Fix bug where we could iterate off the end of a basic block
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6116 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index 3353725..e7f4c9f 100644
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -76,8 +76,9 @@
// into the phi node destination.
//
MachineBasicBlock::iterator AfterPHIsIt = MBB.begin();
- if (AfterPHIsIt != MBB.end())
- while ((*AfterPHIsIt)->getOpcode() == TargetInstrInfo::PHI) ++AfterPHIsIt;
+ while (AfterPHIsIt != MBB.end() &&
+ (*AfterPHIsIt)->getOpcode() == TargetInstrInfo::PHI)
+ ++AfterPHIsIt; // Skip over all of the PHI nodes...
RegInfo->copyRegToReg(MBB, AfterPHIsIt, DestReg, IncomingReg, RC);
// Update live variable information if there is any...