170: check task priority at compile time r=TeXitoi a=japaric

before we were checking the priority at runtime. The compile time error message
when the priority is too high is kind of awful though.

Co-authored-by: Jorge Aparicio <jorge@japaric.io>
This commit is contained in:
bors[bot] 2019-04-16 22:54:18 +00:00
commit 77def32454
5 changed files with 55 additions and 6 deletions

View file

@ -1989,15 +1989,13 @@ fn pre_init(ctxt: &Context, app: &App, analysis: &Analysis) -> proc_macro2::Toke
))
}
// TODO turn the assertions that check that the priority is not larger than what's supported by
// the device into compile errors
let device = &app.args.device;
let nvic_prio_bits = quote!(#device::NVIC_PRIO_BITS);
for (handler, interrupt) in &app.interrupts {
let name = interrupt.args.binds(handler);
let priority = interrupt.args.priority;
exprs.push(quote!(p.NVIC.enable(#device::Interrupt::#name);));
exprs.push(quote!(assert!(#priority <= (1 << #nvic_prio_bits));));
exprs.push(quote!(let _ = [(); ((1 << #nvic_prio_bits) - #priority as usize)];));
exprs.push(quote!(p.NVIC.set_priority(
#device::Interrupt::#name,
((1 << #nvic_prio_bits) - #priority) << (8 - #nvic_prio_bits),
@ -2007,7 +2005,7 @@ fn pre_init(ctxt: &Context, app: &App, analysis: &Analysis) -> proc_macro2::Toke
for (priority, dispatcher) in &analysis.dispatchers {
let name = &dispatcher.interrupt;
exprs.push(quote!(p.NVIC.enable(#device::Interrupt::#name);));
exprs.push(quote!(assert!(#priority <= (1 << #nvic_prio_bits));));
exprs.push(quote!(let _ = [(); ((1 << #nvic_prio_bits) - #priority as usize)];));
exprs.push(quote!(p.NVIC.set_priority(
#device::Interrupt::#name,
((1 << #nvic_prio_bits) - #priority) << (8 - #nvic_prio_bits),

View file

@ -1039,10 +1039,10 @@ fn parse_args(
}
let value = lit.value();
if value > u64::from(u8::MAX) {
if value > u64::from(u8::MAX) || value == 0 {
return Err(parse::Error::new(
lit.span(),
"this literal must be in the range 0...255",
"this literal must be in the range 1...255",
));
}