| /* ---------------------------------------------------------------------- |
| * Copyright (C) 2010 ARM Limited. All rights reserved. |
| * |
| * $Date: 15. July 2011 |
| * $Revision: V1.0.10 |
| * |
| * Project: CMSIS DSP Library |
| * Title: arm_cmplx_mult_cmplx_q31.c |
| * |
| * Description: Q31 complex-by-complex multiplication |
| * |
| * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 |
| * |
| * Version 1.0.10 2011/7/15 |
| * Big Endian support added and Merged M0 and M3/M4 Source code. |
| * |
| * Version 1.0.3 2010/11/29 |
| * Re-organized the CMSIS folders and updated documentation. |
| * |
| * Version 1.0.2 2010/11/11 |
| * Documentation updated. |
| * |
| * Version 1.0.1 2010/10/05 |
| * Production release and review comments incorporated. |
| * |
| * Version 1.0.0 2010/09/20 |
| * Production release and review comments incorporated. |
| * -------------------------------------------------------------------- */ |
| |
| #include "arm_math.h" |
| |
| /** |
| * @ingroup groupCmplxMath |
| */ |
| |
| /** |
| * @addtogroup CmplxByCmplxMult |
| * @{ |
| */ |
| |
| |
| /** |
| * @brief Q31 complex-by-complex multiplication |
| * @param[in] *pSrcA points to the first input vector |
| * @param[in] *pSrcB points to the second input vector |
| * @param[out] *pDst points to the output vector |
| * @param[in] numSamples number of complex samples in each vector |
| * @return none. |
| * |
| * <b>Scaling and Overflow Behavior:</b> |
| * \par |
| * The function implements 1.31 by 1.31 multiplications and finally output is converted into 3.29 format. |
| * Input down scaling is not required. |
| */ |
| |
| void arm_cmplx_mult_cmplx_q31( |
| q31_t * pSrcA, |
| q31_t * pSrcB, |
| q31_t * pDst, |
| uint32_t numSamples) |
| { |
| q31_t a, b, c, d; /* Temporary variables to store real and imaginary values */ |
| uint32_t blkCnt; /* loop counters */ |
| |
| #ifndef ARM_MATH_CM0 |
| |
| /* Run the below code for Cortex-M4 and Cortex-M3 */ |
| |
| /* loop Unrolling */ |
| blkCnt = numSamples >> 2u; |
| |
| /* First part of the processing with loop unrolling. Compute 4 outputs at a time. |
| ** a second loop below computes the remaining 1 to 3 samples. */ |
| while(blkCnt > 0u) |
| { |
| /* C[2 * i] = A[2 * i] * B[2 * i] - A[2 * i + 1] * B[2 * i + 1]. */ |
| /* C[2 * i + 1] = A[2 * i] * B[2 * i + 1] + A[2 * i + 1] * B[2 * i]. */ |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the real result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the imag result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| /* Decrement the blockSize loop counter */ |
| blkCnt--; |
| } |
| |
| /* If the blockSize is not a multiple of 4, compute any remaining output samples here. |
| ** No loop unrolling is used. */ |
| blkCnt = numSamples % 0x4u; |
| |
| while(blkCnt > 0u) |
| { |
| /* C[2 * i] = A[2 * i] * B[2 * i] - A[2 * i + 1] * B[2 * i + 1]. */ |
| /* C[2 * i + 1] = A[2 * i] * B[2 * i + 1] + A[2 * i + 1] * B[2 * i]. */ |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| /* Decrement the blockSize loop counter */ |
| blkCnt--; |
| } |
| |
| #else |
| |
| /* Run the below code for Cortex-M0 */ |
| |
| /* loop Unrolling */ |
| blkCnt = numSamples >> 1u; |
| |
| /* First part of the processing with loop unrolling. Compute 2 outputs at a time. |
| ** a second loop below computes the remaining 1 sample. */ |
| while(blkCnt > 0u) |
| { |
| /* C[2 * i] = A[2 * i] * B[2 * i] - A[2 * i + 1] * B[2 * i + 1]. */ |
| /* C[2 * i + 1] = A[2 * i] * B[2 * i + 1] + A[2 * i + 1] * B[2 * i]. */ |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the real result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the imag result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| /* Decrement the blockSize loop counter */ |
| blkCnt--; |
| } |
| |
| /* If the blockSize is not a multiple of 2, compute any remaining output samples here. |
| ** No loop unrolling is used. */ |
| blkCnt = numSamples % 0x2u; |
| |
| while(blkCnt > 0u) |
| { |
| /* C[2 * i] = A[2 * i] * B[2 * i] - A[2 * i + 1] * B[2 * i + 1]. */ |
| /* C[2 * i + 1] = A[2 * i] * B[2 * i + 1] + A[2 * i + 1] * B[2 * i]. */ |
| a = *pSrcA++; |
| b = *pSrcA++; |
| c = *pSrcB++; |
| d = *pSrcB++; |
| |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * c) >> 33) - (((q63_t) b * d) >> 33)); |
| /* store the result in 3.29 format in the destination buffer. */ |
| *pDst++ = (q31_t) ((((q63_t) a * d) >> 33) + (((q63_t) b * c) >> 33)); |
| |
| /* Decrement the blockSize loop counter */ |
| blkCnt--; |
| } |
| |
| #endif /* #ifndef ARM_MATH_CM0 */ |
| |
| } |
| |
| /** |
| * @} end of CmplxByCmplxMult group |
| */ |