Summary:
`Status` is unfortunately heavily overloaded in practice. Things like
X11 define it as a macro. Best to just remove that possibility entirely.
Summary:
Expands on the previous support to enable formatted output, characters,
and checking basic iostat. We intentionally do not handle cases where
the descriptor is non-null as this is a non-trivial class that cannot
easily be shepherded across the wire.
Summary:
This PR provides the minimal support for Fortran I/O coming from a GPU
in OpenMP offloading. We use the same support the `libc` uses for its
printing through the RPC server. The helper functions `rpc::dispatch`
and `rpc::invoke` help make this mostly automatic.
Becaus Fortran I/O is not reentrant, the vast majority of complexity
comes from needing to stitch together calls from the GPU until they can
be executed all at once. This is needed not only because of the
limitations of recursive I/O, but without this the output would all be
interleaved because of the GPU's lock-step execution.
As such, the return values from the intermediate functions are
meaningless, all returning true. The final value is correct however. For
cookies we create a context pointer on the server to chain these
together.
Works on both my AMD and NVIDIA GPUs.
```fortran
program hello_gpu
implicit none
!$omp target teams num_teams(1)
!$omp parallel num_threads(2)
! Print strings
print *, "Hello from GPU"
!$omp end parallel
!$omp end target teams
end program hello_gpu
```
```console
> flang hello.f90 -O2 -fopenmp --offload-arch=gfx1030
> ./a.out
Hello from GPU
Hello from GPU
> flang hello.f90 -O2 -fopenmp --offload-arch=sm_89
> ./a.out
Hello from GPU
Hello from GPU
```
