1/* modfq.c -- __float128 version of s_modf.c. 2 * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. 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#include "quadmath-imp.h" 17 18static const __float128 one = 1.0; 19 20__float128 21modfq (__float128 x, __float128 *iptr) 22{ 23 int64_t i0,i1,j0; 24 uint64_t i; 25 GET_FLT128_WORDS64(i0,i1,x); 26 j0 = ((i0>>48)&0x7fff)-0x3fff; /* exponent of x */ 27 if(j0<48) { /* integer part in high x */ 28 if(j0<0) { /* |x|<1 */ 29 /* *iptr = +-0 */ 30 SET_FLT128_WORDS64(*iptr,i0&0x8000000000000000ULL,0); 31 return x; 32 } else { 33 i = (0x0000ffffffffffffLL)>>j0; 34 if(((i0&i)|i1)==0) { /* x is integral */ 35 *iptr = x; 36 /* return +-0 */ 37 SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0); 38 return x; 39 } else { 40 SET_FLT128_WORDS64(*iptr,i0&(~i),0); 41 return x - *iptr; 42 } 43 } 44 } else if (j0>111) { /* no fraction part */ 45 *iptr = x*one; 46 /* We must handle NaNs separately. */ 47 if (j0 == 0x4000 && ((i0 & 0x0000ffffffffffffLL) | i1)) 48 return x*one; 49 /* return +-0 */ 50 SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0); 51 return x; 52 } else { /* fraction part in low x */ 53 i = -1ULL>>(j0-48); 54 if((i1&i)==0) { /* x is integral */ 55 *iptr = x; 56 /* return +-0 */ 57 SET_FLT128_WORDS64(x,i0&0x8000000000000000ULL,0); 58 return x; 59 } else { 60 SET_FLT128_WORDS64(*iptr,i0,i1&(~i)); 61 return x - *iptr; 62 } 63 } 64} 65