On 13 May 2014 23:34, Luca Barbato <[email protected]> wrote: > On 13/05/14 17:25, [email protected] wrote: > > From: James Yu <[email protected]> > > > > Using NEON intrinsics to support ARMv7 and ARMv8 simultaneously. > > Rewrite ARMv7 assembly to intrinsics version. > > > > Toolchain: > > armv7: gcc-linaro-arm-linux-gnueabihf-4.8-2014.01_linux > > armv8: gcc-linaro-aarch64-linux-gnu-4.8-2013.10_linux > > > > [RFC] Currently, libavcodec had a aarch64 dir includes all related > assembly > > code. However, I put this file under libavcodec/arm dir first, since this > > support ARMv7 and ARMv8 simultaneously. And RFC how could we port and > > optimize libav to aarch64. > > Is the speed difference negligible ? I recall that for arm gcc (and > clang) weren't exactly great at mapping intrinsics and that produced > less than optimal code? > > Yes, it sometimes have different performance than assembly code.
I try benchmark by using Linaro toolchain for this patch, And run below commend "avconv -i mp4_movie -an -f null EMPTY-OUTPUT" to get the fps. it doesn't have obvious different performance. > Surely it is a step in the right direction (C -> intrinsics -> faster asm). > > I wish we have smarter compilers =) > > Thanks a lot for the patch, I let Janne review it. > > Thanks :-) -- Regards, James > lu > _______________________________________________ > libav-devel mailing list > [email protected] > https://lists.libav.org/mailman/listinfo/libav-devel > _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
