[Openmp-dev] Offloading application build with a Trunk Debug Clang is so slow

[Itaru Kitayama via Openmp-dev]

The Clang at this commit:
commit 1c49553c19a7044fbbf4528b732926f19f210e54
Author: Bjorn Pettersson <bjorn.a.pettersson at ericsson.com>
Date:   Thu Dec 12 20:51:13 2019 +0100
[kitayama1 at juron1-adm pcp0151]$ time clang++ -g -fopenmp
-fopenmp-targets=nvptx64 mini.cpp

real 0m2.344s
user 0m2.231s
sys 0m0.049s
Release Clang 9
[[kitayama1 at juron1-adm pcp0151]$ time clang++ -g -fopenmp
-fopenmp-targets=nvptx64 mini.cpp

real 0m0.693s
user 0m0.533s
sys 0m0.047s

On Thu, Dec 19, 2019 at 5:32 AM Jon Chesterfield <
jonathanchesterfield at gmail.com> wrote:

> Ah, OK. In that case I still suspect a regression in clang, as opposed to
> a change in the library. Does the compile time remain very slow if you roll
> deviceRTL back by a few days?
>
> On Wed, Dec 18, 2019 at 8:30 PM Itaru Kitayama <itaru.kitayama at gmail.com>
> wrote:
>
>> Sorry, of course it should include this #pragma
>> omp target parallel for for(;;) {}. My local Debug Clang is updated
>> daily, so the tool chain is pretty much up to date.
>>
>> On Thu, Dec 19, 2019 at 5:24 Jon Chesterfield <
>> jonathanchesterfield at gmail.com> wrote:
>>
>>> On Wed, Dec 18, 2019 at 8:13 PM Itaru Kitayama <itaru.kitayama at gmail.com>
>>> wrote:
>>>
>>>> The app build time increases can be reproduced with a simple int main()
>>>> {} code.
>>>>
>>>
>>> I thought the problem was with the compile time of deviceRTL.
>>>
>>> If you're compiling int main() {}, then there's no openmp involved, so
>>> that seems out of scope for this list.
>>>
>>>
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