text: //===- ToolChain.h - Collections of tools for one platform ------*- 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_CLANG_DRIVER_TOOLCHAIN_H
  #define LLVM_CLANG_DRIVER_TOOLCHAIN_H
  
  #include "clang/Basic/DebugInfoOptions.h"
  #include "clang/Basic/LLVM.h"
  #include "clang/Basic/LangOptions.h"
  #include "clang/Basic/Sanitizers.h"
  #include "clang/Driver/Action.h"
  #include "clang/Driver/Multilib.h"
  #include "clang/Driver/Types.h"
  #include "llvm/ADT/ArrayRef.h"
  #include "llvm/ADT/SmallVector.h"
  #include "llvm/ADT/StringRef.h"
  #include "llvm/ADT/Triple.h"
  #include "llvm/MC/MCTargetOptions.h"
  #include "llvm/Option/Option.h"
  #include "llvm/Support/VersionTuple.h"
  #include "llvm/Target/TargetOptions.h"
  #include <cassert>
  #include <memory>
  #include <string>
  #include <utility>
  
  namespace llvm {
  namespace opt {
  
  class Arg;
  class ArgList;
  class DerivedArgList;
  
  } // namespace opt
  namespace vfs {
  
  class FileSystem;
  
  } // namespace vfs
  } // namespace llvm
  
  namespace clang {
  
  class ObjCRuntime;
  
  namespace driver {
    class HCCInstallationDetector;
    class Driver;
    class InputInfo;
    class SanitizerArgs;
    class Tool;
    class XRayArgs;
  
  /// Helper structure used to pass information extracted from clang executable
  /// name such as `i686-linux-android-g++`.
  struct ParsedClangName {
    /// Target part of the executable name, as `i686-linux-android`.
    std::string TargetPrefix;
  
    /// Driver mode part of the executable name, as `g++`.
    std::string ModeSuffix;
  
    /// Corresponding driver mode argument, as '--driver-mode=g++'
    const char *DriverMode = nullptr;
  
    /// True if TargetPrefix is recognized as a registered target name.
    bool TargetIsValid = false;
  
    ParsedClangName() = default;
    ParsedClangName(std::string Suffix, const char *Mode)
        : ModeSuffix(Suffix), DriverMode(Mode) {}
    ParsedClangName(std::string Target, std::string Suffix, const char *Mode,
                    bool IsRegistered)
        : TargetPrefix(Target), ModeSuffix(Suffix), DriverMode(Mode),
          TargetIsValid(IsRegistered) {}
  
    bool isEmpty() const {
      return TargetPrefix.empty() && ModeSuffix.empty() && DriverMode == nullptr;
    }
  };
  
  /// ToolChain - Access to tools for a single platform.
  class ToolChain {
  public:
    using path_list = SmallVector<std::string, 16>;
  
    enum CXXStdlibType {
      CST_Libcxx,
      CST_Libstdcxx
    };
  
    enum RuntimeLibType {
      RLT_CompilerRT,
      RLT_Libgcc
    };
  
    enum UnwindLibType {
      UNW_None,
      UNW_CompilerRT,
      UNW_Libgcc
    };
  
    enum RTTIMode {
      RM_Enabled,
      RM_Disabled,
    };
  
    enum FileType { FT_Object, FT_Static, FT_Shared };
  
  private:
    friend class RegisterEffectiveTriple;
  
    const Driver &D;
    llvm::Triple Triple;
    const llvm::opt::ArgList &Args;
  
    // We need to initialize CachedRTTIArg before CachedRTTIMode
    const llvm::opt::Arg *const CachedRTTIArg;
  
    const RTTIMode CachedRTTIMode;
  
    /// The list of toolchain specific path prefixes to search for libraries.
    path_list LibraryPaths;
  
    /// The list of toolchain specific path prefixes to search for files.
    path_list FilePaths;
  
    /// The list of toolchain specific path prefixes to search for programs.
    path_list ProgramPaths;
  
    mutable std::unique_ptr<Tool> Clang;
    mutable std::unique_ptr<Tool> Assemble;
    mutable std::unique_ptr<Tool> Link;
    mutable std::unique_ptr<Tool> OffloadBundler;
  
    Tool *getClang() const;
    Tool *getAssemble() const;
    Tool *getLink() const;
    Tool *getClangAs() const;
    Tool *getOffloadBundler() const;
  
    mutable std::unique_ptr<SanitizerArgs> SanitizerArguments;
    mutable std::unique_ptr<XRayArgs> XRayArguments;
  
    /// The effective clang triple for the current Job.
    mutable llvm::Triple EffectiveTriple;
  
    /// Set the toolchain's effective clang triple.
    void setEffectiveTriple(llvm::Triple ET) const {
      EffectiveTriple = std::move(ET);
    }
  
  protected:
    MultilibSet Multilibs;
    Multilib SelectedMultilib;
  
    ToolChain(const Driver &D, const llvm::Triple &T,
              const llvm::opt::ArgList &Args);
  
    void setTripleEnvironment(llvm::Triple::EnvironmentType Env);
  
    virtual Tool *buildAssembler() const;
    virtual Tool *buildLinker() const;
    virtual Tool *getTool(Action::ActionClass AC) const;
  
    /// \name Utilities for implementing subclasses.
    ///@{
    static void addSystemInclude(const llvm::opt::ArgList &DriverArgs,
                                 llvm::opt::ArgStringList &CC1Args,
                                 const Twine &Path);
    static void addExternCSystemInclude(const llvm::opt::ArgList &DriverArgs,
                                        llvm::opt::ArgStringList &CC1Args,
                                        const Twine &Path);
    static void
        addExternCSystemIncludeIfExists(const llvm::opt::ArgList &DriverArgs,
                                        llvm::opt::ArgStringList &CC1Args,
                                        const Twine &Path);
    static void addSystemIncludes(const llvm::opt::ArgList &DriverArgs,
                                  llvm::opt::ArgStringList &CC1Args,
                                  ArrayRef<StringRef> Paths);
    ///@}
  
  public:
    virtual ~ToolChain();
  
    // Accessors
  
    const Driver &getDriver() const { return D; }
    llvm::vfs::FileSystem &getVFS() const;
    const llvm::Triple &getTriple() const { return Triple; }
  
    /// Get the toolchain's aux triple, if it has one.
    ///
    /// Exactly what the aux triple represents depends on the toolchain, but for
    /// example when compiling CUDA code for the GPU, the triple might be NVPTX,
    /// while the aux triple is the host (CPU) toolchain, e.g. x86-linux-gnu.
    virtual const llvm::Triple *getAuxTriple() const { return nullptr; }
  
    /// Some toolchains need to modify the file name, for example to replace the
    /// extension for object files with .cubin for OpenMP offloading to Nvidia
    /// GPUs.
    virtual std::string getInputFilename(const InputInfo &Input) const;
  
    llvm::Triple::ArchType getArch() const { return Triple.getArch(); }
    StringRef getArchName() const { return Triple.getArchName(); }
    StringRef getPlatform() const { return Triple.getVendorName(); }
    StringRef getOS() const { return Triple.getOSName(); }
  
    /// Provide the default architecture name (as expected by -arch) for
    /// this toolchain.
    StringRef getDefaultUniversalArchName() const;
  
    std::string getTripleString() const {
      return Triple.getTriple();
    }
  
    /// Get the toolchain's effective clang triple.
    const llvm::Triple &getEffectiveTriple() const {
      assert(!EffectiveTriple.getTriple().empty() && "No effective triple");
      return EffectiveTriple;
    }
  
    path_list &getLibraryPaths() { return LibraryPaths; }
    const path_list &getLibraryPaths() const { return LibraryPaths; }
  
    path_list &getFilePaths() { return FilePaths; }
    const path_list &getFilePaths() const { return FilePaths; }
  
    path_list &getProgramPaths() { return ProgramPaths; }
    const path_list &getProgramPaths() const { return ProgramPaths; }
  
    const MultilibSet &getMultilibs() const { return Multilibs; }
  
    const Multilib &getMultilib() const { return SelectedMultilib; }
  
    const SanitizerArgs& getSanitizerArgs() const;
  
    const XRayArgs& getXRayArgs() const;
  
    // Returns the Arg * that explicitly turned on/off rtti, or nullptr.
    const llvm::opt::Arg *getRTTIArg() const { return CachedRTTIArg; }
  
    // Returns the RTTIMode for the toolchain with the current arguments.
    RTTIMode getRTTIMode() const { return CachedRTTIMode; }
  
    /// Return any implicit target and/or mode flag for an invocation of
    /// the compiler driver as `ProgName`.
    ///
    /// For example, when called with i686-linux-android-g++, the first element
    /// of the return value will be set to `"i686-linux-android"` and the second
    /// will be set to "--driver-mode=g++"`.
    /// It is OK if the target name is not registered. In this case the return
    /// value contains false in the field TargetIsValid.
    ///
    /// \pre `llvm::InitializeAllTargets()` has been called.
    /// \param ProgName The name the Clang driver was invoked with (from,
    /// e.g., argv[0]).
    /// \return A structure of type ParsedClangName that contains the executable
    /// name parts.
    static ParsedClangName getTargetAndModeFromProgramName(StringRef ProgName);
  
    // Tool access.
  
    /// TranslateArgs - Create a new derived argument list for any argument
    /// translations this ToolChain may wish to perform, or 0 if no tool chain
    /// specific translations are needed. If \p DeviceOffloadKind is specified
    /// the translation specific for that offload kind is performed.
    ///
    /// \param BoundArch - The bound architecture name, or 0.
    /// \param DeviceOffloadKind - The device offload kind used for the
    /// translation.
    virtual llvm::opt::DerivedArgList *
    TranslateArgs(const llvm::opt::DerivedArgList &Args, StringRef BoundArch,
                  Action::OffloadKind DeviceOffloadKind) const {
      return nullptr;
    }
  
    /// TranslateOpenMPTargetArgs - Create a new derived argument list for
    /// that contains the OpenMP target specific flags passed via
    /// -Xopenmp-target -opt=val OR -Xopenmp-target=<triple> -opt=val
    virtual llvm::opt::DerivedArgList *TranslateOpenMPTargetArgs(
        const llvm::opt::DerivedArgList &Args, bool SameTripleAsHost,
        SmallVectorImpl<llvm::opt::Arg *> &AllocatedArgs) const;
  
    /// Choose a tool to use to handle the action \p JA.
    ///
    /// This can be overridden when a particular ToolChain needs to use
    /// a compiler other than Clang.
    virtual Tool *SelectTool(const JobAction &JA) const;
  
    // Helper methods
  
    std::string GetFilePath(const char *Name) const;
    std::string GetProgramPath(const char *Name) const;
  
    /// Returns the linker path, respecting the -fuse-ld= argument to determine
    /// the linker suffix or name.
    std::string GetLinkerPath() const;
  
    /// Dispatch to the specific toolchain for verbose printing.
    ///
    /// This is used when handling the verbose option to print detailed,
    /// toolchain-specific information useful for understanding the behavior of
    /// the driver on a specific platform.
    virtual void printVerboseInfo(raw_ostream &OS) const {}
  
    // Platform defaults information
  
    /// Returns true if the toolchain is targeting a non-native
    /// architecture.
    virtual bool isCrossCompiling() const;
  
    /// HasNativeLTOLinker - Check whether the linker and related tools have
    /// native LLVM support.
    virtual bool HasNativeLLVMSupport() const;
  
    /// LookupTypeForExtension - Return the default language type to use for the
    /// given extension.
    virtual types::ID LookupTypeForExtension(StringRef Ext) const;
  
    /// IsBlocksDefault - Does this tool chain enable -fblocks by default.
    virtual bool IsBlocksDefault() const { return false; }
  
    /// IsIntegratedAssemblerDefault - Does this tool chain enable -integrated-as
    /// by default.
    virtual bool IsIntegratedAssemblerDefault() const { return false; }
  
    /// Check if the toolchain should use the integrated assembler.
    virtual bool useIntegratedAs() const;
  
    /// IsMathErrnoDefault - Does this tool chain use -fmath-errno by default.
    virtual bool IsMathErrnoDefault() const { return true; }
  
    /// IsEncodeExtendedBlockSignatureDefault - Does this tool chain enable
    /// -fencode-extended-block-signature by default.
    virtual bool IsEncodeExtendedBlockSignatureDefault() const { return false; }
  
    /// IsObjCNonFragileABIDefault - Does this tool chain set
    /// -fobjc-nonfragile-abi by default.
    virtual bool IsObjCNonFragileABIDefault() const { return false; }
  
    /// UseObjCMixedDispatchDefault - When using non-legacy dispatch, should the
    /// mixed dispatch method be used?
    virtual bool UseObjCMixedDispatch() const { return false; }
  
    /// Check whether to enable x86 relax relocations by default.
    virtual bool useRelaxRelocations() const;
  
    /// GetDefaultStackProtectorLevel - Get the default stack protector level for
    /// this tool chain (0=off, 1=on, 2=strong, 3=all).
    virtual unsigned GetDefaultStackProtectorLevel(bool KernelOrKext) const {
      return 0;
    }
  
    /// Get the default trivial automatic variable initialization.
    virtual LangOptions::TrivialAutoVarInitKind
    GetDefaultTrivialAutoVarInit() const {
      return LangOptions::TrivialAutoVarInitKind::Uninitialized;
    }
  
    /// GetDefaultLinker - Get the default linker to use.
    virtual const char *getDefaultLinker() const { return "ld"; }
  
    /// GetDefaultRuntimeLibType - Get the default runtime library variant to use.
    virtual RuntimeLibType GetDefaultRuntimeLibType() const {
      return ToolChain::RLT_Libgcc;
    }
  
    virtual CXXStdlibType GetDefaultCXXStdlibType() const {
      return ToolChain::CST_Libstdcxx;
    }
  
    virtual UnwindLibType GetDefaultUnwindLibType() const {
      return ToolChain::UNW_None;
    }
  
    virtual std::string getCompilerRTPath() const;
  
    virtual std::string getCompilerRT(const llvm::opt::ArgList &Args,
                                      StringRef Component,
                                      FileType Type = ToolChain::FT_Static) const;
  
    const char *
    getCompilerRTArgString(const llvm::opt::ArgList &Args, StringRef Component,
                           FileType Type = ToolChain::FT_Static) const;
  
    // Returns target specific runtime path if it exists.
    virtual Optional<std::string> getRuntimePath() const;
  
    // Returns target specific C++ library path if it exists.
    virtual Optional<std::string> getCXXStdlibPath() const;
  
    // Returns <ResourceDir>/lib/<OSName>/<arch>.  This is used by runtimes (such
    // as OpenMP) to find arch-specific libraries.
    std::string getArchSpecificLibPath() const;
  
    // Returns <OSname> part of above.
    StringRef getOSLibName() const;
  
    /// needsProfileRT - returns true if instrumentation profile is on.
    static bool needsProfileRT(const llvm::opt::ArgList &Args);
  
    /// Returns true if gcov instrumentation (-fprofile-arcs or --coverage) is on.
    static bool needsGCovInstrumentation(const llvm::opt::ArgList &Args);
  
    /// IsUnwindTablesDefault - Does this tool chain use -funwind-tables
    /// by default.
    virtual bool IsUnwindTablesDefault(const llvm::opt::ArgList &Args) const;
  
    /// Test whether this toolchain defaults to PIC.
    virtual bool isPICDefault() const = 0;
  
    /// Test whether this toolchain defaults to PIE.
    virtual bool isPIEDefault() const = 0;
  
    /// Test whether this toolchaind defaults to non-executable stacks.
    virtual bool isNoExecStackDefault() const;
  
    /// Tests whether this toolchain forces its default for PIC, PIE or
    /// non-PIC.  If this returns true, any PIC related flags should be ignored
    /// and instead the results of \c isPICDefault() and \c isPIEDefault() are
    /// used exclusively.
    virtual bool isPICDefaultForced() const = 0;
  
    /// SupportsProfiling - Does this tool chain support -pg.
    virtual bool SupportsProfiling() const { return true; }
  
    /// Complain if this tool chain doesn't support Objective-C ARC.
    virtual void CheckObjCARC() const {}
  
    /// Get the default debug info format. Typically, this is DWARF.
    virtual codegenoptions::DebugInfoFormat getDefaultDebugFormat() const {
      return codegenoptions::DIF_DWARF;
    }
  
    /// UseDwarfDebugFlags - Embed the compile options to clang into the Dwarf
    /// compile unit information.
    virtual bool UseDwarfDebugFlags() const { return false; }
  
    // Return the DWARF version to emit, in the absence of arguments
    // to the contrary.
    virtual unsigned GetDefaultDwarfVersion() const { return 4; }
  
    // True if the driver should assume "-fstandalone-debug"
    // in the absence of an option specifying otherwise,
    // provided that debugging was requested in the first place.
    // i.e. a value of 'true' does not imply that debugging is wanted.
    virtual bool GetDefaultStandaloneDebug() const { return false; }
  
    // Return the default debugger "tuning."
    virtual llvm::DebuggerKind getDefaultDebuggerTuning() const {
      return llvm::DebuggerKind::GDB;
    }
  
    /// Does this toolchain supports given debug info option or not.
    virtual bool supportsDebugInfoOption(const llvm::opt::Arg *) const {
      return true;
    }
  
    /// Adjust debug information kind considering all passed options.
    virtual void adjustDebugInfoKind(codegenoptions::DebugInfoKind &DebugInfoKind,
                                     const llvm::opt::ArgList &Args) const {}
  
    /// GetExceptionModel - Return the tool chain exception model.
    virtual llvm::ExceptionHandling
    GetExceptionModel(const llvm::opt::ArgList &Args) const;
  
    /// SupportsEmbeddedBitcode - Does this tool chain support embedded bitcode.
    virtual bool SupportsEmbeddedBitcode() const { return false; }
  
    /// getThreadModel() - Which thread model does this target use?
    virtual std::string getThreadModel() const { return "posix"; }
  
    /// isThreadModelSupported() - Does this target support a thread model?
    virtual bool isThreadModelSupported(const StringRef Model) const;
  
    /// ComputeLLVMTriple - Return the LLVM target triple to use, after taking
    /// command line arguments into account.
    virtual std::string
    ComputeLLVMTriple(const llvm::opt::ArgList &Args,
                      types::ID InputType = types::TY_INVALID) const;
  
    /// ComputeEffectiveClangTriple - Return the Clang triple to use for this
    /// target, which may take into account the command line arguments. For
    /// example, on Darwin the -mmacosx-version-min= command line argument (which
    /// sets the deployment target) determines the version in the triple passed to
    /// Clang.
    virtual std::string ComputeEffectiveClangTriple(
        const llvm::opt::ArgList &Args,
        types::ID InputType = types::TY_INVALID) const;
  
    /// getDefaultObjCRuntime - Return the default Objective-C runtime
    /// for this platform.
    ///
    /// FIXME: this really belongs on some sort of DeploymentTarget abstraction
    virtual ObjCRuntime getDefaultObjCRuntime(bool isNonFragile) const;
  
    /// hasBlocksRuntime - Given that the user is compiling with
    /// -fblocks, does this tool chain guarantee the existence of a
    /// blocks runtime?
    ///
    /// FIXME: this really belongs on some sort of DeploymentTarget abstraction
    virtual bool hasBlocksRuntime() const { return true; }
  
    /// Add the clang cc1 arguments for system include paths.
    ///
    /// This routine is responsible for adding the necessary cc1 arguments to
    /// include headers from standard system header directories.
    virtual void
    AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                              llvm::opt::ArgStringList &CC1Args) const;
  
    /// Add options that need to be passed to cc1 for this target.
    virtual void addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
                                       llvm::opt::ArgStringList &CC1Args,
                                       Action::OffloadKind DeviceOffloadKind) const;
  
    /// Add warning options that need to be passed to cc1 for this target.
    virtual void addClangWarningOptions(llvm::opt::ArgStringList &CC1Args) const;
  
    // GetRuntimeLibType - Determine the runtime library type to use with the
    // given compilation arguments.
    virtual RuntimeLibType
    GetRuntimeLibType(const llvm::opt::ArgList &Args) const;
  
    // GetCXXStdlibType - Determine the C++ standard library type to use with the
    // given compilation arguments.
    virtual CXXStdlibType GetCXXStdlibType(const llvm::opt::ArgList &Args) const;
  
    // GetUnwindLibType - Determine the unwind library type to use with the
    // given compilation arguments.
    virtual UnwindLibType GetUnwindLibType(const llvm::opt::ArgList &Args) const;
  
    /// AddClangCXXStdlibIncludeArgs - Add the clang -cc1 level arguments to set
    /// the include paths to use for the given C++ standard library type.
    virtual void
    AddClangCXXStdlibIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                                 llvm::opt::ArgStringList &CC1Args) const;
  
    /// Returns if the C++ standard library should be linked in.
    /// Note that e.g. -lm should still be linked even if this returns false.
    bool ShouldLinkCXXStdlib(const llvm::opt::ArgList &Args) const;
  
    /// AddCXXStdlibLibArgs - Add the system specific linker arguments to use
    /// for the given C++ standard library type.
    virtual void AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args,
                                     llvm::opt::ArgStringList &CmdArgs) const;
  
    /// AddFilePathLibArgs - Add each thing in getFilePaths() as a "-L" option.
    void AddFilePathLibArgs(const llvm::opt::ArgList &Args,
                            llvm::opt::ArgStringList &CmdArgs) const;
  
    /// AddCCKextLibArgs - Add the system specific linker arguments to use
    /// for kernel extensions (Darwin-specific).
    virtual void AddCCKextLibArgs(const llvm::opt::ArgList &Args,
                                  llvm::opt::ArgStringList &CmdArgs) const;
  
    /// AddFastMathRuntimeIfAvailable - If a runtime library exists that sets
    /// global flags for unsafe floating point math, add it and return true.
    ///
    /// This checks for presence of the -Ofast, -ffast-math or -funsafe-math flags.
    virtual bool AddFastMathRuntimeIfAvailable(
        const llvm::opt::ArgList &Args, llvm::opt::ArgStringList &CmdArgs) const;
  
    /// addProfileRTLibs - When -fprofile-instr-profile is specified, try to pass
    /// a suitable profile runtime library to the linker.
    virtual void addProfileRTLibs(const llvm::opt::ArgList &Args,
                                  llvm::opt::ArgStringList &CmdArgs) const;
  
    /// Add arguments to use system-specific CUDA includes.
    virtual void AddCudaIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                                    llvm::opt::ArgStringList &CC1Args) const;
  
    virtual void AddHCCIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                                   llvm::opt::ArgStringList &CC1Args) const;
  
    /// Add arguments to use MCU GCC toolchain includes.
    virtual void AddIAMCUIncludeArgs(const llvm::opt::ArgList &DriverArgs,
                                     llvm::opt::ArgStringList &CC1Args) const;
  
    /// On Windows, returns the MSVC compatibility version.
    virtual VersionTuple computeMSVCVersion(const Driver *D,
                                            const llvm::opt::ArgList &Args) const;
  
    /// Return sanitizers which are available in this toolchain.
    virtual SanitizerMask getSupportedSanitizers() const;
  
    /// Return sanitizers which are enabled by default.
    virtual SanitizerMask getDefaultSanitizers() const {
      return SanitizerMask();
    }
  };
  
  /// Set a ToolChain's effective triple. Reset it when the registration object
  /// is destroyed.
  class RegisterEffectiveTriple {
    const ToolChain &TC;
  
  public:
    RegisterEffectiveTriple(const ToolChain &TC, llvm::Triple T) : TC(TC) {
      TC.setEffectiveTriple(std::move(T));
    }
  
    ~RegisterEffectiveTriple() { TC.setEffectiveTriple(llvm::Triple()); }
  };
  
  } // namespace driver
  
  } // namespace clang
  
  #endif // LLVM_CLANG_DRIVER_TOOLCHAIN_H
  