nac3core: unification table optimization

avoid cloning values that we no longer need.
This commit is contained in:
pca006132 2021-08-27 13:05:06 +08:00
parent 8c1c7fcfc3
commit 72aebed559
1 changed files with 11 additions and 6 deletions

View File

@ -1,5 +1,7 @@
use std::rc::Rc; use std::rc::Rc;
use itertools::izip;
#[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)] #[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
pub struct UnificationKey(usize); pub struct UnificationKey(usize);
@ -7,7 +9,7 @@ pub struct UnificationKey(usize);
pub struct UnificationTable<V> { pub struct UnificationTable<V> {
parents: Vec<usize>, parents: Vec<usize>,
ranks: Vec<u32>, ranks: Vec<u32>,
values: Vec<V>, values: Vec<Option<V>>,
} }
impl<V> UnificationTable<V> { impl<V> UnificationTable<V> {
@ -19,7 +21,7 @@ impl<V> UnificationTable<V> {
let index = self.parents.len(); let index = self.parents.len();
self.parents.push(index); self.parents.push(index);
self.ranks.push(0); self.ranks.push(0);
self.values.push(v); self.values.push(Some(v));
UnificationKey(index) UnificationKey(index)
} }
@ -40,12 +42,12 @@ impl<V> UnificationTable<V> {
pub fn probe_value(&mut self, a: UnificationKey) -> &V { pub fn probe_value(&mut self, a: UnificationKey) -> &V {
let index = self.find(a); let index = self.find(a);
&self.values[index] self.values[index].as_ref().unwrap()
} }
pub fn set_value(&mut self, a: UnificationKey, v: V) { pub fn set_value(&mut self, a: UnificationKey, v: V) {
let index = self.find(a); let index = self.find(a);
self.values[index] = v; self.values[index] = Some(v);
} }
pub fn unioned(&mut self, a: UnificationKey, b: UnificationKey) -> bool { pub fn unioned(&mut self, a: UnificationKey, b: UnificationKey) -> bool {
@ -77,12 +79,15 @@ where
V: Clone, V: Clone,
{ {
pub fn get_send(&self) -> UnificationTable<V> { pub fn get_send(&self) -> UnificationTable<V> {
let values = self.values.iter().map(|v| v.as_ref().clone()).collect(); let values = izip!(self.values.iter(), self.parents.iter())
.enumerate()
.map(|(i, (v, p))| if *p == i { v.as_ref().map(|v| v.as_ref().clone()) } else { None })
.collect();
UnificationTable { parents: self.parents.clone(), ranks: self.ranks.clone(), values } UnificationTable { parents: self.parents.clone(), ranks: self.ranks.clone(), values }
} }
pub fn from_send(table: &UnificationTable<V>) -> UnificationTable<Rc<V>> { pub fn from_send(table: &UnificationTable<V>) -> UnificationTable<Rc<V>> {
let values = table.values.iter().cloned().map(Rc::new).collect(); let values = table.values.iter().cloned().map(|v| v.map(Rc::new)).collect();
UnificationTable { parents: table.parents.clone(), ranks: table.ranks.clone(), values } UnificationTable { parents: table.parents.clone(), ranks: table.ranks.clone(), values }
} }
} }