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Reduce the need for float arithmetics
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Signed-off-by: Heinz N. Gies <[email protected]>
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@Licenser
Licenser committed Aug 9, 2024
1 parent 8875e1a commit af67547
Showing 1 changed file with 9 additions and 95 deletions.
104 changes: 9 additions & 95 deletions src/htb.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -42,20 +42,19 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {
}
}
#[inline]
#[allow(clippy::cast_possible_truncation)]
#[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
/// Inserts a value into the counter
pub fn insert<V: std::hash::Hash>(&mut self, v: &V) {
let threshold: u32 = const { (Self::ALPHA * BITS::M as f64) as u32 };
let mut x = HASH::default();
v.hash(&mut x);
let x = x.finish();
// use most significant bits for k the rest for x
let k: u32 = (x >> BITS::K_SHIFT) as u32;
let x: u64 = x & BITS::X_MASK;
let mut count_changed = false;

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -68,75 +67,18 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {
self.sketch.set(k, 3);
}

if count_changed && f64::from(self.count) >= Self::ALPHA * f64::from(BITS::M) {
if self.count >= threshold {
self.count = self.sketch.decrement();
self.t += 4;
}
}

#[inline]
#[allow(clippy::cast_possible_truncation)]
#[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
/// Inserts 2 elements into the counter for micro batching purposes, note this will delay
/// the count update to the end
pub fn insert2<V: std::hash::Hash>(&mut self, v1: &V, v2: &V) {
let mut count_changed = false;

let mut x = HASH::default();
v1.hash(&mut x);
let x = x.finish();
// use most significant bits for k the rest for x
let k: u32 = (x >> BITS::K_SHIFT) as u32;
let x: u64 = x & BITS::X_MASK;

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
if x.trailing_ones() >= self.t + 4 && self.sketch.val(k) < 2 {
self.sketch.set(k, 2);
}

// 2^8
if x.trailing_ones() >= self.t + 8 && self.sketch.val(k) < 3 {
self.sketch.set(k, 3);
}

let mut x = HASH::default();
v2.hash(&mut x);
let x = x.finish();
// use most significant bits for k the rest for x
let k: u32 = (x >> BITS::K_SHIFT) as u32;
let x: u64 = x & BITS::X_MASK;

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
if x.trailing_ones() >= self.t + 4 && self.sketch.val(k) < 2 {
self.sketch.set(k, 2);
}

// 2^8
if x.trailing_ones() >= self.t + 8 && self.sketch.val(k) < 3 {
self.sketch.set(k, 3);
}

if count_changed && f64::from(self.count) >= Self::ALPHA * f64::from(BITS::M) {
self.count = self.sketch.decrement();
self.t += 4;
}
}

#[inline]
#[allow(clippy::cast_possible_truncation)]
/// Inserts 3 elements into the counter for micro batching purposes, note this will delay
/// the count update to the end
pub fn insert3<V: std::hash::Hash>(&mut self, v1: &V, v2: &V, v3: &V) {
let mut count_changed = false;
let threshold: u32 = const { (Self::ALPHA * BITS::M as f64) as u32 };

let mut x = HASH::default();
v1.hash(&mut x);
Expand All @@ -147,7 +89,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -169,7 +110,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -182,40 +122,18 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {
self.sketch.set(k, 3);
}

let mut x = HASH::default();
v3.hash(&mut x);
let x = x.finish();
// use most significant bits for k the rest for x
let k: u32 = (x >> BITS::K_SHIFT) as u32;
let x: u64 = x & BITS::X_MASK;

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
if x.trailing_ones() >= self.t + 4 && self.sketch.val(k) < 2 {
self.sketch.set(k, 2);
}

// 2^8
if x.trailing_ones() >= self.t + 8 && self.sketch.val(k) < 3 {
self.sketch.set(k, 3);
}

if count_changed && f64::from(self.count) >= Self::ALPHA * f64::from(BITS::M) {
if self.count >= threshold {
self.count = self.sketch.decrement();
self.t += 4;
}
}

#[inline]
#[allow(clippy::cast_possible_truncation)]
#[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
/// Inserts 4 elements into the counter for micro batching purposes, note this will delay
/// the count update to the end
pub fn insert4<V: std::hash::Hash>(&mut self, v1: &V, v2: &V, v3: &V, v4: &V) {
let mut count_changed = false;
let threshold: u32 = const { (Self::ALPHA * BITS::M as f64) as u32 };

let mut x = HASH::default();
v1.hash(&mut x);
Expand All @@ -226,7 +144,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -248,7 +165,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -270,7 +186,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -292,7 +207,6 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {

if x.trailing_ones() >= self.t && self.sketch.val(k) < 1 {
self.count += 1;
count_changed = true;
self.sketch.set(k, 1);
}
// 2^4
Expand All @@ -305,7 +219,7 @@ impl<HASH: Hasher + Default, BITS: Sketch> HyperTwoBits<BITS, HASH> {
self.sketch.set(k, 3);
}

if count_changed && f64::from(self.count) >= Self::ALPHA * f64::from(BITS::M) {
if self.count >= threshold {
self.count = self.sketch.decrement();
self.t += 4;
}
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