/* Disassemble z8000 code.

   Copyright (C) 1992-2023 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 "disassemble.h"

#include "libiberty.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.  */

  unsigned int max_fetched;

  bfd_vma insn_start;

  OPCODES_SIGJMP_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);

      OPCODES_SIGLONGJMP (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 = &instr_data;

  instr_data.max_fetched = 0;

  instr_data.insn_start = addr;

  if (OPCODES_SIGSETJMP (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)

{

  unsigned 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_matched

       && nibl_index < ARRAY_SIZE (z8k_table[0].byte_info)

       && nibl_index < z8k_table[tabl_index].length * 2;

     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)

{

  unsigned 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)

{

  unsigned 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 = ((unsigned) 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 = ((unsigned) 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);

}