include/gmx_avx_single.h

   1 /*
   2  *                This source code is part of
   3  *
   4  *                 G   R   O   M   A   C   S
   5  *
   6  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
   7  * Copyright (c) 2001-2012, The GROMACS Development Team
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  10  * written by Erik Lindahl, David van der Spoel, Berk Hess, and others - for
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  12  *
  13  * This program is free software; you can redistribute it and/or modify it under
  14  * the terms of the GNU Lesser General Public License as published by the Free
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  16  * later version.
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  18  * library without restriction.  Specifically, if other files instantiate
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  22  * the GNU Lesser General Public License.
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  29  */
  30 #ifndef _gmx_avx_single_h_
  31 #define _gmx_avx_single_h_
  32
  33 /* We require AVX now! */
  34
  35 #include <immintrin.h> /* AVX */
  36
  37 static inline __m256
  38 gmx_mm256_invsqrt_ps(__m256 x)
  39 {
  40     const __m256 half  = _mm256_set_ps(0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5);
  41     const __m256 three = _mm256_set_ps(3.0,3.0,3.0,3.0,3.0,3.0,3.0,3.0);
  42
  43     __m256 lu = _mm256_rsqrt_ps(x);
  44
  45     return _mm256_mul_ps(half,_mm256_mul_ps(_mm256_sub_ps(three,_mm256_mul_ps(_mm256_mul_ps(lu,lu),x)),lu));
  46 }
  47
  48 static inline __m256
  49 gmx_mm256_calc_rsq_ps(__m256 dx, __m256 dy, __m256 dz)
  50 {
  51     return _mm256_add_ps( _mm256_add_ps( _mm256_mul_ps(dx,dx), _mm256_mul_ps(dy,dy) ), _mm256_mul_ps(dz,dz) );
  52 }
  53
  54 /* Normal sum of four xmm registers */
  55 #define gmx_mm256_sum4_ps(t0,t1,t2,t3)  _mm256_add_ps(_mm256_add_ps(t0,t1),_mm256_add_ps(t2,t3))
  56
  57 #endif /* gmx_avx_single_h_ */