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-rw-r--r--tcl8.6/libtommath/bn_mp_sub_d.c89
1 files changed, 0 insertions, 89 deletions
diff --git a/tcl8.6/libtommath/bn_mp_sub_d.c b/tcl8.6/libtommath/bn_mp_sub_d.c
deleted file mode 100644
index b1e4e3f..0000000
--- a/tcl8.6/libtommath/bn_mp_sub_d.c
+++ /dev/null
@@ -1,89 +0,0 @@
-#include <tommath.h>
-#ifdef BN_MP_SUB_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.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- *
- * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
- */
-
-/* single digit subtraction */
-int
-mp_sub_d (mp_int * a, mp_digit b, mp_int * c)
-{
- mp_digit *tmpa, *tmpc, mu;
- int res, ix, oldused;
-
- /* grow c as required */
- if (c->alloc < a->used + 1) {
- if ((res = mp_grow(c, a->used + 1)) != MP_OKAY) {
- return res;
- }
- }
-
- /* if a is negative just do an unsigned
- * addition [with fudged signs]
- */
- if (a->sign == MP_NEG) {
- a->sign = MP_ZPOS;
- res = mp_add_d(a, b, c);
- a->sign = c->sign = MP_NEG;
-
- /* clamp */
- mp_clamp(c);
-
- return res;
- }
-
- /* setup regs */
- oldused = c->used;
- tmpa = a->dp;
- tmpc = c->dp;
-
- /* if a <= b simply fix the single digit */
- if ((a->used == 1 && a->dp[0] <= b) || a->used == 0) {
- if (a->used == 1) {
- *tmpc++ = b - *tmpa;
- } else {
- *tmpc++ = b;
- }
- ix = 1;
-
- /* negative/1digit */
- c->sign = MP_NEG;
- c->used = 1;
- } else {
- /* positive/size */
- c->sign = MP_ZPOS;
- c->used = a->used;
-
- /* subtract first digit */
- *tmpc = *tmpa++ - b;
- mu = *tmpc >> (sizeof(mp_digit) * CHAR_BIT - 1);
- *tmpc++ &= MP_MASK;
-
- /* handle rest of the digits */
- for (ix = 1; ix < a->used; ix++) {
- *tmpc = *tmpa++ - mu;
- mu = *tmpc >> (sizeof(mp_digit) * CHAR_BIT - 1);
- *tmpc++ &= MP_MASK;
- }
- }
-
- /* zero excess digits */
- while (ix++ < oldused) {
- *tmpc++ = 0;
- }
- mp_clamp(c);
- return MP_OKAY;
-}
-
-#endif