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-rw-r--r--ld/emultempl/armelf.em274
1 files changed, 270 insertions, 4 deletions
diff --git a/ld/emultempl/armelf.em b/ld/emultempl/armelf.em
index 29e9902..57842f4 100644
--- a/ld/emultempl/armelf.em
+++ b/ld/emultempl/armelf.em
@@ -27,6 +27,7 @@
test -z "$TARGET2_TYPE" && TARGET2_TYPE="rel"
fragment <<EOF
+#include "ldctor.h"
#include "elf/arm.h"
static char *thumb_entry_symbol = NULL;
@@ -173,13 +174,221 @@ arm_elf_after_allocation (void)
}
}
+/* 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
+ before its associated input section. */
+ *lp = info->add.head;
+ *(info->add.tail) = l;
+ 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 elf32_arm_size_stubs. */
+
+/* Create a new stub section, and arrange for it to be linked
+ immediately before INPUT_SECTION. */
+
+static asection *
+elf32_arm_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;
+
+ stub_sec = bfd_make_section_anyway (stub_file->the_bfd, stub_sec_name);
+ if (stub_sec == NULL)
+ goto err_ret;
+
+ flags = (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
+ | SEC_HAS_CONTENTS | SEC_RELOC | SEC_IN_MEMORY | SEC_KEEP);
+ if (!bfd_set_section_flags (stub_file->the_bfd, stub_sec, flags))
+ 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, 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
-arm_elf_finish (void)
+gldarm_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)->just_syms_flag
+ && (i->flags & SEC_EXCLUDE) == 0
+ && i->output_section != NULL
+ && i->output_section->owner == link_info.output_bfd)
+ elf32_arm_next_input_section (& link_info, i);
+ }
+}
+
+static void
+gld${EMULATION_NAME}_finish (void)
{
struct bfd_link_hash_entry * h;
- /* Call the elf32.em routine. */
- gld${EMULATION_NAME}_finish ();
+ /* 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 = elf32_arm_setup_section_lists (link_info.output_bfd, & link_info);
+
+ if (ret != 0)
+ {
+ if (ret < 0)
+ {
+ einfo ("%X%P: can not size stub section: %E\n");
+ return;
+ }
+
+ lang_for_each_statement (build_section_lists);
+
+ /* Call into the BFD backend to do the real work. */
+ if (! elf32_arm_size_stubs (link_info.output_bfd,
+ stub_file->the_bfd,
+ & link_info,
+ group_size,
+ & elf32_arm_add_stub_section,
+ & gldarm_layout_sections_again))
+ {
+ einfo ("%X%P: can not size stub section: %E\n");
+ return;
+ }
+ }
+ }
+
+ if (need_laying_out != -1)
+ gld${EMULATION_NAME}_map_segments (need_laying_out);
+
+ if (! link_info.relocatable)
+ {
+ /* Now build the linker stubs. */
+ if (stub_file->the_bfd->sections != NULL)
+ {
+ if (! elf32_arm_build_stubs (& link_info))
+ einfo ("%X%P: can not build stubs: %E\n");
+ }
+ }
+
+ finish_default ();
if (thumb_entry_symbol)
{
@@ -246,8 +455,44 @@ arm_elf_create_output_section_statements (void)
target2_type, fix_v4bx, use_blx,
vfp11_denorm_fix, no_enum_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 arm_for_each_input_file_wrapper (lang_input_statement_type *l)
+{
+ if (l != stub_file)
+ (*real_func) (l);
}
+static void
+arm_lang_for_each_input_file (void (*func) (lang_input_statement_type *))
+{
+ real_func = func;
+ lang_for_each_input_file (&arm_for_each_input_file_wrapper);
+}
+
+#define lang_for_each_input_file arm_lang_for_each_input_file
+
EOF
# Define some shell vars to insert bits of code into the standard elf
@@ -265,6 +510,7 @@ PARSE_AND_LIST_PROLOGUE='
#define OPTION_NO_ENUM_SIZE_WARNING 309
#define OPTION_PIC_VENEER 310
#define OPTION_FIX_V4BX_INTERWORKING 311
+#define OPTION_STUBGROUP_SIZE 312
'
PARSE_AND_LIST_SHORTOPTS=p
@@ -282,6 +528,7 @@ PARSE_AND_LIST_LONGOPTS='
{ "vfp11-denorm-fix", required_argument, NULL, OPTION_VFP11_DENORM_FIX},
{ "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 },
'
PARSE_AND_LIST_OPTIONS='
@@ -297,6 +544,15 @@ PARSE_AND_LIST_OPTIONS='
fprintf (file, _(" --no-enum-size-warning Don'\''t warn about objects with incompatible"
" enum 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 before 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='
@@ -354,6 +610,16 @@ PARSE_AND_LIST_ARGS_CASES='
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 after_open and before_allocation functions, but they call
@@ -367,4 +633,4 @@ LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=arm_elf_create_output_section_statements
LDEMUL_BEFORE_PARSE=gld"${EMULATION_NAME}"_before_parse
# Call the extra arm-elf function
-LDEMUL_FINISH=arm_elf_finish
+LDEMUL_FINISH=gld${EMULATION_NAME}_finish
generated by cgit v1.1 at 2024-12-19 01:29:45 +0000