From 7bf1f8020f64a69dc0d93a166c96547655c7eeb2 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Thu, 6 Dec 2007 05:55:50 +0000 Subject: From Cary Coutant: More support for generating shared libraries. --- gold/i386.cc | 230 +++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 127 insertions(+), 103 deletions(-) (limited to 'gold/i386.cc') diff --git a/gold/i386.cc b/gold/i386.cc index 1bfc659..071940b 100644 --- a/gold/i386.cc +++ b/gold/i386.cc @@ -792,7 +792,7 @@ Target_i386::Scan::local(const General_options&, Output_section* output_section, const elfcpp::Rel<32, false>& reloc, unsigned int r_type, - const elfcpp::Sym<32, false>&) + const elfcpp::Sym<32, false>& lsym) { switch (r_type) { @@ -856,13 +856,12 @@ Target_i386::Scan::local(const General_options&, if (got->add_local(object, r_sym)) { // If we are generating a shared object, we need to add a - // dynamic RELATIVE relocation for this symbol. + // dynamic RELATIVE relocation for this symbol's GOT entry. if (parameters->output_is_position_independent()) { Reloc_section* rel_dyn = target->rel_dyn_section(layout); rel_dyn->add_local(object, 0, elfcpp::R_386_RELATIVE, - output_section, data_shndx, - reloc.get_r_offset()); + got, object->local_got_offset(r_sym)); } } } @@ -909,18 +908,10 @@ Target_i386::Scan::local(const General_options&, Output_data_got<32, false>* got = target->got_section(symtab, layout); unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - if (got->add_local_tls(object, r_sym, true)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off - = object->local_tls_got_offset(r_sym, true); - rel_dyn->add_local(object, r_sym, - elfcpp::R_386_TLS_DTPMOD32, - got, got_off); - rel_dyn->add_local(object, r_sym, - elfcpp::R_386_TLS_DTPOFF32, - got, got_off + 4); - } + got->add_local_tls_with_rel(object, r_sym, + lsym.get_st_shndx(), true, + target->rel_dyn_section(layout), + elfcpp::R_386_TLS_DTPMOD32); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_local(object, r_type); @@ -928,7 +919,10 @@ Target_i386::Scan::local(const General_options&, case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva) case elfcpp::R_386_TLS_DESC_CALL: - unsupported_reloc_local(object, r_type); + // FIXME: If not relaxing to LE, we need to generate + // a GOT entry with an R_386_TLS_DESC reloc. + if (optimized_type != tls::TLSOPT_TO_LE) + unsupported_reloc_local(object, r_type); break; case elfcpp::R_386_TLS_LDM: // Local-dynamic @@ -938,15 +932,10 @@ Target_i386::Scan::local(const General_options&, Output_data_got<32, false>* got = target->got_section(symtab, layout); unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - if (got->add_local_tls(object, r_sym, false)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off - = object->local_tls_got_offset(r_sym, false); - rel_dyn->add_local(object, r_sym, - elfcpp::R_386_TLS_DTPMOD32, got, - got_off); - } + got->add_local_tls_with_rel(object, r_sym, + lsym.get_st_shndx(), false, + target->rel_dyn_section(layout), + elfcpp::R_386_TLS_DTPMOD32); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_local(object, r_type); @@ -960,21 +949,26 @@ Target_i386::Scan::local(const General_options&, case elfcpp::R_386_TLS_GOTIE: if (optimized_type == tls::TLSOPT_NONE) { + // For the R_386_TLS_IE relocation, we need to create a + // dynamic relocation when building a shared library. + if (r_type == elfcpp::R_386_TLS_IE + && parameters->output_is_shared()) + { + Reloc_section* rel_dyn = target->rel_dyn_section(layout); + rel_dyn->add_local(object, 0, elfcpp::R_386_RELATIVE, + output_section, data_shndx, + reloc.get_r_offset()); + } // Create a GOT entry for the tp-relative offset. Output_data_got<32, false>* got = target->got_section(symtab, layout); unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); - if (got->add_local(object, r_sym)) - { - unsigned int dyn_r_type - = (r_type == elfcpp::R_386_TLS_IE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off = object->local_got_offset(r_sym); - rel_dyn->add_local(object, r_sym, dyn_r_type, got, - got_off); - } + unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32 + ? elfcpp::R_386_TLS_TPOFF32 + : elfcpp::R_386_TLS_TPOFF); + got->add_local_with_rel(object, r_sym, + target->rel_dyn_section(layout), + dyn_r_type); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_local(object, r_type); @@ -983,7 +977,16 @@ Target_i386::Scan::local(const General_options&, case elfcpp::R_386_TLS_LE: // Local-exec case elfcpp::R_386_TLS_LE_32: if (output_is_shared) - unsupported_reloc_local(object, r_type); + { + // We need to create a dynamic relocation. + unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info()); + unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32 + ? elfcpp::R_386_TLS_TPOFF32 + : elfcpp::R_386_TLS_TPOFF); + Reloc_section* rel_dyn = target->rel_dyn_section(layout); + rel_dyn->add_local(object, r_sym, dyn_r_type, output_section, + data_shndx, reloc.get_r_offset()); + } break; default: @@ -1087,7 +1090,17 @@ Target_i386::Scan::global(const General_options& options, { // Make a PLT entry if necessary. if (gsym->needs_plt_entry()) - target->make_plt_entry(symtab, layout, gsym); + { + // These relocations are used for function calls only in + // non-PIC code. For a 32-bit relocation in a shared library, + // we'll need a text relocation anyway, so we can skip the + // PLT entry and let the dynamic linker bind the call directly + // to the target. For smaller relocations, we should use a + // PLT entry to ensure that the call can reach. + if (!parameters->output_is_shared() + || r_type != elfcpp::R_386_PC32) + target->make_plt_entry(symtab, layout, gsym); + } // Make a dynamic relocation if necessary. bool is_function_call = (gsym->type() == elfcpp::STT_FUNC); if (gsym->needs_dynamic_reloc(false, is_function_call)) @@ -1111,18 +1124,18 @@ Target_i386::Scan::global(const General_options& options, { // The symbol requires a GOT entry. Output_data_got<32, false>* got = target->got_section(symtab, layout); - if (got->add_global(gsym)) - { + if (gsym->final_value_is_known()) + got->add_global(gsym); + else + { // If this symbol is not fully resolved, we need to add a - // dynamic relocation for it. - if (!gsym->final_value_is_known()) + // GOT entry with a dynamic relocation. + Reloc_section* rel_dyn = target->rel_dyn_section(layout); + if (gsym->is_from_dynobj() || gsym->is_preemptible()) + got->add_global_with_rel(gsym, rel_dyn, elfcpp::R_386_GLOB_DAT); + else { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - if (gsym->is_from_dynobj() - || gsym->is_preemptible()) - rel_dyn->add_global(gsym, elfcpp::R_386_GLOB_DAT, got, - gsym->got_offset()); - else + if (got->add_global(gsym)) { rel_dyn->add_local(object, 0, elfcpp::R_386_RELATIVE, got, gsym->got_offset()); @@ -1195,28 +1208,18 @@ Target_i386::Scan::global(const General_options& options, // dtv-relative offset. Output_data_got<32, false>* got = target->got_section(symtab, layout); - if (got->add_global_tls(gsym, true)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off = gsym->tls_got_offset(true); - rel_dyn->add_global(gsym, elfcpp::R_386_TLS_DTPMOD32, - got, got_off); - rel_dyn->add_global(gsym, elfcpp::R_386_TLS_DTPOFF32, - got, got_off + 4); - } + got->add_global_tls_with_rel(gsym, + target->rel_dyn_section(layout), + elfcpp::R_386_TLS_DTPMOD32, + elfcpp::R_386_TLS_DTPOFF32); } else if (optimized_type == tls::TLSOPT_TO_IE) { // Create a GOT entry for the tp-relative offset. Output_data_got<32, false>* got = target->got_section(symtab, layout); - if (got->add_global(gsym)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off = gsym->got_offset(); - rel_dyn->add_global(gsym, elfcpp::R_386_TLS_TPOFF32, - got, got_off); - } + got->add_global_with_rel(gsym, target->rel_dyn_section(layout), + elfcpp::R_386_TLS_TPOFF32); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_global(object, r_type, gsym); @@ -1224,6 +1227,10 @@ Target_i386::Scan::global(const General_options& options, case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url) case elfcpp::R_386_TLS_DESC_CALL: + // FIXME: If not relaxing to LE, we need to generate + // a GOT entry with an R_386_TLS_DESC reloc. + if (optimized_type != tls::TLSOPT_TO_LE) + unsupported_reloc_global(object, r_type, gsym); unsupported_reloc_global(object, r_type, gsym); break; @@ -1235,13 +1242,9 @@ Target_i386::Scan::global(const General_options& options, // Create a GOT entry for the module index. Output_data_got<32, false>* got = target->got_section(symtab, layout); - if (got->add_global_tls(gsym, false)) - { - Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off = gsym->tls_got_offset(false); - rel_dyn->add_global(gsym, elfcpp::R_386_TLS_DTPMOD32, - got, got_off); - } + got->add_global_tls_with_rel(gsym, + target->rel_dyn_section(layout), + elfcpp::R_386_TLS_DTPMOD32); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_global(object, r_type, gsym); @@ -1255,19 +1258,25 @@ Target_i386::Scan::global(const General_options& options, case elfcpp::R_386_TLS_GOTIE: if (optimized_type == tls::TLSOPT_NONE) { - // Create a GOT entry for the tp-relative offset. - Output_data_got<32, false>* got - = target->got_section(symtab, layout); - if (got->add_global(gsym)) + // For the R_386_TLS_IE relocation, we need to create a + // dynamic relocation when building a shared library. + if (r_type == elfcpp::R_386_TLS_IE + && parameters->output_is_shared()) { - unsigned int dyn_r_type - = (r_type == elfcpp::R_386_TLS_IE_32 - ? elfcpp::R_386_TLS_TPOFF32 - : elfcpp::R_386_TLS_TPOFF); Reloc_section* rel_dyn = target->rel_dyn_section(layout); - unsigned int got_off = gsym->got_offset(); - rel_dyn->add_global(gsym, dyn_r_type, got, got_off); + rel_dyn->add_local(object, 0, elfcpp::R_386_RELATIVE, + output_section, data_shndx, + reloc.get_r_offset()); } + // Create a GOT entry for the tp-relative offset. + Output_data_got<32, false>* got + = target->got_section(symtab, layout); + unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32 + ? elfcpp::R_386_TLS_TPOFF32 + : elfcpp::R_386_TLS_TPOFF); + got->add_global_with_rel(gsym, + target->rel_dyn_section(layout), + dyn_r_type); } else if (optimized_type != tls::TLSOPT_TO_LE) unsupported_reloc_global(object, r_type, gsym); @@ -1276,7 +1285,15 @@ Target_i386::Scan::global(const General_options& options, case elfcpp::R_386_TLS_LE: // Local-exec case elfcpp::R_386_TLS_LE_32: if (parameters->output_is_shared()) - unsupported_reloc_global(object, r_type, gsym); + { + // We need to create a dynamic relocation. + unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32 + ? elfcpp::R_386_TLS_TPOFF32 + : elfcpp::R_386_TLS_TPOFF); + Reloc_section* rel_dyn = target->rel_dyn_section(layout); + rel_dyn->add_global(gsym, dyn_r_type, output_section, object, + data_shndx, reloc.get_r_offset()); + } break; default: @@ -1670,9 +1687,8 @@ Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo, if (optimized_type == tls::TLSOPT_TO_IE) { gold_assert(tls_segment != NULL); - this->tls_gd_to_ie(relinfo, relnum, tls_segment, - rel, r_type, got_offset, view, - view_size); + this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type, + got_offset, view, view_size); break; } else if (optimized_type == tls::TLSOPT_NONE) @@ -1741,13 +1757,11 @@ Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo, // won't see the TLS_LDM reloc. The local_dynamic_type field // tells us this. gold_assert(tls_segment != NULL); - if (optimized_type != tls::TLSOPT_TO_LE - || this->local_dynamic_type_ == LOCAL_DYNAMIC_NONE) - value = value - tls_segment->vaddr(); - else if (this->local_dynamic_type_ == LOCAL_DYNAMIC_GNU) - value = value - (tls_segment->vaddr() + tls_segment->memsz()); - else - value = tls_segment->vaddr() + tls_segment->memsz() - value; + if (this->local_dynamic_type_ == LOCAL_DYNAMIC_GNU) + value -= tls_segment->memsz(); + else if (optimized_type == tls::TLSOPT_TO_LE + && this->local_dynamic_type_ != LOCAL_DYNAMIC_NONE) + value = tls_segment->memsz() - value; Relocate_functions<32, false>::rel32(view, value); break; @@ -1793,15 +1807,25 @@ Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo, break; case elfcpp::R_386_TLS_LE: // Local-exec - gold_assert(tls_segment != NULL); - value = value - (tls_segment->vaddr() + tls_segment->memsz()); - Relocate_functions<32, false>::rel32(view, value); + // If we're creating a shared library, a dynamic relocation will + // have been created for this location, so do not apply it now. + if (!parameters->output_is_shared()) + { + gold_assert(tls_segment != NULL); + value -= tls_segment->memsz(); + Relocate_functions<32, false>::rel32(view, value); + } break; case elfcpp::R_386_TLS_LE_32: - gold_assert(tls_segment != NULL); - value = tls_segment->vaddr() + tls_segment->memsz() - value; - Relocate_functions<32, false>::rel32(view, value); + // If we're creating a shared library, a dynamic relocation will + // have been created for this location, so do not apply it now. + if (!parameters->output_is_shared()) + { + gold_assert(tls_segment != NULL); + value = tls_segment->memsz() - value; + Relocate_functions<32, false>::rel32(view, value); + } break; } } @@ -1862,7 +1886,7 @@ Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo, } } - value = tls_segment->vaddr() + tls_segment->memsz() - value; + value = tls_segment->memsz() - value; Relocate_functions<32, false>::rel32(view + roff, value); // The next reloc should be a PLT32 reloc against __tls_get_addr. @@ -1870,7 +1894,7 @@ Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo, this->skip_call_tls_get_addr_ = true; } -// Do a relocation in which we convert a TLS General-Dynamic to a +// Do a relocation in which we convert a TLS General-Dynamic to an // Initial-Exec. inline void @@ -1930,7 +1954,7 @@ Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo, } } - value = tls_segment->vaddr() + tls_segment->memsz() - value; + value = tls_segment->memsz() - value; Relocate_functions<32, false>::rel32(view + roff, value); // The next reloc should be a PLT32 reloc against __tls_get_addr. @@ -2059,7 +2083,7 @@ Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo, tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0); } - value = tls_segment->vaddr() + tls_segment->memsz() - value; + value = tls_segment->memsz() - value; if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE) value = - value; -- cgit v1.1