| /* s_frexpl.c -- long double version of s_frexp.c. |
| * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. |
| */ |
| |
| /* |
| * ==================================================== |
| * 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. |
| * ==================================================== |
| */ |
| |
| #if defined(LIBM_SCCS) && !defined(lint) |
| static char rcsid[] = "$NetBSD: $"; |
| #endif |
| |
| /* |
| * for non-zero x |
| * x = frexpl(arg,&exp); |
| * return a long double fp quantity x such that 0.5 <= |x| <1.0 |
| * and the corresponding binary exponent "exp". That is |
| * arg = x*2^exp. |
| * If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg |
| * with *exp=0. |
| */ |
| |
| #include "math.h" |
| #include "math_private.h" |
| #include <math_ldbl_opt.h> |
| |
| #ifdef __STDC__ |
| static const long double |
| #else |
| static long double |
| #endif |
| two107 = 162259276829213363391578010288128.0; /* 0x4670000000000000, 0 */ |
| |
| #ifdef __STDC__ |
| long double __frexpl(long double x, int *eptr) |
| #else |
| long double __frexpl(x, eptr) |
| long double x; int *eptr; |
| #endif |
| { |
| u_int64_t hx, lx, ix, ixl; |
| int64_t explo; |
| GET_LDOUBLE_WORDS64(hx,lx,x); |
| ixl = 0x7fffffffffffffffULL&lx; |
| ix = 0x7fffffffffffffffULL&hx; |
| *eptr = 0; |
| if(ix>=0x7ff0000000000000ULL||((ix|ixl)==0)) return x; /* 0,inf,nan */ |
| if (ix<0x0010000000000000ULL) { /* subnormal */ |
| x *= two107; |
| GET_LDOUBLE_MSW64(hx,x); |
| ix = hx&0x7fffffffffffffffULL; |
| *eptr = -107; |
| } |
| *eptr += (ix>>52)-1022; |
| |
| if (ixl != 0ULL) { |
| explo = (ixl>>52) - (ix>>52) + 0x3fe; |
| if ((ixl&0x7ff0000000000000ULL) == 0LL) { |
| /* the lower double is a denomal so we need to correct its |
| mantissa and perhaps its exponent. */ |
| int cnt; |
| |
| if (sizeof (ixl) == sizeof (long)) |
| cnt = __builtin_clzl (ixl); |
| else if ((ixl >> 32) != 0) |
| cnt = __builtin_clzl ((long) (ixl >> 32)); |
| else |
| cnt = __builtin_clzl ((long) ixl) + 32; |
| cnt = cnt - 12; |
| lx = (lx&0x8000000000000000ULL) | ((explo-cnt)<<52) |
| | ((ixl<<(cnt+1))&0x000fffffffffffffULL); |
| } else |
| lx = (lx&0x800fffffffffffffULL) | (explo<<52); |
| } else |
| lx = 0ULL; |
| |
| hx = (hx&0x800fffffffffffffULL) | 0x3fe0000000000000ULL; |
| SET_LDOUBLE_WORDS64(x,hx,lx); |
| return x; |
| } |
| #ifdef IS_IN_libm |
| long_double_symbol (libm, __frexpl, frexpl); |
| #else |
| long_double_symbol (libc, __frexpl, frexpl); |
| #endif |