binutils-gdb/opcodes/d10v-dis.c

/* Disassemble D10V instructions.
   Copyright (C) 1996, 1997 Free Software Foundation, Inc.

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 <stdio.h>

#include "opcode/d10v.h" 
#include "dis-asm.h"

/* the PC wraps at 18 bits, except for the segment number */
/* so use this mask to keep the parts we want */
#define PC_MASK	0x03003FFF

static void dis_2_short PARAMS ((unsigned long insn, bfd_vma memaddr, 
				 struct disassemble_info *info, int order));
static void dis_long PARAMS ((unsigned long insn, bfd_vma memaddr, 
			      struct disassemble_info *info));

int 
print_insn_d10v (memaddr, info)
     bfd_vma memaddr;
     struct disassemble_info *info;
{
  int status;
  bfd_byte buffer[4];
  unsigned long insn;

  status = (*info->read_memory_func) (memaddr, buffer, 4, info);
  if (status != 0)
    {
      (*info->memory_error_func) (status, memaddr, info);
      return -1;
    }
  insn = bfd_getb32 (buffer);

  status = insn & FM11;
  switch (status) {
  case 0:
    dis_2_short (insn, memaddr, info, 2);
    break;
  case FM01:
    dis_2_short (insn, memaddr, info, 0);
    break;
  case FM10:
    dis_2_short (insn, memaddr, info, 1);
    break;
  case FM11:
    dis_long (insn, memaddr, info);
    break;
  }
  return 4;
}

static void
print_operand (oper, insn, op, memaddr, info)
     struct d10v_operand *oper;
     unsigned long insn;
     struct d10v_opcode *op;
     bfd_vma memaddr;
     struct disassemble_info *info;
{
  int num, shift;

  if (oper->flags == OPERAND_ATMINUS)
    {
      (*info->fprintf_func) (info->stream, "@-");   
      return;
    }
  if (oper->flags == OPERAND_MINUS)
    {
      (*info->fprintf_func) (info->stream, "-");   
      return;
    }
  if (oper->flags == OPERAND_PLUS)
    {
      (*info->fprintf_func) (info->stream, "+");   
      return;
    }
  if (oper->flags == OPERAND_ATSIGN)
    {
      (*info->fprintf_func) (info->stream, "@");   
      return;
    }
  if (oper->flags == OPERAND_ATPAR)
    {
      (*info->fprintf_func) (info->stream, "@(");   
      return;
    }

  shift = oper->shift;

  /* the LONG_L format shifts registers over by 15 */
  if (op->format == LONG_L && (oper->flags & OPERAND_REG))
    shift += 15;

  num = (insn >> shift) & (0x7FFFFFFF >> (31 - oper->bits));

  if (oper->flags & OPERAND_REG)
    {
      int i;
      int match=0;
      num += oper->flags & (OPERAND_ACC|OPERAND_FLAG|OPERAND_CONTROL);
      for (i=0;i<reg_name_cnt();i++)
	{
	  if (num == pre_defined_registers[i].value)
	    {
	      if (pre_defined_registers[i].pname)
		(*info->fprintf_func) (info->stream, "%s",pre_defined_registers[i].pname);
	      else
		(*info->fprintf_func) (info->stream, "%s",pre_defined_registers[i].name);
	      match=1;
	      break;
	    }
	}
      if (match==0)
	{
	  /* this would only get executed if a register was not in the 
	     register table */
	  if (oper->flags & OPERAND_ACC)
	    (*info->fprintf_func) (info->stream, "a");
	  else if (oper->flags & OPERAND_CONTROL)
	    (*info->fprintf_func) (info->stream, "cr");
	  else if(oper->flags & OPERAND_REG)
	    (*info->fprintf_func) (info->stream, "r");
	  (*info->fprintf_func) (info->stream, "%d",num);
	}
    }
  else
    {
      /* addresses are right-shifted by 2 */
      if (oper->flags & OPERAND_ADDR)
	{
	  long max;
	  int neg=0;
	  max = (1 << (oper->bits - 1));
	  if (num & max)
	    {
	      num = -num & ((1 << oper->bits)-1);
	      neg = 1;
	    }
	  num = num<<2;
	  if (neg)
	    (*info->print_address_func) ((memaddr - num) & PC_MASK, info);
	  else
	    (*info->print_address_func) ((memaddr + num) & PC_MASK, info);
	}
      else
	{
	  if (oper->flags & OPERAND_SIGNED)
	    {
	      int max = (1 << (oper->bits - 1));
	      if (num & max)
		{
		  num = -num & ((1 << oper->bits)-1);
		  (*info->fprintf_func) (info->stream, "-");
		}
	    }
	  (*info->fprintf_func) (info->stream, "0x%x",num);
	}
    }
}


static void
dis_long (insn, memaddr, info)
     unsigned long insn;
     bfd_vma memaddr;
     struct disassemble_info *info;
{
  int i;
  char buf[32];
  struct d10v_opcode *op = (struct d10v_opcode *)d10v_opcodes;
  struct d10v_operand *oper;
  int need_paren = 0;
  int match = 0;

  while (op->name)
    {
      if ((op->format & LONG_OPCODE) && ((op->mask & insn) == op->opcode))
	{
	  match = 1;
	  (*info->fprintf_func) (info->stream, "%s\t", op->name);   
	  for ( i=0; op->operands[i]; i++)
	    {
	      oper = (struct d10v_operand *)&d10v_operands[op->operands[i]];
	      if (oper->flags == OPERAND_ATPAR)
		need_paren = 1;
	      print_operand (oper, insn, op, memaddr, info);
	      if (op->operands[i+1] && oper->bits &&
		  d10v_operands[op->operands[i+1]].flags != OPERAND_PLUS &&
		  d10v_operands[op->operands[i+1]].flags != OPERAND_MINUS)
		(*info->fprintf_func) (info->stream, ", ");   
	    }
	  break;
	}
      op++;
    }

  if (!match)
    (*info->fprintf_func) (info->stream, ".long\t0x%08x",insn);   

  if (need_paren)
    (*info->fprintf_func) (info->stream, ")");   
}

static void
dis_2_short (insn, memaddr, info, order)
     unsigned long insn;
     bfd_vma memaddr;
     struct disassemble_info *info;
     int order;
{
  int i,j;
  char astr[2][32];
  unsigned int ins[2];
  struct d10v_opcode *op;
  char buf[32];
  int match, num_match=0;
  struct d10v_operand *oper;
  int need_paren = 0;

  ins[0] = (insn & 0x3FFFFFFF) >> 15;
  ins[1] = insn & 0x00007FFF;

  for(j=0;j<2;j++)
    {
      op = (struct d10v_opcode *)d10v_opcodes;
      match=0;
      while (op->name)
	{
	  if ((op->format & SHORT_OPCODE) && ((op->mask & ins[j]) == op->opcode))
	    {
	      (*info->fprintf_func) (info->stream, "%s\t",op->name);   
	      for (i=0; op->operands[i]; i++)
		{
		  oper = (struct d10v_operand *)&d10v_operands[op->operands[i]];
		  if (oper->flags == OPERAND_ATPAR)
		    need_paren = 1;
		  print_operand (oper, ins[j], op, memaddr, info);
		  if (op->operands[i+1] && oper->bits && 
		  d10v_operands[op->operands[i+1]].flags != OPERAND_PLUS &&
		  d10v_operands[op->operands[i+1]].flags != OPERAND_MINUS)
		    (*info->fprintf_func) (info->stream, ", ");   
		}
	      match = 1;
	      num_match++;
	      break;
	    }
	  op++;
	}
      if (!match)
	(*info->fprintf_func) (info->stream, "unknown");   

      switch (order)
	{
	case 0:
	  (*info->fprintf_func) (info->stream, "\t->\t");   
	  order = -1;
	  break;
	case 1:
	  (*info->fprintf_func) (info->stream, "\t<-\t");   
	  order = -1;
	  break;
	case 2:
	  (*info->fprintf_func) (info->stream, "\t||\t");   
	  order = -1;
	  break;
	default:
	  break;
	}
    }

  if (num_match == 0)
    (*info->fprintf_func) (info->stream, ".long\t0x%08x",insn);   

  if (need_paren)
    (*info->fprintf_func) (info->stream, ")");   
}