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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/BasicMathFunctions/arm_sub_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/BasicMathFunctions/arm_sub_q7.c')
-rw-r--r-- | apps/mathlib/CMSIS/DSP_Lib/Source/BasicMathFunctions/arm_sub_q7.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/BasicMathFunctions/arm_sub_q7.c b/apps/mathlib/CMSIS/DSP_Lib/Source/BasicMathFunctions/arm_sub_q7.c new file mode 100644 index 000000000..adbc7d0c0 --- /dev/null +++ b/apps/mathlib/CMSIS/DSP_Lib/Source/BasicMathFunctions/arm_sub_q7.c @@ -0,0 +1,126 @@ +/* ----------------------------------------------------------------------
+* Copyright (C) 2010 ARM Limited. All rights reserved.
+*
+* $Date: 15. February 2012
+* $Revision: V1.1.0
+*
+* Project: CMSIS DSP Library
+* Title: arm_sub_q7.c
+*
+* Description: Q7 vector subtraction.
+*
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*
+* 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 0.0.7 2010/06/10
+* Misra-C changes done
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupMath
+ */
+
+/**
+ * @addtogroup BasicSub
+ * @{
+ */
+
+/**
+ * @brief Q7 vector subtraction.
+ * @param[in] *pSrcA points to the first input vector
+ * @param[in] *pSrcB points to the second input vector
+ * @param[out] *pDst points to the output vector
+ * @param[in] blockSize number of samples in each vector
+ * @return none.
+ *
+ * <b>Scaling and Overflow Behavior:</b>
+ * \par
+ * The function uses saturating arithmetic.
+ * Results outside of the allowable Q7 range [0x80 0x7F] will be saturated.
+ */
+
+void arm_sub_q7(
+ q7_t * pSrcA,
+ q7_t * pSrcB,
+ q7_t * pDst,
+ uint32_t blockSize)
+{
+ uint32_t blkCnt; /* loop counter */
+
+#ifndef ARM_MATH_CM0
+
+/* Run the below code for Cortex-M4 and Cortex-M3 */
+
+ /*loop Unrolling */
+ blkCnt = blockSize >> 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 = A - B */
+ /* Subtract and then store the results in the destination buffer 4 samples at a time. */
+ *__SIMD32(pDst)++ = __QSUB8(*__SIMD32(pSrcA)++, *__SIMD32(pSrcB)++);
+
+ /* Decrement the 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 % 0x4u;
+
+ while(blkCnt > 0u)
+ {
+ /* C = A - B */
+ /* Subtract and then store the result in the destination buffer. */
+ *pDst++ = __SSAT(*pSrcA++ - *pSrcB++, 8);
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+#else
+
+ /* Run the below code for Cortex-M0 */
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+ while(blkCnt > 0u)
+ {
+ /* C = A - B */
+ /* Subtract and then store the result in the destination buffer. */
+ *pDst++ = (q7_t) __SSAT((q15_t) * pSrcA++ - *pSrcB++, 8);
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+#endif /* #ifndef ARM_MATH_CM0 */
+
+
+}
+
+/**
+ * @} end of BasicSub group
+ */
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