values may die at every use

[libfirm] / ir / be / belive.c

diff --git a/ir/be/belive.c b/ir/be/belive.c
index 7581354..e6b5e71 100644 (file)
--- a/ir/be/belive.c
+++ b/ir/be/belive.c
@@ -307,6 +307,9 @@ pset *be_liveness_transfer(const arch_env_t *arch_env, const arch_register_class
                        DBG((dbg, LEVEL_1, "\tlive: %+F\n", x));
        )
 
+       /* You should better break out of your loop when hitting the first phi function. */
+       assert(!is_Phi(irn) && "liveness_transfer produces invalid results for phi nodes");
+
        if(arch_irn_consider_in_reg_alloc(arch_env, cls, irn)) {
                ir_node *del = pset_remove_ptr(live, irn);
                assert(irn == del);