Commit Graph

1 Commits

Author SHA1 Message Date
Z Nguyen-Huu
1f4bec2775 Add new nonextensible element kinds
Currently the backing store and elements kind might not aligned aka
backing store can be dictionary where elements kind is frozen/sealed
element kinds or the other way around. The reason is that
Object.preventExtensions change elements kind to DICTIONARY while
Object.seal/freeze change elements kind to SEALED/FROZEN element kind.
Apply both these operations can lead to that problem as in
chromium:992914

To solve this issue, we avoid Object.preventExtensions to change backing
store to dictionary by introducing new nonextensible elements kind.
These new nonextensible elements kind are handled similar to frozen,
sealed element kinds. This change not only fixes the problem but also
optimize the performance of nonextensible objects.

Change-Id: Iffc7f14eb48223c11abf3c577f305d2d072eb65b
Bug: chromium:992914, v8:6831
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1760976
Commit-Queue: Z Nguyen-Huu <duongn@microsoft.com>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63432}
2019-08-28 17:24:49 +00:00