[libpng16] Moved SSE2 optimization code into the main libpng source directory.

Configure libpng with "configure --enable-intel-sse" or compile
libpng with "-DPNG_INTEL_SSE" in CPPFLAGS to enable it.  This patch was
previously applied to libpng-1.6.28rc03 but withdrawn to allow time for QA.

ANNOUNCE

-Libpng 1.6.29beta01 - January 5, 2017
+Libpng 1.6.29beta01 - January 6, 2017
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -25,8 +25,11 @@ Other information:
 
 Changes since the last public release (1.6.28):
 
-Version 1.6.29beta01 [January 5, 2017]
+Version 1.6.29beta01 [January 6, 2017]
   Readded "include(GNUInstallDirs)" to CMakeLists.txt (Gianfranco Costamagna).
+  Moved SSE2 optimization code into the main libpng source directory.
+    Configure libpng with "configure --enable-intel-sse" or compile
+    libpng with "-DPNG_INTEL_SSE" in CPPFLAGS to enable it.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CHANGES

@@ -5794,8 +5794,11 @@ Version 1.6.28rc03 [January 4, 2017]
 Version 1.6.28 [January 5, 2017]
   No changes.
 
-Version 1.6.29beta01 [January 5, 2017]
+Version 1.6.29beta01 [January 6, 2017]
   Readded "include(GNUInstallDirs)" to CMakeLists.txt (Gianfranco Costamagna).
+  Moved SSE2 optimization code into the main libpng source directory.
+    Configure libpng with "configure --enable-intel-sse" or compile
+    libpng with "-DPNG_INTEL_SSE" in CPPFLAGS to enable it.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

contrib/intel/INSTALL

-Enabling SSE support
-
-Copyright (c) 2016 Google, Inc.
-Written by Mike Klein, Matt Sarett
-
-This INSTALL file written by Glenn Randers-Pehrson, 2016.
-
-If you have moved intel_init.c and filter_sse2_intrinsics.c to a different
-directory, be sure to update the '#include "../../pngpriv.h"' line in both
-files if necessary to point to the correct relative location of pngpriv.h
-with respect to the new location of those files.
-
-To enable SSE support in libpng, follow the instructions in I, II, or III,
-below:
-
-I. Using patched "configure" scripts:
-
-First, apply intel_sse.patch in your build directory.
-
-   patch -i contrib/intel/intel_sse.patch -p1
-
-Then, if you are not building in a new GIT clone, e.g., in a tar
-distribution, remove any existing pre-built configure scripts:
-
-   ./configure --enable-maintainer-mode
-   make maintainer-clean
-   ./autogen.sh --maintainer --clean
-
-Finally, configure libpng with -DPNG_INTEL_SSE in CPPFLAGS:
-
-   ./autogen.sh --maintainer
-   CPPFLAGS="-DPNG_INTEL_SSE" ./configure [options]
-   make CPPFLAGS="-DPNG_INTEL_SSE" [options]
-   make
-
-II. Using a custom makefile:
-
-If you are using a custom makefile makefile, you will have to update it
-manually to include contrib/intel/*.o in the dependencies, and to define
-PNG_INTEL_SSE.
-
-III. Using manually updated "configure" scripts:
-
-If you prefer, manually edit pngpriv.h, configure.ac, and Makefile.am,
-following the instructions below, then follow the instructions in
-section II of INSTALL in the main libpng directory, then configure libpng
-with -DPNG_INTEL_SSE in CPPFLAGS.
-
-1. Add the following code to configure.ac under HOST SPECIFIC OPTIONS
-directly beneath the section for ARM:
-
------------------cut----------------
-# INTEL
-# =====
-#
-# INTEL SSE (SIMD) support.
-
-AC_ARG_ENABLE([intel-sse],
-   AS_HELP_STRING([[[--enable-intel-sse]]],
-      [Enable Intel SSE optimizations: =no/off, yes/on:]
-      [no/off: disable the optimizations;]
-      [yes/on: enable the optimizations.]
-      [If not specified: determined by the compiler.]),
-   [case "$enableval" in
-      no|off)
-         # disable the default enabling:
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-                   [Disable Intel SSE optimizations])
-         # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
-      yes|on)
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-                   [Enable Intel SSE optimizations]);;
-      *)
-         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
-   esac])
-
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
-AM_CONDITIONAL([PNG_INTEL_SSE],
-   [test "$enable_intel_sse" != 'no' &&
-    case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
-    esac])
------------------cut----------------
-
-2. Add the following code to Makefile.am under HOST SPECIFIC OPTIONS
-directly beneath the "if PNG_ARM_NEON ... endif" statement:
-
------------------cut----------------
-if PNG_INTEL_SSE
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += contrib/intel/intel_init.c\
-    contrib/intel/filter_sse2_intrinsics.c
-endif
------------------cut----------------
-
-3. Add the following lines to pngpriv.h, following the PNG_ARM_NEON_OPT
-code:
-
------------------cut----------------
-#ifndef PNG_INTEL_SSE_OPT
-#   ifdef PNG_INTEL_SSE
-      /* Only check for SSE if the build configuration has been modified to
-       * enable SSE optimizations.  This means that these optimizations will
-       * be off by default.  See contrib/intel for more details.
-       */
-#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
-       defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-#         define PNG_INTEL_SSE_OPT 1
-#      endif
-#   endif
-#endif
-
-#if PNG_INTEL_SSE_OPT > 0
-#   ifndef PNG_INTEL_SSE_IMPLEMENTATION
-#      if defined(__SSE4_1__) || defined(__AVX__)
-          /* We are not actually using AVX, but checking for AVX is the best
-             way we can detect SSE4.1 and SSSE3 on MSVC.
-          */
-#         define PNG_INTEL_SSE_IMPLEMENTATION 3
-#      elif defined(__SSSE3__)
-#         define PNG_INTEL_SSE_IMPLEMENTATION 2
-#      elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-#         define PNG_INTEL_SSE_IMPLEMENTATION 1
-#      else
-#         define PNG_INTEL_SSE_IMPLEMENTATION 0
-#      endif
-#   endif
-
-#   if PNG_INTEL_SSE_IMPLEMENTATION > 0
-#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
-#   endif
-#endif
-
------------------cut----------------
-
-4. Add the following lines to pngpriv.h, following the prototype for
-png_read_filter_row_paeth4_neon:
-
------------------cut----------------
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-
------------------cut----------------

contrib/intel/intel_sse.patch

-diff --git a/configure.ac b/configure.ac
---- a/configure.ac	2016-08-29 11:46:27.000000000 -0400
-+++ b/configure.ac	2016-08-29 16:57:03.866355018 -0400
-@@ -386,16 +386,51 @@ AC_ARG_ENABLE([mips-msa],
- # future host CPU does not match 'mips*')
- 
- AM_CONDITIONAL([PNG_MIPS_MSA],
-    [test "$enable_mips_msa" != 'no' &&
-     case "$host_cpu" in
-       mipsel*|mips64el*) :;;
-     esac])
- 
-+# INTEL
-+# =====
-+#
-+# INTEL SSE (SIMD) support.
-+
-+AC_ARG_ENABLE([intel-sse],
-+   AS_HELP_STRING([[[--enable-intel-sse]]],
-+      [Enable Intel SSE optimizations: =no/off, yes/on:]
-+      [no/off: disable the optimizations;]
-+      [yes/on: enable the optimizations.]
-+      [If not specified: determined by the compiler.]),
-+   [case "$enableval" in
-+      no|off)
-+         # disable the default enabling:
-+         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-+                   [Disable Intel SSE optimizations])
-+         # Prevent inclusion of the assembler files below:
-+         enable_intel_sse=no;;
-+      yes|on)
-+         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-+                   [Enable Intel SSE optimizations]);;
-+      *)
-+         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
-+   esac])
-+
-+# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-+# or where Intel optimizations were explicitly requested (this allows a
-+# fallback if a future host CPU does not match 'x86*')
-+AM_CONDITIONAL([PNG_INTEL_SSE],
-+   [test "$enable_intel_sse" != 'no' &&
-+    case "$host_cpu" in
-+      i?86|x86_64) :;;
-+      *)    test "$enable_intel_sse" != '';;
-+    esac])
-+
- AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
- 
- # Config files, substituting as above
- AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
- AC_CONFIG_FILES([libpng-config:libpng-config.in],
-    [chmod +x libpng-config])
- 
- AC_OUTPUT
-diff --git a/Makefile.am b/Makefile.am
---- a/Makefile.am	2016-08-29 11:46:27.000000000 -0400
-+++ b/Makefile.am	2016-08-29 16:57:45.955528215 -0400
-@@ -97,16 +97,21 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SO
- 	arm/filter_neon.S arm/filter_neon_intrinsics.c
- endif
- 
- if PNG_MIPS_MSA
- libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/mips_init.c\
- 	mips/filter_msa_intrinsics.c
- endif
- 
-+if PNG_INTEL_SSE
-+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += contrib/intel/intel_init.c\
-+    contrib/intel/filter_sse2_intrinsics.c
-+endif
-+
- nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
- 
- libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
- 	-version-number @PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0
- 
- if HAVE_LD_VERSION_SCRIPT
- #   Versioned symbols and restricted exports
- if HAVE_SOLARIS_LD
-diff --git a/pngpriv.h b/pngpriv.h
---- debug16/pngpriv.h	2016-08-30 10:46:36.000000000 -0400
-+++ libpng16/pngpriv.h	2016-08-30 11:57:25.672280202 -0400
-@@ -185,16 +185,52 @@
- #ifndef PNG_MIPS_MSA_OPT
- #  if defined(__mips_msa) && (__mips_isa_rev >= 5) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
- #     define PNG_MIPS_MSA_OPT 2
- #  else
- #     define PNG_MIPS_MSA_OPT 0
- #  endif
- #endif
- 
-+#ifndef PNG_INTEL_SSE_OPT
-+#   ifdef PNG_INTEL_SSE
-+      /* Only check for SSE if the build configuration has been modified to
-+       * enable SSE optimizations.  This means that these optimizations will
-+       * be off by default.  See contrib/intel for more details.
-+       */
-+#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
-+       defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-+#         define PNG_INTEL_SSE_OPT 1
-+#      endif
-+#   endif
-+#endif
-+
-+#if PNG_INTEL_SSE_OPT > 0
-+#   ifndef PNG_INTEL_SSE_IMPLEMENTATION
-+#      if defined(__SSE4_1__) || defined(__AVX__)
-+          /* We are not actually using AVX, but checking for AVX is the best
-+             way we can detect SSE4.1 and SSSE3 on MSVC.
-+          */
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 3
-+#      elif defined(__SSSE3__)
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 2
-+#      elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
-+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 1
-+#      else
-+#         define PNG_INTEL_SSE_IMPLEMENTATION 0
-+#      endif
-+#   endif
-+
-+#   if PNG_INTEL_SSE_IMPLEMENTATION > 0
-+#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
-+#   endif
-+#endif
-+
- #if PNG_MIPS_MSA_OPT > 0
- #  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_msa
- #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
- #     if defined(__mips_msa)
- #        if defined(__clang__)
- #        elif defined(__GNUC__)
- #           if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
- #              define PNG_MIPS_MSA_IMPLEMENTATION 2
-@@ -1251,16 +1287,31 @@ PNG_INTERNAL_FUNCTION(void,png_read_filt
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_msa,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_msa,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_msa,(png_row_infop
-     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
- #endif
- 
-+#if PNG_INTEL_SSE_IMPLEMENTATION > 0
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
-+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-+#endif
-+
- /* Choose the best filter to use and filter the row data */
- PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
-     png_row_infop row_info),PNG_EMPTY);
- 
- #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
- PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
-    png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
-    /* Read 'avail_out' bytes of data from the IDAT stream.  If the output buffer
-@@ -1986,16 +2037,21 @@ PNG_INTERNAL_FUNCTION(void, PNG_FILTER_O
- PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
-    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
- #endif
- 
- #if PNG_MIPS_MSA_OPT > 0
- PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_msa,
-    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
- #endif
-+
-+#  if PNG_INTEL_SSE_IMPLEMENTATION > 0
-+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
-+   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
-+#  endif
- #endif
- 
- PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
-    png_const_charp key, png_bytep new_key), PNG_EMPTY);
- 
- /* Maintainer: Put new private prototypes here ^ */
- 
- #include "pngdebug.h"

contrib/intel/filter_sse2_intrinsics.c → intel/filter_sse2_intrinsics.c

 
 /* filter_sse2_intrinsics.c - SSE2 optimized filter functions
  *
- * Copyright (c) 2016 Google, Inc.
+ * Copyright (c) 2016-2017 Glenn Randers-Pehrson
  * Written by Mike Klein and Matt Sarett
- * Derived from arm/filter_neon_intrinsics.c, which was
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
+ * Derived from arm/filter_neon_intrinsics.c
  *
- * Last changed in libpng 1.6.24 [August 4, 2016]
+ * Last changed in libpng 1.6.29 [(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"
+#include "../pngpriv.h"
 
 #ifdef PNG_READ_SUPPORTED
 

contrib/intel/intel_init.c → intel/intel_init.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
+ * Copyright (c) 2016-2017 Glenn Randers-Pehrson
+ * Written by Mike Klein and Matt Sarett, Google, Inc.
+ * Derived from arm/arm_init.c
  *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.29 [(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"
+#include "../pngpriv.h"
 
 #ifdef PNG_READ_SUPPORTED
 #if PNG_INTEL_SSE_IMPLEMENTATION > 0

png.h

 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.29beta01, January 5, 2017
+ * libpng version 1.6.29beta01, January 6, 2017
  *
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.29beta01, January 5, 2017:
+ *   libpng versions 0.97, January 1998, through 1.6.29beta01, January 6, 2017:
  *     Glenn Randers-Pehrson.
  *   See also "Contributing Authors", below.
  */
@@ -25,7 +25,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.0.7, July 1, 2000 through 1.6.29beta01, January 5, 2017 are
+ * libpng versions 1.0.7, July 1, 2000 through 1.6.29beta01, January 6, 2017 are
  * Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, and are distributed according to the same
  * disclaimer and license as libpng-1.0.6 with the following individuals
@@ -38,6 +38,7 @@
  *    Gilles Vollant
  *    James Yu
  *    Mandar Sahastrabuddhe
+ *    Google Inc.
  *
  * and with the following additions to the disclaimer:
  *
@@ -239,7 +240,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    January 5, 2017
+ *    January 6, 2017
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -308,7 +309,7 @@
 
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.6.29beta01"
-#define PNG_HEADER_VERSION_STRING " libpng version 1.6.29beta01 - January 5, 2017\n"
+#define PNG_HEADER_VERSION_STRING " libpng version 1.6.29beta01 - January 6, 2017\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16

pngpriv.h

@@ -190,6 +190,42 @@
 #  endif
 #endif
 
+#ifndef PNG_INTEL_SSE_OPT
+#   ifdef PNG_INTEL_SSE
+      /* Only check for SSE if the build configuration has been modified to
+       * enable SSE optimizations.  This means that these optimizations will
+       * be off by default.  See contrib/intel for more details.
+       */
+#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
+       defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
+#         define PNG_INTEL_SSE_OPT 1
+#      endif
+#   endif
+#endif
+
+#if PNG_INTEL_SSE_OPT > 0
+#   ifndef PNG_INTEL_SSE_IMPLEMENTATION
+#      if defined(__SSE4_1__) || defined(__AVX__)
+          /* We are not actually using AVX, but checking for AVX is the best
+             way we can detect SSE4.1 and SSSE3 on MSVC.
+          */
+#         define PNG_INTEL_SSE_IMPLEMENTATION 3
+#      elif defined(__SSSE3__)
+#         define PNG_INTEL_SSE_IMPLEMENTATION 2
+#      elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
+       (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
+#         define PNG_INTEL_SSE_IMPLEMENTATION 1
+#      else
+#         define PNG_INTEL_SSE_IMPLEMENTATION 0
+#      endif
+#   endif
+
+#   if PNG_INTEL_SSE_IMPLEMENTATION > 0
+#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
+#   endif
+#endif
+
 #if PNG_MIPS_MSA_OPT > 0
 #  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_msa
 #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
@@ -1256,6 +1292,21 @@ PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_msa,(png_row_infop
     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
 #endif
 
+#if PNG_INTEL_SSE_IMPLEMENTATION > 0
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+#endif
+
 /* Choose the best filter to use and filter the row data */
 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
     png_row_infop row_info),PNG_EMPTY);
@@ -1991,6 +2042,11 @@ PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_msa,
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
+
+#  if PNG_INTEL_SSE_IMPLEMENTATION > 0
+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
+   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
+#  endif
 #endif
 
 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,