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author | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
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committer | Taru Karttunen <taruti@taruti.net> | 2011-03-30 15:46:40 +0300 |
commit | e5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch) | |
tree | d8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/ape/lib/fmt/nan64.c |
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/ape/lib/fmt/nan64.c')
-rwxr-xr-x | sys/src/ape/lib/fmt/nan64.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/sys/src/ape/lib/fmt/nan64.c b/sys/src/ape/lib/fmt/nan64.c new file mode 100755 index 000000000..a02a3adb6 --- /dev/null +++ b/sys/src/ape/lib/fmt/nan64.c @@ -0,0 +1,76 @@ +/* + * 64-bit IEEE not-a-number routines. + * This is big/little-endian portable assuming that + * the 64-bit doubles and 64-bit integers have the + * same byte ordering. + */ + +#include "nan.h" + +#ifdef __APPLE__ +#define _NEEDLL +#endif + +typedef unsigned long long uvlong; +typedef unsigned long ulong; + +#ifdef _NEEDLL +static uvlong uvnan = 0x7FF0000000000001LL; +static uvlong uvinf = 0x7FF0000000000000LL; +static uvlong uvneginf = 0xFFF0000000000000LL; +#else +static uvlong uvnan = 0x7FF0000000000001; +static uvlong uvinf = 0x7FF0000000000000; +static uvlong uvneginf = 0xFFF0000000000000; +#endif + +double +__NaN(void) +{ + uvlong *p; + + /* gcc complains about "return *(double*)&uvnan;" */ + p = &uvnan; + return *(double*)p; +} + +int +__isNaN(double d) +{ + uvlong x; + double *p; + + p = &d; + x = *(uvlong*)p; + return (ulong)(x>>32)==0x7FF00000 && !__isInf(d, 0); +} + +double +__Inf(int sign) +{ + uvlong *p; + + if(sign < 0) + p = &uvinf; + else + p = &uvneginf; + return *(double*)p; +} + +int +__isInf(double d, int sign) +{ + uvlong x; + double *p; + + p = &d; + x = *(uvlong*)p; + if(sign == 0) + return x==uvinf || x==uvneginf; + else if(sign > 0) + return x==uvinf; + else + return x==uvneginf; +} + + |