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authorjan.nijtmans <nijtmans@users.sourceforge.net>2019-06-13 19:07:13 (GMT)
committerjan.nijtmans <nijtmans@users.sourceforge.net>2019-06-13 19:07:13 (GMT)
commit505f963287b050bd46871d4659cebc65986ca5ac (patch)
tree853ad3262ab07f7c5755e76b8154f36f24608014 /libtommath/bn_mp_add_d.c
parent689987ea924a8fded1801777c1a14ab1205fa826 (diff)
downloadtcl-505f963287b050bd46871d4659cebc65986ca5ac.zip
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Update to latest libtommath's "develop" branch. On the way to 1.2.0
Diffstat (limited to 'libtommath/bn_mp_add_d.c')
-rw-r--r--libtommath/bn_mp_add_d.c50
1 files changed, 15 insertions, 35 deletions
diff --git a/libtommath/bn_mp_add_d.c b/libtommath/bn_mp_add_d.c
index ecdb791..f301575 100644
--- a/libtommath/bn_mp_add_d.c
+++ b/libtommath/bn_mp_add_d.c
@@ -1,27 +1,19 @@
#include "tommath_private.h"
#ifdef BN_MP_ADD_D_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 */
/* single digit addition */
-int mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
+mp_err mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
{
- int res, ix, oldused;
- mp_digit *tmpa, *tmpc, mu;
+ mp_err err;
+ int ix, oldused;
+ mp_digit *tmpa, *tmpc;
/* grow c as required */
if (c->alloc < (a->used + 1)) {
- if ((res = mp_grow(c, a->used + 1)) != MP_OKAY) {
- return res;
+ if ((err = mp_grow(c, a->used + 1)) != MP_OKAY) {
+ return err;
}
}
@@ -32,7 +24,7 @@ int mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
a_.sign = MP_ZPOS;
/* c = |a| - b */
- res = mp_sub_d(&a_, b, c);
+ err = mp_sub_d(&a_, b, c);
/* fix sign */
c->sign = MP_NEG;
@@ -40,7 +32,7 @@ int mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
/* clamp */
mp_clamp(c);
- return res;
+ return err;
}
/* old number of used digits in c */
@@ -54,17 +46,11 @@ int mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
/* if a is positive */
if (a->sign == MP_ZPOS) {
- /* add digit, after this we're propagating
- * the carry.
- */
- *tmpc = *tmpa++ + b;
- mu = *tmpc >> DIGIT_BIT;
- *tmpc++ &= MP_MASK;
-
- /* now handle rest of the digits */
- for (ix = 1; ix < a->used; ix++) {
+ /* add digits, mu is carry */
+ mp_digit mu = b;
+ for (ix = 0; ix < a->used; ix++) {
*tmpc = *tmpa++ + mu;
- mu = *tmpc >> DIGIT_BIT;
+ mu = *tmpc >> MP_DIGIT_BIT;
*tmpc++ &= MP_MASK;
}
/* set final carry */
@@ -94,16 +80,10 @@ int mp_add_d(const mp_int *a, mp_digit b, mp_int *c)
c->sign = MP_ZPOS;
/* now zero to oldused */
- while (ix++ < oldused) {
- *tmpc++ = 0;
- }
+ MP_ZERO_DIGITS(tmpc, oldused - ix);
mp_clamp(c);
return MP_OKAY;
}
#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */