Uses a conditional move for usage counter increment instead of a branch

runtime/vm/assembler_ia32.h

 // 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.
 
 #ifndef VM_ASSEMBLER_IA32_H_
 #define VM_ASSEMBLER_IA32_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_ia32.h directly; use assembler.h instead.
 #endif
@@ skipping 330 matching lines @@
 
   void movzxw(Register dst, Register src);
   void movzxw(Register dst, const Address& src);
   void movsxw(Register dst, Register src);
   void movsxw(Register dst, const Address& src);
   void movw(Register dst, const Address& src);
   void movw(const Address& dst, Register src);
 
   void leal(Register dst, const Address& src);
 
+  void cmovno(Register dst, Register src);
   void cmove(Register dst, Register src);
   void cmovs(Register dst, Register src);
   void cmovns(Register dst, Register src);
 
   void cmovgel(Register dst, Register src);
   void cmovlessl(Register dst, Register src);
 
   void rep_movsb();
 
   void movss(XmmRegister dst, const Address& src);
@@ skipping 537 matching lines @@
 }
 
 
 inline void Assembler::EmitOperandSizeOverride() {
   EmitUint8(0x66);
 }
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_IA32_H_