+ * There are 2 possibilities to spill a phi node: Only it's value, or replacing
+ * the whole phi-node with a memory phi. Normally only the value of a phi will
+ * be spilled unless you mark the phi with be_spill_phi.
+ * (Remember that each phi needs a register, so you have to spill phis when
+ * there are more phis than registers in a block)
+ */
+void be_spill_phi(spill_env_t *env, ir_node *node);
+
+/**
+ * Returns the estimated costs if a node would get reloaded at a specific place
+ * This usually returns the cost of spill + reload operation. But might return
+ * smaller values if the value has already been spilled in a former run or
+ * when it is possible to rematerialize the value.