1 //===- ARM64_32.cpp 2 //----------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "Arch/ARM64Common.h" 11 #include "InputFiles.h" 12 #include "Symbols.h" 13 #include "SyntheticSections.h" 14 #include "Target.h" 15 16 #include "lld/Common/ErrorHandler.h" 17 #include "llvm/ADT/SmallVector.h" 18 #include "llvm/ADT/StringRef.h" 19 #include "llvm/BinaryFormat/MachO.h" 20 #include "llvm/Support/Endian.h" 21 #include "llvm/Support/MathExtras.h" 22 23 using namespace llvm::MachO; 24 using namespace llvm::support::endian; 25 using namespace lld; 26 using namespace lld::macho; 27 28 namespace { 29 30 struct ARM64_32 : ARM64Common { 31 ARM64_32(); 32 void writeStub(uint8_t *buf, const Symbol &, uint64_t) const override; 33 void writeStubHelperHeader(uint8_t *buf) const override; 34 void writeStubHelperEntry(uint8_t *buf, const Symbol &, 35 uint64_t entryAddr) const override; 36 void writeObjCMsgSendStub(uint8_t *buf, Symbol *sym, uint64_t stubsAddr, 37 uint64_t &stubOffset, uint64_t selrefVA, 38 Symbol *objcMsgSend) const override; 39 }; 40 41 } // namespace 42 43 // These are very similar to ARM64's relocation attributes, except that we don't 44 // have the BYTE8 flag set. 45 static constexpr std::array<RelocAttrs, 11> relocAttrsArray{{ 46 #define B(x) RelocAttrBits::x 47 {"UNSIGNED", B(UNSIGNED) | B(ABSOLUTE) | B(EXTERN) | B(LOCAL) | B(BYTE4)}, 48 {"SUBTRACTOR", B(SUBTRAHEND) | B(EXTERN) | B(BYTE4)}, 49 {"BRANCH26", B(PCREL) | B(EXTERN) | B(BRANCH) | B(BYTE4)}, 50 {"PAGE21", B(PCREL) | B(EXTERN) | B(BYTE4)}, 51 {"PAGEOFF12", B(ABSOLUTE) | B(EXTERN) | B(BYTE4)}, 52 {"GOT_LOAD_PAGE21", B(PCREL) | B(EXTERN) | B(GOT) | B(BYTE4)}, 53 {"GOT_LOAD_PAGEOFF12", 54 B(ABSOLUTE) | B(EXTERN) | B(GOT) | B(LOAD) | B(BYTE4)}, 55 {"POINTER_TO_GOT", B(PCREL) | B(EXTERN) | B(GOT) | B(POINTER) | B(BYTE4)}, 56 {"TLVP_LOAD_PAGE21", B(PCREL) | B(EXTERN) | B(TLV) | B(BYTE4)}, 57 {"TLVP_LOAD_PAGEOFF12", 58 B(ABSOLUTE) | B(EXTERN) | B(TLV) | B(LOAD) | B(BYTE4)}, 59 {"ADDEND", B(ADDEND)}, 60 #undef B 61 }}; 62 63 // The stub code is fairly similar to ARM64's, except that we load pointers into 64 // 32-bit 'w' registers, instead of the 64-bit 'x' ones. 65 66 static constexpr uint32_t stubCode[] = { 67 0x90000010, // 00: adrp x16, __la_symbol_ptr@page 68 0xb9400210, // 04: ldr w16, [x16, __la_symbol_ptr@pageoff] 69 0xd61f0200, // 08: br x16 70 }; 71 72 void ARM64_32::writeStub(uint8_t *buf8, const Symbol &sym, 73 uint64_t pointerVA) const { 74 ::writeStub(buf8, stubCode, sym, pointerVA); 75 } 76 77 static constexpr uint32_t stubHelperHeaderCode[] = { 78 0x90000011, // 00: adrp x17, _dyld_private@page 79 0x91000231, // 04: add x17, x17, _dyld_private@pageoff 80 0xa9bf47f0, // 08: stp x16/x17, [sp, #-16]! 81 0x90000010, // 0c: adrp x16, dyld_stub_binder@page 82 0xb9400210, // 10: ldr w16, [x16, dyld_stub_binder@pageoff] 83 0xd61f0200, // 14: br x16 84 }; 85 86 void ARM64_32::writeStubHelperHeader(uint8_t *buf8) const { 87 ::writeStubHelperHeader<ILP32>(buf8, stubHelperHeaderCode); 88 } 89 90 static constexpr uint32_t stubHelperEntryCode[] = { 91 0x18000050, // 00: ldr w16, l0 92 0x14000000, // 04: b stubHelperHeader 93 0x00000000, // 08: l0: .long 0 94 }; 95 96 void ARM64_32::writeStubHelperEntry(uint8_t *buf8, const Symbol &sym, 97 uint64_t entryVA) const { 98 ::writeStubHelperEntry(buf8, stubHelperEntryCode, sym, entryVA); 99 } 100 101 void ARM64_32::writeObjCMsgSendStub(uint8_t *buf, Symbol *sym, 102 uint64_t stubsAddr, uint64_t &stubOffset, 103 uint64_t selrefVA, 104 Symbol *objcMsgSend) const { 105 fatal("TODO: implement this"); 106 } 107 108 ARM64_32::ARM64_32() : ARM64Common(ILP32()) { 109 cpuType = CPU_TYPE_ARM64_32; 110 cpuSubtype = CPU_SUBTYPE_ARM64_V8; 111 112 modeDwarfEncoding = 0x04000000; // UNWIND_ARM_MODE_DWARF 113 subtractorRelocType = GENERIC_RELOC_INVALID; // FIXME 114 unsignedRelocType = GENERIC_RELOC_INVALID; // FIXME 115 116 stubSize = sizeof(stubCode); 117 stubHelperHeaderSize = sizeof(stubHelperHeaderCode); 118 stubHelperEntrySize = sizeof(stubHelperEntryCode); 119 120 relocAttrs = {relocAttrsArray.data(), relocAttrsArray.size()}; 121 } 122 123 TargetInfo *macho::createARM64_32TargetInfo() { 124 static ARM64_32 t; 125 return &t; 126 } 127