media/libpng/arm/arm_init.c@97036ab72558 (annotated)
media/libpng/arm/arm_init.c
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
| michael@0 | 1 | |
| michael@0 | 2 | /* arm_init.c - NEON optimised filter functions |
| michael@0 | 3 | * |
| michael@0 | 4 | * Copyright (c) 2014 Glenn Randers-Pehrson |
| michael@0 | 5 | * Written by Mans Rullgard, 2011. |
| michael@0 | 6 | * Last changed in libpng 1.6.10 [March 6, 2014] |
| michael@0 | 7 | * |
| michael@0 | 8 | * This code is released under the libpng license. |
| michael@0 | 9 | * For conditions of distribution and use, see the disclaimer |
| michael@0 | 10 | * and license in png.h |
| michael@0 | 11 | */ |
| michael@0 | 12 | /* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are |
| michael@0 | 13 | * called. |
| michael@0 | 14 | */ |
| michael@0 | 15 | #define _POSIX_SOURCE 1 |
| michael@0 | 16 | |
| michael@0 | 17 | #include "../pngpriv.h" |
| michael@0 | 18 | |
| michael@0 | 19 | #ifdef PNG_READ_SUPPORTED |
| michael@0 | 20 | #if PNG_ARM_NEON_OPT > 0 |
| michael@0 | 21 | #ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */ |
| michael@0 | 22 | /* WARNING: it is strongly recommended that you do not build libpng with |
| michael@0 | 23 | * run-time checks for CPU features if at all possible. In the case of the ARM |
| michael@0 | 24 | * NEON instructions there is no processor-specific way of detecting the |
| michael@0 | 25 | * presense of the required support, therefore run-time detectioon is extremely |
| michael@0 | 26 | * OS specific. |
| michael@0 | 27 | * |
| michael@0 | 28 | * You may set the macro PNG_ARM_NEON_FILE to the file name of file containing |
| michael@0 | 29 | * a fragment of C source code which defines the png_have_neon function. There |
| michael@0 | 30 | * are a number of implementations in contrib/arm-neon, but the only one that |
| michael@0 | 31 | * has partial support is contrib/arm-neon/linux.c - a generic Linux |
| michael@0 | 32 | * implementation which reads /proc/cpufino. |
| michael@0 | 33 | */ |
| michael@0 | 34 | #ifndef PNG_ARM_NEON_FILE |
| michael@0 | 35 | # ifdef __linux__ |
| michael@0 | 36 | # define PNG_ARM_NEON_FILE "linux.c" |
| michael@0 | 37 | # endif |
| michael@0 | 38 | #endif |
| michael@0 | 39 | |
| michael@0 | 40 | #ifdef PNG_ARM_NEON_FILE |
| michael@0 | 41 | |
| michael@0 | 42 | #include <signal.h> /* for sig_atomic_t */ |
| michael@0 | 43 | static int png_have_neon(png_structp png_ptr); |
| michael@0 | 44 | #include PNG_ARM_NEON_FILE |
| michael@0 | 45 | |
| michael@0 | 46 | #else /* PNG_ARM_NEON_FILE */ |
| michael@0 | 47 | # error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks" |
| michael@0 | 48 | #endif /* PNG_ARM_NEON_FILE */ |
| michael@0 | 49 | #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */ |
| michael@0 | 50 | |
| michael@0 | 51 | #ifndef PNG_ALIGNED_MEMORY_SUPPORTED |
| michael@0 | 52 | # error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED" |
| michael@0 | 53 | #endif |
| michael@0 | 54 | |
| michael@0 | 55 | void |
| michael@0 | 56 | png_init_filter_functions_neon(png_structp pp, unsigned int bpp) |
| michael@0 | 57 | { |
| michael@0 | 58 | /* The switch statement is compiled in for ARM_NEON_API, the call to |
| michael@0 | 59 | * png_have_neon is compiled in for ARM_NEON_CHECK. If both are defined |
| michael@0 | 60 | * the check is only performed if the API has not set the NEON option on |
| michael@0 | 61 | * or off explicitly. In this case the check controls what happens. |
| michael@0 | 62 | * |
| michael@0 | 63 | * If the CHECK is not compiled in and the option is UNSET the behavior prior |
| michael@0 | 64 | * to 1.6.7 was to use the NEON code - this was a bug caused by having the |
| michael@0 | 65 | * wrong order of the 'ON' and 'default' cases. UNSET now defaults to OFF, |
| michael@0 | 66 | * as documented in png.h |
| michael@0 | 67 | */ |
| michael@0 | 68 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
| michael@0 | 69 | switch ((pp->options >> PNG_ARM_NEON) & 3) |
| michael@0 | 70 | { |
| michael@0 | 71 | case PNG_OPTION_UNSET: |
| michael@0 | 72 | /* Allow the run-time check to execute if it has been enabled - |
| michael@0 | 73 | * thus both API and CHECK can be turned on. If it isn't supported |
| michael@0 | 74 | * this case will fall through to the 'default' below, which just |
| michael@0 | 75 | * returns. |
| michael@0 | 76 | */ |
| michael@0 | 77 | #endif /* PNG_ARM_NEON_API_SUPPORTED */ |
| michael@0 | 78 | #ifdef PNG_ARM_NEON_CHECK_SUPPORTED |
| michael@0 | 79 | { |
| michael@0 | 80 | static volatile sig_atomic_t no_neon = -1; /* not checked */ |
| michael@0 | 81 | |
| michael@0 | 82 | if (no_neon < 0) |
| michael@0 | 83 | no_neon = !png_have_neon(pp); |
| michael@0 | 84 | |
| michael@0 | 85 | if (no_neon) |
| michael@0 | 86 | return; |
| michael@0 | 87 | } |
| michael@0 | 88 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
| michael@0 | 89 | break; |
| michael@0 | 90 | #endif |
| michael@0 | 91 | #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */ |
| michael@0 | 92 | |
| michael@0 | 93 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
| michael@0 | 94 | default: /* OFF or INVALID */ |
| michael@0 | 95 | return; |
| michael@0 | 96 | |
| michael@0 | 97 | case PNG_OPTION_ON: |
| michael@0 | 98 | /* Option turned on */ |
| michael@0 | 99 | break; |
| michael@0 | 100 | } |
| michael@0 | 101 | #endif |
| michael@0 | 102 | |
| michael@0 | 103 | /* IMPORTANT: any new external functions used here must be declared using |
| michael@0 | 104 | * PNG_INTERNAL_FUNCTION in ../pngpriv.h. This is required so that the |
| michael@0 | 105 | * 'prefix' option to configure works: |
| michael@0 | 106 | * |
| michael@0 | 107 | * ./configure --with-libpng-prefix=foobar_ |
| michael@0 | 108 | * |
| michael@0 | 109 | * Verify you have got this right by running the above command, doing a build |
| michael@0 | 110 | * and examining pngprefix.h; it must contain a #define for every external |
| michael@0 | 111 | * function you add. (Notice that this happens automatically for the |
| michael@0 | 112 | * initialization function.) |
| michael@0 | 113 | */ |
| michael@0 | 114 | pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon; |
| michael@0 | 115 | |
| michael@0 | 116 | if (bpp == 3) |
| michael@0 | 117 | { |
| michael@0 | 118 | pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon; |
| michael@0 | 119 | pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon; |
| michael@0 | 120 | pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
| michael@0 | 121 | png_read_filter_row_paeth3_neon; |
| michael@0 | 122 | } |
| michael@0 | 123 | |
| michael@0 | 124 | else if (bpp == 4) |
| michael@0 | 125 | { |
| michael@0 | 126 | pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon; |
| michael@0 | 127 | pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon; |
| michael@0 | 128 | pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
| michael@0 | 129 | png_read_filter_row_paeth4_neon; |
| michael@0 | 130 | } |
| michael@0 | 131 | } |
| michael@0 | 132 | #endif /* PNG_ARM_NEON_OPT > 0 */ |
| michael@0 | 133 | #endif /* PNG_READ_SUPPORTED */ |
