Mercurial > nand-ecoscentric
view packages/language/c/libm/current/src/double/ieee754-api/w_exp.c @ 0:3111d98ba7b3 ecos-v1_1-release
Initial commit of eCos version 1.1
| author | jlarmour |
|---|---|
| date | Tue, 11 May 1999 11:16:07 +0000 |
| parents | |
| children | 443894e2e912 |
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//=========================================================================== // // w_exp.c // // Part of the standard mathematical function library // //=========================================================================== //####COPYRIGHTBEGIN#### // // ------------------------------------------- // The contents of this file are subject to the Cygnus eCos Public License // Version 1.0 (the "License"); you may not use this file except in // compliance with the License. You may obtain a copy of the License at // http://sourceware.cygnus.com/ecos // // 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 eCos - Embedded Cygnus Operating System, released // September 30, 1998. // // The Initial Developer of the Original Code is Cygnus. Portions created // by Cygnus are Copyright (C) 1998 Cygnus Solutions. All Rights Reserved. // ------------------------------------------- // //####COPYRIGHTEND#### //=========================================================================== //#####DESCRIPTIONBEGIN#### // // Author(s): jlarmour@cygnus.co.uk // Contributors: jlarmour@cygnus.co.uk // 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 /* @(#)w_exp.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. * ==================================================== */ /* * wrapper exp(x) */ #include "mathincl/fdlibm.h" static const double o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */ u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */ double exp(double x) /* wrapper exp */ { #ifdef CYGSEM_LIBM_COMPAT_IEEE_ONLY return __ieee754_exp(x); #else double z; z = __ieee754_exp(x); if(cyg_libm_get_compat_mode() == CYGNUM_LIBM_COMPAT_IEEE) return z; if(finite(x)) { if(x>o_threshold) return __kernel_standard(x,x,6); /* exp overflow */ else if(x<u_threshold) return __kernel_standard(x,x,7); /* exp underflow */ } return z; #endif } #endif // ifdef CYGPKG_LIBM // EOF w_exp.c
