src/qu8-igemm/4x4c2-minmax-gemmlowp-sse2.c - platform/external/XNNPACK - Gitiles

 // Copyright (c) Facebook, Inc. and its affiliates.
 // All rights reserved.
 //
 // Copyright 2019 Google LLC
 //
 // This source code is licensed under the BSD-style license found in the
 // LICENSE file in the root directory of this source tree.

 #include <assert.h>

 #include <immintrin.h>

 #include <xnnpack/igemm.h>
 #include <xnnpack/math.h>


 void xnn_qu8_igemm_minmax_gemmlowp_ukernel_4x4c2__sse2(
     size_t mr,
     size_t nc,
     size_t kc,
     size_t ks,
     const uint8_t** restrict a,
     const void* restrict w,
     uint8_t* restrict c,
     size_t cm_stride,
     size_t cn_stride,
     size_t a_offset,
     const uint8_t* zero,
     const union xnn_qu8_conv_minmax_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_DISABLE_TSAN
 {
   assert(mr != 0);
   assert(mr <= 4);
   assert(nc != 0);
   assert(kc != 0);
   assert(ks != 0);
   assert(ks % (4 * sizeof(void*)) == 0);
   assert(a_offset % sizeof(int8_t) == 0);
   assert(a != NULL);
   assert(w != NULL);
   assert(c != NULL);

   kc = round_up_po2(kc, 2);
   uint8_t* c0 = c;
   uint8_t* c1 = (uint8_t*) ((uintptr_t) c0 + cm_stride);
   if XNN_UNPREDICTABLE(mr < 2) {
     c1 = c0;
   }
   uint8_t* c2 = (uint8_t*) ((uintptr_t) c1 + cm_stride);
   if XNN_UNPREDICTABLE(mr <= 2) {
     c2 = c1;
   }
   uint8_t* c3 = (uint8_t*) ((uintptr_t) c2 + cm_stride);
   if (mr != 4) {
     c3 = c2;
   }

   const __m128i vb_zero_point = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.kernel_zero_point);

   do {
     __m128i vacc0x0123 = _mm_loadu_si128((const __m128i*) w);
     __m128i vacc1x0123 = vacc0x0123;
     __m128i vacc2x0123 = vacc0x0123;
     __m128i vacc3x0123 = vacc0x0123;
     w = (const void*) ((uintptr_t) w + 16);

     const __m128i vzero = _mm_setzero_si128();
     size_t p = ks;
     do {
       const uint8_t* restrict a0 = a[0];
       if XNN_UNPREDICTABLE(a0 != zero) {
         a0 = (const uint8_t*) ((uintptr_t) a0 + a_offset);
       }
       const uint8_t* restrict a1 = a[1];
       if XNN_UNPREDICTABLE(a1 != zero) {
         a1 = (const uint8_t*) ((uintptr_t) a1 + a_offset);
       }
       const uint8_t* restrict a2 = a[2];
       if XNN_UNPREDICTABLE(a2 != zero) {
         a2 = (const uint8_t*) ((uintptr_t) a2 + a_offset);
       }
       const uint8_t* restrict a3 = a[3];
       if XNN_UNPREDICTABLE(a3 != zero) {
         a3 = (const uint8_t*) ((uintptr_t) a3 + a_offset);
       }
       a += 4;

       size_t k = kc;
       while (k >= 8 * sizeof(uint8_t)) {
         const __m128i va0 = _mm_loadl_epi64((const __m128i*) a0);
         const __m128i vxa0 = _mm_unpacklo_epi8(va0, vzero);
         a0 += 8;
         const __m128i va1 = _mm_loadl_epi64((const __m128i*) a1);
         const __m128i vxa1 = _mm_unpacklo_epi8(va1, vzero);
         a1 += 8;
         const __m128i va2 = _mm_loadl_epi64((const __m128i*) a2);
         const __m128i vxa2 = _mm_unpacklo_epi8(va2, vzero);
         a2 += 8;
         const __m128i va3 = _mm_loadl_epi64((const __m128i*) a3);
         const __m128i vxa3 = _mm_unpacklo_epi8(va3, vzero);
         a3 += 8;

         const __m128i vb0 = _mm_loadl_epi64((const __m128i*) w);
         const __m128i vxb0 = _mm_sub_epi16(_mm_unpacklo_epi8(vb0, vzero), vb_zero_point);
         vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));

         const __m128i vb1 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 8));
         const __m128i vxb1 = _mm_sub_epi16(_mm_unpacklo_epi8(vb1, vzero), vb_zero_point);
         vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
         vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
         vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
         vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));

         const __m128i vb2 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 16));
         const __m128i vxb2 = _mm_sub_epi16(_mm_unpacklo_epi8(vb2, vzero), vb_zero_point);
         vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
         vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
         vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
         vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));

         const __m128i vb3 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 24));
         const __m128i vxb3 = _mm_sub_epi16(_mm_unpacklo_epi8(vb3, vzero), vb_zero_point);
         vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
         vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
         vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
         vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));

         w = (void*) ((uintptr_t) w + 32);

         k -= 8 * sizeof(uint8_t);
       }
       if (k != 0) {
         const __m128i va0 = _mm_loadl_epi64((const __m128i*) a0);
         const __m128i vxa0 = _mm_unpacklo_epi8(va0, vzero);
         const __m128i va1 = _mm_loadl_epi64((const __m128i*) a1);
         const __m128i vxa1 = _mm_unpacklo_epi8(va1, vzero);
         const __m128i va2 = _mm_loadl_epi64((const __m128i*) a2);
         const __m128i vxa2 = _mm_unpacklo_epi8(va2, vzero);
         const __m128i va3 = _mm_loadl_epi64((const __m128i*) a3);
         const __m128i vxa3 = _mm_unpacklo_epi8(va3, vzero);

         const __m128i vb0 = _mm_loadl_epi64((const __m128i*) w);
         const __m128i vxb0 = _mm_sub_epi16(_mm_unpacklo_epi8(vb0, vzero), vb_zero_point);
         w = (void*) ((uintptr_t) w + 8);

         vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
         vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));

         if (k > 2 * sizeof(uint8_t)) {
           const __m128i vb1 = _mm_loadl_epi64((const __m128i*) w);
           const __m128i vxb1 = _mm_sub_epi16(_mm_unpacklo_epi8(vb1, vzero), vb_zero_point);
           w = (void*) ((uintptr_t) w + 8);

           vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
           vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
           vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
           vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));

           if (k > 4 * sizeof(uint8_t)) {
             const __m128i vb2 = _mm_loadl_epi64((const __m128i*) w);
             const __m128i vxb2 = _mm_sub_epi16(_mm_unpacklo_epi8(vb2, vzero), vb_zero_point);
             w = (void*) ((uintptr_t) w + 8);

             vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
             vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
             vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
             vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
           }
         }
       }
       p -= 4 * sizeof(void*);
     } while (p != 0);

     const __m128i vmultiplier = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.multiplier);
     const __m128i vrounding = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.rounding);

     const __m128i vnmask0x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc0x0123);
     const __m128i vnmask1x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc1x0123);
     const __m128i vnmask2x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc2x0123);
     const __m128i vnmask3x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc3x0123);

     const __m128i vabsacc0x0123 = _mm_sub_epi32(_mm_xor_si128(vacc0x0123, vnmask0x0123), vnmask0x0123);
     const __m128i vabsacc1x0123 = _mm_sub_epi32(_mm_xor_si128(vacc1x0123, vnmask1x0123), vnmask1x0123);
     const __m128i vabsacc2x0123 = _mm_sub_epi32(_mm_xor_si128(vacc2x0123, vnmask2x0123), vnmask2x0123);
     const __m128i vabsacc3x0123 = _mm_sub_epi32(_mm_xor_si128(vacc3x0123, vnmask3x0123), vnmask3x0123);

     const __m128i vabsacc0x1032 = _mm_shuffle_epi32(vabsacc0x0123, _MM_SHUFFLE(2, 3, 0, 1));
     const __m128i vabsacc1x1032 = _mm_shuffle_epi32(vabsacc1x0123, _MM_SHUFFLE(2, 3, 0, 1));
     const __m128i vabsacc2x1032 = _mm_shuffle_epi32(vabsacc2x0123, _MM_SHUFFLE(2, 3, 0, 1));
     const __m128i vabsacc3x1032 = _mm_shuffle_epi32(vabsacc3x0123, _MM_SHUFFLE(2, 3, 0, 1));

     const __m128i vabsprod0x02 = _mm_mul_epu32(vabsacc0x0123, vmultiplier);
     const __m128i vabsprod1x02 = _mm_mul_epu32(vabsacc1x0123, vmultiplier);
     const __m128i vabsprod2x02 = _mm_mul_epu32(vabsacc2x0123, vmultiplier);
     const __m128i vabsprod3x02 = _mm_mul_epu32(vabsacc3x0123, vmultiplier);

     const __m128i vnmask0x02 = _mm_shuffle_epi32(vnmask0x0123, _MM_SHUFFLE(2, 2, 0, 0));
     const __m128i vnmask1x02 = _mm_shuffle_epi32(vnmask1x0123, _MM_SHUFFLE(2, 2, 0, 0));
     const __m128i vnmask2x02 = _mm_shuffle_epi32(vnmask2x0123, _MM_SHUFFLE(2, 2, 0, 0));
     const __m128i vnmask3x02 = _mm_shuffle_epi32(vnmask3x0123, _MM_SHUFFLE(2, 2, 0, 0));

     const __m128i vprod0x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod0x02, vnmask0x02), vnmask0x02);
     const __m128i vprod1x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod1x02, vnmask1x02), vnmask1x02);
     const __m128i vprod2x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod2x02, vnmask2x02), vnmask2x02);
     const __m128i vprod3x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod3x02, vnmask3x02), vnmask3x02);

     const __m128i vq31prod0x02 = _mm_srli_epi64(_mm_add_epi64(vprod0x02, vrounding), 31);
     const __m128i vq31prod1x02 = _mm_srli_epi64(_mm_add_epi64(vprod1x02, vrounding), 31);
     const __m128i vq31prod2x02 = _mm_srli_epi64(_mm_add_epi64(vprod2x02, vrounding), 31);
     const __m128i vq31prod3x02 = _mm_srli_epi64(_mm_add_epi64(vprod3x02, vrounding), 31);

     const __m128i vabsprod0x13 = _mm_mul_epu32(vabsacc0x1032, vmultiplier);
     const __m128i vabsprod1x13 = _mm_mul_epu32(vabsacc1x1032, vmultiplier);
     const __m128i vabsprod2x13 = _mm_mul_epu32(vabsacc2x1032, vmultiplier);
     const __m128i vabsprod3x13 = _mm_mul_epu32(vabsacc3x1032, vmultiplier);

     const __m128i vnmask0x13 = _mm_shuffle_epi32(vnmask0x0123, _MM_SHUFFLE(3, 3, 1, 1));
     const __m128i vnmask1x13 = _mm_shuffle_epi32(vnmask1x0123, _MM_SHUFFLE(3, 3, 1, 1));
     const __m128i vnmask2x13 = _mm_shuffle_epi32(vnmask2x0123, _MM_SHUFFLE(3, 3, 1, 1));
     const __m128i vnmask3x13 = _mm_shuffle_epi32(vnmask3x0123, _MM_SHUFFLE(3, 3, 1, 1));

     const __m128i vprod0x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod0x13, vnmask0x13), vnmask0x13);
     const __m128i vprod1x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod1x13, vnmask1x13), vnmask1x13);
     const __m128i vprod2x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod2x13, vnmask2x13), vnmask2x13);
     const __m128i vprod3x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod3x13, vnmask3x13), vnmask3x13);

     const __m128i vq31prod0x13 = _mm_srli_epi64(_mm_add_epi64(vprod0x13, vrounding), 31);
     const __m128i vq31prod1x13 = _mm_srli_epi64(_mm_add_epi64(vprod1x13, vrounding), 31);
     const __m128i vq31prod2x13 = _mm_srli_epi64(_mm_add_epi64(vprod2x13, vrounding), 31);
     const __m128i vq31prod3x13 = _mm_srli_epi64(_mm_add_epi64(vprod3x13, vrounding), 31);

     const __m128i vq31prod0x0213 = _mm_castps_si128(_mm_shuffle_ps(
         _mm_castsi128_ps(vq31prod0x02), _mm_castsi128_ps(vq31prod0x13), _MM_SHUFFLE(2, 0, 2, 0)));
     const __m128i vq31prod1x0213 = _mm_castps_si128(_mm_shuffle_ps(
         _mm_castsi128_ps(vq31prod1x02), _mm_castsi128_ps(vq31prod1x13), _MM_SHUFFLE(2, 0, 2, 0)));
     const __m128i vq31prod2x0213 = _mm_castps_si128(_mm_shuffle_ps(
         _mm_castsi128_ps(vq31prod2x02), _mm_castsi128_ps(vq31prod2x13), _MM_SHUFFLE(2, 0, 2, 0)));
     const __m128i vq31prod3x0213 = _mm_castps_si128(_mm_shuffle_ps(
         _mm_castsi128_ps(vq31prod3x02), _mm_castsi128_ps(vq31prod3x13), _MM_SHUFFLE(2, 0, 2, 0)));

     const __m128i vq31prod0x0123 = _mm_shuffle_epi32(vq31prod0x0213, _MM_SHUFFLE(3, 1, 2, 0));
     const __m128i vq31prod1x0123 = _mm_shuffle_epi32(vq31prod1x0213, _MM_SHUFFLE(3, 1, 2, 0));
     const __m128i vq31prod2x0123 = _mm_shuffle_epi32(vq31prod2x0213, _MM_SHUFFLE(3, 1, 2, 0));
     const __m128i vq31prod3x0123 = _mm_shuffle_epi32(vq31prod3x0213, _MM_SHUFFLE(3, 1, 2, 0));

     const __m128i vremainder_mask = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.remainder_mask);

     const __m128i vrem0x0123 =
       _mm_add_epi32(_mm_and_si128(vq31prod0x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod0x0123));
     const __m128i vrem1x0123 =
       _mm_add_epi32(_mm_and_si128(vq31prod1x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod1x0123));
     const __m128i vrem2x0123 =
       _mm_add_epi32(_mm_and_si128(vq31prod2x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod2x0123));
     const __m128i vrem3x0123 =
       _mm_add_epi32(_mm_and_si128(vq31prod3x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod3x0123));

     const __m128i vremainder_threshold = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.remainder_threshold);
     const __m128i vshift = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.shift);

     vacc0x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod0x0123, vshift), _mm_cmpgt_epi32(vrem0x0123, vremainder_threshold));
     vacc1x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod1x0123, vshift), _mm_cmpgt_epi32(vrem1x0123, vremainder_threshold));
     vacc2x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod2x0123, vshift), _mm_cmpgt_epi32(vrem2x0123, vremainder_threshold));
     vacc3x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod3x0123, vshift), _mm_cmpgt_epi32(vrem3x0123, vremainder_threshold));

     const __m128i voutput_zero_point = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_zero_point);
     const __m128i vacc01x0123 = _mm_adds_epi16(_mm_packs_epi32(vacc0x0123, vacc1x0123), voutput_zero_point);
     const __m128i vacc23x0123 = _mm_adds_epi16(_mm_packs_epi32(vacc2x0123, vacc3x0123), voutput_zero_point);
     __m128i vout = _mm_packus_epi16(vacc01x0123, vacc23x0123);
     vout = _mm_min_epu8(vout, _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_max));
     vout = _mm_max_epu8(vout, _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_min));

     if XNN_LIKELY(nc >= 4) {
       *((uint32_t*) c3) = (uint32_t) _mm_cvtsi128_si32(_mm_srli_si128(vout, 12));
       c3 += cn_stride;
       *((uint32_t*) c2) = (uint32_t) _mm_cvtsi128_si32(_mm_unpackhi_epi32(vout, vout));
       c2 += cn_stride;
       *((uint32_t*) c1) = (uint32_t) _mm_cvtsi128_si32(_mm_srli_epi64(vout, 32));
       c1 += cn_stride;
       *((uint32_t*) c0) = (uint32_t) _mm_cvtsi128_si32(vout);
       c0 += cn_stride;

       a = (const uint8_t**restrict) ((uintptr_t) a - ks);

       nc -= 4;
     } else {
       if (nc & 2) {
         *((uint16_t*) c3) = (uint16_t) _mm_extract_epi16(vout, 6); c3 += 2;
         *((uint16_t*) c2) = (uint16_t) _mm_extract_epi16(vout, 4); c2 += 2;
         *((uint16_t*) c1) = (uint16_t) _mm_extract_epi16(vout, 2); c1 += 2;
         *((uint16_t*) c0) = (uint16_t) _mm_extract_epi16(vout, 0); c0 += 2;
         vout = _mm_srli_epi32(vout, 16);
       }
       if (nc & 1) {
         *((uint8_t*) c3) = (uint8_t) _mm_extract_epi16(vout, 6);
         *((uint8_t*) c2) = (uint8_t) _mm_extract_epi16(vout, 4);
         *((uint8_t*) c1) = (uint8_t) _mm_extract_epi16(vout, 2);
         *((uint8_t*) c0) = (uint8_t) _mm_cvtsi128_si32(vout);
       }

       nc = 0;
     }
   } while (nc != 0);
 }
	// Copyright (c) Facebook, Inc. and its affiliates.
	// All rights reserved.
	//
	// Copyright 2019 Google LLC
	//
	// This source code is licensed under the BSD-style license found in the
	// LICENSE file in the root directory of this source tree.

	#include <assert.h>

	#include <immintrin.h>

	#include <xnnpack/igemm.h>
	#include <xnnpack/math.h>


	void xnn_qu8_igemm_minmax_gemmlowp_ukernel_4x4c2__sse2(
	size_t mr,
	size_t nc,
	size_t kc,
	size_t ks,
	const uint8_t** restrict a,
	const void* restrict w,
	uint8_t* restrict c,
	size_t cm_stride,
	size_t cn_stride,
	size_t a_offset,
	const uint8_t* zero,
	const union xnn_qu8_conv_minmax_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_DISABLE_TSAN
	{
	assert(mr != 0);
	assert(mr <= 4);
	assert(nc != 0);
	assert(kc != 0);
	assert(ks != 0);
	assert(ks % (4 * sizeof(void*)) == 0);
	assert(a_offset % sizeof(int8_t) == 0);
	assert(a != NULL);
	assert(w != NULL);
	assert(c != NULL);

	kc = round_up_po2(kc, 2);
	uint8_t* c0 = c;
	uint8_t* c1 = (uint8_t*) ((uintptr_t) c0 + cm_stride);
	if XNN_UNPREDICTABLE(mr < 2) {
	c1 = c0;
	}
	uint8_t* c2 = (uint8_t*) ((uintptr_t) c1 + cm_stride);
	if XNN_UNPREDICTABLE(mr <= 2) {
	c2 = c1;
	}
	uint8_t* c3 = (uint8_t*) ((uintptr_t) c2 + cm_stride);
	if (mr != 4) {
	c3 = c2;
	}

	const __m128i vb_zero_point = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.kernel_zero_point);

	do {
	__m128i vacc0x0123 = _mm_loadu_si128((const __m128i*) w);
	__m128i vacc1x0123 = vacc0x0123;
	__m128i vacc2x0123 = vacc0x0123;
	__m128i vacc3x0123 = vacc0x0123;
	w = (const void*) ((uintptr_t) w + 16);

	const __m128i vzero = _mm_setzero_si128();
	size_t p = ks;
	do {
	const uint8_t* restrict a0 = a[0];
	if XNN_UNPREDICTABLE(a0 != zero) {
	a0 = (const uint8_t*) ((uintptr_t) a0 + a_offset);
	}
	const uint8_t* restrict a1 = a[1];
	if XNN_UNPREDICTABLE(a1 != zero) {
	a1 = (const uint8_t*) ((uintptr_t) a1 + a_offset);
	}
	const uint8_t* restrict a2 = a[2];
	if XNN_UNPREDICTABLE(a2 != zero) {
	a2 = (const uint8_t*) ((uintptr_t) a2 + a_offset);
	}
	const uint8_t* restrict a3 = a[3];
	if XNN_UNPREDICTABLE(a3 != zero) {
	a3 = (const uint8_t*) ((uintptr_t) a3 + a_offset);
	}
	a += 4;

	size_t k = kc;
	while (k >= 8 * sizeof(uint8_t)) {
	const __m128i va0 = _mm_loadl_epi64((const __m128i*) a0);
	const __m128i vxa0 = _mm_unpacklo_epi8(va0, vzero);
	a0 += 8;
	const __m128i va1 = _mm_loadl_epi64((const __m128i*) a1);
	const __m128i vxa1 = _mm_unpacklo_epi8(va1, vzero);
	a1 += 8;
	const __m128i va2 = _mm_loadl_epi64((const __m128i*) a2);
	const __m128i vxa2 = _mm_unpacklo_epi8(va2, vzero);
	a2 += 8;
	const __m128i va3 = _mm_loadl_epi64((const __m128i*) a3);
	const __m128i vxa3 = _mm_unpacklo_epi8(va3, vzero);
	a3 += 8;

	const __m128i vb0 = _mm_loadl_epi64((const __m128i*) w);
	const __m128i vxb0 = _mm_sub_epi16(_mm_unpacklo_epi8(vb0, vzero), vb_zero_point);
	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));

	const __m128i vb1 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 8));
	const __m128i vxb1 = _mm_sub_epi16(_mm_unpacklo_epi8(vb1, vzero), vb_zero_point);
	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));

	const __m128i vb2 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 16));
	const __m128i vxb2 = _mm_sub_epi16(_mm_unpacklo_epi8(vb2, vzero), vb_zero_point);
	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));

	const __m128i vb3 = _mm_loadl_epi64((const __m128i*) ((uintptr_t) w + 24));
	const __m128i vxb3 = _mm_sub_epi16(_mm_unpacklo_epi8(vb3, vzero), vb_zero_point);
	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(3, 3, 3, 3)), vxb3));

	w = (void*) ((uintptr_t) w + 32);

	k -= 8 * sizeof(uint8_t);
	}
	if (k != 0) {
	const __m128i va0 = _mm_loadl_epi64((const __m128i*) a0);
	const __m128i vxa0 = _mm_unpacklo_epi8(va0, vzero);
	const __m128i va1 = _mm_loadl_epi64((const __m128i*) a1);
	const __m128i vxa1 = _mm_unpacklo_epi8(va1, vzero);
	const __m128i va2 = _mm_loadl_epi64((const __m128i*) a2);
	const __m128i vxa2 = _mm_unpacklo_epi8(va2, vzero);
	const __m128i va3 = _mm_loadl_epi64((const __m128i*) a3);
	const __m128i vxa3 = _mm_unpacklo_epi8(va3, vzero);

	const __m128i vb0 = _mm_loadl_epi64((const __m128i*) w);
	const __m128i vxb0 = _mm_sub_epi16(_mm_unpacklo_epi8(vb0, vzero), vb_zero_point);
	w = (void*) ((uintptr_t) w + 8);

	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(0, 0, 0, 0)), vxb0));

	if (k > 2 * sizeof(uint8_t)) {
	const __m128i vb1 = _mm_loadl_epi64((const __m128i*) w);
	const __m128i vxb1 = _mm_sub_epi16(_mm_unpacklo_epi8(vb1, vzero), vb_zero_point);
	w = (void*) ((uintptr_t) w + 8);

	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(1, 1, 1, 1)), vxb1));

	if (k > 4 * sizeof(uint8_t)) {
	const __m128i vb2 = _mm_loadl_epi64((const __m128i*) w);
	const __m128i vxb2 = _mm_sub_epi16(_mm_unpacklo_epi8(vb2, vzero), vb_zero_point);
	w = (void*) ((uintptr_t) w + 8);

	vacc0x0123 = _mm_add_epi32(vacc0x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa0, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc1x0123 = _mm_add_epi32(vacc1x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa1, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc2x0123 = _mm_add_epi32(vacc2x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa2, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	vacc3x0123 = _mm_add_epi32(vacc3x0123, _mm_madd_epi16(_mm_shuffle_epi32(vxa3, _MM_SHUFFLE(2, 2, 2, 2)), vxb2));
	}
	}
	}
	p -= 4 * sizeof(void*);
	} while (p != 0);

	const __m128i vmultiplier = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.multiplier);
	const __m128i vrounding = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.rounding);

	const __m128i vnmask0x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc0x0123);
	const __m128i vnmask1x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc1x0123);
	const __m128i vnmask2x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc2x0123);
	const __m128i vnmask3x0123 = _mm_cmpgt_epi32(_mm_setzero_si128(), vacc3x0123);

	const __m128i vabsacc0x0123 = _mm_sub_epi32(_mm_xor_si128(vacc0x0123, vnmask0x0123), vnmask0x0123);
	const __m128i vabsacc1x0123 = _mm_sub_epi32(_mm_xor_si128(vacc1x0123, vnmask1x0123), vnmask1x0123);
	const __m128i vabsacc2x0123 = _mm_sub_epi32(_mm_xor_si128(vacc2x0123, vnmask2x0123), vnmask2x0123);
	const __m128i vabsacc3x0123 = _mm_sub_epi32(_mm_xor_si128(vacc3x0123, vnmask3x0123), vnmask3x0123);

	const __m128i vabsacc0x1032 = _mm_shuffle_epi32(vabsacc0x0123, _MM_SHUFFLE(2, 3, 0, 1));
	const __m128i vabsacc1x1032 = _mm_shuffle_epi32(vabsacc1x0123, _MM_SHUFFLE(2, 3, 0, 1));
	const __m128i vabsacc2x1032 = _mm_shuffle_epi32(vabsacc2x0123, _MM_SHUFFLE(2, 3, 0, 1));
	const __m128i vabsacc3x1032 = _mm_shuffle_epi32(vabsacc3x0123, _MM_SHUFFLE(2, 3, 0, 1));

	const __m128i vabsprod0x02 = _mm_mul_epu32(vabsacc0x0123, vmultiplier);
	const __m128i vabsprod1x02 = _mm_mul_epu32(vabsacc1x0123, vmultiplier);
	const __m128i vabsprod2x02 = _mm_mul_epu32(vabsacc2x0123, vmultiplier);
	const __m128i vabsprod3x02 = _mm_mul_epu32(vabsacc3x0123, vmultiplier);

	const __m128i vnmask0x02 = _mm_shuffle_epi32(vnmask0x0123, _MM_SHUFFLE(2, 2, 0, 0));
	const __m128i vnmask1x02 = _mm_shuffle_epi32(vnmask1x0123, _MM_SHUFFLE(2, 2, 0, 0));
	const __m128i vnmask2x02 = _mm_shuffle_epi32(vnmask2x0123, _MM_SHUFFLE(2, 2, 0, 0));
	const __m128i vnmask3x02 = _mm_shuffle_epi32(vnmask3x0123, _MM_SHUFFLE(2, 2, 0, 0));

	const __m128i vprod0x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod0x02, vnmask0x02), vnmask0x02);
	const __m128i vprod1x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod1x02, vnmask1x02), vnmask1x02);
	const __m128i vprod2x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod2x02, vnmask2x02), vnmask2x02);
	const __m128i vprod3x02 = _mm_sub_epi64(_mm_xor_si128(vabsprod3x02, vnmask3x02), vnmask3x02);

	const __m128i vq31prod0x02 = _mm_srli_epi64(_mm_add_epi64(vprod0x02, vrounding), 31);
	const __m128i vq31prod1x02 = _mm_srli_epi64(_mm_add_epi64(vprod1x02, vrounding), 31);
	const __m128i vq31prod2x02 = _mm_srli_epi64(_mm_add_epi64(vprod2x02, vrounding), 31);
	const __m128i vq31prod3x02 = _mm_srli_epi64(_mm_add_epi64(vprod3x02, vrounding), 31);

	const __m128i vabsprod0x13 = _mm_mul_epu32(vabsacc0x1032, vmultiplier);
	const __m128i vabsprod1x13 = _mm_mul_epu32(vabsacc1x1032, vmultiplier);
	const __m128i vabsprod2x13 = _mm_mul_epu32(vabsacc2x1032, vmultiplier);
	const __m128i vabsprod3x13 = _mm_mul_epu32(vabsacc3x1032, vmultiplier);

	const __m128i vnmask0x13 = _mm_shuffle_epi32(vnmask0x0123, _MM_SHUFFLE(3, 3, 1, 1));
	const __m128i vnmask1x13 = _mm_shuffle_epi32(vnmask1x0123, _MM_SHUFFLE(3, 3, 1, 1));
	const __m128i vnmask2x13 = _mm_shuffle_epi32(vnmask2x0123, _MM_SHUFFLE(3, 3, 1, 1));
	const __m128i vnmask3x13 = _mm_shuffle_epi32(vnmask3x0123, _MM_SHUFFLE(3, 3, 1, 1));

	const __m128i vprod0x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod0x13, vnmask0x13), vnmask0x13);
	const __m128i vprod1x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod1x13, vnmask1x13), vnmask1x13);
	const __m128i vprod2x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod2x13, vnmask2x13), vnmask2x13);
	const __m128i vprod3x13 = _mm_sub_epi64(_mm_xor_si128(vabsprod3x13, vnmask3x13), vnmask3x13);

	const __m128i vq31prod0x13 = _mm_srli_epi64(_mm_add_epi64(vprod0x13, vrounding), 31);
	const __m128i vq31prod1x13 = _mm_srli_epi64(_mm_add_epi64(vprod1x13, vrounding), 31);
	const __m128i vq31prod2x13 = _mm_srli_epi64(_mm_add_epi64(vprod2x13, vrounding), 31);
	const __m128i vq31prod3x13 = _mm_srli_epi64(_mm_add_epi64(vprod3x13, vrounding), 31);

	const __m128i vq31prod0x0213 = _mm_castps_si128(_mm_shuffle_ps(
	_mm_castsi128_ps(vq31prod0x02), _mm_castsi128_ps(vq31prod0x13), _MM_SHUFFLE(2, 0, 2, 0)));
	const __m128i vq31prod1x0213 = _mm_castps_si128(_mm_shuffle_ps(
	_mm_castsi128_ps(vq31prod1x02), _mm_castsi128_ps(vq31prod1x13), _MM_SHUFFLE(2, 0, 2, 0)));
	const __m128i vq31prod2x0213 = _mm_castps_si128(_mm_shuffle_ps(
	_mm_castsi128_ps(vq31prod2x02), _mm_castsi128_ps(vq31prod2x13), _MM_SHUFFLE(2, 0, 2, 0)));
	const __m128i vq31prod3x0213 = _mm_castps_si128(_mm_shuffle_ps(
	_mm_castsi128_ps(vq31prod3x02), _mm_castsi128_ps(vq31prod3x13), _MM_SHUFFLE(2, 0, 2, 0)));

	const __m128i vq31prod0x0123 = _mm_shuffle_epi32(vq31prod0x0213, _MM_SHUFFLE(3, 1, 2, 0));
	const __m128i vq31prod1x0123 = _mm_shuffle_epi32(vq31prod1x0213, _MM_SHUFFLE(3, 1, 2, 0));
	const __m128i vq31prod2x0123 = _mm_shuffle_epi32(vq31prod2x0213, _MM_SHUFFLE(3, 1, 2, 0));
	const __m128i vq31prod3x0123 = _mm_shuffle_epi32(vq31prod3x0213, _MM_SHUFFLE(3, 1, 2, 0));

	const __m128i vremainder_mask = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.remainder_mask);

	const __m128i vrem0x0123 =
	_mm_add_epi32(_mm_and_si128(vq31prod0x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod0x0123));
	const __m128i vrem1x0123 =
	_mm_add_epi32(_mm_and_si128(vq31prod1x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod1x0123));
	const __m128i vrem2x0123 =
	_mm_add_epi32(_mm_and_si128(vq31prod2x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod2x0123));
	const __m128i vrem3x0123 =
	_mm_add_epi32(_mm_and_si128(vq31prod3x0123, vremainder_mask), _mm_cmpgt_epi32(_mm_setzero_si128(), vq31prod3x0123));

	const __m128i vremainder_threshold = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.remainder_threshold);
	const __m128i vshift = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.shift);

	vacc0x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod0x0123, vshift), _mm_cmpgt_epi32(vrem0x0123, vremainder_threshold));
	vacc1x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod1x0123, vshift), _mm_cmpgt_epi32(vrem1x0123, vremainder_threshold));
	vacc2x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod2x0123, vshift), _mm_cmpgt_epi32(vrem2x0123, vremainder_threshold));
	vacc3x0123 = _mm_sub_epi32(_mm_sra_epi32(vq31prod3x0123, vshift), _mm_cmpgt_epi32(vrem3x0123, vremainder_threshold));

	const __m128i voutput_zero_point = _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_zero_point);
	const __m128i vacc01x0123 = _mm_adds_epi16(_mm_packs_epi32(vacc0x0123, vacc1x0123), voutput_zero_point);
	const __m128i vacc23x0123 = _mm_adds_epi16(_mm_packs_epi32(vacc2x0123, vacc3x0123), voutput_zero_point);
	__m128i vout = _mm_packus_epi16(vacc01x0123, vacc23x0123);
	vout = _mm_min_epu8(vout, _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_max));
	vout = _mm_max_epu8(vout, _mm_load_si128((const __m128i*) params->gemmlowp_sse2.output_min));

	if XNN_LIKELY(nc >= 4) {
	((uint32_t) c3) = (uint32_t) _mm_cvtsi128_si32(_mm_srli_si128(vout, 12));
	c3 += cn_stride;
	((uint32_t) c2) = (uint32_t) _mm_cvtsi128_si32(_mm_unpackhi_epi32(vout, vout));
	c2 += cn_stride;
	((uint32_t) c1) = (uint32_t) _mm_cvtsi128_si32(_mm_srli_epi64(vout, 32));
	c1 += cn_stride;
	((uint32_t) c0) = (uint32_t) _mm_cvtsi128_si32(vout);
	c0 += cn_stride;

	a = (const uint8_t**restrict) ((uintptr_t) a - ks);

	nc -= 4;
	} else {
	if (nc & 2) {
	((uint16_t) c3) = (uint16_t) _mm_extract_epi16(vout, 6); c3 += 2;
	((uint16_t) c2) = (uint16_t) _mm_extract_epi16(vout, 4); c2 += 2;
	((uint16_t) c1) = (uint16_t) _mm_extract_epi16(vout, 2); c1 += 2;
	((uint16_t) c0) = (uint16_t) _mm_extract_epi16(vout, 0); c0 += 2;
	vout = _mm_srli_epi32(vout, 16);
	}
	if (nc & 1) {
	((uint8_t) c3) = (uint8_t) _mm_extract_epi16(vout, 6);
	((uint8_t) c2) = (uint8_t) _mm_extract_epi16(vout, 4);
	((uint8_t) c1) = (uint8_t) _mm_extract_epi16(vout, 2);
	((uint8_t) c0) = (uint8_t) _mm_cvtsi128_si32(vout);
	}

	nc = 0;
	}
	} while (nc != 0);
	}