diff --git a/llvm/lib/Target/ARM/ARMBlockPlacement.cpp b/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
--- a/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
+++ b/llvm/lib/Target/ARM/ARMBlockPlacement.cpp
@@ -58,6 +58,8 @@
                 false)
 
 bool ARMBlockPlacement::runOnMachineFunction(MachineFunction &MF) {
+  if (skipFunction(MF.getFunction()))
+      return false;
   const ARMSubtarget &ST = static_cast<const ARMSubtarget &>(MF.getSubtarget());
   if (!ST.hasLOB())
     return false;
diff --git a/llvm/lib/Target/ARM/ARMTargetMachine.cpp b/llvm/lib/Target/ARM/ARMTargetMachine.cpp
--- a/llvm/lib/Target/ARM/ARMTargetMachine.cpp
+++ b/llvm/lib/Target/ARM/ARMTargetMachine.cpp
@@ -553,11 +553,11 @@
     return MF.getSubtarget<ARMSubtarget>().isThumb2();
   }));
 
-  addPass(createARMBlockPlacementPass());
-
-  // Don't optimize barriers at -O0.
-  if (getOptLevel() != CodeGenOpt::None)
+  // Don't optimize barriers or block placement at -O0.
+  if (getOptLevel() != CodeGenOpt::None) {
+    addPass(createARMBlockPlacementPass());
     addPass(createARMOptimizeBarriersPass());
+  }
 }
 
 void ARMPassConfig::addPreEmitPass2() {