With removal of increment operations, each node has a unique id.

runtime/vm/ast.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_AST_H_
 #define VM_AST_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
@@ skipping 87 matching lines @@
   explicit AstNode(intptr_t token_index)
       : token_index_(token_index),
         id_(GetNextId()),
         ic_data_(ICData::ZoneHandle()),
         info_(NULL) {
     ASSERT(token_index >= 0);
   }
 
   intptr_t token_index() const { return token_index_; }
 
-  virtual void SetIcDataAtId(intptr_t node_id, const ICData& value) {
-    ASSERT(id() == node_id);
-    set_ic_data(value);
+
+  const ICData& ic_data() const { return ic_data_; }
+  void set_ic_data(const ICData& value) {
+    ic_data_ = value.raw();
   }
 
-  virtual const ICData& ICDataAtId(intptr_t node_id) const {
-    ASSERT(id() == node_id);
-    return ic_data_;
-  }
-
-  virtual bool HasId(intptr_t value) const { return id_ == value; }
-
   intptr_t id() const { return id_; }
 
   void set_info(CodeGenInfo* info) { info_ = info; }
   CodeGenInfo* info() const { return info_; }
 
 #define AST_TYPE_CHECK(type, name)                                             \
   virtual bool Is##type() const { return false; }                              \
   virtual type* As##type() { return NULL; }
 NODE_LIST(AST_TYPE_CHECK)
 #undef AST_TYPE_CHECK
@@ skipping 27 matching lines @@
   // constant. Otherwise, the return value is an approximation of the
   // actual value of the const expression. The type of the returned value
   // corresponds to the type of the const expression and is either
   // Number, Integer, String, Bool, or anything else (not a subtype of
   // the former).
   virtual const Instance* EvalConstExpr() const { return NULL; }
 
  protected:
   friend class ParsedFunction;
 
-  const ICData& ic_data() const { return ic_data_; }
-  void set_ic_data(const ICData& value) {
-    ic_data_ = value.raw();
-  }
-
   static intptr_t GetNextId() {
     Isolate* isolate = Isolate::Current();
     intptr_t tmp = isolate->ast_node_id();
     isolate->set_ast_node_id(tmp + 1);
     return tmp;
   }
 
  private:
   const intptr_t token_index_;
   // Unique id per function compiled, used to match AST node to a PC.
@@ skipping 1481 matching lines @@
   const LocalVariable& context_var_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InlinedFinallyNode);
 };
 
 }  // namespace dart
 
 #undef DECLARE_COMMON_NODE_FUNCTIONS
 
 #endif  // VM_AST_H_