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use std::hash::BuildHasherDefault;

use rustc_hash::FxHasher;

/// A fast hashmap with no hash DoS protection. This is used in
/// extremely hot code.
///
/// Wrapping FxHasher (the fastest hash algorithm in difftastic
/// benchmarks) in a hashbrown::HashMap rather than std HashMap is a
/// little faster, and it also allows us to use the entry_ref API
/// which is unavailable in stable Rust.
pub(crate) type DftHashMap<K, V> = hashbrown::HashMap<K, V, BuildHasherDefault<FxHasher>>;