[opaque pointer types] Pass function types for runtime function calls.

Emit{Nounwind,}RuntimeCall{,OrInvoke} have been modified to take a
FunctionCallee as an argument, and CreateRuntimeFunction has been
modified to return a FunctionCallee. All callers have been updated.

Additionally, CreateBuiltinFunction is removed, as it was redundant
with CreateRuntimeFunction after some previous changes.

Differential Revision: https://reviews.llvm.org/D57668

llvm-svn: 353184
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 29d153b..0ea59d1 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -3110,7 +3110,8 @@
   llvm::Type *argTypes[] = { CGF.Int64Ty, CGF.Int64Ty, Int8Ty, Int8Ty };
   llvm::FunctionType *handlerTy =
       llvm::FunctionType::get(CGF.Int64Ty, argTypes, true);
-  llvm::Value *handler = CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName);
+  llvm::FunctionCallee handler =
+      CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName);
 
   // Sign extend the args to 64-bit, so that we can use the same handler for
   // all types of overflow.