include/llvm/CodeGen/TargetLoweringObjectFileImpl.h

   1 //==- llvm/CodeGen/TargetLoweringObjectFileImpl.h - Object Info --*- C++ -*-==//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements classes used to handle lowerings specific to common
  10 // object file formats.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H
  15 #define LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H
  16
  17 #include "llvm/IR/Module.h"
  18 #include "llvm/MC/MCExpr.h"
  19 #include "llvm/Target/TargetLoweringObjectFile.h"
  20
  21 namespace llvm {
  22
  23 class GlobalValue;
  24 class MachineModuleInfo;
  25 class Mangler;
  26 class MCContext;
  27 class MCSection;
  28 class MCSymbol;
  29 class TargetMachine;
  30
  31 class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
  32   bool UseInitArray = false;
  33   mutable unsigned NextUniqueID = 1;  // ID 0 is reserved for execute-only sections
  34
  35 protected:
  36   MCSymbolRefExpr::VariantKind PLTRelativeVariantKind =
  37       MCSymbolRefExpr::VK_None;
  38   const TargetMachine *TM;
  39
  40 public:
  41   TargetLoweringObjectFileELF() = default;
  42   ~TargetLoweringObjectFileELF() override = default;
  43
  44   void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
  45
  46   /// Emit Obj-C garbage collection and linker options.
  47   void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
  48
  49   void emitPersonalityValue(MCStreamer &Streamer, const DataLayout &DL,
  50                             const MCSymbol *Sym) const override;
  51
  52   /// Given a constant with the SectionKind, return a section that it should be
  53   /// placed in.
  54   MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
  55                                    const Constant *C,
  56                                    unsigned &Align) const override;
  57
  58   MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
  59                                       const TargetMachine &TM) const override;
  60
  61   MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
  62                                     const TargetMachine &TM) const override;
  63
  64   MCSection *getSectionForJumpTable(const Function &F,
  65                                     const TargetMachine &TM) const override;
  66
  67   bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
  68                                            const Function &F) const override;
  69
  70   /// Return an MCExpr to use for a reference to the specified type info global
  71   /// variable from exception handling information.
  72   const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,
  73                                         unsigned Encoding,
  74                                         const TargetMachine &TM,
  75                                         MachineModuleInfo *MMI,
  76                                         MCStreamer &Streamer) const override;
  77
  78   // The symbol that gets passed to .cfi_personality.
  79   MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
  80                                     const TargetMachine &TM,
  81                                     MachineModuleInfo *MMI) const override;
  82
  83   void InitializeELF(bool UseInitArray_);
  84   MCSection *getStaticCtorSection(unsigned Priority,
  85                                   const MCSymbol *KeySym) const override;
  86   MCSection *getStaticDtorSection(unsigned Priority,
  87                                   const MCSymbol *KeySym) const override;
  88
  89   const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
  90                                        const GlobalValue *RHS,
  91                                        const TargetMachine &TM) const override;
  92
  93   MCSection *getSectionForCommandLines() const override;
  94 };
  95
  96 class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
  97 public:
  98   TargetLoweringObjectFileMachO();
  99   ~TargetLoweringObjectFileMachO() override = default;
 100
 101   void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
 102
 103   /// Emit the module flags that specify the garbage collection information.
 104   void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
 105
 106   MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
 107                                     const TargetMachine &TM) const override;
 108
 109   MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
 110                                       const TargetMachine &TM) const override;
 111
 112   MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
 113                                    const Constant *C,
 114                                    unsigned &Align) const override;
 115
 116   /// The mach-o version of this method defaults to returning a stub reference.
 117   const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,
 118                                         unsigned Encoding,
 119                                         const TargetMachine &TM,
 120                                         MachineModuleInfo *MMI,
 121                                         MCStreamer &Streamer) const override;
 122
 123   // The symbol that gets passed to .cfi_personality.
 124   MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
 125                                     const TargetMachine &TM,
 126                                     MachineModuleInfo *MMI) const override;
 127
 128   /// Get MachO PC relative GOT entry relocation
 129   const MCExpr *getIndirectSymViaGOTPCRel(const MCSymbol *Sym,
 130                                           const MCValue &MV, int64_t Offset,
 131                                           MachineModuleInfo *MMI,
 132                                           MCStreamer &Streamer) const override;
 133
 134   void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,
 135                          const TargetMachine &TM) const override;
 136 };
 137
 138 class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {
 139   mutable unsigned NextUniqueID = 0;
 140
 141 public:
 142   ~TargetLoweringObjectFileCOFF() override = default;
 143
 144   void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
 145   MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
 146                                       const TargetMachine &TM) const override;
 147
 148   MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
 149                                     const TargetMachine &TM) const override;
 150
 151   void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,
 152                          const TargetMachine &TM) const override;
 153
 154   MCSection *getSectionForJumpTable(const Function &F,
 155                                     const TargetMachine &TM) const override;
 156
 157   /// Emit Obj-C garbage collection and linker options.
 158   void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
 159
 160   MCSection *getStaticCtorSection(unsigned Priority,
 161                                   const MCSymbol *KeySym) const override;
 162   MCSection *getStaticDtorSection(unsigned Priority,
 163                                   const MCSymbol *KeySym) const override;
 164
 165   void emitLinkerFlagsForGlobal(raw_ostream &OS,
 166                                 const GlobalValue *GV) const override;
 167
 168   void emitLinkerFlagsForUsed(raw_ostream &OS,
 169                               const GlobalValue *GV) const override;
 170
 171   const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
 172                                        const GlobalValue *RHS,
 173                                        const TargetMachine &TM) const override;
 174
 175   /// Given a mergeable constant with the specified size and relocation
 176   /// information, return a section that it should be placed in.
 177   MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
 178                                    const Constant *C,
 179                                    unsigned &Align) const override;
 180 };
 181
 182 class TargetLoweringObjectFileWasm : public TargetLoweringObjectFile {
 183   mutable unsigned NextUniqueID = 0;
 184
 185 public:
 186   TargetLoweringObjectFileWasm() = default;
 187   ~TargetLoweringObjectFileWasm() override = default;
 188
 189   MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
 190                                       const TargetMachine &TM) const override;
 191
 192   MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
 193                                     const TargetMachine &TM) const override;
 194
 195   bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
 196                                            const Function &F) const override;
 197
 198   void InitializeWasm();
 199   MCSection *getStaticCtorSection(unsigned Priority,
 200                                   const MCSymbol *KeySym) const override;
 201   MCSection *getStaticDtorSection(unsigned Priority,
 202                                   const MCSymbol *KeySym) const override;
 203
 204   const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
 205                                        const GlobalValue *RHS,
 206                                        const TargetMachine &TM) const override;
 207 };
 208
 209 } // end namespace llvm
 210
 211 #endif // LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H