Index: lib/Target/AMDGPU/SIMachineScheduler.cpp
===================================================================
--- lib/Target/AMDGPU/SIMachineScheduler.cpp
+++ lib/Target/AMDGPU/SIMachineScheduler.cpp
@@ -1119,12 +1119,11 @@
 static MachineBasicBlock::iterator
 nextIfDebug(MachineBasicBlock::iterator I,
             MachineBasicBlock::const_iterator End) {
-  // Cast the return value to nonconst MachineInstr, then cast to an
-  // instr_iterator, which does not check for null, finally return a
-  // bundle_iterator.
-  return MachineBasicBlock::instr_iterator(
-    const_cast<MachineInstr*>(
-      &*nextIfDebug(MachineBasicBlock::const_iterator(I), End)));
+  for (; I != End; ++I) {
+    if (!I->isDebugValue())
+      break;
+  }
+  return I;
 }

 void SIScheduleBlockCreator::topologicalSort() {