llvm-project/lld/ELF/Target.h

108 lines
4.2 KiB
C++

//===- Target.h -------------------------------------------------*- C++ -*-===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLD_ELF_TARGET_H
#define LLD_ELF_TARGET_H
#include "llvm/ADT/StringRef.h"
#include "llvm/Object/ELF.h"
#include <memory>
namespace lld {
namespace elf2 {
class SymbolBody;
class TargetInfo {
public:
unsigned getPageSize() const { return PageSize; }
uint64_t getVAStart() const;
unsigned getCopyReloc() const { return CopyReloc; }
unsigned getGotReloc() const { return GotReloc; }
unsigned getPltReloc() const { return PltReloc; }
unsigned getRelativeReloc() const { return RelativeReloc; }
unsigned getTlsGotReloc() const { return TlsGotReloc; }
bool isTlsLocalDynamicReloc(unsigned Type) const {
return Type == TlsLocalDynamicReloc;
}
bool isTlsGlobalDynamicReloc(unsigned Type) const {
return Type == TlsGlobalDynamicReloc;
}
unsigned getTlsModuleIndexReloc() const { return TlsModuleIndexReloc; }
unsigned getTlsOffsetReloc() const { return TlsOffsetReloc; }
unsigned getPltZeroEntrySize() const { return PltZeroEntrySize; }
unsigned getPltEntrySize() const { return PltEntrySize; }
bool supportsLazyRelocations() const { return LazyRelocations; }
unsigned getGotHeaderEntriesNum() const { return GotHeaderEntriesNum; }
unsigned getGotPltHeaderEntriesNum() const { return GotPltHeaderEntriesNum; }
virtual unsigned getDynReloc(unsigned Type) const { return Type; }
virtual bool isTlsDynReloc(unsigned Type) const { return false; }
virtual unsigned getPltRefReloc(unsigned Type) const;
virtual void writeGotHeaderEntries(uint8_t *Buf) const;
virtual void writeGotPltHeaderEntries(uint8_t *Buf) const;
virtual void writeGotPltEntry(uint8_t *Buf, uint64_t Plt) const = 0;
virtual void writePltZeroEntry(uint8_t *Buf, uint64_t GotEntryAddr,
uint64_t PltEntryAddr) const = 0;
virtual void writePltEntry(uint8_t *Buf, uint64_t GotAddr,
uint64_t GotEntryAddr, uint64_t PltEntryAddr,
int32_t Index, unsigned RelOff) const = 0;
virtual bool isRelRelative(uint32_t Type) const;
virtual bool isSizeDynReloc(uint32_t Type, const SymbolBody &S) const;
virtual bool relocNeedsCopy(uint32_t Type, const SymbolBody &S) const;
virtual bool relocNeedsGot(uint32_t Type, const SymbolBody &S) const = 0;
virtual bool relocNeedsPlt(uint32_t Type, const SymbolBody &S) const = 0;
virtual void relocateOne(uint8_t *Loc, uint8_t *BufEnd, uint32_t Type,
uint64_t P, uint64_t SA, uint64_t ZA = 0,
uint8_t *PairedLoc = nullptr) const = 0;
virtual bool isTlsOptimized(unsigned Type, const SymbolBody *S) const;
virtual unsigned relocateTlsOptimize(uint8_t *Loc, uint8_t *BufEnd,
uint32_t Type, uint64_t P, uint64_t SA,
const SymbolBody &S) const;
virtual ~TargetInfo();
protected:
unsigned PageSize = 4096;
// On freebsd x86_64 the first page cannot be mmaped.
// On linux that is controled by vm.mmap_min_addr. At least on some x86_64
// installs that is 65536, so the first 15 pages cannot be used.
// Given that, the smallest value that can be used in here is 0x10000.
// If using 2MB pages, the smallest page aligned address that works is
// 0x200000, but it looks like every OS uses 4k pages for executables.
uint64_t VAStart = 0x10000;
unsigned CopyReloc;
unsigned PCRelReloc;
unsigned GotReloc;
unsigned PltReloc;
unsigned RelativeReloc;
unsigned TlsGotReloc = 0;
unsigned TlsLocalDynamicReloc = 0;
unsigned TlsGlobalDynamicReloc = 0;
unsigned TlsModuleIndexReloc;
unsigned TlsOffsetReloc;
unsigned PltEntrySize = 8;
unsigned PltZeroEntrySize = 0;
unsigned GotHeaderEntriesNum = 0;
unsigned GotPltHeaderEntriesNum = 3;
bool LazyRelocations = false;
};
uint64_t getPPC64TocBase();
template <class ELFT>
typename llvm::object::ELFFile<ELFT>::uintX_t getMipsGpAddr();
extern std::unique_ptr<TargetInfo> Target;
TargetInfo *createTarget();
}
}
#endif