| /* s_rintl.c -- long double version of s_rint.c. |
| * Conversion to long double by Ulrich Drepper, |
| * Cygnus Support, drepper@cygnus.com. |
| */ |
| /* Adapted for use as nearbyint by Ulrich Drepper <drepper@cygnus.com>. */ |
| |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| /* |
| * rintl(x) |
| * Return x rounded to integral value according to the prevailing |
| * rounding mode. |
| * Method: |
| * Using floating addition. |
| * Exception: |
| * Inexact flag raised if x not equal to rintl(x). |
| */ |
| |
| #include <fenv.h> |
| #include "math.h" |
| #include "math_private.h" |
| |
| #ifdef __STDC__ |
| static const long double |
| #else |
| static long double |
| #endif |
| TWO63[2]={ |
| 9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */ |
| -9.223372036854775808000000e+18 /* 0xC03E, 0x00000000, 0x00000000 */ |
| }; |
| |
| #ifdef __STDC__ |
| long double __nearbyintl(long double x) |
| #else |
| long double __nearbyintl(x) |
| long double x; |
| #endif |
| { |
| fenv_t env; |
| int32_t se,j0,sx; |
| u_int32_t i,i0,i1; |
| long double w,t; |
| GET_LDOUBLE_WORDS(se,i0,i1,x); |
| sx = (se>>15)&1; |
| j0 = (se&0x7fff)-0x3fff; |
| if(j0<31) { |
| if(j0<0) { |
| if(((se&0x7fff)|i0|i1)==0) return x; |
| i1 |= i0; |
| i0 &= 0xe0000000; |
| i0 |= (i1|-i1)&0x80000000; |
| SET_LDOUBLE_MSW(x,i0); |
| feholdexcept (&env); |
| w = TWO63[sx]+x; |
| t = w-TWO63[sx]; |
| fesetenv (&env); |
| GET_LDOUBLE_EXP(i0,t); |
| SET_LDOUBLE_EXP(t,(i0&0x7fff)|(sx<<15)); |
| return t; |
| } else { |
| i = (0x7fffffff)>>j0; |
| if(((i0&i)|i1)==0) return x; /* x is integral */ |
| i>>=1; |
| if(((i0&i)|i1)!=0) { |
| if (j0==30) i1 = 0x40000000; else |
| i0 = (i0&(~i))|((0x20000000)>>j0); |
| } |
| } |
| } else if (j0>62) { |
| if(j0==0x4000) return x+x; /* inf or NaN */ |
| else return x; /* x is integral */ |
| } else { |
| i = ((u_int32_t)(0xffffffff))>>(j0-31); |
| if((i1&i)==0) return x; /* x is integral */ |
| i>>=1; |
| if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(j0-31)); |
| } |
| SET_LDOUBLE_WORDS(x,se,i0,i1); |
| feholdexcept (&env); |
| w = TWO63[sx]+x; |
| t = w-TWO63[sx]; |
| fesetenv (&env); |
| return t; |
| } |
| weak_alias (__nearbyintl, nearbyintl) |
