| /* ---------------------------------------------------------------------- |
| * Project: CMSIS DSP Library |
| * Title: arm_mat_mult_q31.c |
| * Description: Q31 matrix multiplication |
| * |
| * $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 groupMatrix |
| */ |
| |
| /** |
| @addtogroup MatrixMult |
| @{ |
| */ |
| |
| /** |
| @brief Q31 matrix multiplication. |
| @param[in] pSrcA points to the first input matrix structure |
| @param[in] pSrcB points to the second input matrix structure |
| @param[out] pDst points to output matrix structure |
| @return execution status |
| - \ref ARM_MATH_SUCCESS : Operation successful |
| - \ref ARM_MATH_SIZE_MISMATCH : Matrix size check failed |
| |
| @par Scaling and Overflow Behavior |
| The function is implemented using an internal 64-bit accumulator. |
| The accumulator has a 2.62 format and maintains full precision of the intermediate |
| multiplication results but provides only a single guard bit. There is no saturation |
| on intermediate additions. Thus, if the accumulator overflows it wraps around and |
| distorts the result. The input signals should be scaled down to avoid intermediate |
| overflows. The input is thus scaled down by log2(numColsA) bits |
| to avoid overflows, as a total of numColsA additions are performed internally. |
| The 2.62 accumulator is right shifted by 31 bits and saturated to 1.31 format to yield the final result. |
| @remark |
| Refer to \ref arm_mat_mult_fast_q31() for a faster but less precise implementation of this function. |
| */ |
| |
| arm_status arm_mat_mult_q31( |
| const arm_matrix_instance_q31 * pSrcA, |
| const arm_matrix_instance_q31 * pSrcB, |
| arm_matrix_instance_q31 * pDst) |
| { |
| q31_t *pIn1 = pSrcA->pData; /* Input data matrix pointer A */ |
| q31_t *pIn2 = pSrcB->pData; /* Input data matrix pointer B */ |
| q31_t *pInA = pSrcA->pData; /* Input data matrix pointer A */ |
| q31_t *pInB = pSrcB->pData; /* Input data matrix pointer B */ |
| q31_t *pOut = pDst->pData; /* Output data matrix pointer */ |
| q31_t *px; /* Temporary output data matrix pointer */ |
| q63_t sum; /* Accumulator */ |
| uint16_t numRowsA = pSrcA->numRows; /* Number of rows of input matrix A */ |
| uint16_t numColsB = pSrcB->numCols; /* Number of columns of input matrix B */ |
| uint16_t numColsA = pSrcA->numCols; /* Number of columns of input matrix A */ |
| uint32_t col, i = 0U, row = numRowsA, colCnt; /* Loop counters */ |
| arm_status status; /* Status of matrix multiplication */ |
| |
| #ifdef ARM_MATH_MATRIX_CHECK |
| |
| /* Check for matrix mismatch condition */ |
| if ((pSrcA->numCols != pSrcB->numRows) || |
| (pSrcA->numRows != pDst->numRows) || |
| (pSrcB->numCols != pDst->numCols) ) |
| { |
| /* Set status as ARM_MATH_SIZE_MISMATCH */ |
| status = ARM_MATH_SIZE_MISMATCH; |
| } |
| else |
| |
| #endif /* #ifdef ARM_MATH_MATRIX_CHECK */ |
| |
| { |
| /* The following loop performs the dot-product of each row in pSrcA with each column in pSrcB */ |
| /* row loop */ |
| do |
| { |
| /* Output pointer is set to starting address of row being processed */ |
| px = pOut + i; |
| |
| /* For every row wise process, column loop counter is to be initiated */ |
| col = numColsB; |
| |
| /* For every row wise process, pIn2 pointer is set to starting address of pSrcB data */ |
| pIn2 = pSrcB->pData; |
| |
| /* column loop */ |
| do |
| { |
| /* Set the variable sum, that acts as accumulator, to zero */ |
| sum = 0; |
| |
| /* Initialize pointer pIn1 to point to starting address of column being processed */ |
| pIn1 = pInA; |
| |
| #if defined (ARM_MATH_LOOPUNROLL) |
| |
| /* Loop unrolling: Compute 4 MACs at a time. */ |
| colCnt = numColsA >> 2U; |
| |
| /* matrix multiplication */ |
| while (colCnt > 0U) |
| { |
| /* c(m,n) = a(1,1) * b(1,1) + a(1,2) * b(2,1) + .... + a(m,p) * b(p,n) */ |
| |
| /* Perform the multiply-accumulates */ |
| sum += (q63_t) *pIn1++ * *pIn2; |
| pIn2 += numColsB; |
| |
| sum += (q63_t) *pIn1++ * *pIn2; |
| pIn2 += numColsB; |
| |
| sum += (q63_t) *pIn1++ * *pIn2; |
| pIn2 += numColsB; |
| |
| sum += (q63_t) *pIn1++ * *pIn2; |
| pIn2 += numColsB; |
| |
| /* Decrement loop counter */ |
| colCnt--; |
| } |
| |
| /* Loop unrolling: Compute remaining MACs */ |
| colCnt = numColsA % 0x4U; |
| |
| #else |
| |
| /* Initialize cntCnt with number of columns */ |
| colCnt = numColsA; |
| |
| #endif /* #if defined (ARM_MATH_LOOPUNROLL) */ |
| |
| while (colCnt > 0U) |
| { |
| /* c(m,n) = a(1,1) * b(1,1) + a(1,2) * b(2,1) + .... + a(m,p) * b(p,n) */ |
| |
| /* Perform the multiply-accumulates */ |
| sum += (q63_t) *pIn1++ * *pIn2; |
| pIn2 += numColsB; |
| |
| /* Decrement loop counter */ |
| colCnt--; |
| } |
| |
| /* Convert result from 2.62 to 1.31 format and store in destination buffer */ |
| *px++ = (q31_t) (sum >> 31); |
| |
| /* Decrement column loop counter */ |
| col--; |
| |
| /* Update pointer pIn2 to point to starting address of next column */ |
| pIn2 = pInB + (numColsB - col); |
| |
| } while (col > 0U); |
| |
| /* Update pointer pInA to point to starting address of next row */ |
| i = i + numColsB; |
| pInA = pInA + numColsA; |
| |
| /* Decrement row loop counter */ |
| row--; |
| |
| } while (row > 0U); |
| |
| /* Set status as ARM_MATH_SUCCESS */ |
| status = ARM_MATH_SUCCESS; |
| } |
| |
| /* Return to application */ |
| return (status); |
| } |
| |
| /** |
| @} end of MatrixMult group |
| */ |