Auto merge of #88597 - cjgillot:lower-global, r=petrochenkov

Move global analyses from lowering to resolution

Split off #87234

r? `@petrochenkov`

Author: bors

compiler/rustc_ast/src/ast.rs

@@ -502,13 +502,6 @@ pub struct Crate {
     pub attrs: Vec<Attribute>,
     pub items: Vec<P<Item>>,
     pub span: Span,
-    /// The order of items in the HIR is unrelated to the order of
-    /// items in the AST. However, we generate proc macro harnesses
-    /// based on the AST order, and later refer to these harnesses
-    /// from the HIR. This field keeps track of the order in which
-    /// we generated proc macros harnesses, so that we can map
-    /// HIR proc macros items back to their harness items.
-    pub proc_macros: Vec<NodeId>,
 }
 
 /// Possible values inside of compile-time attribute lists.

compiler/rustc_ast/src/mut_visit.rs

@@ -1059,7 +1059,7 @@ pub fn noop_visit_fn_header<T: MutVisitor>(header: &mut FnHeader, vis: &mut T) {
 // FIXME: Avoid visiting the crate as a `Mod` item, flat map only the inner items if possible,
 // or make crate visiting first class if necessary.
 pub fn noop_visit_crate<T: MutVisitor>(krate: &mut Crate, vis: &mut T) {
-    visit_clobber(krate, |Crate { attrs, items, span, proc_macros }| {
+    visit_clobber(krate, |Crate { attrs, items, span }| {
         let item_vis =
             Visibility { kind: VisibilityKind::Public, span: span.shrink_to_lo(), tokens: None };
         let item = P(Item {
@@ -1075,13 +1075,11 @@ pub fn noop_visit_crate<T: MutVisitor>(krate: &mut Crate, vis: &mut T) {
 
         let len = items.len();
         if len == 0 {
-            Crate { attrs: vec![], items: vec![], span, proc_macros }
+            Crate { attrs: vec![], items: vec![], span }
         } else if len == 1 {
             let Item { attrs, span, kind, .. } = items.into_iter().next().unwrap().into_inner();
             match kind {
-                ItemKind::Mod(_, ModKind::Loaded(items, ..)) => {
-                    Crate { attrs, items, span, proc_macros }
-                }
+                ItemKind::Mod(_, ModKind::Loaded(items, ..)) => Crate { attrs, items, span },
                 _ => panic!("visitor converted a module to not a module"),
             }
         } else {

compiler/rustc_ast_lowering/src/item.rs

@@ -378,15 +378,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                             this.lower_trait_ref(trait_ref, ImplTraitContext::disallowed())
                         });
 
-                        if let Some(ref trait_ref) = trait_ref {
-                            if let Res::Def(DefKind::Trait, def_id) = trait_ref.path.res {
-                                this.trait_impls
-                                    .entry(def_id)
-                                    .or_default()
-                                    .push(lowered_trait_def_id);
-                            }
-                        }
-
                         let lowered_ty = this.lower_ty(ty, ImplTraitContext::disallowed());
 
                         (trait_ref, lowered_ty)

compiler/rustc_ast_lowering/src/lib.rs

@@ -39,7 +39,6 @@ use rustc_ast::node_id::NodeMap;
 use rustc_ast::token::{self, Token};
 use rustc_ast::tokenstream::{CanSynthesizeMissingTokens, TokenStream, TokenTree};
 use rustc_ast::visit::{self, AssocCtxt, Visitor};
-use rustc_ast::walk_list;
 use rustc_ast::{self as ast, *};
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::captures::Captures;
@@ -48,7 +47,7 @@ use rustc_data_structures::sync::Lrc;
 use rustc_errors::{struct_span_err, Applicability};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Namespace, PartialRes, PerNS, Res};
-use rustc_hir::def_id::{DefId, DefIdMap, DefPathHash, LocalDefId, CRATE_DEF_ID};
+use rustc_hir::def_id::{DefId, DefPathHash, LocalDefId, CRATE_DEF_ID};
 use rustc_hir::definitions::{DefKey, DefPathData, Definitions};
 use rustc_hir::intravisit;
 use rustc_hir::{ConstArg, GenericArg, InferKind, ParamName};
@@ -104,8 +103,6 @@ struct LoweringContext<'a, 'hir: 'a> {
     owners: IndexVec<LocalDefId, Option<hir::OwnerNode<'hir>>>,
     bodies: BTreeMap<hir::BodyId, hir::Body<'hir>>,
 
-    trait_impls: BTreeMap<DefId, Vec<LocalDefId>>,
-
     modules: BTreeMap<LocalDefId, hir::ModuleItems>,
 
     generator_kind: Option<hir::GeneratorKind>,
@@ -158,8 +155,6 @@ struct LoweringContext<'a, 'hir: 'a> {
 
     current_module: LocalDefId,
 
-    type_def_lifetime_params: DefIdMap<usize>,
-
     current_hir_id_owner: (LocalDefId, u32),
     item_local_id_counters: NodeMap<u32>,
     node_id_to_hir_id: IndexVec<NodeId, Option<hir::HirId>>,
@@ -171,7 +166,7 @@ struct LoweringContext<'a, 'hir: 'a> {
 pub trait ResolverAstLowering {
     fn def_key(&mut self, id: DefId) -> DefKey;
 
-    fn item_generics_num_lifetimes(&self, def: DefId, sess: &Session) -> usize;
+    fn item_generics_num_lifetimes(&self, def: DefId) -> usize;
 
     fn legacy_const_generic_args(&mut self, expr: &Expr) -> Option<Vec<usize>>;
 
@@ -326,7 +321,6 @@ pub fn lower_crate<'a, 'hir>(
         arena,
         owners: IndexVec::default(),
         bodies: BTreeMap::new(),
-        trait_impls: BTreeMap::new(),
         modules: BTreeMap::new(),
         attrs: BTreeMap::default(),
         catch_scopes: Vec::new(),
@@ -335,7 +329,6 @@ pub fn lower_crate<'a, 'hir>(
         is_in_trait_impl: false,
         is_in_dyn_type: false,
         anonymous_lifetime_mode: AnonymousLifetimeMode::PassThrough,
-        type_def_lifetime_params: Default::default(),
         current_module: CRATE_DEF_ID,
         current_hir_id_owner: (CRATE_DEF_ID, 0),
         item_local_id_counters: Default::default(),
@@ -451,26 +444,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             fn visit_item(&mut self, item: &'tcx Item) {
                 self.lctx.allocate_hir_id_counter(item.id);
 
-                match item.kind {
-                    ItemKind::Struct(_, ref generics)
-                    | ItemKind::Union(_, ref generics)
-                    | ItemKind::Enum(_, ref generics)
-                    | ItemKind::TyAlias(box TyAliasKind(_, ref generics, ..))
-                    | ItemKind::Trait(box TraitKind(_, _, ref generics, ..)) => {
-                        let def_id = self.lctx.resolver.local_def_id(item.id);
-                        let count = generics
-                            .params
-                            .iter()
-                            .filter(|param| {
-                                matches!(param.kind, ast::GenericParamKind::Lifetime { .. })
-                            })
-                            .count();
-                        self.lctx.type_def_lifetime_params.insert(def_id.to_def_id(), count);
-                    }
-                    ItemKind::Use(ref use_tree) => {
-                        self.allocate_use_tree_hir_id_counters(use_tree);
-                    }
-                    _ => {}
+                if let ItemKind::Use(ref use_tree) = item.kind {
+                    self.allocate_use_tree_hir_id_counters(use_tree);
                 }
 
                 visit::walk_item(self, item);
@@ -485,23 +460,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 self.lctx.allocate_hir_id_counter(item.id);
                 visit::walk_foreign_item(self, item);
             }
-
-            fn visit_ty(&mut self, t: &'tcx Ty) {
-                match t.kind {
-                    // Mirrors the case in visit::walk_ty
-                    TyKind::BareFn(ref f) => {
-                        walk_list!(self, visit_generic_param, &f.generic_params);
-                        // Mirrors visit::walk_fn_decl
-                        for parameter in &f.decl.inputs {
-                            // We don't lower the ids of argument patterns
-                            self.visit_pat(&parameter.pat);
-                            self.visit_ty(&parameter.ty)
-                        }
-                        self.visit_fn_ret_ty(&f.decl.output)
-                    }
-                    _ => visit::walk_ty(self, t),
-                }
-            }
         }
 
         self.lower_node_id(CRATE_NODE_ID);
@@ -515,10 +473,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.owners.ensure_contains_elem(CRATE_DEF_ID, || None);
         self.owners[CRATE_DEF_ID] = Some(hir::OwnerNode::Crate(module));
 
-        let body_ids = body_ids(&self.bodies);
-        let proc_macros =
-            c.proc_macros.iter().map(|id| self.node_id_to_hir_id[*id].unwrap()).collect();
-
         let mut trait_map: FxHashMap<_, FxHashMap<_, _>> = FxHashMap::default();
         for (k, v) in self.resolver.take_trait_map().into_iter() {
             if let Some(Some(hir_id)) = self.node_id_to_hir_id.get(k) {
@@ -551,10 +505,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         let krate = hir::Crate {
             owners: self.owners,
             bodies: self.bodies,
-            body_ids,
-            trait_impls: self.trait_impls,
             modules: self.modules,
-            proc_macros,
             trait_map,
             attrs: self.attrs,
         };
@@ -2749,14 +2700,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     }
 }
 
-fn body_ids(bodies: &BTreeMap<hir::BodyId, hir::Body<'_>>) -> Vec<hir::BodyId> {
-    // Sorting by span ensures that we get things in order within a
-    // file, and also puts the files in a sensible order.
-    let mut body_ids: Vec<_> = bodies.keys().cloned().collect();
-    body_ids.sort_by_key(|b| bodies[b].value.span);
-    body_ids
-}
-
 /// Helper struct for delayed construction of GenericArgs.
 struct GenericArgsCtor<'hir> {
     args: SmallVec<[hir::GenericArg<'hir>; 4]>,

compiler/rustc_ast_lowering/src/path.rs

@@ -90,15 +90,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         _ => ParenthesizedGenericArgs::Err,
                     };
 
-                    let num_lifetimes = type_def_id.map_or(0, |def_id| {
-                        if let Some(&n) = self.type_def_lifetime_params.get(&def_id) {
-                            return n;
-                        }
-                        assert!(!def_id.is_local());
-                        let n = self.resolver.item_generics_num_lifetimes(def_id, self.sess);
-                        self.type_def_lifetime_params.insert(def_id, n);
-                        n
-                    });
+                    let num_lifetimes = type_def_id
+                        .map_or(0, |def_id| self.resolver.item_generics_num_lifetimes(def_id));
                     self.lower_path_segment(
                         p.span,
                         segment,

compiler/rustc_builtin_macros/src/proc_macro_harness.rs

@@ -13,7 +13,6 @@ use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use smallvec::smallvec;
-use std::cell::RefCell;
 
 struct ProcMacroDerive {
     id: NodeId,
@@ -90,7 +89,7 @@ pub fn inject(
         return krate;
     }
 
-    let decls = mk_decls(&mut krate, &mut cx, &macros);
+    let decls = mk_decls(&mut cx, &macros);
     krate.items.push(decls);
 
     krate
@@ -289,15 +288,7 @@ impl<'a> Visitor<'a> for CollectProcMacros<'a> {
 //              // ...
 //          ];
 //      }
-fn mk_decls(
-    ast_krate: &mut ast::Crate,
-    cx: &mut ExtCtxt<'_>,
-    macros: &[ProcMacro],
-) -> P<ast::Item> {
-    // We're the ones filling in this Vec,
-    // so it should be empty to start with
-    assert!(ast_krate.proc_macros.is_empty());
-
+fn mk_decls(cx: &mut ExtCtxt<'_>, macros: &[ProcMacro]) -> P<ast::Item> {
     let expn_id = cx.resolver.expansion_for_ast_pass(
         DUMMY_SP,
         AstPass::ProcMacroHarness,
@@ -316,26 +307,25 @@ fn mk_decls(
     let attr = Ident::new(sym::attr, span);
     let bang = Ident::new(sym::bang, span);
 
-    let krate_ref = RefCell::new(ast_krate);
-
-    // We add NodeIds to 'krate.proc_macros' in the order
+    // We add NodeIds to 'resolver.proc_macros' in the order
     // that we generate expressions. The position of each NodeId
     // in the 'proc_macros' Vec corresponds to its position
     // in the static array that will be generated
     let decls = {
-        let local_path =
-            |sp: Span, name| cx.expr_path(cx.path(sp.with_ctxt(span.ctxt()), vec![name]));
-        let proc_macro_ty_method_path = |method| {
+        let local_path = |cx: &ExtCtxt<'_>, sp: Span, name| {
+            cx.expr_path(cx.path(sp.with_ctxt(span.ctxt()), vec![name]))
+        };
+        let proc_macro_ty_method_path = |cx: &ExtCtxt<'_>, method| {
             cx.expr_path(cx.path(span, vec![proc_macro, bridge, client, proc_macro_ty, method]))
         };
         macros
             .iter()
             .map(|m| match m {
                 ProcMacro::Derive(cd) => {
-                    krate_ref.borrow_mut().proc_macros.push(cd.id);
+                    cx.resolver.declare_proc_macro(cd.id);
                     cx.expr_call(
                         span,
-                        proc_macro_ty_method_path(custom_derive),
+                        proc_macro_ty_method_path(cx, custom_derive),
                         vec![
                             cx.expr_str(cd.span, cd.trait_name),
                             cx.expr_vec_slice(
@@ -345,23 +335,23 @@ fn mk_decls(
                                     .map(|&s| cx.expr_str(cd.span, s))
                                     .collect::<Vec<_>>(),
                             ),
-                            local_path(cd.span, cd.function_name),
+                            local_path(cx, cd.span, cd.function_name),
                         ],
                     )
                 }
                 ProcMacro::Def(ca) => {
-                    krate_ref.borrow_mut().proc_macros.push(ca.id);
+                    cx.resolver.declare_proc_macro(ca.id);
                     let ident = match ca.def_type {
                         ProcMacroDefType::Attr => attr,
                         ProcMacroDefType::Bang => bang,
                     };
 
                     cx.expr_call(
                         span,
-                        proc_macro_ty_method_path(ident),
+                        proc_macro_ty_method_path(cx, ident),
                         vec![
                             cx.expr_str(ca.span, ca.function_name.name),
-                            local_path(ca.span, ca.function_name),
+                            local_path(cx, ca.span, ca.function_name),
                         ],
                     )
                 }

compiler/rustc_expand/src/base.rs

@@ -894,6 +894,14 @@ pub trait ResolverExpand {
     /// Decodes the proc-macro quoted span in the specified crate, with the specified id.
     /// No caching is performed.
     fn get_proc_macro_quoted_span(&self, krate: CrateNum, id: usize) -> Span;
+
+    /// The order of items in the HIR is unrelated to the order of
+    /// items in the AST. However, we generate proc macro harnesses
+    /// based on the AST order, and later refer to these harnesses
+    /// from the HIR. This field keeps track of the order in which
+    /// we generated proc macros harnesses, so that we can map
+    /// HIR proc macros items back to their harness items.
+    fn declare_proc_macro(&mut self, id: NodeId);
 }
 
 #[derive(Clone, Default)]

compiler/rustc_hir/src/hir.rs

@@ -672,20 +672,10 @@ pub struct ModuleItems {
 pub struct Crate<'hir> {
     pub owners: IndexVec<LocalDefId, Option<OwnerNode<'hir>>>,
     pub bodies: BTreeMap<BodyId, Body<'hir>>,
-    pub trait_impls: BTreeMap<DefId, Vec<LocalDefId>>,
-
-    /// A list of the body ids written out in the order in which they
-    /// appear in the crate. If you're going to process all the bodies
-    /// in the crate, you should iterate over this list rather than the keys
-    /// of bodies.
-    pub body_ids: Vec<BodyId>,
 
     /// A list of modules written out in the order in which they
     /// appear in the crate. This includes the main crate module.
     pub modules: BTreeMap<LocalDefId, ModuleItems>,
-    /// A list of proc macro HirIds, written out in the order in which
-    /// they are declared in the static array generated by proc_macro_harness.
-    pub proc_macros: Vec<HirId>,
 
     /// Map indicating what traits are in scope for places where this
     /// is relevant; generated by resolve.

compiler/rustc_interface/src/passes.rs

@@ -324,7 +324,7 @@ pub fn configure_and_expand(
         };
 
         let extern_mod_loaded = |ident: Ident, attrs, items, span| {
-            let krate = ast::Crate { attrs, items, span, proc_macros: vec![] };
+            let krate = ast::Crate { attrs, items, span };
             pre_expansion_lint(sess, lint_store, &krate, &ident.name.as_str());
             (krate.attrs, krate.items)
         };