/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_sub_f16.c * Description: Floating-point vector subtraction * * $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/basic_math_functions_f16.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 */ #if defined(ARM_MATH_MVE_FLOAT16) && !defined(ARM_MATH_AUTOVECTORIZE) #include "arm_helium_utils.h" void arm_sub_f16( const float16_t * pSrcA, const float16_t * pSrcB, float16_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* Loop counter */ f16x8_t vec1; f16x8_t vec2; f16x8_t res; /* Compute 4 outputs at a time */ blkCnt = blockSize >> 3U; while (blkCnt > 0U) { /* C = A + B */ /* Add and then store the results in the destination buffer. */ vec1 = vld1q(pSrcA); vec2 = vld1q(pSrcB); res = vsubq(vec1, vec2); vst1q(pDst, res); /* Increment pointers */ pSrcA += 8; pSrcB += 8; pDst += 8; /* Decrement the loop counter */ blkCnt--; } /* Tail */ blkCnt = blockSize & 0x7; if (blkCnt > 0U) { /* C = A + B */ mve_pred16_t p0 = vctp16q(blkCnt); vec1 = vld1q(pSrcA); vec2 = vld1q(pSrcB); vstrhq_p(pDst, vsubq(vec1,vec2), p0); } } #else #if defined(ARM_FLOAT16_SUPPORTED) void arm_sub_f16( const float16_t * pSrcA, const float16_t * pSrcB, float16_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* Loop counter */ #if defined (ARM_MATH_LOOPUNROLL) && !defined(ARM_MATH_AUTOVECTORIZE) /* 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--; } } #endif #endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */ /** @} end of BasicSub group */