mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-27 15:29:51 +00:00
failures with relocations. The code committed is a first cut at compatibility for emitted relocations in ELF .o. Why do this? because existing ARM tools like emitting relocs symbols as explicit relocations, not as section-offset relocs. Result is that with these changes, 1) relocs are now substantially identical what to gcc outputs. 2) larger apps (including many spec2k tests) compile, cross-link, and pass Added reminder fixme to tests for future conversion to .s form. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124996 91177308-0d34-0410-b5e6-96231b3b80d8
1867 lines
61 KiB
C++
1867 lines
61 KiB
C++
//===- lib/MC/ELFObjectWriter.cpp - ELF File Writer -------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements ELF object file writer information.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/ADT/OwningPtr.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/StringMap.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/MC/MCAssembler.h"
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#include "llvm/MC/MCAsmLayout.h"
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#include "llvm/MC/MCContext.h"
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#include "llvm/MC/MCELFSymbolFlags.h"
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#include "llvm/MC/MCExpr.h"
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#include "llvm/MC/MCELFObjectWriter.h"
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#include "llvm/MC/MCObjectWriter.h"
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#include "llvm/MC/MCSectionELF.h"
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#include "llvm/MC/MCSymbol.h"
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#include "llvm/MC/MCValue.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/ELF.h"
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#include "llvm/Target/TargetAsmBackend.h"
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#include "llvm/ADT/StringSwitch.h"
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#include "../Target/X86/X86FixupKinds.h"
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#include "../Target/ARM/ARMFixupKinds.h"
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#include <vector>
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using namespace llvm;
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static unsigned GetType(const MCSymbolData &SD) {
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uint32_t Type = (SD.getFlags() & (0xf << ELF_STT_Shift)) >> ELF_STT_Shift;
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assert(Type == ELF::STT_NOTYPE || Type == ELF::STT_OBJECT ||
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Type == ELF::STT_FUNC || Type == ELF::STT_SECTION ||
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Type == ELF::STT_FILE || Type == ELF::STT_COMMON ||
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Type == ELF::STT_TLS);
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return Type;
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}
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static unsigned GetBinding(const MCSymbolData &SD) {
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uint32_t Binding = (SD.getFlags() & (0xf << ELF_STB_Shift)) >> ELF_STB_Shift;
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assert(Binding == ELF::STB_LOCAL || Binding == ELF::STB_GLOBAL ||
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Binding == ELF::STB_WEAK);
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return Binding;
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}
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static void SetBinding(MCSymbolData &SD, unsigned Binding) {
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assert(Binding == ELF::STB_LOCAL || Binding == ELF::STB_GLOBAL ||
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Binding == ELF::STB_WEAK);
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uint32_t OtherFlags = SD.getFlags() & ~(0xf << ELF_STB_Shift);
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SD.setFlags(OtherFlags | (Binding << ELF_STB_Shift));
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}
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static unsigned GetVisibility(MCSymbolData &SD) {
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unsigned Visibility =
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(SD.getFlags() & (0xf << ELF_STV_Shift)) >> ELF_STV_Shift;
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assert(Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_INTERNAL ||
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Visibility == ELF::STV_HIDDEN || Visibility == ELF::STV_PROTECTED);
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return Visibility;
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}
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static bool RelocNeedsGOT(MCSymbolRefExpr::VariantKind Variant) {
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switch (Variant) {
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default:
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return false;
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case MCSymbolRefExpr::VK_GOT:
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case MCSymbolRefExpr::VK_PLT:
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case MCSymbolRefExpr::VK_GOTPCREL:
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case MCSymbolRefExpr::VK_TPOFF:
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case MCSymbolRefExpr::VK_TLSGD:
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case MCSymbolRefExpr::VK_GOTTPOFF:
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case MCSymbolRefExpr::VK_INDNTPOFF:
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case MCSymbolRefExpr::VK_NTPOFF:
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case MCSymbolRefExpr::VK_GOTNTPOFF:
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case MCSymbolRefExpr::VK_TLSLDM:
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case MCSymbolRefExpr::VK_DTPOFF:
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case MCSymbolRefExpr::VK_TLSLD:
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return true;
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}
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}
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static bool isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind) {
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const MCFixupKindInfo &FKI =
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Asm.getBackend().getFixupKindInfo((MCFixupKind) Kind);
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return FKI.Flags & MCFixupKindInfo::FKF_IsPCRel;
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}
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namespace {
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class ELFObjectWriter : public MCObjectWriter {
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protected:
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/*static bool isFixupKindX86RIPRel(unsigned Kind) {
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return Kind == X86::reloc_riprel_4byte ||
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Kind == X86::reloc_riprel_4byte_movq_load;
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}*/
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/// ELFSymbolData - Helper struct for containing some precomputed information
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/// on symbols.
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struct ELFSymbolData {
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MCSymbolData *SymbolData;
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uint64_t StringIndex;
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uint32_t SectionIndex;
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// Support lexicographic sorting.
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bool operator<(const ELFSymbolData &RHS) const {
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if (GetType(*SymbolData) == ELF::STT_FILE)
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return true;
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if (GetType(*RHS.SymbolData) == ELF::STT_FILE)
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return false;
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return SymbolData->getSymbol().getName() <
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RHS.SymbolData->getSymbol().getName();
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}
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};
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/// @name Relocation Data
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/// @{
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struct ELFRelocationEntry {
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// Make these big enough for both 32-bit and 64-bit
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uint64_t r_offset;
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int Index;
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unsigned Type;
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const MCSymbol *Symbol;
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uint64_t r_addend;
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ELFRelocationEntry()
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: r_offset(0), Index(0), Type(0), Symbol(0), r_addend(0) {}
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ELFRelocationEntry(uint64_t RelocOffset, int Idx,
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unsigned RelType, const MCSymbol *Sym,
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uint64_t Addend)
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: r_offset(RelocOffset), Index(Idx), Type(RelType),
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Symbol(Sym), r_addend(Addend) {}
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// Support lexicographic sorting.
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bool operator<(const ELFRelocationEntry &RE) const {
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return RE.r_offset < r_offset;
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}
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};
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/// The target specific ELF writer instance.
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llvm::OwningPtr<MCELFObjectTargetWriter> TargetObjectWriter;
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SmallPtrSet<const MCSymbol *, 16> UsedInReloc;
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SmallPtrSet<const MCSymbol *, 16> WeakrefUsedInReloc;
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DenseMap<const MCSymbol *, const MCSymbol *> Renames;
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llvm::DenseMap<const MCSectionData*,
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std::vector<ELFRelocationEntry> > Relocations;
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DenseMap<const MCSection*, uint64_t> SectionStringTableIndex;
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/// @}
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/// @name Symbol Table Data
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/// @{
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SmallString<256> StringTable;
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std::vector<ELFSymbolData> LocalSymbolData;
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std::vector<ELFSymbolData> ExternalSymbolData;
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std::vector<ELFSymbolData> UndefinedSymbolData;
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/// @}
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bool NeedsGOT;
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bool NeedsSymtabShndx;
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// This holds the symbol table index of the last local symbol.
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unsigned LastLocalSymbolIndex;
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// This holds the .strtab section index.
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unsigned StringTableIndex;
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// This holds the .symtab section index.
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unsigned SymbolTableIndex;
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unsigned ShstrtabIndex;
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const MCSymbol *SymbolToReloc(const MCAssembler &Asm,
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const MCValue &Target,
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const MCFragment &F) const;
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// For arch-specific emission of explicit reloc symbol
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virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
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const MCValue &Target,
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const MCFragment &F,
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bool IsBSS) const {
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return NULL;
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}
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bool is64Bit() const { return TargetObjectWriter->is64Bit(); }
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bool hasRelocationAddend() const {
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return TargetObjectWriter->hasRelocationAddend();
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}
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public:
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ELFObjectWriter(MCELFObjectTargetWriter *MOTW,
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raw_ostream &_OS, bool IsLittleEndian)
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: MCObjectWriter(_OS, IsLittleEndian),
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TargetObjectWriter(MOTW),
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NeedsGOT(false), NeedsSymtabShndx(false){
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}
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virtual ~ELFObjectWriter();
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void WriteWord(uint64_t W) {
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if (is64Bit())
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Write64(W);
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else
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Write32(W);
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}
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void StringLE16(char *buf, uint16_t Value) {
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buf[0] = char(Value >> 0);
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buf[1] = char(Value >> 8);
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}
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void StringLE32(char *buf, uint32_t Value) {
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StringLE16(buf, uint16_t(Value >> 0));
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StringLE16(buf + 2, uint16_t(Value >> 16));
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}
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void StringLE64(char *buf, uint64_t Value) {
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StringLE32(buf, uint32_t(Value >> 0));
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StringLE32(buf + 4, uint32_t(Value >> 32));
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}
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void StringBE16(char *buf ,uint16_t Value) {
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buf[0] = char(Value >> 8);
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buf[1] = char(Value >> 0);
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}
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void StringBE32(char *buf, uint32_t Value) {
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StringBE16(buf, uint16_t(Value >> 16));
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StringBE16(buf + 2, uint16_t(Value >> 0));
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}
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void StringBE64(char *buf, uint64_t Value) {
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StringBE32(buf, uint32_t(Value >> 32));
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StringBE32(buf + 4, uint32_t(Value >> 0));
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}
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void String8(MCDataFragment &F, uint8_t Value) {
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char buf[1];
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buf[0] = Value;
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F.getContents() += StringRef(buf, 1);
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}
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void String16(MCDataFragment &F, uint16_t Value) {
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char buf[2];
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if (isLittleEndian())
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StringLE16(buf, Value);
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else
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StringBE16(buf, Value);
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F.getContents() += StringRef(buf, 2);
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}
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void String32(MCDataFragment &F, uint32_t Value) {
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char buf[4];
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if (isLittleEndian())
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StringLE32(buf, Value);
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else
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StringBE32(buf, Value);
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F.getContents() += StringRef(buf, 4);
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}
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void String64(MCDataFragment &F, uint64_t Value) {
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char buf[8];
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if (isLittleEndian())
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StringLE64(buf, Value);
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else
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StringBE64(buf, Value);
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F.getContents() += StringRef(buf, 8);
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}
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virtual void WriteHeader(uint64_t SectionDataSize, unsigned NumberOfSections);
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/// Default e_flags = 0
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virtual void WriteEFlags() { Write32(0); }
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virtual void WriteSymbolEntry(MCDataFragment *SymtabF, MCDataFragment *ShndxF,
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uint64_t name, uint8_t info,
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uint64_t value, uint64_t size,
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uint8_t other, uint32_t shndx,
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bool Reserved);
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virtual void WriteSymbol(MCDataFragment *SymtabF, MCDataFragment *ShndxF,
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ELFSymbolData &MSD,
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const MCAsmLayout &Layout);
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typedef DenseMap<const MCSectionELF*, uint32_t> SectionIndexMapTy;
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virtual void WriteSymbolTable(MCDataFragment *SymtabF, MCDataFragment *ShndxF,
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const MCAssembler &Asm,
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const MCAsmLayout &Layout,
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const SectionIndexMapTy &SectionIndexMap);
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virtual void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
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const MCFragment *Fragment, const MCFixup &Fixup,
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MCValue Target, uint64_t &FixedValue);
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virtual uint64_t getSymbolIndexInSymbolTable(const MCAssembler &Asm,
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const MCSymbol *S);
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// Map from a group section to the signature symbol
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typedef DenseMap<const MCSectionELF*, const MCSymbol*> GroupMapTy;
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// Map from a signature symbol to the group section
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typedef DenseMap<const MCSymbol*, const MCSectionELF*> RevGroupMapTy;
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/// ComputeSymbolTable - Compute the symbol table data
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///
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/// \param StringTable [out] - The string table data.
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/// \param StringIndexMap [out] - Map from symbol names to offsets in the
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/// string table.
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virtual void ComputeSymbolTable(MCAssembler &Asm,
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const SectionIndexMapTy &SectionIndexMap,
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RevGroupMapTy RevGroupMap);
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virtual void ComputeIndexMap(MCAssembler &Asm,
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SectionIndexMapTy &SectionIndexMap);
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virtual void WriteRelocation(MCAssembler &Asm, MCAsmLayout &Layout,
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const MCSectionData &SD);
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virtual void WriteRelocations(MCAssembler &Asm, MCAsmLayout &Layout) {
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for (MCAssembler::const_iterator it = Asm.begin(),
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ie = Asm.end(); it != ie; ++it) {
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WriteRelocation(Asm, Layout, *it);
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}
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}
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virtual void CreateMetadataSections(MCAssembler &Asm, MCAsmLayout &Layout,
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const SectionIndexMapTy &SectionIndexMap);
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// Create the sections that show up in the symbol table. Currently
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// those are the .note.GNU-stack section and the group sections.
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virtual void CreateIndexedSections(MCAssembler &Asm, MCAsmLayout &Layout,
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GroupMapTy &GroupMap,
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RevGroupMapTy &RevGroupMap);
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virtual void ExecutePostLayoutBinding(MCAssembler &Asm,
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const MCAsmLayout &Layout);
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virtual void WriteSecHdrEntry(uint32_t Name, uint32_t Type, uint64_t Flags,
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uint64_t Address, uint64_t Offset,
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uint64_t Size, uint32_t Link, uint32_t Info,
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uint64_t Alignment, uint64_t EntrySize);
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virtual void WriteRelocationsFragment(const MCAssembler &Asm,
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MCDataFragment *F,
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const MCSectionData *SD);
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virtual bool
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IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
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const MCSymbolData &DataA,
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const MCFragment &FB,
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bool InSet,
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bool IsPCRel) const;
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virtual void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout);
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virtual void WriteSection(MCAssembler &Asm,
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const SectionIndexMapTy &SectionIndexMap,
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uint32_t GroupSymbolIndex,
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uint64_t Offset, uint64_t Size, uint64_t Alignment,
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const MCSectionELF &Section);
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protected:
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virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
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bool IsPCRel, bool IsRelocWithSymbol,
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int64_t Addend) = 0;
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};
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//===- X86ELFObjectWriter -------------------------------------------===//
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class X86ELFObjectWriter : public ELFObjectWriter {
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public:
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X86ELFObjectWriter(MCELFObjectTargetWriter *MOTW,
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raw_ostream &_OS,
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bool IsLittleEndian);
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virtual ~X86ELFObjectWriter();
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protected:
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virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
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bool IsPCRel, bool IsRelocWithSymbol,
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int64_t Addend);
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};
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//===- ARMELFObjectWriter -------------------------------------------===//
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class ARMELFObjectWriter : public ELFObjectWriter {
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public:
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// FIXME: MCAssembler can't yet return the Subtarget,
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enum { DefaultEABIVersion = 0x05000000U };
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ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW,
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raw_ostream &_OS,
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bool IsLittleEndian);
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virtual ~ARMELFObjectWriter();
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virtual void WriteEFlags();
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protected:
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virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
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const MCValue &Target,
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const MCFragment &F,
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bool IsBSS) const;
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virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
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bool IsPCRel, bool IsRelocWithSymbol,
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int64_t Addend);
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};
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//===- MBlazeELFObjectWriter -------------------------------------------===//
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class MBlazeELFObjectWriter : public ELFObjectWriter {
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public:
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MBlazeELFObjectWriter(MCELFObjectTargetWriter *MOTW,
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raw_ostream &_OS,
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bool IsLittleEndian);
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virtual ~MBlazeELFObjectWriter();
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protected:
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virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
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bool IsPCRel, bool IsRelocWithSymbol,
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int64_t Addend);
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};
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}
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ELFObjectWriter::~ELFObjectWriter()
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{}
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// Emit the ELF header.
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void ELFObjectWriter::WriteHeader(uint64_t SectionDataSize,
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unsigned NumberOfSections) {
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// ELF Header
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// ----------
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//
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// Note
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// ----
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// emitWord method behaves differently for ELF32 and ELF64, writing
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// 4 bytes in the former and 8 in the latter.
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Write8(0x7f); // e_ident[EI_MAG0]
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Write8('E'); // e_ident[EI_MAG1]
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Write8('L'); // e_ident[EI_MAG2]
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Write8('F'); // e_ident[EI_MAG3]
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Write8(is64Bit() ? ELF::ELFCLASS64 : ELF::ELFCLASS32); // e_ident[EI_CLASS]
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// e_ident[EI_DATA]
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Write8(isLittleEndian() ? ELF::ELFDATA2LSB : ELF::ELFDATA2MSB);
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Write8(ELF::EV_CURRENT); // e_ident[EI_VERSION]
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// e_ident[EI_OSABI]
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switch (TargetObjectWriter->getOSType()) {
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case Triple::FreeBSD: Write8(ELF::ELFOSABI_FREEBSD); break;
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case Triple::Linux: Write8(ELF::ELFOSABI_LINUX); break;
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default: Write8(ELF::ELFOSABI_NONE); break;
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}
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Write8(0); // e_ident[EI_ABIVERSION]
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WriteZeros(ELF::EI_NIDENT - ELF::EI_PAD);
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Write16(ELF::ET_REL); // e_type
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Write16(TargetObjectWriter->getEMachine()); // e_machine = target
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Write32(ELF::EV_CURRENT); // e_version
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WriteWord(0); // e_entry, no entry point in .o file
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WriteWord(0); // e_phoff, no program header for .o
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WriteWord(SectionDataSize + (is64Bit() ? sizeof(ELF::Elf64_Ehdr) :
|
|
sizeof(ELF::Elf32_Ehdr))); // e_shoff = sec hdr table off in bytes
|
|
|
|
// e_flags = whatever the target wants
|
|
WriteEFlags();
|
|
|
|
// e_ehsize = ELF header size
|
|
Write16(is64Bit() ? sizeof(ELF::Elf64_Ehdr) : sizeof(ELF::Elf32_Ehdr));
|
|
|
|
Write16(0); // e_phentsize = prog header entry size
|
|
Write16(0); // e_phnum = # prog header entries = 0
|
|
|
|
// e_shentsize = Section header entry size
|
|
Write16(is64Bit() ? sizeof(ELF::Elf64_Shdr) : sizeof(ELF::Elf32_Shdr));
|
|
|
|
// e_shnum = # of section header ents
|
|
if (NumberOfSections >= ELF::SHN_LORESERVE)
|
|
Write16(0);
|
|
else
|
|
Write16(NumberOfSections);
|
|
|
|
// e_shstrndx = Section # of '.shstrtab'
|
|
if (NumberOfSections >= ELF::SHN_LORESERVE)
|
|
Write16(ELF::SHN_XINDEX);
|
|
else
|
|
Write16(ShstrtabIndex);
|
|
}
|
|
|
|
void ELFObjectWriter::WriteSymbolEntry(MCDataFragment *SymtabF,
|
|
MCDataFragment *ShndxF,
|
|
uint64_t name,
|
|
uint8_t info, uint64_t value,
|
|
uint64_t size, uint8_t other,
|
|
uint32_t shndx,
|
|
bool Reserved) {
|
|
if (ShndxF) {
|
|
if (shndx >= ELF::SHN_LORESERVE && !Reserved)
|
|
String32(*ShndxF, shndx);
|
|
else
|
|
String32(*ShndxF, 0);
|
|
}
|
|
|
|
uint16_t Index = (shndx >= ELF::SHN_LORESERVE && !Reserved) ?
|
|
uint16_t(ELF::SHN_XINDEX) : shndx;
|
|
|
|
if (is64Bit()) {
|
|
String32(*SymtabF, name); // st_name
|
|
String8(*SymtabF, info); // st_info
|
|
String8(*SymtabF, other); // st_other
|
|
String16(*SymtabF, Index); // st_shndx
|
|
String64(*SymtabF, value); // st_value
|
|
String64(*SymtabF, size); // st_size
|
|
} else {
|
|
String32(*SymtabF, name); // st_name
|
|
String32(*SymtabF, value); // st_value
|
|
String32(*SymtabF, size); // st_size
|
|
String8(*SymtabF, info); // st_info
|
|
String8(*SymtabF, other); // st_other
|
|
String16(*SymtabF, Index); // st_shndx
|
|
}
|
|
}
|
|
|
|
static uint64_t SymbolValue(MCSymbolData &Data, const MCAsmLayout &Layout) {
|
|
if (Data.isCommon() && Data.isExternal())
|
|
return Data.getCommonAlignment();
|
|
|
|
const MCSymbol &Symbol = Data.getSymbol();
|
|
|
|
if (Symbol.isAbsolute() && Symbol.isVariable()) {
|
|
if (const MCExpr *Value = Symbol.getVariableValue()) {
|
|
int64_t IntValue;
|
|
if (Value->EvaluateAsAbsolute(IntValue, Layout))
|
|
return (uint64_t)IntValue;
|
|
}
|
|
}
|
|
|
|
if (!Symbol.isInSection())
|
|
return 0;
|
|
|
|
if (Data.getFragment())
|
|
return Layout.getSymbolOffset(&Data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void ELFObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm,
|
|
const MCAsmLayout &Layout) {
|
|
// The presence of symbol versions causes undefined symbols and
|
|
// versions declared with @@@ to be renamed.
|
|
|
|
for (MCAssembler::symbol_iterator it = Asm.symbol_begin(),
|
|
ie = Asm.symbol_end(); it != ie; ++it) {
|
|
const MCSymbol &Alias = it->getSymbol();
|
|
const MCSymbol &Symbol = Alias.AliasedSymbol();
|
|
MCSymbolData &SD = Asm.getSymbolData(Symbol);
|
|
|
|
// Not an alias.
|
|
if (&Symbol == &Alias)
|
|
continue;
|
|
|
|
StringRef AliasName = Alias.getName();
|
|
size_t Pos = AliasName.find('@');
|
|
if (Pos == StringRef::npos)
|
|
continue;
|
|
|
|
// Aliases defined with .symvar copy the binding from the symbol they alias.
|
|
// This is the first place we are able to copy this information.
|
|
it->setExternal(SD.isExternal());
|
|
SetBinding(*it, GetBinding(SD));
|
|
|
|
StringRef Rest = AliasName.substr(Pos);
|
|
if (!Symbol.isUndefined() && !Rest.startswith("@@@"))
|
|
continue;
|
|
|
|
// FIXME: produce a better error message.
|
|
if (Symbol.isUndefined() && Rest.startswith("@@") &&
|
|
!Rest.startswith("@@@"))
|
|
report_fatal_error("A @@ version cannot be undefined");
|
|
|
|
Renames.insert(std::make_pair(&Symbol, &Alias));
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::WriteSymbol(MCDataFragment *SymtabF,
|
|
MCDataFragment *ShndxF,
|
|
ELFSymbolData &MSD,
|
|
const MCAsmLayout &Layout) {
|
|
MCSymbolData &OrigData = *MSD.SymbolData;
|
|
MCSymbolData &Data =
|
|
Layout.getAssembler().getSymbolData(OrigData.getSymbol().AliasedSymbol());
|
|
|
|
bool IsReserved = Data.isCommon() || Data.getSymbol().isAbsolute() ||
|
|
Data.getSymbol().isVariable();
|
|
|
|
uint8_t Binding = GetBinding(OrigData);
|
|
uint8_t Visibility = GetVisibility(OrigData);
|
|
uint8_t Type = GetType(Data);
|
|
|
|
uint8_t Info = (Binding << ELF_STB_Shift) | (Type << ELF_STT_Shift);
|
|
uint8_t Other = Visibility;
|
|
|
|
uint64_t Value = SymbolValue(Data, Layout);
|
|
uint64_t Size = 0;
|
|
|
|
assert(!(Data.isCommon() && !Data.isExternal()));
|
|
|
|
const MCExpr *ESize = Data.getSize();
|
|
if (ESize) {
|
|
int64_t Res;
|
|
if (!ESize->EvaluateAsAbsolute(Res, Layout))
|
|
report_fatal_error("Size expression must be absolute.");
|
|
Size = Res;
|
|
}
|
|
|
|
// Write out the symbol table entry
|
|
WriteSymbolEntry(SymtabF, ShndxF, MSD.StringIndex, Info, Value,
|
|
Size, Other, MSD.SectionIndex, IsReserved);
|
|
}
|
|
|
|
void ELFObjectWriter::WriteSymbolTable(MCDataFragment *SymtabF,
|
|
MCDataFragment *ShndxF,
|
|
const MCAssembler &Asm,
|
|
const MCAsmLayout &Layout,
|
|
const SectionIndexMapTy &SectionIndexMap) {
|
|
// The string table must be emitted first because we need the index
|
|
// into the string table for all the symbol names.
|
|
assert(StringTable.size() && "Missing string table");
|
|
|
|
// FIXME: Make sure the start of the symbol table is aligned.
|
|
|
|
// The first entry is the undefined symbol entry.
|
|
WriteSymbolEntry(SymtabF, ShndxF, 0, 0, 0, 0, 0, 0, false);
|
|
|
|
// Write the symbol table entries.
|
|
LastLocalSymbolIndex = LocalSymbolData.size() + 1;
|
|
for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i) {
|
|
ELFSymbolData &MSD = LocalSymbolData[i];
|
|
WriteSymbol(SymtabF, ShndxF, MSD, Layout);
|
|
}
|
|
|
|
// Write out a symbol table entry for each regular section.
|
|
for (MCAssembler::const_iterator i = Asm.begin(), e = Asm.end(); i != e;
|
|
++i) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(i->getSection());
|
|
if (Section.getType() == ELF::SHT_RELA ||
|
|
Section.getType() == ELF::SHT_REL ||
|
|
Section.getType() == ELF::SHT_STRTAB ||
|
|
Section.getType() == ELF::SHT_SYMTAB)
|
|
continue;
|
|
WriteSymbolEntry(SymtabF, ShndxF, 0, ELF::STT_SECTION, 0, 0,
|
|
ELF::STV_DEFAULT, SectionIndexMap.lookup(&Section), false);
|
|
LastLocalSymbolIndex++;
|
|
}
|
|
|
|
for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i) {
|
|
ELFSymbolData &MSD = ExternalSymbolData[i];
|
|
MCSymbolData &Data = *MSD.SymbolData;
|
|
assert(((Data.getFlags() & ELF_STB_Global) ||
|
|
(Data.getFlags() & ELF_STB_Weak)) &&
|
|
"External symbol requires STB_GLOBAL or STB_WEAK flag");
|
|
WriteSymbol(SymtabF, ShndxF, MSD, Layout);
|
|
if (GetBinding(Data) == ELF::STB_LOCAL)
|
|
LastLocalSymbolIndex++;
|
|
}
|
|
|
|
for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i) {
|
|
ELFSymbolData &MSD = UndefinedSymbolData[i];
|
|
MCSymbolData &Data = *MSD.SymbolData;
|
|
WriteSymbol(SymtabF, ShndxF, MSD, Layout);
|
|
if (GetBinding(Data) == ELF::STB_LOCAL)
|
|
LastLocalSymbolIndex++;
|
|
}
|
|
}
|
|
|
|
const MCSymbol *ELFObjectWriter::SymbolToReloc(const MCAssembler &Asm,
|
|
const MCValue &Target,
|
|
const MCFragment &F) const {
|
|
const MCSymbol &Symbol = Target.getSymA()->getSymbol();
|
|
const MCSymbol &ASymbol = Symbol.AliasedSymbol();
|
|
const MCSymbol *Renamed = Renames.lookup(&Symbol);
|
|
const MCSymbolData &SD = Asm.getSymbolData(Symbol);
|
|
|
|
if (ASymbol.isUndefined()) {
|
|
if (Renamed)
|
|
return Renamed;
|
|
return &ASymbol;
|
|
}
|
|
|
|
if (SD.isExternal()) {
|
|
if (Renamed)
|
|
return Renamed;
|
|
return &Symbol;
|
|
}
|
|
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(ASymbol.getSection());
|
|
const SectionKind secKind = Section.getKind();
|
|
|
|
if (secKind.isBSS())
|
|
return ExplicitRelSym(Asm, Target, F, true);
|
|
|
|
if (secKind.isThreadLocal()) {
|
|
if (Renamed)
|
|
return Renamed;
|
|
return &Symbol;
|
|
}
|
|
|
|
MCSymbolRefExpr::VariantKind Kind = Target.getSymA()->getKind();
|
|
const MCSectionELF &Sec2 =
|
|
static_cast<const MCSectionELF&>(F.getParent()->getSection());
|
|
|
|
if (&Sec2 != &Section &&
|
|
(Kind == MCSymbolRefExpr::VK_PLT ||
|
|
Kind == MCSymbolRefExpr::VK_GOTPCREL ||
|
|
Kind == MCSymbolRefExpr::VK_GOTOFF)) {
|
|
if (Renamed)
|
|
return Renamed;
|
|
return &Symbol;
|
|
}
|
|
|
|
if (Section.getFlags() & ELF::SHF_MERGE) {
|
|
if (Target.getConstant() == 0)
|
|
return NULL;
|
|
if (Renamed)
|
|
return Renamed;
|
|
return &Symbol;
|
|
}
|
|
|
|
return ExplicitRelSym(Asm, Target, F, false);
|
|
}
|
|
|
|
|
|
void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm,
|
|
const MCAsmLayout &Layout,
|
|
const MCFragment *Fragment,
|
|
const MCFixup &Fixup,
|
|
MCValue Target,
|
|
uint64_t &FixedValue) {
|
|
int64_t Addend = 0;
|
|
int Index = 0;
|
|
int64_t Value = Target.getConstant();
|
|
const MCSymbol *RelocSymbol = NULL;
|
|
|
|
bool IsPCRel = isFixupKindPCRel(Asm, Fixup.getKind());
|
|
if (!Target.isAbsolute()) {
|
|
const MCSymbol &Symbol = Target.getSymA()->getSymbol();
|
|
const MCSymbol &ASymbol = Symbol.AliasedSymbol();
|
|
RelocSymbol = SymbolToReloc(Asm, Target, *Fragment);
|
|
|
|
if (const MCSymbolRefExpr *RefB = Target.getSymB()) {
|
|
const MCSymbol &SymbolB = RefB->getSymbol();
|
|
MCSymbolData &SDB = Asm.getSymbolData(SymbolB);
|
|
IsPCRel = true;
|
|
|
|
// Offset of the symbol in the section
|
|
int64_t a = Layout.getSymbolOffset(&SDB);
|
|
|
|
// Ofeset of the relocation in the section
|
|
int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
|
|
Value += b - a;
|
|
}
|
|
|
|
if (!RelocSymbol) {
|
|
MCSymbolData &SD = Asm.getSymbolData(ASymbol);
|
|
MCFragment *F = SD.getFragment();
|
|
|
|
Index = F->getParent()->getOrdinal() + 1;
|
|
|
|
// Offset of the symbol in the section
|
|
Value += Layout.getSymbolOffset(&SD);
|
|
} else {
|
|
if (Asm.getSymbolData(Symbol).getFlags() & ELF_Other_Weakref)
|
|
WeakrefUsedInReloc.insert(RelocSymbol);
|
|
else
|
|
UsedInReloc.insert(RelocSymbol);
|
|
Index = -1;
|
|
}
|
|
Addend = Value;
|
|
// Compensate for the addend on i386.
|
|
if (is64Bit())
|
|
Value = 0;
|
|
}
|
|
|
|
FixedValue = Value;
|
|
unsigned Type = GetRelocType(Target, Fixup, IsPCRel,
|
|
(RelocSymbol != 0), Addend);
|
|
|
|
uint64_t RelocOffset = Layout.getFragmentOffset(Fragment) +
|
|
Fixup.getOffset();
|
|
|
|
if (!hasRelocationAddend())
|
|
Addend = 0;
|
|
ELFRelocationEntry ERE(RelocOffset, Index, Type, RelocSymbol, Addend);
|
|
Relocations[Fragment->getParent()].push_back(ERE);
|
|
}
|
|
|
|
|
|
uint64_t
|
|
ELFObjectWriter::getSymbolIndexInSymbolTable(const MCAssembler &Asm,
|
|
const MCSymbol *S) {
|
|
MCSymbolData &SD = Asm.getSymbolData(*S);
|
|
return SD.getIndex();
|
|
}
|
|
|
|
static bool isInSymtab(const MCAssembler &Asm, const MCSymbolData &Data,
|
|
bool Used, bool Renamed) {
|
|
if (Data.getFlags() & ELF_Other_Weakref)
|
|
return false;
|
|
|
|
if (Used)
|
|
return true;
|
|
|
|
if (Renamed)
|
|
return false;
|
|
|
|
const MCSymbol &Symbol = Data.getSymbol();
|
|
|
|
if (Symbol.getName() == "_GLOBAL_OFFSET_TABLE_")
|
|
return true;
|
|
|
|
const MCSymbol &A = Symbol.AliasedSymbol();
|
|
if (!A.isVariable() && A.isUndefined() && !Data.isCommon())
|
|
return false;
|
|
|
|
if (!Asm.isSymbolLinkerVisible(Symbol) && !Symbol.isUndefined())
|
|
return false;
|
|
|
|
if (Symbol.isTemporary())
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static bool isLocal(const MCSymbolData &Data, bool isSignature,
|
|
bool isUsedInReloc) {
|
|
if (Data.isExternal())
|
|
return false;
|
|
|
|
const MCSymbol &Symbol = Data.getSymbol();
|
|
const MCSymbol &RefSymbol = Symbol.AliasedSymbol();
|
|
|
|
if (RefSymbol.isUndefined() && !RefSymbol.isVariable()) {
|
|
if (isSignature && !isUsedInReloc)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void ELFObjectWriter::ComputeIndexMap(MCAssembler &Asm,
|
|
SectionIndexMapTy &SectionIndexMap) {
|
|
unsigned Index = 1;
|
|
for (MCAssembler::iterator it = Asm.begin(),
|
|
ie = Asm.end(); it != ie; ++it) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF &>(it->getSection());
|
|
if (Section.getType() != ELF::SHT_GROUP)
|
|
continue;
|
|
SectionIndexMap[&Section] = Index++;
|
|
}
|
|
|
|
for (MCAssembler::iterator it = Asm.begin(),
|
|
ie = Asm.end(); it != ie; ++it) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF &>(it->getSection());
|
|
if (Section.getType() == ELF::SHT_GROUP)
|
|
continue;
|
|
SectionIndexMap[&Section] = Index++;
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::ComputeSymbolTable(MCAssembler &Asm,
|
|
const SectionIndexMapTy &SectionIndexMap,
|
|
RevGroupMapTy RevGroupMap) {
|
|
// FIXME: Is this the correct place to do this?
|
|
if (NeedsGOT) {
|
|
llvm::StringRef Name = "_GLOBAL_OFFSET_TABLE_";
|
|
MCSymbol *Sym = Asm.getContext().GetOrCreateSymbol(Name);
|
|
MCSymbolData &Data = Asm.getOrCreateSymbolData(*Sym);
|
|
Data.setExternal(true);
|
|
SetBinding(Data, ELF::STB_GLOBAL);
|
|
}
|
|
|
|
// Build section lookup table.
|
|
int NumRegularSections = Asm.size();
|
|
|
|
// Index 0 is always the empty string.
|
|
StringMap<uint64_t> StringIndexMap;
|
|
StringTable += '\x00';
|
|
|
|
// Add the data for the symbols.
|
|
for (MCAssembler::symbol_iterator it = Asm.symbol_begin(),
|
|
ie = Asm.symbol_end(); it != ie; ++it) {
|
|
const MCSymbol &Symbol = it->getSymbol();
|
|
|
|
bool Used = UsedInReloc.count(&Symbol);
|
|
bool WeakrefUsed = WeakrefUsedInReloc.count(&Symbol);
|
|
bool isSignature = RevGroupMap.count(&Symbol);
|
|
|
|
if (!isInSymtab(Asm, *it,
|
|
Used || WeakrefUsed || isSignature,
|
|
Renames.count(&Symbol)))
|
|
continue;
|
|
|
|
ELFSymbolData MSD;
|
|
MSD.SymbolData = it;
|
|
const MCSymbol &RefSymbol = Symbol.AliasedSymbol();
|
|
|
|
// Undefined symbols are global, but this is the first place we
|
|
// are able to set it.
|
|
bool Local = isLocal(*it, isSignature, Used);
|
|
if (!Local && GetBinding(*it) == ELF::STB_LOCAL) {
|
|
MCSymbolData &SD = Asm.getSymbolData(RefSymbol);
|
|
SetBinding(*it, ELF::STB_GLOBAL);
|
|
SetBinding(SD, ELF::STB_GLOBAL);
|
|
}
|
|
|
|
if (RefSymbol.isUndefined() && !Used && WeakrefUsed)
|
|
SetBinding(*it, ELF::STB_WEAK);
|
|
|
|
if (it->isCommon()) {
|
|
assert(!Local);
|
|
MSD.SectionIndex = ELF::SHN_COMMON;
|
|
} else if (Symbol.isAbsolute() || RefSymbol.isVariable()) {
|
|
MSD.SectionIndex = ELF::SHN_ABS;
|
|
} else if (RefSymbol.isUndefined()) {
|
|
if (isSignature && !Used)
|
|
MSD.SectionIndex = SectionIndexMap.lookup(RevGroupMap[&Symbol]);
|
|
else
|
|
MSD.SectionIndex = ELF::SHN_UNDEF;
|
|
} else {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(RefSymbol.getSection());
|
|
MSD.SectionIndex = SectionIndexMap.lookup(&Section);
|
|
if (MSD.SectionIndex >= ELF::SHN_LORESERVE)
|
|
NeedsSymtabShndx = true;
|
|
assert(MSD.SectionIndex && "Invalid section index!");
|
|
}
|
|
|
|
// The @@@ in symbol version is replaced with @ in undefined symbols and
|
|
// @@ in defined ones.
|
|
StringRef Name = Symbol.getName();
|
|
SmallString<32> Buf;
|
|
|
|
size_t Pos = Name.find("@@@");
|
|
if (Pos != StringRef::npos) {
|
|
Buf += Name.substr(0, Pos);
|
|
unsigned Skip = MSD.SectionIndex == ELF::SHN_UNDEF ? 2 : 1;
|
|
Buf += Name.substr(Pos + Skip);
|
|
Name = Buf;
|
|
}
|
|
|
|
uint64_t &Entry = StringIndexMap[Name];
|
|
if (!Entry) {
|
|
Entry = StringTable.size();
|
|
StringTable += Name;
|
|
StringTable += '\x00';
|
|
}
|
|
MSD.StringIndex = Entry;
|
|
if (MSD.SectionIndex == ELF::SHN_UNDEF)
|
|
UndefinedSymbolData.push_back(MSD);
|
|
else if (Local)
|
|
LocalSymbolData.push_back(MSD);
|
|
else
|
|
ExternalSymbolData.push_back(MSD);
|
|
}
|
|
|
|
// Symbols are required to be in lexicographic order.
|
|
array_pod_sort(LocalSymbolData.begin(), LocalSymbolData.end());
|
|
array_pod_sort(ExternalSymbolData.begin(), ExternalSymbolData.end());
|
|
array_pod_sort(UndefinedSymbolData.begin(), UndefinedSymbolData.end());
|
|
|
|
// Set the symbol indices. Local symbols must come before all other
|
|
// symbols with non-local bindings.
|
|
unsigned Index = 1;
|
|
for (unsigned i = 0, e = LocalSymbolData.size(); i != e; ++i)
|
|
LocalSymbolData[i].SymbolData->setIndex(Index++);
|
|
|
|
Index += NumRegularSections;
|
|
|
|
for (unsigned i = 0, e = ExternalSymbolData.size(); i != e; ++i)
|
|
ExternalSymbolData[i].SymbolData->setIndex(Index++);
|
|
for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i)
|
|
UndefinedSymbolData[i].SymbolData->setIndex(Index++);
|
|
}
|
|
|
|
void ELFObjectWriter::WriteRelocation(MCAssembler &Asm, MCAsmLayout &Layout,
|
|
const MCSectionData &SD) {
|
|
if (!Relocations[&SD].empty()) {
|
|
MCContext &Ctx = Asm.getContext();
|
|
const MCSectionELF *RelaSection;
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(SD.getSection());
|
|
|
|
const StringRef SectionName = Section.getSectionName();
|
|
std::string RelaSectionName = hasRelocationAddend() ? ".rela" : ".rel";
|
|
RelaSectionName += SectionName;
|
|
|
|
unsigned EntrySize;
|
|
if (hasRelocationAddend())
|
|
EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rela) : sizeof(ELF::Elf32_Rela);
|
|
else
|
|
EntrySize = is64Bit() ? sizeof(ELF::Elf64_Rel) : sizeof(ELF::Elf32_Rel);
|
|
|
|
RelaSection = Ctx.getELFSection(RelaSectionName, hasRelocationAddend() ?
|
|
ELF::SHT_RELA : ELF::SHT_REL, 0,
|
|
SectionKind::getReadOnly(),
|
|
EntrySize, "");
|
|
|
|
MCSectionData &RelaSD = Asm.getOrCreateSectionData(*RelaSection);
|
|
RelaSD.setAlignment(is64Bit() ? 8 : 4);
|
|
|
|
MCDataFragment *F = new MCDataFragment(&RelaSD);
|
|
|
|
WriteRelocationsFragment(Asm, F, &SD);
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::WriteSecHdrEntry(uint32_t Name, uint32_t Type,
|
|
uint64_t Flags, uint64_t Address,
|
|
uint64_t Offset, uint64_t Size,
|
|
uint32_t Link, uint32_t Info,
|
|
uint64_t Alignment,
|
|
uint64_t EntrySize) {
|
|
Write32(Name); // sh_name: index into string table
|
|
Write32(Type); // sh_type
|
|
WriteWord(Flags); // sh_flags
|
|
WriteWord(Address); // sh_addr
|
|
WriteWord(Offset); // sh_offset
|
|
WriteWord(Size); // sh_size
|
|
Write32(Link); // sh_link
|
|
Write32(Info); // sh_info
|
|
WriteWord(Alignment); // sh_addralign
|
|
WriteWord(EntrySize); // sh_entsize
|
|
}
|
|
|
|
void ELFObjectWriter::WriteRelocationsFragment(const MCAssembler &Asm,
|
|
MCDataFragment *F,
|
|
const MCSectionData *SD) {
|
|
std::vector<ELFRelocationEntry> &Relocs = Relocations[SD];
|
|
// sort by the r_offset just like gnu as does
|
|
array_pod_sort(Relocs.begin(), Relocs.end());
|
|
|
|
for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
|
|
ELFRelocationEntry entry = Relocs[e - i - 1];
|
|
|
|
if (!entry.Index)
|
|
;
|
|
else if (entry.Index < 0)
|
|
entry.Index = getSymbolIndexInSymbolTable(Asm, entry.Symbol);
|
|
else
|
|
entry.Index += LocalSymbolData.size();
|
|
if (is64Bit()) {
|
|
String64(*F, entry.r_offset);
|
|
|
|
struct ELF::Elf64_Rela ERE64;
|
|
ERE64.setSymbolAndType(entry.Index, entry.Type);
|
|
String64(*F, ERE64.r_info);
|
|
|
|
if (hasRelocationAddend())
|
|
String64(*F, entry.r_addend);
|
|
} else {
|
|
String32(*F, entry.r_offset);
|
|
|
|
struct ELF::Elf32_Rela ERE32;
|
|
ERE32.setSymbolAndType(entry.Index, entry.Type);
|
|
String32(*F, ERE32.r_info);
|
|
|
|
if (hasRelocationAddend())
|
|
String32(*F, entry.r_addend);
|
|
}
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::CreateMetadataSections(MCAssembler &Asm,
|
|
MCAsmLayout &Layout,
|
|
const SectionIndexMapTy &SectionIndexMap) {
|
|
MCContext &Ctx = Asm.getContext();
|
|
MCDataFragment *F;
|
|
|
|
unsigned EntrySize = is64Bit() ? ELF::SYMENTRY_SIZE64 : ELF::SYMENTRY_SIZE32;
|
|
|
|
// We construct .shstrtab, .symtab and .strtab in this order to match gnu as.
|
|
const MCSectionELF *ShstrtabSection =
|
|
Ctx.getELFSection(".shstrtab", ELF::SHT_STRTAB, 0,
|
|
SectionKind::getReadOnly());
|
|
MCSectionData &ShstrtabSD = Asm.getOrCreateSectionData(*ShstrtabSection);
|
|
ShstrtabSD.setAlignment(1);
|
|
ShstrtabIndex = Asm.size();
|
|
|
|
const MCSectionELF *SymtabSection =
|
|
Ctx.getELFSection(".symtab", ELF::SHT_SYMTAB, 0,
|
|
SectionKind::getReadOnly(),
|
|
EntrySize, "");
|
|
MCSectionData &SymtabSD = Asm.getOrCreateSectionData(*SymtabSection);
|
|
SymtabSD.setAlignment(is64Bit() ? 8 : 4);
|
|
SymbolTableIndex = Asm.size();
|
|
|
|
MCSectionData *SymtabShndxSD = NULL;
|
|
|
|
if (NeedsSymtabShndx) {
|
|
const MCSectionELF *SymtabShndxSection =
|
|
Ctx.getELFSection(".symtab_shndx", ELF::SHT_SYMTAB_SHNDX, 0,
|
|
SectionKind::getReadOnly(), 4, "");
|
|
SymtabShndxSD = &Asm.getOrCreateSectionData(*SymtabShndxSection);
|
|
SymtabShndxSD->setAlignment(4);
|
|
}
|
|
|
|
const MCSection *StrtabSection;
|
|
StrtabSection = Ctx.getELFSection(".strtab", ELF::SHT_STRTAB, 0,
|
|
SectionKind::getReadOnly());
|
|
MCSectionData &StrtabSD = Asm.getOrCreateSectionData(*StrtabSection);
|
|
StrtabSD.setAlignment(1);
|
|
StringTableIndex = Asm.size();
|
|
|
|
WriteRelocations(Asm, Layout);
|
|
|
|
// Symbol table
|
|
F = new MCDataFragment(&SymtabSD);
|
|
MCDataFragment *ShndxF = NULL;
|
|
if (NeedsSymtabShndx) {
|
|
ShndxF = new MCDataFragment(SymtabShndxSD);
|
|
}
|
|
WriteSymbolTable(F, ShndxF, Asm, Layout, SectionIndexMap);
|
|
|
|
F = new MCDataFragment(&StrtabSD);
|
|
F->getContents().append(StringTable.begin(), StringTable.end());
|
|
|
|
F = new MCDataFragment(&ShstrtabSD);
|
|
|
|
// Section header string table.
|
|
//
|
|
// The first entry of a string table holds a null character so skip
|
|
// section 0.
|
|
uint64_t Index = 1;
|
|
F->getContents() += '\x00';
|
|
|
|
StringMap<uint64_t> SecStringMap;
|
|
for (MCAssembler::const_iterator it = Asm.begin(),
|
|
ie = Asm.end(); it != ie; ++it) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(it->getSection());
|
|
// FIXME: We could merge suffixes like in .text and .rela.text.
|
|
|
|
StringRef Name = Section.getSectionName();
|
|
if (SecStringMap.count(Name)) {
|
|
SectionStringTableIndex[&Section] = SecStringMap[Name];
|
|
continue;
|
|
}
|
|
// Remember the index into the string table so we can write it
|
|
// into the sh_name field of the section header table.
|
|
SectionStringTableIndex[&Section] = Index;
|
|
SecStringMap[Name] = Index;
|
|
|
|
Index += Name.size() + 1;
|
|
F->getContents() += Name;
|
|
F->getContents() += '\x00';
|
|
}
|
|
}
|
|
|
|
bool
|
|
ELFObjectWriter::IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
|
|
const MCSymbolData &DataA,
|
|
const MCFragment &FB,
|
|
bool InSet,
|
|
bool IsPCRel) const {
|
|
// FIXME: This is in here just to match gnu as output. If the two ends
|
|
// are in the same section, there is nothing that the linker can do to
|
|
// break it.
|
|
if (DataA.isExternal())
|
|
return false;
|
|
|
|
const MCSection &SecA = DataA.getSymbol().AliasedSymbol().getSection();
|
|
const MCSection &SecB = FB.getParent()->getSection();
|
|
// On ELF A - B is absolute if A and B are in the same section.
|
|
return &SecA == &SecB;
|
|
}
|
|
|
|
void ELFObjectWriter::CreateIndexedSections(MCAssembler &Asm,
|
|
MCAsmLayout &Layout,
|
|
GroupMapTy &GroupMap,
|
|
RevGroupMapTy &RevGroupMap) {
|
|
// Create the .note.GNU-stack section if needed.
|
|
MCContext &Ctx = Asm.getContext();
|
|
if (Asm.getNoExecStack()) {
|
|
const MCSectionELF *GnuStackSection =
|
|
Ctx.getELFSection(".note.GNU-stack", ELF::SHT_PROGBITS, 0,
|
|
SectionKind::getReadOnly());
|
|
Asm.getOrCreateSectionData(*GnuStackSection);
|
|
}
|
|
|
|
// Build the groups
|
|
for (MCAssembler::const_iterator it = Asm.begin(), ie = Asm.end();
|
|
it != ie; ++it) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(it->getSection());
|
|
if (!(Section.getFlags() & ELF::SHF_GROUP))
|
|
continue;
|
|
|
|
const MCSymbol *SignatureSymbol = Section.getGroup();
|
|
Asm.getOrCreateSymbolData(*SignatureSymbol);
|
|
const MCSectionELF *&Group = RevGroupMap[SignatureSymbol];
|
|
if (!Group) {
|
|
Group = Ctx.CreateELFGroupSection();
|
|
MCSectionData &Data = Asm.getOrCreateSectionData(*Group);
|
|
Data.setAlignment(4);
|
|
MCDataFragment *F = new MCDataFragment(&Data);
|
|
String32(*F, ELF::GRP_COMDAT);
|
|
}
|
|
GroupMap[Group] = SignatureSymbol;
|
|
}
|
|
|
|
// Add sections to the groups
|
|
unsigned Index = 1;
|
|
unsigned NumGroups = RevGroupMap.size();
|
|
for (MCAssembler::const_iterator it = Asm.begin(), ie = Asm.end();
|
|
it != ie; ++it, ++Index) {
|
|
const MCSectionELF &Section =
|
|
static_cast<const MCSectionELF&>(it->getSection());
|
|
if (!(Section.getFlags() & ELF::SHF_GROUP))
|
|
continue;
|
|
const MCSectionELF *Group = RevGroupMap[Section.getGroup()];
|
|
MCSectionData &Data = Asm.getOrCreateSectionData(*Group);
|
|
// FIXME: we could use the previous fragment
|
|
MCDataFragment *F = new MCDataFragment(&Data);
|
|
String32(*F, NumGroups + Index);
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::WriteSection(MCAssembler &Asm,
|
|
const SectionIndexMapTy &SectionIndexMap,
|
|
uint32_t GroupSymbolIndex,
|
|
uint64_t Offset, uint64_t Size,
|
|
uint64_t Alignment,
|
|
const MCSectionELF &Section) {
|
|
uint64_t sh_link = 0;
|
|
uint64_t sh_info = 0;
|
|
|
|
switch(Section.getType()) {
|
|
case ELF::SHT_DYNAMIC:
|
|
sh_link = SectionStringTableIndex[&Section];
|
|
sh_info = 0;
|
|
break;
|
|
|
|
case ELF::SHT_REL:
|
|
case ELF::SHT_RELA: {
|
|
const MCSectionELF *SymtabSection;
|
|
const MCSectionELF *InfoSection;
|
|
SymtabSection = Asm.getContext().getELFSection(".symtab", ELF::SHT_SYMTAB,
|
|
0,
|
|
SectionKind::getReadOnly());
|
|
sh_link = SectionIndexMap.lookup(SymtabSection);
|
|
assert(sh_link && ".symtab not found");
|
|
|
|
// Remove ".rel" and ".rela" prefixes.
|
|
unsigned SecNameLen = (Section.getType() == ELF::SHT_REL) ? 4 : 5;
|
|
StringRef SectionName = Section.getSectionName().substr(SecNameLen);
|
|
|
|
InfoSection = Asm.getContext().getELFSection(SectionName,
|
|
ELF::SHT_PROGBITS, 0,
|
|
SectionKind::getReadOnly());
|
|
sh_info = SectionIndexMap.lookup(InfoSection);
|
|
break;
|
|
}
|
|
|
|
case ELF::SHT_SYMTAB:
|
|
case ELF::SHT_DYNSYM:
|
|
sh_link = StringTableIndex;
|
|
sh_info = LastLocalSymbolIndex;
|
|
break;
|
|
|
|
case ELF::SHT_SYMTAB_SHNDX:
|
|
sh_link = SymbolTableIndex;
|
|
break;
|
|
|
|
case ELF::SHT_PROGBITS:
|
|
case ELF::SHT_STRTAB:
|
|
case ELF::SHT_NOBITS:
|
|
case ELF::SHT_NOTE:
|
|
case ELF::SHT_NULL:
|
|
case ELF::SHT_ARM_ATTRIBUTES:
|
|
case ELF::SHT_INIT_ARRAY:
|
|
case ELF::SHT_FINI_ARRAY:
|
|
case ELF::SHT_PREINIT_ARRAY:
|
|
case ELF::SHT_X86_64_UNWIND:
|
|
// Nothing to do.
|
|
break;
|
|
|
|
case ELF::SHT_GROUP: {
|
|
sh_link = SymbolTableIndex;
|
|
sh_info = GroupSymbolIndex;
|
|
break;
|
|
}
|
|
|
|
default:
|
|
assert(0 && "FIXME: sh_type value not supported!");
|
|
break;
|
|
}
|
|
|
|
WriteSecHdrEntry(SectionStringTableIndex[&Section], Section.getType(),
|
|
Section.getFlags(), 0, Offset, Size, sh_link, sh_info,
|
|
Alignment, Section.getEntrySize());
|
|
}
|
|
|
|
static bool IsELFMetaDataSection(const MCSectionData &SD) {
|
|
return SD.getOrdinal() == ~UINT32_C(0) &&
|
|
!SD.getSection().isVirtualSection();
|
|
}
|
|
|
|
static uint64_t DataSectionSize(const MCSectionData &SD) {
|
|
uint64_t Ret = 0;
|
|
for (MCSectionData::const_iterator i = SD.begin(), e = SD.end(); i != e;
|
|
++i) {
|
|
const MCFragment &F = *i;
|
|
assert(F.getKind() == MCFragment::FT_Data);
|
|
Ret += cast<MCDataFragment>(F).getContents().size();
|
|
}
|
|
return Ret;
|
|
}
|
|
|
|
static uint64_t GetSectionFileSize(const MCAsmLayout &Layout,
|
|
const MCSectionData &SD) {
|
|
if (IsELFMetaDataSection(SD))
|
|
return DataSectionSize(SD);
|
|
return Layout.getSectionFileSize(&SD);
|
|
}
|
|
|
|
static uint64_t GetSectionAddressSize(const MCAsmLayout &Layout,
|
|
const MCSectionData &SD) {
|
|
if (IsELFMetaDataSection(SD))
|
|
return DataSectionSize(SD);
|
|
return Layout.getSectionAddressSize(&SD);
|
|
}
|
|
|
|
static void WriteDataSectionData(ELFObjectWriter *W, const MCSectionData &SD) {
|
|
for (MCSectionData::const_iterator i = SD.begin(), e = SD.end(); i != e;
|
|
++i) {
|
|
const MCFragment &F = *i;
|
|
assert(F.getKind() == MCFragment::FT_Data);
|
|
W->WriteBytes(cast<MCDataFragment>(F).getContents().str());
|
|
}
|
|
}
|
|
|
|
void ELFObjectWriter::WriteObject(MCAssembler &Asm,
|
|
const MCAsmLayout &Layout) {
|
|
GroupMapTy GroupMap;
|
|
RevGroupMapTy RevGroupMap;
|
|
CreateIndexedSections(Asm, const_cast<MCAsmLayout&>(Layout), GroupMap,
|
|
RevGroupMap);
|
|
|
|
SectionIndexMapTy SectionIndexMap;
|
|
|
|
ComputeIndexMap(Asm, SectionIndexMap);
|
|
|
|
// Compute symbol table information.
|
|
ComputeSymbolTable(Asm, SectionIndexMap, RevGroupMap);
|
|
|
|
CreateMetadataSections(const_cast<MCAssembler&>(Asm),
|
|
const_cast<MCAsmLayout&>(Layout),
|
|
SectionIndexMap);
|
|
|
|
// Update to include the metadata sections.
|
|
ComputeIndexMap(Asm, SectionIndexMap);
|
|
|
|
// Add 1 for the null section.
|
|
unsigned NumSections = Asm.size() + 1;
|
|
uint64_t NaturalAlignment = is64Bit() ? 8 : 4;
|
|
uint64_t HeaderSize = is64Bit() ? sizeof(ELF::Elf64_Ehdr) :
|
|
sizeof(ELF::Elf32_Ehdr);
|
|
uint64_t FileOff = HeaderSize;
|
|
|
|
std::vector<const MCSectionELF*> Sections;
|
|
Sections.resize(NumSections);
|
|
|
|
for (SectionIndexMapTy::const_iterator i=
|
|
SectionIndexMap.begin(), e = SectionIndexMap.end(); i != e; ++i) {
|
|
const std::pair<const MCSectionELF*, uint32_t> &p = *i;
|
|
Sections[p.second] = p.first;
|
|
}
|
|
|
|
for (unsigned i = 1; i < NumSections; ++i) {
|
|
const MCSectionELF &Section = *Sections[i];
|
|
const MCSectionData &SD = Asm.getOrCreateSectionData(Section);
|
|
|
|
FileOff = RoundUpToAlignment(FileOff, SD.getAlignment());
|
|
|
|
// Get the size of the section in the output file (including padding).
|
|
FileOff += GetSectionFileSize(Layout, SD);
|
|
}
|
|
|
|
FileOff = RoundUpToAlignment(FileOff, NaturalAlignment);
|
|
|
|
// Write out the ELF header ...
|
|
WriteHeader(FileOff - HeaderSize, NumSections);
|
|
|
|
FileOff = HeaderSize;
|
|
|
|
// ... then all of the sections ...
|
|
DenseMap<const MCSection*, uint64_t> SectionOffsetMap;
|
|
|
|
for (unsigned i = 1; i < NumSections; ++i) {
|
|
const MCSectionELF &Section = *Sections[i];
|
|
const MCSectionData &SD = Asm.getOrCreateSectionData(Section);
|
|
|
|
uint64_t Padding = OffsetToAlignment(FileOff, SD.getAlignment());
|
|
WriteZeros(Padding);
|
|
FileOff += Padding;
|
|
|
|
// Remember the offset into the file for this section.
|
|
SectionOffsetMap[&Section] = FileOff;
|
|
|
|
FileOff += GetSectionFileSize(Layout, SD);
|
|
|
|
if (IsELFMetaDataSection(SD))
|
|
WriteDataSectionData(this, SD);
|
|
else
|
|
Asm.WriteSectionData(&SD, Layout);
|
|
}
|
|
|
|
uint64_t Padding = OffsetToAlignment(FileOff, NaturalAlignment);
|
|
WriteZeros(Padding);
|
|
FileOff += Padding;
|
|
|
|
// ... and then the section header table.
|
|
// Should we align the section header table?
|
|
//
|
|
// Null section first.
|
|
uint64_t FirstSectionSize =
|
|
NumSections >= ELF::SHN_LORESERVE ? NumSections : 0;
|
|
uint32_t FirstSectionLink =
|
|
ShstrtabIndex >= ELF::SHN_LORESERVE ? ShstrtabIndex : 0;
|
|
WriteSecHdrEntry(0, 0, 0, 0, 0, FirstSectionSize, FirstSectionLink, 0, 0, 0);
|
|
|
|
for (unsigned i = 1; i < NumSections; ++i) {
|
|
const MCSectionELF &Section = *Sections[i];
|
|
const MCSectionData &SD = Asm.getOrCreateSectionData(Section);
|
|
uint32_t GroupSymbolIndex;
|
|
if (Section.getType() != ELF::SHT_GROUP)
|
|
GroupSymbolIndex = 0;
|
|
else
|
|
GroupSymbolIndex = getSymbolIndexInSymbolTable(Asm, GroupMap[&Section]);
|
|
|
|
uint64_t Size = GetSectionAddressSize(Layout, SD);
|
|
|
|
WriteSection(Asm, SectionIndexMap, GroupSymbolIndex,
|
|
SectionOffsetMap[&Section], Size,
|
|
SD.getAlignment(), Section);
|
|
}
|
|
}
|
|
|
|
MCObjectWriter *llvm::createELFObjectWriter(MCELFObjectTargetWriter *MOTW,
|
|
raw_ostream &OS,
|
|
bool IsLittleEndian) {
|
|
switch (MOTW->getEMachine()) {
|
|
case ELF::EM_386:
|
|
case ELF::EM_X86_64:
|
|
return new X86ELFObjectWriter(MOTW, OS, IsLittleEndian); break;
|
|
case ELF::EM_ARM:
|
|
return new ARMELFObjectWriter(MOTW, OS, IsLittleEndian); break;
|
|
case ELF::EM_MBLAZE:
|
|
return new MBlazeELFObjectWriter(MOTW, OS, IsLittleEndian); break;
|
|
default: llvm_unreachable("Unsupported architecture"); break;
|
|
}
|
|
}
|
|
|
|
|
|
/// START OF SUBCLASSES for ELFObjectWriter
|
|
//===- ARMELFObjectWriter -------------------------------------------===//
|
|
|
|
ARMELFObjectWriter::ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW,
|
|
raw_ostream &_OS,
|
|
bool IsLittleEndian)
|
|
: ELFObjectWriter(MOTW, _OS, IsLittleEndian)
|
|
{}
|
|
|
|
ARMELFObjectWriter::~ARMELFObjectWriter()
|
|
{}
|
|
|
|
// FIXME: get the real EABI Version from the Triple.
|
|
void ARMELFObjectWriter::WriteEFlags() {
|
|
Write32(ELF::EF_ARM_EABIMASK & DefaultEABIVersion);
|
|
}
|
|
|
|
// In ARM, _MergedGlobals and other most symbols get emitted directly.
|
|
// I.e. not as an offset to a section symbol.
|
|
// This code is a first-cut approximation of what ARM/gcc does.
|
|
|
|
const MCSymbol *ARMELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
|
|
const MCValue &Target,
|
|
const MCFragment &F,
|
|
bool IsBSS) const {
|
|
const MCSymbol &Symbol = Target.getSymA()->getSymbol();
|
|
bool EmitThisSym = false;
|
|
|
|
if (IsBSS) {
|
|
EmitThisSym = StringSwitch<bool>(Symbol.getName())
|
|
.Case("_MergedGlobals", true)
|
|
.Default(false);
|
|
} else {
|
|
EmitThisSym = StringSwitch<bool>(Symbol.getName())
|
|
.Case("_MergedGlobals", true)
|
|
.StartsWith(".L.str", true)
|
|
.Default(false);
|
|
}
|
|
if (EmitThisSym)
|
|
return &Symbol;
|
|
if (! Symbol.isTemporary())
|
|
return &Symbol;
|
|
return NULL;
|
|
}
|
|
|
|
unsigned ARMELFObjectWriter::GetRelocType(const MCValue &Target,
|
|
const MCFixup &Fixup,
|
|
bool IsPCRel,
|
|
bool IsRelocWithSymbol,
|
|
int64_t Addend) {
|
|
MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ?
|
|
MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
|
|
|
|
unsigned Type = 0;
|
|
if (IsPCRel) {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: assert(0 && "Unimplemented");
|
|
case FK_Data_4:
|
|
switch (Modifier) {
|
|
default: llvm_unreachable("Unsupported Modifier");
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_ARM_BASE_PREL;
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_TLSGD:
|
|
assert(0 && "unimplemented");
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_GOTTPOFF:
|
|
Type = ELF::R_ARM_TLS_IE32;
|
|
break;
|
|
}
|
|
break;
|
|
case ARM::fixup_arm_uncondbranch:
|
|
switch (Modifier) {
|
|
case MCSymbolRefExpr::VK_ARM_PLT:
|
|
Type = ELF::R_ARM_PLT32;
|
|
break;
|
|
default:
|
|
Type = ELF::R_ARM_CALL;
|
|
break;
|
|
}
|
|
break;
|
|
case ARM::fixup_arm_condbranch:
|
|
Type = ELF::R_ARM_JUMP24;
|
|
break;
|
|
case ARM::fixup_arm_movt_hi16:
|
|
case ARM::fixup_arm_movt_hi16_pcrel:
|
|
Type = ELF::R_ARM_MOVT_PREL;
|
|
break;
|
|
case ARM::fixup_arm_movw_lo16:
|
|
case ARM::fixup_arm_movw_lo16_pcrel:
|
|
Type = ELF::R_ARM_MOVW_PREL_NC;
|
|
break;
|
|
case ARM::fixup_t2_movt_hi16:
|
|
case ARM::fixup_t2_movt_hi16_pcrel:
|
|
Type = ELF::R_ARM_THM_MOVT_PREL;
|
|
break;
|
|
case ARM::fixup_t2_movw_lo16:
|
|
case ARM::fixup_t2_movw_lo16_pcrel:
|
|
Type = ELF::R_ARM_THM_MOVW_PREL_NC;
|
|
break;
|
|
}
|
|
} else {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
case FK_Data_4:
|
|
switch (Modifier) {
|
|
default: llvm_unreachable("Unsupported Modifier"); break;
|
|
case MCSymbolRefExpr::VK_ARM_GOT:
|
|
Type = ELF::R_ARM_GOT_BREL;
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_TLSGD:
|
|
Type = ELF::R_ARM_TLS_GD32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_TPOFF:
|
|
Type = ELF::R_ARM_TLS_LE32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_GOTTPOFF:
|
|
Type = ELF::R_ARM_TLS_IE32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_ARM_ABS32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_ARM_GOTOFF:
|
|
Type = ELF::R_ARM_GOTOFF32;
|
|
break;
|
|
}
|
|
break;
|
|
case ARM::fixup_arm_ldst_pcrel_12:
|
|
case ARM::fixup_arm_pcrel_10:
|
|
case ARM::fixup_arm_adr_pcrel_12:
|
|
case ARM::fixup_arm_thumb_bl:
|
|
case ARM::fixup_arm_thumb_cb:
|
|
case ARM::fixup_arm_thumb_cp:
|
|
case ARM::fixup_arm_thumb_br:
|
|
assert(0 && "Unimplemented");
|
|
break;
|
|
case ARM::fixup_arm_uncondbranch:
|
|
Type = ELF::R_ARM_CALL;
|
|
break;
|
|
case ARM::fixup_arm_condbranch:
|
|
Type = ELF::R_ARM_JUMP24;
|
|
break;
|
|
case ARM::fixup_arm_movt_hi16:
|
|
Type = ELF::R_ARM_MOVT_ABS;
|
|
break;
|
|
case ARM::fixup_arm_movw_lo16:
|
|
Type = ELF::R_ARM_MOVW_ABS_NC;
|
|
break;
|
|
case ARM::fixup_t2_movt_hi16:
|
|
Type = ELF::R_ARM_THM_MOVT_ABS;
|
|
break;
|
|
case ARM::fixup_t2_movw_lo16:
|
|
Type = ELF::R_ARM_THM_MOVW_ABS_NC;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (RelocNeedsGOT(Modifier))
|
|
NeedsGOT = true;
|
|
|
|
return Type;
|
|
}
|
|
|
|
//===- MBlazeELFObjectWriter -------------------------------------------===//
|
|
|
|
MBlazeELFObjectWriter::MBlazeELFObjectWriter(MCELFObjectTargetWriter *MOTW,
|
|
raw_ostream &_OS,
|
|
bool IsLittleEndian)
|
|
: ELFObjectWriter(MOTW, _OS, IsLittleEndian) {
|
|
}
|
|
|
|
MBlazeELFObjectWriter::~MBlazeELFObjectWriter() {
|
|
}
|
|
|
|
unsigned MBlazeELFObjectWriter::GetRelocType(const MCValue &Target,
|
|
const MCFixup &Fixup,
|
|
bool IsPCRel,
|
|
bool IsRelocWithSymbol,
|
|
int64_t Addend) {
|
|
// determine the type of the relocation
|
|
unsigned Type;
|
|
if (IsPCRel) {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default:
|
|
llvm_unreachable("Unimplemented");
|
|
case FK_PCRel_4:
|
|
Type = ELF::R_MICROBLAZE_64_PCREL;
|
|
break;
|
|
case FK_PCRel_2:
|
|
Type = ELF::R_MICROBLAZE_32_PCREL;
|
|
break;
|
|
}
|
|
} else {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
case FK_Data_4:
|
|
Type = ((IsRelocWithSymbol || Addend !=0)
|
|
? ELF::R_MICROBLAZE_32
|
|
: ELF::R_MICROBLAZE_64);
|
|
break;
|
|
case FK_Data_2:
|
|
Type = ELF::R_MICROBLAZE_32;
|
|
break;
|
|
}
|
|
}
|
|
return Type;
|
|
}
|
|
|
|
//===- X86ELFObjectWriter -------------------------------------------===//
|
|
|
|
|
|
X86ELFObjectWriter::X86ELFObjectWriter(MCELFObjectTargetWriter *MOTW,
|
|
raw_ostream &_OS,
|
|
bool IsLittleEndian)
|
|
: ELFObjectWriter(MOTW, _OS, IsLittleEndian)
|
|
{}
|
|
|
|
X86ELFObjectWriter::~X86ELFObjectWriter()
|
|
{}
|
|
|
|
unsigned X86ELFObjectWriter::GetRelocType(const MCValue &Target,
|
|
const MCFixup &Fixup,
|
|
bool IsPCRel,
|
|
bool IsRelocWithSymbol,
|
|
int64_t Addend) {
|
|
// determine the type of the relocation
|
|
|
|
MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ?
|
|
MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
|
|
unsigned Type;
|
|
if (is64Bit()) {
|
|
if (IsPCRel) {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
case FK_PCRel_8:
|
|
assert(Modifier == MCSymbolRefExpr::VK_None);
|
|
Type = ELF::R_X86_64_PC64;
|
|
break;
|
|
case X86::reloc_signed_4byte:
|
|
case X86::reloc_riprel_4byte_movq_load:
|
|
case FK_Data_4: // FIXME?
|
|
case X86::reloc_riprel_4byte:
|
|
case FK_PCRel_4:
|
|
switch (Modifier) {
|
|
default:
|
|
llvm_unreachable("Unimplemented");
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_X86_64_PC32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_PLT:
|
|
Type = ELF::R_X86_64_PLT32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOTPCREL:
|
|
Type = ELF::R_X86_64_GOTPCREL;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOTTPOFF:
|
|
Type = ELF::R_X86_64_GOTTPOFF;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TLSGD:
|
|
Type = ELF::R_X86_64_TLSGD;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TLSLD:
|
|
Type = ELF::R_X86_64_TLSLD;
|
|
break;
|
|
}
|
|
break;
|
|
case FK_PCRel_2:
|
|
assert(Modifier == MCSymbolRefExpr::VK_None);
|
|
Type = ELF::R_X86_64_PC16;
|
|
break;
|
|
}
|
|
} else {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
case FK_Data_8: Type = ELF::R_X86_64_64; break;
|
|
case X86::reloc_signed_4byte:
|
|
assert(isInt<32>(Target.getConstant()));
|
|
switch (Modifier) {
|
|
default:
|
|
llvm_unreachable("Unimplemented");
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_X86_64_32S;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOT:
|
|
Type = ELF::R_X86_64_GOT32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOTPCREL:
|
|
Type = ELF::R_X86_64_GOTPCREL;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TPOFF:
|
|
Type = ELF::R_X86_64_TPOFF32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_DTPOFF:
|
|
Type = ELF::R_X86_64_DTPOFF32;
|
|
break;
|
|
}
|
|
break;
|
|
case FK_Data_4:
|
|
Type = ELF::R_X86_64_32;
|
|
break;
|
|
case FK_Data_2: Type = ELF::R_X86_64_16; break;
|
|
case FK_PCRel_1:
|
|
case FK_Data_1: Type = ELF::R_X86_64_8; break;
|
|
}
|
|
}
|
|
} else {
|
|
if (IsPCRel) {
|
|
switch (Modifier) {
|
|
default:
|
|
llvm_unreachable("Unimplemented");
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_386_PC32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_PLT:
|
|
Type = ELF::R_386_PLT32;
|
|
break;
|
|
}
|
|
} else {
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default: llvm_unreachable("invalid fixup kind!");
|
|
|
|
case X86::reloc_global_offset_table:
|
|
Type = ELF::R_386_GOTPC;
|
|
break;
|
|
|
|
// FIXME: Should we avoid selecting reloc_signed_4byte in 32 bit mode
|
|
// instead?
|
|
case X86::reloc_signed_4byte:
|
|
case FK_PCRel_4:
|
|
case FK_Data_4:
|
|
switch (Modifier) {
|
|
default:
|
|
llvm_unreachable("Unimplemented");
|
|
case MCSymbolRefExpr::VK_None:
|
|
Type = ELF::R_386_32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOT:
|
|
Type = ELF::R_386_GOT32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOTOFF:
|
|
Type = ELF::R_386_GOTOFF;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TLSGD:
|
|
Type = ELF::R_386_TLS_GD;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TPOFF:
|
|
Type = ELF::R_386_TLS_LE_32;
|
|
break;
|
|
case MCSymbolRefExpr::VK_INDNTPOFF:
|
|
Type = ELF::R_386_TLS_IE;
|
|
break;
|
|
case MCSymbolRefExpr::VK_NTPOFF:
|
|
Type = ELF::R_386_TLS_LE;
|
|
break;
|
|
case MCSymbolRefExpr::VK_GOTNTPOFF:
|
|
Type = ELF::R_386_TLS_GOTIE;
|
|
break;
|
|
case MCSymbolRefExpr::VK_TLSLDM:
|
|
Type = ELF::R_386_TLS_LDM;
|
|
break;
|
|
case MCSymbolRefExpr::VK_DTPOFF:
|
|
Type = ELF::R_386_TLS_LDO_32;
|
|
break;
|
|
}
|
|
break;
|
|
case FK_Data_2: Type = ELF::R_386_16; break;
|
|
case FK_PCRel_1:
|
|
case FK_Data_1: Type = ELF::R_386_8; break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (RelocNeedsGOT(Modifier))
|
|
NeedsGOT = true;
|
|
|
|
return Type;
|
|
}
|