src/gromacs/simd/vector_operations.h

   1 /*
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   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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  35
  36 /*! \libinternal \file
  37  *
  38  * \brief SIMD operations corresponding to Gromacs rvec datatypes.
  39  *
  40  * \author Erik Lindahl <erik.lindahl@scilifelab.se>
  41  *
  42  * \inlibraryapi
  43  * \ingroup module_simd
  44  */
  45
  46 #ifndef GMX_SIMD_VECTOR_OPERATIONS_H
  47 #define GMX_SIMD_VECTOR_OPERATIONS_H
  48
  49 #include "config.h"
  50
  51 #include "gromacs/simd/simd.h"
  52
  53 namespace gmx
  54 {
  55
  56 #if GMX_SIMD
  57
  58 /*! \cond libapi */
  59 /*! \addtogroup module_simd */
  60 /*! \{ */
  61
  62 /* This check is not actually required, but it must be true if the
  63  * code below actualy declares anything, and it makes it easy for
  64  * check-source to know that this file depends on simd.h (though
  65  * symbols like GMX_SIMD_HAVE_FLOAT are actually defined in its
  66  * implementation headers). */
  67 #if GMX_SIMD_HAVE_REAL || defined DOXYGEN
  68
  69 #if GMX_SIMD_HAVE_FLOAT || defined DOXYGEN
  70 /*! \brief SIMD float inner product of multiple float vectors.
  71  *
  72  * \param ax X components of first vectors
  73  * \param ay Y components of first vectors
  74  * \param az Z components of first vectors
  75  * \param bx X components of second vectors
  76  * \param by Y components of second vectors
  77  * \param bz Z components of second vectors
  78  *
  79  * \return Element i will be res[i] = ax[i]*bx[i]+ay[i]*by[i]+az[i]*bz[i].
  80  *
  81  * \note The SIMD part is that we calculate many scalar products in one call.
  82  */
  83 static inline SimdFloat gmx_simdcall
  84 iprod(SimdFloat ax, SimdFloat ay, SimdFloat az,
  85       SimdFloat bx, SimdFloat by, SimdFloat bz)
  86 {
  87     SimdFloat ret;
  88
  89     ret = ax * bx;
  90     ret = ay * by + ret;
  91     ret = az * bz + ret;
  92
  93     return ret;
  94 }
  95
  96 /*! \brief SIMD float norm squared of multiple vectors.
  97  *
  98  * \param ax X components of vectors
  99  * \param ay Y components of vectors
 100  * \param az Z components of vectors
 101  *
 102  * \return Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
 103  *
 104  * \note This corresponds to the scalar product of the vector with itself, but
 105  * the compiler might be able to optimize it better with identical vectors.
 106  */
 107 static inline SimdFloat gmx_simdcall
 108 norm2(SimdFloat ax, SimdFloat ay, SimdFloat az)
 109 {
 110     SimdFloat ret;
 111
 112     ret = ax * ax;
 113     ret = ay * ay + ret;
 114     ret = az * az + ret;
 115
 116     return ret;
 117 }
 118
 119 /*! \brief SIMD float cross-product of multiple vectors.
 120  *
 121  * \param ax X components of first vectors
 122  * \param ay Y components of first vectors
 123  * \param az Z components of first vectors
 124  * \param bx X components of second vectors
 125  * \param by Y components of second vectors
 126  * \param bz Z components of second vectors
 127  * \param[out] cx X components of cross product vectors
 128  * \param[out] cy Y components of cross product vectors
 129  * \param[out] cz Z components of cross product vectors
 130  *
 131  * \returns void
 132  *
 133  * This calculates C = A x B, where the cross denotes the cross product.
 134  * The arguments x/y/z denotes the different components, and each element
 135  * corresponds to a separate vector.
 136  */
 137 static inline void gmx_simdcall
 138 cprod(SimdFloat ax, SimdFloat ay, SimdFloat az,
 139       SimdFloat bx, SimdFloat by, SimdFloat bz,
 140       SimdFloat *cx, SimdFloat *cy, SimdFloat *cz)
 141 {
 142     *cx = ay * bz;
 143     *cx = fnma(az, by, *cx);
 144
 145     *cy = az * bx;
 146     *cy = fnma(ax, bz, *cy);
 147
 148     *cz = ax * by;
 149     *cz = fnma(ay, bx, *cz);
 150 }
 151 #endif // GMX_SIMD_HAVE_FLOAT
 152
 153 #if GMX_SIMD_HAVE_DOUBLE || defined DOXYGEN
 154 /*! \brief SIMD double inner product of multiple double vectors.
 155  *
 156  * \param ax X components of first vectors
 157  * \param ay Y components of first vectors
 158  * \param az Z components of first vectors
 159  * \param bx X components of second vectors
 160  * \param by Y components of second vectors
 161  * \param bz Z components of second vectors
 162  *
 163  * \return Element i will be res[i] = ax[i]*bx[i]+ay[i]*by[i]+az[i]*bz[i].
 164  *
 165  * \note The SIMD part is that we calculate many scalar products in one call.
 166  */
 167 static inline SimdDouble gmx_simdcall
 168 iprod(SimdDouble ax, SimdDouble ay, SimdDouble az,
 169       SimdDouble bx, SimdDouble by, SimdDouble bz)
 170 {
 171     SimdDouble ret;
 172
 173     ret = ax * bx;
 174     ret = ay * by + ret;
 175     ret = az * bz + ret;
 176
 177     return ret;
 178 }
 179
 180 /*! \brief SIMD double norm squared of multiple vectors.
 181  *
 182  * \param ax X components of vectors
 183  * \param ay Y components of vectors
 184  * \param az Z components of vectors
 185  *
 186  * \return Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
 187  *
 188  * \note This corresponds to the scalar product of the vector with itself, but
 189  * the compiler might be able to optimize it better with identical vectors.
 190  */
 191 static inline SimdDouble gmx_simdcall
 192 norm2(SimdDouble ax, SimdDouble ay, SimdDouble az)
 193 {
 194     SimdDouble ret;
 195
 196     ret = ax * ax;
 197     ret = ay * ay + ret;
 198     ret = az * az + ret;
 199
 200     return ret;
 201 }
 202
 203 /*! \brief SIMD double cross-product of multiple vectors.
 204  *
 205  * \param ax X components of first vectors
 206  * \param ay Y components of first vectors
 207  * \param az Z components of first vectors
 208  * \param bx X components of second vectors
 209  * \param by Y components of second vectors
 210  * \param bz Z components of second vectors
 211  * \param[out] cx X components of cross product vectors
 212  * \param[out] cy Y components of cross product vectors
 213  * \param[out] cz Z components of cross product vectors
 214  *
 215  * \returns void
 216  *
 217  * This calculates C = A x B, where the cross denotes the cross product.
 218  * The arguments x/y/z denotes the different components, and each element
 219  * corresponds to a separate vector.
 220  */
 221 static inline void gmx_simdcall
 222 cprod(SimdDouble ax, SimdDouble ay, SimdDouble az,
 223       SimdDouble bx, SimdDouble by, SimdDouble bz,
 224       SimdDouble *cx, SimdDouble *cy, SimdDouble *cz)
 225 {
 226     *cx = ay * bz;
 227     *cx = *cx - az * by;
 228
 229     *cy = az * bx;
 230     *cy = *cy - ax * bz;
 231
 232     *cz = ax * by;
 233     *cz = *cz - ay * bx;
 234 }
 235 #endif // GMX_SIMD_HAVE_DOUBLE
 236
 237
 238 #if GMX_SIMD4_HAVE_FLOAT || defined DOXYGEN
 239 /*! \brief SIMD4 float norm squared of multiple vectors.
 240  *
 241  * \param ax X components of vectors
 242  * \param ay Y components of vectors
 243  * \param az Z components of vectors
 244  *
 245  * \return Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
 246  *
 247  * \note This corresponds to the scalar product of the vector with itself, but
 248  * the compiler might be able to optimize it better with identical vectors.
 249  */
 250 static inline Simd4Float gmx_simdcall
 251 norm2(Simd4Float ax, Simd4Float ay, Simd4Float az)
 252 {
 253     Simd4Float ret;
 254
 255     ret = ax * ax;
 256     ret = ay * ay + ret;
 257     ret = az * az + ret;
 258
 259     return ret;
 260 }
 261
 262 #endif // GMX_SIMD4_HAVE_FLOAT
 263
 264 #if GMX_SIMD4_HAVE_DOUBLE || defined DOXYGEN
 265 /*! \brief SIMD4 double norm squared of multiple vectors.
 266  *
 267  * \param ax X components of vectors
 268  * \param ay Y components of vectors
 269  * \param az Z components of vectors
 270  *
 271  * \return Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
 272  *
 273  * \note This corresponds to the scalar product of the vector with itself, but
 274  * the compiler might be able to optimize it better with identical vectors.
 275  */
 276 static inline Simd4Double gmx_simdcall
 277 norm2(Simd4Double ax, Simd4Double ay, Simd4Double az)
 278 {
 279     Simd4Double ret;
 280
 281     ret = ax * ax;
 282     ret = ay * ay + ret;
 283     ret = az * az + ret;
 284
 285     return ret;
 286 }
 287
 288 #endif // GMX_SIMD4_HAVE_DOUBLE
 289
 290 #endif // GMX_SIMD_HAVE REAL || defined DOXYGEN
 291
 292 /*! \} */
 293 /*! \endcond */
 294
 295 #endif // GMX_SIMD
 296
 297 }      // namespace gmx
 298
 299 #endif // GMX_SIMD_VECTOR_OPERATIONS_H