//
//===----------------------------------------------------------------------===//
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Function.h"
+#include "llvm/Module.h"
+#include "llvm/Type.h"
#include "llvm/Target/TargetAsmInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ErrorHandling.h"
#include <cctype>
#include <cstring>
-
using namespace llvm;
-TargetAsmInfo::TargetAsmInfo() :
- TextSection("\t.text"),
- DataSection("\t.data"),
- BSSSection("\t.bss"),
- TLSDataSection("\t.section .tdata,\"awT\",@progbits"),
- TLSBSSSection("\t.section .tbss,\"awT\",@nobits"),
- ZeroFillDirective(0),
- NeedsSet(false),
- MaxInstLength(4),
- PCSymbol("$"),
- SeparatorChar(';'),
- CommentString("#"),
- GlobalPrefix(""),
- PrivateGlobalPrefix("."),
- JumpTableSpecialLabelPrefix(0),
- GlobalVarAddrPrefix(""),
- GlobalVarAddrSuffix(""),
- FunctionAddrPrefix(""),
- FunctionAddrSuffix(""),
- PersonalityPrefix(""),
- PersonalitySuffix(""),
- NeedsIndirectEncoding(false),
- InlineAsmStart("#APP"),
- InlineAsmEnd("#NO_APP"),
- AssemblerDialect(0),
- ZeroDirective("\t.zero\t"),
- ZeroDirectiveSuffix(0),
- AsciiDirective("\t.ascii\t"),
- AscizDirective("\t.asciz\t"),
- Data8bitsDirective("\t.byte\t"),
- Data16bitsDirective("\t.short\t"),
- Data32bitsDirective("\t.long\t"),
- Data64bitsDirective("\t.quad\t"),
- AlignDirective("\t.align\t"),
- AlignmentIsInBytes(true),
- SwitchToSectionDirective("\t.section\t"),
- TextSectionStartSuffix(""),
- DataSectionStartSuffix(""),
- SectionEndDirectiveSuffix(0),
- ConstantPoolSection("\t.section .rodata"),
- JumpTableDataSection("\t.section .rodata"),
- JumpTableDirective(0),
- CStringSection(0),
- StaticCtorsSection("\t.section .ctors,\"aw\",@progbits"),
- StaticDtorsSection("\t.section .dtors,\"aw\",@progbits"),
- FourByteConstantSection(0),
- EightByteConstantSection(0),
- SixteenByteConstantSection(0),
- ReadOnlySection(0),
- GlobalDirective("\t.globl\t"),
- SetDirective(0),
- LCOMMDirective(0),
- COMMDirective("\t.comm\t"),
- COMMDirectiveTakesAlignment(true),
- HasDotTypeDotSizeDirective(true),
- UsedDirective(0),
- WeakRefDirective(0),
- WeakDefDirective(0),
- HiddenDirective("\t.hidden\t"),
- ProtectedDirective("\t.protected\t"),
- AbsoluteDebugSectionOffsets(false),
- AbsoluteEHSectionOffsets(false),
- HasLEB128(false),
- HasDotLocAndDotFile(false),
- SupportsDebugInformation(false),
- SupportsExceptionHandling(false),
- DwarfRequiresFrameSection(true),
- GlobalEHDirective(0),
- SupportsWeakOmittedEHFrame(true),
- ShortenEHDataOn64Bit(false),
- DwarfSectionOffsetDirective(0),
- DwarfAbbrevSection(".debug_abbrev"),
- DwarfInfoSection(".debug_info"),
- DwarfLineSection(".debug_line"),
- DwarfFrameSection(".debug_frame"),
- DwarfPubNamesSection(".debug_pubnames"),
- DwarfPubTypesSection(".debug_pubtypes"),
- DwarfStrSection(".debug_str"),
- DwarfLocSection(".debug_loc"),
- DwarfARangesSection(".debug_aranges"),
- DwarfRangesSection(".debug_ranges"),
- DwarfMacInfoSection(".debug_macinfo"),
- DwarfEHFrameSection(".eh_frame"),
- DwarfExceptionSection(".gcc_except_table"),
- AsmTransCBE(0) {
+TargetAsmInfo::TargetAsmInfo(const TargetMachine &tm) : TM(tm) {
+ BSSSection = "\t.bss";
+ BSSSection_ = 0;
+ ReadOnlySection = 0;
+ TLSDataSection = 0;
+ TLSBSSSection = 0;
+ ZeroFillDirective = 0;
+ NonexecutableStackDirective = 0;
+ NeedsSet = false;
+ MaxInstLength = 4;
+ PCSymbol = "$";
+ SeparatorChar = ';';
+ CommentColumn = 60;
+ CommentString = "#";
+ FirstOperandColumn = 0;
+ MaxOperandLength = 0;
+ GlobalPrefix = "";
+ PrivateGlobalPrefix = ".";
+ LinkerPrivateGlobalPrefix = "";
+ JumpTableSpecialLabelPrefix = 0;
+ GlobalVarAddrPrefix = "";
+ GlobalVarAddrSuffix = "";
+ FunctionAddrPrefix = "";
+ FunctionAddrSuffix = "";
+ PersonalityPrefix = "";
+ PersonalitySuffix = "";
+ NeedsIndirectEncoding = false;
+ InlineAsmStart = "#APP";
+ InlineAsmEnd = "#NO_APP";
+ AssemblerDialect = 0;
+ AllowQuotesInName = false;
+ ZeroDirective = "\t.zero\t";
+ ZeroDirectiveSuffix = 0;
+ AsciiDirective = "\t.ascii\t";
+ AscizDirective = "\t.asciz\t";
+ Data8bitsDirective = "\t.byte\t";
+ Data16bitsDirective = "\t.short\t";
+ Data32bitsDirective = "\t.long\t";
+ Data64bitsDirective = "\t.quad\t";
+ AlignDirective = "\t.align\t";
+ AlignmentIsInBytes = true;
+ TextAlignFillValue = 0;
+ SwitchToSectionDirective = "\t.section\t";
+ TextSectionStartSuffix = "";
+ DataSectionStartSuffix = "";
+ SectionEndDirectiveSuffix = 0;
+ ConstantPoolSection = "\t.section .rodata";
+ JumpTableDataSection = "\t.section .rodata";
+ JumpTableDirective = 0;
+ CStringSection = 0;
+ CStringSection_ = 0;
+ // FIXME: Flags are ELFish - replace with normal section stuff.
+ StaticCtorsSection = "\t.section .ctors,\"aw\",@progbits";
+ StaticDtorsSection = "\t.section .dtors,\"aw\",@progbits";
+ GlobalDirective = "\t.globl\t";
+ SetDirective = 0;
+ LCOMMDirective = 0;
+ COMMDirective = "\t.comm\t";
+ COMMDirectiveTakesAlignment = true;
+ HasDotTypeDotSizeDirective = true;
+ HasSingleParameterDotFile = true;
+ UsedDirective = 0;
+ WeakRefDirective = 0;
+ WeakDefDirective = 0;
+ // FIXME: These are ELFish - move to ELFTAI.
+ HiddenDirective = "\t.hidden\t";
+ ProtectedDirective = "\t.protected\t";
+ AbsoluteDebugSectionOffsets = false;
+ AbsoluteEHSectionOffsets = false;
+ HasLEB128 = false;
+ HasDotLocAndDotFile = false;
+ SupportsDebugInformation = false;
+ SupportsExceptionHandling = false;
+ DwarfRequiresFrameSection = true;
+ DwarfUsesInlineInfoSection = false;
+ Is_EHSymbolPrivate = true;
+ GlobalEHDirective = 0;
+ SupportsWeakOmittedEHFrame = true;
+ DwarfSectionOffsetDirective = 0;
+ DwarfAbbrevSection = ".debug_abbrev";
+ DwarfInfoSection = ".debug_info";
+ DwarfLineSection = ".debug_line";
+ DwarfFrameSection = ".debug_frame";
+ DwarfPubNamesSection = ".debug_pubnames";
+ DwarfPubTypesSection = ".debug_pubtypes";
+ DwarfDebugInlineSection = ".debug_inlined";
+ DwarfStrSection = ".debug_str";
+ DwarfLocSection = ".debug_loc";
+ DwarfARangesSection = ".debug_aranges";
+ DwarfRangesSection = ".debug_ranges";
+ DwarfMacroInfoSection = ".debug_macinfo";
+ DwarfEHFrameSection = ".eh_frame";
+ DwarfExceptionSection = ".gcc_except_table";
+ AsmTransCBE = 0;
+ TextSection = getUnnamedSection("\t.text", SectionFlags::Code);
+ DataSection = getUnnamedSection("\t.data", SectionFlags::Writeable);
}
TargetAsmInfo::~TargetAsmInfo() {
return Length;
}
-unsigned TargetAsmInfo::PreferredEHDataFormat(unsigned Reason,
+unsigned TargetAsmInfo::PreferredEHDataFormat(DwarfEncoding::Target Reason,
bool Global) const {
return dwarf::DW_EH_PE_absptr;
}
+static bool isSuitableForBSS(const GlobalVariable *GV) {
+ // 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;
+}
+
+static unsigned SectionFlagsForGlobal(const GlobalValue *GV,
+ SectionKind::Kind Kind) {
+ unsigned Flags = SectionFlags::None;
+
+ // Decode flags from global itself.
+ 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;
+ default:
+ llvm_unreachable("Unexpected section kind!");
+ }
+
+ if (GV->isWeakForLinker())
+ Flags |= SectionFlags::Linkonce;
+
+ return Flags;
+}
+
+static SectionKind::Kind SectionKindForGlobal(const GlobalValue *GV,
+ Reloc::Model ReloModel) {
+ // Early exit - functions should be always in text sections.
+ const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
+ if (GVar == 0)
+ return SectionKind::Text;
+
+ bool isThreadLocal = GVar->isThreadLocal();
+
+ // Variable can be easily put to BSS section.
+ if (isSuitableForBSS(GVar))
+ return isThreadLocal ? SectionKind::ThreadBSS : SectionKind::BSS;
+
+ // If this is thread-local, put it in the general "thread_data" section.
+ if (isThreadLocal)
+ return SectionKind::ThreadData;
+
+ Constant *C = GVar->getInitializer();
+
+ // If the global is marked constant, we can put it into a mergable section,
+ // a mergable string section, or general .data if it contains relocations.
+ if (GVar->isConstant()) {
+ // If the initializer for the global contains something that requires a
+ // relocation, then we may have to drop this into a wriable data section
+ // even though it is marked const.
+ switch (C->getRelocationInfo()) {
+ default: llvm_unreachable("unknown relocation info kind");
+ case Constant::NoRelocation:
+ // If initializer is a null-terminated string, put it in a "cstring"
+ // section if the target has it.
+ if (isConstantString(C))
+ return SectionKind::RODataMergeStr;
+
+ // Otherwise, just drop it into a mergable constant section.
+ return SectionKind::RODataMergeConst;
+
+ case Constant::LocalRelocation:
+ // In static relocation model, the linker will resolve all addresses, so
+ // the relocation entries will actually be constants by the time the app
+ // starts up.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::ROData;
+
+ // Otherwise, the dynamic linker needs to fix it up, put it in the
+ // writable data.rel.local section.
+ return SectionKind::DataRelROLocal;
+
+ case Constant::GlobalRelocations:
+ // In static relocation model, the linker will resolve all addresses, so
+ // the relocation entries will actually be constants by the time the app
+ // starts up.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::ROData;
+
+ // Otherwise, the dynamic linker needs to fix it up, put it in the
+ // writable data.rel section.
+ return SectionKind::DataRelRO;
+ }
+ }
+
+ // Okay, this isn't a constant. If the initializer for the global is going
+ // to require a runtime relocation by the dynamic linker, put it into a more
+ // specific section to improve startup time of the app. This coalesces these
+ // globals together onto fewer pages, improving the locality of the dynamic
+ // linker.
+ if (ReloModel == Reloc::Static)
+ return SectionKind::Data;
+
+ switch (C->getRelocationInfo()) {
+ default: llvm_unreachable("unknown relocation info kind");
+ case Constant::NoRelocation: return SectionKind::Data;
+ case Constant::LocalRelocation: return SectionKind::DataRelLocal;
+ case Constant::GlobalRelocations: return SectionKind::DataRel;
+ }
+}
+
+
+const Section *TargetAsmInfo::SectionForGlobal(const GlobalValue *GV) const {
+ SectionKind::Kind Kind = SectionKindForGlobal(GV, TM.getRelocationModel());
+
+ // Select section name.
+ if (GV->hasSection()) {
+ // If the target has special section hacks for specifically named globals,
+ // return them now.
+ if (const Section *TS = getSpecialCasedSectionGlobals(GV, Kind))
+ return TS;
+
+ // Honour section already set, if any.
+ unsigned Flags = SectionFlagsForGlobal(GV, Kind);
+
+ // This is an explicitly named section.
+ Flags |= SectionFlags::Named;
+
+ // If the target has magic semantics for certain section names, make sure to
+ // pick up the flags. This allows the user to write things with attribute
+ // section and still get the appropriate section flags printed.
+ Flags |= getFlagsForNamedSection(GV->getSection().c_str());
+
+ return getNamedSection(GV->getSection().c_str(), Flags);
+ }
+
+ // If this global is linkonce/weak and the target handles this by emitting it
+ // into a 'uniqued' section name, create and return the section now.
+ if (GV->isWeakForLinker()) {
+ if (const char *Prefix = getSectionPrefixForUniqueGlobal(Kind)) {
+ unsigned Flags = SectionFlagsForGlobal(GV, Kind);
+
+ // FIXME: Use mangler interface (PR4584).
+ std::string Name = Prefix+GV->getNameStr();
+ return getNamedSection(Name.c_str(), Flags);
+ }
+ }
+
+ // Use default section depending on the 'type' of global
+ return SelectSectionForGlobal(GV, Kind);
+}
+
+// Lame default implementation. Calculate the section name for global.
+const Section*
+TargetAsmInfo::SelectSectionForGlobal(const GlobalValue *GV,
+ SectionKind::Kind Kind) const {
+ if (Kind == SectionKind::Text)
+ return getTextSection();
+
+ if (isBSS(Kind))
+ if (const Section *S = getBSSSection_())
+ return S;
+
+ if (SectionKind::isReadOnly(Kind))
+ if (const Section *S = getReadOnlySection())
+ return S;
+
+ return getDataSection();
+}
+
+/// getSectionForMergableConstant - Given a mergable constant with the
+/// specified size and relocation information, return a section that it
+/// should be placed in.
+const Section *
+TargetAsmInfo::getSectionForMergableConstant(uint64_t Size,
+ unsigned ReloInfo) const {
+ // FIXME: Support data.rel stuff someday
+ // Lame default implementation. Calculate the section name for machine const.
+ return getDataSection();
+}
+
+
+
+
+const char *
+TargetAsmInfo::getSectionPrefixForUniqueGlobal(SectionKind::Kind Kind) const {
+ switch (Kind) {
+ default: llvm_unreachable("Unknown section kind");
+ case SectionKind::Text: return ".gnu.linkonce.t.";
+ case SectionKind::Data: return ".gnu.linkonce.d.";
+ case SectionKind::DataRel: return ".gnu.linkonce.d.rel.";
+ case SectionKind::DataRelLocal: return ".gnu.linkonce.d.rel.local.";
+ case SectionKind::DataRelRO: return ".gnu.linkonce.d.rel.ro.";
+ case SectionKind::DataRelROLocal: return ".gnu.linkonce.d.rel.ro.local.";
+ case SectionKind::BSS: return ".gnu.linkonce.b.";
+ case SectionKind::ROData:
+ case SectionKind::RODataMergeConst:
+ case SectionKind::RODataMergeStr: return ".gnu.linkonce.r.";
+ case SectionKind::ThreadData: return ".gnu.linkonce.td.";
+ case SectionKind::ThreadBSS: return ".gnu.linkonce.tb.";
+ }
+}
+
+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;
+}
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