gc.c (gc_mark): get rid of pushing useless objests.
* gc.c (rgengc_rememberset_mark): bypass gc_mark() in order to push
sunny old object at minor gc.
* gc.c (gc_mark_children): move sunny old check to gc_mark().
* gc.c (rgengc_check_shady): remove DEMOTE that already unnecessary.
* gc.c (rb_gc_writebarrier): ditto.
change sunny old check point in order to save mark stack and
remove unnatural rest_sweep & demote.
gc.c (gc_mark): get rid of pushing useless objests.
* gc.c (rgengc_rememberset_mark): bypass gc_mark() in order to push
sunny old object at minor gc.
* gc.c (gc_mark_children): move sunny old check to gc_mark().
* gc.c (rgengc_check_shady): remove DEMOTE that already unnecessary.
* gc.c (rb_gc_writebarrier): ditto.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41097 b2dd03c8-39d4-4d8f-98ff-823fe69b080e