Add OpenCL 2.0 atomic builtin functions as Clang builtin

OpenCL 2.0 atomic builtin functions have a scope argument which is ideally
represented as synchronization scope argument in LLVM atomic instructions.

Clang supports translating Clang atomic builtin functions to LLVM atomic
instructions. However it currently does not support synchronization scope
of LLVM atomic instructions. Without this, users have to use LLVM assembly
code to implement OpenCL atomic builtin functions.

This patch adds OpenCL 2.0 atomic builtin functions as Clang builtin
functions, which supports generating LLVM atomic instructions with
synchronization scope operand.

Currently only constant memory scope argument is supported. Support of
non-constant memory scope argument will be added later.

Differential Revision: https://reviews.llvm.org/D28691

llvm-svn: 310082

1 files changed, 27 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 1234143..d2fcbea 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -444,6 +444,11 @@ TargetCodeGenInfo::performAddrSpaceCast(CodeGenModule &CGM, llvm::Constant *Src,
   return llvm::ConstantExpr::getPointerCast(Src, DestTy);
 }
 
+llvm::SyncScope::ID
+TargetCodeGenInfo::getLLVMSyncScopeID(SyncScope S, llvm::LLVMContext &C) const {
+  return C.getOrInsertSyncScopeID(""); /* default sync scope */
+}
+
 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
 
 /// isEmptyField - Return true iff a the field is "empty", that is it
@@ -7430,6 +7435,8 @@ public:
   }
   unsigned getGlobalVarAddressSpace(CodeGenModule &CGM,
                                     const VarDecl *D) const override;
+  llvm::SyncScope::ID getLLVMSyncScopeID(SyncScope S,
+                                         llvm::LLVMContext &C) const override;
 };
 }
 
@@ -7539,6 +7546,26 @@ AMDGPUTargetCodeGenInfo::getGlobalVarAddressSpace(CodeGenModule &CGM,
   return DefaultGlobalAS;
 }
 
+llvm::SyncScope::ID
+AMDGPUTargetCodeGenInfo::getLLVMSyncScopeID(SyncScope S,
+                                            llvm::LLVMContext &C) const {
+  StringRef Name;
+  switch (S) {
+  case SyncScope::OpenCLWorkGroup:
+    Name = "workgroup";
+    break;
+  case SyncScope::OpenCLDevice:
+    Name = "agent";
+    break;
+  case SyncScope::OpenCLAllSVMDevices:
+    Name = "";
+    break;
+  case SyncScope::OpenCLSubGroup:
+    Name = "subgroup";
+  }
+  return C.getOrInsertSyncScopeID(Name);
+}
+
 //===----------------------------------------------------------------------===//
 // SPARC v8 ABI Implementation.
 // Based on the SPARC Compliance Definition version 2.4.1.