mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-21 04:31:04 +08:00
765714cafc
http://sourceware.org/ml/libc-alpha/2013-08/msg00083.html Further replacement of ieee854 macros and unions. These files also have some optimisations for comparison against 0.0L, infinity and nan. Since the ABI specifies that the high double of an IBM long double pair is the value rounded to double, a high double of 0.0 means the low double must also be 0.0. The ABI also says that infinity and nan are encoded in the high double, with the low double unspecified. This means that tests for 0.0L, +/-Infinity and +/-NaN need only check the high double. * sysdeps/ieee754/ldbl-128ibm/e_atan2l.c (__ieee754_atan2l): Rewrite all uses of ieee854 long double macros and unions. Simplify tests for long doubles that are fully specified by the high double. * sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_ilogbl.c (__ieee754_ilogbl): Likewise. Remove dead code too. * sysdeps/ieee754/ldbl-128ibm/e_jnl.c (__ieee754_jnl): Likewise. (__ieee754_ynl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_log10l.c (__ieee754_log10l): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_logl.c (__ieee754_logl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise. Remove dead code too. * sysdeps/ieee754/ldbl-128ibm/k_tanl.c (__kernel_tanl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_frexpl.c (__frexpl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_isinf_nsl.c (__isinf_nsl): Likewise. Simplify. * sysdeps/ieee754/ldbl-128ibm/s_isinfl.c (___isinfl): Likewise. Simplify. * sysdeps/ieee754/ldbl-128ibm/s_log1pl.c (__log1pl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_modfl.c (__modfl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nextafterl.c (__nextafterl): Likewise. Comment on variable precision. * sysdeps/ieee754/ldbl-128ibm/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_remquol.c (__remquol): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_scalblnl.c (__scalblnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_scalbnl.c (__scalbnl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_tanhl.c (__tanhl): Likewise. * sysdeps/powerpc/fpu/libm-test-ulps: Adjust tan_towardzero ulps.
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/* 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>
|
|
|
|
static const long double
|
|
two107 = 162259276829213363391578010288128.0; /* 0x4670000000000000, 0 */
|
|
|
|
long double __frexpl(long double x, int *eptr)
|
|
{
|
|
uint64_t hx, lx, ix, ixl;
|
|
int64_t explo;
|
|
double xhi, xlo;
|
|
|
|
ldbl_unpack (x, &xhi, &xlo);
|
|
EXTRACT_WORDS64 (hx, xhi);
|
|
EXTRACT_WORDS64 (lx, xlo);
|
|
ixl = 0x7fffffffffffffffULL&lx;
|
|
ix = 0x7fffffffffffffffULL&hx;
|
|
*eptr = 0;
|
|
if(ix>=0x7ff0000000000000ULL||ix==0) return x; /* 0,inf,nan */
|
|
if (ix<0x0010000000000000ULL) { /* subnormal */
|
|
x *= two107;
|
|
xhi = ldbl_high (x);
|
|
EXTRACT_WORDS64 (hx, xhi);
|
|
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 denormal 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;
|
|
INSERT_WORDS64 (xhi, hx);
|
|
INSERT_WORDS64 (xlo, lx);
|
|
x = ldbl_pack (xhi, xlo);
|
|
return x;
|
|
}
|
|
#ifdef IS_IN_libm
|
|
long_double_symbol (libm, __frexpl, frexpl);
|
|
#else
|
|
long_double_symbol (libc, __frexpl, frexpl);
|
|
#endif
|