[Webkit-unassigned] [Bug 150983] New: We should treat structures that vary solely in their prototype as a single polymorphic type.

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=150983

            Bug ID: 150983
           Summary: We should treat structures that vary solely in their
                    prototype as a single polymorphic type.
    Classification: Unclassified
           Product: WebKit
           Version: WebKit Nightly Build
          Hardware: Unspecified
                OS: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: JavaScriptCore
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: keith_miller at apple.com

Consider the following code:

function foo()
    function Bar(x) {
        this.x = x;
    }

    return new Bar(1);
}

Every time foo() is called the returned value will have a different prototype. At some point, probably the second time we construct a new Bar() we should convert the structure into a new one that instead indicates we should get the prototype off the object itself rather than off the structure. This would prevent inline caches from becoming megamorphic.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.webkit.org/pipermail/webkit-unassigned/attachments/20151107/b0fe41d8/attachment.html>