1 //===-- llvm/CodeGen/TargetLoweringObjectFileImpl.cpp - Object File Info --===//
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 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
16 #include "llvm/ADT/SmallString.h"
17 #include "llvm/ADT/StringExtras.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DataLayout.h"
22 #include "llvm/IR/DerivedTypes.h"
23 #include "llvm/IR/Function.h"
24 #include "llvm/IR/GlobalVariable.h"
25 #include "llvm/IR/Mangler.h"
26 #include "llvm/IR/Module.h"
27 #include "llvm/MC/MCContext.h"
28 #include "llvm/MC/MCExpr.h"
29 #include "llvm/MC/MCSectionCOFF.h"
30 #include "llvm/MC/MCSectionELF.h"
31 #include "llvm/MC/MCSectionMachO.h"
32 #include "llvm/MC/MCStreamer.h"
33 #include "llvm/MC/MCSymbol.h"
34 #include "llvm/Support/Dwarf.h"
35 #include "llvm/Support/ELF.h"
36 #include "llvm/Support/ErrorHandling.h"
37 #include "llvm/Support/raw_ostream.h"
38 #include "llvm/Target/TargetMachine.h"
40 using namespace dwarf;
42 //===----------------------------------------------------------------------===//
44 //===----------------------------------------------------------------------===//
47 TargetLoweringObjectFileELF::getCFIPersonalitySymbol(const GlobalValue *GV,
49 MachineModuleInfo *MMI) const {
50 unsigned Encoding = getPersonalityEncoding();
51 switch (Encoding & 0x70) {
53 report_fatal_error("We do not support this DWARF encoding yet!");
54 case dwarf::DW_EH_PE_absptr:
55 return getSymbol(*Mang, GV);
56 case dwarf::DW_EH_PE_pcrel: {
57 return getContext().GetOrCreateSymbol(StringRef("DW.ref.") +
58 getSymbol(*Mang, GV)->getName());
63 void TargetLoweringObjectFileELF::emitPersonalityValue(MCStreamer &Streamer,
64 const TargetMachine &TM,
65 const MCSymbol *Sym) const {
66 SmallString<64> NameData("DW.ref.");
67 NameData += Sym->getName();
68 MCSymbol *Label = getContext().GetOrCreateSymbol(NameData);
69 Streamer.EmitSymbolAttribute(Label, MCSA_Hidden);
70 Streamer.EmitSymbolAttribute(Label, MCSA_Weak);
71 StringRef Prefix = ".data.";
72 NameData.insert(NameData.begin(), Prefix.begin(), Prefix.end());
73 unsigned Flags = ELF::SHF_ALLOC | ELF::SHF_WRITE | ELF::SHF_GROUP;
74 const MCSection *Sec = getContext().getELFSection(NameData,
77 SectionKind::getDataRel(),
79 unsigned Size = TM.getDataLayout()->getPointerSize();
80 Streamer.SwitchSection(Sec);
81 Streamer.EmitValueToAlignment(TM.getDataLayout()->getPointerABIAlignment());
82 Streamer.EmitSymbolAttribute(Label, MCSA_ELF_TypeObject);
83 const MCExpr *E = MCConstantExpr::Create(Size, getContext());
84 Streamer.EmitELFSize(Label, E);
85 Streamer.EmitLabel(Label);
87 Streamer.EmitSymbolValue(Sym, Size);
90 const MCExpr *TargetLoweringObjectFileELF::
91 getTTypeGlobalReference(const GlobalValue *GV, Mangler *Mang,
92 MachineModuleInfo *MMI, unsigned Encoding,
93 MCStreamer &Streamer) const {
95 if (Encoding & dwarf::DW_EH_PE_indirect) {
96 MachineModuleInfoELF &ELFMMI = MMI->getObjFileInfo<MachineModuleInfoELF>();
98 MCSymbol *SSym = getSymbolWithGlobalValueBase(*Mang, GV, ".DW.stub");
100 // Add information about the stub reference to ELFMMI so that the stub
101 // gets emitted by the asmprinter.
102 MachineModuleInfoImpl::StubValueTy &StubSym = ELFMMI.getGVStubEntry(SSym);
103 if (StubSym.getPointer() == 0) {
104 MCSymbol *Sym = getSymbol(*Mang, GV);
105 StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
108 return TargetLoweringObjectFile::
109 getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()),
110 Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
113 return TargetLoweringObjectFile::
114 getTTypeGlobalReference(GV, Mang, MMI, Encoding, Streamer);
118 getELFKindForNamedSection(StringRef Name, SectionKind K) {
119 // N.B.: The defaults used in here are no the same ones used in MC.
120 // We follow gcc, MC follows gas. For example, given ".section .eh_frame",
121 // both gas and MC will produce a section with no flags. Given
122 // section(".eh_frame") gcc will produce:
124 // .section .eh_frame,"a",@progbits
125 if (Name.empty() || Name[0] != '.') return K;
127 // Some lame default implementation based on some magic section names.
128 if (Name == ".bss" ||
129 Name.startswith(".bss.") ||
130 Name.startswith(".gnu.linkonce.b.") ||
131 Name.startswith(".llvm.linkonce.b.") ||
133 Name.startswith(".sbss.") ||
134 Name.startswith(".gnu.linkonce.sb.") ||
135 Name.startswith(".llvm.linkonce.sb."))
136 return SectionKind::getBSS();
138 if (Name == ".tdata" ||
139 Name.startswith(".tdata.") ||
140 Name.startswith(".gnu.linkonce.td.") ||
141 Name.startswith(".llvm.linkonce.td."))
142 return SectionKind::getThreadData();
144 if (Name == ".tbss" ||
145 Name.startswith(".tbss.") ||
146 Name.startswith(".gnu.linkonce.tb.") ||
147 Name.startswith(".llvm.linkonce.tb."))
148 return SectionKind::getThreadBSS();
154 static unsigned getELFSectionType(StringRef Name, SectionKind K) {
156 if (Name == ".init_array")
157 return ELF::SHT_INIT_ARRAY;
159 if (Name == ".fini_array")
160 return ELF::SHT_FINI_ARRAY;
162 if (Name == ".preinit_array")
163 return ELF::SHT_PREINIT_ARRAY;
165 if (K.isBSS() || K.isThreadBSS())
166 return ELF::SHT_NOBITS;
168 return ELF::SHT_PROGBITS;
173 getELFSectionFlags(SectionKind K) {
177 Flags |= ELF::SHF_ALLOC;
180 Flags |= ELF::SHF_EXECINSTR;
183 Flags |= ELF::SHF_WRITE;
185 if (K.isThreadLocal())
186 Flags |= ELF::SHF_TLS;
188 // K.isMergeableConst() is left out to honour PR4650
189 if (K.isMergeableCString() || K.isMergeableConst4() ||
190 K.isMergeableConst8() || K.isMergeableConst16())
191 Flags |= ELF::SHF_MERGE;
193 if (K.isMergeableCString())
194 Flags |= ELF::SHF_STRINGS;
200 const MCSection *TargetLoweringObjectFileELF::
201 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
202 Mangler *Mang, const TargetMachine &TM) const {
203 StringRef SectionName = GV->getSection();
205 // Infer section flags from the section name if we can.
206 Kind = getELFKindForNamedSection(SectionName, Kind);
208 return getContext().getELFSection(SectionName,
209 getELFSectionType(SectionName, Kind),
210 getELFSectionFlags(Kind), Kind);
213 /// getSectionPrefixForGlobal - Return the section prefix name used by options
214 /// FunctionsSections and DataSections.
215 static const char *getSectionPrefixForGlobal(SectionKind Kind) {
216 if (Kind.isText()) return ".text.";
217 if (Kind.isReadOnly()) return ".rodata.";
218 if (Kind.isBSS()) return ".bss.";
220 if (Kind.isThreadData()) return ".tdata.";
221 if (Kind.isThreadBSS()) return ".tbss.";
223 if (Kind.isDataNoRel()) return ".data.";
224 if (Kind.isDataRelLocal()) return ".data.rel.local.";
225 if (Kind.isDataRel()) return ".data.rel.";
226 if (Kind.isReadOnlyWithRelLocal()) return ".data.rel.ro.local.";
228 assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
229 return ".data.rel.ro.";
233 const MCSection *TargetLoweringObjectFileELF::
234 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
235 Mangler *Mang, TargetMachine &TM) const {
236 // If we have -ffunction-section or -fdata-section then we should emit the
237 // global value to a uniqued section specifically for it.
238 bool EmitUniquedSection;
240 EmitUniquedSection = TM.getFunctionSections();
242 EmitUniquedSection = TM.getDataSections();
244 // If this global is linkonce/weak and the target handles this by emitting it
245 // into a 'uniqued' section name, create and return the section now.
246 if ((GV->isWeakForLinker() || EmitUniquedSection) &&
249 Prefix = getSectionPrefixForGlobal(Kind);
251 SmallString<128> Name(Prefix, Prefix+strlen(Prefix));
252 MCSymbol *Sym = getSymbol(*Mang, GV);
253 Name.append(Sym->getName().begin(), Sym->getName().end());
254 StringRef Group = "";
255 unsigned Flags = getELFSectionFlags(Kind);
256 if (GV->isWeakForLinker()) {
257 Group = Sym->getName();
258 Flags |= ELF::SHF_GROUP;
261 // Set that we've used a unique section name in the target machine.
262 TM.setDebugUseUniqueSections(true);
263 return getContext().getELFSection(Name.str(),
264 getELFSectionType(Name.str(), Kind),
265 Flags, Kind, 0, Group);
268 if (Kind.isText()) return TextSection;
270 if (Kind.isMergeable1ByteCString() ||
271 Kind.isMergeable2ByteCString() ||
272 Kind.isMergeable4ByteCString()) {
274 // We also need alignment here.
275 // FIXME: this is getting the alignment of the character, not the
276 // alignment of the global!
278 TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV));
280 const char *SizeSpec = ".rodata.str1.";
281 if (Kind.isMergeable2ByteCString())
282 SizeSpec = ".rodata.str2.";
283 else if (Kind.isMergeable4ByteCString())
284 SizeSpec = ".rodata.str4.";
286 assert(Kind.isMergeable1ByteCString() && "unknown string width");
289 std::string Name = SizeSpec + utostr(Align);
290 return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
297 if (Kind.isMergeableConst()) {
298 if (Kind.isMergeableConst4() && MergeableConst4Section)
299 return MergeableConst4Section;
300 if (Kind.isMergeableConst8() && MergeableConst8Section)
301 return MergeableConst8Section;
302 if (Kind.isMergeableConst16() && MergeableConst16Section)
303 return MergeableConst16Section;
304 return ReadOnlySection; // .const
307 if (Kind.isReadOnly()) return ReadOnlySection;
309 if (Kind.isThreadData()) return TLSDataSection;
310 if (Kind.isThreadBSS()) return TLSBSSSection;
312 // Note: we claim that common symbols are put in BSSSection, but they are
313 // really emitted with the magic .comm directive, which creates a symbol table
314 // entry but not a section.
315 if (Kind.isBSS() || Kind.isCommon()) return BSSSection;
317 if (Kind.isDataNoRel()) return DataSection;
318 if (Kind.isDataRelLocal()) return DataRelLocalSection;
319 if (Kind.isDataRel()) return DataRelSection;
320 if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
322 assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
323 return DataRelROSection;
326 /// getSectionForConstant - Given a mergeable constant with the
327 /// specified size and relocation information, return a section that it
328 /// should be placed in.
329 const MCSection *TargetLoweringObjectFileELF::
330 getSectionForConstant(SectionKind Kind) const {
331 if (Kind.isMergeableConst4() && MergeableConst4Section)
332 return MergeableConst4Section;
333 if (Kind.isMergeableConst8() && MergeableConst8Section)
334 return MergeableConst8Section;
335 if (Kind.isMergeableConst16() && MergeableConst16Section)
336 return MergeableConst16Section;
337 if (Kind.isReadOnly())
338 return ReadOnlySection;
340 if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
341 assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
342 return DataRelROSection;
346 TargetLoweringObjectFileELF::getStaticCtorSection(unsigned Priority) const {
347 // The default scheme is .ctor / .dtor, so we have to invert the priority
349 if (Priority == 65535)
350 return StaticCtorSection;
353 std::string Name = std::string(".init_array.") + utostr(Priority);
354 return getContext().getELFSection(Name, ELF::SHT_INIT_ARRAY,
355 ELF::SHF_ALLOC | ELF::SHF_WRITE,
356 SectionKind::getDataRel());
358 std::string Name = std::string(".ctors.") + utostr(65535 - Priority);
359 return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
360 ELF::SHF_ALLOC |ELF::SHF_WRITE,
361 SectionKind::getDataRel());
366 TargetLoweringObjectFileELF::getStaticDtorSection(unsigned Priority) const {
367 // The default scheme is .ctor / .dtor, so we have to invert the priority
369 if (Priority == 65535)
370 return StaticDtorSection;
373 std::string Name = std::string(".fini_array.") + utostr(Priority);
374 return getContext().getELFSection(Name, ELF::SHT_FINI_ARRAY,
375 ELF::SHF_ALLOC | ELF::SHF_WRITE,
376 SectionKind::getDataRel());
378 std::string Name = std::string(".dtors.") + utostr(65535 - Priority);
379 return getContext().getELFSection(Name, ELF::SHT_PROGBITS,
380 ELF::SHF_ALLOC |ELF::SHF_WRITE,
381 SectionKind::getDataRel());
386 TargetLoweringObjectFileELF::InitializeELF(bool UseInitArray_) {
387 UseInitArray = UseInitArray_;
392 getContext().getELFSection(".init_array", ELF::SHT_INIT_ARRAY,
395 SectionKind::getDataRel());
397 getContext().getELFSection(".fini_array", ELF::SHT_FINI_ARRAY,
400 SectionKind::getDataRel());
403 //===----------------------------------------------------------------------===//
405 //===----------------------------------------------------------------------===//
407 /// getDepLibFromLinkerOpt - Extract the dependent library name from a linker
408 /// option string. Returns StringRef() if the option does not specify a library.
409 StringRef TargetLoweringObjectFileMachO::
410 getDepLibFromLinkerOpt(StringRef LinkerOption) const {
411 const char *LibCmd = "-l";
412 if (LinkerOption.startswith(LibCmd))
413 return LinkerOption.substr(strlen(LibCmd));
417 /// emitModuleFlags - Perform code emission for module flags.
418 void TargetLoweringObjectFileMachO::
419 emitModuleFlags(MCStreamer &Streamer,
420 ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
421 Mangler *Mang, const TargetMachine &TM) const {
422 unsigned VersionVal = 0;
423 unsigned ImageInfoFlags = 0;
424 MDNode *LinkerOptions = 0;
425 StringRef SectionVal;
427 for (ArrayRef<Module::ModuleFlagEntry>::iterator
428 i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
429 const Module::ModuleFlagEntry &MFE = *i;
431 // Ignore flags with 'Require' behavior.
432 if (MFE.Behavior == Module::Require)
435 StringRef Key = MFE.Key->getString();
436 Value *Val = MFE.Val;
438 if (Key == "Objective-C Image Info Version") {
439 VersionVal = cast<ConstantInt>(Val)->getZExtValue();
440 } else if (Key == "Objective-C Garbage Collection" ||
441 Key == "Objective-C GC Only" ||
442 Key == "Objective-C Is Simulated") {
443 ImageInfoFlags |= cast<ConstantInt>(Val)->getZExtValue();
444 } else if (Key == "Objective-C Image Info Section") {
445 SectionVal = cast<MDString>(Val)->getString();
446 } else if (Key == "Linker Options") {
447 LinkerOptions = cast<MDNode>(Val);
451 // Emit the linker options if present.
453 for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
454 MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
455 SmallVector<std::string, 4> StrOptions;
457 // Convert to strings.
458 for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
459 MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
460 StrOptions.push_back(MDOption->getString());
463 Streamer.EmitLinkerOptions(StrOptions);
467 // The section is mandatory. If we don't have it, then we don't have GC info.
468 if (SectionVal.empty()) return;
470 StringRef Segment, Section;
471 unsigned TAA = 0, StubSize = 0;
473 std::string ErrorCode =
474 MCSectionMachO::ParseSectionSpecifier(SectionVal, Segment, Section,
475 TAA, TAAParsed, StubSize);
476 if (!ErrorCode.empty())
477 // If invalid, report the error with report_fatal_error.
478 report_fatal_error("Invalid section specifier '" + Section + "': " +
482 const MCSectionMachO *S =
483 getContext().getMachOSection(Segment, Section, TAA, StubSize,
484 SectionKind::getDataNoRel());
485 Streamer.SwitchSection(S);
486 Streamer.EmitLabel(getContext().
487 GetOrCreateSymbol(StringRef("L_OBJC_IMAGE_INFO")));
488 Streamer.EmitIntValue(VersionVal, 4);
489 Streamer.EmitIntValue(ImageInfoFlags, 4);
490 Streamer.AddBlankLine();
493 const MCSection *TargetLoweringObjectFileMachO::
494 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
495 Mangler *Mang, const TargetMachine &TM) const {
496 // Parse the section specifier and create it if valid.
497 StringRef Segment, Section;
498 unsigned TAA = 0, StubSize = 0;
500 std::string ErrorCode =
501 MCSectionMachO::ParseSectionSpecifier(GV->getSection(), Segment, Section,
502 TAA, TAAParsed, StubSize);
503 if (!ErrorCode.empty()) {
504 // If invalid, report the error with report_fatal_error.
505 report_fatal_error("Global variable '" + GV->getName() +
506 "' has an invalid section specifier '" +
507 GV->getSection() + "': " + ErrorCode + ".");
511 const MCSectionMachO *S =
512 getContext().getMachOSection(Segment, Section, TAA, StubSize, Kind);
514 // If TAA wasn't set by ParseSectionSpecifier() above,
515 // use the value returned by getMachOSection() as a default.
517 TAA = S->getTypeAndAttributes();
519 // Okay, now that we got the section, verify that the TAA & StubSize agree.
520 // If the user declared multiple globals with different section flags, we need
521 // to reject it here.
522 if (S->getTypeAndAttributes() != TAA || S->getStubSize() != StubSize) {
523 // If invalid, report the error with report_fatal_error.
524 report_fatal_error("Global variable '" + GV->getName() +
525 "' section type or attributes does not match previous"
526 " section specifier");
532 const MCSection *TargetLoweringObjectFileMachO::
533 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
534 Mangler *Mang, TargetMachine &TM) const {
536 // Handle thread local data.
537 if (Kind.isThreadBSS()) return TLSBSSSection;
538 if (Kind.isThreadData()) return TLSDataSection;
541 return GV->isWeakForLinker() ? TextCoalSection : TextSection;
543 // If this is weak/linkonce, put this in a coalescable section, either in text
544 // or data depending on if it is writable.
545 if (GV->isWeakForLinker()) {
546 if (Kind.isReadOnly())
547 return ConstTextCoalSection;
548 return DataCoalSection;
551 // FIXME: Alignment check should be handled by section classifier.
552 if (Kind.isMergeable1ByteCString() &&
553 TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV)) < 32)
554 return CStringSection;
556 // Do not put 16-bit arrays in the UString section if they have an
557 // externally visible label, this runs into issues with certain linker
559 if (Kind.isMergeable2ByteCString() && !GV->hasExternalLinkage() &&
560 TM.getDataLayout()->getPreferredAlignment(cast<GlobalVariable>(GV)) < 32)
561 return UStringSection;
563 if (Kind.isMergeableConst()) {
564 if (Kind.isMergeableConst4())
565 return FourByteConstantSection;
566 if (Kind.isMergeableConst8())
567 return EightByteConstantSection;
568 if (Kind.isMergeableConst16() && SixteenByteConstantSection)
569 return SixteenByteConstantSection;
572 // Otherwise, if it is readonly, but not something we can specially optimize,
573 // just drop it in .const.
574 if (Kind.isReadOnly())
575 return ReadOnlySection;
577 // If this is marked const, put it into a const section. But if the dynamic
578 // linker needs to write to it, put it in the data segment.
579 if (Kind.isReadOnlyWithRel())
580 return ConstDataSection;
582 // Put zero initialized globals with strong external linkage in the
583 // DATA, __common section with the .zerofill directive.
584 if (Kind.isBSSExtern())
585 return DataCommonSection;
587 // Put zero initialized globals with local linkage in __DATA,__bss directive
588 // with the .zerofill directive (aka .lcomm).
589 if (Kind.isBSSLocal())
590 return DataBSSSection;
592 // Otherwise, just drop the variable in the normal data section.
597 TargetLoweringObjectFileMachO::getSectionForConstant(SectionKind Kind) const {
598 // If this constant requires a relocation, we have to put it in the data
599 // segment, not in the text segment.
600 if (Kind.isDataRel() || Kind.isReadOnlyWithRel())
601 return ConstDataSection;
603 if (Kind.isMergeableConst4())
604 return FourByteConstantSection;
605 if (Kind.isMergeableConst8())
606 return EightByteConstantSection;
607 if (Kind.isMergeableConst16() && SixteenByteConstantSection)
608 return SixteenByteConstantSection;
609 return ReadOnlySection; // .const
612 /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively decide
613 /// not to emit the UsedDirective for some symbols in llvm.used.
614 // FIXME: REMOVE this (rdar://7071300)
615 bool TargetLoweringObjectFileMachO::
616 shouldEmitUsedDirectiveFor(const GlobalValue *GV, Mangler *Mang) const {
617 /// On Darwin, internally linked data beginning with "L" or "l" does not have
618 /// the directive emitted (this occurs in ObjC metadata).
619 if (!GV) return false;
621 // Check whether the mangled name has the "Private" or "LinkerPrivate" prefix.
622 if (GV->hasLocalLinkage() && !isa<Function>(GV)) {
623 // FIXME: ObjC metadata is currently emitted as internal symbols that have
624 // \1L and \0l prefixes on them. Fix them to be Private/LinkerPrivate and
625 // this horrible hack can go away.
626 MCSymbol *Sym = getSymbol(*Mang, GV);
627 if (Sym->getName()[0] == 'L' || Sym->getName()[0] == 'l')
634 const MCExpr *TargetLoweringObjectFileMachO::
635 getTTypeGlobalReference(const GlobalValue *GV, Mangler *Mang,
636 MachineModuleInfo *MMI, unsigned Encoding,
637 MCStreamer &Streamer) const {
638 // The mach-o version of this method defaults to returning a stub reference.
640 if (Encoding & DW_EH_PE_indirect) {
641 MachineModuleInfoMachO &MachOMMI =
642 MMI->getObjFileInfo<MachineModuleInfoMachO>();
644 MCSymbol *SSym = getSymbolWithGlobalValueBase(*Mang, GV, "$non_lazy_ptr");
646 // Add information about the stub reference to MachOMMI so that the stub
647 // gets emitted by the asmprinter.
648 MachineModuleInfoImpl::StubValueTy &StubSym =
649 GV->hasHiddenVisibility() ? MachOMMI.getHiddenGVStubEntry(SSym) :
650 MachOMMI.getGVStubEntry(SSym);
651 if (StubSym.getPointer() == 0) {
652 MCSymbol *Sym = getSymbol(*Mang, GV);
653 StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
656 return TargetLoweringObjectFile::
657 getTTypeReference(MCSymbolRefExpr::Create(SSym, getContext()),
658 Encoding & ~dwarf::DW_EH_PE_indirect, Streamer);
661 return TargetLoweringObjectFile::
662 getTTypeGlobalReference(GV, Mang, MMI, Encoding, Streamer);
665 MCSymbol *TargetLoweringObjectFileMachO::
666 getCFIPersonalitySymbol(const GlobalValue *GV, Mangler *Mang,
667 MachineModuleInfo *MMI) const {
668 // The mach-o version of this method defaults to returning a stub reference.
669 MachineModuleInfoMachO &MachOMMI =
670 MMI->getObjFileInfo<MachineModuleInfoMachO>();
672 MCSymbol *SSym = getSymbolWithGlobalValueBase(*Mang, GV, "$non_lazy_ptr");
674 // Add information about the stub reference to MachOMMI so that the stub
675 // gets emitted by the asmprinter.
676 MachineModuleInfoImpl::StubValueTy &StubSym = MachOMMI.getGVStubEntry(SSym);
677 if (StubSym.getPointer() == 0) {
678 MCSymbol *Sym = getSymbol(*Mang, GV);
679 StubSym = MachineModuleInfoImpl::StubValueTy(Sym, !GV->hasLocalLinkage());
685 //===----------------------------------------------------------------------===//
687 //===----------------------------------------------------------------------===//
690 getCOFFSectionFlags(SectionKind K) {
695 COFF::IMAGE_SCN_MEM_DISCARDABLE;
698 COFF::IMAGE_SCN_MEM_EXECUTE |
699 COFF::IMAGE_SCN_MEM_READ |
700 COFF::IMAGE_SCN_CNT_CODE;
703 COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
704 COFF::IMAGE_SCN_MEM_READ |
705 COFF::IMAGE_SCN_MEM_WRITE;
706 else if (K.isThreadLocal())
708 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
709 COFF::IMAGE_SCN_MEM_READ |
710 COFF::IMAGE_SCN_MEM_WRITE;
711 else if (K.isReadOnly())
713 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
714 COFF::IMAGE_SCN_MEM_READ;
715 else if (K.isWriteable())
717 COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
718 COFF::IMAGE_SCN_MEM_READ |
719 COFF::IMAGE_SCN_MEM_WRITE;
724 const MCSection *TargetLoweringObjectFileCOFF::
725 getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
726 Mangler *Mang, const TargetMachine &TM) const {
728 unsigned Characteristics = getCOFFSectionFlags(Kind);
729 StringRef Name = GV->getSection();
730 StringRef COMDATSymName = "";
731 if (GV->isWeakForLinker()) {
732 Selection = COFF::IMAGE_COMDAT_SELECT_ANY;
733 Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
734 MCSymbol *Sym = getSymbol(*Mang, GV);
735 COMDATSymName = Sym->getName();
737 return getContext().getCOFFSection(Name,
744 static const char *getCOFFSectionNameForUniqueGlobal(SectionKind Kind) {
749 if (Kind.isThreadLocal())
751 if (Kind.isWriteable())
757 const MCSection *TargetLoweringObjectFileCOFF::
758 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
759 Mangler *Mang, TargetMachine &TM) const {
761 // If this global is linkonce/weak and the target handles this by emitting it
762 // into a 'uniqued' section name, create and return the section now.
763 if (GV->isWeakForLinker()) {
764 const char *Name = getCOFFSectionNameForUniqueGlobal(Kind);
765 unsigned Characteristics = getCOFFSectionFlags(Kind);
767 Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT;
768 MCSymbol *Sym = getSymbol(*Mang, GV);
769 return getContext().getCOFFSection(Name, Characteristics,
770 Kind, Sym->getName(),
771 COFF::IMAGE_COMDAT_SELECT_ANY);
777 if (Kind.isThreadLocal())
778 return TLSDataSection;
780 if (Kind.isReadOnly())
781 return ReadOnlySection;
789 StringRef TargetLoweringObjectFileCOFF::
790 getDepLibFromLinkerOpt(StringRef LinkerOption) const {
791 const char *LibCmd = "/DEFAULTLIB:";
792 if (LinkerOption.startswith(LibCmd))
793 return LinkerOption.substr(strlen(LibCmd));
797 void TargetLoweringObjectFileCOFF::
798 emitModuleFlags(MCStreamer &Streamer,
799 ArrayRef<Module::ModuleFlagEntry> ModuleFlags,
800 Mangler *Mang, const TargetMachine &TM) const {
801 MDNode *LinkerOptions = 0;
803 // Look for the "Linker Options" flag, since it's the only one we support.
804 for (ArrayRef<Module::ModuleFlagEntry>::iterator
805 i = ModuleFlags.begin(), e = ModuleFlags.end(); i != e; ++i) {
806 const Module::ModuleFlagEntry &MFE = *i;
807 StringRef Key = MFE.Key->getString();
808 Value *Val = MFE.Val;
809 if (Key == "Linker Options") {
810 LinkerOptions = cast<MDNode>(Val);
817 // Emit the linker options to the linker .drectve section. According to the
818 // spec, this section is a space-separated string containing flags for linker.
819 const MCSection *Sec = getDrectveSection();
820 Streamer.SwitchSection(Sec);
821 for (unsigned i = 0, e = LinkerOptions->getNumOperands(); i != e; ++i) {
822 MDNode *MDOptions = cast<MDNode>(LinkerOptions->getOperand(i));
823 for (unsigned ii = 0, ie = MDOptions->getNumOperands(); ii != ie; ++ii) {
824 MDString *MDOption = cast<MDString>(MDOptions->getOperand(ii));
825 StringRef Op = MDOption->getString();
826 // Lead with a space for consistency with our dllexport implementation.
827 std::string Escaped(" ");
828 if (Op.find(" ") != StringRef::npos) {
829 // The PE-COFF spec says args with spaces must be quoted. It doesn't say
830 // how to escape quotes, but it probably uses this algorithm:
831 // http://msdn.microsoft.com/en-us/library/17w5ykft(v=vs.85).aspx
832 // FIXME: Reuse escaping code from Support/Windows/Program.inc
833 Escaped.push_back('\"');
835 Escaped.push_back('\"');
839 Streamer.EmitBytes(Escaped);