1 | //===---- MachO_x86_64.cpp -JIT linker implementation for MachO/x86-64 ----===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // MachO/x86-64 jit-link implementation. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #include "llvm/ExecutionEngine/JITLink/MachO_x86_64.h" |
14 | #include "llvm/ExecutionEngine/JITLink/DWARFRecordSectionSplitter.h" |
15 | #include "llvm/ExecutionEngine/JITLink/x86_64.h" |
16 | |
17 | #include "MachOLinkGraphBuilder.h" |
18 | |
19 | #define DEBUG_TYPE "jitlink" |
20 | |
21 | using namespace llvm; |
22 | using namespace llvm::jitlink; |
23 | |
24 | namespace { |
25 | |
26 | class MachOLinkGraphBuilder_x86_64 : public MachOLinkGraphBuilder { |
27 | public: |
28 | MachOLinkGraphBuilder_x86_64(const object::MachOObjectFile &Obj, |
29 | SubtargetFeatures Features) |
30 | : MachOLinkGraphBuilder(Obj, Triple("x86_64-apple-darwin" ), |
31 | std::move(Features), x86_64::getEdgeKindName) {} |
32 | |
33 | private: |
34 | enum MachONormalizedRelocationType : unsigned { |
35 | MachOBranch32, |
36 | MachOPointer32, |
37 | MachOPointer64, |
38 | MachOPointer64Anon, |
39 | MachOPCRel32, |
40 | MachOPCRel32Minus1, |
41 | MachOPCRel32Minus2, |
42 | MachOPCRel32Minus4, |
43 | MachOPCRel32Anon, |
44 | MachOPCRel32Minus1Anon, |
45 | MachOPCRel32Minus2Anon, |
46 | MachOPCRel32Minus4Anon, |
47 | MachOPCRel32GOTLoad, |
48 | MachOPCRel32GOT, |
49 | MachOPCRel32TLV, |
50 | MachOSubtractor32, |
51 | MachOSubtractor64, |
52 | }; |
53 | |
54 | static Expected<MachONormalizedRelocationType> |
55 | getRelocKind(const MachO::relocation_info &RI) { |
56 | switch (RI.r_type) { |
57 | case MachO::X86_64_RELOC_UNSIGNED: |
58 | if (!RI.r_pcrel) { |
59 | if (RI.r_length == 3) |
60 | return RI.r_extern ? MachOPointer64 : MachOPointer64Anon; |
61 | else if (RI.r_extern && RI.r_length == 2) |
62 | return MachOPointer32; |
63 | } |
64 | break; |
65 | case MachO::X86_64_RELOC_SIGNED: |
66 | if (RI.r_pcrel && RI.r_length == 2) |
67 | return RI.r_extern ? MachOPCRel32 : MachOPCRel32Anon; |
68 | break; |
69 | case MachO::X86_64_RELOC_BRANCH: |
70 | if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
71 | return MachOBranch32; |
72 | break; |
73 | case MachO::X86_64_RELOC_GOT_LOAD: |
74 | if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
75 | return MachOPCRel32GOTLoad; |
76 | break; |
77 | case MachO::X86_64_RELOC_GOT: |
78 | if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
79 | return MachOPCRel32GOT; |
80 | break; |
81 | case MachO::X86_64_RELOC_SUBTRACTOR: |
82 | if (!RI.r_pcrel && RI.r_extern) { |
83 | if (RI.r_length == 2) |
84 | return MachOSubtractor32; |
85 | else if (RI.r_length == 3) |
86 | return MachOSubtractor64; |
87 | } |
88 | break; |
89 | case MachO::X86_64_RELOC_SIGNED_1: |
90 | if (RI.r_pcrel && RI.r_length == 2) |
91 | return RI.r_extern ? MachOPCRel32Minus1 : MachOPCRel32Minus1Anon; |
92 | break; |
93 | case MachO::X86_64_RELOC_SIGNED_2: |
94 | if (RI.r_pcrel && RI.r_length == 2) |
95 | return RI.r_extern ? MachOPCRel32Minus2 : MachOPCRel32Minus2Anon; |
96 | break; |
97 | case MachO::X86_64_RELOC_SIGNED_4: |
98 | if (RI.r_pcrel && RI.r_length == 2) |
99 | return RI.r_extern ? MachOPCRel32Minus4 : MachOPCRel32Minus4Anon; |
100 | break; |
101 | case MachO::X86_64_RELOC_TLV: |
102 | if (RI.r_pcrel && RI.r_extern && RI.r_length == 2) |
103 | return MachOPCRel32TLV; |
104 | break; |
105 | } |
106 | |
107 | return make_error<JITLinkError>( |
108 | Args: "Unsupported x86-64 relocation: address=" + |
109 | formatv(Fmt: "{0:x8}" , Vals: RI.r_address) + |
110 | ", symbolnum=" + formatv(Fmt: "{0:x6}" , Vals: RI.r_symbolnum) + |
111 | ", kind=" + formatv(Fmt: "{0:x1}" , Vals: RI.r_type) + |
112 | ", pc_rel=" + (RI.r_pcrel ? "true" : "false" ) + |
113 | ", extern=" + (RI.r_extern ? "true" : "false" ) + |
114 | ", length=" + formatv(Fmt: "{0:d}" , Vals: RI.r_length)); |
115 | } |
116 | |
117 | using PairRelocInfo = std::tuple<Edge::Kind, Symbol *, uint64_t>; |
118 | |
119 | // Parses paired SUBTRACTOR/UNSIGNED relocations and, on success, |
120 | // returns the edge kind and addend to be used. |
121 | Expected<PairRelocInfo> parsePairRelocation( |
122 | Block &BlockToFix, MachONormalizedRelocationType SubtractorKind, |
123 | const MachO::relocation_info &SubRI, orc::ExecutorAddr FixupAddress, |
124 | const char *FixupContent, object::relocation_iterator &UnsignedRelItr, |
125 | object::relocation_iterator &RelEnd) { |
126 | using namespace support; |
127 | |
128 | assert(((SubtractorKind == MachOSubtractor32 && SubRI.r_length == 2) || |
129 | (SubtractorKind == MachOSubtractor64 && SubRI.r_length == 3)) && |
130 | "Subtractor kind should match length" ); |
131 | assert(SubRI.r_extern && "SUBTRACTOR reloc symbol should be extern" ); |
132 | assert(!SubRI.r_pcrel && "SUBTRACTOR reloc should not be PCRel" ); |
133 | |
134 | if (UnsignedRelItr == RelEnd) |
135 | return make_error<JITLinkError>(Args: "x86_64 SUBTRACTOR without paired " |
136 | "UNSIGNED relocation" ); |
137 | |
138 | auto UnsignedRI = getRelocationInfo(RelItr: UnsignedRelItr); |
139 | |
140 | if (SubRI.r_address != UnsignedRI.r_address) |
141 | return make_error<JITLinkError>(Args: "x86_64 SUBTRACTOR and paired UNSIGNED " |
142 | "point to different addresses" ); |
143 | |
144 | if (SubRI.r_length != UnsignedRI.r_length) |
145 | return make_error<JITLinkError>(Args: "length of x86_64 SUBTRACTOR and paired " |
146 | "UNSIGNED reloc must match" ); |
147 | |
148 | Symbol *FromSymbol; |
149 | if (auto FromSymbolOrErr = findSymbolByIndex(Index: SubRI.r_symbolnum)) |
150 | FromSymbol = FromSymbolOrErr->GraphSymbol; |
151 | else |
152 | return FromSymbolOrErr.takeError(); |
153 | |
154 | // Read the current fixup value. |
155 | uint64_t FixupValue = 0; |
156 | if (SubRI.r_length == 3) |
157 | FixupValue = *(const little64_t *)FixupContent; |
158 | else |
159 | FixupValue = *(const little32_t *)FixupContent; |
160 | |
161 | // Find 'ToSymbol' using symbol number or address, depending on whether the |
162 | // paired UNSIGNED relocation is extern. |
163 | Symbol *ToSymbol = nullptr; |
164 | if (UnsignedRI.r_extern) { |
165 | // Find target symbol by symbol index. |
166 | if (auto ToSymbolOrErr = findSymbolByIndex(Index: UnsignedRI.r_symbolnum)) |
167 | ToSymbol = ToSymbolOrErr->GraphSymbol; |
168 | else |
169 | return ToSymbolOrErr.takeError(); |
170 | } else { |
171 | auto ToSymbolSec = findSectionByIndex(Index: UnsignedRI.r_symbolnum - 1); |
172 | if (!ToSymbolSec) |
173 | return ToSymbolSec.takeError(); |
174 | ToSymbol = getSymbolByAddress(NSec&: *ToSymbolSec, Address: ToSymbolSec->Address); |
175 | assert(ToSymbol && "No symbol for section" ); |
176 | FixupValue -= ToSymbol->getAddress().getValue(); |
177 | } |
178 | |
179 | Edge::Kind DeltaKind; |
180 | Symbol *TargetSymbol; |
181 | uint64_t Addend; |
182 | |
183 | bool FixingFromSymbol = true; |
184 | if (&BlockToFix == &FromSymbol->getAddressable()) { |
185 | if (LLVM_UNLIKELY(&BlockToFix == &ToSymbol->getAddressable())) { |
186 | // From and To are symbols in the same block. Decide direction by offset |
187 | // instead. |
188 | if (ToSymbol->getAddress() > FixupAddress) |
189 | FixingFromSymbol = true; |
190 | else if (FromSymbol->getAddress() > FixupAddress) |
191 | FixingFromSymbol = false; |
192 | else |
193 | FixingFromSymbol = FromSymbol->getAddress() >= ToSymbol->getAddress(); |
194 | } else |
195 | FixingFromSymbol = true; |
196 | } else { |
197 | if (&BlockToFix == &ToSymbol->getAddressable()) |
198 | FixingFromSymbol = false; |
199 | else { |
200 | // BlockToFix was neither FromSymbol nor ToSymbol. |
201 | return make_error<JITLinkError>(Args: "SUBTRACTOR relocation must fix up " |
202 | "either 'A' or 'B' (or a symbol in one " |
203 | "of their alt-entry groups)" ); |
204 | } |
205 | } |
206 | |
207 | if (FixingFromSymbol) { |
208 | TargetSymbol = ToSymbol; |
209 | DeltaKind = (SubRI.r_length == 3) ? x86_64::Delta64 : x86_64::Delta32; |
210 | Addend = FixupValue + (FixupAddress - FromSymbol->getAddress()); |
211 | // FIXME: handle extern 'from'. |
212 | } else { |
213 | TargetSymbol = FromSymbol; |
214 | DeltaKind = |
215 | (SubRI.r_length == 3) ? x86_64::NegDelta64 : x86_64::NegDelta32; |
216 | Addend = FixupValue - (FixupAddress - ToSymbol->getAddress()); |
217 | } |
218 | |
219 | return PairRelocInfo(DeltaKind, TargetSymbol, Addend); |
220 | } |
221 | |
222 | Error addRelocations() override { |
223 | using namespace support; |
224 | auto &Obj = getObject(); |
225 | |
226 | LLVM_DEBUG(dbgs() << "Processing relocations:\n" ); |
227 | |
228 | for (const auto &S : Obj.sections()) { |
229 | |
230 | orc::ExecutorAddr SectionAddress(S.getAddress()); |
231 | |
232 | // Skip relocations virtual sections. |
233 | if (S.isVirtual()) { |
234 | if (S.relocation_begin() != S.relocation_end()) |
235 | return make_error<JITLinkError>(Args: "Virtual section contains " |
236 | "relocations" ); |
237 | continue; |
238 | } |
239 | |
240 | auto NSec = |
241 | findSectionByIndex(Index: Obj.getSectionIndex(Sec: S.getRawDataRefImpl())); |
242 | if (!NSec) |
243 | return NSec.takeError(); |
244 | |
245 | // Skip relocations for MachO sections without corresponding graph |
246 | // sections. |
247 | { |
248 | if (!NSec->GraphSection) { |
249 | LLVM_DEBUG({ |
250 | dbgs() << " Skipping relocations for MachO section " |
251 | << NSec->SegName << "/" << NSec->SectName |
252 | << " which has no associated graph section\n" ; |
253 | }); |
254 | continue; |
255 | } |
256 | } |
257 | |
258 | // Add relocations for section. |
259 | for (auto RelItr = S.relocation_begin(), RelEnd = S.relocation_end(); |
260 | RelItr != RelEnd; ++RelItr) { |
261 | |
262 | MachO::relocation_info RI = getRelocationInfo(RelItr); |
263 | |
264 | // Find the address of the value to fix up. |
265 | auto FixupAddress = SectionAddress + (uint32_t)RI.r_address; |
266 | |
267 | LLVM_DEBUG({ |
268 | dbgs() << " " << NSec->SectName << " + " |
269 | << formatv("{0:x8}" , RI.r_address) << ":\n" ; |
270 | }); |
271 | |
272 | // Find the block that the fixup points to. |
273 | Block *BlockToFix = nullptr; |
274 | { |
275 | auto SymbolToFixOrErr = findSymbolByAddress(NSec&: *NSec, Address: FixupAddress); |
276 | if (!SymbolToFixOrErr) |
277 | return SymbolToFixOrErr.takeError(); |
278 | BlockToFix = &SymbolToFixOrErr->getBlock(); |
279 | } |
280 | |
281 | if (FixupAddress + orc::ExecutorAddrDiff(1ULL << RI.r_length) > |
282 | BlockToFix->getAddress() + BlockToFix->getContent().size()) |
283 | return make_error<JITLinkError>( |
284 | Args: "Relocation extends past end of fixup block" ); |
285 | |
286 | // Get a pointer to the fixup content. |
287 | const char *FixupContent = BlockToFix->getContent().data() + |
288 | (FixupAddress - BlockToFix->getAddress()); |
289 | |
290 | size_t FixupOffset = FixupAddress - BlockToFix->getAddress(); |
291 | |
292 | // The target symbol and addend will be populated by the switch below. |
293 | Symbol *TargetSymbol = nullptr; |
294 | uint64_t Addend = 0; |
295 | |
296 | // Validate the relocation kind. |
297 | auto MachORelocKind = getRelocKind(RI); |
298 | if (!MachORelocKind) |
299 | return MachORelocKind.takeError(); |
300 | |
301 | Edge::Kind Kind = Edge::Invalid; |
302 | |
303 | switch (*MachORelocKind) { |
304 | case MachOBranch32: |
305 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
306 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
307 | else |
308 | return TargetSymbolOrErr.takeError(); |
309 | Addend = *(const little32_t *)FixupContent; |
310 | Kind = x86_64::BranchPCRel32; |
311 | break; |
312 | case MachOPCRel32: |
313 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
314 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
315 | else |
316 | return TargetSymbolOrErr.takeError(); |
317 | Addend = *(const little32_t *)FixupContent - 4; |
318 | Kind = x86_64::Delta32; |
319 | break; |
320 | case MachOPCRel32GOTLoad: |
321 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
322 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
323 | else |
324 | return TargetSymbolOrErr.takeError(); |
325 | Addend = *(const little32_t *)FixupContent; |
326 | Kind = x86_64::RequestGOTAndTransformToPCRel32GOTLoadREXRelaxable; |
327 | if (FixupOffset < 3) |
328 | return make_error<JITLinkError>(Args: "GOTLD at invalid offset " + |
329 | formatv(Fmt: "{0}" , Vals&: FixupOffset)); |
330 | break; |
331 | case MachOPCRel32GOT: |
332 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
333 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
334 | else |
335 | return TargetSymbolOrErr.takeError(); |
336 | Addend = *(const little32_t *)FixupContent - 4; |
337 | Kind = x86_64::RequestGOTAndTransformToDelta32; |
338 | break; |
339 | case MachOPCRel32TLV: |
340 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
341 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
342 | else |
343 | return TargetSymbolOrErr.takeError(); |
344 | Addend = *(const little32_t *)FixupContent; |
345 | Kind = x86_64::RequestTLVPAndTransformToPCRel32TLVPLoadREXRelaxable; |
346 | if (FixupOffset < 3) |
347 | return make_error<JITLinkError>(Args: "TLV at invalid offset " + |
348 | formatv(Fmt: "{0}" , Vals&: FixupOffset)); |
349 | break; |
350 | case MachOPointer32: |
351 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
352 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
353 | else |
354 | return TargetSymbolOrErr.takeError(); |
355 | Addend = *(const ulittle32_t *)FixupContent; |
356 | Kind = x86_64::Pointer32; |
357 | break; |
358 | case MachOPointer64: |
359 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
360 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
361 | else |
362 | return TargetSymbolOrErr.takeError(); |
363 | Addend = *(const ulittle64_t *)FixupContent; |
364 | Kind = x86_64::Pointer64; |
365 | break; |
366 | case MachOPointer64Anon: { |
367 | orc::ExecutorAddr TargetAddress(*(const ulittle64_t *)FixupContent); |
368 | auto TargetNSec = findSectionByIndex(Index: RI.r_symbolnum - 1); |
369 | if (!TargetNSec) |
370 | return TargetNSec.takeError(); |
371 | if (auto TargetSymbolOrErr = |
372 | findSymbolByAddress(NSec&: *TargetNSec, Address: TargetAddress)) |
373 | TargetSymbol = &*TargetSymbolOrErr; |
374 | else |
375 | return TargetSymbolOrErr.takeError(); |
376 | Addend = TargetAddress - TargetSymbol->getAddress(); |
377 | Kind = x86_64::Pointer64; |
378 | break; |
379 | } |
380 | case MachOPCRel32Minus1: |
381 | case MachOPCRel32Minus2: |
382 | case MachOPCRel32Minus4: |
383 | if (auto TargetSymbolOrErr = findSymbolByIndex(Index: RI.r_symbolnum)) |
384 | TargetSymbol = TargetSymbolOrErr->GraphSymbol; |
385 | else |
386 | return TargetSymbolOrErr.takeError(); |
387 | Addend = *(const little32_t *)FixupContent - 4; |
388 | Kind = x86_64::Delta32; |
389 | break; |
390 | case MachOPCRel32Anon: { |
391 | orc::ExecutorAddr TargetAddress(FixupAddress + 4 + |
392 | *(const little32_t *)FixupContent); |
393 | auto TargetNSec = findSectionByIndex(Index: RI.r_symbolnum - 1); |
394 | if (!TargetNSec) |
395 | return TargetNSec.takeError(); |
396 | if (auto TargetSymbolOrErr = |
397 | findSymbolByAddress(NSec&: *TargetNSec, Address: TargetAddress)) |
398 | TargetSymbol = &*TargetSymbolOrErr; |
399 | else |
400 | return TargetSymbolOrErr.takeError(); |
401 | Addend = TargetAddress - TargetSymbol->getAddress() - 4; |
402 | Kind = x86_64::Delta32; |
403 | break; |
404 | } |
405 | case MachOPCRel32Minus1Anon: |
406 | case MachOPCRel32Minus2Anon: |
407 | case MachOPCRel32Minus4Anon: { |
408 | orc::ExecutorAddrDiff Delta = |
409 | 4 + orc::ExecutorAddrDiff( |
410 | 1ULL << (*MachORelocKind - MachOPCRel32Minus1Anon)); |
411 | orc::ExecutorAddr TargetAddress = |
412 | FixupAddress + Delta + *(const little32_t *)FixupContent; |
413 | auto TargetNSec = findSectionByIndex(Index: RI.r_symbolnum - 1); |
414 | if (!TargetNSec) |
415 | return TargetNSec.takeError(); |
416 | if (auto TargetSymbolOrErr = |
417 | findSymbolByAddress(NSec&: *TargetNSec, Address: TargetAddress)) |
418 | TargetSymbol = &*TargetSymbolOrErr; |
419 | else |
420 | return TargetSymbolOrErr.takeError(); |
421 | Addend = TargetAddress - TargetSymbol->getAddress() - Delta; |
422 | Kind = x86_64::Delta32; |
423 | break; |
424 | } |
425 | case MachOSubtractor32: |
426 | case MachOSubtractor64: { |
427 | // We use Delta32/Delta64 to represent SUBTRACTOR relocations. |
428 | // parsePairRelocation handles the paired reloc, and returns the |
429 | // edge kind to be used (either Delta32/Delta64, or |
430 | // NegDelta32/NegDelta64, depending on the direction of the |
431 | // subtraction) along with the addend. |
432 | auto PairInfo = |
433 | parsePairRelocation(BlockToFix&: *BlockToFix, SubtractorKind: *MachORelocKind, SubRI: RI, |
434 | FixupAddress, FixupContent, UnsignedRelItr&: ++RelItr, RelEnd); |
435 | if (!PairInfo) |
436 | return PairInfo.takeError(); |
437 | std::tie(args&: Kind, args&: TargetSymbol, args&: Addend) = *PairInfo; |
438 | assert(TargetSymbol && "No target symbol from parsePairRelocation?" ); |
439 | break; |
440 | } |
441 | } |
442 | |
443 | LLVM_DEBUG({ |
444 | dbgs() << " " ; |
445 | Edge GE(Kind, FixupAddress - BlockToFix->getAddress(), *TargetSymbol, |
446 | Addend); |
447 | printEdge(dbgs(), *BlockToFix, GE, x86_64::getEdgeKindName(Kind)); |
448 | dbgs() << "\n" ; |
449 | }); |
450 | BlockToFix->addEdge(K: Kind, Offset: FixupAddress - BlockToFix->getAddress(), |
451 | Target&: *TargetSymbol, Addend); |
452 | } |
453 | } |
454 | return Error::success(); |
455 | } |
456 | }; |
457 | |
458 | Error buildGOTAndStubs_MachO_x86_64(LinkGraph &G) { |
459 | x86_64::GOTTableManager GOT; |
460 | x86_64::PLTTableManager PLT(GOT); |
461 | visitExistingEdges(G, Vs&: GOT, Vs&: PLT); |
462 | return Error::success(); |
463 | } |
464 | |
465 | } // namespace |
466 | |
467 | namespace llvm { |
468 | namespace jitlink { |
469 | |
470 | class MachOJITLinker_x86_64 : public JITLinker<MachOJITLinker_x86_64> { |
471 | friend class JITLinker<MachOJITLinker_x86_64>; |
472 | |
473 | public: |
474 | MachOJITLinker_x86_64(std::unique_ptr<JITLinkContext> Ctx, |
475 | std::unique_ptr<LinkGraph> G, |
476 | PassConfiguration PassConfig) |
477 | : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} |
478 | |
479 | private: |
480 | Error applyFixup(LinkGraph &G, Block &B, const Edge &E) const { |
481 | return x86_64::applyFixup(G, B, E, GOTSymbol: nullptr); |
482 | } |
483 | }; |
484 | |
485 | Expected<std::unique_ptr<LinkGraph>> |
486 | createLinkGraphFromMachOObject_x86_64(MemoryBufferRef ObjectBuffer) { |
487 | auto MachOObj = object::ObjectFile::createMachOObjectFile(Object: ObjectBuffer); |
488 | if (!MachOObj) |
489 | return MachOObj.takeError(); |
490 | |
491 | auto Features = (*MachOObj)->getFeatures(); |
492 | if (!Features) |
493 | return Features.takeError(); |
494 | |
495 | return MachOLinkGraphBuilder_x86_64(**MachOObj, std::move(*Features)) |
496 | .buildGraph(); |
497 | } |
498 | |
499 | void link_MachO_x86_64(std::unique_ptr<LinkGraph> G, |
500 | std::unique_ptr<JITLinkContext> Ctx) { |
501 | |
502 | PassConfiguration Config; |
503 | |
504 | if (Ctx->shouldAddDefaultTargetPasses(TT: G->getTargetTriple())) { |
505 | // Add eh-frame passes. |
506 | Config.PrePrunePasses.push_back(x: createEHFrameSplitterPass_MachO_x86_64()); |
507 | Config.PrePrunePasses.push_back(x: createEHFrameEdgeFixerPass_MachO_x86_64()); |
508 | |
509 | // Add compact unwind splitter pass. |
510 | Config.PrePrunePasses.push_back( |
511 | x: CompactUnwindSplitter("__LD,__compact_unwind" )); |
512 | |
513 | // Add a mark-live pass. |
514 | if (auto MarkLive = Ctx->getMarkLivePass(TT: G->getTargetTriple())) |
515 | Config.PrePrunePasses.push_back(x: std::move(MarkLive)); |
516 | else |
517 | Config.PrePrunePasses.push_back(x: markAllSymbolsLive); |
518 | |
519 | // Add an in-place GOT/Stubs pass. |
520 | Config.PostPrunePasses.push_back(x: buildGOTAndStubs_MachO_x86_64); |
521 | |
522 | // Add GOT/Stubs optimizer pass. |
523 | Config.PreFixupPasses.push_back(x: x86_64::optimizeGOTAndStubAccesses); |
524 | } |
525 | |
526 | if (auto Err = Ctx->modifyPassConfig(G&: *G, Config)) |
527 | return Ctx->notifyFailed(Err: std::move(Err)); |
528 | |
529 | // Construct a JITLinker and run the link function. |
530 | MachOJITLinker_x86_64::link(Args: std::move(Ctx), Args: std::move(G), Args: std::move(Config)); |
531 | } |
532 | |
533 | LinkGraphPassFunction createEHFrameSplitterPass_MachO_x86_64() { |
534 | return DWARFRecordSectionSplitter("__TEXT,__eh_frame" ); |
535 | } |
536 | |
537 | LinkGraphPassFunction createEHFrameEdgeFixerPass_MachO_x86_64() { |
538 | return EHFrameEdgeFixer("__TEXT,__eh_frame" , x86_64::PointerSize, |
539 | x86_64::Pointer32, x86_64::Pointer64, x86_64::Delta32, |
540 | x86_64::Delta64, x86_64::NegDelta32); |
541 | } |
542 | |
543 | } // end namespace jitlink |
544 | } // end namespace llvm |
545 | |