| /* |
| * Copyright (c) 2012 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/signal_processing/dot_product_with_scale.h" |
| |
| #include "webrtc/rtc_base/safe_conversions.h" |
| |
| int32_t WebRtcSpl_DotProductWithScale(const int16_t* vector1, |
| const int16_t* vector2, |
| size_t length, |
| int scaling) { |
| int64_t sum = 0; |
| size_t i = 0; |
| |
| /* Unroll the loop to improve performance. */ |
| for (i = 0; i + 3 < length; i += 4) { |
| sum += (vector1[i + 0] * vector2[i + 0]) >> scaling; |
| sum += (vector1[i + 1] * vector2[i + 1]) >> scaling; |
| sum += (vector1[i + 2] * vector2[i + 2]) >> scaling; |
| sum += (vector1[i + 3] * vector2[i + 3]) >> scaling; |
| } |
| for (; i < length; i++) { |
| sum += (vector1[i] * vector2[i]) >> scaling; |
| } |
| |
| return rtc::saturated_cast<int32_t>(sum); |
| } |