Rollup merge of rust-lang#56507 - nikomatsakis:polonius-integrate, r=matthewjasper

polonius tweaks

- bump polonius to 0.6.0
- fix 2-phase-borrow activations

r? @matthewjasper

Author: pietroalbini

Cargo.lock

@@ -1587,7 +1587,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "polonius-engine"
-version = "0.5.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "datafrog 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1966,7 +1966,7 @@ dependencies = [
  "lazy_static 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "polonius-engine 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-rayon-core 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_apfloat 0.0.0",
@@ -2406,7 +2406,7 @@ dependencies = [
  "graphviz 0.0.0",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "log_settings 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "polonius-engine 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc_apfloat 0.0.0",
  "rustc_data_structures 0.0.0",
@@ -3427,7 +3427,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum phf_generator 0.7.22 (registry+https://github.com/rust-lang/crates.io-index)" = "05a079dd052e7b674d21cb31cbb6c05efd56a2cd2827db7692e2f1a507ebd998"
 "checksum phf_shared 0.7.22 (registry+https://github.com/rust-lang/crates.io-index)" = "c2261d544c2bb6aa3b10022b0be371b9c7c64f762ef28c6f5d4f1ef6d97b5930"
 "checksum pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
-"checksum polonius-engine 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a5b6b0a7f5f4278b991ffd14abce1d01b013121ad297460237ef0a2f08d43201"
+"checksum polonius-engine 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "494cc28002fae8ce2604c31c5cc1e73009318a0f6d2bb539a018dc22420a2dd0"
 "checksum precomputed-hash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
 "checksum pretty_assertions 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3a029430f0d744bc3d15dd474d591bed2402b645d024583082b9f63bb936dac6"
 "checksum pretty_env_logger 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "ed8d1e63042e889b85228620629b51c011d380eed2c7e0015f8a644def280c28"

src/librustc/Cargo.toml

@@ -17,7 +17,7 @@ jobserver = "0.1"
 lazy_static = "1.0.0"
 scoped-tls = { version = "0.1.1", features = ["nightly"] }
 log = { version = "0.4", features = ["release_max_level_info", "std"] }
-polonius-engine = "0.5.0"
+polonius-engine = "0.6.0"
 rustc-rayon = "0.1.1"
 rustc-rayon-core = "0.1.1"
 rustc_apfloat = { path = "../librustc_apfloat" }

src/librustc_mir/Cargo.toml

@@ -15,7 +15,7 @@ either = "1.5.0"
 graphviz = { path = "../libgraphviz" }
 log = "0.4"
 log_settings = "0.1.1"
-polonius-engine = "0.5.0"
+polonius-engine = "0.6.0"
 rustc = { path = "../librustc" }
 rustc_target = { path = "../librustc_target" }
 rustc_data_structures = { path = "../librustc_data_structures" }

src/librustc_mir/borrow_check/nll/invalidation.rs

@@ -66,10 +66,14 @@ struct InvalidationGenerator<'cx, 'tcx: 'cx, 'gcx: 'tcx> {
 /// Visits the whole MIR and generates invalidates() facts
 /// Most of the code implementing this was stolen from borrow_check/mod.rs
 impl<'cx, 'tcx, 'gcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx, 'gcx> {
-    fn visit_statement(&mut self,
-                       block: BasicBlock,
-                       statement: &Statement<'tcx>,
-                       location: Location) {
+    fn visit_statement(
+        &mut self,
+        block: BasicBlock,
+        statement: &Statement<'tcx>,
+        location: Location,
+    ) {
+        self.check_activations(location);
+
         match statement.kind {
             StatementKind::Assign(ref lhs, ref rhs) => {
                 self.consume_rvalue(
@@ -159,6 +163,8 @@ impl<'cx, 'tcx, 'gcx> Visitor<'tcx> for InvalidationGenerator<'cx, 'tcx, 'gcx> {
         terminator: &Terminator<'tcx>,
         location: Location
     ) {
+        self.check_activations(location);
+
         match terminator.kind {
             TerminatorKind::SwitchInt {
                 ref discr,
@@ -482,5 +488,41 @@ impl<'cg, 'cx, 'tcx, 'gcx> InvalidationGenerator<'cx, 'tcx, 'gcx> {
         let lidx = self.location_table.start_index(l);
         self.all_facts.invalidates.push((lidx, b));
     }
+
+    fn check_activations(
+        &mut self,
+        location: Location,
+    ) {
+        if !self.tcx.two_phase_borrows() {
+            return;
+        }
+
+        // Two-phase borrow support: For each activation that is newly
+        // generated at this statement, check if it interferes with
+        // another borrow.
+        for &borrow_index in self.borrow_set.activations_at_location(location) {
+            let borrow = &self.borrow_set[borrow_index];
+
+            // only mutable borrows should be 2-phase
+            assert!(match borrow.kind {
+                BorrowKind::Shared | BorrowKind::Shallow => false,
+                BorrowKind::Unique | BorrowKind::Mut { .. } => true,
+            });
+
+            self.access_place(
+                ContextKind::Activation.new(location),
+                &borrow.borrowed_place,
+                (
+                    Deep,
+                    Activation(WriteKind::MutableBorrow(borrow.kind), borrow_index),
+                ),
+                LocalMutationIsAllowed::No,
+            );
+
+            // We do not need to call `check_if_path_or_subpath_is_moved`
+            // again, as we already called it when we made the
+            // initial reservation.
+        }
+    }
 }