31 lines
617 B
Rust
31 lines
617 B
Rust
#[derive(Debug)]
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pub struct HistoLog2 {
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histo: [u64; 16],
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sub: usize,
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}
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impl HistoLog2 {
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pub fn new(sub: usize) -> Self {
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Self { histo: [0; 16], sub }
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}
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#[inline]
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pub fn ingest(&mut self, mut v: u32) {
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let mut po = 0;
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while v != 0 && po < 15 {
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v = v >> 1;
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po += 1;
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}
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let po = if po >= self.histo.len() + self.sub {
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self.histo.len() - 1
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} else {
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if po > self.sub {
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po - self.sub
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} else {
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0
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}
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};
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self.histo[po] += 1;
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}
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}
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