//===--- PPC.cpp - PPC Helpers for Tools ------------------------*- 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 "PPC.h"

#include "ToolChains/CommonArgs.h"

#include "clang/Driver/Driver.h"

#include "clang/Driver/DriverDiagnostic.h"

#include "clang/Driver/Options.h"

#include "llvm/ADT/StringSwitch.h"

#include "llvm/Option/ArgList.h"

#include "llvm/TargetParser/Host.h"

using namespace clang::driver;

using namespace clang::driver::tools;

using namespace clang;

using namespace llvm::opt;

static std::string getPPCGenericTargetCPU(const llvm::Triple &T) {

  // LLVM may default to generating code for the native CPU,

  // but, like gcc, we default to a more generic option for

  // each architecture. (except on AIX)

  if (T.isOSAIX())

    return "pwr7";

  else if (T.getArch() == llvm::Triple::ppc64le)

    return "ppc64le";

  else if (T.getArch() == llvm::Triple::ppc64)

    return "ppc64";

  else

    return "ppc";

}

static std::string normalizeCPUName(StringRef CPUName, const llvm::Triple &T) {

  // Clang/LLVM does not actually support code generation

  // for the 405 CPU. However, there are uses of this CPU ID

  // in projects that previously used GCC and rely on Clang

  // accepting it. Clang has always ignored it and passed the

  // generic CPU ID to the back end.

  if (CPUName == "generic" || CPUName == "405")

    return getPPCGenericTargetCPU(T);

  if (CPUName == "native") {

    std::string CPU = std::string(llvm::sys::getHostCPUName());

    if (!CPU.empty() && CPU != "generic")

      return CPU;

    else

      return getPPCGenericTargetCPU(T);

  }

  return llvm::StringSwitch<const char *>(CPUName)

      .Case("common", "generic")

      .Case("440fp", "440")

      .Case("630", "pwr3")

      .Case("G3", "g3")

      .Case("G4", "g4")

      .Case("G4+", "g4+")

      .Case("8548", "e500")

      .Case("G5", "g5")

      .Case("power3", "pwr3")

      .Case("power4", "pwr4")

      .Case("power5", "pwr5")

      .Case("power5x", "pwr5x")

      .Case("power6", "pwr6")

      .Case("power6x", "pwr6x")

      .Case("power7", "pwr7")

      .Case("power8", "pwr8")

      .Case("power9", "pwr9")

      .Case("power10", "pwr10")

      .Case("future", "future")

      .Case("powerpc", "ppc")

      .Case("powerpc64", "ppc64")

      .Case("powerpc64le", "ppc64le")

      .Default(CPUName.data());

}

/// Get the (LLVM) name of the PowerPC cpu we are tuning for.

std::string ppc::getPPCTuneCPU(const ArgList &Args, const llvm::Triple &T) {

  if (Arg *A = Args.getLastArg(clang::driver::options::OPT_mtune_EQ))

    return normalizeCPUName(A->getValue(), T);

  return getPPCGenericTargetCPU(T);

}

/// Get the (LLVM) name of the PowerPC cpu we are targeting.

std::string ppc::getPPCTargetCPU(const Driver &D, const ArgList &Args,

                                 const llvm::Triple &T) {

  if (Arg *A = Args.getLastArg(clang::driver::options::OPT_mcpu_EQ))

    return normalizeCPUName(A->getValue(), T);

  return getPPCGenericTargetCPU(T);

}

const char *ppc::getPPCAsmModeForCPU(StringRef Name) {

  return llvm::StringSwitch<const char *>(Name)

      .Case("pwr7", "-mpower7")

      .Case("power7", "-mpower7")

      .Case("pwr8", "-mpower8")

      .Case("power8", "-mpower8")

      .Case("ppc64le", "-mpower8")

      .Case("pwr9", "-mpower9")

      .Case("power9", "-mpower9")

      .Case("pwr10", "-mpower10")

      .Case("power10", "-mpower10")

      .Default("-many");

}

void ppc::getPPCTargetFeatures(const Driver &D, const llvm::Triple &Triple,

                               const ArgList &Args,

                               std::vector<StringRef> &Features) {

  if (Triple.getSubArch() == llvm::Triple::PPCSubArch_spe)

    Features.push_back("+spe");

  handleTargetFeaturesGroup(D, Triple, Args, Features,

                            options::OPT_m_ppc_Features_Group);

  ppc::FloatABI FloatABI = ppc::getPPCFloatABI(D, Args);

  if (FloatABI == ppc::FloatABI::Soft)

    Features.push_back("-hard-float");

  ppc::ReadGOTPtrMode ReadGOT = ppc::getPPCReadGOTPtrMode(D, Triple, Args);

  if (ReadGOT == ppc::ReadGOTPtrMode::SecurePlt)

    Features.push_back("+secure-plt");

}

ppc::ReadGOTPtrMode ppc::getPPCReadGOTPtrMode(const Driver &D, const llvm::Triple &Triple,

                                              const ArgList &Args) {

  if (Args.getLastArg(options::OPT_msecure_plt))

    return ppc::ReadGOTPtrMode::SecurePlt;

  if (Triple.isPPC32SecurePlt())

    return ppc::ReadGOTPtrMode::SecurePlt;

  else

    return ppc::ReadGOTPtrMode::Bss;

}

ppc::FloatABI ppc::getPPCFloatABI(const Driver &D, const ArgList &Args) {

  ppc::FloatABI ABI = ppc::FloatABI::Invalid;

  if (Arg *A =

          Args.getLastArg(options::OPT_msoft_float, options::OPT_mhard_float,

                          options::OPT_mfloat_abi_EQ)) {

    if (A->getOption().matches(options::OPT_msoft_float))

      ABI = ppc::FloatABI::Soft;

    else if (A->getOption().matches(options::OPT_mhard_float))

      ABI = ppc::FloatABI::Hard;

    else {

      ABI = llvm::StringSwitch<ppc::FloatABI>(A->getValue())

                .Case("soft", ppc::FloatABI::Soft)

                .Case("hard", ppc::FloatABI::Hard)

                .Default(ppc::FloatABI::Invalid);

      if (ABI == ppc::FloatABI::Invalid && !StringRef(A->getValue()).empty()) {

        D.Diag(clang::diag::err_drv_invalid_mfloat_abi) << A->getAsString(Args);

        ABI = ppc::FloatABI::Hard;

      }

    }

  }

  // If unspecified, choose the default based on the platform.

  if (ABI == ppc::FloatABI::Invalid) {

    ABI = ppc::FloatABI::Hard;

  }

  return ABI;

}

bool ppc::hasPPCAbiArg(const ArgList &Args, const char *Value) {

  Arg *A = Args.getLastArg(options::OPT_mabi_EQ);

  return A && (A->getValue() == StringRef(Value));

}