From 9611c872cafe83a71c8931c990187ea0443c7952 Mon Sep 17 00:00:00 2001 From: vlefevre Date: Wed, 15 Jul 2015 14:17:12 +0000 Subject: [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 --- src/div_2si.c | 3 ++- src/div_2ui.c | 4 +++- 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)); } -- cgit v1.2.1