libwebp: update to 0.5.0

This commit imports libwebp 0.5.0, including AUTHORS, COPYING, ChangeLog,
NEWS, PATENTS, README and src directories. In src, only includes header
and source files.

The patches required to build it in Qt will follow in separate
commit(s).

Change-Id: I96b4961ba63c75cc7fbab158c36a0f403f254c14
Reviewed-by: aavit <eirik.aavitsland@theqtcompany.com>

1 files changed, 374 insertions, 0 deletions

diff --git a/src/3rdparty/libwebp/src/dsp/rescaler_sse2.c b/src/3rdparty/libwebp/src/dsp/rescaler_sse2.c
new file mode 100644
index 0000000..5ea4ddb
--- /dev/null
+++ b/src/3rdparty/libwebp/src/dsp/rescaler_sse2.c
@@ -0,0 +1,374 @@
+// 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 Rescaling functions
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "./dsp.h"
+
+#if defined(WEBP_USE_SSE2)
+#include <emmintrin.h>
+
+#include <assert.h>
+#include "../utils/rescaler.h"
+
+//------------------------------------------------------------------------------
+// Implementations of critical functions ImportRow / ExportRow
+
+#define ROUNDER (WEBP_RESCALER_ONE >> 1)
+#define MULT_FIX(x, y) (((uint64_t)(x) * (y) + ROUNDER) >> WEBP_RESCALER_RFIX)
+
+// input: 8 bytes ABCDEFGH -> output: A0E0B0F0C0G0D0H0
+static void LoadTwoPixels(const uint8_t* const src, __m128i* out) {
+  const __m128i zero = _mm_setzero_si128();
+  const __m128i A = _mm_loadl_epi64((const __m128i*)(src));  // ABCDEFGH
+  const __m128i B = _mm_unpacklo_epi8(A, zero);              // A0B0C0D0E0F0G0H0
+  const __m128i C = _mm_srli_si128(B, 8);                    // E0F0G0H0
+  *out = _mm_unpacklo_epi16(B, C);
+}
+
+// input: 8 bytes ABCDEFGH -> output: A0B0C0D0E0F0G0H0
+static void LoadHeightPixels(const uint8_t* const src, __m128i* out) {
+  const __m128i zero = _mm_setzero_si128();
+  const __m128i A = _mm_loadl_epi64((const __m128i*)(src));  // ABCDEFGH
+  *out = _mm_unpacklo_epi8(A, zero);
+}
+
+static void RescalerImportRowExpandSSE2(WebPRescaler* const wrk,
+                                        const uint8_t* src) {
+  rescaler_t* frow = wrk->frow;
+  const rescaler_t* const frow_end = frow + wrk->dst_width * wrk->num_channels;
+  const int x_add = wrk->x_add;
+  int accum = x_add;
+  __m128i cur_pixels;
+
+  assert(!WebPRescalerInputDone(wrk));
+  assert(wrk->x_expand);
+  if (wrk->num_channels == 4) {
+    if (wrk->src_width < 2) {
+      WebPRescalerImportRowExpandC(wrk, src);
+      return;
+    }
+    LoadTwoPixels(src, &cur_pixels);
+    src += 4;
+    while (1) {
+      const __m128i mult = _mm_set1_epi32(((x_add - accum) << 16) | accum);
+      const __m128i out = _mm_madd_epi16(cur_pixels, mult);
+      _mm_storeu_si128((__m128i*)frow, out);
+      frow += 4;
+      if (frow >= frow_end) break;
+      accum -= wrk->x_sub;
+      if (accum < 0) {
+        LoadTwoPixels(src, &cur_pixels);
+        src += 4;
+        accum += x_add;
+      }
+    }
+  } else {
+    int left;
+    const uint8_t* const src_limit = src + wrk->src_width - 8;
+    if (wrk->src_width < 8) {
+      WebPRescalerImportRowExpandC(wrk, src);
+      return;
+    }
+    LoadHeightPixels(src, &cur_pixels);
+    src += 7;
+    left = 7;
+    while (1) {
+      const __m128i mult = _mm_cvtsi32_si128(((x_add - accum) << 16) | accum);
+      const __m128i out = _mm_madd_epi16(cur_pixels, mult);
+      assert(sizeof(*frow) == sizeof(uint32_t));
+      WebPUint32ToMem((uint8_t*)frow, _mm_cvtsi128_si32(out));
+      frow += 1;
+      if (frow >= frow_end) break;
+      accum -= wrk->x_sub;
+      if (accum < 0) {
+        if (--left) {
+          cur_pixels = _mm_srli_si128(cur_pixels, 2);
+        } else if (src <= src_limit) {
+          LoadHeightPixels(src, &cur_pixels);
+          src += 7;
+          left = 7;
+        } else {   // tail
+          cur_pixels = _mm_srli_si128(cur_pixels, 2);
+          cur_pixels = _mm_insert_epi16(cur_pixels, src[1], 1);
+          src += 1;
+          left = 1;
+        }
+        accum += x_add;
+      }
+    }
+  }
+  assert(accum == 0);
+}
+
+static void RescalerImportRowShrinkSSE2(WebPRescaler* const wrk,
+                                        const uint8_t* src) {
+  const int x_sub = wrk->x_sub;
+  int accum = 0;
+  const __m128i zero = _mm_setzero_si128();
+  const __m128i mult0 = _mm_set1_epi16(x_sub);
+  const __m128i mult1 = _mm_set1_epi32(wrk->fx_scale);
+  const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
+  __m128i sum = zero;
+  rescaler_t* frow = wrk->frow;
+  const rescaler_t* const frow_end = wrk->frow + 4 * wrk->dst_width;
+
+  if (wrk->num_channels != 4 || wrk->x_add > (x_sub << 7)) {
+    WebPRescalerImportRowShrinkC(wrk, src);
+    return;
+  }
+  assert(!WebPRescalerInputDone(wrk));
+  assert(!wrk->x_expand);
+
+  for (; frow < frow_end; frow += 4) {
+    __m128i base = zero;
+    accum += wrk->x_add;
+    while (accum > 0) {
+      const __m128i A = _mm_cvtsi32_si128(WebPMemToUint32(src));
+      src += 4;
+      base = _mm_unpacklo_epi8(A, zero);
+      // To avoid overflow, we need: base * x_add / x_sub < 32768
+      // => x_add < x_sub << 7. That's a 1/128 reduction ratio limit.
+      sum = _mm_add_epi16(sum, base);
+      accum -= x_sub;
+    }
+    {    // Emit next horizontal pixel.
+      const __m128i mult = _mm_set1_epi16(-accum);
+      const __m128i frac0 = _mm_mullo_epi16(base, mult);  // 16b x 16b -> 32b
+      const __m128i frac1 = _mm_mulhi_epu16(base, mult);
+      const __m128i frac = _mm_unpacklo_epi16(frac0, frac1);  // frac is 32b
+      const __m128i A0 = _mm_mullo_epi16(sum, mult0);
+      const __m128i A1 = _mm_mulhi_epu16(sum, mult0);
+      const __m128i B0 = _mm_unpacklo_epi16(A0, A1);      // sum * x_sub
+      const __m128i frow_out = _mm_sub_epi32(B0, frac);   // sum * x_sub - frac
+      const __m128i D0 = _mm_srli_epi64(frac, 32);
+      const __m128i D1 = _mm_mul_epu32(frac, mult1);      // 32b x 16b -> 64b
+      const __m128i D2 = _mm_mul_epu32(D0, mult1);
+      const __m128i E1 = _mm_add_epi64(D1, rounder);
+      const __m128i E2 = _mm_add_epi64(D2, rounder);
+      const __m128i F1 = _mm_shuffle_epi32(E1, 1 | (3 << 2));
+      const __m128i F2 = _mm_shuffle_epi32(E2, 1 | (3 << 2));
+      const __m128i G = _mm_unpacklo_epi32(F1, F2);
+      sum = _mm_packs_epi32(G, zero);
+      _mm_storeu_si128((__m128i*)frow, frow_out);
+    }
+  }
+  assert(accum == 0);
+}
+
+//------------------------------------------------------------------------------
+// Row export
+
+// load *src as epi64, multiply by mult and store result in [out0 ... out3]
+static WEBP_INLINE void LoadDispatchAndMult(const rescaler_t* const src,
+                                            const __m128i* const mult,
+                                            __m128i* const out0,
+                                            __m128i* const out1,
+                                            __m128i* const out2,
+                                            __m128i* const out3) {
+  const __m128i A0 = _mm_loadu_si128((const __m128i*)(src + 0));
+  const __m128i A1 = _mm_loadu_si128((const __m128i*)(src + 4));
+  const __m128i A2 = _mm_srli_epi64(A0, 32);
+  const __m128i A3 = _mm_srli_epi64(A1, 32);
+  if (mult != NULL) {
+    *out0 = _mm_mul_epu32(A0, *mult);
+    *out1 = _mm_mul_epu32(A1, *mult);
+    *out2 = _mm_mul_epu32(A2, *mult);
+    *out3 = _mm_mul_epu32(A3, *mult);
+  } else {
+    *out0 = A0;
+    *out1 = A1;
+    *out2 = A2;
+    *out3 = A3;
+  }
+}
+
+static WEBP_INLINE void ProcessRow(const __m128i* const A0,
+                                   const __m128i* const A1,
+                                   const __m128i* const A2,
+                                   const __m128i* const A3,
+                                   const __m128i* const mult,
+                                   uint8_t* const dst) {
+  const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
+  const __m128i mask = _mm_set_epi32(0xffffffffu, 0, 0xffffffffu, 0);
+  const __m128i B0 = _mm_mul_epu32(*A0, *mult);
+  const __m128i B1 = _mm_mul_epu32(*A1, *mult);
+  const __m128i B2 = _mm_mul_epu32(*A2, *mult);
+  const __m128i B3 = _mm_mul_epu32(*A3, *mult);
+  const __m128i C0 = _mm_add_epi64(B0, rounder);
+  const __m128i C1 = _mm_add_epi64(B1, rounder);
+  const __m128i C2 = _mm_add_epi64(B2, rounder);
+  const __m128i C3 = _mm_add_epi64(B3, rounder);
+  const __m128i D0 = _mm_srli_epi64(C0, WEBP_RESCALER_RFIX);
+  const __m128i D1 = _mm_srli_epi64(C1, WEBP_RESCALER_RFIX);
+#if (WEBP_RESCALER_FIX < 32)
+  const __m128i D2 =
+      _mm_and_si128(_mm_slli_epi64(C2, 32 - WEBP_RESCALER_RFIX), mask);
+  const __m128i D3 =
+      _mm_and_si128(_mm_slli_epi64(C3, 32 - WEBP_RESCALER_RFIX), mask);
+#else
+  const __m128i D2 = _mm_and_si128(C2, mask);
+  const __m128i D3 = _mm_and_si128(C3, mask);
+#endif
+  const __m128i E0 = _mm_or_si128(D0, D2);
+  const __m128i E1 = _mm_or_si128(D1, D3);
+  const __m128i F = _mm_packs_epi32(E0, E1);
+  const __m128i G = _mm_packus_epi16(F, F);
+  _mm_storel_epi64((__m128i*)dst, G);
+}
+
+static void RescalerExportRowExpandSSE2(WebPRescaler* const wrk) {
+  int x_out;
+  uint8_t* const dst = wrk->dst;
+  rescaler_t* const irow = wrk->irow;
+  const int x_out_max = wrk->dst_width * wrk->num_channels;
+  const rescaler_t* const frow = wrk->frow;
+  const __m128i mult = _mm_set_epi32(0, wrk->fy_scale, 0, wrk->fy_scale);
+
+  assert(!WebPRescalerOutputDone(wrk));
+  assert(wrk->y_accum <= 0 && wrk->y_sub + wrk->y_accum >= 0);
+  assert(wrk->y_expand);
+  if (wrk->y_accum == 0) {
+    for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
+      __m128i A0, A1, A2, A3;
+      LoadDispatchAndMult(frow + x_out, NULL, &A0, &A1, &A2, &A3);
+      ProcessRow(&A0, &A1, &A2, &A3, &mult, dst + x_out);
+    }
+    for (; x_out < x_out_max; ++x_out) {
+      const uint32_t J = frow[x_out];
+      const int v = (int)MULT_FIX(J, wrk->fy_scale);
+      assert(v >= 0 && v <= 255);
+      dst[x_out] = v;
+    }
+  } else {
+    const uint32_t B = WEBP_RESCALER_FRAC(-wrk->y_accum, wrk->y_sub);
+    const uint32_t A = (uint32_t)(WEBP_RESCALER_ONE - B);
+    const __m128i mA = _mm_set_epi32(0, A, 0, A);
+    const __m128i mB = _mm_set_epi32(0, B, 0, B);
+    const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
+    for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
+      __m128i A0, A1, A2, A3, B0, B1, B2, B3;
+      LoadDispatchAndMult(frow + x_out, &mA, &A0, &A1, &A2, &A3);
+      LoadDispatchAndMult(irow + x_out, &mB, &B0, &B1, &B2, &B3);
+      {
+        const __m128i C0 = _mm_add_epi64(A0, B0);
+        const __m128i C1 = _mm_add_epi64(A1, B1);
+        const __m128i C2 = _mm_add_epi64(A2, B2);
+        const __m128i C3 = _mm_add_epi64(A3, B3);
+        const __m128i D0 = _mm_add_epi64(C0, rounder);
+        const __m128i D1 = _mm_add_epi64(C1, rounder);
+        const __m128i D2 = _mm_add_epi64(C2, rounder);
+        const __m128i D3 = _mm_add_epi64(C3, rounder);
+        const __m128i E0 = _mm_srli_epi64(D0, WEBP_RESCALER_RFIX);
+        const __m128i E1 = _mm_srli_epi64(D1, WEBP_RESCALER_RFIX);
+        const __m128i E2 = _mm_srli_epi64(D2, WEBP_RESCALER_RFIX);
+        const __m128i E3 = _mm_srli_epi64(D3, WEBP_RESCALER_RFIX);
+        ProcessRow(&E0, &E1, &E2, &E3, &mult, dst + x_out);
+      }
+    }
+    for (; x_out < x_out_max; ++x_out) {
+      const uint64_t I = (uint64_t)A * frow[x_out]
+                       + (uint64_t)B * irow[x_out];
+      const uint32_t J = (uint32_t)((I + ROUNDER) >> WEBP_RESCALER_RFIX);
+      const int v = (int)MULT_FIX(J, wrk->fy_scale);
+      assert(v >= 0 && v <= 255);
+      dst[x_out] = v;
+    }
+  }
+}
+
+static void RescalerExportRowShrinkSSE2(WebPRescaler* const wrk) {
+  int x_out;
+  uint8_t* const dst = wrk->dst;
+  rescaler_t* const irow = wrk->irow;
+  const int x_out_max = wrk->dst_width * wrk->num_channels;
+  const rescaler_t* const frow = wrk->frow;
+  const uint32_t yscale = wrk->fy_scale * (-wrk->y_accum);
+  assert(!WebPRescalerOutputDone(wrk));
+  assert(wrk->y_accum <= 0);
+  assert(!wrk->y_expand);
+  if (yscale) {
+    const int scale_xy = wrk->fxy_scale;
+    const __m128i mult_xy = _mm_set_epi32(0, scale_xy, 0, scale_xy);
+    const __m128i mult_y = _mm_set_epi32(0, yscale, 0, yscale);
+    const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
+    for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
+      __m128i A0, A1, A2, A3, B0, B1, B2, B3;
+      LoadDispatchAndMult(irow + x_out, NULL, &A0, &A1, &A2, &A3);
+      LoadDispatchAndMult(frow + x_out, &mult_y, &B0, &B1, &B2, &B3);
+      {
+        const __m128i C0 = _mm_add_epi64(B0, rounder);
+        const __m128i C1 = _mm_add_epi64(B1, rounder);
+        const __m128i C2 = _mm_add_epi64(B2, rounder);
+        const __m128i C3 = _mm_add_epi64(B3, rounder);
+        const __m128i D0 = _mm_srli_epi64(C0, WEBP_RESCALER_RFIX);   // = frac
+        const __m128i D1 = _mm_srli_epi64(C1, WEBP_RESCALER_RFIX);
+        const __m128i D2 = _mm_srli_epi64(C2, WEBP_RESCALER_RFIX);
+        const __m128i D3 = _mm_srli_epi64(C3, WEBP_RESCALER_RFIX);
+        const __m128i E0 = _mm_sub_epi64(A0, D0);   // irow[x] - frac
+        const __m128i E1 = _mm_sub_epi64(A1, D1);
+        const __m128i E2 = _mm_sub_epi64(A2, D2);
+        const __m128i E3 = _mm_sub_epi64(A3, D3);
+        const __m128i F2 = _mm_slli_epi64(D2, 32);
+        const __m128i F3 = _mm_slli_epi64(D3, 32);
+        const __m128i G0 = _mm_or_si128(D0, F2);
+        const __m128i G1 = _mm_or_si128(D1, F3);
+        _mm_storeu_si128((__m128i*)(irow + x_out + 0), G0);
+        _mm_storeu_si128((__m128i*)(irow + x_out + 4), G1);
+        ProcessRow(&E0, &E1, &E2, &E3, &mult_xy, dst + x_out);
+      }
+    }
+    for (; x_out < x_out_max; ++x_out) {
+      const uint32_t frac = (int)MULT_FIX(frow[x_out], yscale);
+      const int v = (int)MULT_FIX(irow[x_out] - frac, wrk->fxy_scale);
+      assert(v >= 0 && v <= 255);
+      dst[x_out] = v;
+      irow[x_out] = frac;   // new fractional start
+    }
+  } else {
+    const uint32_t scale = wrk->fxy_scale;
+    const __m128i mult = _mm_set_epi32(0, scale, 0, scale);
+    const __m128i zero = _mm_setzero_si128();
+    for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
+      __m128i A0, A1, A2, A3;
+      LoadDispatchAndMult(irow + x_out, NULL, &A0, &A1, &A2, &A3);
+      _mm_storeu_si128((__m128i*)(irow + x_out + 0), zero);
+      _mm_storeu_si128((__m128i*)(irow + x_out + 4), zero);
+      ProcessRow(&A0, &A1, &A2, &A3, &mult, dst + x_out);
+    }
+    for (; x_out < x_out_max; ++x_out) {
+      const int v = (int)MULT_FIX(irow[x_out], scale);
+      assert(v >= 0 && v <= 255);
+      dst[x_out] = v;
+      irow[x_out] = 0;
+    }
+  }
+}
+
+#undef MULT_FIX
+#undef ROUNDER
+
+//------------------------------------------------------------------------------
+
+extern void WebPRescalerDspInitSSE2(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void WebPRescalerDspInitSSE2(void) {
+  WebPRescalerImportRowExpand = RescalerImportRowExpandSSE2;
+  WebPRescalerImportRowShrink = RescalerImportRowShrinkSSE2;
+  WebPRescalerExportRowExpand = RescalerExportRowExpandSSE2;
+  WebPRescalerExportRowShrink = RescalerExportRowShrinkSSE2;
+}
+
+#else  // !WEBP_USE_SSE2
+
+WEBP_DSP_INIT_STUB(WebPRescalerDspInitSSE2)
+
+#endif  // WEBP_USE_SSE2