AMDGPU and 16B stack alignment

[Nick Desaulniers]

On Tue, Oct 15, 2019 at 11:05 AM Nick Desaulniers
<ndesaulniers at google.com> wrote:
>
> On Tue, Oct 15, 2019 at 12:19 AM Arnd Bergmann <arnd at arndb.de> wrote:
> >
> > On Tue, Oct 15, 2019 at 9:08 AM S, Shirish <sshankar at amd.com> wrote:
> > > On 10/15/2019 3:52 AM, Nick Desaulniers wrote:
> >
> > > My gcc build fails with below errors:
> > >
> > > dcn_calcs.c:1:0: error: -mpreferred-stack-boundary=3 is not between 4 and 12
> > >
> > > dcn_calc_math.c:1:0: error: -mpreferred-stack-boundary=3 is not between 4 and 12
>
> I was able to reproduce this failure on pre-7.1 versions of GCC.  It
> seems that when:
> 1. code is using doubles
> 2. setting -mpreferred-stack-boundary=3 -mno-sse2, ie. 8B stack alignment
> than GCC produces that error:
> https://godbolt.org/z/7T8nbH
>

Also, I suspect that very error solves the mystery of "why was 16B
stack alignment ever specified?"
-- 
Thanks,
~Nick Desaulniers