activation.cc 20.6 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 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
// Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "paddle/fluid/lite/arm/math/activation.h"
#include "paddle/fluid/lite/arm/math/funcs.h"

namespace paddle {
namespace lite {
namespace arm {
namespace math {

template <>
void act_relu<float>(const float* din, float* dout, int size, int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt = nums_per_thread >> 4;
  int neon_loop_remain = nums_per_thread - (neon_loop_cnt << 4);
  float32x4_t vzero = vdupq_n_f32(0.f);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    int cnt = neon_loop_cnt;
#ifdef __aarch64__
    for (int num = 0; num < neon_loop_cnt; ++num) {
      float32x4_t vr0 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr1 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr2 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr3 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      vr0 = vmaxq_f32(vr0, vzero);
      vr1 = vmaxq_f32(vr1, vzero);
      vr2 = vmaxq_f32(vr2, vzero);
      vr3 = vmaxq_f32(vr3, vzero);
      vst1q_f32(ptr_out_thread, vr0);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vr1);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vr2);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vr3);
      ptr_out_thread += 4;
    }

#else
    if (cnt > 0) {
      asm volatile(
          "1:                                     @ loop header\n"
          "vld1.32  {d0-d3}, [%[din]]!            @ load din 0\n"
          "vld1.32  {d4-d7}, [%[din]]!            @ load din 0\n"

          "vmax.f32 q8, q0, %q[vzero]             @ relu\n"
          "vmax.f32 q9, q1, %q[vzero]             @ relu\n"
          "vmax.f32 q10, q2, %q[vzero]            @ relu\n"
          "vmax.f32 q11, q3, %q[vzero]            @ relu\n"

          "vst1.32  {d16-d19}, [%[dout]]!         @ store result, add pointer\n"
          "vst1.32  {d20-d23}, [%[dout]]!         @ store result, add pointer\n"

          "subs %[cnt], #1                        @ loop count minus 1\n"
          "bne    1b                              @ jump to main loop start "
          "point\n"
          : [dout] "+r"(ptr_out_thread), [din] "+r"(ptr_in_thread),
            [cnt] "+r"(cnt)
          : [vzero] "w"(vzero)
          : "cc", "memory", "q0", "q1", "q2", "q3", "q8", "q9", "q10", "q11");
    }
#endif
    for (int j = 0; j < neon_loop_remain; ++j) {
      ptr_out_thread[0] = ptr_in_thread[0] > 0.f ? ptr_in_thread[0] : 0.f;
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* out_ptr_remain = dout + threads * nums_per_thread;
  const float* in_ptr_remain = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    out_ptr_remain[0] = in_ptr_remain[0] > 0.f ? in_ptr_remain[0] : 0.f;
    in_ptr_remain++;
    out_ptr_remain++;
  }
}

template <>
void act_relu_neg<float>(const float* din, float* dout, int size,
                         const float negative_slope, int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt = nums_per_thread >> 4;
  int neon_loop_remain = nums_per_thread - (neon_loop_cnt << 4);
  float32x4_t vzero = vdupq_n_f32(0.f);
  float32x4_t valpha = vdupq_n_f32(negative_slope);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    int cnt = neon_loop_cnt;
#ifdef __aarch64__
    for (int num = 0; num < neon_loop_cnt; ++num) {
      float32x4_t vr0 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr1 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr2 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr3 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;

      uint32x4_t vm0 = vcgeq_f32(vr0, vzero);
      uint32x4_t vm1 = vcgeq_f32(vr1, vzero);
      uint32x4_t vm2 = vcgeq_f32(vr2, vzero);
      uint32x4_t vm3 = vcgeq_f32(vr3, vzero);

      float32x4_t vn0 = vmulq_f32(vr0, valpha);
      float32x4_t vn1 = vmulq_f32(vr1, valpha);
      float32x4_t vn2 = vmulq_f32(vr2, valpha);
      float32x4_t vn3 = vmulq_f32(vr3, valpha);

      float32x4_t vo0 = vbslq_f32(vm0, vr0, vn0);
      float32x4_t vo1 = vbslq_f32(vm1, vr1, vn1);
      float32x4_t vo2 = vbslq_f32(vm2, vr2, vn2);
      float32x4_t vo3 = vbslq_f32(vm3, vr3, vn3);

      vst1q_f32(ptr_out_thread, vo0);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo1);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo2);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo3);
      ptr_out_thread += 4;
    }

#else
    if (cnt > 0) {
      asm volatile(
          "1:                                             @ loop header\n"
          "vld1.32  {d0-d3}, [%[din]]!            @ load din 0\n"
          "vld1.32  {d4-d7}, [%[din]]!            @ load din 0\n"

          "vcge.f32 q8, q0, %q[vzero]             @ get mask\n"
          "vcge.f32 q9, q1, %q[vzero]             @ get mask\n"
          "vcge.f32 q10, q2, %q[vzero]            @ get mask\n"
          "vcge.f32 q11, q3, %q[vzero]            @ get mask\n"

          "vmul.f32   q4, q0, %q[valpha]          @ get neg data\n"
          "vmul.f32   q5, q1, %q[valpha]          @ get neg data\n"
          "vmul.f32   q6, q2, %q[valpha]          @ get neg data\n"
          "vmul.f32   q7, q3, %q[valpha]          @ get neg data\n"

          "vbit   q4, q0, q8                      @ bitsel, insert q0 to q4, "
          "if q8 is 1\n"
          "vbit   q5, q1, q9                      @ bitsel, insert q1 to q5, "
          "if q9 is 1\n"
          "vbit   q6, q2, q10                     @ bitsel, insert q2 to q6, "
          "if q10 is 1\n"
          "vbit   q7, q3, q11                     @ bitsel, insert q3 to q7, "
          "if q11 is 1\n"

          "vst1.32  {d8-d11}, [%[dout]]!          @ store result, add pointer\n"
          "vst1.32  {d12-d15}, [%[dout]]!         @ store result, add pointer\n"

          "subs %[cnt], #1                        @ loop count minus 1\n"
          "bne    1b                              @ jump to main loop start "
          "point\n"
          : [dout] "+r"(ptr_out_thread), [din] "+r"(ptr_in_thread),
            [cnt] "+r"(cnt)
          : [vzero] "w"(vzero), [valpha] "w"(valpha)
          : "cc", "memory", "q0", "q1", "q2", "q3", "q4", "q5", "q6", "q7",
            "q8", "q9", "q10", "q11");
    }
#endif
    for (int j = 0; j < neon_loop_remain; ++j) {
      ptr_out_thread[0] = ptr_in_thread[0] > 0.f
                              ? ptr_in_thread[0]
                              : ptr_in_thread[0] * negative_slope;
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* out_ptr_remain = dout + threads * nums_per_thread;
  const float* in_ptr_remain = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    out_ptr_remain[0] = in_ptr_remain[0] > 0.f
                            ? in_ptr_remain[0]
                            : in_ptr_remain[0] * negative_slope;
    in_ptr_remain++;
    out_ptr_remain++;
  }
}

template <>
void act_clipped_relu<float>(const float* din, float* dout, int size,
                             const float coef, int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt = nums_per_thread >> 4;
  int neon_loop_remain = nums_per_thread - (neon_loop_cnt << 4);
  float32x4_t vzero = vdupq_n_f32(0.f);
  float32x4_t vclip = vdupq_n_f32(coef);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    int cnt = neon_loop_cnt;
#ifdef __aarch64__
    for (int num = 0; num < neon_loop_cnt; ++num) {
      float32x4_t vr0 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr1 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr2 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vr3 = vld1q_f32(ptr_in_thread);
      ptr_in_thread += 4;
      float32x4_t vt0 = vmaxq_f32(vr0, vzero);
      float32x4_t vt1 = vmaxq_f32(vr1, vzero);
      float32x4_t vt2 = vmaxq_f32(vr2, vzero);
      float32x4_t vt3 = vmaxq_f32(vr3, vzero);

      float32x4_t vo0 = vminq_f32(vt0, vclip);
      float32x4_t vo1 = vminq_f32(vt1, vclip);
      float32x4_t vo2 = vminq_f32(vt2, vclip);
      float32x4_t vo3 = vminq_f32(vt3, vclip);

      vst1q_f32(ptr_out_thread, vo0);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo1);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo2);
      ptr_out_thread += 4;
      vst1q_f32(ptr_out_thread, vo3);
      ptr_out_thread += 4;
    }
#else
    if (cnt > 0) {
      asm volatile(
          "1:                                     @ loop header\n"
          "vld1.32  {d0-d3}, [%[din]]!            @ load din 0\n"
          "vld1.32  {d4-d7}, [%[din]]!            @ load din 0\n"

          "vmax.f32 q8, q0, %q[vzero]             @ relu\n"
          "vmax.f32 q9, q1, %q[vzero]             @ relu\n"
          "vmax.f32 q10, q2, %q[vzero]            @ relu\n"
          "vmax.f32 q11, q3, %q[vzero]            @ relu\n"

          "vmin.f32 q4, q8, %q[vclip]             @ clip relu\n"
          "vmin.f32 q5, q9, %q[vclip]             @ clip relu\n"
          "vmin.f32 q6, q10, %q[vclip]            @ clip relu\n"
          "vmin.f32 q7, q11, %q[vclip]            @ clip relu\n"

          "vst1.32  {d8-d11}, [%[dout]]!          @ store result, add pointer\n"
          "vst1.32  {d12-d15}, [%[dout]]!         @ store result, add pointer\n"

          "subs %[cnt], #1                        @ loop count minus 1\n"
          "bne    1b                              @ jump to main loop start "
          "point\n"
          : [dout] "+r"(ptr_out_thread), [din] "+r"(ptr_in_thread),
            [cnt] "+r"(cnt)
          : [vzero] "w"(vzero), [vclip] "w"(vclip)
          : "cc", "memory", "q0", "q1", "q2", "q3", "q4", "q5", "q6", "q7",
            "q8", "q9", "q10", "q11");
    }
#endif
    for (int j = 0; j < neon_loop_remain; ++j) {
      ptr_out_thread[0] = ptr_in_thread[0] > 0.f ? ptr_in_thread[0] : 0.f;
      ptr_out_thread[0] = ptr_out_thread[0] < coef ? ptr_out_thread[0] : coef;
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* out_ptr_remain = dout + threads * nums_per_thread;
  const float* in_ptr_remain = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    out_ptr_remain[0] = in_ptr_remain[0] > 0.f ? in_ptr_remain[0] : 0.f;
    out_ptr_remain[0] = out_ptr_remain[0] < coef ? out_ptr_remain[0] : coef;
    in_ptr_remain++;
    out_ptr_remain++;
  }
}

template <>
void act_prelu<float>(const float* din, float* dout, int outer_size,
                      int channel_size, int inner_size, bool channel_shared,
                      float* channel_slope, int threads) {
  int stride_size = inner_size * channel_size;
  int cnt = inner_size >> 4;
  int remain = inner_size & 15;
  float32x4_t vzero = vdupq_n_f32(0.f);
  for (int n = 0; n < outer_size; n++) {
    const float* data_in_batch = din + n * stride_size;
    float* data_out_batch = dout + n * stride_size;
#pragma omp parallel for
    for (int c = 0; c < channel_size; c++) {
      const float* data_in_c = data_in_batch + c * inner_size;
      float* data_out_c = data_out_batch + c * inner_size;

      float slope = channel_shared ? channel_slope[0] : channel_slope[c];
      float32x4_t vslope = vdupq_n_f32(slope);
#ifdef __aarch64__
      for (int i = 0; i < cnt; ++i) {
        float32x4_t vr0 = vld1q_f32(data_in_c);
        float32x4_t vr1 = vld1q_f32(data_in_c + 4);
        float32x4_t vr2 = vld1q_f32(data_in_c + 8);
        float32x4_t vr3 = vld1q_f32(data_in_c + 12);
        uint32x4_t vm0 = vcltq_f32(vr0, vzero);    // vr0 <= vzero
        uint32x4_t vm1 = vcltq_f32(vr1, vzero);    // vr0 <= vzero
        uint32x4_t vm2 = vcltq_f32(vr2, vzero);    // vr0 <= vzero
        uint32x4_t vm3 = vcltq_f32(vr3, vzero);    // vr0 <= vzero
        float32x4_t vo0 = vmulq_f32(vr0, vslope);  // vr0 * vslope
        float32x4_t vo1 = vmulq_f32(vr1, vslope);  // vr0 * vslope
        float32x4_t vo2 = vmulq_f32(vr2, vslope);  // vr0 * vslope
        float32x4_t vo3 = vmulq_f32(vr3, vslope);  // vr0 * vslope
        float32x4_t vos0 = vbslq_f32(vm0, vo0, vr0);
        float32x4_t vos1 = vbslq_f32(vm1, vo1, vr1);
        float32x4_t vos2 = vbslq_f32(vm2, vo2, vr2);
        float32x4_t vos3 = vbslq_f32(vm3, vo3, vr3);
        vst1q_f32(data_out_c, vos0);
        vst1q_f32(data_out_c + 4, vos1);
        vst1q_f32(data_out_c + 8, vos2);
        vst1q_f32(data_out_c + 12, vos3);
        data_in_c += 16;
        data_out_c += 16;
      }
#else
      int cnt_loop = cnt;
      if (cnt_loop > 0) {
        asm volatile(
            "vld1.32    {d0-d3}, [%[ptr_in]]!                       @ load "
            "input to q0, q1\n"
            "pld [%[ptr_in]]                                @ preload\n"
            "pld [%[ptr_in], #64]                           @ preload\n"
            "pld [%[ptr_in], #128]                          @ preload\n"
            "pld [%[ptr_in], #192]                          @ preload\n"
            "1:                                             @main loop\n"
            "vld1.32    {d4-d7}, [%[ptr_in]]!               @ load input to "
            "q2, q3\n"
            "vclt.f32   q8, q0, %q[vzero]                   @vcle q0 <= vzero\n"
            "vclt.f32   q9, q1, %q[vzero]                   @vcle q1 <= vzero\n"
            "vmul.f32  q10, q0, %q[vslope]                  @vmul q0 * vslope\n"
            "vmul.f32  q11, q1, %q[vslope]                  @vmul q1 * vslope\n"

            "vclt.f32  q12, q2, %q[vzero]                   @vcle q2 <= vzero\n"
            "vclt.f32  q13, q3, %q[vzero]                   @vcle q3 <= vzero\n"
            "vmul.f32  q14, q2, %q[vslope]                  @vmul q2 * vslope\n"
            "vmul.f32  q15, q3, %q[vslope]                  @vmul q3 * vslope\n"

            "vbif.32    q10, q0, q8                         @vbit q10, q0, q8\n"
            "vbif.32    q11, q1, q9                         @vbit q11, q1, q9\n"
            "vbif.32    q14, q2, q12                        @vbit q14, q2, "
            "q12\n"
            "vbif.32    q15, q3, q13                        @vbit q15, q3, "
            "q13\n"

            "subs       %[cnt], #1                          @subs nn, 1\n"
            "vld1.32    {d0-d3}, [%[ptr_in]]!               @ load input to "
            "q0, q1\n"

            "vst1.f32   {d20-d23}, [%[dout]]!               @store data\n"
            "vst1.f32   {d28-d31}, [%[dout]]!               @store data\n"
            "bne        1b                                  @bne nn\n"
            "sub    %[ptr_in], #32                          @ ptr-32\n"
            : [ptr_in] "+r"(data_in_c), [cnt] "+r"(cnt_loop),
              [dout] "+r"(data_out_c)
            : [vzero] "w"(vzero), [vslope] "w"(vslope)
            : "cc", "memory", "q0", "q1", "q2", "q3", "q8", "q9", "q10", "q11",
              "q12", "q13", "q14", "q15");
      }
#endif  // __aarch64__
      for (int i = remain; i > 0; i--) {
        *(data_out_c++) =
            data_in_c[0] > 0.f ? data_in_c[0] : data_in_c[0] * slope;
        data_in_c++;
      }
    }
  }
}

template <>
void act_sigmoid(const float* din, float* dout, int size, int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt_dim4 = nums_per_thread >> 2;
  int neon_loop_remain_dim4 = nums_per_thread - (neon_loop_cnt_dim4 << 2);

  float32x4_t vzero = vdupq_n_f32(0.f);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    float32x4_t exp_vec = vdupq_n_f32(0.0f);
    float32x4_t recip = vdupq_n_f32(0.0f);
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    for (int k = 0; k < neon_loop_cnt_dim4; ++k) {
      exp_vec = exp_ps(vnegq_f32(vld1q_f32(ptr_in_thread)));
      exp_vec = vaddq_f32(exp_vec, vdupq_n_f32(1.0f));
      recip = vrecpeq_f32(exp_vec);
      recip = vmulq_f32(vrecpsq_f32(exp_vec, recip), recip);
      recip = vmulq_f32(vrecpsq_f32(exp_vec, recip), recip);
      vst1q_f32(ptr_out_thread, recip);
      ptr_out_thread += 4;
      ptr_in_thread += 4;
    }
    for (int j = 0; j < neon_loop_remain_dim4; ++j) {
      ptr_out_thread[0] = 1.f / (1 + expf(-ptr_in_thread[0]));
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* ptr_out = dout + threads * nums_per_thread;
  const float* ptr_in = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    ptr_out[0] = 1.f / (1 + expf(-ptr_in[0]));
    ptr_in++;
    ptr_out++;
  }
}

// tanh : (exp(x) - exp(-x)) / (exp(x) + exp(-x))
template <>
void act_tanh<float>(const float* din, float* dout, int size, int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt_dim4 = nums_per_thread >> 2;
  int neon_loop_remain_dim4 = nums_per_thread - (neon_loop_cnt_dim4 << 2);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    float32x4_t exp_plus_vec = vdupq_n_f32(0.0f);
    float32x4_t exp_minus_vec = vdupq_n_f32(0.0f);
    float32x4_t exp_sum_vec = vdupq_n_f32(0.0f);
    float32x4_t exp_diff_vec = vdupq_n_f32(0.0f);
    float32x4_t recip = vdupq_n_f32(0.0f);
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    for (int k = 0; k < neon_loop_cnt_dim4; ++k) {
      exp_plus_vec = exp_ps(vld1q_f32(ptr_in_thread));
      exp_minus_vec = exp_ps(vnegq_f32(vld1q_f32(ptr_in_thread)));
      exp_sum_vec = vaddq_f32(exp_plus_vec, exp_minus_vec);
      exp_diff_vec = vsubq_f32(exp_plus_vec, exp_minus_vec);
      recip = div_ps(exp_diff_vec, exp_sum_vec);
      vst1q_f32(ptr_out_thread, recip);
      ptr_out_thread += 4;
      ptr_in_thread += 4;
    }
    for (int j = 0; j < neon_loop_remain_dim4; ++j) {
      ptr_out_thread[0] = (expf(ptr_in_thread[0]) - expf(-ptr_in_thread[0])) /
                          (expf(ptr_in_thread[0]) + expf(-ptr_in_thread[0]));
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* ptr_out = dout + threads * nums_per_thread;
  const float* ptr_in = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    ptr_out[0] = (expf(ptr_in[0]) - expf(-ptr_in[0])) /
                 (expf(ptr_in[0]) + expf(-ptr_in[0]));
    ptr_in++;
    ptr_out++;
  }
}

// swish: x /(1 + exp(-(b * x)))
template <>
void act_swish<float>(const float* din, float* dout, int size, const float coef,
                      int threads) {
  int nums_per_thread = size / threads;
  int remain = size - threads * nums_per_thread;
  int neon_loop_cnt_dim4 = nums_per_thread >> 2;
  int neon_loop_remain_dim4 = nums_per_thread - (neon_loop_cnt_dim4 << 2);
  const float beta = coef;
  float32x4_t vbeta = vdupq_n_f32(beta);
  float32x4_t vone = vdupq_n_f32(1.f);
#pragma omp parallel for
  for (int i = 0; i < threads; ++i) {
    const float* ptr_in_thread = din + i * nums_per_thread;
    float* ptr_out_thread = dout + i * nums_per_thread;
    for (int k = 0; k < neon_loop_cnt_dim4; ++k) {
      float32x4_t va = vld1q_f32(ptr_in_thread);             // x
      float32x4_t vb = vnegq_f32(vld1q_f32(ptr_in_thread));  // -x
      float32x4_t vsum = vmulq_f32(vb, vbeta);
      vsum = exp_ps(vsum);
      float32x4_t vc = vaddq_f32(vone, vsum);
      float32x4_t vrst = div_ps(va, vc);
      vst1q_f32(ptr_out_thread, vrst);
      ptr_out_thread += 4;
      ptr_in_thread += 4;
    }
    for (int j = 0; j < neon_loop_remain_dim4; ++j) {
      ptr_out_thread[0] =
          ptr_in_thread[0] / (1.0 + expf(-ptr_in_thread[0] * beta));
      ptr_in_thread++;
      ptr_out_thread++;
    }
  }
  float* ptr_out = dout + threads * nums_per_thread;
  const float* ptr_in = din + threads * nums_per_thread;
  for (int j = 0; j < remain; ++j) {
    ptr_out[0] = ptr_in[0] / (1.0 + expf(-ptr_in[0] * beta));
    ptr_in++;
    ptr_out++;
  }
}

}  // namespace math
}  // namespace arm
}  // namespace lite
}  // namespace paddle