Auto merge of #118086 - nnethercote:queries-cleanups, r=bjorn3

Queries cleanups

r? `@bjorn3`

compiler/rustc_driver_impl/src/lib.rs

@@ -360,8 +360,8 @@ fn run_compiler(
     drop(default_handler);
 
     interface::run_compiler(config, |compiler| {
-        let sess = compiler.session();
+        let sess = &compiler.sess;
-        let codegen_backend = compiler.codegen_backend();
+        let codegen_backend = &*compiler.codegen_backend;
 
         // This implements `-Whelp`. It should be handled very early, like
         // `--help`/`-Zhelp`/`-Chelp`. This is the earliest it can run, because
@@ -453,8 +453,10 @@ fn run_compiler(
                 return early_exit();
             }
 
-            let ongoing_codegen = queries.ongoing_codegen()?;
+            let linker = queries.codegen_and_build_linker()?;
 
+            // This must run after monomorphization so that all generic types
+            // have been instantiated.
             if sess.opts.unstable_opts.print_type_sizes {
                 sess.code_stats.print_type_sizes();
             }
@@ -465,10 +467,11 @@ fn run_compiler(
                 sess.code_stats.print_vtable_sizes(crate_name);
             }
 
-            let linker = queries.linker(ongoing_codegen)?;
             Ok(Some(linker))
         })?;
 
+        // Linking is done outside the `compiler.enter()` so that the
+        // `GlobalCtxt` within `Queries` can be freed as early as possible.
         if let Some(linker) = linker {
             let _timer = sess.timer("link");
             linker.link(sess, codegen_backend)?
@@ -668,7 +671,7 @@ fn process_rlink(sess: &Session, compiler: &interface::Compiler) {
                 };
             }
         };
-        let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
+        let result = compiler.codegen_backend.link(sess, codegen_results, &outputs);
         abort_on_err(result, sess);
     } else {
         sess.emit_fatal(RlinkNotAFile {})

compiler/rustc_interface/src/interface.rs

@@ -38,18 +38,12 @@ pub type Result<T> = result::Result<T, ErrorGuaranteed>;
 /// Can be used to run `rustc_interface` queries.
 /// Created by passing [`Config`] to [`run_compiler`].
 pub struct Compiler {
-    sess: Session,
+    pub sess: Session,
-    codegen_backend: Box<dyn CodegenBackend>,
+    pub codegen_backend: Box<dyn CodegenBackend>,
     pub(crate) override_queries: Option<fn(&Session, &mut Providers)>,
 }
 
 impl Compiler {
-    pub fn session(&self) -> &Session {
-        &self.sess
-    }
-    pub fn codegen_backend(&self) -> &dyn CodegenBackend {
-        &*self.codegen_backend
-    }
     pub fn build_output_filenames(
         &self,
         sess: &Session,

compiler/rustc_interface/src/passes.rs

@@ -645,10 +645,10 @@ pub fn create_global_ctxt<'tcx>(
     // incr. comp. yet.
     dep_graph.assert_ignored();
 
-    let sess = &compiler.session();
+    let sess = &compiler.sess;
     let query_result_on_disk_cache = rustc_incremental::load_query_result_cache(sess);
 
-    let codegen_backend = compiler.codegen_backend();
+    let codegen_backend = &compiler.codegen_backend;
     let mut providers = *DEFAULT_QUERY_PROVIDERS;
     codegen_backend.provide(&mut providers);
 

compiler/rustc_interface/src/queries.rs

@@ -17,7 +17,8 @@ use rustc_middle::dep_graph::DepGraph;
 use rustc_middle::ty::{GlobalCtxt, TyCtxt};
 use rustc_session::config::{self, CrateType, OutputFilenames, OutputType};
 use rustc_session::cstore::Untracked;
-use rustc_session::{output::find_crate_name, Session};
+use rustc_session::output::find_crate_name;
+use rustc_session::Session;
 use rustc_span::symbol::sym;
 use std::any::Any;
 use std::cell::{RefCell, RefMut};
@@ -101,17 +102,10 @@ impl<'tcx> Queries<'tcx> {
         }
     }
 
-    fn session(&self) -> &Session {
-        self.compiler.session()
-    }
-
-    fn codegen_backend(&self) -> &dyn CodegenBackend {
-        self.compiler.codegen_backend()
-    }
-
     pub fn parse(&self) -> Result<QueryResult<'_, ast::Crate>> {
-        self.parse
+        self.parse.compute(|| {
-            .compute(|| passes::parse(self.session()).map_err(|mut parse_error| parse_error.emit()))
+            passes::parse(&self.compiler.sess).map_err(|mut parse_error| parse_error.emit())
+        })
     }
 
     #[deprecated = "pre_configure may be made private in the future. If you need it please open an issue with your use case."]
@@ -119,7 +113,7 @@ impl<'tcx> Queries<'tcx> {
         self.pre_configure.compute(|| {
             let mut krate = self.parse()?.steal();
 
-            let sess = self.session();
+            let sess = &self.compiler.sess;
             rustc_builtin_macros::cmdline_attrs::inject(
                 &mut krate,
                 &sess.parse_sess,
@@ -134,7 +128,7 @@ impl<'tcx> Queries<'tcx> {
 
     pub fn global_ctxt(&'tcx self) -> Result<QueryResult<'_, &'tcx GlobalCtxt<'tcx>>> {
         self.gcx.compute(|| {
-            let sess = self.session();
+            let sess = &self.compiler.sess;
             #[allow(deprecated)]
             let (krate, pre_configured_attrs) = self.pre_configure()?.steal();
 
@@ -150,7 +144,7 @@ impl<'tcx> Queries<'tcx> {
             let dep_graph = setup_dep_graph(sess, crate_name, stable_crate_id)?;
 
             let cstore = FreezeLock::new(Box::new(CStore::new(
-                self.codegen_backend().metadata_loader(),
+                self.compiler.codegen_backend.metadata_loader(),
                 stable_crate_id,
             )) as _);
             let definitions = FreezeLock::new(Definitions::new(stable_crate_id));
@@ -186,22 +180,6 @@ impl<'tcx> Queries<'tcx> {
         })
     }
 
-    pub fn ongoing_codegen(&'tcx self) -> Result<Box<dyn Any>> {
-        self.global_ctxt()?.enter(|tcx| {
-            // Don't do code generation if there were any errors
-            self.session().compile_status()?;
-
-            // If we have any delayed bugs, for example because we created TyKind::Error earlier,
-            // it's likely that codegen will only cause more ICEs, obscuring the original problem
-            self.session().diagnostic().flush_delayed();
-
-            // Hook for UI tests.
-            Self::check_for_rustc_errors_attr(tcx);
-
-            Ok(passes::start_codegen(self.codegen_backend(), tcx))
-        })
-    }
-
     /// Check for the `#[rustc_error]` annotation, which forces an error in codegen. This is used
     /// to write UI tests that actually test that compilation succeeds without reporting
     /// an error.
@@ -236,8 +214,20 @@ impl<'tcx> Queries<'tcx> {
         }
     }
 
-    pub fn linker(&'tcx self, ongoing_codegen: Box<dyn Any>) -> Result<Linker> {
+    pub fn codegen_and_build_linker(&'tcx self) -> Result<Linker> {
         self.global_ctxt()?.enter(|tcx| {
+            // Don't do code generation if there were any errors
+            self.compiler.sess.compile_status()?;
+
+            // If we have any delayed bugs, for example because we created TyKind::Error earlier,
+            // it's likely that codegen will only cause more ICEs, obscuring the original problem
+            self.compiler.sess.diagnostic().flush_delayed();
+
+            // Hook for UI tests.
+            Self::check_for_rustc_errors_attr(tcx);
+
+            let ongoing_codegen = passes::start_codegen(&*self.compiler.codegen_backend, tcx);
+
             Ok(Linker {
                 dep_graph: tcx.dep_graph.clone(),
                 output_filenames: tcx.output_filenames(()).clone(),
@@ -304,6 +294,7 @@ impl Compiler {
     where
         F: for<'tcx> FnOnce(&'tcx Queries<'tcx>) -> T,
     {
+        // Must declare `_timer` first so that it is dropped after `queries`.
         let mut _timer = None;
         let queries = Queries::new(self);
         let ret = f(&queries);
@@ -316,15 +307,16 @@ impl Compiler {
             // 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");
+                    queries.compiler.sess.prof.generic_activity("self_profile_alloc_query_strings");
                 gcx.enter(rustc_query_impl::alloc_self_profile_query_strings);
             }
 
-            self.session()
+            self.sess.time("serialize_dep_graph", || gcx.enter(rustc_incremental::save_dep_graph));
-                .time("serialize_dep_graph", || gcx.enter(rustc_incremental::save_dep_graph));
         }
 
-        _timer = Some(self.session().timer("free_global_ctxt"));
+        // The timer's lifetime spans the dropping of `queries`, which contains
+        // the global context.
+        _timer = Some(self.sess.timer("free_global_ctxt"));
 
         ret
     }

src/librustdoc/doctest.rs

@@ -127,17 +127,17 @@ pub(crate) fn run(options: RustdocOptions) -> Result<(), ErrorGuaranteed> {
                         options,
                         false,
                         opts,
-                        Some(compiler.session().parse_sess.clone_source_map()),
+                        Some(compiler.sess.parse_sess.clone_source_map()),
                         None,
                         enable_per_target_ignores,
                     );
 
                     let mut hir_collector = HirCollector {
-                        sess: compiler.session(),
+                        sess: &compiler.sess,
                         collector: &mut collector,
                         map: tcx.hir(),
                         codes: ErrorCodes::from(
-                            compiler.session().opts.unstable_features.is_nightly_build(),
+                            compiler.sess.opts.unstable_features.is_nightly_build(),
                         ),
                         tcx,
                     };
@@ -150,7 +150,7 @@ pub(crate) fn run(options: RustdocOptions) -> Result<(), ErrorGuaranteed> {
 
                     collector
                 });
-                if compiler.session().diagnostic().has_errors_or_lint_errors().is_some() {
+                if compiler.sess.diagnostic().has_errors_or_lint_errors().is_some() {
                     FatalError.raise();
                 }
 

src/librustdoc/lib.rs

@@ -794,7 +794,7 @@ fn main_args(
     let config = core::create_config(options, &render_options, using_internal_features);
 
     interface::run_compiler(config, |compiler| {
-        let sess = compiler.session();
+        let sess = &compiler.sess;
 
         if sess.opts.describe_lints {
             rustc_driver::describe_lints(sess);

tests/run-make-fulldeps/issue-19371/foo.rs

@@ -69,9 +69,8 @@ fn compile(code: String, output: PathBuf, sysroot: PathBuf) {
     interface::run_compiler(config, |compiler| {
         let linker = compiler.enter(|queries| {
             queries.global_ctxt()?.enter(|tcx| tcx.analysis(()))?;
-            let ongoing_codegen = queries.ongoing_codegen()?;
+            queries.codegen_and_build_linker()
-            queries.linker(ongoing_codegen)
         });
-        linker.unwrap().link(compiler.session(), compiler.codegen_backend()).unwrap();
+        linker.unwrap().link(&compiler.sess, &*compiler.codegen_backend).unwrap();
     });
 }

tests/run-make-fulldeps/obtain-borrowck/driver.rs

@@ -61,7 +61,7 @@ impl rustc_driver::Callbacks for CompilerCalls {
         compiler: &Compiler,
         queries: &'tcx Queries<'tcx>,
     ) -> Compilation {
-        compiler.session().abort_if_errors();
+        compiler.sess.abort_if_errors();
         queries.global_ctxt().unwrap().enter(|tcx| {
             // Collect definition ids of MIR bodies.
             let hir = tcx.hir();