xref: /netbsd-src/external/gpl3/binutils/dist/ld/emultempl/mmo.em (revision 7788a0781fe6ff2cce37368b4578a7ade0850cb1)
1# This shell script emits a C file. -*- C -*-
2#   Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
3#   Free Software Foundation, Inc.
4#
5# This file is part of the GNU Binutils.
6#
7# This program is free software; you can redistribute it and/or modify
8# it under the terms of the GNU General Public License as published by
9# the Free Software Foundation; either version 3 of the License, or
10# (at your option) any later version.
11#
12# This program is distributed in the hope that it will be useful,
13# but WITHOUT ANY WARRANTY; without even the implied warranty of
14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15# GNU General Public License for more details.
16#
17# You should have received a copy of the GNU General Public License
18# along with this program; if not, write to the Free Software
19# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20# MA 02110-1301, USA.
21#
22
23# This file is sourced from generic.em.
24
25fragment <<EOF
26/* Need to have this macro defined before mmix-elfnmmo, which uses the
27   name for the before_allocation function, defined in ldemul.c (for
28   the mmo "emulation") or in elf32.em (for the elf64mmix
29   "emulation").  */
30#define gldmmo_before_allocation before_allocation_default
31
32/* We include this header *not* because we expect to handle ELF here
33   but because we re-use the map_segments function in elf-generic.em,
34   a file which is rightly somewhat ELF-centric.  But this is only to
35   get a weird testcase right; ld-mmix/bpo-22, forcing ELF to be
36   output from the mmo emulation: -m mmo --oformat elf64-mmix!  */
37#include "elf-bfd.h"
38
39static void gld${EMULATION_NAME}_after_allocation (void);
40EOF
41
42source_em ${srcdir}/emultempl/elf-generic.em
43source_em ${srcdir}/emultempl/mmix-elfnmmo.em
44
45fragment <<EOF
46
47/* Place an orphan section.  We use this to put random SEC_CODE or
48   SEC_READONLY sections right after MMO_TEXT_SECTION_NAME.  Much borrowed
49   from elf32.em.  */
50
51static lang_output_section_statement_type *
52mmo_place_orphan (asection *s,
53		  const char *secname,
54		  int constraint ATTRIBUTE_UNUSED)
55{
56  static struct orphan_save hold_text =
57    {
58      MMO_TEXT_SECTION_NAME,
59      SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE,
60      0, 0, 0, 0
61    };
62  struct orphan_save *place;
63  lang_output_section_statement_type *after;
64  lang_output_section_statement_type *os;
65
66  /* We have nothing to say for anything other than a final link.  */
67  if (link_info.relocatable
68      || (s->flags & (SEC_EXCLUDE | SEC_LOAD)) != SEC_LOAD)
69    return NULL;
70
71  /* Only care for sections we're going to load.  */
72  os = lang_output_section_find (secname);
73
74  /* We have an output section by this name.  Place the section inside it
75     (regardless of whether the linker script lists it as input).  */
76  if (os != NULL)
77    {
78      lang_add_section (&os->children, s, os);
79      return os;
80    }
81
82  /* If this section does not have .text-type section flags or there's no
83     MMO_TEXT_SECTION_NAME, we don't have anything to say.  */
84  if ((s->flags & (SEC_CODE | SEC_READONLY)) == 0)
85    return NULL;
86
87  if (hold_text.os == NULL)
88    hold_text.os = lang_output_section_find (hold_text.name);
89
90  place = &hold_text;
91  if (hold_text.os != NULL)
92    after = hold_text.os;
93  else
94    after = &lang_output_section_statement.head->output_section_statement;
95
96  /* If there's an output section by this name, we'll use it, regardless
97     of section flags, in contrast to what's done in elf32.em.  */
98  os = lang_insert_orphan (s, secname, 0, after, place, NULL, NULL);
99
100  /* We need an output section for .text as a root, so if there was none
101     (might happen with a peculiar linker script such as in "map
102     addresses", map-address.exp), we grab the output section created
103     above.  */
104  if (hold_text.os == NULL)
105    hold_text.os = os;
106
107  return os;
108}
109
110/* Remove the spurious settings of SEC_RELOC that make it to the output at
111   link time.  We are as confused as elflink.h:elf_bfd_final_link, and
112   paper over the bug similarly.  */
113
114static void
115mmo_wipe_sec_reloc_flag (bfd *abfd, asection *sec, void *ptr ATTRIBUTE_UNUSED)
116{
117  bfd_set_section_flags (abfd, sec,
118			 bfd_get_section_flags (abfd, sec) & ~SEC_RELOC);
119}
120
121/* Iterate with bfd_map_over_sections over mmo_wipe_sec_reloc_flag... */
122
123static void
124gld${EMULATION_NAME}_after_allocation (void)
125{
126  bfd_map_over_sections (link_info.output_bfd, mmo_wipe_sec_reloc_flag, NULL);
127  gld${EMULATION_NAME}_map_segments (FALSE);
128}
129
130/* To get on-demand global register allocation right, we need to parse the
131   relocs, like what happens when linking to ELF.  It needs to be done
132   before all input sections are supposed to be present.  When linking to
133   ELF, it's done when reading symbols.  When linking to mmo, we do it
134   when all input files are seen, which is equivalent.  */
135
136static void
137mmo_after_open (void)
138{
139  /* When there's a mismatch between the output format and the emulation
140     (using weird combinations like "-m mmo --oformat elf64-mmix" for
141     example), we'd count relocs twice because they'd also be counted
142     along the usual route for ELF-only linking, which would lead to an
143     internal accounting error.  */
144  if (bfd_get_flavour (link_info.output_bfd) != bfd_target_elf_flavour)
145    {
146      LANG_FOR_EACH_INPUT_STATEMENT (is)
147	{
148	  if (bfd_get_flavour (is->the_bfd) == bfd_target_elf_flavour
149	      && !_bfd_mmix_check_all_relocs (is->the_bfd, &link_info))
150	    einfo ("%X%P: Internal problems scanning %B after opening it",
151		   is->the_bfd);
152	}
153    }
154  after_open_default ();
155}
156EOF
157
158LDEMUL_PLACE_ORPHAN=mmo_place_orphan
159LDEMUL_AFTER_OPEN=mmo_after_open
160