Release 2.1.4.

[u/mdw/catacomb] / gf-gcd.c

diff --git a/gf-gcd.c b/gf-gcd.c
index 048d29d..03cee47 100644 (file)
--- a/gf-gcd.c
+++ b/gf-gcd.c
@@ -7,7 +7,7 @@
  * (c) 2004 Straylight/Edgeware
  */
 
-/*----- Licensing notice --------------------------------------------------* 
+/*----- Licensing notice --------------------------------------------------*
  *
  * This file is part of Catacomb.
  *
@@ -15,12 +15,12 @@
  * it under the terms of the GNU Library General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License, or (at your option) any later version.
- * 
+ *
  * Catacomb is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU Library General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Library General Public
  * License along with Catacomb; if not, write to the Free
  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
@@ -51,7 +51,7 @@ void gf_gcd(mp **gcd, mp **xx, mp **yy, mp *a, mp *b)
   mp *x = MP_ONE, *X = MP_ZERO;
   mp *y = MP_ZERO, *Y = MP_ONE;
   mp *u, *v;
-  mp *q = MP_NEW;
+  mp *q = MP_NEW, *t, *spare = MP_NEW;
   unsigned f = 0;
 
 #define f_swap 1u
@@ -69,7 +69,7 @@ void gf_gcd(mp **gcd, mp **xx, mp **yy, mp *a, mp *b)
    */
 
   if (MPX_UCMP(a->v, a->vl, <, b->v, b->vl)) {
-    { mp *t = a; a = b; b = t; }
+    t = a; a = b; b = t;
     f |= f_swap;
   }
 
@@ -112,20 +112,19 @@ void gf_gcd(mp **gcd, mp **xx, mp **yy, mp *a, mp *b)
   v = MP_COPY(b);
 
   while (!MP_ZEROP(v)) {
-    mp *t;
     gf_div(&q, &u, u, v);
     if (f & f_ext) {
-      t = gf_mul(MP_NEW, X, q);
+      t = gf_mul(spare, X, q);
       t = gf_add(t, t, x);
-      MP_DROP(x); x = X; X = t;
-      t = gf_mul(MP_NEW, Y, q);
+      spare = x; x = X; X = t;
+      t = gf_mul(spare, Y, q);
       t = gf_add(t, t, y);
-      MP_DROP(y); y = Y; Y = t;
+      spare = y; y = Y; Y = t;
     }
     t = u; u = v; v = t;
   }
 
-  MP_DROP(q);
+  MP_DROP(q); if (spare) MP_DROP(spare);
   if (!gcd)
     MP_DROP(u);
   else {
@@ -141,7 +140,7 @@ void gf_gcd(mp **gcd, mp **xx, mp **yy, mp *a, mp *b)
     /* --- If @a@ and @b@ got swapped, swap the coefficients back --- */
 
     if (f & f_swap) {
-      mp *t = x; x = y; y = t;
+      t = x; x = y; y = t;
       t = a; a = b; b = t;
     }
 
@@ -205,8 +204,8 @@ static int gcd(dstr *v)
   gf_gcd(&gg, &xx, &yy, a, b);
   if (!MP_EQ(x, xx)) {
     fputs("\n*** gf_gcd(x) failed", stderr);
-    fputs("\na      = ", stderr); mp_writefile(a, stderr, 16);
-    fputs("\nb      = ", stderr); mp_writefile(b, stderr, 16);
+    fputs("\na     = ", stderr); mp_writefile(a, stderr, 16);
+    fputs("\nb     = ", stderr); mp_writefile(b, stderr, 16);
     fputs("\nexpect = ", stderr); mp_writefile(x, stderr, 16);
     fputs("\nresult = ", stderr); mp_writefile(xx, stderr, 16);
     fputc('\n', stderr);
@@ -214,8 +213,8 @@ static int gcd(dstr *v)
   }
   if (!MP_EQ(y, yy)) {
     fputs("\n*** gf_gcd(y) failed", stderr);
-    fputs("\na      = ", stderr); mp_writefile(a, stderr, 16);
-    fputs("\nb      = ", stderr); mp_writefile(b, stderr, 16);
+    fputs("\na     = ", stderr); mp_writefile(a, stderr, 16);
+    fputs("\nb     = ", stderr); mp_writefile(b, stderr, 16);
     fputs("\nexpect = ", stderr); mp_writefile(y, stderr, 16);
     fputs("\nresult = ", stderr); mp_writefile(yy, stderr, 16);
     fputc('\n', stderr);
@@ -234,8 +233,8 @@ static int gcd(dstr *v)
 
   if (!MP_EQ(g, gg)) {
     fputs("\n*** gf_gcd(gcd) failed", stderr);
-    fputs("\na      = ", stderr); mp_writefile(a, stderr, 16);
-    fputs("\nb      = ", stderr); mp_writefile(b, stderr, 16);
+    fputs("\na     = ", stderr); mp_writefile(a, stderr, 16);
+    fputs("\nb     = ", stderr); mp_writefile(b, stderr, 16);
     fputs("\nexpect = ", stderr); mp_writefile(g, stderr, 16);
     fputs("\nresult = ", stderr); mp_writefile(gg, stderr, 16);
     fputc('\n', stderr);