src/gromacs/simd/impl_x86_avx_512/impl_x86_avx_512_util_float.h

   1 /*
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  36
  37 #ifndef GMX_SIMD_IMPL_X86_AVX_512_UTIL_FLOAT_H
  38 #define GMX_SIMD_IMPL_X86_AVX_512_UTIL_FLOAT_H
  39
  40 #include "config.h"
  41
  42 #include <cassert>
  43 #include <cstdint>
  44
  45 #include <immintrin.h>
  46
  47 #include "gromacs/utility/basedefinitions.h"
  48
  49 #include "impl_x86_avx_512_general.h"
  50 #include "impl_x86_avx_512_simd_float.h"
  51
  52 namespace gmx
  53 {
  54
  55 static const int c_simdBestPairAlignmentFloat = 2;
  56
  57 namespace
  58 {
  59 // Multiply function optimized for powers of 2, for which it is done by
  60 // shifting. Currently up to 8 is accelerated. Could be accelerated for any
  61 // number with a constexpr log2 function.
  62 template<int n>
  63 static inline SimdFInt32 fastMultiply(SimdFInt32 x)
  64 {
  65     if (n == 2)
  66     {
  67         return _mm512_slli_epi32(x.simdInternal_, 1);
  68     }
  69     else if (n == 4)
  70     {
  71         return _mm512_slli_epi32(x.simdInternal_, 2);
  72     }
  73     else if (n == 8)
  74     {
  75         return _mm512_slli_epi32(x.simdInternal_, 3);
  76     }
  77     else
  78     {
  79         return x * n;
  80     }
  81 }
  82
  83 template<int align>
  84 static inline void gmx_simdcall gatherLoadBySimdIntTranspose(const float*, SimdFInt32)
  85 {
  86     // Nothing to do. Termination of recursion.
  87 }
  88
  89 /* This is an internal helper function used by decr3Hsimd(...).
  90  */
  91 inline void gmx_simdcall decrHsimd(float* m, SimdFloat a)
  92 {
  93     __m256 t;
  94
  95     assert(std::size_t(m) % 32 == 0);
  96
  97     a.simdInternal_ = _mm512_add_ps(a.simdInternal_,
  98                                     _mm512_shuffle_f32x4(a.simdInternal_, a.simdInternal_, 0xEE));
  99     t               = _mm256_load_ps(m);
 100     t               = _mm256_sub_ps(t, _mm512_castps512_ps256(a.simdInternal_));
 101     _mm256_store_ps(m, t);
 102 }
 103 } // namespace
 104
 105 template<int align, typename... Targs>
 106 static inline void gmx_simdcall
 107                    gatherLoadBySimdIntTranspose(const float* base, SimdFInt32 offset, SimdFloat* v, Targs... Fargs)
 108 {
 109     // For align 1 or 2: No multiplication of offset is needed
 110     if (align > 2)
 111     {
 112         offset = fastMultiply<align>(offset);
 113     }
 114     // For align 2: Scale of 2*sizeof(float) is used (maximum supported scale)
 115     constexpr int align_ = (align > 2) ? 1 : align;
 116     v->simdInternal_     = _mm512_i32gather_ps(offset.simdInternal_, base, sizeof(float) * align_);
 117     // Gather remaining elements. Avoid extra multiplication (new align is 1 or 2).
 118     gatherLoadBySimdIntTranspose<align_>(base + 1, offset, Fargs...);
 119 }
 120
 121 template<int align, typename... Targs>
 122 static inline void gmx_simdcall
 123                    gatherLoadUBySimdIntTranspose(const float* base, SimdFInt32 offset, SimdFloat* v, Targs... Fargs)
 124 {
 125     gatherLoadBySimdIntTranspose<align>(base, offset, v, Fargs...);
 126 }
 127
 128 template<int align, typename... Targs>
 129 static inline void gmx_simdcall
 130                    gatherLoadTranspose(const float* base, const std::int32_t offset[], SimdFloat* v, Targs... Fargs)
 131 {
 132     gatherLoadBySimdIntTranspose<align>(base, simdLoad(offset, SimdFInt32Tag()), v, Fargs...);
 133 }
 134
 135 template<int align, typename... Targs>
 136 static inline void gmx_simdcall
 137                    gatherLoadUTranspose(const float* base, const std::int32_t offset[], SimdFloat* v, Targs... Fargs)
 138 {
 139     gatherLoadBySimdIntTranspose<align>(base, simdLoad(offset, SimdFInt32Tag()), v, Fargs...);
 140 }
 141
 142 template<int align>
 143 static inline void gmx_simdcall
 144                    transposeScatterStoreU(float* base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 145 {
 146     SimdFInt32 simdoffset = simdLoad(offset, SimdFInt32Tag());
 147     if (align > 2)
 148     {
 149         simdoffset = fastMultiply<align>(simdoffset);
 150     }
 151     constexpr size_t scale = (align > 2) ? sizeof(float) : sizeof(float) * align;
 152
 153     _mm512_i32scatter_ps(base, simdoffset.simdInternal_, v0.simdInternal_, scale);
 154     _mm512_i32scatter_ps(&(base[1]), simdoffset.simdInternal_, v1.simdInternal_, scale);
 155     _mm512_i32scatter_ps(&(base[2]), simdoffset.simdInternal_, v2.simdInternal_, scale);
 156 }
 157
 158 template<int align>
 159 static inline void gmx_simdcall
 160                    transposeScatterIncrU(float* base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 161 {
 162     __m512                                   t[4], t5, t6, t7, t8;
 163     int                                      i;
 164     alignas(GMX_SIMD_ALIGNMENT) std::int32_t o[16];
 165     store(o, fastMultiply<align>(simdLoad(offset, SimdFInt32Tag())));
 166     if (align < 4)
 167     {
 168         t5   = _mm512_unpacklo_ps(v0.simdInternal_, v1.simdInternal_);
 169         t6   = _mm512_unpackhi_ps(v0.simdInternal_, v1.simdInternal_);
 170         t[0] = _mm512_shuffle_ps(t5, v2.simdInternal_, _MM_SHUFFLE(0, 0, 1, 0));
 171         t[1] = _mm512_shuffle_ps(t5, v2.simdInternal_, _MM_SHUFFLE(1, 1, 3, 2));
 172         t[2] = _mm512_shuffle_ps(t6, v2.simdInternal_, _MM_SHUFFLE(2, 2, 1, 0));
 173         t[3] = _mm512_shuffle_ps(t6, v2.simdInternal_, _MM_SHUFFLE(3, 3, 3, 2));
 174         for (i = 0; i < 4; i++)
 175         {
 176             _mm512_mask_storeu_ps(base + o[i], avx512Int2Mask(7),
 177                                   _mm512_castps128_ps512(_mm_add_ps(_mm_loadu_ps(base + o[i]),
 178                                                                     _mm512_castps512_ps128(t[i]))));
 179             _mm512_mask_storeu_ps(base + o[4 + i], avx512Int2Mask(7),
 180                                   _mm512_castps128_ps512(_mm_add_ps(_mm_loadu_ps(base + o[4 + i]),
 181                                                                     _mm512_extractf32x4_ps(t[i], 1))));
 182             _mm512_mask_storeu_ps(base + o[8 + i], avx512Int2Mask(7),
 183                                   _mm512_castps128_ps512(_mm_add_ps(_mm_loadu_ps(base + o[8 + i]),
 184                                                                     _mm512_extractf32x4_ps(t[i], 2))));
 185             _mm512_mask_storeu_ps(base + o[12 + i], avx512Int2Mask(7),
 186                                   _mm512_castps128_ps512(_mm_add_ps(_mm_loadu_ps(base + o[12 + i]),
 187                                                                     _mm512_extractf32x4_ps(t[i], 3))));
 188         }
 189     }
 190     else
 191     {
 192         // One could use shuffle here too if it is OK to overwrite the padded elements for alignment
 193         t5   = _mm512_unpacklo_ps(v0.simdInternal_, v2.simdInternal_);
 194         t6   = _mm512_unpackhi_ps(v0.simdInternal_, v2.simdInternal_);
 195         t7   = _mm512_unpacklo_ps(v1.simdInternal_, _mm512_setzero_ps());
 196         t8   = _mm512_unpackhi_ps(v1.simdInternal_, _mm512_setzero_ps());
 197         t[0] = _mm512_unpacklo_ps(t5, t7); // x0 y0 z0  0 | x4 y4 z4 0
 198         t[1] = _mm512_unpackhi_ps(t5, t7); // x1 y1 z1  0 | x5 y5 z5 0
 199         t[2] = _mm512_unpacklo_ps(t6, t8); // x2 y2 z2  0 | x6 y6 z6 0
 200         t[3] = _mm512_unpackhi_ps(t6, t8); // x3 y3 z3  0 | x7 y7 z7 0
 201         if (align % 4 == 0)
 202         {
 203             for (i = 0; i < 4; i++)
 204             {
 205                 _mm_store_ps(base + o[i],
 206                              _mm_add_ps(_mm_load_ps(base + o[i]), _mm512_castps512_ps128(t[i])));
 207                 _mm_store_ps(base + o[4 + i],
 208                              _mm_add_ps(_mm_load_ps(base + o[4 + i]), _mm512_extractf32x4_ps(t[i], 1)));
 209                 _mm_store_ps(base + o[8 + i],
 210                              _mm_add_ps(_mm_load_ps(base + o[8 + i]), _mm512_extractf32x4_ps(t[i], 2)));
 211                 _mm_store_ps(base + o[12 + i], _mm_add_ps(_mm_load_ps(base + o[12 + i]),
 212                                                           _mm512_extractf32x4_ps(t[i], 3)));
 213             }
 214         }
 215         else
 216         {
 217             for (i = 0; i < 4; i++)
 218             {
 219                 _mm_storeu_ps(base + o[i],
 220                               _mm_add_ps(_mm_loadu_ps(base + o[i]), _mm512_castps512_ps128(t[i])));
 221                 _mm_storeu_ps(base + o[4 + i], _mm_add_ps(_mm_loadu_ps(base + o[4 + i]),
 222                                                           _mm512_extractf32x4_ps(t[i], 1)));
 223                 _mm_storeu_ps(base + o[8 + i], _mm_add_ps(_mm_loadu_ps(base + o[8 + i]),
 224                                                           _mm512_extractf32x4_ps(t[i], 2)));
 225                 _mm_storeu_ps(base + o[12 + i], _mm_add_ps(_mm_loadu_ps(base + o[12 + i]),
 226                                                            _mm512_extractf32x4_ps(t[i], 3)));
 227             }
 228         }
 229     }
 230 }
 231
 232 template<int align>
 233 static inline void gmx_simdcall
 234                    transposeScatterDecrU(float* base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 235 {
 236     __m512                                   t[4], t5, t6, t7, t8;
 237     int                                      i;
 238     alignas(GMX_SIMD_ALIGNMENT) std::int32_t o[16];
 239     store(o, fastMultiply<align>(simdLoad(offset, SimdFInt32Tag())));
 240     if (align < 4)
 241     {
 242         t5   = _mm512_unpacklo_ps(v0.simdInternal_, v1.simdInternal_);
 243         t6   = _mm512_unpackhi_ps(v0.simdInternal_, v1.simdInternal_);
 244         t[0] = _mm512_shuffle_ps(t5, v2.simdInternal_, _MM_SHUFFLE(0, 0, 1, 0));
 245         t[1] = _mm512_shuffle_ps(t5, v2.simdInternal_, _MM_SHUFFLE(1, 1, 3, 2));
 246         t[2] = _mm512_shuffle_ps(t6, v2.simdInternal_, _MM_SHUFFLE(2, 2, 1, 0));
 247         t[3] = _mm512_shuffle_ps(t6, v2.simdInternal_, _MM_SHUFFLE(3, 3, 3, 2));
 248         for (i = 0; i < 4; i++)
 249         {
 250             _mm512_mask_storeu_ps(base + o[i], avx512Int2Mask(7),
 251                                   _mm512_castps128_ps512(_mm_sub_ps(_mm_loadu_ps(base + o[i]),
 252                                                                     _mm512_castps512_ps128(t[i]))));
 253             _mm512_mask_storeu_ps(base + o[4 + i], avx512Int2Mask(7),
 254                                   _mm512_castps128_ps512(_mm_sub_ps(_mm_loadu_ps(base + o[4 + i]),
 255                                                                     _mm512_extractf32x4_ps(t[i], 1))));
 256             _mm512_mask_storeu_ps(base + o[8 + i], avx512Int2Mask(7),
 257                                   _mm512_castps128_ps512(_mm_sub_ps(_mm_loadu_ps(base + o[8 + i]),
 258                                                                     _mm512_extractf32x4_ps(t[i], 2))));
 259             _mm512_mask_storeu_ps(base + o[12 + i], avx512Int2Mask(7),
 260                                   _mm512_castps128_ps512(_mm_sub_ps(_mm_loadu_ps(base + o[12 + i]),
 261                                                                     _mm512_extractf32x4_ps(t[i], 3))));
 262         }
 263     }
 264     else
 265     {
 266         // One could use shuffle here too if it is OK to overwrite the padded elements for alignment
 267         t5   = _mm512_unpacklo_ps(v0.simdInternal_, v2.simdInternal_);
 268         t6   = _mm512_unpackhi_ps(v0.simdInternal_, v2.simdInternal_);
 269         t7   = _mm512_unpacklo_ps(v1.simdInternal_, _mm512_setzero_ps());
 270         t8   = _mm512_unpackhi_ps(v1.simdInternal_, _mm512_setzero_ps());
 271         t[0] = _mm512_unpacklo_ps(t5, t7); // x0 y0 z0  0 | x4 y4 z4 0
 272         t[1] = _mm512_unpackhi_ps(t5, t7); // x1 y1 z1  0 | x5 y5 z5 0
 273         t[2] = _mm512_unpacklo_ps(t6, t8); // x2 y2 z2  0 | x6 y6 z6 0
 274         t[3] = _mm512_unpackhi_ps(t6, t8); // x3 y3 z3  0 | x7 y7 z7 0
 275         if (align % 4 == 0)
 276         {
 277             for (i = 0; i < 4; i++)
 278             {
 279                 _mm_store_ps(base + o[i],
 280                              _mm_sub_ps(_mm_load_ps(base + o[i]), _mm512_castps512_ps128(t[i])));
 281                 _mm_store_ps(base + o[4 + i],
 282                              _mm_sub_ps(_mm_load_ps(base + o[4 + i]), _mm512_extractf32x4_ps(t[i], 1)));
 283                 _mm_store_ps(base + o[8 + i],
 284                              _mm_sub_ps(_mm_load_ps(base + o[8 + i]), _mm512_extractf32x4_ps(t[i], 2)));
 285                 _mm_store_ps(base + o[12 + i], _mm_sub_ps(_mm_load_ps(base + o[12 + i]),
 286                                                           _mm512_extractf32x4_ps(t[i], 3)));
 287             }
 288         }
 289         else
 290         {
 291             for (i = 0; i < 4; i++)
 292             {
 293                 _mm_storeu_ps(base + o[i],
 294                               _mm_sub_ps(_mm_loadu_ps(base + o[i]), _mm512_castps512_ps128(t[i])));
 295                 _mm_storeu_ps(base + o[4 + i], _mm_sub_ps(_mm_loadu_ps(base + o[4 + i]),
 296                                                           _mm512_extractf32x4_ps(t[i], 1)));
 297                 _mm_storeu_ps(base + o[8 + i], _mm_sub_ps(_mm_loadu_ps(base + o[8 + i]),
 298                                                           _mm512_extractf32x4_ps(t[i], 2)));
 299                 _mm_storeu_ps(base + o[12 + i], _mm_sub_ps(_mm_loadu_ps(base + o[12 + i]),
 300                                                            _mm512_extractf32x4_ps(t[i], 3)));
 301             }
 302         }
 303     }
 304 }
 305
 306 static inline void gmx_simdcall expandScalarsToTriplets(SimdFloat  scalar,
 307                                                         SimdFloat* triplets0,
 308                                                         SimdFloat* triplets1,
 309                                                         SimdFloat* triplets2)
 310 {
 311     triplets0->simdInternal_ = _mm512_permutexvar_ps(
 312             _mm512_set_epi32(5, 4, 4, 4, 3, 3, 3, 2, 2, 2, 1, 1, 1, 0, 0, 0), scalar.simdInternal_);
 313     triplets1->simdInternal_ = _mm512_permutexvar_ps(
 314             _mm512_set_epi32(10, 10, 9, 9, 9, 8, 8, 8, 7, 7, 7, 6, 6, 6, 5, 5), scalar.simdInternal_);
 315     triplets2->simdInternal_ = _mm512_permutexvar_ps(
 316             _mm512_set_epi32(15, 15, 15, 14, 14, 14, 13, 13, 13, 12, 12, 12, 11, 11, 11, 10),
 317             scalar.simdInternal_);
 318 }
 319
 320
 321 static inline float gmx_simdcall reduceIncr4ReturnSum(float* m, SimdFloat v0, SimdFloat v1, SimdFloat v2, SimdFloat v3)
 322 {
 323     __m512 t0, t1, t2;
 324     __m128 t3, t4;
 325
 326     assert(std::size_t(m) % 16 == 0);
 327
 328     t0 = _mm512_add_ps(v0.simdInternal_, _mm512_permute_ps(v0.simdInternal_, 0x4E));
 329     t0 = _mm512_mask_add_ps(t0, avx512Int2Mask(0xCCCC), v2.simdInternal_,
 330                             _mm512_permute_ps(v2.simdInternal_, 0x4E));
 331     t1 = _mm512_add_ps(v1.simdInternal_, _mm512_permute_ps(v1.simdInternal_, 0x4E));
 332     t1 = _mm512_mask_add_ps(t1, avx512Int2Mask(0xCCCC), v3.simdInternal_,
 333                             _mm512_permute_ps(v3.simdInternal_, 0x4E));
 334     t2 = _mm512_add_ps(t0, _mm512_permute_ps(t0, 0xB1));
 335     t2 = _mm512_mask_add_ps(t2, avx512Int2Mask(0xAAAA), t1, _mm512_permute_ps(t1, 0xB1));
 336
 337     t2 = _mm512_add_ps(t2, _mm512_shuffle_f32x4(t2, t2, 0x4E));
 338     t2 = _mm512_add_ps(t2, _mm512_shuffle_f32x4(t2, t2, 0xB1));
 339
 340     t3 = _mm512_castps512_ps128(t2);
 341     t4 = _mm_load_ps(m);
 342     t4 = _mm_add_ps(t4, t3);
 343     _mm_store_ps(m, t4);
 344
 345     t3 = _mm_add_ps(t3, _mm_permute_ps(t3, 0x4E));
 346     t3 = _mm_add_ps(t3, _mm_permute_ps(t3, 0xB1));
 347
 348     return _mm_cvtss_f32(t3);
 349 }
 350
 351 static inline SimdFloat gmx_simdcall loadDualHsimd(const float* m0, const float* m1)
 352 {
 353     assert(std::size_t(m0) % 32 == 0);
 354     assert(std::size_t(m1) % 32 == 0);
 355
 356     return { _mm512_castpd_ps(_mm512_insertf64x4(
 357             _mm512_castpd256_pd512(_mm256_load_pd(reinterpret_cast<const double*>(m0))),
 358             _mm256_load_pd(reinterpret_cast<const double*>(m1)), 1)) };
 359 }
 360
 361 static inline SimdFloat gmx_simdcall loadDuplicateHsimd(const float* m)
 362 {
 363     assert(std::size_t(m) % 32 == 0);
 364     return { _mm512_castpd_ps(_mm512_broadcast_f64x4(_mm256_load_pd(reinterpret_cast<const double*>(m)))) };
 365 }
 366
 367 static inline SimdFloat gmx_simdcall loadU1DualHsimd(const float* m)
 368 {
 369     return { _mm512_shuffle_f32x4(_mm512_broadcastss_ps(_mm_load_ss(m)),
 370                                   _mm512_broadcastss_ps(_mm_load_ss(m + 1)), 0x44) };
 371 }
 372
 373
 374 static inline void gmx_simdcall storeDualHsimd(float* m0, float* m1, SimdFloat a)
 375 {
 376     assert(std::size_t(m0) % 32 == 0);
 377     assert(std::size_t(m1) % 32 == 0);
 378
 379     _mm256_store_ps(m0, _mm512_castps512_ps256(a.simdInternal_));
 380     _mm256_store_pd(reinterpret_cast<double*>(m1),
 381                     _mm512_extractf64x4_pd(_mm512_castps_pd(a.simdInternal_), 1));
 382 }
 383
 384 static inline void gmx_simdcall incrDualHsimd(float* m0, float* m1, SimdFloat a)
 385 {
 386     assert(std::size_t(m0) % 32 == 0);
 387     assert(std::size_t(m1) % 32 == 0);
 388
 389     __m256 x;
 390
 391     // Lower half
 392     x = _mm256_load_ps(m0);
 393     x = _mm256_add_ps(x, _mm512_castps512_ps256(a.simdInternal_));
 394     _mm256_store_ps(m0, x);
 395
 396     // Upper half
 397     x = _mm256_load_ps(m1);
 398     x = _mm256_add_ps(x, _mm256_castpd_ps(_mm512_extractf64x4_pd(_mm512_castps_pd(a.simdInternal_), 1)));
 399     _mm256_store_ps(m1, x);
 400 }
 401
 402 static inline void gmx_simdcall decr3Hsimd(float* m, SimdFloat a0, SimdFloat a1, SimdFloat a2)
 403 {
 404     decrHsimd(m, a0);
 405     decrHsimd(m + GMX_SIMD_FLOAT_WIDTH / 2, a1);
 406     decrHsimd(m + GMX_SIMD_FLOAT_WIDTH, a2);
 407 }
 408
 409
 410 template<int align>
 411 static inline void gmx_simdcall gatherLoadTransposeHsimd(const float*       base0,
 412                                                          const float*       base1,
 413                                                          const std::int32_t offset[],
 414                                                          SimdFloat*         v0,
 415                                                          SimdFloat*         v1)
 416 {
 417     __m256i idx;
 418     __m512  tmp1, tmp2;
 419
 420     assert(std::size_t(offset) % 32 == 0);
 421     assert(std::size_t(base0) % 8 == 0);
 422     assert(std::size_t(base1) % 8 == 0);
 423
 424     idx = _mm256_load_si256(reinterpret_cast<const __m256i*>(offset));
 425
 426     static_assert(align == 2 || align == 4, "If more are needed use fastMultiply");
 427     if (align == 4)
 428     {
 429         idx = _mm256_slli_epi32(idx, 1);
 430     }
 431
 432     tmp1 = _mm512_castpd_ps(
 433             _mm512_i32gather_pd(idx, reinterpret_cast<const double*>(base0), sizeof(double)));
 434     tmp2 = _mm512_castpd_ps(
 435             _mm512_i32gather_pd(idx, reinterpret_cast<const double*>(base1), sizeof(double)));
 436
 437     v0->simdInternal_ = _mm512_mask_moveldup_ps(tmp1, 0xAAAA, tmp2);
 438     v1->simdInternal_ = _mm512_mask_movehdup_ps(tmp2, 0x5555, tmp1);
 439
 440     v0->simdInternal_ = _mm512_permutexvar_ps(
 441             _mm512_set_epi32(15, 13, 11, 9, 7, 5, 3, 1, 14, 12, 10, 8, 6, 4, 2, 0), v0->simdInternal_);
 442     v1->simdInternal_ = _mm512_permutexvar_ps(
 443             _mm512_set_epi32(15, 13, 11, 9, 7, 5, 3, 1, 14, 12, 10, 8, 6, 4, 2, 0), v1->simdInternal_);
 444 }
 445
 446 static inline float gmx_simdcall reduceIncr4ReturnSumHsimd(float* m, SimdFloat v0, SimdFloat v1)
 447 {
 448     __m512 t0, t1;
 449     __m128 t2, t3;
 450
 451     assert(std::size_t(m) % 16 == 0);
 452
 453     t0 = _mm512_shuffle_f32x4(v0.simdInternal_, v1.simdInternal_, 0x88);
 454     t1 = _mm512_shuffle_f32x4(v0.simdInternal_, v1.simdInternal_, 0xDD);
 455     t0 = _mm512_add_ps(t0, t1);
 456     t0 = _mm512_add_ps(t0, _mm512_permute_ps(t0, 0x4E));
 457     t0 = _mm512_add_ps(t0, _mm512_permute_ps(t0, 0xB1));
 458     t0 = _mm512_maskz_compress_ps(avx512Int2Mask(0x1111), t0);
 459
 460     t3 = _mm512_castps512_ps128(t0);
 461     t2 = _mm_load_ps(m);
 462     t2 = _mm_add_ps(t2, t3);
 463     _mm_store_ps(m, t2);
 464
 465     t3 = _mm_add_ps(t3, _mm_permute_ps(t3, 0x4E));
 466     t3 = _mm_add_ps(t3, _mm_permute_ps(t3, 0xB1));
 467
 468     return _mm_cvtss_f32(t3);
 469 }
 470
 471 static inline SimdFloat gmx_simdcall loadUNDuplicate4(const float* f)
 472 {
 473     return { _mm512_permute_ps(_mm512_maskz_expandloadu_ps(0x1111, f), 0) };
 474 }
 475
 476 static inline SimdFloat gmx_simdcall load4DuplicateN(const float* f)
 477 {
 478     return { _mm512_broadcast_f32x4(_mm_load_ps(f)) };
 479 }
 480
 481 static inline SimdFloat gmx_simdcall loadU4NOffset(const float* f, int offset)
 482 {
 483     const __m256i idx = _mm256_setr_epi32(0, 0, 1, 1, 2, 2, 3, 3);
 484     const __m256i gdx = _mm256_add_epi32(_mm256_setr_epi32(0, 2, 0, 2, 0, 2, 0, 2),
 485                                          _mm256_mullo_epi32(idx, _mm256_set1_epi32(offset)));
 486     return { _mm512_castpd_ps(_mm512_i32gather_pd(gdx, reinterpret_cast<const double*>(f), sizeof(float))) };
 487 }
 488
 489 } // namespace gmx
 490
 491 #endif // GMX_SIMD_IMPL_X86_AVX_512_UTIL_FLOAT_H