Implement SSA CopyProp pass.

compiler/rustc_mir_transform/src/copy_prop.rs

@@ -0,0 +1,267 @@
+use either::Either;
+use rustc_index::bit_set::BitSet;
+use rustc_index::vec::IndexVec;
+use rustc_middle::middle::resolve_lifetime::Set1;
+use rustc_middle::mir::visit::*;
+use rustc_middle::mir::*;
+use rustc_middle::ty::{ParamEnv, TyCtxt};
+use rustc_mir_dataflow::impls::borrowed_locals;
+
+use crate::MirPass;
+
+/// Unify locals that copy each other.
+///
+/// We consider patterns of the form
+///   _a = rvalue
+///   _b = move? _a
+///   _c = move? _a
+///   _d = move? _c
+/// where each of the locals is only assigned once.
+///
+/// We want to replace all those locals by `_a`, either copied or moved.
+pub struct CopyProp;
+
+impl<'tcx> MirPass<'tcx> for CopyProp {
+    fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
+        sess.mir_opt_level() >= 4
+    }
+
+    #[instrument(level = "trace", skip(self, tcx, body))]
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+        debug!(def_id = ?body.source.def_id());
+        propagate_ssa(tcx, body);
+    }
+}
+
+fn propagate_ssa<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+    let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
+    let ssa = SsaLocals::new(tcx, param_env, body);
+
+    let (copy_classes, fully_moved) = compute_copy_classes(&ssa, body);
+    debug!(?copy_classes);
+
+    let mut storage_to_remove = BitSet::new_empty(fully_moved.domain_size());
+    for (local, &head) in copy_classes.iter_enumerated() {
+        if local != head {
+            storage_to_remove.insert(head);
+            storage_to_remove.insert(local);
+        }
+    }
+
+    let any_replacement = copy_classes.iter_enumerated().any(|(l, &h)| l != h);
+
+    Replacer { tcx, copy_classes, fully_moved, storage_to_remove }.visit_body_preserves_cfg(body);
+
+    if any_replacement {
+        crate::simplify::remove_unused_definitions(body);
+    }
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+enum LocationExtended {
+    Plain(Location),
+    Arg,
+}
+
+#[derive(Debug)]
+struct SsaLocals {
+    /// Assignments to each local.  This defines whether the local is SSA.
+    assignments: IndexVec<Local, Set1<LocationExtended>>,
+    /// We visit the body in reverse postorder, to ensure each local is assigned before it is used.
+    /// We remember the order in which we saw the assignments to compute the SSA values in a single
+    /// pass.
+    assignment_order: Vec<Local>,
+}
+
+impl SsaLocals {
+    fn new<'tcx>(tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, body: &Body<'tcx>) -> SsaLocals {
+        let assignment_order = Vec::new();
+
+        let assignments = IndexVec::from_elem(Set1::Empty, &body.local_decls);
+        let mut this = SsaLocals { assignments, assignment_order };
+
+        let borrowed = borrowed_locals(body);
+        for (local, decl) in body.local_decls.iter_enumerated() {
+            if matches!(body.local_kind(local), LocalKind::Arg) {
+                this.assignments[local] = Set1::One(LocationExtended::Arg);
+            }
+            if borrowed.contains(local) && !decl.ty.is_freeze(tcx, param_env) {
+                this.assignments[local] = Set1::Many;
+            }
+        }
+
+        for (bb, data) in traversal::reverse_postorder(body) {
+            this.visit_basic_block_data(bb, data);
+        }
+
+        for var_debug_info in &body.var_debug_info {
+            this.visit_var_debug_info(var_debug_info);
+        }
+
+        debug!(?this.assignments);
+
+        this.assignment_order.retain(|&local| matches!(this.assignments[local], Set1::One(_)));
+        debug!(?this.assignment_order);
+
+        this
+    }
+}
+
+impl<'tcx> Visitor<'tcx> for SsaLocals {
+    fn visit_local(&mut self, local: Local, ctxt: PlaceContext, loc: Location) {
+        match ctxt {
+            PlaceContext::MutatingUse(MutatingUseContext::Store) => {
+                self.assignments[local].insert(LocationExtended::Plain(loc));
+                self.assignment_order.push(local);
+            }
+            PlaceContext::MutatingUse(_) => self.assignments[local] = Set1::Many,
+            // Immutable borrows and AddressOf are taken into account in `SsaLocals::new` by
+            // removing non-freeze locals.
+            PlaceContext::NonMutatingUse(_) | PlaceContext::NonUse(_) => {}
+        }
+    }
+}
+
+/// Compute the equivalence classes for locals, based on copy statements.
+///
+/// The returned vector maps each local to the one it copies. In the following case:
+///   _a = &mut _0
+///   _b = move? _a
+///   _c = move? _a
+///   _d = move? _c
+/// We return the mapping
+///   _a => _a // not a copy so, represented by itself
+///   _b => _a
+///   _c => _a
+///   _d => _a // transitively through _c
+///
+/// This function also returns whether all the `move?` in the pattern are `move` and not copies.
+/// A local which is in the bitset can be replaced by `move _a`.  Otherwise, it must be
+/// replaced by `copy _a`, as we cannot move multiple times from `_a`.
+///
+/// If an operand copies `_c`, it must happen before the assignment `_d = _c`, otherwise it is UB.
+/// This means that replacing it by a copy of `_a` if ok, since this copy happens before `_c` is
+/// moved, and therefore that `_d` is moved.
+#[instrument(level = "trace", skip(ssa, body))]
+fn compute_copy_classes(
+    ssa: &SsaLocals,
+    body: &Body<'_>,
+) -> (IndexVec<Local, Local>, BitSet<Local>) {
+    let mut copies = IndexVec::from_fn_n(|l| l, body.local_decls.len());
+    let mut fully_moved = BitSet::new_filled(copies.len());
+
+    for &local in &ssa.assignment_order {
+        debug!(?local);
+
+        if local == RETURN_PLACE {
+            // `_0` is special, we cannot rename it.
+            continue;
+        }
+
+        // This is not SSA: mark that we don't know the value.
+        debug!(assignments = ?ssa.assignments[local]);
+        let Set1::One(LocationExtended::Plain(loc)) = ssa.assignments[local] else { continue };
+
+        // `loc` must point to a direct assignment to `local`.
+        let Either::Left(stmt) = body.stmt_at(loc) else { bug!() };
+        let Some((_target, rvalue)) = stmt.kind.as_assign() else { bug!() };
+        assert_eq!(_target.as_local(), Some(local));
+
+        let (Rvalue::Use(Operand::Copy(place) | Operand::Move(place)) | Rvalue::CopyForDeref(place))
+            = rvalue
+        else { continue };
+
+        let Some(rhs) = place.as_local() else { continue };
+        let Set1::One(_) = ssa.assignments[rhs] else { continue };
+
+        // We visit in `assignment_order`, ie. reverse post-order, so `rhs` has been
+        // visited before `local`, and we just have to copy the representing local.
+        copies[local] = copies[rhs];
+
+        if let Rvalue::Use(Operand::Copy(_)) | Rvalue::CopyForDeref(_) = rvalue {
+            fully_moved.remove(rhs);
+        }
+    }
+
+    debug!(?copies);
+
+    // Invariant: `copies` must point to the head of an equivalence class.
+    #[cfg(debug_assertions)]
+    for &head in copies.iter() {
+        assert_eq!(copies[head], head);
+    }
+
+    meet_copy_equivalence(&copies, &mut fully_moved);
+
+    (copies, fully_moved)
+}
+
+/// Make a property uniform on a copy equivalence class by removing elements.
+fn meet_copy_equivalence(copies: &IndexVec<Local, Local>, property: &mut BitSet<Local>) {
+    // Consolidate to have a local iff all its copies are.
+    //
+    // `copies` defines equivalence classes between locals.  The `local`s that recursively
+    // move/copy the same local all have the same `head`.
+    for (local, &head) in copies.iter_enumerated() {
+        // If any copy does not have `property`, then the head is not.
+        if !property.contains(local) {
+            property.remove(head);
+        }
+    }
+    for (local, &head) in copies.iter_enumerated() {
+        // If any copy does not have `property`, then the head doesn't either,
+        // then no copy has `property`.
+        if !property.contains(head) {
+            property.remove(local);
+        }
+    }
+
+    // Verify that we correctly computed equivalence classes.
+    #[cfg(debug_assertions)]
+    for (local, &head) in copies.iter_enumerated() {
+        assert_eq!(property.contains(local), property.contains(head));
+    }
+}
+
+/// Utility to help performing subtitution of `*pattern` by `target`.
+struct Replacer<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    fully_moved: BitSet<Local>,
+    storage_to_remove: BitSet<Local>,
+    copy_classes: IndexVec<Local, Local>,
+}
+
+impl<'tcx> MutVisitor<'tcx> for Replacer<'tcx> {
+    fn tcx(&self) -> TyCtxt<'tcx> {
+        self.tcx
+    }
+
+    fn visit_local(&mut self, local: &mut Local, _: PlaceContext, _: Location) {
+        *local = self.copy_classes[*local];
+    }
+
+    fn visit_operand(&mut self, operand: &mut Operand<'tcx>, loc: Location) {
+        if let Operand::Move(place) = *operand
+            && let Some(local) = place.as_local()
+            && !self.fully_moved.contains(local)
+        {
+            *operand = Operand::Copy(place);
+        }
+        self.super_operand(operand, loc);
+    }
+
+    fn visit_statement(&mut self, stmt: &mut Statement<'tcx>, loc: Location) {
+        if let StatementKind::StorageLive(l) | StatementKind::StorageDead(l) = stmt.kind
+            && self.storage_to_remove.contains(l)
+        {
+            stmt.make_nop();
+        }
+        if let StatementKind::Assign(box (ref place, _)) = stmt.kind
+            && let Some(l) = place.as_local()
+            && self.copy_classes[l] != l
+        {
+            stmt.make_nop();
+        }
+        self.super_statement(stmt, loc);
+    }
+}

compiler/rustc_mir_transform/src/lib.rs

@@ -54,6 +54,7 @@ mod const_debuginfo;
 mod const_goto;
 mod const_prop;
 mod const_prop_lint;
+mod copy_prop;
 mod coverage;
 mod dataflow_const_prop;
 mod dead_store_elimination;
@@ -556,6 +557,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
             &instcombine::InstCombine,
             &separate_const_switch::SeparateConstSwitch,
             &simplify::SimplifyLocals::new("before-const-prop"),
+            &copy_prop::CopyProp,
             //
             // FIXME(#70073): This pass is responsible for both optimization as well as some lints.
             &const_prop::ConstProp,

tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff

@@ -56,25 +56,13 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/const_debuginfo.rs:+1:9: +1:10
           _1 = const 1_u8;                 // scope 0 at $DIR/const_debuginfo.rs:+1:13: +1:16
-          StorageLive(_2);                 // scope 1 at $DIR/const_debuginfo.rs:+2:9: +2:10
           _2 = const 2_u8;                 // scope 1 at $DIR/const_debuginfo.rs:+2:13: +2:16
-          StorageLive(_3);                 // scope 2 at $DIR/const_debuginfo.rs:+3:9: +3:10
           _3 = const 3_u8;                 // scope 2 at $DIR/const_debuginfo.rs:+3:13: +3:16
           StorageLive(_4);                 // scope 3 at $DIR/const_debuginfo.rs:+4:9: +4:12
           StorageLive(_5);                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:20
-          StorageLive(_6);                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:16
-          _6 = const 1_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:16
-          StorageLive(_7);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          _7 = const 2_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
           _5 = const 3_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:20
-          StorageDead(_7);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          StorageDead(_6);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          StorageLive(_8);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
-          _8 = const 3_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           _4 = const 6_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:24
-          StorageDead(_8);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           StorageDead(_5);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           StorageLive(_9);                 // scope 4 at $DIR/const_debuginfo.rs:+6:9: +6:10
           _9 = const "hello, world!";      // scope 4 at $DIR/const_debuginfo.rs:+6:13: +6:28
@@ -117,9 +105,6 @@
           StorageDead(_16);                // scope 5 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_9);                 // scope 4 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_4);                 // scope 3 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_3);                 // scope 2 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_2);                 // scope 1 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_1);                 // scope 0 at $DIR/const_debuginfo.rs:+14:1: +14:2
           return;                          // scope 0 at $DIR/const_debuginfo.rs:+14:2: +14:2
       }
   }

tests/mir-opt/const_prop/bad_op_mod_by_zero.main.ConstProp.diff

@@ -18,35 +18,27 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:+1:9: +1:10
           _1 = const 0_i32;                // scope 0 at $DIR/bad_op_mod_by_zero.rs:+1:13: +1:14
           StorageLive(_2);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:9: +2:11
-          StorageLive(_3);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
--         _3 = _1;                         // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
--         _4 = Eq(_3, const 0_i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+-         _4 = Eq(_1, const 0_i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         assert(!move _4, "attempt to calculate the remainder of `{}` with a divisor of zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _3 = const 0_i32;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
 +         _4 = const true;                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         assert(!const true, "attempt to calculate the remainder of `{}` with a divisor of zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
       }
   
       bb1: {
--         _5 = Eq(_3, const -1_i32);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+          _5 = Eq(_1, const -1_i32);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         _6 = Eq(const 1_i32, const i32::MIN); // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         _7 = BitAnd(move _5, move _6);   // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
--         assert(!move _7, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _5 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+-         assert(!move _7, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _1) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         _6 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         _7 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         assert(!const false, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, const 0_i32) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
++         assert(!const false, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _1) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
       }
   
       bb2: {
--         _2 = Rem(const 1_i32, move _3);  // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _2 = Rem(const 1_i32, const 0_i32); // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-          StorageDead(_3);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
+          _2 = Rem(const 1_i32, _1);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
           StorageDead(_2);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+3:1: +3:2
-          StorageDead(_1);                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:+3:1: +3:2
           return;                          // scope 0 at $DIR/bad_op_mod_by_zero.rs:+3:2: +3:2
       }
   }

tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff

@@ -23,16 +23,13 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          StorageLive(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _8 = const _;                    // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
                                            // mir::Constant
                                            // + span: $DIR/bad_op_unsafe_oob_for_slices.rs:5:25: 5:35
                                            // + literal: Const { ty: &[i32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
-          _3 = _8;                         // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          _2 = &raw const (*_3);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
+          _2 = &raw const (*_8);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _1 = move _2 as *const [i32] (Pointer(Unsize)); // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           StorageDead(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:34: +1:35
-          StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:35: +1:36
           StorageLive(_4);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:13: +3:15
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
           _5 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24

tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff

@@ -23,16 +23,13 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          StorageLive(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _8 = const _;                    // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
                                            // mir::Constant
                                            // + span: $DIR/bad_op_unsafe_oob_for_slices.rs:5:25: 5:35
                                            // + literal: Const { ty: &[i32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
-          _3 = _8;                         // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          _2 = &raw const (*_3);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
+          _2 = &raw const (*_8);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _1 = move _2 as *const [i32] (Pointer(Unsize)); // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           StorageDead(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:34: +1:35
-          StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:35: +1:36
           StorageLive(_4);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:13: +3:15
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
           _5 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24

tests/mir-opt/const_prop/boolean_identities.test.ConstProp.diff

@@ -12,18 +12,12 @@
   
       bb0: {
           StorageLive(_3);                 // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
-          StorageLive(_4);                 // scope 0 at $DIR/boolean_identities.rs:+1:6: +1:7
-          _4 = _2;                         // scope 0 at $DIR/boolean_identities.rs:+1:6: +1:7
--         _3 = BitOr(move _4, const true); // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
+-         _3 = BitOr(_2, const true);      // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
 +         _3 = const true;                 // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
-          StorageDead(_4);                 // scope 0 at $DIR/boolean_identities.rs:+1:14: +1:15
           StorageLive(_5);                 // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-          StorageLive(_6);                 // scope 0 at $DIR/boolean_identities.rs:+1:19: +1:20
-          _6 = _1;                         // scope 0 at $DIR/boolean_identities.rs:+1:19: +1:20
--         _5 = BitAnd(move _6, const false); // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-+         _5 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-          StorageDead(_6);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29
+-         _5 = BitAnd(_1, const false);    // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
 -         _0 = BitAnd(move _3, move _5);   // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:29
++         _5 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
 +         _0 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:29
           StorageDead(_5);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29
           StorageDead(_3);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29

tests/mir-opt/const_prop/mult_by_zero.test.ConstProp.diff

@@ -7,11 +7,8 @@
       let mut _2: i32;                     // in scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
-          _2 = _1;                         // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
--         _0 = Mul(move _2, const 0_i32);  // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
+-         _0 = Mul(_1, const 0_i32);       // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
 +         _0 = const 0_i32;                // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
-          StorageDead(_2);                 // scope 0 at $DIR/mult_by_zero.rs:+1:7: +1:8
           return;                          // scope 0 at $DIR/mult_by_zero.rs:+2:2: +2:2
       }
   }

tests/mir-opt/const_prop/scalar_literal_propagation.main.ConstProp.diff

@@ -11,13 +11,9 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/scalar_literal_propagation.rs:+1:9: +1:10
           _1 = const 1_u32;                // scope 0 at $DIR/scalar_literal_propagation.rs:+1:13: +1:14
           StorageLive(_2);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
-          StorageLive(_3);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
--         _3 = _1;                         // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
--         _2 = consume(move _3) -> bb1;    // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
-+         _3 = const 1_u32;                // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
+-         _2 = consume(_1) -> bb1;         // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
 +         _2 = consume(const 1_u32) -> bb1; // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
                                            // mir::Constant
                                            // + span: $DIR/scalar_literal_propagation.rs:4:5: 4:12
@@ -25,9 +21,7 @@
       }
   
       bb1: {
-          StorageDead(_3);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:14: +2:15
           StorageDead(_2);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:15: +2:16
-          StorageDead(_1);                 // scope 0 at $DIR/scalar_literal_propagation.rs:+3:1: +3:2
           return;                          // scope 0 at $DIR/scalar_literal_propagation.rs:+3:2: +3:2
       }
   }

tests/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff

@@ -16,23 +16,13 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
           _1 = const u8::MAX;              // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          StorageLive(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
           _2 = const 1_u8;                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          StorageLive(_3);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          _3 = const u8::MAX;              // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          StorageLive(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          _4 = const 1_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
           _5 = CheckedAdd(const u8::MAX, const 1_u8); // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
           assert(!move (_5.1: bool), "attempt to compute `{} + {}`, which would overflow", const u8::MAX, const 1_u8) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
       }
   
       bb1: {
-          StorageDead(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          StorageDead(_3);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          StorageDead(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          StorageDead(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
           return;                          // scope 0 at $DIR/inherit_overflow.rs:+4:2: +4:2
       }
   }

tests/mir-opt/div_overflow.const_dividend.PreCodegen.after.mir

@@ -11,7 +11,7 @@ fn const_dividend(_1: i32) -> i32 {
     }
 
     bb1: {
-        _0 = Div(const 256_i32, move _1); // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
+        _0 = Div(const 256_i32, _1);     // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
         return;                          // scope 0 at $DIR/div_overflow.rs:+2:2: +2:2
     }
 }

tests/mir-opt/div_overflow.const_divisor.PreCodegen.after.mir

@@ -5,7 +5,7 @@ fn const_divisor(_1: i32) -> i32 {
     let mut _0: i32;                     // return place in scope 0 at $DIR/div_overflow.rs:+0:33: +0:36
 
     bb0: {
-        _0 = Div(move _1, const 256_i32); // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
+        _0 = Div(_1, const 256_i32);     // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
         return;                          // scope 0 at $DIR/div_overflow.rs:+2:2: +2:2
     }
 }

tests/mir-opt/funky_arms.float_to_exponential_common.ConstProp.diff

@@ -79,59 +79,42 @@
       }
   
       bb6: {
-          StorageLive(_10);                // scope 3 at $DIR/funky_arms.rs:+13:17: +13:26
           _10 = ((_7 as Some).0: usize);   // scope 3 at $DIR/funky_arms.rs:+13:17: +13:26
           StorageLive(_11);                // scope 3 at $DIR/funky_arms.rs:+15:43: +15:46
           _11 = &mut (*_1);                // scope 3 at $DIR/funky_arms.rs:+15:43: +15:46
-          StorageLive(_12);                // scope 3 at $DIR/funky_arms.rs:+15:48: +15:51
-          _12 = _2;                        // scope 3 at $DIR/funky_arms.rs:+15:48: +15:51
           StorageLive(_13);                // scope 3 at $DIR/funky_arms.rs:+15:53: +15:57
           _13 = _6;                        // scope 3 at $DIR/funky_arms.rs:+15:53: +15:57
           StorageLive(_14);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:79
           StorageLive(_15);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
-          StorageLive(_16);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:68
-          _16 = _10;                       // scope 3 at $DIR/funky_arms.rs:+15:59: +15:68
-          _15 = move _16 as u32 (IntToInt); // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
-          StorageDead(_16);                // scope 3 at $DIR/funky_arms.rs:+15:74: +15:75
+          _15 = _10 as u32 (IntToInt);     // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
           _14 = Add(move _15, const 1_u32); // scope 3 at $DIR/funky_arms.rs:+15:59: +15:79
           StorageDead(_15);                // scope 3 at $DIR/funky_arms.rs:+15:78: +15:79
-          StorageLive(_17);                // scope 3 at $DIR/funky_arms.rs:+15:81: +15:86
-          _17 = _3;                        // scope 3 at $DIR/funky_arms.rs:+15:81: +15:86
-          _0 = float_to_exponential_common_exact::<T>(move _11, move _12, move _13, move _14, move _17) -> bb7; // scope 3 at $DIR/funky_arms.rs:+15:9: +15:87
+          _0 = float_to_exponential_common_exact::<T>(move _11, _2, move _13, move _14, _3) -> bb7; // scope 3 at $DIR/funky_arms.rs:+15:9: +15:87
                                            // mir::Constant
                                            // + span: $DIR/funky_arms.rs:26:9: 26:42
                                            // + literal: Const { ty: for<'a, 'b, 'c> fn(&'a mut Formatter<'b>, &'c T, Sign, u32, bool) -> Result<(), std::fmt::Error> {float_to_exponential_common_exact::<T>}, val: Value(<ZST>) }
       }
   
       bb7: {
-          StorageDead(_17);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
           StorageDead(_14);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
           StorageDead(_13);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
-          StorageDead(_12);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
           StorageDead(_11);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
-          StorageDead(_10);                // scope 2 at $DIR/funky_arms.rs:+16:5: +16:6
           goto -> bb10;                    // scope 2 at $DIR/funky_arms.rs:+13:5: +18:6
       }
   
       bb8: {
           StorageLive(_18);                // scope 2 at $DIR/funky_arms.rs:+17:46: +17:49
           _18 = &mut (*_1);                // scope 2 at $DIR/funky_arms.rs:+17:46: +17:49
-          StorageLive(_19);                // scope 2 at $DIR/funky_arms.rs:+17:51: +17:54
-          _19 = _2;                        // scope 2 at $DIR/funky_arms.rs:+17:51: +17:54
           StorageLive(_20);                // scope 2 at $DIR/funky_arms.rs:+17:56: +17:60
           _20 = _6;                        // scope 2 at $DIR/funky_arms.rs:+17:56: +17:60
-          StorageLive(_21);                // scope 2 at $DIR/funky_arms.rs:+17:62: +17:67
-          _21 = _3;                        // scope 2 at $DIR/funky_arms.rs:+17:62: +17:67
-          _0 = float_to_exponential_common_shortest::<T>(move _18, move _19, move _20, move _21) -> bb9; // scope 2 at $DIR/funky_arms.rs:+17:9: +17:68
+          _0 = float_to_exponential_common_shortest::<T>(move _18, _2, move _20, _3) -> bb9; // scope 2 at $DIR/funky_arms.rs:+17:9: +17:68
                                            // mir::Constant
                                            // + span: $DIR/funky_arms.rs:28:9: 28:45
                                            // + literal: Const { ty: for<'a, 'b, 'c> fn(&'a mut Formatter<'b>, &'c T, Sign, bool) -> Result<(), std::fmt::Error> {float_to_exponential_common_shortest::<T>}, val: Value(<ZST>) }
       }
   
       bb9: {
-          StorageDead(_21);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
           StorageDead(_20);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
-          StorageDead(_19);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
           StorageDead(_18);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
           goto -> bb10;                    // scope 2 at $DIR/funky_arms.rs:+13:5: +18:6
       }

tests/mir-opt/inline/dyn_trait.get_query.Inline.diff

@@ -35,8 +35,8 @@
           _4 = &(*_2);                     // scope 1 at $DIR/dyn_trait.rs:+2:23: +2:24
 -         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> bb2; // scope 1 at $DIR/dyn_trait.rs:+2:5: +2:25
 +         StorageLive(_5);                 // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
-+         _5 = move _4 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
-+         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(move _5) -> bb2; // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
++         _5 = _4 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(_5) -> bb2; // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
 -                                          // + span: $DIR/dyn_trait.rs:34:5: 34:22
 -                                          // + literal: Const { ty: for<'a> fn(&'a <Q as Query>::C) {try_execute_query::<<Q as Query>::C>}, val: Value(<ZST>) }

tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff

@@ -17,7 +17,7 @@
           _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (Pointer(Unsize)); // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
           StorageDead(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
 -         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> bb1; // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:16
-+         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(move _2) -> bb1; // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
++         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(_2) -> bb1; // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
 -                                          // + span: $DIR/dyn_trait.rs:27:5: 27:13
 -                                          // + literal: Const { ty: for<'a> fn(&'a (dyn Cache<V = <C as Cache>::V> + 'a)) {mk_cycle::<<C as Cache>::V>}, val: Value(<ZST>) }

tests/mir-opt/inline/inline_any_operand.bar.Inline.after.mir

@@ -26,7 +26,7 @@ fn bar() -> bool {
         _3 = const 1_i32;                // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageLive(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         _4 = const -1_i32;               // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
-        _0 = Eq(move _3, move _4);       // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:11
+        _0 = Eq(_3, _4);                 // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:11
         StorageDead(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageDead(_3);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageDead(_2);                 // scope 1 at $DIR/inline_any_operand.rs:+2:12: +2:13

tests/mir-opt/inline/inline_generator.main.Inline.diff

@@ -92,7 +92,7 @@
 + 
 +     bb3: {
 +         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
-+         switchInt(move _7) -> [0: bb5, otherwise: bb4]; // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
++         switchInt(_7) -> [0: bb5, otherwise: bb4]; // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
 +     }
 + 
 +     bb4: {
@@ -118,7 +118,7 @@
 +         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
 +         StorageDead(_8);                 // scope 6 at $DIR/inline_generator.rs:15:38: 15:39
 +         Deinit(_1);                      // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
-+         ((_1 as Complete).0: bool) = move _7; // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         ((_1 as Complete).0: bool) = _7; // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
 +         discriminant(_1) = 1;            // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
 +         _12 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
 +         discriminant((*_12)) = 1;        // scope 6 at $DIR/inline_generator.rs:15:41: 15:41

tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir

@@ -15,7 +15,7 @@ fn test2(_1: &dyn X) -> bool {
         _3 = &(*_1);                     // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
         _2 = move _3 as &dyn X (Pointer(Unsize)); // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
         StorageDead(_3);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
-        _0 = <dyn X as X>::y(move _2) -> bb1; // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
+        _0 = <dyn X as X>::y(_2) -> bb1; // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
                                          // mir::Constant
                                          // + span: $DIR/inline_trait_method_2.rs:10:7: 10:8
                                          // + literal: Const { ty: for<'a> fn(&'a dyn X) -> bool {<dyn X as X>::y}, val: Value(<ZST>) }

tests/mir-opt/issue_101973.inner.ConstProp.diff

@@ -15,7 +15,7 @@
       let mut _10: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
       let mut _11: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
       scope 1 (inlined imm8) {             // at $DIR/issue_101973.rs:14:5: 14:17
-          debug x => _5;                   // in scope 1 at $DIR/issue_101973.rs:5:13: 5:14
+          debug x => _1;                   // in scope 1 at $DIR/issue_101973.rs:5:13: 5:14
           let mut _12: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:27
           let mut _13: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
           let mut _14: (u32, bool);        // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
@@ -33,18 +33,14 @@
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
           StorageLive(_3);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:58
-          StorageLive(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:17
-          StorageLive(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
-          _5 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
           StorageLive(_12);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:27
           StorageLive(_13);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
-          _14 = CheckedShr(_5, const 0_i32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
+          _14 = CheckedShr(_1, const 0_i32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
           assert(!move (_14.1: bool), "attempt to shift right by `{}`, which would overflow", const 0_i32) -> bb3; // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
       }
   
       bb1: {
           _8 = move (_10.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
-          StorageDead(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:44: +1:45
           _7 = BitAnd(move _8, const 15_u32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
           StorageDead(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:51: +1:52
           _11 = CheckedShl(_7, const 1_i32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
@@ -54,11 +50,7 @@
       bb2: {
           _6 = move (_11.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
           StorageDead(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:56: +1:57
-          StorageLive(_15);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _15 = _4;                        // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageLive(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _16 = _6;                        // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _3 = rotate_right::<u32>(move _15, move _16) -> bb4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
+          _3 = rotate_right::<u32>(_4, _6) -> bb4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
                                            // mir::Constant
                                            // + span: $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
                                            // + literal: Const { ty: extern "rust-intrinsic" fn(u32, u32) -> u32 {rotate_right::<u32>}, val: Value(<ZST>) }
@@ -70,21 +62,13 @@
           StorageDead(_13);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
           _4 = BitOr(const 0_u32, move _12); // scope 2 at $DIR/issue_101973.rs:7:5: 7:27
           StorageDead(_12);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
-          StorageDead(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:16: +1:17
-          StorageLive(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
           StorageLive(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
           StorageLive(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
-          StorageLive(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
-          _9 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
-          _10 = CheckedShr(_9, const 8_i32); // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+          _10 = CheckedShr(_1, const 8_i32); // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
           assert(!move (_10.1: bool), "attempt to shift right by `{}`, which would overflow", const 8_i32) -> bb1; // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
       }
   
       bb4: {
-          StorageDead(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageDead(_15);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageDead(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
-          StorageDead(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
           _2 = move _3 as i32 (IntToInt);  // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
           StorageDead(_3);                 // scope 0 at $DIR/issue_101973.rs:+1:64: +1:65
           _0 = move _2 as i64 (IntToInt);  // scope 0 at $DIR/issue_101973.rs:+1:5: +1:72

tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.diff

@@ -29,24 +29,10 @@
   
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/issue_76432.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          StorageLive(_4);                 // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
           StorageLive(_5);                 // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
-          StorageLive(_6);                 // scope 0 at $DIR/issue_76432.rs:+1:21: +1:22
-          _6 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:21: +1:22
-          StorageLive(_7);                 // scope 0 at $DIR/issue_76432.rs:+1:24: +1:25
-          _7 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:24: +1:25
-          StorageLive(_8);                 // scope 0 at $DIR/issue_76432.rs:+1:27: +1:28
-          _8 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:27: +1:28
-          _5 = [move _6, move _7, move _8]; // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
-          StorageDead(_8);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_7);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_6);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
+          _5 = [_1, _1, _1];               // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
           _4 = &_5;                        // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          _3 = _4;                         // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          _2 = move _3 as &[T] (Pointer(Unsize)); // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          StorageDead(_3);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_4);                 // scope 0 at $DIR/issue_76432.rs:+1:29: +1:30
+          _2 = _4 as &[T] (Pointer(Unsize)); // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
           _9 = Len((*_2));                 // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33
           _10 = const 3_usize;             // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33
 -         _11 = Eq(move _9, const 3_usize); // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33

tests/mir-opt/lower_array_len_e2e.array_bound.PreCodegen.after.mir

@@ -5,27 +5,23 @@ fn array_bound(_1: usize, _2: &[u8; N]) -> u8 {
     debug slice => _2;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:50: +0:55
     let mut _0: u8;                      // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:70: +0:72
     let mut _3: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-    let mut _6: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let mut _7: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+    let mut _6: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
 
     bb0: {
         StorageLive(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        _4 = _1;                         // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        StorageLive(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _3 = Lt(move _4, move _5);       // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageDead(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
+        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+        _4 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+        _3 = Lt(_1, move _4);            // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
         StorageDead(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
         switchInt(move _3) -> [0: bb3, otherwise: bb1]; // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
     }
 
     bb1: {
-        _6 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        _7 = Lt(_1, _6);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        _6 = Lt(_1, _5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        assert(move _6, "index out of bounds: the length is {} but the index is {}", move _5, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
     }
 
     bb2: {

tests/mir-opt/lower_array_len_e2e.array_bound_mut.PreCodegen.after.mir

@@ -5,30 +5,26 @@ fn array_bound_mut(_1: usize, _2: &mut [u8; N]) -> u8 {
     debug slice => _2;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:54: +0:59
     let mut _0: u8;                      // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:78: +0:80
     let mut _3: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-    let mut _6: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let mut _7: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let _8: usize;                       // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-    let mut _9: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-    let mut _10: bool;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
+    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+    let mut _6: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+    let _7: usize;                       // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
+    let mut _8: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
+    let mut _9: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
 
     bb0: {
         StorageLive(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        _4 = _1;                         // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        StorageLive(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _3 = Lt(move _4, move _5);       // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageDead(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
+        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+        _4 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
+        _3 = Lt(_1, move _4);            // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
         StorageDead(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
         switchInt(move _3) -> [0: bb3, otherwise: bb1]; // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
     }
 
     bb1: {
-        _6 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        _7 = Lt(_1, _6);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        _6 = Lt(_1, _5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
+        assert(move _6, "index out of bounds: the length is {} but the index is {}", move _5, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
     }
 
     bb2: {
@@ -37,16 +33,16 @@ fn array_bound_mut(_1: usize, _2: &mut [u8; N]) -> u8 {
     }
 
     bb3: {
-        StorageLive(_8);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-        _8 = const 0_usize;              // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-        _9 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-        _10 = Lt(const 0_usize, _9);     // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-        assert(move _10, "index out of bounds: the length is {} but the index is {}", move _9, const 0_usize) -> bb4; // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
+        StorageLive(_7);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
+        _7 = const 0_usize;              // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
+        _8 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
+        _9 = Lt(const 0_usize, _8);      // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
+        assert(move _9, "index out of bounds: the length is {} but the index is {}", move _8, const 0_usize) -> bb4; // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
     }
 
     bb4: {
-        (*_2)[_8] = const 42_u8;         // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:22
-        StorageDead(_8);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:22: +4:23
+        (*_2)[_7] = const 42_u8;         // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:22
+        StorageDead(_7);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:22: +4:23
         _0 = const 42_u8;                // scope 0 at $DIR/lower_array_len_e2e.rs:+6:9: +6:11
         goto -> bb5;                     // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +7:6
     }

tests/mir-opt/simple_option_map_e2e.ezmap.PreCodegen.after.mir

@@ -37,7 +37,7 @@ fn ezmap(_1: Option<i32>) -> Option<i32> {
     bb3: {
         _5 = move ((_1 as Some).0: i32); // scope 1 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
         StorageLive(_4);                 // scope 2 at $DIR/simple_option_map_e2e.rs:7:25: 7:29
-        _4 = Add(move _5, const 1_i32);  // scope 3 at $DIR/simple_option_map_e2e.rs:+1:16: +1:21
+        _4 = Add(_5, const 1_i32);       // scope 3 at $DIR/simple_option_map_e2e.rs:+1:16: +1:21
         Deinit(_0);                      // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
         ((_0 as Some).0: i32) = move _4; // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
         discriminant(_0) = 1;            // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30

tests/mir-opt/simplify_match.main.ConstProp.diff

@@ -10,13 +10,8 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/simplify_match.rs:+1:11: +1:31
-          StorageLive(_2);                 // scope 0 at $DIR/simplify_match.rs:+1:17: +1:18
           _2 = const false;                // scope 0 at $DIR/simplify_match.rs:+1:21: +1:26
--         _1 = _2;                         // scope 1 at $DIR/simplify_match.rs:+1:28: +1:29
-+         _1 = const false;                // scope 1 at $DIR/simplify_match.rs:+1:28: +1:29
-          StorageDead(_2);                 // scope 0 at $DIR/simplify_match.rs:+1:30: +1:31
--         switchInt(_1) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
+-         switchInt(_2) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
 +         switchInt(const false) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
       }
   
@@ -32,7 +27,6 @@
       }
   
       bb3: {
-          StorageDead(_1);                 // scope 0 at $DIR/simplify_match.rs:+5:1: +5:2
           return;                          // scope 0 at $DIR/simplify_match.rs:+5:2: +5:2
       }
   }

tests/mir-opt/slice_filter.rs

@@ -1,21 +1,18 @@
 fn main() {
     let input = vec![];
-
-    // 1761ms on my machine
     let _variant_a_result = variant_a(&input);
-
-    //  656ms on my machine
     let _variant_b_result = variant_b(&input);
 }
 
-
-// EMIT_MIR slice_filter.variant_a-{closure#0}.DestinationPropagation.diff
 pub fn variant_a(input: &[(usize, usize, usize, usize)]) -> usize {
     input.iter().filter(|(a, b, c, d)| a <= c && d <= b || c <= a && b <= d).count()
 }
 
-
-// EMIT_MIR slice_filter.variant_b-{closure#0}.DestinationPropagation.diff
 pub fn variant_b(input: &[(usize, usize, usize, usize)]) -> usize {
     input.iter().filter(|&&(a, b, c, d)| a <= c && d <= b || c <= a && b <= d).count()
 }
+
+// EMIT_MIR slice_filter.variant_a-{closure#0}.CopyProp.diff
+// EMIT_MIR slice_filter.variant_a-{closure#0}.DestinationPropagation.diff
+// EMIT_MIR slice_filter.variant_b-{closure#0}.CopyProp.diff
+// EMIT_MIR slice_filter.variant_b-{closure#0}.DestinationPropagation.diff

tests/mir-opt/slice_filter.variant_a-{closure#0}.CopyProp.diff

@@ -0,0 +1,283 @@
+- // MIR for `variant_a::{closure#0}` before CopyProp
++ // MIR for `variant_a::{closure#0}` after CopyProp
+  
+  fn variant_a::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:8:25: 8:39], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:40: +0:40
+      let _3: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+      let _4: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+      let _5: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+      let _6: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:56
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:46
+      let mut _9: &&usize;                 // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:41
+      let mut _10: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let _11: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:56
+      let mut _13: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:51
+      let mut _14: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let _15: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let mut _16: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:76
+      let mut _17: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:66
+      let mut _18: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:61
+      let mut _19: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let _20: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let mut _21: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:76
+      let mut _22: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:71
+      let mut _23: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let _24: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let mut _25: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _26: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _27: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _28: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:27: +0:28
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:30: +0:31
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:33: +0:34
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:36: +0:37
+          scope 2 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:40: 8:46
+              debug self => _9;            // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _10;          // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _29: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _30: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _31: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _32: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 3 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _29;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _30;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _31;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _32;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _33: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _34: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 4 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:60: 8:66
+              debug self => _18;           // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _19;          // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _35: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _36: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _37: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _38: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 5 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _35;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _36;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _37;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _38;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _39: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _40: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 6 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:50: 8:56
+              debug self => _13;           // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _14;          // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _41: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _42: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _43: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _44: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 7 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _41;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _42;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _43;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _44;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _45: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _46: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 8 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:70: 8:76
+              debug self => _22;           // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _23;          // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _47: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _48: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _49: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _50: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 9 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _47;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _48;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _49;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _50;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _51: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _52: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _25 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _3 = &((*_25).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+-         StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _26 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _4 = &((*_26).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+-         StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _27 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _5 = &((*_27).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+-         StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _28 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _6 = &((*_28).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:46
+          StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          _9 = &_3;                        // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+-         StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+-         _11 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+-         _10 = &_11;                      // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+-         StorageLive(_29);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _10 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _31 = deref_copy (*_9);          // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _29 = _31;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_30);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _32 = deref_copy (*_10);         // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _30 = _32;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _33 = (*_29);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _33 = (*_31);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _34 = (*_30);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _34 = (*_32);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _8 = Le(move _33, move _34);     // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_30);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_29);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb2: {
+          StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:66
+          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          _18 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+-         StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+-         _20 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+-         _19 = &_20;                      // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+-         StorageLive(_35);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _19 = &_3;                       // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _37 = deref_copy (*_18);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _35 = _37;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_36);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _38 = deref_copy (*_19);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _36 = _38;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _39 = (*_35);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _39 = (*_37);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _40 = (*_36);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _40 = (*_38);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _17 = Le(move _39, move _40);    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_36);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_35);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          switchInt(move _17) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb3: {
+          StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:76: +0:76
+      }
+  
+      bb4: {
+          _7 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb5: {
+          StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
+          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          _13 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         _15 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         _14 = &_15;                      // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         StorageLive(_41);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _14 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _43 = deref_copy (*_13);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _41 = _43;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_42);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _44 = deref_copy (*_14);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _42 = _44;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _45 = (*_41);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _45 = (*_43);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _46 = (*_42);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _46 = (*_44);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _12 = Le(move _45, move _46);    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_42);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_41);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _7 = move _12;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb6: {
+          _16 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb7: {
+          StorageLive(_21);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
+          StorageLive(_22);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          _22 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          StorageLive(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageLive(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _24 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _23 = &_24;                      // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageLive(_47);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _23 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _49 = deref_copy (*_22);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _47 = _49;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_48);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _50 = deref_copy (*_23);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _48 = _50;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _51 = (*_47);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _51 = (*_49);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _52 = (*_48);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _52 = (*_50);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _21 = Le(move _51, move _52);    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_48);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_47);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_22);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _16 = move _21;                  // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb8: {
+          StorageDead(_21);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _0 = move _16;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  }
+  

tests/mir-opt/slice_filter.variant_a-{closure#0}.DestinationPropagation.diff

@@ -1,7 +1,7 @@
 - // MIR for `variant_a::{closure#0}` before DestinationPropagation
 + // MIR for `variant_a::{closure#0}` after DestinationPropagation
   
-  fn variant_a::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:14:25: 14:39], _2: &&(usize, usize, usize, usize)) -> bool {
+  fn variant_a::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:8:25: 8:39], _2: &&(usize, usize, usize, usize)) -> bool {
       let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:40: +0:40
       let _3: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
       let _4: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
@@ -11,141 +11,100 @@
       let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:46
       let mut _9: &&usize;                 // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:41
       let mut _10: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
-      let _11: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
-      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:56
-      let mut _13: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:51
-      let mut _14: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
-      let _15: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
-      let mut _16: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:76
-      let mut _17: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:66
-      let mut _18: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:61
-      let mut _19: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
-      let _20: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
-      let mut _21: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:76
-      let mut _22: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:71
-      let mut _23: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
-      let _24: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
-      let mut _25: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
-      let mut _26: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
-      let mut _27: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
-      let mut _28: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:56
+      let mut _12: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:51
+      let mut _13: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let mut _14: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:76
+      let mut _15: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:66
+      let mut _16: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:61
+      let mut _17: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let mut _18: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:76
+      let mut _19: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:71
+      let mut _20: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let mut _21: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _22: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _23: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _24: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
       scope 1 {
           debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:27: +0:28
           debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:30: +0:31
           debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:33: +0:34
           debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:36: +0:37
-          scope 2 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:14:40: 14:46
+          scope 2 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:40: 8:46
               debug self => _9;            // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
               debug other => _10;          // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _29: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _30: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _31: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _32: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _25: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _26: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
               scope 3 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug self => _29;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug other => _30;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug self => _31;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug other => _32;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _33: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _34: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _25;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _26;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _27: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _28: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
               }
           }
-          scope 4 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:14:60: 14:66
-              debug self => _18;           // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              debug other => _19;          // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _35: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _36: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _37: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _38: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          scope 4 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:60: 8:66
+              debug self => _16;           // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _17;          // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _29: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _30: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
               scope 5 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug self => _35;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug other => _36;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug self => _37;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug other => _38;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _39: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _40: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _29;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _30;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _31: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _32: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
               }
           }
-          scope 6 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:14:50: 14:56
-              debug self => _13;           // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              debug other => _14;          // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _41: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _42: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _43: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _44: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          scope 6 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:50: 8:56
+              debug self => _12;           // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _13;          // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _33: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _34: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
               scope 7 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug self => _41;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug other => _42;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug self => _43;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug other => _44;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _45: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _46: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _33;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _34;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _35: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _36: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
               }
           }
-          scope 8 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:14:70: 14:76
-              debug self => _22;           // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              debug other => _23;          // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _47: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _48: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _49: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-              let mut _50: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          scope 8 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:70: 8:76
+              debug self => _19;           // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _20;          // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _37: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _38: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
               scope 9 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug self => _47;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
--                 debug other => _48;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug self => _49;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+                 debug other => _50;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _51: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-                  let mut _52: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _37;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _38;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _39: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _40: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
               }
           }
       }
   
       bb0: {
-          StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
-          _25 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
-          _3 = &((*_25).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
-          StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
-          _26 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
-          _4 = &((*_26).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
-          StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
-          _27 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
-          _5 = &((*_27).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
-          StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
-          _28 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
-          _6 = &((*_28).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _21 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _3 = &((*_21).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _22 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _4 = &((*_22).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _23 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _5 = &((*_23).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _24 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _6 = &((*_24).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
 -         StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
           StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:46
           StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
           _9 = &_3;                        // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
           StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
-          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
-          _11 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
-          _10 = &_11;                      // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
--         StorageLive(_29);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _31 = deref_copy (*_9);          // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _29 = _31;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageLive(_30);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _32 = deref_copy (*_10);         // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _30 = _32;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _33 = (*_29);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _33 = (*_31);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _34 = (*_30);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _34 = (*_32);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _8 = Le(move _33, move _34);     // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_30);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_29);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _10 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _25 = deref_copy (*_9);          // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _26 = deref_copy (*_10);         // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_27);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _27 = (*_25);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_28);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _28 = (*_26);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _8 = Le(move _27, move _28);     // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_28);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_27);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
           StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
           StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
           switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
@@ -157,159 +116,104 @@
       }
   
       bb2: {
--         StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+-         StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
-          StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:66
-          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
-          _18 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
-          StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          _20 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          _19 = &_20;                      // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
--         StorageLive(_35);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _37 = deref_copy (*_18);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _35 = _37;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageLive(_36);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _38 = deref_copy (*_19);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _36 = _38;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _39 = (*_35);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _39 = (*_37);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _40 = (*_36);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _40 = (*_38);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _17 = Le(move _39, move _40);    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_36);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_35);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
-          switchInt(move _17) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:66
+          StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          _16 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _17 = &_3;                       // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _29 = deref_copy (*_16);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _30 = deref_copy (*_17);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_31);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _31 = (*_29);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_32);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _32 = (*_30);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _15 = Le(move _31, move _32);    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_32);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_31);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          switchInt(move _15) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
       }
   
       bb3: {
--         StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
 -         StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
           return;                          // scope 0 at $DIR/slice_filter.rs:+0:76: +0:76
       }
   
       bb4: {
--         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
           StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
           goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
       }
   
       bb5: {
--         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
+-         StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
-          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
-          _13 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
-          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
-          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
-          _15 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
-          _14 = &_15;                      // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
--         StorageLive(_41);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _43 = deref_copy (*_13);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _41 = _43;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageLive(_42);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _44 = deref_copy (*_14);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _42 = _44;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _45 = (*_41);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _45 = (*_43);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _46 = (*_42);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _46 = (*_44);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _12 = Le(move _45, move _46);    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_42);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_41);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
-          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          _12 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _13 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _33 = deref_copy (*_12);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _34 = deref_copy (*_13);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_35);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _35 = (*_33);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_36);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _36 = (*_34);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _11 = Le(move _35, move _36);    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_36);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_35);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
           StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
--         _7 = move _12;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
--         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         _7 = move _11;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+-         StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
           StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
 -         switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
-+         switchInt(move _12) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
++         switchInt(move _11) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
       }
   
       bb6: {
--         _16 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+-         _14 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
 +         _0 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
           goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
       }
   
       bb7: {
--         StorageLive(_21);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
+-         StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
-          StorageLive(_22);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
-          _22 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
-          StorageLive(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageLive(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          _24 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          _23 = &_24;                      // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
--         StorageLive(_47);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _49 = deref_copy (*_22);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _47 = _49;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageLive(_48);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          _50 = deref_copy (*_23);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _48 = _50;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _51 = (*_47);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _51 = (*_49);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageLive(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _52 = (*_48);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         _21 = Le(move _51, move _52);    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _52 = (*_50);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         _0 = Le(move _51, move _52);     // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_48);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
--         StorageDead(_47);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-+         nop;                             // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
-          StorageDead(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_22);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
--         _16 = move _21;                  // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          _19 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _20 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _37 = deref_copy (*_19);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _38 = deref_copy (*_20);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_39);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _39 = (*_37);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_40);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _40 = (*_38);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _18 = Le(move _39, move _40);    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _0 = Le(move _39, move _40);     // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_40);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_39);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _14 = move _18;                  // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
           goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
       }
   
       bb8: {
--         StorageDead(_21);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
-          StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
--         _0 = move _16;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _0 = move _14;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
           goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
       }

tests/mir-opt/slice_filter.variant_b-{closure#0}.CopyProp.diff

@@ -0,0 +1,139 @@
+- // MIR for `variant_b::{closure#0}` before CopyProp
++ // MIR for `variant_b::{closure#0}` after CopyProp
+  
+  fn variant_b::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:12:25: 12:41], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:42: +0:42
+      let _3: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+      let _4: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+      let _5: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+      let _6: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:58
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:48
+      let mut _9: usize;                   // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:43
+      let mut _10: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:47: +0:48
+      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:58
+      let mut _12: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:53
+      let mut _13: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:57: +0:58
+      let mut _14: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:78
+      let mut _15: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:68
+      let mut _16: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:63
+      let mut _17: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:67: +0:68
+      let mut _18: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:78
+      let mut _19: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:73
+      let mut _20: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+      let mut _21: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _22: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _23: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _24: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
+      }
+  
+      bb0: {
+-         StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _21 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _3 = ((*_21).0: usize);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+-         StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _22 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _4 = ((*_22).1: usize);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+-         StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _23 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _5 = ((*_23).2: usize);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+-         StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _24 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _6 = ((*_24).3: usize);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+-         StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
+-         _9 = _3;                         // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
+-         StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         _10 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         _8 = Le(move _9, move _10);      // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+-         StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
++         _8 = Le(_3, _5);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb2: {
+          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+-         StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
+-         _16 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
+-         StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         _17 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         _15 = Le(move _16, move _17);    // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+-         StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
++         _15 = Le(_5, _3);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          switchInt(move _15) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb3: {
+          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:78: +0:78
+      }
+  
+      bb4: {
+          _7 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb5: {
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
+-         _12 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
+-         StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         _13 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         _11 = Le(move _12, move _13);    // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
++         _11 = Le(_6, _4);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+          _7 = move _11;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb6: {
+          _14 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb7: {
+          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
+-         _19 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
+-         StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _20 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _18 = Le(move _19, move _20);    // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         _18 = Le(_4, _6);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+          _14 = move _18;                  // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb8: {
+          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          _0 = move _14;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  }
+  

tests/mir-opt/slice_filter.variant_b-{closure#0}.DestinationPropagation.diff

@@ -1,7 +1,7 @@
 - // MIR for `variant_b::{closure#0}` before DestinationPropagation
 + // MIR for `variant_b::{closure#0}` after DestinationPropagation
   
-  fn variant_b::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:20:25: 20:41], _2: &&(usize, usize, usize, usize)) -> bool {
+  fn variant_b::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:12:25: 12:41], _2: &&(usize, usize, usize, usize)) -> bool {
       let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:42: +0:42
       let _3: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
       let _4: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
@@ -9,66 +9,34 @@
       let _6: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
       let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:58
       let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:48
-      let mut _9: usize;                   // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:43
-      let mut _10: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:47: +0:48
-      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:58
-      let mut _12: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:53
-      let mut _13: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:57: +0:58
-      let mut _14: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:78
-      let mut _15: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:68
-      let mut _16: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:63
-      let mut _17: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:67: +0:68
-      let mut _18: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:78
-      let mut _19: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:73
-      let mut _20: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
-      let mut _21: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
-      let mut _22: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
-      let mut _23: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
-      let mut _24: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _9: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:58
+      let mut _10: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:78
+      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:68
+      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:78
+      let mut _13: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _14: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _15: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _16: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
       scope 1 {
--         debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
--         debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
--         debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
--         debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
-+         debug a => _17;                  // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
-+         debug b => _19;                  // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
-+         debug c => _16;                  // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
-+         debug d => _20;                  // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
       }
   
       bb0: {
--         StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
-          _21 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
--         _3 = ((*_21).0: usize);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
--         StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
-+         _17 = ((*_21).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
-          _22 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
--         _4 = ((*_22).1: usize);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
--         StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
-+         _19 = ((*_22).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
-          _23 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
--         _5 = ((*_23).2: usize);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
--         StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
-+         _16 = ((*_23).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
-          _24 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
--         _6 = ((*_24).3: usize);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _13 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _3 = ((*_13).0: usize);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _14 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _4 = ((*_14).1: usize);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _15 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _5 = ((*_15).2: usize);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _16 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _6 = ((*_16).3: usize);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
 -         StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
-+         _20 = ((*_24).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
           StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
-          StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
--         _9 = _3;                         // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
-+         _9 = _17;                        // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
-          StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
--         _10 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
-+         _10 = _16;                       // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
-          _8 = Le(move _9, move _10);      // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
-          StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
-          StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+          _8 = Le(_3, _5);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
           switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
       }
   
@@ -78,102 +46,62 @@
       }
   
       bb2: {
--         StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+-         StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
-          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
--         StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
--         _16 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
--         StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
--         _17 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-          _15 = Le(move _16, move _17);    // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
--         StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
--         StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
-          switchInt(move _15) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          _11 = Le(_5, _3);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          switchInt(move _11) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
       }
   
       bb3: {
--         StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
 -         StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
--         StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
--         StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
--         StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
           return;                          // scope 0 at $DIR/slice_filter.rs:+0:78: +0:78
       }
   
       bb4: {
--         StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
           StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
           goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
       }
   
       bb5: {
--         StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
-          StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
--         _12 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
-+         _12 = _20;                       // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
-          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
--         _13 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
-+         _13 = _19;                       // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
-          _11 = Le(move _12, move _13);    // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
-          StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
-          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
--         _7 = move _11;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
--         StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          _9 = Le(_6, _4);                 // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         _7 = move _9;                    // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
           StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
 -         switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
-+         switchInt(move _11) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
++         switchInt(move _9) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
       }
   
       bb6: {
--         _14 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+-         _10 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
 +         _0 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
           goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
       }
   
       bb7: {
--         StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
--         StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
--         _19 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
--         StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         _20 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         _18 = Le(move _19, move _20);    // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
--         StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         _14 = move _18;                  // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+-         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         _12 = Le(_4, _6);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         _10 = move _12;                  // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
-+         _0 = Le(move _19, move _20);     // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
-+         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         _0 = Le(_4, _6);                 // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
           goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
       }
   
       bb8: {
--         StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
-          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
--         _0 = move _14;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _0 = move _10;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
 +         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
           goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
       }

tests/mir-opt/try_identity_e2e.new.PreCodegen.after.mir

@@ -5,11 +5,11 @@ fn new(_1: Result<T, E>) -> Result<T, E> {
     let mut _0: std::result::Result<T, E>; // return place in scope 0 at $DIR/try_identity_e2e.rs:+0:34: +0:46
     let mut _2: std::ops::ControlFlow<E, T>; // in scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
     let mut _3: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+4:17: +4:22
-    let mut _4: T;                       // in scope 0 at $DIR/try_identity_e2e.rs:+4:48: +4:49
-    let mut _5: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+5:46: +5:47
+    let _4: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+4:20: +4:21
+    let _5: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+5:21: +5:22
     let mut _6: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+8:13: +8:37
     let _7: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+8:35: +8:36
-    let mut _8: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+9:49: +9:50
+    let _8: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+9:32: +9:33
     scope 1 {
         debug v => _4;                   // in scope 1 at $DIR/try_identity_e2e.rs:+4:20: +4:21
     }

tests/mir-opt/try_identity_e2e.old.PreCodegen.after.mir

@@ -5,7 +5,7 @@ fn old(_1: Result<T, E>) -> Result<T, E> {
     let mut _0: std::result::Result<T, E>; // return place in scope 0 at $DIR/try_identity_e2e.rs:+0:34: +0:46
     let mut _2: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+3:13: +3:18
     let _3: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+3:16: +3:17
-    let mut _4: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+4:34: +4:35
+    let _4: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+4:17: +4:18
     scope 1 {
         debug v => _3;                   // in scope 1 at $DIR/try_identity_e2e.rs:+3:16: +3:17
     }

tests/mir-opt/while_storage.while_loop.PreCodegen.after.mir

@@ -4,9 +4,7 @@ fn while_loop(_1: bool) -> () {
     debug c => _1;                       // in scope 0 at $DIR/while_storage.rs:+0:15: +0:16
     let mut _0: ();                      // return place in scope 0 at $DIR/while_storage.rs:+0:24: +0:24
     let mut _2: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:11: +1:22
-    let mut _3: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-    let mut _4: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:12: +2:23
-    let mut _5: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:21: +2:22
+    let mut _3: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:12: +2:23
 
     bb0: {
         goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
@@ -14,41 +12,35 @@ fn while_loop(_1: bool) -> () {
 
     bb1: {
         StorageLive(_2);                 // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
-        StorageLive(_3);                 // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-        _3 = _1;                         // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-        _2 = get_bool(move _3) -> bb2;   // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
+        _2 = get_bool(_1) -> bb2;        // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
                                          // mir::Constant
                                          // + span: $DIR/while_storage.rs:10:11: 10:19
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+1:21: +1:22
         switchInt(move _2) -> [0: bb7, otherwise: bb3]; // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
     }
 
     bb3: {
-        StorageLive(_4);                 // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
-        StorageLive(_5);                 // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
-        _5 = _1;                         // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
-        _4 = get_bool(move _5) -> bb4;   // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        StorageLive(_3);                 // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        _3 = get_bool(_1) -> bb4;        // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
                                          // mir::Constant
                                          // + span: $DIR/while_storage.rs:11:12: 11:20
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb4: {
-        StorageDead(_5);                 // scope 0 at $DIR/while_storage.rs:+2:22: +2:23
-        switchInt(move _4) -> [0: bb6, otherwise: bb5]; // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        switchInt(move _3) -> [0: bb6, otherwise: bb5]; // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
     }
 
     bb5: {
-        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
+        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
         goto -> bb7;                     // scope 0 at no-location
     }
 
     bb6: {
-        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
+        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
         StorageDead(_2);                 // scope 0 at $DIR/while_storage.rs:+5:5: +5:6
         goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
     }