https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
Richard Biener changed:
What|Removed |Added
Keywords||missed-optimization
Priority|
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
Oleg Endo changed:
What|Removed |Added
Status|UNCONFIRMED |NEW
Last reconfirmed|
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #2 from Oleg Endo ---
(In reply to Oleg Endo from comment #1)
>
> Another more radical approach could be to insert an RTL pass that
> pre-allocates the R0 reg for those insns that have "z" constraint
> alternatives, similar to what K
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #3 from Oleg Endo ---
Created attachment 34982
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34982&action=edit
Add sh_pre_ra RTL pass
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #4 from Oleg Endo ---
(In reply to Oleg Endo from comment #3)
> Created attachment 34982 [details]
> Add sh_pre_ra RTL pass
Right now I can think of two alternatives for this PR:
- convert respective insns into insn_and_split and emi
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #5 from Oleg Endo ---
(In reply to Oleg Endo from comment #3)
> Created attachment 34982 [details]
> Add sh_pre_ra RTL pass
+
+ flag_live_range_shrinkage = 1;
This hunk was not supposed to be in the patch.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #6 from Kazumoto Kojima ---
(In reply to Oleg Endo from comment #4)
> I think that an SH specific pre-RA RTL pass could be useful in the future,
> for example to improve R0 utilization, even with LRA.
>
> Kaz, do you have any opinion
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64785
--- Comment #7 from Oleg Endo ---
(In reply to Kazumoto Kojima from comment #6)
>
> I like your pre-RA pass even if it's a too big hammer for
> this specific problem. It should wait the next stage1, though.
It seems that this PR's issue is not
