// ...
// #N. ".shstrtab" entry - String table for the section names.
//
-// NOTE: This code should eventually be extended to support 64-bit ELF (this
-// won't be hard), but we haven't done so yet!
-//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "elfwriter"
#include "ELFWriter.h"
#include "ELFCodeEmitter.h"
#include "ELF.h"
+#include "llvm/Constants.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/DerivedTypes.h"
+#include "llvm/CodeGen/BinaryObject.h"
#include "llvm/CodeGen/FileWriters.h"
#include "llvm/CodeGen/MachineCodeEmitter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetELFWriterInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Support/Mangler.h"
-#include "llvm/Support/OutputBuffer.h"
#include "llvm/Support/Streams.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Debug.h"
//===----------------------------------------------------------------------===//
ELFWriter::ELFWriter(raw_ostream &o, TargetMachine &tm)
- : MachineFunctionPass(&ID), O(o), TM(tm), ElfHdr() {
- is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64;
- isLittleEndian = TM.getTargetData()->isLittleEndian();
+ : MachineFunctionPass(&ID), O(o), TM(tm),
+ is64Bit(TM.getTargetData()->getPointerSizeInBits() == 64),
+ isLittleEndian(TM.getTargetData()->isLittleEndian()),
+ ElfHdr(isLittleEndian, is64Bit) {
- ElfHdr = new ELFHeader(TM.getELFWriterInfo()->getEMachine(), 0,
- is64Bit, isLittleEndian);
+ TAI = TM.getTargetAsmInfo();
+ TEW = TM.getELFWriterInfo();
// Create the machine code emitter object for this target.
MCE = new ELFCodeEmitter(*this);
+
+ // Inital number of sections
NumSections = 0;
}
ELFWriter::~ELFWriter() {
delete MCE;
- delete ElfHdr;
}
// doInitialization - Emit the file header and all of the global variables for
bool ELFWriter::doInitialization(Module &M) {
Mang = new Mangler(M);
- // Local alias to shortenify coming code.
- std::vector<unsigned char> &FH = FileHeader;
- OutputBuffer FHOut(FH, is64Bit, isLittleEndian);
-
// ELF Header
// ----------
// Fields e_shnum e_shstrndx are only known after all section have
//
// Note
// ----
- // FHOut.outaddr method behaves differently for ELF32 and ELF64 writing
+ // emitWord method behaves differently for ELF32 and ELF64, writing
// 4 bytes in the former and 8 in the last for *_off and *_addr elf types
- FHOut.outbyte(0x7f); // e_ident[EI_MAG0]
- FHOut.outbyte('E'); // e_ident[EI_MAG1]
- FHOut.outbyte('L'); // e_ident[EI_MAG2]
- FHOut.outbyte('F'); // e_ident[EI_MAG3]
-
- FHOut.outbyte(ElfHdr->getElfClass()); // e_ident[EI_CLASS]
- FHOut.outbyte(ElfHdr->getByteOrder()); // e_ident[EI_DATA]
- FHOut.outbyte(EV_CURRENT); // e_ident[EI_VERSION]
-
- FH.resize(16); // e_ident[EI_NIDENT-EI_PAD]
-
- FHOut.outhalf(ET_REL); // e_type
- FHOut.outhalf(ElfHdr->getMachine()); // e_machine = target
- FHOut.outword(EV_CURRENT); // e_version
- FHOut.outaddr(0); // e_entry = 0, no entry point in .o file
- FHOut.outaddr(0); // e_phoff = 0, no program header for .o
- ELFHdr_e_shoff_Offset = FH.size();
- FHOut.outaddr(0); // e_shoff = sec hdr table off in bytes
- FHOut.outword(ElfHdr->getFlags()); // e_flags = whatever the target wants
- FHOut.outhalf(ElfHdr->getSize()); // e_ehsize = ELF header size
- FHOut.outhalf(0); // e_phentsize = prog header entry size
- FHOut.outhalf(0); // e_phnum = # prog header entries = 0
+ ElfHdr.emitByte(0x7f); // e_ident[EI_MAG0]
+ ElfHdr.emitByte('E'); // e_ident[EI_MAG1]
+ ElfHdr.emitByte('L'); // e_ident[EI_MAG2]
+ ElfHdr.emitByte('F'); // e_ident[EI_MAG3]
+
+ ElfHdr.emitByte(TEW->getEIClass()); // e_ident[EI_CLASS]
+ ElfHdr.emitByte(TEW->getEIData()); // e_ident[EI_DATA]
+ ElfHdr.emitByte(EV_CURRENT); // e_ident[EI_VERSION]
+ ElfHdr.emitAlignment(16); // e_ident[EI_NIDENT-EI_PAD]
+
+ ElfHdr.emitWord16(ET_REL); // e_type
+ ElfHdr.emitWord16(TEW->getEMachine()); // e_machine = target
+ ElfHdr.emitWord32(EV_CURRENT); // e_version
+ ElfHdr.emitWord(0); // e_entry, no entry point in .o file
+ ElfHdr.emitWord(0); // e_phoff, no program header for .o
+ ELFHdr_e_shoff_Offset = ElfHdr.size();
+ ElfHdr.emitWord(0); // e_shoff = sec hdr table off in bytes
+ ElfHdr.emitWord32(TEW->getEFlags()); // e_flags = whatever the target wants
+ ElfHdr.emitWord16(TEW->getHdrSize()); // e_ehsize = ELF header size
+ ElfHdr.emitWord16(0); // e_phentsize = prog header entry size
+ ElfHdr.emitWord16(0); // e_phnum = # prog header entries = 0
// e_shentsize = Section header entry size
- FHOut.outhalf(ELFSection::getSectionHdrSize(is64Bit));
+ ElfHdr.emitWord16(TEW->getSHdrSize());
// e_shnum = # of section header ents
- ELFHdr_e_shnum_Offset = FH.size();
- FHOut.outhalf(0);
+ ELFHdr_e_shnum_Offset = ElfHdr.size();
+ ElfHdr.emitWord16(0); // Placeholder
// e_shstrndx = Section # of '.shstrtab'
- ELFHdr_e_shstrndx_Offset = FH.size();
- FHOut.outhalf(0);
+ ELFHdr_e_shstrndx_Offset = ElfHdr.size();
+ 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
+ // Start up the symbol table. The first entry in the symtab is the null
// entry.
- SymbolTable.push_back(ELFSym(0));
+ SymbolList.push_back(ELFSym(0));
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.
ExternalSym.SetBind(ELFSym::STB_GLOBAL);
ExternalSym.SetType(ELFSym::STT_NOTYPE);
ExternalSym.SectionIdx = ELFSection::SHN_UNDEF;
- SymbolTable.push_back(ExternalSym);
+ SymbolList.push_back(ExternalSym);
return;
}
- unsigned Align = TM.getTargetData()->getPreferredAlignment(GV);
- unsigned Size =
- TM.getTargetData()->getTypeAllocSize(GV->getType()->getElementType());
+ const TargetData *TD = TM.getTargetData();
+ unsigned Align = TD->getPreferredAlignment(GV);
+ Constant *CV = GV->getInitializer();
+ unsigned Size = TD->getTypeAllocSize(CV->getType());
- // If this global has a zero initializer, it is part of the .bss or common
- // section.
- if (GV->getInitializer()->isNullValue()) {
+ // 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.
CommonSym.Size = Size;
CommonSym.SetBind(ELFSym::STB_GLOBAL);
CommonSym.SetType(ELFSym::STT_OBJECT);
- // TODO SOMEDAY: add ELF visibility.
CommonSym.SectionIdx = ELFSection::SHN_COMMON;
- SymbolTable.push_back(CommonSym);
+ SymbolList.push_back(CommonSym);
+ getSection(S->getName(), ELFSection::SHT_NOBITS,
+ ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC, 1);
return;
}
// 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();
// Set the idx of the .bss section
BSSSym.SectionIdx = BSSSection.SectionIdx;
if (!GV->hasPrivateLinkage())
- SymbolTable.push_back(BSSSym);
+ SymbolList.push_back(BSSSym);
// Reserve space in the .bss section for this symbol.
BSSSection.Size += Size;
return;
}
- // FIXME: handle .rodata
- //assert(!GV->isConstant() && "unimp");
+ /// 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;
+
+ if (Flags & SectionFlags::Code)
+ SHdrFlags |= ELFSection::SHF_EXECINSTR;
+ if (Flags & SectionFlags::Writeable)
+ SHdrFlags |= ELFSection::SHF_WRITE;
+ if (Flags & SectionFlags::Mergeable)
+ SHdrFlags |= ELFSection::SHF_MERGE;
+ if (Flags & SectionFlags::TLS)
+ SHdrFlags |= 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);
+}
- // FIXME: handle .data
- //assert(0 && "unimp");
+void ELFWriter::EmitGlobalConstantStruct(const ConstantStruct *CVS,
+ ELFSection &GblS) {
+
+ // Print the fields in successive locations. Pad to align if needed!
+ const TargetData *TD = TM.getTargetData();
+ unsigned Size = TD->getTypeAllocSize(CVS->getType());
+ const StructLayout *cvsLayout = TD->getStructLayout(CVS->getType());
+ uint64_t sizeSoFar = 0;
+ for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
+ const Constant* field = CVS->getOperand(i);
+
+ // Check if padding is needed and insert one or more 0s.
+ uint64_t fieldSize = TD->getTypeAllocSize(field->getType());
+ uint64_t padSize = ((i == e-1 ? Size : cvsLayout->getElementOffset(i+1))
+ - cvsLayout->getElementOffset(i)) - fieldSize;
+ sizeSoFar += fieldSize + padSize;
+
+ // Now print the actual field value.
+ EmitGlobalConstant(field, GblS);
+
+ // Insert padding - this may include padding to increase the size of the
+ // current field up to the ABI size (if the struct is not packed) as well
+ // as padding to ensure that the next field starts at the right offset.
+ for (unsigned p=0; p < padSize; p++)
+ GblS.emitByte(0);
+ }
+ assert(sizeSoFar == cvsLayout->getSizeInBytes() &&
+ "Layout of constant struct may be incorrect!");
+}
+
+void ELFWriter::EmitGlobalConstant(const Constant *CV, ELFSection &GblS) {
+ const TargetData *TD = TM.getTargetData();
+ unsigned Size = TD->getTypeAllocSize(CV->getType());
+
+ if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
+ if (CVA->isString()) {
+ std::string GblStr = CVA->getAsString();
+ GblS.emitString(GblStr);
+ } else { // Not a string. Print the values in successive locations
+ for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
+ EmitGlobalConstant(CVA->getOperand(i), GblS);
+ }
+ return;
+ } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
+ EmitGlobalConstantStruct(CVS, GblS);
+ return;
+ } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
+ uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
+ if (CFP->getType() == Type::DoubleTy)
+ GblS.emitWord64(Val);
+ else if (CFP->getType() == Type::FloatTy)
+ GblS.emitWord32(Val);
+ else if (CFP->getType() == Type::X86_FP80Ty) {
+ assert(0 && "X86_FP80Ty global emission not implemented");
+ } else if (CFP->getType() == Type::PPC_FP128Ty)
+ assert(0 && "PPC_FP128Ty global emission not implemented");
+ return;
+ } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
+ if (Size == 4)
+ GblS.emitWord32(CI->getZExtValue());
+ else if (Size == 8)
+ GblS.emitWord64(CI->getZExtValue());
+ else
+ assert(0 && "LargeInt global emission not implemented");
+ return;
+ } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
+ const VectorType *PTy = CP->getType();
+ for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
+ EmitGlobalConstant(CP->getOperand(I), GblS);
+ return;
+ }
+ assert(0 && "unknown global constant");
}
/// doFinalization - Now that the module has been completely processed, emit
/// the ELF file to 'O'.
bool ELFWriter::doFinalization(Module &M) {
- // Okay, the ELF header and .text sections have been completed, build the
- // .data, .bss, and "common" sections next.
+ /// 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();
+
+ // Emit .bss section placeholder
+ getBSSSection();
+
+ // Build and emit data, bss and "common" sections.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
EmitGlobal(I);
+ // Emit non-executable stack note
+ if (TAI->getNonexecutableStackDirective())
+ getNonExecStackSection();
+
// Emit the symbol table now, if non-empty.
EmitSymbolTable();
// Emit the relocation sections.
EmitRelocations();
- // Emit the string table for the sections in the ELF file.
+ // Emit the sections string table.
EmitSectionTableStringTable();
- // Emit the sections to the .o file, and emit the section table for the file.
+ // Dump the sections and section table to the .o file.
OutputSectionsAndSectionTable();
// We are done with the abstract symbols.
void ELFWriter::EmitRelocations() {
}
+/// EmitSymbol - Write symbol 'Sym' to the symbol table 'SymbolTable'
+void ELFWriter::EmitSymbol(BinaryObject &SymbolTable, ELFSym &Sym) {
+ if (is64Bit) {
+ SymbolTable.emitWord32(Sym.NameIdx);
+ SymbolTable.emitByte(Sym.Info);
+ SymbolTable.emitByte(Sym.Other);
+ SymbolTable.emitWord16(Sym.SectionIdx);
+ SymbolTable.emitWord64(Sym.Value);
+ SymbolTable.emitWord64(Sym.Size);
+ } else {
+ SymbolTable.emitWord32(Sym.NameIdx);
+ SymbolTable.emitWord32(Sym.Value);
+ SymbolTable.emitWord32(Sym.Size);
+ SymbolTable.emitByte(Sym.Info);
+ SymbolTable.emitByte(Sym.Other);
+ SymbolTable.emitWord16(Sym.SectionIdx);
+ }
+}
+
+/// EmitSectionHeader - Write section 'Section' header in 'SHdrTab'
+/// Section Header Table
+void ELFWriter::EmitSectionHeader(BinaryObject &SHdrTab,
+ const ELFSection &SHdr) {
+ SHdrTab.emitWord32(SHdr.NameIdx);
+ SHdrTab.emitWord32(SHdr.Type);
+ if (is64Bit) {
+ SHdrTab.emitWord64(SHdr.Flags);
+ SHdrTab.emitWord(SHdr.Addr);
+ SHdrTab.emitWord(SHdr.Offset);
+ SHdrTab.emitWord64(SHdr.Size);
+ SHdrTab.emitWord32(SHdr.Link);
+ SHdrTab.emitWord32(SHdr.Info);
+ SHdrTab.emitWord64(SHdr.Align);
+ SHdrTab.emitWord64(SHdr.EntSize);
+ } else {
+ SHdrTab.emitWord32(SHdr.Flags);
+ SHdrTab.emitWord(SHdr.Addr);
+ SHdrTab.emitWord(SHdr.Offset);
+ SHdrTab.emitWord32(SHdr.Size);
+ SHdrTab.emitWord32(SHdr.Link);
+ SHdrTab.emitWord32(SHdr.Info);
+ SHdrTab.emitWord32(SHdr.Align);
+ SHdrTab.emitWord32(SHdr.EntSize);
+ }
+}
+
/// 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 (SymbolTable.size() == 1) return; // Only the null entry.
+ if (SymbolList.size() == 1) return; // Only the null entry.
// FIXME: compact all local symbols to the start of the symtab.
unsigned FirstNonLocalSymbol = 1;
- ELFSection &StrTab = getSection(".strtab", ELFSection::SHT_STRTAB, 0);
- StrTab.Align = 1;
-
- DataBuffer &StrTabBuf = StrTab.SectionData;
- OutputBuffer StrTabOut(StrTabBuf, is64Bit, isLittleEndian);
+ ELFSection &StrTab = getStringTableSection();
// Set the zero'th symbol to a null byte, as required.
- StrTabOut.outbyte(0);
+ StrTab.emitByte(0);
+
unsigned Index = 1;
- for (unsigned i = 1, e = SymbolTable.size(); i != e; ++i) {
+ for (unsigned i = 1, e = SymbolList.size(); i != e; ++i) {
// Use the name mangler to uniquify the LLVM symbol.
- std::string Name = Mang->getValueName(SymbolTable[i].GV);
+ std::string Name = Mang->getValueName(SymbolList[i].GV);
if (Name.empty()) {
- SymbolTable[i].NameIdx = 0;
+ SymbolList[i].NameIdx = 0;
} else {
- SymbolTable[i].NameIdx = Index;
-
- // Add the name to the output buffer, including the null terminator.
- StrTabBuf.insert(StrTabBuf.end(), Name.begin(), Name.end());
-
- // Add a null terminator.
- StrTabBuf.push_back(0);
+ SymbolList[i].NameIdx = Index;
+ StrTab.emitString(Name);
// Keep track of the number of bytes emitted to this section.
Index += Name.size()+1;
}
}
- assert(Index == StrTabBuf.size());
+ assert(Index == StrTab.size());
StrTab.Size = Index;
// 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 = getSection(".symtab", ELFSection::SHT_SYMTAB, 0);
- SymTab.Align = is64Bit ? 8 : 4;
- SymTab.Link = StrTab.SectionIdx; // Section Index of .strtab.
- SymTab.Info = FirstNonLocalSymbol; // First non-STB_LOCAL symbol.
- SymTab.EntSize = is64Bit ? 24 : 16; // Size of each symtab entry.
- DataBuffer &SymTabBuf = SymTab.SectionData;
- OutputBuffer SymTabOut(SymTabBuf, is64Bit, isLittleEndian);
-
- if (!is64Bit) { // 32-bit and 64-bit formats are shuffled a bit.
- for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) {
- ELFSym &Sym = SymbolTable[i];
- SymTabOut.outword(Sym.NameIdx);
- SymTabOut.outaddr32(Sym.Value);
- SymTabOut.outword(Sym.Size);
- SymTabOut.outbyte(Sym.Info);
- SymTabOut.outbyte(Sym.Other);
- SymTabOut.outhalf(Sym.SectionIdx);
- }
- } else {
- for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) {
- ELFSym &Sym = SymbolTable[i];
- SymTabOut.outword(Sym.NameIdx);
- SymTabOut.outbyte(Sym.Info);
- SymTabOut.outbyte(Sym.Other);
- SymTabOut.outhalf(Sym.SectionIdx);
- SymTabOut.outaddr64(Sym.Value);
- SymTabOut.outxword(Sym.Size);
- }
- }
+ ELFSection &SymTab = getSymbolTableSection();
+ SymTab.Align = TEW->getSymTabAlignment();
+ SymTab.Link = StrTab.SectionIdx; // Section Index of .strtab.
+ SymTab.Info = FirstNonLocalSymbol; // First non-STB_LOCAL symbol.
+
+ // Size of each symtab entry.
+ SymTab.EntSize = TEW->getSymTabEntrySize();
+
+ for (unsigned i = 0, e = SymbolList.size(); i != e; ++i)
+ EmitSymbol(SymTab, SymbolList[i]);
- SymTab.Size = SymTabBuf.size();
+ SymTab.Size = SymTab.size();
}
/// EmitSectionTableStringTable - This method adds and emits a section for the
// Now that we know which section number is the .shstrtab section, update the
// e_shstrndx entry in the ELF header.
- OutputBuffer FHOut(FileHeader, is64Bit, isLittleEndian);
- FHOut.fixhalf(SHStrTab.SectionIdx, ELFHdr_e_shstrndx_Offset);
+ ElfHdr.fixWord16(SHStrTab.SectionIdx, ELFHdr_e_shstrndx_Offset);
// Set the NameIdx of each section in the string table and emit the bytes for
// the string table.
unsigned Index = 0;
- DataBuffer &Buf = SHStrTab.SectionData;
for (std::list<ELFSection>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++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;
-
- // Add the name to the output buffer, including the null terminator.
- Buf.insert(Buf.end(), I->Name.begin(), I->Name.end());
-
- // Add a null terminator.
- Buf.push_back(0);
+ SHStrTab.emitString(I->getName());
// Keep track of the number of bytes emitted to this section.
- Index += I->Name.size()+1;
+ Index += I->getName().size()+1;
}
// Set the size of .shstrtab now that we know what it is.
- assert(Index == Buf.size());
+ assert(Index == SHStrTab.size());
SHStrTab.Size = Index;
}
/// SectionTable.
void ELFWriter::OutputSectionsAndSectionTable() {
// Pass #1: Compute the file offset for each section.
- size_t FileOff = FileHeader.size(); // File header first.
+ size_t FileOff = ElfHdr.size(); // File header first.
- // Emit all of the section data in order.
+ // Adjust alignment of all section if needed.
for (std::list<ELFSection>::iterator I = SectionList.begin(),
E = SectionList.end(); I != E; ++I) {
if (!I->SectionIdx)
continue;
+ if (!I->size()) {
+ I->Offset = FileOff;
+ continue;
+ }
+
// Update Section size
if (!I->Size)
- I->Size = I->SectionData.size();
+ I->Size = I->size();
// Align FileOff to whatever the alignment restrictions of the section are.
if (I->Align)
// Now that we know where all of the sections will be emitted, set the e_shnum
// entry in the ELF header.
- OutputBuffer FHOut(FileHeader, is64Bit, isLittleEndian);
- FHOut.fixhalf(NumSections, ELFHdr_e_shnum_Offset);
+ ElfHdr.fixWord16(NumSections, ELFHdr_e_shnum_Offset);
// Now that we know the offset in the file of the section table, update the
// e_shoff address in the ELF header.
- FHOut.fixaddr(FileOff, ELFHdr_e_shoff_Offset);
+ ElfHdr.fixWord(FileOff, ELFHdr_e_shoff_Offset);
// Now that we know all of the data in the file header, emit it and all of the
// sections!
- O.write((char*)&FileHeader[0], FileHeader.size());
- FileOff = FileHeader.size();
- DataBuffer().swap(FileHeader);
+ O.write((char *)&ElfHdr.getData()[0], ElfHdr.size());
+ FileOff = ElfHdr.size();
- DataBuffer Table;
- OutputBuffer TableOut(Table, is64Bit, isLittleEndian);
+ // Section Header Table blob
+ BinaryObject SHdrTable(isLittleEndian, is64Bit);
- // Emit all of the section data and build the section table itself.
+ // Emit all of sections to the file and build the section header table.
while (!SectionList.empty()) {
- const ELFSection &S = *SectionList.begin();
+ ELFSection &S = *SectionList.begin();
+ 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)
+ if (S.Align) {
for (size_t NewFileOff = (FileOff+S.Align-1) & ~(S.Align-1);
- FileOff != NewFileOff; ++FileOff)
+ FileOff != NewFileOff; ++FileOff)
O << (char)0xAB;
- O.write((char*)&S.SectionData[0], S.Size);
-
- DOUT << "SectionIdx: " << S.SectionIdx << ", Name: " << S.Name
- << ", Size: " << S.Size << ", Offset: " << S.Offset << "\n";
-
- FileOff += S.Size;
+ }
- TableOut.outword(S.NameIdx); // sh_name - Symbol table name idx
- TableOut.outword(S.Type); // sh_type - Section contents & semantics
- TableOut.outaddr(S.Flags); // sh_flags - Section flags.
- TableOut.outaddr(S.Addr); // sh_addr - The mem addr this section is in.
- TableOut.outaddr(S.Offset); // sh_offset - Offset from the file start.
- TableOut.outaddr(S.Size); // sh_size - The section size.
- TableOut.outword(S.Link); // sh_link - Section header table index link.
- TableOut.outword(S.Info); // sh_info - Auxillary information.
- TableOut.outaddr(S.Align); // sh_addralign - Alignment of section.
- TableOut.outaddr(S.EntSize); // sh_entsize - Size of entries in the section
+ if (S.size()) {
+ O.write((char *)&S.getData()[0], S.Size);
+ FileOff += S.Size;
+ }
+ EmitSectionHeader(SHdrTable, S);
SectionList.pop_front();
}
O << (char)0xAB;
// Emit the section table itself.
- O.write((char*)&Table[0], Table.size());
+ O.write((char *)&SHdrTable.getData()[0], SHdrTable.size());
}