1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libpng/arm/arm_init.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,133 @@
1.4 +
1.5 +/* arm_init.c - NEON optimised filter functions
1.6 + *
1.7 + * Copyright (c) 2014 Glenn Randers-Pehrson
1.8 + * Written by Mans Rullgard, 2011.
1.9 + * Last changed in libpng 1.6.10 [March 6, 2014]
1.10 + *
1.11 + * This code is released under the libpng license.
1.12 + * For conditions of distribution and use, see the disclaimer
1.13 + * and license in png.h
1.14 + */
1.15 +/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
1.16 + * called.
1.17 + */
1.18 +#define _POSIX_SOURCE 1
1.19 +
1.20 +#include "../pngpriv.h"
1.21 +
1.22 +#ifdef PNG_READ_SUPPORTED
1.23 +#if PNG_ARM_NEON_OPT > 0
1.24 +#ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
1.25 +/* WARNING: it is strongly recommended that you do not build libpng with
1.26 + * run-time checks for CPU features if at all possible. In the case of the ARM
1.27 + * NEON instructions there is no processor-specific way of detecting the
1.28 + * presense of the required support, therefore run-time detectioon is extremely
1.29 + * OS specific.
1.30 + *
1.31 + * You may set the macro PNG_ARM_NEON_FILE to the file name of file containing
1.32 + * a fragment of C source code which defines the png_have_neon function. There
1.33 + * are a number of implementations in contrib/arm-neon, but the only one that
1.34 + * has partial support is contrib/arm-neon/linux.c - a generic Linux
1.35 + * implementation which reads /proc/cpufino.
1.36 + */
1.37 +#ifndef PNG_ARM_NEON_FILE
1.38 +# ifdef __linux__
1.39 +# define PNG_ARM_NEON_FILE "linux.c"
1.40 +# endif
1.41 +#endif
1.42 +
1.43 +#ifdef PNG_ARM_NEON_FILE
1.44 +
1.45 +#include <signal.h> /* for sig_atomic_t */
1.46 +static int png_have_neon(png_structp png_ptr);
1.47 +#include PNG_ARM_NEON_FILE
1.48 +
1.49 +#else /* PNG_ARM_NEON_FILE */
1.50 +# error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
1.51 +#endif /* PNG_ARM_NEON_FILE */
1.52 +#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
1.53 +
1.54 +#ifndef PNG_ALIGNED_MEMORY_SUPPORTED
1.55 +# error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
1.56 +#endif
1.57 +
1.58 +void
1.59 +png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
1.60 +{
1.61 + /* The switch statement is compiled in for ARM_NEON_API, the call to
1.62 + * png_have_neon is compiled in for ARM_NEON_CHECK. If both are defined
1.63 + * the check is only performed if the API has not set the NEON option on
1.64 + * or off explicitly. In this case the check controls what happens.
1.65 + *
1.66 + * If the CHECK is not compiled in and the option is UNSET the behavior prior
1.67 + * to 1.6.7 was to use the NEON code - this was a bug caused by having the
1.68 + * wrong order of the 'ON' and 'default' cases. UNSET now defaults to OFF,
1.69 + * as documented in png.h
1.70 + */
1.71 +#ifdef PNG_ARM_NEON_API_SUPPORTED
1.72 + switch ((pp->options >> PNG_ARM_NEON) & 3)
1.73 + {
1.74 + case PNG_OPTION_UNSET:
1.75 + /* Allow the run-time check to execute if it has been enabled -
1.76 + * thus both API and CHECK can be turned on. If it isn't supported
1.77 + * this case will fall through to the 'default' below, which just
1.78 + * returns.
1.79 + */
1.80 +#endif /* PNG_ARM_NEON_API_SUPPORTED */
1.81 +#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
1.82 + {
1.83 + static volatile sig_atomic_t no_neon = -1; /* not checked */
1.84 +
1.85 + if (no_neon < 0)
1.86 + no_neon = !png_have_neon(pp);
1.87 +
1.88 + if (no_neon)
1.89 + return;
1.90 + }
1.91 +#ifdef PNG_ARM_NEON_API_SUPPORTED
1.92 + break;
1.93 +#endif
1.94 +#endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
1.95 +
1.96 +#ifdef PNG_ARM_NEON_API_SUPPORTED
1.97 + default: /* OFF or INVALID */
1.98 + return;
1.99 +
1.100 + case PNG_OPTION_ON:
1.101 + /* Option turned on */
1.102 + break;
1.103 + }
1.104 +#endif
1.105 +
1.106 + /* IMPORTANT: any new external functions used here must be declared using
1.107 + * PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the
1.108 + * 'prefix' option to configure works:
1.109 + *
1.110 + * ./configure --with-libpng-prefix=foobar_
1.111 + *
1.112 + * Verify you have got this right by running the above command, doing a build
1.113 + * and examining pngprefix.h; it must contain a #define for every external
1.114 + * function you add. (Notice that this happens automatically for the
1.115 + * initialization function.)
1.116 + */
1.117 + pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon;
1.118 +
1.119 + if (bpp == 3)
1.120 + {
1.121 + pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
1.122 + pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
1.123 + pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
1.124 + png_read_filter_row_paeth3_neon;
1.125 + }
1.126 +
1.127 + else if (bpp == 4)
1.128 + {
1.129 + pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon;
1.130 + pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon;
1.131 + pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
1.132 + png_read_filter_row_paeth4_neon;
1.133 + }
1.134 +}
1.135 +#endif /* PNG_ARM_NEON_OPT > 0 */
1.136 +#endif /* PNG_READ_SUPPORTED */
