ld/emultempl/mmo.em

   1 # This shell script emits a C file. -*- C -*-
   2 #   Copyright 2001 Free Software Foundation, Inc.
   3 #
   4 # This file is part of GLD, the Gnu Linker.
   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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19 #
  20
  21 # This file is sourced from elf32.em and mmo.em, used to define
  22 # linker MMIX-specifics common to ELF and MMO.
  23
  24 . ${srcdir}/emultempl/mmix-elfnmmo.em
  25
  26 cat >>e${EMULATION_NAME}.c <<EOF
  27
  28 static boolean mmo_place_orphan
  29   PARAMS ((lang_input_statement_type *, asection *));
  30 static asection *output_prev_sec_find
  31   PARAMS ((lang_output_section_statement_type *));
  32 static void mmo_finish PARAMS ((void));
  33 static void mmo_wipe_sec_reloc_flag PARAMS ((bfd *, asection *, PTR));
  34
  35 /* Find the last output section before given output statement.
  36    Used by place_orphan.  */
  37
  38 static asection *
  39 output_prev_sec_find (os)
  40      lang_output_section_statement_type *os;
  41 {
  42   asection *s = (asection *) NULL;
  43   lang_statement_union_type *u;
  44   lang_output_section_statement_type *lookup;
  45
  46   for (u = lang_output_section_statement.head;
  47        u != (lang_statement_union_type *) NULL;
  48        u = lookup->next)
  49     {
  50       lookup = &u->output_section_statement;
  51       if (lookup == os)
  52         break;
  53       if (lookup->bfd_section != NULL
  54           && lookup->bfd_section != bfd_abs_section_ptr
  55           && lookup->bfd_section != bfd_com_section_ptr
  56           && lookup->bfd_section != bfd_und_section_ptr)
  57         s = lookup->bfd_section;
  58     }
  59
  60   if (u == NULL)
  61     return NULL;
  62
  63   return s;
  64 }
  65
  66 struct orphan_save {
  67   lang_output_section_statement_type *os;
  68   asection **section;
  69   lang_statement_union_type **stmt;
  70 };
  71
  72 #define HAVE_SECTION(hold, name) \
  73 (hold.os != NULL || (hold.os = lang_output_section_find (name)) != NULL)
  74
  75 /* Place an orphan section.  We use this to put random SEC_CODE or
  76    SEC_READONLY sections right after MMO_TEXT_SECTION_NAME.  Much borrowed
  77    from elf32.em.  */
  78
  79 static boolean
  80 mmo_place_orphan (file, s)
  81         lang_input_statement_type *file;
  82         asection *s;
  83 {
  84   static struct orphan_save hold_text;
  85   struct orphan_save *place;
  86   lang_output_section_statement_type *os;
  87   lang_statement_list_type *old;
  88   lang_statement_list_type add;
  89   asection *snew, **pps, *bfd_section;
  90
  91   /* We have nothing to say for anything other than a final link.  */
  92   if (link_info.relocateable
  93       || (bfd_get_section_flags (s->owner, s)
  94           & (SEC_EXCLUDE | SEC_LOAD)) != SEC_LOAD)
  95     return false;
  96
  97   /* Only care for sections we're going to load.  */
  98   os = lang_output_section_find (bfd_get_section_name (s->owner, s));
  99
 100   /* We have an output section by this name.  Place the section inside it
 101      (regardless of whether the linker script lists it as input).  */
 102   if (os != NULL)
 103     {
 104       lang_add_section (&os->children, s, os, file);
 105       return true;
 106     }
 107
 108   /* If this section does not have .text-type section flags or there's no
 109      MMO_TEXT_SECTION_NAME, we don't have anything to say.  */
 110   if ((bfd_get_section_flags (s->owner, s) & (SEC_CODE | SEC_READONLY)) == 0)
 111     return false;
 112
 113   if (hold_text.os == NULL)
 114     hold_text.os = lang_output_section_find (MMO_TEXT_SECTION_NAME);
 115
 116   place = &hold_text;
 117
 118   /* If there's an output section by this name, we'll use it, regardless
 119      of section flags, in contrast to what's done in elf32.em.  */
 120
 121   /* Start building a list of statements for this section.
 122      First save the current statement pointer.  */
 123   old = stat_ptr;
 124
 125   /* Add the output section statements for this orphan to our own private
 126      list, inserting them later into the global statement list.  */
 127   stat_ptr = &add;
 128   lang_list_init (stat_ptr);
 129
 130   os = lang_enter_output_section_statement (bfd_get_section_name (s->owner,
 131                                                                   s),
 132                                             NULL, 0,
 133                                             (bfd_vma) 0,
 134                                             (etree_type *) NULL,
 135                                             (etree_type *) NULL,
 136                                             (etree_type *) NULL);
 137
 138   lang_add_section (&os->children, s, os, file);
 139
 140   lang_leave_output_section_statement
 141     ((bfd_vma) 0, "*default*",
 142      (struct lang_output_section_phdr_list *) NULL, "*default*");
 143
 144   /* Restore the global list pointer.  */
 145   stat_ptr = old;
 146
 147   snew = os->bfd_section;
 148   bfd_section = place->os->bfd_section;
 149   if (place->section == NULL && bfd_section == NULL)
 150     bfd_section = output_prev_sec_find (place->os);
 151
 152   if (place->section != NULL
 153       || (bfd_section != NULL
 154           && bfd_section != snew))
 155     {
 156       /* Shuffle the section to make the output file look neater.  This is
 157          really only cosmetic.  */
 158       if (place->section == NULL)
 159         /* Put orphans after the first section on the list.  */
 160         place->section = &bfd_section->next;
 161
 162       /*  Unlink the section.  */
 163       for (pps = &output_bfd->sections; *pps != snew; pps = &(*pps)->next)
 164         ;
 165       *pps = snew->next;
 166
 167       /* Now tack it on to the "place->os" section list.  */
 168       snew->next = *place->section;
 169       *place->section = snew;
 170     }
 171   place->section = &snew->next; /* Save the end of this list.  */
 172
 173   if (add.head != NULL)
 174     {
 175       /* We try to put the output statements in some sort of reasonable
 176          order here, because they determine the final load addresses of
 177          the orphan sections.  */
 178       if (place->stmt == NULL)
 179         {
 180           /* Put the new statement list right at the head.  */
 181           *add.tail = place->os->header.next;
 182           place->os->header.next = add.head;
 183         }
 184       else
 185         {
 186           /* Put it after the last orphan statement we added.  */
 187           *add.tail = *place->stmt;
 188           *place->stmt = add.head;
 189         }
 190
 191       /* Fix the global list pointer if we happened to tack our new list
 192          at the tail.  */
 193       if (*old->tail == add.head)
 194         old->tail = add.tail;
 195
 196       /* Save the end of this list.  */
 197       place->stmt = add.tail;
 198     }
 199
 200   return true;
 201 }
 202
 203 /* Remove the spurious settings of SEC_RELOC that make it to the output at
 204    link time.  We are as confused as elflink.h:elf_bfd_final_link, and
 205    paper over the bug similarly.  */
 206
 207 static void
 208 mmo_wipe_sec_reloc_flag (abfd, sec, ptr)
 209      bfd *abfd;
 210      asection *sec;
 211      PTR ptr ATTRIBUTE_UNUSED;
 212 {
 213   bfd_set_section_flags (abfd, sec,
 214                          bfd_get_section_flags (abfd, sec) & ~SEC_RELOC);
 215 }
 216
 217 /* Iterate with bfd_map_over_sections over mmo_wipe_sec_reloc_flag... */
 218
 219 static void
 220 mmo_finish ()
 221 {
 222   bfd_map_over_sections (output_bfd, mmo_wipe_sec_reloc_flag, NULL);
 223 }
 224
 225 EOF
 226
 227 LDEMUL_PLACE_ORPHAN=mmo_place_orphan
 228 LDEMUL_FINISH=mmo_finish