Auto merge of #79353 - cjgillot:procmacro, r=petrochenkov

Setup proc-macro metadata at encoding instead of decoding

This should improve the common non-proc-macro case for metadata decoding.

compiler/rustc_metadata/src/rmeta/decoder.rs

@@ -644,6 +644,7 @@ fn def_kind(&self) -> DefKind {
             EntryKind::TraitAlias => DefKind::TraitAlias,
             EntryKind::Enum(..) => DefKind::Enum,
             EntryKind::MacroDef(_) => DefKind::Macro(MacroKind::Bang),
+            EntryKind::ProcMacro(kind) => DefKind::Macro(kind),
             EntryKind::ForeignType => DefKind::ForeignTy,
             EntryKind::Impl(_) => DefKind::Impl,
             EntryKind::Closure => DefKind::Closure,
@@ -685,20 +686,11 @@ impl CrateRoot<'_> {
 }
 
 impl<'a, 'tcx> CrateMetadataRef<'a> {
-    fn is_proc_macro(&self, id: DefIndex) -> bool {
-        self.root
-            .proc_macro_data
-            .as_ref()
-            .and_then(|data| data.macros.decode(self).find(|x| *x == id))
-            .is_some()
-    }
-
     fn maybe_kind(&self, item_id: DefIndex) -> Option<EntryKind> {
         self.root.tables.kind.get(self, item_id).map(|k| k.decode(self))
     }
 
     fn kind(&self, item_id: DefIndex) -> EntryKind {
-        assert!(!self.is_proc_macro(item_id));
         self.maybe_kind(item_id).unwrap_or_else(|| {
             bug!(
                 "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}",
@@ -725,35 +717,24 @@ fn raw_proc_macro(&self, id: DefIndex) -> &ProcMacro {
     }
 
     fn item_ident(&self, item_index: DefIndex, sess: &Session) -> Ident {
-        if !self.is_proc_macro(item_index) {
-            let name = self
-                .def_key(item_index)
-                .disambiguated_data
-                .data
-                .get_opt_name()
-                .expect("no name in item_ident");
-            let span = self
-                .root
-                .tables
-                .ident_span
-                .get(self, item_index)
-                .map(|data| data.decode((self, sess)))
-                .unwrap_or_else(|| panic!("Missing ident span for {:?} ({:?})", name, item_index));
-            Ident::new(name, span)
-        } else {
-            Ident::new(
-                Symbol::intern(self.raw_proc_macro(item_index).name()),
-                self.get_span(item_index, sess),
-            )
-        }
+        let name = self
+            .def_key(item_index)
+            .disambiguated_data
+            .data
+            .get_opt_name()
+            .expect("no name in item_ident");
+        let span = self
+            .root
+            .tables
+            .ident_span
+            .get(self, item_index)
+            .map(|data| data.decode((self, sess)))
+            .unwrap_or_else(|| panic!("Missing ident span for {:?} ({:?})", name, item_index));
+        Ident::new(name, span)
     }
 
     fn def_kind(&self, index: DefIndex) -> DefKind {
-        if !self.is_proc_macro(index) {
-            self.kind(index).def_kind()
-        } else {
-            DefKind::Macro(macro_kind(self.raw_proc_macro(index)))
-        }
+        self.kind(index).def_kind()
     }
 
     fn get_span(&self, index: DefIndex, sess: &Session) -> Span {
@@ -956,10 +937,7 @@ fn get_type(&self, id: DefIndex, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
     }
 
     fn get_stability(&self, id: DefIndex) -> Option<attr::Stability> {
-        match self.is_proc_macro(id) {
-            true => self.root.proc_macro_data.as_ref().unwrap().stability,
-            false => self.root.tables.stability.get(self, id).map(|stab| stab.decode(self)),
-        }
+        self.root.tables.stability.get(self, id).map(|stab| stab.decode(self))
     }
 
     fn get_const_stability(&self, id: DefIndex) -> Option<attr::ConstStability> {
@@ -967,19 +945,11 @@ fn get_const_stability(&self, id: DefIndex) -> Option<attr::ConstStability> {
     }
 
     fn get_deprecation(&self, id: DefIndex) -> Option<attr::Deprecation> {
-        self.root
-            .tables
-            .deprecation
-            .get(self, id)
-            .filter(|_| !self.is_proc_macro(id))
-            .map(|depr| depr.decode(self))
+        self.root.tables.deprecation.get(self, id).map(|depr| depr.decode(self))
     }
 
     fn get_visibility(&self, id: DefIndex) -> ty::Visibility {
-        match self.is_proc_macro(id) {
-            true => ty::Visibility::Public,
-            false => self.root.tables.visibility.get(self, id).unwrap().decode(self),
-        }
+        self.root.tables.visibility.get(self, id).unwrap().decode(self)
     }
 
     fn get_impl_data(&self, id: DefIndex) -> ImplData {
@@ -1191,7 +1161,7 @@ fn each_child_of_item<F>(&self, id: DefIndex, mut callback: F, sess: &Session)
     }
 
     fn is_item_mir_available(&self, id: DefIndex) -> bool {
-        !self.is_proc_macro(id) && self.root.tables.mir.get(self, id).is_some()
+        self.root.tables.mir.get(self, id).is_some()
     }
 
     fn module_expansion(&self, id: DefIndex, sess: &Session) -> ExpnId {
@@ -1207,7 +1177,6 @@ fn get_optimized_mir(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> Body<'tcx> {
             .tables
             .mir
             .get(self, id)
-            .filter(|_| !self.is_proc_macro(id))
             .unwrap_or_else(|| {
                 bug!("get_optimized_mir: missing MIR for `{:?}`", self.local_def_id(id))
             })
@@ -1223,7 +1192,6 @@ fn get_mir_abstract_const(
             .tables
             .mir_abstract_consts
             .get(self, id)
-            .filter(|_| !self.is_proc_macro(id))
             .map_or(Ok(None), |v| Ok(Some(v.decode((self, tcx)))))
     }
 
@@ -1232,7 +1200,6 @@ fn get_unused_generic_params(&self, id: DefIndex) -> FiniteBitSet<u32> {
             .tables
             .unused_generic_params
             .get(self, id)
-            .filter(|_| !self.is_proc_macro(id))
             .map(|params| params.decode(self))
             .unwrap_or_default()
     }
@@ -1242,7 +1209,6 @@ fn get_promoted_mir(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> IndexVec<Promoted
             .tables
             .promoted_mir
             .get(self, id)
-            .filter(|_| !self.is_proc_macro(id))
             .unwrap_or_else(|| {
                 bug!("get_promoted_mir: missing MIR for `{:?}`", self.local_def_id(id))
             })
@@ -1546,14 +1512,11 @@ fn fn_sig(&self, id: DefIndex, tcx: TyCtxt<'tcx>) -> ty::PolyFnSig<'tcx> {
 
     #[inline]
     fn def_key(&self, index: DefIndex) -> DefKey {
-        *self.def_key_cache.lock().entry(index).or_insert_with(|| {
-            let mut key = self.root.tables.def_keys.get(self, index).unwrap().decode(self);
-            if self.is_proc_macro(index) {
-                let name = self.raw_proc_macro(index).name();
-                key.disambiguated_data.data = DefPathData::MacroNs(Symbol::intern(name));
-            }
-            key
-        })
+        *self
+            .def_key_cache
+            .lock()
+            .entry(index)
+            .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self))
     }
 
     // Returns the path leading to the thing with this `id`.

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -9,6 +9,7 @@
 use rustc_hir as hir;
 use rustc_hir::def::CtorKind;
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::definitions::DefPathData;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_hir::itemlikevisit::{ItemLikeVisitor, ParItemLikeVisitor};
 use rustc_hir::lang_items;
@@ -27,7 +28,7 @@
 use rustc_middle::ty::{self, SymbolName, Ty, TyCtxt};
 use rustc_serialize::{opaque, Encodable, Encoder};
 use rustc_session::config::CrateType;
-use rustc_span::hygiene::{ExpnDataEncodeMode, HygieneEncodeContext};
+use rustc_span::hygiene::{ExpnDataEncodeMode, HygieneEncodeContext, MacroKind};
 use rustc_span::symbol::{sym, Ident, Symbol};
 use rustc_span::{self, ExternalSource, FileName, SourceFile, Span, SyntaxContext};
 use rustc_target::abi::VariantIdx;
@@ -1539,12 +1540,41 @@ fn encode_proc_macros(&mut self) -> Option<ProcMacroData> {
             // so we manually encode just the information that we need
             for proc_macro in &hir.krate().proc_macros {
                 let id = proc_macro.owner.local_def_index;
-                let span = self.lazy(hir.span(*proc_macro));
+                let mut name = hir.name(*proc_macro);
+                let span = hir.span(*proc_macro);
                 // Proc-macros may have attributes like `#[allow_internal_unstable]`,
                 // so downstream crates need access to them.
-                let attrs = self.lazy(hir.attrs(*proc_macro));
-                self.tables.span.set(id, span);
-                self.tables.attributes.set(id, attrs);
+                let attrs = hir.attrs(*proc_macro);
+                let macro_kind = if tcx.sess.contains_name(attrs, sym::proc_macro) {
+                    MacroKind::Bang
+                } else if tcx.sess.contains_name(attrs, sym::proc_macro_attribute) {
+                    MacroKind::Attr
+                } else if let Some(attr) = tcx.sess.find_by_name(attrs, sym::proc_macro_derive) {
+                    // This unwrap chain should have been checked by the proc-macro harness.
+                    name = attr.meta_item_list().unwrap()[0]
+                        .meta_item()
+                        .unwrap()
+                        .ident()
+                        .unwrap()
+                        .name;
+                    MacroKind::Derive
+                } else {
+                    bug!("Unknown proc-macro type for item {:?}", id);
+                };
+
+                let mut def_key = self.tcx.hir().def_key(proc_macro.owner);
+                def_key.disambiguated_data.data = DefPathData::MacroNs(name);
+
+                let def_id = DefId::local(id);
+                record!(self.tables.kind[def_id] <- EntryKind::ProcMacro(macro_kind));
+                record!(self.tables.attributes[def_id] <- attrs);
+                record!(self.tables.def_keys[def_id] <- def_key);
+                record!(self.tables.ident_span[def_id] <- span);
+                record!(self.tables.span[def_id] <- span);
+                record!(self.tables.visibility[def_id] <- ty::Visibility::Public);
+                if let Some(stability) = stability {
+                    record!(self.tables.stability[def_id] <- stability);
+                }
             }
 
             Some(ProcMacroData { proc_macro_decls_static, stability, macros })

compiler/rustc_metadata/src/rmeta/mod.rs

@@ -20,6 +20,7 @@
 use rustc_session::config::SymbolManglingVersion;
 use rustc_session::CrateDisambiguator;
 use rustc_span::edition::Edition;
+use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::{self, ExpnData, ExpnId, Span};
 use rustc_target::spec::{PanicStrategy, TargetTriple};
@@ -336,6 +337,7 @@ enum EntryKind {
     ForeignFn(Lazy<FnData>),
     Mod(Lazy<ModData>),
     MacroDef(Lazy<MacroDef>),
+    ProcMacro(MacroKind),
     Closure,
     Generator(hir::GeneratorKind),
     Trait(Lazy<TraitData>),