Auto merge of #128265 - DianQK:instsimplify-before-inline, r=saethlin

Perform instsimplify before inline to eliminate some trivial calls I am currently working on #128081. In the current pipeline, we can get the following clone statements ([godbolt](https://rust.godbolt.org/z/931316fhP)): ``` bb0: { StorageLive(_2); _2 = ((*_1).0: i32); StorageLive(_3); _3 = ((*_1).1: u64); _0 = Foo { a: move _2, b: move _3 }; StorageDead(_3); StorageDead(_2); return; } ``` Analyzing such statements will be simple and fast. We don't need to consider branches or some interfering statements. However, this requires us to run `InstSimplify`, `ReferencePropagation`, and `SimplifyCFG` at least once. I can introduce a new pass, but I think the best place for it would be within `InstSimplify`. I put `InstSimplify` before `Inline`, which takes some of the burden away from `Inline`. r? `@saethlin`
2024-10-30 05:51:58 +00:00 · 2024-07-29 12:36:57 +00:00 · 2024-07-29 12:36:57 +00:00 · 4db3d12e6f
commit 4db3d12e6f
parent 56c698c711 ae681c940d
83 changed files with 226 additions and 182 deletions
--- a/compiler/rustc_mir_transform/src/instsimplify.rs
+++ b/compiler/rustc_mir_transform/src/instsimplify.rs
@ -13,9 +13,25 @@ use rustc_target::spec::abi::Abi;
 use crate::simplify::simplify_duplicate_switch_targets;
 use crate::take_array;

-pub struct InstSimplify;
+pub enum InstSimplify {
+    BeforeInline,
+    AfterSimplifyCfg,
+}
+
+impl InstSimplify {
+    pub fn name(&self) -> &'static str {
+        match self {
+            InstSimplify::BeforeInline => "InstSimplify-before-inline",
+            InstSimplify::AfterSimplifyCfg => "InstSimplify-after-simplifycfg",
+        }
+    }
+}

 impl<'tcx> MirPass<'tcx> for InstSimplify {
+    fn name(&self) -> &'static str {
+        self.name()
+    }
+
    fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
        sess.mir_opt_level() > 0
    }
--- a/compiler/rustc_mir_transform/src/lib.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@ -571,6 +571,8 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
            // Has to be done before inlining, otherwise actual call will be almost always inlined.
            // Also simple, so can just do first
            &lower_slice_len::LowerSliceLenCalls,
+            // Perform instsimplify before inline to eliminate some trivial calls (like clone shims).
+            &instsimplify::InstSimplify::BeforeInline,
            // Perform inlining, which may add a lot of code.
            &inline::Inline,
            // Code from other crates may have storage markers, so this needs to happen after inlining.
@ -590,7 +592,8 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
            &match_branches::MatchBranchSimplification,
            // inst combine is after MatchBranchSimplification to clean up Ne(_1, false)
            &multiple_return_terminators::MultipleReturnTerminators,
-            &instsimplify::InstSimplify,
+            // After simplifycfg, it allows us to discover new opportunities for peephole optimizations.
+            &instsimplify::InstSimplify::AfterSimplifyCfg,
            &simplify::SimplifyLocals::BeforeConstProp,
            &dead_store_elimination::DeadStoreElimination::Initial,
            &gvn::GVN,
--- a/compiler/rustc_mir_transform/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@ -155,7 +155,7 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceKind<'tcx>) -> Body<
            &deref_separator::Derefer,
            &remove_noop_landing_pads::RemoveNoopLandingPads,
            &simplify::SimplifyCfg::MakeShim,
-            &instsimplify::InstSimplify,
+            &instsimplify::InstSimplify::BeforeInline,
            &abort_unwinding_calls::AbortUnwindingCalls,
            &add_call_guards::CriticalCallEdges,
        ],
--- a/tests/incremental/hashes/call_expressions.rs
+++ b/tests/incremental/hashes/call_expressions.rs
@ -162,7 +162,7 @@ pub fn change_to_ufcs() {
 }

 #[cfg(not(any(cfail1,cfail4)))]
-#[rustc_clean(cfg="cfail2", except="opt_hir_owner_nodes,typeck")]
+#[rustc_clean(cfg="cfail2", except="opt_hir_owner_nodes,optimized_mir,typeck")]
 #[rustc_clean(cfg="cfail3")]
 #[rustc_clean(cfg="cfail5", except="opt_hir_owner_nodes,optimized_mir,typeck")]
 #[rustc_clean(cfg="cfail6")]
--- a/tests/mir-opt/const_prop/slice_len.rs
+++ b/tests/mir-opt/const_prop/slice_len.rs
@ -1,5 +1,5 @@
 //@ test-mir-pass: GVN
-//@ compile-flags: -Zmir-enable-passes=+InstSimplify -Zdump-mir-exclude-alloc-bytes
+//@ compile-flags: -Zmir-enable-passes=+InstSimplify-after-simplifycfg -Zdump-mir-exclude-alloc-bytes
 // EMIT_MIR_FOR_EACH_PANIC_STRATEGY
 // EMIT_MIR_FOR_EACH_BIT_WIDTH

--- a/tests/mir-opt/dataflow-const-prop/slice_len.rs
+++ b/tests/mir-opt/dataflow-const-prop/slice_len.rs
@ -1,6 +1,6 @@
 // EMIT_MIR_FOR_EACH_PANIC_STRATEGY
 //@ test-mir-pass: DataflowConstProp
-//@ compile-flags: -Zmir-enable-passes=+InstSimplify
+//@ compile-flags: -Zmir-enable-passes=+InstSimplify-after-simplifycfg
 // EMIT_MIR_FOR_EACH_BIT_WIDTH

 // EMIT_MIR slice_len.main.DataflowConstProp.diff
--- a/tests/mir-opt/inline/dyn_trait.get_query.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/dyn_trait.get_query.Inline.panic-abort.diff
@ -21,14 +21,14 @@
      bb0: {
          StorageLive(_2);
          StorageLive(_3);
-          _3 = &(*_1);
+          _3 = _1;
          _2 = <Q as Query>::cache::<T>(move _3) -> [return: bb1, unwind unreachable];
      }
  
      bb1: {
          StorageDead(_3);
          StorageLive(_4);
-          _4 = &(*_2);
+          _4 = _2;
 -         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> [return: bb2, unwind unreachable];
 +         StorageLive(_5);
 +         _5 = _4 as &dyn Cache<V = <Q as Query>::V> (PointerCoercion(Unsize));
--- a/tests/mir-opt/inline/dyn_trait.get_query.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/dyn_trait.get_query.Inline.panic-unwind.diff
@ -21,14 +21,14 @@
      bb0: {
          StorageLive(_2);
          StorageLive(_3);
-          _3 = &(*_1);
+          _3 = _1;
          _2 = <Q as Query>::cache::<T>(move _3) -> [return: bb1, unwind continue];
      }
  
      bb1: {
          StorageDead(_3);
          StorageLive(_4);
-          _4 = &(*_2);
+          _4 = _2;
 -         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> [return: bb2, unwind continue];
 +         StorageLive(_5);
 +         _5 = _4 as &dyn Cache<V = <Q as Query>::V> (PointerCoercion(Unsize));
--- a/tests/mir-opt/inline/dyn_trait.mk_cycle.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/dyn_trait.mk_cycle.Inline.panic-abort.diff
@ -8,7 +8,7 @@
  
      bb0: {
          StorageLive(_2);
-          _2 = &(*_1);
+          _2 = _1;
          _0 = <dyn Cache<V = V> as Cache>::store_nocache(move _2) -> [return: bb1, unwind unreachable];
      }
  
--- a/tests/mir-opt/inline/dyn_trait.mk_cycle.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/dyn_trait.mk_cycle.Inline.panic-unwind.diff
@ -8,7 +8,7 @@
  
      bb0: {
          StorageLive(_2);
-          _2 = &(*_1);
+          _2 = _1;
          _0 = <dyn Cache<V = V> as Cache>::store_nocache(move _2) -> [return: bb1, unwind continue];
      }
  
--- a/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.panic-abort.diff
+++ b/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.panic-abort.diff
@ -13,7 +13,7 @@
      bb0: {
          StorageLive(_2);
          StorageLive(_3);
-          _3 = &(*_1);
+          _3 = _1;
          _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (PointerCoercion(Unsize));
          StorageDead(_3);
 -         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> [return: bb1, unwind unreachable];
--- a/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.panic-unwind.diff
+++ b/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.panic-unwind.diff
@ -13,7 +13,7 @@
      bb0: {
          StorageLive(_2);
          StorageLive(_3);
-          _3 = &(*_1);
+          _3 = _1;
          _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (PointerCoercion(Unsize));
          StorageDead(_3);
 -         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> [return: bb1, unwind continue];
--- a/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
@ -26,9 +26,9 @@ fn foo(_1: T, _2: &i32) -> i32 {
        _4 = &_3;
        StorageLive(_5);
        StorageLive(_6);
-        _6 = &(*_2);
+        _6 = _2;
        StorageLive(_7);
-        _7 = &(*_2);
+        _7 = _2;
        _5 = (move _6, move _7);
        StorageLive(_8);
        _8 = move (_5.0: &i32);
--- a/tests/mir-opt/inline/inline_retag.bar.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_retag.bar.Inline.after.mir
@ -31,14 +31,14 @@ fn bar() -> bool {
        StorageLive(_4);
        _10 = const bar::promoted[1];
        Retag(_10);
-        _4 = &(*_10);
-        _3 = &(*_4);
+        _4 = _10;
+        _3 = _4;
        StorageLive(_6);
        StorageLive(_7);
        _9 = const bar::promoted[0];
        Retag(_9);
-        _7 = &(*_9);
-        _6 = &(*_7);
+        _7 = _9;
+        _6 = _7;
        Retag(_3);
        Retag(_6);
        StorageLive(_11);
--- a/tests/mir-opt/inline/inline_trait_method.test.Inline.after.panic-abort.mir
+++ b/tests/mir-opt/inline/inline_trait_method.test.Inline.after.panic-abort.mir
@ -7,7 +7,7 @@ fn test(_1: &dyn X) -> u32 {

    bb0: {
        StorageLive(_2);
-        _2 = &(*_1);
+        _2 = _1;
        _0 = <dyn X as X>::y(move _2) -> [return: bb1, unwind unreachable];
    }

--- a/tests/mir-opt/inline/inline_trait_method.test.Inline.after.panic-unwind.mir
+++ b/tests/mir-opt/inline/inline_trait_method.test.Inline.after.panic-unwind.mir
@ -7,7 +7,7 @@ fn test(_1: &dyn X) -> u32 {

    bb0: {
        StorageLive(_2);
-        _2 = &(*_1);
+        _2 = _1;
        _0 = <dyn X as X>::y(move _2) -> [return: bb1, unwind continue];
    }

--- a/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.panic-abort.mir
+++ b/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.panic-abort.mir
@ -12,8 +12,8 @@ fn test2(_1: &dyn X) -> bool {
    bb0: {
        StorageLive(_2);
        StorageLive(_3);
-        _3 = &(*_1);
-        _2 = move _3 as &dyn X (PointerCoercion(Unsize));
+        _3 = _1;
+        _2 = move _3;
        StorageDead(_3);
        _0 = <dyn X as X>::y(move _2) -> [return: bb1, unwind unreachable];
    }
--- a/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.panic-unwind.mir
+++ b/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.panic-unwind.mir
@ -12,8 +12,8 @@ fn test2(_1: &dyn X) -> bool {
    bb0: {
        StorageLive(_2);
        StorageLive(_3);
-        _3 = &(*_1);
-        _2 = move _3 as &dyn X (PointerCoercion(Unsize));
+        _3 = _1;
+        _2 = move _3;
        StorageDead(_3);
        _0 = <dyn X as X>::y(move _2) -> [return: bb1, unwind continue];
    }
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
@ -14,11 +14,11 @@ fn a(_1: &mut [T]) -> &mut [T] {
        StorageLive(_2);
        StorageLive(_3);
        StorageLive(_4);
-        _4 = &mut (*_1);
+        _4 = _1;
        _3 = _4;
-        _2 = &mut (*_3);
+        _2 = _3;
        StorageDead(_4);
-        _0 = &mut (*_2);
+        _0 = _2;
        StorageDead(_3);
        StorageDead(_2);
        return;
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
@ -16,7 +16,7 @@ fn b(_1: &mut Box<T>) -> &mut T {
        StorageLive(_2);
        StorageLive(_3);
        StorageLive(_4);
-        _4 = &mut (*_1);
+        _4 = _1;
        StorageLive(_5);
        StorageLive(_6);
        _5 = (*_4);
@ -24,9 +24,9 @@ fn b(_1: &mut Box<T>) -> &mut T {
        _3 = &mut (*_6);
        StorageDead(_6);
        StorageDead(_5);
-        _2 = &mut (*_3);
+        _2 = _3;
        StorageDead(_4);
-        _0 = &mut (*_2);
+        _0 = _2;
        StorageDead(_3);
        StorageDead(_2);
        return;
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.c.Inline.after.mir
@ -12,9 +12,9 @@ fn c(_1: &[T]) -> &[T] {
    bb0: {
        StorageLive(_2);
        StorageLive(_3);
-        _3 = &(*_1);
+        _3 = _1;
        _2 = _3;
-        _0 = &(*_2);
+        _0 = _2;
        StorageDead(_3);
        StorageDead(_2);
        return;
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.d.Inline.after.mir
@ -14,7 +14,7 @@ fn d(_1: &Box<T>) -> &T {
    bb0: {
        StorageLive(_2);
        StorageLive(_3);
-        _3 = &(*_1);
+        _3 = _1;
        StorageLive(_4);
        StorageLive(_5);
        _4 = (*_3);
@ -22,7 +22,7 @@ fn d(_1: &Box<T>) -> &T {
        _2 = &(*_5);
        StorageDead(_5);
        StorageDead(_4);
-        _0 = &(*_2);
+        _0 = _2;
        StorageDead(_3);
        StorageDead(_2);
        return;
--- a/tests/mir-opt/instsimplify/bool_compare.eq_false.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.eq_false.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `eq_false` before InstSimplify
-+ // MIR for `eq_false` after InstSimplify
+- // MIR for `eq_false` before InstSimplify-after-simplifycfg
+ // MIR for `eq_false` after InstSimplify-after-simplifycfg
  
  fn eq_false(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.eq_true.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.eq_true.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `eq_true` before InstSimplify
-+ // MIR for `eq_true` after InstSimplify
+- // MIR for `eq_true` before InstSimplify-after-simplifycfg
+ // MIR for `eq_true` after InstSimplify-after-simplifycfg
  
  fn eq_true(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.false_eq.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.false_eq.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `false_eq` before InstSimplify
-+ // MIR for `false_eq` after InstSimplify
+- // MIR for `false_eq` before InstSimplify-after-simplifycfg
+ // MIR for `false_eq` after InstSimplify-after-simplifycfg
  
  fn false_eq(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.false_ne.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.false_ne.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `false_ne` before InstSimplify
-+ // MIR for `false_ne` after InstSimplify
+- // MIR for `false_ne` before InstSimplify-after-simplifycfg
+ // MIR for `false_ne` after InstSimplify-after-simplifycfg
  
  fn false_ne(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.ne_false.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.ne_false.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `ne_false` before InstSimplify
-+ // MIR for `ne_false` after InstSimplify
+- // MIR for `ne_false` before InstSimplify-after-simplifycfg
+ // MIR for `ne_false` after InstSimplify-after-simplifycfg
  
  fn ne_false(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.ne_true.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.ne_true.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `ne_true` before InstSimplify
-+ // MIR for `ne_true` after InstSimplify
+- // MIR for `ne_true` before InstSimplify-after-simplifycfg
+ // MIR for `ne_true` after InstSimplify-after-simplifycfg
  
  fn ne_true(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.rs
+++ b/tests/mir-opt/instsimplify/bool_compare.rs
@ -1,55 +1,55 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg

-// EMIT_MIR bool_compare.eq_true.InstSimplify.diff
+// EMIT_MIR bool_compare.eq_true.InstSimplify-after-simplifycfg.diff
 fn eq_true(x: bool) -> u32 {
    // CHECK-LABEL: fn eq_true(
    // CHECK-NOT: Eq(
    if x == true { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.true_eq.InstSimplify.diff
+// EMIT_MIR bool_compare.true_eq.InstSimplify-after-simplifycfg.diff
 fn true_eq(x: bool) -> u32 {
    // CHECK-LABEL: fn true_eq(
    // CHECK-NOT: Eq(
    if true == x { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.ne_true.InstSimplify.diff
+// EMIT_MIR bool_compare.ne_true.InstSimplify-after-simplifycfg.diff
 fn ne_true(x: bool) -> u32 {
    // CHECK-LABEL: fn ne_true(
    // CHECK: Not(
    if x != true { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.true_ne.InstSimplify.diff
+// EMIT_MIR bool_compare.true_ne.InstSimplify-after-simplifycfg.diff
 fn true_ne(x: bool) -> u32 {
    // CHECK-LABEL: fn true_ne(
    // CHECK: Not(
    if true != x { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.eq_false.InstSimplify.diff
+// EMIT_MIR bool_compare.eq_false.InstSimplify-after-simplifycfg.diff
 fn eq_false(x: bool) -> u32 {
    // CHECK-LABEL: fn eq_false(
    // CHECK: Not(
    if x == false { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.false_eq.InstSimplify.diff
+// EMIT_MIR bool_compare.false_eq.InstSimplify-after-simplifycfg.diff
 fn false_eq(x: bool) -> u32 {
    // CHECK-LABEL: fn false_eq(
    // CHECK: Not(
    if false == x { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.ne_false.InstSimplify.diff
+// EMIT_MIR bool_compare.ne_false.InstSimplify-after-simplifycfg.diff
 fn ne_false(x: bool) -> u32 {
    // CHECK-LABEL: fn ne_false(
    // CHECK-NOT: Ne(
    if x != false { 0 } else { 1 }
 }

-// EMIT_MIR bool_compare.false_ne.InstSimplify.diff
+// EMIT_MIR bool_compare.false_ne.InstSimplify-after-simplifycfg.diff
 fn false_ne(x: bool) -> u32 {
    // CHECK-LABEL: fn false_ne(
    // CHECK-NOT: Ne(
--- a/tests/mir-opt/instsimplify/bool_compare.true_eq.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.true_eq.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `true_eq` before InstSimplify
-+ // MIR for `true_eq` after InstSimplify
+- // MIR for `true_eq` before InstSimplify-after-simplifycfg
+ // MIR for `true_eq` after InstSimplify-after-simplifycfg
  
  fn true_eq(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/bool_compare.true_ne.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/bool_compare.true_ne.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `true_ne` before InstSimplify
-+ // MIR for `true_ne` after InstSimplify
+- // MIR for `true_ne` before InstSimplify-after-simplifycfg
+ // MIR for `true_ne` after InstSimplify-after-simplifycfg
  
  fn true_ne(_1: bool) -> u32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/casts.redundant.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/casts.redundant.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `redundant` before InstSimplify
-+ // MIR for `redundant` after InstSimplify
+- // MIR for `redundant` before InstSimplify-after-simplifycfg
+ // MIR for `redundant` after InstSimplify-after-simplifycfg
  
  fn redundant(_1: *const &u8) -> *const &u8 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/casts.roundtrip.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/casts.roundtrip.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `roundtrip` before InstSimplify
-+ // MIR for `roundtrip` after InstSimplify
+- // MIR for `roundtrip` before InstSimplify-after-simplifycfg
+ // MIR for `roundtrip` after InstSimplify-after-simplifycfg
  
  fn roundtrip(_1: *const u8) -> *const u8 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/casts.rs
+++ b/tests/mir-opt/instsimplify/casts.rs
@ -1,4 +1,4 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg
 //@ compile-flags: -Zinline-mir
 #![crate_type = "lib"]
 #![feature(core_intrinsics)]
@ -8,7 +8,7 @@ fn generic_cast<T, U>(x: *const T) -> *const U {
    x as *const U
 }

-// EMIT_MIR casts.redundant.InstSimplify.diff
+// EMIT_MIR casts.redundant.InstSimplify-after-simplifycfg.diff
 pub fn redundant<'a, 'b: 'a>(x: *const &'a u8) -> *const &'a u8 {
    // CHECK-LABEL: fn redundant(
    // CHECK: inlined generic_cast
@ -16,7 +16,7 @@ pub fn redundant<'a, 'b: 'a>(x: *const &'a u8) -> *const &'a u8 {
    generic_cast::<&'a u8, &'b u8>(x) as *const &'a u8
 }

-// EMIT_MIR casts.roundtrip.InstSimplify.diff
+// EMIT_MIR casts.roundtrip.InstSimplify-after-simplifycfg.diff
 pub fn roundtrip(x: *const u8) -> *const u8 {
    // CHECK-LABEL: fn roundtrip(
    // CHECK: _4 = _1;
@ -25,7 +25,7 @@ pub fn roundtrip(x: *const u8) -> *const u8 {
    x as *mut u8 as *const u8
 }

-// EMIT_MIR casts.roundtrip.InstSimplify.diff
+// EMIT_MIR casts.roundtrip.InstSimplify-after-simplifycfg.diff
 pub fn cast_thin_via_aggregate(x: *const u8) -> *const () {
    // CHECK-LABEL: fn cast_thin_via_aggregate(
    // CHECK: _2 = _1;
--- a/tests/mir-opt/instsimplify/combine_array_len.norm2.InstSimplify-after-simplifycfg.panic-abort.diff
+++ b/tests/mir-opt/instsimplify/combine_array_len.norm2.InstSimplify-after-simplifycfg.panic-abort.diff
@ -1,5 +1,5 @@
- // MIR for `norm2` before InstSimplify
-+ // MIR for `norm2` after InstSimplify
+- // MIR for `norm2` before InstSimplify-after-simplifycfg
+ // MIR for `norm2` after InstSimplify-after-simplifycfg
  
  fn norm2(_1: [f32; 2]) -> f32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/combine_array_len.norm2.InstSimplify-after-simplifycfg.panic-unwind.diff
+++ b/tests/mir-opt/instsimplify/combine_array_len.norm2.InstSimplify-after-simplifycfg.panic-unwind.diff
@ -1,5 +1,5 @@
- // MIR for `norm2` before InstSimplify
-+ // MIR for `norm2` after InstSimplify
+- // MIR for `norm2` before InstSimplify-after-simplifycfg
+ // MIR for `norm2` after InstSimplify-after-simplifycfg
  
  fn norm2(_1: [f32; 2]) -> f32 {
      debug x => _1;
--- a/tests/mir-opt/instsimplify/combine_array_len.rs
+++ b/tests/mir-opt/instsimplify/combine_array_len.rs
@ -1,7 +1,7 @@
 // EMIT_MIR_FOR_EACH_PANIC_STRATEGY
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg

-// EMIT_MIR combine_array_len.norm2.InstSimplify.diff
+// EMIT_MIR combine_array_len.norm2.InstSimplify-after-simplifycfg.diff
 fn norm2(x: [f32; 2]) -> f32 {
    // CHECK-LABEL: fn norm2(
    // CHECK-NOT: Len(
--- a/tests/mir-opt/instsimplify/combine_clone_of_primitives.rs
+++ b/tests/mir-opt/instsimplify/combine_clone_of_primitives.rs
@ -1,7 +1,7 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg
 // EMIT_MIR_FOR_EACH_PANIC_STRATEGY

-// EMIT_MIR combine_clone_of_primitives.{impl#0}-clone.InstSimplify.diff
+// EMIT_MIR combine_clone_of_primitives.{impl#0}-clone.InstSimplify-after-simplifycfg.diff
 #[derive(Clone)]
 struct MyThing<T> {
    v: T,
--- a/tests/mir-opt/instsimplify/combine_clone_of_primitives.{impl#0}-clone.InstSimplify-after-simplifycfg.panic-abort.diff
+++ b/tests/mir-opt/instsimplify/combine_clone_of_primitives.{impl#0}-clone.InstSimplify-after-simplifycfg.panic-abort.diff
@ -1,5 +1,5 @@
- // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` before InstSimplify
-+ // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` after InstSimplify
+- // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` before InstSimplify-after-simplifycfg
+ // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` after InstSimplify-after-simplifycfg
  
  fn <impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone(_1: &MyThing<T>) -> MyThing<T> {
      debug self => _1;
--- a/tests/mir-opt/instsimplify/combine_clone_of_primitives.{impl#0}-clone.InstSimplify-after-simplifycfg.panic-unwind.diff
+++ b/tests/mir-opt/instsimplify/combine_clone_of_primitives.{impl#0}-clone.InstSimplify-after-simplifycfg.panic-unwind.diff
@ -1,5 +1,5 @@
- // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` before InstSimplify
-+ // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` after InstSimplify
+- // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` before InstSimplify-after-simplifycfg
+ // MIR for `<impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone` after InstSimplify-after-simplifycfg
  
  fn <impl at $DIR/combine_clone_of_primitives.rs:5:10: 5:15>::clone(_1: &MyThing<T>) -> MyThing<T> {
      debug self => _1;
--- a/tests/mir-opt/instsimplify/combine_transmutes.adt_transmutes.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/combine_transmutes.adt_transmutes.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `adt_transmutes` before InstSimplify
-+ // MIR for `adt_transmutes` after InstSimplify
+- // MIR for `adt_transmutes` before InstSimplify-after-simplifycfg
+ // MIR for `adt_transmutes` after InstSimplify-after-simplifycfg
  
  fn adt_transmutes() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/combine_transmutes.identity_transmutes.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/combine_transmutes.identity_transmutes.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `identity_transmutes` before InstSimplify
-+ // MIR for `identity_transmutes` after InstSimplify
+- // MIR for `identity_transmutes` before InstSimplify-after-simplifycfg
+ // MIR for `identity_transmutes` after InstSimplify-after-simplifycfg
  
  fn identity_transmutes() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/combine_transmutes.integer_transmutes.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/combine_transmutes.integer_transmutes.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `integer_transmutes` before InstSimplify
-+ // MIR for `integer_transmutes` after InstSimplify
+- // MIR for `integer_transmutes` before InstSimplify-after-simplifycfg
+ // MIR for `integer_transmutes` after InstSimplify-after-simplifycfg
  
  fn integer_transmutes() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/combine_transmutes.rs
+++ b/tests/mir-opt/instsimplify/combine_transmutes.rs
@ -1,4 +1,4 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg
 //@ compile-flags: -C panic=abort
 #![crate_type = "lib"]
 #![feature(core_intrinsics)]
@ -7,7 +7,7 @@
 use std::intrinsics::mir::*;
 use std::mem::{transmute, ManuallyDrop, MaybeUninit};

-// EMIT_MIR combine_transmutes.identity_transmutes.InstSimplify.diff
+// EMIT_MIR combine_transmutes.identity_transmutes.InstSimplify-after-simplifycfg.diff
 pub unsafe fn identity_transmutes() {
    // CHECK-LABEL: fn identity_transmutes(
    // CHECK-NOT: as i32 (Transmute);
@ -19,7 +19,7 @@ pub unsafe fn identity_transmutes() {
 }

 #[custom_mir(dialect = "runtime", phase = "initial")]
-// EMIT_MIR combine_transmutes.integer_transmutes.InstSimplify.diff
+// EMIT_MIR combine_transmutes.integer_transmutes.InstSimplify-after-simplifycfg.diff
 pub unsafe fn integer_transmutes() {
    // CHECK-LABEL: fn integer_transmutes(
    // CHECK-NOT: _i32 as u32 (Transmute);
@ -43,7 +43,7 @@ pub unsafe fn integer_transmutes() {
    }
 }

-// EMIT_MIR combine_transmutes.adt_transmutes.InstSimplify.diff
+// EMIT_MIR combine_transmutes.adt_transmutes.InstSimplify-after-simplifycfg.diff
 pub unsafe fn adt_transmutes() {
    // CHECK-LABEL: fn adt_transmutes(
    // CHECK: as u8 (Transmute);
--- a/tests/mir-opt/instsimplify/duplicate_switch_targets.assert_zero.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/duplicate_switch_targets.assert_zero.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `assert_zero` before InstSimplify
-+ // MIR for `assert_zero` after InstSimplify
+- // MIR for `assert_zero` before InstSimplify-after-simplifycfg
+ // MIR for `assert_zero` after InstSimplify-after-simplifycfg
  
  fn assert_zero(_1: u8) -> u8 {
      let mut _0: u8;
--- a/tests/mir-opt/instsimplify/duplicate_switch_targets.rs
+++ b/tests/mir-opt/instsimplify/duplicate_switch_targets.rs
@ -1,11 +1,11 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg

 #![feature(custom_mir, core_intrinsics)]
 #![crate_type = "lib"]

 use std::intrinsics::mir::*;

-// EMIT_MIR duplicate_switch_targets.assert_zero.InstSimplify.diff
+// EMIT_MIR duplicate_switch_targets.assert_zero.InstSimplify-after-simplifycfg.diff
 #[custom_mir(dialect = "runtime", phase = "post-cleanup")]
 pub unsafe fn assert_zero(x: u8) -> u8 {
    // CHECK-LABEL: fn assert_zero(
--- a/tests/mir-opt/instsimplify/intrinsic_asserts.generic.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/intrinsic_asserts.generic.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `generic` before InstSimplify
-+ // MIR for `generic` after InstSimplify
+- // MIR for `generic` before InstSimplify-after-simplifycfg
+ // MIR for `generic` after InstSimplify-after-simplifycfg
  
  fn generic() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/intrinsic_asserts.generic_ref.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/intrinsic_asserts.generic_ref.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `generic_ref` before InstSimplify
-+ // MIR for `generic_ref` after InstSimplify
+- // MIR for `generic_ref` before InstSimplify-after-simplifycfg
+ // MIR for `generic_ref` after InstSimplify-after-simplifycfg
  
  fn generic_ref() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/intrinsic_asserts.panics.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/intrinsic_asserts.panics.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `panics` before InstSimplify
-+ // MIR for `panics` after InstSimplify
+- // MIR for `panics` before InstSimplify-after-simplifycfg
+ // MIR for `panics` after InstSimplify-after-simplifycfg
  
  fn panics() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/intrinsic_asserts.removable.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/intrinsic_asserts.removable.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `removable` before InstSimplify
-+ // MIR for `removable` after InstSimplify
+- // MIR for `removable` before InstSimplify-after-simplifycfg
+ // MIR for `removable` after InstSimplify-after-simplifycfg
  
  fn removable() -> () {
      let mut _0: ();
--- a/tests/mir-opt/instsimplify/intrinsic_asserts.rs
+++ b/tests/mir-opt/instsimplify/intrinsic_asserts.rs
@ -1,10 +1,10 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg

 #![crate_type = "lib"]
 #![feature(core_intrinsics)]

 // All these assertions pass, so all the intrinsic calls should be deleted.
-// EMIT_MIR intrinsic_asserts.removable.InstSimplify.diff
+// EMIT_MIR intrinsic_asserts.removable.InstSimplify-after-simplifycfg.diff
 pub fn removable() {
    // CHECK-LABEL: fn removable(
    // CHECK-NOT: assert_inhabited
@ -18,7 +18,7 @@ pub fn removable() {
 enum Never {}

 // These assertions all diverge, so their target blocks should become None.
-// EMIT_MIR intrinsic_asserts.panics.InstSimplify.diff
+// EMIT_MIR intrinsic_asserts.panics.InstSimplify-after-simplifycfg.diff
 pub fn panics() {
    // CHECK-LABEL: fn panics(
    // CHECK: assert_inhabited::<Never>() -> unwind
@ -30,7 +30,7 @@ pub fn panics() {
 }

 // Whether or not these asserts pass isn't known, so they shouldn't be modified.
-// EMIT_MIR intrinsic_asserts.generic.InstSimplify.diff
+// EMIT_MIR intrinsic_asserts.generic.InstSimplify-after-simplifycfg.diff
 pub fn generic<T>() {
    // CHECK-LABEL: fn generic(
    // CHECK: assert_inhabited::<T>() -> [return:
@ -42,7 +42,7 @@ pub fn generic<T>() {
 }

 // Whether or not these asserts pass isn't known, so they shouldn't be modified.
-// EMIT_MIR intrinsic_asserts.generic_ref.InstSimplify.diff
+// EMIT_MIR intrinsic_asserts.generic_ref.InstSimplify-after-simplifycfg.diff
 pub fn generic_ref<T>() {
    // CHECK-LABEL: fn generic_ref(
    // CHECK: assert_mem_uninitialized_valid::<&T>() -> [return:
--- a/tests/mir-opt/instsimplify/ref_of_deref.pointers.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/ref_of_deref.pointers.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `pointers` before InstSimplify
-+ // MIR for `pointers` after InstSimplify
+- // MIR for `pointers` before InstSimplify-after-simplifycfg
+ // MIR for `pointers` after InstSimplify-after-simplifycfg
  
  fn pointers(_1: *const [i32], _2: *mut i32) -> () {
      debug const_ptr => _1;
--- a/tests/mir-opt/instsimplify/ref_of_deref.references.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/ref_of_deref.references.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `references` before InstSimplify
-+ // MIR for `references` after InstSimplify
+- // MIR for `references` before InstSimplify-after-simplifycfg
+ // MIR for `references` after InstSimplify-after-simplifycfg
  
  fn references(_1: &i32, _2: &mut [i32]) -> () {
      debug const_ref => _1;
--- a/tests/mir-opt/instsimplify/ref_of_deref.rs
+++ b/tests/mir-opt/instsimplify/ref_of_deref.rs
@ -1,11 +1,11 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg
 #![crate_type = "lib"]
 #![feature(raw_ref_op)]

 // For each of these, only 2 of the 6 should simplify,
 // as the others have the wrong types.

-// EMIT_MIR ref_of_deref.references.InstSimplify.diff
+// EMIT_MIR ref_of_deref.references.InstSimplify-after-simplifycfg.diff
 // CHECK-LABEL: references
 pub fn references(const_ref: &i32, mut_ref: &mut [i32]) {
    // CHECK: _3 = _1;
@ -22,7 +22,7 @@ pub fn references(const_ref: &i32, mut_ref: &mut [i32]) {
    let _f = &raw mut *mut_ref;
 }

-// EMIT_MIR ref_of_deref.pointers.InstSimplify.diff
+// EMIT_MIR ref_of_deref.pointers.InstSimplify-after-simplifycfg.diff
 // CHECK-LABEL: pointers
 pub unsafe fn pointers(const_ptr: *const [i32], mut_ptr: *mut i32) {
    // CHECK: _3 = &(*_1);
--- a/tests/mir-opt/instsimplify/ub_check.rs
+++ b/tests/mir-opt/instsimplify/ub_check.rs
@ -1,7 +1,7 @@
-//@ test-mir-pass: InstSimplify
+//@ test-mir-pass: InstSimplify-after-simplifycfg
 //@ compile-flags: -Cdebug-assertions=no -Zinline-mir

-// EMIT_MIR ub_check.unwrap_unchecked.InstSimplify.diff
+// EMIT_MIR ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
 pub fn unwrap_unchecked(x: Option<i32>) -> i32 {
    // CHECK-LABEL: fn unwrap_unchecked(
    // CHECK-NOT: UbChecks()
--- a/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/instsimplify/ub_check.unwrap_unchecked.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `unwrap_unchecked` before InstSimplify
-+ // MIR for `unwrap_unchecked` after InstSimplify
+- // MIR for `unwrap_unchecked` before InstSimplify-after-simplifycfg
+ // MIR for `unwrap_unchecked` after InstSimplify-after-simplifycfg
  
  fn unwrap_unchecked(_1: Option<i32>) -> i32 {
      debug x => _1;
--- a/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.panic-abort.diff
+++ b/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.panic-abort.diff
@ -5,7 +5,7 @@
      debug x => _1;
      let mut _0: ();
      let _2: &[T];
-      let mut _3: &[T; 3];
+      let _3: &[T; 3];
      let _4: [T; 3];
      let mut _5: usize;
      let mut _6: bool;
@ -23,12 +23,10 @@
      }
  
      bb0: {
-          StorageLive(_3);
          StorageLive(_4);
          _4 = [_1, _1, _1];
          _3 = &_4;
-          _2 = move _3 as &[T] (PointerCoercion(Unsize));
-          StorageDead(_3);
+          _2 = _3 as &[T] (PointerCoercion(Unsize));
          nop;
          nop;
          goto -> bb2;
--- a/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.panic-unwind.diff
+++ b/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.panic-unwind.diff
@ -5,7 +5,7 @@
      debug x => _1;
      let mut _0: ();
      let _2: &[T];
-      let mut _3: &[T; 3];
+      let _3: &[T; 3];
      let _4: [T; 3];
      let mut _5: usize;
      let mut _6: bool;
@ -23,12 +23,10 @@
      }
  
      bb0: {
-          StorageLive(_3);
          StorageLive(_4);
          _4 = [_1, _1, _1];
          _3 = &_4;
-          _2 = move _3 as &[T] (PointerCoercion(Unsize));
-          StorageDead(_3);
+          _2 = _3 as &[T] (PointerCoercion(Unsize));
          nop;
          nop;
          goto -> bb2;
--- a/tests/mir-opt/issue_78192.f.InstSimplify-after-simplifycfg.diff
+++ b/tests/mir-opt/issue_78192.f.InstSimplify-after-simplifycfg.diff
@ -1,5 +1,5 @@
- // MIR for `f` before InstSimplify
-+ // MIR for `f` after InstSimplify
+- // MIR for `f` before InstSimplify-after-simplifycfg
+ // MIR for `f` after InstSimplify-after-simplifycfg
  
  fn f(_1: &T) -> *const T {
      debug a => _1;
@ -17,8 +17,7 @@
          StorageLive(_4);
          _4 = &raw const (*_1);
          _3 = &_4;
-         _2 = &(*_3);
-+         _2 = _3;
+          _2 = _3;
          StorageDead(_3);
          _0 = (*_2);
          StorageDead(_4);
--- a/tests/mir-opt/issue_78192.rs
+++ b/tests/mir-opt/issue_78192.rs
@ -9,4 +9,4 @@ fn main() {
    f(&2);
 }

-// EMIT_MIR issue_78192.f.InstSimplify.diff
+// EMIT_MIR issue_78192.f.InstSimplify-after-simplifycfg.diff
--- a/tests/mir-opt/pre-codegen/issue_117368_print_invalid_constant.main.GVN.32bit.panic-abort.diff
+++ b/tests/mir-opt/pre-codegen/issue_117368_print_invalid_constant.main.GVN.32bit.panic-abort.diff
@ -24,7 +24,7 @@
              let _13: std::alloc::AllocError;
              let mut _14: !;
              let mut _15: &dyn std::fmt::Debug;
-              let mut _16: &std::alloc::AllocError;
+              let _16: &std::alloc::AllocError;
              scope 7 {
              }
              scope 8 {
@ -86,21 +86,21 @@
          StorageDead(_8);
          StorageDead(_7);
          StorageLive(_12);
+          StorageLive(_16);
          _12 = discriminant(_6);
          switchInt(move _12) -> [0: bb6, 1: bb5, otherwise: bb1];
      }
  
      bb5: {
          StorageLive(_15);
-          StorageLive(_16);
          _16 = &_13;
-          _15 = move _16 as &dyn std::fmt::Debug (PointerCoercion(Unsize));
-          StorageDead(_16);
+          _15 = _16 as &dyn std::fmt::Debug (PointerCoercion(Unsize));
          _14 = result::unwrap_failed(const "called `Result::unwrap()` on an `Err` value", move _15) -> unwind unreachable;
      }
  
      bb6: {
          _5 = move ((_6 as Ok).0: std::ptr::NonNull<[u8]>);
+          StorageDead(_16);
          StorageDead(_12);
          StorageDead(_6);
 -         StorageLive(_17);
--- a/tests/mir-opt/pre-codegen/issue_117368_print_invalid_constant.main.GVN.64bit.panic-abort.diff
+++ b/tests/mir-opt/pre-codegen/issue_117368_print_invalid_constant.main.GVN.64bit.panic-abort.diff
@ -24,7 +24,7 @@
              let _13: std::alloc::AllocError;
              let mut _14: !;
              let mut _15: &dyn std::fmt::Debug;
-              let mut _16: &std::alloc::AllocError;
+              let _16: &std::alloc::AllocError;
              scope 7 {
              }
              scope 8 {
@ -86,21 +86,21 @@
          StorageDead(_8);
          StorageDead(_7);
          StorageLive(_12);
+          StorageLive(_16);
          _12 = discriminant(_6);
          switchInt(move _12) -> [0: bb6, 1: bb5, otherwise: bb1];
      }
  
      bb5: {
          StorageLive(_15);
-          StorageLive(_16);
          _16 = &_13;
-          _15 = move _16 as &dyn std::fmt::Debug (PointerCoercion(Unsize));
-          StorageDead(_16);
+          _15 = _16 as &dyn std::fmt::Debug (PointerCoercion(Unsize));
          _14 = result::unwrap_failed(const "called `Result::unwrap()` on an `Err` value", move _15) -> unwind unreachable;
      }
  
      bb6: {
          _5 = move ((_6 as Ok).0: std::ptr::NonNull<[u8]>);
+          StorageDead(_16);
          StorageDead(_12);
          StorageDead(_6);
 -         StorageLive(_17);
--- a/tests/mir-opt/pre-codegen/loops.vec_move.PreCodegen.after.mir
+++ b/tests/mir-opt/pre-codegen/loops.vec_move.PreCodegen.after.mir
@ -30,13 +30,11 @@ fn vec_move(_1: Vec<impl Sized>) -> () {

    bb2: {
        StorageLive(_5);
-        StorageLive(_4);
        _4 = &mut _3;
        _5 = <std::vec::IntoIter<impl Sized> as Iterator>::next(move _4) -> [return: bb3, unwind: bb9];
    }

    bb3: {
-        StorageDead(_4);
        _6 = discriminant(_5);
        switchInt(move _6) -> [0: bb4, 1: bb6, otherwise: bb8];
    }
--- a/tests/mir-opt/pre-codegen/no_inlined_clone.rs
+++ b/tests/mir-opt/pre-codegen/no_inlined_clone.rs
@ -0,0 +1,12 @@
+#![crate_type = "lib"]
+
+// EMIT_MIR no_inlined_clone.{impl#0}-clone.PreCodegen.after.mir
+
+// CHECK-LABEL: ::clone(
+// CHECK-NOT: inlined clone::impls::<impl Clone for {{.*}}>::clone
+// CHECK: return;
+
+#[derive(Clone)]
+struct Foo {
+    a: i32,
+}
--- a/tests/mir-opt/pre-codegen/no_inlined_clone.{impl#0}-clone.PreCodegen.after.mir
+++ b/tests/mir-opt/pre-codegen/no_inlined_clone.{impl#0}-clone.PreCodegen.after.mir
@ -0,0 +1,15 @@
+// MIR for `<impl at $DIR/no_inlined_clone.rs:9:10: 9:15>::clone` after PreCodegen
+
+fn <impl at $DIR/no_inlined_clone.rs:9:10: 9:15>::clone(_1: &Foo) -> Foo {
+    debug self => _1;
+    let mut _0: Foo;
+    let mut _2: i32;
+
+    bb0: {
+        StorageLive(_2);
+        _2 = ((*_1).0: i32);
+        _0 = Foo { a: move _2 };
+        StorageDead(_2);
+        return;
+    }
+}
--- a/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.panic-abort.diff
+++ b/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.panic-abort.diff
@ -37,7 +37,7 @@
          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32];
          StorageLive(_5);
          _5 = const 3_usize;
-          _6 = Len(_4);
+          _6 = const 6_usize;
          _7 = Lt(_5, _6);
          assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> [success: bb2, unwind unreachable];
      }
--- a/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.panic-unwind.diff
+++ b/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.panic-unwind.diff
@ -37,7 +37,7 @@
          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32];
          StorageLive(_5);
          _5 = const 3_usize;
-          _6 = Len(_4);
+          _6 = const 6_usize;
          _7 = Lt(_5, _6);
          assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> [success: bb2, unwind continue];
      }
--- a/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.panic-abort.diff
+++ b/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.panic-abort.diff
@ -37,7 +37,7 @@
          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32];
          StorageLive(_5);
          _5 = const 3_usize;
-          _6 = Len(_4);
+          _6 = const 6_usize;
          _7 = Lt(_5, _6);
          assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> [success: bb2, unwind unreachable];
      }
--- a/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.panic-unwind.diff
+++ b/tests/mir-opt/pre-codegen/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.panic-unwind.diff
@ -37,7 +37,7 @@
          _4 = [const 0_i32, const 1_i32, const 2_i32, const 3_i32, const 4_i32, const 5_i32];
          StorageLive(_5);
          _5 = const 3_usize;
-          _6 = Len(_4);
+          _6 = const 6_usize;
          _7 = Lt(_5, _6);
          assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> [success: bb2, unwind continue];
      }
--- a/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-abort.mir
@ -36,13 +36,11 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {

    bb1: {
        StorageLive(_7);
-        StorageLive(_6);
        _6 = &mut _5;
        _7 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind unreachable];
    }

    bb2: {
-        StorageDead(_6);
        _8 = discriminant(_7);
        switchInt(move _8) -> [0: bb3, 1: bb5, otherwise: bb7];
    }
--- a/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/range_iter.inclusive_loop.PreCodegen.after.panic-unwind.mir
@ -36,13 +36,11 @@ fn inclusive_loop(_1: u32, _2: u32, _3: impl Fn(u32)) -> () {

    bb1: {
        StorageLive(_7);
-        StorageLive(_6);
        _6 = &mut _5;
        _7 = <RangeInclusive<u32> as iter::range::RangeInclusiveIteratorImpl>::spec_next(move _6) -> [return: bb2, unwind: bb8];
    }

    bb2: {
-        StorageDead(_6);
        _8 = discriminant(_7);
        switchInt(move _8) -> [0: bb3, 1: bb5, otherwise: bb7];
    }
--- a/tests/mir-opt/pre-codegen/slice_filter.variant_a-{closure#0}.PreCodegen.after.mir
+++ b/tests/mir-opt/pre-codegen/slice_filter.variant_a-{closure#0}.PreCodegen.after.mir
@ -32,7 +32,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
            debug other => _10;
            scope 3 (inlined std::cmp::impls::<impl PartialOrd for usize>::le) {
                debug self => _4;
-                debug other => _9;
+                debug other => _6;
                let mut _11: usize;
                let mut _12: usize;
            }
@ -42,7 +42,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
            debug other => _16;
            scope 5 (inlined std::cmp::impls::<impl PartialOrd for usize>::le) {
                debug self => _7;
-                debug other => _15;
+                debug other => _5;
                let mut _17: usize;
                let mut _18: usize;
            }
@ -52,7 +52,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
            debug other => _22;
            scope 7 (inlined std::cmp::impls::<impl PartialOrd for usize>::le) {
                debug self => _6;
-                debug other => _21;
+                debug other => _4;
            }
        }
        scope 8 (inlined std::cmp::impls::<impl PartialOrd for &usize>::le) {
@ -60,7 +60,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
            debug other => _26;
            scope 9 (inlined std::cmp::impls::<impl PartialOrd for usize>::le) {
                debug self => _5;
-                debug other => _25;
+                debug other => _7;
                let mut _27: usize;
                let mut _28: usize;
            }
@ -77,7 +77,8 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
        StorageLive(_8);
        _8 = &_4;
        StorageLive(_10);
-        _9 = &((*_3).2: usize);
+        StorageLive(_9);
+        _9 = _6;
        _10 = &_9;
        _11 = ((*_3).0: usize);
        _12 = ((*_3).2: usize);
@ -86,19 +87,22 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
    }

    bb1: {
+        StorageDead(_9);
        StorageDead(_10);
        StorageDead(_8);
        goto -> bb4;
    }

    bb2: {
+        StorageDead(_9);
        StorageDead(_10);
        StorageDead(_8);
        StorageLive(_19);
        StorageLive(_14);
        _14 = &_7;
        StorageLive(_16);
-        _15 = &((*_3).1: usize);
+        StorageLive(_15);
+        _15 = _5;
        _16 = &_15;
        StorageLive(_17);
        _17 = ((*_3).3: usize);
@ -111,6 +115,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
    }

    bb3: {
+        StorageDead(_15);
        StorageDead(_16);
        StorageDead(_14);
        goto -> bb4;
@ -121,13 +126,15 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
        StorageLive(_20);
        _20 = &_6;
        StorageLive(_22);
-        _21 = &((*_3).0: usize);
+        StorageLive(_21);
+        _21 = _4;
        _22 = &_21;
        _23 = Le(_12, _11);
        switchInt(move _23) -> [0: bb5, otherwise: bb6];
    }

    bb5: {
+        StorageDead(_21);
        StorageDead(_22);
        StorageDead(_20);
        _0 = const false;
@ -135,12 +142,14 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
    }

    bb6: {
+        StorageDead(_21);
        StorageDead(_22);
        StorageDead(_20);
        StorageLive(_24);
        _24 = &_5;
        StorageLive(_26);
-        _25 = &((*_3).3: usize);
+        StorageLive(_25);
+        _25 = _7;
        _26 = &_25;
        StorageLive(_27);
        _27 = ((*_3).1: usize);
@ -149,6 +158,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
        _0 = Le(move _27, move _28);
        StorageDead(_28);
        StorageDead(_27);
+        StorageDead(_25);
        StorageDead(_26);
        StorageDead(_24);
        goto -> bb7;
@ -160,6 +170,7 @@ fn variant_a::{closure#0}(_1: &mut {closure@$DIR/slice_filter.rs:7:25: 7:39}, _2
    }

    bb8: {
+        StorageDead(_15);
        StorageDead(_16);
        StorageDead(_14);
        _0 = const true;
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-abort.mir
@ -20,7 +20,7 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
    }

    bb0: {
-        StorageLive(_7);
+        StorageLive(_8);
        StorageLive(_4);
        StorageLive(_3);
        _3 = PtrMetadata(_1);
@ -36,7 +36,7 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {

    bb2: {
        StorageDead(_3);
-        StorageLive(_8);
+        StorageLive(_7);
        StorageLive(_5);
        _5 = &raw mut (*_1);
        StorageLive(_6);
@ -45,14 +45,14 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
        StorageDead(_6);
        StorageDead(_5);
        _8 = &mut (*_7);
-        _0 = Option::<&mut u32>::Some(move _8);
-        StorageDead(_8);
+        _0 = Option::<&mut u32>::Some(_8);
+        StorageDead(_7);
        goto -> bb3;
    }

    bb3: {
        StorageDead(_4);
-        StorageDead(_7);
+        StorageDead(_8);
        return;
    }
 }
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_mut_usize.PreCodegen.after.panic-unwind.mir
@ -20,7 +20,7 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
    }

    bb0: {
-        StorageLive(_7);
+        StorageLive(_8);
        StorageLive(_4);
        StorageLive(_3);
        _3 = PtrMetadata(_1);
@ -36,7 +36,7 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {

    bb2: {
        StorageDead(_3);
-        StorageLive(_8);
+        StorageLive(_7);
        StorageLive(_5);
        _5 = &raw mut (*_1);
        StorageLive(_6);
@ -45,14 +45,14 @@ fn slice_get_mut_usize(_1: &mut [u32], _2: usize) -> Option<&mut u32> {
        StorageDead(_6);
        StorageDead(_5);
        _8 = &mut (*_7);
-        _0 = Option::<&mut u32>::Some(move _8);
-        StorageDead(_8);
+        _0 = Option::<&mut u32>::Some(_8);
+        StorageDead(_7);
        goto -> bb3;
    }

    bb3: {
        StorageDead(_4);
-        StorageDead(_7);
+        StorageDead(_8);
        return;
    }
 }
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
@ -35,6 +35,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
    bb0: {
        _3 = move (_2.0: usize);
        _4 = move (_2.1: usize);
+        StorageLive(_11);
        StorageLive(_5);
        _5 = &raw mut (*_1);
        StorageLive(_8);
@ -56,6 +57,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
        StorageDead(_8);
        StorageDead(_5);
        _0 = &mut (*_11);
+        StorageDead(_11);
        return;
    }
 }
--- a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
@ -35,6 +35,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
    bb0: {
        _3 = move (_2.0: usize);
        _4 = move (_2.1: usize);
+        StorageLive(_11);
        StorageLive(_5);
        _5 = &raw mut (*_1);
        StorageLive(_8);
@ -56,6 +57,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
        StorageDead(_8);
        StorageDead(_5);
        _0 = &mut (*_11);
+        StorageDead(_11);
        return;
    }
 }
--- a/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir
@ -108,13 +108,11 @@ fn enumerated_loop(_1: &[T], _2: impl Fn(usize, &T)) -> () {

    bb4: {
        StorageLive(_15);
-        StorageLive(_14);
        _14 = &mut _13;
        _15 = <Enumerate<std::slice::Iter<'_, T>> as Iterator>::next(move _14) -> [return: bb5, unwind: bb11];
    }

    bb5: {
-        StorageDead(_14);
        _16 = discriminant(_15);
        switchInt(move _16) -> [0: bb6, 1: bb8, otherwise: bb10];
    }
--- a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir
@ -98,13 +98,11 @@ fn forward_loop(_1: &[T], _2: impl Fn(&T)) -> () {

    bb4: {
        StorageLive(_14);
-        StorageLive(_13);
        _13 = &mut _12;
        _14 = <std::slice::Iter<'_, T> as Iterator>::next(move _13) -> [return: bb5, unwind unreachable];
    }

    bb5: {
-        StorageDead(_13);
        _15 = discriminant(_14);
        switchInt(move _15) -> [0: bb6, 1: bb8, otherwise: bb10];
    }
--- a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir
@ -98,13 +98,11 @@ fn forward_loop(_1: &[T], _2: impl Fn(&T)) -> () {

    bb4: {
        StorageLive(_14);
-        StorageLive(_13);
        _13 = &mut _12;
        _14 = <std::slice::Iter<'_, T> as Iterator>::next(move _13) -> [return: bb5, unwind: bb11];
    }

    bb5: {
-        StorageDead(_13);
        _15 = discriminant(_14);
        switchInt(move _15) -> [0: bb6, 1: bb8, otherwise: bb10];
    }
--- a/tests/mir-opt/pre-codegen/spans.outer.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/spans.outer.PreCodegen.after.panic-abort.mir
@ -3,16 +3,14 @@
 fn outer(_1: u8) -> u8 {
    debug v => _1;                       // in scope 0 at $DIR/spans.rs:10:14: 10:15
    let mut _0: u8;                      // return place in scope 0 at $DIR/spans.rs:10:24: 10:26
-    let mut _2: &u8;                     // in scope 0 at $DIR/spans.rs:11:11: 11:13
+    let _2: &u8;                         // in scope 0 at $DIR/spans.rs:11:11: 11:13
    scope 1 (inlined inner) {            // at $DIR/spans.rs:11:5: 11:14
        debug x => _2;                   // in scope 1 at $DIR/spans.rs:14:14: 14:15
    }

    bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/spans.rs:11:11: 11:13
        _2 = &_1;                        // scope 0 at $DIR/spans.rs:11:11: 11:13
        _0 = _1;                         // scope 1 at $DIR/spans.rs:15:5: 15:7
-        StorageDead(_2);                 // scope 0 at $DIR/spans.rs:11:13: 11:14
        return;                          // scope 0 at $DIR/spans.rs:12:2: 12:2
    }
 }
--- a/tests/mir-opt/pre-codegen/spans.outer.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/spans.outer.PreCodegen.after.panic-unwind.mir
@ -3,16 +3,14 @@
 fn outer(_1: u8) -> u8 {
    debug v => _1;                       // in scope 0 at $DIR/spans.rs:10:14: 10:15
    let mut _0: u8;                      // return place in scope 0 at $DIR/spans.rs:10:24: 10:26
-    let mut _2: &u8;                     // in scope 0 at $DIR/spans.rs:11:11: 11:13
+    let _2: &u8;                         // in scope 0 at $DIR/spans.rs:11:11: 11:13
    scope 1 (inlined inner) {            // at $DIR/spans.rs:11:5: 11:14
        debug x => _2;                   // in scope 1 at $DIR/spans.rs:14:14: 14:15
    }

    bb0: {
-        StorageLive(_2);                 // scope 0 at $DIR/spans.rs:11:11: 11:13
        _2 = &_1;                        // scope 0 at $DIR/spans.rs:11:11: 11:13
        _0 = _1;                         // scope 1 at $DIR/spans.rs:15:5: 15:7
-        StorageDead(_2);                 // scope 0 at $DIR/spans.rs:11:13: 11:14
        return;                          // scope 0 at $DIR/spans.rs:12:2: 12:2
    }
 }
--- a/tests/mir-opt/pre-codegen/vec_deref.vec_deref_to_slice.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/vec_deref.vec_deref_to_slice.PreCodegen.after.panic-abort.mir
@ -56,10 +56,12 @@ fn vec_deref_to_slice(_1: &Vec<u8>) -> &[u8] {
        StorageDead(_2);
        StorageLive(_5);
        _5 = ((*_1).1: usize);
+        StorageLive(_6);
        _6 = *const [u8] from (_4, _5);
+        _0 = &(*_6);
+        StorageDead(_6);
        StorageDead(_5);
        StorageDead(_4);
-        _0 = &(*_6);
        return;
    }
 }
--- a/tests/mir-opt/pre-codegen/vec_deref.vec_deref_to_slice.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/vec_deref.vec_deref_to_slice.PreCodegen.after.panic-unwind.mir
@ -56,10 +56,12 @@ fn vec_deref_to_slice(_1: &Vec<u8>) -> &[u8] {
        StorageDead(_2);
        StorageLive(_5);
        _5 = ((*_1).1: usize);
+        StorageLive(_6);
        _6 = *const [u8] from (_4, _5);
+        _0 = &(*_6);
+        StorageDead(_6);
        StorageDead(_5);
        StorageDead(_4);
-        _0 = &(*_6);
        return;
    }
 }