1 //===-- ExecutionEngine.cpp - Common Implementation shared by EEs ---------===// 2 // 3 // This file defines the common interface used by the various execution engine 4 // subclasses. 5 // 6 //===----------------------------------------------------------------------===// 7 8 #define DEBUG_TYPE "jit" 9 #include "llvm/ExecutionEngine/ExecutionEngine.h" 10 #include "JIT/VM.h" 11 #include "Interpreter/Interpreter.h" 12 #include "llvm/DerivedTypes.h" 13 #include "llvm/Constants.h" 14 #include "llvm/Module.h" 15 #include "llvm/ExecutionEngine/GenericValue.h" 16 #include "llvm/Target/TargetData.h" 17 #include "Support/Debug.h" 18 #include "Support/Statistic.h" 19 #include "Support/DynamicLinker.h" 20 #include "Config/dlfcn.h" 21 22 Statistic<> NumInitBytes("lli", "Number of bytes of global vars initialized"); 23 24 ExecutionEngine::~ExecutionEngine() { 25 delete MP; 26 } 27 28 /// FIXME: document 29 /// 30 ExecutionEngine *ExecutionEngine::create(ModuleProvider *MP, 31 bool ForceInterpreter, 32 bool TraceMode) { 33 ExecutionEngine *EE = 0; 34 35 // If there is nothing that is forcing us to use the interpreter, make a JIT. 36 if (!ForceInterpreter && !TraceMode) 37 EE = VM::create(MP); 38 39 // If we can't make a JIT, make an interpreter instead. 40 if (EE == 0) 41 EE = Interpreter::create(MP->releaseModule(), TraceMode); 42 return EE; 43 } 44 45 /// getPointerToGlobal - This returns the address of the specified global 46 /// value. This may involve code generation if it's a function. 47 /// 48 void *ExecutionEngine::getPointerToGlobal(const GlobalValue *GV) { 49 if (Function *F = const_cast<Function*>(dyn_cast<Function>(GV))) 50 return getPointerToFunction(F); 51 52 assert(GlobalAddress[GV] && "Global hasn't had an address allocated yet?"); 53 return GlobalAddress[GV]; 54 } 55 56 /// FIXME: document 57 /// 58 GenericValue ExecutionEngine::getConstantValue(const Constant *C) { 59 GenericValue Result; 60 61 if (ConstantExpr *CE = const_cast<ConstantExpr*>(dyn_cast<ConstantExpr>(C))) { 62 switch (CE->getOpcode()) { 63 case Instruction::GetElementPtr: { 64 Result = getConstantValue(CE->getOperand(0)); 65 std::vector<Value*> Indexes(CE->op_begin()+1, CE->op_end()); 66 uint64_t Offset = 67 TD->getIndexedOffset(CE->getOperand(0)->getType(), Indexes); 68 69 Result.LongVal += Offset; 70 return Result; 71 } 72 case Instruction::Cast: { 73 // We only need to handle a few cases here. Almost all casts will 74 // automatically fold, just the ones involving pointers won't. 75 // 76 Constant *Op = CE->getOperand(0); 77 78 // Handle cast of pointer to pointer... 79 if (Op->getType()->getPrimitiveID() == C->getType()->getPrimitiveID()) 80 return getConstantValue(Op); 81 82 // Handle a cast of pointer to any integral type... 83 if (isa<PointerType>(Op->getType()) && C->getType()->isIntegral()) 84 return getConstantValue(Op); 85 86 // Handle cast of long to pointer... 87 if (isa<PointerType>(C->getType()) && (Op->getType() == Type::LongTy || 88 Op->getType() == Type::ULongTy)) 89 return getConstantValue(Op); 90 break; 91 } 92 93 case Instruction::Add: 94 if (CE->getOperand(0)->getType() == Type::LongTy || 95 CE->getOperand(0)->getType() == Type::ULongTy) 96 Result.LongVal = getConstantValue(CE->getOperand(0)).LongVal + 97 getConstantValue(CE->getOperand(1)).LongVal; 98 else 99 break; 100 return Result; 101 102 default: 103 break; 104 } 105 std::cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; 106 abort(); 107 } 108 109 switch (C->getType()->getPrimitiveID()) { 110 #define GET_CONST_VAL(TY, CLASS) \ 111 case Type::TY##TyID: Result.TY##Val = cast<CLASS>(C)->getValue(); break 112 GET_CONST_VAL(Bool , ConstantBool); 113 GET_CONST_VAL(UByte , ConstantUInt); 114 GET_CONST_VAL(SByte , ConstantSInt); 115 GET_CONST_VAL(UShort , ConstantUInt); 116 GET_CONST_VAL(Short , ConstantSInt); 117 GET_CONST_VAL(UInt , ConstantUInt); 118 GET_CONST_VAL(Int , ConstantSInt); 119 GET_CONST_VAL(ULong , ConstantUInt); 120 GET_CONST_VAL(Long , ConstantSInt); 121 GET_CONST_VAL(Float , ConstantFP); 122 GET_CONST_VAL(Double , ConstantFP); 123 #undef GET_CONST_VAL 124 case Type::PointerTyID: 125 if (isa<ConstantPointerNull>(C)) { 126 Result.PointerVal = 0; 127 } else if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)){ 128 Result = PTOGV(getPointerToGlobal(CPR->getValue())); 129 130 } else { 131 assert(0 && "Unknown constant pointer type!"); 132 } 133 break; 134 default: 135 std::cout << "ERROR: Constant unimp for type: " << C->getType() << "\n"; 136 abort(); 137 } 138 return Result; 139 } 140 141 /// FIXME: document 142 /// 143 void ExecutionEngine::StoreValueToMemory(GenericValue Val, GenericValue *Ptr, 144 const Type *Ty) { 145 if (getTargetData().isLittleEndian()) { 146 switch (Ty->getPrimitiveID()) { 147 case Type::BoolTyID: 148 case Type::UByteTyID: 149 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 150 case Type::UShortTyID: 151 case Type::ShortTyID: Ptr->Untyped[0] = Val.UShortVal & 255; 152 Ptr->Untyped[1] = (Val.UShortVal >> 8) & 255; 153 break; 154 Store4BytesLittleEndian: 155 case Type::FloatTyID: 156 case Type::UIntTyID: 157 case Type::IntTyID: Ptr->Untyped[0] = Val.UIntVal & 255; 158 Ptr->Untyped[1] = (Val.UIntVal >> 8) & 255; 159 Ptr->Untyped[2] = (Val.UIntVal >> 16) & 255; 160 Ptr->Untyped[3] = (Val.UIntVal >> 24) & 255; 161 break; 162 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 163 goto Store4BytesLittleEndian; 164 case Type::DoubleTyID: 165 case Type::ULongTyID: 166 case Type::LongTyID: Ptr->Untyped[0] = Val.ULongVal & 255; 167 Ptr->Untyped[1] = (Val.ULongVal >> 8) & 255; 168 Ptr->Untyped[2] = (Val.ULongVal >> 16) & 255; 169 Ptr->Untyped[3] = (Val.ULongVal >> 24) & 255; 170 Ptr->Untyped[4] = (Val.ULongVal >> 32) & 255; 171 Ptr->Untyped[5] = (Val.ULongVal >> 40) & 255; 172 Ptr->Untyped[6] = (Val.ULongVal >> 48) & 255; 173 Ptr->Untyped[7] = (Val.ULongVal >> 56) & 255; 174 break; 175 default: 176 std::cout << "Cannot store value of type " << Ty << "!\n"; 177 } 178 } else { 179 switch (Ty->getPrimitiveID()) { 180 case Type::BoolTyID: 181 case Type::UByteTyID: 182 case Type::SByteTyID: Ptr->Untyped[0] = Val.UByteVal; break; 183 case Type::UShortTyID: 184 case Type::ShortTyID: Ptr->Untyped[1] = Val.UShortVal & 255; 185 Ptr->Untyped[0] = (Val.UShortVal >> 8) & 255; 186 break; 187 Store4BytesBigEndian: 188 case Type::FloatTyID: 189 case Type::UIntTyID: 190 case Type::IntTyID: Ptr->Untyped[3] = Val.UIntVal & 255; 191 Ptr->Untyped[2] = (Val.UIntVal >> 8) & 255; 192 Ptr->Untyped[1] = (Val.UIntVal >> 16) & 255; 193 Ptr->Untyped[0] = (Val.UIntVal >> 24) & 255; 194 break; 195 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 196 goto Store4BytesBigEndian; 197 case Type::DoubleTyID: 198 case Type::ULongTyID: 199 case Type::LongTyID: Ptr->Untyped[7] = Val.ULongVal & 255; 200 Ptr->Untyped[6] = (Val.ULongVal >> 8) & 255; 201 Ptr->Untyped[5] = (Val.ULongVal >> 16) & 255; 202 Ptr->Untyped[4] = (Val.ULongVal >> 24) & 255; 203 Ptr->Untyped[3] = (Val.ULongVal >> 32) & 255; 204 Ptr->Untyped[2] = (Val.ULongVal >> 40) & 255; 205 Ptr->Untyped[1] = (Val.ULongVal >> 48) & 255; 206 Ptr->Untyped[0] = (Val.ULongVal >> 56) & 255; 207 break; 208 default: 209 std::cout << "Cannot store value of type " << Ty << "!\n"; 210 } 211 } 212 } 213 214 /// FIXME: document 215 /// 216 GenericValue ExecutionEngine::LoadValueFromMemory(GenericValue *Ptr, 217 const Type *Ty) { 218 GenericValue Result; 219 if (getTargetData().isLittleEndian()) { 220 switch (Ty->getPrimitiveID()) { 221 case Type::BoolTyID: 222 case Type::UByteTyID: 223 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 224 case Type::UShortTyID: 225 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[0] | 226 ((unsigned)Ptr->Untyped[1] << 8); 227 break; 228 Load4BytesLittleEndian: 229 case Type::FloatTyID: 230 case Type::UIntTyID: 231 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[0] | 232 ((unsigned)Ptr->Untyped[1] << 8) | 233 ((unsigned)Ptr->Untyped[2] << 16) | 234 ((unsigned)Ptr->Untyped[3] << 24); 235 break; 236 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 237 goto Load4BytesLittleEndian; 238 case Type::DoubleTyID: 239 case Type::ULongTyID: 240 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[0] | 241 ((uint64_t)Ptr->Untyped[1] << 8) | 242 ((uint64_t)Ptr->Untyped[2] << 16) | 243 ((uint64_t)Ptr->Untyped[3] << 24) | 244 ((uint64_t)Ptr->Untyped[4] << 32) | 245 ((uint64_t)Ptr->Untyped[5] << 40) | 246 ((uint64_t)Ptr->Untyped[6] << 48) | 247 ((uint64_t)Ptr->Untyped[7] << 56); 248 break; 249 default: 250 std::cout << "Cannot load value of type " << *Ty << "!\n"; 251 abort(); 252 } 253 } else { 254 switch (Ty->getPrimitiveID()) { 255 case Type::BoolTyID: 256 case Type::UByteTyID: 257 case Type::SByteTyID: Result.UByteVal = Ptr->Untyped[0]; break; 258 case Type::UShortTyID: 259 case Type::ShortTyID: Result.UShortVal = (unsigned)Ptr->Untyped[1] | 260 ((unsigned)Ptr->Untyped[0] << 8); 261 break; 262 Load4BytesBigEndian: 263 case Type::FloatTyID: 264 case Type::UIntTyID: 265 case Type::IntTyID: Result.UIntVal = (unsigned)Ptr->Untyped[3] | 266 ((unsigned)Ptr->Untyped[2] << 8) | 267 ((unsigned)Ptr->Untyped[1] << 16) | 268 ((unsigned)Ptr->Untyped[0] << 24); 269 break; 270 case Type::PointerTyID: if (getTargetData().getPointerSize() == 4) 271 goto Load4BytesBigEndian; 272 case Type::DoubleTyID: 273 case Type::ULongTyID: 274 case Type::LongTyID: Result.ULongVal = (uint64_t)Ptr->Untyped[7] | 275 ((uint64_t)Ptr->Untyped[6] << 8) | 276 ((uint64_t)Ptr->Untyped[5] << 16) | 277 ((uint64_t)Ptr->Untyped[4] << 24) | 278 ((uint64_t)Ptr->Untyped[3] << 32) | 279 ((uint64_t)Ptr->Untyped[2] << 40) | 280 ((uint64_t)Ptr->Untyped[1] << 48) | 281 ((uint64_t)Ptr->Untyped[0] << 56); 282 break; 283 default: 284 std::cout << "Cannot load value of type " << *Ty << "!\n"; 285 abort(); 286 } 287 } 288 return Result; 289 } 290 291 // InitializeMemory - Recursive function to apply a Constant value into the 292 // specified memory location... 293 // 294 void ExecutionEngine::InitializeMemory(const Constant *Init, void *Addr) { 295 if (Init->getType()->isFirstClassType()) { 296 GenericValue Val = getConstantValue(Init); 297 StoreValueToMemory(Val, (GenericValue*)Addr, Init->getType()); 298 return; 299 } 300 301 switch (Init->getType()->getPrimitiveID()) { 302 case Type::ArrayTyID: { 303 const ConstantArray *CPA = cast<ConstantArray>(Init); 304 const std::vector<Use> &Val = CPA->getValues(); 305 unsigned ElementSize = 306 getTargetData().getTypeSize(cast<ArrayType>(CPA->getType())->getElementType()); 307 for (unsigned i = 0; i < Val.size(); ++i) 308 InitializeMemory(cast<Constant>(Val[i].get()), (char*)Addr+i*ElementSize); 309 return; 310 } 311 312 case Type::StructTyID: { 313 const ConstantStruct *CPS = cast<ConstantStruct>(Init); 314 const StructLayout *SL = 315 getTargetData().getStructLayout(cast<StructType>(CPS->getType())); 316 const std::vector<Use> &Val = CPS->getValues(); 317 for (unsigned i = 0; i < Val.size(); ++i) 318 InitializeMemory(cast<Constant>(Val[i].get()), 319 (char*)Addr+SL->MemberOffsets[i]); 320 return; 321 } 322 323 default: 324 std::cerr << "Bad Type: " << Init->getType() << "\n"; 325 assert(0 && "Unknown constant type to initialize memory with!"); 326 } 327 } 328 329 /// EmitGlobals - Emit all of the global variables to memory, storing their 330 /// addresses into GlobalAddress. This must make sure to copy the contents of 331 /// their initializers into the memory. 332 /// 333 void ExecutionEngine::emitGlobals() { 334 const TargetData &TD = getTargetData(); 335 336 // Loop over all of the global variables in the program, allocating the memory 337 // to hold them. 338 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 339 I != E; ++I) 340 if (!I->isExternal()) { 341 // Get the type of the global... 342 const Type *Ty = I->getType()->getElementType(); 343 344 // Allocate some memory for it! 345 unsigned Size = TD.getTypeSize(Ty); 346 GlobalAddress[I] = new char[Size]; 347 NumInitBytes += Size; 348 349 DEBUG(std::cerr << "Global '" << I->getName() << "' -> " 350 << (void*)GlobalAddress[I] << "\n"); 351 } else { 352 // External variable reference. Try to use the dynamic loader to 353 // get a pointer to it. 354 if (void *SymAddr = GetAddressOfSymbol(I->getName().c_str())) 355 GlobalAddress[I] = SymAddr; 356 else { 357 std::cerr << "Could not resolve external global address: " 358 << I->getName() << "\n"; 359 abort(); 360 } 361 } 362 363 // Now that all of the globals are set up in memory, loop through them all and 364 // initialize their contents. 365 for (Module::giterator I = getModule().gbegin(), E = getModule().gend(); 366 I != E; ++I) 367 if (!I->isExternal()) 368 InitializeMemory(I->getInitializer(), GlobalAddress[I]); 369 } 370 371