On Thu, Dec 5, 2013 at 5:17 AM, Tejas Belagod <tbela...@arm.com> wrote: > H.J. Lu wrote: >> >> On Wed, Dec 4, 2013 at 9:29 AM, Jeff Law <l...@redhat.com> wrote: >>> >>> On 12/04/13 09:14, H.J. Lu wrote: >>> >>>>> + >>>>> +/* { dg-final { scan-rtl-dump "deleting noop move" "combine" { target >>>>> aarch64*-*-* } } } */ >>>> >>>> >>>> Any particular reason why it doesn't work for x86? >>> >>> I don't think so. I'm pretty sure Tejas is focused on ARM platforms for >>> the >>> obvious reason. >>> >> >> Then please add "i?86-*-* x86_64-*-*". > > > Hi, > > I tried this test on x86_64. Though the same RTL gets generated > > (set (reg:Sf) (vec_select:SF (reg:V4Sf) (parallel [const 0])) > > for -msse2, this optimization does not seem to trigger. Only later in a > post-reload-split does it get eliminated to something like > > (set (reg:SF 21 xmm0) (reg:SF 21 xmm0)) > > I suspect simplify_subreg_regno () may not be returning what we want here - > sorry, I don't know enough about x86 to debug deeper.
Kirill, can you take a look why it doesn't work for x86? > I could either keep this test case as is or if you could give it a quick > look to see why it does not trigger, it would be useful to add x86 to this > test. > > Thanks, > Tejas. > -- H.J.