1# This shell script emits a C file. -*- C -*- 2# Copyright 2000, 2001, 2003, 2007, 2008 Free Software Foundation, Inc. 3# Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em 4# 5# This file is part of the GNU Binutils. 6# 7# This program is free software; you can redistribute it and/or modify 8# it under the terms of the GNU General Public License as published by 9# the Free Software Foundation; either version 3 of the License, or 10# (at your option) any later version. 11# 12# This program is distributed in the hope that it will be useful, 13# but WITHOUT ANY WARRANTY; without even the implied warranty of 14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15# GNU General Public License for more details. 16# 17# You should have received a copy of the GNU General Public License 18# along with this program; if not, write to the Free Software 19# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20# MA 02110-1301, USA. 21 22 23# This file is sourced from elf32.em, and defines some extra routines for m68k 24# embedded systems using ELF and for some other systems using m68k ELF. While 25# it is sourced from elf32.em for all m68k ELF configurations, here we include 26# only the features we want depending on the configuration. 27 28case ${target} in 29 m68*-*-elf) 30 echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c 31 ;; 32esac 33 34case ${target} in 35 *-linux*) 36# Don't use multi-GOT by default due to glibc linker's assumption 37# that GOT pointer points to GOT[0]. 38# got_handling_target_default=GOT_HANDLING_MULTIGOT 39 got_handling_target_default=GOT_HANDLING_SINGLE 40 ;; 41 *) 42 got_handling_target_default=GOT_HANDLING_SINGLE 43 ;; 44esac 45 46fragment <<EOF 47 48#define GOT_HANDLING_SINGLE (0) 49#define GOT_HANDLING_NEGATIVE (1) 50#define GOT_HANDLING_MULTIGOT (2) 51#define GOT_HANDLING_TARGET_DEFAULT ${got_handling_target_default} 52 53/* How to generate GOT. */ 54static int got_handling = GOT_HANDLING_DEFAULT; 55 56#ifdef SUPPORT_EMBEDDED_RELOCS 57static void check_sections (bfd *, asection *, void *); 58#endif 59 60/* This function is run after all the input files have been opened. */ 61 62static void 63m68k_elf_after_open (void) 64{ 65 /* Call the standard elf routine. */ 66 gld${EMULATION_NAME}_after_open (); 67 68#ifdef SUPPORT_EMBEDDED_RELOCS 69 if (command_line.embedded_relocs 70 && (! link_info.relocatable)) 71 { 72 bfd *abfd; 73 74 /* In the embedded relocs mode we create a .emreloc section for each 75 input file with a nonzero .data section. The BFD backend will fill in 76 these sections with magic numbers which can be used to relocate the 77 data section at run time. */ 78 for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next) 79 { 80 asection *datasec; 81 82 /* As first-order business, make sure that each input BFD is either 83 COFF or ELF. We need to call a special BFD backend function to 84 generate the embedded relocs, and we have such functions only for 85 COFF and ELF. */ 86 if (bfd_get_flavour (abfd) != bfd_target_coff_flavour 87 && bfd_get_flavour (abfd) != bfd_target_elf_flavour) 88 einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n"); 89 90 datasec = bfd_get_section_by_name (abfd, ".data"); 91 92 /* Note that we assume that the reloc_count field has already 93 been set up. We could call bfd_get_reloc_upper_bound, but 94 that returns the size of a memory buffer rather than a reloc 95 count. We do not want to call bfd_canonicalize_reloc, 96 because although it would always work it would force us to 97 read in the relocs into BFD canonical form, which would waste 98 a significant amount of time and memory. */ 99 if (datasec != NULL && datasec->reloc_count > 0) 100 { 101 asection *relsec; 102 103 relsec = bfd_make_section_with_flags (abfd, ".emreloc", 104 (SEC_ALLOC 105 | SEC_LOAD 106 | SEC_HAS_CONTENTS 107 | SEC_IN_MEMORY)); 108 if (relsec == NULL 109 || ! bfd_set_section_alignment (abfd, relsec, 2) 110 || ! bfd_set_section_size (abfd, relsec, 111 datasec->reloc_count * 12)) 112 einfo ("%F%B: can not create .emreloc section: %E\n"); 113 } 114 115 /* Double check that all other data sections are empty, as is 116 required for embedded PIC code. */ 117 bfd_map_over_sections (abfd, check_sections, datasec); 118 } 119 } 120#endif /* SUPPORT_EMBEDDED_RELOCS */ 121} 122 123#ifdef SUPPORT_EMBEDDED_RELOCS 124/* Check that of the data sections, only the .data section has 125 relocs. This is called via bfd_map_over_sections. */ 126 127static void 128check_sections (bfd *abfd, asection *sec, void *datasec) 129{ 130 if ((bfd_get_section_flags (abfd, sec) & SEC_DATA) 131 && sec != datasec 132 && sec->reloc_count != 0) 133 einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n", 134 abfd, bfd_get_section_name (abfd, sec)); 135} 136 137#endif /* SUPPORT_EMBEDDED_RELOCS */ 138 139/* This function is called after the section sizes and offsets have 140 been set. */ 141 142static void 143m68k_elf_after_allocation (void) 144{ 145 /* Call the standard elf routine. */ 146 after_allocation_default (); 147 148#ifdef SUPPORT_EMBEDDED_RELOCS 149 if (command_line.embedded_relocs 150 && (! link_info.relocatable)) 151 { 152 bfd *abfd; 153 154 /* If we are generating embedded relocs, call a special BFD backend 155 routine to do the work. */ 156 for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next) 157 { 158 asection *datasec, *relsec; 159 char *errmsg; 160 161 datasec = bfd_get_section_by_name (abfd, ".data"); 162 163 if (datasec == NULL || datasec->reloc_count == 0) 164 continue; 165 166 relsec = bfd_get_section_by_name (abfd, ".emreloc"); 167 ASSERT (relsec != NULL); 168 169 if (bfd_get_flavour (abfd) == bfd_target_coff_flavour) 170 { 171 if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info, 172 datasec, relsec, 173 &errmsg)) 174 { 175 if (errmsg == NULL) 176 einfo ("%B%X: can not create runtime reloc information: %E\n", 177 abfd); 178 else 179 einfo ("%X%B: can not create runtime reloc information: %s\n", 180 abfd, errmsg); 181 } 182 } 183 else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) 184 { 185 if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info, 186 datasec, relsec, 187 &errmsg)) 188 { 189 if (errmsg == NULL) 190 einfo ("%B%X: can not create runtime reloc information: %E\n", 191 abfd); 192 else 193 einfo ("%X%B: can not create runtime reloc information: %s\n", 194 abfd, errmsg); 195 } 196 } 197 else 198 abort (); 199 } 200 } 201#endif /* SUPPORT_EMBEDDED_RELOCS */ 202} 203 204/* This is a convenient point to tell BFD about target specific flags. 205 After the output has been created, but before inputs are read. */ 206 207static void 208elf_m68k_create_output_section_statements (void) 209{ 210 bfd_elf_m68k_set_target_options (&link_info, got_handling); 211} 212 213EOF 214 215# Define some shell vars to insert bits of code into the standard elf 216# parse_args and list_options functions. 217# 218PARSE_AND_LIST_PROLOGUE=' 219#define OPTION_GOT 301 220' 221 222PARSE_AND_LIST_LONGOPTS=' 223 { "got", required_argument, NULL, OPTION_GOT}, 224' 225 226PARSE_AND_LIST_OPTIONS=' 227 fprintf (file, _(" --got=<type> Specify GOT handling scheme\n")); 228' 229 230PARSE_AND_LIST_ARGS_CASES=' 231 case OPTION_GOT: 232 if (strcmp (optarg, "target") == 0) 233 got_handling = GOT_HANDLING_TARGET_DEFAULT; 234 else if (strcmp (optarg, "single") == 0) 235 got_handling = 0; 236 else if (strcmp (optarg, "negative") == 0) 237 got_handling = 1; 238 else if (strcmp (optarg, "multigot") == 0) 239 got_handling = 2; 240 else 241 einfo (_("Unrecognized --got argument '\''%s'\''.\n"), optarg); 242 break; 243' 244 245# We have our own after_open and after_allocation functions, but they call 246# the standard routines, so give them a different name. 247LDEMUL_AFTER_OPEN=m68k_elf_after_open 248LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation 249LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=elf_m68k_create_output_section_statements 250