Struct rustc_data_structures::fx::FxHasher
source · pub struct FxHasher {
pub(crate) hash: usize,
}
Expand description
A speedy hash algorithm for use within rustc. 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 use a fast non-cryptographic hash.
This is the same as the algorithm used by Firefox – which is a homespun one not based on any widely-known algorithm – though modified to produce 64-bit hash values instead of 32-bit hash values. It consistently out-performs an FNV-based hash within rustc itself – the collision rate is similar or slightly worse than FNV, but the speed of the hash function itself is much higher because it works on up to 8 bytes at a time.
Fields§
§hash: usize
Auto Trait Implementations§
impl RefUnwindSafe for FxHasher
impl Send for FxHasher
impl Sync for FxHasher
impl Unpin for FxHasher
impl UnwindSafe for FxHasher
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
impl<'a, T> Captures<'a> for Twhere T: ?Sized,
Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 8 bytes