From b7f17d435f54b385dafbfe32f9482dde97d20a67 Mon Sep 17 00:00:00 2001
From: Matt Pharr <matt.pharr@intel.com>
Date: Fri, 27 Jan 2012 12:59:18 -0800
Subject: [PATCH] Fix crash in gather/scatter optimization pass.

---
 opt.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/opt.cpp b/opt.cpp
index 16401ba9..b4570235 100644
--- a/opt.cpp
+++ b/opt.cpp
@@ -2200,8 +2200,12 @@ lCheckMulForLinear(llvm::Value *op0, llvm::Value *op1, int vectorLength,
     llvm::ConstantVector *cv = llvm::dyn_cast<llvm::ConstantVector>(op0);
     if (cv == NULL)
         return false;
-    llvm::ConstantInt *splat = 
-        llvm::dyn_cast<llvm::ConstantInt>(cv->getSplatValue());
+
+    llvm::Constant *csplat = cv->getSplatValue();
+    if (csplat == NULL)
+        return false;
+
+    llvm::ConstantInt *splat = llvm::dyn_cast<llvm::ConstantInt>(csplat);
     if (splat == NULL)
         return false;