becopyilp: Simplify the simplicial test.

- Avoid the quite expensive be_ifg_degree().
- Check while collecting the neighbours, instead of first collecting all, then testing whether they form a clique.

diff --git a/ir/be/becopyilp.c b/ir/be/becopyilp.c
index 962fcf5..221c2bc 100644 (file)
--- a/ir/be/becopyilp.c
+++ b/ir/be/becopyilp.c
@@ -95,29 +95,29 @@ size_red_t *new_size_red(copy_opt_t *co)
  */
 static inline bool sr_is_simplicial(size_red_t *sr, const ir_node *ifn)
 {
-       be_ifg_t *ifg  = sr->co->cenv->ifg;
+       bool              res = true;
+       ir_node         **all = NEW_ARR_F(ir_node*, 0);
+       be_lv_t    *const lv  = be_get_irg_liveness(sr->co->irg);
        neighbours_iter_t iter;
-       ir_node **all  = ALLOCAN(ir_node*, be_ifg_degree(ifg, ifn));
-       int       size = 0;
-       int       i;
-       int       o;
-
-       /* get all non-removed neighbors */
-       be_ifg_foreach_neighbour(ifg, &iter, ifn, curr)
-               if (!sr_is_removed(sr, curr))
-                       all[size++] = curr;
-
-       /* check if these form a clique */
-       be_lv_t *const lv = be_get_irg_liveness(sr->co->irg);
-       for (i = 0; i < size; ++i) {
-               for (o = i + 1; o < size; ++o) {
-                       if (!be_values_interfere(lv, all[i], all[o]))
-                               return false;
+       be_ifg_foreach_neighbour(sr->co->cenv->ifg, &iter, ifn, curr) {
+               /* Only consider non-removed neighbours. */
+               if (sr_is_removed(sr, curr))
+                       continue;
+
+               /* Check whether the current node forms a clique with all previous nodes. */
+               for (size_t i = ARR_LEN(all); i-- != 0;) {
+                       if (!be_values_interfere(lv, curr, all[i])) {
+                               res = false;
+                               goto end;
+                       }
                }
+
+               ARR_APP1(ir_node*, all, curr);
        }
 
-       /* all edges exist so this is a clique */
-       return true;
+end:
+       DEL_ARR_F(all);
+       return res;
 }
 
 void sr_remove(size_red_t *sr)