1 /*
2  * ====================================================
3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
4  *
5  * Developed at SunPro, a Sun Microsystems, Inc. business.
6  * Permission to use, copy, modify, and distribute this
7  * software is freely granted, provided that this notice
8  * is preserved.
9  * ====================================================
10  */
11 
12 #include "fdlibm.h"
13 
14 #ifdef __STDC__
roundf(float x)15 	float roundf(float x)
16 #else
17 	float roundf(x)
18 	float x;
19 #endif
20 {
21   __uint32_t w;
22   /* Most significant word, least significant word. */
23   int exponent_less_127;
24 
25   GET_FLOAT_WORD(w, x);
26 
27   /* Extract exponent field. */
28   exponent_less_127 = (int)((w & 0x7f800000) >> 23) - 127;
29 
30   if (exponent_less_127 < 23)
31     {
32       if (exponent_less_127 < 0)
33         {
34           w &= 0x80000000;
35           if (exponent_less_127 == -1)
36             /* Result is +1.0 or -1.0. */
37             w |= ((__uint32_t)127 << 23);
38         }
39       else
40         {
41           unsigned int exponent_mask = 0x007fffff >> exponent_less_127;
42           if ((w & exponent_mask) == 0)
43             /* x has an integral value. */
44             return x;
45 
46           w += 0x00400000 >> exponent_less_127;
47           w &= ~exponent_mask;
48         }
49     }
50   else
51     {
52       if (exponent_less_127 == 128)
53         /* x is NaN or infinite. */
54         return x + x;
55       else
56         return x;
57     }
58   SET_FLOAT_WORD(x, w);
59   return x;
60 }
61 
62 #ifdef _DOUBLE_IS_32BITS
63 
64 #ifdef __STDC__
round(double x)65 	double round(double x)
66 #else
67 	double round(x)
68 	double x;
69 #endif
70 {
71 	return (double) roundf((float) x);
72 }
73 
74 #endif /* defined(_DOUBLE_IS_32BITS) */
75