diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-96/s_lroundl.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-96/s_lroundl.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/sysdeps/ieee754/ldbl-96/s_lroundl.c b/sysdeps/ieee754/ldbl-96/s_lroundl.c index e34edd307d..3b43d77e72 100644 --- a/sysdeps/ieee754/ldbl-96/s_lroundl.c +++ b/sysdeps/ieee754/ldbl-96/s_lroundl.c @@ -1,5 +1,5 @@ /* Round long double value to long int. - Copyright (C) 1997-2015 Free Software Foundation, Inc. + Copyright (C) 1997-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -17,6 +17,8 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ +#include <fenv.h> +#include <limits.h> #include <math.h> #include <math_private.h> @@ -49,6 +51,13 @@ __lroundl (long double x) } result = j >> (31 - j0); +#ifdef FE_INVALID + if (sizeof (long int) == 4 + && sign == 1 + && result == LONG_MIN) + /* Rounding brought the value out of range. */ + feraiseexcept (FE_INVALID); +#endif } } else if (j0 < (int32_t) (8 * sizeof (long int)) - 1) @@ -58,19 +67,41 @@ __lroundl (long double x) else { u_int32_t j = i1 + (0x80000000 >> (j0 - 31)); + unsigned long int ures = i0; + if (j < i1) - ++i0; + ++ures; if (j0 == 31) - result = (long int) i0; + result = ures; else - result = ((long int) i0 << (j0 - 31)) | (j >> (63 - j0)); + { + result = (ures << (j0 - 31)) | (j >> (63 - j0)); +#ifdef FE_INVALID + if (sizeof (long int) == 8 + && sign == 1 + && result == LONG_MIN) + /* Rounding brought the value out of range. */ + feraiseexcept (FE_INVALID); +#endif + } } } else { - /* The number is too large. It is left implementation defined - what happens. */ + /* The number is too large. Unless it rounds to LONG_MIN, + FE_INVALID must be raised and the return value is + unspecified. */ +#ifdef FE_INVALID + if (sizeof (long int) == 4 + && x <= (long double) LONG_MIN - 0.5L) + { + /* If truncation produces LONG_MIN, the cast will not raise + the exception, but may raise "inexact". */ + feraiseexcept (FE_INVALID); + return LONG_MIN; + } +#endif return (long int) x; } |