The typed function references proposal adds a `ref.as_non_null` instruction: https://github.com/WebAssembly/function-references/blob/main/proposals/function-references/Overview.md#optional-references It is currently unimplemented in JSC.
Pull request: https://github.com/WebKit/WebKit/pull/8997
Committed 259420@main (cdfc2fb66572): <https://commits.webkit.org/259420@main> Reviewed commits have been landed. Closing PR #8997 and removing active labels.
<rdar://problem/104691080>