1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
|
//===-- llvm/Target/TargetLoweringObjectFile.h - Object Info ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements classes used to handle lowerings specific to common
// object file formats.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETLOWERINGOBJECTFILE_H
#define LLVM_TARGET_TARGETLOWERINGOBJECTFILE_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/SectionKind.h"
namespace llvm {
class MachineModuleInfo;
class Mangler;
class MCContext;
class MCExpr;
class MCSection;
class MCSymbol;
class MCSymbolRefExpr;
class MCStreamer;
class MCValue;
class ConstantExpr;
class GlobalValue;
class TargetMachine;
class TargetLoweringObjectFile : public MCObjectFileInfo {
MCContext *Ctx;
TargetLoweringObjectFile(
const TargetLoweringObjectFile&) = delete;
void operator=(const TargetLoweringObjectFile&) = delete;
protected:
const DataLayout *DL;
bool SupportIndirectSymViaGOTPCRel;
bool SupportGOTPCRelWithOffset;
public:
MCContext &getContext() const { return *Ctx; }
TargetLoweringObjectFile() : MCObjectFileInfo(), Ctx(nullptr), DL(nullptr),
SupportIndirectSymViaGOTPCRel(false),
SupportGOTPCRelWithOffset(true) {}
virtual ~TargetLoweringObjectFile();
/// This method must be called before any actual lowering is done. This
/// specifies the current context for codegen, and gives the lowering
/// implementations a chance to set up their default sections.
virtual void Initialize(MCContext &ctx, const TargetMachine &TM);
virtual void emitPersonalityValue(MCStreamer &Streamer,
const TargetMachine &TM,
const MCSymbol *Sym) const;
/// Extract the dependent library name from a linker option string. Returns
/// StringRef() if the option does not specify a library.
virtual StringRef getDepLibFromLinkerOpt(StringRef LinkerOption) const {
return StringRef();
}
/// Emit the module flags that the platform cares about.
virtual void emitModuleFlags(MCStreamer &Streamer,
ArrayRef<Module::ModuleFlagEntry> Flags,
Mangler &Mang, const TargetMachine &TM) const {}
/// Given a constant with the SectionKind, return a section that it should be
/// placed in.
virtual const MCSection *getSectionForConstant(SectionKind Kind,
const Constant *C) const;
/// Classify the specified global variable into a set of target independent
/// categories embodied in SectionKind.
static SectionKind getKindForGlobal(const GlobalValue *GV,
const TargetMachine &TM);
/// This method computes the appropriate section to emit the specified global
/// variable or function definition. This should not be passed external (or
/// available externally) globals.
const MCSection *SectionForGlobal(const GlobalValue *GV,
SectionKind Kind, Mangler &Mang,
const TargetMachine &TM) const;
/// This method computes the appropriate section to emit the specified global
/// variable or function definition. This should not be passed external (or
/// available externally) globals.
const MCSection *SectionForGlobal(const GlobalValue *GV,
Mangler &Mang,
const TargetMachine &TM) const {
return SectionForGlobal(GV, getKindForGlobal(GV, TM), Mang, TM);
}
virtual void getNameWithPrefix(SmallVectorImpl<char> &OutName,
const GlobalValue *GV,
bool CannotUsePrivateLabel, Mangler &Mang,
const TargetMachine &TM) const;
virtual const MCSection *
getSectionForJumpTable(const Function &F, Mangler &Mang,
const TargetMachine &TM) const;
virtual bool shouldPutJumpTableInFunctionSection(bool UsesLabelDifference,
const Function &F) const;
/// Targets should implement this method to assign a section to globals with
/// an explicit section specfied. The implementation of this method can
/// assume that GV->hasSection() is true.
virtual const MCSection *
getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const = 0;
/// Allow the target to completely override section assignment of a global.
virtual const MCSection *getSpecialCasedSectionGlobals(const GlobalValue *GV,
SectionKind Kind,
Mangler &Mang) const {
return nullptr;
}
/// Return an MCExpr to use for a reference to the specified global variable
/// from exception handling information.
virtual const MCExpr *
getTTypeGlobalReference(const GlobalValue *GV, unsigned Encoding,
Mangler &Mang, const TargetMachine &TM,
MachineModuleInfo *MMI, MCStreamer &Streamer) const;
/// Return the MCSymbol for a private symbol with global value name as its
/// base, with the specified suffix.
MCSymbol *getSymbolWithGlobalValueBase(const GlobalValue *GV,
StringRef Suffix, Mangler &Mang,
const TargetMachine &TM) const;
// The symbol that gets passed to .cfi_personality.
virtual MCSymbol *getCFIPersonalitySymbol(const GlobalValue *GV,
Mangler &Mang,
const TargetMachine &TM,
MachineModuleInfo *MMI) const;
const MCExpr *
getTTypeReference(const MCSymbolRefExpr *Sym, unsigned Encoding,
MCStreamer &Streamer) const;
virtual const MCSection *getStaticCtorSection(unsigned Priority,
const MCSymbol *KeySym) const {
return StaticCtorSection;
}
virtual const MCSection *getStaticDtorSection(unsigned Priority,
const MCSymbol *KeySym) const {
return StaticDtorSection;
}
/// \brief Create a symbol reference to describe the given TLS variable when
/// emitting the address in debug info.
virtual const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const;
virtual const MCExpr *
getExecutableRelativeSymbol(const ConstantExpr *CE, Mangler &Mang,
const TargetMachine &TM) const {
return nullptr;
}
/// \brief Target supports replacing a data "PC"-relative access to a symbol
/// through another symbol, by accessing the later via a GOT entry instead?
bool supportIndirectSymViaGOTPCRel() const {
return SupportIndirectSymViaGOTPCRel;
}
/// \brief Target GOT "PC"-relative relocation supports encoding an additional
/// binary expression with an offset?
bool supportGOTPCRelWithOffset() const {
return SupportGOTPCRelWithOffset;
}
/// \brief Get the target specific PC relative GOT entry relocation
virtual const MCExpr *getIndirectSymViaGOTPCRel(const MCSymbol *Sym,
const MCValue &MV,
int64_t Offset,
MachineModuleInfo *MMI,
MCStreamer &Streamer) const {
return nullptr;
}
protected:
virtual const MCSection *
SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
Mangler &Mang, const TargetMachine &TM) const = 0;
};
} // end namespace llvm
#endif
|
