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Diffstat (limited to 'thirdparty/libwebp/src/dsp/cost_sse2.c')
-rw-r--r-- | thirdparty/libwebp/src/dsp/cost_sse2.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/thirdparty/libwebp/src/dsp/cost_sse2.c b/thirdparty/libwebp/src/dsp/cost_sse2.c new file mode 100644 index 0000000000..487a079921 --- /dev/null +++ b/thirdparty/libwebp/src/dsp/cost_sse2.c @@ -0,0 +1,119 @@ +// Copyright 2015 Google Inc. All Rights Reserved. +// +// Use of this source code is governed by a BSD-style license +// that can be found in the COPYING 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. +// ----------------------------------------------------------------------------- +// +// SSE2 version of cost functions +// +// Author: Skal (pascal.massimino@gmail.com) + +#include "src/dsp/dsp.h" + +#if defined(WEBP_USE_SSE2) +#include <emmintrin.h> + +#include "src/enc/cost_enc.h" +#include "src/enc/vp8i_enc.h" +#include "src/utils/utils.h" + +//------------------------------------------------------------------------------ + +static void SetResidualCoeffs_SSE2(const int16_t* const coeffs, + VP8Residual* const res) { + const __m128i c0 = _mm_loadu_si128((const __m128i*)(coeffs + 0)); + const __m128i c1 = _mm_loadu_si128((const __m128i*)(coeffs + 8)); + // Use SSE2 to compare 16 values with a single instruction. + const __m128i zero = _mm_setzero_si128(); + const __m128i m0 = _mm_packs_epi16(c0, c1); + const __m128i m1 = _mm_cmpeq_epi8(m0, zero); + // Get the comparison results as a bitmask into 16bits. Negate the mask to get + // the position of entries that are not equal to zero. We don't need to mask + // out least significant bits according to res->first, since coeffs[0] is 0 + // if res->first > 0. + const uint32_t mask = 0x0000ffffu ^ (uint32_t)_mm_movemask_epi8(m1); + // The position of the most significant non-zero bit indicates the position of + // the last non-zero value. + assert(res->first == 0 || coeffs[0] == 0); + res->last = mask ? BitsLog2Floor(mask) : -1; + res->coeffs = coeffs; +} + +static int GetResidualCost_SSE2(int ctx0, const VP8Residual* const res) { + uint8_t levels[16], ctxs[16]; + uint16_t abs_levels[16]; + int n = res->first; + // should be prob[VP8EncBands[n]], but it's equivalent for n=0 or 1 + const int p0 = res->prob[n][ctx0][0]; + CostArrayPtr const costs = res->costs; + const uint16_t* t = costs[n][ctx0]; + // bit_cost(1, p0) is already incorporated in t[] tables, but only if ctx != 0 + // (as required by the syntax). For ctx0 == 0, we need to add it here or it'll + // be missing during the loop. + int cost = (ctx0 == 0) ? VP8BitCost(1, p0) : 0; + + if (res->last < 0) { + return VP8BitCost(0, p0); + } + + { // precompute clamped levels and contexts, packed to 8b. + const __m128i zero = _mm_setzero_si128(); + const __m128i kCst2 = _mm_set1_epi8(2); + const __m128i kCst67 = _mm_set1_epi8(MAX_VARIABLE_LEVEL); + const __m128i c0 = _mm_loadu_si128((const __m128i*)&res->coeffs[0]); + const __m128i c1 = _mm_loadu_si128((const __m128i*)&res->coeffs[8]); + const __m128i D0 = _mm_sub_epi16(zero, c0); + const __m128i D1 = _mm_sub_epi16(zero, c1); + const __m128i E0 = _mm_max_epi16(c0, D0); // abs(v), 16b + const __m128i E1 = _mm_max_epi16(c1, D1); + const __m128i F = _mm_packs_epi16(E0, E1); + const __m128i G = _mm_min_epu8(F, kCst2); // context = 0,1,2 + const __m128i H = _mm_min_epu8(F, kCst67); // clamp_level in [0..67] + + _mm_storeu_si128((__m128i*)&ctxs[0], G); + _mm_storeu_si128((__m128i*)&levels[0], H); + + _mm_storeu_si128((__m128i*)&abs_levels[0], E0); + _mm_storeu_si128((__m128i*)&abs_levels[8], E1); + } + for (; n < res->last; ++n) { + const int ctx = ctxs[n]; + const int level = levels[n]; + const int flevel = abs_levels[n]; // full level + cost += VP8LevelFixedCosts[flevel] + t[level]; // simplified VP8LevelCost() + t = costs[n + 1][ctx]; + } + // Last coefficient is always non-zero + { + const int level = levels[n]; + const int flevel = abs_levels[n]; + assert(flevel != 0); + cost += VP8LevelFixedCosts[flevel] + t[level]; + if (n < 15) { + const int b = VP8EncBands[n + 1]; + const int ctx = ctxs[n]; + const int last_p0 = res->prob[b][ctx][0]; + cost += VP8BitCost(0, last_p0); + } + } + return cost; +} + +//------------------------------------------------------------------------------ +// Entry point + +extern void VP8EncDspCostInitSSE2(void); + +WEBP_TSAN_IGNORE_FUNCTION void VP8EncDspCostInitSSE2(void) { + VP8SetResidualCoeffs = SetResidualCoeffs_SSE2; + VP8GetResidualCost = GetResidualCost_SSE2; +} + +#else // !WEBP_USE_SSE2 + +WEBP_DSP_INIT_STUB(VP8EncDspCostInitSSE2) + +#endif // WEBP_USE_SSE2 |