| /* ---------------------------------------------------------------------- |
| * Project: CMSIS DSP Library |
| * Title: arm_cmplx_dot_prod_f32.c |
| * Description: Floating-point complex dot product |
| * |
| * $Date: 18. March 2019 |
| * $Revision: V1.6.0 |
| * |
| * Target Processor: Cortex-M cores |
| * -------------------------------------------------------------------- */ |
| /* |
| * Copyright (C) 2010-2019 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 "arm_math.h" |
| |
| /** |
| @ingroup groupCmplxMath |
| */ |
| |
| /** |
| @defgroup cmplx_dot_prod Complex Dot Product |
| |
| Computes the dot product of two complex vectors. |
| The vectors are multiplied element-by-element and then summed. |
| |
| The <code>pSrcA</code> points to the first complex input vector and |
| <code>pSrcB</code> points to the second complex input vector. |
| <code>numSamples</code> specifies the number of complex samples |
| and the data in each array is stored in an interleaved fashion |
| (real, imag, real, imag, ...). |
| Each array has a total of <code>2*numSamples</code> values. |
| |
| The underlying algorithm is used: |
| |
| <pre> |
| realResult = 0; |
| imagResult = 0; |
| for (n = 0; n < numSamples; n++) { |
| realResult += pSrcA[(2*n)+0] * pSrcB[(2*n)+0] - pSrcA[(2*n)+1] * pSrcB[(2*n)+1]; |
| imagResult += pSrcA[(2*n)+0] * pSrcB[(2*n)+1] + pSrcA[(2*n)+1] * pSrcB[(2*n)+0]; |
| } |
| </pre> |
| |
| There are separate functions for floating-point, Q15, and Q31 data types. |
| */ |
| |
| /** |
| @addtogroup cmplx_dot_prod |
| @{ |
| */ |
| |
| /** |
| @brief Floating-point complex dot product. |
| @param[in] pSrcA points to the first input vector |
| @param[in] pSrcB points to the second input vector |
| @param[in] numSamples number of samples in each vector |
| @param[out] realResult real part of the result returned here |
| @param[out] imagResult imaginary part of the result returned here |
| @return none |
| */ |
| |
| void arm_cmplx_dot_prod_f32( |
| const float32_t * pSrcA, |
| const float32_t * pSrcB, |
| uint32_t numSamples, |
| float32_t * realResult, |
| float32_t * imagResult) |
| { |
| uint32_t blkCnt; /* Loop counter */ |
| float32_t real_sum = 0.0f, imag_sum = 0.0f; /* Temporary result variables */ |
| float32_t a0,b0,c0,d0; |
| |
| #if defined(ARM_MATH_NEON) |
| float32x4x2_t vec1,vec2,vec3,vec4; |
| float32x4_t accR,accI; |
| float32x2_t accum = vdup_n_f32(0); |
| |
| accR = vdupq_n_f32(0.0); |
| accI = vdupq_n_f32(0.0); |
| |
| /* Loop unrolling: Compute 8 outputs at a time */ |
| blkCnt = numSamples >> 3U; |
| |
| while (blkCnt > 0U) |
| { |
| /* C = (A[0]+jA[1])*(B[0]+jB[1]) + ... */ |
| /* Calculate dot product and then store the result in a temporary buffer. */ |
| |
| vec1 = vld2q_f32(pSrcA); |
| vec2 = vld2q_f32(pSrcB); |
| |
| /* Increment pointers */ |
| pSrcA += 8; |
| pSrcB += 8; |
| |
| /* Re{C} = Re{A}*Re{B} - Im{A}*Im{B} */ |
| accR = vmlaq_f32(accR,vec1.val[0],vec2.val[0]); |
| accR = vmlsq_f32(accR,vec1.val[1],vec2.val[1]); |
| |
| /* Im{C} = Re{A}*Im{B} + Im{A}*Re{B} */ |
| accI = vmlaq_f32(accI,vec1.val[1],vec2.val[0]); |
| accI = vmlaq_f32(accI,vec1.val[0],vec2.val[1]); |
| |
| vec3 = vld2q_f32(pSrcA); |
| vec4 = vld2q_f32(pSrcB); |
| |
| /* Increment pointers */ |
| pSrcA += 8; |
| pSrcB += 8; |
| |
| /* Re{C} = Re{A}*Re{B} - Im{A}*Im{B} */ |
| accR = vmlaq_f32(accR,vec3.val[0],vec4.val[0]); |
| accR = vmlsq_f32(accR,vec3.val[1],vec4.val[1]); |
| |
| /* Im{C} = Re{A}*Im{B} + Im{A}*Re{B} */ |
| accI = vmlaq_f32(accI,vec3.val[1],vec4.val[0]); |
| accI = vmlaq_f32(accI,vec3.val[0],vec4.val[1]); |
| |
| /* Decrement the loop counter */ |
| blkCnt--; |
| } |
| |
| accum = vpadd_f32(vget_low_f32(accR), vget_high_f32(accR)); |
| real_sum += accum[0] + accum[1]; |
| |
| accum = vpadd_f32(vget_low_f32(accI), vget_high_f32(accI)); |
| imag_sum += accum[0] + accum[1]; |
| |
| /* Tail */ |
| blkCnt = numSamples & 0x7; |
| |
| #else |
| #if defined (ARM_MATH_LOOPUNROLL) |
| |
| /* Loop unrolling: Compute 4 outputs at a time */ |
| blkCnt = numSamples >> 2U; |
| |
| while (blkCnt > 0U) |
| { |
| a0 = *pSrcA++; |
| b0 = *pSrcA++; |
| c0 = *pSrcB++; |
| d0 = *pSrcB++; |
| |
| real_sum += a0 * c0; |
| imag_sum += a0 * d0; |
| real_sum -= b0 * d0; |
| imag_sum += b0 * c0; |
| |
| a0 = *pSrcA++; |
| b0 = *pSrcA++; |
| c0 = *pSrcB++; |
| d0 = *pSrcB++; |
| |
| real_sum += a0 * c0; |
| imag_sum += a0 * d0; |
| real_sum -= b0 * d0; |
| imag_sum += b0 * c0; |
| |
| a0 = *pSrcA++; |
| b0 = *pSrcA++; |
| c0 = *pSrcB++; |
| d0 = *pSrcB++; |
| |
| real_sum += a0 * c0; |
| imag_sum += a0 * d0; |
| real_sum -= b0 * d0; |
| imag_sum += b0 * c0; |
| |
| a0 = *pSrcA++; |
| b0 = *pSrcA++; |
| c0 = *pSrcB++; |
| d0 = *pSrcB++; |
| |
| real_sum += a0 * c0; |
| imag_sum += a0 * d0; |
| real_sum -= b0 * d0; |
| imag_sum += b0 * c0; |
| |
| /* Decrement loop counter */ |
| blkCnt--; |
| } |
| |
| /* Loop unrolling: Compute remaining outputs */ |
| blkCnt = numSamples % 0x4U; |
| |
| #else |
| |
| /* Initialize blkCnt with number of samples */ |
| blkCnt = numSamples; |
| |
| #endif /* #if defined (ARM_MATH_LOOPUNROLL) */ |
| #endif /* #if defined(ARM_MATH_NEON) */ |
| |
| while (blkCnt > 0U) |
| { |
| a0 = *pSrcA++; |
| b0 = *pSrcA++; |
| c0 = *pSrcB++; |
| d0 = *pSrcB++; |
| |
| real_sum += a0 * c0; |
| imag_sum += a0 * d0; |
| real_sum -= b0 * d0; |
| imag_sum += b0 * c0; |
| |
| /* Decrement loop counter */ |
| blkCnt--; |
| } |
| |
| /* Store real and imaginary result in destination buffer. */ |
| *realResult = real_sum; |
| *imagResult = imag_sum; |
| } |
| |
| /** |
| @} end of cmplx_dot_prod group |
| */ |