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Diffstat (limited to 'src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_fast_q31.c')
| -rw-r--r-- | src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_fast_q31.c | 309 |
1 files changed, 0 insertions, 309 deletions
diff --git a/src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_fast_q31.c b/src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_fast_q31.c deleted file mode 100644 index e384ff973..000000000 --- a/src/modules/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_fir_fast_q31.c +++ /dev/null @@ -1,309 +0,0 @@ -/* ----------------------------------------------------------------------
-* Copyright (C) 2010 ARM Limited. All rights reserved.
-*
-* $Date: 15. February 2012
-* $Revision: V1.1.0
-*
-* Project: CMSIS DSP Library
-* Title: arm_fir_fast_q31.c
-*
-* Description: Processing function for the Q31 Fast FIR filter.
-*
-* 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.
-*
-* Version 0.0.9 2010/08/27
-* Initial version
-* -------------------------------------------------------------------- */
-
-#include "arm_math.h"
-
-/**
- * @ingroup groupFilters
- */
-
-/**
- * @addtogroup FIR
- * @{
- */
-
-/**
- * @param[in] *S points to an instance of the Q31 structure.
- * @param[in] *pSrc points to the block of input data.
- * @param[out] *pDst points to the block output data.
- * @param[in] blockSize number of 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.
- *
- * \par
- * Refer to the function <code>arm_fir_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_init_q31()</code> to initialize the filter structure.
- */
-
-void arm_fir_fast_q31(
- const arm_fir_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, x1, x2, x3; /* Temporary variables to hold state */
- q31_t c0; /* Temporary variable to hold coefficient value */
- q31_t *px; /* Temporary pointer for state */
- q31_t *pb; /* Temporary pointer for coefficient buffer */
- q31_t acc0, acc1, acc2, acc3; /* Accumulators */
- uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
- uint32_t i, tapCnt, blkCnt; /* Loop counters */
-
- /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = &(S->pState[(numTaps - 1u)]);
-
- /* Apply loop unrolling and compute 4 output values simultaneously.
- * The variables acc0 ... acc3 hold output values that are being computed:
- *
- * acc0 = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0]
- * acc1 = b[numTaps-1] * x[n-numTaps] + b[numTaps-2] * x[n-numTaps-1] + b[numTaps-3] * x[n-numTaps-2] +...+ b[0] * x[1]
- * acc2 = b[numTaps-1] * x[n-numTaps+1] + b[numTaps-2] * x[n-numTaps] + b[numTaps-3] * x[n-numTaps-1] +...+ b[0] * x[2]
- * acc3 = b[numTaps-1] * x[n-numTaps+2] + b[numTaps-2] * x[n-numTaps+1] + b[numTaps-3] * x[n-numTaps] +...+ b[0] * x[3]
- */
- blkCnt = blockSize >> 2;
-
- /* 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)
- {
- /* Copy four new input samples into the state buffer */
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
-
- /* Set all accumulators to zero */
- acc0 = 0;
- acc1 = 0;
- acc2 = 0;
- acc3 = 0;
-
- /* Initialize state pointer */
- px = pState;
-
- /* Initialize coefficient pointer */
- pb = pCoeffs;
-
- /* Read the first three samples from the state buffer:
- * x[n-numTaps], x[n-numTaps-1], x[n-numTaps-2] */
- x0 = *(px++);
- x1 = *(px++);
- x2 = *(px++);
-
- /* Loop unrolling. Process 4 taps at a time. */
- tapCnt = numTaps >> 2;
- i = tapCnt;
-
- while(i > 0u)
- {
- /* Read the b[numTaps] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-3] sample */
- x3 = *(px++);
-
- /* acc0 += b[numTaps] * x[n-numTaps] */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* acc1 += b[numTaps] * x[n-numTaps-1] */
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* acc2 += b[numTaps] * x[n-numTaps-2] */
- acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x2 * c0)) >> 32);
-
- /* acc3 += b[numTaps] * x[n-numTaps-3] */
- acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x3 * c0)) >> 32);
-
- /* Read the b[numTaps-1] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-4] sample */
- x0 = *(px++);
-
- /* Perform the multiply-accumulates */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x1 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x2 * c0)) >> 32);
- acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x3 * c0)) >> 32);
- acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x0 * c0)) >> 32);
-
- /* Read the b[numTaps-2] coefficient */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-5] sample */
- x1 = *(px++);
-
- /* Perform the multiply-accumulates */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x2 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x3 * c0)) >> 32);
- acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x1 * c0)) >> 32);
-
- /* Read the b[numTaps-3] coefficients */
- c0 = *(pb++);
-
- /* Read x[n-numTaps-6] sample */
- x2 = *(px++);
-
- /* Perform the multiply-accumulates */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x3 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x1 * c0)) >> 32);
- acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x2 * c0)) >> 32);
- i--;
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps */
-
- i = numTaps - (tapCnt * 4u);
- while(i > 0u)
- {
- /* Read coefficients */
- c0 = *(pb++);
-
- /* Fetch 1 state variable */
- x3 = *(px++);
-
- /* Perform the multiply-accumulates */
- acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
- acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
- acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x2 * c0)) >> 32);
- acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x3 * c0)) >> 32);
-
- /* Reuse the present sample states for next sample */
- x0 = x1;
- x1 = x2;
- x2 = x3;
-
- /* Decrement the loop counter */
- i--;
- }
-
- /* Advance the state pointer by 4 to process the next group of 4 samples */
- pState = pState + 4;
-
- /* The results in the 4 accumulators are in 2.30 format. Convert to 1.31
- ** Then store the 4 outputs in the destination buffer. */
- *pDst++ = (q31_t) (acc0 << 1);
- *pDst++ = (q31_t) (acc1 << 1);
- *pDst++ = (q31_t) (acc2 << 1);
- *pDst++ = (q31_t) (acc3 << 1);
-
- /* Decrement the samples 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 % 4u;
-
- while(blkCnt > 0u)
- {
- /* Copy one sample at a time into state buffer */
- *pStateCurnt++ = *pSrc++;
-
- /* Set the accumulator to zero */
- acc0 = 0;
-
- /* Initialize state pointer */
- px = pState;
-
- /* Initialize Coefficient pointer */
- pb = (pCoeffs);
-
- i = numTaps;
-
- /* Perform the multiply-accumulates */
- do
- {
- acc0 =
- (q31_t) ((((q63_t) acc0 << 32) +
- ((q63_t) (*px++) * (*(pb++)))) >> 32);
- i--;
- } while(i > 0u);
-
- /* The result is in 2.30 format. Convert to 1.31
- ** Then store the output in the destination buffer. */
- *pDst++ = (q31_t) (acc0 << 1);
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1;
-
- /* Decrement the samples loop counter */
- blkCnt--;
- }
-
- /* 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;
-
- tapCnt = (numTaps - 1u) >> 2u;
-
- /* copy data */
- while(tapCnt > 0u)
- {
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
- /* Calculate remaining number of copies */
- tapCnt = (numTaps - 1u) % 0x4u;
-
- /* Copy the remaining q31_t data */
- while(tapCnt > 0u)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
-
-}
-
-/**
- * @} end of FIR group
- */
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