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diff --git a/third_party/libwebrtc/modules/audio_processing/agc2/rnn_vad/vector_math.h b/third_party/libwebrtc/modules/audio_processing/agc2/rnn_vad/vector_math.h
new file mode 100644
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+++ b/third_party/libwebrtc/modules/audio_processing/agc2/rnn_vad/vector_math.h
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+/*
+ *  Copyright (c) 2020 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.
+ */
+
+#ifndef MODULES_AUDIO_PROCESSING_AGC2_RNN_VAD_VECTOR_MATH_H_
+#define MODULES_AUDIO_PROCESSING_AGC2_RNN_VAD_VECTOR_MATH_H_
+
+// Defines WEBRTC_ARCH_X86_FAMILY, used below.
+#include "rtc_base/system/arch.h"
+
+#if defined(WEBRTC_HAS_NEON)
+#include <arm_neon.h>
+#endif
+#if defined(WEBRTC_ARCH_X86_FAMILY)
+#include <emmintrin.h>
+#endif
+
+#include <numeric>
+
+#include "api/array_view.h"
+#include "modules/audio_processing/agc2/cpu_features.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/numerics/safe_conversions.h"
+#include "rtc_base/system/arch.h"
+
+namespace webrtc {
+namespace rnn_vad {
+
+// Provides optimizations for mathematical operations having vectors as
+// operand(s).
+class VectorMath {
+ public:
+  explicit VectorMath(AvailableCpuFeatures cpu_features)
+      : cpu_features_(cpu_features) {}
+
+  // Computes the dot product between two equally sized vectors.
+  float DotProduct(rtc::ArrayView<const float> x,
+                   rtc::ArrayView<const float> y) const {
+    RTC_DCHECK_EQ(x.size(), y.size());
+#if defined(WEBRTC_ARCH_X86_FAMILY)
+    if (cpu_features_.avx2) {
+      return DotProductAvx2(x, y);
+    } else if (cpu_features_.sse2) {
+      __m128 accumulator = _mm_setzero_ps();
+      constexpr int kBlockSizeLog2 = 2;
+      constexpr int kBlockSize = 1 << kBlockSizeLog2;
+      const int incomplete_block_index = (x.size() >> kBlockSizeLog2)
+                                         << kBlockSizeLog2;
+      for (int i = 0; i < incomplete_block_index; i += kBlockSize) {
+        RTC_DCHECK_LE(i + kBlockSize, x.size());
+        const __m128 x_i = _mm_loadu_ps(&x[i]);
+        const __m128 y_i = _mm_loadu_ps(&y[i]);
+        // Multiply-add.
+        const __m128 z_j = _mm_mul_ps(x_i, y_i);
+        accumulator = _mm_add_ps(accumulator, z_j);
+      }
+      // Reduce `accumulator` by addition.
+      __m128 high = _mm_movehl_ps(accumulator, accumulator);
+      accumulator = _mm_add_ps(accumulator, high);
+      high = _mm_shuffle_ps(accumulator, accumulator, 1);
+      accumulator = _mm_add_ps(accumulator, high);
+      float dot_product = _mm_cvtss_f32(accumulator);
+      // Add the result for the last block if incomplete.
+      for (int i = incomplete_block_index;
+           i < rtc::dchecked_cast<int>(x.size()); ++i) {
+        dot_product += x[i] * y[i];
+      }
+      return dot_product;
+    }
+#elif defined(WEBRTC_HAS_NEON) && defined(WEBRTC_ARCH_ARM64)
+    if (cpu_features_.neon) {
+      float32x4_t accumulator = vdupq_n_f32(0.f);
+      constexpr int kBlockSizeLog2 = 2;
+      constexpr int kBlockSize = 1 << kBlockSizeLog2;
+      const int incomplete_block_index = (x.size() >> kBlockSizeLog2)
+                                         << kBlockSizeLog2;
+      for (int i = 0; i < incomplete_block_index; i += kBlockSize) {
+        RTC_DCHECK_LE(i + kBlockSize, x.size());
+        const float32x4_t x_i = vld1q_f32(&x[i]);
+        const float32x4_t y_i = vld1q_f32(&y[i]);
+        accumulator = vfmaq_f32(accumulator, x_i, y_i);
+      }
+      // Reduce `accumulator` by addition.
+      const float32x2_t tmp =
+          vpadd_f32(vget_low_f32(accumulator), vget_high_f32(accumulator));
+      float dot_product = vget_lane_f32(vpadd_f32(tmp, vrev64_f32(tmp)), 0);
+      // Add the result for the last block if incomplete.
+      for (int i = incomplete_block_index;
+           i < rtc::dchecked_cast<int>(x.size()); ++i) {
+        dot_product += x[i] * y[i];
+      }
+      return dot_product;
+    }
+#endif
+    return std::inner_product(x.begin(), x.end(), y.begin(), 0.f);
+  }
+
+ private:
+  float DotProductAvx2(rtc::ArrayView<const float> x,
+                       rtc::ArrayView<const float> y) const;
+
+  const AvailableCpuFeatures cpu_features_;
+};
+
+}  // namespace rnn_vad
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_AGC2_RNN_VAD_VECTOR_MATH_H_