diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | bignum.c | 13 |
2 files changed, 15 insertions, 4 deletions
@@ -1,3 +1,9 @@ +Thu Jun 27 00:23:57 2013 Tanaka Akira <akr@fsij.org> + + * bignum.c (rb_big_pow): Retry if y is a Bignum and it is + representable as a Fixnum. + Use rb_absint_numwords. + Wed Jun 26 23:53:00 2013 Charlie Somerville <charliesome@ruby-lang.org> * ext/bigdecimal/bigdecimal.c (BigDecimal_save_rounding_mode): fix typo. @@ -4578,6 +4578,7 @@ rb_big_pow(VALUE x, VALUE y) double d; SIGNED_VALUE yy; + again: if (y == INT2FIX(0)) return INT2FIX(1); switch (TYPE(y)) { case T_FLOAT: @@ -4587,6 +4588,9 @@ rb_big_pow(VALUE x, VALUE y) break; case T_BIGNUM: + y = bignorm(y); + if (FIXNUM_P(y)) + goto again; rb_warn("in a**b, b may be too big"); d = rb_big2dbl(y); break; @@ -4599,11 +4603,12 @@ rb_big_pow(VALUE x, VALUE y) else { VALUE z = 0; SIGNED_VALUE mask; - const long xlen = RBIGNUM_LEN(x); - const long xbits = BITSPERDIG*xlen - nlz(RBIGNUM_DIGITS(x)[xlen-1]); - const long BIGLEN_LIMIT = 32*1024*1024; + const size_t xbits = rb_absint_numwords(x, 1, NULL); + const size_t BIGLEN_LIMIT = 32*1024*1024; - if ((xbits > BIGLEN_LIMIT) || (xbits * yy > BIGLEN_LIMIT)) { + if (xbits == (size_t)-1 || + (xbits > BIGLEN_LIMIT) || + (xbits * yy > BIGLEN_LIMIT)) { rb_warn("in a**b, b may be too big"); d = (double)yy; break; |