#include "symtab.h"
#include "dynobj.h"
#include "ehframe.h"
+#include "compressed_output.h"
#include "layout.h"
namespace gold
// have been read.
void
-Layout_task_runner::run(Workqueue* workqueue)
+Layout_task_runner::run(Workqueue* workqueue, const Task* task)
{
off_t file_size = this->layout_->finalize(this->input_objects_,
- this->symtab_);
+ this->symtab_,
+ task);
// Now we know the final size of the output file and we know where
// each piece of information goes.
eh_frame_section_(NULL), output_file_size_(-1),
input_requires_executable_stack_(false),
input_with_gnu_stack_note_(false),
- input_without_gnu_stack_note_(false)
+ input_without_gnu_stack_note_(false),
+ has_static_tls_(false),
+ any_postprocessing_sections_(false)
{
// Make space for more than enough segments for a typical file.
// This is just for efficiency--it's OK if we wind up needing more.
// Canonicalize the section name.
Stringpool::Key name_key;
- name = this->namepool_.add_prefix(name, len, &name_key);
+ name = this->namepool_.add_with_length(name, len, true, &name_key);
// Find the output section. The output section is selected based on
// the section name, type, and flags.
return ret;
}
+// Sometimes we compress sections. This is typically done for
+// sections that are not part of normal program execution (such as
+// .debug_* sections), and where the readers of these sections know
+// how to deal with compressed sections. (To make it easier for them,
+// we will rename the ouput section in such cases from .foo to
+// .foo.zlib.nnnn, where nnnn is the uncompressed size.) This routine
+// doesn't say for certain whether we'll compress -- it depends on
+// commandline options as well -- just whether this section is a
+// candidate for compression.
+
+static bool
+is_compressible_debug_section(const char* secname)
+{
+ return (strncmp(secname, ".debug", sizeof(".debug") - 1) == 0);
+}
+
// Make a new Output_section, and attach it to segments as
// appropriate.
Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
elfcpp::Elf_Xword flags)
{
- Output_section* os = new Output_section(this->options_, name, type, flags);
+ Output_section* os;
+ if ((flags & elfcpp::SHF_ALLOC) == 0
+ && this->options_.compress_debug_sections()
+ && is_compressible_debug_section(name))
+ os = new Output_compressed_section(&this->options_, name, type, flags);
+ else
+ os = new Output_section(name, type, flags);
+
this->section_list_.push_back(os);
if ((flags & elfcpp::SHF_ALLOC) == 0)
// This function returns the size of the output file.
off_t
-Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab)
+Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab,
+ const Task* task)
{
Target* const target = input_objects->target();
target->finalize_sections(this);
+ this->count_local_symbols(task, input_objects);
+
this->create_gold_note();
this->create_executable_stack_info(target);
std::vector<Symbol*> dynamic_symbols;
unsigned int local_dynamic_count;
Versions versions;
- this->create_dynamic_symtab(target, symtab, &dynstr,
+ this->create_dynamic_symtab(input_objects, target, symtab, &dynstr,
&local_dynamic_count, &dynamic_symbols,
&versions);
off_t off = this->set_segment_offsets(target, load_seg, &shndx);
// Create the symbol table sections.
- this->create_symtab_sections(input_objects, symtab, &off);
+ this->create_symtab_sections(input_objects, symtab, task, &off);
+ if (!parameters->doing_static_link())
+ this->assign_local_dynsym_offsets(input_objects);
// Create the .shstrtab section.
Output_section* shstrtab_section = this->create_shstrtab();
// Create the section table header.
this->create_shdrs(&off);
+ // If there are no sections which require postprocessing, we can
+ // handle the section names now, and avoid a resize later.
+ if (!this->any_postprocessing_sections_)
+ off = this->set_section_offsets(off,
+ STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS);
+
file_header->set_section_info(this->section_headers_, shstrtab_section);
// Now we know exactly where everything goes in the output file
// Find the PT_LOAD segments, and set their addresses and offsets
// and their section's addresses and offsets.
uint64_t addr;
- if (options_.user_set_text_segment_address())
+ if (parameters->output_is_shared())
+ addr = 0;
+ else if (options_.user_set_text_segment_address())
addr = options_.text_segment_address();
else
addr = target->default_text_segment_address();
(*p)->set_offset();
}
+ // Set the TLS offsets for each section in the PT_TLS segment.
+ if (this->tls_segment_ != NULL)
+ this->tls_segment_->set_tls_offsets();
+
return off;
}
if (*p == this->symtab_section_)
continue;
+ if (pass == BEFORE_INPUT_SECTIONS_PASS
+ && (*p)->requires_postprocessing())
+ {
+ (*p)->create_postprocessing_buffer();
+ this->any_postprocessing_sections_ = true;
+ }
+
if (pass == BEFORE_INPUT_SECTIONS_PASS
&& (*p)->after_input_sections())
continue;
- else if (pass == AFTER_INPUT_SECTIONS_PASS
+ else if (pass == POSTPROCESSING_SECTIONS_PASS
&& (!(*p)->after_input_sections()
|| (*p)->type() == elfcpp::SHT_STRTAB))
continue;
- else if (pass == STRTAB_AFTER_INPUT_SECTIONS_PASS
+ else if (pass == STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
&& (!(*p)->after_input_sections()
|| (*p)->type() != elfcpp::SHT_STRTAB))
continue;
(*p)->set_file_offset(off);
(*p)->finalize_data_size();
off += (*p)->data_size();
+
+ // At this point the name must be set.
+ if (pass != STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS)
+ this->namepool_.add((*p)->name(), false, NULL);
}
return off;
}
-// Allow any section not associated with a segment to change its
-// output section name at the last minute.
-
-void
-Layout::modify_section_names()
-{
- for (Section_list::iterator p = this->unattached_section_list_.begin();
- p != this->unattached_section_list_.end();
- ++p)
- if ((*p)->maybe_modify_output_section_name())
- this->namepool_.add((*p)->name(), true, NULL);
-}
-
// Set the section indexes of all the sections not associated with a
// segment.
return shndx;
}
+// Count the local symbols in the regular symbol table and the dynamic
+// symbol table, and build the respective string pools.
+
+void
+Layout::count_local_symbols(const Task* task,
+ const Input_objects* input_objects)
+{
+ // First, figure out an upper bound on the number of symbols we'll
+ // be inserting into each pool. This helps us create the pools with
+ // the right size, to avoid unnecessary hashtable resizing.
+ unsigned int symbol_count = 0;
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ symbol_count += (*p)->local_symbol_count();
+
+ // Go from "upper bound" to "estimate." We overcount for two
+ // reasons: we double-count symbols that occur in more than one
+ // object file, and we count symbols that are dropped from the
+ // output. Add it all together and assume we overcount by 100%.
+ symbol_count /= 2;
+
+ // We assume all symbols will go into both the sympool and dynpool.
+ this->sympool_.reserve(symbol_count);
+ this->dynpool_.reserve(symbol_count);
+
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ {
+ Task_lock_obj<Object> tlo(task, *p);
+ (*p)->count_local_symbols(&this->sympool_, &this->dynpool_);
+ }
+}
+
// Create the symbol table sections. Here we also set the final
// values of the symbols. At this point all the loadable sections are
// fully laid out.
void
Layout::create_symtab_sections(const Input_objects* input_objects,
Symbol_table* symtab,
+ const Task* task,
off_t* poff)
{
int symsize;
p != input_objects->relobj_end();
++p)
{
- Task_lock_obj<Object> tlo(**p);
unsigned int index = (*p)->finalize_local_symbols(local_symbol_index,
- off,
- &this->sympool_);
+ off);
off += (index - local_symbol_index) * symsize;
local_symbol_index = index;
}
== this->dynsym_section_->data_size() - locsize);
}
- off = symtab->finalize(local_symcount, off, dynoff, dyn_global_index,
+ off = symtab->finalize(task, local_symcount, off, dynoff, dyn_global_index,
dyncount, &this->sympool_);
if (!parameters->strip_all())
// Create the dynamic symbol table.
void
-Layout::create_dynamic_symtab(const Target* target, Symbol_table* symtab,
+Layout::create_dynamic_symtab(const Input_objects* input_objects,
+ const Target* target, Symbol_table* symtab,
Output_section **pdynstr,
unsigned int* plocal_dynamic_count,
std::vector<Symbol*>* pdynamic_symbols,
}
}
- // FIXME: Some targets apparently require local symbols in the
- // dynamic symbol table. Here is where we will have to count them,
- // and set the dynamic symbol indexes, and add the names to
- // this->dynpool_.
+ // Count the local symbols that need to go in the dynamic symbol table,
+ // and set the dynamic symbol indexes.
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ {
+ unsigned int new_index = (*p)->set_local_dynsym_indexes(index);
+ index = new_index;
+ }
unsigned int local_symcount = index;
*plocal_dynamic_count = local_symcount;
odyn->add_section_address(elfcpp::DT_HASH, hashsec);
}
+// Assign offsets to each local portion of the dynamic symbol table.
+
+void
+Layout::assign_local_dynsym_offsets(const Input_objects* input_objects)
+{
+ Output_section* dynsym = this->dynsym_section_;
+ gold_assert(dynsym != NULL);
+
+ off_t off = dynsym->offset();
+
+ // Skip the dummy symbol at the start of the section.
+ off += dynsym->entsize();
+
+ for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+ p != input_objects->relobj_end();
+ ++p)
+ {
+ unsigned int count = (*p)->set_local_dynsym_offset(off);
+ off += count * dynsym->entsize();
+ }
+}
+
// Create the version sections.
void
// post-link tools can easily modify these flags if desired.
unsigned int flags = 0;
if (have_textrel)
- flags |= elfcpp::DF_TEXTREL;
+ {
+ // Add a DT_TEXTREL for compatibility with older loaders.
+ odyn->add_constant(elfcpp::DT_TEXTREL, 0);
+ flags |= elfcpp::DF_TEXTREL;
+ }
+ if (parameters->output_is_shared() && this->has_static_tls())
+ flags |= elfcpp::DF_STATIC_TLS;
odyn->add_constant(elfcpp::DT_FLAGS, flags);
}
// file size. Note we finalize the .shstrab last, to allow the
// after_input_section sections to modify their section-names before
// writing.
- off_t off = this->output_file_size_;
- off = this->set_section_offsets(off, AFTER_INPUT_SECTIONS_PASS);
-
- // Determine the final section names as well (at least, for sections
- // that we haven't written yet).
- this->modify_section_names();
-
- // Now that we've finalized the names, we can finalize the shstrab.
- off = this->set_section_offsets(off, STRTAB_AFTER_INPUT_SECTIONS_PASS);
-
- if (off > this->output_file_size_)
+ if (this->any_postprocessing_sections_)
{
- of->resize(off);
- this->output_file_size_ = off;
+ off_t off = this->output_file_size_;
+ off = this->set_section_offsets(off, POSTPROCESSING_SECTIONS_PASS);
+
+ // Now that we've finalized the names, we can finalize the shstrab.
+ off =
+ this->set_section_offsets(off,
+ STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS);
+
+ if (off > this->output_file_size_)
+ {
+ of->resize(off);
+ this->output_file_size_ = off;
+ }
}
for (Section_list::const_iterator p = this->section_list_.begin();
(*p)->write(of);
}
- for (Section_list::const_iterator p = this->unattached_section_list_.begin();
- p != this->unattached_section_list_.end();
- ++p)
- {
- if ((*p)->after_input_sections())
- (*p)->write(of);
- }
-
this->section_headers_->write(of);
}
+// Print statistical information to stderr. This is used for --stats.
+
+void
+Layout::print_stats() const
+{
+ this->namepool_.print_stats("section name pool");
+ this->sympool_.print_stats("output symbol name pool");
+ this->dynpool_.print_stats("dynamic name pool");
+
+ for (Section_list::const_iterator p = this->section_list_.begin();
+ p != this->section_list_.end();
+ ++p)
+ (*p)->print_merge_stats();
+}
+
// Write_sections_task methods.
// We can always run this task.
-Task::Is_runnable_type
-Write_sections_task::is_runnable(Workqueue*)
+Task_token*
+Write_sections_task::is_runnable()
{
- return IS_RUNNABLE;
+ return NULL;
}
// We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
// when finished.
-class Write_sections_task::Write_sections_locker : public Task_locker
-{
- public:
- Write_sections_locker(Task_token& output_sections_blocker,
- Task_token& final_blocker,
- Workqueue* workqueue)
- : output_sections_block_(output_sections_blocker, workqueue),
- final_block_(final_blocker, workqueue)
- { }
-
- private:
- Task_block_token output_sections_block_;
- Task_block_token final_block_;
-};
-
-Task_locker*
-Write_sections_task::locks(Workqueue* workqueue)
+void
+Write_sections_task::locks(Task_locker* tl)
{
- return new Write_sections_locker(*this->output_sections_blocker_,
- *this->final_blocker_,
- workqueue);
+ tl->add(this, this->output_sections_blocker_);
+ tl->add(this, this->final_blocker_);
}
// Run the task--write out the data.
// We can always run this task.
-Task::Is_runnable_type
-Write_data_task::is_runnable(Workqueue*)
+Task_token*
+Write_data_task::is_runnable()
{
- return IS_RUNNABLE;
+ return NULL;
}
// We need to unlock FINAL_BLOCKER when finished.
-Task_locker*
-Write_data_task::locks(Workqueue* workqueue)
+void
+Write_data_task::locks(Task_locker* tl)
{
- return new Task_locker_block(*this->final_blocker_, workqueue);
+ tl->add(this, this->final_blocker_);
}
// Run the task--write out the data.
// We can always run this task.
-Task::Is_runnable_type
-Write_symbols_task::is_runnable(Workqueue*)
+Task_token*
+Write_symbols_task::is_runnable()
{
- return IS_RUNNABLE;
+ return NULL;
}
// We need to unlock FINAL_BLOCKER when finished.
-Task_locker*
-Write_symbols_task::locks(Workqueue* workqueue)
+void
+Write_symbols_task::locks(Task_locker* tl)
{
- return new Task_locker_block(*this->final_blocker_, workqueue);
+ tl->add(this, this->final_blocker_);
}
// Run the task--write out the symbols.
// We can only run this task after the input sections have completed.
-Task::Is_runnable_type
-Write_after_input_sections_task::is_runnable(Workqueue*)
+Task_token*
+Write_after_input_sections_task::is_runnable()
{
if (this->input_sections_blocker_->is_blocked())
- return IS_BLOCKED;
- return IS_RUNNABLE;
+ return this->input_sections_blocker_;
+ return NULL;
}
// We need to unlock FINAL_BLOCKER when finished.
-Task_locker*
-Write_after_input_sections_task::locks(Workqueue* workqueue)
+void
+Write_after_input_sections_task::locks(Task_locker* tl)
{
- return new Task_locker_block(*this->final_blocker_, workqueue);
+ tl->add(this, this->final_blocker_);
}
// Run the task.
// Run the task--close the file.
void
-Close_task_runner::run(Workqueue*)
+Close_task_runner::run(Workqueue*, const Task*)
{
this->of_->close();
}