Bug 258758

Summary:	Restore Path cheap copying (refcount/COW PathStream)
Product:	WebKit	Reporter:	Simon Fraser (smfr) <simon.fraser>
Component:	Layout and Rendering	Assignee:	Simon Fraser (smfr) <simon.fraser>
Status:	RESOLVED FIXED
Severity:	Normal	CC:	bfulgham, sabouhallawa, simon.fraser, webkit-bug-importer, zalan
Priority:	P2	Keywords:	InRadar
Version:	WebKit Local Build
Hardware:	Unspecified
OS:	Unspecified

Description Simon Fraser (smfr) 2023-06-30 17:17:32 PDT

After 265569@main, copying a Path with a PathStream impl results in cloning the PathStream, which might be large. This breaks the assumption of most of the existing code, that copying a Path is cheap because it's just refCounting a CGPathRef.

So we should restore cheap copy, and make the PathStream copy-on-write.

Comment 1 Radar WebKit Bug Importer 2023-06-30 17:18:03 PDT

<rdar://problem/111595182>

Comment 2 Simon Fraser (smfr) 2023-07-05 17:44:15 PDT

Pull request: https://github.com/WebKit/WebKit/pull/15584

Comment 3 EWS 2023-07-06 10:01:58 PDT

Committed 265810@main (bb3cac815bdf): <https://commits.webkit.org/265810@main>

Reviewed commits have been landed. Closing PR #15584 and removing active labels.