Move the query system to rustc_query_impl.

compiler/rustc_query_impl/src/keys.rs

@@ -0,0 +1,333 @@
+//! Defines the set of legal keys that can be used in queries.
+
+use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
+use rustc_middle::infer::canonical::Canonical;
+use rustc_middle::mir;
+use rustc_middle::ty::fast_reject::SimplifiedType;
+use rustc_middle::ty::subst::{GenericArg, SubstsRef};
+use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_span::symbol::{Ident, Symbol};
+use rustc_span::{Span, DUMMY_SP};
+
+/// The `Key` trait controls what types can legally be used as the key
+/// for a query.
+pub trait Key {
+    /// Given an instance of this key, what crate is it referring to?
+    /// This is used to find the provider.
+    fn query_crate(&self) -> CrateNum;
+
+    /// In the event that a cycle occurs, if no explicit span has been
+    /// given for a query with key `self`, what span should we use?
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span;
+}
+
+impl<'tcx> Key for ty::InstanceDef<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(self.def_id())
+    }
+}
+
+impl<'tcx> Key for ty::Instance<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(self.def_id())
+    }
+}
+
+impl<'tcx> Key for mir::interpret::GlobalId<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        self.instance.query_crate()
+    }
+
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.instance.default_span(tcx)
+    }
+}
+
+impl<'tcx> Key for mir::interpret::LitToConstInput<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl Key for CrateNum {
+    fn query_crate(&self) -> CrateNum {
+        *self
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl Key for LocalDefId {
+    fn query_crate(&self) -> CrateNum {
+        self.to_def_id().query_crate()
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.to_def_id().default_span(tcx)
+    }
+}
+
+impl Key for DefId {
+    fn query_crate(&self) -> CrateNum {
+        self.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(*self)
+    }
+}
+
+impl Key for ty::WithOptConstParam<LocalDefId> {
+    fn query_crate(&self) -> CrateNum {
+        self.did.query_crate()
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.did.default_span(tcx)
+    }
+}
+
+impl Key for (DefId, DefId) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.1.default_span(tcx)
+    }
+}
+
+impl Key for (ty::Instance<'tcx>, LocalDefId) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.query_crate()
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.0.default_span(tcx)
+    }
+}
+
+impl Key for (DefId, LocalDefId) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.1.default_span(tcx)
+    }
+}
+
+impl Key for (LocalDefId, DefId) {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.0.default_span(tcx)
+    }
+}
+
+impl Key for (DefId, Option<Ident>) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(self.0)
+    }
+}
+
+impl Key for (DefId, LocalDefId, Ident) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.1.default_span(tcx)
+    }
+}
+
+impl Key for (CrateNum, DefId) {
+    fn query_crate(&self) -> CrateNum {
+        self.0
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.1.default_span(tcx)
+    }
+}
+
+impl Key for (DefId, SimplifiedType) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.0.default_span(tcx)
+    }
+}
+
+impl<'tcx> Key for SubstsRef<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for (DefId, SubstsRef<'tcx>) {
+    fn query_crate(&self) -> CrateNum {
+        self.0.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.0.default_span(tcx)
+    }
+}
+
+impl<'tcx> Key
+    for (
+        (ty::WithOptConstParam<DefId>, SubstsRef<'tcx>),
+        (ty::WithOptConstParam<DefId>, SubstsRef<'tcx>),
+    )
+{
+    fn query_crate(&self) -> CrateNum {
+        (self.0).0.did.krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        (self.0).0.did.default_span(tcx)
+    }
+}
+
+impl<'tcx> Key for (LocalDefId, DefId, SubstsRef<'tcx>) {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.0.default_span(tcx)
+    }
+}
+
+impl<'tcx> Key for (ty::ParamEnv<'tcx>, ty::PolyTraitRef<'tcx>) {
+    fn query_crate(&self) -> CrateNum {
+        self.1.def_id().krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(self.1.def_id())
+    }
+}
+
+impl<'tcx> Key for (&'tcx ty::Const<'tcx>, mir::Field) {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for ty::PolyTraitRef<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        self.def_id().krate
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        tcx.def_span(self.def_id())
+    }
+}
+
+impl<'tcx> Key for GenericArg<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for &'tcx ty::Const<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for Ty<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for &'tcx ty::List<ty::Predicate<'tcx>> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for ty::ParamEnv<'tcx> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx, T: Key> Key for ty::ParamEnvAnd<'tcx, T> {
+    fn query_crate(&self) -> CrateNum {
+        self.value.query_crate()
+    }
+    fn default_span(&self, tcx: TyCtxt<'_>) -> Span {
+        self.value.default_span(tcx)
+    }
+}
+
+impl Key for Symbol {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+/// Canonical query goals correspond to abstract trait operations that
+/// are not tied to any crate in particular.
+impl<'tcx, T> Key for Canonical<'tcx, T> {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl Key for (Symbol, u32, u32) {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}
+
+impl<'tcx> Key for (DefId, Ty<'tcx>, SubstsRef<'tcx>, ty::ParamEnv<'tcx>) {
+    fn query_crate(&self) -> CrateNum {
+        LOCAL_CRATE
+    }
+
+    fn default_span(&self, _tcx: TyCtxt<'_>) -> Span {
+        DUMMY_SP
+    }
+}