Laxmi Kant Tiwari / mbed-dsp

CMSIS DSP Lib

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cmsis_dsp/ComplexMathFunctions/arm_cmplx_conj_q15.c@3:7a284390b0ce, 2013-11-08 (annotated)

Committer:
mbed_official
Date:
Fri Nov 08 13:45:10 2013 +0000
Revision:
3:7a284390b0ce
Parent:
2:da51fb522205 
Synchronized with git revision e69956aba2f68a2a26ac26b051f8d349deaa1ce8

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
mbed_official 3:7a284390b0ce 2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
mbed_official 3:7a284390b0ce 4 * $Date: 17. January 2013
mbed_official 3:7a284390b0ce 5 * $Revision: V1.4.1
emilmont 1:fdd22bb7aa52 6 *
emilmont 2:da51fb522205 7 * Project: CMSIS DSP Library
emilmont 2:da51fb522205 8 * Title: arm_cmplx_conj_q15.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 2:da51fb522205 10 * Description: Q15 complex conjugate.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
mbed_official 3:7a284390b0ce 14 * Redistribution and use in source and binary forms, with or without
mbed_official 3:7a284390b0ce 15 * modification, are permitted provided that the following conditions
mbed_official 3:7a284390b0ce 16 * are met:
mbed_official 3:7a284390b0ce 17 * - Redistributions of source code must retain the above copyright
mbed_official 3:7a284390b0ce 18 * notice, this list of conditions and the following disclaimer.
mbed_official 3:7a284390b0ce 19 * - Redistributions in binary form must reproduce the above copyright
mbed_official 3:7a284390b0ce 20 * notice, this list of conditions and the following disclaimer in
mbed_official 3:7a284390b0ce 21 * the documentation and/or other materials provided with the
mbed_official 3:7a284390b0ce 22 * distribution.
mbed_official 3:7a284390b0ce 23 * - Neither the name of ARM LIMITED nor the names of its contributors
mbed_official 3:7a284390b0ce 24 * may be used to endorse or promote products derived from this
mbed_official 3:7a284390b0ce 25 * software without specific prior written permission.
mbed_official 3:7a284390b0ce 26 *
mbed_official 3:7a284390b0ce 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
mbed_official 3:7a284390b0ce 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
mbed_official 3:7a284390b0ce 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
mbed_official 3:7a284390b0ce 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
mbed_official 3:7a284390b0ce 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
mbed_official 3:7a284390b0ce 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
mbed_official 3:7a284390b0ce 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
mbed_official 3:7a284390b0ce 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
mbed_official 3:7a284390b0ce 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
mbed_official 3:7a284390b0ce 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
mbed_official 3:7a284390b0ce 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
mbed_official 3:7a284390b0ce 38 * POSSIBILITY OF SUCH DAMAGE.
emilmont 1:fdd22bb7aa52 39 * ---------------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 40
emilmont 1:fdd22bb7aa52 41 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 42
emilmont 1:fdd22bb7aa52 43 /**
emilmont 1:fdd22bb7aa52 44 * @ingroup groupCmplxMath
emilmont 1:fdd22bb7aa52 45 */
emilmont 1:fdd22bb7aa52 46
emilmont 1:fdd22bb7aa52 47 /**
emilmont 1:fdd22bb7aa52 48 * @addtogroup cmplx_conj
emilmont 1:fdd22bb7aa52 49 * @{
emilmont 1:fdd22bb7aa52 50 */
emilmont 1:fdd22bb7aa52 51
emilmont 1:fdd22bb7aa52 52 /**
emilmont 1:fdd22bb7aa52 53 * @brief Q15 complex conjugate.
emilmont 1:fdd22bb7aa52 54 * @param *pSrc points to the input vector
emilmont 1:fdd22bb7aa52 55 * @param *pDst points to the output vector
emilmont 1:fdd22bb7aa52 56 * @param numSamples number of complex samples in each vector
emilmont 1:fdd22bb7aa52 57 * @return none.
emilmont 1:fdd22bb7aa52 58 *
emilmont 1:fdd22bb7aa52 59 * <b>Scaling and Overflow Behavior:</b>
emilmont 1:fdd22bb7aa52 60 * \par
emilmont 1:fdd22bb7aa52 61 * The function uses saturating arithmetic.
emilmont 1:fdd22bb7aa52 62 * The Q15 value -1 (0x8000) will be saturated to the maximum allowable positive value 0x7FFF.
emilmont 1:fdd22bb7aa52 63 */
emilmont 1:fdd22bb7aa52 64
emilmont 1:fdd22bb7aa52 65 void arm_cmplx_conj_q15(
emilmont 1:fdd22bb7aa52 66 q15_t * pSrc,
emilmont 1:fdd22bb7aa52 67 q15_t * pDst,
emilmont 1:fdd22bb7aa52 68 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 69 {
emilmont 1:fdd22bb7aa52 70
mbed_official 3:7a284390b0ce 71 #ifndef ARM_MATH_CM0_FAMILY
emilmont 1:fdd22bb7aa52 72
emilmont 1:fdd22bb7aa52 73 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 74 uint32_t blkCnt; /* loop counter */
emilmont 1:fdd22bb7aa52 75 q31_t in1, in2, in3, in4;
emilmont 1:fdd22bb7aa52 76 q31_t zero = 0;
emilmont 1:fdd22bb7aa52 77
emilmont 1:fdd22bb7aa52 78 /*loop Unrolling */
emilmont 1:fdd22bb7aa52 79 blkCnt = numSamples >> 2u;
emilmont 1:fdd22bb7aa52 80
emilmont 1:fdd22bb7aa52 81 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
emilmont 1:fdd22bb7aa52 82 ** a second loop below computes the remaining 1 to 3 samples. */
emilmont 1:fdd22bb7aa52 83 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 84 {
emilmont 1:fdd22bb7aa52 85 /* C[0]+jC[1] = A[0]+ j (-1) A[1] */
emilmont 1:fdd22bb7aa52 86 /* Calculate Complex Conjugate and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 87 in1 = *__SIMD32(pSrc)++;
emilmont 1:fdd22bb7aa52 88 in2 = *__SIMD32(pSrc)++;
emilmont 1:fdd22bb7aa52 89 in3 = *__SIMD32(pSrc)++;
emilmont 1:fdd22bb7aa52 90 in4 = *__SIMD32(pSrc)++;
emilmont 1:fdd22bb7aa52 91
emilmont 1:fdd22bb7aa52 92 #ifndef ARM_MATH_BIG_ENDIAN
emilmont 1:fdd22bb7aa52 93
emilmont 1:fdd22bb7aa52 94 in1 = __QASX(zero, in1);
emilmont 1:fdd22bb7aa52 95 in2 = __QASX(zero, in2);
emilmont 1:fdd22bb7aa52 96 in3 = __QASX(zero, in3);
emilmont 1:fdd22bb7aa52 97 in4 = __QASX(zero, in4);
emilmont 1:fdd22bb7aa52 98
emilmont 1:fdd22bb7aa52 99 #else
emilmont 1:fdd22bb7aa52 100
emilmont 1:fdd22bb7aa52 101 in1 = __QSAX(zero, in1);
emilmont 1:fdd22bb7aa52 102 in2 = __QSAX(zero, in2);
emilmont 1:fdd22bb7aa52 103 in3 = __QSAX(zero, in3);
emilmont 1:fdd22bb7aa52 104 in4 = __QSAX(zero, in4);
emilmont 1:fdd22bb7aa52 105
emilmont 1:fdd22bb7aa52 106 #endif // #ifndef ARM_MATH_BIG_ENDIAN
emilmont 1:fdd22bb7aa52 107
emilmont 1:fdd22bb7aa52 108 in1 = ((uint32_t) in1 >> 16) | ((uint32_t) in1 << 16);
emilmont 1:fdd22bb7aa52 109 in2 = ((uint32_t) in2 >> 16) | ((uint32_t) in2 << 16);
emilmont 1:fdd22bb7aa52 110 in3 = ((uint32_t) in3 >> 16) | ((uint32_t) in3 << 16);
emilmont 1:fdd22bb7aa52 111 in4 = ((uint32_t) in4 >> 16) | ((uint32_t) in4 << 16);
emilmont 1:fdd22bb7aa52 112
emilmont 1:fdd22bb7aa52 113 *__SIMD32(pDst)++ = in1;
emilmont 1:fdd22bb7aa52 114 *__SIMD32(pDst)++ = in2;
emilmont 1:fdd22bb7aa52 115 *__SIMD32(pDst)++ = in3;
emilmont 1:fdd22bb7aa52 116 *__SIMD32(pDst)++ = in4;
emilmont 1:fdd22bb7aa52 117
emilmont 1:fdd22bb7aa52 118 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 119 blkCnt--;
emilmont 1:fdd22bb7aa52 120 }
emilmont 1:fdd22bb7aa52 121
emilmont 1:fdd22bb7aa52 122 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
emilmont 1:fdd22bb7aa52 123 ** No loop unrolling is used. */
emilmont 1:fdd22bb7aa52 124 blkCnt = numSamples % 0x4u;
emilmont 1:fdd22bb7aa52 125
emilmont 1:fdd22bb7aa52 126 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 127 {
emilmont 1:fdd22bb7aa52 128 /* C[0]+jC[1] = A[0]+ j (-1) A[1] */
emilmont 1:fdd22bb7aa52 129 /* Calculate Complex Conjugate and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 130 *pDst++ = *pSrc++;
emilmont 1:fdd22bb7aa52 131 *pDst++ = __SSAT(-*pSrc++, 16);
emilmont 1:fdd22bb7aa52 132
emilmont 1:fdd22bb7aa52 133 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 134 blkCnt--;
emilmont 1:fdd22bb7aa52 135 }
emilmont 1:fdd22bb7aa52 136
emilmont 1:fdd22bb7aa52 137 #else
emilmont 1:fdd22bb7aa52 138
emilmont 1:fdd22bb7aa52 139 q15_t in;
emilmont 1:fdd22bb7aa52 140
emilmont 1:fdd22bb7aa52 141 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 142
emilmont 1:fdd22bb7aa52 143 while(numSamples > 0u)
emilmont 1:fdd22bb7aa52 144 {
emilmont 1:fdd22bb7aa52 145 /* realOut + j (imagOut) = realIn+ j (-1) imagIn */
emilmont 1:fdd22bb7aa52 146 /* Calculate Complex Conjugate and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 147 *pDst++ = *pSrc++;
emilmont 1:fdd22bb7aa52 148 in = *pSrc++;
emilmont 1:fdd22bb7aa52 149 *pDst++ = (in == (q15_t) 0x8000) ? 0x7fff : -in;
emilmont 1:fdd22bb7aa52 150
emilmont 1:fdd22bb7aa52 151 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 152 numSamples--;
emilmont 1:fdd22bb7aa52 153 }
emilmont 1:fdd22bb7aa52 154
mbed_official 3:7a284390b0ce 155 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
emilmont 1:fdd22bb7aa52 156
emilmont 1:fdd22bb7aa52 157 }
emilmont 1:fdd22bb7aa52 158
emilmont 1:fdd22bb7aa52 159 /**
emilmont 1:fdd22bb7aa52 160 * @} end of cmplx_conj group
emilmont 1:fdd22bb7aa52 161 */