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/VM.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 } 34 35 ExecutionEngine::ExecutionEngine(ModuleProvider *P) : 36 CurMod(*P->getModule()), MP(P) { 37 assert(P && "ModuleProvider is null?"); 38 } 39 40 ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) { 41 assert(M && "Module is null?"); 42 } 43 44 ExecutionEngine::~ExecutionEngine() { 45 delete MP; 46 } 47 48 /// If possible, create a JIT, unless the caller specifically requests an 49 /// Interpreter or there's an error. If even an Interpreter cannot be created, 50 /// NULL is returned. 51 /// 52 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 53 bool ForceInterpreter) { 54 ExecutionEngine *EE = 0; 55 56 // Unless the interpreter was explicitly selected, make a JIT. 57 if (!ForceInterpreter) 58 EE = VM::create(MP); 59 60 // If we can't make a JIT, make an interpreter instead. 61 try { 62 if (EE == 0) 63 EE = Interpreter::create(MP->materializeModule()); 64 } catch (...) { 65 EE = 0; 66 } 67 return EE; 68 } 69 70 /// getPointerToGlobal - This returns the address of the specified global 71 /// value. This may involve code generation if it's a function. 72 /// 73 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 74 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 75 return getPointerToFunction(F); 76 77 assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?"); 78 return GlobalAddress[GV]; 79 } 80 81 /// FIXME: document 82 /// 83 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 84 GenericValue Result; 85 86 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 87 switch (CE->getOpcode()) { 88 case Instruction::GetElementPtr: { 89 Result = getConstantValue(CE->getOperand(0)); 90 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 91 uint64_t Offset = 92 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 93 94 Result.LongVal += Offset; 95 return Result; 96 } 97 case Instruction::Cast: { 98 // We only need to handle a few cases here. Almost all casts will 99 // automatically fold, just the ones involving pointers won't. 100 // 101 Constant *Op = CE->getOperand(0); 102 103 // Handle cast of pointer to pointer... 104 if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID()) 105 return getConstantValue(Op); 106 107 // Handle a cast of pointer to any integral type... 108 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 109 return getConstantValue(Op); 110 111 // Handle cast of long to pointer... 112 if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy || 113 Op->getType() == Type::ULongTy)) 114 return getConstantValue(Op); 115 break; 116 } 117 118 case Instruction::Add: 119 if (CE->getOperand(0)->getType() == Type::LongTy || 120 CE->getOperand(0)->getType() == Type::ULongTy) 121 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 122 getConstantValue(CE->getOperand(1)).LongVal; 123 else 124 break; 125 return Result; 126 127 default: 128 break; 129 } 130 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 131 abort(); 132 } 133 134 switch (C->getType()->getPrimitiveID()) { 135 #define GET_CONST_VAL(TY, CLASS) \ 136 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 137 GET_CONST_VAL(Bool , ConstantBool); 138 GET_CONST_VAL(UByte , ConstantUInt); 139 GET_CONST_VAL(SByte , ConstantSInt); 140 GET_CONST_VAL(UShort , ConstantUInt); 141 GET_CONST_VAL(Short , ConstantSInt); 142 GET_CONST_VAL(UInt , ConstantUInt); 143 GET_CONST_VAL(Int , ConstantSInt); 144 GET_CONST_VAL(ULong , ConstantUInt); 145 GET_CONST_VAL(Long , ConstantSInt); 146 GET_CONST_VAL(Float , ConstantFP); 147 GET_CONST_VAL(Double , ConstantFP); 148 #undef GET_CONST_VAL 149 case Type::PointerTyID: 150 if (isa<ConstantPointerNull>(C)) { 151 Result.PointerVal = 0; 152 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 153 if (Function *F = 154 const_cast<Function*>(dyn_cast<Function>(CPR->getValue()))) 155 Result = PTOGV(getPointerToFunctionOrStub(F)); 156 else 157 Result = PTOGV(getPointerToGlobal(CPR->getValue())); 158 159 } else { 160 assert(0 && "Unknown constant pointer type!"); 161 } 162 break; 163 default: 164 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 165 abort(); 166 } 167 return Result; 168 } 169 170 /// FIXME: document 171 /// 172 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 173 const Type *Ty) { 174 if (getTargetData().isLittleEndian()) { 175 switch (Ty->getPrimitiveID()) { 176 case Type::BoolTyID: 177 case Type::UByteTyID: 178 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 179 case Type::UShortTyID: 180 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 181 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 182 break; 183 Store4BytesLittleEndian: 184 case Type::FloatTyID: 185 case Type::UIntTyID: 186 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 187 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 188 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 189 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 190 break; 191 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 192 goto Store4BytesLittleEndian; 193 case Type::DoubleTyID: 194 case Type::ULongTyID: 195 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 196 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 197 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 198 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 199 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 200 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 201 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 202 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 203 break; 204 default: 205 std::cout << "Cannot store value of type " << Ty << "!\n"; 206 } 207 } else { 208 switch (Ty->getPrimitiveID()) { 209 case Type::BoolTyID: 210 case Type::UByteTyID: 211 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 212 case Type::UShortTyID: 213 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 214 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 215 break; 216 Store4BytesBigEndian: 217 case Type::FloatTyID: 218 case Type::UIntTyID: 219 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 220 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 221 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 222 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 223 break; 224 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 225 goto Store4BytesBigEndian; 226 case Type::DoubleTyID: 227 case Type::ULongTyID: 228 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 229 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 230 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 231 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 232 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 233 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 234 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 235 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 236 break; 237 default: 238 std::cout << "Cannot store value of type " << Ty << "!\n"; 239 } 240 } 241 } 242 243 /// FIXME: document 244 /// 245 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 246 const Type *Ty) { 247 GenericValue Result; 248 if (getTargetData().isLittleEndian()) { 249 switch (Ty->getPrimitiveID()) { 250 case Type::BoolTyID: 251 case Type::UByteTyID: 252 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 253 case Type::UShortTyID: 254 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 255 ((unsigned)Ptr->Untyped[1] << 8); 256 break; 257 Load4BytesLittleEndian: 258 case Type::FloatTyID: 259 case Type::UIntTyID: 260 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 261 ((unsigned)Ptr->Untyped[1] << 8) | 262 ((unsigned)Ptr->Untyped[2] << 16) | 263 ((unsigned)Ptr->Untyped[3] << 24); 264 break; 265 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 266 goto Load4BytesLittleEndian; 267 case Type::DoubleTyID: 268 case Type::ULongTyID: 269 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 270 ((uint64_t)Ptr->Untyped[1] << 8) | 271 ((uint64_t)Ptr->Untyped[2] << 16) | 272 ((uint64_t)Ptr->Untyped[3] << 24) | 273 ((uint64_t)Ptr->Untyped[4] << 32) | 274 ((uint64_t)Ptr->Untyped[5] << 40) | 275 ((uint64_t)Ptr->Untyped[6] << 48) | 276 ((uint64_t)Ptr->Untyped[7] << 56); 277 break; 278 default: 279 std::cout << "Cannot load value of type " << *Ty << "!\n"; 280 abort(); 281 } 282 } else { 283 switch (Ty->getPrimitiveID()) { 284 case Type::BoolTyID: 285 case Type::UByteTyID: 286 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 287 case Type::UShortTyID: 288 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 289 ((unsigned)Ptr->Untyped[0] << 8); 290 break; 291 Load4BytesBigEndian: 292 case Type::FloatTyID: 293 case Type::UIntTyID: 294 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 295 ((unsigned)Ptr->Untyped[2] << 8) | 296 ((unsigned)Ptr->Untyped[1] << 16) | 297 ((unsigned)Ptr->Untyped[0] << 24); 298 break; 299 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 300 goto Load4BytesBigEndian; 301 case Type::DoubleTyID: 302 case Type::ULongTyID: 303 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 304 ((uint64_t)Ptr->Untyped[6] << 8) | 305 ((uint64_t)Ptr->Untyped[5] << 16) | 306 ((uint64_t)Ptr->Untyped[4] << 24) | 307 ((uint64_t)Ptr->Untyped[3] << 32) | 308 ((uint64_t)Ptr->Untyped[2] << 40) | 309 ((uint64_t)Ptr->Untyped[1] << 48) | 310 ((uint64_t)Ptr->Untyped[0] << 56); 311 break; 312 default: 313 std::cout << "Cannot load value of type " << *Ty << "!\n"; 314 abort(); 315 } 316 } 317 return Result; 318 } 319 320 // InitializeMemory - Recursive function to apply a Constant value into the 321 // specified memory location... 322 // 323 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 324 if (Init->getType()->isFirstClassType()) { 325 GenericValue Val = getConstantValue(Init); 326 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 327 return; 328 } 329 330 switch (Init->getType()->getPrimitiveID()) { 331 case Type::ArrayTyID: { 332 const ConstantArray *CPA = cast<ConstantArray>(Init); 333 const std::vector<Use> &Val = CPA->getValues(); 334 unsigned ElementSize = 335 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 336 for (unsigned i = 0; i < Val.size(); ++i) 337 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 338 return; 339 } 340 341 case Type::StructTyID: { 342 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 343 const StructLayout *SL = 344 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 345 const std::vector<Use> &Val = CPS->getValues(); 346 for (unsigned i = 0; i < Val.size(); ++i) 347 InitializeMemory(cast<Constant>(Val[i].get()), 348 (char*)Addr+SL->MemberOffsets[i]); 349 return; 350 } 351 352 default: 353 std::cerr << "Bad Type: " << Init->getType() << "\n"; 354 assert(0 && "Unknown constant type to initialize memory with!"); 355 } 356 } 357 358 /// EmitGlobals - Emit all of the global variables to memory, storing their 359 /// addresses into GlobalAddress. This must make sure to copy the contents of 360 /// their initializers into the memory. 361 /// 362 void ExecutionEngine::emitGlobals() { 363 const TargetData &TD = getTargetData(); 364 365 // Loop over all of the global variables in the program, allocating the memory 366 // to hold them. 367 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 368 I != E; ++I) 369 if (!I->isExternal()) { 370 // Get the type of the global... 371 const Type *Ty = I->getType()->getElementType(); 372 373 // Allocate some memory for it! 374 unsigned Size = TD.getTypeSize(Ty); 375 GlobalAddress[I] = new char[Size]; 376 NumInitBytes += Size; 377 378 DEBUG(std::cerr << "Global '" << I->getName() << "' -> " 379 << (void*)GlobalAddress[I] << "\n"); 380 } else { 381 // External variable reference. Try to use the dynamic loader to 382 // get a pointer to it. 383 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 384 GlobalAddress[I] = SymAddr; 385 else { 386 std::cerr << "Could not resolve external global address: " 387 << I->getName() << "\n"; 388 abort(); 389 } 390 } 391 392 // Now that all of the globals are set up in memory, loop through them all and 393 // initialize their contents. 394 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 395 I != E; ++I) 396 if (!I->isExternal()) 397 InitializeMemory(I->getInitializer(), GlobalAddress[I]); 398 } 399