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jlechner |
// ehframe.cc -- handle exception frame sections for gold
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// Copyright 2006, 2007, 2008 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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#include "gold.h"
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#include <cstring>
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#include <algorithm>
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#include "elfcpp.h"
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#include "dwarf.h"
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#include "symtab.h"
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#include "reloc.h"
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#include "ehframe.h"
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namespace gold
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{
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// This file handles generation of the exception frame header that
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// gcc's runtime support libraries use to find unwind information at
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// runtime. This file also handles discarding duplicate exception
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// frame information.
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// The exception frame header starts with four bytes:
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// 0: The version number, currently 1.
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// 1: The encoding of the pointer to the exception frames. This can
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// be any DWARF unwind encoding (DW_EH_PE_*). It is normally a 4
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// byte PC relative offset (DW_EH_PE_pcrel | DW_EH_PE_sdata4).
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// 2: The encoding of the count of the number of FDE pointers in the
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// lookup table. This can be any DWARF unwind encoding, and in
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// particular can be DW_EH_PE_omit if the count is omitted. It is
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// normally a 4 byte unsigned count (DW_EH_PE_udata4).
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// 3: The encoding of the lookup table entries. Currently gcc's
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// libraries will only support DW_EH_PE_datarel | DW_EH_PE_sdata4,
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// which means that the values are 4 byte offsets from the start of
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// the table.
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// The exception frame header is followed by a pointer to the contents
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// of the exception frame section (.eh_frame). This pointer is
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// encoded as specified in the byte at offset 1 of the header (i.e.,
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// it is normally a 4 byte PC relative offset).
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// If there is a lookup table, this is followed by the count of the
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// number of FDE pointers, encoded as specified in the byte at offset
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// 2 of the header (i.e., normally a 4 byte unsigned integer).
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// This is followed by the table, which should start at an 4-byte
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// aligned address in memory. Each entry in the table is 8 bytes.
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// Each entry represents an FDE. The first four bytes of each entry
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// are an offset to the starting PC for the FDE. The last four bytes
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// of each entry are an offset to the FDE data. The offsets are from
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// the start of the exception frame header information. The entries
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// are in sorted order by starting PC.
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const int eh_frame_hdr_size = 4;
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// Construct the exception frame header.
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Eh_frame_hdr::Eh_frame_hdr(Output_section* eh_frame_section,
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const Eh_frame* eh_frame_data)
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: Output_section_data(4),
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eh_frame_section_(eh_frame_section),
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eh_frame_data_(eh_frame_data),
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fde_offsets_(),
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any_unrecognized_eh_frame_sections_(false)
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{
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}
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// Set the size of the exception frame header.
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void
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Eh_frame_hdr::set_final_data_size()
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{
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unsigned int data_size = eh_frame_hdr_size + 4;
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if (!this->any_unrecognized_eh_frame_sections_)
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{
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unsigned int fde_count = this->eh_frame_data_->fde_count();
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if (fde_count != 0)
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data_size += 4 + 8 * fde_count;
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this->fde_offsets_.reserve(fde_count);
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}
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this->set_data_size(data_size);
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}
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// Write the data to the flie.
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void
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Eh_frame_hdr::do_write(Output_file* of)
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{
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switch (parameters->size_and_endianness())
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{
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#ifdef HAVE_TARGET_32_LITTLE
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case Parameters::TARGET_32_LITTLE:
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this->do_sized_write<32, false>(of);
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break;
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#endif
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#ifdef HAVE_TARGET_32_BIG
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case Parameters::TARGET_32_BIG:
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this->do_sized_write<32, true>(of);
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break;
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#endif
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#ifdef HAVE_TARGET_64_LITTLE
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case Parameters::TARGET_64_LITTLE:
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this->do_sized_write<64, false>(of);
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break;
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#endif
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#ifdef HAVE_TARGET_64_BIG
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case Parameters::TARGET_64_BIG:
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this->do_sized_write<64, true>(of);
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break;
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#endif
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default:
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gold_unreachable();
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}
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}
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// Write the data to the file with the right endianness.
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template<int size, bool big_endian>
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void
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Eh_frame_hdr::do_sized_write(Output_file* of)
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{
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const off_t off = this->offset();
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const off_t oview_size = this->data_size();
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unsigned char* const oview = of->get_output_view(off, oview_size);
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// Version number.
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oview[0] = 1;
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// Write out a 4 byte PC relative offset to the address of the
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// .eh_frame section.
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oview[1] = elfcpp::DW_EH_PE_pcrel | elfcpp::DW_EH_PE_sdata4;
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uint64_t eh_frame_address = this->eh_frame_section_->address();
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uint64_t eh_frame_hdr_address = this->address();
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uint64_t eh_frame_offset = (eh_frame_address -
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(eh_frame_hdr_address + 4));
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elfcpp::Swap<32, big_endian>::writeval(oview + 4, eh_frame_offset);
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if (this->any_unrecognized_eh_frame_sections_
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|| this->fde_offsets_.empty())
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{
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// There are no FDEs, or we didn't recognize the format of the
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// some of the .eh_frame sections, so we can't write out the
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// sorted table.
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oview[2] = elfcpp::DW_EH_PE_omit;
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oview[3] = elfcpp::DW_EH_PE_omit;
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gold_assert(oview_size == 8);
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}
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else
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{
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oview[2] = elfcpp::DW_EH_PE_udata4;
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oview[3] = elfcpp::DW_EH_PE_datarel | elfcpp::DW_EH_PE_sdata4;
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elfcpp::Swap<32, big_endian>::writeval(oview + 8,
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this->fde_offsets_.size());
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// We have the offsets of the FDEs in the .eh_frame section. We
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// couldn't easily get the PC values before, as they depend on
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// relocations which are, of course, target specific. This code
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// is run after all those relocations have been applied to the
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// output file. Here we read the output file again to find the
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// PC values. Then we sort the list and write it out.
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Fde_addresses<size> fde_addresses(this->fde_offsets_.size());
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this->get_fde_addresses<size, big_endian>(of, &this->fde_offsets_,
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&fde_addresses);
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std::sort(fde_addresses.begin(), fde_addresses.end(),
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Fde_address_compare<size>());
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typename elfcpp::Elf_types<size>::Elf_Addr output_address;
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output_address = this->address();
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unsigned char* pfde = oview + 12;
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for (typename Fde_addresses<size>::iterator p = fde_addresses.begin();
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p != fde_addresses.end();
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++p)
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{
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elfcpp::Swap<32, big_endian>::writeval(pfde,
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p->first - output_address);
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elfcpp::Swap<32, big_endian>::writeval(pfde + 4,
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p->second - output_address);
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pfde += 8;
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}
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gold_assert(pfde - oview == oview_size);
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}
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of->write_output_view(off, oview_size, oview);
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}
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// Given the offset FDE_OFFSET of an FDE in the .eh_frame section, and
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// the contents of the .eh_frame section EH_FRAME_CONTENTS, where the
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// FDE's encoding is FDE_ENCODING, return the output address of the
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// FDE's PC.
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template<int size, bool big_endian>
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typename elfcpp::Elf_types<size>::Elf_Addr
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Eh_frame_hdr::get_fde_pc(
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typename elfcpp::Elf_types<size>::Elf_Addr eh_frame_address,
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const unsigned char* eh_frame_contents,
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section_offset_type fde_offset,
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unsigned char fde_encoding)
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{
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// The FDE starts with a 4 byte length and a 4 byte offset to the
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// CIE. The PC follows.
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const unsigned char* p = eh_frame_contents + fde_offset + 8;
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typename elfcpp::Elf_types<size>::Elf_Addr pc;
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bool is_signed = (fde_encoding & elfcpp::DW_EH_PE_signed) != 0;
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int pc_size = fde_encoding & 7;
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if (pc_size == elfcpp::DW_EH_PE_absptr)
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{
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if (size == 32)
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pc_size = elfcpp::DW_EH_PE_udata4;
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else if (size == 64)
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pc_size = elfcpp::DW_EH_PE_udata8;
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else
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gold_unreachable();
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}
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switch (pc_size)
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{
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case elfcpp::DW_EH_PE_udata2:
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pc = elfcpp::Swap<16, big_endian>::readval(p);
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if (is_signed)
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pc = (pc ^ 0x8000) - 0x8000;
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break;
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case elfcpp::DW_EH_PE_udata4:
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pc = elfcpp::Swap<32, big_endian>::readval(p);
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if (size > 32 && is_signed)
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pc = (pc ^ 0x80000000) - 0x80000000;
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break;
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case elfcpp::DW_EH_PE_udata8:
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gold_assert(size == 64);
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pc = elfcpp::Swap_unaligned<64, big_endian>::readval(p);
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break;
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default:
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// All other cases were rejected in Eh_frame::read_cie.
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gold_unreachable();
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}
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switch (fde_encoding & 0xf0)
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{
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case 0:
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break;
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case elfcpp::DW_EH_PE_pcrel:
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pc += eh_frame_address + fde_offset + 8;
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break;
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default:
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// If other cases arise, then we have to handle them, or we have
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// to reject them by returning false in Eh_frame::read_cie.
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gold_unreachable();
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}
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return pc;
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}
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// Given an array of FDE offsets in the .eh_frame section, return an
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// array of offsets from the exception frame header to the FDE's
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// output PC and to the output address of the FDE itself. We get the
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// FDE's PC by actually looking in the .eh_frame section we just wrote
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// to the output file.
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template<int size, bool big_endian>
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void
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Eh_frame_hdr::get_fde_addresses(Output_file* of,
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const Fde_offsets* fde_offsets,
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Fde_addresses<size>* fde_addresses)
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{
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typename elfcpp::Elf_types<size>::Elf_Addr eh_frame_address;
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eh_frame_address = this->eh_frame_section_->address();
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off_t eh_frame_offset = this->eh_frame_section_->offset();
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off_t eh_frame_size = this->eh_frame_section_->data_size();
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const unsigned char* eh_frame_contents = of->get_input_view(eh_frame_offset,
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eh_frame_size);
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for (Fde_offsets::const_iterator p = fde_offsets->begin();
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p != fde_offsets->end();
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++p)
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{
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typename elfcpp::Elf_types<size>::Elf_Addr fde_pc;
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fde_pc = this->get_fde_pc<size, big_endian>(eh_frame_address,
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eh_frame_contents,
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p->first, p->second);
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fde_addresses->push_back(fde_pc, eh_frame_address + p->first);
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}
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of->free_input_view(eh_frame_offset, eh_frame_size, eh_frame_contents);
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}
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// Class Fde.
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// Write the FDE to OVIEW starting at OFFSET. CIE_OFFSET is the
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// offset of the CIE in OVIEW. FDE_ENCODING is the encoding, from the
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// CIE. ADDRALIGN is the required alignment. Record the FDE pc for
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// EH_FRAME_HDR. Return the new offset.
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326 |
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template<int size, bool big_endian>
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section_offset_type
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Fde::write(unsigned char* oview, section_offset_type offset,
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unsigned int addralign, section_offset_type cie_offset,
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unsigned char fde_encoding, Eh_frame_hdr* eh_frame_hdr)
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{
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gold_assert((offset & (addralign - 1)) == 0);
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size_t length = this->contents_.length();
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336 |
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337 |
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// We add 8 when getting the aligned length to account for the
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338 |
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// length word and the CIE offset.
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339 |
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size_t aligned_full_length = align_address(length + 8, addralign);
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340 |
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341 |
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// Write the length of the FDE as a 32-bit word. The length word
|
342 |
|
|
// does not include the four bytes of the length word itself, but it
|
343 |
|
|
// does include the offset to the CIE.
|
344 |
|
|
elfcpp::Swap<32, big_endian>::writeval(oview + offset,
|
345 |
|
|
aligned_full_length - 4);
|
346 |
|
|
|
347 |
|
|
// Write the offset to the CIE as a 32-bit word. This is the
|
348 |
|
|
// difference between the address of the offset word itself and the
|
349 |
|
|
// CIE address.
|
350 |
|
|
elfcpp::Swap<32, big_endian>::writeval(oview + offset + 4,
|
351 |
|
|
offset + 4 - cie_offset);
|
352 |
|
|
|
353 |
|
|
// Copy the rest of the FDE. Note that this is run before
|
354 |
|
|
// relocation processing is done on this section, so the relocations
|
355 |
|
|
// will later be applied to the FDE data.
|
356 |
|
|
memcpy(oview + offset + 8, this->contents_.data(), length);
|
357 |
|
|
|
358 |
|
|
if (aligned_full_length > length + 8)
|
359 |
|
|
memset(oview + offset + length + 8, 0, aligned_full_length - (length + 8));
|
360 |
|
|
|
361 |
|
|
// Tell the exception frame header about this FDE.
|
362 |
|
|
if (eh_frame_hdr != NULL)
|
363 |
|
|
eh_frame_hdr->record_fde(offset, fde_encoding);
|
364 |
|
|
|
365 |
|
|
return offset + aligned_full_length;
|
366 |
|
|
}
|
367 |
|
|
|
368 |
|
|
// Class Cie.
|
369 |
|
|
|
370 |
|
|
// Destructor.
|
371 |
|
|
|
372 |
|
|
Cie::~Cie()
|
373 |
|
|
{
|
374 |
|
|
for (std::vector<Fde*>::iterator p = this->fdes_.begin();
|
375 |
|
|
p != this->fdes_.end();
|
376 |
|
|
++p)
|
377 |
|
|
delete *p;
|
378 |
|
|
}
|
379 |
|
|
|
380 |
|
|
// Set the output offset of a CIE. Return the new output offset.
|
381 |
|
|
|
382 |
|
|
section_offset_type
|
383 |
|
|
Cie::set_output_offset(section_offset_type output_offset,
|
384 |
|
|
unsigned int addralign,
|
385 |
|
|
Merge_map* merge_map)
|
386 |
|
|
{
|
387 |
|
|
size_t length = this->contents_.length();
|
388 |
|
|
|
389 |
|
|
// Add 4 for length and 4 for zero CIE identifier tag.
|
390 |
|
|
length += 8;
|
391 |
|
|
|
392 |
|
|
merge_map->add_mapping(this->object_, this->shndx_, this->input_offset_,
|
393 |
|
|
length, output_offset);
|
394 |
|
|
|
395 |
|
|
length = align_address(length, addralign);
|
396 |
|
|
|
397 |
|
|
for (std::vector<Fde*>::const_iterator p = this->fdes_.begin();
|
398 |
|
|
p != this->fdes_.end();
|
399 |
|
|
++p)
|
400 |
|
|
{
|
401 |
|
|
(*p)->add_mapping(output_offset + length, merge_map);
|
402 |
|
|
|
403 |
|
|
size_t fde_length = (*p)->length();
|
404 |
|
|
fde_length = align_address(fde_length, addralign);
|
405 |
|
|
length += fde_length;
|
406 |
|
|
}
|
407 |
|
|
|
408 |
|
|
return output_offset + length;
|
409 |
|
|
}
|
410 |
|
|
|
411 |
|
|
// Write the CIE to OVIEW starting at OFFSET. EH_FRAME_HDR is for FDE
|
412 |
|
|
// recording. Round up the bytes to ADDRALIGN. Return the new
|
413 |
|
|
// offset.
|
414 |
|
|
|
415 |
|
|
template<int size, bool big_endian>
|
416 |
|
|
section_offset_type
|
417 |
|
|
Cie::write(unsigned char* oview, section_offset_type offset,
|
418 |
|
|
unsigned int addralign, Eh_frame_hdr* eh_frame_hdr)
|
419 |
|
|
{
|
420 |
|
|
gold_assert((offset & (addralign - 1)) == 0);
|
421 |
|
|
|
422 |
|
|
section_offset_type cie_offset = offset;
|
423 |
|
|
|
424 |
|
|
size_t length = this->contents_.length();
|
425 |
|
|
|
426 |
|
|
// We add 8 when getting the aligned length to account for the
|
427 |
|
|
// length word and the CIE tag.
|
428 |
|
|
size_t aligned_full_length = align_address(length + 8, addralign);
|
429 |
|
|
|
430 |
|
|
// Write the length of the CIE as a 32-bit word. The length word
|
431 |
|
|
// does not include the four bytes of the length word itself.
|
432 |
|
|
elfcpp::Swap<32, big_endian>::writeval(oview + offset,
|
433 |
|
|
aligned_full_length - 4);
|
434 |
|
|
|
435 |
|
|
// Write the tag which marks this as a CIE: a 32-bit zero.
|
436 |
|
|
elfcpp::Swap<32, big_endian>::writeval(oview + offset + 4, 0);
|
437 |
|
|
|
438 |
|
|
// Write out the CIE data.
|
439 |
|
|
memcpy(oview + offset + 8, this->contents_.data(), length);
|
440 |
|
|
|
441 |
|
|
if (aligned_full_length > length + 8)
|
442 |
|
|
memset(oview + offset + length + 8, 0, aligned_full_length - (length + 8));
|
443 |
|
|
|
444 |
|
|
offset += aligned_full_length;
|
445 |
|
|
|
446 |
|
|
// Write out the associated FDEs.
|
447 |
|
|
unsigned char fde_encoding = this->fde_encoding_;
|
448 |
|
|
for (std::vector<Fde*>::const_iterator p = this->fdes_.begin();
|
449 |
|
|
p != this->fdes_.end();
|
450 |
|
|
++p)
|
451 |
|
|
offset = (*p)->write<size, big_endian>(oview, offset, addralign,
|
452 |
|
|
cie_offset, fde_encoding,
|
453 |
|
|
eh_frame_hdr);
|
454 |
|
|
|
455 |
|
|
return offset;
|
456 |
|
|
}
|
457 |
|
|
|
458 |
|
|
// We track all the CIEs we see, and merge them when possible. This
|
459 |
|
|
// works because each FDE holds an offset to the relevant CIE: we
|
460 |
|
|
// rewrite the FDEs to point to the merged CIE. This is worthwhile
|
461 |
|
|
// because in a typical C++ program many FDEs in many different object
|
462 |
|
|
// files will use the same CIE.
|
463 |
|
|
|
464 |
|
|
// An equality operator for Cie.
|
465 |
|
|
|
466 |
|
|
bool
|
467 |
|
|
operator==(const Cie& cie1, const Cie& cie2)
|
468 |
|
|
{
|
469 |
|
|
return (cie1.personality_name_ == cie2.personality_name_
|
470 |
|
|
&& cie1.contents_ == cie2.contents_);
|
471 |
|
|
}
|
472 |
|
|
|
473 |
|
|
// A less-than operator for Cie.
|
474 |
|
|
|
475 |
|
|
bool
|
476 |
|
|
operator<(const Cie& cie1, const Cie& cie2)
|
477 |
|
|
{
|
478 |
|
|
if (cie1.personality_name_ != cie2.personality_name_)
|
479 |
|
|
return cie1.personality_name_ < cie2.personality_name_;
|
480 |
|
|
return cie1.contents_ < cie2.contents_;
|
481 |
|
|
}
|
482 |
|
|
|
483 |
|
|
// Class Eh_frame.
|
484 |
|
|
|
485 |
|
|
Eh_frame::Eh_frame()
|
486 |
|
|
: Output_section_data(Output_data::default_alignment()),
|
487 |
|
|
eh_frame_hdr_(NULL),
|
488 |
|
|
cie_offsets_(),
|
489 |
|
|
unmergeable_cie_offsets_(),
|
490 |
|
|
merge_map_(),
|
491 |
|
|
mappings_are_done_(false),
|
492 |
|
|
final_data_size_(0)
|
493 |
|
|
{
|
494 |
|
|
}
|
495 |
|
|
|
496 |
|
|
// Skip an LEB128, updating *PP to point to the next character.
|
497 |
|
|
// Return false if we ran off the end of the string.
|
498 |
|
|
|
499 |
|
|
bool
|
500 |
|
|
Eh_frame::skip_leb128(const unsigned char** pp, const unsigned char* pend)
|
501 |
|
|
{
|
502 |
|
|
const unsigned char* p;
|
503 |
|
|
for (p = *pp; p < pend; ++p)
|
504 |
|
|
{
|
505 |
|
|
if ((*p & 0x80) == 0)
|
506 |
|
|
{
|
507 |
|
|
*pp = p + 1;
|
508 |
|
|
return true;
|
509 |
|
|
}
|
510 |
|
|
}
|
511 |
|
|
return false;
|
512 |
|
|
}
|
513 |
|
|
|
514 |
|
|
// Add input section SHNDX in OBJECT to an exception frame section.
|
515 |
|
|
// SYMBOLS is the contents of the symbol table section (size
|
516 |
|
|
// SYMBOLS_SIZE), SYMBOL_NAMES is the symbol names section (size
|
517 |
|
|
// SYMBOL_NAMES_SIZE). RELOC_SHNDX is the index of a relocation
|
518 |
|
|
// section applying to SHNDX, or 0 if none, or -1U if more than one.
|
519 |
|
|
// RELOC_TYPE is the type of the reloc section if there is one, either
|
520 |
|
|
// SHT_REL or SHT_RELA. We try to parse the input exception frame
|
521 |
|
|
// data into our data structures. If we can't do it, we return false
|
522 |
|
|
// to mean that the section should be handled as a normal input
|
523 |
|
|
// section.
|
524 |
|
|
|
525 |
|
|
template<int size, bool big_endian>
|
526 |
|
|
bool
|
527 |
|
|
Eh_frame::add_ehframe_input_section(
|
528 |
|
|
Sized_relobj<size, big_endian>* object,
|
529 |
|
|
const unsigned char* symbols,
|
530 |
|
|
section_size_type symbols_size,
|
531 |
|
|
const unsigned char* symbol_names,
|
532 |
|
|
section_size_type symbol_names_size,
|
533 |
|
|
unsigned int shndx,
|
534 |
|
|
unsigned int reloc_shndx,
|
535 |
|
|
unsigned int reloc_type)
|
536 |
|
|
{
|
537 |
|
|
// Get the section contents.
|
538 |
|
|
section_size_type contents_len;
|
539 |
|
|
const unsigned char* pcontents = object->section_contents(shndx,
|
540 |
|
|
&contents_len,
|
541 |
|
|
false);
|
542 |
|
|
if (contents_len == 0)
|
543 |
|
|
return false;
|
544 |
|
|
|
545 |
|
|
// If this is the marker section for the end of the data, then
|
546 |
|
|
// return false to force it to be handled as an ordinary input
|
547 |
|
|
// section. If we don't do this, we won't correctly handle the case
|
548 |
|
|
// of unrecognized .eh_frame sections.
|
549 |
|
|
if (contents_len == 4
|
550 |
|
|
&& elfcpp::Swap<32, big_endian>::readval(pcontents) == 0)
|
551 |
|
|
return false;
|
552 |
|
|
|
553 |
|
|
New_cies new_cies;
|
554 |
|
|
if (!this->do_add_ehframe_input_section(object, symbols, symbols_size,
|
555 |
|
|
symbol_names, symbol_names_size,
|
556 |
|
|
shndx, reloc_shndx,
|
557 |
|
|
reloc_type, pcontents,
|
558 |
|
|
contents_len, &new_cies))
|
559 |
|
|
{
|
560 |
|
|
if (this->eh_frame_hdr_ != NULL)
|
561 |
|
|
this->eh_frame_hdr_->found_unrecognized_eh_frame_section();
|
562 |
|
|
|
563 |
|
|
for (New_cies::iterator p = new_cies.begin();
|
564 |
|
|
p != new_cies.end();
|
565 |
|
|
++p)
|
566 |
|
|
delete p->first;
|
567 |
|
|
|
568 |
|
|
return false;
|
569 |
|
|
}
|
570 |
|
|
|
571 |
|
|
// Now that we know we are using this section, record any new CIEs
|
572 |
|
|
// that we found.
|
573 |
|
|
for (New_cies::const_iterator p = new_cies.begin();
|
574 |
|
|
p != new_cies.end();
|
575 |
|
|
++p)
|
576 |
|
|
{
|
577 |
|
|
if (p->second)
|
578 |
|
|
this->cie_offsets_.insert(p->first);
|
579 |
|
|
else
|
580 |
|
|
this->unmergeable_cie_offsets_.push_back(p->first);
|
581 |
|
|
}
|
582 |
|
|
|
583 |
|
|
return true;
|
584 |
|
|
}
|
585 |
|
|
|
586 |
|
|
// The bulk of the implementation of add_ehframe_input_section.
|
587 |
|
|
|
588 |
|
|
template<int size, bool big_endian>
|
589 |
|
|
bool
|
590 |
|
|
Eh_frame::do_add_ehframe_input_section(
|
591 |
|
|
Sized_relobj<size, big_endian>* object,
|
592 |
|
|
const unsigned char* symbols,
|
593 |
|
|
section_size_type symbols_size,
|
594 |
|
|
const unsigned char* symbol_names,
|
595 |
|
|
section_size_type symbol_names_size,
|
596 |
|
|
unsigned int shndx,
|
597 |
|
|
unsigned int reloc_shndx,
|
598 |
|
|
unsigned int reloc_type,
|
599 |
|
|
const unsigned char* pcontents,
|
600 |
|
|
section_size_type contents_len,
|
601 |
|
|
New_cies* new_cies)
|
602 |
|
|
{
|
603 |
|
|
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
|
604 |
|
|
Track_relocs<size, big_endian> relocs;
|
605 |
|
|
|
606 |
|
|
const unsigned char* p = pcontents;
|
607 |
|
|
const unsigned char* pend = p + contents_len;
|
608 |
|
|
|
609 |
|
|
// Get the contents of the reloc section if any.
|
610 |
|
|
if (!relocs.initialize(object, reloc_shndx, reloc_type))
|
611 |
|
|
return false;
|
612 |
|
|
|
613 |
|
|
// Keep track of which CIEs are at which offsets.
|
614 |
|
|
Offsets_to_cie cies;
|
615 |
|
|
|
616 |
|
|
while (p < pend)
|
617 |
|
|
{
|
618 |
|
|
if (pend - p < 4)
|
619 |
|
|
return false;
|
620 |
|
|
|
621 |
|
|
// There shouldn't be any relocations here.
|
622 |
|
|
if (relocs.advance(p + 4 - pcontents) > 0)
|
623 |
|
|
return false;
|
624 |
|
|
|
625 |
|
|
unsigned int len = elfcpp::Swap<32, big_endian>::readval(p);
|
626 |
|
|
p += 4;
|
627 |
|
|
if (len == 0)
|
628 |
|
|
{
|
629 |
|
|
// We should only find a zero-length entry at the end of the
|
630 |
|
|
// section.
|
631 |
|
|
if (p < pend)
|
632 |
|
|
return false;
|
633 |
|
|
break;
|
634 |
|
|
}
|
635 |
|
|
// We don't support a 64-bit .eh_frame.
|
636 |
|
|
if (len == 0xffffffff)
|
637 |
|
|
return false;
|
638 |
|
|
if (static_cast<unsigned int>(pend - p) < len)
|
639 |
|
|
return false;
|
640 |
|
|
|
641 |
|
|
const unsigned char* const pentend = p + len;
|
642 |
|
|
|
643 |
|
|
if (pend - p < 4)
|
644 |
|
|
return false;
|
645 |
|
|
if (relocs.advance(p + 4 - pcontents) > 0)
|
646 |
|
|
return false;
|
647 |
|
|
|
648 |
|
|
unsigned int id = elfcpp::Swap<32, big_endian>::readval(p);
|
649 |
|
|
p += 4;
|
650 |
|
|
|
651 |
|
|
if (id == 0)
|
652 |
|
|
{
|
653 |
|
|
// CIE.
|
654 |
|
|
if (!this->read_cie(object, shndx, symbols, symbols_size,
|
655 |
|
|
symbol_names, symbol_names_size,
|
656 |
|
|
pcontents, p, pentend, &relocs, &cies,
|
657 |
|
|
new_cies))
|
658 |
|
|
return false;
|
659 |
|
|
}
|
660 |
|
|
else
|
661 |
|
|
{
|
662 |
|
|
// FDE.
|
663 |
|
|
if (!this->read_fde(object, shndx, symbols, symbols_size,
|
664 |
|
|
pcontents, id, p, pentend, &relocs, &cies))
|
665 |
|
|
return false;
|
666 |
|
|
}
|
667 |
|
|
|
668 |
|
|
p = pentend;
|
669 |
|
|
}
|
670 |
|
|
|
671 |
|
|
return true;
|
672 |
|
|
}
|
673 |
|
|
|
674 |
|
|
// Read a CIE. Return false if we can't parse the information.
|
675 |
|
|
|
676 |
|
|
template<int size, bool big_endian>
|
677 |
|
|
bool
|
678 |
|
|
Eh_frame::read_cie(Sized_relobj<size, big_endian>* object,
|
679 |
|
|
unsigned int shndx,
|
680 |
|
|
const unsigned char* symbols,
|
681 |
|
|
section_size_type symbols_size,
|
682 |
|
|
const unsigned char* symbol_names,
|
683 |
|
|
section_size_type symbol_names_size,
|
684 |
|
|
const unsigned char* pcontents,
|
685 |
|
|
const unsigned char* pcie,
|
686 |
|
|
const unsigned char *pcieend,
|
687 |
|
|
Track_relocs<size, big_endian>* relocs,
|
688 |
|
|
Offsets_to_cie* cies,
|
689 |
|
|
New_cies* new_cies)
|
690 |
|
|
{
|
691 |
|
|
bool mergeable = true;
|
692 |
|
|
|
693 |
|
|
// We need to find the personality routine if there is one, since we
|
694 |
|
|
// can only merge CIEs which use the same routine. We also need to
|
695 |
|
|
// find the FDE encoding if there is one, so that we can read the PC
|
696 |
|
|
// from the FDE.
|
697 |
|
|
|
698 |
|
|
const unsigned char* p = pcie;
|
699 |
|
|
|
700 |
|
|
if (pcieend - p < 1)
|
701 |
|
|
return false;
|
702 |
|
|
unsigned char version = *p++;
|
703 |
|
|
if (version != 1 && version != 3)
|
704 |
|
|
return false;
|
705 |
|
|
|
706 |
|
|
const unsigned char* paug = p;
|
707 |
|
|
const void* paugendv = memchr(p, '\0', pcieend - p);
|
708 |
|
|
const unsigned char* paugend = static_cast<const unsigned char*>(paugendv);
|
709 |
|
|
if (paugend == NULL)
|
710 |
|
|
return false;
|
711 |
|
|
p = paugend + 1;
|
712 |
|
|
|
713 |
|
|
if (paug[0] == 'e' && paug[1] == 'h')
|
714 |
|
|
{
|
715 |
|
|
// This is a CIE from gcc before version 3.0. We can't merge
|
716 |
|
|
// these. We can still read the FDEs.
|
717 |
|
|
mergeable = false;
|
718 |
|
|
paug += 2;
|
719 |
|
|
if (*paug != '\0')
|
720 |
|
|
return false;
|
721 |
|
|
if (pcieend - p < size / 8)
|
722 |
|
|
return false;
|
723 |
|
|
p += size / 8;
|
724 |
|
|
}
|
725 |
|
|
|
726 |
|
|
// Skip the code alignment.
|
727 |
|
|
if (!skip_leb128(&p, pcieend))
|
728 |
|
|
return false;
|
729 |
|
|
|
730 |
|
|
// Skip the data alignment.
|
731 |
|
|
if (!skip_leb128(&p, pcieend))
|
732 |
|
|
return false;
|
733 |
|
|
|
734 |
|
|
// Skip the return column.
|
735 |
|
|
if (version == 1)
|
736 |
|
|
{
|
737 |
|
|
if (pcieend - p < 1)
|
738 |
|
|
return false;
|
739 |
|
|
++p;
|
740 |
|
|
}
|
741 |
|
|
else
|
742 |
|
|
{
|
743 |
|
|
if (!skip_leb128(&p, pcieend))
|
744 |
|
|
return false;
|
745 |
|
|
}
|
746 |
|
|
|
747 |
|
|
if (*paug == 'z')
|
748 |
|
|
{
|
749 |
|
|
++paug;
|
750 |
|
|
// Skip the augmentation size.
|
751 |
|
|
if (!skip_leb128(&p, pcieend))
|
752 |
|
|
return false;
|
753 |
|
|
}
|
754 |
|
|
|
755 |
|
|
unsigned char fde_encoding = elfcpp::DW_EH_PE_absptr;
|
756 |
|
|
int per_offset = -1;
|
757 |
|
|
while (*paug != '\0')
|
758 |
|
|
{
|
759 |
|
|
switch (*paug)
|
760 |
|
|
{
|
761 |
|
|
case 'L': // LSDA encoding.
|
762 |
|
|
if (pcieend - p < 1)
|
763 |
|
|
return false;
|
764 |
|
|
++p;
|
765 |
|
|
break;
|
766 |
|
|
|
767 |
|
|
case 'R': // FDE encoding.
|
768 |
|
|
if (pcieend - p < 1)
|
769 |
|
|
return false;
|
770 |
|
|
fde_encoding = *p;
|
771 |
|
|
switch (fde_encoding & 7)
|
772 |
|
|
{
|
773 |
|
|
case elfcpp::DW_EH_PE_absptr:
|
774 |
|
|
case elfcpp::DW_EH_PE_udata2:
|
775 |
|
|
case elfcpp::DW_EH_PE_udata4:
|
776 |
|
|
case elfcpp::DW_EH_PE_udata8:
|
777 |
|
|
break;
|
778 |
|
|
default:
|
779 |
|
|
// We don't expect to see any other cases here, and
|
780 |
|
|
// we're not prepared to handle them.
|
781 |
|
|
return false;
|
782 |
|
|
}
|
783 |
|
|
++p;
|
784 |
|
|
break;
|
785 |
|
|
|
786 |
|
|
case 'S':
|
787 |
|
|
break;
|
788 |
|
|
|
789 |
|
|
case 'P':
|
790 |
|
|
// Personality encoding.
|
791 |
|
|
{
|
792 |
|
|
if (pcieend - p < 1)
|
793 |
|
|
return false;
|
794 |
|
|
unsigned char per_encoding = *p;
|
795 |
|
|
++p;
|
796 |
|
|
|
797 |
|
|
if ((per_encoding & 0x60) == 0x60)
|
798 |
|
|
return false;
|
799 |
|
|
unsigned int per_width;
|
800 |
|
|
switch (per_encoding & 7)
|
801 |
|
|
{
|
802 |
|
|
case elfcpp::DW_EH_PE_udata2:
|
803 |
|
|
per_width = 2;
|
804 |
|
|
break;
|
805 |
|
|
case elfcpp::DW_EH_PE_udata4:
|
806 |
|
|
per_width = 4;
|
807 |
|
|
break;
|
808 |
|
|
case elfcpp::DW_EH_PE_udata8:
|
809 |
|
|
per_width = 8;
|
810 |
|
|
break;
|
811 |
|
|
case elfcpp::DW_EH_PE_absptr:
|
812 |
|
|
per_width = size / 8;
|
813 |
|
|
break;
|
814 |
|
|
default:
|
815 |
|
|
return false;
|
816 |
|
|
}
|
817 |
|
|
|
818 |
|
|
if ((per_encoding & 0xf0) == elfcpp::DW_EH_PE_aligned)
|
819 |
|
|
{
|
820 |
|
|
unsigned int len = p - pcie;
|
821 |
|
|
len += per_width - 1;
|
822 |
|
|
len &= ~ (per_width - 1);
|
823 |
|
|
if (static_cast<unsigned int>(pcieend - p) < len)
|
824 |
|
|
return false;
|
825 |
|
|
p += len;
|
826 |
|
|
}
|
827 |
|
|
|
828 |
|
|
per_offset = p - pcontents;
|
829 |
|
|
|
830 |
|
|
if (static_cast<unsigned int>(pcieend - p) < per_width)
|
831 |
|
|
return false;
|
832 |
|
|
p += per_width;
|
833 |
|
|
}
|
834 |
|
|
break;
|
835 |
|
|
|
836 |
|
|
default:
|
837 |
|
|
return false;
|
838 |
|
|
}
|
839 |
|
|
|
840 |
|
|
++paug;
|
841 |
|
|
}
|
842 |
|
|
|
843 |
|
|
const char* personality_name = "";
|
844 |
|
|
if (per_offset != -1)
|
845 |
|
|
{
|
846 |
|
|
if (relocs->advance(per_offset) > 0)
|
847 |
|
|
return false;
|
848 |
|
|
if (relocs->next_offset() != per_offset)
|
849 |
|
|
return false;
|
850 |
|
|
|
851 |
|
|
unsigned int personality_symndx = relocs->next_symndx();
|
852 |
|
|
if (personality_symndx == -1U)
|
853 |
|
|
return false;
|
854 |
|
|
|
855 |
|
|
if (personality_symndx < object->local_symbol_count())
|
856 |
|
|
{
|
857 |
|
|
// We can only merge this CIE if the personality routine is
|
858 |
|
|
// a global symbol. We can still read the FDEs.
|
859 |
|
|
mergeable = false;
|
860 |
|
|
}
|
861 |
|
|
else
|
862 |
|
|
{
|
863 |
|
|
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
|
864 |
|
|
if (personality_symndx >= symbols_size / sym_size)
|
865 |
|
|
return false;
|
866 |
|
|
elfcpp::Sym<size, big_endian> sym(symbols
|
867 |
|
|
+ (personality_symndx * sym_size));
|
868 |
|
|
unsigned int name_offset = sym.get_st_name();
|
869 |
|
|
if (name_offset >= symbol_names_size)
|
870 |
|
|
return false;
|
871 |
|
|
personality_name = (reinterpret_cast<const char*>(symbol_names)
|
872 |
|
|
+ name_offset);
|
873 |
|
|
}
|
874 |
|
|
|
875 |
|
|
int r = relocs->advance(per_offset + 1);
|
876 |
|
|
gold_assert(r == 1);
|
877 |
|
|
}
|
878 |
|
|
|
879 |
|
|
if (relocs->advance(pcieend - pcontents) > 0)
|
880 |
|
|
return false;
|
881 |
|
|
|
882 |
|
|
Cie cie(object, shndx, (pcie - 8) - pcontents, fde_encoding,
|
883 |
|
|
personality_name, pcie, pcieend - pcie);
|
884 |
|
|
Cie* cie_pointer = NULL;
|
885 |
|
|
if (mergeable)
|
886 |
|
|
{
|
887 |
|
|
Cie_offsets::iterator find_cie = this->cie_offsets_.find(&cie);
|
888 |
|
|
if (find_cie != this->cie_offsets_.end())
|
889 |
|
|
cie_pointer = *find_cie;
|
890 |
|
|
else
|
891 |
|
|
{
|
892 |
|
|
// See if we already saw this CIE in this object file.
|
893 |
|
|
for (New_cies::const_iterator pc = new_cies->begin();
|
894 |
|
|
pc != new_cies->end();
|
895 |
|
|
++pc)
|
896 |
|
|
{
|
897 |
|
|
if (*(pc->first) == cie)
|
898 |
|
|
{
|
899 |
|
|
cie_pointer = pc->first;
|
900 |
|
|
break;
|
901 |
|
|
}
|
902 |
|
|
}
|
903 |
|
|
}
|
904 |
|
|
}
|
905 |
|
|
|
906 |
|
|
if (cie_pointer == NULL)
|
907 |
|
|
{
|
908 |
|
|
cie_pointer = new Cie(cie);
|
909 |
|
|
new_cies->push_back(std::make_pair(cie_pointer, mergeable));
|
910 |
|
|
}
|
911 |
|
|
else
|
912 |
|
|
{
|
913 |
|
|
// We are deleting this CIE. Record that in our mapping from
|
914 |
|
|
// input sections to the output section. At this point we don't
|
915 |
|
|
// know for sure that we are doing a special mapping for this
|
916 |
|
|
// input section, but that's OK--if we don't do a special
|
917 |
|
|
// mapping, nobody will ever ask for the mapping we add here.
|
918 |
|
|
this->merge_map_.add_mapping(object, shndx, (pcie - 8) - pcontents,
|
919 |
|
|
pcieend - (pcie - 8), -1);
|
920 |
|
|
}
|
921 |
|
|
|
922 |
|
|
// Record this CIE plus the offset in the input section.
|
923 |
|
|
cies->insert(std::make_pair(pcie - pcontents, cie_pointer));
|
924 |
|
|
|
925 |
|
|
return true;
|
926 |
|
|
}
|
927 |
|
|
|
928 |
|
|
// Read an FDE. Return false if we can't parse the information.
|
929 |
|
|
|
930 |
|
|
template<int size, bool big_endian>
|
931 |
|
|
bool
|
932 |
|
|
Eh_frame::read_fde(Sized_relobj<size, big_endian>* object,
|
933 |
|
|
unsigned int shndx,
|
934 |
|
|
const unsigned char* symbols,
|
935 |
|
|
section_size_type symbols_size,
|
936 |
|
|
const unsigned char* pcontents,
|
937 |
|
|
unsigned int offset,
|
938 |
|
|
const unsigned char* pfde,
|
939 |
|
|
const unsigned char *pfdeend,
|
940 |
|
|
Track_relocs<size, big_endian>* relocs,
|
941 |
|
|
Offsets_to_cie* cies)
|
942 |
|
|
{
|
943 |
|
|
// OFFSET is the distance between the 4 bytes before PFDE to the
|
944 |
|
|
// start of the CIE. The offset we recorded for the CIE is 8 bytes
|
945 |
|
|
// after the start of the CIE--after the length and the zero tag.
|
946 |
|
|
unsigned int cie_offset = (pfde - 4 - pcontents) - offset + 8;
|
947 |
|
|
Offsets_to_cie::const_iterator pcie = cies->find(cie_offset);
|
948 |
|
|
if (pcie == cies->end())
|
949 |
|
|
return false;
|
950 |
|
|
Cie* cie = pcie->second;
|
951 |
|
|
|
952 |
|
|
// The FDE should start with a reloc to the start of the code which
|
953 |
|
|
// it describes.
|
954 |
|
|
if (relocs->advance(pfde - pcontents) > 0)
|
955 |
|
|
return false;
|
956 |
|
|
|
957 |
|
|
if (relocs->next_offset() != pfde - pcontents)
|
958 |
|
|
return false;
|
959 |
|
|
|
960 |
|
|
unsigned int symndx = relocs->next_symndx();
|
961 |
|
|
if (symndx == -1U)
|
962 |
|
|
return false;
|
963 |
|
|
|
964 |
|
|
// There can be another reloc in the FDE, if the CIE specifies an
|
965 |
|
|
// LSDA (language specific data area). We currently don't care. We
|
966 |
|
|
// will care later if we want to optimize the LSDA from an absolute
|
967 |
|
|
// pointer to a PC relative offset when generating a shared library.
|
968 |
|
|
relocs->advance(pfdeend - pcontents);
|
969 |
|
|
|
970 |
|
|
unsigned int fde_shndx;
|
971 |
|
|
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
|
972 |
|
|
if (symndx >= symbols_size / sym_size)
|
973 |
|
|
return false;
|
974 |
|
|
elfcpp::Sym<size, big_endian> sym(symbols + symndx * sym_size);
|
975 |
|
|
bool is_ordinary;
|
976 |
|
|
fde_shndx = object->adjust_sym_shndx(symndx, sym.get_st_shndx(),
|
977 |
|
|
&is_ordinary);
|
978 |
|
|
|
979 |
|
|
if (is_ordinary
|
980 |
|
|
&& fde_shndx != elfcpp::SHN_UNDEF
|
981 |
|
|
&& fde_shndx < object->shnum()
|
982 |
|
|
&& !object->is_section_included(fde_shndx))
|
983 |
|
|
{
|
984 |
|
|
// This FDE applies to a section which we are discarding. We
|
985 |
|
|
// can discard this FDE.
|
986 |
|
|
this->merge_map_.add_mapping(object, shndx, (pfde - 8) - pcontents,
|
987 |
|
|
pfdeend - (pfde - 8), -1);
|
988 |
|
|
return true;
|
989 |
|
|
}
|
990 |
|
|
|
991 |
|
|
cie->add_fde(new Fde(object, shndx, (pfde - 8) - pcontents,
|
992 |
|
|
pfde, pfdeend - pfde));
|
993 |
|
|
|
994 |
|
|
return true;
|
995 |
|
|
}
|
996 |
|
|
|
997 |
|
|
// Return the number of FDEs.
|
998 |
|
|
|
999 |
|
|
unsigned int
|
1000 |
|
|
Eh_frame::fde_count() const
|
1001 |
|
|
{
|
1002 |
|
|
unsigned int ret = 0;
|
1003 |
|
|
for (Unmergeable_cie_offsets::const_iterator p =
|
1004 |
|
|
this->unmergeable_cie_offsets_.begin();
|
1005 |
|
|
p != this->unmergeable_cie_offsets_.end();
|
1006 |
|
|
++p)
|
1007 |
|
|
ret += (*p)->fde_count();
|
1008 |
|
|
for (Cie_offsets::const_iterator p = this->cie_offsets_.begin();
|
1009 |
|
|
p != this->cie_offsets_.end();
|
1010 |
|
|
++p)
|
1011 |
|
|
ret += (*p)->fde_count();
|
1012 |
|
|
return ret;
|
1013 |
|
|
}
|
1014 |
|
|
|
1015 |
|
|
// Set the final data size.
|
1016 |
|
|
|
1017 |
|
|
void
|
1018 |
|
|
Eh_frame::set_final_data_size()
|
1019 |
|
|
{
|
1020 |
|
|
// We can be called more than once if Layout::set_segment_offsets
|
1021 |
|
|
// finds a better mapping. We don't want to add all the mappings
|
1022 |
|
|
// again.
|
1023 |
|
|
if (this->mappings_are_done_)
|
1024 |
|
|
{
|
1025 |
|
|
this->set_data_size(this->final_data_size_);
|
1026 |
|
|
return;
|
1027 |
|
|
}
|
1028 |
|
|
|
1029 |
|
|
section_offset_type output_offset = 0;
|
1030 |
|
|
|
1031 |
|
|
for (Unmergeable_cie_offsets::iterator p =
|
1032 |
|
|
this->unmergeable_cie_offsets_.begin();
|
1033 |
|
|
p != this->unmergeable_cie_offsets_.end();
|
1034 |
|
|
++p)
|
1035 |
|
|
output_offset = (*p)->set_output_offset(output_offset,
|
1036 |
|
|
this->addralign(),
|
1037 |
|
|
&this->merge_map_);
|
1038 |
|
|
|
1039 |
|
|
for (Cie_offsets::iterator p = this->cie_offsets_.begin();
|
1040 |
|
|
p != this->cie_offsets_.end();
|
1041 |
|
|
++p)
|
1042 |
|
|
output_offset = (*p)->set_output_offset(output_offset,
|
1043 |
|
|
this->addralign(),
|
1044 |
|
|
&this->merge_map_);
|
1045 |
|
|
|
1046 |
|
|
this->mappings_are_done_ = true;
|
1047 |
|
|
this->final_data_size_ = output_offset;
|
1048 |
|
|
|
1049 |
|
|
gold_assert((output_offset & (this->addralign() - 1)) == 0);
|
1050 |
|
|
this->set_data_size(output_offset);
|
1051 |
|
|
}
|
1052 |
|
|
|
1053 |
|
|
// Return an output offset for an input offset.
|
1054 |
|
|
|
1055 |
|
|
bool
|
1056 |
|
|
Eh_frame::do_output_offset(const Relobj* object, unsigned int shndx,
|
1057 |
|
|
section_offset_type offset,
|
1058 |
|
|
section_offset_type* poutput) const
|
1059 |
|
|
{
|
1060 |
|
|
return this->merge_map_.get_output_offset(object, shndx, offset, poutput);
|
1061 |
|
|
}
|
1062 |
|
|
|
1063 |
|
|
// Return whether this is the merge section for an input section.
|
1064 |
|
|
|
1065 |
|
|
bool
|
1066 |
|
|
Eh_frame::do_is_merge_section_for(const Relobj* object,
|
1067 |
|
|
unsigned int shndx) const
|
1068 |
|
|
{
|
1069 |
|
|
return this->merge_map_.is_merge_section_for(object, shndx);
|
1070 |
|
|
}
|
1071 |
|
|
|
1072 |
|
|
// Write the data to the output file.
|
1073 |
|
|
|
1074 |
|
|
void
|
1075 |
|
|
Eh_frame::do_write(Output_file* of)
|
1076 |
|
|
{
|
1077 |
|
|
const off_t offset = this->offset();
|
1078 |
|
|
const off_t oview_size = this->data_size();
|
1079 |
|
|
unsigned char* const oview = of->get_output_view(offset, oview_size);
|
1080 |
|
|
|
1081 |
|
|
switch (parameters->size_and_endianness())
|
1082 |
|
|
{
|
1083 |
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
1084 |
|
|
case Parameters::TARGET_32_LITTLE:
|
1085 |
|
|
this->do_sized_write<32, false>(oview);
|
1086 |
|
|
break;
|
1087 |
|
|
#endif
|
1088 |
|
|
#ifdef HAVE_TARGET_32_BIG
|
1089 |
|
|
case Parameters::TARGET_32_BIG:
|
1090 |
|
|
this->do_sized_write<32, true>(oview);
|
1091 |
|
|
break;
|
1092 |
|
|
#endif
|
1093 |
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
1094 |
|
|
case Parameters::TARGET_64_LITTLE:
|
1095 |
|
|
this->do_sized_write<64, false>(oview);
|
1096 |
|
|
break;
|
1097 |
|
|
#endif
|
1098 |
|
|
#ifdef HAVE_TARGET_64_BIG
|
1099 |
|
|
case Parameters::TARGET_64_BIG:
|
1100 |
|
|
this->do_sized_write<64, true>(oview);
|
1101 |
|
|
break;
|
1102 |
|
|
#endif
|
1103 |
|
|
default:
|
1104 |
|
|
gold_unreachable();
|
1105 |
|
|
}
|
1106 |
|
|
|
1107 |
|
|
of->write_output_view(offset, oview_size, oview);
|
1108 |
|
|
}
|
1109 |
|
|
|
1110 |
|
|
// Write the data to the output file--template version.
|
1111 |
|
|
|
1112 |
|
|
template<int size, bool big_endian>
|
1113 |
|
|
void
|
1114 |
|
|
Eh_frame::do_sized_write(unsigned char* oview)
|
1115 |
|
|
{
|
1116 |
|
|
unsigned int addralign = this->addralign();
|
1117 |
|
|
section_offset_type o = 0;
|
1118 |
|
|
for (Unmergeable_cie_offsets::iterator p =
|
1119 |
|
|
this->unmergeable_cie_offsets_.begin();
|
1120 |
|
|
p != this->unmergeable_cie_offsets_.end();
|
1121 |
|
|
++p)
|
1122 |
|
|
o = (*p)->write<size, big_endian>(oview, o, addralign,
|
1123 |
|
|
this->eh_frame_hdr_);
|
1124 |
|
|
for (Cie_offsets::iterator p = this->cie_offsets_.begin();
|
1125 |
|
|
p != this->cie_offsets_.end();
|
1126 |
|
|
++p)
|
1127 |
|
|
o = (*p)->write<size, big_endian>(oview, o, addralign,
|
1128 |
|
|
this->eh_frame_hdr_);
|
1129 |
|
|
}
|
1130 |
|
|
|
1131 |
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
1132 |
|
|
template
|
1133 |
|
|
bool
|
1134 |
|
|
Eh_frame::add_ehframe_input_section<32, false>(
|
1135 |
|
|
Sized_relobj<32, false>* object,
|
1136 |
|
|
const unsigned char* symbols,
|
1137 |
|
|
section_size_type symbols_size,
|
1138 |
|
|
const unsigned char* symbol_names,
|
1139 |
|
|
section_size_type symbol_names_size,
|
1140 |
|
|
unsigned int shndx,
|
1141 |
|
|
unsigned int reloc_shndx,
|
1142 |
|
|
unsigned int reloc_type);
|
1143 |
|
|
#endif
|
1144 |
|
|
|
1145 |
|
|
#ifdef HAVE_TARGET_32_BIG
|
1146 |
|
|
template
|
1147 |
|
|
bool
|
1148 |
|
|
Eh_frame::add_ehframe_input_section<32, true>(
|
1149 |
|
|
Sized_relobj<32, true>* object,
|
1150 |
|
|
const unsigned char* symbols,
|
1151 |
|
|
section_size_type symbols_size,
|
1152 |
|
|
const unsigned char* symbol_names,
|
1153 |
|
|
section_size_type symbol_names_size,
|
1154 |
|
|
unsigned int shndx,
|
1155 |
|
|
unsigned int reloc_shndx,
|
1156 |
|
|
unsigned int reloc_type);
|
1157 |
|
|
#endif
|
1158 |
|
|
|
1159 |
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
1160 |
|
|
template
|
1161 |
|
|
bool
|
1162 |
|
|
Eh_frame::add_ehframe_input_section<64, false>(
|
1163 |
|
|
Sized_relobj<64, false>* object,
|
1164 |
|
|
const unsigned char* symbols,
|
1165 |
|
|
section_size_type symbols_size,
|
1166 |
|
|
const unsigned char* symbol_names,
|
1167 |
|
|
section_size_type symbol_names_size,
|
1168 |
|
|
unsigned int shndx,
|
1169 |
|
|
unsigned int reloc_shndx,
|
1170 |
|
|
unsigned int reloc_type);
|
1171 |
|
|
#endif
|
1172 |
|
|
|
1173 |
|
|
#ifdef HAVE_TARGET_64_BIG
|
1174 |
|
|
template
|
1175 |
|
|
bool
|
1176 |
|
|
Eh_frame::add_ehframe_input_section<64, true>(
|
1177 |
|
|
Sized_relobj<64, true>* object,
|
1178 |
|
|
const unsigned char* symbols,
|
1179 |
|
|
section_size_type symbols_size,
|
1180 |
|
|
const unsigned char* symbol_names,
|
1181 |
|
|
section_size_type symbol_names_size,
|
1182 |
|
|
unsigned int shndx,
|
1183 |
|
|
unsigned int reloc_shndx,
|
1184 |
|
|
unsigned int reloc_type);
|
1185 |
|
|
#endif
|
1186 |
|
|
|
1187 |
|
|
} // End namespace gold.
|