Use bit fields to calculate compare stub minor key

src/codegen.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 343 matching lines @@
  private:
   Condition cc_;
   bool strict_;
   // Only used for 'equal' comparisons.  Tells the stub that we already know
   // that at least one side of the comparison is not NaN.  This allows the
   // stub to use object identity in the positive case.  We ignore it when
   // generating the minor key for other comparisons to avoid creating more
   // stubs.
   bool never_nan_nan_;
 
+  // Encoding of the minor key CCCCCCCCCCCCCCNS.
+  class StrictField: public BitField<bool, 0, 1> {};
+  class NeverNanNanField: public BitField<bool, 1, 1> {};
+  class ConditionField: public BitField<int, 2, 14> {};
+
   Major MajorKey() { return Compare; }
 
   int MinorKey();
 
   // Branch to the label if the given object isn't a symbol.
   void BranchIfNonSymbol(MacroAssembler* masm,
                          Label* label,
                          Register object,
                          Register scratch);
 
@@ skipping 208 matching lines @@
  private:
   Major MajorKey() { return ToBoolean; }
   int MinorKey() { return 0; }
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODEGEN_H_