Auto merge of #66697 - petrochenkov:nocstore, r=eddyb

rustc_metadata: Privatize more things and a couple of other refactorings

This PR continues #66496 and hits the point of diminishing returns.
All fields of `CrateRoot` and `CrateMetadata` are privatized.
For read-only fields this certainly makes sense, but for a few fields updateable from outside of `rmeta.rs` (mostly `creader.rs`) it was done mostly for consistency, I can make them `pub(crate)` again if requested.

`cstore.rs` (which became small after #66496) was merged into `creader.rs`.

A few things noticed while making the privacy changes were addressed in the remaining refactoring commits.

Fixes #66550
r? @eddyb @Mark-Simulacrum

Author: bors

Diff for: src/librustc/middle/cstore.rs

@@ -146,6 +146,13 @@ impl ExternCrate {
     pub fn is_direct(&self) -> bool {
         self.dependency_of == LOCAL_CRATE
     }
+
+    pub fn rank(&self) -> impl PartialOrd {
+        // Prefer:
+        // - direct extern crate to indirect
+        // - shorter paths to longer
+        (self.is_direct(), !self.path_len)
+    }
 }
 
 #[derive(Copy, Clone, Debug, HashStable)]
@@ -204,7 +211,7 @@ pub type MetadataLoaderDyn = dyn MetadataLoader + Sync;
 /// (it'd break incremental compilation) and should only be called pre-HIR (e.g.
 /// during resolve)
 pub trait CrateStore {
-    fn crate_data_as_any(&self, cnum: CrateNum) -> &dyn Any;
+    fn as_any(&self) -> &dyn Any;
 
     // resolve
     fn def_key(&self, def: DefId) -> DefKey;
@@ -217,9 +224,7 @@ pub trait CrateStore {
     fn crate_is_private_dep_untracked(&self, cnum: CrateNum) -> bool;
     fn crate_disambiguator_untracked(&self, cnum: CrateNum) -> CrateDisambiguator;
     fn crate_hash_untracked(&self, cnum: CrateNum) -> Svh;
-    fn crate_host_hash_untracked(&self, cnum: CrateNum) -> Option<Svh>;
     fn item_generics_cloned_untracked(&self, def: DefId, sess: &Session) -> ty::Generics;
-    fn postorder_cnums_untracked(&self) -> Vec<CrateNum>;
 
     // This is basically a 1-based range of ints, which is a little
     // silly - I may fix that.
@@ -228,7 +233,6 @@ pub trait CrateStore {
     // utility functions
     fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata;
     fn metadata_encoding_version(&self) -> &[u8];
-    fn injected_panic_runtime(&self) -> Option<CrateNum>;
     fn allocator_kind(&self) -> Option<AllocatorKind>;
 }
 

Diff for: src/librustc/session/mod.rs

@@ -133,9 +133,6 @@ pub struct Session {
     /// false positives about a job server in our environment.
     pub jobserver: Client,
 
-    /// Metadata about the allocators for the current crate being compiled.
-    pub has_global_allocator: Once<bool>,
-
     /// Cap lint level specified by a driver specifically.
     pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
 
@@ -1180,7 +1177,6 @@ fn build_session_(
         print_fuel_crate,
         print_fuel,
         jobserver: jobserver::client(),
-        has_global_allocator: Once::new(),
         driver_lint_caps,
         trait_methods_not_found: Lock::new(Default::default()),
         confused_type_with_std_module: Lock::new(Default::default()),

Diff for: src/librustc/ty/context.rs

@@ -1307,10 +1307,6 @@ impl<'tcx> TyCtxt<'tcx> {
         self.all_crate_nums(LOCAL_CRATE)
     }
 
-    pub fn injected_panic_runtime(self) -> Option<CrateNum> {
-        self.cstore.injected_panic_runtime()
-    }
-
     pub fn allocator_kind(self) -> Option<AllocatorKind> {
         self.cstore.allocator_kind()
     }
@@ -1391,8 +1387,8 @@ 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_any(self, cnum: CrateNum) -> &'tcx dyn Any {
-        self.cstore.crate_data_as_any(cnum)
+    pub fn cstore_as_any(self) -> &'tcx dyn Any {
+        self.cstore.as_any()
     }
 
     #[inline(always)]
@@ -2999,14 +2995,6 @@ pub fn provide(providers: &mut ty::query::Providers<'_>) {
         assert_eq!(cnum, LOCAL_CRATE);
         tcx.arena.alloc_slice(&tcx.cstore.crates_untracked())
     };
-    providers.crate_host_hash = |tcx, cnum| {
-        assert_ne!(cnum, LOCAL_CRATE);
-        tcx.cstore.crate_host_hash_untracked(cnum)
-    };
-    providers.postorder_cnums = |tcx, cnum| {
-        assert_eq!(cnum, LOCAL_CRATE);
-        tcx.arena.alloc_slice(&tcx.cstore.postorder_cnums_untracked())
-    };
     providers.output_filenames = |tcx, cnum| {
         assert_eq!(cnum, LOCAL_CRATE);
         tcx.output_filenames.clone()

Diff for: src/librustc_interface/passes.rs

@@ -25,7 +25,6 @@ use rustc_data_structures::{box_region_allow_access, declare_box_region_type, pa
 use rustc_data_structures::sync::{Lrc, ParallelIterator, par_iter};
 use rustc_errors::PResult;
 use rustc_incremental;
-use rustc_metadata::cstore;
 use rustc_mir as mir;
 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str};
 use rustc_passes::{self, ast_validation, hir_stats, layout_test};
@@ -728,15 +727,15 @@ pub fn default_provide(providers: &mut ty::query::Providers<'_>) {
     rustc_passes::provide(providers);
     rustc_traits::provide(providers);
     middle::region::provide(providers);
-    cstore::provide(providers);
+    rustc_metadata::provide(providers);
     lint::provide(providers);
     rustc_lint::provide(providers);
     rustc_codegen_utils::provide(providers);
     rustc_codegen_ssa::provide(providers);
 }
 
 pub fn default_provide_extern(providers: &mut ty::query::Providers<'_>) {
-    cstore::provide_extern(providers);
+    rustc_metadata::provide_extern(providers);
     rustc_codegen_ssa::provide_extern(providers);
 }