Add ASTContext::getBaseElementType and use it in CodeGenFunction::EmitArraySubscriptExpr.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61303 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index 3bf6b2f..18ccb27 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -712,12 +712,7 @@
     
     Idx = Builder.CreateMul(Idx, VLASize);
     
-    QualType BaseType = VAT->getElementType();
-    
-    // Divide by the element size.
-    while (const VariableArrayType *AT = 
-           getContext().getAsVariableArrayType(BaseType))
-      BaseType = AT->getElementType();
+    QualType BaseType = getContext().getBaseElementType(VAT);
   
     uint64_t BaseTypeSize = getContext().getTypeSize(BaseType) / 8;
     Idx = Builder.CreateUDiv(Idx,