* Copyright: (c) Universitaet Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*
+ *
* ILP formalization using G=(V, E, Q):
- * - 1 class of variables: equal color vars
+ * - 2 class of variables: coloring vars x_ic and equal color vars y_ij
* - Path constraints
- * - Clique path constraints
+ * - Clique-star constraints
*
*
* \min \sum_{ (i,j) \in Q } w_ij y_ij
*
- * y_ij = 1 (i,j) \in E
+ * \sum_c x_nc = 1 n \in N, c \in C
*
- * \sum_c y_nc = |C| - 1 n \in N, c \in C
+ * x_nc = 0 n \in N, c \not\in C(n)
*
- * y_nc = 1 n \in N, c \not\in C(n)
+ * \sum x_nc <= 1 x_nc \in Clique \in AllCliques, c \in C
*
* \sum_{e \in p} y_e >= 1 p \in P path constraints
*
- * \sum_{e \in cp} y_e >= |cp| - 1 cp \in CP clique-path constraints
+ * \sum_{e \in cs} y_e >= |cs| - 1 cs \in CP clique-star constraints
*
- * y_ij \in N, w_ij \in R^+
+ * x_nc, y_ij \in N, w_ij \in R^+
*/
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#ifdef WITH_ILP
+
+#include <bitset.h>
+#include "pdeq.h"
+
+#include "irtools.h"
+#include "irgwalk.h"
#include "becopyilp_t.h"
+#include "beifg_t.h"
+#include "besched_t.h"
+
+#define DEBUG_LVL 1
+
+typedef struct _local_env_t {
+ firm_dbg_module_t *dbg;
+ double time_limit;
+ int first_x_var, last_x_var;
+ pmap *nr_2_irn;
+} local_env_t;
+
+static void build_coloring_cstr(ilp_env_t *ienv) {
+ be_ifg_t *ifg = ienv->co->cenv->ifg;
+ void *iter = be_ifg_nodes_iter_alloca(ifg);
+ bitset_t *colors;
+ ir_node *irn;
+ char buf[16];
+
+ colors = bitset_alloca(arch_register_class_n_regs(ienv->co->cls));
+
+ be_ifg_foreach_node(ifg, iter, irn)
+ if (!sr_is_removed(ienv->sr, irn)) {
+ int col, cst_idx;
+ arch_register_req_t req;
+ int curr_node_color = get_irn_col(ienv->co, irn);
+ int node_nr = (int)get_irn_node_nr(irn);
+ local_env_t *lenv = ienv->env;
+
+ pmap_insert(lenv->nr_2_irn, INT_TO_PTR(node_nr), irn);
+
+ arch_get_register_req(ienv->co->aenv, &req, irn, -1);
+
+ /* get assignable colors */
+ if (arch_register_req_is(&req, limited))
+ req.limited(req.limited_env, colors);
+ else
+ arch_put_non_ignore_regs(ienv->co->aenv, req.cls, colors);
+
+ /* add the coloring constraint */
+ cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 1.0);
+
+ bitset_foreach(colors, col) {
+ int var_idx = lpp_add_var(ienv->lp, name_cdd(buf, 'x', node_nr, col), lpp_binary, 0.0);
+ lpp_set_start_value(ienv->lp, var_idx, (col == curr_node_color) ? 1.0 : 0.0);
+ lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
+
+ lenv->last_x_var = var_idx;
+ if (lenv->first_x_var == -1)
+ lenv->first_x_var = var_idx;
+ }
+
+ /* add register constraint constraints */
+ bitset_foreach_clear(colors, col) {
+ int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_equal, 0.0);
+ int var_idx = lpp_add_var(ienv->lp, name_cdd(buf, 'x', node_nr, col), lpp_binary, 0.0);
+ lpp_set_start_value(ienv->lp, var_idx, 0.0);
+ lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1);
+
+ lenv->last_x_var = var_idx;
+ }
+ }
+}
+
+static void build_interference_cstr(ilp_env_t *ienv) {
+ lpp_t *lpp = ienv->lp;
+ be_ifg_t *ifg = ienv->co->cenv->ifg;
+ int n_colors = arch_register_class_n_regs(ienv->co->cls);
+ int i, col;
+
+ void *iter = be_ifg_cliques_iter_alloca(ifg);
+ ir_node **clique = alloca(sizeof(*clique) * n_colors);
+ int size;
+
+ char buf[16];
+
+ /* for each maximal clique */
+ be_ifg_foreach_clique(ifg, iter, clique, &size) {
+ int realsize = 0;
+
+ for (i=0; i<size; ++i)
+ if (!sr_is_removed(ienv->sr, clique[i]))
+ ++realsize;
+
+ if (realsize < 2)
+ continue;
+
+ /* for all colors */
+ for (col=0; col<n_colors; ++col) {
+ int cst_idx = lpp_add_cst(lpp, NULL, lpp_less, 1.0);
+
+ /* for each member of this clique */
+ for (i=0; i<size; ++i) {
+ ir_node *irn = clique[i];
+
+ if (!sr_is_removed(ienv->sr, irn)) {
+ int var_idx = lpp_get_var_idx(lpp, name_cdd(buf, 'x', (int)get_irn_node_nr(irn), col));
+ lpp_set_factor_fast(lpp, cst_idx, var_idx, 1);
+ }
+ }
+ }
+ }
+}
+
+static void build_affinity_cstr(ilp_env_t *ienv) {
+ unit_t *curr;
+ int n_colors = arch_register_class_n_regs(ienv->co->cls);
+
+ /* for all optimization units */
+ list_for_each_entry(unit_t, curr, &ienv->co->units, units) {
+ ir_node *root, *arg;
+ int root_nr, arg_nr, i, col, y_idx, root_idx, arg_idx;
+ char buf[16];
+ int root_col, arg_col;
+
+ root = curr->nodes[0];
+ root_nr = (int) get_irn_node_nr(root);
+ root_col = get_irn_col(ienv->co, root);
+
+ for (i = 1; i < curr->node_count; ++i) {
+ arg = curr->nodes[i];
+ arg_nr = (int) get_irn_node_nr(arg);
+ arg_col = get_irn_col(ienv->co, arg);
+
+ /* add a new affinity variable */
+ y_idx = lpp_add_var(ienv->lp, name_cdd_sorted(buf, 'y', root_nr, arg_nr), lpp_binary, curr->costs[i]);
+ lpp_set_start_value(ienv->lp, y_idx, (root_col==arg_col) ? 0.0 : 1.0);
+
+ /* add constraints relating the affinity var to the color vars */
+ for (col=0; col<n_colors; ++col) {
+ int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_less, 0.0);
+ root_idx = lpp_get_var_idx(ienv->lp, name_cdd(buf, 'x', root_nr, col));
+ arg_idx = lpp_get_var_idx(ienv->lp, name_cdd(buf, 'x', arg_nr, col));
+
+ lpp_set_factor_fast(ienv->lp, cst_idx, root_idx, 1.0);
+ lpp_set_factor_fast(ienv->lp, cst_idx, arg_idx, -1.0);
+ lpp_set_factor_fast(ienv->lp, cst_idx, y_idx, -1.0);
+ }
+ }
+ }
+}
+
+/**
+ * Helping stuff for build_clique_star_cstr
+ */
+typedef struct _edge_t {
+ ir_node *n1, *n2;
+} edge_t;
+
+static int compare_edge_t(const void *k1, const void *k2, size_t size) {
+ const edge_t *e1 = k1;
+ const edge_t *e2 = k2;
+
+ return ! (e1->n1 == e2->n1 && e1->n2 == e2->n2);
+}
+
+#define HASH_EDGE(e) (HASH_PTR((e)->n1) ^ HASH_PTR((e)->n2))
+
+static INLINE edge_t *add_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
+ edge_t new_edge;
+
+ if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+ new_edge.n1 = n1;
+ new_edge.n2 = n2;
+ } else {
+ new_edge.n1 = n2;
+ new_edge.n2 = n1;
+ }
+ (*counter)++;
+ return set_insert(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+}
+
+static INLINE edge_t *find_edge(set *edges, ir_node *n1, ir_node *n2) {
+ edge_t new_edge;
+
+ if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+ new_edge.n1 = n1;
+ new_edge.n2 = n2;
+ } else {
+ new_edge.n1 = n2;
+ new_edge.n2 = n1;
+ }
+ return set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+}
+
+static INLINE void remove_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
+ edge_t new_edge, *e;
+
+ if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+ new_edge.n1 = n1;
+ new_edge.n2 = n2;
+ } else {
+ new_edge.n1 = n2;
+ new_edge.n2 = n1;
+ }
+ e = set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+ if (e) {
+ e->n1 = NULL;
+ e->n2 = NULL;
+ (*counter)--;
+ }
+}
+
+#define pset_foreach(pset, irn) for(irn=pset_first(pset); irn; irn=pset_next(pset))
+
+/**
+ * Search for an interference clique and an external node
+ * with affinity edges to all nodes of the clique.
+ * At most 1 node of the clique can be colored equally with the external node.
+ */
+static void build_clique_star_cstr(ilp_env_t *ienv) {
+ affinity_t *aff;
+
+ /* for each node with affinity edges */
+ co_gs_foreach_aff_node(ienv->co, aff) {
+ struct obstack ob;
+ neighb_t *nbr;
+ ir_node *center = aff->irn;
+ ir_node **nodes;
+ set *edges;
+ int i, o, n_nodes, n_edges;
+
+ obstack_init(&ob);
+ edges = new_set(compare_edge_t, 8);
+
+ /* get all affinity neighbours */
+ n_nodes = 0;
+ co_gs_foreach_neighb(aff, nbr) {
+ obstack_ptr_grow(&ob, nbr->irn);
+ ++n_nodes;
+ }
+ nodes = obstack_finish(&ob);
+
+ /* get all interference edges between these */
+ n_edges = 0;
+ for (i=0; i<n_nodes; ++i)
+ for (o=0; o<i; ++o)
+ if (be_ifg_connected(ienv->co->cenv->ifg, nodes[i], nodes[o]))
+ add_edge(edges, nodes[i], nodes[o], &n_edges);
+
+ /* cover all these interference edges with maximal cliques */
+ while (n_edges) {
+ edge_t *e;
+ pset *clique = pset_new_ptr(8);
+ int growed;
+
+ /* get 2 starting nodes to form a clique */
+ for (e=set_first(edges); !e->n1; e=set_next(edges))
+ /*nothing*/ ;
+
+ pset_insert_ptr(clique, e->n1);
+ pset_insert_ptr(clique, e->n2);
+ remove_edge(edges, e->n1, e->n2, &n_edges);
+
+ /* while the clique is growing */
+ do {
+ growed = 0;
+
+ /* search for a candidate to extend the clique */
+ for (i=0; i<n_nodes; ++i) {
+ ir_node *member, *cand = nodes[i];
+ int is_cand;
+
+ /* if its already in the clique try the next */
+ if (pset_find_ptr(clique, cand))
+ continue;
+
+ /* are there all necessary interferences? */
+ is_cand = 1;
+ pset_foreach(clique, member) {
+ if (!find_edge(edges, cand, member)) {
+ is_cand = 0;
+ pset_break(clique);
+ break;
+ }
+ }
+
+ /* now we know if we have a clique extender */
+ if (is_cand) {
+ /* first remove all covered edges */
+ pset_foreach(clique, member)
+ remove_edge(edges, cand, member, &n_edges);
+
+ /* insert into clique */
+ pset_insert_ptr(clique, cand);
+ growed = 1;
+ break;
+ }
+ }
+ } while (growed);
+
+ /* now the clique is maximal. Finally add the constraint */
+ {
+ ir_node *member;
+ int var_idx, cst_idx, center_nr, member_nr;
+ char buf[16];
+
+ cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater, pset_count(clique)-1);
+ center_nr = get_irn_node_nr(center);
+
+ pset_foreach(clique, member) {
+ member_nr = get_irn_node_nr(member);
+ var_idx = lpp_get_var_idx(ienv->lp, name_cdd_sorted(buf, 'y', center_nr, member_nr));
+ lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
+ }
+ }
+
+ del_pset(clique);
+ }
+
+ del_set(edges);
+ obstack_free(&ob, NULL);
+ }
+}
+
+
+static void extend_path(ilp_env_t *ienv, pdeq *path, ir_node *irn) {
+ be_ifg_t *ifg = ienv->co->cenv->ifg;
+ int i, len;
+ ir_node **curr_path;
+ affinity_t *aff;
+ neighb_t *nbr;
+
+ /* do not walk backwards or in circles */
+ if (pdeq_contains(path, irn))
+ return;
+
+ /* insert the new irn */
+ pdeq_putr(path, irn);
+
+
+
+ /* check for forbidden interferences */
+ len = pdeq_len(path);
+ curr_path = alloca(len * sizeof(*curr_path));
+ pdeq_copyl(path, curr_path);
+
+ for (i=1; i<len; ++i)
+ if (be_ifg_connected(ifg, irn, curr_path[i]))
+ goto end;
+
+
+
+ /* check for terminating interference */
+ if (be_ifg_connected(ifg, irn, curr_path[0])) {
+
+ /* One node is not a path. */
+ /* And a path of length 2 is covered by a clique star constraint. */
+ if (len > 2) {
+ /* finally build the constraint */
+ int cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater, 1.0);
+ for (i=1; i<len; ++i) {
+ char buf[16];
+ int nr_1 = get_irn_node_nr(curr_path[i-1]);
+ int nr_2 = get_irn_node_nr(curr_path[i]);
+ int var_idx = lpp_get_var_idx(ienv->lp, name_cdd_sorted(buf, 'y', nr_1, nr_2));
+ lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
+ }
+ }
+
+ /* this path cannot be extended anymore */
+ goto end;
+ }
+
+
+
+ /* recursively extend the path */
+ aff = get_affinity_info(ienv->co, irn);
+ co_gs_foreach_neighb(aff, nbr)
+ extend_path(ienv, path, nbr->irn);
+
+
+end:
+ /* remove the irn */
+ pdeq_getr(path);
+
+}
+
+/**
+ * Search a path of affinity edges, whose ends are connected
+ * by an interference edge and there are no other interference
+ * edges in between.
+ * Then at least one of these affinity edges must break.
+ */
+static void build_path_cstr(ilp_env_t *ienv) {
+ affinity_t *aff_info;
+
+ /* for each node with affinity edges */
+ co_gs_foreach_aff_node(ienv->co, aff_info) {
+ pdeq *path = new_pdeq();
+
+ extend_path(ienv, path, aff_info->irn);
+
+ del_pdeq(path);
+ }
+}
+
+static void ilp2_build(ilp_env_t *ienv) {
+ local_env_t *lenv = ienv->env;
+ int lower_bound;
+
+ ienv->lp = new_lpp(ienv->co->name, lpp_minimize);
+ build_coloring_cstr(ienv);
+ build_interference_cstr(ienv);
+ build_affinity_cstr(ienv);
+ build_clique_star_cstr(ienv);
+ build_path_cstr(ienv);
+
+ lower_bound = co_get_lower_bound(ienv->co) - co_get_inevit_copy_costs(ienv->co);
+ lpp_set_bound(ienv->lp, lower_bound);
+ lpp_set_time_limit(ienv->lp, lenv->time_limit);
+}
+
+static void ilp2_apply(ilp_env_t *ienv) {
+ local_env_t *lenv = ienv->env;
+ double *sol;
+ lpp_sol_state_t state;
+ int i, count;
+
+ /* first check if there was sth. to optimize */
+ if (lenv->first_x_var >= 0) {
+
+ count = lenv->last_x_var - lenv->first_x_var + 1;
+ sol = xmalloc(count * sizeof(sol[0]));
+ state = lpp_get_solution(ienv->lp, sol, lenv->first_x_var, lenv->last_x_var);
+ if (state != lpp_optimal) {
+ printf("WARNING %s: Solution state is not 'optimal': %d\n", ienv->co->name, state);
+ assert(state >= lpp_feasible && "The solution should at least be feasible!");
+ }
+
+ for (i=0; i<count; ++i) {
+ int nodenr, color;
+ char var_name[16];
+
+ if (sol[i] > 1-EPSILON) { /* split variable name into components */
+ lpp_get_var_name(ienv->lp, lenv->first_x_var+i, var_name, sizeof(var_name));
+
+ if (sscanf(var_name, "x_%d_%d", &nodenr, &color) == 2) {
+ ir_node *irn = pmap_get(lenv->nr_2_irn, INT_TO_PTR(nodenr));
+ assert(irn && "This node number must be present in the map");
+
+ set_irn_col(ienv->co, irn, color);
+ } else
+ assert(0 && "This should be a x-var");
+ }
+ }
+ }
+
+#ifdef COPYOPT_STAT
+ /* TODO adapt to multiple possible ILPs */
+ copystat_add_ilp_time((int)(1000.0*lpp_get_sol_time(pi->curr_lp))); //now we have ms
+ copystat_add_ilp_vars(lpp_get_var_count(pi->curr_lp));
+ copystat_add_ilp_csts(lpp_get_cst_count(pi->curr_lp));
+ copystat_add_ilp_iter(lpp_get_iter_cnt(pi->curr_lp));
+#endif
+}
int co_solve_ilp2(copy_opt_t *co, double time_limit) {
- int res = 1;
+ lpp_sol_state_t sol_state;
+ ilp_env_t *ienv;
+ local_env_t my;
+
+ my.time_limit = time_limit;
+ my.first_x_var = -1;
+ my.last_x_var = -1;
+ my.nr_2_irn = pmap_create();
+ my.dbg = firm_dbg_register("ir.be.coilp2");
+ firm_dbg_set_mask(my.dbg, DEBUG_LVL);
- return res;
+ ienv = new_ilp_env(co, ilp2_build, ilp2_apply, &my);
+
+ sol_state = ilp_go(ienv);
+
+ pmap_destroy(my.nr_2_irn);
+ free_ilp_env(ienv);
+
+ return sol_state == lpp_optimal;
}
+
+#else /* WITH_ILP */
+
+static void only_that_you_can_compile_without_WITH_ILP_defined(void) {
+}
+
+#endif /* WITH_ILP */