From 6cc1aeaad23b878fbf252efc3e45fb3a74a646eb Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Sat, 6 Mar 2010 01:14:19 +0000
Subject: [PATCH] Don't update physical register def.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97861 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/MachineCSE.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/CodeGen/MachineCSE.cpp b/lib/CodeGen/MachineCSE.cpp
index af35a7a3bb3..b376e3d05fe 100644
--- a/lib/CodeGen/MachineCSE.cpp
+++ b/lib/CodeGen/MachineCSE.cpp
@@ -238,8 +238,9 @@ bool MachineCSE::ProcessBlock(MachineDomTreeNode *Node) {
         continue;
       unsigned OldReg = MO.getReg();
       unsigned NewReg = CSMI->getOperand(i).getReg();
-      assert(OldReg != NewReg &&
-             TargetRegisterInfo::isVirtualRegister(OldReg) &&
+      if (OldReg == NewReg)
+        continue;
+      assert(TargetRegisterInfo::isVirtualRegister(OldReg) &&
              TargetRegisterInfo::isVirtualRegister(NewReg) &&
              "Do not CSE physical register defs!");
       MRI->replaceRegWith(OldReg, NewReg);