Feature #20589
closedResize array in `rb_ary_freeze` and use `rb_ary_freeze` internally for arrays
Description
GitHub PR https://github.com/ruby/ruby/pull/11030
This is a redo of https://github.com/ruby/ruby/pull/2640 and a new issue for the array portion of https://bugs.ruby-lang.org/issues/16291 because both are stale.
This change proposes the following:
- Call
ary_shrink_capa
fromrb_ary_freeze
to resize arrays before freezing (if they are not embedded, not shared, and not a shared root). - Update callers to use
rb_ary_freeze
instead ofrb_obj_freeze
internally in CRuby/ - Add an assertion to
ary_heap_realloc
that ensures frozen arrays are not being reallocated.\
The orignal issue implemented this for performance reasons, which are still valid. However, additionally this ensures that frozen arrays are not being passed to ary_heap_realloc
and also ensures the capacity is set with ARY_SET_CAPA
in ary_shrink_capa
. Previously, because ARY_SET_CAPA
was not called, ary_heap_realloc
would get called after the array was frozen (when that is unnecessary).
Array memsize before and after this change:
Before:
$ require 'objspace'
=> false
$ a = (1..5).to_a
=> [1, 2, 3, 4, 5]
$ ObjectSpace.memsize_of(a)
=> 200
$ a.freeze
=> [1, 2, 3, 4, 5]
$ ObjectSpace.memsize_of(a)
=> 200
After:
$ require 'objspace'
=> false
$ a = (1..5).to_a
=> [1, 2, 3, 4, 5]
$ ObjectSpace.memsize_of(a)
=> 200
$ a.freeze
=> [1, 2, 3, 4, 5]
$ ObjectSpace.memsize_of(a)
=> 80
Updated by byroot (Jean Boussier) 5 months ago
- Related to Feature #16291: Introduce support for resize in rb_ary_freeze and prefer internal use of rb_ary_freeze and rb_str_freeze for String and Array types added
Updated by byroot (Jean Boussier) 4 months ago
- Status changed from Open to Closed
Closing given https://github.com/ruby/ruby/pull/11030 was merged yesterday.
However it caused some assertions failures in corner cases, so I opened a followup: https://github.com/ruby/ruby/pull/11092