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/StringRef.h"
19 #include "llvm/MC/SectionKind.h"
22 class MachineModuleInfo;
34 class TargetLoweringObjectFile {
37 TargetLoweringObjectFile(const TargetLoweringObjectFile&); // DO NOT IMPLEMENT
38 void operator=(const TargetLoweringObjectFile&); // DO NOT IMPLEMENT
41 TargetLoweringObjectFile();
43 /// TextSection - Section directive for standard text.
45 const MCSection *TextSection;
47 /// DataSection - Section directive for standard data.
49 const MCSection *DataSection;
51 /// BSSSection - Section that is default initialized to zero.
52 const MCSection *BSSSection;
54 /// ReadOnlySection - Section that is readonly and can contain arbitrary
55 /// initialized data. Targets are not required to have a readonly section.
56 /// If they don't, various bits of code will fall back to using the data
57 /// section for constants.
58 const MCSection *ReadOnlySection;
60 /// StaticCtorSection - This section contains the static constructor pointer
62 const MCSection *StaticCtorSection;
64 /// StaticDtorSection - This section contains the static destructor pointer
66 const MCSection *StaticDtorSection;
68 /// LSDASection - If exception handling is supported by the target, this is
69 /// the section the Language Specific Data Area information is emitted to.
70 const MCSection *LSDASection;
72 /// CompactUnwindSection - If exception handling is supported by the target
73 /// and the target can support a compact representation of the CIE and FDE,
74 /// this is the section to emit them into.
75 const MCSection *CompactUnwindSection;
77 // Dwarf sections for debug info. If a target supports debug info, these must
79 const MCSection *DwarfAbbrevSection;
80 const MCSection *DwarfInfoSection;
81 const MCSection *DwarfLineSection;
82 const MCSection *DwarfFrameSection;
83 const MCSection *DwarfPubNamesSection;
84 const MCSection *DwarfPubTypesSection;
85 const MCSection *DwarfDebugInlineSection;
86 const MCSection *DwarfStrSection;
87 const MCSection *DwarfLocSection;
88 const MCSection *DwarfARangesSection;
89 const MCSection *DwarfRangesSection;
90 const MCSection *DwarfMacroInfoSection;
92 // Extra TLS Variable Data section. If the target needs to put additional
93 // information for a TLS variable, it'll go here.
94 const MCSection *TLSExtraDataSection;
96 /// CommDirectiveSupportsAlignment - True if .comm supports alignment. This
97 /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
98 /// support alignment on comm.
99 bool CommDirectiveSupportsAlignment;
101 /// SupportsWeakEmptyEHFrame - True if target object file supports a
102 /// weak_definition of constant 0 for an omitted EH frame.
103 bool SupportsWeakOmittedEHFrame;
105 /// IsFunctionEHFrameSymbolPrivate - This flag is set to true if the
106 /// "EH_frame" symbol for EH information should be an assembler temporary (aka
107 /// private linkage, aka an L or .L label) or false if it should be a normal
108 /// non-.globl label. This defaults to true.
109 bool IsFunctionEHFrameSymbolPrivate;
112 MCContext &getContext() const { return *Ctx; }
114 virtual ~TargetLoweringObjectFile();
116 /// Initialize - this method must be called before any actual lowering is
117 /// done. This specifies the current context for codegen, and gives the
118 /// lowering implementations a chance to set up their default sections.
119 virtual void Initialize(MCContext &ctx, const TargetMachine &TM) {
123 bool isFunctionEHFrameSymbolPrivate() const {
124 return IsFunctionEHFrameSymbolPrivate;
126 bool getSupportsWeakOmittedEHFrame() const {
127 return SupportsWeakOmittedEHFrame;
129 bool getCommDirectiveSupportsAlignment() const {
130 return CommDirectiveSupportsAlignment;
133 const MCSection *getTextSection() const { return TextSection; }
134 const MCSection *getDataSection() const { return DataSection; }
135 const MCSection *getBSSSection() const { return BSSSection; }
136 const MCSection *getStaticCtorSection() const { return StaticCtorSection; }
137 const MCSection *getStaticDtorSection() const { return StaticDtorSection; }
138 const MCSection *getLSDASection() const { return LSDASection; }
139 const MCSection *getCompactUnwindSection() const{return CompactUnwindSection;}
140 virtual const MCSection *getEHFrameSection() const = 0;
141 virtual void emitPersonalityValue(MCStreamer &Streamer,
142 const TargetMachine &TM,
143 const MCSymbol *Sym) const;
144 const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
145 const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
146 const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
147 const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
148 const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
149 const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
150 const MCSection *getDwarfDebugInlineSection() const {
151 return DwarfDebugInlineSection;
153 const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
154 const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
155 const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
156 const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
157 const MCSection *getDwarfMacroInfoSection() const {
158 return DwarfMacroInfoSection;
160 const MCSection *getTLSExtraDataSection() const {
161 return TLSExtraDataSection;
163 virtual const MCSection *getWin64EHFuncTableSection(StringRef suffix)const=0;
164 virtual const MCSection *getWin64EHTableSection(StringRef suffix) const = 0;
166 /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
167 /// decide not to emit the UsedDirective for some symbols in llvm.used.
168 /// FIXME: REMOVE this (rdar://7071300)
169 virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
174 /// getSectionForConstant - Given a constant with the SectionKind, return a
175 /// section that it should be placed in.
176 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
178 /// getKindForGlobal - Classify the specified global variable into a set of
179 /// target independent categories embodied in SectionKind.
180 static SectionKind getKindForGlobal(const GlobalValue *GV,
181 const TargetMachine &TM);
183 /// SectionForGlobal - This method computes the appropriate section to emit
184 /// the specified global variable or function definition. This should not
185 /// be passed external (or available externally) globals.
186 const MCSection *SectionForGlobal(const GlobalValue *GV,
187 SectionKind Kind, Mangler *Mang,
188 const TargetMachine &TM) const;
190 /// SectionForGlobal - This method computes the appropriate section to emit
191 /// the specified global variable or function definition. This should not
192 /// be passed external (or available externally) globals.
193 const MCSection *SectionForGlobal(const GlobalValue *GV,
195 const TargetMachine &TM) const {
196 return SectionForGlobal(GV, getKindForGlobal(GV, TM), Mang, TM);
201 /// getExplicitSectionGlobal - Targets should implement this method to assign
202 /// a section to globals with an explicit section specfied. The
203 /// implementation of this method can assume that GV->hasSection() is true.
204 virtual const MCSection *
205 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
206 Mangler *Mang, const TargetMachine &TM) const = 0;
208 /// getSpecialCasedSectionGlobals - Allow the target to completely override
209 /// section assignment of a global.
210 virtual const MCSection *
211 getSpecialCasedSectionGlobals(const GlobalValue *GV, Mangler *Mang,
212 SectionKind Kind) const {
216 /// getExprForDwarfGlobalReference - Return an MCExpr to use for a reference
217 /// to the specified global variable from exception handling information.
219 virtual const MCExpr *
220 getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
221 MachineModuleInfo *MMI, unsigned Encoding,
222 MCStreamer &Streamer) const;
224 // getCFIPersonalitySymbol - The symbol that gets passed to .cfi_personality.
226 getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
227 MachineModuleInfo *MMI) const;
231 getExprForDwarfReference(const MCSymbol *Sym, unsigned Encoding,
232 MCStreamer &Streamer) const;
234 virtual unsigned getPersonalityEncoding() const;
235 virtual unsigned getLSDAEncoding() const;
236 virtual unsigned getFDEEncoding(bool CFI) const;
237 virtual unsigned getTTypeEncoding() const;
240 virtual const MCSection *
241 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
242 Mangler *Mang, const TargetMachine &TM) const;
245 } // end namespace llvm