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() = default; 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::riscv64: { 156 typedef orc::LocalJITCompileCallbackManager<orc::OrcRiscv64> CCMgrT; 157 return CCMgrT::Create(ES, ErrorHandlerAddress); 158 } 159 160 case Triple::x86_64: { 161 if (T.getOS() == Triple::OSType::Win32) { 162 typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_Win32> CCMgrT; 163 return CCMgrT::Create(ES, ErrorHandlerAddress); 164 } else { 165 typedef orc::LocalJITCompileCallbackManager<orc::OrcX86_64_SysV> CCMgrT; 166 return CCMgrT::Create(ES, ErrorHandlerAddress); 167 } 168 } 169 170 } 171 } 172 173 std::function<std::unique_ptr<IndirectStubsManager>()> 174 createLocalIndirectStubsManagerBuilder(const Triple &T) { 175 switch (T.getArch()) { 176 default: 177 return [](){ 178 return std::make_unique< 179 orc::LocalIndirectStubsManager<orc::OrcGenericABI>>(); 180 }; 181 182 case Triple::aarch64: 183 case Triple::aarch64_32: 184 return [](){ 185 return std::make_unique< 186 orc::LocalIndirectStubsManager<orc::OrcAArch64>>(); 187 }; 188 189 case Triple::x86: 190 return [](){ 191 return std::make_unique< 192 orc::LocalIndirectStubsManager<orc::OrcI386>>(); 193 }; 194 195 case Triple::mips: 196 return [](){ 197 return std::make_unique< 198 orc::LocalIndirectStubsManager<orc::OrcMips32Be>>(); 199 }; 200 201 case Triple::mipsel: 202 return [](){ 203 return std::make_unique< 204 orc::LocalIndirectStubsManager<orc::OrcMips32Le>>(); 205 }; 206 207 case Triple::mips64: 208 case Triple::mips64el: 209 return [](){ 210 return std::make_unique< 211 orc::LocalIndirectStubsManager<orc::OrcMips64>>(); 212 }; 213 214 case Triple::riscv64: 215 return []() { 216 return std::make_unique< 217 orc::LocalIndirectStubsManager<orc::OrcRiscv64>>(); 218 }; 219 220 case Triple::x86_64: 221 if (T.getOS() == Triple::OSType::Win32) { 222 return [](){ 223 return std::make_unique< 224 orc::LocalIndirectStubsManager<orc::OrcX86_64_Win32>>(); 225 }; 226 } else { 227 return [](){ 228 return std::make_unique< 229 orc::LocalIndirectStubsManager<orc::OrcX86_64_SysV>>(); 230 }; 231 } 232 233 } 234 } 235 236 Constant* createIRTypedAddress(FunctionType &FT, JITTargetAddress Addr) { 237 Constant *AddrIntVal = 238 ConstantInt::get(Type::getInt64Ty(FT.getContext()), Addr); 239 Constant *AddrPtrVal = 240 ConstantExpr::getCast(Instruction::IntToPtr, AddrIntVal, 241 PointerType::get(&FT, 0)); 242 return AddrPtrVal; 243 } 244 245 GlobalVariable* createImplPointer(PointerType &PT, Module &M, 246 const Twine &Name, Constant *Initializer) { 247 auto IP = new GlobalVariable(M, &PT, false, GlobalValue::ExternalLinkage, 248 Initializer, Name, nullptr, 249 GlobalValue::NotThreadLocal, 0, true); 250 IP->setVisibility(GlobalValue::HiddenVisibility); 251 return IP; 252 } 253 254 void makeStub(Function &F, Value &ImplPointer) { 255 assert(F.isDeclaration() && "Can't turn a definition into a stub."); 256 assert(F.getParent() && "Function isn't in a module."); 257 Module &M = *F.getParent(); 258 BasicBlock *EntryBlock = BasicBlock::Create(M.getContext(), "entry", &F); 259 IRBuilder<> Builder(EntryBlock); 260 LoadInst *ImplAddr = Builder.CreateLoad(F.getType(), &ImplPointer); 261 std::vector<Value*> CallArgs; 262 for (auto &A : F.args()) 263 CallArgs.push_back(&A); 264 CallInst *Call = Builder.CreateCall(F.getFunctionType(), ImplAddr, CallArgs); 265 Call->setTailCall(); 266 Call->setAttributes(F.getAttributes()); 267 if (F.getReturnType()->isVoidTy()) 268 Builder.CreateRetVoid(); 269 else 270 Builder.CreateRet(Call); 271 } 272 273 std::vector<GlobalValue *> SymbolLinkagePromoter::operator()(Module &M) { 274 std::vector<GlobalValue *> PromotedGlobals; 275 276 for (auto &GV : M.global_values()) { 277 bool Promoted = true; 278 279 // Rename if necessary. 280 if (!GV.hasName()) 281 GV.setName("__orc_anon." + Twine(NextId++)); 282 else if (GV.getName().startswith("\01L")) 283 GV.setName("__" + GV.getName().substr(1) + "." + Twine(NextId++)); 284 else if (GV.hasLocalLinkage()) 285 GV.setName("__orc_lcl." + GV.getName() + "." + Twine(NextId++)); 286 else 287 Promoted = false; 288 289 if (GV.hasLocalLinkage()) { 290 GV.setLinkage(GlobalValue::ExternalLinkage); 291 GV.setVisibility(GlobalValue::HiddenVisibility); 292 Promoted = true; 293 } 294 GV.setUnnamedAddr(GlobalValue::UnnamedAddr::None); 295 296 if (Promoted) 297 PromotedGlobals.push_back(&GV); 298 } 299 300 return PromotedGlobals; 301 } 302 303 Function* cloneFunctionDecl(Module &Dst, const Function &F, 304 ValueToValueMapTy *VMap) { 305 Function *NewF = 306 Function::Create(cast<FunctionType>(F.getValueType()), 307 F.getLinkage(), F.getName(), &Dst); 308 NewF->copyAttributesFrom(&F); 309 310 if (VMap) { 311 (*VMap)[&F] = NewF; 312 auto NewArgI = NewF->arg_begin(); 313 for (auto ArgI = F.arg_begin(), ArgE = F.arg_end(); ArgI != ArgE; 314 ++ArgI, ++NewArgI) 315 (*VMap)[&*ArgI] = &*NewArgI; 316 } 317 318 return NewF; 319 } 320 321 void moveFunctionBody(Function &OrigF, ValueToValueMapTy &VMap, 322 ValueMaterializer *Materializer, 323 Function *NewF) { 324 assert(!OrigF.isDeclaration() && "Nothing to move"); 325 if (!NewF) 326 NewF = cast<Function>(VMap[&OrigF]); 327 else 328 assert(VMap[&OrigF] == NewF && "Incorrect function mapping in VMap."); 329 assert(NewF && "Function mapping missing from VMap."); 330 assert(NewF->getParent() != OrigF.getParent() && 331 "moveFunctionBody should only be used to move bodies between " 332 "modules."); 333 334 SmallVector<ReturnInst *, 8> Returns; // Ignore returns cloned. 335 CloneFunctionInto(NewF, &OrigF, VMap, 336 CloneFunctionChangeType::DifferentModule, Returns, "", 337 nullptr, nullptr, Materializer); 338 OrigF.deleteBody(); 339 } 340 341 GlobalVariable* cloneGlobalVariableDecl(Module &Dst, const GlobalVariable &GV, 342 ValueToValueMapTy *VMap) { 343 GlobalVariable *NewGV = new GlobalVariable( 344 Dst, GV.getValueType(), GV.isConstant(), 345 GV.getLinkage(), nullptr, GV.getName(), nullptr, 346 GV.getThreadLocalMode(), GV.getType()->getAddressSpace()); 347 NewGV->copyAttributesFrom(&GV); 348 if (VMap) 349 (*VMap)[&GV] = NewGV; 350 return NewGV; 351 } 352 353 void moveGlobalVariableInitializer(GlobalVariable &OrigGV, 354 ValueToValueMapTy &VMap, 355 ValueMaterializer *Materializer, 356 GlobalVariable *NewGV) { 357 assert(OrigGV.hasInitializer() && "Nothing to move"); 358 if (!NewGV) 359 NewGV = cast<GlobalVariable>(VMap[&OrigGV]); 360 else 361 assert(VMap[&OrigGV] == NewGV && 362 "Incorrect global variable mapping in VMap."); 363 assert(NewGV->getParent() != OrigGV.getParent() && 364 "moveGlobalVariableInitializer should only be used to move " 365 "initializers between modules"); 366 367 NewGV->setInitializer(MapValue(OrigGV.getInitializer(), VMap, RF_None, 368 nullptr, Materializer)); 369 } 370 371 GlobalAlias* cloneGlobalAliasDecl(Module &Dst, const GlobalAlias &OrigA, 372 ValueToValueMapTy &VMap) { 373 assert(OrigA.getAliasee() && "Original alias doesn't have an aliasee?"); 374 auto *NewA = GlobalAlias::create(OrigA.getValueType(), 375 OrigA.getType()->getPointerAddressSpace(), 376 OrigA.getLinkage(), OrigA.getName(), &Dst); 377 NewA->copyAttributesFrom(&OrigA); 378 VMap[&OrigA] = NewA; 379 return NewA; 380 } 381 382 void cloneModuleFlagsMetadata(Module &Dst, const Module &Src, 383 ValueToValueMapTy &VMap) { 384 auto *MFs = Src.getModuleFlagsMetadata(); 385 if (!MFs) 386 return; 387 for (auto *MF : MFs->operands()) 388 Dst.addModuleFlag(MapMetadata(MF, VMap)); 389 } 390 391 Error addFunctionPointerRelocationsToCurrentSymbol(jitlink::Symbol &Sym, 392 jitlink::LinkGraph &G, 393 MCDisassembler &Disassembler, 394 MCInstrAnalysis &MIA) { 395 // AArch64 appears to already come with the necessary relocations. Among other 396 // architectures, only x86_64 is currently implemented here. 397 if (G.getTargetTriple().getArch() != Triple::x86_64) 398 return Error::success(); 399 400 raw_null_ostream CommentStream; 401 auto &STI = Disassembler.getSubtargetInfo(); 402 403 // Determine the function bounds 404 auto &B = Sym.getBlock(); 405 assert(!B.isZeroFill() && "expected content block"); 406 auto SymAddress = Sym.getAddress(); 407 auto SymStartInBlock = 408 (const uint8_t *)B.getContent().data() + Sym.getOffset(); 409 auto SymSize = Sym.getSize() ? Sym.getSize() : B.getSize() - Sym.getOffset(); 410 auto Content = makeArrayRef(SymStartInBlock, SymSize); 411 412 LLVM_DEBUG(dbgs() << "Adding self-relocations to " << Sym.getName() << "\n"); 413 414 SmallDenseSet<uintptr_t, 8> ExistingRelocations; 415 for (auto &E : B.edges()) { 416 if (E.isRelocation()) 417 ExistingRelocations.insert(E.getOffset()); 418 } 419 420 size_t I = 0; 421 while (I < Content.size()) { 422 MCInst Instr; 423 uint64_t InstrSize = 0; 424 uint64_t InstrStart = SymAddress.getValue() + I; 425 auto DecodeStatus = Disassembler.getInstruction( 426 Instr, InstrSize, Content.drop_front(I), InstrStart, CommentStream); 427 if (DecodeStatus != MCDisassembler::Success) { 428 LLVM_DEBUG(dbgs() << "Aborting due to disassembly failure at address " 429 << InstrStart); 430 return make_error<StringError>( 431 formatv("failed to disassemble at address {0:x16}", InstrStart), 432 inconvertibleErrorCode()); 433 } 434 // Advance to the next instruction. 435 I += InstrSize; 436 437 // Check for a PC-relative address equal to the symbol itself. 438 auto PCRelAddr = 439 MIA.evaluateMemoryOperandAddress(Instr, &STI, InstrStart, InstrSize); 440 if (!PCRelAddr || *PCRelAddr != SymAddress.getValue()) 441 continue; 442 443 auto RelocOffInInstr = 444 MIA.getMemoryOperandRelocationOffset(Instr, InstrSize); 445 if (!RelocOffInInstr || InstrSize - *RelocOffInInstr != 4) { 446 LLVM_DEBUG(dbgs() << "Skipping unknown self-relocation at " 447 << InstrStart); 448 continue; 449 } 450 451 auto RelocOffInBlock = orc::ExecutorAddr(InstrStart) + *RelocOffInInstr - 452 SymAddress + Sym.getOffset(); 453 if (ExistingRelocations.contains(RelocOffInBlock)) 454 continue; 455 456 LLVM_DEBUG(dbgs() << "Adding delta32 self-relocation at " << InstrStart); 457 B.addEdge(jitlink::x86_64::Delta32, RelocOffInBlock, Sym, /*Addend=*/-4); 458 } 459 return Error::success(); 460 } 461 462 } // End namespace orc. 463 } // End namespace llvm. 464