1 //===---- IndirectionUtils.cpp - Utilities for call indirection in Orc ----===// 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 #include "llvm/ExecutionEngine/Orc/IndirectionUtils.h" 10 #include "llvm/ADT/STLExtras.h" 11 #include "llvm/ADT/Triple.h" 12 #include "llvm/ExecutionEngine/JITLink/x86_64.h" 13 #include "llvm/ExecutionEngine/Orc/OrcABISupport.h" 14 #include "llvm/IR/IRBuilder.h" 15 #include "llvm/MC/MCDisassembler/MCDisassembler.h" 16 #include "llvm/MC/MCInstrAnalysis.h" 17 #include "llvm/Support/Format.h" 18 #include "llvm/Transforms/Utils/Cloning.h" 19 #include <sstream> 20 21 #define DEBUG_TYPE "orc" 22 23 using namespace llvm; 24 using namespace llvm::orc; 25 26 namespace { 27 28 class CompileCallbackMaterializationUnit : public orc::MaterializationUnit { 29 public: 30 using CompileFunction = JITCompileCallbackManager::CompileFunction; 31 32 CompileCallbackMaterializationUnit(SymbolStringPtr Name, 33 CompileFunction Compile) 34 : MaterializationUnit(Interface( 35 SymbolFlagsMap({{Name, JITSymbolFlags::Exported}}), nullptr)), 36 Name(std::move(Name)), Compile(std::move(Compile)) {} 37 38 StringRef getName() const override { return "<Compile Callbacks>"; } 39 40 private: 41 void materialize(std::unique_ptr<MaterializationResponsibility> R) override { 42 SymbolMap Result; 43 Result[Name] = JITEvaluatedSymbol(Compile(), JITSymbolFlags::Exported); 44 // No dependencies, so these calls cannot fail. 45 cantFail(R->notifyResolved(Result)); 46 cantFail(R->notifyEmitted()); 47 } 48 49 void discard(const JITDylib &JD, const SymbolStringPtr &Name) override { 50 llvm_unreachable("Discard should never occur on a LMU?"); 51 } 52 53 SymbolStringPtr Name; 54 CompileFunction Compile; 55 }; 56 57 } // namespace 58 59 namespace llvm { 60 namespace orc { 61 62 TrampolinePool::~TrampolinePool() {} 63 void IndirectStubsManager::anchor() {} 64 65 Expected<JITTargetAddress> 66 JITCompileCallbackManager::getCompileCallback(CompileFunction Compile) { 67 if (auto TrampolineAddr = TP->getTrampoline()) { 68 auto CallbackName = 69 ES.intern(std::string("cc") + std::to_string(++NextCallbackId)); 70 71 std::lock_guard<std::mutex> Lock(CCMgrMutex); 72 AddrToSymbol[*TrampolineAddr] = CallbackName; 73 cantFail( 74 CallbacksJD.define(std::make_unique<CompileCallbackMaterializationUnit>( 75 std::move(CallbackName), std::move(Compile)))); 76 return *TrampolineAddr; 77 } else 78 return TrampolineAddr.takeError(); 79 } 80 81 JITTargetAddress JITCompileCallbackManager::executeCompileCallback( 82 JITTargetAddress TrampolineAddr) { 83 SymbolStringPtr Name; 84 85 { 86 std::unique_lock<std::mutex> Lock(CCMgrMutex); 87 auto I = AddrToSymbol.find(TrampolineAddr); 88 89 // If this address is not associated with a compile callback then report an 90 // error to the execution session and return ErrorHandlerAddress to the 91 // callee. 92 if (I == AddrToSymbol.end()) { 93 Lock.unlock(); 94 std::string ErrMsg; 95 { 96 raw_string_ostream ErrMsgStream(ErrMsg); 97 ErrMsgStream << "No compile callback for trampoline at " 98 << format("0x%016" PRIx64, TrampolineAddr); 99 } 100 ES.reportError( 101 make_error<StringError>(std::move(ErrMsg), inconvertibleErrorCode())); 102 return ErrorHandlerAddress; 103 } else 104 Name = I->second; 105 } 106 107 if (auto Sym = 108 ES.lookup(makeJITDylibSearchOrder( 109 &CallbacksJD, JITDylibLookupFlags::MatchAllSymbols), 110 Name)) 111 return Sym->getAddress(); 112 else { 113 llvm::dbgs() << "Didn't find callback.\n"; 114 // If anything goes wrong materializing Sym then report it to the session 115 // and return the ErrorHandlerAddress; 116 ES.reportError(Sym.takeError()); 117 return ErrorHandlerAddress; 118 } 119 } 120 121 Expected<std::unique_ptr<JITCompileCallbackManager>> 122 createLocalCompileCallbackManager(const Triple &T, ExecutionSession &ES, 123 JITTargetAddress ErrorHandlerAddress) { 124 switch (T.getArch()) { 125 default: 126 return make_error<StringError>( 127 std::string("No callback manager available for ") + T.str(), 128 inconvertibleErrorCode()); 129 case Triple::aarch64: 130 case Triple::aarch64_32: { 131 typedef orc::LocalJITCompileCallbackManager<orc::OrcAArch64> CCMgrT; 132 return CCMgrT::Create(ES, ErrorHandlerAddress); 133 } 134 135 case Triple::x86: { 136 typedef orc::LocalJITCompileCallbackManager<orc::OrcI386> CCMgrT; 137 return CCMgrT::Create(ES, ErrorHandlerAddress); 138 } 139 140 case Triple::mips: { 141 typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Be> CCMgrT; 142 return CCMgrT::Create(ES, ErrorHandlerAddress); 143 } 144 case Triple::mipsel: { 145 typedef orc::LocalJITCompileCallbackManager<orc::OrcMips32Le> CCMgrT; 146 return CCMgrT::Create(ES, ErrorHandlerAddress); 147 } 148 149 case Triple::mips64: 150 case Triple::mips64el: { 151 typedef orc::LocalJITCompileCallbackManager<orc::OrcMips64> CCMgrT; 152 return CCMgrT::Create(ES, ErrorHandlerAddress); 153 } 154 155 case Triple::x86_64: { 156 if (T.getOS() == Triple::OSType::Win32) { 157 typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT; 158 return CCMgrT::Create(ES, ErrorHandlerAddress); 159 } else { 160 typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT; 161 return CCMgrT::Create(ES, ErrorHandlerAddress); 162 } 163 } 164 165 } 166 } 167 168 std::function<std::unique_ptr<IndirectStubsManager>()> 169 createLocalIndirectStubsManagerBuilder(const Triple &T) { 170 switch (T.getArch()) { 171 default: 172 return [](){ 173 return std::make_unique< 174 orc::LocalIndirectStubsManager<orc::OrcGenericABI>>(); 175 }; 176 177 case Triple::aarch64: 178 case Triple::aarch64_32: 179 return [](){ 180 return std::make_unique< 181 orc::LocalIndirectStubsManager<orc::OrcAArch64>>(); 182 }; 183 184 case Triple::x86: 185 return [](){ 186 return std::make_unique< 187 orc::LocalIndirectStubsManager<orc::OrcI386>>(); 188 }; 189 190 case Triple::mips: 191 return [](){ 192 return std::make_unique< 193 orc::LocalIndirectStubsManager<orc::OrcMips32Be>>(); 194 }; 195 196 case Triple::mipsel: 197 return [](){ 198 return std::make_unique< 199 orc::LocalIndirectStubsManager<orc::OrcMips32Le>>(); 200 }; 201 202 case Triple::mips64: 203 case Triple::mips64el: 204 return [](){ 205 return std::make_unique< 206 orc::LocalIndirectStubsManager<orc::OrcMips64>>(); 207 }; 208 209 case Triple::x86_64: 210 if (T.getOS() == Triple::OSType::Win32) { 211 return [](){ 212 return std::make_unique< 213 orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>(); 214 }; 215 } else { 216 return [](){ 217 return std::make_unique< 218 orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>(); 219 }; 220 } 221 222 } 223 } 224 225 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) { 226 Constant *AddrIntVal = 227 ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr); 228 Constant *AddrPtrVal = 229 ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal, 230 PointerType::get(&FT, 0)); 231 return AddrPtrVal; 232 } 233 234 GlobalVariable* createImplPointer(PointerType &PT, Module &M, 235 const Twine &Name, Constant *Initializer) { 236 auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage, 237 Initializer, Name, nullptr, 238 GlobalValue::NotThreadLocal, 0, true); 239 IP->setVisibility(GlobalValue::HiddenVisibility); 240 return IP; 241 } 242 243 void makeStub(Function &F, Value &ImplPointer) { 244 assert(F.isDeclaration() && "Can't turn a definition into a stub."); 245 assert(F.getParent() && "Function isn't in a module."); 246 Module &M = *F.getParent(); 247 BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F); 248 IRBuilder<> Builder(EntryBlock); 249 LoadInst *ImplAddr = Builder.CreateLoad(F.getType(), &ImplPointer); 250 std::vector<Value*> CallArgs; 251 for (auto &A : F.args()) 252 CallArgs.push_back(&A); 253 CallInst *Call = Builder.CreateCall(F.getFunctionType(), ImplAddr, CallArgs); 254 Call->setTailCall(); 255 Call->setAttributes(F.getAttributes()); 256 if (F.getReturnType()->isVoidTy()) 257 Builder.CreateRetVoid(); 258 else 259 Builder.CreateRet(Call); 260 } 261 262 std::vector<GlobalValue *> SymbolLinkagePromoter::operator()(Module &M) { 263 std::vector<GlobalValue *> PromotedGlobals; 264 265 for (auto &GV : M.global_values()) { 266 bool Promoted = true; 267 268 // Rename if necessary. 269 if (!GV.hasName()) 270 GV.setName("__orc_anon." + Twine(NextId++)); 271 else if (GV.getName().startswith("\01L")) 272 GV.setName("__" + GV.getName().substr(1) + "." + Twine(NextId++)); 273 else if (GV.hasLocalLinkage()) 274 GV.setName("__orc_lcl." + GV.getName() + "." + Twine(NextId++)); 275 else 276 Promoted = false; 277 278 if (GV.hasLocalLinkage()) { 279 GV.setLinkage(GlobalValue::ExternalLinkage); 280 GV.setVisibility(GlobalValue::HiddenVisibility); 281 Promoted = true; 282 } 283 GV.setUnnamedAddr(GlobalValue::UnnamedAddr::None); 284 285 if (Promoted) 286 PromotedGlobals.push_back(&GV); 287 } 288 289 return PromotedGlobals; 290 } 291 292 Function* cloneFunctionDecl(Module &Dst, const Function &F, 293 ValueToValueMapTy *VMap) { 294 Function *NewF = 295 Function::Create(cast<FunctionType>(F.getValueType()), 296 F.getLinkage(), F.getName(), &Dst); 297 NewF->copyAttributesFrom(&F); 298 299 if (VMap) { 300 (*VMap)[&F] = NewF; 301 auto NewArgI = NewF->arg_begin(); 302 for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE; 303 ++ArgI, ++NewArgI) 304 (*VMap)[&*ArgI] = &*NewArgI; 305 } 306 307 return NewF; 308 } 309 310 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap, 311 ValueMaterializer *Materializer, 312 Function *NewF) { 313 assert(!OrigF.isDeclaration() && "Nothing to move"); 314 if (!NewF) 315 NewF = cast<Function>(VMap[&OrigF]); 316 else 317 assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap."); 318 assert(NewF && "Function mapping missing from VMap."); 319 assert(NewF->getParent() != OrigF.getParent() && 320 "moveFunctionBody should only be used to move bodies between " 321 "modules."); 322 323 SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned. 324 CloneFunctionInto(NewF, &OrigF, VMap, 325 CloneFunctionChangeType::DifferentModule, Returns, "", 326 nullptr, nullptr, Materializer); 327 OrigF.deleteBody(); 328 } 329 330 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV, 331 ValueToValueMapTy *VMap) { 332 GlobalVariable *NewGV = new GlobalVariable( 333 Dst, GV.getValueType(), GV.isConstant(), 334 GV.getLinkage(), nullptr, GV.getName(), nullptr, 335 GV.getThreadLocalMode(), GV.getType()->getAddressSpace()); 336 NewGV->copyAttributesFrom(&GV); 337 if (VMap) 338 (*VMap)[&GV] = NewGV; 339 return NewGV; 340 } 341 342 void moveGlobalVariableInitializer(GlobalVariable &OrigGV, 343 ValueToValueMapTy &VMap, 344 ValueMaterializer *Materializer, 345 GlobalVariable *NewGV) { 346 assert(OrigGV.hasInitializer() && "Nothing to move"); 347 if (!NewGV) 348 NewGV = cast<GlobalVariable>(VMap[&OrigGV]); 349 else 350 assert(VMap[&OrigGV] == NewGV && 351 "Incorrect global variable mapping in VMap."); 352 assert(NewGV->getParent() != OrigGV.getParent() && 353 "moveGlobalVariableInitializer should only be used to move " 354 "initializers between modules"); 355 356 NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None, 357 nullptr, Materializer)); 358 } 359 360 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA, 361 ValueToValueMapTy &VMap) { 362 assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?"); 363 auto *NewA = GlobalAlias::create(OrigA.getValueType(), 364 OrigA.getType()->getPointerAddressSpace(), 365 OrigA.getLinkage(), OrigA.getName(), &Dst); 366 NewA->copyAttributesFrom(&OrigA); 367 VMap[&OrigA] = NewA; 368 return NewA; 369 } 370 371 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src, 372 ValueToValueMapTy &VMap) { 373 auto *MFs = Src.getModuleFlagsMetadata(); 374 if (!MFs) 375 return; 376 for (auto *MF : MFs->operands()) 377 Dst.addModuleFlag(MapMetadata(MF, VMap)); 378 } 379 380 Error addFunctionPointerRelocationsToCurrentSymbol(jitlink::Symbol &Sym, 381 jitlink::LinkGraph &G, 382 MCDisassembler &Disassembler, 383 MCInstrAnalysis &MIA) { 384 // AArch64 appears to already come with the necessary relocations. Among other 385 // architectures, only x86_64 is currently implemented here. 386 if (G.getTargetTriple().getArch() != Triple::x86_64) 387 return Error::success(); 388 389 raw_null_ostream CommentStream; 390 auto &STI = Disassembler.getSubtargetInfo(); 391 392 // Determine the function bounds 393 auto &B = Sym.getBlock(); 394 assert(!B.isZeroFill() && "expected content block"); 395 auto SymAddress = Sym.getAddress(); 396 auto SymStartInBlock = 397 (const uint8_t *)B.getContent().data() + Sym.getOffset(); 398 auto SymSize = Sym.getSize() ? Sym.getSize() : B.getSize() - Sym.getOffset(); 399 auto Content = makeArrayRef(SymStartInBlock, SymSize); 400 401 LLVM_DEBUG(dbgs() << "Adding self-relocations to " << Sym.getName() << "\n"); 402 403 SmallDenseSet<uintptr_t, 8> ExistingRelocations; 404 for (auto &E : B.edges()) { 405 if (E.isRelocation()) 406 ExistingRelocations.insert(E.getOffset()); 407 } 408 409 size_t I = 0; 410 while (I < Content.size()) { 411 MCInst Instr; 412 uint64_t InstrSize = 0; 413 uint64_t InstrStart = SymAddress.getValue() + I; 414 auto DecodeStatus = Disassembler.getInstruction( 415 Instr, InstrSize, Content.drop_front(I), InstrStart, CommentStream); 416 if (DecodeStatus != MCDisassembler::Success) { 417 LLVM_DEBUG(dbgs() << "Aborting due to disassembly failure at address " 418 << InstrStart); 419 return make_error<StringError>( 420 formatv("failed to disassemble at address {0:x16}", InstrStart), 421 inconvertibleErrorCode()); 422 } 423 // Advance to the next instruction. 424 I += InstrSize; 425 426 // Check for a PC-relative address equal to the symbol itself. 427 auto PCRelAddr = 428 MIA.evaluateMemoryOperandAddress(Instr, &STI, InstrStart, InstrSize); 429 if (!PCRelAddr || *PCRelAddr != SymAddress.getValue()) 430 continue; 431 432 auto RelocOffInInstr = 433 MIA.getMemoryOperandRelocationOffset(Instr, InstrSize); 434 if (!RelocOffInInstr.hasValue() || 435 InstrSize - RelocOffInInstr.getValue() != 4) { 436 LLVM_DEBUG(dbgs() << "Skipping unknown self-relocation at " 437 << InstrStart); 438 continue; 439 } 440 441 auto RelocOffInBlock = orc::ExecutorAddr(InstrStart) + *RelocOffInInstr - 442 SymAddress + Sym.getOffset(); 443 if (ExistingRelocations.contains(RelocOffInBlock)) 444 continue; 445 446 LLVM_DEBUG(dbgs() << "Adding delta32 self-relocation at " << InstrStart); 447 B.addEdge(jitlink::x86_64::Delta32, RelocOffInBlock, Sym, /*Addend=*/-4); 448 } 449 return Error::success(); 450 } 451 452 } // End namespace orc. 453 } // End namespace llvm. 454