From: Bob Wilson <bob.wilson@apple.com>
Date: Mon, 10 May 2010 17:14:26 +0000 (+0000)
Subject: Fix PR7096.  When a block containing multiple defs is tail duplicated, the
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fde18e5eff86b5055d7ed541fa87cde5aa1ab31c;p=oota-llvm.git

Fix PR7096.  When a block containing multiple defs is tail duplicated, the
SSAUpdater for the value from the first def may see uses of undefined values,
because the later defs will not have been updated yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103407 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/MachineSSAUpdater.cpp b/lib/CodeGen/MachineSSAUpdater.cpp
index 99fb99ac3c7..84d6df25397 100644
--- a/lib/CodeGen/MachineSSAUpdater.cpp
+++ b/lib/CodeGen/MachineSSAUpdater.cpp
@@ -329,7 +329,7 @@ public:
   /// InstrIsPHI - Check if an instruction is a PHI.
   ///
   static MachineInstr *InstrIsPHI(MachineInstr *I) {
-    if (I->isPHI())
+    if (I && I->isPHI())
       return I;
     return 0;
   }