[deliverable/binutils-gdb.git] / opcodes / s390-dis.c

/* s390-dis.c -- Disassemble S390 instructions
   Copyright 2000, 2001, 2002, 2003, 2005, 2007, 2008
   Free Software Foundation, Inc.
   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).

   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 <stdio.h>
#include "ansidecl.h"
#include "sysdep.h"
#include "dis-asm.h"
#include "opintl.h"
#include "opcode/s390.h"

static int init_flag = 0;
static int opc_index[256];
static int current_arch_mask = 0;

/* Set up index table for first opcode byte.  */

static void
init_disasm (struct disassemble_info *info)
{
  const struct s390_opcode *opcode;
  const struct s390_opcode *opcode_end;
  const char *p;

  memset (opc_index, 0, sizeof (opc_index));
  opcode_end = s390_opcodes + s390_num_opcodes;
  for (opcode = s390_opcodes; opcode < opcode_end; opcode++)
    {
      opc_index[(int) opcode->opcode[0]] = opcode - s390_opcodes;
      while ((opcode < opcode_end) &&
	     (opcode[1].opcode[0] == opcode->opcode[0]))
	opcode++;
    }

  for (p = info->disassembler_options; p != NULL; )
    {
      if (CONST_STRNEQ (p, "esa"))
	current_arch_mask = 1 << S390_OPCODE_ESA;
      else if (CONST_STRNEQ (p, "zarch"))
	current_arch_mask = 1 << S390_OPCODE_ZARCH;
      else
	fprintf (stderr, "Unknown S/390 disassembler option: %s\n", p);

      p = strchr (p, ',');
      if (p != NULL)
	p++;
    }

  if (!current_arch_mask)
    switch (info->mach)
      {
      case bfd_mach_s390_31:
	current_arch_mask = 1 << S390_OPCODE_ESA;
	break;
      case bfd_mach_s390_64:
	current_arch_mask = 1 << S390_OPCODE_ZARCH;
	break;
      default:
	abort ();
      }

  init_flag = 1;
}

/* Extracts an operand value from an instruction.  */
/* We do not perform the shift operation for larl-type address
   operands here since that would lead to an overflow of the 32 bit
   integer value.  Instead the shift operation is done when printing
   the operand in print_insn_s390.  */

static inline unsigned int
s390_extract_operand (unsigned char *insn, const struct s390_operand *operand)
{
  unsigned int val;
  int bits;

  /* Extract fragments of the operand byte for byte.  */
  insn += operand->shift / 8;
  bits = (operand->shift & 7) + operand->bits;
  val = 0;
  do
    {
      val <<= 8;
      val |= (unsigned int) *insn++;
      bits -= 8;
    }
  while (bits > 0);
  val >>= -bits;
  val &= ((1U << (operand->bits - 1)) << 1) - 1;

  /* Check for special long displacement case.  */
  if (operand->bits == 20 && operand->shift == 20)
    val = (val & 0xff) << 12 | (val & 0xfff00) >> 8;

  /* Sign extend value if the operand is signed or pc relative.  */
  if ((operand->flags & (S390_OPERAND_SIGNED | S390_OPERAND_PCREL))
      && (val & (1U << (operand->bits - 1))))
    val |= (-1U << (operand->bits - 1)) << 1;

  /* Length x in an instructions has real length x + 1.  */
  if (operand->flags & S390_OPERAND_LENGTH)
    val++;
  return val;
}

/* Print a S390 instruction.  */

int
print_insn_s390 (bfd_vma memaddr, struct disassemble_info *info)
{
  bfd_byte buffer[6];
  const struct s390_opcode *opcode;
  const struct s390_opcode *opcode_end;
  unsigned int value;
  int status, opsize, bufsize;
  char separator;

  if (init_flag == 0)
    init_disasm (info);

  /* The output looks better if we put 6 bytes on a line.  */
  info->bytes_per_line = 6;

  /* Every S390 instruction is max 6 bytes long.  */
  memset (buffer, 0, 6);
  status = (*info->read_memory_func) (memaddr, buffer, 6, info);
  if (status != 0)
    {
      for (bufsize = 0; bufsize < 6; bufsize++)
	if ((*info->read_memory_func) (memaddr, buffer, bufsize + 1, info) != 0)
	  break;
      if (bufsize <= 0)
	{
	  (*info->memory_error_func) (status, memaddr, info);
	  return -1;
	}
      /* Opsize calculation looks strange but it works
	 00xxxxxx -> 2 bytes, 01xxxxxx/10xxxxxx -> 4 bytes,
	 11xxxxxx -> 6 bytes.  */
      opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
      status = opsize > bufsize;
    }
  else
    {
      bufsize = 6;
      opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
    }

  if (status == 0)
    {
      const struct s390_opcode *op;

      /* Find the first match in the opcode table.  */
      opcode_end = s390_opcodes + s390_num_opcodes;
      for (opcode = s390_opcodes + opc_index[(int) buffer[0]];
	   (opcode < opcode_end) && (buffer[0] == opcode->opcode[0]);
	   opcode++)
	{
	  const struct s390_operand *operand;
	  const unsigned char *opindex;

	  /* Check architecture.  */
	  if (!(opcode->modes & current_arch_mask))
	    continue;

	  /* Check signature of the opcode.  */
	  if ((buffer[1] & opcode->mask[1]) != opcode->opcode[1]
	      || (buffer[2] & opcode->mask[2]) != opcode->opcode[2]
	      || (buffer[3] & opcode->mask[3]) != opcode->opcode[3]
	      || (buffer[4] & opcode->mask[4]) != opcode->opcode[4]
	      || (buffer[5] & opcode->mask[5]) != opcode->opcode[5])
	    continue;

	  /* Advance to an opcode with a more specific mask.  */
	  for (op = opcode + 1; op < opcode_end; op++)
	    {
	      if ((buffer[0] & op->mask[0]) != op->opcode[0])
		break;

	      if ((buffer[1] & op->mask[1]) != op->opcode[1]
		  || (buffer[2] & op->mask[2]) != op->opcode[2]
		  || (buffer[3] & op->mask[3]) != op->opcode[3]
		  || (buffer[4] & op->mask[4]) != op->opcode[4]
		  || (buffer[5] & op->mask[5]) != op->opcode[5])
		continue;

	      if (((int)opcode->mask[0] + opcode->mask[1] +
		   opcode->mask[2] + opcode->mask[3] +
		   opcode->mask[4] + opcode->mask[5]) <
		  ((int)op->mask[0] + op->mask[1] +
		   op->mask[2] + op->mask[3] +
		   op->mask[4] + op->mask[5]))
		opcode = op;
	    }

	  /* The instruction is valid.  */
	  if (opcode->operands[0] != 0)
	    (*info->fprintf_func) (info->stream, "%s\t", opcode->name);
	  else
	    (*info->fprintf_func) (info->stream, "%s", opcode->name);

	  /* Extract the operands.  */
	  separator = 0;
	  for (opindex = opcode->operands; *opindex != 0; opindex++)
	    {
	      operand = s390_operands + *opindex;
	      value = s390_extract_operand (buffer, operand);

	      if ((operand->flags & S390_OPERAND_INDEX) && value == 0)
		continue;
	      if ((operand->flags & S390_OPERAND_BASE) &&
		  value == 0 && separator == '(')
		{
		  separator = ',';
		  continue;
		}

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

	      if (operand->flags & S390_OPERAND_GPR)
		(*info->fprintf_func) (info->stream, "%%r%i", value);
	      else if (operand->flags & S390_OPERAND_FPR)
		(*info->fprintf_func) (info->stream, "%%f%i", value);
	      else if (operand->flags & S390_OPERAND_AR)
		(*info->fprintf_func) (info->stream, "%%a%i", value);
	      else if (operand->flags & S390_OPERAND_CR)
		(*info->fprintf_func) (info->stream, "%%c%i", value);
	      else if (operand->flags & S390_OPERAND_PCREL)
		(*info->print_address_func) (memaddr + (int)value + (int)value,
					     info);
	      else if (operand->flags & S390_OPERAND_SIGNED)
		(*info->fprintf_func) (info->stream, "%i", (int) value);
	      else
		(*info->fprintf_func) (info->stream, "%u", value);

	      if (operand->flags & S390_OPERAND_DISP)
		{
		  separator = '(';
		}
	      else if (operand->flags & S390_OPERAND_BASE)
		{
		  (*info->fprintf_func) (info->stream, ")");
		  separator = ',';
		}
	      else
		separator = ',';
	    }

	  /* Found instruction, printed it, return its size.  */
	  return opsize;
	}
      /* No matching instruction found, fall through to hex print.  */
    }

  if (bufsize >= 4)
    {
      value = (unsigned int) buffer[0];
      value = (value << 8) + (unsigned int) buffer[1];
      value = (value << 8) + (unsigned int) buffer[2];
      value = (value << 8) + (unsigned int) buffer[3];
      (*info->fprintf_func) (info->stream, ".long\t0x%08x", value);
      return 4;
    }
  else if (bufsize >= 2)
    {
      value = (unsigned int) buffer[0];
      value = (value << 8) + (unsigned int) buffer[1];
      (*info->fprintf_func) (info->stream, ".short\t0x%04x", value);
      return 2;
    }
  else
    {
      value = (unsigned int) buffer[0];
      (*info->fprintf_func) (info->stream, ".byte\t0x%02x", value);
      return 1;
    }
}

void
print_s390_disassembler_options (FILE *stream)
{
  fprintf (stream, _("\n\
The following S/390 specific disassembler options are supported for use\n\
with the -M switch (multiple options should be separated by commas):\n"));

  fprintf (stream, _("  esa         Disassemble in ESA architecture mode\n"));
  fprintf (stream, _("  zarch       Disassemble in z/Architecture mode\n"));
}
Commit	Line	Data
a85d7ed0	1	/* s390-dis.c -- Disassemble S390 instructions
aa820537 AM	2	Copyright 2000, 2001, 2002, 2003, 2005, 2007, 2008
aa820537 AM	3	Free Software Foundation, Inc.
a85d7ed0 NC	4	Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
a85d7ed0 NC	5
9b201bb5	6	This file is part of the GNU opcodes library.
a85d7ed0	7
9b201bb5	8	This library is free software; you can redistribute it and/or modify
a85d7ed0	9	it under the terms of the GNU General Public License as published by
9b201bb5 NC	10	the Free Software Foundation; either version 3, or (at your option)
9b201bb5 NC	11	any later version.
a85d7ed0	12
9b201bb5 NC	13	It is distributed in the hope that it will be useful, but WITHOUT
	14	ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
	15	or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
	16	License for more details.
a85d7ed0 NC	17
a85d7ed0 NC	18	You should have received a copy of the GNU General Public License
9b201bb5 NC	19	along with this file; see the file COPYING. If not, write to the
	20	Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
	21	MA 02110-1301, USA. */
a85d7ed0 NC	22
	23	#include <stdio.h>
	24	#include "ansidecl.h"
	25	#include "sysdep.h"
	26	#include "dis-asm.h"
112b7c50	27	#include "opintl.h"
a85d7ed0 NC	28	#include "opcode/s390.h"
	29
	30	static int init_flag = 0;
	31	static int opc_index[256];
	32	static int current_arch_mask = 0;
	33
44f2a95d KH	34	/* Set up index table for first opcode byte. */
	35
	36	static void
47b0e7ad	37	init_disasm (struct disassemble_info *info)
a85d7ed0 NC	38	{
	39	const struct s390_opcode *opcode;
	40	const struct s390_opcode *opcode_end;
112b7c50	41	const char *p;
a85d7ed0	42
44f2a95d	43	memset (opc_index, 0, sizeof (opc_index));
a85d7ed0	44	opcode_end = s390_opcodes + s390_num_opcodes;
44f2a95d KH	45	for (opcode = s390_opcodes; opcode < opcode_end; opcode++)
	46	{
	47	opc_index[(int) opcode->opcode[0]] = opcode - s390_opcodes;
	48	while ((opcode < opcode_end) &&
	49	(opcode[1].opcode[0] == opcode->opcode[0]))
	50	opcode++;
	51	}
112b7c50 AK	52
112b7c50 AK	53	for (p = info->disassembler_options; p != NULL; )
44f2a95d	54	{
112b7c50 AK	55	if (CONST_STRNEQ (p, "esa"))
	56	current_arch_mask = 1 << S390_OPCODE_ESA;
	57	else if (CONST_STRNEQ (p, "zarch"))
	58	current_arch_mask = 1 << S390_OPCODE_ZARCH;
	59	else
	60	fprintf (stderr, "Unknown S/390 disassembler option: %s\n", p);
	61
	62	p = strchr (p, ',');
	63	if (p != NULL)
	64	p++;
44f2a95d	65	}
112b7c50 AK	66
	67	if (!current_arch_mask)
	68	switch (info->mach)
	69	{
	70	case bfd_mach_s390_31:
	71	current_arch_mask = 1 << S390_OPCODE_ESA;
	72	break;
	73	case bfd_mach_s390_64:
	74	current_arch_mask = 1 << S390_OPCODE_ZARCH;
	75	break;
	76	default:
	77	abort ();
	78	}
	79
a85d7ed0 NC	80	init_flag = 1;
	81	}
	82
	83	/* Extracts an operand value from an instruction. */
7330f9c3 AK	84	/* We do not perform the shift operation for larl-type address
	85	operands here since that would lead to an overflow of the 32 bit
	86	integer value. Instead the shift operation is done when printing
	87	the operand in print_insn_s390. */
a85d7ed0 NC	88
a85d7ed0 NC	89	static inline unsigned int
47b0e7ad	90	s390_extract_operand (unsigned char insn, const struct s390_operand operand)
a85d7ed0 NC	91	{
	92	unsigned int val;
	93	int bits;
	94
44f2a95d KH	95	/* Extract fragments of the operand byte for byte. */
44f2a95d KH	96	insn += operand->shift / 8;
a85d7ed0 NC	97	bits = (operand->shift & 7) + operand->bits;
a85d7ed0 NC	98	val = 0;
44f2a95d KH	99	do
	100	{
	101	val <<= 8;
	102	val \|= (unsigned int) *insn++;
	103	bits -= 8;
	104	}
	105	while (bits > 0);
a85d7ed0	106	val >>= -bits;
44f2a95d KH	107	val &= ((1U << (operand->bits - 1)) << 1) - 1;
44f2a95d KH	108
bac02689 MS	109	/* Check for special long displacement case. */
	110	if (operand->bits == 20 && operand->shift == 20)
	111	val = (val & 0xff) << 12 \| (val & 0xfff00) >> 8;
	112
44f2a95d KH	113	/* Sign extend value if the operand is signed or pc relative. */
	114	if ((operand->flags & (S390_OPERAND_SIGNED \| S390_OPERAND_PCREL))
	115	&& (val & (1U << (operand->bits - 1))))
	116	val \|= (-1U << (operand->bits - 1)) << 1;
	117
47b0e7ad	118	/* Length x in an instructions has real length x + 1. */
a85d7ed0 NC	119	if (operand->flags & S390_OPERAND_LENGTH)
	120	val++;
	121	return val;
	122	}
	123
	124	/* Print a S390 instruction. */
	125
	126	int
47b0e7ad	127	print_insn_s390 (bfd_vma memaddr, struct disassemble_info *info)
a85d7ed0 NC	128	{
	129	bfd_byte buffer[6];
	130	const struct s390_opcode *opcode;
	131	const struct s390_opcode *opcode_end;
	132	unsigned int value;
	133	int status, opsize, bufsize;
	134	char separator;
	135
	136	if (init_flag == 0)
44f2a95d	137	init_disasm (info);
a85d7ed0 NC	138
	139	/* The output looks better if we put 6 bytes on a line. */
	140	info->bytes_per_line = 6;
	141
	142	/* Every S390 instruction is max 6 bytes long. */
44f2a95d	143	memset (buffer, 0, 6);
a85d7ed0	144	status = (*info->read_memory_func) (memaddr, buffer, 6, info);
44f2a95d KH	145	if (status != 0)
	146	{
	147	for (bufsize = 0; bufsize < 6; bufsize++)
	148	if ((*info->read_memory_func) (memaddr, buffer, bufsize + 1, info) != 0)
	149	break;
	150	if (bufsize <= 0)
	151	{
	152	(*info->memory_error_func) (status, memaddr, info);
	153	return -1;
	154	}
	155	/* Opsize calculation looks strange but it works
	156	00xxxxxx -> 2 bytes, 01xxxxxx/10xxxxxx -> 4 bytes,
	157	11xxxxxx -> 6 bytes. */
	158	opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
	159	status = opsize > bufsize;
	160	}
	161	else
	162	{
	163	bufsize = 6;
	164	opsize = ((((buffer[0] >> 6) + 1) >> 1) + 1) << 1;
	165	}
	166
	167	if (status == 0)
	168	{
02cbf767 AK	169	const struct s390_opcode *op;
02cbf767 AK	170
44f2a95d KH	171	/* Find the first match in the opcode table. */
	172	opcode_end = s390_opcodes + s390_num_opcodes;
	173	for (opcode = s390_opcodes + opc_index[(int) buffer[0]];
	174	(opcode < opcode_end) && (buffer[0] == opcode->opcode[0]);
	175	opcode++)
	176	{
	177	const struct s390_operand *operand;
	178	const unsigned char *opindex;
	179
	180	/* Check architecture. */
af169f23	181	if (!(opcode->modes & current_arch_mask))
44f2a95d	182	continue;
02cbf767	183
44f2a95d KH	184	/* Check signature of the opcode. */
	185	if ((buffer[1] & opcode->mask[1]) != opcode->opcode[1]
	186	\|\| (buffer[2] & opcode->mask[2]) != opcode->opcode[2]
	187	\|\| (buffer[3] & opcode->mask[3]) != opcode->opcode[3]
	188	\|\| (buffer[4] & opcode->mask[4]) != opcode->opcode[4]
	189	\|\| (buffer[5] & opcode->mask[5]) != opcode->opcode[5])
	190	continue;
	191
02cbf767 AK	192	/* Advance to an opcode with a more specific mask. */
	193	for (op = opcode + 1; op < opcode_end; op++)
	194	{
	195	if ((buffer[0] & op->mask[0]) != op->opcode[0])
	196	break;
	197
	198	if ((buffer[1] & op->mask[1]) != op->opcode[1]
	199	\|\| (buffer[2] & op->mask[2]) != op->opcode[2]
	200	\|\| (buffer[3] & op->mask[3]) != op->opcode[3]
	201	\|\| (buffer[4] & op->mask[4]) != op->opcode[4]
	202	\|\| (buffer[5] & op->mask[5]) != op->opcode[5])
	203	continue;
	204
	205	if (((int)opcode->mask[0] + opcode->mask[1] +
	206	opcode->mask[2] + opcode->mask[3] +
	207	opcode->mask[4] + opcode->mask[5]) <
	208	((int)op->mask[0] + op->mask[1] +
	209	op->mask[2] + op->mask[3] +
	210	op->mask[4] + op->mask[5]))
	211	opcode = op;
	212	}
	213
44f2a95d KH	214	/* The instruction is valid. */
	215	if (opcode->operands[0] != 0)
	216	(*info->fprintf_func) (info->stream, "%s\t", opcode->name);
	217	else
	218	(*info->fprintf_func) (info->stream, "%s", opcode->name);
	219
	220	/* Extract the operands. */
	221	separator = 0;
	222	for (opindex = opcode->operands; *opindex != 0; opindex++)
	223	{
44f2a95d KH	224	operand = s390_operands + *opindex;
	225	value = s390_extract_operand (buffer, operand);
	226
	227	if ((operand->flags & S390_OPERAND_INDEX) && value == 0)
	228	continue;
	229	if ((operand->flags & S390_OPERAND_BASE) &&
	230	value == 0 && separator == '(')
	231	{
	232	separator = ',';
	233	continue;
	234	}
	235
	236	if (separator)
	237	(*info->fprintf_func) (info->stream, "%c", separator);
	238
	239	if (operand->flags & S390_OPERAND_GPR)
	240	(*info->fprintf_func) (info->stream, "%%r%i", value);
	241	else if (operand->flags & S390_OPERAND_FPR)
	242	(*info->fprintf_func) (info->stream, "%%f%i", value);
	243	else if (operand->flags & S390_OPERAND_AR)
	244	(*info->fprintf_func) (info->stream, "%%a%i", value);
	245	else if (operand->flags & S390_OPERAND_CR)
	246	(*info->fprintf_func) (info->stream, "%%c%i", value);
	247	else if (operand->flags & S390_OPERAND_PCREL)
c8676ae4 AK	248	(*info->print_address_func) (memaddr + (int)value + (int)value,
c8676ae4 AK	249	info);
44f2a95d KH	250	else if (operand->flags & S390_OPERAND_SIGNED)
	251	(*info->fprintf_func) (info->stream, "%i", (int) value);
	252	else
ad101263	253	(*info->fprintf_func) (info->stream, "%u", value);
44f2a95d KH	254
	255	if (operand->flags & S390_OPERAND_DISP)
	256	{
	257	separator = '(';
	258	}
	259	else if (operand->flags & S390_OPERAND_BASE)
	260	{
	261	(*info->fprintf_func) (info->stream, ")");
	262	separator = ',';
	263	}
	264	else
	265	separator = ',';
	266	}
	267
	268	/* Found instruction, printed it, return its size. */
	269	return opsize;
	270	}
	271	/* No matching instruction found, fall through to hex print. */
	272	}
	273
	274	if (bufsize >= 4)
	275	{
	276	value = (unsigned int) buffer[0];
	277	value = (value << 8) + (unsigned int) buffer[1];
	278	value = (value << 8) + (unsigned int) buffer[2];
	279	value = (value << 8) + (unsigned int) buffer[3];
	280	(*info->fprintf_func) (info->stream, ".long\t0x%08x", value);
	281	return 4;
	282	}
	283	else if (bufsize >= 2)
	284	{
	285	value = (unsigned int) buffer[0];
	286	value = (value << 8) + (unsigned int) buffer[1];
	287	(*info->fprintf_func) (info->stream, ".short\t0x%04x", value);
	288	return 2;
a85d7ed0	289	}
44f2a95d KH	290	else
	291	{
	292	value = (unsigned int) buffer[0];
	293	(*info->fprintf_func) (info->stream, ".byte\t0x%02x", value);
	294	return 1;
a85d7ed0	295	}
a85d7ed0	296	}
112b7c50 AK	297
	298	void
	299	print_s390_disassembler_options (FILE *stream)
	300	{
	301	fprintf (stream, _("\n\
	302	The following S/390 specific disassembler options are supported for use\n\
	303	with the -M switch (multiple options should be separated by commas):\n"));
	304
	305	fprintf (stream, _(" esa Disassemble in ESA architecture mode\n"));
	306	fprintf (stream, _(" zarch Disassemble in z/Architecture mode\n"));
	307	}