Use the upstream version of libwebp, v0.4.3.

third_party/libwebp/dsp/lossless_mips32.c

Index: third_party/libwebp/dsp/lossless_mips32.c
diff --git a/third_party/libwebp/dsp/lossless_mips32.c b/third_party/libwebp/dsp/lossless_mips32.c
new file mode 100644
index 0000000000000000000000000000000000000000..1308580790294f06d83194c158671a436262ea42
--- /dev/null
+++ b/third_party/libwebp/dsp/lossless_mips32.c
@@ -0,0 +1,416 @@
+// Copyright 2014 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.
+// -----------------------------------------------------------------------------
+//
+// MIPS version of lossless functions
+//
+// Author(s):  Djordje Pesut    (djordje.pesut@imgtec.com)
+//             Jovan Zelincevic (jovan.zelincevic@imgtec.com)
+
+#include "./dsp.h"
+#include "./lossless.h"
+
+#if defined(WEBP_USE_MIPS32)
+
+#include <assert.h>
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define APPROX_LOG_WITH_CORRECTION_MAX  65536
+#define APPROX_LOG_MAX                   4096
+#define LOG_2_RECIPROCAL 1.44269504088896338700465094007086
+
+static float FastSLog2Slow(uint32_t v) {
+  assert(v >= LOG_LOOKUP_IDX_MAX);
+  if (v < APPROX_LOG_WITH_CORRECTION_MAX) {
+    uint32_t log_cnt, y, correction;
+    const int c24 = 24;
+    const float v_f = (float)v;
+    uint32_t temp;
+
+    // Xf = 256 = 2^8
+    // log_cnt is index of leading one in upper 24 bits
+    __asm__ volatile(
+      "clz      %[log_cnt], %[v]                      \n\t"
+      "addiu    %[y],       $zero,        1           \n\t"
+      "subu     %[log_cnt], %[c24],       %[log_cnt]  \n\t"
+      "sllv     %[y],       %[y],         %[log_cnt]  \n\t"
+      "srlv     %[temp],    %[v],         %[log_cnt]  \n\t"
+      : [log_cnt]"=&r"(log_cnt), [y]"=&r"(y),
+        [temp]"=r"(temp)
+      : [c24]"r"(c24), [v]"r"(v)
+    );
+
+    // vf = (2^log_cnt) * Xf; where y = 2^log_cnt and Xf < 256
+    // Xf = floor(Xf) * (1 + (v % y) / v)
+    // log2(Xf) = log2(floor(Xf)) + log2(1 + (v % y) / v)
+    // The correction factor: log(1 + d) ~ d; for very small d values, so
+    // log2(1 + (v % y) / v) ~ LOG_2_RECIPROCAL * (v % y)/v
+    // LOG_2_RECIPROCAL ~ 23/16
+
+    // (v % y) = (v % 2^log_cnt) = v & (2^log_cnt - 1)
+    correction = (23 * (v & (y - 1))) >> 4;
+    return v_f * (kLog2Table[temp] + log_cnt) + correction;
+  } else {
+    return (float)(LOG_2_RECIPROCAL * v * log((double)v));
+  }
+}
+
+static float FastLog2Slow(uint32_t v) {
+  assert(v >= LOG_LOOKUP_IDX_MAX);
+  if (v < APPROX_LOG_WITH_CORRECTION_MAX) {
+    uint32_t log_cnt, y;
+    const int c24 = 24;
+    double log_2;
+    uint32_t temp;
+
+    __asm__ volatile(
+      "clz      %[log_cnt], %[v]                      \n\t"
+      "addiu    %[y],       $zero,        1           \n\t"
+      "subu     %[log_cnt], %[c24],       %[log_cnt]  \n\t"
+      "sllv     %[y],       %[y],         %[log_cnt]  \n\t"
+      "srlv     %[temp],    %[v],         %[log_cnt]  \n\t"
+      : [log_cnt]"=&r"(log_cnt), [y]"=&r"(y),
+        [temp]"=r"(temp)
+      : [c24]"r"(c24), [v]"r"(v)
+    );
+
+    log_2 = kLog2Table[temp] + log_cnt;
+    if (v >= APPROX_LOG_MAX) {
+      // Since the division is still expensive, add this correction factor only
+      // for large values of 'v'.
+
+      const uint32_t correction = (23 * (v & (y - 1))) >> 4;
+      log_2 += (double)correction / v;
+    }
+    return (float)log_2;
+  } else {
+    return (float)(LOG_2_RECIPROCAL * log((double)v));
+  }
+}
+
+// C version of this function:
+//   int i = 0;
+//   int64_t cost = 0;
+//   const uint32_t* pop = &population[4];
+//   const uint32_t* LoopEnd = &population[length];
+//   while (pop != LoopEnd) {
+//     ++i;
+//     cost += i * *pop;
+//     cost += i * *(pop + 1);
+//     pop += 2;
+//   }
+//   return (double)cost;
+static double ExtraCost(const uint32_t* const population, int length) {
+  int i, temp0, temp1;
+  const uint32_t* pop = &population[4];
+  const uint32_t* const LoopEnd = &population[length];
+
+  __asm__ volatile(
+    "mult   $zero,    $zero                  \n\t"
+    "xor    %[i],     %[i],       %[i]       \n\t"
+    "beq    %[pop],   %[LoopEnd], 2f         \n\t"
+  "1:                                        \n\t"
+    "lw     %[temp0], 0(%[pop])              \n\t"
+    "lw     %[temp1], 4(%[pop])              \n\t"
+    "addiu  %[i],     %[i],       1          \n\t"
+    "addiu  %[pop],   %[pop],     8          \n\t"
+    "madd   %[i],     %[temp0]               \n\t"
+    "madd   %[i],     %[temp1]               \n\t"
+    "bne    %[pop],   %[LoopEnd], 1b         \n\t"
+  "2:                                        \n\t"
+    "mfhi   %[temp0]                         \n\t"
+    "mflo   %[temp1]                         \n\t"
+    : [temp0]"=&r"(temp0), [temp1]"=&r"(temp1),
+      [i]"=&r"(i), [pop]"+r"(pop)
+    : [LoopEnd]"r"(LoopEnd)
+    : "memory", "hi", "lo"
+  );
+
+  return (double)((int64_t)temp0 << 32 | temp1);
+}
+
+// C version of this function:
+//   int i = 0;
+//   int64_t cost = 0;
+//   const uint32_t* pX = &X[4];
+//   const uint32_t* pY = &Y[4];
+//   const uint32_t* LoopEnd = &X[length];
+//   while (pX != LoopEnd) {
+//     const uint32_t xy0 = *pX + *pY;
+//     const uint32_t xy1 = *(pX + 1) + *(pY + 1);
+//     ++i;
+//     cost += i * xy0;
+//     cost += i * xy1;
+//     pX += 2;
+//     pY += 2;
+//   }
+//   return (double)cost;
+static double ExtraCostCombined(const uint32_t* const X,
+                                const uint32_t* const Y, int length) {
+  int i, temp0, temp1, temp2, temp3;
+  const uint32_t* pX = &X[4];
+  const uint32_t* pY = &Y[4];
+  const uint32_t* const LoopEnd = &X[length];
+
+  __asm__ volatile(
+    "mult   $zero,    $zero                  \n\t"
+    "xor    %[i],     %[i],       %[i]       \n\t"
+    "beq    %[pX],    %[LoopEnd], 2f         \n\t"
+  "1:                                        \n\t"
+    "lw     %[temp0], 0(%[pX])               \n\t"
+    "lw     %[temp1], 0(%[pY])               \n\t"
+    "lw     %[temp2], 4(%[pX])               \n\t"
+    "lw     %[temp3], 4(%[pY])               \n\t"
+    "addiu  %[i],     %[i],       1          \n\t"
+    "addu   %[temp0], %[temp0],   %[temp1]   \n\t"
+    "addu   %[temp2], %[temp2],   %[temp3]   \n\t"
+    "addiu  %[pX],    %[pX],      8          \n\t"
+    "addiu  %[pY],    %[pY],      8          \n\t"
+    "madd   %[i],     %[temp0]               \n\t"
+    "madd   %[i],     %[temp2]               \n\t"
+    "bne    %[pX],    %[LoopEnd], 1b         \n\t"
+  "2:                                        \n\t"
+    "mfhi   %[temp0]                         \n\t"
+    "mflo   %[temp1]                         \n\t"
+    : [temp0]"=&r"(temp0), [temp1]"=&r"(temp1),
+      [temp2]"=&r"(temp2), [temp3]"=&r"(temp3),
+      [i]"=&r"(i), [pX]"+r"(pX), [pY]"+r"(pY)
+    : [LoopEnd]"r"(LoopEnd)
+    : "memory", "hi", "lo"
+  );
+
+  return (double)((int64_t)temp0 << 32 | temp1);
+}
+
+#define HUFFMAN_COST_PASS                                 \
+  __asm__ volatile(                                       \
+    "sll   %[temp1],  %[temp0],    3           \n\t"      \
+    "addiu %[temp3],  %[streak],   -3          \n\t"      \
+    "addu  %[temp2],  %[pstreaks], %[temp1]    \n\t"      \
+    "blez  %[temp3],  1f                       \n\t"      \
+    "srl   %[temp1],  %[temp1],    1           \n\t"      \
+    "addu  %[temp3],  %[pcnts],    %[temp1]    \n\t"      \
+    "lw    %[temp0],  4(%[temp2])              \n\t"      \
+    "lw    %[temp1],  0(%[temp3])              \n\t"      \
+    "addu  %[temp0],  %[temp0],    %[streak]   \n\t"      \
+    "addiu %[temp1],  %[temp1],    1           \n\t"      \
+    "sw    %[temp0],  4(%[temp2])              \n\t"      \
+    "sw    %[temp1],  0(%[temp3])              \n\t"      \
+    "b     2f                                  \n\t"      \
+  "1:                                          \n\t"      \
+    "lw    %[temp0],  0(%[temp2])              \n\t"      \
+    "addu  %[temp0],  %[temp0],    %[streak]   \n\t"      \
+    "sw    %[temp0],  0(%[temp2])              \n\t"      \
+  "2:                                          \n\t"      \
+    : [temp1]"=&r"(temp1), [temp2]"=&r"(temp2),           \
+      [temp3]"=&r"(temp3), [temp0]"+r"(temp0)             \
+    : [pstreaks]"r"(pstreaks), [pcnts]"r"(pcnts),         \
+      [streak]"r"(streak)                                 \
+    : "memory"                                            \
+  );
+
+// Returns the various RLE counts
+static VP8LStreaks HuffmanCostCount(const uint32_t* population, int length) {
+  int i;
+  int streak = 0;
+  VP8LStreaks stats;
+  int* const pstreaks = &stats.streaks[0][0];
+  int* const pcnts = &stats.counts[0];
+  int temp0, temp1, temp2, temp3;
+  memset(&stats, 0, sizeof(stats));
+  for (i = 0; i < length - 1; ++i) {
+    ++streak;
+    if (population[i] == population[i + 1]) {
+      continue;
+    }
+    temp0 = (population[i] != 0);
+    HUFFMAN_COST_PASS
+    streak = 0;
+  }
+  ++streak;
+  temp0 = (population[i] != 0);
+  HUFFMAN_COST_PASS
+
+  return stats;
+}
+
+static VP8LStreaks HuffmanCostCombinedCount(const uint32_t* X,
+                                            const uint32_t* Y, int length) {
+  int i;
+  int streak = 0;
+  VP8LStreaks stats;
+  int* const pstreaks = &stats.streaks[0][0];
+  int* const pcnts = &stats.counts[0];
+  int temp0, temp1, temp2, temp3;
+  memset(&stats, 0, sizeof(stats));
+  for (i = 0; i < length - 1; ++i) {
+    const uint32_t xy = X[i] + Y[i];
+    const uint32_t xy_next = X[i + 1] + Y[i + 1];
+    ++streak;
+    if (xy == xy_next) {
+      continue;
+    }
+    temp0 = (xy != 0);
+    HUFFMAN_COST_PASS
+    streak = 0;
+  }
+  {
+    const uint32_t xy = X[i] + Y[i];
+    ++streak;
+    temp0 = (xy != 0);
+    HUFFMAN_COST_PASS
+  }
+
+  return stats;
+}
+
+#define ASM_START                                       \
+  __asm__ volatile(                                     \
+    ".set   push                            \n\t"       \
+    ".set   at                              \n\t"       \
+    ".set   macro                           \n\t"       \
+  "1:                                       \n\t"
+
+// P2 = P0 + P1
+// A..D - offsets
+// E - temp variable to tell macro
+//     if pointer should be incremented
+// literal_ and successive histograms could be unaligned
+// so we must use ulw and usw
+#define ADD_TO_OUT(A, B, C, D, E, P0, P1, P2)           \
+    "ulw    %[temp0], "#A"(%["#P0"])        \n\t"       \
+    "ulw    %[temp1], "#B"(%["#P0"])        \n\t"       \
+    "ulw    %[temp2], "#C"(%["#P0"])        \n\t"       \
+    "ulw    %[temp3], "#D"(%["#P0"])        \n\t"       \
+    "ulw    %[temp4], "#A"(%["#P1"])        \n\t"       \
+    "ulw    %[temp5], "#B"(%["#P1"])        \n\t"       \
+    "ulw    %[temp6], "#C"(%["#P1"])        \n\t"       \
+    "ulw    %[temp7], "#D"(%["#P1"])        \n\t"       \
+    "addu   %[temp4], %[temp4],   %[temp0]  \n\t"       \
+    "addu   %[temp5], %[temp5],   %[temp1]  \n\t"       \
+    "addu   %[temp6], %[temp6],   %[temp2]  \n\t"       \
+    "addu   %[temp7], %[temp7],   %[temp3]  \n\t"       \
+    "addiu  %["#P0"],  %["#P0"],  16        \n\t"       \
+  ".if "#E" == 1                            \n\t"       \
+    "addiu  %["#P1"],  %["#P1"],  16        \n\t"       \
+  ".endif                                   \n\t"       \
+    "usw    %[temp4], "#A"(%["#P2"])        \n\t"       \
+    "usw    %[temp5], "#B"(%["#P2"])        \n\t"       \
+    "usw    %[temp6], "#C"(%["#P2"])        \n\t"       \
+    "usw    %[temp7], "#D"(%["#P2"])        \n\t"       \
+    "addiu  %["#P2"], %["#P2"],   16        \n\t"       \
+    "bne    %["#P0"], %[LoopEnd], 1b        \n\t"       \
+    ".set   pop                             \n\t"       \
+
+#define ASM_END_COMMON_0                                \
+    : [temp0]"=&r"(temp0), [temp1]"=&r"(temp1),         \
+      [temp2]"=&r"(temp2), [temp3]"=&r"(temp3),         \
+      [temp4]"=&r"(temp4), [temp5]"=&r"(temp5),         \
+      [temp6]"=&r"(temp6), [temp7]"=&r"(temp7),         \
+      [pa]"+r"(pa), [pout]"+r"(pout)
+
+#define ASM_END_COMMON_1                                \
+    : [LoopEnd]"r"(LoopEnd)                             \
+    : "memory", "at"                                    \
+  );
+
+#define ASM_END_0                                       \
+    ASM_END_COMMON_0                                    \
+      , [pb]"+r"(pb)                                    \
+    ASM_END_COMMON_1
+
+#define ASM_END_1                                       \
+    ASM_END_COMMON_0                                    \
+    ASM_END_COMMON_1
+
+#define ADD_VECTOR(A, B, OUT, SIZE, EXTRA_SIZE)  do {   \
+  const uint32_t* pa = (const uint32_t*)(A);            \
+  const uint32_t* pb = (const uint32_t*)(B);            \
+  uint32_t* pout = (uint32_t*)(OUT);                    \
+  const uint32_t* const LoopEnd = pa + (SIZE);          \
+  assert((SIZE) % 4 == 0);                              \
+  ASM_START                                             \
+  ADD_TO_OUT(0, 4, 8, 12, 1, pa, pb, pout)              \
+  ASM_END_0                                             \
+  if ((EXTRA_SIZE) > 0) {                               \
+    const int last = (EXTRA_SIZE);                      \
+    int i;                                              \
+    for (i = 0; i < last; ++i) pout[i] = pa[i] + pb[i]; \
+  }                                                     \
+} while (0)
+
+#define ADD_VECTOR_EQ(A, OUT, SIZE, EXTRA_SIZE)  do {   \
+  const uint32_t* pa = (const uint32_t*)(A);            \
+  uint32_t* pout = (uint32_t*)(OUT);                    \
+  const uint32_t* const LoopEnd = pa + (SIZE);          \
+  assert((SIZE) % 4 == 0);                              \
+  ASM_START                                             \
+  ADD_TO_OUT(0, 4, 8, 12, 0, pa, pout, pout)            \
+  ASM_END_1                                             \
+  if ((EXTRA_SIZE) > 0) {                               \
+    const int last = (EXTRA_SIZE);                      \
+    int i;                                              \
+    for (i = 0; i < last; ++i) pout[i] += pa[i];        \
+  }                                                     \
+} while (0)
+
+static void HistogramAdd(const VP8LHistogram* const a,
+                         const VP8LHistogram* const b,
+                         VP8LHistogram* const out) {
+  uint32_t temp0, temp1, temp2, temp3, temp4, temp5, temp6, temp7;
+  const int extra_cache_size = VP8LHistogramNumCodes(a->palette_code_bits_)
+                             - (NUM_LITERAL_CODES + NUM_LENGTH_CODES);
+  assert(a->palette_code_bits_ == b->palette_code_bits_);
+
+  if (b != out) {
+    ADD_VECTOR(a->literal_, b->literal_, out->literal_,
+               NUM_LITERAL_CODES + NUM_LENGTH_CODES, extra_cache_size);
+    ADD_VECTOR(a->distance_, b->distance_, out->distance_,
+               NUM_DISTANCE_CODES, 0);
+    ADD_VECTOR(a->red_, b->red_, out->red_, NUM_LITERAL_CODES, 0);
+    ADD_VECTOR(a->blue_, b->blue_, out->blue_, NUM_LITERAL_CODES, 0);
+    ADD_VECTOR(a->alpha_, b->alpha_, out->alpha_, NUM_LITERAL_CODES, 0);
+  } else {
+    ADD_VECTOR_EQ(a->literal_, out->literal_,
+                  NUM_LITERAL_CODES + NUM_LENGTH_CODES, extra_cache_size);
+    ADD_VECTOR_EQ(a->distance_, out->distance_, NUM_DISTANCE_CODES, 0);
+    ADD_VECTOR_EQ(a->red_, out->red_, NUM_LITERAL_CODES, 0);
+    ADD_VECTOR_EQ(a->blue_, out->blue_, NUM_LITERAL_CODES, 0);
+    ADD_VECTOR_EQ(a->alpha_, out->alpha_, NUM_LITERAL_CODES, 0);
+  }
+}
+
+#undef ADD_VECTOR_EQ
+#undef ADD_VECTOR
+#undef ASM_END_1
+#undef ASM_END_0
+#undef ASM_END_COMMON_1
+#undef ASM_END_COMMON_0
+#undef ADD_TO_OUT
+#undef ASM_START
+
+#endif  // WEBP_USE_MIPS32
+
+//------------------------------------------------------------------------------
+// Entry point
+
+extern void VP8LDspInitMIPS32(void);
+
+void VP8LDspInitMIPS32(void) {
+#if defined(WEBP_USE_MIPS32)
+  VP8LFastSLog2Slow = FastSLog2Slow;
+  VP8LFastLog2Slow = FastLog2Slow;
+  VP8LExtraCost = ExtraCost;
+  VP8LExtraCostCombined = ExtraCostCombined;
+  VP8LHuffmanCostCount = HuffmanCostCount;
+  VP8LHuffmanCostCombinedCount = HuffmanCostCombinedCount;
+  VP8LHistogramAdd = HistogramAdd;
+#endif  // WEBP_USE_MIPS32
+}