URL
https://opencores.org/ocsvn/openrisc/openrisc/trunk
Subversion Repositories openrisc
[/] [openrisc/] [trunk/] [rtos/] [ecos-3.0/] [packages/] [language/] [c/] [libm/] [current/] [src/] [double/] [portable-api/] [s_modf.c] - Rev 794
Go to most recent revision | Compare with Previous | Blame | View Log
//=========================================================================== // // s_modf.c // // Part of the standard mathematical function library // //=========================================================================== // ####ECOSGPLCOPYRIGHTBEGIN#### // ------------------------------------------- // This file is part of eCos, the Embedded Configurable Operating System. // Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. // // eCos is free software; you can redistribute it and/or modify it under // the terms of the GNU General Public License as published by the Free // Software Foundation; either version 2 or (at your option) any later // version. // // eCos is distributed in the hope that it will be useful, but WITHOUT // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License // for more details. // // You should have received a copy of the GNU General Public License // along with eCos; if not, write to the Free Software Foundation, Inc., // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. // // As a special exception, if other files instantiate templates or use // macros or inline functions from this file, or you compile this file // and link it with other works to produce a work based on this file, // this file does not by itself cause the resulting work to be covered by // the GNU General Public License. However the source code for this file // must still be made available in accordance with section (3) of the GNU // General Public License v2. // // This exception does not invalidate any other reasons why a work based // on this file might be covered by the GNU General Public License. // ------------------------------------------- // ####ECOSGPLCOPYRIGHTEND#### //=========================================================================== //#####DESCRIPTIONBEGIN#### // // Author(s): jlarmour // Contributors: jlarmour // Date: 1998-02-13 // Purpose: // Description: // Usage: // //####DESCRIPTIONEND#### // //=========================================================================== // CONFIGURATION #include <pkgconf/libm.h> // Configuration header // Include the Math library? #ifdef CYGPKG_LIBM // Derived from code with the following copyright /* @(#)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 "mathincl/fdlibm.h" static const double one = 1.0; double modf(double x, double *iptr) { int i0,i1,j0; unsigned i; i0 = CYG_LIBM_HI(x); /* high x */ i1 = CYG_LIBM_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 */ CYG_LIBM_HIp(iptr) = i0&0x80000000; CYG_LIBM_LOp(iptr) = 0; /* *iptr = +-0 */ return x; } else { i = (0x000fffff)>>j0; if(((i0&i)|i1)==0) { /* x is integral */ *iptr = x; CYG_LIBM_HI(x) &= 0x80000000; CYG_LIBM_LO(x) = 0; /* return +-0 */ return x; } else { CYG_LIBM_HIp(iptr) = i0&(~i); CYG_LIBM_LOp(iptr) = 0; return x - *iptr; } } } else if (j0>51) { /* no fraction part */ *iptr = x*one; CYG_LIBM_HI(x) &= 0x80000000; CYG_LIBM_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; CYG_LIBM_HI(x) &= 0x80000000; CYG_LIBM_LO(x) = 0; /* return +-0 */ return x; } else { CYG_LIBM_HIp(iptr) = i0; CYG_LIBM_LOp(iptr) = i1&(~i); return x - *iptr; } } } #endif // ifdef CYGPKG_LIBM // EOF s_modf.c
Go to most recent revision | Compare with Previous | Blame | View Log