Don't crash if computing a mapping to a node with zero size
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20595 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index a73a942..a94e083 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -2075,6 +2075,8 @@
// mapping the edges together now.
int N2Idx = NH2.getOffset()-NH1.getOffset();
unsigned N2Size = N2->getSize();
+ if (N2Size == 0) return; // No edges to map to.
+
for (unsigned i = 0, e = N1->getSize(); i < e; i += DS::PointerSize)
if (unsigned(N2Idx)+i < N2Size)
computeNodeMapping(N1->getLink(i), N2->getLink(N2Idx+i), NodeMap);