58 lines
1.4 KiB
Rust
58 lines
1.4 KiB
Rust
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//@ known-bug: #116519
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#![allow(incomplete_features)]
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#![feature(generic_const_exprs)]
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trait Ret {
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type R;
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}
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struct Cond<const PRED: bool, U, V>(std::marker::PhantomData<U>, std::marker::PhantomData<V>);
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impl<U, V> Ret for Cond<true, U, V> {
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type R = U;
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}
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impl<U, V> Ret for Cond<false, U, V> {
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type R = V;
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}
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struct RobinHashTable<
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const MAX_LENGTH: usize,
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CellIdx = <Cond<{ MAX_LENGTH < 65535 }, u16, u32> as Ret>::R,
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> {
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_idx: CellIdx,
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}
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impl<CellIdx> RobinHashTable<MAX_LENGTH, CellIdx> {
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fn new() -> Self {
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Self {
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_idx: CellIdx { MAX_LENGTH },
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}
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}
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}
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impl<CellIdx> HashMapBase<CellIdx> {
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fn new() -> Self {
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Self {
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_idx: CellIdx { 0 },
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}
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}
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}
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impl<CellIdx> HashMapBase<CellIdx> for RobinHashTable<MAX_LENGTH, CellIdx> {
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fn hash<H: Hash + Hasher>(&self,
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) -> H {
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self._idx.hash()
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}
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fn eq(&self, other: &Self) -> bool {
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self._idx.eq(other._idx)
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}
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}
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impl<CellIdx> HashMapBase<CellIdx> for RobinHashTable<MAX_LENGTH, CellIdx> {
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fn hash<H: Hash + Hasher>(&self, other: &Self) -> H {
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self._idx.hash(other._idx)
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}
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fn eq(&self, other: &Self) -> bool {
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self._idx.eq(other._idx)
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}
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}
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#[test]
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fn test_size_of_robin_hash_table() {
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use std::mem::size_of;
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println!("{}", size_of::<RobinHashTable<1024>>());
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println!("{}", size_of::<RobinHashTable<65536>>());
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}
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