1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_mult_q7.c
4 * Description: Q7 vector multiplication
5 *
6 * $Date: 23 April 2021
7 * $Revision: V1.9.0
8 *
9 * Target Processor: Cortex-M and Cortex-A cores
10 * -------------------------------------------------------------------- */
11 /*
12 * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved.
13 *
14 * SPDX-License-Identifier: Apache-2.0
15 *
16 * Licensed under the Apache License, Version 2.0 (the License); you may
17 * not use this file except in compliance with the License.
18 * You may obtain a copy of the License at
19 *
20 * www.apache.org/licenses/LICENSE-2.0
21 *
22 * Unless required by applicable law or agreed to in writing, software
23 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
25 * See the License for the specific language governing permissions and
26 * limitations under the License.
27 */
28
29 #include "dsp/basic_math_functions.h"
30
31 /**
32 @ingroup groupMath
33 */
34
35 /**
36 @addtogroup BasicMult
37 @{
38 */
39
40 /**
41 @brief Q7 vector multiplication
42 @param[in] pSrcA points to the first input vector
43 @param[in] pSrcB points to the second input vector
44 @param[out] pDst points to the output vector
45 @param[in] blockSize number of samples in each vector
46 @return none
47
48 @par Scaling and Overflow Behavior
49 The function uses saturating arithmetic.
50 Results outside of the allowable Q7 range [0x80 0x7F] are saturated.
51 */
52 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
53
54 #include "arm_helium_utils.h"
55
arm_mult_q7(const q7_t * pSrcA,const q7_t * pSrcB,q7_t * pDst,uint32_t blockSize)56 void arm_mult_q7(
57 const q7_t * pSrcA,
58 const q7_t * pSrcB,
59 q7_t * pDst,
60 uint32_t blockSize)
61 {
62 uint32_t blkCnt; /* loop counters */
63 q7x16_t vecA, vecB;
64
65 /* Compute 16 outputs at a time */
66 blkCnt = blockSize >> 4;
67 while (blkCnt > 0U)
68 {
69 /*
70 * C = A * B
71 * Multiply the inputs and then store the results in the destination buffer.
72 */
73 vecA = vld1q(pSrcA);
74 vecB = vld1q(pSrcB);
75 vst1q(pDst, vqdmulhq(vecA, vecB));
76 /*
77 * Decrement the blockSize loop counter
78 */
79 blkCnt--;
80 /*
81 * advance vector source and destination pointers
82 */
83 pSrcA += 16;
84 pSrcB += 16;
85 pDst += 16;
86 }
87 /*
88 * tail
89 */
90 blkCnt = blockSize & 0xF;
91 if (blkCnt > 0U)
92 {
93 mve_pred16_t p0 = vctp8q(blkCnt);
94 vecA = vld1q(pSrcA);
95 vecB = vld1q(pSrcB);
96 vstrbq_p(pDst, vqdmulhq(vecA, vecB), p0);
97 }
98 }
99
100 #else
arm_mult_q7(const q7_t * pSrcA,const q7_t * pSrcB,q7_t * pDst,uint32_t blockSize)101 void arm_mult_q7(
102 const q7_t * pSrcA,
103 const q7_t * pSrcB,
104 q7_t * pDst,
105 uint32_t blockSize)
106 {
107 uint32_t blkCnt; /* Loop counter */
108
109 #if defined (ARM_MATH_LOOPUNROLL)
110
111 #if defined (ARM_MATH_DSP)
112 q7_t out1, out2, out3, out4; /* Temporary output variables */
113 #endif
114
115 /* Loop unrolling: Compute 4 outputs at a time */
116 blkCnt = blockSize >> 2U;
117
118 while (blkCnt > 0U)
119 {
120 /* C = A * B */
121
122 #if defined (ARM_MATH_DSP)
123 /* Multiply inputs and store results in temporary variables */
124 out1 = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
125 out2 = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
126 out3 = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
127 out4 = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
128
129 /* Pack and store result in destination buffer (in single write) */
130 write_q7x4_ia (&pDst, __PACKq7(out1, out2, out3, out4));
131 #else
132 *pDst++ = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
133 *pDst++ = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
134 *pDst++ = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
135 *pDst++ = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
136 #endif
137
138 /* Decrement loop counter */
139 blkCnt--;
140 }
141
142 /* Loop unrolling: Compute remaining outputs */
143 blkCnt = blockSize % 0x4U;
144
145 #else
146
147 /* Initialize blkCnt with number of samples */
148 blkCnt = blockSize;
149
150 #endif /* #if defined (ARM_MATH_LOOPUNROLL) */
151
152 while (blkCnt > 0U)
153 {
154 /* C = A * B */
155
156 /* Multiply input and store result in destination buffer. */
157 *pDst++ = (q7_t) __SSAT((((q15_t) (*pSrcA++) * (*pSrcB++)) >> 7), 8);
158
159 /* Decrement loop counter */
160 blkCnt--;
161 }
162
163 }
164 #endif /* defined(ARM_MATH_MVEI) */
165
166 /**
167 @} end of BasicMult group
168 */
169
