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2 Commits

Author SHA1 Message Date
H.J. Lu
16526e42c2 Add _bfd_elf_record_start_stop 2016-04-28 06:38:41 -07:00
H.J. Lu
316b611580 Add record_link_assignments to ldemul 2016-04-28 05:25:17 -07:00
7 changed files with 119 additions and 61 deletions

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@@ -2339,6 +2339,9 @@ extern bfd_boolean bfd_elf_gc_common_final_link
extern asection *_bfd_elf_is_start_stop
(const struct bfd_link_info *, struct elf_link_hash_entry *);
extern void _bfd_elf_record_start_stop
(const struct bfd_link_info *);
extern bfd_boolean bfd_elf_reloc_symbol_deleted_p
(bfd_vma, void *);

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@@ -13791,3 +13791,24 @@ elf_append_rel (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
BFD_ASSERT (loc + bed->s->sizeof_rel <= s->contents + s->size);
bed->s->swap_reloc_out (abfd, rel, loc);
}
/* For undefined __start_<name> and __stop_<name> symbols, set
def_regular to 1. This is called via elf_link_hash_traverse. */
static bfd_boolean
elf_link_record_start_stop (struct elf_link_hash_entry *h, void *data)
{
const struct bfd_link_info * info
= (const struct bfd_link_info *) data;
if (_bfd_elf_is_start_stop (info, h) != NULL)
h->def_regular = 1;
return TRUE;
}
void
_bfd_elf_record_start_stop (const struct bfd_link_info * info)
{
elf_link_hash_traverse (elf_hash_table (info),
elf_link_record_start_stop,
(void *) info);
}

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@@ -64,6 +64,7 @@ static void gld${EMULATION_NAME}_after_parse (void);
static void gld${EMULATION_NAME}_after_open (void);
static void gld${EMULATION_NAME}_before_allocation (void);
static void gld${EMULATION_NAME}_after_allocation (void);
static void gld${EMULATION_NAME}_restore_ehdr_start (void);
static lang_output_section_statement_type *gld${EMULATION_NAME}_place_orphan
(asection *, const char *, int);
EOF
@@ -1330,6 +1331,7 @@ fragment <<EOF
EOF
fi
if test x"$LDEMUL_RECORD_LINK_ASSIGNMENTS" != xgld"$EMULATION_NAME"_record_link_assignments; then
fragment <<EOF
/* Look through an expression for an assignment statement. */
@@ -1398,7 +1400,79 @@ gld${EMULATION_NAME}_find_statement_assignment (lang_statement_union_type *s)
gld${EMULATION_NAME}_find_exp_assignment (s->assignment_statement.exp);
}
static struct elf_link_hash_entry *ehdr_start;
static struct bfd_link_hash_entry ehdr_start_save;
static void
gld${EMULATION_NAME}_record_link_assignments (lang_phase_type phase)
{
if (phase == lang_mark_phase_enum
&& is_elf_hash_table (link_info.hash))
{
/* Make __ehdr_start hidden if it has been referenced, to
prevent the symbol from being dynamic. */
if (!bfd_link_relocatable (&link_info))
{
struct elf_link_hash_entry *h
= elf_link_hash_lookup (elf_hash_table (&link_info),
"__ehdr_start", FALSE, FALSE, TRUE);
/* Only adjust the export class if the symbol was referenced
and not defined, otherwise leave it alone. */
if (h != NULL
&& (h->root.type == bfd_link_hash_new
|| h->root.type == bfd_link_hash_undefined
|| h->root.type == bfd_link_hash_undefweak
|| h->root.type == bfd_link_hash_common))
{
_bfd_elf_link_hash_hide_symbol (&link_info, h, TRUE);
if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
/* Don't leave the symbol undefined. Undefined hidden
symbols typically won't have dynamic relocations, but
we most likely will need dynamic relocations for
__ehdr_start if we are building a PIE or shared
library. */
ehdr_start = h;
ehdr_start_save = h->root;
h->root.type = bfd_link_hash_defined;
h->root.u.def.section = bfd_abs_section_ptr;
h->root.u.def.value = 0;
}
}
/* If we are going to make any variable assignments, we need to
let the ELF backend know about them in case the variables are
referred to by dynamic objects. */
lang_for_each_statement (gld${EMULATION_NAME}_find_statement_assignment);
_bfd_elf_record_start_stop (&link_info);
}
}
static void
gld${EMULATION_NAME}_restore_ehdr_start (void)
{
if (ehdr_start != NULL)
{
/* If we twiddled __ehdr_start to defined earlier, put it back
as it was. */
ehdr_start->root.type = ehdr_start_save.type;
ehdr_start->root.u = ehdr_start_save.u;
}
}
EOF
else
fragment <<EOF
static
gld${EMULATION_NAME}_restore_ehdr_start (void)
{
}
EOF
fi
if test x"$LDEMUL_BEFORE_ALLOCATION" != xgld"$EMULATION_NAME"_before_allocation; then
if test x"${ELF_INTERPRETER_NAME+set}" = xset; then
@@ -1455,11 +1529,6 @@ gld${EMULATION_NAME}_append_to_separated_string (char **to, char *op_arg)
}
}
#if defined(__GNUC__) && GCC_VERSION < 4006
/* Work around a GCC uninitialized warning bug fixed in GCC 4.6. */
static struct bfd_link_hash_entry ehdr_start_empty;
#endif
/* This is called after the sections have been attached to output
sections, but before any sizes or addresses have been set. */
@@ -1469,55 +1538,9 @@ gld${EMULATION_NAME}_before_allocation (void)
const char *rpath;
asection *sinterp;
bfd *abfd;
struct elf_link_hash_entry *ehdr_start = NULL;
#if defined(__GNUC__) && GCC_VERSION < 4006
/* Work around a GCC uninitialized warning bug fixed in GCC 4.6. */
struct bfd_link_hash_entry ehdr_start_save = ehdr_start_empty;
#else
struct bfd_link_hash_entry ehdr_start_save;
#endif
if (is_elf_hash_table (link_info.hash))
{
_bfd_elf_tls_setup (link_info.output_bfd, &link_info);
/* Make __ehdr_start hidden if it has been referenced, to
prevent the symbol from being dynamic. */
if (!bfd_link_relocatable (&link_info))
{
struct elf_link_hash_entry *h
= elf_link_hash_lookup (elf_hash_table (&link_info), "__ehdr_start",
FALSE, FALSE, TRUE);
/* Only adjust the export class if the symbol was referenced
and not defined, otherwise leave it alone. */
if (h != NULL
&& (h->root.type == bfd_link_hash_new
|| h->root.type == bfd_link_hash_undefined
|| h->root.type == bfd_link_hash_undefweak
|| h->root.type == bfd_link_hash_common))
{
_bfd_elf_link_hash_hide_symbol (&link_info, h, TRUE);
if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
/* Don't leave the symbol undefined. Undefined hidden
symbols typically won't have dynamic relocations, but
we most likely will need dynamic relocations for
__ehdr_start if we are building a PIE or shared
library. */
ehdr_start = h;
ehdr_start_save = h->root;
h->root.type = bfd_link_hash_defined;
h->root.u.def.section = bfd_abs_section_ptr;
h->root.u.def.value = 0;
}
}
/* If we are going to make any variable assignments, we need to
let the ELF backend know about them in case the variables are
referred to by dynamic objects. */
lang_for_each_statement (gld${EMULATION_NAME}_find_statement_assignment);
}
_bfd_elf_tls_setup (link_info.output_bfd, &link_info);
/* Let the ELF backend work out the sizes of any sections required
by dynamic linking. */
@@ -1627,13 +1650,7 @@ ${ELF_INTERPRETER_SET_DEFAULT}
if (!bfd_elf_size_dynsym_hash_dynstr (link_info.output_bfd, &link_info))
einfo ("%P%F: failed to set dynamic section sizes: %E\n");
if (ehdr_start != NULL)
{
/* If we twiddled __ehdr_start to defined earlier, put it back
as it was. */
ehdr_start->root.type = ehdr_start_save.type;
ehdr_start->root.u = ehdr_start_save.u;
}
gld${EMULATION_NAME}_restore_ehdr_start ();
}
EOF
@@ -2527,6 +2544,7 @@ struct ld_emulation_xfer_struct ld_${EMULATION_NAME}_emulation =
${LDEMUL_RECOGNIZED_FILE-gld${EMULATION_NAME}_load_symbols},
${LDEMUL_FIND_POTENTIAL_LIBRARIES-NULL},
${LDEMUL_NEW_VERS_PATTERN-NULL},
${LDEMUL_EXTRA_MAP_FILE_TEXT-NULL}
${LDEMUL_EXTRA_MAP_FILE_TEXT-NULL},
${LDEMUL_RECORD_LINK_ASSIGNMENTS-gld${EMULATION_NAME}_record_link_assignments},
};
EOF

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@@ -206,6 +206,7 @@ struct ld_emulation_xfer_struct ld_${EMULATION_NAME}_emulation =
NULL, /* recognized file */
NULL, /* find_potential_libraries */
NULL, /* new_vers_pattern */
NULL /* extra_map_file_text */
NULL, /* extra_map_file_text */
NULL /* record_link_assignments */
};
EOF

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@@ -355,3 +355,10 @@ ldemul_extra_map_file_text (bfd *abfd, struct bfd_link_info *info, FILE *mapf)
if (ld_emulation->extra_map_file_text)
ld_emulation->extra_map_file_text (abfd, info, mapf);
}
void
ldemul_record_link_assignments (lang_phase_type phase)
{
if (ld_emulation->record_link_assignments)
ld_emulation->record_link_assignments (phase);
}

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@@ -96,6 +96,8 @@ extern struct bfd_elf_version_expr *ldemul_new_vers_pattern
(struct bfd_elf_version_expr *);
extern void ldemul_extra_map_file_text
(bfd *, struct bfd_link_info *, FILE *);
extern void ldemul_record_link_assignments
(lang_phase_type);
typedef struct ld_emulation_xfer_struct {
/* Run before parsing the command line and script file.
@@ -201,6 +203,10 @@ typedef struct ld_emulation_xfer_struct {
void (*extra_map_file_text)
(bfd *, struct bfd_link_info *, FILE *);
/* Called to record link assignments. */
void (*record_link_assignments)
(lang_phase_type);
} ld_emulation_xfer_type;
typedef enum {

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@@ -6930,6 +6930,8 @@ lang_process (void)
collection in order to make sure that all symbol aliases are resolved. */
lang_do_assignments (lang_mark_phase_enum);
ldemul_record_link_assignments (lang_mark_phase_enum);
lang_do_memory_regions();
expld.phase = lang_first_phase_enum;