28 lines
435 B
Go
28 lines
435 B
Go
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package alias
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// For details: https://en.wikipedia.org/wiki/Linear-feedback_shift_register
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type LSFR struct {
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data uint64
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poly uint64
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}
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func newLSFR(poly uint64, seed uint64) *LSFR {
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return &LSFR{data: seed, poly: poly}
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}
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func (f *LSFR) next() uint64 {
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var bit uint64
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var i uint64
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for i = 0; i < 64; i++ {
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if f.poly&(1<<i) != 0 {
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bit ^= (f.data >> i)
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}
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}
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bit &= 0x01
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f.data = (f.data << 1) | bit
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return f.data
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}
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