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authorAndreas Jaeger <aj@suse.de>2001-06-04 08:31:38 +0000
committerAndreas Jaeger <aj@suse.de>2001-06-04 08:31:38 +0000
commit94a38ea3c432919dc1289957025f6fc5b2e3d7a7 (patch)
tree9f80bf6bc1d43497bf2acd4631f2c9655354351e /sysdeps/ieee754
parenteaeeb1eb428500658671f12aa4938543396ab7b9 (diff)
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128 bit sinh implementation.
Diffstat (limited to 'sysdeps/ieee754')
-rw-r--r--sysdeps/ieee754/ldbl-128/e_sinhl.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/e_sinhl.c b/sysdeps/ieee754/ldbl-128/e_sinhl.c
new file mode 100644
index 0000000000..71e283d2de
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/e_sinhl.c
@@ -0,0 +1,105 @@
+/* e_sinhl.c -- long double version of e_sinh.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@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.
+ * ====================================================
+ */
+
+/* Changes for 128-bit long double contributed by
+ Stephen L. Moshier <moshier@na-net.ornl.gov> */
+
+/* __ieee754_sinhl(x)
+ * Method :
+ * mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2
+ * 1. Replace x by |x| (sinhl(-x) = -sinhl(x)).
+ * 2.
+ * E + E/(E+1)
+ * 0 <= x <= 25 : sinhl(x) := --------------, E=expm1l(x)
+ * 2
+ *
+ * 25 <= x <= lnovft : sinhl(x) := expl(x)/2
+ * lnovft <= x <= ln2ovft: sinhl(x) := expl(x/2)/2 * expl(x/2)
+ * ln2ovft < x : sinhl(x) := x*shuge (overflow)
+ *
+ * Special cases:
+ * sinhl(x) is |x| if x is +INF, -INF, or NaN.
+ * only sinhl(0)=0 is exact for finite x.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double one = 1.0, shuge = 1.0e4931L,
+ovf_thresh = 1.1357216553474703894801348310092223067821E4L;
+#else
+static long double one = 1.0, shuge = 1.0e4931L,
+ovf_thresh = 1.1357216553474703894801348310092223067821E4L;
+#endif
+
+#ifdef __STDC__
+long double
+__ieee754_sinhl (long double x)
+#else
+long double
+__ieee754_sinhl (x)
+ long double x;
+#endif
+{
+ long double t, w, h;
+ u_int32_t jx, ix;
+ ieee854_long_double_shape_type u;
+
+ /* Words of |x|. */
+ u.value = x;
+ jx = u.parts32.w0;
+ ix = jx & 0x7fffffff;
+
+ /* x is INF or NaN */
+ if (ix >= 0x7fff0000)
+ return x + x;
+
+ h = 0.5;
+ if (jx & 0x80000000)
+ h = -h;
+
+ /* Absolute value of x. */
+ u.parts32.w0 = ix;
+
+ /* |x| in [0,40], return sign(x)*0.5*(E+E/(E+1))) */
+ if (ix <= 0x40044000)
+ {
+ if (ix < 0x3fc60000) /* |x| < 2^-57 */
+ if (shuge + x > one)
+ return x; /* sinh(tiny) = tiny with inexact */
+ t = __expm1l (u.value);
+ if (ix < 0x3fff0000)
+ return h * (2.0 * t - t * t / (t + one));
+ return h * (t + t / (t + one));
+ }
+
+ /* |x| in [40, log(maxdouble)] return 0.5*exp(|x|) */
+ if (ix <= 0x400c62e3) /* 11356.375 */
+ return h * __ieee754_expl (u.value);
+
+ /* |x| in [log(maxdouble), overflowthreshold]
+ Overflow threshold is log(2 * maxdouble). */
+ if (u.value <= ovf_thresh)
+ {
+ w = __ieee754_expl (0.5 * u.value);
+ t = h * w;
+ return t * w;
+ }
+
+ /* |x| > overflowthreshold, sinhl(x) overflow */
+ return x * shuge;
+}