1. 根目录:
2. arch
3. alpha
4. include
5. asm
6. sfp-machine.h

/* Machine-dependent software floating-point definitions.
   Alpha kernel version.
   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 (jakub@redhat.com) and
		  David S. Miller (davem@redhat.com).

   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 _SFP_MACHINE_H
#define _SFP_MACHINE_H
   
#define _FP_W_TYPE_SIZE		64
#define _FP_W_TYPE		unsigned long
#define _FP_WS_TYPE		signed long
#define _FP_I_TYPE		long

#define _FP_MUL_MEAT_S(R,X,Y)					\
  _FP_MUL_MEAT_1_imm(_FP_WFRACBITS_S,R,X,Y)
#define _FP_MUL_MEAT_D(R,X,Y)					\
  _FP_MUL_MEAT_1_wide(_FP_WFRACBITS_D,R,X,Y,umul_ppmm)
#define _FP_MUL_MEAT_Q(R,X,Y)					\
  _FP_MUL_MEAT_2_wide(_FP_WFRACBITS_Q,R,X,Y,umul_ppmm)

#define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_imm(S,R,X,Y,_FP_DIV_HELP_imm)
#define _FP_DIV_MEAT_D(R,X,Y)	_FP_DIV_MEAT_1_udiv(D,R,X,Y)
#define _FP_DIV_MEAT_Q(R,X,Y)	_FP_DIV_MEAT_2_udiv(Q,R,X,Y)

#define _FP_NANFRAC_S		_FP_QNANBIT_S
#define _FP_NANFRAC_D		_FP_QNANBIT_D
#define _FP_NANFRAC_Q		_FP_QNANBIT_Q
#define _FP_NANSIGN_S		1
#define _FP_NANSIGN_D		1
#define _FP_NANSIGN_Q		1

#define _FP_KEEPNANFRACP 1

/* Alpha Architecture Handbook, 4.7.10.4 sais that
 * we should prefer any type of NaN in Fb, then Fa.
 */
#define _FP_CHOOSENAN(fs, wc, R, X, Y, OP)			\
  do {								\
    R##_s = Y##_s;						\
    _FP_FRAC_COPY_##wc(R,X);					\
    R##_c = FP_CLS_NAN;						\
  } while (0)

/* Obtain the current rounding mode. */
#define FP_ROUNDMODE	mode
#define FP_RND_NEAREST	(FPCR_DYN_NORMAL >> FPCR_DYN_SHIFT)
#define FP_RND_ZERO	(FPCR_DYN_CHOPPED >> FPCR_DYN_SHIFT)
#define FP_RND_PINF	(FPCR_DYN_PLUS >> FPCR_DYN_SHIFT)
#define FP_RND_MINF	(FPCR_DYN_MINUS >> FPCR_DYN_SHIFT)

/* Exception flags. */
#define FP_EX_INVALID		IEEE_TRAP_ENABLE_INV
#define FP_EX_OVERFLOW		IEEE_TRAP_ENABLE_OVF
#define FP_EX_UNDERFLOW		IEEE_TRAP_ENABLE_UNF
#define FP_EX_DIVZERO		IEEE_TRAP_ENABLE_DZE
#define FP_EX_INEXACT		IEEE_TRAP_ENABLE_INE
#define FP_EX_DENORM		IEEE_TRAP_ENABLE_DNO

#define FP_DENORM_ZERO		(swcr & IEEE_MAP_DMZ)

/* We write the results always */
#define FP_INHIBIT_RESULTS 0

#endif