libwebp: update to 0.5.0

third_party/libwebp/dsp/lossless_enc_sse2.c

+// 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 variant of methods for lossless encoder
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "./dsp.h"
+
+#if defined(WEBP_USE_SSE2)
+#include <assert.h>
+#include <emmintrin.h>
+#include "./lossless.h"
+
+// For sign-extended multiplying constants, pre-shifted by 5:
+#define CST_5b(X)  (((int16_t)((uint16_t)X << 8)) >> 5)
+
+//------------------------------------------------------------------------------
+// Subtract-Green Transform
+
+static void SubtractGreenFromBlueAndRed(uint32_t* argb_data, int num_pixels) {
+  int i;
+  for (i = 0; i + 4 <= num_pixels; i += 4) {
+    const __m128i in = _mm_loadu_si128((__m128i*)&argb_data[i]); // argb
+    const __m128i A = _mm_srli_epi16(in, 8);     // 0 a 0 g
+    const __m128i B = _mm_shufflelo_epi16(A, _MM_SHUFFLE(2, 2, 0, 0));
+    const __m128i C = _mm_shufflehi_epi16(B, _MM_SHUFFLE(2, 2, 0, 0));  // 0g0g
+    const __m128i out = _mm_sub_epi8(in, C);
+    _mm_storeu_si128((__m128i*)&argb_data[i], out);
+  }
+  // fallthrough and finish off with plain-C
+  VP8LSubtractGreenFromBlueAndRed_C(argb_data + i, num_pixels - i);
+}
+
+//------------------------------------------------------------------------------
+// Color Transform
+
+static void TransformColor(const VP8LMultipliers* const m,
+                           uint32_t* argb_data, int num_pixels) {
+  const __m128i mults_rb = _mm_set_epi16(
+      CST_5b(m->green_to_red_), CST_5b(m->green_to_blue_),
+      CST_5b(m->green_to_red_), CST_5b(m->green_to_blue_),
+      CST_5b(m->green_to_red_), CST_5b(m->green_to_blue_),
+      CST_5b(m->green_to_red_), CST_5b(m->green_to_blue_));
+  const __m128i mults_b2 = _mm_set_epi16(
+      CST_5b(m->red_to_blue_), 0, CST_5b(m->red_to_blue_), 0,
+      CST_5b(m->red_to_blue_), 0, CST_5b(m->red_to_blue_), 0);
+  const __m128i mask_ag = _mm_set1_epi32(0xff00ff00);  // alpha-green masks
+  const __m128i mask_rb = _mm_set1_epi32(0x00ff00ff);  // red-blue masks
+  int i;
+  for (i = 0; i + 4 <= num_pixels; i += 4) {
+    const __m128i in = _mm_loadu_si128((__m128i*)&argb_data[i]); // argb
+    const __m128i A = _mm_and_si128(in, mask_ag);     // a   0   g   0
+    const __m128i B = _mm_shufflelo_epi16(A, _MM_SHUFFLE(2, 2, 0, 0));
+    const __m128i C = _mm_shufflehi_epi16(B, _MM_SHUFFLE(2, 2, 0, 0));  // g0g0
+    const __m128i D = _mm_mulhi_epi16(C, mults_rb);    // x dr  x db1
+    const __m128i E = _mm_slli_epi16(in, 8);           // r 0   b   0
+    const __m128i F = _mm_mulhi_epi16(E, mults_b2);    // x db2 0   0
+    const __m128i G = _mm_srli_epi32(F, 16);           // 0 0   x db2
+    const __m128i H = _mm_add_epi8(G, D);              // x dr  x  db
+    const __m128i I = _mm_and_si128(H, mask_rb);       // 0 dr  0  db
+    const __m128i out = _mm_sub_epi8(in, I);
+    _mm_storeu_si128((__m128i*)&argb_data[i], out);
+  }
+  // fallthrough and finish off with plain-C
+  VP8LTransformColor_C(m, argb_data + i, num_pixels - i);
+}
+
+//------------------------------------------------------------------------------
+#define SPAN 8
+static void CollectColorBlueTransforms(const uint32_t* argb, int stride,
+                                       int tile_width, int tile_height,
+                                       int green_to_blue, int red_to_blue,
+                                       int histo[]) {
+  const __m128i mults_r = _mm_set_epi16(
+      CST_5b(red_to_blue), 0, CST_5b(red_to_blue), 0,
+      CST_5b(red_to_blue), 0, CST_5b(red_to_blue), 0);
+  const __m128i mults_g = _mm_set_epi16(
+      0, CST_5b(green_to_blue), 0, CST_5b(green_to_blue),
+      0, CST_5b(green_to_blue), 0, CST_5b(green_to_blue));
+  const __m128i mask_g = _mm_set1_epi32(0x00ff00);  // green mask
+  const __m128i mask_b = _mm_set1_epi32(0x0000ff);  // blue mask
+  int y;
+  for (y = 0; y < tile_height; ++y) {
+    const uint32_t* const src = argb + y * stride;
+    int i, x;
+    for (x = 0; x + SPAN <= tile_width; x += SPAN) {
+      uint16_t values[SPAN];
+      const __m128i in0 = _mm_loadu_si128((__m128i*)&src[x +        0]);
+      const __m128i in1 = _mm_loadu_si128((__m128i*)&src[x + SPAN / 2]);
+      const __m128i A0 = _mm_slli_epi16(in0, 8);        // r 0  | b 0
+      const __m128i A1 = _mm_slli_epi16(in1, 8);
+      const __m128i B0 = _mm_and_si128(in0, mask_g);    // 0 0  | g 0
+      const __m128i B1 = _mm_and_si128(in1, mask_g);
+      const __m128i C0 = _mm_mulhi_epi16(A0, mults_r);  // x db | 0 0
+      const __m128i C1 = _mm_mulhi_epi16(A1, mults_r);
+      const __m128i D0 = _mm_mulhi_epi16(B0, mults_g);  // 0 0  | x db
+      const __m128i D1 = _mm_mulhi_epi16(B1, mults_g);
+      const __m128i E0 = _mm_sub_epi8(in0, D0);         // x x  | x b'
+      const __m128i E1 = _mm_sub_epi8(in1, D1);
+      const __m128i F0 = _mm_srli_epi32(C0, 16);        // 0 0  | x db
+      const __m128i F1 = _mm_srli_epi32(C1, 16);
+      const __m128i G0 = _mm_sub_epi8(E0, F0);          // 0 0  | x b'
+      const __m128i G1 = _mm_sub_epi8(E1, F1);
+      const __m128i H0 = _mm_and_si128(G0, mask_b);     // 0 0  | 0 b
+      const __m128i H1 = _mm_and_si128(G1, mask_b);
+      const __m128i I = _mm_packs_epi32(H0, H1);        // 0 b' | 0 b'
+      _mm_storeu_si128((__m128i*)values, I);
+      for (i = 0; i < SPAN; ++i) ++histo[values[i]];
+    }
+  }
+  {
+    const int left_over = tile_width & (SPAN - 1);
+    if (left_over > 0) {
+      VP8LCollectColorBlueTransforms_C(argb + tile_width - left_over, stride,
+                                       left_over, tile_height,
+                                       green_to_blue, red_to_blue, histo);
+    }
+  }
+}
+
+static void CollectColorRedTransforms(const uint32_t* argb, int stride,
+                                      int tile_width, int tile_height,
+                                      int green_to_red, int histo[]) {
+  const __m128i mults_g = _mm_set_epi16(
+      0, CST_5b(green_to_red), 0, CST_5b(green_to_red),
+      0, CST_5b(green_to_red), 0, CST_5b(green_to_red));
+  const __m128i mask_g = _mm_set1_epi32(0x00ff00);  // green mask
+  const __m128i mask = _mm_set1_epi32(0xff);
+
+  int y;
+  for (y = 0; y < tile_height; ++y) {
+    const uint32_t* const src = argb + y * stride;
+    int i, x;
+    for (x = 0; x + SPAN <= tile_width; x += SPAN) {
+      uint16_t values[SPAN];
+      const __m128i in0 = _mm_loadu_si128((__m128i*)&src[x +        0]);
+      const __m128i in1 = _mm_loadu_si128((__m128i*)&src[x + SPAN / 2]);
+      const __m128i A0 = _mm_and_si128(in0, mask_g);    // 0 0  | g 0
+      const __m128i A1 = _mm_and_si128(in1, mask_g);
+      const __m128i B0 = _mm_srli_epi32(in0, 16);       // 0 0  | x r
+      const __m128i B1 = _mm_srli_epi32(in1, 16);
+      const __m128i C0 = _mm_mulhi_epi16(A0, mults_g);  // 0 0  | x dr
+      const __m128i C1 = _mm_mulhi_epi16(A1, mults_g);
+      const __m128i E0 = _mm_sub_epi8(B0, C0);          // x x  | x r'
+      const __m128i E1 = _mm_sub_epi8(B1, C1);
+      const __m128i F0 = _mm_and_si128(E0, mask);       // 0 0  | 0 r'
+      const __m128i F1 = _mm_and_si128(E1, mask);
+      const __m128i I = _mm_packs_epi32(F0, F1);
+      _mm_storeu_si128((__m128i*)values, I);
+      for (i = 0; i < SPAN; ++i) ++histo[values[i]];
+    }
+  }
+  {
+    const int left_over = tile_width & (SPAN - 1);
+    if (left_over > 0) {
+      VP8LCollectColorRedTransforms_C(argb + tile_width - left_over, stride,
+                                      left_over, tile_height,
+                                      green_to_red, histo);
+    }
+  }
+}
+#undef SPAN
+
+//------------------------------------------------------------------------------
+
+#define LINE_SIZE 16    // 8 or 16
+static void AddVector(const uint32_t* a, const uint32_t* b, uint32_t* out,
+                      int size) {
+  int i;
+  assert(size % LINE_SIZE == 0);
+  for (i = 0; i < size; i += LINE_SIZE) {
+    const __m128i a0 = _mm_loadu_si128((const __m128i*)&a[i +  0]);
+    const __m128i a1 = _mm_loadu_si128((const __m128i*)&a[i +  4]);
+#if (LINE_SIZE == 16)
+    const __m128i a2 = _mm_loadu_si128((const __m128i*)&a[i +  8]);
+    const __m128i a3 = _mm_loadu_si128((const __m128i*)&a[i + 12]);
+#endif
+    const __m128i b0 = _mm_loadu_si128((const __m128i*)&b[i +  0]);
+    const __m128i b1 = _mm_loadu_si128((const __m128i*)&b[i +  4]);
+#if (LINE_SIZE == 16)
+    const __m128i b2 = _mm_loadu_si128((const __m128i*)&b[i +  8]);
+    const __m128i b3 = _mm_loadu_si128((const __m128i*)&b[i + 12]);
+#endif
+    _mm_storeu_si128((__m128i*)&out[i +  0], _mm_add_epi32(a0, b0));
+    _mm_storeu_si128((__m128i*)&out[i +  4], _mm_add_epi32(a1, b1));
+#if (LINE_SIZE == 16)
+    _mm_storeu_si128((__m128i*)&out[i +  8], _mm_add_epi32(a2, b2));
+    _mm_storeu_si128((__m128i*)&out[i + 12], _mm_add_epi32(a3, b3));
+#endif
+  }
+}
+
+static void AddVectorEq(const uint32_t* a, uint32_t* out, int size) {
+  int i;
+  assert(size % LINE_SIZE == 0);
+  for (i = 0; i < size; i += LINE_SIZE) {
+    const __m128i a0 = _mm_loadu_si128((const __m128i*)&a[i +  0]);
+    const __m128i a1 = _mm_loadu_si128((const __m128i*)&a[i +  4]);
+#if (LINE_SIZE == 16)
+    const __m128i a2 = _mm_loadu_si128((const __m128i*)&a[i +  8]);
+    const __m128i a3 = _mm_loadu_si128((const __m128i*)&a[i + 12]);
+#endif
+    const __m128i b0 = _mm_loadu_si128((const __m128i*)&out[i +  0]);
+    const __m128i b1 = _mm_loadu_si128((const __m128i*)&out[i +  4]);
+#if (LINE_SIZE == 16)
+    const __m128i b2 = _mm_loadu_si128((const __m128i*)&out[i +  8]);
+    const __m128i b3 = _mm_loadu_si128((const __m128i*)&out[i + 12]);
+#endif
+    _mm_storeu_si128((__m128i*)&out[i +  0], _mm_add_epi32(a0, b0));
+    _mm_storeu_si128((__m128i*)&out[i +  4], _mm_add_epi32(a1, b1));
+#if (LINE_SIZE == 16)
+    _mm_storeu_si128((__m128i*)&out[i +  8], _mm_add_epi32(a2, b2));
+    _mm_storeu_si128((__m128i*)&out[i + 12], _mm_add_epi32(a3, b3));
+#endif
+  }
+}
+#undef LINE_SIZE
+
+// Note we are adding uint32_t's as *signed* int32's (using _mm_add_epi32). But
+// that's ok since the histogram values are less than 1<<28 (max picture size).
+static void HistogramAdd(const VP8LHistogram* const a,
+                         const VP8LHistogram* const b,
+                         VP8LHistogram* const out) {
+  int i;
+  const int literal_size = VP8LHistogramNumCodes(a->palette_code_bits_);
+  assert(a->palette_code_bits_ == b->palette_code_bits_);
+  if (b != out) {
+    AddVector(a->literal_, b->literal_, out->literal_, NUM_LITERAL_CODES);
+    AddVector(a->red_, b->red_, out->red_, NUM_LITERAL_CODES);
+    AddVector(a->blue_, b->blue_, out->blue_, NUM_LITERAL_CODES);
+    AddVector(a->alpha_, b->alpha_, out->alpha_, NUM_LITERAL_CODES);
+  } else {
+    AddVectorEq(a->literal_, out->literal_, NUM_LITERAL_CODES);
+    AddVectorEq(a->red_, out->red_, NUM_LITERAL_CODES);
+    AddVectorEq(a->blue_, out->blue_, NUM_LITERAL_CODES);
+    AddVectorEq(a->alpha_, out->alpha_, NUM_LITERAL_CODES);
+  }
+  for (i = NUM_LITERAL_CODES; i < literal_size; ++i) {
+    out->literal_[i] = a->literal_[i] + b->literal_[i];
+  }
+  for (i = 0; i < NUM_DISTANCE_CODES; ++i) {
+    out->distance_[i] = a->distance_[i] + b->distance_[i];
+  }
+}
+
+//------------------------------------------------------------------------------
+// Entropy
+
+// Checks whether the X or Y contribution is worth computing and adding.
+// Used in loop unrolling.
+#define ANALYZE_X_OR_Y(x_or_y, j)                                   \
+  do {                                                              \
+    if (x_or_y[i + j] != 0) retval -= VP8LFastSLog2(x_or_y[i + j]); \
+  } while (0)
+
+// Checks whether the X + Y contribution is worth computing and adding.
+// Used in loop unrolling.
+#define ANALYZE_XY(j)                  \
+  do {                                 \
+    if (tmp[j] != 0) {                 \
+      retval -= VP8LFastSLog2(tmp[j]); \
+      ANALYZE_X_OR_Y(X, j);            \
+    }                                  \
+  } while (0)
+
+static float CombinedShannonEntropy(const int X[256], const int Y[256]) {
+  int i;
+  double retval = 0.;
+  int sumX, sumXY;
+  int32_t tmp[4];
+  __m128i zero = _mm_setzero_si128();
+  // Sums up X + Y, 4 ints at a time (and will merge it at the end for sumXY).
+  __m128i sumXY_128 = zero;
+  __m128i sumX_128 = zero;
+
+  for (i = 0; i < 256; i += 4) {
+    const __m128i x = _mm_loadu_si128((const __m128i*)(X + i));
+    const __m128i y = _mm_loadu_si128((const __m128i*)(Y + i));
+
+    // Check if any X is non-zero: this actually provides a speedup as X is
+    // usually sparse.
+    if (_mm_movemask_epi8(_mm_cmpeq_epi32(x, zero)) != 0xFFFF) {
+      const __m128i xy_128 = _mm_add_epi32(x, y);
+      sumXY_128 = _mm_add_epi32(sumXY_128, xy_128);
+
+      sumX_128 = _mm_add_epi32(sumX_128, x);
+
+      // Analyze the different X + Y.
+      _mm_storeu_si128((__m128i*)tmp, xy_128);
+
+      ANALYZE_XY(0);
+      ANALYZE_XY(1);
+      ANALYZE_XY(2);
+      ANALYZE_XY(3);
+    } else {
+      // X is fully 0, so only deal with Y.
+      sumXY_128 = _mm_add_epi32(sumXY_128, y);
+
+      ANALYZE_X_OR_Y(Y, 0);
+      ANALYZE_X_OR_Y(Y, 1);
+      ANALYZE_X_OR_Y(Y, 2);
+      ANALYZE_X_OR_Y(Y, 3);
+    }
+  }
+
+  // Sum up sumX_128 to get sumX.
+  _mm_storeu_si128((__m128i*)tmp, sumX_128);
+  sumX = tmp[3] + tmp[2] + tmp[1] + tmp[0];
+
+  // Sum up sumXY_128 to get sumXY.
+  _mm_storeu_si128((__m128i*)tmp, sumXY_128);
+  sumXY = tmp[3] + tmp[2] + tmp[1] + tmp[0];
+
+  retval += VP8LFastSLog2(sumX) + VP8LFastSLog2(sumXY);
+  return (float)retval;
+}
+#undef ANALYZE_X_OR_Y
+#undef ANALYZE_XY
+
+//------------------------------------------------------------------------------
+// Entry point
+
+extern void VP8LEncDspInitSSE2(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void VP8LEncDspInitSSE2(void) {
+  VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRed;
+  VP8LTransformColor = TransformColor;
+  VP8LCollectColorBlueTransforms = CollectColorBlueTransforms;
+  VP8LCollectColorRedTransforms = CollectColorRedTransforms;
+  VP8LHistogramAdd = HistogramAdd;
+  VP8LCombinedShannonEntropy = CombinedShannonEntropy;
+}
+
+#else  // !WEBP_USE_SSE2
+
+WEBP_DSP_INIT_STUB(VP8LEncDspInitSSE2)
+
+#endif  // WEBP_USE_SSE2