//===-- llvm/ADT/Triple.h - Target triple helper class ----------*- 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
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_ADT_TRIPLE_H
#define LLVM_ADT_TRIPLE_H

#include "llvm/ADT/Twine.h"

// Some system headers or GCC predefined macros conflict with identifiers in
// this file.  Undefine them here.
#undef NetBSD
#undef mips
#undef sparc

namespace llvm {

/// Triple - Helper class for working with autoconf configuration names. For
/// historical reasons, we also call these 'triples' (they used to contain
/// exactly three fields).
///
/// Configuration names are strings in the canonical form:
///   ARCHITECTURE-VENDOR-OPERATING_SYSTEM
/// or
///   ARCHITECTURE-VENDOR-OPERATING_SYSTEM-ENVIRONMENT
///
/// This class is used for clients which want to support arbitrary
/// configuration names, but also want to implement certain special
/// behavior for particular configurations. This class isolates the mapping
/// from the components of the configuration name to well known IDs.
///
/// At its core the Triple class is designed to be a wrapper for a triple
/// string; the constructor does not change or normalize the triple string.
/// Clients that need to handle the non-canonical triples that users often
/// specify should use the normalize method.
///
/// See autoconf/config.guess for a glimpse into what configuration names
/// look like in practice.
class Triple {
public:
  enum ArchType {
    UnknownArch,

    arm,            // ARM (little endian): arm, armv.*, xscale
    armeb,          // ARM (big endian): armeb
    aarch64,        // AArch64 (little endian): aarch64
    aarch64_be,     // AArch64 (big endian): aarch64_be
    aarch64_32,     // AArch64 (little endian) ILP32: aarch64_32
    arc,            // ARC: Synopsys ARC
    avr,            // AVR: Atmel AVR microcontroller
    bpfel,          // eBPF or extended BPF or 64-bit BPF (little endian)
    bpfeb,          // eBPF or extended BPF or 64-bit BPF (big endian)
    hexagon,        // Hexagon: hexagon
    mips,           // MIPS: mips, mipsallegrex, mipsr6
    mipsel,         // MIPSEL: mipsel, mipsallegrexe, mipsr6el
    mips64,         // MIPS64: mips64, mips64r6, mipsn32, mipsn32r6
    mips64el,       // MIPS64EL: mips64el, mips64r6el, mipsn32el, mipsn32r6el
    msp430,         // MSP430: msp430
    ppc,            // PPC: powerpc
    ppc64,          // PPC64: powerpc64, ppu
    ppc64le,        // PPC64LE: powerpc64le
    r600,           // R600: AMD GPUs HD2XXX - HD6XXX
    amdgcn,         // AMDGCN: AMD GCN GPUs
    riscv32,        // RISC-V (32-bit): riscv32
    riscv64,        // RISC-V (64-bit): riscv64
    sparc,          // Sparc: sparc
    sparcv9,        // Sparcv9: Sparcv9
    sparcel,        // Sparc: (endianness = little). NB: 'Sparcle' is a CPU variant
    systemz,        // SystemZ: s390x
    tce,            // TCE (http://tce.cs.tut.fi/): tce
    tcele,          // TCE little endian (http://tce.cs.tut.fi/): tcele
    thumb,          // Thumb (little endian): thumb, thumbv.*
    thumbeb,        // Thumb (big endian): thumbeb
    x86,            // X86: i[3-9]86
    x86_64,         // X86-64: amd64, x86_64
    xcore,          // XCore: xcore
    nvptx,          // NVPTX: 32-bit
    nvptx64,        // NVPTX: 64-bit
    le32,           // le32: generic little-endian 32-bit CPU (PNaCl)
    le64,           // le64: generic little-endian 64-bit CPU (PNaCl)
    amdil,          // AMDIL
    amdil64,        // AMDIL with 64-bit pointers
    hsail,          // AMD HSAIL
    hsail64,        // AMD HSAIL with 64-bit pointers
    spir,           // SPIR: standard portable IR for OpenCL 32-bit version
    spir64,         // SPIR: standard portable IR for OpenCL 64-bit version
    kalimba,        // Kalimba: generic kalimba
    shave,          // SHAVE: Movidius vector VLIW processors
    lanai,          // Lanai: Lanai 32-bit
    wasm32,         // WebAssembly with 32-bit pointers
    wasm64,         // WebAssembly with 64-bit pointers
    renderscript32, // 32-bit RenderScript
    renderscript64, // 64-bit RenderScript
    LastArchType = renderscript64
  };
  enum SubArchType {
    NoSubArch,

    ARMSubArch_v8_5a,
    ARMSubArch_v8_4a,
    ARMSubArch_v8_3a,
    ARMSubArch_v8_2a,
    ARMSubArch_v8_1a,
    ARMSubArch_v8,
    ARMSubArch_v8r,
    ARMSubArch_v8m_baseline,
    ARMSubArch_v8m_mainline,
    ARMSubArch_v8_1m_mainline,
    ARMSubArch_v7,
    ARMSubArch_v7em,
    ARMSubArch_v7m,
    ARMSubArch_v7s,
    ARMSubArch_v7k,
    ARMSubArch_v7ve,
    ARMSubArch_v6,
    ARMSubArch_v6m,
    ARMSubArch_v6k,
    ARMSubArch_v6t2,
    ARMSubArch_v5,
    ARMSubArch_v5te,
    ARMSubArch_v4t,

    KalimbaSubArch_v3,
    KalimbaSubArch_v4,
    KalimbaSubArch_v5,

    MipsSubArch_r6
  };
  enum VendorType {
    UnknownVendor,

    Apple,
    PC,
    SCEI,
    BGP,
    BGQ,
    Freescale,
    IBM,
    ImaginationTechnologies,
    MipsTechnologies,
    NVIDIA,
    CSR,
    Myriad,
    AMD,
    Mesa,
    SUSE,
    OpenEmbedded,
    LastVendorType = OpenEmbedded
  };
  enum OSType {
    UnknownOS,

    Ananas,
    CloudABI,
    Darwin,
    DragonFly,
    FreeBSD,
    Fuchsia,
    IOS,
    KFreeBSD,
    Linux,
    Lv2,        // PS3
    MacOSX,
    NetBSD,
    OpenBSD,
    Solaris,
    Win32,
    Haiku,
    Minix,
    RTEMS,
    NaCl,       // Native Client
    CNK,        // BG/P Compute-Node Kernel
    AIX,
    CUDA,       // NVIDIA CUDA
    NVCL,       // NVIDIA OpenCL
    AMDHSA,     // AMD HSA Runtime
    PS4,
    ELFIAMCU,
    TvOS,       // Apple tvOS
    WatchOS,    // Apple watchOS
    Mesa3D,
    Contiki,
    AMDPAL,     // AMD PAL Runtime
    HermitCore, // HermitCore Unikernel/Multikernel
    Hurd,       // GNU/Hurd
    WASI,       // Experimental WebAssembly OS
    Emscripten,
    LastOSType = Emscripten
  };
  enum EnvironmentType {
    UnknownEnvironment,

    GNU,
    GNUABIN32,
    GNUABI64,
    GNUEABI,
    GNUEABIHF,
    GNUX32,
    CODE16,
    EABI,
    EABIHF,
    ELFv1,
    ELFv2,
    Android,
    Musl,
    MuslEABI,
    MuslEABIHF,

    MSVC,
    Itanium,
    Cygnus,
    CoreCLR,
    Simulator, // Simulator variants of other systems, e.g., Apple's iOS
    MacABI, // Mac Catalyst variant of Apple's iOS deployment target.
    LastEnvironmentType = MacABI
  };
  enum ObjectFormatType {
    UnknownObjectFormat,

    COFF,
    ELF,
    MachO,
    Wasm,
    XCOFF,
  };

private:
  std::string Data;

  /// The parsed arch type.
  ArchType Arch;

  /// The parsed subarchitecture type.
  SubArchType SubArch;

  /// The parsed vendor type.
  VendorType Vendor;

  /// The parsed OS type.
  OSType OS;

  /// The parsed Environment type.
  EnvironmentType Environment;

  /// The object format type.
  ObjectFormatType ObjectFormat;

public:
  /// @name Constructors
  /// @{

  /// Default constructor is the same as an empty string and leaves all
  /// triple fields unknown.
  Triple()
      : Data(), Arch(), SubArch(), Vendor(), OS(), Environment(),
        ObjectFormat() {}

  explicit Triple(const Twine &Str);
  Triple(const Twine &ArchStr, const Twine &VendorStr, const Twine &OSStr);
  Triple(const Twine &ArchStr, const Twine &VendorStr, const Twine &OSStr,
         const Twine &EnvironmentStr);

  bool operator==(const Triple &Other) const {
    return Arch == Other.Arch && SubArch == Other.SubArch &&
           Vendor == Other.Vendor && OS == Other.OS &&
           Environment == Other.Environment &&
           ObjectFormat == Other.ObjectFormat;
  }

  bool operator!=(const Triple &Other) const {
    return !(*this == Other);
  }

  /// @}
  /// @name Normalization
  /// @{

  /// normalize - Turn an arbitrary machine specification into the canonical
  /// triple form (or something sensible that the Triple class understands if
  /// nothing better can reasonably be done).  In particular, it handles the
  /// common case in which otherwise valid components are in the wrong order.
  static std::string normalize(StringRef Str);

  /// Return the normalized form of this triple's string.
  std::string normalize() const { return normalize(Data); }

  /// @}
  /// @name Typed Component Access
  /// @{

  /// getArch - Get the parsed architecture type of this triple.
  ArchType getArch() const { return Arch; }

  /// getSubArch - get the parsed subarchitecture type for this triple.
  SubArchType getSubArch() const { return SubArch; }

  /// getVendor - Get the parsed vendor type of this triple.
  VendorType getVendor() const { return Vendor; }

  /// getOS - Get the parsed operating system type of this triple.
  OSType getOS() const { return OS; }

  /// hasEnvironment - Does this triple have the optional environment
  /// (fourth) component?
  bool hasEnvironment() const {
    return getEnvironmentName() != "";
  }

  /// getEnvironment - Get the parsed environment type of this triple.
  EnvironmentType getEnvironment() const { return Environment; }

  /// Parse the version number from the OS name component of the
  /// triple, if present.
  ///
  /// For example, "fooos1.2.3" would return (1, 2, 3).
  ///
  /// If an entry is not defined, it will be returned as 0.
  void getEnvironmentVersion(unsigned &Major, unsigned &Minor,
                             unsigned &Micro) const;

  /// getFormat - Get the object format for this triple.
  ObjectFormatType getObjectFormat() const { return ObjectFormat; }

  /// getOSVersion - Parse the version number from the OS name component of the
  /// triple, if present.
  ///
  /// For example, "fooos1.2.3" would return (1, 2, 3).
  ///
  /// If an entry is not defined, it will be returned as 0.
  void getOSVersion(unsigned &Major, unsigned &Minor, unsigned &Micro) const;

  /// getOSMajorVersion - Return just the major version number, this is
  /// specialized because it is a common query.
  unsigned getOSMajorVersion() const {
    unsigned Maj, Min, Micro;
    getOSVersion(Maj, Min, Micro);
    return Maj;
  }

  /// getMacOSXVersion - Parse the version number as with getOSVersion and then
  /// translate generic "darwin" versions to the corresponding OS X versions.
  /// This may also be called with IOS triples but the OS X version number is
  /// just set to a constant 10.4.0 in that case.  Returns true if successful.
  bool getMacOSXVersion(unsigned &Major, unsigned &Minor,
                        unsigned &Micro) const;

  /// getiOSVersion - Parse the version number as with getOSVersion.  This should
  /// only be called with IOS or generic triples.
  void getiOSVersion(unsigned &Major, unsigned &Minor,
                     unsigned &Micro) const;

  /// getWatchOSVersion - Parse the version number as with getOSVersion.  This
  /// should only be called with WatchOS or generic triples.
  void getWatchOSVersion(unsigned &Major, unsigned &Minor,
                         unsigned &Micro) const;

  /// @}
  /// @name Direct Component Access
  /// @{

  const std::string &str() const { return Data; }

  const std::string &getTriple() const { return Data; }

  /// getArchName - Get the architecture (first) component of the
  /// triple.
  StringRef getArchName() const;

  /// getVendorName - Get the vendor (second) component of the triple.
  StringRef getVendorName() const;

  /// getOSName - Get the operating system (third) component of the
  /// triple.
  StringRef getOSName() const;

  /// getEnvironmentName - Get the optional environment (fourth)
  /// component of the triple, or "" if empty.
  StringRef getEnvironmentName() const;

  /// getOSAndEnvironmentName - Get the operating system and optional
  /// environment components as a single string (separated by a '-'
  /// if the environment component is present).
  StringRef getOSAndEnvironmentName() const;

  /// @}
  /// @name Convenience Predicates
  /// @{

  /// Test whether the architecture is 64-bit
  ///
  /// Note that this tests for 64-bit pointer width, and nothing else. Note
  /// that we intentionally expose only three predicates, 64-bit, 32-bit, and
  /// 16-bit. The inner details of pointer width for particular architectures
  /// is not summed up in the triple, and so only a coarse grained predicate
  /// system is provided.
  bool isArch64Bit() const;

  /// Test whether the architecture is 32-bit
  ///
  /// Note that this tests for 32-bit pointer width, and nothing else.
  bool isArch32Bit() const;

  /// Test whether the architecture is 16-bit
  ///
  /// Note that this tests for 16-bit pointer width, and nothing else.
  bool isArch16Bit() const;

  /// isOSVersionLT - Helper function for doing comparisons against version
  /// numbers included in the target triple.
  bool isOSVersionLT(unsigned Major, unsigned Minor = 0,
                     unsigned Micro = 0) const {
    unsigned LHS[3];
    getOSVersion(LHS[0], LHS[1], LHS[2]);

    if (LHS[0] != Major)
      return LHS[0] < Major;
    if (LHS[1] != Minor)
      return LHS[1] < Minor;
    if (LHS[2] != Micro)
      return LHS[2] < Micro;

    return false;
  }

  bool isOSVersionLT(const Triple &Other) const {
    unsigned RHS[3];
    Other.getOSVersion(RHS[0], RHS[1], RHS[2]);
    return isOSVersionLT(RHS[0], RHS[1], RHS[2]);
  }

  /// isMacOSXVersionLT - Comparison function for checking OS X version
  /// compatibility, which handles supporting skewed version numbering schemes
  /// used by the "darwin" triples.
  bool isMacOSXVersionLT(unsigned Major, unsigned Minor = 0,
                         unsigned Micro = 0) const {
    assert(isMacOSX() && "Not an OS X triple!");

    // If this is OS X, expect a sane version number.
    if (getOS() == Triple::MacOSX)
      return isOSVersionLT(Major, Minor, Micro);

    // Otherwise, compare to the "Darwin" number.
    assert(Major == 10 && "Unexpected major version");
    return isOSVersionLT(Minor + 4, Micro, 0);
  }

  /// isMacOSX - Is this a Mac OS X triple. For legacy reasons, we support both
  /// "darwin" and "osx" as OS X triples.
  bool isMacOSX() const {
    return getOS() == Triple::Darwin || getOS() == Triple::MacOSX;
  }

  /// Is this an iOS triple.
  /// Note: This identifies tvOS as a variant of iOS. If that ever
  /// changes, i.e., if the two operating systems diverge or their version
  /// numbers get out of sync, that will need to be changed.
  /// watchOS has completely different version numbers so it is not included.
  bool isiOS() const {
    return getOS() == Triple::IOS || isTvOS();
  }

  /// Is this an Apple tvOS triple.
  bool isTvOS() const {
    return getOS() == Triple::TvOS;
  }

  /// Is this an Apple watchOS triple.
  bool isWatchOS() const {
    return getOS() == Triple::WatchOS;
  }

  bool isWatchABI() const {
    return getSubArch() == Triple::ARMSubArch_v7k;
  }

  /// isOSDarwin - Is this a "Darwin" OS (OS X, iOS, or watchOS).
  bool isOSDarwin() const {
    return isMacOSX() || isiOS() || isWatchOS();
  }

  bool isSimulatorEnvironment() const {
    return getEnvironment() == Triple::Simulator;
  }

  bool isMacCatalystEnvironment() const {
    return getEnvironment() == Triple::MacABI;
  }

  bool isOSNetBSD() const {
    return getOS() == Triple::NetBSD;
  }

  bool isOSOpenBSD() const {
    return getOS() == Triple::OpenBSD;
  }

  bool isOSFreeBSD() const {
    return getOS() == Triple::FreeBSD;
  }

  bool isOSFuchsia() const {
    return getOS() == Triple::Fuchsia;
  }

  bool isOSDragonFly() const { return getOS() == Triple::DragonFly; }

  bool isOSSolaris() const {
    return getOS() == Triple::Solaris;
  }

  bool isOSIAMCU() const {
    return getOS() == Triple::ELFIAMCU;
  }

  bool isOSUnknown() const { return getOS() == Triple::UnknownOS; }

  bool isGNUEnvironment() const {
    EnvironmentType Env = getEnvironment();
    return Env == Triple::GNU || Env == Triple::GNUABIN32 ||
           Env == Triple::GNUABI64 || Env == Triple::GNUEABI ||
           Env == Triple::GNUEABIHF || Env == Triple::GNUX32;
  }

  bool isOSContiki() const {
    return getOS() == Triple::Contiki;
  }

  /// Tests whether the OS is Haiku.
  bool isOSHaiku() const {
    return getOS() == Triple::Haiku;
  }

  /// Tests whether the OS is Windows.
  bool isOSWindows() const {
    return getOS() == Triple::Win32;
  }

  /// Checks if the environment is MSVC.
  bool isKnownWindowsMSVCEnvironment() const {
    return isOSWindows() && getEnvironment() == Triple::MSVC;
  }

  /// Checks if the environment could be MSVC.
  bool isWindowsMSVCEnvironment() const {
    return isKnownWindowsMSVCEnvironment() ||
           (isOSWindows() && getEnvironment() == Triple::UnknownEnvironment);
  }

  bool isWindowsCoreCLREnvironment() const {
    return isOSWindows() && getEnvironment() == Triple::CoreCLR;
  }

  bool isWindowsItaniumEnvironment() const {
    return isOSWindows() && getEnvironment() == Triple::Itanium;
  }

  bool isWindowsCygwinEnvironment() const {
    return isOSWindows() && getEnvironment() == Triple::Cygnus;
  }

  bool isWindowsGNUEnvironment() const {
    return isOSWindows() && getEnvironment() == Triple::GNU;
  }

  /// Tests for either Cygwin or MinGW OS
  bool isOSCygMing() const {
    return isWindowsCygwinEnvironment() || isWindowsGNUEnvironment();
  }

  /// Is this a "Windows" OS targeting a "MSVCRT.dll" environment.
  bool isOSMSVCRT() const {
    return isWindowsMSVCEnvironment() || isWindowsGNUEnvironment() ||
           isWindowsItaniumEnvironment();
  }

  /// Tests whether the OS is NaCl (Native Client)
  bool isOSNaCl() const {
    return getOS() == Triple::NaCl;
  }

  /// Tests whether the OS is Linux.
  bool isOSLinux() const {
    return getOS() == Triple::Linux;
  }

  /// Tests whether the OS is kFreeBSD.
  bool isOSKFreeBSD() const {
    return getOS() == Triple::KFreeBSD;
  }

  /// Tests whether the OS is Hurd.
  bool isOSHurd() const {
    return getOS() == Triple::Hurd;
  }

  /// Tests whether the OS is WASI.
  bool isOSWASI() const {
    return getOS() == Triple::WASI;
  }

  /// Tests whether the OS is Emscripten.
  bool isOSEmscripten() const {
    return getOS() == Triple::Emscripten;
  }

  /// Tests whether the OS uses glibc.
  bool isOSGlibc() const {
    return (getOS() == Triple::Linux || getOS() == Triple::KFreeBSD ||
            getOS() == Triple::Hurd) &&
           !isAndroid();
  }

  /// Tests whether the OS is AIX.
  bool isOSAIX() const {
    return getOS() == Triple::AIX;
  }

  /// Tests whether the OS uses the ELF binary format.
  bool isOSBinFormatELF() const {
    return getObjectFormat() == Triple::ELF;
  }

  /// Tests whether the OS uses the COFF binary format.
  bool isOSBinFormatCOFF() const {
    return getObjectFormat() == Triple::COFF;
  }

  /// Tests whether the environment is MachO.
  bool isOSBinFormatMachO() const {
    return getObjectFormat() == Triple::MachO;
  }

  /// Tests whether the OS uses the Wasm binary format.
  bool isOSBinFormatWasm() const {
    return getObjectFormat() == Triple::Wasm;
  }

  /// Tests whether the OS uses the XCOFF binary format.
  bool isOSBinFormatXCOFF() const {
    return getObjectFormat() == Triple::XCOFF;
  }

  /// Tests whether the target is the PS4 CPU
  bool isPS4CPU() const {
    return getArch() == Triple::x86_64 &&
           getVendor() == Triple::SCEI &&
           getOS() == Triple::PS4;
  }

  /// Tests whether the target is the PS4 platform
  bool isPS4() const {
    return getVendor() == Triple::SCEI &&
           getOS() == Triple::PS4;
  }

  /// Tests whether the target is Android
  bool isAndroid() const { return getEnvironment() == Triple::Android; }

  bool isAndroidVersionLT(unsigned Major) const {
    assert(isAndroid() && "Not an Android triple!");

    unsigned Env[3];
    getEnvironmentVersion(Env[0], Env[1], Env[2]);

    // 64-bit targets did not exist before API level 21 (Lollipop).
    if (isArch64Bit() && Env[0] < 21)
      Env[0] = 21;

    return Env[0] < Major;
  }

  /// Tests whether the environment is musl-libc
  bool isMusl() const {
    return getEnvironment() == Triple::Musl ||
           getEnvironment() == Triple::MuslEABI ||
           getEnvironment() == Triple::MuslEABIHF;
  }

  /// Tests whether the target is SPIR (32- or 64-bit).
  bool isSPIR() const {
    return getArch() == Triple::spir || getArch() == Triple::spir64;
  }

  /// Tests whether the target is NVPTX (32- or 64-bit).
  bool isNVPTX() const {
    return getArch() == Triple::nvptx || getArch() == Triple::nvptx64;
  }

  /// Tests whether the target is Thumb (little and big endian).
  bool isThumb() const {
    return getArch() == Triple::thumb || getArch() == Triple::thumbeb;
  }

  /// Tests whether the target is ARM (little and big endian).
  bool isARM() const {
    return getArch() == Triple::arm || getArch() == Triple::armeb;
  }

  /// Tests whether the target is AArch64 (little and big endian).
  bool isAArch64() const {
    return getArch() == Triple::aarch64 || getArch() == Triple::aarch64_be;
  }

  /// Tests whether the target is MIPS 32-bit (little and big endian).
  bool isMIPS32() const {
    return getArch() == Triple::mips || getArch() == Triple::mipsel;
  }

  /// Tests whether the target is MIPS 64-bit (little and big endian).
  bool isMIPS64() const {
    return getArch() == Triple::mips64 || getArch() == Triple::mips64el;
  }

  /// Tests whether the target is MIPS (little and big endian, 32- or 64-bit).
  bool isMIPS() const {
    return isMIPS32() || isMIPS64();
  }

  /// Tests whether the target is 64-bit PowerPC (little and big endian).
  bool isPPC64() const {
    return getArch() == Triple::ppc64 || getArch() == Triple::ppc64le;
  }

  /// Tests whether the target is RISC-V (32- and 64-bit).
  bool isRISCV() const {
    return getArch() == Triple::riscv32 || getArch() == Triple::riscv64;
  }

  /// Tests whether the target supports comdat
  bool supportsCOMDAT() const {
    return !isOSBinFormatMachO();
  }

  /// Tests whether the target uses emulated TLS as default.
  bool hasDefaultEmulatedTLS() const {
    return isAndroid() || isOSOpenBSD() || isWindowsCygwinEnvironment();
  }

  /// @}
  /// @name Mutators
  /// @{

  /// setArch - Set the architecture (first) component of the triple
  /// to a known type.
  void setArch(ArchType Kind);

  /// setVendor - Set the vendor (second) component of the triple to a
  /// known type.
  void setVendor(VendorType Kind);

  /// setOS - Set the operating system (third) component of the triple
  /// to a known type.
  void setOS(OSType Kind);

  /// setEnvironment - Set the environment (fourth) component of the triple
  /// to a known type.
  void setEnvironment(EnvironmentType Kind);

  /// setObjectFormat - Set the object file format
  void setObjectFormat(ObjectFormatType Kind);

  /// setTriple - Set all components to the new triple \p Str.
  void setTriple(const Twine &Str);

  /// setArchName - Set the architecture (first) component of the
  /// triple by name.
  void setArchName(StringRef Str);

  /// setVendorName - Set the vendor (second) component of the triple
  /// by name.
  void setVendorName(StringRef Str);

  /// setOSName - Set the operating system (third) component of the
  /// triple by name.
  void setOSName(StringRef Str);

  /// setEnvironmentName - Set the optional environment (fourth)
  /// component of the triple by name.
  void setEnvironmentName(StringRef Str);

  /// setOSAndEnvironmentName - Set the operating system and optional
  /// environment components with a single string.
  void setOSAndEnvironmentName(StringRef Str);

  /// @}
  /// @name Helpers to build variants of a particular triple.
  /// @{

  /// Form a triple with a 32-bit variant of the current architecture.
  ///
  /// This can be used to move across "families" of architectures where useful.
  ///
  /// \returns A new triple with a 32-bit architecture or an unknown
  ///          architecture if no such variant can be found.
  llvm::Triple get32BitArchVariant() const;

  /// Form a triple with a 64-bit variant of the current architecture.
  ///
  /// This can be used to move across "families" of architectures where useful.
  ///
  /// \returns A new triple with a 64-bit architecture or an unknown
  ///          architecture if no such variant can be found.
  llvm::Triple get64BitArchVariant() const;

  /// Form a triple with a big endian variant of the current architecture.
  ///
  /// This can be used to move across "families" of architectures where useful.
  ///
  /// \returns A new triple with a big endian architecture or an unknown
  ///          architecture if no such variant can be found.
  llvm::Triple getBigEndianArchVariant() const;

  /// Form a triple with a little endian variant of the current architecture.
  ///
  /// This can be used to move across "families" of architectures where useful.
  ///
  /// \returns A new triple with a little endian architecture or an unknown
  ///          architecture if no such variant can be found.
  llvm::Triple getLittleEndianArchVariant() const;

  /// Get the (LLVM) name of the minimum ARM CPU for the arch we are targeting.
  ///
  /// \param Arch the architecture name (e.g., "armv7s"). If it is an empty
  /// string then the triple's arch name is used.
  StringRef getARMCPUForArch(StringRef Arch = StringRef()) const;

  /// Tests whether the target triple is little endian.
  ///
  /// \returns true if the triple is little endian, false otherwise.
  bool isLittleEndian() const;

  /// Test whether target triples are compatible.
  bool isCompatibleWith(const Triple &Other) const;

  /// Merge target triples.
  std::string merge(const Triple &Other) const;

  /// @}
  /// @name Static helpers for IDs.
  /// @{

  /// getArchTypeName - Get the canonical name for the \p Kind architecture.
  static StringRef getArchTypeName(ArchType Kind);

  /// getArchTypePrefix - Get the "prefix" canonical name for the \p Kind
  /// architecture. This is the prefix used by the architecture specific
  /// builtins, and is suitable for passing to \see
  /// Intrinsic::getIntrinsicForGCCBuiltin().
  ///
  /// \return - The architecture prefix, or 0 if none is defined.
  static StringRef getArchTypePrefix(ArchType Kind);

  /// getVendorTypeName - Get the canonical name for the \p Kind vendor.
  static StringRef getVendorTypeName(VendorType Kind);

  /// getOSTypeName - Get the canonical name for the \p Kind operating system.
  static StringRef getOSTypeName(OSType Kind);

  /// getEnvironmentTypeName - Get the canonical name for the \p Kind
  /// environment.
  static StringRef getEnvironmentTypeName(EnvironmentType Kind);

  /// @}
  /// @name Static helpers for converting alternate architecture names.
  /// @{

  /// getArchTypeForLLVMName - The canonical type for the given LLVM
  /// architecture name (e.g., "x86").
  static ArchType getArchTypeForLLVMName(StringRef Str);

  /// @}
};

} // End llvm namespace


#endif