/* Disassemble z8000 code.
   Copyright 1992, 1993, 1998, 2000, 2001, 2002, 2003, 2005, 2007
   Free Software Foundation, Inc.

   This file is part of the GNU opcodes library.

   This library 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 3, or (at your option)
   any later version.

   It 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 file; see the file COPYING.  If not, write to the
   Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include "dis-asm.h"

#define DEFINE_TABLE
#include "z8k-opc.h"

#include <setjmp.h>

typedef struct
{
  /* These are all indexed by nibble number (i.e only every other entry
     of bytes is used, and every 4th entry of words).  */
  unsigned char nibbles[24];
  unsigned char bytes[24];
  unsigned short words[24];

  /* Nibble number of first word not yet fetched.  */
  int max_fetched;
  bfd_vma insn_start;
  jmp_buf bailout;

  int tabl_index;
  char instr_asmsrc[80];
  unsigned long arg_reg[0x0f];
  unsigned long immediate;
  unsigned long displacement;
  unsigned long address;
  unsigned long cond_code;
  unsigned long ctrl_code;
  unsigned long flags;
  unsigned long interrupts;
}
instr_data_s;

/* Make sure that bytes from INFO->PRIVATE_DATA->BUFFER (inclusive)
   to ADDR (exclusive) are valid.  Returns 1 for success, longjmps
   on error.  */
#define FETCH_DATA(info, nibble) \
  ((nibble) < ((instr_data_s *) (info->private_data))->max_fetched \
   ? 1 : fetch_data ((info), (nibble)))

static int
fetch_data (struct disassemble_info *info, int nibble)
{
  unsigned char mybuf[20];
  int status;
  instr_data_s *priv = (instr_data_s *) info->private_data;

  if ((nibble % 4) != 0)
    abort ();

  status = (*info->read_memory_func) (priv->insn_start,
				      (bfd_byte *) mybuf,
				      nibble / 2,
				      info);
  if (status != 0)
    {
      (*info->memory_error_func) (status, priv->insn_start, info);
      longjmp (priv->bailout, 1);
    }

  {
    int i;
    unsigned char *p = mybuf;

    for (i = 0; i < nibble;)
      {
	priv->words[i] = (p[0] << 8) | p[1];

	priv->bytes[i] = *p;
	priv->nibbles[i++] = *p >> 4;
	priv->nibbles[i++] = *p & 0xf;

	++p;
	priv->bytes[i] = *p;
	priv->nibbles[i++] = *p >> 4;
	priv->nibbles[i++] = *p & 0xf;

	++p;
      }
  }
  priv->max_fetched = nibble;
  return 1;
}

static char *codes[16] =
  {
    "f",
    "lt",
    "le",
    "ule",
    "ov/pe",
    "mi",
    "eq",
    "c/ult",
    "t",
    "ge",
    "gt",
    "ugt",
    "nov/po",
    "pl",
    "ne",
    "nc/uge"
  };

static char *ctrl_names[8] =
  {
    "<invld>",
    "flags",
    "fcw",
    "refresh",
    "psapseg",
    "psapoff",
    "nspseg",
    "nspoff"
  };

static int seg_length;
int z8k_lookup_instr (unsigned char *, disassemble_info *);
static void output_instr (instr_data_s *, unsigned long, disassemble_info *);
static void unpack_instr (instr_data_s *, int, disassemble_info *);
static void unparse_instr (instr_data_s *, int);

static int
print_insn_z8k (bfd_vma addr, disassemble_info *info, int is_segmented)
{
  instr_data_s instr_data;

  info->private_data = (PTR) &instr_data;
  instr_data.max_fetched = 0;
  instr_data.insn_start = addr;
  if (setjmp (instr_data.bailout) != 0)
    /* Error return.  */
    return -1;

  info->bytes_per_chunk = 2;
  info->bytes_per_line = 6;
  info->display_endian = BFD_ENDIAN_BIG;

  instr_data.tabl_index = z8k_lookup_instr (instr_data.nibbles, info);
  if (instr_data.tabl_index >= 0)
    {
      unpack_instr (&instr_data, is_segmented, info);
      unparse_instr (&instr_data, is_segmented);
      output_instr (&instr_data, addr, info);
      return z8k_table[instr_data.tabl_index].length + seg_length;
    }
  else
    {
      FETCH_DATA (info, 4);
      (*info->fprintf_func) (info->stream, ".word %02x%02x",
			     instr_data.bytes[0], instr_data.bytes[2]);
      return 2;
    }
}

int
print_insn_z8001 (bfd_vma addr, disassemble_info *info)
{
  return print_insn_z8k (addr, info, 1);
}

int
print_insn_z8002 (bfd_vma addr, disassemble_info *info)
{
  return print_insn_z8k (addr, info, 0);
}

int
z8k_lookup_instr (unsigned char *nibbles, disassemble_info *info)
{
  int nibl_index, tabl_index;
  int nibl_matched;
  int need_fetch = 0;
  unsigned short instr_nibl;
  unsigned short tabl_datum, datum_class, datum_value;

  nibl_matched = 0;
  tabl_index = 0;
  FETCH_DATA (info, 4);
  while (!nibl_matched && z8k_table[tabl_index].name)
    {
      nibl_matched = 1;
      for (nibl_index = 0;
	   nibl_index < z8k_table[tabl_index].length * 2 && nibl_matched;
	   nibl_index++)
	{
	  if ((nibl_index % 4) == 0)
            {
              /* Fetch data only if it isn't already there.  */
              if (nibl_index >= 4 || (nibl_index < 4 && need_fetch))
                FETCH_DATA (info, nibl_index + 4);   /* Fetch one word at a time.  */
              if (nibl_index < 4)
                need_fetch = 0;
              else
                need_fetch = 1;
            }
	  instr_nibl = nibbles[nibl_index];

	  tabl_datum = z8k_table[tabl_index].byte_info[nibl_index];
	  datum_class = tabl_datum & CLASS_MASK;
	  datum_value = ~CLASS_MASK & tabl_datum;

	  switch (datum_class)
	    {
	    case CLASS_BIT:
	      if (datum_value != instr_nibl)
		nibl_matched = 0;
	      break;
	    case CLASS_IGNORE:
	      break;
	    case CLASS_00II:
	      if (!((~instr_nibl) & 0x4))
		nibl_matched = 0;
	      break;
	    case CLASS_01II:
	      if (!(instr_nibl & 0x4))
		nibl_matched = 0;
	      break;
	    case CLASS_0CCC:
	      if (!((~instr_nibl) & 0x8))
		nibl_matched = 0;
	      break;
	    case CLASS_1CCC:
	      if (!(instr_nibl & 0x8))
		nibl_matched = 0;
	      break;
	    case CLASS_0DISP7:
	      if (!((~instr_nibl) & 0x8))
		nibl_matched = 0;
	      nibl_index += 1;
	      break;
	    case CLASS_1DISP7:
	      if (!(instr_nibl & 0x8))
		nibl_matched = 0;
	      nibl_index += 1;
	      break;
	    case CLASS_REGN0:
	      if (instr_nibl == 0)
		nibl_matched = 0;
	      break;
	    case CLASS_BIT_1OR2:
	      if ((instr_nibl | 0x2) != (datum_value | 0x2))
		nibl_matched = 0;
	      break;
	    default:
	      break;
	    }
	}

      if (nibl_matched)
	return tabl_index;

      tabl_index++;
    }
  return -1;
}

static void
output_instr (instr_data_s *instr_data,
              unsigned long addr ATTRIBUTE_UNUSED,
              disassemble_info *info)
{
  int num_bytes;
  char out_str[100];

  out_str[0] = 0;

  num_bytes = (z8k_table[instr_data->tabl_index].length + seg_length) * 2;
  FETCH_DATA (info, num_bytes);

  strcat (out_str, instr_data->instr_asmsrc);

  (*info->fprintf_func) (info->stream, "%s", out_str);
}

static void
unpack_instr (instr_data_s *instr_data, int is_segmented, disassemble_info *info)
{
  int nibl_count, loop;
  unsigned short instr_nibl, instr_byte, instr_word;
  long instr_long;
  unsigned int tabl_datum, datum_class;
  unsigned short datum_value;

  nibl_count = 0;
  loop = 0;
  seg_length = 0;

  while (z8k_table[instr_data->tabl_index].byte_info[loop] != 0)
    {
      FETCH_DATA (info, nibl_count + 4 - (nibl_count % 4));
      instr_nibl = instr_data->nibbles[nibl_count];
      instr_byte = instr_data->bytes[nibl_count & ~1];
      instr_word = instr_data->words[nibl_count & ~3];

      tabl_datum = z8k_table[instr_data->tabl_index].byte_info[loop];
      datum_class = tabl_datum & CLASS_MASK;
      datum_value = tabl_datum & ~CLASS_MASK;

      switch (datum_class)
	{
	case CLASS_DISP:
	  switch (datum_value)
	    {
	    case ARG_DISP16:
	      instr_data->displacement = instr_data->insn_start + 4
		+ (signed short) (instr_word & 0xffff);
	      nibl_count += 3;
	      break;
	    case ARG_DISP12:
	      if (instr_word & 0x800)
		/* Negative 12 bit displacement.  */
		instr_data->displacement = instr_data->insn_start + 2
		  - (signed short) ((instr_word & 0xfff) | 0xf000) * 2;
	      else
		instr_data->displacement = instr_data->insn_start + 2
		  - (instr_word & 0x0fff) * 2;

	      nibl_count += 2;
	      break;
	    default:
	      break;
	    }
	  break;
	case CLASS_IMM:
	  switch (datum_value)
	    {
	    case ARG_IMM4:
	      instr_data->immediate = instr_nibl;
	      break;
	    case ARG_NIM4:
	      instr_data->immediate = (- instr_nibl) & 0xf;
	      break;
	    case ARG_NIM8:
	      instr_data->immediate = (- instr_byte) & 0xff;
	      nibl_count += 1;
	      break;
	    case ARG_IMM8:
	      instr_data->immediate = instr_byte;
	      nibl_count += 1;
	      break;
	    case ARG_IMM16:
	      instr_data->immediate = instr_word;
	      nibl_count += 3;
	      break;
	    case ARG_IMM32:
	      FETCH_DATA (info, nibl_count + 8);
	      instr_long = (instr_data->words[nibl_count] << 16)
		| (instr_data->words[nibl_count + 4]);
	      instr_data->immediate = instr_long;
	      nibl_count += 7;
	      break;
	    case ARG_IMMN:
	      instr_data->immediate = instr_nibl - 1;
	      break;
	    case ARG_IMM4M1:
	      instr_data->immediate = instr_nibl + 1;
	      break;
	    case ARG_IMM_1:
	      instr_data->immediate = 1;
	      break;
	    case ARG_IMM_2:
	      instr_data->immediate = 2;
	      break;
	    case ARG_IMM2:
	      instr_data->immediate = instr_nibl & 0x3;
	      break;
	    default:
	      break;
	    }
	  break;
	case CLASS_CC:
	  instr_data->cond_code = instr_nibl;
	  break;
	case CLASS_ADDRESS:
	  if (is_segmented)
	    {
	      if (instr_nibl & 0x8)
		{
		  FETCH_DATA (info, nibl_count + 8);
		  instr_long = (instr_data->words[nibl_count] << 16)
		    | (instr_data->words[nibl_count + 4]);
		  instr_data->address = ((instr_word & 0x7f00) << 16)
		    + (instr_long & 0xffff);
		  nibl_count += 7;
		  seg_length = 2;
		}
	      else
		{
		  instr_data->address = ((instr_word & 0x7f00) << 16)
		    + (instr_word & 0x00ff);
		  nibl_count += 3;
		}
	    }
	  else
	    {
	      instr_data->address = instr_word;
	      nibl_count += 3;
	    }
	  break;
	case CLASS_0CCC:
	case CLASS_1CCC:
	  instr_data->ctrl_code = instr_nibl & 0x7;
	  break;
	case CLASS_0DISP7:
	  instr_data->displacement =
	    instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
	  nibl_count += 1;
	  break;
	case CLASS_1DISP7:
	  instr_data->displacement =
	    instr_data->insn_start + 2 - (instr_byte & 0x7f) * 2;
	  nibl_count += 1;
	  break;
	case CLASS_01II:
	  instr_data->interrupts = instr_nibl & 0x3;
	  break;
	case CLASS_00II:
	  instr_data->interrupts = instr_nibl & 0x3;
	  break;
	case CLASS_IGNORE:
	case CLASS_BIT:
	  instr_data->ctrl_code = instr_nibl & 0x7;
	  break;
	case CLASS_FLAGS:
	  instr_data->flags = instr_nibl;
	  break;
	case CLASS_REG:
	  instr_data->arg_reg[datum_value] = instr_nibl;
	  break;
	case CLASS_REGN0:
	  instr_data->arg_reg[datum_value] = instr_nibl;
	  break;
	case CLASS_DISP8:
	  instr_data->displacement =
	    instr_data->insn_start + 2 + (signed char) instr_byte * 2;
	  nibl_count += 1;
	  break;
        case CLASS_BIT_1OR2:
          instr_data->immediate = ((instr_nibl >> 1) & 0x1) + 1;
          nibl_count += 1;
	  break;
	default:
	  abort ();
	  break;
	}

      loop += 1;
      nibl_count += 1;
    }
}

static void
print_intr(char *tmp_str, unsigned long interrupts)
{
  int comma = 0;

  *tmp_str = 0;
  if (! (interrupts & 2))
    {
      strcat (tmp_str, "vi");
      comma = 1;
    }
  if (! (interrupts & 1))
    {
      if (comma) strcat (tmp_str, ",");
      strcat (tmp_str, "nvi");
    }
}

static void
print_flags(char *tmp_str, unsigned long flags)
{
  int comma = 0;

  *tmp_str = 0;
  if (flags & 8)
    {
      strcat (tmp_str, "c");
      comma = 1;
    }
  if (flags & 4)
    {
      if (comma) strcat (tmp_str, ",");
      strcat (tmp_str, "z");
      comma = 1;
    }
  if (flags & 2)
    {
      if (comma) strcat (tmp_str, ",");
      strcat (tmp_str, "s");
      comma = 1;
    }
  if (flags & 1)
    {
      if (comma) strcat (tmp_str, ",");
      strcat (tmp_str, "p");
    }
}

static void
unparse_instr (instr_data_s *instr_data, int is_segmented)
{
  unsigned short datum_value;
  unsigned int tabl_datum, datum_class;
  int loop, loop_limit;
  char out_str[80], tmp_str[25];

  sprintf (out_str, "%s\t", z8k_table[instr_data->tabl_index].name);

  loop_limit = z8k_table[instr_data->tabl_index].noperands;
  for (loop = 0; loop < loop_limit; loop++)
    {
      if (loop)
	strcat (out_str, ",");

      tabl_datum = z8k_table[instr_data->tabl_index].arg_info[loop];
      datum_class = tabl_datum & CLASS_MASK;
      datum_value = tabl_datum & ~CLASS_MASK;

      switch (datum_class)
	{
	case CLASS_X:
          sprintf (tmp_str, "0x%0lx(r%ld)", instr_data->address,
                   instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_BA:
          if (is_segmented)
            sprintf (tmp_str, "rr%ld(#0x%lx)", instr_data->arg_reg[datum_value],
                     instr_data->immediate);
          else
            sprintf (tmp_str, "r%ld(#0x%lx)", instr_data->arg_reg[datum_value],
                     instr_data->immediate);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_BX:
          if (is_segmented)
            sprintf (tmp_str, "rr%ld(r%ld)", instr_data->arg_reg[datum_value],
                     instr_data->arg_reg[ARG_RX]);
          else
            sprintf (tmp_str, "r%ld(r%ld)", instr_data->arg_reg[datum_value],
                     instr_data->arg_reg[ARG_RX]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_DISP:
	  sprintf (tmp_str, "0x%0lx", instr_data->displacement);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_IMM:
	  if (datum_value == ARG_IMM2)	/* True with EI/DI instructions only.  */
	    {
	      print_intr (tmp_str, instr_data->interrupts);
	      strcat (out_str, tmp_str);
	      break;
	    }
	  sprintf (tmp_str, "#0x%0lx", instr_data->immediate);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_CC:
	  sprintf (tmp_str, "%s", codes[instr_data->cond_code]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_CTRL:
	  sprintf (tmp_str, "%s", ctrl_names[instr_data->ctrl_code]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_DA:
	case CLASS_ADDRESS:
	  sprintf (tmp_str, "0x%0lx", instr_data->address);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_IR:
	  if (is_segmented)
	    sprintf (tmp_str, "@rr%ld", instr_data->arg_reg[datum_value]);
	  else
	    sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_IRO:
          sprintf (tmp_str, "@r%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_FLAGS:
	  print_flags(tmp_str, instr_data->flags);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_REG_BYTE:
	  if (instr_data->arg_reg[datum_value] >= 0x8)
	    sprintf (tmp_str, "rl%ld",
		     instr_data->arg_reg[datum_value] - 0x8);
	  else
	    sprintf (tmp_str, "rh%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_REG_WORD:
	  sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_REG_QUAD:
	  sprintf (tmp_str, "rq%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_REG_LONG:
	  sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	case CLASS_PR:
	  if (is_segmented)
	    sprintf (tmp_str, "rr%ld", instr_data->arg_reg[datum_value]);
	  else
	    sprintf (tmp_str, "r%ld", instr_data->arg_reg[datum_value]);
	  strcat (out_str, tmp_str);
	  break;
	default:
	  abort ();
	  break;
	}
    }

  strcpy (instr_data->instr_asmsrc, out_str);
}