-/// Measure the specified inline asm to determine an approximation of its
-/// length.
-/// Comments (which run till the next SeparatorChar or newline) do not
-/// count as an instruction.
-/// Any other non-whitespace text is considered an instruction, with
-/// multiple instructions separated by SeparatorChar or newlines.
-/// Variable-length instructions are not handled here; this function
-/// may be overloaded in the target code to do that.
-unsigned TargetAsmInfo::getInlineAsmLength(const char *Str) const {
- // Count the number of instructions in the asm.
- bool atInsnStart = true;
- unsigned Length = 0;
- for (; *Str; ++Str) {
- if (*Str == '\n' || *Str == SeparatorChar)
- atInsnStart = true;
- if (atInsnStart && !isspace(*Str)) {
- Length += MaxInstLength;
- atInsnStart = false;
- }
- if (atInsnStart && strncmp(Str, CommentString, strlen(CommentString))==0)
- atInsnStart = false;
- }
-
- return Length;
-}
-
-unsigned TargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
- bool Global) const {
- return dwarf::DW_EH_PE_absptr;
-}
-
-static bool isSuitableForBSS(const GlobalVariable *GV) {
- if (!GV->hasInitializer())
- return true;
-
- // Leave constant zeros in readonly constant sections, so they can be shared
- Constant *C = GV->getInitializer();
- return (C->isNullValue() && !GV->isConstant() && !NoZerosInBSS);
-}
-
-static bool isConstantString(const Constant *C) {
- // First check: is we have constant array of i8 terminated with zero
- const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
- // Check, if initializer is a null-terminated string
- if (CVA && CVA->isCString())
- return true;
-
- // Another possibility: [1 x i8] zeroinitializer
- if (isa<ConstantAggregateZero>(C)) {
- if (const ArrayType *Ty = dyn_cast<ArrayType>(C->getType())) {
- return (Ty->getElementType() == Type::Int8Ty &&
- Ty->getNumElements() == 1);
- }
- }
-
- return false;
-}
-
-unsigned TargetAsmInfo::RelocBehaviour() const {
- // By default - all relocations in PIC mode would force symbol to be
- // placed in r/w section.
- return (TM.getRelocationModel() != Reloc::Static ?
- Reloc::LocalOrGlobal : Reloc::None);
-}
-
-SectionKind::Kind
-TargetAsmInfo::SectionKindForGlobal(const GlobalValue *GV) const {
- // Early exit - functions should be always in text sections.
- if (isa<Function>(GV))
- return SectionKind::Text;
-
- const GlobalVariable* GVar = dyn_cast<GlobalVariable>(GV);
- bool isThreadLocal = GVar->isThreadLocal();
- assert(GVar && "Invalid global value for section selection");
-
- if (isSuitableForBSS(GVar)) {
- // Variable can be easily put to BSS section.
- return (isThreadLocal ? SectionKind::ThreadBSS : SectionKind::BSS);
- } else if (GVar->isConstant() && !isThreadLocal) {
- // Now we know, that varible has initializer and it is constant. We need to
- // check its initializer to decide, which section to output it into. Also
- // note, there is no thread-local r/o section.
- Constant *C = GVar->getInitializer();
- if (C->ContainsRelocations(Reloc::LocalOrGlobal)) {
- // Decide, whether it is still possible to put symbol into r/o section.
- unsigned Reloc = RelocBehaviour();
-
- // We already did a query for 'all' relocs, thus - early exits.
- if (Reloc == Reloc::LocalOrGlobal)
- return SectionKind::Data;
- else if (Reloc == Reloc::None)
- return SectionKind::ROData;
- else {
- // Ok, target wants something funny. Honour it.
- return (C->ContainsRelocations(Reloc) ?
- SectionKind::Data : SectionKind::ROData);
- }
- } else {
- // Check, if initializer is a null-terminated string
- if (isConstantString(C))
- return SectionKind::RODataMergeStr;
- else
- return SectionKind::RODataMergeConst;
- }
- }
-
- // Variable either is not constant or thread-local - output to data section.
- return (isThreadLocal ? SectionKind::ThreadData : SectionKind::Data);
-}
-
-unsigned
-TargetAsmInfo::SectionFlagsForGlobal(const GlobalValue *GV,
- const char* Name) const {
- unsigned Flags = SectionFlags::None;
-
- // Decode flags from global itself.
- if (GV) {
- SectionKind::Kind Kind = SectionKindForGlobal(GV);
- switch (Kind) {
- case SectionKind::Text:
- Flags |= SectionFlags::Code;
- break;
- case SectionKind::ThreadData:
- case SectionKind::ThreadBSS:
- Flags |= SectionFlags::TLS;
- // FALLS THROUGH
- case SectionKind::Data:
- case SectionKind::DataRel:
- case SectionKind::DataRelLocal:
- case SectionKind::DataRelRO:
- case SectionKind::DataRelROLocal:
- case SectionKind::BSS:
- Flags |= SectionFlags::Writeable;
- break;
- case SectionKind::ROData:
- case SectionKind::RODataMergeStr:
- case SectionKind::RODataMergeConst:
- // No additional flags here
- break;
- case SectionKind::SmallData:
- case SectionKind::SmallBSS:
- Flags |= SectionFlags::Writeable;
- // FALLS THROUGH
- case SectionKind::SmallROData:
- Flags |= SectionFlags::Small;
- break;
- default:
- llvm_unreachable("Unexpected section kind!");
- }
-
- if (GV->isWeakForLinker())
- Flags |= SectionFlags::Linkonce;
- }
-
- // Add flags from sections, if any.
- if (Name && *Name) {
- Flags |= SectionFlags::Named;
-
- // Some lame default implementation based on some magic section names.
- if (strncmp(Name, ".gnu.linkonce.b.", 16) == 0 ||
- strncmp(Name, ".llvm.linkonce.b.", 17) == 0 ||
- strncmp(Name, ".gnu.linkonce.sb.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.sb.", 18) == 0)
- Flags |= SectionFlags::BSS;
- else if (strcmp(Name, ".tdata") == 0 ||
- strncmp(Name, ".tdata.", 7) == 0 ||
- strncmp(Name, ".gnu.linkonce.td.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.td.", 18) == 0)
- Flags |= SectionFlags::TLS;
- else if (strcmp(Name, ".tbss") == 0 ||
- strncmp(Name, ".tbss.", 6) == 0 ||
- strncmp(Name, ".gnu.linkonce.tb.", 17) == 0 ||
- strncmp(Name, ".llvm.linkonce.tb.", 18) == 0)
- Flags |= SectionFlags::BSS | SectionFlags::TLS;
- }
-
- return Flags;
-}
-
-const Section*
-TargetAsmInfo::SectionForGlobal(const GlobalValue *GV) const {
- const Section* S;
- // Select section name
- if (GV->hasSection()) {
- // Honour section already set, if any
- unsigned Flags = SectionFlagsForGlobal(GV,
- GV->getSection().c_str());
- S = getNamedSection(GV->getSection().c_str(), Flags);
- } else {
- // Use default section depending on the 'type' of global
- S = SelectSectionForGlobal(GV);
- }
-
- return S;
-}
-
-// Lame default implementation. Calculate the section name for global.
-const Section*
-TargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV) const {
- SectionKind::Kind Kind = SectionKindForGlobal(GV);
-
- if (GV->isWeakForLinker()) {
- std::string Name = UniqueSectionForGlobal(GV, Kind);
- unsigned Flags = SectionFlagsForGlobal(GV, Name.c_str());
- return getNamedSection(Name.c_str(), Flags);
- } else {
- if (Kind == SectionKind::Text)
- return getTextSection();
- else if (isBSS(Kind) && getBSSSection_())
- return getBSSSection_();
- else if (getReadOnlySection() && SectionKind::isReadOnly(Kind))
- return getReadOnlySection();
- }
-
- return getDataSection();
-}
-
-// Lame default implementation. Calculate the section name for machine const.
-const Section*
-TargetAsmInfo::SelectSectionForMachineConst(const Type *Ty) const {
- // FIXME: Support data.rel stuff someday
- return getDataSection();
-}
-
-std::string
-TargetAsmInfo::UniqueSectionForGlobal(const GlobalValue* GV,
- SectionKind::Kind Kind) const {
- switch (Kind) {
- case SectionKind::Text:
- return ".gnu.linkonce.t." + GV->getName();
- case SectionKind::Data:
- return ".gnu.linkonce.d." + GV->getName();
- case SectionKind::DataRel:
- return ".gnu.linkonce.d.rel" + GV->getName();
- case SectionKind::DataRelLocal:
- return ".gnu.linkonce.d.rel.local" + GV->getName();
- case SectionKind::DataRelRO:
- return ".gnu.linkonce.d.rel.ro" + GV->getName();
- case SectionKind::DataRelROLocal:
- return ".gnu.linkonce.d.rel.ro.local" + GV->getName();
- case SectionKind::SmallData:
- return ".gnu.linkonce.s." + GV->getName();
- case SectionKind::BSS:
- return ".gnu.linkonce.b." + GV->getName();
- case SectionKind::SmallBSS:
- return ".gnu.linkonce.sb." + GV->getName();
- case SectionKind::ROData:
- case SectionKind::RODataMergeConst:
- case SectionKind::RODataMergeStr:
- return ".gnu.linkonce.r." + GV->getName();
- case SectionKind::SmallROData:
- return ".gnu.linkonce.s2." + GV->getName();
- case SectionKind::ThreadData:
- return ".gnu.linkonce.td." + GV->getName();
- case SectionKind::ThreadBSS:
- return ".gnu.linkonce.tb." + GV->getName();
- default:
- llvm_unreachable("Unknown section kind");
- }
- return NULL;
-}
-
-const Section*
-TargetAsmInfo::getNamedSection(const char *Name, unsigned Flags,
- bool Override) const {
- Section& S = Sections[Name];
-
- // This is newly-created section, set it up properly.
- if (S.Flags == SectionFlags::Invalid || Override) {
- S.Flags = Flags | SectionFlags::Named;
- S.Name = Name;
- }
-
- return &S;
-}
-
-const Section*
-TargetAsmInfo::getUnnamedSection(const char *Directive, unsigned Flags,
- bool Override) const {
- Section& S = Sections[Directive];
-
- // This is newly-created section, set it up properly.
- if (S.Flags == SectionFlags::Invalid || Override) {
- S.Flags = Flags & ~SectionFlags::Named;
- S.Name = Directive;
- }
-
- return &S;
-}
-
-const std::string&
-TargetAsmInfo::getSectionFlags(unsigned Flags) const {
- SectionFlags::FlagsStringsMapType::iterator I = FlagsStrings.find(Flags);
-
- // We didn't print these flags yet, print and save them to map. This reduces
- // amount of heap trashing due to std::string construction / concatenation.
- if (I == FlagsStrings.end())
- I = FlagsStrings.insert(std::make_pair(Flags,
- printSectionFlags(Flags))).first;
-
- return I->second;
-}