//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// #3. ".bss" entry - global variables without initializers. [ if needed ]
// ...
// #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!
//
//===----------------------------------------------------------------------===//
-#include "llvm/CodeGen/ELFWriter.h"
+#include "ELFWriter.h"
#include "llvm/Module.h"
+#include "llvm/PassManager.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 <list>
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,
+ std::ostream &O,
+ TargetMachine &TM) {
+ ELFWriter *EW = new ELFWriter(O, TM);
+ PM.add(EW);
+ return &EW->getMachineCodeEmitter();
+}
+
+//===----------------------------------------------------------------------===//
+// ELFCodeEmitter Implementation
+//===----------------------------------------------------------------------===//
+
namespace llvm {
+ /// ELFCodeEmitter - This class is used by the ELFWriter to emit the code for
+ /// functions to the ELF file.
class ELFCodeEmitter : public MachineCodeEmitter {
ELFWriter &EW;
- std::vector<unsigned char> &OutputBuffer;
+ TargetMachine &TM;
+ ELFWriter::ELFSection *ES; // Section to write to.
+ std::vector<unsigned char> *OutBuffer;
size_t FnStart;
public:
- ELFCodeEmitter(ELFWriter &ew) : EW(ew), OutputBuffer(EW.OutputBuffer) {}
-
- void startFunction(MachineFunction &F) {
- // Align the output buffer to the appropriate alignment.
- unsigned Align = 16; // FIXME: GENERICIZE!!
- ELFWriter::ELFSection &TextSection = EW.SectionList.back();
-
- // Upgrade the section alignment if required.
- if (TextSection.Align < Align) TextSection.Align = Align;
-
- // Add padding zeros to the end of the buffer to make sure that the
- // function will start on the correct byte alignment within the section.
- size_t SectionOff = OutputBuffer.size()-TextSection.Offset;
- if (SectionOff & (Align-1)) {
- // Add padding to get alignment to the correct place.
- size_t Pad = Align-(SectionOff & (Align-1));
- OutputBuffer.resize(OutputBuffer.size()+Pad);
- }
-
- FnStart = OutputBuffer.size();
- }
- void finishFunction(MachineFunction &F) {
- // We now know the size of the function, add a symbol to represent it.
- ELFWriter::ELFSym FnSym(F.getFunction());
-
- // Figure out the binding (linkage) of the symbol.
- switch (F.getFunction()->getLinkage()) {
- default:
- // appending linkage is illegal for functions.
- assert(0 && "Unknown linkage type!");
- case GlobalValue::ExternalLinkage:
- FnSym.SetBind(ELFWriter::ELFSym::STB_GLOBAL);
- break;
- case GlobalValue::LinkOnceLinkage:
- case GlobalValue::WeakLinkage:
- FnSym.SetBind(ELFWriter::ELFSym::STB_WEAK);
- break;
- case GlobalValue::InternalLinkage:
- FnSym.SetBind(ELFWriter::ELFSym::STB_LOCAL);
- break;
- }
-
- FnSym.SetType(ELFWriter::ELFSym::STT_FUNC);
- FnSym.SectionIdx = EW.SectionList.size()-1; // .text section.
- // Value = Offset from start of .text
- FnSym.Value = FnStart - EW.SectionList.back().Offset;
- FnSym.Size = OutputBuffer.size()-FnStart;
-
- // Finally, add it to the symtab.
- EW.SymbolTable.push_back(FnSym);
- }
+ explicit ELFCodeEmitter(ELFWriter &ew) : EW(ew), TM(EW.TM), OutBuffer(0) {}
- void emitConstantPool(MachineConstantPool *MCP) {
- if (MCP->isEmpty()) return;
- assert(0 && "unimp");
- }
- virtual void emitByte(unsigned char B) {
- OutputBuffer.push_back(B);
+ void startFunction(MachineFunction &F);
+ bool finishFunction(MachineFunction &F);
+
+ void addRelocation(const MachineRelocation &MR) {
+ assert(0 && "relo not handled yet!");
}
- virtual void emitWordAt(unsigned W, unsigned *Ptr) {
- assert(0 && "ni");
+
+ virtual void StartMachineBasicBlock(MachineBasicBlock *MBB) {
}
- virtual void emitWord(unsigned W) {
- assert(0 && "ni");
+
+ virtual intptr_t getConstantPoolEntryAddress(unsigned Index) const {
+ assert(0 && "CP not implementated yet!");
+ return 0;
}
- virtual uint64_t getCurrentPCValue() {
- return OutputBuffer.size();
+ virtual intptr_t getJumpTableEntryAddress(unsigned Index) const {
+ assert(0 && "JT not implementated yet!");
+ return 0;
}
- virtual uint64_t getCurrentPCOffset() {
- return OutputBuffer.size()-FnStart;
+
+ virtual intptr_t getMachineBasicBlockAddress(MachineBasicBlock *MBB) const {
+ assert(0 && "JT not implementated yet!");
+ return 0;
}
- void addRelocation(const MachineRelocation &MR) {
- assert(0 && "relo not handled yet!");
+
+ virtual intptr_t getLabelAddress(uint64_t Label) const {
+ assert(0 && "Label address not implementated yet!");
+ abort();
+ return 0;
}
- virtual uint64_t getConstantPoolEntryAddress(unsigned Index) {
- assert(0 && "CP not implementated yet!");
+
+ virtual void emitLabel(uint64_t LabelID) {
+ assert(0 && "emit Label not implementated yet!");
+ abort();
}
- /// JIT SPECIFIC FUNCTIONS
- void startFunctionStub(unsigned StubSize) {
+
+
+ virtual void setModuleInfo(llvm::MachineModuleInfo* MMI) { }
+
+
+ /// JIT SPECIFIC FUNCTIONS - DO NOT IMPLEMENT THESE HERE!
+ void startFunctionStub(const GlobalValue* F, unsigned StubSize,
+ unsigned Alignment = 1) {
assert(0 && "JIT specific function called!");
abort();
}
- void *finishFunctionStub(const Function *F) {
+ void *finishFunctionStub(const GlobalValue *F) {
assert(0 && "JIT specific function called!");
abort();
return 0;
};
}
+/// startFunction - This callback is invoked when a new machine function is
+/// about to be emitted.
+void ELFCodeEmitter::startFunction(MachineFunction &F) {
+ // Align the output buffer to the appropriate alignment.
+ unsigned Align = 16; // FIXME: GENERICIZE!!
+ // Get the ELF Section that this function belongs in.
+ ES = &EW.getSection(".text", ELFWriter::ELFSection::SHT_PROGBITS,
+ ELFWriter::ELFSection::SHF_EXECINSTR |
+ ELFWriter::ELFSection::SHF_ALLOC);
+ OutBuffer = &ES->SectionData;
+ cerr << "FIXME: This code needs to be updated for changes in the "
+ << "CodeEmitter interfaces. In particular, this should set "
+ << "BufferBegin/BufferEnd/CurBufferPtr, not deal with OutBuffer!";
+ abort();
+
+ // Upgrade the section alignment if required.
+ if (ES->Align < Align) ES->Align = Align;
+
+ // Add padding zeros to the end of the buffer to make sure that the
+ // function will start on the correct byte alignment within the section.
+ OutputBuffer OB(*OutBuffer,
+ TM.getTargetData()->getPointerSizeInBits() == 64,
+ TM.getTargetData()->isLittleEndian());
+ OB.align(Align);
+ FnStart = OutBuffer->size();
+}
+
+/// finishFunction - This callback is invoked after the function is completely
+/// finished.
+bool ELFCodeEmitter::finishFunction(MachineFunction &F) {
+ // We now know the size of the function, add a symbol to represent it.
+ ELFWriter::ELFSym FnSym(F.getFunction());
+
+ // Figure out the binding (linkage) of the symbol.
+ switch (F.getFunction()->getLinkage()) {
+ default:
+ // appending linkage is illegal for functions.
+ assert(0 && "Unknown linkage type!");
+ case GlobalValue::ExternalLinkage:
+ FnSym.SetBind(ELFWriter::ELFSym::STB_GLOBAL);
+ break;
+ case GlobalValue::LinkOnceLinkage:
+ case GlobalValue::WeakLinkage:
+ FnSym.SetBind(ELFWriter::ELFSym::STB_WEAK);
+ break;
+ case GlobalValue::InternalLinkage:
+ FnSym.SetBind(ELFWriter::ELFSym::STB_LOCAL);
+ break;
+ }
+
+ ES->Size = OutBuffer->size();
+
+ FnSym.SetType(ELFWriter::ELFSym::STT_FUNC);
+ FnSym.SectionIdx = ES->SectionIdx;
+ FnSym.Value = FnStart; // Value = Offset from start of Section.
+ FnSym.Size = OutBuffer->size()-FnStart;
+
+ // Finally, add it to the symtab.
+ EW.SymbolTable.push_back(FnSym);
+ return false;
+}
+
+//===----------------------------------------------------------------------===//
+// ELFWriter Implementation
+//===----------------------------------------------------------------------===//
-ELFWriter::ELFWriter(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) {
- e_machine = 0; // e_machine defaults to 'No Machine'
+ELFWriter::ELFWriter(std::ostream &o, TargetMachine &tm)
+ : MachineFunctionPass((intptr_t)&ID), O(o), TM(tm) {
e_flags = 0; // e_flags defaults to 0, no flags.
- is64Bit = TM.getTargetData().getPointerSizeInBits() == 64;
- isLittleEndian = TM.getTargetData().isLittleEndian();
+ is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64;
+ isLittleEndian = TM.getTargetData()->isLittleEndian();
// Create the machine code emitter object for this target.
MCE = new ELFCodeEmitter(*this);
+ NumSections = 0;
}
ELFWriter::~ELFWriter() {
bool ELFWriter::doInitialization(Module &M) {
Mang = new Mangler(M);
- outbyte(0x7F); // EI_MAG0
- outbyte('E'); // EI_MAG1
- outbyte('L'); // EI_MAG2
- outbyte('F'); // EI_MAG3
- outbyte(is64Bit ? 2 : 1); // EI_CLASS
- outbyte(isLittleEndian ? 1 : 2); // EI_DATA
- outbyte(1); // EI_VERSION
- for (unsigned i = OutputBuffer.size(); i != 16; ++i)
- outbyte(0); // EI_PAD up to 16 bytes.
-
+ // Local alias to shortenify coming code.
+ std::vector<unsigned char> &FH = FileHeader;
+ OutputBuffer FHOut(FH, is64Bit, isLittleEndian);
+
+ FHOut.outbyte(0x7F); // EI_MAG0
+ FHOut.outbyte('E'); // EI_MAG1
+ FHOut.outbyte('L'); // EI_MAG2
+ FHOut.outbyte('F'); // EI_MAG3
+ FHOut.outbyte(is64Bit ? 2 : 1); // EI_CLASS
+ FHOut.outbyte(isLittleEndian ? 1 : 2); // EI_DATA
+ FHOut.outbyte(1); // EI_VERSION
+ FH.resize(16); // EI_PAD up to 16 bytes.
+
// This should change for shared objects.
- outhalf(1); // e_type = ET_REL
- outhalf(e_machine); // e_machine = whatever the target wants
- outword(1); // e_version = 1
- outaddr(0); // e_entry = 0 -> no entry point in .o file
- outaddr(0); // e_phoff = 0 -> no program header for .o
-
- ELFHeader_e_shoff_Offset = OutputBuffer.size();
- outaddr(0); // e_shoff
- outword(e_flags); // e_flags = whatever the target wants
-
- assert(!is64Bit && "These sizes need to be adjusted for 64-bit!");
- outhalf(52); // e_ehsize = ELF header size
- outhalf(0); // e_phentsize = prog header entry size
- outhalf(0); // e_phnum = # prog header entries = 0
- outhalf(40); // e_shentsize = sect header entry size
-
-
- ELFHeader_e_shnum_Offset = OutputBuffer.size();
- outhalf(0); // e_shnum = # of section header ents
- ELFHeader_e_shstrndx_Offset = OutputBuffer.size();
- outhalf(0); // e_shstrndx = Section # of '.shstrtab'
-
- // Add the null section.
- SectionList.push_back(ELFSection());
+ FHOut.outhalf(1); // e_type = ET_REL
+ FHOut.outword(TM.getELFWriterInfo()->getEMachine()); // target-defined
+ FHOut.outword(1); // e_version = 1
+ FHOut.outaddr(0); // e_entry = 0 -> no entry point in .o file
+ FHOut.outaddr(0); // e_phoff = 0 -> no program header for .o
+
+ ELFHeader_e_shoff_Offset = FH.size();
+ FHOut.outaddr(0); // e_shoff
+ FHOut.outword(e_flags); // e_flags = whatever the target wants
+
+ FHOut.outhalf(is64Bit ? 64 : 52); // e_ehsize = ELF header size
+ FHOut.outhalf(0); // e_phentsize = prog header entry size
+ FHOut.outhalf(0); // e_phnum = # prog header entries = 0
+ FHOut.outhalf(is64Bit ? 64 : 40); // e_shentsize = sect hdr entry size
+
+
+ ELFHeader_e_shnum_Offset = FH.size();
+ FHOut.outhalf(0); // e_shnum = # of section header ents
+ ELFHeader_e_shstrndx_Offset = FH.size();
+ FHOut.outhalf(0); // e_shstrndx = Section # of '.shstrtab'
+
+ // Add the null section, which is required to be first in the file.
+ getSection("", 0, 0);
// Start up the symbol table. The first entry in the symtab is the null
// entry.
SymbolTable.push_back(ELFSym(0));
- SectionList.push_back(ELFSection(".text", OutputBuffer.size()));
-
return false;
}
-void ELFWriter::EmitGlobal(GlobalVariable *GV, ELFSection &DataSection,
- ELFSection &BSSSection) {
+void ELFWriter::EmitGlobal(GlobalVariable *GV) {
// 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.
SymbolTable.push_back(ExternalSym);
return;
}
-
+
const Type *GVType = (const Type*)GV->getType();
- unsigned Align = TM.getTargetData().getTypeAlignment(GVType);
- unsigned Size = TM.getTargetData().getTypeSize(GVType);
+ unsigned Align = TM.getTargetData()->getPreferredAlignment(GV);
+ unsigned Size = TM.getTargetData()->getABITypeSize(GVType);
// If this global has a zero initializer, it is part of the .bss or common
// section.
// 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
}
// Set the idx of the .bss section
- BSSSym.SectionIdx = &BSSSection-&SectionList[0];
+ BSSSym.SectionIdx = BSSSection.SectionIdx;
SymbolTable.push_back(BSSSym);
// Reserve space in the .bss section for this symbol.
/// doFinalization - Now that the module has been completely processed, emit
/// the ELF file to 'O'.
bool ELFWriter::doFinalization(Module &M) {
- // Okay, the .text section has now been finalized. If it contains nothing, do
- // not emit it.
- uint64_t TextSize = OutputBuffer.size() - SectionList.back().Offset;
- if (TextSize == 0) {
- SectionList.pop_back();
- } else {
- ELFSection &Text = SectionList.back();
- Text.Size = TextSize;
- Text.Type = ELFSection::SHT_PROGBITS;
- Text.Flags = ELFSection::SHF_EXECINSTR | ELFSection::SHF_ALLOC;
- }
-
// Okay, the ELF header and .text sections have been completed, build the
// .data, .bss, and "common" sections next.
- SectionList.push_back(ELFSection(".data", OutputBuffer.size()));
- SectionList.push_back(ELFSection(".bss"));
- ELFSection &DataSection = *(SectionList.end()-2);
- ELFSection &BSSSection = SectionList.back();
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
- EmitGlobal(I, DataSection, BSSSection);
-
- // Finish up the data section.
- DataSection.Type = ELFSection::SHT_PROGBITS;
- DataSection.Flags = ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC;
-
- // The BSS Section logically starts at the end of the Data Section (adjusted
- // to the required alignment of the BSSSection).
- BSSSection.Offset = DataSection.Offset+DataSection.Size;
- BSSSection.Type = ELFSection::SHT_NOBITS;
- BSSSection.Flags = ELFSection::SHF_WRITE | ELFSection::SHF_ALLOC;
- if (BSSSection.Align)
- BSSSection.Offset = (BSSSection.Offset+BSSSection.Align-1) &
- ~(BSSSection.Align-1);
+ EmitGlobal(I);
// Emit the symbol table now, if non-empty.
EmitSymbolTable();
// Emit the string table for the sections in the ELF file we have.
EmitSectionTableStringTable();
- // Emit the .o file section table.
- EmitSectionTable();
-
- // Emit the .o file to the specified stream.
- O.write((char*)&OutputBuffer[0], OutputBuffer.size());
+ // Emit the sections to the .o file, and emit the section table for the file.
+ OutputSectionsAndSectionTable();
- // Free the output buffer.
- std::vector<unsigned char>().swap(OutputBuffer);
+ // We are done with the abstract symbols.
+ SectionList.clear();
+ NumSections = 0;
// Release the name mangler object.
delete Mang; Mang = 0;
// FIXME: compact all local symbols to the start of the symtab.
unsigned FirstNonLocalSymbol = 1;
- SectionList.push_back(ELFSection(".strtab", OutputBuffer.size()));
- ELFSection &StrTab = SectionList.back();
- StrTab.Type = ELFSection::SHT_STRTAB;
+ ELFSection &StrTab = getSection(".strtab", ELFSection::SHT_STRTAB, 0);
StrTab.Align = 1;
+ DataBuffer &StrTabBuf = StrTab.SectionData;
+ OutputBuffer StrTabOut(StrTabBuf, is64Bit, isLittleEndian);
+
// Set the zero'th symbol to a null byte, as required.
- outbyte(0);
+ StrTabOut.outbyte(0);
SymbolTable[0].NameIdx = 0;
unsigned Index = 1;
for (unsigned i = 1, e = SymbolTable.size(); i != e; ++i) {
SymbolTable[i].NameIdx = Index;
// Add the name to the output buffer, including the null terminator.
- OutputBuffer.insert(OutputBuffer.end(), Name.begin(), Name.end());
+ StrTabBuf.insert(StrTabBuf.end(), Name.begin(), Name.end());
// Add a null terminator.
- OutputBuffer.push_back(0);
+ StrTabBuf.push_back(0);
// Keep track of the number of bytes emitted to this section.
Index += Name.size()+1;
}
}
-
- StrTab.Size = OutputBuffer.size()-StrTab.Offset;
+ assert(Index == StrTabBuf.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.
- assert(!is64Bit && "Should this be 8 byte aligned for 64-bit?"
- " (check .Align below also)");
- align(4);
-
- SectionList.push_back(ELFSection(".symtab", OutputBuffer.size()));
- ELFSection &SymTab = SectionList.back();
- SymTab.Type = ELFSection::SHT_SYMTAB;
- SymTab.Align = 4; // FIXME: check for ELF64
- SymTab.Link = SectionList.size()-2; // Section Index of .strtab.
+ ELFSection &SymTab = getSection(".symtab", ELFSection::SHT_SYMTAB, 0);
+ SymTab.Align = is64Bit ? 8 : 4;
+ SymTab.Link = SymTab.SectionIdx; // Section Index of .strtab.
SymTab.Info = FirstNonLocalSymbol; // First non-STB_LOCAL symbol.
SymTab.EntSize = 16; // Size of each symtab entry. FIXME: wrong for ELF64
-
- assert(!is64Bit && "check this!");
- for (unsigned i = 0, e = SymbolTable.size(); i != e; ++i) {
- ELFSym &Sym = SymbolTable[i];
- outword(Sym.NameIdx);
- outaddr(Sym.Value);
- outword(Sym.Size);
- outbyte(Sym.Info);
- outbyte(Sym.Other);
- outhalf(Sym.SectionIdx);
+ 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);
+ }
}
- SymTab.Size = OutputBuffer.size()-SymTab.Offset;
+ SymTab.Size = SymTabBuf.size();
}
/// EmitSectionTableStringTable - This method adds and emits a section for the
/// section names.
void ELFWriter::EmitSectionTableStringTable() {
// First step: add the section for the string table to the list of sections:
- SectionList.push_back(ELFSection(".shstrtab", OutputBuffer.size()));
- SectionList.back().Type = ELFSection::SHT_STRTAB;
+ ELFSection &SHStrTab = getSection(".shstrtab", ELFSection::SHT_STRTAB, 0);
// Now that we know which section number is the .shstrtab section, update the
// e_shstrndx entry in the ELF header.
- fixhalf(SectionList.size()-1, ELFHeader_e_shstrndx_Offset);
+ OutputBuffer FHOut(FileHeader, is64Bit, isLittleEndian);
+ FHOut.fixhalf(SHStrTab.SectionIdx, ELFHeader_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 (unsigned i = 0, e = SectionList.size(); i != e; ++i) {
+ 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.
- SectionList[i].NameIdx = Index;
+ I->NameIdx = Index;
// Add the name to the output buffer, including the null terminator.
- OutputBuffer.insert(OutputBuffer.end(), SectionList[i].Name.begin(),
- SectionList[i].Name.end());
+ Buf.insert(Buf.end(), I->Name.begin(), I->Name.end());
+
// Add a null terminator.
- OutputBuffer.push_back(0);
+ Buf.push_back(0);
// Keep track of the number of bytes emitted to this section.
- Index += SectionList[i].Name.size()+1;
+ Index += I->Name.size()+1;
}
// Set the size of .shstrtab now that we know what it is.
- SectionList.back().Size = Index;
+ assert(Index == Buf.size());
+ SHStrTab.Size = Index;
}
-/// EmitSectionTable - Now that we have emitted the entire contents of the file
-/// (all of the sections), emit the section table which informs the reader where
-/// the boundaries are.
-void ELFWriter::EmitSectionTable() {
- // Now that all of the sections have been emitted, set the e_shnum entry in
- // the ELF header.
- fixhalf(SectionList.size(), ELFHeader_e_shnum_Offset);
-
- // Now that we know the offset in the file of the section table (which we emit
- // next), update the e_shoff address in the ELF header.
- fixaddr(OutputBuffer.size(), ELFHeader_e_shoff_Offset);
-
- // Emit all of the section table entries.
- for (unsigned i = 0, e = SectionList.size(); i != e; ++i) {
- const ELFSection &S = SectionList[i];
- outword(S.NameIdx); // sh_name - Symbol table name idx
- outword(S.Type); // sh_type - Section contents & semantics
- outword(S.Flags); // sh_flags - Section flags.
- outaddr(S.Addr); // sh_addr - The mem address this section appears in.
- outaddr(S.Offset); // sh_offset - The offset from the start of the file.
- outword(S.Size); // sh_size - The section size.
- outword(S.Link); // sh_link - Section header table index link.
- outword(S.Info); // sh_info - Auxillary information.
- outword(S.Align); // sh_addralign - Alignment of section.
- outword(S.EntSize); // sh_entsize - Size of each entry in the section.
+/// OutputSectionsAndSectionTable - Now that we have constructed the file header
+/// and all of the sections, emit these to the ostream destination and emit the
+/// SectionTable.
+void ELFWriter::OutputSectionsAndSectionTable() {
+ // Pass #1: Compute the file offset for each section.
+ size_t FileOff = FileHeader.size(); // File header first.
+
+ // Emit all of the section data in order.
+ for (std::list<ELFSection>::iterator I = SectionList.begin(),
+ E = SectionList.end(); I != E; ++I) {
+ // Align FileOff to whatever the alignment restrictions of the section are.
+ if (I->Align)
+ FileOff = (FileOff+I->Align-1) & ~(I->Align-1);
+ I->Offset = FileOff;
+ FileOff += I->SectionData.size();
+ }
+
+ // Align Section Header.
+ unsigned TableAlign = is64Bit ? 8 : 4;
+ FileOff = (FileOff+TableAlign-1) & ~(TableAlign-1);
+
+ // 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, ELFHeader_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, ELFHeader_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);
+
+ DataBuffer Table;
+ OutputBuffer TableOut(Table, is64Bit, isLittleEndian);
+
+ // Emit all of the section data and build the section table itself.
+ while (!SectionList.empty()) {
+ const ELFSection &S = *SectionList.begin();
+
+ // 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.put((char)0xAB);
+ O.write((char*)&S.SectionData[0], S.SectionData.size());
+ FileOff += S.SectionData.size();
+
+ TableOut.outword(S.NameIdx); // sh_name - Symbol table name idx
+ TableOut.outword(S.Type); // sh_type - Section contents & semantics
+ TableOut.outword(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.outword(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.outword(S.Align); // sh_addralign - Alignment of section.
+ TableOut.outword(S.EntSize); // sh_entsize - Size of entries in the section
+
+ SectionList.pop_front();
}
- // Release the memory allocated for the section list.
- std::vector<ELFSection>().swap(SectionList);
+ // Align output for the section table.
+ for (size_t NewFileOff = (FileOff+TableAlign-1) & ~(TableAlign-1);
+ FileOff != NewFileOff; ++FileOff)
+ O.put((char)0xAB);
+
+ // Emit the section table itself.
+ O.write((char*)&Table[0], Table.size());
}