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 30 namespace llvm { 31 32 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized"); 33 34 ExecutionEngine::ExecutionEngine(ModuleProvider *P) : 35 CurMod(*P->getModule()), MP(P) { 36 assert(P && "ModuleProvider is null?"); 37 } 38 39 ExecutionEngine::ExecutionEngine(Module *M) : CurMod(*M), MP(0) { 40 assert(M && "Module is null?"); 41 } 42 43 ExecutionEngine::~ExecutionEngine() { 44 delete MP; 45 } 46 47 /// If possible, create a JIT, unless the caller specifically requests an 48 /// Interpreter or there's an error. If even an Interpreter cannot be created, 49 /// NULL is returned. 50 /// 51 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 52 bool ForceInterpreter) { 53 ExecutionEngine *EE = 0; 54 55 // Unless the interpreter was explicitly selected, make a JIT. 56 if (!ForceInterpreter) 57 EE = VM::create(MP); 58 59 // If we can't make a JIT, make an interpreter instead. 60 try { 61 if (EE == 0) 62 EE = Interpreter::create(MP->materializeModule()); 63 } catch (...) { 64 EE = 0; 65 } 66 return EE; 67 } 68 69 /// getPointerToGlobal - This returns the address of the specified global 70 /// value. This may involve code generation if it's a function. 71 /// 72 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 73 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 74 return getPointerToFunction(F); 75 76 assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?"); 77 return GlobalAddress[GV]; 78 } 79 80 /// FIXME: document 81 /// 82 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 83 GenericValue Result; 84 85 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 86 switch (CE->getOpcode()) { 87 case Instruction::GetElementPtr: { 88 Result = getConstantValue(CE->getOperand(0)); 89 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 90 uint64_t Offset = 91 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 92 93 Result.LongVal += Offset; 94 return Result; 95 } 96 case Instruction::Cast: { 97 // We only need to handle a few cases here. Almost all casts will 98 // automatically fold, just the ones involving pointers won't. 99 // 100 Constant *Op = CE->getOperand(0); 101 102 // Handle cast of pointer to pointer... 103 if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID()) 104 return getConstantValue(Op); 105 106 // Handle a cast of pointer to any integral type... 107 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 108 return getConstantValue(Op); 109 110 // Handle cast of long to pointer... 111 if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy || 112 Op->getType() == Type::ULongTy)) 113 return getConstantValue(Op); 114 break; 115 } 116 117 case Instruction::Add: 118 if (CE->getOperand(0)->getType() == Type::LongTy || 119 CE->getOperand(0)->getType() == Type::ULongTy) 120 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 121 getConstantValue(CE->getOperand(1)).LongVal; 122 else 123 break; 124 return Result; 125 126 default: 127 break; 128 } 129 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 130 abort(); 131 } 132 133 switch (C->getType()->getPrimitiveID()) { 134 #define GET_CONST_VAL(TY, CLASS) \ 135 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 136 GET_CONST_VAL(Bool , ConstantBool); 137 GET_CONST_VAL(UByte , ConstantUInt); 138 GET_CONST_VAL(SByte , ConstantSInt); 139 GET_CONST_VAL(UShort , ConstantUInt); 140 GET_CONST_VAL(Short , ConstantSInt); 141 GET_CONST_VAL(UInt , ConstantUInt); 142 GET_CONST_VAL(Int , ConstantSInt); 143 GET_CONST_VAL(ULong , ConstantUInt); 144 GET_CONST_VAL(Long , ConstantSInt); 145 GET_CONST_VAL(Float , ConstantFP); 146 GET_CONST_VAL(Double , ConstantFP); 147 #undef GET_CONST_VAL 148 case Type::PointerTyID: 149 if (isa<ConstantPointerNull>(C)) { 150 Result.PointerVal = 0; 151 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 152 Result = PTOGV(getPointerToGlobal(CPR->getValue())); 153 154 } else { 155 assert(0 && "Unknown constant pointer type!"); 156 } 157 break; 158 default: 159 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 160 abort(); 161 } 162 return Result; 163 } 164 165 /// FIXME: document 166 /// 167 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 168 const Type *Ty) { 169 if (getTargetData().isLittleEndian()) { 170 switch (Ty->getPrimitiveID()) { 171 case Type::BoolTyID: 172 case Type::UByteTyID: 173 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 174 case Type::UShortTyID: 175 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 176 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 177 break; 178 Store4BytesLittleEndian: 179 case Type::FloatTyID: 180 case Type::UIntTyID: 181 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 182 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 183 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 184 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 185 break; 186 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 187 goto Store4BytesLittleEndian; 188 case Type::DoubleTyID: 189 case Type::ULongTyID: 190 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 191 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 192 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 193 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 194 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 195 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 196 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 197 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 198 break; 199 default: 200 std::cout << "Cannot store value of type " << Ty << "!\n"; 201 } 202 } else { 203 switch (Ty->getPrimitiveID()) { 204 case Type::BoolTyID: 205 case Type::UByteTyID: 206 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 207 case Type::UShortTyID: 208 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 209 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 210 break; 211 Store4BytesBigEndian: 212 case Type::FloatTyID: 213 case Type::UIntTyID: 214 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 215 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 216 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 217 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 218 break; 219 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 220 goto Store4BytesBigEndian; 221 case Type::DoubleTyID: 222 case Type::ULongTyID: 223 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 224 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 225 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 226 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 227 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 228 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 229 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 230 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 231 break; 232 default: 233 std::cout << "Cannot store value of type " << Ty << "!\n"; 234 } 235 } 236 } 237 238 /// FIXME: document 239 /// 240 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 241 const Type *Ty) { 242 GenericValue Result; 243 if (getTargetData().isLittleEndian()) { 244 switch (Ty->getPrimitiveID()) { 245 case Type::BoolTyID: 246 case Type::UByteTyID: 247 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 248 case Type::UShortTyID: 249 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 250 ((unsigned)Ptr->Untyped[1] << 8); 251 break; 252 Load4BytesLittleEndian: 253 case Type::FloatTyID: 254 case Type::UIntTyID: 255 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 256 ((unsigned)Ptr->Untyped[1] << 8) | 257 ((unsigned)Ptr->Untyped[2] << 16) | 258 ((unsigned)Ptr->Untyped[3] << 24); 259 break; 260 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 261 goto Load4BytesLittleEndian; 262 case Type::DoubleTyID: 263 case Type::ULongTyID: 264 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 265 ((uint64_t)Ptr->Untyped[1] << 8) | 266 ((uint64_t)Ptr->Untyped[2] << 16) | 267 ((uint64_t)Ptr->Untyped[3] << 24) | 268 ((uint64_t)Ptr->Untyped[4] << 32) | 269 ((uint64_t)Ptr->Untyped[5] << 40) | 270 ((uint64_t)Ptr->Untyped[6] << 48) | 271 ((uint64_t)Ptr->Untyped[7] << 56); 272 break; 273 default: 274 std::cout << "Cannot load value of type " << *Ty << "!\n"; 275 abort(); 276 } 277 } else { 278 switch (Ty->getPrimitiveID()) { 279 case Type::BoolTyID: 280 case Type::UByteTyID: 281 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 282 case Type::UShortTyID: 283 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 284 ((unsigned)Ptr->Untyped[0] << 8); 285 break; 286 Load4BytesBigEndian: 287 case Type::FloatTyID: 288 case Type::UIntTyID: 289 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 290 ((unsigned)Ptr->Untyped[2] << 8) | 291 ((unsigned)Ptr->Untyped[1] << 16) | 292 ((unsigned)Ptr->Untyped[0] << 24); 293 break; 294 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 295 goto Load4BytesBigEndian; 296 case Type::DoubleTyID: 297 case Type::ULongTyID: 298 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 299 ((uint64_t)Ptr->Untyped[6] << 8) | 300 ((uint64_t)Ptr->Untyped[5] << 16) | 301 ((uint64_t)Ptr->Untyped[4] << 24) | 302 ((uint64_t)Ptr->Untyped[3] << 32) | 303 ((uint64_t)Ptr->Untyped[2] << 40) | 304 ((uint64_t)Ptr->Untyped[1] << 48) | 305 ((uint64_t)Ptr->Untyped[0] << 56); 306 break; 307 default: 308 std::cout << "Cannot load value of type " << *Ty << "!\n"; 309 abort(); 310 } 311 } 312 return Result; 313 } 314 315 // InitializeMemory - Recursive function to apply a Constant value into the 316 // specified memory location... 317 // 318 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 319 if (Init->getType()->isFirstClassType()) { 320 GenericValue Val = getConstantValue(Init); 321 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 322 return; 323 } 324 325 switch (Init->getType()->getPrimitiveID()) { 326 case Type::ArrayTyID: { 327 const ConstantArray *CPA = cast<ConstantArray>(Init); 328 const std::vector<Use> &Val = CPA->getValues(); 329 unsigned ElementSize = 330 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 331 for (unsigned i = 0; i < Val.size(); ++i) 332 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 333 return; 334 } 335 336 case Type::StructTyID: { 337 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 338 const StructLayout *SL = 339 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 340 const std::vector<Use> &Val = CPS->getValues(); 341 for (unsigned i = 0; i < Val.size(); ++i) 342 InitializeMemory(cast<Constant>(Val[i].get()), 343 (char*)Addr+SL->MemberOffsets[i]); 344 return; 345 } 346 347 default: 348 std::cerr << "Bad Type: " << Init->getType() << "\n"; 349 assert(0 && "Unknown constant type to initialize memory with!"); 350 } 351 } 352 353 /// EmitGlobals - Emit all of the global variables to memory, storing their 354 /// addresses into GlobalAddress. This must make sure to copy the contents of 355 /// their initializers into the memory. 356 /// 357 void ExecutionEngine::emitGlobals() { 358 const TargetData &TD = getTargetData(); 359 360 // Loop over all of the global variables in the program, allocating the memory 361 // to hold them. 362 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 363 I != E; ++I) 364 if (!I->isExternal()) { 365 // Get the type of the global... 366 const Type *Ty = I->getType()->getElementType(); 367 368 // Allocate some memory for it! 369 unsigned Size = TD.getTypeSize(Ty); 370 GlobalAddress[I] = new char[Size]; 371 NumInitBytes += Size; 372 373 DEBUG(std::cerr << "Global '" << I->getName() << "' -> " 374 << (void*)GlobalAddress[I] << "\n"); 375 } else { 376 // External variable reference. Try to use the dynamic loader to 377 // get a pointer to it. 378 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 379 GlobalAddress[I] = SymAddr; 380 else { 381 std::cerr << "Could not resolve external global address: " 382 << I->getName() << "\n"; 383 abort(); 384 } 385 } 386 387 // Now that all of the globals are set up in memory, loop through them all and 388 // initialize their contents. 389 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 390 I != E; ++I) 391 if (!I->isExternal()) 392 InitializeMemory(I->getInitializer(), GlobalAddress[I]); 393 } 394 395 } // End llvm namespace 396