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* 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.
61 lines
1.5 KiB
C
61 lines
1.5 KiB
C
/* @(#)s_frexp.c 5.1 93/09/24 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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#if defined(LIBM_SCCS) && !defined(lint)
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static char rcsid[] = "$NetBSD: s_frexp.c,v 1.9 1995/05/10 20:47:24 jtc Exp $";
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#endif
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/*
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* for non-zero x
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* x = frexp(arg,&exp);
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* return a double fp quantity x such that 0.5 <= |x| <1.0
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* and the corresponding binary exponent "exp". That is
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* arg = x*2^exp.
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* If arg is inf, 0.0, or NaN, then frexp(arg,&exp) returns arg
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* with *exp=0.
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*/
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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static const double
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#else
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static double
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#endif
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two54 = 1.80143985094819840000e+16; /* 0x43500000, 0x00000000 */
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#ifdef __STDC__
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double __frexp(double x, int *eptr)
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#else
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double __frexp(x, eptr)
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double x; int *eptr;
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#endif
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{
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int32_t hx, ix, lx;
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EXTRACT_WORDS(hx,lx,x);
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ix = 0x7fffffff&hx;
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*eptr = 0;
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if(ix>=0x7ff00000||((ix|lx)==0)) return x; /* 0,inf,nan */
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if (ix<0x00100000) { /* subnormal */
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x *= two54;
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GET_HIGH_WORD(hx,x);
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ix = hx&0x7fffffff;
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*eptr = -54;
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}
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*eptr += (ix>>20)-1022;
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hx = (hx&0x800fffff)|0x3fe00000;
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SET_HIGH_WORD(x,hx);
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return x;
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}
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weak_alias (__frexp, frexp)
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