Ruby

introduce `trace_events' info for iseq.

• vm_core.h (rb_iseq_t::aux): add trace_events which represents
  which events are enabled on this iseq. With this information,
  we can skip useless trace-on changes for ISeqs.

• vm_trace.c (RUBY_EVENTS_TRACE_BY_ISEQ): moved to iseq.h and rename it
  with ISEQ_TRACE_EVENTS.

• iseq.h: introduce ISEQ_USE_COMPILE_DATA iseq (imemo) flag to represent
  COMPILE_DATA is available. In other words, iseq->aux.trace_events is not
  available when this flag is set.

  • ISEQ_COMPILE_DATA() is changed from a macro.
  • ISEQ_COMPILE_DATA_ALLOC() is added.
  • ISEQ_COMPILE_DATA_CLEAR() is added.

• iseq.c: use them.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60838 b2dd03c8-39d4-4d8f-98ff-823fe69b080e