use crate::build::{BlockAnd, BlockAndExtension, BlockFrame, Builder, CFG};
use crate::thir::{Expr, ExprRef, LintLevel};
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_data_structures::fx::FxHashMap;
use rustc_index::vec::IndexVec;
use rustc_middle::middle::region;
use rustc_middle::mir::*;
/// end of the vector (top of the stack) first.
drops: Vec<DropData>,
+ moved_locals: Vec<Local>,
+
/// The drop index that will drop everything in and below this scope on an
/// unwind path.
cached_unwind_block: Option<DropIdx>,
region_scope: region_scope.0,
region_scope_span: region_scope.1.span,
drops: vec![],
+ moved_locals: vec![],
cached_unwind_block: None,
cached_generator_drop_block: None,
});
assert_eq!(scope.region_scope, local_scope, "local scope is not the topmost scope!",);
// look for moves of a local variable, like `MOVE(_X)`
- let locals_moved = operands
- .iter()
- .filter_map(|operand| match operand {
- Operand::Copy(_) | Operand::Constant(_) => None,
- Operand::Move(place) => place.as_local(),
- })
- .collect::<FxHashSet<_>>();
+ let locals_moved = operands.iter().flat_map(|operand| match operand {
+ Operand::Copy(_) | Operand::Constant(_) => None,
+ Operand::Move(place) => place.as_local(),
+ });
- // Remove the drops for the moved operands.
- scope
- .drops
- .retain(|drop| drop.kind == DropKind::Storage || !locals_moved.contains(&drop.local));
- scope.invalidate_cache();
+ for local in locals_moved {
+ // check if we have a Drop for this operand and -- if so
+ // -- add it to the list of moved operands. Note that this
+ // local might not have been an operand created for this
+ // call, it could come from other places too.
+ if scope.drops.iter().any(|drop| drop.local == local && drop.kind == DropKind::Value) {
+ scope.moved_locals.push(local);
+ }
+ }
}
// Other
debug_assert_eq!(unwind_drops.drops[unwind_to].0.kind, drop_data.kind);
unwind_to = unwind_drops.drops[unwind_to].1;
+ // If the operand has been moved, and we are not on an unwind
+ // path, then don't generate the drop. (We only take this into
+ // account for non-unwind paths so as not to disturb the
+ // caching mechanism.)
+ if scope.moved_locals.iter().any(|&o| o == local) {
+ continue;
+ }
+
unwind_drops.add_entry(block, unwind_to);
let next = cfg.start_new_block();
StorageLive(_1); // scope 0 at $DIR/box_expr.rs:7:9: 7:10
StorageLive(_2); // scope 0 at $DIR/box_expr.rs:7:13: 7:25
_2 = Box(S); // scope 0 at $DIR/box_expr.rs:7:13: 7:25
- (*_2) = S::new() -> [return: bb1, unwind: bb6]; // scope 0 at $DIR/box_expr.rs:7:17: 7:25
+ (*_2) = S::new() -> [return: bb1, unwind: bb7]; // scope 0 at $DIR/box_expr.rs:7:17: 7:25
// mir::Constant
// + span: $DIR/box_expr.rs:7:17: 7:23
// + literal: Const { ty: fn() -> S {S::new}, val: Value(Scalar(<ZST>)) }
}
bb5 (cleanup): {
- drop(_1) -> bb7; // scope 0 at $DIR/box_expr.rs:9:1: 9:2
+ drop(_4) -> bb6; // scope 1 at $DIR/box_expr.rs:8:11: 8:12
}
bb6 (cleanup): {
- drop(_2) -> bb7; // scope 0 at $DIR/box_expr.rs:7:24: 7:25
+ drop(_1) -> bb8; // scope 0 at $DIR/box_expr.rs:9:1: 9:2
}
bb7 (cleanup): {
+ drop(_2) -> bb8; // scope 0 at $DIR/box_expr.rs:7:24: 7:25
+ }
+
+ bb8 (cleanup): {
resume; // scope 0 at $DIR/box_expr.rs:6:1: 9:2
}
}
let mut _2: S; // in scope 0 at $DIR/issue-41110.rs:8:13: 8:14
let mut _3: S; // in scope 0 at $DIR/issue-41110.rs:8:21: 8:27
let mut _4: S; // in scope 0 at $DIR/issue-41110.rs:8:21: 8:22
+ let mut _5: bool; // in scope 0 at $DIR/issue-41110.rs:8:27: 8:28
scope 1 {
debug x => _1; // in scope 1 at $DIR/issue-41110.rs:8:9: 8:10
}
bb0: {
+ _5 = const false; // scope 0 at $DIR/issue-41110.rs:8:9: 8:10
StorageLive(_1); // scope 0 at $DIR/issue-41110.rs:8:9: 8:10
StorageLive(_2); // scope 0 at $DIR/issue-41110.rs:8:13: 8:14
+ _5 = const true; // scope 0 at $DIR/issue-41110.rs:8:13: 8:14
_2 = S; // scope 0 at $DIR/issue-41110.rs:8:13: 8:14
StorageLive(_3); // scope 0 at $DIR/issue-41110.rs:8:21: 8:27
StorageLive(_4); // scope 0 at $DIR/issue-41110.rs:8:21: 8:22
_4 = S; // scope 0 at $DIR/issue-41110.rs:8:21: 8:22
- _3 = S::id(move _4) -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/issue-41110.rs:8:21: 8:27
+ _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue-41110.rs:8:21: 8:27
// mir::Constant
// + span: $DIR/issue-41110.rs:8:23: 8:25
// + literal: Const { ty: fn(S) -> S {S::id}, val: Value(Scalar(<ZST>)) }
bb1: {
StorageDead(_4); // scope 0 at $DIR/issue-41110.rs:8:26: 8:27
- _1 = S::other(move _2, move _3) -> bb2; // scope 0 at $DIR/issue-41110.rs:8:13: 8:28
+ _5 = const false; // scope 0 at $DIR/issue-41110.rs:8:13: 8:28
+ _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue-41110.rs:8:13: 8:28
// mir::Constant
// + span: $DIR/issue-41110.rs:8:15: 8:20
// + literal: Const { ty: fn(S, S) {S::other}, val: Value(Scalar(<ZST>)) }
bb2: {
StorageDead(_3); // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
+ _5 = const false; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
StorageDead(_2); // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
_0 = const (); // scope 0 at $DIR/issue-41110.rs:7:11: 9:2
StorageDead(_1); // scope 0 at $DIR/issue-41110.rs:9:1: 9:2
}
bb3 (cleanup): {
- drop(_2) -> bb4; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
+ goto -> bb5; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
}
bb4 (cleanup): {
+ goto -> bb5; // scope 0 at $DIR/issue-41110.rs:8:26: 8:27
+ }
+
+ bb5 (cleanup): {
+ goto -> bb8; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
+ }
+
+ bb6 (cleanup): {
resume; // scope 0 at $DIR/issue-41110.rs:7:1: 9:2
}
+
+ bb7 (cleanup): {
+ drop(_2) -> bb6; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
+ }
+
+ bb8 (cleanup): {
+ switchInt(_5) -> [false: bb6, otherwise: bb7]; // scope 0 at $DIR/issue-41110.rs:8:27: 8:28
+ }
}
StorageLive(_5); // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
_6 = const false; // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
_5 = move _1; // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
- goto -> bb11; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
+ goto -> bb12; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
}
bb2: {
bb3: {
StorageDead(_5); // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
_0 = const (); // scope 0 at $DIR/issue-41110.rs:14:15: 19:2
- drop(_2) -> [return: bb4, unwind: bb8]; // scope 1 at $DIR/issue-41110.rs:19:1: 19:2
+ drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue-41110.rs:19:1: 19:2
}
bb4: {
}
bb6 (cleanup): {
- goto -> bb7; // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
+ goto -> bb8; // scope 2 at $DIR/issue-41110.rs:18:9: 18:10
}
bb7 (cleanup): {
- goto -> bb8; // scope 1 at $DIR/issue-41110.rs:19:1: 19:2
+ goto -> bb8; // scope 2 at $DIR/issue-41110.rs:17:11: 17:12
}
bb8 (cleanup): {
- goto -> bb13; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
+ goto -> bb9; // scope 1 at $DIR/issue-41110.rs:19:1: 19:2
}
bb9 (cleanup): {
- resume; // scope 0 at $DIR/issue-41110.rs:14:1: 19:2
+ goto -> bb14; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
}
bb10 (cleanup): {
+ resume; // scope 0 at $DIR/issue-41110.rs:14:1: 19:2
+ }
+
+ bb11 (cleanup): {
_2 = move _5; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
goto -> bb6; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
}
- bb11: {
+ bb12: {
_2 = move _5; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
goto -> bb2; // scope 2 at $DIR/issue-41110.rs:18:5: 18:6
}
- bb12 (cleanup): {
- drop(_1) -> bb9; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
+ bb13 (cleanup): {
+ drop(_1) -> bb10; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
}
- bb13 (cleanup): {
- switchInt(_6) -> [false: bb9, otherwise: bb12]; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
+ bb14 (cleanup): {
+ switchInt(_6) -> [false: bb10, otherwise: bb13]; // scope 0 at $DIR/issue-41110.rs:19:1: 19:2
}
}
bb1: {
StorageDead(_3); // scope 0 at $DIR/no-spurious-drop-after-call.rs:9:33: 9:34
- _1 = std::mem::drop::<String>(move _2) -> bb2; // scope 0 at $DIR/no-spurious-drop-after-call.rs:9:5: 9:35
+ _1 = std::mem::drop::<String>(move _2) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/no-spurious-drop-after-call.rs:9:5: 9:35
// mir::Constant
// + span: $DIR/no-spurious-drop-after-call.rs:9:5: 9:19
// + literal: Const { ty: fn(std::string::String) {std::mem::drop::<std::string::String>}, val: Value(Scalar(<ZST>)) }
_0 = const (); // scope 0 at $DIR/no-spurious-drop-after-call.rs:8:11: 10:2
return; // scope 0 at $DIR/no-spurious-drop-after-call.rs:10:2: 10:2
}
+
+ bb3 (cleanup): {
+ drop(_2) -> bb4; // scope 0 at $DIR/no-spurious-drop-after-call.rs:9:34: 9:35
+ }
+
+ bb4 (cleanup): {
+ resume; // scope 0 at $DIR/no-spurious-drop-after-call.rs:8:1: 10:2
+ }
}