ld/emultempl/ppc32elf.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2003, 2005, 2007, 2008, 2009 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
  22 # This file is sourced from elf32.em, and defines extra powerpc32-elf
  23 # specific routines.
  24 #
  25 fragment <<EOF
  26
  27 #include "libbfd.h"
  28 #include "elf32-ppc.h"
  29
  30 #define is_ppc_elf(bfd) \
  31   (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
  32    && elf_object_id (bfd) == PPC32_ELF_DATA)
  33
  34 /* Whether to run tls optimization.  */
  35 static int notlsopt = 0;
  36 static int no_tls_get_addr_opt = 0;
  37
  38 /* Whether to emit symbols for stubs.  */
  39 static int emit_stub_syms = -1;
  40
  41 /* Chooses the correct place for .plt and .got.  */
  42 static enum ppc_elf_plt_type plt_style = PLT_UNSET;
  43 static int old_got = 0;
  44
  45 static void
  46 ppc_after_open (void)
  47 {
  48   if (is_ppc_elf (link_info.output_bfd))
  49     {
  50       int new_plt;
  51       int keep_new;
  52       unsigned int num_plt;
  53       unsigned int num_got;
  54       lang_output_section_statement_type *os;
  55       lang_output_section_statement_type *plt_os[2];
  56       lang_output_section_statement_type *got_os[2];
  57
  58       if (emit_stub_syms < 0)
  59         emit_stub_syms = link_info.emitrelocations || link_info.shared;
  60       new_plt = ppc_elf_select_plt_layout (link_info.output_bfd, &link_info,
  61                                            plt_style, emit_stub_syms);
  62       if (new_plt < 0)
  63         einfo ("%X%P: select_plt_layout problem %E\n");
  64
  65       num_got = 0;
  66       num_plt = 0;
  67       for (os = &lang_output_section_statement.head->output_section_statement;
  68            os != NULL;
  69            os = os->next)
  70         {
  71           if (os->constraint == SPECIAL && strcmp (os->name, ".plt") == 0)
  72             {
  73               if (num_plt < 2)
  74                 plt_os[num_plt] = os;
  75               ++num_plt;
  76             }
  77           if (os->constraint == SPECIAL && strcmp (os->name, ".got") == 0)
  78             {
  79               if (num_got < 2)
  80                 got_os[num_got] = os;
  81               ++num_got;
  82             }
  83         }
  84
  85       keep_new = new_plt == 1 ? 0 : -1;
  86       if (num_plt == 2)
  87         {
  88           plt_os[0]->constraint = keep_new;
  89           plt_os[1]->constraint = ~keep_new;
  90         }
  91       if (num_got == 2)
  92         {
  93           if (old_got)
  94             keep_new = -1;
  95           got_os[0]->constraint = keep_new;
  96           got_os[1]->constraint = ~keep_new;
  97         }
  98     }
  99
 100   gld${EMULATION_NAME}_after_open ();
 101 }
 102
 103 static void
 104 ppc_before_allocation (void)
 105 {
 106   if (is_ppc_elf (link_info.output_bfd))
 107     {
 108       if (ppc_elf_tls_setup (link_info.output_bfd, &link_info,
 109                              no_tls_get_addr_opt)
 110           && !notlsopt)
 111         {
 112           if (!ppc_elf_tls_optimize (link_info.output_bfd, &link_info))
 113             {
 114               einfo ("%X%P: TLS problem %E\n");
 115               return;
 116             }
 117         }
 118     }
 119
 120   gld${EMULATION_NAME}_before_allocation ();
 121
 122   /* Turn on relaxation if executable sections have addresses that
 123      might make branches overflow.  */
 124   if (RELAXATION_DISABLED_BY_DEFAULT)
 125     {
 126       bfd_vma low = (bfd_vma) -1;
 127       bfd_vma high = 0;
 128       asection *o;
 129
 130       /* Run lang_size_sections (if not already done).  */
 131       if (expld.phase != lang_mark_phase_enum)
 132         {
 133           expld.phase = lang_mark_phase_enum;
 134           expld.dataseg.phase = exp_dataseg_none;
 135           one_lang_size_sections_pass (NULL, FALSE);
 136           lang_reset_memory_regions ();
 137         }
 138
 139       for (o = link_info.output_bfd->sections; o != NULL; o = o->next)
 140         {
 141           if ((o->flags & (SEC_ALLOC | SEC_CODE)) != (SEC_ALLOC | SEC_CODE))
 142             continue;
 143           if (o->rawsize == 0)
 144             continue;
 145           if (low > o->vma)
 146             low = o->vma;
 147           if (high < o->vma + o->rawsize - 1)
 148             high = o->vma + o->rawsize - 1;
 149         }
 150       if (high > low && high - low > (1 << 25) - 1)
 151         ENABLE_RELAXATION;
 152     }
 153 }
 154
 155 EOF
 156
 157 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
 158   fragment <<EOF
 159 /* Special handling for embedded SPU executables.  */
 160 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
 161 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
 162
 163 static bfd_boolean
 164 ppc_recognized_file (lang_input_statement_type *entry)
 165 {
 166   if (embedded_spu_file (entry, "-m32"))
 167     return TRUE;
 168
 169   return gld${EMULATION_NAME}_load_symbols (entry);
 170 }
 171
 172 EOF
 173 LDEMUL_RECOGNIZED_FILE=ppc_recognized_file
 174 fi
 175
 176 # Define some shell vars to insert bits of code into the standard elf
 177 # parse_args and list_options functions.
 178 #
 179 PARSE_AND_LIST_PROLOGUE='
 180 #define OPTION_NO_TLS_OPT               301
 181 #define OPTION_NO_TLS_GET_ADDR_OPT      (OPTION_NO_TLS_OPT + 1)
 182 #define OPTION_NEW_PLT                  (OPTION_NO_TLS_GET_ADDR_OPT + 1)
 183 #define OPTION_OLD_PLT                  (OPTION_NEW_PLT + 1)
 184 #define OPTION_OLD_GOT                  (OPTION_OLD_PLT + 1)
 185 #define OPTION_STUBSYMS                 (OPTION_OLD_GOT + 1)
 186 #define OPTION_NO_STUBSYMS              (OPTION_STUBSYMS + 1)
 187 '
 188
 189 PARSE_AND_LIST_LONGOPTS='
 190   { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
 191   { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
 192   { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
 193   { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
 194   { "secure-plt", no_argument, NULL, OPTION_NEW_PLT },
 195   { "bss-plt", no_argument, NULL, OPTION_OLD_PLT },
 196   { "sdata-got", no_argument, NULL, OPTION_OLD_GOT },
 197 '
 198
 199 PARSE_AND_LIST_OPTIONS='
 200   fprintf (file, _("\
 201   --emit-stub-syms            Label linker stubs with a symbol.\n\
 202   --no-emit-stub-syms         Don'\''t label linker stubs with a symbol.\n\
 203   --no-tls-optimize           Don'\''t try to optimize TLS accesses.\n\
 204   --no-tls-get-addr-optimize  Don'\''t use a special __tls_get_addr call.\n\
 205   --secure-plt                Use new-style PLT if possible.\n\
 206   --bss-plt                   Force old-style BSS PLT.\n\
 207   --sdata-got                 Force GOT location just before .sdata.\n"
 208                    ));
 209 '
 210
 211 PARSE_AND_LIST_ARGS_CASES='
 212     case OPTION_STUBSYMS:
 213       emit_stub_syms = 1;
 214       break;
 215
 216     case OPTION_NO_STUBSYMS:
 217       emit_stub_syms = 0;
 218       break;
 219
 220     case OPTION_NO_TLS_OPT:
 221       notlsopt = 1;
 222       break;
 223
 224     case OPTION_NO_TLS_GET_ADDR_OPT:
 225       no_tls_get_addr_opt = 1;
 226       break;
 227
 228     case OPTION_NEW_PLT:
 229       plt_style = PLT_NEW;
 230       break;
 231
 232     case OPTION_OLD_PLT:
 233       plt_style = PLT_OLD;
 234       break;
 235
 236     case OPTION_OLD_GOT:
 237       old_got = 1;
 238       break;
 239 '
 240
 241 # Put these extra ppc32elf routines in ld_${EMULATION_NAME}_emulation
 242 #
 243 LDEMUL_AFTER_OPEN=ppc_after_open
 244 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation