runner_doiact_vec.c 41.5 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
/*******************************************************************************
 * This file is part of SWIFT.
 * Copyright (c) 2016 James Willis (james.s.willis@durham.ac.uk)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 ******************************************************************************/

/* Config parameters. */
#include "../config.h"

/* This object's header. */
#include "runner_doiact_vec.h"

26
27
28
/* Local headers. */
#include "active.h"

29
30
31
#ifdef WITH_VECTORIZATION
static const vector kernel_gamma2_vec = FILL_VEC(kernel_gamma2);

James Willis's avatar
James Willis committed
32
33
34
/**
 * @brief Compute the vector remainder interactions from the secondary cache.
 *
Matthieu Schaller's avatar
Matthieu Schaller committed
35
 * @param int_cache (return) secondary #cache of interactions between two
James Willis's avatar
James Willis committed
36
 * particles.
James Willis's avatar
James Willis committed
37
 * @param icount Interaction count.
Matthieu Schaller's avatar
Matthieu Schaller committed
38
 * @param rhoSum (return) #vector holding the cumulative sum of the density
James Willis's avatar
James Willis committed
39
 * update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
40
 * @param rho_dhSum (return) #vector holding the cumulative sum of the density
James Willis's avatar
James Willis committed
41
 * gradient update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
42
 * @param wcountSum (return) #vector holding the cumulative sum of the wcount
James Willis's avatar
James Willis committed
43
 * update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
44
 * @param wcount_dhSum (return) #vector holding the cumulative sum of the wcount
James Willis's avatar
James Willis committed
45
 * gradient update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
46
 * @param div_vSum (return) #vector holding the cumulative sum of the divergence
James Willis's avatar
James Willis committed
47
 * update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
48
 * @param curlvxSum (return) #vector holding the cumulative sum of the curl of
James Willis's avatar
James Willis committed
49
 * vx update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
50
 * @param curlvySum (return) #vector holding the cumulative sum of the curl of
James Willis's avatar
James Willis committed
51
 * vy update on pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
52
 * @param curlvzSum (return) #vector holding the cumulative sum of the curl of
James Willis's avatar
James Willis committed
53
 * vz update on pi.
James Willis's avatar
James Willis committed
54
55
56
57
 * @param v_hi_inv #vector of 1/h for pi.
 * @param v_vix #vector of x velocity of pi.
 * @param v_viy #vector of y velocity of pi.
 * @param v_viz #vector of z velocity of pi.
Matthieu Schaller's avatar
Matthieu Schaller committed
58
 * @param icount_align (return) Interaction count after the remainder
James Willis's avatar
James Willis committed
59
 * interactions have been performed, should be a multiple of the vector length.
James Willis's avatar
James Willis committed
60
 */
James Willis's avatar
James Willis committed
61
__attribute__((always_inline)) INLINE static void calcRemInteractions(
Matthieu Schaller's avatar
Matthieu Schaller committed
62
63
64
65
66
    struct c2_cache *const int_cache, const int icount, vector *rhoSum,
    vector *rho_dhSum, vector *wcountSum, vector *wcount_dhSum,
    vector *div_vSum, vector *curlvxSum, vector *curlvySum, vector *curlvzSum,
    vector v_hi_inv, vector v_vix, vector v_viy, vector v_viz,
    int *icount_align) {
67

68
  mask_t int_mask, int_mask2;
James Willis's avatar
James Willis committed
69
70

  /* Work out the number of remainder interactions and pad secondary cache. */
71
72
73
74
75
76
  *icount_align = icount;
  int rem = icount % (NUM_VEC_PROC * VEC_SIZE);
  if (rem != 0) {
    int pad = (NUM_VEC_PROC * VEC_SIZE) - rem;
    *icount_align += pad;

77
    /* Initialise masks to true. */
78
79
    vec_init_mask_true(int_mask);
    vec_init_mask_true(int_mask2);
80

James Willis's avatar
James Willis committed
81
82
83
    /* Pad secondary cache so that there are no contributions in the interaction
     * function. */
    for (int i = icount; i < *icount_align; i++) {
84
85
86
87
88
89
90
91
      int_cache->mq[i] = 0.f;
      int_cache->r2q[i] = 1.f;
      int_cache->dxq[i] = 0.f;
      int_cache->dyq[i] = 0.f;
      int_cache->dzq[i] = 0.f;
      int_cache->vxq[i] = 0.f;
      int_cache->vyq[i] = 0.f;
      int_cache->vzq[i] = 0.f;
92
93
94
95
    }

    /* Zero parts of mask that represent the padded values.*/
    if (pad < VEC_SIZE) {
James Willis's avatar
James Willis committed
96
      vec_pad_mask(int_mask2, pad);
James Willis's avatar
James Willis committed
97
    } else {
James Willis's avatar
James Willis committed
98
      vec_pad_mask(int_mask, VEC_SIZE - rem);
99
      vec_zero_mask(int_mask2);
100
101
    }

James Willis's avatar
James Willis committed
102
103
    /* Perform remainder interaction and remove remainder from aligned
     * interaction count. */
104
    *icount_align = icount - rem;
James Willis's avatar
James Willis committed
105
106
107
108
109
110
    runner_iact_nonsym_2_vec_density(
        &int_cache->r2q[*icount_align], &int_cache->dxq[*icount_align],
        &int_cache->dyq[*icount_align], &int_cache->dzq[*icount_align],
        v_hi_inv, v_vix, v_viy, v_viz, &int_cache->vxq[*icount_align],
        &int_cache->vyq[*icount_align], &int_cache->vzq[*icount_align],
        &int_cache->mq[*icount_align], rhoSum, rho_dhSum, wcountSum,
James Willis's avatar
James Willis committed
111
112
        wcount_dhSum, div_vSum, curlvxSum, curlvySum, curlvzSum, int_mask,
        int_mask2, 1);
113
114
115
  }
}

James Willis's avatar
James Willis committed
116
/**
James Willis's avatar
James Willis committed
117
118
 * @brief Left-packs the values needed by an interaction into the secondary
 * cache (Supports AVX, AVX2 and AVX512 instruction sets).
James Willis's avatar
James Willis committed
119
120
 *
 * @param mask Contains which particles need to interact.
Matthieu Schaller's avatar
Matthieu Schaller committed
121
 * @param pjd Index of the particle to store into.
James Willis's avatar
James Willis committed
122
123
124
125
126
 * @param v_r2 #vector of the separation between two particles squared.
 * @param v_dx #vector of the x separation between two particles.
 * @param v_dy #vector of the y separation between two particles.
 * @param v_dz #vector of the z separation between two particles.
 * @param cell_cache #cache of all particles in the cell.
Matthieu Schaller's avatar
Matthieu Schaller committed
127
 * @param int_cache (return) secondary #cache of interactions between two
James Willis's avatar
James Willis committed
128
 * particles.
James Willis's avatar
James Willis committed
129
130
 * @param icount Interaction count.
 * @param rhoSum #vector holding the cumulative sum of the density update on pi.
James Willis's avatar
James Willis committed
131
132
133
134
135
136
137
138
139
140
141
142
143
144
 * @param rho_dhSum #vector holding the cumulative sum of the density gradient
 * update on pi.
 * @param wcountSum #vector holding the cumulative sum of the wcount update on
 * pi.
 * @param wcount_dhSum #vector holding the cumulative sum of the wcount gradient
 * update on pi.
 * @param div_vSum #vector holding the cumulative sum of the divergence update
 * on pi.
 * @param curlvxSum #vector holding the cumulative sum of the curl of vx update
 * on pi.
 * @param curlvySum #vector holding the cumulative sum of the curl of vy update
 * on pi.
 * @param curlvzSum #vector holding the cumulative sum of the curl of vz update
 * on pi.
James Willis's avatar
James Willis committed
145
146
147
148
149
 * @param v_hi_inv #vector of 1/h for pi.
 * @param v_vix #vector of x velocity of pi.
 * @param v_viy #vector of y velocity of pi.
 * @param v_viz #vector of z velocity of pi.
 */
James Willis's avatar
James Willis committed
150
__attribute__((always_inline)) INLINE static void storeInteractions(
151
    const int mask, const int pjd, vector *v_r2, vector *v_dx, vector *v_dy,
James Willis's avatar
James Willis committed
152
153
154
155
156
    vector *v_dz, const struct cache *const cell_cache,
    struct c2_cache *const int_cache, int *icount, vector *rhoSum,
    vector *rho_dhSum, vector *wcountSum, vector *wcount_dhSum,
    vector *div_vSum, vector *curlvxSum, vector *curlvySum, vector *curlvzSum,
    vector v_hi_inv, vector v_vix, vector v_viy, vector v_viz) {
James Willis's avatar
James Willis committed
157
158
159

/* Left-pack values needed into the secondary cache using the interaction mask.
 */
160
#if defined(HAVE_AVX2) || defined(HAVE_AVX512_F)
161
162
163
164
165
166
167
  mask_t packed_mask;
  VEC_FORM_PACKED_MASK(mask, packed_mask);

  VEC_LEFT_PACK(v_r2->v, packed_mask, &int_cache->r2q[*icount]);
  VEC_LEFT_PACK(v_dx->v, packed_mask, &int_cache->dxq[*icount]);
  VEC_LEFT_PACK(v_dy->v, packed_mask, &int_cache->dyq[*icount]);
  VEC_LEFT_PACK(v_dz->v, packed_mask, &int_cache->dzq[*icount]);
James Willis's avatar
James Willis committed
168
169
170
171
172
173
174
175
  VEC_LEFT_PACK(vec_load(&cell_cache->m[pjd]), packed_mask,
                &int_cache->mq[*icount]);
  VEC_LEFT_PACK(vec_load(&cell_cache->vx[pjd]), packed_mask,
                &int_cache->vxq[*icount]);
  VEC_LEFT_PACK(vec_load(&cell_cache->vy[pjd]), packed_mask,
                &int_cache->vyq[*icount]);
  VEC_LEFT_PACK(vec_load(&cell_cache->vz[pjd]), packed_mask,
                &int_cache->vzq[*icount]);
176
177
178

  /* Increment interaction count by number of bits set in mask. */
  (*icount) += __builtin_popcount(mask);
179
#else
James Willis's avatar
James Willis committed
180
  /* Quicker to do it serially in AVX rather than use intrinsics. */
James Willis's avatar
James Willis committed
181
  for (int bit_index = 0; bit_index < VEC_SIZE; bit_index++) {
182
183
    if (mask & (1 << bit_index)) {
      /* Add this interaction to the queue. */
184
185
186
187
188
189
190
191
      int_cache->r2q[*icount] = v_r2->f[bit_index];
      int_cache->dxq[*icount] = v_dx->f[bit_index];
      int_cache->dyq[*icount] = v_dy->f[bit_index];
      int_cache->dzq[*icount] = v_dz->f[bit_index];
      int_cache->mq[*icount] = cell_cache->m[pjd + bit_index];
      int_cache->vxq[*icount] = cell_cache->vx[pjd + bit_index];
      int_cache->vyq[*icount] = cell_cache->vy[pjd + bit_index];
      int_cache->vzq[*icount] = cell_cache->vz[pjd + bit_index];
192
193
194
195

      (*icount)++;
    }
  }
196

James Willis's avatar
James Willis committed
197
198
#endif /* defined(HAVE_AVX2) || defined(HAVE_AVX512_F) */

James Willis's avatar
James Willis committed
199
  /* Flush the c2 cache if it has reached capacity. */
James Willis's avatar
James Willis committed
200
  if (*icount >= (C2_CACHE_SIZE - (NUM_VEC_PROC * VEC_SIZE))) {
201
202

    int icount_align = *icount;
James Willis's avatar
James Willis committed
203

James Willis's avatar
James Willis committed
204
    /* Peform remainder interactions. */
Matthieu Schaller's avatar
Matthieu Schaller committed
205
206
207
    calcRemInteractions(int_cache, *icount, rhoSum, rho_dhSum, wcountSum,
                        wcount_dhSum, div_vSum, curlvxSum, curlvySum, curlvzSum,
                        v_hi_inv, v_vix, v_viy, v_viz, &icount_align);
208

209
    mask_t int_mask, int_mask2;
210
211
    vec_init_mask_true(int_mask);
    vec_init_mask_true(int_mask2);
James Willis's avatar
James Willis committed
212
213

    /* Perform interactions. */
James Willis's avatar
James Willis committed
214
215
216
217
218
219
    for (int pjd = 0; pjd < icount_align; pjd += (NUM_VEC_PROC * VEC_SIZE)) {
      runner_iact_nonsym_2_vec_density(
          &int_cache->r2q[pjd], &int_cache->dxq[pjd], &int_cache->dyq[pjd],
          &int_cache->dzq[pjd], v_hi_inv, v_vix, v_viy, v_viz,
          &int_cache->vxq[pjd], &int_cache->vyq[pjd], &int_cache->vzq[pjd],
          &int_cache->mq[pjd], rhoSum, rho_dhSum, wcountSum, wcount_dhSum,
220
          div_vSum, curlvxSum, curlvySum, curlvzSum, int_mask, int_mask2, 0);
221
    }
James Willis's avatar
James Willis committed
222
223

    /* Reset interaction count. */
224
225
226
    *icount = 0;
  }
}
227

228
/**
229
230
 * @brief Populates the arrays max_index_i and max_index_j with the maximum
 * indices of
James Willis's avatar
James Willis committed
231
232
233
 * particles into their neighbouring cells. Also finds the first pi that
 * interacts with any particle in cj and the last pj that interacts with any
 * particle in ci.
234
 *
James Willis's avatar
James Willis committed
235
236
237
238
239
240
 * @param ci #cell pointer to ci
 * @param cj #cell pointer to cj
 * @param sort_i #entry array for particle distance in ci
 * @param sort_j #entry array for particle distance in cj
 * @param dx_max maximum particle movement allowed in cell
 * @param rshift cutoff shift
241
242
243
244
 * @param hi_max Maximal smoothing length in cell ci
 * @param hj_max Maximal smoothing length in cell cj
 * @param di_max Maximal position on the axis that can interact in cell ci
 * @param dj_min Minimal position on the axis that can interact in cell ci
245
246
 * @param max_index_i array to hold the maximum distances of pi particles into
 * cell
James Willis's avatar
James Willis committed
247
 * cj
248
249
 * @param max_index_j array to hold the maximum distances of pj particles into
 * cell
James Willis's avatar
James Willis committed
250
 * cj
James Willis's avatar
James Willis committed
251
252
 * @param init_pi first pi to interact with a pj particle
 * @param init_pj last pj to interact with a pi particle
253
 * @param e The #engine.
James Willis's avatar
James Willis committed
254
 */
255
__attribute__((always_inline)) INLINE static void populate_max_index_no_cache(
James Willis's avatar
James Willis committed
256
257
    const struct cell *ci, const struct cell *cj,
    const struct entry *restrict sort_i, const struct entry *restrict sort_j,
258
259
    const float dx_max, const float rshift, const double hi_max,
    const double hj_max, const double di_max, const double dj_min,
260
    int *max_index_i, int *max_index_j, int *init_pi, int *init_pj,
261
    const struct engine *e) {
262

263
264
  const struct part *restrict parts_i = ci->parts;
  const struct part *restrict parts_j = cj->parts;
265
266

  int first_pi = 0, last_pj = cj->count - 1;
267
  int temp;
268

James Willis's avatar
James Willis committed
269
270
  /* Find the leftmost active particle in cell i that interacts with any
   * particle in cell j. */
271
  first_pi = ci->count;
272
  int active_id = first_pi - 1;
273
  while (first_pi > 0 && sort_i[first_pi - 1].d + dx_max + hi_max > dj_min) {
274
    first_pi--;
275
276
277
    /* Store the index of the particle if it is active. */
    if (part_is_active(&parts_i[sort_i[first_pi].i], e)) active_id = first_pi;
  }
James Willis's avatar
James Willis committed
278

279
280
  /* Set the first active pi in range of any particle in cell j. */
  first_pi = active_id;
281

282
  /* Find the maximum index into cell j for each particle in range in cell i. */
James Willis's avatar
James Willis committed
283
  if (first_pi < ci->count) {
284

285
286
    /* Start from the first particle in cell j. */
    temp = 0;
287

288
    const struct part *pi = &parts_i[sort_i[first_pi].i];
289

290
    /* Loop through particles in cell j until they are not in range of pi. */
James Willis's avatar
James Willis committed
291
292
293
    while (temp <= cj->count &&
           (sort_i[first_pi].d + (pi->h * kernel_gamma + dx_max - rshift) >
            sort_j[temp].d))
294
      temp++;
295

296
    max_index_i[first_pi] = temp;
297

298
    /* Populate max_index_i for remaining particles that are within range. */
James Willis's avatar
James Willis committed
299
    for (int i = first_pi + 1; i < ci->count; i++) {
300
      temp = max_index_i[i - 1];
301
      pi = &parts_i[sort_i[i].i];
302

James Willis's avatar
James Willis committed
303
304
305
      while (temp <= cj->count &&
             (sort_i[i].d + (pi->h * kernel_gamma + dx_max - rshift) >
              sort_j[temp].d))
306
        temp++;
307

308
      max_index_i[i] = temp;
309
    }
James Willis's avatar
James Willis committed
310
  } else {
311
312
    /* Make sure that max index is set to first particle in cj.*/
    max_index_i[ci->count - 1] = 0;
313
314
  }

James Willis's avatar
James Willis committed
315
316
  /* Find the rightmost active particle in cell j that interacts with any
   * particle in cell i. */
317
  last_pj = -1;
318
  active_id = last_pj;
James Willis's avatar
James Willis committed
319
320
  while (last_pj < cj->count &&
         sort_j[last_pj + 1].d - hj_max - dx_max < di_max) {
321
    last_pj++;
322
    /* Store the index of the particle if it is active. */
323
    if (part_is_active(&parts_j[sort_j[last_pj].i], e)) active_id = last_pj;
324
  }
James Willis's avatar
James Willis committed
325

326
  /* Set the last active pj in range of any particle in cell i. */
327
  last_pj = active_id;
Matthieu Schaller's avatar
Matthieu Schaller committed
328

329
  /* Find the maximum index into cell i for each particle in range in cell j. */
330
  if (last_pj > 0) {
Matthieu Schaller's avatar
Matthieu Schaller committed
331

332
333
    /* Start from the last particle in cell i. */
    temp = ci->count - 1;
334

335
    const struct part *pj = &parts_j[sort_j[last_pj].i];
336

337
    /* Loop through particles in cell i until they are not in range of pj. */
James Willis's avatar
James Willis committed
338
339
340
    while (temp > 0 &&
           sort_j[last_pj].d - dx_max - (pj->h * kernel_gamma) <
               sort_i[temp].d - rshift)
341
      temp--;
342

343
    max_index_j[last_pj] = temp;
344

345
    /* Populate max_index_j for remaining particles that are within range. */
James Willis's avatar
James Willis committed
346
    for (int i = last_pj - 1; i >= 0; i--) {
347
      temp = max_index_j[i + 1];
348
      pj = &parts_j[sort_j[i].i];
349

James Willis's avatar
James Willis committed
350
351
352
      while (temp > 0 &&
             sort_j[i].d - dx_max - (pj->h * kernel_gamma) <
                 sort_i[temp].d - rshift)
353
        temp--;
354

355
356
      max_index_j[i] = temp;
    }
James Willis's avatar
James Willis committed
357
  } else {
358
    /* Make sure that max index is set to last particle in ci.*/
James Willis's avatar
James Willis committed
359
    max_index_j[0] = ci->count - 1;
360
361
  }

James Willis's avatar
James Willis committed
362
363
  *init_pi = first_pi;
  *init_pj = last_pj;
364
}
James Willis's avatar
James Willis committed
365
#endif /* WITH_VECTORIZATION */
366
367

/**
James Willis's avatar
James Willis committed
368
369
 * @brief Compute the cell self-interaction (non-symmetric) using vector
 * intrinsics with one particle pi at a time.
370
371
372
373
 *
 * @param r The #runner.
 * @param c The #cell.
 */
James Willis's avatar
James Willis committed
374
375
__attribute__((always_inline)) INLINE void runner_doself1_density_vec(
    struct runner *r, struct cell *restrict c) {
376
377

#ifdef WITH_VECTORIZATION
378
  const struct engine *e = r->e;
379
380
381
382
383
384
  struct part *restrict pi;
  int count_align;
  int num_vec_proc = NUM_VEC_PROC;

  struct part *restrict parts = c->parts;
  const int count = c->count;
James Willis's avatar
James Willis committed
385

386
387
  vector v_hi, v_vix, v_viy, v_viz, v_hig2, v_r2;

James Willis's avatar
James Willis committed
388
  TIMER_TIC
389

390
391
  if (!cell_is_active(c, e)) return;

392
  if (!cell_are_part_drifted(c, e)) error("Interacting undrifted cell.");
393

James Willis's avatar
James Willis committed
394
  /* Get the particle cache from the runner and re-allocate
395
   * the cache if it is not big enough for the cell. */
396
  struct cache *restrict cell_cache = &r->ci_cache;
James Willis's avatar
James Willis committed
397
398
399

  if (cell_cache->count < count) {
    cache_init(cell_cache, count);
400
401
  }

James Willis's avatar
James Willis committed
402
  /* Read the particles from the cell and store them locally in the cache. */
James Willis's avatar
James Willis committed
403
  cache_read_particles(c, cell_cache);
404
405
406
407

  /* Create secondary cache to store particle interactions. */
  struct c2_cache int_cache;
  int icount = 0, icount_align = 0;
408
409
410
411
412
413
414
415

  /* Loop over the particles in the cell. */
  for (int pid = 0; pid < count; pid++) {

    /* Get a pointer to the ith particle. */
    pi = &parts[pid];

    /* Is the ith particle active? */
416
    if (!part_is_active(pi, e)) continue;
417
418
419
420
421

    vector pix, piy, piz;

    const float hi = cell_cache->h[pid];

James Willis's avatar
James Willis committed
422
    /* Fill particle pi vectors. */
423
424
425
426
427
428
429
430
431
432
433
    pix.v = vec_set1(cell_cache->x[pid]);
    piy.v = vec_set1(cell_cache->y[pid]);
    piz.v = vec_set1(cell_cache->z[pid]);
    v_hi.v = vec_set1(hi);
    v_vix.v = vec_set1(cell_cache->vx[pid]);
    v_viy.v = vec_set1(cell_cache->vy[pid]);
    v_viz.v = vec_set1(cell_cache->vz[pid]);

    const float hig2 = hi * hi * kernel_gamma2;
    v_hig2.v = vec_set1(hig2);

James Willis's avatar
James Willis committed
434
    /* Reset cumulative sums of update vectors. */
James Willis's avatar
James Willis committed
435
436
437
    vector rhoSum, rho_dhSum, wcountSum, wcount_dhSum, div_vSum, curlvxSum,
        curlvySum, curlvzSum;

James Willis's avatar
James Willis committed
438
    /* Get the inverse of hi. */
439
    vector v_hi_inv;
James Willis's avatar
James Willis committed
440

441
    v_hi_inv = vec_reciprocal(v_hi);
James Willis's avatar
James Willis committed
442

443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
    rhoSum.v = vec_setzero();
    rho_dhSum.v = vec_setzero();
    wcountSum.v = vec_setzero();
    wcount_dhSum.v = vec_setzero();
    div_vSum.v = vec_setzero();
    curlvxSum.v = vec_setzero();
    curlvySum.v = vec_setzero();
    curlvzSum.v = vec_setzero();

    /* Pad cache if there is a serial remainder. */
    count_align = count;
    int rem = count % (num_vec_proc * VEC_SIZE);
    if (rem != 0) {
      int pad = (num_vec_proc * VEC_SIZE) - rem;

      count_align += pad;
459
460
461
462
463
464
465
466

      /* Set positions to the same as particle pi so when the r2 > 0 mask is
       * applied these extra contributions are masked out.*/
      for (int i = count; i < count_align; i++) {
        cell_cache->x[i] = pix.f[0];
        cell_cache->y[i] = piy.f[0];
        cell_cache->z[i] = piz.f[0];
      }
467
468
469
470
471
    }

    vector pjx, pjy, pjz;
    vector pjx2, pjy2, pjz2;

James Willis's avatar
James Willis committed
472
473
    /* Find all of particle pi's interacions and store needed values in the
     * secondary cache.*/
474
475
476
477
478
479
    for (int pjd = 0; pjd < count_align; pjd += (num_vec_proc * VEC_SIZE)) {

      /* Load 2 sets of vectors from the particle cache. */
      pjx.v = vec_load(&cell_cache->x[pjd]);
      pjy.v = vec_load(&cell_cache->y[pjd]);
      pjz.v = vec_load(&cell_cache->z[pjd]);
480

481
482
483
      pjx2.v = vec_load(&cell_cache->x[pjd + VEC_SIZE]);
      pjy2.v = vec_load(&cell_cache->y[pjd + VEC_SIZE]);
      pjz2.v = vec_load(&cell_cache->z[pjd + VEC_SIZE]);
James Willis's avatar
James Willis committed
484

485
      /* Compute the pairwise distance. */
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
      vector v_dx, v_dy, v_dz;
      vector v_dx_2, v_dy_2, v_dz_2, v_r2_2;

      v_dx.v = vec_sub(pix.v, pjx.v);
      v_dx_2.v = vec_sub(pix.v, pjx2.v);
      v_dy.v = vec_sub(piy.v, pjy.v);
      v_dy_2.v = vec_sub(piy.v, pjy2.v);
      v_dz.v = vec_sub(piz.v, pjz.v);
      v_dz_2.v = vec_sub(piz.v, pjz2.v);

      v_r2.v = vec_mul(v_dx.v, v_dx.v);
      v_r2_2.v = vec_mul(v_dx_2.v, v_dx_2.v);
      v_r2.v = vec_fma(v_dy.v, v_dy.v, v_r2.v);
      v_r2_2.v = vec_fma(v_dy_2.v, v_dy_2.v, v_r2_2.v);
      v_r2.v = vec_fma(v_dz.v, v_dz.v, v_r2.v);
      v_r2_2.v = vec_fma(v_dz_2.v, v_dz_2.v, v_r2_2.v);
James Willis's avatar
James Willis committed
502

503
      /* Form a mask from r2 < hig2 and r2 > 0.*/
James Willis's avatar
James Willis committed
504
505
      mask_t v_doi_mask, v_doi_mask_self_check, v_doi_mask2,
          v_doi_mask2_self_check;
506
      int doi_mask, doi_mask_self_check, doi_mask2, doi_mask2_self_check;
507

James Willis's avatar
James Willis committed
508
      /* Form r2 > 0 mask and r2 < hig2 mask. */
509
      vec_create_mask(v_doi_mask_self_check, vec_cmp_gt(v_r2.v, vec_setzero()));
510
      vec_create_mask(v_doi_mask, vec_cmp_lt(v_r2.v, v_hig2.v));
511

James Willis's avatar
James Willis committed
512
      /* Form r2 > 0 mask and r2 < hig2 mask. */
James Willis's avatar
James Willis committed
513
514
      vec_create_mask(v_doi_mask2_self_check,
                      vec_cmp_gt(v_r2_2.v, vec_setzero()));
515
      vec_create_mask(v_doi_mask2, vec_cmp_lt(v_r2_2.v, v_hig2.v));
516

517
518
519
520
521
522
      /* Form integer masks. */
      doi_mask_self_check = vec_form_int_mask(v_doi_mask_self_check);
      doi_mask = vec_form_int_mask(v_doi_mask);

      doi_mask2_self_check = vec_form_int_mask(v_doi_mask2_self_check);
      doi_mask2 = vec_form_int_mask(v_doi_mask2);
James Willis's avatar
James Willis committed
523

524
525
526
      /* Combine the two masks. */
      doi_mask = doi_mask & doi_mask_self_check;
      doi_mask2 = doi_mask2 & doi_mask2_self_check;
527

James Willis's avatar
James Willis committed
528
529
      /* If there are any interactions left pack interaction values into c2
       * cache. */
530
      if (doi_mask) {
531
        storeInteractions(doi_mask, pjd, &v_r2, &v_dx, &v_dy, &v_dz,
James Willis's avatar
James Willis committed
532
533
534
535
536
537
                          cell_cache, &int_cache, &icount, &rhoSum, &rho_dhSum,
                          &wcountSum, &wcount_dhSum, &div_vSum, &curlvxSum,
                          &curlvySum, &curlvzSum, v_hi_inv, v_vix, v_viy,
                          v_viz);
      }
      if (doi_mask2) {
538
539
        storeInteractions(doi_mask2, pjd + VEC_SIZE, &v_r2_2, &v_dx_2,
                          &v_dy_2, &v_dz_2, cell_cache, &int_cache,
James Willis's avatar
James Willis committed
540
541
542
                          &icount, &rhoSum, &rho_dhSum, &wcountSum,
                          &wcount_dhSum, &div_vSum, &curlvxSum, &curlvySum,
                          &curlvzSum, v_hi_inv, v_vix, v_viy, v_viz);
543
544
545
      }
    }

James Willis's avatar
James Willis committed
546
    /* Perform padded vector remainder interactions if any are present. */
Matthieu Schaller's avatar
Matthieu Schaller committed
547
548
549
    calcRemInteractions(&int_cache, icount, &rhoSum, &rho_dhSum, &wcountSum,
                        &wcount_dhSum, &div_vSum, &curlvxSum, &curlvySum,
                        &curlvzSum, v_hi_inv, v_vix, v_viy, v_viz,
James Willis's avatar
James Willis committed
550
551
552
553
                        &icount_align);

    /* Initialise masks to true in case remainder interactions have been
     * performed. */
554
    mask_t int_mask, int_mask2;
555
556
    vec_init_mask_true(int_mask);
    vec_init_mask_true(int_mask2);
557
558

    /* Perform interaction with 2 vectors. */
James Willis's avatar
James Willis committed
559
560
561
562
563
564
    for (int pjd = 0; pjd < icount_align; pjd += (num_vec_proc * VEC_SIZE)) {
      runner_iact_nonsym_2_vec_density(
          &int_cache.r2q[pjd], &int_cache.dxq[pjd], &int_cache.dyq[pjd],
          &int_cache.dzq[pjd], v_hi_inv, v_vix, v_viy, v_viz,
          &int_cache.vxq[pjd], &int_cache.vyq[pjd], &int_cache.vzq[pjd],
          &int_cache.mq[pjd], &rhoSum, &rho_dhSum, &wcountSum, &wcount_dhSum,
James Willis's avatar
James Willis committed
565
566
          &div_vSum, &curlvxSum, &curlvySum, &curlvzSum, int_mask, int_mask2,
          0);
567
568
    }

James Willis's avatar
James Willis committed
569
570
571
572
573
574
575
576
577
578
    /* Perform horizontal adds on vector sums and store result in particle pi.
     */
    VEC_HADD(rhoSum, pi->rho);
    VEC_HADD(rho_dhSum, pi->density.rho_dh);
    VEC_HADD(wcountSum, pi->density.wcount);
    VEC_HADD(wcount_dhSum, pi->density.wcount_dh);
    VEC_HADD(div_vSum, pi->density.div_v);
    VEC_HADD(curlvxSum, pi->density.rot_v[0]);
    VEC_HADD(curlvySum, pi->density.rot_v[1]);
    VEC_HADD(curlvzSum, pi->density.rot_v[2]);
579
580
581
582
583

    /* Reset interaction count. */
    icount = 0;
  } /* loop over all particles. */

James Willis's avatar
James Willis committed
584
  TIMER_TOC(timer_doself_density);
585
#endif /* WITH_VECTORIZATION */
586
587
}

588
/**
James Willis's avatar
James Willis committed
589
 * @brief Compute the force cell self-interaction (non-symmetric) using vector
590
591
592
593
594
595
596
597
598
599
600
601
 * intrinsics with one particle pi at a time.
 *
 * @param r The #runner.
 * @param c The #cell.
 */
__attribute__((always_inline)) INLINE void runner_doself2_force_vec(
    struct runner *r, struct cell *restrict c) {

#ifdef WITH_VECTORIZATION
  const struct engine *e = r->e;
  struct part *restrict pi;
  int count_align;
James Willis's avatar
James Willis committed
602
  const int num_vec_proc = 1;
603
604
605
606
607
608
609

  struct part *restrict parts = c->parts;
  const int count = c->count;

  vector v_hi, v_vix, v_viy, v_viz, v_hig2, v_r2;
  vector v_rhoi, v_grad_hi, v_pOrhoi2, v_balsara_i, v_ci;

610
  TIMER_TIC
611
612
613

  if (!cell_is_active(c, e)) return;

614
  if (!cell_are_part_drifted(c, e)) error("Interacting undrifted cell.");
615
616
617
618
619
620
621
622
623
624

  /* Get the particle cache from the runner and re-allocate
   * the cache if it is not big enough for the cell. */
  struct cache *restrict cell_cache = &r->ci_cache;

  if (cell_cache->count < count) {
    cache_init(cell_cache, count);
  }

  /* Read the particles from the cell and store them locally in the cache. */
625
  cache_read_force_particles(c, cell_cache);
626

James Willis's avatar
James Willis committed
627
#ifdef SWIFT_DEBUG_CHECKS
James Willis's avatar
James Willis committed
628
  for (int i = 0; i < count; i++) {
James Willis's avatar
James Willis committed
629
630
631
632
633
    pi = &c->parts[i];
    /* Check that particles have been drifted to the current time */
    if (pi->ti_drift != e->ti_current)
      error("Particle pi not drifted to current time");
  }
James Willis's avatar
James Willis committed
634
}
James Willis's avatar
James Willis committed
635
636
#endif

637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
/* Loop over the particles in the cell. */
for (int pid = 0; pid < count; pid++) {

  /* Get a pointer to the ith particle. */
  pi = &parts[pid];

  /* Is the ith particle active? */
  if (!part_is_active(pi, e)) continue;

  vector pix, piy, piz;

  const float hi = cell_cache->h[pid];

  /* Fill particle pi vectors. */
  pix.v = vec_set1(cell_cache->x[pid]);
  piy.v = vec_set1(cell_cache->y[pid]);
  piz.v = vec_set1(cell_cache->z[pid]);
  v_hi.v = vec_set1(hi);
  v_vix.v = vec_set1(cell_cache->vx[pid]);
  v_viy.v = vec_set1(cell_cache->vy[pid]);
  v_viz.v = vec_set1(cell_cache->vz[pid]);

  v_rhoi.v = vec_set1(cell_cache->rho[pid]);
  v_grad_hi.v = vec_set1(cell_cache->grad_h[pid]);
  v_pOrhoi2.v = vec_set1(cell_cache->pOrho2[pid]);
  v_balsara_i.v = vec_set1(cell_cache->balsara[pid]);
  v_ci.v = vec_set1(cell_cache->soundspeed[pid]);

  const float hig2 = hi * hi * kernel_gamma2;
  v_hig2.v = vec_set1(hig2);

  /* Reset cumulative sums of update vectors. */
  vector a_hydro_xSum, a_hydro_ySum, a_hydro_zSum, h_dtSum, v_sigSum,
      entropy_dtSum;

  /* Get the inverse of hi. */
  vector v_hi_inv;

  v_hi_inv = vec_reciprocal(v_hi);

  a_hydro_xSum.v = vec_setzero();
  a_hydro_ySum.v = vec_setzero();
  a_hydro_zSum.v = vec_setzero();
  h_dtSum.v = vec_setzero();
  v_sigSum.v = vec_set1(pi->force.v_sig);
  entropy_dtSum.v = vec_setzero();

  /* Pad cache if there is a serial remainder. */
  count_align = count;
  int rem = count % (num_vec_proc * VEC_SIZE);
  if (rem != 0) {
    int pad = (num_vec_proc * VEC_SIZE) - rem;

    count_align += pad;

    /* Set positions to the same as particle pi so when the r2 > 0 mask is
     * applied these extra contributions are masked out.*/
    for (int i = count; i < count_align; i++) {
      cell_cache->x[i] = pix.f[0];
      cell_cache->y[i] = piy.f[0];
      cell_cache->z[i] = piz.f[0];
      cell_cache->h[i] = 1.f;
    }
  }

  vector pjx, pjy, pjz, hj, hjg2;

  /* Find all of particle pi's interacions and store needed values in the
   * secondary cache.*/
  for (int pjd = 0; pjd < count_align; pjd += (num_vec_proc * VEC_SIZE)) {

708
    /* Load 1 set of vectors from the particle cache. */
709
710
711
712
713
714
715
    pjx.v = vec_load(&cell_cache->x[pjd]);
    pjy.v = vec_load(&cell_cache->y[pjd]);
    pjz.v = vec_load(&cell_cache->z[pjd]);
    hj.v = vec_load(&cell_cache->h[pjd]);
    hjg2.v = vec_mul(vec_mul(hj.v, hj.v), kernel_gamma2_vec.v);

    /* Compute the pairwise distance. */
716
    vector v_dx, v_dy, v_dz;
717

718
719
720
    v_dx.v = vec_sub(pix.v, pjx.v);
    v_dy.v = vec_sub(piy.v, pjy.v);
    v_dz.v = vec_sub(piz.v, pjz.v);
721

722
723
724
    v_r2.v = vec_mul(v_dx.v, v_dx.v);
    v_r2.v = vec_fma(v_dy.v, v_dy.v, v_r2.v);
    v_r2.v = vec_fma(v_dz.v, v_dz.v, v_r2.v);
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745

    /* Form r2 > 0 mask, r2 < hig2 mask and r2 < hjg2 mask. */
    mask_t v_doi_mask, v_doi_mask_self_check;
    int doi_mask;

    /* Form r2 > 0 mask.*/
    vec_create_mask(v_doi_mask_self_check, vec_cmp_gt(v_r2.v, vec_setzero()));

    /* Form a mask from r2 < hig2 mask and r2 < hjg2 mask. */
    vector v_h2;
    v_h2.v = vec_fmax(v_hig2.v, hjg2.v);
    vec_create_mask(v_doi_mask, vec_cmp_lt(v_r2.v, v_h2.v));

    /* Combine all 3 masks and form integer mask. */
    v_doi_mask.v = vec_and(v_doi_mask.v, v_doi_mask_self_check.v);
    doi_mask = vec_form_int_mask(v_doi_mask);

    /* If there are any interactions left pack interaction values into c2
     * cache. */
    if (doi_mask) {
      vector v_hj, v_hj_inv;
746
      v_hj.v = vec_load(&cell_cache->h[pjd]);
747
748
      v_hj_inv = vec_reciprocal(v_hj);

749
750
751
      /* To stop floating point exceptions for when particle separations are 0. */
      v_r2.v = vec_add(v_r2.v, vec_set1(FLT_MIN));

752
      runner_iact_nonsym_1_vec_force(
753
              &v_r2, &v_dx, &v_dy, &v_dz, v_vix, v_viy, v_viz, 
754
              v_rhoi, v_grad_hi, v_pOrhoi2, v_balsara_i, v_ci,
755
756
757
              &cell_cache->vx[pjd], &cell_cache->vy[pjd],
              &cell_cache->vz[pjd], &cell_cache->rho[pjd], &cell_cache->grad_h[pjd],
              &cell_cache->pOrho2[pjd], &cell_cache->balsara[pjd], &cell_cache->soundspeed[pjd], &cell_cache->m[pjd], v_hi_inv, v_hj_inv, &a_hydro_xSum, &a_hydro_ySum, &a_hydro_zSum,
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
          &h_dtSum, &v_sigSum, &entropy_dtSum, v_doi_mask);

    }

  } /* Loop over all other particles. */

  VEC_HADD(a_hydro_xSum, pi->a_hydro[0]);
  VEC_HADD(a_hydro_ySum, pi->a_hydro[1]);
  VEC_HADD(a_hydro_zSum, pi->a_hydro[2]);
  VEC_HADD(h_dtSum, pi->force.h_dt);
  VEC_HMAX(v_sigSum, pi->force.v_sig);
  VEC_HADD(entropy_dtSum, pi->entropy_dt);

} /* loop over all particles. */

James Willis's avatar
James Willis committed
773
TIMER_TOC(timer_doself_force);
774
775
776
#endif /* WITH_VECTORIZATION */
}

777
/**
James Willis's avatar
James Willis committed
778
779
 * @brief Compute the density interactions between a cell pair (non-symmetric)
 * using vector intrinsics.
780
781
782
783
 *
 * @param r The #runner.
 * @param ci The first #cell.
 * @param cj The second #cell.
784
785
 * @param sid The direction of the pair
 * @param shift The shift vector to apply to the particles in ci.
786
 */
James Willis's avatar
James Willis committed
787
void runner_dopair1_density_vec(struct runner *r, struct cell *ci,
788
789
                                struct cell *cj, const int sid,
                                const double *shift) {
790
791
792
793

#ifdef WITH_VECTORIZATION
  const struct engine *restrict e = r->e;

James Willis's avatar
James Willis committed
794
  vector v_hi, v_vix, v_viy, v_viz, v_hig2;
795
796
797

  TIMER_TIC;

798
799
800
801
802
  /* Get the cutoff shift. */
  double rshift = 0.0;
  for (int k = 0; k < 3; k++) rshift += shift[k] * runner_shift[sid][k];

  /* Pick-out the sorted lists. */
Peter W. Draper's avatar
Peter W. Draper committed
803
804
  const struct entry *restrict sort_i = ci->sort[sid];
  const struct entry *restrict sort_j = cj->sort[sid];
805

806
807
808
809
810
811
812
813
814
#ifdef SWIFT_DEBUG_CHECKS
  /* Check that the dx_max_sort values in the cell are indeed an upper
     bound on particle movement. */
  for (int pid = 0; pid < ci->count; pid++) {
    const struct part *p = &ci->parts[sort_i[pid].i];
    const float d = p->x[0] * runner_shift[sid][0] +
                    p->x[1] * runner_shift[sid][1] +
                    p->x[2] * runner_shift[sid][2];
    if (fabsf(d - sort_i[pid].d) - ci->dx_max_sort >
815
        1.0e-4 * max(fabsf(d), ci->dx_max_sort_old))
816
817
818
819
820
821
      error(
          "particle shift diff exceeds dx_max_sort in cell ci. ci->nodeID=%d "
          "cj->nodeID=%d d=%e sort_i[pid].d=%e ci->dx_max_sort=%e "
          "ci->dx_max_sort_old=%e",
          ci->nodeID, cj->nodeID, d, sort_i[pid].d, ci->dx_max_sort,
          ci->dx_max_sort_old);
822
823
824
825
826
827
828
  }
  for (int pjd = 0; pjd < cj->count; pjd++) {
    const struct part *p = &cj->parts[sort_j[pjd].i];
    const float d = p->x[0] * runner_shift[sid][0] +
                    p->x[1] * runner_shift[sid][1] +
                    p->x[2] * runner_shift[sid][2];
    if (fabsf(d - sort_j[pjd].d) - cj->dx_max_sort >
829
        1.0e-4 * max(fabsf(d), cj->dx_max_sort_old))
830
831
832
833
834
835
      error(
          "particle shift diff exceeds dx_max_sort in cell cj. cj->nodeID=%d "
          "ci->nodeID=%d d=%e sort_j[pjd].d=%e cj->dx_max_sort=%e "
          "cj->dx_max_sort_old=%e",
          cj->nodeID, ci->nodeID, d, sort_j[pjd].d, cj->dx_max_sort,
          cj->dx_max_sort_old);
836
837
838
  }
#endif /* SWIFT_DEBUG_CHECKS */

839
840
841
842
843
844
845
846
847
  /* Get some other useful values. */
  const int count_i = ci->count;
  const int count_j = cj->count;
  const double hi_max = ci->h_max * kernel_gamma - rshift;
  const double hj_max = cj->h_max * kernel_gamma;
  struct part *restrict parts_i = ci->parts;
  struct part *restrict parts_j = cj->parts;
  const double di_max = sort_i[count_i - 1].d - rshift;
  const double dj_min = sort_j[0].d;
848
  const float dx_max = (ci->dx_max_sort + cj->dx_max_sort);
849
850

  /* Check if any particles are active and return if there are not. */
Matthieu Schaller's avatar
Matthieu Schaller committed
851
852
853
  int numActive = 0;
  for (int pid = count_i - 1;
       pid >= 0 && sort_i[pid].d + hi_max + dx_max > dj_min; pid--) {
854
855
856
857
    struct part *restrict pi = &parts_i[sort_i[pid].i];
    if (part_is_active(pi, e)) {
      numActive++;
      break;
Matthieu Schaller's avatar
Matthieu Schaller committed
858
    }
859
  }
860

Matthieu Schaller's avatar
Matthieu Schaller committed
861
  if (!numActive) {
862
    for (int pjd = 0; pjd < count_j && sort_j[pjd].d - hj_max - dx_max < di_max;
Matthieu Schaller's avatar
Matthieu Schaller committed
863
         pjd++) {
864
865
      struct part *restrict pj = &parts_j[sort_j[pjd].i];
      if (part_is_active(pj, e)) {
866
867
        numActive++;
        break;
Matthieu Schaller's avatar
Matthieu Schaller committed
868
869
      }
    }
870
  }
871

Matthieu Schaller's avatar
Matthieu Schaller committed
872
  if (numActive == 0) return;
873

874
875
876
877
  /* Get both particle caches from the runner and re-allocate
   * them if they are not big enough for the cells. */
  struct cache *restrict ci_cache = &r->ci_cache;
  struct cache *restrict cj_cache = &r->cj_cache;
878

879
880
881
882
883
884
  if (ci_cache->count < count_i) {
    cache_init(ci_cache, count_i);
  }
  if (cj_cache->count < count_j) {
    cache_init(cj_cache, count_j);
  }
885

886
  int first_pi, last_pj;
887
888
  int *max_index_i __attribute__((aligned(sizeof(int) * VEC_SIZE)));
  int *max_index_j __attribute__((aligned(sizeof(int) * VEC_SIZE)));
889

890
891
  max_index_i = r->ci_cache.max_index;
  max_index_j = r->cj_cache.max_index;
892

893
894
  /* Find particles maximum index into cj, max_index_i[] and ci, max_index_j[].
   */
895
896
  /* Also find the first pi that interacts with any particle in cj and the last
   * pj that interacts with any particle in ci. */
897
  populate_max_index_no_cache(ci, cj, sort_i, sort_j, dx_max, rshift, hi_max,
898
899
                              hj_max, di_max, dj_min, max_index_i, max_index_j,
                              &first_pi, &last_pj, e);
900

901
902
903
904
  /* Limits of the outer loops. */
  int first_pi_loop = first_pi;
  int last_pj_loop = last_pj;

905
906
  /* Take the max/min of both values calculated to work out how many particles
   * to read into the cache. */
907
908
  last_pj = max(last_pj, max_index_i[count_i - 1]);
  first_pi = min(first_pi, max_index_j[0]);
909

910
911
912
913
  /* Read the needed particles into the two caches. */
  int first_pi_align = first_pi;
  int last_pj_align = last_pj;
  cache_read_two_partial_cells_sorted(ci, cj, ci_cache, cj_cache, sort_i,
Matthieu Schaller's avatar
Matthieu Schaller committed
914
915
                                      sort_j, shift, &first_pi_align,
                                      &last_pj_align, 1);
916

917
918
  /* Get the number of particles read into the ci cache. */
  int ci_cache_count = count_i - first_pi_align;
919

920
  if (cell_is_active(ci, e)) {
921

James Willis's avatar
James Willis committed
922
    /* Loop over the parts in ci until nothing is within range in cj. */
923
    for (int pid = count_i - 1; pid >= first_pi_loop; pid--) {
924

925
926
927
      /* Get a hold of the ith part in ci. */
      struct part *restrict pi = &parts_i[sort_i[pid].i];
      if (!part_is_active(pi, e)) continue;
928

929
930
      /* Set the cache index. */
      int ci_cache_idx = pid - first_pi_align;
931

James Willis's avatar
James Willis committed
932
      /* Skip this particle if no particle in cj is within range of it. */
933
      const float hi = ci_cache->h[ci_cache_idx];
934
935
      const double di_test =
          sort_i[pid].d + hi * kernel_gamma + dx_max - rshift;
936
937
      if (di_test < dj_min) continue;

938
      /* Determine the exit iteration of the interaction loop. */
939
      int exit_iteration = max_index_i[pid];
940

941
      const float hig2 = hi * hi * kernel_gamma2;
942

943
      vector pix, piy, piz;
944

945
946
947
948
949
950
951
952
      /* Fill particle pi vectors. */
      pix.v = vec_set1(ci_cache->x[ci_cache_idx]);
      piy.v = vec_set1(ci_cache->y[ci_cache_idx]);
      piz.v = vec_set1(ci_cache->z[ci_cache_idx]);
      v_hi.v = vec_set1(hi);
      v_vix.v = vec_set1(ci_cache->vx[ci_cache_idx]);
      v_viy.v = vec_set1(ci_cache->vy[ci_cache_idx]);
      v_viz.v = vec_set1(ci_cache->vz[ci_cache_idx]);
953

954
      v_hig2.v = vec_set1(hig2);
955

956
957
      /* Reset cumulative sums of update vectors. */
      vector rhoSum, rho_dhSum, wcountSum, wcount_dhSum, div_vSum, curlvxSum,
Matthieu Schaller's avatar
Matthieu Schaller committed
958
          curlvySum, curlvzSum;
959

960
961
      /* Get the inverse of hi. */
      vector v_hi_inv;
962

963
      v_hi_inv = vec_reciprocal(v_hi);
964

965
966
967
968
969
970
971
972
      rhoSum.v = vec_setzero();
      rho_dhSum.v = vec_setzero();
      wcountSum.v = vec_setzero();
      wcount_dhSum.v = vec_setzero();
      div_vSum.v = vec_setzero();
      curlvxSum.v = vec_setzero();
      curlvySum.v = vec_setzero();
      curlvzSum.v = vec_setzero();
973

974
975
976
977
978
      /* Pad the exit iteration if there is a serial remainder. */
      int exit_iteration_align = exit_iteration;
      int rem = exit_iteration % VEC_SIZE;
      if (rem != 0) {
        int pad = VEC_SIZE - rem;
979

980
981
982
        if (exit_iteration_align + pad <= last_pj_align + 1)
          exit_iteration_align += pad;
      }
983

984
      vector pjx, pjy, pjz;
985

986
987
      /* Loop over the parts in cj. */
      for (int pjd = 0; pjd < exit_iteration_align; pjd += VEC_SIZE) {
988

989
990
        /* Get the cache index to the jth particle. */
        int cj_cache_idx = pjd;
991

992
        vector v_dx, v_dy, v_dz, v_r2;
993

994
#ifdef SWIFT_DEBUG_CHECKS
James Willis's avatar
James Willis committed
995
996
997
998
        if (cj_cache_idx % VEC_SIZE != 0 || cj_cache_idx < 0 ||
            cj_cache_idx + (VEC_SIZE - 1) > (last_pj_align + 1 + VEC_SIZE)) {
          error("Unaligned read!!! cj_cache_idx=%d, last_pj_align=%d",
                cj_cache_idx, last_pj_align);
999
1000
        }
#endif
1001

1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
        /* Load 2 sets of vectors from the particle cache. */
        pjx.v = vec_load(&cj_cache->x[cj_cache_idx]);
        pjy.v = vec_load(&cj_cache->y[cj_cache_idx]);
        pjz.v = vec_load(&cj_cache->z[cj_cache_idx]);

        /* Compute the pairwise distance. */
        v_dx.v = vec_sub(pix.v, pjx.v);
        v_dy.v = vec_sub(piy.v, pjy.v);
        v_dz.v = vec_sub(piz.v, pjz.v);

        v_r2.v = vec_mul(v_dx.v, v_dx.v);
        v_r2.v = vec_fma(v_dy.v, v_dy.v, v_r2.v);
        v_r2.v = vec_fma(v_dz.v, v_dz.v, v_r2.v);

1016
        mask_t v_doi_mask;