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// target.h -- target support for gold -*- C++ -*-
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// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
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// Free Software Foundation, Inc.
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// Written by Ian Lance Taylor <iant@google.com>.
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// This file is part of gold.
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or
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// (at your option) any later version.
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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// The abstract class Target is the interface for target specific
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// support. It defines abstract methods which each target must
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// implement. Typically there will be one target per processor, but
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// in some cases it may be necessary to have subclasses.
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// For speed and consistency we want to use inline functions to handle
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// relocation processing. So besides implementations of the abstract
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// methods, each target is expected to define a template
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// specialization of the relocation functions.
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#include "parameters.h"
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template<int size, bool big_endian>
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template<int size, bool big_endian>
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class Sized_relobj_file;
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class Relocatable_relocs;
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template<int size, bool big_endian>
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class Reloc_symbol_changes;
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class Output_data_got_base;
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struct Symbol_location;
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// The abstract class for target specific handling.
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// Return the bit size that this target implements. This should
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{ return this->pti_->size; }
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// Return whether this target is big-endian.
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{ return this->pti_->is_big_endian; }
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// Machine code to store in e_machine field of ELF header.
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{ return this->pti_->machine_code; }
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// Processor specific flags to store in e_flags field of ELF header.
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processor_specific_flags() const
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{ return this->processor_specific_flags_; }
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// Whether processor specific flags are set at least once.
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are_processor_specific_flags_set() const
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{ return this->are_processor_specific_flags_set_; }
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// Whether this target has a specific make_symbol function.
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has_make_symbol() const
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{ return this->pti_->has_make_symbol; }
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// Whether this target has a specific resolve function.
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{ return this->pti_->has_resolve; }
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// Whether this target has a specific code fill function.
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has_code_fill() const
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{ return this->pti_->has_code_fill; }
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// Return the default name of the dynamic linker.
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dynamic_linker() const
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{ return this->pti_->dynamic_linker; }
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// Return the default address to use for the text segment.
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default_text_segment_address() const
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{ return this->pti_->default_text_segment_address; }
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// Return the ABI specified page size.
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if (parameters->options().max_page_size() > 0)
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return parameters->options().max_page_size();
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return this->pti_->abi_pagesize;
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// Return the common page size used on actual systems.
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common_pagesize() const
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if (parameters->options().common_page_size() > 0)
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return std::min(parameters->options().common_page_size(),
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this->abi_pagesize());
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return std::min(this->pti_->common_pagesize,
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this->abi_pagesize());
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// Return whether PF_X segments must contain nothing but the contents of
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// SHF_EXECINSTR sections (no non-executable data, no headers).
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isolate_execinstr() const
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{ return this->pti_->isolate_execinstr; }
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rosegment_gap() const
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{ return this->pti_->rosegment_gap; }
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// If we see some object files with .note.GNU-stack sections, and
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// some objects files without them, this returns whether we should
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// consider the object files without them to imply that the stack
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// should be executable.
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is_default_stack_executable() const
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{ return this->pti_->is_default_stack_executable; }
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// Return a character which may appear as a prefix for a wrap
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// symbol. If this character appears, we strip it when checking for
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// wrapping and add it back when forming the final symbol name.
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// This should be '\0' if not special prefix is required, which is
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{ return this->pti_->wrap_char; }
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// Return the special section index which indicates a small common
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// symbol. This will return SHN_UNDEF if there are no small common
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small_common_shndx() const
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{ return this->pti_->small_common_shndx; }
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// Return values to add to the section flags for the section holding
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// small common symbols.
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small_common_section_flags() const
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gold_assert(this->pti_->small_common_shndx != elfcpp::SHN_UNDEF);
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return this->pti_->small_common_section_flags;
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// Return the special section index which indicates a large common
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// symbol. This will return SHN_UNDEF if there are no large common
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large_common_shndx() const
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{ return this->pti_->large_common_shndx; }
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// Return values to add to the section flags for the section holding
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// large common symbols.
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large_common_section_flags() const
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gold_assert(this->pti_->large_common_shndx != elfcpp::SHN_UNDEF);
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return this->pti_->large_common_section_flags;
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// This hook is called when an output section is created.
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new_output_section(Output_section* os) const
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{ this->do_new_output_section(os); }
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// This is called to tell the target to complete any sections it is
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// handling. After this all sections must have their final size.
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finalize_sections(Layout* layout, const Input_objects* input_objects,
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Symbol_table* symtab)
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{ return this->do_finalize_sections(layout, input_objects, symtab); }
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// Return the value to use for a global symbol which needs a special
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// value in the dynamic symbol table. This will only be called if
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// the backend first calls symbol->set_needs_dynsym_value().
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dynsym_value(const Symbol* sym) const
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{ return this->do_dynsym_value(sym); }
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// Return a string to use to fill out a code section. This is
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// basically one or more NOPS which must fill out the specified
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code_fill(section_size_type length) const
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{ return this->do_code_fill(length); }
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// Return whether SYM is known to be defined by the ABI. This is
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// used to avoid inappropriate warnings about undefined symbols.
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is_defined_by_abi(const Symbol* sym) const
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{ return this->do_is_defined_by_abi(sym); }
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// Adjust the output file header before it is written out. VIEW
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// points to the header in external form. LEN is the length.
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adjust_elf_header(unsigned char* view, int len) const
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{ return this->do_adjust_elf_header(view, len); }
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// Return address and size to plug into eh_frame FDEs associated with a PLT.
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plt_fde_location(const Output_data* plt, unsigned char* oview,
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uint64_t* address, off_t* len) const
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{ return this->do_plt_fde_location(plt, oview, address, len); }
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// Return whether NAME is a local label name. This is used to implement the
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// --discard-locals options.
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is_local_label_name(const char* name) const
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{ return this->do_is_local_label_name(name); }
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// Get the symbol index to use for a target specific reloc.
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reloc_symbol_index(void* arg, unsigned int type) const
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{ return this->do_reloc_symbol_index(arg, type); }
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// Get the addend to use for a target specific reloc.
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reloc_addend(void* arg, unsigned int type, uint64_t addend) const
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{ return this->do_reloc_addend(arg, type, addend); }
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// Return the PLT address to use for a global symbol.
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plt_address_for_global(const Symbol* sym) const
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{ return this->do_plt_address_for_global(sym); }
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// Return the PLT address to use for a local symbol.
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plt_address_for_local(const Relobj* object, unsigned int symndx) const
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{ return this->do_plt_address_for_local(object, symndx); }
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// Return the offset to use for the GOT_INDX'th got entry which is
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// for a local tls symbol specified by OBJECT, SYMNDX.
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tls_offset_for_local(const Relobj* object,
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unsigned int got_indx) const
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{ return do_tls_offset_for_local(object, symndx, got_indx); }
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// Return the offset to use for the GOT_INDX'th got entry which is
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// for global tls symbol GSYM.
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tls_offset_for_global(Symbol* gsym, unsigned int got_indx) const
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{ return do_tls_offset_for_global(gsym, got_indx); }
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// For targets that use function descriptors, if LOC is the location
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// of a function, modify it to point at the function entry location.
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function_location(Symbol_location* loc) const
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{ return do_function_location(loc); }
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// Return whether this target can use relocation types to determine
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// if a function's address is taken.
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can_check_for_function_pointers() const
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{ return this->do_can_check_for_function_pointers(); }
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// Return whether a relocation to a merged section can be processed
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// to retrieve the contents.
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can_icf_inline_merge_sections () const
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{ return this->pti_->can_icf_inline_merge_sections; }
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// Whether a section called SECTION_NAME may have function pointers to
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// sections not eligible for safe ICF folding.
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section_may_have_icf_unsafe_pointers(const char* section_name) const
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{ return this->do_section_may_have_icf_unsafe_pointers(section_name); }
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// Return the base to use for the PC value in an FDE when it is
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// encoded using DW_EH_PE_datarel. This does not appear to be
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// documented anywhere, but it is target specific. Any use of
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// DW_EH_PE_datarel in gcc requires defining a special macro
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// (ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX) to output the value.
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ehframe_datarel_base() const
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{ return this->do_ehframe_datarel_base(); }
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// Return true if a reference to SYM from a reloc of type R_TYPE
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// means that the current function may call an object compiled
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// without -fsplit-stack. SYM is known to be defined in an object
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// compiled without -fsplit-stack.
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is_call_to_non_split(const Symbol* sym, unsigned int r_type) const
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{ return this->do_is_call_to_non_split(sym, r_type); }
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// A function starts at OFFSET in section SHNDX in OBJECT. That
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// function was compiled with -fsplit-stack, but it refers to a
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// function which was compiled without -fsplit-stack. VIEW is a
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// modifiable view of the section; VIEW_SIZE is the size of the
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// view. The target has to adjust the function so that it allocates
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calls_non_split(Relobj* object, unsigned int shndx,
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section_offset_type fnoffset, section_size_type fnsize,
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unsigned char* view, section_size_type view_size,
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std::string* from, std::string* to) const
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this->do_calls_non_split(object, shndx, fnoffset, fnsize, view, view_size,
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// Make an ELF object.
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template<int size, bool big_endian>
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make_elf_object(const std::string& name, Input_file* input_file,
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off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
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{ return this->do_make_elf_object(name, input_file, offset, ehdr); }
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// Make an output section.
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make_output_section(const char* name, elfcpp::Elf_Word type,
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elfcpp::Elf_Xword flags)
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{ return this->do_make_output_section(name, type, flags); }
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// Return true if target wants to perform relaxation.
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// Run the dummy relaxation pass twice if relaxation debugging is enabled.
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if (is_debugging_enabled(DEBUG_RELAXATION))
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return this->do_may_relax();
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// Perform a relaxation pass. Return true if layout may be changed.
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relax(int pass, const Input_objects* input_objects, Symbol_table* symtab,
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Layout* layout, const Task* task)
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// Run the dummy relaxation pass twice if relaxation debugging is enabled.
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if (is_debugging_enabled(DEBUG_RELAXATION))
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return this->do_relax(pass, input_objects, symtab, layout, task);
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// Return the target-specific name of attributes section. This is
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// NULL if a target does not use attributes section or if it uses
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// the default section name ".gnu.attributes".
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attributes_section() const
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{ return this->pti_->attributes_section; }
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// Return the vendor name of vendor attributes.
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attributes_vendor() const
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{ return this->pti_->attributes_vendor; }
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// Whether a section called NAME is an attribute section.
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is_attributes_section(const char* name) const
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return ((this->pti_->attributes_section != NULL
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&& strcmp(name, this->pti_->attributes_section) == 0)
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|| strcmp(name, ".gnu.attributes") == 0);
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// Return a bit mask of argument types for attribute with TAG.
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attribute_arg_type(int tag) const
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{ return this->do_attribute_arg_type(tag); }
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// Return the attribute tag of the position NUM in the list of fixed
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// attributes. Normally there is no reordering and
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// attributes_order(NUM) == NUM.
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attributes_order(int num) const
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{ return this->do_attributes_order(num); }
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// When a target is selected as the default target, we call this method,
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// which may be used for expensive, target-specific initialization.
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select_as_default_target()
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{ this->do_select_as_default_target(); }
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// Return the value to store in the EI_OSABI field in the ELF
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{ return this->osabi_; }
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// Set the value to store in the EI_OSABI field in the ELF header.
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set_osabi(elfcpp::ELFOSABI osabi)
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{ this->osabi_ = osabi; }
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// Define target-specific standard symbols.
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define_standard_symbols(Symbol_table* symtab, Layout* layout)
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{ this->do_define_standard_symbols(symtab, layout); }
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// Return the output section name to use given an input section
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// name, or NULL if no target specific name mapping is required.
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// Set *PLEN to the length of the name if returning non-NULL.
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output_section_name(const Relobj* relobj,
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{ return this->do_output_section_name(relobj, name, plen); }
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// Add any special sections for this symbol to the gc work list.
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gc_mark_symbol(Symbol_table* symtab, Symbol* sym) const
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{ this->do_gc_mark_symbol(symtab, sym); }
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// This struct holds the constant information for a child class. We
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// use a struct to avoid the overhead of virtual function calls for
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// simple information.
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// Address size (32 or 64).
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// Whether the target is big endian.
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// The code to store in the e_machine field of the ELF header.
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elfcpp::EM machine_code;
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// Whether this target has a specific make_symbol function.
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bool has_make_symbol;
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// Whether this target has a specific resolve function.
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// Whether this target has a specific code fill function.
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// Whether an object file with no .note.GNU-stack sections implies
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// that the stack should be executable.
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bool is_default_stack_executable;
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// Whether a relocation to a merged section can be processed to
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// retrieve the contents.
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bool can_icf_inline_merge_sections;
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// Prefix character to strip when checking for wrapping.
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// The default dynamic linker name.
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const char* dynamic_linker;
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// The default text segment address.
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uint64_t default_text_segment_address;
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// The ABI specified page size.
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uint64_t abi_pagesize;
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// The common page size used by actual implementations.
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uint64_t common_pagesize;
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// Whether PF_X segments must contain nothing but the contents of
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// SHF_EXECINSTR sections (no non-executable data, no headers).
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bool isolate_execinstr;
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// If nonzero, distance from the text segment to the read-only segment.
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uint64_t rosegment_gap;
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// The special section index for small common symbols; SHN_UNDEF
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elfcpp::Elf_Half small_common_shndx;
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// The special section index for large common symbols; SHN_UNDEF
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elfcpp::Elf_Half large_common_shndx;
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// Section flags for small common section.
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elfcpp::Elf_Xword small_common_section_flags;
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// Section flags for large common section.
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elfcpp::Elf_Xword large_common_section_flags;
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// Name of attributes section if it is not ".gnu.attributes".
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const char* attributes_section;
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// Vendor name of vendor attributes.
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const char* attributes_vendor;
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Target(const Target_info* pti)
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: pti_(pti), processor_specific_flags_(0),
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are_processor_specific_flags_set_(false), osabi_(elfcpp::ELFOSABI_NONE)
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// Virtual function which may be implemented by the child class.
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do_new_output_section(Output_section*) const
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// Virtual function which may be implemented by the child class.
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do_finalize_sections(Layout*, const Input_objects*, Symbol_table*)
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// Virtual function which may be implemented by the child class.
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do_dynsym_value(const Symbol*) const
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{ gold_unreachable(); }
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// Virtual function which must be implemented by the child class if
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do_code_fill(section_size_type) const
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{ gold_unreachable(); }
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// Virtual function which may be implemented by the child class.
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do_is_defined_by_abi(const Symbol*) const
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// Adjust the output file header before it is written out. VIEW
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// points to the header in external form. LEN is the length, and
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// will be one of the values of elfcpp::Elf_sizes<size>::ehdr_size.
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// By default, we set the EI_OSABI field if requested (in
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do_adjust_elf_header(unsigned char*, int) const = 0;
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// Return address and size to plug into eh_frame FDEs associated with a PLT.
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do_plt_fde_location(const Output_data* plt, unsigned char* oview,
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uint64_t* address, off_t* len) const;
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// Virtual function which may be overridden by the child class.
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do_is_local_label_name(const char*) const;
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// Virtual function that must be overridden by a target which uses
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// target specific relocations.
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do_reloc_symbol_index(void*, unsigned int) const
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{ gold_unreachable(); }
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// Virtual function that must be overridden by a target which uses
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// target specific relocations.
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do_reloc_addend(void*, unsigned int, uint64_t) const
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{ gold_unreachable(); }
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// Virtual functions that must be overridden by a target that uses
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// STT_GNU_IFUNC symbols.
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do_plt_address_for_global(const Symbol*) const
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{ gold_unreachable(); }
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do_plt_address_for_local(const Relobj*, unsigned int) const
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{ gold_unreachable(); }
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do_tls_offset_for_local(const Relobj*, unsigned int, unsigned int) const
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{ gold_unreachable(); }
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do_tls_offset_for_global(Symbol*, unsigned int) const
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{ gold_unreachable(); }
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do_function_location(Symbol_location*) const = 0;
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// Virtual function which may be overriden by the child class.
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do_can_check_for_function_pointers() const
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// Virtual function which may be overridden by the child class. We
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// recognize some default sections for which we don't care whether
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// they have function pointers.
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do_section_may_have_icf_unsafe_pointers(const char* section_name) const
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// We recognize sections for normal vtables, construction vtables and
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return (!is_prefix_of(".rodata._ZTV", section_name)
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&& !is_prefix_of(".data.rel.ro._ZTV", section_name)
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&& !is_prefix_of(".rodata._ZTC", section_name)
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&& !is_prefix_of(".data.rel.ro._ZTC", section_name)
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&& !is_prefix_of(".eh_frame", section_name));
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do_ehframe_datarel_base() const
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{ gold_unreachable(); }
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// Virtual function which may be overridden by the child class. The
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// default implementation is that any function not defined by the
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// ABI is a call to a non-split function.
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do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
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// Virtual function which may be overridden by the child class.
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do_calls_non_split(Relobj* object, unsigned int, section_offset_type,
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section_size_type, unsigned char*, section_size_type,
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std::string*, std::string*) const;
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// make_elf_object hooks. There are four versions of these for
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// different address sizes and endianness.
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// Set processor specific flags.
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set_processor_specific_flags(elfcpp::Elf_Word flags)
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this->processor_specific_flags_ = flags;
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this->are_processor_specific_flags_set_ = true;
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#ifdef HAVE_TARGET_32_LITTLE
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// Virtual functions which may be overridden by the child class.
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do_make_elf_object(const std::string&, Input_file*, off_t,
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const elfcpp::Ehdr<32, false>&);
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#ifdef HAVE_TARGET_32_BIG
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// Virtual functions which may be overridden by the child class.
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do_make_elf_object(const std::string&, Input_file*, off_t,
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const elfcpp::Ehdr<32, true>&);
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#ifdef HAVE_TARGET_64_LITTLE
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// Virtual functions which may be overridden by the child class.
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do_make_elf_object(const std::string&, Input_file*, off_t,
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const elfcpp::Ehdr<64, false>& ehdr);
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#ifdef HAVE_TARGET_64_BIG
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// Virtual functions which may be overridden by the child class.
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do_make_elf_object(const std::string& name, Input_file* input_file,
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off_t offset, const elfcpp::Ehdr<64, true>& ehdr);
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// Virtual functions which may be overridden by the child class.
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virtual Output_section*
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do_make_output_section(const char* name, elfcpp::Elf_Word type,
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elfcpp::Elf_Xword flags);
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// Virtual function which may be overridden by the child class.
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{ return parameters->options().relax(); }
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// Virtual function which may be overridden by the child class.
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do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*)
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// A function for targets to call. Return whether BYTES/LEN matches
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// VIEW/VIEW_SIZE at OFFSET.
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match_view(const unsigned char* view, section_size_type view_size,
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section_offset_type offset, const char* bytes, size_t len) const;
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// Set the contents of a VIEW/VIEW_SIZE to nops starting at OFFSET
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set_view_to_nop(unsigned char* view, section_size_type view_size,
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section_offset_type offset, size_t len) const;
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// This must be overridden by the child class if it has target-specific
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// attributes subsection in the attribute section.
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do_attribute_arg_type(int) const
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{ gold_unreachable(); }
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// This may be overridden by the child class.
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do_attributes_order(int num) const
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// This may be overridden by the child class.
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do_select_as_default_target()
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// This may be overridden by the child class.
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do_define_standard_symbols(Symbol_table*, Layout*)
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// This may be overridden by the child class.
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do_output_section_name(const Relobj*, const char*, size_t*) const
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// This may be overridden by the child class.
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do_gc_mark_symbol(Symbol_table*, Symbol*) const
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// The implementations of the four do_make_elf_object virtual functions are
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// almost identical except for their sizes and endianness. We use a template.
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// for their implementations.
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template<int size, bool big_endian>
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do_make_elf_object_implementation(const std::string&, Input_file*, off_t,
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const elfcpp::Ehdr<size, big_endian>&);
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Target(const Target&);
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Target& operator=(const Target&);
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// The target information.
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const Target_info* pti_;
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// Processor-specific flags.
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elfcpp::Elf_Word processor_specific_flags_;
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// Whether the processor-specific flags are set at least once.
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bool are_processor_specific_flags_set_;
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// If not ELFOSABI_NONE, the value to put in the EI_OSABI field of
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// the ELF header. This is handled at this level because it is
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// OS-specific rather than processor-specific.
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elfcpp::ELFOSABI osabi_;
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// The abstract class for a specific size and endianness of target.
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// Each actual target implementation class should derive from an
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// instantiation of Sized_target.
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template<int size, bool big_endian>
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class Sized_target : public Target
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// Make a new symbol table entry for the target. This should be
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// overridden by a target which needs additional information in the
755
// symbol table. This will only be called if has_make_symbol()
757
virtual Sized_symbol<size>*
759
{ gold_unreachable(); }
761
// Resolve a symbol for the target. This should be overridden by a
762
// target which needs to take special action. TO is the
763
// pre-existing symbol. SYM is the new symbol, seen in OBJECT.
764
// VERSION is the version of SYM. This will only be called if
765
// has_resolve() returns true.
767
resolve(Symbol*, const elfcpp::Sym<size, big_endian>&, Object*,
769
{ gold_unreachable(); }
771
// Process the relocs for a section, and record information of the
772
// mapping from source to destination sections. This mapping is later
773
// used to determine unreferenced garbage sections. This procedure is
774
// only called during garbage collection.
776
gc_process_relocs(Symbol_table* symtab,
778
Sized_relobj_file<size, big_endian>* object,
779
unsigned int data_shndx,
780
unsigned int sh_type,
781
const unsigned char* prelocs,
783
Output_section* output_section,
784
bool needs_special_offset_handling,
785
size_t local_symbol_count,
786
const unsigned char* plocal_symbols) = 0;
788
// Scan the relocs for a section, and record any information
789
// required for the symbol. SYMTAB is the symbol table. OBJECT is
790
// the object in which the section appears. DATA_SHNDX is the
791
// section index that these relocs apply to. SH_TYPE is the type of
792
// the relocation section, SHT_REL or SHT_RELA. PRELOCS points to
793
// the relocation data. RELOC_COUNT is the number of relocs.
794
// LOCAL_SYMBOL_COUNT is the number of local symbols.
795
// OUTPUT_SECTION is the output section.
796
// NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets to the output
797
// sections are not mapped as usual. PLOCAL_SYMBOLS points to the
798
// local symbol data from OBJECT. GLOBAL_SYMBOLS is the array of
799
// pointers to the global symbol table from OBJECT.
801
scan_relocs(Symbol_table* symtab,
803
Sized_relobj_file<size, big_endian>* object,
804
unsigned int data_shndx,
805
unsigned int sh_type,
806
const unsigned char* prelocs,
808
Output_section* output_section,
809
bool needs_special_offset_handling,
810
size_t local_symbol_count,
811
const unsigned char* plocal_symbols) = 0;
813
// Relocate section data. SH_TYPE is the type of the relocation
814
// section, SHT_REL or SHT_RELA. PRELOCS points to the relocation
815
// information. RELOC_COUNT is the number of relocs.
816
// OUTPUT_SECTION is the output section.
817
// NEEDS_SPECIAL_OFFSET_HANDLING is true if offsets must be mapped
818
// to correspond to the output section. VIEW is a view into the
819
// output file holding the section contents, VIEW_ADDRESS is the
820
// virtual address of the view, and VIEW_SIZE is the size of the
821
// view. If NEEDS_SPECIAL_OFFSET_HANDLING is true, the VIEW_xx
822
// parameters refer to the complete output section data, not just
823
// the input section data.
825
relocate_section(const Relocate_info<size, big_endian>*,
826
unsigned int sh_type,
827
const unsigned char* prelocs,
829
Output_section* output_section,
830
bool needs_special_offset_handling,
832
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
833
section_size_type view_size,
834
const Reloc_symbol_changes*) = 0;
836
// Scan the relocs during a relocatable link. The parameters are
837
// like scan_relocs, with an additional Relocatable_relocs
838
// parameter, used to record the disposition of the relocs.
840
scan_relocatable_relocs(Symbol_table* symtab,
842
Sized_relobj_file<size, big_endian>* object,
843
unsigned int data_shndx,
844
unsigned int sh_type,
845
const unsigned char* prelocs,
847
Output_section* output_section,
848
bool needs_special_offset_handling,
849
size_t local_symbol_count,
850
const unsigned char* plocal_symbols,
851
Relocatable_relocs*) = 0;
853
// Emit relocations for a section during a relocatable link, and for
854
// --emit-relocs. The parameters are like relocate_section, with
855
// additional parameters for the view of the output reloc section.
857
relocate_relocs(const Relocate_info<size, big_endian>*,
858
unsigned int sh_type,
859
const unsigned char* prelocs,
861
Output_section* output_section,
862
typename elfcpp::Elf_types<size>::Elf_Off
863
offset_in_output_section,
864
const Relocatable_relocs*,
866
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
867
section_size_type view_size,
868
unsigned char* reloc_view,
869
section_size_type reloc_view_size) = 0;
871
// Perform target-specific processing in a relocatable link. This is
872
// only used if we use the relocation strategy RELOC_SPECIAL.
873
// RELINFO points to a Relocation_info structure. SH_TYPE is the relocation
874
// section type. PRELOC_IN points to the original relocation. RELNUM is
875
// the index number of the relocation in the relocation section.
876
// OUTPUT_SECTION is the output section to which the relocation is applied.
877
// OFFSET_IN_OUTPUT_SECTION is the offset of the relocation input section
878
// within the output section. VIEW points to the output view of the
879
// output section. VIEW_ADDRESS is output address of the view. VIEW_SIZE
880
// is the size of the output view and PRELOC_OUT points to the new
881
// relocation in the output object.
883
// A target only needs to override this if the generic code in
884
// target-reloc.h cannot handle some relocation types.
887
relocate_special_relocatable(const Relocate_info<size, big_endian>*
889
unsigned int /* sh_type */,
890
const unsigned char* /* preloc_in */,
892
Output_section* /* output_section */,
893
typename elfcpp::Elf_types<size>::Elf_Off
894
/* offset_in_output_section */,
895
unsigned char* /* view */,
896
typename elfcpp::Elf_types<size>::Elf_Addr
898
section_size_type /* view_size */,
899
unsigned char* /* preloc_out*/)
900
{ gold_unreachable(); }
902
// Return the number of entries in the GOT. This is only used for
903
// laying out the incremental link info sections. A target needs
904
// to implement this to support incremental linking.
907
got_entry_count() const
908
{ gold_unreachable(); }
910
// Return the number of entries in the PLT. This is only used for
911
// laying out the incremental link info sections. A target needs
912
// to implement this to support incremental linking.
915
plt_entry_count() const
916
{ gold_unreachable(); }
918
// Return the offset of the first non-reserved PLT entry. This is
919
// only used for laying out the incremental link info sections.
920
// A target needs to implement this to support incremental linking.
923
first_plt_entry_offset() const
924
{ gold_unreachable(); }
926
// Return the size of each PLT entry. This is only used for
927
// laying out the incremental link info sections. A target needs
928
// to implement this to support incremental linking.
931
plt_entry_size() const
932
{ gold_unreachable(); }
934
// Create the GOT and PLT sections for an incremental update.
935
// A target needs to implement this to support incremental linking.
937
virtual Output_data_got_base*
938
init_got_plt_for_update(Symbol_table*,
940
unsigned int /* got_count */,
941
unsigned int /* plt_count */)
942
{ gold_unreachable(); }
944
// Reserve a GOT entry for a local symbol, and regenerate any
945
// necessary dynamic relocations.
947
reserve_local_got_entry(unsigned int /* got_index */,
948
Sized_relobj<size, big_endian>* /* obj */,
949
unsigned int /* r_sym */,
950
unsigned int /* got_type */)
951
{ gold_unreachable(); }
953
// Reserve a GOT entry for a global symbol, and regenerate any
954
// necessary dynamic relocations.
956
reserve_global_got_entry(unsigned int /* got_index */, Symbol* /* gsym */,
957
unsigned int /* got_type */)
958
{ gold_unreachable(); }
960
// Register an existing PLT entry for a global symbol.
961
// A target needs to implement this to support incremental linking.
964
register_global_plt_entry(Symbol_table*, Layout*,
965
unsigned int /* plt_index */,
967
{ gold_unreachable(); }
969
// Force a COPY relocation for a given symbol.
970
// A target needs to implement this to support incremental linking.
973
emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t)
974
{ gold_unreachable(); }
976
// Apply an incremental relocation.
979
apply_relocation(const Relocate_info<size, big_endian>* /* relinfo */,
980
typename elfcpp::Elf_types<size>::Elf_Addr /* r_offset */,
981
unsigned int /* r_type */,
982
typename elfcpp::Elf_types<size>::Elf_Swxword /* r_addend */,
983
const Symbol* /* gsym */,
984
unsigned char* /* view */,
985
typename elfcpp::Elf_types<size>::Elf_Addr /* address */,
986
section_size_type /* view_size */)
987
{ gold_unreachable(); }
989
// Handle target specific gc actions when adding a gc reference from
990
// SRC_OBJ, SRC_SHNDX to a location specified by DST_OBJ, DST_SHNDX
993
gc_add_reference(Symbol_table* symtab,
995
unsigned int src_shndx,
997
unsigned int dst_shndx,
998
typename elfcpp::Elf_types<size>::Elf_Addr dst_off) const
1000
this->do_gc_add_reference(symtab, src_obj, src_shndx,
1001
dst_obj, dst_shndx, dst_off);
1005
Sized_target(const Target::Target_info* pti)
1008
gold_assert(pti->size == size);
1009
gold_assert(pti->is_big_endian ? big_endian : !big_endian);
1012
// Set the EI_OSABI field if requested.
1014
do_adjust_elf_header(unsigned char*, int) const;
1016
// Handle target specific gc actions when adding a gc reference.
1018
do_gc_add_reference(Symbol_table*, Object*, unsigned int,
1019
Object*, unsigned int,
1020
typename elfcpp::Elf_types<size>::Elf_Addr) const
1024
do_function_location(Symbol_location*) const
1028
} // End namespace gold.
1030
#endif // !defined(GOLD_TARGET_H)
added
removed
binutils-2.23.52.20130611/gold/target.h
