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author | px4dev <px4@purgatory.org> | 2013-01-06 12:52:05 -0800 |
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committer | px4dev <px4@purgatory.org> | 2013-01-06 12:52:05 -0800 |
commit | 4447282260be0780eb6e36f5e953bf56888a5688 (patch) | |
tree | 3ba1e976d998d433397343b79a0612af52075aef /apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c | |
parent | 659543f852d18197f68fafee5db5671567b74f4b (diff) | |
download | px4-firmware-4447282260be0780eb6e36f5e953bf56888a5688.tar.gz px4-firmware-4447282260be0780eb6e36f5e953bf56888a5688.tar.bz2 px4-firmware-4447282260be0780eb6e36f5e953bf56888a5688.zip |
Integrate the interesting parts of the CMSIS 3.01 (r3p1) DSP library
Diffstat (limited to 'apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c')
-rw-r--r-- | apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c b/apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c new file mode 100644 index 000000000..6749b01b3 --- /dev/null +++ b/apps/mathlib/CMSIS/DSP_Lib/Source/FilteringFunctions/arm_correlate_opt_q7.c @@ -0,0 +1,463 @@ +/* ----------------------------------------------------------------------
+* Copyright (C) 2010 ARM Limited. All rights reserved.
+*
+* $Date: 15. February 2012
+* $Revision: V1.1.0
+*
+* Project: CMSIS DSP Library
+* Title: arm_correlate_opt_q7.c
+*
+* Description: Correlation of Q7 sequences.
+*
+* Target Processor: Cortex-M4/Cortex-M3
+*
+* Version 1.1.0 2012/02/15
+* Updated with more optimizations, bug fixes and minor API changes.
+*
+* Version 1.0.11 2011/10/18
+* Bug Fix in conv, correlation, partial convolution.
+*
+* 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 0.0.7 2010/06/10
+* Misra-C changes done
+*
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupFilters
+ */
+
+/**
+ * @addtogroup Corr
+ * @{
+ */
+
+/**
+ * @brief Correlation of Q7 sequences.
+ * @param[in] *pSrcA points to the first input sequence.
+ * @param[in] srcALen length of the first input sequence.
+ * @param[in] *pSrcB points to the second input sequence.
+ * @param[in] srcBLen length of the second input sequence.
+ * @param[out] *pDst points to the location where the output result is written. Length 2 * max(srcALen, srcBLen) - 1.
+ * @param[in] *pScratch1 points to scratch buffer(of type q15_t) of size max(srcALen, srcBLen) + 2*min(srcALen, srcBLen) - 2.
+ * @param[in] *pScratch2 points to scratch buffer (of type q15_t) of size min(srcALen, srcBLen).
+ * @return none.
+ *
+ *
+ * \par Restrictions
+ * If the silicon does not support unaligned memory access enable the macro UNALIGNED_SUPPORT_DISABLE
+ * In this case input, output, scratch1 and scratch2 buffers should be aligned by 32-bit
+ *
+ * @details
+ * <b>Scaling and Overflow Behavior:</b>
+ *
+ * \par
+ * The function is implemented using a 32-bit internal accumulator.
+ * Both the inputs are represented in 1.7 format and multiplications yield a 2.14 result.
+ * The 2.14 intermediate results are accumulated in a 32-bit accumulator in 18.14 format.
+ * This approach provides 17 guard bits and there is no risk of overflow as long as <code>max(srcALen, srcBLen)<131072</code>.
+ * The 18.14 result is then truncated to 18.7 format by discarding the low 7 bits and saturated to 1.7 format.
+ *
+ *
+ */
+
+
+
+void arm_correlate_opt_q7(
+ q7_t * pSrcA,
+ uint32_t srcALen,
+ q7_t * pSrcB,
+ uint32_t srcBLen,
+ q7_t * pDst,
+ q15_t * pScratch1,
+ q15_t * pScratch2)
+{
+ q7_t *pOut = pDst; /* output pointer */
+ q15_t *pScr1 = pScratch1; /* Temporary pointer for scratch */
+ q15_t *pScr2 = pScratch2; /* Temporary pointer for scratch */
+ q7_t *pIn1; /* inputA pointer */
+ q7_t *pIn2; /* inputB pointer */
+ q15_t *py; /* Intermediate inputB pointer */
+ q31_t acc0, acc1, acc2, acc3; /* Accumulators */
+ uint32_t j, k = 0u, blkCnt; /* loop counter */
+ int32_t inc = 1; /* output pointer increment */
+ uint32_t outBlockSize; /* loop counter */
+ q15_t x4; /* Temporary input variable */
+ uint32_t tapCnt; /* loop counter */
+ q31_t x1, x2, x3, y1; /* Temporary input variables */
+
+ /* The algorithm implementation is based on the lengths of the inputs. */
+ /* srcB is always made to slide across srcA. */
+ /* So srcBLen is always considered as shorter or equal to srcALen */
+ /* But CORR(x, y) is reverse of CORR(y, x) */
+ /* So, when srcBLen > srcALen, output pointer is made to point to the end of the output buffer */
+ /* and the destination pointer modifier, inc is set to -1 */
+ /* If srcALen > srcBLen, zero pad has to be done to srcB to make the two inputs of same length */
+ /* But to improve the performance,
+ * we include zeroes in the output instead of zero padding either of the the inputs*/
+ /* If srcALen > srcBLen,
+ * (srcALen - srcBLen) zeroes has to included in the starting of the output buffer */
+ /* If srcALen < srcBLen,
+ * (srcALen - srcBLen) zeroes has to included in the ending of the output buffer */
+ if(srcALen >= srcBLen)
+ {
+ /* Initialization of inputA pointer */
+ pIn1 = (pSrcA);
+
+ /* Initialization of inputB pointer */
+ pIn2 = (pSrcB);
+
+ /* Number of output samples is calculated */
+ outBlockSize = (2u * srcALen) - 1u;
+
+ /* When srcALen > srcBLen, zero padding is done to srcB
+ * to make their lengths equal.
+ * Instead, (outBlockSize - (srcALen + srcBLen - 1))
+ * number of output samples are made zero */
+ j = outBlockSize - (srcALen + (srcBLen - 1u));
+
+ /* Updating the pointer position to non zero value */
+ pOut += j;
+
+ }
+ else
+ {
+ /* Initialization of inputA pointer */
+ pIn1 = (pSrcB);
+
+ /* Initialization of inputB pointer */
+ pIn2 = (pSrcA);
+
+ /* srcBLen is always considered as shorter or equal to srcALen */
+ j = srcBLen;
+ srcBLen = srcALen;
+ srcALen = j;
+
+ /* CORR(x, y) = Reverse order(CORR(y, x)) */
+ /* Hence set the destination pointer to point to the last output sample */
+ pOut = pDst + ((srcALen + srcBLen) - 2u);
+
+ /* Destination address modifier is set to -1 */
+ inc = -1;
+
+ }
+
+
+ /* Copy (srcBLen) samples in scratch buffer */
+ k = srcBLen >> 2u;
+
+ /* First part of the processing with loop unrolling copies 4 data points at a time.
+ ** a second loop below copies for the remaining 1 to 3 samples. */
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner */
+ x4 = (q15_t) * pIn2++;
+ *pScr2++ = x4;
+ x4 = (q15_t) * pIn2++;
+ *pScr2++ = x4;
+ x4 = (q15_t) * pIn2++;
+ *pScr2++ = x4;
+ x4 = (q15_t) * pIn2++;
+ *pScr2++ = x4;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+ /* If the count is not a multiple of 4, copy remaining samples here.
+ ** No loop unrolling is used. */
+ k = srcBLen % 0x4u;
+
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner for remaining samples */
+ x4 = (q15_t) * pIn2++;
+ *pScr2++ = x4;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+ /* Fill (srcBLen - 1u) zeros in scratch buffer */
+ arm_fill_q15(0, pScr1, (srcBLen - 1u));
+
+ /* Update temporary scratch pointer */
+ pScr1 += (srcBLen - 1u);
+
+ /* Copy (srcALen) samples in scratch buffer */
+ k = srcALen >> 2u;
+
+ /* First part of the processing with loop unrolling copies 4 data points at a time.
+ ** a second loop below copies for the remaining 1 to 3 samples. */
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner */
+ x4 = (q15_t) * pIn1++;
+ *pScr1++ = x4;
+ x4 = (q15_t) * pIn1++;
+ *pScr1++ = x4;
+ x4 = (q15_t) * pIn1++;
+ *pScr1++ = x4;
+ x4 = (q15_t) * pIn1++;
+ *pScr1++ = x4;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+ /* If the count is not a multiple of 4, copy remaining samples here.
+ ** No loop unrolling is used. */
+ k = srcALen % 0x4u;
+
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner for remaining samples */
+ x4 = (q15_t) * pIn1++;
+ *pScr1++ = x4;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+#ifndef UNALIGNED_SUPPORT_DISABLE
+
+ /* Fill (srcBLen - 1u) zeros at end of scratch buffer */
+ arm_fill_q15(0, pScr1, (srcBLen - 1u));
+
+ /* Update pointer */
+ pScr1 += (srcBLen - 1u);
+
+#else
+
+/* Apply loop unrolling and do 4 Copies simultaneously. */
+ k = (srcBLen - 1u) >> 2u;
+
+ /* First part of the processing with loop unrolling copies 4 data points at a time.
+ ** a second loop below copies for the remaining 1 to 3 samples. */
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner */
+ *pScr1++ = 0;
+ *pScr1++ = 0;
+ *pScr1++ = 0;
+ *pScr1++ = 0;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+ /* If the count is not a multiple of 4, copy remaining samples here.
+ ** No loop unrolling is used. */
+ k = (srcBLen - 1u) % 0x4u;
+
+ while(k > 0u)
+ {
+ /* copy second buffer in reversal manner for remaining samples */
+ *pScr1++ = 0;
+
+ /* Decrement the loop counter */
+ k--;
+ }
+
+#endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
+
+ /* Temporary pointer for second sequence */
+ py = pScratch2;
+
+ /* Initialization of pScr2 pointer */
+ pScr2 = pScratch2;
+
+ /* Actual correlation process starts here */
+ blkCnt = (srcALen + srcBLen - 1u) >> 2;
+
+ while(blkCnt > 0)
+ {
+ /* Initialze temporary scratch pointer as scratch1 */
+ pScr1 = pScratch1;
+
+ /* Clear Accumlators */
+ acc0 = 0;
+ acc1 = 0;
+ acc2 = 0;
+ acc3 = 0;
+
+ /* Read two samples from scratch1 buffer */
+ x1 = *__SIMD32(pScr1)++;
+
+ /* Read next two samples from scratch1 buffer */
+ x2 = *__SIMD32(pScr1)++;
+
+ tapCnt = (srcBLen) >> 2u;
+
+ while(tapCnt > 0u)
+ {
+
+ /* Read four samples from smaller buffer */
+ y1 = _SIMD32_OFFSET(pScr2);
+
+ /* multiply and accumlate */
+ acc0 = __SMLAD(x1, y1, acc0);
+ acc2 = __SMLAD(x2, y1, acc2);
+
+ /* pack input data */
+#ifndef ARM_MATH_BIG_ENDIAN
+ x3 = __PKHBT(x2, x1, 0);
+#else
+ x3 = __PKHBT(x1, x2, 0);
+#endif
+
+ /* multiply and accumlate */
+ acc1 = __SMLADX(x3, y1, acc1);
+
+ /* Read next two samples from scratch1 buffer */
+ x1 = *__SIMD32(pScr1)++;
+
+ /* pack input data */
+#ifndef ARM_MATH_BIG_ENDIAN
+ x3 = __PKHBT(x1, x2, 0);
+#else
+ x3 = __PKHBT(x2, x1, 0);
+#endif
+
+ acc3 = __SMLADX(x3, y1, acc3);
+
+ /* Read four samples from smaller buffer */
+ y1 = _SIMD32_OFFSET(pScr2 + 2u);
+
+ acc0 = __SMLAD(x2, y1, acc0);
+
+ acc2 = __SMLAD(x1, y1, acc2);
+
+ acc1 = __SMLADX(x3, y1, acc1);
+
+ x2 = *__SIMD32(pScr1)++;
+
+#ifndef ARM_MATH_BIG_ENDIAN
+ x3 = __PKHBT(x2, x1, 0);
+#else
+ x3 = __PKHBT(x1, x2, 0);
+#endif
+
+ acc3 = __SMLADX(x3, y1, acc3);
+
+ pScr2 += 4u;
+
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+
+
+ /* Update scratch pointer for remaining samples of smaller length sequence */
+ pScr1 -= 4u;
+
+
+ /* apply same above for remaining samples of smaller length sequence */
+ tapCnt = (srcBLen) & 3u;
+
+ while(tapCnt > 0u)
+ {
+
+ /* accumlate the results */
+ acc0 += (*pScr1++ * *pScr2);
+ acc1 += (*pScr1++ * *pScr2);
+ acc2 += (*pScr1++ * *pScr2);
+ acc3 += (*pScr1++ * *pScr2++);
+
+ pScr1 -= 3u;
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+ blkCnt--;
+
+ /* Store the result in the accumulator in the destination buffer. */
+ *pOut = (q7_t) (__SSAT(acc0 >> 7u, 8));
+ pOut += inc;
+ *pOut = (q7_t) (__SSAT(acc1 >> 7u, 8));
+ pOut += inc;
+ *pOut = (q7_t) (__SSAT(acc2 >> 7u, 8));
+ pOut += inc;
+ *pOut = (q7_t) (__SSAT(acc3 >> 7u, 8));
+ pOut += inc;
+
+ /* Initialization of inputB pointer */
+ pScr2 = py;
+
+ pScratch1 += 4u;
+
+ }
+
+
+ blkCnt = (srcALen + srcBLen - 1u) & 0x3;
+
+ /* Calculate correlation for remaining samples of Bigger length sequence */
+ while(blkCnt > 0)
+ {
+ /* Initialze temporary scratch pointer as scratch1 */
+ pScr1 = pScratch1;
+
+ /* Clear Accumlators */
+ acc0 = 0;
+
+ tapCnt = (srcBLen) >> 1u;
+
+ while(tapCnt > 0u)
+ {
+ acc0 += (*pScr1++ * *pScr2++);
+ acc0 += (*pScr1++ * *pScr2++);
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+ tapCnt = (srcBLen) & 1u;
+
+ /* apply same above for remaining samples of smaller length sequence */
+ while(tapCnt > 0u)
+ {
+
+ /* accumlate the results */
+ acc0 += (*pScr1++ * *pScr2++);
+
+ /* Decrement the loop counter */
+ tapCnt--;
+ }
+
+ blkCnt--;
+
+ /* Store the result in the accumulator in the destination buffer. */
+ *pOut = (q7_t) (__SSAT(acc0 >> 7u, 8));
+
+ pOut += inc;
+
+ /* Initialization of inputB pointer */
+ pScr2 = py;
+
+ pScratch1 += 1u;
+
+ }
+
+}
+
+/**
+ * @} end of Corr group
+ */
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