From 4abab5ad6c8465a7528ccdd5f49367da05f78bbd Mon Sep 17 00:00:00 2001 From: Vladimir Azarov Date: Tue, 1 Oct 2024 15:47:05 +0200 Subject: Initial version --- src/math/modf.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 src/math/modf.c (limited to 'src/math/modf.c') diff --git a/src/math/modf.c b/src/math/modf.c new file mode 100644 index 0000000..1c8a1db --- /dev/null +++ b/src/math/modf.c @@ -0,0 +1,34 @@ +#include "libm.h" + +double modf(double x, double *iptr) +{ + union {double f; uint64_t i;} u = {x}; + uint64_t mask; + int e = (int)(u.i>>52 & 0x7ff) - 0x3ff; + + /* no fractional part */ + if (e >= 52) { + *iptr = x; + if (e == 0x400 && u.i<<12 != 0) /* nan */ + return x; + u.i &= 1ULL<<63; + return u.f; + } + + /* no integral part*/ + if (e < 0) { + u.i &= 1ULL<<63; + *iptr = u.f; + return x; + } + + mask = -1ULL>>12>>e; + if ((u.i & mask) == 0) { + *iptr = x; + u.i &= 1ULL<<63; + return u.f; + } + u.i &= ~mask; + *iptr = u.f; + return x - u.f; +} -- cgit v1.2.3