text: /* ----------------------------------------------------------------------
   * Project:      CMSIS DSP Library
   * Title:        arm_cfft_init_q15.c
   * Description:  Initialization function for cfft q15 instance
   *
   * $Date:        23 April 2021
   * $Revision:    V1.9.0
   *
   * Target Processor: Cortex-M and Cortex-A cores
   * -------------------------------------------------------------------- */
  /*
   * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved.
   *
   * SPDX-License-Identifier: Apache-2.0
   *
   * 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
   *
   * 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.
   */
  
  #define FFTINIT(EXT,SIZE)                                           \
    S->bitRevLength = arm_cfft_sR_##EXT##_len##SIZE.bitRevLength;        \
    S->pBitRevTable = arm_cfft_sR_##EXT##_len##SIZE.pBitRevTable;         \
    S->pTwiddle = arm_cfft_sR_##EXT##_len##SIZE.pTwiddle;
  
  /**
    @addtogroup ComplexFFT
    @{
   */
  
  /**
    @brief         Initialization function for the cfft q15 function
    @param[in,out] S              points to an instance of the floating-point CFFT structure
    @param[in]     fftLen         fft length (number of complex samples)
    @return        execution status
                     - \ref ARM_MATH_SUCCESS        : Operation successful
                     - \ref ARM_MATH_ARGUMENT_ERROR : an error is detected
  
    @par          Use of this function is mandatory only for the MVE version of the FFT.
                  Other versions can still initialize directly the data structure using
                  variables declared in arm_const_structs.h
   */
  
  #include "dsp/transform_functions.h"
  #include "arm_common_tables.h"
  #include "arm_const_structs.h"
  
  #if defined(ARM_MATH_MVEI)  && !defined(ARM_MATH_AUTOVECTORIZE)
  
  #include "arm_vec_fft.h"
  #include "arm_mve_tables.h"
  
  
  arm_status arm_cfft_radix4by2_rearrange_twiddles_q15(arm_cfft_instance_q15 *S, int twidCoefModifier)
  {
  
          switch (S->fftLen >> (twidCoefModifier - 1)) {
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_4096) && defined(ARM_TABLE_TWIDDLECOEF_Q15_4096))
          case 4096U:
              S->rearranged_twiddle_tab_stride1_arr = rearranged_twiddle_tab_stride1_arr_4096_q15;
              S->rearranged_twiddle_stride1  =  rearranged_twiddle_stride1_4096_q15;
  
              S->rearranged_twiddle_tab_stride2_arr = rearranged_twiddle_tab_stride2_arr_4096_q15;
              S->rearranged_twiddle_stride2  =  rearranged_twiddle_stride2_4096_q15;
  
              S->rearranged_twiddle_tab_stride3_arr = rearranged_twiddle_tab_stride3_arr_4096_q15;
              S->rearranged_twiddle_stride3  =  rearranged_twiddle_stride3_4096_q15;
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_1024) && defined(ARM_TABLE_TWIDDLECOEF_Q15_1024)) || (defined(ARM_TABLE_BITREVIDX_FXT_2048) && defined(ARM_TABLE_TWIDDLECOEF_Q15_2048))
          case 1024U:
              S->rearranged_twiddle_tab_stride1_arr = rearranged_twiddle_tab_stride1_arr_1024_q15;
              S->rearranged_twiddle_stride1  =  rearranged_twiddle_stride1_1024_q15;
  
              S->rearranged_twiddle_tab_stride2_arr = rearranged_twiddle_tab_stride2_arr_1024_q15;
              S->rearranged_twiddle_stride2  =  rearranged_twiddle_stride2_1024_q15;
  
              S->rearranged_twiddle_tab_stride3_arr = rearranged_twiddle_tab_stride3_arr_1024_q15;
              S->rearranged_twiddle_stride3  =  rearranged_twiddle_stride3_1024_q15;
              break;
   #endif
  
   #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_256) && defined(ARM_TABLE_TWIDDLECOEF_Q15_256)) || (defined(ARM_TABLE_BITREVIDX_FXT_512) && defined(ARM_TABLE_TWIDDLECOEF_Q15_512))
          case 256U:
              S->rearranged_twiddle_tab_stride1_arr = rearranged_twiddle_tab_stride1_arr_256_q15;
              S->rearranged_twiddle_stride1  =  rearranged_twiddle_stride1_256_q15;
  
              S->rearranged_twiddle_tab_stride2_arr = rearranged_twiddle_tab_stride2_arr_256_q15;
              S->rearranged_twiddle_stride2  =  rearranged_twiddle_stride2_256_q15;
  
              S->rearranged_twiddle_tab_stride3_arr = rearranged_twiddle_tab_stride3_arr_256_q15;
              S->rearranged_twiddle_stride3  =  rearranged_twiddle_stride3_256_q15;
  
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_64) && defined(ARM_TABLE_TWIDDLECOEF_Q15_64)) || (defined(ARM_TABLE_BITREVIDX_FXT_128) && defined(ARM_TABLE_TWIDDLECOEF_Q15_128))
          case 64U:
              S->rearranged_twiddle_tab_stride1_arr = rearranged_twiddle_tab_stride1_arr_64_q15;
              S->rearranged_twiddle_stride1  =  rearranged_twiddle_stride1_64_q15;
  
              S->rearranged_twiddle_tab_stride2_arr = rearranged_twiddle_tab_stride2_arr_64_q15;
              S->rearranged_twiddle_stride2  =  rearranged_twiddle_stride2_64_q15;
  
              S->rearranged_twiddle_tab_stride3_arr = rearranged_twiddle_tab_stride3_arr_64_q15;
              S->rearranged_twiddle_stride3  =  rearranged_twiddle_stride3_64_q15;
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_16) && defined(ARM_TABLE_TWIDDLECOEF_Q15_16)) || (defined(ARM_TABLE_BITREVIDX_FXT_32) && defined(ARM_TABLE_TWIDDLECOEF_Q15_32))
          case 16U:
              S->rearranged_twiddle_tab_stride1_arr = rearranged_twiddle_tab_stride1_arr_16_q15;
              S->rearranged_twiddle_stride1  =  rearranged_twiddle_stride1_16_q15;
  
              S->rearranged_twiddle_tab_stride2_arr = rearranged_twiddle_tab_stride2_arr_16_q15;
              S->rearranged_twiddle_stride2  =  rearranged_twiddle_stride2_16_q15;
  
              S->rearranged_twiddle_tab_stride3_arr = rearranged_twiddle_tab_stride3_arr_16_q15;
              S->rearranged_twiddle_stride3  =  rearranged_twiddle_stride3_16_q15;
              break;
  #endif
  
          default:
              return(ARM_MATH_ARGUMENT_ERROR);
              break;
              /* invalid sizes already filtered */
          }
  
          return(ARM_MATH_SUCCESS);
  
  }
  
  
  
  arm_status arm_cfft_init_q15(
    arm_cfft_instance_q15 * S,
    uint16_t fftLen)
  {
  
          /*  Initialise the default arm status */
          arm_status status = ARM_MATH_SUCCESS;
  
          /*  Initialise the FFT length */
          S->fftLen = fftLen;
  
          /*  Initialise the Twiddle coefficient pointer */
          S->pTwiddle = NULL;
  
  
          /*  Initializations of Instance structure depending on the FFT length */
          switch (S->fftLen) {
              /*  Initializations of structure parameters for 4096 point FFT */
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_4096) && defined(ARM_TABLE_TWIDDLECOEF_Q15_4096))
          case 4096U:
              /*  Initialise the bit reversal table modifier */
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_4096_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_4096;
              S->pTwiddle = (q15_t *)twiddleCoef_4096_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 1);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_2048) && defined(ARM_TABLE_TWIDDLECOEF_Q15_2048))
              /*  Initializations of structure parameters for 2048 point FFT */
          case 2048U:
              /*  Initialise the bit reversal table modifier */
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_2048_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_2048;
              S->pTwiddle = (q15_t *)twiddleCoef_2048_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 2);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_1024) && defined(ARM_TABLE_TWIDDLECOEF_Q15_1024))
              /*  Initializations of structure parameters for 1024 point FFT */
          case 1024U:
              /*  Initialise the bit reversal table modifier */
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_1024_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_1024;
              S->pTwiddle = (q15_t *)twiddleCoef_1024_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 1);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_512) && defined(ARM_TABLE_TWIDDLECOEF_Q15_512))
              /*  Initializations of structure parameters for 512 point FFT */
          case 512U:
              /*  Initialise the bit reversal table modifier */
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_512_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_512;
              S->pTwiddle = (q15_t *)twiddleCoef_512_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 2);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_256) && defined(ARM_TABLE_TWIDDLECOEF_Q15_256))
          case 256U:
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_256_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_256;
              S->pTwiddle = (q15_t *)twiddleCoef_256_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 1);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_128) && defined(ARM_TABLE_TWIDDLECOEF_Q15_128))
          case 128U:
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_128_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_128;
              S->pTwiddle = (q15_t *)twiddleCoef_128_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 2);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_64) && defined(ARM_TABLE_TWIDDLECOEF_Q15_64))
          case 64U:
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_64_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_64;
              S->pTwiddle = (q15_t *)twiddleCoef_64_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 1);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_32) && defined(ARM_TABLE_TWIDDLECOEF_Q15_32))
          case 32U:
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_32_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_32;
              S->pTwiddle = (q15_t *)twiddleCoef_32_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 2);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_BITREVIDX_FXT_16) && defined(ARM_TABLE_TWIDDLECOEF_Q15_16))
          case 16U:
              /*  Initializations of structure parameters for 16 point FFT */
              S->bitRevLength = ARMBITREVINDEXTABLE_FIXED_16_TABLE_LENGTH;
              S->pBitRevTable = (uint16_t *)armBitRevIndexTable_fixed_16;
              S->pTwiddle = (q15_t *)twiddleCoef_16_q15;
              status=arm_cfft_radix4by2_rearrange_twiddles_q15(S, 1);
              break;
  #endif
  
          default:
              /*  Reporting argument error if fftSize is not valid value */
              status = ARM_MATH_ARGUMENT_ERROR;
              break;
          }
  
  
          return (status);
  }
  #else
  arm_status arm_cfft_init_q15(
    arm_cfft_instance_q15 * S,
    uint16_t fftLen)
  {
          /*  Initialise the default arm status */
          arm_status status = ARM_MATH_SUCCESS;
  
          /*  Initialise the FFT length */
          S->fftLen = fftLen;
  
          /*  Initialise the Twiddle coefficient pointer */
          S->pTwiddle = NULL;
  
  
          /*  Initializations of Instance structure depending on the FFT length */
          switch (S->fftLen) {
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_4096) && defined(ARM_TABLE_BITREVIDX_FXT_4096))
              /*  Initializations of structure parameters for 4096 point FFT */
          case 4096U:
              /*  Initialise the bit reversal table modifier */
              FFTINIT(q15,4096);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_2048) && defined(ARM_TABLE_BITREVIDX_FXT_2048))
              /*  Initializations of structure parameters for 2048 point FFT */
          case 2048U:
              /*  Initialise the bit reversal table modifier */
              FFTINIT(q15,2048);
  
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_1024) && defined(ARM_TABLE_BITREVIDX_FXT_1024))
              /*  Initializations of structure parameters for 1024 point FFT */
          case 1024U:
              /*  Initialise the bit reversal table modifier */
              FFTINIT(q15,1024);
  
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_512) && defined(ARM_TABLE_BITREVIDX_FXT_512))
              /*  Initializations of structure parameters for 512 point FFT */
          case 512U:
              /*  Initialise the bit reversal table modifier */
              FFTINIT(q15,512);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_256) && defined(ARM_TABLE_BITREVIDX_FXT_256))
          case 256U:
              FFTINIT(q15,256);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_128) && defined(ARM_TABLE_BITREVIDX_FXT_128))
          case 128U:
              FFTINIT(q15,128);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_64) && defined(ARM_TABLE_BITREVIDX_FXT_64))
          case 64U:
              FFTINIT(q15,64);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_32) && defined(ARM_TABLE_BITREVIDX_FXT_32))
          case 32U:
              FFTINIT(q15,32);
              break;
  #endif
  
  #if !defined(ARM_DSP_CONFIG_TABLES) || defined(ARM_ALL_FFT_TABLES) || (defined(ARM_TABLE_TWIDDLECOEF_Q15_16) && defined(ARM_TABLE_BITREVIDX_FXT_16))
          case 16U:
              /*  Initializations of structure parameters for 16 point FFT */
              FFTINIT(q15,16);
              break;
  #endif
  
          default:
              /*  Reporting argument error if fftSize is not valid value */
              status = ARM_MATH_ARGUMENT_ERROR;
              break;
          }
  
  
          return (status);
  }
  #endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */
  
  /**
    @} end of ComplexFFT group
   */
  