Speed up the Dart_IsBlah functions by checking the class index. This

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 218 matching lines @@
 
   bool IsNewObject() const {
     uword addr = reinterpret_cast<uword>(this);
     return (addr & kNewObjectAlignmentOffset) == kNewObjectAlignmentOffset;
   }
   bool IsOldObject() const {
     uword addr = reinterpret_cast<uword>(this);
     return (addr & kNewObjectAlignmentOffset) == kOldObjectAlignmentOffset;
   }
 
+  intptr_t GetClassTag() const {

[Ivan Posva, 2012/05/09 23:28:16]

Should we make this private?

[turnidge, 2012/05/10 17:49:38]

Done.

+    uword tags = ptr()->tags_;
+    return ClassTag::decode(tags);
+  }
+
   // Support for GC marking bit.
   bool IsMarked() const {
     return MarkBit::decode(ptr()->tags_);
   }
   void SetMarkBit() {
     ASSERT(!IsMarked());
     uword tags = ptr()->tags_;
     ptr()->tags_ = MarkBit::update(true, tags);
   }
   void ClearMarkBit() {
@@ skipping 1108 matching lines @@
   intptr_t type_;  // Uninitialized, simple or complex.
   intptr_t flags_;  // Represents global/local, case insensitive, multiline.
 
   // Variable length data follows here.
   uint8_t data_[0];
 };
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_