Move the resolver into a query

Author: oli-obk

compiler/rustc_codegen_ssa/src/back/metadata.rs

@@ -33,6 +33,7 @@ use rustc_target::spec::{RelocModel, Target};
 /// <dt>dylib</dt>
 /// <dd>The metadata can be found in the `.rustc` section of the shared library.</dd>
 /// </dl>
+#[derive(Debug)]
 pub struct DefaultMetadataLoader;
 
 fn load_metadata_with(

compiler/rustc_driver_impl/src/lib.rs

@@ -320,7 +320,7 @@ fn run_compiler(
             }
 
             // Make sure name resolution and macro expansion is run.
-            queries.global_ctxt()?;
+            queries.global_ctxt()?.enter(|tcx| tcx.resolver_for_lowering(()));
 
             if callbacks.after_expansion(compiler, queries) == Compilation::Stop {
                 return early_exit();

compiler/rustc_interface/src/passes.rs

@@ -8,6 +8,7 @@ use rustc_ast::{self as ast, visit};
 use rustc_borrowck as mir_borrowck;
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_data_structures::parallel;
+use rustc_data_structures::steal::Steal;
 use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
 use rustc_errors::PResult;
 use rustc_expand::base::{ExtCtxt, LintStoreExpand, ResolverExpand};
@@ -172,7 +173,7 @@ impl LintStoreExpand for LintStoreExpandImpl<'_> {
 /// harness if one is to be provided, injection of a dependency on the
 /// standard library and prelude, and name resolution.
 #[instrument(level = "trace", skip(tcx, krate, resolver))]
-pub fn configure_and_expand(
+fn configure_and_expand(
     tcx: TyCtxt<'_>,
     mut krate: ast::Crate,
     resolver: &mut Resolver<'_, '_>,
@@ -564,6 +565,34 @@ fn write_out_deps(
     }
 }
 
+fn resolver_for_lowering<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    (): (),
+) -> &'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)> {
+    let arenas = Resolver::arenas();
+    let krate = tcx.crate_for_resolver(()).steal();
+    let mut resolver = Resolver::new(
+        tcx,
+        &krate,
+        tcx.crate_name(LOCAL_CRATE),
+        tcx.metadata_loader(()).steal(),
+        &arenas,
+    );
+    let krate = configure_and_expand(tcx, krate, &mut resolver);
+
+    // Make sure we don't mutate the cstore from here on.
+    tcx.untracked().cstore.leak();
+
+    let ty::ResolverOutputs {
+        global_ctxt: untracked_resolutions,
+        ast_lowering: untracked_resolver_for_lowering,
+    } = resolver.into_outputs();
+
+    let feed = tcx.feed_unit_query();
+    feed.resolutions(tcx.arena.alloc(untracked_resolutions));
+    tcx.arena.alloc(Steal::new((untracked_resolver_for_lowering, Lrc::new(krate))))
+}
+
 fn output_filenames(tcx: TyCtxt<'_>, (): ()) -> Arc<OutputFilenames> {
     let sess = tcx.sess;
     let _timer = sess.timer("prepare_outputs");
@@ -618,6 +647,7 @@ pub static DEFAULT_QUERY_PROVIDERS: LazyLock<Providers> = LazyLock::new(|| {
     providers.analysis = analysis;
     providers.hir_crate = rustc_ast_lowering::lower_to_hir;
     providers.output_filenames = output_filenames;
+    providers.resolver_for_lowering = resolver_for_lowering;
     proc_macro_decls::provide(providers);
     rustc_const_eval::provide(providers);
     rustc_middle::hir::provide(providers);

compiler/rustc_interface/src/queries.rs

@@ -16,9 +16,8 @@ use rustc_lint::LintStore;
 use rustc_metadata::creader::CStore;
 use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::DepGraph;
-use rustc_middle::ty::{self, GlobalCtxt, TyCtxt};
+use rustc_middle::ty::{GlobalCtxt, TyCtxt};
 use rustc_query_impl::Queries as TcxQueries;
-use rustc_resolve::Resolver;
 use rustc_session::config::{self, OutputFilenames, OutputType};
 use rustc_session::cstore::Untracked;
 use rustc_session::{output::find_crate_name, Session};
@@ -216,34 +215,12 @@ impl<'tcx> Queries<'tcx> {
             qcx.enter(|tcx| {
                 let feed = tcx.feed_local_crate();
                 feed.crate_name(crate_name);
-                let (krate, resolver_outputs) = {
-                    let _timer = sess.timer("configure_and_expand");
-
-                    let arenas = Resolver::arenas();
-                    let mut resolver = Resolver::new(
-                        tcx,
-                        &krate,
-                        crate_name,
-                        self.codegen_backend().metadata_loader(),
-                        &arenas,
-                    );
-                    let krate = passes::configure_and_expand(tcx, krate, &mut resolver);
-
-                    // Make sure we don't mutate the cstore from here on.
-                    tcx.untracked().cstore.leak();
-                    (Lrc::new(krate), resolver.into_outputs())
-                };
-
-                let ty::ResolverOutputs {
-                    global_ctxt: untracked_resolutions,
-                    ast_lowering: untracked_resolver_for_lowering,
-                } = resolver_outputs;
 
                 let feed = tcx.feed_unit_query();
-                feed.resolver_for_lowering(
-                    tcx.arena.alloc(Steal::new((untracked_resolver_for_lowering, krate))),
+                feed.crate_for_resolver(tcx.arena.alloc(Steal::new(krate)));
+                feed.metadata_loader(
+                    tcx.arena.alloc(Steal::new(self.codegen_backend().metadata_loader())),
                 );
-                feed.resolutions(tcx.arena.alloc(untracked_resolutions));
                 feed.features_query(tcx.sess.features_untracked());
             });
             Ok(qcx)

compiler/rustc_middle/src/arena.rs

@@ -35,6 +35,8 @@ macro_rules! arena_types {
                 rustc_data_structures::sync::Lrc<rustc_ast::Crate>,
             )>,
             [] output_filenames: std::sync::Arc<rustc_session::config::OutputFilenames>,
+            [] metadata_loader: rustc_data_structures::steal::Steal<Box<rustc_session::cstore::MetadataLoaderDyn>>,
+            [] crate_for_resolver: rustc_data_structures::steal::Steal<rustc_ast::ast::Crate>,
             [] resolutions: rustc_middle::ty::ResolverGlobalCtxt,
             [decode] unsafety_check_result: rustc_middle::mir::UnsafetyCheckResult,
             [decode] code_region: rustc_middle::mir::coverage::CodeRegion,

compiler/rustc_middle/src/query/mod.rs

@@ -33,7 +33,7 @@ rustc_queries! {
     }
 
     query resolver_for_lowering(_: ()) -> &'tcx Steal<(ty::ResolverAstLowering, Lrc<ast::Crate>)> {
-        feedable
+        eval_always
         no_hash
         desc { "getting the resolver for lowering" }
     }
@@ -2077,6 +2077,18 @@ rustc_queries! {
         desc { "looking up enabled feature gates" }
     }
 
+    query metadata_loader((): ()) -> &'tcx Steal<Box<rustc_session::cstore::MetadataLoaderDyn>> {
+        feedable
+        no_hash
+        desc { "raw operations for metadata file access" }
+    }
+
+    query crate_for_resolver((): ()) -> &'tcx Steal<rustc_ast::ast::Crate> {
+        feedable
+        no_hash
+        desc { "the ast before macro expansion and name resolution" }
+    }
+
     /// Attempt to resolve the given `DefId` to an `Instance`, for the
     /// given generics args (`SubstsRef`), returning one of:
     ///  * `Ok(Some(instance))` on success

compiler/rustc_session/src/cstore.rs

@@ -200,7 +200,7 @@ pub enum ExternCrateSource {
 /// At the time of this writing, there is only one backend and one way to store
 /// metadata in library -- this trait just serves to decouple rustc_metadata from
 /// the archive reader, which depends on LLVM.
-pub trait MetadataLoader {
+pub trait MetadataLoader: std::fmt::Debug {
     fn get_rlib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
     fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
 }

tests/ui/panics/default-backtrace-ice.stderr

@@ -13,4 +13,5 @@ error: the compiler unexpectedly panicked. this is a bug.
 
 
 query stack during panic:
+#0 [resolver_for_lowering] getting the resolver for lowering
 end of query stack