diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/SupportFunctions/arm_float_to_q15.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/SupportFunctions/arm_float_to_q15.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/SupportFunctions/arm_float_to_q15.c b/Drivers/CMSIS/DSP/Source/SupportFunctions/arm_float_to_q15.c new file mode 100644 index 0000000..a3c8bb2 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/SupportFunctions/arm_float_to_q15.c @@ -0,0 +1,244 @@ +/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_float_to_q15.c
+ * Description: Converts the elements of the floating-point vector to Q15 vector
+ *
+ * $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 groupSupport
+ */
+
+/**
+ @addtogroup float_to_x
+ @{
+ */
+
+/**
+ @brief Converts the elements of the floating-point vector to Q15 vector.
+ @param[in] pSrc points to the floating-point input vector
+ @param[out] pDst points to the Q15 output vector
+ @param[in] blockSize number of samples in each vector
+ @return none
+
+ @par Details
+ The equation used for the conversion process is:
+ <pre>
+ pDst[n] = (q15_t)(pSrc[n] * 32768); 0 <= n < blockSize.
+ </pre>
+
+ @par Scaling and Overflow Behavior
+ The function uses saturating arithmetic.
+ Results outside of the allowable Q15 range [0x8000 0x7FFF] are saturated.
+
+ @note
+ In order to apply rounding, the library should be rebuilt with the ROUNDING macro
+ defined in the preprocessor section of project options.
+ */
+#if defined(ARM_MATH_NEON_EXPERIMENTAL)
+void arm_float_to_q15(
+ const float32_t * pSrc,
+ q15_t * pDst,
+ uint32_t blockSize)
+{
+ const float32_t *pIn = pSrc; /* Src pointer */
+ uint32_t blkCnt; /* loop counter */
+
+ float32_t in;
+ float32x4_t inV;
+ #ifdef ARM_MATH_ROUNDING
+ float32x4_t zeroV = vdupq_n_f32(0.0f);
+ float32x4_t pHalf = vdupq_n_f32(0.5f / 32768.0f);
+ float32x4_t mHalf = vdupq_n_f32(-0.5f / 32768.0f);
+ float32x4_t r;
+ uint32x4_t cmp;
+ #endif
+
+ int32x4_t cvt;
+ int16x4_t outV;
+
+ blkCnt = blockSize >> 2U;
+
+ /* Compute 4 outputs at a time.
+ ** a second loop below computes the remaining 1 to 3 samples. */
+ while (blkCnt > 0U)
+ {
+
+#ifdef ARM_MATH_ROUNDING
+ /* C = A * 32768 */
+ /* Convert from float to q15 and then store the results in the destination buffer */
+ inV = vld1q_f32(pIn);
+ cmp = vcgtq_f32(inV,zeroV);
+ r = vbslq_f32(cmp,pHalf,mHalf);
+ inV = vaddq_f32(inV, r);
+
+ pIn += 4;
+
+ cvt = vcvtq_n_s32_f32(inV,15);
+ outV = vqmovn_s32(cvt);
+
+ vst1_s16(pDst, outV);
+ pDst += 4;
+
+#else
+
+ /* C = A * 32768 */
+ /* Convert from float to q15 and then store the results in the destination buffer */
+ inV = vld1q_f32(pIn);
+
+ cvt = vcvtq_n_s32_f32(inV,15);
+ outV = vqmovn_s32(cvt);
+
+ vst1_s16(pDst, outV);
+ pDst += 4;
+ pIn += 4;
+
+#endif /* #ifdef ARM_MATH_ROUNDING */
+
+ /* 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 & 3;
+
+ while (blkCnt > 0U)
+ {
+
+#ifdef ARM_MATH_ROUNDING
+ /* C = A * 32768 */
+ /* Convert from float to q15 and then store the results in the destination buffer */
+ in = *pIn++;
+ in = (in * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+#else
+
+ /* C = A * 32768 */
+ /* Convert from float to q15 and then store the results in the destination buffer */
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+
+#endif /* #ifdef ARM_MATH_ROUNDING */
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+}
+#else
+void arm_float_to_q15(
+ const float32_t * pSrc,
+ q15_t * pDst,
+ uint32_t blockSize)
+{
+ uint32_t blkCnt; /* Loop counter */
+ const float32_t *pIn = pSrc; /* Source pointer */
+
+#ifdef ARM_MATH_ROUNDING
+ float32_t in;
+#endif /* #ifdef ARM_MATH_ROUNDING */
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+ /* Loop unrolling: Compute 4 outputs at a time */
+ blkCnt = blockSize >> 2U;
+
+ while (blkCnt > 0U)
+ {
+ /* C = A * 32768 */
+
+ /* convert from float to Q15 and store result in destination buffer */
+#ifdef ARM_MATH_ROUNDING
+
+ in = (*pIn++ * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+ in = (*pIn++ * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+ in = (*pIn++ * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+ in = (*pIn++ * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+#else
+
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+
+#endif /* #ifdef ARM_MATH_ROUNDING */
+
+ /* 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) */
+
+ while (blkCnt > 0U)
+ {
+ /* C = A * 32768 */
+
+ /* convert from float to Q15 and store result in destination buffer */
+#ifdef ARM_MATH_ROUNDING
+
+ in = (*pIn++ * 32768.0f);
+ in += in > 0.0f ? 0.5f : -0.5f;
+ *pDst++ = (q15_t) (__SSAT((q31_t) (in), 16));
+
+#else
+
+ /* C = A * 32768 */
+ /* Convert from float to q15 and then store the results in the destination buffer */
+ *pDst++ = (q15_t) __SSAT((q31_t) (*pIn++ * 32768.0f), 16);
+
+#endif /* #ifdef ARM_MATH_ROUNDING */
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+
+}
+#endif /* #if defined(ARM_MATH_NEON) */
+
+/**
+ @} end of float_to_x group
+ */
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