Re: [Patch] Fortran: Update use_device_ptr for OpenMP 5.1 [PR105318]

[Jakub Jelinek <jakub@redhat.com>]

On Fri, Sep 30, 2022 at 12:41:19PM +0200, Tobias Burnus wrote:
> While has_device_addr has been implemented (in GCC 12), updating
> use_device_ptr for Fortran was missed.
> 
> This patch fixes it: Removing the restrictions and mapping to
> has_device_addr where applicable.
> 
> For use_device_ptr something similar was done, albeit I think
> this has no semantic effect.
> 
> And 'device(omp_initial_device)' printed a warning in Fortran.
> (BTW: C/C++ silently accepts any negative value.)

I think that is what the standard wants.
E.g. in 5.2 device Clause chapter, there is just
"If the device_num device-modifier is specified and target-offload-var is not mandatory,
device-description must evaluate to a conforming device number."
restriction, which is something that can't be checked at compile time,
you don't know if target-offload-var is mandatory or not.
>    if (omp_clauses->device)
> -    resolve_nonnegative_int_expr (omp_clauses->device, "DEVICE");
> +    {
> +      resolve_scalar_int_expr (omp_clauses->device, "DEVICE");
> +      /* omp_initial_device == 1, omp_invalid_device = -4 (in GCC).  */
> +      if (omp_clauses->device->expr_type == EXPR_CONSTANT
> +	  && omp_clauses->device->ts.type == BT_INTEGER
> +	  && mpz_cmp_si (omp_clauses->device->value.integer, -1) < 0
> +	  && mpz_cmp_si (omp_clauses->device->value.integer, -4) != 0)
> +	gfc_warning (0,
> +		     "INTEGER expression of DEVICE clause at %L must be non-"
> +		     "negative or omp_initial_device or omp_invalid_device",
> +		     &omp_clauses->device->where);
> +    }

So I think we should just resolve_scalar_int_expr and be done with that.

Otherwise LGTM.

	Jakub