Merging r200028:

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r200028 | benny.kra | 2014-01-24 14:02:37 -0500 (Fri, 24 Jan 2014) | 4 lines

InstCombine: Don't try to use aggregate elements of ConstantExprs.

PR18600.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_34@206054 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 5 deletions

diff --git a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
index 1e72410699..30290ee7a7 100644
--- a/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
+++ b/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
@@ -25,11 +25,13 @@ static bool CheapToScalarize(Value *V, bool isConstant) {
     if (isConstant) return true;
 
     // If all elts are the same, we can extract it and use any of the values.
-    Constant *Op0 = C->getAggregateElement(0U);
-    for (unsigned i = 1, e = V->getType()->getVectorNumElements(); i != e; ++i)
-      if (C->getAggregateElement(i) != Op0)
-        return false;
-    return true;
+    if (Constant *Op0 = C->getAggregateElement(0U)) {
+      for (unsigned i = 1, e = V->getType()->getVectorNumElements(); i != e;
+           ++i)
+        if (C->getAggregateElement(i) != Op0)
+          return false;
+      return true;
+    }
   }
   Instruction *I = dyn_cast<Instruction>(V);
   if (!I) return false;