diff options
Diffstat (limited to 'chromium/media/base/simd/vector_math_sse.cc')
-rw-r--r-- | chromium/media/base/simd/vector_math_sse.cc | 118 |
1 files changed, 0 insertions, 118 deletions
diff --git a/chromium/media/base/simd/vector_math_sse.cc b/chromium/media/base/simd/vector_math_sse.cc deleted file mode 100644 index c2121225cd6..00000000000 --- a/chromium/media/base/simd/vector_math_sse.cc +++ /dev/null @@ -1,118 +0,0 @@ -// Copyright 2013 The Chromium Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "media/base/vector_math_testing.h" - -#include <algorithm> - -#include <xmmintrin.h> // NOLINT - -namespace media { -namespace vector_math { - -void FMUL_SSE(const float src[], float scale, int len, float dest[]) { - const int rem = len % 4; - const int last_index = len - rem; - __m128 m_scale = _mm_set_ps1(scale); - for (int i = 0; i < last_index; i += 4) - _mm_store_ps(dest + i, _mm_mul_ps(_mm_load_ps(src + i), m_scale)); - - // Handle any remaining values that wouldn't fit in an SSE pass. - for (int i = last_index; i < len; ++i) - dest[i] = src[i] * scale; -} - -void FMAC_SSE(const float src[], float scale, int len, float dest[]) { - const int rem = len % 4; - const int last_index = len - rem; - __m128 m_scale = _mm_set_ps1(scale); - for (int i = 0; i < last_index; i += 4) { - _mm_store_ps(dest + i, _mm_add_ps(_mm_load_ps(dest + i), - _mm_mul_ps(_mm_load_ps(src + i), m_scale))); - } - - // Handle any remaining values that wouldn't fit in an SSE pass. - for (int i = last_index; i < len; ++i) - dest[i] += src[i] * scale; -} - -// Convenience macro to extract float 0 through 3 from the vector |a|. This is -// needed because compilers other than clang don't support access via -// operator[](). -#define EXTRACT_FLOAT(a, i) \ - (i == 0 ? \ - _mm_cvtss_f32(a) : \ - _mm_cvtss_f32(_mm_shuffle_ps(a, a, i))) - -std::pair<float, float> EWMAAndMaxPower_SSE( - float initial_value, const float src[], int len, float smoothing_factor) { - // When the recurrence is unrolled, we see that we can split it into 4 - // separate lanes of evaluation: - // - // y[n] = a(S[n]^2) + (1-a)(y[n-1]) - // = a(S[n]^2) + (1-a)^1(aS[n-1]^2) + (1-a)^2(aS[n-2]^2) + ... - // = z[n] + (1-a)^1(z[n-1]) + (1-a)^2(z[n-2]) + (1-a)^3(z[n-3]) - // - // where z[n] = a(S[n]^2) + (1-a)^4(z[n-4]) + (1-a)^8(z[n-8]) + ... - // - // Thus, the strategy here is to compute z[n], z[n-1], z[n-2], and z[n-3] in - // each of the 4 lanes, and then combine them to give y[n]. - - const int rem = len % 4; - const int last_index = len - rem; - - const __m128 smoothing_factor_x4 = _mm_set_ps1(smoothing_factor); - const float weight_prev = 1.0f - smoothing_factor; - const __m128 weight_prev_x4 = _mm_set_ps1(weight_prev); - const __m128 weight_prev_squared_x4 = - _mm_mul_ps(weight_prev_x4, weight_prev_x4); - const __m128 weight_prev_4th_x4 = - _mm_mul_ps(weight_prev_squared_x4, weight_prev_squared_x4); - - // Compute z[n], z[n-1], z[n-2], and z[n-3] in parallel in lanes 3, 2, 1 and - // 0, respectively. - __m128 max_x4 = _mm_setzero_ps(); - __m128 ewma_x4 = _mm_setr_ps(0.0f, 0.0f, 0.0f, initial_value); - int i; - for (i = 0; i < last_index; i += 4) { - ewma_x4 = _mm_mul_ps(ewma_x4, weight_prev_4th_x4); - const __m128 sample_x4 = _mm_load_ps(src + i); - const __m128 sample_squared_x4 = _mm_mul_ps(sample_x4, sample_x4); - max_x4 = _mm_max_ps(max_x4, sample_squared_x4); - // Note: The compiler optimizes this to a single multiply-and-accumulate - // instruction: - ewma_x4 = _mm_add_ps(ewma_x4, - _mm_mul_ps(sample_squared_x4, smoothing_factor_x4)); - } - - // y[n] = z[n] + (1-a)^1(z[n-1]) + (1-a)^2(z[n-2]) + (1-a)^3(z[n-3]) - float ewma = EXTRACT_FLOAT(ewma_x4, 3); - ewma_x4 = _mm_mul_ps(ewma_x4, weight_prev_x4); - ewma += EXTRACT_FLOAT(ewma_x4, 2); - ewma_x4 = _mm_mul_ps(ewma_x4, weight_prev_x4); - ewma += EXTRACT_FLOAT(ewma_x4, 1); - ewma_x4 = _mm_mul_ss(ewma_x4, weight_prev_x4); - ewma += EXTRACT_FLOAT(ewma_x4, 0); - - // Fold the maximums together to get the overall maximum. - max_x4 = _mm_max_ps(max_x4, - _mm_shuffle_ps(max_x4, max_x4, _MM_SHUFFLE(3, 3, 1, 1))); - max_x4 = _mm_max_ss(max_x4, _mm_shuffle_ps(max_x4, max_x4, 2)); - - std::pair<float, float> result(ewma, EXTRACT_FLOAT(max_x4, 0)); - - // Handle remaining values at the end of |src|. - for (; i < len; ++i) { - result.first *= weight_prev; - const float sample = src[i]; - const float sample_squared = sample * sample; - result.first += sample_squared * smoothing_factor; - result.second = std::max(result.second, sample_squared); - } - - return result; -} - -} // namespace vector_math -} // namespace media |