iqk_mul_mat: fix q8_0

I was happily using _mm256_packs_epi32() to pack the
q8_0 x q8_0 dot products back to int16_t, and getting useful
results. But theoretically this can overflow, so it is
better to use _mm256_unpacklo_ and _mm256_unpackhi_ to combine
the 4 dot products using int32_t additions. This is (almost)
as fast, unlike _mm256_hadd_epi32(), which seems excessively
slow on the Ryzen-7950X.

0 files changed, 0 insertions, 0 deletions