/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_float_to_q7.c * Description: Converts the elements of the floating-point vector to Q7 vector * * $Date: 23 April 2021 * $Revision: V1.9.0 * * Target Processor: Cortex-M and Cortex-A cores * -------------------------------------------------------------------- */ /* * Copyright (C) 2010-2021 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 "dsp/support_functions.h" /** @ingroup groupSupport */ /** @addtogroup float_to_x @{ */ /** * @brief Converts the elements of the floating-point vector to Q7 vector. * @param[in] *pSrc points to the floating-point input vector * @param[out] *pDst points to the Q7 output vector * @param[in] blockSize length of the input vector * @return none. * *\par Description: * \par * The equation used for the conversion process is: *
 * 	pDst[n] = (q7_t)(pSrc[n] * 128);   0 <= n < blockSize.
 * 
* \par Scaling and Overflow Behavior: * \par * The function uses saturating arithmetic. * Results outside of the allowable Q7 range [0x80 0x7F] will be 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_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) void arm_float_to_q7( const float32_t * pSrc, q7_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* loop counters */ float32_t maxQ = powf(2.0, 7); f32x4x4_t tmp; q15x8_t evVec, oddVec; q7x16_t vecDst; float32_t const *pSrcVec; #ifdef ARM_MATH_ROUNDING float32_t in; #endif pSrcVec = (float32_t const *) pSrc; blkCnt = blockSize >> 4; while (blkCnt > 0U) { tmp = vld4q(pSrcVec); pSrcVec += 16; /* * C = A * 128.0 * convert from float to q7 and then store the results in the destination buffer */ tmp.val[0] = vmulq(tmp.val[0], maxQ); tmp.val[1] = vmulq(tmp.val[1], maxQ); tmp.val[2] = vmulq(tmp.val[2], maxQ); tmp.val[3] = vmulq(tmp.val[3], maxQ); /* * convert and pack evens */ evVec = vqmovnbq(evVec, vcvtaq_s32_f32(tmp.val[0])); evVec = vqmovntq(evVec, vcvtaq_s32_f32(tmp.val[2])); /* * convert and pack odds */ oddVec = vqmovnbq(oddVec, vcvtaq_s32_f32(tmp.val[1])); oddVec = vqmovntq(oddVec, vcvtaq_s32_f32(tmp.val[3])); /* * merge */ vecDst = vqmovnbq(vecDst, evVec); vecDst = vqmovntq(vecDst, oddVec); vst1q(pDst, vecDst); pDst += 16; /* * Decrement the blockSize loop counter */ blkCnt--; } blkCnt = blockSize & 0xF; while (blkCnt > 0U) { /* C = A * 128 */ /* Convert from float to q7 and store result in destination buffer */ #ifdef ARM_MATH_ROUNDING in = (*pSrcVec++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); #else *pDst++ = (q7_t) __SSAT((q31_t) (*pSrcVec++ * 128.0f), 8); #endif /* #ifdef ARM_MATH_ROUNDING */ /* Decrement loop counter */ blkCnt--; } } #else #if defined(ARM_MATH_NEON) void arm_float_to_q7( const float32_t * pSrc, q7_t * pDst, uint32_t blockSize) { const float32_t *pIn = pSrc; /* Src pointer */ uint32_t blkCnt; /* loop counter */ float32x4_t inV; #ifdef ARM_MATH_ROUNDING float32_t in; float32x4_t zeroV = vdupq_n_f32(0.0f); float32x4_t pHalf = vdupq_n_f32(0.5f / 128.0f); float32x4_t mHalf = vdupq_n_f32(-0.5f / 128.0f); float32x4_t r; uint32x4_t cmp; #endif int16x4_t cvt1,cvt2; int8x8_t outV; blkCnt = blockSize >> 3U; /* Compute 8 outputs at a time. ** a second loop below computes the remaining 1 to 7 samples. */ while (blkCnt > 0U) { #ifdef ARM_MATH_ROUNDING /* C = A * 128 */ /* Convert from float to q7 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); cvt1 = vqmovn_s32(vcvtq_n_s32_f32(inV,7)); pIn += 4; inV = vld1q_f32(pIn); cmp = vcgtq_f32(inV,zeroV); r = vbslq_f32(cmp,pHalf,mHalf); inV = vaddq_f32(inV, r); cvt2 = vqmovn_s32(vcvtq_n_s32_f32(inV,7)); pIn += 4; outV = vqmovn_s16(vcombine_s16(cvt1,cvt2)); vst1_s8(pDst, outV); pDst += 8; #else /* C = A * 128 */ /* Convert from float to q7 and then store the results in the destination buffer */ inV = vld1q_f32(pIn); cvt1 = vqmovn_s32(vcvtq_n_s32_f32(inV,7)); pIn += 4; inV = vld1q_f32(pIn); cvt2 = vqmovn_s32(vcvtq_n_s32_f32(inV,7)); pIn += 4; outV = vqmovn_s16(vcombine_s16(cvt1,cvt2)); vst1_s8(pDst, outV); pDst += 8; #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 & 7; while (blkCnt > 0U) { #ifdef ARM_MATH_ROUNDING /* C = A * 128 */ /* Convert from float to q7 and then store the results in the destination buffer */ in = *pIn++; in = (in * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); #else /* C = A * 128 */ /* Convert from float to q7 and then store the results in the destination buffer */ *pDst++ = __SSAT((q31_t) (*pIn++ * 128.0f), 8); #endif /* #ifdef ARM_MATH_ROUNDING */ /* Decrement the loop counter */ blkCnt--; } } #else void arm_float_to_q7( const float32_t * pSrc, q7_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 * 128 */ /* Convert from float to q7 and store result in destination buffer */ #ifdef ARM_MATH_ROUNDING in = (*pIn++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); in = (*pIn++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); in = (*pIn++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); in = (*pIn++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); #else *pDst++ = __SSAT((q31_t) (*pIn++ * 128.0f), 8); *pDst++ = __SSAT((q31_t) (*pIn++ * 128.0f), 8); *pDst++ = __SSAT((q31_t) (*pIn++ * 128.0f), 8); *pDst++ = __SSAT((q31_t) (*pIn++ * 128.0f), 8); #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 * 128 */ /* Convert from float to q7 and store result in destination buffer */ #ifdef ARM_MATH_ROUNDING in = (*pIn++ * 128); in += in > 0.0f ? 0.5f : -0.5f; *pDst++ = (q7_t) (__SSAT((q15_t) (in), 8)); #else *pDst++ = (q7_t) __SSAT((q31_t) (*pIn++ * 128.0f), 8); #endif /* #ifdef ARM_MATH_ROUNDING */ /* Decrement loop counter */ blkCnt--; } } #endif /* #if defined(ARM_MATH_NEON) */ #endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */ /** @} end of float_to_x group */