summaryrefslogtreecommitdiffstats
path: root/media/libwebp/src/dsp/cost_sse2.c
diff options
context:
space:
mode:
Diffstat (limited to 'media/libwebp/src/dsp/cost_sse2.c')
-rw-r--r--media/libwebp/src/dsp/cost_sse2.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/media/libwebp/src/dsp/cost_sse2.c b/media/libwebp/src/dsp/cost_sse2.c
new file mode 100644
index 0000000000..487a079921
--- /dev/null
+++ b/media/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