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-rw-r--r--mpfr/mul_ui.c85
1 files changed, 44 insertions, 41 deletions
diff --git a/mpfr/mul_ui.c b/mpfr/mul_ui.c
index 8c916273d..72f9decef 100644
--- a/mpfr/mul_ui.c
+++ b/mpfr/mul_ui.c
@@ -1,6 +1,6 @@
/* mpfr_mul_ui -- multiply a floating-point number by a machine integer
-Copyright (C) 1999, 2001, 2002 Free Software Foundation, Inc.
+Copyright (C) 1999-2002 Free Software Foundation, Inc.
This file is part of the MPFR Library.
@@ -19,7 +19,6 @@ along with the MPFR Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
-#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
@@ -29,90 +28,94 @@ MA 02111-1307, USA. */
int
mpfr_mul_ui (mpfr_ptr y, mpfr_srcptr x, unsigned long int u, mp_rnd_t rnd_mode)
{
- mp_limb_t *my, *old_my;
- unsigned long xn, yn, cnt, c;
- int inexact;
+ mp_limb_t *yp, *old_yp;
+ mp_size_t xn, yn;
+ int cnt, c, inexact;
TMP_DECL(marker);
if (MPFR_IS_NAN(x))
{
- MPFR_CLEAR_FLAGS(y);
MPFR_SET_NAN(y);
- return 1; /* a NaN is always inexact */
+ MPFR_RET_NAN;
}
if (MPFR_IS_INF(x))
{
- MPFR_CLEAR_FLAGS(y);
- if (u)
- {
- MPFR_SET_INF(y);
- if (MPFR_SIGN(y) != MPFR_SIGN(x))
- MPFR_CHANGE_SIGN(y);
- return 0; /* infinity is exact */
+ if (u != 0)
+ {
+ MPFR_CLEAR_FLAGS(y);
+ MPFR_SET_INF(y);
+ MPFR_SET_SAME_SIGN(y, x);
+ MPFR_RET(0); /* infinity is exact */
}
else /* 0 * infinity */
{
MPFR_SET_NAN(y);
- return 1; /* NaN is inexact */
+ MPFR_RET_NAN;
}
}
- if (MPFR_IS_ZERO(x) || !u)
+ MPFR_CLEAR_FLAGS(y);
+
+ if (u == 0 || MPFR_IS_ZERO(x))
{
- MPFR_CLEAR_FLAGS(y);
MPFR_SET_ZERO(y);
- return 0; /* zero is exact */
+ MPFR_SET_SAME_SIGN(y, x);
+ MPFR_RET(0); /* zero is exact */
}
- MPFR_CLEAR_FLAGS(y);
-
if (u == 1)
return mpfr_set (y, x, rnd_mode);
TMP_MARK(marker);
- my = MPFR_MANT(y);
+ yp = MPFR_MANT(y);
yn = (MPFR_PREC(y) - 1) / BITS_PER_MP_LIMB + 1;
xn = (MPFR_PREC(x) - 1) / BITS_PER_MP_LIMB + 1;
- old_my = my;
+ old_yp = yp;
+ MPFR_ASSERTN(xn < MP_SIZE_T_MAX);
if (yn < xn + 1)
- my = (mp_ptr) TMP_ALLOC ((xn + 1) * BYTES_PER_MP_LIMB);
+ yp = (mp_ptr) TMP_ALLOC ((size_t) (xn + 1) * BYTES_PER_MP_LIMB);
+
+ yp[xn] = mpn_mul_1 (yp, MPFR_MANT(x), xn, u);
- my[xn] = mpn_mul_1 (my, MPFR_MANT(x), xn, u);
-
- /* x * u is stored in my[xn], ..., my[0] */
+ /* x * u is stored in yp[xn], ..., yp[0] */
/* since the case u=1 was treated above, we have u >= 2, thus
- my[xn] >= 1 since x was msb-normalized */
- MPFR_ASSERTN(my[xn] != 0);
- cnt = 0;
- if ((my[xn] & MP_LIMB_T_HIGHBIT) == 0)
+ yp[xn] >= 1 since x was msb-normalized */
+ MPFR_ASSERTN(yp[xn] != 0);
+ if ((yp[xn] & MP_LIMB_T_HIGHBIT) == 0)
{
- count_leading_zeros(cnt, my[xn]);
- mpn_lshift (my, my, xn + 1, cnt);
+ count_leading_zeros(cnt, yp[xn]);
+ mpn_lshift (yp, yp, xn + 1, cnt);
+ }
+ else
+ {
+ cnt = 0;
}
- /* now my[xn], ..., my[0] is msb-normalized too, and has at most
+ /* now yp[xn], ..., yp[0] is msb-normalized too, and has at most
PREC(x) + (BITS_PER_MP_LIMB - cnt) non-zero bits */
- c = mpfr_round_raw (old_my, my, (xn + 1) * BITS_PER_MP_LIMB,
+ c = mpfr_round_raw (old_yp, yp, (mp_prec_t) (xn + 1) * BITS_PER_MP_LIMB,
(MPFR_SIGN(x) < 0), MPFR_PREC(y), rnd_mode, &inexact);
- MPFR_EXP(y) = MPFR_EXP(x) + BITS_PER_MP_LIMB - cnt;
+ cnt = BITS_PER_MP_LIMB - cnt;
if (c) /* rounded result is 1.0000000000000000... */
{
- old_my[yn-1] = MP_LIMB_T_HIGHBIT;
- MPFR_EXP(y) ++;
+ old_yp[yn-1] = MP_LIMB_T_HIGHBIT;
+ cnt++;
}
- /* set sign */
- if (MPFR_SIGN(y) * MPFR_SIGN(x) < 0)
- MPFR_CHANGE_SIGN(y);
-
TMP_FREE(marker);
+ if (__mpfr_emax < MPFR_EMAX_MIN + cnt || MPFR_EXP(x) > __mpfr_emax - cnt)
+ return mpfr_set_overflow(y, rnd_mode, MPFR_SIGN(x));
+
+ MPFR_EXP(y) = MPFR_EXP(x) + cnt;
+ MPFR_SET_SAME_SIGN(y, x);
+
return inexact;
}