sfp-machine.h

ARM 嵌入式 系统 设计与实例开发 实验教材 二源码

/* Machine-dependent software floating-point definitions.
   Sparc userland (_Q_*) version.
   Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Richard Henderson ([e-mail]),
		  Jakub Jelinek ([e-mail]),
		  David S. Miller ([e-mail]) and
		  Peter Maydell ([e-mail]).

   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

#include <linux/config.h>
   
#define _FP_W_TYPE_SIZE		32
#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_wide(_FP_WFRACBITS_S,R,X,Y,umul_ppmm)
#define _FP_MUL_MEAT_D(R,X,Y)					\
  _FP_MUL_MEAT_2_wide(_FP_WFRACBITS_D,R,X,Y,umul_ppmm)
#define _FP_MUL_MEAT_Q(R,X,Y)					\
  _FP_MUL_MEAT_4_wide(_FP_WFRACBITS_Q,R,X,Y,umul_ppmm)

#define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_udiv(S,R,X,Y)
#define _FP_DIV_MEAT_D(R,X,Y)	_FP_DIV_MEAT_2_udiv(D,R,X,Y)
#define _FP_DIV_MEAT_Q(R,X,Y)	_FP_DIV_MEAT_4_udiv(Q,R,X,Y)

#define _FP_NANFRAC_S		((_FP_QNANBIT_S << 1) - 1)
#define _FP_NANFRAC_D		((_FP_QNANBIT_D << 1) - 1), -1
#define _FP_NANFRAC_Q		((_FP_QNANBIT_Q << 1) - 1), -1, -1, -1
#define _FP_NANSIGN_S		0
#define _FP_NANSIGN_D		0
#define _FP_NANSIGN_Q		0

#define _FP_KEEPNANFRACP 1

/* If one NaN is signaling and the other is not,
 * we choose that one, otherwise we choose X.
 */
/* For _Qp_* and _Q_*, this should prefer X, for
 * CPU instruction emulation this should prefer Y.
 * (see SPAMv9 B.2.2 section).
 */
#define _FP_CHOOSENAN(fs, wc, R, X, Y, OP)			\
  do {								\
    if ((_FP_FRAC_HIGH_RAW_##fs(Y) & _FP_QNANBIT_##fs)		\
	&& !(_FP_FRAC_HIGH_RAW_##fs(X) & _FP_QNANBIT_##fs))	\
      {								\
	R##_s = X##_s;						\
	_FP_FRAC_COPY_##wc(R,X);				\
      }								\
    else							\
      {								\
	R##_s = Y##_s;						\
	_FP_FRAC_COPY_##wc(R,Y);				\
      }								\
    R##_c = FP_CLS_NAN;						\
  } while (0)

/* Some assembly to speed things up. */
#define __FP_FRAC_ADD_3(r2,r1,r0,x2,x1,x0,y2,y1,y0)			\
  __asm__ ("addcc %r7,%8,%2
	    addxcc %r5,%6,%1
	    addx %r3,%4,%0"						\
	   : "=r" ((USItype)(r2)),					\
	     "=&r" ((USItype)(r1)),					\
	     "=&r" ((USItype)(r0))					\
	   : "%rJ" ((USItype)(x2)),					\
	     "rI" ((USItype)(y2)),					\
	     "%rJ" ((USItype)(x1)),					\
	     "rI" ((USItype)(y1)),					\
	     "%rJ" ((USItype)(x0)),					\
	     "rI" ((USItype)(y0))					\
	   : "cc")

#define __FP_FRAC_SUB_3(r2,r1,r0,x2,x1,x0,y2,y1,y0)			\
  __asm__ ("subcc %r7,%8,%2
	    subxcc %r5,%6,%1
	    subx %r3,%4,%0"						\
	   : "=r" ((USItype)(r2)),					\
	     "=&r" ((USItype)(r1)),					\
	     "=&r" ((USItype)(r0))					\
	   : "%rJ" ((USItype)(x2)),					\
	     "rI" ((USItype)(y2)),					\
	     "%rJ" ((USItype)(x1)),					\
	     "rI" ((USItype)(y1)),					\
	     "%rJ" ((USItype)(x0)),					\
	     "rI" ((USItype)(y0))					\
	   : "cc")

#define __FP_FRAC_ADD_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0)		\
  do {									\
    /* We need to fool gcc,  as we need to pass more than 10		\
       input/outputs.  */						\
    register USItype _t1 __asm__ ("g1"), _t2 __asm__ ("g2");		\
    __asm__ __volatile__ ("
	    addcc %r8,%9,%1
	    addxcc %r6,%7,%0
	    addxcc %r4,%5,%%g2
	    addx %r2,%3,%%g1"						\
	   : "=&r" ((USItype)(r1)),					\
	     "=&r" ((USItype)(r0))					\
	   : "%rJ" ((USItype)(x3)),					\
	     "rI" ((USItype)(y3)),					\
	     "%rJ" ((USItype)(x2)),					\
	     "rI" ((USItype)(y2)),					\
	     "%rJ" ((USItype)(x1)),					\
	     "rI" ((USItype)(y1)),					\
	     "%rJ" ((USItype)(x0)),					\
	     "rI" ((USItype)(y0))					\
	   : "cc", "g1", "g2");						\
    __asm__ __volatile__ ("" : "=r" (_t1), "=r" (_t2));			\
    r3 = _t1; r2 = _t2;							\
  } while (0)

#define __FP_FRAC_SUB_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0)		\
  do {									\
    /* We need to fool gcc,  as we need to pass more than 10		\
       input/outputs.  */						\
    register USItype _t1 __asm__ ("g1"), _t2 __asm__ ("g2");		\
    __asm__ __volatile__ ("
	    subcc %r8,%9,%1
	    subxcc %r6,%7,%0
	    subxcc %r4,%5,%%g2
	    subx %r2,%3,%%g1"						\
	   : "=&r" ((USItype)(r1)),					\
	     "=&r" ((USItype)(r0))					\
	   : "%rJ" ((USItype)(x3)),					\
	     "rI" ((USItype)(y3)),					\
	     "%rJ" ((USItype)(x2)),					\
	     "rI" ((USItype)(y2)),					\
	     "%rJ" ((USItype)(x1)),					\
	     "rI" ((USItype)(y1)),					\
	     "%rJ" ((USItype)(x0)),					\
	     "rI" ((USItype)(y0))					\
	   : "cc", "g1", "g2");						\
    __asm__ __volatile__ ("" : "=r" (_t1), "=r" (_t2));			\
    r3 = _t1; r2 = _t2;							\
  } while (0)

#define __FP_FRAC_DEC_3(x2,x1,x0,y2,y1,y0) __FP_FRAC_SUB_3(x2,x1,x0,x2,x1,x0,y2,y1,y0)

#define __FP_FRAC_DEC_4(x3,x2,x1,x0,y3,y2,y1,y0) __FP_FRAC_SUB_4(x3,x2,x1,x0,x3,x2,x1,x0,y3,y2,y1,y0)

#define __FP_FRAC_ADDI_4(x3,x2,x1,x0,i)					\
  __asm__ ("addcc %3,%4,%3
	    addxcc %2,%%g0,%2
	    addxcc %1,%%g0,%1
	    addx %0,%%g0,%0"						\
	   : "=&r" ((USItype)(x3)),					\
	     "=&r" ((USItype)(x2)),					\
	     "=&r" ((USItype)(x1)),					\
	     "=&r" ((USItype)(x0))					\
	   : "rI" ((USItype)(i)),					\
	     "0" ((USItype)(x3)),					\
	     "1" ((USItype)(x2)),					\
	     "2" ((USItype)(x1)),					\
	     "3" ((USItype)(x0))					\
	   : "cc")

#ifndef CONFIG_SMP
extern struct task_struct *last_task_used_math;
#endif

/* Obtain the current rounding mode. */
#ifndef FP_ROUNDMODE
#ifdef CONFIG_SMP
#define FP_ROUNDMODE	((current->thread.fsr >> 30) & 0x3)
#else
#define FP_ROUNDMODE	((last_task_used_math->thread.fsr >> 30) & 0x3)
#endif
#endif

/* Exception flags. */
#define FP_EX_INVALID		(1 << 4)
#define FP_EX_OVERFLOW		(1 << 3)
#define FP_EX_UNDERFLOW		(1 << 2)
#define FP_EX_DIVZERO		(1 << 1)
#define FP_EX_INEXACT		(1 << 0)

#define FP_HANDLE_EXCEPTIONS return _fex

#ifdef CONFIG_SMP
#define FP_INHIBIT_RESULTS ((current->thread.fsr >> 23) & _fex)
#else
#define FP_INHIBIT_RESULTS ((last_task_used_math->thread.fsr >> 23) & _fex)
#endif

#endif