[cfe-dev] GSoC 2018

[Mikhail Ramalho via cfe-dev]

Hi all,

Thank you for the feedback, George and Dominic.

I updated my proposal with an example, showing the encoded SMT formula for
the program and a brief explanation of the verification process. I used a
simplified program from a bug report in Bugzilla.

May I ask for some feedback in this section?

~

I addressed most of the comments, except for:

George: stretch goals are great, but for now I think it would be better to
focus on writing a considerably more detailed proposal on how and why the
main goal would be implemented.

I tried to explain the motivation in the Overview section, do you think a
motivation section would be better?

Regarding the how, I'll have another look in the BugReportVisitor and
update the proposal with a more concrete solution.

Thank you,


2018-03-21 17:54 GMT+00:00 George Karpenkov <ekarpenkov at apple.com>:

> Hi Mikhail,
>
> I’ve added some feedback.
> Overall, I think we should be aiming for something more low-level and
> concrete:
> adding examples with explanations would be a great improvement.
>
> Regards,
> George
>
>
> On Mar 21, 2018, at 10:12 AM, Mikhail Ramalho <mikhail.ramalho at gmail.com>
> wrote:
>
> Hi all,
>
> I've written a first draft of my proposal:
>
> https://docs.google.com/document/d/1-zNSv0l4WyoxYpJUAw8LFnQq
> _TY4AGjIpPu1VPkmO-g/edit?usp=sharing
>
> I've added a few comments in places I think need improvement.
>
> May I ask the community to have a look and give some feedback?
>
> Thank you,
>
>
> 2018-03-12 18:24 GMT+00:00 George Karpenkov <ekarpenkov at apple.com>:
>
>> Hi Mikhail,
>>
>> I’m assuming Dominic have answered your questions regarding the point (3).
>>
>> On point (1) I have recently sent an email on the list answering, I
>> believe, to essentially the same question:
>> http://lists.llvm.org/pipermail/cfe-dev/2018-March/057064.html
>>
>> (yes, unfortunately we do not have better archives, so messages might be
>> often hard to track)
>>
>> 2. I still don't quite understand how dynamic memory track works in the
>> analyzer, is the double checker expected to work for pointers and dynamic
>> memory as well? I'm assuming yes here and that Z3ConstraintManager might
>> need to be extended somehow (a plan will be added to the proposal).
>>
>>
>> I think here we should get the extra precision for free by adding a bug
>> reporter visitor, as described in the email thread I have linked to.
>>
>> Please feel free to ask any further questions, bug reporter visitors are
>> quite messy in the analyzer.
>>
>> Regards,
>> George
>>
>>
>> ~
>>
>> 3. This is a list of the TODOs in Z3ConstraintManager, from more
>> important to less important, in my opinion. I just want to know if the
>> analyzer's developers (and the project mentor) agree with this list, as it
>> might go into my proposal:
>>
>> 3.1. Don't assume nearest ties to even rounding mode: currently, only
>> rounding to even is supported, even if the code changes the rounding mode
>> using fesetround.
>>
>> 3.2. Don't add all the constraints, only the relevant ones: adding
>> unnecessary constraints will slowdown the solver.
>>
>> 3.3. Refactor doTypeConversion to use built-in conversion functions (Refactor
>> to Sema::FindCompositePointerType(), and Sema::CheckCompareOperands(); Refine
>> behavior for invalid type casts)
>> 3.4. Refactor doIntTypeConversion to use Sema::handleIntegerConversion()
>> 3.5. Refactor doFloatTypeConversion to use Sema::handleFloatConversion()
>>
>> I bundled this together because, although the conversion seems incomplete
>> (based on the comments), it's about removing duplicated code.
>>
>> 3.6. Refactor getAPSIntType(const llvm::APSInt &Int) const to put
>> elsewhere.
>>
>> ~
>>
>> Thank you,
>>
>>
>> 2018-02-24 1:03 GMT+00:00 Devin Coughlin <dcoughlin at apple.com>:
>>
>>>
>>>
>>> > On Feb 23, 2018, at 9:29 AM, Mikhail Ramalho via cfe-dev <
>>> cfe-dev at lists.llvm.org> wrote:
>>> >
>>> > I also have a question about the proposal. I understand that ideas
>>> about the project will be discussed in the mailing list. However, once
>>> that's settled and I write my first draft proposal, should I send it to the
>>> mailing list for discussion again or should I send it only to the mentor?
>>>
>>> Please make sure to keep email discussions on the mailing list rather
>>> than just personal email. This is a topic that members of the community
>>> will be interested in and will have valuable feedback on.
>>>
>>> Devin
>>>
>>>
>>
>>
>> --
>>
>> Mikhail Ramalho.
>> _______________________________________________
>> cfe-dev mailing list
>> cfe-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>>
>>
>>
>
>
> --
>
> Mikhail Ramalho.
>
>
>


-- 

Mikhail Ramalho.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20180322/49787432/attachment.html>