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diff --git a/lib/msun/src/e_asinl.c b/lib/msun/src/e_asinl.c
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+
+/* @(#)e_asin.c 1.3 95/01/18 */
+/* FreeBSD: head/lib/msun/src/e_asin.c 176451 2008-02-22 02:30:36Z das */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, 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("$FreeBSD$");
+
+/*
+ * See comments in e_asin.c.
+ * Converted to long double by David Schultz <das@FreeBSD.ORG>.
+ */
+
+#include <float.h>
+
+#include "invtrig.h"
+#include "math.h"
+#include "math_private.h"
+
+static const long double
+one = 1.00000000000000000000e+00,
+huge = 1.000e+300;
+
+long double
+asinl(long double x)
+{
+ union IEEEl2bits u;
+ long double t=0.0,w,p,q,c,r,s;
+ int16_t expsign, expt;
+ u.e = x;
+ expsign = u.xbits.expsign;
+ expt = expsign & 0x7fff;
+ if(expt >= BIAS) { /* |x|>= 1 */
+ if(expt==BIAS && ((u.bits.manh&~LDBL_NBIT)|u.bits.manl)==0)
+ /* asin(1)=+-pi/2 with inexact */
+ return x*pio2_hi+x*pio2_lo;
+ return (x-x)/(x-x); /* asin(|x|>1) is NaN */
+ } else if (expt<BIAS-1) { /* |x|<0.5 */
+ if(expt<ASIN_LINEAR) { /* if |x| is small, asinl(x)=x */
+ if(huge+x>one) return x;/* return x with inexact if x!=0*/
+ } else
+ t = x*x;
+ p = P(t);
+ q = Q(t);
+ w = p/q;
+ return x+x*w;
+ }
+ /* 1> |x|>= 0.5 */
+ w = one-fabsl(x);
+ t = w*0.5;
+ p = P(t);
+ q = Q(t);
+ s = sqrtl(t);
+ if(u.bits.manh>=THRESH) { /* if |x| is close to 1 */
+ w = p/q;
+ t = pio2_hi-(2.0*(s+s*w)-pio2_lo);
+ } else {
+ u.e = s;
+ u.bits.manl = 0;
+ w = u.e;
+ c = (t-w*w)/(s+w);
+ r = p/q;
+ p = 2.0*s*r-(pio2_lo-2.0*c);
+ q = pio4_hi-2.0*w;
+ t = pio4_hi-(p-q);
+ }
+ if(expsign>0) return t; else return -t;
+}
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