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Diffstat (limited to 'Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q31.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q31.c | 847 |
1 files changed, 847 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q31.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q31.c new file mode 100644 index 0000000..78ce505 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q31.c @@ -0,0 +1,847 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_cfft_q31.c + * Description: Combined Radix Decimation in Frequency CFFT fixed point processing function + * + * $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. + */ + +#include "dsp/transform_functions.h" + + + +#if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE) + +#include "arm_vec_fft.h" + + +static void _arm_radix4_butterfly_q31_mve( + const arm_cfft_instance_q31 * S, + q31_t *pSrc, + uint32_t fftLen) +{ + q31x4_t vecTmp0, vecTmp1; + q31x4_t vecSum0, vecDiff0, vecSum1, vecDiff1; + q31x4_t vecA, vecB, vecC, vecD; + uint32_t blkCnt; + uint32_t n1, n2; + uint32_t stage = 0; + int32_t iter = 1; + static const int32_t strides[4] = { + (0 - 16) * (int32_t)sizeof(q31_t *), (1 - 16) * (int32_t)sizeof(q31_t *), + (8 - 16) * (int32_t)sizeof(q31_t *), (9 - 16) * (int32_t)sizeof(q31_t *) + }; + + + /* + * Process first stages + * Each stage in middle stages provides two down scaling of the input + */ + n2 = fftLen; + n1 = n2; + n2 >>= 2u; + + for (int k = fftLen / 4u; k > 1; k >>= 2u) + { + q31_t const *p_rearranged_twiddle_tab_stride2 = + &S->rearranged_twiddle_stride2[ + S->rearranged_twiddle_tab_stride2_arr[stage]]; + q31_t const *p_rearranged_twiddle_tab_stride3 = &S->rearranged_twiddle_stride3[ + S->rearranged_twiddle_tab_stride3_arr[stage]]; + q31_t const *p_rearranged_twiddle_tab_stride1 = + &S->rearranged_twiddle_stride1[ + S->rearranged_twiddle_tab_stride1_arr[stage]]; + + q31_t * pBase = pSrc; + for (int i = 0; i < iter; i++) + { + q31_t *inA = pBase; + q31_t *inB = inA + n2 * CMPLX_DIM; + q31_t *inC = inB + n2 * CMPLX_DIM; + q31_t *inD = inC + n2 * CMPLX_DIM; + q31_t const *pW1 = p_rearranged_twiddle_tab_stride1; + q31_t const *pW2 = p_rearranged_twiddle_tab_stride2; + q31_t const *pW3 = p_rearranged_twiddle_tab_stride3; + q31x4_t vecW; + + + blkCnt = n2 / 2; + /* + * load 2 x q31 complex pair + */ + vecA = vldrwq_s32(inA); + vecC = vldrwq_s32(inC); + while (blkCnt > 0U) + { + vecB = vldrwq_s32(inB); + vecD = vldrwq_s32(inD); + + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * [ 1 1 1 1 ] * [ A B C D ]' .* 1 + */ + vecTmp0 = vhaddq(vecSum0, vecSum1); + vst1q(inA, vecTmp0); + inA += 4; + /* + * [ 1 -1 1 -1 ] * [ A B C D ]' + */ + vecTmp0 = vhsubq(vecSum0, vecSum1); + /* + * [ 1 -1 1 -1 ] * [ A B C D ]'.* W2 + */ + vecW = vld1q(pW2); + pW2 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q31x4_t); + + vst1q(inB, vecTmp1); + inB += 4; + /* + * [ 1 -i -1 +i ] * [ A B C D ]' + */ + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + /* + * [ 1 -i -1 +i ] * [ A B C D ]'.* W1 + */ + vecW = vld1q(pW1); + pW1 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q31x4_t); + vst1q(inC, vecTmp1); + inC += 4; + /* + * [ 1 +i -1 -i ] * [ A B C D ]' + */ + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + /* + * [ 1 +i -1 -i ] * [ A B C D ]'.* W3 + */ + vecW = vld1q(pW3); + pW3 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q31x4_t); + vst1q(inD, vecTmp1); + inD += 4; + + vecA = vldrwq_s32(inA); + vecC = vldrwq_s32(inC); + + blkCnt--; + } + pBase += CMPLX_DIM * n1; + } + n1 = n2; + n2 >>= 2u; + iter = iter << 2; + stage++; + } + + /* + * End of 1st stages process + * data is in 11.21(q21) format for the 1024 point as there are 3 middle stages + * data is in 9.23(q23) format for the 256 point as there are 2 middle stages + * data is in 7.25(q25) format for the 64 point as there are 1 middle stage + * data is in 5.27(q27) format for the 16 point as there are no middle stages + */ + + /* + * start of Last stage process + */ + uint32x4_t vecScGathAddr = vld1q_u32((uint32_t*)strides); + vecScGathAddr = vecScGathAddr + (uint32_t) pSrc; + + /* + * load scheduling + */ + vecA = vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = vldrwq_gather_base_s32(vecScGathAddr, 16); + + blkCnt = (fftLen >> 3); + while (blkCnt > 0U) + { + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecB = vldrwq_gather_base_s32(vecScGathAddr, 8); + vecD = vldrwq_gather_base_s32(vecScGathAddr, 24); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * pre-load for next iteration + */ + vecA = vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = vldrwq_gather_base_s32(vecScGathAddr, 16); + + vecTmp0 = vhaddq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64, vecTmp0); + + vecTmp0 = vhsubq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 8, vecTmp0); + + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 16, vecTmp0); + + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 24, vecTmp0); + + blkCnt--; + } + + /* + * output is in 11.21(q21) format for the 1024 point + * output is in 9.23(q23) format for the 256 point + * output is in 7.25(q25) format for the 64 point + * output is in 5.27(q27) format for the 16 point + */ +} + + +static void arm_cfft_radix4by2_q31_mve(const arm_cfft_instance_q31 *S, q31_t *pSrc, uint32_t fftLen) +{ + uint32_t n2; + q31_t *pIn0; + q31_t *pIn1; + const q31_t *pCoef = S->pTwiddle; + uint32_t blkCnt; + q31x4_t vecIn0, vecIn1, vecSum, vecDiff; + q31x4_t vecCmplxTmp, vecTw; + + n2 = fftLen >> 1; + pIn0 = pSrc; + pIn1 = pSrc + fftLen; + + blkCnt = n2 / 2; + + while (blkCnt > 0U) + { + vecIn0 = vld1q_s32(pIn0); + vecIn1 = vld1q_s32(pIn1); + + vecIn0 = vecIn0 >> 1; + vecIn1 = vecIn1 >> 1; + vecSum = vhaddq(vecIn0, vecIn1); + vst1q(pIn0, vecSum); + pIn0 += 4; + + vecTw = vld1q_s32(pCoef); + pCoef += 4; + vecDiff = vhsubq(vecIn0, vecIn1); + + vecCmplxTmp = MVE_CMPLX_MULT_FX_AxConjB(vecDiff, vecTw, q31x4_t); + vst1q(pIn1, vecCmplxTmp); + pIn1 += 4; + + blkCnt--; + } + + _arm_radix4_butterfly_q31_mve(S, pSrc, n2); + + _arm_radix4_butterfly_q31_mve(S, pSrc + fftLen, n2); + + pIn0 = pSrc; + blkCnt = (fftLen << 1) >> 2; + while (blkCnt > 0U) + { + vecIn0 = vld1q_s32(pIn0); + vecIn0 = vecIn0 << 1; + vst1q(pIn0, vecIn0); + pIn0 += 4; + blkCnt--; + } + /* + * tail + * (will be merged thru tail predication) + */ + blkCnt = (fftLen << 1) & 3; + if (blkCnt > 0U) + { + mve_pred16_t p0 = vctp32q(blkCnt); + + vecIn0 = vld1q_s32(pIn0); + vecIn0 = vecIn0 << 1; + vstrwq_p(pIn0, vecIn0, p0); + } + +} + +static void _arm_radix4_butterfly_inverse_q31_mve( + const arm_cfft_instance_q31 *S, + q31_t *pSrc, + uint32_t fftLen) +{ + q31x4_t vecTmp0, vecTmp1; + q31x4_t vecSum0, vecDiff0, vecSum1, vecDiff1; + q31x4_t vecA, vecB, vecC, vecD; + uint32_t blkCnt; + uint32_t n1, n2; + uint32_t stage = 0; + int32_t iter = 1; + static const int32_t strides[4] = { + (0 - 16) * (int32_t)sizeof(q31_t *), (1 - 16) * (int32_t)sizeof(q31_t *), + (8 - 16) * (int32_t)sizeof(q31_t *), (9 - 16) * (int32_t)sizeof(q31_t *) + }; + + /* + * Process first stages + * Each stage in middle stages provides two down scaling of the input + */ + n2 = fftLen; + n1 = n2; + n2 >>= 2u; + + for (int k = fftLen / 4u; k > 1; k >>= 2u) + { + q31_t const *p_rearranged_twiddle_tab_stride2 = + &S->rearranged_twiddle_stride2[ + S->rearranged_twiddle_tab_stride2_arr[stage]]; + q31_t const *p_rearranged_twiddle_tab_stride3 = &S->rearranged_twiddle_stride3[ + S->rearranged_twiddle_tab_stride3_arr[stage]]; + q31_t const *p_rearranged_twiddle_tab_stride1 = + &S->rearranged_twiddle_stride1[ + S->rearranged_twiddle_tab_stride1_arr[stage]]; + + q31_t * pBase = pSrc; + for (int i = 0; i < iter; i++) + { + q31_t *inA = pBase; + q31_t *inB = inA + n2 * CMPLX_DIM; + q31_t *inC = inB + n2 * CMPLX_DIM; + q31_t *inD = inC + n2 * CMPLX_DIM; + q31_t const *pW1 = p_rearranged_twiddle_tab_stride1; + q31_t const *pW2 = p_rearranged_twiddle_tab_stride2; + q31_t const *pW3 = p_rearranged_twiddle_tab_stride3; + q31x4_t vecW; + + blkCnt = n2 / 2; + /* + * load 2 x q31 complex pair + */ + vecA = vldrwq_s32(inA); + vecC = vldrwq_s32(inC); + while (blkCnt > 0U) + { + vecB = vldrwq_s32(inB); + vecD = vldrwq_s32(inD); + + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * [ 1 1 1 1 ] * [ A B C D ]' .* 1 + */ + vecTmp0 = vhaddq(vecSum0, vecSum1); + vst1q(inA, vecTmp0); + inA += 4; + /* + * [ 1 -1 1 -1 ] * [ A B C D ]' + */ + vecTmp0 = vhsubq(vecSum0, vecSum1); + /* + * [ 1 -1 1 -1 ] * [ A B C D ]'.* W2 + */ + vecW = vld1q(pW2); + pW2 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q31x4_t); + + vst1q(inB, vecTmp1); + inB += 4; + /* + * [ 1 -i -1 +i ] * [ A B C D ]' + */ + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + /* + * [ 1 -i -1 +i ] * [ A B C D ]'.* W1 + */ + vecW = vld1q(pW1); + pW1 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q31x4_t); + vst1q(inC, vecTmp1); + inC += 4; + /* + * [ 1 +i -1 -i ] * [ A B C D ]' + */ + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + /* + * [ 1 +i -1 -i ] * [ A B C D ]'.* W3 + */ + vecW = vld1q(pW3); + pW3 += 4; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q31x4_t); + vst1q(inD, vecTmp1); + inD += 4; + + vecA = vldrwq_s32(inA); + vecC = vldrwq_s32(inC); + + blkCnt--; + } + pBase += CMPLX_DIM * n1; + } + n1 = n2; + n2 >>= 2u; + iter = iter << 2; + stage++; + } + + /* + * End of 1st stages process + * data is in 11.21(q21) format for the 1024 point as there are 3 middle stages + * data is in 9.23(q23) format for the 256 point as there are 2 middle stages + * data is in 7.25(q25) format for the 64 point as there are 1 middle stage + * data is in 5.27(q27) format for the 16 point as there are no middle stages + */ + + /* + * start of Last stage process + */ + uint32x4_t vecScGathAddr = vld1q_u32((uint32_t*)strides); + vecScGathAddr = vecScGathAddr + (uint32_t) pSrc; + + /* + * load scheduling + */ + vecA = vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = vldrwq_gather_base_s32(vecScGathAddr, 16); + + blkCnt = (fftLen >> 3); + while (blkCnt > 0U) + { + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecB = vldrwq_gather_base_s32(vecScGathAddr, 8); + vecD = vldrwq_gather_base_s32(vecScGathAddr, 24); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * pre-load for next iteration + */ + vecA = vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = vldrwq_gather_base_s32(vecScGathAddr, 16); + + vecTmp0 = vhaddq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64, vecTmp0); + + vecTmp0 = vhsubq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 8, vecTmp0); + + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 16, vecTmp0); + + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 24, vecTmp0); + + blkCnt--; + } + /* + * output is in 11.21(q21) format for the 1024 point + * output is in 9.23(q23) format for the 256 point + * output is in 7.25(q25) format for the 64 point + * output is in 5.27(q27) format for the 16 point + */ +} + +static void arm_cfft_radix4by2_inverse_q31_mve(const arm_cfft_instance_q31 *S, q31_t *pSrc, uint32_t fftLen) +{ + uint32_t n2; + q31_t *pIn0; + q31_t *pIn1; + const q31_t *pCoef = S->pTwiddle; + + //uint16_t twidCoefModifier = arm_cfft_radix2_twiddle_factor(S->fftLen); + //q31_t twidIncr = (2 * twidCoefModifier * sizeof(q31_t)); + uint32_t blkCnt; + //uint64x2_t vecOffs; + q31x4_t vecIn0, vecIn1, vecSum, vecDiff; + q31x4_t vecCmplxTmp, vecTw; + + n2 = fftLen >> 1; + + pIn0 = pSrc; + pIn1 = pSrc + fftLen; + //vecOffs[0] = 0; + //vecOffs[1] = (uint64_t) twidIncr; + blkCnt = n2 / 2; + + while (blkCnt > 0U) + { + vecIn0 = vld1q_s32(pIn0); + vecIn1 = vld1q_s32(pIn1); + + vecIn0 = vecIn0 >> 1; + vecIn1 = vecIn1 >> 1; + vecSum = vhaddq(vecIn0, vecIn1); + vst1q(pIn0, vecSum); + pIn0 += 4; + + //vecTw = (q31x4_t) vldrdq_gather_offset_s64(pCoef, vecOffs); + vecTw = vld1q_s32(pCoef); + pCoef += 4; + vecDiff = vhsubq(vecIn0, vecIn1); + + vecCmplxTmp = MVE_CMPLX_MULT_FX_AxB(vecDiff, vecTw, q31x4_t); + vst1q(pIn1, vecCmplxTmp); + pIn1 += 4; + + //vecOffs = vaddq((q31x4_t) vecOffs, 2 * twidIncr); + blkCnt--; + } + + _arm_radix4_butterfly_inverse_q31_mve(S, pSrc, n2); + + _arm_radix4_butterfly_inverse_q31_mve(S, pSrc + fftLen, n2); + + pIn0 = pSrc; + blkCnt = (fftLen << 1) >> 2; + while (blkCnt > 0U) + { + vecIn0 = vld1q_s32(pIn0); + vecIn0 = vecIn0 << 1; + vst1q(pIn0, vecIn0); + pIn0 += 4; + blkCnt--; + } + /* + * tail + * (will be merged thru tail predication) + */ + blkCnt = (fftLen << 1) & 3; + if (blkCnt > 0U) + { + mve_pred16_t p0 = vctp32q(blkCnt); + + vecIn0 = vld1q_s32(pIn0); + vecIn0 = vecIn0 << 1; + vstrwq_p(pIn0, vecIn0, p0); + } + +} + +/** + @ingroup groupTransforms + */ + +/** + @addtogroup ComplexFFT + @{ + */ + +/** + @brief Processing function for the Q31 complex FFT. + @param[in] S points to an instance of the fixed-point CFFT structure + @param[in,out] p1 points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place + @param[in] ifftFlag flag that selects transform direction + - value = 0: forward transform + - value = 1: inverse transform + @param[in] bitReverseFlag flag that enables / disables bit reversal of output + - value = 0: disables bit reversal of output + - value = 1: enables bit reversal of output + @return none + */ +void arm_cfft_q31( + const arm_cfft_instance_q31 * S, + q31_t * pSrc, + uint8_t ifftFlag, + uint8_t bitReverseFlag) +{ + uint32_t fftLen = S->fftLen; + + if (ifftFlag == 1U) { + + switch (fftLen) { + case 16: + case 64: + case 256: + case 1024: + case 4096: + _arm_radix4_butterfly_inverse_q31_mve(S, pSrc, fftLen); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_inverse_q31_mve(S, pSrc, fftLen); + break; + } + } else { + switch (fftLen) { + case 16: + case 64: + case 256: + case 1024: + case 4096: + _arm_radix4_butterfly_q31_mve(S, pSrc, fftLen); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_q31_mve(S, pSrc, fftLen); + break; + } + } + + + if (bitReverseFlag) + { + + arm_bitreversal_32_inpl_mve((uint32_t*)pSrc, S->bitRevLength, S->pBitRevTable); + + } +} +#else + +extern void arm_radix4_butterfly_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef, + uint32_t twidCoefModifier); + +extern void arm_radix4_butterfly_inverse_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef, + uint32_t twidCoefModifier); + +extern void arm_bitreversal_32( + uint32_t * pSrc, + const uint16_t bitRevLen, + const uint16_t * pBitRevTable); + +void arm_cfft_radix4by2_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef); + +void arm_cfft_radix4by2_inverse_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef); + + +/** + @ingroup groupTransforms + */ + +/** + @addtogroup ComplexFFT + @{ + */ + +/** + @brief Processing function for the Q31 complex FFT. + @param[in] S points to an instance of the fixed-point CFFT structure + @param[in,out] p1 points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place + @param[in] ifftFlag flag that selects transform direction + - value = 0: forward transform + - value = 1: inverse transform + @param[in] bitReverseFlag flag that enables / disables bit reversal of output + - value = 0: disables bit reversal of output + - value = 1: enables bit reversal of output + @return none + */ +void arm_cfft_q31( + const arm_cfft_instance_q31 * S, + q31_t * p1, + uint8_t ifftFlag, + uint8_t bitReverseFlag) +{ + uint32_t L = S->fftLen; + + if (ifftFlag == 1U) + { + switch (L) + { + case 16: + case 64: + case 256: + case 1024: + case 4096: + arm_radix4_butterfly_inverse_q31 ( p1, L, (q31_t*)S->pTwiddle, 1 ); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_inverse_q31 ( p1, L, S->pTwiddle ); + break; + } + } + else + { + switch (L) + { + case 16: + case 64: + case 256: + case 1024: + case 4096: + arm_radix4_butterfly_q31 ( p1, L, (q31_t*)S->pTwiddle, 1 ); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_q31 ( p1, L, S->pTwiddle ); + break; + } + } + + if ( bitReverseFlag ) + arm_bitreversal_32 ((uint32_t*) p1, S->bitRevLength, S->pBitRevTable); +} + +/** + @} end of ComplexFFT group + */ + +void arm_cfft_radix4by2_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef) +{ + uint32_t i, l; + uint32_t n2; + q31_t xt, yt, cosVal, sinVal; + q31_t p0, p1; + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + cosVal = pCoef[2 * i]; + sinVal = pCoef[2 * i + 1]; + + l = i + n2; + + xt = (pSrc[2 * i] >> 2U) - (pSrc[2 * l] >> 2U); + pSrc[2 * i] = (pSrc[2 * i] >> 2U) + (pSrc[2 * l] >> 2U); + + yt = (pSrc[2 * i + 1] >> 2U) - (pSrc[2 * l + 1] >> 2U); + pSrc[2 * i + 1] = (pSrc[2 * l + 1] >> 2U) + (pSrc[2 * i + 1] >> 2U); + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multAcc_32x32_keep32_R(p0, yt, sinVal); + multSub_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2 * l] = p0 << 1; + pSrc[2 * l + 1] = p1 << 1; + } + + + /* first col */ + arm_radix4_butterfly_q31 (pSrc, n2, (q31_t*)pCoef, 2U); + + /* second col */ + arm_radix4_butterfly_q31 (pSrc + fftLen, n2, (q31_t*)pCoef, 2U); + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + p0 = pSrc[4 * i + 0]; + p1 = pSrc[4 * i + 1]; + xt = pSrc[4 * i + 2]; + yt = pSrc[4 * i + 3]; + + p0 <<= 1U; + p1 <<= 1U; + xt <<= 1U; + yt <<= 1U; + + pSrc[4 * i + 0] = p0; + pSrc[4 * i + 1] = p1; + pSrc[4 * i + 2] = xt; + pSrc[4 * i + 3] = yt; + } + +} + +void arm_cfft_radix4by2_inverse_q31( + q31_t * pSrc, + uint32_t fftLen, + const q31_t * pCoef) +{ + uint32_t i, l; + uint32_t n2; + q31_t xt, yt, cosVal, sinVal; + q31_t p0, p1; + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + cosVal = pCoef[2 * i]; + sinVal = pCoef[2 * i + 1]; + + l = i + n2; + + xt = (pSrc[2 * i] >> 2U) - (pSrc[2 * l] >> 2U); + pSrc[2 * i] = (pSrc[2 * i] >> 2U) + (pSrc[2 * l] >> 2U); + + yt = (pSrc[2 * i + 1] >> 2U) - (pSrc[2 * l + 1] >> 2U); + pSrc[2 * i + 1] = (pSrc[2 * l + 1] >> 2U) + (pSrc[2 * i + 1] >> 2U); + + mult_32x32_keep32_R(p0, xt, cosVal); + mult_32x32_keep32_R(p1, yt, cosVal); + multSub_32x32_keep32_R(p0, yt, sinVal); + multAcc_32x32_keep32_R(p1, xt, sinVal); + + pSrc[2 * l] = p0 << 1U; + pSrc[2 * l + 1] = p1 << 1U; + } + + /* first col */ + arm_radix4_butterfly_inverse_q31( pSrc, n2, (q31_t*)pCoef, 2U); + + /* second col */ + arm_radix4_butterfly_inverse_q31( pSrc + fftLen, n2, (q31_t*)pCoef, 2U); + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + p0 = pSrc[4 * i + 0]; + p1 = pSrc[4 * i + 1]; + xt = pSrc[4 * i + 2]; + yt = pSrc[4 * i + 3]; + + p0 <<= 1U; + p1 <<= 1U; + xt <<= 1U; + yt <<= 1U; + + pSrc[4 * i + 0] = p0; + pSrc[4 * i + 1] = p1; + pSrc[4 * i + 2] = xt; + pSrc[4 * i + 3] = yt; + } +} +#endif /* defined(ARM_MATH_MVEI) */ |