diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_lrint.c')
-rw-r--r-- | sysdeps/ieee754/dbl-64/s_lrint.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_lrint.c b/sysdeps/ieee754/dbl-64/s_lrint.c index 353d5f503b..39f95adc21 100644 --- a/sysdeps/ieee754/dbl-64/s_lrint.c +++ b/sysdeps/ieee754/dbl-64/s_lrint.c @@ -18,6 +18,8 @@ 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> @@ -62,8 +64,22 @@ __lrint (double x) result = ((long int) i0 << (j0 - 20)) | (i1 << (j0 - 52)); else { - w = math_narrow_eval (two52[sx] + x); - t = w - two52[sx]; +#if defined FE_INVALID || defined FE_INEXACT + /* X < LONG_MAX + 1 implied by J0 < 31. */ + if (sizeof (long int) == 4 + && x > (double) LONG_MAX) + { + /* In the event of overflow we must raise the "invalid" + exception, but not "inexact". */ + t = __nearbyint (x); + feraiseexcept (t == LONG_MAX ? FE_INEXACT : FE_INVALID); + } + else +#endif + { + w = math_narrow_eval (two52[sx] + x); + t = w - two52[sx]; + } EXTRACT_WORDS (i0, i1, t); j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; i0 &= 0xfffff; @@ -77,8 +93,21 @@ __lrint (double x) } 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. */ +#if defined FE_INVALID || defined FE_INEXACT + if (sizeof (long int) == 4 + && x < (double) LONG_MIN + && x > (double) LONG_MIN - 1.0) + { + /* If truncation produces LONG_MIN, the cast will not raise + the exception, but may raise "inexact". */ + t = __nearbyint (x); + feraiseexcept (t == LONG_MIN ? FE_INEXACT : FE_INVALID); + return LONG_MIN; + } +#endif return (long int) x; } |