Clang versions before 17 (Xcode versions up to and including 15.0)
had a very annoying bug in its behaviour of the ".arch" directive
in assembly. If the directive only contained a level, such as
".arch armv8.2-a", it did validate the name of the level, but it
didn't apply the level to what instructions are allowed. The level
was applied if the directive contained an extra feature enabled,
such as ".arch armv8.2-a+crc" though. It was also applied on the
next ".arch_extension" directive.
This bug, combined with the fact that the same versions of Clang
didn't support the dotprod/i8mm extension names in either
".arch <level>+<feature>" or in ".arch_extension", could lead to
unexepcted build failures.
As the dotprod/i8mm extensions couldn't be enabled dynamically
via the ".arch_extension" directive, someone building ffmpeg could
try to enable them by configuring their build with
--extra-cflags="-march=armv8.6-a".
During configure, we test for support for the i8mm instructions
like this:
# Built with -march=armv8.6-a
.arch armv8.2-a # Has no visible effect here
#.arch_extension i8mm # Omitted as the extension name isn't known
usdot v0.4s, v0.16b, v0.16b
# Successfully assembled as armv8.6-a is the effective level,
# and i8mm is enabled implicitly in armv8.6-a.
Thus, we would enable assembling those instructions. However if
we later check for another extension, such as sve (which those
versions of Clang actually do support), we can later run into the
following situation when building actual code:
# Built with -march=armv8.6-a
.arch armv8.2-a # Has no visible effect here
#.arch_extension i8mm # Omitted as the extension name isn't known
.arch_extension sve # Included as "sve" is as supported extension name
# .arch_extension effectively activates the previous .arch directive,
# so the effective level is armv8.2-a+sve now.
usdot v0.4s, v0.16b, v0.16b
# Fails to build the instructions that require i8mm. Despite the
# configure check, the unrelated ".arch_extension sve" directive
# breaks the functionality of the i8mm feature.
This patch avoids this situation:
- By adding a dummy feature such as "+crc" on the .arch directive
(if supported), we make sure that it does get applied immediately,
avoiding it taking effect spuriously at a later unrelated
".arch_extension" directive.
- By checking for higher arch levels such as armv8.4-a and armv8.6-a,
we can assemble the dotprod and i8mm extensions without the user
needing to pass -march=armv8.6-a. This allows using the dotprod/i8mm
codepaths via runtime detection while keeping the binary runnable
on older versions. I.e. this enables the i8mm codepaths on Apple M2
machines while built with Xcode's Clang.
TL;DR: Enable the I8MM extensions for Apple M2 without the user needing
to do a custom configuration; avoid potential build breakage if a user
does such a custom configuration.
Once Xcode versions that have these issues fixed are prevalent, we
can consider reverting this change.
Signed-off-by: Martin Storsjö <martin@martin.st>
If the scan lines are aligned, we can load each row as a 64-bit value,
thus avoiding segmentation. And then we can factor the conversion or
subtraction.
In principle, the same optimisation should be possible for high depth,
but would require 128-bit elements, for which no FFmpeg CPU flag
exists.
This should hopefully clarify that the option only affects MSZ
full-width characters, and not all full-width ASCII. Additionally,
this matches the prefix with the upstream option.
Signed-off-by: TADANO Tokumei <aimingoff@pc.nifty.jp>
This patch adds two MSZ (Middle Size; half width) character
related options, mapping against newly added upstream
functionality:
* `replace_msz_japanese`, which was introduced in version 1.0.1
of libaribcaption.
* `replace_msz_glyph`, which was introduced in version 1.1.0
of libaribcaption.
The latter option improves bitmap type rendering if specified
fonts contain half-width glyphs (e.g., BIZ UDGothic), even
if both ASCII and Japanese MSZ replacement options are set
to false.
As these options require newer versions of libaribcaption, the
configure requirement has been bumped accordingly.
Signed-off-by: TADANO Tokumei <aimingoff@pc.nifty.jp>
On some environments, a `bool` variable is of smaller size than `int`.
As AV_OPT_TYPE_BOOL is internally handled as sizeof(int), if a `bool`
option was set on such an environment, the memory of following
variables would be filled. Additionally, set values may be destroyed
by av_opt_copy().
Signed-off-by: TADANO Tokumei <aimingoff@pc.nifty.jp>
av_hwframe_transfer_data try with src_ctx first. If the operation
failed with AVERROR(ENOSYS), it will try again with dst_ctx. Return
AVERROR(EINVAL) makes the second step being skipped.
Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>
Fixes a validation issue.
The issue is that the function gets called before we've sumitted a frame
for decoding to that context. However, we cannot run queries before
they've been reset, which happens at submission time.
As we'd need to otherwise run a command queue at init-time, just check
if submissions have happened.
Fixes: out of array access
Fixes: rtpdec_h264.c149/poc
Found-by: Hardik Shah of Vehere
Reviewed-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: signed integer overflow: -1028966111 + -1314089526 cannot be represented in type 'int'
Fixes: 63174/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AAC_FIXED_fuzzer-5853273711837184
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: left shift of negative value -538967841
Fixes: 62447/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEG2000_fuzzer-6427134337613824
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Tomas Härdin <git@haerdin.se>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: out of array write
Fixes: 63390/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MAGICYUV_fuzzer-5144552979431424.fuzz
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Mapping to ITU-R BS.2051-3 "Sound System J" and ITU-R BS.1196-8 "Channel
Configuration 19".
Signed-off-by: Will Wolcott <wwolcott@netflix.com>
Signed-off-by: James Almer <jamrial@gmail.com>
This layout maps to ITU-R BS.2051-3 "Sound System C" and ITU-R BS.1196-8 "Channel
Configuration 14", and it being the first layout with top layer channels, it's
best to use a different scheme to properly convey the presence and amount of said
channels.
The new name will also be a better fit for the additions in the following commits.
Signed-off-by: James Almer <jamrial@gmail.com>
Only the collocated_ref of the current frame (i.e. HEVCContext.ref)
is ever used*, so move it to HEVCContext directly after ref.
*: This goes so far that collocated_ref was not even synced across
threads in case of frame-threading.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
