Leverage CTAD with [MD]RangePolicy

[aprokop]

No description provided.

[aprokop]

I may indeed misunderstand some things. I do wonder why it compiled everywhere CPU, though, and not universally failed.

[dalg24]

I may indeed misunderstand some things. I do wonder why it compiled everywhere CPU, though, and not universally failed.

Because only one execution space was enabled and these types were equivalent/compatible.

[dalg24]

I stopped and didn't actually go through the rest of the changes. I expect you will find other occurrences if any

[aprokop]

I stopped and didn't actually go through the rest of the changes. I expect you will find other occurrences if any

Thank you. I used regex and should have been much more careful about the changes. I'm sorry.

[aprokop]

CUDA-11.1.1-NVCC build failed. Per usual, CTAD in CUDA versions pre 11.4 is really spotty. As mentioned in #974, it would make sense for us to update the CUDA-11.1 build, as it has been holding us back. Given that we have a CUDA-11.5.2-NVCC-CUDA-AWARE-MPI, I would propose switching 11.1 build to either 11.7 or 12.x.

SYCL build did not run.

Update: this reproducer fails on CUDA-11.1 with Kokkos 4.3:

#include <Kokkos_Core.hpp>

template <typename ExecutionSpace, typename ViewType>
void iota(ExecutionSpace const &space, ViewType const &v,
          typename ViewType::value_type value = 0)
{
  Kokkos::parallel_for(
      "ArborX::Algorithms::iota", Kokkos::RangePolicy(space, 0, v.extent(0)),
      KOKKOS_LAMBDA(int i) { v(i) = value + i; });
}

int main(int argc, char *argv[])
{
  Kokkos::ScopeGuard guard(argc, argv);

  Kokkos::View<int*> v("view", 10);
  iota(Kokkos::DefaultExecutionSpace{}, v);

  return EXIT_SUCCESS;
}

The failure:

<snip>/arborx/benchmarks/develop/develop.cpp: In instantiation of 'void iota(const ExecutionSpace&, const ViewType&, typename ViewType::value_type) [with ExecutionSpace = Kokkos::Cuda; ViewType = Kokkos::View<int*>; typename ViewType::value_type = int]':
<snip>/arborx/benchmarks/develop/develop.cpp:29:40:   required from here
<snip>/arborx/benchmarks/develop/develop.cpp:19:61: error: 'RangePolicy' was not declared in this scope; did you mean 'Kokkos::RangePolicy'?
   19 |   Kokkos::parallel_for(
      |                                                             ^
      |                                                  Kokkos::RangePolicy
/home/users/aprokop/local/opt/saturn/kokkos-4.3.1-cuda11.1/include/Kokkos_ExecPolicy.hpp:68:7: note: 'Kokkos::RangePolicy' declared here
   68 | class RangePolicy : public Impl::PolicyTraits<Properties...> {

It passes with added <ExecutionSpace> template to RangePolicy. It also passes with CUDA 11.5. So, some of the CTAD is definitely broken on CUDA 11.1 and probably others.

[aprokop]

Rebased.