ruby/internal/bignum.h

#ifndef INTERNAL_BIGNUM_H /* -*- C -*- */
#define INTERNAL_BIGNUM_H
/**
 * @file
 * @brief      Internal header for Bignums.
 * @author     \@shyouhei
 * @copyright  This  file  is   a  part  of  the   programming  language  Ruby.
 *             Permission  is hereby  granted,  to  either redistribute  and/or
 *             modify this file, provided that  the conditions mentioned in the
 *             file COPYING are met.  Consult the file for details.
 */

#ifndef BDIGIT
# if SIZEOF_INT*2 <= SIZEOF_LONG_LONG
#  define BDIGIT unsigned int
#  define SIZEOF_BDIGIT SIZEOF_INT
#  define BDIGIT_DBL unsigned LONG_LONG
#  define BDIGIT_DBL_SIGNED LONG_LONG
#  define PRI_BDIGIT_PREFIX ""
#  define PRI_BDIGIT_DBL_PREFIX PRI_LL_PREFIX
# elif SIZEOF_INT*2 <= SIZEOF_LONG
#  define BDIGIT unsigned int
#  define SIZEOF_BDIGIT SIZEOF_INT
#  define BDIGIT_DBL unsigned long
#  define BDIGIT_DBL_SIGNED long
#  define PRI_BDIGIT_PREFIX ""
#  define PRI_BDIGIT_DBL_PREFIX "l"
# elif SIZEOF_SHORT*2 <= SIZEOF_LONG
#  define BDIGIT unsigned short
#  define SIZEOF_BDIGIT SIZEOF_SHORT
#  define BDIGIT_DBL unsigned long
#  define BDIGIT_DBL_SIGNED long
#  define PRI_BDIGIT_PREFIX "h"
#  define PRI_BDIGIT_DBL_PREFIX "l"
# else
#  define BDIGIT unsigned short
#  define SIZEOF_BDIGIT (SIZEOF_LONG/2)
#  define SIZEOF_ACTUAL_BDIGIT SIZEOF_LONG
#  define BDIGIT_DBL unsigned long
#  define BDIGIT_DBL_SIGNED long
#  define PRI_BDIGIT_PREFIX "h"
#  define PRI_BDIGIT_DBL_PREFIX "l"
# endif
#endif
#ifndef SIZEOF_ACTUAL_BDIGIT
# define SIZEOF_ACTUAL_BDIGIT SIZEOF_BDIGIT
#endif

#ifdef PRI_BDIGIT_PREFIX
# define PRIdBDIGIT PRI_BDIGIT_PREFIX"d"
# define PRIiBDIGIT PRI_BDIGIT_PREFIX"i"
# define PRIoBDIGIT PRI_BDIGIT_PREFIX"o"
# define PRIuBDIGIT PRI_BDIGIT_PREFIX"u"
# define PRIxBDIGIT PRI_BDIGIT_PREFIX"x"
# define PRIXBDIGIT PRI_BDIGIT_PREFIX"X"
#endif

#ifdef PRI_BDIGIT_DBL_PREFIX
# define PRIdBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"d"
# define PRIiBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"i"
# define PRIoBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"o"
# define PRIuBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"u"
# define PRIxBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"x"
# define PRIXBDIGIT_DBL PRI_BDIGIT_DBL_PREFIX"X"
#endif

#define BIGNUM_EMBED_LEN_NUMBITS 3
#ifndef BIGNUM_EMBED_LEN_MAX
# if (SIZEOF_VALUE*RVALUE_EMBED_LEN_MAX/SIZEOF_ACTUAL_BDIGIT) < (1 << BIGNUM_EMBED_LEN_NUMBITS)-1
#  define BIGNUM_EMBED_LEN_MAX (SIZEOF_VALUE*RVALUE_EMBED_LEN_MAX/SIZEOF_ACTUAL_BDIGIT)
# else
#  define BIGNUM_EMBED_LEN_MAX ((1 << BIGNUM_EMBED_LEN_NUMBITS)-1)
# endif
#endif

struct RBignum {
    struct RBasic basic;
    union {
        struct {
            size_t len;
            BDIGIT *digits;
        } heap;
        BDIGIT ary[BIGNUM_EMBED_LEN_MAX];
    } as;
};
#define BIGNUM_SIGN_BIT ((VALUE)FL_USER1)
/* sign: positive:1, negative:0 */
#define BIGNUM_SIGN(b) ((RBASIC(b)->flags & BIGNUM_SIGN_BIT) != 0)
#define BIGNUM_SET_SIGN(b,sign) \
  ((sign) ? (RBASIC(b)->flags |= BIGNUM_SIGN_BIT) \
          : (RBASIC(b)->flags &= ~BIGNUM_SIGN_BIT))
#define BIGNUM_POSITIVE_P(b) BIGNUM_SIGN(b)
#define BIGNUM_NEGATIVE_P(b) (!BIGNUM_SIGN(b))
#define BIGNUM_NEGATE(b) (RBASIC(b)->flags ^= BIGNUM_SIGN_BIT)

#define BIGNUM_EMBED_FLAG ((VALUE)FL_USER2)
#define BIGNUM_EMBED_LEN_MASK \
    (~(~(VALUE)0U << BIGNUM_EMBED_LEN_NUMBITS) << BIGNUM_EMBED_LEN_SHIFT)
#define BIGNUM_EMBED_LEN_SHIFT \
    (FL_USHIFT+3) /* bit offset of BIGNUM_EMBED_LEN_MASK */
#define BIGNUM_LEN(b) \
    ((RBASIC(b)->flags & BIGNUM_EMBED_FLAG) ? \
     (size_t)((RBASIC(b)->flags >> BIGNUM_EMBED_LEN_SHIFT) & \
              (BIGNUM_EMBED_LEN_MASK >> BIGNUM_EMBED_LEN_SHIFT)) : \
     RBIGNUM(b)->as.heap.len)
/* LSB:BIGNUM_DIGITS(b)[0], MSB:BIGNUM_DIGITS(b)[BIGNUM_LEN(b)-1] */
#define BIGNUM_DIGITS(b) \
    ((RBASIC(b)->flags & BIGNUM_EMBED_FLAG) ? \
     RBIGNUM(b)->as.ary : \
     RBIGNUM(b)->as.heap.digits)
#define BIGNUM_LENINT(b) rb_long2int(BIGNUM_LEN(b))

#define RBIGNUM(obj) (R_CAST(RBignum)(obj))

/* bignum.c */
extern const char ruby_digitmap[];
double rb_big_fdiv_double(VALUE x, VALUE y);
VALUE rb_big_uminus(VALUE x);
VALUE rb_big_hash(VALUE);
VALUE rb_big_odd_p(VALUE);
VALUE rb_big_even_p(VALUE);
size_t rb_big_size(VALUE);
VALUE rb_integer_float_cmp(VALUE x, VALUE y);
VALUE rb_integer_float_eq(VALUE x, VALUE y);
VALUE rb_str_convert_to_inum(VALUE str, int base, int badcheck, int raise_exception);
VALUE rb_big_comp(VALUE x);
VALUE rb_big_aref(VALUE x, VALUE y);
VALUE rb_big_abs(VALUE x);
VALUE rb_big_size_m(VALUE big);
VALUE rb_big_bit_length(VALUE big);
VALUE rb_big_remainder(VALUE x, VALUE y);
VALUE rb_big_gt(VALUE x, VALUE y);
VALUE rb_big_ge(VALUE x, VALUE y);
VALUE rb_big_lt(VALUE x, VALUE y);
VALUE rb_big_le(VALUE x, VALUE y);
VALUE rb_int_powm(int const argc, VALUE * const argv, VALUE const num);

RUBY_SYMBOL_EXPORT_BEGIN
/* bignum.c (export) */
VALUE rb_big_mul_normal(VALUE x, VALUE y);
VALUE rb_big_mul_balance(VALUE x, VALUE y);
VALUE rb_big_mul_karatsuba(VALUE x, VALUE y);
VALUE rb_big_mul_toom3(VALUE x, VALUE y);
VALUE rb_big_sq_fast(VALUE x);
VALUE rb_big_divrem_normal(VALUE x, VALUE y);
VALUE rb_big2str_poweroftwo(VALUE x, int base);
VALUE rb_big2str_generic(VALUE x, int base);
VALUE rb_str2big_poweroftwo(VALUE arg, int base, int badcheck);
VALUE rb_str2big_normal(VALUE arg, int base, int badcheck);
VALUE rb_str2big_karatsuba(VALUE arg, int base, int badcheck);
#if defined(HAVE_LIBGMP) && defined(HAVE_GMP_H)
VALUE rb_big_mul_gmp(VALUE x, VALUE y);
VALUE rb_big_divrem_gmp(VALUE x, VALUE y);
VALUE rb_big2str_gmp(VALUE x, int base);
VALUE rb_str2big_gmp(VALUE arg, int base, int badcheck);
#endif
enum rb_int_parse_flags {
    RB_INT_PARSE_SIGN       = 0x01,
    RB_INT_PARSE_UNDERSCORE = 0x02,
    RB_INT_PARSE_PREFIX     = 0x04,
    RB_INT_PARSE_ALL        = 0x07,
    RB_INT_PARSE_DEFAULT    = 0x07
};
VALUE rb_int_parse_cstr(const char *str, ssize_t len, char **endp, size_t *ndigits, int base, int flags);
RUBY_SYMBOL_EXPORT_END

#endif /* INTERNAL_BIGNUM_H */