[Bug target/110751] RISC-V: Suport undefined value that allows VSETVL PASS use TA/MA

[juzhe.zhong at rivai dot ai via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110751

--- Comment #37 from JuzheZhong <juzhe.zhong at rivai dot ai> ---
(In reply to Richard Biener from comment #35)
> (In reply to Richard Biener from comment #34)
> > The ELSE value of type TYPE would be constructed like
> > 
> >  tree var = create_tmp_var (type);
> >  tree else_val = get_or_create_ssa_default_def (cfun, var);
> 
> Oh, and you recognize that at expansion by
> 
>   TREE_CODE (else_val) == SSA_NAAME
>   && SSA_NAME_IS_DEFAULT_DEF (else_val)
>   && VAR_P (SSA_NAME_VAR (else_val))

Oh. Sounds good. I will have a try.