Bug 216222 – [JSC] Special property caching should check Structure's cacheability

• Component: New Bugs
• Status: RESOLVED FIXED

[Yusuke Suzuki]

[JSC] ModuleNamespaceObject's property caching has different mechanism than IC

[Yusuke Suzuki]

Created attachment 408116 [details]
Patch

[Radar WebKit Bug Importer]

<rdar://problem/68415681>

[Yusuke Suzuki]

Comment on attachment 408116 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=408116&action=review

> JSTests/stress/not-cache-over-uncacheable-dictionary.js:14
> +function shouldBe(actual, expected) {
> +    if (actual !== expected)
> +        throw new Error('bad value: ' + actual);
> +}
> +
> +var object = {};
> +$vm.toUncacheableDictionary(object);
> +shouldBe(String(object), `[object Object]`);
> +shouldBe(String(object), `[object Object]`);
> +shouldBe(String(object), `[object Object]`);
> +object[Symbol.toStringTag] = "OK";
> +shouldBe(String(object), `[object OK]`);
> +shouldBe(String(object), `[object OK]`);
> +shouldBe(String(object), `[object OK]`);

This test does not fail without this patch while we were caching. This is because we are relying on watchpoints for properties instead of structure ID.
But in this patch, we changed the code not to cache properties in uncacheable-dictionary. So testing it here is nice.

[Yusuke Suzuki]

Created attachment 408117 [details]
Patch

[Yusuke Suzuki]

Created attachment 408118 [details]
Patch

[Ryan Haddad]

*** Bug 216262 has been marked as a duplicate of this bug. ***

[Saam Barati]

Comment on attachment 408118 [details]
Patch

r=me

[Yusuke Suzuki]

Committed r266715: <https://trac.webkit.org/changeset/266715>