Messages in this thread | | | Date | Wed, 1 Apr 2015 09:53:25 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH] lfsr: a simple binary Galois linear feedback shift register |
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On Tue, Mar 31, 2015 at 01:28:09PM -0400, Waiman Long wrote: > +static __always_inline u32 lfsr_taps(int bits)
> +static inline u32 lfsr(u32 val, int bits) > +{ > + u32 bit = val & 1; > + > + /* > + * LFSR doesn't work with a start state of 0, so force it to a > + * non-zero value (bits) as the next state. > + */ > + if (val == 0) > + return bits;
Arguably this should be a debug/warn instead of a silent modification.
> + val >>= 1; > + if (bit) > + val ^= lfsr_taps(bits); > + return val; > +}
I was also thinking that if we modify the hash to be dynamically signed we cannot use the compile time tap selection and need to change the interface slightly.
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