mv compiler to compiler/

compiler/rustc_hir/src/stable_hash_impls.rs

@@ -0,0 +1,167 @@
+use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
+
+use crate::hir::{
+    BodyId, Expr, ImplItem, ImplItemId, Item, ItemId, Mod, TraitItem, TraitItemId, Ty,
+    VisibilityKind,
+};
+use crate::hir_id::{HirId, ItemLocalId};
+use rustc_span::def_id::{DefPathHash, LocalDefId};
+
+/// Requirements for a `StableHashingContext` to be used in this crate.
+/// This is a hack to allow using the `HashStable_Generic` derive macro
+/// instead of implementing everything in librustc_middle.
+pub trait HashStableContext:
+    rustc_ast::HashStableContext + rustc_target::HashStableContext
+{
+    fn hash_hir_id(&mut self, _: HirId, hasher: &mut StableHasher);
+    fn hash_body_id(&mut self, _: BodyId, hasher: &mut StableHasher);
+    fn hash_reference_to_item(&mut self, _: HirId, hasher: &mut StableHasher);
+    fn hash_hir_mod(&mut self, _: &Mod<'_>, hasher: &mut StableHasher);
+    fn hash_hir_expr(&mut self, _: &Expr<'_>, hasher: &mut StableHasher);
+    fn hash_hir_ty(&mut self, _: &Ty<'_>, hasher: &mut StableHasher);
+    fn hash_hir_visibility_kind(&mut self, _: &VisibilityKind<'_>, hasher: &mut StableHasher);
+    fn hash_hir_item_like<F: FnOnce(&mut Self)>(&mut self, f: F);
+    fn local_def_path_hash(&self, def_id: LocalDefId) -> DefPathHash;
+}
+
+impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for HirId {
+    type KeyType = (DefPathHash, ItemLocalId);
+
+    #[inline]
+    fn to_stable_hash_key(&self, hcx: &HirCtx) -> (DefPathHash, ItemLocalId) {
+        let def_path_hash = hcx.local_def_path_hash(self.owner);
+        (def_path_hash, self.local_id)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for TraitItemId {
+    type KeyType = (DefPathHash, ItemLocalId);
+
+    #[inline]
+    fn to_stable_hash_key(&self, hcx: &HirCtx) -> (DefPathHash, ItemLocalId) {
+        self.hir_id.to_stable_hash_key(hcx)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ImplItemId {
+    type KeyType = (DefPathHash, ItemLocalId);
+
+    #[inline]
+    fn to_stable_hash_key(&self, hcx: &HirCtx) -> (DefPathHash, ItemLocalId) {
+        self.hir_id.to_stable_hash_key(hcx)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for HirId {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_hir_id(*self, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for BodyId {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_body_id(*self, hasher)
+    }
+}
+
+// The following implementations of HashStable for `ItemId`, `TraitItemId`, and
+// `ImplItemId` deserve special attention. Normally we do not hash `NodeId`s within
+// the HIR, since they just signify a HIR nodes own path. But `ItemId` et al
+// are used when another item in the HIR is *referenced* and we certainly
+// want to pick up on a reference changing its target, so we hash the NodeIds
+// in "DefPath Mode".
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ItemId {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_reference_to_item(self.id, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ImplItemId {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_reference_to_item(self.hir_id, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for TraitItemId {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_reference_to_item(self.hir_id, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Mod<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_hir_mod(self, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Expr<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_hir_expr(self, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Ty<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_hir_ty(self, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for VisibilityKind<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        hcx.hash_hir_visibility_kind(self, hasher)
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for TraitItem<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        let TraitItem { hir_id: _, ident, ref attrs, ref generics, ref kind, span } = *self;
+
+        hcx.hash_hir_item_like(|hcx| {
+            ident.name.hash_stable(hcx, hasher);
+            attrs.hash_stable(hcx, hasher);
+            generics.hash_stable(hcx, hasher);
+            kind.hash_stable(hcx, hasher);
+            span.hash_stable(hcx, hasher);
+        });
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ImplItem<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        let ImplItem {
+            hir_id: _,
+            ident,
+            ref vis,
+            defaultness,
+            ref attrs,
+            ref generics,
+            ref kind,
+            span,
+        } = *self;
+
+        hcx.hash_hir_item_like(|hcx| {
+            ident.name.hash_stable(hcx, hasher);
+            vis.hash_stable(hcx, hasher);
+            defaultness.hash_stable(hcx, hasher);
+            attrs.hash_stable(hcx, hasher);
+            generics.hash_stable(hcx, hasher);
+            kind.hash_stable(hcx, hasher);
+            span.hash_stable(hcx, hasher);
+        });
+    }
+}
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Item<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        let Item { ident, ref attrs, hir_id: _, ref kind, ref vis, span } = *self;
+
+        hcx.hash_hir_item_like(|hcx| {
+            ident.name.hash_stable(hcx, hasher);
+            attrs.hash_stable(hcx, hasher);
+            kind.hash_stable(hcx, hasher);
+            vis.hash_stable(hcx, hasher);
+            span.hash_stable(hcx, hasher);
+        });
+    }
+}