forked from OSchip/llvm-project
318 lines
13 KiB
C++
318 lines
13 KiB
C++
//===----- CGCUDANV.cpp - Interface to NVIDIA CUDA Runtime ----------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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 "llvm/IR/BasicBlock.h"
|
|
#include "llvm/IR/CallSite.h"
|
|
#include "llvm/IR/Constants.h"
|
|
#include "llvm/IR/DerivedTypes.h"
|
|
|
|
using namespace clang;
|
|
using namespace CodeGen;
|
|
|
|
namespace {
|
|
|
|
class CGNVCUDARuntime : public CGCUDARuntime {
|
|
|
|
private:
|
|
llvm::Type *IntTy, *SizeTy, *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
|
|
llvm::SmallVector<llvm::Function *, 16> EmittedKernels;
|
|
/// Keeps track of variables containing handles of GPU binaries. Populated by
|
|
/// ModuleCtorFunction() and used to create corresponding cleanup calls in
|
|
/// ModuleDtorFunction()
|
|
llvm::SmallVector<llvm::GlobalVariable *, 16> GpuBinaryHandles;
|
|
|
|
llvm::Constant *getSetupArgumentFn() const;
|
|
llvm::Constant *getLaunchFn() const;
|
|
|
|
/// Creates a function to register all kernel stubs generated in this module.
|
|
llvm::Function *makeRegisterKernelsFn();
|
|
|
|
/// 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 = "",
|
|
unsigned Alignment = 0) {
|
|
llvm::Constant *Zeros[] = {llvm::ConstantInt::get(SizeTy, 0),
|
|
llvm::ConstantInt::get(SizeTy, 0)};
|
|
auto *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
|
|
return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(),
|
|
ConstStr, Zeros);
|
|
}
|
|
|
|
void emitDeviceStubBody(CodeGenFunction &CGF, FunctionArgList &Args);
|
|
|
|
public:
|
|
CGNVCUDARuntime(CodeGenModule &CGM);
|
|
|
|
void emitDeviceStub(CodeGenFunction &CGF, FunctionArgList &Args) override;
|
|
/// Creates module constructor function
|
|
llvm::Function *makeModuleCtorFunction() override;
|
|
/// Creates module destructor function
|
|
llvm::Function *makeModuleDtorFunction() override;
|
|
};
|
|
|
|
}
|
|
|
|
CGNVCUDARuntime::CGNVCUDARuntime(CodeGenModule &CGM)
|
|
: CGCUDARuntime(CGM), Context(CGM.getLLVMContext()),
|
|
TheModule(CGM.getModule()) {
|
|
CodeGen::CodeGenTypes &Types = CGM.getTypes();
|
|
ASTContext &Ctx = CGM.getContext();
|
|
|
|
IntTy = Types.ConvertType(Ctx.IntTy);
|
|
SizeTy = Types.ConvertType(Ctx.getSizeType());
|
|
VoidTy = llvm::Type::getVoidTy(Context);
|
|
|
|
CharPtrTy = llvm::PointerType::getUnqual(Types.ConvertType(Ctx.CharTy));
|
|
VoidPtrTy = cast<llvm::PointerType>(Types.ConvertType(Ctx.VoidPtrTy));
|
|
VoidPtrPtrTy = VoidPtrTy->getPointerTo();
|
|
}
|
|
|
|
llvm::Constant *CGNVCUDARuntime::getSetupArgumentFn() const {
|
|
// cudaError_t cudaSetupArgument(void *, size_t, size_t)
|
|
std::vector<llvm::Type*> Params;
|
|
Params.push_back(VoidPtrTy);
|
|
Params.push_back(SizeTy);
|
|
Params.push_back(SizeTy);
|
|
return CGM.CreateRuntimeFunction(llvm::FunctionType::get(IntTy,
|
|
Params, false),
|
|
"cudaSetupArgument");
|
|
}
|
|
|
|
llvm::Constant *CGNVCUDARuntime::getLaunchFn() const {
|
|
// cudaError_t cudaLaunch(char *)
|
|
return CGM.CreateRuntimeFunction(
|
|
llvm::FunctionType::get(IntTy, CharPtrTy, false), "cudaLaunch");
|
|
}
|
|
|
|
void CGNVCUDARuntime::emitDeviceStub(CodeGenFunction &CGF,
|
|
FunctionArgList &Args) {
|
|
EmittedKernels.push_back(CGF.CurFn);
|
|
emitDeviceStubBody(CGF, Args);
|
|
}
|
|
|
|
void CGNVCUDARuntime::emitDeviceStubBody(CodeGenFunction &CGF,
|
|
FunctionArgList &Args) {
|
|
// Build the argument value list and the argument stack struct type.
|
|
SmallVector<llvm::Value *, 16> ArgValues;
|
|
std::vector<llvm::Type *> ArgTypes;
|
|
for (FunctionArgList::const_iterator I = Args.begin(), E = Args.end();
|
|
I != E; ++I) {
|
|
llvm::Value *V = CGF.GetAddrOfLocalVar(*I);
|
|
ArgValues.push_back(V);
|
|
assert(isa<llvm::PointerType>(V->getType()) && "Arg type not PointerType");
|
|
ArgTypes.push_back(cast<llvm::PointerType>(V->getType())->getElementType());
|
|
}
|
|
llvm::StructType *ArgStackTy = llvm::StructType::get(Context, ArgTypes);
|
|
|
|
llvm::BasicBlock *EndBlock = CGF.createBasicBlock("setup.end");
|
|
|
|
// Emit the calls to cudaSetupArgument
|
|
llvm::Constant *cudaSetupArgFn = getSetupArgumentFn();
|
|
for (unsigned I = 0, E = Args.size(); I != E; ++I) {
|
|
llvm::Value *Args[3];
|
|
llvm::BasicBlock *NextBlock = CGF.createBasicBlock("setup.next");
|
|
Args[0] = CGF.Builder.CreatePointerCast(ArgValues[I], VoidPtrTy);
|
|
Args[1] = CGF.Builder.CreateIntCast(
|
|
llvm::ConstantExpr::getSizeOf(ArgTypes[I]),
|
|
SizeTy, false);
|
|
Args[2] = CGF.Builder.CreateIntCast(
|
|
llvm::ConstantExpr::getOffsetOf(ArgStackTy, I),
|
|
SizeTy, false);
|
|
llvm::CallSite CS = CGF.EmitRuntimeCallOrInvoke(cudaSetupArgFn, Args);
|
|
llvm::Constant *Zero = llvm::ConstantInt::get(IntTy, 0);
|
|
llvm::Value *CSZero = CGF.Builder.CreateICmpEQ(CS.getInstruction(), Zero);
|
|
CGF.Builder.CreateCondBr(CSZero, NextBlock, EndBlock);
|
|
CGF.EmitBlock(NextBlock);
|
|
}
|
|
|
|
// Emit the call to cudaLaunch
|
|
llvm::Constant *cudaLaunchFn = getLaunchFn();
|
|
llvm::Value *Arg = CGF.Builder.CreatePointerCast(CGF.CurFn, CharPtrTy);
|
|
CGF.EmitRuntimeCallOrInvoke(cudaLaunchFn, Arg);
|
|
CGF.EmitBranch(EndBlock);
|
|
|
|
CGF.EmitBlock(EndBlock);
|
|
}
|
|
|
|
/// Creates internal function to register all kernel stubs generated in this
|
|
/// module with the CUDA runtime.
|
|
/// \code
|
|
/// void __cuda_register_kernels(void** GpuBinaryHandle) {
|
|
/// __cudaRegisterFunction(GpuBinaryHandle,Kernel0,...);
|
|
/// ...
|
|
/// __cudaRegisterFunction(GpuBinaryHandle,KernelM,...);
|
|
/// }
|
|
/// \endcode
|
|
llvm::Function *CGNVCUDARuntime::makeRegisterKernelsFn() {
|
|
llvm::Function *RegisterKernelsFunc = llvm::Function::Create(
|
|
llvm::FunctionType::get(VoidTy, VoidPtrPtrTy, false),
|
|
llvm::GlobalValue::InternalLinkage, "__cuda_register_kernels", &TheModule);
|
|
llvm::BasicBlock *EntryBB =
|
|
llvm::BasicBlock::Create(Context, "entry", RegisterKernelsFunc);
|
|
CGBuilderTy Builder(Context);
|
|
Builder.SetInsertPoint(EntryBB);
|
|
|
|
// void __cudaRegisterFunction(void **, const char *, char *, const char *,
|
|
// int, uint3*, uint3*, dim3*, dim3*, int*)
|
|
std::vector<llvm::Type *> RegisterFuncParams = {
|
|
VoidPtrPtrTy, CharPtrTy, CharPtrTy, CharPtrTy, IntTy,
|
|
VoidPtrTy, VoidPtrTy, VoidPtrTy, VoidPtrTy, IntTy->getPointerTo()};
|
|
llvm::Constant *RegisterFunc = CGM.CreateRuntimeFunction(
|
|
llvm::FunctionType::get(IntTy, RegisterFuncParams, false),
|
|
"__cudaRegisterFunction");
|
|
|
|
// Extract GpuBinaryHandle passed as the first argument passed to
|
|
// __cuda_register_kernels() and generate __cudaRegisterFunction() call for
|
|
// each emitted kernel.
|
|
llvm::Argument &GpuBinaryHandlePtr = *RegisterKernelsFunc->arg_begin();
|
|
for (llvm::Function *Kernel : EmittedKernels) {
|
|
llvm::Constant *KernelName = makeConstantString(Kernel->getName());
|
|
llvm::Constant *NullPtr = llvm::ConstantPointerNull::get(VoidPtrTy);
|
|
llvm::Value *args[] = {
|
|
&GpuBinaryHandlePtr, Builder.CreateBitCast(Kernel, VoidPtrTy),
|
|
KernelName, KernelName, llvm::ConstantInt::get(IntTy, -1), NullPtr,
|
|
NullPtr, NullPtr, NullPtr,
|
|
llvm::ConstantPointerNull::get(IntTy->getPointerTo())};
|
|
Builder.CreateCall(RegisterFunc, args);
|
|
}
|
|
|
|
Builder.CreateRetVoid();
|
|
return RegisterKernelsFunc;
|
|
}
|
|
|
|
/// Creates a global constructor function for the module:
|
|
/// \code
|
|
/// void __cuda_module_ctor(void*) {
|
|
/// Handle0 = __cudaRegisterFatBinary(GpuBinaryBlob0);
|
|
/// __cuda_register_kernels(Handle0);
|
|
/// ...
|
|
/// HandleN = __cudaRegisterFatBinary(GpuBinaryBlobN);
|
|
/// __cuda_register_kernels(HandleN);
|
|
/// }
|
|
/// \endcode
|
|
llvm::Function *CGNVCUDARuntime::makeModuleCtorFunction() {
|
|
// void __cuda_register_kernels(void* handle);
|
|
llvm::Function *RegisterKernelsFunc = makeRegisterKernelsFn();
|
|
// void ** __cudaRegisterFatBinary(void *);
|
|
llvm::Constant *RegisterFatbinFunc = CGM.CreateRuntimeFunction(
|
|
llvm::FunctionType::get(VoidPtrPtrTy, VoidPtrTy, false),
|
|
"__cudaRegisterFatBinary");
|
|
// struct { int magic, int version, void * gpu_binary, void * dont_care };
|
|
llvm::StructType *FatbinWrapperTy =
|
|
llvm::StructType::get(IntTy, IntTy, VoidPtrTy, VoidPtrTy, nullptr);
|
|
|
|
llvm::Function *ModuleCtorFunc = llvm::Function::Create(
|
|
llvm::FunctionType::get(VoidTy, VoidPtrTy, false),
|
|
llvm::GlobalValue::InternalLinkage, "__cuda_module_ctor", &TheModule);
|
|
llvm::BasicBlock *CtorEntryBB =
|
|
llvm::BasicBlock::Create(Context, "entry", ModuleCtorFunc);
|
|
CGBuilderTy CtorBuilder(Context);
|
|
|
|
CtorBuilder.SetInsertPoint(CtorEntryBB);
|
|
|
|
// For each GPU binary, register it with the CUDA runtime and store returned
|
|
// handle in a global variable and save the handle in GpuBinaryHandles vector
|
|
// 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.
|
|
for (const std::string &GpuBinaryFileName :
|
|
CGM.getCodeGenOpts().CudaGpuBinaryFileNames) {
|
|
llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> GpuBinaryOrErr =
|
|
llvm::MemoryBuffer::getFileOrSTDIN(GpuBinaryFileName);
|
|
if (std::error_code EC = GpuBinaryOrErr.getError()) {
|
|
CGM.getDiags().Report(diag::err_cannot_open_file) << GpuBinaryFileName
|
|
<< EC.message();
|
|
continue;
|
|
}
|
|
|
|
// Create initialized wrapper structure that points to the loaded GPU binary
|
|
llvm::Constant *Values[] = {
|
|
llvm::ConstantInt::get(IntTy, 0x466243b1), // Fatbin wrapper magic.
|
|
llvm::ConstantInt::get(IntTy, 1), // Fatbin version.
|
|
makeConstantString(GpuBinaryOrErr.get()->getBuffer(), "", 16), // Data.
|
|
llvm::ConstantPointerNull::get(VoidPtrTy)}; // Unused in fatbin v1.
|
|
llvm::GlobalVariable *FatbinWrapper = new llvm::GlobalVariable(
|
|
TheModule, FatbinWrapperTy, true, llvm::GlobalValue::InternalLinkage,
|
|
llvm::ConstantStruct::get(FatbinWrapperTy, Values),
|
|
"__cuda_fatbin_wrapper");
|
|
|
|
// GpuBinaryHandle = __cudaRegisterFatBinary(&FatbinWrapper);
|
|
llvm::CallInst *RegisterFatbinCall = CtorBuilder.CreateCall(
|
|
RegisterFatbinFunc,
|
|
CtorBuilder.CreateBitCast(FatbinWrapper, VoidPtrTy));
|
|
llvm::GlobalVariable *GpuBinaryHandle = new llvm::GlobalVariable(
|
|
TheModule, VoidPtrPtrTy, false, llvm::GlobalValue::InternalLinkage,
|
|
llvm::ConstantPointerNull::get(VoidPtrPtrTy), "__cuda_gpubin_handle");
|
|
CtorBuilder.CreateStore(RegisterFatbinCall, GpuBinaryHandle, false);
|
|
|
|
// Call __cuda_register_kernels(GpuBinaryHandle);
|
|
CtorBuilder.CreateCall(RegisterKernelsFunc, RegisterFatbinCall);
|
|
|
|
// Save GpuBinaryHandle so we can unregister it in destructor.
|
|
GpuBinaryHandles.push_back(GpuBinaryHandle);
|
|
}
|
|
|
|
CtorBuilder.CreateRetVoid();
|
|
return ModuleCtorFunc;
|
|
}
|
|
|
|
/// Creates a global destructor function that unregisters all GPU code blobs
|
|
/// registered by constructor.
|
|
/// \code
|
|
/// void __cuda_module_dtor(void*) {
|
|
/// __cudaUnregisterFatBinary(Handle0);
|
|
/// ...
|
|
/// __cudaUnregisterFatBinary(HandleN);
|
|
/// }
|
|
/// \endcode
|
|
llvm::Function *CGNVCUDARuntime::makeModuleDtorFunction() {
|
|
// void __cudaUnregisterFatBinary(void ** handle);
|
|
llvm::Constant *UnregisterFatbinFunc = CGM.CreateRuntimeFunction(
|
|
llvm::FunctionType::get(VoidTy, VoidPtrPtrTy, false),
|
|
"__cudaUnregisterFatBinary");
|
|
|
|
llvm::Function *ModuleDtorFunc = llvm::Function::Create(
|
|
llvm::FunctionType::get(VoidTy, VoidPtrTy, false),
|
|
llvm::GlobalValue::InternalLinkage, "__cuda_module_dtor", &TheModule);
|
|
llvm::BasicBlock *DtorEntryBB =
|
|
llvm::BasicBlock::Create(Context, "entry", ModuleDtorFunc);
|
|
CGBuilderTy DtorBuilder(Context);
|
|
DtorBuilder.SetInsertPoint(DtorEntryBB);
|
|
|
|
for (llvm::GlobalVariable *GpuBinaryHandle : GpuBinaryHandles) {
|
|
DtorBuilder.CreateCall(UnregisterFatbinFunc,
|
|
DtorBuilder.CreateLoad(GpuBinaryHandle, false));
|
|
}
|
|
|
|
DtorBuilder.CreateRetVoid();
|
|
return ModuleDtorFunc;
|
|
}
|
|
|
|
CGCUDARuntime *CodeGen::CreateNVCUDARuntime(CodeGenModule &CGM) {
|
|
return new CGNVCUDARuntime(CGM);
|
|
}
|