1# This shell script emits a C file. -*- C -*-
2#   Copyright 1991, 1993, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
3#   2004, 2005
4#   Free Software Foundation, Inc.
5#
6# This file is part of GLD, the Gnu Linker.
7#
8# This program is free software; you can redistribute it and/or modify
9# it under the terms of the GNU General Public License as published by
10# the Free Software Foundation; either version 2 of the License, or
11# (at your option) any later version.
12#
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.
17#
18# You should have received a copy of the GNU General Public License
19# along with this program; if not, write to the Free Software
20# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.
21#
22
23# This file is sourced from elf32.em, and defines extra arm-elf
24# specific routines.
25#
26test -z "$TARGET2_TYPE" && TARGET2_TYPE="rel"
27cat >>e${EMULATION_NAME}.c <<EOF
28
29#include "elf/arm.h"
30
31static char *thumb_entry_symbol = NULL;
32static bfd *bfd_for_interwork;
33static int byteswap_code = 0;
34static int target1_is_rel = 0${TARGET1_IS_REL};
35static char *target2_type = "${TARGET2_TYPE}";
36static int fix_v4bx = 0;
37static int use_blx = 0;
38
39static void
40gld${EMULATION_NAME}_before_parse (void)
41{
42#ifndef TARGET_			/* I.e., if not generic.  */
43  ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
44#endif /* not TARGET_ */
45  config.dynamic_link = ${DYNAMIC_LINK-TRUE};
46  config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
47}
48
49static void
50arm_elf_after_open (void)
51{
52  if (strstr (bfd_get_target (output_bfd), "arm") == NULL)
53    {
54      /* The arm backend needs special fields in the output hash structure.
55	 These will only be created if the output format is an arm format,
56	 hence we do not support linking and changing output formats at the
57	 same time.  Use a link followed by objcopy to change output formats.  */
58      einfo ("%F%X%P: error: cannot change output format whilst linking ARM binaries\n");
59      return;
60    }
61
62  {
63    LANG_FOR_EACH_INPUT_STATEMENT (is)
64      {
65	bfd_elf32_arm_add_glue_sections_to_bfd (is->the_bfd, & link_info);
66      }
67  }
68
69  /* Call the standard elf routine.  */
70  gld${EMULATION_NAME}_after_open ();
71}
72
73static void
74arm_elf_set_bfd_for_interworking (lang_statement_union_type *statement)
75{
76  if (statement->header.type == lang_input_section_enum)
77    {
78      asection *i = statement->input_section.section;
79
80      if (!((lang_input_statement_type *) i->owner->usrdata)->just_syms_flag
81	  && (i->flags & SEC_EXCLUDE) == 0)
82	{
83	  asection *output_section = i->output_section;
84
85	  ASSERT (output_section->owner == output_bfd);
86
87	  /* Don't attach the interworking stubs to a dynamic object, to
88	     an empty section, etc.  */
89	  if ((output_section->flags & SEC_HAS_CONTENTS) != 0
90	      && (i->flags & SEC_NEVER_LOAD) == 0
91	      && ! (i->owner->flags & DYNAMIC)
92	      && ! i->owner->output_has_begun)
93	    {
94	      bfd_for_interwork = i->owner;
95	      bfd_for_interwork->output_has_begun = TRUE;
96	    }
97	}
98    }
99}
100
101static void
102arm_elf_before_allocation (void)
103{
104  bfd *tem;
105
106  /* Call the standard elf routine.  */
107  gld${EMULATION_NAME}_before_allocation ();
108
109  if (link_info.input_bfds != NULL)
110    {
111      /* The interworking bfd must be the last one in the link.  */
112      bfd_for_interwork = NULL;
113      for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
114	tem->output_has_begun = FALSE;
115
116      lang_for_each_statement (arm_elf_set_bfd_for_interworking);
117      for (tem = link_info.input_bfds; tem != NULL; tem = tem->link_next)
118	tem->output_has_begun = FALSE;
119
120      /* If bfd_for_interwork is NULL, then there are no loadable sections
121	 with real contents to be linked, so we are not going to have to
122	 create any interworking stubs, so it is OK not to call
123	 bfd_elf32_arm_get_bfd_for_interworking.  */
124      if (bfd_for_interwork != NULL)
125	bfd_elf32_arm_get_bfd_for_interworking (bfd_for_interwork, &link_info);
126    }
127  /* We should be able to set the size of the interworking stub section.  */
128
129  /* Here we rummage through the found bfds to collect glue information.  */
130  /* FIXME: should this be based on a command line option? krk@cygnus.com  */
131  {
132    LANG_FOR_EACH_INPUT_STATEMENT (is)
133      {
134	if (!bfd_elf32_arm_process_before_allocation (is->the_bfd, & link_info,
135						      byteswap_code))
136	  {
137	    /* xgettext:c-format */
138	    einfo (_("Errors encountered processing file %s"), is->filename);
139	  }
140      }
141  }
142
143  /* We have seen it all. Allocate it, and carry on.  */
144  bfd_elf32_arm_allocate_interworking_sections (& link_info);
145}
146
147static void
148arm_elf_finish (void)
149{
150  struct bfd_link_hash_entry * h;
151
152  /* Call the elf32.em routine.  */
153  gld${EMULATION_NAME}_finish ();
154
155  if (thumb_entry_symbol)
156    {
157      h = bfd_link_hash_lookup (link_info.hash, thumb_entry_symbol,
158				FALSE, FALSE, TRUE);
159    }
160  else
161    {
162      struct elf_link_hash_entry * eh;
163
164      if (!entry_symbol.name)
165	return;
166
167      h = bfd_link_hash_lookup (link_info.hash, entry_symbol.name,
168				FALSE, FALSE, TRUE);
169      eh = (struct elf_link_hash_entry *)h;
170      if (!h || ELF_ST_TYPE(eh->type) != STT_ARM_TFUNC)
171	return;
172    }
173
174
175  if (h != (struct bfd_link_hash_entry *) NULL
176      && (h->type == bfd_link_hash_defined
177	  || h->type == bfd_link_hash_defweak)
178      && h->u.def.section->output_section != NULL)
179    {
180      static char buffer[32];
181      bfd_vma val;
182
183      /* Special procesing is required for a Thumb entry symbol.  The
184	 bottom bit of its address must be set.  */
185      val = (h->u.def.value
186	     + bfd_get_section_vma (output_bfd,
187				    h->u.def.section->output_section)
188	     + h->u.def.section->output_offset);
189
190      val |= 1;
191
192      /* Now convert this value into a string and store it in entry_symbol
193	 where the lang_finish() function will pick it up.  */
194      buffer[0] = '0';
195      buffer[1] = 'x';
196
197      sprintf_vma (buffer + 2, val);
198
199      if (thumb_entry_symbol != NULL && entry_symbol.name != NULL
200	  && entry_from_cmdline)
201	einfo (_("%P: warning: '--thumb-entry %s' is overriding '-e %s'\n"),
202	       thumb_entry_symbol, entry_symbol.name);
203      entry_symbol.name = buffer;
204    }
205  else
206    einfo (_("%P: warning: connot find thumb start symbol %s\n"),
207	   thumb_entry_symbol);
208}
209
210/* This is a convenitent point to tell BFD about target specific flags.
211   After the output has been created, but before inputs are read.  */
212static void
213arm_elf_create_output_section_statements (void)
214{
215  bfd_elf32_arm_set_target_relocs (&link_info, target1_is_rel, target2_type,
216                                   fix_v4bx, use_blx);
217}
218
219EOF
220
221# Define some shell vars to insert bits of code into the standard elf
222# parse_args and list_options functions.
223#
224PARSE_AND_LIST_PROLOGUE='
225#define OPTION_THUMB_ENTRY		301
226#define OPTION_BE8			302
227#define OPTION_TARGET1_REL		303
228#define OPTION_TARGET1_ABS		304
229#define OPTION_TARGET2			305
230#define OPTION_FIX_V4BX			306
231#define OPTION_USE_BLX			307
232'
233
234PARSE_AND_LIST_SHORTOPTS=p
235
236PARSE_AND_LIST_LONGOPTS='
237  { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
238  { "thumb-entry", required_argument, NULL, OPTION_THUMB_ENTRY},
239  { "be8", no_argument, NULL, OPTION_BE8},
240  { "target1-rel", no_argument, NULL, OPTION_TARGET1_REL},
241  { "target1-abs", no_argument, NULL, OPTION_TARGET1_ABS},
242  { "target2", required_argument, NULL, OPTION_TARGET2},
243  { "fix-v4bx", no_argument, NULL, OPTION_FIX_V4BX},
244  { "use-blx", no_argument, NULL, OPTION_USE_BLX},
245'
246
247PARSE_AND_LIST_OPTIONS='
248  fprintf (file, _("     --thumb-entry=<sym>      Set the entry point to be Thumb symbol <sym>\n"));
249  fprintf (file, _("     --be8                    Oputput BE8 format image\n"));
250  fprintf (file, _("     --target1=rel            Interpret R_ARM_TARGET1 as R_ARM_REL32\n"));
251  fprintf (file, _("     --target1=abs            Interpret R_ARM_TARGET1 as R_ARM_ABS32\n"));
252  fprintf (file, _("     --target2=<type>         Specify definition of R_ARM_TARGET2\n"));
253  fprintf (file, _("     --fix-v4bx               Rewrite BX rn as MOV pc, rn for ARMv4\n"));
254  fprintf (file, _("     --use-blx                Enable use of BLX instructions\n"));
255'
256
257PARSE_AND_LIST_ARGS_CASES='
258    case '\'p\'':
259      /* Only here for backwards compatibility.  */
260      break;
261
262    case OPTION_THUMB_ENTRY:
263      thumb_entry_symbol = optarg;
264      break;
265
266    case OPTION_BE8:
267      byteswap_code = 1;
268      break;
269
270    case OPTION_TARGET1_REL:
271      target1_is_rel = 1;
272      break;
273
274    case OPTION_TARGET1_ABS:
275      target1_is_rel = 0;
276      break;
277
278    case OPTION_TARGET2:
279      target2_type = optarg;
280      break;
281
282    case OPTION_FIX_V4BX:
283      fix_v4bx = 1;
284      break;
285
286    case OPTION_USE_BLX:
287      use_blx = 1;
288      break;
289'
290
291# We have our own after_open and before_allocation functions, but they call
292# the standard routines, so give them a different name.
293LDEMUL_AFTER_OPEN=arm_elf_after_open
294LDEMUL_BEFORE_ALLOCATION=arm_elf_before_allocation
295LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=arm_elf_create_output_section_statements
296
297# Replace the elf before_parse function with our own.
298LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
299
300# Call the extra arm-elf function
301LDEMUL_FINISH=arm_elf_finish
302