include/gmx_avx_single.h

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  35 #ifndef _gmx_avx_single_h_
  36 #define _gmx_avx_single_h_
  37
  38 /* We require AVX now! */
  39
  40 #include <immintrin.h> /* AVX */
  41
  42 static inline __m256
  43 gmx_mm256_invsqrt_ps(__m256 x)
  44 {
  45     const __m256 half  = _mm256_set_ps(0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5);
  46     const __m256 three = _mm256_set_ps(3.0, 3.0, 3.0, 3.0, 3.0, 3.0, 3.0, 3.0);
  47
  48     __m256       lu = _mm256_rsqrt_ps(x);
  49
  50     return _mm256_mul_ps(half, _mm256_mul_ps(_mm256_sub_ps(three, _mm256_mul_ps(_mm256_mul_ps(lu, lu), x)), lu));
  51 }
  52
  53 static inline __m256
  54 gmx_mm256_calc_rsq_ps(__m256 dx, __m256 dy, __m256 dz)
  55 {
  56     return _mm256_add_ps( _mm256_add_ps( _mm256_mul_ps(dx, dx), _mm256_mul_ps(dy, dy) ), _mm256_mul_ps(dz, dz) );
  57 }
  58
  59 /* Normal sum of four xmm registers */
  60 #define gmx_mm256_sum4_ps(t0, t1, t2, t3)  _mm256_add_ps(_mm256_add_ps(t0, t1), _mm256_add_ps(t2, t3))
  61
  62 #endif /* gmx_avx_single_h_ */