[Bug target/121947] Improve X86_TUNE_DEST_FALSE_DEP_FOR_GLC implementation

[hjl.tools at gmail dot com via Gcc-bugs]

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

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> ---
Created attachment 62385
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=62385&action=edit
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?