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_modf.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 libm/src/s_modf.c (limited to 'libm/src/s_modf.c') diff --git a/libm/src/s_modf.c b/libm/src/s_modf.c new file mode 100644 index 0000000..2ef62cc --- /dev/null +++ b/libm/src/s_modf.c @@ -0,0 +1,80 @@ + +/* @(#)s_modf.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. + * ==================================================== + */ + +/* + * modf(double x, double *iptr) + * return fraction part of x, and return x's integral part in *iptr. + * Method: + * Bit twiddling. + * + * Exception: + * No exception. + */ + +#include "fdlibm.h" + +#ifdef __STDC__ +static const double one = 1.0; +#else +static double one = 1.0; +#endif + +#ifdef __STDC__ + double modf(double x, double *iptr) +#else + double modf(x, iptr) + double x,*iptr; +#endif +{ + int i0,i1,j0; + unsigned i; + i0 = __HI(x); /* high x */ + i1 = __LO(x); /* low x */ + j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */ + if(j0<20) { /* integer part in high x */ + if(j0<0) { /* |x|<1 */ + __HIp(iptr) = i0&0x80000000; + __LOp(iptr) = 0; /* *iptr = +-0 */ + return x; + } else { + i = (0x000fffff)>>j0; + if(((i0&i)|i1)==0) { /* x is integral */ + *iptr = x; + __HI(x) &= 0x80000000; + __LO(x) = 0; /* return +-0 */ + return x; + } else { + __HIp(iptr) = i0&(~i); + __LOp(iptr) = 0; + return x - *iptr; + } + } + } else if (j0>51) { /* no fraction part */ + *iptr = x*one; + __HI(x) &= 0x80000000; + __LO(x) = 0; /* return +-0 */ + return x; + } else { /* fraction part in low x */ + i = ((unsigned)(0xffffffff))>>(j0-20); + if((i1&i)==0) { /* x is integral */ + *iptr = x; + __HI(x) &= 0x80000000; + __LO(x) = 0; /* return +-0 */ + return x; + } else { + __HIp(iptr) = i0; + __LOp(iptr) = i1&(~i); + return x - *iptr; + } + } +} -- cgit v1.2.3