diff options
| author | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2015-07-15 14:17:12 +0000 |
|---|---|---|
| committer | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2015-07-15 14:17:12 +0000 |
| commit | 9611c872cafe83a71c8931c990187ea0443c7952 (patch) | |
| tree | 87c903de576b6d04b3a70e2d64828d04e4e59ea7 | |
| parent | 1e88edcf7cb78cc454a39e6d1f2b204c218b5b04 (diff) | |
| download | mpfr-9611c872cafe83a71c8931c990187ea0443c7952.tar.gz | |
[src/{div_2si.c,div_2ui.c,mul_2si.c}] Fixed some underflow cases in
rounding to nearest when the exact result is -2^(emin-2), i.e. the
middle of 0 and the minimum negative number in absolute value.
git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@9616 280ebfd0-de03-0410-8827-d642c229c3f4
| -rw-r--r-- | src/div_2si.c | 3 | ||||
| -rw-r--r-- | src/div_2ui.c | 4 | ||||
| -rw-r--r-- | src/mul_2si.c | 3 |
3 files changed, 7 insertions, 3 deletions
diff --git a/src/div_2si.c b/src/div_2si.c index 4220bcfae..140713f92 100644 --- a/src/div_2si.c +++ b/src/div_2si.c @@ -45,7 +45,8 @@ mpfr_div_2si (mpfr_ptr y, mpfr_srcptr x, long int n, mpfr_rnd_t rnd_mode) if (rnd_mode == MPFR_RNDN && (__gmpfr_emin > MPFR_EMAX_MAX - (n - 1) || exp < __gmpfr_emin + (n - 1) || - (inexact >= 0 && mpfr_powerof2_raw (y)))) + ((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)); } diff --git a/src/div_2ui.c b/src/div_2ui.c index 3aa8b6ae8..e548744d0 100644 --- a/src/div_2ui.c +++ b/src/div_2ui.c @@ -44,7 +44,9 @@ mpfr_div_2ui (mpfr_ptr y, mpfr_srcptr x, unsigned long n, mpfr_rnd_t rnd_mode) if (MPFR_UNLIKELY (n >= diffexp)) /* exp - n <= emin - 1 */ { if (rnd_mode == MPFR_RNDN && - (n > diffexp || (inexact >= 0 && mpfr_powerof2_raw (y)))) + (n > diffexp || + ((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)); } diff --git a/src/mul_2si.c b/src/mul_2si.c index 0b02e2940..bc5e47934 100644 --- a/src/mul_2si.c +++ b/src/mul_2si.c @@ -48,7 +48,8 @@ mpfr_mul_2si (mpfr_ptr y, mpfr_srcptr x, long int n, mpfr_rnd_t rnd_mode) if (rnd_mode == MPFR_RNDN && (__gmpfr_emin > MPFR_EMAX_MAX + (n + 1) || exp < __gmpfr_emin - (n + 1) || - (inexact >= 0 && mpfr_powerof2_raw (y)))) + ((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)); } |