Remove QueryEngine trait

Author: Zoxc

Cargo.lock

@@ -3641,6 +3641,7 @@ dependencies = [
  "rustc_plugin_impl",
  "rustc_privacy",
  "rustc_query_impl",
+ "rustc_query_system",
  "rustc_resolve",
  "rustc_session",
  "rustc_span",
@@ -3770,6 +3771,7 @@ dependencies = [
  "derive_more",
  "either",
  "gsgdt",
+ "measureme",
  "polonius-engine",
  "rustc-rayon",
  "rustc-rayon-core",

compiler/rustc_incremental/src/persist/load.rs

@@ -4,7 +4,7 @@ use crate::errors;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::memmap::Mmap;
 use rustc_middle::dep_graph::{SerializedDepGraph, WorkProduct, WorkProductId};
-use rustc_middle::ty::OnDiskCache;
+use rustc_middle::query::on_disk_cache::OnDiskCache;
 use rustc_serialize::opaque::MemDecoder;
 use rustc_serialize::Decodable;
 use rustc_session::config::IncrementalStateAssertion;
@@ -211,7 +211,7 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture {
 /// If we are not in incremental compilation mode, returns `None`.
 /// Otherwise, tries to load the query result cache from disk,
 /// creating an empty cache if it could not be loaded.
-pub fn load_query_result_cache<'a, C: OnDiskCache<'a>>(sess: &'a Session) -> Option<C> {
+pub fn load_query_result_cache(sess: &Session) -> Option<OnDiskCache<'_>> {
     if sess.opts.incremental.is_none() {
         return None;
     }
@@ -223,7 +223,9 @@ pub fn load_query_result_cache<'a, C: OnDiskCache<'a>>(sess: &'a Session) -> Opt
         &query_cache_path(sess),
         sess.is_nightly_build(),
     ) {
-        LoadResult::Ok { data: (bytes, start_pos) } => Some(C::new(sess, bytes, start_pos)),
-        _ => Some(C::new_empty(sess.source_map())),
+        LoadResult::Ok { data: (bytes, start_pos) } => {
+            Some(OnDiskCache::new(sess, bytes, start_pos))
+        }
+        _ => Some(OnDiskCache::new_empty(sess.source_map())),
     }
 }

compiler/rustc_incremental/src/persist/save.rs

@@ -48,7 +48,7 @@ pub fn save_dep_graph(tcx: TyCtxt<'_>) {
             move || {
                 sess.time("incr_comp_persist_result_cache", || {
                     // Drop the memory map so that we can remove the file and write to it.
-                    if let Some(odc) = &tcx.on_disk_cache {
+                    if let Some(odc) = &tcx.query_system.on_disk_cache {
                         odc.drop_serialized_data(tcx);
                     }
 

compiler/rustc_interface/Cargo.toml

@@ -44,6 +44,7 @@ rustc_lint = { path = "../rustc_lint" }
 rustc_errors = { path = "../rustc_errors" }
 rustc_plugin_impl = { path = "../rustc_plugin_impl" }
 rustc_privacy = { path = "../rustc_privacy" }
+rustc_query_system = { path = "../rustc_query_system" }
 rustc_query_impl = { path = "../rustc_query_impl" }
 rustc_resolve = { path = "../rustc_resolve" }
 rustc_target = { path = "../rustc_target" }

compiler/rustc_interface/src/interface.rs

@@ -12,6 +12,7 @@ use rustc_lint::LintStore;
 use rustc_middle::ty;
 use rustc_parse::maybe_new_parser_from_source_str;
 use rustc_query_impl::QueryCtxt;
+use rustc_query_system::query::print_query_stack;
 use rustc_session::config::{self, CheckCfg, ErrorOutputType, Input, OutputFilenames};
 use rustc_session::lint;
 use rustc_session::parse::{CrateConfig, ParseSess};
@@ -317,7 +318,7 @@ pub fn try_print_query_stack(handler: &Handler, num_frames: Option<usize>) {
     // state if it was responsible for triggering the panic.
     let i = ty::tls::with_context_opt(|icx| {
         if let Some(icx) = icx {
-            QueryCtxt::from_tcx(icx.tcx).try_print_query_stack(icx.query, handler, num_frames)
+            print_query_stack(QueryCtxt { tcx: icx.tcx }, icx.query, handler, num_frames)
         } else {
             0
         }

compiler/rustc_interface/src/passes.rs

@@ -23,7 +23,6 @@ use rustc_mir_build as mir_build;
 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str, validate_attr};
 use rustc_passes::{self, hir_stats, layout_test};
 use rustc_plugin_impl as plugin;
-use rustc_query_impl::{OnDiskCache, Queries as TcxQueries};
 use rustc_resolve::Resolver;
 use rustc_session::config::{CrateType, Input, OutputFilenames, OutputType};
 use rustc_session::cstore::{MetadataLoader, Untracked};
@@ -669,7 +668,6 @@ pub fn create_global_ctxt<'tcx>(
     lint_store: Lrc<LintStore>,
     dep_graph: DepGraph,
     untracked: Untracked,
-    queries: &'tcx OnceCell<TcxQueries<'tcx>>,
     gcx_cell: &'tcx OnceCell<GlobalCtxt<'tcx>>,
     arena: &'tcx WorkerLocal<Arena<'tcx>>,
     hir_arena: &'tcx WorkerLocal<rustc_hir::Arena<'tcx>>,
@@ -693,10 +691,6 @@ pub fn create_global_ctxt<'tcx>(
         callback(sess, &mut local_providers, &mut extern_providers);
     }
 
-    let queries = queries.get_or_init(|| {
-        TcxQueries::new(local_providers, extern_providers, query_result_on_disk_cache)
-    });
-
     sess.time("setup_global_ctxt", || {
         gcx_cell.get_or_init(move || {
             TyCtxt::create_global_ctxt(
@@ -706,9 +700,9 @@ pub fn create_global_ctxt<'tcx>(
                 hir_arena,
                 untracked,
                 dep_graph,
-                queries.on_disk_cache.as_ref().map(OnDiskCache::as_dyn),
-                queries.as_dyn(),
+                query_result_on_disk_cache,
                 rustc_query_impl::query_callbacks(arena),
+                rustc_query_impl::query_system_fns(local_providers, extern_providers),
             )
         })
     })

compiler/rustc_interface/src/queries.rs

@@ -16,7 +16,6 @@ use rustc_metadata::creader::CStore;
 use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::DepGraph;
 use rustc_middle::ty::{GlobalCtxt, TyCtxt};
-use rustc_query_impl::Queries as TcxQueries;
 use rustc_session::config::{self, OutputFilenames, OutputType};
 use rustc_session::cstore::Untracked;
 use rustc_session::{output::find_crate_name, Session};
@@ -81,7 +80,6 @@ impl<T> Default for Query<T> {
 pub struct Queries<'tcx> {
     compiler: &'tcx Compiler,
     gcx_cell: OnceCell<GlobalCtxt<'tcx>>,
-    queries: OnceCell<TcxQueries<'tcx>>,
 
     arena: WorkerLocal<Arena<'tcx>>,
     hir_arena: WorkerLocal<rustc_hir::Arena<'tcx>>,
@@ -102,7 +100,6 @@ impl<'tcx> Queries<'tcx> {
         Queries {
             compiler,
             gcx_cell: OnceCell::new(),
-            queries: OnceCell::new(),
             arena: WorkerLocal::new(|_| Arena::default()),
             hir_arena: WorkerLocal::new(|_| rustc_hir::Arena::default()),
             dep_graph_future: Default::default(),
@@ -225,7 +222,6 @@ impl<'tcx> Queries<'tcx> {
                 lint_store,
                 self.dep_graph()?.steal(),
                 untracked,
-                &self.queries,
                 &self.gcx_cell,
                 &self.arena,
                 &self.hir_arena,

compiler/rustc_interface/src/util.rs

@@ -168,7 +168,8 @@ pub(crate) fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
 ) -> R {
     use rustc_data_structures::jobserver;
     use rustc_middle::ty::tls;
-    use rustc_query_impl::{deadlock, QueryContext, QueryCtxt};
+    use rustc_query_impl::QueryCtxt;
+    use rustc_query_system::query::{deadlock, QueryContext};
 
     let mut builder = rayon::ThreadPoolBuilder::new()
         .thread_name(|_| "rustc".to_string())
@@ -179,7 +180,7 @@ pub(crate) fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
             // On deadlock, creates a new thread and forwards information in thread
             // locals to it. The new thread runs the deadlock handler.
             let query_map = tls::with(|tcx| {
-                QueryCtxt::from_tcx(tcx)
+                QueryCtxt::new(tcx)
                     .try_collect_active_jobs()
                     .expect("active jobs shouldn't be locked in deadlock handler")
             });

compiler/rustc_middle/Cargo.toml

@@ -11,6 +11,7 @@ chalk-ir = "0.87.0"
 derive_more = "0.99.17"
 either = "1.5.0"
 gsgdt = "0.1.2"
+measureme = "10.0.0"
 polonius-engine = "0.13.0"
 rustc_apfloat = { path = "../rustc_apfloat" }
 rustc_arena = { path = "../rustc_arena" }

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -227,7 +227,9 @@ pub fn specialized_encode_alloc_id<'tcx, E: TyEncoder<I = TyCtxt<'tcx>>>(
             // References to statics doesn't need to know about their allocations,
             // just about its `DefId`.
             AllocDiscriminant::Static.encode(encoder);
-            did.encode(encoder);
+            // Cannot use `did.encode(encoder)` because of a bug around
+            // specializations and method calls.
+            Encodable::<E>::encode(&did, encoder);
         }
     }
 }

compiler/rustc_middle/src/query/mod.rs

@@ -9,6 +9,7 @@ use rustc_span::def_id::LOCAL_CRATE;
 
 pub mod erase;
 mod keys;
+pub mod on_disk_cache;
 pub use keys::{AsLocalKey, Key, LocalCrate};
 
 // Each of these queries corresponds to a function pointer field in the

compiler/rustc_middle/src/query/on_disk_cache.rs

@@ -1,4 +1,3 @@
-use crate::QueryCtxt;
 use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::stable_hasher::Hash64;
@@ -13,8 +12,7 @@ use rustc_middle::mir::interpret::{AllocDecodingSession, AllocDecodingState};
 use rustc_middle::mir::{self, interpret};
 use rustc_middle::ty::codec::{RefDecodable, TyDecoder, TyEncoder};
 use rustc_middle::ty::{self, Ty, TyCtxt};
-use rustc_query_system::dep_graph::DepContext;
-use rustc_query_system::query::{QueryCache, QuerySideEffects};
+use rustc_query_system::query::QuerySideEffects;
 use rustc_serialize::{
     opaque::{FileEncodeResult, FileEncoder, IntEncodedWithFixedSize, MemDecoder},
     Decodable, Decoder, Encodable, Encoder,
@@ -123,7 +121,7 @@ struct SourceFileIndex(u32);
 pub struct AbsoluteBytePos(u64);
 
 impl AbsoluteBytePos {
-    fn new(pos: usize) -> AbsoluteBytePos {
+    pub fn new(pos: usize) -> AbsoluteBytePos {
         AbsoluteBytePos(pos.try_into().expect("Incremental cache file size overflowed u64."))
     }
 
@@ -158,9 +156,9 @@ impl EncodedSourceFileId {
     }
 }
 
-impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
+impl<'sess> OnDiskCache<'sess> {
     /// Creates a new `OnDiskCache` instance from the serialized data in `data`.
-    fn new(sess: &'sess Session, data: Mmap, start_pos: usize) -> Self {
+    pub fn new(sess: &'sess Session, data: Mmap, start_pos: usize) -> Self {
         debug_assert!(sess.opts.incremental.is_some());
 
         // Wrap in a scope so we can borrow `data`.
@@ -193,7 +191,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
         }
     }
 
-    fn new_empty(source_map: &'sess SourceMap) -> Self {
+    pub fn new_empty(source_map: &'sess SourceMap) -> Self {
         Self {
             serialized_data: RwLock::new(None),
             file_index_to_stable_id: Default::default(),
@@ -215,7 +213,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
     /// Cache promotions require invoking queries, which needs to read the serialized data.
     /// In order to serialize the new on-disk cache, the former on-disk cache file needs to be
     /// deleted, hence we won't be able to refer to its memmapped data.
-    fn drop_serialized_data(&self, tcx: TyCtxt<'_>) {
+    pub fn drop_serialized_data(&self, tcx: TyCtxt<'_>) {
         // Load everything into memory so we can write it out to the on-disk
         // cache. The vast majority of cacheable query results should already
         // be in memory, so this should be a cheap operation.
@@ -227,7 +225,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
         *self.serialized_data.write() = None;
     }
 
-    fn serialize(&self, tcx: TyCtxt<'_>, encoder: FileEncoder) -> FileEncodeResult {
+    pub fn serialize(&self, tcx: TyCtxt<'_>, encoder: FileEncoder) -> FileEncodeResult {
         // Serializing the `DepGraph` should not modify it.
         tcx.dep_graph.with_ignore(|| {
             // Allocate `SourceFileIndex`es.
@@ -269,7 +267,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
             tcx.sess.time("encode_query_results", || {
                 let enc = &mut encoder;
                 let qri = &mut query_result_index;
-                QueryCtxt::from_tcx(tcx).encode_query_results(enc, qri);
+                (tcx.query_system.fns.encode_query_results)(tcx, enc, qri);
             });
 
             // Encode side effects.
@@ -358,12 +356,6 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
             encoder.finish()
         })
     }
-}
-
-impl<'sess> OnDiskCache<'sess> {
-    pub fn as_dyn(&self) -> &dyn rustc_middle::ty::OnDiskCache<'sess> {
-        self as _
-    }
 
     /// Loads a `QuerySideEffects` created during the previous compilation session.
     pub fn load_side_effects(
@@ -855,7 +847,7 @@ impl<'a, 'tcx> CacheEncoder<'a, 'tcx> {
     /// encode the specified tag, then the given value, then the number of
     /// bytes taken up by tag and value. On decoding, we can then verify that
     /// we get the expected tag and read the expected number of bytes.
-    fn encode_tagged<T: Encodable<Self>, V: Encodable<Self>>(&mut self, tag: T, value: &V) {
+    pub fn encode_tagged<T: Encodable<Self>, V: Encodable<Self>>(&mut self, tag: T, value: &V) {
         let start_pos = self.position();
 
         tag.encode(self);
@@ -1032,33 +1024,3 @@ impl<'a, 'tcx> Encodable<CacheEncoder<'a, 'tcx>> for [u8] {
         self.encode(&mut e.encoder);
     }
 }
-
-pub(crate) fn encode_query_results<'a, 'tcx, Q>(
-    query: Q,
-    qcx: QueryCtxt<'tcx>,
-    encoder: &mut CacheEncoder<'a, 'tcx>,
-    query_result_index: &mut EncodedDepNodeIndex,
-) where
-    Q: super::QueryConfigRestored<'tcx>,
-    Q::RestoredValue: Encodable<CacheEncoder<'a, 'tcx>>,
-{
-    let _timer = qcx
-        .tcx
-        .profiler()
-        .verbose_generic_activity_with_arg("encode_query_results_for", query.name());
-
-    assert!(query.query_state(qcx).all_inactive());
-    let cache = query.query_cache(qcx);
-    cache.iter(&mut |key, value, dep_node| {
-        if query.cache_on_disk(qcx.tcx, &key) {
-            let dep_node = SerializedDepNodeIndex::new(dep_node.index());
-
-            // Record position of the cache entry.
-            query_result_index.push((dep_node, AbsoluteBytePos::new(encoder.encoder.position())));
-
-            // Encode the type check tables with the `SerializedDepNodeIndex`
-            // as tag.
-            encoder.encode_tagged(dep_node, &Q::restore(*value));
-        }
-    });
-}

compiler/rustc_middle/src/ty/codec.rs

@@ -500,7 +500,6 @@ impl_arena_copy_decoder! {<'tcx>
 macro_rules! implement_ty_decoder {
     ($DecoderName:ident <$($typaram:tt),*>) => {
         mod __ty_decoder_impl {
-            use std::borrow::Cow;
             use rustc_serialize::Decoder;
 
             use super::$DecoderName;

compiler/rustc_middle/src/ty/context.rs

@@ -14,11 +14,14 @@ use crate::middle::resolve_bound_vars;
 use crate::middle::stability;
 use crate::mir::interpret::{self, Allocation, ConstAllocation};
 use crate::mir::{Body, Local, Place, PlaceElem, ProjectionKind, Promoted};
+use crate::query::on_disk_cache::OnDiskCache;
 use crate::query::LocalCrate;
 use crate::thir::Thir;
 use crate::traits;
 use crate::traits::solve;
 use crate::traits::solve::{ExternalConstraints, ExternalConstraintsData};
+use crate::ty::query::QuerySystem;
+use crate::ty::query::QuerySystemFns;
 use crate::ty::query::{self, TyCtxtAt};
 use crate::ty::{
     self, AdtDef, AdtDefData, AdtKind, Binder, Const, ConstData, FloatTy, FloatVar, FloatVid,
@@ -31,7 +34,6 @@ use rustc_ast::{self as ast, attr};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::intern::Interned;
-use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::profiling::SelfProfilerRef;
 use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
@@ -61,7 +63,6 @@ use rustc_session::lint::Lint;
 use rustc_session::Limit;
 use rustc_session::Session;
 use rustc_span::def_id::{DefPathHash, StableCrateId};
-use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 use rustc_target::abi::{FieldIdx, Layout, LayoutS, TargetDataLayout, VariantIdx};
@@ -84,21 +85,6 @@ use super::query::IntoQueryParam;
 
 const TINY_CONST_EVAL_LIMIT: Limit = Limit(20);
 
-pub trait OnDiskCache<'tcx>: rustc_data_structures::sync::Sync {
-    /// Creates a new `OnDiskCache` instance from the serialized data in `data`.
-    fn new(sess: &'tcx Session, data: Mmap, start_pos: usize) -> Self
-    where
-        Self: Sized;
-
-    fn new_empty(source_map: &'tcx SourceMap) -> Self
-    where
-        Self: Sized;
-
-    fn drop_serialized_data(&self, tcx: TyCtxt<'tcx>);
-
-    fn serialize(&self, tcx: TyCtxt<'tcx>, encoder: FileEncoder) -> FileEncodeResult;
-}
-
 #[allow(rustc::usage_of_ty_tykind)]
 impl<'tcx> Interner for TyCtxt<'tcx> {
     type AdtDef = ty::AdtDef<'tcx>;
@@ -527,13 +513,6 @@ pub struct GlobalCtxt<'tcx> {
 
     untracked: Untracked,
 
-    /// This provides access to the incremental compilation on-disk cache for query results.
-    /// Do not access this directly. It is only meant to be used by
-    /// `DepGraph::try_mark_green()` and the query infrastructure.
-    /// This is `None` if we are not incremental compilation mode
-    pub on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
-
-    pub queries: &'tcx dyn query::QueryEngine<'tcx>,
     pub query_system: query::QuerySystem<'tcx>,
     pub(crate) query_kinds: &'tcx [DepKindStruct<'tcx>],
 
@@ -674,9 +653,9 @@ impl<'tcx> TyCtxt<'tcx> {
         hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
         untracked: Untracked,
         dep_graph: DepGraph,
-        on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
-        queries: &'tcx dyn query::QueryEngine<'tcx>,
+        on_disk_cache: Option<OnDiskCache<'tcx>>,
         query_kinds: &'tcx [DepKindStruct<'tcx>],
+        query_system_fns: QuerySystemFns<'tcx>,
     ) -> GlobalCtxt<'tcx> {
         let data_layout = s.target.parse_data_layout().unwrap_or_else(|err| {
             s.emit_fatal(err);
@@ -698,9 +677,7 @@ impl<'tcx> TyCtxt<'tcx> {
             lifetimes: common_lifetimes,
             consts: common_consts,
             untracked,
-            on_disk_cache,
-            queries,
-            query_system: Default::default(),
+            query_system: QuerySystem::new(query_system_fns, on_disk_cache),
             query_kinds,
             ty_rcache: Default::default(),
             pred_rcache: Default::default(),
@@ -1039,7 +1016,7 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     pub fn serialize_query_result_cache(self, encoder: FileEncoder) -> FileEncodeResult {
-        self.on_disk_cache.as_ref().map_or(Ok(0), |c| c.serialize(self, encoder))
+        self.query_system.on_disk_cache.as_ref().map_or(Ok(0), |c| c.serialize(self, encoder))
     }
 
     /// If `true`, we should use lazy normalization for constants, otherwise

compiler/rustc_middle/src/ty/mod.rs

@@ -84,8 +84,7 @@ pub use self::consts::{
     Const, ConstData, ConstInt, ConstKind, Expr, InferConst, ScalarInt, UnevaluatedConst, ValTree,
 };
 pub use self::context::{
-    tls, CtxtInterners, DeducedParamAttrs, FreeRegionInfo, GlobalCtxt, Lift, OnDiskCache, TyCtxt,
-    TyCtxtFeed,
+    tls, CtxtInterners, DeducedParamAttrs, FreeRegionInfo, GlobalCtxt, Lift, TyCtxt, TyCtxtFeed,
 };
 pub use self::instance::{Instance, InstanceDef, ShortInstance, UnusedGenericParams};
 pub use self::list::List;

compiler/rustc_middle/src/ty/query.rs

@@ -1,6 +1,7 @@
 #![allow(unused_parens)]
 
 use crate::dep_graph;
+use crate::dep_graph::DepKind;
 use crate::infer::canonical::{self, Canonical};
 use crate::lint::LintExpectation;
 use crate::metadata::ModChild;
@@ -17,7 +18,11 @@ use crate::mir::interpret::{
 };
 use crate::mir::interpret::{LitToConstError, LitToConstInput};
 use crate::mir::mono::CodegenUnit;
+
 use crate::query::erase::{erase, restore, Erase};
+use crate::query::on_disk_cache::CacheEncoder;
+use crate::query::on_disk_cache::EncodedDepNodeIndex;
+use crate::query::on_disk_cache::OnDiskCache;
 use crate::query::{AsLocalKey, Key};
 use crate::thir;
 use crate::traits::query::{
@@ -38,13 +43,16 @@ use crate::ty::subst::{GenericArg, SubstsRef};
 use crate::ty::util::AlwaysRequiresDrop;
 use crate::ty::GeneratorDiagnosticData;
 use crate::ty::{self, CrateInherentImpls, ParamEnvAnd, Ty, TyCtxt, UnusedGenericParams};
+use measureme::StringId;
 use rustc_arena::TypedArena;
 use rustc_ast as ast;
 use rustc_ast::expand::allocator::AllocatorKind;
 use rustc_attr as attr;
+use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
 use rustc_data_structures::steal::Steal;
 use rustc_data_structures::svh::Svh;
+use rustc_data_structures::sync::AtomicU64;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::sync::WorkerLocal;
 use rustc_data_structures::unord::UnordSet;
@@ -58,6 +66,7 @@ use rustc_hir::hir_id::OwnerId;
 use rustc_hir::lang_items::{LangItem, LanguageItems};
 use rustc_hir::{Crate, ItemLocalId, TraitCandidate};
 use rustc_index::IndexVec;
+use rustc_query_system::ich::StableHashingContext;
 pub(crate) use rustc_query_system::query::QueryJobId;
 use rustc_query_system::query::*;
 use rustc_session::config::{EntryFnType, OptLevel, OutputFilenames, SymbolManglingVersion};
@@ -76,17 +85,70 @@ use std::ops::Deref;
 use std::path::PathBuf;
 use std::sync::Arc;
 
-use rustc_data_structures::fingerprint::Fingerprint;
-use rustc_query_system::ich::StableHashingContext;
+pub struct QueryKeyStringCache {
+    pub def_id_cache: FxHashMap<DefId, StringId>,
+}
+
+impl QueryKeyStringCache {
+    pub fn new() -> QueryKeyStringCache {
+        QueryKeyStringCache { def_id_cache: Default::default() }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub struct QueryStruct<'tcx> {
+    pub try_collect_active_jobs: fn(TyCtxt<'tcx>, &mut QueryMap<DepKind>) -> Option<()>,
+    pub alloc_self_profile_query_strings: fn(TyCtxt<'tcx>, &mut QueryKeyStringCache),
+    pub encode_query_results:
+        Option<fn(TyCtxt<'tcx>, &mut CacheEncoder<'_, 'tcx>, &mut EncodedDepNodeIndex)>,
+}
+
+pub struct QuerySystemFns<'tcx> {
+    pub engine: QueryEngine,
+    pub local_providers: Providers,
+    pub extern_providers: ExternProviders,
+    pub query_structs: Vec<QueryStruct<'tcx>>,
+    pub encode_query_results: fn(
+        tcx: TyCtxt<'tcx>,
+        encoder: &mut CacheEncoder<'_, 'tcx>,
+        query_result_index: &mut EncodedDepNodeIndex,
+    ),
+    pub try_mark_green: fn(tcx: TyCtxt<'tcx>, dep_node: &dep_graph::DepNode) -> bool,
+}
 
-#[derive(Default)]
 pub struct QuerySystem<'tcx> {
+    pub states: QueryStates<'tcx>,
     pub arenas: QueryArenas<'tcx>,
     pub caches: QueryCaches<'tcx>,
+
+    /// This provides access to the incremental compilation on-disk cache for query results.
+    /// Do not access this directly. It is only meant to be used by
+    /// `DepGraph::try_mark_green()` and the query infrastructure.
+    /// This is `None` if we are not incremental compilation mode
+    pub on_disk_cache: Option<OnDiskCache<'tcx>>,
+
+    pub fns: QuerySystemFns<'tcx>,
+
+    pub jobs: AtomicU64,
+
     // Since we erase query value types we tell the typesystem about them with `PhantomData`.
     _phantom_values: QueryPhantomValues<'tcx>,
 }
 
+impl<'tcx> QuerySystem<'tcx> {
+    pub fn new(fns: QuerySystemFns<'tcx>, on_disk_cache: Option<OnDiskCache<'tcx>>) -> Self {
+        QuerySystem {
+            states: Default::default(),
+            arenas: Default::default(),
+            caches: Default::default(),
+            on_disk_cache,
+            fns,
+            jobs: AtomicU64::new(1),
+            _phantom_values: Default::default(),
+        }
+    }
+}
+
 #[derive(Copy, Clone)]
 pub struct TyCtxtAt<'tcx> {
     pub tcx: TyCtxt<'tcx>,
@@ -136,7 +198,7 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     pub fn try_mark_green(self, dep_node: &dep_graph::DepNode) -> bool {
-        self.queries.try_mark_green(self, dep_node)
+        (self.query_system.fns.try_mark_green)(self, dep_node)
     }
 }
 
@@ -349,7 +411,7 @@ macro_rules! define_callbacks {
 
                 match try_get_cached(self.tcx, &self.tcx.query_system.caches.$name, &key) {
                     Some(_) => return,
-                    None => self.tcx.queries.$name(
+                    None => (self.tcx.query_system.fns.engine.$name)(
                         self.tcx,
                         DUMMY_SP,
                         key,
@@ -367,7 +429,7 @@ macro_rules! define_callbacks {
 
                 match try_get_cached(self.tcx, &self.tcx.query_system.caches.$name, &key) {
                     Some(_) => return,
-                    None => self.tcx.queries.$name(
+                    None => (self.tcx.query_system.fns.engine.$name)(
                         self.tcx,
                         DUMMY_SP,
                         key,
@@ -396,11 +458,22 @@ macro_rules! define_callbacks {
 
                 restore::<$V>(match try_get_cached(self.tcx, &self.tcx.query_system.caches.$name, &key) {
                     Some(value) => value,
-                    None => self.tcx.queries.$name(self.tcx, self.span, key, QueryMode::Get).unwrap(),
+                    None => (self.tcx.query_system.fns.engine.$name)(
+                        self.tcx,
+                        self.span,
+                        key, QueryMode::Get
+                    ).unwrap(),
                 })
             })*
         }
 
+        #[derive(Default)]
+        pub struct QueryStates<'tcx> {
+            $(
+                pub $name: QueryState<$($K)*, DepKind>,
+            )*
+        }
+
         pub struct Providers {
             $(pub $name: for<'tcx> fn(
                 TyCtxt<'tcx>,
@@ -446,19 +519,13 @@ macro_rules! define_callbacks {
             fn clone(&self) -> Self { *self }
         }
 
-        pub trait QueryEngine<'tcx>: rustc_data_structures::sync::Sync {
-            fn as_any(&'tcx self) -> &'tcx dyn std::any::Any;
-
-            fn try_mark_green(&'tcx self, tcx: TyCtxt<'tcx>, dep_node: &dep_graph::DepNode) -> bool;
-
-            $($(#[$attr])*
-            fn $name(
-                &'tcx self,
-                tcx: TyCtxt<'tcx>,
-                span: Span,
-                key: query_keys::$name<'tcx>,
-                mode: QueryMode,
-            ) -> Option<Erase<$V>>;)*
+        pub struct QueryEngine {
+            $(pub $name: for<'tcx> fn(
+                TyCtxt<'tcx>,
+                Span,
+                query_keys::$name<'tcx>,
+                QueryMode,
+            ) -> Option<Erase<$V>>,)*
         }
     };
 }

compiler/rustc_query_impl/src/lib.rs

@@ -11,36 +11,29 @@
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
 
-#[macro_use]
-extern crate rustc_macros;
 #[macro_use]
 extern crate rustc_middle;
 
-use rustc_data_structures::sync::AtomicU64;
+use crate::plumbing::{encode_all_query_results, try_mark_green};
 use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::{self, DepKind, DepKindStruct};
 use rustc_middle::query::erase::{erase, restore, Erase};
 use rustc_middle::query::AsLocalKey;
 use rustc_middle::ty::query::{
     query_keys, query_provided, query_provided_to_value, query_storage, query_values,
 };
-use rustc_middle::ty::query::{ExternProviders, Providers, QueryEngine};
+use rustc_middle::ty::query::{ExternProviders, Providers, QueryEngine, QuerySystemFns};
 use rustc_middle::ty::TyCtxt;
 use rustc_query_system::dep_graph::SerializedDepNodeIndex;
 use rustc_query_system::Value;
 use rustc_span::Span;
 
 #[macro_use]
 mod plumbing;
-pub use plumbing::QueryCtxt;
-use rustc_query_system::query::*;
-#[cfg(parallel_compiler)]
-pub use rustc_query_system::query::{deadlock, QueryContext};
+pub use crate::plumbing::QueryCtxt;
 
 pub use rustc_query_system::query::QueryConfig;
-
-mod on_disk_cache;
-pub use on_disk_cache::OnDiskCache;
+use rustc_query_system::query::*;
 
 mod profiling_support;
 pub use self::profiling_support::alloc_self_profile_query_strings;
@@ -54,9 +47,16 @@ trait QueryConfigRestored<'tcx>: QueryConfig<QueryCtxt<'tcx>> + Default {
 
 rustc_query_append! { define_queries! }
 
-impl<'tcx> Queries<'tcx> {
-    // Force codegen in the dyn-trait transformation in this crate.
-    pub fn as_dyn(&'tcx self) -> &'tcx dyn QueryEngine<'tcx> {
-        self
+pub fn query_system_fns<'tcx>(
+    local_providers: Providers,
+    extern_providers: ExternProviders,
+) -> QuerySystemFns<'tcx> {
+    QuerySystemFns {
+        engine: engine(),
+        local_providers,
+        extern_providers,
+        query_structs: make_dep_kind_array!(query_structs).to_vec(),
+        encode_query_results: encode_all_query_results,
+        try_mark_green: try_mark_green,
     }
 }

compiler/rustc_query_impl/src/plumbing.rs

@@ -1,24 +1,13 @@
-use crate::QueryCtxt;
 use measureme::{StringComponent, StringId};
-use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::profiling::SelfProfiler;
 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathData;
+use rustc_middle::ty::query::QueryKeyStringCache;
 use rustc_middle::ty::TyCtxt;
 use rustc_query_system::query::QueryCache;
 use std::fmt::Debug;
 use std::io::Write;
 
-pub(crate) struct QueryKeyStringCache {
-    def_id_cache: FxHashMap<DefId, StringId>,
-}
-
-impl QueryKeyStringCache {
-    fn new() -> QueryKeyStringCache {
-        QueryKeyStringCache { def_id_cache: Default::default() }
-    }
-}
-
 struct QueryKeyStringBuilder<'p, 'tcx> {
     profiler: &'p SelfProfiler,
     tcx: TyCtxt<'tcx>,
@@ -253,9 +242,8 @@ pub fn alloc_self_profile_query_strings(tcx: TyCtxt<'_>) {
     }
 
     let mut string_cache = QueryKeyStringCache::new();
-    let queries = QueryCtxt::from_tcx(tcx);
 
-    for query in &queries.queries.query_structs {
+    for query in &tcx.query_system.fns.query_structs {
         (query.alloc_self_profile_query_strings)(tcx, &mut string_cache);
     }
 }

compiler/rustc_query_impl/src/profiling_support.rs

@@ -1190,6 +1190,7 @@ impl Session {
 
     /// Returns the number of query threads that should be used for this
     /// compilation
+    #[inline]
     pub fn threads(&self) -> usize {
         self.opts.unstable_opts.threads
     }