src/gromacs/ewald/pme-simd.h

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  35 #ifndef GMX_EWALD_PME_SIMD_H
  36 #define GMX_EWALD_PME_SIMD_H
  37
  38 /* Include the SIMD macro file and then check for support */
  39 #include "gromacs/simd/simd.h"
  40
  41 /* Check if we have 4-wide SIMD macro support */
  42 #if GMX_SIMD4_HAVE_REAL
  43 /* Do PME spread and gather with 4-wide SIMD.
  44  * NOTE: SIMD is only used with PME order 4 and 5 (which are the most common).
  45  */
  46 #    define PME_SIMD4_SPREAD_GATHER
  47
  48 #    if GMX_SIMD_HAVE_LOADU && GMX_SIMD_HAVE_STOREU
  49 /* With PME-order=4 on x86, unaligned load+store is slightly faster
  50  * than doubling all SIMD operations when using aligned load+store.
  51  */
  52 #        define PME_SIMD4_UNALIGNED
  53 #    endif
  54 #endif
  55
  56 #ifdef PME_SIMD4_SPREAD_GATHER
  57 #    define SIMD4_ALIGNMENT  (GMX_SIMD4_WIDTH*sizeof(real))
  58 #else
  59 /* We can use any alignment, apart from 0, so we use 4 reals */
  60 #    define SIMD4_ALIGNMENT  (4*sizeof(real))
  61 #endif
  62
  63 #endif