| //===- 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 { |
| namespace 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; } |
| }; |
| |
| inline uint64_t bitField(uint64_t value, int right, int width, int left) { |
| return ((value >> right) & ((1 << width) - 1)) << left; |
| } |
| |
| // 25 0 |
| // +-----------+---------------------------------------------------+ |
| // | | imm26 | |
| // +-----------+---------------------------------------------------+ |
| |
| inline uint64_t encodeBranch26(const Reloc &r, uint64_t base, uint64_t va) { |
| checkInt(r, va, 28); |
| // Since branch destinations are 4-byte aligned, the 2 least- |
| // significant bits are 0. They are right shifted off the end. |
| return (base | bitField(va, 2, 26, 0)); |
| } |
| |
| inline uint64_t encodeBranch26(SymbolDiagnostic d, uint64_t base, uint64_t va) { |
| checkInt(d, va, 28); |
| return (base | bitField(va, 2, 26, 0)); |
| } |
| |
| // 30 29 23 5 |
| // +-+---+---------+-------------------------------------+---------+ |
| // | |ilo| | immhi | | |
| // +-+---+---------+-------------------------------------+---------+ |
| |
| inline uint64_t encodePage21(const Reloc &r, uint64_t base, uint64_t va) { |
| checkInt(r, va, 35); |
| return (base | bitField(va, 12, 2, 29) | bitField(va, 14, 19, 5)); |
| } |
| |
| inline uint64_t encodePage21(SymbolDiagnostic d, uint64_t base, uint64_t va) { |
| checkInt(d, va, 35); |
| return (base | bitField(va, 12, 2, 29) | bitField(va, 14, 19, 5)); |
| } |
| |
| // 21 10 |
| // +-------------------+-----------------------+-------------------+ |
| // | | imm12 | | |
| // +-------------------+-----------------------+-------------------+ |
| |
| inline uint64_t encodePageOff12(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; |
| } |
| |
| // TODO(gkm): extract embedded addend and warn if != 0 |
| // uint64_t addend = ((base & 0x003FFC00) >> 10); |
| return (base | bitField(va, scale, 12 - scale, 10)); |
| } |
| |
| inline uint64_t pageBits(uint64_t address) { |
| const uint64_t pageMask = ~0xfffull; |
| return address & pageMask; |
| } |
| |
| template <class LP> |
| inline void writeStub(uint8_t *buf8, const uint32_t stubCode[3], |
| const macho::Symbol &sym) { |
| auto *buf32 = reinterpret_cast<uint32_t *>(buf8); |
| constexpr size_t stubCodeSize = 3 * sizeof(uint32_t); |
| uint64_t pcPageBits = |
| pageBits(in.stubs->addr + sym.stubsIndex * stubCodeSize); |
| uint64_t lazyPointerVA = |
| in.lazyPointers->addr + sym.stubsIndex * LP::wordSize; |
| buf32[0] = encodePage21({&sym, "stub"}, stubCode[0], |
| pageBits(lazyPointerVA) - pcPageBits); |
| buf32[1] = encodePageOff12(stubCode[1], lazyPointerVA); |
| 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"}; |
| buf32[0] = encodePage21(d, stubHelperHeaderCode[0], |
| pageBits(loaderVA) - pcPageBits(0)); |
| buf32[1] = encodePageOff12(stubHelperHeaderCode[1], loaderVA); |
| buf32[2] = stubHelperHeaderCode[2]; |
| uint64_t binderVA = |
| in.got->addr + in.stubHelper->stubBinder->gotIndex * LP::wordSize; |
| buf32[3] = encodePage21(d, stubHelperHeaderCode[3], |
| pageBits(binderVA) - pcPageBits(3)); |
| buf32[4] = encodePageOff12(stubHelperHeaderCode[4], binderVA); |
| buf32[5] = stubHelperHeaderCode[5]; |
| } |
| |
| inline void writeStubHelperEntry(uint8_t *buf8, |
| const uint32_t stubHelperEntryCode[3], |
| const DylibSymbol &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]; |
| buf32[1] = encodeBranch26({&sym, "stub helper"}, stubHelperEntryCode[1], |
| stubHelperHeaderVA - pcVA(1)); |
| buf32[2] = sym.lazyBindOffset; |
| } |
| |
| } // namespace macho |
| } // namespace lld |
| |
| #endif |