aboutsummaryrefslogtreecommitdiff
path: root/ld/emultempl/cr16elf.em
blob: fe5ee1da9c704d014558ff33859ff8adea88bd33 (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
# This shell script emits a C file. -*- C -*-
# Copyright (C) 2007-2022 Free Software Foundation, Inc.
# Contributed by M R Swami Reddy <MR.Swami.Reddy@nsc.com>
#
# 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 elf.em, and defines extra cr16-elf
# specific routines.
#
fragment <<EOF

#include "ldctor.h"
#include "elf32-cr16.h"

static void check_sections (bfd *, asection *, void *);


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

static void
cr16_elf_after_open (void)
{
  /* Call the standard elf routine.  */
  gld${EMULATION_NAME}_after_open ();

  if (command_line.embedded_relocs
      && !bfd_link_relocatable (&link_info))
    {
      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%P: %pB: all input objects must be COFF or ELF "
		     "for --embedded-relocs\n"));

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

	  /* 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 (abfd, ".emreloc");
	      if (relsec == NULL
		  || !bfd_set_section_flags (relsec, (SEC_ALLOC
						      | SEC_LOAD
						      | SEC_HAS_CONTENTS
						      | SEC_IN_MEMORY))
		  || !bfd_set_section_alignment (relsec, 2)
		  || !bfd_set_section_size (relsec, datasec->reloc_count * 8))
		einfo (_("%F%P: %pB: 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);
	}
    }
}

/* 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 ((strncmp (bfd_section_name (sec), ".data.rel", 9) == 0)
      && sec != datasec
      && sec->reloc_count == 0 )
    einfo (_("%X%P: %pB: section %s has relocs; can not use --embedded-relocs\n"),
	   abfd, bfd_section_name (sec));
}

static void
cr16elf_after_parse (void)
{
  /* Always behave as if called with --sort-common command line
     option.
     This is to emulate the CRTools' method of keeping variables
     of different alignment in separate sections.  */
  config.sort_common = true;

  /* Don't create a demand-paged executable, since this feature isn't
     meaninful in CR16 embedded systems. Moreover, when magic_demand_paged
     is true the link sometimes fails.  */
  config.magic_demand_paged = false;

  ldelf_after_parse ();
}

/* This is called after the sections have been attached to output
   sections, but before any sizes or addresses have been set.  */

static void
cr16elf_before_allocation (void)
{
  /* Call the default first.  */
  gld${EMULATION_NAME}_before_allocation ();

  if (command_line.embedded_relocs
      && (!bfd_link_relocatable (&link_info)))
    {

      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.rel");

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

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

	  if (! bfd_cr16_elf32_create_embedded_relocs (abfd, &link_info,
						       datasec, relsec,
						       &errmsg))
	    {
	      if (errmsg == NULL)
		einfo (_("%X%P: %pB: can not create runtime reloc information: %E\n"),
		       abfd);
	      else
		einfo (_("%X%P: %pB: can not create runtime reloc information: %s\n"),
		       abfd, errmsg);
	    }
	}
    }

  /* Enable relaxation by default if the "--no-relax" option was not
     specified.  This is done here instead of in the before_parse hook
     because there is a check in main() to prohibit use of --relax and
     -r together.  */
  if (RELAXATION_DISABLED_BY_DEFAULT)
    ENABLE_RELAXATION;
}

EOF

# Put these extra cr16-elf routines in ld_${EMULATION_NAME}_emulation
#
LDEMUL_AFTER_OPEN=cr16_elf_after_open
LDEMUL_AFTER_PARSE=cr16elf_after_parse
LDEMUL_BEFORE_ALLOCATION=cr16elf_before_allocation