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 static int no_tls_get_addr_opt = 0;
  39
  40 /* Whether to emit symbols for stubs.  */
  41 static int emit_stub_syms = -1;
  42
  43 /* Chooses the correct place for .plt and .got.  */
  44 static enum ppc_elf_plt_type plt_style = PLT_UNSET;
  45 static int old_got = 0;
  46
  47 static void
  48 ppc_after_open (void)
  49 {
  50   if (is_ppc_elf (link_info.output_bfd))
  51     {
  52       int new_plt;
  53       int keep_new;
  54       unsigned int num_plt;
  55       unsigned int num_got;
  56       lang_output_section_statement_type *os;
  57       lang_output_section_statement_type *plt_os[2];
  58       lang_output_section_statement_type *got_os[2];
  59
  60       if (emit_stub_syms < 0)
  61         emit_stub_syms = link_info.emitrelocations || link_info.shared;
  62       new_plt = ppc_elf_select_plt_layout (link_info.output_bfd, &link_info,
  63                                            plt_style, emit_stub_syms);
  64       if (new_plt < 0)
  65         einfo ("%X%P: select_plt_layout problem %E\n");
  66
  67       num_got = 0;
  68       num_plt = 0;
  69       for (os = &lang_output_section_statement.head->output_section_statement;
  70            os != NULL;
  71            os = os->next)
  72         {
  73           if (os->constraint == SPECIAL && strcmp (os->name, ".plt") == 0)
  74             {
  75               if (num_plt < 2)
  76                 plt_os[num_plt] = os;
  77               ++num_plt;
  78             }
  79           if (os->constraint == SPECIAL && strcmp (os->name, ".got") == 0)
  80             {
  81               if (num_got < 2)
  82                 got_os[num_got] = os;
  83               ++num_got;
  84             }
  85         }
  86
  87       keep_new = new_plt == 1 ? 0 : -1;
  88       if (num_plt == 2)
  89         {
  90           plt_os[0]->constraint = keep_new;
  91           plt_os[1]->constraint = ~keep_new;
  92         }
  93       if (num_got == 2)
  94         {
  95           if (old_got)
  96             keep_new = -1;
  97           got_os[0]->constraint = keep_new;
  98           got_os[1]->constraint = ~keep_new;
  99         }
 100     }
 101
 102   gld${EMULATION_NAME}_after_open ();
 103 }
 104
 105 static void
 106 ppc_before_allocation (void)
 107 {
 108   if (is_ppc_elf (link_info.output_bfd))
 109     {
 110       if (ppc_elf_tls_setup (link_info.output_bfd, &link_info,
 111                              no_tls_get_addr_opt)
 112           && !notlsopt)
 113         {
 114           if (!ppc_elf_tls_optimize (link_info.output_bfd, &link_info))
 115             {
 116               einfo ("%X%P: TLS problem %E\n");
 117               return;
 118             }
 119         }
 120     }
 121
 122   gld${EMULATION_NAME}_before_allocation ();
 123
 124   /* Turn on relaxation if executable sections have addresses that
 125      might make branches overflow.  */
 126   if (RELAXATION_DISABLED_BY_DEFAULT)
 127     {
 128       bfd_vma low = (bfd_vma) -1;
 129       bfd_vma high = 0;
 130       asection *o;
 131
 132       /* Run lang_size_sections (if not already done).  */
 133       if (expld.phase != lang_mark_phase_enum)
 134         {
 135           expld.phase = lang_mark_phase_enum;
 136           expld.dataseg.phase = exp_dataseg_none;
 137           one_lang_size_sections_pass (NULL, FALSE);
 138           lang_reset_memory_regions ();
 139         }
 140
 141       for (o = link_info.output_bfd->sections; o != NULL; o = o->next)
 142         {
 143           if ((o->flags & (SEC_ALLOC | SEC_CODE)) != (SEC_ALLOC | SEC_CODE))
 144             continue;
 145           if (o->rawsize == 0)
 146             continue;
 147           if (low > o->vma)
 148             low = o->vma;
 149           if (high < o->vma + o->rawsize - 1)
 150             high = o->vma + o->rawsize - 1;
 151         }
 152       if (high > low && high - low > (1 << 25) - 1)
 153         ENABLE_RELAXATION;
 154     }
 155 }
 156
 157 EOF
 158
 159 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
 160   fragment <<EOF
 161 /* Special handling for embedded SPU executables.  */
 162 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
 163 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
 164
 165 static bfd_boolean
 166 ppc_recognized_file (lang_input_statement_type *entry)
 167 {
 168   if (embedded_spu_file (entry, "-m32"))
 169     return TRUE;
 170
 171   return gld${EMULATION_NAME}_load_symbols (entry);
 172 }
 173
 174 EOF
 175 LDEMUL_RECOGNIZED_FILE=ppc_recognized_file
 176 fi
 177
 178 # Define some shell vars to insert bits of code into the standard elf
 179 # parse_args and list_options functions.
 180 #
 181 PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}'
 182 #define OPTION_NO_TLS_OPT               321
 183 #define OPTION_NO_TLS_GET_ADDR_OPT      (OPTION_NO_TLS_OPT + 1)
 184 #define OPTION_NEW_PLT                  (OPTION_NO_TLS_GET_ADDR_OPT + 1)
 185 #define OPTION_OLD_PLT                  (OPTION_NEW_PLT + 1)
 186 #define OPTION_OLD_GOT                  (OPTION_OLD_PLT + 1)
 187 #define OPTION_STUBSYMS                 (OPTION_OLD_GOT + 1)
 188 #define OPTION_NO_STUBSYMS              (OPTION_STUBSYMS + 1)
 189 '
 190
 191 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
 192   { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
 193   { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
 194   { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
 195   { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
 196   { "secure-plt", no_argument, NULL, OPTION_NEW_PLT },
 197   { "bss-plt", no_argument, NULL, OPTION_OLD_PLT },
 198   { "sdata-got", no_argument, NULL, OPTION_OLD_GOT },
 199 '
 200
 201 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
 202   fprintf (file, _("\
 203   --emit-stub-syms            Label linker stubs with a symbol.\n\
 204   --no-emit-stub-syms         Don'\''t label linker stubs with a symbol.\n\
 205   --no-tls-optimize           Don'\''t try to optimize TLS accesses.\n\
 206   --no-tls-get-addr-optimize  Don'\''t use a special __tls_get_addr call.\n\
 207   --secure-plt                Use new-style PLT if possible.\n\
 208   --bss-plt                   Force old-style BSS PLT.\n\
 209   --sdata-got                 Force GOT location just before .sdata.\n"
 210                    ));
 211 '
 212
 213 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
 214     case OPTION_STUBSYMS:
 215       emit_stub_syms = 1;
 216       break;
 217
 218     case OPTION_NO_STUBSYMS:
 219       emit_stub_syms = 0;
 220       break;
 221
 222     case OPTION_NO_TLS_OPT:
 223       notlsopt = 1;
 224       break;
 225
 226     case OPTION_NO_TLS_GET_ADDR_OPT:
 227       no_tls_get_addr_opt = 1;
 228       break;
 229
 230     case OPTION_NEW_PLT:
 231       plt_style = PLT_NEW;
 232       break;
 233
 234     case OPTION_OLD_PLT:
 235       plt_style = PLT_OLD;
 236       break;
 237
 238     case OPTION_OLD_GOT:
 239       old_got = 1;
 240       break;
 241
 242     case OPTION_TRADITIONAL_FORMAT:
 243       notlsopt = 1;
 244       no_tls_get_addr_opt = 1;
 245       return FALSE;
 246 '
 247
 248 # Put these extra ppc32elf routines in ld_${EMULATION_NAME}_emulation
 249 #
 250 LDEMUL_AFTER_OPEN=ppc_after_open
 251 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation