diff options
Diffstat (limited to 'src/third_party/js-1.7/fdlibm/s_modf.c')
| -rw-r--r-- | src/third_party/js-1.7/fdlibm/s_modf.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/src/third_party/js-1.7/fdlibm/s_modf.c b/src/third_party/js-1.7/fdlibm/s_modf.c new file mode 100644 index 00000000000..3b182bd3bbf --- /dev/null +++ b/src/third_party/js-1.7/fdlibm/s_modf.c @@ -0,0 +1,132 @@ +/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- + * + * ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0/LGPL 2.1 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is Mozilla Communicator client code, released + * March 31, 1998. + * + * The Initial Developer of the Original Code is + * Sun Microsystems, Inc. + * Portions created by the Initial Developer are Copyright (C) 1998 + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * + * Alternatively, the contents of this file may be used under the terms of + * either of the GNU General Public License Version 2 or later (the "GPL"), + * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), + * in which case the provisions of the GPL or the LGPL are applicable instead + * of those above. If you wish to allow use of your version of this file only + * under the terms of either the GPL or the LGPL, and not to allow others to + * use your version of this file under the terms of the MPL, indicate your + * decision by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL or the LGPL. If you do not delete + * the provisions above, a recipient may use your version of this file under + * the terms of any one of the MPL, the GPL or the LGPL. + * + * ***** END LICENSE BLOCK ***** */ + +/* @(#)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 fd_modf(double x, double *iptr) +#else + double fd_modf(x, iptr) + double x,*iptr; +#endif +{ + int i0,i1,j0; + unsigned i; + fd_twoints u; + u.d = x; + i0 = __HI(u); /* high x */ + i1 = __LO(u); /* low x */ + j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */ + if(j0<20) { /* integer part in high x */ + if(j0<0) { /* |x|<1 */ + u.d = *iptr; + __HI(u) = i0&0x80000000; + __LO(u) = 0; /* *iptr = +-0 */ + *iptr = u.d; + return x; + } else { + i = (0x000fffff)>>j0; + if(((i0&i)|i1)==0) { /* x is integral */ + *iptr = x; + u.d = x; + __HI(u) &= 0x80000000; + __LO(u) = 0; /* return +-0 */ + x = u.d; + return x; + } else { + u.d = *iptr; + __HI(u) = i0&(~i); + __LO(u) = 0; + *iptr = u.d; + return x - *iptr; + } + } + } else if (j0>51) { /* no fraction part */ + *iptr = x*one; + u.d = x; + __HI(u) &= 0x80000000; + __LO(u) = 0; /* return +-0 */ + x = u.d; + return x; + } else { /* fraction part in low x */ + i = ((unsigned)(0xffffffff))>>(j0-20); + if((i1&i)==0) { /* x is integral */ + *iptr = x; + u.d = x; + __HI(u) &= 0x80000000; + __LO(u) = 0; /* return +-0 */ + x = u.d; + return x; + } else { + u.d = *iptr; + __HI(u) = i0; + __LO(u) = i1&(~i); + *iptr = u.d; + return x - *iptr; + } + } +} |