nsz Git - libfirm/blob - ir/be/becopyilp2.c

   1 /*
   2  * This file is part of libFirm.
   3  * Copyright (C) 2012 University of Karlsruhe.
   4  */
   5
   6 /**
   7  * @file
   8  * @brief       ILP based copy minimization.
   9  * @author      Daniel Grund
  10  * @date        28.02.2006
  11  *
  12  * ILP formalization using G=(V, E, Q):
  13  *  - 2 class of variables: coloring vars x_ic   and   equal color vars y_ij
  14  *  - Path constraints
  15  *  - Clique-star constraints
  16  *
  17  *
  18  * \min \sum_{ (i,j) \in Q }  w_ij y_ij
  19  *
  20  *     \sum_c x_nc           =  1           n \in N, c \in C
  21  *
  22  *     x_nc                  =  0           n \in N, c \not\in C(n)
  23  *
  24  *     \sum x_nc            <=  1           x_nc \in Clique \in AllCliques,  c \in C
  25  *
  26  *     \sum_{e \in p} y_e   >=  1           p \in P      path constraints
  27  *
  28  *     \sum_{e \in cs} y_e  >= |cs| - 1     cs \in CP    clique-star constraints
  29  *
  30  *     x_nc, y_ij \in N,   w_ij \in R^+
  31  */
  32 #include "config.h"
  33
  34 #include "be_t.h"
  35 #include "bitset.h"
  36 #include "error.h"
  37 #include "raw_bitset.h"
  38 #include "pdeq.h"
  39
  40 #include "util.h"
  41 #include "irgwalk.h"
  42 #include "becopyilp_t.h"
  43 #include "beifg.h"
  44 #include "besched.h"
  45 #include "bemodule.h"
  46
  47 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
  48
  49 typedef struct local_env_t {
  50         int             first_x_var;
  51         int             last_x_var;
  52         const unsigned *allocatable_colors;
  53 } local_env_t;
  54
  55 static unsigned check_alignment_constraints(ir_node *node)
  56 {
  57         const arch_register_req_t *req = arch_get_irn_register_req(node);
  58         // For larger than 1 variables, support only aligned constraints
  59         assert((arch_register_req_is(req, aligned) || req->width == 1) && "Unaligned large (width > 1) variables not supported");
  60         return arch_register_req_is(req, aligned) && req->width > 1;
  61 }
  62
  63 static void make_color_var_name(char *buf, size_t buf_size,
  64                                 const ir_node *node, unsigned color)
  65 {
  66         unsigned node_idx = get_irn_idx(node);
  67         snprintf(buf, buf_size, "x_%u_%u", node_idx, color);
  68 }
  69
  70 static void build_coloring_cstr(ilp_env_t *ienv)
  71 {
  72         local_env_t    *lenv   = (local_env_t*)ienv->env;
  73         be_ifg_t       *ifg    = ienv->co->cenv->ifg;
  74         unsigned        n_regs = arch_register_class_n_regs(ienv->co->cls);
  75         const unsigned *allocatable_colors = lenv->allocatable_colors;
  76         nodes_iter_t    iter;
  77         char            buf[32];
  78
  79         unsigned *const colors = rbitset_alloca(n_regs);
  80         be_ifg_foreach_node(ifg, &iter, irn) {
  81                 const arch_register_req_t *req;
  82                 unsigned                   col;
  83                 int                        cst_idx;
  84                 unsigned                   curr_node_color;
  85                 unsigned                   has_alignment_cstr;
  86
  87                 if (sr_is_removed(ienv->sr, irn))
  88                         continue;
  89
  90                 has_alignment_cstr = check_alignment_constraints(irn);
  91
  92                 req = arch_get_irn_register_req(irn);
  93
  94                 /* get assignable colors */
  95                 if (arch_register_req_is(req, limited)) {
  96                         rbitset_copy(colors, req->limited, n_regs);
  97                 } else {
  98                         rbitset_copy(colors, allocatable_colors, n_regs);
  99                 }
 100
 101                 /* add the coloring constraint */
 102                 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 1.0);
 103
 104                 curr_node_color = get_irn_col(irn);
 105                 for (col = 0; col < n_regs; ++col) {
 106                         int    var_idx;
 107                         double val;
 108                         if (!rbitset_is_set(colors, col)
 109                                 || (has_alignment_cstr && ((col % req->width) != 0)))
 110                                 continue;
 111
 112                         make_color_var_name(buf, sizeof(buf), irn, col);
 113                         var_idx = lpp_add_var(ienv->lp, buf, lpp_binary, 0.0);
 114                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
 115
 116                         val = (col == curr_node_color) ? 1.0 : 0.0;
 117                         lpp_set_start_value(ienv->lp, var_idx, val);
 118
 119                         lenv->last_x_var = var_idx;
 120                         if (lenv->first_x_var == -1)
 121                                 lenv->first_x_var = var_idx;
 122                 }
 123
 124                 /* add register constraint constraints */
 125                 for (col = 0; col < n_regs; ++col) {
 126                         int cst_idx;
 127                         int var_idx;
 128                         if (rbitset_is_set(colors, col)
 129                                 // for aligned variable, we set the unaligned part to 0
 130                                 && (!has_alignment_cstr || ((col % req->width) == 0)))
 131                                 continue;
 132
 133                         make_color_var_name(buf, sizeof(buf), irn, col);
 134                         cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 0.0);
 135                         var_idx = lpp_add_var(ienv->lp, buf, lpp_binary, 0.0);
 136                         lpp_set_start_value(ienv->lp, var_idx, 0.0);
 137                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
 138
 139                         lenv->last_x_var = var_idx;
 140                 }
 141         }
 142 }
 143
 144 static void build_interference_cstr(ilp_env_t *ienv)
 145 {
 146         lpp_t          *lpp      = ienv->lp;
 147         local_env_t    *lenv     = (local_env_t*)ienv->env;
 148         be_ifg_t       *ifg      = ienv->co->cenv->ifg;
 149         unsigned        n_colors = arch_register_class_n_regs(ienv->co->cls);
 150         ir_node       **clique   = ALLOCAN(ir_node*, n_colors);
 151         const unsigned *allocatable_colors = lenv->allocatable_colors;
 152         cliques_iter_t iter;
 153         int            size;
 154         unsigned       col;
 155         int            i;
 156
 157         /* for each maximal clique */
 158         be_ifg_foreach_clique(ifg, &iter, clique, &size) {
 159                 unsigned realsize = 0;
 160
 161                 for (i=0; i<size; ++i) {
 162                         if (!sr_is_removed(ienv->sr, clique[i]))
 163                                 ++realsize;
 164                 }
 165
 166                 if (realsize < 2)
 167                         continue;
 168
 169                 /* for all colors */
 170                 for (col=0; col<n_colors; ++col) {
 171                         int cst_idx;
 172                         if (!rbitset_is_set(allocatable_colors, col))
 173                                 continue;
 174
 175                         cst_idx = lpp_add_cst(lpp, NULL, lpp_less_equal, 1.0);
 176
 177                         /* for each member of this clique */
 178                         for (i=0; i<size; ++i) {
 179                                 ir_node *irn = clique[i];
 180                                 char     buf[32];
 181                                 int      var_idx;
 182                                 unsigned aligment_offset = 0;
 183
 184                                 if (sr_is_removed(ienv->sr, irn))
 185                                         continue;
 186
 187                                 // Use the first part of the large registers for all
 188                                 // interference, since it is the only colorable one.
 189                                 if (check_alignment_constraints(irn)) {
 190                                         const arch_register_req_t *req
 191                                                 = arch_get_irn_register_req(irn);
 192                                         aligment_offset = col % req->width;
 193                                 }
 194
 195                                 make_color_var_name(buf, sizeof(buf), irn,
 196                                                                         col - aligment_offset);
 197                                 var_idx = lpp_get_var_idx(lpp, buf);
 198                                 lpp_set_factor_fast(lpp, cst_idx, var_idx, 1);
 199                         }
 200                 }
 201         }
 202 }
 203
 204 static void make_affinity_var_name(char *buf, size_t buf_size,
 205                                    const ir_node *node1, const ir_node *node2)
 206 {
 207         unsigned n1 = get_irn_idx(node1);
 208         unsigned n2 = get_irn_idx(node2);
 209         if (n1 < n2) {
 210                 snprintf(buf, buf_size, "y_%u_%u", n1, n2);
 211         } else {
 212                 snprintf(buf, buf_size, "y_%u_%u", n2, n1);
 213         }
 214 }
 215
 216
 217 /**
 218  * TODO: Remove the dependency of the opt-units data structure
 219  *       by walking over all affinity edges. Graph structure
 220  *       does not provide this walker, yet.
 221  */
 222 static void build_affinity_cstr(ilp_env_t *ienv)
 223 {
 224         unsigned  n_colors = arch_register_class_n_regs(ienv->co->cls);
 225
 226         /* for all optimization units */
 227         list_for_each_entry(unit_t, curr, &ienv->co->units, units) {
 228                 ir_node *root     = curr->nodes[0];
 229                 unsigned root_col = get_irn_col(root);
 230                 int      i;
 231
 232                 for (i = 1; i < curr->node_count; ++i) {
 233                         ir_node *arg     = curr->nodes[i];
 234                         unsigned arg_col = get_irn_col(arg);
 235                         double   val;
 236                         char     buf[32];
 237                         unsigned col;
 238                         int      y_idx;
 239
 240                         /* add a new affinity variable */
 241                         make_affinity_var_name(buf, sizeof(buf), arg, root);
 242                         y_idx = lpp_add_var(ienv->lp, buf, lpp_binary, curr->costs[i]);
 243                         val   = (root_col == arg_col) ? 0.0 : 1.0;
 244                         lpp_set_start_value(ienv->lp, y_idx, val);
 245
 246                         /* add constraints relating the affinity var to the color vars */
 247                         for (col=0; col<n_colors; ++col) {
 248                                 int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_less_equal, 0.0);
 249                                 int root_idx;
 250                                 int arg_idx;
 251
 252                                 make_color_var_name(buf, sizeof(buf), root, col);
 253                                 root_idx = lpp_get_var_idx(ienv->lp, buf);
 254                                 make_color_var_name(buf, sizeof(buf), arg, col);
 255                                 arg_idx  = lpp_get_var_idx(ienv->lp, buf);
 256
 257                                 lpp_set_factor_fast(ienv->lp, cst_idx, root_idx,  1.0);
 258                                 lpp_set_factor_fast(ienv->lp, cst_idx, arg_idx,  -1.0);
 259                                 lpp_set_factor_fast(ienv->lp, cst_idx, y_idx, -1.0);
 260                         }
 261                 }
 262         }
 263 }
 264
 265 /**
 266  * Helping stuff for build_clique_star_cstr
 267  */
 268 typedef struct edge_t {
 269         ir_node *n1;
 270         ir_node *n2;
 271 } edge_t;
 272
 273 static int compare_edge_t(const void *k1, const void *k2, size_t size)
 274 {
 275         const edge_t *e1 = (const edge_t*)k1;
 276         const edge_t *e2 = (const edge_t*)k2;
 277         (void) size;
 278
 279         return ! (e1->n1 == e2->n1 && e1->n2 == e2->n2);
 280 }
 281
 282 #define HASH_EDGE(e) (hash_irn((e)->n1) ^ hash_irn((e)->n2))
 283
 284 static inline edge_t *add_edge(set *edges, ir_node *n1, ir_node *n2, size_t *counter)
 285 {
 286         edge_t new_edge;
 287
 288         if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
 289                 new_edge.n1 = n1;
 290                 new_edge.n2 = n2;
 291         } else {
 292                 new_edge.n1 = n2;
 293                 new_edge.n2 = n1;
 294         }
 295         (*counter)++;
 296         return set_insert(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 297 }
 298
 299 static inline edge_t *find_edge(set *edges, ir_node *n1, ir_node *n2)
 300 {
 301         edge_t new_edge;
 302
 303         if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
 304                 new_edge.n1 = n1;
 305                 new_edge.n2 = n2;
 306         } else {
 307                 new_edge.n1 = n2;
 308                 new_edge.n2 = n1;
 309         }
 310         return set_find(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 311 }
 312
 313 static inline void remove_edge(set *edges, ir_node *n1, ir_node *n2, size_t *counter)
 314 {
 315         edge_t new_edge, *e;
 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         e = set_find(edge_t, edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
 325         if (e) {
 326                 e->n1 = NULL;
 327                 e->n2 = NULL;
 328                 (*counter)--;
 329         }
 330 }
 331
 332 #define pset_foreach(pset, irn) foreach_pset((pset), ir_node, (irn))
 333
 334 /**
 335  * Search for an interference clique and an external node
 336  * with affinity edges to all nodes of the clique.
 337  * At most 1 node of the clique can be colored equally with the external node.
 338  */
 339 static void build_clique_star_cstr(ilp_env_t *ienv)
 340 {
 341         /* for each node with affinity edges */
 342         co_gs_foreach_aff_node(ienv->co, aff) {
 343                 struct obstack ob;
 344                 const ir_node *center = aff->irn;
 345                 ir_node **nodes;
 346                 set *edges;
 347                 int i, o, n_nodes;
 348                 size_t n_edges;
 349
 350                 if (arch_irn_is_ignore(aff->irn))
 351                         continue;
 352
 353                 obstack_init(&ob);
 354                 edges = new_set(compare_edge_t, 8);
 355
 356                 /* get all affinity neighbours */
 357                 n_nodes = 0;
 358                 co_gs_foreach_neighb(aff, nbr) {
 359                         if (!arch_irn_is_ignore(nbr->irn)) {
 360                                 obstack_ptr_grow(&ob, nbr->irn);
 361                                 ++n_nodes;
 362                         }
 363                 }
 364                 nodes = (ir_node**)obstack_finish(&ob);
 365
 366                 /* get all interference edges between these */
 367                 n_edges = 0;
 368                 for (i=0; i<n_nodes; ++i) {
 369                         for (o=0; o<i; ++o) {
 370                                 if (be_ifg_connected(ienv->co->cenv->ifg, nodes[i], nodes[o]))
 371                                         add_edge(edges, nodes[i], nodes[o], &n_edges);
 372                         }
 373                 }
 374
 375                 /* cover all these interference edges with maximal cliques */
 376                 while (n_edges) {
 377                         edge_t *e;
 378                         pset   *clique = pset_new_ptr(8);
 379                         bool    growed;
 380
 381                         /* get 2 starting nodes to form a clique */
 382                         for (e = set_first(edge_t, edges); !e->n1; e = set_next(edge_t, edges)) {}
 383
 384                         /* we could be stepped out of the loop before the set iterated to the end */
 385                         set_break(edges);
 386
 387                         pset_insert_ptr(clique, e->n1);
 388                         pset_insert_ptr(clique, e->n2);
 389                         remove_edge(edges, e->n1, e->n2, &n_edges);
 390
 391                         /* while the clique is growing */
 392                         do {
 393                                 growed = false;
 394
 395                                 /* search for a candidate to extend the clique */
 396                                 for (i=0; i<n_nodes; ++i) {
 397                                         ir_node *cand = nodes[i];
 398                                         bool     is_cand;
 399
 400                                         /* if its already in the clique try the next */
 401                                         if (pset_find_ptr(clique, cand))
 402                                                 continue;
 403
 404                                         /* are there all necessary interferences? */
 405                                         is_cand = true;
 406                                         pset_foreach(clique, member) {
 407                                                 if (!find_edge(edges, cand, member)) {
 408                                                         is_cand = false;
 409                                                         pset_break(clique);
 410                                                         break;
 411                                                 }
 412                                         }
 413
 414                                         /* now we know if we have a clique extender */
 415                                         if (is_cand) {
 416                                                 /* first remove all covered edges */
 417                                                 pset_foreach(clique, member)
 418                                                         remove_edge(edges, cand, member, &n_edges);
 419
 420                                                 /* insert into clique */
 421                                                 pset_insert_ptr(clique, cand);
 422                                                 growed = true;
 423                                                 break;
 424                                         }
 425                                 }
 426                         } while (growed);
 427
 428                         /* now the clique is maximal. Finally add the constraint */
 429                         {
 430                                 int  var_idx;
 431                                 int  cst_idx;
 432                                 char buf[32];
 433
 434                                 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater_equal, pset_count(clique)-1);
 435
 436                                 pset_foreach(clique, member) {
 437                                         make_affinity_var_name(buf, sizeof(buf), center, member);
 438                                         var_idx = lpp_get_var_idx(ienv->lp, buf);
 439                                         lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
 440                                 }
 441                         }
 442
 443                         del_pset(clique);
 444                 }
 445
 446                 del_set(edges);
 447                 obstack_free(&ob, NULL);
 448         }
 449 }
 450
 451 static void extend_path(ilp_env_t *ienv, pdeq *path, const ir_node *irn)
 452 {
 453         be_ifg_t *ifg = ienv->co->cenv->ifg;
 454         int i, len;
 455         ir_node **curr_path;
 456         affinity_node_t *aff;
 457
 458         /* do not walk backwards or in circles */
 459         if (pdeq_contains(path, irn))
 460                 return;
 461
 462         if (arch_irn_is_ignore(irn))
 463                 return;
 464
 465         /* insert the new irn */
 466         pdeq_putr(path, irn);
 467
 468         /* check for forbidden interferences */
 469         len       = pdeq_len(path);
 470         curr_path = ALLOCAN(ir_node*, len);
 471         pdeq_copyl(path, (const void **)curr_path);
 472
 473         for (i=1; i<len; ++i) {
 474                 if (be_ifg_connected(ifg, irn, curr_path[i]))
 475                         goto end;
 476         }
 477
 478         /* check for terminating interference */
 479         if (be_ifg_connected(ifg, irn, curr_path[0])) {
 480                 /* One node is not a path. */
 481                 /* And a path of length 2 is covered by a clique star constraint. */
 482                 if (len > 2) {
 483                         /* finally build the constraint */
 484                         int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater_equal, 1.0);
 485                         for (i=1; i<len; ++i) {
 486                                 char buf[32];
 487                                 int  var_idx;
 488
 489                                 make_affinity_var_name(buf, sizeof(buf), curr_path[i-1], curr_path[i]);
 490                                 var_idx = lpp_get_var_idx(ienv->lp, buf);
 491                                 lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
 492                         }
 493                 }
 494
 495                 /* this path cannot be extended anymore */
 496                 goto end;
 497         }
 498
 499         /* recursively extend the path */
 500         aff = get_affinity_info(ienv->co, irn);
 501         co_gs_foreach_neighb(aff, nbr) {
 502                 extend_path(ienv, path, nbr->irn);
 503         }
 504
 505 end:
 506         /* remove the irn */
 507         pdeq_getr(path);
 508 }
 509
 510 /**
 511  * Search a path of affinity edges, whose ends are connected
 512  * by an interference edge and there are no other interference
 513  * edges in between.
 514  * Then at least one of these affinity edges must break.
 515  */
 516 static void build_path_cstr(ilp_env_t *ienv)
 517 {
 518         /* for each node with affinity edges */
 519         co_gs_foreach_aff_node(ienv->co, aff_info) {
 520                 pdeq *path = new_pdeq();
 521
 522                 extend_path(ienv, path, aff_info->irn);
 523
 524                 del_pdeq(path);
 525         }
 526 }
 527
 528 static void ilp2_build(ilp_env_t *ienv)
 529 {
 530         int lower_bound;
 531
 532         ienv->lp = lpp_new(ienv->co->name, lpp_minimize);
 533         build_coloring_cstr(ienv);
 534         build_interference_cstr(ienv);
 535         build_affinity_cstr(ienv);
 536         build_clique_star_cstr(ienv);
 537         build_path_cstr(ienv);
 538
 539         lower_bound = co_get_lower_bound(ienv->co) - co_get_inevit_copy_costs(ienv->co);
 540         lpp_set_bound(ienv->lp, lower_bound);
 541 }
 542
 543 static void ilp2_apply(ilp_env_t *ienv)
 544 {
 545         local_env_t *lenv = (local_env_t*)ienv->env;
 546         ir_graph    *irg  = ienv->co->irg;
 547
 548         /* first check if there was sth. to optimize */
 549         if (lenv->first_x_var >= 0) {
 550                 int              count = lenv->last_x_var - lenv->first_x_var + 1;
 551                 double          *sol   = XMALLOCN(double, count);
 552                 lpp_sol_state_t  state = lpp_get_solution(ienv->lp, sol, lenv->first_x_var, lenv->last_x_var);
 553                 int              i;
 554
 555                 if (state != lpp_optimal) {
 556                         printf("WARNING %s: Solution state is not 'optimal': %d\n",
 557                                ienv->co->name, (int)state);
 558                         if (state < lpp_feasible) {
 559                                 panic("Copy coalescing solution not feasible!");
 560                         }
 561                 }
 562
 563                 for (i=0; i<count; ++i) {
 564                         unsigned nodenr;
 565                         unsigned color;
 566                         char     var_name[32];
 567                         if (sol[i] <= 1-EPSILON)
 568                                 continue;
 569                         /* split variable name into components */
 570                         lpp_get_var_name(ienv->lp, lenv->first_x_var+i, var_name, sizeof(var_name));
 571
 572                         if (sscanf(var_name, "x_%u_%u", &nodenr, &color) == 2) {
 573                                 ir_node *irn = get_idx_irn(irg, nodenr);
 574                                 set_irn_col(ienv->co->cls, irn, color);
 575                         } else {
 576                                 panic("This should be a x-var");
 577                         }
 578                 }
 579
 580                 xfree(sol);
 581         }
 582
 583 #ifdef COPYOPT_STAT
 584         /* TODO adapt to multiple possible ILPs */
 585         copystat_add_ilp_time((int)(1000.0*lpp_get_sol_time(pi->curr_lp)));  //now we have ms
 586         copystat_add_ilp_vars(lpp_get_var_count(pi->curr_lp));
 587         copystat_add_ilp_csts(lpp_get_cst_count(pi->curr_lp));
 588         copystat_add_ilp_iter(lpp_get_iter_cnt(pi->curr_lp));
 589 #endif
 590 }
 591
 592 /**
 593  * Solves the problem using mixed integer programming
 594  * @returns 1 iff solution state was optimal
 595  * Uses the OU and the GRAPH data structure
 596  * Dependency of the OU structure can be removed
 597  */
 598 static int co_solve_ilp2(copy_opt_t *co)
 599 {
 600         unsigned        n_regs = arch_register_class_n_regs(co->cls);
 601         lpp_sol_state_t sol_state;
 602         ilp_env_t      *ienv;
 603         local_env_t     my;
 604
 605         ASSERT_OU_AVAIL(co); //See build_clique_st
 606         ASSERT_GS_AVAIL(co);
 607
 608         my.first_x_var = -1;
 609         my.last_x_var  = -1;
 610         FIRM_DBG_REGISTER(dbg, "firm.be.coilp2");
 611
 612         unsigned *const allocatable_colors = rbitset_alloca(n_regs);
 613         be_set_allocatable_regs(co->irg, co->cls, allocatable_colors);
 614         my.allocatable_colors = allocatable_colors;
 615
 616         ienv = new_ilp_env(co, ilp2_build, ilp2_apply, &my);
 617
 618         sol_state = ilp_go(ienv);
 619
 620         free_ilp_env(ienv);
 621
 622         return sol_state == lpp_optimal;
 623 }
 624
 625 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_copyilp2)
 626 void be_init_copyilp2(void)
 627 {
 628         static co_algo_info copyheur = {
 629                 co_solve_ilp2, 1
 630         };
 631
 632         be_register_copyopt("ilp", &copyheur);
 633 }