[webkit-dev] x32 support of JavaScriptCore

[Kenneth Rohde Christiansen]

OK, I see.

If most of your changes are in JavaScriptCore, it might be possible to
just have a build bot that builds that and runs the unit tests for
now, then later get all of WebKit tested.

Kenneth

On Thu, Oct 11, 2012 at 9:13 AM, Xian, Yuqiang <yuqiang.xian at intel.com> wrote:
> Thanks for the suggestions, Kenneth.
>
> I'm refining the code and trying to enable the last major component - the low level interpreter for x32.
> Yes it's ideal if we can upstream the code, and as you mentioned, keep maintaining it. The buildbot is a good idea while we are still way far from it - it requires a mature x32 system which at least supports all of the things that a WebKit port depends on. I know there're efforts porting Gentoo and Fedora to x32 - we may depend on each other.
>
> Currently I'm testing the JSC shell only. Though I use the EFL port, I eliminated most of the unnecessary dependencies on EFL libraries to run the JSC shell, so that I don't need to put efforts on compiling and enabling those dependencies for x32 at current stage.
>
> Thanks, -Yuqiang
>
> -----Original Message-----
> From: Kenneth Rohde Christiansen [mailto:kenneth.christiansen at gmail.com]
> Sent: 2012年10月11日 5:51
> To: Xian, Yuqiang
> Cc: webkit-dev at lists.webkit.org
> Subject: Re: [webkit-dev] x32 support of JavaScriptCore
>
> Hi,
>
> I don't think another branch on webkit.org will help you much; then
> you can as well have a branch anywhere.
>
> If you want this code to be well tested and maintained, you need to
> get it upstream (through all the review process) and promise that you
> have resources to keep maintaining it. It will also be an advantage if
> we can get a buildbot running this exact configuration, so that others
> can make sure they don't break your code.
>
> I think that whether the community will accept it upstream depends
> much about your commitment and the quality of the code, as well as how
> well you interact with the community during the reviews.
>
> Which port of WebKit is you currently using for testing?
>
> Cheers
> Kenneth
>
>
> On Wed, Oct 10, 2012 at 5:02 PM, Xian, Yuqiang <yuqiang.xian at intel.com> wrote:
>> Hi,
>>
>>
>>
>> As you may already know there’s a new x32 ABI – a 32-bit psABI for x86-64
>> with 32-bit pointer size. It tries to leverage the advantage of more
>> registers and IP relative addressing from x64 and the advantage of smaller
>> memory footprint from IA32. You can find more details of the x32 ABI here:
>> https://sites.google.com/site/x32abi/.
>>
>>
>>
>> The Linux kernel supports x32 since 3.4, and the commonly used development
>> tools and libraries are getting in the x32 support. Also more details about
>> current status is available in the above link.
>>
>>
>>
>> Now back to WebKit. In theory most part of the WebKit code should be fine
>> (or require less efforts) to support x32, if they’re pure C++ code and can
>> be compiled with the x32 toolchain. The major challenge is the JIT compiler
>> in the JavaScript engine (and the low level interpreter) and some
>> hand-written assembly code. So I’m currently working on enabling the x32
>> support of JavaScriptCore, the WebKit JavaScript engine, to try to remove
>> the major obstacle. My current status is that I have enabled the baseline
>> JIT, the DFG JIT and the Yarr JIT on x32 – it passes all the JavaScriptCore
>> tests and the 3 major benchmarks.
>>
>>
>>
>> I’m posting this message in order to seek for some advices on how we should
>> have our work shared to more people. I understand that it’s not very
>> appropriate to try to get it into current WebKit trunk considering current
>> x32 support status in major systems and the lack of maintenance in upstream,
>> but we want to keep it synchronized with the newest changes of the WebKit
>> code. So is it possible for us to maintain the code in a separate branch
>> hosted at the WebKit server?
>>
>>
>>
>> Any suggestions are appreciated.
>>
>>
>>
>> Thanks, -Yuqiang
>>
>>
>> _______________________________________________
>> webkit-dev mailing list
>> webkit-dev at lists.webkit.org
>> http://lists.webkit.org/mailman/listinfo/webkit-dev
>>
>
>
>
> --
> Kenneth Rohde Christiansen
> Senior Engineer, WebKit, Qt, EFL
> Phone  +45 4093 0598 / E-mail kenneth at webkit.org
>
> ﹆﹆﹆



-- 
Kenneth Rohde Christiansen
Senior Engineer, WebKit, Qt, EFL
Phone  +45 4093 0598 / E-mail kenneth at webkit.org

﹆﹆﹆