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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_rint.c | |
parent | 1521668f2afae1dc2ef5d7ffaeb84353b36874dd (diff) | |
download | glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.tar glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.tar.gz glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.tar.bz2 glibc-f7eac6eb504f4baf13dbb4d26717942df050ebe6.zip |
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_rint.c')
-rw-r--r-- | sysdeps/libm-ieee754/s_rint.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_rint.c b/sysdeps/libm-ieee754/s_rint.c new file mode 100644 index 0000000000..e24feaf1ac --- /dev/null +++ b/sysdeps/libm-ieee754/s_rint.c @@ -0,0 +1,87 @@ +/* @(#)s_rint.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_rint.c,v 1.8 1995/05/10 20:48:04 jtc Exp $"; +#endif + +/* + * rint(x) + * Return x rounded to integral value according to the prevailing + * rounding mode. + * Method: + * Using floating addition. + * Exception: + * Inexact flag raised if x not equal to rint(x). + */ + +#include "math.h" +#include "math_private.h" + +#ifdef __STDC__ +static const double +#else +static double +#endif +TWO52[2]={ + 4.50359962737049600000e+15, /* 0x43300000, 0x00000000 */ + -4.50359962737049600000e+15, /* 0xC3300000, 0x00000000 */ +}; + +#ifdef __STDC__ + double __rint(double x) +#else + double __rint(x) + double x; +#endif +{ + int32_t i0,j0,sx; + u_int32_t i,i1; + double w,t; + EXTRACT_WORDS(i0,i1,x); + sx = (i0>>31)&1; + j0 = ((i0>>20)&0x7ff)-0x3ff; + if(j0<20) { + if(j0<0) { + if(((i0&0x7fffffff)|i1)==0) return x; + i1 |= (i0&0x0fffff); + i0 &= 0xfffe0000; + i0 |= ((i1|-i1)>>12)&0x80000; + SET_HIGH_WORD(x,i0); + w = TWO52[sx]+x; + t = w-TWO52[sx]; + GET_HIGH_WORD(i0,t); + SET_HIGH_WORD(t,(i0&0x7fffffff)|(sx<<31)); + return t; + } else { + i = (0x000fffff)>>j0; + if(((i0&i)|i1)==0) return x; /* x is integral */ + i>>=1; + if(((i0&i)|i1)!=0) { + if(j0==19) i1 = 0x40000000; else + i0 = (i0&(~i))|((0x20000)>>j0); + } + } + } else if (j0>51) { + if(j0==0x400) return x+x; /* inf or NaN */ + else return x; /* x is integral */ + } else { + i = ((u_int32_t)(0xffffffff))>>(j0-20); + if((i1&i)==0) return x; /* x is integral */ + i>>=1; + if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(j0-20)); + } + INSERT_WORDS(x,i0,i1); + w = TWO52[sx]+x; + return w-TWO52[sx]; +} +weak_alias (__rint, rint) |