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authorRoland McGrath <roland@gnu.org>1996-03-05 21:41:30 +0000
committerRoland McGrath <roland@gnu.org>1996-03-05 21:41:30 +0000
commitf7eac6eb504f4baf13dbb4d26717942df050ebe6 (patch)
tree95ff129c06c7f6f246a5e2bfa489ba6382659d19 /sysdeps/libm-ieee754/s_asinh.c
parent1521668f2afae1dc2ef5d7ffaeb84353b36874dd (diff)
Mon Mar 4 20:54:40 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
* Makeconfig ($(common-objpfx)config.make): Depend on config.h.in. Mon Mar 4 17:35:09 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> * hurd/catch-signal.c (hurd_safe_memmove): New function. (hurd_safe_copyin, hurd_safe_copyout): New functions. * hurd/hurd/sigpreempt.h: Declare them. Sun Mar 3 08:43:44 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu> Replace math code with fdlibm from Sun as modified for netbsd by JT Conklin and Ian Taylor, including x86 FPU support. * sysdeps/libm-ieee754, sysdeps/libm-i387: New directories. * math/math_private.h: New file. * sysdeps/i386/fpu/Implies: New file. * sysdeps/ieee754/Implies: New file. * math/machine/asm.h, math/machine/endian.h: New files. * math/Makefile, math/math.h: Rewritten. * mathcalls.h, math/mathcalls.h: New file, broken out of math.h. * math/finite.c: File removed. * sysdeps/generic/Makefile [$(subdir)=math]: Frobnication removed. * math/test-math.c: Include errno.h and string.h. * sysdeps/unix/bsd/dirstream.h: File removed. * sysdeps/unix/bsd/readdir.c: File removed.
Diffstat (limited to 'sysdeps/libm-ieee754/s_asinh.c')
-rw-r--r--sysdeps/libm-ieee754/s_asinh.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_asinh.c b/sysdeps/libm-ieee754/s_asinh.c
new file mode 100644
index 0000000000..bb3c495dfc
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_asinh.c
@@ -0,0 +1,70 @@
+/* @(#)s_asinh.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: s_asinh.c,v 1.9 1995/05/12 04:57:37 jtc Exp $";
+#endif
+
+/* asinh(x)
+ * Method :
+ * Based
+ * asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
+ * we have
+ * asinh(x) := x if 1+x*x=1,
+ * := sign(x)*(log(x)+ln2)) for large |x|, else
+ * := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x|>2, else
+ * := sign(x)*log1p(|x| + x^2/(1 + sqrt(1+x^2)))
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const double
+#else
+static double
+#endif
+one = 1.00000000000000000000e+00, /* 0x3FF00000, 0x00000000 */
+ln2 = 6.93147180559945286227e-01, /* 0x3FE62E42, 0xFEFA39EF */
+huge= 1.00000000000000000000e+300;
+
+#ifdef __STDC__
+ double __asinh(double x)
+#else
+ double __asinh(x)
+ double x;
+#endif
+{
+ double t,w;
+ int32_t hx,ix;
+ GET_HIGH_WORD(hx,x);
+ ix = hx&0x7fffffff;
+ if(ix>=0x7ff00000) return x+x; /* x is inf or NaN */
+ if(ix< 0x3e300000) { /* |x|<2**-28 */
+ if(huge+x>one) return x; /* return x inexact except 0 */
+ }
+ if(ix>0x41b00000) { /* |x| > 2**28 */
+ w = __ieee754_log(fabs(x))+ln2;
+ } else if (ix>0x40000000) { /* 2**28 > |x| > 2.0 */
+ t = fabs(x);
+ w = __ieee754_log(2.0*t+one/(__ieee754_sqrt(x*x+one)+t));
+ } else { /* 2.0 > |x| > 2**-28 */
+ t = x*x;
+ w =__log1p(fabs(x)+t/(one+__ieee754_sqrt(one+t)));
+ }
+ if(hx>0) return w; else return -w;
+}
+weak_alias (__asinh, asinh)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__asinh, __asinhl)
+weak_alias (__asinh, asinhl)
+#endif