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37 #ifndef _nbnxn_kernel_simd_utils_x86_256d_h_
38 #define _nbnxn_kernel_simd_utils_x86_256d_h_
40 /* This files contains all functions/macros for the SIMD kernels
41 * which have explicit dependencies on the j-cluster size and/or SIMD-width.
42 * The functionality which depends on the j-cluster size is:
45 * energy group pair energy storage
48 /* Transpose 2 double precision registers */
49 static gmx_inline void
50 gmx_mm_transpose2_op_pd(__m128d in0, __m128d in1,
51 __m128d *out0, __m128d *out1)
53 *out0 = _mm_unpacklo_pd(in0, in1);
54 *out1 = _mm_unpackhi_pd(in0, in1);
57 /* Sum the elements within each input register and store the sums in out */
58 static gmx_inline __m256d
59 gmx_mm_transpose_sum4_pr(__m256d in0, __m256d in1,
60 __m256d in2, __m256d in3)
62 in0 = _mm256_hadd_pd(in0, in1);
63 in2 = _mm256_hadd_pd(in2, in3);
65 return _mm256_add_pd(_mm256_permute2f128_pd(in0, in2, 0x20), _mm256_permute2f128_pd(in0, in2, 0x31));
68 static gmx_inline __m256
69 gmx_mm256_invsqrt_ps_single(__m256 x)
71 const __m256 half = _mm256_set_ps(0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5);
72 const __m256 three = _mm256_set_ps(3.0, 3.0, 3.0, 3.0, 3.0, 3.0, 3.0, 3.0);
74 __m256 lu = _mm256_rsqrt_ps(x);
76 return _mm256_mul_ps(half, _mm256_mul_ps(_mm256_sub_ps(three, _mm256_mul_ps(_mm256_mul_ps(lu, lu), x)), lu));
79 /* Put two 128-bit 4-float registers into one 256-bit 8-float register */
80 static gmx_inline __m256
81 gmx_2_m128_to_m256(__m128 in0, __m128 in1)
83 return _mm256_insertf128_ps(_mm256_castps128_ps256(in0), in1, 1);
86 /* Put two 128-bit 2-double registers into one 256-bit 4-double register */
87 static gmx_inline __m256d
88 gmx_2_m128d_to_m256d(__m128d in0, __m128d in1)
90 return _mm256_insertf128_pd(_mm256_castpd128_pd256(in0), in1, 1);
93 /* Do 2 double precision invsqrt operations.
94 * Doing the SIMD rsqrt and the first Newton Raphson iteration
95 * in single precision gives full double precision accuracy.
97 static gmx_inline void
98 gmx_mm_invsqrt2_pd(__m256d in0, __m256d in1,
99 __m256d *out0, __m256d *out1)
101 const __m256d half = _mm256_set1_pd(0.5);
102 const __m256d three = _mm256_set1_pd(3.0);
106 s = gmx_2_m128_to_m256(_mm256_cvtpd_ps(in0), _mm256_cvtpd_ps(in1));
107 ir = gmx_mm256_invsqrt_ps_single(s);
108 lu0 = _mm256_cvtps_pd(_mm256_castps256_ps128(ir));
109 lu1 = _mm256_cvtps_pd(_mm256_extractf128_ps(ir, 1));
110 *out0 = _mm256_mul_pd(half, _mm256_mul_pd(_mm256_sub_pd(three, _mm256_mul_pd(_mm256_mul_pd(lu0, lu0), in0)), lu0));
111 *out1 = _mm256_mul_pd(half, _mm256_mul_pd(_mm256_sub_pd(three, _mm256_mul_pd(_mm256_mul_pd(lu1, lu1), in1)), lu1));
114 static gmx_inline void
115 load_lj_pair_params(const real *nbfp, const int *type, int aj,
116 __m256d *c6_S, __m256d *c12_S)
118 __m128d clj_S[UNROLLJ], c6t_S[2], c12t_S[2];
121 for (p = 0; p < UNROLLJ; p++)
123 clj_S[p] = _mm_load_pd(nbfp+type[aj+p]*NBFP_STRIDE);
125 gmx_mm_transpose2_op_pd(clj_S[0], clj_S[1], &c6t_S[0], &c12t_S[0]);
126 gmx_mm_transpose2_op_pd(clj_S[2], clj_S[3], &c6t_S[1], &c12t_S[1]);
127 *c6_S = gmx_2_m128d_to_m256d(c6t_S[0], c6t_S[1]);
128 *c12_S = gmx_2_m128d_to_m256d(c12t_S[0], c12t_S[1]);
131 static gmx_inline void
132 load_table_f(const real *tab_coul_F, __m128i ti_S, int *ti,
133 __m256d *ctab0_S, __m256d *ctab1_S)
135 __m128d ctab_S[4], tr_S[4];
138 _mm_store_si128((__m128i *)ti, ti_S);
139 for (j = 0; j < 4; j++)
141 ctab_S[j] = _mm_loadu_pd(tab_coul_F+ti[j]);
143 /* Shuffle the force table entries to a convenient order */
144 gmx_mm_transpose2_op_pd(ctab_S[0], ctab_S[1], &tr_S[0], &tr_S[1]);
145 gmx_mm_transpose2_op_pd(ctab_S[2], ctab_S[3], &tr_S[2], &tr_S[3]);
146 *ctab0_S = gmx_2_m128d_to_m256d(tr_S[0], tr_S[2]);
147 *ctab1_S = gmx_2_m128d_to_m256d(tr_S[1], tr_S[3]);
148 /* The second force table entry should contain the difference */
149 *ctab1_S = _mm256_sub_pd(*ctab1_S, *ctab0_S);
152 static gmx_inline void
153 load_table_f_v(const real *tab_coul_F, const real *tab_coul_V,
154 __m128i ti_S, int *ti,
155 __m256d *ctab0_S, __m256d *ctab1_S, __m256d *ctabv_S)
157 __m128d ctab_S[8], tr_S[4];
160 _mm_store_si128((__m128i *)ti, ti_S);
161 for (j = 0; j < 4; j++)
163 ctab_S[j] = _mm_loadu_pd(tab_coul_F+ti[j]);
165 /* Shuffle the force table entries to a convenient order */
166 gmx_mm_transpose2_op_pd(ctab_S[0], ctab_S[1], &tr_S[0], &tr_S[1]);
167 gmx_mm_transpose2_op_pd(ctab_S[2], ctab_S[3], &tr_S[2], &tr_S[3]);
168 *ctab0_S = gmx_2_m128d_to_m256d(tr_S[0], tr_S[2]);
169 *ctab1_S = gmx_2_m128d_to_m256d(tr_S[1], tr_S[3]);
170 /* The second force table entry should contain the difference */
171 *ctab1_S = _mm256_sub_pd(*ctab1_S, *ctab0_S);
173 for (j = 0; j < 4; j++)
175 ctab_S[4+j] = _mm_loadu_pd(tab_coul_V+ti[j]);
177 /* Shuffle the energy table entries to a single register */
178 *ctabv_S = gmx_2_m128d_to_m256d(_mm_shuffle_pd(ctab_S[4], ctab_S[5], _MM_SHUFFLE2(0, 0)), _mm_shuffle_pd(ctab_S[6], ctab_S[7], _MM_SHUFFLE2(0, 0)));
181 #endif /* _nbnxn_kernel_simd_utils_x86_s256d_h_ */