Remove PlaceBase enum and make Place base field be local: Local

5 files changed, 35 insertions, 86 deletions

diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index 05bb1d96980..32d85314c7a 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -1655,7 +1655,7 @@ impl Debug for Statement<'_> {
 /// changing or disturbing program state.
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, HashStable)]
 pub struct Place<'tcx> {
-    pub base: PlaceBase,
+    pub local: Local,
 
     /// projection out of a place (access a field, deref a pointer, etc)
     pub projection: &'tcx List<PlaceElem<'tcx>>,
@@ -1663,12 +1663,6 @@ pub struct Place<'tcx> {
 
 impl<'tcx> rustc_serialize::UseSpecializedDecodable for Place<'tcx> {}
 
-#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable, HashStable)]
-pub enum PlaceBase {
-    /// local variable
-    Local(Local),
-}
-
 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[derive(RustcEncodable, RustcDecodable, HashStable)]
 pub enum ProjectionElem<V, T> {
@@ -1756,14 +1750,14 @@ rustc_index::newtype_index! {
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct PlaceRef<'a, 'tcx> {
-    pub base: &'a PlaceBase,
+    pub local: &'a Local,
     pub projection: &'a [PlaceElem<'tcx>],
 }
 
 impl<'tcx> Place<'tcx> {
     // FIXME change this to a const fn by also making List::empty a const fn.
     pub fn return_place() -> Place<'tcx> {
-        Place { base: PlaceBase::Local(RETURN_PLACE), projection: List::empty() }
+        Place { local: RETURN_PLACE, projection: List::empty() }
     }
 
     /// Returns `true` if this `Place` contains a `Deref` projection.
@@ -1780,10 +1774,8 @@ impl<'tcx> Place<'tcx> {
     // FIXME: can we safely swap the semantics of `fn base_local` below in here instead?
     pub fn local_or_deref_local(&self) -> Option<Local> {
         match self.as_ref() {
-            PlaceRef { base: &PlaceBase::Local(local), projection: &[] }
-            | PlaceRef { base: &PlaceBase::Local(local), projection: &[ProjectionElem::Deref] } => {
-                Some(local)
-            }
+            PlaceRef { local, projection: &[] }
+            | PlaceRef { local, projection: &[ProjectionElem::Deref] } => Some(*local),
             _ => None,
         }
     }
@@ -1795,19 +1787,13 @@ impl<'tcx> Place<'tcx> {
     }
 
     pub fn as_ref(&self) -> PlaceRef<'_, 'tcx> {
-        PlaceRef { base: &self.base, projection: &self.projection }
+        PlaceRef { local: &self.local, projection: &self.projection }
     }
 }
 
 impl From<Local> for Place<'_> {
     fn from(local: Local) -> Self {
-        Place { base: local.into(), projection: List::empty() }
-    }
-}
-
-impl From<Local> for PlaceBase {
-    fn from(local: Local) -> Self {
-        PlaceBase::Local(local)
+        Place { local: local.into(), projection: List::empty() }
     }
 }
 
@@ -1818,10 +1804,8 @@ impl<'a, 'tcx> PlaceRef<'a, 'tcx> {
     // FIXME: can we safely swap the semantics of `fn base_local` below in here instead?
     pub fn local_or_deref_local(&self) -> Option<Local> {
         match self {
-            PlaceRef { base: PlaceBase::Local(local), projection: [] }
-            | PlaceRef { base: PlaceBase::Local(local), projection: [ProjectionElem::Deref] } => {
-                Some(*local)
-            }
+            PlaceRef { local, projection: [] }
+            | PlaceRef { local, projection: [ProjectionElem::Deref] } => Some(**local),
             _ => None,
         }
     }
@@ -1830,7 +1814,7 @@ impl<'a, 'tcx> PlaceRef<'a, 'tcx> {
     /// projections, return `Some(_X)`.
     pub fn as_local(&self) -> Option<Local> {
         match self {
-            PlaceRef { base: PlaceBase::Local(l), projection: [] } => Some(*l),
+            PlaceRef { local, projection: [] } => Some(**local),
             _ => None,
         }
     }
@@ -1852,7 +1836,7 @@ impl Debug for Place<'_> {
             }
         }
 
-        write!(fmt, "{:?}", self.base)?;
+        write!(fmt, "{:?}", self.local)?;
 
         for elem in self.projection.iter() {
             match elem {
@@ -1896,14 +1880,6 @@ impl Debug for Place<'_> {
     }
 }
 
-impl Debug for PlaceBase {
-    fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
-        match *self {
-            PlaceBase::Local(id) => write!(fmt, "{:?}", id),
-        }
-    }
-}
-
 ///////////////////////////////////////////////////////////////////////////
 // Scopes
 
@@ -2964,25 +2940,11 @@ impl<'tcx> TypeFoldable<'tcx> for GeneratorKind {
 
 impl<'tcx> TypeFoldable<'tcx> for Place<'tcx> {
     fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
-        Place { base: self.base.fold_with(folder), projection: self.projection.fold_with(folder) }
+        Place { local: self.local.fold_with(folder), projection: self.projection.fold_with(folder) }
     }
 
     fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
-        self.base.visit_with(visitor) || self.projection.visit_with(visitor)
-    }
-}
-
-impl<'tcx> TypeFoldable<'tcx> for PlaceBase {
-    fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
-        match self {
-            PlaceBase::Local(local) => PlaceBase::Local(local.fold_with(folder)),
-        }
-    }
-
-    fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
-        match self {
-            PlaceBase::Local(local) => local.visit_with(visitor),
-        }
+        self.local.visit_with(visitor) || self.projection.visit_with(visitor)
     }
 }
 
diff --git a/src/librustc/mir/tcx.rs b/src/librustc/mir/tcx.rs
index 5adf6447d39..e2aac562cc4 100644
--- a/src/librustc/mir/tcx.rs
+++ b/src/librustc/mir/tcx.rs
@@ -114,7 +114,7 @@ impl<'tcx> PlaceTy<'tcx> {
 
 impl<'tcx> Place<'tcx> {
     pub fn ty_from<D>(
-        base: &PlaceBase,
+        local: &Local,
         projection: &[PlaceElem<'tcx>],
         local_decls: &D,
         tcx: TyCtxt<'tcx>,
@@ -124,25 +124,16 @@ impl<'tcx> Place<'tcx> {
     {
         projection
             .iter()
-            .fold(base.ty(local_decls), |place_ty, elem| place_ty.projection_ty(tcx, elem))
+            .fold(PlaceTy::from_ty(local_decls.local_decls()[*local].ty), |place_ty, elem| {
+                place_ty.projection_ty(tcx, elem)
+            })
     }
 
     pub fn ty<D>(&self, local_decls: &D, tcx: TyCtxt<'tcx>) -> PlaceTy<'tcx>
     where
         D: HasLocalDecls<'tcx>,
     {
-        Place::ty_from(&self.base, &self.projection, local_decls, tcx)
-    }
-}
-
-impl<'tcx> PlaceBase {
-    pub fn ty<D>(&self, local_decls: &D) -> PlaceTy<'tcx>
-    where
-        D: HasLocalDecls<'tcx>,
-    {
-        match self {
-            PlaceBase::Local(index) => PlaceTy::from_ty(local_decls.local_decls()[*index].ty),
-        }
+        Place::ty_from(&self.local, &self.projection, local_decls, tcx)
     }
 }
 
diff --git a/src/librustc/mir/visit.rs b/src/librustc/mir/visit.rs
index a31931c8a99..4c5db1b07d2 100644
--- a/src/librustc/mir/visit.rs
+++ b/src/librustc/mir/visit.rs
@@ -164,10 +164,10 @@ macro_rules! make_mir_visitor {
             }
 
             fn visit_place_base(&mut self,
-                                base: & $($mutability)? PlaceBase,
+                                local: & $($mutability)? Local,
                                 context: PlaceContext,
                                 location: Location) {
-                self.super_place_base(base, context, location);
+                self.super_place_base(local, context, location);
             }
 
             visit_place_fns!($($mutability)?);
@@ -705,14 +705,10 @@ macro_rules! make_mir_visitor {
             }
 
             fn super_place_base(&mut self,
-                                place_base: & $($mutability)? PlaceBase,
+                                local: & $($mutability)? Local,
                                 context: PlaceContext,
                                 location: Location) {
-                match place_base {
-                    PlaceBase::Local(local) => {
-                        self.visit_local(local, context, location);
-                    }
-                }
+                self.visit_local(local, context, location);
             }
 
             fn super_local_decl(&mut self,
@@ -845,7 +841,7 @@ macro_rules! visit_place_fns {
             context: PlaceContext,
             location: Location,
         ) {
-            self.visit_place_base(&mut place.base, context, location);
+            self.visit_place_base(&mut place.local, context, location);
 
             if let Some(new_projection) = self.process_projection(&place.projection) {
                 place.projection = self.tcx().intern_place_elems(&new_projection);
@@ -886,23 +882,23 @@ macro_rules! visit_place_fns {
     () => (
         fn visit_projection(
             &mut self,
-            base: &PlaceBase,
+            local: &Local,
             projection: &[PlaceElem<'tcx>],
             context: PlaceContext,
             location: Location,
         ) {
-            self.super_projection(base, projection, context, location);
+            self.super_projection(local, projection, context, location);
         }
 
         fn visit_projection_elem(
             &mut self,
-            base: &PlaceBase,
+            local: &Local,
             proj_base: &[PlaceElem<'tcx>],
             elem: &PlaceElem<'tcx>,
             context: PlaceContext,
             location: Location,
         ) {
-            self.super_projection_elem(base, proj_base, elem, context, location);
+            self.super_projection_elem(local, proj_base, elem, context, location);
         }
 
         fn super_place(
@@ -921,9 +917,9 @@ macro_rules! visit_place_fns {
                 };
             }
 
-            self.visit_place_base(&place.base, context, location);
+            self.visit_place_base(&place.local, context, location);
 
-            self.visit_projection(&place.base,
+            self.visit_projection(&place.local,
                                   &place.projection,
                                   context,
                                   location);
@@ -931,7 +927,7 @@ macro_rules! visit_place_fns {
 
         fn super_projection(
             &mut self,
-            base: &PlaceBase,
+            local: &Local,
             projection: &[PlaceElem<'tcx>],
             context: PlaceContext,
             location: Location,
@@ -939,13 +935,13 @@ macro_rules! visit_place_fns {
             let mut cursor = projection;
             while let [proj_base @ .., elem] = cursor {
                 cursor = proj_base;
-                self.visit_projection_elem(base, cursor, elem, context, location);
+                self.visit_projection_elem(local, cursor, elem, context, location);
             }
         }
 
         fn super_projection_elem(
             &mut self,
-            _base: &PlaceBase,
+            _local: &Local,
             _proj_base: &[PlaceElem<'tcx>],
             elem: &PlaceElem<'tcx>,
             _context: PlaceContext,
diff --git a/src/librustc/ty/codec.rs b/src/librustc/ty/codec.rs
index c691cb44f01..df1602b2ac4 100644
--- a/src/librustc/ty/codec.rs
+++ b/src/librustc/ty/codec.rs
@@ -226,11 +226,11 @@ pub fn decode_place<D>(decoder: &mut D) -> Result<mir::Place<'tcx>, D::Error>
 where
     D: TyDecoder<'tcx>,
 {
-    let base: mir::PlaceBase = Decodable::decode(decoder)?;
+    let local: mir::Local = Decodable::decode(decoder)?;
     let len = decoder.read_usize()?;
     let projection: &'tcx List<mir::PlaceElem<'tcx>> =
         decoder.tcx().mk_place_elems((0..len).map(|_| Decodable::decode(decoder)))?;
-    Ok(mir::Place { base, projection })
+    Ok(mir::Place { local, projection })
 }
 
 #[inline]
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index 17f5b98ab20..52a151439dc 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -2434,7 +2434,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let mut projection = place.projection.to_vec();
         projection.push(elem);
 
-        Place { base: place.base, projection: self.intern_place_elems(&projection) }
+        Place { local: place.local, projection: self.intern_place_elems(&projection) }
     }
 
     pub fn intern_existential_predicates(