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Diffstat (limited to 'clang/lib/Driver/ToolChains/Cuda.cpp')
| -rw-r--r-- | clang/lib/Driver/ToolChains/Cuda.cpp | 885 |
1 files changed, 885 insertions, 0 deletions
diff --git a/clang/lib/Driver/ToolChains/Cuda.cpp b/clang/lib/Driver/ToolChains/Cuda.cpp new file mode 100644 index 000000000000..8c704a3078ad --- /dev/null +++ b/clang/lib/Driver/ToolChains/Cuda.cpp @@ -0,0 +1,885 @@ +//===--- Cuda.cpp - Cuda Tool and ToolChain Implementations -----*- C++ -*-===// +// +// 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 +// +//===----------------------------------------------------------------------===// + +#include "Cuda.h" +#include "CommonArgs.h" +#include "InputInfo.h" +#include "clang/Basic/Cuda.h" +#include "clang/Config/config.h" +#include "clang/Driver/Compilation.h" +#include "clang/Driver/Distro.h" +#include "clang/Driver/Driver.h" +#include "clang/Driver/DriverDiagnostic.h" +#include "clang/Driver/Options.h" +#include "llvm/Option/ArgList.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/Process.h" +#include "llvm/Support/Program.h" +#include "llvm/Support/VirtualFileSystem.h" +#include <system_error> + +using namespace clang::driver; +using namespace clang::driver::toolchains; +using namespace clang::driver::tools; +using namespace clang; +using namespace llvm::opt; + +// Parses the contents of version.txt in an CUDA installation. It should +// contain one line of the from e.g. "CUDA Version 7.5.2". +static CudaVersion ParseCudaVersionFile(llvm::StringRef V) { + if (!V.startswith("CUDA Version ")) + return CudaVersion::UNKNOWN; + V = V.substr(strlen("CUDA Version ")); + int Major = -1, Minor = -1; + auto First = V.split('.'); + auto Second = First.second.split('.'); + if (First.first.getAsInteger(10, Major) || + Second.first.getAsInteger(10, Minor)) + return CudaVersion::UNKNOWN; + + if (Major == 7 && Minor == 0) { + // This doesn't appear to ever happen -- version.txt doesn't exist in the + // CUDA 7 installs I've seen. But no harm in checking. + return CudaVersion::CUDA_70; + } + if (Major == 7 && Minor == 5) + return CudaVersion::CUDA_75; + if (Major == 8 && Minor == 0) + return CudaVersion::CUDA_80; + if (Major == 9 && Minor == 0) + return CudaVersion::CUDA_90; + if (Major == 9 && Minor == 1) + return CudaVersion::CUDA_91; + if (Major == 9 && Minor == 2) + return CudaVersion::CUDA_92; + if (Major == 10 && Minor == 0) + return CudaVersion::CUDA_100; + if (Major == 10 && Minor == 1) + return CudaVersion::CUDA_101; + return CudaVersion::UNKNOWN; +} + +CudaInstallationDetector::CudaInstallationDetector( + const Driver &D, const llvm::Triple &HostTriple, + const llvm::opt::ArgList &Args) + : D(D) { + struct Candidate { + std::string Path; + bool StrictChecking; + + Candidate(std::string Path, bool StrictChecking = false) + : Path(Path), StrictChecking(StrictChecking) {} + }; + SmallVector<Candidate, 4> Candidates; + + // In decreasing order so we prefer newer versions to older versions. + std::initializer_list<const char *> Versions = {"8.0", "7.5", "7.0"}; + + if (Args.hasArg(clang::driver::options::OPT_cuda_path_EQ)) { + Candidates.emplace_back( + Args.getLastArgValue(clang::driver::options::OPT_cuda_path_EQ).str()); + } else if (HostTriple.isOSWindows()) { + for (const char *Ver : Versions) + Candidates.emplace_back( + D.SysRoot + "/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v" + + Ver); + } else { + if (!Args.hasArg(clang::driver::options::OPT_cuda_path_ignore_env)) { + // Try to find ptxas binary. If the executable is located in a directory + // called 'bin/', its parent directory might be a good guess for a valid + // CUDA installation. + // However, some distributions might installs 'ptxas' to /usr/bin. In that + // case the candidate would be '/usr' which passes the following checks + // because '/usr/include' exists as well. To avoid this case, we always + // check for the directory potentially containing files for libdevice, + // even if the user passes -nocudalib. + if (llvm::ErrorOr<std::string> ptxas = + llvm::sys::findProgramByName("ptxas")) { + SmallString<256> ptxasAbsolutePath; + llvm::sys::fs::real_path(*ptxas, ptxasAbsolutePath); + + StringRef ptxasDir = llvm::sys::path::parent_path(ptxasAbsolutePath); + if (llvm::sys::path::filename(ptxasDir) == "bin") + Candidates.emplace_back(llvm::sys::path::parent_path(ptxasDir), + /*StrictChecking=*/true); + } + } + + Candidates.emplace_back(D.SysRoot + "/usr/local/cuda"); + for (const char *Ver : Versions) + Candidates.emplace_back(D.SysRoot + "/usr/local/cuda-" + Ver); + + if (Distro(D.getVFS()).IsDebian() || Distro(D.getVFS()).IsUbuntu()) + // Special case for Debian to have nvidia-cuda-toolkit work + // out of the box. More info on http://bugs.debian.org/882505 + Candidates.emplace_back(D.SysRoot + "/usr/lib/cuda"); + } + + bool NoCudaLib = Args.hasArg(options::OPT_nogpulib); + + for (const auto &Candidate : Candidates) { + InstallPath = Candidate.Path; + if (InstallPath.empty() || !D.getVFS().exists(InstallPath)) + continue; + + BinPath = InstallPath + "/bin"; + IncludePath = InstallPath + "/include"; + LibDevicePath = InstallPath + "/nvvm/libdevice"; + + auto &FS = D.getVFS(); + if (!(FS.exists(IncludePath) && FS.exists(BinPath))) + continue; + bool CheckLibDevice = (!NoCudaLib || Candidate.StrictChecking); + if (CheckLibDevice && !FS.exists(LibDevicePath)) + continue; + + // On Linux, we have both lib and lib64 directories, and we need to choose + // based on our triple. On MacOS, we have only a lib directory. + // + // It's sufficient for our purposes to be flexible: If both lib and lib64 + // exist, we choose whichever one matches our triple. Otherwise, if only + // lib exists, we use it. + if (HostTriple.isArch64Bit() && FS.exists(InstallPath + "/lib64")) + LibPath = InstallPath + "/lib64"; + else if (FS.exists(InstallPath + "/lib")) + LibPath = InstallPath + "/lib"; + else + continue; + + llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> VersionFile = + FS.getBufferForFile(InstallPath + "/version.txt"); + if (!VersionFile) { + // CUDA 7.0 doesn't have a version.txt, so guess that's our version if + // version.txt isn't present. + Version = CudaVersion::CUDA_70; + } else { + Version = ParseCudaVersionFile((*VersionFile)->getBuffer()); + } + + if (Version >= CudaVersion::CUDA_90) { + // CUDA-9+ uses single libdevice file for all GPU variants. + std::string FilePath = LibDevicePath + "/libdevice.10.bc"; + if (FS.exists(FilePath)) { + for (const char *GpuArchName : + {"sm_30", "sm_32", "sm_35", "sm_37", "sm_50", "sm_52", "sm_53", + "sm_60", "sm_61", "sm_62", "sm_70", "sm_72", "sm_75"}) { + const CudaArch GpuArch = StringToCudaArch(GpuArchName); + if (Version >= MinVersionForCudaArch(GpuArch) && + Version <= MaxVersionForCudaArch(GpuArch)) + LibDeviceMap[GpuArchName] = FilePath; + } + } + } else { + std::error_code EC; + for (llvm::sys::fs::directory_iterator LI(LibDevicePath, EC), LE; + !EC && LI != LE; LI = LI.increment(EC)) { + StringRef FilePath = LI->path(); + StringRef FileName = llvm::sys::path::filename(FilePath); + // Process all bitcode filenames that look like + // libdevice.compute_XX.YY.bc + const StringRef LibDeviceName = "libdevice."; + if (!(FileName.startswith(LibDeviceName) && FileName.endswith(".bc"))) + continue; + StringRef GpuArch = FileName.slice( + LibDeviceName.size(), FileName.find('.', LibDeviceName.size())); + LibDeviceMap[GpuArch] = FilePath.str(); + // Insert map entries for specific devices with this compute + // capability. NVCC's choice of the libdevice library version is + // rather peculiar and depends on the CUDA version. + if (GpuArch == "compute_20") { + LibDeviceMap["sm_20"] = FilePath; + LibDeviceMap["sm_21"] = FilePath; + LibDeviceMap["sm_32"] = FilePath; + } else if (GpuArch == "compute_30") { + LibDeviceMap["sm_30"] = FilePath; + if (Version < CudaVersion::CUDA_80) { + LibDeviceMap["sm_50"] = FilePath; + LibDeviceMap["sm_52"] = FilePath; + LibDeviceMap["sm_53"] = FilePath; + } + LibDeviceMap["sm_60"] = FilePath; + LibDeviceMap["sm_61"] = FilePath; + LibDeviceMap["sm_62"] = FilePath; + } else if (GpuArch == "compute_35") { + LibDeviceMap["sm_35"] = FilePath; + LibDeviceMap["sm_37"] = FilePath; + } else if (GpuArch == "compute_50") { + if (Version >= CudaVersion::CUDA_80) { + LibDeviceMap["sm_50"] = FilePath; + LibDeviceMap["sm_52"] = FilePath; + LibDeviceMap["sm_53"] = FilePath; + } + } + } + } + + // Check that we have found at least one libdevice that we can link in if + // -nocudalib hasn't been specified. + if (LibDeviceMap.empty() && !NoCudaLib) + continue; + + IsValid = true; + break; + } +} + +void CudaInstallationDetector::AddCudaIncludeArgs( + const ArgList &DriverArgs, ArgStringList &CC1Args) const { + if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) { + // Add cuda_wrappers/* to our system include path. This lets us wrap + // standard library headers. + SmallString<128> P(D.ResourceDir); + llvm::sys::path::append(P, "include"); + llvm::sys::path::append(P, "cuda_wrappers"); + CC1Args.push_back("-internal-isystem"); + CC1Args.push_back(DriverArgs.MakeArgString(P)); + } + + if (DriverArgs.hasArg(options::OPT_nocudainc)) + return; + + if (!isValid()) { + D.Diag(diag::err_drv_no_cuda_installation); + return; + } + + CC1Args.push_back("-internal-isystem"); + CC1Args.push_back(DriverArgs.MakeArgString(getIncludePath())); + CC1Args.push_back("-include"); + CC1Args.push_back("__clang_cuda_runtime_wrapper.h"); +} + +void CudaInstallationDetector::CheckCudaVersionSupportsArch( + CudaArch Arch) const { + if (Arch == CudaArch::UNKNOWN || Version == CudaVersion::UNKNOWN || + ArchsWithBadVersion.count(Arch) > 0) + return; + + auto MinVersion = MinVersionForCudaArch(Arch); + auto MaxVersion = MaxVersionForCudaArch(Arch); + if (Version < MinVersion || Version > MaxVersion) { + ArchsWithBadVersion.insert(Arch); + D.Diag(diag::err_drv_cuda_version_unsupported) + << CudaArchToString(Arch) << CudaVersionToString(MinVersion) + << CudaVersionToString(MaxVersion) << InstallPath + << CudaVersionToString(Version); + } +} + +void CudaInstallationDetector::print(raw_ostream &OS) const { + if (isValid()) + OS << "Found CUDA installation: " << InstallPath << ", version " + << CudaVersionToString(Version) << "\n"; +} + +namespace { +/// Debug info level for the NVPTX devices. We may need to emit different debug +/// info level for the host and for the device itselfi. This type controls +/// emission of the debug info for the devices. It either prohibits disable info +/// emission completely, or emits debug directives only, or emits same debug +/// info as for the host. +enum DeviceDebugInfoLevel { + DisableDebugInfo, /// Do not emit debug info for the devices. + DebugDirectivesOnly, /// Emit only debug directives. + EmitSameDebugInfoAsHost, /// Use the same debug info level just like for the + /// host. +}; +} // anonymous namespace + +/// Define debug info level for the NVPTX devices. If the debug info for both +/// the host and device are disabled (-g0/-ggdb0 or no debug options at all). If +/// only debug directives are requested for the both host and device +/// (-gline-directvies-only), or the debug info only for the device is disabled +/// (optimization is on and --cuda-noopt-device-debug was not specified), the +/// debug directves only must be emitted for the device. Otherwise, use the same +/// debug info level just like for the host (with the limitations of only +/// supported DWARF2 standard). +static DeviceDebugInfoLevel mustEmitDebugInfo(const ArgList &Args) { + const Arg *A = Args.getLastArg(options::OPT_O_Group); + bool IsDebugEnabled = !A || A->getOption().matches(options::OPT_O0) || + Args.hasFlag(options::OPT_cuda_noopt_device_debug, + options::OPT_no_cuda_noopt_device_debug, + /*Default=*/false); + if (const Arg *A = Args.getLastArg(options::OPT_g_Group)) { + const Option &Opt = A->getOption(); + if (Opt.matches(options::OPT_gN_Group)) { + if (Opt.matches(options::OPT_g0) || Opt.matches(options::OPT_ggdb0)) + return DisableDebugInfo; + if (Opt.matches(options::OPT_gline_directives_only)) + return DebugDirectivesOnly; + } + return IsDebugEnabled ? EmitSameDebugInfoAsHost : DebugDirectivesOnly; + } + return DisableDebugInfo; +} + +void NVPTX::Assembler::ConstructJob(Compilation &C, const JobAction &JA, + const InputInfo &Output, + const InputInfoList &Inputs, + const ArgList &Args, + const char *LinkingOutput) const { + const auto &TC = + static_cast<const toolchains::CudaToolChain &>(getToolChain()); + assert(TC.getTriple().isNVPTX() && "Wrong platform"); + + StringRef GPUArchName; + // If this is an OpenMP action we need to extract the device architecture + // from the -march=arch option. This option may come from -Xopenmp-target + // flag or the default value. + if (JA.isDeviceOffloading(Action::OFK_OpenMP)) { + GPUArchName = Args.getLastArgValue(options::OPT_march_EQ); + assert(!GPUArchName.empty() && "Must have an architecture passed in."); + } else + GPUArchName = JA.getOffloadingArch(); + + // Obtain architecture from the action. + CudaArch gpu_arch = StringToCudaArch(GPUArchName); + assert(gpu_arch != CudaArch::UNKNOWN && + "Device action expected to have an architecture."); + + // Check that our installation's ptxas supports gpu_arch. + if (!Args.hasArg(options::OPT_no_cuda_version_check)) { + TC.CudaInstallation.CheckCudaVersionSupportsArch(gpu_arch); + } + + ArgStringList CmdArgs; + CmdArgs.push_back(TC.getTriple().isArch64Bit() ? "-m64" : "-m32"); + DeviceDebugInfoLevel DIKind = mustEmitDebugInfo(Args); + if (DIKind == EmitSameDebugInfoAsHost) { + // ptxas does not accept -g option if optimization is enabled, so + // we ignore the compiler's -O* options if we want debug info. + CmdArgs.push_back("-g"); + CmdArgs.push_back("--dont-merge-basicblocks"); + CmdArgs.push_back("--return-at-end"); + } else if (Arg *A = Args.getLastArg(options::OPT_O_Group)) { + // Map the -O we received to -O{0,1,2,3}. + // + // TODO: Perhaps we should map host -O2 to ptxas -O3. -O3 is ptxas's + // default, so it may correspond more closely to the spirit of clang -O2. + + // -O3 seems like the least-bad option when -Osomething is specified to + // clang but it isn't handled below. + StringRef OOpt = "3"; + if (A->getOption().matches(options::OPT_O4) || + A->getOption().matches(options::OPT_Ofast)) + OOpt = "3"; + else if (A->getOption().matches(options::OPT_O0)) + OOpt = "0"; + else if (A->getOption().matches(options::OPT_O)) { + // -Os, -Oz, and -O(anything else) map to -O2, for lack of better options. + OOpt = llvm::StringSwitch<const char *>(A->getValue()) + .Case("1", "1") + .Case("2", "2") + .Case("3", "3") + .Case("s", "2") + .Case("z", "2") + .Default("2"); + } + CmdArgs.push_back(Args.MakeArgString(llvm::Twine("-O") + OOpt)); + } else { + // If no -O was passed, pass -O0 to ptxas -- no opt flag should correspond + // to no optimizations, but ptxas's default is -O3. + CmdArgs.push_back("-O0"); + } + if (DIKind == DebugDirectivesOnly) + CmdArgs.push_back("-lineinfo"); + + // Pass -v to ptxas if it was passed to the driver. + if (Args.hasArg(options::OPT_v)) + CmdArgs.push_back("-v"); + + CmdArgs.push_back("--gpu-name"); + CmdArgs.push_back(Args.MakeArgString(CudaArchToString(gpu_arch))); + CmdArgs.push_back("--output-file"); + CmdArgs.push_back(Args.MakeArgString(TC.getInputFilename(Output))); + for (const auto& II : Inputs) + CmdArgs.push_back(Args.MakeArgString(II.getFilename())); + + for (const auto& A : Args.getAllArgValues(options::OPT_Xcuda_ptxas)) + CmdArgs.push_back(Args.MakeArgString(A)); + + bool Relocatable = false; + if (JA.isOffloading(Action::OFK_OpenMP)) + // In OpenMP we need to generate relocatable code. + Relocatable = Args.hasFlag(options::OPT_fopenmp_relocatable_target, + options::OPT_fnoopenmp_relocatable_target, + /*Default=*/true); + else if (JA.isOffloading(Action::OFK_Cuda)) + Relocatable = Args.hasFlag(options::OPT_fgpu_rdc, + options::OPT_fno_gpu_rdc, /*Default=*/false); + + if (Relocatable) + CmdArgs.push_back("-c"); + + const char *Exec; + if (Arg *A = Args.getLastArg(options::OPT_ptxas_path_EQ)) + Exec = A->getValue(); + else + Exec = Args.MakeArgString(TC.GetProgramPath("ptxas")); + C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs)); +} + +static bool shouldIncludePTX(const ArgList &Args, const char *gpu_arch) { + bool includePTX = true; + for (Arg *A : Args) { + if (!(A->getOption().matches(options::OPT_cuda_include_ptx_EQ) || + A->getOption().matches(options::OPT_no_cuda_include_ptx_EQ))) + continue; + A->claim(); + const StringRef ArchStr = A->getValue(); + if (ArchStr == "all" || ArchStr == gpu_arch) { + includePTX = A->getOption().matches(options::OPT_cuda_include_ptx_EQ); + continue; + } + } + return includePTX; +} + +// All inputs to this linker must be from CudaDeviceActions, as we need to look +// at the Inputs' Actions in order to figure out which GPU architecture they +// correspond to. +void NVPTX::Linker::ConstructJob(Compilation &C, const JobAction &JA, + const InputInfo &Output, + const InputInfoList &Inputs, + const ArgList &Args, + const char *LinkingOutput) const { + const auto &TC = + static_cast<const toolchains::CudaToolChain &>(getToolChain()); + assert(TC.getTriple().isNVPTX() && "Wrong platform"); + + ArgStringList CmdArgs; + if (TC.CudaInstallation.version() <= CudaVersion::CUDA_100) + CmdArgs.push_back("--cuda"); + CmdArgs.push_back(TC.getTriple().isArch64Bit() ? "-64" : "-32"); + CmdArgs.push_back(Args.MakeArgString("--create")); + CmdArgs.push_back(Args.MakeArgString(Output.getFilename())); + if (mustEmitDebugInfo(Args) == EmitSameDebugInfoAsHost) + CmdArgs.push_back("-g"); + + for (const auto& II : Inputs) { + auto *A = II.getAction(); + assert(A->getInputs().size() == 1 && + "Device offload action is expected to have a single input"); + const char *gpu_arch_str = A->getOffloadingArch(); + assert(gpu_arch_str && + "Device action expected to have associated a GPU architecture!"); + CudaArch gpu_arch = StringToCudaArch(gpu_arch_str); + + if (II.getType() == types::TY_PP_Asm && + !shouldIncludePTX(Args, gpu_arch_str)) + continue; + // We need to pass an Arch of the form "sm_XX" for cubin files and + // "compute_XX" for ptx. + const char *Arch = + (II.getType() == types::TY_PP_Asm) + ? CudaVirtualArchToString(VirtualArchForCudaArch(gpu_arch)) + : gpu_arch_str; + CmdArgs.push_back(Args.MakeArgString(llvm::Twine("--image=profile=") + + Arch + ",file=" + II.getFilename())); + } + + for (const auto& A : Args.getAllArgValues(options::OPT_Xcuda_fatbinary)) + CmdArgs.push_back(Args.MakeArgString(A)); + + const char *Exec = Args.MakeArgString(TC.GetProgramPath("fatbinary")); + C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs)); +} + +void NVPTX::OpenMPLinker::ConstructJob(Compilation &C, const JobAction &JA, + const InputInfo &Output, + const InputInfoList &Inputs, + const ArgList &Args, + const char *LinkingOutput) const { + const auto &TC = + static_cast<const toolchains::CudaToolChain &>(getToolChain()); + assert(TC.getTriple().isNVPTX() && "Wrong platform"); + + ArgStringList CmdArgs; + + // OpenMP uses nvlink to link cubin files. The result will be embedded in the + // host binary by the host linker. + assert(!JA.isHostOffloading(Action::OFK_OpenMP) && + "CUDA toolchain not expected for an OpenMP host device."); + + if (Output.isFilename()) { + CmdArgs.push_back("-o"); + CmdArgs.push_back(Output.getFilename()); + } else + assert(Output.isNothing() && "Invalid output."); + if (mustEmitDebugInfo(Args) == EmitSameDebugInfoAsHost) + CmdArgs.push_back("-g"); + + if (Args.hasArg(options::OPT_v)) + CmdArgs.push_back("-v"); + + StringRef GPUArch = + Args.getLastArgValue(options::OPT_march_EQ); + assert(!GPUArch.empty() && "At least one GPU Arch required for ptxas."); + + CmdArgs.push_back("-arch"); + CmdArgs.push_back(Args.MakeArgString(GPUArch)); + + // Assume that the directory specified with --libomptarget_nvptx_path + // contains the static library libomptarget-nvptx.a. + if (const Arg *A = Args.getLastArg(options::OPT_libomptarget_nvptx_path_EQ)) + CmdArgs.push_back(Args.MakeArgString(Twine("-L") + A->getValue())); + + // Add paths specified in LIBRARY_PATH environment variable as -L options. + addDirectoryList(Args, CmdArgs, "-L", "LIBRARY_PATH"); + + // Add paths for the default clang library path. + SmallString<256> DefaultLibPath = + llvm::sys::path::parent_path(TC.getDriver().Dir); + llvm::sys::path::append(DefaultLibPath, "lib" CLANG_LIBDIR_SUFFIX); + CmdArgs.push_back(Args.MakeArgString(Twine("-L") + DefaultLibPath)); + + // Add linking against library implementing OpenMP calls on NVPTX target. + CmdArgs.push_back("-lomptarget-nvptx"); + + for (const auto &II : Inputs) { + if (II.getType() == types::TY_LLVM_IR || + II.getType() == types::TY_LTO_IR || + II.getType() == types::TY_LTO_BC || + II.getType() == types::TY_LLVM_BC) { + C.getDriver().Diag(diag::err_drv_no_linker_llvm_support) + << getToolChain().getTripleString(); + continue; + } + + // Currently, we only pass the input files to the linker, we do not pass + // any libraries that may be valid only for the host. + if (!II.isFilename()) + continue; + + const char *CubinF = C.addTempFile( + C.getArgs().MakeArgString(getToolChain().getInputFilename(II))); + + CmdArgs.push_back(CubinF); + } + + const char *Exec = + Args.MakeArgString(getToolChain().GetProgramPath("nvlink")); + C.addCommand(std::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs)); +} + +/// CUDA toolchain. Our assembler is ptxas, and our "linker" is fatbinary, +/// which isn't properly a linker but nonetheless performs the step of stitching +/// together object files from the assembler into a single blob. + +CudaToolChain::CudaToolChain(const Driver &D, const llvm::Triple &Triple, + const ToolChain &HostTC, const ArgList &Args, + const Action::OffloadKind OK) + : ToolChain(D, Triple, Args), HostTC(HostTC), + CudaInstallation(D, HostTC.getTriple(), Args), OK(OK) { + if (CudaInstallation.isValid()) + getProgramPaths().push_back(CudaInstallation.getBinPath()); + // Lookup binaries into the driver directory, this is used to + // discover the clang-offload-bundler executable. + getProgramPaths().push_back(getDriver().Dir); +} + +std::string CudaToolChain::getInputFilename(const InputInfo &Input) const { + // Only object files are changed, for example assembly files keep their .s + // extensions. CUDA also continues to use .o as they don't use nvlink but + // fatbinary. + if (!(OK == Action::OFK_OpenMP && Input.getType() == types::TY_Object)) + return ToolChain::getInputFilename(Input); + + // Replace extension for object files with cubin because nvlink relies on + // these particular file names. + SmallString<256> Filename(ToolChain::getInputFilename(Input)); + llvm::sys::path::replace_extension(Filename, "cubin"); + return Filename.str(); +} + +void CudaToolChain::addClangTargetOptions( + const llvm::opt::ArgList &DriverArgs, + llvm::opt::ArgStringList &CC1Args, + Action::OffloadKind DeviceOffloadingKind) const { + HostTC.addClangTargetOptions(DriverArgs, CC1Args, DeviceOffloadingKind); + + StringRef GpuArch = DriverArgs.getLastArgValue(options::OPT_march_EQ); + assert(!GpuArch.empty() && "Must have an explicit GPU arch."); + assert((DeviceOffloadingKind == Action::OFK_OpenMP || + DeviceOffloadingKind == Action::OFK_Cuda) && + "Only OpenMP or CUDA offloading kinds are supported for NVIDIA GPUs."); + + if (DeviceOffloadingKind == Action::OFK_Cuda) { + CC1Args.push_back("-fcuda-is-device"); + + if (DriverArgs.hasFlag(options::OPT_fcuda_flush_denormals_to_zero, + options::OPT_fno_cuda_flush_denormals_to_zero, false)) + CC1Args.push_back("-fcuda-flush-denormals-to-zero"); + + if (DriverArgs.hasFlag(options::OPT_fcuda_approx_transcendentals, + options::OPT_fno_cuda_approx_transcendentals, false)) + CC1Args.push_back("-fcuda-approx-transcendentals"); + + if (DriverArgs.hasFlag(options::OPT_fgpu_rdc, options::OPT_fno_gpu_rdc, + false)) + CC1Args.push_back("-fgpu-rdc"); + } + + if (DriverArgs.hasArg(options::OPT_nogpulib)) + return; + + std::string LibDeviceFile = CudaInstallation.getLibDeviceFile(GpuArch); + + if (LibDeviceFile.empty()) { + if (DeviceOffloadingKind == Action::OFK_OpenMP && + DriverArgs.hasArg(options::OPT_S)) + return; + + getDriver().Diag(diag::err_drv_no_cuda_libdevice) << GpuArch; + return; + } + + CC1Args.push_back("-mlink-builtin-bitcode"); + CC1Args.push_back(DriverArgs.MakeArgString(LibDeviceFile)); + + // New CUDA versions often introduce new instructions that are only supported + // by new PTX version, so we need to raise PTX level to enable them in NVPTX + // back-end. + const char *PtxFeature = nullptr; + switch(CudaInstallation.version()) { + case CudaVersion::CUDA_101: + PtxFeature = "+ptx64"; + break; + case CudaVersion::CUDA_100: + PtxFeature = "+ptx63"; + break; + case CudaVersion::CUDA_92: + PtxFeature = "+ptx61"; + break; + case CudaVersion::CUDA_91: + PtxFeature = "+ptx61"; + break; + case CudaVersion::CUDA_90: + PtxFeature = "+ptx60"; + break; + default: + PtxFeature = "+ptx42"; + } + CC1Args.append({"-target-feature", PtxFeature}); + if (DriverArgs.hasFlag(options::OPT_fcuda_short_ptr, + options::OPT_fno_cuda_short_ptr, false)) + CC1Args.append({"-mllvm", "--nvptx-short-ptr"}); + + if (CudaInstallation.version() >= CudaVersion::UNKNOWN) + CC1Args.push_back(DriverArgs.MakeArgString( + Twine("-target-sdk-version=") + + CudaVersionToString(CudaInstallation.version()))); + + if (DeviceOffloadingKind == Action::OFK_OpenMP) { + SmallVector<StringRef, 8> LibraryPaths; + if (const Arg *A = DriverArgs.getLastArg(options::OPT_libomptarget_nvptx_path_EQ)) + LibraryPaths.push_back(A->getValue()); + + // Add user defined library paths from LIBRARY_PATH. + llvm::Optional<std::string> LibPath = + llvm::sys::Process::GetEnv("LIBRARY_PATH"); + if (LibPath) { + SmallVector<StringRef, 8> Frags; + const char EnvPathSeparatorStr[] = {llvm::sys::EnvPathSeparator, '\0'}; + llvm::SplitString(*LibPath, Frags, EnvPathSeparatorStr); + for (StringRef Path : Frags) + LibraryPaths.emplace_back(Path.trim()); + } + + // Add path to lib / lib64 folder. + SmallString<256> DefaultLibPath = + llvm::sys::path::parent_path(getDriver().Dir); + llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX); + LibraryPaths.emplace_back(DefaultLibPath.c_str()); + + std::string LibOmpTargetName = + "libomptarget-nvptx-" + GpuArch.str() + ".bc"; + bool FoundBCLibrary = false; + for (StringRef LibraryPath : LibraryPaths) { + SmallString<128> LibOmpTargetFile(LibraryPath); + llvm::sys::path::append(LibOmpTargetFile, LibOmpTargetName); + if (llvm::sys::fs::exists(LibOmpTargetFile)) { + CC1Args.push_back("-mlink-builtin-bitcode"); + CC1Args.push_back(DriverArgs.MakeArgString(LibOmpTargetFile)); + FoundBCLibrary = true; + break; + } + } + if (!FoundBCLibrary) + getDriver().Diag(diag::warn_drv_omp_offload_target_missingbcruntime) + << LibOmpTargetName; + } +} + +bool CudaToolChain::supportsDebugInfoOption(const llvm::opt::Arg *A) const { + const Option &O = A->getOption(); + return (O.matches(options::OPT_gN_Group) && + !O.matches(options::OPT_gmodules)) || + O.matches(options::OPT_g_Flag) || + O.matches(options::OPT_ggdbN_Group) || O.matches(options::OPT_ggdb) || + O.matches(options::OPT_gdwarf) || O.matches(options::OPT_gdwarf_2) || + O.matches(options::OPT_gdwarf_3) || O.matches(options::OPT_gdwarf_4) || + O.matches(options::OPT_gdwarf_5) || + O.matches(options::OPT_gcolumn_info); +} + +void CudaToolChain::adjustDebugInfoKind( + codegenoptions::DebugInfoKind &DebugInfoKind, const ArgList &Args) const { + switch (mustEmitDebugInfo(Args)) { + case DisableDebugInfo: + DebugInfoKind = codegenoptions::NoDebugInfo; + break; + case DebugDirectivesOnly: + DebugInfoKind = codegenoptions::DebugDirectivesOnly; + break; + case EmitSameDebugInfoAsHost: + // Use same debug info level as the host. + break; + } +} + +void CudaToolChain::AddCudaIncludeArgs(const ArgList &DriverArgs, + ArgStringList &CC1Args) const { + // Check our CUDA version if we're going to include the CUDA headers. + if (!DriverArgs.hasArg(options::OPT_nocudainc) && + !DriverArgs.hasArg(options::OPT_no_cuda_version_check)) { + StringRef Arch = DriverArgs.getLastArgValue(options::OPT_march_EQ); + assert(!Arch.empty() && "Must have an explicit GPU arch."); + CudaInstallation.CheckCudaVersionSupportsArch(StringToCudaArch(Arch)); + } + CudaInstallation.AddCudaIncludeArgs(DriverArgs, CC1Args); +} + +llvm::opt::DerivedArgList * +CudaToolChain::TranslateArgs(const llvm::opt::DerivedArgList &Args, + StringRef BoundArch, + Action::OffloadKind DeviceOffloadKind) const { + DerivedArgList *DAL = + HostTC.TranslateArgs(Args, BoundArch, DeviceOffloadKind); + if (!DAL) + DAL = new DerivedArgList(Args.getBaseArgs()); + + const OptTable &Opts = getDriver().getOpts(); + + // For OpenMP device offloading, append derived arguments. Make sure + // flags are not duplicated. + // Also append the compute capability. + if (DeviceOffloadKind == Action::OFK_OpenMP) { + for (Arg *A : Args) { + bool IsDuplicate = false; + for (Arg *DALArg : *DAL) { + if (A == DALArg) { + IsDuplicate = true; + break; + } + } + if (!IsDuplicate) + DAL->append(A); + } + + StringRef Arch = DAL->getLastArgValue(options::OPT_march_EQ); + if (Arch.empty()) + DAL->AddJoinedArg(nullptr, Opts.getOption(options::OPT_march_EQ), + CLANG_OPENMP_NVPTX_DEFAULT_ARCH); + + return DAL; + } + + for (Arg *A : Args) { + if (A->getOption().matches(options::OPT_Xarch__)) { + // Skip this argument unless the architecture matches BoundArch + if (BoundArch.empty() || A->getValue(0) != BoundArch) + continue; + + unsigned Index = Args.getBaseArgs().MakeIndex(A->getValue(1)); + unsigned Prev = Index; + std::unique_ptr<Arg> XarchArg(Opts.ParseOneArg(Args, Index)); + + // If the argument parsing failed or more than one argument was + // consumed, the -Xarch_ argument's parameter tried to consume + // extra arguments. Emit an error and ignore. + // + // We also want to disallow any options which would alter the + // driver behavior; that isn't going to work in our model. We + // use isDriverOption() as an approximation, although things + // like -O4 are going to slip through. + if (!XarchArg || Index > Prev + 1) { + getDriver().Diag(diag::err_drv_invalid_Xarch_argument_with_args) + << A->getAsString(Args); + continue; + } else if (XarchArg->getOption().hasFlag(options::DriverOption)) { + getDriver().Diag(diag::err_drv_invalid_Xarch_argument_isdriver) + << A->getAsString(Args); + continue; + } + XarchArg->setBaseArg(A); + A = XarchArg.release(); + DAL->AddSynthesizedArg(A); + } + DAL->append(A); + } + + if (!BoundArch.empty()) { + DAL->eraseArg(options::OPT_march_EQ); + DAL->AddJoinedArg(nullptr, Opts.getOption(options::OPT_march_EQ), BoundArch); + } + return DAL; +} + +Tool *CudaToolChain::buildAssembler() const { + return new tools::NVPTX::Assembler(*this); +} + +Tool *CudaToolChain::buildLinker() const { + if (OK == Action::OFK_OpenMP) + return new tools::NVPTX::OpenMPLinker(*this); + return new tools::NVPTX::Linker(*this); +} + +void CudaToolChain::addClangWarningOptions(ArgStringList &CC1Args) const { + HostTC.addClangWarningOptions(CC1Args); +} + +ToolChain::CXXStdlibType +CudaToolChain::GetCXXStdlibType(const ArgList &Args) const { + return HostTC.GetCXXStdlibType(Args); +} + +void CudaToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs, + ArgStringList &CC1Args) const { + HostTC.AddClangSystemIncludeArgs(DriverArgs, CC1Args); +} + +void CudaToolChain::AddClangCXXStdlibIncludeArgs(const ArgList &Args, + ArgStringList &CC1Args) const { + HostTC.AddClangCXXStdlibIncludeArgs(Args, CC1Args); +} + +void CudaToolChain::AddIAMCUIncludeArgs(const ArgList &Args, + ArgStringList &CC1Args) const { + HostTC.AddIAMCUIncludeArgs(Args, CC1Args); +} + +SanitizerMask CudaToolChain::getSupportedSanitizers() const { + // The CudaToolChain only supports sanitizers in the sense that it allows + // sanitizer arguments on the command line if they are supported by the host + // toolchain. The CudaToolChain will actually ignore any command line + // arguments for any of these "supported" sanitizers. That means that no + // sanitization of device code is actually supported at this time. + // + // This behavior is necessary because the host and device toolchains + // invocations often share the command line, so the device toolchain must + // tolerate flags meant only for the host toolchain. + return HostTC.getSupportedSanitizers(); +} + +VersionTuple CudaToolChain::computeMSVCVersion(const Driver *D, + const ArgList &Args) const { + return HostTC.computeMSVCVersion(D, Args); +} |
