It has no effect on correctness, but interferes with compating internal state
of different implementations.
function old new delta
sp_256_proj_point_dbl_10 443 451 +8
static.sp_256_mont_sub_10 46 49 +3
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(add/remove: 0/0 grow/shrink: 2/0 up/down: 11/0) Total: 11 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>