Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs')
| -rw-r--r-- | crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs | 136 |
1 files changed, 65 insertions, 71 deletions
diff --git a/crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs b/crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs index 0820006e5d..5d11525cd1 100644 --- a/crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs +++ b/crates/hir-ty/src/next_solver/infer/canonical/canonicalizer.rs @@ -1,14 +1,28 @@ +//! This module contains code to canonicalize values into a `Canonical<'db, T>`. +//! +//! For an overview of what canonicalization is and how it fits into +//! rustc, check out the [chapter in the rustc dev guide][c]. +//! +//! [c]: https://rust-lang.github.io/chalk/book/canonical_queries/canonicalization.html use rustc_hash::FxHashMap; use rustc_index::Idx; -use rustc_type_ir::inherent::{Const as _, IntoKind as _, Region as _, SliceLike, Ty as _}; use rustc_type_ir::InferTy::{self, FloatVar, IntVar, TyVar}; -use rustc_type_ir::{BoundVar, CanonicalQueryInput, CanonicalTyVarKind, DebruijnIndex, Flags, InferConst, RegionKind, TypeFlags, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt, UniverseIndex}; +use rustc_type_ir::inherent::{Const as _, IntoKind as _, Region as _, SliceLike, Ty as _}; +use rustc_type_ir::{ + BoundVar, CanonicalQueryInput, CanonicalTyVarKind, DebruijnIndex, Flags, InferConst, + RegionKind, TypeFlags, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt, + UniverseIndex, +}; use smallvec::SmallVec; use tracing::debug; use crate::next_solver::infer::InferCtxt; -use crate::next_solver::{Binder, BoundRegion, BoundRegionKind, BoundTy, Canonical, CanonicalVarKind, CanonicalVars, Const, ConstKind, DbInterner, GenericArg, ParamEnvAnd, Placeholder, Region, Ty, TyKind}; +use crate::next_solver::{ + Binder, BoundConst, BoundRegion, BoundRegionKind, BoundTy, Canonical, CanonicalVarKind, + CanonicalVars, Const, ConstKind, DbInterner, GenericArg, ParamEnvAnd, Placeholder, Region, Ty, + TyKind, +}; /// When we canonicalize a value to form a query, we wind up replacing /// various parts of it with canonical variables. This struct stores @@ -65,7 +79,7 @@ impl<'db> InferCtxt<'db> { // `param_env` because they are treated differently by trait selection. let canonical_param_env = Canonicalizer::canonicalize( param_env, - None, + self, self.interner, &CanonicalizeFreeRegionsOtherThanStatic, query_state, @@ -74,7 +88,7 @@ impl<'db> InferCtxt<'db> { let canonical = Canonicalizer::canonicalize_with_base( canonical_param_env, value, - Some(self), + self, self.interner, &CanonicalizeAllFreeRegions, query_state, @@ -115,7 +129,7 @@ impl<'db> InferCtxt<'db> { let mut query_state = OriginalQueryValues::default(); Canonicalizer::canonicalize( value, - Some(self), + self, self.interner, &CanonicalizeQueryResponse, &mut query_state, @@ -129,7 +143,7 @@ impl<'db> InferCtxt<'db> { let mut query_state = OriginalQueryValues::default(); Canonicalizer::canonicalize( value, - Some(self), + self, self.interner, &CanonicalizeUserTypeAnnotation, &mut query_state, @@ -165,7 +179,7 @@ impl CanonicalizeMode for CanonicalizeQueryResponse { canonicalizer: &mut Canonicalizer<'_, 'db>, mut r: Region<'db>, ) -> Region<'db> { - let infcx = canonicalizer.infcx.unwrap(); + let infcx = canonicalizer.infcx; if let RegionKind::ReVar(vid) = r.kind() { r = infcx @@ -180,12 +194,14 @@ impl CanonicalizeMode for CanonicalizeQueryResponse { }; match r.kind() { - RegionKind::ReLateParam(_) | RegionKind::ReErased | RegionKind::ReStatic | RegionKind::ReEarlyParam(..) | RegionKind::ReError(..) => r, + RegionKind::ReLateParam(_) + | RegionKind::ReErased + | RegionKind::ReStatic + | RegionKind::ReEarlyParam(..) + | RegionKind::ReError(..) => r, - RegionKind::RePlaceholder(placeholder) => canonicalizer.canonical_var_for_region( - CanonicalVarKind::PlaceholderRegion(placeholder), - r, - ), + RegionKind::RePlaceholder(placeholder) => canonicalizer + .canonical_var_for_region(CanonicalVarKind::PlaceholderRegion(placeholder), r), RegionKind::ReVar(vid) => { let universe = infcx @@ -194,10 +210,7 @@ impl CanonicalizeMode for CanonicalizeQueryResponse { .unwrap_region_constraints() .probe_value(vid) .unwrap_err(); - canonicalizer.canonical_var_for_region( - CanonicalVarKind::Region(universe), - r, - ) + canonicalizer.canonical_var_for_region(CanonicalVarKind::Region(universe), r) } _ => { @@ -240,7 +253,7 @@ impl CanonicalizeMode for CanonicalizeUserTypeAnnotation { RegionKind::ReVar(_) => canonicalizer.canonical_var_for_region_in_root_universe(r), RegionKind::RePlaceholder(..) | RegionKind::ReBound(..) => { // We only expect region names that the user can type. - panic!("unexpected region in query response: `{:?}`", r) + panic!("unexpected region in query response: `{r:?}`") } } } @@ -296,7 +309,7 @@ impl CanonicalizeMode for CanonicalizeFreeRegionsOtherThanStatic { struct Canonicalizer<'cx, 'db> { /// Set to `None` to disable the resolution of inference variables. - infcx: Option<&'cx InferCtxt<'db>>, + infcx: &'cx InferCtxt<'db>, tcx: DbInterner<'db>, variables: SmallVec<[CanonicalVarKind<'db>; 8]>, query_state: &'cx mut OriginalQueryValues<'db>, @@ -350,14 +363,14 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { // We need to canonicalize the *root* of our ty var. // This is so that our canonical response correctly reflects // any equated inference vars correctly! - let root_vid = self.infcx.unwrap().root_var(vid); + let root_vid = self.infcx.root_var(vid); if root_vid != vid { t = Ty::new_var(self.tcx, root_vid); vid = root_vid; } debug!("canonical: type var found with vid {:?}", vid); - match self.infcx.unwrap().probe_ty_var(vid) { + match self.infcx.probe_ty_var(vid) { // `t` could be a float / int variable; canonicalize that instead. Ok(t) => { debug!("(resolved to {:?})", t); @@ -380,29 +393,25 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { } TyKind::Infer(IntVar(vid)) => { - let nt = self.infcx.unwrap().opportunistic_resolve_int_var(vid); + let nt = self.infcx.opportunistic_resolve_int_var(vid); if nt != t { - return self.fold_ty(nt); + self.fold_ty(nt) } else { - self.canonicalize_ty_var( - CanonicalVarKind::Ty(CanonicalTyVarKind::Int), - t, - ) + self.canonicalize_ty_var(CanonicalVarKind::Ty(CanonicalTyVarKind::Int), t) } } TyKind::Infer(FloatVar(vid)) => { - let nt = self.infcx.unwrap().opportunistic_resolve_float_var(vid); + let nt = self.infcx.opportunistic_resolve_float_var(vid); if nt != t { - return self.fold_ty(nt); + self.fold_ty(nt) } else { - self.canonicalize_ty_var( - CanonicalVarKind::Ty(CanonicalTyVarKind::Float), - t, - ) + self.canonicalize_ty_var(CanonicalVarKind::Ty(CanonicalTyVarKind::Float), t) } } - TyKind::Infer(InferTy::FreshTy(_) | InferTy::FreshIntTy(_) | InferTy::FreshFloatTy(_)) => { + TyKind::Infer( + InferTy::FreshTy(_) | InferTy::FreshIntTy(_) | InferTy::FreshFloatTy(_), + ) => { panic!("encountered a fresh type during canonicalization") } @@ -410,10 +419,7 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { if !self.canonicalize_mode.preserve_universes() { placeholder.universe = UniverseIndex::ROOT; } - self.canonicalize_ty_var( - CanonicalVarKind::PlaceholderTy(placeholder), - t, - ) + self.canonicalize_ty_var(CanonicalVarKind::PlaceholderTy(placeholder), t) } TyKind::Bound(debruijn, _) => { @@ -465,14 +471,14 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { // We need to canonicalize the *root* of our const var. // This is so that our canonical response correctly reflects // any equated inference vars correctly! - let root_vid = self.infcx.unwrap().root_const_var(vid); + let root_vid = self.infcx.root_const_var(vid); if root_vid != vid { ct = Const::new_var(self.tcx, root_vid); vid = root_vid; } debug!("canonical: const var found with vid {:?}", vid); - match self.infcx.unwrap().probe_const_var(vid) { + match self.infcx.probe_const_var(vid) { Ok(c) => { debug!("(resolved to {:?})", c); return self.fold_const(c); @@ -485,10 +491,7 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { // FIXME: perf problem described in #55921. ui = UniverseIndex::ROOT; } - return self.canonicalize_const_var( - CanonicalVarKind::Const(ui), - ct, - ); + return self.canonicalize_const_var(CanonicalVarKind::Const(ui), ct); } } } @@ -503,10 +506,8 @@ impl<'cx, 'db> TypeFolder<DbInterner<'db>> for Canonicalizer<'cx, 'db> { } } ConstKind::Placeholder(placeholder) => { - return self.canonicalize_const_var( - CanonicalVarKind::PlaceholderConst(placeholder), - ct, - ); + return self + .canonicalize_const_var(CanonicalVarKind::PlaceholderConst(placeholder), ct); } _ => {} } @@ -524,7 +525,7 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { /// `canonicalize_query` and `canonicalize_response`. fn canonicalize<V>( value: V, - infcx: Option<&InferCtxt<'db>>, + infcx: &InferCtxt<'db>, tcx: DbInterner<'db>, canonicalize_region_mode: &dyn CanonicalizeMode, query_state: &mut OriginalQueryValues<'db>, @@ -551,7 +552,7 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { fn canonicalize_with_base<U, V>( base: Canonical<'db, U>, value: V, - infcx: Option<&InferCtxt<'db>>, + infcx: &InferCtxt<'db>, tcx: DbInterner<'db>, canonicalize_region_mode: &dyn CanonicalizeMode, query_state: &mut OriginalQueryValues<'db>, @@ -596,7 +597,8 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { // anymore. debug_assert!(!out_value.has_infer() && !out_value.has_placeholders()); - let canonical_variables = CanonicalVars::new_from_iter(tcx, canonicalizer.universe_canonicalized_variables()); + let canonical_variables = + CanonicalVars::new_from_iter(tcx, canonicalizer.universe_canonicalized_variables()); let max_universe = canonical_variables .iter() @@ -690,15 +692,11 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { self.variables .iter() .map(|v| match *v { - CanonicalVarKind::Ty(CanonicalTyVarKind::Int | CanonicalTyVarKind::Float) => { - return *v; - } + CanonicalVarKind::Ty(CanonicalTyVarKind::Int | CanonicalTyVarKind::Float) => *v, CanonicalVarKind::Ty(CanonicalTyVarKind::General(u)) => { CanonicalVarKind::Ty(CanonicalTyVarKind::General(reverse_universe_map[&u])) } - CanonicalVarKind::Region(u) => { - CanonicalVarKind::Region(reverse_universe_map[&u]) - } + CanonicalVarKind::Region(u) => CanonicalVarKind::Region(reverse_universe_map[&u]), CanonicalVarKind::Const(u) => CanonicalVarKind::Const(reverse_universe_map[&u]), CanonicalVarKind::PlaceholderTy(placeholder) => { CanonicalVarKind::PlaceholderTy(Placeholder { @@ -735,14 +733,8 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { /// /// (This works because unification never fails -- and hence trait /// selection is never affected -- due to a universe mismatch.) - fn canonical_var_for_region_in_root_universe( - &mut self, - r: Region<'db>, - ) -> Region<'db> { - self.canonical_var_for_region( - CanonicalVarKind::Region(UniverseIndex::ROOT), - r, - ) + fn canonical_var_for_region_in_root_universe(&mut self, r: Region<'db>) -> Region<'db> { + self.canonical_var_for_region(CanonicalVarKind::Region(UniverseIndex::ROOT), r) } /// Creates a canonical variable (with the given `info`) @@ -762,9 +754,13 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { /// *that*. Otherwise, create a new canonical variable for /// `ty_var`. fn canonicalize_ty_var(&mut self, info: CanonicalVarKind<'db>, ty_var: Ty<'db>) -> Ty<'db> { - debug_assert!(!self.infcx.is_some_and(|infcx| ty_var != infcx.shallow_resolve(ty_var))); + debug_assert_eq!(ty_var, self.infcx.shallow_resolve(ty_var)); let var = self.canonical_var(info, ty_var.into()); - Ty::new_bound(self.tcx, self.binder_index, BoundTy { kind: crate::next_solver::BoundTyKind::Anon, var }) + Ty::new_bound( + self.tcx, + self.binder_index, + BoundTy { kind: crate::next_solver::BoundTyKind::Anon, var }, + ) } /// Given a type variable `const_var` of the given kind, first check @@ -776,10 +772,8 @@ impl<'cx, 'db> Canonicalizer<'cx, 'db> { info: CanonicalVarKind<'db>, const_var: Const<'db>, ) -> Const<'db> { - debug_assert!( - !self.infcx.is_some_and(|infcx| const_var != infcx.shallow_resolve_const(const_var)) - ); + debug_assert_eq!(const_var, self.infcx.shallow_resolve_const(const_var)); let var = self.canonical_var(info, const_var.into()); - Const::new_bound(self.tcx, self.binder_index, var) + Const::new_bound(self.tcx, self.binder_index, BoundConst { var }) } } |