text: // Copyright (C) 2019. Huawei Technologies Co., Ltd. All rights reserved.
  
  // Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"),
  // to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
  // and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
  
  // The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
  
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
  // WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  #ifndef _H_ARM_FUNCTIONS_INT8
  #define _H_ARM_FUNCTIONS_INT8
  #include "arm_neon_expand.h"
  
  inline EE activation_int8(INT8 *input, U32 len, ActivationParamSpec activationDesc, INT8 *output)
  {
      int8x16_t in, out;
      int8x16_t zero = vdupq_n_s8(0);
      U32 len_main = len / 16;
      U32 len_tail = len % 16;
  
      switch (activationDesc.mode) {
          case ACTIVATION_NULL: {
              break;
          }
          case ACTIVATION_RELU: {
              if (activationDesc.value[0] != 0) {
                  return NOT_SUPPORTED;
              }
              for (U32 i = 0; i < len_main; i++) {
                  in = vld1q_s8(input);
                  out = vmaxq_s8(zero, in);
                  vst1q_s8(output, out);
                  input += 16;
                  output += 16;
              }
              for (U32 i = 0; i < len_tail; i++) {
                  output[i] = (input[i] < 0) ? 0 : input[i];
              }
              break;
          }
          default:
              return NOT_SUPPORTED;
      }
  
      return SUCCESS;
  }
  #endif
  