Fix type test elimination using static type propagation in new compiler.

runtime/vm/object.h

 // Copyright (c) 2012, 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 "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 319 matching lines @@
   static RawError* Init(Isolate* isolate);
   static void InitFromSnapshot(Isolate* isolate);
   static void InitOnce();
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawObject));
   }
 
   static const ObjectKind kInstanceKind = kObject;
 
+  // Different kinds of type tests.
+  enum TypeTestKind {
+    kIsSubtypeOf = 0,
+    kIsMoreSpecificThan
+  };
+
  protected:
   // Used for extracting the C++ vtable during bringup.
   Object() : raw_(null_) {}
 
   uword raw_value() const {
     return reinterpret_cast<uword>(raw());
   }
 
   inline void SetRaw(RawObject* value);
 
@@ skipping 245 matching lines @@
   }
 
   // Check if this class represents a canonical signature class, i.e. not an
   // alias as defined in a typedef.
   bool IsCanonicalSignatureClass() const;
 
   // Check the subtype relationship.
   bool IsSubtypeOf(const AbstractTypeArguments& type_arguments,
                    const Class& other,
                    const AbstractTypeArguments& other_type_arguments,
-                   Error* malformed_error) const;
+                   Error* malformed_error) const {
+    return TypeTest(kIsSubtypeOf,
+                    type_arguments,
+                    other,
+                    other_type_arguments,
+                    malformed_error);
+  }
+
+  // Check the 'more specific' relationship.
+  bool IsMoreSpecificThan(const AbstractTypeArguments& type_arguments,
+                          const Class& other,
+                          const AbstractTypeArguments& other_type_arguments,
+                          Error* malformed_error) const {
+    return TypeTest(kIsMoreSpecificThan,
+                    type_arguments,
+                    other,
+                    other_type_arguments,
+                    malformed_error);
+  }
 
   // Check if this is the top level class.
   bool IsTopLevel() const;
 
   RawArray* fields() const { return raw_ptr()->fields_; }
   void SetFields(const Array& value) const;
 
   // Returns true if non-static fields are defined.
   bool HasInstanceFields() const;
 
@@ skipping 116 matching lines @@
   RawFunction* LookupAccessorFunction(const char* prefix,
                                       intptr_t prefix_length,
                                       const String& name) const;
 
   // Allocate an instance class which has a VM implementation.
   template <class FakeInstance> static RawClass* New(intptr_t id);
   template <class FakeInstance> static RawClass* New(const String& name,
                                                      const Script& script,
                                                      intptr_t token_index);
 
+  // Check the subtype or 'more specific' relationship.
+  bool TypeTest(TypeTestKind test_kind,
+                const AbstractTypeArguments& type_arguments,
+                const Class& other,
+                const AbstractTypeArguments& other_type_arguments,
+                Error* malformed_error) const;
+
   HEAP_OBJECT_IMPLEMENTATION(Class, Object);
   friend class Object;
   friend class Instance;
+  friend class AbstractType;
   friend class Type;
 };
 
 
 // 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:
   RawLibraryPrefix* library_prefix() const {
     return raw_ptr()->library_prefix_;
@@ skipping 108 matching lines @@
   // Check if this type is an interface type.
   bool IsInterfaceType() const {
     if (!HasResolvedTypeClass()) {
       return false;
     }
     const Class& cls = Class::Handle(type_class());
     return !cls.IsNull() && cls.is_interface();
   }
 
   // Check the subtype relationship.
-  bool IsSubtypeOf(const AbstractType& other, Error* malformed_error) const;
+  bool IsSubtypeOf(const AbstractType& other, Error* malformed_error) const {
+    return TypeTest(kIsSubtypeOf, other, malformed_error);
+  }
+
+  // Check the 'more specific' relationship.
+  bool IsMoreSpecificThan(const AbstractType& other,
+                          Error* malformed_error) const {
+    return TypeTest(kIsMoreSpecificThan, other, malformed_error);
+  }
+
+ private:
+  // Check the subtype or 'more specific' relationship.
+  bool TypeTest(TypeTestKind test_kind,
+                const AbstractType& other,
+                Error* malformed_error) const;
 
  protected:
   HEAP_OBJECT_IMPLEMENTATION(AbstractType, Object);
   friend class Class;
+  friend class AbstractTypeArguments;
 };
 
 
 // A Type consists of a class, possibly parameterized with type
 // arguments. Example: C<T1, T2>.
 // An unresolved class is a String specifying the class name.
 //
 // Caution: 'RawType*' denotes a 'raw' pointer to a VM object of class Type, as
 // opposed to 'Type' denoting a 'handle' to the same object. 'RawType' does not
 // relate to a 'raw type', as opposed to a 'cooked type' or 'rare type'.
@@ skipping 188 matching lines @@
 
   // Check that this type argument vector is within the declared bounds of the
   // given class or interface. If not, set malformed_error (if not yet set).
   bool IsWithinBoundsOf(const Class& cls,
                         const AbstractTypeArguments& bounds_instantiator,
                         Error* malformed_error) const;
 
   // Check the subtype relationship, considering only a prefix of length 'len'.
   bool IsSubtypeOf(const AbstractTypeArguments& other,
                    intptr_t len,
-                   Error* malformed_error) const;
+                   Error* malformed_error) const {
+    return TypeTest(kIsSubtypeOf, other, len, malformed_error);
+  }
+
+  // Check the 'more specific' relationship, considering only a prefix of
+  // length 'len'.
+  bool IsMoreSpecificThan(const AbstractTypeArguments& other,
+                          intptr_t len,
+                          Error* malformed_error) const {
+    return TypeTest(kIsMoreSpecificThan, other, len, malformed_error);
+  }
 
   bool Equals(const AbstractTypeArguments& other) const;
 
   // UNREACHABLEs as AbstractTypeArguments is an abstract class.
   virtual intptr_t Length() const;
   virtual RawAbstractType* TypeAt(intptr_t index) const;
   virtual void SetTypeAt(intptr_t index, const AbstractType& value) const;
   virtual bool IsResolved() const;
   virtual bool IsInstantiated() const;
   virtual bool IsUninstantiatedIdentity() const;
 
  private:
   // Check if this type argument vector consists solely of DynamicType,
   // considering only a prefix of length 'len'.
   // If raw_instantiated is true, consider each type parameter to be first
   // instantiated from a vector of dynamic types.
   bool IsDynamicTypes(bool raw_instantiated, intptr_t len) const;
 
+  // Check the subtype or 'more specific' relationship, considering only a
+  // prefix of length 'len'.
+  bool TypeTest(TypeTestKind test_kind,
+                const AbstractTypeArguments& other,
+                intptr_t len,
+                Error* malformed_error) const;
+
  protected:
   HEAP_OBJECT_IMPLEMENTATION(AbstractTypeArguments, Object);
   friend class Class;
 };
 
 
 // A TypeArguments is an array of AbstractType.
 class TypeArguments : public AbstractTypeArguments {
  public:
   virtual intptr_t Length() const;
@@ skipping 3857 matching lines @@
 }
 
 
 intptr_t Stackmap::SizeInBits() const {
   return (Smi::Value(raw_ptr()->bitmap_size_in_bytes_) * kBitsPerByte);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_