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authorIan Moffett <ian@osmora.org>2025-07-14 22:39:34 -0400
committerIan Moffett <ian@osmora.org>2025-07-14 23:27:58 -0400
commit30634165980deaeead9f4e71e0ff6a5c9d897776 (patch)
tree18546a9d493a699eb3ea23ab5cc792d40cf82d7d /lib/libc/src/musl-math/roundl.c
parent83acdbef7ae961c2ae296835df3f368573c89eeb (diff)
usr: libc: Add math.h + musl math impl portexpt
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'lib/libc/src/musl-math/roundl.c')
-rw-r--r--lib/libc/src/musl-math/roundl.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/libc/src/musl-math/roundl.c b/lib/libc/src/musl-math/roundl.c
new file mode 100644
index 0000000..f4ff682
--- /dev/null
+++ b/lib/libc/src/musl-math/roundl.c
@@ -0,0 +1,37 @@
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+long double roundl(long double x)
+{
+ return round(x);
+}
+#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
+
+static const long double toint = 1/LDBL_EPSILON;
+
+long double roundl(long double x)
+{
+ union ldshape u = {x};
+ int e = u.i.se & 0x7fff;
+ long double y;
+
+ if (e >= 0x3fff+LDBL_MANT_DIG-1)
+ return x;
+ if (u.i.se >> 15)
+ x = -x;
+ if (e < 0x3fff-1) {
+ FORCE_EVAL(x + toint);
+ return 0*u.f;
+ }
+ y = x + toint - toint - x;
+ if (y > 0.5)
+ y = y + x - 1;
+ else if (y <= -0.5)
+ y = y + x + 1;
+ else
+ y = y + x;
+ if (u.i.se >> 15)
+ y = -y;
+ return y;
+}
+#endif