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linux/include/math-emu/op-2.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2 
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

614 lines
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C
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/* Software floating-point emulation.
Basic two-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. */
#ifndef __MATH_EMU_OP_2_H__
#define __MATH_EMU_OP_2_H__
#define _FP_FRAC_DECL_2(X) _FP_W_TYPE X##_f0, X##_f1
#define _FP_FRAC_COPY_2(D,S) (D##_f0 = S##_f0, D##_f1 = S##_f1)
#define _FP_FRAC_SET_2(X,I) __FP_FRAC_SET_2(X, I)
#define _FP_FRAC_HIGH_2(X) (X##_f1)
#define _FP_FRAC_LOW_2(X) (X##_f0)
#define _FP_FRAC_WORD_2(X,w) (X##_f##w)
#define _FP_FRAC_SLL_2(X,N) \
do { \
if ((N) < _FP_W_TYPE_SIZE) \
{ \
if (__builtin_constant_p(N) && (N) == 1) \
{ \
X##_f1 = X##_f1 + X##_f1 + (((_FP_WS_TYPE)(X##_f0)) < 0); \
X##_f0 += X##_f0; \
} \
else \
{ \
X##_f1 = X##_f1 << (N) | X##_f0 >> (_FP_W_TYPE_SIZE - (N)); \
X##_f0 <<= (N); \
} \
} \
else \
{ \
X##_f1 = X##_f0 << ((N) - _FP_W_TYPE_SIZE); \
X##_f0 = 0; \
} \
} while (0)
#define _FP_FRAC_SRL_2(X,N) \
do { \
if ((N) < _FP_W_TYPE_SIZE) \
{ \
X##_f0 = X##_f0 >> (N) | X##_f1 << (_FP_W_TYPE_SIZE - (N)); \
X##_f1 >>= (N); \
} \
else \
{ \
X##_f0 = X##_f1 >> ((N) - _FP_W_TYPE_SIZE); \
X##_f1 = 0; \
} \
} while (0)
/* Right shift with sticky-lsb. */
#define _FP_FRAC_SRS_2(X,N,sz) \
do { \
if ((N) < _FP_W_TYPE_SIZE) \
{ \
X##_f0 = (X##_f1 << (_FP_W_TYPE_SIZE - (N)) | X##_f0 >> (N) | \
(__builtin_constant_p(N) && (N) == 1 \
? X##_f0 & 1 \
: (X##_f0 << (_FP_W_TYPE_SIZE - (N))) != 0)); \
X##_f1 >>= (N); \
} \
else \
{ \
X##_f0 = (X##_f1 >> ((N) - _FP_W_TYPE_SIZE) | \
(((X##_f1 << (2*_FP_W_TYPE_SIZE - (N))) | X##_f0) != 0)); \
X##_f1 = 0; \
} \
} while (0)
#define _FP_FRAC_ADDI_2(X,I) \
__FP_FRAC_ADDI_2(X##_f1, X##_f0, I)
#define _FP_FRAC_ADD_2(R,X,Y) \
__FP_FRAC_ADD_2(R##_f1, R##_f0, X##_f1, X##_f0, Y##_f1, Y##_f0)
#define _FP_FRAC_SUB_2(R,X,Y) \
__FP_FRAC_SUB_2(R##_f1, R##_f0, X##_f1, X##_f0, Y##_f1, Y##_f0)
#define _FP_FRAC_DEC_2(X,Y) \
__FP_FRAC_DEC_2(X##_f1, X##_f0, Y##_f1, Y##_f0)
#define _FP_FRAC_CLZ_2(R,X) \
do { \
if (X##_f1) \
__FP_CLZ(R,X##_f1); \
else \
{ \
__FP_CLZ(R,X##_f0); \
R += _FP_W_TYPE_SIZE; \
} \
} while(0)
/* Predicates */
#define _FP_FRAC_NEGP_2(X) ((_FP_WS_TYPE)X##_f1 < 0)
#define _FP_FRAC_ZEROP_2(X) ((X##_f1 | X##_f0) == 0)
#define _FP_FRAC_OVERP_2(fs,X) (_FP_FRAC_HIGH_##fs(X) & _FP_OVERFLOW_##fs)
#define _FP_FRAC_CLEAR_OVERP_2(fs,X) (_FP_FRAC_HIGH_##fs(X) &= ~_FP_OVERFLOW_##fs)
#define _FP_FRAC_EQ_2(X, Y) (X##_f1 == Y##_f1 && X##_f0 == Y##_f0)
#define _FP_FRAC_GT_2(X, Y) \
(X##_f1 > Y##_f1 || (X##_f1 == Y##_f1 && X##_f0 > Y##_f0))
#define _FP_FRAC_GE_2(X, Y) \
(X##_f1 > Y##_f1 || (X##_f1 == Y##_f1 && X##_f0 >= Y##_f0))
#define _FP_ZEROFRAC_2 0, 0
#define _FP_MINFRAC_2 0, 1
#define _FP_MAXFRAC_2 (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0)
/*
* Internals
*/
#define __FP_FRAC_SET_2(X,I1,I0) (X##_f0 = I0, X##_f1 = I1)
#define __FP_CLZ_2(R, xh, xl) \
do { \
if (xh) \
__FP_CLZ(R,xh); \
else \
{ \
__FP_CLZ(R,xl); \
R += _FP_W_TYPE_SIZE; \
} \
} while(0)
#if 0
#ifndef __FP_FRAC_ADDI_2
#define __FP_FRAC_ADDI_2(xh, xl, i) \
(xh += ((xl += i) < i))
#endif
#ifndef __FP_FRAC_ADD_2
#define __FP_FRAC_ADD_2(rh, rl, xh, xl, yh, yl) \
(rh = xh + yh + ((rl = xl + yl) < xl))
#endif
#ifndef __FP_FRAC_SUB_2
#define __FP_FRAC_SUB_2(rh, rl, xh, xl, yh, yl) \
(rh = xh - yh - ((rl = xl - yl) > xl))
#endif
#ifndef __FP_FRAC_DEC_2
#define __FP_FRAC_DEC_2(xh, xl, yh, yl) \
do { \
UWtype _t = xl; \
xh -= yh + ((xl -= yl) > _t); \
} while (0)
#endif
#else
#undef __FP_FRAC_ADDI_2
#define __FP_FRAC_ADDI_2(xh, xl, i) add_ssaaaa(xh, xl, xh, xl, 0, i)
#undef __FP_FRAC_ADD_2
#define __FP_FRAC_ADD_2 add_ssaaaa
#undef __FP_FRAC_SUB_2
#define __FP_FRAC_SUB_2 sub_ddmmss
#undef __FP_FRAC_DEC_2
#define __FP_FRAC_DEC_2(xh, xl, yh, yl) sub_ddmmss(xh, xl, xh, xl, yh, yl)
#endif
/*
* Unpack the raw bits of a native fp value. Do not classify or
* normalize the data.
*/
#define _FP_UNPACK_RAW_2(fs, X, val) \
do { \
union _FP_UNION_##fs _flo; _flo.flt = (val); \
\
X##_f0 = _flo.bits.frac0; \
X##_f1 = _flo.bits.frac1; \
X##_e = _flo.bits.exp; \
X##_s = _flo.bits.sign; \
} while (0)
#define _FP_UNPACK_RAW_2_P(fs, X, val) \
do { \
union _FP_UNION_##fs *_flo = \
(union _FP_UNION_##fs *)(val); \
\
X##_f0 = _flo->bits.frac0; \
X##_f1 = _flo->bits.frac1; \
X##_e = _flo->bits.exp; \
X##_s = _flo->bits.sign; \
} while (0)
/*
* Repack the raw bits of a native fp value.
*/
#define _FP_PACK_RAW_2(fs, val, X) \
do { \
union _FP_UNION_##fs _flo; \
\
_flo.bits.frac0 = X##_f0; \
_flo.bits.frac1 = X##_f1; \
_flo.bits.exp = X##_e; \
_flo.bits.sign = X##_s; \
\
(val) = _flo.flt; \
} while (0)
#define _FP_PACK_RAW_2_P(fs, val, X) \
do { \
union _FP_UNION_##fs *_flo = \
(union _FP_UNION_##fs *)(val); \
\
_flo->bits.frac0 = X##_f0; \
_flo->bits.frac1 = X##_f1; \
_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_2_wide(wfracbits, R, X, Y, doit) \
do { \
_FP_FRAC_DECL_4(_z); _FP_FRAC_DECL_2(_b); _FP_FRAC_DECL_2(_c); \
\
doit(_FP_FRAC_WORD_4(_z,1), _FP_FRAC_WORD_4(_z,0), X##_f0, Y##_f0); \
doit(_b_f1, _b_f0, X##_f0, Y##_f1); \
doit(_c_f1, _c_f0, X##_f1, Y##_f0); \
doit(_FP_FRAC_WORD_4(_z,3), _FP_FRAC_WORD_4(_z,2), X##_f1, Y##_f1); \
\
__FP_FRAC_ADD_3(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1), 0, _b_f1, _b_f0, \
_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1)); \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1), 0, _c_f1, _c_f0, \
_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1)); \
\
/* 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_4(_z, wfracbits-1, 2*wfracbits); \
R##_f0 = _FP_FRAC_WORD_4(_z,0); \
R##_f1 = _FP_FRAC_WORD_4(_z,1); \
} while (0)
/* Given a 1W * 1W => 2W primitive, do the extended multiplication.
Do only 3 multiplications instead of four. This one is for machines
where multiplication is much more expensive than subtraction. */
#define _FP_MUL_MEAT_2_wide_3mul(wfracbits, R, X, Y, doit) \
do { \
_FP_FRAC_DECL_4(_z); _FP_FRAC_DECL_2(_b); _FP_FRAC_DECL_2(_c); \
_FP_W_TYPE _d; \
int _c1, _c2; \
\
_b_f0 = X##_f0 + X##_f1; \
_c1 = _b_f0 < X##_f0; \
_b_f1 = Y##_f0 + Y##_f1; \
_c2 = _b_f1 < Y##_f0; \
doit(_d, _FP_FRAC_WORD_4(_z,0), X##_f0, Y##_f0); \
doit(_FP_FRAC_WORD_4(_z,2), _FP_FRAC_WORD_4(_z,1), _b_f0, _b_f1); \
doit(_c_f1, _c_f0, X##_f1, Y##_f1); \
\
_b_f0 &= -_c2; \
_b_f1 &= -_c1; \
__FP_FRAC_ADD_3(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1), (_c1 & _c2), 0, _d, \
0, _FP_FRAC_WORD_4(_z,2), _FP_FRAC_WORD_4(_z,1)); \
__FP_FRAC_ADDI_2(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_b_f0); \
__FP_FRAC_ADDI_2(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_b_f1); \
__FP_FRAC_DEC_3(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1), \
0, _d, _FP_FRAC_WORD_4(_z,0)); \
__FP_FRAC_DEC_3(_FP_FRAC_WORD_4(_z,3),_FP_FRAC_WORD_4(_z,2), \
_FP_FRAC_WORD_4(_z,1), 0, _c_f1, _c_f0); \
__FP_FRAC_ADD_2(_FP_FRAC_WORD_4(_z,3), _FP_FRAC_WORD_4(_z,2), \
_c_f1, _c_f0, \
_FP_FRAC_WORD_4(_z,3), _FP_FRAC_WORD_4(_z,2)); \
\
/* 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_4(_z, wfracbits-1, 2*wfracbits); \
R##_f0 = _FP_FRAC_WORD_4(_z,0); \
R##_f1 = _FP_FRAC_WORD_4(_z,1); \
} while (0)
#define _FP_MUL_MEAT_2_gmp(wfracbits, R, X, Y) \
do { \
_FP_FRAC_DECL_4(_z); \
_FP_W_TYPE _x[2], _y[2]; \
_x[0] = X##_f0; _x[1] = X##_f1; \
_y[0] = Y##_f0; _y[1] = Y##_f1; \
\
mpn_mul_n(_z_f, _x, _y, 2); \
\
/* 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_4(_z, wfracbits-1, 2*wfracbits); \
R##_f0 = _z_f[0]; \
R##_f1 = _z_f[1]; \
} while (0)
/* Do at most 120x120=240 bits multiplication using double floating
point multiplication. This is useful if floating point
multiplication has much bigger throughput than integer multiply.
It is supposed to work for _FP_W_TYPE_SIZE 64 and wfracbits
between 106 and 120 only.
Caller guarantees that X and Y has (1LLL << (wfracbits - 1)) set.
SETFETZ is a macro which will disable all FPU exceptions and set rounding
towards zero, RESETFE should optionally reset it back. */
#define _FP_MUL_MEAT_2_120_240_double(wfracbits, R, X, Y, setfetz, resetfe) \
do { \
static const double _const[] = { \
/* 2^-24 */ 5.9604644775390625e-08, \
/* 2^-48 */ 3.5527136788005009e-15, \
/* 2^-72 */ 2.1175823681357508e-22, \
/* 2^-96 */ 1.2621774483536189e-29, \
/* 2^28 */ 2.68435456e+08, \
/* 2^4 */ 1.600000e+01, \
/* 2^-20 */ 9.5367431640625e-07, \
/* 2^-44 */ 5.6843418860808015e-14, \
/* 2^-68 */ 3.3881317890172014e-21, \
/* 2^-92 */ 2.0194839173657902e-28, \
/* 2^-116 */ 1.2037062152420224e-35}; \
double _a240, _b240, _c240, _d240, _e240, _f240, \
_g240, _h240, _i240, _j240, _k240; \
union { double d; UDItype i; } _l240, _m240, _n240, _o240, \
_p240, _q240, _r240, _s240; \
UDItype _t240, _u240, _v240, _w240, _x240, _y240 = 0; \
\
if (wfracbits < 106 || wfracbits > 120) \
abort(); \
\
setfetz; \
\
_e240 = (double)(long)(X##_f0 & 0xffffff); \
_j240 = (double)(long)(Y##_f0 & 0xffffff); \
_d240 = (double)(long)((X##_f0 >> 24) & 0xffffff); \
_i240 = (double)(long)((Y##_f0 >> 24) & 0xffffff); \
_c240 = (double)(long)(((X##_f1 << 16) & 0xffffff) | (X##_f0 >> 48)); \
_h240 = (double)(long)(((Y##_f1 << 16) & 0xffffff) | (Y##_f0 >> 48)); \
_b240 = (double)(long)((X##_f1 >> 8) & 0xffffff); \
_g240 = (double)(long)((Y##_f1 >> 8) & 0xffffff); \
_a240 = (double)(long)(X##_f1 >> 32); \
_f240 = (double)(long)(Y##_f1 >> 32); \
_e240 *= _const[3]; \
_j240 *= _const[3]; \
_d240 *= _const[2]; \
_i240 *= _const[2]; \
_c240 *= _const[1]; \
_h240 *= _const[1]; \
_b240 *= _const[0]; \
_g240 *= _const[0]; \
_s240.d = _e240*_j240;\
_r240.d = _d240*_j240 + _e240*_i240;\
_q240.d = _c240*_j240 + _d240*_i240 + _e240*_h240;\
_p240.d = _b240*_j240 + _c240*_i240 + _d240*_h240 + _e240*_g240;\
_o240.d = _a240*_j240 + _b240*_i240 + _c240*_h240 + _d240*_g240 + _e240*_f240;\
_n240.d = _a240*_i240 + _b240*_h240 + _c240*_g240 + _d240*_f240; \
_m240.d = _a240*_h240 + _b240*_g240 + _c240*_f240; \
_l240.d = _a240*_g240 + _b240*_f240; \
_k240 = _a240*_f240; \
_r240.d += _s240.d; \
_q240.d += _r240.d; \
_p240.d += _q240.d; \
_o240.d += _p240.d; \
_n240.d += _o240.d; \
_m240.d += _n240.d; \
_l240.d += _m240.d; \
_k240 += _l240.d; \
_s240.d -= ((_const[10]+_s240.d)-_const[10]); \
_r240.d -= ((_const[9]+_r240.d)-_const[9]); \
_q240.d -= ((_const[8]+_q240.d)-_const[8]); \
_p240.d -= ((_const[7]+_p240.d)-_const[7]); \
_o240.d += _const[7]; \
_n240.d += _const[6]; \
_m240.d += _const[5]; \
_l240.d += _const[4]; \
if (_s240.d != 0.0) _y240 = 1; \
if (_r240.d != 0.0) _y240 = 1; \
if (_q240.d != 0.0) _y240 = 1; \
if (_p240.d != 0.0) _y240 = 1; \
_t240 = (DItype)_k240; \
_u240 = _l240.i; \
_v240 = _m240.i; \
_w240 = _n240.i; \
_x240 = _o240.i; \
R##_f1 = (_t240 << (128 - (wfracbits - 1))) \
| ((_u240 & 0xffffff) >> ((wfracbits - 1) - 104)); \
R##_f0 = ((_u240 & 0xffffff) << (168 - (wfracbits - 1))) \
| ((_v240 & 0xffffff) << (144 - (wfracbits - 1))) \
| ((_w240 & 0xffffff) << (120 - (wfracbits - 1))) \
| ((_x240 & 0xffffff) >> ((wfracbits - 1) - 96)) \
| _y240; \
resetfe; \
} while (0)
/*
* Division algorithms:
*/
#define _FP_DIV_MEAT_2_udiv(fs, R, X, Y) \
do { \
_FP_W_TYPE _n_f2, _n_f1, _n_f0, _r_f1, _r_f0, _m_f1, _m_f0; \
if (_FP_FRAC_GT_2(X, Y)) \
{ \
_n_f2 = X##_f1 >> 1; \
_n_f1 = X##_f1 << (_FP_W_TYPE_SIZE - 1) | X##_f0 >> 1; \
_n_f0 = X##_f0 << (_FP_W_TYPE_SIZE - 1); \
} \
else \
{ \
R##_e--; \
_n_f2 = X##_f1; \
_n_f1 = X##_f0; \
_n_f0 = 0; \
} \
\
/* Normalize, i.e. make the most significant bit of the \
denominator set. */ \
_FP_FRAC_SLL_2(Y, _FP_WFRACXBITS_##fs); \
\
udiv_qrnnd(R##_f1, _r_f1, _n_f2, _n_f1, Y##_f1); \
umul_ppmm(_m_f1, _m_f0, R##_f1, Y##_f0); \
_r_f0 = _n_f0; \
if (_FP_FRAC_GT_2(_m, _r)) \
{ \
R##_f1--; \
_FP_FRAC_ADD_2(_r, Y, _r); \
if (_FP_FRAC_GE_2(_r, Y) && _FP_FRAC_GT_2(_m, _r)) \
{ \
R##_f1--; \
_FP_FRAC_ADD_2(_r, Y, _r); \
} \
} \
_FP_FRAC_DEC_2(_r, _m); \
\
if (_r_f1 == Y##_f1) \
{ \
/* This is a special case, not an optimization \
(_r/Y##_f1 would not fit into UWtype). \
As _r is guaranteed to be < Y, R##_f0 can be either \
(UWtype)-1 or (UWtype)-2. But as we know what kind \
of bits it is (sticky, guard, round), we don't care. \
We also don't care what the reminder is, because the \
guard bit will be set anyway. -jj */ \
R##_f0 = -1; \
} \
else \
{ \
udiv_qrnnd(R##_f0, _r_f1, _r_f1, _r_f0, Y##_f1); \
umul_ppmm(_m_f1, _m_f0, R##_f0, Y##_f0); \
_r_f0 = 0; \
if (_FP_FRAC_GT_2(_m, _r)) \
{ \
R##_f0--; \
_FP_FRAC_ADD_2(_r, Y, _r); \
if (_FP_FRAC_GE_2(_r, Y) && _FP_FRAC_GT_2(_m, _r)) \
{ \
R##_f0--; \
_FP_FRAC_ADD_2(_r, Y, _r); \
} \
} \
if (!_FP_FRAC_EQ_2(_r, _m)) \
R##_f0 |= _FP_WORK_STICKY; \
} \
} while (0)
#define _FP_DIV_MEAT_2_gmp(fs, R, X, Y) \
do { \
_FP_W_TYPE _x[4], _y[2], _z[4]; \
_y[0] = Y##_f0; _y[1] = Y##_f1; \
_x[0] = _x[3] = 0; \
if (_FP_FRAC_GT_2(X, Y)) \
{ \
R##_e++; \
_x[1] = (X##_f0 << (_FP_WFRACBITS_##fs-1 - _FP_W_TYPE_SIZE) | \
X##_f1 >> (_FP_W_TYPE_SIZE - \
(_FP_WFRACBITS_##fs-1 - _FP_W_TYPE_SIZE))); \
_x[2] = X##_f1 << (_FP_WFRACBITS_##fs-1 - _FP_W_TYPE_SIZE); \
} \
else \
{ \
_x[1] = (X##_f0 << (_FP_WFRACBITS_##fs - _FP_W_TYPE_SIZE) | \
X##_f1 >> (_FP_W_TYPE_SIZE - \
(_FP_WFRACBITS_##fs - _FP_W_TYPE_SIZE))); \
_x[2] = X##_f1 << (_FP_WFRACBITS_##fs - _FP_W_TYPE_SIZE); \
} \
\
(void) mpn_divrem (_z, 0, _x, 4, _y, 2); \
R##_f1 = _z[1]; \
R##_f0 = _z[0] | ((_x[0] | _x[1]) != 0); \
} 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_2(R, S, T, X, q) \
do { \
while (q) \
{ \
T##_f1 = S##_f1 + q; \
if (T##_f1 <= X##_f1) \
{ \
S##_f1 = T##_f1 + q; \
X##_f1 -= T##_f1; \
R##_f1 += q; \
} \
_FP_FRAC_SLL_2(X, 1); \
q >>= 1; \
} \
q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1); \
while (q != _FP_WORK_ROUND) \
{ \
T##_f0 = S##_f0 + q; \
T##_f1 = S##_f1; \
if (T##_f1 < X##_f1 || \
(T##_f1 == X##_f1 && T##_f0 <= X##_f0)) \
{ \
S##_f0 = T##_f0 + q; \
S##_f1 += (T##_f0 > S##_f0); \
_FP_FRAC_DEC_2(X, T); \
R##_f0 += q; \
} \
_FP_FRAC_SLL_2(X, 1); \
q >>= 1; \
} \
if (X##_f0 | X##_f1) \
{ \
if (S##_f1 < X##_f1 || \
(S##_f1 == X##_f1 && S##_f0 < X##_f0)) \
R##_f0 |= _FP_WORK_ROUND; \
R##_f0 |= _FP_WORK_STICKY; \
} \
} while (0)
/*
* Assembly/disassembly for converting to/from integral types.
* No shifting or overflow handled here.
*/
#define _FP_FRAC_ASSEMBLE_2(r, X, rsize) \
do { \
if (rsize <= _FP_W_TYPE_SIZE) \
r = X##_f0; \
else \
{ \
r = X##_f1; \
r <<= _FP_W_TYPE_SIZE; \
r += X##_f0; \
} \
} while (0)
#define _FP_FRAC_DISASSEMBLE_2(X, r, rsize) \
do { \
X##_f0 = r; \
X##_f1 = (rsize <= _FP_W_TYPE_SIZE ? 0 : r >> _FP_W_TYPE_SIZE); \
} while (0)
/*
* Convert FP values between word sizes
*/
#define _FP_FRAC_CONV_1_2(dfs, sfs, D, S) \
do { \
if (S##_c != FP_CLS_NAN) \
_FP_FRAC_SRS_2(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs), \
_FP_WFRACBITS_##sfs); \
else \
_FP_FRAC_SRL_2(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs)); \
D##_f = S##_f0; \
} while (0)
#define _FP_FRAC_CONV_2_1(dfs, sfs, D, S) \
do { \
D##_f0 = S##_f; \
D##_f1 = 0; \
_FP_FRAC_SLL_2(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs)); \
} while (0)
#endif
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