Re: Fix Intel MIC 'mkoffload' for OpenMP 'requires' (was: [Patch] OpenMP: Move omp requires checks to libgomp)

[Tobias Burnus <tobias@codesourcery.com>]

Hi Thomas,

On 06.07.22 13:04, Thomas Schwinge wrote:
> On 2022-06-08T05:56:02+0200, Tobias Burnus <Tobias_Burnus@mentor.com> wrote:
>> PS: I have not fully tested the intelmic version.
> As part of my standard testing, I'm reporting that it got completely
> broken.  ;'-)

Interesting. Because intelmic-mkoffload.cc calls GOMP_offload_register
and not GOMP_offload_register_ver - and that call path should be unchanged.

However, I missed that I had an assert that GCC_OFFLOAD_OMP_REQUIRES_FILE is
set. - Thus, an alternative is to change that into an 'if'.

But I concur that updating intelmic-mkoffload.cc is nicer! Thanks!


Regarding:
> -! { dg-do link { target { offload_target_nvptx || offload_target_amdgcn } } }
> +! { dg-do link { target offloading_enabled } }
This patch looks wrong. We are not interested whether there is an offloading device
available or not - but whether the offloading compiler is running.

Those are completely independent. Obviously, offloading can be configured but not
being present. (That's the usual case for testing distro builds but also can
occur elsewhere.)
And also the reverse if possible - usually because of -foffload=... but when GCC is
configured with --enable-offload-defaulted, also other combinations are possible.


I think the proper check would be write and use an 'offload_target_any',
i.e. OFFLOAD_TARGET_NAMES= being present and nonempty.

Cf. check_effective_target_offload_target_nvptx / ..._amdgcn and
libgomp_check_effective_target_offload_target
in libgomp/testsuite/lib/libgomp.exp

Possible patch (untested):

# Return 1 if compiling for some offload target(s)
proc check_effective_target_offload_target_any { } {
     return [libgomp_check_effective_target_offload_target ""]
}

At least if I understand the following correctly, "" should work:
         return [string match "*:$target_name*:*" ":$gcc_offload_targets:"]


Thanks for taking care of the patch fallout!

Tobias

-----------------
Siemens Electronic Design Automation GmbH; Anschrift: Arnulfstraße 201, 80634 München; Gesellschaft mit beschränkter Haftung; Geschäftsführer: Thomas Heurung, Frank Thürauf; Sitz der Gesellschaft: München; Registergericht München, HRB 106955