auto import from //depot/cupcake/@135843
diff --git a/libm/src/s_truncf.c b/libm/src/s_truncf.c
new file mode 100644
index 0000000..86b7247
--- /dev/null
+++ b/libm/src/s_truncf.c
@@ -0,0 +1,53 @@
+/* @(#)s_floor.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#include <sys/cdefs.h>
+/* __FBSDID("$FreeBSD: src/lib/msun/src/s_truncf.c,v 1.1 2004/06/20 09:25:43 das Exp $"); */
+
+/*
+ * truncf(x)
+ * Return x rounded toward 0 to integral value
+ * Method:
+ * Bit twiddling.
+ * Exception:
+ * Inexact flag raised if x not equal to truncf(x).
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+static const float huge = 1.0e30F;
+
+float
+truncf(float x)
+{
+ int32_t i0,j0;
+ u_int32_t i;
+ GET_FLOAT_WORD(i0,x);
+ j0 = ((i0>>23)&0xff)-0x7f;
+ if(j0<23) {
+ if(j0<0) { /* raise inexact if x != 0 */
+ if(huge+x>0.0F) /* |x|<1, so return 0*sign(x) */
+ i0 &= 0x80000000;
+ } else {
+ i = (0x007fffff)>>j0;
+ if((i0&i)==0) return x; /* x is integral */
+ if(huge+x>0.0F) /* raise inexact flag */
+ i0 &= (~i);
+ }
+ } else {
+ if(j0==0x80) return x+x; /* inf or NaN */
+ else return x; /* x is integral */
+ }
+ SET_FLOAT_WORD(x,i0);
+ return x;
+}