X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FELF.h;h=cb5a8c0eae1d3a42c119fbc62afd28de64e78659;hb=d6060a4ce94424e0fd7b926d7cb41799b6debe4a;hp=28b6be8910e525a57ee8ad8444cf1b3e09771739;hpb=0d3193ef3ce7377eeaa1d38ca08f8a62ebcd5f63;p=oota-llvm.git diff --git a/lib/CodeGen/ELF.h b/lib/CodeGen/ELF.h index 28b6be8910e..cb5a8c0eae1 100644 --- a/lib/CodeGen/ELF.h +++ b/lib/CodeGen/ELF.h @@ -20,14 +20,12 @@ #ifndef CODEGEN_ELF_H #define CODEGEN_ELF_H -#include "llvm/GlobalVariable.h" #include "llvm/CodeGen/BinaryObject.h" #include "llvm/CodeGen/MachineRelocation.h" -#include "llvm/Support/DataTypes.h" -#include +#include "llvm/System/DataTypes.h" namespace llvm { - class BinaryObject; + class GlobalValue; // Identification Indexes enum { @@ -54,6 +52,159 @@ namespace llvm { EV_CURRENT = 1 }; + /// 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(STB_GLOBAL); + Sym->setType(STT_NOTYPE); + Sym->setVisibility(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(STB_LOCAL); + Sym->setType(STT_SECTION); + Sym->setVisibility(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(STB_LOCAL); + Sym->setType(STT_FILE); + Sym->setVisibility(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(STT_NOTYPE); + Sym->setVisibility(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; + + enum { + STB_LOCAL = 0, // Local sym, not visible outside obj file containing def + STB_GLOBAL = 1, // Global sym, visible to all object files being combined + STB_WEAK = 2 // Weak symbol, like global but lower-precedence + }; + + enum { + STT_NOTYPE = 0, // Symbol's type is not specified + STT_OBJECT = 1, // Symbol is a data object (variable, array, etc.) + STT_FUNC = 2, // Symbol is executable code (function, etc.) + STT_SECTION = 3, // Symbol refers to a section + STT_FILE = 4 // Local, absolute symbol that refers to a file + }; + + enum { + STV_DEFAULT = 0, // Visibility is specified by binding type + STV_INTERNAL = 1, // Defined by processor supplements + STV_HIDDEN = 2, // Not visible to other components + STV_PROTECTED = 3 // Visible in other components but not preemptable + }; + + ELFSym() : SourceType(isOther), NameIdx(0), Value(0), + Size(0), Info(0), Other(STV_DEFAULT), SectionIdx(0), + SymTabIdx(0) {} + + unsigned getBind() const { return (Info >> 4) & 0xf; } + unsigned getType() const { return Info & 0xf; } + bool isLocalBind() const { return getBind() == STB_LOCAL; } + bool isFileType() const { return getType() == 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. @@ -119,86 +270,19 @@ namespace llvm { /// SectionIdx - The number of the section in the Section Table. unsigned short SectionIdx; - 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) {} - }; - - /// 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 { - // The global value this corresponds to. Global symbols can be on of the - // 3 types : if this symbol has a zero initializer, it is common or should - // be placed in bss section otherwise it's a constant. - const GlobalValue *GV; - bool IsCommon; - bool IsBss; - bool IsConstant; - - // 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; - - enum { - STB_LOCAL = 0, - STB_GLOBAL = 1, - STB_WEAK = 2 - }; - - enum { - STT_NOTYPE = 0, - STT_OBJECT = 1, - STT_FUNC = 2, - STT_SECTION = 3, - STT_FILE = 4 - }; - - enum { - STV_DEFAULT = 0, // Visibility is specified by binding type - STV_INTERNAL = 1, // Defined by processor supplements - STV_HIDDEN = 2, // Not visible to other components - STV_PROTECTED = 3 // Visible in other components but not preemptable - }; + /// Sym - The symbol to represent this section if it has one. + ELFSym *Sym; - ELFSym(const GlobalValue *gv) : GV(gv), IsCommon(false), IsBss(false), - IsConstant(false), NameIdx(0), Value(0), - Size(0), Info(0), Other(STV_DEFAULT), - SectionIdx(ELFSection::SHN_UNDEF) { - if (!GV) - return; - - switch (GV->getVisibility()) { - default: - assert(0 && "unknown visibility type"); - case GlobalValue::DefaultVisibility: - Other = STV_DEFAULT; - break; - case GlobalValue::HiddenVisibility: - Other = STV_HIDDEN; - break; - case GlobalValue::ProtectedVisibility: - Other = STV_PROTECTED; - break; - } + /// 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; } - unsigned getBind() { - return (Info >> 4) & 0xf; - } - - 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; - } + 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