mv compiler to compiler/

compiler/rustc_data_structures/src/stable_map.rs

@@ -0,0 +1,100 @@
+pub use rustc_hash::FxHashMap;
+use std::borrow::Borrow;
+use std::collections::hash_map::Entry;
+use std::fmt;
+use std::hash::Hash;
+
+/// A deterministic wrapper around FxHashMap that does not provide iteration support.
+///
+/// It supports insert, remove, get and get_mut functions from FxHashMap.
+/// It also allows to convert hashmap to a sorted vector with the method `into_sorted_vector()`.
+#[derive(Clone)]
+pub struct StableMap<K, V> {
+    base: FxHashMap<K, V>,
+}
+
+impl<K, V> Default for StableMap<K, V>
+where
+    K: Eq + Hash,
+{
+    fn default() -> StableMap<K, V> {
+        StableMap::new()
+    }
+}
+
+impl<K, V> fmt::Debug for StableMap<K, V>
+where
+    K: Eq + Hash + fmt::Debug,
+    V: fmt::Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{:?}", self.base)
+    }
+}
+
+impl<K, V> PartialEq for StableMap<K, V>
+where
+    K: Eq + Hash,
+    V: PartialEq,
+{
+    fn eq(&self, other: &StableMap<K, V>) -> bool {
+        self.base == other.base
+    }
+}
+
+impl<K, V> Eq for StableMap<K, V>
+where
+    K: Eq + Hash,
+    V: Eq,
+{
+}
+
+impl<K, V> StableMap<K, V>
+where
+    K: Eq + Hash,
+{
+    pub fn new() -> StableMap<K, V> {
+        StableMap { base: FxHashMap::default() }
+    }
+
+    pub fn into_sorted_vector(self) -> Vec<(K, V)>
+    where
+        K: Ord + Copy,
+    {
+        let mut vector = self.base.into_iter().collect::<Vec<_>>();
+        vector.sort_unstable_by_key(|pair| pair.0);
+        vector
+    }
+
+    pub fn entry(&mut self, k: K) -> Entry<'_, K, V> {
+        self.base.entry(k)
+    }
+
+    pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&V>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.base.get(k)
+    }
+
+    pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut V>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.base.get_mut(k)
+    }
+
+    pub fn insert(&mut self, k: K, v: V) -> Option<V> {
+        self.base.insert(k, v)
+    }
+
+    pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<V>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.base.remove(k)
+    }
+}