00001 /* ---------------------------------------------------------------------- 00002 * Copyright (C) 2010 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 29. November 2010 00005 * $Revision: V1.0.3 00006 * 00007 * Project: CMSIS DSP Library 00008 * Title: arm_sub_f32.c 00009 * 00010 * Description: Floating-point vector subtraction. 00011 * 00012 * Target Processor: Cortex-M4/Cortex-M3 00013 * 00014 * Version 1.0.3 2010/11/29 00015 * Re-organized the CMSIS folders and updated documentation. 00016 * 00017 * Version 1.0.2 2010/11/11 00018 * Documentation updated. 00019 * 00020 * Version 1.0.1 2010/10/05 00021 * Production release and review comments incorporated. 00022 * 00023 * Version 1.0.0 2010/09/20 00024 * Production release and review comments incorporated. 00025 * 00026 * Version 0.0.7 2010/06/10 00027 * Misra-C changes done 00028 * ---------------------------------------------------------------------------- */ 00029 00030 #include "arm_math.h" 00031 00063 void arm_sub_f32( 00064 float32_t * pSrcA, 00065 float32_t * pSrcB, 00066 float32_t * pDst, 00067 uint32_t blockSize) 00068 { 00069 uint32_t blkCnt; /* loop counter */ 00070 00071 /*loop Unrolling */ 00072 blkCnt = blockSize >> 2u; 00073 00074 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00075 ** a second loop below computes the remaining 1 to 3 samples. */ 00076 while(blkCnt > 0u) 00077 { 00078 /* C = A - B */ 00079 /* Subtract and then store the results in the destination buffer. */ 00080 *pDst++ = (*pSrcA++) - (*pSrcB++); 00081 *pDst++ = (*pSrcA++) - (*pSrcB++); 00082 *pDst++ = (*pSrcA++) - (*pSrcB++); 00083 *pDst++ = (*pSrcA++) - (*pSrcB++); 00084 00085 /* Decrement the loop counter */ 00086 blkCnt--; 00087 } 00088 00089 /* If the blockSize is not a multiple of 4, compute any remaining output samples here. 00090 ** No loop unrolling is used. */ 00091 blkCnt = blockSize % 0x4u; 00092 00093 while(blkCnt > 0u) 00094 { 00095 /* C = A - B */ 00096 /* Subtract and then store the results in the destination buffer. */ 00097 *pDst++ = (*pSrcA++) - (*pSrcB++); 00098 00099 /* Decrement the loop counter */ 00100 blkCnt--; 00101 } 00102 } 00103