int mpfr_mul_2si (mpfr_ptr y, mpfr_srcptr x, long int n, mpfr_rnd_t rnd_mode) { int inexact; MPFR_LOG_FUNC (("x[%#R]=%R n=%ld rnd=%d", x, x, n, rnd_mode), ("y[%#R]=%R inexact=%d", y, y, inexact)); if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x))) return mpfr_set (y, x, rnd_mode); else { mpfr_exp_t exp = MPFR_GET_EXP (x); MPFR_SETRAW (inexact, y, x, exp, rnd_mode); if (MPFR_UNLIKELY( n > 0 && (__gmpfr_emax < MPFR_EMIN_MIN + n || exp > __gmpfr_emax - n))) return mpfr_overflow (y, rnd_mode, MPFR_SIGN(y)); else if (MPFR_UNLIKELY(n < 0 && (__gmpfr_emin > MPFR_EMAX_MAX + n || exp < __gmpfr_emin - n))) { if (rnd_mode == MPFR_RNDN && (__gmpfr_emin > MPFR_EMAX_MAX + (n + 1) || exp < __gmpfr_emin - (n + 1) || (inexact >= 0 && mpfr_powerof2_raw (y)))) rnd_mode = MPFR_RNDZ; return mpfr_underflow (y, rnd_mode, MPFR_SIGN(y)); } MPFR_SET_EXP (y, exp + n); } MPFR_RET (inexact); }
int mpfr_div_2ui (mpfr_ptr y, mpfr_srcptr x, unsigned long n, mpfr_rnd_t rnd_mode) { int inexact; MPFR_LOG_FUNC (("x[%#R]=%R n=%lu rnd=%d", x, x, n, rnd_mode), ("y[%#R]=%R inexact=%d", y, y, inexact)); if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x))) return mpfr_set (y, x, rnd_mode); else { mpfr_exp_t exp = MPFR_GET_EXP (x); mpfr_uexp_t diffexp; MPFR_SETRAW (inexact, y, x, exp, rnd_mode); diffexp = (mpfr_uexp_t) exp - (mpfr_uexp_t) (__gmpfr_emin - 1); if (MPFR_UNLIKELY (n >= diffexp)) /* exp - n <= emin - 1 */ { if (rnd_mode == MPFR_RNDN && (n > diffexp || (inexact >= 0 && mpfr_powerof2_raw (y)))) rnd_mode = MPFR_RNDZ; return mpfr_underflow (y, rnd_mode, MPFR_SIGN (y)); } /* exp - n >= emin (no underflow, no integer overflow) */ while (n > LONG_MAX) { n -= LONG_MAX; exp -= LONG_MAX; /* note: signed values */ } MPFR_SET_EXP (y, exp - (long) n); } MPFR_RET (inexact); }
MPFR_HOT_FUNCTION_ATTR int mpfr_div_2si (mpfr_ptr y, mpfr_srcptr x, long int n, mpfr_rnd_t rnd_mode) { int inexact; MPFR_LOG_FUNC (("x[%Pu]=%.*Rg n=%ld rnd=%d", mpfr_get_prec(x), mpfr_log_prec, x, n, rnd_mode), ("y[%Pu]=%.*Rg inexact=%d", mpfr_get_prec(y), mpfr_log_prec, y, inexact)); if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x))) return mpfr_set (y, x, rnd_mode); else { mpfr_exp_t exp = MPFR_GET_EXP (x); MPFR_SETRAW (inexact, y, x, exp, rnd_mode); if (MPFR_UNLIKELY( n > 0 && (__gmpfr_emin > MPFR_EMAX_MAX - n || exp < __gmpfr_emin + n)) ) { if (rnd_mode == MPFR_RNDN && (__gmpfr_emin > MPFR_EMAX_MAX - (n - 1) || exp < __gmpfr_emin + (n - 1) || ((MPFR_IS_NEG (y) ? inexact <= 0 : inexact >= 0) && mpfr_powerof2_raw (y)))) rnd_mode = MPFR_RNDZ; return mpfr_underflow (y, rnd_mode, MPFR_SIGN(y)); } else if (MPFR_UNLIKELY(n <= 0 && (__gmpfr_emax < MPFR_EMIN_MIN - n || exp > __gmpfr_emax + n)) ) return mpfr_overflow (y, rnd_mode, MPFR_SIGN(y)); MPFR_SET_EXP (y, exp - n); } MPFR_RET (inexact); }