Canonicalize types.

runtime/vm/object.h

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "vm/assert.h"
 #include "vm/dart.h"
 #include "vm/globals.h"
@@ skipping 596 matching lines @@
   void set_signature_function(const Function& value) const;
   void set_signature_type(const Type& value) const;
   void set_class_state(int8_t state) const;
 
   void set_constants(const Array& value) const;
   RawArray* constants() const;
 
   void set_num_constants(intptr_t value) const;
   intptr_t num_constants() const;
 
+  void set_canonical_types(const Array& value) const;
+  RawArray* canonical_types() const;
+
+  void set_num_canonical_types(intptr_t value) const;
+  intptr_t num_canonical_types() const;
+
   void CalculateFieldOffsets() const;
 
   // Check the subtype or assignability relationship.
   bool TestType(TypeTestKind test,
                 const TypeArguments& type_arguments,
                 const Class& other,
                 const TypeArguments& other_type_arguments) const;
 
   // Assigns empty array to all raw class array fields.
   void InitEmptyFields();
 
   HEAP_OBJECT_IMPLEMENTATION(Class, Object);
   friend class Object;
   friend class Instance;
+  friend class ParameterizedType;
 };
 
 
 // Unresolved class is used for storing unresolved names which will be resolved
 // to a class after all classes have been loaded and finalized.
 class UnresolvedClass : public Object {
  public:
   RawString* qualifier() const { return raw_ptr()->qualifier_; }
   RawString* ident() const { return raw_ptr()->ident_; }
   intptr_t token_index() const { return raw_ptr()->token_index_; }
@@ skipping 29 matching lines @@
 class Type : public Object {
  public:
   virtual bool IsFinalized() const;
   virtual bool IsBeingFinalized() const;
   virtual bool IsResolved() const;
   virtual bool HasResolvedTypeClass() const;
   virtual RawClass* type_class() const;
   virtual RawUnresolvedClass* unresolved_class() const;
   virtual RawTypeArguments* arguments() const;
   virtual bool IsInstantiated() const;
+  virtual bool Equals(const Type& other) const;
 
   // Instantiate this type using the given type argument vector starting at the
   // given offset.
   // Return a new type, or return 'this' if it is already instantiated.
   virtual RawType* InstantiateFrom(
       const TypeArguments& instantiator_type_arguments,
       intptr_t offset) const;
 
+  // Return the canonical version of this type.
+  virtual RawType* Canonicalize() const;
+
   // The name of this type, including the names of its type arguments, if any.
   virtual RawString* Name() const;
 
   // The index of this type parameter. Fail if not a type parameter.
   virtual intptr_t Index() const;
 
   // The name of this type's class, i.e. without the type argument names of this
   // type.
   RawString* ClassName() const;
 
@@ skipping 76 matching lines @@
   // The 'num' interface type.
   static RawType* NumberInterface();
 
   // The 'String' interface type.
   static RawType* StringInterface();
 
   // The 'Function' interface type.
   static RawType* FunctionInterface();
 
   // The least specific valid raw type of the given class.
-  // For example, type A<DynamicType> would be returned for class A<T>, and type
-  // B<DynamicType, A<DynamicType>> would be returned for B<U, V extends A>.
+  // For example, type A<Dynamic> would be returned for class A<T>, and type
+  // B<Dynamic, A<Dynamic>> would be returned for B<U, V extends A>.
   static RawType* NewRawType(const Class& type_class);
 
   // The finalized type of the given non-parameterized class.
   static RawType* NewNonParameterizedType(const Class& type_class);
 
   static RawType* NewParameterizedType(const Object& type_class,
                                        const TypeArguments& arguments);
 
   static RawType* NewTypeParameter(intptr_t index, const String& name);
 
@@ skipping 24 matching lines @@
   }
   void set_is_being_finalized() const;
   virtual bool IsResolved() const;  // Class and all arguments classes resolved.
   virtual bool HasResolvedTypeClass() const;  // Own type class resolved.
   virtual RawClass* type_class() const;
   void set_type_class(const Object& value) const;
   virtual RawUnresolvedClass* unresolved_class() const;
   virtual RawTypeArguments* arguments() const;
   void set_arguments(const TypeArguments& value) const;
   virtual bool IsInstantiated() const;
+  virtual bool Equals(const Type& other) const;
   virtual RawType* InstantiateFrom(
       const TypeArguments& instantiator_type_arguments,
       intptr_t offset) const;
+  virtual RawType* Canonicalize() const;
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawParameterizedType));
   }
 
   static RawParameterizedType* New(const Object& clazz,
                                    const TypeArguments& arguments);
 
  private:
   void set_type_state(int8_t state) const;
@@ skipping 12 matching lines @@
 // instantiated yet, i.e. it is only a place holder.
 class TypeParameter : public Type {
  public:
   virtual bool IsFinalized() const { return true; }
   virtual bool IsBeingFinalized() const { return false; }
   virtual bool IsResolved() const { return true; }
   virtual bool HasResolvedTypeClass() const { return false; }
   virtual RawString* Name() const { return raw_ptr()->name_; }
   virtual intptr_t Index() const { return raw_ptr()->index_; }
   virtual bool IsInstantiated() const { return false; }
+  virtual bool Equals(const Type& other) const;
   virtual RawType* InstantiateFrom(
       const TypeArguments& instantiator_type_arguments,
       intptr_t offset) const;
+  virtual RawType* Canonicalize() const { return raw(); }
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawTypeParameter));
   }
 
   static RawTypeParameter* New(intptr_t index, const String& name);
 
  private:
   void set_index(intptr_t value) const;
   void set_name(const String& value) const;
@@ skipping 51 matching lines @@
 // TypeArguments is an abstract superclass.
 // Subclasses of TypeArguments are TypeArray and InstantiatedTypes.
 class TypeArguments : public Object {
  public:
   virtual intptr_t Length() const;
   virtual RawType* TypeAt(intptr_t index) const;
   virtual void SetTypeAt(intptr_t index, const Type& value) const;
   virtual bool IsResolved() const;
   virtual bool IsInstantiated() const;
   virtual bool IsUninstantiatedIdentity() const;
+  virtual bool Equals(const TypeArguments& other) const;
+  static bool AreEqual(const TypeArguments& arguments,
+                       const TypeArguments& other_arguments);
 
   // Return 'this' if this type argument vector is instantiated, i.e. if it does
   // not refer to type parameters. Otherwise, return a new type argument vector
   // where each reference to a type parameter is replaced with the corresponding
   // type of the instantiator type argument vector starting at the given offset.
   virtual RawTypeArguments* InstantiateFrom(
       const TypeArguments& instantiator_type_arguments,
       intptr_t offset) const;
 
   // Check if this type argument vector consists solely of DynamicType,
@@ skipping 18 matching lines @@
 
 // A TypeArray is simply an array of Types.
 class TypeArray : public TypeArguments {
  public:
   virtual intptr_t Length() const;
   virtual RawType* TypeAt(intptr_t index) const;
   virtual void SetTypeAt(intptr_t index, const Type& value) const;
   virtual bool IsResolved() const;
   virtual bool IsInstantiated() const;
   virtual bool IsUninstantiatedIdentity() const;
+  virtual bool Equals(const TypeArguments& other) const;
+
   virtual RawTypeArguments* InstantiateFrom(
       const TypeArguments& instantiator_type_arguments,
       intptr_t offset) const;
 
   static intptr_t length_offset() { return OFFSET_OF(RawTypeArray, length_); }
 
   static intptr_t InstanceSize() {
     ASSERT(sizeof(RawTypeArray) == OFFSET_OF(RawTypeArray, types_));
     return 0;
   }
@@ skipping 1982 matching lines @@
 }
 
 
 void Context::SetAt(intptr_t index, const Instance& value) const {
   StorePointer(InstanceAddr(index), value.raw());
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_