Bug 252176

Summary: [css-nesting] Save memory when we only need old-school StyleRule (=non nested)
Product: WebKit Reporter: Matthieu Dubet <m_dubet>
Component: WebCore Misc.Assignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

Description Matthieu Dubet 2023-02-13 09:28:52 PST
Support for CSS Nesting adds 2 members to the StyleRule class (the resolved selector list, and the list of children rules).

This creates a regression in Membuster benchmark (~2Mb). 

We should have a "happy path" where we don't pay the memory cost of the nesting feature when we don't need it.
Comment 1 Radar WebKit Bug Importer 2023-02-13 09:29:10 PST
<rdar://problem/105399781>
Comment 2 Matthieu Dubet 2023-02-13 10:04:24 PST
Pull request: https://github.com/WebKit/WebKit/pull/10044
Comment 3 EWS 2023-02-14 15:21:13 PST
Committed 260281@main (9db1de406e2b): <https://commits.webkit.org/260281@main>

Reviewed commits have been landed. Closing PR #10044 and removing active labels.