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

   1 /**
   2  * Author:      Daniel Grund
   3  * Date:                17.05.2005
   4  * Copyright:   (c) Universitaet Karlsruhe
   5  * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
   6  */
   7 #ifdef HAVE_CONFIG_H
   8 #include "config.h"
   9 #endif
  10
  11 #ifdef HAVE_ALLOCA_H
  12 #include <alloca.h>
  13 #endif
  14 #ifdef HAVE_MALLOC_H
  15 #include <malloc.h>
  16 #endif
  17
  18 #include "irprog.h"
  19
  20 #include <lpp/lpp.h>
  21 #include <lpp/lpp_net.h>
  22 #include "xmalloc.h"
  23 #include "becopyopt.h"
  24 #include "becopystat.h"
  25 #include "besched_t.h"
  26
  27 #define LPP_HOST "i44pc52"
  28 #define LPP_SOLVER "cplex"
  29
  30 #undef DUMP_MPS
  31 #define DEBUG_LVL SET_LEVEL_1
  32 static firm_dbg_module_t *dbg = NULL;
  33
  34 #define MAX(a,b) ((a<b)?(b):(a))
  35 #define EPSILON 0.00001
  36 #define SLOTS_LIVING 32
  37
  38 typedef struct _simpl_t {
  39         struct list_head chain;
  40         if_node_t *ifn;
  41 } simpl_t;
  42
  43 typedef struct _problem_instance_t {
  44         const copy_opt_t *co;                   /** the copy_opt problem */
  45         /* problem size reduction removing simple nodes */
  46         struct list_head simplicials;   /**< holds all simpl_t's in right order to color*/
  47         pset *removed;                                  /**< holds all removed simplicial irns */
  48         /* lp problem */
  49         lpp_t *dilp;                                    /**< problem formulation directly as milp */
  50         /* overhead stuff */
  51         lpp_t *curr_lp;                                 /**< points to the problem currently used */
  52         int cst_counter, last_x_var;
  53         char buf[32];
  54         int all_simplicial;
  55 } problem_instance_t;
  56
  57 #define is_removed(irn) pset_find_ptr(pi->removed, irn)
  58
  59 #define is_color_possible(irn,color) arch_reg_is_allocatable(pi->co->chordal_env->arch_env, irn, arch_pos_make_out(0), arch_register_for_index(pi->co->chordal_env->cls, color))
  60
  61 /*
  62  * Some stuff for variable name handling.
  63  */
  64 #define mangle_cst(buf, prefix, nr) \
  65                         snprintf((buf), sizeof(buf), "%c%d", (prefix), (nr))
  66
  67 #define mangle_var(buf, prefix, node_nr, color) \
  68                         snprintf((buf), sizeof(buf), "%c%d_%d", (prefix), (node_nr), (color))
  69
  70 #define mangle_var_irn(buf, prefix, irn, color) \
  71                         mangle_var((buf), (prefix), get_irn_graph_nr(irn), (color))
  72
  73 #define split_var(var, nnr, col) \
  74                         sscanf(var, "x%d_%d", (nnr), (col))
  75
  76
  77 /**
  78  * Checks if a node is simplicial in the graph
  79  * heeding the already removed nodes.
  80  */
  81 static INLINE int pi_is_simplicial(problem_instance_t *pi, const if_node_t *ifn) {
  82         int i, o, size = 0;
  83         if_node_t **all, *curr;
  84         all = alloca(ifn_get_degree(ifn) * sizeof(*all));
  85
  86         /* get all non-removed neighbors */
  87         foreach_neighb(ifn, curr)
  88                 if (!is_removed(curr))
  89                         all[size++] = curr;
  90
  91         /* check if these form a clique */
  92         for (i=0; i<size; ++i)
  93                 for (o=i+1; o<size; ++o)
  94                         if (!ifg_has_edge(pi->co->chordal_env, all[i], all[o]))
  95                                 return 0;
  96
  97         /* all edges exist so this is a clique */
  98         return 1;
  99 }
 100
 101 /**
 102  * Iterative finds and 'removes' from the graph all nodes which are
 103  * simplicial AND not member of a equal-color-wish
 104  */
 105 static void pi_find_simplicials(problem_instance_t *pi) {
 106         set *if_nodes;
 107         if_node_t *ifn;
 108         int redo = 1;
 109
 110         DBG((dbg, LEVEL_2, "Find simlicials...\n"));
 111
 112         if_nodes = be_ra_get_ifg_nodes(pi->co->chordal_env);
 113         while (redo) {
 114                 redo = 0;
 115                 for (ifn = set_first(if_nodes); ifn; ifn = set_next(if_nodes)) {
 116                         ir_node *irn = get_irn_for_graph_nr(pi->co->chordal_env->irg, ifn->nnr);
 117                         if (!is_removed(irn) && !is_optimizable(pi->co->chordal_env->arch_env, irn) &&
 118           !is_optimizable_arg(pi->co, irn) && pi_is_simplicial(pi, ifn)) {
 119                                 simpl_t *s = xmalloc(sizeof(*s));
 120                                 s->ifn = ifn;
 121                                 list_add(&s->chain, &pi->simplicials);
 122                                 pset_insert_ptr(pi->removed, irn);
 123                                 redo = 1;
 124                                 DBG((dbg, LEVEL_2, " Removed %n %d\n", irn, get_irn_graph_nr(irn)));
 125                         }
 126                 }
 127         }
 128         if (set_count(be_ra_get_ifg_nodes(pi->co->chordal_env)) == pset_count(pi->removed))
 129                 pi->all_simplicial = 1;
 130 }
 131
 132 /**
 133  * Add coloring-force conditions
 134  * Matrix A: knapsack constraint for each node
 135  */
 136 static void pi_add_constr_A(problem_instance_t *pi) {
 137         pmap_entry *pme;
 138
 139         DBG((dbg, LEVEL_2, "Add A constraints...\n"));
 140         /* iterate over all blocks */
 141         pmap_foreach(pi->co->chordal_env->border_heads, pme) {
 142                 struct list_head *head = pme->value;
 143                 border_t *curr;
 144                 bitset_t *pos_regs = bitset_alloca(pi->co->chordal_env->cls->n_regs);
 145
 146                 list_for_each_entry_reverse(border_t, curr, head, list)
 147                         if (curr->is_def && curr->is_real && !is_removed(curr->irn)) {
 148                                 int cst_idx, nnr, col;
 149
 150                                 nnr = get_irn_graph_nr(curr->irn);
 151                                 mangle_cst(pi->buf, 'A', nnr);
 152                                 cst_idx = lpp_add_cst(pi->curr_lp, pi->buf, lpp_equal, 1);
 153
 154                                 // iterate over all possible colors in order
 155                                 bitset_clear_all(pos_regs);
 156                                 arch_get_allocatable_regs(pi->co->chordal_env->arch_env, curr->irn, arch_pos_make_out(0), pi->co->chordal_env->cls, pos_regs);
 157                                 bitset_foreach(pos_regs, col) {
 158                                         int var_idx;
 159                                         mangle_var(pi->buf, 'x', nnr, col);
 160                                         var_idx = lpp_add_var(pi->curr_lp, pi->buf, lpp_binary, 0);
 161                                         pi->last_x_var = var_idx;
 162                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, var_idx, 1);
 163                                 }
 164                         }
 165         }
 166 }
 167
 168 /**
 169  * Checks if all nodes in @p living are live in in block @p block.
 170  * @return 1 if all are live in
 171  *         0 else
 172  */
 173 static INLINE int all_live_in(ir_node *block, pset *living) {
 174         ir_node *n;
 175         for (n = pset_first(living); n; n = pset_next(living))
 176                 if (!is_live_in(block, n)) {
 177                         pset_break(living);
 178                         return 0;
 179                 }
 180         return 1;
 181 }
 182
 183 /**
 184  * Finds cliques in the interference graph, considering only nodes
 185  * for which the color @p color is possible. Finds only 'maximal-cliques',
 186  * viz cliques which are not contained in another one.
 187  * Matrix B: interference constraints using cliques
 188  */
 189 static void pi_add_constr_B(problem_instance_t *pi, int color) {
 190         enum phase_t {growing, shrinking} phase = growing;
 191         border_t *b;
 192         pmap_entry *pme;
 193         pset *living = pset_new_ptr(SLOTS_LIVING);
 194
 195         DBG((dbg, LEVEL_2, "Add B constraints (col = %d)...\n", color));
 196         /* iterate over all blocks */
 197         pmap_foreach(pi->co->chordal_env->border_heads, pme) {
 198                 ir_node *block = pme->key;
 199                 struct list_head *head = pme->value;
 200
 201                 list_for_each_entry_reverse(border_t, b, head, list) {
 202                         const ir_node *irn = b->irn;
 203                         if (is_removed(irn) || !is_color_possible(irn, color))
 204                                 continue;
 205
 206                         if (b->is_def) {
 207                                 DBG((dbg, LEVEL_2, "Def %n\n", irn));
 208                                 pset_insert_ptr(living, irn);
 209                                 phase = growing;
 210                         } else { /* is_use */
 211                                 DBG((dbg, LEVEL_2, "Use %n\n", irn));
 212
 213                                 /* before shrinking the set, store the current 'maximum' clique;
 214                                  * do NOT if clique is a single node
 215                                  * do NOT if all values are live_in (in this case they were contained in a live-out clique elsewhere) */
 216                                 if (phase == growing && pset_count(living) >= 2 && !all_live_in(block, living)) {
 217                                         int cst_idx;
 218                                         ir_node *n;
 219                                         mangle_cst(pi->buf, 'B', pi->cst_counter);
 220                                         cst_idx = lpp_add_cst(pi->curr_lp, pi->buf, lpp_less, 1);
 221                                         for (n = pset_first(living); n; n = pset_next(living)) {
 222                                                 int var_idx;
 223                                                 mangle_var_irn(pi->buf, 'x', n, color);
 224                                                 var_idx = lpp_get_var_idx(pi->curr_lp, pi->buf);
 225                                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, var_idx, 1);
 226                                         }
 227                                         pi->cst_counter++;
 228                                 }
 229                                 pset_remove_ptr(living, irn);
 230                                 phase = shrinking;
 231                         }
 232                 }
 233         }
 234         assert(0 == pset_count(living));
 235         del_pset(living);
 236 }
 237
 238 /**
 239  * Generates constraints which interrelate x with y variables.
 240  * x1 and x2 have the different colors ==> y_12 = 1
 241  */
 242 static void pi_add_constr_E(problem_instance_t *pi) {
 243         unit_t *curr;
 244         bitset_t *root_regs, *arg_regs, *work_regs;
 245         int cst_counter = 0;
 246         unsigned nregs = pi->co->chordal_env->cls->n_regs;
 247         root_regs = bitset_alloca(nregs);
 248         arg_regs = bitset_alloca(nregs);
 249         work_regs = bitset_alloca(nregs);
 250
 251         DBG((dbg, LEVEL_2, "Add E constraints...\n"));
 252         /* for all roots of optimization units */
 253         list_for_each_entry(unit_t, curr, &pi->co->units, units) {
 254                 ir_node *root, *arg;
 255                 int rootnr, argnr, color;
 256                 int y_idx, i;
 257                 char buf[32];
 258
 259                 root = curr->nodes[0];
 260                 rootnr = get_irn_graph_nr(root);
 261                 bitset_clear_all(root_regs);
 262                 arch_get_allocatable_regs(pi->co->chordal_env->arch_env, root, arch_pos_make_out(0), pi->co->chordal_env->cls, root_regs);
 263
 264                 /* for all arguments of root */
 265                 for (i = 1; i < curr->node_count; ++i) {
 266                         arg = curr->nodes[i];
 267                         argnr = get_irn_graph_nr(arg);
 268                         bitset_clear_all(arg_regs);
 269                         arch_get_allocatable_regs(pi->co->chordal_env->arch_env, arg, arch_pos_make_out(0), pi->co->chordal_env->cls, arg_regs);
 270
 271                         /* Introduce new variable and set factor in objective function */
 272                         mangle_var(buf, 'y', rootnr, argnr);
 273                         y_idx = lpp_add_var(pi->curr_lp, buf, lpp_continous, curr->costs[i]);
 274
 275                         //BETTER: y vars as binary or continous vars ??
 276                         /* set starting value */
 277                         //lpp_set_start_value(pi->curr_lp, y_idx, (get_irn_col(pi->co, root) != get_irn_col(pi->co, arg)));
 278
 279                         /* For all colors root and arg have in common, add 2 constraints to E */
 280                         bitset_copy(work_regs, root_regs);
 281                         bitset_and(work_regs, arg_regs);
 282                         bitset_foreach(work_regs, color) {
 283                                 int root_idx, arg_idx, cst_idx;
 284                                 mangle_var(buf, 'x', rootnr, color);
 285                                 root_idx = lpp_get_var_idx(pi->curr_lp, buf);
 286                                 mangle_var(buf, 'x', argnr, color);
 287                                 arg_idx = lpp_get_var_idx(pi->curr_lp, buf);
 288
 289                                 /* add root-arg-y <= 0 */
 290                                 mangle_cst(buf, 'E', cst_counter++);
 291                                 cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
 292                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, 1);
 293                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, -1);
 294                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
 295
 296                                 /* add arg-root-y <= 0 */
 297                                 mangle_cst(buf, 'E', cst_counter++);
 298                                 cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
 299                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, -1);
 300                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, 1);
 301                                 lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
 302                         }
 303                         /* For all colors root and arg have "disjunct", add 1 constraints to E.
 304                          * If root gets a color the arg is not possible to get then they will
 305                          * definetly get different colors. So y has to be 1.
 306                          * Vice versa for arg.
 307                          */
 308                         bitset_copy(work_regs, root_regs);
 309                         bitset_xor(work_regs, arg_regs);
 310                         bitset_foreach(work_regs, color) {
 311                                 int root_idx, arg_idx, cst_idx;
 312                                 mangle_var(buf, 'x', rootnr, color);
 313                                 root_idx = lpp_get_var_idx(pi->curr_lp, buf);
 314                                 mangle_var(buf, 'x', argnr, color);
 315                                 arg_idx = lpp_get_var_idx(pi->curr_lp, buf);
 316
 317                                 mangle_cst(buf, 'E', cst_counter++);
 318                                 cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
 319                                 if (bitset_is_set(root_regs, color)) {
 320                                         /* add root-y <= 0 */
 321                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, 1);
 322                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
 323                                 } else {
 324                                         assert(bitset_is_set(arg_regs, color) && "bitset_xor is buggy");
 325                                         /* add arg-y <= 0 */
 326                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, 1);
 327                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
 328                                 }
 329                         }
 330                 }
 331         }
 332 }
 333
 334 /**
 335  * Matrix S: maximum independent set constraints
 336  * Generates lower bound-cuts for optimization units with inner interferences.
 337  * Sum(y_{root, arg}, arg \in Args) <= max_indep_set_size - 1
 338  */
 339 static void pi_add_constr_S(problem_instance_t *pi) {
 340         unit_t *curr;
 341         int cst_counter = 0;
 342         DBG((dbg, LEVEL_2, "Add S constraints...\n"));
 343
 344         /* for all optimization units */
 345         list_for_each_entry(unit_t, curr, &pi->co->units, units) {
 346                 const ir_node *root, *arg;
 347                 int rootnr, argnr;
 348                 int cst_idx, y_idx, i;
 349                 char buf[32];
 350
 351                 if (curr->minimal_costs == 0)
 352                         continue;
 353
 354                 root = curr->nodes[0];
 355                 rootnr = get_irn_graph_nr(root);
 356                 mangle_cst(buf, 'S', cst_counter++);
 357                 cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_greater, curr->minimal_costs);
 358
 359                 /* for all arguments */
 360                 for (i = 1; i < curr->node_count; ++i) {
 361                         arg = curr->nodes[i];
 362                         argnr = get_irn_graph_nr(arg);
 363                         mangle_var(buf, 'y', rootnr, argnr);
 364                         y_idx = lpp_get_var_idx(pi->curr_lp, buf);
 365                         lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, curr->costs[i]);
 366                 }
 367         }
 368 }
 369
 370 static INLINE int get_costs(problem_instance_t *pi, ir_node *phi, ir_node *irn) {
 371         int i;
 372         unit_t *curr;
 373         /* search optimization unit for phi */
 374         list_for_each_entry(unit_t, curr, &pi->co->units, units)
 375                 if (curr->nodes[0] == phi) {
 376                         for (i=1; i<curr->node_count; ++i)
 377                                 if (curr->nodes[i] == irn)
 378                                         return curr->costs[i];
 379                         assert(0 && "irn must occur in this ou");
 380                 }
 381         assert(0 && "phi must be found in a ou");
 382         return 0;
 383 }
 384
 385 static void M_constr_walker(ir_node *block, void *env) {
 386         problem_instance_t *pi = env;
 387         int count, arity, row, col, other_row, *costs;
 388         ir_node **phis, *phi, *irn, **phi_matrix;
 389         pset *done;
 390         bitset_t *candidates;
 391
 392         /* Count all phi nodes of this block */
 393         for (count=0, irn = sched_first(block); is_Phi(irn); irn = sched_next(irn))
 394                 count++;
 395
 396         /* We at least 2 phi nodes for this class of inequalities */
 397         if (count < 2)
 398                 return;
 399
 400         /* Build the \Phi-Matrix */
 401         arity = get_irn_arity(sched_first(block));
 402         phis = alloca(count * sizeof(*phis));
 403         costs = alloca(count * sizeof(costs));
 404         phi_matrix = alloca(count*arity * sizeof(*phi_matrix));
 405         candidates = bitset_alloca(count);
 406
 407         phi = sched_first(block);
 408         for (row=0; row<count; ++row) {
 409                 phis[row] = phi;
 410                 for (col=0; col<arity; ++col)
 411                         phi_matrix[row*arity + col] = get_irn_n(phi, col);
 412                 phi = sched_next(phi);
 413         }
 414
 415         /* Now find the interesting patterns in the matrix:
 416          * All nodes which are used at least twice in a column. */
 417         /* columnwise ... */
 418         for (col=0; col<arity; ++col) {
 419                 done = pset_new_ptr_default();
 420                 for (row=0; row<count; ++row) {
 421                         irn = phi_matrix[row*arity + col];
 422                         /* has the irn already been processed in this col? */
 423                         if (pset_find_ptr(done, irn))
 424                                 continue;
 425                         else
 426                                 pset_insert_ptr(done, irn);
 427
 428                         /* insert irn in candidates */
 429                         bitset_clear_all(candidates);
 430                         bitset_set(candidates, row);
 431                         /* search the irn in the rows below */
 432                         for (other_row = row+1; other_row<count; ++other_row)
 433                                 if (irn == phi_matrix[other_row*arity + col]) {
 434                                         /* found the irn in the same col in another row */
 435                                         bitset_set(candidates, other_row);
 436                                 }
 437
 438                         /* now we know all occurences of irn in this col */
 439                         if (bitset_popcnt(candidates) < 2)
 440                                 continue;
 441
 442                         /* compute the minimal costs (rhs) */
 443                         int phi_nr, sum=0, max=-1, minimal_costs;
 444                         bitset_foreach(candidates, phi_nr) {
 445                                 costs[phi_nr] = get_costs(pi, phis[phi_nr], irn);
 446                                 sum += costs[phi_nr];
 447                                 max = MAX(max, costs[phi_nr]);
 448                         }
 449                         minimal_costs = sum - max;
 450
 451                         /* generate an unequation finally.
 452                          * phis are indexed in the bitset,
 453                          * shared argument is irn
 454                          * rhs is minimal_costs */
 455                         {
 456                                 char buf[32];
 457                                 ir_node *root;
 458                                 int pos, irnnr, rootnr, cst_idx, y_idx, cst_counter = 0;
 459
 460                                 irnnr = get_irn_graph_nr(irn);
 461                                 mangle_cst(buf, 'M', cst_counter++);
 462                                 cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_greater, minimal_costs);
 463
 464                                 /* for all phis */
 465                                 bitset_foreach(candidates, pos) {
 466                                         root = phis[pos];
 467                                         rootnr = get_irn_graph_nr(root);
 468                                         mangle_var(buf, 'y', rootnr, irnnr);
 469                                         y_idx = lpp_get_var_idx(pi->curr_lp, buf);
 470                                         lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, costs[pos]);
 471                                 }
 472                         }
 473                 }
 474                 del_pset(done); /* clear set for next row */
 475         } /*next col*/
 476 }
 477
 478 /**
 479  * Matrix M: Multi-Arg-Use. Interrelates different \phi-functions
 480  * in the same block, iff they use the same arg at the same pos.
 481  * Only one of the phis can get the arg.
 482  */
 483 static void pi_add_constr_M(problem_instance_t *pi) {
 484         dom_tree_walk_irg(pi->co->chordal_env->irg, M_constr_walker, NULL, pi);
 485 }
 486
 487 /**
 488  * Generate the initial problem matrices and vectors.
 489  */
 490 static problem_instance_t *new_pi(const copy_opt_t *co) {
 491         problem_instance_t *pi;
 492         int col;
 493
 494         DBG((dbg, LEVEL_2, "Generating new instance...\n"));
 495         pi = xcalloc(1, sizeof(*pi));
 496         pi->co = co;
 497         pi->removed = pset_new_ptr_default();
 498         INIT_LIST_HEAD(&pi->simplicials);
 499         pi->dilp = new_lpp(co->name, lpp_minimize);
 500         pi->last_x_var = -1;
 501
 502         /* problem size reduction */
 503         pi_find_simplicials(pi);
 504         //BETTER If you wish to see it: dump_ifg_w/o_removed
 505         if (pi->all_simplicial)
 506                 return pi;
 507
 508         /* built objective abd constraints */
 509         pi->curr_lp = pi->dilp;
 510         pi_add_constr_A(pi);
 511         for (col = 0; col < pi->co->chordal_env->cls->n_regs; ++col)
 512                 pi_add_constr_B(pi, col);
 513         pi_add_constr_E(pi);
 514         pi_add_constr_S(pi);
 515         pi_add_constr_M(pi);
 516
 517         return pi;
 518 }
 519
 520 /**
 521  * Clean the problem instance
 522  */
 523 static void free_pi(problem_instance_t *pi) {
 524         simpl_t *simpl, *tmp;
 525
 526         DBG((dbg, LEVEL_2, "Free instance...\n"));
 527         free_lpp(pi->dilp);
 528         list_for_each_entry_safe(simpl_t, simpl, tmp, &pi->simplicials, chain)
 529                 free(simpl);
 530         del_pset(pi->removed);
 531         free(pi);
 532 }
 533
 534 /**
 535  * Set starting values for the mip problem according
 536  * to the current coloring of the graph.
 537  */
 538 static void pi_set_start_sol(problem_instance_t *pi) {
 539         int i;
 540         char var_name[64];
 541         DBG((dbg, LEVEL_2, "Set start solution...\n"));
 542         for (i=1; i<=pi->last_x_var; ++i) {
 543                 int nnr, col;
 544                 double val;
 545                 /* get variable name */
 546                 lpp_get_var_name(pi->curr_lp, i, var_name, sizeof(var_name));
 547                 /* split into components */
 548                 if (split_var(var_name, &nnr, &col) == 2) {
 549                         assert(get_irn_col(pi->co, get_irn_for_graph_nr(pi->co->chordal_env->irg, nnr)) != -1);
 550                         val = (get_irn_col(pi->co, get_irn_for_graph_nr(pi->co->chordal_env->irg, nnr)) == col) ? 1 : 0;
 551                         lpp_set_start_value(pi->curr_lp, i, val);
 552                 } else {
 553                         fprintf(stderr, "Variable name is: %s\n", var_name);
 554                         assert(0 && "x vars always look like this 'x123_45'");
 555                 }
 556         }
 557 }
 558
 559 /**
 560  * Invoke a solver
 561  */
 562 static void pi_solve_ilp(problem_instance_t *pi) {
 563         pi_set_start_sol(pi);
 564         lpp_solve_net(pi->curr_lp, LPP_HOST, LPP_SOLVER);
 565 }
 566
 567 /**
 568  * Set the color of all simplicial nodes removed form
 569  * the graph before transforming it to an ilp.
 570  */
 571 static void pi_set_simplicials(problem_instance_t *pi) {
 572         simpl_t *simpl, *tmp;
 573         bitset_t *used_cols = bitset_alloca(arch_register_class_n_regs(pi->co->chordal_env->cls));
 574
 575         DBG((dbg, LEVEL_2, "Set simplicials...\n"));
 576         /* color the simplicial nodes in right order */
 577         list_for_each_entry_safe(simpl_t, simpl, tmp, &pi->simplicials, chain) {
 578                 int free_col;
 579                 ir_node *other_irn, *irn;
 580                 if_node_t *other, *ifn;
 581
 582                 /* get free color by inspecting all neighbors */
 583                 ifn = simpl->ifn;
 584                 irn = get_irn_for_graph_nr(pi->co->chordal_env->irg, ifn->nnr);
 585                 bitset_clear_all(used_cols);
 586                 foreach_neighb(ifn, other) {
 587                         other_irn = get_irn_for_graph_nr(pi->co->chordal_env->irg, other->nnr);
 588                         if (!is_removed(other_irn)) /* only inspect nodes which are in graph right now */
 589                                 bitset_set(used_cols, get_irn_col(pi->co, other_irn));
 590                 }
 591
 592                 /* now all bits not set are possible colors */
 593                 free_col = bitset_next_clear(used_cols, 0);
 594                 assert(free_col != -1 && "No free color found. This can not be.");
 595                 set_irn_col(pi->co, irn, free_col);
 596                 pset_remove_ptr(pi->removed, irn); /* irn is back in graph again */
 597         }
 598 }
 599
 600 /**
 601  * Sets the colors of irns according to the values of variables
 602  * provided by the solution of the solver.
 603  */
 604 static void pi_apply_solution(problem_instance_t *pi) {
 605         int i;
 606         double *sol;
 607         lpp_sol_state_t state;
 608         DBG((dbg, LEVEL_2, "Applying solution...\n"));
 609
 610 #ifdef DO_STAT
 611         curr_vals[I_ILP_ITER] += lpp_get_iter_cnt(pi->curr_lp);
 612         curr_vals[I_ILP_TIME] += lpp_get_sol_time(pi->curr_lp);
 613 #endif
 614
 615         sol = xmalloc((pi->last_x_var+1) * sizeof(*sol));
 616         state = lpp_get_solution(pi->curr_lp, sol, 1, pi->last_x_var);
 617         if (state != lpp_optimal) {
 618                 printf("Solution state is not 'optimal': %d\n", state);
 619                 assert(state >= lpp_feasible && "The solution should at least be feasible!");
 620         }
 621         for (i=0; i<pi->last_x_var; ++i) {
 622                 int nnr, col;
 623                 char var_name[64];
 624
 625                 if (sol[i] > 1-EPSILON) { /* split varibale name into components */
 626                         lpp_get_var_name(pi->curr_lp, 1+i, var_name, sizeof(var_name));
 627                         if (split_var(var_name, &nnr, &col) == 2) {
 628                                 DBG((dbg, LEVEL_2, "Irn %n  Idx %d  Var %s  Val %f\n", get_irn_for_graph_nr(pi->co->chordal_env->irg, nnr), i, var_name, sol[i]));
 629                                 DBG((dbg, LEVEL_2, "x%d = %d\n", nnr, col));
 630                                 set_irn_col(pi->co, get_irn_for_graph_nr(pi->co->chordal_env->irg, nnr), col);
 631                         } else
 632                                 assert(0 && "This should be a x-var");
 633                 }
 634         }
 635 }
 636
 637 void co_ilp_opt(copy_opt_t *co) {
 638         problem_instance_t *pi;
 639
 640         dbg = firm_dbg_register("ir.be.copyoptilp");
 641         if (!strcmp(co->name, DEBUG_IRG))
 642                 firm_dbg_set_mask(dbg, DEBUG_LVL_ILP);
 643         else
 644                 firm_dbg_set_mask(dbg, DEBUG_LVL);
 645
 646         pi = new_pi(co);
 647         if (!pi->all_simplicial) {
 648 #ifdef DUMP_MPS
 649                 char buf[512];
 650                 snprintf(buf, sizeof(buf), "%s.mps", co->name);
 651                 lpp_dump(pi->curr_lp, buf);
 652 #endif
 653                 pi_solve_ilp(pi);
 654                 pi_apply_solution(pi);
 655                 pi_set_simplicials(pi);
 656         }
 657         free_pi(pi);
 658 }