1 files changed, 25 insertions, 41 deletions

diff --git a/libtommath/bn_mp_div_2.c b/libtommath/bn_mp_div_2.c
index a84e9f0..f56ea81 100644
--- a/libtommath/bn_mp_div_2.c
+++ b/libtommath/bn_mp_div_2.c
@@ -1,65 +1,49 @@
 #include "tommath_private.h"
 #ifdef BN_MP_DIV_2_C
-/* LibTomMath, multiple-precision integer library -- Tom St Denis
- *
- * LibTomMath is a library that provides multiple-precision
- * integer arithmetic as well as number theoretic functionality.
- *
- * The library was designed directly after the MPI library by
- * Michael Fromberger but has been written from scratch with
- * additional optimizations in place.
- *
- * SPDX-License-Identifier: Unlicense
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
 
 /* b = a/2 */
-int mp_div_2(const mp_int *a, mp_int *b)
+mp_err mp_div_2(const mp_int *a, mp_int *b)
 {
-   int     x, res, oldused;
+   int     x, oldused;
+   mp_digit r, rr, *tmpa, *tmpb;
+   mp_err err;
 
    /* copy */
    if (b->alloc < a->used) {
-      if ((res = mp_grow(b, a->used)) != MP_OKAY) {
-         return res;
+      if ((err = mp_grow(b, a->used)) != MP_OKAY) {
+         return err;
       }
    }
 
    oldused = b->used;
    b->used = a->used;
-   {
-      mp_digit r, rr, *tmpa, *tmpb;
 
-      /* source alias */
-      tmpa = a->dp + b->used - 1;
+   /* source alias */
+   tmpa = a->dp + b->used - 1;
 
-      /* dest alias */
-      tmpb = b->dp + b->used - 1;
+   /* dest alias */
+   tmpb = b->dp + b->used - 1;
 
-      /* carry */
-      r = 0;
-      for (x = b->used - 1; x >= 0; x--) {
-         /* get the carry for the next iteration */
-         rr = *tmpa & 1u;
+   /* carry */
+   r = 0;
+   for (x = b->used - 1; x >= 0; x--) {
+      /* get the carry for the next iteration */
+      rr = *tmpa & 1u;
 
-         /* shift the current digit, add in carry and store */
-         *tmpb-- = (*tmpa-- >> 1) | (r << (DIGIT_BIT - 1));
+      /* shift the current digit, add in carry and store */
+      *tmpb-- = (*tmpa-- >> 1) | (r << (MP_DIGIT_BIT - 1));
 
-         /* forward carry to next iteration */
-         r = rr;
-      }
-
-      /* zero excess digits */
-      tmpb = b->dp + b->used;
-      for (x = b->used; x < oldused; x++) {
-         *tmpb++ = 0;
-      }
+      /* forward carry to next iteration */
+      r = rr;
    }
+
+   /* zero excess digits */
+   MP_ZERO_DIGITS(b->dp + b->used, oldused - b->used);
+
    b->sign = a->sign;
    mp_clamp(b);
    return MP_OKAY;
 }
 #endif
-
-/* ref:         HEAD -> master, tag: v1.1.0 */
-/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
-/* commit time: 2019-01-28 20:32:32 +0100 */