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//===- ARM64Common.h --------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLD_MACHO_ARCH_ARM64COMMON_H
#define LLD_MACHO_ARCH_ARM64COMMON_H
#include "InputFiles.h"
#include "Symbols.h"
#include "SyntheticSections.h"
#include "Target.h"
#include "llvm/BinaryFormat/MachO.h"
namespace lld::macho {
struct ARM64Common : TargetInfo {
template <class LP> ARM64Common(LP lp) : TargetInfo(lp) {}
int64_t getEmbeddedAddend(MemoryBufferRef, uint64_t offset,
const llvm::MachO::relocation_info) const override;
void relocateOne(uint8_t *loc, const Reloc &, uint64_t va,
uint64_t pc) const override;
void relaxGotLoad(uint8_t *loc, uint8_t type) const override;
uint64_t getPageSize() const override { return 16 * 1024; }
void handleDtraceReloc(const Symbol *sym, const Reloc &r,
uint8_t *loc) const override;
};
inline uint64_t bitField(uint64_t value, int right, int width, int left) {
return ((value >> right) & ((1 << width) - 1)) << left;
}
// 25 0
// +-----------+---------------------------------------------------+
// | | imm26 |
// +-----------+---------------------------------------------------+
inline void encodeBranch26(uint32_t *loc, const Reloc &r, uint32_t base,
uint64_t va) {
checkInt(loc, r, va, 28);
// Since branch destinations are 4-byte aligned, the 2 least-
// significant bits are 0. They are right shifted off the end.
llvm::support::endian::write32le(loc, base | bitField(va, 2, 26, 0));
}
inline void encodeBranch26(uint32_t *loc, SymbolDiagnostic d, uint32_t base,
uint64_t va) {
checkInt(loc, d, va, 28);
llvm::support::endian::write32le(loc, base | bitField(va, 2, 26, 0));
}
// 30 29 23 5
// +-+---+---------+-------------------------------------+---------+
// | |ilo| | immhi | |
// +-+---+---------+-------------------------------------+---------+
inline void encodePage21(uint32_t *loc, const Reloc &r, uint32_t base,
uint64_t va) {
checkInt(loc, r, va, 35);
llvm::support::endian::write32le(loc, base | bitField(va, 12, 2, 29) |
bitField(va, 14, 19, 5));
}
inline void encodePage21(uint32_t *loc, SymbolDiagnostic d, uint32_t base,
uint64_t va) {
checkInt(loc, d, va, 35);
llvm::support::endian::write32le(loc, base | bitField(va, 12, 2, 29) |
bitField(va, 14, 19, 5));
}
void reportUnalignedLdrStr(void *loc, const Reloc &, uint64_t va, int align);
void reportUnalignedLdrStr(void *loc, SymbolDiagnostic, uint64_t va, int align);
// 21 10
// +-------------------+-----------------------+-------------------+
// | | imm12 | |
// +-------------------+-----------------------+-------------------+
template <typename Target>
inline void encodePageOff12(uint32_t *loc, Target t, uint32_t base,
uint64_t va) {
int scale = 0;
if ((base & 0x3b00'0000) == 0x3900'0000) { // load/store
scale = base >> 30;
if (scale == 0 && (base & 0x0480'0000) == 0x0480'0000) // 128-bit variant
scale = 4;
}
const int size = 1 << scale;
if ((va & (size - 1)) != 0)
reportUnalignedLdrStr(loc, t, va, size);
// TODO(gkm): extract embedded addend and warn if != 0
// uint64_t addend = ((base & 0x003FFC00) >> 10);
llvm::support::endian::write32le(loc,
base | bitField(va, scale, 12 - scale, 10));
}
inline uint64_t pageBits(uint64_t address) {
const uint64_t pageMask = ~0xfffull;
return address & pageMask;
}
inline void writeStub(uint8_t *buf8, const uint32_t stubCode[3],
const macho::Symbol &sym, uint64_t pointerVA) {
auto *buf32 = reinterpret_cast<uint32_t *>(buf8);
constexpr size_t stubCodeSize = 3 * sizeof(uint32_t);
SymbolDiagnostic d = {&sym, "stub"};
uint64_t pcPageBits =
pageBits(in.stubs->addr + sym.stubsIndex * stubCodeSize);
encodePage21(&buf32[0], d, stubCode[0], pageBits(pointerVA) - pcPageBits);
encodePageOff12(&buf32[1], d, stubCode[1], pointerVA);
buf32[2] = stubCode[2];
}
template <class LP>
inline void writeStubHelperHeader(uint8_t *buf8,
const uint32_t stubHelperHeaderCode[6]) {
auto *buf32 = reinterpret_cast<uint32_t *>(buf8);
auto pcPageBits = [](int i) {
return pageBits(in.stubHelper->addr + i * sizeof(uint32_t));
};
uint64_t loaderVA = in.imageLoaderCache->getVA();
SymbolDiagnostic d = {nullptr, "stub header helper"};
encodePage21(&buf32[0], d, stubHelperHeaderCode[0],
pageBits(loaderVA) - pcPageBits(0));
encodePageOff12(&buf32[1], d, stubHelperHeaderCode[1], loaderVA);
buf32[2] = stubHelperHeaderCode[2];
uint64_t binderVA =
in.got->addr + in.stubHelper->stubBinder->gotIndex * LP::wordSize;
encodePage21(&buf32[3], d, stubHelperHeaderCode[3],
pageBits(binderVA) - pcPageBits(3));
encodePageOff12(&buf32[4], d, stubHelperHeaderCode[4], binderVA);
buf32[5] = stubHelperHeaderCode[5];
}
inline void writeStubHelperEntry(uint8_t *buf8,
const uint32_t stubHelperEntryCode[3],
const Symbol &sym, uint64_t entryVA) {
auto *buf32 = reinterpret_cast<uint32_t *>(buf8);
auto pcVA = [entryVA](int i) { return entryVA + i * sizeof(uint32_t); };
uint64_t stubHelperHeaderVA = in.stubHelper->addr;
buf32[0] = stubHelperEntryCode[0];
encodeBranch26(&buf32[1], {&sym, "stub helper"}, stubHelperEntryCode[1],
stubHelperHeaderVA - pcVA(1));
buf32[2] = sym.lazyBindOffset;
}
template <class LP>
inline void
writeObjCMsgSendStub(uint8_t *buf, const uint32_t objcStubsFastCode[8],
Symbol *sym, uint64_t stubsAddr, uint64_t stubOffset,
uint64_t selrefsVA, uint64_t selectorIndex,
uint64_t gotAddr, uint64_t msgSendIndex) {
SymbolDiagnostic d = {sym, sym->getName()};
auto *buf32 = reinterpret_cast<uint32_t *>(buf);
auto pcPageBits = [stubsAddr, stubOffset](int i) {
return pageBits(stubsAddr + stubOffset + i * sizeof(uint32_t));
};
uint64_t selectorOffset = selectorIndex * LP::wordSize;
encodePage21(&buf32[0], d, objcStubsFastCode[0],
pageBits(selrefsVA + selectorOffset) - pcPageBits(0));
encodePageOff12(&buf32[1], d, objcStubsFastCode[1],
selrefsVA + selectorOffset);
encodePage21(&buf32[2], d, objcStubsFastCode[2],
pageBits(gotAddr) - pcPageBits(2));
encodePage21(&buf32[3], d, objcStubsFastCode[3], msgSendIndex * LP::wordSize);
buf32[4] = objcStubsFastCode[4];
buf32[5] = objcStubsFastCode[5];
buf32[6] = objcStubsFastCode[6];
buf32[7] = objcStubsFastCode[7];
}
} // namespace lld::macho
#endif
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