auto import from //depot/cupcake/@135843
diff --git a/libm/src/s_cbrtf.c b/libm/src/s_cbrtf.c
new file mode 100644
index 0000000..75569a2
--- /dev/null
+++ b/libm/src/s_cbrtf.c
@@ -0,0 +1,79 @@
+/* s_cbrtf.c -- float version of s_cbrt.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ * Debugged and optimized by Bruce D. Evans.
+ */
+
+/*
+ * ====================================================
+ * 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_cbrtf.c,v 1.12 2005/12/13 20:17:23 bde Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+/* cbrtf(x)
+ * Return cube root of x
+ */
+static const unsigned
+ B1 = 709958130, /* B1 = (127-127.0/3-0.03306235651)*2**23 */
+ B2 = 642849266; /* B2 = (127-127.0/3-24/3-0.03306235651)*2**23 */
+
+static const float
+C = 5.4285717010e-01, /* 19/35 = 0x3f0af8b0 */
+D = -7.0530611277e-01, /* -864/1225 = 0xbf348ef1 */
+E = 1.4142856598e+00, /* 99/70 = 0x3fb50750 */
+F = 1.6071428061e+00, /* 45/28 = 0x3fcdb6db */
+G = 3.5714286566e-01; /* 5/14 = 0x3eb6db6e */
+
+float
+cbrtf(float x)
+{
+ float r,s,t,w;
+ int32_t hx;
+ u_int32_t sign;
+ u_int32_t high;
+
+ GET_FLOAT_WORD(hx,x);
+ sign=hx&0x80000000; /* sign= sign(x) */
+ hx ^=sign;
+ if(hx>=0x7f800000) return(x+x); /* cbrt(NaN,INF) is itself */
+ if(hx==0)
+ return(x); /* cbrt(0) is itself */
+
+ /* rough cbrt to 5 bits */
+ if(hx<0x00800000) { /* subnormal number */
+ SET_FLOAT_WORD(t,0x4b800000); /* set t= 2**24 */
+ t*=x;
+ GET_FLOAT_WORD(high,t);
+ SET_FLOAT_WORD(t,sign|((high&0x7fffffff)/3+B2));
+ } else
+ SET_FLOAT_WORD(t,sign|(hx/3+B1));
+
+ /* new cbrt to 23 bits */
+ r=t*t/x;
+ s=C+r*t;
+ t*=G+F/(s+E+D/s);
+
+ /* chop t to 12 bits and make it larger in magnitude than cbrt(x) */
+ GET_FLOAT_WORD(high,t);
+ SET_FLOAT_WORD(t,(high&0xfffff000)+0x00001000);
+
+ /* one step Newton iteration to 24 bits with error less than 0.667 ulps */
+ s=t*t; /* t*t is exact */
+ r=x/s;
+ w=t+t;
+ r=(r-t)/(w+r); /* r-t is exact */
+ t=t+t*r;
+
+ return(t);
+}