https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112433
--- Comment #3 from JuzheZhong <juzhe.zhong at rivai dot ai> --- Just talked with Lehua offline. We don't think splitting RA can improve performance a lot. We should consider it more seriously instead of support this blindly. Since splitting RA will increase compile-time significantly with running RA twice (RA consume most of the compile-time).
