Improve type test and type equality for generics (issue 15148).

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2013, 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.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 3080 matching lines @@
 // Returns a Boolean constant if all classes in ic_data yield the same type-test
 // result and the type tests do not depend on type arguments. Otherwise return
 // Bool::null().
 RawBool* FlowGraphOptimizer::InstanceOfAsBool(const ICData& ic_data,
                                               const AbstractType& type) const {
   ASSERT(ic_data.num_args_tested() == 1);  // Unary checks only.
   if (!type.IsInstantiated() || type.IsMalformedOrMalbounded()) {
     return Bool::null();
   }
   const Class& type_class = Class::Handle(type.type_class());
-  if (type_class.NumTypeArguments() > 0) {
+  const intptr_t num_type_args = type_class.NumTypeArguments();
+  if (num_type_args > 0) {
     // Only raw types can be directly compared, thus disregarding type
     // arguments.
+    const intptr_t num_type_params = type_class.NumTypeParameters();
+    const intptr_t from_index = num_type_args - num_type_params;
     const AbstractTypeArguments& type_arguments =
         AbstractTypeArguments::Handle(type.arguments());
     const bool is_raw_type = type_arguments.IsNull() ||
-        type_arguments.IsRaw(type_arguments.Length());
+        type_arguments.IsRaw(from_index, num_type_params);
     if (!is_raw_type) {
       // Unknown result.
       return Bool::null();
     }
   }
   const ClassTable& class_table = *Isolate::Current()->class_table();
   Bool& prev = Bool::Handle();
   Class& cls = Class::Handle();
   for (int i = 0; i < ic_data.NumberOfChecks(); i++) {
     cls = class_table.At(ic_data.GetReceiverClassIdAt(i));
@@ skipping 4895 matching lines @@
   }
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits.length(); i++) {
     CreateMaterializationAt(exits[i], alloc, alloc->cls(), *fields);
   }
 }
 
 
 }  // namespace dart