// 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.

// -----------------------------------------------------------------------------

//

// SSE4.1 variant of methods for lossless encoder

//

// Author: Skal (pascal.massimino@gmail.com)

#include "src/dsp/dsp.h"

#if defined(WEBP_USE_SSE41)

#include <assert.h>

#include <smmintrin.h>

#include "src/dsp/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_SSE41(uint32_t* argb_data,

int num_pixels) {

int i;

const __m128i kCstShuffle = _mm_set_epi8(-1, 13, -1, 13, -1, 9, -1, 9,

-1, 5, -1, 5, -1, 1, -1, 1);

for (i = 0; i + 4 <= num_pixels; i += 4) {

const __m128i in = _mm_loadu_si128((__m128i*)&argb_data[i]);

const __m128i in_0g0g = _mm_shuffle_epi8(in, kCstShuffle);

const __m128i out = _mm_sub_epi8(in, in_0g0g);

_mm_storeu_si128((__m128i*)&argb_data[i], out);

}

// fallthrough and finish off with plain-C

if (i != num_pixels) {

VP8LSubtractGreenFromBlueAndRed_C(argb_data + i, num_pixels - i);

}

}

//------------------------------------------------------------------------------

// Color Transform

#define SPAN 8

static void CollectColorBlueTransforms_SSE41(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_set1_epi16(CST_5b(red_to_blue));

const __m128i mults_g = _mm_set1_epi16(CST_5b(green_to_blue));

const __m128i mask_g = _mm_set1_epi16((short)0xff00); // green mask

const __m128i mask_gb = _mm_set1_epi32(0xffff); // green/blue mask

const __m128i mask_b = _mm_set1_epi16(0x00ff); // blue mask

const __m128i shuffler_lo = _mm_setr_epi8(-1, 2, -1, 6, -1, 10, -1, 14, -1,

-1, -1, -1, -1, -1, -1, -1);

const __m128i shuffler_hi = _mm_setr_epi8(-1, -1, -1, -1, -1, -1, -1, -1, -1,

2, -1, 6, -1, 10, -1, 14);

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 r0 = _mm_shuffle_epi8(in0, shuffler_lo);

const __m128i r1 = _mm_shuffle_epi8(in1, shuffler_hi);

const __m128i r = _mm_or_si128(r0, r1); // r 0

const __m128i gb0 = _mm_and_si128(in0, mask_gb);

const __m128i gb1 = _mm_and_si128(in1, mask_gb);

const __m128i gb = _mm_packus_epi32(gb0, gb1); // g b

const __m128i g = _mm_and_si128(gb, mask_g); // g 0

const __m128i A = _mm_mulhi_epi16(r, mults_r); // x dbr

const __m128i B = _mm_mulhi_epi16(g, mults_g); // x dbg

const __m128i C = _mm_sub_epi8(gb, B); // x b'

const __m128i D = _mm_sub_epi8(C, A); // x b''

const __m128i E = _mm_and_si128(D, mask_b); // 0 b''

_mm_storeu_si128((__m128i*)values, E);

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_SSE41(const uint32_t* argb, int stride,

int tile_width, int tile_height,

int green_to_red, int histo[]) {

const __m128i mults_g = _mm_set1_epi16(CST_5b(green_to_red));

const __m128i mask_g = _mm_set1_epi32(0x00ff00); // green mask

const __m128i mask = _mm_set1_epi16(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 g0 = _mm_and_si128(in0, mask_g); // 0 0 | g 0

const __m128i g1 = _mm_and_si128(in1, mask_g);

const __m128i g = _mm_packus_epi32(g0, g1); // g 0

const __m128i A0 = _mm_srli_epi32(in0, 16); // 0 0 | x r

const __m128i A1 = _mm_srli_epi32(in1, 16);

const __m128i A = _mm_packus_epi32(A0, A1); // x r

const __m128i B = _mm_mulhi_epi16(g, mults_g); // x dr

const __m128i C = _mm_sub_epi8(A, B); // x r'

const __m128i D = _mm_and_si128(C, mask); // 0 r'

_mm_storeu_si128((__m128i*)values, D);

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);

}

}

}

//------------------------------------------------------------------------------

// Entry point

extern void VP8LEncDspInitSSE41(void);

WEBP_TSAN_IGNORE_FUNCTION void VP8LEncDspInitSSE41(void) {

VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRed_SSE41;

VP8LCollectColorBlueTransforms = CollectColorBlueTransforms_SSE41;

VP8LCollectColorRedTransforms = CollectColorRedTransforms_SSE41;

}

#else // !WEBP_USE_SSE41

WEBP_DSP_INIT_STUB(VP8LEncDspInitSSE41)

#endif // WEBP_USE_SSE41