// 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
//------------------------------------------------------------------------------
static int VectorMismatch(const uint32_t* const array1,
const uint32_t* const array2, int length) {
int match_len;
if (length >= 12) {
__m128i A0 = _mm_loadu_si128((const __m128i*)&array1[0]);
__m128i A1 = _mm_loadu_si128((const __m128i*)&array2[0]);
match_len = 0;
do {
// Loop unrolling and early load both provide a speedup of 10% for the
// current function. Also, max_limit can be MAX_LENGTH=4096 at most.
const __m128i cmpA = _mm_cmpeq_epi32(A0, A1);
const __m128i B0 =
_mm_loadu_si128((const __m128i*)&array1[match_len + 4]);
const __m128i B1 =
_mm_loadu_si128((const __m128i*)&array2[match_len + 4]);
if (_mm_movemask_epi8(cmpA) != 0xffff) break;
match_len += 4;
{
const __m128i cmpB = _mm_cmpeq_epi32(B0, B1);
A0 = _mm_loadu_si128((const __m128i*)&array1[match_len + 4]);
A1 = _mm_loadu_si128((const __m128i*)&array2[match_len + 4]);
if (_mm_movemask_epi8(cmpB) != 0xffff) break;
match_len += 4;
}
} while (match_len + 12 < length);
} else {
match_len = 0;
// Unroll the potential first two loops.
if (length >= 4 &&
_mm_movemask_epi8(_mm_cmpeq_epi32(
_mm_loadu_si128((const __m128i*)&array1[0]),
_mm_loadu_si128((const __m128i*)&array2[0]))) == 0xffff) {
match_len = 4;
if (length >= 8 &&
_mm_movemask_epi8(_mm_cmpeq_epi32(
_mm_loadu_si128((const __m128i*)&array1[4]),
_mm_loadu_si128((const __m128i*)&array2[4]))) == 0xffff)
match_len = 8;
}
}
while (match_len < length && array1[match_len] == array2[match_len]) {
++match_len;
}
return match_len;
}
//------------------------------------------------------------------------------
// 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;
VP8LVectorMismatch = VectorMismatch;
}
#else // !WEBP_USE_SSE2
WEBP_DSP_INIT_STUB(VP8LEncDspInitSSE2)
#endif // WEBP_USE_SSE2