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