[webkit-reviews] review requested: [Bug 14868] Import variable lookup optimizations from KJS : [Attachment 15815] Proposed patch

[bugzilla-daemon at webkit.org]

Cameron Zwarich (cpst) <cwzwarich at uwaterloo.ca> has asked  for review:
Bug 14868: Import variable lookup optimizations from KJS
http://bugs.webkit.org/show_bug.cgi?id=14868

Attachment 15815: Proposed patch
http://bugs.webkit.org/attachment.cgi?id=15815&action=edit

------- Additional Comments from Cameron Zwarich (cpst)
<cwzwarich at uwaterloo.ca>
Here is a first attempt at a patch to import these changes into WebKit, most
likely into the feature branch. I wasn't really sure how to deal with all of
the different coding styles, so I am sure there are some problems in that area.
I ported over all of our later changes where we diverge with KJS, so this
passes all of our JSC and layout tests, with a few exceptions:

* Two of the JSC tests require function declarations to be processed in the
scope of a with block, whereas this seems incorrect from my reading of the ECMA
spec. Internet Explorer also agrees with my understanding of the spec and the
new code, so it is unlikely that there would be any compatibility issues with
this change.

* In the fast/js/kde/function test, there was a strange test case about nested
function declarations. The new code fails this test, but the behaviour expected
in the test case seems completely wrong to me. I don't really even know why
it's there.

I've added the new and updated tests from KDE, which give pretty good coverage
of any changes in functionality, but I would still like to make a set of tests
with better code coverage of nodes.cpp than the current tests.