text: #include "crypto_decode_761x3.h"
  #include <immintrin.h>
  #define uint8 uint8_t
  
  #define p 761
  #define loops 6
  #define overshoot 2
  
  void PQCLEAN_NTRULPR761_AVX2_crypto_decode_761x3(void *v, const unsigned char *s) {
      uint8 *f = v;
      int loop;
      uint8 *nextf = f + 128 - 4 * overshoot;
      const unsigned char *nexts = s + 32 - overshoot;
  
      for (loop = loops; loop > 0; --loop) {
          __m256i s0 = _mm256_loadu_si256((const __m256i *) s);
          s = nexts;
          nexts += 32;
  
          __m256i s1 = _mm256_srli_epi16(s0 & _mm256_set1_epi8(-16), 4);
          s0 &= _mm256_set1_epi8(15);
  
          __m256i a0 = _mm256_unpacklo_epi8(s0, s1);
          /* 0 0>>4 1 1>>4 2 2>>4 3 3>>4 4 4>>4 5 5>>4 6 6>>4 7 7>>4 */
          /* 16 16>>4 ... */
          __m256i a1 = _mm256_unpackhi_epi8(s0, s1);
          /* 8 8>>4 9 9>>4 10 10>>4 ... */
          /* 24 24>>4 ... */
  
          __m256i a2 = _mm256_srli_epi16(a0 & _mm256_set1_epi8(12), 2);
          __m256i a3 = _mm256_srli_epi16(a1 & _mm256_set1_epi8(12), 2);
          a0 &= _mm256_set1_epi8(3);
          a1 &= _mm256_set1_epi8(3);
  
          __m256i b0 = _mm256_unpacklo_epi8(a0, a2);
          /* 0 0>>2 0>>4 0>>6 1 1>>2 1>>4 1>>6 */
          /* 2 2>>2 2>>4 2>>6 3 3>>2 3>>4 3>.6 */
          /* 16 16>>2 16>>4 16>>6 ... */
          __m256i b2 = _mm256_unpackhi_epi8(a0, a2);
          /* 4 4>>2 ... */
          __m256i b1 = _mm256_unpacklo_epi8(a1, a3);
          /* 8 8>>2 ... */
          __m256i b3 = _mm256_unpackhi_epi8(a1, a3);
          /* 12 12>>2 ... */
  
          __m256i f0 = _mm256_permute2x128_si256(b0, b2, 0x20);
          __m256i f2 = _mm256_permute2x128_si256(b0, b2, 0x31);
          __m256i f1 = _mm256_permute2x128_si256(b1, b3, 0x20);
          __m256i f3 = _mm256_permute2x128_si256(b1, b3, 0x31);
  
          f0 = _mm256_add_epi8(f0, _mm256_set1_epi8(-1));
          f1 = _mm256_add_epi8(f1, _mm256_set1_epi8(-1));
          f2 = _mm256_add_epi8(f2, _mm256_set1_epi8(-1));
          f3 = _mm256_add_epi8(f3, _mm256_set1_epi8(-1));
  
          _mm256_storeu_si256((__m256i *) (f + 0), f0);
          _mm256_storeu_si256((__m256i *) (f + 32), f1);
          _mm256_storeu_si256((__m256i *) (f + 64), f2);
          _mm256_storeu_si256((__m256i *) (f + 96), f3);
          f = nextf;
          nextf += 128;
      }
  
      *f = (uint8) ((*s & 3) - 1);
  }
  