1 files changed, 10 insertions, 0 deletions
diff --git a/lib/libm/logbf.c b/lib/libm/logbf.c
new file mode 100644
index 00000000..2344ed3a
--- /dev/null
+++ b/lib/libm/logbf.c
@@ -0,0 +1,10 @@
+#include <math.h>
+
+float logbf(float x)
+{
+	if (!isfinite(x))
+		return x * x;
+	if (x == 0)
+		return -1 / (x * x);
+	return ilogbf(x);
+}