1371061 - nsBaseHashtable::GetOrInsert does two hashtable lookups in the Insert case

Status: RESOLVED FIXED

(Core :: XPCOM, defect)

Description

[Mats Palmgren (inactive)]

http://searchfox.org/mozilla-central/rev/1a054419976437d0778a2b89be1b00207a744e94/xpcom/ds/nsBaseHashtable.h#126,131
This is bad for performance obviously.

Comment 1

[Mats Palmgren (inactive)]

It seems to me we could just do a PutEntry instead:
http://searchfox.org/mozilla-central/rev/1a054419976437d0778a2b89be1b00207a744e94/xpcom/ds/nsTHashtable.h#147

Comment 2

[Mats Palmgren (inactive)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=8390815b624edc0837e60f53006ce4a1d53ca50b

Comment 3

[Nathan Froyd [:froydnj]]

Thanks for fixing this.  I didn't push very hard in the initial bug to do the Right Thing, but I see now that it wouldn't have been very hard to do the Right Thing, which is completely my fault!

Comment 4

[Mats Palmgren (inactive)]

Attachment: Optimize nsBaseHashtable::GetOrInsert() to only do a single hashtable lookup

Try looks green so far so I think it'll pass.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/97735d7197e2
Optimize nsBaseHashtable::GetOrInsert() to only do a single hashtable lookup.  r=froydnj

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/97735d7197e2