1# This shell script emits a C file. -*- C -*- 2# Copyright 2004, 2006, 2007, 2008 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 21fragment <<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. */ 33static lang_input_statement_type *stub_file; 34static bfd *stub_bfd; 35 36static void 37mips_after_parse (void) 38{ 39 /* .gnu.hash and the MIPS ABI require .dynsym to be sorted in different 40 ways. .gnu.hash needs symbols to be grouped by hash code whereas the 41 MIPS ABI requires a mapping between the GOT and the symbol table. */ 42 if (link_info.emit_gnu_hash) 43 { 44 einfo ("%X%P: .gnu.hash is incompatible with the MIPS ABI\n"); 45 link_info.emit_hash = TRUE; 46 link_info.emit_gnu_hash = FALSE; 47 } 48 after_parse_default (); 49} 50 51struct hook_stub_info 52{ 53 lang_statement_list_type add; 54 asection *input_section; 55}; 56 57/* Traverse the linker tree to find the spot where the stub goes. */ 58 59static bfd_boolean 60hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp) 61{ 62 lang_statement_union_type *l; 63 bfd_boolean ret; 64 65 for (; (l = *lp) != NULL; lp = &l->header.next) 66 { 67 switch (l->header.type) 68 { 69 case lang_constructors_statement_enum: 70 ret = hook_in_stub (info, &constructor_list.head); 71 if (ret) 72 return ret; 73 break; 74 75 case lang_output_section_statement_enum: 76 ret = hook_in_stub (info, 77 &l->output_section_statement.children.head); 78 if (ret) 79 return ret; 80 break; 81 82 case lang_wild_statement_enum: 83 ret = hook_in_stub (info, &l->wild_statement.children.head); 84 if (ret) 85 return ret; 86 break; 87 88 case lang_group_statement_enum: 89 ret = hook_in_stub (info, &l->group_statement.children.head); 90 if (ret) 91 return ret; 92 break; 93 94 case lang_input_section_enum: 95 if (info->input_section == NULL 96 || l->input_section.section == info->input_section) 97 { 98 /* We've found our section. Insert the stub immediately 99 before its associated input section. */ 100 *lp = info->add.head; 101 *(info->add.tail) = l; 102 return TRUE; 103 } 104 break; 105 106 case lang_data_statement_enum: 107 case lang_reloc_statement_enum: 108 case lang_object_symbols_statement_enum: 109 case lang_output_statement_enum: 110 case lang_target_statement_enum: 111 case lang_input_statement_enum: 112 case lang_assignment_statement_enum: 113 case lang_padding_statement_enum: 114 case lang_address_statement_enum: 115 case lang_fill_statement_enum: 116 break; 117 118 default: 119 FAIL (); 120 break; 121 } 122 } 123 return FALSE; 124} 125 126/* Create a new stub section called STUB_SEC_NAME and arrange for it to 127 be linked in OUTPUT_SECTION. The section should go at the beginning of 128 OUTPUT_SECTION if INPUT_SECTION is null, otherwise it must go immediately 129 before INPUT_SECTION. */ 130 131static asection * 132mips_add_stub_section (const char *stub_sec_name, asection *input_section, 133 asection *output_section) 134{ 135 asection *stub_sec; 136 flagword flags; 137 const char *secname; 138 lang_output_section_statement_type *os; 139 struct hook_stub_info info; 140 141 /* PR 12845: If the input section has been garbage collected it will 142 not have its output section set to *ABS*. */ 143 if (bfd_is_abs_section (output_section)) 144 return NULL; 145 146 /* Create the stub file, if we haven't already. */ 147 if (stub_file == NULL) 148 { 149 stub_file = lang_add_input_file ("linker stubs", 150 lang_input_file_is_fake_enum, 151 NULL); 152 stub_bfd = bfd_create ("linker stubs", link_info.output_bfd); 153 if (stub_bfd == NULL 154 || !bfd_set_arch_mach (stub_bfd, 155 bfd_get_arch (link_info.output_bfd), 156 bfd_get_mach (link_info.output_bfd))) 157 { 158 einfo ("%F%P: can not create BFD %E\n"); 159 return NULL; 160 } 161 stub_bfd->flags |= BFD_LINKER_CREATED; 162 stub_file->the_bfd = stub_bfd; 163 ldlang_add_file (stub_file); 164 } 165 166 /* Create the section. */ 167 stub_sec = bfd_make_section_anyway (stub_bfd, stub_sec_name); 168 if (stub_sec == NULL) 169 goto err_ret; 170 171 /* Set the flags. */ 172 flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE 173 | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_KEEP); 174 if (!bfd_set_section_flags (stub_bfd, stub_sec, flags)) 175 goto err_ret; 176 177 /* Create an output section statement. */ 178 secname = bfd_get_section_name (output_section->owner, output_section); 179 os = lang_output_section_find (secname); 180 181 /* Initialize a statement list that contains only the new statement. */ 182 lang_list_init (&info.add); 183 lang_add_section (&info.add, stub_sec, NULL, os); 184 if (info.add.head == NULL) 185 goto err_ret; 186 187 /* Insert the new statement in the appropriate place. */ 188 info.input_section = input_section; 189 if (hook_in_stub (&info, &os->children.head)) 190 return stub_sec; 191 192 err_ret: 193 einfo ("%X%P: can not make stub section: %E\n"); 194 return NULL; 195} 196 197/* This is called before the input files are opened. */ 198 199static void 200mips_create_output_section_statements (void) 201{ 202 if (is_mips_elf (link_info.output_bfd)) 203 _bfd_mips_elf_init_stubs (&link_info, mips_add_stub_section); 204} 205 206/* This is called after we have merged the private data of the input bfds. */ 207 208static void 209mips_before_allocation (void) 210{ 211 flagword flags; 212 213 flags = elf_elfheader (link_info.output_bfd)->e_flags; 214 if (!link_info.shared 215 && !link_info.nocopyreloc 216 && (flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) == EF_MIPS_CPIC) 217 _bfd_mips_elf_use_plts_and_copy_relocs (&link_info); 218 219 gld${EMULATION_NAME}_before_allocation (); 220} 221 222/* Avoid processing the fake stub_file in vercheck, stat_needed and 223 check_needed routines. */ 224 225static void (*real_func) (lang_input_statement_type *); 226 227static void mips_for_each_input_file_wrapper (lang_input_statement_type *l) 228{ 229 if (l != stub_file) 230 (*real_func) (l); 231} 232 233static void 234mips_lang_for_each_input_file (void (*func) (lang_input_statement_type *)) 235{ 236 real_func = func; 237 lang_for_each_input_file (&mips_for_each_input_file_wrapper); 238} 239 240#define lang_for_each_input_file mips_lang_for_each_input_file 241 242EOF 243 244LDEMUL_AFTER_PARSE=mips_after_parse 245LDEMUL_BEFORE_ALLOCATION=mips_before_allocation 246LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=mips_create_output_section_statements 247