improve mp_lshd

This fixes #61
2017-08-29 23:53:02 +02:00 · 2017-08-29 23:53:02 +02:00 · 356084ee31
commit 356084ee31
parent 1d03522625
1 changed files with 4 additions and 0 deletions
--- a/bn_mp_lshd.c
+++ b/bn_mp_lshd.c
@ -24,6 +24,10 @@ int mp_lshd(mp_int *a, int b)
   if (b <= 0) {
      return MP_OKAY;
   }
+   /* no need to shift 0 around */
+   if (mp_iszero(a) == MP_YES) {
+      return MP_OKAY;
+   }

   /* grow to fit the new digits */
   if (a->alloc < (a->used + b)) {