transition various normalization functions to the new methods

In particular:

- `fully_normalize_monormophic_ty` => `normalize_erasing_regions`
- `normalize_associated_type_in_env` => `normalize_erasing_regions`
- `fully_normalize_associated_types_in` => `normalize_erasing_regions`
- `erase_late_bound_regions_and_normalize` => `normalize_erasing_late_bound_regions`

Author: nikomatsakis

src/librustc/dep_graph/dep_node.rs

@@ -635,7 +635,6 @@ define_dep_nodes!( <'tcx>
     [] CodegenUnit(InternedString),
     [] CompileCodegenUnit(InternedString),
     [input] OutputFilenames,
-    [anon] NormalizeTy,
     [] NormalizeProjectionTy(CanonicalProjectionGoal<'tcx>),
     [] NormalizeTyAfterErasingRegions(ParamEnvAnd<'tcx, Ty<'tcx>>),
     [] DropckOutlives(CanonicalTyGoal<'tcx>),

src/librustc/infer/mod.rs

@@ -21,7 +21,6 @@ use hir::def_id::DefId;
 use middle::free_region::RegionRelations;
 use middle::region;
 use middle::lang_items;
-use mir::tcx::PlaceTy;
 use ty::subst::Substs;
 use ty::{TyVid, IntVid, FloatVid};
 use ty::{self, Ty, TyCtxt};
@@ -35,7 +34,7 @@ use std::collections::BTreeMap;
 use std::fmt;
 use syntax::ast;
 use errors::DiagnosticBuilder;
-use syntax_pos::{self, Span, DUMMY_SP};
+use syntax_pos::{self, Span};
 use util::nodemap::FxHashMap;
 use arena::DroplessArena;
 
@@ -493,140 +492,7 @@ pub struct CombinedSnapshot<'a, 'tcx:'a> {
     _in_progress_tables: Option<Ref<'a, ty::TypeckTables<'tcx>>>,
 }
 
-/// Helper trait for shortening the lifetimes inside a
-/// value for post-type-checking normalization.
-///
-/// This trait offers a normalization method where the inputs and
-/// outputs both have the `'gcx` lifetime; the implementations
-/// internally create inference contexts and/or lift as needed.
-pub trait TransNormalize<'gcx>: TypeFoldable<'gcx> {
-    fn trans_normalize<'a, 'tcx>(&self,
-                                 infcx: &InferCtxt<'a, 'gcx, 'tcx>,
-                                 param_env: ty::ParamEnv<'tcx>)
-                                 -> Self;
-}
-
-macro_rules! items { ($($item:item)+) => ($($item)+) }
-macro_rules! impl_trans_normalize {
-    ($lt_gcx:tt, $($ty:ty),+) => {
-        items!($(impl<$lt_gcx> TransNormalize<$lt_gcx> for $ty {
-            fn trans_normalize<'a, 'tcx>(&self,
-                                         infcx: &InferCtxt<'a, $lt_gcx, 'tcx>,
-                                         param_env: ty::ParamEnv<'tcx>)
-                                         -> Self {
-                infcx.normalize_projections_in(param_env, self)
-            }
-        })+);
-    }
-}
-
-impl_trans_normalize!('gcx,
-    Ty<'gcx>,
-    &'gcx ty::Const<'gcx>,
-    &'gcx Substs<'gcx>,
-    ty::FnSig<'gcx>,
-    ty::PolyFnSig<'gcx>,
-    ty::ClosureSubsts<'gcx>,
-    ty::PolyTraitRef<'gcx>,
-    ty::ExistentialTraitRef<'gcx>
-);
-
-impl<'gcx> TransNormalize<'gcx> for PlaceTy<'gcx> {
-    fn trans_normalize<'a, 'tcx>(&self,
-                                 infcx: &InferCtxt<'a, 'gcx, 'tcx>,
-                                 param_env: ty::ParamEnv<'tcx>)
-                                 -> Self {
-        match *self {
-            PlaceTy::Ty { ty } => PlaceTy::Ty { ty: ty.trans_normalize(infcx, param_env) },
-            PlaceTy::Downcast { adt_def, substs, variant_index } => {
-                PlaceTy::Downcast {
-                    adt_def,
-                    substs: substs.trans_normalize(infcx, param_env),
-                    variant_index,
-                }
-            }
-        }
-    }
-}
-
-// NOTE: Callable from trans only!
-impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
-    /// Currently, higher-ranked type bounds inhibit normalization. Therefore,
-    /// each time we erase them in translation, we need to normalize
-    /// the contents.
-    pub fn erase_late_bound_regions_and_normalize<T>(self, value: &ty::Binder<T>)
-        -> T
-        where T: TransNormalize<'tcx>
-    {
-        assert!(!value.needs_subst());
-        let value = self.erase_late_bound_regions(value);
-        self.fully_normalize_associated_types_in(&value)
-    }
-
-    /// Fully normalizes any associated types in `value`, using an
-    /// empty environment and `Reveal::All` mode (therefore, suitable
-    /// only for monomorphized code during trans, basically).
-    pub fn fully_normalize_associated_types_in<T>(self, value: &T) -> T
-        where T: TransNormalize<'tcx>
-    {
-        debug!("fully_normalize_associated_types_in(t={:?})", value);
-
-        let param_env = ty::ParamEnv::reveal_all();
-        let value = self.erase_regions(value);
-
-        if !value.has_projections() {
-            return value;
-        }
-
-        self.infer_ctxt().enter(|infcx| {
-            value.trans_normalize(&infcx, param_env)
-        })
-    }
-
-    /// Does a best-effort to normalize any associated types in
-    /// `value`; this includes revealing specializable types, so this
-    /// should be not be used during type-checking, but only during
-    /// optimization and code generation.
-    pub fn normalize_associated_type_in_env<T>(
-        self, value: &T, env: ty::ParamEnv<'tcx>
-    ) -> T
-        where T: TransNormalize<'tcx>
-    {
-        debug!("normalize_associated_type_in_env(t={:?})", value);
-
-        let value = self.erase_regions(value);
-
-        if !value.has_projections() {
-            return value;
-        }
-
-        self.infer_ctxt().enter(|infcx| {
-            value.trans_normalize(&infcx, env.with_reveal_all())
-       })
-    }
-}
-
 impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
-    fn normalize_projections_in<T>(&self, param_env: ty::ParamEnv<'tcx>, value: &T) -> T::Lifted
-        where T: TypeFoldable<'tcx> + ty::Lift<'gcx>
-    {
-        let mut selcx = traits::SelectionContext::new(self);
-        let cause = traits::ObligationCause::dummy();
-        let traits::Normalized { value: result, obligations } =
-            traits::normalize(&mut selcx, param_env, cause, value);
-
-        debug!("normalize_projections_in: result={:?} obligations={:?}",
-                result, obligations);
-
-        let mut fulfill_cx = traits::FulfillmentContext::new();
-
-        for obligation in obligations {
-            fulfill_cx.register_predicate_obligation(self, obligation);
-        }
-
-        self.drain_fulfillment_cx_or_panic(DUMMY_SP, &mut fulfill_cx, &result)
-    }
-
     /// Finishes processes any obligations that remain in the
     /// fulfillment context, and then returns the result with all type
     /// variables removed and regions erased. Because this is intended

src/librustc/traits/mod.rs

@@ -770,7 +770,10 @@ fn vtable_methods<'a, 'tcx>(
                 // the trait type may have higher-ranked lifetimes in it;
                 // so erase them if they appear, so that we get the type
                 // at some particular call site
-                let substs = tcx.erase_late_bound_regions_and_normalize(&ty::Binder(substs));
+                let substs = tcx.normalize_erasing_late_bound_regions(
+                    ty::ParamEnv::reveal_all(),
+                    &ty::Binder(substs),
+                );
 
                 // It's possible that the method relies on where clauses that
                 // do not hold for this particular set of type parameters.

src/librustc/traits/trans/mod.rs

@@ -14,14 +14,13 @@
 // general routines.
 
 use dep_graph::{DepKind, DepTrackingMapConfig};
-use infer::TransNormalize;
 use std::marker::PhantomData;
 use syntax_pos::DUMMY_SP;
 use hir::def_id::DefId;
 use traits::{FulfillmentContext, Obligation, ObligationCause, SelectionContext, Vtable};
 use ty::{self, Ty, TyCtxt};
 use ty::subst::{Subst, Substs};
-use ty::fold::{TypeFoldable, TypeFolder};
+use ty::fold::TypeFoldable;
 
 /// Attempts to resolve an obligation to a vtable.. The result is
 /// a shallow vtable resolution -- meaning that we do not
@@ -93,12 +92,11 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
                                        param_substs: &Substs<'tcx>,
                                        value: &T)
                                        -> T
-        where T: TransNormalize<'tcx>
+        where T: TypeFoldable<'tcx>
     {
         debug!("apply_param_substs(param_substs={:?}, value={:?})", param_substs, value);
         let substituted = value.subst(self, param_substs);
-        let substituted = self.erase_regions(&substituted);
-        AssociatedTypeNormalizer::new(self).fold(&substituted)
+        self.normalize_erasing_regions(ty::ParamEnv::reveal_all(), substituted)
     }
 
     pub fn trans_apply_param_substs_env<T>(
@@ -108,7 +106,7 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
         value: &T,
     ) -> T
     where
-        T: TransNormalize<'tcx>,
+        T: TypeFoldable<'tcx>,
     {
         debug!(
             "apply_param_substs_env(param_substs={:?}, value={:?}, param_env={:?})",
@@ -117,8 +115,7 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
             param_env,
         );
         let substituted = value.subst(self, param_substs);
-        let substituted = self.erase_regions(&substituted);
-        AssociatedTypeNormalizerEnv::new(self, param_env).fold(&substituted)
+        self.normalize_erasing_regions(param_env, substituted)
     }
 
     pub fn trans_impl_self_ty(&self, def_id: DefId, substs: &'tcx Substs<'tcx>)
@@ -128,73 +125,6 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
     }
 }
 
-struct AssociatedTypeNormalizer<'a, 'gcx: 'a> {
-    tcx: TyCtxt<'a, 'gcx, 'gcx>,
-}
-
-impl<'a, 'gcx> AssociatedTypeNormalizer<'a, 'gcx> {
-    fn new(tcx: TyCtxt<'a, 'gcx, 'gcx>) -> Self {
-        AssociatedTypeNormalizer { tcx }
-    }
-
-    fn fold<T:TypeFoldable<'gcx>>(&mut self, value: &T) -> T {
-        if !value.has_projections() {
-            value.clone()
-        } else {
-            value.fold_with(self)
-        }
-    }
-}
-
-impl<'a, 'gcx> TypeFolder<'gcx, 'gcx> for AssociatedTypeNormalizer<'a, 'gcx> {
-    fn tcx<'c>(&'c self) -> TyCtxt<'c, 'gcx, 'gcx> {
-        self.tcx
-    }
-
-    fn fold_ty(&mut self, ty: Ty<'gcx>) -> Ty<'gcx> {
-        if !ty.has_projections() {
-            ty
-        } else {
-            debug!("AssociatedTypeNormalizer: ty={:?}", ty);
-            self.tcx.fully_normalize_monormophic_ty(ty)
-        }
-    }
-}
-
-struct AssociatedTypeNormalizerEnv<'a, 'gcx: 'a> {
-    tcx: TyCtxt<'a, 'gcx, 'gcx>,
-    param_env: ty::ParamEnv<'gcx>,
-}
-
-impl<'a, 'gcx> AssociatedTypeNormalizerEnv<'a, 'gcx> {
-    fn new(tcx: TyCtxt<'a, 'gcx, 'gcx>, param_env: ty::ParamEnv<'gcx>) -> Self {
-        Self { tcx, param_env }
-    }
-
-    fn fold<T: TypeFoldable<'gcx>>(&mut self, value: &T) -> T {
-        if !value.has_projections() {
-            value.clone()
-        } else {
-            value.fold_with(self)
-        }
-    }
-}
-
-impl<'a, 'gcx> TypeFolder<'gcx, 'gcx> for AssociatedTypeNormalizerEnv<'a, 'gcx> {
-    fn tcx<'c>(&'c self) -> TyCtxt<'c, 'gcx, 'gcx> {
-        self.tcx
-    }
-
-    fn fold_ty(&mut self, ty: Ty<'gcx>) -> Ty<'gcx> {
-        if !ty.has_projections() {
-            ty
-        } else {
-            debug!("AssociatedTypeNormalizerEnv: ty={:?}", ty);
-            self.tcx.normalize_associated_type_in_env(&ty, self.param_env)
-        }
-    }
-}
-
 // Implement DepTrackingMapConfig for `trait_cache`
 pub struct TraitSelectionCache<'tcx> {
     data: PhantomData<&'tcx ()>

src/librustc/ty/context.rs

@@ -2537,9 +2537,6 @@ pub fn provide(providers: &mut ty::maps::Providers) {
         assert_eq!(cnum, LOCAL_CRATE);
         tcx.features().clone_closures
     };
-    providers.fully_normalize_monormophic_ty = |tcx, ty| {
-        tcx.fully_normalize_associated_types_in(&ty)
-    };
     providers.features_query = |tcx, cnum| {
         assert_eq!(cnum, LOCAL_CRATE);
         Lrc::new(tcx.sess.features_untracked().clone())

src/librustc/ty/instance.rs

@@ -352,7 +352,7 @@ fn fn_once_adapter_instance<'a, 'tcx>(
         closure_did, substs);
 
     let sig = substs.closure_sig(closure_did, tcx);
-    let sig = tcx.erase_late_bound_regions_and_normalize(&sig);
+    let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
     assert_eq!(sig.inputs().len(), 1);
     let substs = tcx.mk_substs([Kind::from(self_ty), sig.inputs()[0].into()].iter().cloned());
 

src/librustc/ty/layout.rs

@@ -1213,7 +1213,7 @@ impl<'a, 'tcx> LayoutCx<'tcx, TyCtxt<'a, 'tcx, 'tcx>> {
                     data_ptr.valid_range.start = 1;
                 }
 
-                let pointee = tcx.normalize_associated_type_in_env(&pointee, param_env);
+                let pointee = tcx.normalize_erasing_regions(param_env, pointee);
                 if pointee.is_sized(tcx.at(DUMMY_SP), param_env) {
                     return Ok(tcx.intern_layout(LayoutDetails::scalar(self, data_ptr)));
                 }
@@ -1241,7 +1241,7 @@ impl<'a, 'tcx> LayoutCx<'tcx, TyCtxt<'a, 'tcx, 'tcx>> {
             // Arrays and slices.
             ty::TyArray(element, mut count) => {
                 if count.has_projections() {
-                    count = tcx.normalize_associated_type_in_env(&count, param_env);
+                    count = tcx.normalize_erasing_regions(param_env, count);
                     if count.has_projections() {
                         return Err(LayoutError::Unknown(ty));
                     }
@@ -1686,7 +1686,7 @@ impl<'a, 'tcx> LayoutCx<'tcx, TyCtxt<'a, 'tcx, 'tcx>> {
 
             // Types with no meaningful known layout.
             ty::TyProjection(_) | ty::TyAnon(..) => {
-                let normalized = tcx.normalize_associated_type_in_env(&ty, param_env);
+                let normalized = tcx.normalize_erasing_regions(param_env, ty);
                 if ty == normalized {
                     return Err(LayoutError::Unknown(ty));
                 }
@@ -1953,7 +1953,7 @@ impl<'a, 'tcx> SizeSkeleton<'tcx> {
             }
 
             ty::TyProjection(_) | ty::TyAnon(..) => {
-                let normalized = tcx.normalize_associated_type_in_env(&ty, param_env);
+                let normalized = tcx.normalize_erasing_regions(param_env, ty);
                 if ty == normalized {
                     Err(err)
                 } else {
@@ -2059,7 +2059,7 @@ impl<'a, 'tcx> LayoutOf<Ty<'tcx>> for LayoutCx<'tcx, TyCtxt<'a, 'tcx, 'tcx>> {
     /// executes in "reveal all" mode.
     fn layout_of(self, ty: Ty<'tcx>) -> Self::TyLayout {
         let param_env = self.param_env.with_reveal_all();
-        let ty = self.tcx.normalize_associated_type_in_env(&ty, param_env);
+        let ty = self.tcx.normalize_erasing_regions(param_env, ty);
         let details = self.tcx.layout_raw(param_env.and(ty))?;
         let layout = TyLayout {
             ty,
@@ -2085,7 +2085,7 @@ impl<'a, 'tcx> LayoutOf<Ty<'tcx>> for LayoutCx<'tcx, ty::maps::TyCtxtAt<'a, 'tcx
     /// executes in "reveal all" mode.
     fn layout_of(self, ty: Ty<'tcx>) -> Self::TyLayout {
         let param_env = self.param_env.with_reveal_all();
-        let ty = self.tcx.normalize_associated_type_in_env(&ty, param_env);
+        let ty = self.tcx.normalize_erasing_regions(param_env, ty);
         let details = self.tcx.layout_raw(param_env.and(ty))?;
         let layout = TyLayout {
             ty,

src/librustc/ty/maps/config.rs

@@ -610,12 +610,6 @@ impl<'tcx> QueryDescription<'tcx> for queries::has_copy_closures<'tcx> {
     }
 }
 
-impl<'tcx> QueryDescription<'tcx> for queries::fully_normalize_monormophic_ty<'tcx> {
-    fn describe(_tcx: TyCtxt, _: Ty) -> String {
-        format!("normalizing types")
-    }
-}
-
 impl<'tcx> QueryDescription<'tcx> for queries::features_query<'tcx> {
     fn describe(_tcx: TyCtxt, _: CrateNum) -> String {
         format!("looking up enabled feature gates")