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 "preferred" registers for live-ranges. This
  33  *    calculates for each register and each live-range a value indicating
  34  *    the usefulness. (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. Preferring 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         ir_node                   *in_node;
 346         unsigned                  i;
 347
 348         assert(arch_irn_consider_in_reg_alloc(cls, node));
 349
 350         /* preassigned register? */
 351         reg = arch_get_irn_register(node);
 352         if (reg != NULL) {
 353                 DB((dbg, LEVEL_2, "Preassignment %+F -> %s\n", node, reg->name));
 354                 use_reg(node, reg);
 355                 return;
 356         }
 357
 358         /* give should_be_same boni */
 359         info = get_allocation_info(node);
 360         req  = arch_get_register_req_out(node);
 361
 362         in_node = skip_Proj(node);
 363         if (req->type & arch_register_req_type_should_be_same) {
 364                 float weight = get_block_execfreq(execfreqs, block);
 365                 int   arity  = get_irn_arity(in_node);
 366                 int   i;
 367
 368                 assert(arity <= (int) sizeof(req->other_same) * 8);
 369                 for (i = 0; i < arity; ++i) {
 370                         ir_node               *in;
 371                         const arch_register_t *reg;
 372                         unsigned               r;
 373                         if (!rbitset_is_set(&req->other_same, i))
 374                                 continue;
 375
 376                         in  = get_irn_n(in_node, i);
 377                         reg = arch_get_irn_register(in);
 378                         assert(reg != NULL);
 379                         r = arch_register_get_index(reg);
 380                         if (bitset_is_set(ignore_regs, r))
 381                                 continue;
 382                         info->prefs[r] += weight * SHOULD_BE_SAME;
 383                 }
 384         }
 385
 386         /* TODO: handle must_be_different */
 387
 388         /*  */
 389         DB((dbg, LEVEL_2, "Candidates for %+F:", node));
 390         reg_prefs = alloca(n_regs * sizeof(reg_prefs[0]));
 391         fill_sort_candidates(reg_prefs, info);
 392         for (i = 0; i < n_regs; ++i) {
 393                 unsigned               num = reg_prefs[i].num;
 394                 const arch_register_t *reg = arch_register_for_index(cls, num);
 395                 DB((dbg, LEVEL_2, " %s(%f)", reg->name, reg_prefs[i].pref));
 396         }
 397         DB((dbg, LEVEL_2, "\n"));
 398
 399         for (i = 0; i < n_regs; ++i) {
 400                 unsigned r = reg_prefs[i].num;
 401                 /* ignores should be last and we should have a non-ignore left */
 402                 assert(!bitset_is_set(ignore_regs, r));
 403                 /* already used? TODO: It might be better to copy the value occupying the register around here, find out when... */
 404                 if (assignments[r].value != NULL)
 405                         continue;
 406                 use_reg(node, arch_register_for_index(cls, r));
 407                 break;
 408         }
 409 }
 410
 411 static void free_reg_of_value(ir_node *node)
 412 {
 413         allocation_info_t *info;
 414         assignment_t      *assignment;
 415         unsigned          r;
 416
 417         if (!arch_irn_consider_in_reg_alloc(cls, node))
 418                 return;
 419
 420         info       = get_allocation_info(node);
 421         assignment = info->current_assignment;
 422
 423         assert(assignment != NULL);
 424
 425         r = assignment - assignments;
 426         DB((dbg, LEVEL_2, "Value %+F ended, freeing %s\n",
 427                 node, arch_register_for_index(cls, r)->name));
 428         assignment->value        = NULL;
 429         info->current_assignment = NULL;
 430 }
 431
 432 static unsigned get_current_reg(ir_node *node)
 433 {
 434         allocation_info_t *info       = get_allocation_info(node);
 435         assignment_t      *assignment = info->current_assignment;
 436         return assignment - assignments;
 437 }
 438
 439 static assignment_t *get_current_assignment(ir_node *node)
 440 {
 441         allocation_info_t *info = get_allocation_info(node);
 442         return info->current_assignment;
 443 }
 444
 445 static void permutate_values(ir_nodeset_t *live_nodes, ir_node *before,
 446                              unsigned *permutation)
 447 {
 448         ir_node *block, *perm;
 449         ir_node **in = ALLOCAN(ir_node*, n_regs);
 450         size_t    r;
 451
 452         int i = 0;
 453         for (r = 0; r < n_regs; ++r) {
 454                 unsigned     new_reg = permutation[r];
 455                 assignment_t *assignment;
 456                 ir_node      *value;
 457
 458                 if (new_reg == r)
 459                         continue;
 460
 461                 assignment = &assignments[r];
 462                 value      = assignment->value;
 463                 if (value == NULL) {
 464                         /* nothing to do here, reg is not live */
 465                         permutation[r] = r;
 466                         continue;
 467                 }
 468
 469                 in[i++] = value;
 470
 471                 free_reg_of_value(value);
 472                 ir_nodeset_remove(live_nodes, value);
 473         }
 474
 475         block = get_nodes_block(before);
 476         perm  = be_new_Perm(cls, irg, block, i, in);
 477
 478         sched_add_before(before, perm);
 479
 480         i = 0;
 481         for (r = 0; r < n_regs; ++r) {
 482                 unsigned new_reg = permutation[r];
 483                 ir_node  *value;
 484                 ir_mode  *mode;
 485                 ir_node  *proj;
 486                 const arch_register_t *reg;
 487
 488                 if (new_reg == r)
 489                         continue;
 490
 491                 value = in[i];
 492                 mode  = get_irn_mode(value);
 493                 proj  = new_r_Proj(irg, block, perm, mode, i);
 494
 495                 reg = arch_register_for_index(cls, new_reg);
 496
 497                 link_to(proj, value);
 498                 use_reg(proj, reg);
 499                 ir_nodeset_insert(live_nodes, proj);
 500
 501                 ++i;
 502         }
 503 }
 504
 505 /* free regs for values last used */
 506 static void free_last_uses(ir_nodeset_t *live_nodes, ir_node *node)
 507 {
 508         allocation_info_t *info  = get_allocation_info(node);
 509         int                arity = get_irn_arity(node);
 510         int                i;
 511         for (i = 0; i < arity; ++i) {
 512                 ir_node *op;
 513
 514                 if (!rbitset_is_set(&info->last_uses, i))
 515                         continue;
 516
 517                 op = get_irn_n(node, i);
 518                 free_reg_of_value(op);
 519                 ir_nodeset_remove(live_nodes, op);
 520         }
 521 }
 522
 523 static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node)
 524 {
 525         int arity = get_irn_arity(node);
 526         int i, dummy, res;
 527         hungarian_problem_t *bp;
 528         unsigned l, r, p;
 529         unsigned *assignment;
 530
 531         /* see if any use constraints are not met */
 532         bool good = true;
 533         for (i = 0; i < arity; ++i) {
 534                 ir_node                   *op = get_irn_n(node, i);
 535                 const arch_register_req_t *req;
 536                 const unsigned            *limited;
 537                 unsigned                  r;
 538
 539                 if (!arch_irn_consider_in_reg_alloc(cls, op))
 540                         continue;
 541
 542                 req = arch_get_register_req(node, i);
 543                 if ((req->type & arch_register_req_type_limited) == 0)
 544                         continue;
 545
 546                 limited = req->limited;
 547                 r       = get_current_reg(op);
 548                 if (!rbitset_is_set(limited, r)) {
 549                         good = false;
 550                         break;
 551                 }
 552         }
 553
 554         if (good)
 555                 return;
 556
 557         /* swap values around */
 558         bp = hungarian_new(n_regs, n_regs, HUNGARIAN_MATCH_PERFECT);
 559
 560         /* add all combinations, then remove not allowed ones */
 561         for (l = 0; l < n_regs; ++l) {
 562                 if (bitset_is_set(ignore_regs, l)) {
 563                         hungarian_add(bp, l, l, 90);
 564                         continue;
 565                 }
 566
 567                 for (r = 0; r < n_regs; ++r) {
 568                         if (bitset_is_set(ignore_regs, r))
 569                                 continue;
 570
 571                         hungarian_add(bp, l, r, l == r ? 90 : 89);
 572                 }
 573         }
 574
 575         for (i = 0; i < arity; ++i) {
 576                 ir_node                   *op = get_irn_n(node, i);
 577                 const arch_register_req_t *req;
 578                 const unsigned            *limited;
 579                 unsigned                  current_reg;
 580
 581                 if (!arch_irn_consider_in_reg_alloc(cls, op))
 582                         continue;
 583
 584                 req = arch_get_register_req(node, i);
 585                 if ((req->type & arch_register_req_type_limited) == 0)
 586                         continue;
 587
 588                 limited     = req->limited;
 589                 current_reg = get_current_reg(op);
 590                 for (r = 0; r < n_regs; ++r) {
 591                         if (rbitset_is_set(limited, r))
 592                                 continue;
 593                         hungarian_remv(bp, current_reg, r);
 594                 }
 595         }
 596
 597         hungarian_print_costmatrix(bp, 1);
 598         hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
 599
 600         assignment = ALLOCAN(unsigned, n_regs);
 601         res = hungarian_solve(bp, (int*) assignment, &dummy, 0);
 602         assert(res == 0);
 603
 604         printf("Swap result:");
 605         for (p = 0; p < n_regs; ++p) {
 606                 printf(" %d", assignment[p]);
 607         }
 608         printf("\n");
 609
 610         hungarian_free(bp);
 611
 612         permutate_values(live_nodes, node, assignment);
 613 }
 614
 615 static void allocate_coalesce_block(ir_node *block, void *data)
 616 {
 617         int                   i;
 618         ir_nodeset_t          live_nodes;
 619         ir_nodeset_iterator_t iter;
 620         ir_node               *node, *start;
 621
 622         /* clear assignments */
 623         memset(assignments, 0, n_regs * sizeof(assignments[0]));
 624
 625         (void) data;
 626
 627         /* collect live-in nodes and preassigned values */
 628         ir_nodeset_init(&live_nodes);
 629         be_lv_foreach(lv, block, be_lv_state_in, i) {
 630                 const arch_register_t *reg;
 631
 632                 node = be_lv_get_irn(lv, block, i);
 633                 if (!arch_irn_consider_in_reg_alloc(cls, node))
 634                         continue;
 635
 636                 ir_nodeset_insert(&live_nodes, node);
 637
 638                 /* fill in regs already assigned */
 639                 reg = arch_get_irn_register(node);
 640                 if (reg != NULL) {
 641                         use_reg(node, reg);
 642                 }
 643         }
 644
 645         /* handle phis... */
 646         node = sched_first(block);
 647         for ( ; is_Phi(node); node = sched_next(node)) {
 648                 const arch_register_t *reg;
 649
 650                 if (!arch_irn_consider_in_reg_alloc(cls, node))
 651                         continue;
 652
 653                 /* fill in regs already assigned */
 654                 reg = arch_get_irn_register(node);
 655                 if (reg != NULL) {
 656                         use_reg(node, reg);
 657                 } else {
 658                         /* TODO: give boni for registers already assigned at the
 659                            predecessors */
 660                 }
 661         }
 662         start = node;
 663
 664         /* assign regs for live-in values */
 665         foreach_ir_nodeset(&live_nodes, node, iter) {
 666                 assign_reg(block, node);
 667         }
 668
 669         /* assign instructions in the block */
 670         for (node = start; !sched_is_end(node); node = sched_next(node)) {
 671                 int arity = get_irn_arity(node);
 672                 int i;
 673
 674                 /* enforce use constraints */
 675                 enforce_constraints(&live_nodes, node);
 676
 677                 /* exchange values to copied values where needed */
 678                 for (i = 0; i < arity; ++i) {
 679                         ir_node      *op = get_irn_n(node, i);
 680                         assignment_t *assignment;
 681
 682                         if (!arch_irn_consider_in_reg_alloc(cls, op))
 683                                 continue;
 684                         assignment = get_current_assignment(op);
 685                         assert(assignment != NULL);
 686                         if (op != assignment->value) {
 687                                 set_irn_n(node, i, assignment->value);
 688                         }
 689                 }
 690
 691                 free_last_uses(&live_nodes, node);
 692
 693                 /* assign output registers */
 694                 /* TODO: 2 phases: first: pre-assigned ones, 2nd real regs */
 695                 if (get_irn_mode(node) == mode_T) {
 696                         const ir_edge_t *edge;
 697                         foreach_out_edge(node, edge) {
 698                                 ir_node *proj = get_edge_src_irn(edge);
 699                                 if (!arch_irn_consider_in_reg_alloc(cls, proj))
 700                                         continue;
 701                                 assign_reg(block, proj);
 702                         }
 703                 } else if (arch_irn_consider_in_reg_alloc(cls, node)) {
 704                         assign_reg(block, node);
 705                 }
 706         }
 707
 708         foreach_ir_nodeset(&live_nodes, node, iter) {
 709                 free_reg_of_value(node);
 710         }
 711
 712         ir_nodeset_destroy(&live_nodes);
 713 }
 714
 715 void be_straight_alloc_cls(void)
 716 {
 717         n_regs         = arch_register_class_n_regs(cls);
 718         lv             = be_assure_liveness(birg);
 719         be_liveness_assure_sets(lv);
 720         be_liveness_assure_chk(lv);
 721
 722         assignments = obstack_alloc(&obst, n_regs * sizeof(assignments[0]));
 723
 724         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK | IR_RESOURCE_IRN_VISITED);
 725         inc_irg_visited(irg);
 726
 727         irg_block_walk_graph(irg, analyze_block, NULL, NULL);
 728         irg_block_walk_graph(irg, allocate_coalesce_block, NULL, NULL);
 729
 730         ir_free_resources(irg, IR_RESOURCE_IRN_LINK | IR_RESOURCE_IRN_VISITED);
 731 }
 732
 733 static void spill(void)
 734 {
 735         /* TODO: rewrite pre_spill_prepare to work without chordal_env... */
 736         be_chordal_env_t  cenv;
 737         memset(&cenv, 0, sizeof(cenv));
 738         cenv.obst          = &obst;
 739         cenv.irg           = irg;
 740         cenv.birg          = birg;
 741         cenv.cls           = cls;
 742         cenv.ignore_colors = ignore_regs;
 743
 744         /* make sure all nodes show their real register pressure */
 745         be_pre_spill_prepare_constr(&cenv);
 746
 747         /* spill */
 748         be_do_spill(birg, cls);
 749
 750         check_for_memory_operands(irg);
 751 }
 752
 753 static void be_straight_alloc(be_irg_t *new_birg)
 754 {
 755         const arch_env_t *arch_env = new_birg->main_env->arch_env;
 756         int   n_cls                = arch_env_get_n_reg_class(arch_env);
 757         int   c;
 758
 759         obstack_init(&obst);
 760
 761         birg      = new_birg;
 762         irg       = be_get_birg_irg(birg);
 763         execfreqs = birg->exec_freq;
 764
 765         /* TODO: extract some of the stuff from bechordal allocator, like
 766          * statistics, time measurements, etc. and use them here too */
 767
 768         for (c = 0; c < n_cls; ++c) {
 769                 cls = arch_env_get_reg_class(arch_env, c);
 770                 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
 771                         continue;
 772
 773                 stat_ev_ctx_push_str("bestraight_cls", cls->name);
 774
 775                 n_regs      = cls->n_regs;
 776                 ignore_regs = bitset_malloc(n_regs);
 777                 be_put_ignore_regs(birg, cls, ignore_regs);
 778
 779                 spill();
 780
 781                 /* verify schedule and register pressure */
 782                 BE_TIMER_PUSH(t_verify);
 783                 if (birg->main_env->options->vrfy_option == BE_CH_VRFY_WARN) {
 784                         be_verify_schedule(birg);
 785                         be_verify_register_pressure(birg, cls, irg);
 786                 } else if (birg->main_env->options->vrfy_option == BE_CH_VRFY_ASSERT) {
 787                         assert(be_verify_schedule(birg) && "Schedule verification failed");
 788                         assert(be_verify_register_pressure(birg, cls, irg)
 789                                 && "Register pressure verification failed");
 790                 }
 791                 BE_TIMER_POP(t_verify);
 792
 793                 BE_TIMER_PUSH(t_ra_color);
 794                 be_straight_alloc_cls();
 795                 BE_TIMER_POP(t_ra_color);
 796
 797                 bitset_free(ignore_regs);
 798
 799                 /* TODO: dump intermediate results */
 800
 801                 stat_ev_ctx_pop("bestraight_cls");
 802         }
 803
 804         obstack_free(&obst, NULL);
 805 }
 806
 807 static be_ra_t be_ra_straight = {
 808         be_straight_alloc,
 809 };
 810
 811 void be_init_straight_alloc(void)
 812 {
 813         FIRM_DBG_REGISTER(dbg, "firm.be.straightalloc");
 814
 815         be_register_allocator("straight", &be_ra_straight);
 816 }
 817
 818 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_straight_alloc);