webrtc/modules/audio_processing/aec3/block_delay_buffer.cc
cschuldt a018e677f2 Optimize block_delay_buffer.
Reducing pointer following. This will allow the compiler to optimize more efficiently with the "-fno-strict-aliasing" flag.

Bug: None
Change-Id: Ic126bd2d53969a7e9d15e1c1081d5278e27a816c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/238664
Reviewed-by: Per Åhgren <peah@webrtc.org>
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Commit-Queue: Christian Schuldt <cschuldt@google.com>
Cr-Commit-Position: refs/heads/main@{#35414}
2021-11-24 12:20:28 +00:00

69 lines
2.3 KiB
C++

/*
* Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "modules/audio_processing/aec3/block_delay_buffer.h"
#include "api/array_view.h"
#include "rtc_base/checks.h"
namespace webrtc {
BlockDelayBuffer::BlockDelayBuffer(size_t num_channels,
size_t num_bands,
size_t frame_length,
size_t delay_samples)
: frame_length_(frame_length),
delay_(delay_samples),
buf_(num_channels,
std::vector<std::vector<float>>(num_bands,
std::vector<float>(delay_, 0.f))) {}
BlockDelayBuffer::~BlockDelayBuffer() = default;
void BlockDelayBuffer::DelaySignal(AudioBuffer* frame) {
RTC_DCHECK_EQ(buf_.size(), frame->num_channels());
if (delay_ == 0) {
return;
}
const size_t num_bands = buf_[0].size();
const size_t num_channels = buf_.size();
const size_t i_start = last_insert_;
size_t i = 0;
for (size_t ch = 0; ch < num_channels; ++ch) {
RTC_DCHECK_EQ(buf_[ch].size(), frame->num_bands());
RTC_DCHECK_EQ(buf_[ch].size(), num_bands);
rtc::ArrayView<float* const> frame_ch(frame->split_bands(ch), num_bands);
const size_t delay = delay_;
for (size_t band = 0; band < num_bands; ++band) {
RTC_DCHECK_EQ(delay_, buf_[ch][band].size());
i = i_start;
// Offloading these pointers and class variables to local variables allows
// the compiler to optimize the below loop when compiling with
// '-fno-strict-aliasing'.
float* buf_ch_band = buf_[ch][band].data();
float* frame_ch_band = frame_ch[band];
for (size_t k = 0, frame_length = frame_length_; k < frame_length; ++k) {
const float tmp = buf_ch_band[i];
buf_ch_band[i] = frame_ch_band[k];
frame_ch_band[k] = tmp;
i = i < delay - 1 ? i + 1 : 0;
}
}
}
last_insert_ = i;
}
} // namespace webrtc