1 use crate::interface::{Compiler, Result};
2 use crate::passes::{self, BoxedResolver, QueryContext};
4 use rustc::arena::Arena;
5 use rustc::dep_graph::DepGraph;
7 use rustc::session::config::{OutputFilenames, OutputType};
8 use rustc::session::Session;
9 use rustc::ty::steal::Steal;
10 use rustc::ty::{AllArenas, GlobalCtxt, ResolverOutputs};
11 use rustc::util::common::ErrorReported;
12 use rustc_codegen_utils::codegen_backend::CodegenBackend;
13 use rustc_data_structures::sync::{Lrc, Once, WorkerLocal};
14 use rustc_hir::def_id::LOCAL_CRATE;
15 use rustc_incremental::DepGraphFuture;
16 use rustc_lint::LintStore;
18 use std::cell::{Ref, RefCell, RefMut};
21 use syntax::{self, ast};
23 /// Represent the result of a query.
24 /// This result can be stolen with the `take` method and generated with the `compute` method.
26 result: RefCell<Option<Result<T>>>,
30 fn compute<F: FnOnce() -> Result<T>>(&self, f: F) -> Result<&Query<T>> {
31 let mut result = self.result.borrow_mut();
35 result.as_ref().unwrap().as_ref().map(|_| self).map_err(|err| *err)
38 /// Takes ownership of the query result. Further attempts to take or peek the query
39 /// result will panic unless it is generated by calling the `compute` method.
40 pub fn take(&self) -> T {
41 self.result.borrow_mut().take().expect("missing query result").unwrap()
44 /// Borrows the query result using the RefCell. Panics if the result is stolen.
45 pub fn peek(&self) -> Ref<'_, T> {
46 Ref::map(self.result.borrow(), |r| {
47 r.as_ref().unwrap().as_ref().expect("missing query result")
51 /// Mutably borrows the query result using the RefCell. Panics if the result is stolen.
52 pub fn peek_mut(&self) -> RefMut<'_, T> {
53 RefMut::map(self.result.borrow_mut(), |r| {
54 r.as_mut().unwrap().as_mut().expect("missing query result")
59 impl<T> Default for Query<T> {
60 fn default() -> Self {
61 Query { result: RefCell::new(None) }
65 pub struct Queries<'tcx> {
66 compiler: &'tcx Compiler,
67 gcx: Once<GlobalCtxt<'tcx>>,
69 all_arenas: AllArenas,
70 arena: WorkerLocal<Arena<'tcx>>,
72 dep_graph_future: Query<Option<DepGraphFuture>>,
73 parse: Query<ast::Crate>,
74 crate_name: Query<String>,
75 register_plugins: Query<(ast::Crate, Lrc<LintStore>)>,
76 expansion: Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>,
77 dep_graph: Query<DepGraph>,
78 lower_to_hir: Query<(&'tcx map::Forest<'tcx>, Steal<ResolverOutputs>)>,
79 prepare_outputs: Query<OutputFilenames>,
80 global_ctxt: Query<QueryContext<'tcx>>,
81 ongoing_codegen: Query<Box<dyn Any>>,
84 impl<'tcx> Queries<'tcx> {
85 pub fn new(compiler: &'tcx Compiler) -> Queries<'tcx> {
89 all_arenas: AllArenas::new(),
90 arena: WorkerLocal::new(|_| Arena::default()),
91 dep_graph_future: Default::default(),
92 parse: Default::default(),
93 crate_name: Default::default(),
94 register_plugins: Default::default(),
95 expansion: Default::default(),
96 dep_graph: Default::default(),
97 lower_to_hir: Default::default(),
98 prepare_outputs: Default::default(),
99 global_ctxt: Default::default(),
100 ongoing_codegen: Default::default(),
104 fn session(&self) -> &Lrc<Session> {
107 fn codegen_backend(&self) -> &Lrc<Box<dyn CodegenBackend>> {
108 &self.compiler.codegen_backend()
111 pub fn dep_graph_future(&self) -> Result<&Query<Option<DepGraphFuture>>> {
112 self.dep_graph_future.compute(|| {
117 .then(|| rustc_incremental::load_dep_graph(self.session())))
121 pub fn parse(&self) -> Result<&Query<ast::Crate>> {
122 self.parse.compute(|| {
123 passes::parse(self.session(), &self.compiler.input).map_err(|mut parse_error| {
130 pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, Lrc<LintStore>)>> {
131 self.register_plugins.compute(|| {
132 let crate_name = self.crate_name()?.peek().clone();
133 let krate = self.parse()?.take();
135 let empty: &(dyn Fn(&Session, &mut LintStore) + Sync + Send) = &|_, _| {};
136 let result = passes::register_plugins(
138 &*self.codegen_backend().metadata_loader(),
139 self.compiler.register_lints.as_ref().map(|p| &**p).unwrap_or_else(|| empty),
144 // Compute the dependency graph (in the background). We want to do
145 // this as early as possible, to give the DepGraph maximum time to
146 // load before dep_graph() is called, but it also can't happen
147 // until after rustc_incremental::prepare_session_directory() is
148 // called, which happens within passes::register_plugins().
149 self.dep_graph_future().ok();
155 pub fn crate_name(&self) -> Result<&Query<String>> {
156 self.crate_name.compute(|| {
157 Ok(match self.compiler.crate_name {
158 Some(ref crate_name) => crate_name.clone(),
160 let parse_result = self.parse()?;
161 let krate = parse_result.peek();
162 rustc_codegen_utils::link::find_crate_name(
163 Some(self.session()),
165 &self.compiler.input,
174 ) -> Result<&Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>> {
175 self.expansion.compute(|| {
176 let crate_name = self.crate_name()?.peek().clone();
177 let (krate, lint_store) = self.register_plugins()?.take();
178 let _timer = self.session().timer("configure_and_expand");
179 passes::configure_and_expand(
180 self.session().clone(),
182 self.codegen_backend().metadata_loader(),
186 .map(|(krate, resolver)| {
187 (krate, Steal::new(Rc::new(RefCell::new(resolver))), lint_store)
192 pub fn dep_graph(&self) -> Result<&Query<DepGraph>> {
193 self.dep_graph.compute(|| {
194 Ok(match self.dep_graph_future()?.take() {
195 None => DepGraph::new_disabled(),
197 let (prev_graph, prev_work_products) =
198 self.session().time("blocked_on_dep_graph_loading", || {
201 .unwrap_or_else(|e| rustc_incremental::LoadResult::Error {
202 message: format!("could not decode incremental cache: {:?}", e),
204 .open(self.session())
206 DepGraph::new(prev_graph, prev_work_products)
214 ) -> Result<&Query<(&'tcx map::Forest<'tcx>, Steal<ResolverOutputs>)>> {
215 self.lower_to_hir.compute(|| {
216 let expansion_result = self.expansion()?;
217 let peeked = expansion_result.peek();
218 let krate = &peeked.0;
219 let resolver = peeked.1.steal();
220 let lint_store = &peeked.2;
221 let hir = resolver.borrow_mut().access(|resolver| {
222 passes::lower_to_hir(
226 &*self.dep_graph()?.peek(),
231 let hir = self.arena.alloc(hir);
232 Ok((hir, Steal::new(BoxedResolver::to_resolver_outputs(resolver))))
236 pub fn prepare_outputs(&self) -> Result<&Query<OutputFilenames>> {
237 self.prepare_outputs.compute(|| {
238 let expansion_result = self.expansion()?;
239 let (krate, boxed_resolver, _) = &*expansion_result.peek();
240 let crate_name = self.crate_name()?;
241 let crate_name = crate_name.peek();
242 passes::prepare_outputs(
252 pub fn global_ctxt(&'tcx self) -> Result<&Query<QueryContext<'tcx>>> {
253 self.global_ctxt.compute(|| {
254 let crate_name = self.crate_name()?.peek().clone();
255 let outputs = self.prepare_outputs()?.peek().clone();
256 let lint_store = self.expansion()?.peek().2.clone();
257 let hir = self.lower_to_hir()?.peek();
258 let (ref hir_forest, ref resolver_outputs) = &*hir;
259 let _timer = self.session().timer("create_global_ctxt");
260 Ok(passes::create_global_ctxt(
264 resolver_outputs.steal(),
274 pub fn ongoing_codegen(&'tcx self) -> Result<&Query<Box<dyn Any>>> {
275 self.ongoing_codegen.compute(|| {
276 let outputs = self.prepare_outputs()?;
277 self.global_ctxt()?.peek_mut().enter(|tcx| {
278 tcx.analysis(LOCAL_CRATE).ok();
280 // Don't do code generation if there were any errors
281 self.session().compile_status()?;
283 Ok(passes::start_codegen(&***self.codegen_backend(), tcx, &*outputs.peek()))
288 pub fn linker(&'tcx self) -> Result<Linker> {
289 let dep_graph = self.dep_graph()?;
290 let prepare_outputs = self.prepare_outputs()?;
291 let ongoing_codegen = self.ongoing_codegen()?;
293 let sess = self.session().clone();
294 let codegen_backend = self.codegen_backend().clone();
298 dep_graph: dep_graph.peek().clone(),
299 prepare_outputs: prepare_outputs.take(),
300 ongoing_codegen: ongoing_codegen.take(),
309 prepare_outputs: OutputFilenames,
310 ongoing_codegen: Box<dyn Any>,
311 codegen_backend: Lrc<Box<dyn CodegenBackend>>,
315 pub fn link(self) -> Result<()> {
318 .join_codegen_and_link(
319 self.ongoing_codegen,
322 &self.prepare_outputs,
324 .map_err(|_| ErrorReported);
325 let prof = self.sess.prof.clone();
326 let dep_graph = self.dep_graph;
327 prof.generic_activity("drop_dep_graph").run(move || drop(dep_graph));
333 pub fn enter<F, T>(&self, f: F) -> T
335 F: for<'tcx> FnOnce(&'tcx Queries<'tcx>) -> T,
337 let mut _timer = None;
338 let queries = Queries::new(&self);
339 let ret = f(&queries);
341 if self.session().opts.debugging_opts.query_stats {
342 if let Ok(gcx) = queries.global_ctxt() {
343 gcx.peek().print_stats();
347 _timer = Some(self.session().timer("free_global_ctxt"));
352 // This method is different to all the other methods in `Compiler` because
353 // it lacks a `Queries` entry. It's also not currently used. It does serve
354 // as an example of how `Compiler` can be used, with additional steps added
355 // between some passes. And see `rustc_driver::run_compiler` for a more
357 pub fn compile(&self) -> Result<()> {
358 let linker = self.enter(|queries| {
359 queries.prepare_outputs()?;
361 if self.session().opts.output_types.contains_key(&OutputType::DepInfo)
362 && self.session().opts.output_types.len() == 1
367 queries.global_ctxt()?;
369 // Drop AST after creating GlobalCtxt to free memory.
370 mem::drop(queries.expansion()?.take());
372 queries.ongoing_codegen()?;
374 let linker = queries.linker()?;
378 if let Some(linker) = linker {