+++ /dev/null
-//===-- ELFWriter.cpp - Target-independent ELF Writer code ----------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements the target-independent ELF writer. This file writes out
-// the ELF file in the following order:
-//
-// #1. ELF Header
-// #2. '.text' section
-// #3. '.data' section
-// #4. '.bss' section (conceptual position in file)
-// ...
-// #X. '.shstrtab' section
-// #Y. Section Table
-//
-// The entries in the section table are laid out as:
-// #0. Null entry [required]
-// #1. ".text" entry - the program code
-// #2. ".data" entry - global variables with initializers. [ if needed ]
-// #3. ".bss" entry - global variables without initializers. [ if needed ]
-// ...
-// #N. ".shstrtab" entry - String table for the section names.
-//
-//===----------------------------------------------------------------------===//
-
-#define DEBUG_TYPE "elfwriter"
-#include "ELF.h"
-#include "ELFWriter.h"
-#include "ELFCodeEmitter.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/MachineCodeEmitter.h"
-#include "llvm/CodeGen/ObjectCodeEmitter.h"
-#include "llvm/CodeGen/MachineCodeEmitter.h"
-#include "llvm/CodeGen/MachineConstantPool.h"
-#include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCSectionELF.h"
-#include "llvm/MC/MCAsmInfo.h"
-#include "llvm/Target/Mangler.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetELFWriterInfo.h"
-#include "llvm/Target/TargetLowering.h"
-#include "llvm/Target/TargetLoweringObjectFile.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetRegisterInfo.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/raw_ostream.h"
-#include "llvm/ADT/SmallString.h"
-using namespace llvm;
-
-char ELFWriter::ID = 0;
-
-//===----------------------------------------------------------------------===//
-// ELFWriter Implementation
-//===----------------------------------------------------------------------===//
-
-ELFWriter::ELFWriter(raw_ostream &o, TargetMachine &tm)
- : MachineFunctionPass(ID), O(o), TM(tm),
- OutContext(*new MCContext(*TM.getMCAsmInfo(), *TM.getRegisterInfo(),
- &TM.getTargetLowering()->getObjFileLowering())),
- TLOF(TM.getTargetLowering()->getObjFileLowering()),
- is64Bit(TM.getTargetData()->getPointerSizeInBits() == 64),
- isLittleEndian(TM.getTargetData()->isLittleEndian()),
- ElfHdr(isLittleEndian, is64Bit) {
-
- MAI = TM.getMCAsmInfo();
- TEW = TM.getELFWriterInfo();
-
- // Create the object code emitter object for this target.
- ElfCE = new ELFCodeEmitter(*this);
-
- // Initial number of sections
- NumSections = 0;
-}
-
-ELFWriter::~ELFWriter() {
- delete ElfCE;
- delete &OutContext;
-
- while(!SymbolList.empty()) {
- delete SymbolList.back();
- SymbolList.pop_back();
- }
-
- while(!PrivateSyms.empty()) {
- delete PrivateSyms.back();
- PrivateSyms.pop_back();
- }
-
- while(!SectionList.empty()) {
- delete SectionList.back();
- SectionList.pop_back();
- }
-
- // Release the name mangler object.
- delete Mang; Mang = 0;
-}
-
-// doInitialization - Emit the file header and all of the global variables for
-// the module to the ELF file.
-bool ELFWriter::doInitialization(Module &M) {
- // Initialize TargetLoweringObjectFile.
- const_cast<TargetLoweringObjectFile&>(TLOF).Initialize(OutContext, TM);
-
- Mang = new Mangler(OutContext, *TM.getTargetData());
-
- // ELF Header
- // ----------
- // Fields e_shnum e_shstrndx are only known after all section have
- // been emitted. They locations in the ouput buffer are recorded so
- // to be patched up later.
- //
- // Note
- // ----
- // 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
-
- 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(ELF::EV_CURRENT); // e_ident[EI_VERSION]
- ElfHdr.emitAlignment(16); // e_ident[EI_NIDENT-EI_PAD]
-
- ElfHdr.emitWord16(ELF::ET_REL); // e_type
- ElfHdr.emitWord16(TEW->getEMachine()); // e_machine = target
- ElfHdr.emitWord32(ELF::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
- ElfHdr.emitWord16(TEW->getSHdrSize());
-
- // e_shnum = # of section header ents
- ELFHdr_e_shnum_Offset = ElfHdr.size();
- ElfHdr.emitWord16(0); // Placeholder
-
- // e_shstrndx = Section # of '.shstrtab'
- ELFHdr_e_shstrndx_Offset = ElfHdr.size();
- ElfHdr.emitWord16(0); // Placeholder
-
- // Add the null section, which is required to be first in the file.
- getNullSection();
-
- // The first entry in the symtab is the null symbol and the second
- // is a local symbol containing the module/file name
- SymbolList.push_back(new ELFSym());
- SymbolList.push_back(ELFSym::getFileSym());
-
- return false;
-}
-
-// AddPendingGlobalSymbol - Add a global to be processed and to
-// the global symbol lookup, use a zero index because the table
-// index will be determined later.
-void ELFWriter::AddPendingGlobalSymbol(const GlobalValue *GV,
- bool AddToLookup /* = false */) {
- PendingGlobals.insert(GV);
- if (AddToLookup)
- GblSymLookup[GV] = 0;
-}
-
-// AddPendingExternalSymbol - Add the external to be processed
-// and to the external symbol lookup, use a zero index because
-// the symbol table index will be determined later.
-void ELFWriter::AddPendingExternalSymbol(const char *External) {
- PendingExternals.insert(External);
- ExtSymLookup[External] = 0;
-}
-
-ELFSection &ELFWriter::getDataSection() {
- const MCSectionELF *Data = (const MCSectionELF *)TLOF.getDataSection();
- return getSection(Data->getSectionName(), Data->getType(),
- Data->getFlags(), 4);
-}
-
-ELFSection &ELFWriter::getBSSSection() {
- const MCSectionELF *BSS = (const MCSectionELF *)TLOF.getBSSSection();
- return getSection(BSS->getSectionName(), BSS->getType(), BSS->getFlags(), 4);
-}
-
-// getCtorSection - Get the static constructor section
-ELFSection &ELFWriter::getCtorSection() {
- const MCSectionELF *Ctor = (const MCSectionELF *)TLOF.getStaticCtorSection();
- return getSection(Ctor->getSectionName(), Ctor->getType(), Ctor->getFlags());
-}
-
-// getDtorSection - Get the static destructor section
-ELFSection &ELFWriter::getDtorSection() {
- const MCSectionELF *Dtor = (const MCSectionELF *)TLOF.getStaticDtorSection();
- return getSection(Dtor->getSectionName(), Dtor->getType(), Dtor->getFlags());
-}
-
-// getTextSection - Get the text section for the specified function
-ELFSection &ELFWriter::getTextSection(const Function *F) {
- const MCSectionELF *Text =
- (const MCSectionELF *)TLOF.SectionForGlobal(F, Mang, TM);
- return getSection(Text->getSectionName(), Text->getType(), Text->getFlags());
-}
-
-// getJumpTableSection - Get a read only section for constants when
-// emitting jump tables. TODO: add PIC support
-ELFSection &ELFWriter::getJumpTableSection() {
- const MCSectionELF *JT =
- (const MCSectionELF *)TLOF.getSectionForConstant(SectionKind::getReadOnly());
- return getSection(JT->getSectionName(), JT->getType(), JT->getFlags(),
- TM.getTargetData()->getPointerABIAlignment());
-}
-
-// getConstantPoolSection - Get a constant pool section based on the machine
-// constant pool entry type and relocation info.
-ELFSection &ELFWriter::getConstantPoolSection(MachineConstantPoolEntry &CPE) {
- SectionKind Kind;
- switch (CPE.getRelocationInfo()) {
- default: llvm_unreachable("Unknown section kind");
- case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
- case 1:
- Kind = SectionKind::getReadOnlyWithRelLocal();
- break;
- case 0:
- switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
- case 4: Kind = SectionKind::getMergeableConst4(); break;
- case 8: Kind = SectionKind::getMergeableConst8(); break;
- case 16: Kind = SectionKind::getMergeableConst16(); break;
- default: Kind = SectionKind::getMergeableConst(); break;
- }
- }
-
- const MCSectionELF *CPSect =
- (const MCSectionELF *)TLOF.getSectionForConstant(Kind);
- return getSection(CPSect->getSectionName(), CPSect->getType(),
- CPSect->getFlags(), CPE.getAlignment());
-}
-
-// getRelocSection - Return the relocation section of section 'S'. 'RelA'
-// is true if the relocation section contains entries with addends.
-ELFSection &ELFWriter::getRelocSection(ELFSection &S) {
- unsigned SectionType = TEW->hasRelocationAddend() ?
- ELF::SHT_RELA : ELF::SHT_REL;
-
- std::string SectionName(".rel");
- if (TEW->hasRelocationAddend())
- SectionName.append("a");
- SectionName.append(S.getName());
-
- return getSection(SectionName, SectionType, 0, TEW->getPrefELFAlignment());
-}
-
-// 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 ELF::STV_DEFAULT;
- case GlobalValue::HiddenVisibility:
- return ELF::STV_HIDDEN;
- case GlobalValue::ProtectedVisibility:
- return ELF::STV_PROTECTED;
- }
- return 0;
-}
-
-// getGlobalELFBinding - Returns the ELF specific binding type
-unsigned ELFWriter::getGlobalELFBinding(const GlobalValue *GV) {
- if (GV->hasInternalLinkage())
- return ELF::STB_LOCAL;
-
- if (GV->isWeakForLinker() && !GV->hasCommonLinkage())
- return ELF::STB_WEAK;
-
- return ELF::STB_GLOBAL;
-}
-
-// getGlobalELFType - Returns the ELF specific type for a global
-unsigned ELFWriter::getGlobalELFType(const GlobalValue *GV) {
- if (GV->isDeclaration())
- return ELF::STT_NOTYPE;
-
- if (isa<Function>(GV))
- return ELF::STT_FUNC;
-
- return ELF::STT_OBJECT;
-}
-
-// IsELFUndefSym - True if the global value must be marked as a symbol
-// which points to a SHN_UNDEF section. This means that the symbol has
-// no definition on the module.
-static bool IsELFUndefSym(const GlobalValue *GV) {
- return GV->isDeclaration() || (isa<Function>(GV));
-}
-
-// AddToSymbolList - Update the symbol lookup and If the symbol is
-// private add it to PrivateSyms list, otherwise to SymbolList.
-void ELFWriter::AddToSymbolList(ELFSym *GblSym) {
- assert(GblSym->isGlobalValue() && "Symbol must be a global value");
-
- const GlobalValue *GV = GblSym->getGlobalValue();
- if (GV->hasPrivateLinkage()) {
- // For a private symbols, keep track of the index inside
- // the private list since it will never go to the symbol
- // table and won't be patched up later.
- PrivateSyms.push_back(GblSym);
- GblSymLookup[GV] = PrivateSyms.size()-1;
- } else {
- // Non private symbol are left with zero indices until
- // they are patched up during the symbol table emition
- // (where the indicies are created).
- SymbolList.push_back(GblSym);
- GblSymLookup[GV] = 0;
- }
-}
-
-/// HasCommonSymbols - True if this section holds common symbols, this is
-/// indicated on the ELF object file by a symbol with SHN_COMMON section
-/// header index.
-static bool HasCommonSymbols(const MCSectionELF &S) {
- // FIXME: this is wrong, a common symbol can be in .data for example.
- if (StringRef(S.getSectionName()).startswith(".gnu.linkonce."))
- return true;
-
- return false;
-}
-
-
-// EmitGlobal - Choose the right section for global and emit it
-void ELFWriter::EmitGlobal(const GlobalValue *GV) {
-
- // Check if the referenced symbol is already emitted
- if (GblSymLookup.find(GV) != GblSymLookup.end())
- return;
-
- // Handle ELF Bind, Visibility and Type for the current symbol
- unsigned SymBind = getGlobalELFBinding(GV);
- unsigned SymType = getGlobalELFType(GV);
- bool IsUndefSym = IsELFUndefSym(GV);
-
- ELFSym *GblSym = IsUndefSym ? ELFSym::getUndefGV(GV, SymBind)
- : ELFSym::getGV(GV, SymBind, SymType, getGlobalELFVisibility(GV));
-
- if (!IsUndefSym) {
- assert(isa<GlobalVariable>(GV) && "GV not a global variable!");
- const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
-
- // Handle special llvm globals
- if (EmitSpecialLLVMGlobal(GVar))
- return;
-
- // Get the ELF section where this global belongs from TLOF
- const MCSectionELF *S =
- (const MCSectionELF *)TLOF.SectionForGlobal(GV, Mang, TM);
- ELFSection &ES =
- getSection(S->getSectionName(), S->getType(), S->getFlags());
- SectionKind Kind = S->getKind();
-
- // 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 (HasCommonSymbols(*S)) { // Symbol must go to a common section
- GblSym->SectionIdx = ELF::SHN_COMMON;
-
- // 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.
- ES.Align = 1;
- GblSym->Value = Align;
-
- } else if (Kind.isBSS() || Kind.isThreadBSS()) { // Symbol goes to BSS.
- 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 { // The symbol must go to some kind of data section
- 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);
- ES.emitAlignment(Align);
- GblSym->Value = ES.size();
-
- // Emit the global to the data section 'ES'
- EmitGlobalConstant(GVar->getInitializer(), ES);
- }
- }
-
- AddToSymbolList(GblSym);
-}
-
-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.
- GblS.emitZeros(padSize);
- }
- 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)) {
- for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
- EmitGlobalConstant(CVA->getOperand(i), GblS);
- return;
- } else if (isa<ConstantAggregateZero>(CV)) {
- GblS.emitZeros(Size);
- return;
- } else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
- EmitGlobalConstantStruct(CVS, GblS);
- return;
- } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
- APInt Val = CFP->getValueAPF().bitcastToAPInt();
- if (CFP->getType()->isDoubleTy())
- GblS.emitWord64(Val.getZExtValue());
- else if (CFP->getType()->isFloatTy())
- GblS.emitWord32(Val.getZExtValue());
- else if (CFP->getType()->isX86_FP80Ty()) {
- unsigned PadSize = TD->getTypeAllocSize(CFP->getType())-
- TD->getTypeStoreSize(CFP->getType());
- GblS.emitWordFP80(Val.getRawData(), PadSize);
- } else if (CFP->getType()->isPPC_FP128Ty())
- llvm_unreachable("PPC_FP128Ty global emission not implemented");
- return;
- } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
- if (Size == 1)
- GblS.emitByte(CI->getZExtValue());
- else if (Size == 2)
- GblS.emitWord16(CI->getZExtValue());
- else if (Size == 4)
- GblS.emitWord32(CI->getZExtValue());
- else
- EmitGlobalConstantLargeInt(CI, GblS);
- return;
- } else if (const ConstantVector *CP = dyn_cast<ConstantVector>(CV)) {
- VectorType *PTy = CP->getType();
- for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
- EmitGlobalConstant(CP->getOperand(I), GblS);
- return;
- } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
- // Resolve a constant expression which returns a (Constant, Offset)
- // pair. If 'Res.first' is a GlobalValue, emit a relocation with
- // the offset 'Res.second', otherwise emit a global constant like
- // it is always done for not contant expression types.
- CstExprResTy Res = ResolveConstantExpr(CE);
- const Constant *Op = Res.first;
-
- if (isa<GlobalValue>(Op))
- EmitGlobalDataRelocation(cast<const GlobalValue>(Op),
- TD->getTypeAllocSize(Op->getType()),
- GblS, Res.second);
- else
- EmitGlobalConstant(Op, GblS);
-
- return;
- } else if (CV->getType()->getTypeID() == Type::PointerTyID) {
- // Fill the data entry with zeros or emit a relocation entry
- if (isa<ConstantPointerNull>(CV))
- GblS.emitZeros(Size);
- else
- EmitGlobalDataRelocation(cast<const GlobalValue>(CV),
- Size, GblS);
- return;
- } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) {
- // This is a constant address for a global variable or function and
- // therefore must be referenced using a relocation entry.
- EmitGlobalDataRelocation(GV, Size, GblS);
- return;
- }
-
- std::string msg;
- raw_string_ostream ErrorMsg(msg);
- ErrorMsg << "Constant unimp for type: " << *CV->getType();
- report_fatal_error(ErrorMsg.str());
-}
-
-// ResolveConstantExpr - Resolve the constant expression until it stop
-// yielding other constant expressions.
-CstExprResTy ELFWriter::ResolveConstantExpr(const Constant *CV) {
- const TargetData *TD = TM.getTargetData();
-
- // There ins't constant expression inside others anymore
- if (!isa<ConstantExpr>(CV))
- return std::make_pair(CV, 0);
-
- const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
- switch (CE->getOpcode()) {
- case Instruction::BitCast:
- return ResolveConstantExpr(CE->getOperand(0));
-
- case Instruction::GetElementPtr: {
- const Constant *ptrVal = CE->getOperand(0);
- SmallVector<Value*, 8> idxVec(CE->op_begin()+1, CE->op_end());
- int64_t Offset = TD->getIndexedOffset(ptrVal->getType(), idxVec);
- return std::make_pair(ptrVal, Offset);
- }
- case Instruction::IntToPtr: {
- Constant *Op = CE->getOperand(0);
- Op = ConstantExpr::getIntegerCast(Op, TD->getIntPtrType(CV->getContext()),
- false/*ZExt*/);
- return ResolveConstantExpr(Op);
- }
- case Instruction::PtrToInt: {
- Constant *Op = CE->getOperand(0);
- Type *Ty = CE->getType();
-
- // We can emit the pointer value into this slot if the slot is an
- // integer slot greater or equal to the size of the pointer.
- if (TD->getTypeAllocSize(Ty) == TD->getTypeAllocSize(Op->getType()))
- return ResolveConstantExpr(Op);
-
- llvm_unreachable("Integer size less then pointer size");
- }
- case Instruction::Add:
- case Instruction::Sub: {
- // Only handle cases where there's a constant expression with GlobalValue
- // as first operand and ConstantInt as second, which are the cases we can
- // solve direclty using a relocation entry. GlobalValue=Op0, CstInt=Op1
- // 1) Instruction::Add => (global) + CstInt
- // 2) Instruction::Sub => (global) + -CstInt
- const Constant *Op0 = CE->getOperand(0);
- const Constant *Op1 = CE->getOperand(1);
- assert(isa<ConstantInt>(Op1) && "Op1 must be a ConstantInt");
-
- CstExprResTy Res = ResolveConstantExpr(Op0);
- assert(isa<GlobalValue>(Res.first) && "Op0 must be a GlobalValue");
-
- const APInt &RHS = cast<ConstantInt>(Op1)->getValue();
- switch (CE->getOpcode()) {
- case Instruction::Add:
- return std::make_pair(Res.first, RHS.getSExtValue());
- case Instruction::Sub:
- return std::make_pair(Res.first, (-RHS).getSExtValue());
- }
- }
- }
-
- report_fatal_error(CE->getOpcodeName() +
- StringRef(": Unsupported ConstantExpr type"));
-
- return std::make_pair(CV, 0); // silence warning
-}
-
-void ELFWriter::EmitGlobalDataRelocation(const GlobalValue *GV, unsigned Size,
- ELFSection &GblS, int64_t Offset) {
- // Create the relocation entry for the global value
- MachineRelocation MR =
- MachineRelocation::getGV(GblS.getCurrentPCOffset(),
- TEW->getAbsoluteLabelMachineRelTy(),
- const_cast<GlobalValue*>(GV),
- Offset);
-
- // Fill the data entry with zeros
- GblS.emitZeros(Size);
-
- // Add the relocation entry for the current data section
- GblS.addRelocation(MR);
-}
-
-void ELFWriter::EmitGlobalConstantLargeInt(const ConstantInt *CI,
- ELFSection &S) {
- const TargetData *TD = TM.getTargetData();
- unsigned BitWidth = CI->getBitWidth();
- assert(isPowerOf2_32(BitWidth) &&
- "Non-power-of-2-sized integers not handled!");
-
- const uint64_t *RawData = CI->getValue().getRawData();
- uint64_t Val = 0;
- for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
- Val = (TD->isBigEndian()) ? RawData[e - i - 1] : RawData[i];
- S.emitWord64(Val);
- }
-}
-
-/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
-/// special global used by LLVM. If so, emit it and return true, otherwise
-/// do nothing and return false.
-bool ELFWriter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
- if (GV->getName() == "llvm.used")
- llvm_unreachable("not implemented yet");
-
- // Ignore debug and non-emitted data. This handles llvm.compiler.used.
- if (GV->getSection() == "llvm.metadata" ||
- GV->hasAvailableExternallyLinkage())
- return true;
-
- if (!GV->hasAppendingLinkage()) return false;
-
- assert(GV->hasInitializer() && "Not a special LLVM global!");
-
- const TargetData *TD = TM.getTargetData();
- unsigned Align = TD->getPointerPrefAlignment();
- if (GV->getName() == "llvm.global_ctors") {
- ELFSection &Ctor = getCtorSection();
- Ctor.emitAlignment(Align);
- EmitXXStructorList(GV->getInitializer(), Ctor);
- return true;
- }
-
- if (GV->getName() == "llvm.global_dtors") {
- ELFSection &Dtor = getDtorSection();
- Dtor.emitAlignment(Align);
- EmitXXStructorList(GV->getInitializer(), Dtor);
- return true;
- }
-
- return false;
-}
-
-/// EmitXXStructorList - Emit the ctor or dtor list. This just emits out the
-/// function pointers, ignoring the init priority.
-void ELFWriter::EmitXXStructorList(const Constant *List, ELFSection &Xtor) {
- // Should be an array of '{ i32, void ()* }' structs. The first value is the
- // init priority, which we ignore.
- if (List->isNullValue()) return;
- const ConstantArray *InitList = cast<ConstantArray>(List);
- for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
- if (InitList->getOperand(i)->isNullValue())
- continue;
- ConstantStruct *CS = cast<ConstantStruct>(InitList->getOperand(i));
-
- if (CS->getOperand(1)->isNullValue())
- continue;
-
- // Emit the function pointer.
- EmitGlobalConstant(CS->getOperand(1), Xtor);
- }
-}
-
-bool ELFWriter::runOnMachineFunction(MachineFunction &MF) {
- // 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) {
- // 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 all pending globals
- for (PendingGblsIter I = PendingGlobals.begin(), E = PendingGlobals.end();
- I != E; ++I)
- EmitGlobal(*I);
-
- // Emit all pending externals
- for (PendingExtsIter I = PendingExternals.begin(), E = PendingExternals.end();
- I != E; ++I)
- SymbolList.push_back(ELFSym::getExtSym(*I));
-
- // 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 = ELFSym::getSectionSym();
- SectionSym->SectionIdx = ES.SectionIdx;
- SymbolList.push_back(SectionSym);
- ES.Sym = SymbolList.back();
- }
-
- // Emit string table
- EmitStringTable(M.getModuleIdentifier());
-
- // Emit the symbol table now, if non-empty.
- EmitSymbolTable();
-
- // Emit the relocation sections.
- EmitRelocations();
-
- // Emit the sections string table.
- EmitSectionTableStringTable();
-
- // Dump the sections and section table to the .o file.
- OutputSectionsAndSectionTable();
-
- return false;
-}
-
-// RelocateField - Patch relocatable field with 'Offset' in 'BO'
-// using a 'Value' of known 'Size'
-void ELFWriter::RelocateField(BinaryObject &BO, uint32_t Offset,
- int64_t Value, unsigned Size) {
- if (Size == 32)
- BO.fixWord32(Value, Offset);
- else if (Size == 64)
- BO.fixWord64(Value, Offset);
- else
- llvm_unreachable("don't know howto patch relocatable field");
-}
-
-/// EmitRelocations - Emit relocations
-void ELFWriter::EmitRelocations() {
-
- // True if the target uses the relocation entry to hold the addend,
- // otherwise the addend is written directly to the relocatable field.
- bool HasRelA = TEW->hasRelocationAddend();
-
- // 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;
- ELFSection &RelSec = getRelocSection(S);
-
- // '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;
-
- // Relocatable field offset from the section start
- unsigned RelOffset = MR.getMachineCodeOffset();
-
- // Symbol index in the symbol table
- unsigned SymIdx = 0;
-
- // Target specific relocation field type and size
- unsigned RelType = TEW->getRelocationType(MR.getRelocationType());
- unsigned RelTySize = TEW->getRelocationTySize(RelType);
- 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();
- int64_t GlobalOffset = MR.getConstantVal();
- SymIdx = GblSymLookup[G];
- if (G->hasPrivateLinkage()) {
- // If the target uses a section offset in the relocation:
- // SymIdx + Addend = section sym for global + section offset
- unsigned SectionIdx = PrivateSyms[SymIdx]->SectionIdx;
- Addend = PrivateSyms[SymIdx]->Value + GlobalOffset;
- SymIdx = SectionList[SectionIdx]->getSymbolTableIndex();
- } else {
- Addend = TEW->getDefaultAddendForRelTy(RelType, GlobalOffset);
- }
- } else if (MR.isExternalSymbol()) {
- const char *ExtSym = MR.getExternalSymbol();
- SymIdx = ExtSymLookup[ExtSym];
- Addend = TEW->getDefaultAddendForRelTy(RelType);
- } else {
- // Get the symbol index for the section symbol
- unsigned SectionIdx = MR.getConstantVal();
- SymIdx = SectionList[SectionIdx]->getSymbolTableIndex();
-
- // The symbol offset inside the section
- int64_t SymOffset = (int64_t)MR.getResultPointer();
-
- // For pc relative relocations where symbols are defined in the same
- // section they are referenced, ignore the relocation entry and patch
- // the relocatable field with the symbol offset directly.
- if (S.SectionIdx == SectionIdx && TEW->isPCRelativeRel(RelType)) {
- int64_t Value = TEW->computeRelocation(SymOffset, RelOffset, RelType);
- RelocateField(S, RelOffset, Value, RelTySize);
- continue;
- }
-
- Addend = TEW->getDefaultAddendForRelTy(RelType, SymOffset);
- }
-
- // The target without addend on the relocation symbol must be
- // patched in the relocation place itself to contain the addend
- // otherwise write zeros to make sure there is no garbage there
- RelocateField(S, RelOffset, HasRelA ? 0 : Addend, RelTySize);
-
- // Get the relocation entry and emit to the relocation section
- ELFRelocation Rel(RelOffset, 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'
-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);
- }
-}
-
-/// EmitStringTable - If the current symbol table is non-empty, emit the string
-/// table for it
-void ELFWriter::EmitStringTable(const std::string &ModuleName) {
- 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 (ELFSymIter I=SymbolList.begin(), E=SymbolList.end(); I != E; ++I) {
- ELFSym &Sym = *(*I);
-
- std::string Name;
- if (Sym.isGlobalValue()) {
- SmallString<40> NameStr;
- Mang->getNameWithPrefix(NameStr, Sym.getGlobalValue(), false);
- Name.append(NameStr.begin(), NameStr.end());
- } else if (Sym.isExternalSym())
- Name.append(Sym.getExternalSymbol());
- else if (Sym.isFileType())
- Name.append(ModuleName);
-
- if (Name.empty()) {
- Sym.NameIdx = 0;
- } else {
- Sym.NameIdx = Index;
- StrTab.emitString(Name);
-
- // Keep track of the number of bytes emitted to this section.
- Index += Name.size()+1;
- }
- }
- 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->getPrefELFAlignment();
-
- // Section Index of .strtab.
- SymTab.Link = getStringTableSection().SectionIdx;
-
- // Size of each symtab entry.
- SymTab.EntSize = TEW->getSymTabEntrySize();
-
- // 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 symbol
- if (Sym.isGlobalValue())
- GblSymLookup[Sym.getGlobalValue()] = i;
- else if (Sym.isExternalSym())
- ExtSymLookup[Sym.getExternalSymbol()] = 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();
-}
-
-/// EmitSectionTableStringTable - This method adds and emits a section for the
-/// ELF Section Table string table: the string table that holds all of the
-/// section names.
-void ELFWriter::EmitSectionTableStringTable() {
- // First step: add the section for the string table to the list of sections:
- ELFSection &SHStrTab = getSectionHeaderStringTableSection();
-
- // Now that we know which section number is the .shstrtab section, update the
- // e_shstrndx entry in the ELF header.
- 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;
-
- 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.
- S.NameIdx = Index;
- SHStrTab.emitString(S.getName());
-
- // Keep track of the number of bytes emitted to this section.
- Index += S.getName().size()+1;
- }
-
- // Set the size of .shstrtab now that we know what it is.
- assert(Index == SHStrTab.size());
- SHStrTab.Size = Index;
-}
-
-/// 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 = ElfHdr.size(); // File header first.
-
- // 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 (!ES.Size)
- ES.Size = ES.size();
-
- // Align FileOff to whatever the alignment restrictions of the section are.
- if (ES.Align)
- FileOff = (FileOff+ES.Align-1) & ~(ES.Align-1);
-
- ES.Offset = FileOff;
- FileOff += ES.Size;
- }
-
- // Align Section Header.
- 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
- // entry in the ELF header.
- 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.
- 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 *)&ElfHdr.getData()[0], ElfHdr.size());
- FileOff = ElfHdr.size();
-
- // Section Header Table blob
- BinaryObject SHdrTable(isLittleEndian, is64Bit);
-
- // Emit all of sections to the file and build the section header table.
- for (ELFSectionIter I=SectionList.begin(), E=SectionList.end(); I != E; ++I) {
- ELFSection &S = *(*I);
- DEBUG(dbgs() << "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.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);
- }
-
- // Align output for the section table.
- for (size_t NewFileOff = (FileOff+TableAlign-1) & ~(TableAlign-1);
- FileOff != NewFileOff; ++FileOff)
- O << (char)0xAB;
-
- // Emit the section table itself.
- O.write((char *)&SHdrTable.getData()[0], SHdrTable.size());
-}
+++ /dev/null
-//===-- ELFWriter.h - Target-independent ELF writer support -----*- C++ -*-===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines the ELFWriter class.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef ELFWRITER_H
-#define ELFWRITER_H
-
-#include "llvm/ADT/SetVector.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include <map>
-
-namespace llvm {
- class BinaryObject;
- class Constant;
- class ConstantInt;
- class ConstantStruct;
- class ELFCodeEmitter;
- class ELFRelocation;
- class ELFSection;
- struct ELFSym;
- class GlobalVariable;
- class JITDebugRegisterer;
- class Mangler;
- class MachineCodeEmitter;
- class MachineConstantPoolEntry;
- class ObjectCodeEmitter;
- class MCAsmInfo;
- class TargetELFWriterInfo;
- class TargetLoweringObjectFile;
- class raw_ostream;
- class SectionKind;
- class MCContext;
- class TargetMachine;
-
- typedef std::vector<ELFSym*>::iterator ELFSymIter;
- typedef std::vector<ELFSection*>::iterator ELFSectionIter;
- typedef SetVector<const GlobalValue*>::const_iterator PendingGblsIter;
- typedef SetVector<const char *>::const_iterator PendingExtsIter;
- typedef std::pair<const Constant *, int64_t> CstExprResTy;
-
- /// ELFWriter - This class implements the common target-independent code for
- /// writing ELF files. Targets should derive a class from this to
- /// parameterize the output format.
- ///
- class ELFWriter : public MachineFunctionPass {
- friend class ELFCodeEmitter;
- friend class JITDebugRegisterer;
- public:
- static char ID;
-
- /// Return the ELFCodeEmitter as an instance of ObjectCodeEmitter
- ObjectCodeEmitter *getObjectCodeEmitter() {
- return reinterpret_cast<ObjectCodeEmitter*>(ElfCE);
- }
-
- ELFWriter(raw_ostream &O, TargetMachine &TM);
- ~ELFWriter();
-
- protected:
- /// Output stream to send the resultant object file to.
- raw_ostream &O;
-
- /// Target machine description.
- TargetMachine &TM;
-
- /// Context object for machine code objects.
- MCContext &OutContext;
-
- /// Target Elf Writer description.
- const TargetELFWriterInfo *TEW;
-
- /// Mang - The object used to perform name mangling for this module.
- Mangler *Mang;
-
- /// MCE - The MachineCodeEmitter object that we are exposing to emit machine
- /// code for functions to the .o file.
- ELFCodeEmitter *ElfCE;
-
- /// TLOF - Target Lowering Object File, provide section names for globals
- /// and other object file specific stuff
- const TargetLoweringObjectFile &TLOF;
-
- /// MAI - Target Asm Info, provide information about section names for
- /// globals and other target specific stuff.
- const MCAsmInfo *MAI;
-
- //===------------------------------------------------------------------===//
- // Properties inferred automatically from the target machine.
- //===------------------------------------------------------------------===//
-
- /// is64Bit/isLittleEndian - This information is inferred from the target
- /// machine directly, indicating whether to emit a 32- or 64-bit ELF file.
- bool is64Bit, isLittleEndian;
-
- /// doInitialization - Emit the file header and all of the global variables
- /// for the module to the ELF file.
- bool doInitialization(Module &M);
- bool runOnMachineFunction(MachineFunction &MF);
-
- /// doFinalization - Now that the module has been completely processed, emit
- /// the ELF file to 'O'.
- bool doFinalization(Module &M);
-
- private:
- /// Blob containing the Elf header
- BinaryObject ElfHdr;
-
- /// SectionList - This is the list of sections that we have emitted to the
- /// file. Once the file has been completely built, the section header table
- /// is constructed from this info.
- std::vector<ELFSection*> SectionList;
- unsigned NumSections; // Always = SectionList.size()
-
- /// SectionLookup - This is a mapping from section name to section number in
- /// the SectionList. Used to quickly gather the Section Index from MAI names
- std::map<std::string, ELFSection*> SectionLookup;
-
- /// PendingGlobals - Globals not processed as symbols yet.
- SetVector<const GlobalValue*> PendingGlobals;
-
- /// GblSymLookup - This is a mapping from global value to a symbol index
- /// in the symbol table or private symbols list. This is useful since reloc
- /// symbol references must be quickly mapped to their indices on the lists.
- std::map<const GlobalValue*, uint32_t> GblSymLookup;
-
- /// PendingExternals - Externals not processed as symbols yet.
- SetVector<const char *> PendingExternals;
-
- /// ExtSymLookup - This is a mapping from externals to a symbol index
- /// in the symbol table list. This is useful since reloc symbol references
- /// must be quickly mapped to their symbol table indices.
- std::map<const char *, uint32_t> ExtSymLookup;
-
- /// SymbolList - This is the list of symbols emitted to the symbol table.
- /// When the SymbolList is finally built, local symbols must be placed in
- /// the beginning while non-locals at the end.
- std::vector<ELFSym*> SymbolList;
-
- /// PrivateSyms - Record private symbols, every symbol here must never be
- /// present in the SymbolList.
- std::vector<ELFSym*> PrivateSyms;
-
- /// getSection - Return the section with the specified name, creating a new
- /// section if one does not already exist.
- ELFSection &getSection(const std::string &Name, unsigned Type,
- unsigned Flags = 0, unsigned Align = 0) {
- ELFSection *&SN = SectionLookup[Name];
- if (SN) return *SN;
-
- SectionList.push_back(new ELFSection(Name, isLittleEndian, is64Bit));
- SN = SectionList.back();
- SN->SectionIdx = NumSections++;
- SN->Type = Type;
- SN->Flags = Flags;
- SN->Link = ELF::SHN_UNDEF;
- SN->Align = Align;
- return *SN;
- }
-
- ELFSection &getNonExecStackSection() {
- return getSection(".note.GNU-stack", ELF::SHT_PROGBITS, 0, 1);
- }
-
- ELFSection &getSymbolTableSection() {
- return getSection(".symtab", ELF::SHT_SYMTAB, 0);
- }
-
- ELFSection &getStringTableSection() {
- return getSection(".strtab", ELF::SHT_STRTAB, 0, 1);
- }
-
- ELFSection &getSectionHeaderStringTableSection() {
- return getSection(".shstrtab", ELF::SHT_STRTAB, 0, 1);
- }
-
- ELFSection &getNullSection() {
- return getSection("", ELF::SHT_NULL, 0);
- }
-
- ELFSection &getDataSection();
- ELFSection &getBSSSection();
- ELFSection &getCtorSection();
- ELFSection &getDtorSection();
- ELFSection &getJumpTableSection();
- ELFSection &getConstantPoolSection(MachineConstantPoolEntry &CPE);
- ELFSection &getTextSection(const Function *F);
- ELFSection &getRelocSection(ELFSection &S);
-
- // Helpers for obtaining ELF specific info.
- unsigned getGlobalELFBinding(const GlobalValue *GV);
- unsigned getGlobalELFType(const GlobalValue *GV);
- unsigned getGlobalELFVisibility(const GlobalValue *GV);
-
- // AddPendingGlobalSymbol - Add a global to be processed and to
- // the global symbol lookup, use a zero index because the table
- // index will be determined later.
- void AddPendingGlobalSymbol(const GlobalValue *GV,
- bool AddToLookup = false);
-
- // AddPendingExternalSymbol - Add the external to be processed
- // and to the external symbol lookup, use a zero index because
- // the symbol table index will be determined later.
- void AddPendingExternalSymbol(const char *External);
-
- // AddToSymbolList - Update the symbol lookup and If the symbol is
- // private add it to PrivateSyms list, otherwise to SymbolList.
- void AddToSymbolList(ELFSym *GblSym);
-
- // As we complete the ELF file, we need to update fields in the ELF header
- // (e.g. the location of the section table). These members keep track of
- // the offset in ELFHeader of these various pieces to update and other
- // locations in the file.
- unsigned ELFHdr_e_shoff_Offset; // e_shoff in ELF header.
- unsigned ELFHdr_e_shstrndx_Offset; // e_shstrndx in ELF header.
- unsigned ELFHdr_e_shnum_Offset; // e_shnum in ELF header.
-
- private:
- void EmitGlobal(const GlobalValue *GV);
- void EmitGlobalConstant(const Constant *C, ELFSection &GblS);
- void EmitGlobalConstantStruct(const ConstantStruct *CVS,
- ELFSection &GblS);
- void EmitGlobalConstantLargeInt(const ConstantInt *CI, ELFSection &S);
- void EmitGlobalDataRelocation(const GlobalValue *GV, unsigned Size,
- ELFSection &GblS, int64_t Offset = 0);
- bool EmitSpecialLLVMGlobal(const GlobalVariable *GV);
- void EmitXXStructorList(const Constant *List, ELFSection &Xtor);
- void EmitRelocations();
- void EmitRelocation(BinaryObject &RelSec, ELFRelocation &Rel, bool HasRelA);
- void EmitSectionHeader(BinaryObject &SHdrTab, const ELFSection &SHdr);
- void EmitSectionTableStringTable();
- void EmitSymbol(BinaryObject &SymbolTable, ELFSym &Sym);
- void EmitSymbolTable();
- void EmitStringTable(const std::string &ModuleName);
- void OutputSectionsAndSectionTable();
- void RelocateField(BinaryObject &BO, uint32_t Offset, int64_t Value,
- unsigned Size);
- unsigned SortSymbols();
- CstExprResTy ResolveConstantExpr(const Constant *CV);
- };
-}
-
-#endif