/* ---------------------------------------------------------------------- * Copyright (C) 2010-2013 ARM Limited. All rights reserved. * * $Date: 17. January 2013 * $Revision: V1.4.1 * * Project: CMSIS DSP Library * Title: arm_mult_f32.c * * Description: Floating-point vector multiplication. * * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * - Neither the name of ARM LIMITED nor the names of its contributors * may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * -------------------------------------------------------------------- */ #include "arm_math.h" /** * @ingroup groupMath */ /** * @defgroup BasicMult Vector Multiplication * * Element-by-element multiplication of two vectors. * *
        
 *     pDst[n] = pSrcA[n] * pSrcB[n],   0 <= n < blockSize.        
 * 
* * There are separate functions for floating-point, Q7, Q15, and Q31 data types. */ /** * @addtogroup BasicMult * @{ */ /** * @brief Floating-point vector multiplication. * @param[in] *pSrcA points to the first input vector * @param[in] *pSrcB points to the second input vector * @param[out] *pDst points to the output vector * @param[in] blockSize number of samples in each vector * @return none. */ void arm_mult_f32( float32_t * pSrcA, float32_t * pSrcB, float32_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* loop counters */ #ifndef ARM_MATH_CM0_FAMILY /* Run the below code for Cortex-M4 and Cortex-M3 */ float32_t inA1, inA2, inA3, inA4; /* temporary input variables */ float32_t inB1, inB2, inB3, inB4; /* temporary input variables */ float32_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 * B */ /* Multiply the inputs and store the results in output buffer */ /* read sample from sourceA */ inA1 = *pSrcA; /* read sample from sourceB */ inB1 = *pSrcB; /* read sample from sourceA */ inA2 = *(pSrcA + 1); /* read sample from sourceB */ inB2 = *(pSrcB + 1); /* out = sourceA * sourceB */ out1 = inA1 * inB1; /* read sample from sourceA */ inA3 = *(pSrcA + 2); /* read sample from sourceB */ inB3 = *(pSrcB + 2); /* out = sourceA * sourceB */ out2 = inA2 * inB2; /* read sample from sourceA */ inA4 = *(pSrcA + 3); /* store result to destination buffer */ *pDst = out1; /* read sample from sourceB */ inB4 = *(pSrcB + 3); /* out = sourceA * sourceB */ out3 = inA3 * inB3; /* store result to destination buffer */ *(pDst + 1) = out2; /* out = sourceA * sourceB */ out4 = inA4 * inB4; /* store result to destination buffer */ *(pDst + 2) = out3; /* store result to destination buffer */ *(pDst + 3) = out4; /* update pointers to process next samples */ pSrcA += 4u; pSrcB += 4u; pDst += 4u; /* Decrement the blockSize 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 */ /* Initialize blkCnt with number of samples */ blkCnt = blockSize; #endif /* #ifndef ARM_MATH_CM0_FAMILY */ while(blkCnt > 0u) { /* C = A * B */ /* Multiply the inputs and store the results in output buffer */ *pDst++ = (*pSrcA++) * (*pSrcB++); /* Decrement the blockSize loop counter */ blkCnt--; } } /** * @} end of BasicMult group */