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author | Zack Weinberg <zackw@panix.com> | 2017-06-08 15:39:03 -0400 |
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committer | Zack Weinberg <zackw@panix.com> | 2017-06-08 15:39:03 -0400 |
commit | 5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch) | |
tree | 4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c | |
parent | 199fc19d3aaaf57944ef036e15904febe877fc93 (diff) | |
download | glibc-5046dbb4a7eba5eccfd258f92f4735c9ffc8d069.tar.gz |
Prepare for radical source tree reorganization.zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c')
-rw-r--r-- | REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c b/REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c new file mode 100644 index 0000000000..f70702b29c --- /dev/null +++ b/REORG.TODO/sysdeps/ieee754/flt-32/s_tanhf.c @@ -0,0 +1,62 @@ +/* s_tanhf.c -- float version of s_tanh.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. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: s_tanhf.c,v 1.4 1995/05/10 20:48:24 jtc Exp $"; +#endif + +#include <float.h> +#include <math.h> +#include <math_private.h> + +static const float one=1.0, two=2.0, tiny = 1.0e-30; + +float __tanhf(float x) +{ + float t,z; + int32_t jx,ix; + + GET_FLOAT_WORD(jx,x); + ix = jx&0x7fffffff; + + /* x is INF or NaN */ + if(ix>=0x7f800000) { + if (jx>=0) return one/x+one; /* tanh(+-inf)=+-1 */ + else return one/x-one; /* tanh(NaN) = NaN */ + } + + /* |x| < 22 */ + if (ix < 0x41b00000) { /* |x|<22 */ + if (ix == 0) + return x; /* x == +-0 */ + if (ix<0x24000000) /* |x|<2**-55 */ + { + math_check_force_underflow (x); + return x*(one+x); /* tanh(small) = small */ + } + if (ix>=0x3f800000) { /* |x|>=1 */ + t = __expm1f(two*fabsf(x)); + z = one - two/(t+two); + } else { + t = __expm1f(-two*fabsf(x)); + z= -t/(t+two); + } + /* |x| > 22, return +-1 */ + } else { + z = one - tiny; /* raised inexact flag */ + } + return (jx>=0)? z: -z; +} +weak_alias (__tanhf, tanhf) |