This is more spec-compliant because it does not rely
on dead-code elimination by the compiler. Especially
MSVC has problems with this, as can be seen in
https://ffmpeg.org/pipermail/ffmpeg-devel/2022-May/296373.html
or
https://ffmpeg.org/pipermail/ffmpeg-devel/2022-May/297022.html
This commit does not eliminate every instance where we rely
on dead code elimination: It only tackles branching to
the initialization of arch-specific dsp code, not e.g. all
uses of CONFIG_ and HAVE_ checks. But maybe it is already
enough to compile FFmpeg with MSVC with whole-programm-optimizations
enabled (if one does not disable too many components).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The existing x86 assembly for loop filters uses the stride as a
full register without clearing/sign extending the upper half
of the registers on x86_64.
This avoids crashes if the caller would have passed nonzero bits
in the previously undefined upper 32 bits of the parameters.
Signed-off-by: Martin Storsjö <martin@martin.st>
This avoids unnecessary rebuilds of most source files if only the
list of enabled components has changed, but not the other properties
of the build, set in config.h.
Signed-off-by: Martin Storsjö <martin@martin.st>
Fixes: left shift of negative value -13
Fixes: 15260/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1_fuzzer-5702076048343040
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The overlap filter is not correct for vertical edges in frame interlaced
I and P pictures. When filtering macroblocks with different FIELDTX values,
we have to match the lines at both sides of the vertical border. In addition,
we have to use the correct rounding values, depending on the line we are
filtering.
Signed-off-by: Jerome Borsboom <jerome.borsboom@carpalis.nl>
Initialise VC1DSPContext for parser as well as for decoder.
Note, the VC-1 code doesn't actually use the function pointer yet.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Initialise VC1DSPContext for parser as well as for decoder.
Note, the VC-1 code doesn't actually use the function pointer yet.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This allows further unrolling the DSP implementation where possible.
x86 and ARM DSP modified by simply moving the multiple calls from vc1dec
to the DSP code. Decoding improvements should only occurs because of the
compiler actually able to unroll more.
Decoding time: ~8.80s -> 8.64s (ie around 2%)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
For:
ff_vc1_inv_trans_{8,4}x{8,4}_{dc_,}neon
ff_put_pixels8x8_neon
ff_put_vc1_mspel_mc{0,1,2,3}{0,1,2,3}_neon (except for 00)
Based on ARM assembly code in libavcodec/arm by Rob Clark and Mans
Rullgard.
Signed-off-by: Martin Storsjö <martin@martin.st>
This ensures that these functions are inlined into the per-position
entry points, allowing constant propagation as needed for proper
optimisation.
18% faster VC1 decoding on Cortex-A9.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Results of IDCT can by far outreach the range of ff_cropTbl[], leading
to overreads and potentially crashes.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
This reverts commit f8bed30d8b. The reason
for this is that the overlap filter, which runs after IDCT, should run
on unclamped values, and thus IDCT and put_pixels() cannot be merged if
we want to attempt to be bitexact.
Merging these functions allows merging some loops, which makes the
results (particularly after SIMD optimizations) much faster.
(cherry picked from commit f8bed30d8b)
sunyuechi
Andreas Rheinhardt
Ben Avison
Martin Storsjö
Hao Chen
Michael Niedermayer
Jerome Borsboom
Zhou Xiaoyong
Diego Biurrun
Michael Niedermayer
Christophe Gisquet
Janne Grunau
Luca Barbato
Mason Carter
Mans Rullgard
Ronald S. Bultje
Mashiat Sarker Shakkhar
Alberto Delmás