4 * Copyright: (c) Universitaet Karlsruhe
5 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
8 * ILP formalization using G=(V, E, Q):
9 * - 2 class of variables: coloring vars x_ic and equal color vars y_ij
11 * - Clique-star constraints
14 * \min \sum_{ (i,j) \in Q } w_ij y_ij
16 * \sum_c x_nc = 1 n \in N, c \in C
18 * x_nc = 0 n \in N, c \not\in C(n)
20 * \sum x_nc <= 1 x_nc \in Clique \in AllCliques, c \in C
22 * \sum_{e \in p} y_e >= 1 p \in P path constraints
24 * \sum_{e \in cs} y_e >= |cs| - 1 cs \in CP clique-star constraints
26 * x_nc, y_ij \in N, w_ij \in R^+
31 #endif /* HAVE_CONFIG_H */
37 #include "becopyilp_t.h"
39 #include "besched_t.h"
43 typedef struct _local_env_t {
44 firm_dbg_module_t *dbg;
46 int first_x_var, last_x_var;
50 static void build_coloring_cstr(ilp_env_t *ienv) {
51 be_ifg_t *ifg = ienv->co->cenv->ifg;
52 void *iter = be_ifg_nodes_iter_alloca(ifg);
57 colors = bitset_alloca(arch_register_class_n_regs(ienv->co->cls));
59 be_ifg_foreach_node(ifg, iter, irn)
60 if (!sr_is_removed(ienv->sr, irn)) {
62 arch_register_req_t req;
63 int curr_node_color = get_irn_col(ienv->co, irn);
64 int node_nr = (int)get_irn_node_nr(irn);
65 local_env_t *lenv = ienv->env;
67 pmap_insert(lenv->nr_2_irn, INT_TO_PTR(node_nr), irn);
69 arch_get_register_req(ienv->co->aenv, &req, irn, -1);
71 /* get assignable colors */
72 if (arch_register_req_is(&req, limited))
73 req.limited(req.limited_env, colors);
75 arch_put_non_ignore_regs(ienv->co->aenv, req.cls, colors);
77 /* add the coloring constraint */
78 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 1.0);
80 bitset_foreach(colors, col) {
81 int var_idx = lpp_add_var(ienv->lp, name_cdd(buf, 'x', node_nr, col), lpp_binary, 0.0);
82 lpp_set_start_value(ienv->lp, var_idx, (col == curr_node_color) ? 1.0 : 0.0);
83 lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
85 lenv->last_x_var = var_idx;
86 if (lenv->first_x_var == -1)
87 lenv->first_x_var = var_idx;
90 /* add register constraint constraints */
91 bitset_foreach_clear(colors, col) {
92 int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 0.0);
93 int var_idx = lpp_add_var(ienv->lp, name_cdd(buf, 'x', node_nr, col), lpp_binary, 0.0);
94 lpp_set_start_value(ienv->lp, var_idx, 0.0);
95 lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
97 lenv->last_x_var = var_idx;
102 static void build_interference_cstr(ilp_env_t *ienv) {
103 lpp_t *lpp = ienv->lp;
104 be_ifg_t *ifg = ienv->co->cenv->ifg;
105 int n_colors = arch_register_class_n_regs(ienv->co->cls);
108 void *iter = be_ifg_cliques_iter_alloca(ifg);
109 ir_node **clique = alloca(sizeof(*clique) * n_colors);
114 /* for each maximal clique */
115 be_ifg_foreach_clique(ifg, iter, clique, &size) {
121 for (col=0; col<n_colors; ++col) {
122 int cst_idx = lpp_add_cst(lpp, NULL, lpp_less, 1.0);
124 /* for each member of this clique */
125 for (i=0; i<size; ++i) {
126 ir_node *irn = clique[i];
128 if (!sr_is_removed(ienv->sr, irn)) {
129 int var_idx = lpp_get_var_idx(lpp, name_cdd(buf, 'x', (int)get_irn_node_nr(irn), col));
130 lpp_set_factor_fast(lpp, cst_idx, var_idx, 1);
137 static void build_affinity_cstr(ilp_env_t *ienv) {
139 int n_colors = arch_register_class_n_regs(ienv->co->cls);
141 /* for all optimization units */
142 list_for_each_entry(unit_t, curr, &ienv->co->units, units) {
144 int root_nr, arg_nr, i, col, y_idx, root_idx, arg_idx;
146 int root_col, arg_col;
148 root = curr->nodes[0];
149 root_nr = (int) get_irn_node_nr(root);
150 root_col = get_irn_col(ienv->co, root);
152 for (i = 1; i < curr->node_count; ++i) {
153 arg = curr->nodes[i];
154 arg_nr = (int) get_irn_node_nr(arg);
155 arg_col = get_irn_col(ienv->co, arg);
157 /* add a new affinity variable */
158 y_idx = lpp_add_var(ienv->lp, name_cdd_sorted(buf, 'y', root_nr, arg_nr), lpp_binary, curr->costs[i]);
159 lpp_set_start_value(ienv->lp, y_idx, (root_col==arg_col) ? 0.0 : 1.0);
161 /* add constraints relating the affinity var to the color vars */
162 for (col=0; col<n_colors; ++col) {
163 int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_less, 0.0);
164 root_idx = lpp_get_var_idx(ienv->lp, name_cdd(buf, 'x', root_nr, col));
165 arg_idx = lpp_get_var_idx(ienv->lp, name_cdd(buf, 'x', arg_nr, col));
167 lpp_set_factor_fast(ienv->lp, cst_idx, root_idx, 1.0);
168 lpp_set_factor_fast(ienv->lp, cst_idx, arg_idx, -1.0);
169 lpp_set_factor_fast(ienv->lp, cst_idx, root_idx, -1.0);
176 * Helping stuff for build_clique_star_cstr
178 typedef struct _edge_t {
182 static int compare_edge_t(const void *k1, const void *k2, size_t size) {
183 const edge_t *e1 = k1;
184 const edge_t *e2 = k2;
186 return ! (e1->n1 == e2->n1 && e1->n2 == e2->n2);
189 #define HASH_EDGE(e) (HASH_PTR((e)->n1) ^ HASH_PTR((e)->n2))
191 static INLINE edge_t *add_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
194 if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
202 return set_insert(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
205 static INLINE edge_t *find_edge(set *edges, ir_node *n1, ir_node *n2) {
208 if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
215 return set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
218 static INLINE void remove_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
221 if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
228 e = set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
236 #define pset_foreach(pset, irn) for(irn=pset_first(pset); irn; irn=pset_next(pset))
239 * Search for an interference clique and an external node
240 * with affinity edges to all nodes of the clique.
241 * At most 1 node of the clique can be colored equally with the external node.
243 static void build_clique_star_cstr(ilp_env_t *ienv) {
246 /* for each node with affinity edges */
247 co_gs_foreach_node(ienv->co, node) {
250 ir_node *center = node->irn;
253 int i, o, n_nodes, n_edges;
256 edges = new_set(compare_edge_t, 8);
258 /* get all affinity neighbours */
260 co_gs_foreach_neighb(node, nbr) {
261 obstack_ptr_grow(&ob, nbr->irn);
264 nodes = obstack_finish(&ob);
266 /* get all interference edges between these */
268 for (i=0; i<n_nodes; ++i)
270 if (be_ifg_connected(ienv->co->cenv->ifg, nodes[i], nodes[o]))
271 add_edge(edges, nodes[i], nodes[o], &n_edges);
273 /* cover all these interference edges with maximal cliques */
276 pset *clique = pset_new_ptr(8);
279 /* get 2 starting nodes to form a clique */
280 for (e=set_first(edges); !e->n1; e=set_next(edges))
283 remove_edge(edges, e->n1, e->n2, &n_edges);
284 pset_insert_ptr(clique, e->n1);
285 pset_insert_ptr(clique, e->n2);
287 /* while the clique is growing */
291 /* search for a candidate to extend the clique */
292 for (i=0; i<n_nodes; ++i) {
293 ir_node *member, *cand = nodes[i];
296 /* if its already in the clique try the next */
297 if (pset_find_ptr(clique, cand))
300 /* are there all necessary interferences? */
302 pset_foreach(clique, member) {
303 if (!find_edge(edges, cand, member)) {
310 /* now we know if we have a clique extender */
312 /* first remove all covered edges */
313 pset_foreach(clique, member)
314 remove_edge(edges, cand, member, &n_edges);
316 /* insert into clique */
317 pset_insert_ptr(clique, cand);
324 /* now the clique is maximal. Finally add the constraint */
327 int var_idx, cst_idx, center_nr, member_nr;
330 cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater, pset_count(clique)-1);
331 center_nr = get_irn_node_nr(center);
333 pset_foreach(clique, member) {
334 member_nr = get_irn_node_nr(member);
335 var_idx = lpp_get_var_idx(ienv->lp, name_cdd_sorted(buf, 'y', center_nr, member_nr));
336 lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
344 obstack_free(&ob, NULL);
351 static void build_path_cstr(ilp_env_t *ienv) {
355 static void ilp2_build(ilp_env_t *ienv) {
356 local_env_t *lenv = ienv->env;
359 ienv->lp = new_lpp(ienv->co->name, lpp_minimize);
360 build_coloring_cstr(ienv);
361 build_interference_cstr(ienv);
362 build_affinity_cstr(ienv);
363 build_clique_star_cstr(ienv);
364 build_path_cstr(ienv);
366 lower_bound = co_get_lower_bound(ienv->co) - co_get_inevit_copy_costs(ienv->co);
367 lpp_set_bound(ienv->lp, lower_bound);
368 lpp_set_time_limit(ienv->lp, lenv->time_limit);
371 static void ilp2_apply(ilp_env_t *ienv) {
372 local_env_t *lenv = ienv->env;
374 lpp_sol_state_t state;
377 count = lenv->last_x_var - lenv->first_x_var + 1;
378 sol = xmalloc(count * sizeof(sol[0]));
379 state = lpp_get_solution(ienv->lp, sol, lenv->first_x_var, lenv->last_x_var);
380 if (state != lpp_optimal) {
381 printf("WARNING %s: Solution state is not 'optimal': %d\n", ienv->co->name, state);
382 assert(state >= lpp_feasible && "The solution should at least be feasible!");
385 for (i=0; i<count; ++i) {
389 if (sol[i] > 1-EPSILON) { /* split variable name into components */
390 lpp_get_var_name(ienv->lp, lenv->first_x_var+i, var_name, sizeof(var_name));
392 if (sscanf(var_name, "x_%d_%d", &nodenr, &color) == 2) {
393 ir_node *irn = pmap_get(lenv->nr_2_irn, INT_TO_PTR(nodenr));
394 assert(irn && "This node number must be present in the map");
396 set_irn_col(ienv->co, irn, color);
398 assert(0 && "This should be a x-var");
403 /* TODO adapt to multiple possible ILPs */
404 copystat_add_ilp_time((int)(1000.0*lpp_get_sol_time(pi->curr_lp))); //now we have ms
405 copystat_add_ilp_vars(lpp_get_var_count(pi->curr_lp));
406 copystat_add_ilp_csts(lpp_get_cst_count(pi->curr_lp));
407 copystat_add_ilp_iter(lpp_get_iter_cnt(pi->curr_lp));
411 int co_solve_ilp2(copy_opt_t *co, double time_limit) {
412 lpp_sol_state_t sol_state;
416 my.time_limit = time_limit;
419 my.nr_2_irn = pmap_create();
420 my.dbg = firm_dbg_register("ir.be.coilp2");
421 firm_dbg_set_mask(my.dbg, DEBUG_LVL);
423 ienv = new_ilp_env(co, ilp2_build, ilp2_apply, &my);
425 sol_state = ilp_go(ienv);
427 pmap_destroy(my.nr_2_irn);
430 return sol_state == lpp_optimal;
435 static void only_that_you_can_compile_without_WITH_ILP_defined(void) {
438 #endif /* WITH_ILP */