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-rw-r--r--src/math/sinhf.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/src/math/sinhf.c b/src/math/sinhf.c
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--- /dev/null
+++ b/src/math/sinhf.c
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+/* origin: FreeBSD /usr/src/lib/msun/src/e_sinhf.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.
+ * ====================================================
+ */
+
+#include "libm.h"
+
+static const float one = 1.0, huge = 1.0e37;
+
+float sinhf(float x)
+{
+	float t, h;
+	int32_t ix, jx;
+
+	GET_FLOAT_WORD(jx, x);
+	ix = jx & 0x7fffffff;
+
+	/* x is INF or NaN */
+	if (ix >= 0x7f800000)
+		return x + x;
+
+	h = 0.5;
+	if (jx < 0)
+		h = -h;
+	/* |x| in [0,9], return sign(x)*0.5*(E+E/(E+1))) */
+	if (ix < 0x41100000) {   /* |x|<9 */
+		if (ix < 0x39800000)  /* |x|<2**-12 */
+			/* raise inexact, return x */
+			if (huge+x > one)
+				return x;
+		t = expm1f(fabsf(x));
+		if (ix < 0x3f800000)
+			return h*((float)2.0*t - t*t/(t+one));
+		return h*(t + t/(t+one));
+	}
+
+	/* |x| in [9, logf(maxfloat)] return 0.5*exp(|x|) */
+	if (ix < 0x42b17217)
+		return h*expf(fabsf(x));
+
+	/* |x| in [logf(maxfloat), overflowthresold] */
+	if (ix <= 0x42b2d4fc)
+		return h * 2.0f * __expo2f(fabsf(x)); /* h is for sign only */
+
+	/* |x| > overflowthresold, sinh(x) overflow */
+	return x*huge;
+}