Skip to content

Remove dead cache from IndexSet #262

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
fitzgen wants to merge 1 commit into
base: main
Choose a base branch
from
+1 −18
Open

Remove dead cache from IndexSet #262

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 1 addition & 18 deletions src/indexset.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,17 +6,13 @@
//! Index sets: sets of integers that represent indices into a space.

use alloc::vec::Vec;
use core::cell::Cell;

use crate::FxHashMap;

const SMALL_ELEMS: usize = 12;

/// A hybrid large/small-mode sparse mapping from integer indices to
/// elements.
///
/// The trailing `(u32, u64)` elements in each variant is a one-item
/// cache to allow fast access when streaming through.
#[derive(Clone, Debug)]
enum AdaptiveMap {
Small {
Expand Down Expand Up @@ -182,7 +178,6 @@ impl<'a> core::iter::Iterator for AdaptiveMapIter<'a> {
#[derive(Clone)]
pub struct IndexSet {
elems: AdaptiveMap,
cache: Cell<(u32, u64)>,
}

const BITS_PER_WORD: usize = 64;
Expand All @@ -191,36 +186,25 @@ impl IndexSet {
pub fn new() -> Self {
Self {
elems: AdaptiveMap::new(),
cache: Cell::new((INVALID, 0)),
}
}

#[inline(always)]
fn elem(&mut self, bit_index: usize) -> &mut u64 {
let word_index = (bit_index / BITS_PER_WORD) as u32;
if self.cache.get().0 == word_index {
self.cache.set((INVALID, 0));
}
self.elems.get_or_insert(word_index)
}

#[inline(always)]
fn maybe_elem_mut(&mut self, bit_index: usize) -> Option<&mut u64> {
let word_index = (bit_index / BITS_PER_WORD) as u32;
if self.cache.get().0 == word_index {
self.cache.set((INVALID, 0));
}
self.elems.get_mut(word_index)
}

#[inline(always)]
fn maybe_elem(&self, bit_index: usize) -> Option<u64> {
let word_index = (bit_index / BITS_PER_WORD) as u32;
if self.cache.get().0 == word_index {
Some(self.cache.get().1)
} else {
self.elems.get(word_index)
}
self.elems.get(word_index)
}

#[inline(always)]
Expand All @@ -235,7 +219,6 @@ impl IndexSet {

pub fn assign(&mut self, other: &Self) {
self.elems = other.elems.clone();
self.cache = other.cache.clone();
}

#[inline(always)]
Expand Down
Loading