1771060 - [CTW] Caching lines is slow with large blocks

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect)

Description

[James Teh [:Jamie]]

Spun off bug 1770606.

When sending the cache for a subtree containing a large block, IsLocalAccAtLineStart is slow because it does a linear walk of the lines in the block. With the cursor changes in bug 1770981, we can optimise this by using the line cursor. This way, subsequent calls to fetch subsequent lines in the same block will be much faster.

This will require switching to nsBlockInFlowLineIterator, since nsLineIterator doesn't support the cursor. We don't actually care about line numbers anyway, so nsLineIterator isn't necessary.

Comment 1

[James Teh [:Jamie]]

Attachment: Bug 1771060: Make use of the line cursor in IsLocalAccAtLineStart to improve performance.

nsLineIterator doesn't use the line cursor, so switch to nsBlockInFlowLineIterator.
We don't actually care about the line number here anyway.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/fc89774bca04
Make use of the line cursor in IsLocalAccAtLineStart to improve performance. r=jfkthame

Comment 3

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/fc89774bca04