diff options
| author | Paul E. Murphy <murphyp@linux.vnet.ibm.com> | 2020-02-07 14:07:01 -0600 |
|---|---|---|
| committer | Paul E. Murphy <murphyp@linux.vnet.ibm.com> | 2020-02-21 08:24:36 -0600 |
| commit | a92ac9f494b2a7d59a1f54ba79c569a35a6da005 (patch) | |
| tree | e32c49c2f71a90e66a9f75647e846ba6d8b47775 /sysdeps/ieee754/ldbl-128ibm/ieee754.h | |
| parent | bb05281822d406afdf5fa0457a91f77a5f5260f1 (diff) | |
| download | glibc-a92ac9f494b2a7d59a1f54ba79c569a35a6da005.zip glibc-a92ac9f494b2a7d59a1f54ba79c569a35a6da005.tar.gz glibc-a92ac9f494b2a7d59a1f54ba79c569a35a6da005.tar.bz2 | |
ldbl-128ibm: make ieee754.h work with IEEE 128 long double
Instead of attempting something more creative, just copy
the small struct from ldbl-128 and enable it when IEEE
long double is present, and update the ibm long double
variant if supported.
Likewise, provide a shadow copy of math_ldbl.h to prevent
the ibm128 specific long double header from poisoning
unrelated files due to it's usage in math_private.h.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/ieee754.h')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/ieee754.h | 68 |
1 files changed, 66 insertions, 2 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/ieee754.h b/sysdeps/ieee754/ldbl-128ibm/ieee754.h index 87c64fc..fe4892d 100644 --- a/sysdeps/ieee754/ldbl-128ibm/ieee754.h +++ b/sysdeps/ieee754/ldbl-128ibm/ieee754.h @@ -21,6 +21,7 @@ #include <features.h> #include <bits/endian.h> +#include <bits/floatn.h> __BEGIN_DECLS @@ -111,6 +112,65 @@ union ieee754_double #define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ +#if __LONG_DOUBLE_USES_FLOAT128 == 1 +/* long double is IEEE 128 bit */ +union ieee854_long_double + { + long double d; + + /* This is the IEEE 854 quad-precision format. */ + struct + { +#if __BYTE_ORDER == __BIG_ENDIAN + unsigned int negative:1; + unsigned int exponent:15; + /* Together these comprise the mantissa. */ + unsigned int mantissa0:16; + unsigned int mantissa1:32; + unsigned int mantissa2:32; + unsigned int mantissa3:32; +#endif /* Big endian. */ +#if __BYTE_ORDER == __LITTLE_ENDIAN + /* Together these comprise the mantissa. */ + unsigned int mantissa3:32; + unsigned int mantissa2:32; + unsigned int mantissa1:32; + unsigned int mantissa0:16; + unsigned int exponent:15; + unsigned int negative:1; +#endif /* Little endian. */ + } ieee; + + /* This format makes it easier to see if a NaN is a signalling NaN. */ + struct + { +#if __BYTE_ORDER == __BIG_ENDIAN + unsigned int negative:1; + unsigned int exponent:15; + unsigned int quiet_nan:1; + /* Together these comprise the mantissa. */ + unsigned int mantissa0:15; + unsigned int mantissa1:32; + unsigned int mantissa2:32; + unsigned int mantissa3:32; +#else + /* Together these comprise the mantissa. */ + unsigned int mantissa3:32; + unsigned int mantissa2:32; + unsigned int mantissa1:32; + unsigned int mantissa0:15; + unsigned int quiet_nan:1; + unsigned int exponent:15; + unsigned int negative:1; +#endif + } ieee_nan; + }; + +#define IEEE854_LONG_DOUBLE_BIAS 0x3fff /* Added to exponent. */ +#endif + + +#if __LONG_DOUBLE_USES_FLOAT128 == 0 || __GNUC_PREREQ (7, 0) /* IBM extended format for long double. Each long double is made up of two IEEE doubles. The value of the @@ -121,12 +181,16 @@ union ieee754_double -0.0. No other requirements are made; so, for example, 1.0 may be represented as (1.0, +0.0) or (1.0, -0.0), and the low part of a NaN is don't-care. */ - union ibm_extended_long_double { - long double ld; +# if __LONG_DOUBLE_USES_FLOAT128 == 1 && __GNUC_PREREQ (7, 0) + __ibm128 ld; +# else + long double ld; +# endif union ieee754_double d[2]; }; +#endif __END_DECLS |