//==- 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