[deliverable/binutils-gdb.git] / opcodes / pdp11-dis.c

/* Print DEC PDP-11 instructions.
   Copyright 2001 Free Software Foundation, Inc.

This file 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 "sysdep.h"
#include "dis-asm.h"
#include "opcode/pdp11.h"

#define AFTER_INSTRUCTION	"\t"
#define OPERAND_SEPARATOR	", "

#define JUMP	0x1000	/* flag that this operand is used in a jump */

#define FPRINTF	(*info->fprintf_func)
#define F	info->stream

/* sign-extend a 16-bit number in an int */
#define SIGN_BITS	(8 * sizeof (int) - 16)
#define sign_extend(x) (((x) << SIGN_BITS) >> SIGN_BITS)

static int read_word PARAMS ((bfd_vma memaddr, int *word,
			      disassemble_info *info));
static void print_signed_octal PARAMS ((int n, disassemble_info *info));
static void print_reg PARAMS ((int reg, disassemble_info *info));
static void print_freg PARAMS ((int freg, disassemble_info *info));
static int print_operand PARAMS ((bfd_vma *memaddr, int code,
				  disassemble_info *info));
int print_insn_pdp11 PARAMS ((bfd_vma memaddr, disassemble_info *info));

static int
read_word (memaddr, word, info)
     bfd_vma memaddr;
     int *word;
     disassemble_info *info;
{
  int status;
  bfd_byte x[2];

  status = (*info->read_memory_func) (memaddr, x, 2, info);
  if (status != 0)
    return -1;

  *word = x[1] << 8 | x[0];
  return 0;
}

static void
print_signed_octal (n, info)
     int n;
     disassemble_info *info;
{
  if (n < 0)
    FPRINTF (F, "-%o", -n);
  else
    FPRINTF (F, "%o", n);
}

static void
print_reg (reg, info)
     int reg;
     disassemble_info *info;
{
  /* mask off the addressing mode, if any */
  reg &= 7;

  switch (reg)
    {
    case 0: case 1: case 2: case 3: case 4: case 5:
		FPRINTF (F, "r%d", reg); break;
    case 6:	FPRINTF (F, "sp"); break;
    case 7:	FPRINTF (F, "pc"); break;
    default:	/* error */
    }
}

static void
print_freg (freg, info)
     int freg;
     disassemble_info *info;
{
  FPRINTF (F, "fr%d", freg);
}

static int
print_operand (memaddr, code, info)
     bfd_vma *memaddr;
     int code;
     disassemble_info *info;
{
  int mode = (code >> 3) & 7;
  int reg = code & 7;
  int disp;

  switch (mode)
    {
    case 0:
      print_reg (reg, info);
      break;
    case 1:
      FPRINTF (F, "(");
      print_reg (reg, info);
      FPRINTF (F, ")");
      break;
    case 2:
      if (reg == 7)
	{
	  int data;
	  if (read_word (*memaddr, &data, info) < 0)
	    return -1;
	  FPRINTF (F, "$");
	  print_signed_octal (sign_extend (data), info);
	  *memaddr += 2;
	}
      else
	{
	  FPRINTF (F, "(");
	  print_reg (reg, info);
	  FPRINTF (F, ")+");
	}
	break;
    case 3:
      if (reg == 7)
	{
	  int address;
	  if (read_word (*memaddr, &address, info) < 0)
	    return -1;
	  FPRINTF (F, "*$%o", address);
	  *memaddr += 2;
	}
      else
	{
	  FPRINTF (F, "*(");
	  print_reg (reg, info);
	  FPRINTF (F, ")+");
	}
	break;
    case 4:
      FPRINTF (F, "-(");
      print_reg (reg, info);
      FPRINTF (F, ")");
      break;
    case 5:
      FPRINTF (F, "*-(");
      print_reg (reg, info);
      FPRINTF (F, ")");
      break;
    case 6:
    case 7:
      if (read_word (*memaddr, &disp, info) < 0)
	return -1;
      *memaddr += 2;
      if (reg == 7)
	{
	  bfd_vma address = *memaddr + sign_extend (disp);
	  if (!(code & JUMP))
	    FPRINTF (F, "*$");
	  (*info->print_address_func) (address, info);
	}
      else
	{
	  if (mode == 7)
	    FPRINTF (F, "*");
	  print_signed_octal (sign_extend (disp), info);
	  FPRINTF (F, "(");
	  print_reg (reg, info);
	  FPRINTF (F, ")");
	}
      break;
    }

  return 0;
}

/* Print the PDP-11 instruction at address MEMADDR in debugged memory,
   on INFO->STREAM.  Returns length of the instruction, in bytes.  */

int
print_insn_pdp11 (memaddr, info)
     bfd_vma memaddr;
     disassemble_info *info;
{
  bfd_vma start_memaddr = memaddr;
  int opcode;
  int src, dst;
  int i;

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

  if (read_word (memaddr, &opcode, info) != 0)
    return -1;
  memaddr += 2;

  src = (opcode >> 6) & 0x3f;
  dst = opcode & 0x3f;

  for (i = 0; i < pdp11_num_opcodes; i++)
    {
#define OP pdp11_opcodes[i]
      if ((opcode & OP.mask) == OP.opcode)
	switch (OP.type)
	  {
	  case PDP11_OPCODE_NO_OPS:
	    FPRINTF (F, OP.name);
	    goto done;
	  case PDP11_OPCODE_REG:
	    FPRINTF (F, OP.name);
	    FPRINTF (F, AFTER_INSTRUCTION);
	    print_reg (dst, info);
	    goto done;
	  case PDP11_OPCODE_OP:
	    FPRINTF (F, OP.name);
	    FPRINTF (F, AFTER_INSTRUCTION);
	    if (strcmp (OP.name, "jmp") == 0)
	      dst |= JUMP;
	    if (print_operand (&memaddr, dst, info) < 0)
	      return -1;
	    goto done;
	  case PDP11_OPCODE_REG_OP:
	    FPRINTF (F, OP.name);
	    FPRINTF (F, AFTER_INSTRUCTION);
	    print_reg (src, info);
	    FPRINTF (F, OPERAND_SEPARATOR);
	    if (strcmp (OP.name, "jsr") == 0)
	      dst |= JUMP;
	    if (print_operand (&memaddr, dst, info) < 0)
	      return -1;
	    goto done;
	  case PDP11_OPCODE_REG_OP_REV:
	    FPRINTF (F, OP.name);
	    FPRINTF (F, AFTER_INSTRUCTION);
	    if (print_operand (&memaddr, dst, info) < 0)
	      return -1;
	    FPRINTF (F, OPERAND_SEPARATOR);
	    print_reg (src, info);
	    goto done;
	  case PDP11_OPCODE_AC_OP:
	    {
	      int ac = (opcode & 0xe0) >> 6;
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      print_freg (ac, info);
	      FPRINTF (F, OPERAND_SEPARATOR);
	      if (print_operand (&memaddr, dst, info) < 0)
		return -1;
	      goto done;
	    }
	  case PDP11_OPCODE_OP_OP:
	    FPRINTF (F, OP.name);
	    FPRINTF (F, AFTER_INSTRUCTION);
	    if (print_operand (&memaddr, src, info) < 0)
	      return -1;
	    FPRINTF (F, OPERAND_SEPARATOR);
	    if (print_operand (&memaddr, dst, info) < 0)
	      return -1;
	    goto done;
	  case PDP11_OPCODE_DISPL:
	    {
	      int displ = (opcode & 0xff) << 8;
	      bfd_vma address = memaddr + (sign_extend (displ) >> 7);
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      (*info->print_address_func) (address, info);
	      goto done;
	    }
	  case PDP11_OPCODE_REG_DISPL:
	    {
	      int displ = (opcode & 0x3f) << 10;
	      bfd_vma address = memaddr + (sign_extend (displ) >> 9);
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      print_reg (src, info);
	      FPRINTF (F, OPERAND_SEPARATOR);
	      (*info->print_address_func) (address, info);
	      goto done;
	    }
	  case PDP11_OPCODE_IMM8:
	    {
	      int code = opcode & 0xff;
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      FPRINTF (F, "%o", code);
	      goto done;
	    }
	  case PDP11_OPCODE_IMM6:
	    {
	      int code = opcode & 0x3f;
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      FPRINTF (F, "%o", code);
	      goto done;
	    }
	  case PDP11_OPCODE_IMM3:
	    {
	      int code = opcode & 7;
	      FPRINTF (F, OP.name);
	      FPRINTF (F, AFTER_INSTRUCTION);
	      FPRINTF (F, "%o", code);
	      goto done;
	    }
	  case PDP11_OPCODE_ILLEGAL:
	    {
	      FPRINTF (F, ".word");
	      FPRINTF (F, AFTER_INSTRUCTION);
	      FPRINTF (F, "%o", opcode);
	      goto done;
	    }
	  default:
	    /* TODO: is this a proper way of signalling an error? */
	    FPRINTF (F, "<internal error: unrecognized instruction type>");
	    return -1;
	  }
#undef OP
    }
 done:

  return memaddr - start_memaddr;
}
Commit	Line	Data
e135f41b NC	1	/* Print DEC PDP-11 instructions.
	2	Copyright 2001 Free Software Foundation, Inc.
	3
	4	This file is free software; you can redistribute it and/or modify
	5	it under the terms of the GNU General Public License as published by
	6	the Free Software Foundation; either version 2 of the License, or
	7	(at your option) any later version.
	8
	9	This program is distributed in the hope that it will be useful,
	10	but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	GNU General Public License for more details.
	13
	14	You should have received a copy of the GNU General Public License
	15	along with this program; if not, write to the Free Software
	16	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
	17
fc05c67f	18	#include "sysdep.h"
e135f41b NC	19	#include "dis-asm.h"
	20	#include "opcode/pdp11.h"
	21
	22	#define AFTER_INSTRUCTION "\t"
	23	#define OPERAND_SEPARATOR ", "
	24
	25	#define JUMP 0x1000 /* flag that this operand is used in a jump */
	26
	27	#define FPRINTF (*info->fprintf_func)
	28	#define F info->stream
	29
	30	/* sign-extend a 16-bit number in an int */
	31	#define SIGN_BITS (8 * sizeof (int) - 16)
	32	#define sign_extend(x) (((x) << SIGN_BITS) >> SIGN_BITS)
	33
	34	static int read_word PARAMS ((bfd_vma memaddr, int *word,
	35	disassemble_info *info));
	36	static void print_signed_octal PARAMS ((int n, disassemble_info *info));
	37	static void print_reg PARAMS ((int reg, disassemble_info *info));
	38	static void print_freg PARAMS ((int freg, disassemble_info *info));
	39	static int print_operand PARAMS ((bfd_vma *memaddr, int code,
	40	disassemble_info *info));
	41	int print_insn_pdp11 PARAMS ((bfd_vma memaddr, disassemble_info *info));
	42
	43	static int
	44	read_word (memaddr, word, info)
	45	bfd_vma memaddr;
	46	int *word;
	47	disassemble_info *info;
	48	{
	49	int status;
	50	bfd_byte x[2];
	51
	52	status = (*info->read_memory_func) (memaddr, x, 2, info);
	53	if (status != 0)
	54	return -1;
	55
	56	*word = x[1] << 8 \| x[0];
	57	return 0;
	58	}
	59
	60	static void
	61	print_signed_octal (n, info)
	62	int n;
	63	disassemble_info *info;
	64	{
	65	if (n < 0)
	66	FPRINTF (F, "-%o", -n);
	67	else
	68	FPRINTF (F, "%o", n);
	69	}
	70
	71	static void
	72	print_reg (reg, info)
	73	int reg;
	74	disassemble_info *info;
	75	{
	76	/* mask off the addressing mode, if any */
	77	reg &= 7;
	78
	79	switch (reg)
	80	{
	81	case 0: case 1: case 2: case 3: case 4: case 5:
	82	FPRINTF (F, "r%d", reg); break;
83	case 6: FPRINTF (F, "sp"); break;
84	case 7: FPRINTF (F, "pc"); break;
85	default: /* error */
86	}
87	}
88
89	static void
90	print_freg (freg, info)
91	int freg;
92	disassemble_info *info;
93	{
94	FPRINTF (F, "fr%d", freg);
95	}
96
97	static int
98	print_operand (memaddr, code, info)
99	bfd_vma *memaddr;
100	int code;
101	disassemble_info *info;
102	{
103	int mode = (code >> 3) & 7;
104	int reg = code & 7;
105	int disp;
106
107	switch (mode)
108	{
109	case 0:
110	print_reg (reg, info);
111	break;
112	case 1:
113	FPRINTF (F, "(");
114	print_reg (reg, info);
115	FPRINTF (F, ")");
116	break;
117	case 2:
118	if (reg == 7)
119	{
120	int data;
121	if (read_word (*memaddr, &data, info) < 0)
122	return -1;
123	FPRINTF (F, "$");
124	print_signed_octal (sign_extend (data), info);
125	*memaddr += 2;
126	}
127	else
128	{
129	FPRINTF (F, "(");
130	print_reg (reg, info);
131	FPRINTF (F, ")+");
132	}
133	break;
134	case 3:
135	if (reg == 7)
136	{
137	int address;
138	if (read_word (*memaddr, &address, info) < 0)
139	return -1;
140	FPRINTF (F, "*$%o", address);
141	*memaddr += 2;
142	}
143	else
144	{
145	FPRINTF (F, "*(");
146	print_reg (reg, info);
147	FPRINTF (F, ")+");
148	}
149	break;
150	case 4:
151	FPRINTF (F, "-(");
152	print_reg (reg, info);
153	FPRINTF (F, ")");
154	break;
155	case 5:
156	FPRINTF (F, "*-(");
157	print_reg (reg, info);
158	FPRINTF (F, ")");
159	break;
160	case 6:
161	case 7:
162	if (read_word (*memaddr, &disp, info) < 0)
163	return -1;
164	*memaddr += 2;
165	if (reg == 7)
166	{
167	bfd_vma address = *memaddr + sign_extend (disp);
168	if (!(code & JUMP))
169	FPRINTF (F, "*$");
170	(*info->print_address_func) (address, info);
171	}
172	else
173	{
174	if (mode == 7)
175	FPRINTF (F, "*");
176	print_signed_octal (sign_extend (disp), info);
177	FPRINTF (F, "(");
178	print_reg (reg, info);
179	FPRINTF (F, ")");
180	}
181	break;
182	}
183
184	return 0;
185	}
186
187	/* Print the PDP-11 instruction at address MEMADDR in debugged memory,
188	on INFO->STREAM. Returns length of the instruction, in bytes. */
189
190	int
191	print_insn_pdp11 (memaddr, info)
192	bfd_vma memaddr;
193	disassemble_info *info;
194	{
195	bfd_vma start_memaddr = memaddr;
196	int opcode;
197	int src, dst;
198	int i;
199
200	info->bytes_per_line = 6;
201	info->bytes_per_chunk = 2;
202	info->display_endian = BFD_ENDIAN_LITTLE;
203
204	if (read_word (memaddr, &opcode, info) != 0)
205	return -1;
206	memaddr += 2;
207
208	src = (opcode >> 6) & 0x3f;
209	dst = opcode & 0x3f;
210
211	for (i = 0; i < pdp11_num_opcodes; i++)
212	{
213	#define OP pdp11_opcodes[i]
214	if ((opcode & OP.mask) == OP.opcode)
215	switch (OP.type)
216	{
217	case PDP11_OPCODE_NO_OPS:
218	FPRINTF (F, OP.name);
c6843df5	219	goto done;
e135f41b NC	220	case PDP11_OPCODE_REG:
	221	FPRINTF (F, OP.name);
	222	FPRINTF (F, AFTER_INSTRUCTION);
	223	print_reg (dst, info);
c6843df5	224	goto done;
e135f41b NC	225	case PDP11_OPCODE_OP:
	226	FPRINTF (F, OP.name);
	227	FPRINTF (F, AFTER_INSTRUCTION);
	228	if (strcmp (OP.name, "jmp") == 0)
	229	dst \|= JUMP;
	230	if (print_operand (&memaddr, dst, info) < 0)
	231	return -1;
c6843df5	232	goto done;
e135f41b NC	233	case PDP11_OPCODE_REG_OP:
	234	FPRINTF (F, OP.name);
	235	FPRINTF (F, AFTER_INSTRUCTION);
	236	print_reg (src, info);
	237	FPRINTF (F, OPERAND_SEPARATOR);
	238	if (strcmp (OP.name, "jsr") == 0)
	239	dst \|= JUMP;
	240	if (print_operand (&memaddr, dst, info) < 0)
	241	return -1;
c6843df5	242	goto done;
e135f41b NC	243	case PDP11_OPCODE_REG_OP_REV:
	244	FPRINTF (F, OP.name);
	245	FPRINTF (F, AFTER_INSTRUCTION);
	246	if (print_operand (&memaddr, dst, info) < 0)
	247	return -1;
	248	FPRINTF (F, OPERAND_SEPARATOR);
	249	print_reg (src, info);
c6843df5	250	goto done;
e135f41b NC	251	case PDP11_OPCODE_AC_OP:
	252	{
	253	int ac = (opcode & 0xe0) >> 6;
	254	FPRINTF (F, OP.name);
	255	FPRINTF (F, AFTER_INSTRUCTION);
	256	print_freg (ac, info);
	257	FPRINTF (F, OPERAND_SEPARATOR);
	258	if (print_operand (&memaddr, dst, info) < 0)
	259	return -1;
c6843df5	260	goto done;
e135f41b NC	261	}
	262	case PDP11_OPCODE_OP_OP:
	263	FPRINTF (F, OP.name);
	264	FPRINTF (F, AFTER_INSTRUCTION);
	265	if (print_operand (&memaddr, src, info) < 0)
	266	return -1;
	267	FPRINTF (F, OPERAND_SEPARATOR);
	268	if (print_operand (&memaddr, dst, info) < 0)
	269	return -1;
c6843df5	270	goto done;
e135f41b NC	271	case PDP11_OPCODE_DISPL:
	272	{
	273	int displ = (opcode & 0xff) << 8;
	274	bfd_vma address = memaddr + (sign_extend (displ) >> 7);
	275	FPRINTF (F, OP.name);
	276	FPRINTF (F, AFTER_INSTRUCTION);
	277	(*info->print_address_func) (address, info);
c6843df5	278	goto done;
e135f41b NC	279	}
	280	case PDP11_OPCODE_REG_DISPL:
	281	{
	282	int displ = (opcode & 0x3f) << 10;
	283	bfd_vma address = memaddr + (sign_extend (displ) >> 9);
	284	FPRINTF (F, OP.name);
	285	FPRINTF (F, AFTER_INSTRUCTION);
	286	print_reg (src, info);
	287	FPRINTF (F, OPERAND_SEPARATOR);
	288	(*info->print_address_func) (address, info);
c6843df5	289	goto done;
e135f41b NC	290	}
	291	case PDP11_OPCODE_IMM8:
	292	{
	293	int code = opcode & 0xff;
	294	FPRINTF (F, OP.name);
	295	FPRINTF (F, AFTER_INSTRUCTION);
	296	FPRINTF (F, "%o", code);
c6843df5	297	goto done;
e135f41b NC	298	}
	299	case PDP11_OPCODE_IMM6:
	300	{
	301	int code = opcode & 0x3f;
	302	FPRINTF (F, OP.name);
	303	FPRINTF (F, AFTER_INSTRUCTION);
	304	FPRINTF (F, "%o", code);
c6843df5	305	goto done;
e135f41b NC	306	}
	307	case PDP11_OPCODE_IMM3:
	308	{
	309	int code = opcode & 7;
	310	FPRINTF (F, OP.name);
	311	FPRINTF (F, AFTER_INSTRUCTION);
	312	FPRINTF (F, "%o", code);
c6843df5 AM	313	goto done;
	314	}
	315	case PDP11_OPCODE_ILLEGAL:
	316	{
	317	FPRINTF (F, ".word");
	318	FPRINTF (F, AFTER_INSTRUCTION);
	319	FPRINTF (F, "%o", opcode);
	320	goto done;
e135f41b NC	321	}
	322	default:
	323	/* TODO: is this a proper way of signalling an error? */
	324	FPRINTF (F, "<internal error: unrecognized instruction type>");
	325	return -1;
	326	}
	327	#undef OP
	328	}
c6843df5	329	done:
e135f41b NC	330
	331	return memaddr - start_memaddr;
	332	}