Fix a really nasty vector miscompilation bill recently introduced.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43181 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 1ad8e80..8ffdf63 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -4150,9 +4150,9 @@
 
     if (MVT::getSizeInBits(Idx.getValueType()) >
         MVT::getSizeInBits(TLI.getPointerTy()))
-      Idx = DAG.getNode(ISD::TRUNCATE, TLI.getPointerTy(), StackPtr);
+      Idx = DAG.getNode(ISD::TRUNCATE, TLI.getPointerTy(), Idx);
     else
-      Idx = DAG.getNode(ISD::ZERO_EXTEND, TLI.getPointerTy(), StackPtr);
+      Idx = DAG.getNode(ISD::ZERO_EXTEND, TLI.getPointerTy(), Idx);
 
     StackPtr = DAG.getNode(ISD::ADD, Idx.getValueType(), Idx, StackPtr);