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