diff -r d96f52012aaa -r 740e263c80c6 src/cpu/x86/vm/macroAssembler_x86.hpp
--- a/src/cpu/x86/vm/macroAssembler_x86.hpp	Wed Aug 14 15:12:00 2013 -0700
+++ b/src/cpu/x86/vm/macroAssembler_x86.hpp	Thu Aug 15 20:04:10 2013 -0400
@@ -371,6 +371,10 @@
   void cmp_narrow_klass(Register dst, Klass* k);
   void cmp_narrow_klass(Address dst, Klass* k);
 
+  // Returns the byte size of the instructions generated by decode_klass_not_null()
+  // when compressed klass pointers are being used.
+  static int instr_size_for_decode_klass_not_null();
+
   // if heap base register is used - reinit it with the correct value
   void reinit_heapbase();