From 8b1fadd6a89f12cbc81c5d621a75b91dd9eedec2 Mon Sep 17 00:00:00 2001 From: Pixel Date: Sat, 5 Feb 2011 11:06:07 -0800 Subject: Adding Sun's fdlibm, and libnix's scanf, tweaked to become an xscanf. Adding a few more libc inlined also. --- libm/src/s_rint.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 libm/src/s_rint.c (limited to 'libm/src/s_rint.c') diff --git a/libm/src/s_rint.c b/libm/src/s_rint.c new file mode 100644 index 0000000..3095e0d --- /dev/null +++ b/libm/src/s_rint.c @@ -0,0 +1,84 @@ + +/* @(#)s_rint.c 1.3 95/01/18 */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunSoft, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* + * 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 "fdlibm.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 +{ + int i0,j0,sx; + unsigned i,i1; + double w,t; + i0 = __HI(x); + sx = (i0>>31)&1; + i1 = __LO(x); + 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; + __HI(x)=i0; + w = TWO52[sx]+x; + t = w-TWO52[sx]; + i0 = __HI(t); + __HI(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 = ((unsigned)(0xffffffff))>>(j0-20); + if((i1&i)==0) return x; /* x is integral */ + i>>=1; + if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(j0-20)); + } + __HI(x) = i0; + __LO(x) = i1; + w = TWO52[sx]+x; + return w-TWO52[sx]; +} -- cgit v1.2.3