Auto merge of #43616 - mbrubeck:fnv, r=michaelwoerister

Remove unused FnvHash code

None

src/librustc_data_structures/fnv.rs

@@ -1,66 +0,0 @@
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use std::collections::{HashMap, HashSet};
-use std::default::Default;
-use std::hash::{Hasher, Hash, BuildHasherDefault};
-
-pub type FnvHashMap<K, V> = HashMap<K, V, BuildHasherDefault<FnvHasher>>;
-pub type FnvHashSet<V> = HashSet<V, BuildHasherDefault<FnvHasher>>;
-
-#[allow(non_snake_case)]
-pub fn FnvHashMap<K: Hash + Eq, V>() -> FnvHashMap<K, V> {
-    HashMap::default()
-}
-
-#[allow(non_snake_case)]
-pub fn FnvHashSet<V: Hash + Eq>() -> FnvHashSet<V> {
-    HashSet::default()
-}
-
-/// A speedy hash algorithm for node ids and def ids. The hashmap in
-/// liballoc by default uses SipHash which isn't quite as speedy as we
-/// want. In the compiler we're not really worried about DOS attempts, so we
-/// just default to a non-cryptographic hash.
-///
-/// This uses FNV hashing, as described here:
-/// http://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function
-pub struct FnvHasher(u64);
-
-impl Default for FnvHasher {
-    /// Creates a `FnvHasher`, with a 64-bit hex initial value.
-    #[inline]
-    fn default() -> FnvHasher {
-        FnvHasher(0xcbf29ce484222325)
-    }
-}
-
-impl Hasher for FnvHasher {
-    #[inline]
-    fn write(&mut self, bytes: &[u8]) {
-        let FnvHasher(mut hash) = *self;
-        for byte in bytes {
-            hash = hash ^ (*byte as u64);
-            hash = hash.wrapping_mul(0x100000001b3);
-        }
-        *self = FnvHasher(hash);
-    }
-
-    #[inline]
-    fn finish(&self) -> u64 {
-        self.0
-    }
-}
-
-pub fn hash<T: Hash>(v: &T) -> u64 {
-    let mut state = FnvHasher::default();
-    v.hash(&mut state);
-    state.finish()
-}

src/librustc_data_structures/lib.rs

@@ -65,7 +65,6 @@ pub mod snapshot_vec;
 pub mod stable_hasher;
 pub mod transitive_relation;
 pub mod unify;
-pub mod fnv;
 pub mod fx;
 pub mod tuple_slice;
 pub mod veccell;