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;
33 class TargetLoweringObjectFile {
36 TargetLoweringObjectFile(const TargetLoweringObjectFile&); // DO NOT IMPLEMENT
37 void operator=(const TargetLoweringObjectFile&); // DO NOT IMPLEMENT
40 TargetLoweringObjectFile();
42 /// TextSection - Section directive for standard text.
44 const MCSection *TextSection;
46 /// DataSection - Section directive for standard data.
48 const MCSection *DataSection;
50 /// BSSSection - Section that is default initialized to zero.
51 const MCSection *BSSSection;
53 /// ReadOnlySection - Section that is readonly and can contain arbitrary
54 /// initialized data. Targets are not required to have a readonly section.
55 /// If they don't, various bits of code will fall back to using the data
56 /// section for constants.
57 const MCSection *ReadOnlySection;
59 /// StaticCtorSection - This section contains the static constructor pointer
61 const MCSection *StaticCtorSection;
63 /// StaticDtorSection - This section contains the static destructor pointer
65 const MCSection *StaticDtorSection;
67 /// LSDASection - If exception handling is supported by the target, this is
68 /// the section the Language Specific Data Area information is emitted to.
69 const MCSection *LSDASection;
71 /// EHFrameSection - If exception handling is supported by the target, this is
72 /// the section the EH Frame is emitted to.
73 const MCSection *EHFrameSection;
75 // Dwarf sections for debug info. If a target supports debug info, these must
77 const MCSection *DwarfAbbrevSection;
78 const MCSection *DwarfInfoSection;
79 const MCSection *DwarfLineSection;
80 const MCSection *DwarfFrameSection;
81 const MCSection *DwarfPubNamesSection;
82 const MCSection *DwarfPubTypesSection;
83 const MCSection *DwarfDebugInlineSection;
84 const MCSection *DwarfStrSection;
85 const MCSection *DwarfLocSection;
86 const MCSection *DwarfARangesSection;
87 const MCSection *DwarfRangesSection;
88 const MCSection *DwarfMacroInfoSection;
92 MCContext &getContext() const { return *Ctx; }
95 virtual ~TargetLoweringObjectFile();
97 /// Initialize - this method must be called before any actual lowering is
98 /// done. This specifies the current context for codegen, and gives the
99 /// lowering implementations a chance to set up their default sections.
100 virtual void Initialize(MCContext &ctx, const TargetMachine &TM) {
105 const MCSection *getTextSection() const { return TextSection; }
106 const MCSection *getDataSection() const { return DataSection; }
107 const MCSection *getBSSSection() const { return BSSSection; }
108 const MCSection *getStaticCtorSection() const { return StaticCtorSection; }
109 const MCSection *getStaticDtorSection() const { return StaticDtorSection; }
110 const MCSection *getLSDASection() const { return LSDASection; }
111 const MCSection *getEHFrameSection() const { return EHFrameSection; }
112 const MCSection *getDwarfAbbrevSection() const { return DwarfAbbrevSection; }
113 const MCSection *getDwarfInfoSection() const { return DwarfInfoSection; }
114 const MCSection *getDwarfLineSection() const { return DwarfLineSection; }
115 const MCSection *getDwarfFrameSection() const { return DwarfFrameSection; }
116 const MCSection *getDwarfPubNamesSection() const{return DwarfPubNamesSection;}
117 const MCSection *getDwarfPubTypesSection() const{return DwarfPubTypesSection;}
118 const MCSection *getDwarfDebugInlineSection() const {
119 return DwarfDebugInlineSection;
121 const MCSection *getDwarfStrSection() const { return DwarfStrSection; }
122 const MCSection *getDwarfLocSection() const { return DwarfLocSection; }
123 const MCSection *getDwarfARangesSection() const { return DwarfARangesSection;}
124 const MCSection *getDwarfRangesSection() const { return DwarfRangesSection; }
125 const MCSection *getDwarfMacroInfoSection() const {
126 return DwarfMacroInfoSection;
129 /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
130 /// decide not to emit the UsedDirective for some symbols in llvm.used.
131 /// FIXME: REMOVE this (rdar://7071300)
132 virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
137 /// getSectionForConstant - Given a constant with the SectionKind, return a
138 /// section that it should be placed in.
139 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
141 /// getKindForGlobal - Classify the specified global variable into a set of
142 /// target independent categories embodied in SectionKind.
143 static SectionKind getKindForGlobal(const GlobalValue *GV,
144 const TargetMachine &TM);
146 /// SectionForGlobal - This method computes the appropriate section to emit
147 /// the specified global variable or function definition. This should not
148 /// be passed external (or available externally) globals.
149 const MCSection *SectionForGlobal(const GlobalValue *GV,
150 SectionKind Kind, Mangler *Mang,
151 const TargetMachine &TM) const;
153 /// SectionForGlobal - This method computes the appropriate section to emit
154 /// the specified global variable or function definition. This should not
155 /// be passed external (or available externally) globals.
156 const MCSection *SectionForGlobal(const GlobalValue *GV,
158 const TargetMachine &TM) const {
159 return SectionForGlobal(GV, getKindForGlobal(GV, TM), Mang, TM);
164 /// getExplicitSectionGlobal - Targets should implement this method to assign
165 /// a section to globals with an explicit section specfied. The
166 /// implementation of this method can assume that GV->hasSection() is true.
167 virtual const MCSection *
168 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
169 Mangler *Mang, const TargetMachine &TM) const = 0;
171 /// getSpecialCasedSectionGlobals - Allow the target to completely override
172 /// section assignment of a global.
173 virtual const MCSection *
174 getSpecialCasedSectionGlobals(const GlobalValue *GV, Mangler *Mang,
175 SectionKind Kind) const {
179 /// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a reference
180 /// to the specified global variable from exception handling information.
182 virtual const MCExpr *
183 getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
184 MachineModuleInfo *MMI, unsigned Encoding) const;
186 virtual const MCExpr *
187 getSymbolForDwarfReference(const MCSymbol *Sym, MachineModuleInfo *MMI,
188 unsigned Encoding) const;
190 virtual unsigned getPersonalityEncoding() const;
191 virtual unsigned getLSDAEncoding() const;
192 virtual unsigned getFDEEncoding() const;
193 virtual unsigned getTTypeEncoding() const;
196 virtual const MCSection *
197 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
198 Mangler *Mang, const TargetMachine &TM) const;
204 class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
205 mutable void *UniquingMap;
207 /// TLSDataSection - Section directive for Thread Local data.
209 const MCSection *TLSDataSection; // Defaults to ".tdata".
211 /// TLSBSSSection - Section directive for Thread Local uninitialized data.
212 /// Null if this target doesn't support a BSS section.
214 const MCSection *TLSBSSSection; // Defaults to ".tbss".
216 const MCSection *DataRelSection;
217 const MCSection *DataRelLocalSection;
218 const MCSection *DataRelROSection;
219 const MCSection *DataRelROLocalSection;
221 const MCSection *MergeableConst4Section;
222 const MCSection *MergeableConst8Section;
223 const MCSection *MergeableConst16Section;
226 const MCSection *getELFSection(StringRef Section, unsigned Type,
227 unsigned Flags, SectionKind Kind,
228 bool IsExplicit = false) const;
230 TargetLoweringObjectFileELF() : UniquingMap(0) {}
231 ~TargetLoweringObjectFileELF();
233 virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
235 const MCSection *getDataRelSection() const { return DataRelSection; }
237 /// getSectionForConstant - Given a constant with the SectionKind, return a
238 /// section that it should be placed in.
239 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
242 virtual const MCSection *
243 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
244 Mangler *Mang, const TargetMachine &TM) const;
246 virtual const MCSection *
247 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
248 Mangler *Mang, const TargetMachine &TM) const;
250 /// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a reference
251 /// to the specified global variable from exception handling information.
253 virtual const MCExpr *
254 getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
255 MachineModuleInfo *MMI, unsigned Encoding) const;
260 class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
261 mutable void *UniquingMap;
263 const MCSection *CStringSection;
264 const MCSection *UStringSection;
265 const MCSection *TextCoalSection;
266 const MCSection *ConstTextCoalSection;
267 const MCSection *ConstDataCoalSection;
268 const MCSection *ConstDataSection;
269 const MCSection *DataCoalSection;
270 const MCSection *DataCommonSection;
271 const MCSection *DataBSSSection;
272 const MCSection *FourByteConstantSection;
273 const MCSection *EightByteConstantSection;
274 const MCSection *SixteenByteConstantSection;
276 const MCSection *LazySymbolPointerSection;
277 const MCSection *NonLazySymbolPointerSection;
279 TargetLoweringObjectFileMachO() : UniquingMap(0) {}
280 ~TargetLoweringObjectFileMachO();
282 virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
284 virtual const MCSection *
285 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
286 Mangler *Mang, const TargetMachine &TM) const;
288 virtual const MCSection *
289 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
290 Mangler *Mang, const TargetMachine &TM) const;
292 virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
294 /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
295 /// decide not to emit the UsedDirective for some symbols in llvm.used.
296 /// FIXME: REMOVE this (rdar://7071300)
297 virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
300 /// getMachOSection - Return the MCSection for the specified mach-o section.
301 /// This requires the operands to be valid.
302 const MCSectionMachO *getMachOSection(StringRef Segment,
304 unsigned TypeAndAttributes,
305 SectionKind K) const {
306 return getMachOSection(Segment, Section, TypeAndAttributes, 0, K);
308 const MCSectionMachO *getMachOSection(StringRef Segment,
310 unsigned TypeAndAttributes,
312 SectionKind K) const;
314 /// getTextCoalSection - Return the "__TEXT,__textcoal_nt" section we put weak
315 /// text symbols into.
316 const MCSection *getTextCoalSection() const {
317 return TextCoalSection;
320 /// getConstTextCoalSection - Return the "__TEXT,__const_coal" section
321 /// we put weak read-only symbols into.
322 const MCSection *getConstTextCoalSection() const {
323 return ConstTextCoalSection;
326 /// getLazySymbolPointerSection - Return the section corresponding to
327 /// the .lazy_symbol_pointer directive.
328 const MCSection *getLazySymbolPointerSection() const {
329 return LazySymbolPointerSection;
332 /// getNonLazySymbolPointerSection - Return the section corresponding to
333 /// the .non_lazy_symbol_pointer directive.
334 const MCSection *getNonLazySymbolPointerSection() const {
335 return NonLazySymbolPointerSection;
338 /// getSymbolForDwarfGlobalReference - The mach-o version of this method
339 /// defaults to returning a stub reference.
340 virtual const MCExpr *
341 getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
342 MachineModuleInfo *MMI, unsigned Encoding) const;
347 class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {
348 mutable void *UniquingMap;
350 TargetLoweringObjectFileCOFF() : UniquingMap(0) {}
351 ~TargetLoweringObjectFileCOFF();
353 virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
355 virtual const MCSection *
356 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
357 Mangler *Mang, const TargetMachine &TM) const;
359 virtual const MCSection *
360 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
361 Mangler *Mang, const TargetMachine &TM) const;
363 /// getCOFFSection - Return the MCSection for the specified COFF section.
364 /// FIXME: Switch this to a semantic view eventually.
365 const MCSection *getCOFFSection(StringRef Name, bool isDirective,
366 SectionKind K) const;
369 } // end namespace llvm