Auto merge of rust-lang#135771 - GuillaumeGomez:jump-to-def-perf, r=<try>

[PERF for "jump to def"] Re-enable "jump to def" feature on rustc docs

This PR is NOT meant to be merged. `@fmease` and I are using it to check perfs on the "jump to def" feature.

Used for rust-lang#135485.

r? `@fmease`

Author: bors

compiler/rustc_interface/src/passes.rs

@@ -827,7 +827,7 @@ fn run_required_analyses(tcx: TyCtxt<'_>) {
     if tcx.sess.opts.unstable_opts.input_stats {
         rustc_passes::input_stats::print_hir_stats(tcx);
     }
-    #[cfg(debug_assertions)]
+    #[cfg(all(not(doc), debug_assertions))]
     rustc_passes::hir_id_validator::check_crate(tcx);
     let sess = tcx.sess;
     sess.time("misc_checking_1", || {

src/bootstrap/src/core/build_steps/doc.rs

@@ -845,6 +845,9 @@ impl Step for Rustc {
         cargo.rustdocflag("--extern-html-root-url");
         cargo.rustdocflag("ena=https://docs.rs/ena/latest/");
 
+        // Enabling the "jump to def" feature on rustc's source code pages.
+        cargo.rustdocflag("--generate-link-to-definition");
+
         let mut to_open = None;
 
         let out_dir = builder.stage_out(compiler, Mode::Rustc).join(target).join("doc");

src/librustdoc/html/render/span_map.rs

@@ -4,7 +4,7 @@ use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_hir::intravisit::{self, Visitor};
-use rustc_hir::{ExprKind, HirId, Item, ItemKind, Mod, Node, Pat, PatKind, QPath};
+use rustc_hir::{ExprKind, HirId, Item, ItemKind, Mod, Node, QPath};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::hygiene::MacroKind;
@@ -189,27 +189,6 @@ impl SpanMapVisitor<'_> {
             self.matches.insert(span, link);
         }
     }
-
-    fn handle_pat(&mut self, p: &Pat<'_>) {
-        match p.kind {
-            PatKind::Binding(_, _, _, Some(p)) => self.handle_pat(p),
-            PatKind::Struct(qpath, _, _)
-            | PatKind::TupleStruct(qpath, _, _)
-            | PatKind::Path(qpath) => match qpath {
-                QPath::TypeRelative(_, path) if matches!(path.res, Res::Err) => {
-                    self.infer_id(path.hir_id, Some(p.hir_id), qpath.span());
-                }
-                QPath::Resolved(_, path) => self.handle_path(path),
-                _ => {}
-            },
-            PatKind::Or(pats) => {
-                for pat in pats {
-                    self.handle_pat(pat);
-                }
-            }
-            _ => {}
-        }
-    }
 }
 
 impl<'tcx> Visitor<'tcx> for SpanMapVisitor<'tcx> {
@@ -227,8 +206,36 @@ impl<'tcx> Visitor<'tcx> for SpanMapVisitor<'tcx> {
         intravisit::walk_path(self, path);
     }
 
-    fn visit_pat(&mut self, p: &Pat<'tcx>) {
-        self.handle_pat(p);
+    fn visit_qpath(&mut self, qpath: &QPath<'tcx>, id: HirId, span: Span) {
+        match *qpath {
+            QPath::TypeRelative(qself, path) => {
+                if matches!(path.res, Res::Err) {
+                    let tcx = self.tcx;
+                    let hir = tcx.hir();
+                    let body_id = hir.enclosing_body_owner(id);
+                    let typeck_results = tcx.typeck_body(hir.body_owned_by(body_id).id());
+                    let path = rustc_hir::Path {
+                        // We change the span to not include parens.
+                        span: span.with_hi(path.ident.span.hi()),
+                        res: typeck_results.qpath_res(qpath, id),
+                        segments: &[],
+                    };
+                    self.handle_path(&path);
+                } else {
+                    self.infer_id(path.hir_id, Some(id), span);
+                }
+
+                rustc_ast::visit::try_visit!(self.visit_ty(qself));
+                self.visit_path_segment(path);
+            }
+            QPath::Resolved(maybe_qself, path) => {
+                self.handle_path(path);
+
+                rustc_ast::visit::visit_opt!(self, visit_ty, maybe_qself);
+                self.visit_path(path, id)
+            }
+            _ => {}
+        }
     }
 
     fn visit_mod(&mut self, m: &'tcx Mod<'tcx>, span: Span, id: HirId) {

tests/rustdoc/jump-to-def-assoc-items.rs

@@ -0,0 +1,15 @@
+//@ compile-flags: -Zunstable-options --generate-link-to-definition
+
+#![crate_name = "foo"]
+
+pub enum Ty {
+    Var,
+}
+
+//@ has 'src/foo/jump-to-def-assoc-items.rs.html'
+//@ has - '//a[@href="#6"]' 'Self::Var'
+impl Ty {
+    fn f() {
+        let _ = Self::Var;
+    }
+}