/* ---------------------------------------------------------------------- * Copyright (C) 2010-2013 ARM Limited. All rights reserved. * * $Date: 17. January 2013 * $Revision: V1.4.1 * * Project: CMSIS DSP Library * Title: arm_cmplx_mult_real_q15.c * * Description: Q15 complex by real multiplication * * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * - Neither the name of ARM LIMITED nor the names of its contributors * may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * -------------------------------------------------------------------- */ #include "arm_math.h" /** * @ingroup groupCmplxMath */ /** * @addtogroup CmplxByRealMult * @{ */ /** * @brief Q15 complex-by-real multiplication * @param[in] *pSrcCmplx points to the complex input vector * @param[in] *pSrcReal points to the real input vector * @param[out] *pCmplxDst points to the complex output vector * @param[in] numSamples number of samples in each vector * @return none. * * Scaling and Overflow Behavior: * \par * The function uses saturating arithmetic. * Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated. */ void arm_cmplx_mult_real_q15( q15_t * pSrcCmplx, q15_t * pSrcReal, q15_t * pCmplxDst, uint32_t numSamples) { q15_t in; /* Temporary variable to store input value */ #ifndef ARM_MATH_CM0_FAMILY /* Run the below code for Cortex-M4 and Cortex-M3 */ uint32_t blkCnt; /* loop counters */ q31_t inA1, inA2; /* Temporary variables to hold input data */ q31_t inB1; /* Temporary variables to hold input data */ q15_t out1, out2, out3, out4; /* Temporary variables to hold output data */ q31_t mul1, mul2, mul3, mul4; /* Temporary variables to hold intermediate data */ /* 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[2 * i] = A[2 * i] * B[i]. */ /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */ /* read complex number both real and imaginary from complex input buffer */ inA1 = *__SIMD32(pSrcCmplx)++; /* read two real values at a time from real input buffer */ inB1 = *__SIMD32(pSrcReal)++; /* read complex number both real and imaginary from complex input buffer */ inA2 = *__SIMD32(pSrcCmplx)++; /* multiply complex number with real numbers */ #ifndef ARM_MATH_BIG_ENDIAN mul1 = (q31_t) ((q15_t) (inA1) * (q15_t) (inB1)); mul2 = (q31_t) ((q15_t) (inA1 >> 16) * (q15_t) (inB1)); mul3 = (q31_t) ((q15_t) (inA2) * (q15_t) (inB1 >> 16)); mul4 = (q31_t) ((q15_t) (inA2 >> 16) * (q15_t) (inB1 >> 16)); #else mul2 = (q31_t) ((q15_t) (inA1 >> 16) * (q15_t) (inB1 >> 16)); mul1 = (q31_t) ((q15_t) inA1 * (q15_t) (inB1 >> 16)); mul4 = (q31_t) ((q15_t) (inA2 >> 16) * (q15_t) inB1); mul3 = (q31_t) ((q15_t) inA2 * (q15_t) inB1); #endif // #ifndef ARM_MATH_BIG_ENDIAN /* saturate the result */ out1 = (q15_t) __SSAT(mul1 >> 15u, 16); out2 = (q15_t) __SSAT(mul2 >> 15u, 16); out3 = (q15_t) __SSAT(mul3 >> 15u, 16); out4 = (q15_t) __SSAT(mul4 >> 15u, 16); /* pack real and imaginary outputs and store them to destination */ *__SIMD32(pCmplxDst)++ = __PKHBT(out1, out2, 16); *__SIMD32(pCmplxDst)++ = __PKHBT(out3, out4, 16); inA1 = *__SIMD32(pSrcCmplx)++; inB1 = *__SIMD32(pSrcReal)++; inA2 = *__SIMD32(pSrcCmplx)++; #ifndef ARM_MATH_BIG_ENDIAN mul1 = (q31_t) ((q15_t) (inA1) * (q15_t) (inB1)); mul2 = (q31_t) ((q15_t) (inA1 >> 16) * (q15_t) (inB1)); mul3 = (q31_t) ((q15_t) (inA2) * (q15_t) (inB1 >> 16)); mul4 = (q31_t) ((q15_t) (inA2 >> 16) * (q15_t) (inB1 >> 16)); #else mul2 = (q31_t) ((q15_t) (inA1 >> 16) * (q15_t) (inB1 >> 16)); mul1 = (q31_t) ((q15_t) inA1 * (q15_t) (inB1 >> 16)); mul4 = (q31_t) ((q15_t) (inA2 >> 16) * (q15_t) inB1); mul3 = (q31_t) ((q15_t) inA2 * (q15_t) inB1); #endif // #ifndef ARM_MATH_BIG_ENDIAN out1 = (q15_t) __SSAT(mul1 >> 15u, 16); out2 = (q15_t) __SSAT(mul2 >> 15u, 16); out3 = (q15_t) __SSAT(mul3 >> 15u, 16); out4 = (q15_t) __SSAT(mul4 >> 15u, 16); *__SIMD32(pCmplxDst)++ = __PKHBT(out1, out2, 16); *__SIMD32(pCmplxDst)++ = __PKHBT(out3, out4, 16); /* Decrement the numSamples 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[2 * i] = A[2 * i] * B[i]. */ /* C[2 * i + 1] = A[2 * i + 1] * B[i]. */ in = *pSrcReal++; /* store the result in the destination buffer. */ *pCmplxDst++ = (q15_t) __SSAT((((q31_t) (*pSrcCmplx++) * (in)) >> 15), 16); *pCmplxDst++ = (q15_t) __SSAT((((q31_t) (*pSrcCmplx++) * (in)) >> 15), 16); /* Decrement the numSamples loop counter */ blkCnt--; } #else /* Run the below code for Cortex-M0 */ while(numSamples > 0u) { /* realOut = realA * realB. */ /* imagOut = imagA * realB. */ in = *pSrcReal++; /* store the result in the destination buffer. */ *pCmplxDst++ = (q15_t) __SSAT((((q31_t) (*pSrcCmplx++) * (in)) >> 15), 16); *pCmplxDst++ = (q15_t) __SSAT((((q31_t) (*pSrcCmplx++) * (in)) >> 15), 16); /* Decrement the numSamples loop counter */ numSamples--; } #endif /* #ifndef ARM_MATH_CM0_FAMILY */ } /** * @} end of CmplxByRealMult group */