clang/lib/Basic/Targets.cpp

//===--- Targets.cpp - Implement target feature support -------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements construction of a TargetInfo object from a
// target triple.
//
//===----------------------------------------------------------------------===//

#include "Targets.h"

#include "Targets/AArch64.h"
#include "Targets/AMDGPU.h"
#include "Targets/ARM.h"
#include "Targets/AVR.h"
#include "Targets/BPF.h"
#include "Targets/Hexagon.h"
#include "Targets/Lanai.h"
#include "Targets/Le64.h"
#include "Targets/MSP430.h"
#include "Targets/Mips.h"
#include "Targets/NVPTX.h"
#include "Targets/Nios2.h"
#include "Targets/OSTargets.h"
#include "Targets/PNaCl.h"
#include "Targets/PPC.h"
#include "Targets/SPIR.h"
#include "Targets/Sparc.h"
#include "Targets/SystemZ.h"
#include "Targets/TCE.h"
#include "Targets/WebAssembly.h"
#include "Targets/X86.h"
#include "Targets/XCore.h"
#include "clang/Basic/Diagnostic.h"
#include "llvm/ADT/Triple.h"

using namespace clang;

namespace clang {
namespace targets {
//===----------------------------------------------------------------------===//
//  Common code shared among targets.
//===----------------------------------------------------------------------===//

/// DefineStd - Define a macro name and standard variants.  For example if
/// MacroName is "unix", then this will define "__unix", "__unix__", and "unix"
/// when in GNU mode.
void DefineStd(MacroBuilder &Builder, StringRef MacroName,
               const LangOptions &Opts) {
  assert(MacroName[0] != '_' && "Identifier should be in the user's namespace");

  // If in GNU mode (e.g. -std=gnu99 but not -std=c99) define the raw identifier
  // in the user's namespace.
  if (Opts.GNUMode)
    Builder.defineMacro(MacroName);

  // Define __unix.
  Builder.defineMacro("__" + MacroName);

  // Define __unix__.
  Builder.defineMacro("__" + MacroName + "__");
}

void defineCPUMacros(MacroBuilder &Builder, StringRef CPUName, bool Tuning) {
  Builder.defineMacro("__" + CPUName);
  Builder.defineMacro("__" + CPUName + "__");
  if (Tuning)
    Builder.defineMacro("__tune_" + CPUName + "__");
}

void addMinGWDefines(const LangOptions &Opts, MacroBuilder &Builder) {
  Builder.defineMacro("__MSVCRT__");
  Builder.defineMacro("__MINGW32__");
  addCygMingDefines(Opts, Builder);
}

//===----------------------------------------------------------------------===//
// Driver code
//===----------------------------------------------------------------------===//

TargetInfo *AllocateTarget(const llvm::Triple &Triple,
                           const TargetOptions &Opts) {
  llvm::Triple::OSType os = Triple.getOS();

  switch (Triple.getArch()) {
  default:
    return nullptr;

  case llvm::Triple::xcore:
    return new XCoreTargetInfo(Triple, Opts);

  case llvm::Triple::hexagon:
    return new HexagonTargetInfo(Triple, Opts);

  case llvm::Triple::lanai:
    return new LanaiTargetInfo(Triple, Opts);

  case llvm::Triple::aarch64:
    if (Triple.isOSDarwin())
      return new DarwinAArch64TargetInfo(Triple, Opts);

    switch (os) {
    case llvm::Triple::CloudABI:
      return new CloudABITargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::Fuchsia:
      return new FuchsiaTargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<AArch64leTargetInfo>(Triple, Opts);
    case llvm::Triple::Win32:
      return new MicrosoftARM64TargetInfo(Triple, Opts);
    default:
      return new AArch64leTargetInfo(Triple, Opts);
    }

  case llvm::Triple::aarch64_be:
    switch (os) {
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<AArch64beTargetInfo>(Triple, Opts);
    case llvm::Triple::Fuchsia:
      return new FuchsiaTargetInfo<AArch64beTargetInfo>(Triple, Opts);
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<AArch64beTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<AArch64beTargetInfo>(Triple, Opts);
    default:
      return new AArch64beTargetInfo(Triple, Opts);
    }

  case llvm::Triple::arm:
  case llvm::Triple::thumb:
    if (Triple.isOSBinFormatMachO())
      return new DarwinARMTargetInfo(Triple, Opts);

    switch (os) {
    case llvm::Triple::CloudABI:
      return new CloudABITargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::Bitrig:
      return new BitrigTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<ARMleTargetInfo>(Triple, Opts);
    case llvm::Triple::Win32:
      switch (Triple.getEnvironment()) {
      case llvm::Triple::Cygnus:
        return new CygwinARMTargetInfo(Triple, Opts);
      case llvm::Triple::GNU:
        return new MinGWARMTargetInfo(Triple, Opts);
      case llvm::Triple::Itanium:
        return new ItaniumWindowsARMleTargetInfo(Triple, Opts);
      case llvm::Triple::MSVC:
      default: // Assume MSVC for unknown environments
        return new MicrosoftARMleTargetInfo(Triple, Opts);
      }
    default:
      return new ARMleTargetInfo(Triple, Opts);
    }

  case llvm::Triple::armeb:
  case llvm::Triple::thumbeb:
    if (Triple.isOSDarwin())
      return new DarwinARMTargetInfo(Triple, Opts);

    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::Bitrig:
      return new BitrigTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<ARMbeTargetInfo>(Triple, Opts);
    default:
      return new ARMbeTargetInfo(Triple, Opts);
    }

  case llvm::Triple::avr:
    return new AVRTargetInfo(Triple, Opts);
  case llvm::Triple::bpfeb:
  case llvm::Triple::bpfel:
    return new BPFTargetInfo(Triple, Opts);

  case llvm::Triple::msp430:
    return new MSP430TargetInfo(Triple, Opts);

  case llvm::Triple::nios2:
    return new LinuxTargetInfo<Nios2TargetInfo>(Triple, Opts);

  case llvm::Triple::mips:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    default:
      return new MipsTargetInfo(Triple, Opts);
    }

  case llvm::Triple::mipsel:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<NaClMips32TargetInfo>(Triple, Opts);
    default:
      return new MipsTargetInfo(Triple, Opts);
    }

  case llvm::Triple::mips64:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    default:
      return new MipsTargetInfo(Triple, Opts);
    }

  case llvm::Triple::mips64el:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<MipsTargetInfo>(Triple, Opts);
    default:
      return new MipsTargetInfo(Triple, Opts);
    }

  case llvm::Triple::le32:
    switch (os) {
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<PNaClTargetInfo>(Triple, Opts);
    default:
      return nullptr;
    }

  case llvm::Triple::le64:
    return new Le64TargetInfo(Triple, Opts);

  case llvm::Triple::ppc:
    if (Triple.isOSDarwin())
      return new DarwinPPC32TargetInfo(Triple, Opts);
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<PPC32TargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<PPC32TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<PPC32TargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<PPC32TargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<PPC32TargetInfo>(Triple, Opts);
    default:
      return new PPC32TargetInfo(Triple, Opts);
    }

  case llvm::Triple::ppc64:
    if (Triple.isOSDarwin())
      return new DarwinPPC64TargetInfo(Triple, Opts);
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<PPC64TargetInfo>(Triple, Opts);
    case llvm::Triple::Lv2:
      return new PS3PPUTargetInfo<PPC64TargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<PPC64TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<PPC64TargetInfo>(Triple, Opts);
    default:
      return new PPC64TargetInfo(Triple, Opts);
    }

  case llvm::Triple::ppc64le:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<PPC64TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<PPC64TargetInfo>(Triple, Opts);
    default:
      return new PPC64TargetInfo(Triple, Opts);
    }

  case llvm::Triple::nvptx:
    return new NVPTXTargetInfo(Triple, Opts, /*TargetPointerWidth=*/32);
  case llvm::Triple::nvptx64:
    return new NVPTXTargetInfo(Triple, Opts, /*TargetPointerWidth=*/64);

  case llvm::Triple::amdgcn:
  case llvm::Triple::r600:
    return new AMDGPUTargetInfo(Triple, Opts);

  case llvm::Triple::sparc:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<SparcV8TargetInfo>(Triple, Opts);
    case llvm::Triple::Solaris:
      return new SolarisTargetInfo<SparcV8TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<SparcV8TargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<SparcV8TargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<SparcV8TargetInfo>(Triple, Opts);
    default:
      return new SparcV8TargetInfo(Triple, Opts);
    }

  // The 'sparcel' architecture copies all the above cases except for Solaris.
  case llvm::Triple::sparcel:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<SparcV8elTargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<SparcV8elTargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<SparcV8elTargetInfo>(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSTargetInfo<SparcV8elTargetInfo>(Triple, Opts);
    default:
      return new SparcV8elTargetInfo(Triple, Opts);
    }

  case llvm::Triple::sparcv9:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<SparcV9TargetInfo>(Triple, Opts);
    case llvm::Triple::Solaris:
      return new SolarisTargetInfo<SparcV9TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<SparcV9TargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDTargetInfo<SparcV9TargetInfo>(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<SparcV9TargetInfo>(Triple, Opts);
    default:
      return new SparcV9TargetInfo(Triple, Opts);
    }

  case llvm::Triple::systemz:
    switch (os) {
    case llvm::Triple::Linux:
      return new LinuxTargetInfo<SystemZTargetInfo>(Triple, Opts);
    default:
      return new SystemZTargetInfo(Triple, Opts);
    }

  case llvm::Triple::tce:
    return new TCETargetInfo(Triple, Opts);

  case llvm::Triple::tcele:
    return new TCELETargetInfo(Triple, Opts);

  case llvm::Triple::x86:
    if (Triple.isOSDarwin())
      return new DarwinI386TargetInfo(Triple, Opts);

    switch (os) {
    case llvm::Triple::Ananas:
      return new AnanasTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::CloudABI:
      return new CloudABITargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::Linux: {
      switch (Triple.getEnvironment()) {
      default:
        return new LinuxTargetInfo<X86_32TargetInfo>(Triple, Opts);
      case llvm::Triple::Android:
        return new AndroidX86_32TargetInfo(Triple, Opts);
      }
    }
    case llvm::Triple::DragonFly:
      return new DragonFlyBSDTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDI386TargetInfo(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDI386TargetInfo(Triple, Opts);
    case llvm::Triple::Bitrig:
      return new BitrigI386TargetInfo(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::KFreeBSD:
      return new KFreeBSDTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::Minix:
      return new MinixTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::Solaris:
      return new SolarisTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::Win32: {
      switch (Triple.getEnvironment()) {
      case llvm::Triple::Cygnus:
        return new CygwinX86_32TargetInfo(Triple, Opts);
      case llvm::Triple::GNU:
        return new MinGWX86_32TargetInfo(Triple, Opts);
      case llvm::Triple::Itanium:
      case llvm::Triple::MSVC:
      default: // Assume MSVC for unknown environments
        return new MicrosoftX86_32TargetInfo(Triple, Opts);
      }
    }
    case llvm::Triple::Haiku:
      return new HaikuX86_32TargetInfo(Triple, Opts);
    case llvm::Triple::RTEMS:
      return new RTEMSX86_32TargetInfo(Triple, Opts);
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<X86_32TargetInfo>(Triple, Opts);
    case llvm::Triple::ELFIAMCU:
      return new MCUX86_32TargetInfo(Triple, Opts);
    default:
      return new X86_32TargetInfo(Triple, Opts);
    }

  case llvm::Triple::x86_64:
    if (Triple.isOSDarwin() || Triple.isOSBinFormatMachO())
      return new DarwinX86_64TargetInfo(Triple, Opts);

    switch (os) {
    case llvm::Triple::Ananas:
      return new AnanasTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::CloudABI:
      return new CloudABITargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::Linux: {
      switch (Triple.getEnvironment()) {
      default:
        return new LinuxTargetInfo<X86_64TargetInfo>(Triple, Opts);
      case llvm::Triple::Android:
        return new AndroidX86_64TargetInfo(Triple, Opts);
      }
    }
    case llvm::Triple::DragonFly:
      return new DragonFlyBSDTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::NetBSD:
      return new NetBSDTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::OpenBSD:
      return new OpenBSDX86_64TargetInfo(Triple, Opts);
    case llvm::Triple::Bitrig:
      return new BitrigX86_64TargetInfo(Triple, Opts);
    case llvm::Triple::FreeBSD:
      return new FreeBSDTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::Fuchsia:
      return new FuchsiaTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::KFreeBSD:
      return new KFreeBSDTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::Solaris:
      return new SolarisTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::Win32: {
      switch (Triple.getEnvironment()) {
      case llvm::Triple::Cygnus:
        return new CygwinX86_64TargetInfo(Triple, Opts);
      case llvm::Triple::GNU:
        return new MinGWX86_64TargetInfo(Triple, Opts);
      case llvm::Triple::MSVC:
      default: // Assume MSVC for unknown environments
        return new MicrosoftX86_64TargetInfo(Triple, Opts);
      }
    }
    case llvm::Triple::Haiku:
      return new HaikuTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::NaCl:
      return new NaClTargetInfo<X86_64TargetInfo>(Triple, Opts);
    case llvm::Triple::PS4:
      return new PS4OSTargetInfo<X86_64TargetInfo>(Triple, Opts);
    default:
      return new X86_64TargetInfo(Triple, Opts);
    }

  case llvm::Triple::spir: {
    if (Triple.getOS() != llvm::Triple::UnknownOS ||
        Triple.getEnvironment() != llvm::Triple::UnknownEnvironment)
      return nullptr;
    return new SPIR32TargetInfo(Triple, Opts);
  }
  case llvm::Triple::spir64: {
    if (Triple.getOS() != llvm::Triple::UnknownOS ||
        Triple.getEnvironment() != llvm::Triple::UnknownEnvironment)
      return nullptr;
    return new SPIR64TargetInfo(Triple, Opts);
  }
  case llvm::Triple::wasm32:
    if (Triple.getSubArch() != llvm::Triple::NoSubArch ||
        Triple.getVendor() != llvm::Triple::UnknownVendor ||
        Triple.getOS() != llvm::Triple::UnknownOS ||
        Triple.getEnvironment() != llvm::Triple::UnknownEnvironment ||
        !(Triple.isOSBinFormatELF() || Triple.isOSBinFormatWasm()))
      return nullptr;
    return new WebAssemblyOSTargetInfo<WebAssembly32TargetInfo>(Triple, Opts);
  case llvm::Triple::wasm64:
    if (Triple.getSubArch() != llvm::Triple::NoSubArch ||
        Triple.getVendor() != llvm::Triple::UnknownVendor ||
        Triple.getOS() != llvm::Triple::UnknownOS ||
        Triple.getEnvironment() != llvm::Triple::UnknownEnvironment ||
        !(Triple.isOSBinFormatELF() || Triple.isOSBinFormatWasm()))
      return nullptr;
    return new WebAssemblyOSTargetInfo<WebAssembly64TargetInfo>(Triple, Opts);

  case llvm::Triple::renderscript32:
    return new LinuxTargetInfo<RenderScript32TargetInfo>(Triple, Opts);
  case llvm::Triple::renderscript64:
    return new LinuxTargetInfo<RenderScript64TargetInfo>(Triple, Opts);
  }
}
} // namespace targets
} // namespace clang

using namespace clang::targets;
/// CreateTargetInfo - Return the target info object for the specified target
/// options.
TargetInfo *
TargetInfo::CreateTargetInfo(DiagnosticsEngine &Diags,
                             const std::shared_ptr<TargetOptions> &Opts) {
  llvm::Triple Triple(Opts->Triple);

  // Construct the target
  std::unique_ptr<TargetInfo> Target(AllocateTarget(Triple, *Opts));
  if (!Target) {
    Diags.Report(diag::err_target_unknown_triple) << Triple.str();
    return nullptr;
  }
  Target->TargetOpts = Opts;

  // Set the target CPU if specified.
  if (!Opts->CPU.empty() && !Target->setCPU(Opts->CPU)) {
    Diags.Report(diag::err_target_unknown_cpu) << Opts->CPU;
    return nullptr;
  }

  // Set the target ABI if specified.
  if (!Opts->ABI.empty() && !Target->setABI(Opts->ABI)) {
    Diags.Report(diag::err_target_unknown_abi) << Opts->ABI;
    return nullptr;
  }

  // Set the fp math unit.
  if (!Opts->FPMath.empty() && !Target->setFPMath(Opts->FPMath)) {
    Diags.Report(diag::err_target_unknown_fpmath) << Opts->FPMath;
    return nullptr;
  }

  // Compute the default target features, we need the target to handle this
  // because features may have dependencies on one another.
  llvm::StringMap<bool> Features;
  if (!Target->initFeatureMap(Features, Diags, Opts->CPU,
                              Opts->FeaturesAsWritten))
    return nullptr;

  // Add the features to the compile options.
  Opts->Features.clear();
  for (const auto &F : Features)
    Opts->Features.push_back((F.getValue() ? "+" : "-") + F.getKey().str());

  if (!Target->handleTargetFeatures(Opts->Features, Diags))
    return nullptr;

  Target->setSupportedOpenCLOpts();
  Target->setOpenCLExtensionOpts();

  if (!Target->validateTarget(Diags))
    return nullptr;

  return Target.release();
}