skia2/third_party/libpng/contrib/intel/intel_init.c
scroggo 3965825b97 Check libpng directly into third_party/
With this change, the CMake build, which does not use DEPS to sync
external projects, is able to build and use the same version of libpng
that is used in other builds.

This will allow all platforms (including Google3 CMake build) to test on
the same version of libpng, so we do not need to make SkPngCodec support
all versions of libpng.

- Update CMakeLists.txt to use the checked in libpng.
- Check in libpng version 1.6.22rc01
- Update README.google
- Replace our old LICENSE file with the latest one from libpng
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2033063003
CQ_EXTRA_TRYBOTS=client.skia.compile:Build-Ubuntu-GCC-x86_64-Release-CMake-Trybot,Build-Mac-Clang-x86_64-Release-CMake-Trybot

Review-Url: https://codereview.chromium.org/2033063003
2016-06-02 12:59:59 -07:00

55 lines
1.8 KiB
C

/* intel_init.c - SSE2 optimized filter functions
*
* Copyright (c) 2016 Google, Inc.
* Written by Mike Klein and Matt Sarett
* Derived from arm/arm_init.c, which was
* Copyright (c) 2014,2016 Glenn Randers-Pehrson
*
* Last changed in libpng 1.6.22 [(PENDING RELEASE)]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*/
#include "../../pngpriv.h"
#ifdef PNG_READ_SUPPORTED
#if PNG_INTEL_SSE_IMPLEMENTATION > 0
void
png_init_filter_functions_sse2(png_structp pp, unsigned int bpp)
{
/* The techniques used to implement each of these filters in SSE operate on
* one pixel at a time.
* So they generally speed up 3bpp images about 3x, 4bpp images about 4x.
* They can scale up to 6 and 8 bpp images and down to 2 bpp images,
* but they'd not likely have any benefit for 1bpp images.
* Most of these can be implemented using only MMX and 64-bit registers,
* but they end up a bit slower than using the equally-ubiquitous SSE2.
*/
png_debug(1, "in png_init_filter_functions_sse2");
if (bpp == 3)
{
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_sse2;
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_sse2;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
png_read_filter_row_paeth3_sse2;
}
else if (bpp == 4)
{
pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_sse2;
pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_sse2;
pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
png_read_filter_row_paeth4_sse2;
}
/* No need optimize PNG_FILTER_VALUE_UP. The compiler should
* autovectorize.
*/
}
#endif /* PNG_INTEL_SSE_IMPLEMENTATION > 0 */
#endif /* PNG_READ_SUPPORTED */