Index: lib/Target/AArch64/AArch64ConditionOptimizer.cpp
===================================================================
--- lib/Target/AArch64/AArch64ConditionOptimizer.cpp
+++ lib/Target/AArch64/AArch64ConditionOptimizer.cpp
@@ -62,6 +62,7 @@
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
@@ -125,6 +126,8 @@
 void AArch64ConditionOptimizer::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<MachineDominatorTree>();
   AU.addPreserved<MachineDominatorTree>();
+  AU.addRequired<LiveIntervals>();
+  AU.addPreserved<LiveIntervals>();
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
@@ -153,7 +156,9 @@
     // cmn is an alias for adds with a dead destination register.
     case AArch64::ADDSWri:
     case AArch64::ADDSXri:
-      return I;
+      if (I->getOperand(0).isDead()) return I;
+      DEBUG(dbgs() << "Destination of cmp is not dead, " << *I << '\n');
+      return nullptr;
 
     case AArch64::SUBSWrr:
     case AArch64::SUBSXrr: