mpi division truncation mode
D. Hugh Redelmeier
Tue, 26 Oct 1999 12:58:58 -0400 (EDT)
As I've mentioned, I'm trying to wean dsa.c, elgamal.c, and primegen.c
My current theory is that every mpi number used in gcrypt is non-negative.
Is this correct? If so, could the mpi code be simplified?
(Perhaps it is even the case that all mpi numbers in gcrypt are
actually representatives members of a finite ring of integers mod
I've noticed that every mpi divide I've come across uses "f" (floor)
rounding (towards -infinity). Except for one in primegen.c:is_prime -- it
uses mpi_tdiv_q_2exp. "t" (truncate) rounds towards 0. If the numbers
concerned are never negative, then this is a distinction without a
This is just idle curiosity -- how I learn things.
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