diff options
Diffstat (limited to 'libm/src/s_rintf.c')
-rw-r--r-- | libm/src/s_rintf.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/libm/src/s_rintf.c b/libm/src/s_rintf.c new file mode 100644 index 0000000..677421a --- /dev/null +++ b/libm/src/s_rintf.c @@ -0,0 +1,52 @@ +/* s_rintf.c -- float version of s_rint.c. + * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. + */ + +/* + * ==================================================== + * 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. + * ==================================================== + */ + +#ifndef lint +static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_rintf.c,v 1.10 2005/12/03 09:00:29 bde Exp $"; +#endif + +#include <sys/types.h> +#include "math.h" +#include "math_private.h" + +static const float +TWO23[2]={ + 8.3886080000e+06, /* 0x4b000000 */ + -8.3886080000e+06, /* 0xcb000000 */ +}; + +float +rintf(float x) +{ + int32_t i0,j0,sx; + volatile float w,t; /* volatile works around gcc bug */ + GET_FLOAT_WORD(i0,x); + sx = (i0>>31)&1; + j0 = ((i0>>23)&0xff)-0x7f; + if(j0<23) { + if(j0<0) { + if((i0&0x7fffffff)==0) return x; + w = TWO23[sx]+x; + t = w-TWO23[sx]; + GET_FLOAT_WORD(i0,t); + SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31)); + return t; + } + w = TWO23[sx]+x; + return w-TWO23[sx]; + } + if(j0==0x80) return x+x; /* inf or NaN */ + else return x; /* x is integral */ +} |