1/* s_rintf.c -- float version of s_rint.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#ifndef lint
| 1/* s_rintf.c -- float version of s_rint.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#ifndef lint
|
17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_rintf.c 97413 2002-05-28 18:15:04Z alfred $";
| 17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_rintf.c 130285 2004-06-09 21:24:52Z das $";
|
18#endif
19
| 18#endif
19
|
| 20#include <sys/types.h>
|
20#include "math.h"
21#include "math_private.h"
22
| 21#include "math.h"
22#include "math_private.h"
23
|
23/*
24 * TWO23 is double instead of float to avoid a bug in gcc. Without
25 * this, gcc thinks that TWO23[sx]+x and w-TWO23[sx] already have float
26 * precision and doesn't clip them to float precision when they are
27 * assigned and returned.
28 */
29static const double
| 24static const float
|
30TWO23[2]={
31 8.3886080000e+06, /* 0x4b000000 */
32 -8.3886080000e+06, /* 0xcb000000 */
33};
34
35float
36rintf(float x)
37{
38 int32_t i0,j0,sx;
| 25TWO23[2]={
26 8.3886080000e+06, /* 0x4b000000 */
27 -8.3886080000e+06, /* 0xcb000000 */
28};
29
30float
31rintf(float x)
32{
33 int32_t i0,j0,sx;
|
39 u_int32_t i,i1;
40 float w,t;
| 34 volatile float w,t; /* volatile works around gcc bug */
|
41 GET_FLOAT_WORD(i0,x);
42 sx = (i0>>31)&1;
43 j0 = ((i0>>23)&0xff)-0x7f;
44 if(j0<23) {
45 if(j0<0) {
46 if((i0&0x7fffffff)==0) return x;
| 35 GET_FLOAT_WORD(i0,x);
36 sx = (i0>>31)&1;
37 j0 = ((i0>>23)&0xff)-0x7f;
38 if(j0<23) {
39 if(j0<0) {
40 if((i0&0x7fffffff)==0) return x;
|
47 i1 = (i0&0x07fffff);
48 i0 &= 0xfff00000;
49 i0 |= ((i1|-i1)>>9)&0x400000;
50 SET_FLOAT_WORD(x,i0);
| |
51 w = TWO23[sx]+x;
52 t = w-TWO23[sx];
| 41 w = TWO23[sx]+x;
42 t = w-TWO23[sx];
|
53 GET_FLOAT_WORD(i0,t);
54 SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
| |
55 return t;
| 43 return t;
|
56 } else {
57 i = (0x007fffff)>>j0;
58 if((i0&i)==0) return x; /* x is integral */
59 i>>=1;
60 if((i0&i)!=0) i0 = (i0&(~i))|((0x100000)>>j0);
| |
61 }
| 44 }
|
62 } else {
63 if(j0==0x80) return x+x; /* inf or NaN */
64 else return x; /* x is integral */
| 45 w = TWO23[sx]+x;
46 return w-TWO23[sx];
|
65 }
| 47 }
|
66 SET_FLOAT_WORD(x,i0);
67 w = TWO23[sx]+x;
68 return w-TWO23[sx];
| 48 if(j0==0x80) return x+x; /* inf or NaN */
49 else return x; /* x is integral */
|
69}
| 50}
|