1 //! This module contains `HashStable` implementations for various data types
2 //! from rustc::ty in no particular order.
4 use crate::ich::{Fingerprint, StableHashingContext, NodeIdHashingMode};
5 use rustc_data_structures::fx::FxHashMap;
6 use rustc_data_structures::stable_hasher::{HashStable, ToStableHashKey, StableHasher};
7 use std::cell::RefCell;
9 use crate::middle::region;
13 impl<'a, 'tcx, T> HashStable<StableHashingContext<'a>> for &'tcx ty::List<T>
15 T: HashStable<StableHashingContext<'a>>,
17 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
19 static CACHE: RefCell<FxHashMap<(usize, usize), Fingerprint>> =
20 RefCell::new(Default::default());
23 let hash = CACHE.with(|cache| {
24 let key = (self.as_ptr() as usize, self.len());
25 if let Some(&hash) = cache.borrow().get(&key) {
29 let mut hasher = StableHasher::new();
30 (&self[..]).hash_stable(hcx, &mut hasher);
32 let hash: Fingerprint = hasher.finish();
33 cache.borrow_mut().insert(key, hash);
37 hash.hash_stable(hcx, hasher);
41 impl<'a, 'tcx, T> ToStableHashKey<StableHashingContext<'a>> for &'tcx ty::List<T>
43 T: HashStable<StableHashingContext<'a>>,
45 type KeyType = Fingerprint;
48 fn to_stable_hash_key(&self, hcx: &StableHashingContext<'a>) -> Fingerprint {
49 let mut hasher = StableHasher::new();
50 let mut hcx: StableHashingContext<'a> = hcx.clone();
51 self.hash_stable(&mut hcx, &mut hasher);
56 impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ty::subst::GenericArg<'tcx> {
57 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
58 self.unpack().hash_stable(hcx, hasher);
62 impl<'a> HashStable<StableHashingContext<'a>>
64 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
65 mem::discriminant(self).hash_stable(hcx, hasher);
70 // No variant fields to hash for these ...
72 ty::ReLateBound(db, ty::BrAnon(i)) => {
73 db.hash_stable(hcx, hasher);
74 i.hash_stable(hcx, hasher);
76 ty::ReLateBound(db, ty::BrNamed(def_id, name)) => {
77 db.hash_stable(hcx, hasher);
78 def_id.hash_stable(hcx, hasher);
79 name.hash_stable(hcx, hasher);
81 ty::ReLateBound(db, ty::BrEnv) => {
82 db.hash_stable(hcx, hasher);
84 ty::ReEarlyBound(ty::EarlyBoundRegion { def_id, index, name }) => {
85 def_id.hash_stable(hcx, hasher);
86 index.hash_stable(hcx, hasher);
87 name.hash_stable(hcx, hasher);
89 ty::ReScope(scope) => {
90 scope.hash_stable(hcx, hasher);
92 ty::ReFree(ref free_region) => {
93 free_region.hash_stable(hcx, hasher);
95 ty::ReClosureBound(vid) => {
96 vid.hash_stable(hcx, hasher);
99 ty::RePlaceholder(..) => {
100 bug!("StableHasher: unexpected region {:?}", *self)
106 impl<'a> HashStable<StableHashingContext<'a>> for ty::RegionVid {
108 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
109 self.index().hash_stable(hcx, hasher);
113 impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ty::ConstVid<'tcx> {
115 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
116 self.index.hash_stable(hcx, hasher);
120 impl<'tcx> HashStable<StableHashingContext<'tcx>> for ty::BoundVar {
122 fn hash_stable(&self, hcx: &mut StableHashingContext<'tcx>, hasher: &mut StableHasher) {
123 self.index().hash_stable(hcx, hasher);
127 impl<'a, T> HashStable<StableHashingContext<'a>> for ty::Binder<T>
129 T: HashStable<StableHashingContext<'a>>,
131 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
132 self.skip_binder().hash_stable(hcx, hasher);
136 // AllocIds get resolved to whatever they point to (to be stable)
137 impl<'a> HashStable<StableHashingContext<'a>> for mir::interpret::AllocId {
138 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
139 ty::tls::with_opt(|tcx| {
140 trace!("hashing {:?}", *self);
141 let tcx = tcx.expect("can't hash AllocIds during hir lowering");
142 let alloc_kind = tcx.alloc_map.lock().get(*self);
143 alloc_kind.hash_stable(hcx, hasher);
148 // `Relocations` with default type parameters is a sorted map.
149 impl<'a, Tag> HashStable<StableHashingContext<'a>>
150 for mir::interpret::Relocations<Tag>
152 Tag: HashStable<StableHashingContext<'a>>,
154 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
155 self.len().hash_stable(hcx, hasher);
156 for reloc in self.iter() {
157 reloc.hash_stable(hcx, hasher);
162 impl_stable_hash_for!(enum ::syntax::ast::Mutability {
167 impl<'a> ToStableHashKey<StableHashingContext<'a>> for region::Scope {
168 type KeyType = region::Scope;
171 fn to_stable_hash_key(&self, _: &StableHashingContext<'a>) -> region::Scope {
176 impl<'a> HashStable<StableHashingContext<'a>> for ty::TyVid {
177 fn hash_stable(&self, _hcx: &mut StableHashingContext<'a>, _hasher: &mut StableHasher) {
178 // `TyVid` values are confined to an inference context and hence
179 // should not be hashed.
180 bug!("ty::TyKind::hash_stable() - can't hash a TyVid {:?}.", *self)
184 impl<'a> HashStable<StableHashingContext<'a>> for ty::IntVid {
185 fn hash_stable(&self, _hcx: &mut StableHashingContext<'a>, _hasher: &mut StableHasher) {
186 // `IntVid` values are confined to an inference context and hence
187 // should not be hashed.
188 bug!("ty::TyKind::hash_stable() - can't hash an IntVid {:?}.", *self)
192 impl<'a> HashStable<StableHashingContext<'a>> for ty::FloatVid {
193 fn hash_stable(&self, _hcx: &mut StableHashingContext<'a>, _hasher: &mut StableHasher) {
194 // `FloatVid` values are confined to an inference context and hence
195 // should not be hashed.
196 bug!("ty::TyKind::hash_stable() - can't hash a FloatVid {:?}.", *self)
200 impl<'a, T> HashStable<StableHashingContext<'a>> for ty::steal::Steal<T>
202 T: HashStable<StableHashingContext<'a>>,
204 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
205 self.borrow().hash_stable(hcx, hasher);
209 impl<'a> HashStable<StableHashingContext<'a>>
210 for crate::middle::privacy::AccessLevels {
211 fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
212 hcx.with_node_id_hashing_mode(NodeIdHashingMode::HashDefPath, |hcx| {
213 let crate::middle::privacy::AccessLevels {
217 map.hash_stable(hcx, hasher);