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;
111 /// SupportsCompactUnwindInfo - This flag is set to true if the CIE and FDE
112 /// information should be emitted in a compact form.
113 bool SupportsCompactUnwindInfo;
116 MCContext &getContext() const { return *Ctx; }
118 virtual ~TargetLoweringObjectFile();
120 /// Initialize - this method must be called before any actual lowering is
121 /// done. This specifies the current context for codegen, and gives the
122 /// lowering implementations a chance to set up their default sections.
123 virtual void Initialize(MCContext &ctx, const TargetMachine &TM) {
127 bool isFunctionEHFrameSymbolPrivate() const {
128 return IsFunctionEHFrameSymbolPrivate;
130 bool getSupportsWeakOmittedEHFrame() const {
131 return SupportsWeakOmittedEHFrame;
133 bool getCommDirectiveSupportsAlignment() const {
134 return CommDirectiveSupportsAlignment;
136 bool getSupportsCompactUnwindInfo() const {
137 return SupportsCompactUnwindInfo;
140 const MCSection *getTextSection() const { return TextSection; }
141 const MCSection *getDataSection() const { return DataSection; }
142 const MCSection *getBSSSection() const { return BSSSection; }
143 const MCSection *getStaticCtorSection() const { return StaticCtorSection; }
144 const MCSection *getStaticDtorSection() const { return StaticDtorSection; }
145 const MCSection *getLSDASection() const { return LSDASection; }
146 const MCSection *getCompactUnwindSection() const{return CompactUnwindSection;}
147 virtual const MCSection *getEHFrameSection() const = 0;
148 virtual void emitPersonalityValue(MCStreamer &Streamer,
149 const TargetMachine &TM,
150 const MCSymbol *Sym) const;
151 const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
152 const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
153 const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
154 const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
155 const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
156 const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
157 const MCSection *getDwarfDebugInlineSection() const {
158 return DwarfDebugInlineSection;
160 const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
161 const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
162 const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
163 const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
164 const MCSection *getDwarfMacroInfoSection() const {
165 return DwarfMacroInfoSection;
167 const MCSection *getTLSExtraDataSection() const {
168 return TLSExtraDataSection;
170 virtual const MCSection *getWin64EHFuncTableSection(StringRef suffix)const=0;
171 virtual const MCSection *getWin64EHTableSection(StringRef suffix) const = 0;
173 /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
174 /// decide not to emit the UsedDirective for some symbols in llvm.used.
175 /// FIXME: REMOVE this (rdar://7071300)
176 virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
181 /// getSectionForConstant - Given a constant with the SectionKind, return a
182 /// section that it should be placed in.
183 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
185 /// getKindForGlobal - Classify the specified global variable into a set of
186 /// target independent categories embodied in SectionKind.
187 static SectionKind getKindForGlobal(const GlobalValue *GV,
188 const TargetMachine &TM);
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,
194 SectionKind Kind, Mangler *Mang,
195 const TargetMachine &TM) const;
197 /// SectionForGlobal - This method computes the appropriate section to emit
198 /// the specified global variable or function definition. This should not
199 /// be passed external (or available externally) globals.
200 const MCSection *SectionForGlobal(const GlobalValue *GV,
202 const TargetMachine &TM) const {
203 return SectionForGlobal(GV, getKindForGlobal(GV, TM), Mang, TM);
208 /// getExplicitSectionGlobal - Targets should implement this method to assign
209 /// a section to globals with an explicit section specfied. The
210 /// implementation of this method can assume that GV->hasSection() is true.
211 virtual const MCSection *
212 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
213 Mangler *Mang, const TargetMachine &TM) const = 0;
215 /// getSpecialCasedSectionGlobals - Allow the target to completely override
216 /// section assignment of a global.
217 virtual const MCSection *
218 getSpecialCasedSectionGlobals(const GlobalValue *GV, Mangler *Mang,
219 SectionKind Kind) const {
223 /// getExprForDwarfGlobalReference - Return an MCExpr to use for a reference
224 /// to the specified global variable from exception handling information.
226 virtual const MCExpr *
227 getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
228 MachineModuleInfo *MMI, unsigned Encoding,
229 MCStreamer &Streamer) const;
231 // getCFIPersonalitySymbol - The symbol that gets passed to .cfi_personality.
233 getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
234 MachineModuleInfo *MMI) const;
238 getExprForDwarfReference(const MCSymbol *Sym, unsigned Encoding,
239 MCStreamer &Streamer) const;
241 virtual unsigned getPersonalityEncoding() const;
242 virtual unsigned getLSDAEncoding() const;
243 virtual unsigned getFDEEncoding(bool CFI) const;
244 virtual unsigned getTTypeEncoding() const;
247 virtual const MCSection *
248 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
249 Mangler *Mang, const TargetMachine &TM) const;
252 } // end namespace llvm