diff options
author | Nicholas Noll <nbnoll@eml.cc> | 2021-12-05 16:16:21 -0800 |
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committer | Nicholas Noll <nbnoll@eml.cc> | 2021-12-05 16:16:21 -0800 |
commit | 07e77936d535e58b0aeb4f2a11400c1050556739 (patch) | |
tree | fb50fad6436ecbc159505bee73a92cd289b99a07 /src/base/math/copysign.c | |
parent | b48327d357e0818d1a6ae2a064cfa7d1567e1242 (diff) |
Feat: added math library
Used Plan9's libc as starting point. This cleans up dangling references
due to loss of libc.
Diffstat (limited to 'src/base/math/copysign.c')
-rw-r--r-- | src/base/math/copysign.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/src/base/math/copysign.c b/src/base/math/copysign.c new file mode 100644 index 0000000..0e7540b --- /dev/null +++ b/src/base/math/copysign.c @@ -0,0 +1,12 @@ +#include <u.h> +#include <base.h> + +double +math·copysign(double x, double y) +{ + union {double f; uint64 i;} ux={x}, uy={y}; + ux.i &= -1ULL/2; + ux.i |= uy.i & 1ULL<<63; + + return ux.f; +} |