[Bug target/92769] Powerpc: No way to set CR0[SO] on function return

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769

--- Comment #3 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to Christophe Leroy from comment #2)
> But CR0 being volatile doesn't prevent GCC to set/clr its SO bit just before
> branching to LR as the ASM functions do, does it ?

Not at all, no.  But e.g. (linker-generated) glue code is free to clobber R0!

> In our ABIs, r3 is also volatile in our ABIs, it doesn't prevent using it as
> function return.



No, R3 is defined to be used as the return value.  CR0 is not.