1 //===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file was developed by the LLVM research group and is distributed under 6 // the University of Illinois Open Source License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the common interface used by the various execution engine 11 // subclasses. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #define DEBUG_TYPE "jit" 16 #include "Interpreter/Interpreter.h" 17 #include "JIT/JIT.h" 18 #include "llvm/Constants.h" 19 #include "llvm/DerivedTypes.h" 20 #include "llvm/Module.h" 21 #include "llvm/ModuleProvider.h" 22 #include "llvm/CodeGen/IntrinsicLowering.h" 23 #include "llvm/ExecutionEngine/ExecutionEngine.h" 24 #include "llvm/ExecutionEngine/GenericValue.h" 25 #include "llvm/Target/TargetData.h" 26 #include "llvm/Support/Debug.h" 27 #include "llvm/ADT/Statistic.h" 28 #include "llvm/Support/DynamicLinker.h" 29 using namespace llvm; 30 31 namespace { 32 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized"); 33 Statistic<> NumGlobals ("lli", "Number of global vars initialized"); 34 } 35 36 ExecutionEngine::ExecutionEngine(ModuleProvider *P) : 37 CurMod(*P->getModule()), MP(P) { 38 assert(P && "ModuleProvider is null?"); 39 } 40 41 ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) { 42 assert(M && "Module is null?"); 43 } 44 45 ExecutionEngine::~ExecutionEngine() { 46 delete MP; 47 } 48 49 /// getGlobalValueAtAddress - Return the LLVM global value object that starts 50 /// at the specified address. 51 /// 52 const GlobalValue *ExecutionEngine::getGlobalValueAtAddress(void *Addr) { 53 // If we haven't computed the reverse mapping yet, do so first. 54 if (GlobalAddressReverseMap.empty()) { 55 for (std::map<const GlobalValue*, void *>::iterator I = 56 GlobalAddressMap.begin(), E = GlobalAddressMap.end(); I != E; ++I) 57 GlobalAddressReverseMap.insert(std::make_pair(I->second, I->first)); 58 } 59 60 std::map<void *, const GlobalValue*>::iterator I = 61 GlobalAddressReverseMap.find(Addr); 62 return I != GlobalAddressReverseMap.end() ? I->second : 0; 63 } 64 65 // CreateArgv - Turn a vector of strings into a nice argv style array of 66 // pointers to null terminated strings. 67 // 68 static void *CreateArgv(ExecutionEngine *EE, 69 const std::vector<std::string> &InputArgv) { 70 unsigned PtrSize = EE->getTargetData().getPointerSize(); 71 char *Result = new char[(InputArgv.size()+1)*PtrSize]; 72 73 DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n"); 74 const Type *SBytePtr = PointerType::get(Type::SByteTy); 75 76 for (unsigned i = 0; i != InputArgv.size(); ++i) { 77 unsigned Size = InputArgv[i].size()+1; 78 char *Dest = new char[Size]; 79 DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n"); 80 81 std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest); 82 Dest[Size-1] = 0; 83 84 // Endian safe: Result[i] = (PointerTy)Dest; 85 EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i*PtrSize), 86 SBytePtr); 87 } 88 89 // Null terminate it 90 EE->StoreValueToMemory(PTOGV(0), 91 (GenericValue*)(Result+InputArgv.size()*PtrSize), 92 SBytePtr); 93 return Result; 94 } 95 96 /// runFunctionAsMain - This is a helper function which wraps runFunction to 97 /// handle the common task of starting up main with the specified argc, argv, 98 /// and envp parameters. 99 int ExecutionEngine::runFunctionAsMain(Function *Fn, 100 const std::vector<std::string> &argv, 101 const char * const * envp) { 102 std::vector<GenericValue> GVArgs; 103 GenericValue GVArgc; 104 GVArgc.IntVal = argv.size(); 105 unsigned NumArgs = Fn->getFunctionType()->getNumParams(); 106 if (NumArgs) { 107 GVArgs.push_back(GVArgc); // Arg #0 = argc. 108 if (NumArgs > 1) { 109 GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv. 110 assert(((char **)GVTOP(GVArgs[1]))[0] && 111 "argv[0] was null after CreateArgv"); 112 if (NumArgs > 2) { 113 std::vector<std::string> EnvVars; 114 for (unsigned i = 0; envp[i]; ++i) 115 EnvVars.push_back(envp[i]); 116 GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp. 117 } 118 } 119 } 120 return runFunction(Fn, GVArgs).IntVal; 121 } 122 123 124 125 /// If possible, create a JIT, unless the caller specifically requests an 126 /// Interpreter or there's an error. If even an Interpreter cannot be created, 127 /// NULL is returned. 128 /// 129 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 130 bool ForceInterpreter, 131 IntrinsicLowering *IL) { 132 ExecutionEngine *EE = 0; 133 134 // Unless the interpreter was explicitly selected, try making a JIT. 135 if (!ForceInterpreter) 136 EE = JIT::create(MP, IL); 137 138 // If we can't make a JIT, make an interpreter instead. 139 if (EE == 0) { 140 try { 141 Module *M = MP->materializeModule(); 142 try { 143 EE = Interpreter::create(M, IL); 144 } catch (...) { 145 std::cerr << "Error creating the interpreter!\n"; 146 } 147 } catch (std::string& errmsg) { 148 std::cerr << "Error reading the bytecode file: " << errmsg << "\n"; 149 } catch (...) { 150 std::cerr << "Error reading the bytecode file!\n"; 151 } 152 } 153 154 if (EE == 0) delete IL; 155 return EE; 156 } 157 158 /// getPointerToGlobal - This returns the address of the specified global 159 /// value. This may involve code generation if it's a function. 160 /// 161 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 162 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 163 return getPointerToFunction(F); 164 165 assert(GlobalAddressMap[GV] && "Global hasn't had an address allocated yet?"); 166 return GlobalAddressMap[GV]; 167 } 168 169 /// FIXME: document 170 /// 171 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 172 GenericValue Result; 173 if (isa<UndefValue>(C)) return Result; 174 175 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 176 switch (CE->getOpcode()) { 177 case Instruction::GetElementPtr: { 178 Result = getConstantValue(CE->getOperand(0)); 179 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 180 uint64_t Offset = 181 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 182 183 Result.LongVal += Offset; 184 return Result; 185 } 186 case Instruction::Cast: { 187 // We only need to handle a few cases here. Almost all casts will 188 // automatically fold, just the ones involving pointers won't. 189 // 190 Constant *Op = CE->getOperand(0); 191 GenericValue GV = getConstantValue(Op); 192 193 // Handle cast of pointer to pointer... 194 if (Op->getType()->getTypeID() == C->getType()->getTypeID()) 195 return GV; 196 197 // Handle a cast of pointer to any integral type... 198 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 199 return GV; 200 201 // Handle cast of integer to a pointer... 202 if (isa<PointerType>(C->getType()) && Op->getType()->isIntegral()) 203 switch (Op->getType()->getTypeID()) { 204 case Type::BoolTyID: return PTOGV((void*)(uintptr_t)GV.BoolVal); 205 case Type::SByteTyID: return PTOGV((void*)( intptr_t)GV.SByteVal); 206 case Type::UByteTyID: return PTOGV((void*)(uintptr_t)GV.UByteVal); 207 case Type::ShortTyID: return PTOGV((void*)( intptr_t)GV.ShortVal); 208 case Type::UShortTyID: return PTOGV((void*)(uintptr_t)GV.UShortVal); 209 case Type::IntTyID: return PTOGV((void*)( intptr_t)GV.IntVal); 210 case Type::UIntTyID: return PTOGV((void*)(uintptr_t)GV.UIntVal); 211 case Type::LongTyID: return PTOGV((void*)( intptr_t)GV.LongVal); 212 case Type::ULongTyID: return PTOGV((void*)(uintptr_t)GV.ULongVal); 213 default: assert(0 && "Unknown integral type!"); 214 } 215 break; 216 } 217 218 case Instruction::Add: 219 switch (CE->getOperand(0)->getType()->getTypeID()) { 220 default: assert(0 && "Bad add type!"); abort(); 221 case Type::LongTyID: 222 case Type::ULongTyID: 223 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 224 getConstantValue(CE->getOperand(1)).LongVal; 225 break; 226 case Type::IntTyID: 227 case Type::UIntTyID: 228 Result.IntVal = getConstantValue(CE->getOperand(0)).IntVal + 229 getConstantValue(CE->getOperand(1)).IntVal; 230 break; 231 case Type::ShortTyID: 232 case Type::UShortTyID: 233 Result.ShortVal = getConstantValue(CE->getOperand(0)).ShortVal + 234 getConstantValue(CE->getOperand(1)).ShortVal; 235 break; 236 case Type::SByteTyID: 237 case Type::UByteTyID: 238 Result.SByteVal = getConstantValue(CE->getOperand(0)).SByteVal + 239 getConstantValue(CE->getOperand(1)).SByteVal; 240 break; 241 case Type::FloatTyID: 242 Result.FloatVal = getConstantValue(CE->getOperand(0)).FloatVal + 243 getConstantValue(CE->getOperand(1)).FloatVal; 244 break; 245 case Type::DoubleTyID: 246 Result.DoubleVal = getConstantValue(CE->getOperand(0)).DoubleVal + 247 getConstantValue(CE->getOperand(1)).DoubleVal; 248 break; 249 } 250 return Result; 251 default: 252 break; 253 } 254 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 255 abort(); 256 } 257 258 switch (C->getType()->getTypeID()) { 259 #define GET_CONST_VAL(TY, CLASS) \ 260 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 261 GET_CONST_VAL(Bool , ConstantBool); 262 GET_CONST_VAL(UByte , ConstantUInt); 263 GET_CONST_VAL(SByte , ConstantSInt); 264 GET_CONST_VAL(UShort , ConstantUInt); 265 GET_CONST_VAL(Short , ConstantSInt); 266 GET_CONST_VAL(UInt , ConstantUInt); 267 GET_CONST_VAL(Int , ConstantSInt); 268 GET_CONST_VAL(ULong , ConstantUInt); 269 GET_CONST_VAL(Long , ConstantSInt); 270 GET_CONST_VAL(Float , ConstantFP); 271 GET_CONST_VAL(Double , ConstantFP); 272 #undef GET_CONST_VAL 273 case Type::PointerTyID: 274 if (isa<ConstantPointerNull>(C)) 275 Result.PointerVal = 0; 276 else if (const Function *F = dyn_cast<Function>(C)) 277 Result = PTOGV(getPointerToFunctionOrStub(const_cast<Function*>(F))); 278 else if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C)) 279 Result = PTOGV(getOrEmitGlobalVariable(const_cast<GlobalVariable*>(GV))); 280 else 281 assert(0 && "Unknown constant pointer type!"); 282 break; 283 default: 284 std::cout << "ERROR: Constant unimp for type: " << *C->getType() << "\n"; 285 abort(); 286 } 287 return Result; 288 } 289 290 /// FIXME: document 291 /// 292 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 293 const Type *Ty) { 294 if (getTargetData().isLittleEndian()) { 295 switch (Ty->getTypeID()) { 296 case Type::BoolTyID: 297 case Type::UByteTyID: 298 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 299 case Type::UShortTyID: 300 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 301 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 302 break; 303 Store4BytesLittleEndian: 304 case Type::FloatTyID: 305 case Type::UIntTyID: 306 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 307 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 308 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 309 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 310 break; 311 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 312 goto Store4BytesLittleEndian; 313 case Type::DoubleTyID: 314 case Type::ULongTyID: 315 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 316 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 317 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 318 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 319 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 320 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 321 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 322 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 323 break; 324 default: 325 std::cout << "Cannot store value of type " << *Ty << "!\n"; 326 } 327 } else { 328 switch (Ty->getTypeID()) { 329 case Type::BoolTyID: 330 case Type::UByteTyID: 331 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 332 case Type::UShortTyID: 333 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 334 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 335 break; 336 Store4BytesBigEndian: 337 case Type::FloatTyID: 338 case Type::UIntTyID: 339 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 340 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 341 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 342 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 343 break; 344 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 345 goto Store4BytesBigEndian; 346 case Type::DoubleTyID: 347 case Type::ULongTyID: 348 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 349 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 350 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 351 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 352 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 353 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 354 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 355 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 356 break; 357 default: 358 std::cout << "Cannot store value of type " << *Ty << "!\n"; 359 } 360 } 361 } 362 363 /// FIXME: document 364 /// 365 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 366 const Type *Ty) { 367 GenericValue Result; 368 if (getTargetData().isLittleEndian()) { 369 switch (Ty->getTypeID()) { 370 case Type::BoolTyID: 371 case Type::UByteTyID: 372 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 373 case Type::UShortTyID: 374 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 375 ((unsigned)Ptr->Untyped[1] << 8); 376 break; 377 Load4BytesLittleEndian: 378 case Type::FloatTyID: 379 case Type::UIntTyID: 380 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 381 ((unsigned)Ptr->Untyped[1] << 8) | 382 ((unsigned)Ptr->Untyped[2] << 16) | 383 ((unsigned)Ptr->Untyped[3] << 24); 384 break; 385 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 386 goto Load4BytesLittleEndian; 387 case Type::DoubleTyID: 388 case Type::ULongTyID: 389 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 390 ((uint64_t)Ptr->Untyped[1] << 8) | 391 ((uint64_t)Ptr->Untyped[2] << 16) | 392 ((uint64_t)Ptr->Untyped[3] << 24) | 393 ((uint64_t)Ptr->Untyped[4] << 32) | 394 ((uint64_t)Ptr->Untyped[5] << 40) | 395 ((uint64_t)Ptr->Untyped[6] << 48) | 396 ((uint64_t)Ptr->Untyped[7] << 56); 397 break; 398 default: 399 std::cout << "Cannot load value of type " << *Ty << "!\n"; 400 abort(); 401 } 402 } else { 403 switch (Ty->getTypeID()) { 404 case Type::BoolTyID: 405 case Type::UByteTyID: 406 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 407 case Type::UShortTyID: 408 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 409 ((unsigned)Ptr->Untyped[0] << 8); 410 break; 411 Load4BytesBigEndian: 412 case Type::FloatTyID: 413 case Type::UIntTyID: 414 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 415 ((unsigned)Ptr->Untyped[2] << 8) | 416 ((unsigned)Ptr->Untyped[1] << 16) | 417 ((unsigned)Ptr->Untyped[0] << 24); 418 break; 419 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 420 goto Load4BytesBigEndian; 421 case Type::DoubleTyID: 422 case Type::ULongTyID: 423 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 424 ((uint64_t)Ptr->Untyped[6] << 8) | 425 ((uint64_t)Ptr->Untyped[5] << 16) | 426 ((uint64_t)Ptr->Untyped[4] << 24) | 427 ((uint64_t)Ptr->Untyped[3] << 32) | 428 ((uint64_t)Ptr->Untyped[2] << 40) | 429 ((uint64_t)Ptr->Untyped[1] << 48) | 430 ((uint64_t)Ptr->Untyped[0] << 56); 431 break; 432 default: 433 std::cout << "Cannot load value of type " << *Ty << "!\n"; 434 abort(); 435 } 436 } 437 return Result; 438 } 439 440 // InitializeMemory - Recursive function to apply a Constant value into the 441 // specified memory location... 442 // 443 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 444 if (isa<UndefValue>(Init)) { 445 // FIXME: THIS SHOULD NOT BE NEEDED. 446 unsigned Size = getTargetData().getTypeSize(Init->getType()); 447 memset(Addr, 0, Size); 448 return; 449 } else if (Init->getType()->isFirstClassType()) { 450 GenericValue Val = getConstantValue(Init); 451 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 452 return; 453 } else if (isa<ConstantAggregateZero>(Init)) { 454 unsigned Size = getTargetData().getTypeSize(Init->getType()); 455 memset(Addr, 0, Size); 456 return; 457 } 458 459 switch (Init->getType()->getTypeID()) { 460 case Type::ArrayTyID: { 461 const ConstantArray *CPA = cast<ConstantArray>(Init); 462 unsigned ElementSize = 463 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 464 for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i) 465 InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize); 466 return; 467 } 468 469 case Type::StructTyID: { 470 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 471 const StructLayout *SL = 472 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 473 for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i) 474 InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->MemberOffsets[i]); 475 return; 476 } 477 478 default: 479 std::cerr << "Bad Type: " << *Init->getType() << "\n"; 480 assert(0 && "Unknown constant type to initialize memory with!"); 481 } 482 } 483 484 /// EmitGlobals - Emit all of the global variables to memory, storing their 485 /// addresses into GlobalAddress. This must make sure to copy the contents of 486 /// their initializers into the memory. 487 /// 488 void ExecutionEngine::emitGlobals() { 489 const TargetData &TD = getTargetData(); 490 491 // Loop over all of the global variables in the program, allocating the memory 492 // to hold them. 493 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 494 I != E; ++I) 495 if (!I->isExternal()) { 496 // Get the type of the global... 497 const Type *Ty = I->getType()->getElementType(); 498 499 // Allocate some memory for it! 500 unsigned Size = TD.getTypeSize(Ty); 501 addGlobalMapping(I, new char[Size]); 502 } else { 503 // External variable reference. Try to use the dynamic loader to 504 // get a pointer to it. 505 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 506 addGlobalMapping(I, SymAddr); 507 else { 508 std::cerr << "Could not resolve external global address: " 509 << I->getName() << "\n"; 510 abort(); 511 } 512 } 513 514 // Now that all of the globals are set up in memory, loop through them all and 515 // initialize their contents. 516 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 517 I != E; ++I) 518 if (!I->isExternal()) 519 EmitGlobalVariable(I); 520 } 521 522 // EmitGlobalVariable - This method emits the specified global variable to the 523 // address specified in GlobalAddresses, or allocates new memory if it's not 524 // already in the map. 525 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) { 526 void *GA = getPointerToGlobalIfAvailable(GV); 527 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n"); 528 529 const Type *ElTy = GV->getType()->getElementType(); 530 unsigned GVSize = getTargetData().getTypeSize(ElTy); 531 if (GA == 0) { 532 // If it's not already specified, allocate memory for the global. 533 GA = new char[GVSize]; 534 addGlobalMapping(GV, GA); 535 } 536 537 InitializeMemory(GV->getInitializer(), GA); 538 NumInitBytes += GVSize; 539 ++NumGlobals; 540 } 541