1/* s_floorf.c -- float version of s_floor.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16/*
17 * floorf(x)
18 * Return x rounded toward -inf to integral value
19 * Method:
20 * Bit twiddling.
21 * Exception:
22 * Inexact flag raised if x not equal to floorf(x).
23 */
24
25#include <math.h>
26#include <math_private.h>
27
28static const float huge = 1.0e30;
29
30float
31__floorf(float x)
32{
33 int32_t i0,j0;
34 u_int32_t i;
35 GET_FLOAT_WORD(i0,x);
36 j0 = ((i0>>23)&0xff)-0x7f;
37 if(j0<23) {
38 if(j0<0) { /* raise inexact if x != 0 */
39 math_force_eval(huge+x);/* return 0*sign(x) if |x|<1 */
40 if(i0>=0) {i0=0;}
41 else if((i0&0x7fffffff)!=0)
42 { i0=0xbf800000;}
43 } else {
44 i = (0x007fffff)>>j0;
45 if((i0&i)==0) return x; /* x is integral */
46 math_force_eval(huge+x); /* raise inexact flag */
47 if(i0<0) i0 += (0x00800000)>>j0;
48 i0 &= (~i);
49 }
50 } else {
51 if(__builtin_expect(j0==0x80, 0)) return x+x; /* inf or NaN */
52 else return x; /* x is integral */
53 }
54 SET_FLOAT_WORD(x,i0);
55 return x;
56}
57#ifndef __floorf
58weak_alias (__floorf, floorf)
59#endif
60