diff options
Diffstat (limited to 'gold/object.cc')
| -rw-r--r-- | gold/object.cc | 158 |
1 files changed, 129 insertions, 29 deletions
diff --git a/gold/object.cc b/gold/object.cc index 1b964d7..b72fb58 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -914,14 +914,15 @@ Sized_relobj<size, big_endian>::layout_section(Layout* layout, // whether they should be included in the link. If they should, we // pass them to the Layout object, which will return an output section // and an offset. -// During garbage collection (gc-sections), this function is called -// twice. When it is called the first time, it is for setting up some -// sections as roots to a work-list and to do comdat processing. Actual -// layout happens the second time around after all the relevant sections -// have been determined. The first time, is_worklist_ready is false. -// It is then set to true after the worklist is processed and the relevant -// sections are determined. Then, this function is called again to -// layout the sections. +// During garbage collection (--gc-sections) and identical code folding +// (--icf), this function is called twice. When it is called the first +// time, it is for setting up some sections as roots to a work-list for +// --gc-sections and to do comdat processing. Actual layout happens the +// second time around after all the relevant sections have been determined. +// The first time, is_worklist_ready or is_icf_ready is false. It is then +// set to true after the garbage collection worklist or identical code +// folding is processed and the relevant sections to be kept are +// determined. Then, this function is called again to layout the sections. template<int size, bool big_endian> void @@ -930,10 +931,22 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, Read_symbols_data* sd) { const unsigned int shnum = this->shnum(); - bool is_gc_pass_one = (parameters->options().gc_sections() - && !symtab->gc()->is_worklist_ready()); - bool is_gc_pass_two = (parameters->options().gc_sections() - && symtab->gc()->is_worklist_ready()); + bool is_gc_pass_one = ((parameters->options().gc_sections() + && !symtab->gc()->is_worklist_ready()) + || (parameters->options().icf() + && !symtab->icf()->is_icf_ready())); + + bool is_gc_pass_two = ((parameters->options().gc_sections() + && symtab->gc()->is_worklist_ready()) + || (parameters->options().icf() + && symtab->icf()->is_icf_ready())); + + bool is_gc_or_icf = (parameters->options().gc_sections() + || parameters->options().icf()); + + // Both is_gc_pass_one and is_gc_pass_two should not be true. + gold_assert(!(is_gc_pass_one && is_gc_pass_two)); + if (shnum == 0) return; Symbols_data* gc_sd = NULL; @@ -958,7 +971,7 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, const unsigned char* symbol_names_data = NULL; section_size_type symbol_names_size; - if (parameters->options().gc_sections()) + if (is_gc_or_icf) { section_headers_data = gc_sd->section_headers_data; section_names_size = gc_sd->section_names_size; @@ -986,9 +999,10 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, const unsigned char* pshdrs; // Get the section names. - const unsigned char* pnamesu = parameters->options().gc_sections() ? - gc_sd->section_names_data : - sd->section_names->data(); + const unsigned char* pnamesu = (is_gc_or_icf) + ? gc_sd->section_names_data + : sd->section_names->data(); + const char* pnames = reinterpret_cast<const char*>(pnamesu); // If any input files have been claimed by plugins, we need to defer @@ -1141,7 +1155,7 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, } } - if (is_gc_pass_one) + if (is_gc_pass_one && parameters->options().gc_sections()) { if (is_section_name_included(name) || shdr.get_sh_type() == elfcpp::SHT_INIT_ARRAY @@ -1188,7 +1202,7 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, continue; } - if (is_gc_pass_two) + if (is_gc_pass_two && parameters->options().gc_sections()) { // This is executed during the second pass of garbage // collection. do_layout has been called before and some @@ -1199,13 +1213,12 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, gold_assert(out_section_offsets[i] == invalid_address); continue; } - if ((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0) - if (symtab->gc()->referenced_list().find(Section_id(this,i)) - == symtab->gc()->referenced_list().end()) + if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0) + && symtab->gc()->is_section_garbage(this, i)) { if (parameters->options().print_gc_sections()) gold_info(_("%s: removing unused section from '%s'" - " in file '%s"), + " in file '%s'"), program_name, this->section_name(i).c_str(), this->name().c_str()); out_sections[i] = NULL; @@ -1213,6 +1226,36 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, continue; } } + + if (is_gc_pass_two && parameters->options().icf()) + { + if (out_sections[i] == NULL) + { + gold_assert(out_section_offsets[i] == invalid_address); + continue; + } + if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0) + && symtab->icf()->is_section_folded(this, i)) + { + if (parameters->options().print_icf_sections()) + { + Section_id folded = + symtab->icf()->get_folded_section(this, i); + Relobj* folded_obj = + reinterpret_cast<Relobj*>(folded.first); + gold_info(_("%s: ICF folding section '%s' in file '%s'" + "into '%s' in file '%s'"), + program_name, this->section_name(i).c_str(), + this->name().c_str(), + folded_obj->section_name(folded.second).c_str(), + folded_obj->name().c_str()); + } + out_sections[i] = NULL; + out_section_offsets[i] = invalid_address; + continue; + } + } + // Defer layout here if input files are claimed by plugins. When gc // is turned on this function is called twice. For the second call // should_defer_layout should be false. @@ -1228,7 +1271,8 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, out_sections[i] = reinterpret_cast<Output_section*>(2); out_section_offsets[i] = invalid_address; continue; - } + } + // During gc_pass_two if a section that was previously deferred is // found, do not layout the section as layout_deferred_sections will // do it later from gold.cc. @@ -1256,10 +1300,13 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, layout->layout_gnu_stack(seen_gnu_stack, gnu_stack_flags); // When doing a relocatable link handle the reloc sections at the - // end. Garbage collection is not turned on for relocatable code. + // end. Garbage collection and Identical Code Folding is not + // turned on for relocatable code. if (emit_relocs) this->size_relocatable_relocs(); - gold_assert(!parameters->options().gc_sections() || reloc_sections.empty()); + + gold_assert(!(is_gc_or_icf) || reloc_sections.empty()); + for (std::vector<unsigned int>::const_iterator p = reloc_sections.begin(); p != reloc_sections.end(); ++p) @@ -1342,6 +1389,7 @@ Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab, delete[] gc_sd->section_names_data; delete[] gc_sd->symbols_data; delete[] gc_sd->symbol_names_data; + this->set_symbols_data(NULL); } else { @@ -1554,7 +1602,8 @@ Sized_relobj<size, big_endian>::do_count_local_symbols(Stringpool* pool, template<int size, bool big_endian> unsigned int Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index, - off_t off) + off_t off, + Symbol_table* symtab) { gold_assert(off == static_cast<off_t>(align_address(off, size >> 3))); @@ -1596,6 +1645,21 @@ Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index, } Output_section* os = out_sections[shndx]; + Address secoffset = out_offsets[shndx]; + if (symtab->is_section_folded(this, shndx)) + { + gold_assert (os == NULL && secoffset == invalid_address); + // Get the os of the section it is folded onto. + Section_id folded = symtab->icf()->get_folded_section(this, + shndx); + gold_assert(folded.first != NULL); + Sized_relobj<size, big_endian>* folded_obj = reinterpret_cast + <Sized_relobj<size, big_endian>*>(folded.first); + os = folded_obj->output_section(folded.second); + gold_assert(os != NULL); + secoffset = folded_obj->get_output_section_offset(folded.second); + gold_assert(secoffset != invalid_address); + } if (os == NULL) { @@ -1605,7 +1669,7 @@ Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index, // so we leave the input value unchanged here. continue; } - else if (out_offsets[shndx] == invalid_address) + else if (secoffset == invalid_address) { uint64_t start; @@ -1647,11 +1711,11 @@ Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index, } else if (lv.is_tls_symbol()) lv.set_output_value(os->tls_offset() - + out_offsets[shndx] + + secoffset + lv.input_value()); else lv.set_output_value((relocatable ? 0 : os->address()) - + out_offsets[shndx] + + secoffset + lv.input_value()); } @@ -1696,6 +1760,42 @@ Sized_relobj<size, big_endian>::do_set_local_dynsym_offset(off_t off) return this->output_local_dynsym_count_; } +// If Symbols_data is not NULL get the section flags from here otherwise +// get it from the file. + +template<int size, bool big_endian> +uint64_t +Sized_relobj<size, big_endian>::do_section_flags(unsigned int shndx) +{ + Symbols_data* sd = this->get_symbols_data(); + if (sd != NULL) + { + const unsigned char* pshdrs = sd->section_headers_data + + This::shdr_size * shndx; + typename This::Shdr shdr(pshdrs); + return shdr.get_sh_flags(); + } + // If sd is NULL, read the section header from the file. + return this->elf_file_.section_flags(shndx); +} + +// Get the section's ent size from Symbols_data. Called by get_section_contents +// in icf.cc + +template<int size, bool big_endian> +uint64_t +Sized_relobj<size, big_endian>::do_section_entsize(unsigned int shndx) +{ + Symbols_data* sd = this->get_symbols_data(); + gold_assert (sd != NULL); + + const unsigned char* pshdrs = sd->section_headers_data + + This::shdr_size * shndx; + typename This::Shdr shdr(pshdrs); + return shdr.get_sh_entsize(); +} + + // Write out the local symbols. template<int size, bool big_endian> |