[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, 3 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 75a135031e5..c8d69badb02 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -956,7 +956,9 @@ void CodeGenFunction::EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr) {
 CodeGenFunction::AutoVarEmission
 CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
   QualType Ty = D.getType();
-  assert(Ty.getAddressSpace() == LangAS::Default);
+  assert(
+      Ty.getAddressSpace() == LangAS::Default ||
+      (Ty.getAddressSpace() == LangAS::opencl_private && getLangOpts().OpenCL));
 
   AutoVarEmission emission(D);