xref: /src/external/gpl3/gdb.old/dist/opcodes/ppc-dis.c

/* ppc-dis.c -- Disassemble PowerPC instructions
   Copyright (C) 1994-2016 Free Software Foundation, Inc.
   Written by Ian Lance Taylor, Cygnus Support

   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 "sysdep.h"
#include <stdio.h>
#include "dis-asm.h"
#include "elf-bfd.h"
#include "elf/ppc.h"
#include "opintl.h"
#include "opcode/ppc.h"

/* This file provides several disassembler functions, all of which use
   the disassembler interface defined in dis-asm.h.  Several functions
   are provided because this file handles disassembly for the PowerPC
   in both big and little endian mode and also for the POWER (RS/6000)
   chip.  */
static int print_insn_powerpc (bfd_vma, struct disassemble_info *, int,
			       ppc_cpu_t);

struct dis_private
{
  /* Stash the result of parsing disassembler_options here.  */
  ppc_cpu_t dialect;
} private;

#define POWERPC_DIALECT(INFO) \
  (((struct dis_private *) ((INFO)->private_data))->dialect)

struct ppc_mopt {
  const char *opt;
  ppc_cpu_t cpu;
  ppc_cpu_t sticky;
};

struct ppc_mopt ppc_opts[] = {
  { "403",     PPC_OPCODE_PPC | PPC_OPCODE_403,
    0 },
  { "405",     PPC_OPCODE_PPC | PPC_OPCODE_403 | PPC_OPCODE_405,
    0 },
  { "440",     (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_440
		| PPC_OPCODE_ISEL | PPC_OPCODE_RFMCI),
    0 },
  { "464",     (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_440
		| PPC_OPCODE_ISEL | PPC_OPCODE_RFMCI),
    0 },
  { "476",     (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_440
		| PPC_OPCODE_476 | PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5),
    0 },
  { "601",     PPC_OPCODE_PPC | PPC_OPCODE_601,
    0 },
  { "603",     PPC_OPCODE_PPC,
    0 },
  { "604",     PPC_OPCODE_PPC,
    0 },
  { "620",     PPC_OPCODE_PPC | PPC_OPCODE_64,
    0 },
  { "7400",    PPC_OPCODE_PPC | PPC_OPCODE_ALTIVEC,
    0 },
  { "7410",    PPC_OPCODE_PPC | PPC_OPCODE_ALTIVEC,
    0 },
  { "7450",    PPC_OPCODE_PPC | PPC_OPCODE_7450 | PPC_OPCODE_ALTIVEC,
    0 },
  { "7455",    PPC_OPCODE_PPC | PPC_OPCODE_ALTIVEC,
    0 },
  { "750cl",   PPC_OPCODE_PPC | PPC_OPCODE_750 | PPC_OPCODE_PPCPS
    , 0 },
  { "821",     PPC_OPCODE_PPC | PPC_OPCODE_860,
    0 },
  { "850",     PPC_OPCODE_PPC | PPC_OPCODE_860,
    0 },
  { "860",     PPC_OPCODE_PPC | PPC_OPCODE_860,
    0 },
  { "a2",      (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5 | PPC_OPCODE_CACHELCK | PPC_OPCODE_64
		| PPC_OPCODE_A2),
    0 },
  { "altivec", PPC_OPCODE_PPC,
    PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2 },
  { "any",     0,
    PPC_OPCODE_ANY },
  { "booke",   PPC_OPCODE_PPC | PPC_OPCODE_BOOKE,
    0 },
  { "booke32", PPC_OPCODE_PPC | PPC_OPCODE_BOOKE,
    0 },
  { "cell",    (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_CELL | PPC_OPCODE_ALTIVEC),
    0 },
  { "com",     PPC_OPCODE_COMMON,
    0 },
  { "e300",    PPC_OPCODE_PPC | PPC_OPCODE_E300,
    0 },
  { "e500",    (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_SPE
		| PPC_OPCODE_ISEL | PPC_OPCODE_EFS | PPC_OPCODE_BRLOCK
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500),
    0 },
  { "e500mc",  (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_ISEL
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500MC),
    0 },
  { "e500mc64",  (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_ISEL
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500MC | PPC_OPCODE_64 | PPC_OPCODE_POWER5
		| PPC_OPCODE_POWER6 | PPC_OPCODE_POWER7),
    0 },
  { "e5500",    (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_ISEL
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500MC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7),
    0 },
  { "e6500",   (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_ISEL
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500MC | PPC_OPCODE_64 | PPC_OPCODE_ALTIVEC
		| PPC_OPCODE_ALTIVEC2 | PPC_OPCODE_E6500 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_POWER7),
    0 },
  { "e500x2",  (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_SPE
		| PPC_OPCODE_ISEL | PPC_OPCODE_EFS | PPC_OPCODE_BRLOCK
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500),
    0 },
  { "efs",     PPC_OPCODE_PPC | PPC_OPCODE_EFS,
    0 },
  { "power4",  PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4,
    0 },
  { "power5",  (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5),
    0 },
  { "power6",  (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_ALTIVEC),
    0 },
  { "power7",  (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_ALTIVEC | PPC_OPCODE_VSX),
    0 },
  { "power8",  (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_POWER8 | PPC_OPCODE_HTM
		| PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2 | PPC_OPCODE_VSX),
    0 },
  { "power9",  (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_POWER8 | PPC_OPCODE_POWER9
		| PPC_OPCODE_HTM | PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2
		| PPC_OPCODE_VSX | PPC_OPCODE_VSX3 ),
    0 },
  { "ppc",     PPC_OPCODE_PPC,
    0 },
  { "ppc32",   PPC_OPCODE_PPC,
    0 },
  { "ppc64",   PPC_OPCODE_PPC | PPC_OPCODE_64,
    0 },
  { "ppc64bridge", PPC_OPCODE_PPC | PPC_OPCODE_64_BRIDGE,
    0 },
  { "ppcps",   PPC_OPCODE_PPC | PPC_OPCODE_PPCPS,
    0 },
  { "pwr",     PPC_OPCODE_POWER,
    0 },
  { "pwr2",    PPC_OPCODE_POWER | PPC_OPCODE_POWER2,
    0 },
  { "pwr4",    PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4,
    0 },
  { "pwr5",    (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5),
    0 },
  { "pwr5x",   (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5),
    0 },
  { "pwr6",    (PPC_OPCODE_PPC | PPC_OPCODE_64 | PPC_OPCODE_POWER4
		| PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6 | PPC_OPCODE_ALTIVEC),
    0 },
  { "pwr7",    (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_ALTIVEC | PPC_OPCODE_VSX),
    0 },
  { "pwr8",    (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_POWER8 | PPC_OPCODE_HTM
		| PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2 | PPC_OPCODE_VSX),
    0 },
  { "pwr9",    (PPC_OPCODE_PPC | PPC_OPCODE_ISEL | PPC_OPCODE_64
		| PPC_OPCODE_POWER4 | PPC_OPCODE_POWER5 | PPC_OPCODE_POWER6
		| PPC_OPCODE_POWER7 | PPC_OPCODE_POWER8 | PPC_OPCODE_POWER9
		| PPC_OPCODE_HTM | PPC_OPCODE_ALTIVEC | PPC_OPCODE_ALTIVEC2
		| PPC_OPCODE_VSX | PPC_OPCODE_VSX3 ),
    0 },
  { "pwrx",    PPC_OPCODE_POWER | PPC_OPCODE_POWER2,
    0 },
  { "spe",     PPC_OPCODE_PPC | PPC_OPCODE_EFS,
    PPC_OPCODE_SPE },
  { "titan",   (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE | PPC_OPCODE_PMR
		| PPC_OPCODE_RFMCI | PPC_OPCODE_TITAN),
    0 },
  { "vle",     (PPC_OPCODE_PPC | PPC_OPCODE_BOOKE| PPC_OPCODE_SPE
		| PPC_OPCODE_ISEL | PPC_OPCODE_EFS | PPC_OPCODE_BRLOCK
		| PPC_OPCODE_PMR | PPC_OPCODE_CACHELCK | PPC_OPCODE_RFMCI
		| PPC_OPCODE_E500),
    PPC_OPCODE_VLE },
  { "vsx",     PPC_OPCODE_PPC,
    PPC_OPCODE_VSX | PPC_OPCODE_VSX3 },
  { "htm",     PPC_OPCODE_PPC,
    PPC_OPCODE_HTM },
};

/* Switch between Booke and VLE dialects for interlinked dumps.  */
static ppc_cpu_t
get_powerpc_dialect (struct disassemble_info *info)
{
  ppc_cpu_t dialect = 0;

  dialect = POWERPC_DIALECT (info);

  /* Disassemble according to the section headers flags for VLE-mode.  */
  if (dialect & PPC_OPCODE_VLE
      && info->section->owner != NULL
      && bfd_get_flavour (info->section->owner) == bfd_target_elf_flavour
      && elf_object_id (info->section->owner) == PPC32_ELF_DATA
      && (elf_section_flags (info->section) & SHF_PPC_VLE) != 0)
    return dialect;
  else
    return dialect & ~ PPC_OPCODE_VLE;
}

/* Handle -m and -M options that set cpu type, and .machine arg.  */

ppc_cpu_t
ppc_parse_cpu (ppc_cpu_t ppc_cpu, ppc_cpu_t *sticky, const char *arg)
{
  unsigned int i;

  for (i = 0; i < sizeof (ppc_opts) / sizeof (ppc_opts[0]); i++)
    if (strcmp (ppc_opts[i].opt, arg) == 0)
      {
	if (ppc_opts[i].sticky)
	  {
	    *sticky |= ppc_opts[i].sticky;
	    if ((ppc_cpu & ~*sticky) != 0)
	      break;
	  }
	ppc_cpu = ppc_opts[i].cpu;
	break;
      }
  if (i >= sizeof (ppc_opts) / sizeof (ppc_opts[0]))
    return 0;

  ppc_cpu |= *sticky;
  return ppc_cpu;
}

/* Determine which set of machines to disassemble for.  */

static void
powerpc_init_dialect (struct disassemble_info *info)
{
  ppc_cpu_t dialect = 0;
  ppc_cpu_t sticky = 0;
  char *arg;
  struct dis_private *priv = calloc (sizeof (*priv), 1);

  if (priv == NULL)
    priv = &private;

  switch (info->mach)
    {
    case bfd_mach_ppc_403:
    case bfd_mach_ppc_403gc:
      dialect = ppc_parse_cpu (dialect, &sticky, "403");
      break;
    case bfd_mach_ppc_405:
      dialect = ppc_parse_cpu (dialect, &sticky, "405");
      break;
    case bfd_mach_ppc_601:
      dialect = ppc_parse_cpu (dialect, &sticky, "601");
      break;
    case bfd_mach_ppc_a35:
    case bfd_mach_ppc_rs64ii:
    case bfd_mach_ppc_rs64iii:
      dialect = ppc_parse_cpu (dialect, &sticky, "pwr2") | PPC_OPCODE_64;
      break;
    case bfd_mach_ppc_e500:
      dialect = ppc_parse_cpu (dialect, &sticky, "e500");
      break;
    case bfd_mach_ppc_e500mc:
      dialect = ppc_parse_cpu (dialect, &sticky, "e500mc");
      break;
    case bfd_mach_ppc_e500mc64:
      dialect = ppc_parse_cpu (dialect, &sticky, "e500mc64");
      break;
    case bfd_mach_ppc_e5500:
      dialect = ppc_parse_cpu (dialect, &sticky, "e5500");
      break;
    case bfd_mach_ppc_e6500:
      dialect = ppc_parse_cpu (dialect, &sticky, "e6500");
      break;
    case bfd_mach_ppc_titan:
      dialect = ppc_parse_cpu (dialect, &sticky, "titan");
      break;
    case bfd_mach_ppc_vle:
      dialect = ppc_parse_cpu (dialect, &sticky, "vle");
      break;
    default:
      dialect = ppc_parse_cpu (dialect, &sticky, "power9") | PPC_OPCODE_ANY;
    }

  arg = info->disassembler_options;
  while (arg != NULL)
    {
      ppc_cpu_t new_cpu = 0;
      char *end = strchr (arg, ',');

      if (end != NULL)
	*end = 0;

      if ((new_cpu = ppc_parse_cpu (dialect, &sticky, arg)) != 0)
	dialect = new_cpu;
      else if (strcmp (arg, "32") == 0)
	dialect &= ~(ppc_cpu_t) PPC_OPCODE_64;
      else if (strcmp (arg, "64") == 0)
	dialect |= PPC_OPCODE_64;
      else
	fprintf (stderr, _("warning: ignoring unknown -M%s option\n"), arg);

      if (end != NULL)
	*end++ = ',';
      arg = end;
    }

  info->private_data = priv;
  POWERPC_DIALECT(info) = dialect;
}

#define PPC_OPCD_SEGS 64
static unsigned short powerpc_opcd_indices[PPC_OPCD_SEGS+1];
#define VLE_OPCD_SEGS 32
static unsigned short vle_opcd_indices[VLE_OPCD_SEGS+1];

/* Calculate opcode table indices to speed up disassembly,
   and init dialect.  */

void
disassemble_init_powerpc (struct disassemble_info *info)
{
  int i;
  unsigned short last;

  if (powerpc_opcd_indices[PPC_OPCD_SEGS] == 0)
    {

      i = powerpc_num_opcodes;
      while (--i >= 0)
        {
          unsigned op = PPC_OP (powerpc_opcodes[i].opcode);

          powerpc_opcd_indices[op] = i;
        }

      last = powerpc_num_opcodes;
      for (i = PPC_OPCD_SEGS; i > 0; --i)
        {
          if (powerpc_opcd_indices[i] == 0)
	    powerpc_opcd_indices[i] = last;
          last = powerpc_opcd_indices[i];
        }

      i = vle_num_opcodes;
      while (--i >= 0)
        {
          unsigned op = VLE_OP (vle_opcodes[i].opcode, vle_opcodes[i].mask);
          unsigned seg = VLE_OP_TO_SEG (op);

          vle_opcd_indices[seg] = i;
        }

      last = vle_num_opcodes;
      for (i = VLE_OPCD_SEGS; i > 0; --i)
        {
          if (vle_opcd_indices[i] == 0)
	    vle_opcd_indices[i] = last;
          last = vle_opcd_indices[i];
        }
    }

  if (info->arch == bfd_arch_powerpc)
    powerpc_init_dialect (info);
}

/* Print a big endian PowerPC instruction.  */

int
print_insn_big_powerpc (bfd_vma memaddr, struct disassemble_info *info)
{
  return print_insn_powerpc (memaddr, info, 1, get_powerpc_dialect (info));
}

/* Print a little endian PowerPC instruction.  */

int
print_insn_little_powerpc (bfd_vma memaddr, struct disassemble_info *info)
{
  return print_insn_powerpc (memaddr, info, 0, get_powerpc_dialect (info));
}

/* Print a POWER (RS/6000) instruction.  */

int
print_insn_rs6000 (bfd_vma memaddr, struct disassemble_info *info)
{
  return print_insn_powerpc (memaddr, info, 1, PPC_OPCODE_POWER);
}

/* Extract the operand value from the PowerPC or POWER instruction.  */

static long
operand_value_powerpc (const struct powerpc_operand *operand,
		       unsigned long insn, ppc_cpu_t dialect)
{
  long value;
  int invalid;
  /* Extract the value from the instruction.  */
  if (operand->extract)
    value = (*operand->extract) (insn, dialect, &invalid);
  else
    {
      if (operand->shift >= 0)
	value = (insn >> operand->shift) & operand->bitm;
      else
	value = (insn << -operand->shift) & operand->bitm;
      if ((operand->flags & PPC_OPERAND_SIGNED) != 0)
	{
	  /* BITM is always some number of zeros followed by some
	     number of ones, followed by some number of zeros.  */
	  unsigned long top = operand->bitm;
	  /* top & -top gives the rightmost 1 bit, so this
	     fills in any trailing zeros.  */
	  top |= (top & -top) - 1;
	  top &= ~(top >> 1);
	  value = (value ^ top) - top;
	}
    }

  return value;
}

/* Determine whether the optional operand(s) should be printed.  */

static int
skip_optional_operands (const unsigned char *opindex,
			unsigned long insn, ppc_cpu_t dialect)
{
  const struct powerpc_operand *operand;

  for (; *opindex != 0; opindex++)
    {
      operand = &powerpc_operands[*opindex];
      if ((operand->flags & PPC_OPERAND_NEXT) != 0
	  || ((operand->flags & PPC_OPERAND_OPTIONAL) != 0
	      && operand_value_powerpc (operand, insn, dialect) !=
		 ppc_optional_operand_value (operand)))
	return 0;
    }

  return 1;
}

/* Find a match for INSN in the opcode table, given machine DIALECT.
   A DIALECT of -1 is special, matching all machine opcode variations.  */

static const struct powerpc_opcode *
lookup_powerpc (unsigned long insn, ppc_cpu_t dialect)
{
  const struct powerpc_opcode *opcode;
  const struct powerpc_opcode *opcode_end;
  unsigned long op;

  /* Get the major opcode of the instruction.  */
  op = PPC_OP (insn);

  /* Find the first match in the opcode table for this major opcode.  */
  opcode_end = powerpc_opcodes + powerpc_opcd_indices[op + 1];
  for (opcode = powerpc_opcodes + powerpc_opcd_indices[op];
       opcode < opcode_end;
       ++opcode)
    {
      const unsigned char *opindex;
      const struct powerpc_operand *operand;
      int invalid;

      if ((insn & opcode->mask) != opcode->opcode
	  || (dialect != (ppc_cpu_t) -1
	      && ((opcode->flags & dialect) == 0
		  || (opcode->deprecated & dialect) != 0)))
	continue;

      /* Check validity of operands.  */
      invalid = 0;
      for (opindex = opcode->operands; *opindex != 0; opindex++)
	{
	  operand = powerpc_operands + *opindex;
	  if (operand->extract)
	    (*operand->extract) (insn, dialect, &invalid);
	}
      if (invalid)
	continue;

      return opcode;
    }

  return NULL;
}

/* Find a match for INSN in the VLE opcode table.  */

static const struct powerpc_opcode *
lookup_vle (unsigned long insn)
{
  const struct powerpc_opcode *opcode;
  const struct powerpc_opcode *opcode_end;
  unsigned op, seg;

  op = PPC_OP (insn);
  if (op >= 0x20 && op <= 0x37)
    {
      /* This insn has a 4-bit opcode.  */
      op &= 0x3c;
    }
  seg = VLE_OP_TO_SEG (op);

  /* Find the first match in the opcode table for this major opcode.  */
  opcode_end = vle_opcodes + vle_opcd_indices[seg + 1];
  for (opcode = vle_opcodes + vle_opcd_indices[seg];
       opcode < opcode_end;
       ++opcode)
    {
      unsigned long table_opcd = opcode->opcode;
      unsigned long table_mask = opcode->mask;
      bfd_boolean table_op_is_short = PPC_OP_SE_VLE(table_mask);
      unsigned long insn2;
      const unsigned char *opindex;
      const struct powerpc_operand *operand;
      int invalid;

      insn2 = insn;
      if (table_op_is_short)
	insn2 >>= 16;
      if ((insn2 & table_mask) != table_opcd)
	continue;

      /* Check validity of operands.  */
      invalid = 0;
      for (opindex = opcode->operands; *opindex != 0; ++opindex)
	{
	  operand = powerpc_operands + *opindex;
	  if (operand->extract)
	    (*operand->extract) (insn, (ppc_cpu_t)0, &invalid);
	}
      if (invalid)
	continue;

      return opcode;
    }

  return NULL;
}

/* Print a PowerPC or POWER instruction.  */

static int
print_insn_powerpc (bfd_vma memaddr,
		    struct disassemble_info *info,
		    int bigendian,
		    ppc_cpu_t dialect)
{
  bfd_byte buffer[4];
  int status;
  unsigned long insn;
  const struct powerpc_opcode *opcode;
  bfd_boolean insn_is_short;

  status = (*info->read_memory_func) (memaddr, buffer, 4, info);
  if (status != 0)
    {
      /* The final instruction may be a 2-byte VLE insn.  */
      if ((dialect & PPC_OPCODE_VLE) != 0)
        {
          /* Clear buffer so unused bytes will not have garbage in them.  */
          buffer[0] = buffer[1] = buffer[2] = buffer[3] = 0;
          status = (*info->read_memory_func) (memaddr, buffer, 2, info);
          if (status != 0)
            {
              (*info->memory_error_func) (status, memaddr, info);
              return -1;
            }
        }
      else
        {
          (*info->memory_error_func) (status, memaddr, info);
          return -1;
        }
    }

  if (bigendian)
    insn = bfd_getb32 (buffer);
  else
    insn = bfd_getl32 (buffer);

  /* Get the major opcode of the insn.  */
  opcode = NULL;
  insn_is_short = FALSE;
  if ((dialect & PPC_OPCODE_VLE) != 0)
    {
      opcode = lookup_vle (insn);
      if (opcode != NULL)
	insn_is_short = PPC_OP_SE_VLE(opcode->mask);
    }
  if (opcode == NULL)
    opcode = lookup_powerpc (insn, dialect);
  if (opcode == NULL && (dialect & PPC_OPCODE_ANY) != 0)
    opcode = lookup_powerpc (insn, (ppc_cpu_t) -1);

  if (opcode != NULL)
    {
      const unsigned char *opindex;
      const struct powerpc_operand *operand;
      int need_comma;
      int need_paren;
      int skip_optional;

      if (opcode->operands[0] != 0)
	(*info->fprintf_func) (info->stream, "%-7s ", opcode->name);
      else
	(*info->fprintf_func) (info->stream, "%s", opcode->name);

      if (insn_is_short)
        /* The operands will be fetched out of the 16-bit instruction.  */
        insn >>= 16;

      /* Now extract and print the operands.  */
      need_comma = 0;
      need_paren = 0;
      skip_optional = -1;
      for (opindex = opcode->operands; *opindex != 0; opindex++)
	{
	  long value;

	  operand = powerpc_operands + *opindex;

	  /* Operands that are marked FAKE are simply ignored.  We
	     already made sure that the extract function considered
	     the instruction to be valid.  */
	  if ((operand->flags & PPC_OPERAND_FAKE) != 0)
	    continue;

	  /* If all of the optional operands have the value zero,
	     then don't print any of them.  */
	  if ((operand->flags & PPC_OPERAND_OPTIONAL) != 0)
	    {
	      if (skip_optional < 0)
		skip_optional = skip_optional_operands (opindex, insn,
							dialect);
	      if (skip_optional)
		continue;
	    }

	  value = operand_value_powerpc (operand, insn, dialect);

	  if (need_comma)
	    {
	      (*info->fprintf_func) (info->stream, ",");
	      need_comma = 0;
	    }

	  /* Print the operand as directed by the flags.  */
	  if ((operand->flags & PPC_OPERAND_GPR) != 0
	      || ((operand->flags & PPC_OPERAND_GPR_0) != 0 && value != 0))
	    (*info->fprintf_func) (info->stream, "r%ld", value);
	  else if ((operand->flags & PPC_OPERAND_FPR) != 0)
	    (*info->fprintf_func) (info->stream, "f%ld", value);
	  else if ((operand->flags & PPC_OPERAND_VR) != 0)
	    (*info->fprintf_func) (info->stream, "v%ld", value);
	  else if ((operand->flags & PPC_OPERAND_VSR) != 0)
	    (*info->fprintf_func) (info->stream, "vs%ld", value);
	  else if ((operand->flags & PPC_OPERAND_RELATIVE) != 0)
	    (*info->print_address_func) (memaddr + value, info);
	  else if ((operand->flags & PPC_OPERAND_ABSOLUTE) != 0)
	    (*info->print_address_func) ((bfd_vma) value & 0xffffffff, info);
	  else if ((operand->flags & PPC_OPERAND_FSL) != 0)
	    (*info->fprintf_func) (info->stream, "fsl%ld", value);
	  else if ((operand->flags & PPC_OPERAND_FCR) != 0)
	    (*info->fprintf_func) (info->stream, "fcr%ld", value);
	  else if ((operand->flags & PPC_OPERAND_UDI) != 0)
	    (*info->fprintf_func) (info->stream, "%ld", value);
	  else if ((operand->flags & PPC_OPERAND_CR_REG) != 0
		   && (((dialect & PPC_OPCODE_PPC) != 0)
		       || ((dialect & PPC_OPCODE_VLE) != 0)))
	    (*info->fprintf_func) (info->stream, "cr%ld", value);
	  else if (((operand->flags & PPC_OPERAND_CR_BIT) != 0)
		   && (((dialect & PPC_OPCODE_PPC) != 0)
		       || ((dialect & PPC_OPCODE_VLE) != 0)))
	    {
	      static const char *cbnames[4] = { "lt", "gt", "eq", "so" };
	      int cr;
	      int cc;

	      cr = value >> 2;
	      if (cr != 0)
		(*info->fprintf_func) (info->stream, "4*cr%d+", cr);
	      cc = value & 3;
	      (*info->fprintf_func) (info->stream, "%s", cbnames[cc]);
	    }
	  else
	    (*info->fprintf_func) (info->stream, "%d", (int) value);

	  if (need_paren)
	    {
	      (*info->fprintf_func) (info->stream, ")");
	      need_paren = 0;
	    }

	  if ((operand->flags & PPC_OPERAND_PARENS) == 0)
	    need_comma = 1;
	  else
	    {
	      (*info->fprintf_func) (info->stream, "(");
	      need_paren = 1;
	    }
	}

      /* We have found and printed an instruction.
         If it was a short VLE instruction we have more to do.  */
      if (insn_is_short)
        {
          memaddr += 2;
          return 2;
        }
      else
        /* Otherwise, return.  */
        return 4;
    }

  /* We could not find a match.  */
  (*info->fprintf_func) (info->stream, ".long 0x%lx", insn);

  return 4;
}

void
print_ppc_disassembler_options (FILE *stream)
{
  unsigned int i, col;

  fprintf (stream, _("\n\
The following PPC specific disassembler options are supported for use with\n\
the -M switch:\n"));

  for (col = 0, i = 0; i < sizeof (ppc_opts) / sizeof (ppc_opts[0]); i++)
    {
      col += fprintf (stream, " %s,", ppc_opts[i].opt);
      if (col > 66)
	{
	  fprintf (stream, "\n");
	  col = 0;
	}
    }
  fprintf (stream, " 32, 64\n");
}