| 1 | # This shell script emits a C file. -*- C -*- |
| 2 | # Copyright 2000, 2001, 2003, 2005, 2007, 2008, 2009 |
| 3 | # Free Software Foundation, Inc. |
| 4 | # Written by Michael Sokolov <msokolov@ivan.Harhan.ORG>, based on armelf.em |
| 5 | # |
| 6 | # This file is part of the GNU Binutils. |
| 7 | # |
| 8 | # This program is free software; you can redistribute it and/or modify |
| 9 | # it under the terms of the GNU General Public License as published by |
| 10 | # the Free Software Foundation; either version 3 of the License, or |
| 11 | # (at your option) any later version. |
| 12 | # |
| 13 | # This program is distributed in the hope that it will be useful, |
| 14 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | # GNU General Public License for more details. |
| 17 | # |
| 18 | # You should have received a copy of the GNU General Public License |
| 19 | # along with this program; if not, write to the Free Software |
| 20 | # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 21 | # MA 02110-1301, USA. |
| 22 | |
| 23 | |
| 24 | # This file is sourced from elf32.em, and defines some extra routines for m68k |
| 25 | # embedded systems using ELF and for some other systems using m68k ELF. While |
| 26 | # it is sourced from elf32.em for all m68k ELF configurations, here we include |
| 27 | # only the features we want depending on the configuration. |
| 28 | |
| 29 | case ${target} in |
| 30 | m68*-*-elf) |
| 31 | echo "#define SUPPORT_EMBEDDED_RELOCS" >>e${EMULATION_NAME}.c |
| 32 | ;; |
| 33 | esac |
| 34 | |
| 35 | case ${target} in |
| 36 | *-linux*) |
| 37 | # Don't use multi-GOT by default due to glibc linker's assumption |
| 38 | # that GOT pointer points to GOT[0]. |
| 39 | # got_handling_target_default=GOT_HANDLING_MULTIGOT |
| 40 | got_handling_target_default=GOT_HANDLING_SINGLE |
| 41 | ;; |
| 42 | *) |
| 43 | got_handling_target_default=GOT_HANDLING_SINGLE |
| 44 | ;; |
| 45 | esac |
| 46 | |
| 47 | fragment <<EOF |
| 48 | |
| 49 | #define GOT_HANDLING_SINGLE (0) |
| 50 | #define GOT_HANDLING_NEGATIVE (1) |
| 51 | #define GOT_HANDLING_MULTIGOT (2) |
| 52 | #define GOT_HANDLING_TARGET_DEFAULT ${got_handling_target_default} |
| 53 | |
| 54 | /* How to generate GOT. */ |
| 55 | static int got_handling = GOT_HANDLING_DEFAULT; |
| 56 | |
| 57 | #ifdef SUPPORT_EMBEDDED_RELOCS |
| 58 | static void check_sections (bfd *, asection *, void *); |
| 59 | #endif |
| 60 | |
| 61 | /* This function is run after all the input files have been opened. */ |
| 62 | |
| 63 | static void |
| 64 | m68k_elf_after_open (void) |
| 65 | { |
| 66 | /* Call the standard elf routine. */ |
| 67 | gld${EMULATION_NAME}_after_open (); |
| 68 | |
| 69 | #ifdef SUPPORT_EMBEDDED_RELOCS |
| 70 | if (command_line.embedded_relocs |
| 71 | && (! link_info.relocatable)) |
| 72 | { |
| 73 | bfd *abfd; |
| 74 | |
| 75 | /* In the embedded relocs mode we create a .emreloc section for each |
| 76 | input file with a nonzero .data section. The BFD backend will fill in |
| 77 | these sections with magic numbers which can be used to relocate the |
| 78 | data section at run time. */ |
| 79 | for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next) |
| 80 | { |
| 81 | asection *datasec; |
| 82 | |
| 83 | /* As first-order business, make sure that each input BFD is either |
| 84 | COFF or ELF. We need to call a special BFD backend function to |
| 85 | generate the embedded relocs, and we have such functions only for |
| 86 | COFF and ELF. */ |
| 87 | if (bfd_get_flavour (abfd) != bfd_target_coff_flavour |
| 88 | && bfd_get_flavour (abfd) != bfd_target_elf_flavour) |
| 89 | einfo ("%F%B: all input objects must be COFF or ELF for --embedded-relocs\n"); |
| 90 | |
| 91 | datasec = bfd_get_section_by_name (abfd, ".data"); |
| 92 | |
| 93 | /* Note that we assume that the reloc_count field has already |
| 94 | been set up. We could call bfd_get_reloc_upper_bound, but |
| 95 | that returns the size of a memory buffer rather than a reloc |
| 96 | count. We do not want to call bfd_canonicalize_reloc, |
| 97 | because although it would always work it would force us to |
| 98 | read in the relocs into BFD canonical form, which would waste |
| 99 | a significant amount of time and memory. */ |
| 100 | if (datasec != NULL && datasec->reloc_count > 0) |
| 101 | { |
| 102 | asection *relsec; |
| 103 | |
| 104 | relsec = bfd_make_section_with_flags (abfd, ".emreloc", |
| 105 | (SEC_ALLOC |
| 106 | | SEC_LOAD |
| 107 | | SEC_HAS_CONTENTS |
| 108 | | SEC_IN_MEMORY)); |
| 109 | if (relsec == NULL |
| 110 | || ! bfd_set_section_alignment (abfd, relsec, 2) |
| 111 | || ! bfd_set_section_size (abfd, relsec, |
| 112 | datasec->reloc_count * 12)) |
| 113 | einfo ("%F%B: can not create .emreloc section: %E\n"); |
| 114 | } |
| 115 | |
| 116 | /* Double check that all other data sections are empty, as is |
| 117 | required for embedded PIC code. */ |
| 118 | bfd_map_over_sections (abfd, check_sections, datasec); |
| 119 | } |
| 120 | } |
| 121 | #endif /* SUPPORT_EMBEDDED_RELOCS */ |
| 122 | } |
| 123 | |
| 124 | #ifdef SUPPORT_EMBEDDED_RELOCS |
| 125 | /* Check that of the data sections, only the .data section has |
| 126 | relocs. This is called via bfd_map_over_sections. */ |
| 127 | |
| 128 | static void |
| 129 | check_sections (bfd *abfd, asection *sec, void *datasec) |
| 130 | { |
| 131 | if ((bfd_get_section_flags (abfd, sec) & SEC_DATA) |
| 132 | && sec != datasec |
| 133 | && sec->reloc_count != 0) |
| 134 | einfo ("%B%X: section %s has relocs; can not use --embedded-relocs\n", |
| 135 | abfd, bfd_get_section_name (abfd, sec)); |
| 136 | } |
| 137 | |
| 138 | #endif /* SUPPORT_EMBEDDED_RELOCS */ |
| 139 | |
| 140 | /* This function is called after the section sizes and offsets have |
| 141 | been set. */ |
| 142 | |
| 143 | static void |
| 144 | m68k_elf_after_allocation (void) |
| 145 | { |
| 146 | /* Call the standard elf routine. */ |
| 147 | gld${EMULATION_NAME}_after_allocation (); |
| 148 | |
| 149 | #ifdef SUPPORT_EMBEDDED_RELOCS |
| 150 | if (command_line.embedded_relocs |
| 151 | && (! link_info.relocatable)) |
| 152 | { |
| 153 | bfd *abfd; |
| 154 | |
| 155 | /* If we are generating embedded relocs, call a special BFD backend |
| 156 | routine to do the work. */ |
| 157 | for (abfd = link_info.input_bfds; abfd != NULL; abfd = abfd->link_next) |
| 158 | { |
| 159 | asection *datasec, *relsec; |
| 160 | char *errmsg; |
| 161 | |
| 162 | datasec = bfd_get_section_by_name (abfd, ".data"); |
| 163 | |
| 164 | if (datasec == NULL || datasec->reloc_count == 0) |
| 165 | continue; |
| 166 | |
| 167 | relsec = bfd_get_section_by_name (abfd, ".emreloc"); |
| 168 | ASSERT (relsec != NULL); |
| 169 | |
| 170 | if (bfd_get_flavour (abfd) == bfd_target_coff_flavour) |
| 171 | { |
| 172 | if (! bfd_m68k_coff_create_embedded_relocs (abfd, &link_info, |
| 173 | datasec, relsec, |
| 174 | &errmsg)) |
| 175 | { |
| 176 | if (errmsg == NULL) |
| 177 | einfo ("%B%X: can not create runtime reloc information: %E\n", |
| 178 | abfd); |
| 179 | else |
| 180 | einfo ("%X%B: can not create runtime reloc information: %s\n", |
| 181 | abfd, errmsg); |
| 182 | } |
| 183 | } |
| 184 | else if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) |
| 185 | { |
| 186 | if (! bfd_m68k_elf32_create_embedded_relocs (abfd, &link_info, |
| 187 | datasec, relsec, |
| 188 | &errmsg)) |
| 189 | { |
| 190 | if (errmsg == NULL) |
| 191 | einfo ("%B%X: can not create runtime reloc information: %E\n", |
| 192 | abfd); |
| 193 | else |
| 194 | einfo ("%X%B: can not create runtime reloc information: %s\n", |
| 195 | abfd, errmsg); |
| 196 | } |
| 197 | } |
| 198 | else |
| 199 | abort (); |
| 200 | } |
| 201 | } |
| 202 | #endif /* SUPPORT_EMBEDDED_RELOCS */ |
| 203 | } |
| 204 | |
| 205 | /* This is a convenient point to tell BFD about target specific flags. |
| 206 | After the output has been created, but before inputs are read. */ |
| 207 | |
| 208 | static void |
| 209 | elf_m68k_create_output_section_statements (void) |
| 210 | { |
| 211 | bfd_elf_m68k_set_target_options (&link_info, got_handling); |
| 212 | } |
| 213 | |
| 214 | EOF |
| 215 | |
| 216 | # Define some shell vars to insert bits of code into the standard elf |
| 217 | # parse_args and list_options functions. |
| 218 | # |
| 219 | PARSE_AND_LIST_PROLOGUE=' |
| 220 | #define OPTION_GOT 301 |
| 221 | ' |
| 222 | |
| 223 | PARSE_AND_LIST_LONGOPTS=' |
| 224 | { "got", required_argument, NULL, OPTION_GOT}, |
| 225 | ' |
| 226 | |
| 227 | PARSE_AND_LIST_OPTIONS=' |
| 228 | fprintf (file, _(" --got=<type> Specify GOT handling scheme\n")); |
| 229 | ' |
| 230 | |
| 231 | PARSE_AND_LIST_ARGS_CASES=' |
| 232 | case OPTION_GOT: |
| 233 | if (strcmp (optarg, "target") == 0) |
| 234 | got_handling = GOT_HANDLING_TARGET_DEFAULT; |
| 235 | else if (strcmp (optarg, "single") == 0) |
| 236 | got_handling = 0; |
| 237 | else if (strcmp (optarg, "negative") == 0) |
| 238 | got_handling = 1; |
| 239 | else if (strcmp (optarg, "multigot") == 0) |
| 240 | got_handling = 2; |
| 241 | else |
| 242 | einfo (_("Unrecognized --got argument '\''%s'\''.\n"), optarg); |
| 243 | break; |
| 244 | ' |
| 245 | |
| 246 | # We have our own after_open and after_allocation functions, but they call |
| 247 | # the standard routines, so give them a different name. |
| 248 | LDEMUL_AFTER_OPEN=m68k_elf_after_open |
| 249 | LDEMUL_AFTER_ALLOCATION=m68k_elf_after_allocation |
| 250 | LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=elf_m68k_create_output_section_statements |