This patch degrades performance on Crockford's jslint benchmark
(http://javascript.crockford.com/performance.html) by 10%.

I suspect we are speding too much time in opt/deopt cycles (input to
switch is not a symbol).

I am putting this patch on hold until this is investigated.

If hypothesis will be confirmed we will either need to introduce
"symbol-comparison" type feedback for comparisons or force "symbolize"
switch inputs for switches over string literals.

--
Vyacheslav Egorov


On Mon, Oct 24, 2011 at 2:27 PM,  <[email protected]> wrote:
> additional comment.
>
> I'll fix it myself and also add tests before landing.
>
>
> http://codereview.chromium.org/8373029/diff/11001/src/hydrogen.cc
> File src/hydrogen.cc (right):
>
> http://codereview.chromium.org/8373029/diff/11001/src/hydrogen.cc#newcode2719
> src/hydrogen.cc:2719: AddInstruction(new(zone())
> HCheckNonSmi(tag_value));
> Checking that tag_value is non-smi after is-symbol already segfaulted is
> not very helpful.
>
> Usually you want to check for something before you segfault.
>
> http://codereview.chromium.org/8373029/
>

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