diff --git a/libm/i387/s_copysignl.S b/libm/i387/s_copysignl.S
new file mode 100644
index 0000000..4c3a374
--- /dev/null
+++ b/libm/i387/s_copysignl.S
@@ -0,0 +1,17 @@
+/*
+ * Based on code written by J.T. Conklin <jtc@NetBSD.org>.
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+__FBSDID("$FreeBSD: src/lib/msun/i387/s_copysignl.S,v 1.1 2005/04/16 21:12:55 das Exp $")
+
+ENTRY(copysignl)
+	movl	24(%esp),%edx
+	andl	$0x8000,%edx
+	movl	12(%esp),%eax
+	andl	$0x7fff,%eax
+	orl	%edx,%eax
+	movl	%eax,12(%esp)
+	fldt	4(%esp)
+	ret