Encode def_ident_span using the query.

Author: cjgillot

compiler/rustc_metadata/src/rmeta/decoder.rs

@@ -774,17 +774,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
 
     fn opt_item_ident(self, item_index: DefIndex, sess: &Session) -> Option<Ident> {
         let name = self.opt_item_name(item_index)?;
-        let span = match self.root.tables.def_ident_span.get(self, item_index) {
-            Some(lazy_span) => lazy_span.decode((self, sess)),
-            None => {
-                // FIXME: this weird case of a name with no span is specific to `extern crate`
-                // items, which are supposed to be treated like `use` items and only be encoded
-                // to metadata as `Export`s, return `None` because that's what all the callers
-                // expect in this case.
-                assert_eq!(self.def_kind(item_index), DefKind::ExternCrate);
-                return None;
-            }
-        };
+        let span = self.root.tables.def_ident_span.get(self, item_index)?.decode((self, sess));
         Some(Ident::new(name, span))
     }
 

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -31,7 +31,7 @@ use rustc_serialize::{opaque, Encodable, Encoder};
 use rustc_session::config::CrateType;
 use rustc_session::cstore::{ForeignModule, LinkagePreference, NativeLib};
 use rustc_span::hygiene::{ExpnIndex, HygieneEncodeContext, MacroKind};
-use rustc_span::symbol::{sym, Ident, Symbol};
+use rustc_span::symbol::{sym, Symbol};
 use rustc_span::{
     self, DebuggerVisualizerFile, ExternalSource, FileName, SourceFile, Span, SyntaxContext,
 };
@@ -1011,6 +1011,9 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             record!(self.tables.def_span[def_id] <- tcx.def_span(def_id));
             self.encode_attrs(local_id);
             record!(self.tables.expn_that_defined[def_id] <- self.tcx.expn_that_defined(def_id));
+            if let Some(ident_span) = tcx.def_ident_span(def_id) {
+                record!(self.tables.def_ident_span[def_id] <- ident_span);
+            }
             if def_kind.has_codegen_attrs() {
                 record!(self.tables.codegen_fn_attrs[def_id] <- self.tcx.codegen_fn_attrs(def_id));
             }
@@ -1075,7 +1078,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             assert!(f.did.is_local());
             f.did.index
         }));
-        self.encode_ident_span(def_id, variant.ident(tcx));
         self.encode_item_type(def_id);
         if variant.ctor_kind == CtorKind::Fn {
             // FIXME(eddyb) encode signature only in `encode_enum_variant_ctor`.
@@ -1167,7 +1169,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         debug!("EncodeContext::encode_field({:?})", def_id);
 
         record!(self.tables.kind[def_id] <- EntryKind::Field);
-        self.encode_ident_span(def_id, field.ident(self.tcx));
         self.encode_item_type(def_id);
     }
 
@@ -1246,7 +1247,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 record!(self.tables.kind[def_id] <- EntryKind::AssocType(container));
             }
         }
-        self.encode_ident_span(def_id, ast_item.ident);
         match trait_item.kind {
             ty::AssocKind::Const | ty::AssocKind::Fn => {
                 self.encode_item_type(def_id);
@@ -1310,7 +1310,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 record!(self.tables.kind[def_id] <- EntryKind::AssocType(container));
             }
         }
-        self.encode_ident_span(def_id, impl_item.ident(self.tcx));
         self.encode_item_type(def_id);
         if let Some(trait_item_def_id) = impl_item.trait_item_def_id {
             self.tables.trait_item_def_id.set(def_id.index, trait_item_def_id.into());
@@ -1412,8 +1411,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
 
         debug!("EncodeContext::encode_info_for_item({:?})", def_id);
 
-        self.encode_ident_span(def_id, item.ident);
-
         let entry_kind = match item.kind {
             hir::ItemKind::Static(..) => EntryKind::Static,
             hir::ItemKind::Const(_, body_id) => {
@@ -1959,7 +1956,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 record!(self.tables.kind[def_id] <- EntryKind::ForeignType);
             }
         }
-        self.encode_ident_span(def_id, nitem.ident);
         self.encode_item_type(def_id);
         if let hir::ForeignItemKind::Fn(..) = nitem.kind {
             record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
@@ -2041,10 +2037,6 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
         }
     }
 
-    fn encode_ident_span(&mut self, def_id: DefId, ident: Ident) {
-        record!(self.tables.def_ident_span[def_id] <- ident.span);
-    }
-
     /// In some cases, along with the item itself, we also
     /// encode some sub-items. Usually we want some info from the item
     /// so it's easier to do that here then to wait until we would encounter