summaryrefslogtreecommitdiffstats
path: root/binutils-2.25/ld/emultempl/m68kelf.em
blob: c5cfe77b2e1bfa019498c23ecc9e24017701a9e0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
# This shell script emits a C file. -*- C -*-
#   Copyright (C) 2000-2014 Free Software Foundation, Inc.
#   Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em
#
# This file is part of the GNU Binutils.
#
# 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.


# This file is sourced from elf32.em, and defines some extra routines for m68k
# embedded systems using ELF and for some other systems using m68k ELF.  While
# it is sourced from elf32.em for all m68k ELF configurations, here we include
# only the features we want depending on the configuration.

case ${target} in
  m68*-*-elf)
    echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c
    ;;
esac

case ${target} in
  *-linux*)
# Don't use multi-GOT by default due to glibc linker's assumption
# that GOT pointer points to GOT[0].
#   got_handling_target_default=GOT_HANDLING_MULTIGOT
    got_handling_target_default=GOT_HANDLING_SINGLE
    ;;
  *)
    got_handling_target_default=GOT_HANDLING_SINGLE
    ;;
esac

fragment <<EOF

#define GOT_HANDLING_SINGLE   (0)
#define GOT_HANDLING_NEGATIVE (1)
#define GOT_HANDLING_MULTIGOT (2)
#define GOT_HANDLING_TARGET_DEFAULT ${got_handling_target_default}

/* How to generate GOT.  */
static int got_handling = GOT_HANDLING_DEFAULT;

#ifdef SUPPORT_EMBEDDED_RELOCS
static void check_sections (bfd *, asection *, void *);
#endif

/* This function is run after all the input files have been opened.  */

static void
m68k_elf_after_open (void)
{
  /* Call the standard elf routine.  */
  gld${EMULATION_NAME}_after_open ();

#ifdef SUPPORT_EMBEDDED_RELOCS
  if (command_line.embedded_relocs
      && (! link_info.relocatable))
    {
      bfd *abfd;

      /* In the embedded relocs mode we create a .emreloc section for each
	 input file with a nonzero .data section.  The BFD backend will fill in
	 these sections with magic numbers which can be used to relocate the
	 data section at run time.  */
      for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link.next)
	{
	  asection *datasec;

	  /* As first-order business, make sure that each input BFD is either
	     COFF or ELF.  We need to call a special BFD backend function to
	     generate the embedded relocs, and we have such functions only for
	     COFF and ELF.  */
	  if (bfd_get_flavour (abfd) != bfd_target_coff_flavour
	      && bfd_get_flavour (abfd) != bfd_target_elf_flavour)
	    einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n");

	  datasec = bfd_get_section_by_name (abfd, ".data");

	  /* Note that we assume that the reloc_count field has already
	     been set up.  We could call bfd_get_reloc_upper_bound, but
	     that returns the size of a memory buffer rather than a reloc
	     count.  We do not want to call bfd_canonicalize_reloc,
	     because although it would always work it would force us to
	     read in the relocs into BFD canonical form, which would waste
	     a significant amount of time and memory.  */
	  if (datasec != NULL && datasec->reloc_count > 0)
	    {
	      asection *relsec;

	      relsec = bfd_make_section_with_flags (abfd, ".emreloc",
						    (SEC_ALLOC
						    | SEC_LOAD
						    | SEC_HAS_CONTENTS
						    | SEC_IN_MEMORY));
	      if (relsec == NULL
		  || ! bfd_set_section_alignment (abfd, relsec, 2)
		  || ! bfd_set_section_size (abfd, relsec,
					     datasec->reloc_count * 12))
		einfo ("%F%B: can not create .emreloc section: %E\n");
	    }

	  /* Double check that all other data sections are empty, as is
	     required for embedded PIC code.  */
	  bfd_map_over_sections (abfd, check_sections, datasec);
	}
    }
#endif /* SUPPORT_EMBEDDED_RELOCS */
}

#ifdef SUPPORT_EMBEDDED_RELOCS
/* Check that of the data sections, only the .data section has
   relocs.  This is called via bfd_map_over_sections.  */

static void
check_sections (bfd *abfd, asection *sec, void *datasec)
{
  if ((bfd_get_section_flags (abfd, sec) & SEC_DATA)
      && sec != datasec
      && sec->reloc_count != 0)
    einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n",
	   abfd, bfd_get_section_name (abfd, sec));
}

#endif /* SUPPORT_EMBEDDED_RELOCS */

/* This function is called after the section sizes and offsets have
   been set.  */

static void
m68k_elf_after_allocation (void)
{
  /* Call the standard elf routine.  */
  gld${EMULATION_NAME}_after_allocation ();

#ifdef SUPPORT_EMBEDDED_RELOCS
  if (command_line.embedded_relocs
      && (! link_info.relocatable))
    {
      bfd *abfd;

      /* If we are generating embedded relocs, call a special BFD backend
	 routine to do the work.  */
      for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link.next)
	{
	  asection *datasec, *relsec;
	  char *errmsg;

	  datasec = bfd_get_section_by_name (abfd, ".data");

	  if (datasec == NULL || datasec->reloc_count == 0)
	    continue;

	  relsec = bfd_get_section_by_name (abfd, ".emreloc");
	  ASSERT (relsec != NULL);

	  if (bfd_get_flavour (abfd) == bfd_target_coff_flavour)
	    {
	      if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info,
							  datasec, relsec,
							  &errmsg))
		{
		  if (errmsg == NULL)
		    einfo ("%B%X: can not create runtime reloc information: %E\n",
			   abfd);
		  else
		    einfo ("%X%B: can not create runtime reloc information: %s\n",
			   abfd, errmsg);
		}
	    }
	  else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
	    {
	      if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info,
							   datasec, relsec,
							   &errmsg))
		{
		  if (errmsg == NULL)
		    einfo ("%B%X: can not create runtime reloc information: %E\n",
			   abfd);
		  else
		    einfo ("%X%B: can not create runtime reloc information: %s\n",
			   abfd, errmsg);
		}
	    }
	  else
	    abort ();
	}
    }
#endif /* SUPPORT_EMBEDDED_RELOCS */
}

/* This is a convenient point to tell BFD about target specific flags.
   After the output has been created, but before inputs are read.  */

static void
elf_m68k_create_output_section_statements (void)
{
  bfd_elf_m68k_set_target_options (&link_info, got_handling);
}

EOF

# Define some shell vars to insert bits of code into the standard elf
# parse_args and list_options functions.
#
PARSE_AND_LIST_PROLOGUE='
#define OPTION_GOT	301
'

PARSE_AND_LIST_LONGOPTS='
  { "got", required_argument, NULL, OPTION_GOT},
'

PARSE_AND_LIST_OPTIONS='
  fprintf (file, _("  --got=<type>                Specify GOT handling scheme\n"));
'

PARSE_AND_LIST_ARGS_CASES='
    case OPTION_GOT:
      if (strcmp (optarg, "target") == 0)
        got_handling = GOT_HANDLING_TARGET_DEFAULT;
      else if (strcmp (optarg, "single") == 0)
        got_handling = 0;
      else if (strcmp (optarg, "negative") == 0)
        got_handling = 1;
      else if (strcmp (optarg, "multigot") == 0)
        got_handling = 2;
      else
        einfo (_("Unrecognized --got argument '\''%s'\''.\n"), optarg);
      break;
'

# We have our own after_open and after_allocation functions, but they call
# the standard routines, so give them a different name.
LDEMUL_AFTER_OPEN=m68k_elf_after_open
LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation
LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=elf_m68k_create_output_section_statements