Archipelago » qemu

/*

    NetWinder Floating Point Emulator

    (c) Rebel.com, 1998-1999

    Direct questions, comments to Scott Bambrough <scottb@netwinder.org>

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by

    the Free Software Foundation; either version 2 of the License, or

    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License

    along with this program; if not, write to the Free Software

    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#ifndef __FPA11_H__

#define __FPA11_H__

#define GET_FPA11() (qemufpa)

/*

 * The processes registers are always at the very top of the 8K

 * stack+task struct.  Use the same method as 'current' uses to

 * reach them.

 */

extern unsigned int *user_registers;

#define GET_USERREG() (user_registers)

/* Need task_struct */

//#include <linux/sched.h>

/* includes */

#include "fpsr.h"                /* FP control and status register definitions */

#include "softfloat.h"

#define                typeNone                0x00

#define                typeSingle                0x01

#define                typeDouble                0x02

#define                typeExtended                0x03

/*

 * This must be no more and no less than 12 bytes.

 */

typedef union tagFPREG {

   floatx80 fExtended;

   float64  fDouble;

   float32  fSingle;

} FPREG;

/*

 * FPA11 device model.

 *

 * This structure is exported to user space.  Do not re-order.

 * Only add new stuff to the end, and do not change the size of

 * any element.  Elements of this structure are used by user

 * space, and must match struct user_fp in include/asm-arm/user.h.

 * We include the byte offsets below for documentation purposes.

 *

 * The size of this structure and FPREG are checked by fpmodule.c

 * on initialisation.  If the rules have been broken, NWFPE will

 * not initialise.

 */

typedef struct tagFPA11 {

/*   0 */  FPREG fpreg[8];                /* 8 floating point registers */

/*  96 */  FPSR fpsr;                        /* floating point status register */

/* 100 */  FPCR fpcr;                        /* floating point control register */

/* 104 */  unsigned char fType[8];        /* type of floating point value held in

                                           floating point registers.  One of none

                                           single, double or extended. */

/* 112 */  int initflag;                /* this is special.  The kernel guarantees

                                           to set it to 0 when a thread is launched,

                                           so we can use it to detect whether this

                                           instance of the emulator needs to be

                                           initialised. */

} FPA11;

extern FPA11* qemufpa;

extern void resetFPA11(void);

extern void SetRoundingMode(const unsigned int);

extern void SetRoundingPrecision(const unsigned int);

#define get_user(x,y) ((x)=*(y))

#define put_user(x,y) (*(y)=(x))

static inline unsigned int readRegister(unsigned int reg)

{

    return (user_registers[(reg)]);

}

static inline void writeRegister(unsigned int x, unsigned int y)

{

#if 0

        printf("writing %d to r%d\n",y,x);

#endif

        user_registers[(x)]=(y);

}

static inline void writeConditionCodes(unsigned int x)

{

#if 0

unsigned        int y;

unsigned    int ZF;

        printf("setting flags to %x from %x\n",x,user_registers[16]);

#endif

        user_registers[16]=(x);        // cpsr

        user_registers[17]=(x>>29)&1;        // cf

        user_registers[18]=(x<<3)&(1<<31);        // vf

        user_registers[19]=x&(1<<31);        // nzf

        if(!(x&(1<<30))) user_registers[19]++;        // nzf must be non-zero for zf to be cleared

#if 0

        ZF = (user_registers[19] == 0);

        y=user_registers[16] | (user_registers[19] & 0x80000000) | (ZF << 30) | 

                    (user_registers[17] << 29) | ((user_registers[18] & 0x80000000) >> 3);

        if(y != x)

                printf("GODDAM SHIIIIIIIIIIIIIIIIT! %x %x nzf %x zf %x\n",x,y,user_registers[19],ZF);

#endif                    

}

#define REG_PC 15

unsigned int EmulateAll(unsigned int opcode, FPA11* qfpa, unsigned int* qregs);

#endif