llvm-project/llvm/lib/Target/BPF/MCTargetDesc/BPFELFObjectWriter.cpp

62 lines
1.9 KiB
C++

//===-- BPFELFObjectWriter.cpp - BPF ELF Writer ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "MCTargetDesc/BPFMCTargetDesc.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/Support/ErrorHandling.h"
#include <cstdint>
using namespace llvm;
namespace {
class BPFELFObjectWriter : public MCELFObjectTargetWriter {
public:
BPFELFObjectWriter(uint8_t OSABI);
~BPFELFObjectWriter() override = default;
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
};
} // end anonymous namespace
BPFELFObjectWriter::BPFELFObjectWriter(uint8_t OSABI)
: MCELFObjectTargetWriter(/*Is64Bit*/ true, OSABI, ELF::EM_BPF,
/*HasRelocationAddend*/ false) {}
unsigned BPFELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
// determine the type of the relocation
switch ((unsigned)Fixup.getKind()) {
default:
llvm_unreachable("invalid fixup kind!");
case FK_SecRel_8:
return ELF::R_BPF_64_64;
case FK_SecRel_4:
return ELF::R_BPF_64_32;
case FK_Data_8:
return ELF::R_BPF_64_64;
case FK_Data_4:
return ELF::R_BPF_64_32;
}
}
std::unique_ptr<MCObjectWriter>
llvm::createBPFELFObjectWriter(raw_pwrite_stream &OS, uint8_t OSABI,
bool IsLittleEndian) {
return createELFObjectWriter(llvm::make_unique<BPFELFObjectWriter>(OSABI), OS,
IsLittleEndian);
}