/*
* Set f to z, choosing the smallest precision for f
* so that z = f*(2^BPML)*zs*2^(RetVal)
*/
static int
set_z (mpfr_ptr f, mpz_srcptr z, mp_size_t *zs)
{
mp_limb_t *p;
mp_size_t s;
int c;
mp_prec_t pf;
MPFR_ASSERTD (mpz_sgn (z) != 0);
/* Remove useless ending 0 */
for (p = PTR (z), s = *zs = ABS (SIZ (z)) ; *p == 0; p++, s--)
MPFR_ASSERTD (s >= 0);
/* Get working precision */
count_leading_zeros (c, p[s-1]);
pf = s * BITS_PER_MP_LIMB - c;
if (pf < MPFR_PREC_MIN)
pf = MPFR_PREC_MIN;
mpfr_init2 (f, pf);
/* Copy Mantissa */
if (MPFR_LIKELY (c))
mpn_lshift (MPFR_MANT (f), p, s, c);
else
MPN_COPY (MPFR_MANT (f), p, s);
MPFR_SET_SIGN (f, mpz_sgn (z));
MPFR_SET_EXP (f, 0);
return -c;
}
void
mpfr_custom_init_set (mpfr_ptr x, int kind, mp_exp_t exp,
mp_prec_t prec, void *mantissa)
{
mpfr_kind_t t;
int s;
mp_exp_t e;
if (kind >= 0)
{
t = (mpfr_kind_t) kind;
s = MPFR_SIGN_POS;
}
else
{
t = (mpfr_kind_t) -kind;
s = MPFR_SIGN_NEG;
}
MPFR_ASSERTD (t <= MPFR_REGULAR_KIND);
e = MPFR_LIKELY (t == MPFR_REGULAR_KIND) ? exp :
MPFR_UNLIKELY (t == MPFR_NAN_KIND) ? MPFR_EXP_NAN :
MPFR_UNLIKELY (t == MPFR_INF_KIND) ? MPFR_EXP_INF : MPFR_EXP_ZERO;
MPFR_PREC (x) = prec;
MPFR_SET_SIGN (x, s);
MPFR_EXP (x) = e;
MPFR_MANT (x) = (mp_limb_t*) mantissa;
return;
}
MPFR_COLD_FUNCTION_ATTR int
mpfr_overflow (mpfr_ptr x, mpfr_rnd_t rnd_mode, int sign)
{
int inex;
MPFR_LOG_FUNC
(("x[%Pu]=%.*Rg rnd=%d sign=%d", mpfr_get_prec (x), mpfr_log_prec, x,
rnd_mode, sign),
("x[%Pu]=%.*Rg", mpfr_get_prec (x), mpfr_log_prec, x));
MPFR_ASSERT_SIGN (sign);
if (MPFR_IS_LIKE_RNDZ(rnd_mode, sign < 0))
{
mpfr_setmax (x, __gmpfr_emax);
inex = -1;
}
else
{
MPFR_SET_INF(x);
inex = 1;
}
MPFR_SET_SIGN(x, sign);
__gmpfr_flags |= MPFR_FLAGS_INEXACT | MPFR_FLAGS_OVERFLOW;
return sign > 0 ? inex : -inex;
}
int
mpfr_set_si_2exp (mpfr_ptr x, long i, mp_exp_t e, mp_rnd_t rnd_mode)
{
if (i == 0)
{
MPFR_SET_ZERO (x);
MPFR_SET_POS (x);
MPFR_RET (0);
}
else
{
mp_size_t xn;
unsigned int cnt, nbits;
mp_limb_t ai, *xp;
int inex = 0;
/* FIXME: support int limbs (e.g. 16-bit limbs on 16-bit proc) */
ai = SAFE_ABS (unsigned long, i);
MPFR_ASSERTN (SAFE_ABS (unsigned long, i) == ai);
/* Position of the highest limb */
xn = (MPFR_PREC (x) - 1) / BITS_PER_MP_LIMB;
count_leading_zeros (cnt, ai);
MPFR_ASSERTD (cnt < BITS_PER_MP_LIMB); /* OK since i != 0 */
xp = MPFR_MANT(x);
xp[xn] = ai << cnt;
/* Zero the xn lower limbs. */
MPN_ZERO(xp, xn);
MPFR_SET_SIGN (x, i < 0 ? MPFR_SIGN_NEG : MPFR_SIGN_POS);
nbits = BITS_PER_MP_LIMB - cnt;
e += nbits; /* exponent _before_ the rounding */
/* round if MPFR_PREC(x) smaller than length of i */
if (MPFR_UNLIKELY (MPFR_PREC (x) < nbits) &&
MPFR_UNLIKELY (mpfr_round_raw (xp + xn, xp + xn, nbits, i < 0,
MPFR_PREC (x), rnd_mode, &inex)))
{
e++;
xp[xn] = MPFR_LIMB_HIGHBIT;
}
MPFR_CLEAR_FLAGS (x);
MPFR_EXP (x) = e;
return mpfr_check_range (x, inex, rnd_mode);
}
}
int
mpfr_overflow (mpfr_ptr x, mpfr_rnd_t rnd_mode, int sign)
{
int inex;
MPFR_ASSERT_SIGN(sign);
if (MPFR_IS_LIKE_RNDZ(rnd_mode, sign < 0))
{
mpfr_setmax (x, __gmpfr_emax);
inex = -1;
}
else
{
MPFR_SET_INF(x);
inex = 1;
}
MPFR_SET_SIGN(x,sign);
__gmpfr_flags |= MPFR_FLAGS_INEXACT | MPFR_FLAGS_OVERFLOW;
return sign > 0 ? inex : -inex;
}
int
mpfr_overflow (mpfr_ptr x, mp_rnd_t rnd_mode, int sign)
{
int inex;
MPFR_ASSERT_SIGN(sign);
MPFR_CLEAR_FLAGS(x);
if (rnd_mode == GMP_RNDN
|| MPFR_IS_RNDUTEST_OR_RNDDNOTTEST(rnd_mode, sign > 0))
{
MPFR_SET_INF(x);
inex = 1;
}
else
{
mpfr_setmax (x, __gmpfr_emax);
inex = -1;
}
MPFR_SET_SIGN(x,sign);
__gmpfr_flags |= MPFR_FLAGS_INEXACT | MPFR_FLAGS_OVERFLOW;
return sign > 0 ? inex : -inex;
}
int
mpfr_underflow (mpfr_ptr x, mp_rnd_t rnd_mode, int sign)
{
int inex;
MPFR_ASSERT_SIGN (sign);
if (rnd_mode == GMP_RNDN
|| MPFR_IS_RNDUTEST_OR_RNDDNOTTEST(rnd_mode, MPFR_IS_POS_SIGN (sign)))
{
mpfr_setmin (x, __gmpfr_emin);
inex = 1;
}
else
{
MPFR_SET_ZERO(x);
inex = -1;
}
MPFR_SET_SIGN(x, sign);
__gmpfr_flags |= MPFR_FLAGS_INEXACT | MPFR_FLAGS_UNDERFLOW;
return sign > 0 ? inex : -inex;
}
static void
check_cmp (int argc, char *argv[])
{
mpfr_t x, y;
int n, k;
mpfr_inits2 (53, x, y, (mpfr_ptr) 0);
mpfr_set_ui(x, 1, MPFR_RNDN);
(mpfr_abs) (x, x, MPFR_RNDN);
if (mpfr_cmp_ui (x, 1))
{
printf ("Error in mpfr_abs(1.0)\n");
exit (1);
}
mpfr_set_si(x, -1, MPFR_RNDN);
mpfr_abs(x, x, MPFR_RNDN);
if (mpfr_cmp_ui (x, 1))
{
printf ("Error in mpfr_abs(1.0)\n");
exit (1);
}
mpfr_set_si(x, -1, MPFR_RNDN);
mpfr_abs(x, x, MPFR_RNDN);
if (mpfr_cmp_ui (x, 1))
{
printf ("Error in mpfr_abs(-1.0)\n");
exit (1);
}
mpfr_set_inf (x, 1);
mpfr_abs (x, x, MPFR_RNDN);
if (!mpfr_inf_p(x) || (mpfr_sgn(x) <= 0))
{
printf ("Error in mpfr_abs(Inf).\n");
exit (1);
}
mpfr_set_inf (x, -1);
mpfr_abs (x, x, MPFR_RNDN);
if (!mpfr_inf_p(x) || (mpfr_sgn(x) <= 0))
{
printf ("Error in mpfr_abs(-Inf).\n");
exit (1);
}
MPFR_SET_NAN(x);
mpfr_abs (x, x, MPFR_RNDN);
if (!MPFR_IS_NAN(x))
{
printf ("Error in mpfr_abs(NAN).\n");
exit (1);
}
n = (argc==1) ? 25000 : atoi(argv[1]);
for (k = 1; k <= n; k++)
{
mpfr_rnd_t rnd;
int sign = SIGN_RAND ();
mpfr_urandomb (x, RANDS);
MPFR_SET_SIGN (x, sign);
rnd = RND_RAND ();
mpfr_abs (y, x, rnd);
MPFR_SET_POS (x);
if (mpfr_cmp (x, y))
{
printf ("Mismatch for sign=%d and x=", sign);
mpfr_print_binary (x);
printf ("\nResults=");
mpfr_print_binary (y);
putchar ('\n');
exit (1);
}
}
mpfr_clears (x, y, (mpfr_ptr) 0);
}
/* set f to the rational q */
int
mpfr_set_q (mpfr_ptr f, mpq_srcptr q, mp_rnd_t rnd)
{
mpz_srcptr num, den;
mpfr_t n, d;
int inexact;
int cn, cd;
long shift;
mp_size_t sn, sd;
MPFR_SAVE_EXPO_DECL (expo);
num = mpq_numref (q);
den = mpq_denref (q);
/* NAN and INF for mpq are not really documented, but could be found */
if (MPFR_UNLIKELY (mpz_sgn (num) == 0))
{
if (MPFR_UNLIKELY (mpz_sgn (den) == 0))
{
MPFR_SET_NAN (f);
MPFR_RET_NAN;
}
else
{
MPFR_SET_ZERO (f);
MPFR_SET_POS (f);
MPFR_RET (0);
}
}
if (MPFR_UNLIKELY (mpz_sgn (den) == 0))
{
MPFR_SET_INF (f);
MPFR_SET_SIGN (f, mpz_sgn (num));
MPFR_RET (0);
}
MPFR_SAVE_EXPO_MARK (expo);
cn = set_z (n, num, &sn);
cd = set_z (d, den, &sd);
sn -= sd;
if (MPFR_UNLIKELY (sn > MPFR_EMAX_MAX / BITS_PER_MP_LIMB))
{
inexact = mpfr_overflow (f, rnd, MPFR_SIGN (f));
goto end;
}
if (MPFR_UNLIKELY (sn < MPFR_EMIN_MIN / BITS_PER_MP_LIMB -1))
{
if (rnd == GMP_RNDN)
rnd = GMP_RNDZ;
inexact = mpfr_underflow (f, rnd, MPFR_SIGN (f));
goto end;
}
inexact = mpfr_div (f, n, d, rnd);
shift = BITS_PER_MP_LIMB*sn+cn-cd;
MPFR_ASSERTD (shift == BITS_PER_MP_LIMB*sn+cn-cd);
cd = mpfr_mul_2si (f, f, shift, rnd);
MPFR_SAVE_EXPO_FREE (expo);
if (MPFR_UNLIKELY (cd != 0))
inexact = cd;
else
inexact = mpfr_check_range (f, inexact, rnd);
end:
mpfr_clear (d);
mpfr_clear (n);
return inexact;
}
int
mpfr_sub (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
{
MPFR_LOG_FUNC (("b[%#R]=%R c[%#R]=%R rnd=%d", b, b, c, c, rnd_mode),
("a[%#R]=%R", a, a));
if (MPFR_ARE_SINGULAR (b,c))
{
if (MPFR_IS_NAN (b) || MPFR_IS_NAN (c))
{
MPFR_SET_NAN (a);
MPFR_RET_NAN;
}
else if (MPFR_IS_INF (b))
{
if (!MPFR_IS_INF (c) || MPFR_SIGN (b) != MPFR_SIGN(c))
{
MPFR_SET_INF (a);
MPFR_SET_SAME_SIGN (a, b);
MPFR_RET (0); /* exact */
}
else
{
MPFR_SET_NAN (a); /* Inf - Inf */
MPFR_RET_NAN;
}
}
else if (MPFR_IS_INF (c))
{
MPFR_SET_INF (a);
MPFR_SET_OPPOSITE_SIGN (a, c);
MPFR_RET (0); /* exact */
}
else if (MPFR_IS_ZERO (b))
{
if (MPFR_IS_ZERO (c))
{
int sign = rnd_mode != MPFR_RNDD
? ((MPFR_IS_NEG(b) && MPFR_IS_POS(c)) ? -1 : 1)
: ((MPFR_IS_POS(b) && MPFR_IS_NEG(c)) ? 1 : -1);
MPFR_SET_SIGN (a, sign);
MPFR_SET_ZERO (a);
MPFR_RET(0); /* 0 - 0 is exact */
}
else
return mpfr_neg (a, c, rnd_mode);
}
else
{
MPFR_ASSERTD (MPFR_IS_ZERO (c));
return mpfr_set (a, b, rnd_mode);
}
}
MPFR_ASSERTD (MPFR_IS_PURE_FP (b) && MPFR_IS_PURE_FP (c));
if (MPFR_LIKELY (MPFR_SIGN (b) == MPFR_SIGN (c)))
{ /* signs are equal, it's a real subtraction */
if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
&& MPFR_PREC (b) == MPFR_PREC (c)))
return mpfr_sub1sp (a, b, c, rnd_mode);
else
return mpfr_sub1 (a, b, c, rnd_mode);
}
else
{ /* signs differ, it's an addition */
if (MPFR_GET_EXP (b) < MPFR_GET_EXP (c))
{ /* exchange rounding modes toward +/- infinity */
int inexact;
rnd_mode = MPFR_INVERT_RND (rnd_mode);
if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
&& MPFR_PREC (b) == MPFR_PREC (c)))
inexact = mpfr_add1sp (a, c, b, rnd_mode);
else
inexact = mpfr_add1 (a, c, b, rnd_mode);
MPFR_CHANGE_SIGN (a);
return -inexact;
}
else
{
if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
&& MPFR_PREC (b) == MPFR_PREC (c)))
return mpfr_add1sp (a, b, c, rnd_mode);
else
return mpfr_add1 (a, b, c, rnd_mode);
}
}
}
int
mpfr_div (mpfr_ptr q, mpfr_srcptr u, mpfr_srcptr v, mp_rnd_t rnd_mode)
{
mp_srcptr up, vp, bp;
mp_size_t usize, vsize;
mp_ptr ap, qp, rp;
mp_size_t asize, bsize, qsize, rsize;
mp_exp_t qexp;
mp_size_t err, k;
mp_limb_t tonearest;
int inex, sh, can_round = 0, sign_quotient;
unsigned int cc = 0, rw;
TMP_DECL (marker);
/**************************************************************************
* *
* This part of the code deals with special cases *
* *
**************************************************************************/
if (MPFR_ARE_SINGULAR(u,v))
{
if (MPFR_IS_NAN(u) || MPFR_IS_NAN(v))
{
MPFR_SET_NAN(q);
MPFR_RET_NAN;
}
sign_quotient = MPFR_MULT_SIGN( MPFR_SIGN(u) , MPFR_SIGN(v) );
MPFR_SET_SIGN(q, sign_quotient);
if (MPFR_IS_INF(u))
{
if (MPFR_IS_INF(v))
{
MPFR_SET_NAN(q);
MPFR_RET_NAN;
}
else
{
MPFR_SET_INF(q);
MPFR_RET(0);
}
}
else if (MPFR_IS_INF(v))
{
MPFR_SET_ZERO(q);
MPFR_RET(0);
}
else if (MPFR_IS_ZERO(v))
{
if (MPFR_IS_ZERO(u))
{
MPFR_SET_NAN(q);
MPFR_RET_NAN;
}
else
{
MPFR_SET_INF(q);
MPFR_RET(0);
}
}
else
{
MPFR_ASSERTD(MPFR_IS_ZERO(u));
MPFR_SET_ZERO(q);
MPFR_RET(0);
}
}
MPFR_CLEAR_FLAGS(q);
/**************************************************************************
* *
* End of the part concerning special values. *
* *
**************************************************************************/
sign_quotient = MPFR_MULT_SIGN( MPFR_SIGN(u) , MPFR_SIGN(v) );
up = MPFR_MANT(u);
vp = MPFR_MANT(v);
MPFR_SET_SIGN(q, sign_quotient);
TMP_MARK (marker);
usize = MPFR_LIMB_SIZE(u);
vsize = MPFR_LIMB_SIZE(v);
/**************************************************************************
* *
* First try to use only part of u, v. If this is not sufficient, *
* use the full u and v, to avoid long computations eg. in the case *
* u = v. *
* *
**************************************************************************/
/* The dividend is a, length asize. The divisor is b, length bsize. */
qsize = (MPFR_PREC(q) + 3) / BITS_PER_MP_LIMB + 1;
/* in case PREC(q)=PREC(v), then vsize=qsize with probability 1-4/b
where b is the number of bits per limb */
if (MPFR_LIKELY(vsize <= qsize))
{
bsize = vsize;
bp = vp;
}
else /* qsize < vsize: take only the qsize high limbs of the divisor */
{
bsize = qsize;
bp = (mp_srcptr) vp + (vsize - qsize);
}
/* we have {bp, bsize} * (1 + errb) = (true divisor)
with 0 <= errb < 2^(-qsize*BITS_PER_MP_LIMB+1) */
asize = bsize + qsize;
ap = (mp_ptr) TMP_ALLOC (asize * BYTES_PER_MP_LIMB);
/* if all arguments have same precision, then asize will be about 2*usize */
if (MPFR_LIKELY(asize > usize))
{
/* copy u into the high limbs of {ap, asize}, and pad with zeroes */
/* FIXME: could we copy only the qsize high limbs of the dividend? */
MPN_COPY (ap + asize - usize, up, usize);
MPN_ZERO (ap, asize - usize);
}
else /* truncate the high asize limbs of u into {ap, asize} */
MPN_COPY (ap, up + usize - asize, asize);
/* we have {ap, asize} = (true dividend) * (1 - erra)
with 0 <= erra < 2^(-asize*BITS_PER_MP_LIMB).
This {ap, asize} / {bp, bsize} =
(true dividend) / (true divisor) * (1 - erra) (1 + errb) */
/* Allocate limbs for quotient and remainder. */
qp = (mp_ptr) TMP_ALLOC ((qsize + 1) * BYTES_PER_MP_LIMB);
rp = (mp_ptr) TMP_ALLOC (bsize * BYTES_PER_MP_LIMB);
rsize = bsize;
mpn_tdiv_qr (qp, rp, 0, ap, asize, bp, bsize);
sh = - (int) qp[qsize];
/* since u and v are normalized, sh is 0 or -1 */
/* we have {qp, qsize + 1} = {ap, asize} / {bp, bsize} (1 - errq)
with 0 <= errq < 2^(-qsize*BITS_PER_MP_LIMB+1+sh)
thus {qp, qsize + 1} =
(true dividend) / (true divisor) * (1 - erra) (1 + errb) (1 - errq).
In fact, since the truncated dividend and {rp, bsize} do not overlap,
we have: {qp, qsize + 1} =
(true dividend) / (true divisor) * (1 - erra') (1 + errb)
where 0 <= erra' < 2^(-qsize*BITS_PER_MP_LIMB+sh) */
/* Estimate number of correct bits. */
err = qsize * BITS_PER_MP_LIMB;
/* We want to check if rounding is possible, but without normalizing
because we might have to divide again if rounding is impossible, or
if the result might be exact. We have however to mimic normalization */
/*
To detect asap if the result is inexact, so as to avoid doing the
division completely, we perform the following check :
- if rnd_mode != GMP_RNDN, and the result is exact, we are unable
to round simultaneously to zero and to infinity ;
- if rnd_mode == GMP_RNDN, and if we can round to zero with one extra
bit of precision, we can decide rounding. Hence in that case, check
as in the case of GMP_RNDN, with one extra bit. Note that in the case
of close to even rounding we shall do the division completely, but
this is necessary anyway : we need to know whether this is really
even rounding or not.
*/
if (MPFR_UNLIKELY(asize < usize || bsize < vsize))
{
{
mp_rnd_t rnd_mode1, rnd_mode2;
mp_exp_t tmp_exp;
mp_prec_t tmp_prec;
if (bsize < vsize)
err -= 2; /* divisor is truncated */
#if 0 /* commented this out since the truncation of the dividend is already
taken into account in {rp, bsize}, which does not overlap with the
neglected part of the dividend */
else if (asize < usize)
err --; /* dividend is truncated */
#endif
if (MPFR_LIKELY(rnd_mode == GMP_RNDN))
{
rnd_mode1 = GMP_RNDZ;
rnd_mode2 = MPFR_IS_POS_SIGN(sign_quotient) ? GMP_RNDU : GMP_RNDD;
sh++;
}
else
{
rnd_mode1 = rnd_mode;
switch (rnd_mode)
{
case GMP_RNDU:
rnd_mode2 = GMP_RNDD; break;
case GMP_RNDD:
rnd_mode2 = GMP_RNDU; break;
default:
rnd_mode2 = MPFR_IS_POS_SIGN(sign_quotient) ?
GMP_RNDU : GMP_RNDD;
break;
}
}
tmp_exp = err + sh + BITS_PER_MP_LIMB;
tmp_prec = MPFR_PREC(q) + sh + BITS_PER_MP_LIMB;
can_round =
mpfr_can_round_raw (qp, qsize + 1, sign_quotient, tmp_exp,
GMP_RNDN, rnd_mode1, tmp_prec)
& mpfr_can_round_raw (qp, qsize + 1, sign_quotient, tmp_exp,
GMP_RNDN, rnd_mode2, tmp_prec);
/* restore original value of sh, i.e. sh = - qp[qsize] */
sh -= (rnd_mode == GMP_RNDN);
}
int
mpfr_add (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
{
MPFR_LOG_FUNC (("b[%#R]=%R c[%#R]=%R rnd=%d", b, b, c, c, rnd_mode),
("a[%#R]=%R", a, a));
if (MPFR_ARE_SINGULAR(b,c))
{
if (MPFR_IS_NAN(b) || MPFR_IS_NAN(c))
{
MPFR_SET_NAN(a);
MPFR_RET_NAN;
}
/* neither b nor c is NaN here */
else if (MPFR_IS_INF(b))
{
if (!MPFR_IS_INF(c) || MPFR_SIGN(b) == MPFR_SIGN(c))
{
MPFR_SET_INF(a);
MPFR_SET_SAME_SIGN(a, b);
MPFR_RET(0); /* exact */
}
else
{
MPFR_SET_NAN(a);
MPFR_RET_NAN;
}
}
else if (MPFR_IS_INF(c))
{
MPFR_SET_INF(a);
MPFR_SET_SAME_SIGN(a, c);
MPFR_RET(0); /* exact */
}
/* now either b or c is zero */
else if (MPFR_IS_ZERO(b))
{
if (MPFR_IS_ZERO(c))
{
/* for round away, we take the same convention for 0 + 0
as for round to zero or to nearest: it always gives +0,
except (-0) + (-0) = -0. */
MPFR_SET_SIGN(a,
(rnd_mode != MPFR_RNDD ?
((MPFR_IS_NEG(b) && MPFR_IS_NEG(c)) ? -1 : 1) :
((MPFR_IS_POS(b) && MPFR_IS_POS(c)) ? 1 : -1)));
MPFR_SET_ZERO(a);
MPFR_RET(0); /* 0 + 0 is exact */
}
return mpfr_set (a, c, rnd_mode);
}
else
{
MPFR_ASSERTD(MPFR_IS_ZERO(c));
return mpfr_set (a, b, rnd_mode);
}
}
MPFR_ASSERTD(MPFR_IS_PURE_FP(b) && MPFR_IS_PURE_FP(c));
if (MPFR_UNLIKELY(MPFR_SIGN(b) != MPFR_SIGN(c)))
{ /* signs differ, it's a subtraction */
if (MPFR_LIKELY(MPFR_PREC(a) == MPFR_PREC(b)
&& MPFR_PREC(b) == MPFR_PREC(c)))
return mpfr_sub1sp(a,b,c,rnd_mode);
else
return mpfr_sub1(a, b, c, rnd_mode);
}
else
{ /* signs are equal, it's an addition */
if (MPFR_LIKELY(MPFR_PREC(a) == MPFR_PREC(b)
&& MPFR_PREC(b) == MPFR_PREC(c)))
if (MPFR_GET_EXP(b) < MPFR_GET_EXP(c))
return mpfr_add1sp(a, c, b, rnd_mode);
else
return mpfr_add1sp(a, b, c, rnd_mode);
else
if (MPFR_GET_EXP(b) < MPFR_GET_EXP(c))
return mpfr_add1(a, c, b, rnd_mode);
else
return mpfr_add1(a, b, c, rnd_mode);
}
}
static int
mpfr_mul3 (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
{
/* Old implementation */
int sign_product, cc, inexact;
mpfr_exp_t ax;
mp_limb_t *tmp;
mp_limb_t b1;
mpfr_prec_t bq, cq;
mp_size_t bn, cn, tn, k;
MPFR_TMP_DECL(marker);
/* deal with special cases */
if (MPFR_ARE_SINGULAR(b,c))
{
if (MPFR_IS_NAN(b) || MPFR_IS_NAN(c))
{
MPFR_SET_NAN(a);
MPFR_RET_NAN;
}
sign_product = MPFR_MULT_SIGN( MPFR_SIGN(b) , MPFR_SIGN(c) );
if (MPFR_IS_INF(b))
{
if (MPFR_IS_INF(c) || MPFR_NOTZERO(c))
{
MPFR_SET_SIGN(a,sign_product);
MPFR_SET_INF(a);
MPFR_RET(0); /* exact */
}
else
{
MPFR_SET_NAN(a);
MPFR_RET_NAN;
}
}
else if (MPFR_IS_INF(c))
{
if (MPFR_NOTZERO(b))
{
MPFR_SET_SIGN(a, sign_product);
MPFR_SET_INF(a);
MPFR_RET(0); /* exact */
}
else
{
MPFR_SET_NAN(a);
MPFR_RET_NAN;
}
}
else
{
MPFR_ASSERTD(MPFR_IS_ZERO(b) || MPFR_IS_ZERO(c));
MPFR_SET_SIGN(a, sign_product);
MPFR_SET_ZERO(a);
MPFR_RET(0); /* 0 * 0 is exact */
}
}
sign_product = MPFR_MULT_SIGN( MPFR_SIGN(b) , MPFR_SIGN(c) );
ax = MPFR_GET_EXP (b) + MPFR_GET_EXP (c);
bq = MPFR_PREC(b);
cq = MPFR_PREC(c);
MPFR_ASSERTD(bq+cq > bq); /* PREC_MAX is /2 so no integer overflow */
bn = (bq+GMP_NUMB_BITS-1)/GMP_NUMB_BITS; /* number of limbs of b */
cn = (cq+GMP_NUMB_BITS-1)/GMP_NUMB_BITS; /* number of limbs of c */
k = bn + cn; /* effective nb of limbs used by b*c (= tn or tn+1) below */
tn = (bq + cq + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS;
/* <= k, thus no int overflow */
MPFR_ASSERTD(tn <= k);
/* Check for no size_t overflow*/
MPFR_ASSERTD((size_t) k <= ((size_t) -1) / BYTES_PER_MP_LIMB);
MPFR_TMP_MARK(marker);
tmp = (mp_limb_t *) MPFR_TMP_ALLOC((size_t) k * BYTES_PER_MP_LIMB);
/* multiplies two mantissa in temporary allocated space */
b1 = (MPFR_LIKELY(bn >= cn)) ?
mpn_mul (tmp, MPFR_MANT(b), bn, MPFR_MANT(c), cn)
: mpn_mul (tmp, MPFR_MANT(c), cn, MPFR_MANT(b), bn);
/* now tmp[0]..tmp[k-1] contains the product of both mantissa,
with tmp[k-1]>=2^(GMP_NUMB_BITS-2) */
b1 >>= GMP_NUMB_BITS - 1; /* msb from the product */
/* if the mantissas of b and c are uniformly distributed in ]1/2, 1],
then their product is in ]1/4, 1/2] with probability 2*ln(2)-1 ~ 0.386
and in [1/2, 1] with probability 2-2*ln(2) ~ 0.614 */
tmp += k - tn;
if (MPFR_UNLIKELY(b1 == 0))
mpn_lshift (tmp, tmp, tn, 1); /* tn <= k, so no stack corruption */
cc = mpfr_round_raw (MPFR_MANT (a), tmp, bq + cq,
MPFR_IS_NEG_SIGN(sign_product),
MPFR_PREC (a), rnd_mode, &inexact);
/* cc = 1 ==> result is a power of two */
if (MPFR_UNLIKELY(cc))
MPFR_MANT(a)[MPFR_LIMB_SIZE(a)-1] = MPFR_LIMB_HIGHBIT;
MPFR_TMP_FREE(marker);
{
mpfr_exp_t ax2 = ax + (mpfr_exp_t) (b1 - 1 + cc);
if (MPFR_UNLIKELY( ax2 > __gmpfr_emax))
return mpfr_overflow (a, rnd_mode, sign_product);
if (MPFR_UNLIKELY( ax2 < __gmpfr_emin))
{
/* In the rounding to the nearest mode, if the exponent of the exact
result (i.e. before rounding, i.e. without taking cc into account)
is < __gmpfr_emin - 1 or the exact result is a power of 2 (i.e. if
both arguments are powers of 2), then round to zero. */
if (rnd_mode == MPFR_RNDN &&
(ax + (mpfr_exp_t) b1 < __gmpfr_emin ||
(mpfr_powerof2_raw (b) && mpfr_powerof2_raw (c))))
rnd_mode = MPFR_RNDZ;
return mpfr_underflow (a, rnd_mode, sign_product);
}
MPFR_SET_EXP (a, ax2);
MPFR_SET_SIGN(a, sign_product);
}
MPFR_RET (inexact);
}
int
mpfr_mul (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
{
int sign, inexact;
mpfr_exp_t ax, ax2;
mp_limb_t *tmp;
mp_limb_t b1;
mpfr_prec_t bq, cq;
mp_size_t bn, cn, tn, k;
MPFR_TMP_DECL (marker);
MPFR_LOG_FUNC (("b[%#R]=%R c[%#R]=%R rnd=%d", b, b, c, c, rnd_mode),
("a[%#R]=%R inexact=%d", a, a, inexact));
/* deal with special cases */
if (MPFR_ARE_SINGULAR (b, c))
{
if (MPFR_IS_NAN (b) || MPFR_IS_NAN (c))
{
MPFR_SET_NAN (a);
MPFR_RET_NAN;
}
sign = MPFR_MULT_SIGN (MPFR_SIGN (b), MPFR_SIGN (c));
if (MPFR_IS_INF (b))
{
if (!MPFR_IS_ZERO (c))
{
MPFR_SET_SIGN (a, sign);
MPFR_SET_INF (a);
MPFR_RET (0);
}
else
{
MPFR_SET_NAN (a);
MPFR_RET_NAN;
}
}
else if (MPFR_IS_INF (c))
{
if (!MPFR_IS_ZERO (b))
{
MPFR_SET_SIGN (a, sign);
MPFR_SET_INF (a);
MPFR_RET(0);
}
else
{
MPFR_SET_NAN (a);
MPFR_RET_NAN;
}
}
else
{
MPFR_ASSERTD (MPFR_IS_ZERO(b) || MPFR_IS_ZERO(c));
MPFR_SET_SIGN (a, sign);
MPFR_SET_ZERO (a);
MPFR_RET (0);
}
}
sign = MPFR_MULT_SIGN (MPFR_SIGN (b), MPFR_SIGN (c));
ax = MPFR_GET_EXP (b) + MPFR_GET_EXP (c);
/* Note: the exponent of the exact result will be e = bx + cx + ec with
ec in {-1,0,1} and the following assumes that e is representable. */
/* FIXME: Useful since we do an exponent check after ?
* It is useful iff the precision is big, there is an overflow
* and we are doing further mults...*/
#ifdef HUGE
if (MPFR_UNLIKELY (ax > __gmpfr_emax + 1))
return mpfr_overflow (a, rnd_mode, sign);
if (MPFR_UNLIKELY (ax < __gmpfr_emin - 2))
return mpfr_underflow (a, rnd_mode == MPFR_RNDN ? MPFR_RNDZ : rnd_mode,
sign);
#endif
bq = MPFR_PREC (b);
cq = MPFR_PREC (c);
MPFR_ASSERTD (bq+cq > bq); /* PREC_MAX is /2 so no integer overflow */
bn = (bq+GMP_NUMB_BITS-1)/GMP_NUMB_BITS; /* number of limbs of b */
cn = (cq+GMP_NUMB_BITS-1)/GMP_NUMB_BITS; /* number of limbs of c */
k = bn + cn; /* effective nb of limbs used by b*c (= tn or tn+1) below */
tn = (bq + cq + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS;
MPFR_ASSERTD (tn <= k); /* tn <= k, thus no int overflow */
/* Check for no size_t overflow*/
MPFR_ASSERTD ((size_t) k <= ((size_t) -1) / BYTES_PER_MP_LIMB);
MPFR_TMP_MARK (marker);
tmp = (mp_limb_t *) MPFR_TMP_ALLOC ((size_t) k * BYTES_PER_MP_LIMB);
/* multiplies two mantissa in temporary allocated space */
if (MPFR_UNLIKELY (bn < cn))
{
mpfr_srcptr z = b;
mp_size_t zn = bn;
b = c;
bn = cn;
c = z;
cn = zn;
}
MPFR_ASSERTD (bn >= cn);
if (MPFR_LIKELY (bn <= 2))
{
if (bn == 1)
{
/* 1 limb * 1 limb */
umul_ppmm (tmp[1], tmp[0], MPFR_MANT (b)[0], MPFR_MANT (c)[0]);
b1 = tmp[1];
}
else if (MPFR_UNLIKELY (cn == 1))
{
/* 2 limbs * 1 limb */
mp_limb_t t;
umul_ppmm (tmp[1], tmp[0], MPFR_MANT (b)[0], MPFR_MANT (c)[0]);
umul_ppmm (tmp[2], t, MPFR_MANT (b)[1], MPFR_MANT (c)[0]);
add_ssaaaa (tmp[2], tmp[1], tmp[2], tmp[1], 0, t);
b1 = tmp[2];
}
else
{
/* 2 limbs * 2 limbs */
mp_limb_t t1, t2, t3;
/* First 2 limbs * 1 limb */
umul_ppmm (tmp[1], tmp[0], MPFR_MANT (b)[0], MPFR_MANT (c)[0]);
umul_ppmm (tmp[2], t1, MPFR_MANT (b)[1], MPFR_MANT (c)[0]);
add_ssaaaa (tmp[2], tmp[1], tmp[2], tmp[1], 0, t1);
/* Second, the other 2 limbs * 1 limb product */
umul_ppmm (t1, t2, MPFR_MANT (b)[0], MPFR_MANT (c)[1]);
umul_ppmm (tmp[3], t3, MPFR_MANT (b)[1], MPFR_MANT (c)[1]);
add_ssaaaa (tmp[3], t1, tmp[3], t1, 0, t3);
/* Sum those two partial products */
add_ssaaaa (tmp[2], tmp[1], tmp[2], tmp[1], t1, t2);
tmp[3] += (tmp[2] < t1);
b1 = tmp[3];
}
b1 >>= (GMP_NUMB_BITS - 1);
tmp += k - tn;
if (MPFR_UNLIKELY (b1 == 0))
mpn_lshift (tmp, tmp, tn, 1); /* tn <= k, so no stack corruption */
}
else
/* Mulders' mulhigh. Disable if squaring, since it is not tuned for
such a case */
if (MPFR_UNLIKELY (bn > MPFR_MUL_THRESHOLD && b != c))
static void
check_for_zero (void)
{
/* Check that 0 is unsigned! */
mpq_t q;
mpz_t z;
mpfr_t x;
int r;
mpfr_sign_t i;
mpfr_init (x);
mpz_init (z);
mpq_init (q);
mpz_set_ui (z, 0);
mpq_set_ui (q, 0, 1);
MPFR_SET_ZERO (x);
RND_LOOP (r)
{
for (i = MPFR_SIGN_NEG ; i <= MPFR_SIGN_POS ;
i+=MPFR_SIGN_POS-MPFR_SIGN_NEG)
{
MPFR_SET_SIGN(x, i);
mpfr_add_z (x, x, z, (mpfr_rnd_t) r);
if (!MPFR_IS_ZERO(x) || MPFR_SIGN(x)!=i)
{
printf("GMP Zero errors for add_z & rnd=%s & s=%d\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), i);
mpfr_dump (x);
exit (1);
}
mpfr_sub_z (x, x, z, (mpfr_rnd_t) r);
if (!MPFR_IS_ZERO(x) || MPFR_SIGN(x)!=i)
{
printf("GMP Zero errors for sub_z & rnd=%s & s=%d\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), i);
mpfr_dump (x);
exit (1);
}
mpfr_mul_z (x, x, z, (mpfr_rnd_t) r);
if (!MPFR_IS_ZERO(x) || MPFR_SIGN(x)!=i)
{
printf("GMP Zero errors for mul_z & rnd=%s & s=%d\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), i);
mpfr_dump (x);
exit (1);
}
mpfr_add_q (x, x, q, (mpfr_rnd_t) r);
if (!MPFR_IS_ZERO(x) || MPFR_SIGN(x)!=i)
{
printf("GMP Zero errors for add_q & rnd=%s & s=%d\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), i);
mpfr_dump (x);
exit (1);
}
mpfr_sub_q (x, x, q, (mpfr_rnd_t) r);
if (!MPFR_IS_ZERO(x) || MPFR_SIGN(x)!=i)
{
printf("GMP Zero errors for sub_q & rnd=%s & s=%d\n",
mpfr_print_rnd_mode ((mpfr_rnd_t) r), i);
mpfr_dump (x);
exit (1);
}
}
}
mpq_clear (q);
mpz_clear (z);
mpfr_clear (x);
}
/* TODO
* exponents that use more than 16 bytes are not managed
*/
static int
mpfr_fpif_read_exponent_from_file (mpfr_t x, FILE * fh)
{
mpfr_exp_t exponent;
mpfr_uexp_t uexp;
size_t exponent_size;
int sign;
unsigned char buffer[sizeof(mpfr_exp_t)];
if (fh == NULL)
return 1;
if (fread (buffer, 1, 1, fh) != 1)
return 1;
sign = (buffer[0] & 0x80) ? -1 : 1;
exponent = buffer[0] & 0x7F;
exponent_size = 1;
if (exponent > MPFR_EXTERNAL_EXPONENT && exponent < MPFR_KIND_ZERO)
{
mpfr_uexp_t exponent_sign;
exponent_size = exponent - MPFR_EXTERNAL_EXPONENT;
if (exponent_size > sizeof(mpfr_exp_t))
return 1;
if (fread (buffer, exponent_size, 1, fh) != 1)
return 1;
uexp = 0;
getLittleEndianData ((unsigned char *) &uexp, buffer,
sizeof(mpfr_exp_t), exponent_size);
exponent_sign = uexp & ((mpfr_uexp_t) 1 << (8 * exponent_size - 1));
uexp &= ~exponent_sign;
uexp += MPFR_MAX_EMBEDDED_EXPONENT;
exponent = exponent_sign ? - (mpfr_exp_t) uexp : (mpfr_exp_t) uexp;
if (! MPFR_EXP_IN_RANGE (exponent))
return 1;
MPFR_EXP (x) = exponent;
MPFR_SET_SIGN (x, sign);
exponent_size++;
}
else if (exponent == MPFR_KIND_ZERO)
mpfr_set_zero (x, sign);
else if (exponent == MPFR_KIND_INF)
mpfr_set_inf (x, sign);
else if (exponent == MPFR_KIND_NAN)
mpfr_set_nan (x);
else if (exponent < 95)
{
/* FIXME: no sign set. Is this normal? Check with a testcase. */
exponent -= MPFR_MAX_EMBEDDED_EXPONENT;
if (! MPFR_EXP_IN_RANGE (exponent))
return 1;
MPFR_EXP (x) = exponent;
}
else
return 1;
return 0;
}
