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 */
22
23#define NO_MATH_REDIRECT
24#include <math.h>
25#include <math_private.h>
26#include <libm-alias-float.h>
27#include <math-use-builtins.h>
28
29float
30__floorf (float x)
31{
32#if USE_FLOORF_BUILTIN
33 return __builtin_floorf (x);
34#else
35 /* Use generic implementation. */
36 int32_t i0, j0;
37 uint32_t i;
38 GET_FLOAT_WORD (i0, x);
39 j0 = ((i0 >> 23) & 0xff) - 0x7f;
40 if (j0 < 23)
41 {
42 if (j0 < 0)
43 {
44 /* return 0 * sign (x) if |x| < 1 */
45 if (i0 >= 0)
46 i0 = 0;
47 else if ((i0 & 0x7fffffff) != 0)
48 i0 = 0xbf800000;
49 }
50 else
51 {
52 i = (0x007fffff) >> j0;
53 if ((i0 & i) == 0)
54 return x; /* x is integral */
55 if (i0 < 0)
56 i0 += (0x00800000) >> j0;
57 i0 &= (~i);
58 }
59 }
60 else
61 {
62 if (__glibc_unlikely (j0 == 0x80))
63 return x + x; /* inf or NaN */
64 else
65 return x; /* x is integral */
66 }
67 SET_FLOAT_WORD (x, i0);
68 return x;
69#endif /* ! USE_FLOORF_BUILTIN */
70}
71#ifndef __floorf
72libm_alias_float (__floor, floor)
73#endif
74