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authorAli Labbene <ali.labbene@st.com>2019-12-11 08:59:21 +0100
committerAli Labbene <ali.labbene@st.com>2019-12-16 16:35:24 +0100
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Official ARM version: v5.4.0
Add CMSIS V5.4.0, please refer to index.html available under \docs folder. Note: content of \CMSIS\Core\Include has been copied under \Include to keep the same structure used in existing projects, and thus avoid projects mass update Note: the following components have been removed from ARM original delivery (as not used in ST packages) - CMSIS_EW2018.pdf - .gitattributes - .gitignore - \Device - \CMSIS - \CoreValidation - \DAP - \Documentation - \DoxyGen - \Driver - \Pack - \RTOS\CMSIS_RTOS_Tutorial.pdf - \RTOS\RTX - \RTOS\Template - \RTOS2\RTX - \Utilities - All ARM/GCC projects files are deleted from \DSP, \RTOS and \RTOS2 Change-Id: Ia026c3f0f0d016627a4fb5a9032852c33d24b4d3
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+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_scale_q15.c
+ * Description: Multiplies a Q15 vector by a scalar
+ *
+ * $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 groupMath
+ */
+
+/**
+ * @addtogroup scale
+ * @{
+ */
+
+/**
+ * @brief Multiplies a Q15 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 the vector
+ * @return none.
+ *
+ * <b>Scaling and Overflow Behavior:</b>
+ * \par
+ * The input data <code>*pSrc</code> and <code>scaleFract</code> are in 1.15 format.
+ * These are multiplied to yield a 2.30 intermediate result and this is shifted with saturation to 1.15 format.
+ */
+
+
+void arm_scale_q15(
+ q15_t * pSrc,
+ q15_t scaleFract,
+ int8_t shift,
+ q15_t * pDst,
+ uint32_t blockSize)
+{
+ int8_t kShift = 15 - shift; /* shift to apply after scaling */
+ uint32_t blkCnt; /* loop counter */
+
+#if defined (ARM_MATH_DSP)
+
+/* Run the below code for Cortex-M4 and Cortex-M3 */
+ q15_t in1, in2, in3, in4;
+ q31_t inA1, inA2; /* Temporary variables */
+ q31_t out1, out2, out3, out4;
+
+
+ /*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)
+ {
+ /* Reading 2 inputs from memory */
+ inA1 = *__SIMD32(pSrc)++;
+ inA2 = *__SIMD32(pSrc)++;
+
+ /* C = A * scale */
+ /* Scale the inputs and then store the 2 results in the destination buffer
+ * in single cycle by packing the outputs */
+ out1 = (q31_t) ((q15_t) (inA1 >> 16) * scaleFract);
+ out2 = (q31_t) ((q15_t) inA1 * scaleFract);
+ out3 = (q31_t) ((q15_t) (inA2 >> 16) * scaleFract);
+ out4 = (q31_t) ((q15_t) inA2 * scaleFract);
+
+ /* apply shifting */
+ out1 = out1 >> kShift;
+ out2 = out2 >> kShift;
+ out3 = out3 >> kShift;
+ out4 = out4 >> kShift;
+
+ /* saturate the output */
+ in1 = (q15_t) (__SSAT(out1, 16));
+ in2 = (q15_t) (__SSAT(out2, 16));
+ in3 = (q15_t) (__SSAT(out3, 16));
+ in4 = (q15_t) (__SSAT(out4, 16));
+
+ /* store the result to destination */
+ *__SIMD32(pDst)++ = __PKHBT(in2, in1, 16);
+ *__SIMD32(pDst)++ = __PKHBT(in4, in3, 16);
+
+ /* 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 * scale */
+ /* Scale the input and then store the result in the destination buffer. */
+ *pDst++ = (q15_t) (__SSAT(((*pSrc++) * scaleFract) >> kShift, 16));
+
+ /* 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 * scale */
+ /* Scale the input and then store the result in the destination buffer. */
+ *pDst++ = (q15_t) (__SSAT(((q31_t) * pSrc++ * scaleFract) >> kShift, 16));
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+#endif /* #if defined (ARM_MATH_DSP) */
+
+}
+
+/**
+ * @} end of scale group
+ */