Auto merge of #88880 - cjgillot:no-krate, r=oli-obk

Rework HIR API to make invocations of the hir_crate query harder.

`hir_crate` forces the recomputation of queries that depend on it.

This PR aims at avoiding useless invocations of `hir_crate` by making dependent code go through `tcx.hir()`.

Author: bors

compiler/rustc_driver/src/pretty.rs

@@ -489,7 +489,7 @@ fn print_with_analysis(
             let mut out = String::new();
             abort_on_err(rustc_typeck::check_crate(tcx), tcx.sess);
             debug!("pretty printing THIR tree");
-            for did in tcx.body_owners() {
+            for did in tcx.hir().body_owners() {
                 let _ = writeln!(
                     out,
                     "{:?}:\n{}\n",

compiler/rustc_hir/src/hir.rs

@@ -1,7 +1,7 @@
 use crate::def::{CtorKind, DefKind, Res};
 use crate::def_id::{DefId, CRATE_DEF_ID};
 crate use crate::hir_id::{HirId, ItemLocalId};
-use crate::{itemlikevisit, LangItem};
+use crate::LangItem;
 
 use rustc_ast::util::parser::ExprPrecedence;
 use rustc_ast::{self as ast, CrateSugar, LlvmAsmDialect};
@@ -10,7 +10,6 @@ pub use rustc_ast::{BorrowKind, ImplPolarity, IsAuto};
 pub use rustc_ast::{CaptureBy, Movability, Mutability};
 use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece};
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
 use rustc_index::vec::IndexVec;
 use rustc_macros::HashStable_Generic;
 use rustc_span::source_map::Spanned;
@@ -708,52 +707,6 @@ impl Crate<'hir> {
     }
 }
 
-impl Crate<'_> {
-    /// Visits all items in the crate in some deterministic (but
-    /// unspecified) order. If you just need to process every item,
-    /// but don't care about nesting, this method is the best choice.
-    ///
-    /// If you do care about nesting -- usually because your algorithm
-    /// follows lexical scoping rules -- then you want a different
-    /// approach. You should override `visit_nested_item` in your
-    /// visitor and then call `intravisit::walk_crate` instead.
-    pub fn visit_all_item_likes<'hir, V>(&'hir self, visitor: &mut V)
-    where
-        V: itemlikevisit::ItemLikeVisitor<'hir>,
-    {
-        for owner in self.owners.iter().filter_map(Option::as_ref) {
-            match owner {
-                OwnerNode::Item(item) => visitor.visit_item(item),
-                OwnerNode::ForeignItem(item) => visitor.visit_foreign_item(item),
-                OwnerNode::ImplItem(item) => visitor.visit_impl_item(item),
-                OwnerNode::TraitItem(item) => visitor.visit_trait_item(item),
-                OwnerNode::Crate(_) => {}
-            }
-        }
-    }
-
-    /// A parallel version of `visit_all_item_likes`.
-    pub fn par_visit_all_item_likes<'hir, V>(&'hir self, visitor: &V)
-    where
-        V: itemlikevisit::ParItemLikeVisitor<'hir> + Sync + Send,
-    {
-        par_for_each_in(&self.owners.raw, |owner| match owner {
-            Some(OwnerNode::Item(item)) => visitor.visit_item(item),
-            Some(OwnerNode::ForeignItem(item)) => visitor.visit_foreign_item(item),
-            Some(OwnerNode::ImplItem(item)) => visitor.visit_impl_item(item),
-            Some(OwnerNode::TraitItem(item)) => visitor.visit_trait_item(item),
-            Some(OwnerNode::Crate(_)) | None => {}
-        })
-    }
-
-    pub fn items<'hir>(&'hir self) -> impl Iterator<Item = &'hir Item<'hir>> + 'hir {
-        self.owners.iter().filter_map(|owner| match owner {
-            Some(OwnerNode::Item(item)) => Some(*item),
-            _ => None,
-        })
-    }
-}
-
 /// A block of statements `{ .. }`, which may have a label (in this case the
 /// `targeted_by_break` field will be `true`) and may be `unsafe` by means of
 /// the `rules` being anything but `DefaultBlock`.

compiler/rustc_hir_pretty/src/lib.rs

@@ -51,19 +51,6 @@ pub struct NoAnn;
 impl PpAnn for NoAnn {}
 pub const NO_ANN: &dyn PpAnn = &NoAnn;
 
-impl PpAnn for hir::Crate<'_> {
-    fn nested(&self, state: &mut State<'_>, nested: Nested) {
-        match nested {
-            Nested::Item(id) => state.print_item(self.item(id)),
-            Nested::TraitItem(id) => state.print_trait_item(self.trait_item(id)),
-            Nested::ImplItem(id) => state.print_impl_item(self.impl_item(id)),
-            Nested::ForeignItem(id) => state.print_foreign_item(self.foreign_item(id)),
-            Nested::Body(id) => state.print_expr(&self.body(id).value),
-            Nested::BodyParamPat(id, i) => state.print_pat(&self.body(id).params[i].pat),
-        }
-    }
-}
-
 /// Identical to the `PpAnn` implementation for `hir::Crate`,
 /// except it avoids creating a dependency on the whole crate.
 impl PpAnn for &dyn rustc_hir::intravisit::Map<'_> {

compiler/rustc_incremental/src/assert_dep_graph.rs

@@ -74,7 +74,7 @@ pub fn assert_dep_graph(tcx: TyCtxt<'_>) {
             let mut visitor =
                 IfThisChanged { tcx, if_this_changed: vec![], then_this_would_need: vec![] };
             visitor.process_attrs(hir::CRATE_HIR_ID);
-            tcx.hir().krate().visit_all_item_likes(&mut visitor.as_deep_visitor());
+            tcx.hir().visit_all_item_likes(&mut visitor.as_deep_visitor());
             (visitor.if_this_changed, visitor.then_this_would_need)
         };
 

compiler/rustc_incremental/src/persist/dirty_clean.rs

@@ -137,9 +137,8 @@ pub fn check_dirty_clean_annotations(tcx: TyCtxt<'_>) {
     }
 
     tcx.dep_graph.with_ignore(|| {
-        let krate = tcx.hir().krate();
         let mut dirty_clean_visitor = DirtyCleanVisitor { tcx, checked_attrs: Default::default() };
-        krate.visit_all_item_likes(&mut dirty_clean_visitor);
+        tcx.hir().visit_all_item_likes(&mut dirty_clean_visitor);
 
         let mut all_attrs = FindAllAttrs { tcx, found_attrs: vec![] };
         tcx.hir().walk_attributes(&mut all_attrs);

compiler/rustc_interface/src/passes.rs

@@ -886,9 +886,7 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
         parallel!(
             {
                 sess.time("match_checking", || {
-                    tcx.par_body_owners(|def_id| {
-                        tcx.ensure().check_match(def_id.to_def_id());
-                    });
+                    tcx.hir().par_body_owners(|def_id| tcx.ensure().check_match(def_id.to_def_id()))
                 });
             },
             {
@@ -907,11 +905,11 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
     });
 
     sess.time("MIR_borrow_checking", || {
-        tcx.par_body_owners(|def_id| tcx.ensure().mir_borrowck(def_id));
+        tcx.hir().par_body_owners(|def_id| tcx.ensure().mir_borrowck(def_id));
     });
 
     sess.time("MIR_effect_checking", || {
-        for def_id in tcx.body_owners() {
+        for def_id in tcx.hir().body_owners() {
             tcx.ensure().thir_check_unsafety(def_id);
             if !tcx.sess.opts.debugging_opts.thir_unsafeck {
                 rustc_mir_transform::check_unsafety::check_unsafety(tcx, def_id);

compiler/rustc_interface/src/proc_macro_decls.rs

@@ -7,7 +7,7 @@ use rustc_span::symbol::sym;
 
 fn proc_macro_decls_static(tcx: TyCtxt<'_>, (): ()) -> Option<LocalDefId> {
     let mut finder = Finder { tcx, decls: None };
-    tcx.hir().krate().visit_all_item_likes(&mut finder);
+    tcx.hir().visit_all_item_likes(&mut finder);
 
     finder.decls.map(|id| tcx.hir().local_def_id(id))
 }

compiler/rustc_lint/src/builtin.rs

@@ -584,8 +584,14 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
         self.doc_hidden_stack.pop().expect("empty doc_hidden_stack");
     }
 
-    fn check_crate(&mut self, cx: &LateContext<'_>, krate: &hir::Crate<'_>) {
-        self.check_missing_docs_attrs(cx, CRATE_DEF_ID, krate.module().inner, "the", "crate");
+    fn check_crate(&mut self, cx: &LateContext<'_>) {
+        self.check_missing_docs_attrs(
+            cx,
+            CRATE_DEF_ID,
+            cx.tcx.def_span(CRATE_DEF_ID),
+            "the",
+            "crate",
+        );
     }
 
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {

compiler/rustc_lint/src/late.rs

@@ -430,8 +430,6 @@ pub fn late_lint_mod<'tcx, T: LateLintPass<'tcx>>(
 fn late_lint_pass_crate<'tcx, T: LateLintPass<'tcx>>(tcx: TyCtxt<'tcx>, pass: T) {
     let access_levels = &tcx.privacy_access_levels(());
 
-    let krate = tcx.hir().krate();
-
     let context = LateContext {
         tcx,
         enclosing_body: None,
@@ -450,10 +448,10 @@ fn late_lint_pass_crate<'tcx, T: LateLintPass<'tcx>>(tcx: TyCtxt<'tcx>, pass: T)
     cx.with_lint_attrs(hir::CRATE_HIR_ID, |cx| {
         // since the root module isn't visited as an item (because it isn't an
         // item), warn for it here.
-        lint_callback!(cx, check_crate, krate);
+        lint_callback!(cx, check_crate,);
         tcx.hir().walk_toplevel_module(cx);
         tcx.hir().walk_attributes(cx);
-        lint_callback!(cx, check_crate_post, krate);
+        lint_callback!(cx, check_crate_post,);
     })
 }
 

compiler/rustc_lint/src/passes.rs

@@ -16,8 +16,8 @@ macro_rules! late_lint_methods {
             fn check_body(a: &$hir hir::Body<$hir>);
             fn check_body_post(a: &$hir hir::Body<$hir>);
             fn check_name(a: Span, b: Symbol);
-            fn check_crate(a: &$hir hir::Crate<$hir>);
-            fn check_crate_post(a: &$hir hir::Crate<$hir>);
+            fn check_crate();
+            fn check_crate_post();
             fn check_mod(a: &$hir hir::Mod<$hir>, b: Span, c: hir::HirId);
             fn check_mod_post(a: &$hir hir::Mod<$hir>, b: Span, c: hir::HirId);
             fn check_foreign_item(a: &$hir hir::ForeignItem<$hir>);

compiler/rustc_metadata/src/foreign_modules.rs

@@ -5,7 +5,7 @@ use rustc_middle::ty::TyCtxt;
 
 crate fn collect(tcx: TyCtxt<'_>) -> Vec<ForeignModule> {
     let mut collector = Collector { modules: Vec::new() };
-    tcx.hir().krate().visit_all_item_likes(&mut collector);
+    tcx.hir().visit_all_item_likes(&mut collector);
     collector.modules
 }
 

compiler/rustc_metadata/src/native_libs.rs

@@ -14,7 +14,7 @@ use rustc_target::spec::abi::Abi;
 
 crate fn collect(tcx: TyCtxt<'_>) -> Vec<NativeLib> {
     let mut collector = Collector { tcx, libs: Vec::new() };
-    tcx.hir().krate().visit_all_item_likes(&mut collector);
+    tcx.hir().visit_all_item_likes(&mut collector);
     collector.process_command_line();
     collector.libs
 }

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -440,16 +440,15 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
     }
 
     fn encode_info_for_items(&mut self) {
-        let krate = self.tcx.hir().krate();
-        self.encode_info_for_mod(CRATE_DEF_ID, krate.module());
+        self.encode_info_for_mod(CRATE_DEF_ID, self.tcx.hir().root_module());
 
         // Proc-macro crates only export proc-macro items, which are looked
         // up using `proc_macro_data`
         if self.is_proc_macro {
             return;
         }
 
-        krate.visit_all_item_likes(&mut self.as_deep_visitor());
+        self.tcx.hir().visit_all_item_likes(&mut self.as_deep_visitor());
     }
 
     fn encode_def_path_table(&mut self) {
@@ -1782,7 +1781,7 @@ impl EncodeContext<'a, 'tcx> {
         debug!("EncodeContext::encode_impls()");
         let tcx = self.tcx;
         let mut visitor = ImplVisitor { tcx, impls: FxHashMap::default() };
-        tcx.hir().krate().visit_all_item_likes(&mut visitor);
+        tcx.hir().visit_all_item_likes(&mut visitor);
 
         let mut all_impls: Vec<_> = visitor.impls.into_iter().collect();
 

compiler/rustc_middle/src/hir/map/mod.rs

@@ -6,6 +6,7 @@ use rustc_ast as ast;
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::svh::Svh;
+use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, CRATE_DEF_ID, LOCAL_CRATE};
 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash};
@@ -156,6 +157,21 @@ impl<'hir> Map<'hir> {
         self.tcx.hir_crate(())
     }
 
+    pub fn root_module(&self) -> &'hir Mod<'hir> {
+        match self.tcx.hir_owner(CRATE_DEF_ID).map(|o| o.node) {
+            Some(OwnerNode::Crate(item)) => item,
+            _ => bug!(),
+        }
+    }
+
+    pub fn items(&self) -> impl Iterator<Item = &'hir Item<'hir>> + 'hir {
+        let krate = self.krate();
+        krate.owners.iter().filter_map(|owner| match owner.as_ref()? {
+            OwnerNode::Item(item) => Some(*item),
+            _ => None,
+        })
+    }
+
     pub fn def_key(&self, def_id: LocalDefId) -> DefKey {
         // Accessing the DefKey is ok, since it is part of DefPathHash.
         self.tcx.untracked_resolutions.definitions.def_key(def_id)
@@ -475,6 +491,17 @@ impl<'hir> Map<'hir> {
         Some(ccx)
     }
 
+    /// Returns an iterator of the `DefId`s for all body-owners in this
+    /// crate. If you would prefer to iterate over the bodies
+    /// themselves, you can do `self.hir().krate().body_ids.iter()`.
+    pub fn body_owners(self) -> impl Iterator<Item = LocalDefId> + 'hir {
+        self.krate().bodies.keys().map(move |&body_id| self.body_owner_def_id(body_id))
+    }
+
+    pub fn par_body_owners<F: Fn(LocalDefId) + Sync + Send>(self, f: F) {
+        par_for_each_in(&self.krate().bodies, |(&body_id, _)| f(self.body_owner_def_id(body_id)));
+    }
+
     pub fn ty_param_owner(&self, id: HirId) -> HirId {
         match self.get(id) {
             Node::Item(&Item { kind: ItemKind::Trait(..) | ItemKind::TraitAlias(..), .. }) => id,
@@ -531,6 +558,45 @@ impl<'hir> Map<'hir> {
         }
     }
 
+    /// Visits all items in the crate in some deterministic (but
+    /// unspecified) order. If you just need to process every item,
+    /// but don't care about nesting, this method is the best choice.
+    ///
+    /// If you do care about nesting -- usually because your algorithm
+    /// follows lexical scoping rules -- then you want a different
+    /// approach. You should override `visit_nested_item` in your
+    /// visitor and then call `intravisit::walk_crate` instead.
+    pub fn visit_all_item_likes<V>(&self, visitor: &mut V)
+    where
+        V: itemlikevisit::ItemLikeVisitor<'hir>,
+    {
+        let krate = self.krate();
+        for owner in krate.owners.iter().filter_map(Option::as_ref) {
+            match owner {
+                OwnerNode::Item(item) => visitor.visit_item(item),
+                OwnerNode::ForeignItem(item) => visitor.visit_foreign_item(item),
+                OwnerNode::ImplItem(item) => visitor.visit_impl_item(item),
+                OwnerNode::TraitItem(item) => visitor.visit_trait_item(item),
+                OwnerNode::Crate(_) => {}
+            }
+        }
+    }
+
+    /// A parallel version of `visit_all_item_likes`.
+    pub fn par_visit_all_item_likes<V>(&self, visitor: &V)
+    where
+        V: itemlikevisit::ParItemLikeVisitor<'hir> + Sync + Send,
+    {
+        let krate = self.krate();
+        par_for_each_in(&krate.owners.raw, |owner| match owner.as_ref() {
+            Some(OwnerNode::Item(item)) => visitor.visit_item(item),
+            Some(OwnerNode::ForeignItem(item)) => visitor.visit_foreign_item(item),
+            Some(OwnerNode::ImplItem(item)) => visitor.visit_impl_item(item),
+            Some(OwnerNode::TraitItem(item)) => visitor.visit_trait_item(item),
+            Some(OwnerNode::Crate(_)) | None => {}
+        })
+    }
+
     pub fn visit_item_likes_in_module<V>(&self, module: LocalDefId, visitor: &mut V)
     where
         V: ItemLikeVisitor<'hir>,

compiler/rustc_middle/src/ty/mod.rs

@@ -29,10 +29,8 @@ use crate::ty::subst::{GenericArg, InternalSubsts, Subst, SubstsRef};
 use crate::ty::util::Discr;
 use rustc_ast as ast;
 use rustc_attr as attr;
-use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
-use rustc_data_structures::sync::{self, par_iter, ParallelIterator};
 use rustc_data_structures::tagged_ptr::CopyTaggedPtr;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
@@ -1696,18 +1694,6 @@ impl<'tcx> TyCtxt<'tcx> {
         self.typeck(self.hir().body_owner_def_id(body))
     }
 
-    /// Returns an iterator of the `DefId`s for all body-owners in this
-    /// crate. If you would prefer to iterate over the bodies
-    /// themselves, you can do `self.hir().krate().body_ids.iter()`.
-    pub fn body_owners(self) -> impl Iterator<Item = LocalDefId> + Captures<'tcx> + 'tcx {
-        self.hir().krate().bodies.keys().map(move |&body_id| self.hir().body_owner_def_id(body_id))
-    }
-
-    pub fn par_body_owners<F: Fn(LocalDefId) + sync::Sync + sync::Send>(self, f: F) {
-        par_iter(&self.hir().krate().bodies)
-            .for_each(|(&body_id, _)| f(self.hir().body_owner_def_id(body_id)));
-    }
-
     pub fn provided_trait_methods(self, id: DefId) -> impl 'tcx + Iterator<Item = &'tcx AssocItem> {
         self.associated_items(id)
             .in_definition_order()

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -2340,7 +2340,7 @@ define_print_and_forward_display! {
 fn for_each_def(tcx: TyCtxt<'_>, mut collect_fn: impl for<'b> FnMut(&'b Ident, Namespace, DefId)) {
     // Iterate all local crate items no matter where they are defined.
     let hir = tcx.hir();
-    for item in hir.krate().items() {
+    for item in hir.items() {
         if item.ident.name.as_str().is_empty() || matches!(item.kind, ItemKind::Use(_, _)) {
             continue;
         }