nsz Git - libfirm/blob - ir/be/becopyilp2.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       ILP based copy minimization.
  23  * @author      Daniel Grund
  24  * @date        28.02.2006
  25  *
  26  * ILP formalization using G=(V, E, Q):
  27  *  - 2 class of variables: coloring vars x_ic   and   equal color vars y_ij
  28  *  - Path constraints
  29  *  - Clique-star constraints
  30  *
  31  *
  32  * \min \sum_{ (i,j) \in Q }  w_ij y_ij
  33  *
  34  *     \sum_c x_nc           =  1           n \in N, c \in C
  35  *
  36  *     x_nc                  =  0           n \in N, c \not\in C(n)
  37  *
  38  *     \sum x_nc            <=  1           x_nc \in Clique \in AllCliques,  c \in C
  39  *
  40  *     \sum_{e \in p} y_e   >=  1           p \in P      path constraints
  41  *
  42  *     \sum_{e \in cs} y_e  >= |cs| - 1     cs \in CP    clique-star constraints
  43  *
  44  *     x_nc, y_ij \in N,   w_ij \in R^+
  45  */
  46 #include "config.h"
  47
  48 #include "be_t.h"
  49 #include "bitset.h"
  50 #include "error.h"
  51 #include "raw_bitset.h"
  52 #include "pdeq.h"
  53
  54 #include "util.h"
  55 #include "irgwalk.h"
  56 #include "becopyilp_t.h"
  57 #include "beifg.h"
  58 #include "besched.h"
  59 #include "bemodule.h"
  60
  61 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
  62
  63 typedef struct local_env_t {
  64         int             first_x_var;
  65         int             last_x_var;
  66         const unsigned *allocatable_colors;
  67 } local_env_t;
  68
  69 static unsigned check_alignment_constraints(ir_node *node)
  70 {
  71         const arch_register_req_t *req = arch_get_irn_register_req(node);
  72         // For larger than 1 variables, support only aligned constraints
  73         assert((arch_register_req_is(req, aligned) || req->width == 1) && "Unaligned large (width > 1) variables not supported");
  74         return arch_register_req_is(req, aligned) && req->width > 1;
  75 }
  76
  77 static void make_color_var_name(char *buf, size_t buf_size,
  78                                 const ir_node *node, unsigned color)
  79 {
  80         unsigned node_idx = get_irn_idx(node);
  81         snprintf(buf, buf_size, "x_%u_%u", node_idx, color);
  82 }
  83
  84 static void build_coloring_cstr(ilp_env_t *ienv)
  85 {
  86         local_env_t    *lenv   = (local_env_t*)ienv->env;
  87         be_ifg_t       *ifg    = ienv->co->cenv->ifg;
  88         unsigned        n_regs = arch_register_class_n_regs(ienv->co->cls);
  89         const unsigned *allocatable_colors = lenv->allocatable_colors;
  90         nodes_iter_t    iter;
  91         char            buf[32];
  92
  93         unsigned *const colors = rbitset_alloca(n_regs);
  94         be_ifg_foreach_node(ifg, &iter, irn) {
  95                 const arch_register_req_t *req;
  96                 unsigned                   col;
  97                 int                        cst_idx;
  98                 unsigned                   curr_node_color;
  99                 unsigned                   has_alignment_cstr;
 100
 101                 if (sr_is_removed(ienv->sr, irn))
 102                         continue;
 103
 104                 has_alignment_cstr = check_alignment_constraints(irn);
 105
 106                 req = arch_get_irn_register_req(irn);
 107
 108                 /* get assignable colors */
 109                 if (arch_register_req_is(req, limited)) {
 110                         rbitset_copy(colors, req->limited, n_regs);
 111                 } else {
 112                         rbitset_copy(colors, allocatable_colors, n_regs);
 113                 }
 114
 115                 /* add the coloring constraint */
 116                 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 1.0);
 117
 118                 curr_node_color = get_irn_col(irn);
 119                 for (col = 0; col < n_regs; ++col) {
 120                         int    var_idx;
 121                         double val;
 122                         if (!rbitset_is_set(colors, col)
 123                                 || (has_alignment_cstr && ((col % req->width) != 0)))
 124                                 continue;
 125
 126                         make_color_var_name(buf, sizeof(buf), irn, col);
 127                         var_idx = lpp_add_var(ienv->lp, buf, lpp_binary, 0.0);
 128                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
 129
 130                         val = (col == curr_node_color) ? 1.0 : 0.0;
 131                         lpp_set_start_value(ienv->lp, var_idx, val);
 132
 133                         lenv->last_x_var = var_idx;
 134                         if (lenv->first_x_var == -1)
 135                                 lenv->first_x_var = var_idx;
 136                 }
 137
 138                 /* add register constraint constraints */
 139                 for (col = 0; col < n_regs; ++col) {
 140                         int cst_idx;
 141                         int var_idx;
 142                         if (rbitset_is_set(colors, col)
 143                                 // for aligned variable, we set the unaligned part to 0
 144                                 && (!has_alignment_cstr || ((col % req->width) == 0)))
 145                                 continue;
 146
 147                         make_color_var_name(buf, sizeof(buf), irn, col);
 148                         cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 0.0);
 149                         var_idx = lpp_add_var(ienv->lp, buf, lpp_binary, 0.0);
 150                         lpp_set_start_value(ienv->lp, var_idx, 0.0);
 151                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
 152
 153                         lenv->last_x_var = var_idx;
 154                 }
 155         }
 156 }
 157
 158 static void build_interference_cstr(ilp_env_t *ienv)
 159 {
 160         lpp_t          *lpp      = ienv->lp;
 161         local_env_t    *lenv     = (local_env_t*)ienv->env;
 162         be_ifg_t       *ifg      = ienv->co->cenv->ifg;
 163         unsigned        n_colors = arch_register_class_n_regs(ienv->co->cls);
 164         ir_node       **clique   = ALLOCAN(ir_node*, n_colors);
 165         const unsigned *allocatable_colors = lenv->allocatable_colors;
 166         cliques_iter_t iter;
 167         int            size;
 168         unsigned       col;
 169         int            i;
 170
 171         /* for each maximal clique */
 172         be_ifg_foreach_clique(ifg, &iter, clique, &size) {
 173                 unsigned realsize = 0;
 174
 175                 for (i=0; i<size; ++i) {
 176                         if (!sr_is_removed(ienv->sr, clique[i]))
 177                                 ++realsize;
 178                 }
 179
 180                 if (realsize < 2)
 181                         continue;
 182
 183                 /* for all colors */
 184                 for (col=0; col<n_colors; ++col) {
 185                         int cst_idx;
 186                         if (!rbitset_is_set(allocatable_colors, col))
 187                                 continue;
 188
 189                         cst_idx = lpp_add_cst(lpp, NULL, lpp_less_equal, 1.0);
 190
 191                         /* for each member of this clique */
 192                         for (i=0; i<size; ++i) {
 193                                 ir_node *irn = clique[i];
 194                                 char     buf[32];
 195                                 int      var_idx;
 196                                 unsigned aligment_offset = 0;
 197
 198                                 if (sr_is_removed(ienv->sr, irn))
 199                                         continue;
 200
 201                                 // Use the first part of the large registers for all
 202                                 // interference, since it is the only colorable one.
 203                                 if (check_alignment_constraints(irn)) {
 204                                         const arch_register_req_t *req
 205                                                 = arch_get_irn_register_req(irn);
 206                                         aligment_offset = col % req->width;
 207                                 }
 208
 209                                 make_color_var_name(buf, sizeof(buf), irn,
 210                                                                         col - aligment_offset);
 211                                 var_idx = lpp_get_var_idx(lpp, buf);
 212                                 lpp_set_factor_fast(lpp, cst_idx, var_idx, 1);
 213                         }
 214                 }
 215         }
 216 }
 217
 218 static void make_affinity_var_name(char *buf, size_t buf_size,
 219                                    const ir_node *node1, const ir_node *node2)
 220 {
 221         unsigned n1 = get_irn_idx(node1);
 222         unsigned n2 = get_irn_idx(node2);
 223         if (n1 < n2) {
 224                 snprintf(buf, buf_size, "y_%u_%u", n1, n2);
 225         } else {
 226                 snprintf(buf, buf_size, "y_%u_%u", n2, n1);
 227         }
 228 }
 229
 230
 231 /**
 232  * TODO: Remove the dependency of the opt-units data structure
 233  *       by walking over all affinity edges. Graph structure
 234  *       does not provide this walker, yet.
 235  */
 236 static void build_affinity_cstr(ilp_env_t *ienv)
 237 {
 238         unsigned  n_colors = arch_register_class_n_regs(ienv->co->cls);
 239
 240         /* for all optimization units */
 241         list_for_each_entry(unit_t, curr, &ienv->co->units, units) {
 242                 ir_node *root     = curr->nodes[0];
 243                 unsigned root_col = get_irn_col(root);
 244                 int      i;
 245
 246                 for (i = 1; i < curr->node_count; ++i) {
 247                         ir_node *arg     = curr->nodes[i];
 248                         unsigned arg_col = get_irn_col(arg);
 249                         double   val;
 250                         char     buf[32];
 251                         unsigned col;
 252                         int      y_idx;
 253
 254                         /* add a new affinity variable */
 255                         make_affinity_var_name(buf, sizeof(buf), arg, root);
 256                         y_idx = lpp_add_var(ienv->lp, buf, lpp_binary, curr->costs[i]);
 257                         val   = (root_col == arg_col) ? 0.0 : 1.0;
 258                         lpp_set_start_value(ienv->lp, y_idx, val);
 259
 260                         /* add constraints relating the affinity var to the color vars */
 261                         for (col=0; col<n_colors; ++col) {
 262                                 int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_less_equal, 0.0);
 263                                 int root_idx;
 264                                 int arg_idx;
 265
 266                                 make_color_var_name(buf, sizeof(buf), root, col);
 267                                 root_idx = lpp_get_var_idx(ienv->lp, buf);
 268                                 make_color_var_name(buf, sizeof(buf), arg, col);
 269                                 arg_idx  = lpp_get_var_idx(ienv->lp, buf);
 270
 271                                 lpp_set_factor_fast(ienv->lp, cst_idx, root_idx,  1.0);
 272                                 lpp_set_factor_fast(ienv->lp, cst_idx, arg_idx,  -1.0);
 273                                 lpp_set_factor_fast(ienv->lp, cst_idx, y_idx, -1.0);
 274                         }
 275                 }
 276         }
 277 }
 278
 279 /**
 280  * Helping stuff for build_clique_star_cstr
 281  */
 282 typedef struct edge_t {
 283         ir_node *n1;
 284         ir_node *n2;
 285 } edge_t;
 286
 287 static int compare_edge_t(const void *k1, const void *k2, size_t size)
 288 {
 289         const edge_t *e1 = (const edge_t*)k1;
 290         const edge_t *e2 = (const edge_t*)k2;
 291         (void) size;
 292
 293         return ! (e1->n1 == e2->n1 && e1->n2 == e2->n2);
 294 }
 295
 296 #define HASH_EDGE(e) (hash_irn((e)->n1) ^ hash_irn((e)->n2))
 297
 298 static inline edge_t *add_edge(set *edges, ir_node *n1, ir_node *n2, size_t *counter)
 299 {
 300         edge_t new_edge;
 301
 302         if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
 303                 new_edge.n1 = n1;
 304                 new_edge.n2 = n2;
 305         } else {
 306                 new_edge.n1 = n2;
 307                 new_edge.n2 = n1;
 308         }
 309         (*counter)++;
 310         return set_insert(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 311 }
 312
 313 static inline edge_t *find_edge(set *edges, ir_node *n1, ir_node *n2)
 314 {
 315         edge_t new_edge;
 316
 317         if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
 318                 new_edge.n1 = n1;
 319                 new_edge.n2 = n2;
 320         } else {
 321                 new_edge.n1 = n2;
 322                 new_edge.n2 = n1;
 323         }
 324         return set_find(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 325 }
 326
 327 static inline void remove_edge(set *edges, ir_node *n1, ir_node *n2, size_t *counter)
 328 {
 329         edge_t new_edge, *e;
 330
 331         if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
 332                 new_edge.n1 = n1;
 333                 new_edge.n2 = n2;
 334         } else {
 335                 new_edge.n1 = n2;
 336                 new_edge.n2 = n1;
 337         }
 338         e = set_find(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 339         if (e) {
 340                 e->n1 = NULL;
 341                 e->n2 = NULL;
 342                 (*counter)--;
 343         }
 344 }
 345
 346 #define pset_foreach(pset, irn) foreach_pset((pset), ir_node, (irn))
 347
 348 /**
 349  * Search for an interference clique and an external node
 350  * with affinity edges to all nodes of the clique.
 351  * At most 1 node of the clique can be colored equally with the external node.
 352  */
 353 static void build_clique_star_cstr(ilp_env_t *ienv)
 354 {
 355         /* for each node with affinity edges */
 356         co_gs_foreach_aff_node(ienv->co, aff) {
 357                 struct obstack ob;
 358                 const ir_node *center = aff->irn;
 359                 ir_node **nodes;
 360                 set *edges;
 361                 int i, o, n_nodes;
 362                 size_t n_edges;
 363
 364                 if (arch_irn_is_ignore(aff->irn))
 365                         continue;
 366
 367                 obstack_init(&ob);
 368                 edges = new_set(compare_edge_t, 8);
 369
 370                 /* get all affinity neighbours */
 371                 n_nodes = 0;
 372                 co_gs_foreach_neighb(aff, nbr) {
 373                         if (!arch_irn_is_ignore(nbr->irn)) {
 374                                 obstack_ptr_grow(&ob, nbr->irn);
 375                                 ++n_nodes;
 376                         }
 377                 }
 378                 nodes = (ir_node**)obstack_finish(&ob);
 379
 380                 /* get all interference edges between these */
 381                 n_edges = 0;
 382                 for (i=0; i<n_nodes; ++i) {
 383                         for (o=0; o<i; ++o) {
 384                                 if (be_ifg_connected(ienv->co->cenv->ifg, nodes[i], nodes[o]))
 385                                         add_edge(edges, nodes[i], nodes[o], &n_edges);
 386                         }
 387                 }
 388
 389                 /* cover all these interference edges with maximal cliques */
 390                 while (n_edges) {
 391                         edge_t *e;
 392                         pset   *clique = pset_new_ptr(8);
 393                         bool    growed;
 394
 395                         /* get 2 starting nodes to form a clique */
 396                         for (e = set_first(edge_t, edges); !e->n1; e = set_next(edge_t, edges)) {}
 397
 398                         /* we could be stepped out of the loop before the set iterated to the end */
 399                         set_break(edges);
 400
 401                         pset_insert_ptr(clique, e->n1);
 402                         pset_insert_ptr(clique, e->n2);
 403                         remove_edge(edges, e->n1, e->n2, &n_edges);
 404
 405                         /* while the clique is growing */
 406                         do {
 407                                 growed = false;
 408
 409                                 /* search for a candidate to extend the clique */
 410                                 for (i=0; i<n_nodes; ++i) {
 411                                         ir_node *cand = nodes[i];
 412                                         bool     is_cand;
 413
 414                                         /* if its already in the clique try the next */
 415                                         if (pset_find_ptr(clique, cand))
 416                                                 continue;
 417
 418                                         /* are there all necessary interferences? */
 419                                         is_cand = true;
 420                                         pset_foreach(clique, member) {
 421                                                 if (!find_edge(edges, cand, member)) {
 422                                                         is_cand = false;
 423                                                         pset_break(clique);
 424                                                         break;
 425                                                 }
 426                                         }
 427
 428                                         /* now we know if we have a clique extender */
 429                                         if (is_cand) {
 430                                                 /* first remove all covered edges */
 431                                                 pset_foreach(clique, member)
 432                                                         remove_edge(edges, cand, member, &n_edges);
 433
 434                                                 /* insert into clique */
 435                                                 pset_insert_ptr(clique, cand);
 436                                                 growed = true;
 437                                                 break;
 438                                         }
 439                                 }
 440                         } while (growed);
 441
 442                         /* now the clique is maximal. Finally add the constraint */
 443                         {
 444                                 int  var_idx;
 445                                 int  cst_idx;
 446                                 char buf[32];
 447
 448                                 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater_equal, pset_count(clique)-1);
 449
 450                                 pset_foreach(clique, member) {
 451                                         make_affinity_var_name(buf, sizeof(buf), center, member);
 452                                         var_idx = lpp_get_var_idx(ienv->lp, buf);
 453                                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
 454                                 }
 455                         }
 456
 457                         del_pset(clique);
 458                 }
 459
 460                 del_set(edges);
 461                 obstack_free(&ob, NULL);
 462         }
 463 }
 464
 465 static void extend_path(ilp_env_t *ienv, pdeq *path, const ir_node *irn)
 466 {
 467         be_ifg_t *ifg = ienv->co->cenv->ifg;
 468         int i, len;
 469         ir_node **curr_path;
 470         affinity_node_t *aff;
 471
 472         /* do not walk backwards or in circles */
 473         if (pdeq_contains(path, irn))
 474                 return;
 475
 476         if (arch_irn_is_ignore(irn))
 477                 return;
 478
 479         /* insert the new irn */
 480         pdeq_putr(path, irn);
 481
 482         /* check for forbidden interferences */
 483         len       = pdeq_len(path);
 484         curr_path = ALLOCAN(ir_node*, len);
 485         pdeq_copyl(path, (const void **)curr_path);
 486
 487         for (i=1; i<len; ++i) {
 488                 if (be_ifg_connected(ifg, irn, curr_path[i]))
 489                         goto end;
 490         }
 491
 492         /* check for terminating interference */
 493         if (be_ifg_connected(ifg, irn, curr_path[0])) {
 494                 /* One node is not a path. */
 495                 /* And a path of length 2 is covered by a clique star constraint. */
 496                 if (len > 2) {
 497                         /* finally build the constraint */
 498                         int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater_equal, 1.0);
 499                         for (i=1; i<len; ++i) {
 500                                 char buf[32];
 501                                 int  var_idx;
 502
 503                                 make_affinity_var_name(buf, sizeof(buf), curr_path[i-1], curr_path[i]);
 504                                 var_idx = lpp_get_var_idx(ienv->lp, buf);
 505                                 lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
 506                         }
 507                 }
 508
 509                 /* this path cannot be extended anymore */
 510                 goto end;
 511         }
 512
 513         /* recursively extend the path */
 514         aff = get_affinity_info(ienv->co, irn);
 515         co_gs_foreach_neighb(aff, nbr) {
 516                 extend_path(ienv, path, nbr->irn);
 517         }
 518
 519 end:
 520         /* remove the irn */
 521         pdeq_getr(path);
 522 }
 523
 524 /**
 525  * Search a path of affinity edges, whose ends are connected
 526  * by an interference edge and there are no other interference
 527  * edges in between.
 528  * Then at least one of these affinity edges must break.
 529  */
 530 static void build_path_cstr(ilp_env_t *ienv)
 531 {
 532         /* for each node with affinity edges */
 533         co_gs_foreach_aff_node(ienv->co, aff_info) {
 534                 pdeq *path = new_pdeq();
 535
 536                 extend_path(ienv, path, aff_info->irn);
 537
 538                 del_pdeq(path);
 539         }
 540 }
 541
 542 static void ilp2_build(ilp_env_t *ienv)
 543 {
 544         int lower_bound;
 545
 546         ienv->lp = lpp_new(ienv->co->name, lpp_minimize);
 547         build_coloring_cstr(ienv);
 548         build_interference_cstr(ienv);
 549         build_affinity_cstr(ienv);
 550         build_clique_star_cstr(ienv);
 551         build_path_cstr(ienv);
 552
 553         lower_bound = co_get_lower_bound(ienv->co) - co_get_inevit_copy_costs(ienv->co);
 554         lpp_set_bound(ienv->lp, lower_bound);
 555 }
 556
 557 static void ilp2_apply(ilp_env_t *ienv)
 558 {
 559         local_env_t *lenv = (local_env_t*)ienv->env;
 560         ir_graph    *irg  = ienv->co->irg;
 561
 562         /* first check if there was sth. to optimize */
 563         if (lenv->first_x_var >= 0) {
 564                 int              count = lenv->last_x_var - lenv->first_x_var + 1;
 565                 double          *sol   = XMALLOCN(double, count);
 566                 lpp_sol_state_t  state = lpp_get_solution(ienv->lp, sol, lenv->first_x_var, lenv->last_x_var);
 567                 int              i;
 568
 569                 if (state != lpp_optimal) {
 570                         printf("WARNING %s: Solution state is not 'optimal': %d\n",
 571                                ienv->co->name, (int)state);
 572                         if (state < lpp_feasible) {
 573                                 panic("Copy coalescing solution not feasible!");
 574                         }
 575                 }
 576
 577                 for (i=0; i<count; ++i) {
 578                         unsigned nodenr;
 579                         unsigned color;
 580                         char     var_name[32];
 581                         if (sol[i] <= 1-EPSILON)
 582                                 continue;
 583                         /* split variable name into components */
 584                         lpp_get_var_name(ienv->lp, lenv->first_x_var+i, var_name, sizeof(var_name));
 585
 586                         if (sscanf(var_name, "x_%u_%u", &nodenr, &color) == 2) {
 587                                 ir_node *irn = get_idx_irn(irg, nodenr);
 588                                 set_irn_col(ienv->co->cls, irn, color);
 589                         } else {
 590                                 panic("This should be a x-var");
 591                         }
 592                 }
 593
 594                 xfree(sol);
 595         }
 596
 597 #ifdef COPYOPT_STAT
 598         /* TODO adapt to multiple possible ILPs */
 599         copystat_add_ilp_time((int)(1000.0*lpp_get_sol_time(pi->curr_lp)));  //now we have ms
 600         copystat_add_ilp_vars(lpp_get_var_count(pi->curr_lp));
 601         copystat_add_ilp_csts(lpp_get_cst_count(pi->curr_lp));
 602         copystat_add_ilp_iter(lpp_get_iter_cnt(pi->curr_lp));
 603 #endif
 604 }
 605
 606 /**
 607  * Solves the problem using mixed integer programming
 608  * @returns 1 iff solution state was optimal
 609  * Uses the OU and the GRAPH data structure
 610  * Dependency of the OU structure can be removed
 611  */
 612 static int co_solve_ilp2(copy_opt_t *co)
 613 {
 614         unsigned        n_regs = arch_register_class_n_regs(co->cls);
 615         lpp_sol_state_t sol_state;
 616         ilp_env_t      *ienv;
 617         local_env_t     my;
 618
 619         ASSERT_OU_AVAIL(co); //See build_clique_st
 620         ASSERT_GS_AVAIL(co);
 621
 622         my.first_x_var = -1;
 623         my.last_x_var  = -1;
 624         FIRM_DBG_REGISTER(dbg, "firm.be.coilp2");
 625
 626         unsigned *const allocatable_colors = rbitset_alloca(n_regs);
 627         be_set_allocatable_regs(co->irg, co->cls, allocatable_colors);
 628         my.allocatable_colors = allocatable_colors;
 629
 630         ienv = new_ilp_env(co, ilp2_build, ilp2_apply, &my);
 631
 632         sol_state = ilp_go(ienv);
 633
 634         free_ilp_env(ienv);
 635
 636         return sol_state == lpp_optimal;
 637 }
 638
 639 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_copyilp2)
 640 void be_init_copyilp2(void)
 641 {
 642         static co_algo_info copyheur = {
 643                 co_solve_ilp2, 1
 644         };
 645
 646         be_register_copyopt("ilp", &copyheur);
 647 }