diff options
Diffstat (limited to 'missing')
-rw-r--r-- | missing/signbit.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/missing/signbit.c b/missing/signbit.c new file mode 100644 index 0000000000..2f7ce8c601 --- /dev/null +++ b/missing/signbit.c @@ -0,0 +1,19 @@ +#include <limits.h> +#include "ruby.h" + +int +signbit(double x) +{ + enum {double_per_long = sizeof(double) / sizeof(long)}; + enum {long_msb = sizeof(long) * CHAR_BIT - 1}; + union {double d; unsigned long i[double_per_long];} u; + unsigned long l; + + u.d = x; +#ifdef WORDS_BIGENDIAN + l = u.i[0]; +#else + l = u.i[double_per_long - 1]; +#endif + return (int)(l >> long_msb); +} |