1*627f7eb2Smrg /* s_nearbyintl.c -- long double version of s_nearbyint.c.
2*627f7eb2Smrg * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
3*627f7eb2Smrg */
4*627f7eb2Smrg
5*627f7eb2Smrg /*
6*627f7eb2Smrg * ====================================================
7*627f7eb2Smrg * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8*627f7eb2Smrg *
9*627f7eb2Smrg * Developed at SunPro, a Sun Microsystems, Inc. business.
10*627f7eb2Smrg * Permission to use, copy, modify, and distribute this
11*627f7eb2Smrg * software is freely granted, provided that this notice
12*627f7eb2Smrg * is preserved.
13*627f7eb2Smrg * ====================================================
14*627f7eb2Smrg */
15*627f7eb2Smrg
16*627f7eb2Smrg /*
17*627f7eb2Smrg * nearbyintq(x)
18*627f7eb2Smrg * Return x rounded to integral value according to the prevailing
19*627f7eb2Smrg * rounding mode.
20*627f7eb2Smrg * Method:
21*627f7eb2Smrg * Using floating addition.
22*627f7eb2Smrg * Exception:
23*627f7eb2Smrg * Inexact flag raised if x not equal to rintq(x).
24*627f7eb2Smrg */
25*627f7eb2Smrg
26*627f7eb2Smrg #include "quadmath-imp.h"
27*627f7eb2Smrg
28*627f7eb2Smrg static const __float128
29*627f7eb2Smrg TWO112[2]={
30*627f7eb2Smrg 5.19229685853482762853049632922009600E+33Q, /* 0x406F000000000000, 0 */
31*627f7eb2Smrg -5.19229685853482762853049632922009600E+33Q /* 0xC06F000000000000, 0 */
32*627f7eb2Smrg };
33*627f7eb2Smrg
nearbyintq(__float128 x)34*627f7eb2Smrg __float128 nearbyintq(__float128 x)
35*627f7eb2Smrg {
36*627f7eb2Smrg fenv_t env;
37*627f7eb2Smrg int64_t i0,j0,sx;
38*627f7eb2Smrg uint64_t i1 __attribute__ ((unused));
39*627f7eb2Smrg __float128 w,t;
40*627f7eb2Smrg GET_FLT128_WORDS64(i0,i1,x);
41*627f7eb2Smrg sx = (((uint64_t)i0)>>63);
42*627f7eb2Smrg j0 = ((i0>>48)&0x7fff)-0x3fff;
43*627f7eb2Smrg if(j0<112) {
44*627f7eb2Smrg if(j0<0) {
45*627f7eb2Smrg feholdexcept (&env);
46*627f7eb2Smrg w = TWO112[sx] + math_opt_barrier (x);
47*627f7eb2Smrg t = w-TWO112[sx];
48*627f7eb2Smrg math_force_eval (t);
49*627f7eb2Smrg fesetenv (&env);
50*627f7eb2Smrg GET_FLT128_MSW64(i0,t);
51*627f7eb2Smrg SET_FLT128_MSW64(t,(i0&0x7fffffffffffffffLL)|(sx<<63));
52*627f7eb2Smrg return t;
53*627f7eb2Smrg }
54*627f7eb2Smrg } else {
55*627f7eb2Smrg if(j0==0x4000) return x+x; /* inf or NaN */
56*627f7eb2Smrg else return x; /* x is integral */
57*627f7eb2Smrg }
58*627f7eb2Smrg feholdexcept (&env);
59*627f7eb2Smrg w = TWO112[sx] + math_opt_barrier (x);
60*627f7eb2Smrg t = w-TWO112[sx];
61*627f7eb2Smrg math_force_eval (t);
62*627f7eb2Smrg fesetenv (&env);
63*627f7eb2Smrg return t;
64*627f7eb2Smrg }
65