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git.gir.st - tmk_keyboard.git/blob - tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mult_real_q31.c
1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
4 * $Date: 17. January 2013
7 * Project: CMSIS DSP Library
8 * Title: arm_cmplx_mult_real_q31.c
10 * Description: Q31 complex by real multiplication
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
17 * - Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * - Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in
21 * the documentation and/or other materials provided with the
23 * - Neither the name of ARM LIMITED nor the names of its contributors
24 * may be used to endorse or promote products derived from this
25 * software without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 * -------------------------------------------------------------------- */
44 * @ingroup groupCmplxMath
48 * @addtogroup CmplxByRealMult
54 * @brief Q31 complex-by-real multiplication
55 * @param[in] *pSrcCmplx points to the complex input vector
56 * @param[in] *pSrcReal points to the real input vector
57 * @param[out] *pCmplxDst points to the complex output vector
58 * @param[in] numSamples number of samples in each vector
61 * <b>Scaling and Overflow Behavior:</b>
63 * The function uses saturating arithmetic.
64 * Results outside of the allowable Q31 range[0x80000000 0x7FFFFFFF] will be saturated.
67 void arm_cmplx_mult_real_q31(
73 q31_t inA1
; /* Temporary variable to store input value */
75 #ifndef ARM_MATH_CM0_FAMILY
77 /* Run the below code for Cortex-M4 and Cortex-M3 */
78 uint32_t blkCnt
; /* loop counters */
79 q31_t inA2
, inA3
, inA4
; /* Temporary variables to hold input data */
80 q31_t inB1
, inB2
; /* Temporary variabels to hold input data */
81 q31_t out1
, out2
, out3
, out4
; /* Temporary variables to hold output data */
84 blkCnt
= numSamples
>> 2u;
86 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
87 ** a second loop below computes the remaining 1 to 3 samples. */
90 /* C[2 * i] = A[2 * i] * B[i]. */
91 /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
92 /* read real input from complex input buffer */
95 /* read input from real input bufer */
98 /* read imaginary input from complex input buffer */
102 /* multiply complex input with real input */
103 out1
= ((q63_t
) inA1
* inB1
) >> 32;
104 out2
= ((q63_t
) inA2
* inB1
) >> 32;
105 out3
= ((q63_t
) inA3
* inB2
) >> 32;
106 out4
= ((q63_t
) inA4
* inB2
) >> 32;
108 /* sature the result */
109 out1
= __SSAT(out1
, 31);
110 out2
= __SSAT(out2
, 31);
111 out3
= __SSAT(out3
, 31);
112 out4
= __SSAT(out4
, 31);
114 /* get result in 1.31 format */
120 /* store the result to destination buffer */
126 /* read real input from complex input buffer */
129 /* read input from real input bufer */
132 /* read imaginary input from complex input buffer */
136 /* multiply complex input with real input */
137 out1
= ((q63_t
) inA1
* inB1
) >> 32;
138 out2
= ((q63_t
) inA2
* inB1
) >> 32;
139 out3
= ((q63_t
) inA3
* inB2
) >> 32;
140 out4
= ((q63_t
) inA4
* inB2
) >> 32;
142 /* sature the result */
143 out1
= __SSAT(out1
, 31);
144 out2
= __SSAT(out2
, 31);
145 out3
= __SSAT(out3
, 31);
146 out4
= __SSAT(out4
, 31);
148 /* get result in 1.31 format */
154 /* store the result to destination buffer */
160 /* Decrement the numSamples loop counter */
164 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
165 ** No loop unrolling is used. */
166 blkCnt
= numSamples
% 0x4u
;
170 /* C[2 * i] = A[2 * i] * B[i]. */
171 /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
172 /* read real input from complex input buffer */
175 /* read input from real input bufer */
178 /* multiply complex input with real input */
179 out1
= ((q63_t
) inA1
* inB1
) >> 32;
180 out2
= ((q63_t
) inA2
* inB1
) >> 32;
182 /* sature the result */
183 out1
= __SSAT(out1
, 31);
184 out2
= __SSAT(out2
, 31);
186 /* get result in 1.31 format */
190 /* store the result to destination buffer */
194 /* Decrement the numSamples loop counter */
200 /* Run the below code for Cortex-M0 */
202 while(numSamples
> 0u)
204 /* realOut = realA * realB. */
205 /* imagReal = imagA * realB. */
207 /* store the result in the destination buffer. */
209 (q31_t
) clip_q63_to_q31(((q63_t
) * pSrcCmplx
++ * inA1
) >> 31);
211 (q31_t
) clip_q63_to_q31(((q63_t
) * pSrcCmplx
++ * inA1
) >> 31);
213 /* Decrement the numSamples loop counter */
217 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
222 * @} end of CmplxByRealMult group