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Diffstat (limited to 'fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_f32.c')
| -rw-r--r-- | fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_f32.c | 985 |
1 files changed, 985 insertions, 0 deletions
diff --git a/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_f32.c b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_f32.c new file mode 100644 index 0000000..812f9df --- /dev/null +++ b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_f32.c @@ -0,0 +1,985 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_fir_f32.c
+ * Description: Floating-point FIR filter processing function
+ *
+ * $Date: 27. January 2017
+ * $Revision: V.1.5.1
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "arm_math.h"
+
+/**
+* @ingroup groupFilters
+*/
+
+/**
+* @defgroup FIR Finite Impulse Response (FIR) Filters
+*
+* This set of functions implements Finite Impulse Response (FIR) filters
+* for Q7, Q15, Q31, and floating-point data types. Fast versions of Q15 and Q31 are also provided.
+* The functions operate on blocks of input and output data and each call to the function processes
+* <code>blockSize</code> samples through the filter. <code>pSrc</code> and
+* <code>pDst</code> points to input and output arrays containing <code>blockSize</code> values.
+*
+* \par Algorithm:
+* The FIR filter algorithm is based upon a sequence of multiply-accumulate (MAC) operations.
+* Each filter coefficient <code>b[n]</code> is multiplied by a state variable which equals a previous input sample <code>x[n]</code>.
+* <pre>
+* y[n] = b[0] * x[n] + b[1] * x[n-1] + b[2] * x[n-2] + ...+ b[numTaps-1] * x[n-numTaps+1]
+* </pre>
+* \par
+* \image html FIR.gif "Finite Impulse Response filter"
+* \par
+* <code>pCoeffs</code> points to a coefficient array of size <code>numTaps</code>.
+* Coefficients are stored in time reversed order.
+* \par
+* <pre>
+* {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}
+* </pre>
+* \par
+* <code>pState</code> points to a state array of size <code>numTaps + blockSize - 1</code>.
+* Samples in the state buffer are stored in the following order.
+* \par
+* <pre>
+* {x[n-numTaps+1], x[n-numTaps], x[n-numTaps-1], x[n-numTaps-2]....x[0], x[1], ..., x[blockSize-1]}
+* </pre>
+* \par
+* Note that the length of the state buffer exceeds the length of the coefficient array by <code>blockSize-1</code>.
+* The increased state buffer length allows circular addressing, which is traditionally used in the FIR filters,
+* to be avoided and yields a significant speed improvement.
+* The state variables are updated after each block of data is processed; the coefficients are untouched.
+* \par Instance Structure
+* The coefficients and state variables for a filter are stored together in an instance data structure.
+* A separate instance structure must be defined for each filter.
+* Coefficient arrays may be shared among several instances while state variable arrays cannot be shared.
+* There are separate instance structure declarations for each of the 4 supported data types.
+*
+* \par Initialization Functions
+* There is also an associated initialization function for each data type.
+* The initialization function performs the following operations:
+* - Sets the values of the internal structure fields.
+* - Zeros out the values in the state buffer.
+* To do this manually without calling the init function, assign the follow subfields of the instance structure:
+* numTaps, pCoeffs, pState. Also set all of the values in pState to zero.
+*
+* \par
+* Use of the initialization function is optional.
+* However, if the initialization function is used, then the instance structure cannot be placed into a const data section.
+* To place an instance structure into a const data section, the instance structure must be manually initialized.
+* Set the values in the state buffer to zeros before static initialization.
+* The code below statically initializes each of the 4 different data type filter instance structures
+* <pre>
+*arm_fir_instance_f32 S = {numTaps, pState, pCoeffs};
+*arm_fir_instance_q31 S = {numTaps, pState, pCoeffs};
+*arm_fir_instance_q15 S = {numTaps, pState, pCoeffs};
+*arm_fir_instance_q7 S = {numTaps, pState, pCoeffs};
+* </pre>
+*
+* where <code>numTaps</code> is the number of filter coefficients in the filter; <code>pState</code> is the address of the state buffer;
+* <code>pCoeffs</code> is the address of the coefficient buffer.
+*
+* \par Fixed-Point Behavior
+* Care must be taken when using the fixed-point versions of the FIR filter functions.
+* In particular, the overflow and saturation behavior of the accumulator used in each function must be considered.
+* Refer to the function specific documentation below for usage guidelines.
+*/
+
+/**
+* @addtogroup FIR
+* @{
+*/
+
+/**
+*
+* @param[in] *S points to an instance of the floating-point FIR filter 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 samples to process per call.
+* @return none.
+*
+*/
+
+#if defined(ARM_MATH_CM7)
+
+void arm_fir_f32(
+const arm_fir_instance_f32 * S,
+float32_t * pSrc,
+float32_t * pDst,
+uint32_t blockSize)
+{
+ float32_t *pState = S->pState; /* State pointer */
+ float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
+ float32_t *pStateCurnt; /* Points to the current sample of the state */
+ float32_t *px, *pb; /* Temporary pointers for state and coefficient buffers */
+ float32_t acc0, acc1, acc2, acc3, acc4, acc5, acc6, acc7; /* Accumulators */
+ float32_t x0, x1, x2, x3, x4, x5, x6, x7, c0; /* Temporary variables to hold state and coefficient values */
+ uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
+ uint32_t i, tapCnt, blkCnt; /* Loop counters */
+
+ /* S->pState points to state array 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 8 output values simultaneously.
+ * The variables acc0 ... acc7 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 >> 3;
+
+ /* First part of the processing with loop unrolling. Compute 8 outputs at a time.
+ ** a second loop below computes the remaining 1 to 7 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 = 0.0f;
+ acc1 = 0.0f;
+ acc2 = 0.0f;
+ acc3 = 0.0f;
+ acc4 = 0.0f;
+ acc5 = 0.0f;
+ acc6 = 0.0f;
+ acc7 = 0.0f;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize coeff pointer */
+ pb = (pCoeffs);
+
+ /* This is separated from the others to avoid
+ * a call to __aeabi_memmove which would be slower
+ */
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+
+ /* Read the first seven samples from the state buffer: x[n-numTaps], x[n-numTaps-1], x[n-numTaps-2] */
+ x0 = *px++;
+ x1 = *px++;
+ x2 = *px++;
+ x3 = *px++;
+ x4 = *px++;
+ x5 = *px++;
+ x6 = *px++;
+
+ /* Loop unrolling. Process 8 taps at a time. */
+ tapCnt = numTaps >> 3U;
+
+ /* Loop over the number of taps. Unroll by a factor of 8.
+ ** Repeat until we've computed numTaps-8 coefficients. */
+ while (tapCnt > 0U)
+ {
+ /* Read the b[numTaps-1] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-3] sample */
+ x7 = *(px++);
+
+ /* acc0 += b[numTaps-1] * x[n-numTaps] */
+ acc0 += x0 * c0;
+
+ /* acc1 += b[numTaps-1] * x[n-numTaps-1] */
+ acc1 += x1 * c0;
+
+ /* acc2 += b[numTaps-1] * x[n-numTaps-2] */
+ acc2 += x2 * c0;
+
+ /* acc3 += b[numTaps-1] * x[n-numTaps-3] */
+ acc3 += x3 * c0;
+
+ /* acc4 += b[numTaps-1] * x[n-numTaps-4] */
+ acc4 += x4 * c0;
+
+ /* acc1 += b[numTaps-1] * x[n-numTaps-5] */
+ acc5 += x5 * c0;
+
+ /* acc2 += b[numTaps-1] * x[n-numTaps-6] */
+ acc6 += x6 * c0;
+
+ /* acc3 += b[numTaps-1] * x[n-numTaps-7] */
+ acc7 += x7 * c0;
+
+ /* Read the b[numTaps-2] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-4] sample */
+ x0 = *(px++);
+
+ /* Perform the multiply-accumulate */
+ acc0 += x1 * c0;
+ acc1 += x2 * c0;
+ acc2 += x3 * c0;
+ acc3 += x4 * c0;
+ acc4 += x5 * c0;
+ acc5 += x6 * c0;
+ acc6 += x7 * c0;
+ acc7 += x0 * c0;
+
+ /* Read the b[numTaps-3] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-5] sample */
+ x1 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x2 * c0;
+ acc1 += x3 * c0;
+ acc2 += x4 * c0;
+ acc3 += x5 * c0;
+ acc4 += x6 * c0;
+ acc5 += x7 * c0;
+ acc6 += x0 * c0;
+ acc7 += x1 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x2 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x3 * c0;
+ acc1 += x4 * c0;
+ acc2 += x5 * c0;
+ acc3 += x6 * c0;
+ acc4 += x7 * c0;
+ acc5 += x0 * c0;
+ acc6 += x1 * c0;
+ acc7 += x2 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x3 = *(px++);
+ /* Perform the multiply-accumulates */
+ acc0 += x4 * c0;
+ acc1 += x5 * c0;
+ acc2 += x6 * c0;
+ acc3 += x7 * c0;
+ acc4 += x0 * c0;
+ acc5 += x1 * c0;
+ acc6 += x2 * c0;
+ acc7 += x3 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x4 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x5 * c0;
+ acc1 += x6 * c0;
+ acc2 += x7 * c0;
+ acc3 += x0 * c0;
+ acc4 += x1 * c0;
+ acc5 += x2 * c0;
+ acc6 += x3 * c0;
+ acc7 += x4 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x5 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x6 * c0;
+ acc1 += x7 * c0;
+ acc2 += x0 * c0;
+ acc3 += x1 * c0;
+ acc4 += x2 * c0;
+ acc5 += x3 * c0;
+ acc6 += x4 * c0;
+ acc7 += x5 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x6 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x7 * c0;
+ acc1 += x0 * c0;
+ acc2 += x1 * c0;
+ acc3 += x2 * c0;
+ acc4 += x3 * c0;
+ acc5 += x4 * c0;
+ acc6 += x5 * c0;
+ acc7 += x6 * c0;
+
+ tapCnt--;
+ }
+
+ /* If the filter length is not a multiple of 8, compute the remaining filter taps */
+ tapCnt = numTaps % 0x8U;
+
+ while (tapCnt > 0U)
+ {
+ /* Read coefficients */
+ c0 = *(pb++);
+
+ /* Fetch 1 state variable */
+ x7 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ acc0 += x0 * c0;
+ acc1 += x1 * c0;
+ acc2 += x2 * c0;
+ acc3 += x3 * c0;
+ acc4 += x4 * c0;
+ acc5 += x5 * c0;
+ acc6 += x6 * c0;
+ acc7 += x7 * c0;
+
+ /* Reuse the present sample states for next sample */
+ x0 = x1;
+ x1 = x2;
+ x2 = x3;
+ x3 = x4;
+ x4 = x5;
+ x5 = x6;
+ x6 = x7;
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+ /* Advance the state pointer by 8 to process the next group of 8 samples */
+ pState = pState + 8;
+
+ /* The results in the 8 accumulators, store in the destination buffer. */
+ *pDst++ = acc0;
+ *pDst++ = acc1;
+ *pDst++ = acc2;
+ *pDst++ = acc3;
+ *pDst++ = acc4;
+ *pDst++ = acc5;
+ *pDst++ = acc6;
+ *pDst++ = acc7;
+
+ blkCnt--;
+ }
+
+ /* If the blockSize is not a multiple of 8, compute any remaining output samples here.
+ ** No loop unrolling is used. */
+ blkCnt = blockSize % 0x8U;
+
+ while (blkCnt > 0U)
+ {
+ /* Copy one sample at a time into state buffer */
+ *pStateCurnt++ = *pSrc++;
+
+ /* Set the accumulator to zero */
+ acc0 = 0.0f;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize Coefficient pointer */
+ pb = (pCoeffs);
+
+ i = numTaps;
+
+ /* Perform the multiply-accumulates */
+ do
+ {
+ acc0 += *px++ * *pb++;
+ i--;
+
+ } while (i > 0U);
+
+ /* The result is store in the destination buffer. */
+ *pDst++ = acc0;
+
+ /* Advance state pointer by 1 for the next sample */
+ pState = pState + 1;
+
+ blkCnt--;
+ }
+
+ /* Processing is complete.
+ ** Now copy the last numTaps - 1 samples to the start 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--;
+ }
+}
+
+#elif defined(ARM_MATH_CM0_FAMILY)
+
+void arm_fir_f32(
+const arm_fir_instance_f32 * S,
+float32_t * pSrc,
+float32_t * pDst,
+uint32_t blockSize)
+{
+ float32_t *pState = S->pState; /* State pointer */
+ float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
+ float32_t *pStateCurnt; /* Points to the current sample of the state */
+ float32_t *px, *pb; /* Temporary pointers for state and coefficient buffers */
+ uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
+ uint32_t i, tapCnt, blkCnt; /* Loop counters */
+
+ /* Run the below code for Cortex-M0 */
+
+ float32_t acc;
+
+ /* S->pState points to state array 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)]);
+
+ /* Initialize blkCnt with blockSize */
+ blkCnt = blockSize;
+
+ while (blkCnt > 0U)
+ {
+ /* Copy one sample at a time into state buffer */
+ *pStateCurnt++ = *pSrc++;
+
+ /* Set the accumulator to zero */
+ acc = 0.0f;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize Coefficient pointer */
+ pb = pCoeffs;
+
+ i = numTaps;
+
+ /* Perform the multiply-accumulates */
+ do
+ {
+ /* acc = 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] */
+ acc += *px++ * *pb++;
+ i--;
+
+ } while (i > 0U);
+
+ /* The result is store in the destination buffer. */
+ *pDst++ = acc;
+
+ /* Advance state pointer by 1 for the next sample */
+ pState = pState + 1;
+
+ blkCnt--;
+ }
+
+ /* Processing is complete.
+ ** Now copy the last numTaps - 1 samples to the starting 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;
+
+ /* Copy numTaps number of values */
+ tapCnt = numTaps - 1U;
+
+ /* Copy data */
+ while (tapCnt > 0U)
+ {
+ *pStateCurnt++ = *pState++;
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+}
+
+#else
+
+/* Run the below code for Cortex-M4 and Cortex-M3 */
+
+void arm_fir_f32(
+const arm_fir_instance_f32 * S,
+float32_t * pSrc,
+float32_t * pDst,
+uint32_t blockSize)
+{
+ float32_t *pState = S->pState; /* State pointer */
+ float32_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
+ float32_t *pStateCurnt; /* Points to the current sample of the state */
+ float32_t *px, *pb; /* Temporary pointers for state and coefficient buffers */
+ float32_t acc0, acc1, acc2, acc3, acc4, acc5, acc6, acc7; /* Accumulators */
+ float32_t x0, x1, x2, x3, x4, x5, x6, x7, c0; /* Temporary variables to hold state and coefficient values */
+ uint32_t numTaps = S->numTaps; /* Number of filter coefficients in the filter */
+ uint32_t i, tapCnt, blkCnt; /* Loop counters */
+ float32_t p0,p1,p2,p3,p4,p5,p6,p7; /* Temporary product values */
+
+ /* S->pState points to state array 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 8 output values simultaneously.
+ * The variables acc0 ... acc7 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 >> 3;
+
+ /* First part of the processing with loop unrolling. Compute 8 outputs at a time.
+ ** a second loop below computes the remaining 1 to 7 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 = 0.0f;
+ acc1 = 0.0f;
+ acc2 = 0.0f;
+ acc3 = 0.0f;
+ acc4 = 0.0f;
+ acc5 = 0.0f;
+ acc6 = 0.0f;
+ acc7 = 0.0f;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize coeff pointer */
+ pb = (pCoeffs);
+
+ /* This is separated from the others to avoid
+ * a call to __aeabi_memmove which would be slower
+ */
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+ *pStateCurnt++ = *pSrc++;
+
+ /* Read the first seven samples from the state buffer: x[n-numTaps], x[n-numTaps-1], x[n-numTaps-2] */
+ x0 = *px++;
+ x1 = *px++;
+ x2 = *px++;
+ x3 = *px++;
+ x4 = *px++;
+ x5 = *px++;
+ x6 = *px++;
+
+ /* Loop unrolling. Process 8 taps at a time. */
+ tapCnt = numTaps >> 3U;
+
+ /* Loop over the number of taps. Unroll by a factor of 8.
+ ** Repeat until we've computed numTaps-8 coefficients. */
+ while (tapCnt > 0U)
+ {
+ /* Read the b[numTaps-1] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-3] sample */
+ x7 = *(px++);
+
+ /* acc0 += b[numTaps-1] * x[n-numTaps] */
+ p0 = x0 * c0;
+
+ /* acc1 += b[numTaps-1] * x[n-numTaps-1] */
+ p1 = x1 * c0;
+
+ /* acc2 += b[numTaps-1] * x[n-numTaps-2] */
+ p2 = x2 * c0;
+
+ /* acc3 += b[numTaps-1] * x[n-numTaps-3] */
+ p3 = x3 * c0;
+
+ /* acc4 += b[numTaps-1] * x[n-numTaps-4] */
+ p4 = x4 * c0;
+
+ /* acc1 += b[numTaps-1] * x[n-numTaps-5] */
+ p5 = x5 * c0;
+
+ /* acc2 += b[numTaps-1] * x[n-numTaps-6] */
+ p6 = x6 * c0;
+
+ /* acc3 += b[numTaps-1] * x[n-numTaps-7] */
+ p7 = x7 * c0;
+
+ /* Read the b[numTaps-2] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-4] sample */
+ x0 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+
+ /* Perform the multiply-accumulate */
+ p0 = x1 * c0;
+ p1 = x2 * c0;
+ p2 = x3 * c0;
+ p3 = x4 * c0;
+ p4 = x5 * c0;
+ p5 = x6 * c0;
+ p6 = x7 * c0;
+ p7 = x0 * c0;
+
+ /* Read the b[numTaps-3] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-5] sample */
+ x1 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x2 * c0;
+ p1 = x3 * c0;
+ p2 = x4 * c0;
+ p3 = x5 * c0;
+ p4 = x6 * c0;
+ p5 = x7 * c0;
+ p6 = x0 * c0;
+ p7 = x1 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x2 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x3 * c0;
+ p1 = x4 * c0;
+ p2 = x5 * c0;
+ p3 = x6 * c0;
+ p4 = x7 * c0;
+ p5 = x0 * c0;
+ p6 = x1 * c0;
+ p7 = x2 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x3 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x4 * c0;
+ p1 = x5 * c0;
+ p2 = x6 * c0;
+ p3 = x7 * c0;
+ p4 = x0 * c0;
+ p5 = x1 * c0;
+ p6 = x2 * c0;
+ p7 = x3 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x4 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x5 * c0;
+ p1 = x6 * c0;
+ p2 = x7 * c0;
+ p3 = x0 * c0;
+ p4 = x1 * c0;
+ p5 = x2 * c0;
+ p6 = x3 * c0;
+ p7 = x4 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x5 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x6 * c0;
+ p1 = x7 * c0;
+ p2 = x0 * c0;
+ p3 = x1 * c0;
+ p4 = x2 * c0;
+ p5 = x3 * c0;
+ p6 = x4 * c0;
+ p7 = x5 * c0;
+
+ /* Read the b[numTaps-4] coefficient */
+ c0 = *(pb++);
+
+ /* Read x[n-numTaps-6] sample */
+ x6 = *(px++);
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Perform the multiply-accumulates */
+ p0 = x7 * c0;
+ p1 = x0 * c0;
+ p2 = x1 * c0;
+ p3 = x2 * c0;
+ p4 = x3 * c0;
+ p5 = x4 * c0;
+ p6 = x5 * c0;
+ p7 = x6 * c0;
+
+ tapCnt--;
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+ }
+
+ /* If the filter length is not a multiple of 8, compute the remaining filter taps */
+ tapCnt = numTaps % 0x8U;
+
+ while (tapCnt > 0U)
+ {
+ /* Read coefficients */
+ c0 = *(pb++);
+
+ /* Fetch 1 state variable */
+ x7 = *(px++);
+
+ /* Perform the multiply-accumulates */
+ p0 = x0 * c0;
+ p1 = x1 * c0;
+ p2 = x2 * c0;
+ p3 = x3 * c0;
+ p4 = x4 * c0;
+ p5 = x5 * c0;
+ p6 = x6 * c0;
+ p7 = x7 * c0;
+
+ /* Reuse the present sample states for next sample */
+ x0 = x1;
+ x1 = x2;
+ x2 = x3;
+ x3 = x4;
+ x4 = x5;
+ x5 = x6;
+ x6 = x7;
+
+ acc0 += p0;
+ acc1 += p1;
+ acc2 += p2;
+ acc3 += p3;
+ acc4 += p4;
+ acc5 += p5;
+ acc6 += p6;
+ acc7 += p7;
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+ /* Advance the state pointer by 8 to process the next group of 8 samples */
+ pState = pState + 8;
+
+ /* The results in the 8 accumulators, store in the destination buffer. */
+ *pDst++ = acc0;
+ *pDst++ = acc1;
+ *pDst++ = acc2;
+ *pDst++ = acc3;
+ *pDst++ = acc4;
+ *pDst++ = acc5;
+ *pDst++ = acc6;
+ *pDst++ = acc7;
+
+ blkCnt--;
+ }
+
+ /* If the blockSize is not a multiple of 8, compute any remaining output samples here.
+ ** No loop unrolling is used. */
+ blkCnt = blockSize % 0x8U;
+
+ while (blkCnt > 0U)
+ {
+ /* Copy one sample at a time into state buffer */
+ *pStateCurnt++ = *pSrc++;
+
+ /* Set the accumulator to zero */
+ acc0 = 0.0f;
+
+ /* Initialize state pointer */
+ px = pState;
+
+ /* Initialize Coefficient pointer */
+ pb = (pCoeffs);
+
+ i = numTaps;
+
+ /* Perform the multiply-accumulates */
+ do
+ {
+ acc0 += *px++ * *pb++;
+ i--;
+
+ } while (i > 0U);
+
+ /* The result is store in the destination buffer. */
+ *pDst++ = acc0;
+
+ /* Advance state pointer by 1 for the next sample */
+ pState = pState + 1;
+
+ blkCnt--;
+ }
+
+ /* Processing is complete.
+ ** Now copy the last numTaps - 1 samples to the start 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--;
+ }
+}
+
+#endif
+
+/**
+* @} end of FIR group
+*/
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