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[/] [openrisc/] [tags/] [gnu-src/] [gdb-6.8/] [pre-binutils-2.20.1-sync/] [sim/] [arm/] [thumbemu.c] - Diff between revs 157 and 223

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/*  thumbemu.c -- Thumb instruction emulation.
/*  thumbemu.c -- Thumb instruction emulation.
    Copyright (C) 1996, Cygnus Software Technologies Ltd.
    Copyright (C) 1996, Cygnus Software Technologies Ltd.
 
 
    This program is free software; you can redistribute it and/or modify
    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
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
    (at your option) any later version.
 
 
    This program is distributed in the hope that it will be useful,
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    GNU General Public License for more details.
 
 
    You should have received a copy of the GNU General Public License
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
 
 
/* We can provide simple Thumb simulation by decoding the Thumb
/* We can provide simple Thumb simulation by decoding the Thumb
instruction into its corresponding ARM instruction, and using the
instruction into its corresponding ARM instruction, and using the
existing ARM simulator.  */
existing ARM simulator.  */
 
 
#ifndef MODET                   /* required for the Thumb instruction support */
#ifndef MODET                   /* required for the Thumb instruction support */
#if 1
#if 1
#error "MODET needs to be defined for the Thumb world to work"
#error "MODET needs to be defined for the Thumb world to work"
#else
#else
#define MODET (1)
#define MODET (1)
#endif
#endif
#endif
#endif
 
 
#include "armdefs.h"
#include "armdefs.h"
#include "armemu.h"
#include "armemu.h"
#include "armos.h"
#include "armos.h"
 
 
/* Attempt to emulate an ARMv6 instruction.
/* Attempt to emulate an ARMv6 instruction.
   Stores t_branch into PVALUE upon success or t_undefined otherwise.  */
   Stores t_branch into PVALUE upon success or t_undefined otherwise.  */
 
 
static void
static void
handle_v6_thumb_insn (ARMul_State * state,
handle_v6_thumb_insn (ARMul_State * state,
                      ARMword       tinstr,
                      ARMword       tinstr,
                      tdstate *     pvalid)
                      tdstate *     pvalid)
{
{
  ARMword Rd;
  ARMword Rd;
  ARMword Rm;
  ARMword Rm;
 
 
  if (! state->is_v6)
  if (! state->is_v6)
    {
    {
      * pvalid = t_undefined;
      * pvalid = t_undefined;
      return;
      return;
    }
    }
 
 
  switch (tinstr & 0xFFC0)
  switch (tinstr & 0xFFC0)
    {
    {
    case 0xb660: /* cpsie */
    case 0xb660: /* cpsie */
    case 0xb670: /* cpsid */
    case 0xb670: /* cpsid */
    case 0x4600: /* cpy */
    case 0x4600: /* cpy */
    case 0xba00: /* rev */
    case 0xba00: /* rev */
    case 0xba40: /* rev16 */
    case 0xba40: /* rev16 */
    case 0xbac0: /* revsh */
    case 0xbac0: /* revsh */
    case 0xb650: /* setend */
    case 0xb650: /* setend */
    default:
    default:
      printf ("Unhandled v6 thumb insn: %04x\n", tinstr);
      printf ("Unhandled v6 thumb insn: %04x\n", tinstr);
      * pvalid = t_undefined;
      * pvalid = t_undefined;
      return;
      return;
 
 
    case 0xb200: /* sxth */
    case 0xb200: /* sxth */
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      if (Rm & 0x8000)
      if (Rm & 0x8000)
        state->Reg [(tinstr & 0x7)] = (Rm & 0xffff) | 0xffff0000;
        state->Reg [(tinstr & 0x7)] = (Rm & 0xffff) | 0xffff0000;
      else
      else
        state->Reg [(tinstr & 0x7)] = Rm & 0xffff;
        state->Reg [(tinstr & 0x7)] = Rm & 0xffff;
      break;
      break;
    case 0xb240: /* sxtb */
    case 0xb240: /* sxtb */
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      if (Rm & 0x80)
      if (Rm & 0x80)
        state->Reg [(tinstr & 0x7)] = (Rm & 0xff) | 0xffffff00;
        state->Reg [(tinstr & 0x7)] = (Rm & 0xff) | 0xffffff00;
      else
      else
        state->Reg [(tinstr & 0x7)] = Rm & 0xff;
        state->Reg [(tinstr & 0x7)] = Rm & 0xff;
      break;
      break;
    case 0xb280: /* uxth */
    case 0xb280: /* uxth */
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      state->Reg [(tinstr & 0x7)] = Rm & 0xffff;
      state->Reg [(tinstr & 0x7)] = Rm & 0xffff;
      break;
      break;
    case 0xb2c0: /* uxtb */
    case 0xb2c0: /* uxtb */
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      Rm = state->Reg [(tinstr & 0x38) >> 3];
      state->Reg [(tinstr & 0x7)] = Rm & 0xff;
      state->Reg [(tinstr & 0x7)] = Rm & 0xff;
      break;
      break;
    }
    }
  /* Indicate that the instruction has been processed.  */
  /* Indicate that the instruction has been processed.  */
  * pvalid = t_branch;
  * pvalid = t_branch;
}
}
 
 
/* Decode a 16bit Thumb instruction.  The instruction is in the low
/* Decode a 16bit Thumb instruction.  The instruction is in the low
   16-bits of the tinstr field, with the following Thumb instruction
   16-bits of the tinstr field, with the following Thumb instruction
   held in the high 16-bits.  Passing in two Thumb instructions allows
   held in the high 16-bits.  Passing in two Thumb instructions allows
   easier simulation of the special dual BL instruction.  */
   easier simulation of the special dual BL instruction.  */
 
 
tdstate
tdstate
ARMul_ThumbDecode (ARMul_State * state,
ARMul_ThumbDecode (ARMul_State * state,
                   ARMword       pc,
                   ARMword       pc,
                   ARMword       tinstr,
                   ARMword       tinstr,
                   ARMword *     ainstr)
                   ARMword *     ainstr)
{
{
  tdstate valid = t_decoded;    /* default assumes a valid instruction */
  tdstate valid = t_decoded;    /* default assumes a valid instruction */
  ARMword next_instr;
  ARMword next_instr;
 
 
  if (state->bigendSig)
  if (state->bigendSig)
    {
    {
      next_instr = tinstr & 0xFFFF;
      next_instr = tinstr & 0xFFFF;
      tinstr >>= 16;
      tinstr >>= 16;
    }
    }
  else
  else
    {
    {
      next_instr = tinstr >> 16;
      next_instr = tinstr >> 16;
      tinstr &= 0xFFFF;
      tinstr &= 0xFFFF;
    }
    }
 
 
#if 1                           /* debugging to catch non updates */
#if 1                           /* debugging to catch non updates */
  *ainstr = 0xDEADC0DE;
  *ainstr = 0xDEADC0DE;
#endif
#endif
 
 
  switch ((tinstr & 0xF800) >> 11)
  switch ((tinstr & 0xF800) >> 11)
    {
    {
    case 0:                      /* LSL */
    case 0:                      /* LSL */
    case 1:                     /* LSR */
    case 1:                     /* LSR */
    case 2:                     /* ASR */
    case 2:                     /* ASR */
      /* Format 1 */
      /* Format 1 */
      *ainstr = 0xE1B00000      /* base opcode */
      *ainstr = 0xE1B00000      /* base opcode */
        | ((tinstr & 0x1800) >> (11 - 5))       /* shift type */
        | ((tinstr & 0x1800) >> (11 - 5))       /* shift type */
        | ((tinstr & 0x07C0) << (7 - 6))        /* imm5 */
        | ((tinstr & 0x07C0) << (7 - 6))        /* imm5 */
        | ((tinstr & 0x0038) >> 3)      /* Rs */
        | ((tinstr & 0x0038) >> 3)      /* Rs */
        | ((tinstr & 0x0007) << 12);    /* Rd */
        | ((tinstr & 0x0007) << 12);    /* Rd */
      break;
      break;
    case 3:                     /* ADD/SUB */
    case 3:                     /* ADD/SUB */
      /* Format 2 */
      /* Format 2 */
      {
      {
        ARMword subset[4] = {
        ARMword subset[4] = {
          0xE0900000,           /* ADDS Rd,Rs,Rn    */
          0xE0900000,           /* ADDS Rd,Rs,Rn    */
          0xE0500000,           /* SUBS Rd,Rs,Rn    */
          0xE0500000,           /* SUBS Rd,Rs,Rn    */
          0xE2900000,           /* ADDS Rd,Rs,#imm3 */
          0xE2900000,           /* ADDS Rd,Rs,#imm3 */
          0xE2500000            /* SUBS Rd,Rs,#imm3 */
          0xE2500000            /* SUBS Rd,Rs,#imm3 */
        };
        };
        /* It is quicker indexing into a table, than performing switch
        /* It is quicker indexing into a table, than performing switch
           or conditionals: */
           or conditionals: */
        *ainstr = subset[(tinstr & 0x0600) >> 9]        /* base opcode */
        *ainstr = subset[(tinstr & 0x0600) >> 9]        /* base opcode */
          | ((tinstr & 0x01C0) >> 6)    /* Rn or imm3 */
          | ((tinstr & 0x01C0) >> 6)    /* Rn or imm3 */
          | ((tinstr & 0x0038) << (16 - 3))     /* Rs */
          | ((tinstr & 0x0038) << (16 - 3))     /* Rs */
          | ((tinstr & 0x0007) << (12 - 0));     /* Rd */
          | ((tinstr & 0x0007) << (12 - 0));     /* Rd */
      }
      }
      break;
      break;
    case 4:                     /* MOV */
    case 4:                     /* MOV */
    case 5:                     /* CMP */
    case 5:                     /* CMP */
    case 6:                     /* ADD */
    case 6:                     /* ADD */
    case 7:                     /* SUB */
    case 7:                     /* SUB */
      /* Format 3 */
      /* Format 3 */
      {
      {
        ARMword subset[4] = {
        ARMword subset[4] = {
          0xE3B00000,           /* MOVS Rd,#imm8    */
          0xE3B00000,           /* MOVS Rd,#imm8    */
          0xE3500000,           /* CMP  Rd,#imm8    */
          0xE3500000,           /* CMP  Rd,#imm8    */
          0xE2900000,           /* ADDS Rd,Rd,#imm8 */
          0xE2900000,           /* ADDS Rd,Rd,#imm8 */
          0xE2500000,           /* SUBS Rd,Rd,#imm8 */
          0xE2500000,           /* SUBS Rd,Rd,#imm8 */
        };
        };
        *ainstr = subset[(tinstr & 0x1800) >> 11]       /* base opcode */
        *ainstr = subset[(tinstr & 0x1800) >> 11]       /* base opcode */
          | ((tinstr & 0x00FF) >> 0)     /* imm8 */
          | ((tinstr & 0x00FF) >> 0)     /* imm8 */
          | ((tinstr & 0x0700) << (16 - 8))     /* Rn */
          | ((tinstr & 0x0700) << (16 - 8))     /* Rn */
          | ((tinstr & 0x0700) << (12 - 8));    /* Rd */
          | ((tinstr & 0x0700) << (12 - 8));    /* Rd */
      }
      }
      break;
      break;
    case 8:                     /* Arithmetic and high register transfers */
    case 8:                     /* Arithmetic and high register transfers */
      /* TODO: Since the subsets for both Format 4 and Format 5
      /* TODO: Since the subsets for both Format 4 and Format 5
         instructions are made up of different ARM encodings, we could
         instructions are made up of different ARM encodings, we could
         save the following conditional, and just have one large
         save the following conditional, and just have one large
         subset. */
         subset. */
      if ((tinstr & (1 << 10)) == 0)
      if ((tinstr & (1 << 10)) == 0)
        {
        {
          /* Format 4 */
          /* Format 4 */
          struct
          struct
          {
          {
            ARMword opcode;
            ARMword opcode;
            enum
            enum
            { t_norm, t_shift, t_neg, t_mul }
            { t_norm, t_shift, t_neg, t_mul }
            otype;
            otype;
          }
          }
          subset[16] =
          subset[16] =
          {
          {
            { 0xE0100000, t_norm},                      /* ANDS Rd,Rd,Rs     */
            { 0xE0100000, t_norm},                      /* ANDS Rd,Rd,Rs     */
            { 0xE0300000, t_norm},                      /* EORS Rd,Rd,Rs     */
            { 0xE0300000, t_norm},                      /* EORS Rd,Rd,Rs     */
            { 0xE1B00010, t_shift},                     /* MOVS Rd,Rd,LSL Rs */
            { 0xE1B00010, t_shift},                     /* MOVS Rd,Rd,LSL Rs */
            { 0xE1B00030, t_shift},                     /* MOVS Rd,Rd,LSR Rs */
            { 0xE1B00030, t_shift},                     /* MOVS Rd,Rd,LSR Rs */
            { 0xE1B00050, t_shift},                     /* MOVS Rd,Rd,ASR Rs */
            { 0xE1B00050, t_shift},                     /* MOVS Rd,Rd,ASR Rs */
            { 0xE0B00000, t_norm},                      /* ADCS Rd,Rd,Rs     */
            { 0xE0B00000, t_norm},                      /* ADCS Rd,Rd,Rs     */
            { 0xE0D00000, t_norm},                      /* SBCS Rd,Rd,Rs     */
            { 0xE0D00000, t_norm},                      /* SBCS Rd,Rd,Rs     */
            { 0xE1B00070, t_shift},                     /* MOVS Rd,Rd,ROR Rs */
            { 0xE1B00070, t_shift},                     /* MOVS Rd,Rd,ROR Rs */
            { 0xE1100000, t_norm},                      /* TST  Rd,Rs        */
            { 0xE1100000, t_norm},                      /* TST  Rd,Rs        */
            { 0xE2700000, t_neg},                       /* RSBS Rd,Rs,#0     */
            { 0xE2700000, t_neg},                       /* RSBS Rd,Rs,#0     */
            { 0xE1500000, t_norm},                      /* CMP  Rd,Rs        */
            { 0xE1500000, t_norm},                      /* CMP  Rd,Rs        */
            { 0xE1700000, t_norm},                      /* CMN  Rd,Rs        */
            { 0xE1700000, t_norm},                      /* CMN  Rd,Rs        */
            { 0xE1900000, t_norm},                      /* ORRS Rd,Rd,Rs     */
            { 0xE1900000, t_norm},                      /* ORRS Rd,Rd,Rs     */
            { 0xE0100090, t_mul} ,                      /* MULS Rd,Rd,Rs     */
            { 0xE0100090, t_mul} ,                      /* MULS Rd,Rd,Rs     */
            { 0xE1D00000, t_norm},                      /* BICS Rd,Rd,Rs     */
            { 0xE1D00000, t_norm},                      /* BICS Rd,Rd,Rs     */
            { 0xE1F00000, t_norm}       /* MVNS Rd,Rs        */
            { 0xE1F00000, t_norm}       /* MVNS Rd,Rs        */
          };
          };
          *ainstr = subset[(tinstr & 0x03C0) >> 6].opcode;      /* base */
          *ainstr = subset[(tinstr & 0x03C0) >> 6].opcode;      /* base */
          switch (subset[(tinstr & 0x03C0) >> 6].otype)
          switch (subset[(tinstr & 0x03C0) >> 6].otype)
            {
            {
            case t_norm:
            case t_norm:
              *ainstr |= ((tinstr & 0x0007) << 16)      /* Rn */
              *ainstr |= ((tinstr & 0x0007) << 16)      /* Rn */
                | ((tinstr & 0x0007) << 12)     /* Rd */
                | ((tinstr & 0x0007) << 12)     /* Rd */
                | ((tinstr & 0x0038) >> 3);     /* Rs */
                | ((tinstr & 0x0038) >> 3);     /* Rs */
              break;
              break;
            case t_shift:
            case t_shift:
              *ainstr |= ((tinstr & 0x0007) << 12)      /* Rd */
              *ainstr |= ((tinstr & 0x0007) << 12)      /* Rd */
                | ((tinstr & 0x0007) >> 0)       /* Rm */
                | ((tinstr & 0x0007) >> 0)       /* Rm */
                | ((tinstr & 0x0038) << (8 - 3));       /* Rs */
                | ((tinstr & 0x0038) << (8 - 3));       /* Rs */
              break;
              break;
            case t_neg:
            case t_neg:
              *ainstr |= ((tinstr & 0x0007) << 12)      /* Rd */
              *ainstr |= ((tinstr & 0x0007) << 12)      /* Rd */
                | ((tinstr & 0x0038) << (16 - 3));      /* Rn */
                | ((tinstr & 0x0038) << (16 - 3));      /* Rn */
              break;
              break;
            case t_mul:
            case t_mul:
              *ainstr |= ((tinstr & 0x0007) << 16)      /* Rd */
              *ainstr |= ((tinstr & 0x0007) << 16)      /* Rd */
                | ((tinstr & 0x0007) << 8)      /* Rs */
                | ((tinstr & 0x0007) << 8)      /* Rs */
                | ((tinstr & 0x0038) >> 3);     /* Rm */
                | ((tinstr & 0x0038) >> 3);     /* Rm */
              break;
              break;
            }
            }
        }
        }
      else
      else
        {
        {
          /* Format 5 */
          /* Format 5 */
          ARMword Rd = ((tinstr & 0x0007) >> 0);
          ARMword Rd = ((tinstr & 0x0007) >> 0);
          ARMword Rs = ((tinstr & 0x0038) >> 3);
          ARMword Rs = ((tinstr & 0x0038) >> 3);
          if (tinstr & (1 << 7))
          if (tinstr & (1 << 7))
            Rd += 8;
            Rd += 8;
          if (tinstr & (1 << 6))
          if (tinstr & (1 << 6))
            Rs += 8;
            Rs += 8;
          switch ((tinstr & 0x03C0) >> 6)
          switch ((tinstr & 0x03C0) >> 6)
            {
            {
            case 0x1:           /* ADD Rd,Rd,Hs */
            case 0x1:           /* ADD Rd,Rd,Hs */
            case 0x2:           /* ADD Hd,Hd,Rs */
            case 0x2:           /* ADD Hd,Hd,Rs */
            case 0x3:           /* ADD Hd,Hd,Hs */
            case 0x3:           /* ADD Hd,Hd,Hs */
              *ainstr = 0xE0800000      /* base */
              *ainstr = 0xE0800000      /* base */
                | (Rd << 16)    /* Rn */
                | (Rd << 16)    /* Rn */
                | (Rd << 12)    /* Rd */
                | (Rd << 12)    /* Rd */
                | (Rs << 0);     /* Rm */
                | (Rs << 0);     /* Rm */
              break;
              break;
            case 0x5:           /* CMP Rd,Hs */
            case 0x5:           /* CMP Rd,Hs */
            case 0x6:           /* CMP Hd,Rs */
            case 0x6:           /* CMP Hd,Rs */
            case 0x7:           /* CMP Hd,Hs */
            case 0x7:           /* CMP Hd,Hs */
              *ainstr = 0xE1500000      /* base */
              *ainstr = 0xE1500000      /* base */
                | (Rd << 16)    /* Rn */
                | (Rd << 16)    /* Rn */
                | (Rd << 12)    /* Rd */
                | (Rd << 12)    /* Rd */
                | (Rs << 0);     /* Rm */
                | (Rs << 0);     /* Rm */
              break;
              break;
            case 0x9:           /* MOV Rd,Hs */
            case 0x9:           /* MOV Rd,Hs */
            case 0xA:           /* MOV Hd,Rs */
            case 0xA:           /* MOV Hd,Rs */
            case 0xB:           /* MOV Hd,Hs */
            case 0xB:           /* MOV Hd,Hs */
              *ainstr = 0xE1A00000      /* base */
              *ainstr = 0xE1A00000      /* base */
                | (Rd << 16)    /* Rn */
                | (Rd << 16)    /* Rn */
                | (Rd << 12)    /* Rd */
                | (Rd << 12)    /* Rd */
                | (Rs << 0);     /* Rm */
                | (Rs << 0);     /* Rm */
              break;
              break;
            case 0xC:           /* BX Rs */
            case 0xC:           /* BX Rs */
            case 0xD:           /* BX Hs */
            case 0xD:           /* BX Hs */
              *ainstr = 0xE12FFF10      /* base */
              *ainstr = 0xE12FFF10      /* base */
                | ((tinstr & 0x0078) >> 3);     /* Rd */
                | ((tinstr & 0x0078) >> 3);     /* Rd */
              break;
              break;
            case 0xE:           /* UNDEFINED */
            case 0xE:           /* UNDEFINED */
            case 0xF:           /* UNDEFINED */
            case 0xF:           /* UNDEFINED */
              if (state->is_v5)
              if (state->is_v5)
                {
                {
                  /* BLX Rs; BLX Hs */
                  /* BLX Rs; BLX Hs */
                  *ainstr = 0xE12FFF30  /* base */
                  *ainstr = 0xE12FFF30  /* base */
                    | ((tinstr & 0x0078) >> 3); /* Rd */
                    | ((tinstr & 0x0078) >> 3); /* Rd */
                  break;
                  break;
                }
                }
              /* Drop through.  */
              /* Drop through.  */
            case 0x0:           /* UNDEFINED */
            case 0x0:           /* UNDEFINED */
            case 0x4:           /* UNDEFINED */
            case 0x4:           /* UNDEFINED */
            case 0x8:           /* UNDEFINED */
            case 0x8:           /* UNDEFINED */
              handle_v6_thumb_insn (state, tinstr, & valid);
              handle_v6_thumb_insn (state, tinstr, & valid);
              break;
              break;
            }
            }
        }
        }
      break;
      break;
    case 9:                     /* LDR Rd,[PC,#imm8] */
    case 9:                     /* LDR Rd,[PC,#imm8] */
      /* Format 6 */
      /* Format 6 */
      *ainstr = 0xE59F0000      /* base */
      *ainstr = 0xE59F0000      /* base */
        | ((tinstr & 0x0700) << (12 - 8))       /* Rd */
        | ((tinstr & 0x0700) << (12 - 8))       /* Rd */
        | ((tinstr & 0x00FF) << (2 - 0));        /* off8 */
        | ((tinstr & 0x00FF) << (2 - 0));        /* off8 */
      break;
      break;
    case 10:
    case 10:
    case 11:
    case 11:
      /* TODO: Format 7 and Format 8 perform the same ARM encoding, so
      /* TODO: Format 7 and Format 8 perform the same ARM encoding, so
         the following could be merged into a single subset, saving on
         the following could be merged into a single subset, saving on
         the following boolean: */
         the following boolean: */
      if ((tinstr & (1 << 9)) == 0)
      if ((tinstr & (1 << 9)) == 0)
        {
        {
          /* Format 7 */
          /* Format 7 */
          ARMword subset[4] = {
          ARMword subset[4] = {
            0xE7800000,         /* STR  Rd,[Rb,Ro] */
            0xE7800000,         /* STR  Rd,[Rb,Ro] */
            0xE7C00000,         /* STRB Rd,[Rb,Ro] */
            0xE7C00000,         /* STRB Rd,[Rb,Ro] */
            0xE7900000,         /* LDR  Rd,[Rb,Ro] */
            0xE7900000,         /* LDR  Rd,[Rb,Ro] */
            0xE7D00000          /* LDRB Rd,[Rb,Ro] */
            0xE7D00000          /* LDRB Rd,[Rb,Ro] */
          };
          };
          *ainstr = subset[(tinstr & 0x0C00) >> 10]     /* base */
          *ainstr = subset[(tinstr & 0x0C00) >> 10]     /* base */
            | ((tinstr & 0x0007) << (12 - 0))    /* Rd */
            | ((tinstr & 0x0007) << (12 - 0))    /* Rd */
            | ((tinstr & 0x0038) << (16 - 3))   /* Rb */
            | ((tinstr & 0x0038) << (16 - 3))   /* Rb */
            | ((tinstr & 0x01C0) >> 6); /* Ro */
            | ((tinstr & 0x01C0) >> 6); /* Ro */
        }
        }
      else
      else
        {
        {
          /* Format 8 */
          /* Format 8 */
          ARMword subset[4] = {
          ARMword subset[4] = {
            0xE18000B0,         /* STRH  Rd,[Rb,Ro] */
            0xE18000B0,         /* STRH  Rd,[Rb,Ro] */
            0xE19000D0,         /* LDRSB Rd,[Rb,Ro] */
            0xE19000D0,         /* LDRSB Rd,[Rb,Ro] */
            0xE19000B0,         /* LDRH  Rd,[Rb,Ro] */
            0xE19000B0,         /* LDRH  Rd,[Rb,Ro] */
            0xE19000F0          /* LDRSH Rd,[Rb,Ro] */
            0xE19000F0          /* LDRSH Rd,[Rb,Ro] */
          };
          };
          *ainstr = subset[(tinstr & 0x0C00) >> 10]     /* base */
          *ainstr = subset[(tinstr & 0x0C00) >> 10]     /* base */
            | ((tinstr & 0x0007) << (12 - 0))    /* Rd */
            | ((tinstr & 0x0007) << (12 - 0))    /* Rd */
            | ((tinstr & 0x0038) << (16 - 3))   /* Rb */
            | ((tinstr & 0x0038) << (16 - 3))   /* Rb */
            | ((tinstr & 0x01C0) >> 6); /* Ro */
            | ((tinstr & 0x01C0) >> 6); /* Ro */
        }
        }
      break;
      break;
    case 12:                    /* STR Rd,[Rb,#imm5] */
    case 12:                    /* STR Rd,[Rb,#imm5] */
    case 13:                    /* LDR Rd,[Rb,#imm5] */
    case 13:                    /* LDR Rd,[Rb,#imm5] */
    case 14:                    /* STRB Rd,[Rb,#imm5] */
    case 14:                    /* STRB Rd,[Rb,#imm5] */
    case 15:                    /* LDRB Rd,[Rb,#imm5] */
    case 15:                    /* LDRB Rd,[Rb,#imm5] */
      /* Format 9 */
      /* Format 9 */
      {
      {
        ARMword subset[4] = {
        ARMword subset[4] = {
          0xE5800000,           /* STR  Rd,[Rb,#imm5] */
          0xE5800000,           /* STR  Rd,[Rb,#imm5] */
          0xE5900000,           /* LDR  Rd,[Rb,#imm5] */
          0xE5900000,           /* LDR  Rd,[Rb,#imm5] */
          0xE5C00000,           /* STRB Rd,[Rb,#imm5] */
          0xE5C00000,           /* STRB Rd,[Rb,#imm5] */
          0xE5D00000            /* LDRB Rd,[Rb,#imm5] */
          0xE5D00000            /* LDRB Rd,[Rb,#imm5] */
        };
        };
        /* The offset range defends on whether we are transferring a
        /* The offset range defends on whether we are transferring a
           byte or word value: */
           byte or word value: */
        *ainstr = subset[(tinstr & 0x1800) >> 11]       /* base */
        *ainstr = subset[(tinstr & 0x1800) >> 11]       /* base */
          | ((tinstr & 0x0007) << (12 - 0))      /* Rd */
          | ((tinstr & 0x0007) << (12 - 0))      /* Rd */
          | ((tinstr & 0x0038) << (16 - 3))     /* Rb */
          | ((tinstr & 0x0038) << (16 - 3))     /* Rb */
          | ((tinstr & 0x07C0) >> (6 - ((tinstr & (1 << 12)) ? 0 : 2))); /* off5 */
          | ((tinstr & 0x07C0) >> (6 - ((tinstr & (1 << 12)) ? 0 : 2))); /* off5 */
      }
      }
      break;
      break;
    case 16:                    /* STRH Rd,[Rb,#imm5] */
    case 16:                    /* STRH Rd,[Rb,#imm5] */
    case 17:                    /* LDRH Rd,[Rb,#imm5] */
    case 17:                    /* LDRH Rd,[Rb,#imm5] */
      /* Format 10 */
      /* Format 10 */
      *ainstr = ((tinstr & (1 << 11))   /* base */
      *ainstr = ((tinstr & (1 << 11))   /* base */
                 ? 0xE1D000B0   /* LDRH */
                 ? 0xE1D000B0   /* LDRH */
                 : 0xE1C000B0)  /* STRH */
                 : 0xE1C000B0)  /* STRH */
        | ((tinstr & 0x0007) << (12 - 0))        /* Rd */
        | ((tinstr & 0x0007) << (12 - 0))        /* Rd */
        | ((tinstr & 0x0038) << (16 - 3))       /* Rb */
        | ((tinstr & 0x0038) << (16 - 3))       /* Rb */
        | ((tinstr & 0x01C0) >> (6 - 1))        /* off5, low nibble */
        | ((tinstr & 0x01C0) >> (6 - 1))        /* off5, low nibble */
        | ((tinstr & 0x0600) >> (9 - 8));       /* off5, high nibble */
        | ((tinstr & 0x0600) >> (9 - 8));       /* off5, high nibble */
      break;
      break;
    case 18:                    /* STR Rd,[SP,#imm8] */
    case 18:                    /* STR Rd,[SP,#imm8] */
    case 19:                    /* LDR Rd,[SP,#imm8] */
    case 19:                    /* LDR Rd,[SP,#imm8] */
      /* Format 11 */
      /* Format 11 */
      *ainstr = ((tinstr & (1 << 11))   /* base */
      *ainstr = ((tinstr & (1 << 11))   /* base */
                 ? 0xE59D0000   /* LDR */
                 ? 0xE59D0000   /* LDR */
                 : 0xE58D0000)  /* STR */
                 : 0xE58D0000)  /* STR */
        | ((tinstr & 0x0700) << (12 - 8))       /* Rd */
        | ((tinstr & 0x0700) << (12 - 8))       /* Rd */
        | ((tinstr & 0x00FF) << 2);     /* off8 */
        | ((tinstr & 0x00FF) << 2);     /* off8 */
      break;
      break;
    case 20:                    /* ADD Rd,PC,#imm8 */
    case 20:                    /* ADD Rd,PC,#imm8 */
    case 21:                    /* ADD Rd,SP,#imm8 */
    case 21:                    /* ADD Rd,SP,#imm8 */
      /* Format 12 */
      /* Format 12 */
      if ((tinstr & (1 << 11)) == 0)
      if ((tinstr & (1 << 11)) == 0)
        {
        {
          /* NOTE: The PC value used here should by word aligned */
          /* NOTE: The PC value used here should by word aligned */
          /* We encode shift-left-by-2 in the rotate immediate field,
          /* We encode shift-left-by-2 in the rotate immediate field,
             so no shift of off8 is needed.  */
             so no shift of off8 is needed.  */
          *ainstr = 0xE28F0F00  /* base */
          *ainstr = 0xE28F0F00  /* base */
            | ((tinstr & 0x0700) << (12 - 8))   /* Rd */
            | ((tinstr & 0x0700) << (12 - 8))   /* Rd */
            | (tinstr & 0x00FF);        /* off8 */
            | (tinstr & 0x00FF);        /* off8 */
        }
        }
      else
      else
        {
        {
          /* We encode shift-left-by-2 in the rotate immediate field,
          /* We encode shift-left-by-2 in the rotate immediate field,
             so no shift of off8 is needed.  */
             so no shift of off8 is needed.  */
          *ainstr = 0xE28D0F00  /* base */
          *ainstr = 0xE28D0F00  /* base */
            | ((tinstr & 0x0700) << (12 - 8))   /* Rd */
            | ((tinstr & 0x0700) << (12 - 8))   /* Rd */
            | (tinstr & 0x00FF);        /* off8 */
            | (tinstr & 0x00FF);        /* off8 */
        }
        }
      break;
      break;
    case 22:
    case 22:
    case 23:
    case 23:
      switch (tinstr & 0x0F00)
      switch (tinstr & 0x0F00)
        {
        {
        case 0x0000:
        case 0x0000:
          /* Format 13 */
          /* Format 13 */
          /* NOTE: The instruction contains a shift left of 2
          /* NOTE: The instruction contains a shift left of 2
             equivalent (implemented as ROR #30):  */
             equivalent (implemented as ROR #30):  */
          *ainstr = ((tinstr & (1 << 7))        /* base */
          *ainstr = ((tinstr & (1 << 7))        /* base */
                     ? 0xE24DDF00       /* SUB */
                     ? 0xE24DDF00       /* SUB */
                     : 0xE28DDF00)      /* ADD */
                     : 0xE28DDF00)      /* ADD */
            | (tinstr & 0x007F);        /* off7 */
            | (tinstr & 0x007F);        /* off7 */
          break;
          break;
        case 0x0400:
        case 0x0400:
          /* Format 14 - Push */
          /* Format 14 - Push */
          * ainstr = 0xE92D0000 | (tinstr & 0x00FF);
          * ainstr = 0xE92D0000 | (tinstr & 0x00FF);
          break;
          break;
        case 0x0500:
        case 0x0500:
          /* Format 14 - Push + LR */
          /* Format 14 - Push + LR */
          * ainstr = 0xE92D4000 | (tinstr & 0x00FF);
          * ainstr = 0xE92D4000 | (tinstr & 0x00FF);
          break;
          break;
        case 0x0c00:
        case 0x0c00:
          /* Format 14 - Pop */
          /* Format 14 - Pop */
          * ainstr = 0xE8BD0000 | (tinstr & 0x00FF);
          * ainstr = 0xE8BD0000 | (tinstr & 0x00FF);
          break;
          break;
        case 0x0d00:
        case 0x0d00:
          /* Format 14 - Pop + PC */
          /* Format 14 - Pop + PC */
          * ainstr = 0xE8BD8000 | (tinstr & 0x00FF);
          * ainstr = 0xE8BD8000 | (tinstr & 0x00FF);
          break;
          break;
        case 0x0e00:
        case 0x0e00:
          if (state->is_v5)
          if (state->is_v5)
            {
            {
              /* This is normally an undefined instruction.  The v5t architecture
              /* This is normally an undefined instruction.  The v5t architecture
                 defines this particular pattern as a BKPT instruction, for
                 defines this particular pattern as a BKPT instruction, for
                 hardware assisted debugging.  We map onto the arm BKPT
                 hardware assisted debugging.  We map onto the arm BKPT
                 instruction.  */
                 instruction.  */
              * ainstr = 0xE1200070 | ((tinstr & 0xf0) << 4) | (tinstr & 0xf);
              * ainstr = 0xE1200070 | ((tinstr & 0xf0) << 4) | (tinstr & 0xf);
              break;
              break;
            }
            }
          /* Drop through.  */
          /* Drop through.  */
        default:
        default:
          /* Everything else is an undefined instruction.  */
          /* Everything else is an undefined instruction.  */
          handle_v6_thumb_insn (state, tinstr, & valid);
          handle_v6_thumb_insn (state, tinstr, & valid);
          break;
          break;
        }
        }
      break;
      break;
    case 24:                    /* STMIA */
    case 24:                    /* STMIA */
    case 25:                    /* LDMIA */
    case 25:                    /* LDMIA */
      /* Format 15 */
      /* Format 15 */
      *ainstr = ((tinstr & (1 << 11))   /* base */
      *ainstr = ((tinstr & (1 << 11))   /* base */
                 ? 0xE8B00000   /* LDMIA */
                 ? 0xE8B00000   /* LDMIA */
                 : 0xE8A00000)  /* STMIA */
                 : 0xE8A00000)  /* STMIA */
        | ((tinstr & 0x0700) << (16 - 8))       /* Rb */
        | ((tinstr & 0x0700) << (16 - 8))       /* Rb */
        | (tinstr & 0x00FF);    /* mask8 */
        | (tinstr & 0x00FF);    /* mask8 */
      break;
      break;
    case 26:                    /* Bcc */
    case 26:                    /* Bcc */
    case 27:                    /* Bcc/SWI */
    case 27:                    /* Bcc/SWI */
      if ((tinstr & 0x0F00) == 0x0F00)
      if ((tinstr & 0x0F00) == 0x0F00)
        {
        {
          /* Format 17 : SWI */
          /* Format 17 : SWI */
          *ainstr = 0xEF000000;
          *ainstr = 0xEF000000;
          /* Breakpoint must be handled specially.  */
          /* Breakpoint must be handled specially.  */
          if ((tinstr & 0x00FF) == 0x18)
          if ((tinstr & 0x00FF) == 0x18)
            *ainstr |= ((tinstr & 0x00FF) << 16);
            *ainstr |= ((tinstr & 0x00FF) << 16);
          /* New breakpoint value.  See gdb/arm-tdep.c  */
          /* New breakpoint value.  See gdb/arm-tdep.c  */
          else if ((tinstr & 0x00FF) == 0xFE)
          else if ((tinstr & 0x00FF) == 0xFE)
            *ainstr |= SWI_Breakpoint;
            *ainstr |= SWI_Breakpoint;
          else
          else
            *ainstr |= (tinstr & 0x00FF);
            *ainstr |= (tinstr & 0x00FF);
        }
        }
      else if ((tinstr & 0x0F00) != 0x0E00)
      else if ((tinstr & 0x0F00) != 0x0E00)
        {
        {
          /* Format 16 */
          /* Format 16 */
          int doit = FALSE;
          int doit = FALSE;
          /* TODO: Since we are doing a switch here, we could just add
          /* TODO: Since we are doing a switch here, we could just add
             the SWI and undefined instruction checks into this
             the SWI and undefined instruction checks into this
             switch to same on a couple of conditionals: */
             switch to same on a couple of conditionals: */
          switch ((tinstr & 0x0F00) >> 8)
          switch ((tinstr & 0x0F00) >> 8)
            {
            {
            case EQ:
            case EQ:
              doit = ZFLAG;
              doit = ZFLAG;
              break;
              break;
            case NE:
            case NE:
              doit = !ZFLAG;
              doit = !ZFLAG;
              break;
              break;
            case VS:
            case VS:
              doit = VFLAG;
              doit = VFLAG;
              break;
              break;
            case VC:
            case VC:
              doit = !VFLAG;
              doit = !VFLAG;
              break;
              break;
            case MI:
            case MI:
              doit = NFLAG;
              doit = NFLAG;
              break;
              break;
            case PL:
            case PL:
              doit = !NFLAG;
              doit = !NFLAG;
              break;
              break;
            case CS:
            case CS:
              doit = CFLAG;
              doit = CFLAG;
              break;
              break;
            case CC:
            case CC:
              doit = !CFLAG;
              doit = !CFLAG;
              break;
              break;
            case HI:
            case HI:
              doit = (CFLAG && !ZFLAG);
              doit = (CFLAG && !ZFLAG);
              break;
              break;
            case LS:
            case LS:
              doit = (!CFLAG || ZFLAG);
              doit = (!CFLAG || ZFLAG);
              break;
              break;
            case GE:
            case GE:
              doit = ((!NFLAG && !VFLAG) || (NFLAG && VFLAG));
              doit = ((!NFLAG && !VFLAG) || (NFLAG && VFLAG));
              break;
              break;
            case LT:
            case LT:
              doit = ((NFLAG && !VFLAG) || (!NFLAG && VFLAG));
              doit = ((NFLAG && !VFLAG) || (!NFLAG && VFLAG));
              break;
              break;
            case GT:
            case GT:
              doit = ((!NFLAG && !VFLAG && !ZFLAG)
              doit = ((!NFLAG && !VFLAG && !ZFLAG)
                      || (NFLAG && VFLAG && !ZFLAG));
                      || (NFLAG && VFLAG && !ZFLAG));
              break;
              break;
            case LE:
            case LE:
              doit = ((NFLAG && !VFLAG) || (!NFLAG && VFLAG)) || ZFLAG;
              doit = ((NFLAG && !VFLAG) || (!NFLAG && VFLAG)) || ZFLAG;
              break;
              break;
            }
            }
          if (doit)
          if (doit)
            {
            {
              state->Reg[15] = (pc + 4
              state->Reg[15] = (pc + 4
                                + (((tinstr & 0x7F) << 1)
                                + (((tinstr & 0x7F) << 1)
                                   | ((tinstr & (1 << 7)) ? 0xFFFFFF00 : 0)));
                                   | ((tinstr & (1 << 7)) ? 0xFFFFFF00 : 0)));
              FLUSHPIPE;
              FLUSHPIPE;
            }
            }
          valid = t_branch;
          valid = t_branch;
        }
        }
      else
      else
        /* UNDEFINED : cc=1110(AL) uses different format.  */
        /* UNDEFINED : cc=1110(AL) uses different format.  */
        handle_v6_thumb_insn (state, tinstr, & valid);
        handle_v6_thumb_insn (state, tinstr, & valid);
      break;
      break;
    case 28:                    /* B */
    case 28:                    /* B */
      /* Format 18 */
      /* Format 18 */
      state->Reg[15] = (pc + 4
      state->Reg[15] = (pc + 4
                        + (((tinstr & 0x3FF) << 1)
                        + (((tinstr & 0x3FF) << 1)
                           | ((tinstr & (1 << 10)) ? 0xFFFFF800 : 0)));
                           | ((tinstr & (1 << 10)) ? 0xFFFFF800 : 0)));
      FLUSHPIPE;
      FLUSHPIPE;
      valid = t_branch;
      valid = t_branch;
      break;
      break;
    case 29:                    /* UNDEFINED */
    case 29:                    /* UNDEFINED */
      if (state->is_v5)
      if (state->is_v5)
        {
        {
          if (tinstr & 1)
          if (tinstr & 1)
            {
            {
              handle_v6_thumb_insn (state, tinstr, & valid);
              handle_v6_thumb_insn (state, tinstr, & valid);
              break;
              break;
            }
            }
          /* Drop through.  */
          /* Drop through.  */
 
 
          /* Format 19 */
          /* Format 19 */
          /* There is no single ARM instruction equivalent for this
          /* There is no single ARM instruction equivalent for this
             instruction. Also, it should only ever be matched with the
             instruction. Also, it should only ever be matched with the
             fmt19 "BL/BLX instruction 1" instruction.  However, we do
             fmt19 "BL/BLX instruction 1" instruction.  However, we do
             allow the simulation of it on its own, with undefined results
             allow the simulation of it on its own, with undefined results
             if r14 is not suitably initialised.  */
             if r14 is not suitably initialised.  */
          {
          {
            ARMword tmp = (pc + 2);
            ARMword tmp = (pc + 2);
 
 
            state->Reg[15] = ((state->Reg[14] + ((tinstr & 0x07FF) << 1))
            state->Reg[15] = ((state->Reg[14] + ((tinstr & 0x07FF) << 1))
                              & 0xFFFFFFFC);
                              & 0xFFFFFFFC);
            CLEART;
            CLEART;
            state->Reg[14] = (tmp | 1);
            state->Reg[14] = (tmp | 1);
            valid = t_branch;
            valid = t_branch;
            FLUSHPIPE;
            FLUSHPIPE;
            break;
            break;
          }
          }
        }
        }
 
 
      handle_v6_thumb_insn (state, tinstr, & valid);
      handle_v6_thumb_insn (state, tinstr, & valid);
      break;
      break;
 
 
    case 30:                    /* BL instruction 1 */
    case 30:                    /* BL instruction 1 */
      /* Format 19 */
      /* Format 19 */
      /* There is no single ARM instruction equivalent for this Thumb
      /* There is no single ARM instruction equivalent for this Thumb
         instruction. To keep the simulation simple (from the user
         instruction. To keep the simulation simple (from the user
         perspective) we check if the following instruction is the
         perspective) we check if the following instruction is the
         second half of this BL, and if it is we simulate it
         second half of this BL, and if it is we simulate it
         immediately.  */
         immediately.  */
      state->Reg[14] = state->Reg[15] \
      state->Reg[14] = state->Reg[15] \
        + (((tinstr & 0x07FF) << 12) \
        + (((tinstr & 0x07FF) << 12) \
           | ((tinstr & (1 << 10)) ? 0xFF800000 : 0));
           | ((tinstr & (1 << 10)) ? 0xFF800000 : 0));
 
 
      valid = t_branch;         /* in-case we don't have the 2nd half */
      valid = t_branch;         /* in-case we don't have the 2nd half */
      tinstr = next_instr;      /* move the instruction down */
      tinstr = next_instr;      /* move the instruction down */
      pc += 2;                  /* point the pc at the 2nd half */
      pc += 2;                  /* point the pc at the 2nd half */
      if (((tinstr & 0xF800) >> 11) != 31)
      if (((tinstr & 0xF800) >> 11) != 31)
        {
        {
          if (((tinstr & 0xF800) >> 11) == 29)
          if (((tinstr & 0xF800) >> 11) == 29)
            {
            {
              ARMword tmp = (pc + 2);
              ARMword tmp = (pc + 2);
 
 
              state->Reg[15] = ((state->Reg[14]
              state->Reg[15] = ((state->Reg[14]
                                 + ((tinstr & 0x07FE) << 1))
                                 + ((tinstr & 0x07FE) << 1))
                                & 0xFFFFFFFC);
                                & 0xFFFFFFFC);
              CLEART;
              CLEART;
              state->Reg[14] = (tmp | 1);
              state->Reg[14] = (tmp | 1);
              valid = t_branch;
              valid = t_branch;
              FLUSHPIPE;
              FLUSHPIPE;
            }
            }
          else
          else
            /* Exit, since not correct instruction. */
            /* Exit, since not correct instruction. */
            pc -= 2;
            pc -= 2;
          break;
          break;
        }
        }
      /* else we fall through to process the second half of the BL */
      /* else we fall through to process the second half of the BL */
      pc += 2;                  /* point the pc at the 2nd half */
      pc += 2;                  /* point the pc at the 2nd half */
    case 31:                    /* BL instruction 2 */
    case 31:                    /* BL instruction 2 */
      /* Format 19 */
      /* Format 19 */
      /* There is no single ARM instruction equivalent for this
      /* There is no single ARM instruction equivalent for this
         instruction. Also, it should only ever be matched with the
         instruction. Also, it should only ever be matched with the
         fmt19 "BL instruction 1" instruction. However, we do allow
         fmt19 "BL instruction 1" instruction. However, we do allow
         the simulation of it on its own, with undefined results if
         the simulation of it on its own, with undefined results if
         r14 is not suitably initialised.  */
         r14 is not suitably initialised.  */
      {
      {
        ARMword tmp = pc;
        ARMword tmp = pc;
 
 
        state->Reg[15] = (state->Reg[14] + ((tinstr & 0x07FF) << 1));
        state->Reg[15] = (state->Reg[14] + ((tinstr & 0x07FF) << 1));
        state->Reg[14] = (tmp | 1);
        state->Reg[14] = (tmp | 1);
        valid = t_branch;
        valid = t_branch;
        FLUSHPIPE;
        FLUSHPIPE;
      }
      }
      break;
      break;
    }
    }
 
 
  return valid;
  return valid;
}
}
 
 

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