Import LLVM 10.0.0 release including clang, lld and lldb.

ok hackroom
tested by plenty

1 files changed, 808 insertions, 0 deletions

diff --git a/gnu/llvm/clang/lib/CodeGen/CGCUDANV.cpp b/gnu/llvm/clang/lib/CodeGen/CGCUDANV.cpp
new file mode 100644
index 00000000000..5c5cbaff025
--- /dev/null
+++ b/gnu/llvm/clang/lib/CodeGen/CGCUDANV.cpp
@@ -0,0 +1,808 @@
+//===----- CGCUDANV.cpp - Interface to NVIDIA CUDA Runtime ----------------===//
+//
+// 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 CUDA code generation targeting the NVIDIA CUDA
+// runtime library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CGCUDARuntime.h"
+#include "CodeGenFunction.h"
+#include "CodeGenModule.h"
+#include "clang/AST/Decl.h"
+#include "clang/Basic/Cuda.h"
+#include "clang/CodeGen/CodeGenABITypes.h"
+#include "clang/CodeGen/ConstantInitBuilder.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/Support/Format.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+namespace {
+constexpr unsigned CudaFatMagic = 0x466243b1;
+constexpr unsigned HIPFatMagic = 0x48495046; // "HIPF"
+
+class CGNVCUDARuntime : public CGCUDARuntime {
+
+private:
+  llvm::IntegerType *IntTy, *SizeTy;
+  llvm::Type *VoidTy;
+  llvm::PointerType *CharPtrTy, *VoidPtrTy, *VoidPtrPtrTy;
+
+  /// Convenience reference to LLVM Context
+  llvm::LLVMContext &Context;
+  /// Convenience reference to the current module
+  llvm::Module &TheModule;
+  /// Keeps track of kernel launch stubs emitted in this module
+  struct KernelInfo {
+    llvm::Function *Kernel;
+    const Decl *D;
+  };
+  llvm::SmallVector<KernelInfo, 16> EmittedKernels;
+  struct VarInfo {
+    llvm::GlobalVariable *Var;
+    const VarDecl *D;
+    unsigned Flag;
+  };
+  llvm::SmallVector<VarInfo, 16> DeviceVars;
+  /// Keeps track of variable containing handle of GPU binary. Populated by
+  /// ModuleCtorFunction() and used to create corresponding cleanup calls in
+  /// ModuleDtorFunction()
+  llvm::GlobalVariable *GpuBinaryHandle = nullptr;
+  /// Whether we generate relocatable device code.
+  bool RelocatableDeviceCode;
+  /// Mangle context for device.
+  std::unique_ptr<MangleContext> DeviceMC;
+
+  llvm::FunctionCallee getSetupArgumentFn() const;
+  llvm::FunctionCallee getLaunchFn() const;
+
+  llvm::FunctionType *getRegisterGlobalsFnTy() const;
+  llvm::FunctionType *getCallbackFnTy() const;
+  llvm::FunctionType *getRegisterLinkedBinaryFnTy() const;
+  std::string addPrefixToName(StringRef FuncName) const;
+  std::string addUnderscoredPrefixToName(StringRef FuncName) const;
+
+  /// Creates a function to register all kernel stubs generated in this module.
+  llvm::Function *makeRegisterGlobalsFn();
+
+  /// Helper function that generates a constant string and returns a pointer to
+  /// the start of the string.  The result of this function can be used anywhere
+  /// where the C code specifies const char*.
+  llvm::Constant *makeConstantString(const std::string &Str,
+                                     const std::string &Name = "",
+                                     const std::string &SectionName = "",
+                                     unsigned Alignment = 0) {
+    llvm::Constant *Zeros[] = {llvm::ConstantInt::get(SizeTy, 0),
+                               llvm::ConstantInt::get(SizeTy, 0)};
+    auto ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
+    llvm::GlobalVariable *GV =
+        cast<llvm::GlobalVariable>(ConstStr.getPointer());
+    if (!SectionName.empty()) {
+      GV->setSection(SectionName);
+      // Mark the address as used which make sure that this section isn't
+      // merged and we will really have it in the object file.
+      GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::None);
+    }
+    if (Alignment)
+      GV->setAlignment(llvm::Align(Alignment));
+
+    return llvm::ConstantExpr::getGetElementPtr(ConstStr.getElementType(),
+                                                ConstStr.getPointer(), Zeros);
+  }
+
+  /// Helper function that generates an empty dummy function returning void.
+  llvm::Function *makeDummyFunction(llvm::FunctionType *FnTy) {
+    assert(FnTy->getReturnType()->isVoidTy() &&
+           "Can only generate dummy functions returning void!");
+    llvm::Function *DummyFunc = llvm::Function::Create(
+        FnTy, llvm::GlobalValue::InternalLinkage, "dummy", &TheModule);
+
+    llvm::BasicBlock *DummyBlock =
+        llvm::BasicBlock::Create(Context, "", DummyFunc);
+    CGBuilderTy FuncBuilder(CGM, Context);
+    FuncBuilder.SetInsertPoint(DummyBlock);
+    FuncBuilder.CreateRetVoid();
+
+    return DummyFunc;
+  }
+
+  void emitDeviceStubBodyLegacy(CodeGenFunction &CGF, FunctionArgList &Args);
+  void emitDeviceStubBodyNew(CodeGenFunction &CGF, FunctionArgList &Args);
+  std::string getDeviceSideName(const Decl *ND);
+
+public:
+  CGNVCUDARuntime(CodeGenModule &CGM);
+
+  void emitDeviceStub(CodeGenFunction &CGF, FunctionArgList &Args) override;
+  void registerDeviceVar(const VarDecl *VD, llvm::GlobalVariable &Var,
+                         unsigned Flags) override {
+    DeviceVars.push_back({&Var, VD, Flags});
+  }
+
+  /// Creates module constructor function
+  llvm::Function *makeModuleCtorFunction() override;
+  /// Creates module destructor function
+  llvm::Function *makeModuleDtorFunction() override;
+  /// Construct and return the stub name of a kernel.
+  std::string getDeviceStubName(llvm::StringRef Name) const override;
+};
+
+}
+
+std::string CGNVCUDARuntime::addPrefixToName(StringRef FuncName) const {
+  if (CGM.getLangOpts().HIP)
+    return ((Twine("hip") + Twine(FuncName)).str());
+  return ((Twine("cuda") + Twine(FuncName)).str());
+}
+std::string
+CGNVCUDARuntime::addUnderscoredPrefixToName(StringRef FuncName) const {
+  if (CGM.getLangOpts().HIP)
+    return ((Twine("__hip") + Twine(FuncName)).str());
+  return ((Twine("__cuda") + Twine(FuncName)).str());
+}
+
+CGNVCUDARuntime::CGNVCUDARuntime(CodeGenModule &CGM)
+    : CGCUDARuntime(CGM), Context(CGM.getLLVMContext()),
+      TheModule(CGM.getModule()),
+      RelocatableDeviceCode(CGM.getLangOpts().GPURelocatableDeviceCode),
+      DeviceMC(CGM.getContext().createMangleContext(
+          CGM.getContext().getAuxTargetInfo())) {
+  CodeGen::CodeGenTypes &Types = CGM.getTypes();
+  ASTContext &Ctx = CGM.getContext();
+
+  IntTy = CGM.IntTy;
+  SizeTy = CGM.SizeTy;
+  VoidTy = CGM.VoidTy;
+
+  CharPtrTy = llvm::PointerType::getUnqual(Types.ConvertType(Ctx.CharTy));
+  VoidPtrTy = cast<llvm::PointerType>(Types.ConvertType(Ctx.VoidPtrTy));
+  VoidPtrPtrTy = VoidPtrTy->getPointerTo();
+}
+
+llvm::FunctionCallee CGNVCUDARuntime::getSetupArgumentFn() const {
+  // cudaError_t cudaSetupArgument(void *, size_t, size_t)
+  llvm::Type *Params[] = {VoidPtrTy, SizeTy, SizeTy};
+  return CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(IntTy, Params, false),
+      addPrefixToName("SetupArgument"));
+}
+
+llvm::FunctionCallee CGNVCUDARuntime::getLaunchFn() const {
+  if (CGM.getLangOpts().HIP) {
+    // hipError_t hipLaunchByPtr(char *);
+    return CGM.CreateRuntimeFunction(
+        llvm::FunctionType::get(IntTy, CharPtrTy, false), "hipLaunchByPtr");
+  } else {
+    // cudaError_t cudaLaunch(char *);
+    return CGM.CreateRuntimeFunction(
+        llvm::FunctionType::get(IntTy, CharPtrTy, false), "cudaLaunch");
+  }
+}
+
+llvm::FunctionType *CGNVCUDARuntime::getRegisterGlobalsFnTy() const {
+  return llvm::FunctionType::get(VoidTy, VoidPtrPtrTy, false);
+}
+
+llvm::FunctionType *CGNVCUDARuntime::getCallbackFnTy() const {
+  return llvm::FunctionType::get(VoidTy, VoidPtrTy, false);
+}
+
+llvm::FunctionType *CGNVCUDARuntime::getRegisterLinkedBinaryFnTy() const {
+  auto CallbackFnTy = getCallbackFnTy();
+  auto RegisterGlobalsFnTy = getRegisterGlobalsFnTy();
+  llvm::Type *Params[] = {RegisterGlobalsFnTy->getPointerTo(), VoidPtrTy,
+                          VoidPtrTy, CallbackFnTy->getPointerTo()};
+  return llvm::FunctionType::get(VoidTy, Params, false);
+}
+
+std::string CGNVCUDARuntime::getDeviceSideName(const Decl *D) {
+  auto *ND = cast<const NamedDecl>(D);
+  std::string DeviceSideName;
+  if (DeviceMC->shouldMangleDeclName(ND)) {
+    SmallString<256> Buffer;
+    llvm::raw_svector_ostream Out(Buffer);
+    DeviceMC->mangleName(ND, Out);
+    DeviceSideName = Out.str();
+  } else
+    DeviceSideName = ND->getIdentifier()->getName();
+  return DeviceSideName;
+}
+
+void CGNVCUDARuntime::emitDeviceStub(CodeGenFunction &CGF,
+                                     FunctionArgList &Args) {
+  // Ensure either we have different ABIs between host and device compilations,
+  // says host compilation following MSVC ABI but device compilation follows
+  // Itanium C++ ABI or, if they follow the same ABI, kernel names after
+  // mangling should be the same after name stubbing. The later checking is
+  // very important as the device kernel name being mangled in host-compilation
+  // is used to resolve the device binaries to be executed. Inconsistent naming
+  // result in undefined behavior. Even though we cannot check that naming
+  // directly between host- and device-compilations, the host- and
+  // device-mangling in host compilation could help catching certain ones.
+  assert((CGF.CGM.getContext().getAuxTargetInfo() &&
+          (CGF.CGM.getContext().getAuxTargetInfo()->getCXXABI() !=
+           CGF.CGM.getContext().getTargetInfo().getCXXABI())) ||
+         getDeviceStubName(getDeviceSideName(CGF.CurFuncDecl)) ==
+             CGF.CurFn->getName());
+
+  EmittedKernels.push_back({CGF.CurFn, CGF.CurFuncDecl});
+  if (CudaFeatureEnabled(CGM.getTarget().getSDKVersion(),
+                         CudaFeature::CUDA_USES_NEW_LAUNCH) ||
+      CGF.getLangOpts().HIPUseNewLaunchAPI)
+    emitDeviceStubBodyNew(CGF, Args);
+  else
+    emitDeviceStubBodyLegacy(CGF, Args);
+}
+
+// CUDA 9.0+ uses new way to launch kernels. Parameters are packed in a local
+// array and kernels are launched using cudaLaunchKernel().
+void CGNVCUDARuntime::emitDeviceStubBodyNew(CodeGenFunction &CGF,
+                                            FunctionArgList &Args) {
+  // Build the shadow stack entry at the very start of the function.
+
+  // Calculate amount of space we will need for all arguments.  If we have no
+  // args, allocate a single pointer so we still have a valid pointer to the
+  // argument array that we can pass to runtime, even if it will be unused.
+  Address KernelArgs = CGF.CreateTempAlloca(
+      VoidPtrTy, CharUnits::fromQuantity(16), "kernel_args",
+      llvm::ConstantInt::get(SizeTy, std::max<size_t>(1, Args.size())));
+  // Store pointers to the arguments in a locally allocated launch_args.
+  for (unsigned i = 0; i < Args.size(); ++i) {
+    llvm::Value* VarPtr = CGF.GetAddrOfLocalVar(Args[i]).getPointer();
+    llvm::Value *VoidVarPtr = CGF.Builder.CreatePointerCast(VarPtr, VoidPtrTy);
+    CGF.Builder.CreateDefaultAlignedStore(
+        VoidVarPtr, CGF.Builder.CreateConstGEP1_32(KernelArgs.getPointer(), i));
+  }
+
+  llvm::BasicBlock *EndBlock = CGF.createBasicBlock("setup.end");
+
+  // Lookup cudaLaunchKernel/hipLaunchKernel function.
+  // cudaError_t cudaLaunchKernel(const void *func, dim3 gridDim, dim3 blockDim,
+  //                              void **args, size_t sharedMem,
+  //                              cudaStream_t stream);
+  // hipError_t hipLaunchKernel(const void *func, dim3 gridDim, dim3 blockDim,
+  //                            void **args, size_t sharedMem,
+  //                            hipStream_t stream);
+  TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl();
+  DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
+  auto LaunchKernelName = addPrefixToName("LaunchKernel");
+  IdentifierInfo &cudaLaunchKernelII =
+      CGM.getContext().Idents.get(LaunchKernelName);
+  FunctionDecl *cudaLaunchKernelFD = nullptr;
+  for (const auto &Result : DC->lookup(&cudaLaunchKernelII)) {
+    if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Result))
+      cudaLaunchKernelFD = FD;
+  }
+
+  if (cudaLaunchKernelFD == nullptr) {
+    CGM.Error(CGF.CurFuncDecl->getLocation(),
+              "Can't find declaration for " + LaunchKernelName);
+    return;
+  }
+  // Create temporary dim3 grid_dim, block_dim.
+  ParmVarDecl *GridDimParam = cudaLaunchKernelFD->getParamDecl(1);
+  QualType Dim3Ty = GridDimParam->getType();
+  Address GridDim =
+      CGF.CreateMemTemp(Dim3Ty, CharUnits::fromQuantity(8), "grid_dim");
+  Address BlockDim =
+      CGF.CreateMemTemp(Dim3Ty, CharUnits::fromQuantity(8), "block_dim");
+  Address ShmemSize =
+      CGF.CreateTempAlloca(SizeTy, CGM.getSizeAlign(), "shmem_size");
+  Address Stream =
+      CGF.CreateTempAlloca(VoidPtrTy, CGM.getPointerAlign(), "stream");
+  llvm::FunctionCallee cudaPopConfigFn = CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(IntTy,
+                              {/*gridDim=*/GridDim.getType(),
+                               /*blockDim=*/BlockDim.getType(),
+                               /*ShmemSize=*/ShmemSize.getType(),
+                               /*Stream=*/Stream.getType()},
+                              /*isVarArg=*/false),
+      addUnderscoredPrefixToName("PopCallConfiguration"));
+
+  CGF.EmitRuntimeCallOrInvoke(cudaPopConfigFn,
+                              {GridDim.getPointer(), BlockDim.getPointer(),
+                               ShmemSize.getPointer(), Stream.getPointer()});
+
+  // Emit the call to cudaLaunch
+  llvm::Value *Kernel = CGF.Builder.CreatePointerCast(CGF.CurFn, VoidPtrTy);
+  CallArgList LaunchKernelArgs;
+  LaunchKernelArgs.add(RValue::get(Kernel),
+                       cudaLaunchKernelFD->getParamDecl(0)->getType());
+  LaunchKernelArgs.add(RValue::getAggregate(GridDim), Dim3Ty);
+  LaunchKernelArgs.add(RValue::getAggregate(BlockDim), Dim3Ty);
+  LaunchKernelArgs.add(RValue::get(KernelArgs.getPointer()),
+                       cudaLaunchKernelFD->getParamDecl(3)->getType());
+  LaunchKernelArgs.add(RValue::get(CGF.Builder.CreateLoad(ShmemSize)),
+                       cudaLaunchKernelFD->getParamDecl(4)->getType());
+  LaunchKernelArgs.add(RValue::get(CGF.Builder.CreateLoad(Stream)),
+                       cudaLaunchKernelFD->getParamDecl(5)->getType());
+
+  QualType QT = cudaLaunchKernelFD->getType();
+  QualType CQT = QT.getCanonicalType();
+  llvm::Type *Ty = CGM.getTypes().ConvertType(CQT);
+  llvm::FunctionType *FTy = dyn_cast<llvm::FunctionType>(Ty);
+
+  const CGFunctionInfo &FI =
+      CGM.getTypes().arrangeFunctionDeclaration(cudaLaunchKernelFD);
+  llvm::FunctionCallee cudaLaunchKernelFn =
+      CGM.CreateRuntimeFunction(FTy, LaunchKernelName);
+  CGF.EmitCall(FI, CGCallee::forDirect(cudaLaunchKernelFn), ReturnValueSlot(),
+               LaunchKernelArgs);
+  CGF.EmitBranch(EndBlock);
+
+  CGF.EmitBlock(EndBlock);
+}
+
+void CGNVCUDARuntime::emitDeviceStubBodyLegacy(CodeGenFunction &CGF,
+                                               FunctionArgList &Args) {
+  // Emit a call to cudaSetupArgument for each arg in Args.
+  llvm::FunctionCallee cudaSetupArgFn = getSetupArgumentFn();
+  llvm::BasicBlock *EndBlock = CGF.createBasicBlock("setup.end");
+  CharUnits Offset = CharUnits::Zero();
+  for (const VarDecl *A : Args) {
+    CharUnits TyWidth, TyAlign;
+    std::tie(TyWidth, TyAlign) =
+        CGM.getContext().getTypeInfoInChars(A->getType());
+    Offset = Offset.alignTo(TyAlign);
+    llvm::Value *Args[] = {
+        CGF.Builder.CreatePointerCast(CGF.GetAddrOfLocalVar(A).getPointer(),
+                                      VoidPtrTy),
+        llvm::ConstantInt::get(SizeTy, TyWidth.getQuantity()),
+        llvm::ConstantInt::get(SizeTy, Offset.getQuantity()),
+    };
+    llvm::CallBase *CB = CGF.EmitRuntimeCallOrInvoke(cudaSetupArgFn, Args);
+    llvm::Constant *Zero = llvm::ConstantInt::get(IntTy, 0);
+    llvm::Value *CBZero = CGF.Builder.CreateICmpEQ(CB, Zero);
+    llvm::BasicBlock *NextBlock = CGF.createBasicBlock("setup.next");
+    CGF.Builder.CreateCondBr(CBZero, NextBlock, EndBlock);
+    CGF.EmitBlock(NextBlock);
+    Offset += TyWidth;
+  }
+
+  // Emit the call to cudaLaunch
+  llvm::FunctionCallee cudaLaunchFn = getLaunchFn();
+  llvm::Value *Arg = CGF.Builder.CreatePointerCast(CGF.CurFn, CharPtrTy);
+  CGF.EmitRuntimeCallOrInvoke(cudaLaunchFn, Arg);
+  CGF.EmitBranch(EndBlock);
+
+  CGF.EmitBlock(EndBlock);
+}
+
+/// Creates a function that sets up state on the host side for CUDA objects that
+/// have a presence on both the host and device sides. Specifically, registers
+/// the host side of kernel functions and device global variables with the CUDA
+/// runtime.
+/// \code
+/// void __cuda_register_globals(void** GpuBinaryHandle) {
+///    __cudaRegisterFunction(GpuBinaryHandle,Kernel0,...);
+///    ...
+///    __cudaRegisterFunction(GpuBinaryHandle,KernelM,...);
+///    __cudaRegisterVar(GpuBinaryHandle, GlobalVar0, ...);
+///    ...
+///    __cudaRegisterVar(GpuBinaryHandle, GlobalVarN, ...);
+/// }
+/// \endcode
+llvm::Function *CGNVCUDARuntime::makeRegisterGlobalsFn() {
+  // No need to register anything
+  if (EmittedKernels.empty() && DeviceVars.empty())
+    return nullptr;
+
+  llvm::Function *RegisterKernelsFunc = llvm::Function::Create(
+      getRegisterGlobalsFnTy(), llvm::GlobalValue::InternalLinkage,
+      addUnderscoredPrefixToName("_register_globals"), &TheModule);
+  llvm::BasicBlock *EntryBB =
+      llvm::BasicBlock::Create(Context, "entry", RegisterKernelsFunc);
+  CGBuilderTy Builder(CGM, Context);
+  Builder.SetInsertPoint(EntryBB);
+
+  // void __cudaRegisterFunction(void **, const char *, char *, const char *,
+  //                             int, uint3*, uint3*, dim3*, dim3*, int*)
+  llvm::Type *RegisterFuncParams[] = {
+      VoidPtrPtrTy, CharPtrTy, CharPtrTy, CharPtrTy, IntTy,
+      VoidPtrTy,    VoidPtrTy, VoidPtrTy, VoidPtrTy, IntTy->getPointerTo()};
+  llvm::FunctionCallee RegisterFunc = CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(IntTy, RegisterFuncParams, false),
+      addUnderscoredPrefixToName("RegisterFunction"));
+
+  // Extract GpuBinaryHandle passed as the first argument passed to
+  // __cuda_register_globals() and generate __cudaRegisterFunction() call for
+  // each emitted kernel.
+  llvm::Argument &GpuBinaryHandlePtr = *RegisterKernelsFunc->arg_begin();
+  for (auto &&I : EmittedKernels) {
+    llvm::Constant *KernelName = makeConstantString(getDeviceSideName(I.D));
+    llvm::Constant *NullPtr = llvm::ConstantPointerNull::get(VoidPtrTy);
+    llvm::Value *Args[] = {
+        &GpuBinaryHandlePtr,
+        Builder.CreateBitCast(I.Kernel, VoidPtrTy),
+        KernelName,
+        KernelName,
+        llvm::ConstantInt::get(IntTy, -1),
+        NullPtr,
+        NullPtr,
+        NullPtr,
+        NullPtr,
+        llvm::ConstantPointerNull::get(IntTy->getPointerTo())};
+    Builder.CreateCall(RegisterFunc, Args);
+  }
+
+  // void __cudaRegisterVar(void **, char *, char *, const char *,
+  //                        int, int, int, int)
+  llvm::Type *RegisterVarParams[] = {VoidPtrPtrTy, CharPtrTy, CharPtrTy,
+                                     CharPtrTy,    IntTy,     IntTy,
+                                     IntTy,        IntTy};
+  llvm::FunctionCallee RegisterVar = CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(IntTy, RegisterVarParams, false),
+      addUnderscoredPrefixToName("RegisterVar"));
+  for (auto &&Info : DeviceVars) {
+    llvm::GlobalVariable *Var = Info.Var;
+    unsigned Flags = Info.Flag;
+    llvm::Constant *VarName = makeConstantString(getDeviceSideName(Info.D));
+    uint64_t VarSize =
+        CGM.getDataLayout().getTypeAllocSize(Var->getValueType());
+    llvm::Value *Args[] = {
+        &GpuBinaryHandlePtr,
+        Builder.CreateBitCast(Var, VoidPtrTy),
+        VarName,
+        VarName,
+        llvm::ConstantInt::get(IntTy, (Flags & ExternDeviceVar) ? 1 : 0),
+        llvm::ConstantInt::get(IntTy, VarSize),
+        llvm::ConstantInt::get(IntTy, (Flags & ConstantDeviceVar) ? 1 : 0),
+        llvm::ConstantInt::get(IntTy, 0)};
+    Builder.CreateCall(RegisterVar, Args);
+  }
+
+  Builder.CreateRetVoid();
+  return RegisterKernelsFunc;
+}
+
+/// Creates a global constructor function for the module:
+///
+/// For CUDA:
+/// \code
+/// void __cuda_module_ctor(void*) {
+///     Handle = __cudaRegisterFatBinary(GpuBinaryBlob);
+///     __cuda_register_globals(Handle);
+/// }
+/// \endcode
+///
+/// For HIP:
+/// \code
+/// void __hip_module_ctor(void*) {
+///     if (__hip_gpubin_handle == 0) {
+///         __hip_gpubin_handle  = __hipRegisterFatBinary(GpuBinaryBlob);
+///         __hip_register_globals(__hip_gpubin_handle);
+///     }
+/// }
+/// \endcode
+llvm::Function *CGNVCUDARuntime::makeModuleCtorFunction() {
+  bool IsHIP = CGM.getLangOpts().HIP;
+  bool IsCUDA = CGM.getLangOpts().CUDA;
+  // No need to generate ctors/dtors if there is no GPU binary.
+  StringRef CudaGpuBinaryFileName = CGM.getCodeGenOpts().CudaGpuBinaryFileName;
+  if (CudaGpuBinaryFileName.empty() && !IsHIP)
+    return nullptr;
+  if ((IsHIP || (IsCUDA && !RelocatableDeviceCode)) && EmittedKernels.empty() &&
+      DeviceVars.empty())
+    return nullptr;
+
+  // void __{cuda|hip}_register_globals(void* handle);
+  llvm::Function *RegisterGlobalsFunc = makeRegisterGlobalsFn();
+  // We always need a function to pass in as callback. Create a dummy
+  // implementation if we don't need to register anything.
+  if (RelocatableDeviceCode && !RegisterGlobalsFunc)
+    RegisterGlobalsFunc = makeDummyFunction(getRegisterGlobalsFnTy());
+
+  // void ** __{cuda|hip}RegisterFatBinary(void *);
+  llvm::FunctionCallee RegisterFatbinFunc = CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(VoidPtrPtrTy, VoidPtrTy, false),
+      addUnderscoredPrefixToName("RegisterFatBinary"));
+  // struct { int magic, int version, void * gpu_binary, void * dont_care };
+  llvm::StructType *FatbinWrapperTy =
+      llvm::StructType::get(IntTy, IntTy, VoidPtrTy, VoidPtrTy);
+
+  // Register GPU binary with the CUDA runtime, store returned handle in a
+  // global variable and save a reference in GpuBinaryHandle to be cleaned up
+  // in destructor on exit. Then associate all known kernels with the GPU binary
+  // handle so CUDA runtime can figure out what to call on the GPU side.
+  std::unique_ptr<llvm::MemoryBuffer> CudaGpuBinary = nullptr;
+  if (!CudaGpuBinaryFileName.empty()) {
+    llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> CudaGpuBinaryOrErr =
+        llvm::MemoryBuffer::getFileOrSTDIN(CudaGpuBinaryFileName);
+    if (std::error_code EC = CudaGpuBinaryOrErr.getError()) {
+      CGM.getDiags().Report(diag::err_cannot_open_file)
+          << CudaGpuBinaryFileName << EC.message();
+      return nullptr;
+    }
+    CudaGpuBinary = std::move(CudaGpuBinaryOrErr.get());
+  }
+
+  llvm::Function *ModuleCtorFunc = llvm::Function::Create(
+      llvm::FunctionType::get(VoidTy, VoidPtrTy, false),
+      llvm::GlobalValue::InternalLinkage,
+      addUnderscoredPrefixToName("_module_ctor"), &TheModule);
+  llvm::BasicBlock *CtorEntryBB =
+      llvm::BasicBlock::Create(Context, "entry", ModuleCtorFunc);
+  CGBuilderTy CtorBuilder(CGM, Context);
+
+  CtorBuilder.SetInsertPoint(CtorEntryBB);
+
+  const char *FatbinConstantName;
+  const char *FatbinSectionName;
+  const char *ModuleIDSectionName;
+  StringRef ModuleIDPrefix;
+  llvm::Constant *FatBinStr;
+  unsigned FatMagic;
+  if (IsHIP) {
+    FatbinConstantName = ".hip_fatbin";
+    FatbinSectionName = ".hipFatBinSegment";
+
+    ModuleIDSectionName = "__hip_module_id";
+    ModuleIDPrefix = "__hip_";
+
+    if (CudaGpuBinary) {
+      // If fatbin is available from early finalization, create a string
+      // literal containing the fat binary loaded from the given file.
+      FatBinStr = makeConstantString(CudaGpuBinary->getBuffer(), "",
+                                     FatbinConstantName, 8);
+    } else {
+      // If fatbin is not available, create an external symbol
+      // __hip_fatbin in section .hip_fatbin. The external symbol is supposed
+      // to contain the fat binary but will be populated somewhere else,
+      // e.g. by lld through link script.
+      FatBinStr = new llvm::GlobalVariable(
+        CGM.getModule(), CGM.Int8Ty,
+        /*isConstant=*/true, llvm::GlobalValue::ExternalLinkage, nullptr,
+        "__hip_fatbin", nullptr,
+        llvm::GlobalVariable::NotThreadLocal);
+      cast<llvm::GlobalVariable>(FatBinStr)->setSection(FatbinConstantName);
+    }
+
+    FatMagic = HIPFatMagic;
+  } else {
+    if (RelocatableDeviceCode)
+      FatbinConstantName = CGM.getTriple().isMacOSX()
+                               ? "__NV_CUDA,__nv_relfatbin"
+                               : "__nv_relfatbin";
+    else
+      FatbinConstantName =
+          CGM.getTriple().isMacOSX() ? "__NV_CUDA,__nv_fatbin" : ".nv_fatbin";
+    // NVIDIA's cuobjdump looks for fatbins in this section.
+    FatbinSectionName =
+        CGM.getTriple().isMacOSX() ? "__NV_CUDA,__fatbin" : ".nvFatBinSegment";
+
+    ModuleIDSectionName = CGM.getTriple().isMacOSX()
+                              ? "__NV_CUDA,__nv_module_id"
+                              : "__nv_module_id";
+    ModuleIDPrefix = "__nv_";
+
+    // For CUDA, create a string literal containing the fat binary loaded from
+    // the given file.
+    FatBinStr = makeConstantString(CudaGpuBinary->getBuffer(), "",
+                                   FatbinConstantName, 8);
+    FatMagic = CudaFatMagic;
+  }
+
+  // Create initialized wrapper structure that points to the loaded GPU binary
+  ConstantInitBuilder Builder(CGM);
+  auto Values = Builder.beginStruct(FatbinWrapperTy);
+  // Fatbin wrapper magic.
+  Values.addInt(IntTy, FatMagic);
+  // Fatbin version.
+  Values.addInt(IntTy, 1);
+  // Data.
+  Values.add(FatBinStr);
+  // Unused in fatbin v1.
+  Values.add(llvm::ConstantPointerNull::get(VoidPtrTy));
+  llvm::GlobalVariable *FatbinWrapper = Values.finishAndCreateGlobal(
+      addUnderscoredPrefixToName("_fatbin_wrapper"), CGM.getPointerAlign(),
+      /*constant*/ true);
+  FatbinWrapper->setSection(FatbinSectionName);
+
+  // There is only one HIP fat binary per linked module, however there are
+  // multiple constructor functions. Make sure the fat binary is registered
+  // only once. The constructor functions are executed by the dynamic loader
+  // before the program gains control. The dynamic loader cannot execute the
+  // constructor functions concurrently since doing that would not guarantee
+  // thread safety of the loaded program. Therefore we can assume sequential
+  // execution of constructor functions here.
+  if (IsHIP) {
+    auto Linkage = CudaGpuBinary ? llvm::GlobalValue::InternalLinkage :
+        llvm::GlobalValue::LinkOnceAnyLinkage;
+    llvm::BasicBlock *IfBlock =
+        llvm::BasicBlock::Create(Context, "if", ModuleCtorFunc);
+    llvm::BasicBlock *ExitBlock =
+        llvm::BasicBlock::Create(Context, "exit", ModuleCtorFunc);
+    // The name, size, and initialization pattern of this variable is part
+    // of HIP ABI.
+    GpuBinaryHandle = new llvm::GlobalVariable(
+        TheModule, VoidPtrPtrTy, /*isConstant=*/false,
+        Linkage,
+        /*Initializer=*/llvm::ConstantPointerNull::get(VoidPtrPtrTy),
+        "__hip_gpubin_handle");
+    GpuBinaryHandle->setAlignment(CGM.getPointerAlign().getAsAlign());
+    // Prevent the weak symbol in different shared libraries being merged.
+    if (Linkage != llvm::GlobalValue::InternalLinkage)
+      GpuBinaryHandle->setVisibility(llvm::GlobalValue::HiddenVisibility);
+    Address GpuBinaryAddr(
+        GpuBinaryHandle,
+        CharUnits::fromQuantity(GpuBinaryHandle->getAlignment()));
+    {
+      auto HandleValue = CtorBuilder.CreateLoad(GpuBinaryAddr);
+      llvm::Constant *Zero =
+          llvm::Constant::getNullValue(HandleValue->getType());
+      llvm::Value *EQZero = CtorBuilder.CreateICmpEQ(HandleValue, Zero);
+      CtorBuilder.CreateCondBr(EQZero, IfBlock, ExitBlock);
+    }
+    {
+      CtorBuilder.SetInsertPoint(IfBlock);
+      // GpuBinaryHandle = __hipRegisterFatBinary(&FatbinWrapper);
+      llvm::CallInst *RegisterFatbinCall = CtorBuilder.CreateCall(
+          RegisterFatbinFunc,
+          CtorBuilder.CreateBitCast(FatbinWrapper, VoidPtrTy));
+      CtorBuilder.CreateStore(RegisterFatbinCall, GpuBinaryAddr);
+      CtorBuilder.CreateBr(ExitBlock);
+    }
+    {
+      CtorBuilder.SetInsertPoint(ExitBlock);
+      // Call __hip_register_globals(GpuBinaryHandle);
+      if (RegisterGlobalsFunc) {
+        auto HandleValue = CtorBuilder.CreateLoad(GpuBinaryAddr);
+        CtorBuilder.CreateCall(RegisterGlobalsFunc, HandleValue);
+      }
+    }
+  } else if (!RelocatableDeviceCode) {
+    // Register binary with CUDA runtime. This is substantially different in
+    // default mode vs. separate compilation!
+    // GpuBinaryHandle = __cudaRegisterFatBinary(&FatbinWrapper);
+    llvm::CallInst *RegisterFatbinCall = CtorBuilder.CreateCall(
+        RegisterFatbinFunc,
+        CtorBuilder.CreateBitCast(FatbinWrapper, VoidPtrTy));
+    GpuBinaryHandle = new llvm::GlobalVariable(
+        TheModule, VoidPtrPtrTy, false, llvm::GlobalValue::InternalLinkage,
+        llvm::ConstantPointerNull::get(VoidPtrPtrTy), "__cuda_gpubin_handle");
+    GpuBinaryHandle->setAlignment(CGM.getPointerAlign().getAsAlign());
+    CtorBuilder.CreateAlignedStore(RegisterFatbinCall, GpuBinaryHandle,
+                                   CGM.getPointerAlign());
+
+    // Call __cuda_register_globals(GpuBinaryHandle);
+    if (RegisterGlobalsFunc)
+      CtorBuilder.CreateCall(RegisterGlobalsFunc, RegisterFatbinCall);
+
+    // Call __cudaRegisterFatBinaryEnd(Handle) if this CUDA version needs it.
+    if (CudaFeatureEnabled(CGM.getTarget().getSDKVersion(),
+                           CudaFeature::CUDA_USES_FATBIN_REGISTER_END)) {
+      // void __cudaRegisterFatBinaryEnd(void **);
+      llvm::FunctionCallee RegisterFatbinEndFunc = CGM.CreateRuntimeFunction(
+          llvm::FunctionType::get(VoidTy, VoidPtrPtrTy, false),
+          "__cudaRegisterFatBinaryEnd");
+      CtorBuilder.CreateCall(RegisterFatbinEndFunc, RegisterFatbinCall);
+    }
+  } else {
+    // Generate a unique module ID.
+    SmallString<64> ModuleID;
+    llvm::raw_svector_ostream OS(ModuleID);
+    OS << ModuleIDPrefix << llvm::format("%" PRIx64, FatbinWrapper->getGUID());
+    llvm::Constant *ModuleIDConstant =
+        makeConstantString(ModuleID.str(), "", ModuleIDSectionName, 32);
+
+    // Create an alias for the FatbinWrapper that nvcc will look for.
+    llvm::GlobalAlias::create(llvm::GlobalValue::ExternalLinkage,
+                              Twine("__fatbinwrap") + ModuleID, FatbinWrapper);
+
+    // void __cudaRegisterLinkedBinary%ModuleID%(void (*)(void *), void *,
+    // void *, void (*)(void **))
+    SmallString<128> RegisterLinkedBinaryName("__cudaRegisterLinkedBinary");
+    RegisterLinkedBinaryName += ModuleID;
+    llvm::FunctionCallee RegisterLinkedBinaryFunc = CGM.CreateRuntimeFunction(
+        getRegisterLinkedBinaryFnTy(), RegisterLinkedBinaryName);
+
+    assert(RegisterGlobalsFunc && "Expecting at least dummy function!");
+    llvm::Value *Args[] = {RegisterGlobalsFunc,
+                           CtorBuilder.CreateBitCast(FatbinWrapper, VoidPtrTy),
+                           ModuleIDConstant,
+                           makeDummyFunction(getCallbackFnTy())};
+    CtorBuilder.CreateCall(RegisterLinkedBinaryFunc, Args);
+  }
+
+  // Create destructor and register it with atexit() the way NVCC does it. Doing
+  // it during regular destructor phase worked in CUDA before 9.2 but results in
+  // double-free in 9.2.
+  if (llvm::Function *CleanupFn = makeModuleDtorFunction()) {
+    // extern "C" int atexit(void (*f)(void));
+    llvm::FunctionType *AtExitTy =
+        llvm::FunctionType::get(IntTy, CleanupFn->getType(), false);
+    llvm::FunctionCallee AtExitFunc =
+        CGM.CreateRuntimeFunction(AtExitTy, "atexit", llvm::AttributeList(),
+                                  /*Local=*/true);
+    CtorBuilder.CreateCall(AtExitFunc, CleanupFn);
+  }
+
+  CtorBuilder.CreateRetVoid();
+  return ModuleCtorFunc;
+}
+
+/// Creates a global destructor function that unregisters the GPU code blob
+/// registered by constructor.
+///
+/// For CUDA:
+/// \code
+/// void __cuda_module_dtor(void*) {
+///     __cudaUnregisterFatBinary(Handle);
+/// }
+/// \endcode
+///
+/// For HIP:
+/// \code
+/// void __hip_module_dtor(void*) {
+///     if (__hip_gpubin_handle) {
+///         __hipUnregisterFatBinary(__hip_gpubin_handle);
+///         __hip_gpubin_handle = 0;
+///     }
+/// }
+/// \endcode
+llvm::Function *CGNVCUDARuntime::makeModuleDtorFunction() {
+  // No need for destructor if we don't have a handle to unregister.
+  if (!GpuBinaryHandle)
+    return nullptr;
+
+  // void __cudaUnregisterFatBinary(void ** handle);
+  llvm::FunctionCallee UnregisterFatbinFunc = CGM.CreateRuntimeFunction(
+      llvm::FunctionType::get(VoidTy, VoidPtrPtrTy, false),
+      addUnderscoredPrefixToName("UnregisterFatBinary"));
+
+  llvm::Function *ModuleDtorFunc = llvm::Function::Create(
+      llvm::FunctionType::get(VoidTy, VoidPtrTy, false),
+      llvm::GlobalValue::InternalLinkage,
+      addUnderscoredPrefixToName("_module_dtor"), &TheModule);
+
+  llvm::BasicBlock *DtorEntryBB =
+      llvm::BasicBlock::Create(Context, "entry", ModuleDtorFunc);
+  CGBuilderTy DtorBuilder(CGM, Context);
+  DtorBuilder.SetInsertPoint(DtorEntryBB);
+
+  Address GpuBinaryAddr(GpuBinaryHandle, CharUnits::fromQuantity(
+                                             GpuBinaryHandle->getAlignment()));
+  auto HandleValue = DtorBuilder.CreateLoad(GpuBinaryAddr);
+  // There is only one HIP fat binary per linked module, however there are
+  // multiple destructor functions. Make sure the fat binary is unregistered
+  // only once.
+  if (CGM.getLangOpts().HIP) {
+    llvm::BasicBlock *IfBlock =
+        llvm::BasicBlock::Create(Context, "if", ModuleDtorFunc);
+    llvm::BasicBlock *ExitBlock =
+        llvm::BasicBlock::Create(Context, "exit", ModuleDtorFunc);
+    llvm::Constant *Zero = llvm::Constant::getNullValue(HandleValue->getType());
+    llvm::Value *NEZero = DtorBuilder.CreateICmpNE(HandleValue, Zero);
+    DtorBuilder.CreateCondBr(NEZero, IfBlock, ExitBlock);
+
+    DtorBuilder.SetInsertPoint(IfBlock);
+    DtorBuilder.CreateCall(UnregisterFatbinFunc, HandleValue);
+    DtorBuilder.CreateStore(Zero, GpuBinaryAddr);
+    DtorBuilder.CreateBr(ExitBlock);
+
+    DtorBuilder.SetInsertPoint(ExitBlock);
+  } else {
+    DtorBuilder.CreateCall(UnregisterFatbinFunc, HandleValue);
+  }
+  DtorBuilder.CreateRetVoid();
+  return ModuleDtorFunc;
+}
+
+std::string CGNVCUDARuntime::getDeviceStubName(llvm::StringRef Name) const {
+  if (!CGM.getLangOpts().HIP)
+    return Name;
+  return (Name + ".stub").str();
+}
+
+CGCUDARuntime *CodeGen::CreateNVCUDARuntime(CodeGenModule &CGM) {
+  return new CGNVCUDARuntime(CGM);
+}