-/* Copyright (C) 1991 Free Software Foundation, Inc.
+/* ldwrite.c -- write out the linked file
+ Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 2000, 2002,
+ 2003, 2004 Free Software Foundation, Inc.
+ Written by Steve Chamberlain sac@cygnus.com
This file is part of GLD, the Gnu Linker.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
-
-/*
- This module writes out the final image by reading sections from the
- input files, relocating them and writing them out
-
- There are two main paths through this module, one for normal
- operation and one for partial linking.
-
- During normal operation, raw section data is read along with the
- associated relocation information, the relocation info applied and
- the section data written out on a section by section basis.
-
- When partially linking, all the relocation records are read to work
- out how big the output relocation vector will be. Then raw data is
- read, relocated and written section by section.
-
- Written by Steve Chamberlain sac@cygnus.com
-
-*/
-
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "bfd.h"
#include "sysdep.h"
+#include "bfdlink.h"
+#include "libiberty.h"
+#include "safe-ctype.h"
#include "ld.h"
#include "ldexp.h"
#include "ldlang.h"
#include "ldwrite.h"
#include "ldmisc.h"
-#include "ldsym.h"
-#include "ldgram.h"
+#include <ldgram.h>
#include "ldmain.h"
-#include "relax.h"
+
+/* Build link_order structures for the BFD linker. */
static void
-read_relocs (abfd, section, symbols)
- bfd * abfd;
- asection * section;
- asymbol ** symbols;
+build_link_order (lang_statement_union_type *statement)
{
- /* Work out the output section ascociated with this input section */
- asection *output_section = section->output_section;
+ switch (statement->header.type)
+ {
+ case lang_data_statement_enum:
+ {
+ asection *output_section;
+ struct bfd_link_order *link_order;
+ bfd_vma value;
+ bfd_boolean big_endian = FALSE;
+
+ output_section = statement->data_statement.output_section;
+ ASSERT (output_section->owner == output_bfd);
+
+ link_order = bfd_new_link_order (output_bfd, output_section);
+ if (link_order == NULL)
+ einfo (_("%P%F: bfd_new_link_order failed\n"));
+
+ link_order->type = bfd_data_link_order;
+ link_order->offset = statement->data_statement.output_vma;
+ link_order->u.data.contents = xmalloc (QUAD_SIZE);
+
+ value = statement->data_statement.value;
+
+ /* If the endianness of the output BFD is not known, then we
+ base the endianness of the data on the first input file.
+ By convention, the bfd_put routines for an unknown
+ endianness are big endian, so we must swap here if the
+ input file is little endian. */
+ if (bfd_big_endian (output_bfd))
+ big_endian = TRUE;
+ else if (bfd_little_endian (output_bfd))
+ big_endian = FALSE;
+ else
+ {
+ bfd_boolean swap;
+
+ swap = FALSE;
+ if (command_line.endian == ENDIAN_BIG)
+ big_endian = TRUE;
+ else if (command_line.endian == ENDIAN_LITTLE)
+ {
+ big_endian = FALSE;
+ swap = TRUE;
+ }
+ else if (command_line.endian == ENDIAN_UNSET)
+ {
+ big_endian = TRUE;
+ {
+ LANG_FOR_EACH_INPUT_STATEMENT (s)
+ {
+ if (s->the_bfd != NULL)
+ {
+ if (bfd_little_endian (s->the_bfd))
+ {
+ big_endian = FALSE;
+ swap = TRUE;
+ }
+ break;
+ }
+ }
+ }
+ }
+
+ if (swap)
+ {
+ bfd_byte buffer[8];
+
+ switch (statement->data_statement.type)
+ {
+ case QUAD:
+ case SQUAD:
+ if (sizeof (bfd_vma) >= QUAD_SIZE)
+ {
+ bfd_putl64 (value, buffer);
+ value = bfd_getb64 (buffer);
+ break;
+ }
+ /* Fall through. */
+ case LONG:
+ bfd_putl32 (value, buffer);
+ value = bfd_getb32 (buffer);
+ break;
+ case SHORT:
+ bfd_putl16 (value, buffer);
+ value = bfd_getb16 (buffer);
+ break;
+ case BYTE:
+ break;
+ default:
+ abort ();
+ }
+ }
+ }
+
+ ASSERT (output_section->owner == output_bfd);
+ switch (statement->data_statement.type)
+ {
+ case QUAD:
+ case SQUAD:
+ if (sizeof (bfd_vma) >= QUAD_SIZE)
+ bfd_put_64 (output_bfd, value, link_order->u.data.contents);
+ else
+ {
+ bfd_vma high;
+
+ if (statement->data_statement.type == QUAD)
+ high = 0;
+ else if ((value & 0x80000000) == 0)
+ high = 0;
+ else
+ high = (bfd_vma) -1;
+ bfd_put_32 (output_bfd, high,
+ (link_order->u.data.contents
+ + (big_endian ? 0 : 4)));
+ bfd_put_32 (output_bfd, value,
+ (link_order->u.data.contents
+ + (big_endian ? 4 : 0)));
+ }
+ link_order->size = QUAD_SIZE;
+ break;
+ case LONG:
+ bfd_put_32 (output_bfd, value, link_order->u.data.contents);
+ link_order->size = LONG_SIZE;
+ break;
+ case SHORT:
+ bfd_put_16 (output_bfd, value, link_order->u.data.contents);
+ link_order->size = SHORT_SIZE;
+ break;
+ case BYTE:
+ bfd_put_8 (output_bfd, value, link_order->u.data.contents);
+ link_order->size = BYTE_SIZE;
+ break;
+ default:
+ abort ();
+ }
+ }
+ break;
- bfd_size_type reloc_size = bfd_get_reloc_upper_bound (abfd, section);
- arelent **reloc_vector = (arelent **) ldmalloc (reloc_size);
+ case lang_reloc_statement_enum:
+ {
+ lang_reloc_statement_type *rs;
+ asection *output_section;
+ struct bfd_link_order *link_order;
- if (bfd_canonicalize_reloc (abfd,
- section,
- reloc_vector,
- symbols))
+ rs = &statement->reloc_statement;
+
+ output_section = rs->output_section;
+ ASSERT (output_section->owner == output_bfd);
+
+ link_order = bfd_new_link_order (output_bfd, output_section);
+ if (link_order == NULL)
+ einfo (_("%P%F: bfd_new_link_order failed\n"));
+
+ link_order->offset = rs->output_vma;
+ link_order->size = bfd_get_reloc_size (rs->howto);
+
+ link_order->u.reloc.p = xmalloc (sizeof (struct bfd_link_order_reloc));
+
+ link_order->u.reloc.p->reloc = rs->reloc;
+ link_order->u.reloc.p->addend = rs->addend_value;
+
+ if (rs->name == NULL)
+ {
+ link_order->type = bfd_section_reloc_link_order;
+ if (rs->section->owner == output_bfd)
+ link_order->u.reloc.p->u.section = rs->section;
+ else
+ {
+ link_order->u.reloc.p->u.section = rs->section->output_section;
+ link_order->u.reloc.p->addend += rs->section->output_offset;
+ }
+ }
+ else
+ {
+ link_order->type = bfd_symbol_reloc_link_order;
+ link_order->u.reloc.p->u.name = rs->name;
+ }
+ }
+ break;
+
+ case lang_input_section_enum:
+ /* Create a new link_order in the output section with this
+ attached */
+ if (!statement->input_section.ifile->just_syms_flag
+ && (statement->input_section.section->flags & SEC_EXCLUDE) == 0)
+ {
+ asection *i = statement->input_section.section;
+ asection *output_section = i->output_section;
+
+ ASSERT (output_section->owner == output_bfd);
+
+ if ((output_section->flags & SEC_HAS_CONTENTS) != 0
+ || ((output_section->flags & SEC_LOAD) != 0
+ && (output_section->flags & SEC_THREAD_LOCAL)))
+ {
+ struct bfd_link_order *link_order;
+
+ link_order = bfd_new_link_order (output_bfd, output_section);
+
+ if (i->flags & SEC_NEVER_LOAD)
+ {
+ /* We've got a never load section inside one which
+ is going to be output, we'll change it into a
+ fill. */
+ link_order->type = bfd_data_link_order;
+ link_order->u.data.contents = "";
+ link_order->u.data.size = 1;
+ }
+ else
+ {
+ link_order->type = bfd_indirect_link_order;
+ link_order->u.indirect.section = i;
+ ASSERT (i->output_section == output_section);
+ }
+ link_order->size = i->size;
+ link_order->offset = i->output_offset;
+ }
+ }
+ break;
+
+ case lang_padding_statement_enum:
+ /* Make a new link_order with the right filler */
+ {
+ asection *output_section;
+ struct bfd_link_order *link_order;
+
+ output_section = statement->padding_statement.output_section;
+ ASSERT (statement->padding_statement.output_section->owner
+ == output_bfd);
+ if ((output_section->flags & SEC_HAS_CONTENTS) != 0)
+ {
+ link_order = bfd_new_link_order (output_bfd, output_section);
+ link_order->type = bfd_data_link_order;
+ link_order->size = statement->padding_statement.size;
+ link_order->offset = statement->padding_statement.output_offset;
+ link_order->u.data.contents = statement->padding_statement.fill->data;
+ link_order->u.data.size = statement->padding_statement.fill->size;
+ }
+ }
+ break;
+
+ default:
+ /* All the other ones fall through */
+ break;
+ }
+}
+
+/* Return true if NAME is the name of an unsplittable section. These
+ are the stabs strings, dwarf strings. */
+
+static bfd_boolean
+unsplittable_name (const char *name)
+{
+ if (strncmp (name, ".stab", 5) == 0)
{
- output_section->reloc_count += section->reloc_count;
+ /* There are several stab like string sections. We pattern match on
+ ".stab...str" */
+ unsigned len = strlen (name);
+ if (strcmp (&name[len-3], "str") == 0)
+ return TRUE;
}
+ else if (strcmp (name, "$GDB_STRINGS$") == 0)
+ return TRUE;
+ return FALSE;
}
+/* Wander around the input sections, make sure that
+ we'll never try and create an output section with more relocs
+ than will fit.. Do this by always assuming the worst case, and
+ creating new output sections with all the right bits. */
+#define TESTIT 1
+static asection *
+clone_section (bfd *abfd, asection *s, const char *name, int *count)
+{
+ char *tname;
+ char *sname;
+ unsigned int len;
+ asection *n;
+ struct bfd_link_hash_entry *h;
+
+ /* Invent a section name from the section name and a dotted numeric
+ suffix. */
+ len = strlen (name);
+ tname = xmalloc (len + 1);
+ memcpy (tname, name, len + 1);
+ /* Remove a dotted number suffix, from a previous split link. */
+ while (len && ISDIGIT (tname[len-1]))
+ len--;
+ if (len > 1 && tname[len-1] == '.')
+ /* It was a dotted number. */
+ tname[len-1] = 0;
+
+ /* We want to use the whole of the original section name for the
+ split name, but coff can be restricted to 8 character names. */
+ if (bfd_family_coff (abfd) && strlen (tname) > 5)
+ {
+ /* Some section names cannot be truncated, as the name is
+ used to locate some other section. */
+ if (strncmp (name, ".stab", 5) == 0
+ || strcmp (name, "$GDB_SYMBOLS$") == 0)
+ {
+ einfo (_ ("%F%P: cannot create split section name for %s\n"), name);
+ /* Silence gcc warnings. einfo exits, so we never reach here. */
+ return NULL;
+ }
+ tname[5] = 0;
+ }
+
+ if ((sname = bfd_get_unique_section_name (abfd, tname, count)) == NULL
+ || (n = bfd_make_section_anyway (abfd, sname)) == NULL
+ || (h = bfd_link_hash_lookup (link_info.hash,
+ sname, TRUE, TRUE, FALSE)) == NULL)
+ {
+ einfo (_("%F%P: clone section failed: %E\n"));
+ /* Silence gcc warnings. einfo exits, so we never reach here. */
+ return NULL;
+ }
+ free (tname);
+
+ /* Set up section symbol. */
+ h->type = bfd_link_hash_defined;
+ h->u.def.value = 0;
+ h->u.def.section = n;
+
+ n->flags = s->flags;
+ n->vma = s->vma;
+ n->user_set_vma = s->user_set_vma;
+ n->lma = s->lma;
+ n->size = 0;
+ n->output_offset = s->output_offset;
+ n->output_section = n;
+ n->orelocation = 0;
+ n->reloc_count = 0;
+ n->alignment_power = s->alignment_power;
+ return n;
+}
+
+#if TESTING
+static void
+ds (asection *s)
+{
+ struct bfd_link_order *l = s->link_order_head;
+ printf ("vma %x size %x\n", s->vma, s->size);
+ while (l)
+ {
+ if (l->type == bfd_indirect_link_order)
+ {
+ printf ("%8x %s\n", l->offset, l->u.indirect.section->owner->filename);
+ }
+ else
+ {
+ printf (_("%8x something else\n"), l->offset);
+ }
+ l = l->next;
+ }
+ printf ("\n");
+}
+
+dump (char *s, asection *a1, asection *a2)
+{
+ printf ("%s\n", s);
+ ds (a1);
+ ds (a2);
+}
static void
-setup_rel ()
+sanity_check (bfd *abfd)
{
- /*
- Run through each section of each file and work work out the total
- number of relocation records which will finally be in each output
- section
- */
-
- LANG_FOR_EACH_INPUT_SECTION
- (statement, abfd, section,
- (read_relocs (abfd, section, statement->asymbols)));
-
-
-
- /*
- Now run though all the output sections and allocate the space for
- all the relocations
- */
- LANG_FOR_EACH_OUTPUT_SECTION
- (section,
- (section->orelocation =
- (arelent **) ldmalloc ((bfd_size_type) (sizeof (arelent **) *
- section->reloc_count)),
- section->reloc_count = 0));
+ asection *s;
+ for (s = abfd->sections; s; s = s->next)
+ {
+ struct bfd_link_order *p;
+ bfd_vma prev = 0;
+ for (p = s->link_order_head; p; p = p->next)
+ {
+ if (p->offset > 100000)
+ abort ();
+ if (p->offset < prev)
+ abort ();
+ prev = p->offset;
+ }
+ }
}
+#else
+#define sanity_check(a)
+#define dump(a, b, c)
+#endif
-void
-ldwrite ()
+static void
+split_sections (bfd *abfd, struct bfd_link_info *info)
{
- PTR data_area = (PTR) ldmalloc (largest_section);
+ asection *original_sec;
+ int nsecs = abfd->section_count;
+ sanity_check (abfd);
+ /* Look through all the original sections. */
+ for (original_sec = abfd->sections;
+ original_sec && nsecs;
+ original_sec = original_sec->next, nsecs--)
+ {
+ int count = 0;
+ unsigned int lines = 0;
+ unsigned int relocs = 0;
+ bfd_size_type sec_size = 0;
+ struct bfd_link_order *l;
+ struct bfd_link_order *p;
+ bfd_vma vma = original_sec->vma;
+ asection *cursor = original_sec;
+
+ /* Count up the relocations and line entries to see if anything
+ would be too big to fit. Accumulate section size too. */
+ for (l = NULL, p = cursor->link_order_head; p != NULL; p = l->next)
+ {
+ unsigned int thislines = 0;
+ unsigned int thisrelocs = 0;
+ bfd_size_type thissize = 0;
+ if (p->type == bfd_indirect_link_order)
+ {
+ asection *sec;
+
+ sec = p->u.indirect.section;
+
+ if (info->strip == strip_none
+ || info->strip == strip_some)
+ thislines = sec->lineno_count;
+
+ if (info->relocatable)
+ thisrelocs = sec->reloc_count;
+
+ thissize = sec->size;
+
+ }
+ else if (info->relocatable
+ && (p->type == bfd_section_reloc_link_order
+ || p->type == bfd_symbol_reloc_link_order))
+ thisrelocs++;
+
+ if (l != NULL
+ && (thisrelocs + relocs >= config.split_by_reloc
+ || thislines + lines >= config.split_by_reloc
+ || (thissize + sec_size >= config.split_by_file))
+ && !unsplittable_name (cursor->name))
+ {
+ /* Create a new section and put this link order and the
+ following link orders into it. */
+ bfd_vma shift_offset;
+ asection *n;
+
+ n = clone_section (abfd, cursor, original_sec->name, &count);
- ldsym_write ();
+ /* Attach the link orders to the new section and snip
+ them off from the old section. */
+ n->link_order_head = p;
+ n->link_order_tail = cursor->link_order_tail;
+ cursor->link_order_tail = l;
+ l->next = NULL;
+ l = p;
- if (config.relocateable_output == true)
- setup_rel ();
+ /* Change the size of the original section and
+ update the vma of the new one. */
- write_relax (output_bfd, data_area, config.relocateable_output);
+ dump ("before snip", cursor, n);
- free (data_area);
+ shift_offset = p->offset;
+ n->size = cursor->size - shift_offset;
+ cursor->size = shift_offset;
- /* Output the symbol table (both globals and locals). */
+ vma += shift_offset;
+ n->lma = n->vma = vma;
- /* Print a map, if requested and possible. */
+ /* Run down the chain and change the output section to
+ the right one, update the offsets too. */
+ do
+ {
+ p->offset -= shift_offset;
+ if (p->type == bfd_indirect_link_order)
+ {
+ p->u.indirect.section->output_section = n;
+ p->u.indirect.section->output_offset = p->offset;
+ }
+ p = p->next;
+ }
+ while (p);
- if (config.map_file)
- {
- ldsym_print_symbol_table ();
- lang_map ();
- }
+ dump ("after snip", cursor, n);
+ cursor = n;
+ relocs = thisrelocs;
+ lines = thislines;
+ sec_size = thissize;
+ }
+ else
+ {
+ l = p;
+ relocs += thisrelocs;
+ lines += thislines;
+ sec_size += thissize;
+ }
+ }
+ }
+ sanity_check (abfd);
+}
+
+/* Call BFD to write out the linked file. */
+
+void
+ldwrite (void)
+{
+ /* Reset error indicator, which can typically something like invalid
+ format from opening up the .o files. */
+ bfd_set_error (bfd_error_no_error);
+ lang_for_each_statement (build_link_order);
+
+ if (config.split_by_reloc != (unsigned) -1
+ || config.split_by_file != (bfd_size_type) -1)
+ split_sections (output_bfd, &link_info);
+ if (!bfd_final_link (output_bfd, &link_info))
+ {
+ /* If there was an error recorded, print it out. Otherwise assume
+ an appropriate error message like unknown symbol was printed
+ out. */
+
+ if (bfd_get_error () != bfd_error_no_error)
+ einfo (_("%F%P: final link failed: %E\n"));
+ else
+ xexit (1);
+ }
}