mv compiler to compiler/
This commit is contained in:
mark
Vadim Petrochenkov
parent
db534b3ac2
commit
9e5f7d5631
1686 changed files with 941 additions and 1051 deletions
588
compiler/rustc_traits/src/chalk/db.rs
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588
compiler/rustc_traits/src/chalk/db.rs
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@ -0,0 +1,588 @@
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//! Provides the `RustIrDatabase` implementation for `chalk-solve`
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//!
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//! The purpose of the `chalk_solve::RustIrDatabase` is to get data about
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//! specific types, such as bounds, where clauses, or fields. This file contains
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//! the minimal logic to assemble the types for `chalk-solve` by calling out to
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//! either the `TyCtxt` (for information about types) or
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//! `crate::chalk::lowering` (to lower rustc types into Chalk types).
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use rustc_middle::traits::ChalkRustInterner as RustInterner;
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use rustc_middle::ty::subst::{InternalSubsts, Subst, SubstsRef};
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use rustc_middle::ty::{self, AssocItemContainer, AssocKind, TyCtxt};
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use rustc_hir::def_id::DefId;
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use rustc_span::symbol::sym;
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use std::fmt;
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use std::sync::Arc;
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use crate::chalk::lowering::LowerInto;
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pub struct RustIrDatabase<'tcx> {
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pub tcx: TyCtxt<'tcx>,
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pub interner: RustInterner<'tcx>,
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}
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impl fmt::Debug for RustIrDatabase<'_> {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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write!(f, "RustIrDatabase")
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}
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}
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impl<'tcx> chalk_solve::RustIrDatabase<RustInterner<'tcx>> for RustIrDatabase<'tcx> {
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fn interner(&self) -> &RustInterner<'tcx> {
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&self.interner
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}
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fn associated_ty_data(
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&self,
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assoc_type_id: chalk_ir::AssocTypeId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::AssociatedTyDatum<RustInterner<'tcx>>> {
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let def_id = assoc_type_id.0;
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let assoc_item = self.tcx.associated_item(def_id);
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let trait_def_id = match assoc_item.container {
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AssocItemContainer::TraitContainer(def_id) => def_id,
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_ => unimplemented!("Not possible??"),
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};
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match assoc_item.kind {
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AssocKind::Type => {}
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_ => unimplemented!("Not possible??"),
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}
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let bound_vars = bound_vars_for_item(self.tcx, def_id);
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let binders = binders_for(&self.interner, bound_vars);
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// FIXME(chalk): this really isn't right I don't think. The functions
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// for GATs are a bit hard to figure out. Are these supposed to be where
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// clauses or bounds?
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let predicates = self.tcx.predicates_defined_on(def_id).predicates;
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
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.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
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Arc::new(chalk_solve::rust_ir::AssociatedTyDatum {
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trait_id: chalk_ir::TraitId(trait_def_id),
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id: assoc_type_id,
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name: (),
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binders: chalk_ir::Binders::new(
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binders,
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chalk_solve::rust_ir::AssociatedTyDatumBound { bounds: vec![], where_clauses },
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),
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})
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}
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fn trait_datum(
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&self,
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trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::TraitDatum<RustInterner<'tcx>>> {
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let def_id = trait_id.0;
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let trait_def = self.tcx.trait_def(def_id);
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let bound_vars = bound_vars_for_item(self.tcx, def_id);
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let binders = binders_for(&self.interner, bound_vars);
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let predicates = self.tcx.predicates_defined_on(def_id).predicates;
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
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.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
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let associated_ty_ids: Vec<_> = self
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.tcx
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.associated_items(def_id)
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.in_definition_order()
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.filter(|i| i.kind == AssocKind::Type)
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.map(|i| chalk_ir::AssocTypeId(i.def_id))
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.collect();
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let well_known =
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if self.tcx.lang_items().sized_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::Sized)
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} else if self.tcx.lang_items().copy_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::Copy)
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} else if self.tcx.lang_items().clone_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::Clone)
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} else if self.tcx.lang_items().drop_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::Drop)
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} else if self.tcx.lang_items().fn_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::Fn)
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} else if self.tcx.lang_items().fn_once_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::FnOnce)
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} else if self.tcx.lang_items().fn_mut_trait().map(|t| def_id == t).unwrap_or(false) {
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Some(chalk_solve::rust_ir::WellKnownTrait::FnMut)
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} else {
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None
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};
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Arc::new(chalk_solve::rust_ir::TraitDatum {
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id: trait_id,
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binders: chalk_ir::Binders::new(
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binders,
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chalk_solve::rust_ir::TraitDatumBound { where_clauses },
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),
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flags: chalk_solve::rust_ir::TraitFlags {
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auto: trait_def.has_auto_impl,
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marker: trait_def.is_marker,
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upstream: !def_id.is_local(),
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fundamental: self.tcx.has_attr(def_id, sym::fundamental),
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non_enumerable: true,
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coinductive: false,
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},
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associated_ty_ids,
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well_known,
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})
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}
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fn adt_datum(
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&self,
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adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::AdtDatum<RustInterner<'tcx>>> {
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let adt_def = adt_id.0;
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let bound_vars = bound_vars_for_item(self.tcx, adt_def.did);
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let binders = binders_for(&self.interner, bound_vars);
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let predicates = self.tcx.predicates_of(adt_def.did).predicates;
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, bound_vars))
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.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner))
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.collect();
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let fields = match adt_def.adt_kind() {
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ty::AdtKind::Struct | ty::AdtKind::Union => {
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let variant = adt_def.non_enum_variant();
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variant
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.fields
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.iter()
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.map(|field| {
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self.tcx
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.type_of(field.did)
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.subst(self.tcx, bound_vars)
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.lower_into(&self.interner)
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})
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.collect()
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}
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// FIXME(chalk): handle enums; force_impl_for requires this
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ty::AdtKind::Enum => vec![],
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};
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let struct_datum = Arc::new(chalk_solve::rust_ir::AdtDatum {
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id: adt_id,
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binders: chalk_ir::Binders::new(
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binders,
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chalk_solve::rust_ir::AdtDatumBound { fields, where_clauses },
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),
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flags: chalk_solve::rust_ir::AdtFlags {
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upstream: !adt_def.did.is_local(),
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fundamental: adt_def.is_fundamental(),
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phantom_data: adt_def.is_phantom_data(),
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},
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});
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struct_datum
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}
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fn fn_def_datum(
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&self,
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fn_def_id: chalk_ir::FnDefId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::FnDefDatum<RustInterner<'tcx>>> {
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let def_id = fn_def_id.0;
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let bound_vars = bound_vars_for_item(self.tcx, def_id);
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let binders = binders_for(&self.interner, bound_vars);
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let predicates = self.tcx.predicates_defined_on(def_id).predicates;
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
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.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
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let sig = self.tcx.fn_sig(def_id);
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let inputs_and_output = sig.inputs_and_output();
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let (inputs_and_output, iobinders, _) = crate::chalk::lowering::collect_bound_vars(
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&self.interner,
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self.tcx,
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&inputs_and_output,
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);
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let argument_types = inputs_and_output[..inputs_and_output.len() - 1]
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.iter()
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.map(|t| t.subst(self.tcx, &bound_vars).lower_into(&self.interner))
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.collect();
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let return_type = inputs_and_output[inputs_and_output.len() - 1]
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.subst(self.tcx, &bound_vars)
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.lower_into(&self.interner);
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let bound = chalk_solve::rust_ir::FnDefDatumBound {
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inputs_and_output: chalk_ir::Binders::new(
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iobinders,
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chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
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),
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where_clauses,
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};
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Arc::new(chalk_solve::rust_ir::FnDefDatum {
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id: fn_def_id,
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abi: sig.abi(),
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binders: chalk_ir::Binders::new(binders, bound),
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})
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}
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fn impl_datum(
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&self,
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impl_id: chalk_ir::ImplId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::ImplDatum<RustInterner<'tcx>>> {
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let def_id = impl_id.0;
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let bound_vars = bound_vars_for_item(self.tcx, def_id);
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let binders = binders_for(&self.interner, bound_vars);
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let trait_ref = self.tcx.impl_trait_ref(def_id).expect("not an impl");
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let trait_ref = trait_ref.subst(self.tcx, bound_vars);
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let predicates = self.tcx.predicates_of(def_id).predicates;
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, bound_vars))
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.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
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let value = chalk_solve::rust_ir::ImplDatumBound {
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trait_ref: trait_ref.lower_into(&self.interner),
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where_clauses,
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};
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Arc::new(chalk_solve::rust_ir::ImplDatum {
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polarity: chalk_solve::rust_ir::Polarity::Positive,
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binders: chalk_ir::Binders::new(binders, value),
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impl_type: chalk_solve::rust_ir::ImplType::Local,
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associated_ty_value_ids: vec![],
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})
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}
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fn impls_for_trait(
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&self,
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trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
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parameters: &[chalk_ir::GenericArg<RustInterner<'tcx>>],
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) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
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let def_id = trait_id.0;
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// FIXME(chalk): use TraitDef::for_each_relevant_impl, but that will
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// require us to be able to interconvert `Ty<'tcx>`, and we're
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// not there yet.
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let all_impls = self.tcx.all_impls(def_id);
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let matched_impls = all_impls.filter(|impl_def_id| {
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use chalk_ir::could_match::CouldMatch;
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let trait_ref = self.tcx.impl_trait_ref(*impl_def_id).unwrap();
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let bound_vars = bound_vars_for_item(self.tcx, *impl_def_id);
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let self_ty = trait_ref.self_ty();
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let self_ty = self_ty.subst(self.tcx, bound_vars);
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let lowered_ty = self_ty.lower_into(&self.interner);
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parameters[0].assert_ty_ref(&self.interner).could_match(&self.interner, &lowered_ty)
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});
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let impls = matched_impls.map(chalk_ir::ImplId).collect();
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impls
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}
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fn impl_provided_for(
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&self,
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auto_trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
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adt_id: chalk_ir::AdtId<RustInterner<'tcx>>,
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) -> bool {
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let trait_def_id = auto_trait_id.0;
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let adt_def = adt_id.0;
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let all_impls = self.tcx.all_impls(trait_def_id);
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for impl_def_id in all_impls {
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let trait_ref = self.tcx.impl_trait_ref(impl_def_id).unwrap();
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let self_ty = trait_ref.self_ty();
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match self_ty.kind {
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ty::Adt(impl_adt_def, _) => {
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if impl_adt_def == adt_def {
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return true;
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}
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}
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_ => {}
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}
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}
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false
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}
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fn associated_ty_value(
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&self,
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associated_ty_id: chalk_solve::rust_ir::AssociatedTyValueId<RustInterner<'tcx>>,
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) -> Arc<chalk_solve::rust_ir::AssociatedTyValue<RustInterner<'tcx>>> {
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let def_id = associated_ty_id.0;
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let assoc_item = self.tcx.associated_item(def_id);
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let impl_id = match assoc_item.container {
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AssocItemContainer::TraitContainer(def_id) => def_id,
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_ => unimplemented!("Not possible??"),
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};
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match assoc_item.kind {
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AssocKind::Type => {}
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_ => unimplemented!("Not possible??"),
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}
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let bound_vars = bound_vars_for_item(self.tcx, def_id);
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let binders = binders_for(&self.interner, bound_vars);
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let ty = self.tcx.type_of(def_id);
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Arc::new(chalk_solve::rust_ir::AssociatedTyValue {
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impl_id: chalk_ir::ImplId(impl_id),
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associated_ty_id: chalk_ir::AssocTypeId(def_id),
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value: chalk_ir::Binders::new(
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binders,
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chalk_solve::rust_ir::AssociatedTyValueBound { ty: ty.lower_into(&self.interner) },
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),
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||||
})
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}
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fn custom_clauses(&self) -> Vec<chalk_ir::ProgramClause<RustInterner<'tcx>>> {
|
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vec![]
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}
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fn local_impls_to_coherence_check(
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&self,
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_trait_id: chalk_ir::TraitId<RustInterner<'tcx>>,
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||||
) -> Vec<chalk_ir::ImplId<RustInterner<'tcx>>> {
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unimplemented!()
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}
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fn opaque_ty_data(
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&self,
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opaque_ty_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
|
||||
) -> Arc<chalk_solve::rust_ir::OpaqueTyDatum<RustInterner<'tcx>>> {
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let bound_vars = bound_vars_for_item(self.tcx, opaque_ty_id.0);
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let binders = binders_for(&self.interner, bound_vars);
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let predicates = self.tcx.predicates_defined_on(opaque_ty_id.0).predicates;
|
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let where_clauses: Vec<_> = predicates
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.iter()
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.map(|(wc, _)| wc.subst(self.tcx, &bound_vars))
|
||||
.filter_map(|wc| LowerInto::<Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>::lower_into(wc, &self.interner)).collect();
|
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|
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let value = chalk_solve::rust_ir::OpaqueTyDatumBound {
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bounds: chalk_ir::Binders::new(binders, where_clauses),
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};
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Arc::new(chalk_solve::rust_ir::OpaqueTyDatum {
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opaque_ty_id,
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bound: chalk_ir::Binders::new(chalk_ir::VariableKinds::new(&self.interner), value),
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||||
})
|
||||
}
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||||
|
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/// Since Chalk can't handle all Rust types currently, we have to handle
|
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/// some specially for now. Over time, these `Some` returns will change to
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/// `None` and eventually this function will be removed.
|
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fn force_impl_for(
|
||||
&self,
|
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well_known: chalk_solve::rust_ir::WellKnownTrait,
|
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ty: &chalk_ir::TyData<RustInterner<'tcx>>,
|
||||
) -> Option<bool> {
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use chalk_ir::TyData::*;
|
||||
match well_known {
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||||
chalk_solve::rust_ir::WellKnownTrait::Sized => match ty {
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||||
Apply(apply) => match apply.name {
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||||
chalk_ir::TypeName::Adt(chalk_ir::AdtId(adt_def)) => match adt_def.adt_kind() {
|
||||
ty::AdtKind::Struct | ty::AdtKind::Union => None,
|
||||
ty::AdtKind::Enum => {
|
||||
let constraint = self.tcx.adt_sized_constraint(adt_def.did);
|
||||
if !constraint.0.is_empty() { unimplemented!() } else { Some(true) }
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||||
}
|
||||
},
|
||||
_ => None,
|
||||
},
|
||||
Dyn(_)
|
||||
| Alias(_)
|
||||
| Placeholder(_)
|
||||
| Function(_)
|
||||
| InferenceVar(_, _)
|
||||
| BoundVar(_) => None,
|
||||
},
|
||||
chalk_solve::rust_ir::WellKnownTrait::Copy
|
||||
| chalk_solve::rust_ir::WellKnownTrait::Clone => match ty {
|
||||
Apply(apply) => match apply.name {
|
||||
chalk_ir::TypeName::Adt(chalk_ir::AdtId(adt_def)) => match adt_def.adt_kind() {
|
||||
ty::AdtKind::Struct | ty::AdtKind::Union => None,
|
||||
ty::AdtKind::Enum => {
|
||||
let constraint = self.tcx.adt_sized_constraint(adt_def.did);
|
||||
if !constraint.0.is_empty() { unimplemented!() } else { Some(true) }
|
||||
}
|
||||
},
|
||||
_ => None,
|
||||
},
|
||||
Dyn(_)
|
||||
| Alias(_)
|
||||
| Placeholder(_)
|
||||
| Function(_)
|
||||
| InferenceVar(_, _)
|
||||
| BoundVar(_) => None,
|
||||
},
|
||||
chalk_solve::rust_ir::WellKnownTrait::Drop => None,
|
||||
chalk_solve::rust_ir::WellKnownTrait::Fn => None,
|
||||
chalk_solve::rust_ir::WellKnownTrait::FnMut => None,
|
||||
chalk_solve::rust_ir::WellKnownTrait::FnOnce => None,
|
||||
chalk_solve::rust_ir::WellKnownTrait::Unsize => None,
|
||||
}
|
||||
}
|
||||
|
||||
fn program_clauses_for_env(
|
||||
&self,
|
||||
environment: &chalk_ir::Environment<RustInterner<'tcx>>,
|
||||
) -> chalk_ir::ProgramClauses<RustInterner<'tcx>> {
|
||||
chalk_solve::program_clauses_for_env(self, environment)
|
||||
}
|
||||
|
||||
fn well_known_trait_id(
|
||||
&self,
|
||||
well_known_trait: chalk_solve::rust_ir::WellKnownTrait,
|
||||
) -> Option<chalk_ir::TraitId<RustInterner<'tcx>>> {
|
||||
use chalk_solve::rust_ir::WellKnownTrait::*;
|
||||
let def_id = match well_known_trait {
|
||||
Sized => self.tcx.lang_items().sized_trait(),
|
||||
Copy => self.tcx.lang_items().copy_trait(),
|
||||
Clone => self.tcx.lang_items().clone_trait(),
|
||||
Drop => self.tcx.lang_items().drop_trait(),
|
||||
Fn => self.tcx.lang_items().fn_trait(),
|
||||
FnMut => self.tcx.lang_items().fn_mut_trait(),
|
||||
FnOnce => self.tcx.lang_items().fn_once_trait(),
|
||||
Unsize => self.tcx.lang_items().unsize_trait(),
|
||||
};
|
||||
def_id.map(chalk_ir::TraitId)
|
||||
}
|
||||
|
||||
fn is_object_safe(&self, trait_id: chalk_ir::TraitId<RustInterner<'tcx>>) -> bool {
|
||||
self.tcx.is_object_safe(trait_id.0)
|
||||
}
|
||||
|
||||
fn hidden_opaque_type(
|
||||
&self,
|
||||
_id: chalk_ir::OpaqueTyId<RustInterner<'tcx>>,
|
||||
) -> chalk_ir::Ty<RustInterner<'tcx>> {
|
||||
// FIXME(chalk): actually get hidden ty
|
||||
self.tcx.mk_ty(ty::Tuple(self.tcx.intern_substs(&[]))).lower_into(&self.interner)
|
||||
}
|
||||
|
||||
fn closure_kind(
|
||||
&self,
|
||||
_closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
|
||||
substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
|
||||
) -> chalk_solve::rust_ir::ClosureKind {
|
||||
let kind = &substs.parameters(&self.interner)[substs.len(&self.interner) - 3];
|
||||
match kind.assert_ty_ref(&self.interner).data(&self.interner) {
|
||||
chalk_ir::TyData::Apply(apply) => match apply.name {
|
||||
chalk_ir::TypeName::Scalar(scalar) => match scalar {
|
||||
chalk_ir::Scalar::Int(int_ty) => match int_ty {
|
||||
chalk_ir::IntTy::I8 => chalk_solve::rust_ir::ClosureKind::Fn,
|
||||
chalk_ir::IntTy::I16 => chalk_solve::rust_ir::ClosureKind::FnMut,
|
||||
chalk_ir::IntTy::I32 => chalk_solve::rust_ir::ClosureKind::FnOnce,
|
||||
_ => bug!("bad closure kind"),
|
||||
},
|
||||
_ => bug!("bad closure kind"),
|
||||
},
|
||||
_ => bug!("bad closure kind"),
|
||||
},
|
||||
_ => bug!("bad closure kind"),
|
||||
}
|
||||
}
|
||||
|
||||
fn closure_inputs_and_output(
|
||||
&self,
|
||||
_closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
|
||||
substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
|
||||
) -> chalk_ir::Binders<chalk_solve::rust_ir::FnDefInputsAndOutputDatum<RustInterner<'tcx>>>
|
||||
{
|
||||
let sig = &substs.parameters(&self.interner)[substs.len(&self.interner) - 2];
|
||||
match sig.assert_ty_ref(&self.interner).data(&self.interner) {
|
||||
chalk_ir::TyData::Function(f) => {
|
||||
let substitution = f.substitution.parameters(&self.interner);
|
||||
let return_type =
|
||||
substitution.last().unwrap().assert_ty_ref(&self.interner).clone();
|
||||
// Closure arguments are tupled
|
||||
let argument_tuple = substitution[0].assert_ty_ref(&self.interner);
|
||||
let argument_types = match argument_tuple.data(&self.interner) {
|
||||
chalk_ir::TyData::Apply(apply) => match apply.name {
|
||||
chalk_ir::TypeName::Tuple(_) => apply
|
||||
.substitution
|
||||
.iter(&self.interner)
|
||||
.map(|arg| arg.assert_ty_ref(&self.interner))
|
||||
.cloned()
|
||||
.collect(),
|
||||
_ => bug!("Expecting closure FnSig args to be tupled."),
|
||||
},
|
||||
_ => bug!("Expecting closure FnSig args to be tupled."),
|
||||
};
|
||||
|
||||
chalk_ir::Binders::new(
|
||||
chalk_ir::VariableKinds::from(
|
||||
&self.interner,
|
||||
(0..f.num_binders).map(|_| chalk_ir::VariableKind::Lifetime),
|
||||
),
|
||||
chalk_solve::rust_ir::FnDefInputsAndOutputDatum { argument_types, return_type },
|
||||
)
|
||||
}
|
||||
_ => panic!("Invalid sig."),
|
||||
}
|
||||
}
|
||||
|
||||
fn closure_upvars(
|
||||
&self,
|
||||
_closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
|
||||
substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
|
||||
) -> chalk_ir::Binders<chalk_ir::Ty<RustInterner<'tcx>>> {
|
||||
let inputs_and_output = self.closure_inputs_and_output(_closure_id, substs);
|
||||
let tuple = substs.parameters(&self.interner).last().unwrap().assert_ty_ref(&self.interner);
|
||||
inputs_and_output.map_ref(|_| tuple.clone())
|
||||
}
|
||||
|
||||
fn closure_fn_substitution(
|
||||
&self,
|
||||
_closure_id: chalk_ir::ClosureId<RustInterner<'tcx>>,
|
||||
substs: &chalk_ir::Substitution<RustInterner<'tcx>>,
|
||||
) -> chalk_ir::Substitution<RustInterner<'tcx>> {
|
||||
let substitution = &substs.parameters(&self.interner)[0..substs.len(&self.interner) - 3];
|
||||
chalk_ir::Substitution::from(&self.interner, substitution)
|
||||
}
|
||||
}
|
||||
|
||||
/// Creates a `InternalSubsts` that maps each generic parameter to a higher-ranked
|
||||
/// var bound at index `0`. For types, we use a `BoundVar` index equal to
|
||||
/// the type parameter index. For regions, we use the `BoundRegion::BrNamed`
|
||||
/// variant (which has a `DefId`).
|
||||
fn bound_vars_for_item(tcx: TyCtxt<'tcx>, def_id: DefId) -> SubstsRef<'tcx> {
|
||||
InternalSubsts::for_item(tcx, def_id, |param, substs| match param.kind {
|
||||
ty::GenericParamDefKind::Type { .. } => tcx
|
||||
.mk_ty(ty::Bound(
|
||||
ty::INNERMOST,
|
||||
ty::BoundTy {
|
||||
var: ty::BoundVar::from(param.index),
|
||||
kind: ty::BoundTyKind::Param(param.name),
|
||||
},
|
||||
))
|
||||
.into(),
|
||||
|
||||
ty::GenericParamDefKind::Lifetime => tcx
|
||||
.mk_region(ty::RegionKind::ReLateBound(
|
||||
ty::INNERMOST,
|
||||
ty::BoundRegion::BrAnon(substs.len() as u32),
|
||||
))
|
||||
.into(),
|
||||
|
||||
ty::GenericParamDefKind::Const => tcx
|
||||
.mk_const(ty::Const {
|
||||
val: ty::ConstKind::Bound(ty::INNERMOST, ty::BoundVar::from(param.index)),
|
||||
ty: tcx.type_of(param.def_id),
|
||||
})
|
||||
.into(),
|
||||
})
|
||||
}
|
||||
|
||||
fn binders_for<'tcx>(
|
||||
interner: &RustInterner<'tcx>,
|
||||
bound_vars: SubstsRef<'tcx>,
|
||||
) -> chalk_ir::VariableKinds<RustInterner<'tcx>> {
|
||||
chalk_ir::VariableKinds::from(
|
||||
interner,
|
||||
bound_vars.iter().map(|arg| match arg.unpack() {
|
||||
ty::subst::GenericArgKind::Lifetime(_re) => chalk_ir::VariableKind::Lifetime,
|
||||
ty::subst::GenericArgKind::Type(_ty) => {
|
||||
chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General)
|
||||
}
|
||||
ty::subst::GenericArgKind::Const(c) => {
|
||||
chalk_ir::VariableKind::Const(c.ty.lower_into(interner))
|
||||
}
|
||||
}),
|
||||
)
|
||||
}
|
||||
886
compiler/rustc_traits/src/chalk/lowering.rs
Normal file
886
compiler/rustc_traits/src/chalk/lowering.rs
Normal file
|
|
@ -0,0 +1,886 @@
|
|||
//! Contains the logic to lower rustc types into Chalk types
|
||||
//!
|
||||
//! In many cases there is a 1:1 relationship between a rustc type and a Chalk type.
|
||||
//! For example, a `SubstsRef` maps almost directly to a `Substitution`. In some
|
||||
//! other cases, such as `Param`s, there is no Chalk type, so we have to handle
|
||||
//! accordingly.
|
||||
//!
|
||||
//! ## `Ty` lowering
|
||||
//! Much of the `Ty` lowering is 1:1 with Chalk. (Or will be eventually). A
|
||||
//! helpful table for what types lower to what can be found in the
|
||||
//! [Chalk book](http://rust-lang.github.io/chalk/book/types/rust_types.html).
|
||||
//! The most notable difference lies with `Param`s. To convert from rustc to
|
||||
//! Chalk, we eagerly and deeply convert `Param`s to placeholders (in goals) or
|
||||
//! bound variables (for clause generation through functions in `db`).
|
||||
//!
|
||||
//! ## `Region` lowering
|
||||
//! Regions are handled in rustc and Chalk is quite differently. In rustc, there
|
||||
//! is a difference between "early bound" and "late bound" regions, where only
|
||||
//! the late bound regions have a `DebruijnIndex`. Moreover, in Chalk all
|
||||
//! regions (Lifetimes) have an associated index. In rustc, only `BrAnon`s have
|
||||
//! an index, whereas `BrNamed` don't. In order to lower regions to Chalk, we
|
||||
//! convert all regions into `BrAnon` late-bound regions.
|
||||
//!
|
||||
//! ## `Const` lowering
|
||||
//! Chalk doesn't handle consts currently, so consts are currently lowered to
|
||||
//! an empty tuple.
|
||||
//!
|
||||
//! ## Bound variable collection
|
||||
//! Another difference between rustc and Chalk lies in the handling of binders.
|
||||
//! Chalk requires that we store the bound parameter kinds, whereas rustc does
|
||||
//! not. To lower anything wrapped in a `Binder`, we first deeply find any bound
|
||||
//! variables from the current `Binder`.
|
||||
|
||||
use rustc_middle::traits::{
|
||||
ChalkEnvironmentAndGoal, ChalkEnvironmentClause, ChalkRustInterner as RustInterner,
|
||||
};
|
||||
use rustc_middle::ty::fold::TypeFolder;
|
||||
use rustc_middle::ty::subst::{GenericArg, GenericArgKind, SubstsRef};
|
||||
use rustc_middle::ty::{
|
||||
self, Binder, BoundRegion, Region, RegionKind, Ty, TyCtxt, TyKind, TypeFoldable, TypeVisitor,
|
||||
};
|
||||
use rustc_span::def_id::DefId;
|
||||
|
||||
use std::collections::btree_map::{BTreeMap, Entry};
|
||||
|
||||
use chalk_ir::fold::shift::Shift;
|
||||
|
||||
/// Essentially an `Into` with a `&RustInterner` parameter
|
||||
crate trait LowerInto<'tcx, T> {
|
||||
/// Lower a rustc construct (e.g., `ty::TraitPredicate`) to a chalk type, consuming `self`.
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> T;
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::Substitution<RustInterner<'tcx>>> for SubstsRef<'tcx> {
|
||||
fn lower_into(
|
||||
self,
|
||||
interner: &RustInterner<'tcx>,
|
||||
) -> chalk_ir::Substitution<RustInterner<'tcx>> {
|
||||
chalk_ir::Substitution::from(interner, self.iter().map(|s| s.lower_into(interner)))
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::AliasTy<RustInterner<'tcx>>> for ty::ProjectionTy<'tcx> {
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::AliasTy<RustInterner<'tcx>> {
|
||||
chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy {
|
||||
associated_ty_id: chalk_ir::AssocTypeId(self.item_def_id),
|
||||
substitution: self.substs.lower_into(interner),
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'tcx>>>>
|
||||
for ChalkEnvironmentAndGoal<'tcx>
|
||||
{
|
||||
fn lower_into(
|
||||
self,
|
||||
interner: &RustInterner<'tcx>,
|
||||
) -> chalk_ir::InEnvironment<chalk_ir::Goal<RustInterner<'tcx>>> {
|
||||
let clauses = self.environment.into_iter().filter_map(|clause| match clause {
|
||||
ChalkEnvironmentClause::Predicate(predicate) => {
|
||||
// FIXME(chalk): forall
|
||||
match predicate.bound_atom(interner.tcx).skip_binder() {
|
||||
ty::PredicateAtom::Trait(predicate, _) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
Some(
|
||||
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::ProgramClauseImplication {
|
||||
consequence: chalk_ir::DomainGoal::FromEnv(
|
||||
chalk_ir::FromEnv::Trait(
|
||||
predicate.trait_ref.lower_into(interner),
|
||||
),
|
||||
),
|
||||
conditions: chalk_ir::Goals::new(interner),
|
||||
priority: chalk_ir::ClausePriority::High,
|
||||
},
|
||||
))
|
||||
.intern(interner),
|
||||
)
|
||||
}
|
||||
ty::PredicateAtom::RegionOutlives(predicate) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
Some(
|
||||
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::ProgramClauseImplication {
|
||||
consequence: chalk_ir::DomainGoal::Holds(
|
||||
chalk_ir::WhereClause::LifetimeOutlives(
|
||||
chalk_ir::LifetimeOutlives {
|
||||
a: predicate.0.lower_into(interner),
|
||||
b: predicate.1.lower_into(interner),
|
||||
},
|
||||
),
|
||||
),
|
||||
conditions: chalk_ir::Goals::new(interner),
|
||||
priority: chalk_ir::ClausePriority::High,
|
||||
},
|
||||
))
|
||||
.intern(interner),
|
||||
)
|
||||
}
|
||||
// FIXME(chalk): need to add TypeOutlives
|
||||
ty::PredicateAtom::TypeOutlives(_) => None,
|
||||
ty::PredicateAtom::Projection(predicate) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
Some(
|
||||
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::ProgramClauseImplication {
|
||||
consequence: chalk_ir::DomainGoal::Holds(
|
||||
chalk_ir::WhereClause::AliasEq(
|
||||
predicate.lower_into(interner),
|
||||
),
|
||||
),
|
||||
conditions: chalk_ir::Goals::new(interner),
|
||||
priority: chalk_ir::ClausePriority::High,
|
||||
},
|
||||
))
|
||||
.intern(interner),
|
||||
)
|
||||
}
|
||||
ty::PredicateAtom::WellFormed(..)
|
||||
| ty::PredicateAtom::ObjectSafe(..)
|
||||
| ty::PredicateAtom::ClosureKind(..)
|
||||
| ty::PredicateAtom::Subtype(..)
|
||||
| ty::PredicateAtom::ConstEvaluatable(..)
|
||||
| ty::PredicateAtom::ConstEquate(..) => {
|
||||
bug!("unexpected predicate {}", predicate)
|
||||
}
|
||||
}
|
||||
}
|
||||
ChalkEnvironmentClause::TypeFromEnv(ty) => Some(
|
||||
chalk_ir::ProgramClauseData(chalk_ir::Binders::new(
|
||||
chalk_ir::VariableKinds::new(interner),
|
||||
chalk_ir::ProgramClauseImplication {
|
||||
consequence: chalk_ir::DomainGoal::FromEnv(chalk_ir::FromEnv::Ty(
|
||||
ty.lower_into(interner).shifted_in(interner),
|
||||
)),
|
||||
conditions: chalk_ir::Goals::new(interner),
|
||||
priority: chalk_ir::ClausePriority::High,
|
||||
},
|
||||
))
|
||||
.intern(interner),
|
||||
),
|
||||
});
|
||||
|
||||
let goal: chalk_ir::GoalData<RustInterner<'tcx>> = self.goal.lower_into(&interner);
|
||||
chalk_ir::InEnvironment {
|
||||
environment: chalk_ir::Environment {
|
||||
clauses: chalk_ir::ProgramClauses::from(&interner, clauses),
|
||||
},
|
||||
goal: goal.intern(&interner),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::GoalData<RustInterner<'tcx>>> for ty::Predicate<'tcx> {
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::GoalData<RustInterner<'tcx>> {
|
||||
// FIXME(chalk): forall
|
||||
match self.bound_atom(interner.tcx).skip_binder() {
|
||||
ty::PredicateAtom::Trait(predicate, _) => {
|
||||
ty::Binder::bind(predicate).lower_into(interner)
|
||||
}
|
||||
ty::PredicateAtom::RegionOutlives(predicate) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
chalk_ir::GoalData::Quantified(
|
||||
chalk_ir::QuantifierKind::ForAll,
|
||||
chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
|
||||
chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
|
||||
a: predicate.0.lower_into(interner),
|
||||
b: predicate.1.lower_into(interner),
|
||||
}),
|
||||
))
|
||||
.intern(interner),
|
||||
),
|
||||
)
|
||||
}
|
||||
// FIXME(chalk): TypeOutlives
|
||||
ty::PredicateAtom::TypeOutlives(_predicate) => {
|
||||
chalk_ir::GoalData::All(chalk_ir::Goals::new(interner))
|
||||
}
|
||||
ty::PredicateAtom::Projection(predicate) => {
|
||||
ty::Binder::bind(predicate).lower_into(interner)
|
||||
}
|
||||
ty::PredicateAtom::WellFormed(arg) => match arg.unpack() {
|
||||
GenericArgKind::Type(ty) => match ty.kind {
|
||||
// FIXME(chalk): In Chalk, a placeholder is WellFormed if it
|
||||
// `FromEnv`. However, when we "lower" Params, we don't update
|
||||
// the environment.
|
||||
ty::Placeholder(..) => chalk_ir::GoalData::All(chalk_ir::Goals::new(interner)),
|
||||
|
||||
_ => {
|
||||
let (ty, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &ty::Binder::bind(ty));
|
||||
|
||||
chalk_ir::GoalData::Quantified(
|
||||
chalk_ir::QuantifierKind::ForAll,
|
||||
chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::WellFormed(
|
||||
chalk_ir::WellFormed::Ty(ty.lower_into(interner)),
|
||||
))
|
||||
.intern(interner),
|
||||
),
|
||||
)
|
||||
}
|
||||
},
|
||||
// FIXME(chalk): handle well formed consts
|
||||
GenericArgKind::Const(..) => {
|
||||
chalk_ir::GoalData::All(chalk_ir::Goals::new(interner))
|
||||
}
|
||||
GenericArgKind::Lifetime(lt) => bug!("unexpect well formed predicate: {:?}", lt),
|
||||
},
|
||||
|
||||
ty::PredicateAtom::ObjectSafe(t) => chalk_ir::GoalData::DomainGoal(
|
||||
chalk_ir::DomainGoal::ObjectSafe(chalk_ir::TraitId(t)),
|
||||
),
|
||||
|
||||
// FIXME(chalk): other predicates
|
||||
//
|
||||
// We can defer this, but ultimately we'll want to express
|
||||
// some of these in terms of chalk operations.
|
||||
ty::PredicateAtom::ClosureKind(..)
|
||||
| ty::PredicateAtom::Subtype(..)
|
||||
| ty::PredicateAtom::ConstEvaluatable(..)
|
||||
| ty::PredicateAtom::ConstEquate(..) => {
|
||||
chalk_ir::GoalData::All(chalk_ir::Goals::new(interner))
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::TraitRef<RustInterner<'tcx>>>
|
||||
for rustc_middle::ty::TraitRef<'tcx>
|
||||
{
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::TraitRef<RustInterner<'tcx>> {
|
||||
chalk_ir::TraitRef {
|
||||
trait_id: chalk_ir::TraitId(self.def_id),
|
||||
substitution: self.substs.lower_into(interner),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::GoalData<RustInterner<'tcx>>>
|
||||
for ty::PolyTraitPredicate<'tcx>
|
||||
{
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::GoalData<RustInterner<'tcx>> {
|
||||
let (ty, binders, _named_regions) = collect_bound_vars(interner, interner.tcx, &self);
|
||||
|
||||
chalk_ir::GoalData::Quantified(
|
||||
chalk_ir::QuantifierKind::ForAll,
|
||||
chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
|
||||
chalk_ir::WhereClause::Implemented(ty.trait_ref.lower_into(interner)),
|
||||
))
|
||||
.intern(interner),
|
||||
),
|
||||
)
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::AliasEq<RustInterner<'tcx>>>
|
||||
for rustc_middle::ty::ProjectionPredicate<'tcx>
|
||||
{
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::AliasEq<RustInterner<'tcx>> {
|
||||
chalk_ir::AliasEq {
|
||||
ty: self.ty.lower_into(interner),
|
||||
alias: self.projection_ty.lower_into(interner),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::GoalData<RustInterner<'tcx>>>
|
||||
for ty::PolyProjectionPredicate<'tcx>
|
||||
{
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::GoalData<RustInterner<'tcx>> {
|
||||
let (ty, binders, _named_regions) = collect_bound_vars(interner, interner.tcx, &self);
|
||||
|
||||
chalk_ir::GoalData::Quantified(
|
||||
chalk_ir::QuantifierKind::ForAll,
|
||||
chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::GoalData::DomainGoal(chalk_ir::DomainGoal::Holds(
|
||||
chalk_ir::WhereClause::AliasEq(ty.lower_into(interner)),
|
||||
))
|
||||
.intern(interner),
|
||||
),
|
||||
)
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::Ty<RustInterner<'tcx>>> for Ty<'tcx> {
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::Ty<RustInterner<'tcx>> {
|
||||
use chalk_ir::TyData;
|
||||
use rustc_ast as ast;
|
||||
use TyKind::*;
|
||||
|
||||
let empty = || chalk_ir::Substitution::empty(interner);
|
||||
let struct_ty =
|
||||
|def_id| chalk_ir::TypeName::Adt(chalk_ir::AdtId(interner.tcx.adt_def(def_id)));
|
||||
let apply = |name, substitution| {
|
||||
TyData::Apply(chalk_ir::ApplicationTy { name, substitution }).intern(interner)
|
||||
};
|
||||
let int = |i| apply(chalk_ir::TypeName::Scalar(chalk_ir::Scalar::Int(i)), empty());
|
||||
let uint = |i| apply(chalk_ir::TypeName::Scalar(chalk_ir::Scalar::Uint(i)), empty());
|
||||
let float = |f| apply(chalk_ir::TypeName::Scalar(chalk_ir::Scalar::Float(f)), empty());
|
||||
|
||||
match self.kind {
|
||||
Bool => apply(chalk_ir::TypeName::Scalar(chalk_ir::Scalar::Bool), empty()),
|
||||
Char => apply(chalk_ir::TypeName::Scalar(chalk_ir::Scalar::Char), empty()),
|
||||
Int(ty) => match ty {
|
||||
ast::IntTy::Isize => int(chalk_ir::IntTy::Isize),
|
||||
ast::IntTy::I8 => int(chalk_ir::IntTy::I8),
|
||||
ast::IntTy::I16 => int(chalk_ir::IntTy::I16),
|
||||
ast::IntTy::I32 => int(chalk_ir::IntTy::I32),
|
||||
ast::IntTy::I64 => int(chalk_ir::IntTy::I64),
|
||||
ast::IntTy::I128 => int(chalk_ir::IntTy::I128),
|
||||
},
|
||||
Uint(ty) => match ty {
|
||||
ast::UintTy::Usize => uint(chalk_ir::UintTy::Usize),
|
||||
ast::UintTy::U8 => uint(chalk_ir::UintTy::U8),
|
||||
ast::UintTy::U16 => uint(chalk_ir::UintTy::U16),
|
||||
ast::UintTy::U32 => uint(chalk_ir::UintTy::U32),
|
||||
ast::UintTy::U64 => uint(chalk_ir::UintTy::U64),
|
||||
ast::UintTy::U128 => uint(chalk_ir::UintTy::U128),
|
||||
},
|
||||
Float(ty) => match ty {
|
||||
ast::FloatTy::F32 => float(chalk_ir::FloatTy::F32),
|
||||
ast::FloatTy::F64 => float(chalk_ir::FloatTy::F64),
|
||||
},
|
||||
Adt(def, substs) => apply(struct_ty(def.did), substs.lower_into(interner)),
|
||||
Foreign(_def_id) => unimplemented!(),
|
||||
Str => apply(chalk_ir::TypeName::Str, empty()),
|
||||
Array(ty, len) => {
|
||||
let value = match len.val {
|
||||
ty::ConstKind::Value(val) => {
|
||||
chalk_ir::ConstValue::Concrete(chalk_ir::ConcreteConst { interned: val })
|
||||
}
|
||||
ty::ConstKind::Bound(db, bound) => {
|
||||
chalk_ir::ConstValue::BoundVar(chalk_ir::BoundVar::new(
|
||||
chalk_ir::DebruijnIndex::new(db.as_u32()),
|
||||
bound.index(),
|
||||
))
|
||||
}
|
||||
_ => unimplemented!("Const not implemented. {:?}", len.val),
|
||||
};
|
||||
apply(
|
||||
chalk_ir::TypeName::Array,
|
||||
chalk_ir::Substitution::from(
|
||||
interner,
|
||||
&[
|
||||
chalk_ir::GenericArgData::Ty(ty.lower_into(interner)).intern(interner),
|
||||
chalk_ir::GenericArgData::Const(
|
||||
chalk_ir::ConstData { ty: len.ty.lower_into(interner), value }
|
||||
.intern(interner),
|
||||
)
|
||||
.intern(interner),
|
||||
],
|
||||
),
|
||||
)
|
||||
}
|
||||
Slice(ty) => apply(
|
||||
chalk_ir::TypeName::Slice,
|
||||
chalk_ir::Substitution::from1(
|
||||
interner,
|
||||
chalk_ir::GenericArgData::Ty(ty.lower_into(interner)).intern(interner),
|
||||
),
|
||||
),
|
||||
RawPtr(ptr) => {
|
||||
let name = match ptr.mutbl {
|
||||
ast::Mutability::Mut => chalk_ir::TypeName::Raw(chalk_ir::Mutability::Mut),
|
||||
ast::Mutability::Not => chalk_ir::TypeName::Raw(chalk_ir::Mutability::Not),
|
||||
};
|
||||
apply(name, chalk_ir::Substitution::from1(interner, ptr.ty.lower_into(interner)))
|
||||
}
|
||||
Ref(region, ty, mutability) => {
|
||||
let name = match mutability {
|
||||
ast::Mutability::Mut => chalk_ir::TypeName::Ref(chalk_ir::Mutability::Mut),
|
||||
ast::Mutability::Not => chalk_ir::TypeName::Ref(chalk_ir::Mutability::Not),
|
||||
};
|
||||
apply(
|
||||
name,
|
||||
chalk_ir::Substitution::from(
|
||||
interner,
|
||||
&[
|
||||
chalk_ir::GenericArgData::Lifetime(region.lower_into(interner))
|
||||
.intern(interner),
|
||||
chalk_ir::GenericArgData::Ty(ty.lower_into(interner)).intern(interner),
|
||||
],
|
||||
),
|
||||
)
|
||||
}
|
||||
FnDef(def_id, substs) => apply(
|
||||
chalk_ir::TypeName::FnDef(chalk_ir::FnDefId(def_id)),
|
||||
substs.lower_into(interner),
|
||||
),
|
||||
FnPtr(sig) => {
|
||||
let (inputs_and_outputs, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &sig.inputs_and_output());
|
||||
TyData::Function(chalk_ir::Fn {
|
||||
num_binders: binders.len(interner),
|
||||
substitution: chalk_ir::Substitution::from(
|
||||
interner,
|
||||
inputs_and_outputs.iter().map(|ty| {
|
||||
chalk_ir::GenericArgData::Ty(ty.lower_into(interner)).intern(interner)
|
||||
}),
|
||||
),
|
||||
})
|
||||
.intern(interner)
|
||||
}
|
||||
Dynamic(predicates, region) => TyData::Dyn(chalk_ir::DynTy {
|
||||
bounds: predicates.lower_into(interner),
|
||||
lifetime: region.lower_into(interner),
|
||||
})
|
||||
.intern(interner),
|
||||
Closure(def_id, substs) => apply(
|
||||
chalk_ir::TypeName::Closure(chalk_ir::ClosureId(def_id)),
|
||||
substs.lower_into(interner),
|
||||
),
|
||||
Generator(_def_id, _substs, _) => unimplemented!(),
|
||||
GeneratorWitness(_) => unimplemented!(),
|
||||
Never => apply(chalk_ir::TypeName::Never, empty()),
|
||||
Tuple(substs) => {
|
||||
apply(chalk_ir::TypeName::Tuple(substs.len()), substs.lower_into(interner))
|
||||
}
|
||||
Projection(proj) => TyData::Alias(proj.lower_into(interner)).intern(interner),
|
||||
Opaque(def_id, substs) => {
|
||||
TyData::Alias(chalk_ir::AliasTy::Opaque(chalk_ir::OpaqueTy {
|
||||
opaque_ty_id: chalk_ir::OpaqueTyId(def_id),
|
||||
substitution: substs.lower_into(interner),
|
||||
}))
|
||||
.intern(interner)
|
||||
}
|
||||
// This should have been done eagerly prior to this, and all Params
|
||||
// should have been substituted to placeholders
|
||||
Param(_) => panic!("Lowering Param when not expected."),
|
||||
Bound(db, bound) => TyData::BoundVar(chalk_ir::BoundVar::new(
|
||||
chalk_ir::DebruijnIndex::new(db.as_u32()),
|
||||
bound.var.index(),
|
||||
))
|
||||
.intern(interner),
|
||||
Placeholder(_placeholder) => TyData::Placeholder(chalk_ir::PlaceholderIndex {
|
||||
ui: chalk_ir::UniverseIndex { counter: _placeholder.universe.as_usize() },
|
||||
idx: _placeholder.name.as_usize(),
|
||||
})
|
||||
.intern(interner),
|
||||
Infer(_infer) => unimplemented!(),
|
||||
Error(_) => apply(chalk_ir::TypeName::Error, empty()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::Lifetime<RustInterner<'tcx>>> for Region<'tcx> {
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::Lifetime<RustInterner<'tcx>> {
|
||||
use rustc_middle::ty::RegionKind::*;
|
||||
|
||||
match self {
|
||||
ReEarlyBound(_) => {
|
||||
panic!("Should have already been substituted.");
|
||||
}
|
||||
ReLateBound(db, br) => match br {
|
||||
ty::BoundRegion::BrAnon(var) => {
|
||||
chalk_ir::LifetimeData::BoundVar(chalk_ir::BoundVar::new(
|
||||
chalk_ir::DebruijnIndex::new(db.as_u32()),
|
||||
*var as usize,
|
||||
))
|
||||
.intern(interner)
|
||||
}
|
||||
ty::BoundRegion::BrNamed(_def_id, _name) => unimplemented!(),
|
||||
ty::BrEnv => unimplemented!(),
|
||||
},
|
||||
ReFree(_) => unimplemented!(),
|
||||
// FIXME(chalk): need to handle ReStatic
|
||||
ReStatic => unimplemented!(),
|
||||
ReVar(_) => unimplemented!(),
|
||||
RePlaceholder(placeholder_region) => {
|
||||
chalk_ir::LifetimeData::Placeholder(chalk_ir::PlaceholderIndex {
|
||||
ui: chalk_ir::UniverseIndex { counter: placeholder_region.universe.index() },
|
||||
idx: 0,
|
||||
})
|
||||
.intern(interner)
|
||||
}
|
||||
ReEmpty(_) => unimplemented!(),
|
||||
// FIXME(chalk): need to handle ReErased
|
||||
ReErased => unimplemented!(),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::GenericArg<RustInterner<'tcx>>> for GenericArg<'tcx> {
|
||||
fn lower_into(self, interner: &RustInterner<'tcx>) -> chalk_ir::GenericArg<RustInterner<'tcx>> {
|
||||
match self.unpack() {
|
||||
ty::subst::GenericArgKind::Type(ty) => {
|
||||
chalk_ir::GenericArgData::Ty(ty.lower_into(interner))
|
||||
}
|
||||
ty::subst::GenericArgKind::Lifetime(lifetime) => {
|
||||
chalk_ir::GenericArgData::Lifetime(lifetime.lower_into(interner))
|
||||
}
|
||||
ty::subst::GenericArgKind::Const(_) => chalk_ir::GenericArgData::Ty(
|
||||
chalk_ir::TyData::Apply(chalk_ir::ApplicationTy {
|
||||
name: chalk_ir::TypeName::Tuple(0),
|
||||
substitution: chalk_ir::Substitution::empty(interner),
|
||||
})
|
||||
.intern(interner),
|
||||
),
|
||||
}
|
||||
.intern(interner)
|
||||
}
|
||||
}
|
||||
|
||||
// We lower into an Option here since there are some predicates which Chalk
|
||||
// doesn't have a representation for yet (as a `WhereClause`), but are so common
|
||||
// that we just are accepting the unsoundness for now. The `Option` will
|
||||
// eventually be removed.
|
||||
impl<'tcx> LowerInto<'tcx, Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>>>
|
||||
for ty::Predicate<'tcx>
|
||||
{
|
||||
fn lower_into(
|
||||
self,
|
||||
interner: &RustInterner<'tcx>,
|
||||
) -> Option<chalk_ir::QuantifiedWhereClause<RustInterner<'tcx>>> {
|
||||
// FIXME(chalk): forall
|
||||
match self.bound_atom(interner.tcx).skip_binder() {
|
||||
ty::PredicateAtom::Trait(predicate, _) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
Some(chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::WhereClause::Implemented(predicate.trait_ref.lower_into(interner)),
|
||||
))
|
||||
}
|
||||
ty::PredicateAtom::RegionOutlives(predicate) => {
|
||||
let predicate = ty::Binder::bind(predicate);
|
||||
let (predicate, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &predicate);
|
||||
|
||||
Some(chalk_ir::Binders::new(
|
||||
binders,
|
||||
chalk_ir::WhereClause::LifetimeOutlives(chalk_ir::LifetimeOutlives {
|
||||
a: predicate.0.lower_into(interner),
|
||||
b: predicate.1.lower_into(interner),
|
||||
}),
|
||||
))
|
||||
}
|
||||
ty::PredicateAtom::TypeOutlives(_predicate) => None,
|
||||
ty::PredicateAtom::Projection(_predicate) => None,
|
||||
ty::PredicateAtom::WellFormed(_ty) => None,
|
||||
|
||||
ty::PredicateAtom::ObjectSafe(..)
|
||||
| ty::PredicateAtom::ClosureKind(..)
|
||||
| ty::PredicateAtom::Subtype(..)
|
||||
| ty::PredicateAtom::ConstEvaluatable(..)
|
||||
| ty::PredicateAtom::ConstEquate(..) => bug!("unexpected predicate {}", &self),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> LowerInto<'tcx, chalk_ir::Binders<chalk_ir::QuantifiedWhereClauses<RustInterner<'tcx>>>>
|
||||
for Binder<&'tcx ty::List<ty::ExistentialPredicate<'tcx>>>
|
||||
{
|
||||
fn lower_into(
|
||||
self,
|
||||
interner: &RustInterner<'tcx>,
|
||||
) -> chalk_ir::Binders<chalk_ir::QuantifiedWhereClauses<RustInterner<'tcx>>> {
|
||||
let (predicates, binders, _named_regions) =
|
||||
collect_bound_vars(interner, interner.tcx, &self);
|
||||
let where_clauses = predicates.into_iter().map(|predicate| match predicate {
|
||||
ty::ExistentialPredicate::Trait(ty::ExistentialTraitRef { def_id, substs }) => {
|
||||
chalk_ir::Binders::new(
|
||||
chalk_ir::VariableKinds::new(interner),
|
||||
chalk_ir::WhereClause::Implemented(chalk_ir::TraitRef {
|
||||
trait_id: chalk_ir::TraitId(def_id),
|
||||
substitution: substs.lower_into(interner),
|
||||
}),
|
||||
)
|
||||
}
|
||||
ty::ExistentialPredicate::Projection(_predicate) => unimplemented!(),
|
||||
ty::ExistentialPredicate::AutoTrait(def_id) => chalk_ir::Binders::new(
|
||||
chalk_ir::VariableKinds::new(interner),
|
||||
chalk_ir::WhereClause::Implemented(chalk_ir::TraitRef {
|
||||
trait_id: chalk_ir::TraitId(def_id),
|
||||
substitution: chalk_ir::Substitution::empty(interner),
|
||||
}),
|
||||
),
|
||||
});
|
||||
let value = chalk_ir::QuantifiedWhereClauses::from(interner, where_clauses);
|
||||
chalk_ir::Binders::new(binders, value)
|
||||
}
|
||||
}
|
||||
|
||||
/// To collect bound vars, we have to do two passes. In the first pass, we
|
||||
/// collect all `BoundRegion`s and `ty::Bound`s. In the second pass, we then
|
||||
/// replace `BrNamed` into `BrAnon`. The two separate passes are important,
|
||||
/// since we can only replace `BrNamed` with `BrAnon`s with indices *after* all
|
||||
/// "real" `BrAnon`s.
|
||||
///
|
||||
/// It's important to note that because of prior substitution, we may have
|
||||
/// late-bound regions, even outside of fn contexts, since this is the best way
|
||||
/// to prep types for chalk lowering.
|
||||
crate fn collect_bound_vars<'a, 'tcx, T: TypeFoldable<'tcx>>(
|
||||
interner: &RustInterner<'tcx>,
|
||||
tcx: TyCtxt<'tcx>,
|
||||
ty: &'a Binder<T>,
|
||||
) -> (T, chalk_ir::VariableKinds<RustInterner<'tcx>>, BTreeMap<DefId, u32>) {
|
||||
let mut bound_vars_collector = BoundVarsCollector::new();
|
||||
ty.as_ref().skip_binder().visit_with(&mut bound_vars_collector);
|
||||
let mut parameters = bound_vars_collector.parameters;
|
||||
let named_parameters: BTreeMap<DefId, u32> = bound_vars_collector
|
||||
.named_parameters
|
||||
.into_iter()
|
||||
.enumerate()
|
||||
.map(|(i, def_id)| (def_id, (i + parameters.len()) as u32))
|
||||
.collect();
|
||||
|
||||
let mut bound_var_substitutor = NamedBoundVarSubstitutor::new(tcx, &named_parameters);
|
||||
let new_ty = ty.as_ref().skip_binder().fold_with(&mut bound_var_substitutor);
|
||||
|
||||
for var in named_parameters.values() {
|
||||
parameters.insert(*var, chalk_ir::VariableKind::Lifetime);
|
||||
}
|
||||
|
||||
(0..parameters.len()).for_each(|i| {
|
||||
parameters
|
||||
.get(&(i as u32))
|
||||
.or_else(|| bug!("Skipped bound var index: ty={:?}, parameters={:?}", ty, parameters));
|
||||
});
|
||||
|
||||
let binders = chalk_ir::VariableKinds::from(interner, parameters.into_iter().map(|(_, v)| v));
|
||||
|
||||
(new_ty, binders, named_parameters)
|
||||
}
|
||||
|
||||
crate struct BoundVarsCollector<'tcx> {
|
||||
binder_index: ty::DebruijnIndex,
|
||||
crate parameters: BTreeMap<u32, chalk_ir::VariableKind<RustInterner<'tcx>>>,
|
||||
crate named_parameters: Vec<DefId>,
|
||||
}
|
||||
|
||||
impl<'tcx> BoundVarsCollector<'tcx> {
|
||||
crate fn new() -> Self {
|
||||
BoundVarsCollector {
|
||||
binder_index: ty::INNERMOST,
|
||||
parameters: BTreeMap::new(),
|
||||
named_parameters: vec![],
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> TypeVisitor<'tcx> for BoundVarsCollector<'tcx> {
|
||||
fn visit_binder<T: TypeFoldable<'tcx>>(&mut self, t: &Binder<T>) -> bool {
|
||||
self.binder_index.shift_in(1);
|
||||
let result = t.super_visit_with(self);
|
||||
self.binder_index.shift_out(1);
|
||||
result
|
||||
}
|
||||
|
||||
fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
|
||||
match t.kind {
|
||||
ty::Bound(debruijn, bound_ty) if debruijn == self.binder_index => {
|
||||
match self.parameters.entry(bound_ty.var.as_u32()) {
|
||||
Entry::Vacant(entry) => {
|
||||
entry.insert(chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General));
|
||||
}
|
||||
Entry::Occupied(entry) => match entry.get() {
|
||||
chalk_ir::VariableKind::Ty(_) => {}
|
||||
_ => panic!(),
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
_ => (),
|
||||
};
|
||||
|
||||
t.super_visit_with(self)
|
||||
}
|
||||
|
||||
fn visit_region(&mut self, r: Region<'tcx>) -> bool {
|
||||
match r {
|
||||
ty::ReLateBound(index, br) if *index == self.binder_index => match br {
|
||||
ty::BoundRegion::BrNamed(def_id, _name) => {
|
||||
if self.named_parameters.iter().find(|d| *d == def_id).is_none() {
|
||||
self.named_parameters.push(*def_id);
|
||||
}
|
||||
}
|
||||
|
||||
ty::BoundRegion::BrAnon(var) => match self.parameters.entry(*var) {
|
||||
Entry::Vacant(entry) => {
|
||||
entry.insert(chalk_ir::VariableKind::Lifetime);
|
||||
}
|
||||
Entry::Occupied(entry) => match entry.get() {
|
||||
chalk_ir::VariableKind::Lifetime => {}
|
||||
_ => panic!(),
|
||||
},
|
||||
},
|
||||
|
||||
ty::BrEnv => unimplemented!(),
|
||||
},
|
||||
|
||||
ty::ReEarlyBound(_re) => {
|
||||
// FIXME(chalk): jackh726 - I think we should always have already
|
||||
// substituted away `ReEarlyBound`s for `ReLateBound`s, but need to confirm.
|
||||
unimplemented!();
|
||||
}
|
||||
|
||||
_ => (),
|
||||
};
|
||||
|
||||
r.super_visit_with(self)
|
||||
}
|
||||
}
|
||||
|
||||
/// This is used to replace `BoundRegion::BrNamed` with `BoundRegion::BrAnon`.
|
||||
/// Note: we assume that we will always have room for more bound vars. (i.e. we
|
||||
/// won't ever hit the `u32` limit in `BrAnon`s).
|
||||
struct NamedBoundVarSubstitutor<'a, 'tcx> {
|
||||
tcx: TyCtxt<'tcx>,
|
||||
binder_index: ty::DebruijnIndex,
|
||||
named_parameters: &'a BTreeMap<DefId, u32>,
|
||||
}
|
||||
|
||||
impl<'a, 'tcx> NamedBoundVarSubstitutor<'a, 'tcx> {
|
||||
fn new(tcx: TyCtxt<'tcx>, named_parameters: &'a BTreeMap<DefId, u32>) -> Self {
|
||||
NamedBoundVarSubstitutor { tcx, binder_index: ty::INNERMOST, named_parameters }
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a, 'tcx> TypeFolder<'tcx> for NamedBoundVarSubstitutor<'a, 'tcx> {
|
||||
fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
|
||||
self.tcx
|
||||
}
|
||||
|
||||
fn fold_binder<T: TypeFoldable<'tcx>>(&mut self, t: &Binder<T>) -> Binder<T> {
|
||||
self.binder_index.shift_in(1);
|
||||
let result = t.super_fold_with(self);
|
||||
self.binder_index.shift_out(1);
|
||||
result
|
||||
}
|
||||
|
||||
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
|
||||
t.super_fold_with(self)
|
||||
}
|
||||
|
||||
fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx> {
|
||||
match r {
|
||||
ty::ReLateBound(index, br) if *index == self.binder_index => match br {
|
||||
ty::BoundRegion::BrNamed(def_id, _name) => {
|
||||
match self.named_parameters.get(def_id) {
|
||||
Some(idx) => {
|
||||
return self.tcx.mk_region(RegionKind::ReLateBound(
|
||||
*index,
|
||||
BoundRegion::BrAnon(*idx),
|
||||
));
|
||||
}
|
||||
None => panic!("Missing `BrNamed`."),
|
||||
}
|
||||
}
|
||||
ty::BrEnv => unimplemented!(),
|
||||
ty::BoundRegion::BrAnon(_) => {}
|
||||
},
|
||||
_ => (),
|
||||
};
|
||||
|
||||
r.super_fold_with(self)
|
||||
}
|
||||
}
|
||||
|
||||
/// Used to substitute `Param`s with placeholders. We do this since Chalk
|
||||
/// have a notion of `Param`s.
|
||||
crate struct ParamsSubstitutor<'tcx> {
|
||||
tcx: TyCtxt<'tcx>,
|
||||
binder_index: ty::DebruijnIndex,
|
||||
list: Vec<rustc_middle::ty::ParamTy>,
|
||||
crate params: rustc_data_structures::fx::FxHashMap<usize, rustc_middle::ty::ParamTy>,
|
||||
crate named_regions: BTreeMap<DefId, u32>,
|
||||
}
|
||||
|
||||
impl<'tcx> ParamsSubstitutor<'tcx> {
|
||||
crate fn new(tcx: TyCtxt<'tcx>) -> Self {
|
||||
ParamsSubstitutor {
|
||||
tcx,
|
||||
binder_index: ty::INNERMOST,
|
||||
list: vec![],
|
||||
params: rustc_data_structures::fx::FxHashMap::default(),
|
||||
named_regions: BTreeMap::default(),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> TypeFolder<'tcx> for ParamsSubstitutor<'tcx> {
|
||||
fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
|
||||
self.tcx
|
||||
}
|
||||
|
||||
fn fold_binder<T: TypeFoldable<'tcx>>(&mut self, t: &Binder<T>) -> Binder<T> {
|
||||
self.binder_index.shift_in(1);
|
||||
let result = t.super_fold_with(self);
|
||||
self.binder_index.shift_out(1);
|
||||
result
|
||||
}
|
||||
|
||||
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
|
||||
match t.kind {
|
||||
// FIXME(chalk): currently we convert params to placeholders starting at
|
||||
// index `0`. To support placeholders, we'll actually need to do a
|
||||
// first pass to collect placeholders. Then we can insert params after.
|
||||
ty::Placeholder(_) => unimplemented!(),
|
||||
ty::Param(param) => match self.list.iter().position(|r| r == ¶m) {
|
||||
Some(_idx) => self.tcx.mk_ty(ty::Placeholder(ty::PlaceholderType {
|
||||
universe: ty::UniverseIndex::from_usize(0),
|
||||
name: ty::BoundVar::from_usize(_idx),
|
||||
})),
|
||||
None => {
|
||||
self.list.push(param);
|
||||
let idx = self.list.len() - 1;
|
||||
self.params.insert(idx, param);
|
||||
self.tcx.mk_ty(ty::Placeholder(ty::PlaceholderType {
|
||||
universe: ty::UniverseIndex::from_usize(0),
|
||||
name: ty::BoundVar::from_usize(idx),
|
||||
}))
|
||||
}
|
||||
},
|
||||
|
||||
_ => t.super_fold_with(self),
|
||||
}
|
||||
}
|
||||
|
||||
fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx> {
|
||||
match r {
|
||||
// FIXME(chalk) - jackh726 - this currently isn't hit in any tests.
|
||||
// This covers any region variables in a goal, right?
|
||||
ty::ReEarlyBound(_re) => match self.named_regions.get(&_re.def_id) {
|
||||
Some(idx) => self.tcx.mk_region(RegionKind::ReLateBound(
|
||||
self.binder_index,
|
||||
BoundRegion::BrAnon(*idx),
|
||||
)),
|
||||
None => {
|
||||
let idx = self.named_regions.len() as u32;
|
||||
self.named_regions.insert(_re.def_id, idx);
|
||||
self.tcx.mk_region(RegionKind::ReLateBound(
|
||||
self.binder_index,
|
||||
BoundRegion::BrAnon(idx),
|
||||
))
|
||||
}
|
||||
},
|
||||
|
||||
_ => r.super_fold_with(self),
|
||||
}
|
||||
}
|
||||
}
|
||||
229
compiler/rustc_traits/src/chalk/mod.rs
Normal file
229
compiler/rustc_traits/src/chalk/mod.rs
Normal file
|
|
@ -0,0 +1,229 @@
|
|||
//! Calls `chalk-solve` to solve a `ty::Predicate`
|
||||
//!
|
||||
//! In order to call `chalk-solve`, this file must convert a
|
||||
//! `ChalkCanonicalGoal` into a Chalk ucanonical goal. It then calls Chalk, and
|
||||
//! converts the answer back into rustc solution.
|
||||
|
||||
crate mod db;
|
||||
crate mod lowering;
|
||||
|
||||
use rustc_data_structures::fx::FxHashMap;
|
||||
|
||||
use rustc_index::vec::IndexVec;
|
||||
|
||||
use rustc_middle::infer::canonical::{CanonicalTyVarKind, CanonicalVarKind};
|
||||
use rustc_middle::traits::ChalkRustInterner;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::subst::GenericArg;
|
||||
use rustc_middle::ty::{
|
||||
self, Bound, BoundVar, ParamTy, Region, RegionKind, Ty, TyCtxt, TypeFoldable,
|
||||
};
|
||||
|
||||
use rustc_infer::infer::canonical::{
|
||||
Canonical, CanonicalVarValues, Certainty, QueryRegionConstraints, QueryResponse,
|
||||
};
|
||||
use rustc_infer::traits::{self, ChalkCanonicalGoal};
|
||||
|
||||
use crate::chalk::db::RustIrDatabase as ChalkRustIrDatabase;
|
||||
use crate::chalk::lowering::{LowerInto, ParamsSubstitutor};
|
||||
|
||||
use chalk_solve::Solution;
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { evaluate_goal, ..*p };
|
||||
}
|
||||
|
||||
crate fn evaluate_goal<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
obligation: ChalkCanonicalGoal<'tcx>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, traits::query::NoSolution> {
|
||||
let interner = ChalkRustInterner { tcx };
|
||||
|
||||
// Chalk doesn't have a notion of `Params`, so instead we use placeholders.
|
||||
let mut params_substitutor = ParamsSubstitutor::new(tcx);
|
||||
let obligation = obligation.fold_with(&mut params_substitutor);
|
||||
let _params: FxHashMap<usize, ParamTy> = params_substitutor.params;
|
||||
let max_universe = obligation.max_universe.index();
|
||||
|
||||
let _lowered_goal: chalk_ir::UCanonical<
|
||||
chalk_ir::InEnvironment<chalk_ir::Goal<ChalkRustInterner<'tcx>>>,
|
||||
> = chalk_ir::UCanonical {
|
||||
canonical: chalk_ir::Canonical {
|
||||
binders: chalk_ir::CanonicalVarKinds::from(
|
||||
&interner,
|
||||
obligation.variables.iter().map(|v| match v.kind {
|
||||
CanonicalVarKind::PlaceholderTy(_ty) => unimplemented!(),
|
||||
CanonicalVarKind::PlaceholderRegion(_ui) => unimplemented!(),
|
||||
CanonicalVarKind::Ty(ty) => match ty {
|
||||
CanonicalTyVarKind::General(ui) => chalk_ir::WithKind::new(
|
||||
chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General),
|
||||
chalk_ir::UniverseIndex { counter: ui.index() },
|
||||
),
|
||||
CanonicalTyVarKind::Int => chalk_ir::WithKind::new(
|
||||
chalk_ir::VariableKind::Ty(chalk_ir::TyKind::Integer),
|
||||
chalk_ir::UniverseIndex::root(),
|
||||
),
|
||||
CanonicalTyVarKind::Float => chalk_ir::WithKind::new(
|
||||
chalk_ir::VariableKind::Ty(chalk_ir::TyKind::Float),
|
||||
chalk_ir::UniverseIndex::root(),
|
||||
),
|
||||
},
|
||||
CanonicalVarKind::Region(ui) => chalk_ir::WithKind::new(
|
||||
chalk_ir::VariableKind::Lifetime,
|
||||
chalk_ir::UniverseIndex { counter: ui.index() },
|
||||
),
|
||||
CanonicalVarKind::Const(_ui) => unimplemented!(),
|
||||
CanonicalVarKind::PlaceholderConst(_pc) => unimplemented!(),
|
||||
}),
|
||||
),
|
||||
value: obligation.value.lower_into(&interner),
|
||||
},
|
||||
universes: max_universe + 1,
|
||||
};
|
||||
|
||||
let solver_choice = chalk_solve::SolverChoice::SLG { max_size: 32, expected_answers: None };
|
||||
let mut solver = solver_choice.into_solver::<ChalkRustInterner<'tcx>>();
|
||||
|
||||
let db = ChalkRustIrDatabase { tcx, interner };
|
||||
let solution = solver.solve(&db, &_lowered_goal);
|
||||
|
||||
// Ideally, the code to convert *back* to rustc types would live close to
|
||||
// the code to convert *from* rustc types. Right now though, we don't
|
||||
// really need this and so it's really minimal.
|
||||
// Right now, we also treat a `Unique` solution the same as
|
||||
// `Ambig(Definite)`. This really isn't right.
|
||||
let make_solution = |_subst: chalk_ir::Substitution<_>| {
|
||||
let mut var_values: IndexVec<BoundVar, GenericArg<'tcx>> = IndexVec::new();
|
||||
_subst.parameters(&interner).iter().for_each(|p| {
|
||||
// FIXME(chalk): we should move this elsewhere, since this is
|
||||
// essentially inverse of lowering a `GenericArg`.
|
||||
let _data = p.data(&interner);
|
||||
match _data {
|
||||
chalk_ir::GenericArgData::Ty(_t) => {
|
||||
use chalk_ir::TyData;
|
||||
use rustc_ast as ast;
|
||||
|
||||
let _data = _t.data(&interner);
|
||||
let kind = match _data {
|
||||
TyData::Apply(_application_ty) => match _application_ty.name {
|
||||
chalk_ir::TypeName::Adt(_struct_id) => unimplemented!(),
|
||||
chalk_ir::TypeName::Scalar(scalar) => match scalar {
|
||||
chalk_ir::Scalar::Bool => ty::Bool,
|
||||
chalk_ir::Scalar::Char => ty::Char,
|
||||
chalk_ir::Scalar::Int(int_ty) => match int_ty {
|
||||
chalk_ir::IntTy::Isize => ty::Int(ast::IntTy::Isize),
|
||||
chalk_ir::IntTy::I8 => ty::Int(ast::IntTy::I8),
|
||||
chalk_ir::IntTy::I16 => ty::Int(ast::IntTy::I16),
|
||||
chalk_ir::IntTy::I32 => ty::Int(ast::IntTy::I32),
|
||||
chalk_ir::IntTy::I64 => ty::Int(ast::IntTy::I64),
|
||||
chalk_ir::IntTy::I128 => ty::Int(ast::IntTy::I128),
|
||||
},
|
||||
chalk_ir::Scalar::Uint(int_ty) => match int_ty {
|
||||
chalk_ir::UintTy::Usize => ty::Uint(ast::UintTy::Usize),
|
||||
chalk_ir::UintTy::U8 => ty::Uint(ast::UintTy::U8),
|
||||
chalk_ir::UintTy::U16 => ty::Uint(ast::UintTy::U16),
|
||||
chalk_ir::UintTy::U32 => ty::Uint(ast::UintTy::U32),
|
||||
chalk_ir::UintTy::U64 => ty::Uint(ast::UintTy::U64),
|
||||
chalk_ir::UintTy::U128 => ty::Uint(ast::UintTy::U128),
|
||||
},
|
||||
chalk_ir::Scalar::Float(float_ty) => match float_ty {
|
||||
chalk_ir::FloatTy::F32 => ty::Float(ast::FloatTy::F32),
|
||||
chalk_ir::FloatTy::F64 => ty::Float(ast::FloatTy::F64),
|
||||
},
|
||||
},
|
||||
chalk_ir::TypeName::Array => unimplemented!(),
|
||||
chalk_ir::TypeName::FnDef(_) => unimplemented!(),
|
||||
chalk_ir::TypeName::Closure(_) => unimplemented!(),
|
||||
chalk_ir::TypeName::Never => unimplemented!(),
|
||||
chalk_ir::TypeName::Tuple(_size) => unimplemented!(),
|
||||
chalk_ir::TypeName::Slice => unimplemented!(),
|
||||
chalk_ir::TypeName::Raw(_) => unimplemented!(),
|
||||
chalk_ir::TypeName::Ref(_) => unimplemented!(),
|
||||
chalk_ir::TypeName::Str => unimplemented!(),
|
||||
chalk_ir::TypeName::OpaqueType(_ty) => unimplemented!(),
|
||||
chalk_ir::TypeName::AssociatedType(_assoc_ty) => unimplemented!(),
|
||||
chalk_ir::TypeName::Error => unimplemented!(),
|
||||
},
|
||||
TyData::Placeholder(_placeholder) => {
|
||||
unimplemented!();
|
||||
}
|
||||
TyData::Alias(_alias_ty) => unimplemented!(),
|
||||
TyData::Function(_quantified_ty) => unimplemented!(),
|
||||
TyData::BoundVar(_bound) => Bound(
|
||||
ty::DebruijnIndex::from_usize(_bound.debruijn.depth() as usize),
|
||||
ty::BoundTy {
|
||||
var: ty::BoundVar::from_usize(_bound.index),
|
||||
kind: ty::BoundTyKind::Anon,
|
||||
},
|
||||
),
|
||||
TyData::InferenceVar(_, _) => unimplemented!(),
|
||||
TyData::Dyn(_) => unimplemented!(),
|
||||
};
|
||||
let _ty: Ty<'_> = tcx.mk_ty(kind);
|
||||
let _arg: GenericArg<'_> = _ty.into();
|
||||
var_values.push(_arg);
|
||||
}
|
||||
chalk_ir::GenericArgData::Lifetime(_l) => {
|
||||
let _data = _l.data(&interner);
|
||||
let _lifetime: Region<'_> = match _data {
|
||||
chalk_ir::LifetimeData::BoundVar(_var) => {
|
||||
tcx.mk_region(RegionKind::ReLateBound(
|
||||
rustc_middle::ty::DebruijnIndex::from_usize(
|
||||
_var.debruijn.depth() as usize
|
||||
),
|
||||
rustc_middle::ty::BoundRegion::BrAnon(_var.index as u32),
|
||||
))
|
||||
}
|
||||
chalk_ir::LifetimeData::InferenceVar(_var) => unimplemented!(),
|
||||
chalk_ir::LifetimeData::Placeholder(_index) => unimplemented!(),
|
||||
chalk_ir::LifetimeData::Phantom(_, _) => unimplemented!(),
|
||||
};
|
||||
let _arg: GenericArg<'_> = _lifetime.into();
|
||||
var_values.push(_arg);
|
||||
}
|
||||
chalk_ir::GenericArgData::Const(_) => unimplemented!(),
|
||||
}
|
||||
});
|
||||
let sol = Canonical {
|
||||
max_universe: ty::UniverseIndex::from_usize(0),
|
||||
variables: obligation.variables.clone(),
|
||||
value: QueryResponse {
|
||||
var_values: CanonicalVarValues { var_values },
|
||||
region_constraints: QueryRegionConstraints::default(),
|
||||
certainty: Certainty::Proven,
|
||||
value: (),
|
||||
},
|
||||
};
|
||||
&*tcx.arena.alloc(sol)
|
||||
};
|
||||
solution
|
||||
.map(|s| match s {
|
||||
Solution::Unique(_subst) => {
|
||||
// FIXME(chalk): handle constraints
|
||||
make_solution(_subst.value.subst)
|
||||
}
|
||||
Solution::Ambig(_guidance) => {
|
||||
match _guidance {
|
||||
chalk_solve::Guidance::Definite(_subst) => make_solution(_subst.value),
|
||||
chalk_solve::Guidance::Suggested(_) => unimplemented!(),
|
||||
chalk_solve::Guidance::Unknown => {
|
||||
// chalk_fulfill doesn't use the var_values here, so
|
||||
// let's just ignore that
|
||||
let sol = Canonical {
|
||||
max_universe: ty::UniverseIndex::from_usize(0),
|
||||
variables: obligation.variables.clone(),
|
||||
value: QueryResponse {
|
||||
var_values: CanonicalVarValues { var_values: IndexVec::new() }
|
||||
.make_identity(tcx),
|
||||
region_constraints: QueryRegionConstraints::default(),
|
||||
certainty: Certainty::Ambiguous,
|
||||
value: (),
|
||||
},
|
||||
};
|
||||
&*tcx.arena.alloc(sol)
|
||||
}
|
||||
}
|
||||
}
|
||||
})
|
||||
.ok_or(traits::query::NoSolution)
|
||||
}
|
||||
326
compiler/rustc_traits/src/dropck_outlives.rs
Normal file
326
compiler/rustc_traits/src/dropck_outlives.rs
Normal file
|
|
@ -0,0 +1,326 @@
|
|||
use rustc_data_structures::fx::FxHashSet;
|
||||
use rustc_hir::def_id::DefId;
|
||||
use rustc_infer::infer::canonical::{Canonical, QueryResponse};
|
||||
use rustc_infer::infer::TyCtxtInferExt;
|
||||
use rustc_infer::traits::TraitEngineExt as _;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::subst::{InternalSubsts, Subst};
|
||||
use rustc_middle::ty::{self, ParamEnvAnd, Ty, TyCtxt};
|
||||
use rustc_span::source_map::{Span, DUMMY_SP};
|
||||
use rustc_trait_selection::traits::query::dropck_outlives::trivial_dropck_outlives;
|
||||
use rustc_trait_selection::traits::query::dropck_outlives::{
|
||||
DropckOutlivesResult, DtorckConstraint,
|
||||
};
|
||||
use rustc_trait_selection::traits::query::normalize::AtExt;
|
||||
use rustc_trait_selection::traits::query::{CanonicalTyGoal, NoSolution};
|
||||
use rustc_trait_selection::traits::{
|
||||
Normalized, ObligationCause, TraitEngine, TraitEngineExt as _,
|
||||
};
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { dropck_outlives, adt_dtorck_constraint, ..*p };
|
||||
}
|
||||
|
||||
fn dropck_outlives<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonical_goal: CanonicalTyGoal<'tcx>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, DropckOutlivesResult<'tcx>>>, NoSolution> {
|
||||
debug!("dropck_outlives(goal={:#?})", canonical_goal);
|
||||
|
||||
tcx.infer_ctxt().enter_with_canonical(
|
||||
DUMMY_SP,
|
||||
&canonical_goal,
|
||||
|ref infcx, goal, canonical_inference_vars| {
|
||||
let tcx = infcx.tcx;
|
||||
let ParamEnvAnd { param_env, value: for_ty } = goal;
|
||||
|
||||
let mut result = DropckOutlivesResult { kinds: vec![], overflows: vec![] };
|
||||
|
||||
// A stack of types left to process. Each round, we pop
|
||||
// something from the stack and invoke
|
||||
// `dtorck_constraint_for_ty`. This may produce new types that
|
||||
// have to be pushed on the stack. This continues until we have explored
|
||||
// all the reachable types from the type `for_ty`.
|
||||
//
|
||||
// Example: Imagine that we have the following code:
|
||||
//
|
||||
// ```rust
|
||||
// struct A {
|
||||
// value: B,
|
||||
// children: Vec<A>,
|
||||
// }
|
||||
//
|
||||
// struct B {
|
||||
// value: u32
|
||||
// }
|
||||
//
|
||||
// fn f() {
|
||||
// let a: A = ...;
|
||||
// ..
|
||||
// } // here, `a` is dropped
|
||||
// ```
|
||||
//
|
||||
// at the point where `a` is dropped, we need to figure out
|
||||
// which types inside of `a` contain region data that may be
|
||||
// accessed by any destructors in `a`. We begin by pushing `A`
|
||||
// onto the stack, as that is the type of `a`. We will then
|
||||
// invoke `dtorck_constraint_for_ty` which will expand `A`
|
||||
// into the types of its fields `(B, Vec<A>)`. These will get
|
||||
// pushed onto the stack. Eventually, expanding `Vec<A>` will
|
||||
// lead to us trying to push `A` a second time -- to prevent
|
||||
// infinite recursion, we notice that `A` was already pushed
|
||||
// once and stop.
|
||||
let mut ty_stack = vec![(for_ty, 0)];
|
||||
|
||||
// Set used to detect infinite recursion.
|
||||
let mut ty_set = FxHashSet::default();
|
||||
|
||||
let mut fulfill_cx = TraitEngine::new(infcx.tcx);
|
||||
|
||||
let cause = ObligationCause::dummy();
|
||||
let mut constraints = DtorckConstraint::empty();
|
||||
while let Some((ty, depth)) = ty_stack.pop() {
|
||||
info!(
|
||||
"{} kinds, {} overflows, {} ty_stack",
|
||||
result.kinds.len(),
|
||||
result.overflows.len(),
|
||||
ty_stack.len()
|
||||
);
|
||||
dtorck_constraint_for_ty(tcx, DUMMY_SP, for_ty, depth, ty, &mut constraints)?;
|
||||
|
||||
// "outlives" represent types/regions that may be touched
|
||||
// by a destructor.
|
||||
result.kinds.extend(constraints.outlives.drain(..));
|
||||
result.overflows.extend(constraints.overflows.drain(..));
|
||||
|
||||
// If we have even one overflow, we should stop trying to evaluate further --
|
||||
// chances are, the subsequent overflows for this evaluation won't provide useful
|
||||
// information and will just decrease the speed at which we can emit these errors
|
||||
// (since we'll be printing for just that much longer for the often enormous types
|
||||
// that result here).
|
||||
if !result.overflows.is_empty() {
|
||||
break;
|
||||
}
|
||||
|
||||
// dtorck types are "types that will get dropped but which
|
||||
// do not themselves define a destructor", more or less. We have
|
||||
// to push them onto the stack to be expanded.
|
||||
for ty in constraints.dtorck_types.drain(..) {
|
||||
match infcx.at(&cause, param_env).normalize(&ty) {
|
||||
Ok(Normalized { value: ty, obligations }) => {
|
||||
fulfill_cx.register_predicate_obligations(infcx, obligations);
|
||||
|
||||
debug!("dropck_outlives: ty from dtorck_types = {:?}", ty);
|
||||
|
||||
match ty.kind {
|
||||
// All parameters live for the duration of the
|
||||
// function.
|
||||
ty::Param(..) => {}
|
||||
|
||||
// A projection that we couldn't resolve - it
|
||||
// might have a destructor.
|
||||
ty::Projection(..) | ty::Opaque(..) => {
|
||||
result.kinds.push(ty.into());
|
||||
}
|
||||
|
||||
_ => {
|
||||
if ty_set.insert(ty) {
|
||||
ty_stack.push((ty, depth + 1));
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// We don't actually expect to fail to normalize.
|
||||
// That implies a WF error somewhere else.
|
||||
Err(NoSolution) => {
|
||||
return Err(NoSolution);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
debug!("dropck_outlives: result = {:#?}", result);
|
||||
|
||||
infcx.make_canonicalized_query_response(
|
||||
canonical_inference_vars,
|
||||
result,
|
||||
&mut *fulfill_cx,
|
||||
)
|
||||
},
|
||||
)
|
||||
}
|
||||
|
||||
/// Returns a set of constraints that needs to be satisfied in
|
||||
/// order for `ty` to be valid for destruction.
|
||||
fn dtorck_constraint_for_ty<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
span: Span,
|
||||
for_ty: Ty<'tcx>,
|
||||
depth: usize,
|
||||
ty: Ty<'tcx>,
|
||||
constraints: &mut DtorckConstraint<'tcx>,
|
||||
) -> Result<(), NoSolution> {
|
||||
debug!("dtorck_constraint_for_ty({:?}, {:?}, {:?}, {:?})", span, for_ty, depth, ty);
|
||||
|
||||
if !tcx.sess.recursion_limit().value_within_limit(depth) {
|
||||
constraints.overflows.push(ty);
|
||||
return Ok(());
|
||||
}
|
||||
|
||||
if trivial_dropck_outlives(tcx, ty) {
|
||||
return Ok(());
|
||||
}
|
||||
|
||||
match ty.kind {
|
||||
ty::Bool
|
||||
| ty::Char
|
||||
| ty::Int(_)
|
||||
| ty::Uint(_)
|
||||
| ty::Float(_)
|
||||
| ty::Str
|
||||
| ty::Never
|
||||
| ty::Foreign(..)
|
||||
| ty::RawPtr(..)
|
||||
| ty::Ref(..)
|
||||
| ty::FnDef(..)
|
||||
| ty::FnPtr(_)
|
||||
| ty::GeneratorWitness(..) => {
|
||||
// these types never have a destructor
|
||||
}
|
||||
|
||||
ty::Array(ety, _) | ty::Slice(ety) => {
|
||||
// single-element containers, behave like their element
|
||||
rustc_data_structures::stack::ensure_sufficient_stack(|| {
|
||||
dtorck_constraint_for_ty(tcx, span, for_ty, depth + 1, ety, constraints)
|
||||
})?;
|
||||
}
|
||||
|
||||
ty::Tuple(tys) => rustc_data_structures::stack::ensure_sufficient_stack(|| {
|
||||
for ty in tys.iter() {
|
||||
dtorck_constraint_for_ty(
|
||||
tcx,
|
||||
span,
|
||||
for_ty,
|
||||
depth + 1,
|
||||
ty.expect_ty(),
|
||||
constraints,
|
||||
)?;
|
||||
}
|
||||
Ok::<_, NoSolution>(())
|
||||
})?,
|
||||
|
||||
ty::Closure(_, substs) => rustc_data_structures::stack::ensure_sufficient_stack(|| {
|
||||
for ty in substs.as_closure().upvar_tys() {
|
||||
dtorck_constraint_for_ty(tcx, span, for_ty, depth + 1, ty, constraints)?;
|
||||
}
|
||||
Ok::<_, NoSolution>(())
|
||||
})?,
|
||||
|
||||
ty::Generator(_, substs, _movability) => {
|
||||
// rust-lang/rust#49918: types can be constructed, stored
|
||||
// in the interior, and sit idle when generator yields
|
||||
// (and is subsequently dropped).
|
||||
//
|
||||
// It would be nice to descend into interior of a
|
||||
// generator to determine what effects dropping it might
|
||||
// have (by looking at any drop effects associated with
|
||||
// its interior).
|
||||
//
|
||||
// However, the interior's representation uses things like
|
||||
// GeneratorWitness that explicitly assume they are not
|
||||
// traversed in such a manner. So instead, we will
|
||||
// simplify things for now by treating all generators as
|
||||
// if they were like trait objects, where its upvars must
|
||||
// all be alive for the generator's (potential)
|
||||
// destructor.
|
||||
//
|
||||
// In particular, skipping over `_interior` is safe
|
||||
// because any side-effects from dropping `_interior` can
|
||||
// only take place through references with lifetimes
|
||||
// derived from lifetimes attached to the upvars and resume
|
||||
// argument, and we *do* incorporate those here.
|
||||
|
||||
constraints.outlives.extend(
|
||||
substs
|
||||
.as_generator()
|
||||
.upvar_tys()
|
||||
.map(|t| -> ty::subst::GenericArg<'tcx> { t.into() }),
|
||||
);
|
||||
constraints.outlives.push(substs.as_generator().resume_ty().into());
|
||||
}
|
||||
|
||||
ty::Adt(def, substs) => {
|
||||
let DtorckConstraint { dtorck_types, outlives, overflows } =
|
||||
tcx.at(span).adt_dtorck_constraint(def.did)?;
|
||||
// FIXME: we can try to recursively `dtorck_constraint_on_ty`
|
||||
// there, but that needs some way to handle cycles.
|
||||
constraints.dtorck_types.extend(dtorck_types.subst(tcx, substs));
|
||||
constraints.outlives.extend(outlives.subst(tcx, substs));
|
||||
constraints.overflows.extend(overflows.subst(tcx, substs));
|
||||
}
|
||||
|
||||
// Objects must be alive in order for their destructor
|
||||
// to be called.
|
||||
ty::Dynamic(..) => {
|
||||
constraints.outlives.push(ty.into());
|
||||
}
|
||||
|
||||
// Types that can't be resolved. Pass them forward.
|
||||
ty::Projection(..) | ty::Opaque(..) | ty::Param(..) => {
|
||||
constraints.dtorck_types.push(ty);
|
||||
}
|
||||
|
||||
ty::Placeholder(..) | ty::Bound(..) | ty::Infer(..) | ty::Error(_) => {
|
||||
// By the time this code runs, all type variables ought to
|
||||
// be fully resolved.
|
||||
return Err(NoSolution);
|
||||
}
|
||||
}
|
||||
|
||||
Ok(())
|
||||
}
|
||||
|
||||
/// Calculates the dtorck constraint for a type.
|
||||
crate fn adt_dtorck_constraint(
|
||||
tcx: TyCtxt<'_>,
|
||||
def_id: DefId,
|
||||
) -> Result<DtorckConstraint<'_>, NoSolution> {
|
||||
let def = tcx.adt_def(def_id);
|
||||
let span = tcx.def_span(def_id);
|
||||
debug!("dtorck_constraint: {:?}", def);
|
||||
|
||||
if def.is_phantom_data() {
|
||||
// The first generic parameter here is guaranteed to be a type because it's
|
||||
// `PhantomData`.
|
||||
let substs = InternalSubsts::identity_for_item(tcx, def_id);
|
||||
assert_eq!(substs.len(), 1);
|
||||
let result = DtorckConstraint {
|
||||
outlives: vec![],
|
||||
dtorck_types: vec![substs.type_at(0)],
|
||||
overflows: vec![],
|
||||
};
|
||||
debug!("dtorck_constraint: {:?} => {:?}", def, result);
|
||||
return Ok(result);
|
||||
}
|
||||
|
||||
let mut result = DtorckConstraint::empty();
|
||||
for field in def.all_fields() {
|
||||
let fty = tcx.type_of(field.did);
|
||||
dtorck_constraint_for_ty(tcx, span, fty, 0, fty, &mut result)?;
|
||||
}
|
||||
result.outlives.extend(tcx.destructor_constraints(def));
|
||||
dedup_dtorck_constraint(&mut result);
|
||||
|
||||
debug!("dtorck_constraint: {:?} => {:?}", def, result);
|
||||
|
||||
Ok(result)
|
||||
}
|
||||
|
||||
fn dedup_dtorck_constraint(c: &mut DtorckConstraint<'_>) {
|
||||
let mut outlives = FxHashSet::default();
|
||||
let mut dtorck_types = FxHashSet::default();
|
||||
|
||||
c.outlives.retain(|&val| outlives.replace(val).is_none());
|
||||
c.dtorck_types.retain(|&val| dtorck_types.replace(val).is_none());
|
||||
}
|
||||
32
compiler/rustc_traits/src/evaluate_obligation.rs
Normal file
32
compiler/rustc_traits/src/evaluate_obligation.rs
Normal file
|
|
@ -0,0 +1,32 @@
|
|||
use rustc_infer::infer::TyCtxtInferExt;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::{ParamEnvAnd, TyCtxt};
|
||||
use rustc_span::source_map::DUMMY_SP;
|
||||
use rustc_trait_selection::traits::query::CanonicalPredicateGoal;
|
||||
use rustc_trait_selection::traits::{
|
||||
EvaluationResult, Obligation, ObligationCause, OverflowError, SelectionContext, TraitQueryMode,
|
||||
};
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { evaluate_obligation, ..*p };
|
||||
}
|
||||
|
||||
fn evaluate_obligation<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonical_goal: CanonicalPredicateGoal<'tcx>,
|
||||
) -> Result<EvaluationResult, OverflowError> {
|
||||
debug!("evaluate_obligation(canonical_goal={:#?})", canonical_goal);
|
||||
tcx.infer_ctxt().enter_with_canonical(
|
||||
DUMMY_SP,
|
||||
&canonical_goal,
|
||||
|ref infcx, goal, _canonical_inference_vars| {
|
||||
debug!("evaluate_obligation: goal={:#?}", goal);
|
||||
let ParamEnvAnd { param_env, value: predicate } = goal;
|
||||
|
||||
let mut selcx = SelectionContext::with_query_mode(&infcx, TraitQueryMode::Canonical);
|
||||
let obligation = Obligation::new(ObligationCause::dummy(), param_env, predicate);
|
||||
|
||||
selcx.evaluate_root_obligation(&obligation)
|
||||
},
|
||||
)
|
||||
}
|
||||
166
compiler/rustc_traits/src/implied_outlives_bounds.rs
Normal file
166
compiler/rustc_traits/src/implied_outlives_bounds.rs
Normal file
|
|
@ -0,0 +1,166 @@
|
|||
//! Provider for the `implied_outlives_bounds` query.
|
||||
//! Do not call this query directory. See
|
||||
//! [`rustc_trait_selection::traits::query::type_op::implied_outlives_bounds`].
|
||||
|
||||
use rustc_hir as hir;
|
||||
use rustc_infer::infer::canonical::{self, Canonical};
|
||||
use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
|
||||
use rustc_infer::traits::TraitEngineExt as _;
|
||||
use rustc_middle::ty::outlives::Component;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable};
|
||||
use rustc_span::source_map::DUMMY_SP;
|
||||
use rustc_trait_selection::infer::InferCtxtBuilderExt;
|
||||
use rustc_trait_selection::traits::query::outlives_bounds::OutlivesBound;
|
||||
use rustc_trait_selection::traits::query::{CanonicalTyGoal, Fallible, NoSolution};
|
||||
use rustc_trait_selection::traits::wf;
|
||||
use rustc_trait_selection::traits::FulfillmentContext;
|
||||
use rustc_trait_selection::traits::TraitEngine;
|
||||
use smallvec::{smallvec, SmallVec};
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { implied_outlives_bounds, ..*p };
|
||||
}
|
||||
|
||||
fn implied_outlives_bounds<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
goal: CanonicalTyGoal<'tcx>,
|
||||
) -> Result<
|
||||
&'tcx Canonical<'tcx, canonical::QueryResponse<'tcx, Vec<OutlivesBound<'tcx>>>>,
|
||||
NoSolution,
|
||||
> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&goal, |infcx, _fulfill_cx, key| {
|
||||
let (param_env, ty) = key.into_parts();
|
||||
compute_implied_outlives_bounds(&infcx, param_env, ty)
|
||||
})
|
||||
}
|
||||
|
||||
fn compute_implied_outlives_bounds<'tcx>(
|
||||
infcx: &InferCtxt<'_, 'tcx>,
|
||||
param_env: ty::ParamEnv<'tcx>,
|
||||
ty: Ty<'tcx>,
|
||||
) -> Fallible<Vec<OutlivesBound<'tcx>>> {
|
||||
let tcx = infcx.tcx;
|
||||
|
||||
// Sometimes when we ask what it takes for T: WF, we get back that
|
||||
// U: WF is required; in that case, we push U onto this stack and
|
||||
// process it next. Currently (at least) these resulting
|
||||
// predicates are always guaranteed to be a subset of the original
|
||||
// type, so we need not fear non-termination.
|
||||
let mut wf_args = vec![ty.into()];
|
||||
|
||||
let mut implied_bounds = vec![];
|
||||
|
||||
let mut fulfill_cx = FulfillmentContext::new();
|
||||
|
||||
while let Some(arg) = wf_args.pop() {
|
||||
// Compute the obligations for `arg` to be well-formed. If `arg` is
|
||||
// an unresolved inference variable, just substituted an empty set
|
||||
// -- because the return type here is going to be things we *add*
|
||||
// to the environment, it's always ok for this set to be smaller
|
||||
// than the ultimate set. (Note: normally there won't be
|
||||
// unresolved inference variables here anyway, but there might be
|
||||
// during typeck under some circumstances.)
|
||||
let obligations =
|
||||
wf::obligations(infcx, param_env, hir::CRATE_HIR_ID, arg, DUMMY_SP).unwrap_or(vec![]);
|
||||
|
||||
// N.B., all of these predicates *ought* to be easily proven
|
||||
// true. In fact, their correctness is (mostly) implied by
|
||||
// other parts of the program. However, in #42552, we had
|
||||
// an annoying scenario where:
|
||||
//
|
||||
// - Some `T::Foo` gets normalized, resulting in a
|
||||
// variable `_1` and a `T: Trait<Foo=_1>` constraint
|
||||
// (not sure why it couldn't immediately get
|
||||
// solved). This result of `_1` got cached.
|
||||
// - These obligations were dropped on the floor here,
|
||||
// rather than being registered.
|
||||
// - Then later we would get a request to normalize
|
||||
// `T::Foo` which would result in `_1` being used from
|
||||
// the cache, but hence without the `T: Trait<Foo=_1>`
|
||||
// constraint. As a result, `_1` never gets resolved,
|
||||
// and we get an ICE (in dropck).
|
||||
//
|
||||
// Therefore, we register any predicates involving
|
||||
// inference variables. We restrict ourselves to those
|
||||
// involving inference variables both for efficiency and
|
||||
// to avoids duplicate errors that otherwise show up.
|
||||
fulfill_cx.register_predicate_obligations(
|
||||
infcx,
|
||||
obligations.iter().filter(|o| o.predicate.has_infer_types_or_consts()).cloned(),
|
||||
);
|
||||
|
||||
// From the full set of obligations, just filter down to the
|
||||
// region relationships.
|
||||
implied_bounds.extend(obligations.into_iter().flat_map(|obligation| {
|
||||
assert!(!obligation.has_escaping_bound_vars());
|
||||
match obligation.predicate.kind() {
|
||||
&ty::PredicateKind::ForAll(..) => vec![],
|
||||
&ty::PredicateKind::Atom(atom) => match atom {
|
||||
ty::PredicateAtom::Trait(..)
|
||||
| ty::PredicateAtom::Subtype(..)
|
||||
| ty::PredicateAtom::Projection(..)
|
||||
| ty::PredicateAtom::ClosureKind(..)
|
||||
| ty::PredicateAtom::ObjectSafe(..)
|
||||
| ty::PredicateAtom::ConstEvaluatable(..)
|
||||
| ty::PredicateAtom::ConstEquate(..) => vec![],
|
||||
ty::PredicateAtom::WellFormed(arg) => {
|
||||
wf_args.push(arg);
|
||||
vec![]
|
||||
}
|
||||
|
||||
ty::PredicateAtom::RegionOutlives(ty::OutlivesPredicate(r_a, r_b)) => {
|
||||
vec![OutlivesBound::RegionSubRegion(r_b, r_a)]
|
||||
}
|
||||
|
||||
ty::PredicateAtom::TypeOutlives(ty::OutlivesPredicate(ty_a, r_b)) => {
|
||||
let ty_a = infcx.resolve_vars_if_possible(&ty_a);
|
||||
let mut components = smallvec![];
|
||||
tcx.push_outlives_components(ty_a, &mut components);
|
||||
implied_bounds_from_components(r_b, components)
|
||||
}
|
||||
},
|
||||
}
|
||||
}));
|
||||
}
|
||||
|
||||
// Ensure that those obligations that we had to solve
|
||||
// get solved *here*.
|
||||
match fulfill_cx.select_all_or_error(infcx) {
|
||||
Ok(()) => Ok(implied_bounds),
|
||||
Err(_) => Err(NoSolution),
|
||||
}
|
||||
}
|
||||
|
||||
/// When we have an implied bound that `T: 'a`, we can further break
|
||||
/// this down to determine what relationships would have to hold for
|
||||
/// `T: 'a` to hold. We get to assume that the caller has validated
|
||||
/// those relationships.
|
||||
fn implied_bounds_from_components(
|
||||
sub_region: ty::Region<'tcx>,
|
||||
sup_components: SmallVec<[Component<'tcx>; 4]>,
|
||||
) -> Vec<OutlivesBound<'tcx>> {
|
||||
sup_components
|
||||
.into_iter()
|
||||
.filter_map(|component| {
|
||||
match component {
|
||||
Component::Region(r) => Some(OutlivesBound::RegionSubRegion(sub_region, r)),
|
||||
Component::Param(p) => Some(OutlivesBound::RegionSubParam(sub_region, p)),
|
||||
Component::Projection(p) => Some(OutlivesBound::RegionSubProjection(sub_region, p)),
|
||||
Component::EscapingProjection(_) =>
|
||||
// If the projection has escaping regions, don't
|
||||
// try to infer any implied bounds even for its
|
||||
// free components. This is conservative, because
|
||||
// the caller will still have to prove that those
|
||||
// free components outlive `sub_region`. But the
|
||||
// idea is that the WAY that the caller proves
|
||||
// that may change in the future and we want to
|
||||
// give ourselves room to get smarter here.
|
||||
{
|
||||
None
|
||||
}
|
||||
Component::UnresolvedInferenceVariable(..) => None,
|
||||
}
|
||||
})
|
||||
.collect()
|
||||
}
|
||||
33
compiler/rustc_traits/src/lib.rs
Normal file
33
compiler/rustc_traits/src/lib.rs
Normal file
|
|
@ -0,0 +1,33 @@
|
|||
//! New recursive solver modeled on Chalk's recursive solver. Most of
|
||||
//! the guts are broken up into modules; see the comments in those modules.
|
||||
|
||||
#![feature(crate_visibility_modifier)]
|
||||
#![feature(in_band_lifetimes)]
|
||||
#![feature(nll)]
|
||||
#![feature(or_patterns)]
|
||||
#![recursion_limit = "256"]
|
||||
|
||||
#[macro_use]
|
||||
extern crate tracing;
|
||||
#[macro_use]
|
||||
extern crate rustc_middle;
|
||||
|
||||
mod chalk;
|
||||
mod dropck_outlives;
|
||||
mod evaluate_obligation;
|
||||
mod implied_outlives_bounds;
|
||||
mod normalize_erasing_regions;
|
||||
mod normalize_projection_ty;
|
||||
mod type_op;
|
||||
|
||||
use rustc_middle::ty::query::Providers;
|
||||
|
||||
pub fn provide(p: &mut Providers) {
|
||||
dropck_outlives::provide(p);
|
||||
evaluate_obligation::provide(p);
|
||||
implied_outlives_bounds::provide(p);
|
||||
chalk::provide(p);
|
||||
normalize_projection_ty::provide(p);
|
||||
normalize_erasing_regions::provide(p);
|
||||
type_op::provide(p);
|
||||
}
|
||||
54
compiler/rustc_traits/src/normalize_erasing_regions.rs
Normal file
54
compiler/rustc_traits/src/normalize_erasing_regions.rs
Normal file
|
|
@ -0,0 +1,54 @@
|
|||
use rustc_infer::infer::TyCtxtInferExt;
|
||||
use rustc_middle::traits::query::NoSolution;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::subst::GenericArg;
|
||||
use rustc_middle::ty::{self, ParamEnvAnd, TyCtxt};
|
||||
use rustc_trait_selection::traits::query::normalize::AtExt;
|
||||
use rustc_trait_selection::traits::{Normalized, ObligationCause};
|
||||
use std::sync::atomic::Ordering;
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { normalize_generic_arg_after_erasing_regions, ..*p };
|
||||
}
|
||||
|
||||
fn normalize_generic_arg_after_erasing_regions<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
goal: ParamEnvAnd<'tcx, GenericArg<'tcx>>,
|
||||
) -> GenericArg<'tcx> {
|
||||
debug!("normalize_generic_arg_after_erasing_regions(goal={:#?})", goal);
|
||||
|
||||
let ParamEnvAnd { param_env, value } = goal;
|
||||
tcx.sess.perf_stats.normalize_generic_arg_after_erasing_regions.fetch_add(1, Ordering::Relaxed);
|
||||
tcx.infer_ctxt().enter(|infcx| {
|
||||
let cause = ObligationCause::dummy();
|
||||
match infcx.at(&cause, param_env).normalize(&value) {
|
||||
Ok(Normalized { value: normalized_value, obligations: normalized_obligations }) => {
|
||||
// We don't care about the `obligations`; they are
|
||||
// always only region relations, and we are about to
|
||||
// erase those anyway:
|
||||
debug_assert_eq!(
|
||||
normalized_obligations.iter().find(|p| not_outlives_predicate(&p.predicate)),
|
||||
None,
|
||||
);
|
||||
|
||||
let normalized_value = infcx.resolve_vars_if_possible(&normalized_value);
|
||||
infcx.tcx.erase_regions(&normalized_value)
|
||||
}
|
||||
Err(NoSolution) => bug!("could not fully normalize `{:?}`", value),
|
||||
}
|
||||
})
|
||||
}
|
||||
|
||||
fn not_outlives_predicate(p: &ty::Predicate<'tcx>) -> bool {
|
||||
match p.skip_binders() {
|
||||
ty::PredicateAtom::RegionOutlives(..) | ty::PredicateAtom::TypeOutlives(..) => false,
|
||||
ty::PredicateAtom::Trait(..)
|
||||
| ty::PredicateAtom::Projection(..)
|
||||
| ty::PredicateAtom::WellFormed(..)
|
||||
| ty::PredicateAtom::ObjectSafe(..)
|
||||
| ty::PredicateAtom::ClosureKind(..)
|
||||
| ty::PredicateAtom::Subtype(..)
|
||||
| ty::PredicateAtom::ConstEvaluatable(..)
|
||||
| ty::PredicateAtom::ConstEquate(..) => true,
|
||||
}
|
||||
}
|
||||
42
compiler/rustc_traits/src/normalize_projection_ty.rs
Normal file
42
compiler/rustc_traits/src/normalize_projection_ty.rs
Normal file
|
|
@ -0,0 +1,42 @@
|
|||
use rustc_infer::infer::canonical::{Canonical, QueryResponse};
|
||||
use rustc_infer::infer::TyCtxtInferExt;
|
||||
use rustc_infer::traits::TraitEngineExt as _;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::{ParamEnvAnd, TyCtxt};
|
||||
use rustc_trait_selection::infer::InferCtxtBuilderExt;
|
||||
use rustc_trait_selection::traits::query::{
|
||||
normalize::NormalizationResult, CanonicalProjectionGoal, NoSolution,
|
||||
};
|
||||
use rustc_trait_selection::traits::{self, ObligationCause, SelectionContext};
|
||||
use std::sync::atomic::Ordering;
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers { normalize_projection_ty, ..*p };
|
||||
}
|
||||
|
||||
fn normalize_projection_ty<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
goal: CanonicalProjectionGoal<'tcx>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, NormalizationResult<'tcx>>>, NoSolution> {
|
||||
debug!("normalize_provider(goal={:#?})", goal);
|
||||
|
||||
tcx.sess.perf_stats.normalize_projection_ty.fetch_add(1, Ordering::Relaxed);
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(
|
||||
&goal,
|
||||
|infcx, fulfill_cx, ParamEnvAnd { param_env, value: goal }| {
|
||||
let selcx = &mut SelectionContext::new(infcx);
|
||||
let cause = ObligationCause::dummy();
|
||||
let mut obligations = vec![];
|
||||
let answer = traits::normalize_projection_type(
|
||||
selcx,
|
||||
param_env,
|
||||
goal,
|
||||
cause,
|
||||
0,
|
||||
&mut obligations,
|
||||
);
|
||||
fulfill_cx.register_predicate_obligations(infcx, obligations);
|
||||
Ok(NormalizationResult { normalized_ty: answer })
|
||||
},
|
||||
)
|
||||
}
|
||||
246
compiler/rustc_traits/src/type_op.rs
Normal file
246
compiler/rustc_traits/src/type_op.rs
Normal file
|
|
@ -0,0 +1,246 @@
|
|||
use rustc_hir as hir;
|
||||
use rustc_hir::def_id::DefId;
|
||||
use rustc_infer::infer::at::ToTrace;
|
||||
use rustc_infer::infer::canonical::{Canonical, QueryResponse};
|
||||
use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
|
||||
use rustc_infer::traits::TraitEngineExt as _;
|
||||
use rustc_middle::ty::query::Providers;
|
||||
use rustc_middle::ty::subst::{GenericArg, Subst, UserSelfTy, UserSubsts};
|
||||
use rustc_middle::ty::{self, FnSig, Lift, PolyFnSig, Ty, TyCtxt, TypeFoldable, Variance};
|
||||
use rustc_middle::ty::{ParamEnv, ParamEnvAnd, Predicate, ToPredicate};
|
||||
use rustc_span::DUMMY_SP;
|
||||
use rustc_trait_selection::infer::InferCtxtBuilderExt;
|
||||
use rustc_trait_selection::infer::InferCtxtExt;
|
||||
use rustc_trait_selection::traits::query::normalize::AtExt;
|
||||
use rustc_trait_selection::traits::query::type_op::ascribe_user_type::AscribeUserType;
|
||||
use rustc_trait_selection::traits::query::type_op::eq::Eq;
|
||||
use rustc_trait_selection::traits::query::type_op::normalize::Normalize;
|
||||
use rustc_trait_selection::traits::query::type_op::prove_predicate::ProvePredicate;
|
||||
use rustc_trait_selection::traits::query::type_op::subtype::Subtype;
|
||||
use rustc_trait_selection::traits::query::{Fallible, NoSolution};
|
||||
use rustc_trait_selection::traits::{Normalized, Obligation, ObligationCause, TraitEngine};
|
||||
use std::fmt;
|
||||
|
||||
crate fn provide(p: &mut Providers) {
|
||||
*p = Providers {
|
||||
type_op_ascribe_user_type,
|
||||
type_op_eq,
|
||||
type_op_prove_predicate,
|
||||
type_op_subtype,
|
||||
type_op_normalize_ty,
|
||||
type_op_normalize_predicate,
|
||||
type_op_normalize_fn_sig,
|
||||
type_op_normalize_poly_fn_sig,
|
||||
..*p
|
||||
};
|
||||
}
|
||||
|
||||
fn type_op_ascribe_user_type<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, AscribeUserType<'tcx>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
|
||||
let (param_env, AscribeUserType { mir_ty, def_id, user_substs }) = key.into_parts();
|
||||
|
||||
debug!(
|
||||
"type_op_ascribe_user_type: mir_ty={:?} def_id={:?} user_substs={:?}",
|
||||
mir_ty, def_id, user_substs
|
||||
);
|
||||
|
||||
let mut cx = AscribeUserTypeCx { infcx, param_env, fulfill_cx };
|
||||
cx.relate_mir_and_user_ty(mir_ty, def_id, user_substs)?;
|
||||
|
||||
Ok(())
|
||||
})
|
||||
}
|
||||
|
||||
struct AscribeUserTypeCx<'me, 'tcx> {
|
||||
infcx: &'me InferCtxt<'me, 'tcx>,
|
||||
param_env: ParamEnv<'tcx>,
|
||||
fulfill_cx: &'me mut dyn TraitEngine<'tcx>,
|
||||
}
|
||||
|
||||
impl AscribeUserTypeCx<'me, 'tcx> {
|
||||
fn normalize<T>(&mut self, value: T) -> T
|
||||
where
|
||||
T: TypeFoldable<'tcx>,
|
||||
{
|
||||
self.infcx
|
||||
.partially_normalize_associated_types_in(
|
||||
DUMMY_SP,
|
||||
hir::CRATE_HIR_ID,
|
||||
self.param_env,
|
||||
&value,
|
||||
)
|
||||
.into_value_registering_obligations(self.infcx, self.fulfill_cx)
|
||||
}
|
||||
|
||||
fn relate<T>(&mut self, a: T, variance: Variance, b: T) -> Result<(), NoSolution>
|
||||
where
|
||||
T: ToTrace<'tcx>,
|
||||
{
|
||||
self.infcx
|
||||
.at(&ObligationCause::dummy(), self.param_env)
|
||||
.relate(a, variance, b)?
|
||||
.into_value_registering_obligations(self.infcx, self.fulfill_cx);
|
||||
Ok(())
|
||||
}
|
||||
|
||||
fn prove_predicate(&mut self, predicate: Predicate<'tcx>) {
|
||||
self.fulfill_cx.register_predicate_obligation(
|
||||
self.infcx,
|
||||
Obligation::new(ObligationCause::dummy(), self.param_env, predicate),
|
||||
);
|
||||
}
|
||||
|
||||
fn tcx(&self) -> TyCtxt<'tcx> {
|
||||
self.infcx.tcx
|
||||
}
|
||||
|
||||
fn subst<T>(&self, value: T, substs: &[GenericArg<'tcx>]) -> T
|
||||
where
|
||||
T: TypeFoldable<'tcx>,
|
||||
{
|
||||
value.subst(self.tcx(), substs)
|
||||
}
|
||||
|
||||
fn relate_mir_and_user_ty(
|
||||
&mut self,
|
||||
mir_ty: Ty<'tcx>,
|
||||
def_id: DefId,
|
||||
user_substs: UserSubsts<'tcx>,
|
||||
) -> Result<(), NoSolution> {
|
||||
let UserSubsts { user_self_ty, substs } = user_substs;
|
||||
let tcx = self.tcx();
|
||||
|
||||
let ty = tcx.type_of(def_id);
|
||||
let ty = self.subst(ty, substs);
|
||||
debug!("relate_type_and_user_type: ty of def-id is {:?}", ty);
|
||||
let ty = self.normalize(ty);
|
||||
|
||||
self.relate(mir_ty, Variance::Invariant, ty)?;
|
||||
|
||||
// Prove the predicates coming along with `def_id`.
|
||||
//
|
||||
// Also, normalize the `instantiated_predicates`
|
||||
// because otherwise we wind up with duplicate "type
|
||||
// outlives" error messages.
|
||||
let instantiated_predicates =
|
||||
self.tcx().predicates_of(def_id).instantiate(self.tcx(), substs);
|
||||
for instantiated_predicate in instantiated_predicates.predicates {
|
||||
let instantiated_predicate = self.normalize(instantiated_predicate);
|
||||
self.prove_predicate(instantiated_predicate);
|
||||
}
|
||||
|
||||
if let Some(UserSelfTy { impl_def_id, self_ty }) = user_self_ty {
|
||||
let impl_self_ty = self.tcx().type_of(impl_def_id);
|
||||
let impl_self_ty = self.subst(impl_self_ty, &substs);
|
||||
let impl_self_ty = self.normalize(impl_self_ty);
|
||||
|
||||
self.relate(self_ty, Variance::Invariant, impl_self_ty)?;
|
||||
|
||||
self.prove_predicate(
|
||||
ty::PredicateAtom::WellFormed(impl_self_ty.into()).to_predicate(self.tcx()),
|
||||
);
|
||||
}
|
||||
|
||||
// In addition to proving the predicates, we have to
|
||||
// prove that `ty` is well-formed -- this is because
|
||||
// the WF of `ty` is predicated on the substs being
|
||||
// well-formed, and we haven't proven *that*. We don't
|
||||
// want to prove the WF of types from `substs` directly because they
|
||||
// haven't been normalized.
|
||||
//
|
||||
// FIXME(nmatsakis): Well, perhaps we should normalize
|
||||
// them? This would only be relevant if some input
|
||||
// type were ill-formed but did not appear in `ty`,
|
||||
// which...could happen with normalization...
|
||||
self.prove_predicate(ty::PredicateAtom::WellFormed(ty.into()).to_predicate(self.tcx()));
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
|
||||
fn type_op_eq<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Eq<'tcx>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
|
||||
let (param_env, Eq { a, b }) = key.into_parts();
|
||||
infcx
|
||||
.at(&ObligationCause::dummy(), param_env)
|
||||
.eq(a, b)?
|
||||
.into_value_registering_obligations(infcx, fulfill_cx);
|
||||
Ok(())
|
||||
})
|
||||
}
|
||||
|
||||
fn type_op_normalize<T>(
|
||||
infcx: &InferCtxt<'_, 'tcx>,
|
||||
fulfill_cx: &mut dyn TraitEngine<'tcx>,
|
||||
key: ParamEnvAnd<'tcx, Normalize<T>>,
|
||||
) -> Fallible<T>
|
||||
where
|
||||
T: fmt::Debug + TypeFoldable<'tcx> + Lift<'tcx>,
|
||||
{
|
||||
let (param_env, Normalize { value }) = key.into_parts();
|
||||
let Normalized { value, obligations } =
|
||||
infcx.at(&ObligationCause::dummy(), param_env).normalize(&value)?;
|
||||
fulfill_cx.register_predicate_obligations(infcx, obligations);
|
||||
Ok(value)
|
||||
}
|
||||
|
||||
fn type_op_normalize_ty(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Normalize<Ty<'tcx>>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, Ty<'tcx>>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, type_op_normalize)
|
||||
}
|
||||
|
||||
fn type_op_normalize_predicate(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Normalize<Predicate<'tcx>>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, Predicate<'tcx>>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, type_op_normalize)
|
||||
}
|
||||
|
||||
fn type_op_normalize_fn_sig(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Normalize<FnSig<'tcx>>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, FnSig<'tcx>>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, type_op_normalize)
|
||||
}
|
||||
|
||||
fn type_op_normalize_poly_fn_sig(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Normalize<PolyFnSig<'tcx>>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, PolyFnSig<'tcx>>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, type_op_normalize)
|
||||
}
|
||||
|
||||
fn type_op_subtype<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, Subtype<'tcx>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
|
||||
let (param_env, Subtype { sub, sup }) = key.into_parts();
|
||||
infcx
|
||||
.at(&ObligationCause::dummy(), param_env)
|
||||
.sup(sup, sub)?
|
||||
.into_value_registering_obligations(infcx, fulfill_cx);
|
||||
Ok(())
|
||||
})
|
||||
}
|
||||
|
||||
fn type_op_prove_predicate<'tcx>(
|
||||
tcx: TyCtxt<'tcx>,
|
||||
canonicalized: Canonical<'tcx, ParamEnvAnd<'tcx, ProvePredicate<'tcx>>>,
|
||||
) -> Result<&'tcx Canonical<'tcx, QueryResponse<'tcx, ()>>, NoSolution> {
|
||||
tcx.infer_ctxt().enter_canonical_trait_query(&canonicalized, |infcx, fulfill_cx, key| {
|
||||
let (param_env, ProvePredicate { predicate }) = key.into_parts();
|
||||
fulfill_cx.register_predicate_obligation(
|
||||
infcx,
|
||||
Obligation::new(ObligationCause::dummy(), param_env, predicate),
|
||||
);
|
||||
Ok(())
|
||||
})
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue