Imported gcc-4.4.3

[msp430-gcc.git] / mpfr / sech.c

diff --git a/mpfr/sech.c b/mpfr/sech.c
new file mode 100644 (file)
index 0000000..d1b7039
--- /dev/null
+++ b/mpfr/sech.c
@@ -0,0 +1,40 @@
+/* mpfr_sech - Hyperbolic secant function = 1/cosh.
+
+Copyright 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Contributed by the Arenaire and Cacao projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or (at your
+option) any later version.
+
+The GNU MPFR Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MPFR Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+/* The hyperbolic secant function is defined by sech(x)=1/cosh(x):
+    csc (NaN) = NaN.
+    csc (+Inf) = csc (-Inf) = 0+.
+    csc (+0) = csc (-0) = 1.
+ */
+
+#define FUNCTION mpfr_sech
+#define INVERSE  mpfr_cosh
+#define ACTION_NAN(y) do { MPFR_SET_NAN(y); MPFR_RET_NAN; } while (1)
+#define ACTION_INF(y) return mpfr_set_ui (y, 0, GMP_RNDN)
+#define ACTION_ZERO(y,x) return mpfr_set_ui (y, 1, rnd_mode)
+/* for x near 0, sech(x) = 1 - x^2/2 + ..., more precisely |sech(x)-1| <= x^2/2
+   for |x| <= 1. The tiny action is the same as for cos(x). */
+#define ACTION_TINY(y,x,r) \
+  MPFR_FAST_COMPUTE_IF_SMALL_INPUT(y, __gmpfr_one, -2 * MPFR_GET_EXP (x), 1, \
+                                   0, r, inexact = _inexact; goto end)
+
+#include "gen_inverse.h"