2 /* mips_init.c - MSA optimised filter functions
4 * Copyright (c) 2018 Cosmin Truta
5 * Copyright (c) 2016 Glenn Randers-Pehrson
6 * Written by Mandar Sahastrabuddhe, 2016.
8 * This code is released under the libpng license.
9 * For conditions of distribution and use, see the disclaimer
10 * and license in png.h
13 /* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
16 #define _POSIX_SOURCE 1
19 #include "../pngpriv.h"
21 #ifdef PNG_READ_SUPPORTED
23 #if PNG_MIPS_MSA_OPT > 0
24 #ifdef PNG_MIPS_MSA_CHECK_SUPPORTED /* Do run-time checks */
25 /* WARNING: it is strongly recommended that you do not build libpng with
26 * run-time checks for CPU features if at all possible. In the case of the MIPS
27 * MSA instructions there is no processor-specific way of detecting the
28 * presence of the required support, therefore run-time detection is extremely
31 * You may set the macro PNG_MIPS_MSA_FILE to the file name of file containing
32 * a fragment of C source code which defines the png_have_msa function. There
33 * are a number of implementations in contrib/mips-msa, but the only one that
34 * has partial support is contrib/mips-msa/linux.c - a generic Linux
35 * implementation which reads /proc/cpufino.
37 #ifndef PNG_MIPS_MSA_FILE
39 # define PNG_MIPS_MSA_FILE "contrib/mips-msa/linux.c"
43 #ifdef PNG_MIPS_MSA_FILE
45 #include <signal.h> /* for sig_atomic_t */
46 static int png_have_msa(png_structp png_ptr);
47 #include PNG_MIPS_MSA_FILE
49 #else /* PNG_MIPS_MSA_FILE */
50 # error "PNG_MIPS_MSA_FILE undefined: no support for run-time MIPS MSA checks"
51 #endif /* PNG_MIPS_MSA_FILE */
52 #endif /* PNG_MIPS_MSA_CHECK_SUPPORTED */
54 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
55 # error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
59 png_init_filter_functions_msa(png_structp pp, unsigned int bpp)
61 /* The switch statement is compiled in for MIPS_MSA_API, the call to
62 * png_have_msa is compiled in for MIPS_MSA_CHECK. If both are defined
63 * the check is only performed if the API has not set the MSA option on
64 * or off explicitly. In this case the check controls what happens.
67 #ifdef PNG_MIPS_MSA_API_SUPPORTED
68 switch ((pp->options >> PNG_MIPS_MSA) & 3)
70 case PNG_OPTION_UNSET:
71 /* Allow the run-time check to execute if it has been enabled -
72 * thus both API and CHECK can be turned on. If it isn't supported
73 * this case will fall through to the 'default' below, which just
76 #endif /* PNG_MIPS_MSA_API_SUPPORTED */
77 #ifdef PNG_MIPS_MSA_CHECK_SUPPORTED
79 static volatile sig_atomic_t no_msa = -1; /* not checked */
82 no_msa = !png_have_msa(pp);
87 #ifdef PNG_MIPS_MSA_API_SUPPORTED
90 #endif /* PNG_MIPS_MSA_CHECK_SUPPORTED */
92 #ifdef PNG_MIPS_MSA_API_SUPPORTED
93 default: /* OFF or INVALID */
97 /* Option turned on */
102 /* IMPORTANT: any new external functions used here must be declared using
103 * PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the
104 * 'prefix' option to configure works:
106 * ./configure --with-libpng-prefix=foobar_
108 * Verify you have got this right by running the above command, doing a build
109 * and examining pngprefix.h; it must contain a #define for every external
110 * function you add. (Notice that this happens automatically for the
111 * initialization function.)
113 pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_msa;
117 pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_msa;
118 pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_msa;
119 pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth3_msa;
124 pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_msa;
125 pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_msa;
126 pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_msa;
129 #endif /* PNG_MIPS_MSA_OPT > 0 */