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Re: PR83004: Accidental change to pr81136.c for VECTOR_BITS==128


On Wed, Nov 22, 2017 at 02:17:59PM +0000, Richard Sandiford wrote:
> Jakub Jelinek <jakub@redhat.com> writes:
> > On Wed, Nov 22, 2017 at 02:51:09PM +0100, Richard Biener wrote:
> >> On Wed, Nov 22, 2017 at 10:30 AM, Richard Sandiford
> >> <richard.sandiford@linaro.org> wrote:
> >> > r254589 was supposed to leave tests unchanged for the default setting
> >> > of VECTOR_BITS, but I must have got my sums wrong on pr81136.c.
> >> > Sorry for the breakage.
> >> >
> >> > Tested on aarch64-linux-gnu, x86_64-linux-gnu and powerpc64le-linux-gnu,
> >> > OK to install?
> >> 
> >> Ok.
> >
> > That will still FAIL e.g. with -march=skylake-avx512 or -march=knl
> > (at least when not preferring 256 or 128 bit vectors), those would need
> > ALIGNMENT 64.
> 
> Yeah, the real fix for AVX512 is to define VECTOR_BITS.  And I'd have
> thought even AVX2 would need to define it to get clean results on other
> tests.  But the patch that introduced VECTOR_BITS just wasn't supposed
> to be changing the default behaviour in the way that I'd accidentally
> done here.
> 
> Do you know what the vect.exp results are like for 256-bit and 512-bit
> vectors on x86_64?  Like I said in the PR, I was surprised we were the

Dunno, but can try it for -march=haswell easily (or we could look up
gcc-testresults).  I think some of the Intel folks are surely testing
regularly with --with-arch=haswell configured compiler, judging from many
bugreports about tests from the testsuite that only fail with -march=haswell.

	Jakub


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