darling-gdb/opcodes/d30v-dis.c

/* Disassemble D30V instructions.
   Copyright (C) 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/d30v.h" 
#include "dis-asm.h"

#define PC_MASK 0xFFFFFFFF

static int lookup_opcode PARAMS (( struct d30v_insn *insn, long num, int is_long ));
static void print_insn PARAMS (( struct disassemble_info *info, bfd_vma memaddr, long long num, 
				 struct d30v_insn *insn, int is_long ));
static int extract_value PARAMS (( long long num, struct d30v_operand *oper, int is_long ));

int 
print_insn_d30v (memaddr, info)
     bfd_vma memaddr;
     struct disassemble_info *info;
{
  int status, i;
  bfd_byte buffer[12];
  unsigned long in1,in2;
  struct d30v_insn insn;
  long long num;

  insn.form = (struct d30v_format *)NULL;

  status = (*info->read_memory_func) (memaddr, buffer, 8, info);
  if (status != 0)
    {
      (*info->memory_error_func) (status, memaddr, info);
      return -1;
    }
  info->bytes_per_line = 8;
  info->bytes_per_chunk = 4;
  info->display_endian = BFD_ENDIAN_BIG;
  in1 = bfd_getb32 (buffer);
  in2 = bfd_getb32 (buffer+4);
  
  if (in1 & in2 & FM01)
    {
      /* LONG instruction */
      if (!lookup_opcode(&insn, in1, 1))
	{
	  (*info->fprintf_func) (info->stream, ".long\t0x%x,0x%x",in1,in2);
	  return 8;
	}
      num = (long long)in1 << 32 | in2;
      print_insn(info, memaddr, num, &insn, 1);
    }
  else
    {
      num = in1;
      if (!lookup_opcode(&insn, in1, 0))
	(*info->fprintf_func) (info->stream, ".long\t0x%x",in1);
      else
	print_insn(info, memaddr, num, &insn, 0);
      
      switch ( ((in1>>31)<<1) | (in2>>31) )
	{
	case 0:
	  (*info->fprintf_func) (info->stream, "\t||\t");   
	  break;
	case 1:
	  (*info->fprintf_func) (info->stream, "\t->\t");   
	  break;
	case 2:
	  (*info->fprintf_func) (info->stream, "\t<-\t");   
	default:
	  break;
	}
      
      insn.form = (struct d30v_format *)NULL;
      num = in2;
      if (!lookup_opcode(&insn, in2, 0))
	(*info->fprintf_func) (info->stream, ".long\t0x%x",in2);
      else
	print_insn(info, memaddr, num, &insn, 0);

    }
  return 8;
}


static int
lookup_opcode (insn, num, is_long)
     struct d30v_insn *insn;
     long num;
     int is_long;
{
  int i=0, index;
  struct d30v_format *f;
  struct d30v_opcode *op = (struct d30v_opcode *)d30v_opcode_table;
  int op1 = (num >> 25) & 0x7;
  int op2 = (num >> 20) & 0x1f;
  int mod = (num >> 18) & 0x3;

  /* find the opcode */
  do {
    if ((op->op1 == op1) && (op->op2 == op2))
      break;
    op++;
  } while (op->name);

  if (!op || !op->name)
    return 0;

  while (op->op1 == op1 && op->op2 == op2)
    {
      /* scan through all the formats for the opcode  */
      while (index = op->format[i++])
	{
	  f = (struct d30v_format *)&d30v_format_table[index];
	  while (f->form == index)
	    {
	      if ((!is_long || f->form >= LONG) && (f->modifier == mod))
		{
		  insn->form = f;
		  break;
		}
	      f++;
	    }
	  if (insn->form)
	    break;
	}
      if (insn->form)
	break;
      op++;
      i=0;
    }
  if (insn->form == NULL)
    return 0;

  insn->op = op;
  insn->ecc = (num >> 28) & 0x7;
  return 1;
}


static void 
print_insn ( info, memaddr, num, insn, is_long )
     struct disassemble_info *info;
     bfd_vma memaddr;
     long long num;
     struct d30v_insn *insn;
     int is_long;
{
  char buffer[128];
  int val, opnum, need_comma=0;
  struct d30v_operand *oper;
  int i, match, opind=0, need_paren=0, found_control=0;

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

  /* check for CMP or CMPU */
  if (d30v_operand_table[insn->form->operands[0]].flags & OPERAND_NAME)
    {
      opind++;
      val = extract_value(num,(struct d30v_operand *)&d30v_operand_table[insn->form->operands[0]],is_long);
      (*info->fprintf_func) (info->stream, "%s",d30v_cc_names[val]);
    }

  if (insn->ecc)
    (*info->fprintf_func) (info->stream, "/%s",d30v_ecc_names[insn->ecc]);

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

  while (opnum = insn->form->operands[opind++])
    {
      oper = (struct d30v_operand *)&d30v_operand_table[opnum];

      if (need_comma && oper->flags != OPERAND_PLUS && oper->flags != OPERAND_MINUS)
	{
	  need_comma=0;
	  (*info->fprintf_func) (info->stream, ", ");
	}

      if (oper->flags == OPERAND_ATMINUS)
	{
	  (*info->fprintf_func) (info->stream, "@-");
	  continue;
	}
      if (oper->flags == OPERAND_MINUS)
	{
	  (*info->fprintf_func) (info->stream, "-");   
	  continue;
	}
      if (oper->flags == OPERAND_PLUS)
	{
	  (*info->fprintf_func) (info->stream, "+");   
	  continue;
	}
      if (oper->flags == OPERAND_ATSIGN)
	{
	  (*info->fprintf_func) (info->stream, "@");   
	  continue;
	}
      if (oper->flags == OPERAND_ATPAR)
	{
	  (*info->fprintf_func) (info->stream, "@(");   
	  need_paren = 1;
	  continue;
	}

      if (oper->flags == OPERAND_SPECIAL)
	continue;

      val = extract_value(num, oper, is_long);
      
      if (oper->flags & OPERAND_REG)
	{
	  match = 0;
	  if (oper->flags & OPERAND_CONTROL)
	    {
	      struct d30v_operand *oper3 = 
		(struct d30v_operand *)&d30v_operand_table[insn->form->operands[2]];	      
	      int id = extract_value (num, oper3, is_long );
	      found_control = 1;
	      switch ( id )
		{
		case 0:
		  val |= OPERAND_CONTROL;
		  break;
		case 1:
		case 2:
		  val = OPERAND_CONTROL + MAX_CONTROL_REG + id;
		  break;
		case 3:
		  val |= OPERAND_FLAG;
		  break;
		default:
		  fprintf(stderr,"illegal id (%d)\n",id);
		}
	    }
	  else if (oper->flags & OPERAND_ACC)
	    val |= OPERAND_ACC;
	  else if (oper->flags & OPERAND_FLAG)
	    val |= OPERAND_FLAG;
	  for (i=0;i<reg_name_cnt();i++)
	    {
	      if (val == 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 */
	      (*info->fprintf_func) (info->stream, "<unknown register %d>",val & 0x3F);	      
	    }
	}
      else if (insn->op->reloc_flag == RELOC_PCREL)
	{
	  long max;
	  int neg=0;
	  max = (1 << (oper->bits - 1));
	  if (val & max)
	    {
	      if (oper->bits == 32)
		val = -val;
	      else
		val = -val & ((1 << oper->bits)-1);
	      neg = 1;
	    }
	  if (neg)
	    (*info->print_address_func) ((memaddr - val) & PC_MASK, info);
	  else
	    (*info->print_address_func) ((memaddr + val) & PC_MASK, info);
	}
      else if (insn->op->reloc_flag == RELOC_ABS)
	{
	  (*info->print_address_func) (val, info);
	}
      else
	{
	  if (oper->flags & OPERAND_SIGNED)
	    {
	      int max = (1 << (oper->bits - 1));
	      if (val & max)
		{
		  val = -val & ((1 << oper->bits) - 1);
		  (*info->fprintf_func) (info->stream, "-");
		}
	    }
	  (*info->fprintf_func) (info->stream, "0x%x",val);
	}
      /* if there is another operand, then write a comma and space */
      if (insn->form->operands[opind] && !(found_control && opind == 2))
	need_comma = 1;
    }
  if (need_paren)
    (*info->fprintf_func) (info->stream, ")");
}



static int
extract_value (num, oper, is_long)
     long long num;
     struct d30v_operand *oper;
     int is_long;
{
  int val;
  int shift = 12 - oper->position;
  int mask = (0xFFFFFFFF >> (32 - oper->bits));

  if (is_long)
    {
      if (oper->bits == 32) 
	{
	  /* piece together 32-bit constant */
	  val = num & 0x3FFFF | (num & 0xFF00000) >> 2 |
	    (num & 0x3F00000000LL) >> 6;
	}
      else	
	val = (num >> (32 + shift)) & mask;	
    }
  else
    val = (num >> shift) & mask;

  if (oper->flags & OPERAND_SHIFT)
    val <<= 3;

  return val;
}