Don't rely on the isDead() MachineOperand flag when updating LiveIntervals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175732 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index b84d9d3..5584708 100644
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -320,7 +320,9 @@
}
LiveInterval &DestLI = LIS->getInterval(DestReg);
- if (NewInstr->getOperand(0).isDead()) {
+ assert(DestLI.begin() != DestLI.end() &&
+ "PHIs should have nonempty LiveIntervals.");
+ if (DestLI.endIndex().isDead()) {
// A dead PHI's live range begins and ends at the start of the MBB, but
// the lowered copy, which will still be dead, needs to begin and end at
// the copy instruction.