auto import from //depot/cupcake/@135843
diff --git a/libm/src/s_tanhf.c b/libm/src/s_tanhf.c
new file mode 100644
index 0000000..0aca6cc
--- /dev/null
+++ b/libm/src/s_tanhf.c
@@ -0,0 +1,56 @@
+/* s_tanhf.c -- float version of s_tanh.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#ifndef lint
+static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_tanhf.c,v 1.8 2005/12/11 11:40:55 bde Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+static const float one=1.0, two=2.0, tiny = 1.0e-30, huge = 1.0e30;
+float
+tanhf(float x)
+{
+ float t,z;
+ int32_t jx,ix;
+
+ GET_FLOAT_WORD(jx,x);
+ ix = jx&0x7fffffff;
+
+ /* x is INF or NaN */
+ if(ix>=0x7f800000) {
+ if (jx>=0) return one/x+one; /* tanh(+-inf)=+-1 */
+ else return one/x-one; /* tanh(NaN) = NaN */
+ }
+
+ /* |x| < 9 */
+ if (ix < 0x41100000) { /* |x|<9 */
+ if (ix<0x39800000) { /* |x|<2**-12 */
+ if(huge+x>one) return x; /* tanh(tiny) = tiny with inexact */
+ }
+ if (ix>=0x3f800000) { /* |x|>=1 */
+ t = expm1f(two*fabsf(x));
+ z = one - two/(t+two);
+ } else {
+ t = expm1f(-two*fabsf(x));
+ z= -t/(t+two);
+ }
+ /* |x| >= 9, return +-1 */
+ } else {
+ z = one - tiny; /* raise inexact flag */
+ }
+ return (jx>=0)? z: -z;
+}