/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_sub_f32.c * Description: Floating-point vector subtraction * * $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 groupMath */ /** @defgroup BasicSub Vector Subtraction Element-by-element subtraction of two vectors.
      pDst[n] = pSrcA[n] - pSrcB[n],   0 <= n < blockSize.
  
There are separate functions for floating-point, Q7, Q15, and Q31 data types. */ /** @addtogroup BasicSub @{ */ /** @brief Floating-point vector subtraction. @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] blockSize number of samples in each vector @return none */ void arm_sub_f32( const float32_t * pSrcA, const float32_t * pSrcB, float32_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* Loop counter */ #if defined (ARM_MATH_LOOPUNROLL) /* Loop unrolling: Compute 4 outputs at a time */ blkCnt = blockSize >> 2U; while (blkCnt > 0U) { /* C = A - B */ /* Subtract and store result in destination buffer. */ *pDst++ = (*pSrcA++) - (*pSrcB++); *pDst++ = (*pSrcA++) - (*pSrcB++); *pDst++ = (*pSrcA++) - (*pSrcB++); *pDst++ = (*pSrcA++) - (*pSrcB++); /* Decrement loop counter */ blkCnt--; } /* Loop unrolling: Compute remaining outputs */ blkCnt = blockSize % 0x4U; #else /* Initialize blkCnt with number of samples */ blkCnt = blockSize; #endif /* #if defined (ARM_MATH_LOOPUNROLL) */ while (blkCnt > 0U) { /* C = A - B */ /* Subtract and store result in destination buffer. */ *pDst++ = (*pSrcA++) - (*pSrcB++); /* Decrement loop counter */ blkCnt--; } } /** @} end of BasicSub group */