1377515 - IsCJKFont shows up in gmail profile

Status: RESOLVED FIXED

(Core :: Graphics: Text, enhancement, P3)

Description

[Neerja Pancholi[:neerja]]

This gmail profile has a sample showing IsCJKFont. Spoke to jfkthame and he thinks it could be optimized. 

Profile:
https://perf-html.io/public/760909d9456fb753500182eb04f593317b948d48/calltree/?invertCallstack&search=isCJKFont&thread=5

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: Use GetFontTable rather than CopyFontTable in gfxDWriteFontEntry::IsCJKFont() to try and avoid copying

I doubt the difference is really measurable, but in principle this should be better as it tries to just access the table without copying.

Comment 2

[Bas Schouten (:bas.schouten)]

Comment on attachment 8908976 [details] [diff] [review]
Use GetFontTable rather than CopyFontTable in gfxDWriteFontEntry::IsCJKFont() to try and avoid copying

Review of attachment 8908976 [details] [diff] [review]:
-----------------------------------------------------------------

Seems like strictly an improvement to me.

::: gfx/thebes/gfxDWriteFontList.cpp
@@ +698,5 @@
>  
>      mIsCJK = false;
>  
>      const uint32_t kOS2Tag = TRUETYPE_TAG('O','S','/','2');
> +    hb_blob_t* blob = GetFontTable(kOS2Tag);

nit: Maybe add a comment that if anyone adds any early return paths here they need to remember to call hb_blob_destroy? It's a shame we don't have an RAII class for this.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/98c159aec57e
Use GetFontTable rather than CopyFontTable in gfxDWriteFontEntry::IsCJKFont() to try and avoid copying. r=bas

Comment 4

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

https://hg.mozilla.org/mozilla-central/rev/98c159aec57e