Int - Bit ops
#697
Int - Bit ops
#697
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| pub const fn expect(self, msg: &str) -> Int<LIMBS> { | ||
| assert!(self.is_some.is_true_vartime(), "{}", msg); | ||
| self.value | ||
| } |
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I copy-pasted this from ConstCtOption<Uint>.
In doing so, I did notice that, although it uses is_true_vartime, ConstCtOption<Uint>::expect was not annotated as being vartime. Moreover, it is used for Uint::shr and Uint::shl, among others, which are not vartime either. Is this OK because unwraps are vartime anyway, or do we need to do something about this @tarcieri ?
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They're not really "vartime" in that if the condition is violated, it will crash the entire program, as opposed to completing successfully in a variable number of CPU cycles
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@tarcieri this is the next PR ready for review. I am looking forward to your input! |
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@tarcieri ping 😄 |
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@lleoha IMHO, I see no added value in supporting logical (=unsigned) right shift on a signed integer: it could be confusing for users, and the difference is quite subtle. Moreover, when logically shifting-right a negative value, you get some bizarre behaviour. To illustrate with an Moreover, if for some reason you really need the logical shift right, the solution |
I'm sold :). |
Bit operations on
Int, in preparation for implementingIntegertrait.