Ruby Forum Ruby-dev > optimize bigdivrem1

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--- bignum.c.org
+++ bignum.c
@@ -1633,19 +1633,20 @@
 {
     struct big_div_struct *bds = (struct big_div_struct*)ptr;
     long nx = bds->nx, ny = bds->ny;
-    long i, j;
+    long i, j, nyzero;
     BDIGIT *yds = bds->yds, *zds = bds->zds;
     BDIGIT_DBL t2;
     BDIGIT_DBL_SIGNED num;
     BDIGIT q;

     j = nx==ny?nx+1:nx;
+    for (nyzero = 0; !yds[nyzero]; nyzero++);
     do {
        if (bds->stop) return Qnil;
        if (zds[j] ==  yds[ny-1]) q = BIGRAD-1;
        else q = (BDIGIT)((BIGUP(zds[j]) + zds[j-1])/yds[ny-1]);
        if (q) {
-           i = 0; num = 0; t2 = 0;
+           i = nyzero; num = 0; t2 = 0;
            do {                        /* multiply and subtract */
                BDIGIT_DBL ee;
                t2 += (BDIGIT_DBL)yds[i] * q;

---

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In message "Re: [ruby-dev:36169] optimize bigdivrem1"
    on Fri, 5 Sep 2008 21:13:54 +0900, TOYOFUKU Chikanobu 
<nobu_toyofuku@nifty.com> writes:

|  $B8e$m$N(B zero $B$,O"$J$C$F$$$kItJ,$N=hM}$r>J$-$^$9!#(B
|Bignum#to_s $B$N4p?t$,#2$N$Y$->h$N$H$-$KHs>o$K8z2L$,$"$j$^$9!#(B
|$B!J$b$C$H$b(B rb_big2str0 $B$G4p?t$,#2$N$Y$->h$N$H$-$rJL=hM}$K$9$l$P(B
|$B$5$i$K7cB.$K$J$k$O$:$G$9$,!K(B
|$B4p?t$,#1#0$N$H$-$b$=$3$=$38z2L$"$j$^$9!#(B

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