diff options
Diffstat (limited to 'crates/hir_ty/src/infer/unify.rs')
-rw-r--r-- | crates/hir_ty/src/infer/unify.rs | 66 |
1 files changed, 44 insertions, 22 deletions
diff --git a/crates/hir_ty/src/infer/unify.rs b/crates/hir_ty/src/infer/unify.rs index 1fc03c8f4..75250a369 100644 --- a/crates/hir_ty/src/infer/unify.rs +++ b/crates/hir_ty/src/infer/unify.rs | |||
@@ -2,13 +2,13 @@ | |||
2 | 2 | ||
3 | use std::borrow::Cow; | 3 | use std::borrow::Cow; |
4 | 4 | ||
5 | use chalk_ir::{FloatTy, IntTy, TyVariableKind}; | 5 | use chalk_ir::{FloatTy, IntTy, TyVariableKind, UniverseIndex, VariableKind}; |
6 | use ena::unify::{InPlaceUnificationTable, NoError, UnifyKey, UnifyValue}; | 6 | use ena::unify::{InPlaceUnificationTable, NoError, UnifyKey, UnifyValue}; |
7 | 7 | ||
8 | use super::{DomainGoal, InferenceContext}; | 8 | use super::{DomainGoal, InferenceContext}; |
9 | use crate::{ | 9 | use crate::{ |
10 | AliasEq, AliasTy, BoundVar, Canonical, DebruijnIndex, FnPointer, InEnvironment, InferenceVar, | 10 | AliasEq, AliasTy, BoundVar, Canonical, CanonicalVarKinds, DebruijnIndex, FnPointer, |
11 | Interner, Scalar, Substitution, Ty, TyKind, TypeWalk, WhereClause, | 11 | InEnvironment, InferenceVar, Interner, Scalar, Substitution, Ty, TyKind, TypeWalk, WhereClause, |
12 | }; | 12 | }; |
13 | 13 | ||
14 | impl<'a> InferenceContext<'a> { | 14 | impl<'a> InferenceContext<'a> { |
@@ -76,8 +76,17 @@ impl<'a, 'b> Canonicalizer<'a, 'b> { | |||
76 | } | 76 | } |
77 | 77 | ||
78 | fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> { | 78 | fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> { |
79 | let kinds = self.free_vars.iter().map(|&(_, k)| k).collect(); | 79 | let kinds = self |
80 | Canonicalized { value: Canonical { value: result, kinds }, free_vars: self.free_vars } | 80 | .free_vars |
81 | .iter() | ||
82 | .map(|&(_, k)| chalk_ir::WithKind::new(VariableKind::Ty(k), UniverseIndex::ROOT)); | ||
83 | Canonicalized { | ||
84 | value: Canonical { | ||
85 | value: result, | ||
86 | binders: CanonicalVarKinds::from_iter(&Interner, kinds), | ||
87 | }, | ||
88 | free_vars: self.free_vars, | ||
89 | } | ||
81 | } | 90 | } |
82 | 91 | ||
83 | pub(crate) fn canonicalize_ty(mut self, ty: Ty) -> Canonicalized<Ty> { | 92 | pub(crate) fn canonicalize_ty(mut self, ty: Ty) -> Canonicalized<Ty> { |
@@ -89,15 +98,12 @@ impl<'a, 'b> Canonicalizer<'a, 'b> { | |||
89 | mut self, | 98 | mut self, |
90 | obligation: InEnvironment<DomainGoal>, | 99 | obligation: InEnvironment<DomainGoal>, |
91 | ) -> Canonicalized<InEnvironment<DomainGoal>> { | 100 | ) -> Canonicalized<InEnvironment<DomainGoal>> { |
92 | let result = match obligation.value { | 101 | let result = match obligation.goal { |
93 | DomainGoal::Holds(wc) => { | 102 | DomainGoal::Holds(wc) => { |
94 | DomainGoal::Holds(self.do_canonicalize(wc, DebruijnIndex::INNERMOST)) | 103 | DomainGoal::Holds(self.do_canonicalize(wc, DebruijnIndex::INNERMOST)) |
95 | } | 104 | } |
96 | }; | 105 | }; |
97 | self.into_canonicalized(InEnvironment { | 106 | self.into_canonicalized(InEnvironment { goal: result, environment: obligation.environment }) |
98 | value: result, | ||
99 | environment: obligation.environment, | ||
100 | }) | ||
101 | } | 107 | } |
102 | } | 108 | } |
103 | 109 | ||
@@ -125,12 +131,19 @@ impl<T> Canonicalized<T> { | |||
125 | // the solution may contain new variables, which we need to convert to new inference vars | 131 | // the solution may contain new variables, which we need to convert to new inference vars |
126 | let new_vars = Substitution( | 132 | let new_vars = Substitution( |
127 | solution | 133 | solution |
128 | .kinds | 134 | .binders |
129 | .iter() | 135 | .iter(&Interner) |
130 | .map(|k| match k { | 136 | .map(|k| match k.kind { |
131 | TyVariableKind::General => ctx.table.new_type_var(), | 137 | VariableKind::Ty(TyVariableKind::General) => ctx.table.new_type_var(), |
132 | TyVariableKind::Integer => ctx.table.new_integer_var(), | 138 | VariableKind::Ty(TyVariableKind::Integer) => ctx.table.new_integer_var(), |
133 | TyVariableKind::Float => ctx.table.new_float_var(), | 139 | VariableKind::Ty(TyVariableKind::Float) => ctx.table.new_float_var(), |
140 | // HACK: Chalk can sometimes return new lifetime variables. We | ||
141 | // want to just skip them, but to not mess up the indices of | ||
142 | // other variables, we'll just create a new type variable in | ||
143 | // their place instead. This should not matter (we never see the | ||
144 | // actual *uses* of the lifetime variable). | ||
145 | VariableKind::Lifetime => ctx.table.new_type_var(), | ||
146 | _ => panic!("const variable in solution"), | ||
134 | }) | 147 | }) |
135 | .collect(), | 148 | .collect(), |
136 | ); | 149 | ); |
@@ -147,8 +160,8 @@ impl<T> Canonicalized<T> { | |||
147 | pub(crate) fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substitution> { | 160 | pub(crate) fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substitution> { |
148 | let mut table = InferenceTable::new(); | 161 | let mut table = InferenceTable::new(); |
149 | let vars = Substitution( | 162 | let vars = Substitution( |
150 | tys.kinds | 163 | tys.binders |
151 | .iter() | 164 | .iter(&Interner) |
152 | // we always use type vars here because we want everything to | 165 | // we always use type vars here because we want everything to |
153 | // fallback to Unknown in the end (kind of hacky, as below) | 166 | // fallback to Unknown in the end (kind of hacky, as below) |
154 | .map(|_| table.new_type_var()) | 167 | .map(|_| table.new_type_var()) |
@@ -170,7 +183,7 @@ pub(crate) fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substitution> { | |||
170 | } | 183 | } |
171 | } | 184 | } |
172 | Some( | 185 | Some( |
173 | Substitution::builder(tys.kinds.len()) | 186 | Substitution::builder(tys.binders.len(&Interner)) |
174 | .fill(vars.iter().map(|v| table.resolve_ty_completely(v.clone()))) | 187 | .fill(vars.iter().map(|v| table.resolve_ty_completely(v.clone()))) |
175 | .build(), | 188 | .build(), |
176 | ) | 189 | ) |
@@ -310,9 +323,18 @@ impl InferenceTable { | |||
310 | 323 | ||
311 | (TyKind::Placeholder(p1), TyKind::Placeholder(p2)) if *p1 == *p2 => true, | 324 | (TyKind::Placeholder(p1), TyKind::Placeholder(p2)) if *p1 == *p2 => true, |
312 | 325 | ||
313 | (TyKind::Dyn(dyn1), TyKind::Dyn(dyn2)) if dyn1.len() == dyn2.len() => { | 326 | (TyKind::Dyn(dyn1), TyKind::Dyn(dyn2)) |
314 | for (pred1, pred2) in dyn1.iter().zip(dyn2.iter()) { | 327 | if dyn1.bounds.skip_binders().interned().len() |
315 | if !self.unify_preds(pred1, pred2, depth + 1) { | 328 | == dyn2.bounds.skip_binders().interned().len() => |
329 | { | ||
330 | for (pred1, pred2) in dyn1 | ||
331 | .bounds | ||
332 | .skip_binders() | ||
333 | .interned() | ||
334 | .iter() | ||
335 | .zip(dyn2.bounds.skip_binders().interned().iter()) | ||
336 | { | ||
337 | if !self.unify_preds(pred1.skip_binders(), pred2.skip_binders(), depth + 1) { | ||
316 | return false; | 338 | return false; |
317 | } | 339 | } |
318 | } | 340 | } |