1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_add_q15.c
4 * Description: Q15 vector addition
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 BasicAdd
37 @{
38 */
39
40 /**
41 @brief Q15 vector addition.
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 Q15 range [0x8000 0x7FFF] are saturated.
51 */
52
53 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
54
55 #include "arm_helium_utils.h"
56
arm_add_q15(const q15_t * pSrcA,const q15_t * pSrcB,q15_t * pDst,uint32_t blockSize)57 void arm_add_q15(
58 const q15_t * pSrcA,
59 const q15_t * pSrcB,
60 q15_t * pDst,
61 uint32_t blockSize)
62 {
63 uint32_t blkCnt; /* loop counters */
64 q15x8_t vecA;
65 q15x8_t vecB;
66
67 /* Compute 8 outputs at a time */
68 blkCnt = blockSize >> 3;
69 while (blkCnt > 0U)
70 {
71 /*
72 * C = A + B
73 * Add and then store the results in the destination buffer.
74 */
75 vecA = vld1q(pSrcA);
76 vecB = vld1q(pSrcB);
77 vst1q(pDst, vqaddq(vecA, vecB));
78 /*
79 * Decrement the blockSize loop counter
80 */
81 blkCnt--;
82 /*
83 * advance vector source and destination pointers
84 */
85 pSrcA += 8;
86 pSrcB += 8;
87 pDst += 8;
88 }
89 /*
90 * tail
91 */
92 blkCnt = blockSize & 7;
93 if (blkCnt > 0U)
94 {
95 mve_pred16_t p0 = vctp16q(blkCnt);
96 vecA = vld1q(pSrcA);
97 vecB = vld1q(pSrcB);
98 vstrhq_p(pDst, vqaddq(vecA, vecB), p0);
99 }
100 }
101
102 #else
arm_add_q15(const q15_t * pSrcA,const q15_t * pSrcB,q15_t * pDst,uint32_t blockSize)103 void arm_add_q15(
104 const q15_t * pSrcA,
105 const q15_t * pSrcB,
106 q15_t * pDst,
107 uint32_t blockSize)
108 {
109 uint32_t blkCnt; /* Loop counter */
110
111 #if defined (ARM_MATH_LOOPUNROLL)
112
113 #if defined (ARM_MATH_DSP)
114 q31_t inA1, inA2;
115 q31_t inB1, inB2;
116 #endif
117
118 /* Loop unrolling: Compute 4 outputs at a time */
119 blkCnt = blockSize >> 2U;
120
121 while (blkCnt > 0U)
122 {
123 /* C = A + B */
124
125 #if defined (ARM_MATH_DSP)
126 /* read 2 times 2 samples at a time from sourceA */
127 inA1 = read_q15x2_ia ((q15_t **) &pSrcA);
128 inA2 = read_q15x2_ia ((q15_t **) &pSrcA);
129 /* read 2 times 2 samples at a time from sourceB */
130 inB1 = read_q15x2_ia ((q15_t **) &pSrcB);
131 inB2 = read_q15x2_ia ((q15_t **) &pSrcB);
132
133 /* Add and store 2 times 2 samples at a time */
134 write_q15x2_ia (&pDst, __QADD16(inA1, inB1));
135 write_q15x2_ia (&pDst, __QADD16(inA2, inB2));
136 #else
137 *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ + *pSrcB++), 16);
138 *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ + *pSrcB++), 16);
139 *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ + *pSrcB++), 16);
140 *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ + *pSrcB++), 16);
141 #endif
142
143 /* Decrement loop counter */
144 blkCnt--;
145 }
146
147 /* Loop unrolling: Compute remaining outputs */
148 blkCnt = blockSize % 0x4U;
149
150 #else
151
152 /* Initialize blkCnt with number of samples */
153 blkCnt = blockSize;
154
155 #endif /* #if defined (ARM_MATH_LOOPUNROLL) */
156
157 while (blkCnt > 0U)
158 {
159 /* C = A + B */
160
161 /* Add and store result in destination buffer. */
162 #if defined (ARM_MATH_DSP)
163 *pDst++ = (q15_t) __QADD16(*pSrcA++, *pSrcB++);
164 #else
165 *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ + *pSrcB++), 16);
166 #endif
167
168 /* Decrement loop counter */
169 blkCnt--;
170 }
171
172 }
173 #endif /* defined(ARM_MATH_MVEI) */
174 /**
175 @} end of BasicAdd group
176 */
177