llvm-project/lld/lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.cpp

331 lines
10 KiB
C++

//===- lib/ReaderWriter/ELF/Hexagon/HexagonRelocationHandler.cpp ---------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "HexagonEncodings.h"
#include "HexagonLinkingContext.h"
#include "HexagonRelocationHandler.h"
#include "HexagonTargetHandler.h"
#include "llvm/Support/Endian.h"
using namespace lld;
using namespace lld::elf;
using namespace llvm::ELF;
using namespace llvm::support::endian;
// Scatter val's bits as specified by the mask. Example:
//
// Val: 0bABCDEFG
// Mask: 0b10111100001011
// Output: 0b00ABCD0000E0FG
static uint32_t scatterBits(uint32_t val, uint32_t mask) {
uint32_t result = 0;
size_t off = 0;
for (size_t bit = 0; bit < 32; ++bit) {
if ((mask >> bit) & 1) {
uint32_t valBit = (val >> off) & 1;
result |= valBit << bit;
++off;
}
}
return result;
}
static void relocBNPCREL(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A,
int32_t nBits) {
int32_t result = (S + A - P) >> 2;
int32_t range = 1 << nBits;
if (result < range && result > -range) {
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
}
/// \brief Word32_LO: 0x00c03fff : (S + A) : Truncate
static void relocLO16(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
uint32_t result = S + A;
result = scatterBits(result, 0x00c03fff);
write32le(loc, result | read32le(loc));
}
/// \brief Word32_LO: 0x00c03fff : (S + A) >> 16 : Truncate
static void relocHI16(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
uint32_t result = (S + A) >> 16;
result = scatterBits(result, 0x00c03fff);
write32le(loc, result | read32le(loc));
}
/// \brief Word32: 0xffffffff : (S + A) : Truncate
static void reloc32(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
uint32_t result = S + A;
write32le(loc, result | read32le(loc));
}
static void reloc32_6_X(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
int64_t result = (S + A) >> 6;
int64_t range = int64_t(1) << 32;
if (result > range)
result = scatterBits(result, 0xfff3fff);
write32le(loc, result | read32le(loc));
}
// R_HEX_B32_PCREL_X
static void relocHexB32PCRELX(uint8_t *loc, uint64_t P, uint64_t S,
uint64_t A) {
int64_t result = (S + A - P) >> 6;
result = scatterBits(result, 0xfff3fff);
write32le(loc, result | read32le(loc));
}
// R_HEX_BN_PCREL_X
static void relocHexBNPCRELX(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A,
int nbits) {
int32_t result = (S + A - P) & 0x3f;
int32_t range = 1 << nbits;
if (result < range && result > -range) {
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
}
// R_HEX_6_PCREL_X
static void relocHex6PCRELX(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
int32_t result = S + A - P;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
// R_HEX_N_X : Word32_U6 : (S + A) : Unsigned Truncate
static void relocHex_N_X(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A) {
uint32_t result = S + A;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
// GP REL relocs
static void relocHexGPRELN(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A,
uint64_t GP, int nShiftBits) {
int32_t result = (S + A - GP) >> nShiftBits;
int32_t range = 1L << 16;
if (result <= range) {
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
}
/// \brief Word32_LO: 0x00c03fff : (G) : Truncate
static void relocHexGOTLO16(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = A - GOT;
result = scatterBits(result, 0x00c03fff);
write32le(loc, result | read32le(loc));
}
/// \brief Word32_LO: 0x00c03fff : (G) >> 16 : Truncate
static void relocHexGOTHI16(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = (A - GOT) >> 16;
result = scatterBits(result, 0x00c03fff);
write32le(loc, result | read32le(loc));
}
/// \brief Word32: 0xffffffff : (G) : Truncate
static void relocHexGOT32(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = GOT - A;
write32le(loc, result | read32le(loc));
}
/// \brief Word32_U16 : (G) : Truncate
static void relocHexGOT16(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = GOT - A;
int32_t range = 1L << 16;
if (result <= range) {
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
}
static void relocHexGOT32_6_X(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = (A - GOT) >> 6;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
static void relocHexGOT16_X(uint8_t *loc, uint64_t A, uint64_t GOT) {
int32_t result = A - GOT;
int32_t range = 1L << 6;
if (result <= range) {
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
}
static void relocHexGOT11_X(uint8_t *loc, uint64_t A, uint64_t GOT) {
uint32_t result = A - GOT;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
static void relocHexGOTRELSigned(uint8_t *loc, uint64_t P, uint64_t S,
uint64_t A, uint64_t GOT, int shiftBits) {
int32_t result = (S + A - GOT) >> shiftBits;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
static void relocHexGOTRELUnsigned(uint8_t *loc, uint64_t P, uint64_t S,
uint64_t A, uint64_t GOT) {
uint32_t result = S + A - GOT;
result = scatterBits(result, findv4bitmask(loc));
write32le(loc, result | read32le(loc));
}
static void relocHexGOTREL_HILO16(uint8_t *loc, uint64_t P, uint64_t S,
uint64_t A, uint64_t GOT, int shiftBits) {
int32_t result = (S + A - GOT) >> shiftBits;
result = scatterBits(result, 0x00c03fff);
write32le(loc, result | read32le(loc));
}
static void relocHexGOTREL_32(uint8_t *loc, uint64_t P, uint64_t S, uint64_t A,
uint64_t GOT) {
int32_t result = S + A - GOT;
write32le(loc, result | read32le(loc));
}
std::error_code HexagonTargetRelocationHandler::applyRelocation(
ELFWriter &writer, llvm::FileOutputBuffer &buf, const AtomLayout &atom,
const Reference &ref) const {
uint8_t *atomContent = buf.getBufferStart() + atom._fileOffset;
uint8_t *loc = atomContent + ref.offsetInAtom();
uint64_t target = writer.addressOfAtom(ref.target());
uint64_t reloc = atom._virtualAddr + ref.offsetInAtom();
if (ref.kindNamespace() != Reference::KindNamespace::ELF)
return std::error_code();
assert(ref.kindArch() == Reference::KindArch::Hexagon);
switch (ref.kindValue()) {
case R_HEX_B22_PCREL:
relocBNPCREL(loc, reloc, target, ref.addend(), 21);
break;
case R_HEX_B15_PCREL:
relocBNPCREL(loc, reloc, target, ref.addend(), 14);
break;
case R_HEX_B9_PCREL:
relocBNPCREL(loc, reloc, target, ref.addend(), 8);
break;
case R_HEX_LO16:
relocLO16(loc, reloc, target, ref.addend());
break;
case R_HEX_HI16:
relocHI16(loc, reloc, target, ref.addend());
break;
case R_HEX_32:
reloc32(loc, reloc, target, ref.addend());
break;
case R_HEX_32_6_X:
reloc32_6_X(loc, reloc, target, ref.addend());
break;
case R_HEX_B32_PCREL_X:
relocHexB32PCRELX(loc, reloc, target, ref.addend());
break;
case R_HEX_B22_PCREL_X:
relocHexBNPCRELX(loc, reloc, target, ref.addend(), 21);
break;
case R_HEX_B15_PCREL_X:
relocHexBNPCRELX(loc, reloc, target, ref.addend(), 14);
break;
case R_HEX_B13_PCREL_X:
relocHexBNPCRELX(loc, reloc, target, ref.addend(), 12);
break;
case R_HEX_B9_PCREL_X:
relocHexBNPCRELX(loc, reloc, target, ref.addend(), 8);
break;
case R_HEX_B7_PCREL_X:
relocHexBNPCRELX(loc, reloc, target, ref.addend(), 6);
break;
case R_HEX_GPREL16_0:
relocHexGPRELN(loc, reloc, target, ref.addend(),
_targetLayout.getSDataSection()->virtualAddr(), 0);
break;
case R_HEX_GPREL16_1:
relocHexGPRELN(loc, reloc, target, ref.addend(),
_targetLayout.getSDataSection()->virtualAddr(), 1);
break;
case R_HEX_GPREL16_2:
relocHexGPRELN(loc, reloc, target, ref.addend(),
_targetLayout.getSDataSection()->virtualAddr(), 2);
break;
case R_HEX_GPREL16_3:
relocHexGPRELN(loc, reloc, target, ref.addend(),
_targetLayout.getSDataSection()->virtualAddr(), 3);
break;
case R_HEX_16_X:
case R_HEX_12_X:
case R_HEX_11_X:
case R_HEX_10_X:
case R_HEX_9_X:
case R_HEX_8_X:
case R_HEX_7_X:
case R_HEX_6_X:
relocHex_N_X(loc, reloc, target, ref.addend());
break;
case R_HEX_6_PCREL_X:
relocHex6PCRELX(loc, reloc, target, ref.addend());
break;
case R_HEX_JMP_SLOT:
case R_HEX_GLOB_DAT:
break;
case R_HEX_GOTREL_32:
relocHexGOTREL_32(loc, reloc, target, ref.addend(),
_targetLayout.getGOTSymAddr());
break;
case R_HEX_GOTREL_LO16:
relocHexGOTREL_HILO16(loc, reloc, target, ref.addend(),
_targetLayout.getGOTSymAddr(), 0);
break;
case R_HEX_GOTREL_HI16:
relocHexGOTREL_HILO16(loc, reloc, target, ref.addend(),
_targetLayout.getGOTSymAddr(), 16);
break;
case R_HEX_GOT_LO16:
relocHexGOTLO16(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_HI16:
relocHexGOTHI16(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_32:
relocHexGOT32(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_16:
relocHexGOT16(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_32_6_X:
relocHexGOT32_6_X(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_16_X:
relocHexGOT16_X(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOT_11_X:
relocHexGOT11_X(loc, target, _targetLayout.getGOTSymAddr());
break;
case R_HEX_GOTREL_32_6_X:
relocHexGOTRELSigned(loc, reloc, target, ref.addend(),
_targetLayout.getGOTSymAddr(), 6);
break;
case R_HEX_GOTREL_16_X:
case R_HEX_GOTREL_11_X:
relocHexGOTRELUnsigned(loc, reloc, target, ref.addend(),
_targetLayout.getGOTSymAddr());
break;
default:
return make_unhandled_reloc_error();
}
return std::error_code();
}