3.7.6, 3.7.7 Optimize multiexp implementations

This commit is contained in:
Luke Parker
2023-03-02 06:12:02 -05:00
parent e5329b42e6
commit 1d2ebdca62
2 changed files with 35 additions and 13 deletions

View File

@@ -15,8 +15,10 @@ where
let mut res = G::identity();
for n in (0 .. bits[0].len()).rev() {
for _ in 0 .. window {
res = res.double();
if n != (bits[0].len() - 1) {
for _ in 0 .. window {
res = res.double();
}
}
let mut buckets = vec![G::identity(); 2_usize.pow(window.into())];
@@ -49,18 +51,32 @@ where
}
}
let mut buckets = vec![G::identity(); 2_usize.pow(window.into())];
// Use None to represent identity since is_none is likely faster than is_identity
let mut buckets = vec![None; 2_usize.pow(window.into())];
for p in 0 .. bits.len() {
let nibble = usize::from(bits[p][n]);
if nibble != 0 {
buckets[nibble] += pairs[p].1;
if let Some(bucket) = buckets[nibble].as_mut() {
*bucket += pairs[p].1;
} else {
buckets[nibble] = Some(pairs[p].1);
}
}
}
let mut intermediate_sum = G::identity();
let mut intermediate_sum = None;
for b in (1 .. buckets.len()).rev() {
intermediate_sum += buckets[b];
res += intermediate_sum;
if let Some(bucket) = buckets[b].as_ref() {
if let Some(intermediate_sum) = intermediate_sum.as_mut() {
*intermediate_sum += bucket;
} else {
intermediate_sum = Some(*bucket);
}
}
if let Some(intermediate_sum) = intermediate_sum.as_ref() {
res += intermediate_sum;
}
}
}