#define DEBUG_TYPE "elfwriter"
+#include "ELF.h"
#include "ELFWriter.h"
#include "ELFCodeEmitter.h"
-#include "ELF.h"
#include "llvm/Constants.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/CodeGen/BinaryObject.h"
#include "llvm/CodeGen/FileWriters.h"
#include "llvm/CodeGen/MachineCodeEmitter.h"
+#include "llvm/CodeGen/ObjectCodeEmitter.h"
+#include "llvm/CodeGen/MachineCodeEmitter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetELFWriterInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Support/Streams.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Debug.h"
-#include <list>
+#include "llvm/Support/ErrorHandling.h"
+
using namespace llvm;
char ELFWriter::ID = 0;
-/// AddELFWriter - Concrete function to add the ELF writer to the function pass
-/// manager.
-MachineCodeEmitter *llvm::AddELFWriter(PassManagerBase &PM,
- raw_ostream &O,
- TargetMachine &TM) {
+
+/// AddELFWriter - Add the ELF writer to the function pass manager
+ObjectCodeEmitter *llvm::AddELFWriter(PassManagerBase &PM,
+ raw_ostream &O,
+ TargetMachine &TM) {
ELFWriter *EW = new ELFWriter(O, TM);
PM.add(EW);
- return &EW->getMachineCodeEmitter();
+ return EW->getObjectCodeEmitter();
}
//===----------------------------------------------------------------------===//
TAI = TM.getTargetAsmInfo();
TEW = TM.getELFWriterInfo();
- // Create the machine code emitter object for this target.
- MCE = new ELFCodeEmitter(*this);
+ // Create the object code emitter object for this target.
+ ElfCE = new ELFCodeEmitter(*this);
// Inital number of sections
NumSections = 0;
}
ELFWriter::~ELFWriter() {
- delete MCE;
+ delete ElfCE;
}
// doInitialization - Emit the file header and all of the global variables for
ElfHdr.emitWord16(0); // Placeholder
// Add the null section, which is required to be first in the file.
- getSection("", ELFSection::SHT_NULL, 0);
-
- // Start up the symbol table. The first entry in the symtab is the null
- // entry.
- SymbolList.push_back(ELFSym(0));
+ getNullSection();
return false;
}
-void ELFWriter::EmitGlobal(GlobalVariable *GV) {
-
- // XXX: put local symbols *before* global ones!
- const Section *S = TAI->SectionForGlobal(GV);
- DOUT << "Section " << S->getName() << " for global " << GV->getName() << "\n";
-
- // If this is an external global, emit it now. TODO: Note that it would be
- // better to ignore the symbol here and only add it to the symbol table if
- // referenced.
- if (!GV->hasInitializer()) {
- ELFSym ExternalSym(GV);
- ExternalSym.SetBind(ELFSym::STB_GLOBAL);
- ExternalSym.SetType(ELFSym::STT_NOTYPE);
- ExternalSym.SectionIdx = ELFSection::SHN_UNDEF;
- SymbolList.push_back(ExternalSym);
- return;
+// getGlobalELFVisibility - Returns the ELF specific visibility type
+unsigned ELFWriter::getGlobalELFVisibility(const GlobalValue *GV) {
+ switch (GV->getVisibility()) {
+ default:
+ llvm_unreachable("unknown visibility type");
+ case GlobalValue::DefaultVisibility:
+ return ELFSym::STV_DEFAULT;
+ case GlobalValue::HiddenVisibility:
+ return ELFSym::STV_HIDDEN;
+ case GlobalValue::ProtectedVisibility:
+ return ELFSym::STV_PROTECTED;
}
+ return 0;
+}
- const TargetData *TD = TM.getTargetData();
- unsigned Align = TD->getPreferredAlignment(GV);
- Constant *CV = GV->getInitializer();
- unsigned Size = TD->getTypeAllocSize(CV->getType());
+// getGlobalELFBinding - Returns the ELF specific binding type
+unsigned ELFWriter::getGlobalELFBinding(const GlobalValue *GV) {
+ if (GV->hasInternalLinkage())
+ return ELFSym::STB_LOCAL;
- // If this global has a zero initializer, go to .bss or common section.
- if (CV->isNullValue() || isa<UndefValue>(CV)) {
- // If this global is part of the common block, add it now. Variables are
- // part of the common block if they are zero initialized and allowed to be
- // merged with other symbols.
- if (GV->hasLinkOnceLinkage() || GV->hasWeakLinkage() ||
- GV->hasCommonLinkage()) {
- ELFSym CommonSym(GV);
- // Value for common symbols is the alignment required.
- CommonSym.Value = Align;
- CommonSym.Size = Size;
- CommonSym.SetBind(ELFSym::STB_GLOBAL);
- CommonSym.SetType(ELFSym::STT_OBJECT);
- CommonSym.SectionIdx = ELFSection::SHN_COMMON;
- SymbolList.push_back(CommonSym);
- getSection(S->getName(), ELFSection::SHT_NOBITS,
- ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC, 1);
- return;
- }
+ if (GV->hasWeakLinkage())
+ return ELFSym::STB_WEAK;
- // Otherwise, this symbol is part of the .bss section. Emit it now.
- // Handle alignment. Ensure section is aligned at least as much as required
- // by this symbol.
- ELFSection &BSSSection = getBSSSection();
- BSSSection.Align = std::max(BSSSection.Align, Align);
-
- // Within the section, emit enough virtual padding to get us to an alignment
- // boundary.
- if (Align)
- BSSSection.Size = (BSSSection.Size + Align - 1) & ~(Align-1);
-
- ELFSym BSSSym(GV);
- BSSSym.Value = BSSSection.Size;
- BSSSym.Size = Size;
- BSSSym.SetType(ELFSym::STT_OBJECT);
-
- switch (GV->getLinkage()) {
- default: // weak/linkonce/common handled above
- assert(0 && "Unexpected linkage type!");
- case GlobalValue::AppendingLinkage: // FIXME: This should be improved!
- case GlobalValue::ExternalLinkage:
- BSSSym.SetBind(ELFSym::STB_GLOBAL);
- break;
- case GlobalValue::InternalLinkage:
- BSSSym.SetBind(ELFSym::STB_LOCAL);
- break;
- }
+ return ELFSym::STB_GLOBAL;
+}
- // Set the idx of the .bss section
- BSSSym.SectionIdx = BSSSection.SectionIdx;
- if (!GV->hasPrivateLinkage())
- SymbolList.push_back(BSSSym);
+// getGlobalELFType - Returns the ELF specific type for a global
+unsigned ELFWriter::getGlobalELFType(const GlobalValue *GV) {
+ if (GV->isDeclaration())
+ return ELFSym::STT_NOTYPE;
- // Reserve space in the .bss section for this symbol.
- BSSSection.Size += Size;
- return;
- }
+ if (isa<Function>(GV))
+ return ELFSym::STT_FUNC;
- /// Emit the Global symbol to the right ELF section
- ELFSym GblSym(GV);
- GblSym.Size = Size;
- GblSym.SetType(ELFSym::STT_OBJECT);
- GblSym.SetBind(ELFSym::STB_GLOBAL);
- unsigned Flags = S->getFlags();
- unsigned SectType = ELFSection::SHT_PROGBITS;
- unsigned SHdrFlags = ELFSection::SHF_ALLOC;
+ return ELFSym::STT_OBJECT;
+}
+
+// getElfSectionFlags - Get the ELF Section Header flags based
+// on the flags defined in ELFTargetAsmInfo.
+unsigned ELFWriter::getElfSectionFlags(unsigned Flags) {
+ unsigned ElfSectionFlags = ELFSection::SHF_ALLOC;
if (Flags & SectionFlags::Code)
- SHdrFlags |= ELFSection::SHF_EXECINSTR;
+ ElfSectionFlags |= ELFSection::SHF_EXECINSTR;
if (Flags & SectionFlags::Writeable)
- SHdrFlags |= ELFSection::SHF_WRITE;
+ ElfSectionFlags |= ELFSection::SHF_WRITE;
if (Flags & SectionFlags::Mergeable)
- SHdrFlags |= ELFSection::SHF_MERGE;
+ ElfSectionFlags |= ELFSection::SHF_MERGE;
if (Flags & SectionFlags::TLS)
- SHdrFlags |= ELFSection::SHF_TLS;
+ ElfSectionFlags |= ELFSection::SHF_TLS;
if (Flags & SectionFlags::Strings)
- SHdrFlags |= ELFSection::SHF_STRINGS;
-
- // Remove tab from section name prefix
- std::string SectionName(S->getName());
- size_t Pos = SectionName.find("\t");
- if (Pos != std::string::npos)
- SectionName.erase(Pos, 1);
-
- // The section alignment should be bound to the element with
- // the largest alignment
- ELFSection &ElfS = getSection(SectionName, SectType, SHdrFlags);
- GblSym.SectionIdx = ElfS.SectionIdx;
- if (Align > ElfS.Align)
- ElfS.Align = Align;
-
- // S.Value should contain the symbol index inside the section,
- // and all symbols should start on their required alignment boundary
- GblSym.Value = (ElfS.size() + (Align-1)) & (-Align);
- ElfS.emitAlignment(Align);
-
- // Emit the constant symbol to its section
- EmitGlobalConstant(CV, ElfS);
- SymbolList.push_back(GblSym);
+ ElfSectionFlags |= ELFSection::SHF_STRINGS;
+
+ return ElfSectionFlags;
+}
+
+// isELFUndefSym - the symbol has no section and must be placed in
+// the symbol table with a reference to the null section.
+static bool isELFUndefSym(const GlobalValue *GV) {
+ return GV->isDeclaration();
+}
+
+// isELFBssSym - for an undef or null value, the symbol must go to a bss
+// section if it's not weak for linker, otherwise it's a common sym.
+static bool isELFBssSym(const GlobalValue *GV) {
+ return (!GV->isDeclaration() &&
+ (GV->isNullValue() || isa<UndefValue>(GV)) &&
+ !GV->isWeakForLinker());
+}
+
+// isELFCommonSym - for an undef or null value, the symbol must go to a
+// common section if it's weak for linker, otherwise bss.
+static bool isELFCommonSym(const GlobalValue *GV) {
+ return (!GV->isDeclaration() &&
+ (GV->isNullValue() || isa<UndefValue>(GV))
+ && GV->isWeakForLinker());
+}
+
+// isELFDataSym - if the symbol is an initialized but no null constant
+// it must go to some kind of data section gathered from TAI
+static bool isELFDataSym(const GlobalValue *GV) {
+ return (!GV->isDeclaration() &&
+ !(GV->isNullValue() || isa<UndefValue>(GV)));
+}
+
+// EmitGlobal - Choose the right section for global and emit it
+void ELFWriter::EmitGlobal(const GlobalValue *GV) {
+
+ // Handle ELF Bind, Visibility and Type for the current symbol
+ unsigned SymBind = getGlobalELFBinding(GV);
+ ELFSym *GblSym = new ELFSym(GV);
+ GblSym->setBind(SymBind);
+ GblSym->setVisibility(getGlobalELFVisibility(GV));
+ GblSym->setType(getGlobalELFType(GV));
+
+ if (isELFUndefSym(GV)) {
+ GblSym->SectionIdx = ELFSection::SHN_UNDEF;
+ } else {
+ assert(isa<GlobalVariable>(GV) && "GV not a global variable!");
+ const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
+
+ // Get ELF section from TAI
+ const Section *S = TAI->SectionForGlobal(GV);
+ unsigned SectionFlags = getElfSectionFlags(S->getFlags());
+
+ // The symbol align should update the section alignment if needed
+ const TargetData *TD = TM.getTargetData();
+ unsigned Align = TD->getPreferredAlignment(GVar);
+ unsigned Size = TD->getTypeAllocSize(GVar->getInitializer()->getType());
+ GblSym->Size = Size;
+
+ if (isELFCommonSym(GV)) {
+ GblSym->SectionIdx = ELFSection::SHN_COMMON;
+ getSection(S->getName(), ELFSection::SHT_NOBITS, SectionFlags, 1);
+
+ // A new linkonce section is created for each global in the
+ // common section, the default alignment is 1 and the symbol
+ // value contains its alignment.
+ GblSym->Value = Align;
+
+ } else if (isELFBssSym(GV)) {
+ ELFSection &ES =
+ getSection(S->getName(), ELFSection::SHT_NOBITS, SectionFlags);
+ GblSym->SectionIdx = ES.SectionIdx;
+
+ // Update the size with alignment and the next object can
+ // start in the right offset in the section
+ if (Align) ES.Size = (ES.Size + Align-1) & ~(Align-1);
+ ES.Align = std::max(ES.Align, Align);
+
+ // GblSym->Value should contain the virtual offset inside the section.
+ // Virtual because the BSS space is not allocated on ELF objects
+ GblSym->Value = ES.Size;
+ ES.Size += Size;
+
+ } else if (isELFDataSym(GV)) {
+ ELFSection &ES =
+ getSection(S->getName(), ELFSection::SHT_PROGBITS, SectionFlags);
+ GblSym->SectionIdx = ES.SectionIdx;
+
+ // GblSym->Value should contain the symbol offset inside the section,
+ // and all symbols should start on their required alignment boundary
+ ES.Align = std::max(ES.Align, Align);
+ GblSym->Value = (ES.size() + (Align-1)) & (-Align);
+ ES.emitAlignment(ES.Align);
+
+ // Emit the global to the data section 'ES'
+ EmitGlobalConstant(GVar->getInitializer(), ES);
+ }
+ }
+
+ if (!GV->hasPrivateLinkage())
+ SymbolList.push_back(GblSym);
}
void ELFWriter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
if (CVA->isString()) {
std::string GblStr = CVA->getAsString();
+ GblStr.resize(GblStr.size()-1);
GblS.emitString(GblStr);
} else { // Not a string. Print the values in successive locations
for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
else if (CFP->getType() == Type::FloatTy)
GblS.emitWord32(Val);
else if (CFP->getType() == Type::X86_FP80Ty) {
- assert(0 && "X86_FP80Ty global emission not implemented");
+ llvm_unreachable("X86_FP80Ty global emission not implemented");
} else if (CFP->getType() == Type::PPC_FP128Ty)
- assert(0 && "PPC_FP128Ty global emission not implemented");
+ llvm_unreachable("PPC_FP128Ty global emission not implemented");
return;
} else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
if (Size == 4)
else if (Size == 8)
GblS.emitWord64(CI->getZExtValue());
else
- assert(0 && "LargeInt global emission not implemented");
+ llvm_unreachable("LargeInt global emission not implemented");
return;
} else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
const VectorType *PTy = CP->getType();
EmitGlobalConstant(CP->getOperand(I), GblS);
return;
}
- assert(0 && "unknown global constant");
+ llvm_unreachable("unknown global constant");
}
bool ELFWriter::runOnMachineFunction(MachineFunction &MF) {
- // Nothing to do here, this is all done through the MCE object above.
+ // Nothing to do here, this is all done through the ElfCE object above.
return false;
}
/// doFinalization - Now that the module has been completely processed, emit
/// the ELF file to 'O'.
bool ELFWriter::doFinalization(Module &M) {
- /// FIXME: This should be removed when moving to ObjectCodeEmiter. Since the
- /// current ELFCodeEmiter uses CurrBuff, ... it doesn't update S.Data
- /// vector size for .text sections, so this is a quick dirty fix
- ELFSection &TS = getTextSection();
- if (TS.Size) {
- BinaryData &BD = TS.getData();
- for (unsigned e=0; e<TS.Size; ++e)
- BD.push_back(BD[e]);
- }
-
// Emit .data section placeholder
getDataSection();
// Build and emit data, bss and "common" sections.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
- I != E; ++I)
+ I != E; ++I) {
EmitGlobal(I);
+ GblSymLookup[I] = 0;
+ }
+
+ // Emit all pending globals
+ // TODO: this should be done only for referenced symbols
+ for (SetVector<GlobalValue*>::const_iterator I = PendingGlobals.begin(),
+ E = PendingGlobals.end(); I != E; ++I) {
+
+ // No need to emit the symbol again
+ if (GblSymLookup.find(*I) != GblSymLookup.end())
+ continue;
+
+ EmitGlobal(*I);
+ GblSymLookup[*I] = 0;
+ }
// Emit non-executable stack note
if (TAI->getNonexecutableStackDirective())
getNonExecStackSection();
+ // Emit a symbol for each section created until now, skip null section
+ for (unsigned i = 1, e = SectionList.size(); i < e; ++i) {
+ ELFSection &ES = *SectionList[i];
+ ELFSym *SectionSym = new ELFSym(0);
+ SectionSym->SectionIdx = ES.SectionIdx;
+ SectionSym->Size = 0;
+ SectionSym->setBind(ELFSym::STB_LOCAL);
+ SectionSym->setType(ELFSym::STT_SECTION);
+ SectionSym->setVisibility(ELFSym::STV_DEFAULT);
+ SymbolList.push_back(SectionSym);
+ ES.Sym = SymbolList.back();
+ }
+
+ // Emit string table
+ EmitStringTable();
+
// Emit the symbol table now, if non-empty.
EmitSymbolTable();
OutputSectionsAndSectionTable();
// We are done with the abstract symbols.
+ SymbolList.clear();
SectionList.clear();
NumSections = 0;
/// EmitRelocations - Emit relocations
void ELFWriter::EmitRelocations() {
+
+ // Create Relocation sections for each section which needs it.
+ for (unsigned i=0, e=SectionList.size(); i != e; ++i) {
+ ELFSection &S = *SectionList[i];
+
+ // This section does not have relocations
+ if (!S.hasRelocations()) continue;
+
+ // Get the relocation section for section 'S'
+ bool HasRelA = TEW->hasRelocationAddend();
+ ELFSection &RelSec = getRelocSection(S.getName(), HasRelA,
+ TEW->getPrefELFAlignment());
+
+ // 'Link' - Section hdr idx of the associated symbol table
+ // 'Info' - Section hdr idx of the section to which the relocation applies
+ ELFSection &SymTab = getSymbolTableSection();
+ RelSec.Link = SymTab.SectionIdx;
+ RelSec.Info = S.SectionIdx;
+ RelSec.EntSize = TEW->getRelocationEntrySize();
+
+ // Get the relocations from Section
+ std::vector<MachineRelocation> Relos = S.getRelocations();
+ for (std::vector<MachineRelocation>::iterator MRI = Relos.begin(),
+ MRE = Relos.end(); MRI != MRE; ++MRI) {
+ MachineRelocation &MR = *MRI;
+
+ // Offset from the start of the section containing the symbol
+ unsigned Offset = MR.getMachineCodeOffset();
+
+ // Symbol index in the symbol table
+ unsigned SymIdx = 0;
+
+ // Target specific ELF relocation type
+ unsigned RelType = TEW->getRelocationType(MR.getRelocationType());
+
+ // Constant addend used to compute the value to be stored
+ // into the relocatable field
+ int64_t Addend = 0;
+
+ // There are several machine relocations types, and each one of
+ // them needs a different approach to retrieve the symbol table index.
+ if (MR.isGlobalValue()) {
+ const GlobalValue *G = MR.getGlobalValue();
+ SymIdx = GblSymLookup[G];
+ Addend = TEW->getAddendForRelTy(RelType);
+ } else {
+ // Get the symbol index for the section symbol referenced
+ // by the relocation
+ unsigned SectionIdx = MR.getConstantVal();
+ SymIdx = SectionList[SectionIdx]->Sym->SymTabIdx;
+ Addend = (uint64_t)MR.getResultPointer();
+ }
+
+ // Get the relocation entry and emit to the relocation section
+ ELFRelocation Rel(Offset, SymIdx, RelType, HasRelA, Addend);
+ EmitRelocation(RelSec, Rel, HasRelA);
+ }
+ }
+}
+
+/// EmitRelocation - Write relocation 'Rel' to the relocation section 'Rel'
+void ELFWriter::EmitRelocation(BinaryObject &RelSec, ELFRelocation &Rel,
+ bool HasRelA) {
+ RelSec.emitWord(Rel.getOffset());
+ RelSec.emitWord(Rel.getInfo(is64Bit));
+ if (HasRelA)
+ RelSec.emitWord(Rel.getAddend());
}
/// EmitSymbol - Write symbol 'Sym' to the symbol table 'SymbolTable'
/// EmitSectionHeader - Write section 'Section' header in 'SHdrTab'
/// Section Header Table
-void ELFWriter::EmitSectionHeader(BinaryObject &SHdrTab,
+void ELFWriter::EmitSectionHeader(BinaryObject &SHdrTab,
const ELFSection &SHdr) {
SHdrTab.emitWord32(SHdr.NameIdx);
SHdrTab.emitWord32(SHdr.Type);
}
}
-/// EmitSymbolTable - If the current symbol table is non-empty, emit the string
-/// table for it and then the symbol table itself.
-void ELFWriter::EmitSymbolTable() {
- if (SymbolList.size() == 1) return; // Only the null entry.
-
- // FIXME: compact all local symbols to the start of the symtab.
- unsigned FirstNonLocalSymbol = 1;
-
+/// EmitStringTable - If the current symbol table is non-empty, emit the string
+/// table for it
+void ELFWriter::EmitStringTable() {
+ if (!SymbolList.size()) return; // Empty symbol table.
ELFSection &StrTab = getStringTableSection();
// Set the zero'th symbol to a null byte, as required.
StrTab.emitByte(0);
+ // Walk on the symbol list and write symbol names into the string table.
unsigned Index = 1;
- for (unsigned i = 1, e = SymbolList.size(); i != e; ++i) {
+ for (ELFSymIter I=SymbolList.begin(), E=SymbolList.end(); I != E; ++I) {
+ ELFSym &Sym = *(*I);
+
// Use the name mangler to uniquify the LLVM symbol.
- std::string Name = Mang->getValueName(SymbolList[i].GV);
+ std::string Name;
+ if (Sym.GV) Name.append(Mang->getMangledName(Sym.GV));
if (Name.empty()) {
- SymbolList[i].NameIdx = 0;
+ Sym.NameIdx = 0;
} else {
- SymbolList[i].NameIdx = Index;
+ Sym.NameIdx = Index;
StrTab.emitString(Name);
// Keep track of the number of bytes emitted to this section.
}
assert(Index == StrTab.size());
StrTab.Size = Index;
+}
+
+// SortSymbols - On the symbol table local symbols must come before
+// all other symbols with non-local bindings. The return value is
+// the position of the first non local symbol.
+unsigned ELFWriter::SortSymbols() {
+ unsigned FirstNonLocalSymbol;
+ std::vector<ELFSym*> LocalSyms, OtherSyms;
+
+ for (ELFSymIter I=SymbolList.begin(), E=SymbolList.end(); I != E; ++I) {
+ if ((*I)->isLocalBind())
+ LocalSyms.push_back(*I);
+ else
+ OtherSyms.push_back(*I);
+ }
+ SymbolList.clear();
+ FirstNonLocalSymbol = LocalSyms.size();
+
+ for (unsigned i = 0; i < FirstNonLocalSymbol; ++i)
+ SymbolList.push_back(LocalSyms[i]);
+
+ for (ELFSymIter I=OtherSyms.begin(), E=OtherSyms.end(); I != E; ++I)
+ SymbolList.push_back(*I);
+
+ LocalSyms.clear();
+ OtherSyms.clear();
+
+ return FirstNonLocalSymbol;
+}
+
+/// EmitSymbolTable - Emit the symbol table itself.
+void ELFWriter::EmitSymbolTable() {
+ if (!SymbolList.size()) return; // Empty symbol table.
// Now that we have emitted the string table and know the offset into the
// string table of each symbol, emit the symbol table itself.
ELFSection &SymTab = getSymbolTableSection();
- SymTab.Align = TEW->getSymTabAlignment();
- SymTab.Link = StrTab.SectionIdx; // Section Index of .strtab.
- SymTab.Info = FirstNonLocalSymbol; // First non-STB_LOCAL symbol.
+ SymTab.Align = TEW->getPrefELFAlignment();
+
+ // Section Index of .strtab.
+ SymTab.Link = getStringTableSection().SectionIdx;
// Size of each symtab entry.
SymTab.EntSize = TEW->getSymTabEntrySize();
- for (unsigned i = 0, e = SymbolList.size(); i != e; ++i)
- EmitSymbol(SymTab, SymbolList[i]);
+ // The first entry in the symtab is the null symbol
+ SymbolList.insert(SymbolList.begin(), new ELFSym(0));
+
+ // Reorder the symbol table with local symbols first!
+ unsigned FirstNonLocalSymbol = SortSymbols();
+
+ // Emit all the symbols to the symbol table.
+ for (unsigned i = 0, e = SymbolList.size(); i < e; ++i) {
+ ELFSym &Sym = *SymbolList[i];
+ // Emit symbol to the symbol table
+ EmitSymbol(SymTab, Sym);
+
+ // Record the symbol table index for each global value
+ if (Sym.GV) GblSymLookup[Sym.GV] = i;
+
+ // Keep track on the symbol index into the symbol table
+ Sym.SymTabIdx = i;
+ }
+
+ // One greater than the symbol table index of the last local symbol
+ SymTab.Info = FirstNonLocalSymbol;
SymTab.Size = SymTab.size();
}
/// section names.
void ELFWriter::EmitSectionTableStringTable() {
// First step: add the section for the string table to the list of sections:
- ELFSection &SHStrTab = getSection(".shstrtab", ELFSection::SHT_STRTAB, 0);
+ ELFSection &SHStrTab = getSectionHeaderStringTableSection();
// Now that we know which section number is the .shstrtab section, update the
// e_shstrndx entry in the ELF header.
// the string table.
unsigned Index = 0;
- for (std::list<ELFSection>::iterator I = SectionList.begin(),
- E = SectionList.end(); I != E; ++I) {
+ for (ELFSectionIter I=SectionList.begin(), E=SectionList.end(); I != E; ++I) {
+ ELFSection &S = *(*I);
// Set the index into the table. Note if we have lots of entries with
// common suffixes, we could memoize them here if we cared.
- I->NameIdx = Index;
- SHStrTab.emitString(I->getName());
+ S.NameIdx = Index;
+ SHStrTab.emitString(S.getName());
// Keep track of the number of bytes emitted to this section.
- Index += I->getName().size()+1;
+ Index += S.getName().size()+1;
}
// Set the size of .shstrtab now that we know what it is.
// Pass #1: Compute the file offset for each section.
size_t FileOff = ElfHdr.size(); // File header first.
- // Adjust alignment of all section if needed.
- for (std::list<ELFSection>::iterator I = SectionList.begin(),
- E = SectionList.end(); I != E; ++I) {
-
- // Section idx 0 has 0 offset
- if (!I->SectionIdx)
- continue;
-
- if (!I->size()) {
- I->Offset = FileOff;
+ // Adjust alignment of all section if needed, skip the null section.
+ for (unsigned i=1, e=SectionList.size(); i < e; ++i) {
+ ELFSection &ES = *SectionList[i];
+ if (!ES.size()) {
+ ES.Offset = FileOff;
continue;
}
// Update Section size
- if (!I->Size)
- I->Size = I->size();
+ if (!ES.Size)
+ ES.Size = ES.size();
// Align FileOff to whatever the alignment restrictions of the section are.
- if (I->Align)
- FileOff = (FileOff+I->Align-1) & ~(I->Align-1);
+ if (ES.Align)
+ FileOff = (FileOff+ES.Align-1) & ~(ES.Align-1);
- I->Offset = FileOff;
- FileOff += I->Size;
+ ES.Offset = FileOff;
+ FileOff += ES.Size;
}
// Align Section Header.
- unsigned TableAlign = is64Bit ? 8 : 4;
+ unsigned TableAlign = TEW->getPrefELFAlignment();
FileOff = (FileOff+TableAlign-1) & ~(TableAlign-1);
// Now that we know where all of the sections will be emitted, set the e_shnum
BinaryObject SHdrTable(isLittleEndian, is64Bit);
// Emit all of sections to the file and build the section header table.
- while (!SectionList.empty()) {
- ELFSection &S = *SectionList.begin();
+ for (ELFSectionIter I=SectionList.begin(), E=SectionList.end(); I != E; ++I) {
+ ELFSection &S = *(*I);
DOUT << "SectionIdx: " << S.SectionIdx << ", Name: " << S.getName()
<< ", Size: " << S.Size << ", Offset: " << S.Offset
<< ", SectionData Size: " << S.size() << "\n";
// Align FileOff to whatever the alignment restrictions of the section are.
- if (S.Align) {
- for (size_t NewFileOff = (FileOff+S.Align-1) & ~(S.Align-1);
- FileOff != NewFileOff; ++FileOff)
- O << (char)0xAB;
- }
-
if (S.size()) {
+ if (S.Align) {
+ for (size_t NewFileOff = (FileOff+S.Align-1) & ~(S.Align-1);
+ FileOff != NewFileOff; ++FileOff)
+ O << (char)0xAB;
+ }
O.write((char *)&S.getData()[0], S.Size);
FileOff += S.Size;
}
EmitSectionHeader(SHdrTable, S);
- SectionList.pop_front();
}
// Align output for the section table.
projects / oota-llvm.git / blobdiff