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::{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 arena: WorkerLocal<Arena<'tcx>>,
71 dep_graph_future: Query<Option<DepGraphFuture>>,
72 parse: Query<ast::Crate>,
73 crate_name: Query<String>,
74 register_plugins: Query<(ast::Crate, Lrc<LintStore>)>,
75 expansion: Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>,
76 dep_graph: Query<DepGraph>,
77 lower_to_hir: Query<(&'tcx map::Forest<'tcx>, Steal<ResolverOutputs>)>,
78 prepare_outputs: Query<OutputFilenames>,
79 global_ctxt: Query<QueryContext<'tcx>>,
80 ongoing_codegen: Query<Box<dyn Any>>,
83 impl<'tcx> Queries<'tcx> {
84 pub fn new(compiler: &'tcx Compiler) -> Queries<'tcx> {
88 arena: WorkerLocal::new(|_| Arena::default()),
89 dep_graph_future: Default::default(),
90 parse: Default::default(),
91 crate_name: Default::default(),
92 register_plugins: Default::default(),
93 expansion: Default::default(),
94 dep_graph: Default::default(),
95 lower_to_hir: Default::default(),
96 prepare_outputs: Default::default(),
97 global_ctxt: Default::default(),
98 ongoing_codegen: Default::default(),
102 fn session(&self) -> &Lrc<Session> {
105 fn codegen_backend(&self) -> &Lrc<Box<dyn CodegenBackend>> {
106 &self.compiler.codegen_backend()
109 pub fn dep_graph_future(&self) -> Result<&Query<Option<DepGraphFuture>>> {
110 self.dep_graph_future.compute(|| {
115 .then(|| rustc_incremental::load_dep_graph(self.session())))
119 pub fn parse(&self) -> Result<&Query<ast::Crate>> {
120 self.parse.compute(|| {
121 passes::parse(self.session(), &self.compiler.input).map_err(|mut parse_error| {
128 pub fn register_plugins(&self) -> Result<&Query<(ast::Crate, Lrc<LintStore>)>> {
129 self.register_plugins.compute(|| {
130 let crate_name = self.crate_name()?.peek().clone();
131 let krate = self.parse()?.take();
133 let empty: &(dyn Fn(&Session, &mut LintStore) + Sync + Send) = &|_, _| {};
134 let result = passes::register_plugins(
136 &*self.codegen_backend().metadata_loader(),
137 self.compiler.register_lints.as_ref().map(|p| &**p).unwrap_or_else(|| empty),
142 // Compute the dependency graph (in the background). We want to do
143 // this as early as possible, to give the DepGraph maximum time to
144 // load before dep_graph() is called, but it also can't happen
145 // until after rustc_incremental::prepare_session_directory() is
146 // called, which happens within passes::register_plugins().
147 self.dep_graph_future().ok();
153 pub fn crate_name(&self) -> Result<&Query<String>> {
154 self.crate_name.compute(|| {
155 Ok(match self.compiler.crate_name {
156 Some(ref crate_name) => crate_name.clone(),
158 let parse_result = self.parse()?;
159 let krate = parse_result.peek();
160 rustc_codegen_utils::link::find_crate_name(
161 Some(self.session()),
163 &self.compiler.input,
172 ) -> Result<&Query<(ast::Crate, Steal<Rc<RefCell<BoxedResolver>>>, Lrc<LintStore>)>> {
173 self.expansion.compute(|| {
174 let crate_name = self.crate_name()?.peek().clone();
175 let (krate, lint_store) = self.register_plugins()?.take();
176 let _timer = self.session().timer("configure_and_expand");
177 passes::configure_and_expand(
178 self.session().clone(),
180 self.codegen_backend().metadata_loader(),
184 .map(|(krate, resolver)| {
185 (krate, Steal::new(Rc::new(RefCell::new(resolver))), lint_store)
190 pub fn dep_graph(&self) -> Result<&Query<DepGraph>> {
191 self.dep_graph.compute(|| {
192 Ok(match self.dep_graph_future()?.take() {
193 None => DepGraph::new_disabled(),
195 let (prev_graph, prev_work_products) =
196 self.session().time("blocked_on_dep_graph_loading", || {
199 .unwrap_or_else(|e| rustc_incremental::LoadResult::Error {
200 message: format!("could not decode incremental cache: {:?}", e),
202 .open(self.session())
204 DepGraph::new(prev_graph, prev_work_products)
212 ) -> Result<&Query<(&'tcx map::Forest<'tcx>, Steal<ResolverOutputs>)>> {
213 self.lower_to_hir.compute(|| {
214 let expansion_result = self.expansion()?;
215 let peeked = expansion_result.peek();
216 let krate = &peeked.0;
217 let resolver = peeked.1.steal();
218 let lint_store = &peeked.2;
219 let hir = resolver.borrow_mut().access(|resolver| {
220 passes::lower_to_hir(
224 &*self.dep_graph()?.peek(),
229 let hir = self.arena.alloc(hir);
230 Ok((hir, Steal::new(BoxedResolver::to_resolver_outputs(resolver))))
234 pub fn prepare_outputs(&self) -> Result<&Query<OutputFilenames>> {
235 self.prepare_outputs.compute(|| {
236 let expansion_result = self.expansion()?;
237 let (krate, boxed_resolver, _) = &*expansion_result.peek();
238 let crate_name = self.crate_name()?;
239 let crate_name = crate_name.peek();
240 passes::prepare_outputs(
250 pub fn global_ctxt(&'tcx self) -> Result<&Query<QueryContext<'tcx>>> {
251 self.global_ctxt.compute(|| {
252 let crate_name = self.crate_name()?.peek().clone();
253 let outputs = self.prepare_outputs()?.peek().clone();
254 let lint_store = self.expansion()?.peek().2.clone();
255 let hir = self.lower_to_hir()?.peek();
256 let (ref hir_forest, ref resolver_outputs) = &*hir;
257 let _timer = self.session().timer("create_global_ctxt");
258 Ok(passes::create_global_ctxt(
262 resolver_outputs.steal(),
271 pub fn ongoing_codegen(&'tcx self) -> Result<&Query<Box<dyn Any>>> {
272 self.ongoing_codegen.compute(|| {
273 let outputs = self.prepare_outputs()?;
274 self.global_ctxt()?.peek_mut().enter(|tcx| {
275 tcx.analysis(LOCAL_CRATE).ok();
277 // Don't do code generation if there were any errors
278 self.session().compile_status()?;
280 Ok(passes::start_codegen(&***self.codegen_backend(), tcx, &*outputs.peek()))
285 pub fn linker(&'tcx self) -> Result<Linker> {
286 let dep_graph = self.dep_graph()?;
287 let prepare_outputs = self.prepare_outputs()?;
288 let ongoing_codegen = self.ongoing_codegen()?;
290 let sess = self.session().clone();
291 let codegen_backend = self.codegen_backend().clone();
295 dep_graph: dep_graph.peek().clone(),
296 prepare_outputs: prepare_outputs.take(),
297 ongoing_codegen: ongoing_codegen.take(),
306 prepare_outputs: OutputFilenames,
307 ongoing_codegen: Box<dyn Any>,
308 codegen_backend: Lrc<Box<dyn CodegenBackend>>,
312 pub fn link(self) -> Result<()> {
315 .join_codegen_and_link(
316 self.ongoing_codegen,
319 &self.prepare_outputs,
321 .map_err(|_| ErrorReported);
322 let prof = self.sess.prof.clone();
323 let dep_graph = self.dep_graph;
324 prof.generic_activity("drop_dep_graph").run(move || drop(dep_graph));
330 pub fn enter<F, T>(&self, f: F) -> T
332 F: for<'tcx> FnOnce(&'tcx Queries<'tcx>) -> T,
334 let mut _timer = None;
335 let queries = Queries::new(&self);
336 let ret = f(&queries);
338 if self.session().opts.debugging_opts.query_stats {
339 if let Ok(gcx) = queries.global_ctxt() {
340 gcx.peek().print_stats();
344 _timer = Some(self.session().timer("free_global_ctxt"));
349 // This method is different to all the other methods in `Compiler` because
350 // it lacks a `Queries` entry. It's also not currently used. It does serve
351 // as an example of how `Compiler` can be used, with additional steps added
352 // between some passes. And see `rustc_driver::run_compiler` for a more
354 pub fn compile(&self) -> Result<()> {
355 let linker = self.enter(|queries| {
356 queries.prepare_outputs()?;
358 if self.session().opts.output_types.contains_key(&OutputType::DepInfo)
359 && self.session().opts.output_types.len() == 1
364 queries.global_ctxt()?;
366 // Drop AST after creating GlobalCtxt to free memory.
367 mem::drop(queries.expansion()?.take());
369 queries.ongoing_codegen()?;
371 let linker = queries.linker()?;
375 if let Some(linker) = linker {