s_modff.c revision 97409
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 97409 2002-05-28 17:51:46Z alfred $"; 18#endif 19 20#include "math.h" 21#include "math_private.h" 22 23static const float one = 1.0; 24 25 float modff(float x, float *iptr) 26{ 27 int32_t i0,j0; 28 u_int32_t i; 29 GET_FLOAT_WORD(i0,x); 30 j0 = ((i0>>23)&0xff)-0x7f; /* exponent of x */ 31 if(j0<23) { /* integer part in x */ 32 if(j0<0) { /* |x|<1 */ 33 SET_FLOAT_WORD(*iptr,i0&0x80000000); /* *iptr = +-0 */ 34 return x; 35 } else { 36 i = (0x007fffff)>>j0; 37 if((i0&i)==0) { /* x is integral */ 38 u_int32_t ix; 39 *iptr = x; 40 GET_FLOAT_WORD(ix,x); 41 SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ 42 return x; 43 } else { 44 SET_FLOAT_WORD(*iptr,i0&(~i)); 45 return x - *iptr; 46 } 47 } 48 } else { /* no fraction part */ 49 u_int32_t ix; 50 *iptr = x*one; 51 GET_FLOAT_WORD(ix,x); 52 SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */ 53 return x; 54 } 55} 56