LLVM API Documentation
00001 //===-- Type.cpp - Implement the Type class -------------------------------===// 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 Type class for the VMCore library. 00011 // 00012 //===----------------------------------------------------------------------===// 00013 00014 #include "llvm/AbstractTypeUser.h" 00015 #include "llvm/DerivedTypes.h" 00016 #include "llvm/SymbolTable.h" 00017 #include "llvm/Constants.h" 00018 #include "llvm/ADT/DepthFirstIterator.h" 00019 #include "llvm/ADT/StringExtras.h" 00020 #include "llvm/ADT/SCCIterator.h" 00021 #include "llvm/ADT/STLExtras.h" 00022 #include "llvm/Support/MathExtras.h" 00023 #include <algorithm> 00024 #include <iostream> 00025 using namespace llvm; 00026 00027 // DEBUG_MERGE_TYPES - Enable this #define to see how and when derived types are 00028 // created and later destroyed, all in an effort to make sure that there is only 00029 // a single canonical version of a type. 00030 // 00031 //#define DEBUG_MERGE_TYPES 1 00032 00033 AbstractTypeUser::~AbstractTypeUser() {} 00034 00035 //===----------------------------------------------------------------------===// 00036 // Type Class Implementation 00037 //===----------------------------------------------------------------------===// 00038 00039 // Concrete/Abstract TypeDescriptions - We lazily calculate type descriptions 00040 // for types as they are needed. Because resolution of types must invalidate 00041 // all of the abstract type descriptions, we keep them in a seperate map to make 00042 // this easy. 00043 static std::map<const Type*, std::string> ConcreteTypeDescriptions; 00044 static std::map<const Type*, std::string> AbstractTypeDescriptions; 00045 00046 Type::Type(const char *Name, TypeID id) 00047 : ID(id), Abstract(false), RefCount(0), ForwardType(0) { 00048 assert(Name && Name[0] && "Should use other ctor if no name!"); 00049 ConcreteTypeDescriptions[this] = Name; 00050 } 00051 00052 00053 const Type *Type::getPrimitiveType(TypeID IDNumber) { 00054 switch (IDNumber) { 00055 case VoidTyID : return VoidTy; 00056 case BoolTyID : return BoolTy; 00057 case UByteTyID : return UByteTy; 00058 case SByteTyID : return SByteTy; 00059 case UShortTyID: return UShortTy; 00060 case ShortTyID : return ShortTy; 00061 case UIntTyID : return UIntTy; 00062 case IntTyID : return IntTy; 00063 case ULongTyID : return ULongTy; 00064 case LongTyID : return LongTy; 00065 case FloatTyID : return FloatTy; 00066 case DoubleTyID: return DoubleTy; 00067 case LabelTyID : return LabelTy; 00068 default: 00069 return 0; 00070 } 00071 } 00072 00073 // isLosslesslyConvertibleTo - Return true if this type can be converted to 00074 // 'Ty' without any reinterpretation of bits. For example, uint to int. 00075 // 00076 bool Type::isLosslesslyConvertibleTo(const Type *Ty) const { 00077 if (this == Ty) return true; 00078 00079 // Packed type conversions are always bitwise. 00080 if (isa<PackedType>(this) && isa<PackedType>(Ty)) 00081 return true; 00082 00083 if ((!isPrimitiveType() && !isa<PointerType>(this)) || 00084 (!isa<PointerType>(Ty) && !Ty->isPrimitiveType())) return false; 00085 00086 if (getTypeID() == Ty->getTypeID()) 00087 return true; // Handles identity cast, and cast of differing pointer types 00088 00089 // Now we know that they are two differing primitive or pointer types 00090 switch (getTypeID()) { 00091 case Type::UByteTyID: return Ty == Type::SByteTy; 00092 case Type::SByteTyID: return Ty == Type::UByteTy; 00093 case Type::UShortTyID: return Ty == Type::ShortTy; 00094 case Type::ShortTyID: return Ty == Type::UShortTy; 00095 case Type::UIntTyID: return Ty == Type::IntTy; 00096 case Type::IntTyID: return Ty == Type::UIntTy; 00097 case Type::ULongTyID: return Ty == Type::LongTy; 00098 case Type::LongTyID: return Ty == Type::ULongTy; 00099 case Type::PointerTyID: return isa<PointerType>(Ty); 00100 default: 00101 return false; // Other types have no identity values 00102 } 00103 } 00104 00105 /// getUnsignedVersion - If this is an integer type, return the unsigned 00106 /// variant of this type. For example int -> uint. 00107 const Type *Type::getUnsignedVersion() const { 00108 switch (getTypeID()) { 00109 default: 00110 assert(isInteger()&&"Type::getUnsignedVersion is only valid for integers!"); 00111 case Type::UByteTyID: 00112 case Type::SByteTyID: return Type::UByteTy; 00113 case Type::UShortTyID: 00114 case Type::ShortTyID: return Type::UShortTy; 00115 case Type::UIntTyID: 00116 case Type::IntTyID: return Type::UIntTy; 00117 case Type::ULongTyID: 00118 case Type::LongTyID: return Type::ULongTy; 00119 } 00120 } 00121 00122 /// getSignedVersion - If this is an integer type, return the signed variant 00123 /// of this type. For example uint -> int. 00124 const Type *Type::getSignedVersion() const { 00125 switch (getTypeID()) { 00126 default: 00127 assert(isInteger() && "Type::getSignedVersion is only valid for integers!"); 00128 case Type::UByteTyID: 00129 case Type::SByteTyID: return Type::SByteTy; 00130 case Type::UShortTyID: 00131 case Type::ShortTyID: return Type::ShortTy; 00132 case Type::UIntTyID: 00133 case Type::IntTyID: return Type::IntTy; 00134 case Type::ULongTyID: 00135 case Type::LongTyID: return Type::LongTy; 00136 } 00137 } 00138 00139 00140 // getPrimitiveSize - Return the basic size of this type if it is a primitive 00141 // type. These are fixed by LLVM and are not target dependent. This will 00142 // return zero if the type does not have a size or is not a primitive type. 00143 // 00144 unsigned Type::getPrimitiveSize() const { 00145 switch (getTypeID()) { 00146 case Type::BoolTyID: 00147 case Type::SByteTyID: 00148 case Type::UByteTyID: return 1; 00149 case Type::UShortTyID: 00150 case Type::ShortTyID: return 2; 00151 case Type::FloatTyID: 00152 case Type::IntTyID: 00153 case Type::UIntTyID: return 4; 00154 case Type::LongTyID: 00155 case Type::ULongTyID: 00156 case Type::DoubleTyID: return 8; 00157 default: return 0; 00158 } 00159 } 00160 00161 unsigned Type::getPrimitiveSizeInBits() const { 00162 switch (getTypeID()) { 00163 case Type::BoolTyID: return 1; 00164 case Type::SByteTyID: 00165 case Type::UByteTyID: return 8; 00166 case Type::UShortTyID: 00167 case Type::ShortTyID: return 16; 00168 case Type::FloatTyID: 00169 case Type::IntTyID: 00170 case Type::UIntTyID: return 32; 00171 case Type::LongTyID: 00172 case Type::ULongTyID: 00173 case Type::DoubleTyID: return 64; 00174 default: return 0; 00175 } 00176 } 00177 00178 /// isSizedDerivedType - Derived types like structures and arrays are sized 00179 /// iff all of the members of the type are sized as well. Since asking for 00180 /// their size is relatively uncommon, move this operation out of line. 00181 bool Type::isSizedDerivedType() const { 00182 if (const ArrayType *ATy = dyn_cast<ArrayType>(this)) 00183 return ATy->getElementType()->isSized(); 00184 00185 if (const PackedType *PTy = dyn_cast<PackedType>(this)) 00186 return PTy->getElementType()->isSized(); 00187 00188 if (!isa<StructType>(this)) return false; 00189 00190 // Okay, our struct is sized if all of the elements are... 00191 for (subtype_iterator I = subtype_begin(), E = subtype_end(); I != E; ++I) 00192 if (!(*I)->isSized()) return false; 00193 00194 return true; 00195 } 00196 00197 /// getForwardedTypeInternal - This method is used to implement the union-find 00198 /// algorithm for when a type is being forwarded to another type. 00199 const Type *Type::getForwardedTypeInternal() const { 00200 assert(ForwardType && "This type is not being forwarded to another type!"); 00201 00202 // Check to see if the forwarded type has been forwarded on. If so, collapse 00203 // the forwarding links. 00204 const Type *RealForwardedType = ForwardType->getForwardedType(); 00205 if (!RealForwardedType) 00206 return ForwardType; // No it's not forwarded again 00207 00208 // Yes, it is forwarded again. First thing, add the reference to the new 00209 // forward type. 00210 if (RealForwardedType->isAbstract()) 00211 cast<DerivedType>(RealForwardedType)->addRef(); 00212 00213 // Now drop the old reference. This could cause ForwardType to get deleted. 00214 cast<DerivedType>(ForwardType)->dropRef(); 00215 00216 // Return the updated type. 00217 ForwardType = RealForwardedType; 00218 return ForwardType; 00219 } 00220 00221 void Type::refineAbstractType(const DerivedType *OldTy, const Type *NewTy) { 00222 abort(); 00223 } 00224 void Type::typeBecameConcrete(const DerivedType *AbsTy) { 00225 abort(); 00226 } 00227 00228 00229 // getTypeDescription - This is a recursive function that walks a type hierarchy 00230 // calculating the description for a type. 00231 // 00232 static std::string getTypeDescription(const Type *Ty, 00233 std::vector<const Type *> &TypeStack) { 00234 if (isa<OpaqueType>(Ty)) { // Base case for the recursion 00235 std::map<const Type*, std::string>::iterator I = 00236 AbstractTypeDescriptions.lower_bound(Ty); 00237 if (I != AbstractTypeDescriptions.end() && I->first == Ty) 00238 return I->second; 00239 std::string Desc = "opaque"; 00240 AbstractTypeDescriptions.insert(std::make_pair(Ty, Desc)); 00241 return Desc; 00242 } 00243 00244 if (!Ty->isAbstract()) { // Base case for the recursion 00245 std::map<const Type*, std::string>::iterator I = 00246 ConcreteTypeDescriptions.find(Ty); 00247 if (I != ConcreteTypeDescriptions.end()) return I->second; 00248 } 00249 00250 // Check to see if the Type is already on the stack... 00251 unsigned Slot = 0, CurSize = TypeStack.size(); 00252 while (Slot < CurSize && TypeStack[Slot] != Ty) ++Slot; // Scan for type 00253 00254 // This is another base case for the recursion. In this case, we know 00255 // that we have looped back to a type that we have previously visited. 00256 // Generate the appropriate upreference to handle this. 00257 // 00258 if (Slot < CurSize) 00259 return "\\" + utostr(CurSize-Slot); // Here's the upreference 00260 00261 // Recursive case: derived types... 00262 std::string Result; 00263 TypeStack.push_back(Ty); // Add us to the stack.. 00264 00265 switch (Ty->getTypeID()) { 00266 case Type::FunctionTyID: { 00267 const FunctionType *FTy = cast<FunctionType>(Ty); 00268 Result = getTypeDescription(FTy->getReturnType(), TypeStack) + " ("; 00269 for (FunctionType::param_iterator I = FTy->param_begin(), 00270 E = FTy->param_end(); I != E; ++I) { 00271 if (I != FTy->param_begin()) 00272 Result += ", "; 00273 Result += getTypeDescription(*I, TypeStack); 00274 } 00275 if (FTy->isVarArg()) { 00276 if (FTy->getNumParams()) Result += ", "; 00277 Result += "..."; 00278 } 00279 Result += ")"; 00280 break; 00281 } 00282 case Type::StructTyID: { 00283 const StructType *STy = cast<StructType>(Ty); 00284 Result = "{ "; 00285 for (StructType::element_iterator I = STy->element_begin(), 00286 E = STy->element_end(); I != E; ++I) { 00287 if (I != STy->element_begin()) 00288 Result += ", "; 00289 Result += getTypeDescription(*I, TypeStack); 00290 } 00291 Result += " }"; 00292 break; 00293 } 00294 case Type::PointerTyID: { 00295 const PointerType *PTy = cast<PointerType>(Ty); 00296 Result = getTypeDescription(PTy->getElementType(), TypeStack) + " *"; 00297 break; 00298 } 00299 case Type::ArrayTyID: { 00300 const ArrayType *ATy = cast<ArrayType>(Ty); 00301 unsigned NumElements = ATy->getNumElements(); 00302 Result = "["; 00303 Result += utostr(NumElements) + " x "; 00304 Result += getTypeDescription(ATy->getElementType(), TypeStack) + "]"; 00305 break; 00306 } 00307 case Type::PackedTyID: { 00308 const PackedType *PTy = cast<PackedType>(Ty); 00309 unsigned NumElements = PTy->getNumElements(); 00310 Result = "<"; 00311 Result += utostr(NumElements) + " x "; 00312 Result += getTypeDescription(PTy->getElementType(), TypeStack) + ">"; 00313 break; 00314 } 00315 default: 00316 Result = "<error>"; 00317 assert(0 && "Unhandled type in getTypeDescription!"); 00318 } 00319 00320 TypeStack.pop_back(); // Remove self from stack... 00321 00322 return Result; 00323 } 00324 00325 00326 00327 static const std::string &getOrCreateDesc(std::map<const Type*,std::string>&Map, 00328 const Type *Ty) { 00329 std::map<const Type*, std::string>::iterator I = Map.find(Ty); 00330 if (I != Map.end()) return I->second; 00331 00332 std::vector<const Type *> TypeStack; 00333 std::string Result = getTypeDescription(Ty, TypeStack); 00334 return Map[Ty] = Result; 00335 } 00336 00337 00338 const std::string &Type::getDescription() const { 00339 if (isAbstract()) 00340 return getOrCreateDesc(AbstractTypeDescriptions, this); 00341 else 00342 return getOrCreateDesc(ConcreteTypeDescriptions, this); 00343 } 00344 00345 00346 bool StructType::indexValid(const Value *V) const { 00347 // Structure indexes require unsigned integer constants. 00348 if (V->getType() == Type::UIntTy) 00349 if (const ConstantUInt *CU = dyn_cast<ConstantUInt>(V)) 00350 return CU->getValue() < ContainedTys.size(); 00351 return false; 00352 } 00353 00354 // getTypeAtIndex - Given an index value into the type, return the type of the 00355 // element. For a structure type, this must be a constant value... 00356 // 00357 const Type *StructType::getTypeAtIndex(const Value *V) const { 00358 assert(indexValid(V) && "Invalid structure index!"); 00359 unsigned Idx = (unsigned)cast<ConstantUInt>(V)->getValue(); 00360 return ContainedTys[Idx]; 00361 } 00362 00363 00364 //===----------------------------------------------------------------------===// 00365 // Static 'Type' data 00366 //===----------------------------------------------------------------------===// 00367 00368 namespace { 00369 struct PrimType : public Type { 00370 PrimType(const char *S, TypeID ID) : Type(S, ID) {} 00371 }; 00372 } 00373 00374 static PrimType TheVoidTy ("void" , Type::VoidTyID); 00375 static PrimType TheBoolTy ("bool" , Type::BoolTyID); 00376 static PrimType TheSByteTy ("sbyte" , Type::SByteTyID); 00377 static PrimType TheUByteTy ("ubyte" , Type::UByteTyID); 00378 static PrimType TheShortTy ("short" , Type::ShortTyID); 00379 static PrimType TheUShortTy("ushort", Type::UShortTyID); 00380 static PrimType TheIntTy ("int" , Type::IntTyID); 00381 static PrimType TheUIntTy ("uint" , Type::UIntTyID); 00382 static PrimType TheLongTy ("long" , Type::LongTyID); 00383 static PrimType TheULongTy ("ulong" , Type::ULongTyID); 00384 static PrimType TheFloatTy ("float" , Type::FloatTyID); 00385 static PrimType TheDoubleTy("double", Type::DoubleTyID); 00386 static PrimType TheLabelTy ("label" , Type::LabelTyID); 00387 00388 Type *Type::VoidTy = &TheVoidTy; 00389 Type *Type::BoolTy = &TheBoolTy; 00390 Type *Type::SByteTy = &TheSByteTy; 00391 Type *Type::UByteTy = &TheUByteTy; 00392 Type *Type::ShortTy = &TheShortTy; 00393 Type *Type::UShortTy = &TheUShortTy; 00394 Type *Type::IntTy = &TheIntTy; 00395 Type *Type::UIntTy = &TheUIntTy; 00396 Type *Type::LongTy = &TheLongTy; 00397 Type *Type::ULongTy = &TheULongTy; 00398 Type *Type::FloatTy = &TheFloatTy; 00399 Type *Type::DoubleTy = &TheDoubleTy; 00400 Type *Type::LabelTy = &TheLabelTy; 00401 00402 00403 //===----------------------------------------------------------------------===// 00404 // Derived Type Constructors 00405 //===----------------------------------------------------------------------===// 00406 00407 FunctionType::FunctionType(const Type *Result, 00408 const std::vector<const Type*> &Params, 00409 bool IsVarArgs) : DerivedType(FunctionTyID), 00410 isVarArgs(IsVarArgs) { 00411 assert((Result->isFirstClassType() || Result == Type::VoidTy || 00412 isa<OpaqueType>(Result)) && 00413 "LLVM functions cannot return aggregates"); 00414 bool isAbstract = Result->isAbstract(); 00415 ContainedTys.reserve(Params.size()+1); 00416 ContainedTys.push_back(PATypeHandle(Result, this)); 00417 00418 for (unsigned i = 0; i != Params.size(); ++i) { 00419 assert((Params[i]->isFirstClassType() || isa<OpaqueType>(Params[i])) && 00420 "Function arguments must be value types!"); 00421 00422 ContainedTys.push_back(PATypeHandle(Params[i], this)); 00423 isAbstract |= Params[i]->isAbstract(); 00424 } 00425 00426 // Calculate whether or not this type is abstract 00427 setAbstract(isAbstract); 00428 } 00429 00430 StructType::StructType(const std::vector<const Type*> &Types) 00431 : CompositeType(StructTyID) { 00432 ContainedTys.reserve(Types.size()); 00433 bool isAbstract = false; 00434 for (unsigned i = 0; i < Types.size(); ++i) { 00435 assert(Types[i] != Type::VoidTy && "Void type for structure field!!"); 00436 ContainedTys.push_back(PATypeHandle(Types[i], this)); 00437 isAbstract |= Types[i]->isAbstract(); 00438 } 00439 00440 // Calculate whether or not this type is abstract 00441 setAbstract(isAbstract); 00442 } 00443 00444 ArrayType::ArrayType(const Type *ElType, uint64_t NumEl) 00445 : SequentialType(ArrayTyID, ElType) { 00446 NumElements = NumEl; 00447 00448 // Calculate whether or not this type is abstract 00449 setAbstract(ElType->isAbstract()); 00450 } 00451 00452 PackedType::PackedType(const Type *ElType, unsigned NumEl) 00453 : SequentialType(PackedTyID, ElType) { 00454 NumElements = NumEl; 00455 00456 assert(NumEl > 0 && "NumEl of a PackedType must be greater than 0"); 00457 assert((ElType->isIntegral() || ElType->isFloatingPoint()) && 00458 "Elements of a PackedType must be a primitive type"); 00459 } 00460 00461 00462 PointerType::PointerType(const Type *E) : SequentialType(PointerTyID, E) { 00463 // Calculate whether or not this type is abstract 00464 setAbstract(E->isAbstract()); 00465 } 00466 00467 OpaqueType::OpaqueType() : DerivedType(OpaqueTyID) { 00468 setAbstract(true); 00469 #ifdef DEBUG_MERGE_TYPES 00470 std::cerr << "Derived new type: " << *this << "\n"; 00471 #endif 00472 } 00473 00474 // dropAllTypeUses - When this (abstract) type is resolved to be equal to 00475 // another (more concrete) type, we must eliminate all references to other 00476 // types, to avoid some circular reference problems. 00477 void DerivedType::dropAllTypeUses() { 00478 if (!ContainedTys.empty()) { 00479 // The type must stay abstract. To do this, we insert a pointer to a type 00480 // that will never get resolved, thus will always be abstract. 00481 static Type *AlwaysOpaqueTy = OpaqueType::get(); 00482 static PATypeHolder Holder(AlwaysOpaqueTy); 00483 ContainedTys[0] = AlwaysOpaqueTy; 00484 00485 // Change the rest of the types to be intty's. It doesn't matter what we 00486 // pick so long as it doesn't point back to this type. We choose something 00487 // concrete to avoid overhead for adding to AbstracTypeUser lists and stuff. 00488 for (unsigned i = 1, e = ContainedTys.size(); i != e; ++i) 00489 ContainedTys[i] = Type::IntTy; 00490 } 00491 } 00492 00493 00494 00495 /// TypePromotionGraph and graph traits - this is designed to allow us to do 00496 /// efficient SCC processing of type graphs. This is the exact same as 00497 /// GraphTraits<Type*>, except that we pretend that concrete types have no 00498 /// children to avoid processing them. 00499 struct TypePromotionGraph { 00500 Type *Ty; 00501 TypePromotionGraph(Type *T) : Ty(T) {} 00502 }; 00503 00504 namespace llvm { 00505 template <> struct GraphTraits<TypePromotionGraph> { 00506 typedef Type NodeType; 00507 typedef Type::subtype_iterator ChildIteratorType; 00508 00509 static inline NodeType *getEntryNode(TypePromotionGraph G) { return G.Ty; } 00510 static inline ChildIteratorType child_begin(NodeType *N) { 00511 if (N->isAbstract()) 00512 return N->subtype_begin(); 00513 else // No need to process children of concrete types. 00514 return N->subtype_end(); 00515 } 00516 static inline ChildIteratorType child_end(NodeType *N) { 00517 return N->subtype_end(); 00518 } 00519 }; 00520 } 00521 00522 00523 // PromoteAbstractToConcrete - This is a recursive function that walks a type 00524 // graph calculating whether or not a type is abstract. 00525 // 00526 void Type::PromoteAbstractToConcrete() { 00527 if (!isAbstract()) return; 00528 00529 scc_iterator<TypePromotionGraph> SI = scc_begin(TypePromotionGraph(this)); 00530 scc_iterator<TypePromotionGraph> SE = scc_end (TypePromotionGraph(this)); 00531 00532 for (; SI != SE; ++SI) { 00533 std::vector<Type*> &SCC = *SI; 00534 00535 // Concrete types are leaves in the tree. Since an SCC will either be all 00536 // abstract or all concrete, we only need to check one type. 00537 if (SCC[0]->isAbstract()) { 00538 if (isa<OpaqueType>(SCC[0])) 00539 return; // Not going to be concrete, sorry. 00540 00541 // If all of the children of all of the types in this SCC are concrete, 00542 // then this SCC is now concrete as well. If not, neither this SCC, nor 00543 // any parent SCCs will be concrete, so we might as well just exit. 00544 for (unsigned i = 0, e = SCC.size(); i != e; ++i) 00545 for (Type::subtype_iterator CI = SCC[i]->subtype_begin(), 00546 E = SCC[i]->subtype_end(); CI != E; ++CI) 00547 if ((*CI)->isAbstract()) 00548 // If the child type is in our SCC, it doesn't make the entire SCC 00549 // abstract unless there is a non-SCC abstract type. 00550 if (std::find(SCC.begin(), SCC.end(), *CI) == SCC.end()) 00551 return; // Not going to be concrete, sorry. 00552 00553 // Okay, we just discovered this whole SCC is now concrete, mark it as 00554 // such! 00555 for (unsigned i = 0, e = SCC.size(); i != e; ++i) { 00556 assert(SCC[i]->isAbstract() && "Why are we processing concrete types?"); 00557 00558 SCC[i]->setAbstract(false); 00559 } 00560 00561 for (unsigned i = 0, e = SCC.size(); i != e; ++i) { 00562 assert(!SCC[i]->isAbstract() && "Concrete type became abstract?"); 00563 // The type just became concrete, notify all users! 00564 cast<DerivedType>(SCC[i])->notifyUsesThatTypeBecameConcrete(); 00565 } 00566 } 00567 } 00568 } 00569 00570 00571 //===----------------------------------------------------------------------===// 00572 // Type Structural Equality Testing 00573 //===----------------------------------------------------------------------===// 00574 00575 // TypesEqual - Two types are considered structurally equal if they have the 00576 // same "shape": Every level and element of the types have identical primitive 00577 // ID's, and the graphs have the same edges/nodes in them. Nodes do not have to 00578 // be pointer equals to be equivalent though. This uses an optimistic algorithm 00579 // that assumes that two graphs are the same until proven otherwise. 00580 // 00581 static bool TypesEqual(const Type *Ty, const Type *Ty2, 00582 std::map<const Type *, const Type *> &EqTypes) { 00583 if (Ty == Ty2) return true; 00584 if (Ty->getTypeID() != Ty2->getTypeID()) return false; 00585 if (isa<OpaqueType>(Ty)) 00586 return false; // Two unequal opaque types are never equal 00587 00588 std::map<const Type*, const Type*>::iterator It = EqTypes.lower_bound(Ty); 00589 if (It != EqTypes.end() && It->first == Ty) 00590 return It->second == Ty2; // Looping back on a type, check for equality 00591 00592 // Otherwise, add the mapping to the table to make sure we don't get 00593 // recursion on the types... 00594 EqTypes.insert(It, std::make_pair(Ty, Ty2)); 00595 00596 // Two really annoying special cases that breaks an otherwise nice simple 00597 // algorithm is the fact that arraytypes have sizes that differentiates types, 00598 // and that function types can be varargs or not. Consider this now. 00599 // 00600 if (const PointerType *PTy = dyn_cast<PointerType>(Ty)) { 00601 return TypesEqual(PTy->getElementType(), 00602 cast<PointerType>(Ty2)->getElementType(), EqTypes); 00603 } else if (const StructType *STy = dyn_cast<StructType>(Ty)) { 00604 const StructType *STy2 = cast<StructType>(Ty2); 00605 if (STy->getNumElements() != STy2->getNumElements()) return false; 00606 for (unsigned i = 0, e = STy2->getNumElements(); i != e; ++i) 00607 if (!TypesEqual(STy->getElementType(i), STy2->getElementType(i), EqTypes)) 00608 return false; 00609 return true; 00610 } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { 00611 const ArrayType *ATy2 = cast<ArrayType>(Ty2); 00612 return ATy->getNumElements() == ATy2->getNumElements() && 00613 TypesEqual(ATy->getElementType(), ATy2->getElementType(), EqTypes); 00614 } else if (const PackedType *PTy = dyn_cast<PackedType>(Ty)) { 00615 const PackedType *PTy2 = cast<PackedType>(Ty2); 00616 return PTy->getNumElements() == PTy2->getNumElements() && 00617 TypesEqual(PTy->getElementType(), PTy2->getElementType(), EqTypes); 00618 } else if (const FunctionType *FTy = dyn_cast<FunctionType>(Ty)) { 00619 const FunctionType *FTy2 = cast<FunctionType>(Ty2); 00620 if (FTy->isVarArg() != FTy2->isVarArg() || 00621 FTy->getNumParams() != FTy2->getNumParams() || 00622 !TypesEqual(FTy->getReturnType(), FTy2->getReturnType(), EqTypes)) 00623 return false; 00624 for (unsigned i = 0, e = FTy2->getNumParams(); i != e; ++i) 00625 if (!TypesEqual(FTy->getParamType(i), FTy2->getParamType(i), EqTypes)) 00626 return false; 00627 return true; 00628 } else { 00629 assert(0 && "Unknown derived type!"); 00630 return false; 00631 } 00632 } 00633 00634 static bool TypesEqual(const Type *Ty, const Type *Ty2) { 00635 std::map<const Type *, const Type *> EqTypes; 00636 return TypesEqual(Ty, Ty2, EqTypes); 00637 } 00638 00639 // AbstractTypeHasCycleThrough - Return true there is a path from CurTy to 00640 // TargetTy in the type graph. We know that Ty is an abstract type, so if we 00641 // ever reach a non-abstract type, we know that we don't need to search the 00642 // subgraph. 00643 static bool AbstractTypeHasCycleThrough(const Type *TargetTy, const Type *CurTy, 00644 std::set<const Type*> &VisitedTypes) { 00645 if (TargetTy == CurTy) return true; 00646 if (!CurTy->isAbstract()) return false; 00647 00648 if (!VisitedTypes.insert(CurTy).second) 00649 return false; // Already been here. 00650 00651 for (Type::subtype_iterator I = CurTy->subtype_begin(), 00652 E = CurTy->subtype_end(); I != E; ++I) 00653 if (AbstractTypeHasCycleThrough(TargetTy, *I, VisitedTypes)) 00654 return true; 00655 return false; 00656 } 00657 00658 static bool ConcreteTypeHasCycleThrough(const Type *TargetTy, const Type *CurTy, 00659 std::set<const Type*> &VisitedTypes) { 00660 if (TargetTy == CurTy) return true; 00661 00662 if (!VisitedTypes.insert(CurTy).second) 00663 return false; // Already been here. 00664 00665 for (Type::subtype_iterator I = CurTy->subtype_begin(), 00666 E = CurTy->subtype_end(); I != E; ++I) 00667 if (ConcreteTypeHasCycleThrough(TargetTy, *I, VisitedTypes)) 00668 return true; 00669 return false; 00670 } 00671 00672 /// TypeHasCycleThroughItself - Return true if the specified type has a cycle 00673 /// back to itself. 00674 static bool TypeHasCycleThroughItself(const Type *Ty) { 00675 std::set<const Type*> VisitedTypes; 00676 00677 if (Ty->isAbstract()) { // Optimized case for abstract types. 00678 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); 00679 I != E; ++I) 00680 if (AbstractTypeHasCycleThrough(Ty, *I, VisitedTypes)) 00681 return true; 00682 } else { 00683 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); 00684 I != E; ++I) 00685 if (ConcreteTypeHasCycleThrough(Ty, *I, VisitedTypes)) 00686 return true; 00687 } 00688 return false; 00689 } 00690 00691 /// getSubElementHash - Generate a hash value for all of the SubType's of this 00692 /// type. The hash value is guaranteed to be zero if any of the subtypes are 00693 /// an opaque type. Otherwise we try to mix them in as well as possible, but do 00694 /// not look at the subtype's subtype's. 00695 static unsigned getSubElementHash(const Type *Ty) { 00696 unsigned HashVal = 0; 00697 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); 00698 I != E; ++I) { 00699 HashVal *= 32; 00700 const Type *SubTy = I->get(); 00701 HashVal += SubTy->getTypeID(); 00702 switch (SubTy->getTypeID()) { 00703 default: break; 00704 case Type::OpaqueTyID: return 0; // Opaque -> hash = 0 no matter what. 00705 case Type::FunctionTyID: 00706 HashVal ^= cast<FunctionType>(SubTy)->getNumParams()*2 + 00707 cast<FunctionType>(SubTy)->isVarArg(); 00708 break; 00709 case Type::ArrayTyID: 00710 HashVal ^= cast<ArrayType>(SubTy)->getNumElements(); 00711 break; 00712 case Type::PackedTyID: 00713 HashVal ^= cast<PackedType>(SubTy)->getNumElements(); 00714 break; 00715 case Type::StructTyID: 00716 HashVal ^= cast<StructType>(SubTy)->getNumElements(); 00717 break; 00718 } 00719 } 00720 return HashVal ? HashVal : 1; // Do not return zero unless opaque subty. 00721 } 00722 00723 //===----------------------------------------------------------------------===// 00724 // Derived Type Factory Functions 00725 //===----------------------------------------------------------------------===// 00726 00727 namespace llvm { 00728 class TypeMapBase { 00729 protected: 00730 /// TypesByHash - Keep track of types by their structure hash value. Note 00731 /// that we only keep track of types that have cycles through themselves in 00732 /// this map. 00733 /// 00734 std::multimap<unsigned, PATypeHolder> TypesByHash; 00735 00736 public: 00737 void RemoveFromTypesByHash(unsigned Hash, const Type *Ty) { 00738 std::multimap<unsigned, PATypeHolder>::iterator I = 00739 TypesByHash.lower_bound(Hash); 00740 for (; I != TypesByHash.end() && I->first == Hash; ++I) { 00741 if (I->second == Ty) { 00742 TypesByHash.erase(I); 00743 return; 00744 } 00745 } 00746 00747 // This must be do to an opaque type that was resolved. Switch down to hash 00748 // code of zero. 00749 assert(Hash && "Didn't find type entry!"); 00750 RemoveFromTypesByHash(0, Ty); 00751 } 00752 00753 /// TypeBecameConcrete - When Ty gets a notification that TheType just became 00754 /// concrete, drop uses and make Ty non-abstract if we should. 00755 void TypeBecameConcrete(DerivedType *Ty, const DerivedType *TheType) { 00756 // If the element just became concrete, remove 'ty' from the abstract 00757 // type user list for the type. Do this for as many times as Ty uses 00758 // OldType. 00759 for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); 00760 I != E; ++I) 00761 if (I->get() == TheType) 00762 TheType->removeAbstractTypeUser(Ty); 00763 00764 // If the type is currently thought to be abstract, rescan all of our 00765 // subtypes to see if the type has just become concrete! Note that this 00766 // may send out notifications to AbstractTypeUsers that types become 00767 // concrete. 00768 if (Ty->isAbstract()) 00769 Ty->PromoteAbstractToConcrete(); 00770 } 00771 }; 00772 } 00773 00774 00775 // TypeMap - Make sure that only one instance of a particular type may be 00776 // created on any given run of the compiler... note that this involves updating 00777 // our map if an abstract type gets refined somehow. 00778 // 00779 namespace llvm { 00780 template<class ValType, class TypeClass> 00781 class TypeMap : public TypeMapBase { 00782 std::map<ValType, PATypeHolder> Map; 00783 public: 00784 typedef typename std::map<ValType, PATypeHolder>::iterator iterator; 00785 ~TypeMap() { print("ON EXIT"); } 00786 00787 inline TypeClass *get(const ValType &V) { 00788 iterator I = Map.find(V); 00789 return I != Map.end() ? cast<TypeClass>((Type*)I->second.get()) : 0; 00790 } 00791 00792 inline void add(const ValType &V, TypeClass *Ty) { 00793 Map.insert(std::make_pair(V, Ty)); 00794 00795 // If this type has a cycle, remember it. 00796 TypesByHash.insert(std::make_pair(ValType::hashTypeStructure(Ty), Ty)); 00797 print("add"); 00798 } 00799 00800 void clear(std::vector<Type *> &DerivedTypes) { 00801 for (typename std::map<ValType, PATypeHolder>::iterator I = Map.begin(), 00802 E = Map.end(); I != E; ++I) 00803 DerivedTypes.push_back(I->second.get()); 00804 TypesByHash.clear(); 00805 Map.clear(); 00806 } 00807 00808 /// RefineAbstractType - This method is called after we have merged a type 00809 /// with another one. We must now either merge the type away with 00810 /// some other type or reinstall it in the map with it's new configuration. 00811 void RefineAbstractType(TypeClass *Ty, const DerivedType *OldType, 00812 const Type *NewType) { 00813 #ifdef DEBUG_MERGE_TYPES 00814 std::cerr << "RefineAbstractType(" << (void*)OldType << "[" << *OldType 00815 << "], " << (void*)NewType << " [" << *NewType << "])\n"; 00816 #endif 00817 00818 // Otherwise, we are changing one subelement type into another. Clearly the 00819 // OldType must have been abstract, making us abstract. 00820 assert(Ty->isAbstract() && "Refining a non-abstract type!"); 00821 assert(OldType != NewType); 00822 00823 // Make a temporary type holder for the type so that it doesn't disappear on 00824 // us when we erase the entry from the map. 00825 PATypeHolder TyHolder = Ty; 00826 00827 // The old record is now out-of-date, because one of the children has been 00828 // updated. Remove the obsolete entry from the map. 00829 unsigned NumErased = Map.erase(ValType::get(Ty)); 00830 assert(NumErased && "Element not found!"); 00831 00832 // Remember the structural hash for the type before we start hacking on it, 00833 // in case we need it later. 00834 unsigned OldTypeHash = ValType::hashTypeStructure(Ty); 00835 00836 // Find the type element we are refining... and change it now! 00837 for (unsigned i = 0, e = Ty->ContainedTys.size(); i != e; ++i) 00838 if (Ty->ContainedTys[i] == OldType) 00839 Ty->ContainedTys[i] = NewType; 00840 unsigned NewTypeHash = ValType::hashTypeStructure(Ty); 00841 00842 // If there are no cycles going through this node, we can do a simple, 00843 // efficient lookup in the map, instead of an inefficient nasty linear 00844 // lookup. 00845 if (!TypeHasCycleThroughItself(Ty)) { 00846 typename std::map<ValType, PATypeHolder>::iterator I; 00847 bool Inserted; 00848 00849 tie(I, Inserted) = Map.insert(std::make_pair(ValType::get(Ty), Ty)); 00850 if (!Inserted) { 00851 // Refined to a different type altogether? 00852 RemoveFromTypesByHash(OldTypeHash, Ty); 00853 00854 // We already have this type in the table. Get rid of the newly refined 00855 // type. 00856 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get()); 00857 Ty->refineAbstractTypeTo(NewTy); 00858 return; 00859 } 00860 } else { 00861 // Now we check to see if there is an existing entry in the table which is 00862 // structurally identical to the newly refined type. If so, this type 00863 // gets refined to the pre-existing type. 00864 // 00865 std::multimap<unsigned, PATypeHolder>::iterator I, E, Entry; 00866 tie(I, E) = TypesByHash.equal_range(NewTypeHash); 00867 Entry = E; 00868 for (; I != E; ++I) { 00869 if (I->second == Ty) { 00870 // Remember the position of the old type if we see it in our scan. 00871 Entry = I; 00872 } else { 00873 if (TypesEqual(Ty, I->second)) { 00874 TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get()); 00875 00876 // Remove the old entry form TypesByHash. If the hash values differ 00877 // now, remove it from the old place. Otherwise, continue scanning 00878 // withing this hashcode to reduce work. 00879 if (NewTypeHash != OldTypeHash) { 00880 RemoveFromTypesByHash(OldTypeHash, Ty); 00881 } else { 00882 if (Entry == E) { 00883 // Find the location of Ty in the TypesByHash structure if we 00884 // haven't seen it already. 00885 while (I->second != Ty) { 00886 ++I; 00887 assert(I != E && "Structure doesn't contain type??"); 00888 } 00889 Entry = I; 00890 } 00891 TypesByHash.erase(Entry); 00892 } 00893 Ty->refineAbstractTypeTo(NewTy); 00894 return; 00895 } 00896 } 00897 } 00898 00899 // If there is no existing type of the same structure, we reinsert an 00900 // updated record into the map. 00901 Map.insert(std::make_pair(ValType::get(Ty), Ty)); 00902 } 00903 00904 // If the hash codes differ, update TypesByHash 00905 if (NewTypeHash != OldTypeHash) { 00906 RemoveFromTypesByHash(OldTypeHash, Ty); 00907 TypesByHash.insert(std::make_pair(NewTypeHash, Ty)); 00908 } 00909 00910 // If the type is currently thought to be abstract, rescan all of our 00911 // subtypes to see if the type has just become concrete! Note that this 00912 // may send out notifications to AbstractTypeUsers that types become 00913 // concrete. 00914 if (Ty->isAbstract()) 00915 Ty->PromoteAbstractToConcrete(); 00916 } 00917 00918 void print(const char *Arg) const { 00919 #ifdef DEBUG_MERGE_TYPES 00920 std::cerr << "TypeMap<>::" << Arg << " table contents:\n"; 00921 unsigned i = 0; 00922 for (typename std::map<ValType, PATypeHolder>::const_iterator I 00923 = Map.begin(), E = Map.end(); I != E; ++I) 00924 std::cerr << " " << (++i) << ". " << (void*)I->second.get() << " " 00925 << *I->second.get() << "\n"; 00926 #endif 00927 } 00928 00929 void dump() const { print("dump output"); } 00930 }; 00931 } 00932 00933 00934 //===----------------------------------------------------------------------===// 00935 // Function Type Factory and Value Class... 00936 // 00937 00938 // FunctionValType - Define a class to hold the key that goes into the TypeMap 00939 // 00940 namespace llvm { 00941 class FunctionValType { 00942 const Type *RetTy; 00943 std::vector<const Type*> ArgTypes; 00944 bool isVarArg; 00945 public: 00946 FunctionValType(const Type *ret, const std::vector<const Type*> &args, 00947 bool IVA) : RetTy(ret), isVarArg(IVA) { 00948 for (unsigned i = 0; i < args.size(); ++i) 00949 ArgTypes.push_back(args[i]); 00950 } 00951 00952 static FunctionValType get(const FunctionType *FT); 00953 00954 static unsigned hashTypeStructure(const FunctionType *FT) { 00955 return FT->getNumParams()*2+FT->isVarArg(); 00956 } 00957 00958 // Subclass should override this... to update self as usual 00959 void doRefinement(const DerivedType *OldType, const Type *NewType) { 00960 if (RetTy == OldType) RetTy = NewType; 00961 for (unsigned i = 0, e = ArgTypes.size(); i != e; ++i) 00962 if (ArgTypes[i] == OldType) ArgTypes[i] = NewType; 00963 } 00964 00965 inline bool operator<(const FunctionValType &MTV) const { 00966 if (RetTy < MTV.RetTy) return true; 00967 if (RetTy > MTV.RetTy) return false; 00968 00969 if (ArgTypes < MTV.ArgTypes) return true; 00970 return ArgTypes == MTV.ArgTypes && isVarArg < MTV.isVarArg; 00971 } 00972 }; 00973 } 00974 00975 // Define the actual map itself now... 00976 static TypeMap<FunctionValType, FunctionType> FunctionTypes; 00977 00978 FunctionValType FunctionValType::get(const FunctionType *FT) { 00979 // Build up a FunctionValType 00980 std::vector<const Type *> ParamTypes; 00981 ParamTypes.reserve(FT->getNumParams()); 00982 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) 00983 ParamTypes.push_back(FT->getParamType(i)); 00984 return FunctionValType(FT->getReturnType(), ParamTypes, FT->isVarArg()); 00985 } 00986 00987 00988 // FunctionType::get - The factory function for the FunctionType class... 00989 FunctionType *FunctionType::get(const Type *ReturnType, 00990 const std::vector<const Type*> &Params, 00991 bool isVarArg) { 00992 FunctionValType VT(ReturnType, Params, isVarArg); 00993 FunctionType *MT = FunctionTypes.get(VT); 00994 if (MT) return MT; 00995 00996 FunctionTypes.add(VT, MT = new FunctionType(ReturnType, Params, isVarArg)); 00997 00998 #ifdef DEBUG_MERGE_TYPES 00999 std::cerr << "Derived new type: " << MT << "\n"; 01000 #endif 01001 return MT; 01002 } 01003 01004 //===----------------------------------------------------------------------===// 01005 // Array Type Factory... 01006 // 01007 namespace llvm { 01008 class ArrayValType { 01009 const Type *ValTy; 01010 uint64_t Size; 01011 public: 01012 ArrayValType(const Type *val, uint64_t sz) : ValTy(val), Size(sz) {} 01013 01014 static ArrayValType get(const ArrayType *AT) { 01015 return ArrayValType(AT->getElementType(), AT->getNumElements()); 01016 } 01017 01018 static unsigned hashTypeStructure(const ArrayType *AT) { 01019 return (unsigned)AT->getNumElements(); 01020 } 01021 01022 // Subclass should override this... to update self as usual 01023 void doRefinement(const DerivedType *OldType, const Type *NewType) { 01024 assert(ValTy == OldType); 01025 ValTy = NewType; 01026 } 01027 01028 inline bool operator<(const ArrayValType &MTV) const { 01029 if (Size < MTV.Size) return true; 01030 return Size == MTV.Size && ValTy < MTV.ValTy; 01031 } 01032 }; 01033 } 01034 static TypeMap<ArrayValType, ArrayType> ArrayTypes; 01035 01036 01037 ArrayType *ArrayType::get(const Type *ElementType, uint64_t NumElements) { 01038 assert(ElementType && "Can't get array of null types!"); 01039 01040 ArrayValType AVT(ElementType, NumElements); 01041 ArrayType *AT = ArrayTypes.get(AVT); 01042 if (AT) return AT; // Found a match, return it! 01043 01044 // Value not found. Derive a new type! 01045 ArrayTypes.add(AVT, AT = new ArrayType(ElementType, NumElements)); 01046 01047 #ifdef DEBUG_MERGE_TYPES 01048 std::cerr << "Derived new type: " << *AT << "\n"; 01049 #endif 01050 return AT; 01051 } 01052 01053 01054 //===----------------------------------------------------------------------===// 01055 // Packed Type Factory... 01056 // 01057 namespace llvm { 01058 class PackedValType { 01059 const Type *ValTy; 01060 unsigned Size; 01061 public: 01062 PackedValType(const Type *val, int sz) : ValTy(val), Size(sz) {} 01063 01064 static PackedValType get(const PackedType *PT) { 01065 return PackedValType(PT->getElementType(), PT->getNumElements()); 01066 } 01067 01068 static unsigned hashTypeStructure(const PackedType *PT) { 01069 return PT->getNumElements(); 01070 } 01071 01072 // Subclass should override this... to update self as usual 01073 void doRefinement(const DerivedType *OldType, const Type *NewType) { 01074 assert(ValTy == OldType); 01075 ValTy = NewType; 01076 } 01077 01078 inline bool operator<(const PackedValType &MTV) const { 01079 if (Size < MTV.Size) return true; 01080 return Size == MTV.Size && ValTy < MTV.ValTy; 01081 } 01082 }; 01083 } 01084 static TypeMap<PackedValType, PackedType> PackedTypes; 01085 01086 01087 PackedType *PackedType::get(const Type *ElementType, unsigned NumElements) { 01088 assert(ElementType && "Can't get packed of null types!"); 01089 assert(isPowerOf2_32(NumElements) && "Vector length should be a power of 2!"); 01090 01091 PackedValType PVT(ElementType, NumElements); 01092 PackedType *PT = PackedTypes.get(PVT); 01093 if (PT) return PT; // Found a match, return it! 01094 01095 // Value not found. Derive a new type! 01096 PackedTypes.add(PVT, PT = new PackedType(ElementType, NumElements)); 01097 01098 #ifdef DEBUG_MERGE_TYPES 01099 std::cerr << "Derived new type: " << *PT << "\n"; 01100 #endif 01101 return PT; 01102 } 01103 01104 //===----------------------------------------------------------------------===// 01105 // Struct Type Factory... 01106 // 01107 01108 namespace llvm { 01109 // StructValType - Define a class to hold the key that goes into the TypeMap 01110 // 01111 class StructValType { 01112 std::vector<const Type*> ElTypes; 01113 public: 01114 StructValType(const std::vector<const Type*> &args) : ElTypes(args) {} 01115 01116 static StructValType get(const StructType *ST) { 01117 std::vector<const Type *> ElTypes; 01118 ElTypes.reserve(ST->getNumElements()); 01119 for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) 01120 ElTypes.push_back(ST->getElementType(i)); 01121 01122 return StructValType(ElTypes); 01123 } 01124 01125 static unsigned hashTypeStructure(const StructType *ST) { 01126 return ST->getNumElements(); 01127 } 01128 01129 // Subclass should override this... to update self as usual 01130 void doRefinement(const DerivedType *OldType, const Type *NewType) { 01131 for (unsigned i = 0; i < ElTypes.size(); ++i) 01132 if (ElTypes[i] == OldType) ElTypes[i] = NewType; 01133 } 01134 01135 inline bool operator<(const StructValType &STV) const { 01136 return ElTypes < STV.ElTypes; 01137 } 01138 }; 01139 } 01140 01141 static TypeMap<StructValType, StructType> StructTypes; 01142 01143 StructType *StructType::get(const std::vector<const Type*> &ETypes) { 01144 StructValType STV(ETypes); 01145 StructType *ST = StructTypes.get(STV); 01146 if (ST) return ST; 01147 01148 // Value not found. Derive a new type! 01149 StructTypes.add(STV, ST = new StructType(ETypes)); 01150 01151 #ifdef DEBUG_MERGE_TYPES 01152 std::cerr << "Derived new type: " << *ST << "\n"; 01153 #endif 01154 return ST; 01155 } 01156 01157 01158 01159 //===----------------------------------------------------------------------===// 01160 // Pointer Type Factory... 01161 // 01162 01163 // PointerValType - Define a class to hold the key that goes into the TypeMap 01164 // 01165 namespace llvm { 01166 class PointerValType { 01167 const Type *ValTy; 01168 public: 01169 PointerValType(const Type *val) : ValTy(val) {} 01170 01171 static PointerValType get(const PointerType *PT) { 01172 return PointerValType(PT->getElementType()); 01173 } 01174 01175 static unsigned hashTypeStructure(const PointerType *PT) { 01176 return getSubElementHash(PT); 01177 } 01178 01179 // Subclass should override this... to update self as usual 01180 void doRefinement(const DerivedType *OldType, const Type *NewType) { 01181 assert(ValTy == OldType); 01182 ValTy = NewType; 01183 } 01184 01185 bool operator<(const PointerValType &MTV) const { 01186 return ValTy < MTV.ValTy; 01187 } 01188 }; 01189 } 01190 01191 static TypeMap<PointerValType, PointerType> PointerTypes; 01192 01193 PointerType *PointerType::get(const Type *ValueType) { 01194 assert(ValueType && "Can't get a pointer to <null> type!"); 01195 // FIXME: The sparc backend makes void pointers, which is horribly broken. 01196 // "Fix" it, then reenable this assertion. 01197 //assert(ValueType != Type::VoidTy && 01198 // "Pointer to void is not valid, use sbyte* instead!"); 01199 PointerValType PVT(ValueType); 01200 01201 PointerType *PT = PointerTypes.get(PVT); 01202 if (PT) return PT; 01203 01204 // Value not found. Derive a new type! 01205 PointerTypes.add(PVT, PT = new PointerType(ValueType)); 01206 01207 #ifdef DEBUG_MERGE_TYPES 01208 std::cerr << "Derived new type: " << *PT << "\n"; 01209 #endif 01210 return PT; 01211 } 01212 01213 //===----------------------------------------------------------------------===// 01214 // Derived Type Refinement Functions 01215 //===----------------------------------------------------------------------===// 01216 01217 // removeAbstractTypeUser - Notify an abstract type that a user of the class 01218 // no longer has a handle to the type. This function is called primarily by 01219 // the PATypeHandle class. When there are no users of the abstract type, it 01220 // is annihilated, because there is no way to get a reference to it ever again. 01221 // 01222 void Type::removeAbstractTypeUser(AbstractTypeUser *U) const { 01223 // Search from back to front because we will notify users from back to 01224 // front. Also, it is likely that there will be a stack like behavior to 01225 // users that register and unregister users. 01226 // 01227 unsigned i; 01228 for (i = AbstractTypeUsers.size(); AbstractTypeUsers[i-1] != U; --i) 01229 assert(i != 0 && "AbstractTypeUser not in user list!"); 01230 01231 --i; // Convert to be in range 0 <= i < size() 01232 assert(i < AbstractTypeUsers.size() && "Index out of range!"); // Wraparound? 01233 01234 AbstractTypeUsers.erase(AbstractTypeUsers.begin()+i); 01235 01236 #ifdef DEBUG_MERGE_TYPES 01237 std::cerr << " remAbstractTypeUser[" << (void*)this << ", " 01238 << *this << "][" << i << "] User = " << U << "\n"; 01239 #endif 01240 01241 if (AbstractTypeUsers.empty() && getRefCount() == 0 && isAbstract()) { 01242 #ifdef DEBUG_MERGE_TYPES 01243 std::cerr << "DELETEing unused abstract type: <" << *this 01244 << ">[" << (void*)this << "]" << "\n"; 01245 #endif 01246 delete this; // No users of this abstract type! 01247 } 01248 } 01249 01250 01251 // refineAbstractTypeTo - This function is used to when it is discovered that 01252 // the 'this' abstract type is actually equivalent to the NewType specified. 01253 // This causes all users of 'this' to switch to reference the more concrete type 01254 // NewType and for 'this' to be deleted. 01255 // 01256 void DerivedType::refineAbstractTypeTo(const Type *NewType) { 01257 assert(isAbstract() && "refineAbstractTypeTo: Current type is not abstract!"); 01258 assert(this != NewType && "Can't refine to myself!"); 01259 assert(ForwardType == 0 && "This type has already been refined!"); 01260 01261 // The descriptions may be out of date. Conservatively clear them all! 01262 AbstractTypeDescriptions.clear(); 01263 01264 #ifdef DEBUG_MERGE_TYPES 01265 std::cerr << "REFINING abstract type [" << (void*)this << " " 01266 << *this << "] to [" << (void*)NewType << " " 01267 << *NewType << "]!\n"; 01268 #endif 01269 01270 // Make sure to put the type to be refined to into a holder so that if IT gets 01271 // refined, that we will not continue using a dead reference... 01272 // 01273 PATypeHolder NewTy(NewType); 01274 01275 // Any PATypeHolders referring to this type will now automatically forward to 01276 // the type we are resolved to. 01277 ForwardType = NewType; 01278 if (NewType->isAbstract()) 01279 cast<DerivedType>(NewType)->addRef(); 01280 01281 // Add a self use of the current type so that we don't delete ourself until 01282 // after the function exits. 01283 // 01284 PATypeHolder CurrentTy(this); 01285 01286 // To make the situation simpler, we ask the subclass to remove this type from 01287 // the type map, and to replace any type uses with uses of non-abstract types. 01288 // This dramatically limits the amount of recursive type trouble we can find 01289 // ourselves in. 01290 dropAllTypeUses(); 01291 01292 // Iterate over all of the uses of this type, invoking callback. Each user 01293 // should remove itself from our use list automatically. We have to check to 01294 // make sure that NewTy doesn't _become_ 'this'. If it does, resolving types 01295 // will not cause users to drop off of the use list. If we resolve to ourself 01296 // we succeed! 01297 // 01298 while (!AbstractTypeUsers.empty() && NewTy != this) { 01299 AbstractTypeUser *User = AbstractTypeUsers.back(); 01300 01301 unsigned OldSize = AbstractTypeUsers.size(); 01302 #ifdef DEBUG_MERGE_TYPES 01303 std::cerr << " REFINING user " << OldSize-1 << "[" << (void*)User 01304 << "] of abstract type [" << (void*)this << " " 01305 << *this << "] to [" << (void*)NewTy.get() << " " 01306 << *NewTy << "]!\n"; 01307 #endif 01308 User->refineAbstractType(this, NewTy); 01309 01310 assert(AbstractTypeUsers.size() != OldSize && 01311 "AbsTyUser did not remove self from user list!"); 01312 } 01313 01314 // If we were successful removing all users from the type, 'this' will be 01315 // deleted when the last PATypeHolder is destroyed or updated from this type. 01316 // This may occur on exit of this function, as the CurrentTy object is 01317 // destroyed. 01318 } 01319 01320 // notifyUsesThatTypeBecameConcrete - Notify AbstractTypeUsers of this type that 01321 // the current type has transitioned from being abstract to being concrete. 01322 // 01323 void DerivedType::notifyUsesThatTypeBecameConcrete() { 01324 #ifdef DEBUG_MERGE_TYPES 01325 std::cerr << "typeIsREFINED type: " << (void*)this << " " << *this << "\n"; 01326 #endif 01327 01328 unsigned OldSize = AbstractTypeUsers.size(); 01329 while (!AbstractTypeUsers.empty()) { 01330 AbstractTypeUser *ATU = AbstractTypeUsers.back(); 01331 ATU->typeBecameConcrete(this); 01332 01333 assert(AbstractTypeUsers.size() < OldSize-- && 01334 "AbstractTypeUser did not remove itself from the use list!"); 01335 } 01336 } 01337 01338 // refineAbstractType - Called when a contained type is found to be more 01339 // concrete - this could potentially change us from an abstract type to a 01340 // concrete type. 01341 // 01342 void FunctionType::refineAbstractType(const DerivedType *OldType, 01343 const Type *NewType) { 01344 FunctionTypes.RefineAbstractType(this, OldType, NewType); 01345 } 01346 01347 void FunctionType::typeBecameConcrete(const DerivedType *AbsTy) { 01348 FunctionTypes.TypeBecameConcrete(this, AbsTy); 01349 } 01350 01351 01352 // refineAbstractType - Called when a contained type is found to be more 01353 // concrete - this could potentially change us from an abstract type to a 01354 // concrete type. 01355 // 01356 void ArrayType::refineAbstractType(const DerivedType *OldType, 01357 const Type *NewType) { 01358 ArrayTypes.RefineAbstractType(this, OldType, NewType); 01359 } 01360 01361 void ArrayType::typeBecameConcrete(const DerivedType *AbsTy) { 01362 ArrayTypes.TypeBecameConcrete(this, AbsTy); 01363 } 01364 01365 // refineAbstractType - Called when a contained type is found to be more 01366 // concrete - this could potentially change us from an abstract type to a 01367 // concrete type. 01368 // 01369 void PackedType::refineAbstractType(const DerivedType *OldType, 01370 const Type *NewType) { 01371 PackedTypes.RefineAbstractType(this, OldType, NewType); 01372 } 01373 01374 void PackedType::typeBecameConcrete(const DerivedType *AbsTy) { 01375 PackedTypes.TypeBecameConcrete(this, AbsTy); 01376 } 01377 01378 // refineAbstractType - Called when a contained type is found to be more 01379 // concrete - this could potentially change us from an abstract type to a 01380 // concrete type. 01381 // 01382 void StructType::refineAbstractType(const DerivedType *OldType, 01383 const Type *NewType) { 01384 StructTypes.RefineAbstractType(this, OldType, NewType); 01385 } 01386 01387 void StructType::typeBecameConcrete(const DerivedType *AbsTy) { 01388 StructTypes.TypeBecameConcrete(this, AbsTy); 01389 } 01390 01391 // refineAbstractType - Called when a contained type is found to be more 01392 // concrete - this could potentially change us from an abstract type to a 01393 // concrete type. 01394 // 01395 void PointerType::refineAbstractType(const DerivedType *OldType, 01396 const Type *NewType) { 01397 PointerTypes.RefineAbstractType(this, OldType, NewType); 01398 } 01399 01400 void PointerType::typeBecameConcrete(const DerivedType *AbsTy) { 01401 PointerTypes.TypeBecameConcrete(this, AbsTy); 01402 } 01403 01404 bool SequentialType::indexValid(const Value *V) const { 01405 const Type *Ty = V->getType(); 01406 switch (Ty->getTypeID()) { 01407 case Type::IntTyID: 01408 case Type::UIntTyID: 01409 case Type::LongTyID: 01410 case Type::ULongTyID: 01411 return true; 01412 default: 01413 return false; 01414 } 01415 } 01416 01417 namespace llvm { 01418 std::ostream &operator<<(std::ostream &OS, const Type *T) { 01419 if (T == 0) 01420 OS << "<null> value!\n"; 01421 else 01422 T->print(OS); 01423 return OS; 01424 } 01425 01426 std::ostream &operator<<(std::ostream &OS, const Type &T) { 01427 T.print(OS); 01428 return OS; 01429 } 01430 } 01431 01432 /// clearAllTypeMaps - This method frees all internal memory used by the 01433 /// type subsystem, which can be used in environments where this memory is 01434 /// otherwise reported as a leak. 01435 void Type::clearAllTypeMaps() { 01436 std::vector<Type *> DerivedTypes; 01437 01438 FunctionTypes.clear(DerivedTypes); 01439 PointerTypes.clear(DerivedTypes); 01440 StructTypes.clear(DerivedTypes); 01441 ArrayTypes.clear(DerivedTypes); 01442 PackedTypes.clear(DerivedTypes); 01443 01444 for(std::vector<Type *>::iterator I = DerivedTypes.begin(), 01445 E = DerivedTypes.end(); I != E; ++I) 01446 (*I)->ContainedTys.clear(); 01447 for(std::vector<Type *>::iterator I = DerivedTypes.begin(), 01448 E = DerivedTypes.end(); I != E; ++I) 01449 delete *I; 01450 DerivedTypes.clear(); 01451 } 01452 01453 // vim: sw=2