[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, 2005, 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]),
    N(bfd_mach_mcf_isa_c_nodiv, "m68k:isa-c:nodiv",
      FALSE, &arch_info_struct[29]),
    N(bfd_mach_mcf_isa_c_nodiv_mac, "m68k:isa-c:nodiv:mac",
      FALSE, &arch_info_struct[30]),
    N(bfd_mach_mcf_isa_c_nodiv_emac, "m68k:isa-c:nodiv:emac",
      FALSE, &arch_info_struct[31]),

    /* Legacy names for CF architectures */
    N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[32]),
    N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[33]),
    N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[34]),
    N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[35]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[36]),
    N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[37]),
    N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[38]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
      FALSE, &arch_info_struct[39]),
    N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
      FALSE, &arch_info_struct[40]),
    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,
  mcfisa_a|mcfisa_c|mcfusp,
  mcfisa_a|mcfisa_c|mcfusp|mcfmac,
  mcfisa_a|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,
aa820537	3	2003, 2004, 2005, 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]),
8d100c32 KH	86	N(bfd_mach_mcf_isa_c_nodiv, "m68k:isa-c:nodiv",
	87	FALSE, &arch_info_struct[29]),
	88	N(bfd_mach_mcf_isa_c_nodiv_mac, "m68k:isa-c:nodiv:mac",
	89	FALSE, &arch_info_struct[30]),
	90	N(bfd_mach_mcf_isa_c_nodiv_emac, "m68k:isa-c:nodiv:emac",
	91	FALSE, &arch_info_struct[31]),
266abb8f NS	92
266abb8f NS	93	/* Legacy names for CF architectures */
8d100c32 KH	94	N(bfd_mach_mcf_isa_a_nodiv, "m68k:5200", FALSE, &arch_info_struct[32]),
	95	N(bfd_mach_mcf_isa_a_mac,"m68k:5206e", FALSE, &arch_info_struct[33]),
	96	N(bfd_mach_mcf_isa_a_mac, "m68k:5307", FALSE, &arch_info_struct[34]),
	97	N(bfd_mach_mcf_isa_b_nousp_mac, "m68k:5407", FALSE, &arch_info_struct[35]),
	98	N(bfd_mach_mcf_isa_aplus_emac, "m68k:528x", FALSE, &arch_info_struct[36]),
	99	N(bfd_mach_mcf_isa_aplus_emac, "m68k:521x", FALSE, &arch_info_struct[37]),
	100	N(bfd_mach_mcf_isa_a_emac, "m68k:5249", FALSE, &arch_info_struct[38]),
0b2e31dc	101	N(bfd_mach_mcf_isa_b_float_emac, "m68k:547x",
8d100c32	102	FALSE, &arch_info_struct[39]),
9840d27e	103	N(bfd_mach_mcf_isa_b_float_emac, "m68k:548x",
8d100c32	104	FALSE, &arch_info_struct[40]),
0b2e31dc	105	N(bfd_mach_mcf_isa_b_float_emac, "m68k:cfv4e", FALSE, 0),
3cac17ae	106	};
252b5132 RH	107
252b5132 RH	108	const bfd_arch_info_type bfd_m68k_arch =
b34976b6	109	N(0, "m68k", TRUE, &arch_info_struct[0]);
266abb8f NS	110
	111	/* Table indexed by bfd_mach_arch number indicating which
	112	architectural features are supported. */
	113	static const unsigned m68k_arch_features[] =
	114	{
	115	0,
	116	m68000\|m68881\|m68851,
	117	m68000\|m68881\|m68851,
	118	m68010\|m68881\|m68851,
	119	m68020\|m68881\|m68851,
	120	m68030\|m68881\|m68851,
	121	m68040\|m68881\|m68851,
	122	m68060\|m68881\|m68851,
	123	cpu32\|m68881,
3bdcfdf4	124	fido_a\|m68881,
266abb8f NS	125	mcfisa_a,
	126	mcfisa_a\|mcfhwdiv,
	127	mcfisa_a\|mcfhwdiv\|mcfmac,
	128	mcfisa_a\|mcfhwdiv\|mcfemac,
266abb8f NS	129	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp,
	130	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfmac,
	131	mcfisa_a\|mcfisa_aa\|mcfhwdiv\|mcfusp\|mcfemac,
	132	mcfisa_a\|mcfhwdiv\|mcfisa_b,
	133	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfmac,
	134	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfemac,
0b2e31dc NS	135	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp,
	136	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfmac,
	137	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|mcfemac,
266abb8f NS	138	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat,
	139	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfmac,
	140	mcfisa_a\|mcfhwdiv\|mcfisa_b\|mcfusp\|cfloat\|mcfemac,
9a2e615a NS	141	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp,
	142	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfmac,
	143	mcfisa_a\|mcfhwdiv\|mcfisa_c\|mcfusp\|mcfemac,
8d100c32 KH	144	mcfisa_a\|mcfisa_c\|mcfusp,
	145	mcfisa_a\|mcfisa_c\|mcfusp\|mcfmac,
	146	mcfisa_a\|mcfisa_c\|mcfusp\|mcfemac,
266abb8f NS	147	};
	148
	149	/* Return the count of bits set in MASK */
	150	static unsigned
	151	bit_count (unsigned mask)
	152	{
	153	unsigned ix;
	154
	155	for (ix = 0; mask; ix++)
	156	/* Clear the LSB set */
	157	mask ^= mask & -mask;
	158	return ix;
	159	}
	160
	161	/* Return the architectural features supported by MACH */
	162
	163	unsigned
	164	bfd_m68k_mach_to_features (int mach)
	165	{
	166	if ((unsigned)mach
	167	>= sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]))
	168	mach = 0;
	169	return m68k_arch_features[mach];
	170	}
	171
	172	/* Return the bfd machine that most closely represents the
	173	architectural features. We find the machine with the smallest
	174	number of additional features. If there is no such machine, we
	175	find the one with the smallest number of missing features. */
	176
	177	int bfd_m68k_features_to_mach (unsigned features)
	178	{
	179	int superset = 0, subset = 0;
	180	unsigned extra = 99, missing = 99;
	181	unsigned ix;
	182
	183	for (ix = 0;
	184	ix != sizeof (m68k_arch_features) / sizeof (m68k_arch_features[0]);
	185	ix++)
	186	{
	187	unsigned this_extra, this_missing;
	188
	189	if (m68k_arch_features[ix] == features)
	190	return ix;
	191	this_extra = bit_count (m68k_arch_features[ix] & ~features);
	192	if (this_extra < extra)
	193	{
	194	extra = this_extra;
	195	superset = ix;
	196	}
	197
	198	this_missing = bit_count (features & ~m68k_arch_features[ix]);
	199	if (this_missing < missing)
	200	{
	201	missing = this_missing;
	202	superset = ix;
	203	}
	204	}
	205	return superset ? superset : subset;
	206	}
0b2e31dc NS	207
	208	static const bfd_arch_info_type *
	209	bfd_m68k_compatible (const bfd_arch_info_type *a,
	210	const bfd_arch_info_type *b)
	211	{
	212	if (a->arch != b->arch)
	213	return NULL;
	214
	215	if (a->bits_per_word != b->bits_per_word)
	216	return NULL;
	217
	218	if (!a->mach)
	219	return b;
	220	if (!b->mach)
	221	return a;
	222
	223	if (a->mach <= bfd_mach_m68060 && b->mach <= bfd_mach_m68060)
	224	/* Merge m68k machine. */
	225	return a->mach > b->mach ? a : b;
9840d27e	226	else if (a->mach >= bfd_mach_cpu32 && b->mach >= bfd_mach_cpu32)
0b2e31dc	227	{
9840d27e	228	/* Merge the machine features. */
0b2e31dc NS	229	unsigned features = (bfd_m68k_mach_to_features (a->mach)
0b2e31dc NS	230	\| bfd_m68k_mach_to_features (b->mach));
0b2e31dc	231
9840d27e KH	232	/* CPU32 and Coldfire are incompatible. */
	233	if ((~features & (cpu32 \| mcfisa_a)) == 0)
	234	return NULL;
	235
3bdcfdf4 KH	236	/* Fido and Coldfire are incompatible. */
	237	if ((~features & (fido_a \| mcfisa_a)) == 0)
	238	return NULL;
	239
a9d34880 RS	240	/* ISA A+ and ISA B are incompatible. */
	241	if ((~features & (mcfisa_aa \| mcfisa_b)) == 0)
	242	return NULL;
	243
9a2e615a NS	244	/* ISA B and ISA C are incompatible. */
	245	if ((~features & (mcfisa_b \| mcfisa_c)) == 0)
	246	return NULL;
	247
a9d34880 RS	248	/* MAC and EMAC code cannot be merged. */
	249	if ((~features & (mcfmac \| mcfemac)) == 0)
	250	return NULL;
	251
3bdcfdf4 KH	252	/* CPU32 is compatible with Fido except that Fido does not
	253	support tbl instructions. Warn when the user wants to mix
	254	the two. */
	255	if ((a->mach == bfd_mach_cpu32 && b->mach == bfd_mach_fido)
	256	\|\| (a->mach == bfd_mach_fido && b->mach == bfd_mach_cpu32))
	257	{
	258	static int cpu32_fido_mix_warning;
	259	if (!cpu32_fido_mix_warning)
	260	{
	261	cpu32_fido_mix_warning = 1;
	262	(*_bfd_error_handler) ("warning: linking CPU32 objects with fido objects");
	263	}
	264	return bfd_lookup_arch (a->arch,
	265	bfd_m68k_features_to_mach (fido_a \| m68881));
	266	}
	267
a9d34880	268	return bfd_lookup_arch (a->arch, bfd_m68k_features_to_mach (features));
0b2e31dc NS	269	}
	270	else
	271	/* They are incompatible. */
	272	return NULL;
	273	}