[webkit-dev] JIT probe mechanism soon required for DFG and FTL OSR Exit

Mark Lam mark.lam at apple.com
Thu Aug 10 15:29:44 PDT 2017


Looks like I have to disable DFG for the Windows port as well.  Relevant bugs:
https://bugs.webkit.org/show_bug.cgi?id=175447 <https://bugs.webkit.org/show_bug.cgi?id=175447>
https://bugs.webkit.org/show_bug.cgi?id=175449 <https://bugs.webkit.org/show_bug.cgi?id=175449>

Mark

> On Aug 10, 2017, at 3:04 PM, Mark Lam <mark.lam at apple.com> wrote:
> 
> FYI, following up on this work, I’ll soon land patches that relies on the probe mechanism being available.  So, I will now make the JIT probe (MASM_PROBE) a mandatory feature in order to enable the DFG and FTL (see https://bugs.webkit.org/show_bug.cgi?id=175446 <https://bugs.webkit.org/show_bug.cgi?id=175446>).  As a consequence, I’ll be disabling the DFG for the MIPS port in this patch.
> 
> Mark
> 
>> On Jul 19, 2017, at 9:52 AM, Mark Lam <mark.lam at apple.com <mailto:mark.lam at apple.com>> wrote:
>> 
>> 
>> 
>>> On Jul 19, 2017, at 9:49 AM, Konstantin Tokarev <annulen at yandex.ru <mailto:annulen at yandex.ru>> wrote:
>>> 
>>> 
>>> 
>>> 19.07.2017, 02:49, "Mark Lam" <mark.lam at apple.com <mailto:mark.lam at apple.com>>:
>>>> FYI, I’m looking into making OSR exits work in a more memory efficient way using the JIT probe mechanism.  Once we make this transition, the DFG and FTL will not work for any CPU targets that don’t support the JIT probe mechanism.  The API to the JIT probe will probably change as well as this work progresses.  I’ll take care of updating all the probe implementations for ARM and x86 variants.
>>>> 
>>>> AFAICT, only CPU(MIPS) does not currently support the probe mechanism.  It’s up to the MIPS folks to implement that support if they want to continue to use the DFG.  Feel free to contact me if you have questions regarding the probe mechanism.
>>>> 
>>>> This work will be tracked in https://bugs.webkit.org/show_bug.cgi?id=174645 <https://bugs.webkit.org/show_bug.cgi?id=174645>.
>>> 
>>> Could you elaborate, what code needs to be implemented for MIPS?
>> 
>> See everything guarded by ENABLE(MASM_PROBE) in MacroAssemblerX86Common.cpp.  You’ll need to have the equivalent for MIPS.  Eventually, we may need some additional changes as well, but that depends on the solution currently being investigated.
>> 
>> Mark
>> 
>>> 
>>>> 
>>>> Thanks.
>>>> 
>>>> Mark
>>>> 
>>>> ,
>>>> 
>>>> _______________________________________________
>>>> webkit-dev mailing list
>>>> webkit-dev at lists.webkit.org <mailto:webkit-dev at lists.webkit.org>
>>>> https://lists.webkit.org/mailman/listinfo/webkit-dev
>>> 
>>> 
>>> -- 
>>> Regards,
>>> Konstantin
>> 
>> _______________________________________________
>> webkit-dev mailing list
>> webkit-dev at lists.webkit.org <mailto:webkit-dev at lists.webkit.org>
>> https://lists.webkit.org/mailman/listinfo/webkit-dev <https://lists.webkit.org/mailman/listinfo/webkit-dev>
> _______________________________________________
> webkit-dev mailing list
> webkit-dev at lists.webkit.org
> https://lists.webkit.org/mailman/listinfo/webkit-dev

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-dev/attachments/20170810/7f155e50/attachment.html>


More information about the webkit-dev mailing list