ld/emultempl/ppc32elf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2003, 2005, 2007, 2008, 2009, 2010, 2011, 2012
   3 #   Free Software Foundation, Inc.
   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 extra powerpc32-elf
  24 # specific routines.
  25 #
  26 fragment <<EOF
  27
  28 #include "libbfd.h"
  29 #include "elf32-ppc.h"
  30 #include "ldlex.h"
  31
  32 #define is_ppc_elf(bfd) \
  33   (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
  34    && elf_object_id (bfd) == PPC32_ELF_DATA)
  35
  36 /* Whether to run tls optimization.  */
  37 static int notlsopt = 0;
  38
  39 /* Choose the correct place for .got.  */
  40 static int old_got = 0;
  41
  42 static struct ppc_elf_params params = { PLT_UNSET, -1, 0, 0, 0, 0 };
  43
  44 static void
  45 ppc_after_open_output (void)
  46 {
  47   if (params.emit_stub_syms < 0)
  48     params.emit_stub_syms = link_info.emitrelocations || link_info.shared;
  49   if (params.pagesize == 0)
  50     params.pagesize = config.commonpagesize;
  51   if (link_info.relocatable)
  52     params.ppc476_workaround = 0;
  53   ppc_elf_link_params (&link_info, &params);
  54 }
  55
  56 static void
  57 ppc_after_open (void)
  58 {
  59   if (is_ppc_elf (link_info.output_bfd))
  60     {
  61       int new_plt;
  62       int keep_new;
  63       unsigned int num_plt;
  64       unsigned int num_got;
  65       lang_output_section_statement_type *os;
  66       lang_output_section_statement_type *plt_os[2];
  67       lang_output_section_statement_type *got_os[2];
  68
  69       new_plt = ppc_elf_select_plt_layout (link_info.output_bfd, &link_info);
  70       if (new_plt < 0)
  71         einfo ("%X%P: select_plt_layout problem %E\n");
  72
  73       num_got = 0;
  74       num_plt = 0;
  75       for (os = &lang_output_section_statement.head->output_section_statement;
  76            os != NULL;
  77            os = os->next)
  78         {
  79           if (os->constraint == SPECIAL && strcmp (os->name, ".plt") == 0)
  80             {
  81               if (num_plt < 2)
  82                 plt_os[num_plt] = os;
  83               ++num_plt;
  84             }
  85           if (os->constraint == SPECIAL && strcmp (os->name, ".got") == 0)
  86             {
  87               if (num_got < 2)
  88                 got_os[num_got] = os;
  89               ++num_got;
  90             }
  91         }
  92
  93       keep_new = new_plt == 1 ? 0 : -1;
  94       if (num_plt == 2)
  95         {
  96           plt_os[0]->constraint = keep_new;
  97           plt_os[1]->constraint = ~keep_new;
  98         }
  99       if (num_got == 2)
 100         {
 101           if (old_got)
 102             keep_new = -1;
 103           got_os[0]->constraint = keep_new;
 104           got_os[1]->constraint = ~keep_new;
 105         }
 106     }
 107
 108   gld${EMULATION_NAME}_after_open ();
 109 }
 110
 111 static void
 112 ppc_before_allocation (void)
 113 {
 114   if (is_ppc_elf (link_info.output_bfd))
 115     {
 116       if (ppc_elf_tls_setup (link_info.output_bfd, &link_info)
 117           && !notlsopt)
 118         {
 119           if (!ppc_elf_tls_optimize (link_info.output_bfd, &link_info))
 120             {
 121               einfo ("%X%P: TLS problem %E\n");
 122               return;
 123             }
 124         }
 125     }
 126
 127   gld${EMULATION_NAME}_before_allocation ();
 128
 129   if (RELAXATION_ENABLED)
 130     params.branch_trampolines = 1;
 131
 132   /* Turn on relaxation if executable sections have addresses that
 133      might make branches overflow.  */
 134   else if (!RELAXATION_DISABLED_BY_USER)
 135     {
 136       bfd_vma low = (bfd_vma) -1;
 137       bfd_vma high = 0;
 138       asection *o;
 139
 140       /* Run lang_size_sections (if not already done).  */
 141       if (expld.phase != lang_mark_phase_enum)
 142         {
 143           expld.phase = lang_mark_phase_enum;
 144           expld.dataseg.phase = exp_dataseg_none;
 145           one_lang_size_sections_pass (NULL, FALSE);
 146           lang_reset_memory_regions ();
 147         }
 148
 149       for (o = link_info.output_bfd->sections; o != NULL; o = o->next)
 150         {
 151           if ((o->flags & (SEC_ALLOC | SEC_CODE)) != (SEC_ALLOC | SEC_CODE))
 152             continue;
 153           if (o->rawsize == 0)
 154             continue;
 155           if (low > o->vma)
 156             low = o->vma;
 157           if (high < o->vma + o->rawsize - 1)
 158             high = o->vma + o->rawsize - 1;
 159         }
 160       if (high > low && high - low > (1 << 25) - 1)
 161         params.branch_trampolines = 1;
 162     }
 163
 164   if (params.ppc476_workaround || params.branch_trampolines)
 165     ENABLE_RELAXATION;
 166 }
 167
 168 EOF
 169
 170 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
 171   fragment <<EOF
 172 /* Special handling for embedded SPU executables.  */
 173 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
 174 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
 175
 176 static bfd_boolean
 177 ppc_recognized_file (lang_input_statement_type *entry)
 178 {
 179   if (embedded_spu_file (entry, "-m32"))
 180     return TRUE;
 181
 182   return gld${EMULATION_NAME}_load_symbols (entry);
 183 }
 184
 185 EOF
 186 LDEMUL_RECOGNIZED_FILE=ppc_recognized_file
 187 fi
 188
 189 # Define some shell vars to insert bits of code into the standard elf
 190 # parse_args and list_options functions.
 191 #
 192 PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}'
 193 #define OPTION_NO_TLS_OPT               321
 194 #define OPTION_NO_TLS_GET_ADDR_OPT      (OPTION_NO_TLS_OPT + 1)
 195 #define OPTION_NEW_PLT                  (OPTION_NO_TLS_GET_ADDR_OPT + 1)
 196 #define OPTION_OLD_PLT                  (OPTION_NEW_PLT + 1)
 197 #define OPTION_OLD_GOT                  (OPTION_OLD_PLT + 1)
 198 #define OPTION_STUBSYMS                 (OPTION_OLD_GOT + 1)
 199 #define OPTION_NO_STUBSYMS              (OPTION_STUBSYMS + 1)
 200 #define OPTION_PPC476_WORKAROUND        (OPTION_NO_STUBSYMS + 1)
 201 #define OPTION_NO_PPC476_WORKAROUND     (OPTION_PPC476_WORKAROUND + 1)
 202 '
 203
 204 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
 205   { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
 206   { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
 207   { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
 208   { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
 209   { "secure-plt", no_argument, NULL, OPTION_NEW_PLT },
 210   { "bss-plt", no_argument, NULL, OPTION_OLD_PLT },
 211   { "sdata-got", no_argument, NULL, OPTION_OLD_GOT },
 212   { "ppc476-workaround", optional_argument, NULL, OPTION_PPC476_WORKAROUND },
 213   { "no-ppc476-workaround", no_argument, NULL, OPTION_NO_PPC476_WORKAROUND },
 214 '
 215
 216 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
 217   fprintf (file, _("\
 218   --emit-stub-syms            Label linker stubs with a symbol.\n\
 219   --no-emit-stub-syms         Don'\''t label linker stubs with a symbol.\n\
 220   --no-tls-optimize           Don'\''t try to optimize TLS accesses.\n\
 221   --no-tls-get-addr-optimize  Don'\''t use a special __tls_get_addr call.\n\
 222   --secure-plt                Use new-style PLT if possible.\n\
 223   --bss-plt                   Force old-style BSS PLT.\n\
 224   --sdata-got                 Force GOT location just before .sdata.\n\
 225   --ppc476-workaround [=pagesize]\n\
 226                               Avoid a cache bug on ppc476.\n\
 227   --no-ppc476-workaround      Disable workaround.\n"
 228                    ));
 229 '
 230
 231 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
 232     case OPTION_STUBSYMS:
 233       params.emit_stub_syms = 1;
 234       break;
 235
 236     case OPTION_NO_STUBSYMS:
 237       params.emit_stub_syms = 0;
 238       break;
 239
 240     case OPTION_NO_TLS_OPT:
 241       notlsopt = 1;
 242       break;
 243
 244     case OPTION_NO_TLS_GET_ADDR_OPT:
 245       params.no_tls_get_addr_opt = 1;
 246       break;
 247
 248     case OPTION_NEW_PLT:
 249       params.plt_style = PLT_NEW;
 250       break;
 251
 252     case OPTION_OLD_PLT:
 253       params.plt_style = PLT_OLD;
 254       break;
 255
 256     case OPTION_OLD_GOT:
 257       old_got = 1;
 258       break;
 259
 260     case OPTION_TRADITIONAL_FORMAT:
 261       notlsopt = 1;
 262       params.no_tls_get_addr_opt = 1;
 263       return FALSE;
 264
 265     case OPTION_PPC476_WORKAROUND:
 266       params.ppc476_workaround = 1;
 267       if (optarg != NULL)
 268         {
 269           char *end;
 270           params.pagesize = strtoul (optarg, &end, 0);
 271           if (*end
 272               || (params.pagesize < 4096 && params.pagesize != 0)
 273               || params.pagesize != (params.pagesize & -params.pagesize))
 274             einfo (_("%P%F: invalid pagesize `%s'\''\n"), optarg);
 275         }
 276       break;
 277
 278     case OPTION_NO_PPC476_WORKAROUND:
 279       params.ppc476_workaround = 0;
 280       break;
 281 '
 282
 283 # Put these extra ppc32elf routines in ld_${EMULATION_NAME}_emulation
 284 #
 285 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_after_open_output
 286 LDEMUL_AFTER_OPEN=ppc_after_open
 287 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation