Split MCEELFStreamer and ELFObjectWriter into .h and .cpp files, so that other components can use them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126942 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 391 insertions, 0 deletions

diff --git a/lib/MC/ELFObjectWriter.h b/lib/MC/ELFObjectWriter.h
new file mode 100644
index 0000000000..9457623556
--- /dev/null
+++ b/lib/MC/ELFObjectWriter.h
@@ -0,0 +1,391 @@
+//===- lib/MC/ELFObjectWriter.h - ELF File Writer -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements ELF object file writer information.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_ELFOBJECTWRITER_H
+#define LLVM_MC_ELFOBJECTWRITER_H
+
+#include "MCELF.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCELFObjectWriter.h"
+#include "llvm/MC/MCELFSymbolFlags.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSymbol.h"
+
+#include <vector>
+
+namespace llvm {
+
+class MCSection;
+class MCDataFragment;
+class MCSectionELF;
+
+class ELFObjectWriter : public MCObjectWriter {
+  protected:
+
+    static bool isFixupKindPCRel(const MCAssembler &Asm, unsigned Kind);
+    static bool RelocNeedsGOT(MCSymbolRefExpr::VariantKind Variant);
+    static uint64_t SymbolValue(MCSymbolData &Data, const MCAsmLayout &Layout);
+    static bool isInSymtab(const MCAssembler &Asm, const MCSymbolData &Data,
+                           bool Used, bool Renamed);
+    static bool isLocal(const MCSymbolData &Data, bool isSignature,
+                        bool isUsedInReloc);
+    static bool IsELFMetaDataSection(const MCSectionData &SD);
+    static uint64_t DataSectionSize(const MCSectionData &SD);
+    static uint64_t GetSectionFileSize(const MCAsmLayout &Layout,
+                                       const MCSectionData &SD);
+    static uint64_t GetSectionAddressSize(const MCAsmLayout &Layout,
+                                          const MCSectionData &SD);
+    static void WriteDataSectionData(ELFObjectWriter *W,
+                                     const MCSectionData &SD);
+
+    /*static bool isFixupKindX86RIPRel(unsigned Kind) {
+      return Kind == X86::reloc_riprel_4byte ||
+        Kind == X86::reloc_riprel_4byte_movq_load;
+    }*/
+
+    /// ELFSymbolData - Helper struct for containing some precomputed
+    /// information on symbols.
+    struct ELFSymbolData {
+      MCSymbolData *SymbolData;
+      uint64_t StringIndex;
+      uint32_t SectionIndex;
+
+      // Support lexicographic sorting.
+      bool operator<(const ELFSymbolData &RHS) const {
+        if (MCELF::GetType(*SymbolData) == ELF::STT_FILE)
+          return true;
+        if (MCELF::GetType(*RHS.SymbolData) == ELF::STT_FILE)
+          return false;
+        return SymbolData->getSymbol().getName() <
+               RHS.SymbolData->getSymbol().getName();
+      }
+    };
+
+    /// @name Relocation Data
+    /// @{
+
+    struct ELFRelocationEntry {
+      // Make these big enough for both 32-bit and 64-bit
+      uint64_t r_offset;
+      int Index;
+      unsigned Type;
+      const MCSymbol *Symbol;
+      uint64_t r_addend;
+
+      ELFRelocationEntry()
+        : r_offset(0), Index(0), Type(0), Symbol(0), r_addend(0) {}
+
+      ELFRelocationEntry(uint64_t RelocOffset, int Idx,
+                         unsigned RelType, const MCSymbol *Sym,
+                         uint64_t Addend)
+        : r_offset(RelocOffset), Index(Idx), Type(RelType),
+          Symbol(Sym), r_addend(Addend) {}
+
+      // Support lexicographic sorting.
+      bool operator<(const ELFRelocationEntry &RE) const {
+        return RE.r_offset < r_offset;
+      }
+    };
+
+    /// The target specific ELF writer instance.
+    llvm::OwningPtr<MCELFObjectTargetWriter> TargetObjectWriter;
+
+    SmallPtrSet<const MCSymbol *, 16> UsedInReloc;
+    SmallPtrSet<const MCSymbol *, 16> WeakrefUsedInReloc;
+    DenseMap<const MCSymbol *, const MCSymbol *> Renames;
+
+    llvm::DenseMap<const MCSectionData*,
+                   std::vector<ELFRelocationEntry> > Relocations;
+    DenseMap<const MCSection*, uint64_t> SectionStringTableIndex;
+
+    /// @}
+    /// @name Symbol Table Data
+    /// @{
+
+    SmallString<256> StringTable;
+    std::vector<ELFSymbolData> LocalSymbolData;
+    std::vector<ELFSymbolData> ExternalSymbolData;
+    std::vector<ELFSymbolData> UndefinedSymbolData;
+
+    /// @}
+
+    bool NeedsGOT;
+
+    bool NeedsSymtabShndx;
+
+    // This holds the symbol table index of the last local symbol.
+    unsigned LastLocalSymbolIndex;
+    // This holds the .strtab section index.
+    unsigned StringTableIndex;
+    // This holds the .symtab section index.
+    unsigned SymbolTableIndex;
+
+    unsigned ShstrtabIndex;
+
+
+    const MCSymbol *SymbolToReloc(const MCAssembler &Asm,
+                                  const MCValue &Target,
+                                  const MCFragment &F) const;
+
+    // For arch-specific emission of explicit reloc symbol
+    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
+                                           const MCValue &Target,
+                                           const MCFragment &F,
+                                           bool IsBSS) const {
+      return NULL;
+    }
+
+    bool is64Bit() const { return TargetObjectWriter->is64Bit(); }
+    bool hasRelocationAddend() const {
+      return TargetObjectWriter->hasRelocationAddend();
+    }
+
+  public:
+    ELFObjectWriter(MCELFObjectTargetWriter *MOTW,
+                    raw_ostream &_OS, bool IsLittleEndian)
+      : MCObjectWriter(_OS, IsLittleEndian),
+        TargetObjectWriter(MOTW),
+        NeedsGOT(false), NeedsSymtabShndx(false){
+    }
+
+    virtual ~ELFObjectWriter();
+
+    void WriteWord(uint64_t W) {
+      if (is64Bit())
+        Write64(W);
+      else
+        Write32(W);
+    }
+
+    void StringLE16(char *buf, uint16_t Value) {
+      buf[0] = char(Value >> 0);
+      buf[1] = char(Value >> 8);
+    }
+
+    void StringLE32(char *buf, uint32_t Value) {
+      StringLE16(buf, uint16_t(Value >> 0));
+      StringLE16(buf + 2, uint16_t(Value >> 16));
+    }
+
+    void StringLE64(char *buf, uint64_t Value) {
+      StringLE32(buf, uint32_t(Value >> 0));
+      StringLE32(buf + 4, uint32_t(Value >> 32));
+    }
+
+    void StringBE16(char *buf ,uint16_t Value) {
+      buf[0] = char(Value >> 8);
+      buf[1] = char(Value >> 0);
+    }
+
+    void StringBE32(char *buf, uint32_t Value) {
+      StringBE16(buf, uint16_t(Value >> 16));
+      StringBE16(buf + 2, uint16_t(Value >> 0));
+    }
+
+    void StringBE64(char *buf, uint64_t Value) {
+      StringBE32(buf, uint32_t(Value >> 32));
+      StringBE32(buf + 4, uint32_t(Value >> 0));
+    }
+
+    void String8(MCDataFragment &F, uint8_t Value) {
+      char buf[1];
+      buf[0] = Value;
+      F.getContents() += StringRef(buf, 1);
+    }
+
+    void String16(MCDataFragment &F, uint16_t Value) {
+      char buf[2];
+      if (isLittleEndian())
+        StringLE16(buf, Value);
+      else
+        StringBE16(buf, Value);
+      F.getContents() += StringRef(buf, 2);
+    }
+
+    void String32(MCDataFragment &F, uint32_t Value) {
+      char buf[4];
+      if (isLittleEndian())
+        StringLE32(buf, Value);
+      else
+        StringBE32(buf, Value);
+      F.getContents() += StringRef(buf, 4);
+    }
+
+    void String64(MCDataFragment &F, uint64_t Value) {
+      char buf[8];
+      if (isLittleEndian())
+        StringLE64(buf, Value);
+      else
+        StringBE64(buf, Value);
+      F.getContents() += StringRef(buf, 8);
+    }
+
+    virtual void WriteHeader(uint64_t SectionDataSize, unsigned NumberOfSections);
+
+    /// Default e_flags = 0
+    virtual void WriteEFlags() { Write32(0); }
+
+    virtual void 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);
+
+    virtual void WriteSymbol(MCDataFragment *SymtabF,  MCDataFragment *ShndxF,
+                     ELFSymbolData &MSD,
+                     const MCAsmLayout &Layout);
+
+    typedef DenseMap<const MCSectionELF*, uint32_t> SectionIndexMapTy;
+    virtual void WriteSymbolTable(MCDataFragment *SymtabF, MCDataFragment *ShndxF,
+                          const MCAssembler &Asm,
+                          const MCAsmLayout &Layout,
+                          const SectionIndexMapTy &SectionIndexMap);
+
+    virtual void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
+                                  const MCFragment *Fragment, const MCFixup &Fixup,
+                                  MCValue Target, uint64_t &FixedValue);
+
+    virtual uint64_t getSymbolIndexInSymbolTable(const MCAssembler &Asm,
+                                         const MCSymbol *S);
+
+    // Map from a group section to the signature symbol
+    typedef DenseMap<const MCSectionELF*, const MCSymbol*> GroupMapTy;
+    // Map from a signature symbol to the group section
+    typedef DenseMap<const MCSymbol*, const MCSectionELF*> RevGroupMapTy;
+
+    /// ComputeSymbolTable - Compute the symbol table data
+    ///
+    /// \param StringTable [out] - The string table data.
+    /// \param StringIndexMap [out] - Map from symbol names to offsets in the
+    /// string table.
+    virtual void ComputeSymbolTable(MCAssembler &Asm,
+                            const SectionIndexMapTy &SectionIndexMap,
+                            RevGroupMapTy RevGroupMap);
+
+    virtual void ComputeIndexMap(MCAssembler &Asm,
+                         SectionIndexMapTy &SectionIndexMap);
+
+    virtual void WriteRelocation(MCAssembler &Asm, MCAsmLayout &Layout,
+                         const MCSectionData &SD);
+
+    virtual void WriteRelocations(MCAssembler &Asm, MCAsmLayout &Layout) {
+      for (MCAssembler::const_iterator it = Asm.begin(),
+             ie = Asm.end(); it != ie; ++it) {
+        WriteRelocation(Asm, Layout, *it);
+      }
+    }
+
+    virtual void CreateMetadataSections(MCAssembler &Asm, MCAsmLayout &Layout,
+                                const SectionIndexMapTy &SectionIndexMap);
+
+    // Create the sections that show up in the symbol table. Currently
+    // those are the .note.GNU-stack section and the group sections.
+    virtual void CreateIndexedSections(MCAssembler &Asm, MCAsmLayout &Layout,
+                                       GroupMapTy &GroupMap,
+                                       RevGroupMapTy &RevGroupMap);
+
+    virtual void ExecutePostLayoutBinding(MCAssembler &Asm,
+                                          const MCAsmLayout &Layout);
+
+    virtual void 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);
+
+    virtual void WriteRelocationsFragment(const MCAssembler &Asm,
+                                          MCDataFragment *F,
+                                          const MCSectionData *SD);
+
+    virtual bool
+    IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
+                                           const MCSymbolData &DataA,
+                                           const MCFragment &FB,
+                                           bool InSet,
+                                           bool IsPCRel) const;
+
+    virtual void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout);
+    virtual void WriteSection(MCAssembler &Asm,
+                      const SectionIndexMapTy &SectionIndexMap,
+                      uint32_t GroupSymbolIndex,
+                      uint64_t Offset, uint64_t Size, uint64_t Alignment,
+                      const MCSectionELF &Section);
+
+  protected:
+    virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
+                                  bool IsPCRel, bool IsRelocWithSymbol,
+                                  int64_t Addend) = 0;
+  };
+
+  //===- X86ELFObjectWriter -------------------------------------------===//
+
+  class X86ELFObjectWriter : public ELFObjectWriter {
+  public:
+    X86ELFObjectWriter(MCELFObjectTargetWriter *MOTW,
+                       raw_ostream &_OS,
+                       bool IsLittleEndian);
+
+    virtual ~X86ELFObjectWriter();
+  protected:
+    virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
+                                  bool IsPCRel, bool IsRelocWithSymbol,
+                                  int64_t Addend);
+  };
+
+
+  //===- ARMELFObjectWriter -------------------------------------------===//
+
+  class ARMELFObjectWriter : public ELFObjectWriter {
+  public:
+    // FIXME: MCAssembler can't yet return the Subtarget,
+    enum { DefaultEABIVersion = 0x05000000U };
+
+    ARMELFObjectWriter(MCELFObjectTargetWriter *MOTW,
+                       raw_ostream &_OS,
+                       bool IsLittleEndian);
+
+    virtual ~ARMELFObjectWriter();
+
+    virtual void WriteEFlags();
+  protected:
+    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
+                                           const MCValue &Target,
+                                           const MCFragment &F,
+                                           bool IsBSS) const;
+
+    virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
+                                  bool IsPCRel, bool IsRelocWithSymbol,
+                                  int64_t Addend);
+  };
+
+  //===- MBlazeELFObjectWriter -------------------------------------------===//
+
+  class MBlazeELFObjectWriter : public ELFObjectWriter {
+  public:
+    MBlazeELFObjectWriter(MCELFObjectTargetWriter *MOTW,
+                          raw_ostream &_OS,
+                          bool IsLittleEndian);
+
+    virtual ~MBlazeELFObjectWriter();
+  protected:
+    virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
+                                  bool IsPCRel, bool IsRelocWithSymbol,
+                                  int64_t Addend);
+  };
+}
+
+#endif