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 bfd_vma pagesize = 0;
  43
  44 static struct ppc_elf_params params = { PLT_UNSET, -1, 0, 0, 0, 0 };
  45
  46 static void
  47 ppc_after_open_output (void)
  48 {
  49   if (params.emit_stub_syms < 0)
  50     params.emit_stub_syms = link_info.emitrelocations || link_info.shared;
  51   if (pagesize == 0)
  52     pagesize = config.commonpagesize;
  53   params.pagesize_p2 = bfd_log2 (pagesize);
  54   ppc_elf_link_params (&link_info, &params);
  55 }
  56
  57 static void
  58 ppc_after_open (void)
  59 {
  60   if (is_ppc_elf (link_info.output_bfd))
  61     {
  62       int new_plt;
  63       int keep_new;
  64       unsigned int num_plt;
  65       unsigned int num_got;
  66       lang_output_section_statement_type *os;
  67       lang_output_section_statement_type *plt_os[2];
  68       lang_output_section_statement_type *got_os[2];
  69
  70       new_plt = ppc_elf_select_plt_layout (link_info.output_bfd, &link_info);
  71       if (new_plt < 0)
  72         einfo ("%X%P: select_plt_layout problem %E\n");
  73
  74       num_got = 0;
  75       num_plt = 0;
  76       for (os = &lang_output_section_statement.head->output_section_statement;
  77            os != NULL;
  78            os = os->next)
  79         {
  80           if (os->constraint == SPECIAL && strcmp (os->name, ".plt") == 0)
  81             {
  82               if (num_plt < 2)
  83                 plt_os[num_plt] = os;
  84               ++num_plt;
  85             }
  86           if (os->constraint == SPECIAL && strcmp (os->name, ".got") == 0)
  87             {
  88               if (num_got < 2)
  89                 got_os[num_got] = os;
  90               ++num_got;
  91             }
  92         }
  93
  94       keep_new = new_plt == 1 ? 0 : -1;
  95       if (num_plt == 2)
  96         {
  97           plt_os[0]->constraint = keep_new;
  98           plt_os[1]->constraint = ~keep_new;
  99         }
 100       if (num_got == 2)
 101         {
 102           if (old_got)
 103             keep_new = -1;
 104           got_os[0]->constraint = keep_new;
 105           got_os[1]->constraint = ~keep_new;
 106         }
 107     }
 108
 109   gld${EMULATION_NAME}_after_open ();
 110 }
 111
 112 static void
 113 ppc_before_allocation (void)
 114 {
 115   if (is_ppc_elf (link_info.output_bfd))
 116     {
 117       if (ppc_elf_tls_setup (link_info.output_bfd, &link_info)
 118           && !notlsopt)
 119         {
 120           if (!ppc_elf_tls_optimize (link_info.output_bfd, &link_info))
 121             {
 122               einfo ("%X%P: TLS problem %E\n");
 123               return;
 124             }
 125         }
 126     }
 127
 128   gld${EMULATION_NAME}_before_allocation ();
 129
 130   if (RELAXATION_ENABLED)
 131     params.branch_trampolines = 1;
 132
 133   /* Turn on relaxation if executable sections have addresses that
 134      might make branches overflow.  */
 135   else if (!RELAXATION_DISABLED_BY_USER)
 136     {
 137       bfd_vma low = (bfd_vma) -1;
 138       bfd_vma high = 0;
 139       asection *o;
 140
 141       /* Run lang_size_sections (if not already done).  */
 142       if (expld.phase != lang_mark_phase_enum)
 143         {
 144           expld.phase = lang_mark_phase_enum;
 145           expld.dataseg.phase = exp_dataseg_none;
 146           one_lang_size_sections_pass (NULL, FALSE);
 147           lang_reset_memory_regions ();
 148         }
 149
 150       for (o = link_info.output_bfd->sections; o != NULL; o = o->next)
 151         {
 152           if ((o->flags & (SEC_ALLOC | SEC_CODE)) != (SEC_ALLOC | SEC_CODE))
 153             continue;
 154           if (o->rawsize == 0)
 155             continue;
 156           if (low > o->vma)
 157             low = o->vma;
 158           if (high < o->vma + o->rawsize - 1)
 159             high = o->vma + o->rawsize - 1;
 160         }
 161       if (high > low && high - low > (1 << 25) - 1)
 162         params.branch_trampolines = 1;
 163     }
 164
 165   if (params.ppc476_workaround || params.branch_trampolines)
 166     ENABLE_RELAXATION;
 167 }
 168
 169 EOF
 170
 171 if grep -q 'ld_elf32_spu_emulation' ldemul-list.h; then
 172   fragment <<EOF
 173 /* Special handling for embedded SPU executables.  */
 174 extern bfd_boolean embedded_spu_file (lang_input_statement_type *, const char *);
 175 static bfd_boolean gld${EMULATION_NAME}_load_symbols (lang_input_statement_type *);
 176
 177 static bfd_boolean
 178 ppc_recognized_file (lang_input_statement_type *entry)
 179 {
 180   if (embedded_spu_file (entry, "-m32"))
 181     return TRUE;
 182
 183   return gld${EMULATION_NAME}_load_symbols (entry);
 184 }
 185
 186 EOF
 187 LDEMUL_RECOGNIZED_FILE=ppc_recognized_file
 188 fi
 189
 190 # Define some shell vars to insert bits of code into the standard elf
 191 # parse_args and list_options functions.
 192 #
 193 PARSE_AND_LIST_PROLOGUE=${PARSE_AND_LIST_PROLOGUE}'
 194 #define OPTION_NO_TLS_OPT               321
 195 #define OPTION_NO_TLS_GET_ADDR_OPT      (OPTION_NO_TLS_OPT + 1)
 196 #define OPTION_NEW_PLT                  (OPTION_NO_TLS_GET_ADDR_OPT + 1)
 197 #define OPTION_OLD_PLT                  (OPTION_NEW_PLT + 1)
 198 #define OPTION_OLD_GOT                  (OPTION_OLD_PLT + 1)
 199 #define OPTION_STUBSYMS                 (OPTION_OLD_GOT + 1)
 200 #define OPTION_NO_STUBSYMS              (OPTION_STUBSYMS + 1)
 201 #define OPTION_PPC476_WORKAROUND        (OPTION_NO_STUBSYMS + 1)
 202 #define OPTION_NO_PPC476_WORKAROUND     (OPTION_PPC476_WORKAROUND + 1)
 203 '
 204
 205 PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
 206   { "emit-stub-syms", no_argument, NULL, OPTION_STUBSYMS },
 207   { "no-emit-stub-syms", no_argument, NULL, OPTION_NO_STUBSYMS },
 208   { "no-tls-optimize", no_argument, NULL, OPTION_NO_TLS_OPT },
 209   { "no-tls-get-addr-optimize", no_argument, NULL, OPTION_NO_TLS_GET_ADDR_OPT },
 210   { "secure-plt", no_argument, NULL, OPTION_NEW_PLT },
 211   { "bss-plt", no_argument, NULL, OPTION_OLD_PLT },
 212   { "sdata-got", no_argument, NULL, OPTION_OLD_GOT },
 213   { "ppc476-workaround", optional_argument, NULL, OPTION_PPC476_WORKAROUND },
 214   { "no-ppc476-workaround", no_argument, NULL, OPTION_NO_PPC476_WORKAROUND },
 215 '
 216
 217 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
 218   fprintf (file, _("\
 219   --emit-stub-syms            Label linker stubs with a symbol.\n\
 220   --no-emit-stub-syms         Don'\''t label linker stubs with a symbol.\n\
 221   --no-tls-optimize           Don'\''t try to optimize TLS accesses.\n\
 222   --no-tls-get-addr-optimize  Don'\''t use a special __tls_get_addr call.\n\
 223   --secure-plt                Use new-style PLT if possible.\n\
 224   --bss-plt                   Force old-style BSS PLT.\n\
 225   --sdata-got                 Force GOT location just before .sdata.\n\
 226   --ppc476-workaround [=pagesize]\n\
 227                               Avoid a cache bug on ppc476.\n\
 228   --no-ppc476-workaround      Disable workaround.\n"
 229                    ));
 230 '
 231
 232 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
 233     case OPTION_STUBSYMS:
 234       params.emit_stub_syms = 1;
 235       break;
 236
 237     case OPTION_NO_STUBSYMS:
 238       params.emit_stub_syms = 0;
 239       break;
 240
 241     case OPTION_NO_TLS_OPT:
 242       notlsopt = 1;
 243       break;
 244
 245     case OPTION_NO_TLS_GET_ADDR_OPT:
 246       params.no_tls_get_addr_opt = 1;
 247       break;
 248
 249     case OPTION_NEW_PLT:
 250       params.plt_style = PLT_NEW;
 251       break;
 252
 253     case OPTION_OLD_PLT:
 254       params.plt_style = PLT_OLD;
 255       break;
 256
 257     case OPTION_OLD_GOT:
 258       old_got = 1;
 259       break;
 260
 261     case OPTION_TRADITIONAL_FORMAT:
 262       notlsopt = 1;
 263       params.no_tls_get_addr_opt = 1;
 264       return FALSE;
 265
 266     case OPTION_PPC476_WORKAROUND:
 267       params.ppc476_workaround = 1;
 268       if (optarg != NULL)
 269         {
 270           char *end;
 271           pagesize = strtoul (optarg, &end, 0);
 272           if (*end
 273               || (pagesize < 4096 && pagesize != 0)
 274               || pagesize != (pagesize & -pagesize))
 275             einfo (_("%P%F: invalid pagesize `%s'\''\n"), optarg);
 276         }
 277       break;
 278
 279     case OPTION_NO_PPC476_WORKAROUND:
 280       params.ppc476_workaround = 0;
 281       break;
 282 '
 283
 284 # Put these extra ppc32elf routines in ld_${EMULATION_NAME}_emulation
 285 #
 286 LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=ppc_after_open_output
 287 LDEMUL_AFTER_OPEN=ppc_after_open
 288 LDEMUL_BEFORE_ALLOCATION=ppc_before_allocation