ld/emultempl/ppc32elf.em

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