s_modff.c revision 21673
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 17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_modff.c 21673 1997-01-14 07:20:47Z jkh $"; 18#endif 19 20#include "math.h" 21#include "math_private.h" 22 23#ifdef __STDC__ 24static const float one = 1.0; 25#else 26static float one = 1.0; 27#endif 28 29#ifdef __STDC__ 30 float modff(float x, float *iptr) 31#else 32 float modff(x, iptr) 33 float x,*iptr; 34#endif 35{ 36 int32_t i0,j0; 37 u_int32_t i; 38 GET_FLOAT_WORD(i0,x); 39 j0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */ 40 if(j0<23) { /* integer part in x */ 41 if(j0<0) { /* |x|<1 */ 42 SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */ 43 return x; 44 } else { 45 i = (0x007fffff)>>j0; 46 if((i0&i)==0) { /* x is integral */ 47 u_int32_t ix; 48 *iptr = x; 49 GET_FLOAT_WORD(ix,x); 50 SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ 51 return x; 52 } else { 53 SET_FLOAT_WORD(*iptr,i0&(~i)); 54 return x - *iptr; 55 } 56 } 57 } else { /* no fraction part */ 58 u_int32_t ix; 59 *iptr = x*one; 60 GET_FLOAT_WORD(ix,x); 61 SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ 62 return x; 63 } 64} 65