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diff --git a/src/math/e_sinh.c b/src/math/e_sinh.c
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+
+/* @(#)e_sinh.c 1.3 95/01/18 */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* sinh(x)
+ * Method : 
+ * mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2
+ *      1. Replace x by |x| (sinh(-x) = -sinh(x)). 
+ *      2. 
+ *                                                  E + E/(E+1)
+ *          0        <= x <= 22     :  sinh(x) := --------------, E=expm1(x)
+ *                                                      2
+ *
+ *          22       <= x <= lnovft :  sinh(x) := exp(x)/2 
+ *          lnovft   <= x <= ln2ovft:  sinh(x) := exp(x/2)/2 * exp(x/2)
+ *          ln2ovft  <  x           :  sinh(x) := x*shuge (overflow)
+ *
+ * Special cases:
+ *      sinh(x) is |x| if x is +INF, -INF, or NaN.
+ *      only sinh(0)=0 is exact for finite x.
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+static const double one = 1.0, shuge = 1.0e307;
+
+double
+sinh(double x)
+{
+        double t,w,h;
+        int32_t ix,jx;
+        uint32_t lx;
+
+    /* High word of |x|. */
+        GET_HIGH_WORD(jx,x);
+        ix = jx&0x7fffffff;
+
+    /* x is INF or NaN */
+        if(ix>=0x7ff00000) return x+x;  
+
+        h = 0.5;
+        if (jx<0) h = -h;
+    /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */
+        if (ix < 0x40360000) {          /* |x|<22 */
+            if (ix<0x3e300000)          /* |x|<2**-28 */
+                if(shuge+x>one) return x;/* sinh(tiny) = tiny with inexact */
+            t = expm1(fabs(x));
+            if(ix<0x3ff00000) return h*(2.0*t-t*t/(t+one));
+            return h*(t+t/(t+one));
+        }
+
+    /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
+        if (ix < 0x40862E42)  return h*exp(fabs(x));
+
+    /* |x| in [log(maxdouble), overflowthresold] */
+        GET_LOW_WORD(lx,x);
+        if (ix<0x408633CE || ((ix==0x408633ce)&&(lx<=(uint32_t)0x8fb9f87d))) {
+            w = exp(0.5*fabs(x));
+            t = h*w;
+            return t*w;
+        }
+
+    /* |x| > overflowthresold, sinh(x) overflow */
+        return x*shuge;
+}