Archipelago » qemu

/*

    NetWinder Floating Point Emulator

    (c) Rebel.com, 1998-1999

    (c) Philip Blundell, 1998

    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.

*/

#include "fpa11.h"

#include "softfloat.h"

#include "fpopcode.h"

//#include "fpmodule.h"

//#include "fpmodule.inl"

//#include <asm/uaccess.h>

static inline

void loadSingle(const unsigned int Fn,const unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   fpa11->fType[Fn] = typeSingle;

   get_user(fpa11->fpreg[Fn].fSingle, pMem);

}

static inline

void loadDouble(const unsigned int Fn,const unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   unsigned int *p;

   p = (unsigned int*)&fpa11->fpreg[Fn].fDouble;

   fpa11->fType[Fn] = typeDouble;

#ifdef WORDS_BIGENDIAN

   get_user(p[0], &pMem[0]); /* sign & exponent */

   get_user(p[1], &pMem[1]);

#else

   get_user(p[0], &pMem[1]);

   get_user(p[1], &pMem[0]); /* sign & exponent */

#endif

}   

static inline

void loadExtended(const unsigned int Fn,const unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   unsigned int *p;

   p = (unsigned int*)&fpa11->fpreg[Fn].fExtended;

   fpa11->fType[Fn] = typeExtended;

   get_user(p[0], &pMem[0]);  /* sign & exponent */

   get_user(p[1], &pMem[2]);  /* ls bits */

   get_user(p[2], &pMem[1]);  /* ms bits */

}   

static inline

void loadMultiple(const unsigned int Fn,const unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   register unsigned int *p;

   unsigned long x;

   p = (unsigned int*)&(fpa11->fpreg[Fn]);

   get_user(x, &pMem[0]);

   fpa11->fType[Fn] = (x >> 14) & 0x00000003;

   switch (fpa11->fType[Fn])

   {

      case typeSingle:

      case typeDouble:

      {

         get_user(p[0], &pMem[2]);  /* Single */

         get_user(p[1], &pMem[1]);  /* double msw */

         p[2] = 0;        /* empty */

      }

      break; 

      case typeExtended:

      {

         get_user(p[1], &pMem[2]);

         get_user(p[2], &pMem[1]);  /* msw */

         p[0] = (x & 0x80003fff);      

      }

      break;

   }

}

static inline

void storeSingle(const unsigned int Fn,unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   float32 val;

   register unsigned int *p = (unsigned int*)&val;

   switch (fpa11->fType[Fn])

   {

      case typeDouble: 

         val = float64_to_float32(fpa11->fpreg[Fn].fDouble);

      break;

      case typeExtended: 

         val = floatx80_to_float32(fpa11->fpreg[Fn].fExtended);

      break;

      default: val = fpa11->fpreg[Fn].fSingle;

   }

   put_user(p[0], pMem);

}   

static inline

void storeDouble(const unsigned int Fn,unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   float64 val;

   register unsigned int *p = (unsigned int*)&val;

   switch (fpa11->fType[Fn])

   {

      case typeSingle: 

         val = float32_to_float64(fpa11->fpreg[Fn].fSingle);

      break;

      case typeExtended:

         val = floatx80_to_float64(fpa11->fpreg[Fn].fExtended);

      break;

      default: val = fpa11->fpreg[Fn].fDouble;

   }

#ifdef WORDS_BIGENDIAN

   put_user(p[0], &pMem[0]);        /* msw */

   put_user(p[1], &pMem[1]);        /* lsw */

#else

   put_user(p[1], &pMem[0]);        /* msw */

   put_user(p[0], &pMem[1]);        /* lsw */

#endif

}   

static inline

void storeExtended(const unsigned int Fn,unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   floatx80 val;

   register unsigned int *p = (unsigned int*)&val;

   switch (fpa11->fType[Fn])

   {

      case typeSingle: 

         val = float32_to_floatx80(fpa11->fpreg[Fn].fSingle);

      break;

      case typeDouble: 

         val = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);

      break;

      default: val = fpa11->fpreg[Fn].fExtended;

   }

   put_user(p[0], &pMem[0]); /* sign & exp */

   put_user(p[1], &pMem[2]);

   put_user(p[2], &pMem[1]); /* msw */

}   

static inline

void storeMultiple(const unsigned int Fn,unsigned int *pMem)

{

   FPA11 *fpa11 = GET_FPA11();

   register unsigned int nType, *p;

   p = (unsigned int*)&(fpa11->fpreg[Fn]);

   nType = fpa11->fType[Fn];

   switch (nType)

   {

      case typeSingle:

      case typeDouble:

      {

         put_user(p[0], &pMem[2]); /* single */

         put_user(p[1], &pMem[1]); /* double msw */

         put_user(nType << 14, &pMem[0]);

      }

      break; 

      case typeExtended:

      {

         put_user(p[2], &pMem[1]); /* msw */

         put_user(p[1], &pMem[2]);

         put_user((p[0] & 0x80003fff) | (nType << 14), &pMem[0]);

      }

      break;

   }

}

unsigned int PerformLDF(const unsigned int opcode)

{

   unsigned int *pBase, *pAddress, *pFinal, nRc = 1,

     write_back = WRITE_BACK(opcode);

   //printk("PerformLDF(0x%08x), Fd = 0x%08x\n",opcode,getFd(opcode));

   pBase = (unsigned int*)readRegister(getRn(opcode));

   if (REG_PC == getRn(opcode))

   {

     pBase += 2;

     write_back = 0;

   }

   pFinal = pBase;

   if (BIT_UP_SET(opcode))

     pFinal += getOffset(opcode);

   else

     pFinal -= getOffset(opcode);

   if (PREINDEXED(opcode)) pAddress = pFinal; else pAddress = pBase;

   switch (opcode & MASK_TRANSFER_LENGTH)

   {

      case TRANSFER_SINGLE  : loadSingle(getFd(opcode),pAddress);   break;

      case TRANSFER_DOUBLE  : loadDouble(getFd(opcode),pAddress);   break;

      case TRANSFER_EXTENDED: loadExtended(getFd(opcode),pAddress); break;

      default: nRc = 0;

   }

   if (write_back) writeRegister(getRn(opcode),(unsigned int)pFinal);

   return nRc;

}

unsigned int PerformSTF(const unsigned int opcode)

{

   unsigned int *pBase, *pAddress, *pFinal, nRc = 1,

     write_back = WRITE_BACK(opcode);

   //printk("PerformSTF(0x%08x), Fd = 0x%08x\n",opcode,getFd(opcode));

   SetRoundingMode(ROUND_TO_NEAREST);

   pBase = (unsigned int*)readRegister(getRn(opcode));

   if (REG_PC == getRn(opcode))

   {

     pBase += 2;

     write_back = 0;

   }

   pFinal = pBase;

   if (BIT_UP_SET(opcode))

     pFinal += getOffset(opcode);

   else

     pFinal -= getOffset(opcode);

   if (PREINDEXED(opcode)) pAddress = pFinal; else pAddress = pBase;

   switch (opcode & MASK_TRANSFER_LENGTH)

   {

      case TRANSFER_SINGLE  : storeSingle(getFd(opcode),pAddress);   break;

      case TRANSFER_DOUBLE  : storeDouble(getFd(opcode),pAddress);   break;

      case TRANSFER_EXTENDED: storeExtended(getFd(opcode),pAddress); break;

      default: nRc = 0;

   }

   if (write_back) writeRegister(getRn(opcode),(unsigned int)pFinal);

   return nRc;

}

unsigned int PerformLFM(const unsigned int opcode)

{

   unsigned int i, Fd, *pBase, *pAddress, *pFinal,

     write_back = WRITE_BACK(opcode);

   pBase = (unsigned int*)readRegister(getRn(opcode));

   if (REG_PC == getRn(opcode))

   {

     pBase += 2;

     write_back = 0;

   }

   pFinal = pBase;

   if (BIT_UP_SET(opcode))

     pFinal += getOffset(opcode);

   else

     pFinal -= getOffset(opcode);

   if (PREINDEXED(opcode)) pAddress = pFinal; else pAddress = pBase;

   Fd = getFd(opcode);

   for (i=getRegisterCount(opcode);i>0;i--)

   {

     loadMultiple(Fd,pAddress);

     pAddress += 3; Fd++;

     if (Fd == 8) Fd = 0;

   }

   if (write_back) writeRegister(getRn(opcode),(unsigned int)pFinal);

   return 1;

}

unsigned int PerformSFM(const unsigned int opcode)

{

   unsigned int i, Fd, *pBase, *pAddress, *pFinal,

     write_back = WRITE_BACK(opcode);

   pBase = (unsigned int*)readRegister(getRn(opcode));

   if (REG_PC == getRn(opcode))

   {

     pBase += 2;

     write_back = 0;

   }

   pFinal = pBase;

   if (BIT_UP_SET(opcode))

     pFinal += getOffset(opcode);

   else

     pFinal -= getOffset(opcode);

   if (PREINDEXED(opcode)) pAddress = pFinal; else pAddress = pBase;

   Fd = getFd(opcode);

   for (i=getRegisterCount(opcode);i>0;i--)

   {

     storeMultiple(Fd,pAddress);

     pAddress += 3; Fd++;

     if (Fd == 8) Fd = 0;

   }

   if (write_back) writeRegister(getRn(opcode),(unsigned int)pFinal);

   return 1;

}

#if 1

unsigned int EmulateCPDT(const unsigned int opcode)

{

  unsigned int nRc = 0;

  //printk("EmulateCPDT(0x%08x)\n",opcode);

  if (LDF_OP(opcode))

  {

    nRc = PerformLDF(opcode);

  }

  else if (LFM_OP(opcode))

  {

    nRc = PerformLFM(opcode);

  }

  else if (STF_OP(opcode))

  {

    nRc = PerformSTF(opcode);

  } 

  else if (SFM_OP(opcode))

  {

    nRc = PerformSFM(opcode);

  }

  else

  {

    nRc = 0;

  }

  return nRc;

}

#endif