Merge branch 'master' of github.com:ethcore/parity into move_hash
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4bcc269565
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28
src/hash.rs
28
src/hash.rs
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@ -479,27 +479,37 @@ known_heap_size!(0, H32, H64, H128, Address, H256, H264, H512, H520, H1024, H204
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// Specialized HashMap and HashSet
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/// Hasher that just takes 8 bytes of the provided value.
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pub struct PlainHasher(u64);
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/// May only be used for keys which are 32 bytes.
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pub struct PlainHasher {
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prefix: [u8; 8],
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_marker: [u64; 0], // for alignment
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}
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impl Default for PlainHasher {
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#[inline]
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fn default() -> PlainHasher {
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PlainHasher(0)
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PlainHasher {
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prefix: [0; 8],
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_marker: [0; 0],
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}
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}
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}
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impl Hasher for PlainHasher {
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#[inline]
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fn finish(&self) -> u64 {
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self.0
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unsafe { ::std::mem::transmute(self.prefix) }
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}
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#[inline]
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fn write(&mut self, bytes: &[u8]) {
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debug_assert!(bytes.len() == 32);
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let mut prefix = [0u8; 8];
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prefix.clone_from_slice(&bytes[0..8]);
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self.0 = unsafe { ::std::mem::transmute(prefix) };
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for quarter in bytes.chunks(8) {
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for (x, y) in self.prefix.iter_mut().zip(quarter) {
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*x ^= *y
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}
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}
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}
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}
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@ -514,6 +524,12 @@ mod tests {
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use uint::*;
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use std::str::FromStr;
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#[test]
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fn hasher_alignment() {
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use std::mem::align_of;
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assert_eq!(align_of::<u64>(), align_of::<PlainHasher>());
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}
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#[test]
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#[cfg_attr(feature="dev", allow(eq_op))]
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fn hash() {
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