LLVM API Documentation
00001 //===-- Constants.cpp - Implement Constant nodes --------------------------===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // This file implements the Constant* classes... 00011 // 00012 //===----------------------------------------------------------------------===// 00013 00014 #include "llvm/Constants.h" 00015 #include "ConstantFolding.h" 00016 #include "llvm/DerivedTypes.h" 00017 #include "llvm/GlobalValue.h" 00018 #include "llvm/Instructions.h" 00019 #include "llvm/SymbolTable.h" 00020 #include "llvm/Module.h" 00021 #include "llvm/ADT/StringExtras.h" 00022 #include "llvm/Support/MathExtras.h" 00023 #include "llvm/Support/Visibility.h" 00024 #include <algorithm> 00025 #include <iostream> 00026 using namespace llvm; 00027 00028 ConstantBool *ConstantBool::True = new ConstantBool(true); 00029 ConstantBool *ConstantBool::False = new ConstantBool(false); 00030 00031 00032 //===----------------------------------------------------------------------===// 00033 // Constant Class 00034 //===----------------------------------------------------------------------===// 00035 00036 void Constant::destroyConstantImpl() { 00037 // When a Constant is destroyed, there may be lingering 00038 // references to the constant by other constants in the constant pool. These 00039 // constants are implicitly dependent on the module that is being deleted, 00040 // but they don't know that. Because we only find out when the CPV is 00041 // deleted, we must now notify all of our users (that should only be 00042 // Constants) that they are, in fact, invalid now and should be deleted. 00043 // 00044 while (!use_empty()) { 00045 Value *V = use_back(); 00046 #ifndef NDEBUG // Only in -g mode... 00047 if (!isa<Constant>(V)) 00048 std::cerr << "While deleting: " << *this 00049 << "\n\nUse still stuck around after Def is destroyed: " 00050 << *V << "\n\n"; 00051 #endif 00052 assert(isa<Constant>(V) && "References remain to Constant being destroyed"); 00053 Constant *CV = cast<Constant>(V); 00054 CV->destroyConstant(); 00055 00056 // The constant should remove itself from our use list... 00057 assert((use_empty() || use_back() != V) && "Constant not removed!"); 00058 } 00059 00060 // Value has no outstanding references it is safe to delete it now... 00061 delete this; 00062 } 00063 00064 // Static constructor to create a '0' constant of arbitrary type... 00065 Constant *Constant::getNullValue(const Type *Ty) { 00066 switch (Ty->getTypeID()) { 00067 case Type::BoolTyID: { 00068 static Constant *NullBool = ConstantBool::get(false); 00069 return NullBool; 00070 } 00071 case Type::SByteTyID: { 00072 static Constant *NullSByte = ConstantSInt::get(Type::SByteTy, 0); 00073 return NullSByte; 00074 } 00075 case Type::UByteTyID: { 00076 static Constant *NullUByte = ConstantUInt::get(Type::UByteTy, 0); 00077 return NullUByte; 00078 } 00079 case Type::ShortTyID: { 00080 static Constant *NullShort = ConstantSInt::get(Type::ShortTy, 0); 00081 return NullShort; 00082 } 00083 case Type::UShortTyID: { 00084 static Constant *NullUShort = ConstantUInt::get(Type::UShortTy, 0); 00085 return NullUShort; 00086 } 00087 case Type::IntTyID: { 00088 static Constant *NullInt = ConstantSInt::get(Type::IntTy, 0); 00089 return NullInt; 00090 } 00091 case Type::UIntTyID: { 00092 static Constant *NullUInt = ConstantUInt::get(Type::UIntTy, 0); 00093 return NullUInt; 00094 } 00095 case Type::LongTyID: { 00096 static Constant *NullLong = ConstantSInt::get(Type::LongTy, 0); 00097 return NullLong; 00098 } 00099 case Type::ULongTyID: { 00100 static Constant *NullULong = ConstantUInt::get(Type::ULongTy, 0); 00101 return NullULong; 00102 } 00103 00104 case Type::FloatTyID: { 00105 static Constant *NullFloat = ConstantFP::get(Type::FloatTy, 0); 00106 return NullFloat; 00107 } 00108 case Type::DoubleTyID: { 00109 static Constant *NullDouble = ConstantFP::get(Type::DoubleTy, 0); 00110 return NullDouble; 00111 } 00112 00113 case Type::PointerTyID: 00114 return ConstantPointerNull::get(cast<PointerType>(Ty)); 00115 00116 case Type::StructTyID: 00117 case Type::ArrayTyID: 00118 case Type::PackedTyID: 00119 return ConstantAggregateZero::get(Ty); 00120 default: 00121 // Function, Label, or Opaque type? 00122 assert(!"Cannot create a null constant of that type!"); 00123 return 0; 00124 } 00125 } 00126 00127 // Static constructor to create the maximum constant of an integral type... 00128 ConstantIntegral *ConstantIntegral::getMaxValue(const Type *Ty) { 00129 switch (Ty->getTypeID()) { 00130 case Type::BoolTyID: return ConstantBool::True; 00131 case Type::SByteTyID: 00132 case Type::ShortTyID: 00133 case Type::IntTyID: 00134 case Type::LongTyID: { 00135 // Calculate 011111111111111... 00136 unsigned TypeBits = Ty->getPrimitiveSize()*8; 00137 int64_t Val = INT64_MAX; // All ones 00138 Val >>= 64-TypeBits; // Shift out unwanted 1 bits... 00139 return ConstantSInt::get(Ty, Val); 00140 } 00141 00142 case Type::UByteTyID: 00143 case Type::UShortTyID: 00144 case Type::UIntTyID: 00145 case Type::ULongTyID: return getAllOnesValue(Ty); 00146 00147 default: return 0; 00148 } 00149 } 00150 00151 // Static constructor to create the minimum constant for an integral type... 00152 ConstantIntegral *ConstantIntegral::getMinValue(const Type *Ty) { 00153 switch (Ty->getTypeID()) { 00154 case Type::BoolTyID: return ConstantBool::False; 00155 case Type::SByteTyID: 00156 case Type::ShortTyID: 00157 case Type::IntTyID: 00158 case Type::LongTyID: { 00159 // Calculate 1111111111000000000000 00160 unsigned TypeBits = Ty->getPrimitiveSize()*8; 00161 int64_t Val = -1; // All ones 00162 Val <<= TypeBits-1; // Shift over to the right spot 00163 return ConstantSInt::get(Ty, Val); 00164 } 00165 00166 case Type::UByteTyID: 00167 case Type::UShortTyID: 00168 case Type::UIntTyID: 00169 case Type::ULongTyID: return ConstantUInt::get(Ty, 0); 00170 00171 default: return 0; 00172 } 00173 } 00174 00175 // Static constructor to create an integral constant with all bits set 00176 ConstantIntegral *ConstantIntegral::getAllOnesValue(const Type *Ty) { 00177 switch (Ty->getTypeID()) { 00178 case Type::BoolTyID: return ConstantBool::True; 00179 case Type::SByteTyID: 00180 case Type::ShortTyID: 00181 case Type::IntTyID: 00182 case Type::LongTyID: return ConstantSInt::get(Ty, -1); 00183 00184 case Type::UByteTyID: 00185 case Type::UShortTyID: 00186 case Type::UIntTyID: 00187 case Type::ULongTyID: { 00188 // Calculate ~0 of the right type... 00189 unsigned TypeBits = Ty->getPrimitiveSize()*8; 00190 uint64_t Val = ~0ULL; // All ones 00191 Val >>= 64-TypeBits; // Shift out unwanted 1 bits... 00192 return ConstantUInt::get(Ty, Val); 00193 } 00194 default: return 0; 00195 } 00196 } 00197 00198 bool ConstantUInt::isAllOnesValue() const { 00199 unsigned TypeBits = getType()->getPrimitiveSize()*8; 00200 uint64_t Val = ~0ULL; // All ones 00201 Val >>= 64-TypeBits; // Shift out inappropriate bits 00202 return getValue() == Val; 00203 } 00204 00205 00206 //===----------------------------------------------------------------------===// 00207 // ConstantXXX Classes 00208 //===----------------------------------------------------------------------===// 00209 00210 //===----------------------------------------------------------------------===// 00211 // Normal Constructors 00212 00213 ConstantIntegral::ConstantIntegral(const Type *Ty, ValueTy VT, uint64_t V) 00214 : Constant(Ty, VT, 0, 0) { 00215 Val.Unsigned = V; 00216 } 00217 00218 ConstantBool::ConstantBool(bool V) 00219 : ConstantIntegral(Type::BoolTy, ConstantBoolVal, V) { 00220 } 00221 00222 ConstantInt::ConstantInt(const Type *Ty, ValueTy VT, uint64_t V) 00223 : ConstantIntegral(Ty, VT, V) { 00224 } 00225 00226 ConstantSInt::ConstantSInt(const Type *Ty, int64_t V) 00227 : ConstantInt(Ty, ConstantSIntVal, V) { 00228 assert(Ty->isInteger() && Ty->isSigned() && 00229 "Illegal type for signed integer constant!"); 00230 assert(isValueValidForType(Ty, V) && "Value too large for type!"); 00231 } 00232 00233 ConstantUInt::ConstantUInt(const Type *Ty, uint64_t V) 00234 : ConstantInt(Ty, ConstantUIntVal, V) { 00235 assert(Ty->isInteger() && Ty->isUnsigned() && 00236 "Illegal type for unsigned integer constant!"); 00237 assert(isValueValidForType(Ty, V) && "Value too large for type!"); 00238 } 00239 00240 ConstantFP::ConstantFP(const Type *Ty, double V) 00241 : Constant(Ty, ConstantFPVal, 0, 0) { 00242 assert(isValueValidForType(Ty, V) && "Value too large for type!"); 00243 Val = V; 00244 } 00245 00246 ConstantArray::ConstantArray(const ArrayType *T, 00247 const std::vector<Constant*> &V) 00248 : Constant(T, ConstantArrayVal, new Use[V.size()], V.size()) { 00249 assert(V.size() == T->getNumElements() && 00250 "Invalid initializer vector for constant array"); 00251 Use *OL = OperandList; 00252 for (std::vector<Constant*>::const_iterator I = V.begin(), E = V.end(); 00253 I != E; ++I, ++OL) { 00254 Constant *C = *I; 00255 assert((C->getType() == T->getElementType() || 00256 (T->isAbstract() && 00257 C->getType()->getTypeID() == T->getElementType()->getTypeID())) && 00258 "Initializer for array element doesn't match array element type!"); 00259 OL->init(C, this); 00260 } 00261 } 00262 00263 ConstantArray::~ConstantArray() { 00264 delete [] OperandList; 00265 } 00266 00267 ConstantStruct::ConstantStruct(const StructType *T, 00268 const std::vector<Constant*> &V) 00269 : Constant(T, ConstantStructVal, new Use[V.size()], V.size()) { 00270 assert(V.size() == T->getNumElements() && 00271 "Invalid initializer vector for constant structure"); 00272 Use *OL = OperandList; 00273 for (std::vector<Constant*>::const_iterator I = V.begin(), E = V.end(); 00274 I != E; ++I, ++OL) { 00275 Constant *C = *I; 00276 assert((C->getType() == T->getElementType(I-V.begin()) || 00277 ((T->getElementType(I-V.begin())->isAbstract() || 00278 C->getType()->isAbstract()) && 00279 T->getElementType(I-V.begin())->getTypeID() == 00280 C->getType()->getTypeID())) && 00281 "Initializer for struct element doesn't match struct element type!"); 00282 OL->init(C, this); 00283 } 00284 } 00285 00286 ConstantStruct::~ConstantStruct() { 00287 delete [] OperandList; 00288 } 00289 00290 00291 ConstantPacked::ConstantPacked(const PackedType *T, 00292 const std::vector<Constant*> &V) 00293 : Constant(T, ConstantPackedVal, new Use[V.size()], V.size()) { 00294 Use *OL = OperandList; 00295 for (std::vector<Constant*>::const_iterator I = V.begin(), E = V.end(); 00296 I != E; ++I, ++OL) { 00297 Constant *C = *I; 00298 assert((C->getType() == T->getElementType() || 00299 (T->isAbstract() && 00300 C->getType()->getTypeID() == T->getElementType()->getTypeID())) && 00301 "Initializer for packed element doesn't match packed element type!"); 00302 OL->init(C, this); 00303 } 00304 } 00305 00306 ConstantPacked::~ConstantPacked() { 00307 delete [] OperandList; 00308 } 00309 00310 /// UnaryConstantExpr - This class is private to Constants.cpp, and is used 00311 /// behind the scenes to implement unary constant exprs. 00312 namespace { 00313 class VISIBILITY_HIDDEN UnaryConstantExpr : public ConstantExpr { 00314 Use Op; 00315 public: 00316 UnaryConstantExpr(unsigned Opcode, Constant *C, const Type *Ty) 00317 : ConstantExpr(Ty, Opcode, &Op, 1), Op(C, this) {} 00318 }; 00319 } 00320 00321 static bool isSetCC(unsigned Opcode) { 00322 return Opcode == Instruction::SetEQ || Opcode == Instruction::SetNE || 00323 Opcode == Instruction::SetLT || Opcode == Instruction::SetGT || 00324 Opcode == Instruction::SetLE || Opcode == Instruction::SetGE; 00325 } 00326 00327 /// BinaryConstantExpr - This class is private to Constants.cpp, and is used 00328 /// behind the scenes to implement binary constant exprs. 00329 namespace { 00330 class VISIBILITY_HIDDEN BinaryConstantExpr : public ConstantExpr { 00331 Use Ops[2]; 00332 public: 00333 BinaryConstantExpr(unsigned Opcode, Constant *C1, Constant *C2) 00334 : ConstantExpr(isSetCC(Opcode) ? Type::BoolTy : C1->getType(), 00335 Opcode, Ops, 2) { 00336 Ops[0].init(C1, this); 00337 Ops[1].init(C2, this); 00338 } 00339 }; 00340 } 00341 00342 /// SelectConstantExpr - This class is private to Constants.cpp, and is used 00343 /// behind the scenes to implement select constant exprs. 00344 namespace { 00345 class VISIBILITY_HIDDEN SelectConstantExpr : public ConstantExpr { 00346 Use Ops[3]; 00347 public: 00348 SelectConstantExpr(Constant *C1, Constant *C2, Constant *C3) 00349 : ConstantExpr(C2->getType(), Instruction::Select, Ops, 3) { 00350 Ops[0].init(C1, this); 00351 Ops[1].init(C2, this); 00352 Ops[2].init(C3, this); 00353 } 00354 }; 00355 } 00356 00357 /// ExtractElementConstantExpr - This class is private to 00358 /// Constants.cpp, and is used behind the scenes to implement 00359 /// extractelement constant exprs. 00360 namespace { 00361 class VISIBILITY_HIDDEN ExtractElementConstantExpr : public ConstantExpr { 00362 Use Ops[2]; 00363 public: 00364 ExtractElementConstantExpr(Constant *C1, Constant *C2) 00365 : ConstantExpr(cast<PackedType>(C1->getType())->getElementType(), 00366 Instruction::ExtractElement, Ops, 2) { 00367 Ops[0].init(C1, this); 00368 Ops[1].init(C2, this); 00369 } 00370 }; 00371 } 00372 00373 /// InsertElementConstantExpr - This class is private to 00374 /// Constants.cpp, and is used behind the scenes to implement 00375 /// insertelement constant exprs. 00376 namespace { 00377 class VISIBILITY_HIDDEN InsertElementConstantExpr : public ConstantExpr { 00378 Use Ops[3]; 00379 public: 00380 InsertElementConstantExpr(Constant *C1, Constant *C2, Constant *C3) 00381 : ConstantExpr(C1->getType(), Instruction::InsertElement, 00382 Ops, 3) { 00383 Ops[0].init(C1, this); 00384 Ops[1].init(C2, this); 00385 Ops[2].init(C3, this); 00386 } 00387 }; 00388 } 00389 00390 /// ShuffleVectorConstantExpr - This class is private to 00391 /// Constants.cpp, and is used behind the scenes to implement 00392 /// shufflevector constant exprs. 00393 namespace { 00394 class VISIBILITY_HIDDEN ShuffleVectorConstantExpr : public ConstantExpr { 00395 Use Ops[3]; 00396 public: 00397 ShuffleVectorConstantExpr(Constant *C1, Constant *C2, Constant *C3) 00398 : ConstantExpr(C1->getType(), Instruction::ShuffleVector, 00399 Ops, 3) { 00400 Ops[0].init(C1, this); 00401 Ops[1].init(C2, this); 00402 Ops[2].init(C3, this); 00403 } 00404 }; 00405 } 00406 00407 /// GetElementPtrConstantExpr - This class is private to Constants.cpp, and is 00408 /// used behind the scenes to implement getelementpr constant exprs. 00409 namespace { 00410 struct VISIBILITY_HIDDEN GetElementPtrConstantExpr : public ConstantExpr { 00411 GetElementPtrConstantExpr(Constant *C, const std::vector<Constant*> &IdxList, 00412 const Type *DestTy) 00413 : ConstantExpr(DestTy, Instruction::GetElementPtr, 00414 new Use[IdxList.size()+1], IdxList.size()+1) { 00415 OperandList[0].init(C, this); 00416 for (unsigned i = 0, E = IdxList.size(); i != E; ++i) 00417 OperandList[i+1].init(IdxList[i], this); 00418 } 00419 ~GetElementPtrConstantExpr() { 00420 delete [] OperandList; 00421 } 00422 }; 00423 } 00424 00425 /// ConstantExpr::get* - Return some common constants without having to 00426 /// specify the full Instruction::OPCODE identifier. 00427 /// 00428 Constant *ConstantExpr::getNeg(Constant *C) { 00429 if (!C->getType()->isFloatingPoint()) 00430 return get(Instruction::Sub, getNullValue(C->getType()), C); 00431 else 00432 return get(Instruction::Sub, ConstantFP::get(C->getType(), -0.0), C); 00433 } 00434 Constant *ConstantExpr::getNot(Constant *C) { 00435 assert(isa<ConstantIntegral>(C) && "Cannot NOT a nonintegral type!"); 00436 return get(Instruction::Xor, C, 00437 ConstantIntegral::getAllOnesValue(C->getType())); 00438 } 00439 Constant *ConstantExpr::getAdd(Constant *C1, Constant *C2) { 00440 return get(Instruction::Add, C1, C2); 00441 } 00442 Constant *ConstantExpr::getSub(Constant *C1, Constant *C2) { 00443 return get(Instruction::Sub, C1, C2); 00444 } 00445 Constant *ConstantExpr::getMul(Constant *C1, Constant *C2) { 00446 return get(Instruction::Mul, C1, C2); 00447 } 00448 Constant *ConstantExpr::getDiv(Constant *C1, Constant *C2) { 00449 return get(Instruction::Div, C1, C2); 00450 } 00451 Constant *ConstantExpr::getRem(Constant *C1, Constant *C2) { 00452 return get(Instruction::Rem, C1, C2); 00453 } 00454 Constant *ConstantExpr::getAnd(Constant *C1, Constant *C2) { 00455 return get(Instruction::And, C1, C2); 00456 } 00457 Constant *ConstantExpr::getOr(Constant *C1, Constant *C2) { 00458 return get(Instruction::Or, C1, C2); 00459 } 00460 Constant *ConstantExpr::getXor(Constant *C1, Constant *C2) { 00461 return get(Instruction::Xor, C1, C2); 00462 } 00463 Constant *ConstantExpr::getSetEQ(Constant *C1, Constant *C2) { 00464 return get(Instruction::SetEQ, C1, C2); 00465 } 00466 Constant *ConstantExpr::getSetNE(Constant *C1, Constant *C2) { 00467 return get(Instruction::SetNE, C1, C2); 00468 } 00469 Constant *ConstantExpr::getSetLT(Constant *C1, Constant *C2) { 00470 return get(Instruction::SetLT, C1, C2); 00471 } 00472 Constant *ConstantExpr::getSetGT(Constant *C1, Constant *C2) { 00473 return get(Instruction::SetGT, C1, C2); 00474 } 00475 Constant *ConstantExpr::getSetLE(Constant *C1, Constant *C2) { 00476 return get(Instruction::SetLE, C1, C2); 00477 } 00478 Constant *ConstantExpr::getSetGE(Constant *C1, Constant *C2) { 00479 return get(Instruction::SetGE, C1, C2); 00480 } 00481 Constant *ConstantExpr::getShl(Constant *C1, Constant *C2) { 00482 return get(Instruction::Shl, C1, C2); 00483 } 00484 Constant *ConstantExpr::getShr(Constant *C1, Constant *C2) { 00485 return get(Instruction::Shr, C1, C2); 00486 } 00487 00488 Constant *ConstantExpr::getUShr(Constant *C1, Constant *C2) { 00489 if (C1->getType()->isUnsigned()) return getShr(C1, C2); 00490 return getCast(getShr(getCast(C1, 00491 C1->getType()->getUnsignedVersion()), C2), C1->getType()); 00492 } 00493 00494 Constant *ConstantExpr::getSShr(Constant *C1, Constant *C2) { 00495 if (C1->getType()->isSigned()) return getShr(C1, C2); 00496 return getCast(getShr(getCast(C1, 00497 C1->getType()->getSignedVersion()), C2), C1->getType()); 00498 } 00499 00500 /// getWithOperandReplaced - Return a constant expression identical to this 00501 /// one, but with the specified operand set to the specified value. 00502 Constant *ConstantExpr::getWithOperandReplaced(unsigned OpNo, 00503 Constant *Op) const { 00504 assert(OpNo < getNumOperands() && "Operand num is out of range!"); 00505 assert(Op->getType() == getOperand(OpNo)->getType() && 00506 "Replacing operand with value of different type!"); 00507 if (getOperand(OpNo) == Op) 00508 return const_cast<ConstantExpr*>(this); 00509 00510 Constant *Op0, *Op1, *Op2; 00511 switch (getOpcode()) { 00512 case Instruction::Cast: 00513 return ConstantExpr::getCast(Op, getType()); 00514 case Instruction::Select: 00515 Op0 = (OpNo == 0) ? Op : getOperand(0); 00516 Op1 = (OpNo == 1) ? Op : getOperand(1); 00517 Op2 = (OpNo == 2) ? Op : getOperand(2); 00518 return ConstantExpr::getSelect(Op0, Op1, Op2); 00519 case Instruction::InsertElement: 00520 Op0 = (OpNo == 0) ? Op : getOperand(0); 00521 Op1 = (OpNo == 1) ? Op : getOperand(1); 00522 Op2 = (OpNo == 2) ? Op : getOperand(2); 00523 return ConstantExpr::getInsertElement(Op0, Op1, Op2); 00524 case Instruction::ExtractElement: 00525 Op0 = (OpNo == 0) ? Op : getOperand(0); 00526 Op1 = (OpNo == 1) ? Op : getOperand(1); 00527 return ConstantExpr::getExtractElement(Op0, Op1); 00528 case Instruction::ShuffleVector: 00529 Op0 = (OpNo == 0) ? Op : getOperand(0); 00530 Op1 = (OpNo == 1) ? Op : getOperand(1); 00531 Op2 = (OpNo == 2) ? Op : getOperand(2); 00532 return ConstantExpr::getShuffleVector(Op0, Op1, Op2); 00533 case Instruction::GetElementPtr: { 00534 std::vector<Constant*> Ops; 00535 for (unsigned i = 1, e = getNumOperands(); i != e; ++i) 00536 Ops.push_back(getOperand(i)); 00537 if (OpNo == 0) 00538 return ConstantExpr::getGetElementPtr(Op, Ops); 00539 Ops[OpNo-1] = Op; 00540 return ConstantExpr::getGetElementPtr(getOperand(0), Ops); 00541 } 00542 default: 00543 assert(getNumOperands() == 2 && "Must be binary operator?"); 00544 Op0 = (OpNo == 0) ? Op : getOperand(0); 00545 Op1 = (OpNo == 1) ? Op : getOperand(1); 00546 return ConstantExpr::get(getOpcode(), Op0, Op1); 00547 } 00548 } 00549 00550 /// getWithOperands - This returns the current constant expression with the 00551 /// operands replaced with the specified values. The specified operands must 00552 /// match count and type with the existing ones. 00553 Constant *ConstantExpr:: 00554 getWithOperands(const std::vector<Constant*> &Ops) const { 00555 assert(Ops.size() == getNumOperands() && "Operand count mismatch!"); 00556 bool AnyChange = false; 00557 for (unsigned i = 0, e = Ops.size(); i != e; ++i) { 00558 assert(Ops[i]->getType() == getOperand(i)->getType() && 00559 "Operand type mismatch!"); 00560 AnyChange |= Ops[i] != getOperand(i); 00561 } 00562 if (!AnyChange) // No operands changed, return self. 00563 return const_cast<ConstantExpr*>(this); 00564 00565 switch (getOpcode()) { 00566 case Instruction::Cast: 00567 return ConstantExpr::getCast(Ops[0], getType()); 00568 case Instruction::Select: 00569 return ConstantExpr::getSelect(Ops[0], Ops[1], Ops[2]); 00570 case Instruction::InsertElement: 00571 return ConstantExpr::getInsertElement(Ops[0], Ops[1], Ops[2]); 00572 case Instruction::ExtractElement: 00573 return ConstantExpr::getExtractElement(Ops[0], Ops[1]); 00574 case Instruction::ShuffleVector: 00575 return ConstantExpr::getShuffleVector(Ops[0], Ops[1], Ops[2]); 00576 case Instruction::GetElementPtr: { 00577 std::vector<Constant*> ActualOps(Ops.begin()+1, Ops.end()); 00578 return ConstantExpr::getGetElementPtr(Ops[0], ActualOps); 00579 } 00580 default: 00581 assert(getNumOperands() == 2 && "Must be binary operator?"); 00582 return ConstantExpr::get(getOpcode(), Ops[0], Ops[1]); 00583 } 00584 } 00585 00586 00587 //===----------------------------------------------------------------------===// 00588 // isValueValidForType implementations 00589 00590 bool ConstantSInt::isValueValidForType(const Type *Ty, int64_t Val) { 00591 switch (Ty->getTypeID()) { 00592 default: 00593 return false; // These can't be represented as integers!!! 00594 // Signed types... 00595 case Type::SByteTyID: 00596 return (Val <= INT8_MAX && Val >= INT8_MIN); 00597 case Type::ShortTyID: 00598 return (Val <= INT16_MAX && Val >= INT16_MIN); 00599 case Type::IntTyID: 00600 return (Val <= int(INT32_MAX) && Val >= int(INT32_MIN)); 00601 case Type::LongTyID: 00602 return true; // This is the largest type... 00603 } 00604 } 00605 00606 bool ConstantUInt::isValueValidForType(const Type *Ty, uint64_t Val) { 00607 switch (Ty->getTypeID()) { 00608 default: 00609 return false; // These can't be represented as integers!!! 00610 00611 // Unsigned types... 00612 case Type::UByteTyID: 00613 return (Val <= UINT8_MAX); 00614 case Type::UShortTyID: 00615 return (Val <= UINT16_MAX); 00616 case Type::UIntTyID: 00617 return (Val <= UINT32_MAX); 00618 case Type::ULongTyID: 00619 return true; // This is the largest type... 00620 } 00621 } 00622 00623 bool ConstantFP::isValueValidForType(const Type *Ty, double Val) { 00624 switch (Ty->getTypeID()) { 00625 default: 00626 return false; // These can't be represented as floating point! 00627 00628 // TODO: Figure out how to test if a double can be cast to a float! 00629 case Type::FloatTyID: 00630 case Type::DoubleTyID: 00631 return true; // This is the largest type... 00632 } 00633 } 00634 00635 //===----------------------------------------------------------------------===// 00636 // Factory Function Implementation 00637 00638 // ConstantCreator - A class that is used to create constants by 00639 // ValueMap*. This class should be partially specialized if there is 00640 // something strange that needs to be done to interface to the ctor for the 00641 // constant. 00642 // 00643 namespace llvm { 00644 template<class ConstantClass, class TypeClass, class ValType> 00645 struct VISIBILITY_HIDDEN ConstantCreator { 00646 static ConstantClass *create(const TypeClass *Ty, const ValType &V) { 00647 return new ConstantClass(Ty, V); 00648 } 00649 }; 00650 00651 template<class ConstantClass, class TypeClass> 00652 struct VISIBILITY_HIDDEN ConvertConstantType { 00653 static void convert(ConstantClass *OldC, const TypeClass *NewTy) { 00654 assert(0 && "This type cannot be converted!\n"); 00655 abort(); 00656 } 00657 }; 00658 00659 template<class ValType, class TypeClass, class ConstantClass, 00660 bool HasLargeKey = false /*true for arrays and structs*/ > 00661 class VISIBILITY_HIDDEN ValueMap : public AbstractTypeUser { 00662 public: 00663 typedef std::pair<const Type*, ValType> MapKey; 00664 typedef std::map<MapKey, Constant *> MapTy; 00665 typedef std::map<Constant*, typename MapTy::iterator> InverseMapTy; 00666 typedef std::map<const Type*, typename MapTy::iterator> AbstractTypeMapTy; 00667 private: 00668 /// Map - This is the main map from the element descriptor to the Constants. 00669 /// This is the primary way we avoid creating two of the same shape 00670 /// constant. 00671 MapTy Map; 00672 00673 /// InverseMap - If "HasLargeKey" is true, this contains an inverse mapping 00674 /// from the constants to their element in Map. This is important for 00675 /// removal of constants from the array, which would otherwise have to scan 00676 /// through the map with very large keys. 00677 InverseMapTy InverseMap; 00678 00679 /// AbstractTypeMap - Map for abstract type constants. 00680 /// 00681 AbstractTypeMapTy AbstractTypeMap; 00682 00683 friend void Constant::clearAllValueMaps(); 00684 private: 00685 void clear(std::vector<Constant *> &Constants) { 00686 for(typename MapTy::iterator I = Map.begin(); I != Map.end(); ++I) 00687 Constants.push_back(I->second); 00688 Map.clear(); 00689 AbstractTypeMap.clear(); 00690 InverseMap.clear(); 00691 } 00692 00693 public: 00694 typename MapTy::iterator map_end() { return Map.end(); } 00695 00696 /// InsertOrGetItem - Return an iterator for the specified element. 00697 /// If the element exists in the map, the returned iterator points to the 00698 /// entry and Exists=true. If not, the iterator points to the newly 00699 /// inserted entry and returns Exists=false. Newly inserted entries have 00700 /// I->second == 0, and should be filled in. 00701 typename MapTy::iterator InsertOrGetItem(std::pair<MapKey, Constant *> 00702 &InsertVal, 00703 bool &Exists) { 00704 std::pair<typename MapTy::iterator, bool> IP = Map.insert(InsertVal); 00705 Exists = !IP.second; 00706 return IP.first; 00707 } 00708 00709 private: 00710 typename MapTy::iterator FindExistingElement(ConstantClass *CP) { 00711 if (HasLargeKey) { 00712 typename InverseMapTy::iterator IMI = InverseMap.find(CP); 00713 assert(IMI != InverseMap.end() && IMI->second != Map.end() && 00714 IMI->second->second == CP && 00715 "InverseMap corrupt!"); 00716 return IMI->second; 00717 } 00718 00719 typename MapTy::iterator I = 00720 Map.find(MapKey((TypeClass*)CP->getRawType(), getValType(CP))); 00721 if (I == Map.end() || I->second != CP) { 00722 // FIXME: This should not use a linear scan. If this gets to be a 00723 // performance problem, someone should look at this. 00724 for (I = Map.begin(); I != Map.end() && I->second != CP; ++I) 00725 /* empty */; 00726 } 00727 return I; 00728 } 00729 public: 00730 00731 /// getOrCreate - Return the specified constant from the map, creating it if 00732 /// necessary. 00733 ConstantClass *getOrCreate(const TypeClass *Ty, const ValType &V) { 00734 MapKey Lookup(Ty, V); 00735 typename MapTy::iterator I = Map.lower_bound(Lookup); 00736 if (I != Map.end() && I->first == Lookup) 00737 return static_cast<ConstantClass *>(I->second); // Is it in the map? 00738 00739 // If no preexisting value, create one now... 00740 ConstantClass *Result = 00741 ConstantCreator<ConstantClass,TypeClass,ValType>::create(Ty, V); 00742 00743 /// FIXME: why does this assert fail when loading 176.gcc? 00744 //assert(Result->getType() == Ty && "Type specified is not correct!"); 00745 I = Map.insert(I, std::make_pair(MapKey(Ty, V), Result)); 00746 00747 if (HasLargeKey) // Remember the reverse mapping if needed. 00748 InverseMap.insert(std::make_pair(Result, I)); 00749 00750 // If the type of the constant is abstract, make sure that an entry exists 00751 // for it in the AbstractTypeMap. 00752 if (Ty->isAbstract()) { 00753 typename AbstractTypeMapTy::iterator TI = 00754 AbstractTypeMap.lower_bound(Ty); 00755 00756 if (TI == AbstractTypeMap.end() || TI->first != Ty) { 00757 // Add ourselves to the ATU list of the type. 00758 cast<DerivedType>(Ty)->addAbstractTypeUser(this); 00759 00760 AbstractTypeMap.insert(TI, std::make_pair(Ty, I)); 00761 } 00762 } 00763 return Result; 00764 } 00765 00766 void remove(ConstantClass *CP) { 00767 typename MapTy::iterator I = FindExistingElement(CP); 00768 assert(I != Map.end() && "Constant not found in constant table!"); 00769 assert(I->second == CP && "Didn't find correct element?"); 00770 00771 if (HasLargeKey) // Remember the reverse mapping if needed. 00772 InverseMap.erase(CP); 00773 00774 // Now that we found the entry, make sure this isn't the entry that 00775 // the AbstractTypeMap points to. 00776 const TypeClass *Ty = static_cast<const TypeClass *>(I->first.first); 00777 if (Ty->isAbstract()) { 00778 assert(AbstractTypeMap.count(Ty) && 00779 "Abstract type not in AbstractTypeMap?"); 00780 typename MapTy::iterator &ATMEntryIt = AbstractTypeMap[Ty]; 00781 if (ATMEntryIt == I) { 00782 // Yes, we are removing the representative entry for this type. 00783 // See if there are any other entries of the same type. 00784 typename MapTy::iterator TmpIt = ATMEntryIt; 00785 00786 // First check the entry before this one... 00787 if (TmpIt != Map.begin()) { 00788 --TmpIt; 00789 if (TmpIt->first.first != Ty) // Not the same type, move back... 00790 ++TmpIt; 00791 } 00792 00793 // If we didn't find the same type, try to move forward... 00794 if (TmpIt == ATMEntryIt) { 00795 ++TmpIt; 00796 if (TmpIt == Map.end() || TmpIt->first.first != Ty) 00797 --TmpIt; // No entry afterwards with the same type 00798 } 00799 00800 // If there is another entry in the map of the same abstract type, 00801 // update the AbstractTypeMap entry now. 00802 if (TmpIt != ATMEntryIt) { 00803 ATMEntryIt = TmpIt; 00804 } else { 00805 // Otherwise, we are removing the last instance of this type 00806 // from the table. Remove from the ATM, and from user list. 00807 cast<DerivedType>(Ty)->removeAbstractTypeUser(this); 00808 AbstractTypeMap.erase(Ty); 00809 } 00810 } 00811 } 00812 00813 Map.erase(I); 00814 } 00815 00816 00817 /// MoveConstantToNewSlot - If we are about to change C to be the element 00818 /// specified by I, update our internal data structures to reflect this 00819 /// fact. 00820 void MoveConstantToNewSlot(ConstantClass *C, typename MapTy::iterator I) { 00821 // First, remove the old location of the specified constant in the map. 00822 typename MapTy::iterator OldI = FindExistingElement(C); 00823 assert(OldI != Map.end() && "Constant not found in constant table!"); 00824 assert(OldI->second == C && "Didn't find correct element?"); 00825 00826 // If this constant is the representative element for its abstract type, 00827 // update the AbstractTypeMap so that the representative element is I. 00828 if (C->getType()->isAbstract()) { 00829 typename AbstractTypeMapTy::iterator ATI = 00830 AbstractTypeMap.find(C->getType()); 00831 assert(ATI != AbstractTypeMap.end() && 00832 "Abstract type not in AbstractTypeMap?"); 00833 if (ATI->second == OldI) 00834 ATI->second = I; 00835 } 00836 00837 // Remove the old entry from the map. 00838 Map.erase(OldI); 00839 00840 // Update the inverse map so that we know that this constant is now 00841 // located at descriptor I. 00842 if (HasLargeKey) { 00843 assert(I->second == C && "Bad inversemap entry!"); 00844 InverseMap[C] = I; 00845 } 00846 } 00847 00848 void refineAbstractType(const DerivedType *OldTy, const Type *NewTy) { 00849 typename AbstractTypeMapTy::iterator I = 00850 AbstractTypeMap.find(cast<Type>(OldTy)); 00851 00852 assert(I != AbstractTypeMap.end() && 00853 "Abstract type not in AbstractTypeMap?"); 00854 00855 // Convert a constant at a time until the last one is gone. The last one 00856 // leaving will remove() itself, causing the AbstractTypeMapEntry to be 00857 // eliminated eventually. 00858 do { 00859 ConvertConstantType<ConstantClass, 00860 TypeClass>::convert( 00861 static_cast<ConstantClass *>(I->second->second), 00862 cast<TypeClass>(NewTy)); 00863 00864 I = AbstractTypeMap.find(cast<Type>(OldTy)); 00865 } while (I != AbstractTypeMap.end()); 00866 } 00867 00868 // If the type became concrete without being refined to any other existing 00869 // type, we just remove ourselves from the ATU list. 00870 void typeBecameConcrete(const DerivedType *AbsTy) { 00871 AbsTy->removeAbstractTypeUser(this); 00872 } 00873 00874 void dump() const { 00875 std::cerr << "Constant.cpp: ValueMap\n"; 00876 } 00877 }; 00878 } 00879 00880 //---- ConstantUInt::get() and ConstantSInt::get() implementations... 00881 // 00882 static ValueMap< int64_t, Type, ConstantSInt> SIntConstants; 00883 static ValueMap<uint64_t, Type, ConstantUInt> UIntConstants; 00884 00885 ConstantSInt *ConstantSInt::get(const Type *Ty, int64_t V) { 00886 return SIntConstants.getOrCreate(Ty, V); 00887 } 00888 00889 ConstantUInt *ConstantUInt::get(const Type *Ty, uint64_t V) { 00890 return UIntConstants.getOrCreate(Ty, V); 00891 } 00892 00893 ConstantInt *ConstantInt::get(const Type *Ty, unsigned char V) { 00894 assert(V <= 127 && "Can only be used with very small positive constants!"); 00895 if (Ty->isSigned()) return ConstantSInt::get(Ty, V); 00896 return ConstantUInt::get(Ty, V); 00897 } 00898 00899 //---- ConstantFP::get() implementation... 00900 // 00901 namespace llvm { 00902 template<> 00903 struct ConstantCreator<ConstantFP, Type, uint64_t> { 00904 static ConstantFP *create(const Type *Ty, uint64_t V) { 00905 assert(Ty == Type::DoubleTy); 00906 return new ConstantFP(Ty, BitsToDouble(V)); 00907 } 00908 }; 00909 template<> 00910 struct ConstantCreator<ConstantFP, Type, uint32_t> { 00911 static ConstantFP *create(const Type *Ty, uint32_t V) { 00912 assert(Ty == Type::FloatTy); 00913 return new ConstantFP(Ty, BitsToFloat(V)); 00914 } 00915 }; 00916 } 00917 00918 static ValueMap<uint64_t, Type, ConstantFP> DoubleConstants; 00919 static ValueMap<uint32_t, Type, ConstantFP> FloatConstants; 00920 00921 bool ConstantFP::isNullValue() const { 00922 return DoubleToBits(Val) == 0; 00923 } 00924 00925 bool ConstantFP::isExactlyValue(double V) const { 00926 return DoubleToBits(V) == DoubleToBits(Val); 00927 } 00928 00929 00930 ConstantFP *ConstantFP::get(const Type *Ty, double V) { 00931 if (Ty == Type::FloatTy) { 00932 // Force the value through memory to normalize it. 00933 return FloatConstants.getOrCreate(Ty, FloatToBits(V)); 00934 } else { 00935 assert(Ty == Type::DoubleTy); 00936 return DoubleConstants.getOrCreate(Ty, DoubleToBits(V)); 00937 } 00938 } 00939 00940 //---- ConstantAggregateZero::get() implementation... 00941 // 00942 namespace llvm { 00943 // ConstantAggregateZero does not take extra "value" argument... 00944 template<class ValType> 00945 struct ConstantCreator<ConstantAggregateZero, Type, ValType> { 00946 static ConstantAggregateZero *create(const Type *Ty, const ValType &V){ 00947 return new ConstantAggregateZero(Ty); 00948 } 00949 }; 00950 00951 template<> 00952 struct ConvertConstantType<ConstantAggregateZero, Type> { 00953 static void convert(ConstantAggregateZero *OldC, const Type *NewTy) { 00954 // Make everyone now use a constant of the new type... 00955 Constant *New = ConstantAggregateZero::get(NewTy); 00956 assert(New != OldC && "Didn't replace constant??"); 00957 OldC->uncheckedReplaceAllUsesWith(New); 00958 OldC->destroyConstant(); // This constant is now dead, destroy it. 00959 } 00960 }; 00961 } 00962 00963 static ValueMap<char, Type, ConstantAggregateZero> AggZeroConstants; 00964 00965 static char getValType(ConstantAggregateZero *CPZ) { return 0; } 00966 00967 Constant *ConstantAggregateZero::get(const Type *Ty) { 00968 assert((isa<StructType>(Ty) || isa<ArrayType>(Ty) || isa<PackedType>(Ty)) && 00969 "Cannot create an aggregate zero of non-aggregate type!"); 00970 return AggZeroConstants.getOrCreate(Ty, 0); 00971 } 00972 00973 // destroyConstant - Remove the constant from the constant table... 00974 // 00975 void ConstantAggregateZero::destroyConstant() { 00976 AggZeroConstants.remove(this); 00977 destroyConstantImpl(); 00978 } 00979 00980 //---- ConstantArray::get() implementation... 00981 // 00982 namespace llvm { 00983 template<> 00984 struct ConvertConstantType<ConstantArray, ArrayType> { 00985 static void convert(ConstantArray *OldC, const ArrayType *NewTy) { 00986 // Make everyone now use a constant of the new type... 00987 std::vector<Constant*> C; 00988 for (unsigned i = 0, e = OldC->getNumOperands(); i != e; ++i) 00989 C.push_back(cast<Constant>(OldC->getOperand(i))); 00990 Constant *New = ConstantArray::get(NewTy, C); 00991 assert(New != OldC && "Didn't replace constant??"); 00992 OldC->uncheckedReplaceAllUsesWith(New); 00993 OldC->destroyConstant(); // This constant is now dead, destroy it. 00994 } 00995 }; 00996 } 00997 00998 static std::vector<Constant*> getValType(ConstantArray *CA) { 00999 std::vector<Constant*> Elements; 01000 Elements.reserve(CA->getNumOperands()); 01001 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 01002 Elements.push_back(cast<Constant>(CA->getOperand(i))); 01003 return Elements; 01004 } 01005 01006 typedef ValueMap<std::vector<Constant*>, ArrayType, 01007 ConstantArray, true /*largekey*/> ArrayConstantsTy; 01008 static ArrayConstantsTy ArrayConstants; 01009 01010 Constant *ConstantArray::get(const ArrayType *Ty, 01011 const std::vector<Constant*> &V) { 01012 // If this is an all-zero array, return a ConstantAggregateZero object 01013 if (!V.empty()) { 01014 Constant *C = V[0]; 01015 if (!C->isNullValue()) 01016 return ArrayConstants.getOrCreate(Ty, V); 01017 for (unsigned i = 1, e = V.size(); i != e; ++i) 01018 if (V[i] != C) 01019 return ArrayConstants.getOrCreate(Ty, V); 01020 } 01021 return ConstantAggregateZero::get(Ty); 01022 } 01023 01024 // destroyConstant - Remove the constant from the constant table... 01025 // 01026 void ConstantArray::destroyConstant() { 01027 ArrayConstants.remove(this); 01028 destroyConstantImpl(); 01029 } 01030 01031 /// ConstantArray::get(const string&) - Return an array that is initialized to 01032 /// contain the specified string. If length is zero then a null terminator is 01033 /// added to the specified string so that it may be used in a natural way. 01034 /// Otherwise, the length parameter specifies how much of the string to use 01035 /// and it won't be null terminated. 01036 /// 01037 Constant *ConstantArray::get(const std::string &Str, bool AddNull) { 01038 std::vector<Constant*> ElementVals; 01039 for (unsigned i = 0; i < Str.length(); ++i) 01040 ElementVals.push_back(ConstantSInt::get(Type::SByteTy, Str[i])); 01041 01042 // Add a null terminator to the string... 01043 if (AddNull) { 01044 ElementVals.push_back(ConstantSInt::get(Type::SByteTy, 0)); 01045 } 01046 01047 ArrayType *ATy = ArrayType::get(Type::SByteTy, ElementVals.size()); 01048 return ConstantArray::get(ATy, ElementVals); 01049 } 01050 01051 /// isString - This method returns true if the array is an array of sbyte or 01052 /// ubyte, and if the elements of the array are all ConstantInt's. 01053 bool ConstantArray::isString() const { 01054 // Check the element type for sbyte or ubyte... 01055 if (getType()->getElementType() != Type::UByteTy && 01056 getType()->getElementType() != Type::SByteTy) 01057 return false; 01058 // Check the elements to make sure they are all integers, not constant 01059 // expressions. 01060 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) 01061 if (!isa<ConstantInt>(getOperand(i))) 01062 return false; 01063 return true; 01064 } 01065 01066 // getAsString - If the sub-element type of this array is either sbyte or ubyte, 01067 // then this method converts the array to an std::string and returns it. 01068 // Otherwise, it asserts out. 01069 // 01070 std::string ConstantArray::getAsString() const { 01071 assert(isString() && "Not a string!"); 01072 std::string Result; 01073 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) 01074 Result += (char)cast<ConstantInt>(getOperand(i))->getRawValue(); 01075 return Result; 01076 } 01077 01078 01079 //---- ConstantStruct::get() implementation... 01080 // 01081 01082 namespace llvm { 01083 template<> 01084 struct ConvertConstantType<ConstantStruct, StructType> { 01085 static void convert(ConstantStruct *OldC, const StructType *NewTy) { 01086 // Make everyone now use a constant of the new type... 01087 std::vector<Constant*> C; 01088 for (unsigned i = 0, e = OldC->getNumOperands(); i != e; ++i) 01089 C.push_back(cast<Constant>(OldC->getOperand(i))); 01090 Constant *New = ConstantStruct::get(NewTy, C); 01091 assert(New != OldC && "Didn't replace constant??"); 01092 01093 OldC->uncheckedReplaceAllUsesWith(New); 01094 OldC->destroyConstant(); // This constant is now dead, destroy it. 01095 } 01096 }; 01097 } 01098 01099 typedef ValueMap<std::vector<Constant*>, StructType, 01100 ConstantStruct, true /*largekey*/> StructConstantsTy; 01101 static StructConstantsTy StructConstants; 01102 01103 static std::vector<Constant*> getValType(ConstantStruct *CS) { 01104 std::vector<Constant*> Elements; 01105 Elements.reserve(CS->getNumOperands()); 01106 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) 01107 Elements.push_back(cast<Constant>(CS->getOperand(i))); 01108 return Elements; 01109 } 01110 01111 Constant *ConstantStruct::get(const StructType *Ty, 01112 const std::vector<Constant*> &V) { 01113 // Create a ConstantAggregateZero value if all elements are zeros... 01114 for (unsigned i = 0, e = V.size(); i != e; ++i) 01115 if (!V[i]->isNullValue()) 01116 return StructConstants.getOrCreate(Ty, V); 01117 01118 return ConstantAggregateZero::get(Ty); 01119 } 01120 01121 Constant *ConstantStruct::get(const std::vector<Constant*> &V) { 01122 std::vector<const Type*> StructEls; 01123 StructEls.reserve(V.size()); 01124 for (unsigned i = 0, e = V.size(); i != e; ++i) 01125 StructEls.push_back(V[i]->getType()); 01126 return get(StructType::get(StructEls), V); 01127 } 01128 01129 // destroyConstant - Remove the constant from the constant table... 01130 // 01131 void ConstantStruct::destroyConstant() { 01132 StructConstants.remove(this); 01133 destroyConstantImpl(); 01134 } 01135 01136 //---- ConstantPacked::get() implementation... 01137 // 01138 namespace llvm { 01139 template<> 01140 struct ConvertConstantType<ConstantPacked, PackedType> { 01141 static void convert(ConstantPacked *OldC, const PackedType *NewTy) { 01142 // Make everyone now use a constant of the new type... 01143 std::vector<Constant*> C; 01144 for (unsigned i = 0, e = OldC->getNumOperands(); i != e; ++i) 01145 C.push_back(cast<Constant>(OldC->getOperand(i))); 01146 Constant *New = ConstantPacked::get(NewTy, C); 01147 assert(New != OldC && "Didn't replace constant??"); 01148 OldC->uncheckedReplaceAllUsesWith(New); 01149 OldC->destroyConstant(); // This constant is now dead, destroy it. 01150 } 01151 }; 01152 } 01153 01154 static std::vector<Constant*> getValType(ConstantPacked *CP) { 01155 std::vector<Constant*> Elements; 01156 Elements.reserve(CP->getNumOperands()); 01157 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) 01158 Elements.push_back(CP->getOperand(i)); 01159 return Elements; 01160 } 01161 01162 static ValueMap<std::vector<Constant*>, PackedType, 01163 ConstantPacked> PackedConstants; 01164 01165 Constant *ConstantPacked::get(const PackedType *Ty, 01166 const std::vector<Constant*> &V) { 01167 // If this is an all-zero packed, return a ConstantAggregateZero object 01168 if (!V.empty()) { 01169 Constant *C = V[0]; 01170 if (!C->isNullValue()) 01171 return PackedConstants.getOrCreate(Ty, V); 01172 for (unsigned i = 1, e = V.size(); i != e; ++i) 01173 if (V[i] != C) 01174 return PackedConstants.getOrCreate(Ty, V); 01175 } 01176 return ConstantAggregateZero::get(Ty); 01177 } 01178 01179 Constant *ConstantPacked::get(const std::vector<Constant*> &V) { 01180 assert(!V.empty() && "Cannot infer type if V is empty"); 01181 return get(PackedType::get(V.front()->getType(),V.size()), V); 01182 } 01183 01184 // destroyConstant - Remove the constant from the constant table... 01185 // 01186 void ConstantPacked::destroyConstant() { 01187 PackedConstants.remove(this); 01188 destroyConstantImpl(); 01189 } 01190 01191 //---- ConstantPointerNull::get() implementation... 01192 // 01193 01194 namespace llvm { 01195 // ConstantPointerNull does not take extra "value" argument... 01196 template<class ValType> 01197 struct ConstantCreator<ConstantPointerNull, PointerType, ValType> { 01198 static ConstantPointerNull *create(const PointerType *Ty, const ValType &V){ 01199 return new ConstantPointerNull(Ty); 01200 } 01201 }; 01202 01203 template<> 01204 struct ConvertConstantType<ConstantPointerNull, PointerType> { 01205 static void convert(ConstantPointerNull *OldC, const PointerType *NewTy) { 01206 // Make everyone now use a constant of the new type... 01207 Constant *New = ConstantPointerNull::get(NewTy); 01208 assert(New != OldC && "Didn't replace constant??"); 01209 OldC->uncheckedReplaceAllUsesWith(New); 01210 OldC->destroyConstant(); // This constant is now dead, destroy it. 01211 } 01212 }; 01213 } 01214 01215 static ValueMap<char, PointerType, ConstantPointerNull> NullPtrConstants; 01216 01217 static char getValType(ConstantPointerNull *) { 01218 return 0; 01219 } 01220 01221 01222 ConstantPointerNull *ConstantPointerNull::get(const PointerType *Ty) { 01223 return NullPtrConstants.getOrCreate(Ty, 0); 01224 } 01225 01226 // destroyConstant - Remove the constant from the constant table... 01227 // 01228 void ConstantPointerNull::destroyConstant() { 01229 NullPtrConstants.remove(this); 01230 destroyConstantImpl(); 01231 } 01232 01233 01234 //---- UndefValue::get() implementation... 01235 // 01236 01237 namespace llvm { 01238 // UndefValue does not take extra "value" argument... 01239 template<class ValType> 01240 struct ConstantCreator<UndefValue, Type, ValType> { 01241 static UndefValue *create(const Type *Ty, const ValType &V) { 01242 return new UndefValue(Ty); 01243 } 01244 }; 01245 01246 template<> 01247 struct ConvertConstantType<UndefValue, Type> { 01248 static void convert(UndefValue *OldC, const Type *NewTy) { 01249 // Make everyone now use a constant of the new type. 01250 Constant *New = UndefValue::get(NewTy); 01251 assert(New != OldC && "Didn't replace constant??"); 01252 OldC->uncheckedReplaceAllUsesWith(New); 01253 OldC->destroyConstant(); // This constant is now dead, destroy it. 01254 } 01255 }; 01256 } 01257 01258 static ValueMap<char, Type, UndefValue> UndefValueConstants; 01259 01260 static char getValType(UndefValue *) { 01261 return 0; 01262 } 01263 01264 01265 UndefValue *UndefValue::get(const Type *Ty) { 01266 return UndefValueConstants.getOrCreate(Ty, 0); 01267 } 01268 01269 // destroyConstant - Remove the constant from the constant table. 01270 // 01271 void UndefValue::destroyConstant() { 01272 UndefValueConstants.remove(this); 01273 destroyConstantImpl(); 01274 } 01275 01276 01277 01278 01279 //---- ConstantExpr::get() implementations... 01280 // 01281 typedef std::pair<unsigned, std::vector<Constant*> > ExprMapKeyType; 01282 01283 namespace llvm { 01284 template<> 01285 struct ConstantCreator<ConstantExpr, Type, ExprMapKeyType> { 01286 static ConstantExpr *create(const Type *Ty, const ExprMapKeyType &V) { 01287 if (V.first == Instruction::Cast) 01288 return new UnaryConstantExpr(Instruction::Cast, V.second[0], Ty); 01289 if ((V.first >= Instruction::BinaryOpsBegin && 01290 V.first < Instruction::BinaryOpsEnd) || 01291 V.first == Instruction::Shl || V.first == Instruction::Shr) 01292 return new BinaryConstantExpr(V.first, V.second[0], V.second[1]); 01293 if (V.first == Instruction::Select) 01294 return new SelectConstantExpr(V.second[0], V.second[1], V.second[2]); 01295 if (V.first == Instruction::ExtractElement) 01296 return new ExtractElementConstantExpr(V.second[0], V.second[1]); 01297 if (V.first == Instruction::InsertElement) 01298 return new InsertElementConstantExpr(V.second[0], V.second[1], 01299 V.second[2]); 01300 if (V.first == Instruction::ShuffleVector) 01301 return new ShuffleVectorConstantExpr(V.second[0], V.second[1], 01302 V.second[2]); 01303 01304 assert(V.first == Instruction::GetElementPtr && "Invalid ConstantExpr!"); 01305 01306 std::vector<Constant*> IdxList(V.second.begin()+1, V.second.end()); 01307 return new GetElementPtrConstantExpr(V.second[0], IdxList, Ty); 01308 } 01309 }; 01310 01311 template<> 01312 struct ConvertConstantType<ConstantExpr, Type> { 01313 static void convert(ConstantExpr *OldC, const Type *NewTy) { 01314 Constant *New; 01315 switch (OldC->getOpcode()) { 01316 case Instruction::Cast: 01317 New = ConstantExpr::getCast(OldC->getOperand(0), NewTy); 01318 break; 01319 case Instruction::Select: 01320 New = ConstantExpr::getSelectTy(NewTy, OldC->getOperand(0), 01321 OldC->getOperand(1), 01322 OldC->getOperand(2)); 01323 break; 01324 case Instruction::Shl: 01325 case Instruction::Shr: 01326 New = ConstantExpr::getShiftTy(NewTy, OldC->getOpcode(), 01327 OldC->getOperand(0), OldC->getOperand(1)); 01328 break; 01329 default: 01330 assert(OldC->getOpcode() >= Instruction::BinaryOpsBegin && 01331 OldC->getOpcode() < Instruction::BinaryOpsEnd); 01332 New = ConstantExpr::getTy(NewTy, OldC->getOpcode(), OldC->getOperand(0), 01333 OldC->getOperand(1)); 01334 break; 01335 case Instruction::GetElementPtr: 01336 // Make everyone now use a constant of the new type... 01337 std::vector<Value*> Idx(OldC->op_begin()+1, OldC->op_end()); 01338 New = ConstantExpr::getGetElementPtrTy(NewTy, OldC->getOperand(0), Idx); 01339 break; 01340 } 01341 01342 assert(New != OldC && "Didn't replace constant??"); 01343 OldC->uncheckedReplaceAllUsesWith(New); 01344 OldC->destroyConstant(); // This constant is now dead, destroy it. 01345 } 01346 }; 01347 } // end namespace llvm 01348 01349 01350 static ExprMapKeyType getValType(ConstantExpr *CE) { 01351 std::vector<Constant*> Operands; 01352 Operands.reserve(CE->getNumOperands()); 01353 for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) 01354 Operands.push_back(cast<Constant>(CE->getOperand(i))); 01355 return ExprMapKeyType(CE->getOpcode(), Operands); 01356 } 01357 01358 static ValueMap<ExprMapKeyType, Type, ConstantExpr> ExprConstants; 01359 01360 Constant *ConstantExpr::getCast(Constant *C, const Type *Ty) { 01361 assert(Ty->isFirstClassType() && "Cannot cast to an aggregate type!"); 01362 01363 if (Constant *FC = ConstantFoldCastInstruction(C, Ty)) 01364 return FC; // Fold a few common cases... 01365 01366 // Look up the constant in the table first to ensure uniqueness 01367 std::vector<Constant*> argVec(1, C); 01368 ExprMapKeyType Key = std::make_pair(Instruction::Cast, argVec); 01369 return ExprConstants.getOrCreate(Ty, Key); 01370 } 01371 01372 Constant *ConstantExpr::getSignExtend(Constant *C, const Type *Ty) { 01373 assert(C->getType()->isIntegral() && Ty->isIntegral() && 01374 C->getType()->getPrimitiveSize() <= Ty->getPrimitiveSize() && 01375 "This is an illegal sign extension!"); 01376 if (C->getType() != Type::BoolTy) { 01377 C = ConstantExpr::getCast(C, C->getType()->getSignedVersion()); 01378 return ConstantExpr::getCast(C, Ty); 01379 } else { 01380 if (C == ConstantBool::True) 01381 return ConstantIntegral::getAllOnesValue(Ty); 01382 else 01383 return ConstantIntegral::getNullValue(Ty); 01384 } 01385 } 01386 01387 Constant *ConstantExpr::getZeroExtend(Constant *C, const Type *Ty) { 01388 assert(C->getType()->isIntegral() && Ty->isIntegral() && 01389 C->getType()->getPrimitiveSize() <= Ty->getPrimitiveSize() && 01390 "This is an illegal zero extension!"); 01391 if (C->getType() != Type::BoolTy) 01392 C = ConstantExpr::getCast(C, C->getType()->getUnsignedVersion()); 01393 return ConstantExpr::getCast(C, Ty); 01394 } 01395 01396 Constant *ConstantExpr::getSizeOf(const Type *Ty) { 01397 // sizeof is implemented as: (ulong) gep (Ty*)null, 1 01398 return getCast( 01399 getGetElementPtr(getNullValue(PointerType::get(Ty)), 01400 std::vector<Constant*>(1, ConstantInt::get(Type::UIntTy, 1))), 01401 Type::ULongTy); 01402 } 01403 01404 Constant *ConstantExpr::getPtrPtrFromArrayPtr(Constant *C) { 01405 // pointer from array is implemented as: getelementptr arr ptr, 0, 0 01406 static std::vector<Constant*> Indices(2, ConstantUInt::get(Type::UIntTy, 0)); 01407 01408 return ConstantExpr::getGetElementPtr(C, Indices); 01409 } 01410 01411 Constant *ConstantExpr::getTy(const Type *ReqTy, unsigned Opcode, 01412 Constant *C1, Constant *C2) { 01413 if (Opcode == Instruction::Shl || Opcode == Instruction::Shr) 01414 return getShiftTy(ReqTy, Opcode, C1, C2); 01415 // Check the operands for consistency first 01416 assert((Opcode >= Instruction::BinaryOpsBegin && 01417 Opcode < Instruction::BinaryOpsEnd) && 01418 "Invalid opcode in binary constant expression"); 01419 assert(C1->getType() == C2->getType() && 01420 "Operand types in binary constant expression should match"); 01421 01422 if (ReqTy == C1->getType() || (Instruction::isRelational(Opcode) && 01423 ReqTy == Type::BoolTy)) 01424 if (Constant *FC = ConstantFoldBinaryInstruction(Opcode, C1, C2)) 01425 return FC; // Fold a few common cases... 01426 01427 std::vector<Constant*> argVec(1, C1); argVec.push_back(C2); 01428 ExprMapKeyType Key = std::make_pair(Opcode, argVec); 01429 return ExprConstants.getOrCreate(ReqTy, Key); 01430 } 01431 01432 Constant *ConstantExpr::get(unsigned Opcode, Constant *C1, Constant *C2) { 01433 #ifndef NDEBUG 01434 switch (Opcode) { 01435 case Instruction::Add: case Instruction::Sub: 01436 case Instruction::Mul: case Instruction::Div: 01437 case Instruction::Rem: 01438 assert(C1->getType() == C2->getType() && "Op types should be identical!"); 01439 assert((C1->getType()->isInteger() || C1->getType()->isFloatingPoint() || 01440 isa<PackedType>(C1->getType())) && 01441 "Tried to create an arithmetic operation on a non-arithmetic type!"); 01442 break; 01443 case Instruction::And: 01444 case Instruction::Or: 01445 case Instruction::Xor: 01446 assert(C1->getType() == C2->getType() && "Op types should be identical!"); 01447 assert((C1->getType()->isIntegral() || isa<PackedType>(C1->getType())) && 01448 "Tried to create a logical operation on a non-integral type!"); 01449 break; 01450 case Instruction::SetLT: case Instruction::SetGT: case Instruction::SetLE: 01451 case Instruction::SetGE: case Instruction::SetEQ: case Instruction::SetNE: 01452 assert(C1->getType() == C2->getType() && "Op types should be identical!"); 01453 break; 01454 case Instruction::Shl: 01455 case Instruction::Shr: 01456 assert(C2->getType() == Type::UByteTy && "Shift should be by ubyte!"); 01457 assert((C1->getType()->isInteger() || isa<PackedType>(C1->getType())) && 01458 "Tried to create a shift operation on a non-integer type!"); 01459 break; 01460 default: 01461 break; 01462 } 01463 #endif 01464 01465 if (Instruction::isRelational(Opcode)) 01466 return getTy(Type::BoolTy, Opcode, C1, C2); 01467 else 01468 return getTy(C1->getType(), Opcode, C1, C2); 01469 } 01470 01471 Constant *ConstantExpr::getSelectTy(const Type *ReqTy, Constant *C, 01472 Constant *V1, Constant *V2) { 01473 assert(C->getType() == Type::BoolTy && "Select condition must be bool!"); 01474 assert(V1->getType() == V2->getType() && "Select value types must match!"); 01475 assert(V1->getType()->isFirstClassType() && "Cannot select aggregate type!"); 01476 01477 if (ReqTy == V1->getType()) 01478 if (Constant *SC = ConstantFoldSelectInstruction(C, V1, V2)) 01479 return SC; // Fold common cases 01480 01481 std::vector<Constant*> argVec(3, C); 01482 argVec[1] = V1; 01483 argVec[2] = V2; 01484 ExprMapKeyType Key = std::make_pair(Instruction::Select, argVec); 01485 return ExprConstants.getOrCreate(ReqTy, Key); 01486 } 01487 01488 /// getShiftTy - Return a shift left or shift right constant expr 01489 Constant *ConstantExpr::getShiftTy(const Type *ReqTy, unsigned Opcode, 01490 Constant *C1, Constant *C2) { 01491 // Check the operands for consistency first 01492 assert((Opcode == Instruction::Shl || 01493 Opcode == Instruction::Shr) && 01494 "Invalid opcode in binary constant expression"); 01495 assert(C1->getType()->isIntegral() && C2->getType() == Type::UByteTy && 01496 "Invalid operand types for Shift constant expr!"); 01497 01498 if (Constant *FC = ConstantFoldBinaryInstruction(Opcode, C1, C2)) 01499 return FC; // Fold a few common cases... 01500 01501 // Look up the constant in the table first to ensure uniqueness 01502 std::vector<Constant*> argVec(1, C1); argVec.push_back(C2); 01503 ExprMapKeyType Key = std::make_pair(Opcode, argVec); 01504 return ExprConstants.getOrCreate(ReqTy, Key); 01505 } 01506 01507 01508 Constant *ConstantExpr::getGetElementPtrTy(const Type *ReqTy, Constant *C, 01509 const std::vector<Value*> &IdxList) { 01510 assert(GetElementPtrInst::getIndexedType(C->getType(), IdxList, true) && 01511 "GEP indices invalid!"); 01512 01513 if (Constant *FC = ConstantFoldGetElementPtr(C, IdxList)) 01514 return FC; // Fold a few common cases... 01515 01516 assert(isa<PointerType>(C->getType()) && 01517 "Non-pointer type for constant GetElementPtr expression"); 01518 // Look up the constant in the table first to ensure uniqueness 01519 std::vector<Constant*> ArgVec; 01520 ArgVec.reserve(IdxList.size()+1); 01521 ArgVec.push_back(C); 01522 for (unsigned i = 0, e = IdxList.size(); i != e; ++i) 01523 ArgVec.push_back(cast<Constant>(IdxList[i])); 01524 const ExprMapKeyType &Key = std::make_pair(Instruction::GetElementPtr,ArgVec); 01525 return ExprConstants.getOrCreate(ReqTy, Key); 01526 } 01527 01528 Constant *ConstantExpr::getGetElementPtr(Constant *C, 01529 const std::vector<Constant*> &IdxList){ 01530 // Get the result type of the getelementptr! 01531 std::vector<Value*> VIdxList(IdxList.begin(), IdxList.end()); 01532 01533 const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(), VIdxList, 01534 true); 01535 assert(Ty && "GEP indices invalid!"); 01536 return getGetElementPtrTy(PointerType::get(Ty), C, VIdxList); 01537 } 01538 01539 Constant *ConstantExpr::getGetElementPtr(Constant *C, 01540 const std::vector<Value*> &IdxList) { 01541 // Get the result type of the getelementptr! 01542 const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(), IdxList, 01543 true); 01544 assert(Ty && "GEP indices invalid!"); 01545 return getGetElementPtrTy(PointerType::get(Ty), C, IdxList); 01546 } 01547 01548 Constant *ConstantExpr::getExtractElementTy(const Type *ReqTy, Constant *Val, 01549 Constant *Idx) { 01550 if (Constant *FC = ConstantFoldExtractElementInstruction(Val, Idx)) 01551 return FC; // Fold a few common cases... 01552 // Look up the constant in the table first to ensure uniqueness 01553 std::vector<Constant*> ArgVec(1, Val); 01554 ArgVec.push_back(Idx); 01555 const ExprMapKeyType &Key = std::make_pair(Instruction::ExtractElement,ArgVec); 01556 return ExprConstants.getOrCreate(ReqTy, Key); 01557 } 01558 01559 Constant *ConstantExpr::getExtractElement(Constant *Val, Constant *Idx) { 01560 assert(isa<PackedType>(Val->getType()) && 01561 "Tried to create extractelement operation on non-packed type!"); 01562 assert(Idx->getType() == Type::UIntTy && 01563 "Extractelement index must be uint type!"); 01564 return getExtractElementTy(cast<PackedType>(Val->getType())->getElementType(), 01565 Val, Idx); 01566 } 01567 01568 Constant *ConstantExpr::getInsertElementTy(const Type *ReqTy, Constant *Val, 01569 Constant *Elt, Constant *Idx) { 01570 if (Constant *FC = ConstantFoldInsertElementInstruction(Val, Elt, Idx)) 01571 return FC; // Fold a few common cases... 01572 // Look up the constant in the table first to ensure uniqueness 01573 std::vector<Constant*> ArgVec(1, Val); 01574 ArgVec.push_back(Elt); 01575 ArgVec.push_back(Idx); 01576 const ExprMapKeyType &Key = std::make_pair(Instruction::InsertElement,ArgVec); 01577 return ExprConstants.getOrCreate(ReqTy, Key); 01578 } 01579 01580 Constant *ConstantExpr::getInsertElement(Constant *Val, Constant *Elt, 01581 Constant *Idx) { 01582 assert(isa<PackedType>(Val->getType()) && 01583 "Tried to create insertelement operation on non-packed type!"); 01584 assert(Elt->getType() == cast<PackedType>(Val->getType())->getElementType() 01585 && "Insertelement types must match!"); 01586 assert(Idx->getType() == Type::UIntTy && 01587 "Insertelement index must be uint type!"); 01588 return getInsertElementTy(cast<PackedType>(Val->getType())->getElementType(), 01589 Val, Elt, Idx); 01590 } 01591 01592 Constant *ConstantExpr::getShuffleVectorTy(const Type *ReqTy, Constant *V1, 01593 Constant *V2, Constant *Mask) { 01594 if (Constant *FC = ConstantFoldShuffleVectorInstruction(V1, V2, Mask)) 01595 return FC; // Fold a few common cases... 01596 // Look up the constant in the table first to ensure uniqueness 01597 std::vector<Constant*> ArgVec(1, V1); 01598 ArgVec.push_back(V2); 01599 ArgVec.push_back(Mask); 01600 const ExprMapKeyType &Key = std::make_pair(Instruction::ShuffleVector,ArgVec); 01601 return ExprConstants.getOrCreate(ReqTy, Key); 01602 } 01603 01604 Constant *ConstantExpr::getShuffleVector(Constant *V1, Constant *V2, 01605 Constant *Mask) { 01606 assert(ShuffleVectorInst::isValidOperands(V1, V2, Mask) && 01607 "Invalid shuffle vector constant expr operands!"); 01608 return getShuffleVectorTy(V1->getType(), V1, V2, Mask); 01609 } 01610 01611 01612 // destroyConstant - Remove the constant from the constant table... 01613 // 01614 void ConstantExpr::destroyConstant() { 01615 ExprConstants.remove(this); 01616 destroyConstantImpl(); 01617 } 01618 01619 const char *ConstantExpr::getOpcodeName() const { 01620 return Instruction::getOpcodeName(getOpcode()); 01621 } 01622 01623 //===----------------------------------------------------------------------===// 01624 // replaceUsesOfWithOnConstant implementations 01625 01626 void ConstantArray::replaceUsesOfWithOnConstant(Value *From, Value *To, 01627 Use *U) { 01628 assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!"); 01629 Constant *ToC = cast<Constant>(To); 01630 01631 unsigned OperandToUpdate = U-OperandList; 01632 assert(getOperand(OperandToUpdate) == From && "ReplaceAllUsesWith broken!"); 01633 01634 std::pair<ArrayConstantsTy::MapKey, Constant*> Lookup; 01635 Lookup.first.first = getType(); 01636 Lookup.second = this; 01637 01638 std::vector<Constant*> &Values = Lookup.first.second; 01639 Values.reserve(getNumOperands()); // Build replacement array. 01640 01641 // Fill values with the modified operands of the constant array. Also, 01642 // compute whether this turns into an all-zeros array. 01643 bool isAllZeros = false; 01644 if (!ToC->isNullValue()) { 01645 for (Use *O = OperandList, *E = OperandList+getNumOperands(); O != E; ++O) 01646 Values.push_back(cast<Constant>(O->get())); 01647 } else { 01648 isAllZeros = true; 01649 for (Use *O = OperandList, *E = OperandList+getNumOperands(); O != E; ++O) { 01650 Constant *Val = cast<Constant>(O->get()); 01651 Values.push_back(Val); 01652 if (isAllZeros) isAllZeros = Val->isNullValue(); 01653 } 01654 } 01655 Values[OperandToUpdate] = ToC; 01656 01657 Constant *Replacement = 0; 01658 if (isAllZeros) { 01659 Replacement = ConstantAggregateZero::get(getType()); 01660 } else { 01661 // Check to see if we have this array type already. 01662 bool Exists; 01663 ArrayConstantsTy::MapTy::iterator I = 01664 ArrayConstants.InsertOrGetItem(Lookup, Exists); 01665 01666 if (Exists) { 01667 Replacement = I->second; 01668 } else { 01669 // Okay, the new shape doesn't exist in the system yet. Instead of 01670 // creating a new constant array, inserting it, replaceallusesof'ing the 01671 // old with the new, then deleting the old... just update the current one 01672 // in place! 01673 ArrayConstants.MoveConstantToNewSlot(this, I); 01674 01675 // Update to the new value. 01676 setOperand(OperandToUpdate, ToC); 01677 return; 01678 } 01679 } 01680 01681 // Otherwise, I do need to replace this with an existing value. 01682 assert(Replacement != this && "I didn't contain From!"); 01683 01684 // Everyone using this now uses the replacement. 01685 uncheckedReplaceAllUsesWith(Replacement); 01686 01687 // Delete the old constant! 01688 destroyConstant(); 01689 } 01690 01691 void ConstantStruct::replaceUsesOfWithOnConstant(Value *From, Value *To, 01692 Use *U) { 01693 assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!"); 01694 Constant *ToC = cast<Constant>(To); 01695 01696 unsigned OperandToUpdate = U-OperandList; 01697 assert(getOperand(OperandToUpdate) == From && "ReplaceAllUsesWith broken!"); 01698 01699 std::pair<StructConstantsTy::MapKey, Constant*> Lookup; 01700 Lookup.first.first = getType(); 01701 Lookup.second = this; 01702 std::vector<Constant*> &Values = Lookup.first.second; 01703 Values.reserve(getNumOperands()); // Build replacement struct. 01704 01705 01706 // Fill values with the modified operands of the constant struct. Also, 01707 // compute whether this turns into an all-zeros struct. 01708 bool isAllZeros = false; 01709 if (!ToC->isNullValue()) { 01710 for (Use *O = OperandList, *E = OperandList+getNumOperands(); O != E; ++O) 01711 Values.push_back(cast<Constant>(O->get())); 01712 } else { 01713 isAllZeros = true; 01714 for (Use *O = OperandList, *E = OperandList+getNumOperands(); O != E; ++O) { 01715 Constant *Val = cast<Constant>(O->get()); 01716 Values.push_back(Val); 01717 if (isAllZeros) isAllZeros = Val->isNullValue(); 01718 } 01719 } 01720 Values[OperandToUpdate] = ToC; 01721 01722 Constant *Replacement = 0; 01723 if (isAllZeros) { 01724 Replacement = ConstantAggregateZero::get(getType()); 01725 } else { 01726 // Check to see if we have this array type already. 01727 bool Exists; 01728 StructConstantsTy::MapTy::iterator I = 01729 StructConstants.InsertOrGetItem(Lookup, Exists); 01730 01731 if (Exists) { 01732 Replacement = I->second; 01733 } else { 01734 // Okay, the new shape doesn't exist in the system yet. Instead of 01735 // creating a new constant struct, inserting it, replaceallusesof'ing the 01736 // old with the new, then deleting the old... just update the current one 01737 // in place! 01738 StructConstants.MoveConstantToNewSlot(this, I); 01739 01740 // Update to the new value. 01741 setOperand(OperandToUpdate, ToC); 01742 return; 01743 } 01744 } 01745 01746 assert(Replacement != this && "I didn't contain From!"); 01747 01748 // Everyone using this now uses the replacement. 01749 uncheckedReplaceAllUsesWith(Replacement); 01750 01751 // Delete the old constant! 01752 destroyConstant(); 01753 } 01754 01755 void ConstantPacked::replaceUsesOfWithOnConstant(Value *From, Value *To, 01756 Use *U) { 01757 assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!"); 01758 01759 std::vector<Constant*> Values; 01760 Values.reserve(getNumOperands()); // Build replacement array... 01761 for (unsigned i = 0, e = getNumOperands(); i != e; ++i) { 01762 Constant *Val = getOperand(i); 01763 if (Val == From) Val = cast<Constant>(To); 01764 Values.push_back(Val); 01765 } 01766 01767 Constant *Replacement = ConstantPacked::get(getType(), Values); 01768 assert(Replacement != this && "I didn't contain From!"); 01769 01770 // Everyone using this now uses the replacement. 01771 uncheckedReplaceAllUsesWith(Replacement); 01772 01773 // Delete the old constant! 01774 destroyConstant(); 01775 } 01776 01777 void ConstantExpr::replaceUsesOfWithOnConstant(Value *From, Value *ToV, 01778 Use *U) { 01779 assert(isa<Constant>(ToV) && "Cannot make Constant refer to non-constant!"); 01780 Constant *To = cast<Constant>(ToV); 01781 01782 Constant *Replacement = 0; 01783 if (getOpcode() == Instruction::GetElementPtr) { 01784 std::vector<Constant*> Indices; 01785 Constant *Pointer = getOperand(0); 01786 Indices.reserve(getNumOperands()-1); 01787 if (Pointer == From) Pointer = To; 01788 01789 for (unsigned i = 1, e = getNumOperands(); i != e; ++i) { 01790 Constant *Val = getOperand(i); 01791 if (Val == From) Val = To; 01792 Indices.push_back(Val); 01793 } 01794 Replacement = ConstantExpr::getGetElementPtr(Pointer, Indices); 01795 } else if (getOpcode() == Instruction::Cast) { 01796 assert(getOperand(0) == From && "Cast only has one use!"); 01797 Replacement = ConstantExpr::getCast(To, getType()); 01798 } else if (getOpcode() == Instruction::Select) { 01799 Constant *C1 = getOperand(0); 01800 Constant *C2 = getOperand(1); 01801 Constant *C3 = getOperand(2); 01802 if (C1 == From) C1 = To; 01803 if (C2 == From) C2 = To; 01804 if (C3 == From) C3 = To; 01805 Replacement = ConstantExpr::getSelect(C1, C2, C3); 01806 } else if (getOpcode() == Instruction::ExtractElement) { 01807 Constant *C1 = getOperand(0); 01808 Constant *C2 = getOperand(1); 01809 if (C1 == From) C1 = To; 01810 if (C2 == From) C2 = To; 01811 Replacement = ConstantExpr::getExtractElement(C1, C2); 01812 } else if (getOpcode() == Instruction::InsertElement) { 01813 Constant *C1 = getOperand(0); 01814 Constant *C2 = getOperand(1); 01815 Constant *C3 = getOperand(1); 01816 if (C1 == From) C1 = To; 01817 if (C2 == From) C2 = To; 01818 if (C3 == From) C3 = To; 01819 Replacement = ConstantExpr::getInsertElement(C1, C2, C3); 01820 } else if (getOpcode() == Instruction::ShuffleVector) { 01821 Constant *C1 = getOperand(0); 01822 Constant *C2 = getOperand(1); 01823 Constant *C3 = getOperand(2); 01824 if (C1 == From) C1 = To; 01825 if (C2 == From) C2 = To; 01826 if (C3 == From) C3 = To; 01827 Replacement = ConstantExpr::getShuffleVector(C1, C2, C3); 01828 } else if (getNumOperands() == 2) { 01829 Constant *C1 = getOperand(0); 01830 Constant *C2 = getOperand(1); 01831 if (C1 == From) C1 = To; 01832 if (C2 == From) C2 = To; 01833 Replacement = ConstantExpr::get(getOpcode(), C1, C2); 01834 } else { 01835 assert(0 && "Unknown ConstantExpr type!"); 01836 return; 01837 } 01838 01839 assert(Replacement != this && "I didn't contain From!"); 01840 01841 // Everyone using this now uses the replacement. 01842 uncheckedReplaceAllUsesWith(Replacement); 01843 01844 // Delete the old constant! 01845 destroyConstant(); 01846 } 01847 01848 01849 01850 /// clearAllValueMaps - This method frees all internal memory used by the 01851 /// constant subsystem, which can be used in environments where this memory 01852 /// is otherwise reported as a leak. 01853 void Constant::clearAllValueMaps() { 01854 std::vector<Constant *> Constants; 01855 01856 DoubleConstants.clear(Constants); 01857 FloatConstants.clear(Constants); 01858 SIntConstants.clear(Constants); 01859 UIntConstants.clear(Constants); 01860 AggZeroConstants.clear(Constants); 01861 ArrayConstants.clear(Constants); 01862 StructConstants.clear(Constants); 01863 PackedConstants.clear(Constants); 01864 NullPtrConstants.clear(Constants); 01865 UndefValueConstants.clear(Constants); 01866 ExprConstants.clear(Constants); 01867 01868 for (std::vector<Constant *>::iterator I = Constants.begin(), 01869 E = Constants.end(); I != E; ++I) 01870 (*I)->dropAllReferences(); 01871 for (std::vector<Constant *>::iterator I = Constants.begin(), 01872 E = Constants.end(); I != E; ++I) 01873 (*I)->destroyConstantImpl(); 01874 Constants.clear(); 01875 } 01876 01877 /// getStringValue - Turn an LLVM constant pointer that eventually points to a 01878 /// global into a string value. Return an empty string if we can't do it. 01879 /// Parameter Chop determines if the result is chopped at the first null 01880 /// terminator. 01881 /// 01882 std::string Constant::getStringValue(bool Chop, unsigned Offset) { 01883 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(this)) { 01884 if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) { 01885 ConstantArray *Init = cast<ConstantArray>(GV->getInitializer()); 01886 if (Init->isString()) { 01887 std::string Result = Init->getAsString(); 01888 if (Offset < Result.size()) { 01889 // If we are pointing INTO The string, erase the beginning... 01890 Result.erase(Result.begin(), Result.begin()+Offset); 01891 01892 // Take off the null terminator, and any string fragments after it. 01893 if (Chop) { 01894 std::string::size_type NullPos = Result.find_first_of((char)0); 01895 if (NullPos != std::string::npos) 01896 Result.erase(Result.begin()+NullPos, Result.end()); 01897 } 01898 return Result; 01899 } 01900 } 01901 } 01902 } else if (Constant *C = dyn_cast<Constant>(this)) { 01903 if (GlobalValue *GV = dyn_cast<GlobalValue>(C)) 01904 return GV->getStringValue(Chop, Offset); 01905 else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { 01906 if (CE->getOpcode() == Instruction::GetElementPtr) { 01907 // Turn a gep into the specified offset. 01908 if (CE->getNumOperands() == 3 && 01909 cast<Constant>(CE->getOperand(1))->isNullValue() && 01910 isa<ConstantInt>(CE->getOperand(2))) { 01911 Offset += cast<ConstantInt>(CE->getOperand(2))->getRawValue(); 01912 return CE->getOperand(0)->getStringValue(Chop, Offset); 01913 } 01914 } 01915 } 01916 } 01917 return ""; 01918 } 01919