diff options
Diffstat (limited to 'lib/VMCore/TypesContext.h')
| -rw-r--r-- | lib/VMCore/TypesContext.h | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/lib/VMCore/TypesContext.h b/lib/VMCore/TypesContext.h new file mode 100644 index 0000000..e7950bd --- /dev/null +++ b/lib/VMCore/TypesContext.h @@ -0,0 +1,424 @@ +//===-- TypesContext.h - Types-related Context Internals ------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines various helper methods and classes used by +// LLVMContextImpl for creating and managing types. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_TYPESCONTEXT_H +#define LLVM_TYPESCONTEXT_H + +#include "llvm/ADT/STLExtras.h" +#include <map> + + +//===----------------------------------------------------------------------===// +// Derived Type Factory Functions +//===----------------------------------------------------------------------===// +namespace llvm { + +/// getSubElementHash - Generate a hash value for all of the SubType's of this +/// type. The hash value is guaranteed to be zero if any of the subtypes are +/// an opaque type. Otherwise we try to mix them in as well as possible, but do +/// not look at the subtype's subtype's. +static unsigned getSubElementHash(const Type *Ty) { + unsigned HashVal = 0; + for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); + I != E; ++I) { + HashVal *= 32; + const Type *SubTy = I->get(); + HashVal += SubTy->getTypeID(); + switch (SubTy->getTypeID()) { + default: break; + case Type::OpaqueTyID: return 0; // Opaque -> hash = 0 no matter what. + case Type::IntegerTyID: + HashVal ^= (cast<IntegerType>(SubTy)->getBitWidth() << 3); + break; + case Type::FunctionTyID: + HashVal ^= cast<FunctionType>(SubTy)->getNumParams()*2 + + cast<FunctionType>(SubTy)->isVarArg(); + break; + case Type::ArrayTyID: + HashVal ^= cast<ArrayType>(SubTy)->getNumElements(); + break; + case Type::VectorTyID: + HashVal ^= cast<VectorType>(SubTy)->getNumElements(); + break; + case Type::StructTyID: + HashVal ^= cast<StructType>(SubTy)->getNumElements(); + break; + case Type::PointerTyID: + HashVal ^= cast<PointerType>(SubTy)->getAddressSpace(); + break; + } + } + return HashVal ? HashVal : 1; // Do not return zero unless opaque subty. +} + +//===----------------------------------------------------------------------===// +// Integer Type Factory... +// +class IntegerValType { + uint32_t bits; +public: + IntegerValType(uint16_t numbits) : bits(numbits) {} + + static IntegerValType get(const IntegerType *Ty) { + return IntegerValType(Ty->getBitWidth()); + } + + static unsigned hashTypeStructure(const IntegerType *Ty) { + return (unsigned)Ty->getBitWidth(); + } + + inline bool operator<(const IntegerValType &IVT) const { + return bits < IVT.bits; + } +}; + +// PointerValType - Define a class to hold the key that goes into the TypeMap +// +class PointerValType { + const Type *ValTy; + unsigned AddressSpace; +public: + PointerValType(const Type *val, unsigned as) : ValTy(val), AddressSpace(as) {} + + static PointerValType get(const PointerType *PT) { + return PointerValType(PT->getElementType(), PT->getAddressSpace()); + } + + static unsigned hashTypeStructure(const PointerType *PT) { + return getSubElementHash(PT); + } + + bool operator<(const PointerValType &MTV) const { + if (AddressSpace < MTV.AddressSpace) return true; + return AddressSpace == MTV.AddressSpace && ValTy < MTV.ValTy; + } +}; + +//===----------------------------------------------------------------------===// +// Array Type Factory... +// +class ArrayValType { + const Type *ValTy; + uint64_t Size; +public: + ArrayValType(const Type *val, uint64_t sz) : ValTy(val), Size(sz) {} + + static ArrayValType get(const ArrayType *AT) { + return ArrayValType(AT->getElementType(), AT->getNumElements()); + } + + static unsigned hashTypeStructure(const ArrayType *AT) { + return (unsigned)AT->getNumElements(); + } + + inline bool operator<(const ArrayValType &MTV) const { + if (Size < MTV.Size) return true; + return Size == MTV.Size && ValTy < MTV.ValTy; + } +}; + +//===----------------------------------------------------------------------===// +// Vector Type Factory... +// +class VectorValType { + const Type *ValTy; + unsigned Size; +public: + VectorValType(const Type *val, int sz) : ValTy(val), Size(sz) {} + + static VectorValType get(const VectorType *PT) { + return VectorValType(PT->getElementType(), PT->getNumElements()); + } + + static unsigned hashTypeStructure(const VectorType *PT) { + return PT->getNumElements(); + } + + inline bool operator<(const VectorValType &MTV) const { + if (Size < MTV.Size) return true; + return Size == MTV.Size && ValTy < MTV.ValTy; + } +}; + +// StructValType - Define a class to hold the key that goes into the TypeMap +// +class StructValType { + std::vector<const Type*> ElTypes; + bool packed; +public: + StructValType(const std::vector<const Type*> &args, bool isPacked) + : ElTypes(args), packed(isPacked) {} + + static StructValType get(const StructType *ST) { + std::vector<const Type *> ElTypes; + ElTypes.reserve(ST->getNumElements()); + for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) + ElTypes.push_back(ST->getElementType(i)); + + return StructValType(ElTypes, ST->isPacked()); + } + + static unsigned hashTypeStructure(const StructType *ST) { + return ST->getNumElements(); + } + + inline bool operator<(const StructValType &STV) const { + if (ElTypes < STV.ElTypes) return true; + else if (ElTypes > STV.ElTypes) return false; + else return (int)packed < (int)STV.packed; + } +}; + +// FunctionValType - Define a class to hold the key that goes into the TypeMap +// +class FunctionValType { + const Type *RetTy; + std::vector<const Type*> ArgTypes; + bool isVarArg; +public: + FunctionValType(const Type *ret, const std::vector<const Type*> &args, + bool isVA) : RetTy(ret), ArgTypes(args), isVarArg(isVA) {} + + static FunctionValType get(const FunctionType *FT); + + static unsigned hashTypeStructure(const FunctionType *FT) { + unsigned Result = FT->getNumParams()*2 + FT->isVarArg(); + return Result; + } + + inline bool operator<(const FunctionValType &MTV) const { + if (RetTy < MTV.RetTy) return true; + if (RetTy > MTV.RetTy) return false; + if (isVarArg < MTV.isVarArg) return true; + if (isVarArg > MTV.isVarArg) return false; + if (ArgTypes < MTV.ArgTypes) return true; + if (ArgTypes > MTV.ArgTypes) return false; + return false; + } +}; + +class TypeMapBase { +protected: + /// TypesByHash - Keep track of types by their structure hash value. Note + /// that we only keep track of types that have cycles through themselves in + /// this map. + /// + std::multimap<unsigned, PATypeHolder> TypesByHash; + +public: + ~TypeMapBase() { + // PATypeHolder won't destroy non-abstract types. + // We can't destroy them by simply iterating, because + // they may contain references to each-other. + for (std::multimap<unsigned, PATypeHolder>::iterator I + = TypesByHash.begin(), E = TypesByHash.end(); I != E; ++I) { + Type *Ty = const_cast<Type*>(I->second.Ty); + I->second.destroy(); + // We can't invoke destroy or delete, because the type may + // contain references to already freed types. + // So we have to destruct the object the ugly way. + if (Ty) { + Ty->AbstractTypeUsers.clear(); + static_cast<const Type*>(Ty)->Type::~Type(); + operator delete(Ty); + } + } + } + + void RemoveFromTypesByHash(unsigned Hash, const Type *Ty) { + std::multimap<unsigned, PATypeHolder>::iterator I = + TypesByHash.lower_bound(Hash); + for (; I != TypesByHash.end() && I->first == Hash; ++I) { + if (I->second == Ty) { + TypesByHash.erase(I); + return; + } + } + + // This must be do to an opaque type that was resolved. Switch down to hash + // code of zero. + assert(Hash && "Didn't find type entry!"); + RemoveFromTypesByHash(0, Ty); + } + + /// TypeBecameConcrete - When Ty gets a notification that TheType just became + /// concrete, drop uses and make Ty non-abstract if we should. + void TypeBecameConcrete(DerivedType *Ty, const DerivedType *TheType) { + // If the element just became concrete, remove 'ty' from the abstract + // type user list for the type. Do this for as many times as Ty uses + // OldType. + for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end(); + I != E; ++I) + if (I->get() == TheType) + TheType->removeAbstractTypeUser(Ty); + + // If the type is currently thought to be abstract, rescan all of our + // subtypes to see if the type has just become concrete! Note that this + // may send out notifications to AbstractTypeUsers that types become + // concrete. + if (Ty->isAbstract()) + Ty->PromoteAbstractToConcrete(); + } +}; + +// TypeMap - Make sure that only one instance of a particular type may be +// created on any given run of the compiler... note that this involves updating +// our map if an abstract type gets refined somehow. +// +template<class ValType, class TypeClass> +class TypeMap : public TypeMapBase { + std::map<ValType, PATypeHolder> Map; +public: + typedef typename std::map<ValType, PATypeHolder>::iterator iterator; + ~TypeMap() { print("ON EXIT"); } + + inline TypeClass *get(const ValType &V) { + iterator I = Map.find(V); + return I != Map.end() ? cast<TypeClass>((Type*)I->second.get()) : 0; + } + + inline void add(const ValType &V, TypeClass *Ty) { + Map.insert(std::make_pair(V, Ty)); + + // If this type has a cycle, remember it. + TypesByHash.insert(std::make_pair(ValType::hashTypeStructure(Ty), Ty)); + print("add"); + } + + /// RefineAbstractType - This method is called after we have merged a type + /// with another one. We must now either merge the type away with + /// some other type or reinstall it in the map with it's new configuration. + void RefineAbstractType(TypeClass *Ty, const DerivedType *OldType, + const Type *NewType) { +#ifdef DEBUG_MERGE_TYPES + DEBUG(errs() << "RefineAbstractType(" << (void*)OldType << "[" << *OldType + << "], " << (void*)NewType << " [" << *NewType << "])\n"); +#endif + + // Otherwise, we are changing one subelement type into another. Clearly the + // OldType must have been abstract, making us abstract. + assert(Ty->isAbstract() && "Refining a non-abstract type!"); + assert(OldType != NewType); + + // Make a temporary type holder for the type so that it doesn't disappear on + // us when we erase the entry from the map. + PATypeHolder TyHolder = Ty; + + // The old record is now out-of-date, because one of the children has been + // updated. Remove the obsolete entry from the map. + unsigned NumErased = Map.erase(ValType::get(Ty)); + assert(NumErased && "Element not found!"); NumErased = NumErased; + + // Remember the structural hash for the type before we start hacking on it, + // in case we need it later. + unsigned OldTypeHash = ValType::hashTypeStructure(Ty); + + // Find the type element we are refining... and change it now! + for (unsigned i = 0, e = Ty->getNumContainedTypes(); i != e; ++i) + if (Ty->ContainedTys[i] == OldType) + Ty->ContainedTys[i] = NewType; + unsigned NewTypeHash = ValType::hashTypeStructure(Ty); + + // If there are no cycles going through this node, we can do a simple, + // efficient lookup in the map, instead of an inefficient nasty linear + // lookup. + if (!TypeHasCycleThroughItself(Ty)) { + typename std::map<ValType, PATypeHolder>::iterator I; + bool Inserted; + + tie(I, Inserted) = Map.insert(std::make_pair(ValType::get(Ty), Ty)); + if (!Inserted) { + // Refined to a different type altogether? + RemoveFromTypesByHash(OldTypeHash, Ty); + + // We already have this type in the table. Get rid of the newly refined + // type. + TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get()); + Ty->unlockedRefineAbstractTypeTo(NewTy); + return; + } + } else { + // Now we check to see if there is an existing entry in the table which is + // structurally identical to the newly refined type. If so, this type + // gets refined to the pre-existing type. + // + std::multimap<unsigned, PATypeHolder>::iterator I, E, Entry; + tie(I, E) = TypesByHash.equal_range(NewTypeHash); + Entry = E; + for (; I != E; ++I) { + if (I->second == Ty) { + // Remember the position of the old type if we see it in our scan. + Entry = I; + } else { + if (TypesEqual(Ty, I->second)) { + TypeClass *NewTy = cast<TypeClass>((Type*)I->second.get()); + + // Remove the old entry form TypesByHash. If the hash values differ + // now, remove it from the old place. Otherwise, continue scanning + // withing this hashcode to reduce work. + if (NewTypeHash != OldTypeHash) { + RemoveFromTypesByHash(OldTypeHash, Ty); + } else { + if (Entry == E) { + // Find the location of Ty in the TypesByHash structure if we + // haven't seen it already. + while (I->second != Ty) { + ++I; + assert(I != E && "Structure doesn't contain type??"); + } + Entry = I; + } + TypesByHash.erase(Entry); + } + Ty->unlockedRefineAbstractTypeTo(NewTy); + return; + } + } + } + + // If there is no existing type of the same structure, we reinsert an + // updated record into the map. + Map.insert(std::make_pair(ValType::get(Ty), Ty)); + } + + // If the hash codes differ, update TypesByHash + if (NewTypeHash != OldTypeHash) { + RemoveFromTypesByHash(OldTypeHash, Ty); + TypesByHash.insert(std::make_pair(NewTypeHash, Ty)); + } + + // If the type is currently thought to be abstract, rescan all of our + // subtypes to see if the type has just become concrete! Note that this + // may send out notifications to AbstractTypeUsers that types become + // concrete. + if (Ty->isAbstract()) + Ty->PromoteAbstractToConcrete(); + } + + void print(const char *Arg) const { +#ifdef DEBUG_MERGE_TYPES + DEBUG(errs() << "TypeMap<>::" << Arg << " table contents:\n"); + unsigned i = 0; + for (typename std::map<ValType, PATypeHolder>::const_iterator I + = Map.begin(), E = Map.end(); I != E; ++I) + DEBUG(errs() << " " << (++i) << ". " << (void*)I->second.get() << " " + << *I->second.get() << "\n"); +#endif + } + + void dump() const { print("dump output"); } +}; +} + +#endif |
