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|
/* Software floating-point emulation.
Basic four-word fraction declaration and manipulation.
Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson (rth@cygnus.com),
Jakub Jelinek (jj@ultra.linux.cz),
David S. Miller (davem@redhat.com) and
Peter Maydell (pmaydell@chiark.greenend.org.uk).
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#define _FP_FRAC_DECL_4(X) _FP_W_TYPE X##_f[4]
#define _FP_FRAC_COPY_4(D,S) \
(D##_f[0] = S##_f[0], D##_f[1] = S##_f[1], \
D##_f[2] = S##_f[2], D##_f[3] = S##_f[3])
#define _FP_FRAC_SET_4(X,I) __FP_FRAC_SET_4(X, I)
#define _FP_FRAC_HIGH_4(X) (X##_f[3])
#define _FP_FRAC_LOW_4(X) (X##_f[0])
#define _FP_FRAC_WORD_4(X,w) (X##_f[w])
#define _FP_FRAC_SLL_4(X,N) \
do { \
_FP_I_TYPE _up, _down, _skip, _i; \
_skip = (N) / _FP_W_TYPE_SIZE; \
_up = (N) % _FP_W_TYPE_SIZE; \
_down = _FP_W_TYPE_SIZE - _up; \
if (!_up) \
for (_i = 3; _i >= _skip; --_i) \
X##_f[_i] = X##_f[_i-_skip]; \
else \
{ \
for (_i = 3; _i > _skip; --_i) \
X##_f[_i] = X##_f[_i-_skip] << _up \
| X##_f[_i-_skip-1] >> _down; \
X##_f[_i--] = X##_f[0] << _up; \
} \
for (; _i >= 0; --_i) \
X##_f[_i] = 0; \
} while (0)
/* This one was broken too */
#define _FP_FRAC_SRL_4(X,N) \
do { \
_FP_I_TYPE _up, _down, _skip, _i; \
_skip = (N) / _FP_W_TYPE_SIZE; \
_down = (N) % _FP_W_TYPE_SIZE; \
_up = _FP_W_TYPE_SIZE - _down; \
if (!_down) \
for (_i = 0; _i <= 3-_skip; ++_i) \
X##_f[_i] = X##_f[_i+_skip]; \
else \
{ \
for (_i = 0; _i < 3-_skip; ++_i) \
X##_f[_i] = X##_f[_i+_skip] >> _down \
| X##_f[_i+_skip+1] << _up; \
X##_f[_i++] = X##_f[3] >> _down; \
} \
for (; _i < 4; ++_i) \
X##_f[_i] = 0; \
} while (0)
/* Right shift with sticky-lsb.
* What this actually means is that we do a standard right-shift,
* but that if any of the bits that fall off the right hand side
* were one then we always set the LSbit.
*/
#define _FP_FRAC_SRS_4(X,N,size) \
do { \
_FP_I_TYPE _up, _down, _skip, _i; \
_FP_W_TYPE _s; \
_skip = (N) / _FP_W_TYPE_SIZE; \
_down = (N) % _FP_W_TYPE_SIZE; \
_up = _FP_W_TYPE_SIZE - _down; \
for (_s = _i = 0; _i < _skip; ++_i) \
_s |= X##_f[_i]; \
_s |= X##_f[_i] << _up; \
/* s is now != 0 if we want to set the LSbit */ \
if (!_down) \
for (_i = 0; _i <= 3-_skip; ++_i) \
X##_f[_i] = X##_f[_i+_skip]; \
else \
{ \
for (_i = 0; _i < 3-_skip; ++_i) \
X##_f[_i] = X##_f[_i+_skip] >> _down \
| X##_f[_i+_skip+1] << _up; \
X##_f[_i++] = X##_f[3] >> _down; \
} \
for (; _i < 4; ++_i) \
X##_f[_i] = 0; \
/* don't fix the LSB until the very end when we're sure f[0] is stable */ \
X##_f[0] |= (_s != 0); \
} while (0)
#define _FP_FRAC_ADD_4(R,X,Y) \
__FP_FRAC_ADD_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0], \
X##_f[3], X##_f[2], X##_f[1], X##_f[0], \
Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
#define _FP_FRAC_SUB_4(R,X,Y) \
__FP_FRAC_SUB_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0], \
X##_f[3], X##_f[2], X##_f[1], X##_f[0], \
Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
#define _FP_FRAC_DEC_4(X,Y) \
__FP_FRAC_DEC_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], \
Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
#define _FP_FRAC_ADDI_4(X,I) \
__FP_FRAC_ADDI_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], I)
#define _FP_ZEROFRAC_4 0,0,0,0
#define _FP_MINFRAC_4 0,0,0,1
#define _FP_MAXFRAC_4 (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0)
#define _FP_FRAC_ZEROP_4(X) ((X##_f[0] | X##_f[1] | X##_f[2] | X##_f[3]) == 0)
#define _FP_FRAC_NEGP_4(X) ((_FP_WS_TYPE)X##_f[3] < 0)
#define _FP_FRAC_OVERP_4(fs,X) (_FP_FRAC_HIGH_##fs(X) & _FP_OVERFLOW_##fs)
#define _FP_FRAC_EQ_4(X,Y) \
(X##_f[0] == Y##_f[0] && X##_f[1] == Y##_f[1] \
&& X##_f[2] == Y##_f[2] && X##_f[3] == Y##_f[3])
#define _FP_FRAC_GT_4(X,Y) \
(X##_f[3] > Y##_f[3] || \
(X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] || \
(X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] || \
(X##_f[1] == Y##_f[1] && X##_f[0] > Y##_f[0]) \
)) \
)) \
)
#define _FP_FRAC_GE_4(X,Y) \
(X##_f[3] > Y##_f[3] || \
(X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] || \
(X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] || \
(X##_f[1] == Y##_f[1] && X##_f[0] >= Y##_f[0]) \
)) \
)) \
)
#define _FP_FRAC_CLZ_4(R,X) \
do { \
if (X##_f[3]) \
{ \
__FP_CLZ(R,X##_f[3]); \
} \
else if (X##_f[2]) \
{ \
__FP_CLZ(R,X##_f[2]); \
R += _FP_W_TYPE_SIZE; \
} \
else if (X##_f[1]) \
{ \
__FP_CLZ(R,X##_f[2]); \
R += _FP_W_TYPE_SIZE*2; \
} \
else \
{ \
__FP_CLZ(R,X##_f[0]); \
R += _FP_W_TYPE_SIZE*3; \
} \
} while(0)
#define _FP_UNPACK_RAW_4(fs, X, val) \
do { \
union _FP_UNION_##fs _flo; _flo.flt = (val); \
X##_f[0] = _flo.bits.frac0; \
X##_f[1] = _flo.bits.frac1; \
X##_f[2] = _flo.bits.frac2; \
X##_f[3] = _flo.bits.frac3; \
X##_e = _flo.bits.exp; \
X##_s = _flo.bits.sign; \
} while (0)
#define _FP_UNPACK_RAW_4_P(fs, X, val) \
do { \
union _FP_UNION_##fs *_flo = \
(union _FP_UNION_##fs *)(val); \
\
X##_f[0] = _flo->bits.frac0; \
X##_f[1] = _flo->bits.frac1; \
X##_f[2] = _flo->bits.frac2; \
X##_f[3] = _flo->bits.frac3; \
X##_e = _flo->bits.exp; \
X##_s = _flo->bits.sign; \
} while (0)
#define _FP_PACK_RAW_4(fs, val, X) \
do { \
union _FP_UNION_##fs _flo; \
_flo.bits.frac0 = X##_f[0]; \
_flo.bits.frac1 = X##_f[1]; \
_flo.bits.frac2 = X##_f[2]; \
_flo.bits.frac3 = X##_f[3]; \
_flo.bits.exp = X##_e; \
_flo.bits.sign = X##_s; \
(val) = _flo.flt; \
} while (0)
#define _FP_PACK_RAW_4_P(fs, val, X) \
do { \
union _FP_UNION_##fs *_flo = \
(union _FP_UNION_##fs *)(val); \
\
_flo->bits.frac0 = X##_f[0]; \
_flo->bits.frac1 = X##_f[1]; \
_flo->bits.frac2 = X##_f[2]; \
_flo->bits.frac3 = X##_f[3]; \
_flo->bits.exp = X##_e; \
_flo->bits.sign = X##_s; \
} while (0)
/*
* Multiplication algorithms:
*/
/* Given a 1W * 1W => 2W primitive, do the extended multiplication. */
#define _FP_MUL_MEAT_4_wide(wfracbits, R, X, Y, doit) \
do { \
_FP_FRAC_DECL_8(_z); _FP_FRAC_DECL_2(_b); _FP_FRAC_DECL_2(_c); \
_FP_FRAC_DECL_2(_d); _FP_FRAC_DECL_2(_e); _FP_FRAC_DECL_2(_f); \
\
doit(_FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0), X##_f[0], Y##_f[0]); \
doit(_b_f1, _b_f0, X##_f[0], Y##_f[1]); \
doit(_c_f1, _c_f0, X##_f[1], Y##_f[0]); \
doit(_d_f1, _d_f0, X##_f[1], Y##_f[1]); \
doit(_e_f1, _e_f0, X##_f[0], Y##_f[2]); \
doit(_f_f1, _f_f0, X##_f[2], Y##_f[0]); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \
_FP_FRAC_WORD_8(_z,1), 0,_b_f1,_b_f0, \
0,0,_FP_FRAC_WORD_8(_z,1)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \
_FP_FRAC_WORD_8(_z,1), 0,_c_f1,_c_f0, \
_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2), \
_FP_FRAC_WORD_8(_z,1)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \
_FP_FRAC_WORD_8(_z,2), 0,_d_f1,_d_f0, \
0,_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \
_FP_FRAC_WORD_8(_z,2), 0,_e_f1,_e_f0, \
_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \
_FP_FRAC_WORD_8(_z,2)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \
_FP_FRAC_WORD_8(_z,2), 0,_f_f1,_f_f0, \
_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3), \
_FP_FRAC_WORD_8(_z,2)); \
doit(_b_f1, _b_f0, X##_f[0], Y##_f[3]); \
doit(_c_f1, _c_f0, X##_f[3], Y##_f[0]); \
doit(_d_f1, _d_f0, X##_f[1], Y##_f[2]); \
doit(_e_f1, _e_f0, X##_f[2], Y##_f[1]); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3), 0,_b_f1,_b_f0, \
0,_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3), 0,_c_f1,_c_f0, \
_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3), 0,_d_f1,_d_f0, \
_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3), 0,_e_f1,_e_f0, \
_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4), \
_FP_FRAC_WORD_8(_z,3)); \
doit(_b_f1, _b_f0, X##_f[2], Y##_f[2]); \
doit(_c_f1, _c_f0, X##_f[1], Y##_f[3]); \
doit(_d_f1, _d_f0, X##_f[3], Y##_f[1]); \
doit(_e_f1, _e_f0, X##_f[2], Y##_f[3]); \
doit(_f_f1, _f_f0, X##_f[3], Y##_f[2]); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \
_FP_FRAC_WORD_8(_z,4), 0,_b_f1,_b_f0, \
0,_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \
_FP_FRAC_WORD_8(_z,4), 0,_c_f1,_c_f0, \
_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \
_FP_FRAC_WORD_8(_z,4)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \
_FP_FRAC_WORD_8(_z,4), 0,_d_f1,_d_f0, \
_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5), \
_FP_FRAC_WORD_8(_z,4)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \
_FP_FRAC_WORD_8(_z,5), 0,_e_f1,_e_f0, \
0,_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \
_FP_FRAC_WORD_8(_z,5), 0,_f_f1,_f_f0, \
_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \
_FP_FRAC_WORD_8(_z,5)); \
doit(_b_f1, _b_f0, X##_f[3], Y##_f[3]); \
__FP_FRAC_ADD_2(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6), \
_b_f1,_b_f0, \
_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6)); \
\
/* Normalize since we know where the msb of the multiplicands \
were (bit B), we know that the msb of the of the product is \
at either 2B or 2B-1. */ \
_FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits); \
__FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2), \
_FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0)); \
} while (0)
#define _FP_MUL_MEAT_4_gmp(wfracbits, R, X, Y) \
do { \
_FP_FRAC_DECL_8(_z); \
\
mpn_mul_n(_z_f, _x_f, _y_f, 4); \
\
/* Normalize since we know where the msb of the multiplicands \
were (bit B), we know that the msb of the of the product is \
at either 2B or 2B-1. */ \
_FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits); \
__FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2), \
_FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0)); \
} while (0)
/*
* Helper utility for _FP_DIV_MEAT_4_udiv:
* pppp = m * nnn
*/
#define umul_ppppmnnn(p3,p2,p1,p0,m,n2,n1,n0) \
do { \
UWtype _t; \
umul_ppmm(p1,p0,m,n0); \
umul_ppmm(p2,_t,m,n1); \
__FP_FRAC_ADDI_2(p2,p1,_t); \
umul_ppmm(p3,_t,m,n2); \
__FP_FRAC_ADDI_2(p3,p2,_t); \
} while (0)
/*
* Division algorithms:
*/
#define _FP_DIV_MEAT_4_udiv(fs, R, X, Y) \
do { \
int _i; \
_FP_FRAC_DECL_4(_n); _FP_FRAC_DECL_4(_m); \
_FP_FRAC_SET_4(_n, _FP_ZEROFRAC_4); \
if (_FP_FRAC_GT_4(X, Y)) \
{ \
_n_f[3] = X##_f[0] << (_FP_W_TYPE_SIZE - 1); \
_FP_FRAC_SRL_4(X, 1); \
} \
else \
R##_e--; \
\
/* Normalize, i.e. make the most significant bit of the \
denominator set. */ \
_FP_FRAC_SLL_4(Y, _FP_WFRACXBITS_##fs); \
\
for (_i = 3; ; _i--) \
{ \
if (X##_f[3] == Y##_f[3]) \
{ \
/* This is a special case, not an optimization \
(X##_f[3]/Y##_f[3] would not fit into UWtype). \
As X## is guaranteed to be < Y, R##_f[_i] can be either \
(UWtype)-1 or (UWtype)-2. */ \
R##_f[_i] = -1; \
if (!_i) \
break; \
__FP_FRAC_SUB_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], \
Y##_f[2], Y##_f[1], Y##_f[0], 0, \
X##_f[2], X##_f[1], X##_f[0], _n_f[_i]); \
_FP_FRAC_SUB_4(X, Y, X); \
if (X##_f[3] > Y##_f[3]) \
{ \
R##_f[_i] = -2; \
_FP_FRAC_ADD_4(X, Y, X); \
} \
} \
else \
{ \
udiv_qrnnd(R##_f[_i], X##_f[3], X##_f[3], X##_f[2], Y##_f[3]); \
umul_ppppmnnn(_m_f[3], _m_f[2], _m_f[1], _m_f[0], \
R##_f[_i], Y##_f[2], Y##_f[1], Y##_f[0]); \
X##_f[2] = X##_f[1]; \
X##_f[1] = X##_f[0]; \
X##_f[0] = _n_f[_i]; \
if (_FP_FRAC_GT_4(_m, X)) \
{ \
R##_f[_i]--; \
_FP_FRAC_ADD_4(X, Y, X); \
if (_FP_FRAC_GE_4(X, Y) && _FP_FRAC_GT_4(_m, X)) \
{ \
R##_f[_i]--; \
_FP_FRAC_ADD_4(X, Y, X); \
} \
} \
_FP_FRAC_DEC_4(X, _m); \
if (!_i) \
{ \
if (!_FP_FRAC_EQ_4(X, _m)) \
R##_f[0] |= _FP_WORK_STICKY; \
break; \
} \
} \
} \
} while (0)
/*
* Square root algorithms:
* We have just one right now, maybe Newton approximation
* should be added for those machines where division is fast.
*/
#define _FP_SQRT_MEAT_4(R, S, T, X, q) \
do { \
while (q) \
{ \
T##_f[3] = S##_f[3] + q; \
if (T##_f[3] <= X##_f[3]) \
{ \
S##_f[3] = T##_f[3] + q; \
X##_f[3] -= T##_f[3]; \
R##_f[3] += q; \
} \
_FP_FRAC_SLL_4(X, 1); \
q >>= 1; \
} \
q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \
while (q) \
{ \
T##_f[2] = S##_f[2] + q; \
T##_f[3] = S##_f[3]; \
if (T##_f[3] < X##_f[3] || \
(T##_f[3] == X##_f[3] && T##_f[2] <= X##_f[2])) \
{ \
S##_f[2] = T##_f[2] + q; \
S##_f[3] += (T##_f[2] > S##_f[2]); \
__FP_FRAC_DEC_2(X##_f[3], X##_f[2], \
T##_f[3], T##_f[2]); \
R##_f[2] += q; \
} \
_FP_FRAC_SLL_4(X, 1); \
q >>= 1; \
} \
q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \
while (q) \
{ \
T##_f[1] = S##_f[1] + q; \
T##_f[2] = S##_f[2]; \
T##_f[3] = S##_f[3]; \
if (T##_f[3] < X##_f[3] || \
(T##_f[3] == X##_f[3] && (T##_f[2] < X##_f[2] || \
(T##_f[2] == X##_f[2] && T##_f[1] <= X##_f[1])))) \
{ \
S##_f[1] = T##_f[1] + q; \
S##_f[2] += (T##_f[1] > S##_f[1]); \
S##_f[3] += (T##_f[2] > S##_f[2]); \
__FP_FRAC_DEC_3(X##_f[3], X##_f[2], X##_f[1], \
T##_f[3], T##_f[2], T##_f[1]); \
R##_f[1] += q; \
} \
_FP_FRAC_SLL_4(X, 1); \
q >>= 1; \
} \
q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \
while (q != _FP_WORK_ROUND) \
{ \
T##_f[0] = S##_f[0] + q; \
T##_f[1] = S##_f[1]; \
T##_f[2] = S##_f[2]; \
T##_f[3] = S##_f[3]; \
if (_FP_FRAC_GE_4(X,T)) \
{ \
S##_f[0] = T##_f[0] + q; \
S##_f[1] += (T##_f[0] > S##_f[0]); \
S##_f[2] += (T##_f[1] > S##_f[1]); \
S##_f[3] += (T##_f[2] > S##_f[2]); \
_FP_FRAC_DEC_4(X, T); \
R##_f[0] += q; \
} \
_FP_FRAC_SLL_4(X, 1); \
q >>= 1; \
} \
if (!_FP_FRAC_ZEROP_4(X)) \
{ \
if (_FP_FRAC_GT_4(X,S)) \
R##_f[0] |= _FP_WORK_ROUND; \
R##_f[0] |= _FP_WORK_STICKY; \
} \
} while (0)
/*
* Internals
*/
#define __FP_FRAC_SET_4(X,I3,I2,I1,I0) \
(X##_f[3] = I3, X##_f[2] = I2, X##_f[1] = I1, X##_f[0] = I0)
#ifndef __FP_FRAC_ADD_3
#define __FP_FRAC_ADD_3(r2,r1,r0,x2,x1,x0,y2,y1,y0) \
(r0 = x0 + y0, \
r1 = x1 + y1 + (r0 < x0), \
r2 = x2 + y2 + (r1 < x1))
#endif
#ifndef __FP_FRAC_ADD_4
#define __FP_FRAC_ADD_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0) \
(r0 = x0 + y0, \
r1 = x1 + y1 + (r0 < x0), \
r2 = x2 + y2 + (r1 < x1), \
r3 = x3 + y3 + (r2 < x2))
#endif
#ifndef __FP_FRAC_SUB_3
#define __FP_FRAC_SUB_3(r2,r1,r0,x2,x1,x0,y2,y1,y0) \
(r0 = x0 - y0, \
r1 = x1 - y1 - (r0 > x0), \
r2 = x2 - y2 - (r1 > x1))
#endif
#ifndef __FP_FRAC_SUB_4
#define __FP_FRAC_SUB_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0) \
(r0 = x0 - y0, \
r1 = x1 - y1 - (r0 > x0), \
r2 = x2 - y2 - (r1 > x1), \
r3 = x3 - y3 - (r2 > x2))
#endif
#ifndef __FP_FRAC_DEC_3
#define __FP_FRAC_DEC_3(x2,x1,x0,y2,y1,y0) \
do { \
UWtype _t0, _t1; \
_t0 = x0; \
x0 -= y0; \
_t1 = x1; \
x1 -= y1 + (x0 > _t0); \
x2 -= y2 + (x1 > _t1); \
} while (0)
#endif
#ifndef __FP_FRAC_DEC_4
#define __FP_FRAC_DEC_4(x3,x2,x1,x0,y3,y2,y1,y0) \
do { \
UWtype _t0, _t1; \
_t0 = x0; \
x0 -= y0; \
_t1 = x1; \
x1 -= y1 + (x0 > _t0); \
_t0 = x2; \
x2 -= y2 + (x1 > _t1); \
x3 -= y3 + (x2 > _t0); \
} while (0)
#endif
#ifndef __FP_FRAC_ADDI_4
#define __FP_FRAC_ADDI_4(x3,x2,x1,x0,i) \
do { \
UWtype _t; \
_t = ((x0 += i) < i); \
x1 += _t; _t = (x1 < _t); \
x2 += _t; _t = (x2 < _t); \
x3 += _t; \
} while (0)
#endif
/* Convert FP values between word sizes. This appears to be more
* complicated than I'd have expected it to be, so these might be
* wrong... These macros are in any case somewhat bogus because they
* use information about what various FRAC_n variables look like
* internally [eg, that 2 word vars are X_f0 and x_f1]. But so do
* the ones in op-2.h and op-1.h.
*/
#define _FP_FRAC_CONV_1_4(dfs, sfs, D, S) \
do { \
if (S##_c != FP_CLS_NAN) \
_FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs), \
_FP_WFRACBITS_##sfs); \
else \
_FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs)); \
D##_f = S##_f[0]; \
} while (0)
#define _FP_FRAC_CONV_2_4(dfs, sfs, D, S) \
do { \
if (S##_c != FP_CLS_NAN) \
_FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs), \
_FP_WFRACBITS_##sfs); \
else \
_FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs)); \
D##_f0 = S##_f[0]; \
D##_f1 = S##_f[1]; \
} while (0)
/* Assembly/disassembly for converting to/from integral types.
* No shifting or overflow handled here.
*/
/* Put the FP value X into r, which is an integer of size rsize. */
#define _FP_FRAC_ASSEMBLE_4(r, X, rsize) \
do { \
if (rsize <= _FP_W_TYPE_SIZE) \
r = X##_f[0]; \
else if (rsize <= 2*_FP_W_TYPE_SIZE) \
{ \
r = X##_f[1]; \
r <<= _FP_W_TYPE_SIZE; \
r += X##_f[0]; \
} \
else \
{ \
/* I'm feeling lazy so we deal with int == 3words (implausible)*/ \
/* and int == 4words as a single case. */ \
r = X##_f[3]; \
r <<= _FP_W_TYPE_SIZE; \
r += X##_f[2]; \
r <<= _FP_W_TYPE_SIZE; \
r += X##_f[1]; \
r <<= _FP_W_TYPE_SIZE; \
r += X##_f[0]; \
} \
} while (0)
/* "No disassemble Number Five!" */
/* move an integer of size rsize into X's fractional part. We rely on
* the _f[] array consisting of words of size _FP_W_TYPE_SIZE to avoid
* having to mask the values we store into it.
*/
#define _FP_FRAC_DISASSEMBLE_4(X, r, rsize) \
do { \
X##_f[0] = r; \
X##_f[1] = (rsize <= _FP_W_TYPE_SIZE ? 0 : r >> _FP_W_TYPE_SIZE); \
X##_f[2] = (rsize <= 2*_FP_W_TYPE_SIZE ? 0 : r >> 2*_FP_W_TYPE_SIZE); \
X##_f[3] = (rsize <= 3*_FP_W_TYPE_SIZE ? 0 : r >> 3*_FP_W_TYPE_SIZE); \
} while (0);
#define _FP_FRAC_CONV_4_1(dfs, sfs, D, S) \
do { \
D##_f[0] = S##_f; \
D##_f[1] = D##_f[2] = D##_f[3] = 0; \
_FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs)); \
} while (0)
#define _FP_FRAC_CONV_4_2(dfs, sfs, D, S) \
do { \
D##_f[0] = S##_f0; \
D##_f[1] = S##_f1; \
D##_f[2] = D##_f[3] = 0; \
_FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs)); \
} while (0)
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