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