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authorrihab kouki <rihab.kouki@st.com>2020-07-28 11:24:49 +0100
committerrihab kouki <rihab.kouki@st.com>2020-07-28 11:24:49 +0100
commit96d6da4e252b06dcfdc041e7df23e86161c33007 (patch)
treea262f59bb1db7ec7819acae435f5049cbe5e2354 /DSP/Source/BasicMathFunctions/arm_shift_q15.c
parent9f95ff5b6ba01db09552b84a0ab79607060a2666 (diff)
downloadst-cmsis-core-lowfat-master.tar.gz
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Official ARM version: v5.6.0HEADmaster
Diffstat (limited to 'DSP/Source/BasicMathFunctions/arm_shift_q15.c')
-rw-r--r--DSP/Source/BasicMathFunctions/arm_shift_q15.c213
1 files changed, 89 insertions, 124 deletions
diff --git a/DSP/Source/BasicMathFunctions/arm_shift_q15.c b/DSP/Source/BasicMathFunctions/arm_shift_q15.c
index d2cd037..8a15155 100644
--- a/DSP/Source/BasicMathFunctions/arm_shift_q15.c
+++ b/DSP/Source/BasicMathFunctions/arm_shift_q15.c
@@ -3,13 +3,13 @@
* Title: arm_shift_q15.c
* Description: Shifts the elements of a Q15 vector by a specified number of bits
*
- * $Date: 27. January 2017
- * $Revision: V.1.5.1
+ * $Date: 18. March 2019
+ * $Revision: V1.6.0
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
- * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
+ * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*
@@ -29,208 +29,173 @@
#include "arm_math.h"
/**
- * @ingroup groupMath
+ @ingroup groupMath
*/
/**
- * @addtogroup shift
- * @{
+ @addtogroup BasicShift
+ @{
*/
/**
- * @brief Shifts the elements of a Q15 vector a specified number of bits.
- * @param[in] *pSrc points to the input vector
- * @param[in] shiftBits number of bits to shift. A positive value shifts left; a negative value shifts right.
- * @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 function uses saturating arithmetic.
- * Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated.
+ @brief Shifts the elements of a Q15 vector a specified number of bits
+ @param[in] pSrc points to the input vector
+ @param[in] shiftBits number of bits to shift. A positive value shifts left; a negative value shifts right.
+ @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 function uses saturating arithmetic.
+ Results outside of the allowable Q15 range [0x8000 0x7FFF] are saturated.
*/
void arm_shift_q15(
- q15_t * pSrc,
- int8_t shiftBits,
- q15_t * pDst,
- uint32_t blockSize)
+ const q15_t * pSrc,
+ int8_t shiftBits,
+ q15_t * pDst,
+ uint32_t blockSize)
{
- uint32_t blkCnt; /* loop counter */
- uint8_t sign; /* Sign of shiftBits */
-
-#if defined (ARM_MATH_DSP)
-
-/* Run the below code for Cortex-M4 and Cortex-M3 */
+ uint32_t blkCnt; /* Loop counter */
+ uint8_t sign = (shiftBits & 0x80); /* Sign of shiftBits */
- q15_t in1, in2; /* Temporary variables */
+#if defined (ARM_MATH_LOOPUNROLL)
+#if defined (ARM_MATH_DSP)
+ q15_t in1, in2; /* Temporary input variables */
+#endif
- /*loop Unrolling */
+ /* Loop unrolling: Compute 4 outputs at a time */
blkCnt = blockSize >> 2U;
- /* Getting the sign of shiftBits */
- sign = (shiftBits & 0x80);
-
/* If the shift value is positive then do right shift else left shift */
if (sign == 0U)
{
- /* 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)
{
- /* Read 2 inputs */
- in1 = *pSrc++;
- in2 = *pSrc++;
/* C = A << shiftBits */
- /* Shift the inputs and then store the results in the destination buffer. */
-#ifndef ARM_MATH_BIG_ENDIAN
- *__SIMD32(pDst)++ = __PKHBT(__SSAT((in1 << shiftBits), 16),
- __SSAT((in2 << shiftBits), 16), 16);
+#if defined (ARM_MATH_DSP)
+ /* read 2 samples from source */
+ in1 = *pSrc++;
+ in2 = *pSrc++;
+ /* Shift the inputs and then store the results in the destination buffer. */
+#ifndef ARM_MATH_BIG_ENDIAN
+ write_q15x2_ia (&pDst, __PKHBT(__SSAT((in1 << shiftBits), 16),
+ __SSAT((in2 << shiftBits), 16), 16));
#else
+ write_q15x2_ia (&pDst, __PKHBT(__SSAT((in2 << shiftBits), 16),
+ __SSAT((in1 << shiftBits), 16), 16));
+#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
- *__SIMD32(pDst)++ = __PKHBT(__SSAT((in2 << shiftBits), 16),
- __SSAT((in1 << shiftBits), 16), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
+ /* read 2 samples from source */
in1 = *pSrc++;
in2 = *pSrc++;
-#ifndef ARM_MATH_BIG_ENDIAN
-
- *__SIMD32(pDst)++ = __PKHBT(__SSAT((in1 << shiftBits), 16),
- __SSAT((in2 << shiftBits), 16), 16);
-
+#ifndef ARM_MATH_BIG_ENDIAN
+ write_q15x2_ia (&pDst, __PKHBT(__SSAT((in1 << shiftBits), 16),
+ __SSAT((in2 << shiftBits), 16), 16));
#else
+ write_q15x2_ia (&pDst, __PKHBT(__SSAT((in2 << shiftBits), 16),
+ __SSAT((in1 << shiftBits), 16), 16));
+#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
- *__SIMD32(pDst)++ = __PKHBT(__SSAT((in2 << shiftBits), 16),
- __SSAT((in1 << shiftBits), 16), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
- /* 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 << shiftBits */
- /* Shift and then store the results in the destination buffer. */
- *pDst++ = __SSAT((*pSrc++ << shiftBits), 16);
+#else
+ *pDst++ = __SSAT(((q31_t) *pSrc++ << shiftBits), 16);
+ *pDst++ = __SSAT(((q31_t) *pSrc++ << shiftBits), 16);
+ *pDst++ = __SSAT(((q31_t) *pSrc++ << shiftBits), 16);
+ *pDst++ = __SSAT(((q31_t) *pSrc++ << shiftBits), 16);
+#endif
- /* Decrement the loop counter */
+ /* Decrement loop counter */
blkCnt--;
}
}
else
{
- /* 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)
{
- /* Read 2 inputs */
+ /* C = A >> shiftBits */
+
+#if defined (ARM_MATH_DSP)
+ /* read 2 samples from source */
in1 = *pSrc++;
in2 = *pSrc++;
- /* C = A >> shiftBits */
/* Shift the inputs and then store the results in the destination buffer. */
-#ifndef ARM_MATH_BIG_ENDIAN
-
- *__SIMD32(pDst)++ = __PKHBT((in1 >> -shiftBits),
- (in2 >> -shiftBits), 16);
-
+#ifndef ARM_MATH_BIG_ENDIAN
+ write_q15x2_ia (&pDst, __PKHBT((in1 >> -shiftBits),
+ (in2 >> -shiftBits), 16));
#else
+ write_q15x2_ia (&pDst, __PKHBT((in2 >> -shiftBits),
+ (in1 >> -shiftBits), 16));
+#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
- *__SIMD32(pDst)++ = __PKHBT((in2 >> -shiftBits),
- (in1 >> -shiftBits), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
+ /* read 2 samples from source */
in1 = *pSrc++;
in2 = *pSrc++;
-#ifndef ARM_MATH_BIG_ENDIAN
-
- *__SIMD32(pDst)++ = __PKHBT((in1 >> -shiftBits),
- (in2 >> -shiftBits), 16);
-
+#ifndef ARM_MATH_BIG_ENDIAN
+ write_q15x2_ia (&pDst, __PKHBT((in1 >> -shiftBits),
+ (in2 >> -shiftBits), 16));
#else
+ write_q15x2_ia (&pDst, __PKHBT((in2 >> -shiftBits),
+ (in1 >> -shiftBits), 16));
+#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
- *__SIMD32(pDst)++ = __PKHBT((in2 >> -shiftBits),
- (in1 >> -shiftBits), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
- /* 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 >> shiftBits */
- /* Shift the inputs and then store the results in the destination buffer. */
+#else
+ *pDst++ = (*pSrc++ >> -shiftBits);
+ *pDst++ = (*pSrc++ >> -shiftBits);
+ *pDst++ = (*pSrc++ >> -shiftBits);
*pDst++ = (*pSrc++ >> -shiftBits);
+#endif
- /* Decrement the loop counter */
+ /* Decrement loop counter */
blkCnt--;
}
}
+ /* Loop unrolling: Compute remaining outputs */
+ blkCnt = blockSize % 0x4U;
+
#else
- /* Run the below code for Cortex-M0 */
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
- /* Getting the sign of shiftBits */
- sign = (shiftBits & 0x80);
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
/* If the shift value is positive then do right shift else left shift */
if (sign == 0U)
{
- /* Initialize blkCnt with number of samples */
- blkCnt = blockSize;
-
while (blkCnt > 0U)
{
/* C = A << shiftBits */
- /* Shift and then store the results in the destination buffer. */
- *pDst++ = __SSAT(((q31_t) * pSrc++ << shiftBits), 16);
- /* Decrement the loop counter */
+ /* Shift input and store result in destination buffer. */
+ *pDst++ = __SSAT(((q31_t) *pSrc++ << shiftBits), 16);
+
+ /* Decrement loop counter */
blkCnt--;
}
}
else
{
- /* Initialize blkCnt with number of samples */
- blkCnt = blockSize;
-
while (blkCnt > 0U)
{
/* C = A >> shiftBits */
- /* Shift the inputs and then store the results in the destination buffer. */
+
+ /* Shift input and store result in destination buffer. */
*pDst++ = (*pSrc++ >> -shiftBits);
- /* Decrement the loop counter */
+ /* Decrement loop counter */
blkCnt--;
}
}
-#endif /* #if defined (ARM_MATH_DSP) */
-
}
/**
- * @} end of shift group
+ @} end of BasicShift group
*/