Optimize CascadedBiQuadFilter.
Unloading states and coefficients to local variables avoids excessive memory access when building with "-fno-strict-aliasing".
Bug: None
Change-Id: I90bf81ae794c21e9e41500c5040387cf67ebdd38
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/240320
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Commit-Queue: Christian Schuldt <cschuldt@google.com>
Cr-Commit-Position: refs/heads/main@{#35518}
diff --git a/modules/audio_processing/utility/cascaded_biquad_filter.cc b/modules/audio_processing/utility/cascaded_biquad_filter.cc
index 08b9464..0d236ce 100644
--- a/modules/audio_processing/utility/cascaded_biquad_filter.cc
+++ b/modules/audio_processing/utility/cascaded_biquad_filter.cc
@@ -99,19 +99,28 @@
rtc::ArrayView<float> y,
CascadedBiQuadFilter::BiQuad* biquad) {
RTC_DCHECK_EQ(x.size(), y.size());
- const auto* c_b = biquad->coefficients.b;
- const auto* c_a = biquad->coefficients.a;
- auto* m_x = biquad->x;
- auto* m_y = biquad->y;
+ const float c_a_0 = biquad->coefficients.a[0];
+ const float c_a_1 = biquad->coefficients.a[1];
+ const float c_b_0 = biquad->coefficients.b[0];
+ const float c_b_1 = biquad->coefficients.b[1];
+ const float c_b_2 = biquad->coefficients.b[2];
+ float m_x_0 = biquad->x[0];
+ float m_x_1 = biquad->x[1];
+ float m_y_0 = biquad->y[0];
+ float m_y_1 = biquad->y[1];
for (size_t k = 0; k < x.size(); ++k) {
const float tmp = x[k];
- y[k] = c_b[0] * tmp + c_b[1] * m_x[0] + c_b[2] * m_x[1] - c_a[0] * m_y[0] -
- c_a[1] * m_y[1];
- m_x[1] = m_x[0];
- m_x[0] = tmp;
- m_y[1] = m_y[0];
- m_y[0] = y[k];
+ y[k] = c_b_0 * tmp + c_b_1 * m_x_0 + c_b_2 * m_x_1 - c_a_0 * m_y_0 -
+ c_a_1 * m_y_1;
+ m_x_1 = m_x_0;
+ m_x_0 = tmp;
+ m_y_1 = m_y_0;
+ m_y_0 = y[k];
}
+ biquad->x[0] = m_x_0;
+ biquad->x[1] = m_x_1;
+ biquad->y[0] = m_y_0;
+ biquad->y[1] = m_y_1;
}
} // namespace webrtc
