[FFmpeg-devel] [PATCH] Remove REP_RET usage throughout x86 asm files

Henrik Gramner henrik at gramner.com
Mon Nov 13 18:29:29 EET 2017

On Sun, Nov 12, 2017 at 9:59 PM, Rostislav Pehlivanov
<atomnuker at gmail.com> wrote:
> No longer needed as AUTO_REP_RET deals with it on normal RETs.

Only when the RET follows a branch instruction. If it's a branch
target (that isn't by itself preceded by a branch instruction) there
is no way of automatically detecting whether or not a rep prefix
should be used as far as I know.

On the other hand, the CPU:s where it even matters in the first place
are old legacy stuff which aren't relevant any more and eliminating
those few cases (if there are any, I didn't check) for simplicity is
probably worth it anyway.

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