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diff --git a/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_dot_prod_q31.c b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_dot_prod_q31.c
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+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_dot_prod_q31.c
+ * Description: Q31 dot product
+ *
+ * $Date: 18. March 2019
+ * $Revision: V1.6.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2019 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 BasicDotProd
+ @{
+ */
+
+/**
+ @brief Dot product of Q31 vectors.
+ @param[in] pSrcA points to the first input vector.
+ @param[in] pSrcB points to the second input vector.
+ @param[in] blockSize number of samples in each vector.
+ @param[out] result output result returned here.
+ @return none
+
+ @par Scaling and Overflow Behavior
+ The intermediate multiplications are in 1.31 x 1.31 = 2.62 format and these
+ are truncated to 2.48 format by discarding the lower 14 bits.
+ The 2.48 result is then added without saturation to a 64-bit accumulator in 16.48 format.
+ There are 15 guard bits in the accumulator and there is no risk of overflow as long as
+ the length of the vectors is less than 2^16 elements.
+ The return result is in 16.48 format.
+ */
+
+void arm_dot_prod_q31(
+ const q31_t * pSrcA,
+ const q31_t * pSrcB,
+ uint32_t blockSize,
+ q63_t * result)
+{
+ uint32_t blkCnt; /* Loop counter */
+ q63_t sum = 0; /* Temporary return variable */
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+ /* Loop unrolling: Compute 4 outputs at a time */
+ blkCnt = blockSize >> 2U;
+
+ while (blkCnt > 0U)
+ {
+ /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */
+
+ /* Calculate dot product and store result in a temporary buffer. */
+ sum += ((q63_t) *pSrcA++ * *pSrcB++) >> 14U;
+
+ sum += ((q63_t) *pSrcA++ * *pSrcB++) >> 14U;
+
+ sum += ((q63_t) *pSrcA++ * *pSrcB++) >> 14U;
+
+ sum += ((q63_t) *pSrcA++ * *pSrcB++) >> 14U;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+
+ /* Loop unrolling: Compute remaining outputs */
+ blkCnt = blockSize % 0x4U;
+
+#else
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
+
+ while (blkCnt > 0U)
+ {
+ /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */
+
+ /* Calculate dot product and store result in a temporary buffer. */
+ sum += ((q63_t) *pSrcA++ * *pSrcB++) >> 14U;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+
+ /* Store result in destination buffer in 16.48 format */
+ *result = sum;
+}
+
+/**
+ @} end of BasicDotProd group
+ */