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Diffstat (limited to 'contrib/llvm/lib/CodeGen/ELF.h')
| -rw-r--r-- | contrib/llvm/lib/CodeGen/ELF.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/ELF.h b/contrib/llvm/lib/CodeGen/ELF.h new file mode 100644 index 0000000..e08feeb --- /dev/null +++ b/contrib/llvm/lib/CodeGen/ELF.h @@ -0,0 +1,227 @@ +//===-- lib/CodeGen/ELF.h - ELF constants and data structures ---*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This header contains common, non-processor-specific data structures and +// constants for the ELF file format. +// +// The details of the ELF32 bits in this file are largely based on the Tool +// Interface Standard (TIS) Executable and Linking Format (ELF) Specification +// Version 1.2, May 1995. The ELF64 is based on HP/Intel definition of the +// ELF-64 object file format document, Version 1.5 Draft 2 May 27, 1998 +// +//===----------------------------------------------------------------------===// + +#ifndef CODEGEN_ELF_H +#define CODEGEN_ELF_H + +#include "llvm/CodeGen/BinaryObject.h" +#include "llvm/CodeGen/MachineRelocation.h" +#include "llvm/Support/ELF.h" +#include "llvm/Support/DataTypes.h" + +namespace llvm { + class GlobalValue; + + /// ELFSym - This struct contains information about each symbol that is + /// added to logical symbol table for the module. This is eventually + /// turned into a real symbol table in the file. + struct ELFSym { + + // ELF symbols are related to llvm ones by being one of the two llvm + // types, for the other ones (section, file, func) a null pointer is + // assumed by default. + union { + const GlobalValue *GV; // If this is a pointer to a GV + const char *Ext; // If this is a pointer to a named symbol + } Source; + + // Describes from which source type this ELF symbol comes from, + // they can be GlobalValue, ExternalSymbol or neither. + enum { + isGV, // The Source.GV field is valid. + isExtSym, // The Source.ExtSym field is valid. + isOther // Not a GlobalValue or External Symbol + }; + unsigned SourceType; + + bool isGlobalValue() const { return SourceType == isGV; } + bool isExternalSym() const { return SourceType == isExtSym; } + + // getGlobalValue - If this is a global value which originated the + // elf symbol, return a reference to it. + const GlobalValue *getGlobalValue() const { + assert(SourceType == isGV && "This is not a global value"); + return Source.GV; + } + + // getExternalSym - If this is an external symbol which originated the + // elf symbol, return a reference to it. + const char *getExternalSymbol() const { + assert(SourceType == isExtSym && "This is not an external symbol"); + return Source.Ext; + } + + // getGV - From a global value return a elf symbol to represent it + static ELFSym *getGV(const GlobalValue *GV, unsigned Bind, + unsigned Type, unsigned Visibility) { + ELFSym *Sym = new ELFSym(); + Sym->Source.GV = GV; + Sym->setBind(Bind); + Sym->setType(Type); + Sym->setVisibility(Visibility); + Sym->SourceType = isGV; + return Sym; + } + + // getExtSym - Create and return an elf symbol to represent an + // external symbol + static ELFSym *getExtSym(const char *Ext) { + ELFSym *Sym = new ELFSym(); + Sym->Source.Ext = Ext; + Sym->setBind(ELF::STB_GLOBAL); + Sym->setType(ELF::STT_NOTYPE); + Sym->setVisibility(ELF::STV_DEFAULT); + Sym->SourceType = isExtSym; + return Sym; + } + + // getSectionSym - Returns a elf symbol to represent an elf section + static ELFSym *getSectionSym() { + ELFSym *Sym = new ELFSym(); + Sym->setBind(ELF::STB_LOCAL); + Sym->setType(ELF::STT_SECTION); + Sym->setVisibility(ELF::STV_DEFAULT); + Sym->SourceType = isOther; + return Sym; + } + + // getFileSym - Returns a elf symbol to represent the module identifier + static ELFSym *getFileSym() { + ELFSym *Sym = new ELFSym(); + Sym->setBind(ELF::STB_LOCAL); + Sym->setType(ELF::STT_FILE); + Sym->setVisibility(ELF::STV_DEFAULT); + Sym->SectionIdx = 0xfff1; // ELFSection::SHN_ABS; + Sym->SourceType = isOther; + return Sym; + } + + // getUndefGV - Returns a STT_NOTYPE symbol + static ELFSym *getUndefGV(const GlobalValue *GV, unsigned Bind) { + ELFSym *Sym = new ELFSym(); + Sym->Source.GV = GV; + Sym->setBind(Bind); + Sym->setType(ELF::STT_NOTYPE); + Sym->setVisibility(ELF::STV_DEFAULT); + Sym->SectionIdx = 0; //ELFSection::SHN_UNDEF; + Sym->SourceType = isGV; + return Sym; + } + + // ELF specific fields + unsigned NameIdx; // Index in .strtab of name, once emitted. + uint64_t Value; + unsigned Size; + uint8_t Info; + uint8_t Other; + unsigned short SectionIdx; + + // Symbol index into the Symbol table + unsigned SymTabIdx; + + ELFSym() : SourceType(isOther), NameIdx(0), Value(0), + Size(0), Info(0), Other(ELF::STV_DEFAULT), SectionIdx(0), + SymTabIdx(0) {} + + unsigned getBind() const { return (Info >> 4) & 0xf; } + unsigned getType() const { return Info & 0xf; } + bool isLocalBind() const { return getBind() == ELF::STB_LOCAL; } + bool isFileType() const { return getType() == ELF::STT_FILE; } + + void setBind(unsigned X) { + assert(X == (X & 0xF) && "Bind value out of range!"); + Info = (Info & 0x0F) | (X << 4); + } + + void setType(unsigned X) { + assert(X == (X & 0xF) && "Type value out of range!"); + Info = (Info & 0xF0) | X; + } + + void setVisibility(unsigned V) { + assert(V == (V & 0x3) && "Visibility value out of range!"); + Other = V; + } + }; + + /// ELFSection - This struct contains information about each section that is + /// emitted to the file. This is eventually turned into the section header + /// table at the end of the file. + class ELFSection : public BinaryObject { + public: + // ELF specific fields + unsigned NameIdx; // sh_name - .shstrtab idx of name, once emitted. + unsigned Type; // sh_type - Section contents & semantics + unsigned Flags; // sh_flags - Section flags. + uint64_t Addr; // sh_addr - The mem addr this section is in. + unsigned Offset; // sh_offset - Offset from the file start + unsigned Size; // sh_size - The section size. + unsigned Link; // sh_link - Section header table index link. + unsigned Info; // sh_info - Auxillary information. + unsigned Align; // sh_addralign - Alignment of section. + unsigned EntSize; // sh_entsize - Size of entries in the section e + + /// SectionIdx - The number of the section in the Section Table. + unsigned short SectionIdx; + + /// Sym - The symbol to represent this section if it has one. + ELFSym *Sym; + + /// getSymIndex - Returns the symbol table index of the symbol + /// representing this section. + unsigned getSymbolTableIndex() const { + assert(Sym && "section not present in the symbol table"); + return Sym->SymTabIdx; + } + + ELFSection(const std::string &name, bool isLittleEndian, bool is64Bit) + : BinaryObject(name, isLittleEndian, is64Bit), Type(0), Flags(0), Addr(0), + Offset(0), Size(0), Link(0), Info(0), Align(0), EntSize(0), Sym(0) {} + }; + + /// ELFRelocation - This class contains all the information necessary to + /// to generate any 32-bit or 64-bit ELF relocation entry. + class ELFRelocation { + uint64_t r_offset; // offset in the section of the object this applies to + uint32_t r_symidx; // symbol table index of the symbol to use + uint32_t r_type; // machine specific relocation type + int64_t r_add; // explicit relocation addend + bool r_rela; // if true then the addend is part of the entry + // otherwise the addend is at the location specified + // by r_offset + public: + uint64_t getInfo(bool is64Bit) const { + if (is64Bit) + return ((uint64_t)r_symidx << 32) + ((uint64_t)r_type & 0xFFFFFFFFL); + else + return (r_symidx << 8) + (r_type & 0xFFL); + } + + uint64_t getOffset() const { return r_offset; } + int64_t getAddend() const { return r_add; } + + ELFRelocation(uint64_t off, uint32_t sym, uint32_t type, + bool rela = true, int64_t addend = 0) : + r_offset(off), r_symidx(sym), r_type(type), + r_add(addend), r_rela(rela) {} + }; + +} // end namespace llvm + +#endif |
