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Diff: cmsis_dsp/ComplexMathFunctions/arm_cmplx_conj_q15.c
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/ComplexMathFunctions/arm_cmplx_conj_q15.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,153 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_cmplx_conj_q15.c +* +* Description: Q15 complex conjugate. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* Version 1.0.3 2010/11/29 +* Re-organized the CMSIS folders and updated documentation. +* +* Version 1.0.2 2010/11/11 +* Documentation updated. +* +* Version 1.0.1 2010/10/05 +* Production release and review comments incorporated. +* +* Version 1.0.0 2010/09/20 +* Production release and review comments incorporated. +* ---------------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupCmplxMath + */ + +/** + * @addtogroup cmplx_conj + * @{ + */ + +/** + * @brief Q15 complex conjugate. + * @param *pSrc points to the input vector + * @param *pDst points to the output vector + * @param numSamples number of complex samples in each vector + * @return none. + * + * <b>Scaling and Overflow Behavior:</b> + * \par + * The function uses saturating arithmetic. + * The Q15 value -1 (0x8000) will be saturated to the maximum allowable positive value 0x7FFF. + */ + +void arm_cmplx_conj_q15( + q15_t * pSrc, + q15_t * pDst, + uint32_t numSamples) +{ + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + uint32_t blkCnt; /* loop counter */ + q31_t in1, in2, in3, in4; + q31_t zero = 0; + + /*loop Unrolling */ + blkCnt = numSamples >> 2u; + + /* First part of the processing with loop unrolling. Compute 4 outputs at a time. + ** a second loop below computes the remaining 1 to 3 samples. */ + while(blkCnt > 0u) + { + /* C[0]+jC[1] = A[0]+ j (-1) A[1] */ + /* Calculate Complex Conjugate and then store the results in the destination buffer. */ + in1 = *__SIMD32(pSrc)++; + in2 = *__SIMD32(pSrc)++; + in3 = *__SIMD32(pSrc)++; + in4 = *__SIMD32(pSrc)++; + +#ifndef ARM_MATH_BIG_ENDIAN + + in1 = __QASX(zero, in1); + in2 = __QASX(zero, in2); + in3 = __QASX(zero, in3); + in4 = __QASX(zero, in4); + +#else + + in1 = __QSAX(zero, in1); + in2 = __QSAX(zero, in2); + in3 = __QSAX(zero, in3); + in4 = __QSAX(zero, in4); + +#endif // #ifndef ARM_MATH_BIG_ENDIAN + + in1 = ((uint32_t) in1 >> 16) | ((uint32_t) in1 << 16); + in2 = ((uint32_t) in2 >> 16) | ((uint32_t) in2 << 16); + in3 = ((uint32_t) in3 >> 16) | ((uint32_t) in3 << 16); + in4 = ((uint32_t) in4 >> 16) | ((uint32_t) in4 << 16); + + *__SIMD32(pDst)++ = in1; + *__SIMD32(pDst)++ = in2; + *__SIMD32(pDst)++ = in3; + *__SIMD32(pDst)++ = in4; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* If the numSamples is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = numSamples % 0x4u; + + while(blkCnt > 0u) + { + /* C[0]+jC[1] = A[0]+ j (-1) A[1] */ + /* Calculate Complex Conjugate and then store the results in the destination buffer. */ + *pDst++ = *pSrc++; + *pDst++ = __SSAT(-*pSrc++, 16); + + /* Decrement the loop counter */ + blkCnt--; + } + +#else + + q15_t in; + + /* Run the below code for Cortex-M0 */ + + while(numSamples > 0u) + { + /* realOut + j (imagOut) = realIn+ j (-1) imagIn */ + /* Calculate Complex Conjugate and then store the results in the destination buffer. */ + *pDst++ = *pSrc++; + in = *pSrc++; + *pDst++ = (in == (q15_t) 0x8000) ? 0x7fff : -in; + + /* Decrement the loop counter */ + numSamples--; + } + +#endif /* #ifndef ARM_MATH_CM0 */ + +} + +/** + * @} end of cmplx_conj group + */