src/gromacs/simd/impl_x86_avx2_256/impl_x86_avx2_256_simd_double.h

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  35
  36 #ifndef GMX_SIMD_IMPL_X86_AVX2_256_SIMD_DOUBLE_H
  37 #define GMX_SIMD_IMPL_X86_AVX2_256_SIMD_DOUBLE_H
  38
  39 #include "config.h"
  40
  41 #include <immintrin.h>
  42
  43 #include "gromacs/math/utilities.h"
  44 #include "gromacs/simd/impl_x86_avx_256/impl_x86_avx_256_simd_double.h"
  45
  46 namespace gmx
  47 {
  48
  49 static inline SimdDouble gmx_simdcall
  50 fma(SimdDouble a, SimdDouble b, SimdDouble c)
  51 {
  52     return {
  53                _mm256_fmadd_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_)
  54     };
  55 }
  56
  57 static inline SimdDouble gmx_simdcall
  58 fms(SimdDouble a, SimdDouble b, SimdDouble c)
  59 {
  60     return {
  61                _mm256_fmsub_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_)
  62     };
  63 }
  64
  65 static inline SimdDouble gmx_simdcall
  66 fnma(SimdDouble a, SimdDouble b, SimdDouble c)
  67 {
  68     return {
  69                _mm256_fnmadd_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_)
  70     };
  71 }
  72
  73 static inline SimdDouble gmx_simdcall
  74 fnms(SimdDouble a, SimdDouble b, SimdDouble c)
  75 {
  76     return {
  77                _mm256_fnmsub_pd(a.simdInternal_, b.simdInternal_, c.simdInternal_)
  78     };
  79 }
  80
  81 static inline SimdDBool gmx_simdcall
  82 testBits(SimdDouble a)
  83 {
  84     __m256i ia  = _mm256_castpd_si256(a.simdInternal_);
  85     __m256i res = _mm256_andnot_si256( _mm256_cmpeq_epi64(ia, _mm256_setzero_si256()), _mm256_cmpeq_epi64(ia, ia));
  86
  87     return {
  88                _mm256_castsi256_pd(res)
  89     };
  90 }
  91
  92 static inline SimdDouble
  93 frexp(SimdDouble value, SimdDInt32 * exponent)
  94 {
  95     const __m256d  exponentMask = _mm256_castsi256_pd(_mm256_set1_epi64x(0x7FF0000000000000LL));
  96     const __m256d  mantissaMask = _mm256_castsi256_pd( _mm256_set1_epi64x(0x800FFFFFFFFFFFFFLL));
  97     const __m256i  exponentBias = _mm256_set1_epi64x(1022LL); // add 1 to make our definition identical to frexp()
  98     const __m256d  half         = _mm256_set1_pd(0.5);
  99     __m256i        iExponent;
 100     __m128i        iExponent128;
 101
 102     iExponent = _mm256_castpd_si256(_mm256_and_pd(value.simdInternal_, exponentMask));
 103     iExponent = _mm256_sub_epi64(_mm256_srli_epi64(iExponent, 52), exponentBias);
 104     iExponent = _mm256_shuffle_epi32(iExponent, _MM_SHUFFLE(3, 1, 2, 0));
 105
 106     iExponent128             = _mm256_extractf128_si256(iExponent, 1);
 107     exponent->simdInternal_  = _mm_unpacklo_epi64(_mm256_castsi256_si128(iExponent), iExponent128);
 108
 109     return {
 110                _mm256_or_pd(_mm256_and_pd(value.simdInternal_, mantissaMask), half)
 111     };
 112 }
 113
 114 template <MathOptimization opt = MathOptimization::Safe>
 115 static inline SimdDouble
 116 ldexp(SimdDouble value, SimdDInt32 exponent)
 117 {
 118     const __m128i  exponentBias = _mm_set1_epi32(1023);
 119     __m128i        iExponent    = _mm_add_epi32(exponent.simdInternal_, exponentBias);
 120
 121     if (opt == MathOptimization::Safe)
 122     {
 123         // Make sure biased argument is not negative
 124         iExponent = _mm_max_epi32(iExponent, _mm_setzero_si128());
 125     }
 126
 127     __m256i iExponent256 = _mm256_slli_epi64(_mm256_cvtepi32_epi64(iExponent), 52);
 128     return {
 129                _mm256_mul_pd(value.simdInternal_, _mm256_castsi256_pd(iExponent256))
 130     };
 131 }
 132
 133 }      // namespace gmx
 134
 135 #endif // GMX_SIMD_IMPL_X86_AVX2_256_SIMD_DOUBLE_H