/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_cfft_radix8_f16.c * Description: Radix-8 Decimation in Frequency CFFT & CIFFT Floating point processing function * * $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/transform_functions_f16.h" #if defined(ARM_FLOAT16_SUPPORTED) void arm_radix8_butterfly_f16( float16_t * pSrc, uint16_t fftLen, const float16_t * pCoef, uint16_t twidCoefModifier); /* ---------------------------------------------------------------------- * Internal helper function used by the FFTs * -------------------------------------------------------------------- */ /** brief Core function for the floating-point CFFT butterfly process. param[in,out] pSrc points to the in-place buffer of floating-point data type. param[in] fftLen length of the FFT. param[in] pCoef points to the twiddle coefficient buffer. param[in] twidCoefModifier twiddle coefficient modifier that supports different size FFTs with the same twiddle factor table. return none */ ARM_DSP_ATTRIBUTE void arm_radix8_butterfly_f16( float16_t * pSrc, uint16_t fftLen, const float16_t * pCoef, uint16_t twidCoefModifier) { uint32_t ia1, ia2, ia3, ia4, ia5, ia6, ia7; uint32_t i1, i2, i3, i4, i5, i6, i7, i8; uint32_t id; uint32_t n1, n2, j; float16_t r1, r2, r3, r4, r5, r6, r7, r8; float16_t t1, t2; float16_t s1, s2, s3, s4, s5, s6, s7, s8; float16_t p1, p2, p3, p4; float16_t co2, co3, co4, co5, co6, co7, co8; float16_t si2, si3, si4, si5, si6, si7, si8; const float16_t C81 = 0.70710678118f16; n2 = fftLen; do { n1 = n2; n2 = n2 >> 3; i1 = 0; do { i2 = i1 + n2; i3 = i2 + n2; i4 = i3 + n2; i5 = i4 + n2; i6 = i5 + n2; i7 = i6 + n2; i8 = i7 + n2; r1 = (_Float16)pSrc[2 * i1] + (_Float16)pSrc[2 * i5]; r5 = (_Float16)pSrc[2 * i1] - (_Float16)pSrc[2 * i5]; r2 = (_Float16)pSrc[2 * i2] + (_Float16)pSrc[2 * i6]; r6 = (_Float16)pSrc[2 * i2] - (_Float16)pSrc[2 * i6]; r3 = (_Float16)pSrc[2 * i3] + (_Float16)pSrc[2 * i7]; r7 = (_Float16)pSrc[2 * i3] - (_Float16)pSrc[2 * i7]; r4 = (_Float16)pSrc[2 * i4] + (_Float16)pSrc[2 * i8]; r8 = (_Float16)pSrc[2 * i4] - (_Float16)pSrc[2 * i8]; t1 = (_Float16)r1 - (_Float16)r3; r1 = (_Float16)r1 + (_Float16)r3; r3 = (_Float16)r2 - (_Float16)r4; r2 = (_Float16)r2 + (_Float16)r4; pSrc[2 * i1] = (_Float16)r1 + (_Float16)r2; pSrc[2 * i5] = (_Float16)r1 - (_Float16)r2; r1 = (_Float16)pSrc[2 * i1 + 1] + (_Float16)pSrc[2 * i5 + 1]; s5 = (_Float16)pSrc[2 * i1 + 1] - (_Float16)pSrc[2 * i5 + 1]; r2 = (_Float16)pSrc[2 * i2 + 1] + (_Float16)pSrc[2 * i6 + 1]; s6 = (_Float16)pSrc[2 * i2 + 1] - (_Float16)pSrc[2 * i6 + 1]; s3 = (_Float16)pSrc[2 * i3 + 1] + (_Float16)pSrc[2 * i7 + 1]; s7 = (_Float16)pSrc[2 * i3 + 1] - (_Float16)pSrc[2 * i7 + 1]; r4 = (_Float16)pSrc[2 * i4 + 1] + (_Float16)pSrc[2 * i8 + 1]; s8 = (_Float16)pSrc[2 * i4 + 1] - (_Float16)pSrc[2 * i8 + 1]; t2 = (_Float16)r1 - (_Float16)s3; r1 = (_Float16)r1 + (_Float16)s3; s3 = (_Float16)r2 - (_Float16)r4; r2 = (_Float16)r2 + (_Float16)r4; pSrc[2 * i1 + 1] = (_Float16)r1 + (_Float16)r2; pSrc[2 * i5 + 1] = (_Float16)r1 - (_Float16)r2; pSrc[2 * i3] = (_Float16)t1 + (_Float16)s3; pSrc[2 * i7] = (_Float16)t1 - (_Float16)s3; pSrc[2 * i3 + 1] = (_Float16)t2 - (_Float16)r3; pSrc[2 * i7 + 1] = (_Float16)t2 + (_Float16)r3; r1 = ((_Float16)r6 - (_Float16)r8) * (_Float16)C81; r6 = ((_Float16)r6 + (_Float16)r8) * (_Float16)C81; r2 = ((_Float16)s6 - (_Float16)s8) * (_Float16)C81; s6 = ((_Float16)s6 + (_Float16)s8) * (_Float16)C81; t1 = (_Float16)r5 - (_Float16)r1; r5 = (_Float16)r5 + (_Float16)r1; r8 = (_Float16)r7 - (_Float16)r6; r7 = (_Float16)r7 + (_Float16)r6; t2 = (_Float16)s5 - (_Float16)r2; s5 = (_Float16)s5 + (_Float16)r2; s8 = (_Float16)s7 - (_Float16)s6; s7 = (_Float16)s7 + (_Float16)s6; pSrc[2 * i2] = (_Float16)r5 + (_Float16)s7; pSrc[2 * i8] = (_Float16)r5 - (_Float16)s7; pSrc[2 * i6] = (_Float16)t1 + (_Float16)s8; pSrc[2 * i4] = (_Float16)t1 - (_Float16)s8; pSrc[2 * i2 + 1] = (_Float16)s5 - (_Float16)r7; pSrc[2 * i8 + 1] = (_Float16)s5 + (_Float16)r7; pSrc[2 * i6 + 1] = (_Float16)t2 - (_Float16)r8; pSrc[2 * i4 + 1] = (_Float16)t2 + (_Float16)r8; i1 += n1; } while (i1 < fftLen); if (n2 < 8) break; ia1 = 0; j = 1; do { /* index calculation for the coefficients */ id = ia1 + twidCoefModifier; ia1 = id; ia2 = ia1 + id; ia3 = ia2 + id; ia4 = ia3 + id; ia5 = ia4 + id; ia6 = ia5 + id; ia7 = ia6 + id; co2 = pCoef[2 * ia1]; co3 = pCoef[2 * ia2]; co4 = pCoef[2 * ia3]; co5 = pCoef[2 * ia4]; co6 = pCoef[2 * ia5]; co7 = pCoef[2 * ia6]; co8 = pCoef[2 * ia7]; si2 = pCoef[2 * ia1 + 1]; si3 = pCoef[2 * ia2 + 1]; si4 = pCoef[2 * ia3 + 1]; si5 = pCoef[2 * ia4 + 1]; si6 = pCoef[2 * ia5 + 1]; si7 = pCoef[2 * ia6 + 1]; si8 = pCoef[2 * ia7 + 1]; i1 = j; do { /* index calculation for the input */ i2 = i1 + n2; i3 = i2 + n2; i4 = i3 + n2; i5 = i4 + n2; i6 = i5 + n2; i7 = i6 + n2; i8 = i7 + n2; r1 = (_Float16)pSrc[2 * i1] + (_Float16)pSrc[2 * i5]; r5 = (_Float16)pSrc[2 * i1] - (_Float16)pSrc[2 * i5]; r2 = (_Float16)pSrc[2 * i2] + (_Float16)pSrc[2 * i6]; r6 = (_Float16)pSrc[2 * i2] - (_Float16)pSrc[2 * i6]; r3 = (_Float16)pSrc[2 * i3] + (_Float16)pSrc[2 * i7]; r7 = (_Float16)pSrc[2 * i3] - (_Float16)pSrc[2 * i7]; r4 = (_Float16)pSrc[2 * i4] + (_Float16)pSrc[2 * i8]; r8 = (_Float16)pSrc[2 * i4] - (_Float16)pSrc[2 * i8]; t1 = (_Float16)r1 - (_Float16)r3; r1 = (_Float16)r1 + (_Float16)r3; r3 = (_Float16)r2 - (_Float16)r4; r2 = (_Float16)r2 + (_Float16)r4; pSrc[2 * i1] = (_Float16)r1 + (_Float16)r2; r2 = (_Float16)r1 - (_Float16)r2; s1 = (_Float16)pSrc[2 * i1 + 1] + (_Float16)pSrc[2 * i5 + 1]; s5 = (_Float16)pSrc[2 * i1 + 1] - (_Float16)pSrc[2 * i5 + 1]; s2 = (_Float16)pSrc[2 * i2 + 1] + (_Float16)pSrc[2 * i6 + 1]; s6 = (_Float16)pSrc[2 * i2 + 1] - (_Float16)pSrc[2 * i6 + 1]; s3 = (_Float16)pSrc[2 * i3 + 1] + (_Float16)pSrc[2 * i7 + 1]; s7 = (_Float16)pSrc[2 * i3 + 1] - (_Float16)pSrc[2 * i7 + 1]; s4 = (_Float16)pSrc[2 * i4 + 1] + (_Float16)pSrc[2 * i8 + 1]; s8 = (_Float16)pSrc[2 * i4 + 1] - (_Float16)pSrc[2 * i8 + 1]; t2 = (_Float16)s1 - (_Float16)s3; s1 = (_Float16)s1 + (_Float16)s3; s3 = (_Float16)s2 - (_Float16)s4; s2 = (_Float16)s2 + (_Float16)s4; r1 = (_Float16)t1 + (_Float16)s3; t1 = (_Float16)t1 - (_Float16)s3; pSrc[2 * i1 + 1] = (_Float16)s1 + (_Float16)s2; s2 = (_Float16)s1 - (_Float16)s2; s1 = (_Float16)t2 - (_Float16)r3; t2 = (_Float16)t2 + (_Float16)r3; p1 = (_Float16)co5 * (_Float16)r2; p2 = (_Float16)si5 * (_Float16)s2; p3 = (_Float16)co5 * (_Float16)s2; p4 = (_Float16)si5 * (_Float16)r2; pSrc[2 * i5] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i5 + 1] = (_Float16)p3 - (_Float16)p4; p1 = (_Float16)co3 * (_Float16)r1; p2 = (_Float16)si3 * (_Float16)s1; p3 = (_Float16)co3 * (_Float16)s1; p4 = (_Float16)si3 * (_Float16)r1; pSrc[2 * i3] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i3 + 1] = (_Float16)p3 - (_Float16)p4; p1 = (_Float16)co7 * (_Float16)t1; p2 = (_Float16)si7 * (_Float16)t2; p3 = (_Float16)co7 * (_Float16)t2; p4 = (_Float16)si7 * (_Float16)t1; pSrc[2 * i7] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i7 + 1] = (_Float16)p3 - (_Float16)p4; r1 = ((_Float16)r6 - (_Float16)r8) * (_Float16)C81; r6 = ((_Float16)r6 + (_Float16)r8) * (_Float16)C81; s1 = ((_Float16)s6 - (_Float16)s8) * (_Float16)C81; s6 = ((_Float16)s6 + (_Float16)s8) * (_Float16)C81; t1 = (_Float16)r5 - (_Float16)r1; r5 = (_Float16)r5 + (_Float16)r1; r8 = (_Float16)r7 - (_Float16)r6; r7 = (_Float16)r7 + (_Float16)r6; t2 = (_Float16)s5 - (_Float16)s1; s5 = (_Float16)s5 + (_Float16)s1; s8 = (_Float16)s7 - (_Float16)s6; s7 = (_Float16)s7 + (_Float16)s6; r1 = (_Float16)r5 + (_Float16)s7; r5 = (_Float16)r5 - (_Float16)s7; r6 = (_Float16)t1 + (_Float16)s8; t1 = (_Float16)t1 - (_Float16)s8; s1 = (_Float16)s5 - (_Float16)r7; s5 = (_Float16)s5 + (_Float16)r7; s6 = (_Float16)t2 - (_Float16)r8; t2 = (_Float16)t2 + (_Float16)r8; p1 = (_Float16)co2 * (_Float16)r1; p2 = (_Float16)si2 * (_Float16)s1; p3 = (_Float16)co2 * (_Float16)s1; p4 = (_Float16)si2 * (_Float16)r1; pSrc[2 * i2] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i2 + 1] = (_Float16)p3 - (_Float16)p4; p1 = (_Float16)co8 * (_Float16)r5; p2 = (_Float16)si8 * (_Float16)s5; p3 = (_Float16)co8 * (_Float16)s5; p4 = (_Float16)si8 * (_Float16)r5; pSrc[2 * i8] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i8 + 1] = (_Float16)p3 - (_Float16)p4; p1 = (_Float16)co6 * (_Float16)r6; p2 = (_Float16)si6 * (_Float16)s6; p3 = (_Float16)co6 * (_Float16)s6; p4 = (_Float16)si6 * (_Float16)r6; pSrc[2 * i6] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i6 + 1] = (_Float16)p3 - (_Float16)p4; p1 = (_Float16)co4 * (_Float16)t1; p2 = (_Float16)si4 * (_Float16)t2; p3 = (_Float16)co4 * (_Float16)t2; p4 = (_Float16)si4 * (_Float16)t1; pSrc[2 * i4] = (_Float16)p1 + (_Float16)p2; pSrc[2 * i4 + 1] = (_Float16)p3 - (_Float16)p4; i1 += n1; } while (i1 < fftLen); j++; } while (j < n2); twidCoefModifier <<= 3; } while (n2 > 7); } #endif /* #if defined(ARM_FLOAT16_SUPPORTED) */