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authorIan Lance Taylor <iant@google.com>2006-10-20 20:40:49 +0000
committerIan Lance Taylor <iant@google.com>2006-10-20 20:40:49 +0000
commit92e059d8dc78c3f65e29e48e368f6e47ea0ab671 (patch)
treef448eb3317d9cbb0f5946422cc28ef157a5f65cb /gold/reloc.cc
parentaf4658dc3db33004d6166b161588221ecb463a5f (diff)
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Framework for relocation scanning. Implement simple static TLS
relocations.
Diffstat (limited to 'gold/reloc.cc')
-rw-r--r--gold/reloc.cc311
1 files changed, 290 insertions, 21 deletions
diff --git a/gold/reloc.cc b/gold/reloc.cc
index 905eeae..bb672e4 100644
--- a/gold/reloc.cc
+++ b/gold/reloc.cc
@@ -10,6 +10,86 @@
namespace gold
{
+// Read_relocs methods.
+
+// These tasks just read the relocation information from the file.
+// After reading it, the start another task to process the
+// information. These tasks requires access to the file.
+
+Task::Is_runnable_type
+Read_relocs::is_runnable(Workqueue*)
+{
+ return this->object_->is_locked() ? IS_LOCKED : IS_RUNNABLE;
+}
+
+// Lock the file.
+
+Task_locker*
+Read_relocs::locks(Workqueue*)
+{
+ return new Task_locker_obj<Object>(*this->object_);
+}
+
+// Read the relocations and then start a Scan_relocs_task.
+
+void
+Read_relocs::run(Workqueue* workqueue)
+{
+ Read_relocs_data *rd = new Read_relocs_data;
+ this->object_->read_relocs(rd);
+ workqueue->queue_front(new Scan_relocs(this->options_, this->symtab_,
+ this->object_, rd, this->symtab_lock_,
+ this->blocker_));
+}
+
+// Scan_relocs methods.
+
+// These tasks scan the relocations read by Read_relocs and mark up
+// the symbol table to indicate which relocations are required. We
+// use a lock on the symbol table to keep them from interfering with
+// each other.
+
+Task::Is_runnable_type
+Scan_relocs::is_runnable(Workqueue*)
+{
+ return this->symtab_lock_->is_writable() ? IS_RUNNABLE : IS_LOCKED;
+}
+
+// Return the locks we hold: one on the file, one on the symbol table
+// and one blocker.
+
+class Scan_relocs::Scan_relocs_locker : public Task_locker
+{
+ public:
+ Scan_relocs_locker(Object* object, Task_token& symtab_lock, Task* task,
+ Task_token& blocker, Workqueue* workqueue)
+ : objlock_(*object), symtab_locker_(symtab_lock, task),
+ blocker_(blocker, workqueue)
+ { }
+
+ private:
+ Task_locker_obj<Object> objlock_;
+ Task_locker_write symtab_locker_;
+ Task_locker_block blocker_;
+};
+
+Task_locker*
+Scan_relocs::locks(Workqueue* workqueue)
+{
+ return new Scan_relocs_locker(this->object_, *this->symtab_lock_, this,
+ *this->blocker_, workqueue);
+}
+
+// Scan the relocs.
+
+void
+Scan_relocs::run(Workqueue*)
+{
+ this->object_->scan_relocs(this->options_, this->symtab_, this->rd_);
+ delete this->rd_;
+ this->rd_ = NULL;
+}
+
// Relocate_task methods.
// These tasks are always runnable.
@@ -48,17 +128,154 @@ Relocate_task::locks(Workqueue* workqueue)
void
Relocate_task::run(Workqueue*)
{
- this->object_->relocate(this->options_, this->symtab_, this->sympool_,
+ this->object_->relocate(this->options_, this->symtab_, this->layout_,
this->of_);
}
+// Read the relocs and local symbols from the object file and store
+// the information in RD.
+
+template<int size, bool big_endian>
+void
+Sized_object<size, big_endian>::do_read_relocs(Read_relocs_data* rd)
+{
+ rd->relocs.clear();
+
+ unsigned int shnum = this->shnum();
+ if (shnum == 0)
+ return;
+
+ rd->relocs.reserve(shnum / 2);
+
+ const unsigned char *pshdrs = this->get_view(this->shoff_,
+ shnum * This::shdr_size);
+ // Skip the first, dummy, section.
+ const unsigned char *ps = pshdrs + This::shdr_size;
+ for (unsigned int i = 1; i < shnum; ++i, ps += This::shdr_size)
+ {
+ typename This::Shdr shdr(ps);
+
+ unsigned int sh_type = shdr.get_sh_type();
+ if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
+ continue;
+
+ unsigned int shndx = shdr.get_sh_info();
+ if (shndx >= shnum)
+ {
+ fprintf(stderr, _("%s: %s: relocation section %u has bad info %u\n"),
+ program_name, this->name().c_str(), i, shndx);
+ gold_exit(false);
+ }
+
+ if (!this->is_section_included(shndx))
+ continue;
+
+ if (shdr.get_sh_link() != this->symtab_shnum_)
+ {
+ fprintf(stderr,
+ _("%s: %s: relocation section %u uses unexpected "
+ "symbol table %u\n"),
+ program_name, this->name().c_str(), i, shdr.get_sh_link());
+ gold_exit(false);
+ }
+
+ off_t sh_size = shdr.get_sh_size();
+
+ unsigned int reloc_size;
+ if (sh_type == elfcpp::SHT_REL)
+ reloc_size = elfcpp::Elf_sizes<size>::rel_size;
+ else
+ reloc_size = elfcpp::Elf_sizes<size>::rela_size;
+ if (reloc_size != shdr.get_sh_entsize())
+ {
+ fprintf(stderr,
+ _("%s: %s: unexpected entsize for reloc section %u: "
+ "%lu != %u"),
+ program_name, this->name().c_str(), i,
+ static_cast<unsigned long>(shdr.get_sh_entsize()),
+ reloc_size);
+ gold_exit(false);
+ }
+
+ size_t reloc_count = sh_size / reloc_size;
+ if (reloc_count * reloc_size != sh_size)
+ {
+ fprintf(stderr, _("%s: %s: reloc section %u size %lu uneven"),
+ program_name, this->name().c_str(), i,
+ static_cast<unsigned long>(sh_size));
+ gold_exit(false);
+ }
+
+ rd->relocs.push_back(Section_relocs());
+ Section_relocs& sr(rd->relocs.back());
+ sr.reloc_shndx = i;
+ sr.data_shndx = shndx;
+ sr.contents = this->get_lasting_view(shdr.get_sh_offset(), sh_size);
+ sr.sh_type = sh_type;
+ sr.reloc_count = reloc_count;
+ }
+
+ // Read the local symbols.
+ if (this->symtab_shnum_ == 0 || this->local_symbol_count_ == 0)
+ rd->local_symbols = NULL;
+ else
+ {
+ typename This::Shdr symtabshdr(pshdrs
+ + this->symtab_shnum_ * This::shdr_size);
+ assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+ const int sym_size = This::sym_size;
+ const unsigned int loccount = this->local_symbol_count_;
+ assert(loccount == symtabshdr.get_sh_info());
+ off_t locsize = loccount * sym_size;
+ rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(),
+ locsize);
+ }
+}
+
+// Scan the relocs and adjust the symbol table. This looks for
+// relocations which require GOT/PLT/COPY relocations.
+
+template<int size, bool big_endian>
+void
+Sized_object<size, big_endian>::do_scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Read_relocs_data* rd)
+{
+ Sized_target<size, big_endian>* target = this->sized_target();
+
+ const unsigned char* local_symbols;
+ if (rd->local_symbols == NULL)
+ local_symbols = NULL;
+ else
+ local_symbols = rd->local_symbols->data();
+
+ for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
+ p != rd->relocs.end();
+ ++p)
+ {
+ target->scan_relocs(options, symtab, this, p->sh_type,
+ p->contents->data(), p->reloc_count,
+ this->local_symbol_count_,
+ local_symbols,
+ this->symbols_);
+ delete p->contents;
+ p->contents = NULL;
+ }
+
+ if (rd->local_symbols != NULL)
+ {
+ delete rd->local_symbols;
+ rd->local_symbols = NULL;
+ }
+}
+
// Relocate the input sections and write out the local symbols.
template<int size, bool big_endian>
void
-Sized_object<size, big_endian>::do_relocate(const General_options&,
+Sized_object<size, big_endian>::do_relocate(const General_options& options,
const Symbol_table* symtab,
- const Stringpool* sympool,
+ const Layout* layout,
Output_file* of)
{
unsigned int shnum = this->shnum();
@@ -78,7 +295,7 @@ Sized_object<size, big_endian>::do_relocate(const General_options&,
// Apply relocations.
- this->relocate_sections(symtab, pshdrs, &views);
+ this->relocate_sections(options, symtab, layout, pshdrs, &views);
// Write out the accumulated views.
for (unsigned int i = 1; i < shnum; ++i)
@@ -89,7 +306,7 @@ Sized_object<size, big_endian>::do_relocate(const General_options&,
}
// Write out the local symbols.
- this->write_local_symbols(of, sympool);
+ this->write_local_symbols(of, layout->sympool());
}
// Write section data to the output file. PSHDRS points to the
@@ -127,9 +344,8 @@ Sized_object<size, big_endian>::write_sections(const unsigned char* pshdrs,
off_t sh_size = shdr.get_sh_size();
unsigned char* view = of->get_output_view(start, sh_size);
- this->input_file()->file().read(shdr.get_sh_offset(),
- sh_size,
- view);
+ this->read(shdr.get_sh_offset(), sh_size, view);
+
pvs->view = view;
pvs->address = os->address() + map_sections[i].offset;
pvs->offset = start;
@@ -142,14 +358,25 @@ Sized_object<size, big_endian>::write_sections(const unsigned char* pshdrs,
template<int size, bool big_endian>
void
-Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab,
- const unsigned char* pshdrs,
- Views* pviews)
+Sized_object<size, big_endian>::relocate_sections(
+ const General_options& options,
+ const Symbol_table* symtab,
+ const Layout* layout,
+ const unsigned char* pshdrs,
+ Views* pviews)
{
unsigned int shnum = this->shnum();
- std::vector<Map_to_output>& map_sections(this->map_to_output());
Sized_target<size, big_endian>* target = this->sized_target();
+ Relocate_info<size, big_endian> relinfo;
+ relinfo.options = &options;
+ relinfo.symtab = symtab;
+ relinfo.layout = layout;
+ relinfo.object = this;
+ relinfo.local_symbol_count = this->local_symbol_count_;
+ relinfo.values = this->values_;
+ relinfo.symbols = this->symbols_;
+
const unsigned char* p = pshdrs + This::shdr_size;
for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
{
@@ -167,7 +394,7 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab,
gold_exit(false);
}
- if (map_sections[index].output_section == NULL)
+ if (!this->is_section_included(index))
{
// This relocation section is against a section which we
// discarded.
@@ -215,10 +442,12 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab,
gold_exit(false);
}
- target->relocate_section(symtab, this, sh_type, prelocs, reloc_count,
- this->local_symbol_count_,
- this->values_,
- this->symbols_,
+ relinfo.reloc_shndx = i;
+ relinfo.data_shndx = index;
+ target->relocate_section(&relinfo,
+ sh_type,
+ prelocs,
+ reloc_count,
(*pviews)[index].view,
(*pviews)[index].address,
(*pviews)[index].view_size);
@@ -230,30 +459,70 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab,
template
void
+Sized_object<32, false>::do_read_relocs(Read_relocs_data* rd);
+
+template
+void
+Sized_object<32, true>::do_read_relocs(Read_relocs_data* rd);
+
+template
+void
+Sized_object<64, false>::do_read_relocs(Read_relocs_data* rd);
+
+template
+void
+Sized_object<64, true>::do_read_relocs(Read_relocs_data* rd);
+
+template
+void
+Sized_object<32, false>::do_scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Read_relocs_data* rd);
+
+template
+void
+Sized_object<32, true>::do_scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Read_relocs_data* rd);
+
+template
+void
+Sized_object<64, false>::do_scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Read_relocs_data* rd);
+
+template
+void
+Sized_object<64, true>::do_scan_relocs(const General_options& options,
+ Symbol_table* symtab,
+ Read_relocs_data* rd);
+
+template
+void
Sized_object<32, false>::do_relocate(const General_options& options,
const Symbol_table* symtab,
- const Stringpool* sympool,
+ const Layout* layout,
Output_file* of);
template
void
Sized_object<32, true>::do_relocate(const General_options& options,
const Symbol_table* symtab,
- const Stringpool* sympool,
+ const Layout* layout,
Output_file* of);
template
void
Sized_object<64, false>::do_relocate(const General_options& options,
const Symbol_table* symtab,
- const Stringpool* sympool,
+ const Layout* layout,
Output_file* of);
template
void
Sized_object<64, true>::do_relocate(const General_options& options,
const Symbol_table* symtab,
- const Stringpool* sympool,
+ const Layout* layout,
Output_file* of);