1 files changed, 34 insertions, 0 deletions
diff --git a/lib/libm/scalbnf.c b/lib/libm/scalbnf.c
new file mode 100644
index 00000000..38b7d5b3
--- /dev/null
+++ b/lib/libm/scalbnf.c
@@ -0,0 +1,34 @@
+#include <math.h>
+#include <stdint.h>
+
+float scalbnf(float x, int n)
+{
+	union {
+		float f;
+		uint32_t i;
+	} u;
+	float_t y = x;
+
+	if (n > 127) {
+		y *= 0x1p127f;
+		n -= 127;
+		if (n > 127) {
+			y *= 0x1p127f;
+			n -= 127;
+			if (n > 127)
+				n = 127;
+		}
+	} else if (n < -126) {
+		y *= 0x1p-126f * 0x1p24f;
+		n += 126 - 24;
+		if (n < -126) {
+			y *= 0x1p-126f * 0x1p24f;
+			n += 126 - 24;
+			if (n < -126)
+				n = -126;
+		}
+	}
+	u.i = (uint32_t)(0x7f + n) << 23;
+	x = y * u.f;
+	return x;
+}