[Openmp-dev] Target architecture does not support unified addressing

[Itaru Kitayama via Openmp-dev]

Doru - can you jump in this discussion?

On Wed, Nov 6, 2019 at 8:17 AM Alexey Bataev <a.bataev at outlook.com> wrote:

> Better to ask Doru Bercea who worked on this feature.
>
> Best regards,
> Alexey Bataev
>
> 5 нояб. 2019 г., в 18:04, Itaru Kitayama <itaru.kitayama at gmail.com>
> написал(а):
>
> 
> Can you say briefly as to why SM60, while it is capable of handing unified
> addresses, is not supported in Clang?
>
> On Wed, Nov 6, 2019 at 7:56 AM Alexey Bataev <a.bataev at outlook.com> wrote:
>
>> Yes, it is enforced in clang.
>>
>> Best regards,
>> Alexey Bataev
>>
>> 5 нояб. 2019 г., в 17:38, Itaru Kitayama <itaru.kitayama at gmail.com>
>> написал(а):
>>
>> 
>> Thank you, Alexey. Now I am seeing:
>>
>> $ clang++ -fopenmp -fopenmp-targets=nvptx64 tmp.cpp
>> tmp.cpp:1:22: error: Target architecture sm_60 does not support unified
>> addressing
>> #pragma omp requires unified_shared_memory
>>                      ^
>> 1 error generated.
>>
>> P100 is a SM60 device, but supports unified memory. Is a requirement
>> sm_70 equals or greater
>> enforced in Clang?
>>
>> On Wed, Nov 6, 2019 at 5:07 AM Alexey Bataev <a.bataev at outlook.com>
>> wrote:
>>
>>> Most probably, you use default architecture, i.e. sm_35. You need to
>>> build clang with sm_35, sm_70, ... supported archs. Plus, your system must
>>> support unified memory.
>>>
>>> I updated error message in the compiler, now it says what target
>>> architecture you use .
>>>
>>> -------------
>>> Best regards,
>>> Alexey Bataev
>>>
>>> 05.11.2019 3:01 PM, Itaru Kitayama пишет:
>>>
>>> I’ve been building trunk Clang locally targeting the P100 device
>>> attached to Host. Should I check the tool chain?
>>>
>>> On Tue, Nov 5, 2019 at 23:47 Alexey Bataev <a.bataev at outlook.com> wrote:
>>>
>>>> You're building you code for the architecture that does not support
>>>> unified memory, say sm_35. Unified memory only supported for architectures
>>>> >= sm_70.
>>>>
>>>> -------------
>>>> Best regards,
>>>> Alexey Bataev
>>>>
>>>> 05.11.2019 3:16 AM, Itaru Kitayama via Openmp-dev пишет:
>>>>
>>>> Hi,
>>>> Using a pragma like below:
>>>>
>>>> $ cat tmp.cpp
>>>> #pragma omp requires unified_shared_memory
>>>>
>>>> int main() {
>>>> }
>>>>
>>>> produces en error on a POWER8 based system with P100 devices (that
>>>> support unified memory).
>>>>
>>>> $ clang++ -fopenmp -fopenmp-targets=nvptx64 tmp.cpp
>>>> tmp.cpp:1:22: error: Target architecture does not support unified
>>>> addressing
>>>> #pragma omp requires unified_shared_memory
>>>>                      ^
>>>> 1 error generated.
>>>>
>>>> The Clang is locally and natively built with the appropriate
>>>> capability, so
>>>> what does this mean?
>>>>
>>>>
>>>> _______________________________________________
>>>> Openmp-dev mailing listOpenmp-dev at lists.llvm.orghttps://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev
>>>>
>>>>
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