From: mdw <mdw>
Date: Sun, 25 Jun 2000 12:59:02 +0000 (+0000)
Subject: (mpx_udiv): Fix bug in quotient digit estimation.
X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/commitdiff_plain/ce76ff166af224efbeadc7beaa6fdfd4b222c63b

(mpx_udiv): Fix bug in quotient digit estimation.
---

diff --git a/mpx.c b/mpx.c
index 36b424c..7f0b25a 100644
--- a/mpx.c
+++ b/mpx.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: mpx.c,v 1.7 1999/12/22 15:49:07 mdw Exp $
+ * $Id: mpx.c,v 1.8 2000/06/25 12:59:02 mdw Exp $
  *
  * Low-level multiprecision arithmetic
  *
@@ -30,6 +30,9 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: mpx.c,v $
+ * Revision 1.8  2000/06/25 12:59:02  mdw
+ * (mpx_udiv): Fix bug in quotient digit estimation.
+ *
  * Revision 1.7  1999/12/22 15:49:07  mdw
  * New function for division by a small integer.
  *
@@ -824,20 +827,18 @@ void mpx_udiv(mpw *qv, mpw *qvl, mpw *rv, mpw *rvl,
 
       {
 	mpd yh = (mpd)d * q;
-	mpd yl = (mpd)dd * q;
+	mpd yy = (mpd)dd * q;
+	mpw yl;
 
-	if (yl > MPW_MAX) {
-	  yh += yl >> MPW_BITS;
-	  yl &= MPW_MAX;
-	}
+	if (yy > MPW_MAX)
+	  yh += yy >> MPW_BITS;
+	yl = MPW(yy);
 
 	while (yh > rh || (yh == rh && yl > rrr)) {
 	  q--;
 	  yh -= d;
-	  if (yl < dd) {
-	    yh++;
-	    yl += MPW_MAX;
-	  }
+	  if (yl < dd)
+	    yh--;
 	  yl -= dd;
 	}
       }