1 //===-- llvm/Target/TargetLoweringObjectFile.h - Object Info ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements classes used to handle lowerings specific to common
11 // object file formats.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_TARGET_TARGETLOWERINGOBJECTFILE_H
16 #define LLVM_TARGET_TARGETLOWERINGOBJECTFILE_H
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/MC/MCObjectFileInfo.h"
21 #include "llvm/MC/SectionKind.h"
24 class MachineModuleInfo;
30 class MCSymbolRefExpr;
36 class TargetLoweringObjectFile : public MCObjectFileInfo {
40 TargetLoweringObjectFile(
41 const TargetLoweringObjectFile&) LLVM_DELETED_FUNCTION;
42 void operator=(const TargetLoweringObjectFile&) LLVM_DELETED_FUNCTION;
45 MCContext &getContext() const { return *Ctx; }
47 TargetLoweringObjectFile() : MCObjectFileInfo(), Ctx(0), DL(0) {}
49 virtual ~TargetLoweringObjectFile();
51 /// This method must be called before any actual lowering is done. This
52 /// specifies the current context for codegen, and gives the lowering
53 /// implementations a chance to set up their default sections.
54 virtual void Initialize(MCContext &ctx, const TargetMachine &TM);
56 virtual void emitPersonalityValue(MCStreamer &Streamer,
57 const TargetMachine &TM,
58 const MCSymbol *Sym) const;
60 /// Extract the dependent library name from a linker option string. Returns
61 /// StringRef() if the option does not specify a library.
62 virtual StringRef getDepLibFromLinkerOpt(StringRef LinkerOption) const {
66 /// Emit the module flags that the platform cares about.
67 virtual void emitModuleFlags(MCStreamer &,
68 ArrayRef<Module::ModuleFlagEntry>,
69 Mangler *, const TargetMachine &) const {
72 /// This hook allows targets to selectively decide not to emit the
73 /// UsedDirective for some symbols in llvm.used.
74 /// FIXME: REMOVE this (rdar://7071300)
75 virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
80 /// Given a constant with the SectionKind, return a section that it should be
82 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
84 /// Classify the specified global variable into a set of target independent
85 /// categories embodied in SectionKind.
86 static SectionKind getKindForGlobal(const GlobalValue *GV,
87 const TargetMachine &TM);
89 /// This method computes the appropriate section to emit the specified global
90 /// variable or function definition. This should not be passed external (or
91 /// available externally) globals.
92 const MCSection *SectionForGlobal(const GlobalValue *GV,
93 SectionKind Kind, Mangler *Mang,
94 const TargetMachine &TM) const;
96 /// This method computes the appropriate section to emit the specified global
97 /// variable or function definition. This should not be passed external (or
98 /// available externally) globals.
99 const MCSection *SectionForGlobal(const GlobalValue *GV,
101 const TargetMachine &TM) const {
102 return SectionForGlobal(GV, getKindForGlobal(GV, TM), Mang, TM);
105 /// Targets should implement this method to assign a section to globals with
106 /// an explicit section specfied. The implementation of this method can
107 /// assume that GV->hasSection() is true.
108 virtual const MCSection *
109 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
110 Mangler *Mang, const TargetMachine &TM) const = 0;
112 /// Allow the target to completely override section assignment of a global.
113 virtual const MCSection *
114 getSpecialCasedSectionGlobals(const GlobalValue *GV, Mangler *Mang,
115 SectionKind Kind) const {
119 /// Return an MCExpr to use for a reference to the specified global variable
120 /// from exception handling information.
121 virtual const MCExpr *
122 getTTypeGlobalReference(const GlobalValue *GV, Mangler *Mang,
123 MachineModuleInfo *MMI, unsigned Encoding,
124 MCStreamer &Streamer) const;
126 /// Return the MCSymbol for the specified global value. This symbol is the
127 /// main label that is the address of the global
128 MCSymbol *getSymbol(Mangler &M, const GlobalValue *GV) const;
130 /// Return the MCSymbol for a private symbol with global value name as its
131 /// base, with the specified suffix.
132 MCSymbol *getSymbolWithGlobalValueBase(Mangler &M, const GlobalValue *GV,
133 StringRef Suffix) const;
135 // The symbol that gets passed to .cfi_personality.
137 getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
138 MachineModuleInfo *MMI) const;
141 getTTypeReference(const MCSymbolRefExpr *Sym, unsigned Encoding,
142 MCStreamer &Streamer) const;
144 virtual const MCSection *
145 getStaticCtorSection(unsigned Priority = 65535) const {
147 return StaticCtorSection;
149 virtual const MCSection *
150 getStaticDtorSection(unsigned Priority = 65535) const {
152 return StaticDtorSection;
155 /// \brief Create a symbol reference to describe the given TLS variable when
156 /// emitting the address in debug info.
157 virtual const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const;
159 virtual const MCExpr *
160 getExecutableRelativeSymbol(const ConstantExpr *CE, Mangler *Mang) const {
165 virtual const MCSection *
166 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
167 Mangler *Mang, const TargetMachine &TM) const;
170 } // end namespace llvm