Bug 298148

Summary: [JSC] emit `op_typeof_is_undefined` for `typeof x>"u"`
Product: WebKit Reporter: Sosuke Suzuki <sosuke>
Component: JavaScriptCoreAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

Sosuke Suzuki
Reported 2025-08-30 06:51:17 PDT
esbuild minifies `typeof x === "undefined"` to `typeof x>"u"`. This reduces code size but is slower in JSC. This patch makes `typeof x>"u"` emit `op_typeof_is_undefined` just like `typeof x === "undefined"`.
Attachments
Sosuke Suzuki
Comment 1 2025-08-30 06:54:38 PDT
EWS
Comment 2 2025-08-30 19:27:57 PDT
Committed 299368@main (a937882ba69b): <https://commits.webkit.org/299368@main> Reviewed commits have been landed. Closing PR #50101 and removing active labels.
Radar WebKit Bug Importer
Comment 3 2025-08-30 19:28:14 PDT
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