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author | Ali Labbene <ali.labbene@st.com> | 2019-12-11 08:59:21 +0100 |
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committer | Ali Labbene <ali.labbene@st.com> | 2019-12-16 16:35:24 +0100 |
commit | 9f95ff5b6ba01db09552b84a0ab79607060a2666 (patch) | |
tree | 8a6e0dda832555c692307869aed49d07ee7facfe /DSP/Source/BasicMathFunctions/arm_abs_q7.c | |
parent | 76177aa280494bb36d7a0bcbda1078d4db717020 (diff) | |
download | st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.tar.gz st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.tar.bz2 st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.zip |
Official ARM version: v5.4.0
Add CMSIS V5.4.0, please refer to index.html available under \docs folder.
Note: content of \CMSIS\Core\Include has been copied under \Include to keep the same structure
used in existing projects, and thus avoid projects mass update
Note: the following components have been removed from ARM original delivery (as not used in ST packages)
- CMSIS_EW2018.pdf
- .gitattributes
- .gitignore
- \Device
- \CMSIS
- \CoreValidation
- \DAP
- \Documentation
- \DoxyGen
- \Driver
- \Pack
- \RTOS\CMSIS_RTOS_Tutorial.pdf
- \RTOS\RTX
- \RTOS\Template
- \RTOS2\RTX
- \Utilities
- All ARM/GCC projects files are deleted from \DSP, \RTOS and \RTOS2
Change-Id: Ia026c3f0f0d016627a4fb5a9032852c33d24b4d3
Diffstat (limited to 'DSP/Source/BasicMathFunctions/arm_abs_q7.c')
-rw-r--r-- | DSP/Source/BasicMathFunctions/arm_abs_q7.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/DSP/Source/BasicMathFunctions/arm_abs_q7.c b/DSP/Source/BasicMathFunctions/arm_abs_q7.c new file mode 100644 index 0000000..d0acbfc --- /dev/null +++ b/DSP/Source/BasicMathFunctions/arm_abs_q7.c @@ -0,0 +1,145 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_abs_q7.c + * Description: Q7 vector absolute value + * + * $Date: 27. January 2017 + * $Revision: V.1.5.1 + * + * Target Processor: Cortex-M cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2017 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 BasicAbs + * @{ + */ + +/** + * @brief Q7 vector absolute value. + * @param[in] *pSrc points to the input buffer + * @param[out] *pDst points to the output buffer + * @param[in] blockSize number of samples in each vector + * @return none. + * + * \par Conditions for optimum performance + * Input and output buffers should be aligned by 32-bit + * + * + * <b>Scaling and Overflow Behavior:</b> + * \par + * The function uses saturating arithmetic. + * The Q7 value -1 (0x80) will be saturated to the maximum allowable positive value 0x7F. + */ + +void arm_abs_q7( + q7_t * pSrc, + q7_t * pDst, + uint32_t blockSize) +{ + uint32_t blkCnt; /* loop counter */ + q7_t in; /* Input value1 */ + +#if defined (ARM_MATH_DSP) + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + q31_t in1, in2, in3, in4; /* temporary input variables */ + q31_t out1, out2, out3, out4; /* temporary output variables */ + + /*loop Unrolling */ + blkCnt = blockSize >> 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 = |A| */ + /* Read inputs */ + in1 = (q31_t) * pSrc; + in2 = (q31_t) * (pSrc + 1); + in3 = (q31_t) * (pSrc + 2); + + /* find absolute value */ + out1 = (in1 > 0) ? in1 : (q31_t)__QSUB8(0, in1); + + /* read input */ + in4 = (q31_t) * (pSrc + 3); + + /* find absolute value */ + out2 = (in2 > 0) ? in2 : (q31_t)__QSUB8(0, in2); + + /* store result to destination */ + *pDst = (q7_t) out1; + + /* find absolute value */ + out3 = (in3 > 0) ? in3 : (q31_t)__QSUB8(0, in3); + + /* find absolute value */ + out4 = (in4 > 0) ? in4 : (q31_t)__QSUB8(0, in4); + + /* store result to destination */ + *(pDst + 1) = (q7_t) out2; + + /* store result to destination */ + *(pDst + 2) = (q7_t) out3; + + /* store result to destination */ + *(pDst + 3) = (q7_t) out4; + + /* update pointers to process next samples */ + pSrc += 4U; + pDst += 4U; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* If the blockSize is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = blockSize % 0x4U; +#else + + /* Run the below code for Cortex-M0 */ + blkCnt = blockSize; + +#endif /* #define ARM_MATH_CM0_FAMILY */ + + while (blkCnt > 0U) + { + /* C = |A| */ + /* Read the input */ + in = *pSrc++; + + /* Store the Absolute result in the destination buffer */ + *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? 0x7f : -in); + + /* Decrement the loop counter */ + blkCnt--; + } +} + +/** + * @} end of BasicAbs group + */ |