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| author | Alan Modra <amodra@gmail.com> | 2013-08-17 18:24:58 +0930 |
|---|---|---|
| committer | Alan Modra <amodra@gmail.com> | 2013-10-04 10:32:36 +0930 |
| commit | 765714cafcad7e6168518c61111f07bd955a9fee (patch) | |
| tree | 27c4ab59ddc279114f3d0b7064a47317cb91c3ca /sysdeps/ieee754/ldbl-128ibm/s_isinfl.c | |
| parent | 4ebd120cd983c8d2ac7a234884b3ac6805d82973 (diff) | |
| download | glibc-765714cafcad7e6168518c61111f07bd955a9fee.zip glibc-765714cafcad7e6168518c61111f07bd955a9fee.tar.gz glibc-765714cafcad7e6168518c61111f07bd955a9fee.tar.bz2 | |
PowerPC floating point little-endian [3 of 15]
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.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_isinfl.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/s_isinfl.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_isinfl.c b/sysdeps/ieee754/ldbl-128ibm/s_isinfl.c index 5f5b014..6a72822 100644 --- a/sysdeps/ieee754/ldbl-128ibm/s_isinfl.c +++ b/sysdeps/ieee754/ldbl-128ibm/s_isinfl.c @@ -11,6 +11,7 @@ static char rcsid[] = "$NetBSD: $"; /* * isinfl(x) returns 1 if x is inf, -1 if x is -inf, else 0; * no branching! + * slightly dodgy in relying on signed shift right copying sign bit */ #include <math.h> @@ -20,12 +21,16 @@ static char rcsid[] = "$NetBSD: $"; int ___isinfl (long double x) { - int64_t hx,lx; - GET_LDOUBLE_WORDS64(hx,lx,x); - lx = (lx & 0x7fffffffffffffffLL); - lx |= (hx & 0x7fffffffffffffffLL) ^ 0x7ff0000000000000LL; - lx |= -lx; - return ~(lx >> 63) & (hx >> 62); + double xhi; + int64_t hx, mask; + + xhi = ldbl_high (x); + EXTRACT_WORDS64 (hx, xhi); + + mask = (hx & 0x7fffffffffffffffLL) ^ 0x7ff0000000000000LL; + mask |= -mask; + mask >>= 63; + return ~mask & (hx >> 62); } hidden_ver (___isinfl, __isinfl) #ifndef IS_IN_libm |