libavutil/common.h is a public header that provides generic math
functions whereas libavutil/intmath.h is a private header that contains
plattform-specific optimized versions of said math functions. common.h
includes intmath.h (when building the FFmpeg libraries) so that the
optimized versions are used for them.
This interdependency sometimes causes trouble: intmath.h once contained
an inlined ff_sqrt function that relied upon av_log2_16bit. In case there
was no optimized logarithm available on this plattform, intmath.h needed
to include common.h to get the generic implementation and this has been
done after the optimized versions (if any) have been provided so that
common.h used the optimized versions; it also needed to be done before
ff_sqrt. Yet when intmath.h was included from common.h and if an ordinary
inclusion guard was used by common.h, the #include "common.h" in intmath.h
was a no-op and therefore av_log2_16bit was still unknown at the end of
intmath.h (and also in ff_sqrt) if no optimized version was available.
Before a955b59658 this was solved by
duplicating the #ifndef av_log2_16bit check after the inclusion of
common.h in intmath.h; said commit instead moved these checks to the
end of common.h, outside the inclusion guards and made common.h include
itself to get these unguarded defines. This is still the current
state of affairs.
Yet this is unnecessary since 9734b8ba56
as said commit removed ff_sqrt as well as the #include "common.h" from
intmath.h. Therefore this commit moves everything inside the inclusion
guards and makes common.h not include itself.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
No benchmark because this is not used in any speed relevant pathes nor is it
used where __builtin_add_overflow is available.
So I do not know how to realistically benchmark it.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: left shift of 1913647649 by 1 places cannot be represented in type 'int'
Fixes: 23572/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMALOSSLESS_fuzzer-5082619795734528
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Many places are using their own custom code for handling overflow
around timestamps or other int64_t values. There are enough of these
now that having some common saturated math functions seems sound.
Signed-off-by: Dale Curtis <dalecurtis@chromium.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
When used ROUNDED_DIV(a,b), if a is unsigned integer zero, it's
will lead to an underflow issue(it called unsigned integer
wrapping).
Fixes#8062
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Mengye Lv <mengyelv@tencent.com>
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
av_mod_uintp2_c uses a bitwise AND with (1 << p) - 1 to clear the high
bits of an unsigned int. But this is undefined if p == 31, because 1 is
an int and 2^31 is not representable in an int. So make 1 unsigned.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: negation of -2147483648 cannot be represented in type 'int'; cast to an unsigned type to negate this value to itself
Fixes: 8521/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DIRAC_fuzzer-5639024952737792
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: 5567/clusterfuzz-testcase-minimized-5769966247739392
Fixes: runtime error: negation of -2147483648 cannot be represented in type 'int'; cast to an unsigned type to negate this value to itself
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Add av_sat_sub32 and av_sat_dsub32 as the subtraction analogues to
av_sat_add32/av_sat_dadd32.
Also clarify the formulas for dadd32/dsub32.
Signed-off-by: Andrew D'Addesio <modchipv12@gmail.com>
Libav, for some reason, merged this as a public API function. This will
aid in future merges.
A define is left for backwards compat, just in case some person
used it, since it is in a public header.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
This fixes ubsan runtime error: signed integer overflow: 8388608 +
2140274688 cannot be represented in type 'int'
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
* commit '50078c1c8070dd8d1c329e8117ff30ec72489039':
libavutil: move FFALIGN macro from common.h to macros.h
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>
Include macros.h explicitly in common.h so that external code using
FFALIGN does not break. It was already implicitly included through
version.h. Include macros.h in lls.h and internal.h for FFALIGN.
lls.h was including common.h only for FFALIGN and internal.h was
missing the include for FFALIGN. `make checkheaders` did not catch it
because it's an internal header.
The function is renamed to ff_rint64_clip()
This should avoid build failures on VS2012
Feel free to changes this to a different solution
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The rationale for this function is reflected in the documentation for
it, and is copied here:
Clip a double value into the long long amin-amax range.
This function is needed because conversion of floating point to integers when
it does not fit in the integer's representation does not necessarily saturate
correctly (usually converted to a cvttsd2si on x86) which saturates numbers
> INT64_MAX to INT64_MIN. The standard marks such conversions as undefined
behavior, allowing this sort of mathematically bogus conversions. This provides
a safe alternative that is slower obviously but assures safety and better
mathematical behavior.
API:
@param a value to clip
@param amin minimum value of the clip range
@param amax maximum value of the clip range
@return clipped value
Note that a priori if one can guarantee from the calling side that the
double is in range, it is safe to simply do an explicit/implicit cast,
and that will be far faster. However, otherwise this function should be
used.
avutil minor version is bumped.
Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This is of use for defining comparator callbacks. Common approaches like
return x-y are not safe due to the risks of overflow.
Furthermore, the (x > y) - (x < y) trick is optimized to branchless
code.
This also documents this macro accordingly.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This macro avoids the undefined corner case with the *_MIN values
Previous version Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
there already is a function, av_clip_uintp2() that clips a signed integer
to an unsigned power-of-two range, i.e. 0,2^p-1
this patch adds a function av_clip_intp2() that clips a signed integer
to a signed power-of-two range, i.e. -(2^p),(2^p-1)
the new function can be used as a special case for av_clip(), e.g.
av_clip(x, -8192, 8191) can be rewritten as av_clip_intp2(x, 13)
there are ARM instructions, usat and ssat resp., which map nicely to these
functions (see next patch)
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
programs using ffmpeg that are compiled with -Wshorten-64-to-32
gives a warning when using header files common.h and rational.h
cast 64-bit truncated values to (uint32_t) to avoid the warning
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
As far as I can tell the code should not change behaviour
depending on locale in any of these places.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
* commit '3b4296f41473a5b39e84d7a49d480624c9c60040':
avformat: clarify stream id for muxing
fate: Add dependencies for aac, alac, amrnb, amrwb, atrac tests
ppc: do not pass redundant compiler flags
avutil: change GET_UTF8 to not use av_log2()
segment: fix NULL pointer dereference in seg_write_header()
Conflicts:
tests/fate/aac.mak
Merged-by: Michael Niedermayer <michaelni@gmx.at>
