[Bug target/121947] Improve X86_TUNE_DEST_FALSE_DEP_FOR_GLC implementation

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121947

--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Hongtao Liu from comment #4)
> (In reply to H.J. Lu from comment #3)
> > Created attachment 62385 [details]
> > A patch
> > 
> > This is a test patch:
> > 
> > 1. Move pass_x86_cse after pass_split_all_insns.
> > 2. Split 3 UNSPEC_INSN_FALSE_DEP patterns before RA.
> > 
> > Can we try if it works?
> 
> I'd rather keep the original implementation for below 2 reasons.
> 
> 1) It needs quite a lot of work to do it as splitter way, and more efforts
> for maintenance.
> 
> 2) The tune is only for SPR(GLC), and no longer needed for the
> successors(P-core) or any E-Core processors.

I noticed this with generic tuning. Can
we remove it from generic?