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authorLukas Wirth <[email protected]>2021-03-01 11:35:11 +0000
committerLukas Wirth <[email protected]>2021-03-01 11:41:29 +0000
commit11a1f13cd1cf6da484fd4b8bfb5f72a625c2186a (patch)
treed9923bbea2a75e02b599961790952e8a9a2edf2e /crates/hir_ty/src/infer
parent4e5c49619986144f6f0b1656bed2fac30b638a26 (diff)
Being Ty::InferenceVar closes to chalk equivalent
Diffstat (limited to 'crates/hir_ty/src/infer')
-rw-r--r--crates/hir_ty/src/infer/coerce.rs8
-rw-r--r--crates/hir_ty/src/infer/expr.rs13
-rw-r--r--crates/hir_ty/src/infer/unify.rs193
3 files changed, 130 insertions, 84 deletions
diff --git a/crates/hir_ty/src/infer/coerce.rs b/crates/hir_ty/src/infer/coerce.rs
index 4cca35904..667b26a76 100644
--- a/crates/hir_ty/src/infer/coerce.rs
+++ b/crates/hir_ty/src/infer/coerce.rs
@@ -4,12 +4,13 @@
4//! 4//!
5//! See: https://doc.rust-lang.org/nomicon/coercions.html 5//! See: https://doc.rust-lang.org/nomicon/coercions.html
6 6
7use chalk_ir::TyVariableKind;
7use hir_def::{lang_item::LangItemTarget, type_ref::Mutability}; 8use hir_def::{lang_item::LangItemTarget, type_ref::Mutability};
8use test_utils::mark; 9use test_utils::mark;
9 10
10use crate::{autoderef, traits::Solution, Obligation, Substs, TraitRef, Ty}; 11use crate::{autoderef, traits::Solution, Obligation, Substs, TraitRef, Ty};
11 12
12use super::{unify::TypeVarValue, InEnvironment, InferTy, InferenceContext}; 13use super::{InEnvironment, InferenceContext};
13 14
14impl<'a> InferenceContext<'a> { 15impl<'a> InferenceContext<'a> {
15 /// Unify two types, but may coerce the first one to the second one 16 /// Unify two types, but may coerce the first one to the second one
@@ -53,9 +54,8 @@ impl<'a> InferenceContext<'a> {
53 fn coerce_inner(&mut self, mut from_ty: Ty, to_ty: &Ty) -> bool { 54 fn coerce_inner(&mut self, mut from_ty: Ty, to_ty: &Ty) -> bool {
54 match (&from_ty, to_ty) { 55 match (&from_ty, to_ty) {
55 // Never type will make type variable to fallback to Never Type instead of Unknown. 56 // Never type will make type variable to fallback to Never Type instead of Unknown.
56 (Ty::Never, Ty::Infer(InferTy::TypeVar(tv))) => { 57 (Ty::Never, Ty::InferenceVar(tv, TyVariableKind::General)) => {
57 let var = self.table.new_maybe_never_type_var(); 58 self.table.type_variable_table.set_diverging(*tv, true);
58 self.table.var_unification_table.union_value(*tv, TypeVarValue::Known(var));
59 return true; 59 return true;
60 } 60 }
61 (Ty::Never, _) => return true, 61 (Ty::Never, _) => return true,
diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index 23d4ac8ef..928ad37a3 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -3,6 +3,7 @@
3use std::iter::{repeat, repeat_with}; 3use std::iter::{repeat, repeat_with};
4use std::{mem, sync::Arc}; 4use std::{mem, sync::Arc};
5 5
6use chalk_ir::TyVariableKind;
6use hir_def::{ 7use hir_def::{
7 expr::{Array, BinaryOp, Expr, ExprId, Literal, Statement, UnaryOp}, 8 expr::{Array, BinaryOp, Expr, ExprId, Literal, Statement, UnaryOp},
8 path::{GenericArg, GenericArgs}, 9 path::{GenericArg, GenericArgs},
@@ -18,8 +19,8 @@ use crate::{
18 primitive::{self, UintTy}, 19 primitive::{self, UintTy},
19 traits::{FnTrait, InEnvironment}, 20 traits::{FnTrait, InEnvironment},
20 utils::{generics, variant_data, Generics}, 21 utils::{generics, variant_data, Generics},
21 Binders, CallableDefId, FnPointer, FnSig, InferTy, Mutability, Obligation, OpaqueTyId, Rawness, 22 Binders, CallableDefId, FnPointer, FnSig, Mutability, Obligation, OpaqueTyId, Rawness, Scalar,
22 Scalar, Substs, TraitRef, Ty, 23 Substs, TraitRef, Ty,
23}; 24};
24 25
25use super::{ 26use super::{
@@ -527,8 +528,8 @@ impl<'a> InferenceContext<'a> {
527 Ty::Scalar(Scalar::Int(_)) 528 Ty::Scalar(Scalar::Int(_))
528 | Ty::Scalar(Scalar::Uint(_)) 529 | Ty::Scalar(Scalar::Uint(_))
529 | Ty::Scalar(Scalar::Float(_)) 530 | Ty::Scalar(Scalar::Float(_))
530 | Ty::Infer(InferTy::IntVar(..)) 531 | Ty::InferenceVar(_, TyVariableKind::Integer)
531 | Ty::Infer(InferTy::FloatVar(..)) => inner_ty, 532 | Ty::InferenceVar(_, TyVariableKind::Float) => inner_ty,
532 // Otherwise we resolve via the std::ops::Neg trait 533 // Otherwise we resolve via the std::ops::Neg trait
533 _ => self 534 _ => self
534 .resolve_associated_type(inner_ty, self.resolve_ops_neg_output()), 535 .resolve_associated_type(inner_ty, self.resolve_ops_neg_output()),
@@ -540,7 +541,7 @@ impl<'a> InferenceContext<'a> {
540 Ty::Scalar(Scalar::Bool) 541 Ty::Scalar(Scalar::Bool)
541 | Ty::Scalar(Scalar::Int(_)) 542 | Ty::Scalar(Scalar::Int(_))
542 | Ty::Scalar(Scalar::Uint(_)) 543 | Ty::Scalar(Scalar::Uint(_))
543 | Ty::Infer(InferTy::IntVar(..)) => inner_ty, 544 | Ty::InferenceVar(_, TyVariableKind::Integer) => inner_ty,
544 // Otherwise we resolve via the std::ops::Not trait 545 // Otherwise we resolve via the std::ops::Not trait
545 _ => self 546 _ => self
546 .resolve_associated_type(inner_ty, self.resolve_ops_not_output()), 547 .resolve_associated_type(inner_ty, self.resolve_ops_not_output()),
@@ -761,7 +762,7 @@ impl<'a> InferenceContext<'a> {
761 // `!`). 762 // `!`).
762 if self.diverges.is_always() { 763 if self.diverges.is_always() {
763 // we don't even make an attempt at coercion 764 // we don't even make an attempt at coercion
764 self.table.new_maybe_never_type_var() 765 self.table.new_maybe_never_var()
765 } else { 766 } else {
766 self.coerce(&Ty::unit(), expected.coercion_target()); 767 self.coerce(&Ty::unit(), expected.coercion_target());
767 Ty::unit() 768 Ty::unit()
diff --git a/crates/hir_ty/src/infer/unify.rs b/crates/hir_ty/src/infer/unify.rs
index 2852ad5bf..1e9a94c04 100644
--- a/crates/hir_ty/src/infer/unify.rs
+++ b/crates/hir_ty/src/infer/unify.rs
@@ -2,14 +2,15 @@
2 2
3use std::borrow::Cow; 3use std::borrow::Cow;
4 4
5use chalk_ir::{FloatTy, IntTy, TyVariableKind};
5use ena::unify::{InPlaceUnificationTable, NoError, UnifyKey, UnifyValue}; 6use ena::unify::{InPlaceUnificationTable, NoError, UnifyKey, UnifyValue};
6 7
7use test_utils::mark; 8use test_utils::mark;
8 9
9use super::{InferenceContext, Obligation}; 10use super::{InferenceContext, Obligation};
10use crate::{ 11use crate::{
11 BoundVar, Canonical, DebruijnIndex, GenericPredicate, InEnvironment, InferTy, Scalar, Substs, 12 BoundVar, Canonical, DebruijnIndex, GenericPredicate, InEnvironment, InferenceVar, Scalar,
12 Ty, TyKind, TypeWalk, 13 Substs, Ty, TypeWalk,
13}; 14};
14 15
15impl<'a> InferenceContext<'a> { 16impl<'a> InferenceContext<'a> {
@@ -26,7 +27,7 @@ where
26 'a: 'b, 27 'a: 'b,
27{ 28{
28 ctx: &'b mut InferenceContext<'a>, 29 ctx: &'b mut InferenceContext<'a>,
29 free_vars: Vec<InferTy>, 30 free_vars: Vec<(InferenceVar, TyVariableKind)>,
30 /// A stack of type variables that is used to detect recursive types (which 31 /// A stack of type variables that is used to detect recursive types (which
31 /// are an error, but we need to protect against them to avoid stack 32 /// are an error, but we need to protect against them to avoid stack
32 /// overflows). 33 /// overflows).
@@ -36,17 +37,14 @@ where
36#[derive(Debug)] 37#[derive(Debug)]
37pub(super) struct Canonicalized<T> { 38pub(super) struct Canonicalized<T> {
38 pub(super) value: Canonical<T>, 39 pub(super) value: Canonical<T>,
39 free_vars: Vec<InferTy>, 40 free_vars: Vec<(InferenceVar, TyVariableKind)>,
40} 41}
41 42
42impl<'a, 'b> Canonicalizer<'a, 'b> 43impl<'a, 'b> Canonicalizer<'a, 'b> {
43where 44 fn add(&mut self, free_var: InferenceVar, kind: TyVariableKind) -> usize {
44 'a: 'b, 45 self.free_vars.iter().position(|&(v, _)| v == free_var).unwrap_or_else(|| {
45{
46 fn add(&mut self, free_var: InferTy) -> usize {
47 self.free_vars.iter().position(|&v| v == free_var).unwrap_or_else(|| {
48 let next_index = self.free_vars.len(); 46 let next_index = self.free_vars.len();
49 self.free_vars.push(free_var); 47 self.free_vars.push((free_var, kind));
50 next_index 48 next_index
51 }) 49 })
52 } 50 }
@@ -54,11 +52,11 @@ where
54 fn do_canonicalize<T: TypeWalk>(&mut self, t: T, binders: DebruijnIndex) -> T { 52 fn do_canonicalize<T: TypeWalk>(&mut self, t: T, binders: DebruijnIndex) -> T {
55 t.fold_binders( 53 t.fold_binders(
56 &mut |ty, binders| match ty { 54 &mut |ty, binders| match ty {
57 Ty::Infer(tv) => { 55 Ty::InferenceVar(var, kind) => {
58 let inner = tv.to_inner(); 56 let inner = var.to_inner();
59 if self.var_stack.contains(&inner) { 57 if self.var_stack.contains(&inner) {
60 // recursive type 58 // recursive type
61 return tv.fallback_value(); 59 return self.ctx.table.type_variable_table.fallback_value(var, kind);
62 } 60 }
63 if let Some(known_ty) = 61 if let Some(known_ty) =
64 self.ctx.table.var_unification_table.inlined_probe_value(inner).known() 62 self.ctx.table.var_unification_table.inlined_probe_value(inner).known()
@@ -69,13 +67,7 @@ where
69 result 67 result
70 } else { 68 } else {
71 let root = self.ctx.table.var_unification_table.find(inner); 69 let root = self.ctx.table.var_unification_table.find(inner);
72 let free_var = match tv { 70 let position = self.add(InferenceVar::from_inner(root), kind);
73 InferTy::TypeVar(_) => InferTy::TypeVar(root),
74 InferTy::IntVar(_) => InferTy::IntVar(root),
75 InferTy::FloatVar(_) => InferTy::FloatVar(root),
76 InferTy::MaybeNeverTypeVar(_) => InferTy::MaybeNeverTypeVar(root),
77 };
78 let position = self.add(free_var);
79 Ty::Bound(BoundVar::new(binders, position)) 71 Ty::Bound(BoundVar::new(binders, position))
80 } 72 }
81 } 73 }
@@ -86,19 +78,7 @@ where
86 } 78 }
87 79
88 fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> { 80 fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> {
89 let kinds = self 81 let kinds = self.free_vars.iter().map(|&(_, k)| k).collect();
90 .free_vars
91 .iter()
92 .map(|v| match v {
93 // mapping MaybeNeverTypeVar to the same kind as general ones
94 // should be fine, because as opposed to int or float type vars,
95 // they don't restrict what kind of type can go into them, they
96 // just affect fallback.
97 InferTy::TypeVar(_) | InferTy::MaybeNeverTypeVar(_) => TyKind::General,
98 InferTy::IntVar(_) => TyKind::Integer,
99 InferTy::FloatVar(_) => TyKind::Float,
100 })
101 .collect();
102 Canonicalized { value: Canonical { value: result, kinds }, free_vars: self.free_vars } 82 Canonicalized { value: Canonical { value: result, kinds }, free_vars: self.free_vars }
103 } 83 }
104 84
@@ -132,7 +112,8 @@ impl<T> Canonicalized<T> {
132 &mut |ty, binders| { 112 &mut |ty, binders| {
133 if let &mut Ty::Bound(bound) = ty { 113 if let &mut Ty::Bound(bound) = ty {
134 if bound.debruijn >= binders { 114 if bound.debruijn >= binders {
135 *ty = Ty::Infer(self.free_vars[bound.index]); 115 let (v, k) = self.free_vars[bound.index];
116 *ty = Ty::InferenceVar(v, k);
136 } 117 }
137 } 118 }
138 }, 119 },
@@ -152,18 +133,18 @@ impl<T> Canonicalized<T> {
152 .kinds 133 .kinds
153 .iter() 134 .iter()
154 .map(|k| match k { 135 .map(|k| match k {
155 TyKind::General => ctx.table.new_type_var(), 136 TyVariableKind::General => ctx.table.new_type_var(),
156 TyKind::Integer => ctx.table.new_integer_var(), 137 TyVariableKind::Integer => ctx.table.new_integer_var(),
157 TyKind::Float => ctx.table.new_float_var(), 138 TyVariableKind::Float => ctx.table.new_float_var(),
158 }) 139 })
159 .collect(), 140 .collect(),
160 ); 141 );
161 for (i, ty) in solution.value.into_iter().enumerate() { 142 for (i, ty) in solution.value.into_iter().enumerate() {
162 let var = self.free_vars[i]; 143 let (v, k) = self.free_vars[i];
163 // eagerly replace projections in the type; we may be getting types 144 // eagerly replace projections in the type; we may be getting types
164 // e.g. from where clauses where this hasn't happened yet 145 // e.g. from where clauses where this hasn't happened yet
165 let ty = ctx.normalize_associated_types_in(ty.clone().subst_bound_vars(&new_vars)); 146 let ty = ctx.normalize_associated_types_in(ty.clone().subst_bound_vars(&new_vars));
166 ctx.table.unify(&Ty::Infer(var), &ty); 147 ctx.table.unify(&Ty::InferenceVar(v, k), &ty);
167 } 148 }
168 } 149 }
169} 150}
@@ -198,31 +179,82 @@ pub(crate) fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substs> {
198} 179}
199 180
200#[derive(Clone, Debug)] 181#[derive(Clone, Debug)]
182pub(super) struct TypeVariableTable {
183 inner: Vec<TypeVariableData>,
184}
185
186impl TypeVariableTable {
187 fn push(&mut self, data: TypeVariableData) {
188 self.inner.push(data);
189 }
190
191 pub(super) fn set_diverging(&mut self, iv: InferenceVar, diverging: bool) {
192 self.inner[iv.to_inner().0 as usize].diverging = diverging;
193 }
194
195 fn is_diverging(&mut self, iv: InferenceVar) -> bool {
196 self.inner[iv.to_inner().0 as usize].diverging
197 }
198
199 fn fallback_value(&self, iv: InferenceVar, kind: TyVariableKind) -> Ty {
200 match kind {
201 _ if self.inner[iv.to_inner().0 as usize].diverging => Ty::Never,
202 TyVariableKind::General => Ty::Unknown,
203 TyVariableKind::Integer => Ty::Scalar(Scalar::Int(IntTy::I32)),
204 TyVariableKind::Float => Ty::Scalar(Scalar::Float(FloatTy::F64)),
205 }
206 }
207}
208
209#[derive(Copy, Clone, Debug)]
210pub(crate) struct TypeVariableData {
211 diverging: bool,
212}
213
214#[derive(Clone, Debug)]
201pub(crate) struct InferenceTable { 215pub(crate) struct InferenceTable {
202 pub(super) var_unification_table: InPlaceUnificationTable<TypeVarId>, 216 pub(super) var_unification_table: InPlaceUnificationTable<TypeVarId>,
217 pub(super) type_variable_table: TypeVariableTable,
203} 218}
204 219
205impl InferenceTable { 220impl InferenceTable {
206 pub(crate) fn new() -> Self { 221 pub(crate) fn new() -> Self {
207 InferenceTable { var_unification_table: InPlaceUnificationTable::new() } 222 InferenceTable {
223 var_unification_table: InPlaceUnificationTable::new(),
224 type_variable_table: TypeVariableTable { inner: Vec::new() },
225 }
208 } 226 }
209 227
210 pub(crate) fn new_type_var(&mut self) -> Ty { 228 pub(crate) fn new_type_var(&mut self) -> Ty {
211 Ty::Infer(InferTy::TypeVar(self.var_unification_table.new_key(TypeVarValue::Unknown))) 229 self.type_variable_table.push(TypeVariableData { diverging: false });
230 Ty::InferenceVar(
231 InferenceVar::from_inner(self.var_unification_table.new_key(TypeVarValue::Unknown)),
232 TyVariableKind::General,
233 )
212 } 234 }
213 235
214 pub(crate) fn new_integer_var(&mut self) -> Ty { 236 pub(crate) fn new_integer_var(&mut self) -> Ty {
215 Ty::Infer(InferTy::IntVar(self.var_unification_table.new_key(TypeVarValue::Unknown))) 237 self.type_variable_table.push(TypeVariableData { diverging: false });
238 Ty::InferenceVar(
239 InferenceVar::from_inner(self.var_unification_table.new_key(TypeVarValue::Unknown)),
240 TyVariableKind::Integer,
241 )
216 } 242 }
217 243
218 pub(crate) fn new_float_var(&mut self) -> Ty { 244 pub(crate) fn new_float_var(&mut self) -> Ty {
219 Ty::Infer(InferTy::FloatVar(self.var_unification_table.new_key(TypeVarValue::Unknown))) 245 self.type_variable_table.push(TypeVariableData { diverging: false });
246 Ty::InferenceVar(
247 InferenceVar::from_inner(self.var_unification_table.new_key(TypeVarValue::Unknown)),
248 TyVariableKind::Float,
249 )
220 } 250 }
221 251
222 pub(crate) fn new_maybe_never_type_var(&mut self) -> Ty { 252 pub(crate) fn new_maybe_never_var(&mut self) -> Ty {
223 Ty::Infer(InferTy::MaybeNeverTypeVar( 253 self.type_variable_table.push(TypeVariableData { diverging: true });
224 self.var_unification_table.new_key(TypeVarValue::Unknown), 254 Ty::InferenceVar(
225 )) 255 InferenceVar::from_inner(self.var_unification_table.new_key(TypeVarValue::Unknown)),
256 TyVariableKind::General,
257 )
226 } 258 }
227 259
228 pub(crate) fn resolve_ty_completely(&mut self, ty: Ty) -> Ty { 260 pub(crate) fn resolve_ty_completely(&mut self, ty: Ty) -> Ty {
@@ -283,33 +315,46 @@ impl InferenceTable {
283 true 315 true
284 } 316 }
285 317
286 (Ty::Infer(InferTy::TypeVar(tv1)), Ty::Infer(InferTy::TypeVar(tv2))) 318 (
287 | (Ty::Infer(InferTy::IntVar(tv1)), Ty::Infer(InferTy::IntVar(tv2))) 319 Ty::InferenceVar(tv1, TyVariableKind::General),
288 | (Ty::Infer(InferTy::FloatVar(tv1)), Ty::Infer(InferTy::FloatVar(tv2))) 320 Ty::InferenceVar(tv2, TyVariableKind::General),
321 )
289 | ( 322 | (
290 Ty::Infer(InferTy::MaybeNeverTypeVar(tv1)), 323 Ty::InferenceVar(tv1, TyVariableKind::Integer),
291 Ty::Infer(InferTy::MaybeNeverTypeVar(tv2)), 324 Ty::InferenceVar(tv2, TyVariableKind::Integer),
292 ) => { 325 )
326 | (
327 Ty::InferenceVar(tv1, TyVariableKind::Float),
328 Ty::InferenceVar(tv2, TyVariableKind::Float),
329 ) if self.type_variable_table.is_diverging(*tv1)
330 == self.type_variable_table.is_diverging(*tv2) =>
331 {
293 // both type vars are unknown since we tried to resolve them 332 // both type vars are unknown since we tried to resolve them
294 self.var_unification_table.union(*tv1, *tv2); 333 self.var_unification_table.union(tv1.to_inner(), tv2.to_inner());
295 true 334 true
296 } 335 }
297 336
298 // The order of MaybeNeverTypeVar matters here. 337 // The order of MaybeNeverTypeVar matters here.
299 // Unifying MaybeNeverTypeVar and TypeVar will let the latter become MaybeNeverTypeVar. 338 // Unifying MaybeNeverTypeVar and TypeVar will let the latter become MaybeNeverTypeVar.
300 // Unifying MaybeNeverTypeVar and other concrete type will let the former become it. 339 // Unifying MaybeNeverTypeVar and other concrete type will let the former become it.
301 (Ty::Infer(InferTy::TypeVar(tv)), other) 340 (Ty::InferenceVar(tv, TyVariableKind::General), other)
302 | (other, Ty::Infer(InferTy::TypeVar(tv))) 341 | (other, Ty::InferenceVar(tv, TyVariableKind::General))
303 | (Ty::Infer(InferTy::MaybeNeverTypeVar(tv)), other) 342 | (Ty::InferenceVar(tv, TyVariableKind::Integer), other @ Ty::Scalar(Scalar::Int(_)))
304 | (other, Ty::Infer(InferTy::MaybeNeverTypeVar(tv))) 343 | (other @ Ty::Scalar(Scalar::Int(_)), Ty::InferenceVar(tv, TyVariableKind::Integer))
305 | (Ty::Infer(InferTy::IntVar(tv)), other @ Ty::Scalar(Scalar::Int(_))) 344 | (
306 | (other @ Ty::Scalar(Scalar::Int(_)), Ty::Infer(InferTy::IntVar(tv))) 345 Ty::InferenceVar(tv, TyVariableKind::Integer),
307 | (Ty::Infer(InferTy::IntVar(tv)), other @ Ty::Scalar(Scalar::Uint(_))) 346 other @ Ty::Scalar(Scalar::Uint(_)),
308 | (other @ Ty::Scalar(Scalar::Uint(_)), Ty::Infer(InferTy::IntVar(tv))) 347 )
309 | (Ty::Infer(InferTy::FloatVar(tv)), other @ Ty::Scalar(Scalar::Float(_))) 348 | (
310 | (other @ Ty::Scalar(Scalar::Float(_)), Ty::Infer(InferTy::FloatVar(tv))) => { 349 other @ Ty::Scalar(Scalar::Uint(_)),
350 Ty::InferenceVar(tv, TyVariableKind::Integer),
351 )
352 | (Ty::InferenceVar(tv, TyVariableKind::Float), other @ Ty::Scalar(Scalar::Float(_)))
353 | (other @ Ty::Scalar(Scalar::Float(_)), Ty::InferenceVar(tv, TyVariableKind::Float)) =>
354 {
311 // the type var is unknown since we tried to resolve it 355 // the type var is unknown since we tried to resolve it
312 self.var_unification_table.union_value(*tv, TypeVarValue::Known(other.clone())); 356 self.var_unification_table
357 .union_value(tv.to_inner(), TypeVarValue::Known(other.clone()));
313 true 358 true
314 } 359 }
315 360
@@ -354,7 +399,7 @@ impl InferenceTable {
354 mark::hit!(type_var_resolves_to_int_var); 399 mark::hit!(type_var_resolves_to_int_var);
355 } 400 }
356 match &*ty { 401 match &*ty {
357 Ty::Infer(tv) => { 402 Ty::InferenceVar(tv, _) => {
358 let inner = tv.to_inner(); 403 let inner = tv.to_inner();
359 match self.var_unification_table.inlined_probe_value(inner).known() { 404 match self.var_unification_table.inlined_probe_value(inner).known() {
360 Some(known_ty) => { 405 Some(known_ty) => {
@@ -377,12 +422,12 @@ impl InferenceTable {
377 /// known type. 422 /// known type.
378 fn resolve_ty_as_possible_inner(&mut self, tv_stack: &mut Vec<TypeVarId>, ty: Ty) -> Ty { 423 fn resolve_ty_as_possible_inner(&mut self, tv_stack: &mut Vec<TypeVarId>, ty: Ty) -> Ty {
379 ty.fold(&mut |ty| match ty { 424 ty.fold(&mut |ty| match ty {
380 Ty::Infer(tv) => { 425 Ty::InferenceVar(tv, kind) => {
381 let inner = tv.to_inner(); 426 let inner = tv.to_inner();
382 if tv_stack.contains(&inner) { 427 if tv_stack.contains(&inner) {
383 mark::hit!(type_var_cycles_resolve_as_possible); 428 mark::hit!(type_var_cycles_resolve_as_possible);
384 // recursive type 429 // recursive type
385 return tv.fallback_value(); 430 return self.type_variable_table.fallback_value(tv, kind);
386 } 431 }
387 if let Some(known_ty) = 432 if let Some(known_ty) =
388 self.var_unification_table.inlined_probe_value(inner).known() 433 self.var_unification_table.inlined_probe_value(inner).known()
@@ -404,12 +449,12 @@ impl InferenceTable {
404 /// replaced by Ty::Unknown. 449 /// replaced by Ty::Unknown.
405 fn resolve_ty_completely_inner(&mut self, tv_stack: &mut Vec<TypeVarId>, ty: Ty) -> Ty { 450 fn resolve_ty_completely_inner(&mut self, tv_stack: &mut Vec<TypeVarId>, ty: Ty) -> Ty {
406 ty.fold(&mut |ty| match ty { 451 ty.fold(&mut |ty| match ty {
407 Ty::Infer(tv) => { 452 Ty::InferenceVar(tv, kind) => {
408 let inner = tv.to_inner(); 453 let inner = tv.to_inner();
409 if tv_stack.contains(&inner) { 454 if tv_stack.contains(&inner) {
410 mark::hit!(type_var_cycles_resolve_completely); 455 mark::hit!(type_var_cycles_resolve_completely);
411 // recursive type 456 // recursive type
412 return tv.fallback_value(); 457 return self.type_variable_table.fallback_value(tv, kind);
413 } 458 }
414 if let Some(known_ty) = 459 if let Some(known_ty) =
415 self.var_unification_table.inlined_probe_value(inner).known() 460 self.var_unification_table.inlined_probe_value(inner).known()
@@ -420,7 +465,7 @@ impl InferenceTable {
420 tv_stack.pop(); 465 tv_stack.pop();
421 result 466 result
422 } else { 467 } else {
423 tv.fallback_value() 468 self.type_variable_table.fallback_value(tv, kind)
424 } 469 }
425 } 470 }
426 _ => ty, 471 _ => ty,
@@ -430,7 +475,7 @@ impl InferenceTable {
430 475
431/// The ID of a type variable. 476/// The ID of a type variable.
432#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)] 477#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
433pub struct TypeVarId(pub(super) u32); 478pub(super) struct TypeVarId(pub(super) u32);
434 479
435impl UnifyKey for TypeVarId { 480impl UnifyKey for TypeVarId {
436 type Value = TypeVarValue; 481 type Value = TypeVarValue;
@@ -451,7 +496,7 @@ impl UnifyKey for TypeVarId {
451/// The value of a type variable: either we already know the type, or we don't 496/// The value of a type variable: either we already know the type, or we don't
452/// know it yet. 497/// know it yet.
453#[derive(Clone, PartialEq, Eq, Debug)] 498#[derive(Clone, PartialEq, Eq, Debug)]
454pub enum TypeVarValue { 499pub(super) enum TypeVarValue {
455 Known(Ty), 500 Known(Ty),
456 Unknown, 501 Unknown,
457} 502}