diff options
| -rw-r--r-- | compiler/rustc_mir_dataflow/src/lib.rs | 1 | ||||
| -rw-r--r-- | compiler/rustc_mir_dataflow/src/value_analysis.rs | 173 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/dataflow_const_prop.rs | 103 | ||||
| -rw-r--r-- | tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff | 26 | ||||
| -rw-r--r-- | tests/mir-opt/dataflow-const-prop/enum.rs | 45 | ||||
| -rw-r--r-- | tests/mir-opt/dataflow-const-prop/enum.simple.DataflowConstProp.diff (renamed from tests/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff) | 16 |
6 files changed, 305 insertions, 59 deletions
diff --git a/compiler/rustc_mir_dataflow/src/lib.rs b/compiler/rustc_mir_dataflow/src/lib.rs index 7f40cfca32f..3e382f500af 100644 --- a/compiler/rustc_mir_dataflow/src/lib.rs +++ b/compiler/rustc_mir_dataflow/src/lib.rs @@ -1,6 +1,7 @@ #![feature(associated_type_defaults)] #![feature(box_patterns)] #![feature(exact_size_is_empty)] +#![feature(let_chains)] #![feature(min_specialization)] #![feature(once_cell)] #![feature(stmt_expr_attributes)] diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs index 8003da6bbd2..03b6c182062 100644 --- a/compiler/rustc_mir_dataflow/src/value_analysis.rs +++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs @@ -65,10 +65,8 @@ pub trait ValueAnalysis<'tcx> { StatementKind::Assign(box (place, rvalue)) => { self.handle_assign(*place, rvalue, state); } - StatementKind::SetDiscriminant { .. } => { - // Could treat this as writing a constant to a pseudo-place. - // But discriminants are currently not tracked, so we do nothing. - // Related: https://github.com/rust-lang/unsafe-code-guidelines/issues/84 + StatementKind::SetDiscriminant { box ref place, .. } => { + state.flood_discr(place.as_ref(), self.map()); } StatementKind::Intrinsic(box intrinsic) => { self.handle_intrinsic(intrinsic, state); @@ -447,26 +445,29 @@ impl<V: Clone + HasTop + HasBottom> State<V> { } pub fn flood_with(&mut self, place: PlaceRef<'_>, map: &Map, value: V) { - if let Some(root) = map.find(place) { - self.flood_idx_with(root, map, value); - } + let StateData::Reachable(values) = &mut self.0 else { return }; + map.for_each_aliasing_place(place, None, &mut |place| { + if let Some(vi) = map.places[place].value_index { + values[vi] = value.clone(); + } + }); } pub fn flood(&mut self, place: PlaceRef<'_>, map: &Map) { self.flood_with(place, map, V::top()) } - pub fn flood_idx_with(&mut self, place: PlaceIndex, map: &Map, value: V) { + pub fn flood_discr_with(&mut self, place: PlaceRef<'_>, map: &Map, value: V) { let StateData::Reachable(values) = &mut self.0 else { return }; - map.preorder_invoke(place, &mut |place| { + map.for_each_aliasing_place(place, Some(TrackElem::Discriminant), &mut |place| { if let Some(vi) = map.places[place].value_index { values[vi] = value.clone(); } }); } - pub fn flood_idx(&mut self, place: PlaceIndex, map: &Map) { - self.flood_idx_with(place, map, V::top()) + pub fn flood_discr(&mut self, place: PlaceRef<'_>, map: &Map) { + self.flood_discr_with(place, map, V::top()) } /// Copies `source` to `target`, including all tracked places beneath. @@ -474,7 +475,9 @@ impl<V: Clone + HasTop + HasBottom> State<V> { /// If `target` contains a place that is not contained in `source`, it will be overwritten with /// Top. Also, because this will copy all entries one after another, it may only be used for /// places that are non-overlapping or identical. - pub fn assign_place_idx(&mut self, target: PlaceIndex, source: PlaceIndex, map: &Map) { + /// + /// The target place must have been flooded before calling this method. + fn assign_place_idx(&mut self, target: PlaceIndex, source: PlaceIndex, map: &Map) { let StateData::Reachable(values) = &mut self.0 else { return }; // If both places are tracked, we copy the value to the target. If the target is tracked, @@ -492,26 +495,28 @@ impl<V: Clone + HasTop + HasBottom> State<V> { let projection = map.places[target_child].proj_elem.unwrap(); if let Some(source_child) = map.projections.get(&(source, projection)) { self.assign_place_idx(target_child, *source_child, map); - } else { - self.flood_idx(target_child, map); } } } pub fn assign(&mut self, target: PlaceRef<'_>, result: ValueOrPlace<V>, map: &Map) { + self.flood(target, map); if let Some(target) = map.find(target) { self.assign_idx(target, result, map); - } else { - // We don't track this place nor any projections, assignment can be ignored. } } + pub fn assign_discr(&mut self, target: PlaceRef<'_>, result: ValueOrPlace<V>, map: &Map) { + self.flood_discr(target, map); + if let Some(target) = map.find_discr(target) { + self.assign_idx(target, result, map); + } + } + + /// The target place must have been flooded before calling this method. pub fn assign_idx(&mut self, target: PlaceIndex, result: ValueOrPlace<V>, map: &Map) { match result { ValueOrPlace::Value(value) => { - // First flood the target place in case we also track any projections (although - // this scenario is currently not well-supported by the API). - self.flood_idx(target, map); let StateData::Reachable(values) = &mut self.0 else { return }; if let Some(value_index) = map.places[target].value_index { values[value_index] = value; @@ -526,6 +531,14 @@ impl<V: Clone + HasTop + HasBottom> State<V> { map.find(place).map(|place| self.get_idx(place, map)).unwrap_or(V::top()) } + /// Retrieve the value stored for a place, or ⊤ if it is not tracked. + pub fn get_discr(&self, place: PlaceRef<'_>, map: &Map) -> V { + match map.find_discr(place) { + Some(place) => self.get_idx(place, map), + None => V::top(), + } + } + /// Retrieve the value stored for a place index, or ⊤ if it is not tracked. pub fn get_idx(&self, place: PlaceIndex, map: &Map) -> V { match &self.0 { @@ -582,7 +595,6 @@ impl Map { /// This is currently the only way to create a [`Map`]. The way in which the tracked places are /// chosen is an implementation detail and may not be relied upon (other than that their type /// passes the filter). - #[instrument(skip_all, level = "debug")] pub fn from_filter<'tcx>( tcx: TyCtxt<'tcx>, body: &Body<'tcx>, @@ -614,7 +626,7 @@ impl Map { /// Potentially register the (local, projection) place and its fields, recursively. /// - /// Invariant: The projection must only contain fields. + /// Invariant: The projection must only contain trackable elements. fn register_with_filter_rec<'tcx>( &mut self, tcx: TyCtxt<'tcx>, @@ -623,21 +635,46 @@ impl Map { ty: Ty<'tcx>, filter: &mut impl FnMut(Ty<'tcx>) -> bool, ) { - if filter(ty) { - // We know that the projection only contains trackable elements. - let place = self.make_place(local, projection).unwrap(); + // We know that the projection only contains trackable elements. + let place = self.make_place(local, projection).unwrap(); - // Allocate a value slot if it doesn't have one. - if self.places[place].value_index.is_none() { - self.places[place].value_index = Some(self.value_count.into()); - self.value_count += 1; + // Allocate a value slot if it doesn't have one, and the user requested one. + if self.places[place].value_index.is_none() && filter(ty) { + self.places[place].value_index = Some(self.value_count.into()); + self.value_count += 1; + } + + if ty.is_enum() { + let discr_ty = ty.discriminant_ty(tcx); + if filter(discr_ty) { + let discr = *self + .projections + .entry((place, TrackElem::Discriminant)) + .or_insert_with(|| { + // Prepend new child to the linked list. + let next = self.places.push(PlaceInfo::new(Some(TrackElem::Discriminant))); + self.places[next].next_sibling = self.places[place].first_child; + self.places[place].first_child = Some(next); + next + }); + + // Allocate a value slot if it doesn't have one. + if self.places[discr].value_index.is_none() { + self.places[discr].value_index = Some(self.value_count.into()); + self.value_count += 1; + } } } // Recurse with all fields of this place. iter_fields(ty, tcx, |variant, field, ty| { - if variant.is_some() { - // Downcasts are currently not supported. + if let Some(variant) = variant { + projection.push(PlaceElem::Downcast(None, variant)); + let _ = self.make_place(local, projection); + projection.push(PlaceElem::Field(field, ty)); + self.register_with_filter_rec(tcx, local, projection, ty, filter); + projection.pop(); + projection.pop(); return; } projection.push(PlaceElem::Field(field, ty)); @@ -694,13 +731,77 @@ impl Map { Some(index) } + /// Locates the given place, if it exists in the tree. + pub fn find_discr(&self, place: PlaceRef<'_>) -> Option<PlaceIndex> { + let index = self.find(place)?; + self.apply(index, TrackElem::Discriminant) + } + /// Iterate over all direct children. pub fn children(&self, parent: PlaceIndex) -> impl Iterator<Item = PlaceIndex> + '_ { Children::new(self, parent) } + /// Invoke a function on the given place and all places that may alias it. + /// + /// In particular, when the given place has a variant downcast, we invoke the function on all + /// the other variants. + /// + /// `tail_elem` allows to support discriminants that are not a place in MIR, but that we track + /// as such. + fn for_each_aliasing_place( + &self, + place: PlaceRef<'_>, + tail_elem: Option<TrackElem>, + f: &mut impl FnMut(PlaceIndex), + ) { + let Some(&Some(mut index)) = self.locals.get(place.local) else { + // The local is not tracked at all, nothing to invalidate. + return; + }; + let elems = place + .projection + .iter() + .map(|&elem| elem.try_into()) + .chain(tail_elem.map(Ok).into_iter()); + for elem in elems { + let Ok(elem) = elem else { return }; + let sub = self.apply(index, elem); + if let TrackElem::Variant(..) | TrackElem::Discriminant = elem { + // Writing to an enum variant field invalidates the other variants and the discriminant. + self.for_each_variant_sibling(index, sub, f); + } + if let Some(sub) = sub { + index = sub + } else { + return; + } + } + self.preorder_invoke(index, f); + } + + /// Invoke the given function on all the descendants of the given place, except one branch. + pub fn for_each_variant_sibling( + &self, + parent: PlaceIndex, + preserved_child: Option<PlaceIndex>, + f: &mut impl FnMut(PlaceIndex), + ) { + for sibling in self.children(parent) { + let elem = self.places[sibling].proj_elem; + // Only invalidate variants and discriminant. Fields (for generators) are not + // invalidated by assignment to a variant. + if let Some(TrackElem::Variant(..) | TrackElem::Discriminant) = elem + // Only invalidate the other variants, the current one is fine. + && Some(sibling) != preserved_child + { + self.preorder_invoke(sibling, f); + } + } + } + /// Invoke a function on the given place and all descendants. - pub fn preorder_invoke(&self, root: PlaceIndex, f: &mut impl FnMut(PlaceIndex)) { + fn preorder_invoke(&self, root: PlaceIndex, f: &mut impl FnMut(PlaceIndex)) { f(root); for child in self.children(root) { self.preorder_invoke(child, f); @@ -759,6 +860,7 @@ impl<'a> Iterator for Children<'a> { } /// Used as the result of an operand or r-value. +#[derive(Debug)] pub enum ValueOrPlace<V> { Value(V), Place(PlaceIndex), @@ -776,6 +878,8 @@ impl<V: HasTop> ValueOrPlace<V> { #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)] pub enum TrackElem { Field(Field), + Variant(VariantIdx), + Discriminant, } impl<V, T> TryFrom<ProjectionElem<V, T>> for TrackElem { @@ -784,6 +888,7 @@ impl<V, T> TryFrom<ProjectionElem<V, T>> for TrackElem { fn try_from(value: ProjectionElem<V, T>) -> Result<Self, Self::Error> { match value { ProjectionElem::Field(field, _) => Ok(TrackElem::Field(field)), + ProjectionElem::Downcast(_, idx) => Ok(TrackElem::Variant(idx)), _ => Err(()), } } @@ -900,6 +1005,12 @@ fn debug_with_context_rec<V: Debug + Eq>( for child in map.children(place) { let info_elem = map.places[child].proj_elem.unwrap(); let child_place_str = match info_elem { + TrackElem::Discriminant => { + format!("discriminant({})", place_str) + } + TrackElem::Variant(idx) => { + format!("({} as {:?})", place_str, idx) + } TrackElem::Field(field) => { if place_str.starts_with('*') { format!("({}).{}", place_str, field.index()) diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs index 949a59a97bf..f10f208f5de 100644 --- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs +++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs @@ -13,6 +13,7 @@ use rustc_mir_dataflow::value_analysis::{Map, State, TrackElem, ValueAnalysis, V use rustc_mir_dataflow::{lattice::FlatSet, Analysis, ResultsVisitor, SwitchIntEdgeEffects}; use rustc_span::DUMMY_SP; use rustc_target::abi::Align; +use rustc_target::abi::VariantIdx; use crate::MirPass; @@ -30,6 +31,7 @@ impl<'tcx> MirPass<'tcx> for DataflowConstProp { #[instrument(skip_all level = "debug")] fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { + debug!(def_id = ?body.source.def_id()); if tcx.sess.mir_opt_level() < 4 && body.basic_blocks.len() > BLOCK_LIMIT { debug!("aborted dataflow const prop due too many basic blocks"); return; @@ -63,14 +65,31 @@ impl<'tcx> MirPass<'tcx> for DataflowConstProp { } } -struct ConstAnalysis<'tcx> { +struct ConstAnalysis<'a, 'tcx> { map: Map, tcx: TyCtxt<'tcx>, + local_decls: &'a LocalDecls<'tcx>, ecx: InterpCx<'tcx, 'tcx, DummyMachine>, param_env: ty::ParamEnv<'tcx>, } -impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> { +impl<'tcx> ConstAnalysis<'_, 'tcx> { + fn eval_disciminant( + &self, + enum_ty: Ty<'tcx>, + variant_index: VariantIdx, + ) -> Option<ScalarTy<'tcx>> { + if !enum_ty.is_enum() { + return None; + } + let discr = enum_ty.discriminant_for_variant(self.tcx, variant_index)?; + let discr_layout = self.tcx.layout_of(self.param_env.and(discr.ty)).ok()?; + let discr_value = Scalar::try_from_uint(discr.val, discr_layout.size)?; + Some(ScalarTy(discr_value, discr.ty)) + } +} + +impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'_, 'tcx> { type Value = FlatSet<ScalarTy<'tcx>>; const NAME: &'static str = "ConstAnalysis"; @@ -79,6 +98,25 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> { &self.map } + fn handle_statement(&self, statement: &Statement<'tcx>, state: &mut State<Self::Value>) { + match statement.kind { + StatementKind::SetDiscriminant { box ref place, variant_index } => { + state.flood_discr(place.as_ref(), &self.map); + if self.map.find_discr(place.as_ref()).is_some() { + let enum_ty = place.ty(self.local_decls, self.tcx).ty; + if let Some(discr) = self.eval_disciminant(enum_ty, variant_index) { + state.assign_discr( + place.as_ref(), + ValueOrPlace::Value(FlatSet::Elem(discr)), + &self.map, + ); + } + } + } + _ => self.super_statement(statement, state), + } + } + fn handle_assign( &self, target: Place<'tcx>, @@ -87,17 +125,22 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> { ) { match rvalue { Rvalue::Aggregate(kind, operands) => { - let target = self.map().find(target.as_ref()); - if let Some(target) = target { - state.flood_idx_with(target, self.map(), FlatSet::Bottom); - let field_based = match **kind { - AggregateKind::Tuple | AggregateKind::Closure(..) => true, - AggregateKind::Adt(def_id, ..) => { - matches!(self.tcx.def_kind(def_id), DefKind::Struct) + state.flood_with(target.as_ref(), self.map(), FlatSet::Bottom); + if let Some(target_idx) = self.map().find(target.as_ref()) { + let (variant_target, variant_index) = match **kind { + AggregateKind::Tuple | AggregateKind::Closure(..) => { + (Some(target_idx), None) + } + AggregateKind::Adt(def_id, variant_index, ..) => { + match self.tcx.def_kind(def_id) { + DefKind::Struct => (Some(target_idx), None), + DefKind::Enum => (Some(target_idx), Some(variant_index)), + _ => (None, None), + } } - _ => false, + _ => (None, None), }; - if field_based { + if let Some(target) = variant_target { for (field_index, operand) in operands.iter().enumerate() { if let Some(field) = self .map() @@ -108,15 +151,20 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> { } } } + if let Some(variant_index) = variant_index + && let Some(discr_idx) = self.map().apply(target_idx, TrackElem::Discriminant) + { + let enum_ty = target.ty(self.local_decls, self.tcx).ty; + if let Some(discr_val) = self.eval_disciminant(enum_ty, variant_index) { + state.assign_idx(discr_idx, ValueOrPlace::Value(FlatSet::Elem(discr_val)), &self.map); + } + } } } Rvalue::CheckedBinaryOp(op, box (left, right)) => { + state.flood(target.as_ref(), self.map()); + let target = self.map().find(target.as_ref()); - if let Some(target) = target { - // We should not track any projections other than - // what is overwritten below, but just in case... - state.flood_idx(target, self.map()); - } let value_target = target .and_then(|target| self.map().apply(target, TrackElem::Field(0_u32.into()))); @@ -195,6 +243,9 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'tcx> { FlatSet::Bottom => ValueOrPlace::Value(FlatSet::Bottom), FlatSet::Top => ValueOrPlace::Value(FlatSet::Top), }, + Rvalue::Discriminant(place) => { + ValueOrPlace::Value(state.get_discr(place.as_ref(), self.map())) + } _ => self.super_rvalue(rvalue, state), } } @@ -268,12 +319,13 @@ impl<'tcx> std::fmt::Debug for ScalarTy<'tcx> { } } -impl<'tcx> ConstAnalysis<'tcx> { - pub fn new(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, map: Map) -> Self { +impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> { + pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, map: Map) -> Self { let param_env = tcx.param_env(body.source.def_id()); Self { map, tcx, + local_decls: &body.local_decls, ecx: InterpCx::new(tcx, DUMMY_SP, param_env, DummyMachine), param_env: param_env, } @@ -466,6 +518,21 @@ impl<'tcx, 'map, 'a> Visitor<'tcx> for OperandCollector<'tcx, 'map, 'a> { _ => (), } } + + fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location) { + match rvalue { + Rvalue::Discriminant(place) => { + match self.state.get_discr(place.as_ref(), self.visitor.map) { + FlatSet::Top => (), + FlatSet::Elem(value) => { + self.visitor.before_effect.insert((location, *place), value); + } + FlatSet::Bottom => (), + } + } + _ => self.super_rvalue(rvalue, location), + } + } } struct DummyMachine; diff --git a/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff new file mode 100644 index 00000000000..038e6c6bd90 --- /dev/null +++ b/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff @@ -0,0 +1,26 @@ +- // MIR for `mutate_discriminant` before DataflowConstProp ++ // MIR for `mutate_discriminant` after DataflowConstProp + + fn mutate_discriminant() -> u8 { + let mut _0: u8; // return place in scope 0 at $DIR/enum.rs:+0:29: +0:31 + let mut _1: std::option::Option<NonZeroUsize>; // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL + let mut _2: isize; // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL + + bb0: { + discriminant(_1) = 1; // scope 0 at $DIR/enum.rs:+4:13: +4:34 + (((_1 as variant#1).0: NonZeroUsize).0: usize) = const 0_usize; // scope 0 at $DIR/enum.rs:+6:13: +6:64 + _2 = discriminant(_1); // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL + switchInt(_2) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/enum.rs:+9:13: +12:14 + } + + bb1: { + _0 = const 1_u8; // scope 0 at $DIR/enum.rs:+15:13: +15:20 + return; // scope 0 at $DIR/enum.rs:+16:13: +16:21 + } + + bb2: { + _0 = const 2_u8; // scope 0 at $DIR/enum.rs:+19:13: +19:20 + unreachable; // scope 0 at $DIR/enum.rs:+20:13: +20:26 + } + } + diff --git a/tests/mir-opt/dataflow-const-prop/enum.rs b/tests/mir-opt/dataflow-const-prop/enum.rs index 13288577dea..7ea405bd9c4 100644 --- a/tests/mir-opt/dataflow-const-prop/enum.rs +++ b/tests/mir-opt/dataflow-const-prop/enum.rs @@ -1,13 +1,52 @@ // unit-test: DataflowConstProp -// Not trackable, because variants could be aliased. +#![feature(custom_mir, core_intrinsics, rustc_attrs)] + +use std::intrinsics::mir::*; + enum E { V1(i32), V2(i32) } -// EMIT_MIR enum.main.DataflowConstProp.diff -fn main() { +// EMIT_MIR enum.simple.DataflowConstProp.diff +fn simple() { let e = E::V1(0); let x = match e { E::V1(x) => x, E::V2(x) => x }; } + +#[rustc_layout_scalar_valid_range_start(1)] +#[rustc_nonnull_optimization_guaranteed] +struct NonZeroUsize(usize); + +// EMIT_MIR enum.mutate_discriminant.DataflowConstProp.diff +#[custom_mir(dialect = "runtime", phase = "post-cleanup")] +fn mutate_discriminant() -> u8 { + mir!( + let x: Option<NonZeroUsize>; + { + SetDiscriminant(x, 1); + // This assignment overwrites the niche in which the discriminant is stored. + place!(Field(Field(Variant(x, 1), 0), 0)) = 0_usize; + // So we cannot know the value of this discriminant. + let a = Discriminant(x); + match a { + 0 => bb1, + _ => bad, + } + } + bb1 = { + RET = 1; + Return() + } + bad = { + RET = 2; + Unreachable() + } + ) +} + +fn main() { + simple(); + mutate_discriminant(); +} diff --git a/tests/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/enum.simple.DataflowConstProp.diff index d049c79d78d..1fb65e65845 100644 --- a/tests/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff +++ b/tests/mir-opt/dataflow-const-prop/enum.simple.DataflowConstProp.diff @@ -1,8 +1,8 @@ -- // MIR for `main` before DataflowConstProp -+ // MIR for `main` after DataflowConstProp +- // MIR for `simple` before DataflowConstProp ++ // MIR for `simple` after DataflowConstProp - fn main() -> () { - let mut _0: (); // return place in scope 0 at $DIR/enum.rs:+0:11: +0:11 + fn simple() -> () { + let mut _0: (); // return place in scope 0 at $DIR/enum.rs:+0:13: +0:13 let _1: E; // in scope 0 at $DIR/enum.rs:+1:9: +1:10 let mut _3: isize; // in scope 0 at $DIR/enum.rs:+2:23: +2:31 scope 1 { @@ -25,8 +25,10 @@ StorageLive(_1); // scope 0 at $DIR/enum.rs:+1:9: +1:10 _1 = E::V1(const 0_i32); // scope 0 at $DIR/enum.rs:+1:13: +1:21 StorageLive(_2); // scope 1 at $DIR/enum.rs:+2:9: +2:10 - _3 = discriminant(_1); // scope 1 at $DIR/enum.rs:+2:19: +2:20 - switchInt(move _3) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20 +- _3 = discriminant(_1); // scope 1 at $DIR/enum.rs:+2:19: +2:20 +- switchInt(move _3) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20 ++ _3 = const 0_isize; // scope 1 at $DIR/enum.rs:+2:19: +2:20 ++ switchInt(const 0_isize) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20 } bb1: { @@ -50,7 +52,7 @@ } bb4: { - _0 = const (); // scope 0 at $DIR/enum.rs:+0:11: +3:2 + _0 = const (); // scope 0 at $DIR/enum.rs:+0:13: +3:2 StorageDead(_2); // scope 1 at $DIR/enum.rs:+3:1: +3:2 StorageDead(_1); // scope 0 at $DIR/enum.rs:+3:1: +3:2 return; // scope 0 at $DIR/enum.rs:+3:2: +3:2 |