blob: c017f7e4b3d1496f950e00f738dc30588226ecf9 [file] [log] [blame]
/*
* Copyright 2012 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <emmintrin.h>
#include "SkBitmapProcState_opts_SSE2.h"
#include "SkBlitRow_opts_SSE2.h"
#include "SkColorPriv.h"
#include "SkColor_opts_SSE2.h"
#include "SkDither.h"
#include "SkUtils.h"
/* SSE2 version of S32_Blend_BlitRow32()
* portable version is in core/SkBlitRow_D32.cpp
*/
void S32_Blend_BlitRow32_SSE2(SkPMColor* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha) {
SkASSERT(alpha <= 255);
if (count <= 0) {
return;
}
uint32_t src_scale = SkAlpha255To256(alpha);
uint32_t dst_scale = 256 - src_scale;
if (count >= 4) {
SkASSERT(((size_t)dst & 0x03) == 0);
while (((size_t)dst & 0x0F) != 0) {
*dst = SkAlphaMulQ(*src, src_scale) + SkAlphaMulQ(*dst, dst_scale);
src++;
dst++;
count--;
}
const __m128i *s = reinterpret_cast<const __m128i*>(src);
__m128i *d = reinterpret_cast<__m128i*>(dst);
while (count >= 4) {
// Load 4 pixels each of src and dest.
__m128i src_pixel = _mm_loadu_si128(s);
__m128i dst_pixel = _mm_load_si128(d);
src_pixel = SkAlphaMulQ_SSE2(src_pixel, src_scale);
dst_pixel = SkAlphaMulQ_SSE2(dst_pixel, dst_scale);
// Add result
__m128i result = _mm_add_epi8(src_pixel, dst_pixel);
_mm_store_si128(d, result);
s++;
d++;
count -= 4;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<SkPMColor*>(d);
}
while (count > 0) {
*dst = SkAlphaMulQ(*src, src_scale) + SkAlphaMulQ(*dst, dst_scale);
src++;
dst++;
count--;
}
}
void S32A_Opaque_BlitRow32_SSE2(SkPMColor* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha) {
SkASSERT(alpha == 255);
if (count <= 0) {
return;
}
#ifdef SK_USE_ACCURATE_BLENDING
if (count >= 4) {
SkASSERT(((size_t)dst & 0x03) == 0);
while (((size_t)dst & 0x0F) != 0) {
*dst = SkPMSrcOver(*src, *dst);
src++;
dst++;
count--;
}
const __m128i *s = reinterpret_cast<const __m128i*>(src);
__m128i *d = reinterpret_cast<__m128i*>(dst);
__m128i rb_mask = _mm_set1_epi32(0x00FF00FF);
__m128i c_128 = _mm_set1_epi16(128); // 8 copies of 128 (16-bit)
__m128i c_255 = _mm_set1_epi16(255); // 8 copies of 255 (16-bit)
while (count >= 4) {
// Load 4 pixels
__m128i src_pixel = _mm_loadu_si128(s);
__m128i dst_pixel = _mm_load_si128(d);
__m128i dst_rb = _mm_and_si128(rb_mask, dst_pixel);
__m128i dst_ag = _mm_srli_epi16(dst_pixel, 8);
// Shift alphas down to lower 8 bits of each quad.
__m128i alpha = _mm_srli_epi32(src_pixel, 24);
// Copy alpha to upper 3rd byte of each quad
alpha = _mm_or_si128(alpha, _mm_slli_epi32(alpha, 16));
// Subtract alphas from 255, to get 0..255
alpha = _mm_sub_epi16(c_255, alpha);
// Multiply by red and blue by src alpha.
dst_rb = _mm_mullo_epi16(dst_rb, alpha);
// Multiply by alpha and green by src alpha.
dst_ag = _mm_mullo_epi16(dst_ag, alpha);
// dst_rb_low = (dst_rb >> 8)
__m128i dst_rb_low = _mm_srli_epi16(dst_rb, 8);
__m128i dst_ag_low = _mm_srli_epi16(dst_ag, 8);
// dst_rb = (dst_rb + dst_rb_low + 128) >> 8
dst_rb = _mm_add_epi16(dst_rb, dst_rb_low);
dst_rb = _mm_add_epi16(dst_rb, c_128);
dst_rb = _mm_srli_epi16(dst_rb, 8);
// dst_ag = (dst_ag + dst_ag_low + 128) & ag_mask
dst_ag = _mm_add_epi16(dst_ag, dst_ag_low);
dst_ag = _mm_add_epi16(dst_ag, c_128);
dst_ag = _mm_andnot_si128(rb_mask, dst_ag);
// Combine back into RGBA.
dst_pixel = _mm_or_si128(dst_rb, dst_ag);
// Add result
__m128i result = _mm_add_epi8(src_pixel, dst_pixel);
_mm_store_si128(d, result);
s++;
d++;
count -= 4;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<SkPMColor*>(d);
}
while (count > 0) {
*dst = SkPMSrcOver(*src, *dst);
src++;
dst++;
count--;
}
#else
int count16 = count / 16;
__m128i* dst4 = (__m128i*)dst;
const __m128i* src4 = (const __m128i*)src;
for (int i = 0; i < count16 * 4; i += 4) {
// Load 16 source pixels.
__m128i s0 = _mm_loadu_si128(src4+i+0),
s1 = _mm_loadu_si128(src4+i+1),
s2 = _mm_loadu_si128(src4+i+2),
s3 = _mm_loadu_si128(src4+i+3);
const __m128i alphaMask = _mm_set1_epi32(0xFF << SK_A32_SHIFT);
const __m128i ORed = _mm_or_si128(s3, _mm_or_si128(s2, _mm_or_si128(s1, s0)));
__m128i cmp = _mm_cmpeq_epi8(_mm_and_si128(ORed, alphaMask), _mm_setzero_si128());
if (0xffff == _mm_movemask_epi8(cmp)) {
// All 16 source pixels are fully transparent. There's nothing to do!
continue;
}
const __m128i ANDed = _mm_and_si128(s3, _mm_and_si128(s2, _mm_and_si128(s1, s0)));
cmp = _mm_cmpeq_epi8(_mm_and_si128(ANDed, alphaMask), alphaMask);
if (0xffff == _mm_movemask_epi8(cmp)) {
// All 16 source pixels are fully opaque. There's no need to read dst or blend it.
_mm_storeu_si128(dst4+i+0, s0);
_mm_storeu_si128(dst4+i+1, s1);
_mm_storeu_si128(dst4+i+2, s2);
_mm_storeu_si128(dst4+i+3, s3);
continue;
}
// The general slow case: do the blend for all 16 pixels.
_mm_storeu_si128(dst4+i+0, SkPMSrcOver_SSE2(s0, _mm_loadu_si128(dst4+i+0)));
_mm_storeu_si128(dst4+i+1, SkPMSrcOver_SSE2(s1, _mm_loadu_si128(dst4+i+1)));
_mm_storeu_si128(dst4+i+2, SkPMSrcOver_SSE2(s2, _mm_loadu_si128(dst4+i+2)));
_mm_storeu_si128(dst4+i+3, SkPMSrcOver_SSE2(s3, _mm_loadu_si128(dst4+i+3)));
}
// Wrap up the last <= 15 pixels.
SkASSERT(count - (count16*16) <= 15);
for (int i = count16*16; i < count; i++) {
// This check is not really necessarily, but it prevents pointless autovectorization.
if (src[i] & 0xFF000000) {
dst[i] = SkPMSrcOver(src[i], dst[i]);
}
}
#endif
}
void S32A_Blend_BlitRow32_SSE2(SkPMColor* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha) {
SkASSERT(alpha <= 255);
if (count <= 0) {
return;
}
if (count >= 4) {
while (((size_t)dst & 0x0F) != 0) {
*dst = SkBlendARGB32(*src, *dst, alpha);
src++;
dst++;
count--;
}
const __m128i *s = reinterpret_cast<const __m128i*>(src);
__m128i *d = reinterpret_cast<__m128i*>(dst);
while (count >= 4) {
// Load 4 pixels each of src and dest.
__m128i src_pixel = _mm_loadu_si128(s);
__m128i dst_pixel = _mm_load_si128(d);
__m128i result = SkBlendARGB32_SSE2(src_pixel, dst_pixel, alpha);
_mm_store_si128(d, result);
s++;
d++;
count -= 4;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<SkPMColor*>(d);
}
while (count > 0) {
*dst = SkBlendARGB32(*src, *dst, alpha);
src++;
dst++;
count--;
}
}
void Color32A_D565_SSE2(uint16_t dst[], SkPMColor src, int count, int x, int y) {
SkASSERT(count > 0);
uint32_t src_expand = (SkGetPackedG32(src) << 24) |
(SkGetPackedR32(src) << 13) |
(SkGetPackedB32(src) << 2);
unsigned scale = SkAlpha255To256(0xFF - SkGetPackedA32(src)) >> 3;
// Check if we have enough pixels to run SIMD
if (count >= (int)(8 + (((16 - (size_t)dst) & 0x0F) >> 1))) {
__m128i* dst_wide;
const __m128i src_R_wide = _mm_set1_epi16(SkGetPackedR32(src) << 2);
const __m128i src_G_wide = _mm_set1_epi16(SkGetPackedG32(src) << 3);
const __m128i src_B_wide = _mm_set1_epi16(SkGetPackedB32(src) << 2);
const __m128i scale_wide = _mm_set1_epi16(scale);
const __m128i mask_blue = _mm_set1_epi16(SK_B16_MASK);
const __m128i mask_green = _mm_set1_epi16(SK_G16_MASK << SK_G16_SHIFT);
// Align dst to an even 16 byte address (0-7 pixels)
while (((((size_t)dst) & 0x0F) != 0) && (count > 0)) {
*dst = SkBlend32_RGB16(src_expand, *dst, scale);
dst += 1;
count--;
}
dst_wide = reinterpret_cast<__m128i*>(dst);
do {
// Load eight RGB565 pixels
__m128i pixels = _mm_load_si128(dst_wide);
// Mask out sub-pixels
__m128i pixel_R = _mm_srli_epi16(pixels, SK_R16_SHIFT);
__m128i pixel_G = _mm_slli_epi16(pixels, SK_R16_BITS);
pixel_G = _mm_srli_epi16(pixel_G, SK_R16_BITS + SK_B16_BITS);
__m128i pixel_B = _mm_and_si128(pixels, mask_blue);
// Scale with alpha
pixel_R = _mm_mullo_epi16(pixel_R, scale_wide);
pixel_G = _mm_mullo_epi16(pixel_G, scale_wide);
pixel_B = _mm_mullo_epi16(pixel_B, scale_wide);
// Add src_X_wide and shift down again
pixel_R = _mm_add_epi16(pixel_R, src_R_wide);
pixel_R = _mm_srli_epi16(pixel_R, 5);
pixel_G = _mm_add_epi16(pixel_G, src_G_wide);
pixel_B = _mm_add_epi16(pixel_B, src_B_wide);
pixel_B = _mm_srli_epi16(pixel_B, 5);
// Combine into RGB565 and store
pixel_R = _mm_slli_epi16(pixel_R, SK_R16_SHIFT);
pixel_G = _mm_and_si128(pixel_G, mask_green);
pixels = _mm_or_si128(pixel_R, pixel_G);
pixels = _mm_or_si128(pixels, pixel_B);
_mm_store_si128(dst_wide, pixels);
count -= 8;
dst_wide++;
} while (count >= 8);
dst = reinterpret_cast<uint16_t*>(dst_wide);
}
// Small loop to handle remaining pixels.
while (count > 0) {
*dst = SkBlend32_RGB16(src_expand, *dst, scale);
dst += 1;
count--;
}
}
// The following (left) shifts cause the top 5 bits of the mask components to
// line up with the corresponding components in an SkPMColor.
// Note that the mask's RGB16 order may differ from the SkPMColor order.
#define SK_R16x5_R32x5_SHIFT (SK_R32_SHIFT - SK_R16_SHIFT - SK_R16_BITS + 5)
#define SK_G16x5_G32x5_SHIFT (SK_G32_SHIFT - SK_G16_SHIFT - SK_G16_BITS + 5)
#define SK_B16x5_B32x5_SHIFT (SK_B32_SHIFT - SK_B16_SHIFT - SK_B16_BITS + 5)
#if SK_R16x5_R32x5_SHIFT == 0
#define SkPackedR16x5ToUnmaskedR32x5_SSE2(x) (x)
#elif SK_R16x5_R32x5_SHIFT > 0
#define SkPackedR16x5ToUnmaskedR32x5_SSE2(x) (_mm_slli_epi32(x, SK_R16x5_R32x5_SHIFT))
#else
#define SkPackedR16x5ToUnmaskedR32x5_SSE2(x) (_mm_srli_epi32(x, -SK_R16x5_R32x5_SHIFT))
#endif
#if SK_G16x5_G32x5_SHIFT == 0
#define SkPackedG16x5ToUnmaskedG32x5_SSE2(x) (x)
#elif SK_G16x5_G32x5_SHIFT > 0
#define SkPackedG16x5ToUnmaskedG32x5_SSE2(x) (_mm_slli_epi32(x, SK_G16x5_G32x5_SHIFT))
#else
#define SkPackedG16x5ToUnmaskedG32x5_SSE2(x) (_mm_srli_epi32(x, -SK_G16x5_G32x5_SHIFT))
#endif
#if SK_B16x5_B32x5_SHIFT == 0
#define SkPackedB16x5ToUnmaskedB32x5_SSE2(x) (x)
#elif SK_B16x5_B32x5_SHIFT > 0
#define SkPackedB16x5ToUnmaskedB32x5_SSE2(x) (_mm_slli_epi32(x, SK_B16x5_B32x5_SHIFT))
#else
#define SkPackedB16x5ToUnmaskedB32x5_SSE2(x) (_mm_srli_epi32(x, -SK_B16x5_B32x5_SHIFT))
#endif
static __m128i SkBlendLCD16_SSE2(__m128i &src, __m128i &dst,
__m128i &mask, __m128i &srcA) {
// In the following comments, the components of src, dst and mask are
// abbreviated as (s)rc, (d)st, and (m)ask. Color components are marked
// by an R, G, B, or A suffix. Components of one of the four pixels that
// are processed in parallel are marked with 0, 1, 2, and 3. "d1B", for
// example is the blue channel of the second destination pixel. Memory
// layout is shown for an ARGB byte order in a color value.
// src and srcA store 8-bit values interleaved with zeros.
// src = (0xFF, 0, sR, 0, sG, 0, sB, 0, 0xFF, 0, sR, 0, sG, 0, sB, 0)
// srcA = (srcA, 0, srcA, 0, srcA, 0, srcA, 0,
// srcA, 0, srcA, 0, srcA, 0, srcA, 0)
// mask stores 16-bit values (compressed three channels) interleaved with zeros.
// Lo and Hi denote the low and high bytes of a 16-bit value, respectively.
// mask = (m0RGBLo, m0RGBHi, 0, 0, m1RGBLo, m1RGBHi, 0, 0,
// m2RGBLo, m2RGBHi, 0, 0, m3RGBLo, m3RGBHi, 0, 0)
// Get the R,G,B of each 16bit mask pixel, we want all of them in 5 bits.
// r = (0, m0R, 0, 0, 0, m1R, 0, 0, 0, m2R, 0, 0, 0, m3R, 0, 0)
__m128i r = _mm_and_si128(SkPackedR16x5ToUnmaskedR32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_R32_SHIFT));
// g = (0, 0, m0G, 0, 0, 0, m1G, 0, 0, 0, m2G, 0, 0, 0, m3G, 0)
__m128i g = _mm_and_si128(SkPackedG16x5ToUnmaskedG32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_G32_SHIFT));
// b = (0, 0, 0, m0B, 0, 0, 0, m1B, 0, 0, 0, m2B, 0, 0, 0, m3B)
__m128i b = _mm_and_si128(SkPackedB16x5ToUnmaskedB32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_B32_SHIFT));
// Pack the 4 16bit mask pixels into 4 32bit pixels, (p0, p1, p2, p3)
// Each component (m0R, m0G, etc.) is then a 5-bit value aligned to an
// 8-bit position
// mask = (0, m0R, m0G, m0B, 0, m1R, m1G, m1B,
// 0, m2R, m2G, m2B, 0, m3R, m3G, m3B)
mask = _mm_or_si128(_mm_or_si128(r, g), b);
// Interleave R,G,B into the lower byte of word.
// i.e. split the sixteen 8-bit values from mask into two sets of eight
// 16-bit values, padded by zero.
__m128i maskLo, maskHi;
// maskLo = (0, 0, m0R, 0, m0G, 0, m0B, 0, 0, 0, m1R, 0, m1G, 0, m1B, 0)
maskLo = _mm_unpacklo_epi8(mask, _mm_setzero_si128());
// maskHi = (0, 0, m2R, 0, m2G, 0, m2B, 0, 0, 0, m3R, 0, m3G, 0, m3B, 0)
maskHi = _mm_unpackhi_epi8(mask, _mm_setzero_si128());
// Upscale from 0..31 to 0..32
// (allows to replace division by left-shift further down)
// Left-shift each component by 4 and add the result back to that component,
// mapping numbers in the range 0..15 to 0..15, and 16..31 to 17..32
maskLo = _mm_add_epi16(maskLo, _mm_srli_epi16(maskLo, 4));
maskHi = _mm_add_epi16(maskHi, _mm_srli_epi16(maskHi, 4));
// Multiply each component of maskLo and maskHi by srcA
maskLo = _mm_mullo_epi16(maskLo, srcA);
maskHi = _mm_mullo_epi16(maskHi, srcA);
// Left shift mask components by 8 (divide by 256)
maskLo = _mm_srli_epi16(maskLo, 8);
maskHi = _mm_srli_epi16(maskHi, 8);
// Interleave R,G,B into the lower byte of the word
// dstLo = (0, 0, d0R, 0, d0G, 0, d0B, 0, 0, 0, d1R, 0, d1G, 0, d1B, 0)
__m128i dstLo = _mm_unpacklo_epi8(dst, _mm_setzero_si128());
// dstLo = (0, 0, d2R, 0, d2G, 0, d2B, 0, 0, 0, d3R, 0, d3G, 0, d3B, 0)
__m128i dstHi = _mm_unpackhi_epi8(dst, _mm_setzero_si128());
// mask = (src - dst) * mask
maskLo = _mm_mullo_epi16(maskLo, _mm_sub_epi16(src, dstLo));
maskHi = _mm_mullo_epi16(maskHi, _mm_sub_epi16(src, dstHi));
// mask = (src - dst) * mask >> 5
maskLo = _mm_srai_epi16(maskLo, 5);
maskHi = _mm_srai_epi16(maskHi, 5);
// Add two pixels into result.
// result = dst + ((src - dst) * mask >> 5)
__m128i resultLo = _mm_add_epi16(dstLo, maskLo);
__m128i resultHi = _mm_add_epi16(dstHi, maskHi);
// Pack into 4 32bit dst pixels.
// resultLo and resultHi contain eight 16-bit components (two pixels) each.
// Merge into one SSE regsiter with sixteen 8-bit values (four pixels),
// clamping to 255 if necessary.
return _mm_packus_epi16(resultLo, resultHi);
}
static __m128i SkBlendLCD16Opaque_SSE2(__m128i &src, __m128i &dst,
__m128i &mask) {
// In the following comments, the components of src, dst and mask are
// abbreviated as (s)rc, (d)st, and (m)ask. Color components are marked
// by an R, G, B, or A suffix. Components of one of the four pixels that
// are processed in parallel are marked with 0, 1, 2, and 3. "d1B", for
// example is the blue channel of the second destination pixel. Memory
// layout is shown for an ARGB byte order in a color value.
// src and srcA store 8-bit values interleaved with zeros.
// src = (0xFF, 0, sR, 0, sG, 0, sB, 0, 0xFF, 0, sR, 0, sG, 0, sB, 0)
// mask stores 16-bit values (shown as high and low bytes) interleaved with
// zeros
// mask = (m0RGBLo, m0RGBHi, 0, 0, m1RGBLo, m1RGBHi, 0, 0,
// m2RGBLo, m2RGBHi, 0, 0, m3RGBLo, m3RGBHi, 0, 0)
// Get the R,G,B of each 16bit mask pixel, we want all of them in 5 bits.
// r = (0, m0R, 0, 0, 0, m1R, 0, 0, 0, m2R, 0, 0, 0, m3R, 0, 0)
__m128i r = _mm_and_si128(SkPackedR16x5ToUnmaskedR32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_R32_SHIFT));
// g = (0, 0, m0G, 0, 0, 0, m1G, 0, 0, 0, m2G, 0, 0, 0, m3G, 0)
__m128i g = _mm_and_si128(SkPackedG16x5ToUnmaskedG32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_G32_SHIFT));
// b = (0, 0, 0, m0B, 0, 0, 0, m1B, 0, 0, 0, m2B, 0, 0, 0, m3B)
__m128i b = _mm_and_si128(SkPackedB16x5ToUnmaskedB32x5_SSE2(mask),
_mm_set1_epi32(0x1F << SK_B32_SHIFT));
// Pack the 4 16bit mask pixels into 4 32bit pixels, (p0, p1, p2, p3)
// Each component (m0R, m0G, etc.) is then a 5-bit value aligned to an
// 8-bit position
// mask = (0, m0R, m0G, m0B, 0, m1R, m1G, m1B,
// 0, m2R, m2G, m2B, 0, m3R, m3G, m3B)
mask = _mm_or_si128(_mm_or_si128(r, g), b);
// Interleave R,G,B into the lower byte of word.
// i.e. split the sixteen 8-bit values from mask into two sets of eight
// 16-bit values, padded by zero.
__m128i maskLo, maskHi;
// maskLo = (0, 0, m0R, 0, m0G, 0, m0B, 0, 0, 0, m1R, 0, m1G, 0, m1B, 0)
maskLo = _mm_unpacklo_epi8(mask, _mm_setzero_si128());
// maskHi = (0, 0, m2R, 0, m2G, 0, m2B, 0, 0, 0, m3R, 0, m3G, 0, m3B, 0)
maskHi = _mm_unpackhi_epi8(mask, _mm_setzero_si128());
// Upscale from 0..31 to 0..32
// (allows to replace division by left-shift further down)
// Left-shift each component by 4 and add the result back to that component,
// mapping numbers in the range 0..15 to 0..15, and 16..31 to 17..32
maskLo = _mm_add_epi16(maskLo, _mm_srli_epi16(maskLo, 4));
maskHi = _mm_add_epi16(maskHi, _mm_srli_epi16(maskHi, 4));
// Interleave R,G,B into the lower byte of the word
// dstLo = (0, 0, d0R, 0, d0G, 0, d0B, 0, 0, 0, d1R, 0, d1G, 0, d1B, 0)
__m128i dstLo = _mm_unpacklo_epi8(dst, _mm_setzero_si128());
// dstLo = (0, 0, d2R, 0, d2G, 0, d2B, 0, 0, 0, d3R, 0, d3G, 0, d3B, 0)
__m128i dstHi = _mm_unpackhi_epi8(dst, _mm_setzero_si128());
// mask = (src - dst) * mask
maskLo = _mm_mullo_epi16(maskLo, _mm_sub_epi16(src, dstLo));
maskHi = _mm_mullo_epi16(maskHi, _mm_sub_epi16(src, dstHi));
// mask = (src - dst) * mask >> 5
maskLo = _mm_srai_epi16(maskLo, 5);
maskHi = _mm_srai_epi16(maskHi, 5);
// Add two pixels into result.
// result = dst + ((src - dst) * mask >> 5)
__m128i resultLo = _mm_add_epi16(dstLo, maskLo);
__m128i resultHi = _mm_add_epi16(dstHi, maskHi);
// Pack into 4 32bit dst pixels and force opaque.
// resultLo and resultHi contain eight 16-bit components (two pixels) each.
// Merge into one SSE regsiter with sixteen 8-bit values (four pixels),
// clamping to 255 if necessary. Set alpha components to 0xFF.
return _mm_or_si128(_mm_packus_epi16(resultLo, resultHi),
_mm_set1_epi32(SK_A32_MASK << SK_A32_SHIFT));
}
void SkBlitLCD16Row_SSE2(SkPMColor dst[], const uint16_t mask[],
SkColor src, int width, SkPMColor) {
if (width <= 0) {
return;
}
int srcA = SkColorGetA(src);
int srcR = SkColorGetR(src);
int srcG = SkColorGetG(src);
int srcB = SkColorGetB(src);
srcA = SkAlpha255To256(srcA);
if (width >= 4) {
SkASSERT(((size_t)dst & 0x03) == 0);
while (((size_t)dst & 0x0F) != 0) {
*dst = SkBlendLCD16(srcA, srcR, srcG, srcB, *dst, *mask);
mask++;
dst++;
width--;
}
__m128i *d = reinterpret_cast<__m128i*>(dst);
// Set alpha to 0xFF and replicate source four times in SSE register.
__m128i src_sse = _mm_set1_epi32(SkPackARGB32(0xFF, srcR, srcG, srcB));
// Interleave with zeros to get two sets of four 16-bit values.
src_sse = _mm_unpacklo_epi8(src_sse, _mm_setzero_si128());
// Set srcA_sse to contain eight copies of srcA, padded with zero.
// src_sse=(0xFF, 0, sR, 0, sG, 0, sB, 0, 0xFF, 0, sR, 0, sG, 0, sB, 0)
__m128i srcA_sse = _mm_set1_epi16(srcA);
while (width >= 4) {
// Load four destination pixels into dst_sse.
__m128i dst_sse = _mm_load_si128(d);
// Load four 16-bit masks into lower half of mask_sse.
__m128i mask_sse = _mm_loadl_epi64(
reinterpret_cast<const __m128i*>(mask));
// Check whether masks are equal to 0 and get the highest bit
// of each byte of result, if masks are all zero, we will get
// pack_cmp to 0xFFFF
int pack_cmp = _mm_movemask_epi8(_mm_cmpeq_epi16(mask_sse,
_mm_setzero_si128()));
// if mask pixels are not all zero, we will blend the dst pixels
if (pack_cmp != 0xFFFF) {
// Unpack 4 16bit mask pixels to
// mask_sse = (m0RGBLo, m0RGBHi, 0, 0, m1RGBLo, m1RGBHi, 0, 0,
// m2RGBLo, m2RGBHi, 0, 0, m3RGBLo, m3RGBHi, 0, 0)
mask_sse = _mm_unpacklo_epi16(mask_sse,
_mm_setzero_si128());
// Process 4 32bit dst pixels
__m128i result = SkBlendLCD16_SSE2(src_sse, dst_sse,
mask_sse, srcA_sse);
_mm_store_si128(d, result);
}
d++;
mask += 4;
width -= 4;
}
dst = reinterpret_cast<SkPMColor*>(d);
}
while (width > 0) {
*dst = SkBlendLCD16(srcA, srcR, srcG, srcB, *dst, *mask);
mask++;
dst++;
width--;
}
}
void SkBlitLCD16OpaqueRow_SSE2(SkPMColor dst[], const uint16_t mask[],
SkColor src, int width, SkPMColor opaqueDst) {
if (width <= 0) {
return;
}
int srcR = SkColorGetR(src);
int srcG = SkColorGetG(src);
int srcB = SkColorGetB(src);
if (width >= 4) {
SkASSERT(((size_t)dst & 0x03) == 0);
while (((size_t)dst & 0x0F) != 0) {
*dst = SkBlendLCD16Opaque(srcR, srcG, srcB, *dst, *mask, opaqueDst);
mask++;
dst++;
width--;
}
__m128i *d = reinterpret_cast<__m128i*>(dst);
// Set alpha to 0xFF and replicate source four times in SSE register.
__m128i src_sse = _mm_set1_epi32(SkPackARGB32(0xFF, srcR, srcG, srcB));
// Set srcA_sse to contain eight copies of srcA, padded with zero.
// src_sse=(0xFF, 0, sR, 0, sG, 0, sB, 0, 0xFF, 0, sR, 0, sG, 0, sB, 0)
src_sse = _mm_unpacklo_epi8(src_sse, _mm_setzero_si128());
while (width >= 4) {
// Load four destination pixels into dst_sse.
__m128i dst_sse = _mm_load_si128(d);
// Load four 16-bit masks into lower half of mask_sse.
__m128i mask_sse = _mm_loadl_epi64(
reinterpret_cast<const __m128i*>(mask));
// Check whether masks are equal to 0 and get the highest bit
// of each byte of result, if masks are all zero, we will get
// pack_cmp to 0xFFFF
int pack_cmp = _mm_movemask_epi8(_mm_cmpeq_epi16(mask_sse,
_mm_setzero_si128()));
// if mask pixels are not all zero, we will blend the dst pixels
if (pack_cmp != 0xFFFF) {
// Unpack 4 16bit mask pixels to
// mask_sse = (m0RGBLo, m0RGBHi, 0, 0, m1RGBLo, m1RGBHi, 0, 0,
// m2RGBLo, m2RGBHi, 0, 0, m3RGBLo, m3RGBHi, 0, 0)
mask_sse = _mm_unpacklo_epi16(mask_sse,
_mm_setzero_si128());
// Process 4 32bit dst pixels
__m128i result = SkBlendLCD16Opaque_SSE2(src_sse, dst_sse,
mask_sse);
_mm_store_si128(d, result);
}
d++;
mask += 4;
width -= 4;
}
dst = reinterpret_cast<SkPMColor*>(d);
}
while (width > 0) {
*dst = SkBlendLCD16Opaque(srcR, srcG, srcB, *dst, *mask, opaqueDst);
mask++;
dst++;
width--;
}
}
/* SSE2 version of S32_D565_Opaque()
* portable version is in core/SkBlitRow_D16.cpp
*/
void S32_D565_Opaque_SSE2(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src, int count,
U8CPU alpha, int /*x*/, int /*y*/) {
SkASSERT(255 == alpha);
if (count <= 0) {
return;
}
if (count >= 8) {
while (((size_t)dst & 0x0F) != 0) {
SkPMColor c = *src++;
SkPMColorAssert(c);
*dst++ = SkPixel32ToPixel16_ToU16(c);
count--;
}
const __m128i* s = reinterpret_cast<const __m128i*>(src);
__m128i* d = reinterpret_cast<__m128i*>(dst);
while (count >= 8) {
// Load 8 pixels of src.
__m128i src_pixel1 = _mm_loadu_si128(s++);
__m128i src_pixel2 = _mm_loadu_si128(s++);
__m128i d_pixel = SkPixel32ToPixel16_ToU16_SSE2(src_pixel1, src_pixel2);
_mm_store_si128(d++, d_pixel);
count -= 8;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<uint16_t*>(d);
}
if (count > 0) {
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
*dst++ = SkPixel32ToPixel16_ToU16(c);
} while (--count != 0);
}
}
/* SSE2 version of S32A_D565_Opaque()
* portable version is in core/SkBlitRow_D16.cpp
*/
void S32A_D565_Opaque_SSE2(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha, int /*x*/, int /*y*/) {
SkASSERT(255 == alpha);
if (count <= 0) {
return;
}
if (count >= 8) {
// Make dst 16 bytes alignment
while (((size_t)dst & 0x0F) != 0) {
SkPMColor c = *src++;
if (c) {
*dst = SkSrcOver32To16(c, *dst);
}
dst += 1;
count--;
}
const __m128i* s = reinterpret_cast<const __m128i*>(src);
__m128i* d = reinterpret_cast<__m128i*>(dst);
__m128i var255 = _mm_set1_epi16(255);
__m128i r16_mask = _mm_set1_epi16(SK_R16_MASK);
__m128i g16_mask = _mm_set1_epi16(SK_G16_MASK);
__m128i b16_mask = _mm_set1_epi16(SK_B16_MASK);
while (count >= 8) {
// Load 8 pixels of src.
__m128i src_pixel1 = _mm_loadu_si128(s++);
__m128i src_pixel2 = _mm_loadu_si128(s++);
// Check whether src pixels are equal to 0 and get the highest bit
// of each byte of result, if src pixels are all zero, src_cmp1 and
// src_cmp2 will be 0xFFFF.
int src_cmp1 = _mm_movemask_epi8(_mm_cmpeq_epi16(src_pixel1,
_mm_setzero_si128()));
int src_cmp2 = _mm_movemask_epi8(_mm_cmpeq_epi16(src_pixel2,
_mm_setzero_si128()));
if (src_cmp1 == 0xFFFF && src_cmp2 == 0xFFFF) {
d++;
count -= 8;
continue;
}
// Load 8 pixels of dst.
__m128i dst_pixel = _mm_load_si128(d);
// Extract A from src.
__m128i sa1 = _mm_slli_epi32(src_pixel1, (24 - SK_A32_SHIFT));
sa1 = _mm_srli_epi32(sa1, 24);
__m128i sa2 = _mm_slli_epi32(src_pixel2, (24 - SK_A32_SHIFT));
sa2 = _mm_srli_epi32(sa2, 24);
__m128i sa = _mm_packs_epi32(sa1, sa2);
// Extract R from src.
__m128i sr1 = _mm_slli_epi32(src_pixel1, (24 - SK_R32_SHIFT));
sr1 = _mm_srli_epi32(sr1, 24);
__m128i sr2 = _mm_slli_epi32(src_pixel2, (24 - SK_R32_SHIFT));
sr2 = _mm_srli_epi32(sr2, 24);
__m128i sr = _mm_packs_epi32(sr1, sr2);
// Extract G from src.
__m128i sg1 = _mm_slli_epi32(src_pixel1, (24 - SK_G32_SHIFT));
sg1 = _mm_srli_epi32(sg1, 24);
__m128i sg2 = _mm_slli_epi32(src_pixel2, (24 - SK_G32_SHIFT));
sg2 = _mm_srli_epi32(sg2, 24);
__m128i sg = _mm_packs_epi32(sg1, sg2);
// Extract B from src.
__m128i sb1 = _mm_slli_epi32(src_pixel1, (24 - SK_B32_SHIFT));
sb1 = _mm_srli_epi32(sb1, 24);
__m128i sb2 = _mm_slli_epi32(src_pixel2, (24 - SK_B32_SHIFT));
sb2 = _mm_srli_epi32(sb2, 24);
__m128i sb = _mm_packs_epi32(sb1, sb2);
// Extract R G B from dst.
__m128i dr = _mm_srli_epi16(dst_pixel, SK_R16_SHIFT);
dr = _mm_and_si128(dr, r16_mask);
__m128i dg = _mm_srli_epi16(dst_pixel, SK_G16_SHIFT);
dg = _mm_and_si128(dg, g16_mask);
__m128i db = _mm_srli_epi16(dst_pixel, SK_B16_SHIFT);
db = _mm_and_si128(db, b16_mask);
__m128i isa = _mm_sub_epi16(var255, sa); // 255 -sa
// Calculate R G B of result.
// Original algorithm is in SkSrcOver32To16().
dr = _mm_add_epi16(sr, SkMul16ShiftRound_SSE2(dr, isa, SK_R16_BITS));
dr = _mm_srli_epi16(dr, 8 - SK_R16_BITS);
dg = _mm_add_epi16(sg, SkMul16ShiftRound_SSE2(dg, isa, SK_G16_BITS));
dg = _mm_srli_epi16(dg, 8 - SK_G16_BITS);
db = _mm_add_epi16(sb, SkMul16ShiftRound_SSE2(db, isa, SK_B16_BITS));
db = _mm_srli_epi16(db, 8 - SK_B16_BITS);
// Pack R G B into 16-bit color.
__m128i d_pixel = SkPackRGB16_SSE2(dr, dg, db);
// Store 8 16-bit colors in dst.
_mm_store_si128(d++, d_pixel);
count -= 8;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<uint16_t*>(d);
}
if (count > 0) {
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
if (c) {
*dst = SkSrcOver32To16(c, *dst);
}
dst += 1;
} while (--count != 0);
}
}
void S32_D565_Opaque_Dither_SSE2(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha, int x, int y) {
SkASSERT(255 == alpha);
if (count <= 0) {
return;
}
if (count >= 8) {
while (((size_t)dst & 0x0F) != 0) {
DITHER_565_SCAN(y);
SkPMColor c = *src++;
SkPMColorAssert(c);
unsigned dither = DITHER_VALUE(x);
*dst++ = SkDitherRGB32To565(c, dither);
DITHER_INC_X(x);
count--;
}
unsigned short dither_value[8];
__m128i dither;
#ifdef ENABLE_DITHER_MATRIX_4X4
const uint8_t* dither_scan = gDitherMatrix_3Bit_4X4[(y) & 3];
dither_value[0] = dither_value[4] = dither_scan[(x) & 3];
dither_value[1] = dither_value[5] = dither_scan[(x + 1) & 3];
dither_value[2] = dither_value[6] = dither_scan[(x + 2) & 3];
dither_value[3] = dither_value[7] = dither_scan[(x + 3) & 3];
#else
const uint16_t dither_scan = gDitherMatrix_3Bit_16[(y) & 3];
dither_value[0] = dither_value[4] = (dither_scan
>> (((x) & 3) << 2)) & 0xF;
dither_value[1] = dither_value[5] = (dither_scan
>> (((x + 1) & 3) << 2)) & 0xF;
dither_value[2] = dither_value[6] = (dither_scan
>> (((x + 2) & 3) << 2)) & 0xF;
dither_value[3] = dither_value[7] = (dither_scan
>> (((x + 3) & 3) << 2)) & 0xF;
#endif
dither = _mm_loadu_si128((__m128i*) dither_value);
const __m128i* s = reinterpret_cast<const __m128i*>(src);
__m128i* d = reinterpret_cast<__m128i*>(dst);
while (count >= 8) {
// Load 8 pixels of src.
__m128i src_pixel1 = _mm_loadu_si128(s++);
__m128i src_pixel2 = _mm_loadu_si128(s++);
// Extract R from src.
__m128i sr1 = _mm_slli_epi32(src_pixel1, (24 - SK_R32_SHIFT));
sr1 = _mm_srli_epi32(sr1, 24);
__m128i sr2 = _mm_slli_epi32(src_pixel2, (24 - SK_R32_SHIFT));
sr2 = _mm_srli_epi32(sr2, 24);
__m128i sr = _mm_packs_epi32(sr1, sr2);
// SkDITHER_R32To565(sr, dither)
__m128i sr_offset = _mm_srli_epi16(sr, 5);
sr = _mm_add_epi16(sr, dither);
sr = _mm_sub_epi16(sr, sr_offset);
sr = _mm_srli_epi16(sr, SK_R32_BITS - SK_R16_BITS);
// Extract G from src.
__m128i sg1 = _mm_slli_epi32(src_pixel1, (24 - SK_G32_SHIFT));
sg1 = _mm_srli_epi32(sg1, 24);
__m128i sg2 = _mm_slli_epi32(src_pixel2, (24 - SK_G32_SHIFT));
sg2 = _mm_srli_epi32(sg2, 24);
__m128i sg = _mm_packs_epi32(sg1, sg2);
// SkDITHER_R32To565(sg, dither)
__m128i sg_offset = _mm_srli_epi16(sg, 6);
sg = _mm_add_epi16(sg, _mm_srli_epi16(dither, 1));
sg = _mm_sub_epi16(sg, sg_offset);
sg = _mm_srli_epi16(sg, SK_G32_BITS - SK_G16_BITS);
// Extract B from src.
__m128i sb1 = _mm_slli_epi32(src_pixel1, (24 - SK_B32_SHIFT));
sb1 = _mm_srli_epi32(sb1, 24);
__m128i sb2 = _mm_slli_epi32(src_pixel2, (24 - SK_B32_SHIFT));
sb2 = _mm_srli_epi32(sb2, 24);
__m128i sb = _mm_packs_epi32(sb1, sb2);
// SkDITHER_R32To565(sb, dither)
__m128i sb_offset = _mm_srli_epi16(sb, 5);
sb = _mm_add_epi16(sb, dither);
sb = _mm_sub_epi16(sb, sb_offset);
sb = _mm_srli_epi16(sb, SK_B32_BITS - SK_B16_BITS);
// Pack and store 16-bit dst pixel.
__m128i d_pixel = SkPackRGB16_SSE2(sr, sg, sb);
_mm_store_si128(d++, d_pixel);
count -= 8;
x += 8;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<uint16_t*>(d);
}
if (count > 0) {
DITHER_565_SCAN(y);
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
unsigned dither = DITHER_VALUE(x);
*dst++ = SkDitherRGB32To565(c, dither);
DITHER_INC_X(x);
} while (--count != 0);
}
}
/* SSE2 version of S32A_D565_Opaque_Dither()
* portable version is in core/SkBlitRow_D16.cpp
*/
void S32A_D565_Opaque_Dither_SSE2(uint16_t* SK_RESTRICT dst,
const SkPMColor* SK_RESTRICT src,
int count, U8CPU alpha, int x, int y) {
SkASSERT(255 == alpha);
if (count <= 0) {
return;
}
if (count >= 8) {
while (((size_t)dst & 0x0F) != 0) {
DITHER_565_SCAN(y);
SkPMColor c = *src++;
SkPMColorAssert(c);
if (c) {
unsigned a = SkGetPackedA32(c);
int d = SkAlphaMul(DITHER_VALUE(x), SkAlpha255To256(a));
unsigned sr = SkGetPackedR32(c);
unsigned sg = SkGetPackedG32(c);
unsigned sb = SkGetPackedB32(c);
sr = SkDITHER_R32_FOR_565(sr, d);
sg = SkDITHER_G32_FOR_565(sg, d);
sb = SkDITHER_B32_FOR_565(sb, d);
uint32_t src_expanded = (sg << 24) | (sr << 13) | (sb << 2);
uint32_t dst_expanded = SkExpand_rgb_16(*dst);
dst_expanded = dst_expanded * (SkAlpha255To256(255 - a) >> 3);
// now src and dst expanded are in g:11 r:10 x:1 b:10
*dst = SkCompact_rgb_16((src_expanded + dst_expanded) >> 5);
}
dst += 1;
DITHER_INC_X(x);
count--;
}
unsigned short dither_value[8];
__m128i dither, dither_cur;
#ifdef ENABLE_DITHER_MATRIX_4X4
const uint8_t* dither_scan = gDitherMatrix_3Bit_4X4[(y) & 3];
dither_value[0] = dither_value[4] = dither_scan[(x) & 3];
dither_value[1] = dither_value[5] = dither_scan[(x + 1) & 3];
dither_value[2] = dither_value[6] = dither_scan[(x + 2) & 3];
dither_value[3] = dither_value[7] = dither_scan[(x + 3) & 3];
#else
const uint16_t dither_scan = gDitherMatrix_3Bit_16[(y) & 3];
dither_value[0] = dither_value[4] = (dither_scan
>> (((x) & 3) << 2)) & 0xF;
dither_value[1] = dither_value[5] = (dither_scan
>> (((x + 1) & 3) << 2)) & 0xF;
dither_value[2] = dither_value[6] = (dither_scan
>> (((x + 2) & 3) << 2)) & 0xF;
dither_value[3] = dither_value[7] = (dither_scan
>> (((x + 3) & 3) << 2)) & 0xF;
#endif
dither = _mm_loadu_si128((__m128i*) dither_value);
const __m128i* s = reinterpret_cast<const __m128i*>(src);
__m128i* d = reinterpret_cast<__m128i*>(dst);
__m128i var256 = _mm_set1_epi16(256);
__m128i r16_mask = _mm_set1_epi16(SK_R16_MASK);
__m128i g16_mask = _mm_set1_epi16(SK_G16_MASK);
__m128i b16_mask = _mm_set1_epi16(SK_B16_MASK);
while (count >= 8) {
// Load 8 pixels of src and dst.
__m128i src_pixel1 = _mm_loadu_si128(s++);
__m128i src_pixel2 = _mm_loadu_si128(s++);
__m128i dst_pixel = _mm_load_si128(d);
// Extract A from src.
__m128i sa1 = _mm_slli_epi32(src_pixel1, (24 - SK_A32_SHIFT));
sa1 = _mm_srli_epi32(sa1, 24);
__m128i sa2 = _mm_slli_epi32(src_pixel2, (24 - SK_A32_SHIFT));
sa2 = _mm_srli_epi32(sa2, 24);
__m128i sa = _mm_packs_epi32(sa1, sa2);
// Calculate current dither value.
dither_cur = _mm_mullo_epi16(dither,
_mm_add_epi16(sa, _mm_set1_epi16(1)));
dither_cur = _mm_srli_epi16(dither_cur, 8);
// Extract R from src.
__m128i sr1 = _mm_slli_epi32(src_pixel1, (24 - SK_R32_SHIFT));
sr1 = _mm_srli_epi32(sr1, 24);
__m128i sr2 = _mm_slli_epi32(src_pixel2, (24 - SK_R32_SHIFT));
sr2 = _mm_srli_epi32(sr2, 24);
__m128i sr = _mm_packs_epi32(sr1, sr2);
// SkDITHER_R32_FOR_565(sr, d)
__m128i sr_offset = _mm_srli_epi16(sr, 5);
sr = _mm_add_epi16(sr, dither_cur);
sr = _mm_sub_epi16(sr, sr_offset);
// Expand sr.
sr = _mm_slli_epi16(sr, 2);
// Extract G from src.
__m128i sg1 = _mm_slli_epi32(src_pixel1, (24 - SK_G32_SHIFT));
sg1 = _mm_srli_epi32(sg1, 24);
__m128i sg2 = _mm_slli_epi32(src_pixel2, (24 - SK_G32_SHIFT));
sg2 = _mm_srli_epi32(sg2, 24);
__m128i sg = _mm_packs_epi32(sg1, sg2);
// sg = SkDITHER_G32_FOR_565(sg, d).
__m128i sg_offset = _mm_srli_epi16(sg, 6);
sg = _mm_add_epi16(sg, _mm_srli_epi16(dither_cur, 1));
sg = _mm_sub_epi16(sg, sg_offset);
// Expand sg.
sg = _mm_slli_epi16(sg, 3);
// Extract B from src.
__m128i sb1 = _mm_slli_epi32(src_pixel1, (24 - SK_B32_SHIFT));
sb1 = _mm_srli_epi32(sb1, 24);
__m128i sb2 = _mm_slli_epi32(src_pixel2, (24 - SK_B32_SHIFT));
sb2 = _mm_srli_epi32(sb2, 24);
__m128i sb = _mm_packs_epi32(sb1, sb2);
// sb = SkDITHER_B32_FOR_565(sb, d).
__m128i sb_offset = _mm_srli_epi16(sb, 5);
sb = _mm_add_epi16(sb, dither_cur);
sb = _mm_sub_epi16(sb, sb_offset);
// Expand sb.
sb = _mm_slli_epi16(sb, 2);
// Extract R G B from dst.
__m128i dr = _mm_srli_epi16(dst_pixel, SK_R16_SHIFT);
dr = _mm_and_si128(dr, r16_mask);
__m128i dg = _mm_srli_epi16(dst_pixel, SK_G16_SHIFT);
dg = _mm_and_si128(dg, g16_mask);
__m128i db = _mm_srli_epi16(dst_pixel, SK_B16_SHIFT);
db = _mm_and_si128(db, b16_mask);
// SkAlpha255To256(255 - a) >> 3
__m128i isa = _mm_sub_epi16(var256, sa);
isa = _mm_srli_epi16(isa, 3);
dr = _mm_mullo_epi16(dr, isa);
dr = _mm_add_epi16(dr, sr);
dr = _mm_srli_epi16(dr, 5);
dg = _mm_mullo_epi16(dg, isa);
dg = _mm_add_epi16(dg, sg);
dg = _mm_srli_epi16(dg, 5);
db = _mm_mullo_epi16(db, isa);
db = _mm_add_epi16(db, sb);
db = _mm_srli_epi16(db, 5);
// Package and store dst pixel.
__m128i d_pixel = SkPackRGB16_SSE2(dr, dg, db);
_mm_store_si128(d++, d_pixel);
count -= 8;
x += 8;
}
src = reinterpret_cast<const SkPMColor*>(s);
dst = reinterpret_cast<uint16_t*>(d);
}
if (count > 0) {
DITHER_565_SCAN(y);
do {
SkPMColor c = *src++;
SkPMColorAssert(c);
if (c) {
unsigned a = SkGetPackedA32(c);
int d = SkAlphaMul(DITHER_VALUE(x), SkAlpha255To256(a));
unsigned sr = SkGetPackedR32(c);
unsigned sg = SkGetPackedG32(c);
unsigned sb = SkGetPackedB32(c);
sr = SkDITHER_R32_FOR_565(sr, d);
sg = SkDITHER_G32_FOR_565(sg, d);
sb = SkDITHER_B32_FOR_565(sb, d);
uint32_t src_expanded = (sg << 24) | (sr << 13) | (sb << 2);
uint32_t dst_expanded = SkExpand_rgb_16(*dst);
dst_expanded = dst_expanded * (SkAlpha255To256(255 - a) >> 3);
// now src and dst expanded are in g:11 r:10 x:1 b:10
*dst = SkCompact_rgb_16((src_expanded + dst_expanded) >> 5);
}
dst += 1;
DITHER_INC_X(x);
} while (--count != 0);
}
}