Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//==- llvm/CodeGen/TargetLoweringObjectFileImpl.h - Object Info --*- 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

//

//===----------------------------------------------------------------------===//

//

// This file implements classes used to handle lowerings specific to common

// object file formats.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H

#define LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H

#include "llvm/ADT/SmallPtrSet.h"

#include "llvm/BinaryFormat/XCOFF.h"

#include "llvm/MC/MCExpr.h"

#include "llvm/Target/TargetLoweringObjectFile.h"

namespace llvm {

class GlobalValue;

class MachineModuleInfo;

class MachineFunction;

class MCContext;

class MCExpr;

class MCSection;

class MCSymbol;

class Module;

class TargetMachine;

class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {

  bool UseInitArray = false;

  mutable unsigned NextUniqueID = 1;  // ID 0 is reserved for execute-only sections

  SmallPtrSet<GlobalObject *, 2> Used;

protected:

  MCSymbolRefExpr::VariantKind PLTRelativeVariantKind =

      MCSymbolRefExpr::VK_None;

public:

  TargetLoweringObjectFileELF();

  ~TargetLoweringObjectFileELF() override = default;

  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;

  void getModuleMetadata(Module &M) override;

  /// Emit Obj-C garbage collection and linker options.

  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;

  void emitPersonalityValue(MCStreamer &Streamer, const DataLayout &DL,

                            const MCSymbol *Sym) const override;

  /// Given a constant with the SectionKind, return a section that it should be

  /// placed in.

  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,

                                   const Constant *C,

                                   Align &Alignment) const override;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  MCSection *getSectionForJumpTable(const Function &F,

                                    const TargetMachine &TM) const override;

  MCSection *getSectionForLSDA(const Function &F, const MCSymbol &FnSym,

                               const TargetMachine &TM) const override;

  MCSection *

  getSectionForMachineBasicBlock(const Function &F,

                                 const MachineBasicBlock &MBB,

                                 const TargetMachine &TM) const override;

  MCSection *

  getUniqueSectionForFunction(const Function &F,

                              const TargetMachine &TM) const override;

  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,

                                           const Function &F) const override;

  /// Return an MCExpr to use for a reference to the specified type info global

  /// variable from exception handling information.

  const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,

                                        unsigned Encoding,

                                        const TargetMachine &TM,

                                        MachineModuleInfo *MMI,

                                        MCStreamer &Streamer) const override;

  // The symbol that gets passed to .cfi_personality.

  MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,

                                    const TargetMachine &TM,

                                    MachineModuleInfo *MMI) const override;

  void InitializeELF(bool UseInitArray_);

  MCSection *getStaticCtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  MCSection *getStaticDtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,

                                       const GlobalValue *RHS,

                                       const TargetMachine &TM) const override;

  const MCExpr *lowerDSOLocalEquivalent(const DSOLocalEquivalent *Equiv,

                                        const TargetMachine &TM) const override;

  MCSection *getSectionForCommandLines() const override;

};

class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {

public:

  TargetLoweringObjectFileMachO();

  ~TargetLoweringObjectFileMachO() override = default;

  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;

  MCSection *getStaticDtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  /// Emit the module flags that specify the garbage collection information.

  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,

                                   const Constant *C,

                                   Align &Alignment) const override;

  /// The mach-o version of this method defaults to returning a stub reference.

  const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,

                                        unsigned Encoding,

                                        const TargetMachine &TM,

                                        MachineModuleInfo *MMI,

                                        MCStreamer &Streamer) const override;

  // The symbol that gets passed to .cfi_personality.

  MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,

                                    const TargetMachine &TM,

                                    MachineModuleInfo *MMI) const override;

  /// Get MachO PC relative GOT entry relocation

  const MCExpr *getIndirectSymViaGOTPCRel(const GlobalValue *GV,

                                          const MCSymbol *Sym,

                                          const MCValue &MV, int64_t Offset,

                                          MachineModuleInfo *MMI,

                                          MCStreamer &Streamer) const override;

  void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,

                         const TargetMachine &TM) const override;

};

class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {

  mutable unsigned NextUniqueID = 0;

  const TargetMachine *TM = nullptr;

public:

  ~TargetLoweringObjectFileCOFF() override = default;

  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,

                         const TargetMachine &TM) const override;

  MCSection *getSectionForJumpTable(const Function &F,

                                    const TargetMachine &TM) const override;

  /// Emit Obj-C garbage collection and linker options.

  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;

  MCSection *getStaticCtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  MCSection *getStaticDtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,

                                       const GlobalValue *RHS,

                                       const TargetMachine &TM) const override;

  /// Given a mergeable constant with the specified size and relocation

  /// information, return a section that it should be placed in.

  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,

                                   const Constant *C,

                                   Align &Alignment) const override;

private:

  void emitLinkerDirectives(MCStreamer &Streamer, Module &M) const;

};

class TargetLoweringObjectFileWasm : public TargetLoweringObjectFile {

  mutable unsigned NextUniqueID = 0;

public:

  TargetLoweringObjectFileWasm() = default;

  ~TargetLoweringObjectFileWasm() override = default;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,

                                           const Function &F) const override;

  void InitializeWasm();

  MCSection *getStaticCtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  MCSection *getStaticDtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,

                                       const GlobalValue *RHS,

                                       const TargetMachine &TM) const override;

};

class TargetLoweringObjectFileXCOFF : public TargetLoweringObjectFile {

public:

  TargetLoweringObjectFileXCOFF() = default;

  ~TargetLoweringObjectFileXCOFF() override = default;

  static bool ShouldEmitEHBlock(const MachineFunction *MF);

  static bool ShouldSetSSPCanaryBitInTB(const MachineFunction *MF);

  static MCSymbol *getEHInfoTableSymbol(const MachineFunction *MF);

  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;

  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,

                                           const Function &F) const override;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

  MCSection *getStaticCtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  MCSection *getStaticDtorSection(unsigned Priority,

                                  const MCSymbol *KeySym) const override;

  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,

                                       const GlobalValue *RHS,

                                       const TargetMachine &TM) const override;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  MCSection *getSectionForJumpTable(const Function &F,

                                    const TargetMachine &TM) const override;

  /// Given a constant with the SectionKind, return a section that it should be

  /// placed in.

  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,

                                   const Constant *C,

                                   Align &Alignment) const override;

  static XCOFF::StorageClass getStorageClassForGlobal(const GlobalValue *GV);

  MCSection *

  getSectionForFunctionDescriptor(const Function *F,

                                  const TargetMachine &TM) const override;

  MCSection *getSectionForTOCEntry(const MCSymbol *Sym,

                                   const TargetMachine &TM) const override;

  /// For external functions, this will always return a function descriptor

  /// csect.

  MCSection *

  getSectionForExternalReference(const GlobalObject *GO,

                                 const TargetMachine &TM) const override;

  /// For functions, this will always return a function descriptor symbol.

  MCSymbol *getTargetSymbol(const GlobalValue *GV,

                            const TargetMachine &TM) const override;

  MCSymbol *getFunctionEntryPointSymbol(const GlobalValue *Func,

                                        const TargetMachine &TM) const override;

  /// For functions, this will return the LSDA section. If option

  /// -ffunction-sections is on, this will return a unique csect with the

  /// function name appended to .gcc_except_table as a suffix of the LSDA

  /// section name.

  MCSection *getSectionForLSDA(const Function &F, const MCSymbol &FnSym,

                               const TargetMachine &TM) const override;

};

class TargetLoweringObjectFileGOFF : public TargetLoweringObjectFile {

public:

  TargetLoweringObjectFileGOFF();

  ~TargetLoweringObjectFileGOFF() override = default;

  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,

                                    const TargetMachine &TM) const override;

  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,

                                      const TargetMachine &TM) const override;

};

} // end namespace llvm

#endif // LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H