1175621 - use moves inside WrapRunnable* functions

Status: RESOLVED FIXED

Description

[Nathan Froyd [:froydnj]]

Using moves inside WrapRunnable* when creating the actual runnable has two benefits:

1. We avoid some unnecessary copying of things.  (Any necessary copies are already done by the call to WrapRunnable*, assuming I understand C++ semantics.)
2. We correctly handle objects that have move constructors, but don't have copy constructors.

#2 is especially important to me in the context of bug 1162026, since TemporaryRef<T> has a copy constructor, but converting TemporaryRef<T> usages to already_AddRefed<T> causes issues, since already_AddRefed<T> doesn't have a copy constructor.

Comment 1

[Nathan Froyd [:froydnj]]

Attachment: make WrapRunnable* more efficient by utilizing moves in wrapper functions

Calls to WrapRunnable* copy their arguments already; we don't need to
copy them a second time when constructing the actual runnable.  In
addition to making things more efficient, this change also permits calls
to WrapRunnable to correctly handle objects that can only be moved, and
not copied.

Comment 2

[Nathan Froyd [:froydnj]]

Comment on attachment 8623806 [details] [diff] [review]
make WrapRunnable* more efficient by utilizing moves in wrapper functions

Review of attachment 8623806 [details] [diff] [review]:
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jesup suggested Byron might be a lower-latency reviewer.

Comment 3

[Eric Rescorla (:ekr)]

Comment on attachment 8623806 [details] [diff] [review]
make WrapRunnable* more efficient by utilizing moves in wrapper functions

Review of attachment 8623806 [details] [diff] [review]:
-----------------------------------------------------------------

LGTM

Comment 4

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/468e862d122a

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/468e862d122a