/* ---------------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 15. February 2012 * $Revision: V1.1.0 * * Project: CMSIS DSP Library * Title: arm_q7_to_q15.c * * Description: Converts the elements of the Q7 vector to Q15 vector. * * 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 groupSupport */ /** * @addtogroup q7_to_x * @{ */ /** * @brief Converts the elements of the Q7 vector to Q15 vector. * @param[in] *pSrc points to the Q7 input vector * @param[out] *pDst points to the Q15 output vector * @param[in] blockSize length of the input vector * @return none. * * \par Description: * * The equation used for the conversion process is: * *
* pDst[n] = (q15_t) pSrc[n] << 8; 0 <= n < blockSize. ** */ void arm_q7_to_q15( q7_t * pSrc, q15_t * pDst, uint32_t blockSize) { q7_t *pIn = pSrc; /* Src pointer */ uint32_t blkCnt; /* loop counter */ #ifndef ARM_MATH_CM0 q31_t in; q31_t in1, in2; q31_t out1, out2; /* Run the below code for Cortex-M4 and Cortex-M3 */ /*loop Unrolling */ blkCnt = blockSize >> 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 = (q15_t) A << 8 */ /* convert from q7 to q15 and then store the results in the destination buffer */ in = *__SIMD32(pIn)++; /* rotatate in by 8 and extend two q7_t values to q15_t values */ in1 = __SXTB16(__ROR(in, 8)); /* extend remainig two q7_t values to q15_t values */ in2 = __SXTB16(in); in1 = in1 << 8u; in2 = in2 << 8u; in1 = in1 & 0xFF00FF00; in2 = in2 & 0xFF00FF00; #ifndef ARM_MATH_BIG_ENDIAN out2 = __PKHTB(in1, in2, 16); out1 = __PKHBT(in2, in1, 16); #else out1 = __PKHTB(in1, in2, 16); out2 = __PKHBT(in2, in1, 16); #endif *__SIMD32(pDst)++ = out1; *__SIMD32(pDst)++ = out2; /* Decrement the loop counter */ blkCnt--; } /* If the blockSize is not a multiple of 4, compute any remaining output samples here. ** No loop unrolling is used. */ blkCnt = blockSize % 0x4u; #else /* Run the below code for Cortex-M0 */ /* Loop over blockSize number of values */ blkCnt = blockSize; #endif /* #ifndef ARM_MATH_CM0 */ while(blkCnt > 0u) { /* C = (q15_t) A << 8 */ /* convert from q7 to q15 and then store the results in the destination buffer */ *pDst++ = (q15_t) * pIn++ << 8; /* Decrement the loop counter */ blkCnt--; } } /** * @} end of q7_to_x group */