1 /*
2  *  Copyright (c) 2020 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include "modules/audio_processing/aec3/fft_data.h"
12 
13 #include <immintrin.h>
14 
15 #include "api/array_view.h"
16 
17 namespace webrtc {
18 
19 // Computes the power spectrum of the data.
SpectrumAVX2(rtc::ArrayView<float> power_spectrum) const20 void FftData::SpectrumAVX2(rtc::ArrayView<float> power_spectrum) const {
21   RTC_DCHECK_EQ(kFftLengthBy2Plus1, power_spectrum.size());
22   for (size_t k = 0; k < kFftLengthBy2; k += 8) {
23     __m256 r = _mm256_loadu_ps(&re[k]);
24     __m256 i = _mm256_loadu_ps(&im[k]);
25     __m256 ii = _mm256_mul_ps(i, i);
26     ii = _mm256_fmadd_ps(r, r, ii);
27     _mm256_storeu_ps(&power_spectrum[k], ii);
28   }
29   power_spectrum[kFftLengthBy2] = re[kFftLengthBy2] * re[kFftLengthBy2] +
30                                   im[kFftLengthBy2] * im[kFftLengthBy2];
31 }
32 
33 }  // namespace webrtc
34