diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_scale_q31.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_scale_q31.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_scale_q31.c b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_scale_q31.c new file mode 100644 index 0000000..52821ed --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_scale_q31.c @@ -0,0 +1,191 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_scale_q31.c
+ * Description: Multiplies a Q31 vector by a scalar
+ *
+ * $Date: 18. March 2019
+ * $Revision: V1.6.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2019 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 groupMath
+ */
+
+/**
+ @addtogroup BasicScale
+ @{
+ */
+
+/**
+ @brief Multiplies a Q31 vector by a scalar.
+ @param[in] pSrc points to the input vector
+ @param[in] scaleFract fractional portion of the scale value
+ @param[in] shift number of bits to shift the result by
+ @param[out] pDst points to the output vector
+ @param[in] blockSize number of samples in each vector
+ @return none
+
+ @par Scaling and Overflow Behavior
+ The input data <code>*pSrc</code> and <code>scaleFract</code> are in 1.31 format.
+ These are multiplied to yield a 2.62 intermediate result and this is shifted with saturation to 1.31 format.
+ */
+
+void arm_scale_q31(
+ const q31_t *pSrc,
+ q31_t scaleFract,
+ int8_t shift,
+ q31_t *pDst,
+ uint32_t blockSize)
+{
+ uint32_t blkCnt; /* Loop counter */
+ q31_t in, out; /* Temporary variables */
+ int8_t kShift = shift + 1; /* Shift to apply after scaling */
+ int8_t sign = (kShift & 0x80);
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+ /* Loop unrolling: Compute 4 outputs at a time */
+ blkCnt = blockSize >> 2U;
+
+ if (sign == 0U)
+ {
+ while (blkCnt > 0U)
+ {
+ /* C = A * scale */
+
+ /* Scale input and store result in destination buffer. */
+ in = *pSrc++; /* read input from source */
+ in = ((q63_t) in * scaleFract) >> 32; /* multiply input with scaler value */
+ out = in << kShift; /* apply shifting */
+ if (in != (out >> kShift)) /* saturate the result */
+ out = 0x7FFFFFFF ^ (in >> 31);
+ *pDst++ = out; /* Store result destination */
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in << kShift;
+ if (in != (out >> kShift))
+ out = 0x7FFFFFFF ^ (in >> 31);
+ *pDst++ = out;
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in << kShift;
+ if (in != (out >> kShift))
+ out = 0x7FFFFFFF ^ (in >> 31);
+ *pDst++ = out;
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in << kShift;
+ if (in != (out >> kShift))
+ out = 0x7FFFFFFF ^ (in >> 31);
+ *pDst++ = out;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+ }
+ else
+ {
+ while (blkCnt > 0U)
+ {
+ /* C = A * scale */
+
+ /* Scale input and store result in destination buffer. */
+ in = *pSrc++; /* read four inputs from source */
+ in = ((q63_t) in * scaleFract) >> 32; /* multiply input with scaler value */
+ out = in >> -kShift; /* apply shifting */
+ *pDst++ = out; /* Store result destination */
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in >> -kShift;
+ *pDst++ = out;
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in >> -kShift;
+ *pDst++ = out;
+
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in >> -kShift;
+ *pDst++ = out;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+ }
+
+ /* Loop unrolling: Compute remaining outputs */
+ blkCnt = blockSize % 0x4U;
+
+#else
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
+
+ if (sign == 0U)
+ {
+ while (blkCnt > 0U)
+ {
+ /* C = A * scale */
+
+ /* Scale input and store result in destination buffer. */
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in << kShift;
+ if (in != (out >> kShift))
+ out = 0x7FFFFFFF ^ (in >> 31);
+ *pDst++ = out;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+ }
+ else
+ {
+ while (blkCnt > 0U)
+ {
+ /* C = A * scale */
+
+ /* Scale input and store result in destination buffer. */
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+ out = in >> -kShift;
+ *pDst++ = out;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+ }
+
+}
+
+/**
+ @} end of BasicScale group
+ */
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