|
Last change
on this file was 2006, checked in by bird, 21 years ago |
|
Initial revision
|
-
Property cvs2svn:cvs-rev
set to
1.1
-
Property svn:eol-style
set to
native
-
Property svn:executable
set to
*
|
|
File size:
932 bytes
|
| Line | |
|---|
| 1 | /* s_logbf.c -- float version of s_logb.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
|
|---|
| 17 | static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_logbf.c,v 1.7 2002/05/28 18:15:04 alfred Exp $";
|
|---|
| 18 | #endif
|
|---|
| 19 |
|
|---|
| 20 | #include "math.h"
|
|---|
| 21 | #include "math_private.h"
|
|---|
| 22 |
|
|---|
| 23 | float
|
|---|
| 24 | logbf(float x)
|
|---|
| 25 | {
|
|---|
| 26 | int32_t ix;
|
|---|
| 27 | GET_FLOAT_WORD(ix,x);
|
|---|
| 28 | ix &= 0x7fffffff; /* high |x| */
|
|---|
| 29 | if(ix==0) return (float)-1.0/fabsf(x);
|
|---|
| 30 | if(ix>=0x7f800000) return x*x;
|
|---|
| 31 | if((ix>>=23)==0) /* IEEE 754 logb */
|
|---|
| 32 | return -126.0;
|
|---|
| 33 | else
|
|---|
| 34 | return (float) (ix-127);
|
|---|
| 35 | }
|
|---|
Note:
See
TracBrowser
for help on using the repository browser.
