+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;
+}
+
+
+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())
+ return SectionKind::ROData;
+ else {
+ // Check, if initializer is a null-terminated string
+ if (isConstantString(C))
+ return SectionKind::RODataMergeStr;
+ else
+ return SectionKind::RODataMergeConst;
+ }
+ }
+
+ // Variable is not constant or thread-local - emit to generic 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::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:
+ assert(0 && "Unexpected section kind!");
+ }
+
+ if (GV->mayBeOverridden())
+ 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->mayBeOverridden()) {
+ 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::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:
+ assert(0 && "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;
+}
+
+unsigned TargetAsmInfo::getULEB128Size(unsigned Value) {
+ unsigned Size = 0;
+ do {
+ Value >>= 7;
+ Size += sizeof(int8_t);
+ } while (Value);
+ return Size;
+}
+
+unsigned TargetAsmInfo::getSLEB128Size(int Value) {
+ unsigned Size = 0;
+ int Sign = Value >> (8 * sizeof(Value) - 1);
+ bool IsMore;
+
+ do {
+ unsigned Byte = Value & 0x7f;
+ Value >>= 7;
+ IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
+ Size += sizeof(int8_t);
+ } while (IsMore);
+ return Size;
+}