diff options
Diffstat (limited to 'tests/run-make-fulldeps/obtain-borrowck')
| -rw-r--r-- | tests/run-make-fulldeps/obtain-borrowck/Makefile | 26 | ||||
| -rw-r--r-- | tests/run-make-fulldeps/obtain-borrowck/driver.rs | 161 | ||||
| -rw-r--r-- | tests/run-make-fulldeps/obtain-borrowck/output.stdout | 8 | ||||
| -rw-r--r-- | tests/run-make-fulldeps/obtain-borrowck/test.rs | 32 |
4 files changed, 227 insertions, 0 deletions
diff --git a/tests/run-make-fulldeps/obtain-borrowck/Makefile b/tests/run-make-fulldeps/obtain-borrowck/Makefile new file mode 100644 index 000000000..212d0f67d --- /dev/null +++ b/tests/run-make-fulldeps/obtain-borrowck/Makefile @@ -0,0 +1,26 @@ +include ../tools.mk + +# This example shows how to implement a rustc driver that retrieves MIR bodies +# together with the borrow checker information. + +# How to run this +# $ ./x.py test tests/run-make-fulldeps/obtain-borrowck + +DRIVER_BINARY := "$(TMPDIR)"/driver +SYSROOT := $(shell $(RUSTC) --print sysroot) + +ifdef IS_WINDOWS +LIBSTD := -L "$(SYSROOT)\\lib\\rustlib\\$(TARGET)\\lib" +else +LIBSTD := +endif + +all: + $(RUSTC) driver.rs -o "$(DRIVER_BINARY)" + $(TARGET_RPATH_ENV) "$(DRIVER_BINARY)" --sysroot $(SYSROOT) $(LIBSTD) test.rs -o "$(TMPDIR)/driver_test" > "$(TMPDIR)"/output.stdout + +ifdef RUSTC_BLESS_TEST + cp "$(TMPDIR)"/output.stdout output.stdout +else + $(DIFF) output.stdout "$(TMPDIR)"/output.stdout +endif diff --git a/tests/run-make-fulldeps/obtain-borrowck/driver.rs b/tests/run-make-fulldeps/obtain-borrowck/driver.rs new file mode 100644 index 000000000..9cd504f00 --- /dev/null +++ b/tests/run-make-fulldeps/obtain-borrowck/driver.rs @@ -0,0 +1,161 @@ +#![feature(rustc_private)] + +//! This program implements a rustc driver that retrieves MIR bodies with +//! borrowck information. This cannot be done in a straightforward way because +//! `get_body_with_borrowck_facts`–the function for retrieving a MIR body with +//! borrowck facts–can panic if the body is stolen before it is invoked. +//! Therefore, the driver overrides `mir_borrowck` query (this is done in the +//! `config` callback), which retrieves the body that is about to be borrow +//! checked and stores it in a thread local `MIR_BODIES`. Then, `after_analysis` +//! callback triggers borrow checking of all MIR bodies by retrieving +//! `optimized_mir` and pulls out the MIR bodies with the borrowck information +//! from the thread local storage. + +extern crate rustc_borrowck; +extern crate rustc_driver; +extern crate rustc_hir; +extern crate rustc_interface; +extern crate rustc_middle; +extern crate rustc_session; + +use rustc_borrowck::consumers::BodyWithBorrowckFacts; +use rustc_driver::Compilation; +use rustc_hir::def_id::LocalDefId; +use rustc_hir::def::DefKind; +use rustc_interface::interface::Compiler; +use rustc_interface::{Config, Queries}; +use rustc_middle::ty::query::query_values::mir_borrowck; +use rustc_middle::ty::query::{ExternProviders, Providers}; +use rustc_middle::ty::{self, TyCtxt}; +use rustc_session::Session; +use std::cell::RefCell; +use std::collections::HashMap; +use std::thread_local; + +fn main() { + let exit_code = rustc_driver::catch_with_exit_code(move || { + let mut rustc_args: Vec<_> = std::env::args().collect(); + // We must pass -Zpolonius so that the borrowck information is computed. + rustc_args.push("-Zpolonius".to_owned()); + let mut callbacks = CompilerCalls::default(); + // Call the Rust compiler with our callbacks. + rustc_driver::RunCompiler::new(&rustc_args, &mut callbacks).run() + }); + std::process::exit(exit_code); +} + +#[derive(Default)] +pub struct CompilerCalls; + +impl rustc_driver::Callbacks for CompilerCalls { + // In this callback we override the mir_borrowck query. + fn config(&mut self, config: &mut Config) { + assert!(config.override_queries.is_none()); + config.override_queries = Some(override_queries); + } + + // In this callback we trigger borrow checking of all functions and obtain + // the result. + fn after_analysis<'tcx>( + &mut self, + compiler: &Compiler, + queries: &'tcx Queries<'tcx>, + ) -> Compilation { + compiler.session().abort_if_errors(); + queries.global_ctxt().unwrap().enter(|tcx| { + // Collect definition ids of MIR bodies. + let hir = tcx.hir(); + let mut bodies = Vec::new(); + + let crate_items = tcx.hir_crate_items(()); + for id in crate_items.items() { + if matches!(tcx.def_kind(id.owner_id), DefKind::Fn) { + bodies.push(id.owner_id); + } + } + + for id in crate_items.trait_items() { + if matches!(tcx.def_kind(id.owner_id), DefKind::AssocFn) { + let trait_item = hir.trait_item(id); + if let rustc_hir::TraitItemKind::Fn(_, trait_fn) = &trait_item.kind { + if let rustc_hir::TraitFn::Provided(_) = trait_fn { + bodies.push(trait_item.owner_id); + } + } + } + } + + for id in crate_items.impl_items() { + if matches!(tcx.def_kind(id.owner_id), DefKind::AssocFn) { + bodies.push(id.owner_id); + } + } + + // Trigger borrow checking of all bodies. + for def_id in bodies { + let _ = tcx.optimized_mir(def_id); + } + + // See what bodies were borrow checked. + let mut bodies = get_bodies(tcx); + bodies.sort_by(|(def_id1, _), (def_id2, _)| def_id1.cmp(def_id2)); + println!("Bodies retrieved for:"); + for (def_id, body) in bodies { + println!("{}", def_id); + assert!(body.input_facts.cfg_edge.len() > 0); + } + }); + + Compilation::Continue + } +} + +fn override_queries(_session: &Session, local: &mut Providers, _external: &mut ExternProviders) { + local.mir_borrowck = mir_borrowck; +} + +// Since mir_borrowck does not have access to any other state, we need to use a +// thread-local for storing the obtained MIR bodies. +// +// Note: We are using 'static lifetime here, which is in general unsound. +// Unfortunately, that is the only lifetime allowed here. Our use is safe +// because we cast it back to `'tcx` before using. +thread_local! { + pub static MIR_BODIES: + RefCell<HashMap<LocalDefId, BodyWithBorrowckFacts<'static>>> = + RefCell::new(HashMap::new()); +} + +fn mir_borrowck<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> mir_borrowck<'tcx> { + let body_with_facts = rustc_borrowck::consumers::get_body_with_borrowck_facts( + tcx, + ty::WithOptConstParam::unknown(def_id), + ); + // SAFETY: The reader casts the 'static lifetime to 'tcx before using it. + let body_with_facts: BodyWithBorrowckFacts<'static> = + unsafe { std::mem::transmute(body_with_facts) }; + MIR_BODIES.with(|state| { + let mut map = state.borrow_mut(); + assert!(map.insert(def_id, body_with_facts).is_none()); + }); + let mut providers = Providers::default(); + rustc_borrowck::provide(&mut providers); + let original_mir_borrowck = providers.mir_borrowck; + original_mir_borrowck(tcx, def_id) +} + +/// Pull MIR bodies stored in the thread-local. +fn get_bodies<'tcx>(tcx: TyCtxt<'tcx>) -> Vec<(String, BodyWithBorrowckFacts<'tcx>)> { + MIR_BODIES.with(|state| { + let mut map = state.borrow_mut(); + map.drain() + .map(|(def_id, body)| { + let def_path = tcx.def_path(def_id.to_def_id()); + // SAFETY: For soundness we need to ensure that the bodies have + // the same lifetime (`'tcx`), which they had before they were + // stored in the thread local. + (def_path.to_string_no_crate_verbose(), unsafe { std::mem::transmute(body) }) + }) + .collect() + }) +} diff --git a/tests/run-make-fulldeps/obtain-borrowck/output.stdout b/tests/run-make-fulldeps/obtain-borrowck/output.stdout new file mode 100644 index 000000000..e011622e6 --- /dev/null +++ b/tests/run-make-fulldeps/obtain-borrowck/output.stdout @@ -0,0 +1,8 @@ +Bodies retrieved for: +::X::provided +::foo +::main +::main::{constant#0} +::{impl#0}::new +::{impl#1}::provided +::{impl#1}::required diff --git a/tests/run-make-fulldeps/obtain-borrowck/test.rs b/tests/run-make-fulldeps/obtain-borrowck/test.rs new file mode 100644 index 000000000..f7b4b41fe --- /dev/null +++ b/tests/run-make-fulldeps/obtain-borrowck/test.rs @@ -0,0 +1,32 @@ +trait X { + fn provided(&self) -> usize { + 5 + } + fn required(&self) -> u32; +} + +struct Bar; + +impl Bar { + fn new() -> Self { + Self + } +} + +impl X for Bar { + fn provided(&self) -> usize { + 1 + } + fn required(&self) -> u32 { + 7 + } +} + +const fn foo() -> usize { + 1 +} + +fn main() { + let bar: [Bar; foo()] = [Bar::new()]; + assert_eq!(bar[0].provided(), foo()); +} |