cyclegraph: mergeNodes(): return early if we violate RMW

To be consistent, and to prevent unecessary merging work, we should
simply return from the mergeNodes() function as soon as we know it has
failed.

diff --git a/cyclegraph.cc b/cyclegraph.cc
index b13837293c665e9eacc4a4440e91631770c22347..89fc36ccb643c812b410deff933dc91b0ac794cc 100644 (file)
--- a/cyclegraph.cc
+++ b/cyclegraph.cc
@@ -147,8 +147,10 @@ bool CycleGraph::mergeNodes(CycleNode *w_node, CycleNode *p_node,
 
        /* Transfer the RMW */
        CycleNode *promise_rmw = p_node->getRMW();
-       if (promise_rmw && promise_rmw != w_node->getRMW() && w_node->setRMW(promise_rmw))
+       if (promise_rmw && promise_rmw != w_node->getRMW() && w_node->setRMW(promise_rmw)) {
                hasCycles = true;
+               return false;
+       }
 
        /* Transfer back edges to w_node */
        while (p_node->getNumBackEdges() > 0) {