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 "Support/Debug.h" 27 #include "Support/Statistic.h" 28 #include "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 GVArgs.push_back(GVArgc); // Arg #0 = argc. 106 GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv. 107 assert(((char **)GVTOP(GVArgs[1]))[0] && "argv[0] was null after CreateArgv"); 108 109 std::vector<std::string> EnvVars; 110 for (unsigned i = 0; envp[i]; ++i) 111 EnvVars.push_back(envp[i]); 112 GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp. 113 return runFunction(Fn, GVArgs).IntVal; 114 } 115 116 117 118 /// If possible, create a JIT, unless the caller specifically requests an 119 /// Interpreter or there's an error. If even an Interpreter cannot be created, 120 /// NULL is returned. 121 /// 122 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 123 bool ForceInterpreter, 124 IntrinsicLowering *IL) { 125 ExecutionEngine *EE = 0; 126 127 // Unless the interpreter was explicitly selected, try making a JIT. 128 if (!ForceInterpreter) 129 EE = JIT::create(MP, IL); 130 131 // If we can't make a JIT, make an interpreter instead. 132 if (EE == 0) { 133 try { 134 Module *M = MP->materializeModule(); 135 try { 136 EE = Interpreter::create(M, IL); 137 } catch (...) { 138 std::cerr << "Error creating the interpreter!\n"; 139 } 140 } catch (std::string& errmsg) { 141 std::cerr << "Error reading the bytecode file: " << errmsg << "\n"; 142 } catch (...) { 143 std::cerr << "Error reading the bytecode file!\n"; 144 } 145 } 146 147 if (EE == 0) delete IL; 148 return EE; 149 } 150 151 /// getPointerToGlobal - This returns the address of the specified global 152 /// value. This may involve code generation if it's a function. 153 /// 154 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 155 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 156 return getPointerToFunction(F); 157 158 assert(GlobalAddressMap[GV] && "Global hasn't had an address allocated yet?"); 159 return GlobalAddressMap[GV]; 160 } 161 162 /// FIXME: document 163 /// 164 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 165 GenericValue Result; 166 167 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 168 switch (CE->getOpcode()) { 169 case Instruction::GetElementPtr: { 170 Result = getConstantValue(CE->getOperand(0)); 171 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 172 uint64_t Offset = 173 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 174 175 Result.LongVal += Offset; 176 return Result; 177 } 178 case Instruction::Cast: { 179 // We only need to handle a few cases here. Almost all casts will 180 // automatically fold, just the ones involving pointers won't. 181 // 182 Constant *Op = CE->getOperand(0); 183 GenericValue GV = getConstantValue(Op); 184 185 // Handle cast of pointer to pointer... 186 if (Op->getType()->getTypeID() == C->getType()->getTypeID()) 187 return GV; 188 189 // Handle a cast of pointer to any integral type... 190 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 191 return GV; 192 193 // Handle cast of integer to a pointer... 194 if (isa<PointerType>(C->getType()) && Op->getType()->isIntegral()) 195 switch (Op->getType()->getTypeID()) { 196 case Type::BoolTyID: return PTOGV((void*)(uintptr_t)GV.BoolVal); 197 case Type::SByteTyID: return PTOGV((void*)( intptr_t)GV.SByteVal); 198 case Type::UByteTyID: return PTOGV((void*)(uintptr_t)GV.UByteVal); 199 case Type::ShortTyID: return PTOGV((void*)( intptr_t)GV.ShortVal); 200 case Type::UShortTyID: return PTOGV((void*)(uintptr_t)GV.UShortVal); 201 case Type::IntTyID: return PTOGV((void*)( intptr_t)GV.IntVal); 202 case Type::UIntTyID: return PTOGV((void*)(uintptr_t)GV.UIntVal); 203 case Type::LongTyID: return PTOGV((void*)( intptr_t)GV.LongVal); 204 case Type::ULongTyID: return PTOGV((void*)(uintptr_t)GV.ULongVal); 205 default: assert(0 && "Unknown integral type!"); 206 } 207 break; 208 } 209 210 case Instruction::Add: 211 switch (CE->getOperand(0)->getType()->getTypeID()) { 212 default: assert(0 && "Bad add type!"); abort(); 213 case Type::LongTyID: 214 case Type::ULongTyID: 215 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 216 getConstantValue(CE->getOperand(1)).LongVal; 217 break; 218 case Type::IntTyID: 219 case Type::UIntTyID: 220 Result.IntVal = getConstantValue(CE->getOperand(0)).IntVal + 221 getConstantValue(CE->getOperand(1)).IntVal; 222 break; 223 case Type::ShortTyID: 224 case Type::UShortTyID: 225 Result.ShortVal = getConstantValue(CE->getOperand(0)).ShortVal + 226 getConstantValue(CE->getOperand(1)).ShortVal; 227 break; 228 case Type::SByteTyID: 229 case Type::UByteTyID: 230 Result.SByteVal = getConstantValue(CE->getOperand(0)).SByteVal + 231 getConstantValue(CE->getOperand(1)).SByteVal; 232 break; 233 case Type::FloatTyID: 234 Result.FloatVal = getConstantValue(CE->getOperand(0)).FloatVal + 235 getConstantValue(CE->getOperand(1)).FloatVal; 236 break; 237 case Type::DoubleTyID: 238 Result.DoubleVal = getConstantValue(CE->getOperand(0)).DoubleVal + 239 getConstantValue(CE->getOperand(1)).DoubleVal; 240 break; 241 } 242 return Result; 243 default: 244 break; 245 } 246 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 247 abort(); 248 } 249 250 switch (C->getType()->getTypeID()) { 251 #define GET_CONST_VAL(TY, CLASS) \ 252 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 253 GET_CONST_VAL(Bool , ConstantBool); 254 GET_CONST_VAL(UByte , ConstantUInt); 255 GET_CONST_VAL(SByte , ConstantSInt); 256 GET_CONST_VAL(UShort , ConstantUInt); 257 GET_CONST_VAL(Short , ConstantSInt); 258 GET_CONST_VAL(UInt , ConstantUInt); 259 GET_CONST_VAL(Int , ConstantSInt); 260 GET_CONST_VAL(ULong , ConstantUInt); 261 GET_CONST_VAL(Long , ConstantSInt); 262 GET_CONST_VAL(Float , ConstantFP); 263 GET_CONST_VAL(Double , ConstantFP); 264 #undef GET_CONST_VAL 265 case Type::PointerTyID: 266 if (isa<ConstantPointerNull>(C)) 267 Result.PointerVal = 0; 268 else if (const Function *F = dyn_cast<Function>(C)) 269 Result = PTOGV(getPointerToFunctionOrStub(const_cast<Function*>(F))); 270 else if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C)) 271 Result = PTOGV(getOrEmitGlobalVariable(const_cast<GlobalVariable*>(GV))); 272 else 273 assert(0 && "Unknown constant pointer type!"); 274 break; 275 default: 276 std::cout << "ERROR: Constant unimp for type: " << *C->getType() << "\n"; 277 abort(); 278 } 279 return Result; 280 } 281 282 /// FIXME: document 283 /// 284 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 285 const Type *Ty) { 286 if (getTargetData().isLittleEndian()) { 287 switch (Ty->getTypeID()) { 288 case Type::BoolTyID: 289 case Type::UByteTyID: 290 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 291 case Type::UShortTyID: 292 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 293 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 294 break; 295 Store4BytesLittleEndian: 296 case Type::FloatTyID: 297 case Type::UIntTyID: 298 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 299 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 300 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 301 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 302 break; 303 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 304 goto Store4BytesLittleEndian; 305 case Type::DoubleTyID: 306 case Type::ULongTyID: 307 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 308 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 309 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 310 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 311 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 312 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 313 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 314 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 315 break; 316 default: 317 std::cout << "Cannot store value of type " << *Ty << "!\n"; 318 } 319 } else { 320 switch (Ty->getTypeID()) { 321 case Type::BoolTyID: 322 case Type::UByteTyID: 323 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 324 case Type::UShortTyID: 325 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 326 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 327 break; 328 Store4BytesBigEndian: 329 case Type::FloatTyID: 330 case Type::UIntTyID: 331 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 332 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 333 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 334 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 335 break; 336 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 337 goto Store4BytesBigEndian; 338 case Type::DoubleTyID: 339 case Type::ULongTyID: 340 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 341 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 342 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 343 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 344 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 345 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 346 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 347 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 348 break; 349 default: 350 std::cout << "Cannot store value of type " << *Ty << "!\n"; 351 } 352 } 353 } 354 355 /// FIXME: document 356 /// 357 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 358 const Type *Ty) { 359 GenericValue Result; 360 if (getTargetData().isLittleEndian()) { 361 switch (Ty->getTypeID()) { 362 case Type::BoolTyID: 363 case Type::UByteTyID: 364 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 365 case Type::UShortTyID: 366 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 367 ((unsigned)Ptr->Untyped[1] << 8); 368 break; 369 Load4BytesLittleEndian: 370 case Type::FloatTyID: 371 case Type::UIntTyID: 372 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 373 ((unsigned)Ptr->Untyped[1] << 8) | 374 ((unsigned)Ptr->Untyped[2] << 16) | 375 ((unsigned)Ptr->Untyped[3] << 24); 376 break; 377 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 378 goto Load4BytesLittleEndian; 379 case Type::DoubleTyID: 380 case Type::ULongTyID: 381 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 382 ((uint64_t)Ptr->Untyped[1] << 8) | 383 ((uint64_t)Ptr->Untyped[2] << 16) | 384 ((uint64_t)Ptr->Untyped[3] << 24) | 385 ((uint64_t)Ptr->Untyped[4] << 32) | 386 ((uint64_t)Ptr->Untyped[5] << 40) | 387 ((uint64_t)Ptr->Untyped[6] << 48) | 388 ((uint64_t)Ptr->Untyped[7] << 56); 389 break; 390 default: 391 std::cout << "Cannot load value of type " << *Ty << "!\n"; 392 abort(); 393 } 394 } else { 395 switch (Ty->getTypeID()) { 396 case Type::BoolTyID: 397 case Type::UByteTyID: 398 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 399 case Type::UShortTyID: 400 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 401 ((unsigned)Ptr->Untyped[0] << 8); 402 break; 403 Load4BytesBigEndian: 404 case Type::FloatTyID: 405 case Type::UIntTyID: 406 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 407 ((unsigned)Ptr->Untyped[2] << 8) | 408 ((unsigned)Ptr->Untyped[1] << 16) | 409 ((unsigned)Ptr->Untyped[0] << 24); 410 break; 411 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 412 goto Load4BytesBigEndian; 413 case Type::DoubleTyID: 414 case Type::ULongTyID: 415 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 416 ((uint64_t)Ptr->Untyped[6] << 8) | 417 ((uint64_t)Ptr->Untyped[5] << 16) | 418 ((uint64_t)Ptr->Untyped[4] << 24) | 419 ((uint64_t)Ptr->Untyped[3] << 32) | 420 ((uint64_t)Ptr->Untyped[2] << 40) | 421 ((uint64_t)Ptr->Untyped[1] << 48) | 422 ((uint64_t)Ptr->Untyped[0] << 56); 423 break; 424 default: 425 std::cout << "Cannot load value of type " << *Ty << "!\n"; 426 abort(); 427 } 428 } 429 return Result; 430 } 431 432 // InitializeMemory - Recursive function to apply a Constant value into the 433 // specified memory location... 434 // 435 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 436 if (Init->getType()->isFirstClassType()) { 437 GenericValue Val = getConstantValue(Init); 438 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 439 return; 440 } else if (isa<ConstantAggregateZero>(Init)) { 441 unsigned Size = getTargetData().getTypeSize(Init->getType()); 442 memset(Addr, 0, Size); 443 return; 444 } 445 446 switch (Init->getType()->getTypeID()) { 447 case Type::ArrayTyID: { 448 const ConstantArray *CPA = cast<ConstantArray>(Init); 449 unsigned ElementSize = 450 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 451 for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i) 452 InitializeMemory(CPA->getOperand(i), (char*)Addr+i*ElementSize); 453 return; 454 } 455 456 case Type::StructTyID: { 457 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 458 const StructLayout *SL = 459 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 460 for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i) 461 InitializeMemory(CPS->getOperand(i), (char*)Addr+SL->MemberOffsets[i]); 462 return; 463 } 464 465 default: 466 std::cerr << "Bad Type: " << *Init->getType() << "\n"; 467 assert(0 && "Unknown constant type to initialize memory with!"); 468 } 469 } 470 471 /// EmitGlobals - Emit all of the global variables to memory, storing their 472 /// addresses into GlobalAddress. This must make sure to copy the contents of 473 /// their initializers into the memory. 474 /// 475 void ExecutionEngine::emitGlobals() { 476 const TargetData &TD = getTargetData(); 477 478 // Loop over all of the global variables in the program, allocating the memory 479 // to hold them. 480 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 481 I != E; ++I) 482 if (!I->isExternal()) { 483 // Get the type of the global... 484 const Type *Ty = I->getType()->getElementType(); 485 486 // Allocate some memory for it! 487 unsigned Size = TD.getTypeSize(Ty); 488 addGlobalMapping(I, new char[Size]); 489 } else { 490 // External variable reference. Try to use the dynamic loader to 491 // get a pointer to it. 492 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 493 addGlobalMapping(I, SymAddr); 494 else { 495 std::cerr << "Could not resolve external global address: " 496 << I->getName() << "\n"; 497 abort(); 498 } 499 } 500 501 // Now that all of the globals are set up in memory, loop through them all and 502 // initialize their contents. 503 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 504 I != E; ++I) 505 if (!I->isExternal()) 506 EmitGlobalVariable(I); 507 } 508 509 // EmitGlobalVariable - This method emits the specified global variable to the 510 // address specified in GlobalAddresses, or allocates new memory if it's not 511 // already in the map. 512 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) { 513 void *GA = getPointerToGlobalIfAvailable(GV); 514 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n"); 515 516 const Type *ElTy = GV->getType()->getElementType(); 517 if (GA == 0) { 518 // If it's not already specified, allocate memory for the global. 519 GA = new char[getTargetData().getTypeSize(ElTy)]; 520 addGlobalMapping(GV, GA); 521 } 522 523 InitializeMemory(GV->getInitializer(), GA); 524 NumInitBytes += getTargetData().getTypeSize(ElTy); 525 ++NumGlobals; 526 } 527