Make non-queries available to rustc_with_all_queries.

nnethercote · nnethercote · commit 253c6965bc56 · 2026-03-02T15:26:41.000+11:00
`rustc_with_all_queries` currently provides information about all
queries. Also, a caller can provide an ad hoc list of extra non-queries.
This is used by `define_queries` for non-query dep kinds: `Null`, `Red`,
etc. This is pretty hacky.

This commit changes `rustc_with_all_queries` so that the non-queries
information is available to all callers. (Some callers ignore the
non-query information.) This is done by adding `non_query` entries to
the primary list of queries in `rustc_queries!`.
diff --git a/compiler/rustc_macros/src/query.rs b/compiler/rustc_macros/src/query.rs
@@ -10,6 +10,7 @@ use syn::{
 };
 
 mod kw {
+    syn::custom_keyword!(non_query);
     syn::custom_keyword!(query);
 }
 
@@ -54,12 +55,37 @@ struct Query {
     modifiers: QueryModifiers,
 }
 
-impl Parse for Query {
+/// Declaration of a non-query dep kind.
+/// ```ignore (illustrative)
+/// /// Doc comment for `MyNonQuery`.
+/// //  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^  doc_comments
+/// non_query MyNonQuery
+/// //        ^^^^^^^^^^               name
+/// ```
+struct NonQuery {
+    doc_comments: Vec<Attribute>,
+    name: Ident,
+}
+
+enum QueryEntry {
+    Query(Query),
+    NonQuery(NonQuery),
+}
+
+impl Parse for QueryEntry {
     fn parse(input: ParseStream<'_>) -> Result<Self> {
         let mut doc_comments = check_attributes(input.call(Attribute::parse_outer)?)?;
 
+        // Try the non-query case first.
+        if input.parse::<kw::non_query>().is_ok() {
+            let name: Ident = input.parse()?;
+            return Ok(QueryEntry::NonQuery(NonQuery { doc_comments, name }));
+        }
+
         // Parse the query declaration. Like `query type_of(key: DefId) -> Ty<'tcx>`
-        input.parse::<kw::query>()?;
+        if input.parse::<kw::query>().is_err() {
+            return Err(input.error("expected `query` or `non_query`"));
+        }
         let name: Ident = input.parse()?;
 
         // `(key: DefId)`
@@ -84,7 +110,7 @@ impl Parse for Query {
             doc_comments.push(doc_comment_from_desc(&modifiers.desc.expr_list)?);
         }
 
-        Ok(Query { doc_comments, modifiers, name, key_pat, key_ty, return_ty })
+        Ok(QueryEntry::Query(Query { doc_comments, modifiers, name, key_pat, key_ty, return_ty }))
     }
 }
 
@@ -375,9 +401,9 @@ fn add_to_analyzer_stream(query: &Query, analyzer_stream: &mut proc_macro2::Toke
     // macro producing a higher order macro that has all its token in the macro declaration we lose
     // any meaningful spans, resulting in rust-analyzer being unable to make the connection between
     // the query name and the corresponding providers field. The trick to fix this is to have
-    // `rustc_queries` emit a field access with the given name's span which allows it to successfully
-    // show references / go to definition to the corresponding provider assignment which is usually
-    // the more interesting place.
+    // `rustc_queries` emit a field access with the given name's span which allows it to
+    // successfully show references / go to definition to the corresponding provider assignment
+    // which is usually the more interesting place.
     let ra_hint = quote! {
         let crate::query::Providers { #name: _, .. };
     };
@@ -393,9 +419,10 @@ fn add_to_analyzer_stream(query: &Query, analyzer_stream: &mut proc_macro2::Toke
 }
 
 pub(super) fn rustc_queries(input: TokenStream) -> TokenStream {
-    let queries = parse_macro_input!(input as List<Query>);
+    let queries = parse_macro_input!(input as List<QueryEntry>);
 
     let mut query_stream = quote! {};
+    let mut non_query_stream = quote! {};
     let mut helpers = HelperTokenStreams::default();
     let mut analyzer_stream = quote! {};
     let mut errors = quote! {};
@@ -411,6 +438,18 @@ pub(super) fn rustc_queries(input: TokenStream) -> TokenStream {
     }
 
     for query in queries.0 {
+        let query = match query {
+            QueryEntry::Query(query) => query,
+            QueryEntry::NonQuery(NonQuery { doc_comments, name }) => {
+                // Get the exceptional non-query case out of the way first.
+                non_query_stream.extend(quote! {
+                    #(#doc_comments)*
+                    #name,
+                });
+                continue;
+            }
+        };
+
         let Query { doc_comments, name, key_ty, return_ty, modifiers, .. } = &query;
 
         // Normalize an absent return type into `-> ()` to make macro-rules parsing easier.
@@ -486,24 +525,18 @@ pub(super) fn rustc_queries(input: TokenStream) -> TokenStream {
     let HelperTokenStreams { description_fns_stream, cache_on_disk_if_fns_stream } = helpers;
 
     TokenStream::from(quote! {
-        /// Higher-order macro that invokes the specified macro with a prepared
-        /// list of all query signatures (including modifiers).
-        ///
-        /// This allows multiple simpler macros to each have access to the list
-        /// of queries.
+        /// Higher-order macro that invokes the specified macro with (a) a list of all query
+        /// signatures (including modifiers), and (b) a list of non-query names. This allows
+        /// multiple simpler macros to each have access to these lists.
         #[macro_export]
         macro_rules! rustc_with_all_queries {
             (
-                // The macro to invoke once, on all queries (plus extras).
+                // The macro to invoke once, on all queries and non-queries.
                 $macro:ident!
-
-                // Within [], an optional list of extra "query" signatures to
-                // pass to the given macro, in addition to the actual queries.
-                $( [$($extra_fake_queries:tt)*] )?
             ) => {
                 $macro! {
-                    $( $($extra_fake_queries)* )?
-                    #query_stream
+                    queries { #query_stream }
+                    non_queries { #non_query_stream }
                 }
             }
         }
diff --git a/compiler/rustc_middle/src/dep_graph/dep_node.rs b/compiler/rustc_middle/src/dep_graph/dep_node.rs
@@ -270,15 +270,26 @@ impl StableOrd for WorkProductId {
 // Note: `$K` and `$V` are unused but present so this can be called by `rustc_with_all_queries`.
 macro_rules! define_dep_nodes {
     (
-        $(
-            $(#[$attr:meta])*
-            [$($modifiers:tt)*] fn $variant:ident($K:ty) -> $V:ty,
-        )*
+        queries {
+            $(
+                $(#[$q_attr:meta])*
+                [$($modifiers:tt)*]
+                fn $q_name:ident($K:ty) -> $V:ty,
+            )*
+        }
+        non_queries {
+            $(
+                $(#[$nq_attr:meta])*
+                $nq_name:ident,
+            )*
+        }
     ) => {
-
         #[macro_export]
         macro_rules! make_dep_kind_array {
-            ($mod:ident) => {[ $($mod::$variant()),* ]};
+            ($mod:ident) => {[
+                $( $mod::$nq_name(), )*
+                $( $mod::$q_name(), )*
+            ]};
         }
 
         /// This enum serves as an index into arrays built by `make_dep_kind_array`.
@@ -290,14 +301,18 @@ macro_rules! define_dep_nodes {
         #[allow(non_camel_case_types)]
         #[repr(u16)] // Must be kept in sync with the rest of `DepKind`.
         pub enum DepKind {
-            $( $( #[$attr] )* $variant),*
+            $( $(#[$nq_attr])* $nq_name, )*
+            $( $(#[$q_attr])* $q_name, )*
         }
 
         // This computes the number of dep kind variants. Along the way, it sanity-checks that the
         // discriminants of the variants have been assigned consecutively from 0 so that they can
         // be used as a dense index, and that all discriminants fit in a `u16`.
         pub(crate) const DEP_KIND_NUM_VARIANTS: u16 = {
-            let deps = &[$(DepKind::$variant,)*];
+            let deps = &[
+                $(DepKind::$nq_name,)*
+                $(DepKind::$q_name,)*
+            ];
             let mut i = 0;
             while i < deps.len() {
                 if i != deps[i].as_usize() {
@@ -311,7 +326,8 @@ macro_rules! define_dep_nodes {
 
         pub(super) fn dep_kind_from_label_string(label: &str) -> Result<DepKind, ()> {
             match label {
-                $( stringify!($variant) => Ok(self::DepKind::$variant), )*
+                $( stringify!($nq_name) => Ok(self::DepKind::$nq_name), )*
+                $( stringify!($q_name) => Ok(self::DepKind::$q_name), )*
                 _ => Err(()),
             }
         }
@@ -320,27 +336,14 @@ macro_rules! define_dep_nodes {
         /// DepNode groups for tests.
         #[expect(non_upper_case_globals)]
         pub mod label_strs {
-            $( pub const $variant: &str = stringify!($variant); )*
+            $( pub const $nq_name: &str = stringify!($nq_name); )*
+            $( pub const $q_name: &str = stringify!($q_name); )*
         }
     };
 }
 
-// Create various data structures for each query, and also for a few things
-// that aren't queries. The key and return types aren't used, hence the use of `()`.
-rustc_with_all_queries!(define_dep_nodes![
-    /// We use this for most things when incr. comp. is turned off.
-    [] fn Null(()) -> (),
-    /// We use this to create a forever-red node.
-    [] fn Red(()) -> (),
-    /// We use this to create a side effect node.
-    [] fn SideEffect(()) -> (),
-    /// We use this to create the anon node with zero dependencies.
-    [] fn AnonZeroDeps(()) -> (),
-    [] fn TraitSelect(()) -> (),
-    [] fn CompileCodegenUnit(()) -> (),
-    [] fn CompileMonoItem(()) -> (),
-    [] fn Metadata(()) -> (),
-]);
+// Create various data structures for each query, and also for a few things that aren't queries.
+rustc_with_all_queries! { define_dep_nodes! }
 
 // WARNING: `construct` is generic and does not know that `CompileCodegenUnit` takes `Symbol`s as keys.
 // Be very careful changing this type signature!
diff --git a/compiler/rustc_middle/src/queries.rs b/compiler/rustc_middle/src/queries.rs
@@ -2771,6 +2771,23 @@ rustc_queries! {
         cache_on_disk_if { *cnum == LOCAL_CRATE }
         separate_provide_extern
     }
+
+    //-----------------------------------------------------------------------------
+    // "Non-queries" are special dep kinds that are not queries.
+    //-----------------------------------------------------------------------------
+
+    /// We use this for most things when incr. comp. is turned off.
+    non_query Null
+    /// We use this to create a forever-red node.
+    non_query Red
+    /// We use this to create a side effect node.
+    non_query SideEffect
+    /// We use this to create the anon node with zero dependencies.
+    non_query AnonZeroDeps
+    non_query TraitSelect
+    non_query CompileCodegenUnit
+    non_query CompileMonoItem
+    non_query Metadata
 }
 
 rustc_with_all_queries! { define_callbacks! }
diff --git a/compiler/rustc_middle/src/query/plumbing.rs b/compiler/rustc_middle/src/query/plumbing.rs
@@ -378,11 +378,15 @@ macro_rules! define_callbacks {
     (
         // You might expect the key to be `$K:ty`, but it needs to be `$($K:tt)*` so that
         // `query_helper_param_ty!` can match on specific type names.
-        $(
-            $(#[$attr:meta])*
-            [$($modifiers:tt)*]
-            fn $name:ident($($K:tt)*) -> $V:ty,
-        )*
+        queries {
+            $(
+                $(#[$attr:meta])*
+                [$($modifiers:tt)*]
+                fn $name:ident($($K:tt)*) -> $V:ty,
+            )*
+        }
+        // Non-queries are unused here.
+        non_queries { $($_:tt)* }
     ) => {
         $(
             #[allow(unused_lifetimes)]
diff --git a/compiler/rustc_query_impl/src/plumbing.rs b/compiler/rustc_query_impl/src/plumbing.rs
@@ -414,15 +414,20 @@ pub(crate) fn force_from_dep_node_inner<'tcx, Q: GetQueryVTable<'tcx>>(
     }
 }
 
-// Note: `$K` and `$V` are unused but present so this can be called by `rustc_with_all_queries`.
 macro_rules! define_queries {
     (
-        $(
-            $(#[$attr:meta])*
-            [$($modifiers:tt)*] fn $name:ident($K:ty) -> $V:ty,
-        )*
+        // Note: `$K` and `$V` are unused but present so this can be called by
+        // `rustc_with_all_queries`.
+        queries {
+            $(
+                $(#[$attr:meta])*
+                [$($modifiers:tt)*]
+                fn $name:ident($K:ty) -> $V:ty,
+            )*
+        }
+        // Non-queries are unused here.
+        non_queries { $($_:tt)* }
     ) => {
-
         pub(crate) mod query_impl { $(pub(crate) mod $name {
             use super::super::*;
             use ::rustc_middle::query::erase::{self, Erased};
