| /* powerpc_init.c - POWERPC optimised filter functions |
| * |
| * Copyright (c) 2018 Cosmin Truta |
| * Copyright (c) 2017 Glenn Randers-Pehrson |
| * Written by Vadim Barkov, 2017. |
| * |
| * This code is released under the libpng license. |
| * For conditions of distribution and use, see the disclaimer |
| * and license in png.h |
| */ |
| |
| /* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are |
| * called. |
| */ |
| #define _POSIX_SOURCE 1 |
| |
| #include <stdio.h> |
| #include "../pngpriv.h" |
| |
| #ifdef PNG_READ_SUPPORTED |
| |
| #if PNG_POWERPC_VSX_OPT > 0 |
| #ifdef PNG_POWERPC_VSX_CHECK_SUPPORTED /* Do run-time checks */ |
| /* WARNING: it is strongly recommended that you do not build libpng with |
| * run-time checks for CPU features if at all possible. In the case of the PowerPC |
| * VSX instructions there is no processor-specific way of detecting the |
| * presence of the required support, therefore run-time detection is extremely |
| * OS specific. |
| * |
| * You may set the macro PNG_POWERPC_VSX_FILE to the file name of file containing |
| * a fragment of C source code which defines the png_have_vsx function. There |
| * are a number of implementations in contrib/powerpc-vsx, but the only one that |
| * has partial support is contrib/powerpc-vsx/linux.c - a generic Linux |
| * implementation which reads /proc/cpufino. |
| */ |
| #ifndef PNG_POWERPC_VSX_FILE |
| # ifdef __linux__ |
| # define PNG_POWERPC_VSX_FILE "contrib/powerpc-vsx/linux_aux.c" |
| # endif |
| #endif |
| |
| #ifdef PNG_POWERPC_VSX_FILE |
| |
| #include <signal.h> /* for sig_atomic_t */ |
| static int png_have_vsx(png_structp png_ptr); |
| #include PNG_POWERPC_VSX_FILE |
| |
| #else /* PNG_POWERPC_VSX_FILE */ |
| # error "PNG_POWERPC_VSX_FILE undefined: no support for run-time POWERPC VSX checks" |
| #endif /* PNG_POWERPC_VSX_FILE */ |
| #endif /* PNG_POWERPC_VSX_CHECK_SUPPORTED */ |
| |
| void |
| png_init_filter_functions_vsx(png_structp pp, unsigned int bpp) |
| { |
| /* The switch statement is compiled in for POWERPC_VSX_API, the call to |
| * png_have_vsx is compiled in for POWERPC_VSX_CHECK. If both are defined |
| * the check is only performed if the API has not set the PowerPC option on |
| * or off explicitly. In this case the check controls what happens. |
| */ |
| |
| #ifdef PNG_POWERPC_VSX_API_SUPPORTED |
| switch ((pp->options >> PNG_POWERPC_VSX) & 3) |
| { |
| case PNG_OPTION_UNSET: |
| /* Allow the run-time check to execute if it has been enabled - |
| * thus both API and CHECK can be turned on. If it isn't supported |
| * this case will fall through to the 'default' below, which just |
| * returns. |
| */ |
| #endif /* PNG_POWERPC_VSX_API_SUPPORTED */ |
| #ifdef PNG_POWERPC_VSX_CHECK_SUPPORTED |
| { |
| static volatile sig_atomic_t no_vsx = -1; /* not checked */ |
| |
| if (no_vsx < 0) |
| no_vsx = !png_have_vsx(pp); |
| |
| if (no_vsx) |
| return; |
| } |
| #ifdef PNG_POWERPC_VSX_API_SUPPORTED |
| break; |
| #endif |
| #endif /* PNG_POWERPC_VSX_CHECK_SUPPORTED */ |
| |
| #ifdef PNG_POWERPC_VSX_API_SUPPORTED |
| default: /* OFF or INVALID */ |
| return; |
| |
| case PNG_OPTION_ON: |
| /* Option turned on */ |
| break; |
| } |
| #endif |
| |
| /* IMPORTANT: any new internal functions used here must be declared using |
| * PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the |
| * 'prefix' option to configure works: |
| * |
| * ./configure --with-libpng-prefix=foobar_ |
| * |
| * Verify you have got this right by running the above command, doing a build |
| * and examining pngprefix.h; it must contain a #define for every external |
| * function you add. (Notice that this happens automatically for the |
| * initialization function.) |
| */ |
| pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_vsx; |
| |
| if (bpp == 3) |
| { |
| pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_vsx; |
| pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_vsx; |
| pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth3_vsx; |
| } |
| |
| else if (bpp == 4) |
| { |
| pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_vsx; |
| pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_vsx; |
| pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_vsx; |
| } |
| } |
| #endif /* PNG_POWERPC_VSX_OPT > 0 */ |
| #endif /* READ */ |