Rollup merge of rust-lang#60486 - spastorino:place-related-refactors,…

… r=oli-obk

Place related refactors

Meanwhile I was working on Place 2 I'm finding some little things that I had on my branch but preferred to land a separate PR for things that are simpler to merge.

r? @oli-obk

src/librustc/mir/mod.rs

@@ -2055,10 +2055,13 @@ impl<'tcx> Place<'tcx> {
 
     /// Finds the innermost `Local` from this `Place`.
     pub fn base_local(&self) -> Option<Local> {
-        match self {
-            Place::Base(PlaceBase::Local(local)) => Some(*local),
-            Place::Projection(box Projection { base, elem: _ }) => base.base_local(),
-            Place::Base(PlaceBase::Static(..)) => None,
+        let mut place = self;
+        loop {
+            match place {
+                Place::Projection(proj) => place = &proj.base,
+                Place::Base(PlaceBase::Static(_)) => return None,
+                Place::Base(PlaceBase::Local(local)) => return Some(*local),
+            }
         }
     }
 

src/librustc_mir/borrow_check/borrow_set.rs

@@ -210,7 +210,7 @@ impl<'a, 'gcx, 'tcx> Visitor<'tcx> for GatherBorrows<'a, 'gcx, 'tcx> {
 
             self.insert_as_pending_if_two_phase(location, &assigned_place, kind, idx);
 
-            if let Some(local) = borrowed_place.root_local() {
+            if let Some(local) = borrowed_place.base_local() {
                 self.local_map.entry(local).or_default().insert(idx);
             }
         }

src/librustc_mir/borrow_check/mod.rs

@@ -1831,7 +1831,6 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
                     }
 
                     place = base;
-                    continue;
                 }
             }
         }

src/librustc_mir/borrow_check/place_ext.rs

@@ -1,6 +1,6 @@
 use rustc::hir;
 use rustc::mir::ProjectionElem;
-use rustc::mir::{Local, Mir, Place, PlaceBase, Mutability, Static, StaticKind};
+use rustc::mir::{Mir, Place, PlaceBase, Mutability, Static, StaticKind};
 use rustc::ty::{self, TyCtxt};
 use crate::borrow_check::borrow_set::LocalsStateAtExit;
 
@@ -16,10 +16,6 @@ crate trait PlaceExt<'tcx> {
         mir: &Mir<'tcx>,
         locals_state_at_exit: &LocalsStateAtExit,
         ) -> bool;
-
-    /// If this is a place like `x.f.g`, returns the local
-    /// `x`. Returns `None` if this is based in a static.
-    fn root_local(&self) -> Option<Local>;
 }
 
 impl<'tcx> PlaceExt<'tcx> for Place<'tcx> {
@@ -82,15 +78,4 @@ impl<'tcx> PlaceExt<'tcx> for Place<'tcx> {
             },
         }
     }
-
-    fn root_local(&self) -> Option<Local> {
-        let mut p = self;
-        loop {
-            match p {
-                Place::Projection(pi) => p = &pi.base,
-                Place::Base(PlaceBase::Static(_)) => return None,
-                Place::Base(PlaceBase::Local(l)) => return Some(*l),
-            }
-        }
-    }
 }