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); 182 183 // Handle cast of pointer to pointer... 184 if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID()) 185 return getConstantValue(Op); 186 187 // Handle a cast of pointer to any integral type... 188 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 189 return getConstantValue(Op); 190 191 // Handle cast of long to pointer... 192 if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy || 193 Op->getType() == Type::ULongTy)) 194 return getConstantValue(Op); 195 break; 196 } 197 198 case Instruction::Add: 199 if (CE->getOperand(0)->getType() == Type::LongTy || 200 CE->getOperand(0)->getType() == Type::ULongTy) 201 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 202 getConstantValue(CE->getOperand(1)).LongVal; 203 else 204 break; 205 return Result; 206 207 default: 208 break; 209 } 210 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 211 abort(); 212 } 213 214 switch (C->getType()->getPrimitiveID()) { 215 #define GET_CONST_VAL(TY, CLASS) \ 216 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 217 GET_CONST_VAL(Bool , ConstantBool); 218 GET_CONST_VAL(UByte , ConstantUInt); 219 GET_CONST_VAL(SByte , ConstantSInt); 220 GET_CONST_VAL(UShort , ConstantUInt); 221 GET_CONST_VAL(Short , ConstantSInt); 222 GET_CONST_VAL(UInt , ConstantUInt); 223 GET_CONST_VAL(Int , ConstantSInt); 224 GET_CONST_VAL(ULong , ConstantUInt); 225 GET_CONST_VAL(Long , ConstantSInt); 226 GET_CONST_VAL(Float , ConstantFP); 227 GET_CONST_VAL(Double , ConstantFP); 228 #undef GET_CONST_VAL 229 case Type::PointerTyID: 230 if (isa<ConstantPointerNull>(C)) { 231 Result.PointerVal = 0; 232 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 233 if (Function *F = 234 const_cast<Function*>(dyn_cast<Function>(CPR->getValue()))) 235 Result = PTOGV(getPointerToFunctionOrStub(F)); 236 else 237 Result = PTOGV(getOrEmitGlobalVariable( 238 cast<GlobalVariable>(CPR->getValue()))); 239 240 } else { 241 assert(0 && "Unknown constant pointer type!"); 242 } 243 break; 244 default: 245 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 246 abort(); 247 } 248 return Result; 249 } 250 251 /// FIXME: document 252 /// 253 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 254 const Type *Ty) { 255 if (getTargetData().isLittleEndian()) { 256 switch (Ty->getPrimitiveID()) { 257 case Type::BoolTyID: 258 case Type::UByteTyID: 259 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 260 case Type::UShortTyID: 261 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 262 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 263 break; 264 Store4BytesLittleEndian: 265 case Type::FloatTyID: 266 case Type::UIntTyID: 267 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 268 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 269 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 270 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 271 break; 272 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 273 goto Store4BytesLittleEndian; 274 case Type::DoubleTyID: 275 case Type::ULongTyID: 276 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 277 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 278 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 279 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 280 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 281 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 282 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 283 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 284 break; 285 default: 286 std::cout << "Cannot store value of type " << Ty << "!\n"; 287 } 288 } else { 289 switch (Ty->getPrimitiveID()) { 290 case Type::BoolTyID: 291 case Type::UByteTyID: 292 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 293 case Type::UShortTyID: 294 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 295 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 296 break; 297 Store4BytesBigEndian: 298 case Type::FloatTyID: 299 case Type::UIntTyID: 300 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 301 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 302 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 303 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 304 break; 305 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 306 goto Store4BytesBigEndian; 307 case Type::DoubleTyID: 308 case Type::ULongTyID: 309 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 310 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 311 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 312 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 313 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 314 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 315 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 316 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 317 break; 318 default: 319 std::cout << "Cannot store value of type " << Ty << "!\n"; 320 } 321 } 322 } 323 324 /// FIXME: document 325 /// 326 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 327 const Type *Ty) { 328 GenericValue Result; 329 if (getTargetData().isLittleEndian()) { 330 switch (Ty->getPrimitiveID()) { 331 case Type::BoolTyID: 332 case Type::UByteTyID: 333 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 334 case Type::UShortTyID: 335 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 336 ((unsigned)Ptr->Untyped[1] << 8); 337 break; 338 Load4BytesLittleEndian: 339 case Type::FloatTyID: 340 case Type::UIntTyID: 341 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 342 ((unsigned)Ptr->Untyped[1] << 8) | 343 ((unsigned)Ptr->Untyped[2] << 16) | 344 ((unsigned)Ptr->Untyped[3] << 24); 345 break; 346 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 347 goto Load4BytesLittleEndian; 348 case Type::DoubleTyID: 349 case Type::ULongTyID: 350 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 351 ((uint64_t)Ptr->Untyped[1] << 8) | 352 ((uint64_t)Ptr->Untyped[2] << 16) | 353 ((uint64_t)Ptr->Untyped[3] << 24) | 354 ((uint64_t)Ptr->Untyped[4] << 32) | 355 ((uint64_t)Ptr->Untyped[5] << 40) | 356 ((uint64_t)Ptr->Untyped[6] << 48) | 357 ((uint64_t)Ptr->Untyped[7] << 56); 358 break; 359 default: 360 std::cout << "Cannot load value of type " << *Ty << "!\n"; 361 abort(); 362 } 363 } else { 364 switch (Ty->getPrimitiveID()) { 365 case Type::BoolTyID: 366 case Type::UByteTyID: 367 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 368 case Type::UShortTyID: 369 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 370 ((unsigned)Ptr->Untyped[0] << 8); 371 break; 372 Load4BytesBigEndian: 373 case Type::FloatTyID: 374 case Type::UIntTyID: 375 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 376 ((unsigned)Ptr->Untyped[2] << 8) | 377 ((unsigned)Ptr->Untyped[1] << 16) | 378 ((unsigned)Ptr->Untyped[0] << 24); 379 break; 380 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 381 goto Load4BytesBigEndian; 382 case Type::DoubleTyID: 383 case Type::ULongTyID: 384 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 385 ((uint64_t)Ptr->Untyped[6] << 8) | 386 ((uint64_t)Ptr->Untyped[5] << 16) | 387 ((uint64_t)Ptr->Untyped[4] << 24) | 388 ((uint64_t)Ptr->Untyped[3] << 32) | 389 ((uint64_t)Ptr->Untyped[2] << 40) | 390 ((uint64_t)Ptr->Untyped[1] << 48) | 391 ((uint64_t)Ptr->Untyped[0] << 56); 392 break; 393 default: 394 std::cout << "Cannot load value of type " << *Ty << "!\n"; 395 abort(); 396 } 397 } 398 return Result; 399 } 400 401 // InitializeMemory - Recursive function to apply a Constant value into the 402 // specified memory location... 403 // 404 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 405 if (Init->getType()->isFirstClassType()) { 406 GenericValue Val = getConstantValue(Init); 407 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 408 return; 409 } 410 411 switch (Init->getType()->getPrimitiveID()) { 412 case Type::ArrayTyID: { 413 const ConstantArray *CPA = cast<ConstantArray>(Init); 414 const std::vector<Use> &Val = CPA->getValues(); 415 unsigned ElementSize = 416 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 417 for (unsigned i = 0; i < Val.size(); ++i) 418 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 419 return; 420 } 421 422 case Type::StructTyID: { 423 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 424 const StructLayout *SL = 425 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 426 const std::vector<Use> &Val = CPS->getValues(); 427 for (unsigned i = 0; i < Val.size(); ++i) 428 InitializeMemory(cast<Constant>(Val[i].get()), 429 (char*)Addr+SL->MemberOffsets[i]); 430 return; 431 } 432 433 default: 434 std::cerr << "Bad Type: " << Init->getType() << "\n"; 435 assert(0 && "Unknown constant type to initialize memory with!"); 436 } 437 } 438 439 /// EmitGlobals - Emit all of the global variables to memory, storing their 440 /// addresses into GlobalAddress. This must make sure to copy the contents of 441 /// their initializers into the memory. 442 /// 443 void ExecutionEngine::emitGlobals() { 444 const TargetData &TD = getTargetData(); 445 446 // Loop over all of the global variables in the program, allocating the memory 447 // to hold them. 448 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 449 I != E; ++I) 450 if (!I->isExternal()) { 451 // Get the type of the global... 452 const Type *Ty = I->getType()->getElementType(); 453 454 // Allocate some memory for it! 455 unsigned Size = TD.getTypeSize(Ty); 456 addGlobalMapping(I, new char[Size]); 457 } else { 458 // External variable reference. Try to use the dynamic loader to 459 // get a pointer to it. 460 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 461 addGlobalMapping(I, SymAddr); 462 else { 463 std::cerr << "Could not resolve external global address: " 464 << I->getName() << "\n"; 465 abort(); 466 } 467 } 468 469 // Now that all of the globals are set up in memory, loop through them all and 470 // initialize their contents. 471 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 472 I != E; ++I) 473 if (!I->isExternal()) 474 EmitGlobalVariable(I); 475 } 476 477 // EmitGlobalVariable - This method emits the specified global variable to the 478 // address specified in GlobalAddresses, or allocates new memory if it's not 479 // already in the map. 480 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) { 481 void *GA = getPointerToGlobalIfAvailable(GV); 482 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n"); 483 484 const Type *ElTy = GV->getType()->getElementType(); 485 if (GA == 0) { 486 // If it's not already specified, allocate memory for the global. 487 GA = new char[getTargetData().getTypeSize(ElTy)]; 488 addGlobalMapping(GV, GA); 489 } 490 491 InitializeMemory(GV->getInitializer(), GA); 492 NumInitBytes += getTargetData().getTypeSize(ElTy); 493 ++NumGlobals; 494 } 495