| //===- Target.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_TARGET_H |
| #define LLD_MACHO_TARGET_H |
| |
| #include "llvm/ADT/BitmaskEnum.h" |
| #include "llvm/BinaryFormat/MachO.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| |
| #include <cstddef> |
| #include <cstdint> |
| |
| namespace lld { |
| namespace macho { |
| LLVM_ENABLE_BITMASK_ENUMS_IN_NAMESPACE(); |
| |
| class Symbol; |
| class DylibSymbol; |
| class InputSection; |
| struct Reloc; |
| |
| enum : uint64_t { |
| // We are currently only supporting 64-bit targets since macOS and iOS are |
| // deprecating 32-bit apps. |
| WordSize = 8, |
| PageZeroSize = 1ull << 32, // XXX should be 4096 for 32-bit targets |
| MaxAlignmentPowerOf2 = 32, |
| }; |
| |
| enum class RelocAttrBits { |
| _0 = 0, // invalid |
| PCREL = 1 << 0, // Value is PC-relative offset |
| ABSOLUTE = 1 << 1, // Value is an absolute address or fixed offset |
| BYTE4 = 1 << 2, // 4 byte datum |
| BYTE8 = 1 << 3, // 8 byte datum |
| EXTERN = 1 << 4, // Can have an external symbol |
| LOCAL = 1 << 5, // Can have a local symbol |
| ADDEND = 1 << 6, // *_ADDEND paired prefix reloc |
| SUBTRAHEND = 1 << 7, // *_SUBTRACTOR paired prefix reloc |
| BRANCH = 1 << 8, // Value is branch target |
| GOT = 1 << 9, // References a symbol in the Global Offset Table |
| TLV = 1 << 10, // References a thread-local symbol |
| DYSYM8 = 1 << 11, // Requires DySym width to be 8 bytes |
| LOAD = 1 << 12, // Relaxable indirect load |
| POINTER = 1 << 13, // Non-relaxable indirect load (pointer is taken) |
| UNSIGNED = 1 << 14, // *_UNSIGNED relocs |
| LLVM_MARK_AS_BITMASK_ENUM(/*LargestValue*/ (1 << 15) - 1), |
| }; |
| // Note: SUBTRACTOR always pairs with UNSIGNED (a delta between two symbols). |
| |
| class TargetInfo { |
| public: |
| struct RelocAttrs { |
| llvm::StringRef name; |
| RelocAttrBits bits; |
| bool hasAttr(RelocAttrBits b) const { return (bits & b) == b; } |
| }; |
| static const RelocAttrs invalidRelocAttrs; |
| |
| virtual ~TargetInfo() = default; |
| |
| // Validate the relocation structure and get its addend. |
| virtual uint64_t |
| getEmbeddedAddend(llvm::MemoryBufferRef, const llvm::MachO::section_64 &, |
| const llvm::MachO::relocation_info) const = 0; |
| virtual void relocateOne(uint8_t *loc, const Reloc &, uint64_t va, |
| uint64_t pc) const = 0; |
| |
| // Write code for lazy binding. See the comments on StubsSection for more |
| // details. |
| virtual void writeStub(uint8_t *buf, const Symbol &) const = 0; |
| virtual void writeStubHelperHeader(uint8_t *buf) const = 0; |
| virtual void writeStubHelperEntry(uint8_t *buf, const DylibSymbol &, |
| uint64_t entryAddr) const = 0; |
| |
| // Symbols may be referenced via either the GOT or the stubs section, |
| // depending on the relocation type. prepareSymbolRelocation() will set up the |
| // GOT/stubs entries, and resolveSymbolVA() will return the addresses of those |
| // entries. resolveSymbolVA() may also relax the target instructions to save |
| // on a level of address indirection. |
| virtual void relaxGotLoad(uint8_t *loc, uint8_t type) const = 0; |
| |
| virtual const RelocAttrs &getRelocAttrs(uint8_t type) const = 0; |
| |
| virtual uint64_t getPageSize() const = 0; |
| |
| bool hasAttr(uint8_t type, RelocAttrBits bit) const { |
| return getRelocAttrs(type).hasAttr(bit); |
| } |
| |
| bool validateRelocationInfo(llvm::MemoryBufferRef, |
| const llvm::MachO::section_64 &sec, |
| llvm::MachO::relocation_info); |
| bool validateSymbolRelocation(const Symbol *, const InputSection *isec, |
| const Reloc &); |
| void prepareSymbolRelocation(Symbol *, const InputSection *, const Reloc &); |
| |
| uint32_t cpuType; |
| uint32_t cpuSubtype; |
| |
| size_t stubSize; |
| size_t stubHelperHeaderSize; |
| size_t stubHelperEntrySize; |
| }; |
| |
| TargetInfo *createX86_64TargetInfo(); |
| TargetInfo *createARM64TargetInfo(); |
| |
| extern TargetInfo *target; |
| |
| } // namespace macho |
| } // namespace lld |
| |
| #endif |