1 # This shell script emits a C file. -*- C -*- 2 # Copyright (C) 2004-2016 Free Software Foundation, Inc. 3 # 4 # This file is part of the 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 fragment <<EOF 22 23 #include "ldctor.h" 24 #include "elf/mips.h" 25 #include "elfxx-mips.h" 26 27 #define is_mips_elf(bfd) \ 28 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ 29 && elf_tdata (bfd) != NULL \ 30 && elf_object_id (bfd) == MIPS_ELF_DATA) 31 32 /* Fake input file for stubs. */ 33 static lang_input_statement_type *stub_file; 34 static bfd *stub_bfd; 35 36 static bfd_boolean insn32; 37 38 static void 39 mips_after_parse (void) 40 { 41 /* .gnu.hash and the MIPS ABI require .dynsym to be sorted in different 42 ways. .gnu.hash needs symbols to be grouped by hash code whereas the 43 MIPS ABI requires a mapping between the GOT and the symbol table. */ 44 if (link_info.emit_gnu_hash) 45 { 46 einfo ("%X%P: .gnu.hash is incompatible with the MIPS ABI\n"); 47 link_info.emit_hash = TRUE; 48 link_info.emit_gnu_hash = FALSE; 49 } 50 gld${EMULATION_NAME}_after_parse (); 51 } 52 53 struct hook_stub_info 54 { 55 lang_statement_list_type add; 56 asection *input_section; 57 }; 58 59 /* Traverse the linker tree to find the spot where the stub goes. */ 60 61 static bfd_boolean 62 hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) 63 { 64 lang_statement_union_type *l; 65 bfd_boolean ret; 66 67 for (; (l = *lp) != NULL; lp = &l->header.next) 68 { 69 switch (l->header.type) 70 { 71 case lang_constructors_statement_enum: 72 ret = hook_in_stub (info, &constructor_list.head); 73 if (ret) 74 return ret; 75 break; 76 77 case lang_output_section_statement_enum: 78 ret = hook_in_stub (info, 79 &l->output_section_statement.children.head); 80 if (ret) 81 return ret; 82 break; 83 84 case lang_wild_statement_enum: 85 ret = hook_in_stub (info, &l->wild_statement.children.head); 86 if (ret) 87 return ret; 88 break; 89 90 case lang_group_statement_enum: 91 ret = hook_in_stub (info, &l->group_statement.children.head); 92 if (ret) 93 return ret; 94 break; 95 96 case lang_input_section_enum: 97 if (info->input_section == NULL 98 || l->input_section.section == info->input_section) 99 { 100 /* We've found our section. Insert the stub immediately 101 before its associated input section. */ 102 *lp = info->add.head; 103 *(info->add.tail) = l; 104 return TRUE; 105 } 106 break; 107 108 case lang_data_statement_enum: 109 case lang_reloc_statement_enum: 110 case lang_object_symbols_statement_enum: 111 case lang_output_statement_enum: 112 case lang_target_statement_enum: 113 case lang_input_statement_enum: 114 case lang_assignment_statement_enum: 115 case lang_padding_statement_enum: 116 case lang_address_statement_enum: 117 case lang_fill_statement_enum: 118 break; 119 120 default: 121 FAIL (); 122 break; 123 } 124 } 125 return FALSE; 126 } 127 128 /* Create a new stub section called STUB_SEC_NAME and arrange for it to 129 be linked in OUTPUT_SECTION. The section should go at the beginning of 130 OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately 131 before INPUT_SECTION. */ 132 133 static asection * 134 mips_add_stub_section (const char *stub_sec_name, asection *input_section, 135 asection *output_section) 136 { 137 asection *stub_sec; 138 flagword flags; 139 lang_output_section_statement_type *os; 140 struct hook_stub_info info; 141 142 /* PR 12845: If the input section has been garbage collected it will 143 not have its output section set to *ABS*. */ 144 if (bfd_is_abs_section (output_section)) 145 return NULL; 146 147 /* Create the stub file, if we haven't already. */ 148 if (stub_file == NULL) 149 { 150 stub_file = lang_add_input_file ("linker stubs", 151 lang_input_file_is_fake_enum, 152 NULL); 153 stub_bfd = bfd_create ("linker stubs", link_info.output_bfd); 154 if (stub_bfd == NULL 155 || !bfd_set_arch_mach (stub_bfd, 156 bfd_get_arch (link_info.output_bfd), 157 bfd_get_mach (link_info.output_bfd))) 158 { 159 einfo ("%F%P: can not create BFD %E\n"); 160 return NULL; 161 } 162 stub_bfd->flags |= BFD_LINKER_CREATED; 163 stub_file->the_bfd = stub_bfd; 164 ldlang_add_file (stub_file); 165 } 166 167 /* Create the section. */ 168 stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name); 169 if (stub_sec == NULL) 170 goto err_ret; 171 172 /* Set the flags. */ 173 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE 174 | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP); 175 if (!bfd_set_section_flags (stub_bfd, stub_sec, flags)) 176 goto err_ret; 177 178 os = lang_output_section_get (output_section); 179 180 /* Initialize a statement list that contains only the new statement. */ 181 lang_list_init (&info.add); 182 lang_add_section (&info.add, stub_sec, NULL, os); 183 if (info.add.head == NULL) 184 goto err_ret; 185 186 /* Insert the new statement in the appropriate place. */ 187 info.input_section = input_section; 188 if (hook_in_stub (&info, &os->children.head)) 189 return stub_sec; 190 191 err_ret: 192 einfo ("%X%P: can not make stub section: %E\n"); 193 return NULL; 194 } 195 196 /* This is called before the input files are opened. */ 197 198 static void 199 mips_create_output_section_statements (void) 200 { 201 struct elf_link_hash_table *htab; 202 203 htab = elf_hash_table (&link_info); 204 if (is_elf_hash_table (htab) && is_mips_elf (link_info.output_bfd)) 205 _bfd_mips_elf_insn32 (&link_info, insn32); 206 207 if (is_mips_elf (link_info.output_bfd)) 208 _bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section); 209 } 210 211 /* This is called after we have merged the private data of the input bfds. */ 212 213 static void 214 mips_before_allocation (void) 215 { 216 flagword flags; 217 218 flags = elf_elfheader (link_info.output_bfd)->e_flags; 219 if (!bfd_link_pic (&link_info) 220 && !link_info.nocopyreloc 221 && (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC) 222 _bfd_mips_elf_use_plts_and_copy_relocs (&link_info); 223 224 gld${EMULATION_NAME}_before_allocation (); 225 } 226 227 /* Avoid processing the fake stub_file in vercheck, stat_needed and 228 check_needed routines. */ 229 230 static void (*real_func) (lang_input_statement_type *); 231 232 static void mips_for_each_input_file_wrapper (lang_input_statement_type *l) 233 { 234 if (l != stub_file) 235 (*real_func) (l); 236 } 237 238 static void 239 mips_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) 240 { 241 real_func = func; 242 lang_for_each_input_file (&mips_for_each_input_file_wrapper); 243 } 244 245 #define lang_for_each_input_file mips_lang_for_each_input_file 246 247 EOF 248 249 # Define some shell vars to insert bits of code into the standard elf 250 # parse_args and list_options functions. 251 # 252 PARSE_AND_LIST_PROLOGUE=' 253 enum 254 { 255 OPTION_INSN32 = 301, 256 OPTION_NO_INSN32 257 }; 258 ' 259 260 PARSE_AND_LIST_LONGOPTS=' 261 { "insn32", no_argument, NULL, OPTION_INSN32 }, 262 { "no-insn32", no_argument, NULL, OPTION_NO_INSN32 }, 263 ' 264 265 PARSE_AND_LIST_OPTIONS=' 266 fprintf (file, _("\ 267 --insn32 Only generate 32-bit microMIPS instructions\n" 268 )); 269 fprintf (file, _("\ 270 --no-insn32 Generate all microMIPS instructions\n" 271 )); 272 ' 273 274 PARSE_AND_LIST_ARGS_CASES=' 275 case OPTION_INSN32: 276 insn32 = TRUE; 277 break; 278 279 case OPTION_NO_INSN32: 280 insn32 = FALSE; 281 break; 282 ' 283 284 LDEMUL_AFTER_PARSE=mips_after_parse 285 LDEMUL_BEFORE_ALLOCATION=mips_before_allocation 286 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements 287
