diff --git a/compiler/rustc_mir_dataflow/src/impls/liveness.rs b/compiler/rustc_mir_dataflow/src/impls/liveness.rs
index 6ec1b03a34e68..0db3435d489f5 100644
--- a/compiler/rustc_mir_dataflow/src/impls/liveness.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/liveness.rs
@@ -3,8 +3,9 @@ use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceC
use rustc_middle::mir::{
self, CallReturnPlaces, Local, Location, Place, StatementKind, TerminatorEdges,
};
+use rustc_middle::ty::TyCtxt;
-use crate::{Analysis, Backward, GenKill};
+use crate::{Analysis, Backward, GenKill, ResultsCursor};
/// A [live-variable dataflow analysis][liveness].
///
@@ -203,21 +204,42 @@ impl DefUse {
/// This is basically written for dead store elimination and nothing else.
///
/// All of the caveats of `MaybeLiveLocals` apply.
-pub struct MaybeTransitiveLiveLocals<'a> {
+pub struct MaybeTransitiveLiveLocals<'tcx, 'mir, 'a> {
always_live: &'a DenseBitSet<Local>,
+ live: Option<ResultsCursor<'mir, 'tcx, MaybeLiveLocals>>,
}
-impl<'a> MaybeTransitiveLiveLocals<'a> {
+impl<'tcx, 'mir, 'a> MaybeTransitiveLiveLocals<'tcx, 'mir, 'a> {
/// The `always_alive` set is the set of locals to which all stores should unconditionally be
/// considered live.
+ /// The `may_live_in_other_bbs` indicates that, when analyzing the current statement,
+ /// statements in other basic blocks are assumed to be live.
///
/// This should include at least all locals that are ever borrowed.
- pub fn new(always_live: &'a DenseBitSet<Local>) -> Self {
- MaybeTransitiveLiveLocals { always_live }
+ pub fn new(
+ always_live: &'a DenseBitSet<Local>,
+ may_live_in_other_bbs: bool,
+ tcx: TyCtxt<'tcx>,
+ body: &'mir mir::Body<'tcx>,
+ ) -> Self {
+ let live = if may_live_in_other_bbs {
+ Some(MaybeLiveLocals.iterate_to_fixpoint(tcx, body, None).into_results_cursor(body))
+ } else {
+ None
+ };
+ MaybeTransitiveLiveLocals { always_live, live }
+ }
+
+ fn live_on(&mut self, place: Place<'_>, location: Location) -> bool {
+ let Some(live) = &mut self.live else {
+ return false;
+ };
+ live.seek_before_primary_effect(location);
+ live.get().contains(place.local)
}
}
-impl<'a, 'tcx> Analysis<'tcx> for MaybeTransitiveLiveLocals<'a> {
+impl<'a, 'tcx> Analysis<'tcx> for MaybeTransitiveLiveLocals<'tcx, '_, 'a> {
type Domain = DenseBitSet<Local>;
type Direction = Backward;
@@ -256,14 +278,14 @@ impl<'a, 'tcx> Analysis<'tcx> for MaybeTransitiveLiveLocals<'a> {
| StatementKind::BackwardIncompatibleDropHint { .. }
| StatementKind::Nop => None,
};
- if let Some(destination) = destination {
- if !destination.is_indirect()
- && !state.contains(destination.local)
- && !self.always_live.contains(destination.local)
- {
- // This store is dead
- return;
- }
+ if let Some(destination) = destination
+ && !destination.is_indirect()
+ && !state.contains(destination.local)
+ && !self.always_live.contains(destination.local)
+ && !self.live_on(destination, location)
+ {
+ // This store is dead
+ return;
}
TransferFunction(state).visit_statement(statement, location);
}
diff --git a/compiler/rustc_mir_transform/src/dead_store_elimination.rs b/compiler/rustc_mir_transform/src/dead_store_elimination.rs
index eea2b0990d730..69234bbc60813 100644
--- a/compiler/rustc_mir_transform/src/dead_store_elimination.rs
+++ b/compiler/rustc_mir_transform/src/dead_store_elimination.rs
@@ -12,6 +12,7 @@
//! will still not cause any further changes.
//!
+use rustc_index::IndexVec;
use rustc_middle::bug;
use rustc_middle::mir::visit::Visitor;
use rustc_middle::mir::*;
@@ -24,19 +25,52 @@ use rustc_mir_dataflow::impls::{
use crate::util::is_within_packed;
+pub(super) enum ModifyBasicBlocks<'tcx, 'a> {
+ Direct(&'a mut Body<'tcx>),
+ BasicBlocks(&'a Body<'tcx>, &'a mut IndexVec<BasicBlock, BasicBlockData<'tcx>>),
+}
+
+impl<'tcx, 'a> ModifyBasicBlocks<'tcx, 'a> {
+ pub(super) fn body(&self) -> &Body<'tcx> {
+ match self {
+ ModifyBasicBlocks::Direct(body) => body,
+ ModifyBasicBlocks::BasicBlocks(body, _) => body,
+ }
+ }
+
+ pub(super) fn bbs(&mut self) -> &mut IndexVec<BasicBlock, BasicBlockData<'tcx>> {
+ match self {
+ ModifyBasicBlocks::Direct(body) => body.basic_blocks.as_mut_preserves_cfg(),
+ ModifyBasicBlocks::BasicBlocks(_, bbs) => bbs,
+ }
+ }
+}
+
/// Performs the optimization on the body
///
/// The `borrowed` set must be a `DenseBitSet` of all the locals that are ever borrowed in this
/// body. It can be generated via the [`borrowed_locals`] function.
-fn eliminate<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+pub(super) fn eliminate<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ mut modify_basic_blocks: ModifyBasicBlocks<'tcx, '_>,
+ ignore_debuginfo: bool,
+ arg_copy_to_move: bool,
+ may_live_in_other_bbs: bool,
+) {
+ let body = modify_basic_blocks.body();
let borrowed_locals = borrowed_locals(body);
// If the user requests complete debuginfo, mark the locals that appear in it as live, so
// we don't remove assignments to them.
- let mut always_live = debuginfo_locals(body);
- always_live.union(&borrowed_locals);
-
- let mut live = MaybeTransitiveLiveLocals::new(&always_live)
+ let always_live = if ignore_debuginfo {
+ borrowed_locals.clone()
+ } else {
+ let mut always_live = debuginfo_locals(body);
+ always_live.union(&borrowed_locals);
+ always_live
+ };
+
+ let mut live = MaybeTransitiveLiveLocals::new(&always_live, may_live_in_other_bbs, tcx, body)
.iterate_to_fixpoint(tcx, body, None)
.into_results_cursor(body);
@@ -46,7 +80,8 @@ fn eliminate<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
let mut patch = Vec::new();
for (bb, bb_data) in traversal::preorder(body) {
- if let TerminatorKind::Call { ref args, .. } = bb_data.terminator().kind {
+ if arg_copy_to_move && let TerminatorKind::Call { ref args, .. } = bb_data.terminator().kind
+ {
let loc = Location { block: bb, statement_index: bb_data.statements.len() };
// Position ourselves between the evaluation of `args` and the write to `destination`.
@@ -113,7 +148,7 @@ fn eliminate<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
return;
}
- let bbs = body.basic_blocks.as_mut_preserves_cfg();
+ let bbs = modify_basic_blocks.bbs();
for Location { block, statement_index } in patch {
bbs[block].statements[statement_index].make_nop();
}
@@ -145,7 +180,7 @@ impl<'tcx> crate::MirPass<'tcx> for DeadStoreElimination {
}
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
- eliminate(tcx, body);
+ eliminate(tcx, ModifyBasicBlocks::Direct(body), false, true, false);
}
fn is_required(&self) -> bool {
diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs
index dfd07f0fb1681..0de8af3e2a4a3 100644
--- a/compiler/rustc_mir_transform/src/lib.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@@ -700,8 +700,6 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
// Now, we need to shrink the generated MIR.
&ref_prop::ReferencePropagation,
&sroa::ScalarReplacementOfAggregates,
- &match_branches::MatchBranchSimplification,
- // inst combine is after MatchBranchSimplification to clean up Ne(_1, false)
&multiple_return_terminators::MultipleReturnTerminators,
// After simplifycfg, it allows us to discover new opportunities for peephole
// optimizations.
@@ -710,6 +708,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
&dead_store_elimination::DeadStoreElimination::Initial,
&gvn::GVN,
&simplify::SimplifyLocals::AfterGVN,
+ &match_branches::MatchBranchSimplification,
&dataflow_const_prop::DataflowConstProp,
&single_use_consts::SingleUseConsts,
&o1(simplify_branches::SimplifyConstCondition::AfterConstProp),
diff --git a/compiler/rustc_mir_transform/src/match_branches.rs b/compiler/rustc_mir_transform/src/match_branches.rs
index 0d9d0368d3729..30cb0ff8348d8 100644
--- a/compiler/rustc_mir_transform/src/match_branches.rs
+++ b/compiler/rustc_mir_transform/src/match_branches.rs
@@ -1,14 +1,17 @@
use std::iter;
use rustc_abi::Integer;
-use rustc_index::IndexSlice;
+use rustc_index::{IndexSlice, IndexVec};
+use rustc_middle::mir::visit::Visitor;
use rustc_middle::mir::*;
use rustc_middle::ty::layout::{IntegerExt, TyAndLayout};
use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt};
use tracing::instrument;
use super::simplify::simplify_cfg;
+use crate::dead_store_elimination::{self, ModifyBasicBlocks};
use crate::patch::MirPatch;
+use crate::simplify::strip_nops;
pub(super) struct MatchBranchSimplification;
@@ -19,32 +22,50 @@ impl<'tcx> crate::MirPass<'tcx> for MatchBranchSimplification {
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
let typing_env = body.typing_env(tcx);
- let mut should_cleanup = false;
- for i in 0..body.basic_blocks.len() {
- let bbs = &*body.basic_blocks;
- let bb_idx = BasicBlock::from_usize(i);
- match bbs[bb_idx].terminator().kind {
+ let mut apply_patch = false;
+ let mut bbs = body.basic_blocks.clone();
+ let bbs = bbs.as_mut_preserves_cfg();
+ // We can ignore the dead store statements when merging branches.
+ dead_store_elimination::eliminate(
+ tcx,
+ ModifyBasicBlocks::BasicBlocks(body, bbs),
+ true,
+ false,
+ true,
+ );
+ eliminate_unused_storage_mark(body, bbs);
+ strip_nops(bbs.as_mut_slice());
+ let mut patch = MirPatch::new(body);
+ for (bb, data) in body.basic_blocks.iter_enumerated() {
+ match data.terminator().kind {
TerminatorKind::SwitchInt {
discr: ref _discr @ (Operand::Copy(_) | Operand::Move(_)),
ref targets,
..
// We require that the possible target blocks don't contain this block.
- } if !targets.all_targets().contains(&bb_idx) => {}
+ } if !targets.all_targets().contains(&bb) => {}
// Only optimize switch int statements
_ => continue,
};
- if SimplifyToIf.simplify(tcx, body, bb_idx, typing_env).is_some() {
- should_cleanup = true;
+ if SimplifyToIf
+ .simplify(tcx, body, bbs.as_slice(), &mut patch, bb, typing_env)
+ .is_some()
+ {
+ apply_patch = true;
continue;
}
- if SimplifyToExp::default().simplify(tcx, body, bb_idx, typing_env).is_some() {
- should_cleanup = true;
+ if SimplifyToExp::default()
+ .simplify(tcx, body, bbs.as_slice(), &mut patch, bb, typing_env)
+ .is_some()
+ {
+ apply_patch = true;
continue;
}
}
- if should_cleanup {
+ if apply_patch {
+ patch.apply(body);
simplify_cfg(body);
}
}
@@ -61,11 +82,12 @@ trait SimplifyMatch<'tcx> {
fn simplify(
&mut self,
tcx: TyCtxt<'tcx>,
- body: &mut Body<'tcx>,
+ body: &Body<'tcx>,
+ bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
+ patch: &mut MirPatch<'tcx>,
switch_bb_idx: BasicBlock,
typing_env: ty::TypingEnv<'tcx>,
) -> Option<()> {
- let bbs = &body.basic_blocks;
let (discr, targets) = match bbs[switch_bb_idx].terminator().kind {
TerminatorKind::SwitchInt { ref discr, ref targets, .. } => (discr, targets),
_ => unreachable!(),
@@ -74,8 +96,6 @@ trait SimplifyMatch<'tcx> {
let discr_ty = discr.ty(body.local_decls(), tcx);
self.can_simplify(tcx, targets, typing_env, bbs, discr_ty)?;
- let mut patch = MirPatch::new(body);
-
// Take ownership of items now that we know we can optimize.
let discr = discr.clone();
@@ -84,23 +104,13 @@ trait SimplifyMatch<'tcx> {
let discr_local = patch.new_temp(discr_ty, source_info.span);
let (_, first) = targets.iter().next().unwrap();
- let statement_index = bbs[switch_bb_idx].statements.len();
+ let statement_index = body.basic_blocks[switch_bb_idx].statements.len();
let parent_end = Location { block: switch_bb_idx, statement_index };
patch.add_statement(parent_end, StatementKind::StorageLive(discr_local));
patch.add_assign(parent_end, Place::from(discr_local), Rvalue::Use(discr));
- self.new_stmts(
- tcx,
- targets,
- typing_env,
- &mut patch,
- parent_end,
- bbs,
- discr_local,
- discr_ty,
- );
+ self.new_stmts(tcx, targets, typing_env, patch, parent_end, bbs, discr_local, discr_ty);
patch.add_statement(parent_end, StatementKind::StorageDead(discr_local));
patch.patch_terminator(switch_bb_idx, bbs[first].terminator().kind.clone());
- patch.apply(body);
Some(())
}
@@ -537,3 +547,43 @@ impl<'tcx> SimplifyMatch<'tcx> for SimplifyToExp {
}
}
}
+
+struct EliminateUnusedStorageMark {
+ storage_live_locals: IndexVec<Local, Option<usize>>,
+}
+
+impl<'tcx> Visitor<'tcx> for EliminateUnusedStorageMark {
+ fn visit_local(&mut self, local: Local, _: visit::PlaceContext, _: Location) {
+ self.storage_live_locals[local] = None;
+ }
+}
+
+fn eliminate_unused_storage_mark<'tcx>(
+ body: &Body<'tcx>,
+ basic_blocks: &mut IndexVec<BasicBlock, BasicBlockData<'tcx>>,
+) {
+ for (bb, data) in basic_blocks.iter_enumerated_mut() {
+ let mut unused_storage_mark = EliminateUnusedStorageMark {
+ storage_live_locals: IndexVec::from_elem_n(None, body.local_decls.len()),
+ };
+ for stmt_index in 0..data.statements.len() {
+ let loc = Location { block: bb, statement_index: stmt_index };
+ match data.statements[stmt_index].kind {
+ StatementKind::StorageLive(local) => {
+ unused_storage_mark.storage_live_locals[local] = Some(stmt_index);
+ }
+ StatementKind::StorageDead(local)
+ if let Some(live_stmt_index) =
+ unused_storage_mark.storage_live_locals[local] =>
+ {
+ data.statements[live_stmt_index].make_nop();
+ data.statements[stmt_index].make_nop();
+ unused_storage_mark.storage_live_locals[local] = None;
+ }
+ _ => {
+ unused_storage_mark.visit_statement(&data.statements[stmt_index], loc);
+ }
+ }
+ }
+ }
+}
diff --git a/compiler/rustc_mir_transform/src/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs
index 84905f4a400f3..92dfea4190d33 100644
--- a/compiler/rustc_mir_transform/src/simplify.rs
+++ b/compiler/rustc_mir_transform/src/simplify.rs
@@ -116,7 +116,7 @@ impl<'a, 'tcx> CfgSimplifier<'a, 'tcx> {
}
fn simplify(mut self) {
- self.strip_nops();
+ strip_nops(self.basic_blocks);
// Vec of the blocks that should be merged. We store the indices here, instead of the
// statements itself to avoid moving the (relatively) large statements twice.
@@ -276,11 +276,11 @@ impl<'a, 'tcx> CfgSimplifier<'a, 'tcx> {
terminator.kind = TerminatorKind::Goto { target: first_succ };
true
}
+}
- fn strip_nops(&mut self) {
- for blk in self.basic_blocks.iter_mut() {
- blk.statements.retain(|stmt| !matches!(stmt.kind, StatementKind::Nop))
- }
+pub(super) fn strip_nops(basic_blocks: &mut IndexSlice<BasicBlock, BasicBlockData<'_>>) {
+ for blk in basic_blocks.iter_mut() {
+ blk.statements.retain(|stmt| !matches!(stmt.kind, StatementKind::Nop))
}
}
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
index f36157a762c27..39ba480d20330 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-abort.diff
@@ -8,9 +8,9 @@
let mut _3: u16;
let mut _4: u32;
+ scope 1 (inlined core::num::<impl u16>::unchecked_shl) {
-+ let mut _5: bool;
-+ let _6: ();
++ let _5: ();
+ scope 2 (inlined core::ub_checks::check_language_ub) {
++ let mut _6: bool;
+ scope 3 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -22,20 +22,20 @@
StorageLive(_4);
_4 = copy _2;
- _0 = core::num::<impl u16>::unchecked_shl(move _3, move _4) -> [return: bb1, unwind unreachable];
-+ StorageLive(_6);
+ StorageLive(_5);
-+ _5 = UbChecks();
-+ switchInt(move _5) -> [0: bb2, otherwise: bb1];
++ StorageLive(_6);
++ _6 = UbChecks();
++ switchInt(copy _6) -> [0: bb2, otherwise: bb1];
}
bb1: {
-+ _6 = core::num::<impl u16>::unchecked_shl::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
++ _5 = core::num::<impl u16>::unchecked_shl::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
+ }
+
+ bb2: {
-+ StorageDead(_5);
+ _0 = ShlUnchecked(copy _3, copy _4);
+ StorageDead(_6);
++ StorageDead(_5);
StorageDead(_4);
StorageDead(_3);
return;
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
index be1b066c6c1b4..5a758d3574060 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shl_unsigned_smaller.Inline.panic-unwind.diff
@@ -8,9 +8,9 @@
let mut _3: u16;
let mut _4: u32;
+ scope 1 (inlined core::num::<impl u16>::unchecked_shl) {
-+ let mut _5: bool;
-+ let _6: ();
++ let _5: ();
+ scope 2 (inlined core::ub_checks::check_language_ub) {
++ let mut _6: bool;
+ scope 3 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -22,20 +22,20 @@
StorageLive(_4);
_4 = copy _2;
- _0 = core::num::<impl u16>::unchecked_shl(move _3, move _4) -> [return: bb1, unwind continue];
-+ StorageLive(_6);
+ StorageLive(_5);
-+ _5 = UbChecks();
-+ switchInt(move _5) -> [0: bb2, otherwise: bb1];
++ StorageLive(_6);
++ _6 = UbChecks();
++ switchInt(copy _6) -> [0: bb2, otherwise: bb1];
}
bb1: {
-+ _6 = core::num::<impl u16>::unchecked_shl::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
++ _5 = core::num::<impl u16>::unchecked_shl::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
+ }
+
+ bb2: {
-+ StorageDead(_5);
+ _0 = ShlUnchecked(copy _3, copy _4);
+ StorageDead(_6);
++ StorageDead(_5);
StorageDead(_4);
StorageDead(_3);
return;
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
index 360687f3c4e7f..a0caf141f2d06 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-abort.diff
@@ -8,9 +8,9 @@
let mut _3: i64;
let mut _4: u32;
+ scope 1 (inlined core::num::<impl i64>::unchecked_shr) {
-+ let mut _5: bool;
-+ let _6: ();
++ let _5: ();
+ scope 2 (inlined core::ub_checks::check_language_ub) {
++ let mut _6: bool;
+ scope 3 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -22,20 +22,20 @@
StorageLive(_4);
_4 = copy _2;
- _0 = core::num::<impl i64>::unchecked_shr(move _3, move _4) -> [return: bb1, unwind unreachable];
-+ StorageLive(_6);
+ StorageLive(_5);
-+ _5 = UbChecks();
-+ switchInt(move _5) -> [0: bb2, otherwise: bb1];
++ StorageLive(_6);
++ _6 = UbChecks();
++ switchInt(copy _6) -> [0: bb2, otherwise: bb1];
}
bb1: {
-+ _6 = core::num::<impl i64>::unchecked_shr::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
++ _5 = core::num::<impl i64>::unchecked_shr::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
+ }
+
+ bb2: {
-+ StorageDead(_5);
+ _0 = ShrUnchecked(copy _3, copy _4);
+ StorageDead(_6);
++ StorageDead(_5);
StorageDead(_4);
StorageDead(_3);
return;
diff --git a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
index 986df55df0372..633089e7b2a28 100644
--- a/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/unchecked_shifts.unchecked_shr_signed_bigger.Inline.panic-unwind.diff
@@ -8,9 +8,9 @@
let mut _3: i64;
let mut _4: u32;
+ scope 1 (inlined core::num::<impl i64>::unchecked_shr) {
-+ let mut _5: bool;
-+ let _6: ();
++ let _5: ();
+ scope 2 (inlined core::ub_checks::check_language_ub) {
++ let mut _6: bool;
+ scope 3 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -22,20 +22,20 @@
StorageLive(_4);
_4 = copy _2;
- _0 = core::num::<impl i64>::unchecked_shr(move _3, move _4) -> [return: bb1, unwind continue];
-+ StorageLive(_6);
+ StorageLive(_5);
-+ _5 = UbChecks();
-+ switchInt(move _5) -> [0: bb2, otherwise: bb1];
++ StorageLive(_6);
++ _6 = UbChecks();
++ switchInt(copy _6) -> [0: bb2, otherwise: bb1];
}
bb1: {
-+ _6 = core::num::<impl i64>::unchecked_shr::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
++ _5 = core::num::<impl i64>::unchecked_shr::precondition_check(copy _4) -> [return: bb2, unwind unreachable];
+ }
+
+ bb2: {
-+ StorageDead(_5);
+ _0 = ShrUnchecked(copy _3, copy _4);
+ StorageDead(_6);
++ StorageDead(_5);
StorageDead(_4);
StorageDead(_3);
return;
diff --git a/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-abort.diff b/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-abort.diff
index 28878736ed7cd..a5986a4315a2d 100644
--- a/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-abort.diff
@@ -10,9 +10,9 @@
+ scope 2 {
+ }
+ scope 3 (inlined unreachable_unchecked) {
-+ let mut _4: bool;
-+ let _5: ();
++ let _4: ();
+ scope 4 (inlined core::ub_checks::check_language_ub) {
++ let mut _5: bool;
+ scope 5 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -24,7 +24,7 @@
_2 = move _1;
- _0 = Option::<T>::unwrap_unchecked(move _2) -> [return: bb1, unwind unreachable];
+ StorageLive(_3);
-+ StorageLive(_5);
++ StorageLive(_4);
+ _3 = discriminant(_2);
+ switchInt(move _3) -> [0: bb2, 1: bb3, otherwise: bb1];
}
@@ -34,15 +34,15 @@
+ }
+
+ bb2: {
-+ StorageLive(_4);
-+ _4 = UbChecks();
-+ assume(copy _4);
-+ _5 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
++ StorageLive(_5);
++ _5 = UbChecks();
++ assume(copy _5);
++ _4 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
+ }
+
+ bb3: {
+ _0 = move ((_2 as Some).0: T);
-+ StorageDead(_5);
++ StorageDead(_4);
+ StorageDead(_3);
StorageDead(_2);
return;
diff --git a/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-unwind.diff b/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-unwind.diff
index 27b6bb6a5bb23..12b03a6b6d921 100644
--- a/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/unwrap_unchecked.unwrap_unchecked.Inline.panic-unwind.diff
@@ -10,9 +10,9 @@
+ scope 2 {
+ }
+ scope 3 (inlined unreachable_unchecked) {
-+ let mut _4: bool;
-+ let _5: ();
++ let _4: ();
+ scope 4 (inlined core::ub_checks::check_language_ub) {
++ let mut _5: bool;
+ scope 5 (inlined core::ub_checks::check_language_ub::runtime) {
+ }
+ }
@@ -24,7 +24,7 @@
_2 = move _1;
- _0 = Option::<T>::unwrap_unchecked(move _2) -> [return: bb1, unwind: bb2];
+ StorageLive(_3);
-+ StorageLive(_5);
++ StorageLive(_4);
+ _3 = discriminant(_2);
+ switchInt(move _3) -> [0: bb2, 1: bb3, otherwise: bb1];
}
@@ -38,15 +38,15 @@
- bb2 (cleanup): {
- resume;
+ bb2: {
-+ StorageLive(_4);
-+ _4 = UbChecks();
-+ assume(copy _4);
-+ _5 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
++ StorageLive(_5);
++ _5 = UbChecks();
++ assume(copy _5);
++ _4 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
+ }
+
+ bb3: {
+ _0 = move ((_2 as Some).0: T);
-+ StorageDead(_5);
++ StorageDead(_4);
+ StorageDead(_3);
+ StorageDead(_2);
+ return;
diff --git a/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff b/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
index 5fee9a6733dd0..82353a2d5404a 100644
--- a/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
@@ -10,9 +10,9 @@
scope 2 {
}
scope 3 (inlined unreachable_unchecked) {
- let mut _4: bool;
- let _5: ();
+ let _4: ();
scope 4 (inlined core::ub_checks::check_language_ub) {
+ let mut _5: bool;
scope 5 (inlined core::ub_checks::check_language_ub::runtime) {
}
}
@@ -23,7 +23,7 @@
StorageLive(_2);
_2 = copy _1;
StorageLive(_3);
- StorageLive(_5);
+ StorageLive(_4);
_3 = discriminant(_2);
switchInt(move _3) -> [0: bb2, 1: bb3, otherwise: bb1];
}
@@ -33,16 +33,16 @@
}
bb2: {
- StorageLive(_4);
-- _4 = UbChecks();
-+ _4 = const false;
- assume(copy _4);
- _5 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
+ StorageLive(_5);
+- _5 = UbChecks();
++ _5 = const false;
+ assume(copy _5);
+ _4 = unreachable_unchecked::precondition_check() -> [return: bb1, unwind unreachable];
}
bb3: {
_0 = move ((_2 as Some).0: i32);
- StorageDead(_5);
+ StorageDead(_4);
StorageDead(_3);
StorageDead(_2);
return;
diff --git a/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff b/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
index 1ab9be9665221..d8eace98d556e 100644
--- a/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
+++ b/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
@@ -5,23 +5,18 @@
debug bytes => _1;
let mut _0: std::option::Option<[u8; 4]>;
let _2: [u32; 4];
- let mut _3: [u8; 16];
- let mut _5: [u8; 4];
- let mut _6: u32;
+ let mut _4: [u8; 4];
scope 1 {
debug dwords => _2;
scope 2 {
- debug ip => _4;
- let _4: u32;
+ debug ip => _3;
+ let _3: u32;
}
}
bb0: {
StorageLive(_2);
- StorageLive(_3);
- _3 = copy _1;
- _2 = move _3 as [u32; 4] (Transmute);
- StorageDead(_3);
+ _2 = copy _1 as [u32; 4] (Transmute);
switchInt(copy _2[0 of 4]) -> [0: bb1, otherwise: bb4];
}
@@ -34,15 +29,10 @@
}
bb3: {
+ _3 = copy _2[3 of 4];
StorageLive(_4);
- _4 = copy _2[3 of 4];
- StorageLive(_5);
- StorageLive(_6);
- _6 = copy _4;
- _5 = move _6 as [u8; 4] (Transmute);
- StorageDead(_6);
- _0 = Option::<[u8; 4]>::Some(move _5);
- StorageDead(_5);
+ _4 = copy _3 as [u8; 4] (Transmute);
+ _0 = Option::<[u8; 4]>::Some(move _4);
StorageDead(_4);
goto -> bb5;
}
diff --git a/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
index 597d93926f169..69cdb451fa754 100644
--- a/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
@@ -45,7 +45,7 @@
+ _3 = Eq(copy _11, const 7_i32);
_4 = const false;
_5 = const true;
- _6 = ();
+- _6 = ();
- goto -> bb3;
- }
-
diff --git a/tests/mir-opt/matches_reduce_branches.match_dead_store_failed.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_dead_store_failed.MatchBranchSimplification.diff
new file mode 100644
index 0000000000000..7ae225c0d317a
--- /dev/null
+++ b/tests/mir-opt/matches_reduce_branches.match_dead_store_failed.MatchBranchSimplification.diff
@@ -0,0 +1,45 @@
+- // MIR for `match_dead_store_failed` before MatchBranchSimplification
++ // MIR for `match_dead_store_failed` after MatchBranchSimplification
+
+ fn match_dead_store_failed(_1: bool) -> () {
+ debug b => _1;
+ let mut _0: ();
+ let _2: (&str,);
+ let mut _3: &str;
+ let mut _4: bool;
+ let _5: &str;
+ scope 1 {
+ debug _b => _2;
+ }
+
+ bb0: {
+ StorageLive(_2);
+ StorageLive(_3);
+ StorageLive(_4);
+ _4 = copy _1;
+ switchInt(move _4) -> [0: bb2, otherwise: bb1];
+ }
+
+ bb1: {
+ _3 = const " ";
+ goto -> bb3;
+ }
+
+ bb2: {
+ StorageLive(_5);
+ _5 = const "";
+ _3 = &(*_5);
+ StorageDead(_5);
+ goto -> bb3;
+ }
+
+ bb3: {
+ StorageDead(_4);
+ _2 = (move _3,);
+ StorageDead(_3);
+ _0 = const ();
+ StorageDead(_2);
+ return;
+ }
+ }
+
diff --git a/tests/mir-opt/matches_reduce_branches.match_u8_i8_2.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_u8_i8_2.MatchBranchSimplification.diff
index f14b3af9660aa..d97cf629b1c4e 100644
--- a/tests/mir-opt/matches_reduce_branches.match_u8_i8_2.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.match_u8_i8_2.MatchBranchSimplification.diff
@@ -33,11 +33,7 @@
- bb2: {
- _2 = const -1_i8;
- _3 = const -1_i8;
-+ StorageLive(_8);
-+ _8 = move _5;
-+ _2 = copy _8 as i8 (IntToInt);
-+ _3 = copy _8 as i8 (IntToInt);
- _4 = ();
+- _4 = ();
- goto -> bb6;
- }
-
@@ -63,6 +59,10 @@
- }
-
- bb6: {
++ StorageLive(_8);
++ _8 = move _5;
++ _2 = copy _8 as i8 (IntToInt);
++ _3 = copy _8 as i8 (IntToInt);
+ StorageDead(_8);
StorageDead(_4);
StorageLive(_6);
diff --git a/tests/mir-opt/matches_reduce_branches.match_u8_i8_dead_store.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_u8_i8_dead_store.MatchBranchSimplification.diff
new file mode 100644
index 0000000000000..8874333c5893d
--- /dev/null
+++ b/tests/mir-opt/matches_reduce_branches.match_u8_i8_dead_store.MatchBranchSimplification.diff
@@ -0,0 +1,47 @@
+- // MIR for `match_u8_i8_dead_store` before MatchBranchSimplification
++ // MIR for `match_u8_i8_dead_store` after MatchBranchSimplification
+
+ fn match_u8_i8_dead_store(_1: EnumAu8) -> i8 {
+ let mut _0: i8;
+ let mut _2: u8;
++ let mut _3: u8;
+
+ bb0: {
+ _2 = discriminant(_1);
+- switchInt(copy _2) -> [0: bb1, 127: bb2, 128: bb3, 255: bb4, otherwise: bb5];
+- }
+-
+- bb1: {
+- _0 = const 0_i8;
+- goto -> bb6;
+- }
+-
+- bb2: {
+- _0 = const 1_i8;
+- _0 = const i8::MAX;
+- goto -> bb6;
+- }
+-
+- bb3: {
+- _0 = const i8::MIN;
+- goto -> bb6;
+- }
+-
+- bb4: {
+- _0 = const -1_i8;
+- goto -> bb6;
+- }
+-
+- bb5: {
+- unreachable;
+- }
+-
+- bb6: {
++ StorageLive(_3);
++ _3 = copy _2;
++ _0 = copy _3 as i8 (IntToInt);
++ StorageDead(_3);
+ return;
+ }
+ }
+
diff --git a/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_1.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_1.MatchBranchSimplification.diff
index a1d58424ecd1a..027ace9e4256e 100644
--- a/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_1.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_1.MatchBranchSimplification.diff
@@ -17,7 +17,7 @@
bb2: {
_0 = const i8::MAX;
- _0 = const i8::MAX;
+ _0 = Add(copy _0, const 0_i8);
goto -> bb6;
}
diff --git a/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_2.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_2.MatchBranchSimplification.diff
index 6c4ade1b6ca96..e97704df48743 100644
--- a/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_2.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.match_u8_i8_failed_len_2.MatchBranchSimplification.diff
@@ -27,7 +27,7 @@
bb4: {
_0 = const -1_i8;
- _0 = const -1_i8;
+ _0 = Add(copy _0, const 0_i8);
goto -> bb6;
}
diff --git a/tests/mir-opt/matches_reduce_branches.rs b/tests/mir-opt/matches_reduce_branches.rs
index 3372ae2f2a614..40d1d8e491003 100644
--- a/tests/mir-opt/matches_reduce_branches.rs
+++ b/tests/mir-opt/matches_reduce_branches.rs
@@ -237,7 +237,7 @@ fn match_u8_i8_failed_len_1(i: EnumAu8) -> i8 {
}
bb2 = {
RET = 127;
- RET = 127;
+ RET = RET + 0;
Goto(ret)
}
bb3 = {
@@ -289,6 +289,50 @@ fn match_u8_i8_failed_len_2(i: EnumAu8) -> i8 {
}
bb4 = {
RET = -1;
+ RET = RET + 0;
+ Goto(ret)
+ }
+ unreachable_bb = {
+ Unreachable()
+ }
+ ret = {
+ Return()
+ }
+ }
+}
+
+// EMIT_MIR matches_reduce_branches.match_u8_i8_dead_store.MatchBranchSimplification.diff
+#[custom_mir(dialect = "built")]
+fn match_u8_i8_dead_store(i: EnumAu8) -> i8 {
+ // CHECK-LABEL: fn match_u8_i8_dead_store(
+ // CHECK-NOT: switchInt
+ // CHECK: IntToInt
+ // CHECK: return
+ mir! {
+ {
+ let a = Discriminant(i);
+ match a {
+ 0 => bb1,
+ 127 => bb2,
+ 128 => bb3,
+ 255 => bb4,
+ _ => unreachable_bb,
+ }
+ }
+ bb1 = {
+ RET = 0;
+ Goto(ret)
+ }
+ bb2 = {
+ RET = 1; // This a dead store statement.
+ RET = 127;
+ Goto(ret)
+ }
+ bb3 = {
+ RET = -128;
+ Goto(ret)
+ }
+ bb4 = {
RET = -1;
Goto(ret)
}
@@ -628,6 +672,15 @@ fn match_i128_u128(i: EnumAi128) -> u128 {
}
}
+// We cannot merge these branches unless all the dead statements are eliminated.
+// EMIT_MIR matches_reduce_branches.match_dead_store_failed.MatchBranchSimplification.diff
+pub fn match_dead_store_failed(b: bool) {
+ // CHECK-LABEL: fn match_dead_store_failed(
+ // CHECK: switchInt
+ // CHECK: return
+ let _b = (if b { " " } else { "" },);
+}
+
fn main() {
let _ = foo(None);
let _ = foo(Some(()));
diff --git a/tests/mir-opt/pre-codegen/clone_as_copy.enum_clone_as_copy.PreCodegen.after.mir b/tests/mir-opt/pre-codegen/clone_as_copy.enum_clone_as_copy.PreCodegen.after.mir
index 9f88e1961ec88..b36475008efa9 100644
--- a/tests/mir-opt/pre-codegen/clone_as_copy.enum_clone_as_copy.PreCodegen.after.mir
+++ b/tests/mir-opt/pre-codegen/clone_as_copy.enum_clone_as_copy.PreCodegen.after.mir
@@ -5,11 +5,12 @@ fn enum_clone_as_copy(_1: &Enum1) -> Enum1 {
let mut _0: Enum1;
scope 1 (inlined <Enum1 as Clone>::clone) {
debug self => _1;
- let mut _2: isize;
+ let _2: &AllCopy;
let mut _3: &AllCopy;
- let mut _4: &NestCopy;
+ let _4: &NestCopy;
+ let mut _5: &NestCopy;
scope 2 {
- debug __self_0 => _3;
+ debug __self_0 => _2;
scope 6 (inlined <AllCopy as Clone>::clone) {
debug self => _3;
}
@@ -17,10 +18,10 @@ fn enum_clone_as_copy(_1: &Enum1) -> Enum1 {
scope 3 {
debug __self_0 => _4;
scope 4 (inlined <NestCopy as Clone>::clone) {
- debug self => _4;
- let _5: &AllCopy;
+ debug self => _5;
+ let _6: &AllCopy;
scope 5 (inlined <AllCopy as Clone>::clone) {
- debug self => _5;
+ debug self => _6;
}
}
}
@@ -30,33 +31,14 @@ fn enum_clone_as_copy(_1: &Enum1) -> Enum1 {
StorageLive(_2);
StorageLive(_3);
StorageLive(_4);
- _2 = discriminant((*_1));
- switchInt(move _2) -> [0: bb1, 1: bb2, otherwise: bb4];
- }
-
- bb1: {
- _3 = &(((*_1) as A).0: AllCopy);
- _0 = copy (*_1);
- goto -> bb3;
- }
-
- bb2: {
- _4 = &(((*_1) as B).0: NestCopy);
StorageLive(_5);
- _5 = &((((*_1) as B).0: NestCopy).1: AllCopy);
- StorageDead(_5);
+ StorageLive(_6);
_0 = copy (*_1);
- goto -> bb3;
- }
-
- bb3: {
+ StorageDead(_6);
+ StorageDead(_5);
StorageDead(_4);
StorageDead(_3);
StorageDead(_2);
return;
}
-
- bb4: {
- unreachable;
- }
}
diff --git a/tests/mir-opt/pre-codegen/clone_as_copy.rs b/tests/mir-opt/pre-codegen/clone_as_copy.rs
index f5ff1854d387d..c5ab43002560c 100644
--- a/tests/mir-opt/pre-codegen/clone_as_copy.rs
+++ b/tests/mir-opt/pre-codegen/clone_as_copy.rs
@@ -32,12 +32,12 @@ fn clone_as_copy(v: &NestCopy) -> NestCopy {
v.clone()
}
-// FIXME: We can merge into exactly one assignment statement.
+// We can merge into exactly one assignment statement.
// EMIT_MIR clone_as_copy.enum_clone_as_copy.PreCodegen.after.mir
fn enum_clone_as_copy(v: &Enum1) -> Enum1 {
// CHECK-LABEL: fn enum_clone_as_copy(
// CHECK-NOT: = Enum1::
// CHECK: _0 = copy (*_1);
- // CHECK: _0 = copy (*_1);
+ // CHECK-NOT: _0 = copy (*_1);
v.clone()
}
diff --git a/tests/mir-opt/pre-codegen/try_identity.old.PreCodegen.after.mir b/tests/mir-opt/pre-codegen/try_identity.old.PreCodegen.after.mir
index 889e80d26e1cc..f7b6cbc855f59 100644
--- a/tests/mir-opt/pre-codegen/try_identity.old.PreCodegen.after.mir
+++ b/tests/mir-opt/pre-codegen/try_identity.old.PreCodegen.after.mir
@@ -3,38 +3,17 @@
fn old(_1: Result<T, E>) -> Result<T, E> {
debug x => _1;
let mut _0: std::result::Result<T, E>;
- let mut _2: isize;
- let _3: T;
- let _4: E;
+ let _2: T;
+ let _3: E;
scope 1 {
- debug v => _3;
+ debug v => _2;
}
scope 2 {
- debug e => _4;
+ debug e => _3;
}
bb0: {
- _2 = discriminant(_1);
- switchInt(move _2) -> [0: bb1, 1: bb2, otherwise: bb4];
- }
-
- bb1: {
- _3 = copy ((_1 as Ok).0: T);
- _0 = copy _1;
- goto -> bb3;
- }
-
- bb2: {
- _4 = copy ((_1 as Err).0: E);
_0 = copy _1;
- goto -> bb3;
- }
-
- bb3: {
return;
}
-
- bb4: {
- unreachable;
- }
}
diff --git a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-abort.diff b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-abort.diff
index c363dfcbf70bb..ff1bc58524bc2 100644
--- a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-abort.diff
+++ b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-abort.diff
@@ -8,6 +8,9 @@
let mut _3: std::option::Option<T>;
let mut _4: isize;
let mut _5: isize;
+- let mut _7: bool;
+- let mut _8: u8;
+- let mut _9: bool;
scope 1 {
debug a => _6;
let _6: u8;
@@ -32,9 +35,7 @@
}
bb2: {
- StorageLive(_6);
_6 = copy (((_1.0: std::option::Option<u8>) as Some).0: u8);
- StorageDead(_6);
goto -> bb3;
}
diff --git a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-unwind.diff b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-unwind.diff
index 895b0067d2e63..2c289c664754a 100644
--- a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-unwind.diff
+++ b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.panic-unwind.diff
@@ -8,6 +8,9 @@
let mut _3: std::option::Option<T>;
let mut _4: isize;
let mut _5: isize;
+- let mut _7: bool;
+- let mut _8: u8;
+- let mut _9: bool;
scope 1 {
debug a => _6;
let _6: u8;
@@ -32,9 +35,7 @@
}
bb2: {
- StorageLive(_6);
_6 = copy (((_1.0: std::option::Option<u8>) as Some).0: u8);
- StorageDead(_6);
goto -> bb3;
}