Re: [RFC][nvptx, libgomp] Add 128-bit atomic support

[Tobias Burnus <tobias@codesourcery.com>]

On 9/2/20 12:22 PM, Tom de Vries wrote:

> Tobias, can you try on powerpc?

Testcase now compiles and runs w/o error message.

On 9/2/20 12:44 PM, Jakub Jelinek wrote:

> I guess the normal answer would be use libatomic, but it isn't ported for
> nvptx.
> I guess at least temporarily this is ok,though I'm wondering why
> you need __sync_*_16 rather than __atomic_*_16, or perhaps both __sync_* and
> __atomic_*.
>
> What happens if you try
> unsigned __int128 v;

...

I had to change "unsigned __int128" and "unsigned __int128v" to
"__uint128_t" and "expected" to "exp". Result without offloading
configured on x86-64-gnu-linux:

aotmic.c:(.text+0x84): undefined reference to `__atomic_fetch_add_16'
/usr/bin/ld: aotmic.c:(.text+0xa3): undefined reference to `__atomic_fetch_add_16'
/usr/bin/ld: aotmic.c:(.text+0xda): undefined reference to `__atomic_compare_exchange_16'

And on PowerPC with nvptx (without the RFC patch):

atomic.c: In function 'main._omp_fn.0':
atomic.c:6:11: internal compiler error: in write_fn_proto, at config/nvptx/nvptx.c:913
     6 |   #pragma omp target
       |           ^

Tobias

-----------------
Mentor Graphics (Deutschland) GmbH, Arnulfstraße 201, 80634 München / Germany
Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, Alexander Walter