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/ExecutionEngine/ExecutionEngine.h" 23 #include "llvm/ExecutionEngine/GenericValue.h" 24 #include "llvm/Target/TargetData.h" 25 #include "Support/Debug.h" 26 #include "Support/Statistic.h" 27 #include "Support/DynamicLinker.h" 28 #include "Config/dlfcn.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 50 // CreateArgv - Turn a vector of strings into a nice argv style array of 51 // pointers to null terminated strings. 52 // 53 static void *CreateArgv(ExecutionEngine *EE, 54 const std::vector<std::string> &InputArgv) { 55 unsigned PtrSize = EE->getTargetData().getPointerSize(); 56 char *Result = new char[(InputArgv.size()+1)*PtrSize]; 57 58 DEBUG(std::cerr << "ARGV = " << (void*)Result << "\n"); 59 const Type *SBytePtr = PointerType::get(Type::SByteTy); 60 61 for (unsigned i = 0; i != InputArgv.size(); ++i) { 62 unsigned Size = InputArgv[i].size()+1; 63 char *Dest = new char[Size]; 64 DEBUG(std::cerr << "ARGV[" << i << "] = " << (void*)Dest << "\n"); 65 66 std::copy(InputArgv[i].begin(), InputArgv[i].end(), Dest); 67 Dest[Size-1] = 0; 68 69 // Endian safe: Result[i] = (PointerTy)Dest; 70 EE->StoreValueToMemory(PTOGV(Dest), (GenericValue*)(Result+i*PtrSize), 71 SBytePtr); 72 } 73 74 // Null terminate it 75 EE->StoreValueToMemory(PTOGV(0), 76 (GenericValue*)(Result+InputArgv.size()*PtrSize), 77 SBytePtr); 78 return Result; 79 } 80 81 /// runFunctionAsMain - This is a helper function which wraps runFunction to 82 /// handle the common task of starting up main with the specified argc, argv, 83 /// and envp parameters. 84 int ExecutionEngine::runFunctionAsMain(Function *Fn, 85 const std::vector<std::string> &argv, 86 const char * const * envp) { 87 std::vector<GenericValue> GVArgs; 88 GenericValue GVArgc; 89 GVArgc.IntVal = argv.size(); 90 GVArgs.push_back(GVArgc); // Arg #0 = argc. 91 GVArgs.push_back(PTOGV(CreateArgv(this, argv))); // Arg #1 = argv. 92 assert(((char **)GVTOP(GVArgs[1]))[0] && "argv[0] was null after CreateArgv"); 93 94 std::vector<std::string> EnvVars; 95 for (unsigned i = 0; envp[i]; ++i) 96 EnvVars.push_back(envp[i]); 97 GVArgs.push_back(PTOGV(CreateArgv(this, EnvVars))); // Arg #2 = envp. 98 return runFunction(Fn, GVArgs).IntVal; 99 } 100 101 102 103 /// If possible, create a JIT, unless the caller specifically requests an 104 /// Interpreter or there's an error. If even an Interpreter cannot be created, 105 /// NULL is returned. 106 /// 107 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 108 bool ForceInterpreter) { 109 ExecutionEngine *EE = 0; 110 111 // Unless the interpreter was explicitly selected, make a JIT. 112 if (!ForceInterpreter) 113 EE = JIT::create(MP); 114 115 // If we can't make a JIT, make an interpreter instead. 116 try { 117 if (EE == 0) 118 EE = Interpreter::create(MP->materializeModule()); 119 } catch (...) { 120 EE = 0; 121 } 122 return EE; 123 } 124 125 /// getPointerToGlobal - This returns the address of the specified global 126 /// value. This may involve code generation if it's a function. 127 /// 128 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 129 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 130 return getPointerToFunction(F); 131 132 assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?"); 133 return GlobalAddress[GV]; 134 } 135 136 /// FIXME: document 137 /// 138 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 139 GenericValue Result; 140 141 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 142 switch (CE->getOpcode()) { 143 case Instruction::GetElementPtr: { 144 Result = getConstantValue(CE->getOperand(0)); 145 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 146 uint64_t Offset = 147 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 148 149 Result.LongVal += Offset; 150 return Result; 151 } 152 case Instruction::Cast: { 153 // We only need to handle a few cases here. Almost all casts will 154 // automatically fold, just the ones involving pointers won't. 155 // 156 Constant *Op = CE->getOperand(0); 157 158 // Handle cast of pointer to pointer... 159 if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID()) 160 return getConstantValue(Op); 161 162 // Handle a cast of pointer to any integral type... 163 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 164 return getConstantValue(Op); 165 166 // Handle cast of long to pointer... 167 if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy || 168 Op->getType() == Type::ULongTy)) 169 return getConstantValue(Op); 170 break; 171 } 172 173 case Instruction::Add: 174 if (CE->getOperand(0)->getType() == Type::LongTy || 175 CE->getOperand(0)->getType() == Type::ULongTy) 176 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 177 getConstantValue(CE->getOperand(1)).LongVal; 178 else 179 break; 180 return Result; 181 182 default: 183 break; 184 } 185 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 186 abort(); 187 } 188 189 switch (C->getType()->getPrimitiveID()) { 190 #define GET_CONST_VAL(TY, CLASS) \ 191 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 192 GET_CONST_VAL(Bool , ConstantBool); 193 GET_CONST_VAL(UByte , ConstantUInt); 194 GET_CONST_VAL(SByte , ConstantSInt); 195 GET_CONST_VAL(UShort , ConstantUInt); 196 GET_CONST_VAL(Short , ConstantSInt); 197 GET_CONST_VAL(UInt , ConstantUInt); 198 GET_CONST_VAL(Int , ConstantSInt); 199 GET_CONST_VAL(ULong , ConstantUInt); 200 GET_CONST_VAL(Long , ConstantSInt); 201 GET_CONST_VAL(Float , ConstantFP); 202 GET_CONST_VAL(Double , ConstantFP); 203 #undef GET_CONST_VAL 204 case Type::PointerTyID: 205 if (isa<ConstantPointerNull>(C)) { 206 Result.PointerVal = 0; 207 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 208 if (Function *F = 209 const_cast<Function*>(dyn_cast<Function>(CPR->getValue()))) 210 Result = PTOGV(getPointerToFunctionOrStub(F)); 211 else 212 Result = PTOGV(getOrEmitGlobalVariable( 213 cast<GlobalVariable>(CPR->getValue()))); 214 215 } else { 216 assert(0 && "Unknown constant pointer type!"); 217 } 218 break; 219 default: 220 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 221 abort(); 222 } 223 return Result; 224 } 225 226 /// FIXME: document 227 /// 228 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 229 const Type *Ty) { 230 if (getTargetData().isLittleEndian()) { 231 switch (Ty->getPrimitiveID()) { 232 case Type::BoolTyID: 233 case Type::UByteTyID: 234 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 235 case Type::UShortTyID: 236 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 237 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 238 break; 239 Store4BytesLittleEndian: 240 case Type::FloatTyID: 241 case Type::UIntTyID: 242 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 243 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 244 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 245 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 246 break; 247 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 248 goto Store4BytesLittleEndian; 249 case Type::DoubleTyID: 250 case Type::ULongTyID: 251 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 252 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 253 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 254 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 255 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 256 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 257 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 258 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 259 break; 260 default: 261 std::cout << "Cannot store value of type " << Ty << "!\n"; 262 } 263 } else { 264 switch (Ty->getPrimitiveID()) { 265 case Type::BoolTyID: 266 case Type::UByteTyID: 267 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 268 case Type::UShortTyID: 269 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 270 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 271 break; 272 Store4BytesBigEndian: 273 case Type::FloatTyID: 274 case Type::UIntTyID: 275 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 276 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 277 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 278 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 279 break; 280 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 281 goto Store4BytesBigEndian; 282 case Type::DoubleTyID: 283 case Type::ULongTyID: 284 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 285 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 286 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 287 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 288 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 289 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 290 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 291 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 292 break; 293 default: 294 std::cout << "Cannot store value of type " << Ty << "!\n"; 295 } 296 } 297 } 298 299 /// FIXME: document 300 /// 301 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 302 const Type *Ty) { 303 GenericValue Result; 304 if (getTargetData().isLittleEndian()) { 305 switch (Ty->getPrimitiveID()) { 306 case Type::BoolTyID: 307 case Type::UByteTyID: 308 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 309 case Type::UShortTyID: 310 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 311 ((unsigned)Ptr->Untyped[1] << 8); 312 break; 313 Load4BytesLittleEndian: 314 case Type::FloatTyID: 315 case Type::UIntTyID: 316 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 317 ((unsigned)Ptr->Untyped[1] << 8) | 318 ((unsigned)Ptr->Untyped[2] << 16) | 319 ((unsigned)Ptr->Untyped[3] << 24); 320 break; 321 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 322 goto Load4BytesLittleEndian; 323 case Type::DoubleTyID: 324 case Type::ULongTyID: 325 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 326 ((uint64_t)Ptr->Untyped[1] << 8) | 327 ((uint64_t)Ptr->Untyped[2] << 16) | 328 ((uint64_t)Ptr->Untyped[3] << 24) | 329 ((uint64_t)Ptr->Untyped[4] << 32) | 330 ((uint64_t)Ptr->Untyped[5] << 40) | 331 ((uint64_t)Ptr->Untyped[6] << 48) | 332 ((uint64_t)Ptr->Untyped[7] << 56); 333 break; 334 default: 335 std::cout << "Cannot load value of type " << *Ty << "!\n"; 336 abort(); 337 } 338 } else { 339 switch (Ty->getPrimitiveID()) { 340 case Type::BoolTyID: 341 case Type::UByteTyID: 342 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 343 case Type::UShortTyID: 344 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 345 ((unsigned)Ptr->Untyped[0] << 8); 346 break; 347 Load4BytesBigEndian: 348 case Type::FloatTyID: 349 case Type::UIntTyID: 350 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 351 ((unsigned)Ptr->Untyped[2] << 8) | 352 ((unsigned)Ptr->Untyped[1] << 16) | 353 ((unsigned)Ptr->Untyped[0] << 24); 354 break; 355 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 356 goto Load4BytesBigEndian; 357 case Type::DoubleTyID: 358 case Type::ULongTyID: 359 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 360 ((uint64_t)Ptr->Untyped[6] << 8) | 361 ((uint64_t)Ptr->Untyped[5] << 16) | 362 ((uint64_t)Ptr->Untyped[4] << 24) | 363 ((uint64_t)Ptr->Untyped[3] << 32) | 364 ((uint64_t)Ptr->Untyped[2] << 40) | 365 ((uint64_t)Ptr->Untyped[1] << 48) | 366 ((uint64_t)Ptr->Untyped[0] << 56); 367 break; 368 default: 369 std::cout << "Cannot load value of type " << *Ty << "!\n"; 370 abort(); 371 } 372 } 373 return Result; 374 } 375 376 // InitializeMemory - Recursive function to apply a Constant value into the 377 // specified memory location... 378 // 379 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 380 if (Init->getType()->isFirstClassType()) { 381 GenericValue Val = getConstantValue(Init); 382 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 383 return; 384 } 385 386 switch (Init->getType()->getPrimitiveID()) { 387 case Type::ArrayTyID: { 388 const ConstantArray *CPA = cast<ConstantArray>(Init); 389 const std::vector<Use> &Val = CPA->getValues(); 390 unsigned ElementSize = 391 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 392 for (unsigned i = 0; i < Val.size(); ++i) 393 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 394 return; 395 } 396 397 case Type::StructTyID: { 398 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 399 const StructLayout *SL = 400 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 401 const std::vector<Use> &Val = CPS->getValues(); 402 for (unsigned i = 0; i < Val.size(); ++i) 403 InitializeMemory(cast<Constant>(Val[i].get()), 404 (char*)Addr+SL->MemberOffsets[i]); 405 return; 406 } 407 408 default: 409 std::cerr << "Bad Type: " << Init->getType() << "\n"; 410 assert(0 && "Unknown constant type to initialize memory with!"); 411 } 412 } 413 414 /// EmitGlobals - Emit all of the global variables to memory, storing their 415 /// addresses into GlobalAddress. This must make sure to copy the contents of 416 /// their initializers into the memory. 417 /// 418 void ExecutionEngine::emitGlobals() { 419 const TargetData &TD = getTargetData(); 420 421 // Loop over all of the global variables in the program, allocating the memory 422 // to hold them. 423 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 424 I != E; ++I) 425 if (!I->isExternal()) { 426 // Get the type of the global... 427 const Type *Ty = I->getType()->getElementType(); 428 429 // Allocate some memory for it! 430 unsigned Size = TD.getTypeSize(Ty); 431 addGlobalMapping(I, new char[Size]); 432 433 DEBUG(std::cerr << "Global '" << I->getName() << "' -> " 434 << (void*)GlobalAddress[I] << "\n"); 435 } else { 436 // External variable reference. Try to use the dynamic loader to 437 // get a pointer to it. 438 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 439 GlobalAddress[I] = SymAddr; 440 else { 441 std::cerr << "Could not resolve external global address: " 442 << I->getName() << "\n"; 443 abort(); 444 } 445 } 446 447 // Now that all of the globals are set up in memory, loop through them all and 448 // initialize their contents. 449 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 450 I != E; ++I) 451 if (!I->isExternal()) 452 EmitGlobalVariable(I); 453 } 454 455 // EmitGlobalVariable - This method emits the specified global variable to the 456 // address specified in GlobalAddresses, or allocates new memory if it's not 457 // already in the map. 458 void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) { 459 void *&GA = GlobalAddress[GV]; 460 const Type *ElTy = GV->getType()->getElementType(); 461 if (GA == 0) { 462 // If it's not already specified, allocate memory for the global. 463 GA = new char[getTargetData().getTypeSize(ElTy)]; 464 } 465 466 InitializeMemory(GV->getInitializer(), GA); 467 NumInitBytes += getTargetData().getTypeSize(ElTy); 468 ++NumGlobals; 469 } 470