[Bug target/70220] [x86] interrupt attribute optionally needs to provide read, write and control the set of saved registers

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70220

--- Comment #14 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Wink Saville from comment #13)
> > Compiler should be free to use rbp in anyway it sees fit. Spec shouldn't
> > say anything other than rbp is special to compiler.
> 
> If the compiler does decide to change rbp it must save original value,
> correct?

Yes.  But you don't know how/when it happens.