heur4: Avoid unnecessary bitset operations when the node is not limited.

diff --git a/ir/be/becopyheur4.c b/ir/be/becopyheur4.c
index 5e50150..264be4d 100644 (file)
--- a/ir/be/becopyheur4.c
+++ b/ir/be/becopyheur4.c
@@ -173,13 +173,12 @@ static co_mst_irn_t *co_mst_irn_init(co_mst_env_t *env, const ir_node *irn)
        req = arch_get_irn_register_req(irn);
        if (arch_register_req_is(req, limited)) {
                rbitset_copy_to_bitset(req->limited, res->adm_colors);
+               /* exclude global ignore registers as well */
+               bitset_and(res->adm_colors, env->allocatable_regs);
        } else {
-               bitset_set_all(res->adm_colors);
+               bitset_copy(res->adm_colors, env->allocatable_regs);
        }
 
-       /* exclude global ignore registers as well */
-       bitset_and(res->adm_colors, env->allocatable_regs);
-
        /* compute the constraint factor */
        res->constr_factor = (real_t) (1 + env->n_regs - bitset_popcount(res->adm_colors)) / env->n_regs;