llvm-6502/include/llvm/Object/ObjectFile.h
Rafael Espindola 6c1202c459 Handle relocations that don't point to symbols.
In ELF (as in MachO), not all relocations point to symbols. Represent this
properly by using a symbol_iterator instead of a SymbolRef. Update llvm-readobj
ELF's dumper to handle relocatios without symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183284 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-05 01:33:53 +00:00

623 lines
21 KiB
C++

//===- ObjectFile.h - File format independent object file -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares a file format independent ObjectFile class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_OBJECT_OBJECTFILE_H
#define LLVM_OBJECT_OBJECTFILE_H
#include "llvm/ADT/StringRef.h"
#include "llvm/Object/Binary.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MemoryBuffer.h"
#include <cstring>
#include <vector>
namespace llvm {
namespace object {
class ObjectFile;
union DataRefImpl {
// This entire union should probably be a
// char[max(8, sizeof(uintptr_t))] and require the impl to cast.
struct {
uint32_t a, b;
} d;
uintptr_t p;
DataRefImpl() {
std::memset(this, 0, sizeof(DataRefImpl));
}
};
template<class content_type>
class content_iterator {
content_type Current;
public:
content_iterator(content_type symb)
: Current(symb) {}
const content_type* operator->() const {
return &Current;
}
const content_type &operator*() const {
return Current;
}
bool operator==(const content_iterator &other) const {
return Current == other.Current;
}
bool operator!=(const content_iterator &other) const {
return !(*this == other);
}
content_iterator& increment(error_code &err) {
content_type next;
if (error_code ec = Current.getNext(next))
err = ec;
else
Current = next;
return *this;
}
};
inline bool operator==(const DataRefImpl &a, const DataRefImpl &b) {
// Check bitwise identical. This is the only legal way to compare a union w/o
// knowing which member is in use.
return std::memcmp(&a, &b, sizeof(DataRefImpl)) == 0;
}
inline bool operator<(const DataRefImpl &a, const DataRefImpl &b) {
// Check bitwise identical. This is the only legal way to compare a union w/o
// knowing which member is in use.
return std::memcmp(&a, &b, sizeof(DataRefImpl)) < 0;
}
class SymbolRef;
typedef content_iterator<SymbolRef> symbol_iterator;
/// RelocationRef - This is a value type class that represents a single
/// relocation in the list of relocations in the object file.
class RelocationRef {
DataRefImpl RelocationPimpl;
const ObjectFile *OwningObject;
public:
RelocationRef() : OwningObject(NULL) { }
RelocationRef(DataRefImpl RelocationP, const ObjectFile *Owner);
bool operator==(const RelocationRef &Other) const;
error_code getNext(RelocationRef &Result) const;
error_code getAddress(uint64_t &Result) const;
error_code getOffset(uint64_t &Result) const;
symbol_iterator getSymbol() const;
error_code getType(uint64_t &Result) const;
/// @brief Indicates whether this relocation should hidden when listing
/// relocations, usually because it is the trailing part of a multipart
/// relocation that will be printed as part of the leading relocation.
error_code getHidden(bool &Result) const;
/// @brief Get a string that represents the type of this relocation.
///
/// This is for display purposes only.
error_code getTypeName(SmallVectorImpl<char> &Result) const;
/// @brief Get a string that represents the calculation of the value of this
/// relocation.
///
/// This is for display purposes only.
error_code getValueString(SmallVectorImpl<char> &Result) const;
DataRefImpl getRawDataRefImpl() const;
const ObjectFile *getObjectFile() const;
};
typedef content_iterator<RelocationRef> relocation_iterator;
/// SectionRef - This is a value type class that represents a single section in
/// the list of sections in the object file.
class SectionRef;
typedef content_iterator<SectionRef> section_iterator;
class SectionRef {
friend class SymbolRef;
DataRefImpl SectionPimpl;
const ObjectFile *OwningObject;
public:
SectionRef() : OwningObject(NULL) { }
SectionRef(DataRefImpl SectionP, const ObjectFile *Owner);
bool operator==(const SectionRef &Other) const;
bool operator<(const SectionRef &Other) const;
error_code getNext(SectionRef &Result) const;
error_code getName(StringRef &Result) const;
error_code getAddress(uint64_t &Result) const;
error_code getSize(uint64_t &Result) const;
error_code getContents(StringRef &Result) const;
/// @brief Get the alignment of this section as the actual value (not log 2).
error_code getAlignment(uint64_t &Result) const;
// FIXME: Move to the normalization layer when it's created.
error_code isText(bool &Result) const;
error_code isData(bool &Result) const;
error_code isBSS(bool &Result) const;
error_code isRequiredForExecution(bool &Result) const;
error_code isVirtual(bool &Result) const;
error_code isZeroInit(bool &Result) const;
error_code isReadOnlyData(bool &Result) const;
error_code containsSymbol(SymbolRef S, bool &Result) const;
relocation_iterator begin_relocations() const;
relocation_iterator end_relocations() const;
section_iterator getRelocatedSection() const;
DataRefImpl getRawDataRefImpl() const;
};
/// SymbolRef - This is a value type class that represents a single symbol in
/// the list of symbols in the object file.
class SymbolRef {
friend class SectionRef;
DataRefImpl SymbolPimpl;
const ObjectFile *OwningObject;
public:
SymbolRef() : OwningObject(NULL) { }
enum Type {
ST_Unknown, // Type not specified
ST_Data,
ST_Debug,
ST_File,
ST_Function,
ST_Other
};
enum Flags {
SF_None = 0,
SF_Undefined = 1U << 0, // Symbol is defined in another object file
SF_Global = 1U << 1, // Global symbol
SF_Weak = 1U << 2, // Weak symbol
SF_Absolute = 1U << 3, // Absolute symbol
SF_ThreadLocal = 1U << 4, // Thread local symbol
SF_Common = 1U << 5, // Symbol has common linkage
SF_FormatSpecific = 1U << 31 // Specific to the object file format
// (e.g. section symbols)
};
SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner);
bool operator==(const SymbolRef &Other) const;
bool operator<(const SymbolRef &Other) const;
error_code getNext(SymbolRef &Result) const;
error_code getName(StringRef &Result) const;
/// Returns the symbol virtual address (i.e. address at which it will be
/// mapped).
error_code getAddress(uint64_t &Result) const;
error_code getFileOffset(uint64_t &Result) const;
/// @brief Get the alignment of this symbol as the actual value (not log 2).
error_code getAlignment(uint32_t &Result) const;
error_code getSize(uint64_t &Result) const;
error_code getType(SymbolRef::Type &Result) const;
/// Returns the ascii char that should be displayed in a symbol table dump via
/// nm for this symbol.
error_code getNMTypeChar(char &Result) const;
/// Get symbol flags (bitwise OR of SymbolRef::Flags)
error_code getFlags(uint32_t &Result) const;
/// @brief Get section this symbol is defined in reference to. Result is
/// end_sections() if it is undefined or is an absolute symbol.
error_code getSection(section_iterator &Result) const;
/// @brief Get value of the symbol in the symbol table.
error_code getValue(uint64_t &Val) const;
DataRefImpl getRawDataRefImpl() const;
};
/// LibraryRef - This is a value type class that represents a single library in
/// the list of libraries needed by a shared or dynamic object.
class LibraryRef {
friend class SectionRef;
DataRefImpl LibraryPimpl;
const ObjectFile *OwningObject;
public:
LibraryRef() : OwningObject(NULL) { }
LibraryRef(DataRefImpl LibraryP, const ObjectFile *Owner);
bool operator==(const LibraryRef &Other) const;
bool operator<(const LibraryRef &Other) const;
error_code getNext(LibraryRef &Result) const;
// Get the path to this library, as stored in the object file.
error_code getPath(StringRef &Result) const;
DataRefImpl getRawDataRefImpl() const;
};
typedef content_iterator<LibraryRef> library_iterator;
const uint64_t UnknownAddressOrSize = ~0ULL;
/// ObjectFile - This class is the base class for all object file types.
/// Concrete instances of this object are created by createObjectFile, which
/// figures out which type to create.
class ObjectFile : public Binary {
virtual void anchor();
ObjectFile() LLVM_DELETED_FUNCTION;
ObjectFile(const ObjectFile &other) LLVM_DELETED_FUNCTION;
protected:
ObjectFile(unsigned int Type, MemoryBuffer *source);
const uint8_t *base() const {
return reinterpret_cast<const uint8_t *>(Data->getBufferStart());
}
// These functions are for SymbolRef to call internally. The main goal of
// this is to allow SymbolRef::SymbolPimpl to point directly to the symbol
// entry in the memory mapped object file. SymbolPimpl cannot contain any
// virtual functions because then it could not point into the memory mapped
// file.
//
// Implementations assume that the DataRefImpl is valid and has not been
// modified externally. It's UB otherwise.
friend class SymbolRef;
virtual error_code getSymbolNext(DataRefImpl Symb, SymbolRef &Res) const = 0;
virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const = 0;
virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const = 0;
virtual error_code getSymbolFileOffset(DataRefImpl Symb, uint64_t &Res)const=0;
virtual error_code getSymbolAlignment(DataRefImpl Symb, uint32_t &Res) const;
virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const = 0;
virtual error_code getSymbolType(DataRefImpl Symb,
SymbolRef::Type &Res) const = 0;
virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const = 0;
virtual error_code getSymbolFlags(DataRefImpl Symb,
uint32_t &Res) const = 0;
virtual error_code getSymbolSection(DataRefImpl Symb,
section_iterator &Res) const = 0;
virtual error_code getSymbolValue(DataRefImpl Symb, uint64_t &Val) const = 0;
// Same as above for SectionRef.
friend class SectionRef;
virtual error_code getSectionNext(DataRefImpl Sec, SectionRef &Res) const = 0;
virtual error_code getSectionName(DataRefImpl Sec, StringRef &Res) const = 0;
virtual error_code getSectionAddress(DataRefImpl Sec, uint64_t &Res) const =0;
virtual error_code getSectionSize(DataRefImpl Sec, uint64_t &Res) const = 0;
virtual error_code getSectionContents(DataRefImpl Sec, StringRef &Res)const=0;
virtual error_code getSectionAlignment(DataRefImpl Sec, uint64_t &Res)const=0;
virtual error_code isSectionText(DataRefImpl Sec, bool &Res) const = 0;
virtual error_code isSectionData(DataRefImpl Sec, bool &Res) const = 0;
virtual error_code isSectionBSS(DataRefImpl Sec, bool &Res) const = 0;
virtual error_code isSectionRequiredForExecution(DataRefImpl Sec,
bool &Res) const = 0;
// A section is 'virtual' if its contents aren't present in the object image.
virtual error_code isSectionVirtual(DataRefImpl Sec, bool &Res) const = 0;
virtual error_code isSectionZeroInit(DataRefImpl Sec, bool &Res) const = 0;
virtual error_code isSectionReadOnlyData(DataRefImpl Sec, bool &Res) const =0;
virtual error_code sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb,
bool &Result) const = 0;
virtual relocation_iterator getSectionRelBegin(DataRefImpl Sec) const = 0;
virtual relocation_iterator getSectionRelEnd(DataRefImpl Sec) const = 0;
virtual section_iterator getRelocatedSection(DataRefImpl Sec) const;
// Same as above for RelocationRef.
friend class RelocationRef;
virtual error_code getRelocationNext(DataRefImpl Rel,
RelocationRef &Res) const = 0;
virtual error_code getRelocationAddress(DataRefImpl Rel,
uint64_t &Res) const =0;
virtual error_code getRelocationOffset(DataRefImpl Rel,
uint64_t &Res) const =0;
virtual symbol_iterator getRelocationSymbol(DataRefImpl Rel) const = 0;
virtual error_code getRelocationType(DataRefImpl Rel,
uint64_t &Res) const = 0;
virtual error_code getRelocationTypeName(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const = 0;
virtual error_code getRelocationValueString(DataRefImpl Rel,
SmallVectorImpl<char> &Result) const = 0;
virtual error_code getRelocationHidden(DataRefImpl Rel, bool &Result) const {
Result = false;
return object_error::success;
}
// Same for LibraryRef
friend class LibraryRef;
virtual error_code getLibraryNext(DataRefImpl Lib, LibraryRef &Res) const = 0;
virtual error_code getLibraryPath(DataRefImpl Lib, StringRef &Res) const = 0;
public:
virtual symbol_iterator begin_symbols() const = 0;
virtual symbol_iterator end_symbols() const = 0;
virtual symbol_iterator begin_dynamic_symbols() const = 0;
virtual symbol_iterator end_dynamic_symbols() const = 0;
virtual section_iterator begin_sections() const = 0;
virtual section_iterator end_sections() const = 0;
virtual library_iterator begin_libraries_needed() const = 0;
virtual library_iterator end_libraries_needed() const = 0;
/// @brief The number of bytes used to represent an address in this object
/// file format.
virtual uint8_t getBytesInAddress() const = 0;
virtual StringRef getFileFormatName() const = 0;
virtual /* Triple::ArchType */ unsigned getArch() const = 0;
/// For shared objects, returns the name which this object should be
/// loaded from at runtime. This corresponds to DT_SONAME on ELF and
/// LC_ID_DYLIB (install name) on MachO.
virtual StringRef getLoadName() const = 0;
/// @returns Pointer to ObjectFile subclass to handle this type of object.
/// @param ObjectPath The path to the object file. ObjectPath.isObject must
/// return true.
/// @brief Create ObjectFile from path.
static ObjectFile *createObjectFile(StringRef ObjectPath);
static ObjectFile *createObjectFile(MemoryBuffer *Object);
static inline bool classof(const Binary *v) {
return v->isObject();
}
public:
static ObjectFile *createCOFFObjectFile(MemoryBuffer *Object);
static ObjectFile *createELFObjectFile(MemoryBuffer *Object);
static ObjectFile *createMachOObjectFile(MemoryBuffer *Object);
};
// Inline function definitions.
inline SymbolRef::SymbolRef(DataRefImpl SymbolP, const ObjectFile *Owner)
: SymbolPimpl(SymbolP)
, OwningObject(Owner) {}
inline bool SymbolRef::operator==(const SymbolRef &Other) const {
return SymbolPimpl == Other.SymbolPimpl;
}
inline bool SymbolRef::operator<(const SymbolRef &Other) const {
return SymbolPimpl < Other.SymbolPimpl;
}
inline error_code SymbolRef::getNext(SymbolRef &Result) const {
return OwningObject->getSymbolNext(SymbolPimpl, Result);
}
inline error_code SymbolRef::getName(StringRef &Result) const {
return OwningObject->getSymbolName(SymbolPimpl, Result);
}
inline error_code SymbolRef::getAddress(uint64_t &Result) const {
return OwningObject->getSymbolAddress(SymbolPimpl, Result);
}
inline error_code SymbolRef::getFileOffset(uint64_t &Result) const {
return OwningObject->getSymbolFileOffset(SymbolPimpl, Result);
}
inline error_code SymbolRef::getAlignment(uint32_t &Result) const {
return OwningObject->getSymbolAlignment(SymbolPimpl, Result);
}
inline error_code SymbolRef::getSize(uint64_t &Result) const {
return OwningObject->getSymbolSize(SymbolPimpl, Result);
}
inline error_code SymbolRef::getNMTypeChar(char &Result) const {
return OwningObject->getSymbolNMTypeChar(SymbolPimpl, Result);
}
inline error_code SymbolRef::getFlags(uint32_t &Result) const {
return OwningObject->getSymbolFlags(SymbolPimpl, Result);
}
inline error_code SymbolRef::getSection(section_iterator &Result) const {
return OwningObject->getSymbolSection(SymbolPimpl, Result);
}
inline error_code SymbolRef::getType(SymbolRef::Type &Result) const {
return OwningObject->getSymbolType(SymbolPimpl, Result);
}
inline error_code SymbolRef::getValue(uint64_t &Val) const {
return OwningObject->getSymbolValue(SymbolPimpl, Val);
}
inline DataRefImpl SymbolRef::getRawDataRefImpl() const {
return SymbolPimpl;
}
/// SectionRef
inline SectionRef::SectionRef(DataRefImpl SectionP,
const ObjectFile *Owner)
: SectionPimpl(SectionP)
, OwningObject(Owner) {}
inline bool SectionRef::operator==(const SectionRef &Other) const {
return SectionPimpl == Other.SectionPimpl;
}
inline bool SectionRef::operator<(const SectionRef &Other) const {
return SectionPimpl < Other.SectionPimpl;
}
inline error_code SectionRef::getNext(SectionRef &Result) const {
return OwningObject->getSectionNext(SectionPimpl, Result);
}
inline error_code SectionRef::getName(StringRef &Result) const {
return OwningObject->getSectionName(SectionPimpl, Result);
}
inline error_code SectionRef::getAddress(uint64_t &Result) const {
return OwningObject->getSectionAddress(SectionPimpl, Result);
}
inline error_code SectionRef::getSize(uint64_t &Result) const {
return OwningObject->getSectionSize(SectionPimpl, Result);
}
inline error_code SectionRef::getContents(StringRef &Result) const {
return OwningObject->getSectionContents(SectionPimpl, Result);
}
inline error_code SectionRef::getAlignment(uint64_t &Result) const {
return OwningObject->getSectionAlignment(SectionPimpl, Result);
}
inline error_code SectionRef::isText(bool &Result) const {
return OwningObject->isSectionText(SectionPimpl, Result);
}
inline error_code SectionRef::isData(bool &Result) const {
return OwningObject->isSectionData(SectionPimpl, Result);
}
inline error_code SectionRef::isBSS(bool &Result) const {
return OwningObject->isSectionBSS(SectionPimpl, Result);
}
inline error_code SectionRef::isRequiredForExecution(bool &Result) const {
return OwningObject->isSectionRequiredForExecution(SectionPimpl, Result);
}
inline error_code SectionRef::isVirtual(bool &Result) const {
return OwningObject->isSectionVirtual(SectionPimpl, Result);
}
inline error_code SectionRef::isZeroInit(bool &Result) const {
return OwningObject->isSectionZeroInit(SectionPimpl, Result);
}
inline error_code SectionRef::isReadOnlyData(bool &Result) const {
return OwningObject->isSectionReadOnlyData(SectionPimpl, Result);
}
inline error_code SectionRef::containsSymbol(SymbolRef S, bool &Result) const {
return OwningObject->sectionContainsSymbol(SectionPimpl, S.SymbolPimpl,
Result);
}
inline relocation_iterator SectionRef::begin_relocations() const {
return OwningObject->getSectionRelBegin(SectionPimpl);
}
inline relocation_iterator SectionRef::end_relocations() const {
return OwningObject->getSectionRelEnd(SectionPimpl);
}
inline section_iterator SectionRef::getRelocatedSection() const {
return OwningObject->getRelocatedSection(SectionPimpl);
}
inline DataRefImpl SectionRef::getRawDataRefImpl() const {
return SectionPimpl;
}
/// RelocationRef
inline RelocationRef::RelocationRef(DataRefImpl RelocationP,
const ObjectFile *Owner)
: RelocationPimpl(RelocationP)
, OwningObject(Owner) {}
inline bool RelocationRef::operator==(const RelocationRef &Other) const {
return RelocationPimpl == Other.RelocationPimpl;
}
inline error_code RelocationRef::getNext(RelocationRef &Result) const {
return OwningObject->getRelocationNext(RelocationPimpl, Result);
}
inline error_code RelocationRef::getAddress(uint64_t &Result) const {
return OwningObject->getRelocationAddress(RelocationPimpl, Result);
}
inline error_code RelocationRef::getOffset(uint64_t &Result) const {
return OwningObject->getRelocationOffset(RelocationPimpl, Result);
}
inline symbol_iterator RelocationRef::getSymbol() const {
return OwningObject->getRelocationSymbol(RelocationPimpl);
}
inline error_code RelocationRef::getType(uint64_t &Result) const {
return OwningObject->getRelocationType(RelocationPimpl, Result);
}
inline error_code RelocationRef::getTypeName(SmallVectorImpl<char> &Result)
const {
return OwningObject->getRelocationTypeName(RelocationPimpl, Result);
}
inline error_code RelocationRef::getValueString(SmallVectorImpl<char> &Result)
const {
return OwningObject->getRelocationValueString(RelocationPimpl, Result);
}
inline error_code RelocationRef::getHidden(bool &Result) const {
return OwningObject->getRelocationHidden(RelocationPimpl, Result);
}
inline DataRefImpl RelocationRef::getRawDataRefImpl() const {
return RelocationPimpl;
}
inline const ObjectFile *RelocationRef::getObjectFile() const {
return OwningObject;
}
// Inline function definitions.
inline LibraryRef::LibraryRef(DataRefImpl LibraryP, const ObjectFile *Owner)
: LibraryPimpl(LibraryP)
, OwningObject(Owner) {}
inline bool LibraryRef::operator==(const LibraryRef &Other) const {
return LibraryPimpl == Other.LibraryPimpl;
}
inline bool LibraryRef::operator<(const LibraryRef &Other) const {
return LibraryPimpl < Other.LibraryPimpl;
}
inline error_code LibraryRef::getNext(LibraryRef &Result) const {
return OwningObject->getLibraryNext(LibraryPimpl, Result);
}
inline error_code LibraryRef::getPath(StringRef &Result) const {
return OwningObject->getLibraryPath(LibraryPimpl, Result);
}
} // end namespace object
} // end namespace llvm
#endif