Laxmi Kant Tiwari
CMSIS DSP Lib
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Diff: cmsis_dsp/BasicMathFunctions/arm_scale_q31.c
- Revision:
- 3:7a284390b0ce
- Parent:
- 2:da51fb522205
--- a/cmsis_dsp/BasicMathFunctions/arm_scale_q31.c Thu May 30 17:10:11 2013 +0100
+++ b/cmsis_dsp/BasicMathFunctions/arm_scale_q31.c Fri Nov 08 13:45:10 2013 +0000
@@ -1,62 +1,67 @@
-/* ----------------------------------------------------------------------
-* Copyright (C) 2010 ARM Limited. All rights reserved.
-*
-* $Date: 15. May 2012
-* $Revision: V1.1.0
-*
-* Project: CMSIS DSP Library
-* Title: arm_scale_q31.c
-*
-* Description: Multiplies a Q31 vector by a scalar.
-*
+/* ----------------------------------------------------------------------
+* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
+*
+* $Date: 17. January 2013
+* $Revision: V1.4.1
+*
+* Project: CMSIS DSP Library
+* Title: arm_scale_q31.c
+*
+* Description: Multiplies a Q31 vector by a scalar.
+*
* 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.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* - Redistributions of source code must retain the above copyright
+* notice, this list of conditions and the following disclaimer.
+* - Redistributions in binary form must reproduce the above copyright
+* notice, this list of conditions and the following disclaimer in
+* the documentation and/or other materials provided with the
+* distribution.
+* - Neither the name of ARM LIMITED nor the names of its contributors
+* may be used to endorse or promote products derived from this
+* software without specific prior written permission.
*
-* 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
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+* POSSIBILITY OF SUCH DAMAGE.
* -------------------------------------------------------------------- */
#include "arm_math.h"
-/**
- * @ingroup groupMath
+/**
+ * @ingroup groupMath
*/
-/**
- * @addtogroup scale
- * @{
+/**
+ * @addtogroup scale
+ * @{
*/
-/**
- * @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 the vector
- * @return none.
- *
- * <b>Scaling and Overflow Behavior:</b>
- * \par
- * 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.
+/**
+ * @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 the vector
+ * @return none.
+ *
+ * <b>Scaling and Overflow Behavior:</b>
+ * \par
+ * 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(
@@ -71,7 +76,7 @@
uint32_t blkCnt; /* loop counter */
q31_t in, out;
-#ifndef ARM_MATH_CM0
+#ifndef ARM_MATH_CM0_FAMILY
/* Run the below code for Cortex-M4 and Cortex-M3 */
@@ -84,7 +89,7 @@
if(sign == 0u)
{
- /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
+ /* 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)
{
@@ -138,9 +143,7 @@
}
else
{
- kShift = -kShift;
-
- /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
+ /* 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)
{
@@ -157,11 +160,11 @@
in4 = ((q63_t) in4 * scaleFract) >> 32;
/* apply shifting */
- out1 = in1 >> kShift;
- out2 = in2 >> kShift;
+ out1 = in1 >> -kShift;
+ out2 = in2 >> -kShift;
- out3 = in3 >> kShift;
- out4 = in4 >> kShift;
+ out3 = in3 >> -kShift;
+ out4 = in4 >> -kShift;
/* Store result destination */
*pDst = out1;
@@ -178,46 +181,59 @@
blkCnt--;
}
}
- /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
+ /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
** No loop unrolling is used. */
blkCnt = blockSize % 0x4u;
#else
/* Run the below code for Cortex-M0 */
- if(sign != 0u)
- kShift = -kShift;
/* Initialize blkCnt with number of samples */
blkCnt = blockSize;
-#endif /* #ifndef ARM_MATH_CM0 */
+#endif /* #ifndef ARM_MATH_CM0_FAMILY */
- while(blkCnt > 0u)
+ if(sign == 0)
{
- /* C = A * scale */
- /* Scale the input and then store the result in the destination buffer. */
- in = *pSrc++;
- in = ((q63_t) in * scaleFract) >> 32;
+ while(blkCnt > 0u)
+ {
+ /* C = A * scale */
+ /* Scale the input and then store the result in the destination buffer. */
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
+
+ out = in << kShift;
+
+ if(in != (out >> kShift))
+ out = 0x7FFFFFFF ^ (in >> 31);
+
+ *pDst++ = out;
- if(sign == 0)
- {
- out = in << kShift;
- if(in != (out >> kShift))
- out = 0x7FFFFFFF ^ (in >> 31);
- }
- else
- {
- out = in >> kShift;
- }
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+ }
+ else
+ {
+ while(blkCnt > 0u)
+ {
+ /* C = A * scale */
+ /* Scale the input and then store the result in the destination buffer. */
+ in = *pSrc++;
+ in = ((q63_t) in * scaleFract) >> 32;
- *pDst++ = out;
+ out = in >> -kShift;
+
+ *pDst++ = out;
- /* Decrement the loop counter */
- blkCnt--;
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
}
}
-/**
- * @} end of scale group
+/**
+ * @} end of scale group
*/