arm_cmplx_mag_q15.c
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00001 /* ---------------------------------------------------------------------- 00002 * Copyright (C) 2011 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 15. December 2011 00005 * $Revision: V2.0.0 00006 * 00007 * Project: Cortex-R DSP Library 00008 * Title: arm_cmplx_mag_q15.c 00009 * 00010 * Description: Q15 complex magnitude. 00011 * 00012 * Target Processor: Cortex-R4/R5 00013 * 00014 * Version 1.0.0 2011/03/08 00015 * Alpha release. 00016 * 00017 * Version 1.0.1 2011/09/30 00018 * Beta release. 00019 * 00020 * Version 2.0.0 2011/12/15 00021 * Final release. 00022 * 00023 * ---------------------------------------------------------------------------- */ 00024 #include "arm_math.h" 00025 00052 void arm_cmplx_mag_q15( 00053 q15_t * pSrc, 00054 q15_t * pDst, 00055 uint32_t numSamples) 00056 { 00057 q15_t real, imag; /* Temporary variables to hold input values */ 00058 q31_t in1, in2, in3, in4; /* Temporary variables to hold input values */ 00059 q31_t acc1, acc2, acc3, acc4; /* Temporary variables to hold power of values */ 00060 q15_t out1, out2, out3, out4; /* Temporary variables */ 00061 uint32_t blkCnt; /* loop counter */ 00062 00063 00064 /*loop Unrolling */ 00065 blkCnt = numSamples >> 2u; 00066 00067 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00068 ** a second loop below computes the remaining 1 to 3 samples. */ 00069 while(blkCnt > 0u) 00070 { 00071 /* read real and imaginary values */ 00072 in1 = _SIMD32_OFFSET(pSrc); 00073 in2 = _SIMD32_OFFSET(pSrc + 2); 00074 in3 = _SIMD32_OFFSET(pSrc + 4); 00075 in4 = _SIMD32_OFFSET(pSrc + 6); 00076 00077 /* calculate power of real and imaginary values and accumulate */ 00078 acc1 = __SMUAD(in1, in1); 00079 acc2 = __SMUAD(in2, in2); 00080 acc3 = __SMUAD(in3, in3); 00081 acc4 = __SMUAD(in4, in4); 00082 00083 /* shift the output to get the resutl in 3.13 format */ 00084 out1 = (q15_t)(acc1 >> 17); 00085 out2 = (q15_t)(acc2 >> 17); 00086 out3 = (q15_t)(acc3 >> 17); 00087 out4 = (q15_t)(acc4 >> 17); 00088 00089 /* calculate squrate of output value in 2.14 format */ 00090 arm_sqrt_q15(out1, &pDst[0]); 00091 arm_sqrt_q15(out2, &pDst[1]); 00092 arm_sqrt_q15(out3, &pDst[2]); 00093 arm_sqrt_q15(out4, &pDst[3]); 00094 00095 /* increment pointer to process next samples */ 00096 pSrc += 8u; 00097 pDst += 4u; 00098 00099 /* Decrement the loop counter */ 00100 blkCnt--; 00101 } 00102 00103 /* If the numSamples is not a multiple of 4, compute any remaining output samples here. 00104 ** No loop unrolling is used. */ 00105 blkCnt = numSamples % 0x4u; 00106 00107 while(blkCnt > 0u) 00108 { 00109 /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */ 00110 real = *pSrc++; 00111 imag = *pSrc++; 00112 acc1 = __SMUAD(real, real); 00113 acc2 = __SMUAD(imag, imag); 00114 /* store the result in 2.14 format in the destination buffer. */ 00115 arm_sqrt_q15((q15_t) (((q63_t) acc1 + acc2) >> 17), pDst++); 00116 00117 /* Decrement the loop counter */ 00118 blkCnt--; 00119 } 00120 } 00121
