X-Git-Url: https://oss.titaniummirror.com/gitweb?p=msp430-binutils.git;a=blobdiff_plain;f=gold%2Fcopy-relocs.cc;fp=gold%2Fcopy-relocs.cc;h=6ef72d3ed38677ca903142989e4ba28c5cd6ee4b;hp=0000000000000000000000000000000000000000;hb=88750007d7869f178f0ba528f41efd3b74c424cf;hpb=6df9443a374e2b81278c61b8afc0a1eef7db280b diff --git a/gold/copy-relocs.cc b/gold/copy-relocs.cc new file mode 100644 index 0000000..6ef72d3 --- /dev/null +++ b/gold/copy-relocs.cc @@ -0,0 +1,244 @@ +// copy-relocs.cc -- handle COPY relocations for gold. + +// Copyright 2006, 2007, 2008 Free Software Foundation, Inc. +// Written by Ian Lance Taylor . + +// This file is part of gold. + +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation; either version 3 of the License, or +// (at your option) any later version. + +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, +// MA 02110-1301, USA. + +#include "gold.h" + +#include "symtab.h" +#include "copy-relocs.h" + +namespace gold +{ + +// Copy_relocs::Copy_reloc_entry methods. + +// Emit the reloc if appropriate. + +template +void +Copy_relocs::Copy_reloc_entry::emit( + Output_data_reloc* reloc_section) +{ + // If the symbol is no longer defined in a dynamic object, then we + // emitted a COPY relocation, and we do not want to emit this + // dynamic relocation. + if (this->sym_->is_from_dynobj()) + reloc_section->add_global(this->sym_, this->reloc_type_, + this->output_section_, this->relobj_, + this->shndx_, this->address_, + this->addend_); +} + +// Copy_relocs methods. + +// Handle a relocation against a symbol which may force us to generate +// a COPY reloc. + +template +void +Copy_relocs::copy_reloc( + Symbol_table* symtab, + Layout* layout, + Sized_symbol* sym, + Sized_relobj* object, + unsigned int shndx, + Output_section *output_section, + const Reloc& rel, + Output_data_reloc* reloc_section) +{ + if (this->need_copy_reloc(sym, object, shndx)) + this->emit_copy_reloc(symtab, layout, sym, reloc_section); + else + { + // We may not need a COPY relocation. Save this relocation to + // possibly be emitted later. + this->save(sym, object, shndx, output_section, rel); + } +} + +// Return whether we need a COPY reloc for a relocation against SYM. +// The relocation is begin applied to section SHNDX in OBJECT. + +template +bool +Copy_relocs::need_copy_reloc( + Sized_symbol* sym, + Sized_relobj* object, + unsigned int shndx) const +{ + if (!parameters->options().copyreloc()) + return false; + + if (sym->symsize() == 0) + return false; + + // If this is a readonly section, then we need a COPY reloc. + // Otherwise we can use a dynamic reloc. Note that calling + // section_flags here can be slow, as the information is not cached; + // fortunately we shouldn't see too many potential COPY relocs. + if ((object->section_flags(shndx) & elfcpp::SHF_WRITE) == 0) + return true; + + return false; +} + +// Emit a COPY relocation for SYM. + +template +void +Copy_relocs::emit_copy_reloc( + Symbol_table* symtab, + Layout* layout, + Sized_symbol* sym, + Output_data_reloc* reloc_section) +{ + // We should not be here if -z nocopyreloc is given. + gold_assert(parameters->options().copyreloc()); + + typename elfcpp::Elf_types::Elf_WXword symsize = sym->symsize(); + + // There is no defined way to determine the required alignment of + // the symbol. We know that the symbol is defined in a dynamic + // object. We start with the alignment of the section in which it + // is defined; presumably we do not require an alignment larger than + // that. Then we reduce that alignment if the symbol is not aligned + // within the section. + gold_assert(sym->is_from_dynobj()); + bool is_ordinary; + unsigned int shndx = sym->shndx(&is_ordinary); + gold_assert(is_ordinary); + typename elfcpp::Elf_types::Elf_WXword addralign = + sym->object()->section_addralign(shndx); + + typename Sized_symbol::Value_type value = sym->value(); + while ((value & (addralign - 1)) != 0) + addralign >>= 1; + + if (this->dynbss_ == NULL) + { + this->dynbss_ = new Output_data_space(addralign, "** dynbss"); + layout->add_output_section_data(".bss", + elfcpp::SHT_NOBITS, + elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, + this->dynbss_); + } + + Output_data_space* dynbss = this->dynbss_; + + if (addralign > dynbss->addralign()) + dynbss->set_space_alignment(addralign); + + section_size_type dynbss_size = + convert_to_section_size_type(dynbss->current_data_size()); + dynbss_size = align_address(dynbss_size, addralign); + section_size_type offset = dynbss_size; + dynbss->set_current_data_size(dynbss_size + symsize); + + // Define the symbol as being copied. + symtab->define_with_copy_reloc(sym, dynbss, offset); + + // Add the COPY relocation to the dynamic reloc section. + this->add_copy_reloc(sym, offset, reloc_section); +} + +// Add a COPY relocation for SYM to RELOC_SECTION. + +template +void +Copy_relocs::add_copy_reloc( + Symbol* sym, + section_size_type offset, + Output_data_reloc* reloc_section) +{ + reloc_section->add_global(sym, this->copy_reloc_type_, this->dynbss_, + offset, 0); +} + +// Save a relocation to possibly be emitted later. + +template +void +Copy_relocs::save( + Symbol* sym, + Sized_relobj* object, + unsigned int shndx, + Output_section* output_section, + const Reloc& rel) +{ + unsigned int reloc_type = elfcpp::elf_r_type(rel.get_r_info()); + typename elfcpp::Elf_types::Elf_Addr addend = + Reloc_types::get_reloc_addend_noerror(&rel); + this->entries_.push_back(Copy_reloc_entry(sym, reloc_type, object, shndx, + output_section, rel.get_r_offset(), + addend)); +} + +// Emit any saved relocs. + +template +void +Copy_relocs::emit( + Output_data_reloc* reloc_section) +{ + for (typename Copy_reloc_entries::iterator p = this->entries_.begin(); + p != this->entries_.end(); + ++p) + p->emit(reloc_section); + + // We no longer need the saved information. + this->entries_.clear(); +} + +// Instantiate the templates we need. + +#ifdef HAVE_TARGET_32_LITTLE +template +class Copy_relocs; + +template +class Copy_relocs; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Copy_relocs; + +template +class Copy_relocs; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Copy_relocs; + +template +class Copy_relocs; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Copy_relocs; + +template +class Copy_relocs; +#endif + +} // End namespace gold.