InstrEmitter: Set kill flag when creating a cross-class copy

1 files changed, 13 insertions, 11 deletions

diff --git a/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
index a65f33e1777..14647eb57f5 100644
--- a/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
+++ b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
@@ -325,6 +325,18 @@ InstrEmitter::AddRegisterOperand(MachineInstrBuilder &MIB,
   bool isOptDef = IIOpNum < MCID.getNumOperands() &&
     MCID.OpInfo[IIOpNum].isOptionalDef();
 
+  // If this value has only one use, that use is a kill. This is a
+  // conservative approximation. InstrEmitter does trivial coalescing
+  // with CopyFromReg nodes, so don't emit kill flags for them.
+  // Avoid kill flags on Schedule cloned nodes, since there will be
+  // multiple uses.
+  // Tied operands are never killed, so we need to check that. And that
+  // means we need to determine the index of the operand.
+  bool isKill = Op.hasOneUse() &&
+                Op.getNode()->getOpcode() != ISD::CopyFromReg &&
+                !IsDebug &&
+                !(IsClone || IsCloned);
+
   // If the instruction requires a register in a different class, create
   // a new virtual register and copy the value into it, but first attempt to
   // shrink VReg's register class within reason.  For example, if VReg == GR32
@@ -338,20 +350,10 @@ InstrEmitter::AddRegisterOperand(MachineInstrBuilder &MIB,
       BuildMI(*MBB, InsertPos, Op.getNode()->getDebugLoc(),
               TII->get(TargetOpcode::COPY), NewVReg).addReg(VReg);
       VReg = NewVReg;
+      isKill = true;
     }
   }
 
-  // If this value has only one use, that use is a kill. This is a
-  // conservative approximation. InstrEmitter does trivial coalescing
-  // with CopyFromReg nodes, so don't emit kill flags for them.
-  // Avoid kill flags on Schedule cloned nodes, since there will be
-  // multiple uses.
-  // Tied operands are never killed, so we need to check that. And that
-  // means we need to determine the index of the operand.
-  bool isKill = Op.hasOneUse() &&
-                Op.getNode()->getOpcode() != ISD::CopyFromReg &&
-                !IsDebug &&
-                !(IsClone || IsCloned);
   if (isKill) {
     unsigned Idx = MIB->getNumOperands();
     while (Idx > 0 &&