TargetLoweringObjectFileImpl.h revision 360784 
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/BinaryFormat/XCOFF.h"
18#include "llvm/IR/Module.h"
19#include "llvm/MC/MCExpr.h"
20#include "llvm/Target/TargetLoweringObjectFile.h"
21
22namespace llvm {
23
24class GlobalValue;
25class MachineModuleInfo;
26class Mangler;
27class MCContext;
28class MCSection;
29class MCSymbol;
30class TargetMachine;
31
32class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
33  bool UseInitArray = false;
34  mutable unsigned NextUniqueID = 1;  // ID 0 is reserved for execute-only sections
35
36protected:
37  MCSymbolRefExpr::VariantKind PLTRelativeVariantKind =
38      MCSymbolRefExpr::VK_None;
39  const TargetMachine *TM = nullptr;
40
41public:
42  TargetLoweringObjectFileELF() = default;
43  ~TargetLoweringObjectFileELF() override = default;
44
45  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
46
47  /// Emit Obj-C garbage collection and linker options.
48  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
49
50  void emitPersonalityValue(MCStreamer &Streamer, const DataLayout &DL,
51                            const MCSymbol *Sym) const override;
52
53  /// Given a constant with the SectionKind, return a section that it should be
54  /// placed in.
55  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
56                                   const Constant *C,
57                                   unsigned &Align) const override;
58
59  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
60                                      const TargetMachine &TM) const override;
61
62  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
63                                    const TargetMachine &TM) const override;
64
65  MCSection *getSectionForJumpTable(const Function &F,
66                                    const TargetMachine &TM) const override;
67
68  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
69                                           const Function &F) const override;
70
71  /// Return an MCExpr to use for a reference to the specified type info global
72  /// variable from exception handling information.
73  const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,
74                                        unsigned Encoding,
75                                        const TargetMachine &TM,
76                                        MachineModuleInfo *MMI,
77                                        MCStreamer &Streamer) const override;
78
79  // The symbol that gets passed to .cfi_personality.
80  MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
81                                    const TargetMachine &TM,
82                                    MachineModuleInfo *MMI) const override;
83
84  void InitializeELF(bool UseInitArray_);
85  MCSection *getStaticCtorSection(unsigned Priority,
86                                  const MCSymbol *KeySym) const override;
87  MCSection *getStaticDtorSection(unsigned Priority,
88                                  const MCSymbol *KeySym) const override;
89
90  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
91                                       const GlobalValue *RHS,
92                                       const TargetMachine &TM) const override;
93
94  MCSection *getSectionForCommandLines() const override;
95};
96
97class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
98public:
99  TargetLoweringObjectFileMachO();
100  ~TargetLoweringObjectFileMachO() override = default;
101
102  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
103
104  /// Emit the module flags that specify the garbage collection information.
105  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
106
107  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
108                                    const TargetMachine &TM) const override;
109
110  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
111                                      const TargetMachine &TM) const override;
112
113  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
114                                   const Constant *C,
115                                   unsigned &Align) const override;
116
117  /// The mach-o version of this method defaults to returning a stub reference.
118  const MCExpr *getTTypeGlobalReference(const GlobalValue *GV,
119                                        unsigned Encoding,
120                                        const TargetMachine &TM,
121                                        MachineModuleInfo *MMI,
122                                        MCStreamer &Streamer) const override;
123
124  // The symbol that gets passed to .cfi_personality.
125  MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
126                                    const TargetMachine &TM,
127                                    MachineModuleInfo *MMI) const override;
128
129  /// Get MachO PC relative GOT entry relocation
130  const MCExpr *getIndirectSymViaGOTPCRel(const GlobalValue *GV,
131                                          const MCSymbol *Sym,
132                                          const MCValue &MV, int64_t Offset,
133                                          MachineModuleInfo *MMI,
134                                          MCStreamer &Streamer) const override;
135
136  void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,
137                         const TargetMachine &TM) const override;
138};
139
140class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {
141  mutable unsigned NextUniqueID = 0;
142
143public:
144  ~TargetLoweringObjectFileCOFF() override = default;
145
146  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
147  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
148                                      const TargetMachine &TM) const override;
149
150  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
151                                    const TargetMachine &TM) const override;
152
153  void getNameWithPrefix(SmallVectorImpl<char> &OutName, const GlobalValue *GV,
154                         const TargetMachine &TM) const override;
155
156  MCSection *getSectionForJumpTable(const Function &F,
157                                    const TargetMachine &TM) const override;
158
159  /// Emit Obj-C garbage collection and linker options.
160  void emitModuleMetadata(MCStreamer &Streamer, Module &M) const override;
161
162  MCSection *getStaticCtorSection(unsigned Priority,
163                                  const MCSymbol *KeySym) const override;
164  MCSection *getStaticDtorSection(unsigned Priority,
165                                  const MCSymbol *KeySym) const override;
166
167  void emitLinkerFlagsForGlobal(raw_ostream &OS,
168                                const GlobalValue *GV) const override;
169
170  void emitLinkerFlagsForUsed(raw_ostream &OS,
171                              const GlobalValue *GV) const override;
172
173  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
174                                       const GlobalValue *RHS,
175                                       const TargetMachine &TM) const override;
176
177  /// Given a mergeable constant with the specified size and relocation
178  /// information, return a section that it should be placed in.
179  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
180                                   const Constant *C,
181                                   unsigned &Align) const override;
182};
183
184class TargetLoweringObjectFileWasm : public TargetLoweringObjectFile {
185  mutable unsigned NextUniqueID = 0;
186
187public:
188  TargetLoweringObjectFileWasm() = default;
189  ~TargetLoweringObjectFileWasm() override = default;
190
191  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
192                                      const TargetMachine &TM) const override;
193
194  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
195                                    const TargetMachine &TM) const override;
196
197  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
198                                           const Function &F) const override;
199
200  void InitializeWasm();
201  MCSection *getStaticCtorSection(unsigned Priority,
202                                  const MCSymbol *KeySym) const override;
203  MCSection *getStaticDtorSection(unsigned Priority,
204                                  const MCSymbol *KeySym) const override;
205
206  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
207                                       const GlobalValue *RHS,
208                                       const TargetMachine &TM) const override;
209};
210
211class TargetLoweringObjectFileXCOFF : public TargetLoweringObjectFile {
212public:
213  TargetLoweringObjectFileXCOFF() = default;
214  ~TargetLoweringObjectFileXCOFF() override = default;
215
216  void Initialize(MCContext &Ctx, const TargetMachine &TM) override;
217
218  bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
219                                           const Function &F) const override;
220
221  MCSection *getExplicitSectionGlobal(const GlobalObject *GO, SectionKind Kind,
222                                      const TargetMachine &TM) const override;
223
224  MCSection *getStaticCtorSection(unsigned Priority,
225                                  const MCSymbol *KeySym) const override;
226  MCSection *getStaticDtorSection(unsigned Priority,
227                                  const MCSymbol *KeySym) const override;
228
229  const MCExpr *lowerRelativeReference(const GlobalValue *LHS,
230                                       const GlobalValue *RHS,
231                                       const TargetMachine &TM) const override;
232
233  MCSection *SelectSectionForGlobal(const GlobalObject *GO, SectionKind Kind,
234                                    const TargetMachine &TM) const override;
235
236  MCSection *getSectionForJumpTable(const Function &F,
237                                    const TargetMachine &TM) const override;
238
239  /// Given a constant with the SectionKind, return a section that it should be
240  /// placed in.
241  MCSection *getSectionForConstant(const DataLayout &DL, SectionKind Kind,
242                                   const Constant *C,
243                                   unsigned &Align) const override;
244
245  static XCOFF::StorageClass getStorageClassForGlobal(const GlobalObject *GO);
246};
247
248} // end namespace llvm
249
250#endif // LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H
251