+ invocations of NODE (represented as count in cgraph_node).
+
+ FIXME: This code is wrong. Since the callers can be also clones and
+ the clones are not scaled yet, the sums gets unrealistically high.
+ To properly compute the counts, we would need to do propagation across
+ callgraph (as external call to A might imply call to non-clonned B
+ if A's clone calls clonned B). */