If I understand correctly, a do concurrent construct does not necessarily imply that the code inside the block will run in parallel, because (for instance) the compiler might estimate that the compute task does not justify the overhead of parallelization. On the other hand, I have doubts about what…

Thanks for the hint. Yes, the paper that I cited in my first post has a detailed comparison of ifort, nvfortran and gfortran, and NVIDIA’s compiler does indeed do a good job at parallelizing do concurrent constructs. By default, I use gfortran, so (more or less implicitly) I am looking for the appro…

Thanks, very helpfull suggestion. I have just started playing with the -fopt-info flag. :slight_smile:

I summarized some do concurrent related information in this thread and thought it is worth reposting here: Multi-threaded do concurrent (CPU) Compiler Parallel flag Information Number of threads Underlying implementation gfortran -ftree-parallelize-loops=n -fopt-info-loop using the paralle…

1. The do concurrent has nothing to do with parallel flags for intel. It uses OpenMP under the hood and the compiler flag is always /Qopenmp for windows for both ifort and ifx. 2. I think it is same for gfortran and -fopenmp compiler flag is used for do concurrent. 3.A few months ago i asked …

[image] Shahid: 1. The do concurrent has nothing to do with parallel flags for intel. Concerning the Intel Fortran Compiler Classic (ifort), this Intel thread from 2015 stated: DO CONCURRENT allows the compiler to ignore any potential dependencies between iterations and to execute the loop…

I just verified on amdflang for AMDGPUs that you can use -fopenmp --offload-arch=gfx90a -fdo-concurrent-to-openmp=device to offload do concurrent to devices!

When you say amdflang, what exact compiler are you talking about? The AMD next gen fortran compiler ? If so, which ‘drop’. I tried a pre-release version of drop 6.0.0 back in April which seriously struggled with openMP offload (even a basic reduction). I was too scared to try do-concurrent at the tim…

https://repo.radeon.com/rocm/misc/flang/rocm-afar-8248-drop-7.0.0-sles.tar.bz2 This drop

We have added first support this in that drop. Please note, that not everything is working yet, e.g., locality specifiers might not be supported yet. Also, polymorphic types cannot be used, because the OpenMP API does not yet support to transfer and use them on a target device. If you’re playing …

DO CONCURRENT: compiler flags to enable parallelization

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Shahid January 3, 2024, 2:46pm 9

This is very interesting.

I will check my codes again and possibly get back.

Gcc/gfortran 16 released

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DO CONCURRENT: compiler flags to enable parallelization

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