Hello Aldy,
Thank you for responding. Please see my answers to your questions
embedded below.
If this is OK with everyone, I will start sending patches to
gcc-patches mailing list soon.
Thanks,
Balaji V. Iyer.
>-----Original Message-----
>From: Aldy Hernandez [mailto:al...@redhat.com]
>Sent: Tuesday, September 04, 2012 6:24 PM
>To: Iyer, Balaji V
>Cc: 'gcc@gcc.gnu.org'; Jeff Law; r...@redhat.com
>Subject: Re: Merging Cilk Plus into GCC Trunk
>
>On 08/30/12 15:39, Iyer, Balaji V wrote:
>> Hello Everyone,
>> The Cilk-Plus branch is feature-complete. Programs using Cilk Plus
>constructs get great performance on vector and multicore hardware. Programs
>that don't use the new language features (enabled by a -fcilkplus flag) see no
>change. For details please see http://cilkplus.org.
>> It's time to promote the branch into mainline. Cilk Plus branch is
>> stable
>and there is no unexpected failures with respect to the trunk in regression
>testsuites. Most of the changes are in the front and middle-end. Since it
>involves
>many changes, I plan to break it up into individual patches (listed below),
>each of
>which adds a new, complete capability. Later patches sometimes use the
>functionality added by the previous one. For example, Elemental functions for
>C++ will depend on some of the common routines used in C patch:
>
>Hi Iyer.
>
>Thank you for all your work on this.
>
>Perhaps it is of interest to note (IIRC), that the language extensions have
>been
>proposed for inclusion in the next OpenMP version??
Cilk Plus has been proposed for inclusion in the next C++ standard.
>
>I can't speak for the rest of the community, but I think items 1-12 are useful
>for
>GCC (elemental functions, SIMD annotations, and array notations for C/C++),
>regardless of any language extensions. Perhaps you could provide examples on
>these as a start?
>
I was planning to provide an example for elemental function, array notations
and SIMD annotations with each patch. Is that good enough?
>
>Regarding the SIMD annotations, I find the "vector" attribute somewhat
>ambiguous, or prone to confusing users, so perhaps we could come up with a
>better name?
The keyword "vector" is used by the Intel Compiler and we would like them both
to be compatible. Jakub at Cauldron did mention that vector keyword is used in
Power PC and thus can potentially cause some interference. I configured the
Cilk Plus branch for Power PC and I compiled both elemental functions and
PowerPC programs that use the vector keyword. They both seem to work correctly.
>
>Over all, I don't see why this can't be included as an experimental feature
>like
>OpenMP, transactional memory, etc, especially if it's relatively self
>contained and
>doesn't affected the non cilkplus code path too much.
>
>Anyone have further thoughts on this, especially global maintainers :)?
>Aldy
>
>>
>> 1. Elemental functions for C.
>> 2. Regression tests for elemental functions for C.
>> 3. Elemental functions for C++.
>> 4. Regression tests for elemental functions for C++.
>> 5. SIMD annotations for C.
>> 6. Regression tests for SIMD annotations for C.
>> 7. SIMD annotations for C++.
>> 8. Regression tests for SIMD annotations for C++.
>> 9. Array notations for C.
>> 10. Regression tests for Array notations for C.
>> 11. Array Notations for C++.
>> 12. Regression tests for Array Notations for C++.
>> 13. The Cilk Runtime library -- It is a separate directory without any
>> changes to
>compiler source.
>> 14. Cilk Keywords (_Cilk_spawn and _Cilk_sync) for C.
>> 15. Regression tests _Cilk_spawn and _Cilk_sync for C.
>> 16. Cilk Keywords (_Cilk_spawn and _Cilk_sync) for C++.
>> 17. Regression tests _Cilk_spawn and _Cilk_sync for C++.
>> 18. Cilk Keywords (_Cilk_for) for C.
>> 19. _Cilk_for Regression tests for C.
>> 20. Cilk Keywords (_Cilk_for) for C++.
>> 21. _Cilk_for Regression tests for C++.
>> 22. Documentation about Cilk Plus into GCC documents.
>>
>> If there is a more effective way to merge our changes to the trunk, I am open
>to suggestions.
>>
>> Thanking You,
>>
>> Yours Sincerely,
>>
>> Balaji V. Iyer.
>>
