diff options
Diffstat (limited to 'numeric.c')
| -rw-r--r-- | numeric.c | 26 |
1 files changed, 21 insertions, 5 deletions
@@ -109,6 +109,7 @@ static VALUE fix_lshift(long, unsigned long); static VALUE fix_rshift(long, unsigned long); static VALUE int_pow(long x, unsigned long y); static VALUE int_cmp(VALUE x, VALUE y); +static int int_round_zero_p(VALUE num, int ndigits); static VALUE flo_truncate(VALUE num); static int float_invariant_round(double number, int ndigits, VALUE *num); @@ -1766,6 +1767,24 @@ flo_ceil(VALUE num) return dbl2ival(f); } +static int +int_round_zero_p(VALUE num, int ndigits) +{ + long bytes; + /* If 10**N / 2 > num, then return 0 */ + /* We have log_256(10) > 0.415241 and log_256(1/2) = -0.125, so */ + if (FIXNUM_P(num)) { + bytes = sizeof(long); + } + else if (RB_TYPE_P(num, T_BIGNUM)) { + bytes = rb_big_size(num); + } + else { + bytes = NUM2LONG(rb_funcall(num, idSize, 0)); + } + return (-0.415241 * ndigits - 0.125 > bytes); +} + /* * Assumes num is an Integer, ndigits <= 0 */ @@ -1773,11 +1792,8 @@ VALUE rb_int_round(VALUE num, int ndigits) { VALUE n, f, h, r; - long bytes; - /* If 10**N / 2 > num, then return 0 */ - /* We have log_256(10) > 0.415241 and log_256(1/2) = -0.125, so */ - bytes = FIXNUM_P(num) ? sizeof(long) : rb_funcall(num, idSize, 0); - if (-0.415241 * ndigits - 0.125 > bytes ) { + + if (int_round_zero_p(num, ndigits)) { return INT2FIX(0); } |