[webkit-reviews] review denied: [Bug 21099] Temporary JSNumberCells are not reused. : [Attachment 23818] Some sort of runtime check for SSE, since Windows and Linux run on CPUs that may not support it.

[bugzilla-daemon at webkit.org]

Maciej Stachowiak <mjs at apple.com> has denied Gavin Barraclough
<barraclough at apple.com>'s request for review:
Bug 21099: Temporary JSNumberCells are not reused.
https://bugs.webkit.org/show_bug.cgi?id=21099

Attachment 23818: Some sort of runtime check for SSE, since Windows and Linux
run on CPUs that may not support it.
https://bugs.webkit.org/attachment.cgi?id=23818&action=edit

------- Additional Comments from Maciej Stachowiak <mjs at apple.com>
I mentioned some style comments on IRC.

There does appear to be one substantive bug, which is that sometimes a cell
will be reused when the result should have been packed in an immediate. For
instance, 2 * 0.5 will be left in a cell. Various parts of our engine assume
that immediate-sized values can't be in a cell, including switch and ===.

So for example with this patch, 1 === 0.5 + 0.5 would return false.