Clarify a deviation from the original algorithm.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46218 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp
index ff58e79..5b80b94 100644
--- a/lib/CodeGen/StrongPHIElimination.cpp
+++ b/lib/CodeGen/StrongPHIElimination.cpp
@@ -552,7 +552,10 @@
DomForestNode* child = *CI;
// If the current node is live-out of the defining block of one of its
- // children, insert a copy for it
+ // children, insert a copy for it. NOTE: The paper actually calls for
+ // a more elaborate heuristic for determining whether to insert copies
+ // for the child or the parent. In the interest of simplicity, we're
+ // just always choosing the parent.
if (isLiveOut(DFNode->getReg(),
MRI.getVRegDef(child->getReg())->getParent(), MRI, LV)) {
// Insert copies for parent