1# This shell script emits a C file. -*- C -*- 2# Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc. 3# 4# This file is part of GLD, the Gnu Linker. 5# 6# This program is free software; you can redistribute it and/or modify 7# it under the terms of the GNU General Public License as published by 8# the Free Software Foundation; either version 2 of the License, or 9# (at your option) any later version. 10# 11# This program is distributed in the hope that it will be useful, 12# but WITHOUT ANY WARRANTY; without even the implied warranty of 13# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14# GNU General Public License for more details. 15# 16# You should have received a copy of the GNU General Public License 17# along with this program; if not, write to the Free Software 18# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19# 20 21# This file is sourced from elf32.em and mmo.em, used to define 22# linker MMIX-specifics common to ELF and MMO. 23 24cat >>e${EMULATION_NAME}.c <<EOF 25/* Need to have this define before mmix-elfnmmo, which includes 26 needrelax.em which uses this name for the before_allocation function, 27 normally defined in elf32.em. */ 28#define gldmmo_before_allocation before_allocation_default 29EOF 30 31. ${srcdir}/emultempl/mmix-elfnmmo.em 32 33cat >>e${EMULATION_NAME}.c <<EOF 34 35/* Find the last output section before given output statement. 36 Used by place_orphan. */ 37 38static asection * 39output_prev_sec_find (lang_output_section_statement_type *os) 40{ 41 asection *s = NULL; 42 lang_statement_union_type *u; 43 lang_output_section_statement_type *lookup; 44 45 for (u = lang_output_section_statement.head; 46 u != (lang_statement_union_type *) NULL; 47 u = lookup->next) 48 { 49 lookup = &u->output_section_statement; 50 if (lookup == os) 51 break; 52 if (lookup->bfd_section != NULL 53 && lookup->bfd_section != bfd_abs_section_ptr 54 && lookup->bfd_section != bfd_com_section_ptr 55 && lookup->bfd_section != bfd_und_section_ptr) 56 s = lookup->bfd_section; 57 } 58 59 if (u == NULL) 60 return NULL; 61 62 return s; 63} 64 65struct orphan_save { 66 lang_output_section_statement_type *os; 67 asection **section; 68 lang_statement_union_type **stmt; 69}; 70 71#define HAVE_SECTION(hold, name) \ 72(hold.os != NULL || (hold.os = lang_output_section_find (name)) != NULL) 73 74/* Place an orphan section. We use this to put random SEC_CODE or 75 SEC_READONLY sections right after MMO_TEXT_SECTION_NAME. Much borrowed 76 from elf32.em. */ 77 78static bfd_boolean 79mmo_place_orphan (lang_input_statement_type *file, asection *s) 80{ 81 static struct orphan_save hold_text; 82 struct orphan_save *place; 83 lang_output_section_statement_type *os; 84 lang_statement_list_type *old; 85 lang_statement_list_type add; 86 asection *snew, **pps, *bfd_section; 87 88 /* We have nothing to say for anything other than a final link. */ 89 if (link_info.relocatable 90 || (bfd_get_section_flags (s->owner, s) 91 & (SEC_EXCLUDE | SEC_LOAD)) != SEC_LOAD) 92 return FALSE; 93 94 /* Only care for sections we're going to load. */ 95 os = lang_output_section_find (bfd_get_section_name (s->owner, s)); 96 97 /* We have an output section by this name. Place the section inside it 98 (regardless of whether the linker script lists it as input). */ 99 if (os != NULL) 100 { 101 lang_add_section (&os->children, s, os, file); 102 return TRUE; 103 } 104 105 /* If this section does not have .text-type section flags or there's no 106 MMO_TEXT_SECTION_NAME, we don't have anything to say. */ 107 if ((bfd_get_section_flags (s->owner, s) & (SEC_CODE | SEC_READONLY)) == 0) 108 return FALSE; 109 110 if (hold_text.os == NULL) 111 hold_text.os = lang_output_section_find (MMO_TEXT_SECTION_NAME); 112 113 place = &hold_text; 114 115 /* If there's an output section by this name, we'll use it, regardless 116 of section flags, in contrast to what's done in elf32.em. */ 117 118 /* Start building a list of statements for this section. 119 First save the current statement pointer. */ 120 old = stat_ptr; 121 122 /* Add the output section statements for this orphan to our own private 123 list, inserting them later into the global statement list. */ 124 stat_ptr = &add; 125 lang_list_init (stat_ptr); 126 127 os = lang_enter_output_section_statement (bfd_get_section_name (s->owner, 128 s), 129 NULL, 0, 130 (etree_type *) NULL, 131 (etree_type *) NULL, 132 (etree_type *) NULL); 133 134 lang_add_section (&os->children, s, os, file); 135 136 lang_leave_output_section_statement 137 ((bfd_vma) 0, "*default*", 138 (struct lang_output_section_phdr_list *) NULL, NULL); 139 140 /* Restore the global list pointer. */ 141 stat_ptr = old; 142 143 snew = os->bfd_section; 144 if (snew == NULL) 145 /* /DISCARD/ section. */ 146 return TRUE; 147 148 /* We need an output section for .text as a root, so if there was none 149 (might happen with a peculiar linker script such as in "map 150 addresses", map-address.exp), we grab the output section created 151 above. */ 152 if (hold_text.os == NULL) 153 { 154 if (os == NULL) 155 return FALSE; 156 hold_text.os = os; 157 } 158 159 bfd_section = place->os->bfd_section; 160 if (place->section == NULL && bfd_section == NULL) 161 bfd_section = output_prev_sec_find (place->os); 162 163 if (place->section != NULL 164 || (bfd_section != NULL 165 && bfd_section != snew)) 166 { 167 /* Shuffle the section to make the output file look neater. This is 168 really only cosmetic. */ 169 if (place->section == NULL) 170 /* Put orphans after the first section on the list. */ 171 place->section = &bfd_section->next; 172 173 /* Unlink the section. */ 174 for (pps = &output_bfd->sections; *pps != snew; pps = &(*pps)->next) 175 ; 176 bfd_section_list_remove (output_bfd, pps); 177 178 /* Now tack it on to the "place->os" section list. */ 179 bfd_section_list_insert (output_bfd, place->section, snew); 180 } 181 place->section = &snew->next; /* Save the end of this list. */ 182 183 if (add.head != NULL) 184 { 185 /* We try to put the output statements in some sort of reasonable 186 order here, because they determine the final load addresses of 187 the orphan sections. */ 188 if (place->stmt == NULL) 189 { 190 /* Put the new statement list right at the head. */ 191 *add.tail = place->os->header.next; 192 place->os->header.next = add.head; 193 } 194 else 195 { 196 /* Put it after the last orphan statement we added. */ 197 *add.tail = *place->stmt; 198 *place->stmt = add.head; 199 } 200 201 /* Fix the global list pointer if we happened to tack our new list 202 at the tail. */ 203 if (*old->tail == add.head) 204 old->tail = add.tail; 205 206 /* Save the end of this list. */ 207 place->stmt = add.tail; 208 } 209 210 return TRUE; 211} 212 213/* Remove the spurious settings of SEC_RELOC that make it to the output at 214 link time. We are as confused as elflink.h:elf_bfd_final_link, and 215 paper over the bug similarly. */ 216 217static void 218mmo_wipe_sec_reloc_flag (bfd *abfd, asection *sec, void *ptr ATTRIBUTE_UNUSED) 219{ 220 bfd_set_section_flags (abfd, sec, 221 bfd_get_section_flags (abfd, sec) & ~SEC_RELOC); 222} 223 224/* Iterate with bfd_map_over_sections over mmo_wipe_sec_reloc_flag... */ 225 226static void 227mmo_finish (void) 228{ 229 bfd_map_over_sections (output_bfd, mmo_wipe_sec_reloc_flag, NULL); 230} 231 232/* To get on-demand global register allocation right, we need to parse the 233 relocs, like what happens when linking to ELF. It needs to be done 234 before all input sections are supposed to be present. When linking to 235 ELF, it's done when reading symbols. When linking to mmo, we do it 236 when all input files are seen, which is equivalent. */ 237 238static void 239mmo_after_open (void) 240{ 241 /* When there's a mismatch between the output format and the emulation 242 (using weird combinations like "-m mmo --oformat elf64-mmix" for 243 example), we'd count relocs twice because they'd also be counted 244 along the usual route for ELF-only linking, which would lead to an 245 internal accounting error. */ 246 if (bfd_get_flavour (output_bfd) != bfd_target_elf_flavour) 247 { 248 LANG_FOR_EACH_INPUT_STATEMENT (is) 249 { 250 if (bfd_get_flavour (is->the_bfd) == bfd_target_elf_flavour 251 && !_bfd_mmix_check_all_relocs (is->the_bfd, &link_info)) 252 einfo ("%X%P: Internal problems scanning %B after opening it", 253 is->the_bfd); 254 } 255 } 256} 257EOF 258 259LDEMUL_PLACE_ORPHAN=mmo_place_orphan 260LDEMUL_FINISH=mmo_finish 261LDEMUL_AFTER_OPEN=mmo_after_open 262