| //! Some facilities for tracking how codegen-units are reused during incremental |
| //! compilation. This is used for incremental compilation tests and debug |
| //! output. |
| |
| use crate::errors::{CguNotRecorded, IncorrectCguReuseType}; |
| use crate::Session; |
| use rustc_data_structures::fx::FxHashMap; |
| use rustc_errors::{DiagnosticArgValue, IntoDiagnosticArg}; |
| use rustc_span::{Span, Symbol}; |
| use std::borrow::Cow; |
| use std::fmt::{self}; |
| use std::sync::{Arc, Mutex}; |
| |
| #[derive(Copy, Clone, Debug, PartialEq, PartialOrd)] |
| pub enum CguReuse { |
| No, |
| PreLto, |
| PostLto, |
| } |
| |
| impl fmt::Display for CguReuse { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| match *self { |
| CguReuse::No => write!(f, "No"), |
| CguReuse::PreLto => write!(f, "PreLto "), |
| CguReuse::PostLto => write!(f, "PostLto "), |
| } |
| } |
| } |
| |
| impl IntoDiagnosticArg for CguReuse { |
| fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> { |
| DiagnosticArgValue::Str(Cow::Owned(self.to_string())) |
| } |
| } |
| |
| #[derive(Copy, Clone, Debug, PartialEq)] |
| pub enum ComparisonKind { |
| Exact, |
| AtLeast, |
| } |
| |
| struct TrackerData { |
| actual_reuse: FxHashMap<String, CguReuse>, |
| expected_reuse: FxHashMap<String, (String, SendSpan, CguReuse, ComparisonKind)>, |
| } |
| |
| // Span does not implement `Send`, so we can't just store it in the shared |
| // `TrackerData` object. Instead of splitting up `TrackerData` into shared and |
| // non-shared parts (which would be complicated), we just mark the `Span` here |
| // explicitly as `Send`. That's safe because the span data here is only ever |
| // accessed from the main thread. |
| struct SendSpan(Span); |
| unsafe impl Send for SendSpan {} |
| |
| #[derive(Clone)] |
| pub struct CguReuseTracker { |
| data: Option<Arc<Mutex<TrackerData>>>, |
| } |
| |
| impl CguReuseTracker { |
| pub fn new() -> CguReuseTracker { |
| let data = |
| TrackerData { actual_reuse: Default::default(), expected_reuse: Default::default() }; |
| |
| CguReuseTracker { data: Some(Arc::new(Mutex::new(data))) } |
| } |
| |
| pub fn new_disabled() -> CguReuseTracker { |
| CguReuseTracker { data: None } |
| } |
| |
| pub fn set_actual_reuse(&self, cgu_name: &str, kind: CguReuse) { |
| if let Some(ref data) = self.data { |
| debug!("set_actual_reuse({cgu_name:?}, {kind:?})"); |
| |
| let prev_reuse = data.lock().unwrap().actual_reuse.insert(cgu_name.to_string(), kind); |
| |
| if let Some(prev_reuse) = prev_reuse { |
| // The only time it is legal to overwrite reuse state is when |
| // we discover during ThinLTO that we can actually reuse the |
| // post-LTO version of a CGU. |
| assert_eq!(prev_reuse, CguReuse::PreLto); |
| } |
| } |
| } |
| |
| pub fn set_expectation( |
| &self, |
| cgu_name: Symbol, |
| cgu_user_name: &str, |
| error_span: Span, |
| expected_reuse: CguReuse, |
| comparison_kind: ComparisonKind, |
| ) { |
| if let Some(ref data) = self.data { |
| debug!("set_expectation({cgu_name:?}, {expected_reuse:?}, {comparison_kind:?})"); |
| let mut data = data.lock().unwrap(); |
| |
| data.expected_reuse.insert( |
| cgu_name.to_string(), |
| (cgu_user_name.to_string(), SendSpan(error_span), expected_reuse, comparison_kind), |
| ); |
| } |
| } |
| |
| pub fn check_expected_reuse(&self, sess: &Session) { |
| if let Some(ref data) = self.data { |
| let data = data.lock().unwrap(); |
| |
| for (cgu_name, &(ref cgu_user_name, ref error_span, expected_reuse, comparison_kind)) in |
| &data.expected_reuse |
| { |
| if let Some(&actual_reuse) = data.actual_reuse.get(cgu_name) { |
| let (error, at_least) = match comparison_kind { |
| ComparisonKind::Exact => (expected_reuse != actual_reuse, false), |
| ComparisonKind::AtLeast => (actual_reuse < expected_reuse, true), |
| }; |
| |
| if error { |
| let at_least = if at_least { 1 } else { 0 }; |
| IncorrectCguReuseType { |
| span: error_span.0, |
| cgu_user_name, |
| actual_reuse, |
| expected_reuse, |
| at_least, |
| }; |
| } |
| } else { |
| sess.emit_fatal(CguNotRecorded { cgu_user_name, cgu_name }); |
| } |
| } |
| } |
| } |
| } |