diff options
Diffstat (limited to 'winsup/mingw/mingwex/math/llround.c')
| -rw-r--r-- | winsup/mingw/mingwex/math/llround.c | 35 |
1 files changed, 15 insertions, 20 deletions
diff --git a/winsup/mingw/mingwex/math/llround.c b/winsup/mingw/mingwex/math/llround.c index f8fafc48d..45b754c75 100644 --- a/winsup/mingw/mingwex/math/llround.c +++ b/winsup/mingw/mingwex/math/llround.c @@ -1,24 +1,19 @@ -#include <fenv.h> #include <math.h> +#include <limits.h> +#include <errno.h> long long -llround (double x) { - long long retval; - unsigned short saved_cw, _cw; - __asm__ ( - "fnstcw %0;" : "=m" (saved_cw) - ); /* save control word */ - _cw = ~(FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | FE_TOWARDZERO) - | (x > 0.0 ? FE_UPWARD : FE_DOWNWARD); /* round away from zero */ - __asm__ ( - "fldcw %0;" : : "m" (_cw) - ); /* load the rounding control */ - __asm__ __volatile__ ( - "fistpll %0" : "=m" (retval) : "t" (x) : "st" - ); - __asm__ ( - "fldcw %0;" : : "m" (saved_cw) - ); /* restore control word */ - return retval; +llround (double x) +{ + /* Add +/- 0.5, then round towards zero. */ + double tmp = trunc (x + (x >= 0.0 ? 0.5 : -0.5)); + if (!isfinite (tmp) + || tmp > (double)LONG_LONG_MAX + || tmp < (double)LONG_LONG_MIN) + { + errno = ERANGE; + /* Undefined behaviour, so we could return anything. */ + /* return tmp > 0.0 ? LONG_LONG_MAX : LONG_LONG_MIN; */ + } + return (long long)tmp; } - |