From: TOYOFUKU Chikanobu <nobu_toyofuku@...>
Date: 2008-09-02T18:10:38+09:00
Subject: [ruby-dev:36100] optimize bigdivrem Part 3

  豊福です。

  bigdivrem の計算過程で使うオブジェクトの節約です。
生で ALLOC_N と free を使うのはよくない？

--- bignum.c.org
+++ bignum.c
@@ -1678,8 +1678,8 @@
     struct big_div_struct bds;
     long nx = RBIGNUM_LEN(x), ny = RBIGNUM_LEN(y), nz;
     long i, j;
-    volatile VALUE yy, z;
-    BDIGIT *xds, *yds, *zds, *tds;
+    volatile VALUE z;
+    BDIGIT *xds, *yds, *zds, *tds = 0;
     BDIGIT_DBL t2;
     BDIGIT dd, q;

@@ -1729,8 +1729,7 @@
        dd++;
     }
     if (dd) {
-       yy = rb_big_clone(y);
-       tds = BDIGITS(yy);
+       tds = ALLOC_N(BDIGIT, ny);
        j = 0;
        t2 = 0;
        while (j<ny) {
@@ -1766,6 +1765,8 @@
        bigdivrem1(&bds);
     }

+    if (tds) free(tds);
+
     if (divp) {                        /* move quotient down in z */
        *divp = modp ? rb_big_clone(z): z;
        zds = BDIGITS(*divp);

---