In optimized code use IC calls for instance calls that have no IC data instead of deoptimizing. The…

runtime/vm/raw_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_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/globals.h"
 #include "vm/token.h"
@@ skipping 915 matching lines @@
   }
   RawFunction* function_;     // Parent/calling function of this IC.
   RawString* target_name_;    // Name of target function.
   RawArray* ic_data_;         // Contains test class-ids and target functions.
   RawObject** to() {
     return reinterpret_cast<RawObject**>(&ptr()->ic_data_);
   }
   intptr_t deopt_id_;         // Deoptimization id corresponding to this IC.
   intptr_t num_args_tested_;  // Number of arguments tested in IC.
   uint8_t deopt_reason_;      // Last deoptimization reason.
+  uint8_t is_closure_call_;   // 0 or 1.
 };
 
 
 class RawSubtypeTestCache : public RawObject {
   RAW_HEAP_OBJECT_IMPLEMENTATION(SubtypeTestCache);
   RawArray* cache_;
 };
 
 
 class RawError : public RawObject {
@@ skipping 687 matching lines @@
          kExternalUint64ArrayCid == kExternalInt8ArrayCid + 7 &&
          kExternalFloat32ArrayCid == kExternalInt8ArrayCid + 8 &&
          kExternalFloat64ArrayCid == kExternalInt8ArrayCid + 9 &&
          kStacktraceCid == kExternalInt8ArrayCid + 10);
   return (index >= kExternalInt8ArrayCid && index <= kExternalFloat64ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_