diff options
Diffstat (limited to 'libm/s_floorf.c')
| -rw-r--r-- | libm/s_floorf.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/libm/s_floorf.c b/libm/s_floorf.c new file mode 100644 index 000000000..e8822b088 --- /dev/null +++ b/libm/s_floorf.c @@ -0,0 +1,71 @@ +/* s_floorf.c -- float version of s_floor.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. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: s_floorf.c,v 1.4 1995/05/10 20:47:22 jtc Exp $"; +#endif + +/* + * floorf(x) + * Return x rounded toward -inf to integral value + * Method: + * Bit twiddling. + * Exception: + * Inexact flag raised if x not equal to floorf(x). + */ + +#include "math.h" +#include "math_private.h" + +#ifdef __STDC__ +static const float huge = 1.0e30; +#else +static float huge = 1.0e30; +#endif + +#ifdef __STDC__ + float __floorf(float x) +#else + float __floorf(x) + float x; +#endif +{ + int32_t i0,j0; + u_int32_t i; + GET_FLOAT_WORD(i0,x); + j0 = ((i0>>23)&0xff)-0x7f; + if(j0<23) { + if(j0<0) { /* raise inexact if x != 0 */ + if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */ + if(i0>=0) {i0=0;} + else if((i0&0x7fffffff)!=0) + { i0=0xbf800000;} + } + } else { + i = (0x007fffff)>>j0; + if((i0&i)==0) return x; /* x is integral */ + if(huge+x>(float)0.0) { /* raise inexact flag */ + if(i0<0) i0 += (0x00800000)>>j0; + i0 &= (~i); + } + } + } else { + if(j0==0x80) return x+x; /* inf or NaN */ + else return x; /* x is integral */ + } + SET_FLOAT_WORD(x,i0); + return x; +} +weak_alias (__floorf, floorf) |