src/gromacs/simd/impl_reference/impl_reference_definitions.h

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  35
  36 #ifndef GMX_SIMD_IMPL_REFERENCE_DEFINITIONS_H
  37 #define GMX_SIMD_IMPL_REFERENCE_DEFINITIONS_H
  38
  39 /*! \libinternal \file
  40  *
  41  * \brief Reference SIMD implementation, including SIMD documentation.
  42  *
  43  * \author Erik Lindahl <erik.lindahl@scilifelab.se>
  44  *
  45  * \ingroup module_simd
  46  */
  47 namespace gmx
  48 {
  49
  50 /*! \cond libapi */
  51 /*! \ingroup module_simd */
  52 /*! \{ */
  53
  54 /*! \name SIMD implementation capability definitions
  55  *  \{
  56  */
  57
  58 /* We list all the capability definitions in the main/wrapper SIMD header for
  59  * each implementation, so we don't forget to set values for unsupported
  60  * features to 0.
  61  */
  62
  63 //! \brief 1 if any SIMD support is present, otherwise 0.
  64 #define GMX_SIMD 1
  65
  66 /*! \brief 1 when SIMD float support is present, otherwise 0
  67  *
  68  * You should only use this to specifically check for single precision SIMD,
  69  * support, even when the rest of Gromacs uses double precision.
  70  */
  71 #define GMX_SIMD_HAVE_FLOAT 1
  72
  73 //! \brief 1 if SIMD double support is present, otherwise 0
  74 #define GMX_SIMD_HAVE_DOUBLE 1
  75
  76 //! \brief 1 if the SIMD implementation supports unaligned loads, otherwise 0
  77 #define GMX_SIMD_HAVE_LOADU 1
  78
  79 //! \brief 1 if the SIMD implementation supports unaligned stores, otherwise 0
  80 #define GMX_SIMD_HAVE_STOREU 1
  81
  82 /*! \brief 1 if the SIMD implementation has fused-multiply add hardware
  83  *
  84  * \note All the fused multiply-add functions are always available and can be
  85  *       used in any code (by executing separate multiply and add ops), but in
  86  *       a few very tight loops you might be able to save a few instructions
  87  *       with a separate non-FMA code path.
  88  */
  89 #define GMX_SIMD_HAVE_FMA 0
  90
  91 //! \brief 1 if SIMD impl has logical operations on floating-point data, otherwise 0
  92 #define GMX_SIMD_HAVE_LOGICAL 1
  93
  94 //! \brief Support for extracting integers from \ref gmx::SimdFInt32 (1/0 for present/absent)
  95 #define GMX_SIMD_HAVE_FINT32_EXTRACT 1
  96
  97 //! \brief 1 if SIMD logical ops are supported for \ref gmx::SimdFInt32, otherwise 0
  98 #define GMX_SIMD_HAVE_FINT32_LOGICAL 1
  99
 100 //! \brief 1 if SIMD arithmetic ops are supported for \ref gmx::SimdFInt32, otherwise 0
 101 #define GMX_SIMD_HAVE_FINT32_ARITHMETICS 1
 102
 103 //! \brief Support for extracting integer from \ref gmx::SimdDInt32 (1/0 for present/absent)
 104 #define GMX_SIMD_HAVE_DINT32_EXTRACT 1
 105
 106 //! \brief 1 if logical operations are supported for \ref gmx::SimdDInt32, otherwise 0
 107 #define GMX_SIMD_HAVE_DINT32_LOGICAL 1
 108
 109 //! \brief 1 if SIMD arithmetic ops are supported for \ref gmx::SimdDInt32, otherwise 0
 110 #define GMX_SIMD_HAVE_DINT32_ARITHMETICS 1
 111
 112 /*! \brief 1 if implementation provides single precision copysign()
 113  *
 114  *  Only used in simd_math.h to selectively override the generic implementation.
 115  */
 116 #define GMX_SIMD_HAVE_NATIVE_COPYSIGN_FLOAT 0
 117
 118 /*! \brief 1 if implementation provides single precision 1/sqrt(x) N-R iterations faster than simd_math.h
 119  *
 120  *  Only used in simd_math.h to selectively override the generic implementation.
 121  */
 122 #define GMX_SIMD_HAVE_NATIVE_RSQRT_ITER_FLOAT 0
 123
 124 /*! \brief 1 if implementation provides single precision 1/x N-R iterations faster than simd_math.h
 125  *
 126  *  Only used in simd_math.h to selectively override the generic implementation.
 127  */
 128 #define GMX_SIMD_HAVE_NATIVE_RCP_ITER_FLOAT 0
 129
 130 /*! \brief 1 if implementation provides single precision log() faster than simd_math.h
 131  *
 132  *  Only used in simd_math.h to selectively override the generic implementation.
 133  */
 134 #define GMX_SIMD_HAVE_NATIVE_LOG_FLOAT 0
 135
 136 /*! \brief 1 if implementation provides single precision exp2() faster than simd_math.h
 137  *
 138  *  Only used in simd_math.h to selectively override the generic implementation.
 139  */
 140 #define GMX_SIMD_HAVE_NATIVE_EXP2_FLOAT 0
 141
 142 /*! \brief 1 if implementation provides single precision exp() faster than simd_math.h
 143  *
 144  *  Only used in simd_math.h to selectively override the generic implementation.
 145  */
 146 #define GMX_SIMD_HAVE_NATIVE_EXP_FLOAT 0
 147
 148 /*! \brief 1 if implementation provides double precision copysign()
 149  *
 150  *  Only used in simd_math.h to selectively override the generic implementation.
 151  */
 152 #define GMX_SIMD_HAVE_NATIVE_COPYSIGN_DOUBLE 0
 153
 154 /*! \brief 1 if implementation provides double precision 1/sqrt(x) N-R iterations faster than simd_math.h
 155  *
 156  *  Only used in simd_math.h to selectively override the generic implementation.
 157  */
 158 #define GMX_SIMD_HAVE_NATIVE_RSQRT_ITER_DOUBLE 0
 159
 160 /*! \brief 1 if implementation provides double precision 1/x N-R iterations faster than simd_math.h
 161  *
 162  *  Only used in simd_math.h to selectively override the generic implementation.
 163  */
 164 #define GMX_SIMD_HAVE_NATIVE_RCP_ITER_DOUBLE 0
 165
 166 /*! \brief 1 if implementation provides double precision log() faster than simd_math.h
 167  *
 168  *  Only used in simd_math.h to selectively override the generic implementation.
 169  */
 170 #define GMX_SIMD_HAVE_NATIVE_LOG_DOUBLE 0
 171
 172 /*! \brief 1 if implementation provides double precision exp2() faster than simd_math.h
 173  *
 174  *  Only used in simd_math.h to selectively override the generic implementation.
 175  */
 176 #define GMX_SIMD_HAVE_NATIVE_EXP2_DOUBLE 0
 177
 178 /*! \brief 1 if implementation provides double precision exp() faster than simd_math.h
 179  *
 180  *  Only used in simd_math.h to selectively override the generic implementation.
 181  */
 182 #define GMX_SIMD_HAVE_NATIVE_EXP_DOUBLE 0
 183
 184 //! \brief 1 if \ref gmx::gatherLoadUBySimdIntTranspose is present, otherwise 0
 185 #define GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_FLOAT 1
 186
 187 //! \brief 1 if \ref gmx::gatherLoadUBySimdIntTranspose is present, otherwise 0
 188 #define GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_DOUBLE 1
 189
 190 //! \brief 1 if float half-register load/store/reduce utils present, otherwise 0
 191 #define GMX_SIMD_HAVE_HSIMD_UTIL_FLOAT 1
 192
 193 //! \brief 1 if double half-register load/store/reduce utils present, otherwise 0
 194 #define GMX_SIMD_HAVE_HSIMD_UTIL_DOUBLE 1
 195
 196 #ifdef GMX_SIMD_REF_FLOAT_WIDTH
 197 #    define GMX_SIMD_FLOAT_WIDTH GMX_SIMD_REF_FLOAT_WIDTH
 198 #else
 199 //! \brief Width of the \ref gmx::SimdFloat datatype
 200 #    define GMX_SIMD_FLOAT_WIDTH 4
 201 #endif
 202
 203 #ifdef GMX_SIMD_REF_DOUBLE_WIDTH
 204 #    define GMX_SIMD_DOUBLE_WIDTH GMX_SIMD_REF_DOUBLE_WIDTH
 205 #else
 206 //! \brief Width of the \ref gmx::SimdDouble datatype
 207 #    define GMX_SIMD_DOUBLE_WIDTH 4
 208 #endif
 209
 210 #if GMX_SIMD_FLOAT_WIDTH >= 8 || defined DOXYGEN // set in simd.h for GMX_SIMD_FLOAT_WIDTH<=4
 211 //! \brief 1 if float 4xN load utils present, otherwise 0
 212 #    define GMX_SIMD_HAVE_4NSIMD_UTIL_FLOAT 1
 213 #endif
 214
 215 #if GMX_SIMD_DOUBLE_WIDTH >= 8 || defined DOXYGEN // set in simd.h for GMX_SIMD_DOUBLE_WIDTH<=4
 216 //! \brief 1 if double 4xN load utils present, otherwise 0
 217 #    define GMX_SIMD_HAVE_4NSIMD_UTIL_DOUBLE 1
 218 #endif
 219
 220 //! \brief 1 if implementation provides \ref gmx::Simd4Float, otherwise 0.
 221 #define GMX_SIMD4_HAVE_FLOAT 1
 222
 223 //! \brief 1 if the implementation provides \ref gmx::Simd4Double, otherwise 0.
 224 #define GMX_SIMD4_HAVE_DOUBLE 1
 225
 226 //! \brief Width of the \ref gmx::SimdFInt32 datatype.
 227 #define GMX_SIMD_FINT32_WIDTH GMX_SIMD_FLOAT_WIDTH
 228
 229 //! \brief Width of the \ref gmx::SimdDInt32 datatype.
 230 #define GMX_SIMD_DINT32_WIDTH GMX_SIMD_DOUBLE_WIDTH
 231
 232 //! \brief The SIMD4 type is always four units wide, but this makes code more explicit
 233 #define GMX_SIMD4_WIDTH 4
 234
 235 /*! \brief Maximum required alignment in bytes for aligned load/store of multiple
 236  * values (maximum required for either float or double). */
 237 #if GMX_SIMD_DOUBLE_WIDTH >= 2 * GMX_SIMD_FLOAT_WIDTH
 238 #    define GMX_SIMD_ALIGNMENT (GMX_SIMD_DOUBLE_WIDTH * 8)
 239 #else
 240 #    define GMX_SIMD_ALIGNMENT (GMX_SIMD_FLOAT_WIDTH * 4)
 241 #endif
 242
 243 //! \brief Accuracy of SIMD 1/sqrt(x) lookup. Used to determine number of iterations.
 244 #define GMX_SIMD_RSQRT_BITS 23
 245
 246 //! \brief Accuracy of SIMD 1/x lookup. Used to determine number of iterations.
 247 #define GMX_SIMD_RCP_BITS 23
 248
 249 //! \}
 250
 251 //! \}
 252
 253 //! \endcond
 254
 255 } // namespace gmx
 256 #endif // GMX_SIMD_IMPL_REFERENCE_DEFINITIONS_H