164 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			164 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* ----------------------------------------------------------------------
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|  * Project:      CMSIS DSP Library
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|  * Title:        arm_min_q7.c
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|  * Description:  Minimum value of a Q7 vector
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|  *
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|  * $Date:        27. January 2017
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|  * $Revision:    V.1.5.1
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|  *
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|  * Target Processor: Cortex-M cores
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|  * -------------------------------------------------------------------- */
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| /*
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|  * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
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|  *
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|  * SPDX-License-Identifier: Apache-2.0
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|  *
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|  * Licensed under the Apache License, Version 2.0 (the License); you may
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|  * not use this file except in compliance with the License.
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|  * You may obtain a copy of the License at
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|  *
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|  * www.apache.org/licenses/LICENSE-2.0
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|  *
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|  * Unless required by applicable law or agreed to in writing, software
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|  * distributed under the License is distributed on an AS IS BASIS, WITHOUT
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|  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|  * See the License for the specific language governing permissions and
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|  * limitations under the License.
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|  */
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| 
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| #include "arm_math.h"
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| 
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| /**
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|  * @ingroup groupStats
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|  */
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| 
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| 
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| /**
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|  * @addtogroup Min
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|  * @{
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|  */
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| 
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| 
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| /**
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|  * @brief Minimum value of a Q7 vector.
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|  * @param[in]       *pSrc points to the input vector
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|  * @param[in]       blockSize length of the input vector
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|  * @param[out]      *pResult minimum value returned here
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|  * @param[out]      *pIndex index of minimum value returned here
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|  * @return none.
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|  */
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| 
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| void arm_min_q7(
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|   q7_t * pSrc,
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|   uint32_t blockSize,
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|   q7_t * pResult,
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|   uint32_t * pIndex)
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| {
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| #if defined (ARM_MATH_DSP)
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|   /* Run the below code for Cortex-M4 and Cortex-M3 */
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| 
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|   q7_t minVal1, minVal2, out;                    /* Temporary variables to store the output value. */
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|   uint32_t blkCnt, outIndex, count;              /* loop counter */
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| 
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|   /* Initialise the count value. */
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|   count = 0U;
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|   /* Initialise the index value to zero. */
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|   outIndex = 0U;
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|   /* Load first input value that act as reference value for comparision */
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|   out = *pSrc++;
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| 
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|   /* Loop unrolling */
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|   blkCnt = (blockSize - 1U) >> 2U;
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| 
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|   while (blkCnt > 0U)
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|   {
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|     /* Initialize minVal to the next consecutive values one by one */
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|     minVal1 = *pSrc++;
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|     minVal2 = *pSrc++;
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| 
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|     /* compare for the minimum value */
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|     if (out > minVal1)
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|     {
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|       /* Update the minimum value and its index */
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|       out = minVal1;
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|       outIndex = count + 1U;
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|     }
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| 
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|     /* compare for the minimum value */
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|     if (out > minVal2)
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|     {
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|       /* Update the minimum value and its index */
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|       out = minVal2;
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|       outIndex = count + 2U;
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|     }
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| 
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|     /* Initialize minVal to the next consecutive values one by one */
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|     minVal1 = *pSrc++;
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|     minVal2 = *pSrc++;
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| 
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|     /* compare for the minimum value */
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|     if (out > minVal1)
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|     {
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|       /* Update the minimum value and its index */
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|       out = minVal1;
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|       outIndex = count + 3U;
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|     }
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| 
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|     /* compare for the minimum value */
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|     if (out > minVal2)
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|     {
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|       /* Update the minimum value and its index */
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|       out = minVal2;
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|       outIndex = count + 4U;
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|     }
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| 
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|     count += 4U;
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| 
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|     /* Decrement the loop counter */
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|     blkCnt--;
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|   }
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| 
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|   /* if (blockSize - 1U) is not multiple of 4 */
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|   blkCnt = (blockSize - 1U) % 4U;
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| 
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| #else
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|   /* Run the below code for Cortex-M0 */
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| 
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|   q7_t minVal1, out;                             /* Temporary variables to store the output value. */
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|   uint32_t blkCnt, outIndex;                     /* loop counter */
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| 
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|   /* Initialise the index value to zero. */
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|   outIndex = 0U;
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|   /* Load first input value that act as reference value for comparision */
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|   out = *pSrc++;
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| 
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|   blkCnt = (blockSize - 1U);
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| 
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| #endif /* #if defined (ARM_MATH_DSP) */
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| 
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|   while (blkCnt > 0U)
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|   {
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|     /* Initialize minVal to the next consecutive values one by one */
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|     minVal1 = *pSrc++;
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| 
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|     /* compare for the minimum value */
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|     if (out > minVal1)
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|     {
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|       /* Update the minimum value and it's index */
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|       out = minVal1;
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|       outIndex = blockSize - blkCnt;
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|     }
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| 
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|     /* Decrement the loop counter */
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|     blkCnt--;
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|   }
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| 
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|   /* Store the minimum value and it's index into destination pointers */
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|   *pResult = out;
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|   *pIndex = outIndex;
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| }
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| 
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| /**
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|  * @} end of Min group
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|  */
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