RUBY_ENCODING_MASK   37 include/ruby/encoding.h #define ENCODING_MASK RUBY_ENCODING_MASK
RUBY_ENCODING_MASK   40 include/ruby/encoding.h     RBASIC(obj)->flags &= ~RUBY_ENCODING_MASK;\
RUBY_ENCODING_MASK   46 include/ruby/encoding.h     (int)((RBASIC(obj)->flags & RUBY_ENCODING_MASK)>>RUBY_ENCODING_SHIFT)