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Re: streql - Constant-time string comparison

On 30/10/14 01:34, Leslie S Satenstein wrote:
> Hi Riley
> Suppose the strings are 10k bytes each (10240), but they differ at byte zero, 
> where is the break instruction to stop the compare?

Why would there need to be a break instruction? That would mean that the
time taken to compare strings of equal length would change depending on
the length of the string, unless I'm mistaken.

> The code needs an addition to the for loop as shown below. 
> In place of xor, the return of a comparison when non zero is encountered would allow one to know if string x < string y or the contrary.

Sorry, but I don't understand what you mean. Why is it important to be
able to know whether string x > string y or vice versa?

>  Regards 
>  Leslie
>  Mr. Leslie Satenstein
> Montréal Québec, Canada

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