diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q15.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q15.c | 893 |
1 files changed, 893 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q15.c b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q15.c new file mode 100644 index 0000000..74a6e7a --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/TransformFunctions/arm_cfft_q15.c @@ -0,0 +1,893 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_cfft_q15.c + * Description: Combined Radix Decimation in Q15 Frequency CFFT 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_q15_mve( + const arm_cfft_instance_q15 * S, + q15_t *pSrc, + uint32_t fftLen) +{ + q15x8_t vecTmp0, vecTmp1; + q15x8_t vecSum0, vecDiff0, vecSum1, vecDiff1; + q15x8_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(q15_t *), (4 - 16) * (int32_t)sizeof(q15_t *), + (8 - 16) * (int32_t)sizeof(q15_t *), (12 - 16) * (int32_t)sizeof(q15_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) + { + q15_t const *p_rearranged_twiddle_tab_stride2 = + &S->rearranged_twiddle_stride2[ + S->rearranged_twiddle_tab_stride2_arr[stage]]; + q15_t const *p_rearranged_twiddle_tab_stride3 = &S->rearranged_twiddle_stride3[ + S->rearranged_twiddle_tab_stride3_arr[stage]]; + q15_t const *p_rearranged_twiddle_tab_stride1 = + &S->rearranged_twiddle_stride1[ + S->rearranged_twiddle_tab_stride1_arr[stage]]; + + q15_t * pBase = pSrc; + for (int i = 0; i < iter; i++) + { + q15_t *inA = pBase; + q15_t *inB = inA + n2 * CMPLX_DIM; + q15_t *inC = inB + n2 * CMPLX_DIM; + q15_t *inD = inC + n2 * CMPLX_DIM; + q15_t const *pW1 = p_rearranged_twiddle_tab_stride1; + q15_t const *pW2 = p_rearranged_twiddle_tab_stride2; + q15_t const *pW3 = p_rearranged_twiddle_tab_stride3; + q15x8_t vecW; + + blkCnt = n2 / 4; + /* + * load 4 x q15 complex pair + */ + vecA = vldrhq_s16(inA); + vecC = vldrhq_s16(inC); + while (blkCnt > 0U) + { + vecB = vldrhq_s16(inB); + vecD = vldrhq_s16(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 += 8; + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q15x8_t); + + vst1q(inB, vecTmp1); + inB += 8; + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q15x8_t); + vst1q(inC, vecTmp1); + inC += 8; + + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxB(vecW, vecTmp0, q15x8_t); + vst1q(inD, vecTmp1); + inD += 8; + + vecA = vldrhq_s16(inA); + vecC = vldrhq_s16(inC); + + blkCnt--; + } + pBase += CMPLX_DIM * n1; + } + n1 = n2; + n2 >>= 2u; + iter = iter << 2; + stage++; + } + + /* + * start of Last stage process + */ + uint32x4_t vecScGathAddr = vld1q_u32 ((uint32_t*)strides); + vecScGathAddr = vecScGathAddr + (uint32_t) pSrc; + + /* + * load scheduling + */ + vecA = (q15x8_t) vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 8); + + blkCnt = (fftLen >> 4); + while (blkCnt > 0U) + { + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecB = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 4); + vecD = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 12); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * pre-load for next iteration + */ + vecA = (q15x8_t) vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 8); + + vecTmp0 = vhaddq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64, (int32x4_t) vecTmp0); + + vecTmp0 = vhsubq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 4, (int32x4_t) vecTmp0); + + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 8, (int32x4_t) vecTmp0); + + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 12, (int32x4_t) vecTmp0); + + blkCnt--; + } + +} + +static void arm_cfft_radix4by2_q15_mve(const arm_cfft_instance_q15 *S, q15_t *pSrc, uint32_t fftLen) +{ + uint32_t n2; + q15_t *pIn0; + q15_t *pIn1; + const q15_t *pCoef = S->pTwiddle; + uint32_t blkCnt; + q15x8_t vecIn0, vecIn1, vecSum, vecDiff; + q15x8_t vecCmplxTmp, vecTw; + q15_t const *pCoefVec; + + n2 = fftLen >> 1; + + pIn0 = pSrc; + pIn1 = pSrc + fftLen; + pCoefVec = pCoef; + + blkCnt = n2 / 4; + + while (blkCnt > 0U) + { + vecIn0 = *(q15x8_t *) pIn0; + vecIn1 = *(q15x8_t *) pIn1; + + vecIn0 = vecIn0 >> 1; + vecIn1 = vecIn1 >> 1; + vecSum = vhaddq(vecIn0, vecIn1); + vst1q(pIn0, vecSum); + pIn0 += 8; + + vecTw = vld1q(pCoefVec); + pCoefVec += 8; + + vecDiff = vhsubq(vecIn0, vecIn1); + vecCmplxTmp = MVE_CMPLX_MULT_FX_AxConjB(vecDiff, vecTw, q15x8_t); + vst1q(pIn1, vecCmplxTmp); + pIn1 += 8; + + blkCnt--; + } + + _arm_radix4_butterfly_q15_mve(S, pSrc, n2); + + _arm_radix4_butterfly_q15_mve(S, pSrc + fftLen, n2); + + + pIn0 = pSrc; + blkCnt = (fftLen << 1) >> 3; + while (blkCnt > 0U) + { + vecIn0 = *(q15x8_t *) pIn0; + vecIn0 = vecIn0 << 1; + vst1q(pIn0, vecIn0); + pIn0 += 8; + blkCnt--; + } + /* + * tail + * (will be merged thru tail predication) + */ + blkCnt = (fftLen << 1) & 7; + if (blkCnt > 0U) + { + mve_pred16_t p0 = vctp16q(blkCnt); + + vecIn0 = *(q15x8_t *) pIn0; + vecIn0 = vecIn0 << 1; + vstrhq_p(pIn0, vecIn0, p0); + } +} + +static void _arm_radix4_butterfly_inverse_q15_mve(const arm_cfft_instance_q15 *S,q15_t *pSrc, uint32_t fftLen) +{ + q15x8_t vecTmp0, vecTmp1; + q15x8_t vecSum0, vecDiff0, vecSum1, vecDiff1; + q15x8_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(q15_t *), (4 - 16) * (int32_t)sizeof(q15_t *), + (8 - 16) * (int32_t)sizeof(q15_t *), (12 - 16) * (int32_t)sizeof(q15_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) + { + q15_t const *p_rearranged_twiddle_tab_stride2 = + &S->rearranged_twiddle_stride2[ + S->rearranged_twiddle_tab_stride2_arr[stage]]; + q15_t const *p_rearranged_twiddle_tab_stride3 = &S->rearranged_twiddle_stride3[ + S->rearranged_twiddle_tab_stride3_arr[stage]]; + q15_t const *p_rearranged_twiddle_tab_stride1 = + &S->rearranged_twiddle_stride1[ + S->rearranged_twiddle_tab_stride1_arr[stage]]; + + q15_t * pBase = pSrc; + for (int i = 0; i < iter; i++) + { + q15_t *inA = pBase; + q15_t *inB = inA + n2 * CMPLX_DIM; + q15_t *inC = inB + n2 * CMPLX_DIM; + q15_t *inD = inC + n2 * CMPLX_DIM; + q15_t const *pW1 = p_rearranged_twiddle_tab_stride1; + q15_t const *pW2 = p_rearranged_twiddle_tab_stride2; + q15_t const *pW3 = p_rearranged_twiddle_tab_stride3; + q15x8_t vecW; + + + blkCnt = n2 / 4; + /* + * load 4 x q15 complex pair + */ + vecA = vldrhq_s16(inA); + vecC = vldrhq_s16(inC); + while (blkCnt > 0U) + { + vecB = vldrhq_s16(inB); + vecD = vldrhq_s16(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 += 8; + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q15x8_t); + + vst1q(inB, vecTmp1); + inB += 8; + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q15x8_t); + vst1q(inC, vecTmp1); + inC += 8; + /* + * [ 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 += 8; + vecTmp1 = MVE_CMPLX_MULT_FX_AxConjB(vecTmp0, vecW, q15x8_t); + vst1q(inD, vecTmp1); + inD += 8; + + vecA = vldrhq_s16(inA); + vecC = vldrhq_s16(inC); + + blkCnt--; + } + pBase += CMPLX_DIM * n1; + } + n1 = n2; + n2 >>= 2u; + iter = iter << 2; + stage++; + } + + /* + * start of Last stage process + */ + uint32x4_t vecScGathAddr = vld1q_u32((uint32_t*)strides); + vecScGathAddr = vecScGathAddr + (uint32_t) pSrc; + + /* + * load scheduling + */ + vecA = (q15x8_t) vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 8); + + blkCnt = (fftLen >> 4); + while (blkCnt > 0U) + { + vecSum0 = vhaddq(vecA, vecC); + vecDiff0 = vhsubq(vecA, vecC); + + vecB = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 4); + vecD = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 12); + + vecSum1 = vhaddq(vecB, vecD); + vecDiff1 = vhsubq(vecB, vecD); + /* + * pre-load for next iteration + */ + vecA = (q15x8_t) vldrwq_gather_base_wb_s32(&vecScGathAddr, 64); + vecC = (q15x8_t) vldrwq_gather_base_s32(vecScGathAddr, 8); + + vecTmp0 = vhaddq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64, (int32x4_t) vecTmp0); + + vecTmp0 = vhsubq(vecSum0, vecSum1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 4, (int32x4_t) vecTmp0); + + vecTmp0 = MVE_CMPLX_ADD_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 8, (int32x4_t) vecTmp0); + + vecTmp0 = MVE_CMPLX_SUB_FX_A_ixB(vecDiff0, vecDiff1); + vstrwq_scatter_base_s32(vecScGathAddr, -64 + 12, (int32x4_t) vecTmp0); + + blkCnt--; + } +} + +static void arm_cfft_radix4by2_inverse_q15_mve(const arm_cfft_instance_q15 *S, q15_t *pSrc, uint32_t fftLen) +{ + uint32_t n2; + q15_t *pIn0; + q15_t *pIn1; + const q15_t *pCoef = S->pTwiddle; + + uint32_t blkCnt; + q15x8_t vecIn0, vecIn1, vecSum, vecDiff; + q15x8_t vecCmplxTmp, vecTw; + q15_t const *pCoefVec; + + n2 = fftLen >> 1; + + pIn0 = pSrc; + pIn1 = pSrc + fftLen; + pCoefVec = pCoef; + + blkCnt = n2 / 4; + + while (blkCnt > 0U) + { + vecIn0 = *(q15x8_t *) pIn0; + vecIn1 = *(q15x8_t *) pIn1; + + vecIn0 = vecIn0 >> 1; + vecIn1 = vecIn1 >> 1; + vecSum = vhaddq(vecIn0, vecIn1); + vst1q(pIn0, vecSum); + pIn0 += 8; + + vecTw = vld1q(pCoefVec); + pCoefVec += 8; + + vecDiff = vhsubq(vecIn0, vecIn1); + vecCmplxTmp = vqrdmlsdhq(vuninitializedq_s16() , vecDiff, vecTw); + vecCmplxTmp = vqrdmladhxq(vecCmplxTmp, vecDiff, vecTw); + vst1q(pIn1, vecCmplxTmp); + pIn1 += 8; + + blkCnt--; + } + + + _arm_radix4_butterfly_inverse_q15_mve(S, pSrc, n2); + + _arm_radix4_butterfly_inverse_q15_mve(S, pSrc + fftLen, n2); + + pIn0 = pSrc; + blkCnt = (fftLen << 1) >> 3; + while (blkCnt > 0U) + { + vecIn0 = *(q15x8_t *) pIn0; + vecIn0 = vecIn0 << 1; + vst1q(pIn0, vecIn0); + pIn0 += 8; + blkCnt--; + } + /* + * tail + * (will be merged thru tail predication) + */ + blkCnt = (fftLen << 1) & 7; + while (blkCnt > 0U) + { + mve_pred16_t p0 = vctp16q(blkCnt); + + vecIn0 = *(q15x8_t *) pIn0; + vecIn0 = vecIn0 << 1; + vstrhq_p(pIn0, vecIn0, p0); + } +} + +/** + @ingroup groupTransforms + */ + +/** + @addtogroup ComplexFFT + @{ + */ + +/** + @brief Processing function for Q15 complex FFT. + @param[in] S points to an instance of Q15 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_q15( + const arm_cfft_instance_q15 * S, + q15_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_q15_mve(S, pSrc, fftLen); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_inverse_q15_mve(S, pSrc, fftLen); + break; + } + } else { + switch (fftLen) { + case 16: + case 64: + case 256: + case 1024: + case 4096: + _arm_radix4_butterfly_q15_mve(S, pSrc, fftLen); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_q15_mve(S, pSrc, fftLen); + break; + } + } + + + if (bitReverseFlag) + { + + arm_bitreversal_16_inpl_mve((uint16_t*)pSrc, S->bitRevLength, S->pBitRevTable); + + } +} + +#else + +extern void arm_radix4_butterfly_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef, + uint32_t twidCoefModifier); + +extern void arm_radix4_butterfly_inverse_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef, + uint32_t twidCoefModifier); + +extern void arm_bitreversal_16( + uint16_t * pSrc, + const uint16_t bitRevLen, + const uint16_t * pBitRevTable); + +void arm_cfft_radix4by2_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef); + +void arm_cfft_radix4by2_inverse_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef); + +/** + @ingroup groupTransforms + */ + +/** + @addtogroup ComplexFFT + @{ + */ + +/** + @brief Processing function for Q15 complex FFT. + @param[in] S points to an instance of Q15 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_q15( + const arm_cfft_instance_q15 * S, + q15_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_q15 ( p1, L, (q15_t*)S->pTwiddle, 1 ); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_inverse_q15 ( p1, L, S->pTwiddle ); + break; + } + } + else + { + switch (L) + { + case 16: + case 64: + case 256: + case 1024: + case 4096: + arm_radix4_butterfly_q15 ( p1, L, (q15_t*)S->pTwiddle, 1 ); + break; + + case 32: + case 128: + case 512: + case 2048: + arm_cfft_radix4by2_q15 ( p1, L, S->pTwiddle ); + break; + } + } + + if ( bitReverseFlag ) + arm_bitreversal_16 ((uint16_t*) p1, S->bitRevLength, S->pBitRevTable); +} + +/** + @} end of ComplexFFT group + */ + +void arm_cfft_radix4by2_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef) +{ + uint32_t i; + uint32_t n2; + q15_t p0, p1, p2, p3; +#if defined (ARM_MATH_DSP) + q31_t T, S, R; + q31_t coeff, out1, out2; + const q15_t *pC = pCoef; + q15_t *pSi = pSrc; + q15_t *pSl = pSrc + fftLen; +#else + uint32_t l; + q15_t xt, yt, cosVal, sinVal; +#endif + + n2 = fftLen >> 1U; + +#if defined (ARM_MATH_DSP) + + for (i = n2; i > 0; i--) + { + coeff = read_q15x2_ia (&pC); + + T = read_q15x2 (pSi); + T = __SHADD16(T, 0); /* this is just a SIMD arithmetic shift right by 1 */ + + S = read_q15x2 (pSl); + S = __SHADD16(S, 0); /* this is just a SIMD arithmetic shift right by 1 */ + + R = __QSUB16(T, S); + + write_q15x2_ia (&pSi, __SHADD16(T, S)); + +#ifndef ARM_MATH_BIG_ENDIAN + out1 = __SMUAD(coeff, R) >> 16U; + out2 = __SMUSDX(coeff, R); +#else + out1 = __SMUSDX(R, coeff) >> 16U; + out2 = __SMUAD(coeff, R); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + write_q15x2_ia (&pSl, (q31_t)__PKHBT( out1, out2, 0 ) ); + } + +#else /* #if defined (ARM_MATH_DSP) */ + + for (i = 0; i < n2; i++) + { + cosVal = pCoef[2 * i]; + sinVal = pCoef[2 * i + 1]; + + l = i + n2; + + xt = (pSrc[2 * i] >> 1U) - (pSrc[2 * l] >> 1U); + pSrc[2 * i] = ((pSrc[2 * i] >> 1U) + (pSrc[2 * l] >> 1U)) >> 1U; + + yt = (pSrc[2 * i + 1] >> 1U) - (pSrc[2 * l + 1] >> 1U); + pSrc[2 * i + 1] = ((pSrc[2 * l + 1] >> 1U) + (pSrc[2 * i + 1] >> 1U)) >> 1U; + + pSrc[2 * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16U)) + + ((int16_t) (((q31_t) yt * sinVal) >> 16U)) ); + + pSrc[2 * l + 1] = (((int16_t) (((q31_t) yt * cosVal) >> 16U)) - + ((int16_t) (((q31_t) xt * sinVal) >> 16U)) ); + } + +#endif /* #if defined (ARM_MATH_DSP) */ + + /* first col */ + arm_radix4_butterfly_q15( pSrc, n2, (q15_t*)pCoef, 2U); + + /* second col */ + arm_radix4_butterfly_q15( pSrc + fftLen, n2, (q15_t*)pCoef, 2U); + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + p0 = pSrc[4 * i + 0]; + p1 = pSrc[4 * i + 1]; + p2 = pSrc[4 * i + 2]; + p3 = pSrc[4 * i + 3]; + + p0 <<= 1U; + p1 <<= 1U; + p2 <<= 1U; + p3 <<= 1U; + + pSrc[4 * i + 0] = p0; + pSrc[4 * i + 1] = p1; + pSrc[4 * i + 2] = p2; + pSrc[4 * i + 3] = p3; + } + +} + +void arm_cfft_radix4by2_inverse_q15( + q15_t * pSrc, + uint32_t fftLen, + const q15_t * pCoef) +{ + uint32_t i; + uint32_t n2; + q15_t p0, p1, p2, p3; +#if defined (ARM_MATH_DSP) + q31_t T, S, R; + q31_t coeff, out1, out2; + const q15_t *pC = pCoef; + q15_t *pSi = pSrc; + q15_t *pSl = pSrc + fftLen; +#else + uint32_t l; + q15_t xt, yt, cosVal, sinVal; +#endif + + n2 = fftLen >> 1U; + +#if defined (ARM_MATH_DSP) + + for (i = n2; i > 0; i--) + { + coeff = read_q15x2_ia (&pC); + + T = read_q15x2 (pSi); + T = __SHADD16(T, 0); /* this is just a SIMD arithmetic shift right by 1 */ + + S = read_q15x2 (pSl); + S = __SHADD16(S, 0); /* this is just a SIMD arithmetic shift right by 1 */ + + R = __QSUB16(T, S); + + write_q15x2_ia (&pSi, __SHADD16(T, S)); + +#ifndef ARM_MATH_BIG_ENDIAN + out1 = __SMUSD(coeff, R) >> 16U; + out2 = __SMUADX(coeff, R); +#else + out1 = __SMUADX(R, coeff) >> 16U; + out2 = __SMUSD(__QSUB(0, coeff), R); +#endif /* #ifndef ARM_MATH_BIG_ENDIAN */ + + write_q15x2_ia (&pSl, (q31_t)__PKHBT( out1, out2, 0 )); + } + +#else /* #if defined (ARM_MATH_DSP) */ + + for (i = 0; i < n2; i++) + { + cosVal = pCoef[2 * i]; + sinVal = pCoef[2 * i + 1]; + + l = i + n2; + + xt = (pSrc[2 * i] >> 1U) - (pSrc[2 * l] >> 1U); + pSrc[2 * i] = ((pSrc[2 * i] >> 1U) + (pSrc[2 * l] >> 1U)) >> 1U; + + yt = (pSrc[2 * i + 1] >> 1U) - (pSrc[2 * l + 1] >> 1U); + pSrc[2 * i + 1] = ((pSrc[2 * l + 1] >> 1U) + (pSrc[2 * i + 1] >> 1U)) >> 1U; + + pSrc[2 * l] = (((int16_t) (((q31_t) xt * cosVal) >> 16U)) - + ((int16_t) (((q31_t) yt * sinVal) >> 16U)) ); + + pSrc[2 * l + 1] = (((int16_t) (((q31_t) yt * cosVal) >> 16U)) + + ((int16_t) (((q31_t) xt * sinVal) >> 16U)) ); + } + +#endif /* #if defined (ARM_MATH_DSP) */ + + /* first col */ + arm_radix4_butterfly_inverse_q15( pSrc, n2, (q15_t*)pCoef, 2U); + + /* second col */ + arm_radix4_butterfly_inverse_q15( pSrc + fftLen, n2, (q15_t*)pCoef, 2U); + + n2 = fftLen >> 1U; + for (i = 0; i < n2; i++) + { + p0 = pSrc[4 * i + 0]; + p1 = pSrc[4 * i + 1]; + p2 = pSrc[4 * i + 2]; + p3 = pSrc[4 * i + 3]; + + p0 <<= 1U; + p1 <<= 1U; + p2 <<= 1U; + p3 <<= 1U; + + pSrc[4 * i + 0] = p0; + pSrc[4 * i + 1] = p1; + pSrc[4 * i + 2] = p2; + pSrc[4 * i + 3] = p3; + } +} + +#endif /* defined(ARM_MATH_MVEI) */ |