| The Android Open Source Project | a27d2ba | 2008-10-21 07:00:00 -0700 | [diff] [blame^] | 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 | #ifndef lint |
| 17 | static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_modff.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 | static const float one = 1.0; |
| 24 | |
| 25 | float |
| 26 | modff(float x, float *iptr) |
| 27 | { |
| 28 | int32_t i0,j0; |
| 29 | u_int32_t i; |
| 30 | GET_FLOAT_WORD(i0,x); |
| 31 | j0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */ |
| 32 | if(j0<23) { /* integer part in x */ |
| 33 | if(j0<0) { /* |x|<1 */ |
| 34 | SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */ |
| 35 | return x; |
| 36 | } else { |
| 37 | i = (0x007fffff)>>j0; |
| 38 | if((i0&i)==0) { /* x is integral */ |
| 39 | u_int32_t ix; |
| 40 | *iptr = x; |
| 41 | GET_FLOAT_WORD(ix,x); |
| 42 | SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ |
| 43 | return x; |
| 44 | } else { |
| 45 | SET_FLOAT_WORD(*iptr,i0&(~i)); |
| 46 | return x - *iptr; |
| 47 | } |
| 48 | } |
| 49 | } else { /* no fraction part */ |
| 50 | u_int32_t ix; |
| 51 | *iptr = x*one; |
| 52 | GET_FLOAT_WORD(ix,x); |
| 53 | SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ |
| 54 | return x; |
| 55 | } |
| 56 | } |