README_MOZILLA (2822B)
1 This directory contains build files for dav1d. The actual library 2 source is in $TOPSRCDIR/third_party/dav1d/ 3 4 Any patches or additional configuration to be applied to the 5 upstream source should be kept here in the media/libdav1d 6 directory. 7 8 To update the library source and build config files, execute 9 10 ./mach vendor media/libdav1d/moz.yaml 11 12 To update to a specific upstream git tag or commit, use 13 14 ./mach vendor media/libdav1d/moz.yaml -r <commit> 15 16 The upstream git repository is https://code.videolan.org/videolan/dav1d 17 18 To update to a fork, use 19 20 ./mach vendor media/libdav1d/moz.yaml --repo <repository url> [-r <commit>] 21 22 23 The rough steps are: 24 - Execute ./mach vendor media/libdav1d/moz.yaml -r {tag-name} # ex: ./mach vendor media/libdav1d/moz.yaml -r 0.6.0 25 - Update ./moz.build and ./asm/moz.build to add new files and remove deleted ones using 26 third_party/dav1d/src/meson.build as a guide (confirm with the diff) (note the 27 empty .asm file in x86_64) 28 - Some assembly files (notably avx2-specific ones) will generate no code on win32 builds, 29 leading to a nasm failure like: 30 "panic: assertion cv8_state.source_files != NULL failed at output/codeview.c:517" 31 These files can be identified by the `%if ARCH_X86_64` conditional around the entire contents. 32 To work around this error, move the sources to the moz.build block with the 33 `if CONFIG['TARGET_CPU'] == 'x86_64'` conditional. 34 See https://bugzilla.mozilla.org/show_bug.cgi?id=1712832 and 35 https://bugzilla.nasm.us/show_bug.cgi?id=3392658 36 - Some files will be automatically added to the various autovendored_sources.mozbuild files. 37 In the case of the asm dir, these may cause build failures on particular platforms which 38 can be resolved by moving those out of autovendored_sources.mozbuild and into the regular 39 moz.build which has a condition on CONFIG['TARGET_CPU']. 40 - Files ending in _tmpl.c may be automatically added to SOURCES, resulting in build failures. 41 To fix this, the file must be moved to the appropriate bitdepth_basenames list where 42 generate_source.py will generate the templates into buildable source files. In general, 43 all *_tmpl.c files require BITDEPTH to be defined. 44 - Clone the tag from the dav1d repo and build a stand-alone libdav1d following the steps here: 45 https://code.videolan.org/videolan/dav1d#compile 46 - Copy vcs_version.h from the local build/include/vcs_version.h 47 to media/libdav1d/vcs_version.h 48 - Copy version.h from local build/include/dav1d/version.h to 49 media/libdav1d/version.h 50 - Add new options, if any, in moz.build or config.h 51 52 Tips: 53 - If you see build failures in build-linux64-base-toolchains (or 54 similar jobs) dav1d may now require a higher minimum nasm version 55 than our base toolchains currently support. A bug updating the 56 minimum nasm version will probably be necessary.