If __riscv_hwprobe() fails, then the kernel version is presumably too
old. There is not much point falling back to the auxillary vector.
- The Linux kernel requires I, so the flag is always set on Linux, and
run-time detection is unnecessary. Our RISC-V assembler does anyway not
support targets without I.
- Linux can compile with or without F and D, but it cannot perform
run-time detection for them (a kernel with F support will not boot a
processor without F). The run-time detection is thus useless in that
case. Besides F and D extensions are used throughout the C code, so
their run-time detection would not be practical.
- Support for V was added in a later kernel version than riscv_hwprobe(),
so the system call will always be available if the kernel supports V.
The only exception would be vendor kernel forks, but those are known to
haphasardly pretend to support V on systems without actual V support, or
with only pre-ratification binary-incompatible version. Furthermore, a
large chunk of our optimisations require Zba and/or Zbb which cannot be
detected with HWCAP in those kernels.
For what it is worth, OpenJDK already took a similar action. Note that this
keeps AT_HWCAP usage for platforms with neither C run-time <sys/hwprobe.h>
nor kernel <asm/hwprobe.h>, notably kernels other than Linux.
This reuses the DC bypass functions from the multiple IDCT functions, to
leverage vector code.
As an added bonus, the caller functions can now rely on the callee functions
to preserve their parameters, thus cutting down on stack spills.
No functional changes. This just moves the assembler so that it can be
referenced by other functions in h264idct_rvv.S with local jumps.
Edited-by: Rémi Denis-Courmont <remi@remlab.net>
Fixes: CID1604383 Unchecked return value
Fixes: CID1604439 Unchecked return value
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: CID1604487 Unchecked return value
Fixes: CID1604494 Unchecked return value
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
not sure this is possible
Fixes: CID1604446 Overflowed constant
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
We assign a 64bit variable to it before checking
Fixes: CID1604544 Overflowed integer argument
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
We subtract 24 so it must be at least 24
Fixes: CID1604482 Overflowed constant
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Found by reviewing CID1513722 Operands don't affect result
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: CID1604398 Unchecked return value
Fixes: CID1604542 Unchecked return value
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: CID1452758 Out-of-bounds read (actual out of bounds access depends on a frame with more than 3 planes)
Sponsored-by: Sovereign Tech Fund
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: index -2 out of bounds for type 'const enum AVCodecID [3]'
Fixes: 69866/clusterfuzz-testcase-minimized-ffmpeg_dem_IAMF_fuzzer-4971166119821312
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: signed integer overflow: -1082982400 + -1068681048 cannot be represented in type 'int'
Fixes: 69995/clusterfuzz-testcase-minimized-ffmpeg_SWS_fuzzer-6285740271534080
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: signed integer overflow: 9223372036854775807 - -1 cannot be represented in type 'long'
Fixes: 68578/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer-6032171648221184
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
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: 68550/clusterfuzz-testcase-minimized-ffmpeg_dem_MXF_fuzzer-6424065930756096
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>