1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_cmplx_mult_real_q31.c
4 * Description: Q31 complex by real 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/complex_math_functions.h"
30
31 /**
32 @ingroup groupCmplxMath
33 */
34
35 /**
36 @addtogroup CmplxByRealMult
37 @{
38 */
39
40 /**
41 @brief Q31 complex-by-real multiplication.
42 @param[in] pSrcCmplx points to complex input vector
43 @param[in] pSrcReal points to real input vector
44 @param[out] pCmplxDst points to complex output vector
45 @param[in] numSamples 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 Q31 range[0x80000000 0x7FFFFFFF] are saturated.
51 */
52
53 #if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
arm_cmplx_mult_real_q31(const q31_t * pSrcCmplx,const q31_t * pSrcReal,q31_t * pCmplxDst,uint32_t numSamples)54 void arm_cmplx_mult_real_q31(
55 const q31_t * pSrcCmplx,
56 const q31_t * pSrcReal,
57 q31_t * pCmplxDst,
58 uint32_t numSamples)
59 {
60
61 static const uint32_t stride_cmplx_x_real_32[4] = {
62 0, 0, 1, 1
63 };
64 q31x4_t rVec;
65 q31x4_t cmplxVec;
66 q31x4_t dstVec;
67 uint32x4_t strideVec;
68 uint32_t blockSizeC = numSamples * CMPLX_DIM; /* loop counters */
69 uint32_t blkCnt;
70 q31_t in;
71
72 /*
73 * stride vector for pairs of real generation
74 */
75 strideVec = vld1q(stride_cmplx_x_real_32);
76
77 /* Compute 4 complex outputs at a time */
78 blkCnt = blockSizeC >> 2;
79 while (blkCnt > 0U)
80 {
81 cmplxVec = vld1q(pSrcCmplx);
82 rVec = vldrwq_gather_shifted_offset_s32(pSrcReal, strideVec);
83 dstVec = vqdmulhq(cmplxVec, rVec);
84 vst1q(pCmplxDst, dstVec);
85
86 pSrcReal += 2;
87 pSrcCmplx += 4;
88 pCmplxDst += 4;
89 blkCnt --;
90 }
91
92 blkCnt = (blockSizeC & 3) >> 1;
93 while (blkCnt > 0U)
94 {
95 /* C[2 * i ] = A[2 * i ] * B[i]. */
96 /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
97
98 in = *pSrcReal++;
99 /* store saturated result in 1.31 format to destination buffer */
100 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
101 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
102
103 /* Decrement loop counter */
104 blkCnt--;
105 }
106 }
107 #else
arm_cmplx_mult_real_q31(const q31_t * pSrcCmplx,const q31_t * pSrcReal,q31_t * pCmplxDst,uint32_t numSamples)108 void arm_cmplx_mult_real_q31(
109 const q31_t * pSrcCmplx,
110 const q31_t * pSrcReal,
111 q31_t * pCmplxDst,
112 uint32_t numSamples)
113 {
114 uint32_t blkCnt; /* Loop counter */
115 q31_t in; /* Temporary variable */
116
117 #if defined (ARM_MATH_LOOPUNROLL)
118
119 /* Loop unrolling: Compute 4 outputs at a time */
120 blkCnt = numSamples >> 2U;
121
122 while (blkCnt > 0U)
123 {
124 /* C[2 * i ] = A[2 * i ] * B[i]. */
125 /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
126
127 in = *pSrcReal++;
128 #if defined (ARM_MATH_DSP)
129 /* store saturated result in 1.31 format to destination buffer */
130 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
131 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
132 #else
133 /* store result in destination buffer. */
134 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
135 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
136 #endif
137
138 in = *pSrcReal++;
139 #if defined (ARM_MATH_DSP)
140 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
141 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
142 #else
143 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
144 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
145 #endif
146
147 in = *pSrcReal++;
148 #if defined (ARM_MATH_DSP)
149 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
150 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
151 #else
152 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
153 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
154 #endif
155
156 in = *pSrcReal++;
157 #if defined (ARM_MATH_DSP)
158 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
159 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
160 #else
161 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
162 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
163 #endif
164
165 /* Decrement loop counter */
166 blkCnt--;
167 }
168
169 /* Loop unrolling: Compute remaining outputs */
170 blkCnt = numSamples % 0x4U;
171
172 #else
173
174 /* Initialize blkCnt with number of samples */
175 blkCnt = numSamples;
176
177 #endif /* #if defined (ARM_MATH_LOOPUNROLL) */
178
179 while (blkCnt > 0U)
180 {
181 /* C[2 * i ] = A[2 * i ] * B[i]. */
182 /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
183
184 in = *pSrcReal++;
185 #if defined (ARM_MATH_DSP)
186 /* store saturated result in 1.31 format to destination buffer */
187 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
188 *pCmplxDst++ = (__SSAT((q31_t) (((q63_t) *pSrcCmplx++ * in) >> 32), 31) << 1);
189 #else
190 /* store result in destination buffer. */
191 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
192 *pCmplxDst++ = (q31_t) clip_q63_to_q31(((q63_t) *pSrcCmplx++ * in) >> 31);
193 #endif
194
195 /* Decrement loop counter */
196 blkCnt--;
197 }
198
199 }
200 #endif /* defined(ARM_MATH_MVEI) */
201
202 /**
203 @} end of CmplxByRealMult group
204 */
205
