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