Re: [PATCH PR81228][AARCH64] Fix ICE by adding LTGT in vec_cmp<mode><v_int_equiv>

[Sudakshina Das <sudi dot das at arm dot com>]

On 14/12/17 10:38, Sudakshina Das wrote:
> Hi
>
> On 13/12/17 16:56, James Greenhalgh wrote:
> > On Wed, Dec 13, 2017 at 04:45:33PM +0000, Sudi Das wrote:
> > > On 13/12/17 16:42, Sudakshina Das wrote:
> > > > Hi
> > > >
> > > > This patch is a follow up to the existing discussions on
> > > > https://gcc.gnu.org/ml/gcc-patches/2017-07/msg01904.html
> > > > Bin had earlier submitted a patch to fix the ICE that occurs because of
> > > > the missing LTGT in aarch64-simd.md.
> > > > That discussion opened up a new bug report PR81647 for an inconsistent
> > > > behavior.
> > > >
> > > > As discussed earlier on the gcc-patches discussion and on the bug
> > > > report, PR81647 was occurring because of how UNEQ was handled in
> > > > aarch64-simd.md rather than LTGT. Since __builtin_islessgreater is
> > > > guaranteed to not give an FP exception but LTGT might,
> > > > __builtin_islessgreater gets converted to ~UNEQ very early on in
> > > > fold_builtin_unordered_cmp. Thus I will post a separate patch for
> > > > correcting how UNEQ and other unordered comparisons are handled in
> > > > aarch64-simd.md.
> > > >
> > > > This patch is only adding the missing LTGT to plug the ICE.
> > > >
> > > > Testing done: Checked for regressions on bootstrapped
> > > > aarch64-none-linux-gnu and added a new compile time test case that 
> > > > gives
> > > > out LTGT to make sure it doesn't ICE.
> > > >
> > > > Is this ok for trunk?
> >
> > OK.
> >
> > Thanks,
> > James
>
> Thanks for the review.
> Committed as r255625.
> I think this needs a back-port as well to gcc-7-branch. Is that ok?
>
> Sudi

Backport Ping!

Sudi