arm_cmplx_conj_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_conj_q15.c 00009 * 00010 * Description: Q15 complex conjugate. 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_conj_q15( 00053 q15_t * pSrc, 00054 q15_t * pDst, 00055 uint32_t numSamples) 00056 { 00057 uint32_t blkCnt; /* loop counter */ 00058 q31_t in1, in2, in3, in4; /* temporary variables */ 00059 q31_t zero = 0; 00060 00061 /*loop Unrolling */ 00062 blkCnt = numSamples >> 2u; 00063 00064 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00065 ** a second loop below computes the remaining 1 to 3 samples. */ 00066 while(blkCnt > 0u) 00067 { 00068 /* C[0]+jC[1] = A[0]+ j (-1) A[1] */ 00069 /* Calculate Complex Conjugate and then store the results in the destination buffer. */ 00070 /* read real and imaginary inputs at a time */ 00071 in1 = _SIMD32_OFFSET(pSrc); 00072 in2 = _SIMD32_OFFSET(pSrc + 2); 00073 00074 /* exchange real and imaginary, subtract imaginary and add real to zero */ 00075 #ifndef ARM_MATH_BIG_ENDIAN 00076 00077 in1 = __QASX(zero, in1); 00078 00079 #else 00080 00081 in1 = __QSAX(zero, in1); 00082 00083 #endif // #ifndef ARM_MATH_BIG_ENDIAN 00084 00085 /* read real and imaginary inputs at a time */ 00086 in3 = _SIMD32_OFFSET(pSrc + 4); 00087 00088 /* exchange real and imaginary, subtract imaginary and add real to zero */ 00089 #ifndef ARM_MATH_BIG_ENDIAN 00090 00091 in2 = __QASX(zero, in2); 00092 00093 #else 00094 00095 in2 = __QSAX(zero, in2); 00096 00097 #endif // #ifndef ARM_MATH_BIG_ENDIAN 00098 00099 /* read real and imaginary inputs at a time */ 00100 in4 = _SIMD32_OFFSET(pSrc + 6); 00101 00102 /* exchange upper and lower */ 00103 in1 = ((uint32_t)in1 >> 16) | ((uint32_t)in1 << 16); 00104 in2 = ((uint32_t)in2 >> 16) | ((uint32_t)in2 << 16); 00105 00106 /* exchange real and imaginary, subtract imaginary and add real to zero */ 00107 #ifndef ARM_MATH_BIG_ENDIAN 00108 00109 in3 = __QASX(zero, in3); 00110 in4 = __QASX(zero, in4); 00111 00112 #else 00113 00114 in3 = __QSAX(zero, in3); 00115 in4 = __QSAX(zero, in4); 00116 00117 #endif // #ifndef ARM_MATH_BIG_ENDIAN 00118 00119 /* store result to destination buffer both real and imaginay at a time */ 00120 _SIMD32_OFFSET(pDst) = in1; 00121 _SIMD32_OFFSET(pDst + 2) = in2; 00122 00123 /* exchange upper and lower */ 00124 in3 = ((uint32_t)in3 >> 16) | ((uint32_t)in3 << 16); 00125 in4 = ((uint32_t)in4 >> 16) | ((uint32_t)in4 << 16); 00126 00127 /* store result to destination buffer both real and imaginay at a time */ 00128 _SIMD32_OFFSET(pDst + 4) = in3; 00129 00130 /* increment source pointer by 8 to process next samples */ 00131 pSrc += 8u; 00132 00133 /* store result to destination buffer both real and imaginay at a time */ 00134 _SIMD32_OFFSET(pDst + 6) = in4; 00135 /* increment destination pointer by 8 to process next samples */ 00136 pDst += 8u; 00137 00138 /* Decrement the loop counter */ 00139 blkCnt--; 00140 } 00141 00142 /* If the numSamples is not a multiple of 4, compute any remaining output samples here. 00143 ** No loop unrolling is used. */ 00144 blkCnt = numSamples % 0x4u; 00145 00146 while(blkCnt > 0u) 00147 { 00148 /* C[0]+jC[1] = A[0]+ j (-1) A[1] */ 00149 /* Calculate Complex Conjugate and then store the results in the destination buffer. */ 00150 *pDst++ = *pSrc++; 00151 #ifdef CCS 00152 *pDst++ = __SSATA(-*pSrc++, 0, 16); 00153 #else 00154 *pDst++ = __SSAT(-*pSrc++, 16); 00155 #endif 00156 00157 /* Decrement the loop counter */ 00158 blkCnt--; 00159 } 00160 } 00161
