Rollup merge of rust-lang#65625 - petrochenkov:cstore, r=Mark-Simulacrum,Zoxc

Turn crate store into a resolver output

Crate store (`CStore`) is a vector of data (`CrateMetadata`) associated with extern crates loaded during the current compilation session.

All crates are loaded in the resolver when resolving either paths pointing to extern prelude or `extern crate` items. (There are also a couple of crates like panic runtime that are loaded kind of like implicit `extern crate`s, but that also happens in resolve.)

The use of `CStore` from `rustc_plugin` (which is outside of the resolver) was unnecessary because legacy plugins are not added to the crate store and don't use `CrateNum`s.

So, `CStore` can be produced by the resolver instead of being kept in some really global data (`rustc_interface::Compiler`) like now.

As a result of crate store being more "local" we can now remove some locks and `Lrc`s.

Author: Centril

src/librustc/hir/lowering.rs

@@ -83,8 +83,6 @@ pub struct LoweringContext<'a> {
     /// Used to assign IDs to HIR nodes that do not directly correspond to AST nodes.
     sess: &'a Session,
 
-    cstore: &'a dyn CrateStore,
-
     resolver: &'a mut dyn Resolver,
 
     /// HACK(Centril): there is a cyclic dependency between the parser and lowering
@@ -160,6 +158,8 @@ pub struct LoweringContext<'a> {
 }
 
 pub trait Resolver {
+    fn cstore(&self) -> &dyn CrateStore;
+
     /// Obtains resolution for a `NodeId` with a single resolution.
     fn get_partial_res(&mut self, id: NodeId) -> Option<PartialRes>;
 
@@ -240,7 +240,6 @@ impl<'a> ImplTraitContext<'a> {
 
 pub fn lower_crate(
     sess: &Session,
-    cstore: &dyn CrateStore,
     dep_graph: &DepGraph,
     krate: &Crate,
     resolver: &mut dyn Resolver,
@@ -256,7 +255,6 @@ pub fn lower_crate(
     LoweringContext {
         crate_root: sess.parse_sess.injected_crate_name.try_get().copied(),
         sess,
-        cstore,
         resolver,
         nt_to_tokenstream,
         items: BTreeMap::new(),
@@ -980,7 +978,7 @@ impl<'a> LoweringContext<'a> {
         if id.is_local() {
             self.resolver.definitions().def_key(id.index)
         } else {
-            self.cstore.def_key(id)
+            self.resolver.cstore().def_key(id)
         }
     }
 
@@ -1727,8 +1725,8 @@ impl<'a> LoweringContext<'a> {
                             return n;
                         }
                         assert!(!def_id.is_local());
-                        let item_generics =
-                            self.cstore.item_generics_cloned_untracked(def_id, self.sess);
+                        let item_generics = self.resolver.cstore()
+                            .item_generics_cloned_untracked(def_id, self.sess);
                         let n = item_generics.own_counts().lifetimes;
                         self.type_def_lifetime_params.insert(def_id, n);
                         n

src/librustc/middle/cstore.rs

@@ -16,7 +16,7 @@ use syntax::ast;
 use syntax::symbol::Symbol;
 use syntax_pos::Span;
 use rustc_target::spec::Target;
-use rustc_data_structures::sync::{self, MetadataRef, Lrc};
+use rustc_data_structures::sync::{self, MetadataRef};
 use rustc_macros::HashStable;
 
 pub use self::NativeLibraryKind::*;
@@ -191,6 +191,8 @@ pub trait MetadataLoader {
                           -> Result<MetadataRef, String>;
 }
 
+pub type MetadataLoaderDyn = dyn MetadataLoader + Sync;
+
 /// A store of Rust crates, through which their metadata can be accessed.
 ///
 /// Note that this trait should probably not be expanding today. All new
@@ -201,13 +203,13 @@ pub trait MetadataLoader {
 /// (it'd break incremental compilation) and should only be called pre-HIR (e.g.
 /// during resolve)
 pub trait CrateStore {
-    fn crate_data_as_rc_any(&self, krate: CrateNum) -> Lrc<dyn Any>;
+    fn crate_data_as_any(&self, cnum: CrateNum) -> &dyn Any;
 
     // resolve
     fn def_key(&self, def: DefId) -> DefKey;
     fn def_path(&self, def: DefId) -> hir_map::DefPath;
     fn def_path_hash(&self, def: DefId) -> hir_map::DefPathHash;
-    fn def_path_table(&self, cnum: CrateNum) -> Lrc<DefPathTable>;
+    fn def_path_table(&self, cnum: CrateNum) -> &DefPathTable;
 
     // "queries" used in resolve that aren't tracked for incremental compilation
     fn crate_name_untracked(&self, cnum: CrateNum) -> Symbol;

src/librustc/ty/context.rs

@@ -1027,7 +1027,7 @@ pub struct GlobalCtxt<'tcx> {
 
     interners: CtxtInterners<'tcx>,
 
-    cstore: &'tcx CrateStoreDyn,
+    cstore: Box<CrateStoreDyn>,
 
     pub sess: &'tcx Session,
 
@@ -1195,11 +1195,10 @@ impl<'tcx> TyCtxt<'tcx> {
     pub fn create_global_ctxt(
         s: &'tcx Session,
         lint_store: Lrc<lint::LintStore>,
-        cstore: &'tcx CrateStoreDyn,
         local_providers: ty::query::Providers<'tcx>,
         extern_providers: ty::query::Providers<'tcx>,
         arenas: &'tcx AllArenas,
-        resolutions: ty::Resolutions,
+        resolutions: ty::ResolverOutputs,
         hir: hir_map::Map<'tcx>,
         on_disk_query_result_cache: query::OnDiskCache<'tcx>,
         crate_name: &str,
@@ -1213,34 +1212,28 @@ impl<'tcx> TyCtxt<'tcx> {
         let common_lifetimes = CommonLifetimes::new(&interners);
         let common_consts = CommonConsts::new(&interners, &common_types);
         let dep_graph = hir.dep_graph.clone();
-        let max_cnum = cstore.crates_untracked().iter().map(|c| c.as_usize()).max().unwrap_or(0);
+        let cstore = resolutions.cstore;
+        let crates = cstore.crates_untracked();
+        let max_cnum = crates.iter().map(|c| c.as_usize()).max().unwrap_or(0);
         let mut providers = IndexVec::from_elem_n(extern_providers, max_cnum + 1);
         providers[LOCAL_CRATE] = local_providers;
 
         let def_path_hash_to_def_id = if s.opts.build_dep_graph() {
-            let upstream_def_path_tables: Vec<(CrateNum, Lrc<_>)> = cstore
-                .crates_untracked()
+            let def_path_tables = crates
                 .iter()
                 .map(|&cnum| (cnum, cstore.def_path_table(cnum)))
-                .collect();
-
-            let def_path_tables = || {
-                upstream_def_path_tables
-                    .iter()
-                    .map(|&(cnum, ref rc)| (cnum, &**rc))
-                    .chain(iter::once((LOCAL_CRATE, hir.definitions().def_path_table())))
-            };
+                .chain(iter::once((LOCAL_CRATE, hir.definitions().def_path_table())));
 
             // Precompute the capacity of the hashmap so we don't have to
             // re-allocate when populating it.
-            let capacity = def_path_tables().map(|(_, t)| t.size()).sum::<usize>();
+            let capacity = def_path_tables.clone().map(|(_, t)| t.size()).sum::<usize>();
 
             let mut map: FxHashMap<_, _> = FxHashMap::with_capacity_and_hasher(
                 capacity,
                 ::std::default::Default::default()
             );
 
-            for (cnum, def_path_table) in def_path_tables() {
+            for (cnum, def_path_table) in def_path_tables {
                 def_path_table.add_def_path_hashes_to(cnum, &mut map);
             }
 
@@ -1417,8 +1410,8 @@ impl<'tcx> TyCtxt<'tcx> {
 
     // Note that this is *untracked* and should only be used within the query
     // system if the result is otherwise tracked through queries
-    pub fn crate_data_as_rc_any(self, cnum: CrateNum) -> Lrc<dyn Any> {
-        self.cstore.crate_data_as_rc_any(cnum)
+    pub fn crate_data_as_any(self, cnum: CrateNum) -> &'tcx dyn Any {
+        self.cstore.crate_data_as_any(cnum)
     }
 
     #[inline(always)]
@@ -1428,7 +1421,7 @@ impl<'tcx> TyCtxt<'tcx> {
         StableHashingContext::new(self.sess,
                                   krate,
                                   self.hir().definitions(),
-                                  self.cstore)
+                                  &*self.cstore)
     }
 
     // This method makes sure that we have a DepNode and a Fingerprint for

src/librustc/ty/mod.rs

@@ -15,6 +15,7 @@ use rustc_macros::HashStable;
 use crate::ich::Fingerprint;
 use crate::ich::StableHashingContext;
 use crate::infer::canonical::Canonical;
+use crate::middle::cstore::CrateStoreDyn;
 use crate::middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangItem};
 use crate::middle::resolve_lifetime::ObjectLifetimeDefault;
 use crate::mir::Body;
@@ -119,8 +120,9 @@ mod sty;
 
 // Data types
 
-#[derive(Clone)]
-pub struct Resolutions {
+pub struct ResolverOutputs {
+    pub definitions: hir_map::Definitions,
+    pub cstore: Box<CrateStoreDyn>,
     pub extern_crate_map: NodeMap<CrateNum>,
     pub trait_map: TraitMap,
     pub maybe_unused_trait_imports: NodeSet,

src/librustc_codegen_llvm/lib.rs

@@ -56,7 +56,7 @@ use std::sync::Arc;
 use std::ffi::CStr;
 
 use rustc::dep_graph::DepGraph;
-use rustc::middle::cstore::{EncodedMetadata, MetadataLoader};
+use rustc::middle::cstore::{EncodedMetadata, MetadataLoaderDyn};
 use rustc::session::Session;
 use rustc::session::config::{OutputFilenames, OutputType, PrintRequest, OptLevel};
 use rustc::ty::{self, TyCtxt};
@@ -260,7 +260,7 @@ impl CodegenBackend for LlvmCodegenBackend {
         target_features(sess)
     }
 
-    fn metadata_loader(&self) -> Box<dyn MetadataLoader + Sync> {
+    fn metadata_loader(&self) -> Box<MetadataLoaderDyn> {
         box metadata::LlvmMetadataLoader
     }
 

src/librustc_codegen_utils/codegen_backend.rs

@@ -14,7 +14,7 @@ use rustc::util::common::ErrorReported;
 use rustc::session::config::{OutputFilenames, PrintRequest};
 use rustc::ty::TyCtxt;
 use rustc::ty::query::Providers;
-use rustc::middle::cstore::{EncodedMetadata, MetadataLoader};
+use rustc::middle::cstore::{EncodedMetadata, MetadataLoaderDyn};
 use rustc::dep_graph::DepGraph;
 
 pub use rustc_data_structures::sync::MetadataRef;
@@ -26,7 +26,7 @@ pub trait CodegenBackend {
     fn print_passes(&self) {}
     fn print_version(&self) {}
 
-    fn metadata_loader(&self) -> Box<dyn MetadataLoader + Sync>;
+    fn metadata_loader(&self) -> Box<MetadataLoaderDyn>;
     fn provide(&self, _providers: &mut Providers<'_>);
     fn provide_extern(&self, _providers: &mut Providers<'_>);
     fn codegen_crate<'tcx>(

src/librustc_driver/lib.rs

@@ -36,11 +36,11 @@ use rustc::session::config::nightly_options;
 use rustc::session::{early_error, early_warn};
 use rustc::lint::Lint;
 use rustc::lint;
+use rustc::middle::cstore::MetadataLoader;
 use rustc::hir::def_id::LOCAL_CRATE;
 use rustc::ty::TyCtxt;
 use rustc::util::common::{set_time_depth, time, print_time_passes_entry, ErrorReported};
 use rustc_metadata::locator;
-use rustc_metadata::cstore::CStore;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_interface::interface;
 use rustc_interface::util::get_codegen_sysroot;
@@ -277,7 +277,7 @@ pub fn run_compiler(
             compiler.output_file(),
         ).and_then(|| RustcDefaultCalls::list_metadata(
             sess,
-            compiler.cstore(),
+            &*compiler.codegen_backend().metadata_loader(),
             &matches,
             compiler.input()
         ));
@@ -614,7 +614,7 @@ fn show_content_with_pager(content: &String) {
 
 impl RustcDefaultCalls {
     pub fn list_metadata(sess: &Session,
-                         cstore: &CStore,
+                         metadata_loader: &dyn MetadataLoader,
                          matches: &getopts::Matches,
                          input: &Input)
                          -> Compilation {
@@ -626,7 +626,7 @@ impl RustcDefaultCalls {
                     let mut v = Vec::new();
                     locator::list_file_metadata(&sess.target.target,
                                                 path,
-                                                cstore,
+                                                metadata_loader,
                                                 &mut v)
                             .unwrap();
                     println!("{}", String::from_utf8(v).unwrap());

src/librustc_interface/interface.rs

@@ -11,7 +11,6 @@ use rustc_codegen_utils::codegen_backend::CodegenBackend;
 use rustc_data_structures::OnDrop;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::fx::{FxHashSet, FxHashMap};
-use rustc_metadata::cstore::CStore;
 use std::path::PathBuf;
 use std::result;
 use std::sync::{Arc, Mutex};
@@ -37,7 +36,6 @@ pub struct Compiler {
     pub(crate) output_dir: Option<PathBuf>,
     pub(crate) output_file: Option<PathBuf>,
     pub(crate) queries: Queries,
-    pub(crate) cstore: Lrc<CStore>,
     pub(crate) crate_name: Option<String>,
     pub(crate) register_lints: Option<Box<dyn Fn(&Session, &mut lint::LintStore) + Send + Sync>>,
 }
@@ -49,9 +47,6 @@ impl Compiler {
     pub fn codegen_backend(&self) -> &Lrc<Box<dyn CodegenBackend>> {
         &self.codegen_backend
     }
-    pub fn cstore(&self) -> &Lrc<CStore> {
-        &self.cstore
-    }
     pub fn source_map(&self) -> &Lrc<SourceMap> {
         &self.source_map
     }
@@ -160,13 +155,10 @@ where
         config.lint_caps,
     );
 
-    let cstore = Lrc::new(CStore::new(codegen_backend.metadata_loader()));
-
     let compiler = Compiler {
         sess,
         codegen_backend,
         source_map,
-        cstore,
         input: config.input,
         input_path: config.input_path,
         output_dir: config.output_dir,