Calculate self-profile strings in `Compiler::enter` instead in codegen

This avoids each tool having to separately find and call
`self_profile_alloc_strings`.

- Don't compute the global context if it hasn't yet been computed

  This avoids giving extraneous errors about unresolved names if an error
  occurs during parsing.

2 files changed, 13 insertions, 10 deletions

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index ead2512d3b2..7031234e108 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -1017,13 +1017,6 @@ pub fn start_codegen<'tcx>(
     tcx.sess.time("assert_dep_graph", || rustc_incremental::assert_dep_graph(tcx));
     tcx.sess.time("serialize_dep_graph", || rustc_incremental::save_dep_graph(tcx));
 
-    // We assume that no queries are run past here. If there are new queries
-    // after this point, they'll show up as "<unknown>" in self-profiling data.
-    {
-        let _prof_timer = tcx.prof.generic_activity("self_profile_alloc_query_strings");
-        tcx.alloc_self_profile_query_strings();
-    }
-
     info!("Post-codegen\n{:?}", tcx.debug_stats());
 
     if tcx.sess.opts.output_types.contains_key(&OutputType::Mir) {
diff --git a/compiler/rustc_interface/src/queries.rs b/compiler/rustc_interface/src/queries.rs
index 9c49f926d41..ac6b6d03115 100644
--- a/compiler/rustc_interface/src/queries.rs
+++ b/compiler/rustc_interface/src/queries.rs
@@ -417,9 +417,19 @@ impl Compiler {
         let queries = Queries::new(&self);
         let ret = f(&queries);
 
-        if self.session().opts.debugging_opts.query_stats {
-            if let Ok(gcx) = queries.global_ctxt() {
-                gcx.peek_mut().print_stats();
+        // NOTE: intentionally does not compute the global context if it hasn't been built yet,
+        // since that likely means there was a parse error.
+        if let Some(Ok(gcx)) = &mut *queries.global_ctxt.result.borrow_mut() {
+            // We assume that no queries are run past here. If there are new queries
+            // after this point, they'll show up as "<unknown>" in self-profiling data.
+            {
+                let _prof_timer =
+                    queries.session().prof.generic_activity("self_profile_alloc_query_strings");
+                gcx.enter(|tcx| tcx.alloc_self_profile_query_strings());
+            }
+
+            if self.session().opts.debugging_opts.query_stats {
+                gcx.print_stats();
             }
         }