[OpenCL] Add LangAS::opencl_private to represent private address space in AST

Currently Clang uses default address space (0) to represent private address space for OpenCL
in AST. There are two issues with this:

Multiple address spaces including private address space cannot be diagnosed.
There is no mangling for default address space. For example, if private int* is emitted as
i32 addrspace(5)* in IR. It is supposed to be mangled as PUAS5i but it is mangled as
Pi instead.

This patch attempts to represent OpenCL private address space explicitly in AST. It adds
a new enum LangAS::opencl_private and adds it to the variable types which are implicitly
private:

automatic variables without address space qualifier

function parameter

pointee type without address space qualifier (OpenCL 1.2 and below)

Differential Revision: https://reviews.llvm.org/D35082

llvm-svn: 315668

1 files changed, 1 insertions, 0 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index fa4c4805e27..1b1f2df81b9 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -707,6 +707,7 @@ static const LangAS::Map *getAddressSpaceMap(const TargetInfo &T,
       1, // opencl_global
       3, // opencl_local
       2, // opencl_constant
+      0, // opencl_private
       4, // opencl_generic
       5, // cuda_device
       6, // cuda_constant