i386-dis.c

qemu虚拟机代码

  info->private_data = (PTR) &priv;
  priv.max_fetched = priv.the_buffer;
  priv.insn_start = pc;

  obuf[0] = 0;
  op1out[0] = 0;
  op2out[0] = 0;
  op3out[0] = 0;

  op_index[0] = op_index[1] = op_index[2] = -1;

  the_info = info;
  start_pc = pc;
  start_codep = priv.the_buffer;
  codep = priv.the_buffer;

  if (setjmp (priv.bailout) != 0)
    {
      const char *name;

      /* Getting here means we tried for data but didn't get it.  That
	 means we have an incomplete instruction of some sort.  Just
	 print the first byte as a prefix or a .byte pseudo-op.  */
      if (codep > priv.the_buffer)
	{
	  name = prefix_name (priv.the_buffer[0], priv.orig_sizeflag);
	  if (name != NULL)
	    (*info->fprintf_func) (info->stream, "%s", name);
	  else
	    {
	      /* Just print the first byte as a .byte instruction.  */
	      (*info->fprintf_func) (info->stream, ".byte 0x%x",
				     (unsigned int) priv.the_buffer[0]);
	    }

	  return 1;
	}

      return -1;
    }

  obufp = obuf;
  ckprefix ();

  insn_codep = codep;
  sizeflag = priv.orig_sizeflag;

  FETCH_DATA (info, codep + 1);
  two_source_ops = (*codep == 0x62) || (*codep == 0xc8);

  if ((prefixes & PREFIX_FWAIT)
      && ((*codep < 0xd8) || (*codep > 0xdf)))
    {
      const char *name;

      /* fwait not followed by floating point instruction.  Print the
         first prefix, which is probably fwait itself.  */
      name = prefix_name (priv.the_buffer[0], priv.orig_sizeflag);
      if (name == NULL)
	name = INTERNAL_DISASSEMBLER_ERROR;
      (*info->fprintf_func) (info->stream, "%s", name);
      return 1;
    }

  if (*codep == 0x0f)
    {
      FETCH_DATA (info, codep + 2);
      dp = &dis386_twobyte[*++codep];
      need_modrm = twobyte_has_modrm[*codep];
      uses_SSE_prefix = twobyte_uses_SSE_prefix[*codep];
    }
  else
    {
      dp = &dis386[*codep];
      need_modrm = onebyte_has_modrm[*codep];
      uses_SSE_prefix = 0;
    }
  codep++;

  if (!uses_SSE_prefix && (prefixes & PREFIX_REPZ))
    {
      oappend ("repz ");
      used_prefixes |= PREFIX_REPZ;
    }
  if (!uses_SSE_prefix && (prefixes & PREFIX_REPNZ))
    {
      oappend ("repnz ");
      used_prefixes |= PREFIX_REPNZ;
    }
  if (prefixes & PREFIX_LOCK)
    {
      oappend ("lock ");
      used_prefixes |= PREFIX_LOCK;
    }

  if (prefixes & PREFIX_ADDR)
    {
      sizeflag ^= AFLAG;
      if (dp->bytemode3 != loop_jcxz_mode || intel_syntax)
	{
	  if ((sizeflag & AFLAG) || mode_64bit)
	    oappend ("addr32 ");
	  else
	    oappend ("addr16 ");
	  used_prefixes |= PREFIX_ADDR;
	}
    }

  if (!uses_SSE_prefix && (prefixes & PREFIX_DATA))
    {
      sizeflag ^= DFLAG;
      if (dp->bytemode3 == cond_jump_mode
	  && dp->bytemode1 == v_mode
	  && !intel_syntax)
	{
	  if (sizeflag & DFLAG)
	    oappend ("data32 ");
	  else
	    oappend ("data16 ");
	  used_prefixes |= PREFIX_DATA;
	}
    }

  if (need_modrm)
    {
      FETCH_DATA (info, codep + 1);
      mod = (*codep >> 6) & 3;
      reg = (*codep >> 3) & 7;
      rm = *codep & 7;
    }

  if (dp->name == NULL && dp->bytemode1 == FLOATCODE)
    {
      dofloat (sizeflag);
    }
  else
    {
      int index;
      if (dp->name == NULL)
	{
	  switch (dp->bytemode1)
	    {
	    case USE_GROUPS:
	      dp = &grps[dp->bytemode2][reg];
	      break;

	    case USE_PREFIX_USER_TABLE:
	      index = 0;
	      used_prefixes |= (prefixes & PREFIX_REPZ);
	      if (prefixes & PREFIX_REPZ)
		index = 1;
	      else
		{
		  used_prefixes |= (prefixes & PREFIX_DATA);
		  if (prefixes & PREFIX_DATA)
		    index = 2;
		  else
		    {
		      used_prefixes |= (prefixes & PREFIX_REPNZ);
		      if (prefixes & PREFIX_REPNZ)
			index = 3;
		    }
		}
	      dp = &prefix_user_table[dp->bytemode2][index];
	      break;

	    case X86_64_SPECIAL:
	      dp = &x86_64_table[dp->bytemode2][mode_64bit];
	      break;

	    default:
	      oappend (INTERNAL_DISASSEMBLER_ERROR);
	      break;
	    }
	}

      if (putop (dp->name, sizeflag) == 0)
	{
	  obufp = op1out;
	  op_ad = 2;
	  if (dp->op1)
	    (*dp->op1) (dp->bytemode1, sizeflag);

	  obufp = op2out;
	  op_ad = 1;
	  if (dp->op2)
	    (*dp->op2) (dp->bytemode2, sizeflag);

	  obufp = op3out;
	  op_ad = 0;
	  if (dp->op3)
	    (*dp->op3) (dp->bytemode3, sizeflag);
	}
    }

  /* See if any prefixes were not used.  If so, print the first one
     separately.  If we don't do this, we'll wind up printing an
     instruction stream which does not precisely correspond to the
     bytes we are disassembling.  */
  if ((prefixes & ~used_prefixes) != 0)
    {
      const char *name;

      name = prefix_name (priv.the_buffer[0], priv.orig_sizeflag);
      if (name == NULL)
	name = INTERNAL_DISASSEMBLER_ERROR;
      (*info->fprintf_func) (info->stream, "%s", name);
      return 1;
    }
  if (rex & ~rex_used)
    {
      const char *name;
      name = prefix_name (rex | 0x40, priv.orig_sizeflag);
      if (name == NULL)
	name = INTERNAL_DISASSEMBLER_ERROR;
      (*info->fprintf_func) (info->stream, "%s ", name);
    }

  obufp = obuf + strlen (obuf);
  for (i = strlen (obuf); i < 6; i++)
    oappend (" ");
  oappend (" ");
  (*info->fprintf_func) (info->stream, "%s", obuf);

  /* The enter and bound instructions are printed with operands in the same
     order as the intel book; everything else is printed in reverse order.  */
  if (intel_syntax || two_source_ops)
    {
      first = op1out;
      second = op2out;
      third = op3out;
      op_ad = op_index[0];
      op_index[0] = op_index[2];
      op_index[2] = op_ad;
    }
  else
    {
      first = op3out;
      second = op2out;
      third = op1out;
    }
  needcomma = 0;
  if (*first)
    {
      if (op_index[0] != -1 && !op_riprel[0])
	(*info->print_address_func) ((bfd_vma) op_address[op_index[0]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", first);
      needcomma = 1;
    }
  if (*second)
    {
      if (needcomma)
	(*info->fprintf_func) (info->stream, ",");
      if (op_index[1] != -1 && !op_riprel[1])
	(*info->print_address_func) ((bfd_vma) op_address[op_index[1]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", second);
      needcomma = 1;
    }
  if (*third)
    {
      if (needcomma)
	(*info->fprintf_func) (info->stream, ",");
      if (op_index[2] != -1 && !op_riprel[2])
	(*info->print_address_func) ((bfd_vma) op_address[op_index[2]], info);
      else
	(*info->fprintf_func) (info->stream, "%s", third);
    }
  for (i = 0; i < 3; i++)
    if (op_index[i] != -1 && op_riprel[i])
      {
	(*info->fprintf_func) (info->stream, "        # ");
	(*info->print_address_func) ((bfd_vma) (start_pc + codep - start_codep
						+ op_address[op_index[i]]), info);
      }
  return codep - priv.the_buffer;
}

static const char *float_mem[] = {
  /* d8 */
  "fadd{s||s|}",
  "fmul{s||s|}",
  "fcom{s||s|}",
  "fcomp{s||s|}",
  "fsub{s||s|}",
  "fsubr{s||s|}",
  "fdiv{s||s|}",
  "fdivr{s||s|}",
  /*  d9 */
  "fld{s||s|}",
  "(bad)",
  "fst{s||s|}",
  "fstp{s||s|}",
  "fldenv",
  "fldcw",
  "fNstenv",
  "fNstcw",
  /* da */
  "fiadd{l||l|}",
  "fimul{l||l|}",
  "ficom{l||l|}",
  "ficomp{l||l|}",
  "fisub{l||l|}",
  "fisubr{l||l|}",
  "fidiv{l||l|}",
  "fidivr{l||l|}",
  /* db */
  "fild{l||l|}",
  "(bad)",
  "fist{l||l|}",
  "fistp{l||l|}",
  "(bad)",
  "fld{t||t|}",
  "(bad)",
  "fstp{t||t|}",
  /* dc */
  "fadd{l||l|}",
  "fmul{l||l|}",
  "fcom{l||l|}",
  "fcomp{l||l|}",
  "fsub{l||l|}",
  "fsubr{l||l|}",
  "fdiv{l||l|}",
  "fdivr{l||l|}",
  /* dd */
  "fld{l||l|}",
  "(bad)",
  "fst{l||l|}",
  "fstp{l||l|}",
  "frstor",
  "(bad)",
  "fNsave",
  "fNstsw",
  /* de */
  "fiadd",
  "fimul",
  "ficom",
  "ficomp",
  "fisub",
  "fisubr",
  "fidiv",
  "fidivr",
  /* df */
  "fild",
  "(bad)",
  "fist",
  "fistp",
  "fbld",
  "fild{ll||ll|}",
  "fbstp",
  "fistpll",
};

#define ST OP_ST, 0
#define STi OP_STi, 0

#define FGRPd9_2 NULL, NULL, 0, NULL, 0, NULL, 0
#define FGRPd9_4 NULL, NULL, 1, NULL, 0, NULL, 0
#define FGRPd9_5 NULL, NULL, 2, NULL, 0, NULL, 0
#define FGRPd9_6 NULL, NULL, 3, NULL, 0, NULL, 0
#define FGRPd9_7 NULL, NULL, 4, NULL, 0, NULL, 0
#define FGRPda_5 NULL, NULL, 5, NULL, 0, NULL, 0
#define FGRPdb_4 NULL, NULL, 6, NULL, 0, NULL, 0
#define FGRPde_3 NULL, NULL, 7, NULL, 0, NULL, 0
#define FGRPdf_4 NULL, NULL, 8, NULL, 0, NULL, 0

static const struct dis386 float_reg[][8] = {
  /* d8 */
  {
    { "fadd",	ST, STi, XX },
    { "fmul",	ST, STi, XX },
    { "fcom",	STi, XX, XX },
    { "fcomp",	STi, XX, XX },
    { "fsub",	ST, STi, XX },
    { "fsubr",	ST, STi, XX },
    { "fdiv",	ST, STi, XX },
    { "fdivr",	ST, STi, XX },
  },
  /* d9 */
  {
    { "fld",	STi, XX, XX },
    { "fxch",	STi, XX, XX },
    { FGRPd9_2 },
    { "(bad)",	XX, XX, XX },
    { FGRPd9_4 },
    { FGRPd9_5 },
    { FGRPd9_6 },
    { FGRPd9_7 },
  },
  /* da */
  {
    { "fcmovb",	ST, STi, XX },
    { "fcmove",	ST, STi, XX },
    { "fcmovbe",ST, STi, XX },
    { "fcmovu",	ST, STi, XX },
    { "(bad)",	XX, XX, XX },
    { FGRPda_5 },
    { "(bad)",	XX, XX, XX },
    { "(bad)",	XX, XX, XX },
  },
  /* db */
  {
    { "fcmovnb",ST, STi, XX },
    { "fcmovne",ST, STi, XX },
    { "fcmovnbe",ST, STi, XX },
    { "fcmovnu",ST, STi, XX },
    { FGRPdb_4 },
    { "fucomi",	ST, STi, XX },
    { "fcomi",	ST, STi, XX },
    { "(bad)",	XX, XX, XX },
  },
  /* dc */
  {
    { "fadd",	STi, ST, XX },
    { "fmul",	STi, ST, XX },
    { "(bad)",	XX, XX, XX },
    { "(bad)",	XX, XX, XX },
#if UNIXWARE_COMPAT
    { "fsub",	STi, ST, XX },
    { "fsubr",	STi, ST, XX },
    { "fdiv",	STi, ST, XX },
    { "fdivr",	STi, ST, XX },
#else
    { "fsubr",	STi, ST, XX },
    { "fsub",	STi, ST, XX },
    { "fdivr",	STi, ST, XX },
    { "fdiv",	STi, ST, XX },
#endif
  },
  /* dd */
  {
    { "ffree",	STi, XX, XX },
    { "(bad)",	XX, XX, XX },
    { "fst",	STi, XX, XX },
    { "fstp",	STi, XX, XX },
    { "fucom",	STi, XX, XX },
    { "fucomp",	STi, XX, XX },
    { "(bad)",	XX, XX, XX },
    { "(bad)",	XX, XX, XX },
  },
  /* de */
  {
    { "faddp",	STi, ST, XX },
    { "fmulp",	STi, ST, XX },
    { "(bad)",	XX, XX, XX },
    { FGRPde_3 },
#if UNIXWARE_COMPAT
    { "fsubp",	STi, ST, XX },
    { "fsubrp",	STi, ST, XX },
    { "fdivp",	STi, ST, XX },
    { "fdivrp",	STi, ST, XX },
#else
    { "fsubrp",	STi, ST, XX },
    { "fsubp",	STi, ST, XX },
    { "fdivrp",	STi, ST, XX },
    { "fdivp",	STi, ST, XX },
#endif
  },
  /* df */
  {
    { "ffreep",	STi, XX, XX },
    { "(bad)",	XX, XX, XX },
    { "(bad)",	XX, XX, XX },
    { "(bad)",	XX, XX, XX },
    { FGRPdf_4 },
    { "fucomip",ST, STi, XX },
    { "fcomip", ST, STi, XX },
    { "(bad)",	XX, XX, XX },
  },
};

static char *fgrps[][8] = {
  /* d9_2  0 */
  {
    "fnop","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)","(bad)",
  },

  /* d9_4  1 */
  {
    "fchs","fabs","(bad)","(bad)","ftst","fxam","(bad)","(bad)",
  },

  /* d9_5  2 */
  {
    "fld1","fldl2t","fldl2e","fldpi","fldlg2","fldln2","fldz","(bad)",
  },

  /* d9_6  3 */
  {
    "f2xm1","fyl