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Diffstat (limited to 'libs/ode-0.16.1/ode/src/nextafterf.c')
| -rw-r--r-- | libs/ode-0.16.1/ode/src/nextafterf.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/libs/ode-0.16.1/ode/src/nextafterf.c b/libs/ode-0.16.1/ode/src/nextafterf.c new file mode 100644 index 0000000..78fbe31 --- /dev/null +++ b/libs/ode-0.16.1/ode/src/nextafterf.c @@ -0,0 +1,115 @@ +/************************************************************************* + * * + * Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith. * + * All rights reserved. Email: russ@q12.org Web: www.q12.org * + * * + * This library is free software; you can redistribute it and/or * + * modify it under the terms of EITHER: * + * (1) The GNU Lesser General Public License as published by the Free * + * Software Foundation; either version 2.1 of the License, or (at * + * your option) any later version. The text of the GNU Lesser * + * General Public License is included with this library in the * + * file LICENSE.TXT. * + * (2) The BSD-style license that is included with this library in * + * the file LICENSE-BSD.TXT. * + * * + * This library 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 files * + * LICENSE.TXT and LICENSE-BSD.TXT for more details. * + * * + *************************************************************************/ + +/* _nextafterf() implementation for MSVC */ + +#include <ode/common.h> +#include "config.h" + + +#if defined(_ODE__NEXTAFTERF_REQUIRED) + +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* A union which permits us to convert between a float and a 32 bit int. */ + +typedef union +{ + float value; + uint32 word; +} ieee_float_shape_type; + +/* Get a 32 bit int from a float. */ + +#define GET_FLOAT_WORD(i,d) \ + do { \ + volatile ieee_float_shape_type gf_u; \ + gf_u.value = (d); \ + (i) = gf_u.word; \ + } while (0) + +/* Set a float from a 32 bit int. */ + +#define SET_FLOAT_WORD(d,i) \ + do { \ + volatile ieee_float_shape_type sf_u; \ + sf_u.word = (i); \ + (d) = sf_u.value; \ + } while (0) + + +#undef nextafterf +float _nextafterf(float x, float y) +{ + int32 hx,hy,ix,iy; + + GET_FLOAT_WORD(hx,x); + GET_FLOAT_WORD(hy,y); + ix = hx&0x7fffffff; /* |x| */ + iy = hy&0x7fffffff; /* |y| */ + + if((ix>0x7f800000) || /* x is nan */ + (iy>0x7f800000)) /* y is nan */ + return x+y; + if(x==y) return x; /* x=y, return x */ + if(ix==0) { /* x == 0 */ + SET_FLOAT_WORD(x,(hy&0x80000000)|1);/* return +-minsubnormal */ + y = x*x; + if(y==x) return y; else return x; /* raise underflow flag */ + } + if(hx>=0) { /* x > 0 */ + if(hx>hy) { /* x > y, x -= ulp */ + hx -= 1; + } else { /* x < y, x += ulp */ + hx += 1; + } + } else { /* x < 0 */ + if(hy>=0||hx>hy){ /* x < y, x -= ulp */ + hx -= 1; + } else { /* x > y, x += ulp */ + hx += 1; + } + } + hy = hx&0x7f800000; + if(hy>=0x7f800000) return x+x; /* overflow */ + if(hy<0x00800000) { /* underflow */ + y = x*x; + if(y!=x) { /* raise underflow flag */ + SET_FLOAT_WORD(y,hx); + return y; + } + } + SET_FLOAT_WORD(x,hx); + return x; +} + + +#endif /* #if defined(_ODE__NEXTAFTERF_REQUIRED) */ |