http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43147
Marc Glisse <marc.glisse at normalesup dot org> changed:
What |Removed |Added
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CC| |marc.glisse at normalesup
| |dot org
--- Comment #4 from Marc Glisse <marc.glisse at normalesup dot org> 2011-10-23
08:40:04 UTC ---
Apart from combining 2 shuffles, I would expect the set and the shuffle to be
combined in Comment 1. I was going to report the following, but it already
appears in this bug:
__m128d f(double d){
__m128d x=_mm_setr_pd(-d,d);
return _mm_shuffle_pd(x,x,1);
}
movsd .LC0(%rip), %xmm1
xorpd %xmm0, %xmm1
movapd %xmm1, %xmm2
unpcklpd %xmm0, %xmm2
movapd %xmm2, %xmm0
shufpd $1, %xmm2, %xmm0
some extra moves, as usual, and a shuffle that could be combined with the
unpack.
(obviously we don't write such code, it is only after inlining that it looks
that way)
