Ping x 2

Ramana

On Thu, 17 Nov 2022, 20:15 Ramana Radhakrishnan, <ramana.gcc@googlemail.com>
wrote:

> On Fri, Nov 11, 2022 at 9:50 PM Ramana Radhakrishnan
> <ramana.gcc@googlemail.com> wrote:
> >
> > On Thu, Nov 10, 2022 at 7:46 PM Ramana Radhakrishnan
> > <ramana.gcc@googlemail.com> wrote:
> > >
> > > On Thu, Nov 10, 2022 at 6:03 PM Richard Earnshaw
> > > <Richard.Earnshaw@foss.arm.com> wrote:
> > > >
> > > >
> > > >
> > > > On 10/11/2022 17:21, Richard Earnshaw via Gcc-patches wrote:
> > > > >
> > > > >
> > > > > On 08/11/2022 18:20, Ramana Radhakrishnan via Gcc-patches wrote:
> > > > >> PR92999 is a case where the VFP calling convention does not
> allocate
> > > > >> enough FP registers for a homogenous aggregate containing FP16
> values.
> > > > >> I believe this is the complete fix but would appreciate another
> set of
> > > > >> eyes on this.
> > > > >>
> > > > >> Could I get a hand with a regression test run on an armhf
> environment
> > > > >> while I fix my environment ?
> > > > >>
> > > > >> gcc/ChangeLog:
> > > > >>
> > > > >> PR target/92999
> > > > >> *  config/arm/arm.c (aapcs_vfp_allocate_return_reg): Adjust to
> handle
> > > > >> aggregates with elements smaller than SFmode.
> > > > >>
> > > > >> gcc/testsuite/ChangeLog:
> > > > >>
> > > > >> * gcc.target/arm/pr92999.c: New test.
> > > > >>
> > > > >>
> > > > >> Thanks,
> > > > >> Ramana
> > > > >>
> > > > >> Signed-off-by: Ramana Radhakrishnan <ramana.gcc@gmail.com>
> > > > >
> > > > > I'm not sure about this.  The AAPCS does not mention a base type
> of a
> > > > > half-precision FP type as an appropriate homogeneous aggregate for
> using
> > > > > VFP registers for either calling or returning.
> > >
> > > Ooh interesting, thanks for taking a look and poking at the AAPCS and
> > > that's a good catch. BF16 should also have the same behaviour as FP16
> > > , I suspect ?
> >
> > I suspect I got caught out by the definition of the Homogenous
> > aggregate from Section 5.3.5
> > ((
> https://github.com/ARM-software/abi-aa/blob/2982a9f3b512a5bfdc9e3fea5d3b298f9165c36b/aapcs32/aapcs32.rst#homogeneous-aggregates
> )
> > which simply suggests it's an aggregate of fundamental types which
> > lists half precision floating point .
> >
> > FTR, ideally I should have read 7.1.2.1
> >
> https://github.com/ARM-software/abi-aa/blob/2982a9f3b512a5bfdc9e3fea5d3b298f9165c36b/aapcs32/aapcs32.rst#procedure-calling
> )
> > :)
> >
> >
> >
> > >
> > > > >
> > > > > So perhaps the bug is that we try to treat this as a homogeneous
> > > > > aggregate at all.
> > >
> > > Yep I agree - I'll take a look again tomorrow and see if I can get a
> fix.
> > >
> > > (And thanks Alex for the test run, I might trouble you again while I
> > > still (slowly) get some of my boards back up)
> >
> >
> > and as promised take 2. I'd really prefer another review on this one
> > to see if I've not missed anything in the cases below.
>
> Ping  ?
>
> Ramana
>
> >
> > regards
> > Ramana
> >
> >
> > >
> > > regards,
> > > Ramana
> > >
> > >
> > > >
> > > > R.
>