bug#60953: The :match predicate with large regexp in tree-sitter font-lock seems inefficient

[Dmitry Gutov]

On 31/01/2023 20:16, Dmitry Gutov wrote:
> Anyway, it seems like it might be too late as an addition to Emacs 29. 
> And we can implement the match predicate using narrowing for this 
> release, to be updated later.

So here. I've installed the first patch, which didn't raise up too many 
concerns previously, and here's the new iteration on the second patch. 
Please see the attachment.

To note the numbers: the first patch does quite well to improve the 
performance of modes which use :match in queries which match a lot of 
nodes (e.g. rust-ts-mode or ruby-ts-mode). There boost in those was on 
the order of 25%.

The second one is longer, and the boost (on top of the first one) is 
around 5-6%, stable. Not as impressive, but at least it brings :match's 
performance a little above :pred's in my example.

treesit_predicate_match.diff
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