1 | /* s_modff.c -- float version of s_modf.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 | #include <math.h> |
17 | #include <math_private.h> |
18 | #include <libm-alias-float.h> |
19 | |
20 | static const float one = 1.0; |
21 | |
22 | float |
23 | __modff(float x, float *iptr) |
24 | { |
25 | int32_t i0,j0; |
26 | uint32_t i; |
27 | GET_FLOAT_WORD(i0,x); |
28 | j0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */ |
29 | if(__builtin_expect(j0<23, 1)) { /* integer part in x */ |
30 | if(j0<0) { /* |x|<1 */ |
31 | SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */ |
32 | return x; |
33 | } else { |
34 | i = (0x007fffff)>>j0; |
35 | if((i0&i)==0) { /* x is integral */ |
36 | uint32_t ix; |
37 | *iptr = x; |
38 | GET_FLOAT_WORD(ix,x); |
39 | SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ |
40 | return x; |
41 | } else { |
42 | SET_FLOAT_WORD(*iptr,i0&(~i)); |
43 | return x - *iptr; |
44 | } |
45 | } |
46 | } else { /* no fraction part */ |
47 | *iptr = x*one; |
48 | /* We must handle NaNs separately. */ |
49 | if (j0 == 0x80 && (i0 & 0x7fffff)) |
50 | return x*one; |
51 | SET_FLOAT_WORD(x,i0&0x80000000); /* return +-0 */ |
52 | return x; |
53 | } |
54 | } |
55 | libm_alias_float (__modf, modf) |
56 | |