Rollup merge of #111410 - kylematsuda:earlybinder-abstract-const, r=BoxyUwU

Switch to `EarlyBinder` for `thir_abstract_const` query

Part of the work to finish https://github.com/rust-lang/rust/issues/105779.

This PR adds `EarlyBinder` to the return type of the `thir_abstract_const` query and removes `bound_abstract_const`.

r? `@compiler-errors`

compiler/rustc_infer/src/infer/mod.rs

@@ -1530,7 +1530,7 @@ impl<'tcx> InferCtxt<'tcx> {
         // variables
         let tcx = self.tcx;
         if substs.has_non_region_infer() {
-            if let Some(ct) = tcx.bound_abstract_const(unevaluated.def)? {
+            if let Some(ct) = tcx.thir_abstract_const(unevaluated.def)? {
                 let ct = tcx.expand_abstract_consts(ct.subst(tcx, substs));
                 if let Err(e) = ct.error_reported() {
                     return Err(ErrorHandled::Reported(e));

compiler/rustc_metadata/src/rmeta/mod.rs

@@ -394,7 +394,7 @@ define_tables! {
     mir_for_ctfe: Table<DefIndex, LazyValue<mir::Body<'static>>>,
     mir_generator_witnesses: Table<DefIndex, LazyValue<mir::GeneratorLayout<'static>>>,
     promoted_mir: Table<DefIndex, LazyValue<IndexVec<mir::Promoted, mir::Body<'static>>>>,
-    thir_abstract_const: Table<DefIndex, LazyValue<ty::Const<'static>>>,
+    thir_abstract_const: Table<DefIndex, LazyValue<ty::EarlyBinder<ty::Const<'static>>>>,
     impl_parent: Table<DefIndex, RawDefId>,
     impl_polarity: Table<DefIndex, ty::ImplPolarity>,
     constness: Table<DefIndex, hir::Constness>,

compiler/rustc_middle/src/query/erase.rs

@@ -82,9 +82,10 @@ impl EraseType for Result<Option<ty::Instance<'_>>, rustc_errors::ErrorGuarantee
         [u8; size_of::<Result<Option<ty::Instance<'static>>, rustc_errors::ErrorGuaranteed>>()];
 }
 
-impl EraseType for Result<Option<ty::Const<'_>>, rustc_errors::ErrorGuaranteed> {
+impl EraseType for Result<Option<ty::EarlyBinder<ty::Const<'_>>>, rustc_errors::ErrorGuaranteed> {
-    type Result =
+    type Result = [u8; size_of::<
-        [u8; size_of::<Result<Option<ty::Const<'static>>, rustc_errors::ErrorGuaranteed>>()];
+        Result<Option<ty::EarlyBinder<ty::Const<'static>>>, rustc_errors::ErrorGuaranteed>,
+    >()];
 }
 
 impl EraseType for Result<ty::GenericArg<'_>, traits::query::NoSolution> {

compiler/rustc_middle/src/query/mod.rs

@@ -402,7 +402,7 @@ rustc_queries! {
     /// Try to build an abstract representation of the given constant.
     query thir_abstract_const(
         key: DefId
-    ) -> Result<Option<ty::Const<'tcx>>, ErrorGuaranteed> {
+    ) -> Result<Option<ty::EarlyBinder<ty::Const<'tcx>>>, ErrorGuaranteed> {
         desc {
             |tcx| "building an abstract representation for `{}`", tcx.def_path_str(key),
         }

compiler/rustc_middle/src/ty/abstract_const.rs

@@ -4,7 +4,6 @@ use crate::ty::{
     TypeVisitableExt,
 };
 use rustc_errors::ErrorGuaranteed;
-use rustc_hir::def_id::DefId;
 
 #[derive(Hash, Debug, Clone, Copy, Ord, PartialOrd, PartialEq, Eq)]
 #[derive(TyDecodable, TyEncodable, HashStable, TypeVisitable, TypeFoldable)]
@@ -35,12 +34,6 @@ TrivialTypeTraversalAndLiftImpls! {
 pub type BoundAbstractConst<'tcx> = Result<Option<EarlyBinder<ty::Const<'tcx>>>, ErrorGuaranteed>;
 
 impl<'tcx> TyCtxt<'tcx> {
-    /// Returns a const without substs applied
-    pub fn bound_abstract_const(self, uv: DefId) -> BoundAbstractConst<'tcx> {
-        let ac = self.thir_abstract_const(uv);
-        Ok(ac?.map(|ac| EarlyBinder(ac)))
-    }
-
     pub fn expand_abstract_consts<T: TypeFoldable<TyCtxt<'tcx>>>(self, ac: T) -> T {
         struct Expander<'tcx> {
             tcx: TyCtxt<'tcx>,
@@ -59,7 +52,7 @@ impl<'tcx> TyCtxt<'tcx> {
             }
             fn fold_const(&mut self, c: Const<'tcx>) -> Const<'tcx> {
                 let ct = match c.kind() {
-                    ty::ConstKind::Unevaluated(uv) => match self.tcx.bound_abstract_const(uv.def) {
+                    ty::ConstKind::Unevaluated(uv) => match self.tcx.thir_abstract_const(uv.def) {
                         Err(e) => self.tcx.const_error_with_guaranteed(c.ty(), e),
                         Ok(Some(bac)) => {
                             let substs = self.tcx.erase_regions(uv.substs);

compiler/rustc_ty_utils/src/consts.rs

@@ -394,7 +394,7 @@ impl<'a, 'tcx> visit::Visitor<'a, 'tcx> for IsThirPolymorphic<'a, 'tcx> {
 pub fn thir_abstract_const(
     tcx: TyCtxt<'_>,
     def: LocalDefId,
-) -> Result<Option<ty::Const<'_>>, ErrorGuaranteed> {
+) -> Result<Option<ty::EarlyBinder<ty::Const<'_>>>, ErrorGuaranteed> {
     if !tcx.features().generic_const_exprs {
         return Ok(None);
     }
@@ -420,7 +420,7 @@ pub fn thir_abstract_const(
 
     let root_span = body.exprs[body_id].span;
 
-    Some(recurse_build(tcx, body, body_id, root_span)).transpose()
+    Ok(Some(ty::EarlyBinder(recurse_build(tcx, body, body_id, root_span)?)))
 }
 
 pub fn provide(providers: &mut ty::query::Providers) {