]> git.lizzy.rs Git - rust.git/blobdiff - compiler/rustc_interface/src/queries.rs
Rollup merge of #106753 - compiler-errors:rpitit-not-suggestable, r=spastorino
[rust.git] / compiler / rustc_interface / src / queries.rs
index 1d0c7f5b7a388fab828bc2cfddffcb74da82bda9..041bb9eb7a1cbcd58b9239fa432b9784334fbc99 100644 (file)
@@ -5,6 +5,7 @@
 use rustc_ast as ast;
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_codegen_ssa::CodegenResults;
+use rustc_data_structures::steal::Steal;
 use rustc_data_structures::svh::Svh;
 use rustc_data_structures::sync::{Lrc, OnceCell, WorkerLocal};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_span::symbol::sym;
 use rustc_span::Symbol;
 use std::any::Any;
-use std::cell::{Ref, RefCell, RefMut};
+use std::cell::{RefCell, RefMut};
 use std::rc::Rc;
 use std::sync::Arc;
 
 /// Represent the result of a query.
 ///
-/// This result can be stolen with the [`take`] method and generated with the [`compute`] method.
+/// This result can be stolen once with the [`steal`] method and generated with the [`compute`] method.
 ///
-/// [`take`]: Self::take
+/// [`steal`]: Steal::steal
 /// [`compute`]: Self::compute
 pub struct Query<T> {
-    result: RefCell<Option<Result<T>>>,
+    /// `None` means no value has been computed yet.
+    result: RefCell<Option<Result<Steal<T>>>>,
 }
 
 impl<T> Query<T> {
-    fn compute<F: FnOnce() -> Result<T>>(&self, f: F) -> Result<&Query<T>> {
-        self.result.borrow_mut().get_or_insert_with(f).as_ref().map(|_| self).map_err(|&err| err)
+    fn compute<F: FnOnce() -> Result<T>>(&self, f: F) -> Result<QueryResult<'_, T>> {
+        RefMut::filter_map(
+            self.result.borrow_mut(),
+            |r: &mut Option<Result<Steal<T>>>| -> Option<&mut Steal<T>> {
+                r.get_or_insert_with(|| f().map(Steal::new)).as_mut().ok()
+            },
+        )
+        .map_err(|r| *r.as_ref().unwrap().as_ref().map(|_| ()).unwrap_err())
+        .map(QueryResult)
     }
+}
+
+pub struct QueryResult<'a, T>(RefMut<'a, Steal<T>>);
+
+impl<'a, T> std::ops::Deref for QueryResult<'a, T> {
+    type Target = RefMut<'a, Steal<T>>;
 
-    /// Takes ownership of the query result. Further attempts to take or peek the query
-    /// result will panic unless it is generated by calling the `compute` method.
-    pub fn take(&self) -> T {
-        self.result.borrow_mut().take().expect("missing query result").unwrap()
+    fn deref(&self) -> &Self::Target {
+        &self.0
     }
+}
 
-    /// Borrows the query result using the RefCell. Panics if the result is stolen.
-    pub fn peek(&self) -> Ref<'_, T> {
-        Ref::map(self.result.borrow(), |r| {
-            r.as_ref().unwrap().as_ref().expect("missing query result")
-        })
+impl<'a, T> std::ops::DerefMut for QueryResult<'a, T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
     }
+}
 
-    /// Mutably borrows the query result using the RefCell. Panics if the result is stolen.
-    pub fn peek_mut(&self) -> RefMut<'_, T> {
-        RefMut::map(self.result.borrow_mut(), |r| {
-            r.as_mut().unwrap().as_mut().expect("missing query result")
-        })
+impl<'a, 'tcx> QueryResult<'a, QueryContext<'tcx>> {
+    pub fn enter<T>(mut self, f: impl FnOnce(TyCtxt<'tcx>) -> T) -> T {
+        (*self.0).get_mut().enter(f)
     }
 }
 
@@ -111,24 +122,24 @@ fn codegen_backend(&self) -> &Lrc<Box<dyn CodegenBackend>> {
         self.compiler.codegen_backend()
     }
 
-    fn dep_graph_future(&self) -> Result<&Query<Option<DepGraphFuture>>> {
+    fn dep_graph_future(&self) -> Result<QueryResult<'_, Option<DepGraphFuture>>> {
         self.dep_graph_future.compute(|| {
             let sess = self.session();
             Ok(sess.opts.build_dep_graph().then(|| rustc_incremental::load_dep_graph(sess)))
         })
     }
 
-    pub fn parse(&self) -> Result<&Query<ast::Crate>> {
+    pub fn parse(&self) -> Result<QueryResult<'_, ast::Crate>> {
         self.parse.compute(|| {
             passes::parse(self.session(), &self.compiler.input)
                 .map_err(|mut parse_error| parse_error.emit())
         })
     }
 
-    pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, Lrc<LintStore>)>> {
+    pub fn register_plugins(&self) -> Result<QueryResult<'_, (ast::Crate, Lrc<LintStore>)>> {
         self.register_plugins.compute(|| {
-            let crate_name = *self.crate_name()?.peek();
-            let krate = self.parse()?.take();
+            let crate_name = *self.crate_name()?.borrow();
+            let krate = self.parse()?.steal();
 
             let empty: &(dyn Fn(&Session, &mut LintStore) + Sync + Send) = &|_, _| {};
             let (krate, lint_store) = passes::register_plugins(
@@ -150,11 +161,11 @@ pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, Lrc<LintStore>)>> {
         })
     }
 
-    pub fn crate_name(&self) -> Result<&Query<Symbol>> {
+    pub fn crate_name(&self) -> Result<QueryResult<'_, Symbol>> {
         self.crate_name.compute(|| {
             Ok({
                 let parse_result = self.parse()?;
-                let krate = parse_result.peek();
+                let krate = parse_result.borrow();
                 // parse `#[crate_name]` even if `--crate-name` was passed, to make sure it matches.
                 find_crate_name(self.session(), &krate.attrs, &self.compiler.input)
             })
@@ -163,11 +174,12 @@ pub fn crate_name(&self) -> Result<&Query<Symbol>> {
 
     pub fn expansion(
         &self,
-    ) -> Result<&Query<(Lrc<ast::Crate>, Rc<RefCell<BoxedResolver>>, Lrc<LintStore>)>> {
+    ) -> Result<QueryResult<'_, (Lrc<ast::Crate>, Rc<RefCell<BoxedResolver>>, Lrc<LintStore>)>>
+    {
         trace!("expansion");
         self.expansion.compute(|| {
-            let crate_name = *self.crate_name()?.peek();
-            let (krate, lint_store) = self.register_plugins()?.take();
+            let crate_name = *self.crate_name()?.borrow();
+            let (krate, lint_store) = self.register_plugins()?.steal();
             let _timer = self.session().timer("configure_and_expand");
             let sess = self.session();
             let mut resolver = passes::create_resolver(
@@ -183,10 +195,10 @@ pub fn expansion(
         })
     }
 
-    fn dep_graph(&self) -> Result<&Query<DepGraph>> {
+    fn dep_graph(&self) -> Result<QueryResult<'_, DepGraph>> {
         self.dep_graph.compute(|| {
             let sess = self.session();
-            let future_opt = self.dep_graph_future()?.take();
+            let future_opt = self.dep_graph_future()?.steal();
             let dep_graph = future_opt
                 .and_then(|future| {
                     let (prev_graph, prev_work_products) =
@@ -199,10 +211,11 @@ fn dep_graph(&self) -> Result<&Query<DepGraph>> {
         })
     }
 
-    pub fn prepare_outputs(&self) -> Result<&Query<OutputFilenames>> {
+    pub fn prepare_outputs(&self) -> Result<QueryResult<'_, OutputFilenames>> {
         self.prepare_outputs.compute(|| {
-            let (krate, boxed_resolver, _) = &*self.expansion()?.peek();
-            let crate_name = *self.crate_name()?.peek();
+            let expansion = self.expansion()?;
+            let (krate, boxed_resolver, _) = &*expansion.borrow();
+            let crate_name = *self.crate_name()?.borrow();
             passes::prepare_outputs(
                 self.session(),
                 self.compiler,
@@ -213,12 +226,12 @@ pub fn prepare_outputs(&self) -> Result<&Query<OutputFilenames>> {
         })
     }
 
-    pub fn global_ctxt(&'tcx self) -> Result<&Query<QueryContext<'tcx>>> {
+    pub fn global_ctxt(&'tcx self) -> Result<QueryResult<'_, QueryContext<'tcx>>> {
         self.global_ctxt.compute(|| {
-            let crate_name = *self.crate_name()?.peek();
-            let outputs = self.prepare_outputs()?.take();
-            let dep_graph = self.dep_graph()?.peek().clone();
-            let (krate, resolver, lint_store) = self.expansion()?.take();
+            let crate_name = *self.crate_name()?.borrow();
+            let outputs = self.prepare_outputs()?.steal();
+            let dep_graph = self.dep_graph()?.borrow().clone();
+            let (krate, resolver, lint_store) = self.expansion()?.steal();
             Ok(passes::create_global_ctxt(
                 self.compiler,
                 lint_store,
@@ -235,9 +248,9 @@ pub fn global_ctxt(&'tcx self) -> Result<&Query<QueryContext<'tcx>>> {
         })
     }
 
-    pub fn ongoing_codegen(&'tcx self) -> Result<&Query<Box<dyn Any>>> {
+    pub fn ongoing_codegen(&'tcx self) -> Result<QueryResult<'_, Box<dyn Any>>> {
         self.ongoing_codegen.compute(|| {
-            self.global_ctxt()?.peek_mut().enter(|tcx| {
+            self.global_ctxt()?.enter(|tcx| {
                 tcx.analysis(()).ok();
 
                 // Don't do code generation if there were any errors
@@ -293,12 +306,10 @@ pub fn linker(&'tcx self) -> Result<Linker> {
         let sess = self.session().clone();
         let codegen_backend = self.codegen_backend().clone();
 
-        let dep_graph = self.dep_graph()?.peek().clone();
-        let (crate_hash, prepare_outputs) = self
-            .global_ctxt()?
-            .peek_mut()
-            .enter(|tcx| (tcx.crate_hash(LOCAL_CRATE), tcx.output_filenames(()).clone()));
-        let ongoing_codegen = self.ongoing_codegen()?.take();
+        let (crate_hash, prepare_outputs, dep_graph) = self.global_ctxt()?.enter(|tcx| {
+            (tcx.crate_hash(LOCAL_CRATE), tcx.output_filenames(()).clone(), tcx.dep_graph.clone())
+        });
+        let ongoing_codegen = self.ongoing_codegen()?.steal();
 
         Ok(Linker {
             sess,
@@ -382,6 +393,7 @@ pub fn enter<F, T>(&self, f: F) -> T
         // NOTE: intentionally does not compute the global context if it hasn't been built yet,
         // since that likely means there was a parse error.
         if let Some(Ok(gcx)) = &mut *queries.global_ctxt.result.borrow_mut() {
+            let gcx = gcx.get_mut();
             // We assume that no queries are run past here. If there are new queries
             // after this point, they'll show up as "<unknown>" in self-profiling data.
             {