-
-/// 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.
-}
-
-//===----------------------------------------------------------------------===//
-// Derived Type Factory Functions
-//===----------------------------------------------------------------------===//
-
-namespace llvm {
-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:
- 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.
-//
-namespace llvm {
-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
- DOUT << "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->refineAbstractTypeTo(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->refineAbstractTypeTo(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
- DOUT << "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)
- DOUT << " " << (++i) << ". " << (void*)I->second.get() << " "
- << *I->second.get() << "\n";
-#endif
- }
-
- void dump() const { print("dump output"); }
-};