// layout.cc -- lay out output file sections for gold
-// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
+// Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
#include "symtab.h"
#include "dynobj.h"
#include "ehframe.h"
+#include "gdb-index.h"
#include "compressed_output.h"
#include "reduced_debug_output.h"
+#include "object.h"
#include "reloc.h"
#include "descriptors.h"
#include "plugin.h"
Free_list::allocate(off_t len, uint64_t align, off_t minoff)
{
gold_debug(DEBUG_INCREMENTAL,
- "Free_list::allocate(%08lx, %d, %08lx)",
- static_cast<long>(len), static_cast<int>(align),
- static_cast<long>(minoff));
+ "Free_list::allocate(%08lx, %d, %08lx)",
+ static_cast<long>(len), static_cast<int>(align),
+ static_cast<long>(minoff));
if (len == 0)
return align_address(minoff, align);
++Free_list::num_allocates;
+ // We usually want to drop free chunks smaller than 4 bytes.
+ // If we need to guarantee a minimum hole size, though, we need
+ // to keep track of all free chunks.
+ const int fuzz = this->min_hole_ > 0 ? 0 : 3;
+
for (Iterator p = this->list_.begin(); p != this->list_.end(); ++p)
{
++Free_list::num_allocate_visits;
off_t start = p->start_ > minoff ? p->start_ : minoff;
start = align_address(start, align);
off_t end = start + len;
- if (end <= p->end_)
+ if (end > p->end_ && p->end_ == this->length_ && this->extend_)
{
- if (p->start_ + 3 >= start && p->end_ <= end + 3)
+ this->length_ = end;
+ p->end_ = end;
+ }
+ if (end == p->end_ || (end <= p->end_ - this->min_hole_))
+ {
+ if (p->start_ + fuzz >= start && p->end_ <= end + fuzz)
this->list_.erase(p);
- else if (p->start_ + 3 >= start)
+ else if (p->start_ + fuzz >= start)
p->start_ = end;
- else if (p->end_ <= end + 3)
+ else if (p->end_ <= end + fuzz)
p->end_ = start;
else
{
return start;
}
}
+ if (this->extend_)
+ {
+ off_t start = align_address(this->length_, align);
+ this->length_ = start + len;
+ return start;
+ }
return -1;
}
Free_list::print_stats()
{
fprintf(stderr, _("%s: total free lists: %u\n"),
- program_name, Free_list::num_lists);
+ program_name, Free_list::num_lists);
fprintf(stderr, _("%s: total free list nodes: %u\n"),
- program_name, Free_list::num_nodes);
+ program_name, Free_list::num_nodes);
fprintf(stderr, _("%s: calls to Free_list::remove: %u\n"),
- program_name, Free_list::num_removes);
+ program_name, Free_list::num_removes);
fprintf(stderr, _("%s: nodes visited: %u\n"),
- program_name, Free_list::num_remove_visits);
+ program_name, Free_list::num_remove_visits);
fprintf(stderr, _("%s: calls to Free_list::allocate: %u\n"),
- program_name, Free_list::num_allocates);
+ program_name, Free_list::num_allocates);
fprintf(stderr, _("%s: nodes visited: %u\n"),
- program_name, Free_list::num_allocate_visits);
+ program_name, Free_list::num_allocate_visits);
+}
+
+// A Hash_task computes the MD5 checksum of an array of char.
+// It has a blocker on either side (i.e., the task cannot run until
+// the first is unblocked, and it unblocks the second after running).
+
+class Hash_task : public Task
+{
+ public:
+ Hash_task(const unsigned char* src,
+ size_t size,
+ unsigned char* dst,
+ Task_token* build_id_blocker,
+ Task_token* final_blocker)
+ : src_(src), size_(size), dst_(dst), build_id_blocker_(build_id_blocker),
+ final_blocker_(final_blocker)
+ { }
+
+ void
+ run(Workqueue*)
+ { md5_buffer(reinterpret_cast<const char*>(src_), size_, dst_); }
+
+ Task_token*
+ is_runnable();
+
+ // Unblock FINAL_BLOCKER_ when done.
+ void
+ locks(Task_locker* tl)
+ { tl->add(this, this->final_blocker_); }
+
+ std::string
+ get_name() const
+ { return "Hash_task"; }
+
+ private:
+ const unsigned char* const src_;
+ const size_t size_;
+ unsigned char* const dst_;
+ Task_token* const build_id_blocker_;
+ Task_token* const final_blocker_;
+};
+
+Task_token*
+Hash_task::is_runnable()
+{
+ if (this->build_id_blocker_->is_blocked())
+ return this->build_id_blocker_;
+ return NULL;
}
// Layout::Relaxation_debug_check methods.
void
Layout::Relaxation_debug_check::check_output_data_for_reset_values(
const Layout::Section_list& sections,
- const Layout::Data_list& special_outputs)
+ const Layout::Data_list& special_outputs,
+ const Layout::Data_list& relax_outputs)
{
for(Layout::Section_list::const_iterator p = sections.begin();
p != sections.end();
p != special_outputs.end();
++p)
gold_assert((*p)->address_and_file_offset_have_reset_values());
+
+ gold_assert(relax_outputs.empty());
}
-
+
// Save information of SECTIONS for checking later.
void
void
Layout_task_runner::run(Workqueue* workqueue, const Task* task)
{
+ // See if any of the input definitions violate the One Definition Rule.
+ // TODO: if this is too slow, do this as a task, rather than inline.
+ this->symtab_->detect_odr_violations(task, this->options_.output_file_name());
+
Layout* layout = this->layout_;
off_t file_size = layout->finalize(this->input_objects_,
this->symtab_,
- this->target_,
+ this->target_,
task);
// Now we know the final size of the output file and we know where
// incremental information from the file before (possibly)
// overwriting it.
if (parameters->incremental_update())
- layout->incremental_base()->apply_incremental_relocs(this->symtab_,
- this->layout_,
+ layout->incremental_base()->apply_incremental_relocs(this->symtab_,
+ this->layout_,
of);
of->resize(file_size);
section_list_(),
unattached_section_list_(),
special_output_list_(),
+ relax_output_list_(),
section_headers_(NULL),
tls_segment_(NULL),
relro_segment_(NULL),
+ interp_segment_(NULL),
increase_relro_(0),
symtab_section_(NULL),
symtab_xindex_(NULL),
eh_frame_data_(NULL),
added_eh_frame_data_(false),
eh_frame_hdr_section_(NULL),
+ gdb_index_data_(NULL),
build_id_note_(NULL),
+ array_of_hashes_(NULL),
+ size_of_array_of_hashes_(0),
+ input_view_(NULL),
debug_abbrev_(NULL),
debug_info_(NULL),
group_signatures_(),
any_postprocessing_sections_(false),
resized_signatures_(false),
have_stabstr_section_(false),
+ section_ordering_specified_(false),
+ unique_segment_for_sections_specified_(false),
incremental_inputs_(NULL),
record_output_section_data_from_script_(false),
script_output_section_data_list_(),
segment_states_(NULL),
relaxation_debug_check_(NULL),
+ section_order_map_(),
+ section_segment_map_(),
+ input_section_position_(),
+ input_section_glob_(),
incremental_base_(NULL),
free_list_()
{
return k.first + k.second.first + k.second.second;
}
-// Returns whether the given section is in the list of
-// debug-sections-used-by-some-version-of-gdb. Currently,
-// we've checked versions of gdb up to and including 6.7.1.
+// These are the debug sections that are actually used by gdb.
+// Currently, we've checked versions of gdb up to and including 7.4.
+// We only check the part of the name that follows ".debug_" or
+// ".zdebug_".
static const char* gdb_sections[] =
-{ ".debug_abbrev",
- // ".debug_aranges", // not used by gdb as of 6.7.1
- ".debug_frame",
- ".debug_info",
- ".debug_types",
- ".debug_line",
- ".debug_loc",
- ".debug_macinfo",
- // ".debug_pubnames", // not used by gdb as of 6.7.1
- ".debug_ranges",
- ".debug_str",
+{
+ "abbrev",
+ "addr", // Fission extension
+ // "aranges", // not used by gdb as of 7.4
+ "frame",
+ "info",
+ "types",
+ "line",
+ "loc",
+ "macinfo",
+ "macro",
+ // "pubnames", // not used by gdb as of 7.4
+ // "pubtypes", // not used by gdb as of 7.4
+ "ranges",
+ "str",
};
+// This is the minimum set of sections needed for line numbers.
+
static const char* lines_only_debug_sections[] =
-{ ".debug_abbrev",
- // ".debug_aranges", // not used by gdb as of 6.7.1
- // ".debug_frame",
- ".debug_info",
- // ".debug_types",
- ".debug_line",
- // ".debug_loc",
- // ".debug_macinfo",
- // ".debug_pubnames", // not used by gdb as of 6.7.1
- // ".debug_ranges",
- ".debug_str",
+{
+ "abbrev",
+ // "addr", // Fission extension
+ // "aranges", // not used by gdb as of 7.4
+ // "frame",
+ "info",
+ // "types",
+ "line",
+ // "loc",
+ // "macinfo",
+ // "macro",
+ // "pubnames", // not used by gdb as of 7.4
+ // "pubtypes", // not used by gdb as of 7.4
+ // "ranges",
+ "str",
};
+// These sections are the DWARF fast-lookup tables, and are not needed
+// when building a .gdb_index section.
+
+static const char* gdb_fast_lookup_sections[] =
+{
+ "aranges",
+ "pubnames",
+ "pubtypes",
+};
+
+// Returns whether the given debug section is in the list of
+// debug-sections-used-by-some-version-of-gdb. SUFFIX is the
+// portion of the name following ".debug_" or ".zdebug_".
+
static inline bool
-is_gdb_debug_section(const char* str)
+is_gdb_debug_section(const char* suffix)
{
// We can do this faster: binary search or a hashtable. But why bother?
for (size_t i = 0; i < sizeof(gdb_sections)/sizeof(*gdb_sections); ++i)
- if (strcmp(str, gdb_sections[i]) == 0)
+ if (strcmp(suffix, gdb_sections[i]) == 0)
return true;
return false;
}
+// Returns whether the given section is needed for lines-only debugging.
+
static inline bool
-is_lines_only_debug_section(const char* str)
+is_lines_only_debug_section(const char* suffix)
{
// We can do this faster: binary search or a hashtable. But why bother?
for (size_t i = 0;
i < sizeof(lines_only_debug_sections)/sizeof(*lines_only_debug_sections);
++i)
- if (strcmp(str, lines_only_debug_sections[i]) == 0)
+ if (strcmp(suffix, lines_only_debug_sections[i]) == 0)
+ return true;
+ return false;
+}
+
+// Returns whether the given section is a fast-lookup section that
+// will not be needed when building a .gdb_index section.
+
+static inline bool
+is_gdb_fast_lookup_section(const char* suffix)
+{
+ // We can do this faster: binary search or a hashtable. But why bother?
+ for (size_t i = 0;
+ i < sizeof(gdb_fast_lookup_sections)/sizeof(*gdb_fast_lookup_sections);
+ ++i)
+ if (strcmp(suffix, gdb_fast_lookup_sections[i]) == 0)
return true;
return false;
}
Layout::include_section(Sized_relobj_file<size, big_endian>*, const char* name,
const elfcpp::Shdr<size, big_endian>& shdr)
{
- if (shdr.get_sh_flags() & elfcpp::SHF_EXCLUDE)
+ if (!parameters->options().relocatable()
+ && (shdr.get_sh_flags() & elfcpp::SHF_EXCLUDE))
return false;
switch (shdr.get_sh_type())
case elfcpp::SHT_GROUP:
// If we are emitting relocations these should be handled
// elsewhere.
- gold_assert(!parameters->options().relocatable()
- && !parameters->options().emit_relocs());
+ gold_assert(!parameters->options().relocatable());
return false;
case elfcpp::SHT_PROGBITS:
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
{
// Debugging sections can only be recognized by name.
- if (is_prefix_of(".debug", name)
- && !is_lines_only_debug_section(name))
+ if (is_prefix_of(".debug_", name)
+ && !is_lines_only_debug_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && !is_lines_only_debug_section(name + 8))
return false;
}
if (parameters->options().strip_debug_gdb()
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
{
// Debugging sections can only be recognized by name.
- if (is_prefix_of(".debug", name)
- && !is_gdb_debug_section(name))
+ if (is_prefix_of(".debug_", name)
+ && !is_gdb_debug_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && !is_gdb_debug_section(name + 8))
+ return false;
+ }
+ if (parameters->options().gdb_index()
+ && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
+ {
+ // When building .gdb_index, we can strip .debug_pubnames,
+ // .debug_pubtypes, and .debug_aranges sections.
+ if (is_prefix_of(".debug_", name)
+ && is_gdb_fast_lookup_section(name + 7))
+ return false;
+ if (is_prefix_of(".zdebug_", name)
+ && is_gdb_fast_lookup_section(name + 8))
return false;
}
if (parameters->options().strip_lto_sections()
- && !parameters->options().relocatable()
- && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
- {
- // Ignore LTO sections containing intermediate code.
- if (is_prefix_of(".gnu.lto_", name))
- return false;
- }
+ && !parameters->options().relocatable()
+ && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
+ {
+ // Ignore LTO sections containing intermediate code.
+ if (is_prefix_of(".gnu.lto_", name))
+ return false;
+ }
// The GNU linker strips .gnu_debuglink sections, so we do too.
// This is a feature used to keep debugging information in
// separate files.
return NULL;
}
+// When we put a .ctors or .dtors section with more than one word into
+// a .init_array or .fini_array section, we need to reverse the words
+// in the .ctors/.dtors section. This is because .init_array executes
+// constructors front to back, where .ctors executes them back to
+// front, and vice-versa for .fini_array/.dtors. Although we do want
+// to remap .ctors/.dtors into .init_array/.fini_array because it can
+// be more efficient, we don't want to change the order in which
+// constructors/destructors are run. This set just keeps track of
+// these sections which need to be reversed. It is only changed by
+// Layout::layout. It should be a private member of Layout, but that
+// would require layout.h to #include object.h to get the definition
+// of Section_id.
+static Unordered_set<Section_id, Section_id_hash> ctors_sections_in_init_array;
+
+// Return whether OBJECT/SHNDX is a .ctors/.dtors section mapped to a
+// .init_array/.fini_array section.
+
+bool
+Layout::is_ctors_in_init_array(Relobj* relobj, unsigned int shndx) const
+{
+ return (ctors_sections_in_init_array.find(Section_id(relobj, shndx))
+ != ctors_sections_in_init_array.end());
+}
+
// Return the output section to use for section NAME with type TYPE
// and section flags FLAGS. NAME must be canonicalized in the string
-// pool, and NAME_KEY is the key. IS_INTERP is true if this is the
-// .interp section. IS_DYNAMIC_LINKER_SECTION is true if this section
-// is used by the dynamic linker. IS_RELRO is true for a relro
-// section. IS_LAST_RELRO is true for the last relro section.
-// IS_FIRST_NON_RELRO is true for the first non-relro section.
+// pool, and NAME_KEY is the key. ORDER is where this should appear
+// in the output sections. IS_RELRO is true for a relro section.
Output_section*
Layout::get_output_section(const char* name, Stringpool::Key name_key,
elfcpp::Elf_Word type, elfcpp::Elf_Xword flags,
Output_section_order order, bool is_relro)
{
+ elfcpp::Elf_Word lookup_type = type;
+
+ // For lookup purposes, treat INIT_ARRAY, FINI_ARRAY, and
+ // PREINIT_ARRAY like PROGBITS. This ensures that we combine
+ // .init_array, .fini_array, and .preinit_array sections by name
+ // whatever their type in the input file. We do this because the
+ // types are not always right in the input files.
+ if (lookup_type == elfcpp::SHT_INIT_ARRAY
+ || lookup_type == elfcpp::SHT_FINI_ARRAY
+ || lookup_type == elfcpp::SHT_PREINIT_ARRAY)
+ lookup_type = elfcpp::SHT_PROGBITS;
+
elfcpp::Elf_Xword lookup_flags = flags;
// Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
// controlling this.
lookup_flags &= ~(elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR);
- const Key key(name_key, std::make_pair(type, lookup_flags));
+ const Key key(name_key, std::make_pair(lookup_type, lookup_flags));
const std::pair<Key, Output_section*> v(key, NULL);
std::pair<Section_name_map::iterator, bool> ins(
this->section_name_map_.insert(v));
// there should be an option to control this.
Output_section* os = NULL;
- if (type == elfcpp::SHT_PROGBITS)
+ if (lookup_type == elfcpp::SHT_PROGBITS)
{
- if (flags == 0)
- {
- Output_section* same_name = this->find_output_section(name);
- if (same_name != NULL
- && same_name->type() == elfcpp::SHT_PROGBITS
- && (same_name->flags() & elfcpp::SHF_TLS) == 0)
- os = same_name;
- }
- else if ((flags & elfcpp::SHF_TLS) == 0)
- {
- elfcpp::Elf_Xword zero_flags = 0;
- const Key zero_key(name_key, std::make_pair(type, zero_flags));
- Section_name_map::iterator p =
- this->section_name_map_.find(zero_key);
- if (p != this->section_name_map_.end())
+ if (flags == 0)
+ {
+ Output_section* same_name = this->find_output_section(name);
+ if (same_name != NULL
+ && (same_name->type() == elfcpp::SHT_PROGBITS
+ || same_name->type() == elfcpp::SHT_INIT_ARRAY
+ || same_name->type() == elfcpp::SHT_FINI_ARRAY
+ || same_name->type() == elfcpp::SHT_PREINIT_ARRAY)
+ && (same_name->flags() & elfcpp::SHF_TLS) == 0)
+ os = same_name;
+ }
+ else if ((flags & elfcpp::SHF_TLS) == 0)
+ {
+ elfcpp::Elf_Xword zero_flags = 0;
+ const Key zero_key(name_key, std::make_pair(lookup_type,
+ zero_flags));
+ Section_name_map::iterator p =
+ this->section_name_map_.find(zero_key);
+ if (p != this->section_name_map_.end())
os = p->second;
- }
+ }
}
if (os == NULL)
}
}
+// Returns TRUE iff NAME (an input section from RELOBJ) will
+// be mapped to an output section that should be KEPT.
+
+bool
+Layout::keep_input_section(const Relobj* relobj, const char* name)
+{
+ if (! this->script_options_->saw_sections_clause())
+ return false;
+
+ Script_sections* ss = this->script_options_->script_sections();
+ const char* file_name = relobj == NULL ? NULL : relobj->name().c_str();
+ Output_section** output_section_slot;
+ Script_sections::Section_type script_section_type;
+ bool keep;
+
+ name = ss->output_section_name(file_name, name, &output_section_slot,
+ &script_section_type, &keep);
+ return name != NULL && keep;
+}
+
+// Clear the input section flags that should not be copied to the
+// output section.
+
+elfcpp::Elf_Xword
+Layout::get_output_section_flags(elfcpp::Elf_Xword input_section_flags)
+{
+ // Some flags in the input section should not be automatically
+ // copied to the output section.
+ input_section_flags &= ~ (elfcpp::SHF_INFO_LINK
+ | elfcpp::SHF_GROUP
+ | elfcpp::SHF_MERGE
+ | elfcpp::SHF_STRINGS);
+
+ // We only clear the SHF_LINK_ORDER flag in for
+ // a non-relocatable link.
+ if (!parameters->options().relocatable())
+ input_section_flags &= ~elfcpp::SHF_LINK_ORDER;
+
+ return input_section_flags;
+}
+
// Pick the output section to use for section NAME, in input file
// RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
// linker created section. IS_INPUT_SECTION is true if we are
// choosing an output section for an input section found in a input
-// file. IS_INTERP is true if this is the .interp section.
-// IS_DYNAMIC_LINKER_SECTION is true if this section is used by the
-// dynamic linker. IS_RELRO is true for a relro section.
-// IS_LAST_RELRO is true for the last relro section.
-// IS_FIRST_NON_RELRO is true for the first non-relro section. This
-// will return NULL if the input section should be discarded.
+// file. ORDER is where this section should appear in the output
+// sections. IS_RELRO is true for a relro section. This will return
+// NULL if the input section should be discarded.
Output_section*
Layout::choose_output_section(const Relobj* relobj, const char* name,
// sections to segments.
gold_assert(!is_input_section || !this->sections_are_attached_);
- // Some flags in the input section should not be automatically
- // copied to the output section.
- flags &= ~ (elfcpp::SHF_INFO_LINK
- | elfcpp::SHF_GROUP
- | elfcpp::SHF_MERGE
- | elfcpp::SHF_STRINGS);
-
- // We only clear the SHF_LINK_ORDER flag in for
- // a non-relocatable link.
- if (!parameters->options().relocatable())
- flags &= ~elfcpp::SHF_LINK_ORDER;
+ flags = this->get_output_section_flags(flags);
if (this->script_options_->saw_sections_clause())
{
Output_section** output_section_slot;
Script_sections::Section_type script_section_type;
const char* orig_name = name;
+ bool keep;
name = ss->output_section_name(file_name, name, &output_section_slot,
- &script_section_type);
+ &script_section_type, &keep);
+
if (name == NULL)
{
gold_debug(DEBUG_SCRIPT, _("Unable to create output section '%s' "
if (is_input_section
&& !this->script_options_->saw_sections_clause()
&& !parameters->options().relocatable())
- name = Layout::output_section_name(name, &len);
+ {
+ const char *orig_name = name;
+ name = parameters->target().output_section_name(relobj, name, &len);
+ if (name == NULL)
+ name = Layout::output_section_name(relobj, orig_name, &len);
+ }
Stringpool::Key name_key;
name = this->namepool_.add_with_length(name, len, true, &name_key);
{
unsigned int sh_type = shdr.get_sh_type();
- // We preserve the layout of PROGBITS, NOBITS, and NOTE sections.
+ // We preserve the layout of PROGBITS, NOBITS, INIT_ARRAY, FINI_ARRAY,
+ // PRE_INIT_ARRAY, and NOTE sections.
// All others will be created from scratch and reallocated.
- if (sh_type != elfcpp::SHT_PROGBITS
- && sh_type != elfcpp::SHT_NOBITS
- && sh_type != elfcpp::SHT_NOTE)
+ if (!can_incremental_update(sh_type))
+ return NULL;
+
+ // If we're generating a .gdb_index section, we need to regenerate
+ // it from scratch.
+ if (parameters->options().gdb_index()
+ && sh_type == elfcpp::SHT_PROGBITS
+ && strcmp(name, ".gdb_index") == 0)
return NULL;
typename elfcpp::Elf_types<size>::Elf_Addr sh_addr = shdr.get_sh_addr();
Stringpool::Key name_key;
name = this->namepool_.add(name, true, &name_key);
Output_section* os = this->get_output_section(name, name_key, sh_type,
- sh_flags, ORDER_INVALID, false);
+ sh_flags, ORDER_INVALID, false);
os->set_fixed_layout(sh_addr, sh_offset, sh_size, sh_addralign);
if (sh_type != elfcpp::SHT_NOBITS)
this->free_list_.remove(sh_offset, sh_offset + sh_size);
return os;
}
+// Return the index by which an input section should be ordered. This
+// is used to sort some .text sections, for compatibility with GNU ld.
+
+int
+Layout::special_ordering_of_input_section(const char* name)
+{
+ // The GNU linker has some special handling for some sections that
+ // wind up in the .text section. Sections that start with these
+ // prefixes must appear first, and must appear in the order listed
+ // here.
+ static const char* const text_section_sort[] =
+ {
+ ".text.unlikely",
+ ".text.exit",
+ ".text.startup",
+ ".text.hot"
+ };
+
+ for (size_t i = 0;
+ i < sizeof(text_section_sort) / sizeof(text_section_sort[0]);
+ i++)
+ if (is_prefix_of(text_section_sort[i], name))
+ return i;
+
+ return -1;
+}
+
// Return the output section to use for input section SHNDX, with name
// NAME, with header HEADER, from object OBJECT. RELOC_SHNDX is the
// index of a relocation section which applies to this section, or 0
if (!this->include_section(object, name, shdr))
return NULL;
- Output_section* os;
-
- // Sometimes .init_array*, .preinit_array* and .fini_array* do not have
- // correct section types. Force them here.
elfcpp::Elf_Word sh_type = shdr.get_sh_type();
- if (sh_type == elfcpp::SHT_PROGBITS)
- {
- static const char init_array_prefix[] = ".init_array";
- static const char preinit_array_prefix[] = ".preinit_array";
- static const char fini_array_prefix[] = ".fini_array";
- static size_t init_array_prefix_size = sizeof(init_array_prefix) - 1;
- static size_t preinit_array_prefix_size =
- sizeof(preinit_array_prefix) - 1;
- static size_t fini_array_prefix_size = sizeof(fini_array_prefix) - 1;
-
- if (strncmp(name, init_array_prefix, init_array_prefix_size) == 0)
- sh_type = elfcpp::SHT_INIT_ARRAY;
- else if (strncmp(name, preinit_array_prefix, preinit_array_prefix_size)
- == 0)
- sh_type = elfcpp::SHT_PREINIT_ARRAY;
- else if (strncmp(name, fini_array_prefix, fini_array_prefix_size) == 0)
- sh_type = elfcpp::SHT_FINI_ARRAY;
- }
// In a relocatable link a grouped section must not be combined with
// any other sections.
+ Output_section* os;
if (parameters->options().relocatable()
&& (shdr.get_sh_flags() & elfcpp::SHF_GROUP) != 0)
{
}
else
{
- os = this->choose_output_section(object, name, sh_type,
- shdr.get_sh_flags(), true,
- ORDER_INVALID, false);
+ // Plugins can choose to place one or more subsets of sections in
+ // unique segments and this is done by mapping these section subsets
+ // to unique output sections. Check if this section needs to be
+ // remapped to a unique output section.
+ Section_segment_map::iterator it
+ = this->section_segment_map_.find(Const_section_id(object, shndx));
+ if (it == this->section_segment_map_.end())
+ {
+ os = this->choose_output_section(object, name, sh_type,
+ shdr.get_sh_flags(), true,
+ ORDER_INVALID, false);
+ }
+ else
+ {
+ // We know the name of the output section, directly call
+ // get_output_section here by-passing choose_output_section.
+ elfcpp::Elf_Xword flags
+ = this->get_output_section_flags(shdr.get_sh_flags());
+
+ const char* os_name = it->second->name;
+ Stringpool::Key name_key;
+ os_name = this->namepool_.add(os_name, true, &name_key);
+ os = this->get_output_section(os_name, name_key, sh_type, flags,
+ ORDER_INVALID, false);
+ if (!os->is_unique_segment())
+ {
+ os->set_is_unique_segment();
+ os->set_extra_segment_flags(it->second->flags);
+ os->set_segment_alignment(it->second->align);
+ }
+ }
if (os == NULL)
return NULL;
}
// By default the GNU linker sorts input sections whose names match
- // .ctor.*, .dtor.*, .init_array.*, or .fini_array.*. The sections
- // are sorted by name. This is used to implement constructor
- // priority ordering. We are compatible.
+ // .ctors.*, .dtors.*, .init_array.*, or .fini_array.*. The
+ // sections are sorted by name. This is used to implement
+ // constructor priority ordering. We are compatible. When we put
+ // .ctor sections in .init_array and .dtor sections in .fini_array,
+ // we must also sort plain .ctor and .dtor sections.
if (!this->script_options_->saw_sections_clause()
+ && !parameters->options().relocatable()
&& (is_prefix_of(".ctors.", name)
|| is_prefix_of(".dtors.", name)
|| is_prefix_of(".init_array.", name)
- || is_prefix_of(".fini_array.", name)))
+ || is_prefix_of(".fini_array.", name)
+ || (parameters->options().ctors_in_init_array()
+ && (strcmp(name, ".ctors") == 0
+ || strcmp(name, ".dtors") == 0))))
+ os->set_must_sort_attached_input_sections();
+
+ // By default the GNU linker sorts some special text sections ahead
+ // of others. We are compatible.
+ if (parameters->options().text_reorder()
+ && !this->script_options_->saw_sections_clause()
+ && !this->is_section_ordering_specified()
+ && !parameters->options().relocatable()
+ && Layout::special_ordering_of_input_section(name) >= 0)
os->set_must_sort_attached_input_sections();
+ // If this is a .ctors or .ctors.* section being mapped to a
+ // .init_array section, or a .dtors or .dtors.* section being mapped
+ // to a .fini_array section, we will need to reverse the words if
+ // there is more than one. Record this section for later. See
+ // ctors_sections_in_init_array above.
+ if (!this->script_options_->saw_sections_clause()
+ && !parameters->options().relocatable()
+ && shdr.get_sh_size() > size / 8
+ && (((strcmp(name, ".ctors") == 0
+ || is_prefix_of(".ctors.", name))
+ && strcmp(os->name(), ".init_array") == 0)
+ || ((strcmp(name, ".dtors") == 0
+ || is_prefix_of(".dtors.", name))
+ && strcmp(os->name(), ".fini_array") == 0)))
+ ctors_sections_in_init_array.insert(Section_id(object, shndx));
+
// FIXME: Handle SHF_LINK_ORDER somewhere.
elfcpp::Elf_Xword orig_flags = os->flags();
return os;
}
+// Maps section SECN to SEGMENT s.
+void
+Layout::insert_section_segment_map(Const_section_id secn,
+ Unique_segment_info *s)
+{
+ gold_assert(this->unique_segment_for_sections_specified_);
+ this->section_segment_map_[secn] = s;
+}
+
// Handle a relocation section when doing a relocatable link.
template<int size, bool big_endian>
unsigned int reloc_shndx, unsigned int reloc_type,
off_t* off)
{
- gold_assert(shdr.get_sh_type() == elfcpp::SHT_PROGBITS);
+ gold_assert(shdr.get_sh_type() == elfcpp::SHT_PROGBITS
+ || shdr.get_sh_type() == elfcpp::SHT_X86_64_UNWIND);
gold_assert((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
- const char* const name = ".eh_frame";
- Output_section* os = this->choose_output_section(object, name,
+ Output_section* os = this->make_eh_frame_section(object);
+ if (os == NULL)
+ return NULL;
+
+ gold_assert(this->eh_frame_section_ == os);
+
+ elfcpp::Elf_Xword orig_flags = os->flags();
+
+ if (!parameters->incremental()
+ && this->eh_frame_data_->add_ehframe_input_section(object,
+ symbols,
+ symbols_size,
+ symbol_names,
+ symbol_names_size,
+ shndx,
+ reloc_shndx,
+ reloc_type))
+ {
+ os->update_flags_for_input_section(shdr.get_sh_flags());
+
+ // A writable .eh_frame section is a RELRO section.
+ if ((orig_flags & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR))
+ != (os->flags() & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR)))
+ {
+ os->set_is_relro();
+ os->set_order(ORDER_RELRO);
+ }
+
+ // We found a .eh_frame section we are going to optimize, so now
+ // we can add the set of optimized sections to the output
+ // section. We need to postpone adding this until we've found a
+ // section we can optimize so that the .eh_frame section in
+ // crtbegin.o winds up at the start of the output section.
+ if (!this->added_eh_frame_data_)
+ {
+ os->add_output_section_data(this->eh_frame_data_);
+ this->added_eh_frame_data_ = true;
+ }
+ *off = -1;
+ }
+ else
+ {
+ // We couldn't handle this .eh_frame section for some reason.
+ // Add it as a normal section.
+ bool saw_sections_clause = this->script_options_->saw_sections_clause();
+ *off = os->add_input_section(this, object, shndx, ".eh_frame", shdr,
+ reloc_shndx, saw_sections_clause);
+ this->have_added_input_section_ = true;
+
+ if ((orig_flags & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR))
+ != (os->flags() & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR)))
+ os->set_order(this->default_section_order(os, false));
+ }
+
+ return os;
+}
+
+// Create and return the magic .eh_frame section. Create
+// .eh_frame_hdr also if appropriate. OBJECT is the object with the
+// input .eh_frame section; it may be NULL.
+
+Output_section*
+Layout::make_eh_frame_section(const Relobj* object)
+{
+ // FIXME: On x86_64, this could use SHT_X86_64_UNWIND rather than
+ // SHT_PROGBITS.
+ Output_section* os = this->choose_output_section(object, ".eh_frame",
elfcpp::SHT_PROGBITS,
elfcpp::SHF_ALLOC, false,
ORDER_EHFRAME, false);
}
}
- gold_assert(this->eh_frame_section_ == os);
+ return os;
+}
- if (!parameters->incremental()
- && this->eh_frame_data_->add_ehframe_input_section(object,
- symbols,
- symbols_size,
- symbol_names,
- symbol_names_size,
- shndx,
- reloc_shndx,
- reloc_type))
+// Add an exception frame for a PLT. This is called from target code.
+
+void
+Layout::add_eh_frame_for_plt(Output_data* plt, const unsigned char* cie_data,
+ size_t cie_length, const unsigned char* fde_data,
+ size_t fde_length)
+{
+ if (parameters->incremental())
{
- os->update_flags_for_input_section(shdr.get_sh_flags());
+ // FIXME: Maybe this could work some day....
+ return;
+ }
+ Output_section* os = this->make_eh_frame_section(NULL);
+ if (os == NULL)
+ return;
+ this->eh_frame_data_->add_ehframe_for_plt(plt, cie_data, cie_length,
+ fde_data, fde_length);
+ if (!this->added_eh_frame_data_)
+ {
+ os->add_output_section_data(this->eh_frame_data_);
+ this->added_eh_frame_data_ = true;
+ }
+}
- // A writable .eh_frame section is a RELRO section.
- if ((shdr.get_sh_flags() & elfcpp::SHF_WRITE) != 0)
- os->set_is_relro();
+// Scan a .debug_info or .debug_types section, and add summary
+// information to the .gdb_index section.
- // We found a .eh_frame section we are going to optimize, so now
- // we can add the set of optimized sections to the output
- // section. We need to postpone adding this until we've found a
- // section we can optimize so that the .eh_frame section in
- // crtbegin.o winds up at the start of the output section.
- if (!this->added_eh_frame_data_)
- {
- os->add_output_section_data(this->eh_frame_data_);
- this->added_eh_frame_data_ = true;
- }
- *off = -1;
- }
- else
+template<int size, bool big_endian>
+void
+Layout::add_to_gdb_index(bool is_type_unit,
+ Sized_relobj<size, big_endian>* object,
+ const unsigned char* symbols,
+ off_t symbols_size,
+ unsigned int shndx,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type)
+{
+ if (this->gdb_index_data_ == NULL)
{
- // We couldn't handle this .eh_frame section for some reason.
- // Add it as a normal section.
- bool saw_sections_clause = this->script_options_->saw_sections_clause();
- *off = os->add_input_section(this, object, shndx, name, shdr, reloc_shndx,
- saw_sections_clause);
- this->have_added_input_section_ = true;
+ Output_section* os = this->choose_output_section(NULL, ".gdb_index",
+ elfcpp::SHT_PROGBITS, 0,
+ false, ORDER_INVALID,
+ false);
+ if (os == NULL)
+ return;
+
+ this->gdb_index_data_ = new Gdb_index(os);
+ os->add_output_section_data(this->gdb_index_data_);
+ os->set_after_input_sections();
}
- return os;
+ this->gdb_index_data_->scan_debug_info(is_type_unit, object, symbols,
+ symbols_size, shndx, reloc_shndx,
+ reloc_type);
}
// Add POSD to an output section using NAME, TYPE, and FLAGS. Return
os = new Output_compressed_section(¶meters->options(), name, type,
flags);
else if ((flags & elfcpp::SHF_ALLOC) == 0
- && parameters->options().strip_debug_non_line()
- && strcmp(".debug_abbrev", name) == 0)
+ && parameters->options().strip_debug_non_line()
+ && strcmp(".debug_abbrev", name) == 0)
{
os = this->debug_abbrev_ = new Output_reduced_debug_abbrev_section(
- name, type, flags);
+ name, type, flags);
if (this->debug_info_)
- this->debug_info_->set_abbreviations(this->debug_abbrev_);
+ this->debug_info_->set_abbreviations(this->debug_abbrev_);
}
else if ((flags & elfcpp::SHF_ALLOC) == 0
- && parameters->options().strip_debug_non_line()
- && strcmp(".debug_info", name) == 0)
+ && parameters->options().strip_debug_non_line()
+ && strcmp(".debug_info", name) == 0)
{
os = this->debug_info_ = new Output_reduced_debug_info_section(
- name, type, flags);
+ name, type, flags);
if (this->debug_abbrev_)
- this->debug_info_->set_abbreviations(this->debug_abbrev_);
+ this->debug_info_->set_abbreviations(this->debug_abbrev_);
}
else
{
+ // Sometimes .init_array*, .preinit_array* and .fini_array* do
+ // not have correct section types. Force them here.
+ if (type == elfcpp::SHT_PROGBITS)
+ {
+ if (is_prefix_of(".init_array", name))
+ type = elfcpp::SHT_INIT_ARRAY;
+ else if (is_prefix_of(".preinit_array", name))
+ type = elfcpp::SHT_PREINIT_ARRAY;
+ else if (is_prefix_of(".fini_array", name))
+ type = elfcpp::SHT_FINI_ARRAY;
+ }
+
// FIXME: const_cast is ugly.
Target* target = const_cast<Target*>(¶meters->target());
os = target->make_output_section(name, type, flags);
bool is_relro_local = false;
if (!this->script_options_->saw_sections_clause()
&& parameters->options().relro()
- && type == elfcpp::SHT_PROGBITS
&& (flags & elfcpp::SHF_ALLOC) != 0
&& (flags & elfcpp::SHF_WRITE) != 0)
{
- if (strcmp(name, ".data.rel.ro") == 0)
- is_relro = true;
- else if (strcmp(name, ".data.rel.ro.local") == 0)
+ if (type == elfcpp::SHT_PROGBITS)
{
- is_relro = true;
- is_relro_local = true;
+ if ((flags & elfcpp::SHF_TLS) != 0)
+ is_relro = true;
+ else if (strcmp(name, ".data.rel.ro") == 0)
+ is_relro = true;
+ else if (strcmp(name, ".data.rel.ro.local") == 0)
+ {
+ is_relro = true;
+ is_relro_local = true;
+ }
+ else if (strcmp(name, ".ctors") == 0
+ || strcmp(name, ".dtors") == 0
+ || strcmp(name, ".jcr") == 0)
+ is_relro = true;
}
else if (type == elfcpp::SHT_INIT_ARRAY
|| type == elfcpp::SHT_FINI_ARRAY
|| type == elfcpp::SHT_PREINIT_ARRAY)
is_relro = true;
- else if (strcmp(name, ".ctors") == 0
- || strcmp(name, ".dtors") == 0
- || strcmp(name, ".jcr") == 0)
- is_relro = true;
}
if (is_relro)
// do the same. We need to know that this might happen before we
// attach any input sections.
if (!this->script_options_->saw_sections_clause()
- && (strcmp(name, ".ctors") == 0
- || strcmp(name, ".dtors") == 0
- || strcmp(name, ".init_array") == 0
- || strcmp(name, ".fini_array") == 0))
+ && !parameters->options().relocatable()
+ && (strcmp(name, ".init_array") == 0
+ || strcmp(name, ".fini_array") == 0
+ || (!parameters->options().ctors_in_init_array()
+ && (strcmp(name, ".ctors") == 0
+ || strcmp(name, ".dtors") == 0))))
os->set_may_sort_attached_input_sections();
+ // The GNU linker by default sorts .text.{unlikely,exit,startup,hot}
+ // sections before other .text sections. We are compatible. We
+ // need to know that this might happen before we attach any input
+ // sections.
+ if (parameters->options().text_reorder()
+ && !this->script_options_->saw_sections_clause()
+ && !this->is_section_ordering_specified()
+ && !parameters->options().relocatable()
+ && strcmp(name, ".text") == 0)
+ os->set_may_sort_attached_input_sections();
+
+ // GNU linker sorts section by name with --sort-section=name.
+ if (strcmp(parameters->options().sort_section(), "name") == 0)
+ os->set_must_sort_attached_input_sections();
+
// Check for .stab*str sections, as .stab* sections need to link to
// them.
if (type == elfcpp::SHT_STRTAB
&& strcmp(name + strlen(name) - 3, "str") == 0)
this->have_stabstr_section_ = true;
+ // During a full incremental link, we add patch space to most
+ // PROGBITS and NOBITS sections. Flag those that may be
+ // arbitrarily padded.
+ if ((type == elfcpp::SHT_PROGBITS || type == elfcpp::SHT_NOBITS)
+ && order != ORDER_INTERP
+ && order != ORDER_INIT
+ && order != ORDER_PLT
+ && order != ORDER_FINI
+ && order != ORDER_RELRO_LAST
+ && order != ORDER_NON_RELRO_FIRST
+ && strcmp(name, ".eh_frame") != 0
+ && strcmp(name, ".ctors") != 0
+ && strcmp(name, ".dtors") != 0
+ && strcmp(name, ".jcr") != 0)
+ {
+ os->set_is_patch_space_allowed();
+
+ // Certain sections require "holes" to be filled with
+ // specific fill patterns. These fill patterns may have
+ // a minimum size, so we must prevent allocations from the
+ // free list that leave a hole smaller than the minimum.
+ if (strcmp(name, ".debug_info") == 0)
+ os->set_free_space_fill(new Output_fill_debug_info(false));
+ else if (strcmp(name, ".debug_types") == 0)
+ os->set_free_space_fill(new Output_fill_debug_info(true));
+ else if (strcmp(name, ".debug_line") == 0)
+ os->set_free_space_fill(new Output_fill_debug_line());
+ }
+
// If we have already attached the sections to segments, then we
// need to attach this one now. This happens for sections created
// directly by the linker.
if (this->sections_are_attached_)
- this->attach_section_to_segment(os);
+ this->attach_section_to_segment(¶meters->target(), os);
return os;
}
// seen all the input sections.
void
-Layout::attach_sections_to_segments()
+Layout::attach_sections_to_segments(const Target* target)
{
for (Section_list::iterator p = this->section_list_.begin();
p != this->section_list_.end();
++p)
- this->attach_section_to_segment(*p);
+ this->attach_section_to_segment(target, *p);
this->sections_are_attached_ = true;
}
// Attach an output section to a segment.
void
-Layout::attach_section_to_segment(Output_section* os)
+Layout::attach_section_to_segment(const Target* target, Output_section* os)
{
if ((os->flags() & elfcpp::SHF_ALLOC) == 0)
this->unattached_section_list_.push_back(os);
else
- this->attach_allocated_section_to_segment(os);
+ this->attach_allocated_section_to_segment(target, os);
}
// Attach an allocated output section to a segment.
void
-Layout::attach_allocated_section_to_segment(Output_section* os)
+Layout::attach_allocated_section_to_segment(const Target* target,
+ Output_section* os)
{
elfcpp::Elf_Xword flags = os->flags();
gold_assert((flags & elfcpp::SHF_ALLOC) != 0);
elfcpp::Elf_Word seg_flags = Layout::section_flags_to_segment(flags);
+ // If this output section's segment has extra flags that need to be set,
+ // coming from a linker plugin, do that.
+ seg_flags |= os->extra_segment_flags();
+
// Check for --section-start.
uint64_t addr;
bool is_address_set = parameters->options().section_start(os->name(), &addr);
// have to use a linker script.
Segment_list::const_iterator p;
- for (p = this->segment_list_.begin();
- p != this->segment_list_.end();
- ++p)
+ if (!os->is_unique_segment())
{
- if ((*p)->type() != elfcpp::PT_LOAD)
- continue;
- if (!parameters->options().omagic()
- && ((*p)->flags() & elfcpp::PF_W) != (seg_flags & elfcpp::PF_W))
- continue;
- if (parameters->options().rosegment()
- && ((*p)->flags() & elfcpp::PF_X) != (seg_flags & elfcpp::PF_X))
- continue;
- // If -Tbss was specified, we need to separate the data and BSS
- // segments.
- if (parameters->options().user_set_Tbss())
+ for (p = this->segment_list_.begin();
+ p != this->segment_list_.end();
+ ++p)
{
- if ((os->type() == elfcpp::SHT_NOBITS)
- == (*p)->has_any_data_sections())
+ if ((*p)->type() != elfcpp::PT_LOAD)
continue;
- }
- if (os->is_large_data_section() && !(*p)->is_large_data_segment())
- continue;
-
- if (is_address_set)
- {
- if ((*p)->are_addresses_set())
+ if ((*p)->is_unique_segment())
+ continue;
+ if (!parameters->options().omagic()
+ && ((*p)->flags() & elfcpp::PF_W) != (seg_flags & elfcpp::PF_W))
+ continue;
+ if ((target->isolate_execinstr() || parameters->options().rosegment())
+ && ((*p)->flags() & elfcpp::PF_X) != (seg_flags & elfcpp::PF_X))
+ continue;
+ // If -Tbss was specified, we need to separate the data and BSS
+ // segments.
+ if (parameters->options().user_set_Tbss())
+ {
+ if ((os->type() == elfcpp::SHT_NOBITS)
+ == (*p)->has_any_data_sections())
+ continue;
+ }
+ if (os->is_large_data_section() && !(*p)->is_large_data_segment())
continue;
- (*p)->add_initial_output_data(os);
- (*p)->update_flags_for_output_section(seg_flags);
- (*p)->set_addresses(addr, addr);
- break;
- }
+ if (is_address_set)
+ {
+ if ((*p)->are_addresses_set())
+ continue;
- (*p)->add_output_section_to_load(this, os, seg_flags);
- break;
+ (*p)->add_initial_output_data(os);
+ (*p)->update_flags_for_output_section(seg_flags);
+ (*p)->set_addresses(addr, addr);
+ break;
+ }
+
+ (*p)->add_output_section_to_load(this, os, seg_flags);
+ break;
+ }
}
- if (p == this->segment_list_.end())
+ if (p == this->segment_list_.end()
+ || os->is_unique_segment())
{
Output_segment* oseg = this->make_output_segment(elfcpp::PT_LOAD,
- seg_flags);
+ seg_flags);
if (os->is_large_data_section())
oseg->set_is_large_data_segment();
oseg->add_output_section_to_load(this, os, seg_flags);
if (is_address_set)
oseg->set_addresses(addr, addr);
+ // Check if segment should be marked unique. For segments marked
+ // unique by linker plugins, set the new alignment if specified.
+ if (os->is_unique_segment())
+ {
+ oseg->set_is_unique_segment();
+ if (os->segment_alignment() != 0)
+ oseg->set_minimum_p_align(os->segment_alignment());
+ }
}
// If we see a loadable SHT_NOTE section, we create a PT_NOTE
{
// See if we already have an equivalent PT_NOTE segment.
for (p = this->segment_list_.begin();
- p != segment_list_.end();
- ++p)
- {
- if ((*p)->type() == elfcpp::PT_NOTE
- && (((*p)->flags() & elfcpp::PF_W)
- == (seg_flags & elfcpp::PF_W)))
- {
- (*p)->add_output_section_to_nonload(os, seg_flags);
- break;
- }
- }
+ p != segment_list_.end();
+ ++p)
+ {
+ if ((*p)->type() == elfcpp::PT_NOTE
+ && (((*p)->flags() & elfcpp::PF_W)
+ == (seg_flags & elfcpp::PF_W)))
+ {
+ (*p)->add_output_section_to_nonload(os, seg_flags);
+ break;
+ }
+ }
if (p == this->segment_list_.end())
- {
- Output_segment* oseg = this->make_output_segment(elfcpp::PT_NOTE,
- seg_flags);
- oseg->add_output_section_to_nonload(os, seg_flags);
- }
+ {
+ Output_segment* oseg = this->make_output_segment(elfcpp::PT_NOTE,
+ seg_flags);
+ oseg->add_output_section_to_nonload(os, seg_flags);
+ }
}
// If we see a loadable SHF_TLS section, we create a PT_TLS
this->make_output_segment(elfcpp::PT_GNU_RELRO, seg_flags);
this->relro_segment_->add_output_section_to_nonload(os, seg_flags);
}
+
+ // If we see a section named .interp, put it into a PT_INTERP
+ // segment. This seems broken to me, but this is what GNU ld does,
+ // and glibc expects it.
+ if (strcmp(os->name(), ".interp") == 0
+ && !this->script_options_->saw_phdrs_clause())
+ {
+ if (this->interp_segment_ == NULL)
+ this->make_output_segment(elfcpp::PT_INTERP, seg_flags);
+ else
+ gold_warning(_("multiple '.interp' sections in input files "
+ "may cause confusing PT_INTERP segment"));
+ this->interp_segment_->add_output_section_to_nonload(os, seg_flags);
+ }
}
// Make an output section for a script.
false, ORDER_RELRO,
true);
- this->dynamic_symbol_ =
- symtab->define_in_output_data("_DYNAMIC", NULL, Symbol_table::PREDEFINED,
- this->dynamic_section_, 0, 0,
- elfcpp::STT_OBJECT, elfcpp::STB_LOCAL,
- elfcpp::STV_HIDDEN, 0, false, false);
+ // A linker script may discard .dynamic, so check for NULL.
+ if (this->dynamic_section_ != NULL)
+ {
+ this->dynamic_symbol_ =
+ symtab->define_in_output_data("_DYNAMIC", NULL,
+ Symbol_table::PREDEFINED,
+ this->dynamic_section_, 0, 0,
+ elfcpp::STT_OBJECT, elfcpp::STB_LOCAL,
+ elfcpp::STV_HIDDEN, 0, false, false);
- this->dynamic_data_ = new Output_data_dynamic(&this->dynpool_);
+ this->dynamic_data_ = new Output_data_dynamic(&this->dynpool_);
- this->dynamic_section_->add_output_section_data(this->dynamic_data_);
+ this->dynamic_section_->add_output_section_data(this->dynamic_data_);
+ }
}
// For each output section whose name can be represented as C symbol,
{
const std::string name_string(name);
const std::string start_name(cident_section_start_prefix
- + name_string);
+ + name_string);
const std::string stop_name(cident_section_stop_prefix
- + name_string);
+ + name_string);
symtab->define_in_output_data(start_name.c_str(),
NULL, // version
// necessary.
Output_segment*
-Layout::find_first_load_seg()
+Layout::find_first_load_seg(const Target* target)
{
Output_segment* best = NULL;
for (Segment_list::const_iterator p = this->segment_list_.begin();
if ((*p)->type() == elfcpp::PT_LOAD
&& ((*p)->flags() & elfcpp::PF_R) != 0
&& (parameters->options().omagic()
- || ((*p)->flags() & elfcpp::PF_W) == 0))
- {
- if (best == NULL || this->segment_precedes(*p, best))
- best = *p;
- }
+ || ((*p)->flags() & elfcpp::PF_W) == 0)
+ && (!target->isolate_execinstr()
+ || ((*p)->flags() & elfcpp::PF_X) == 0))
+ {
+ if (best == NULL || this->segment_precedes(*p, best))
+ best = *p;
+ }
}
if (best != NULL)
return best;
this->relro_segment_ = segment;
++list_iter;
- }
+ }
else
{
- list_iter = this->segment_list_.erase(list_iter);
+ list_iter = this->segment_list_.erase(list_iter);
// This is a segment created during section layout. It should be
// safe to remove it since we should have removed all pointers to it.
delete segment;
(*p)->reset_address_and_file_offset();
}
-
+
// Reset special output object address and file offsets.
for (Data_list::iterator p = this->special_output_list_.begin();
p != this->special_output_list_.end();
p != this->script_output_section_data_list_.end();
++p)
delete *p;
- this->script_output_section_data_list_.clear();
+ this->script_output_section_data_list_.clear();
+
+ // Special-case fill output objects are recreated each time through
+ // the relaxation loop.
+ this->reset_relax_output();
+}
+
+void
+Layout::reset_relax_output()
+{
+ for (Data_list::const_iterator p = this->relax_output_list_.begin();
+ p != this->relax_output_list_.end();
+ ++p)
+ delete *p;
+ this->relax_output_list_.clear();
}
// Prepare for relaxation.
if (is_debugging_enabled(DEBUG_RELAXATION))
this->relaxation_debug_check_->check_output_data_for_reset_values(
- this->section_list_, this->special_output_list_);
+ this->section_list_, this->special_output_list_,
+ this->relax_output_list_);
// Also enable recording of output section data from scripts.
this->record_output_section_data_from_script_ = true;
}
+// If the user set the address of the text segment, that may not be
+// compatible with putting the segment headers and file headers into
+// that segment. For isolate_execinstr() targets, it's the rodata
+// segment rather than text where we might put the headers.
+static inline bool
+load_seg_unusable_for_headers(const Target* target)
+{
+ const General_options& options = parameters->options();
+ if (target->isolate_execinstr())
+ return (options.user_set_Trodata_segment()
+ && options.Trodata_segment() % target->abi_pagesize() != 0);
+ else
+ return (options.user_set_Ttext()
+ && options.Ttext() % target->abi_pagesize() != 0);
+}
+
// Relaxation loop body: If target has no relaxation, this runs only once
// Otherwise, the target relaxation hook is called at the end of
// each iteration. If the hook returns true, it means re-layout of
-// section is required.
+// section is required.
//
// The number of segments created by a linking script without a PHDRS
// clause may be affected by section sizes and alignments. There is
// layout. In order to be able to restart the section layout, we keep
// a copy of the segment list right before the relaxation loop and use
// that to restore the segments.
-//
-// PASS is the current relaxation pass number.
+//
+// PASS is the current relaxation pass number.
// SYMTAB is a symbol table.
// PLOAD_SEG is the address of a pointer for the load segment.
// PHDR_SEG is a pointer to the PHDR segment.
else if (parameters->options().relocatable())
load_seg = NULL;
else
- load_seg = this->find_first_load_seg();
+ load_seg = this->find_first_load_seg(target);
if (parameters->options().oformat_enum()
!= General_options::OBJECT_FORMAT_ELF)
load_seg = NULL;
- // If the user set the address of the text segment, that may not be
- // compatible with putting the segment headers and file headers into
- // that segment.
- if (parameters->options().user_set_Ttext())
- load_seg = NULL;
+ if (load_seg_unusable_for_headers(target))
+ {
+ load_seg = NULL;
+ phdr_seg = NULL;
+ }
gold_assert(phdr_seg == NULL
|| load_seg != NULL
load_seg->add_initial_output_data(z);
}
if (load_seg != NULL)
- load_seg->add_initial_output_data(segment_headers);
+ load_seg->add_initial_output_data(segment_headers);
if (phdr_seg != NULL)
- phdr_seg->add_initial_output_data(segment_headers);
+ phdr_seg->add_initial_output_data(segment_headers);
}
// Lay out the file header.
++it)
{
if (fnmatch((*it).c_str(), section_name.c_str(), FNM_NOESCAPE) == 0)
- {
- map_it = this->input_section_position_.find(*it);
- gold_assert(map_it != this->input_section_position_.end());
- return map_it->second;
- }
+ {
+ map_it = this->input_section_position_.find(*it);
+ gold_assert(map_it != this->input_section_position_.end());
+ return map_it->second;
+ }
}
return 0;
}
// Read the sequence of input sections from the file specified with
-// --section-ordering-file.
+// option --section-ordering-file.
void
Layout::read_layout_from_file()
in.open(filename);
if (!in)
gold_fatal(_("unable to open --section-ordering-file file %s: %s"),
- filename, strerror(errno));
+ filename, strerror(errno));
std::getline(in, line); // this chops off the trailing \n, if any
unsigned int position = 1;
+ this->set_section_ordering_specified();
while (in)
{
if (!line.empty() && line[line.length() - 1] == '\r') // Windows
- line.resize(line.length() - 1);
+ line.resize(line.length() - 1);
// Ignore comments, beginning with '#'
if (line[0] == '#')
- {
- std::getline(in, line);
- continue;
- }
+ {
+ std::getline(in, line);
+ continue;
+ }
this->input_section_position_[line] = position;
// Store all glob patterns in a vector.
if (is_wildcard_string(line.c_str()))
- this->input_section_glob_.push_back(line);
+ this->input_section_glob_.push_back(line);
position++;
std::getline(in, line);
}
std::vector<Symbol*> dynamic_symbols;
unsigned int local_dynamic_count;
Versions versions(*this->script_options()->version_script_info(),
- &this->dynpool_);
+ &this->dynpool_);
this->create_dynamic_symtab(input_objects, symtab, &dynstr,
&local_dynamic_count, &dynamic_symbols,
&versions);
// Create the .interp section to hold the name of the
- // interpreter, and put it in a PT_INTERP segment.
- if (!parameters->options().shared())
- this->create_interp(target);
+ // interpreter, and put it in a PT_INTERP segment. Don't do it
+ // if we saw a .interp section in an input file.
+ if ((!parameters->options().shared()
+ || parameters->options().dynamic_linker() != NULL)
+ && this->interp_segment_ == NULL)
+ this->create_interp(target);
// Finish the .dynamic section to hold the dynamic data, and put
// it in a PT_DYNAMIC segment.
// after we call create_version_sections.
this->set_dynamic_symbol_size(symtab);
}
-
+
// Create segment headers.
Output_segment_headers* segment_headers =
(parameters->options().relocatable()
: new Output_segment_headers(this->segment_list_));
// Lay out the file header.
- Output_file_header* file_header
- = new Output_file_header(target, symtab, segment_headers,
- parameters->options().entry());
+ Output_file_header* file_header = new Output_file_header(target, symtab,
+ segment_headers);
this->special_output_list_.push_back(file_header);
if (segment_headers != NULL)
// a linker script.
if (this->script_options_->saw_sections_clause())
this->place_orphan_sections_in_script();
-
+
Output_segment* load_seg;
off_t off;
unsigned int shndx;
// Take a snapshot of the section layout as needed.
if (target->may_relax())
this->prepare_for_relaxation();
-
+
// Run the relaxation loop to lay out sections.
do
{
while (target->may_relax()
&& target->relax(pass, input_objects, symtab, this, task));
+ // If there is a load segment that contains the file and program headers,
+ // provide a symbol __ehdr_start pointing there.
+ // A program can use this to examine itself robustly.
+ if (load_seg != NULL)
+ symtab->define_in_output_segment("__ehdr_start", NULL,
+ Symbol_table::PREDEFINED, load_seg, 0, 0,
+ elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
+ elfcpp::STV_HIDDEN, 0,
+ Symbol::SEGMENT_START, true);
+
// Set the file offsets of all the non-data sections we've seen so
// far which don't have to wait for the input sections. We need
// this in order to finalize local symbols in non-allocated
std::string desc;
if (strcmp(style, "md5") == 0)
descsz = 128 / 8;
- else if (strcmp(style, "sha1") == 0)
+ else if ((strcmp(style, "sha1") == 0) || (strcmp(style, "tree") == 0))
descsz = 160 / 8;
else if (strcmp(style, "uuid") == 0)
{
const char* incremental_strtab_name =
this->namepool_.add(".gnu_incremental_strtab", false, NULL);
Output_section* incremental_strtab_os = this->make_output_section(incremental_strtab_name,
- elfcpp::SHT_STRTAB, 0,
- ORDER_INVALID, false);
+ elfcpp::SHT_STRTAB, 0,
+ ORDER_INVALID, false);
Output_data_strtab* strtab_data =
new Output_data_strtab(incr->get_stringpool());
incremental_strtab_os->add_output_section_data(strtab_data);
// Return whether SEG1 should be before SEG2 in the output file. This
// is based entirely on the segment type and flags. When this is
-// called the segment addresses has normally not yet been set.
+// called the segment addresses have normally not yet been set.
bool
Layout::segment_precedes(const Output_segment* seg1,
// The order of non-PT_LOAD segments is unimportant. We simply sort
// by the numeric segment type and flags values. There should not
- // be more than one segment with the same type and flags.
+ // be more than one segment with the same type and flags, except
+ // when a linker script specifies such.
if (type1 != elfcpp::PT_LOAD)
{
if (type1 != type2)
return type1 < type2;
- gold_assert(flags1 != flags2);
+ gold_assert(flags1 != flags2
+ || this->script_options_->saw_phdrs_clause());
return flags1 < flags2;
}
return (flags1 & elfcpp::PF_R) == 0;
// We shouldn't get here--we shouldn't create segments which we
- // can't distinguish.
- gold_unreachable();
+ // can't distinguish. Unless of course we are using a weird linker
+ // script or overlapping --section-start options. We could also get
+ // here if plugins want unique segments for subsets of sections.
+ gold_assert(this->script_options_->saw_phdrs_clause()
+ || parameters->options().any_section_start()
+ || this->is_unique_segment_for_sections_specified());
+ return false;
}
// Increase OFF so that it is congruent to ADDR modulo ABI_PAGESIZE.
return aligned_off;
}
+// On targets where the text segment contains only executable code,
+// a non-executable segment is never the text segment.
+
+static inline bool
+is_text_segment(const Target* target, const Output_segment* seg)
+{
+ elfcpp::Elf_Xword flags = seg->flags();
+ if ((flags & elfcpp::PF_W) != 0)
+ return false;
+ if ((flags & elfcpp::PF_X) == 0)
+ return !target->isolate_execinstr();
+ return true;
+}
+
// Set the file offsets of all the segments, and all the sections they
// contain. They have all been created. LOAD_SEG must be be laid out
// first. Return the offset of the data to follow.
Layout::set_segment_offsets(const Target* target, Output_segment* load_seg,
unsigned int* pshndx)
{
- // Sort them into the final order.
- std::sort(this->segment_list_.begin(), this->segment_list_.end(),
- Layout::Compare_segments());
+ // Sort them into the final order. We use a stable sort so that we
+ // don't randomize the order of indistinguishable segments created
+ // by linker scripts.
+ std::stable_sort(this->segment_list_.begin(), this->segment_list_.end(),
+ Layout::Compare_segments(this));
// Find the PT_LOAD segments, and set their addresses and offsets
// and their section's addresses and offsets.
- uint64_t addr;
+ uint64_t start_addr;
if (parameters->options().user_set_Ttext())
- addr = parameters->options().Ttext();
+ start_addr = parameters->options().Ttext();
else if (parameters->options().output_is_position_independent())
- addr = 0;
+ start_addr = 0;
else
- addr = target->default_text_segment_address();
+ start_addr = target->default_text_segment_address();
+
+ uint64_t addr = start_addr;
off_t off = 0;
// If LOAD_SEG is NULL, then the file header and segment headers
const bool check_sections = parameters->options().check_sections();
Output_segment* last_load_segment = NULL;
+ unsigned int shndx_begin = *pshndx;
+ unsigned int shndx_load_seg = *pshndx;
+
for (Segment_list::iterator p = this->segment_list_.begin();
p != this->segment_list_.end();
++p)
{
if ((*p)->type() == elfcpp::PT_LOAD)
{
- if (load_seg != NULL && load_seg != *p)
- gold_unreachable();
- load_seg = NULL;
+ if (target->isolate_execinstr())
+ {
+ // When we hit the segment that should contain the
+ // file headers, reset the file offset so we place
+ // it and subsequent segments appropriately.
+ // We'll fix up the preceding segments below.
+ if (load_seg == *p)
+ {
+ if (off == 0)
+ load_seg = NULL;
+ else
+ {
+ off = 0;
+ shndx_load_seg = *pshndx;
+ }
+ }
+ }
+ else
+ {
+ // Verify that the file headers fall into the first segment.
+ if (load_seg != NULL && load_seg != *p)
+ gold_unreachable();
+ load_seg = NULL;
+ }
bool are_addresses_set = (*p)->are_addresses_set();
if (are_addresses_set)
// the physical address.
addr = (*p)->paddr();
}
+ else if (parameters->options().user_set_Ttext()
+ && (parameters->options().omagic()
+ || is_text_segment(target, *p)))
+ {
+ are_addresses_set = true;
+ }
+ else if (parameters->options().user_set_Trodata_segment()
+ && ((*p)->flags() & (elfcpp::PF_W | elfcpp::PF_X)) == 0)
+ {
+ addr = parameters->options().Trodata_segment();
+ are_addresses_set = true;
+ }
else if (parameters->options().user_set_Tdata()
&& ((*p)->flags() & elfcpp::PF_W) != 0
&& (!parameters->options().user_set_Tbss()
if (!parameters->options().nmagic()
&& !parameters->options().omagic())
- (*p)->set_minimum_p_align(common_pagesize);
+ (*p)->set_minimum_p_align(abi_pagesize);
if (!are_addresses_set)
{
addr = align_address(addr, (*p)->maximum_alignment());
aligned_addr = addr;
- if ((addr & (abi_pagesize - 1)) != 0)
- addr = addr + abi_pagesize;
+ if (load_seg == *p)
+ {
+ // This is the segment that will contain the file
+ // headers, so its offset will have to be exactly zero.
+ gold_assert(orig_off == 0);
+
+ // If the target wants a fixed minimum distance from the
+ // text segment to the read-only segment, move up now.
+ uint64_t min_addr =
+ start_addr + (parameters->options().user_set_rosegment_gap()
+ ? parameters->options().rosegment_gap()
+ : target->rosegment_gap());
+ if (addr < min_addr)
+ addr = min_addr;
+
+ // But this is not the first segment! To make its
+ // address congruent with its offset, that address better
+ // be aligned to the ABI-mandated page size.
+ addr = align_address(addr, abi_pagesize);
+ aligned_addr = addr;
+ }
+ else
+ {
+ if ((addr & (abi_pagesize - 1)) != 0)
+ addr = addr + abi_pagesize;
- off = orig_off + ((addr - orig_addr) & (abi_pagesize - 1));
+ off = orig_off + ((addr - orig_addr) & (abi_pagesize - 1));
+ }
}
if (!parameters->options().nmagic()
&& !parameters->options().omagic())
- off = align_file_offset(off, addr, abi_pagesize);
- else if (load_seg == NULL)
+ {
+ // Here we are also taking care of the case when
+ // the maximum segment alignment is larger than the page size.
+ off = align_file_offset(off, addr,
+ std::max(abi_pagesize,
+ (*p)->maximum_alignment()));
+ }
+ else
{
// This is -N or -n with a section script which prevents
// us from using a load segment. We need to ensure that
unsigned int shndx_hold = *pshndx;
bool has_relro = false;
- uint64_t new_addr = (*p)->set_section_addresses(this, false, addr,
+ uint64_t new_addr = (*p)->set_section_addresses(target, this,
+ false, addr,
&increase_relro,
&has_relro,
- &off, pshndx);
+ &off, pshndx);
// Now that we know the size of this segment, we may be able
// to save a page in memory, at the cost of wasting some
if (!are_addresses_set
&& !has_relro
&& aligned_addr != addr
- && !parameters->incremental_update())
+ && !parameters->incremental())
{
uint64_t first_off = (common_pagesize
- (aligned_addr
*pshndx = shndx_hold;
addr = align_address(aligned_addr, common_pagesize);
addr = align_address(addr, (*p)->maximum_alignment());
+ if ((addr & (abi_pagesize - 1)) != 0)
+ addr = addr + abi_pagesize;
off = orig_off + ((addr - orig_addr) & (abi_pagesize - 1));
off = align_file_offset(off, addr, abi_pagesize);
increase_relro = 0;
has_relro = false;
- new_addr = (*p)->set_section_addresses(this, true, addr,
+ new_addr = (*p)->set_section_addresses(target, this,
+ true, addr,
&increase_relro,
&has_relro,
- &off, pshndx);
+ &off, pshndx);
}
}
}
}
+ if (load_seg != NULL && target->isolate_execinstr())
+ {
+ // Process the early segments again, setting their file offsets
+ // so they land after the segments starting at LOAD_SEG.
+ off = align_file_offset(off, 0, target->abi_pagesize());
+
+ this->reset_relax_output();
+
+ for (Segment_list::iterator p = this->segment_list_.begin();
+ *p != load_seg;
+ ++p)
+ {
+ if ((*p)->type() == elfcpp::PT_LOAD)
+ {
+ // We repeat the whole job of assigning addresses and
+ // offsets, but we really only want to change the offsets and
+ // must ensure that the addresses all come out the same as
+ // they did the first time through.
+ bool has_relro = false;
+ const uint64_t old_addr = (*p)->vaddr();
+ const uint64_t old_end = old_addr + (*p)->memsz();
+ uint64_t new_addr = (*p)->set_section_addresses(target, this,
+ true, old_addr,
+ &increase_relro,
+ &has_relro,
+ &off,
+ &shndx_begin);
+ gold_assert(new_addr == old_end);
+ }
+ }
+
+ gold_assert(shndx_begin == shndx_load_seg);
+ }
+
// Handle the non-PT_LOAD segments, setting their offsets from their
// section's offsets.
for (Segment_list::iterator p = this->segment_list_.begin();
(*p)->set_address(0);
(*p)->set_file_offset(off);
(*p)->finalize_data_size();
- off += (*p)->data_size();
+ if ((*p)->type() != elfcpp::SHT_NOBITS)
+ off += (*p)->data_size();
(*p)->set_out_shndx(*pshndx);
++*pshndx;
}
if (pass == BEFORE_INPUT_SECTIONS_PASS
- && (*p)->after_input_sections())
- continue;
+ && (*p)->after_input_sections())
+ continue;
else if (pass == POSTPROCESSING_SECTIONS_PASS
- && (!(*p)->after_input_sections()
- || (*p)->type() == elfcpp::SHT_STRTAB))
- continue;
+ && (!(*p)->after_input_sections()
+ || (*p)->type() == elfcpp::SHT_STRTAB))
+ continue;
else if (pass == STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
- && (!(*p)->after_input_sections()
- || (*p)->type() != elfcpp::SHT_STRTAB))
- continue;
+ && (!(*p)->after_input_sections()
+ || (*p)->type() != elfcpp::SHT_STRTAB))
+ continue;
if (!parameters->incremental_update())
{
if (off == -1)
{
if (is_debugging_enabled(DEBUG_INCREMENTAL))
- this->free_list_.dump();
+ this->free_list_.dump();
gold_assert((*p)->output_section() != NULL);
- gold_fatal(_("out of patch space for section %s; "
- "relink with --incremental-full"),
- (*p)->output_section()->name());
+ gold_fallback(_("out of patch space for section %s; "
+ "relink with --incremental-full"),
+ (*p)->output_section()->name());
}
(*p)->set_file_offset(off);
(*p)->finalize_data_size();
if ((*p)->data_size() > current_size)
{
gold_assert((*p)->output_section() != NULL);
- gold_fatal(_("%s: section changed size; "
- "relink with --incremental-full"),
- (*p)->output_section()->name());
+ gold_fallback(_("%s: section changed size; "
+ "relink with --incremental-full"),
+ (*p)->output_section()->name());
}
gold_debug(DEBUG_INCREMENTAL,
"set_section_offsets: %08lx %08lx %s",
off += (*p)->data_size();
if (off > maxoff)
- maxoff = off;
+ maxoff = off;
// At this point the name must be set.
if (pass != STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS)
++p)
{
unsigned int index = (*p)->finalize_local_symbols(local_symbol_index,
- off, symtab);
+ off, symtab);
off += (index - local_symbol_index) * symsize;
local_symbol_index = index;
}
else
{
symtab_off = this->allocate(off, align, *poff);
- if (off == -1)
- gold_fatal(_("out of patch space for symbol table; "
- "relink with --incremental-full"));
+ if (off == -1)
+ gold_fallback(_("out of patch space for symbol table; "
+ "relink with --incremental-full"));
gold_debug(DEBUG_INCREMENTAL,
"create_symtab_sections: %08lx %08lx .symtab",
static_cast<long>(symtab_off),
oshdrs->pre_finalize_data_size();
off = this->allocate(oshdrs->data_size(), oshdrs->addralign(), *poff);
if (off == -1)
- gold_fatal(_("out of patch space for section header table; "
- "relink with --incremental-full"));
+ gold_fallback(_("out of patch space for section header table; "
+ "relink with --incremental-full"));
gold_debug(DEBUG_INCREMENTAL,
"create_shdrs: %08lx %08lx (section header table)",
static_cast<long>(off),
void
Layout::create_dynamic_symtab(const Input_objects* input_objects,
- Symbol_table* symtab,
+ Symbol_table* symtab,
Output_section** pdynstr,
unsigned int* plocal_dynamic_count,
std::vector<Symbol*>* pdynamic_symbols,
ORDER_DYNAMIC_LINKER,
false);
- Output_section_data* odata = new Output_data_fixed_space(index * symsize,
- align,
- "** dynsym");
- dynsym->add_output_section_data(odata);
+ // Check for NULL as a linker script may discard .dynsym.
+ if (dynsym != NULL)
+ {
+ Output_section_data* odata = new Output_data_fixed_space(index * symsize,
+ align,
+ "** dynsym");
+ dynsym->add_output_section_data(odata);
- dynsym->set_info(local_symcount);
- dynsym->set_entsize(symsize);
- dynsym->set_addralign(align);
+ dynsym->set_info(local_symcount);
+ dynsym->set_entsize(symsize);
+ dynsym->set_addralign(align);
- this->dynsym_section_ = dynsym;
+ this->dynsym_section_ = dynsym;
+ }
Output_data_dynamic* const odyn = this->dynamic_data_;
- odyn->add_section_address(elfcpp::DT_SYMTAB, dynsym);
- odyn->add_constant(elfcpp::DT_SYMENT, symsize);
+ if (odyn != NULL)
+ {
+ odyn->add_section_address(elfcpp::DT_SYMTAB, dynsym);
+ odyn->add_constant(elfcpp::DT_SYMENT, symsize);
+ }
// If there are more than SHN_LORESERVE allocated sections, we
// create a .dynsym_shndx section. It is possible that we don't
elfcpp::SHF_ALLOC,
false, ORDER_DYNAMIC_LINKER, false);
- this->dynsym_xindex_ = new Output_symtab_xindex(index);
+ if (dynsym_xindex != NULL)
+ {
+ this->dynsym_xindex_ = new Output_symtab_xindex(index);
- dynsym_xindex->add_output_section_data(this->dynsym_xindex_);
+ dynsym_xindex->add_output_section_data(this->dynsym_xindex_);
- dynsym_xindex->set_link_section(dynsym);
- dynsym_xindex->set_addralign(4);
- dynsym_xindex->set_entsize(4);
+ dynsym_xindex->set_link_section(dynsym);
+ dynsym_xindex->set_addralign(4);
+ dynsym_xindex->set_entsize(4);
- dynsym_xindex->set_after_input_sections();
+ dynsym_xindex->set_after_input_sections();
- // This tells the driver code to wait until the symbol table has
- // written out before writing out the postprocessing sections,
- // including the .dynsym_shndx section.
- this->any_postprocessing_sections_ = true;
+ // This tells the driver code to wait until the symbol table
+ // has written out before writing out the postprocessing
+ // sections, including the .dynsym_shndx section.
+ this->any_postprocessing_sections_ = true;
+ }
}
// Create the dynamic string table section.
false,
ORDER_DYNAMIC_LINKER,
false);
+ *pdynstr = dynstr;
+ if (dynstr != NULL)
+ {
+ Output_section_data* strdata = new Output_data_strtab(&this->dynpool_);
+ dynstr->add_output_section_data(strdata);
- Output_section_data* strdata = new Output_data_strtab(&this->dynpool_);
- dynstr->add_output_section_data(strdata);
-
- dynsym->set_link_section(dynstr);
- this->dynamic_section_->set_link_section(dynstr);
-
- odyn->add_section_address(elfcpp::DT_STRTAB, dynstr);
- odyn->add_section_size(elfcpp::DT_STRSZ, dynstr);
+ if (dynsym != NULL)
+ dynsym->set_link_section(dynstr);
+ if (this->dynamic_section_ != NULL)
+ this->dynamic_section_->set_link_section(dynstr);
- *pdynstr = dynstr;
+ if (odyn != NULL)
+ {
+ odyn->add_section_address(elfcpp::DT_STRTAB, dynstr);
+ odyn->add_section_size(elfcpp::DT_STRSZ, dynstr);
+ }
+ }
// Create the hash tables.
hashlen,
align,
"** hash");
- hashsec->add_output_section_data(hashdata);
+ if (hashsec != NULL && hashdata != NULL)
+ hashsec->add_output_section_data(hashdata);
- hashsec->set_link_section(dynsym);
- hashsec->set_entsize(4);
+ if (hashsec != NULL)
+ {
+ if (dynsym != NULL)
+ hashsec->set_link_section(dynsym);
+ hashsec->set_entsize(4);
+ }
- odyn->add_section_address(elfcpp::DT_HASH, hashsec);
+ if (odyn != NULL)
+ odyn->add_section_address(elfcpp::DT_HASH, hashsec);
}
if (strcmp(parameters->options().hash_style(), "gnu") == 0
hashlen,
align,
"** hash");
- hashsec->add_output_section_data(hashdata);
+ if (hashsec != NULL && hashdata != NULL)
+ hashsec->add_output_section_data(hashdata);
- hashsec->set_link_section(dynsym);
+ if (hashsec != NULL)
+ {
+ if (dynsym != NULL)
+ hashsec->set_link_section(dynsym);
- // For a 64-bit target, the entries in .gnu.hash do not have a
- // uniform size, so we only set the entry size for a 32-bit
- // target.
- if (parameters->target().get_size() == 32)
- hashsec->set_entsize(4);
+ // For a 64-bit target, the entries in .gnu.hash do not have
+ // a uniform size, so we only set the entry size for a
+ // 32-bit target.
+ if (parameters->target().get_size() == 32)
+ hashsec->set_entsize(4);
- odyn->add_section_address(elfcpp::DT_GNU_HASH, hashsec);
+ if (odyn != NULL)
+ odyn->add_section_address(elfcpp::DT_GNU_HASH, hashsec);
+ }
}
}
Layout::assign_local_dynsym_offsets(const Input_objects* input_objects)
{
Output_section* dynsym = this->dynsym_section_;
- gold_assert(dynsym != NULL);
+ if (dynsym == NULL)
+ return;
off_t off = dynsym->offset();
ORDER_DYNAMIC_LINKER,
false);
- unsigned char* vbuf;
- unsigned int vsize;
- versions->symbol_section_contents<size, big_endian>(symtab, &this->dynpool_,
- local_symcount,
- dynamic_symbols,
- &vbuf, &vsize);
-
- Output_section_data* vdata = new Output_data_const_buffer(vbuf, vsize, 2,
- "** versions");
-
- vsec->add_output_section_data(vdata);
- vsec->set_entsize(2);
- vsec->set_link_section(this->dynsym_section_);
+ // Check for NULL since a linker script may discard this section.
+ if (vsec != NULL)
+ {
+ unsigned char* vbuf;
+ unsigned int vsize;
+ versions->symbol_section_contents<size, big_endian>(symtab,
+ &this->dynpool_,
+ local_symcount,
+ dynamic_symbols,
+ &vbuf, &vsize);
+
+ Output_section_data* vdata = new Output_data_const_buffer(vbuf, vsize, 2,
+ "** versions");
+
+ vsec->add_output_section_data(vdata);
+ vsec->set_entsize(2);
+ vsec->set_link_section(this->dynsym_section_);
+ }
Output_data_dynamic* const odyn = this->dynamic_data_;
- odyn->add_section_address(elfcpp::DT_VERSYM, vsec);
+ if (odyn != NULL && vsec != NULL)
+ odyn->add_section_address(elfcpp::DT_VERSYM, vsec);
if (versions->any_defs())
{
Output_section* vdsec;
- vdsec= this->choose_output_section(NULL, ".gnu.version_d",
- elfcpp::SHT_GNU_verdef,
- elfcpp::SHF_ALLOC,
- false, ORDER_DYNAMIC_LINKER, false);
+ vdsec = this->choose_output_section(NULL, ".gnu.version_d",
+ elfcpp::SHT_GNU_verdef,
+ elfcpp::SHF_ALLOC,
+ false, ORDER_DYNAMIC_LINKER, false);
- unsigned char* vdbuf;
- unsigned int vdsize;
- unsigned int vdentries;
- versions->def_section_contents<size, big_endian>(&this->dynpool_, &vdbuf,
- &vdsize, &vdentries);
+ if (vdsec != NULL)
+ {
+ unsigned char* vdbuf;
+ unsigned int vdsize;
+ unsigned int vdentries;
+ versions->def_section_contents<size, big_endian>(&this->dynpool_,
+ &vdbuf, &vdsize,
+ &vdentries);
- Output_section_data* vddata =
- new Output_data_const_buffer(vdbuf, vdsize, 4, "** version defs");
+ Output_section_data* vddata =
+ new Output_data_const_buffer(vdbuf, vdsize, 4, "** version defs");
- vdsec->add_output_section_data(vddata);
- vdsec->set_link_section(dynstr);
- vdsec->set_info(vdentries);
+ vdsec->add_output_section_data(vddata);
+ vdsec->set_link_section(dynstr);
+ vdsec->set_info(vdentries);
- odyn->add_section_address(elfcpp::DT_VERDEF, vdsec);
- odyn->add_constant(elfcpp::DT_VERDEFNUM, vdentries);
+ if (odyn != NULL)
+ {
+ odyn->add_section_address(elfcpp::DT_VERDEF, vdsec);
+ odyn->add_constant(elfcpp::DT_VERDEFNUM, vdentries);
+ }
+ }
}
if (versions->any_needs())
elfcpp::SHF_ALLOC,
false, ORDER_DYNAMIC_LINKER, false);
- unsigned char* vnbuf;
- unsigned int vnsize;
- unsigned int vnentries;
- versions->need_section_contents<size, big_endian>(&this->dynpool_,
- &vnbuf, &vnsize,
- &vnentries);
+ if (vnsec != NULL)
+ {
+ unsigned char* vnbuf;
+ unsigned int vnsize;
+ unsigned int vnentries;
+ versions->need_section_contents<size, big_endian>(&this->dynpool_,
+ &vnbuf, &vnsize,
+ &vnentries);
- Output_section_data* vndata =
- new Output_data_const_buffer(vnbuf, vnsize, 4, "** version refs");
+ Output_section_data* vndata =
+ new Output_data_const_buffer(vnbuf, vnsize, 4, "** version refs");
- vnsec->add_output_section_data(vndata);
- vnsec->set_link_section(dynstr);
- vnsec->set_info(vnentries);
+ vnsec->add_output_section_data(vndata);
+ vnsec->set_link_section(dynstr);
+ vnsec->set_info(vnentries);
- odyn->add_section_address(elfcpp::DT_VERNEED, vnsec);
- odyn->add_constant(elfcpp::DT_VERNEEDNUM, vnentries);
+ if (odyn != NULL)
+ {
+ odyn->add_section_address(elfcpp::DT_VERNEED, vnsec);
+ odyn->add_constant(elfcpp::DT_VERNEEDNUM, vnentries);
+ }
+ }
}
}
void
Layout::create_interp(const Target* target)
{
+ gold_assert(this->interp_segment_ == NULL);
+
const char* interp = parameters->options().dynamic_linker();
if (interp == NULL)
{
elfcpp::SHF_ALLOC,
false, ORDER_INTERP,
false);
- osec->add_output_section_data(odata);
-
- if (!this->script_options_->saw_phdrs_clause())
- {
- Output_segment* oseg = this->make_output_segment(elfcpp::PT_INTERP,
- elfcpp::PF_R);
- oseg->add_output_section_to_nonload(osec, elfcpp::PF_R);
- }
+ if (osec != NULL)
+ osec->add_output_section_data(odata);
}
// Add dynamic tags for the PLT and the dynamic relocs. This is
// some targets have multiple reloc sections in PLT_REL.
// If DYN_REL is not NULL, it is used for DT_REL/DT_RELA,
-// DT_RELSZ/DT_RELASZ, DT_RELENT/DT_RELAENT.
+// DT_RELSZ/DT_RELASZ, DT_RELENT/DT_RELAENT. Again we use the output
+// section.
// If ADD_DEBUG is true, we add a DT_DEBUG entry when generating an
// executable.
use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA);
}
- if (dyn_rel != NULL && dyn_rel->output_section() != NULL)
+ if ((dyn_rel != NULL && dyn_rel->output_section() != NULL)
+ || (dynrel_includes_plt
+ && plt_rel != NULL
+ && plt_rel->output_section() != NULL))
{
+ bool have_dyn_rel = dyn_rel != NULL && dyn_rel->output_section() != NULL;
+ bool have_plt_rel = plt_rel != NULL && plt_rel->output_section() != NULL;
odyn->add_section_address(use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA,
- dyn_rel);
- if (plt_rel != NULL && dynrel_includes_plt)
- odyn->add_section_size(use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ,
- dyn_rel, plt_rel);
+ (have_dyn_rel
+ ? dyn_rel->output_section()
+ : plt_rel->output_section()));
+ elfcpp::DT size_tag = use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ;
+ if (have_dyn_rel && have_plt_rel && dynrel_includes_plt)
+ odyn->add_section_size(size_tag,
+ dyn_rel->output_section(),
+ plt_rel->output_section());
+ else if (have_dyn_rel)
+ odyn->add_section_size(size_tag, dyn_rel->output_section());
else
- odyn->add_section_size(use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ,
- dyn_rel);
+ odyn->add_section_size(size_tag, plt_rel->output_section());
const int size = parameters->target().get_size();
elfcpp::DT rel_tag;
int rel_size;
}
odyn->add_constant(rel_tag, rel_size);
- if (parameters->options().combreloc())
+ if (parameters->options().combreloc() && have_dyn_rel)
{
size_t c = dyn_rel->relative_reloc_count();
if (c > 0)
Layout::finish_dynamic_section(const Input_objects* input_objects,
const Symbol_table* symtab)
{
- if (!this->script_options_->saw_phdrs_clause())
+ if (!this->script_options_->saw_phdrs_clause()
+ && this->dynamic_section_ != NULL)
{
Output_segment* oseg = this->make_output_segment(elfcpp::PT_DYNAMIC,
(elfcpp::PF_R
}
Output_data_dynamic* const odyn = this->dynamic_data_;
+ if (odyn == NULL)
+ return;
for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
p != input_objects->dynobj_end();
++p)
{
- if (!(*p)->is_needed()
- && !(*p)->is_incremental()
- && (*p)->input_file()->options().as_needed())
+ if (!(*p)->is_needed() && (*p)->as_needed())
{
// This dynamic object was linked with --as-needed, but it
// is not needed.
{
case elfcpp::SHT_FINI_ARRAY:
odyn->add_section_address(elfcpp::DT_FINI_ARRAY, *p);
- odyn->add_section_size(elfcpp::DT_FINI_ARRAYSZ, *p);
+ odyn->add_section_size(elfcpp::DT_FINI_ARRAYSZ, *p);
break;
case elfcpp::SHT_INIT_ARRAY:
odyn->add_section_address(elfcpp::DT_INIT_ARRAY, *p);
- odyn->add_section_size(elfcpp::DT_INIT_ARRAYSZ, *p);
+ odyn->add_section_size(elfcpp::DT_INIT_ARRAYSZ, *p);
break;
case elfcpp::SHT_PREINIT_ARRAY:
odyn->add_section_address(elfcpp::DT_PREINIT_ARRAY, *p);
- odyn->add_section_size(elfcpp::DT_PREINIT_ARRAYSZ, *p);
+ odyn->add_section_size(elfcpp::DT_PREINIT_ARRAYSZ, *p);
break;
default:
break;
}
-
+
// Add a DT_RPATH entry if needed.
const General_options::Dir_list& rpath(parameters->options().rpath());
if (!rpath.empty())
{
std::string rpath_val;
for (General_options::Dir_list::const_iterator p = rpath.begin();
- p != rpath.end();
- ++p)
- {
- if (rpath_val.empty())
- rpath_val = p->name();
- else
- {
- // Eliminate duplicates.
- General_options::Dir_list::const_iterator q;
- for (q = rpath.begin(); q != p; ++q)
+ p != rpath.end();
+ ++p)
+ {
+ if (rpath_val.empty())
+ rpath_val = p->name();
+ else
+ {
+ // Eliminate duplicates.
+ General_options::Dir_list::const_iterator q;
+ for (q = rpath.begin(); q != p; ++q)
if (q->name() == p->name())
- break;
- if (q == p)
- {
- rpath_val += ':';
- rpath_val += p->name();
- }
- }
- }
-
- odyn->add_string(elfcpp::DT_RPATH, rpath_val);
- if (parameters->options().enable_new_dtags())
+ break;
+ if (q == p)
+ {
+ rpath_val += ':';
+ rpath_val += p->name();
+ }
+ }
+ }
+
+ if (!parameters->options().enable_new_dtags())
+ odyn->add_string(elfcpp::DT_RPATH, rpath_val);
+ else
odyn->add_string(elfcpp::DT_RUNPATH, rpath_val);
}
if (!this->script_options_->saw_sections_clause())
{
for (Segment_list::const_iterator p = this->segment_list_.begin();
- p != this->segment_list_.end();
- ++p)
- {
- if (((*p)->flags() & elfcpp::PF_W) == 0
- && (*p)->has_dynamic_reloc())
- {
- have_textrel = true;
- break;
- }
- }
+ p != this->segment_list_.end();
+ ++p)
+ {
+ if ((*p)->type() == elfcpp::PT_LOAD
+ && ((*p)->flags() & elfcpp::PF_W) == 0
+ && (*p)->has_dynamic_reloc())
+ {
+ have_textrel = true;
+ break;
+ }
+ }
}
else
{
// relocations. If those sections wind up in writable segments,
// then we have created an unnecessary DT_TEXTREL entry.
for (Section_list::const_iterator p = this->section_list_.begin();
- p != this->section_list_.end();
- ++p)
- {
- if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0
- && ((*p)->flags() & elfcpp::SHF_WRITE) == 0
- && ((*p)->has_dynamic_reloc()))
- {
- have_textrel = true;
- break;
- }
- }
- }
-
- // Add a DT_FLAGS entry. We add it even if no flags are set so that
- // post-link tools can easily modify these flags if desired.
+ p != this->section_list_.end();
+ ++p)
+ {
+ if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0
+ && ((*p)->flags() & elfcpp::SHF_WRITE) == 0
+ && (*p)->has_dynamic_reloc())
+ {
+ have_textrel = true;
+ break;
+ }
+ }
+ }
+
+ if (parameters->options().filter() != NULL)
+ odyn->add_string(elfcpp::DT_FILTER, parameters->options().filter());
+ if (parameters->options().any_auxiliary())
+ {
+ for (options::String_set::const_iterator p =
+ parameters->options().auxiliary_begin();
+ p != parameters->options().auxiliary_end();
+ ++p)
+ odyn->add_string(elfcpp::DT_AUXILIARY, *p);
+ }
+
+ // Add a DT_FLAGS entry if necessary.
unsigned int flags = 0;
if (have_textrel)
{
}
if (parameters->options().now())
flags |= elfcpp::DF_BIND_NOW;
- odyn->add_constant(elfcpp::DT_FLAGS, flags);
+ if (flags != 0)
+ odyn->add_constant(elfcpp::DT_FLAGS, flags);
flags = 0;
if (parameters->options().initfirst())
flags |= elfcpp::DF_1_ORIGIN;
if (parameters->options().now())
flags |= elfcpp::DF_1_NOW;
- if (flags)
+ if (parameters->options().Bgroup())
+ flags |= elfcpp::DF_1_GROUP;
+ if (flags != 0)
odyn->add_constant(elfcpp::DT_FLAGS_1, flags);
}
Layout::set_dynamic_symbol_size(const Symbol_table* symtab)
{
Output_data_dynamic* const odyn = this->dynamic_data_;
+ if (odyn == NULL)
+ return;
odyn->finalize_data_size();
+ if (this->dynamic_symbol_ == NULL)
+ return;
off_t data_size = odyn->data_size();
const int size = parameters->target().get_size();
if (size == 32)
// based on the GNU linker default ELF linker script.
#define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
+#define MAPPING_INIT_EXACT(f, t) { f, 0, t, sizeof(t) - 1 }
const Layout::Section_name_mapping Layout::section_name_mapping[] =
{
MAPPING_INIT(".text.", ".text"),
- MAPPING_INIT(".ctors.", ".ctors"),
- MAPPING_INIT(".dtors.", ".dtors"),
MAPPING_INIT(".rodata.", ".rodata"),
- MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"),
- MAPPING_INIT(".data.rel.ro", ".data.rel.ro"),
+ MAPPING_INIT(".data.rel.ro.local.", ".data.rel.ro.local"),
+ MAPPING_INIT_EXACT(".data.rel.ro.local", ".data.rel.ro.local"),
+ MAPPING_INIT(".data.rel.ro.", ".data.rel.ro"),
+ MAPPING_INIT_EXACT(".data.rel.ro", ".data.rel.ro"),
MAPPING_INIT(".data.", ".data"),
MAPPING_INIT(".bss.", ".bss"),
MAPPING_INIT(".tdata.", ".tdata"),
MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
};
#undef MAPPING_INIT
+#undef MAPPING_INIT_EXACT
const int Layout::section_name_mapping_count =
(sizeof(Layout::section_name_mapping)
// length of NAME.
const char*
-Layout::output_section_name(const char* name, size_t* plen)
+Layout::output_section_name(const Relobj* relobj, const char* name,
+ size_t* plen)
{
// gcc 4.3 generates the following sorts of section names when it
// needs a section name specific to a function:
const Section_name_mapping* psnm = section_name_mapping;
for (int i = 0; i < section_name_mapping_count; ++i, ++psnm)
{
- if (strncmp(name, psnm->from, psnm->fromlen) == 0)
+ if (psnm->fromlen > 0)
+ {
+ if (strncmp(name, psnm->from, psnm->fromlen) == 0)
+ {
+ *plen = psnm->tolen;
+ return psnm->to;
+ }
+ }
+ else
+ {
+ if (strcmp(name, psnm->from) == 0)
+ {
+ *plen = psnm->tolen;
+ return psnm->to;
+ }
+ }
+ }
+
+ // As an additional complication, .ctors sections are output in
+ // either .ctors or .init_array sections, and .dtors sections are
+ // output in either .dtors or .fini_array sections.
+ if (is_prefix_of(".ctors.", name) || is_prefix_of(".dtors.", name))
+ {
+ if (parameters->options().ctors_in_init_array())
+ {
+ *plen = 11;
+ return name[1] == 'c' ? ".init_array" : ".fini_array";
+ }
+ else
+ {
+ *plen = 6;
+ return name[1] == 'c' ? ".ctors" : ".dtors";
+ }
+ }
+ if (parameters->options().ctors_in_init_array()
+ && (strcmp(name, ".ctors") == 0 || strcmp(name, ".dtors") == 0))
+ {
+ // To make .init_array/.fini_array work with gcc we must exclude
+ // .ctors and .dtors sections from the crtbegin and crtend
+ // files.
+ if (relobj == NULL
+ || (!Layout::match_file_name(relobj, "crtbegin")
+ && !Layout::match_file_name(relobj, "crtend")))
{
- *plen = psnm->tolen;
- return psnm->to;
+ *plen = 11;
+ return name[1] == 'c' ? ".init_array" : ".fini_array";
}
}
return name;
}
+// Return true if RELOBJ is an input file whose base name matches
+// FILE_NAME. The base name must have an extension of ".o", and must
+// be exactly FILE_NAME.o or FILE_NAME, one character, ".o". This is
+// to match crtbegin.o as well as crtbeginS.o without getting confused
+// by other possibilities. Overall matching the file name this way is
+// a dreadful hack, but the GNU linker does it in order to better
+// support gcc, and we need to be compatible.
+
+bool
+Layout::match_file_name(const Relobj* relobj, const char* match)
+{
+ const std::string& file_name(relobj->name());
+ const char* base_name = lbasename(file_name.c_str());
+ size_t match_len = strlen(match);
+ if (strncmp(base_name, match, match_len) != 0)
+ return false;
+ size_t base_len = strlen(base_name);
+ if (base_len != match_len + 2 && base_len != match_len + 3)
+ return false;
+ return memcmp(base_name + base_len - 2, ".o", 2) == 0;
+}
+
// Check if a comdat group or .gnu.linkonce section with the given
// NAME is selected for the link. If there is already a section,
// *KEPT_SECTION is set to point to the existing section and the
unsigned int shndx,
bool is_comdat,
bool is_group_name,
- Kept_section** kept_section)
+ Kept_section** kept_section)
{
// It's normal to see a couple of entries here, for the x86 thunk
// sections. If we see more than a few, we're linking a C++
// If the kept group is from a plugin object, and we're in the
// replacement phase, accept the new one as a replacement.
if (ins.first->second.object() == NULL
- && parameters->options().plugins()->in_replacement_phase())
- {
+ && parameters->options().plugins()->in_replacement_phase())
+ {
ins.first->second.set_object(object);
ins.first->second.set_shndx(shndx);
- return true;
- }
+ return true;
+ }
return false;
}
else if (is_group_name)
section_list->push_back(*p);
}
+// Store the executable sections into the section list.
+
+void
+Layout::get_executable_sections(Section_list* section_list) const
+{
+ for (Section_list::const_iterator p = this->section_list_.begin();
+ p != this->section_list_.end();
+ ++p)
+ if (((*p)->flags() & (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR))
+ == (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR))
+ section_list->push_back(*p);
+}
+
// Create an output segment.
Output_segment*
this->tls_segment_ = oseg;
else if (type == elfcpp::PT_GNU_RELRO)
this->relro_segment_ = oseg;
+ else if (type == elfcpp::PT_INTERP)
+ this->interp_segment_ = oseg;
return oseg;
}
return 0;
}
+// Return the section index of the normal symbol table. It may have
+// been stripped by the -s/--strip-all option.
+
+unsigned int
+Layout::symtab_section_shndx() const
+{
+ if (this->symtab_section_ != NULL)
+ return this->symtab_section_->out_shndx();
+ return 0;
+}
+
// Write out the Output_sections. Most won't have anything to write,
// since most of the data will come from input sections which are
// handled elsewhere. But some Output_sections do have Output_data.
p != this->special_output_list_.end();
++p)
(*p)->write(of);
+
+ // Write out the Output_data which are not in an Output_section
+ // and are regenerated in each iteration of relaxation.
+ for (Data_list::const_iterator p = this->relax_output_list_.begin();
+ p != this->relax_output_list_.end();
+ ++p)
+ (*p)->write(of);
}
// Write out the Output_sections which can only be written after the
this->section_headers_->write(of);
}
-// If the build ID requires computing a checksum, do so here, and
-// write it out. We compute a checksum over the entire file because
-// that is simplest.
+// Build IDs can be computed as a "flat" sha1 or md5 of a string of bytes,
+// or as a "tree" where each chunk of the string is hashed and then those
+// hashes are put into a (much smaller) string which is hashed with sha1.
+// We compute a checksum over the entire file because that is simplest.
+
+Task_token*
+Layout::queue_build_id_tasks(Workqueue* workqueue, Task_token* build_id_blocker,
+ Output_file* of)
+{
+ const size_t filesize = (this->output_file_size() <= 0 ? 0
+ : static_cast<size_t>(this->output_file_size()));
+ if (this->build_id_note_ != NULL
+ && strcmp(parameters->options().build_id(), "tree") == 0
+ && parameters->options().build_id_chunk_size_for_treehash() > 0
+ && filesize > 0
+ && (filesize >=
+ parameters->options().build_id_min_file_size_for_treehash()))
+ {
+ static const size_t MD5_OUTPUT_SIZE_IN_BYTES = 16;
+ const size_t chunk_size =
+ parameters->options().build_id_chunk_size_for_treehash();
+ const size_t num_hashes = ((filesize - 1) / chunk_size) + 1;
+ Task_token* post_hash_tasks_blocker = new Task_token(true);
+ post_hash_tasks_blocker->add_blockers(num_hashes);
+ this->size_of_array_of_hashes_ = num_hashes * MD5_OUTPUT_SIZE_IN_BYTES;
+ const unsigned char* src = of->get_input_view(0, filesize);
+ this->input_view_ = src;
+ unsigned char *dst = new unsigned char[this->size_of_array_of_hashes_];
+ this->array_of_hashes_ = dst;
+ for (size_t i = 0, src_offset = 0; i < num_hashes;
+ i++, dst += MD5_OUTPUT_SIZE_IN_BYTES, src_offset += chunk_size)
+ {
+ size_t size = std::min(chunk_size, filesize - src_offset);
+ workqueue->queue(new Hash_task(src + src_offset,
+ size,
+ dst,
+ build_id_blocker,
+ post_hash_tasks_blocker));
+ }
+ return post_hash_tasks_blocker;
+ }
+ return build_id_blocker;
+}
+
+// If a tree-style build ID was requested, the parallel part of that computation
+// is already done, and the final hash-of-hashes is computed here. For other
+// types of build IDs, all the work is done here.
void
Layout::write_build_id(Output_file* of) const
if (this->build_id_note_ == NULL)
return;
- const unsigned char* iv = of->get_input_view(0, this->output_file_size_);
-
unsigned char* ov = of->get_output_view(this->build_id_note_->offset(),
this->build_id_note_->data_size());
- const char* style = parameters->options().build_id();
- if (strcmp(style, "sha1") == 0)
+ if (this->array_of_hashes_ == NULL)
{
- sha1_ctx ctx;
- sha1_init_ctx(&ctx);
- sha1_process_bytes(iv, this->output_file_size_, &ctx);
- sha1_finish_ctx(&ctx, ov);
+ const size_t output_file_size = this->output_file_size();
+ const unsigned char* iv = of->get_input_view(0, output_file_size);
+ const char* style = parameters->options().build_id();
+
+ // If we get here with style == "tree" then the output must be
+ // too small for chunking, and we use SHA-1 in that case.
+ if ((strcmp(style, "sha1") == 0) || (strcmp(style, "tree") == 0))
+ sha1_buffer(reinterpret_cast<const char*>(iv), output_file_size, ov);
+ else if (strcmp(style, "md5") == 0)
+ md5_buffer(reinterpret_cast<const char*>(iv), output_file_size, ov);
+ else
+ gold_unreachable();
+
+ of->free_input_view(0, output_file_size, iv);
}
- else if (strcmp(style, "md5") == 0)
+ else
{
- md5_ctx ctx;
- md5_init_ctx(&ctx);
- md5_process_bytes(iv, this->output_file_size_, &ctx);
- md5_finish_ctx(&ctx, ov);
+ // Non-overlapping substrings of the output file have been hashed.
+ // Compute SHA-1 hash of the hashes.
+ sha1_buffer(reinterpret_cast<const char*>(this->array_of_hashes_),
+ this->size_of_array_of_hashes_, ov);
+ delete[] this->array_of_hashes_;
+ of->free_input_view(0, this->output_file_size(), this->input_view_);
}
- else
- gold_unreachable();
of->write_output_view(this->build_id_note_->offset(),
this->build_id_note_->data_size(),
ov);
-
- of->free_input_view(0, this->output_file_size_, iv);
}
// Write out a binary file. This is called after the link is
// Close_task_runner methods.
-// Run the task--close the file.
+// Finish up the build ID computation, if necessary, and write a binary file,
+// if necessary. Then close the output file.
void
Close_task_runner::run(Workqueue*, const Task*)
{
- // If we need to compute a checksum for the BUILD if, we do so here.
+ // At this point the multi-threaded part of the build ID computation,
+ // if any, is done. See queue_build_id_tasks().
this->layout_->write_build_id(this->of_);
// If we've been asked to create a binary file, we do so here.
off_t* off);
#endif
+#ifdef HAVE_TARGET_32_LITTLE
+template
+void
+Layout::add_to_gdb_index(bool is_type_unit,
+ Sized_relobj<32, false>* object,
+ const unsigned char* symbols,
+ off_t symbols_size,
+ unsigned int shndx,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type);
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+void
+Layout::add_to_gdb_index(bool is_type_unit,
+ Sized_relobj<32, true>* object,
+ const unsigned char* symbols,
+ off_t symbols_size,
+ unsigned int shndx,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type);
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+void
+Layout::add_to_gdb_index(bool is_type_unit,
+ Sized_relobj<64, false>* object,
+ const unsigned char* symbols,
+ off_t symbols_size,
+ unsigned int shndx,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type);
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+void
+Layout::add_to_gdb_index(bool is_type_unit,
+ Sized_relobj<64, true>* object,
+ const unsigned char* symbols,
+ off_t symbols_size,
+ unsigned int shndx,
+ unsigned int reloc_shndx,
+ unsigned int reloc_type);
+#endif
+
} // End namespace gold.