modernize bigdiv()

1 files changed, 22 insertions, 16 deletions

diff --git a/big.c b/big.c
index b7c1186..d5341ac 100644
--- a/big.c
+++ b/big.c
@@ -356,24 +356,28 @@ word stimes(word x, word n)
   return r;
 }
 
+/* TODO: make bigdiv()/bigmod() behave like div()/ldiv()/lldiv() */
 word b_rem;			/* contains remainder from last call to longdiv or shortdiv */
 
-word bigdiv(x, y)		/* may assume y~=0 */
-word x, y;
+/* may assume y~=0 */
+word bigdiv(word x, word y)
 {
-  word s1, s2, q;
+  word s1 = big_is_negative(y);
+  word s2 = s1;
+
   /* make x,y positive and remember signs */
-  if (s1 = big_is_negative(y))
+  if (s1 = big_is_negative(y)) {
     y = make(INT, digit0(y), rest(y));
-  if (big_is_negative(x))
-    x = make(INT, digit0(x), rest(x)), s2 = !s1;
-  else
-    s2 = s1;
+  }
+
   /* effect: s1 set iff y negative, s2 set iff signs mixed */
-  if (rest(y))
-    q = longdiv(x, y);
-  else
-    q = shortdiv(x, digit(y));
+  if (big_is_negative(x)) {
+    x = make(INT, digit0(x), rest(x));
+    s2 = !s1;
+  }
+
+  word q = rest(y) ? longdiv(x, y) : shortdiv(x, digit(y));
+
   if (s2) {
     if (!bigzero(b_rem)) {
       x = q;
@@ -382,14 +386,16 @@ word x, y;
 	if (!rest(x)) {
 	  rest(x) = make(INT, 1, 0);
 	  break;
-	} else
-	  x = rest(x);
+	}
+        x = rest(x);
       }
     }
-    if (!bigzero(q))
+    if (!bigzero(q)) {
       digit(q) = SIGNBIT | digit(q);
+    }
   }
-  return (q);
+
+  return q;
 }
 
 word bigmod(x, y)		/* may assume y~=0 */