ExecutionEngine.cpp revision f70c22b019494723d0e706f93d6542dfaa6e73a5
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" 29using namespace llvm; 30 31namespace { 32 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized"); 33 Statistic<> NumGlobals ("lli", "Number of global vars initialized"); 34} 35 36ExecutionEngine::ExecutionEngine(ModuleProvider *P) : 37 CurMod(*P->getModule()), MP(P) { 38 assert(P && "ModuleProvider is null?"); 39} 40 41ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) { 42 assert(M && "Module is null?"); 43} 44 45ExecutionEngine::~ExecutionEngine() { 46 delete MP; 47} 48 49/// getGlobalValueAtAddress - Return the LLVM global value object that starts 50/// at the specified address. 51/// 52const 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// 68static 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. 99int 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/// 122ExecutionEngine *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 (...) { 141 std::cerr << "Error reading the bytecode file!\n"; 142 } 143 } 144 145 if (EE == 0) delete IL; 146 return EE; 147} 148 149/// getPointerToGlobal - This returns the address of the specified global 150/// value. This may involve code generation if it's a function. 151/// 152void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 153 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 154 return getPointerToFunction(F); 155 156 assert(GlobalAddressMap[GV] && "Global hasn't had an address allocated yet?"); 157 return GlobalAddressMap[GV]; 158} 159 160/// FIXME: document 161/// 162GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 163 GenericValue Result; 164 165 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 166 switch (CE->getOpcode()) { 167 case Instruction::GetElementPtr: { 168 Result = getConstantValue(CE->getOperand(0)); 169 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 170 uint64_t Offset = 171 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 172 173 Result.LongVal += Offset; 174 return Result; 175 } 176 case Instruction::Cast: { 177 // We only need to handle a few cases here. Almost all casts will 178 // automatically fold, just the ones involving pointers won't. 179 // 180 Constant *Op = CE->getOperand(0); 181 GenericValue GV = getConstantValue(Op); 182 183 // Handle cast of pointer to pointer... 184 if (Op->getType()->getTypeID() == C->getType()->getTypeID()) 185 return GV; 186 187 // Handle a cast of pointer to any integral type... 188 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 189 return GV; 190 191 // Handle cast of integer to a pointer... 192 if (isa<PointerType>(C->getType()) && Op->getType()->isIntegral()) 193 switch (Op->getType()->getTypeID()) { 194 case Type::BoolTyID: return PTOGV((void*)(uintptr_t)GV.BoolVal); 195 case Type::SByteTyID: return PTOGV((void*)( intptr_t)GV.SByteVal); 196 case Type::UByteTyID: return PTOGV((void*)(uintptr_t)GV.UByteVal); 197 case Type::ShortTyID: return PTOGV((void*)( intptr_t)GV.ShortVal); 198 case Type::UShortTyID: return PTOGV((void*)(uintptr_t)GV.UShortVal); 199 case Type::IntTyID: return PTOGV((void*)( intptr_t)GV.IntVal); 200 case Type::UIntTyID: return PTOGV((void*)(uintptr_t)GV.UIntVal); 201 case Type::LongTyID: return PTOGV((void*)( intptr_t)GV.LongVal); 202 case Type::ULongTyID: return PTOGV((void*)(uintptr_t)GV.ULongVal); 203 default: assert(0 && "Unknown integral type!"); 204 } 205 break; 206 } 207 208 case Instruction::Add: 209 if (CE->getOperand(0)->getType() == Type::LongTy || 210 CE->getOperand(0)->getType() == Type::ULongTy) 211 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 212 getConstantValue(CE->getOperand(1)).LongVal; 213 else 214 break; 215 return Result; 216 217 default: 218 break; 219 } 220 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 221 abort(); 222 } 223 224 switch (C->getType()->getTypeID()) { 225#define GET_CONST_VAL(TY, CLASS) \ 226 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 227 GET_CONST_VAL(Bool , ConstantBool); 228 GET_CONST_VAL(UByte , ConstantUInt); 229 GET_CONST_VAL(SByte , ConstantSInt); 230 GET_CONST_VAL(UShort , ConstantUInt); 231 GET_CONST_VAL(Short , ConstantSInt); 232 GET_CONST_VAL(UInt , ConstantUInt); 233 GET_CONST_VAL(Int , ConstantSInt); 234 GET_CONST_VAL(ULong , ConstantUInt); 235 GET_CONST_VAL(Long , ConstantSInt); 236 GET_CONST_VAL(Float , ConstantFP); 237 GET_CONST_VAL(Double , ConstantFP); 238#undef GET_CONST_VAL 239 case Type::PointerTyID: 240 if (isa<ConstantPointerNull>(C)) { 241 Result.PointerVal = 0; 242 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 243 if (Function *F = 244 const_cast<Function*>(dyn_cast<Function>(CPR->getValue()))) 245 Result = PTOGV(getPointerToFunctionOrStub(F)); 246 else 247 Result = PTOGV(getOrEmitGlobalVariable( 248 cast<GlobalVariable>(CPR->getValue()))); 249 250 } else { 251 assert(0 && "Unknown constant pointer type!"); 252 } 253 break; 254 default: 255 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 256 abort(); 257 } 258 return Result; 259} 260 261/// FIXME: document 262/// 263void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 264 const Type *Ty) { 265 if (getTargetData().isLittleEndian()) { 266 switch (Ty->getTypeID()) { 267 case Type::BoolTyID: 268 case Type::UByteTyID: 269 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 270 case Type::UShortTyID: 271 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 272 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 273 break; 274 Store4BytesLittleEndian: 275 case Type::FloatTyID: 276 case Type::UIntTyID: 277 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 278 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 279 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 280 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 281 break; 282 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 283 goto Store4BytesLittleEndian; 284 case Type::DoubleTyID: 285 case Type::ULongTyID: 286 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 287 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 288 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 289 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 290 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 291 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 292 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 293 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 294 break; 295 default: 296 std::cout << "Cannot store value of type " << Ty << "!\n"; 297 } 298 } else { 299 switch (Ty->getTypeID()) { 300 case Type::BoolTyID: 301 case Type::UByteTyID: 302 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 303 case Type::UShortTyID: 304 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 305 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 306 break; 307 Store4BytesBigEndian: 308 case Type::FloatTyID: 309 case Type::UIntTyID: 310 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 311 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 312 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 313 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 314 break; 315 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 316 goto Store4BytesBigEndian; 317 case Type::DoubleTyID: 318 case Type::ULongTyID: 319 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 320 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 321 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 322 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 323 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 324 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 325 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 326 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 327 break; 328 default: 329 std::cout << "Cannot store value of type " << Ty << "!\n"; 330 } 331 } 332} 333 334/// FIXME: document 335/// 336GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 337 const Type *Ty) { 338 GenericValue Result; 339 if (getTargetData().isLittleEndian()) { 340 switch (Ty->getTypeID()) { 341 case Type::BoolTyID: 342 case Type::UByteTyID: 343 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 344 case Type::UShortTyID: 345 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 346 ((unsigned)Ptr->Untyped[1] << 8); 347 break; 348 Load4BytesLittleEndian: 349 case Type::FloatTyID: 350 case Type::UIntTyID: 351 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 352 ((unsigned)Ptr->Untyped[1] << 8) | 353 ((unsigned)Ptr->Untyped[2] << 16) | 354 ((unsigned)Ptr->Untyped[3] << 24); 355 break; 356 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 357 goto Load4BytesLittleEndian; 358 case Type::DoubleTyID: 359 case Type::ULongTyID: 360 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 361 ((uint64_t)Ptr->Untyped[1] << 8) | 362 ((uint64_t)Ptr->Untyped[2] << 16) | 363 ((uint64_t)Ptr->Untyped[3] << 24) | 364 ((uint64_t)Ptr->Untyped[4] << 32) | 365 ((uint64_t)Ptr->Untyped[5] << 40) | 366 ((uint64_t)Ptr->Untyped[6] << 48) | 367 ((uint64_t)Ptr->Untyped[7] << 56); 368 break; 369 default: 370 std::cout << "Cannot load value of type " << *Ty << "!\n"; 371 abort(); 372 } 373 } else { 374 switch (Ty->getTypeID()) { 375 case Type::BoolTyID: 376 case Type::UByteTyID: 377 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 378 case Type::UShortTyID: 379 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 380 ((unsigned)Ptr->Untyped[0] << 8); 381 break; 382 Load4BytesBigEndian: 383 case Type::FloatTyID: 384 case Type::UIntTyID: 385 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 386 ((unsigned)Ptr->Untyped[2] << 8) | 387 ((unsigned)Ptr->Untyped[1] << 16) | 388 ((unsigned)Ptr->Untyped[0] << 24); 389 break; 390 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 391 goto Load4BytesBigEndian; 392 case Type::DoubleTyID: 393 case Type::ULongTyID: 394 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 395 ((uint64_t)Ptr->Untyped[6] << 8) | 396 ((uint64_t)Ptr->Untyped[5] << 16) | 397 ((uint64_t)Ptr->Untyped[4] << 24) | 398 ((uint64_t)Ptr->Untyped[3] << 32) | 399 ((uint64_t)Ptr->Untyped[2] << 40) | 400 ((uint64_t)Ptr->Untyped[1] << 48) | 401 ((uint64_t)Ptr->Untyped[0] << 56); 402 break; 403 default: 404 std::cout << "Cannot load value of type " << *Ty << "!\n"; 405 abort(); 406 } 407 } 408 return Result; 409} 410 411// InitializeMemory - Recursive function to apply a Constant value into the 412// specified memory location... 413// 414void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 415 if (Init->getType()->isFirstClassType()) { 416 GenericValue Val = getConstantValue(Init); 417 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 418 return; 419 } else if (isa<ConstantAggregateZero>(Init)) { 420 unsigned Size = getTargetData().getTypeSize(Init->getType()); 421 memset(Addr, 0, Size); 422 return; 423 } 424 425 switch (Init->getType()->getTypeID()) { 426 case Type::ArrayTyID: { 427 const ConstantArray *CPA = cast<ConstantArray>(Init); 428 const std::vector<Use> &Val = CPA->getValues(); 429 unsigned ElementSize = 430 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 431 for (unsigned i = 0; i < Val.size(); ++i) 432 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 433 return; 434 } 435 436 case Type::StructTyID: { 437 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 438 const StructLayout *SL = 439 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 440 const std::vector<Use> &Val = CPS->getValues(); 441 for (unsigned i = 0; i < Val.size(); ++i) 442 InitializeMemory(cast<Constant>(Val[i].get()), 443 (char*)Addr+SL->MemberOffsets[i]); 444 return; 445 } 446 447 default: 448 std::cerr << "Bad Type: " << Init->getType() << "\n"; 449 assert(0 && "Unknown constant type to initialize memory with!"); 450 } 451} 452 453/// EmitGlobals - Emit all of the global variables to memory, storing their 454/// addresses into GlobalAddress. This must make sure to copy the contents of 455/// their initializers into the memory. 456/// 457void ExecutionEngine::emitGlobals() { 458 const TargetData &TD = getTargetData(); 459 460 // Loop over all of the global variables in the program, allocating the memory 461 // to hold them. 462 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 463 I != E; ++I) 464 if (!I->isExternal()) { 465 // Get the type of the global... 466 const Type *Ty = I->getType()->getElementType(); 467 468 // Allocate some memory for it! 469 unsigned Size = TD.getTypeSize(Ty); 470 addGlobalMapping(I, new char[Size]); 471 } else { 472 // External variable reference. Try to use the dynamic loader to 473 // get a pointer to it. 474 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 475 addGlobalMapping(I, SymAddr); 476 else { 477 std::cerr << "Could not resolve external global address: " 478 << I->getName() << "\n"; 479 abort(); 480 } 481 } 482 483 // Now that all of the globals are set up in memory, loop through them all and 484 // initialize their contents. 485 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 486 I != E; ++I) 487 if (!I->isExternal()) 488 EmitGlobalVariable(I); 489} 490 491// EmitGlobalVariable - This method emits the specified global variable to the 492// address specified in GlobalAddresses, or allocates new memory if it's not 493// already in the map. 494void ExecutionEngine::EmitGlobalVariable(const GlobalVariable *GV) { 495 void *GA = getPointerToGlobalIfAvailable(GV); 496 DEBUG(std::cerr << "Global '" << GV->getName() << "' -> " << GA << "\n"); 497 498 const Type *ElTy = GV->getType()->getElementType(); 499 if (GA == 0) { 500 // If it's not already specified, allocate memory for the global. 501 GA = new char[getTargetData().getTypeSize(ElTy)]; 502 addGlobalMapping(GV, GA); 503 } 504 505 InitializeMemory(GV->getInitializer(), GA); 506 NumInitBytes += getTargetData().getTypeSize(ElTy); 507 ++NumGlobals; 508} 509