On Fri, Oct 11, 2019 at 3:52 PM Wilco Dijkstra <wilco.dijks...@arm.com> wrote: > > Hi Ramana, > > > My only question would be whether it's more suitable to use > > optimize_function_for_size_p(cfun) instead as IIRC that gives us a > > chance with lto rather than the global optimize_size. > > Yes that is even better and that defaults to optimize_size if cfun isn't > set. I've committed this: > > diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h > index > 8b67c9c3657b312be223ab60c01969958baa9ed3..5fad1e5bcc2bc448489fdc8239c676246bbc8879 > 100644 > --- a/gcc/config/arm/arm.h > +++ b/gcc/config/arm/arm.h > @@ -1068,9 +1068,8 @@ extern int arm_regs_in_sequence[]; > /* Use different register alloc ordering for Thumb. */ > #define ADJUST_REG_ALLOC_ORDER arm_order_regs_for_local_alloc () > > -/* Tell IRA to use the order we define rather than messing it up with its > - own cost calculations. */ > -#define HONOR_REG_ALLOC_ORDER 1 > +/* Tell IRA to use the order we define when optimizing for size. */ > +#define HONOR_REG_ALLOC_ORDER optimize_function_for_size_p (cfun)
I'd be happy with a patch that goes and looks at more such uses in the backend in your copious free time. hint hint. R > > /* Interrupt functions can only use registers that have already been > saved by the prologue, even if they would normally be