Optimize rb_big2str0 and big2str_karatsuba

Ruby Development
1

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— bignum.c.org
+++ bignum.c
@@ -893,21 +893,6 @@
long lh, ll, m1;
VALUE b, q, r;

  • if (FIXNUM_P(x)) {
  •   VALUE str = rb_fix2str(x, base);

  •   char* str_ptr = RSTRING_PTR(str);

  •   long str_len = RSTRING_LEN(str);

  •   if (trim) {

  •       if (FIX2INT(x) == 0) return 0;

  •       MEMCPY(ptr, str_ptr, char, str_len);

  •       return str_len;

  •   }

  •   else {

  •       memset(ptr, '0', len - str_len);

  •       MEMCPY(ptr + len - str_len, str_ptr, char, str_len);

  •       return len;

  •   }
  • }
    if (BIGZEROP(x)) {
    if (trim) return 0;
    else {
    @@ -924,8 +909,10 @@
    bigdivmod(x, b, &q, &r);
    lh = big2str_karatsuba(q, base, ptr, (len - m1)/2,
    len - m1, hbase, trim);

  • rb_big_resize(q, 0);
    ll = big2str_karatsuba(r, base, ptr + lh, m1/2,
    m1, hbase, !lh && trim);

  • rb_big_resize(r, 0);

    return lh + ll;
    }
    @@ -968,6 +955,7 @@
    len = off + big2str_karatsuba(xx, base, ptr + off, n1,
    n2, hbase, trim);
    }

  • rb_big_resize(xx, 0);

    ptr[len] = ‘\0’;
    rb_str_resize(ss, len);

2

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In message “Re: [ruby-dev:36217] optimize rb_big2str0 and
big2str_karatsuba”
on Mon, 8 Sep 2008 22:17:46 +0900, TOYOFUKU Chikanobu
[email protected] writes:

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3

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