63 lines
1.1 KiB
Go
63 lines
1.1 KiB
Go
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package ipbits
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import (
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"encoding/binary"
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"math/bits"
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)
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type uint128 struct{ hi, lo uint64 }
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func uint128From16(b [16]byte) uint128 {
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return uint128{
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hi: binary.BigEndian.Uint64(b[:8]),
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lo: binary.BigEndian.Uint64(b[8:]),
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}
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}
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func uint128From(x uint64) uint128 {
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return uint128{lo: x}
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}
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func (x uint128) add(y uint128) uint128 {
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lo, carry := bits.Add64(x.lo, y.lo, 0)
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hi, _ := bits.Add64(x.hi, y.hi, carry)
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return uint128{hi: hi, lo: lo}
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}
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func (x uint128) lsh(n uint) uint128 {
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if n > 64 {
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return uint128{hi: x.lo << (n - 64)}
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}
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return uint128{
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hi: x.hi<<n | x.lo>>(64-n),
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lo: x.lo << n,
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}
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}
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func (x uint128) rsh(n uint) uint128 {
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if n > 64 {
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return uint128{lo: x.hi >> (n - 64)}
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}
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return uint128{
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hi: x.hi >> n,
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lo: x.lo>>n | x.hi<<(64-n),
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}
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}
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func (x uint128) and(y uint128) uint128 {
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return uint128{hi: x.hi & y.hi, lo: x.lo & y.lo}
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}
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func (x uint128) not() uint128 {
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return uint128{hi: ^x.hi, lo: ^x.lo}
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}
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func (x uint128) fill16(a *[16]byte) {
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binary.BigEndian.PutUint64(a[:8], x.hi)
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binary.BigEndian.PutUint64(a[8:], x.lo)
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}
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func (x uint128) uint64() uint64 {
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return x.lo
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}
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