Add member template 'Type::getAs<T>', which converts a Type* to a respective T*.
This method is intended to eventually replace the individual
Type::getAsXXXType<> methods.

The motivation behind this change is twofold:

1) Reduce redundant implementations of Type::getAsXXXType() methods. Most of
them are basically copy-and-paste.

2) By centralizing the implementation of the getAs<Type> logic we can more
smoothly move over to Doug Gregor's proposed canonical type smart pointer
scheme.

Along with this patch:

a) Removed 'Type::getAsPointerType()'; now clients use getAs<PointerType>.
b) Removed 'Type::getAsBlockPointerTypE()'; now clients use getAs<BlockPointerType>.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@76098 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaLookup.cpp b/lib/Sema/SemaLookup.cpp
index c88321e..a37be68 100644
--- a/lib/Sema/SemaLookup.cpp
+++ b/lib/Sema/SemaLookup.cpp
@@ -1435,7 +1435,7 @@
   // We handle this by unwrapping pointer and array types immediately,
   // to avoid unnecessary recursion.
   while (true) {
-    if (const PointerType *Ptr = T->getAsPointerType())
+    if (const PointerType *Ptr = T->getAs<PointerType>())
       T = Ptr->getPointeeType();
     else if (const ArrayType *Ptr = Context.getAsArrayType(T))
       T = Ptr->getElementType();