pub fn prepare()Expand description
Build every precomputed table now, rather than on first use.
Under std, the generator tables for P-256, P-384 and P-521 and the
Ed25519 basepoint tables are built the first time an operation needs them:
about one scalar multiplication per curve, a few hundred microseconds in
all on a host. They live in statics, so building them allocates nothing
whenever it happens. What this changes is when the time is spent: a
caller that wants its first handshake to cost what every later one does can
pay it at start-up instead.
Safe to call more than once and from several threads: the work is done
once, and a second caller waits for the first. Under no_std there are no
tables, and this does nothing.