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diff --git a/src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_decimate_fast_q31.c b/src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_decimate_fast_q31.c
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-/* ----------------------------------------------------------------------
-* Copyright (C) 2010 ARM Limited. All rights reserved.
-*
-* $Date: 15. February 2012
-* $Revision: V1.1.0
-*
-* Project: CMSIS DSP Library
-* Title: arm_fir_decimate_fast_q31.c
-*
-* Description: Fast Q31 FIR Decimator.
-*
-* Target Processor: Cortex-M4/Cortex-M3
-*
-* 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 groupFilters
- */
-
-/**
- * @addtogroup FIR_decimate
- * @{
- */
-
-/**
- * @brief Processing function for the Q31 FIR decimator (fast variant) for Cortex-M3 and Cortex-M4.
- * @param[in] *S points to an instance of the Q31 FIR decimator structure.
- * @param[in] *pSrc points to the block of input data.
- * @param[out] *pDst points to the block of output data
- * @param[in] blockSize number of input samples to process per call.
- * @return none
- *
- * <b>Scaling and Overflow Behavior:</b>
- *
- * \par
- * This function is optimized for speed at the expense of fixed-point precision and overflow protection.
- * The result of each 1.31 x 1.31 multiplication is truncated to 2.30 format.
- * These intermediate results are added to a 2.30 accumulator.
- * Finally, the accumulator is saturated and converted to a 1.31 result.
- * The fast version has the same overflow behavior as the standard version and provides less precision since it discards the low 32 bits of each multiplication result.
- * In order to avoid overflows completely the input signal must be scaled down by log2(numTaps) bits (where log2 is read as log to the base 2).
- *
- * \par
- * Refer to the function <code>arm_fir_decimate_q31()</code> for a slower implementation of this function which uses a 64-bit accumulator to provide higher precision.
- * Both the slow and the fast versions use the same instance structure.
- * Use the function <code>arm_fir_decimate_init_q31()</code> to initialize the filter structure.
- */
-
-void arm_fir_decimate_fast_q31(
- arm_fir_decimate_instance_q31 * S,
- q31_t * pSrc,
- q31_t * pDst,
- uint32_t blockSize)
-{
- q31_t *pState = S->pState; /* State pointer */
- q31_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
- q31_t *pStateCurnt; /* Points to the current sample of the state */
- q31_t x0, c0; /* Temporary variables to hold state and coefficient values */
- q31_t *px; /* Temporary pointers for state buffer */
- q31_t *pb; /* Temporary pointers for coefficient buffer */
- q31_t sum0; /* Accumulator */
- uint32_t numTaps = S->numTaps; /* Number of taps */
- uint32_t i, tapCnt, blkCnt, outBlockSize = blockSize / S->M; /* Loop counters */
- uint32_t blkCntN2;
- q31_t x1;
- q31_t acc0, acc1;
- q31_t *px0, *px1;
-
- /* S->pState buffer contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = S->pState + (numTaps - 1u);
-
- /* Total number of output samples to be computed */
-
- blkCnt = outBlockSize / 2;
- blkCntN2 = outBlockSize - (2 * blkCnt);
-
- while(blkCnt > 0u)
- {
- /* Copy decimation factor number of new input samples into the state buffer */
- i = 2 * S->M;
-
- do
- {
- *pStateCurnt++ = *pSrc++;
-
- } while(--i);
-
- /* Set accumulator to zero */
- acc0 = 0;
- acc1 = 0;
-
- /* Initialize state pointer */
- px0 = pState;
- px1 = pState + S->M;
-
- /* Initialize coeff pointer */
- pb = pCoeffs;
-
- /* Loop unrolling. Process 4 taps at a time. */
- tapCnt = numTaps >> 2;
-
- /* Loop over the number of taps. Unroll by a factor of 4.
- ** Repeat until we've computed numTaps-4 coefficients. */
- while(tapCnt > 0u)
- {
- /* Read the b[numTaps-1] coefficient */
- c0 = *(pb);
-
- /* Read x[n-numTaps-1] for sample 0 sample 1 */
- x0 = *(px0);
- x1 = *(px1);
-
- /* Perform the multiply-accumulate */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* Read the b[numTaps-2] coefficient */
- c0 = *(pb + 1u);
-
- /* Read x[n-numTaps-2] for sample 0 sample 1 */
- x0 = *(px0 + 1u);
- x1 = *(px1 + 1u);
-
- /* Perform the multiply-accumulate */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* Read the b[numTaps-3] coefficient */
- c0 = *(pb + 2u);
-
- /* Read x[n-numTaps-3] for sample 0 sample 1 */
- x0 = *(px0 + 2u);
- x1 = *(px1 + 2u);
- pb += 4u;
-
- /* Perform the multiply-accumulate */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* Read the b[numTaps-4] coefficient */
- c0 = *(pb - 1u);
-
- /* Read x[n-numTaps-4] for sample 0 sample 1 */
- x0 = *(px0 + 3u);
- x1 = *(px1 + 3u);
-
-
- /* Perform the multiply-accumulate */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* update state pointers */
- px0 += 4u;
- px1 += 4u;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps */
- tapCnt = numTaps % 0x4u;
-
- while(tapCnt > 0u)
- {
- /* Read coefficients */
- c0 = *(pb++);
-
- /* Fetch 1 state variable */
- x0 = *(px0++);
- x1 = *(px1++);
-
- /* Perform the multiply-accumulate */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Advance the state pointer by the decimation factor
- * to process the next group of decimation factor number samples */
- pState = pState + S->M * 2;
-
- /* The result is in the accumulator, store in the destination buffer. */
- *pDst++ = (q31_t) (acc0 << 1);
- *pDst++ = (q31_t) (acc1 << 1);
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- while(blkCntN2 > 0u)
- {
- /* Copy decimation factor number of new input samples into the state buffer */
- i = S->M;
-
- do
- {
- *pStateCurnt++ = *pSrc++;
-
- } while(--i);
-
- /* Set accumulator to zero */
- sum0 = 0;
-
- /* Initialize state pointer */
- px = pState;
-
- /* Initialize coeff pointer */
- pb = pCoeffs;
-
- /* Loop unrolling. Process 4 taps at a time. */
- tapCnt = numTaps >> 2;
-
- /* Loop over the number of taps. Unroll by a factor of 4.
- ** Repeat until we've computed numTaps-4 coefficients. */
- while(tapCnt > 0u)
- {
- /* Read the b[numTaps-1] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-1] sample */
- x0 = *(px++);
-
- /* Perform the multiply-accumulate */
- sum0 = (q31_t) ((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Read the b[numTaps-2] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-2] sample */
- x0 = *(px++);
-
- /* Perform the multiply-accumulate */
- sum0 = (q31_t) ((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Read the b[numTaps-3] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-3] sample */
- x0 = *(px++);
-
- /* Perform the multiply-accumulate */
- sum0 = (q31_t) ((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Read the b[numTaps-4] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-4] sample */
- x0 = *(px++);
-
- /* Perform the multiply-accumulate */
- sum0 = (q31_t) ((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps */
- tapCnt = numTaps % 0x4u;
-
- while(tapCnt > 0u)
- {
- /* Read coefficients */
- c0 = *(pb++);
-
- /* Fetch 1 state variable */
- x0 = *(px++);
-
- /* Perform the multiply-accumulate */
- sum0 = (q31_t) ((((q63_t) sum0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Advance the state pointer by the decimation factor
- * to process the next group of decimation factor number samples */
- pState = pState + S->M;
-
- /* The result is in the accumulator, store in the destination buffer. */
- *pDst++ = (q31_t) (sum0 << 1);
-
- /* Decrement the loop counter */
- blkCntN2--;
- }
-
- /* Processing is complete.
- ** Now copy the last numTaps - 1 samples to the satrt of the state buffer.
- ** This prepares the state buffer for the next function call. */
-
- /* Points to the start of the state buffer */
- pStateCurnt = S->pState;
-
- i = (numTaps - 1u) >> 2u;
-
- /* copy data */
- while(i > 0u)
- {
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- i--;
- }
-
- i = (numTaps - 1u) % 0x04u;
-
- /* copy data */
- while(i > 0u)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- i--;
- }
-}
-
-/**
- * @} end of FIR_decimate group
- */
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