Add support for 64-bit ARM architecture: AArch64

1 files changed, 415 insertions, 0 deletions

diff --git a/ld/emultempl/aarch64elf.em b/ld/emultempl/aarch64elf.em
new file mode 100644
index 0000000000..4c03ffd449
--- /dev/null
+++ b/ld/emultempl/aarch64elf.em
@@ -0,0 +1,415 @@
+# This shell script emits a C file. -*- C -*-
+#   Copyright 2009-2012  Free Software Foundation, Inc.
+#   Contributed by ARM Ltd.
+#
+# This file is part of the GNU Binutils.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the license, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING3. If not,
+# see <http://www.gnu.org/licenses/>.
+#
+
+# This file is sourced from elf32.em, and defines extra aarch64-elf
+# specific routines.
+#
+fragment <<EOF
+
+#include "ldctor.h"
+#include "elf/aarch64.h"
+
+static int no_enum_size_warning = 0;
+static int no_wchar_size_warning = 0;
+static int pic_veneer = 0;
+
+static void
+gld${EMULATION_NAME}_before_parse (void)
+{
+#ifndef TARGET_			/* I.e., if not generic.  */
+  ldfile_set_output_arch ("`echo ${ARCH}`", bfd_arch_unknown);
+#endif /* not TARGET_ */
+  input_flags.dynamic = ${DYNAMIC_LINK-TRUE};
+  config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo TRUE ; else echo FALSE ; fi`;
+}
+
+static void
+aarch64_elf_before_allocation (void)
+{
+  /* We should be able to set the size of the interworking stub section.  We
+     can't do it until later if we have dynamic sections, though.  */
+  if (! elf_hash_table (&link_info)->dynamic_sections_created)
+    {
+      /* Here we rummage through the found bfds to collect information.  */
+      LANG_FOR_EACH_INPUT_STATEMENT (is)
+	{
+          /* Initialise mapping tables for code/data.  */
+          bfd_elf64_aarch64_init_maps (is->the_bfd);
+	}
+    }
+
+  /* Call the standard elf routine.  */
+  gld${EMULATION_NAME}_before_allocation ();
+}
+
+/* Fake input file for stubs.  */
+static lang_input_statement_type *stub_file;
+
+/* Whether we need to call gldarm_layout_sections_again.  */
+static int need_laying_out = 0;
+
+/* Maximum size of a group of input sections that can be handled by
+   one stub section.  A value of +/-1 indicates the bfd back-end
+   should use a suitable default size.  */
+static bfd_signed_vma group_size = 1;
+
+struct hook_stub_info
+{
+  lang_statement_list_type add;
+  asection *input_section;
+};
+
+/* Traverse the linker tree to find the spot where the stub goes.  */
+
+static bfd_boolean
+hook_in_stub (struct hook_stub_info *info, lang_statement_union_type **lp)
+{
+  lang_statement_union_type *l;
+  bfd_boolean ret;
+
+  for (; (l = *lp) != NULL; lp = &l->header.next)
+    {
+      switch (l->header.type)
+	{
+	case lang_constructors_statement_enum:
+	  ret = hook_in_stub (info, &constructor_list.head);
+	  if (ret)
+	    return ret;
+	  break;
+
+	case lang_output_section_statement_enum:
+	  ret = hook_in_stub (info,
+			      &l->output_section_statement.children.head);
+	  if (ret)
+	    return ret;
+	  break;
+
+	case lang_wild_statement_enum:
+	  ret = hook_in_stub (info, &l->wild_statement.children.head);
+	  if (ret)
+	    return ret;
+	  break;
+
+	case lang_group_statement_enum:
+	  ret = hook_in_stub (info, &l->group_statement.children.head);
+	  if (ret)
+	    return ret;
+	  break;
+
+	case lang_input_section_enum:
+	  if (l->input_section.section == info->input_section)
+	    {
+	      /* We've found our section.  Insert the stub immediately
+		 after its associated input section.  */
+	      *(info->add.tail) = l->header.next;
+	      l->header.next = info->add.head;
+	      return TRUE;
+	    }
+	  break;
+
+	case lang_data_statement_enum:
+	case lang_reloc_statement_enum:
+	case lang_object_symbols_statement_enum:
+	case lang_output_statement_enum:
+	case lang_target_statement_enum:
+	case lang_input_statement_enum:
+	case lang_assignment_statement_enum:
+	case lang_padding_statement_enum:
+	case lang_address_statement_enum:
+	case lang_fill_statement_enum:
+	  break;
+
+	default:
+	  FAIL ();
+	  break;
+	}
+    }
+  return FALSE;
+}
+
+
+/* Call-back for elf64_aarch64_size_stubs.  */
+
+/* Create a new stub section, and arrange for it to be linked
+   immediately after INPUT_SECTION.  */
+
+static asection *
+elf64_aarch64_add_stub_section (const char *stub_sec_name,
+				asection *input_section)
+{
+  asection *stub_sec;
+  flagword flags;
+  asection *output_section;
+  const char *secname;
+  lang_output_section_statement_type *os;
+  struct hook_stub_info info;
+
+  flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
+	   | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
+  stub_sec = bfd_make_section_anyway_with_flags (stub_file->the_bfd,
+						 stub_sec_name, flags);
+  if (stub_sec == NULL)
+    goto err_ret;
+
+  bfd_set_section_alignment (stub_file->the_bfd, stub_sec, 3);
+
+  output_section = input_section->output_section;
+  secname = bfd_get_section_name (output_section->owner, output_section);
+  os = lang_output_section_find (secname);
+
+  info.input_section = input_section;
+  lang_list_init (&info.add);
+  lang_add_section (&info.add, stub_sec, NULL, os);
+
+  if (info.add.head == NULL)
+    goto err_ret;
+
+  if (hook_in_stub (&info, &os->children.head))
+    return stub_sec;
+
+ err_ret:
+  einfo ("%X%P: can not make stub section: %E\n");
+  return NULL;
+}
+
+/* Another call-back for elf_arm_size_stubs.  */
+
+static void
+gldaarch64_layout_sections_again (void)
+{
+  /* If we have changed sizes of the stub sections, then we need
+     to recalculate all the section offsets.  This may mean we need to
+     add even more stubs.  */
+  gld${EMULATION_NAME}_map_segments (TRUE);
+  need_laying_out = -1;
+}
+
+static void
+build_section_lists (lang_statement_union_type *statement)
+{
+  if (statement->header.type == lang_input_section_enum)
+    {
+      asection *i = statement->input_section.section;
+
+      if (!((lang_input_statement_type *) i->owner->usrdata)->flags.just_syms
+	  && (i->flags & SEC_EXCLUDE) == 0
+	  && i->output_section != NULL
+	  && i->output_section->owner == link_info.output_bfd)
+	elf64_aarch64_next_input_section (& link_info, i);
+    }
+}
+
+static void
+gld${EMULATION_NAME}_after_allocation (void)
+{
+  /* bfd_elf32_discard_info just plays with debugging sections,
+     ie. doesn't affect any code, so we can delay resizing the
+     sections.  It's likely we'll resize everything in the process of
+     adding stubs.  */
+  if (bfd_elf_discard_info (link_info.output_bfd, & link_info))
+    need_laying_out = 1;
+
+  /* If generating a relocatable output file, then we don't
+     have to examine the relocs.  */
+  if (stub_file != NULL && !link_info.relocatable)
+    {
+      int ret = elf64_aarch64_setup_section_lists (link_info.output_bfd,
+						   & link_info);
+
+      if (ret != 0)
+	{
+	  if (ret < 0)
+	    {
+	      einfo ("%X%P: could not compute sections lists for stub generation: %E\n");
+	      return;
+	    }
+
+	  lang_for_each_statement (build_section_lists);
+
+	  /* Call into the BFD backend to do the real work.  */
+	  if (! elf64_aarch64_size_stubs (link_info.output_bfd,
+					  stub_file->the_bfd,
+					  & link_info,
+					  group_size,
+					  & elf64_aarch64_add_stub_section,
+					  & gldaarch64_layout_sections_again))
+	    {
+	      einfo ("%X%P: cannot size stub section: %E\n");
+	      return;
+	    }
+	}
+    }
+
+  if (need_laying_out != -1)
+    gld${EMULATION_NAME}_map_segments (need_laying_out);
+}
+
+static void
+gld${EMULATION_NAME}_finish (void)
+{
+  if (! link_info.relocatable)
+    {
+      /* Now build the linker stubs.  */
+      if (stub_file->the_bfd->sections != NULL)
+	{
+	  if (! elf64_aarch64_build_stubs (& link_info))
+	    einfo ("%X%P: can not build stubs: %E\n");
+	}
+    }
+
+  finish_default ();
+}
+
+/* This is a convenient point to tell BFD about target specific flags.
+   After the output has been created, but before inputs are read.  */
+static void
+aarch64_elf_create_output_section_statements (void)
+{
+  if (strstr (bfd_get_target (link_info.output_bfd), "aarch64") == NULL)
+    {
+      /* The arm backend needs special fields in the output hash structure.
+	 These will only be created if the output format is an arm format,
+	 hence we do not support linking and changing output formats at the
+	 same time.  Use a link followed by objcopy to change output formats.  */
+      einfo ("%F%X%P: error: Cannot change output format whilst linking AArch64 binaries.\n");
+      return;
+    }
+
+  bfd_elf64_aarch64_set_options (link_info.output_bfd, &link_info,
+				 no_enum_size_warning,
+				 no_wchar_size_warning,
+				 pic_veneer);
+
+  stub_file = lang_add_input_file ("linker stubs",
+				   lang_input_file_is_fake_enum,
+				   NULL);
+  stub_file->the_bfd = bfd_create ("linker stubs", link_info.output_bfd);
+  if (stub_file->the_bfd == NULL
+      || ! bfd_set_arch_mach (stub_file->the_bfd,
+			      bfd_get_arch (link_info.output_bfd),
+			      bfd_get_mach (link_info.output_bfd)))
+    {
+      einfo ("%X%P: can not create BFD %E\n");
+      return;
+    }
+
+  stub_file->the_bfd->flags |= BFD_LINKER_CREATED;
+  ldlang_add_file (stub_file);
+}
+
+/* Avoid processing the fake stub_file in vercheck, stat_needed and
+   check_needed routines.  */
+
+static void (*real_func) (lang_input_statement_type *);
+
+static void aarch64_for_each_input_file_wrapper (lang_input_statement_type *l)
+{
+  if (l != stub_file)
+    (*real_func) (l);
+}
+
+static void
+aarch64_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
+{
+  real_func = func;
+  lang_for_each_input_file (&aarch64_for_each_input_file_wrapper);
+}
+
+#define lang_for_each_input_file aarch64_lang_for_each_input_file
+
+EOF
+
+# Define some shell vars to insert bits of code into the standard elf
+# parse_args and list_options functions.
+#
+PARSE_AND_LIST_PROLOGUE='
+#define OPTION_NO_ENUM_SIZE_WARNING	309
+#define OPTION_PIC_VENEER		310
+#define OPTION_STUBGROUP_SIZE           311
+#define OPTION_NO_WCHAR_SIZE_WARNING	312
+'
+
+PARSE_AND_LIST_SHORTOPTS=p
+
+PARSE_AND_LIST_LONGOPTS='
+  { "no-pipeline-knowledge", no_argument, NULL, '\'p\''},
+  { "no-enum-size-warning", no_argument, NULL, OPTION_NO_ENUM_SIZE_WARNING},
+  { "pic-veneer", no_argument, NULL, OPTION_PIC_VENEER},
+  { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE },
+  { "no-wchar-size-warning", no_argument, NULL, OPTION_NO_WCHAR_SIZE_WARNING},
+'
+
+PARSE_AND_LIST_OPTIONS='
+  fprintf (file, _("  --no-enum-size-warning      Don'\''t warn about objects with incompatible\n"
+		   "                                enum sizes\n"));
+  fprintf (file, _("  --no-wchar-size-warning     Don'\''t warn about objects with incompatible"
+		   "                                wchar_t sizes\n"));
+  fprintf (file, _("  --pic-veneer                Always generate PIC interworking veneers\n"));
+  fprintf (file, _("\
+   --stub-group-size=N   Maximum size of a group of input sections that can be\n\
+                           handled by one stub section.  A negative value\n\
+                           locates all stubs after their branches (with a\n\
+                           group size of -N), while a positive value allows\n\
+                           two groups of input sections, one before, and one\n\
+                           after each stub section.  Values of +/-1 indicate\n\
+                           the linker should choose suitable defaults.\n"
+		   ));
+'
+
+PARSE_AND_LIST_ARGS_CASES='
+    case '\'p\'':
+      /* Only here for backwards compatibility.  */
+      break;
+
+    case OPTION_NO_ENUM_SIZE_WARNING:
+      no_enum_size_warning = 1;
+      break;
+
+    case OPTION_NO_WCHAR_SIZE_WARNING:
+      no_wchar_size_warning = 1;
+      break;
+
+    case OPTION_PIC_VENEER:
+      pic_veneer = 1;
+      break;
+
+    case OPTION_STUBGROUP_SIZE:
+      {
+	const char *end;
+
+        group_size = bfd_scan_vma (optarg, &end, 0);
+        if (*end)
+	  einfo (_("%P%F: invalid number `%s'\''\n"), optarg);
+      }
+      break;
+'
+
+# We have our own before_allocation etc. functions, but they call
+# the standard routines, so give them a different name.
+LDEMUL_BEFORE_ALLOCATION=aarch64_elf_before_allocation
+LDEMUL_AFTER_ALLOCATION=gld${EMULATION_NAME}_after_allocation
+LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=aarch64_elf_create_output_section_statements
+
+# Replace the elf before_parse function with our own.
+LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
+
+# Call the extra arm-elf function
+LDEMUL_FINISH=gld${EMULATION_NAME}_finish