Rollup merge of #92203 - Aaron1011:mir-adt-def, r=oli-obk

Store a `DefId` instead of an `AdtDef` in `AggregateKind::Adt`

The `AggregateKind` enum ends up in the final mir `Body`. Currently,
any changes to `AdtDef` (regardless of how significant they are)
will legitimately cause the overall result of `optimized_mir` to change,
invalidating any codegen re-use involving that mir.

This will get worse once we start hashing the `Span` inside `FieldDef`
(which is itself contained in `AdtDef`).

To try to reduce these kinds of invalidations, this commit changes
`AggregateKind::Adt` to store just the `DefId`, instead of the full
`AdtDef`. This allows the result of `optimized_mir` to be unchanged
if the `AdtDef` changes in a way that doesn't actually affect any
of the MIR we build.

3 files changed, 4 insertions, 4 deletions

diff --git a/compiler/rustc_mir_transform/src/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs
index 2dda19badd7..a40c4d1c366 100644
--- a/compiler/rustc_mir_transform/src/check_unsafety.rs
+++ b/compiler/rustc_mir_transform/src/check_unsafety.rs
@@ -117,8 +117,8 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> {
         match rvalue {
             Rvalue::Aggregate(box ref aggregate, _) => match aggregate {
                 &AggregateKind::Array(..) | &AggregateKind::Tuple => {}
-                &AggregateKind::Adt(ref def, ..) => {
-                    match self.tcx.layout_scalar_valid_range(def.did) {
+                &AggregateKind::Adt(adt_did, ..) => {
+                    match self.tcx.layout_scalar_valid_range(adt_did) {
                         (Bound::Unbounded, Bound::Unbounded) => {}
                         _ => self.require_unsafe(
                             UnsafetyViolationKind::General,
diff --git a/compiler/rustc_mir_transform/src/generator.rs b/compiler/rustc_mir_transform/src/generator.rs
index 6220cee8d21..bc9a104e849 100644
--- a/compiler/rustc_mir_transform/src/generator.rs
+++ b/compiler/rustc_mir_transform/src/generator.rs
@@ -243,7 +243,7 @@ impl<'tcx> TransformVisitor<'tcx> {
         val: Operand<'tcx>,
         source_info: SourceInfo,
     ) -> impl Iterator<Item = Statement<'tcx>> {
-        let kind = AggregateKind::Adt(self.state_adt_ref, idx, self.state_substs, None, None);
+        let kind = AggregateKind::Adt(self.state_adt_ref.did, idx, self.state_substs, None, None);
         assert_eq!(self.state_adt_ref.variants[idx].fields.len(), 1);
         let ty = self
             .tcx
diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs
index d0039380361..58996dcd673 100644
--- a/compiler/rustc_mir_transform/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@@ -777,7 +777,7 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> {
         adt_def.variants[variant_index].fields.iter().enumerate().map(|(idx, field_def)| {
             (Operand::Move(Place::from(Local::new(idx + 1))), field_def.ty(tcx, substs))
         }),
-        AggregateKind::Adt(adt_def, variant_index, substs, None, None),
+        AggregateKind::Adt(adt_def.did, variant_index, substs, None, None),
         source_info,
         tcx,
     )