| //! The implementation of the query system itself. This defines the macros that |
| //! generate the actual methods on tcx which find and execute the provider, |
| //! manage the caches, and so forth. |
| |
| use crate::dep_graph::DepGraph; |
| use crate::ty::query::Query; |
| use crate::ty::tls::{self, ImplicitCtxt}; |
| use crate::ty::{self, TyCtxt}; |
| use rustc_query_system::query::QueryContext; |
| use rustc_query_system::query::{CycleError, QueryJobId, QueryJobInfo}; |
| |
| use rustc_data_structures::fx::FxHashMap; |
| use rustc_data_structures::sync::Lock; |
| use rustc_data_structures::thin_vec::ThinVec; |
| use rustc_errors::{struct_span_err, Diagnostic, DiagnosticBuilder, Handler, Level}; |
| use rustc_span::def_id::DefId; |
| use rustc_span::Span; |
| |
| impl QueryContext for TyCtxt<'tcx> { |
| type Query = Query<'tcx>; |
| |
| fn incremental_verify_ich(&self) -> bool { |
| self.sess.opts.debugging_opts.incremental_verify_ich |
| } |
| fn verbose(&self) -> bool { |
| self.sess.verbose() |
| } |
| |
| fn def_path_str(&self, def_id: DefId) -> String { |
| TyCtxt::def_path_str(*self, def_id) |
| } |
| |
| fn dep_graph(&self) -> &DepGraph { |
| &self.dep_graph |
| } |
| |
| fn current_query_job(&self) -> Option<QueryJobId<Self::DepKind>> { |
| tls::with_related_context(*self, |icx| icx.query) |
| } |
| |
| fn try_collect_active_jobs( |
| &self, |
| ) -> Option<FxHashMap<QueryJobId<Self::DepKind>, QueryJobInfo<Self::DepKind, Self::Query>>> |
| { |
| self.queries.try_collect_active_jobs() |
| } |
| |
| /// Executes a job by changing the `ImplicitCtxt` to point to the |
| /// new query job while it executes. It returns the diagnostics |
| /// captured during execution and the actual result. |
| #[inline(always)] |
| fn start_query<R>( |
| &self, |
| token: QueryJobId<Self::DepKind>, |
| diagnostics: Option<&Lock<ThinVec<Diagnostic>>>, |
| compute: impl FnOnce(Self) -> R, |
| ) -> R { |
| // The `TyCtxt` stored in TLS has the same global interner lifetime |
| // as `self`, so we use `with_related_context` to relate the 'tcx lifetimes |
| // when accessing the `ImplicitCtxt`. |
| tls::with_related_context(*self, move |current_icx| { |
| // Update the `ImplicitCtxt` to point to our new query job. |
| let new_icx = ImplicitCtxt { |
| tcx: *self, |
| query: Some(token), |
| diagnostics, |
| layout_depth: current_icx.layout_depth, |
| task_deps: current_icx.task_deps, |
| }; |
| |
| // Use the `ImplicitCtxt` while we execute the query. |
| tls::enter_context(&new_icx, |_| { |
| rustc_data_structures::stack::ensure_sufficient_stack(|| compute(*self)) |
| }) |
| }) |
| } |
| } |
| |
| impl<'tcx> TyCtxt<'tcx> { |
| #[inline(never)] |
| #[cold] |
| pub(super) fn report_cycle( |
| self, |
| CycleError { usage, cycle: stack }: CycleError<Query<'tcx>>, |
| ) -> DiagnosticBuilder<'tcx> { |
| assert!(!stack.is_empty()); |
| |
| let fix_span = |span: Span, query: &Query<'tcx>| { |
| self.sess.source_map().guess_head_span(query.default_span(self, span)) |
| }; |
| |
| // Disable naming impls with types in this path, since that |
| // sometimes cycles itself, leading to extra cycle errors. |
| // (And cycle errors around impls tend to occur during the |
| // collect/coherence phases anyhow.) |
| ty::print::with_forced_impl_filename_line(|| { |
| let span = fix_span(stack[1 % stack.len()].span, &stack[0].query); |
| let mut err = struct_span_err!( |
| self.sess, |
| span, |
| E0391, |
| "cycle detected when {}", |
| stack[0].query.describe(self) |
| ); |
| |
| for i in 1..stack.len() { |
| let query = &stack[i].query; |
| let span = fix_span(stack[(i + 1) % stack.len()].span, query); |
| err.span_note(span, &format!("...which requires {}...", query.describe(self))); |
| } |
| |
| err.note(&format!( |
| "...which again requires {}, completing the cycle", |
| stack[0].query.describe(self) |
| )); |
| |
| if let Some((span, query)) = usage { |
| err.span_note( |
| fix_span(span, &query), |
| &format!("cycle used when {}", query.describe(self)), |
| ); |
| } |
| |
| err |
| }) |
| } |
| |
| pub fn try_print_query_stack(handler: &Handler, num_frames: Option<usize>) { |
| eprintln!("query stack during panic:"); |
| |
| // Be careful reyling on global state here: this code is called from |
| // a panic hook, which means that the global `Handler` may be in a weird |
| // state if it was responsible for triggering the panic. |
| let mut i = 0; |
| ty::tls::with_context_opt(|icx| { |
| if let Some(icx) = icx { |
| let query_map = icx.tcx.queries.try_collect_active_jobs(); |
| |
| let mut current_query = icx.query; |
| |
| while let Some(query) = current_query { |
| if Some(i) == num_frames { |
| break; |
| } |
| let query_info = |
| if let Some(info) = query_map.as_ref().and_then(|map| map.get(&query)) { |
| info |
| } else { |
| break; |
| }; |
| let mut diag = Diagnostic::new( |
| Level::FailureNote, |
| &format!( |
| "#{} [{}] {}", |
| i, |
| query_info.info.query.name(), |
| query_info.info.query.describe(icx.tcx) |
| ), |
| ); |
| diag.span = |
| icx.tcx.sess.source_map().guess_head_span(query_info.info.span).into(); |
| handler.force_print_diagnostic(diag); |
| |
| current_query = query_info.job.parent; |
| i += 1; |
| } |
| } |
| }); |
| |
| if num_frames == None || num_frames >= Some(i) { |
| eprintln!("end of query stack"); |
| } else { |
| eprintln!("we're just showing a limited slice of the query stack"); |
| } |
| } |
| } |
| |
| macro_rules! handle_cycle_error { |
| ([][$tcx: expr, $error:expr]) => {{ |
| $tcx.report_cycle($error).emit(); |
| Value::from_cycle_error($tcx) |
| }}; |
| ([fatal_cycle $($rest:tt)*][$tcx:expr, $error:expr]) => {{ |
| $tcx.report_cycle($error).emit(); |
| $tcx.sess.abort_if_errors(); |
| unreachable!() |
| }}; |
| ([cycle_delay_bug $($rest:tt)*][$tcx:expr, $error:expr]) => {{ |
| $tcx.report_cycle($error).delay_as_bug(); |
| Value::from_cycle_error($tcx) |
| }}; |
| ([$other:ident $(($($other_args:tt)*))* $(, $($modifiers:tt)*)*][$($args:tt)*]) => { |
| handle_cycle_error!([$($($modifiers)*)*][$($args)*]) |
| }; |
| } |
| |
| macro_rules! is_anon { |
| ([]) => {{ |
| false |
| }}; |
| ([anon $($rest:tt)*]) => {{ |
| true |
| }}; |
| ([$other:ident $(($($other_args:tt)*))* $(, $($modifiers:tt)*)*]) => { |
| is_anon!([$($($modifiers)*)*]) |
| }; |
| } |
| |
| macro_rules! is_eval_always { |
| ([]) => {{ |
| false |
| }}; |
| ([eval_always $($rest:tt)*]) => {{ |
| true |
| }}; |
| ([$other:ident $(($($other_args:tt)*))* $(, $($modifiers:tt)*)*]) => { |
| is_eval_always!([$($($modifiers)*)*]) |
| }; |
| } |
| |
| macro_rules! query_storage { |
| ([][$K:ty, $V:ty]) => { |
| <<$K as Key>::CacheSelector as CacheSelector<$K, $V>>::Cache |
| }; |
| ([storage($ty:ty) $($rest:tt)*][$K:ty, $V:ty]) => { |
| <$ty as CacheSelector<$K, $V>>::Cache |
| }; |
| ([$other:ident $(($($other_args:tt)*))* $(, $($modifiers:tt)*)*][$($args:tt)*]) => { |
| query_storage!([$($($modifiers)*)*][$($args)*]) |
| }; |
| } |
| |
| macro_rules! hash_result { |
| ([][$hcx:expr, $result:expr]) => {{ |
| dep_graph::hash_result($hcx, &$result) |
| }}; |
| ([no_hash $($rest:tt)*][$hcx:expr, $result:expr]) => {{ |
| None |
| }}; |
| ([$other:ident $(($($other_args:tt)*))* $(, $($modifiers:tt)*)*][$($args:tt)*]) => { |
| hash_result!([$($($modifiers)*)*][$($args)*]) |
| }; |
| } |
| |
| macro_rules! define_queries { |
| (<$tcx:tt> $($category:tt { |
| $($(#[$attr:meta])* [$($modifiers:tt)*] fn $name:ident: $node:ident($($K:tt)*) -> $V:ty,)* |
| },)*) => { |
| define_queries_inner! { <$tcx> |
| $($( $(#[$attr])* category<$category> [$($modifiers)*] fn $name: $node($($K)*) -> $V,)*)* |
| } |
| } |
| } |
| |
| macro_rules! query_helper_param_ty { |
| (DefId) => { impl IntoQueryParam<DefId> }; |
| ($K:ty) => { $K }; |
| } |
| |
| macro_rules! define_queries_inner { |
| (<$tcx:tt> |
| $($(#[$attr:meta])* category<$category:tt> |
| [$($modifiers:tt)*] fn $name:ident: $node:ident($($K:tt)*) -> $V:ty,)*) => { |
| |
| use std::mem; |
| use crate::{ |
| rustc_data_structures::stable_hasher::HashStable, |
| rustc_data_structures::stable_hasher::StableHasher, |
| ich::StableHashingContext |
| }; |
| use rustc_data_structures::profiling::ProfileCategory; |
| |
| define_queries_struct! { |
| tcx: $tcx, |
| input: ($(([$($modifiers)*] [$($attr)*] [$name]))*) |
| } |
| |
| #[allow(nonstandard_style)] |
| #[derive(Clone, Debug)] |
| pub enum Query<$tcx> { |
| $($(#[$attr])* $name($($K)*)),* |
| } |
| |
| impl<$tcx> Query<$tcx> { |
| pub fn name(&self) -> &'static str { |
| match *self { |
| $(Query::$name(_) => stringify!($name),)* |
| } |
| } |
| |
| pub fn describe(&self, tcx: TyCtxt<$tcx>) -> Cow<'static, str> { |
| let (r, name) = match *self { |
| $(Query::$name(key) => { |
| (queries::$name::describe(tcx, key), stringify!($name)) |
| })* |
| }; |
| if tcx.sess.verbose() { |
| format!("{} [{}]", r, name).into() |
| } else { |
| r |
| } |
| } |
| |
| // FIXME(eddyb) Get more valid `Span`s on queries. |
| pub fn default_span(&self, tcx: TyCtxt<$tcx>, span: Span) -> Span { |
| if !span.is_dummy() { |
| return span; |
| } |
| // The `def_span` query is used to calculate `default_span`, |
| // so exit to avoid infinite recursion. |
| if let Query::def_span(..) = *self { |
| return span |
| } |
| match *self { |
| $(Query::$name(key) => key.default_span(tcx),)* |
| } |
| } |
| } |
| |
| impl<'a, $tcx> HashStable<StableHashingContext<'a>> for Query<$tcx> { |
| fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) { |
| mem::discriminant(self).hash_stable(hcx, hasher); |
| match *self { |
| $(Query::$name(key) => key.hash_stable(hcx, hasher),)* |
| } |
| } |
| } |
| |
| #[allow(nonstandard_style)] |
| pub mod queries { |
| use std::marker::PhantomData; |
| |
| $(pub struct $name<$tcx> { |
| data: PhantomData<&$tcx ()> |
| })* |
| } |
| |
| // HACK(eddyb) this is like the `impl QueryConfig for queries::$name` |
| // below, but using type aliases instead of associated types, to bypass |
| // the limitations around normalizing under HRTB - for example, this: |
| // `for<'tcx> fn(...) -> <queries::$name<'tcx> as QueryConfig<TyCtxt<'tcx>>>::Value` |
| // doesn't currently normalize to `for<'tcx> fn(...) -> query_values::$name<'tcx>`. |
| // This is primarily used by the `provide!` macro in `rustc_metadata`. |
| #[allow(nonstandard_style, unused_lifetimes)] |
| pub mod query_keys { |
| use super::*; |
| |
| $(pub type $name<$tcx> = $($K)*;)* |
| } |
| #[allow(nonstandard_style, unused_lifetimes)] |
| pub mod query_values { |
| use super::*; |
| |
| $(pub type $name<$tcx> = $V;)* |
| } |
| |
| $(impl<$tcx> QueryConfig for queries::$name<$tcx> { |
| type Key = $($K)*; |
| type Value = $V; |
| type Stored = < |
| query_storage!([$($modifiers)*][$($K)*, $V]) |
| as QueryStorage |
| >::Stored; |
| const NAME: &'static str = stringify!($name); |
| const CATEGORY: ProfileCategory = $category; |
| } |
| |
| impl<$tcx> QueryAccessors<TyCtxt<$tcx>> for queries::$name<$tcx> { |
| const ANON: bool = is_anon!([$($modifiers)*]); |
| const EVAL_ALWAYS: bool = is_eval_always!([$($modifiers)*]); |
| const DEP_KIND: dep_graph::DepKind = dep_graph::DepKind::$node; |
| |
| type Cache = query_storage!([$($modifiers)*][$($K)*, $V]); |
| |
| #[inline(always)] |
| fn query_state<'a>(tcx: TyCtxt<$tcx>) -> &'a QueryState<crate::dep_graph::DepKind, <TyCtxt<$tcx> as QueryContext>::Query, Self::Cache> { |
| &tcx.queries.$name |
| } |
| |
| #[inline] |
| fn compute(tcx: TyCtxt<'tcx>, key: Self::Key) -> Self::Value { |
| let provider = tcx.queries.providers.get(key.query_crate()) |
| // HACK(eddyb) it's possible crates may be loaded after |
| // the query engine is created, and because crate loading |
| // is not yet integrated with the query engine, such crates |
| // would be missing appropriate entries in `providers`. |
| .unwrap_or(&tcx.queries.fallback_extern_providers) |
| .$name; |
| provider(tcx, key) |
| } |
| |
| fn hash_result( |
| _hcx: &mut StableHashingContext<'_>, |
| _result: &Self::Value |
| ) -> Option<Fingerprint> { |
| hash_result!([$($modifiers)*][_hcx, _result]) |
| } |
| |
| fn handle_cycle_error( |
| tcx: TyCtxt<'tcx>, |
| error: CycleError<Query<'tcx>> |
| ) -> Self::Value { |
| handle_cycle_error!([$($modifiers)*][tcx, error]) |
| } |
| })* |
| |
| #[derive(Copy, Clone)] |
| pub struct TyCtxtEnsure<'tcx> { |
| pub tcx: TyCtxt<'tcx>, |
| } |
| |
| impl TyCtxtEnsure<$tcx> { |
| $($(#[$attr])* |
| #[inline(always)] |
| pub fn $name(self, key: query_helper_param_ty!($($K)*)) { |
| ensure_query::<queries::$name<'_>, _>(self.tcx, key.into_query_param()) |
| })* |
| } |
| |
| #[derive(Copy, Clone)] |
| pub struct TyCtxtAt<'tcx> { |
| pub tcx: TyCtxt<'tcx>, |
| pub span: Span, |
| } |
| |
| impl Deref for TyCtxtAt<'tcx> { |
| type Target = TyCtxt<'tcx>; |
| #[inline(always)] |
| fn deref(&self) -> &Self::Target { |
| &self.tcx |
| } |
| } |
| |
| impl TyCtxt<$tcx> { |
| /// Returns a transparent wrapper for `TyCtxt`, which ensures queries |
| /// are executed instead of just returning their results. |
| #[inline(always)] |
| pub fn ensure(self) -> TyCtxtEnsure<$tcx> { |
| TyCtxtEnsure { |
| tcx: self, |
| } |
| } |
| |
| /// Returns a transparent wrapper for `TyCtxt` which uses |
| /// `span` as the location of queries performed through it. |
| #[inline(always)] |
| pub fn at(self, span: Span) -> TyCtxtAt<$tcx> { |
| TyCtxtAt { |
| tcx: self, |
| span |
| } |
| } |
| |
| $($(#[$attr])* |
| #[inline(always)] |
| #[must_use] |
| pub fn $name(self, key: query_helper_param_ty!($($K)*)) |
| -> <queries::$name<$tcx> as QueryConfig>::Stored |
| { |
| self.at(DUMMY_SP).$name(key.into_query_param()) |
| })* |
| |
| /// All self-profiling events generated by the query engine use |
| /// virtual `StringId`s for their `event_id`. This method makes all |
| /// those virtual `StringId`s point to actual strings. |
| /// |
| /// If we are recording only summary data, the ids will point to |
| /// just the query names. If we are recording query keys too, we |
| /// allocate the corresponding strings here. |
| pub fn alloc_self_profile_query_strings(self) { |
| use crate::ty::query::profiling_support::{ |
| alloc_self_profile_query_strings_for_query_cache, |
| QueryKeyStringCache, |
| }; |
| |
| if !self.prof.enabled() { |
| return; |
| } |
| |
| let mut string_cache = QueryKeyStringCache::new(); |
| |
| $({ |
| alloc_self_profile_query_strings_for_query_cache( |
| self, |
| stringify!($name), |
| &self.queries.$name, |
| &mut string_cache, |
| ); |
| })* |
| } |
| } |
| |
| impl TyCtxtAt<$tcx> { |
| $($(#[$attr])* |
| #[inline(always)] |
| pub fn $name(self, key: query_helper_param_ty!($($K)*)) |
| -> <queries::$name<$tcx> as QueryConfig>::Stored |
| { |
| get_query::<queries::$name<'_>, _>(self.tcx, self.span, key.into_query_param()) |
| })* |
| } |
| |
| define_provider_struct! { |
| tcx: $tcx, |
| input: ($(([$($modifiers)*] [$name] [$($K)*] [$V]))*) |
| } |
| |
| impl Copy for Providers {} |
| impl Clone for Providers { |
| fn clone(&self) -> Self { *self } |
| } |
| } |
| } |
| |
| // FIXME(eddyb) this macro (and others?) use `$tcx` and `'tcx` interchangeably. |
| // We should either not take `$tcx` at all and use `'tcx` everywhere, or use |
| // `$tcx` everywhere (even if that isn't necessary due to lack of hygiene). |
| macro_rules! define_queries_struct { |
| (tcx: $tcx:tt, |
| input: ($(([$($modifiers:tt)*] [$($attr:tt)*] [$name:ident]))*)) => { |
| pub struct Queries<$tcx> { |
| /// This provides access to the incrimental comilation on-disk cache for query results. |
| /// Do not access this directly. It is only meant to be used by |
| /// `DepGraph::try_mark_green()` and the query infrastructure. |
| pub(crate) on_disk_cache: OnDiskCache<'tcx>, |
| |
| providers: IndexVec<CrateNum, Providers>, |
| fallback_extern_providers: Box<Providers>, |
| |
| $($(#[$attr])* $name: QueryState< |
| crate::dep_graph::DepKind, |
| <TyCtxt<$tcx> as QueryContext>::Query, |
| <queries::$name<$tcx> as QueryAccessors<TyCtxt<'tcx>>>::Cache, |
| >,)* |
| } |
| |
| impl<$tcx> Queries<$tcx> { |
| pub(crate) fn new( |
| providers: IndexVec<CrateNum, Providers>, |
| fallback_extern_providers: Providers, |
| on_disk_cache: OnDiskCache<'tcx>, |
| ) -> Self { |
| Queries { |
| providers, |
| fallback_extern_providers: Box::new(fallback_extern_providers), |
| on_disk_cache, |
| $($name: Default::default()),* |
| } |
| } |
| |
| pub(crate) fn try_collect_active_jobs( |
| &self |
| ) -> Option<FxHashMap<QueryJobId<crate::dep_graph::DepKind>, QueryJobInfo<crate::dep_graph::DepKind, <TyCtxt<$tcx> as QueryContext>::Query>>> { |
| let mut jobs = FxHashMap::default(); |
| |
| $( |
| self.$name.try_collect_active_jobs( |
| <queries::$name<'tcx> as QueryAccessors<TyCtxt<'tcx>>>::DEP_KIND, |
| Query::$name, |
| &mut jobs, |
| )?; |
| )* |
| |
| Some(jobs) |
| } |
| } |
| }; |
| } |
| |
| macro_rules! define_provider_struct { |
| (tcx: $tcx:tt, |
| input: ($(([$($modifiers:tt)*] [$name:ident] [$K:ty] [$R:ty]))*)) => { |
| pub struct Providers { |
| $(pub $name: for<$tcx> fn(TyCtxt<$tcx>, $K) -> $R,)* |
| } |
| |
| impl Default for Providers { |
| fn default() -> Self { |
| $(fn $name<$tcx>(_: TyCtxt<$tcx>, key: $K) -> $R { |
| bug!("`tcx.{}({:?})` unsupported by its crate", |
| stringify!($name), key); |
| })* |
| Providers { $($name),* } |
| } |
| } |
| }; |
| } |