1 files changed, 80 insertions, 0 deletions
diff --git a/chromium/third_party/webrtc/common_audio/fir_filter_sse.cc b/chromium/third_party/webrtc/common_audio/fir_filter_sse.cc
new file mode 100644
index 00000000000..7d873a735c5
--- /dev/null
+++ b/chromium/third_party/webrtc/common_audio/fir_filter_sse.cc
@@ -0,0 +1,80 @@
+/*
+ *  Copyright (c) 2014 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 "webrtc/common_audio/fir_filter_sse.h"
+
+#include <assert.h>
+#include <string.h>
+#include <xmmintrin.h>
+
+#include "webrtc/system_wrappers/interface/aligned_malloc.h"
+
+namespace webrtc {
+
+FIRFilterSSE2::FIRFilterSSE2(const float* coefficients,
+                             size_t coefficients_length,
+                             size_t max_input_length)
+    :  // Closest higher multiple of four.
+      coefficients_length_((coefficients_length + 3) & ~0x03),
+      state_length_(coefficients_length_ - 1),
+      coefficients_(static_cast<float*>(
+          AlignedMalloc(sizeof(float) * coefficients_length_, 16))),
+      state_(static_cast<float*>(
+          AlignedMalloc(sizeof(float) * (max_input_length + state_length_),
+                        16))) {
+  // Add zeros at the end of the coefficients.
+  size_t padding = coefficients_length_ - coefficients_length;
+  memset(coefficients_.get(), 0.f, padding * sizeof(coefficients_[0]));
+  // The coefficients are reversed to compensate for the order in which the
+  // input samples are acquired (most recent last).
+  for (size_t i = 0; i < coefficients_length; ++i) {
+    coefficients_[i + padding] = coefficients[coefficients_length - i - 1];
+  }
+  memset(state_.get(),
+         0.f,
+         (max_input_length + state_length_) * sizeof(state_[0]));
+}
+
+void FIRFilterSSE2::Filter(const float* in, size_t length, float* out) {
+  assert(length > 0);
+
+  memcpy(&state_[state_length_], in, length * sizeof(*in));
+
+  // Convolves the input signal |in| with the filter kernel |coefficients_|
+  // taking into account the previous state.
+  for (size_t i = 0; i < length; ++i) {
+    float* in_ptr = &state_[i];
+    float* coef_ptr = coefficients_.get();
+
+    __m128 m_sum = _mm_setzero_ps();
+    __m128 m_in;
+
+    // Depending on if the pointer is aligned with 16 bytes or not it is loaded
+    // differently.
+    if (reinterpret_cast<uintptr_t>(in_ptr) & 0x0F) {
+      for (size_t j = 0; j < coefficients_length_; j += 4) {
+        m_in = _mm_loadu_ps(in_ptr + j);
+        m_sum = _mm_add_ps(m_sum, _mm_mul_ps(m_in, _mm_load_ps(coef_ptr + j)));
+      }
+    } else {
+      for (size_t j = 0; j < coefficients_length_; j += 4) {
+        m_in = _mm_load_ps(in_ptr + j);
+        m_sum = _mm_add_ps(m_sum, _mm_mul_ps(m_in, _mm_load_ps(coef_ptr + j)));
+      }
+    }
+    m_sum = _mm_add_ps(_mm_movehl_ps(m_sum, m_sum), m_sum);
+    _mm_store_ss(out + i, _mm_add_ss(m_sum, _mm_shuffle_ps(m_sum, m_sum, 1)));
+  }
+
+  // Update current state.
+  memmove(state_.get(), &state_[length], state_length_ * sizeof(state_[0]));
+}
+
+}  // namespace webrtc