1 # This shell script emits a C file. -*- C -*- 2 # Copyright (C) 2013-2014 Free Software Foundation, Inc. 3 # 4 # This file is part of GNU Binutils. 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 3 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., 51 Franklin Street - Fifth Floor, Boston, 19 # MA 02110-1301, USA. 20 # 21 22 # This file is sourced from elf32.em, and defines extra Nios II ELF 23 # specific routines. Taken from metagelf.em. 24 # 25 fragment <<EOF 26 27 #include "ldctor.h" 28 #include "elf32-nios2.h" 29 30 31 /* Fake input file for stubs. */ 32 static lang_input_statement_type *stub_file; 33 34 /* Whether we need to call nios2_layout_sections_again. */ 35 static int need_laying_out = 0; 36 37 38 /* This is called before the input files are opened. We create a new 39 fake input file to hold the stub sections. */ 40 41 static void 42 nios2elf_create_output_section_statements (void) 43 { 44 extern const bfd_target nios2_elf32_le_vec, nios2_elf32_be_vec; 45 46 if (link_info.output_bfd->xvec != &nios2_elf32_le_vec 47 && link_info.output_bfd->xvec != &nios2_elf32_be_vec) 48 return; 49 50 /* If --no-relax was not explicitly specified by the user, enable 51 relaxation. If it's not enabled (either explicitly or by default), 52 we're done, as we won't need to create any stubs. */ 53 if (!link_info.relocatable && RELAXATION_DISABLED_BY_DEFAULT) 54 ENABLE_RELAXATION; 55 if (!RELAXATION_ENABLED) 56 return; 57 58 stub_file = lang_add_input_file ("linker stubs", 59 lang_input_file_is_fake_enum, 60 NULL); 61 stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd); 62 if (stub_file->the_bfd == NULL 63 || ! bfd_set_arch_mach (stub_file->the_bfd, 64 bfd_get_arch (link_info.output_bfd), 65 bfd_get_mach (link_info.output_bfd))) 66 { 67 einfo ("%X%P: can not create BFD %E\n"); 68 return; 69 } 70 71 stub_file->the_bfd->flags |= BFD_LINKER_CREATED; 72 ldlang_add_file (stub_file); 73 } 74 75 76 struct hook_stub_info 77 { 78 lang_statement_list_type add; 79 asection *input_section; 80 }; 81 82 /* Traverse the linker tree to find the spot where the stub goes. */ 83 84 static bfd_boolean 85 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp, 86 bfd_boolean afterp) 87 { 88 lang_statement_union_type *l; 89 bfd_boolean ret; 90 91 for (; (l = *lp) != NULL; lp = &l->header.next) 92 { 93 switch (l->header.type) 94 { 95 case lang_constructors_statement_enum: 96 ret = hook_in_stub (info, &constructor_list.head, afterp); 97 if (ret) 98 return ret; 99 break; 100 101 case lang_output_section_statement_enum: 102 ret = hook_in_stub (info, 103 &l->output_section_statement.children.head, 104 afterp); 105 if (ret) 106 return ret; 107 break; 108 109 case lang_wild_statement_enum: 110 ret = hook_in_stub (info, &l->wild_statement.children.head, afterp); 111 if (ret) 112 return ret; 113 break; 114 115 case lang_group_statement_enum: 116 ret = hook_in_stub (info, &l->group_statement.children.head, afterp); 117 if (ret) 118 return ret; 119 break; 120 121 case lang_input_section_enum: 122 if (l->input_section.section == info->input_section) 123 { 124 /* We've found our section. Insert the stub immediately 125 before or after its associated input section. */ 126 if (afterp) 127 { 128 *(info->add.tail) = l->header.next; 129 l->header.next = info->add.head; 130 } 131 else 132 { 133 *lp = info->add.head; 134 *(info->add.tail) = l; 135 } 136 return TRUE; 137 } 138 break; 139 140 case lang_data_statement_enum: 141 case lang_reloc_statement_enum: 142 case lang_object_symbols_statement_enum: 143 case lang_output_statement_enum: 144 case lang_target_statement_enum: 145 case lang_input_statement_enum: 146 case lang_assignment_statement_enum: 147 case lang_padding_statement_enum: 148 case lang_address_statement_enum: 149 case lang_fill_statement_enum: 150 break; 151 152 default: 153 FAIL (); 154 break; 155 } 156 } 157 return FALSE; 158 } 159 160 /* Call-back for elf32_nios2_size_stubs. */ 161 162 /* Create a new stub section, and arrange for it to be linked 163 immediately before or after INPUT_SECTION, according to AFTERP. */ 164 165 static asection * 166 nios2elf_add_stub_section (const char *stub_sec_name, asection *input_section, 167 bfd_boolean afterp) 168 { 169 asection *stub_sec; 170 flagword flags; 171 asection *output_section; 172 const char *secname; 173 lang_output_section_statement_type *os; 174 struct hook_stub_info info; 175 176 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE 177 | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP); 178 stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd, 179 stub_sec_name, flags); 180 if (stub_sec == NULL) 181 goto err_ret; 182 183 output_section = input_section->output_section; 184 secname = bfd_get_section_name (output_section->owner, output_section); 185 os = lang_output_section_find (secname); 186 187 info.input_section = input_section; 188 lang_list_init (&info.add); 189 lang_add_section (&info.add, stub_sec, NULL, os); 190 191 if (info.add.head == NULL) 192 goto err_ret; 193 194 if (hook_in_stub (&info, &os->children.head, afterp)) 195 return stub_sec; 196 197 err_ret: 198 einfo ("%X%P: can not make stub section: %E\n"); 199 return NULL; 200 } 201 202 203 /* Another call-back for elf32_nios2_size_stubs. */ 204 205 static void 206 nios2elf_layout_sections_again (void) 207 { 208 /* If we have changed sizes of the stub sections, then we need 209 to recalculate all the section offsets. This may mean we need to 210 add even more stubs. */ 211 gld${EMULATION_NAME}_map_segments (TRUE); 212 need_laying_out = -1; 213 } 214 215 216 static void 217 build_section_lists (lang_statement_union_type *statement) 218 { 219 if (statement->header.type == lang_input_section_enum) 220 { 221 asection *i = statement->input_section.section; 222 223 if (i->sec_info_type != SEC_INFO_TYPE_JUST_SYMS 224 && (i->flags & SEC_EXCLUDE) == 0 225 && i->output_section != NULL 226 && i->output_section->owner == link_info.output_bfd) 227 { 228 nios2_elf32_next_input_section (&link_info, i); 229 } 230 } 231 } 232 233 234 /* For Nios II we use this opportunity to build linker stubs. */ 235 236 static void 237 gld${EMULATION_NAME}_after_allocation (void) 238 { 239 int ret; 240 241 /* bfd_elf_discard_info just plays with data and debugging sections, 242 ie. doesn't affect code size, so we can delay resizing the 243 sections. It's likely we'll resize everything in the process of 244 adding stubs. */ 245 ret = bfd_elf_discard_info (link_info.output_bfd, &link_info); 246 if (ret < 0) 247 { 248 einfo ("%X%P: .eh_frame/.stab edit: %E\n"); 249 return; 250 } 251 else if (ret > 0) 252 need_laying_out = 1; 253 254 /* If generating a relocatable output file, then we don't 255 have to examine the relocs. */ 256 if (stub_file != NULL && !link_info.relocatable && RELAXATION_ENABLED) 257 { 258 ret = nios2_elf32_setup_section_lists (link_info.output_bfd, &link_info); 259 if (ret != 0) 260 { 261 if (ret < 0) 262 { 263 einfo ("%X%P: can not size stub section: %E\n"); 264 return; 265 } 266 267 lang_for_each_statement (build_section_lists); 268 269 /* Call into the BFD backend to do the real work. */ 270 if (! nios2_elf32_size_stubs (link_info.output_bfd, 271 stub_file->the_bfd, 272 &link_info, 273 &nios2elf_add_stub_section, 274 &nios2elf_layout_sections_again)) 275 { 276 einfo ("%X%P: can not size stub section: %E\n"); 277 return; 278 } 279 } 280 } 281 282 if (need_laying_out != -1) 283 gld${EMULATION_NAME}_map_segments (need_laying_out); 284 285 if (!link_info.relocatable && RELAXATION_ENABLED) 286 { 287 /* Now build the linker stubs. */ 288 if (stub_file != NULL && stub_file->the_bfd->sections != NULL) 289 { 290 if (! nios2_elf32_build_stubs (&link_info)) 291 einfo ("%X%P: can not build stubs: %E\n"); 292 } 293 } 294 } 295 296 297 /* Avoid processing the fake stub_file in vercheck, stat_needed and 298 check_needed routines. */ 299 300 static void (*real_func) (lang_input_statement_type *); 301 302 static void nios2_for_each_input_file_wrapper (lang_input_statement_type *l) 303 { 304 if (l != stub_file) 305 (*real_func) (l); 306 } 307 308 static void 309 nios2_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) 310 { 311 real_func = func; 312 lang_for_each_input_file (&nios2_for_each_input_file_wrapper); 313 } 314 315 #define lang_for_each_input_file nios2_lang_for_each_input_file 316 317 EOF 318 319 320 # Put these extra nios2elf routines in ld_${EMULATION_NAME}_emulation 321 # 322 LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation 323 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=nios2elf_create_output_section_statements 324
