122 lines
3.3 KiB
C
122 lines
3.3 KiB
C
|
/* ----------------------------------------------------------------------
|
||
|
|
* Project: CMSIS DSP Library
|
||
|
|
* Title: arm_offset_q15.c
|
||
|
|
* Description: Q15 vector offset
|
||
|
|
*
|
||
|
|
* $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
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
@addtogroup BasicOffset
|
||
|
|
@{
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
@brief Adds a constant offset to a Q15 vector.
|
||
|
|
@param[in] pSrc points to the input vector
|
||
|
|
@param[in] offset is the offset to be added
|
||
|
|
@param[out] pDst points to the output vector
|
||
|
|
@param[in] blockSize number of samples in each vector
|
||
|
|
@return none
|
||
|
|
|
||
|
|
@par Scaling and Overflow Behavior
|
||
|
|
The function uses saturating arithmetic.
|
||
|
|
Results outside of the allowable Q15 range [0x8000 0x7FFF] are saturated.
|
||
|
|
*/
|
||
|
|
|
||
|
|
void arm_offset_q15(
|
||
|
|
const q15_t * pSrc,
|
||
|
|
q15_t offset,
|
||
|
|
q15_t * pDst,
|
||
|
|
uint32_t blockSize)
|
||
|
|
{
|
||
|
|
uint32_t blkCnt; /* Loop counter */
|
||
|
|
|
||
|
|
#if defined (ARM_MATH_LOOPUNROLL)
|
||
|
|
|
||
|
|
#if defined (ARM_MATH_DSP)
|
||
|
|
q31_t offset_packed; /* Offset packed to 32 bit */
|
||
|
|
|
||
|
|
/* Offset is packed to 32 bit in order to use SIMD32 for addition */
|
||
|
|
offset_packed = __PKHBT(offset, offset, 16);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* Loop unrolling: Compute 4 outputs at a time */
|
||
|
|
blkCnt = blockSize >> 2U;
|
||
|
|
|
||
|
|
while (blkCnt > 0U)
|
||
|
|
{
|
||
|
|
/* C = A + offset */
|
||
|
|
|
||
|
|
#if defined (ARM_MATH_DSP)
|
||
|
|
/* Add offset and store result in destination buffer (2 samples at a time). */
|
||
|
|
write_q15x2_ia (&pDst, __QADD16(read_q15x2_ia ((q15_t **) &pSrc), offset_packed));
|
||
|
|
write_q15x2_ia (&pDst, __QADD16(read_q15x2_ia ((q15_t **) &pSrc), offset_packed));
|
||
|
|
#else
|
||
|
|
*pDst++ = (q15_t) __SSAT(((q31_t) *pSrc++ + offset), 16);
|
||
|
|
*pDst++ = (q15_t) __SSAT(((q31_t) *pSrc++ + offset), 16);
|
||
|
|
*pDst++ = (q15_t) __SSAT(((q31_t) *pSrc++ + offset), 16);
|
||
|
|
*pDst++ = (q15_t) __SSAT(((q31_t) *pSrc++ + offset), 16);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* 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 + offset */
|
||
|
|
|
||
|
|
/* Add offset and store result in destination buffer. */
|
||
|
|
#if defined (ARM_MATH_DSP)
|
||
|
|
*pDst++ = (q15_t) __QADD16(*pSrc++, offset);
|
||
|
|
#else
|
||
|
|
*pDst++ = (q15_t) __SSAT(((q31_t) *pSrc++ + offset), 16);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* Decrement loop counter */
|
||
|
|
blkCnt--;
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
@} end of BasicOffset group
|
||
|
|
*/
|