1385538 - EditorBase::BeginPlaceHolderTransaction() is malloc heavy

Status: RESOLVED FIXED

(Core :: DOM: Editor, defect)

Description

[(no longer active)]

The malloc as far as I can tell comes from EditorBase::mSelState, which uses UniquePtr.

UniquePtr is unfortunately an inefficient smart pointer, it encourages the programmer to dynamically allocate.  Here, dynamic allocation isn't needed at all, the object is quite small, what's needed is dynamic lifetime management.  That can be done much more efficiently with Maybe, which has inline storage.

Comment 1

[(no longer active)]

Attachment: Avoid dynamic memory allocation for EditorBase::mSelState

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)(sick)]

Comment on attachment 8891605 [details] [diff] [review]
Avoid dynamic memory allocation for EditorBase::mSelState

Really interesting.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/30a16b6553d7
Avoid dynamic memory allocation for EditorBase::mSelState; r=masayuki

Comment 4

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/30a16b6553d7