//===-- CGOpenMPRuntimeAMDGCN.cpp - Interface to OpenMP AMDGCN Runtimes --===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

// This provides a class for OpenMP runtime code generation specialized to

// AMDGCN targets from generalized CGOpenMPRuntimeGPU class.

//

//===----------------------------------------------------------------------===//

#include "CGOpenMPRuntimeAMDGCN.h"

#include "CGOpenMPRuntimeGPU.h"

#include "CodeGenFunction.h"

#include "clang/AST/Attr.h"

#include "clang/AST/DeclOpenMP.h"

#include "clang/AST/StmtOpenMP.h"

#include "clang/AST/StmtVisitor.h"

#include "clang/Basic/Cuda.h"

#include "llvm/ADT/SmallPtrSet.h"

#include "llvm/IR/IntrinsicsAMDGPU.h"

using namespace clang;

using namespace CodeGen;

using namespace llvm::omp;

CGOpenMPRuntimeAMDGCN::CGOpenMPRuntimeAMDGCN(CodeGenModule &CGM)

    : CGOpenMPRuntimeGPU(CGM) {

  if (!CGM.getLangOpts().OpenMPIsDevice)

    llvm_unreachable("OpenMP AMDGCN can only handle device code.");

}

llvm::Value *CGOpenMPRuntimeAMDGCN::getGPUWarpSize(CodeGenFunction &CGF) {

  CGBuilderTy &Bld = CGF.Builder;

  // return constant compile-time target-specific warp size

  unsigned WarpSize = CGF.getTarget().getGridValue(llvm::omp::GV_Warp_Size);

  return Bld.getInt32(WarpSize);

}

llvm::Value *CGOpenMPRuntimeAMDGCN::getGPUThreadID(CodeGenFunction &CGF) {

  CGBuilderTy &Bld = CGF.Builder;

  llvm::Function *F =

      CGF.CGM.getIntrinsic(llvm::Intrinsic::amdgcn_workitem_id_x);

  return Bld.CreateCall(F, llvm::None, "nvptx_tid");

}

llvm::Value *CGOpenMPRuntimeAMDGCN::getGPUNumThreads(CodeGenFunction &CGF) {

  CGBuilderTy &Bld = CGF.Builder;

  llvm::Module *M = &CGF.CGM.getModule();

  const char *LocSize = "__ockl_get_local_size";

  llvm::Function *F = M->getFunction(LocSize);

  if (!F) {

    F = llvm::Function::Create(

        llvm::FunctionType::get(CGF.Int64Ty, {CGF.Int32Ty}, false),

        llvm::GlobalVariable::ExternalLinkage, LocSize, &CGF.CGM.getModule());

  }

  return Bld.CreateTrunc(

      Bld.CreateCall(F, {Bld.getInt32(0)}, "nvptx_num_threads"), CGF.Int32Ty);

}