[Bug target/81312] Enable X86_TUNE_ACCUMULATE_OUTGOING_ARGS

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81312

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Jan Hubicka from comment #3)
> > Doesn't it improve performance in 64-bit mode?
> 
> It used to be important for CPUs without ESP prediction engines, but most of
> those are
> history now.  The codegen is quite different so it may be the case that it
> still helps
> somehow.  Do you have some data on the perfomrance?
> 

It is related to PR 81313.  Without it, GCC generates awful stack realignment
code.