pset_insert((pset *)callee->callers, irg, HASH_PTR(irg));
found = pset_find((pset *)irg->callees, &buf, HASH_PTR(callee));
if (found) { /* add Call node to list, compute new nesting. */
pset_insert((pset *)callee->callers, irg, HASH_PTR(irg));
found = pset_find((pset *)irg->callees, &buf, HASH_PTR(callee));
if (found) { /* add Call node to list, compute new nesting. */