1 /* ----------------------------------------------------------------------
2  * Project:      CMSIS DSP Library
3  * Title:        arm_add_q31.c
4  * Description:  Q31 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         Q31 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 
47   @par           Scaling and Overflow Behavior
48                    The function uses saturating arithmetic.
49                    Results outside of the allowable Q31 range [0x80000000 0x7FFFFFFF] are saturated.
50  */
51 
52 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
53 
54 #include "arm_helium_utils.h"
55 
arm_add_q31(const q31_t * pSrcA,const q31_t * pSrcB,q31_t * pDst,uint32_t blockSize)56 void arm_add_q31(
57   const q31_t * pSrcA,
58   const q31_t * pSrcB,
59         q31_t * pDst,
60         uint32_t blockSize)
61 {
62     uint32_t blkCnt;
63     q31x4_t vecA;
64     q31x4_t vecB;
65 
66     /* Compute 4 outputs at a time */
67     blkCnt = blockSize >> 2;
68     while (blkCnt > 0U)
69     {
70         /*
71          * C = A + B
72          * Add and then store the results in the destination buffer.
73          */
74         vecA = vld1q(pSrcA);
75         vecB = vld1q(pSrcB);
76         vst1q(pDst, vqaddq(vecA, vecB));
77         /*
78          * Decrement the blockSize loop counter
79          */
80         blkCnt--;
81         /*
82          * advance vector source and destination pointers
83          */
84         pSrcA  += 4;
85         pSrcB  += 4;
86         pDst   += 4;
87     }
88     /*
89      * tail
90      */
91     blkCnt = blockSize & 3;
92     if (blkCnt > 0U)
93     {
94         mve_pred16_t p0 = vctp32q(blkCnt);
95         vecA = vld1q(pSrcA);
96         vecB = vld1q(pSrcB);
97         vstrwq_p(pDst, vqaddq(vecA, vecB), p0);
98     }
99 }
100 
101 #else
arm_add_q31(const q31_t * pSrcA,const q31_t * pSrcB,q31_t * pDst,uint32_t blockSize)102 void arm_add_q31(
103   const q31_t * pSrcA,
104   const q31_t * pSrcB,
105         q31_t * pDst,
106         uint32_t blockSize)
107 {
108         uint32_t blkCnt;                               /* Loop counter */
109 
110 #if defined (ARM_MATH_LOOPUNROLL)
111 
112   /* Loop unrolling: Compute 4 outputs at a time */
113   blkCnt = blockSize >> 2U;
114 
115   while (blkCnt > 0U)
116   {
117     /* C = A + B */
118 
119     /* Add and store result in destination buffer. */
120     *pDst++ = __QADD(*pSrcA++, *pSrcB++);
121 
122     *pDst++ = __QADD(*pSrcA++, *pSrcB++);
123 
124     *pDst++ = __QADD(*pSrcA++, *pSrcB++);
125 
126     *pDst++ = __QADD(*pSrcA++, *pSrcB++);
127 
128     /* Decrement loop counter */
129     blkCnt--;
130   }
131 
132   /* Loop unrolling: Compute remaining outputs */
133   blkCnt = blockSize % 0x4U;
134 
135 #else
136 
137   /* Initialize blkCnt with number of samples */
138   blkCnt = blockSize;
139 
140 #endif /* #if defined (ARM_MATH_LOOPUNROLL) */
141 
142   while (blkCnt > 0U)
143   {
144     /* C = A + B */
145 
146     /* Add and store result in destination buffer. */
147     *pDst++ = __QADD(*pSrcA++, *pSrcB++);
148 
149     /* Decrement loop counter */
150     blkCnt--;
151   }
152 
153 }
154 
155 #endif /* defined(ARM_MATH_MVEI) */
156 /**
157   @} end of BasicAdd group
158  */
159