From 30634165980deaeead9f4e71e0ff6a5c9d897776 Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Mon, 14 Jul 2025 22:39:34 -0400 Subject: usr: libc: Add math.h + musl math impl port Signed-off-by: Ian Moffett --- lib/libc/src/musl-math/nextafter.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 lib/libc/src/musl-math/nextafter.c (limited to 'lib/libc/src/musl-math/nextafter.c') diff --git a/lib/libc/src/musl-math/nextafter.c b/lib/libc/src/musl-math/nextafter.c new file mode 100644 index 0000000..ab5795a --- /dev/null +++ b/lib/libc/src/musl-math/nextafter.c @@ -0,0 +1,31 @@ +#include "libm.h" + +double nextafter(double x, double y) +{ + union {double f; uint64_t i;} ux={x}, uy={y}; + uint64_t ax, ay; + int e; + + if (isnan(x) || isnan(y)) + return x + y; + if (ux.i == uy.i) + return y; + ax = ux.i & -1ULL/2; + ay = uy.i & -1ULL/2; + if (ax == 0) { + if (ay == 0) + return y; + ux.i = (uy.i & 1ULL<<63) | 1; + } else if (ax > ay || ((ux.i ^ uy.i) & 1ULL<<63)) + ux.i--; + else + ux.i++; + e = ux.i >> 52 & 0x7ff; + /* raise overflow if ux.f is infinite and x is finite */ + if (e == 0x7ff) + FORCE_EVAL(x+x); + /* raise underflow if ux.f is subnormal or zero */ + if (e == 0) + FORCE_EVAL(x*x + ux.f*ux.f); + return ux.f; +} -- cgit v1.2.3