[webkit-reviews] review denied: [Bug 18436] Need to throw exception on read/modify/write or similar resolve for nonexistent property : [Attachment 20544] Slightly updated

[bugzilla-daemon at webkit.org]

Geoffrey Garen <ggaren at apple.com> has denied Oliver Hunt <oliver at apple.com>'s
request for review:
Bug 18436: Need to throw exception on read/modify/write or similar resolve for
nonexistent property
http://bugs.webkit.org/show_bug.cgi?id=18436

Attachment 20544: Slightly updated
http://bugs.webkit.org/attachment.cgi?id=20544&action=edit

------- Additional Comments from Geoffrey Garen <ggaren at apple.com>
This patch is really 3 patches:
(1) Fix a bug where resolve-dependent writes do a get_prop_id and/or
put_prop_id instead of a full resolve.
(2) Add a superinstruction optimization that merges resolve_base and resolve.
(3) Add exception checks after resolve operations.

Because each of these is a substantial change, I think each should land
separately.

Taken individually:

Fix (1) needs to include assign and for-in, not just read/modify.

Fix (2) seems like a nice optimization, but why not do this as a peephole
optimization in the code generator? 

Fix (3) needs to include normal resolve and resolve_base, not just read/modify.
I'd also like to know exactly what the cost of fix (3) is before we land it, to
make sure it doesn't cost more than we would reasonably expect.