Treat macros as HIR items

Author: inquisitivecrystal

Cargo.lock

@@ -4146,6 +4146,7 @@ dependencies = [
 name = "rustc_privacy"
 version = "0.0.0"
 dependencies = [
+ "rustc_ast",
  "rustc_attr",
  "rustc_data_structures",
  "rustc_errors",

compiler/rustc_ast_lowering/src/item.rs

@@ -170,7 +170,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 self.lower_item_id_use_tree(use_tree, i.id, &mut vec);
                 vec
             }
-            ItemKind::MacroDef(..) => SmallVec::new(),
             ItemKind::Fn(..) | ItemKind::Impl(box ImplKind { of_trait: None, .. }) => {
                 smallvec![i.id]
             }
@@ -212,28 +211,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
     pub fn lower_item(&mut self, i: &Item) -> Option<hir::Item<'hir>> {
         let mut ident = i.ident;
         let mut vis = self.lower_visibility(&i.vis, None);
-
-        if let ItemKind::MacroDef(MacroDef { ref body, macro_rules }) = i.kind {
-            if !macro_rules || self.sess.contains_name(&i.attrs, sym::macro_export) {
-                let hir_id = self.lower_node_id(i.id);
-                self.lower_attrs(hir_id, &i.attrs);
-                let body = P(self.lower_mac_args(body));
-                self.insert_macro_def(hir::MacroDef {
-                    ident,
-                    vis,
-                    def_id: hir_id.expect_owner(),
-                    span: i.span,
-                    ast: MacroDef { body, macro_rules },
-                });
-            } else {
-                for a in i.attrs.iter() {
-                    let a = self.lower_attr(a);
-                    self.non_exported_macro_attrs.push(a);
-                }
-            }
-            return None;
-        }
-
         let hir_id = self.lower_node_id(i.id);
         let attrs = self.lower_attrs(hir_id, &i.attrs);
         let kind = self.lower_item_kind(i.span, i.id, hir_id, &mut ident, attrs, &mut vis, &i.kind);
@@ -465,7 +442,12 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 self.lower_generics(generics, ImplTraitContext::disallowed()),
                 self.lower_param_bounds(bounds, ImplTraitContext::disallowed()),
             ),
-            ItemKind::MacroDef(..) | ItemKind::MacCall(..) => {
+            ItemKind::MacroDef(MacroDef { ref body, macro_rules }) => {
+                let body = P(self.lower_mac_args(body));
+
+                hir::ItemKind::Macro(ast::MacroDef { body, macro_rules })
+            }
+            ItemKind::MacCall(..) => {
                 panic!("`TyMac` should have been expanded by now")
             }
         }

compiler/rustc_ast_lowering/src/lib.rs

@@ -103,7 +103,6 @@ struct LoweringContext<'a, 'hir: 'a> {
     /// The items being lowered are collected here.
     owners: IndexVec<LocalDefId, Option<hir::OwnerNode<'hir>>>,
     bodies: BTreeMap<hir::BodyId, hir::Body<'hir>>,
-    non_exported_macro_attrs: Vec<ast::Attribute>,
 
     trait_impls: BTreeMap<DefId, Vec<LocalDefId>>,
 
@@ -330,7 +329,6 @@ pub fn lower_crate<'a, 'hir>(
         trait_impls: BTreeMap::new(),
         modules: BTreeMap::new(),
         attrs: BTreeMap::default(),
-        non_exported_macro_attrs: Vec::new(),
         catch_scopes: Vec::new(),
         loop_scopes: Vec::new(),
         is_in_loop_condition: false,
@@ -551,7 +549,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         }
 
         let krate = hir::Crate {
-            non_exported_macro_attrs: self.arena.alloc_from_iter(self.non_exported_macro_attrs),
             owners: self.owners,
             bodies: self.bodies,
             body_ids,
@@ -600,13 +597,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         id
     }
 
-    fn insert_macro_def(&mut self, item: hir::MacroDef<'hir>) {
-        let def_id = item.def_id;
-        let item = self.arena.alloc(item);
-        self.owners.ensure_contains_elem(def_id, || None);
-        self.owners[def_id] = Some(hir::OwnerNode::MacroDef(item));
-    }
-
     fn allocate_hir_id_counter(&mut self, owner: NodeId) -> hir::HirId {
         // Set up the counter if needed.
         self.item_local_id_counters.entry(owner).or_insert(0);

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -578,6 +578,33 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
         }
     }
 
+    fn print_mac_def(
+        &mut self,
+        macro_def: &ast::MacroDef,
+        ident: &Ident,
+        sp: &Span,
+        print_visibility: impl FnOnce(&mut Self),
+    ) {
+        let (kw, has_bang) = if macro_def.macro_rules {
+            ("macro_rules", true)
+        } else {
+            print_visibility(self);
+            ("macro", false)
+        };
+        self.print_mac_common(
+            Some(MacHeader::Keyword(kw)),
+            has_bang,
+            Some(*ident),
+            macro_def.body.delim(),
+            &macro_def.body.inner_tokens(),
+            true,
+            *sp,
+        );
+        if macro_def.body.need_semicolon() {
+            self.word(";");
+        }
+    }
+
     fn print_path(&mut self, path: &ast::Path, colons_before_params: bool, depth: usize) {
         self.maybe_print_comment(path.span.lo());
 
@@ -1305,24 +1332,9 @@ impl<'a> State<'a> {
                 }
             }
             ast::ItemKind::MacroDef(ref macro_def) => {
-                let (kw, has_bang) = if macro_def.macro_rules {
-                    ("macro_rules", true)
-                } else {
-                    self.print_visibility(&item.vis);
-                    ("macro", false)
-                };
-                self.print_mac_common(
-                    Some(MacHeader::Keyword(kw)),
-                    has_bang,
-                    Some(item.ident),
-                    macro_def.body.delim(),
-                    &macro_def.body.inner_tokens(),
-                    true,
-                    item.span,
-                );
-                if macro_def.body.need_semicolon() {
-                    self.word(";");
-                }
+                self.print_mac_def(macro_def, &item.ident, &item.span, |state| {
+                    state.print_visibility(&item.vis)
+                });
             }
         }
         self.ann.post(self, AnnNode::Item(item))

compiler/rustc_hir/src/arena.rs

@@ -35,7 +35,6 @@ macro_rules! arena_types {
             [few] inline_asm: rustc_hir::InlineAsm<$tcx>,
             [few] llvm_inline_asm: rustc_hir::LlvmInlineAsm<$tcx>,
             [] local: rustc_hir::Local<$tcx>,
-            [few] macro_def: rustc_hir::MacroDef<$tcx>,
             [few] mod_: rustc_hir::Mod<$tcx>,
             [] param: rustc_hir::Param<$tcx>,
             [] pat: rustc_hir::Pat<$tcx>,

compiler/rustc_hir/src/hir.rs

@@ -670,9 +670,6 @@ pub struct ModuleItems {
 /// [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/hir.html
 #[derive(Debug)]
 pub struct Crate<'hir> {
-    // Attributes from non-exported macros, kept only for collecting the library feature list.
-    pub non_exported_macro_attrs: &'hir [Attribute],
-
     pub owners: IndexVec<LocalDefId, Option<OwnerNode<'hir>>>,
     pub bodies: BTreeMap<BodyId, Body<'hir>>,
     pub trait_impls: BTreeMap<DefId, Vec<LocalDefId>>,
@@ -768,32 +765,6 @@ impl Crate<'_> {
             _ => None,
         })
     }
-
-    pub fn exported_macros<'hir>(&'hir self) -> impl Iterator<Item = &'hir MacroDef<'hir>> + 'hir {
-        self.owners.iter().filter_map(|owner| match owner {
-            Some(OwnerNode::MacroDef(macro_def)) => Some(*macro_def),
-            _ => None,
-        })
-    }
-}
-
-/// A macro definition, in this crate or imported from another.
-///
-/// Not parsed directly, but created on macro import or `macro_rules!` expansion.
-#[derive(Debug)]
-pub struct MacroDef<'hir> {
-    pub ident: Ident,
-    pub vis: Visibility<'hir>,
-    pub def_id: LocalDefId,
-    pub span: Span,
-    pub ast: ast::MacroDef,
-}
-
-impl MacroDef<'_> {
-    #[inline]
-    pub fn hir_id(&self) -> HirId {
-        HirId::make_owner(self.def_id)
-    }
 }
 
 /// A block of statements `{ .. }`, which may have a label (in this case the
@@ -2602,7 +2573,7 @@ pub struct PolyTraitRef<'hir> {
 
 pub type Visibility<'hir> = Spanned<VisibilityKind<'hir>>;
 
-#[derive(Debug)]
+#[derive(Copy, Clone, Debug)]
 pub enum VisibilityKind<'hir> {
     Public,
     Crate(CrateSugar),
@@ -2791,6 +2762,8 @@ pub enum ItemKind<'hir> {
     Const(&'hir Ty<'hir>, BodyId),
     /// A function declaration.
     Fn(FnSig<'hir>, Generics<'hir>, BodyId),
+    /// A MBE macro definition (`macro_rules!` or `macro`).
+    Macro(ast::MacroDef),
     /// A module.
     Mod(Mod<'hir>),
     /// An external module, e.g. `extern { .. }`.
@@ -2856,6 +2829,7 @@ impl ItemKind<'_> {
             ItemKind::Static(..) => "static item",
             ItemKind::Const(..) => "constant item",
             ItemKind::Fn(..) => "function",
+            ItemKind::Macro(..) => "macro",
             ItemKind::Mod(..) => "module",
             ItemKind::ForeignMod { .. } => "extern block",
             ItemKind::GlobalAsm(..) => "global asm item",

compiler/rustc_hir/src/intravisit.rs

@@ -466,9 +466,6 @@ pub trait Visitor<'v>: Sized {
         walk_assoc_type_binding(self, type_binding)
     }
     fn visit_attribute(&mut self, _id: HirId, _attr: &'v Attribute) {}
-    fn visit_macro_def(&mut self, macro_def: &'v MacroDef<'v>) {
-        walk_macro_def(self, macro_def)
-    }
     fn visit_vis(&mut self, vis: &'v Visibility<'v>) {
         walk_vis(self, vis)
     }
@@ -484,19 +481,13 @@ pub trait Visitor<'v>: Sized {
 pub fn walk_crate<'v, V: Visitor<'v>>(visitor: &mut V, krate: &'v Crate<'v>) {
     let top_mod = krate.module();
     visitor.visit_mod(top_mod, top_mod.inner, CRATE_HIR_ID);
-    walk_list!(visitor, visit_macro_def, krate.exported_macros());
     for (&id, attrs) in krate.attrs.iter() {
         for a in *attrs {
             visitor.visit_attribute(id, a)
         }
     }
 }
 
-pub fn walk_macro_def<'v, V: Visitor<'v>>(visitor: &mut V, macro_def: &'v MacroDef<'v>) {
-    visitor.visit_id(macro_def.hir_id());
-    visitor.visit_ident(macro_def.ident);
-}
-
 pub fn walk_mod<'v, V: Visitor<'v>>(visitor: &mut V, module: &'v Mod<'v>, mod_hir_id: HirId) {
     visitor.visit_id(mod_hir_id);
     for &item_id in module.item_ids {
@@ -586,6 +577,9 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) {
             item.span,
             item.hir_id(),
         ),
+        ItemKind::Macro(_) => {
+            visitor.visit_id(item.hir_id());
+        }
         ItemKind::Mod(ref module) => {
             // `visit_mod()` takes care of visiting the `Item`'s `HirId`.
             visitor.visit_mod(module, item.span, item.hir_id())

compiler/rustc_hir/src/stable_hash_impls.rs

@@ -1,8 +1,8 @@
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
 
 use crate::hir::{
-    BodyId, Expr, ForeignItem, ForeignItemId, ImplItem, ImplItemId, Item, ItemId, MacroDef, Mod,
-    TraitItem, TraitItemId, Ty, VisibilityKind,
+    BodyId, Expr, ForeignItem, ForeignItemId, ImplItem, ImplItemId, Item, ItemId, Mod, TraitItem,
+    TraitItemId, Ty, VisibilityKind,
 };
 use crate::hir_id::{HirId, ItemLocalId};
 use rustc_span::def_id::DefPathHash;
@@ -190,16 +190,3 @@ impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Item<'_> {
         });
     }
 }
-
-impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for MacroDef<'_> {
-    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
-        let MacroDef { ident, def_id: _, ref ast, ref vis, span } = *self;
-
-        hcx.hash_hir_item_like(|hcx| {
-            ident.name.hash_stable(hcx, hasher);
-            ast.hash_stable(hcx, hasher);
-            vis.hash_stable(hcx, hasher);
-            span.hash_stable(hcx, hasher);
-        });
-    }
-}

compiler/rustc_hir/src/target.rs

@@ -111,6 +111,7 @@ impl Target {
             ItemKind::Static(..) => Target::Static,
             ItemKind::Const(..) => Target::Const,
             ItemKind::Fn(..) => Target::Fn,
+            ItemKind::Macro(..) => Target::MacroDef,
             ItemKind::Mod(..) => Target::Mod,
             ItemKind::ForeignMod { .. } => Target::ForeignMod,
             ItemKind::GlobalAsm(..) => Target::GlobalAsm,

compiler/rustc_hir_pretty/src/lib.rs

@@ -642,6 +642,11 @@ impl<'a> State<'a> {
                 self.end(); // need to close a box
                 self.ann.nested(self, Nested::Body(body));
             }
+            hir::ItemKind::Macro(ref macro_def) => {
+                self.print_mac_def(macro_def, &item.ident, &item.span, |state| {
+                    state.print_visibility(&item.vis)
+                });
+            }
             hir::ItemKind::Mod(ref _mod) => {
                 self.head(visibility_qualified(&item.vis, "mod"));
                 self.print_ident(item.ident);

compiler/rustc_lint/src/builtin.rs

@@ -585,24 +585,6 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
 
     fn check_crate(&mut self, cx: &LateContext<'_>, krate: &hir::Crate<'_>) {
         self.check_missing_docs_attrs(cx, CRATE_DEF_ID, krate.module().inner, "the", "crate");
-
-        for macro_def in krate.exported_macros() {
-            // Non exported macros should be skipped, since `missing_docs` only
-            // applies to externally visible items.
-            if !cx.access_levels.is_exported(macro_def.def_id) {
-                continue;
-            }
-
-            let attrs = cx.tcx.hir().attrs(macro_def.hir_id());
-            let has_doc = attrs.iter().any(has_doc);
-            if !has_doc {
-                cx.struct_span_lint(
-                    MISSING_DOCS,
-                    cx.tcx.sess.source_map().guess_head_span(macro_def.span),
-                    |lint| lint.build("missing documentation for macro").emit(),
-                );
-            }
-        }
     }
 
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {
@@ -636,6 +618,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
 
             hir::ItemKind::TyAlias(..)
             | hir::ItemKind::Fn(..)
+            | hir::ItemKind::Macro(..)
             | hir::ItemKind::Mod(..)
             | hir::ItemKind::Enum(..)
             | hir::ItemKind::Struct(..)

compiler/rustc_lint/src/late.rs

@@ -453,10 +453,6 @@ fn late_lint_pass_crate<'tcx, T: LateLintPass<'tcx>>(tcx: TyCtxt<'tcx>, pass: T)
         lint_callback!(cx, check_crate, krate);
 
         hir_visit::walk_crate(cx, krate);
-        for attr in krate.non_exported_macro_attrs {
-            // This HIR ID is a lie, since the macro ID isn't available.
-            cx.visit_attribute(hir::CRATE_HIR_ID, attr);
-        }
 
         lint_callback!(cx, check_crate_post, krate);
     })

compiler/rustc_lint/src/levels.rs

@@ -37,9 +37,6 @@ fn lint_levels(tcx: TyCtxt<'_>, (): ()) -> LintLevelMap {
 
     let push = builder.levels.push(tcx.hir().attrs(hir::CRATE_HIR_ID), &store, true);
     builder.levels.register_id(hir::CRATE_HIR_ID);
-    for macro_def in krate.exported_macros() {
-        builder.levels.register_id(macro_def.hir_id());
-    }
     intravisit::walk_crate(&mut builder, krate);
     builder.levels.pop(push);
 

compiler/rustc_metadata/src/rmeta/decoder.rs

@@ -1100,7 +1100,13 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
                     let vis = self.get_visibility(child_index);
                     let def_id = self.local_def_id(child_index);
                     let res = Res::Def(kind, def_id);
-                    callback(Export { res, ident, vis, span });
+
+                    // FIXME: Macros are currently encoded twice, once as items and once as
+                    // reexports. We ignore the items here and only use the reexports.
+                    if !matches!(kind, DefKind::Macro(..)) {
+                        callback(Export { res, ident, vis, span });
+                    }
+
                     // For non-re-export structs and variants add their constructors to children.
                     // Re-export lists automatically contain constructors when necessary.
                     match kind {