Uplift GenericArgKind, CanonicalVarValues, QueryInput, and NestedGoals

Author: compiler-errors

Cargo.lock

@@ -4343,6 +4343,7 @@ dependencies = [
  "rustc_hir_pretty",
  "rustc_index",
  "rustc_macros",
+ "rustc_next_trait_solver",
  "rustc_query_system",
  "rustc_serialize",
  "rustc_session",
@@ -4451,7 +4452,13 @@ dependencies = [
 name = "rustc_next_trait_solver"
 version = "0.0.0"
 dependencies = [
+ "derivative",
+ "rustc_ast_ir",
+ "rustc_data_structures",
+ "rustc_macros",
+ "rustc_serialize",
  "rustc_type_ir",
+ "rustc_type_ir_macros",
 ]
 
 [[package]]

compiler/rustc_infer/src/infer/at.rs

@@ -385,19 +385,31 @@ impl<'tcx> ToTrace<'tcx> for ty::GenericArg<'tcx> {
         a: Self,
         b: Self,
     ) -> TypeTrace<'tcx> {
-        use GenericArgKind::*;
         TypeTrace {
             cause: cause.clone(),
             values: match (a.unpack(), b.unpack()) {
-                (Lifetime(a), Lifetime(b)) => Regions(ExpectedFound::new(a_is_expected, a, b)),
-                (Type(a), Type(b)) => Terms(ExpectedFound::new(a_is_expected, a.into(), b.into())),
-                (Const(a), Const(b)) => {
+                (GenericArgKind::Lifetime(a), GenericArgKind::Lifetime(b)) => {
+                    Regions(ExpectedFound::new(a_is_expected, a, b))
+                }
+                (GenericArgKind::Type(a), GenericArgKind::Type(b)) => {
+                    Terms(ExpectedFound::new(a_is_expected, a.into(), b.into()))
+                }
+                (GenericArgKind::Const(a), GenericArgKind::Const(b)) => {
                     Terms(ExpectedFound::new(a_is_expected, a.into(), b.into()))
                 }
 
-                (Lifetime(_), Type(_) | Const(_))
-                | (Type(_), Lifetime(_) | Const(_))
-                | (Const(_), Lifetime(_) | Type(_)) => {
+                (
+                    GenericArgKind::Lifetime(_),
+                    GenericArgKind::Type(_) | GenericArgKind::Const(_),
+                )
+                | (
+                    GenericArgKind::Type(_),
+                    GenericArgKind::Lifetime(_) | GenericArgKind::Const(_),
+                )
+                | (
+                    GenericArgKind::Const(_),
+                    GenericArgKind::Lifetime(_) | GenericArgKind::Type(_),
+                ) => {
                     bug!("relating different kinds: {a:?} {b:?}")
                 }
             },

compiler/rustc_infer/src/traits/mod.rs

@@ -78,9 +78,9 @@ impl<T: Hash> Hash for Obligation<'_, T> {
     }
 }
 
-impl<'tcx, P> From<Obligation<'tcx, P>> for ty::Goal<'tcx, P> {
+impl<'tcx, P> From<Obligation<'tcx, P>> for solve::Goal<'tcx, P> {
     fn from(value: Obligation<'tcx, P>) -> Self {
-        ty::Goal { param_env: value.param_env, predicate: value.predicate }
+        solve::Goal { param_env: value.param_env, predicate: value.predicate }
     }
 }
 

compiler/rustc_middle/Cargo.toml

@@ -28,6 +28,7 @@ rustc_hir = { path = "../rustc_hir" }
 rustc_hir_pretty = { path = "../rustc_hir_pretty" }
 rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
+rustc_next_trait_solver = { path = "../rustc_next_trait_solver" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }

compiler/rustc_middle/src/infer/canonical.rs

@@ -23,23 +23,20 @@
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lock;
-use rustc_macros::{HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable};
-use rustc_type_ir::Canonical as IrCanonical;
-use rustc_type_ir::CanonicalVarInfo as IrCanonicalVarInfo;
+use rustc_macros::{HashStable, TypeFoldable, TypeVisitable};
+pub use rustc_type_ir as ir;
 pub use rustc_type_ir::{CanonicalTyVarKind, CanonicalVarKind};
 use smallvec::SmallVec;
 use std::collections::hash_map::Entry;
-use std::ops::Index;
 
 use crate::infer::MemberConstraint;
 use crate::mir::ConstraintCategory;
 use crate::ty::GenericArg;
-use crate::ty::{self, BoundVar, List, Region, Ty, TyCtxt, TypeFlags, TypeVisitableExt};
-
-pub type Canonical<'tcx, V> = IrCanonical<TyCtxt<'tcx>, V>;
-
-pub type CanonicalVarInfo<'tcx> = IrCanonicalVarInfo<TyCtxt<'tcx>>;
+use crate::ty::{self, List, Region, Ty, TyCtxt, TypeFlags, TypeVisitableExt};
 
+pub type Canonical<'tcx, V> = ir::Canonical<TyCtxt<'tcx>, V>;
+pub type CanonicalVarInfo<'tcx> = ir::CanonicalVarInfo<TyCtxt<'tcx>>;
+pub type CanonicalVarValues<'tcx> = ir::CanonicalVarValues<TyCtxt<'tcx>>;
 pub type CanonicalVarInfos<'tcx> = &'tcx List<CanonicalVarInfo<'tcx>>;
 
 impl<'tcx> ty::TypeFoldable<TyCtxt<'tcx>> for CanonicalVarInfos<'tcx> {
@@ -51,74 +48,6 @@ impl<'tcx> ty::TypeFoldable<TyCtxt<'tcx>> for CanonicalVarInfos<'tcx> {
     }
 }
 
-/// A set of values corresponding to the canonical variables from some
-/// `Canonical`. You can give these values to
-/// `canonical_value.instantiate` to instantiate them into the canonical
-/// value at the right places.
-///
-/// When you canonicalize a value `V`, you get back one of these
-/// vectors with the original values that were replaced by canonical
-/// variables. You will need to supply it later to instantiate the
-/// canonicalized query response.
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TyDecodable, TyEncodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable)]
-pub struct CanonicalVarValues<'tcx> {
-    pub var_values: ty::GenericArgsRef<'tcx>,
-}
-
-impl CanonicalVarValues<'_> {
-    pub fn is_identity(&self) -> bool {
-        self.var_values.iter().enumerate().all(|(bv, arg)| match arg.unpack() {
-            ty::GenericArgKind::Lifetime(r) => {
-                matches!(*r, ty::ReBound(ty::INNERMOST, br) if br.var.as_usize() == bv)
-            }
-            ty::GenericArgKind::Type(ty) => {
-                matches!(*ty.kind(), ty::Bound(ty::INNERMOST, bt) if bt.var.as_usize() == bv)
-            }
-            ty::GenericArgKind::Const(ct) => {
-                matches!(ct.kind(), ty::ConstKind::Bound(ty::INNERMOST, bc) if bc.as_usize() == bv)
-            }
-        })
-    }
-
-    pub fn is_identity_modulo_regions(&self) -> bool {
-        let mut var = ty::BoundVar::ZERO;
-        for arg in self.var_values {
-            match arg.unpack() {
-                ty::GenericArgKind::Lifetime(r) => {
-                    if let ty::ReBound(ty::INNERMOST, br) = *r
-                        && var == br.var
-                    {
-                        var = var + 1;
-                    } else {
-                        // It's ok if this region var isn't unique
-                    }
-                }
-                ty::GenericArgKind::Type(ty) => {
-                    if let ty::Bound(ty::INNERMOST, bt) = *ty.kind()
-                        && var == bt.var
-                    {
-                        var = var + 1;
-                    } else {
-                        return false;
-                    }
-                }
-                ty::GenericArgKind::Const(ct) => {
-                    if let ty::ConstKind::Bound(ty::INNERMOST, bc) = ct.kind()
-                        && var == bc
-                    {
-                        var = var + 1;
-                    } else {
-                        return false;
-                    }
-                }
-            }
-        }
-
-        true
-    }
-}
-
 /// When we canonicalize a value to form a query, we wind up replacing
 /// various parts of it with canonical variables. This struct stores
 /// those replaced bits to remember for when we process the query
@@ -218,78 +147,6 @@ TrivialTypeTraversalImpls! {
     crate::infer::canonical::Certainty,
 }
 
-impl<'tcx> CanonicalVarValues<'tcx> {
-    // Given a list of canonical variables, construct a set of values which are
-    // the identity response.
-    pub fn make_identity(
-        tcx: TyCtxt<'tcx>,
-        infos: CanonicalVarInfos<'tcx>,
-    ) -> CanonicalVarValues<'tcx> {
-        CanonicalVarValues {
-            var_values: tcx.mk_args_from_iter(infos.iter().enumerate().map(
-                |(i, info)| -> ty::GenericArg<'tcx> {
-                    match info.kind {
-                        CanonicalVarKind::Ty(_) | CanonicalVarKind::PlaceholderTy(_) => {
-                            Ty::new_bound(tcx, ty::INNERMOST, ty::BoundVar::from_usize(i).into())
-                                .into()
-                        }
-                        CanonicalVarKind::Region(_) | CanonicalVarKind::PlaceholderRegion(_) => {
-                            let br = ty::BoundRegion {
-                                var: ty::BoundVar::from_usize(i),
-                                kind: ty::BrAnon,
-                            };
-                            ty::Region::new_bound(tcx, ty::INNERMOST, br).into()
-                        }
-                        CanonicalVarKind::Effect => ty::Const::new_bound(
-                            tcx,
-                            ty::INNERMOST,
-                            ty::BoundVar::from_usize(i),
-                            tcx.types.bool,
-                        )
-                        .into(),
-                        CanonicalVarKind::Const(_, ty)
-                        | CanonicalVarKind::PlaceholderConst(_, ty) => ty::Const::new_bound(
-                            tcx,
-                            ty::INNERMOST,
-                            ty::BoundVar::from_usize(i),
-                            ty,
-                        )
-                        .into(),
-                    }
-                },
-            )),
-        }
-    }
-
-    /// Creates dummy var values which should not be used in a
-    /// canonical response.
-    pub fn dummy() -> CanonicalVarValues<'tcx> {
-        CanonicalVarValues { var_values: ty::List::empty() }
-    }
-
-    #[inline]
-    pub fn len(&self) -> usize {
-        self.var_values.len()
-    }
-}
-
-impl<'a, 'tcx> IntoIterator for &'a CanonicalVarValues<'tcx> {
-    type Item = GenericArg<'tcx>;
-    type IntoIter = ::std::iter::Copied<::std::slice::Iter<'a, GenericArg<'tcx>>>;
-
-    fn into_iter(self) -> Self::IntoIter {
-        self.var_values.iter()
-    }
-}
-
-impl<'tcx> Index<BoundVar> for CanonicalVarValues<'tcx> {
-    type Output = GenericArg<'tcx>;
-
-    fn index(&self, value: BoundVar) -> &GenericArg<'tcx> {
-        &self.var_values[value.as_usize()]
-    }
-}
-
 #[derive(Default)]
 pub struct CanonicalParamEnvCache<'tcx> {
     map: Lock<

compiler/rustc_middle/src/traits/solve.rs

@@ -1,6 +1,8 @@
 use rustc_ast_ir::try_visit;
 use rustc_data_structures::intern::Interned;
 use rustc_macros::{HashStable, TypeFoldable, TypeVisitable};
+use rustc_next_trait_solver::solve as ir_solve;
+pub use rustc_next_trait_solver::solve::*;
 use rustc_span::def_id::DefId;
 
 use crate::infer::canonical::{CanonicalVarValues, QueryRegionConstraints};
@@ -9,8 +11,6 @@ use crate::traits::Canonical;
 use crate::ty::{
     self, FallibleTypeFolder, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeVisitable, TypeVisitor,
 };
-// FIXME(compiler-errors): remove this import in favor of `use rustc_middle::ty::Goal`.
-pub use crate::ty::Goal;
 
 use super::BuiltinImplSource;
 
@@ -19,6 +19,9 @@ pub mod inspect;
 
 pub use cache::{CacheData, EvaluationCache};
 
+pub type Goal<'tcx, P> = ir_solve::Goal<TyCtxt<'tcx>, P>;
+pub type QueryInput<'tcx, P> = ir_solve::QueryInput<TyCtxt<'tcx>, P>;
+
 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, HashStable, TypeFoldable, TypeVisitable)]
 pub struct Response<'tcx> {
     pub certainty: Certainty,
@@ -87,12 +90,6 @@ impl MaybeCause {
     }
 }
 
-#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, HashStable, TypeFoldable, TypeVisitable)]
-pub struct QueryInput<'tcx, T> {
-    pub goal: Goal<'tcx, T>,
-    pub predefined_opaques_in_body: PredefinedOpaques<'tcx>,
-}
-
 /// Additional constraints returned on success.
 #[derive(Debug, PartialEq, Eq, Clone, Hash, HashStable, Default)]
 pub struct PredefinedOpaquesData<'tcx> {
@@ -229,29 +226,6 @@ impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for PredefinedOpaques<'tcx> {
     }
 }
 
-/// Why a specific goal has to be proven.
-///
-/// This is necessary as we treat nested goals different depending on
-/// their source.
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TypeVisitable, TypeFoldable)]
-pub enum GoalSource {
-    Misc,
-    /// We're proving a where-bound of an impl.
-    ///
-    /// FIXME(-Znext-solver=coinductive): Explain how and why this
-    /// changes whether cycles are coinductive.
-    ///
-    /// This also impacts whether we erase constraints on overflow.
-    /// Erasing constraints is generally very useful for perf and also
-    /// results in better error messages by avoiding spurious errors.
-    /// We do not erase overflow constraints in `normalizes-to` goals unless
-    /// they are from an impl where-clause. This is necessary due to
-    /// backwards compatability, cc trait-system-refactor-initiatitive#70.
-    ImplWhereBound,
-    /// Instantiating a higher-ranked goal and re-proving it.
-    InstantiateHigherRanked,
-}
-
 /// Possible ways the given goal can be proven.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum CandidateSource {

compiler/rustc_middle/src/ty/context.rs

@@ -90,6 +90,7 @@ use std::ops::{Bound, Deref};
 impl<'tcx> Interner for TyCtxt<'tcx> {
     type DefId = DefId;
     type DefiningOpaqueTypes = &'tcx ty::List<LocalDefId>;
+    type PredefinedOpaques = solve::PredefinedOpaques<'tcx>;
     type AdtDef = ty::AdtDef<'tcx>;
     type GenericArgs = ty::GenericArgsRef<'tcx>;
     type OwnItemArgs = &'tcx [ty::GenericArg<'tcx>];

compiler/rustc_middle/src/ty/generic_args.rs

@@ -11,6 +11,7 @@ use rustc_ast_ir::walk_visitable_list;
 use rustc_data_structures::intern::Interned;
 use rustc_errors::{DiagArgValue, IntoDiagArg};
 use rustc_hir::def_id::DefId;
+use rustc_macros::extension;
 use rustc_macros::{
     Decodable, Encodable, HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable,
 };
@@ -25,6 +26,8 @@ use std::num::NonZero;
 use std::ops::Deref;
 use std::ptr::NonNull;
 
+pub type GenericArgKind<'tcx> = rustc_type_ir::GenericArgKind<TyCtxt<'tcx>>;
+
 /// An entity in the Rust type system, which can be one of
 /// several kinds (types, lifetimes, and consts).
 /// To reduce memory usage, a `GenericArg` is an interned pointer,
@@ -49,6 +52,14 @@ impl<'tcx> rustc_type_ir::inherent::GenericArgs<TyCtxt<'tcx>> for ty::GenericArg
     }
 }
 
+impl<'tcx> rustc_type_ir::inherent::IntoKind for GenericArg<'tcx> {
+    type Kind = GenericArgKind<'tcx>;
+
+    fn kind(self) -> Self::Kind {
+        self.unpack()
+    }
+}
+
 #[cfg(parallel_compiler)]
 unsafe impl<'tcx> rustc_data_structures::sync::DynSend for GenericArg<'tcx> where
     &'tcx (Ty<'tcx>, ty::Region<'tcx>, ty::Const<'tcx>): rustc_data_structures::sync::DynSend
@@ -79,13 +90,7 @@ const TYPE_TAG: usize = 0b00;
 const REGION_TAG: usize = 0b01;
 const CONST_TAG: usize = 0b10;
 
-#[derive(Debug, TyEncodable, TyDecodable, PartialEq, Eq, HashStable)]
-pub enum GenericArgKind<'tcx> {
-    Lifetime(ty::Region<'tcx>),
-    Type(Ty<'tcx>),
-    Const(ty::Const<'tcx>),
-}
-
+#[extension(trait GenericArgPackExt<'tcx>)]
 impl<'tcx> GenericArgKind<'tcx> {
     #[inline]
     fn pack(self) -> GenericArg<'tcx> {