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

2020-01-12 Thread pinskia at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769 --- Comment #6 from Andrew Pinski --- (In reply to Segher Boessenkool from comment #5) > (In reply to Andrew Pinski from comment #4) > > >Linux system calls and Linux VDSO calls > > > > System calls, I can understand But why is it required by

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

2020-01-12 Thread segher at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769 --- Comment #5 from Segher Boessenkool --- (In reply to Andrew Pinski from comment #4) > >Linux system calls and Linux VDSO calls > > System calls, I can understand But why is it required by VDSO calls too? > That seems backwards and also mea

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

2020-01-11 Thread pinskia at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769 --- Comment #4 from Andrew Pinski --- >Linux system calls and Linux VDSO calls System calls, I can understand But why is it required by VDSO calls too? That seems backwards and also means VDSO functions are not the same ABI as normal function

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

2019-12-11 Thread segher at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769 --- Comment #3 from Segher Boessenkool --- (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.

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

2019-12-11 Thread christophe.le...@c-s.fr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92769 --- Comment #2 from Christophe Leroy --- 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 ? In our ABIs, r3 is also volatile in our ABIs, it doesn't prevent using it as