From: normalperson@...
Date: 2015-08-14T19:29:50+00:00
Subject: [ruby-core:70392] [Ruby trunk - Misc #11447] [Open] [PATCH] iseq: move iseq->body->mark_ary to iseq->mark_ary

Issue #11447 has been reported by Eric Wong.

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Misc #11447: [PATCH] iseq: move iseq->body->mark_ary to iseq->mark_ary
https://bugs.ruby-lang.org/issues/11447

* Author: Eric Wong
* Status: Open
* Priority: Normal
* Assignee: 
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Having an unused dummy field is ugly and wasteful.  mark_ary was
chosen here since it is often touched at a different point in
execution (GC) than during normal execution of the iseq code.

The GC performance impact is is probably immeasurable given
RGenGC, and rb_location_t still resides in the body for marking
(however on a different cache line than mark_ary was).

Overall, this should not make a real difference today since most
mallocs give 2 word alignment for compliance and compatibility,
but it should allow us more room to make future modifications to
rb_iseq_constant_body without using more space.


Feel free to reject if there's something better planned for the
dummy field (and perhaps name it "feature_TODO" instead of "dummy2")
so somebody else doesn't write a patch like this one :)
Otherwise I'll commit in a week or so.


---Files--------------------------------
0001-iseq-move-iseq-body-mark_ary-to-iseq-mark_ary.patch (3.1 KB)


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