Commit Graph

16 Commits

Author SHA1 Message Date
James Almer 3b345d389b avutil/cpu: split flag checks per arch in av_cpu_max_align()
Signed-off-by: James Almer <jamrial@gmail.com>
2017-09-27 23:10:09 -03:00
Hendrik Leppkes e754c8e8ca Merge commit 'e2710e790c09e49e86baa58c6063af0097cc8cb0'
* commit 'e2710e790c09e49e86baa58c6063af0097cc8cb0':
  arm: add a cpu flag for the VFPv2 vector mode

Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>
2016-01-02 11:01:29 +01:00
Janne Grunau e2710e790c arm: add a cpu flag for the VFPv2 vector mode
The vector mode was deprecated in ARMv7-A/VFPv3 and various cpu
implementations do not support it in hardware. Vector mode code will
depending the OS either be emulated in software or result in an illegal
instruction on cpus which does not support it. This was not really
problem in practice since NEON implementations of the same functions are
preferred. It will however become a problem for checkasm which tests
every cpu flag separately.

Since this is a cpu feature newer cpu do not support anymore the
behaviour of this flag differs from the other flags. It can be only
activated by runtime cpu feature selection.
2015-12-14 16:42:35 +01:00
Andreas Cadhalpun 5bf84a584e arm: only enable setend on ARMv6
Without this check it causes SIGILL crashes on ARMv5.

Reviewed-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
2015-06-05 17:14:10 +02:00
Michael Niedermayer 1e519b9d40 avutil: turn arm setend into a cpuflag
this allows disabling and enabling it
it also prevents crashes if vfpv3 and neon are disabled which previously
would have enabled the flag

And last but not least one can enable setend on cpus like cortex-a8 where
its fast but disabled by default

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2014-08-13 14:50:15 +02:00
Michael Niedermayer 01983e50c0 Merge commit '7b0c7c9163fe3dd0081696befde28617119d2590'
* commit '7b0c7c9163fe3dd0081696befde28617119d2590':
  arm: Detect 32 bit cpu features on ARMv8 when running on a 64 bit kernel

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2014-06-28 21:31:18 +02:00
Martin Storsjö 7b0c7c9163 arm: Detect 32 bit cpu features on ARMv8 when running on a 64 bit kernel
When running on a 64 bit kernel, /proc/cpuinfo lists different
optional features than on 32 bit kernels (because some of them
are mandatory in the 64 bit implemenations).

The kernel does list the old features properly if they are queried
via /proc/self/auxv though - however this file is not always readable
(e.g. on most android systems). The getauxval function could also
provide the same info as /proc/self/auxv even if this file isn't
readable, but this function is not always available (and thus would
need to be loaded with dlsym for compatibility with older android
versions).

The android cpufeatures library does this slightly differently,
by assuming that these are available if the "CPU architecture"
line is >= 8, see [1] for details.

It has been suggested to include the old, non-optional features in
/proc/cpuinfo as well, but that suggested patch never was merged.
See [2] for the discussion around this suggestion.

[1] https://android-review.googlesource.com/91380
[2] http://marc.info/?l=linux-arm-kernel&m=139087240101974

Signed-off-by: Martin Storsjö <martin@martin.st>
2014-06-28 22:16:59 +03:00
Thilo Borgmann d814a839ac Reinstate proper FFmpeg license for all files. 2013-08-30 15:47:38 +00:00
Diego Biurrun b78b10c4b7 avutil: Move internal CPU detection function declarations to private header 2013-08-28 23:54:14 +02:00
Martin Storsjö ab8f1a6989 arm: Fall back to runtime cpu feature detection via /proc/cpuinfo
On recent android versions, /proc/self/auxw is unreadable
(unless the process is running running under the shell uid or
in debuggable mode, which makes it hard to notice). See
http://b.android.com/43055 and
https://android-review.googlesource.com/51271 for more information
about the issue.

This makes sure e.g. neon optimizations are enabled at runtime in
android apps even when built in release mode, if configured to
use the runtime detection.

CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
2013-02-11 17:15:15 +02:00
Mans Rullgard b57c1da81e arm: detect cpu features at runtime on Linux
This allows compiling optimised functions for features not enabled
in the core build and selecting these at runtime if the system has
the necessary support.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-12-07 16:54:04 +00:00
Mans Rullgard b326755989 arm: rename ARMVFP config symbol to VFP
This is consistent with usual ARM nomenclature as well as with the
VFPV3 and NEON symbols which both lack the ARM prefix.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-12-07 16:54:04 +00:00
Mans Rullgard d526c5338d ARM: allow runtime masking of CPU features
This allows masking CPU features with the -cpuflags avconv option
which is useful for testing different optimisations without rebuilding.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2012-04-22 12:30:45 +01:00
Janne Grunau 363bd1c62c remove iwmmxt optimizations
The were broken since August of 2010 without anyone noticing until
three weeks ago. Nobody cares about it anymore and hopefully Marvell
will support NEON like in the PXA978 from now on.
2012-03-12 22:46:56 +01:00
Mans Rullgard 2912e87a6c Replace FFmpeg with Libav in licence headers
Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-03-19 13:33:20 +00:00
Måns Rullgård 9275438a19 Clean up av_get_cpu_flag()
Instead of defining functions in per-arch header files included
by the main cpu.c, define them normally and call them from the
generic one.

Originally committed as revision 25084 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-09-09 18:51:45 +00:00