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git.gir.st - tmk_keyboard.git/blob - tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_squared_q15.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_mag_squared_q15.c
10 * Description: Q15 complex magnitude squared.
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 cmplx_mag_squared
53 * @brief Q15 complex magnitude squared
54 * @param *pSrc points to the complex input vector
55 * @param *pDst points to the real output vector
56 * @param numSamples number of complex samples in the input vector
59 * <b>Scaling and Overflow Behavior:</b>
61 * The function implements 1.15 by 1.15 multiplications and finally output is converted into 3.13 format.
64 void arm_cmplx_mag_squared_q15(
69 q31_t acc0
, acc1
; /* Accumulators */
71 #ifndef ARM_MATH_CM0_FAMILY
73 /* Run the below code for Cortex-M4 and Cortex-M3 */
74 uint32_t blkCnt
; /* loop counter */
75 q31_t in1
, in2
, in3
, in4
;
79 blkCnt
= numSamples
>> 2u;
81 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
82 ** a second loop below computes the remaining 1 to 3 samples. */
85 /* C[0] = (A[0] * A[0] + A[1] * A[1]) */
86 in1
= *__SIMD32(pSrc
)++;
87 in2
= *__SIMD32(pSrc
)++;
88 in3
= *__SIMD32(pSrc
)++;
89 in4
= *__SIMD32(pSrc
)++;
91 acc0
= __SMUAD(in1
, in1
);
92 acc1
= __SMUAD(in2
, in2
);
93 acc2
= __SMUAD(in3
, in3
);
94 acc3
= __SMUAD(in4
, in4
);
96 /* store the result in 3.13 format in the destination buffer. */
97 *pDst
++ = (q15_t
) (acc0
>> 17);
98 *pDst
++ = (q15_t
) (acc1
>> 17);
99 *pDst
++ = (q15_t
) (acc2
>> 17);
100 *pDst
++ = (q15_t
) (acc3
>> 17);
102 /* Decrement the loop counter */
106 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
107 ** No loop unrolling is used. */
108 blkCnt
= numSamples
% 0x4u
;
112 /* C[0] = (A[0] * A[0] + A[1] * A[1]) */
113 in1
= *__SIMD32(pSrc
)++;
114 acc0
= __SMUAD(in1
, in1
);
116 /* store the result in 3.13 format in the destination buffer. */
117 *pDst
++ = (q15_t
) (acc0
>> 17);
119 /* Decrement the loop counter */
125 /* Run the below code for Cortex-M0 */
126 q15_t real
, imag
; /* Temporary variables to store real and imaginary values */
128 while(numSamples
> 0u)
130 /* out = ((real * real) + (imag * imag)) */
133 acc0
= (real
* real
);
134 acc1
= (imag
* imag
);
135 /* store the result in 3.13 format in the destination buffer. */
136 *pDst
++ = (q15_t
) (((q63_t
) acc0
+ acc1
) >> 17);
138 /* Decrement the loop counter */
142 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
147 * @} end of cmplx_mag_squared group