float pref = info->prefs[r];
 329                 if (bitset_is_set(ignore_regs, r)) {
 330                         pref = -10000;
 331                 }
 332                 regprefs[r].num  = r;
 333                 regprefs[r].pref = pref;
 334         }
 335         /* TODO: use a stable sort here to avoid unnecessary register jumping */
 336         qsort(regprefs, n_regs, sizeof(regprefs[0]), compare_reg_pref);
 337 }
 338
 339 static void assign_reg(const ir_node *block, ir_node *node)
 340 {
 341         const arch_register_t     *reg;
 342         allocation_info_t         *info;
 343         const arch_register_req_t *req;
 344         reg_pref_t                *reg_prefs;
 345         unsigned                  i;
 346
 347         assert(arch_irn_consider_in_reg_alloc(cls, node));
 348
 349         /* preassigned register? */
 350         reg = arch_get_irn_register(node);
 351         if (reg != NULL) {
 352                 DB((dbg, LEVEL_2, "Preassignment %+F -> %s\n", node, reg->name));
 353                 use_reg(node, reg);
 354                 return;
 355         }
 356
 357         /* give should_be_same boni */
 358         info = get_allocation_info(node);
 359         req  = arch_get_register_req_out(node);
 360
 361         ir_node *in_node = skip_Proj(node);
 362         if (req->type & arch_register_req_type_should_be_same) {
 363                 float weight = get_block_execfreq(execfreqs, block);
 364                 int   arity  = get_irn_arity(in_node);
 365                 int   i;
 366
 367                 assert(arity <= (int) sizeof(req->other_same) * 8);
 368                 for (i = 0; i < arity; ++i) {
 369                         ir_node               *in;
 370                         const arch_register_t *reg;
 371                         unsigned               r;
 372                         if (!rbitset_is_set(&req->other_same, i))
 373                                 continue;
 374
 375                         in  = get_irn_n(in_node, i);
 376                         reg = arch_get_irn_register(in);
 377                         assert(reg != NULL);
 378                         r = arch_register_get_index(reg);
 379                         if (bitset_is_set(ignore_regs, r))
 380                                 continue;
 381                         info->prefs[r] += weight * SHOULD_BE_SAME;
 382                 }
 383         }
 384
 385         /* TODO: handle must_be_different */
 386
 387         /*  */
 388         DB((dbg, LEVEL_2, "Candidates for %+F:", node));
 389         reg_prefs = alloca(n_regs * sizeof(reg_prefs[0]));
 390         fill_sort_candidates(reg_prefs, info);
 391         for (i = 0; i < n_regs; ++i) {
 392                 unsigned               num = reg_prefs[i].num;
 393                 const arch_register_t *reg = arch_register_for_index(cls, num);
 394                 DB((dbg, LEVEL_2, " %s(%f)", reg->name, reg_prefs[i].pref));
 395         }
 396         DB((dbg, LEVEL_2, "\n"));
 397
 398         for (i = 0; i < n_regs; ++i) {
 399                 unsigned r = reg_prefs[i].num;
 400                 /* ignores should be last and we should have a non-ignore left */
 401                 assert(!bitset_is_set(ignore_regs, r));
 402                 /* already used? TODO: It might be better to copy the value occupying the register around here, find out when... */
 403                 if (assignments[r].value != NULL)
 404                         continue;
 405                 use_reg(node, arch_register_for_index(cls, r));
 406                 break;
 407         }
 408 }
 409
 410 static void free_reg_of_value(ir_node *node)
 411 {
 412         allocation_info_t *info;
 413         assignment_t      *assignment;
 414         unsigned          r;
 415
 416         if (!arch_irn_consider_in_reg_alloc(cls, node))
 417                 return;
 418
 419         info       = get_allocation_info(node);
 420         assignment = info->current_assignment;
 421
 422         assert(assignment != NULL);
 423
 424         r = assignment - assignments;
 425         DB((dbg, LEVEL_2, "Value %+F ended, freeing %s\n",
 426                 node, arch_register_for_index(cls, r)->name));
 427         assignment->value        = NULL;
 428         info->current_assignment = NULL;
 429 }
 430
 431 static unsigned get_current_reg(ir_node *node)
 432 {
 433         allocation_info_t *info       = get_allocation_info(node);
 434         assignment_t      *assignment = info->current_assignment;
 435         return assignment - assignments;
 436 }
 437
 438 static assignment_t *get_current_assignment(ir_node *node)
 439 {
 440         allocation_info_t *info = get_allocation_info(node);
 441         return info->current_assignment;
 442 }
 443
 444 static void permutate_values(ir_nodeset_t *live_nodes, ir_node *before,
 445                              unsigned *permutation)
 446 {
 447         ir_node *block, *perm;
 448         ir_node **in = ALLOCAN(ir_node*, n_regs);
 449         size_t    r;
 450
 451         int i = 0;
 452         for (r = 0; r < n_regs; ++r) {
 453                 unsigned     new_reg = permutation[r];
 454                 assignment_t *assignment;
 455                 ir_node      *value;
 456
 457                 if (new_reg == r)
 458                         continue;
 459
 460                 assignment = &assignments[r];
 461                 value      = assignment->value;
 462                 if (value == NULL) {
 463                         /* nothing to do here, reg is not live */
 464                         permutation[r] = r;
 465                         continue;
 466                 }
 467
 468                 in[i++] = value;
 469
 470                 free_reg_of_value(value);
 471                 ir_nodeset_remove(live_nodes, value);
 472         }
 473
 474         block = get_nodes_block(before);
 475         perm  = be_new_Perm(cls, irg, block, i, in);
 476
 477         sched_add_before(before, perm);
 478
 479         i = 0;
 480         for (r = 0; r < n_regs; ++r) {
 481                 unsigned new_reg = permutation[r];
 482                 ir_node  *value;
 483                 ir_mode  *mode;
 484                 ir_node  *proj;
 485                 const arch_register_t *reg;
 486
 487                 if (new_reg == r)
 488                         continue;
 489
 490                 value = in[i];
 491                 mode  = get_irn_mode(value);
 492                 proj  = new_r_Proj(irg, block, perm, mode, i);
 493
 494                 reg = arch_register_for_index(cls, new_reg);
 495
 496                 link_to(proj, value);
 497                 use_reg(proj, reg);
 498                 ir_nodeset_insert(live_nodes, proj);
 499
 500                 ++i;
 501         }
 502 }
 503
 504 /* free regs for values last used */
 505 static void free_last_uses(ir_nodeset_t *live_nodes, ir_node *node)
 506 {
 507         allocation_info_t *info  = get_allocation_info(node);
 508         int                arity = get_irn_arity(node);
 509         int                i;
 510         for (i = 0; i < arity; ++i) {
 511                 ir_node *op;
 512
 513                 if (!rbitset_is_set(&info->last_uses, i))
 514                         continue;
 515
 516                 op = get_irn_n(node, i);
 517                 free_reg_of_value(op);
 518                 ir_nodeset_remove(live_nodes, op);
 519         }
 520 }
 521
 522 static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node)
 523 {
 524         int arity = get_irn_arity(node);
 525         int i, dummy, res;
 526         hungarian_problem_t *bp;
 527         unsigned l, r, p;
 528         unsigned *assignment;
 529
 530         /* see if any use constraints are not met */
 531         bool good = true;
 532         for (i = 0; i < arity; ++i) {
 533                 ir_node                   *op = get_irn_n(node, i);
 534                 const arch_register_req_t *req;
 535                 const unsigned            *limited;
 536                 unsigned                  r;
 537
 538                 if (!arch_irn_consider_in_reg_alloc(cls, op))
 539                         continue;
 540
 541                 req = arch_get_register_req(node, i);
 542                 if ((req->type & arch_register_req_type_limited) == 0)
 543                         continue;
 544
 545                 limited = req->limited;
 546                 r       = get_current_reg(op);
 547                 if (!rbitset_is_set(limited, r)) {
 548                         good = false;
 549                         break;
 550                 }
 551         }
 552
 553         if (good)
 554                 return;
 555
 556         /* swap values around */
 557         bp = hungarian_new(n_regs, n_regs, HUNGARIAN_MATCH_PERFECT);
 558
 559         /* add all combinations, then remove not allowed ones */
 560         for (l = 0; l < n_regs; ++l) {
 561                 if (bitset_is_set(ignore_regs, l)) {
 562                         hungarian_add(bp, l, l, 90);
 563                         continue;
 564                 }
 565
 566                 for (r = 0; r < n_regs; ++r) {
 567                         if (bitset_is_set(ignore_regs, r))
 568                                 continue;
 569
 570                         hungarian_add(bp, l, r, l == r ? 90 : 89);
 571                 }
 572         }
 573
 574         for (i = 0; i < arity; ++i) {
 575                 ir_node                   *op = get_irn_n(node, i);
 576                 const arch_register_req_t *req;
 577                 const unsigned            *limited;
 578                 unsigned                  current_reg;
 579
 580                 if (!arch_irn_consider_in_reg_alloc(cls, op))
 581                         continue;
 582
 583                 req = arch_get_register_req(node, i);
 584                 if ((req->type & arch_register_req_type_limited) == 0)
 585                         continue;
 586
 587                 limited     = req->limited;
 588                 current_reg = get_current_reg(op);
 589                 for (r = 0; r < n_regs; ++r) {
 590                         if (rbitset_is_set(limited, r))
 591                                 continue;
 592                         hungarian_remv(bp, current_reg, r);
 593                 }
 594         }
 595
 596         hungarian_print_costmatrix(bp, 1);
 597         hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
 598
 599         assignment = ALLOCAN(unsigned, n_regs);
 600         res = hungarian_solve(bp, (int*) assignment, &dummy, 0);
 601         assert(res == 0);
 602
 603         printf("Swap result:");
 604         for (p = 0; p < n_regs; ++p) {
 605                 printf(" %d", assignment[p]);
 606         }
 607         printf("\n");
 608
 609         hungarian_free(bp);
 610
 611         permutate_values(live_nodes, node, assignment);
 612 }
 613
 614 static void allocate_coalesce_block(ir_node *block, void *data)
 615 {
 616         int                   i;
 617         ir_nodeset_t          live_nodes;
 618         ir_nodeset_iterator_t iter;
 619         ir_node               *node, *start;
 620
 621         /* clear assignments */
 622         memset(assignments, 0, n_regs * sizeof(assignments[0]));
 623
 624         (void) data;
 625
 626         /* collect live-in nodes and preassigned values */
 627         ir_nodeset_init(&live_nodes);
 628         be_lv_foreach(lv, block, be_lv_state_in, i) {
 629                 const arch_register_t *reg;
 630
 631                 node = be_lv_get_irn(lv, block, i);
 632                 if (!arch_irn_consider_in_reg_alloc(cls, node))
 633                         continue;
 634
 635                 ir_nodeset_insert(&live_nodes, node);
 636
 637                 /* fill in regs already assigned */
 638                 reg = arch_get_irn_register(node);
 639                 if (reg != NULL) {
 640                         use_reg(node, reg);
 641                 }
 642         }
 643
 644         /* handle phis... */
 645         node = sched_first(block);
 646         for ( ; is_Phi(node); node = sched_next(node)) {
 647                 const arch_register_t *reg;
 648
 649                 if (!arch_irn_consider_in_reg_alloc(cls, node))
 650                         continue;
 651
 652                 /* fill in regs already assigned */
 653                 reg = arch_get_irn_register(node);
 654                 if (reg != NULL) {
 655                         use_reg(node, reg);
 656                 } else {
 657                         /* TODO: give boni for registers already assigned at the
 658                            predecessors */
 659                 }
 660         }
 661         start = node;
 662
 663         /* assign regs for live-in values */
 664         foreach_ir_nodeset(&live_nodes, node, iter) {
 665                 assign_reg(block, node);
 666         }
 667
 668         /* assign instructions in the block */
 669         for (node = start; !sched_is_end(node); node = sched_next(node)) {
 670                 int arity = get_irn_arity(node);
 671                 int i;
 672
 673                 /* enforce use constraints */
 674                 enforce_constraints(&live_nodes, node);
 675
 676                 /* exchange values to copied values where needed */
 677                 for (i = 0; i < arity; ++i) {
 678                         ir_node      *op = get_irn_n(node, i);
 679                         assignment_t *assignment;
 680
 681                         if (!arch_irn_consider_in_reg_alloc(cls, op))
 682                                 continue;
 683                         assignment = get_current_assignment(op);
 684                         assert(assignment != NULL);
 685                         if (op != assignment->value) {
 686                                 set_irn_n(node, i, assignment->value);
 687                         }
 688                 }
 689
 690                 free_last_uses(&live_nodes, node);
 691
 692                 /* assign output registers */
 693                 /* TODO: 2 phases: first: pre-assigned ones, 2nd real regs */
 694                 if (get_irn_mode(node) == mode_T) {
 695                         const ir_edge_t *edge;
 696                         foreach_out_edge(node, edge) {
 697                                 ir_node *proj = get_edge_src_irn(edge);
 698                                 if (!arch_irn_consider_in_reg_alloc(cls, proj))
 699                                         continue;
 700                                 assign_reg(block, proj);
 701                         }
 702                 } else if (arch_irn_consider_in_reg_alloc(cls, node)) {
 703                         assign_reg(block, node);
 704                 }
 705         }
 706
 707         foreach_ir_nodeset(&live_nodes, node, iter) {
 708                 free_reg_of_value(node);
 709         }
 710
 711         ir_nodeset_destroy(&live_nodes);
 712 }
 713
 714 void be_straight_alloc_cls(void)
 715 {
 716         n_regs         = arch_register_class_n_regs(cls);
 717         lv             = be_assure_liveness(birg);
 718         be_liveness_assure_sets(lv);
 719         be_liveness_assure_chk(lv);
 720
 721         assignments = obstack_alloc(&obst, n_regs * sizeof(assignments[0]));
 722
 723         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK | IR_RESOURCE_IRN_VISITED);
 724         inc_irg_visited(irg);
 725
 726         irg_block_walk_graph(irg, analyze_block, NULL, NULL);
 727         irg_block_walk_graph(irg, allocate_coalesce_block, NULL, NULL);
 728
 729         ir_free_resources(irg, IR_RESOURCE_IRN_LINK | IR_RESOURCE_IRN_VISITED);
 730 }
 731
 732 static void spill(void)
 733 {
 734         /* TODO: rewrite pre_spill_prepare to work without chordal_env... */
 735         be_chordal_env_t  cenv;
 736         memset(&cenv, 0, sizeof(cenv));
 737         cenv.obst          = &obst;
 738         cenv.irg           = irg;
 739         cenv.birg          = birg;
 740         cenv.cls           = cls;
 741         cenv.ignore_colors = ignore_regs;
 742
 743         /* make sure all nodes show their real register pressure */
 744         be_pre_spill_prepare_constr(&cenv);
 745
 746         /* spill */
 747         be_do_spill(birg, cls);
 748
 749         check_for_memory_operands(irg);
 750 }
 751
 752 static void be_straight_alloc(be_irg_t *new_birg)
 753 {
 754         const arch_env_t *arch_env = new_birg->main_env->arch_env;
 755         int   n_cls                = arch_env_get_n_reg_class(arch_env);
 756         int   c;
 757
 758         obstack_init(&obst);
 759
 760         birg      = new_birg;
 761         irg       = be_get_birg_irg(birg);
 762         execfreqs = birg->exec_freq;
 763
 764         /* TODO: extract some of the stuff from bechordal allocator, like
 765          * statistics, time measurements, etc. and use them here too */
 766
 767         for (c = 0; c < n_cls; ++c) {
 768                 cls = arch_env_get_reg_class(arch_env, c);
 769                 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
 770                         continue;
 771
 772                 stat_ev_ctx_push_str("bestraight_cls", cls->name);
 773
 774                 n_regs      = cls->n_regs;
 775                 ignore_regs = bitset_malloc(n_regs);
 776                 be_put_ignore_regs(birg, cls, ignore_regs);
 777
 778                 spill();
 779
 780                 /* verify schedule and register pressure */
 781                 BE_TIMER_PUSH(t_verify);
 782                 if (birg->main_env->options->vrfy_option == BE_CH_VRFY_WARN) {
 783                         be_verify_schedule(birg);
 784                         be_verify_register_pressure(birg, cls, irg);
 785                 } else if (birg->main_env->options->vrfy_option == BE_CH_VRFY_ASSERT) {
 786                         assert(be_verify_schedule(birg) && "Schedule verification failed");
 787                         assert(be_verify_register_pressure(birg, cls, irg)
 788                                 && "Register pressure verification failed");
 789                 }
 790                 BE_TIMER_POP(t_verify);
 791
 792                 BE_TIMER_PUSH(t_ra_color);
 793                 be_straight_alloc_cls();
 794                 BE_TIMER_POP(t_ra_color);
 795
 796                 bitset_free(ignore_regs);
 797
 798                 /* TODO: dump intermediate results */
 799
 800                 stat_ev_ctx_pop("bestraight_cls");
 801         }
 802
 803         obstack_free(&obst, NULL);
 804 }
 805
 806 static be_ra_t be_ra_straight = {
 807         be_straight_alloc,
 808 };
 809
 810 void be_init_straight_alloc(void)
 811 {
 812         FIRM_DBG_REGISTER(dbg, "firm.be.straightalloc");
 813
 814         be_register_allocator("straight", &be_ra_straight);
 815 }
 816
 817 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_straight_alloc);