Kill placement_new

src/hash/map.rs

@@ -18,8 +18,7 @@ use fmt::{self, Debug};
 use hash::{Hash, BuildHasher};
 use iter::{FromIterator, FusedIterator};
 use mem::{self, replace};
-use ops::{Deref, Index, InPlace, Place, Placer};
-use ptr;
+use ops::{Deref, Index};
 
 use super::table::{self, Bucket, EmptyBucket, FullBucket, FullBucketMut, RawTable, SafeHash};
 use super::table::BucketState::{Empty, Full};
@@ -1777,61 +1776,7 @@ impl<'a, K, V> fmt::Debug for Drain<'a, K, V>
     }
 }
 
-/// A place for insertion to a `Entry`.
-///
-/// See [`HashMap::entry`](struct.HashMap.html#method.entry) for details.
-#[must_use = "places do nothing unless written to with `<-` syntax"]
-pub struct EntryPlace<'a, K: 'a, V: 'a> {
-    bucket: FullBucketMut<'a, K, V>,
-}
-
-impl<'a, K: 'a + Debug, V: 'a + Debug> Debug for EntryPlace<'a, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.debug_struct("EntryPlace")
-            .field("key", self.bucket.read().0)
-            .field("value", self.bucket.read().1)
-            .finish()
-    }
-}
-
-impl<'a, K, V> Drop for EntryPlace<'a, K, V> {
-    fn drop(&mut self) {
-        // Inplacement insertion failed. Only key need to drop.
-        // The value is failed to insert into map.
-        unsafe { self.bucket.remove_key() };
-    }
-}
-
-impl<'a, K, V> Placer<V> for Entry<'a, K, V> {
-    type Place = EntryPlace<'a, K, V>;
-
-    fn make_place(self) -> EntryPlace<'a, K, V> {
-        let b = match self {
-            Occupied(mut o) => {
-                unsafe { ptr::drop_in_place(o.elem.read_mut().1); }
-                o.elem
-            }
-            Vacant(v) => {
-                unsafe { v.insert_key() }
-            }
-        };
-        EntryPlace { bucket: b }
-    }
-}
-
-impl<'a, K, V> Place<V> for EntryPlace<'a, K, V> {
-    fn pointer(&mut self) -> *mut V {
-        self.bucket.read_mut().1
-    }
-}
-
-impl<'a, K, V> InPlace<V> for EntryPlace<'a, K, V> {
-    type Owner = ();
-
-    unsafe fn finalize(self) {
-        mem::forget(self);
-    }
-}
+// FORK NOTE: Removed Placer impl
 
 impl<'a, K, V> Entry<'a, K, V> {
         /// Ensures a value is in the entry by inserting the default if empty, and returns
@@ -2119,26 +2064,6 @@ impl<'a, K: 'a, V: 'a> VacantEntry<'a, K, V> {
         };
         b.into_mut_refs().1
     }
-
-    // Only used for InPlacement insert. Avoid unnecessary value copy.
-    // The value remains uninitialized.
-    unsafe fn insert_key(self) -> FullBucketMut<'a, K, V> {
-        match self.elem {
-            NeqElem(mut bucket, disp) => {
-                if disp >= DISPLACEMENT_THRESHOLD {
-                    bucket.table_mut().set_tag(true);
-                }
-                let uninit = mem::uninitialized();
-                robin_hood(bucket, disp, self.hash, self.key, uninit)
-            },
-            NoElem(mut bucket, disp) => {
-                if disp >= DISPLACEMENT_THRESHOLD {
-                    bucket.table_mut().set_tag(true);
-                }
-                bucket.put_key(self.hash, self.key)
-            },
-        }
-    }
 }
 
 impl<K, V, S> FromIterator<(K, V)> for HashMap<K, V, S>

src/hash/table.rs

@@ -487,21 +487,6 @@ impl<K, V, M> EmptyBucket<K, V, M>
             table: self.table,
         }
     }
-
-    /// Puts given key, remain value uninitialized.
-    /// It is only used for inplacement insertion.
-    pub unsafe fn put_key(mut self, hash: SafeHash, key: K) -> FullBucket<K, V, M> {
-        *self.raw.hash() = hash.inspect();
-        let pair_ptr = self.raw.pair();
-        ptr::write(&mut (*pair_ptr).0, key);
-
-        self.table.borrow_table_mut().size += 1;
-
-        FullBucket {
-            raw: self.raw,
-            table: self.table,
-        }
-    }
 }
 
 impl<K, V, M: Deref<Target = RawTable<K, V>>> FullBucket<K, V, M> {
@@ -577,17 +562,6 @@ impl<'t, K, V> FullBucket<K, V, &'t mut RawTable<K, V>> {
             v)
         }
     }
-
-    /// Remove this bucket's `key` from the hashtable.
-    /// Only used for inplacement insertion.
-    /// NOTE: `Value` is uninitialized when this function is called, don't try to drop the `Value`.
-    pub unsafe fn remove_key(&mut self) {
-        self.table.size -= 1;
-
-        *self.raw.hash() = EMPTY_BUCKET;
-        let pair_ptr = self.raw.pair();
-        ptr::drop_in_place(&mut (*pair_ptr).0); // only drop key
-    }
 }
 
 // This use of `Put` is misleading and restrictive, but safe and sufficient for our use cases

src/lib.rs

@@ -1,5 +1,5 @@
 #![feature(allocator_api)]
-#![feature(alloc, shared, unique, fused, placement_new_protocol)]
+#![feature(alloc, shared, unique, fused)]
 
 extern crate alloc;