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/* Instruction printing code for the AMD 29000

   Copyright (C) 1990, 93, 94, 95, 1998 Free Software Foundation, Inc.

   Contributed by Cygnus Support.  Written by Jim Kingdon.

This file is part of GDB.

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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "dis-asm.h"

#include "opcode/a29k.h"

/* Print a symbolic representation of a general-purpose

   register number NUM on STREAM.

   NUM is a number as found in the instruction, not as found in

   debugging symbols; it must be in the range 0-255.  */

static void

print_general (num, info)

     int num;

     struct disassemble_info *info;

{

  if (num < 128)

    (*info->fprintf_func) (info->stream, "gr%d", num);

  else

    (*info->fprintf_func) (info->stream, "lr%d", num - 128);

}

/* Like print_general but a special-purpose register.

   The mnemonics used by the AMD assembler are not quite the same

   as the ones in the User's Manual.  We use the ones that the

   assembler uses.  */

static void

print_special (num, info)

     unsigned int num;

     struct disassemble_info *info;

{

  /* Register names of registers 0-SPEC0_NUM-1.  */

  static char *spec0_names[] = {

    "vab", "ops", "cps", "cfg", "cha", "chd", "chc", "rbp", "tmc", "tmr",

    "pc0", "pc1", "pc2", "mmu", "lru", "rsn", "rma0", "rmc0", "rma1", "rmc1",

    "spc0", "spc1", "spc2", "iba0", "ibc0", "iba1", "ibc1", "dba", "dbc",

    "cir", "cdr"

    };

#define SPEC0_NUM ((sizeof spec0_names) / (sizeof spec0_names[0]))

  /* Register names of registers 128-128+SPEC128_NUM-1.  */

  static char *spec128_names[] = {

    "ipc", "ipa", "ipb", "q", "alu", "bp", "fc", "cr"

    };

#define SPEC128_NUM ((sizeof spec128_names) / (sizeof spec128_names[0]))

  /* Register names of registers 160-160+SPEC160_NUM-1.  */

  static char *spec160_names[] = {

    "fpe", "inte", "fps", "sr163", "exop"

    };

#define SPEC160_NUM ((sizeof spec160_names) / (sizeof spec160_names[0]))

  if (num < SPEC0_NUM)

    (*info->fprintf_func) (info->stream, spec0_names[num]);

  else if (num >= 128 && num < 128 + SPEC128_NUM)

    (*info->fprintf_func) (info->stream, spec128_names[num-128]);

  else if (num >= 160 && num < 160 + SPEC160_NUM)

    (*info->fprintf_func) (info->stream, spec160_names[num-160]);

  else

    (*info->fprintf_func) (info->stream, "sr%d", num);

}

/* Is an instruction with OPCODE a delayed branch?  */

static int

is_delayed_branch (opcode)

     int opcode;

{

  return (opcode == 0xa8 || opcode == 0xa9 || opcode == 0xa0 || opcode == 0xa1

          || opcode == 0xa4 || opcode == 0xa5

          || opcode == 0xb4 || opcode == 0xb5

          || opcode == 0xc4 || opcode == 0xc0

          || opcode == 0xac || opcode == 0xad

          || opcode == 0xcc);

}

/* Now find the four bytes of INSN and put them in *INSN{0,8,16,24}.  */

static void

find_bytes_big (insn, insn0, insn8, insn16, insn24)

     char *insn;

     unsigned char *insn0;

     unsigned char *insn8;

     unsigned char *insn16;

     unsigned char *insn24;

{

  *insn24 = insn[0];

  *insn16 = insn[1];

  *insn8  = insn[2];

  *insn0  = insn[3];

}

static void

find_bytes_little (insn, insn0, insn8, insn16, insn24)

     char *insn;

     unsigned char *insn0;

     unsigned char *insn8;

     unsigned char *insn16;

     unsigned char *insn24;

{

  *insn24 = insn[3];

  *insn16 = insn[2];

  *insn8 = insn[1];

  *insn0 = insn[0];

}

typedef void (*find_byte_func_type)

     PARAMS ((char *, unsigned char *, unsigned char *,

              unsigned char *, unsigned char *));

/* Print one instruction from MEMADDR on INFO->STREAM.

   Return the size of the instruction (always 4 on a29k).  */

static int

print_insn (memaddr, info)

     bfd_vma memaddr;

     struct disassemble_info *info;

{

  /* The raw instruction.  */

  char insn[4];

  /* The four bytes of the instruction.  */

  unsigned char insn24, insn16, insn8, insn0;

  find_byte_func_type find_byte_func = (find_byte_func_type)info->private_data;

  struct a29k_opcode CONST * opcode;

  {

    int status =

      (*info->read_memory_func) (memaddr, (bfd_byte *) &insn[0], 4, info);

    if (status != 0)

      {

        (*info->memory_error_func) (status, memaddr, info);

        return -1;

      }

  }

  (*find_byte_func) (insn, &insn0, &insn8, &insn16, &insn24);

  printf ("%02x%02x%02x%02x ", insn24, insn16, insn8, insn0);

  /* Handle the nop (aseq 0x40,gr1,gr1) specially */

  if ((insn24==0x70) && (insn16==0x40) && (insn8==0x01) && (insn0==0x01)) {

    (*info->fprintf_func) (info->stream,"nop");

    return 4;

  }

  /* The opcode is always in insn24.  */

  for (opcode = &a29k_opcodes[0];

       opcode < &a29k_opcodes[num_opcodes];

       ++opcode)

    {

      if (((unsigned long) insn24 << 24) == opcode->opcode)

        {

          char *s;

          (*info->fprintf_func) (info->stream, "%s ", opcode->name);

          for (s = opcode->args; *s != '\0'; ++s)

            {

              switch (*s)

                {

                case 'a':

                  print_general (insn8, info);

                  break;

                case 'b':

                  print_general (insn0, info);

                  break;

                case 'c':

                  print_general (insn16, info);

                  break;

                case 'i':

                  (*info->fprintf_func) (info->stream, "%d", insn0);

                  break;

                case 'x':

                  (*info->fprintf_func) (info->stream, "0x%x", (insn16 << 8) + insn0);

                  break;

                case 'h':

                  /* This used to be %x for binutils.  */

                  (*info->fprintf_func) (info->stream, "0x%x",

                                    (insn16 << 24) + (insn0 << 16));

                  break;

                case 'X':

                  (*info->fprintf_func) (info->stream, "%d",

                                    ((insn16 << 8) + insn0) | 0xffff0000);

                  break;

                case 'P':

                  /* This output looks just like absolute addressing, but

                     maybe that's OK (it's what the GDB m68k and EBMON

                     a29k disassemblers do).  */

                  /* All the shifting is to sign-extend it.  p*/

                  (*info->print_address_func)

                    (memaddr +

                     (((int)((insn16 << 10) + (insn0 << 2)) << 14) >> 14),

                     info);

                  break;

                case 'A':

                  (*info->print_address_func)

                    ((insn16 << 10) + (insn0 << 2), info);

                  break;

                case 'e':

                  (*info->fprintf_func) (info->stream, "%d", insn16 >> 7);

                  break;

                case 'n':

                  (*info->fprintf_func) (info->stream, "0x%x", insn16 & 0x7f);

                  break;

                case 'v':

                  (*info->fprintf_func) (info->stream, "0x%x", insn16);

                  break;

                case 's':

                  print_special (insn8, info);

                  break;

                case 'u':

                  (*info->fprintf_func) (info->stream, "%d", insn0 >> 7);

                  break;

                case 'r':

                  (*info->fprintf_func) (info->stream, "%d", (insn0 >> 4) & 7);

                  break;

                case 'I':

                  if ((insn16 & 3) != 0)

                    (*info->fprintf_func) (info->stream, "%d", insn16 & 3);

                  break;

                case 'd':

                  (*info->fprintf_func) (info->stream, "%d", (insn0 >> 2) & 3);

                  break;

                case 'f':

                  (*info->fprintf_func) (info->stream, "%d", insn0 & 3);

                  break;

                case 'F':

                  (*info->fprintf_func) (info->stream, "%d", (insn16 >> 2) & 15);

                  break;

                case 'C':

                  (*info->fprintf_func) (info->stream, "%d", insn16 & 3);

                  break;

                default:

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

                }

            }

          /* Now we look for a const,consth pair of instructions,

             in which case we try to print the symbolic address.  */

          if (insn24 == 2)  /* consth */

            {

              int errcode;

              char prev_insn[4];

              unsigned char prev_insn0, prev_insn8, prev_insn16, prev_insn24;

              errcode = (*info->read_memory_func) (memaddr - 4,

                                                   (bfd_byte *) &prev_insn[0],

                                                   4,

                                                   info);

              if (errcode == 0)

                {

                  /* If it is a delayed branch, we need to look at the

                     instruction before the delayed brach to handle

                     things like

                     const _foo

                     call _printf

                     consth _foo

                     */

                  (*find_byte_func) (prev_insn, &prev_insn0, &prev_insn8,

                                     &prev_insn16, &prev_insn24);

                  if (is_delayed_branch (prev_insn24))

                    {

                      errcode = (*info->read_memory_func)

                        (memaddr - 8, (bfd_byte *) &prev_insn[0], 4, info);

                      (*find_byte_func) (prev_insn, &prev_insn0, &prev_insn8,

                                         &prev_insn16, &prev_insn24);

                    }

                }

              /* If there was a problem reading memory, then assume

                 the previous instruction was not const.  */

              if (errcode == 0)

                {

                  /* Is it const to the same register?  */

                  if (prev_insn24 == 3

                      && prev_insn8 == insn8)

                    {

                      (*info->fprintf_func) (info->stream, "\t; ");

                      (*info->print_address_func)

                        (((insn16 << 24) + (insn0 << 16)

                          + (prev_insn16 << 8) + (prev_insn0)),

                         info);

                    }

                }

            }

          return 4;

        }

    }

  /* This used to be %8x for binutils.  */

  (*info->fprintf_func)

    (info->stream, ".word 0x%08x",

     (insn24 << 24) + (insn16 << 16) + (insn8 << 8) + insn0);

  return 4;

}

/* Disassemble an big-endian a29k instruction.  */

int

print_insn_big_a29k (memaddr, info)

     bfd_vma memaddr;

     struct disassemble_info *info;

{

  info->private_data = (PTR) find_bytes_big;

  return print_insn (memaddr, info);

}

/* Disassemble a little-endian a29k instruction.  */

int

print_insn_little_a29k (memaddr, info)

     bfd_vma memaddr;

     struct disassemble_info *info;

{

  info->private_data = (PTR) find_bytes_little;

  return print_insn (memaddr, info);

}