00001 /* ---------------------------------------------------------------------- 00002 * Copyright (C) 2010 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 15. July 2011 00005 * $Revision: V1.0.10 00006 * 00007 * Project: CMSIS DSP Library 00008 * Title: arm_abs_q7.c 00009 * 00010 * Description: Q7 vector absolute value. 00011 * 00012 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 00013 * 00014 * Version 1.0.10 2011/7/15 00015 * Big Endian support added and Merged M0 and M3/M4 Source code. 00016 * 00017 * Version 1.0.3 2010/11/29 00018 * Re-organized the CMSIS folders and updated documentation. 00019 * 00020 * Version 1.0.2 2010/11/11 00021 * Documentation updated. 00022 * 00023 * Version 1.0.1 2010/10/05 00024 * Production release and review comments incorporated. 00025 * 00026 * Version 1.0.0 2010/09/20 00027 * Production release and review comments incorporated. 00028 * 00029 * Version 0.0.7 2010/06/10 00030 * Misra-C changes done 00031 * -------------------------------------------------------------------- */ 00032 00033 #include "arm_math.h" 00034 00057 void arm_abs_q7( 00058 q7_t * pSrc, 00059 q7_t * pDst, 00060 uint32_t blockSize) 00061 { 00062 uint32_t blkCnt; /* loop counter */ 00063 00064 #ifndef ARM_MATH_CM0 00065 00066 /* Run the below code for Cortex-M4 and Cortex-M3 */ 00067 q7_t in1; /* Input value1 */ 00068 q7_t in2; /* Input value2 */ 00069 q7_t in3; /* Input value3 */ 00070 q7_t in4; /* Input value4 */ 00071 00072 00073 /*loop Unrolling */ 00074 blkCnt = blockSize >> 2u; 00075 00076 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00077 ** a second loop below computes the remaining 1 to 3 samples. */ 00078 while(blkCnt > 0u) 00079 { 00080 /* C = |A| */ 00081 /* Read 4 inputs */ 00082 in1 = *pSrc++; 00083 in2 = *pSrc++; 00084 in3 = *pSrc++; 00085 in4 = *pSrc++; 00086 00087 /* Store the Absolute result in the destination buffer by packing the 4 values in single cycle */ 00088 *__SIMD32(pDst)++ = 00089 __PACKq7(((in1 > 0) ? in1 : __SSAT(-in1, 8)), 00090 ((in2 > 0) ? in2 : __SSAT(-in2, 8)), 00091 ((in3 > 0) ? in3 : __SSAT(-in3, 8)), 00092 ((in4 > 0) ? in4 : __SSAT(-in4, 8))); 00093 00094 /* Decrement the loop counter */ 00095 blkCnt--; 00096 } 00097 00098 /* If the blockSize is not a multiple of 4, compute any remaining output samples here. 00099 ** No loop unrolling is used. */ 00100 blkCnt = blockSize % 0x4u; 00101 00102 while(blkCnt > 0u) 00103 { 00104 /* C = |A| */ 00105 /* Read the input */ 00106 in1 = *pSrc++; 00107 00108 /* Store the Absolute result in the destination buffer */ 00109 *pDst++ = (in1 > 0) ? in1 : __SSAT(-in1, 8); 00110 00111 /* Decrement the loop counter */ 00112 blkCnt--; 00113 } 00114 00115 #else 00116 00117 /* Run the below code for Cortex-M0 */ 00118 00119 q7_t in; /* Temporary input varible */ 00120 00121 /* Initialize blkCnt with number of samples */ 00122 blkCnt = blockSize; 00123 00124 while(blkCnt > 0u) 00125 { 00126 /* C = |A| */ 00127 /* Read the input */ 00128 in = *pSrc++; 00129 00130 /* Store the Absolute result in the destination buffer */ 00131 *pDst++ = (in > 0) ? in : __SSAT(-in, 8); 00132 00133 /* Decrement the loop counter */ 00134 blkCnt--; 00135 } 00136 00137 #endif /* #ifndef ARM_MATH_CM0 */ 00138 00139 } 00140