aboutsummaryrefslogtreecommitdiff
path: root/lib/mlibc/options/ansi/musl-generic-math/nextafterf.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/nextafterf.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/nextafterf.c30
1 files changed, 30 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/nextafterf.c b/lib/mlibc/options/ansi/musl-generic-math/nextafterf.c
new file mode 100644
index 0000000..75a09f7
--- /dev/null
+++ b/lib/mlibc/options/ansi/musl-generic-math/nextafterf.c
@@ -0,0 +1,30 @@
+#include "libm.h"
+
+float nextafterf(float x, float y)
+{
+ union {float f; uint32_t i;} ux={x}, uy={y};
+ uint32_t ax, ay, e;
+
+ if (isnan(x) || isnan(y))
+ return x + y;
+ if (ux.i == uy.i)
+ return y;
+ ax = ux.i & 0x7fffffff;
+ ay = uy.i & 0x7fffffff;
+ if (ax == 0) {
+ if (ay == 0)
+ return y;
+ ux.i = (uy.i & 0x80000000) | 1;
+ } else if (ax > ay || ((ux.i ^ uy.i) & 0x80000000))
+ ux.i--;
+ else
+ ux.i++;
+ e = ux.i & 0x7f800000;
+ /* raise overflow if ux.f is infinite and x is finite */
+ if (e == 0x7f800000)
+ 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;
+}