//===--- HIPSPV.cpp - HIPSPV ToolChain Implementation -----------*- 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 "HIPSPV.h"

#include "CommonArgs.h"

#include "HIPUtility.h"

#include "clang/Driver/Compilation.h"

#include "clang/Driver/Driver.h"

#include "clang/Driver/DriverDiagnostic.h"

#include "clang/Driver/InputInfo.h"

#include "clang/Driver/Options.h"

#include "llvm/Support/FileSystem.h"

#include "llvm/Support/Path.h"

using namespace clang::driver;

using namespace clang::driver::toolchains;

using namespace clang::driver::tools;

using namespace clang;

using namespace llvm::opt;

// Convenience function for creating temporary file for both modes of

// isSaveTempsEnabled().

static const char *getTempFile(Compilation &C, StringRef Prefix,

                               StringRef Extension) {

  if (C.getDriver().isSaveTempsEnabled()) {

    return C.getArgs().MakeArgString(Prefix + "." + Extension);

  }

  auto TmpFile = C.getDriver().GetTemporaryPath(Prefix, Extension);

  return C.addTempFile(C.getArgs().MakeArgString(TmpFile));

}

// Locates HIP pass plugin.

static std::string findPassPlugin(const Driver &D,

                                  const llvm::opt::ArgList &Args) {

  StringRef Path = Args.getLastArgValue(options::OPT_hipspv_pass_plugin_EQ);

  if (!Path.empty()) {

    if (llvm::sys::fs::exists(Path))

      return Path.str();

    D.Diag(diag::err_drv_no_such_file) << Path;

  }

  StringRef hipPath = Args.getLastArgValue(options::OPT_hip_path_EQ);

  if (!hipPath.empty()) {

    SmallString<128> PluginPath(hipPath);

    llvm::sys::path::append(PluginPath, "lib", "libLLVMHipSpvPasses.so");

    if (llvm::sys::fs::exists(PluginPath))

      return PluginPath.str().str();

    PluginPath.assign(hipPath);

    llvm::sys::path::append(PluginPath, "lib", "llvm",

                            "libLLVMHipSpvPasses.so");

    if (llvm::sys::fs::exists(PluginPath))

      return PluginPath.str().str();

  }

  return std::string();

}

void HIPSPV::Linker::constructLinkAndEmitSpirvCommand(

    Compilation &C, const JobAction &JA, const InputInfoList &Inputs,

    const InputInfo &Output, const llvm::opt::ArgList &Args) const {

  assert(!Inputs.empty() && "Must have at least one input.");

  std::string Name = std::string(llvm::sys::path::stem(Output.getFilename()));

  const char *TempFile = getTempFile(C, Name + "-link", "bc");

  // Link LLVM bitcode.

  ArgStringList LinkArgs{};

  for (auto Input : Inputs)

    LinkArgs.push_back(Input.getFilename());

  LinkArgs.append({"-o", TempFile});

  const char *LlvmLink =

      Args.MakeArgString(getToolChain().GetProgramPath("llvm-link"));

  C.addCommand(std::make_unique<Command>(JA, *this, ResponseFileSupport::None(),

                                         LlvmLink, LinkArgs, Inputs, Output));

  // Post-link HIP lowering.

  // Run LLVM IR passes to lower/expand/emulate HIP code that does not translate

  // to SPIR-V (E.g. dynamic shared memory).

  auto PassPluginPath = findPassPlugin(C.getDriver(), Args);

  if (!PassPluginPath.empty()) {

    const char *PassPathCStr = C.getArgs().MakeArgString(PassPluginPath);

    const char *OptOutput = getTempFile(C, Name + "-lower", "bc");

    ArgStringList OptArgs{TempFile,     "-load-pass-plugin",

                          PassPathCStr, "-passes=hip-post-link-passes",

                          "-o",         OptOutput};

    const char *Opt = Args.MakeArgString(getToolChain().GetProgramPath("opt"));

    C.addCommand(std::make_unique<Command>(

        JA, *this, ResponseFileSupport::None(), Opt, OptArgs, Inputs, Output));

    TempFile = OptOutput;

  }

  // Emit SPIR-V binary.

  llvm::opt::ArgStringList TrArgs{"--spirv-max-version=1.1",

                                  "--spirv-ext=+all"};

  InputInfo TrInput = InputInfo(types::TY_LLVM_BC, TempFile, "");

  SPIRV::constructTranslateCommand(C, *this, JA, Output, TrInput, TrArgs);

}

void HIPSPV::Linker::ConstructJob(Compilation &C, const JobAction &JA,

                                  const InputInfo &Output,

                                  const InputInfoList &Inputs,

                                  const ArgList &Args,

                                  const char *LinkingOutput) const {

  if (Inputs.size() > 0 && Inputs[0].getType() == types::TY_Image &&

      JA.getType() == types::TY_Object)

    return HIP::constructGenerateObjFileFromHIPFatBinary(C, Output, Inputs,

                                                         Args, JA, *this);

  if (JA.getType() == types::TY_HIP_FATBIN)

    return HIP::constructHIPFatbinCommand(C, JA, Output.getFilename(), Inputs,

                                          Args, *this);

  constructLinkAndEmitSpirvCommand(C, JA, Inputs, Output, Args);

}

HIPSPVToolChain::HIPSPVToolChain(const Driver &D, const llvm::Triple &Triple,

                                 const ToolChain &HostTC, const ArgList &Args)

    : ToolChain(D, Triple, Args), HostTC(HostTC) {

  // Lookup binaries into the driver directory, this is used to

  // discover the clang-offload-bundler executable.

  getProgramPaths().push_back(getDriver().Dir);

}

void HIPSPVToolChain::addClangTargetOptions(

    const llvm::opt::ArgList &DriverArgs, llvm::opt::ArgStringList &CC1Args,

    Action::OffloadKind DeviceOffloadingKind) const {

  HostTC.addClangTargetOptions(DriverArgs, CC1Args, DeviceOffloadingKind);

  assert(DeviceOffloadingKind == Action::OFK_HIP &&

         "Only HIP offloading kinds are supported for GPUs.");

  CC1Args.append(

      {"-fcuda-is-device", "-fcuda-allow-variadic-functions",

       // A crude workaround for llvm-spirv which does not handle the

       // autovectorized code well (vector reductions, non-i{8,16,32,64} types).

       // TODO: Allow autovectorization when SPIR-V backend arrives.

       "-mllvm", "-vectorize-loops=false", "-mllvm", "-vectorize-slp=false"});

  // Default to "hidden" visibility, as object level linking will not be

  // supported for the foreseeable future.

  if (!DriverArgs.hasArg(options::OPT_fvisibility_EQ,

                         options::OPT_fvisibility_ms_compat))

    CC1Args.append(

        {"-fvisibility=hidden", "-fapply-global-visibility-to-externs"});

  llvm::for_each(getDeviceLibs(DriverArgs),

                 [&](const BitCodeLibraryInfo &BCFile) {

                   CC1Args.append({"-mlink-builtin-bitcode",

                                   DriverArgs.MakeArgString(BCFile.Path)});

                 });

}

Tool *HIPSPVToolChain::buildLinker() const {

  assert(getTriple().getArch() == llvm::Triple::spirv64);

  return new tools::HIPSPV::Linker(*this);

}

void HIPSPVToolChain::addClangWarningOptions(ArgStringList &CC1Args) const {

  HostTC.addClangWarningOptions(CC1Args);

}

ToolChain::CXXStdlibType

HIPSPVToolChain::GetCXXStdlibType(const ArgList &Args) const {

  return HostTC.GetCXXStdlibType(Args);

}

void HIPSPVToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,

                                                ArgStringList &CC1Args) const {

  HostTC.AddClangSystemIncludeArgs(DriverArgs, CC1Args);

}

void HIPSPVToolChain::AddClangCXXStdlibIncludeArgs(

    const ArgList &Args, ArgStringList &CC1Args) const {

  HostTC.AddClangCXXStdlibIncludeArgs(Args, CC1Args);

}

void HIPSPVToolChain::AddIAMCUIncludeArgs(const ArgList &Args,

                                          ArgStringList &CC1Args) const {

  HostTC.AddIAMCUIncludeArgs(Args, CC1Args);

}

void HIPSPVToolChain::AddHIPIncludeArgs(const ArgList &DriverArgs,

                                        ArgStringList &CC1Args) const {

  if (DriverArgs.hasArg(options::OPT_nogpuinc))

    return;

  StringRef hipPath = DriverArgs.getLastArgValue(options::OPT_hip_path_EQ);

  if (hipPath.empty()) {

    getDriver().Diag(diag::err_drv_hipspv_no_hip_path) << 1 << "'-nogpuinc'";

    return;

  }

  SmallString<128> P(hipPath);

  llvm::sys::path::append(P, "include");

  CC1Args.append({"-isystem", DriverArgs.MakeArgString(P)});

}

llvm::SmallVector<ToolChain::BitCodeLibraryInfo, 12>

HIPSPVToolChain::getDeviceLibs(const llvm::opt::ArgList &DriverArgs) const {

  llvm::SmallVector<ToolChain::BitCodeLibraryInfo, 12> BCLibs;

  if (DriverArgs.hasArg(options::OPT_nogpulib))

    return {};

  ArgStringList LibraryPaths;

  // Find device libraries in --hip-device-lib-path and HIP_DEVICE_LIB_PATH.

  auto HipDeviceLibPathArgs = DriverArgs.getAllArgValues(

      // --hip-device-lib-path is alias to this option.

      clang::driver::options::OPT_rocm_device_lib_path_EQ);

  for (auto Path : HipDeviceLibPathArgs)

    LibraryPaths.push_back(DriverArgs.MakeArgString(Path));

  StringRef HipPath = DriverArgs.getLastArgValue(options::OPT_hip_path_EQ);

  if (!HipPath.empty()) {

    SmallString<128> Path(HipPath);

    llvm::sys::path::append(Path, "lib", "hip-device-lib");

    LibraryPaths.push_back(DriverArgs.MakeArgString(Path));

  }

  addDirectoryList(DriverArgs, LibraryPaths, "", "HIP_DEVICE_LIB_PATH");

  // Maintain compatability with --hip-device-lib.

  auto BCLibArgs = DriverArgs.getAllArgValues(options::OPT_hip_device_lib_EQ);

  if (!BCLibArgs.empty()) {

    llvm::for_each(BCLibArgs, [&](StringRef BCName) {

      StringRef FullName;

      for (std::string LibraryPath : LibraryPaths) {

        SmallString<128> Path(LibraryPath);

        llvm::sys::path::append(Path, BCName);

        FullName = Path;

        if (llvm::sys::fs::exists(FullName)) {

          BCLibs.emplace_back(FullName.str());

          return;

        }

      }

      getDriver().Diag(diag::err_drv_no_such_file) << BCName;

    });

  } else {

    // Search device library named as 'hipspv-<triple>.bc'.

    auto TT = getTriple().normalize();

    std::string BCName = "hipspv-" + TT + ".bc";

    for (auto *LibPath : LibraryPaths) {

      SmallString<128> Path(LibPath);

      llvm::sys::path::append(Path, BCName);

      if (llvm::sys::fs::exists(Path)) {

        BCLibs.emplace_back(Path.str().str());

        return BCLibs;

      }

    }

    getDriver().Diag(diag::err_drv_no_hipspv_device_lib)

        << 1 << ("'" + TT + "' target");

    return {};

  }

  return BCLibs;

}

SanitizerMask HIPSPVToolChain::getSupportedSanitizers() const {

  // The HIPSPVToolChain only supports sanitizers in the sense that it allows

  // sanitizer arguments on the command line if they are supported by the host

  // toolchain. The HIPSPVToolChain 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 HIPSPVToolChain::computeMSVCVersion(const Driver *D,

                                                 const ArgList &Args) const {

  return HostTC.computeMSVCVersion(D, Args);

}

void HIPSPVToolChain::adjustDebugInfoKind(

    llvm::codegenoptions::DebugInfoKind &DebugInfoKind,

    const llvm::opt::ArgList &Args) const {

  // Debug info generation is disabled for SPIRV-LLVM-Translator

  // which currently aborts on the presence of DW_OP_LLVM_convert.

  // TODO: Enable debug info when the SPIR-V backend arrives.

  DebugInfoKind = llvm::codegenoptions::NoDebugInfo;

}