| /* ---------------------------------------------------------------------- | |
| * Project: CMSIS DSP Library | |
| * Title: arm_mat_mult_fast_q15.c | |
| * Description: Q15 matrix multiplication (fast variant) | |
| * | |
| * $Date: 23 April 2021 | |
| * $Revision: V1.9.0 | |
| * | |
| * Target Processor: Cortex-M and Cortex-A cores | |
| * -------------------------------------------------------------------- */ | |
| /* | |
| * Copyright (C) 2010-2021 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. | |
| */ | |
| /** | |
| @ingroup groupMatrix | |
| */ | |
| /** | |
| @addtogroup MatrixMult | |
| @{ | |
| */ | |
| /** | |
| @brief Q15 matrix multiplication (fast variant). | |
| @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 | |
| @param[in] pState points to the array for storing intermediate results | |
| @return execution status | |
| - \ref ARM_MATH_SUCCESS : Operation successful | |
| - \ref ARM_MATH_SIZE_MISMATCH : Matrix size check failed | |
| @par Scaling and Overflow Behavior | |
| The difference between the function \ref arm_mat_mult_q15() and this fast variant is that | |
| the fast variant use a 32-bit rather than a 64-bit accumulator. | |
| The result of each 1.15 x 1.15 multiplication is truncated to | |
| 2.30 format. These intermediate results are accumulated in a 32-bit register in 2.30 | |
| format. Finally, the accumulator is saturated and converted to a 1.15 result. | |
| @par | |
| The fast version has the same overflow behavior as the standard version but provides | |
| less precision since it discards the low 16 bits of each multiplication result. | |
| In order to avoid overflows completely the input signals must be scaled down. | |
| Scale down one of the input matrices by log2(numColsA) bits to avoid overflows, | |
| as a total of numColsA additions are computed internally for each output element. | |
| @remark | |
| Refer to \ref arm_mat_mult_q15() for a slower implementation of this function | |
| which uses 64-bit accumulation to provide higher precision. | |
| */ | |
| arm_status arm_mat_mult_fast_q15( | |
| const arm_matrix_instance_q15 * pSrcA, | |
| const arm_matrix_instance_q15 * pSrcB, | |
| arm_matrix_instance_q15 * pDst, | |
| q15_t * pState) | |
| { | |
| q31_t sum; /* Accumulator */ | |
| q15_t *pSrcBT = pState; /* Input data matrix pointer for transpose */ | |
| q15_t *pInA = pSrcA->pData; /* Input data matrix pointer A of Q15 type */ | |
| q15_t *pInB = pSrcB->pData; /* Input data matrix pointer B of Q15 type */ | |
| q15_t *px; /* Temporary output data matrix pointer */ | |
| 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 */ | |
| uint16_t numRowsB = pSrcB->numRows; /* Number of rows of input matrix B */ | |
| uint32_t col, i = 0U, row = numRowsB, colCnt; /* Loop counters */ | |
| arm_status status; /* Status of matrix multiplication */ | |
| q31_t in; /* Temporary variable to hold the input value */ | |
| q31_t inA1, inB1, inA2, inB2; | |
| q31_t sum2, sum3, sum4; | |
| q15_t *pInA2, *pInB2, *px2; | |
| uint32_t j = 0; | |
| q15_t in; /* Temporary variable to hold the input value */ | |
| q15_t inA1, inB1, inA2, inB2; | |
| /* 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 | |
| { | |
| /* Matrix transpose */ | |
| do | |
| { | |
| /* The pointer px is set to starting address of column being processed */ | |
| px = pSrcBT + i; | |
| /* Apply loop unrolling and exchange columns with row elements */ | |
| col = numColsB >> 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 (col > 0U) | |
| { | |
| /* Read two elements from row */ | |
| in = read_q15x2_ia (&pInB); | |
| /* Unpack and store one element in destination */ | |
| *px = (q15_t) in; | |
| *px = (q15_t) ((in & (q31_t) 0xffff0000) >> 16); | |
| /* Update pointer px to point to next row of transposed matrix */ | |
| px += numRowsB; | |
| /* Unpack and store second element in destination */ | |
| *px = (q15_t) ((in & (q31_t) 0xffff0000) >> 16); | |
| *px = (q15_t) in; | |
| /* Update pointer px to point to next row of transposed matrix */ | |
| px += numRowsB; | |
| in = read_q15x2_ia (&pInB); | |
| *px = (q15_t) in; | |
| *px = (q15_t) ((in & (q31_t) 0xffff0000) >> 16); | |
| px += numRowsB; | |
| *px = (q15_t) ((in & (q31_t) 0xffff0000) >> 16); | |
| *px = (q15_t) in; | |
| px += numRowsB; | |
| /* Read one element from row */ | |
| in = *pInB++; | |
| /* Store one element in destination */ | |
| *px = in; | |
| /* Update pointer px to point to next row of transposed matrix */ | |
| px += numRowsB; | |
| in = *pInB++; | |
| *px = in; | |
| px += numRowsB; | |
| in = *pInB++; | |
| *px = in; | |
| px += numRowsB; | |
| in = *pInB++; | |
| *px = in; | |
| px += numRowsB; | |
| /* Decrement column loop counter */ | |
| col--; | |
| } | |
| /* If the columns of pSrcB is not a multiple of 4, compute any remaining output samples here. | |
| ** No loop unrolling is used. */ | |
| col = numColsB % 0x4U; | |
| while (col > 0U) | |
| { | |
| /* Read and store input element in destination */ | |
| *px = *pInB++; | |
| /* Update pointer px to point to next row of transposed matrix */ | |
| px += numRowsB; | |
| /* Decrement column loop counter */ | |
| col--; | |
| } | |
| i++; | |
| /* Decrement row loop counter */ | |
| row--; | |
| } while (row > 0U); | |
| /* Reset variables for usage in following multiplication process */ | |
| row = numRowsA; | |
| i = 0U; | |
| px = pDst->pData; | |
| /* Process two rows from matrix A at a time and output two rows at a time */ | |
| row = row >> 1U; | |
| px2 = px + numColsB; | |
| /* The following loop performs the dot-product of each row in pSrcA with each column in pSrcB */ | |
| /* row loop */ | |
| while (row > 0U) | |
| { | |
| /* 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 transposed pSrcB data */ | |
| pInB = pSrcBT; | |
| /* Process two (transposed) columns from matrix B at a time */ | |
| col = col >> 1U; | |
| j = 0; | |
| /* column loop */ | |
| while (col > 0U) | |
| { | |
| /* Set variable sum, that acts as accumulator, to zero */ | |
| sum = 0; | |
| /* Initiate pointer pInA to point to starting address of column being processed */ | |
| pInA = pSrcA->pData + i; | |
| sum2 = 0; | |
| sum3 = 0; | |
| sum4 = 0; | |
| pInB = pSrcBT + j; | |
| pInA2 = pInA + numColsA; | |
| pInB2 = pInB + numRowsB; | |
| /* Read in two elements at once - allows dual MAC instruction */ | |
| colCnt = numColsA >> 1U; | |
| 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) */ | |
| /* read real and imag values from pSrcA and pSrcB buffer */ | |
| inA1 = read_q15x2_ia (&pInA); | |
| inB1 = read_q15x2_ia (&pInB); | |
| inA2 = read_q15x2_ia (&pInA2); | |
| inB2 = read_q15x2_ia (&pInB2); | |
| /* Multiply and Accumulates */ | |
| sum = __SMLAD(inA1, inB1, sum); | |
| sum2 = __SMLAD(inA1, inB2, sum2); | |
| sum3 = __SMLAD(inA2, inB1, sum3); | |
| sum4 = __SMLAD(inA2, inB2, sum4); | |
| /* read real and imag values from pSrcA and pSrcB buffer */ | |
| inA1 = *pInA++; | |
| inB1 = *pInB++; | |
| /* Multiply and Accumulates */ | |
| sum += inA1 * inB1; | |
| inA2 = *pInA++; | |
| inB2 = *pInB++; | |
| sum += inA2 * inB2; | |
| inA1 = *pInA++; | |
| inB1 = *pInB++; | |
| sum += inA1 * inB1; | |
| inA2 = *pInA++; | |
| inB2 = *pInB++; | |
| sum += inA2 * inB2; | |
| /* Decrement loop counter */ | |
| colCnt--; | |
| } | |
| /* process odd column samples */ | |
| if (numColsA & 1U) { | |
| inA1 = *pInA++; | |
| inB1 = *pInB++; | |
| inA2 = *pInA2++; | |
| inB2 = *pInB2++; | |
| sum += inA1 * inB1; | |
| sum2 += inA1 * inB2; | |
| sum3 += inA2 * inB1; | |
| sum4 += inA2 * inB2; | |
| } | |
| colCnt = numColsA % 0x4U; | |
| while (colCnt > 0U) | |
| { | |
| /* c(m,n) = a(1,1) * b(1,1) + a(1,2) * b(2,1) + .... + a(m,p) * b(p,n) */ | |
| sum += (q31_t) *pInA++ * *pInB++; | |
| /* Decrement loop counter */ | |
| colCnt--; | |
| } | |
| /* Saturate and store result in destination buffer */ | |
| *px++ = (q15_t) (sum >> 15); | |
| *px++ = (q15_t) (sum2 >> 15); | |
| *px2++ = (q15_t) (sum3 >> 15); | |
| *px2++ = (q15_t) (sum4 >> 15); | |
| j += numRowsB * 2; | |
| /* Decrement column loop counter */ | |
| col--; | |
| } | |
| i = i + numColsA; | |
| i = i + numColsA; | |
| px = px2 + (numColsB & 1U); | |
| px2 = px + numColsB; | |
| /* Decrement row loop counter */ | |
| row--; | |
| } | |
| /* Compute any remaining odd row/column below */ | |
| /* Compute remaining output column */ | |
| if (numColsB & 1U) { | |
| /* Avoid redundant computation of last element */ | |
| row = numRowsA & (~0x1); | |
| /* Point to remaining unfilled column in output matrix */ | |
| px = pDst->pData + numColsB-1; | |
| pInA = pSrcA->pData; | |
| /* row loop */ | |
| while (row > 0) | |
| { | |
| /* point to last column in matrix B */ | |
| pInB = pSrcBT + numRowsB * (numColsB-1); | |
| /* Set variable sum, that acts as accumulator, to zero */ | |
| sum = 0; | |
| /* Compute 4 columns at once */ | |
| colCnt = numColsA >> 2U; | |
| /* matrix multiplication */ | |
| while (colCnt > 0U) | |
| { | |
| inA1 = read_q15x2_ia (&pInA); | |
| inA2 = read_q15x2_ia (&pInA); | |
| inB1 = read_q15x2_ia (&pInB); | |
| inB2 = read_q15x2_ia (&pInB); | |
| sum = __SMLAD(inA1, inB1, sum); | |
| sum = __SMLAD(inA2, inB2, sum); | |
| /* Decrement loop counter */ | |
| colCnt--; | |
| } | |
| colCnt = numColsA & 3U; | |
| while (colCnt > 0U) { | |
| sum += (q31_t) (*pInA++) * (*pInB++); | |
| colCnt--; | |
| } | |
| /* Store result in destination buffer */ | |
| *px = (q15_t) (sum >> 15); | |
| px += numColsB; | |
| /* Decrement row loop counter */ | |
| row--; | |
| } | |
| } | |
| /* Compute remaining output row */ | |
| if (numRowsA & 1U) { | |
| /* point to last row in output matrix */ | |
| px = pDst->pData + (numColsB) * (numRowsA-1); | |
| pInB = pSrcBT; | |
| col = numColsB; | |
| i = 0U; | |
| /* col loop */ | |
| while (col > 0) | |
| { | |
| /* point to last row in matrix A */ | |
| pInA = pSrcA->pData + (numRowsA-1) * numColsA; | |
| /* Set variable sum, that acts as accumulator, to zero */ | |
| sum = 0; | |
| /* Compute 4 columns at once */ | |
| colCnt = numColsA >> 2U; | |
| /* matrix multiplication */ | |
| while (colCnt > 0U) | |
| { | |
| inA1 = read_q15x2_ia (&pInA); | |
| inA2 = read_q15x2_ia (&pInA); | |
| inB1 = read_q15x2_ia (&pInB); | |
| inB2 = read_q15x2_ia (&pInB); | |
| sum = __SMLAD(inA1, inB1, sum); | |
| sum = __SMLAD(inA2, inB2, sum); | |
| /* Decrement loop counter */ | |
| colCnt--; | |
| } | |
| colCnt = numColsA % 4U; | |
| while (colCnt > 0U) { | |
| sum += (q31_t) (*pInA++) * (*pInB++); | |
| colCnt--; | |
| } | |
| /* Store result in destination buffer */ | |
| *px++ = (q15_t) (sum >> 15); | |
| /* Decrement column loop counter */ | |
| col--; | |
| } | |
| } | |
| /* Set status as ARM_MATH_SUCCESS */ | |
| status = ARM_MATH_SUCCESS; | |
| } | |
| /* Return to application */ | |
| return (status); | |
| } | |
| /** | |
| @} end of MatrixMult group | |
| */ | |