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author | Roland McGrath <roland@gnu.org> | 1996-03-05 21:41:30 +0000 |
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committer | Roland McGrath <roland@gnu.org> | 1996-03-05 21:41:30 +0000 |
commit | f7eac6eb504f4baf13dbb4d26717942df050ebe6 (patch) | |
tree | 95ff129c06c7f6f246a5e2bfa489ba6382659d19 /sysdeps/libm-ieee754/s_frexp.c | |
parent | 1521668f2afae1dc2ef5d7ffaeb84353b36874dd (diff) | |
download | glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.zip glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.tar.gz glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.tar.bz2 |
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_frexp.c')
-rw-r--r-- | sysdeps/libm-ieee754/s_frexp.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_frexp.c b/sysdeps/libm-ieee754/s_frexp.c new file mode 100644 index 0000000..1f3bfce --- /dev/null +++ b/sysdeps/libm-ieee754/s_frexp.c @@ -0,0 +1,60 @@ +/* @(#)s_frexp.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_frexp.c,v 1.9 1995/05/10 20:47:24 jtc Exp $"; +#endif + +/* + * for non-zero x + * x = frexp(arg,&exp); + * return a double fp quantity x such that 0.5 <= |x| <1.0 + * and the corresponding binary exponent "exp". That is + * arg = x*2^exp. + * If arg is inf, 0.0, or NaN, then frexp(arg,&exp) returns arg + * with *exp=0. + */ + +#include "math.h" +#include "math_private.h" + +#ifdef __STDC__ +static const double +#else +static double +#endif +two54 = 1.80143985094819840000e+16; /* 0x43500000, 0x00000000 */ + +#ifdef __STDC__ + double __frexp(double x, int *eptr) +#else + double __frexp(x, eptr) + double x; int *eptr; +#endif +{ + int32_t hx, ix, lx; + EXTRACT_WORDS(hx,lx,x); + ix = 0x7fffffff&hx; + *eptr = 0; + if(ix>=0x7ff00000||((ix|lx)==0)) return x; /* 0,inf,nan */ + if (ix<0x00100000) { /* subnormal */ + x *= two54; + GET_HIGH_WORD(hx,x); + ix = hx&0x7fffffff; + *eptr = -54; + } + *eptr += (ix>>20)-1022; + hx = (hx&0x800fffff)|0x3fe00000; + SET_HIGH_WORD(x,hx); + return x; +} +weak_alias (__frexp, frexp) |