Bug#836844: eigen3: autopkgtests fail on ppc64el

[TFAUCK]

On Thu, 1 Dec 2016 16:15:50 +0100 Roger <rogfauck at free.fr> wrote:
> On Sun, 13 Nov 2016 18:04:28 +0200 Graham Inggs <ginggs at debian.org> wrote:
> > Control: reopen -1
> > 
> > I've just checked eigen3 3.3.0-1 on plummer.debian.org, and it still outputs
> > 
> > forceMatrix*axisMatrix: -1  0  0
> >  0 -2  0
> >  0  0 -3
> > 
> > 
> I have checked with current dev. tree and problem remains
> I have tried compiler g++-4.9 and g++-5 and g++-6 and all are providing
> same error on ppc64le
> On x86_64 using g++-5 there is no error.
> 
> 
Digging through the code, I found the difference
src/Core/functors/BinaryFunctors.h:89
	{ return internal::pmul(a,b); }

on x86_64 it calls at line 192
extern __inline __m128 __attribute__((__gnu_inline__, __always_inline__,
__artificial__))  _mm_mul_ps (__m128 __A, __m128 __B)
                          │    {
                                        return (__m128) ((__v4sf)__A *
(__v4sf)__B);
}


when on ppc64le pmul() calls
/usr/include/eigen3/Eigen/src/Core/arch/AltiVec/PacketMath.h:361
	return vec_madd(a,b, p4f_ZERO);

so I suspect there is something there


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thf - Thierry Fauck - tfauck at free.fr>
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