[deliverable/binutils-gdb.git] / bfd / cpu-m68k.c

/* BFD library support routines for architectures.
   Copyright 1990, 1991, 1992, 1993, 1994, 1997, 1998, 2000, 2001, 2002,
   2003, 2004, 2006, 2007 Free Software Foundation, Inc.
   Hacked by Steve Chamberlain of Cygnus Support.

   This file is part of BFD, the Binary File Descriptor library.

   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 3 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., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include "bfd.h"
#include "libbfd.h"
#include "opcode/m68k.h"

static const bfd_arch_info_type *
bfd_m68k_compatible (const bfd_arch_info_type *a,
		     const bfd_arch_info_type *b);

#define N(name, print,d,next)  \
{  32, 32, 8, bfd_arch_m68k, name, "m68k",print,2,d,bfd_m68k_compatible,bfd_default_scan, next, }

static const bfd_arch_info_type arch_info_struct[] =
  {
    N(bfd_mach_m68000,  "m68k:68000", FALSE, &arch_info_struct[1]),
    N(bfd_mach_m68008,  "m68k:68008", FALSE, &arch_info_struct[2]),
    N(bfd_mach_m68010,  "m68k:68010", FALSE, &arch_info_struct[3]),
    N(bfd_mach_m68020,  "m68k:68020", FALSE, &arch_info_struct[4]),
    N(bfd_mach_m68030,  "m68k:68030", FALSE, &arch_info_struct[5]),
    N(bfd_mach_m68040,  "m68k:68040", FALSE, &arch_info_struct[6]),
    N(bfd_mach_m68060,  "m68k:68060", FALSE, &arch_info_struct[7]),
    N(bfd_mach_cpu32,   "m68k:cpu32", FALSE, &arch_info_struct[8]),
    N(bfd_mach_fido,    "m68k:fido",  FALSE, &arch_info_struct[9]),

    /* Various combinations of CF architecture features */
    N(bfd_mach_mcf_isa_a_nodiv, "m68k:isa-a:nodiv",
      FALSE, &arch_info_struct[10]),
    N(bfd_mach_mcf_isa_a, "m68k:isa-a",
      FALSE, &arch_info_struct[11]),
    N(bfd_mach_mcf_isa_a_mac, "m68k:isa-a:mac",
      FALSE, &arch_info_struct[12]),
    N(bfd_mach_mcf_isa_a_emac, "m68k:isa-a:emac",
      FALSE, &arch_info_struct[13]),
    N(bfd_mach_mcf_isa_aplus, "m68k:isa-aplus",
      FALSE, &arch_info_struct[14]),
    N(bfd_mach_mcf_isa_aplus_mac, "m68k:isa-aplus:mac",
      FALSE, &arch_info_struct[15]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:isa-aplus:emac",
      FALSE, &arch_info_struct[16]),
    N(bfd_mach_mcf_isa_b_nousp, "m68k:isa-b:nousp",
      FALSE, &arch_info_struct[17]),
    N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:isa-b:nousp:mac",
      FALSE, &arch_info_struct[18]),
    N(bfd_mach_mcf_isa_b_nousp_emac, "m68k:isa-b:nousp:emac",
      FALSE, &arch_info_struct[19]),
    N(bfd_mach_mcf_isa_b, "m68k:isa-b",
      FALSE, &arch_info_struct[20]),
    N(bfd_mach_mcf_isa_b_mac, "m68k:isa-b:mac",
      FALSE, &arch_info_struct[21]),
    N(bfd_mach_mcf_isa_b_emac, "m68k:isa-b:emac",
      FALSE, &arch_info_struct[22]),
    N(bfd_mach_mcf_isa_b_float, "m68k:isa-b:float",
      FALSE, &arch_info_struct[23]),
    N(bfd_mach_mcf_isa_b_float_mac, "m68k:isa-b:float:mac",
      FALSE, &arch_info_struct[24]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:isa-b:float:emac",
      FALSE, &arch_info_struct[25]),
    N(bfd_mach_mcf_isa_c, "m68k:isa-c",
      FALSE, &arch_info_struct[26]),
    N(bfd_mach_mcf_isa_c_mac, "m68k:isa-c:mac",
      FALSE, &arch_info_struct[27]),
    N(bfd_mach_mcf_isa_c_emac, "m68k:isa-c:emac",
      FALSE, &arch_info_struct[28]),

    /* Legacy names for CF architectures */
    N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[29]),
    N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[30]),
    N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[31]),
    N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[32]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[33]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[34]),
    N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[35]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
      FALSE, &arch_info_struct[36]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
      FALSE, &arch_info_struct[37]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
  };

const bfd_arch_info_type bfd_m68k_arch =
  N(0, "m68k", TRUE, &arch_info_struct[0]);

/* Table indexed by bfd_mach_arch number indicating which
   architectural features are supported.  */
static const unsigned m68k_arch_features[] = 
{
  0,
  m68000|m68881|m68851,
  m68000|m68881|m68851,
  m68010|m68881|m68851,
  m68020|m68881|m68851,
  m68030|m68881|m68851,
  m68040|m68881|m68851,
  m68060|m68881|m68851,
  cpu32|m68881,
  fido_a|m68881,
  mcfisa_a,
  mcfisa_a|mcfhwdiv,
  mcfisa_a|mcfhwdiv|mcfmac,
  mcfisa_a|mcfhwdiv|mcfemac,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfmac,
  mcfisa_a|mcfisa_aa|mcfhwdiv|mcfusp|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_b|mcfusp|cfloat|mcfemac,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp|mcfmac,
  mcfisa_a|mcfhwdiv|mcfisa_c|mcfusp|mcfemac,
};

/* Return the count of bits set in MASK  */
static unsigned
bit_count (unsigned mask)
{
  unsigned ix;

  for (ix = 0; mask; ix++)
    /* Clear the LSB set */
    mask ^= mask & -mask;
  return ix;
}

/* Return the architectural features supported by MACH */

unsigned
bfd_m68k_mach_to_features (int mach)
{
  if ((unsigned)mach
      >= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
    mach = 0;
  return m68k_arch_features[mach];
}

/* Return the bfd machine that most closely represents the
   architectural features.  We find the machine with the smallest
   number of additional features.  If there is no such machine, we
   find the one with the smallest number of missing features.  */

int bfd_m68k_features_to_mach (unsigned features)
{
  int superset = 0, subset = 0;
  unsigned extra = 99, missing = 99;
  unsigned ix;

  for (ix = 0;
       ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
       ix++)
    {
      unsigned this_extra, this_missing;
      
      if (m68k_arch_features[ix] == features)
	return ix;
      this_extra = bit_count (m68k_arch_features[ix] & ~features);
      if (this_extra < extra)
	{
	  extra = this_extra;
	  superset = ix;
	}
      
      this_missing = bit_count (features & ~m68k_arch_features[ix]);
      if (this_missing < missing)
	{
	  missing = this_missing;
	  superset = ix;
	}
    }
  return superset ? superset : subset;
}

static const bfd_arch_info_type *
bfd_m68k_compatible (const bfd_arch_info_type *a,
		     const bfd_arch_info_type *b)
{
  if (a->arch != b->arch)
    return NULL;

  if (a->bits_per_word != b->bits_per_word)
    return NULL;

  if (!a->mach)
    return b;
  if (!b->mach)
    return a;
  
  if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
    /* Merge m68k machine. */
    return a->mach > b->mach ? a : b;
  else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
    {
      /* Merge the machine features.  */
      unsigned features = (bfd_m68k_mach_to_features (a->mach)
			   | bfd_m68k_mach_to_features (b->mach));

      /* CPU32 and Coldfire are incompatible.  */
      if ((~features & (cpu32 | mcfisa_a)) == 0)
	return NULL;

      /* Fido and Coldfire are incompatible.  */
      if ((~features & (fido_a | mcfisa_a)) == 0)
	return NULL;

      /* ISA A+ and ISA B are incompatible.  */
      if ((~features & (mcfisa_aa | mcfisa_b)) == 0)
	return NULL;

      /* ISA B and ISA C are incompatible.  */
      if ((~features & (mcfisa_b | mcfisa_c)) == 0)
	return NULL;

      /* MAC and EMAC code cannot be merged.  */
      if ((~features & (mcfmac | mcfemac)) == 0)
	return NULL;

      /* CPU32 is compatible with Fido except that Fido does not
	 support tbl instructions.  Warn when the user wants to mix
	 the two.  */
      if ((a->mach == bfd_mach_cpu32 && b->mach == bfd_mach_fido)
	  || (a->mach == bfd_mach_fido && b->mach == bfd_mach_cpu32))
	{
	  static int cpu32_fido_mix_warning;
	  if (!cpu32_fido_mix_warning)
	    {
	      cpu32_fido_mix_warning = 1;
	      (*_bfd_error_handler) ("warning: linking CPU32 objects with fido objects");
	    }
	  return bfd_lookup_arch (a->arch,
				  bfd_m68k_features_to_mach (fido_a | m68881));
	}

      return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
    }
  else
    /* They are incompatible.  */
    return NULL;
}
Commit	Line	Data
252b5132	1	/* BFD library support routines for architectures.
3e602632	2	Copyright 1990, 1991, 1992, 1993, 1994, 1997, 1998, 2000, 2001, 2002,
3db64b00	3	2003, 2004, 2006, 2007 Free Software Foundation, Inc.
252b5132 RH	4	Hacked by Steve Chamberlain of Cygnus Support.
252b5132 RH	5
3e602632	6	This file is part of BFD, the Binary File Descriptor library.
252b5132	7
3e602632 NC	8	This program is free software; you can redistribute it and/or modify
3e602632 NC	9	it under the terms of the GNU General Public License as published by
cd123cb7	10	the Free Software Foundation; either version 3 of the License, or
3e602632	11	(at your option) any later version.
252b5132	12
3e602632 NC	13	This program is distributed in the hope that it will be useful,
	14	but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	GNU General Public License for more details.
252b5132	17
3e602632 NC	18	You should have received a copy of the GNU General Public License
3e602632 NC	19	along with this program; if not, write to the Free Software
cd123cb7 NC	20	Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
cd123cb7 NC	21	MA 02110-1301, USA. */
252b5132	22
252b5132	23	#include "sysdep.h"
3db64b00	24	#include "bfd.h"
252b5132	25	#include "libbfd.h"
266abb8f	26	#include "opcode/m68k.h"
252b5132	27
0b2e31dc NS	28	static const bfd_arch_info_type *
	29	bfd_m68k_compatible (const bfd_arch_info_type *a,
	30	const bfd_arch_info_type *b);
	31
252b5132	32	#define N(name, print,d,next) \
0b2e31dc	33	{ 32, 32, 8, bfd_arch_m68k, name, "m68k",print,2,d,bfd_m68k_compatible,bfd_default_scan, next, }
252b5132 RH	34
252b5132 RH	35	static const bfd_arch_info_type arch_info_struct[] =
3cac17ae	36	{
3e602632 NC	37	N(bfd_mach_m68000, "m68k:68000", FALSE, &arch_info_struct[1]),
	38	N(bfd_mach_m68008, "m68k:68008", FALSE, &arch_info_struct[2]),
	39	N(bfd_mach_m68010, "m68k:68010", FALSE, &arch_info_struct[3]),
	40	N(bfd_mach_m68020, "m68k:68020", FALSE, &arch_info_struct[4]),
	41	N(bfd_mach_m68030, "m68k:68030", FALSE, &arch_info_struct[5]),
	42	N(bfd_mach_m68040, "m68k:68040", FALSE, &arch_info_struct[6]),
266abb8f NS	43	N(bfd_mach_m68060, "m68k:68060", FALSE, &arch_info_struct[7]),
266abb8f NS	44	N(bfd_mach_cpu32, "m68k:cpu32", FALSE, &arch_info_struct[8]),
3bdcfdf4	45	N(bfd_mach_fido, "m68k:fido", FALSE, &arch_info_struct[9]),
266abb8f NS	46
266abb8f NS	47	/* Various combinations of CF architecture features */
0b2e31dc	48	N(bfd_mach_mcf_isa_a_nodiv, "m68k:isa-a:nodiv",
266abb8f	49	FALSE, &arch_info_struct[10]),
9840d27e	50	N(bfd_mach_mcf_isa_a, "m68k:isa-a",
266abb8f	51	FALSE, &arch_info_struct[11]),
9840d27e	52	N(bfd_mach_mcf_isa_a_mac, "m68k:isa-a:mac",
266abb8f	53	FALSE, &arch_info_struct[12]),
9840d27e	54	N(bfd_mach_mcf_isa_a_emac, "m68k:isa-a:emac",
266abb8f	55	FALSE, &arch_info_struct[13]),
9840d27e	56	N(bfd_mach_mcf_isa_aplus, "m68k:isa-aplus",
266abb8f	57	FALSE, &arch_info_struct[14]),
9840d27e	58	N(bfd_mach_mcf_isa_aplus_mac, "m68k:isa-aplus:mac",
266abb8f	59	FALSE, &arch_info_struct[15]),
9840d27e	60	N(bfd_mach_mcf_isa_aplus_emac, "m68k:isa-aplus:emac",
266abb8f	61	FALSE, &arch_info_struct[16]),
9840d27e	62	N(bfd_mach_mcf_isa_b_nousp, "m68k:isa-b:nousp",
266abb8f	63	FALSE, &arch_info_struct[17]),
9840d27e	64	N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:isa-b:nousp:mac",
266abb8f	65	FALSE, &arch_info_struct[18]),
9840d27e	66	N(bfd_mach_mcf_isa_b_nousp_emac, "m68k:isa-b:nousp:emac",
266abb8f	67	FALSE, &arch_info_struct[19]),
9840d27e	68	N(bfd_mach_mcf_isa_b, "m68k:isa-b",
266abb8f	69	FALSE, &arch_info_struct[20]),
9840d27e	70	N(bfd_mach_mcf_isa_b_mac, "m68k:isa-b:mac",
266abb8f	71	FALSE, &arch_info_struct[21]),
9840d27e	72	N(bfd_mach_mcf_isa_b_emac, "m68k:isa-b:emac",
266abb8f	73	FALSE, &arch_info_struct[22]),
9840d27e	74	N(bfd_mach_mcf_isa_b_float, "m68k:isa-b:float",
266abb8f	75	FALSE, &arch_info_struct[23]),
9840d27e	76	N(bfd_mach_mcf_isa_b_float_mac, "m68k:isa-b:float:mac",
266abb8f	77	FALSE, &arch_info_struct[24]),
9840d27e KH	78	N(bfd_mach_mcf_isa_b_float_emac, "m68k:isa-b:float:emac",
9840d27e KH	79	FALSE, &arch_info_struct[25]),
9a2e615a NS	80	N(bfd_mach_mcf_isa_c, "m68k:isa-c",
	81	FALSE, &arch_info_struct[26]),
	82	N(bfd_mach_mcf_isa_c_mac, "m68k:isa-c:mac",
	83	FALSE, &arch_info_struct[27]),
	84	N(bfd_mach_mcf_isa_c_emac, "m68k:isa-c:emac",
	85	FALSE, &arch_info_struct[28]),
266abb8f NS	86
266abb8f NS	87	/* Legacy names for CF architectures */
9a2e615a NS	88	N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[29]),
	89	N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[30]),
	90	N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[31]),
	91	N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[32]),
	92	N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[33]),
	93	N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[34]),
	94	N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[35]),
0b2e31dc	95	N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
9a2e615a	96	FALSE, &arch_info_struct[36]),
9840d27e	97	N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
9a2e615a	98	FALSE, &arch_info_struct[37]),
0b2e31dc	99	N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
3cac17ae	100	};
252b5132 RH	101
252b5132 RH	102	const bfd_arch_info_type bfd_m68k_arch =
b34976b6	103	N(0, "m68k", TRUE, &arch_info_struct[0]);
266abb8f NS	104
	105	/* Table indexed by bfd_mach_arch number indicating which
	106	architectural features are supported. */
	107	static const unsigned m68k_arch_features[] =
	108	{
	109	0,
	110	m68000\|m68881\|m68851,
	111	m68000\|m68881\|m68851,
	112	m68010\|m68881\|m68851,
	113	m68020\|m68881\|m68851,
	114	m68030\|m68881\|m68851,
	115	m68040\|m68881\|m68851,
	116	m68060\|m68881\|m68851,
	117	cpu32\|m68881,
3bdcfdf4	118	fido_a\|m68881,
266abb8f NS	119	mcfisa_a,
	120	mcfisa_a\|mcfhwdiv,
	121	mcfisa_a\|mcfhwdiv\|mcfmac,
	122	mcfisa_a\|mcfhwdiv\|mcfemac,
266abb8f NS	123	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp,
	124	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfmac,
	125	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfemac,
	126	mcfisa_a\|mcfhwdiv\|mcfisa_b,
	127	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfmac,
	128	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfemac,
0b2e31dc NS	129	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp,
	130	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfmac,
	131	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfemac,
266abb8f NS	132	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat,
	133	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfmac,
	134	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfemac,
9a2e615a NS	135	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp,
	136	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfmac,
	137	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfemac,
266abb8f NS	138	};
	139
	140	/* Return the count of bits set in MASK */
	141	static unsigned
	142	bit_count (unsigned mask)
	143	{
	144	unsigned ix;
	145
	146	for (ix = 0; mask; ix++)
	147	/* Clear the LSB set */
	148	mask ^= mask & -mask;
	149	return ix;
	150	}
	151
	152	/* Return the architectural features supported by MACH */
	153
	154	unsigned
	155	bfd_m68k_mach_to_features (int mach)
	156	{
	157	if ((unsigned)mach
	158	>= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
	159	mach = 0;
	160	return m68k_arch_features[mach];
	161	}
	162
	163	/* Return the bfd machine that most closely represents the
	164	architectural features. We find the machine with the smallest
	165	number of additional features. If there is no such machine, we
	166	find the one with the smallest number of missing features. */
	167
	168	int bfd_m68k_features_to_mach (unsigned features)
	169	{
	170	int superset = 0, subset = 0;
	171	unsigned extra = 99, missing = 99;
	172	unsigned ix;
	173
	174	for (ix = 0;
	175	ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
	176	ix++)
	177	{
	178	unsigned this_extra, this_missing;
	179
	180	if (m68k_arch_features[ix] == features)
	181	return ix;
	182	this_extra = bit_count (m68k_arch_features[ix] & ~features);
	183	if (this_extra < extra)
	184	{
	185	extra = this_extra;
	186	superset = ix;
	187	}
	188
	189	this_missing = bit_count (features & ~m68k_arch_features[ix]);
	190	if (this_missing < missing)
	191	{
	192	missing = this_missing;
	193	superset = ix;
	194	}
	195	}
	196	return superset ? superset : subset;
	197	}
0b2e31dc NS	198
	199	static const bfd_arch_info_type *
	200	bfd_m68k_compatible (const bfd_arch_info_type *a,
	201	const bfd_arch_info_type *b)
	202	{
	203	if (a->arch != b->arch)
	204	return NULL;
	205
	206	if (a->bits_per_word != b->bits_per_word)
	207	return NULL;
	208
	209	if (!a->mach)
	210	return b;
	211	if (!b->mach)
	212	return a;
	213
	214	if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
	215	/* Merge m68k machine. */
	216	return a->mach > b->mach ? a : b;
9840d27e	217	else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
0b2e31dc	218	{
9840d27e	219	/* Merge the machine features. */
0b2e31dc NS	220	unsigned features = (bfd_m68k_mach_to_features (a->mach)
0b2e31dc NS	221	\| bfd_m68k_mach_to_features (b->mach));
0b2e31dc	222
9840d27e KH	223	/* CPU32 and Coldfire are incompatible. */
	224	if ((~features & (cpu32 \| mcfisa_a)) == 0)
	225	return NULL;
	226
3bdcfdf4 KH	227	/* Fido and Coldfire are incompatible. */
	228	if ((~features & (fido_a \| mcfisa_a)) == 0)
	229	return NULL;
	230
a9d34880 RS	231	/* ISA A+ and ISA B are incompatible. */
	232	if ((~features & (mcfisa_aa \| mcfisa_b)) == 0)
	233	return NULL;
	234
9a2e615a NS	235	/* ISA B and ISA C are incompatible. */
	236	if ((~features & (mcfisa_b \| mcfisa_c)) == 0)
	237	return NULL;
	238
a9d34880 RS	239	/* MAC and EMAC code cannot be merged. */
	240	if ((~features & (mcfmac \| mcfemac)) == 0)
	241	return NULL;
	242
3bdcfdf4 KH	243	/* CPU32 is compatible with Fido except that Fido does not
	244	support tbl instructions. Warn when the user wants to mix
	245	the two. */
	246	if ((a->mach == bfd_mach_cpu32 && b->mach == bfd_mach_fido)
	247	\|\| (a->mach == bfd_mach_fido && b->mach == bfd_mach_cpu32))
	248	{
	249	static int cpu32_fido_mix_warning;
	250	if (!cpu32_fido_mix_warning)
	251	{
	252	cpu32_fido_mix_warning = 1;
	253	(*_bfd_error_handler) ("warning: linking CPU32 objects with fido objects");
	254	}
	255	return bfd_lookup_arch (a->arch,
	256	bfd_m68k_features_to_mach (fido_a \| m68881));
	257	}
	258
a9d34880	259	return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
0b2e31dc NS	260	}
	261	else
	262	/* They are incompatible. */
	263	return NULL;
	264	}