Cosmetics, changed loop-costs to d^2+1.
[libfirm] / ir / be / becopyheur.c
index f215625..4659f8f 100644 (file)
@@ -208,7 +208,7 @@ static ir_node *qnode_color_irn(const qnode_t *qn, ir_node *irn, int col, const
        ir_node **confl, *cn;
        int i, irn_col;
        const be_chordal_env_t *chordal_env = qn->ou->co->chordal_env;
-       const arch_env_t *arch_env = chordal_env->arch_env;
+       const arch_env_t *arch_env = get_arch_env(qn->ou->co);
        const arch_register_class_t *cls = chordal_env->cls;
 
        DBG((dbg, LEVEL_3, "\t      %+F \tcaused col(%+F) \t%2d --> %2d\n", trigger, irn, qnode_get_new_color(qn, irn), col));
@@ -380,58 +380,82 @@ static int qnode_try_color(const qnode_t *qn) {
 /**
  * Determines a maximum weighted independent set with respect to
  * the interference and conflict edges of all nodes in a qnode.
+ * TODO: This runs in 2^n in worst case. Use a heuristic iff n>???
  */
 static INLINE void qnode_max_ind_set(qnode_t *qn, const unit_t *ou) {
-       ir_node **irns;
+       ir_node **safe, **unsafe;
+       int i, o, safe_count, safe_costs, unsafe_count, *unsafe_costs;
+       bitset_t *curr, *best;
        int max, next, pos, curr_weight, best_weight = 0;
-       bitset_t *best, *curr;
 
-       irns = alloca((ou->node_count-1) * sizeof(*irns));
-       best = bitset_alloca(ou->node_count-1);
-       curr = bitset_alloca(ou->node_count-1);
+       /* assign the nodes into two groups.
+        * safe: node has no interference, hence it is in every max stable set.
+        * unsafe: node has an interference
+        */
+       safe = alloca((ou->node_count-1) * sizeof(*safe));
+       safe_costs = 0;
+       safe_count = 0;
+       unsafe = alloca((ou->node_count-1) * sizeof(*unsafe));
+       unsafe_costs = alloca((ou->node_count-1) * sizeof(*unsafe_costs));
+       unsafe_count = 0;
+       for(i=1; i<ou->node_count; ++i) {
+               int is_safe = 1;
+               for(o=1; o<ou->node_count; ++o) {
+                       if (qnode_are_conflicting(qn, ou->nodes[i], ou->nodes[o])) {
+                               if (i!=o) {
+                                       unsafe_costs[unsafe_count] = ou->costs[i];
+                                       unsafe[unsafe_count] = ou->nodes[i];
+                                       ++unsafe_count;
+                               }
+                               is_safe = 0;
+                               break;
+                       }
+               }
+               if (is_safe) {
+                       safe_costs += ou->costs[i];
+                       safe[safe_count++] = ou->nodes[i];
+               }
+       }
+
+
+
+       /* now brute force the best set out of the unsafe nodes*/
+       best = bitset_alloca(unsafe_count);
+       curr = bitset_alloca(unsafe_count);
 
-       /* brute force the best set */
        bitset_set_all(curr);
        while ((max = bitset_popcnt(curr)) != 0) {
                /* check if curr is a stable set */
-               int i, o, is_stable_set = 1;
-
-               /* copy the irns */
-               i = 0;
+               for (i=bitset_next_set(curr, 0); i!=-1; i=bitset_next_set(curr, i+1))
+                       for (o=bitset_next_set(curr, i); o!=-1; o=bitset_next_set(curr, o+1)) /* !!!!! difference to ou_max_ind_set_costs(): NOT (curr, i+1) */
+                                       if (qnode_are_conflicting(qn, unsafe[i], unsafe[o]))
+                                               goto no_stable_set;
+
+               /* if we arrive here, we have a stable set */
+               /* compute the weigth of the stable set*/
+               curr_weight = 0;
                bitset_foreach(curr, pos)
-                       irns[i++] = ou->nodes[1+pos];
-               assert(i==max);
+                       curr_weight += unsafe_costs[pos];
 
-               for(i=0; i<max; ++i)
-                       for(o=i; o<max; ++o) /* !!!!! difference to ou_max_ind_set_costs(): NOT o=i+1 */
-                               if (qnode_are_conflicting(qn, irns[i], irns[o])) {
-                                       is_stable_set = 0;
-                                       break;
-                               }
-
-               if (is_stable_set) {
-                       /* calc current weigth */
-                       curr_weight = 0;
-                       bitset_foreach(curr, pos)
-                               curr_weight += ou->costs[1+pos];
-
-                       /* any better ? */
-                       if (curr_weight > best_weight) {
-                               best_weight = curr_weight;
-                               bitset_copy(best, curr);
-                       }
+               /* any better ? */
+               if (curr_weight > best_weight) {
+                       best_weight = curr_weight;
+                       bitset_copy(best, curr);
                }
 
+no_stable_set:
                bitset_minus1(curr);
        }
 
        /* transfer the best set into the qn */
-       qn->mis_size = bitset_popcnt(best)+1;
-       qn->mis_costs = best_weight;
-       next = 0;
-       qn->mis[next++] = ou->nodes[0]; /* the root is alwazs in a max stable set */
+       qn->mis_size = 1+safe_count+bitset_popcnt(best);
+       qn->mis_costs = safe_costs+best_weight;
+       qn->mis[0] = ou->nodes[0]; /* the root is alwazs in a max stable set */
+       next = 1;
+       for (i=0; i<safe_count; ++i)
+               qn->mis[next++] = safe[i];
        bitset_foreach(best, pos)
-               qn->mis[next++] = ou->nodes[1+pos];
+               qn->mis[next++] = unsafe[pos];
 }
 
 /**
@@ -501,7 +525,7 @@ static void ou_optimize(unit_t *ou) {
 
        /* init queue */
        INIT_LIST_HEAD(&ou->queue);
-       arch_get_allocatable_regs(ou->co->chordal_env->arch_env, ou->nodes[0], arch_pos_make_out(0), ou->co->chordal_env->cls, pos_regs);
+       arch_get_allocatable_regs(get_arch_env(ou->co), ou->nodes[0], arch_pos_make_out(0), ou->co->chordal_env->cls, pos_regs);
        bitset_foreach(pos_regs, i)
                ou_insert_qnode(ou, new_qnode(ou, i));
 
@@ -524,7 +548,7 @@ static void ou_optimize(unit_t *ou) {
        /* apply the best found qnode */
        if (curr->mis_size >= 2) {
                node_stat_t *ns;
-               DBG((dbg, LEVEL_1, "\t  Best color: %d  Costs: %d/%d\n", curr->color, ou->complete_costs - curr->mis_costs, ou->complete_costs));
+               DBG((dbg, LEVEL_1, "\t  Best color: %d  Costs: %d << %d << %d\n", curr->color, ou->min_nodes_costs, ou->all_nodes_costs - curr->mis_costs, ou->all_nodes_costs));
                /* globally pin root and all args which have the same color */
                pset_insert_ptr(pinned_global, ou->nodes[0]);
                for (i=1; i<ou->node_count; ++i) {