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#ifndef _MATH_PRIVATE_H_
#error "Never use <math_ldbl.h> directly; include <math_private.h> instead."
#endif
#include <sysdeps/ieee754/ldbl-128/math_ldbl.h>
#define EXTRACT_IBM_EXTENDED_MANTISSA(hi64, lo64, expnt, ibm_ext_ldbl) \
do \
{ \
/* We have 105 bits of mantissa plus one implicit digit. Since \
106 bits are representable without the rest using hexadecimal \
digits we use only the implicit digits for the number before \
the decimal point. */ \
unsigned long long hi, lo; \
int ediff; \
union ibm_extended_long_double eldbl; \
eldbl.d = ibm_ext_ldbl; \
expnt = eldbl.ieee.exponent - IBM_EXTENDED_LONG_DOUBLE_BIAS; \
\
lo = ((long long)eldbl.ieee.mantissa2 << 32) | eldbl.ieee.mantissa3; \
hi = ((long long)eldbl.ieee.mantissa0 << 32) | eldbl.ieee.mantissa1; \
/* If the lower double is not a denomal or zero then set the hidden \
53rd bit. */ \
if (eldbl.ieee.exponent2 > 0x001) \
{ \
lo |= (1ULL << 52); \
lo = lo << 7; /* pre-shift lo to match ieee854. */ \
/* The lower double is normalized separately from the upper. We \
may need to adjust the lower manitissa to reflect this. */ \
ediff = eldbl.ieee.exponent - eldbl.ieee.exponent2; \
if (ediff > 53) \
lo = lo >> (ediff-53); \
} \
hi |= (1ULL << 52); \
\
if ((eldbl.ieee.negative != eldbl.ieee.negative2) \
&& ((eldbl.ieee.exponent2 != 0) && (lo != 0LL))) \
{ \
hi--; \
lo = (1ULL << 60) - lo; \
if (hi < (1ULL << 52)) \
{ \
/* we have a borrow from the hidden bit, so shift left 1. */ \
hi = (hi << 1) | (lo >> 59); \
lo = 0xfffffffffffffffLL & (lo << 1); \
expnt--; \
} \
} \
lo64 = (hi << 60) | lo; \
hi64 = hi >> 4; \
} \
while (0)
#define INSERT_IBM_EXTENDED_MANTISSA(ibm_ext_ldbl, sign, expnt, hi64, lo64) \
do \
{ \
union ibm_extended_long_double u; \
unsigned long hidden2, lzcount; \
unsigned long long hi, lo; \
\
u.ieee.negative = sign; \
u.ieee.negative2 = sign; \
u.ieee.exponent = expnt + IBM_EXTENDED_LONG_DOUBLE_BIAS; \
u.ieee.exponent2 = expnt-53 + IBM_EXTENDED_LONG_DOUBLE_BIAS; \
/* Expect 113 bits (112 bits + hidden) right justified in two longs. \
The low order 53 bits (52 + hidden) go into the lower double */ \
lo = (lo64 >> 7)& ((1ULL << 53) - 1); \
hidden2 = (lo64 >> 59) & 1ULL; \
/* The high order 53 bits (52 + hidden) go into the upper double */ \
hi = (lo64 >> 60) & ((1ULL << 11) - 1); \
hi |= (hi64 << 4); \
\
if (lo != 0LL) \
{ \
/* hidden2 bit of low double controls rounding of the high double. \
If hidden2 is '1' then round up hi and adjust lo (2nd mantissa) \
plus change the sign of the low double to compensate. */ \
if (hidden2) \
{ \
hi++; \
u.ieee.negative2 = !sign; \
lo = (1ULL << 53) - lo; \
} \
/* The hidden bit of the lo mantissa is zero so we need to \
normalize the it for the low double. Shift it left until the \
hidden bit is '1' then adjust the 2nd exponent accordingly. */ \
\
if (sizeof (lo) == sizeof (long)) \
lzcount = __builtin_clzl (lo); \
else if ((lo >> 32) != 0) \
lzcount = __builtin_clzl ((long) (lo >> 32)); \
else \
lzcount = __builtin_clzl ((long) lo) + 32; \
lzcount = lzcount - 11; \
if (lzcount > 0) \
{ \
int expnt2 = u.ieee.exponent2 - lzcount; \
if (expnt2 >= 1) \
{ \
/* Not denormal. Normalize and set low exponent. */ \
lo = lo << lzcount; \
u.ieee.exponent2 = expnt2; \
} \
else \
{ \
/* Is denormal. */ \
lo = lo << (lzcount + expnt2); \
u.ieee.exponent2 = 0; \
} \
} \
} \
else \
{ \
u.ieee.negative2 = 0; \
u.ieee.exponent2 = 0; \
} \
\
u.ieee.mantissa3 = lo & ((1ULL << 32) - 1); \
u.ieee.mantissa2 = (lo >> 32) & ((1ULL << 20) - 1); \
u.ieee.mantissa1 = hi & ((1ULL << 32) - 1); \
u.ieee.mantissa0 = (hi >> 32) & ((1ULL << 20) - 1); \
ibm_ext_ldbl = u.d; \
} \
while (0)
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