Bug 183435

Summary:

[JSC] Optimize inherits<T> if T is final type

Product:

WebKit

Reporter:

Yusuke Suzuki <ysuzuki>

Component:

JavaScriptCore

Assignee:

Yusuke Suzuki <ysuzuki>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

ews-watchlist, joepeck, keith_miller, mark.lam, msaboff, saam, webkit-bug-importer

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

Bug Depends on:

183429

Bug Blocks:

Attachments:

Description	Flags
Patch	none
Patch	mark.lam: review+

Yusuke Suzuki

Reported 2018-03-08 01:32:56 PST

If T is a final type, we do not need to traverse hierarchy. Consider a final type T, jsDynamicCast<T*>(vm, cell); in this case, if (cell->classInfo(vm) == T::info()) return static_cast<T*>(cell); return nullptr; is enough. We can this optimization in JSCast.h with std::is_final<T>.

Attachments
Patch (131.62 KB, patch) 2018-03-08 08:19 PST, Yusuke Suzuki	no flags	Details Formatted Diff Diff
Patch (130.93 KB, patch) 2018-03-08 09:22 PST, Yusuke Suzuki	mark.lam: review+	Details Formatted Diff Diff
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