6463 lines
198 KiB
C++
6463 lines
198 KiB
C++
// layout.cc -- lay out output file sections for gold
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// Copyright (C) 2006-2022 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 <cerrno>
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#include <cstring>
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#include <algorithm>
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#include <iostream>
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#include <fstream>
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#include <utility>
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#include <fcntl.h>
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#include <fnmatch.h>
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#include <unistd.h>
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#include "libiberty.h"
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#include "md5.h"
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#include "sha1.h"
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#ifdef __MINGW32__
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#include <windows.h>
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#include <rpcdce.h>
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#endif
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#include "parameters.h"
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#include "options.h"
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#include "mapfile.h"
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#include "script.h"
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#include "script-sections.h"
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#include "output.h"
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#include "symtab.h"
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#include "dynobj.h"
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#include "ehframe.h"
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#include "gdb-index.h"
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#include "compressed_output.h"
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#include "reduced_debug_output.h"
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#include "object.h"
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#include "reloc.h"
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#include "descriptors.h"
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#include "plugin.h"
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#include "incremental.h"
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#include "layout.h"
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namespace gold
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{
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// Class Free_list.
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// The total number of free lists used.
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unsigned int Free_list::num_lists = 0;
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// The total number of free list nodes used.
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unsigned int Free_list::num_nodes = 0;
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// The total number of calls to Free_list::remove.
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unsigned int Free_list::num_removes = 0;
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// The total number of nodes visited during calls to Free_list::remove.
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unsigned int Free_list::num_remove_visits = 0;
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// The total number of calls to Free_list::allocate.
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unsigned int Free_list::num_allocates = 0;
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// The total number of nodes visited during calls to Free_list::allocate.
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unsigned int Free_list::num_allocate_visits = 0;
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// Initialize the free list. Creates a single free list node that
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// describes the entire region of length LEN. If EXTEND is true,
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// allocate() is allowed to extend the region beyond its initial
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// length.
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void
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Free_list::init(off_t len, bool extend)
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{
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this->list_.push_front(Free_list_node(0, len));
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this->last_remove_ = this->list_.begin();
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this->extend_ = extend;
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this->length_ = len;
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++Free_list::num_lists;
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++Free_list::num_nodes;
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}
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// Remove a chunk from the free list. Because we start with a single
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// node that covers the entire section, and remove chunks from it one
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// at a time, we do not need to coalesce chunks or handle cases that
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// span more than one free node. We expect to remove chunks from the
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// free list in order, and we expect to have only a few chunks of free
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// space left (corresponding to files that have changed since the last
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// incremental link), so a simple linear list should provide sufficient
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// performance.
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void
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Free_list::remove(off_t start, off_t end)
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{
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if (start == end)
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return;
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gold_assert(start < end);
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++Free_list::num_removes;
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Iterator p = this->last_remove_;
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if (p->start_ > start)
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p = this->list_.begin();
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for (; p != this->list_.end(); ++p)
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{
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++Free_list::num_remove_visits;
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// Find a node that wholly contains the indicated region.
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if (p->start_ <= start && p->end_ >= end)
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{
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// Case 1: the indicated region spans the whole node.
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// Add some fuzz to avoid creating tiny free chunks.
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if (p->start_ + 3 >= start && p->end_ <= end + 3)
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p = this->list_.erase(p);
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// Case 2: remove a chunk from the start of the node.
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else if (p->start_ + 3 >= start)
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p->start_ = end;
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// Case 3: remove a chunk from the end of the node.
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else if (p->end_ <= end + 3)
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p->end_ = start;
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// Case 4: remove a chunk from the middle, and split
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// the node into two.
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else
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{
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Free_list_node newnode(p->start_, start);
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p->start_ = end;
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this->list_.insert(p, newnode);
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++Free_list::num_nodes;
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}
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this->last_remove_ = p;
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return;
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}
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}
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// Did not find a node containing the given chunk. This could happen
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// because a small chunk was already removed due to the fuzz.
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gold_debug(DEBUG_INCREMENTAL,
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"Free_list::remove(%d,%d) not found",
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static_cast<int>(start), static_cast<int>(end));
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}
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// Allocate a chunk of size LEN from the free list. Returns -1ULL
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// if a sufficiently large chunk of free space is not found.
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// We use a simple first-fit algorithm.
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off_t
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Free_list::allocate(off_t len, uint64_t align, off_t minoff)
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{
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gold_debug(DEBUG_INCREMENTAL,
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"Free_list::allocate(%08lx, %d, %08lx)",
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static_cast<long>(len), static_cast<int>(align),
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static_cast<long>(minoff));
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if (len == 0)
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return align_address(minoff, align);
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++Free_list::num_allocates;
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// We usually want to drop free chunks smaller than 4 bytes.
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// If we need to guarantee a minimum hole size, though, we need
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// to keep track of all free chunks.
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const int fuzz = this->min_hole_ > 0 ? 0 : 3;
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for (Iterator p = this->list_.begin(); p != this->list_.end(); ++p)
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{
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++Free_list::num_allocate_visits;
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off_t start = p->start_ > minoff ? p->start_ : minoff;
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start = align_address(start, align);
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off_t end = start + len;
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if (end > p->end_ && p->end_ == this->length_ && this->extend_)
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{
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this->length_ = end;
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p->end_ = end;
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}
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if (end == p->end_ || (end <= p->end_ - this->min_hole_))
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{
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if (p->start_ + fuzz >= start && p->end_ <= end + fuzz)
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this->list_.erase(p);
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else if (p->start_ + fuzz >= start)
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p->start_ = end;
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else if (p->end_ <= end + fuzz)
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p->end_ = start;
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else
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{
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Free_list_node newnode(p->start_, start);
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p->start_ = end;
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this->list_.insert(p, newnode);
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++Free_list::num_nodes;
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}
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return start;
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}
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}
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if (this->extend_)
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{
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off_t start = align_address(this->length_, align);
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this->length_ = start + len;
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return start;
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}
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return -1;
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}
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// Dump the free list (for debugging).
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void
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Free_list::dump()
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{
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gold_info("Free list:\n start end length\n");
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for (Iterator p = this->list_.begin(); p != this->list_.end(); ++p)
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gold_info(" %08lx %08lx %08lx", static_cast<long>(p->start_),
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static_cast<long>(p->end_),
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static_cast<long>(p->end_ - p->start_));
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}
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// Print the statistics for the free lists.
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void
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Free_list::print_stats()
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{
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fprintf(stderr, _("%s: total free lists: %u\n"),
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program_name, Free_list::num_lists);
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fprintf(stderr, _("%s: total free list nodes: %u\n"),
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program_name, Free_list::num_nodes);
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fprintf(stderr, _("%s: calls to Free_list::remove: %u\n"),
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program_name, Free_list::num_removes);
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fprintf(stderr, _("%s: nodes visited: %u\n"),
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program_name, Free_list::num_remove_visits);
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fprintf(stderr, _("%s: calls to Free_list::allocate: %u\n"),
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program_name, Free_list::num_allocates);
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fprintf(stderr, _("%s: nodes visited: %u\n"),
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program_name, Free_list::num_allocate_visits);
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}
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// A Hash_task computes the MD5 checksum of an array of char.
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class Hash_task : public Task
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{
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public:
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Hash_task(Output_file* of,
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size_t offset,
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size_t size,
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unsigned char* dst,
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Task_token* final_blocker)
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: of_(of), offset_(offset), size_(size), dst_(dst),
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final_blocker_(final_blocker)
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{ }
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void
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run(Workqueue*)
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{
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const unsigned char* iv =
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this->of_->get_input_view(this->offset_, this->size_);
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md5_buffer(reinterpret_cast<const char*>(iv), this->size_, this->dst_);
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this->of_->free_input_view(this->offset_, this->size_, iv);
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}
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Task_token*
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is_runnable()
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{ return NULL; }
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// Unblock FINAL_BLOCKER_ when done.
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void
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locks(Task_locker* tl)
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{ tl->add(this, this->final_blocker_); }
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std::string
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get_name() const
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{ return "Hash_task"; }
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private:
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Output_file* of_;
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const size_t offset_;
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const size_t size_;
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unsigned char* const dst_;
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Task_token* const final_blocker_;
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};
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// Layout::Relaxation_debug_check methods.
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// Check that sections and special data are in reset states.
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// We do not save states for Output_sections and special Output_data.
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// So we check that they have not assigned any addresses or offsets.
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// clean_up_after_relaxation simply resets their addresses and offsets.
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void
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Layout::Relaxation_debug_check::check_output_data_for_reset_values(
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const Layout::Section_list& sections,
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const Layout::Data_list& special_outputs,
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const Layout::Data_list& relax_outputs)
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{
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for(Layout::Section_list::const_iterator p = sections.begin();
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p != sections.end();
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++p)
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gold_assert((*p)->address_and_file_offset_have_reset_values());
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for(Layout::Data_list::const_iterator p = special_outputs.begin();
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p != special_outputs.end();
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++p)
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gold_assert((*p)->address_and_file_offset_have_reset_values());
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gold_assert(relax_outputs.empty());
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}
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// Save information of SECTIONS for checking later.
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void
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Layout::Relaxation_debug_check::read_sections(
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const Layout::Section_list& sections)
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{
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for(Layout::Section_list::const_iterator p = sections.begin();
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p != sections.end();
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++p)
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{
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Output_section* os = *p;
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Section_info info;
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info.output_section = os;
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info.address = os->is_address_valid() ? os->address() : 0;
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info.data_size = os->is_data_size_valid() ? os->data_size() : -1;
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info.offset = os->is_offset_valid()? os->offset() : -1 ;
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this->section_infos_.push_back(info);
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}
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}
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// Verify SECTIONS using previously recorded information.
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void
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Layout::Relaxation_debug_check::verify_sections(
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const Layout::Section_list& sections)
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{
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size_t i = 0;
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for(Layout::Section_list::const_iterator p = sections.begin();
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p != sections.end();
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++p, ++i)
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{
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Output_section* os = *p;
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uint64_t address = os->is_address_valid() ? os->address() : 0;
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off_t data_size = os->is_data_size_valid() ? os->data_size() : -1;
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off_t offset = os->is_offset_valid()? os->offset() : -1 ;
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if (i >= this->section_infos_.size())
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{
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gold_fatal("Section_info of %s missing.\n", os->name());
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}
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const Section_info& info = this->section_infos_[i];
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if (os != info.output_section)
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gold_fatal("Section order changed. Expecting %s but see %s\n",
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info.output_section->name(), os->name());
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if (address != info.address
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|| data_size != info.data_size
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|| offset != info.offset)
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gold_fatal("Section %s changed.\n", os->name());
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}
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}
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// Layout_task_runner methods.
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// Lay out the sections. This is called after all the input objects
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// have been read.
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void
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Layout_task_runner::run(Workqueue* workqueue, const Task* task)
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{
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// See if any of the input definitions violate the One Definition Rule.
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// TODO: if this is too slow, do this as a task, rather than inline.
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this->symtab_->detect_odr_violations(task, this->options_.output_file_name());
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Layout* layout = this->layout_;
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off_t file_size = layout->finalize(this->input_objects_,
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this->symtab_,
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this->target_,
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task);
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// Now we know the final size of the output file and we know where
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// each piece of information goes.
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if (this->mapfile_ != NULL)
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{
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this->mapfile_->print_discarded_sections(this->input_objects_);
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layout->print_to_mapfile(this->mapfile_);
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}
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Output_file* of;
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if (layout->incremental_base() == NULL)
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{
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of = new Output_file(parameters->options().output_file_name());
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if (this->options_.oformat_enum() != General_options::OBJECT_FORMAT_ELF)
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of->set_is_temporary();
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of->open(file_size);
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}
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else
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{
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of = layout->incremental_base()->output_file();
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// Apply the incremental relocations for symbols whose values
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// have changed. We do this before we resize the file and start
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// writing anything else to it, so that we can read the old
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// incremental information from the file before (possibly)
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// overwriting it.
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if (parameters->incremental_update())
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layout->incremental_base()->apply_incremental_relocs(this->symtab_,
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this->layout_,
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of);
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of->resize(file_size);
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}
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// Queue up the final set of tasks.
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gold::queue_final_tasks(this->options_, this->input_objects_,
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this->symtab_, layout, workqueue, of);
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}
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// Layout methods.
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Layout::Layout(int number_of_input_files, Script_options* script_options)
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: number_of_input_files_(number_of_input_files),
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script_options_(script_options),
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namepool_(),
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sympool_(),
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dynpool_(),
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signatures_(),
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section_name_map_(),
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segment_list_(),
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section_list_(),
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unattached_section_list_(),
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special_output_list_(),
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relax_output_list_(),
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section_headers_(NULL),
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tls_segment_(NULL),
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relro_segment_(NULL),
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interp_segment_(NULL),
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increase_relro_(0),
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symtab_section_(NULL),
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symtab_xindex_(NULL),
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dynsym_section_(NULL),
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dynsym_xindex_(NULL),
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dynamic_section_(NULL),
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dynamic_symbol_(NULL),
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dynamic_data_(NULL),
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eh_frame_section_(NULL),
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eh_frame_data_(NULL),
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added_eh_frame_data_(false),
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eh_frame_hdr_section_(NULL),
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gdb_index_data_(NULL),
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build_id_note_(NULL),
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debug_abbrev_(NULL),
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debug_info_(NULL),
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group_signatures_(),
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output_file_size_(-1),
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have_added_input_section_(false),
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sections_are_attached_(false),
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input_requires_executable_stack_(false),
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input_with_gnu_stack_note_(false),
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input_without_gnu_stack_note_(false),
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has_static_tls_(false),
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any_postprocessing_sections_(false),
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resized_signatures_(false),
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have_stabstr_section_(false),
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section_ordering_specified_(false),
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unique_segment_for_sections_specified_(false),
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incremental_inputs_(NULL),
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record_output_section_data_from_script_(false),
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lto_slim_object_(false),
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script_output_section_data_list_(),
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segment_states_(NULL),
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relaxation_debug_check_(NULL),
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section_order_map_(),
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section_segment_map_(),
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input_section_position_(),
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input_section_glob_(),
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incremental_base_(NULL),
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free_list_(),
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gnu_properties_()
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{
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// Make space for more than enough segments for a typical file.
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// This is just for efficiency--it's OK if we wind up needing more.
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this->segment_list_.reserve(12);
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// We expect two unattached Output_data objects: the file header and
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// the segment headers.
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this->special_output_list_.reserve(2);
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// Initialize structure needed for an incremental build.
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if (parameters->incremental())
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this->incremental_inputs_ = new Incremental_inputs;
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// The section name pool is worth optimizing in all cases, because
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// it is small, but there are often overlaps due to .rel sections.
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this->namepool_.set_optimize();
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}
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// For incremental links, record the base file to be modified.
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void
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Layout::set_incremental_base(Incremental_binary* base)
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{
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this->incremental_base_ = base;
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this->free_list_.init(base->output_file()->filesize(), true);
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}
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// Hash a key we use to look up an output section mapping.
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size_t
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Layout::Hash_key::operator()(const Layout::Key& k) const
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{
|
|
return k.first + k.second.first + k.second.second;
|
|
}
|
|
|
|
// These are the debug sections that are actually used by gdb.
|
|
// Currently, we've checked versions of gdb up to and including 7.4.
|
|
// We only check the part of the name that follows ".debug_" or
|
|
// ".zdebug_".
|
|
|
|
static const char* gdb_sections[] =
|
|
{
|
|
"abbrev",
|
|
"addr", // Fission extension
|
|
// "aranges", // not used by gdb as of 7.4
|
|
"frame",
|
|
"gdb_scripts",
|
|
"info",
|
|
"types",
|
|
"line",
|
|
"loc",
|
|
"macinfo",
|
|
"macro",
|
|
// "pubnames", // not used by gdb as of 7.4
|
|
// "pubtypes", // not used by gdb as of 7.4
|
|
// "gnu_pubnames", // Fission extension
|
|
// "gnu_pubtypes", // Fission extension
|
|
"ranges",
|
|
"str",
|
|
"str_offsets",
|
|
};
|
|
|
|
// This is the minimum set of sections needed for line numbers.
|
|
|
|
static const char* lines_only_debug_sections[] =
|
|
{
|
|
"abbrev",
|
|
// "addr", // Fission extension
|
|
// "aranges", // not used by gdb as of 7.4
|
|
// "frame",
|
|
// "gdb_scripts",
|
|
"info",
|
|
// "types",
|
|
"line",
|
|
// "loc",
|
|
// "macinfo",
|
|
// "macro",
|
|
// "pubnames", // not used by gdb as of 7.4
|
|
// "pubtypes", // not used by gdb as of 7.4
|
|
// "gnu_pubnames", // Fission extension
|
|
// "gnu_pubtypes", // Fission extension
|
|
// "ranges",
|
|
"str",
|
|
"str_offsets", // Fission extension
|
|
};
|
|
|
|
// These sections are the DWARF fast-lookup tables, and are not needed
|
|
// when building a .gdb_index section.
|
|
|
|
static const char* gdb_fast_lookup_sections[] =
|
|
{
|
|
"aranges",
|
|
"pubnames",
|
|
"gnu_pubnames",
|
|
"pubtypes",
|
|
"gnu_pubtypes",
|
|
};
|
|
|
|
// Returns whether the given debug section is in the list of
|
|
// debug-sections-used-by-some-version-of-gdb. SUFFIX is the
|
|
// portion of the name following ".debug_" or ".zdebug_".
|
|
|
|
static inline bool
|
|
is_gdb_debug_section(const char* suffix)
|
|
{
|
|
// We can do this faster: binary search or a hashtable. But why bother?
|
|
for (size_t i = 0; i < sizeof(gdb_sections)/sizeof(*gdb_sections); ++i)
|
|
if (strcmp(suffix, gdb_sections[i]) == 0)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
// Returns whether the given section is needed for lines-only debugging.
|
|
|
|
static inline bool
|
|
is_lines_only_debug_section(const char* suffix)
|
|
{
|
|
// We can do this faster: binary search or a hashtable. But why bother?
|
|
for (size_t i = 0;
|
|
i < sizeof(lines_only_debug_sections)/sizeof(*lines_only_debug_sections);
|
|
++i)
|
|
if (strcmp(suffix, lines_only_debug_sections[i]) == 0)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
// Returns whether the given section is a fast-lookup section that
|
|
// will not be needed when building a .gdb_index section.
|
|
|
|
static inline bool
|
|
is_gdb_fast_lookup_section(const char* suffix)
|
|
{
|
|
// We can do this faster: binary search or a hashtable. But why bother?
|
|
for (size_t i = 0;
|
|
i < sizeof(gdb_fast_lookup_sections)/sizeof(*gdb_fast_lookup_sections);
|
|
++i)
|
|
if (strcmp(suffix, gdb_fast_lookup_sections[i]) == 0)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
// Sometimes we compress sections. This is typically done for
|
|
// sections that are not part of normal program execution (such as
|
|
// .debug_* sections), and where the readers of these sections know
|
|
// how to deal with compressed sections. This routine doesn't say for
|
|
// certain whether we'll compress -- it depends on commandline options
|
|
// as well -- just whether this section is a candidate for compression.
|
|
// (The Output_compressed_section class decides whether to compress
|
|
// a given section, and picks the name of the compressed section.)
|
|
|
|
static bool
|
|
is_compressible_debug_section(const char* secname)
|
|
{
|
|
return (is_prefix_of(".debug", secname));
|
|
}
|
|
|
|
// We may see compressed debug sections in input files. Return TRUE
|
|
// if this is the name of a compressed debug section.
|
|
|
|
bool
|
|
is_compressed_debug_section(const char* secname)
|
|
{
|
|
return (is_prefix_of(".zdebug", secname));
|
|
}
|
|
|
|
std::string
|
|
corresponding_uncompressed_section_name(std::string secname)
|
|
{
|
|
gold_assert(secname[0] == '.' && secname[1] == 'z');
|
|
std::string ret(".");
|
|
ret.append(secname, 2, std::string::npos);
|
|
return ret;
|
|
}
|
|
|
|
// Whether to include this section in the link.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Layout::include_section(Sized_relobj_file<size, big_endian>*, const char* name,
|
|
const elfcpp::Shdr<size, big_endian>& shdr)
|
|
{
|
|
if (!parameters->options().relocatable()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_EXCLUDE))
|
|
return false;
|
|
|
|
elfcpp::Elf_Word sh_type = shdr.get_sh_type();
|
|
|
|
if ((sh_type >= elfcpp::SHT_LOOS && sh_type <= elfcpp::SHT_HIOS)
|
|
|| (sh_type >= elfcpp::SHT_LOPROC && sh_type <= elfcpp::SHT_HIPROC))
|
|
return parameters->target().should_include_section(sh_type);
|
|
|
|
switch (sh_type)
|
|
{
|
|
case elfcpp::SHT_NULL:
|
|
case elfcpp::SHT_SYMTAB:
|
|
case elfcpp::SHT_DYNSYM:
|
|
case elfcpp::SHT_HASH:
|
|
case elfcpp::SHT_DYNAMIC:
|
|
case elfcpp::SHT_SYMTAB_SHNDX:
|
|
return false;
|
|
|
|
case elfcpp::SHT_STRTAB:
|
|
// Discard the sections which have special meanings in the ELF
|
|
// ABI. Keep others (e.g., .stabstr). We could also do this by
|
|
// checking the sh_link fields of the appropriate sections.
|
|
return (strcmp(name, ".dynstr") != 0
|
|
&& strcmp(name, ".strtab") != 0
|
|
&& strcmp(name, ".shstrtab") != 0);
|
|
|
|
case elfcpp::SHT_RELA:
|
|
case elfcpp::SHT_REL:
|
|
case elfcpp::SHT_GROUP:
|
|
// If we are emitting relocations these should be handled
|
|
// elsewhere.
|
|
gold_assert(!parameters->options().relocatable());
|
|
return false;
|
|
|
|
case elfcpp::SHT_PROGBITS:
|
|
if (parameters->options().strip_debug()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
if (is_debug_info_section(name))
|
|
return false;
|
|
}
|
|
if (parameters->options().strip_debug_non_line()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
// Debugging sections can only be recognized by name.
|
|
if (is_prefix_of(".debug_", name)
|
|
&& !is_lines_only_debug_section(name + 7))
|
|
return false;
|
|
if (is_prefix_of(".zdebug_", name)
|
|
&& !is_lines_only_debug_section(name + 8))
|
|
return false;
|
|
}
|
|
if (parameters->options().strip_debug_gdb()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
// Debugging sections can only be recognized by name.
|
|
if (is_prefix_of(".debug_", name)
|
|
&& !is_gdb_debug_section(name + 7))
|
|
return false;
|
|
if (is_prefix_of(".zdebug_", name)
|
|
&& !is_gdb_debug_section(name + 8))
|
|
return false;
|
|
}
|
|
if (parameters->options().gdb_index()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
// When building .gdb_index, we can strip .debug_pubnames,
|
|
// .debug_pubtypes, and .debug_aranges sections.
|
|
if (is_prefix_of(".debug_", name)
|
|
&& is_gdb_fast_lookup_section(name + 7))
|
|
return false;
|
|
if (is_prefix_of(".zdebug_", name)
|
|
&& is_gdb_fast_lookup_section(name + 8))
|
|
return false;
|
|
}
|
|
if (parameters->options().strip_lto_sections()
|
|
&& !parameters->options().relocatable()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
// Ignore LTO sections containing intermediate code.
|
|
if (is_prefix_of(".gnu.lto_", name))
|
|
return false;
|
|
}
|
|
// The GNU linker strips .gnu_debuglink sections, so we do too.
|
|
// This is a feature used to keep debugging information in
|
|
// separate files.
|
|
if (strcmp(name, ".gnu_debuglink") == 0)
|
|
return false;
|
|
return true;
|
|
|
|
default:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// Return an output section named NAME, or NULL if there is none.
|
|
|
|
Output_section*
|
|
Layout::find_output_section(const char* name) const
|
|
{
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
if (strcmp((*p)->name(), name) == 0)
|
|
return *p;
|
|
return NULL;
|
|
}
|
|
|
|
// Return an output segment of type TYPE, with segment flags SET set
|
|
// and segment flags CLEAR clear. Return NULL if there is none.
|
|
|
|
Output_segment*
|
|
Layout::find_output_segment(elfcpp::PT type, elfcpp::Elf_Word set,
|
|
elfcpp::Elf_Word clear) const
|
|
{
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
if (static_cast<elfcpp::PT>((*p)->type()) == type
|
|
&& ((*p)->flags() & set) == set
|
|
&& ((*p)->flags() & clear) == 0)
|
|
return *p;
|
|
return NULL;
|
|
}
|
|
|
|
// When we put a .ctors or .dtors section with more than one word into
|
|
// a .init_array or .fini_array section, we need to reverse the words
|
|
// in the .ctors/.dtors section. This is because .init_array executes
|
|
// constructors front to back, where .ctors executes them back to
|
|
// front, and vice-versa for .fini_array/.dtors. Although we do want
|
|
// to remap .ctors/.dtors into .init_array/.fini_array because it can
|
|
// be more efficient, we don't want to change the order in which
|
|
// constructors/destructors are run. This set just keeps track of
|
|
// these sections which need to be reversed. It is only changed by
|
|
// Layout::layout. It should be a private member of Layout, but that
|
|
// would require layout.h to #include object.h to get the definition
|
|
// of Section_id.
|
|
static Unordered_set<Section_id, Section_id_hash> ctors_sections_in_init_array;
|
|
|
|
// Return whether OBJECT/SHNDX is a .ctors/.dtors section mapped to a
|
|
// .init_array/.fini_array section.
|
|
|
|
bool
|
|
Layout::is_ctors_in_init_array(Relobj* relobj, unsigned int shndx) const
|
|
{
|
|
return (ctors_sections_in_init_array.find(Section_id(relobj, shndx))
|
|
!= ctors_sections_in_init_array.end());
|
|
}
|
|
|
|
// Return the output section to use for section NAME with type TYPE
|
|
// and section flags FLAGS. NAME must be canonicalized in the string
|
|
// pool, and NAME_KEY is the key. ORDER is where this should appear
|
|
// in the output sections. IS_RELRO is true for a relro section.
|
|
|
|
Output_section*
|
|
Layout::get_output_section(const char* name, Stringpool::Key name_key,
|
|
elfcpp::Elf_Word type, elfcpp::Elf_Xword flags,
|
|
Output_section_order order, bool is_relro)
|
|
{
|
|
elfcpp::Elf_Word lookup_type = type;
|
|
|
|
// For lookup purposes, treat INIT_ARRAY, FINI_ARRAY, and
|
|
// PREINIT_ARRAY like PROGBITS. This ensures that we combine
|
|
// .init_array, .fini_array, and .preinit_array sections by name
|
|
// whatever their type in the input file. We do this because the
|
|
// types are not always right in the input files.
|
|
if (lookup_type == elfcpp::SHT_INIT_ARRAY
|
|
|| lookup_type == elfcpp::SHT_FINI_ARRAY
|
|
|| lookup_type == elfcpp::SHT_PREINIT_ARRAY)
|
|
lookup_type = elfcpp::SHT_PROGBITS;
|
|
|
|
elfcpp::Elf_Xword lookup_flags = flags;
|
|
|
|
// Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
|
|
// read-write with read-only sections. Some other ELF linkers do
|
|
// not do this. FIXME: Perhaps there should be an option
|
|
// controlling this.
|
|
lookup_flags &= ~(elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR);
|
|
|
|
const Key key(name_key, std::make_pair(lookup_type, lookup_flags));
|
|
const std::pair<Key, Output_section*> v(key, NULL);
|
|
std::pair<Section_name_map::iterator, bool> ins(
|
|
this->section_name_map_.insert(v));
|
|
|
|
if (!ins.second)
|
|
return ins.first->second;
|
|
else
|
|
{
|
|
// This is the first time we've seen this name/type/flags
|
|
// combination. For compatibility with the GNU linker, we
|
|
// combine sections with contents and zero flags with sections
|
|
// with non-zero flags. This is a workaround for cases where
|
|
// assembler code forgets to set section flags. FIXME: Perhaps
|
|
// there should be an option to control this.
|
|
Output_section* os = NULL;
|
|
|
|
if (lookup_type == elfcpp::SHT_PROGBITS)
|
|
{
|
|
if (flags == 0)
|
|
{
|
|
Output_section* same_name = this->find_output_section(name);
|
|
if (same_name != NULL
|
|
&& (same_name->type() == elfcpp::SHT_PROGBITS
|
|
|| same_name->type() == elfcpp::SHT_INIT_ARRAY
|
|
|| same_name->type() == elfcpp::SHT_FINI_ARRAY
|
|
|| same_name->type() == elfcpp::SHT_PREINIT_ARRAY)
|
|
&& (same_name->flags() & elfcpp::SHF_TLS) == 0)
|
|
os = same_name;
|
|
}
|
|
else if ((flags & elfcpp::SHF_TLS) == 0)
|
|
{
|
|
elfcpp::Elf_Xword zero_flags = 0;
|
|
const Key zero_key(name_key, std::make_pair(lookup_type,
|
|
zero_flags));
|
|
Section_name_map::iterator p =
|
|
this->section_name_map_.find(zero_key);
|
|
if (p != this->section_name_map_.end())
|
|
os = p->second;
|
|
}
|
|
}
|
|
|
|
if (os == NULL)
|
|
os = this->make_output_section(name, type, flags, order, is_relro);
|
|
|
|
ins.first->second = os;
|
|
return os;
|
|
}
|
|
}
|
|
|
|
// Returns TRUE iff NAME (an input section from RELOBJ) will
|
|
// be mapped to an output section that should be KEPT.
|
|
|
|
bool
|
|
Layout::keep_input_section(const Relobj* relobj, const char* name)
|
|
{
|
|
if (! this->script_options_->saw_sections_clause())
|
|
return false;
|
|
|
|
Script_sections* ss = this->script_options_->script_sections();
|
|
const char* file_name = relobj == NULL ? NULL : relobj->name().c_str();
|
|
Output_section** output_section_slot;
|
|
Script_sections::Section_type script_section_type;
|
|
bool keep;
|
|
|
|
name = ss->output_section_name(file_name, name, &output_section_slot,
|
|
&script_section_type, &keep, true);
|
|
return name != NULL && keep;
|
|
}
|
|
|
|
// Clear the input section flags that should not be copied to the
|
|
// output section.
|
|
|
|
elfcpp::Elf_Xword
|
|
Layout::get_output_section_flags(elfcpp::Elf_Xword input_section_flags)
|
|
{
|
|
// Some flags in the input section should not be automatically
|
|
// copied to the output section.
|
|
input_section_flags &= ~ (elfcpp::SHF_INFO_LINK
|
|
| elfcpp::SHF_GROUP
|
|
| elfcpp::SHF_COMPRESSED
|
|
| elfcpp::SHF_MERGE
|
|
| elfcpp::SHF_STRINGS);
|
|
|
|
// We only clear the SHF_LINK_ORDER flag in for
|
|
// a non-relocatable link.
|
|
if (!parameters->options().relocatable())
|
|
input_section_flags &= ~elfcpp::SHF_LINK_ORDER;
|
|
|
|
return input_section_flags;
|
|
}
|
|
|
|
// Pick the output section to use for section NAME, in input file
|
|
// RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
|
|
// linker created section. IS_INPUT_SECTION is true if we are
|
|
// choosing an output section for an input section found in a input
|
|
// file. ORDER is where this section should appear in the output
|
|
// sections. IS_RELRO is true for a relro section. This will return
|
|
// NULL if the input section should be discarded. MATCH_INPUT_SPEC
|
|
// is true if the section name should be matched against input specs
|
|
// in a linker script.
|
|
|
|
Output_section*
|
|
Layout::choose_output_section(const Relobj* relobj, const char* name,
|
|
elfcpp::Elf_Word type, elfcpp::Elf_Xword flags,
|
|
bool is_input_section, Output_section_order order,
|
|
bool is_relro, bool is_reloc,
|
|
bool match_input_spec)
|
|
{
|
|
// We should not see any input sections after we have attached
|
|
// sections to segments.
|
|
gold_assert(!is_input_section || !this->sections_are_attached_);
|
|
|
|
flags = this->get_output_section_flags(flags);
|
|
|
|
if (this->script_options_->saw_sections_clause() && !is_reloc)
|
|
{
|
|
// We are using a SECTIONS clause, so the output section is
|
|
// chosen based only on the name.
|
|
|
|
Script_sections* ss = this->script_options_->script_sections();
|
|
const char* file_name = relobj == NULL ? NULL : relobj->name().c_str();
|
|
Output_section** output_section_slot;
|
|
Script_sections::Section_type script_section_type;
|
|
const char* orig_name = name;
|
|
bool keep;
|
|
name = ss->output_section_name(file_name, name, &output_section_slot,
|
|
&script_section_type, &keep,
|
|
match_input_spec);
|
|
|
|
if (name == NULL)
|
|
{
|
|
gold_debug(DEBUG_SCRIPT, _("Unable to create output section '%s' "
|
|
"because it is not allowed by the "
|
|
"SECTIONS clause of the linker script"),
|
|
orig_name);
|
|
// The SECTIONS clause says to discard this input section.
|
|
return NULL;
|
|
}
|
|
|
|
// We can only handle script section types ST_NONE and ST_NOLOAD.
|
|
switch (script_section_type)
|
|
{
|
|
case Script_sections::ST_NONE:
|
|
break;
|
|
case Script_sections::ST_NOLOAD:
|
|
flags &= elfcpp::SHF_ALLOC;
|
|
break;
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
|
|
// If this is an orphan section--one not mentioned in the linker
|
|
// script--then OUTPUT_SECTION_SLOT will be NULL, and we do the
|
|
// default processing below.
|
|
|
|
if (output_section_slot != NULL)
|
|
{
|
|
if (*output_section_slot != NULL)
|
|
{
|
|
(*output_section_slot)->update_flags_for_input_section(flags);
|
|
return *output_section_slot;
|
|
}
|
|
|
|
// We don't put sections found in the linker script into
|
|
// SECTION_NAME_MAP_. That keeps us from getting confused
|
|
// if an orphan section is mapped to a section with the same
|
|
// name as one in the linker script.
|
|
|
|
name = this->namepool_.add(name, false, NULL);
|
|
|
|
Output_section* os = this->make_output_section(name, type, flags,
|
|
order, is_relro);
|
|
|
|
os->set_found_in_sections_clause();
|
|
|
|
// Special handling for NOLOAD sections.
|
|
if (script_section_type == Script_sections::ST_NOLOAD)
|
|
{
|
|
os->set_is_noload();
|
|
|
|
// The constructor of Output_section sets addresses of non-ALLOC
|
|
// sections to 0 by default. We don't want that for NOLOAD
|
|
// sections even if they have no SHF_ALLOC flag.
|
|
if ((os->flags() & elfcpp::SHF_ALLOC) == 0
|
|
&& os->is_address_valid())
|
|
{
|
|
gold_assert(os->address() == 0
|
|
&& !os->is_offset_valid()
|
|
&& !os->is_data_size_valid());
|
|
os->reset_address_and_file_offset();
|
|
}
|
|
}
|
|
|
|
*output_section_slot = os;
|
|
return os;
|
|
}
|
|
}
|
|
|
|
// FIXME: Handle SHF_OS_NONCONFORMING somewhere.
|
|
|
|
size_t len = strlen(name);
|
|
std::string uncompressed_name;
|
|
|
|
// Compressed debug sections should be mapped to the corresponding
|
|
// uncompressed section.
|
|
if (is_compressed_debug_section(name))
|
|
{
|
|
uncompressed_name =
|
|
corresponding_uncompressed_section_name(std::string(name, len));
|
|
name = uncompressed_name.c_str();
|
|
len = uncompressed_name.length();
|
|
}
|
|
|
|
// Turn NAME from the name of the input section into the name of the
|
|
// output section.
|
|
if (is_input_section
|
|
&& !this->script_options_->saw_sections_clause()
|
|
&& !parameters->options().relocatable())
|
|
{
|
|
const char *orig_name = name;
|
|
name = parameters->target().output_section_name(relobj, name, &len);
|
|
if (name == NULL)
|
|
name = Layout::output_section_name(relobj, orig_name, &len);
|
|
}
|
|
|
|
Stringpool::Key name_key;
|
|
name = this->namepool_.add_with_length(name, len, true, &name_key);
|
|
|
|
// Find or make the output section. The output section is selected
|
|
// based on the section name, type, and flags.
|
|
return this->get_output_section(name, name_key, type, flags, order, is_relro);
|
|
}
|
|
|
|
// For incremental links, record the initial fixed layout of a section
|
|
// from the base file, and return a pointer to the Output_section.
|
|
|
|
template<int size, bool big_endian>
|
|
Output_section*
|
|
Layout::init_fixed_output_section(const char* name,
|
|
elfcpp::Shdr<size, big_endian>& shdr)
|
|
{
|
|
unsigned int sh_type = shdr.get_sh_type();
|
|
|
|
// We preserve the layout of PROGBITS, NOBITS, INIT_ARRAY, FINI_ARRAY,
|
|
// PRE_INIT_ARRAY, and NOTE sections.
|
|
// All others will be created from scratch and reallocated.
|
|
if (!can_incremental_update(sh_type))
|
|
return NULL;
|
|
|
|
// If we're generating a .gdb_index section, we need to regenerate
|
|
// it from scratch.
|
|
if (parameters->options().gdb_index()
|
|
&& sh_type == elfcpp::SHT_PROGBITS
|
|
&& strcmp(name, ".gdb_index") == 0)
|
|
return NULL;
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_Addr sh_addr = shdr.get_sh_addr();
|
|
typename elfcpp::Elf_types<size>::Elf_Off sh_offset = shdr.get_sh_offset();
|
|
typename elfcpp::Elf_types<size>::Elf_WXword sh_size = shdr.get_sh_size();
|
|
typename elfcpp::Elf_types<size>::Elf_WXword sh_flags =
|
|
this->get_output_section_flags(shdr.get_sh_flags());
|
|
typename elfcpp::Elf_types<size>::Elf_WXword sh_addralign =
|
|
shdr.get_sh_addralign();
|
|
|
|
// Make the output section.
|
|
Stringpool::Key name_key;
|
|
name = this->namepool_.add(name, true, &name_key);
|
|
Output_section* os = this->get_output_section(name, name_key, sh_type,
|
|
sh_flags, ORDER_INVALID, false);
|
|
os->set_fixed_layout(sh_addr, sh_offset, sh_size, sh_addralign);
|
|
if (sh_type != elfcpp::SHT_NOBITS)
|
|
this->free_list_.remove(sh_offset, sh_offset + sh_size);
|
|
return os;
|
|
}
|
|
|
|
// Return the index by which an input section should be ordered. This
|
|
// is used to sort some .text sections, for compatibility with GNU ld.
|
|
|
|
int
|
|
Layout::special_ordering_of_input_section(const char* name)
|
|
{
|
|
// The GNU linker has some special handling for some sections that
|
|
// wind up in the .text section. Sections that start with these
|
|
// prefixes must appear first, and must appear in the order listed
|
|
// here.
|
|
static const char* const text_section_sort[] =
|
|
{
|
|
".text.unlikely",
|
|
".text.exit",
|
|
".text.startup",
|
|
".text.hot",
|
|
".text.sorted"
|
|
};
|
|
|
|
for (size_t i = 0;
|
|
i < sizeof(text_section_sort) / sizeof(text_section_sort[0]);
|
|
i++)
|
|
if (is_prefix_of(text_section_sort[i], name))
|
|
return i;
|
|
|
|
return -1;
|
|
}
|
|
|
|
// Return the output section to use for input section SHNDX, with name
|
|
// NAME, with header HEADER, from object OBJECT. RELOC_SHNDX is the
|
|
// index of a relocation section which applies to this section, or 0
|
|
// if none, or -1U if more than one. RELOC_TYPE is the type of the
|
|
// relocation section if there is one. Set *OFF to the offset of this
|
|
// input section without the output section. Return NULL if the
|
|
// section should be discarded. Set *OFF to -1 if the section
|
|
// contents should not be written directly to the output file, but
|
|
// will instead receive special handling.
|
|
|
|
template<int size, bool big_endian>
|
|
Output_section*
|
|
Layout::layout(Sized_relobj_file<size, big_endian>* object, unsigned int shndx,
|
|
const char* name, const elfcpp::Shdr<size, big_endian>& shdr,
|
|
unsigned int sh_type, unsigned int reloc_shndx,
|
|
unsigned int, off_t* off)
|
|
{
|
|
*off = 0;
|
|
|
|
if (!this->include_section(object, name, shdr))
|
|
return NULL;
|
|
|
|
// In a relocatable link a grouped section must not be combined with
|
|
// any other sections.
|
|
Output_section* os;
|
|
if (parameters->options().relocatable()
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_GROUP) != 0)
|
|
{
|
|
// Some flags in the input section should not be automatically
|
|
// copied to the output section.
|
|
elfcpp::Elf_Xword sh_flags = (shdr.get_sh_flags()
|
|
& ~ elfcpp::SHF_COMPRESSED);
|
|
name = this->namepool_.add(name, true, NULL);
|
|
os = this->make_output_section(name, sh_type, sh_flags, ORDER_INVALID,
|
|
false);
|
|
}
|
|
else
|
|
{
|
|
// Get the section flags and mask out any flags that do not
|
|
// take part in section matching.
|
|
elfcpp::Elf_Xword sh_flags
|
|
= (this->get_output_section_flags(shdr.get_sh_flags())
|
|
& ~object->osabi().ignored_sh_flags());
|
|
|
|
// All ".text.unlikely.*" sections can be moved to a unique
|
|
// segment with --text-unlikely-segment option.
|
|
bool text_unlikely_segment
|
|
= (parameters->options().text_unlikely_segment()
|
|
&& is_prefix_of(".text.unlikely",
|
|
object->section_name(shndx).c_str()));
|
|
if (text_unlikely_segment)
|
|
{
|
|
Stringpool::Key name_key;
|
|
const char* os_name = this->namepool_.add(".text.unlikely", true,
|
|
&name_key);
|
|
os = this->get_output_section(os_name, name_key, sh_type, sh_flags,
|
|
ORDER_INVALID, false);
|
|
// Map this output section to a unique segment. This is done to
|
|
// separate "text" that is not likely to be executed from "text"
|
|
// that is likely executed.
|
|
os->set_is_unique_segment();
|
|
}
|
|
else
|
|
{
|
|
// Plugins can choose to place one or more subsets of sections in
|
|
// unique segments and this is done by mapping these section subsets
|
|
// to unique output sections. Check if this section needs to be
|
|
// remapped to a unique output section.
|
|
Section_segment_map::iterator it
|
|
= this->section_segment_map_.find(Const_section_id(object, shndx));
|
|
if (it == this->section_segment_map_.end())
|
|
{
|
|
os = this->choose_output_section(object, name, sh_type,
|
|
sh_flags, true, ORDER_INVALID,
|
|
false, false, true);
|
|
}
|
|
else
|
|
{
|
|
// We know the name of the output section, directly call
|
|
// get_output_section here by-passing choose_output_section.
|
|
const char* os_name = it->second->name;
|
|
Stringpool::Key name_key;
|
|
os_name = this->namepool_.add(os_name, true, &name_key);
|
|
os = this->get_output_section(os_name, name_key, sh_type,
|
|
sh_flags, ORDER_INVALID, false);
|
|
if (!os->is_unique_segment())
|
|
{
|
|
os->set_is_unique_segment();
|
|
os->set_extra_segment_flags(it->second->flags);
|
|
os->set_segment_alignment(it->second->align);
|
|
}
|
|
}
|
|
}
|
|
if (os == NULL)
|
|
return NULL;
|
|
}
|
|
|
|
// By default the GNU linker sorts input sections whose names match
|
|
// .ctors.*, .dtors.*, .init_array.*, or .fini_array.*. The
|
|
// sections are sorted by name. This is used to implement
|
|
// constructor priority ordering. We are compatible. When we put
|
|
// .ctor sections in .init_array and .dtor sections in .fini_array,
|
|
// we must also sort plain .ctor and .dtor sections.
|
|
if (!this->script_options_->saw_sections_clause()
|
|
&& !parameters->options().relocatable()
|
|
&& (is_prefix_of(".ctors.", name)
|
|
|| is_prefix_of(".dtors.", name)
|
|
|| is_prefix_of(".init_array.", name)
|
|
|| is_prefix_of(".fini_array.", name)
|
|
|| (parameters->options().ctors_in_init_array()
|
|
&& (strcmp(name, ".ctors") == 0
|
|
|| strcmp(name, ".dtors") == 0))))
|
|
os->set_must_sort_attached_input_sections();
|
|
|
|
// By default the GNU linker sorts some special text sections ahead
|
|
// of others. We are compatible.
|
|
if (parameters->options().text_reorder()
|
|
&& !this->script_options_->saw_sections_clause()
|
|
&& !this->is_section_ordering_specified()
|
|
&& !parameters->options().relocatable()
|
|
&& Layout::special_ordering_of_input_section(name) >= 0)
|
|
os->set_must_sort_attached_input_sections();
|
|
|
|
// If this is a .ctors or .ctors.* section being mapped to a
|
|
// .init_array section, or a .dtors or .dtors.* section being mapped
|
|
// to a .fini_array section, we will need to reverse the words if
|
|
// there is more than one. Record this section for later. See
|
|
// ctors_sections_in_init_array above.
|
|
if (!this->script_options_->saw_sections_clause()
|
|
&& !parameters->options().relocatable()
|
|
&& shdr.get_sh_size() > size / 8
|
|
&& (((strcmp(name, ".ctors") == 0
|
|
|| is_prefix_of(".ctors.", name))
|
|
&& strcmp(os->name(), ".init_array") == 0)
|
|
|| ((strcmp(name, ".dtors") == 0
|
|
|| is_prefix_of(".dtors.", name))
|
|
&& strcmp(os->name(), ".fini_array") == 0)))
|
|
ctors_sections_in_init_array.insert(Section_id(object, shndx));
|
|
|
|
// FIXME: Handle SHF_LINK_ORDER somewhere.
|
|
|
|
elfcpp::Elf_Xword orig_flags = os->flags();
|
|
|
|
*off = os->add_input_section(this, object, shndx, name, shdr, reloc_shndx,
|
|
this->script_options_->saw_sections_clause());
|
|
|
|
// If the flags changed, we may have to change the order.
|
|
if ((orig_flags & elfcpp::SHF_ALLOC) != 0)
|
|
{
|
|
orig_flags &= (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR);
|
|
elfcpp::Elf_Xword new_flags =
|
|
os->flags() & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR);
|
|
if (orig_flags != new_flags)
|
|
os->set_order(this->default_section_order(os, false));
|
|
}
|
|
|
|
this->have_added_input_section_ = true;
|
|
|
|
return os;
|
|
}
|
|
|
|
// Maps section SECN to SEGMENT s.
|
|
void
|
|
Layout::insert_section_segment_map(Const_section_id secn,
|
|
Unique_segment_info *s)
|
|
{
|
|
gold_assert(this->unique_segment_for_sections_specified_);
|
|
this->section_segment_map_[secn] = s;
|
|
}
|
|
|
|
// Handle a relocation section when doing a relocatable link.
|
|
|
|
template<int size, bool big_endian>
|
|
Output_section*
|
|
Layout::layout_reloc(Sized_relobj_file<size, big_endian>*,
|
|
unsigned int,
|
|
const elfcpp::Shdr<size, big_endian>& shdr,
|
|
Output_section* data_section,
|
|
Relocatable_relocs* rr)
|
|
{
|
|
gold_assert(parameters->options().relocatable()
|
|
|| parameters->options().emit_relocs());
|
|
|
|
int sh_type = shdr.get_sh_type();
|
|
|
|
std::string name;
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
name = ".rel";
|
|
else if (sh_type == elfcpp::SHT_RELA)
|
|
name = ".rela";
|
|
else
|
|
gold_unreachable();
|
|
name += data_section->name();
|
|
|
|
// If the output data section already has a reloc section, use that;
|
|
// otherwise, make a new one.
|
|
Output_section* os = data_section->reloc_section();
|
|
if (os == NULL)
|
|
{
|
|
const char* n = this->namepool_.add(name.c_str(), true, NULL);
|
|
os = this->make_output_section(n, sh_type, shdr.get_sh_flags(),
|
|
ORDER_INVALID, false);
|
|
os->set_should_link_to_symtab();
|
|
os->set_info_section(data_section);
|
|
data_section->set_reloc_section(os);
|
|
}
|
|
|
|
Output_section_data* posd;
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
{
|
|
os->set_entsize(elfcpp::Elf_sizes<size>::rel_size);
|
|
posd = new Output_relocatable_relocs<elfcpp::SHT_REL,
|
|
size,
|
|
big_endian>(rr);
|
|
}
|
|
else if (sh_type == elfcpp::SHT_RELA)
|
|
{
|
|
os->set_entsize(elfcpp::Elf_sizes<size>::rela_size);
|
|
posd = new Output_relocatable_relocs<elfcpp::SHT_RELA,
|
|
size,
|
|
big_endian>(rr);
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
|
|
os->add_output_section_data(posd);
|
|
rr->set_output_data(posd);
|
|
|
|
return os;
|
|
}
|
|
|
|
// Handle a group section when doing a relocatable link.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Layout::layout_group(Symbol_table* symtab,
|
|
Sized_relobj_file<size, big_endian>* object,
|
|
unsigned int,
|
|
const char* group_section_name,
|
|
const char* signature,
|
|
const elfcpp::Shdr<size, big_endian>& shdr,
|
|
elfcpp::Elf_Word flags,
|
|
std::vector<unsigned int>* shndxes)
|
|
{
|
|
gold_assert(parameters->options().relocatable());
|
|
gold_assert(shdr.get_sh_type() == elfcpp::SHT_GROUP);
|
|
group_section_name = this->namepool_.add(group_section_name, true, NULL);
|
|
Output_section* os = this->make_output_section(group_section_name,
|
|
elfcpp::SHT_GROUP,
|
|
shdr.get_sh_flags(),
|
|
ORDER_INVALID, false);
|
|
|
|
// We need to find a symbol with the signature in the symbol table.
|
|
// If we don't find one now, we need to look again later.
|
|
Symbol* sym = symtab->lookup(signature, NULL);
|
|
if (sym != NULL)
|
|
os->set_info_symndx(sym);
|
|
else
|
|
{
|
|
// Reserve some space to minimize reallocations.
|
|
if (this->group_signatures_.empty())
|
|
this->group_signatures_.reserve(this->number_of_input_files_ * 16);
|
|
|
|
// We will wind up using a symbol whose name is the signature.
|
|
// So just put the signature in the symbol name pool to save it.
|
|
signature = symtab->canonicalize_name(signature);
|
|
this->group_signatures_.push_back(Group_signature(os, signature));
|
|
}
|
|
|
|
os->set_should_link_to_symtab();
|
|
os->set_entsize(4);
|
|
|
|
section_size_type entry_count =
|
|
convert_to_section_size_type(shdr.get_sh_size() / 4);
|
|
Output_section_data* posd =
|
|
new Output_data_group<size, big_endian>(object, entry_count, flags,
|
|
shndxes);
|
|
os->add_output_section_data(posd);
|
|
}
|
|
|
|
// Special GNU handling of sections name .eh_frame. They will
|
|
// normally hold exception frame data as defined by the C++ ABI
|
|
// (http://codesourcery.com/cxx-abi/).
|
|
|
|
template<int size, bool big_endian>
|
|
Output_section*
|
|
Layout::layout_eh_frame(Sized_relobj_file<size, big_endian>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
const unsigned char* symbol_names,
|
|
off_t symbol_names_size,
|
|
unsigned int shndx,
|
|
const elfcpp::Shdr<size, big_endian>& shdr,
|
|
unsigned int reloc_shndx, unsigned int reloc_type,
|
|
off_t* off)
|
|
{
|
|
const unsigned int unwind_section_type =
|
|
parameters->target().unwind_section_type();
|
|
|
|
gold_assert(shdr.get_sh_type() == elfcpp::SHT_PROGBITS
|
|
|| shdr.get_sh_type() == unwind_section_type);
|
|
gold_assert((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
|
|
|
|
Output_section* os = this->make_eh_frame_section(object);
|
|
if (os == NULL)
|
|
return NULL;
|
|
|
|
gold_assert(this->eh_frame_section_ == os);
|
|
|
|
elfcpp::Elf_Xword orig_flags = os->flags();
|
|
|
|
Eh_frame::Eh_frame_section_disposition disp =
|
|
Eh_frame::EH_UNRECOGNIZED_SECTION;
|
|
if (!parameters->incremental())
|
|
{
|
|
disp = this->eh_frame_data_->add_ehframe_input_section(object,
|
|
symbols,
|
|
symbols_size,
|
|
symbol_names,
|
|
symbol_names_size,
|
|
shndx,
|
|
reloc_shndx,
|
|
reloc_type);
|
|
}
|
|
|
|
if (disp == Eh_frame::EH_OPTIMIZABLE_SECTION)
|
|
{
|
|
os->update_flags_for_input_section(shdr.get_sh_flags());
|
|
|
|
// A writable .eh_frame section is a RELRO section.
|
|
if ((orig_flags & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR))
|
|
!= (os->flags() & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR)))
|
|
{
|
|
os->set_is_relro();
|
|
os->set_order(ORDER_RELRO);
|
|
}
|
|
|
|
*off = -1;
|
|
return os;
|
|
}
|
|
|
|
if (disp == Eh_frame::EH_END_MARKER_SECTION && !this->added_eh_frame_data_)
|
|
{
|
|
// We found the end marker section, so now we can add the set of
|
|
// optimized sections to the output section. We need to postpone
|
|
// adding this until we've found a section we can optimize so that
|
|
// the .eh_frame section in crtbeginT.o winds up at the start of
|
|
// the output section.
|
|
os->add_output_section_data(this->eh_frame_data_);
|
|
this->added_eh_frame_data_ = true;
|
|
}
|
|
|
|
// We couldn't handle this .eh_frame section for some reason.
|
|
// Add it as a normal section.
|
|
bool saw_sections_clause = this->script_options_->saw_sections_clause();
|
|
*off = os->add_input_section(this, object, shndx, ".eh_frame", shdr,
|
|
reloc_shndx, saw_sections_clause);
|
|
this->have_added_input_section_ = true;
|
|
|
|
if ((orig_flags & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR))
|
|
!= (os->flags() & (elfcpp::SHF_WRITE | elfcpp::SHF_EXECINSTR)))
|
|
os->set_order(this->default_section_order(os, false));
|
|
|
|
return os;
|
|
}
|
|
|
|
void
|
|
Layout::finalize_eh_frame_section()
|
|
{
|
|
// If we never found an end marker section, we need to add the
|
|
// optimized eh sections to the output section now.
|
|
if (!parameters->incremental()
|
|
&& this->eh_frame_section_ != NULL
|
|
&& !this->added_eh_frame_data_)
|
|
{
|
|
this->eh_frame_section_->add_output_section_data(this->eh_frame_data_);
|
|
this->added_eh_frame_data_ = true;
|
|
}
|
|
}
|
|
|
|
// Create and return the magic .eh_frame section. Create
|
|
// .eh_frame_hdr also if appropriate. OBJECT is the object with the
|
|
// input .eh_frame section; it may be NULL.
|
|
|
|
Output_section*
|
|
Layout::make_eh_frame_section(const Relobj* object)
|
|
{
|
|
const unsigned int unwind_section_type =
|
|
parameters->target().unwind_section_type();
|
|
|
|
Output_section* os = this->choose_output_section(object, ".eh_frame",
|
|
unwind_section_type,
|
|
elfcpp::SHF_ALLOC, false,
|
|
ORDER_EHFRAME, false, false,
|
|
false);
|
|
if (os == NULL)
|
|
return NULL;
|
|
|
|
if (this->eh_frame_section_ == NULL)
|
|
{
|
|
this->eh_frame_section_ = os;
|
|
this->eh_frame_data_ = new Eh_frame();
|
|
|
|
// For incremental linking, we do not optimize .eh_frame sections
|
|
// or create a .eh_frame_hdr section.
|
|
if (parameters->options().eh_frame_hdr() && !parameters->incremental())
|
|
{
|
|
Output_section* hdr_os =
|
|
this->choose_output_section(NULL, ".eh_frame_hdr",
|
|
unwind_section_type,
|
|
elfcpp::SHF_ALLOC, false,
|
|
ORDER_EHFRAME, false, false,
|
|
false);
|
|
|
|
if (hdr_os != NULL)
|
|
{
|
|
Eh_frame_hdr* hdr_posd = new Eh_frame_hdr(os,
|
|
this->eh_frame_data_);
|
|
hdr_os->add_output_section_data(hdr_posd);
|
|
|
|
hdr_os->set_after_input_sections();
|
|
|
|
if (!this->script_options_->saw_phdrs_clause())
|
|
{
|
|
Output_segment* hdr_oseg;
|
|
hdr_oseg = this->make_output_segment(elfcpp::PT_GNU_EH_FRAME,
|
|
elfcpp::PF_R);
|
|
hdr_oseg->add_output_section_to_nonload(hdr_os,
|
|
elfcpp::PF_R);
|
|
}
|
|
|
|
this->eh_frame_data_->set_eh_frame_hdr(hdr_posd);
|
|
}
|
|
}
|
|
}
|
|
|
|
return os;
|
|
}
|
|
|
|
// Add an exception frame for a PLT. This is called from target code.
|
|
|
|
void
|
|
Layout::add_eh_frame_for_plt(Output_data* plt, const unsigned char* cie_data,
|
|
size_t cie_length, const unsigned char* fde_data,
|
|
size_t fde_length)
|
|
{
|
|
if (parameters->incremental())
|
|
{
|
|
// FIXME: Maybe this could work some day....
|
|
return;
|
|
}
|
|
Output_section* os = this->make_eh_frame_section(NULL);
|
|
if (os == NULL)
|
|
return;
|
|
this->eh_frame_data_->add_ehframe_for_plt(plt, cie_data, cie_length,
|
|
fde_data, fde_length);
|
|
if (!this->added_eh_frame_data_)
|
|
{
|
|
os->add_output_section_data(this->eh_frame_data_);
|
|
this->added_eh_frame_data_ = true;
|
|
}
|
|
}
|
|
|
|
// Remove all post-map .eh_frame information for a PLT.
|
|
|
|
void
|
|
Layout::remove_eh_frame_for_plt(Output_data* plt, const unsigned char* cie_data,
|
|
size_t cie_length)
|
|
{
|
|
if (parameters->incremental())
|
|
{
|
|
// FIXME: Maybe this could work some day....
|
|
return;
|
|
}
|
|
this->eh_frame_data_->remove_ehframe_for_plt(plt, cie_data, cie_length);
|
|
}
|
|
|
|
// Scan a .debug_info or .debug_types section, and add summary
|
|
// information to the .gdb_index section.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Layout::add_to_gdb_index(bool is_type_unit,
|
|
Sized_relobj<size, big_endian>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
unsigned int shndx,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type)
|
|
{
|
|
if (this->gdb_index_data_ == NULL)
|
|
{
|
|
Output_section* os = this->choose_output_section(NULL, ".gdb_index",
|
|
elfcpp::SHT_PROGBITS, 0,
|
|
false, ORDER_INVALID,
|
|
false, false, false);
|
|
if (os == NULL)
|
|
return;
|
|
|
|
this->gdb_index_data_ = new Gdb_index(os);
|
|
os->add_output_section_data(this->gdb_index_data_);
|
|
os->set_after_input_sections();
|
|
}
|
|
|
|
this->gdb_index_data_->scan_debug_info(is_type_unit, object, symbols,
|
|
symbols_size, shndx, reloc_shndx,
|
|
reloc_type);
|
|
}
|
|
|
|
// Add POSD to an output section using NAME, TYPE, and FLAGS. Return
|
|
// the output section.
|
|
|
|
Output_section*
|
|
Layout::add_output_section_data(const char* name, elfcpp::Elf_Word type,
|
|
elfcpp::Elf_Xword flags,
|
|
Output_section_data* posd,
|
|
Output_section_order order, bool is_relro)
|
|
{
|
|
Output_section* os = this->choose_output_section(NULL, name, type, flags,
|
|
false, order, is_relro,
|
|
false, false);
|
|
if (os != NULL)
|
|
os->add_output_section_data(posd);
|
|
return os;
|
|
}
|
|
|
|
// Map section flags to segment flags.
|
|
|
|
elfcpp::Elf_Word
|
|
Layout::section_flags_to_segment(elfcpp::Elf_Xword flags)
|
|
{
|
|
elfcpp::Elf_Word ret = elfcpp::PF_R;
|
|
if ((flags & elfcpp::SHF_WRITE) != 0)
|
|
ret |= elfcpp::PF_W;
|
|
if ((flags & elfcpp::SHF_EXECINSTR) != 0)
|
|
ret |= elfcpp::PF_X;
|
|
return ret;
|
|
}
|
|
|
|
// Make a new Output_section, and attach it to segments as
|
|
// appropriate. ORDER is the order in which this section should
|
|
// appear in the output segment. IS_RELRO is true if this is a relro
|
|
// (read-only after relocations) section.
|
|
|
|
Output_section*
|
|
Layout::make_output_section(const char* name, elfcpp::Elf_Word type,
|
|
elfcpp::Elf_Xword flags,
|
|
Output_section_order order, bool is_relro)
|
|
{
|
|
Output_section* os;
|
|
if ((flags & elfcpp::SHF_ALLOC) == 0
|
|
&& strcmp(parameters->options().compress_debug_sections(), "none") != 0
|
|
&& is_compressible_debug_section(name))
|
|
os = new Output_compressed_section(¶meters->options(), name, type,
|
|
flags);
|
|
else if ((flags & elfcpp::SHF_ALLOC) == 0
|
|
&& parameters->options().strip_debug_non_line()
|
|
&& strcmp(".debug_abbrev", name) == 0)
|
|
{
|
|
os = this->debug_abbrev_ = new Output_reduced_debug_abbrev_section(
|
|
name, type, flags);
|
|
if (this->debug_info_)
|
|
this->debug_info_->set_abbreviations(this->debug_abbrev_);
|
|
}
|
|
else if ((flags & elfcpp::SHF_ALLOC) == 0
|
|
&& parameters->options().strip_debug_non_line()
|
|
&& strcmp(".debug_info", name) == 0)
|
|
{
|
|
os = this->debug_info_ = new Output_reduced_debug_info_section(
|
|
name, type, flags);
|
|
if (this->debug_abbrev_)
|
|
this->debug_info_->set_abbreviations(this->debug_abbrev_);
|
|
}
|
|
else
|
|
{
|
|
// Sometimes .init_array*, .preinit_array* and .fini_array* do
|
|
// not have correct section types. Force them here.
|
|
if (type == elfcpp::SHT_PROGBITS)
|
|
{
|
|
if (is_prefix_of(".init_array", name))
|
|
type = elfcpp::SHT_INIT_ARRAY;
|
|
else if (is_prefix_of(".preinit_array", name))
|
|
type = elfcpp::SHT_PREINIT_ARRAY;
|
|
else if (is_prefix_of(".fini_array", name))
|
|
type = elfcpp::SHT_FINI_ARRAY;
|
|
}
|
|
|
|
// FIXME: const_cast is ugly.
|
|
Target* target = const_cast<Target*>(¶meters->target());
|
|
os = target->make_output_section(name, type, flags);
|
|
}
|
|
|
|
// With -z relro, we have to recognize the special sections by name.
|
|
// There is no other way.
|
|
bool is_relro_local = false;
|
|
if (!this->script_options_->saw_sections_clause()
|
|
&& parameters->options().relro()
|
|
&& (flags & elfcpp::SHF_ALLOC) != 0
|
|
&& (flags & elfcpp::SHF_WRITE) != 0)
|
|
{
|
|
if (type == elfcpp::SHT_PROGBITS)
|
|
{
|
|
if ((flags & elfcpp::SHF_TLS) != 0)
|
|
is_relro = true;
|
|
else if (strcmp(name, ".data.rel.ro") == 0)
|
|
is_relro = true;
|
|
else if (strcmp(name, ".data.rel.ro.local") == 0)
|
|
{
|
|
is_relro = true;
|
|
is_relro_local = true;
|
|
}
|
|
else if (strcmp(name, ".ctors") == 0
|
|
|| strcmp(name, ".dtors") == 0
|
|
|| strcmp(name, ".jcr") == 0)
|
|
is_relro = true;
|
|
}
|
|
else if (type == elfcpp::SHT_INIT_ARRAY
|
|
|| type == elfcpp::SHT_FINI_ARRAY
|
|
|| type == elfcpp::SHT_PREINIT_ARRAY)
|
|
is_relro = true;
|
|
}
|
|
|
|
if (is_relro)
|
|
os->set_is_relro();
|
|
|
|
if (order == ORDER_INVALID && (flags & elfcpp::SHF_ALLOC) != 0)
|
|
order = this->default_section_order(os, is_relro_local);
|
|
|
|
os->set_order(order);
|
|
|
|
parameters->target().new_output_section(os);
|
|
|
|
this->section_list_.push_back(os);
|
|
|
|
// The GNU linker by default sorts some sections by priority, so we
|
|
// do the same. We need to know that this might happen before we
|
|
// attach any input sections.
|
|
if (!this->script_options_->saw_sections_clause()
|
|
&& !parameters->options().relocatable()
|
|
&& (strcmp(name, ".init_array") == 0
|
|
|| strcmp(name, ".fini_array") == 0
|
|
|| (!parameters->options().ctors_in_init_array()
|
|
&& (strcmp(name, ".ctors") == 0
|
|
|| strcmp(name, ".dtors") == 0))))
|
|
os->set_may_sort_attached_input_sections();
|
|
|
|
// The GNU linker by default sorts .text.{unlikely,exit,startup,hot}
|
|
// sections before other .text sections. We are compatible. We
|
|
// need to know that this might happen before we attach any input
|
|
// sections.
|
|
if (parameters->options().text_reorder()
|
|
&& !this->script_options_->saw_sections_clause()
|
|
&& !this->is_section_ordering_specified()
|
|
&& !parameters->options().relocatable()
|
|
&& strcmp(name, ".text") == 0)
|
|
os->set_may_sort_attached_input_sections();
|
|
|
|
// GNU linker sorts section by name with --sort-section=name.
|
|
if (strcmp(parameters->options().sort_section(), "name") == 0)
|
|
os->set_must_sort_attached_input_sections();
|
|
|
|
// Check for .stab*str sections, as .stab* sections need to link to
|
|
// them.
|
|
if (type == elfcpp::SHT_STRTAB
|
|
&& !this->have_stabstr_section_
|
|
&& strncmp(name, ".stab", 5) == 0
|
|
&& strcmp(name + strlen(name) - 3, "str") == 0)
|
|
this->have_stabstr_section_ = true;
|
|
|
|
// During a full incremental link, we add patch space to most
|
|
// PROGBITS and NOBITS sections. Flag those that may be
|
|
// arbitrarily padded.
|
|
if ((type == elfcpp::SHT_PROGBITS || type == elfcpp::SHT_NOBITS)
|
|
&& order != ORDER_INTERP
|
|
&& order != ORDER_INIT
|
|
&& order != ORDER_PLT
|
|
&& order != ORDER_FINI
|
|
&& order != ORDER_RELRO_LAST
|
|
&& order != ORDER_NON_RELRO_FIRST
|
|
&& strcmp(name, ".eh_frame") != 0
|
|
&& strcmp(name, ".ctors") != 0
|
|
&& strcmp(name, ".dtors") != 0
|
|
&& strcmp(name, ".jcr") != 0)
|
|
{
|
|
os->set_is_patch_space_allowed();
|
|
|
|
// Certain sections require "holes" to be filled with
|
|
// specific fill patterns. These fill patterns may have
|
|
// a minimum size, so we must prevent allocations from the
|
|
// free list that leave a hole smaller than the minimum.
|
|
if (strcmp(name, ".debug_info") == 0)
|
|
os->set_free_space_fill(new Output_fill_debug_info(false));
|
|
else if (strcmp(name, ".debug_types") == 0)
|
|
os->set_free_space_fill(new Output_fill_debug_info(true));
|
|
else if (strcmp(name, ".debug_line") == 0)
|
|
os->set_free_space_fill(new Output_fill_debug_line());
|
|
}
|
|
|
|
// If we have already attached the sections to segments, then we
|
|
// need to attach this one now. This happens for sections created
|
|
// directly by the linker.
|
|
if (this->sections_are_attached_)
|
|
this->attach_section_to_segment(¶meters->target(), os);
|
|
|
|
return os;
|
|
}
|
|
|
|
// Return the default order in which a section should be placed in an
|
|
// output segment. This function captures a lot of the ideas in
|
|
// ld/scripttempl/elf.sc in the GNU linker. Note that the order of a
|
|
// linker created section is normally set when the section is created;
|
|
// this function is used for input sections.
|
|
|
|
Output_section_order
|
|
Layout::default_section_order(Output_section* os, bool is_relro_local)
|
|
{
|
|
gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0);
|
|
bool is_write = (os->flags() & elfcpp::SHF_WRITE) != 0;
|
|
bool is_execinstr = (os->flags() & elfcpp::SHF_EXECINSTR) != 0;
|
|
bool is_bss = false;
|
|
|
|
switch (os->type())
|
|
{
|
|
default:
|
|
case elfcpp::SHT_PROGBITS:
|
|
break;
|
|
case elfcpp::SHT_NOBITS:
|
|
is_bss = true;
|
|
break;
|
|
case elfcpp::SHT_RELA:
|
|
case elfcpp::SHT_REL:
|
|
if (!is_write)
|
|
return ORDER_DYNAMIC_RELOCS;
|
|
break;
|
|
case elfcpp::SHT_HASH:
|
|
case elfcpp::SHT_DYNAMIC:
|
|
case elfcpp::SHT_SHLIB:
|
|
case elfcpp::SHT_DYNSYM:
|
|
case elfcpp::SHT_GNU_HASH:
|
|
case elfcpp::SHT_GNU_verdef:
|
|
case elfcpp::SHT_GNU_verneed:
|
|
case elfcpp::SHT_GNU_versym:
|
|
if (!is_write)
|
|
return ORDER_DYNAMIC_LINKER;
|
|
break;
|
|
case elfcpp::SHT_NOTE:
|
|
return is_write ? ORDER_RW_NOTE : ORDER_RO_NOTE;
|
|
}
|
|
|
|
if ((os->flags() & elfcpp::SHF_TLS) != 0)
|
|
return is_bss ? ORDER_TLS_BSS : ORDER_TLS_DATA;
|
|
|
|
if (!is_bss && !is_write)
|
|
{
|
|
if (is_execinstr)
|
|
{
|
|
if (strcmp(os->name(), ".init") == 0)
|
|
return ORDER_INIT;
|
|
else if (strcmp(os->name(), ".fini") == 0)
|
|
return ORDER_FINI;
|
|
else if (parameters->options().keep_text_section_prefix())
|
|
{
|
|
// -z,keep-text-section-prefix introduces additional
|
|
// output sections.
|
|
if (strcmp(os->name(), ".text.hot") == 0)
|
|
return ORDER_TEXT_HOT;
|
|
else if (strcmp(os->name(), ".text.startup") == 0)
|
|
return ORDER_TEXT_STARTUP;
|
|
else if (strcmp(os->name(), ".text.exit") == 0)
|
|
return ORDER_TEXT_EXIT;
|
|
else if (strcmp(os->name(), ".text.unlikely") == 0)
|
|
return ORDER_TEXT_UNLIKELY;
|
|
}
|
|
}
|
|
return is_execinstr ? ORDER_TEXT : ORDER_READONLY;
|
|
}
|
|
|
|
if (os->is_relro())
|
|
return is_relro_local ? ORDER_RELRO_LOCAL : ORDER_RELRO;
|
|
|
|
if (os->is_small_section())
|
|
return is_bss ? ORDER_SMALL_BSS : ORDER_SMALL_DATA;
|
|
if (os->is_large_section())
|
|
return is_bss ? ORDER_LARGE_BSS : ORDER_LARGE_DATA;
|
|
|
|
return is_bss ? ORDER_BSS : ORDER_DATA;
|
|
}
|
|
|
|
// Attach output sections to segments. This is called after we have
|
|
// seen all the input sections.
|
|
|
|
void
|
|
Layout::attach_sections_to_segments(const Target* target)
|
|
{
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
this->attach_section_to_segment(target, *p);
|
|
|
|
this->sections_are_attached_ = true;
|
|
}
|
|
|
|
// Attach an output section to a segment.
|
|
|
|
void
|
|
Layout::attach_section_to_segment(const Target* target, Output_section* os)
|
|
{
|
|
if ((os->flags() & elfcpp::SHF_ALLOC) == 0)
|
|
this->unattached_section_list_.push_back(os);
|
|
else
|
|
this->attach_allocated_section_to_segment(target, os);
|
|
}
|
|
|
|
// Attach an allocated output section to a segment.
|
|
|
|
void
|
|
Layout::attach_allocated_section_to_segment(const Target* target,
|
|
Output_section* os)
|
|
{
|
|
elfcpp::Elf_Xword flags = os->flags();
|
|
gold_assert((flags & elfcpp::SHF_ALLOC) != 0);
|
|
|
|
if (parameters->options().relocatable())
|
|
return;
|
|
|
|
// If we have a SECTIONS clause, we can't handle the attachment to
|
|
// segments until after we've seen all the sections.
|
|
if (this->script_options_->saw_sections_clause())
|
|
return;
|
|
|
|
gold_assert(!this->script_options_->saw_phdrs_clause());
|
|
|
|
// This output section goes into a PT_LOAD segment.
|
|
|
|
elfcpp::Elf_Word seg_flags = Layout::section_flags_to_segment(flags);
|
|
|
|
// If this output section's segment has extra flags that need to be set,
|
|
// coming from a linker plugin, do that.
|
|
seg_flags |= os->extra_segment_flags();
|
|
|
|
// Check for --section-start.
|
|
uint64_t addr;
|
|
bool is_address_set = parameters->options().section_start(os->name(), &addr);
|
|
|
|
// In general the only thing we really care about for PT_LOAD
|
|
// segments is whether or not they are writable or executable,
|
|
// so that is how we search for them.
|
|
// Large data sections also go into their own PT_LOAD segment.
|
|
// People who need segments sorted on some other basis will
|
|
// have to use a linker script.
|
|
|
|
Segment_list::const_iterator p;
|
|
if (!os->is_unique_segment())
|
|
{
|
|
for (p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() != elfcpp::PT_LOAD)
|
|
continue;
|
|
if ((*p)->is_unique_segment())
|
|
continue;
|
|
if (!parameters->options().omagic()
|
|
&& ((*p)->flags() & elfcpp::PF_W) != (seg_flags & elfcpp::PF_W))
|
|
continue;
|
|
if ((target->isolate_execinstr() || parameters->options().rosegment())
|
|
&& ((*p)->flags() & elfcpp::PF_X) != (seg_flags & elfcpp::PF_X))
|
|
continue;
|
|
// If -Tbss was specified, we need to separate the data and BSS
|
|
// segments.
|
|
if (parameters->options().user_set_Tbss())
|
|
{
|
|
if ((os->type() == elfcpp::SHT_NOBITS)
|
|
== (*p)->has_any_data_sections())
|
|
continue;
|
|
}
|
|
if (os->is_large_data_section() && !(*p)->is_large_data_segment())
|
|
continue;
|
|
|
|
if (is_address_set)
|
|
{
|
|
if ((*p)->are_addresses_set())
|
|
continue;
|
|
|
|
(*p)->add_initial_output_data(os);
|
|
(*p)->update_flags_for_output_section(seg_flags);
|
|
(*p)->set_addresses(addr, addr);
|
|
break;
|
|
}
|
|
|
|
(*p)->add_output_section_to_load(this, os, seg_flags);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (p == this->segment_list_.end()
|
|
|| os->is_unique_segment())
|
|
{
|
|
Output_segment* oseg = this->make_output_segment(elfcpp::PT_LOAD,
|
|
seg_flags);
|
|
if (os->is_large_data_section())
|
|
oseg->set_is_large_data_segment();
|
|
oseg->add_output_section_to_load(this, os, seg_flags);
|
|
if (is_address_set)
|
|
oseg->set_addresses(addr, addr);
|
|
// Check if segment should be marked unique. For segments marked
|
|
// unique by linker plugins, set the new alignment if specified.
|
|
if (os->is_unique_segment())
|
|
{
|
|
oseg->set_is_unique_segment();
|
|
if (os->segment_alignment() != 0)
|
|
oseg->set_minimum_p_align(os->segment_alignment());
|
|
}
|
|
}
|
|
|
|
// If we see a loadable SHT_NOTE section, we create a PT_NOTE
|
|
// segment.
|
|
if (os->type() == elfcpp::SHT_NOTE)
|
|
{
|
|
uint64_t os_align = os->addralign();
|
|
|
|
// See if we already have an equivalent PT_NOTE segment.
|
|
for (p = this->segment_list_.begin();
|
|
p != segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_NOTE
|
|
&& (*p)->align() == os_align
|
|
&& (((*p)->flags() & elfcpp::PF_W)
|
|
== (seg_flags & elfcpp::PF_W)))
|
|
{
|
|
(*p)->add_output_section_to_nonload(os, seg_flags);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (p == this->segment_list_.end())
|
|
{
|
|
Output_segment* oseg = this->make_output_segment(elfcpp::PT_NOTE,
|
|
seg_flags);
|
|
oseg->add_output_section_to_nonload(os, seg_flags);
|
|
oseg->set_align(os_align);
|
|
}
|
|
}
|
|
|
|
// If we see a loadable SHF_TLS section, we create a PT_TLS
|
|
// segment. There can only be one such segment.
|
|
if ((flags & elfcpp::SHF_TLS) != 0)
|
|
{
|
|
if (this->tls_segment_ == NULL)
|
|
this->make_output_segment(elfcpp::PT_TLS, seg_flags);
|
|
this->tls_segment_->add_output_section_to_nonload(os, seg_flags);
|
|
}
|
|
|
|
// If -z relro is in effect, and we see a relro section, we create a
|
|
// PT_GNU_RELRO segment. There can only be one such segment.
|
|
if (os->is_relro() && parameters->options().relro())
|
|
{
|
|
gold_assert(seg_flags == (elfcpp::PF_R | elfcpp::PF_W));
|
|
if (this->relro_segment_ == NULL)
|
|
this->make_output_segment(elfcpp::PT_GNU_RELRO, seg_flags);
|
|
this->relro_segment_->add_output_section_to_nonload(os, seg_flags);
|
|
}
|
|
|
|
// If we see a section named .interp, put it into a PT_INTERP
|
|
// segment. This seems broken to me, but this is what GNU ld does,
|
|
// and glibc expects it.
|
|
if (strcmp(os->name(), ".interp") == 0
|
|
&& !this->script_options_->saw_phdrs_clause())
|
|
{
|
|
if (this->interp_segment_ == NULL)
|
|
this->make_output_segment(elfcpp::PT_INTERP, seg_flags);
|
|
else
|
|
gold_warning(_("multiple '.interp' sections in input files "
|
|
"may cause confusing PT_INTERP segment"));
|
|
this->interp_segment_->add_output_section_to_nonload(os, seg_flags);
|
|
}
|
|
}
|
|
|
|
// Make an output section for a script.
|
|
|
|
Output_section*
|
|
Layout::make_output_section_for_script(
|
|
const char* name,
|
|
Script_sections::Section_type section_type)
|
|
{
|
|
name = this->namepool_.add(name, false, NULL);
|
|
elfcpp::Elf_Xword sh_flags = elfcpp::SHF_ALLOC;
|
|
if (section_type == Script_sections::ST_NOLOAD)
|
|
sh_flags = 0;
|
|
Output_section* os = this->make_output_section(name, elfcpp::SHT_PROGBITS,
|
|
sh_flags, ORDER_INVALID,
|
|
false);
|
|
os->set_found_in_sections_clause();
|
|
if (section_type == Script_sections::ST_NOLOAD)
|
|
os->set_is_noload();
|
|
return os;
|
|
}
|
|
|
|
// Return the number of segments we expect to see.
|
|
|
|
size_t
|
|
Layout::expected_segment_count() const
|
|
{
|
|
size_t ret = this->segment_list_.size();
|
|
|
|
// If we didn't see a SECTIONS clause in a linker script, we should
|
|
// already have the complete list of segments. Otherwise we ask the
|
|
// SECTIONS clause how many segments it expects, and add in the ones
|
|
// we already have (PT_GNU_STACK, PT_GNU_EH_FRAME, etc.)
|
|
|
|
if (!this->script_options_->saw_sections_clause())
|
|
return ret;
|
|
else
|
|
{
|
|
const Script_sections* ss = this->script_options_->script_sections();
|
|
return ret + ss->expected_segment_count(this);
|
|
}
|
|
}
|
|
|
|
// Handle the .note.GNU-stack section at layout time. SEEN_GNU_STACK
|
|
// is whether we saw a .note.GNU-stack section in the object file.
|
|
// GNU_STACK_FLAGS is the section flags. The flags give the
|
|
// protection required for stack memory. We record this in an
|
|
// executable as a PT_GNU_STACK segment. If an object file does not
|
|
// have a .note.GNU-stack segment, we must assume that it is an old
|
|
// object. On some targets that will force an executable stack.
|
|
|
|
void
|
|
Layout::layout_gnu_stack(bool seen_gnu_stack, uint64_t gnu_stack_flags,
|
|
const Object* obj)
|
|
{
|
|
if (!seen_gnu_stack)
|
|
{
|
|
this->input_without_gnu_stack_note_ = true;
|
|
if (parameters->options().warn_execstack()
|
|
&& parameters->target().is_default_stack_executable())
|
|
gold_warning(_("%s: missing .note.GNU-stack section"
|
|
" implies executable stack"),
|
|
obj->name().c_str());
|
|
}
|
|
else
|
|
{
|
|
this->input_with_gnu_stack_note_ = true;
|
|
if ((gnu_stack_flags & elfcpp::SHF_EXECINSTR) != 0)
|
|
{
|
|
this->input_requires_executable_stack_ = true;
|
|
if (parameters->options().warn_execstack())
|
|
gold_warning(_("%s: requires executable stack"),
|
|
obj->name().c_str());
|
|
}
|
|
}
|
|
}
|
|
|
|
// Read a value with given size and endianness.
|
|
|
|
static inline uint64_t
|
|
read_sized_value(size_t size, const unsigned char* buf, bool is_big_endian,
|
|
const Object* object)
|
|
{
|
|
uint64_t val = 0;
|
|
if (size == 4)
|
|
{
|
|
if (is_big_endian)
|
|
val = elfcpp::Swap<32, true>::readval(buf);
|
|
else
|
|
val = elfcpp::Swap<32, false>::readval(buf);
|
|
}
|
|
else if (size == 8)
|
|
{
|
|
if (is_big_endian)
|
|
val = elfcpp::Swap<64, true>::readval(buf);
|
|
else
|
|
val = elfcpp::Swap<64, false>::readval(buf);
|
|
}
|
|
else
|
|
{
|
|
gold_warning(_("%s: in .note.gnu.property section, "
|
|
"pr_datasz must be 4 or 8"),
|
|
object->name().c_str());
|
|
}
|
|
return val;
|
|
}
|
|
|
|
// Write a value with given size and endianness.
|
|
|
|
static inline void
|
|
write_sized_value(uint64_t value, size_t size, unsigned char* buf,
|
|
bool is_big_endian)
|
|
{
|
|
if (size == 4)
|
|
{
|
|
if (is_big_endian)
|
|
elfcpp::Swap<32, true>::writeval(buf, static_cast<uint32_t>(value));
|
|
else
|
|
elfcpp::Swap<32, false>::writeval(buf, static_cast<uint32_t>(value));
|
|
}
|
|
else if (size == 8)
|
|
{
|
|
if (is_big_endian)
|
|
elfcpp::Swap<64, true>::writeval(buf, value);
|
|
else
|
|
elfcpp::Swap<64, false>::writeval(buf, value);
|
|
}
|
|
else
|
|
{
|
|
// We will have already complained about this.
|
|
}
|
|
}
|
|
|
|
// Handle the .note.gnu.property section at layout time.
|
|
|
|
void
|
|
Layout::layout_gnu_property(unsigned int note_type,
|
|
unsigned int pr_type,
|
|
size_t pr_datasz,
|
|
const unsigned char* pr_data,
|
|
const Object* object)
|
|
{
|
|
// We currently support only the one note type.
|
|
gold_assert(note_type == elfcpp::NT_GNU_PROPERTY_TYPE_0);
|
|
|
|
if (pr_type >= elfcpp::GNU_PROPERTY_LOPROC
|
|
&& pr_type < elfcpp::GNU_PROPERTY_HIPROC)
|
|
{
|
|
// Target-dependent property value; call the target to record.
|
|
const int size = parameters->target().get_size();
|
|
const bool is_big_endian = parameters->target().is_big_endian();
|
|
if (size == 32)
|
|
{
|
|
if (is_big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
parameters->sized_target<32, true>()->
|
|
record_gnu_property(note_type, pr_type, pr_datasz, pr_data,
|
|
object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
parameters->sized_target<32, false>()->
|
|
record_gnu_property(note_type, pr_type, pr_datasz, pr_data,
|
|
object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
}
|
|
else if (size == 64)
|
|
{
|
|
if (is_big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
parameters->sized_target<64, true>()->
|
|
record_gnu_property(note_type, pr_type, pr_datasz, pr_data,
|
|
object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
parameters->sized_target<64, false>()->
|
|
record_gnu_property(note_type, pr_type, pr_datasz, pr_data,
|
|
object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
return;
|
|
}
|
|
|
|
Gnu_properties::iterator pprop = this->gnu_properties_.find(pr_type);
|
|
if (pprop == this->gnu_properties_.end())
|
|
{
|
|
Gnu_property prop;
|
|
prop.pr_datasz = pr_datasz;
|
|
prop.pr_data = new unsigned char[pr_datasz];
|
|
memcpy(prop.pr_data, pr_data, pr_datasz);
|
|
this->gnu_properties_[pr_type] = prop;
|
|
}
|
|
else
|
|
{
|
|
const bool is_big_endian = parameters->target().is_big_endian();
|
|
switch (pr_type)
|
|
{
|
|
case elfcpp::GNU_PROPERTY_STACK_SIZE:
|
|
// Record the maximum value seen.
|
|
{
|
|
uint64_t val1 = read_sized_value(pprop->second.pr_datasz,
|
|
pprop->second.pr_data,
|
|
is_big_endian, object);
|
|
uint64_t val2 = read_sized_value(pr_datasz, pr_data,
|
|
is_big_endian, object);
|
|
if (val2 > val1)
|
|
write_sized_value(val2, pprop->second.pr_datasz,
|
|
pprop->second.pr_data, is_big_endian);
|
|
}
|
|
break;
|
|
case elfcpp::GNU_PROPERTY_NO_COPY_ON_PROTECTED:
|
|
// No data to merge.
|
|
break;
|
|
default:
|
|
gold_warning(_("%s: unknown program property type %d "
|
|
"in .note.gnu.property section"),
|
|
object->name().c_str(), pr_type);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Merge per-object properties with program properties.
|
|
// This lets the target identify objects that are missing certain
|
|
// properties, in cases where properties must be ANDed together.
|
|
|
|
void
|
|
Layout::merge_gnu_properties(const Object* object)
|
|
{
|
|
const int size = parameters->target().get_size();
|
|
const bool is_big_endian = parameters->target().is_big_endian();
|
|
if (size == 32)
|
|
{
|
|
if (is_big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
parameters->sized_target<32, true>()->merge_gnu_properties(object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
parameters->sized_target<32, false>()->merge_gnu_properties(object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
}
|
|
else if (size == 64)
|
|
{
|
|
if (is_big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
parameters->sized_target<64, true>()->merge_gnu_properties(object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
parameters->sized_target<64, false>()->merge_gnu_properties(object);
|
|
#else
|
|
gold_unreachable();
|
|
#endif
|
|
}
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
}
|
|
|
|
// Add a target-specific property for the output .note.gnu.property section.
|
|
|
|
void
|
|
Layout::add_gnu_property(unsigned int note_type,
|
|
unsigned int pr_type,
|
|
size_t pr_datasz,
|
|
const unsigned char* pr_data)
|
|
{
|
|
gold_assert(note_type == elfcpp::NT_GNU_PROPERTY_TYPE_0);
|
|
|
|
Gnu_property prop;
|
|
prop.pr_datasz = pr_datasz;
|
|
prop.pr_data = new unsigned char[pr_datasz];
|
|
memcpy(prop.pr_data, pr_data, pr_datasz);
|
|
this->gnu_properties_[pr_type] = prop;
|
|
}
|
|
|
|
// Create automatic note sections.
|
|
|
|
void
|
|
Layout::create_notes()
|
|
{
|
|
this->create_gnu_properties_note();
|
|
this->create_gold_note();
|
|
this->create_stack_segment();
|
|
this->create_build_id();
|
|
}
|
|
|
|
// Create the dynamic sections which are needed before we read the
|
|
// relocs.
|
|
|
|
void
|
|
Layout::create_initial_dynamic_sections(Symbol_table* symtab)
|
|
{
|
|
if (parameters->doing_static_link())
|
|
return;
|
|
|
|
this->dynamic_section_ = this->choose_output_section(NULL, ".dynamic",
|
|
elfcpp::SHT_DYNAMIC,
|
|
(elfcpp::SHF_ALLOC
|
|
| elfcpp::SHF_WRITE),
|
|
false, ORDER_RELRO,
|
|
true, false, false);
|
|
|
|
// A linker script may discard .dynamic, so check for NULL.
|
|
if (this->dynamic_section_ != NULL)
|
|
{
|
|
this->dynamic_symbol_ =
|
|
symtab->define_in_output_data("_DYNAMIC", NULL,
|
|
Symbol_table::PREDEFINED,
|
|
this->dynamic_section_, 0, 0,
|
|
elfcpp::STT_OBJECT, elfcpp::STB_LOCAL,
|
|
elfcpp::STV_HIDDEN, 0, false, false);
|
|
|
|
this->dynamic_data_ = new Output_data_dynamic(&this->dynpool_);
|
|
|
|
this->dynamic_section_->add_output_section_data(this->dynamic_data_);
|
|
}
|
|
}
|
|
|
|
// For each output section whose name can be represented as C symbol,
|
|
// define __start and __stop symbols for the section. This is a GNU
|
|
// extension.
|
|
|
|
void
|
|
Layout::define_section_symbols(Symbol_table* symtab)
|
|
{
|
|
const elfcpp::STV visibility = parameters->options().start_stop_visibility_enum();
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
const char* const name = (*p)->name();
|
|
if (is_cident(name))
|
|
{
|
|
const std::string name_string(name);
|
|
const std::string start_name(cident_section_start_prefix
|
|
+ name_string);
|
|
const std::string stop_name(cident_section_stop_prefix
|
|
+ name_string);
|
|
|
|
symtab->define_in_output_data(start_name.c_str(),
|
|
NULL, // version
|
|
Symbol_table::PREDEFINED,
|
|
*p,
|
|
0, // value
|
|
0, // symsize
|
|
elfcpp::STT_NOTYPE,
|
|
elfcpp::STB_GLOBAL,
|
|
visibility,
|
|
0, // nonvis
|
|
false, // offset_is_from_end
|
|
true); // only_if_ref
|
|
|
|
symtab->define_in_output_data(stop_name.c_str(),
|
|
NULL, // version
|
|
Symbol_table::PREDEFINED,
|
|
*p,
|
|
0, // value
|
|
0, // symsize
|
|
elfcpp::STT_NOTYPE,
|
|
elfcpp::STB_GLOBAL,
|
|
visibility,
|
|
0, // nonvis
|
|
true, // offset_is_from_end
|
|
true); // only_if_ref
|
|
}
|
|
}
|
|
}
|
|
|
|
// Define symbols for group signatures.
|
|
|
|
void
|
|
Layout::define_group_signatures(Symbol_table* symtab)
|
|
{
|
|
for (Group_signatures::iterator p = this->group_signatures_.begin();
|
|
p != this->group_signatures_.end();
|
|
++p)
|
|
{
|
|
Symbol* sym = symtab->lookup(p->signature, NULL);
|
|
if (sym != NULL)
|
|
p->section->set_info_symndx(sym);
|
|
else
|
|
{
|
|
// Force the name of the group section to the group
|
|
// signature, and use the group's section symbol as the
|
|
// signature symbol.
|
|
if (strcmp(p->section->name(), p->signature) != 0)
|
|
{
|
|
const char* name = this->namepool_.add(p->signature,
|
|
true, NULL);
|
|
p->section->set_name(name);
|
|
}
|
|
p->section->set_needs_symtab_index();
|
|
p->section->set_info_section_symndx(p->section);
|
|
}
|
|
}
|
|
|
|
this->group_signatures_.clear();
|
|
}
|
|
|
|
// Find the first read-only PT_LOAD segment, creating one if
|
|
// necessary.
|
|
|
|
Output_segment*
|
|
Layout::find_first_load_seg(const Target* target)
|
|
{
|
|
Output_segment* best = NULL;
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD
|
|
&& ((*p)->flags() & elfcpp::PF_R) != 0
|
|
&& (parameters->options().omagic()
|
|
|| ((*p)->flags() & elfcpp::PF_W) == 0)
|
|
&& (!target->isolate_execinstr()
|
|
|| ((*p)->flags() & elfcpp::PF_X) == 0))
|
|
{
|
|
if (best == NULL || this->segment_precedes(*p, best))
|
|
best = *p;
|
|
}
|
|
}
|
|
if (best != NULL)
|
|
return best;
|
|
|
|
gold_assert(!this->script_options_->saw_phdrs_clause());
|
|
|
|
Output_segment* load_seg = this->make_output_segment(elfcpp::PT_LOAD,
|
|
elfcpp::PF_R);
|
|
return load_seg;
|
|
}
|
|
|
|
// Save states of all current output segments. Store saved states
|
|
// in SEGMENT_STATES.
|
|
|
|
void
|
|
Layout::save_segments(Segment_states* segment_states)
|
|
{
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
Output_segment* segment = *p;
|
|
// Shallow copy.
|
|
Output_segment* copy = new Output_segment(*segment);
|
|
(*segment_states)[segment] = copy;
|
|
}
|
|
}
|
|
|
|
// Restore states of output segments and delete any segment not found in
|
|
// SEGMENT_STATES.
|
|
|
|
void
|
|
Layout::restore_segments(const Segment_states* segment_states)
|
|
{
|
|
// Go through the segment list and remove any segment added in the
|
|
// relaxation loop.
|
|
this->tls_segment_ = NULL;
|
|
this->relro_segment_ = NULL;
|
|
Segment_list::iterator list_iter = this->segment_list_.begin();
|
|
while (list_iter != this->segment_list_.end())
|
|
{
|
|
Output_segment* segment = *list_iter;
|
|
Segment_states::const_iterator states_iter =
|
|
segment_states->find(segment);
|
|
if (states_iter != segment_states->end())
|
|
{
|
|
const Output_segment* copy = states_iter->second;
|
|
// Shallow copy to restore states.
|
|
*segment = *copy;
|
|
|
|
// Also fix up TLS and RELRO segment pointers as appropriate.
|
|
if (segment->type() == elfcpp::PT_TLS)
|
|
this->tls_segment_ = segment;
|
|
else if (segment->type() == elfcpp::PT_GNU_RELRO)
|
|
this->relro_segment_ = segment;
|
|
|
|
++list_iter;
|
|
}
|
|
else
|
|
{
|
|
list_iter = this->segment_list_.erase(list_iter);
|
|
// This is a segment created during section layout. It should be
|
|
// safe to remove it since we should have removed all pointers to it.
|
|
delete segment;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Clean up after relaxation so that sections can be laid out again.
|
|
|
|
void
|
|
Layout::clean_up_after_relaxation()
|
|
{
|
|
// Restore the segments to point state just prior to the relaxation loop.
|
|
Script_sections* script_section = this->script_options_->script_sections();
|
|
script_section->release_segments();
|
|
this->restore_segments(this->segment_states_);
|
|
|
|
// Reset section addresses and file offsets
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
(*p)->restore_states();
|
|
|
|
// If an input section changes size because of relaxation,
|
|
// we need to adjust the section offsets of all input sections.
|
|
// after such a section.
|
|
if ((*p)->section_offsets_need_adjustment())
|
|
(*p)->adjust_section_offsets();
|
|
|
|
(*p)->reset_address_and_file_offset();
|
|
}
|
|
|
|
// Reset special output object address and file offsets.
|
|
for (Data_list::iterator p = this->special_output_list_.begin();
|
|
p != this->special_output_list_.end();
|
|
++p)
|
|
(*p)->reset_address_and_file_offset();
|
|
|
|
// A linker script may have created some output section data objects.
|
|
// They are useless now.
|
|
for (Output_section_data_list::const_iterator p =
|
|
this->script_output_section_data_list_.begin();
|
|
p != this->script_output_section_data_list_.end();
|
|
++p)
|
|
delete *p;
|
|
this->script_output_section_data_list_.clear();
|
|
|
|
// Special-case fill output objects are recreated each time through
|
|
// the relaxation loop.
|
|
this->reset_relax_output();
|
|
}
|
|
|
|
void
|
|
Layout::reset_relax_output()
|
|
{
|
|
for (Data_list::const_iterator p = this->relax_output_list_.begin();
|
|
p != this->relax_output_list_.end();
|
|
++p)
|
|
delete *p;
|
|
this->relax_output_list_.clear();
|
|
}
|
|
|
|
// Prepare for relaxation.
|
|
|
|
void
|
|
Layout::prepare_for_relaxation()
|
|
{
|
|
// Create an relaxation debug check if in debugging mode.
|
|
if (is_debugging_enabled(DEBUG_RELAXATION))
|
|
this->relaxation_debug_check_ = new Relaxation_debug_check();
|
|
|
|
// Save segment states.
|
|
this->segment_states_ = new Segment_states();
|
|
this->save_segments(this->segment_states_);
|
|
|
|
for(Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
(*p)->save_states();
|
|
|
|
if (is_debugging_enabled(DEBUG_RELAXATION))
|
|
this->relaxation_debug_check_->check_output_data_for_reset_values(
|
|
this->section_list_, this->special_output_list_,
|
|
this->relax_output_list_);
|
|
|
|
// Also enable recording of output section data from scripts.
|
|
this->record_output_section_data_from_script_ = true;
|
|
}
|
|
|
|
// If the user set the address of the text segment, that may not be
|
|
// compatible with putting the segment headers and file headers into
|
|
// that segment. For isolate_execinstr() targets, it's the rodata
|
|
// segment rather than text where we might put the headers.
|
|
static inline bool
|
|
load_seg_unusable_for_headers(const Target* target)
|
|
{
|
|
const General_options& options = parameters->options();
|
|
if (target->isolate_execinstr())
|
|
return (options.user_set_Trodata_segment()
|
|
&& options.Trodata_segment() % target->abi_pagesize() != 0);
|
|
else
|
|
return (options.user_set_Ttext()
|
|
&& options.Ttext() % target->abi_pagesize() != 0);
|
|
}
|
|
|
|
// Relaxation loop body: If target has no relaxation, this runs only once
|
|
// Otherwise, the target relaxation hook is called at the end of
|
|
// each iteration. If the hook returns true, it means re-layout of
|
|
// section is required.
|
|
//
|
|
// The number of segments created by a linking script without a PHDRS
|
|
// clause may be affected by section sizes and alignments. There is
|
|
// a remote chance that relaxation causes different number of PT_LOAD
|
|
// segments are created and sections are attached to different segments.
|
|
// Therefore, we always throw away all segments created during section
|
|
// layout. In order to be able to restart the section layout, we keep
|
|
// a copy of the segment list right before the relaxation loop and use
|
|
// that to restore the segments.
|
|
//
|
|
// PASS is the current relaxation pass number.
|
|
// SYMTAB is a symbol table.
|
|
// PLOAD_SEG is the address of a pointer for the load segment.
|
|
// PHDR_SEG is a pointer to the PHDR segment.
|
|
// SEGMENT_HEADERS points to the output segment header.
|
|
// FILE_HEADER points to the output file header.
|
|
// PSHNDX is the address to store the output section index.
|
|
|
|
off_t inline
|
|
Layout::relaxation_loop_body(
|
|
int pass,
|
|
Target* target,
|
|
Symbol_table* symtab,
|
|
Output_segment** pload_seg,
|
|
Output_segment* phdr_seg,
|
|
Output_segment_headers* segment_headers,
|
|
Output_file_header* file_header,
|
|
unsigned int* pshndx)
|
|
{
|
|
// If this is not the first iteration, we need to clean up after
|
|
// relaxation so that we can lay out the sections again.
|
|
if (pass != 0)
|
|
this->clean_up_after_relaxation();
|
|
|
|
// If there is a SECTIONS clause, put all the input sections into
|
|
// the required order.
|
|
Output_segment* load_seg;
|
|
if (this->script_options_->saw_sections_clause())
|
|
load_seg = this->set_section_addresses_from_script(symtab);
|
|
else if (parameters->options().relocatable())
|
|
load_seg = NULL;
|
|
else
|
|
load_seg = this->find_first_load_seg(target);
|
|
|
|
if (parameters->options().oformat_enum()
|
|
!= General_options::OBJECT_FORMAT_ELF)
|
|
load_seg = NULL;
|
|
|
|
if (load_seg_unusable_for_headers(target))
|
|
{
|
|
load_seg = NULL;
|
|
phdr_seg = NULL;
|
|
}
|
|
|
|
gold_assert(phdr_seg == NULL
|
|
|| load_seg != NULL
|
|
|| this->script_options_->saw_sections_clause());
|
|
|
|
// If the address of the load segment we found has been set by
|
|
// --section-start rather than by a script, then adjust the VMA and
|
|
// LMA downward if possible to include the file and section headers.
|
|
uint64_t header_gap = 0;
|
|
if (load_seg != NULL
|
|
&& load_seg->are_addresses_set()
|
|
&& !this->script_options_->saw_sections_clause()
|
|
&& !parameters->options().relocatable())
|
|
{
|
|
file_header->finalize_data_size();
|
|
segment_headers->finalize_data_size();
|
|
size_t sizeof_headers = (file_header->data_size()
|
|
+ segment_headers->data_size());
|
|
const uint64_t abi_pagesize = target->abi_pagesize();
|
|
uint64_t hdr_paddr = load_seg->paddr() - sizeof_headers;
|
|
hdr_paddr &= ~(abi_pagesize - 1);
|
|
uint64_t subtract = load_seg->paddr() - hdr_paddr;
|
|
if (load_seg->paddr() < subtract || load_seg->vaddr() < subtract)
|
|
load_seg = NULL;
|
|
else
|
|
{
|
|
load_seg->set_addresses(load_seg->vaddr() - subtract,
|
|
load_seg->paddr() - subtract);
|
|
header_gap = subtract - sizeof_headers;
|
|
}
|
|
}
|
|
|
|
// Lay out the segment headers.
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
gold_assert(segment_headers != NULL);
|
|
if (header_gap != 0 && load_seg != NULL)
|
|
{
|
|
Output_data_zero_fill* z = new Output_data_zero_fill(header_gap, 1);
|
|
load_seg->add_initial_output_data(z);
|
|
}
|
|
if (load_seg != NULL)
|
|
load_seg->add_initial_output_data(segment_headers);
|
|
if (phdr_seg != NULL)
|
|
phdr_seg->add_initial_output_data(segment_headers);
|
|
}
|
|
|
|
// Lay out the file header.
|
|
if (load_seg != NULL)
|
|
load_seg->add_initial_output_data(file_header);
|
|
|
|
if (this->script_options_->saw_phdrs_clause()
|
|
&& !parameters->options().relocatable())
|
|
{
|
|
// Support use of FILEHDRS and PHDRS attachments in a PHDRS
|
|
// clause in a linker script.
|
|
Script_sections* ss = this->script_options_->script_sections();
|
|
ss->put_headers_in_phdrs(file_header, segment_headers);
|
|
}
|
|
|
|
// We set the output section indexes in set_segment_offsets and
|
|
// set_section_indexes.
|
|
*pshndx = 1;
|
|
|
|
// Set the file offsets of all the segments, and all the sections
|
|
// they contain.
|
|
off_t off;
|
|
if (!parameters->options().relocatable())
|
|
off = this->set_segment_offsets(target, load_seg, pshndx);
|
|
else
|
|
off = this->set_relocatable_section_offsets(file_header, pshndx);
|
|
|
|
// Verify that the dummy relaxation does not change anything.
|
|
if (is_debugging_enabled(DEBUG_RELAXATION))
|
|
{
|
|
if (pass == 0)
|
|
this->relaxation_debug_check_->read_sections(this->section_list_);
|
|
else
|
|
this->relaxation_debug_check_->verify_sections(this->section_list_);
|
|
}
|
|
|
|
*pload_seg = load_seg;
|
|
return off;
|
|
}
|
|
|
|
// Search the list of patterns and find the position of the given section
|
|
// name in the output section. If the section name matches a glob
|
|
// pattern and a non-glob name, then the non-glob position takes
|
|
// precedence. Return 0 if no match is found.
|
|
|
|
unsigned int
|
|
Layout::find_section_order_index(const std::string& section_name)
|
|
{
|
|
Unordered_map<std::string, unsigned int>::iterator map_it;
|
|
map_it = this->input_section_position_.find(section_name);
|
|
if (map_it != this->input_section_position_.end())
|
|
return map_it->second;
|
|
|
|
// Absolute match failed. Linear search the glob patterns.
|
|
std::vector<std::string>::iterator it;
|
|
for (it = this->input_section_glob_.begin();
|
|
it != this->input_section_glob_.end();
|
|
++it)
|
|
{
|
|
if (fnmatch((*it).c_str(), section_name.c_str(), FNM_NOESCAPE) == 0)
|
|
{
|
|
map_it = this->input_section_position_.find(*it);
|
|
gold_assert(map_it != this->input_section_position_.end());
|
|
return map_it->second;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
// Read the sequence of input sections from the file specified with
|
|
// option --section-ordering-file.
|
|
|
|
void
|
|
Layout::read_layout_from_file()
|
|
{
|
|
const char* filename = parameters->options().section_ordering_file();
|
|
std::ifstream in;
|
|
std::string line;
|
|
|
|
in.open(filename);
|
|
if (!in)
|
|
gold_fatal(_("unable to open --section-ordering-file file %s: %s"),
|
|
filename, strerror(errno));
|
|
|
|
File_read::record_file_read(filename);
|
|
|
|
std::getline(in, line); // this chops off the trailing \n, if any
|
|
unsigned int position = 1;
|
|
this->set_section_ordering_specified();
|
|
|
|
while (in)
|
|
{
|
|
if (!line.empty() && line[line.length() - 1] == '\r') // Windows
|
|
line.resize(line.length() - 1);
|
|
// Ignore comments, beginning with '#'
|
|
if (line[0] == '#')
|
|
{
|
|
std::getline(in, line);
|
|
continue;
|
|
}
|
|
this->input_section_position_[line] = position;
|
|
// Store all glob patterns in a vector.
|
|
if (is_wildcard_string(line.c_str()))
|
|
this->input_section_glob_.push_back(line);
|
|
position++;
|
|
std::getline(in, line);
|
|
}
|
|
}
|
|
|
|
// Finalize the layout. When this is called, we have created all the
|
|
// output sections and all the output segments which are based on
|
|
// input sections. We have several things to do, and we have to do
|
|
// them in the right order, so that we get the right results correctly
|
|
// and efficiently.
|
|
|
|
// 1) Finalize the list of output segments and create the segment
|
|
// table header.
|
|
|
|
// 2) Finalize the dynamic symbol table and associated sections.
|
|
|
|
// 3) Determine the final file offset of all the output segments.
|
|
|
|
// 4) Determine the final file offset of all the SHF_ALLOC output
|
|
// sections.
|
|
|
|
// 5) Create the symbol table sections and the section name table
|
|
// section.
|
|
|
|
// 6) Finalize the symbol table: set symbol values to their final
|
|
// value and make a final determination of which symbols are going
|
|
// into the output symbol table.
|
|
|
|
// 7) Create the section table header.
|
|
|
|
// 8) Determine the final file offset of all the output sections which
|
|
// are not SHF_ALLOC, including the section table header.
|
|
|
|
// 9) Finalize the ELF file header.
|
|
|
|
// This function returns the size of the output file.
|
|
|
|
off_t
|
|
Layout::finalize(const Input_objects* input_objects, Symbol_table* symtab,
|
|
Target* target, const Task* task)
|
|
{
|
|
unsigned int local_dynamic_count = 0;
|
|
unsigned int forced_local_dynamic_count = 0;
|
|
|
|
target->finalize_sections(this, input_objects, symtab);
|
|
|
|
this->count_local_symbols(task, input_objects);
|
|
|
|
this->link_stabs_sections();
|
|
|
|
Output_segment* phdr_seg = NULL;
|
|
if (!parameters->options().relocatable() && !parameters->doing_static_link())
|
|
{
|
|
// There was a dynamic object in the link. We need to create
|
|
// some information for the dynamic linker.
|
|
|
|
// Create the PT_PHDR segment which will hold the program
|
|
// headers.
|
|
if (!this->script_options_->saw_phdrs_clause())
|
|
phdr_seg = this->make_output_segment(elfcpp::PT_PHDR, elfcpp::PF_R);
|
|
|
|
// Create the dynamic symbol table, including the hash table.
|
|
Output_section* dynstr;
|
|
std::vector<Symbol*> dynamic_symbols;
|
|
Versions versions(*this->script_options()->version_script_info(),
|
|
&this->dynpool_);
|
|
this->create_dynamic_symtab(input_objects, symtab, &dynstr,
|
|
&local_dynamic_count,
|
|
&forced_local_dynamic_count,
|
|
&dynamic_symbols,
|
|
&versions);
|
|
|
|
// Create the .interp section to hold the name of the
|
|
// interpreter, and put it in a PT_INTERP segment. Don't do it
|
|
// if we saw a .interp section in an input file.
|
|
if ((!parameters->options().shared()
|
|
|| parameters->options().dynamic_linker() != NULL)
|
|
&& this->interp_segment_ == NULL)
|
|
this->create_interp(target);
|
|
|
|
// Finish the .dynamic section to hold the dynamic data, and put
|
|
// it in a PT_DYNAMIC segment.
|
|
this->finish_dynamic_section(input_objects, symtab);
|
|
|
|
// We should have added everything we need to the dynamic string
|
|
// table.
|
|
this->dynpool_.set_string_offsets();
|
|
|
|
// Create the version sections. We can't do this until the
|
|
// dynamic string table is complete.
|
|
this->create_version_sections(&versions, symtab,
|
|
(local_dynamic_count
|
|
+ forced_local_dynamic_count),
|
|
dynamic_symbols, dynstr);
|
|
|
|
// Set the size of the _DYNAMIC symbol. We can't do this until
|
|
// after we call create_version_sections.
|
|
this->set_dynamic_symbol_size(symtab);
|
|
}
|
|
|
|
// Create segment headers.
|
|
Output_segment_headers* segment_headers =
|
|
(parameters->options().relocatable()
|
|
? NULL
|
|
: new Output_segment_headers(this->segment_list_));
|
|
|
|
// Lay out the file header.
|
|
Output_file_header* file_header = new Output_file_header(target, symtab,
|
|
segment_headers);
|
|
|
|
this->special_output_list_.push_back(file_header);
|
|
if (segment_headers != NULL)
|
|
this->special_output_list_.push_back(segment_headers);
|
|
|
|
// Find approriate places for orphan output sections if we are using
|
|
// a linker script.
|
|
if (this->script_options_->saw_sections_clause())
|
|
this->place_orphan_sections_in_script();
|
|
|
|
Output_segment* load_seg;
|
|
off_t off;
|
|
unsigned int shndx;
|
|
int pass = 0;
|
|
|
|
// Take a snapshot of the section layout as needed.
|
|
if (target->may_relax())
|
|
this->prepare_for_relaxation();
|
|
|
|
// Run the relaxation loop to lay out sections.
|
|
do
|
|
{
|
|
off = this->relaxation_loop_body(pass, target, symtab, &load_seg,
|
|
phdr_seg, segment_headers, file_header,
|
|
&shndx);
|
|
pass++;
|
|
}
|
|
while (target->may_relax()
|
|
&& target->relax(pass, input_objects, symtab, this, task));
|
|
|
|
// If there is a load segment that contains the file and program headers,
|
|
// provide a symbol __ehdr_start pointing there.
|
|
// A program can use this to examine itself robustly.
|
|
Symbol *ehdr_start = symtab->lookup("__ehdr_start");
|
|
if (ehdr_start != NULL && ehdr_start->is_predefined())
|
|
{
|
|
if (load_seg != NULL)
|
|
ehdr_start->set_output_segment(load_seg, Symbol::SEGMENT_START);
|
|
else
|
|
ehdr_start->set_undefined();
|
|
}
|
|
|
|
// Set the file offsets of all the non-data sections we've seen so
|
|
// far which don't have to wait for the input sections. We need
|
|
// this in order to finalize local symbols in non-allocated
|
|
// sections.
|
|
off = this->set_section_offsets(off, BEFORE_INPUT_SECTIONS_PASS);
|
|
|
|
// Set the section indexes of all unallocated sections seen so far,
|
|
// in case any of them are somehow referenced by a symbol.
|
|
shndx = this->set_section_indexes(shndx);
|
|
|
|
// Create the symbol table sections.
|
|
this->create_symtab_sections(input_objects, symtab, shndx, &off,
|
|
local_dynamic_count);
|
|
if (!parameters->doing_static_link())
|
|
this->assign_local_dynsym_offsets(input_objects);
|
|
|
|
// Process any symbol assignments from a linker script. This must
|
|
// be called after the symbol table has been finalized.
|
|
this->script_options_->finalize_symbols(symtab, this);
|
|
|
|
// Create the incremental inputs sections.
|
|
if (this->incremental_inputs_)
|
|
{
|
|
this->incremental_inputs_->finalize();
|
|
this->create_incremental_info_sections(symtab);
|
|
}
|
|
|
|
// Create the .shstrtab section.
|
|
Output_section* shstrtab_section = this->create_shstrtab();
|
|
|
|
// Set the file offsets of the rest of the non-data sections which
|
|
// don't have to wait for the input sections.
|
|
off = this->set_section_offsets(off, BEFORE_INPUT_SECTIONS_PASS);
|
|
|
|
// Now that all sections have been created, set the section indexes
|
|
// for any sections which haven't been done yet.
|
|
shndx = this->set_section_indexes(shndx);
|
|
|
|
// Create the section table header.
|
|
this->create_shdrs(shstrtab_section, &off);
|
|
|
|
// If there are no sections which require postprocessing, we can
|
|
// handle the section names now, and avoid a resize later.
|
|
if (!this->any_postprocessing_sections_)
|
|
{
|
|
off = this->set_section_offsets(off,
|
|
POSTPROCESSING_SECTIONS_PASS);
|
|
off =
|
|
this->set_section_offsets(off,
|
|
STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS);
|
|
}
|
|
|
|
file_header->set_section_info(this->section_headers_, shstrtab_section);
|
|
|
|
// Now we know exactly where everything goes in the output file
|
|
// (except for non-allocated sections which require postprocessing).
|
|
Output_data::layout_complete();
|
|
|
|
this->output_file_size_ = off;
|
|
|
|
return off;
|
|
}
|
|
|
|
// Create a note header following the format defined in the ELF ABI.
|
|
// NAME is the name, NOTE_TYPE is the type, SECTION_NAME is the name
|
|
// of the section to create, DESCSZ is the size of the descriptor.
|
|
// ALLOCATE is true if the section should be allocated in memory.
|
|
// This returns the new note section. It sets *TRAILING_PADDING to
|
|
// the number of trailing zero bytes required.
|
|
|
|
Output_section*
|
|
Layout::create_note(const char* name, int note_type,
|
|
const char* section_name, size_t descsz,
|
|
bool allocate, size_t* trailing_padding)
|
|
{
|
|
// Authorities all agree that the values in a .note field should
|
|
// be aligned on 4-byte boundaries for 32-bit binaries. However,
|
|
// they differ on what the alignment is for 64-bit binaries.
|
|
// The GABI says unambiguously they take 8-byte alignment:
|
|
// http://sco.com/developers/gabi/latest/ch5.pheader.html#note_section
|
|
// Other documentation says alignment should always be 4 bytes:
|
|
// http://www.netbsd.org/docs/kernel/elf-notes.html#note-format
|
|
// GNU ld and GNU readelf both support the latter (at least as of
|
|
// version 2.16.91), and glibc always generates the latter for
|
|
// .note.ABI-tag (as of version 1.6), so that's the one we go with
|
|
// here.
|
|
#ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION // This is not defined by default.
|
|
const int size = parameters->target().get_size();
|
|
#else
|
|
const int size = 32;
|
|
#endif
|
|
// The NT_GNU_PROPERTY_TYPE_0 note is aligned to the pointer size.
|
|
const int addralign = ((note_type == elfcpp::NT_GNU_PROPERTY_TYPE_0
|
|
? parameters->target().get_size()
|
|
: size) / 8);
|
|
|
|
// The contents of the .note section.
|
|
size_t namesz = strlen(name) + 1;
|
|
size_t aligned_namesz = align_address(namesz, size / 8);
|
|
size_t aligned_descsz = align_address(descsz, size / 8);
|
|
|
|
size_t notehdrsz = 3 * (size / 8) + aligned_namesz;
|
|
|
|
unsigned char* buffer = new unsigned char[notehdrsz];
|
|
memset(buffer, 0, notehdrsz);
|
|
|
|
bool is_big_endian = parameters->target().is_big_endian();
|
|
|
|
if (size == 32)
|
|
{
|
|
if (!is_big_endian)
|
|
{
|
|
elfcpp::Swap<32, false>::writeval(buffer, namesz);
|
|
elfcpp::Swap<32, false>::writeval(buffer + 4, descsz);
|
|
elfcpp::Swap<32, false>::writeval(buffer + 8, note_type);
|
|
}
|
|
else
|
|
{
|
|
elfcpp::Swap<32, true>::writeval(buffer, namesz);
|
|
elfcpp::Swap<32, true>::writeval(buffer + 4, descsz);
|
|
elfcpp::Swap<32, true>::writeval(buffer + 8, note_type);
|
|
}
|
|
}
|
|
else if (size == 64)
|
|
{
|
|
if (!is_big_endian)
|
|
{
|
|
elfcpp::Swap<64, false>::writeval(buffer, namesz);
|
|
elfcpp::Swap<64, false>::writeval(buffer + 8, descsz);
|
|
elfcpp::Swap<64, false>::writeval(buffer + 16, note_type);
|
|
}
|
|
else
|
|
{
|
|
elfcpp::Swap<64, true>::writeval(buffer, namesz);
|
|
elfcpp::Swap<64, true>::writeval(buffer + 8, descsz);
|
|
elfcpp::Swap<64, true>::writeval(buffer + 16, note_type);
|
|
}
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
|
|
memcpy(buffer + 3 * (size / 8), name, namesz);
|
|
|
|
elfcpp::Elf_Xword flags = 0;
|
|
Output_section_order order = ORDER_INVALID;
|
|
if (allocate)
|
|
{
|
|
flags = elfcpp::SHF_ALLOC;
|
|
order = (note_type == elfcpp::NT_GNU_PROPERTY_TYPE_0
|
|
? ORDER_PROPERTY_NOTE : ORDER_RO_NOTE);
|
|
}
|
|
Output_section* os = this->choose_output_section(NULL, section_name,
|
|
elfcpp::SHT_NOTE,
|
|
flags, false, order, false,
|
|
false, true);
|
|
if (os == NULL)
|
|
return NULL;
|
|
|
|
Output_section_data* posd = new Output_data_const_buffer(buffer, notehdrsz,
|
|
addralign,
|
|
"** note header");
|
|
os->add_output_section_data(posd);
|
|
|
|
*trailing_padding = aligned_descsz - descsz;
|
|
|
|
return os;
|
|
}
|
|
|
|
// Create a .note.gnu.property section to record program properties
|
|
// accumulated from the input files.
|
|
|
|
void
|
|
Layout::create_gnu_properties_note()
|
|
{
|
|
parameters->target().finalize_gnu_properties(this);
|
|
|
|
if (this->gnu_properties_.empty())
|
|
return;
|
|
|
|
const unsigned int size = parameters->target().get_size();
|
|
const bool is_big_endian = parameters->target().is_big_endian();
|
|
|
|
// Compute the total size of the properties array.
|
|
size_t descsz = 0;
|
|
for (Gnu_properties::const_iterator prop = this->gnu_properties_.begin();
|
|
prop != this->gnu_properties_.end();
|
|
++prop)
|
|
{
|
|
descsz = align_address(descsz + 8 + prop->second.pr_datasz, size / 8);
|
|
}
|
|
|
|
// Create the note section.
|
|
size_t trailing_padding;
|
|
Output_section* os = this->create_note("GNU", elfcpp::NT_GNU_PROPERTY_TYPE_0,
|
|
".note.gnu.property", descsz,
|
|
true, &trailing_padding);
|
|
if (os == NULL)
|
|
return;
|
|
gold_assert(trailing_padding == 0);
|
|
|
|
// Allocate and fill the properties array.
|
|
unsigned char* desc = new unsigned char[descsz];
|
|
unsigned char* p = desc;
|
|
for (Gnu_properties::const_iterator prop = this->gnu_properties_.begin();
|
|
prop != this->gnu_properties_.end();
|
|
++prop)
|
|
{
|
|
size_t datasz = prop->second.pr_datasz;
|
|
size_t aligned_datasz = align_address(prop->second.pr_datasz, size / 8);
|
|
write_sized_value(prop->first, 4, p, is_big_endian);
|
|
write_sized_value(datasz, 4, p + 4, is_big_endian);
|
|
memcpy(p + 8, prop->second.pr_data, datasz);
|
|
if (aligned_datasz > datasz)
|
|
memset(p + 8 + datasz, 0, aligned_datasz - datasz);
|
|
p += 8 + aligned_datasz;
|
|
}
|
|
Output_section_data* posd = new Output_data_const(desc, descsz, 4);
|
|
os->add_output_section_data(posd);
|
|
}
|
|
|
|
// For an executable or shared library, create a note to record the
|
|
// version of gold used to create the binary.
|
|
|
|
void
|
|
Layout::create_gold_note()
|
|
{
|
|
if (parameters->options().relocatable()
|
|
|| parameters->incremental_update())
|
|
return;
|
|
|
|
std::string desc = std::string("gold ") + gold::get_version_string();
|
|
|
|
size_t trailing_padding;
|
|
Output_section* os = this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION,
|
|
".note.gnu.gold-version", desc.size(),
|
|
false, &trailing_padding);
|
|
if (os == NULL)
|
|
return;
|
|
|
|
Output_section_data* posd = new Output_data_const(desc, 4);
|
|
os->add_output_section_data(posd);
|
|
|
|
if (trailing_padding > 0)
|
|
{
|
|
posd = new Output_data_zero_fill(trailing_padding, 0);
|
|
os->add_output_section_data(posd);
|
|
}
|
|
}
|
|
|
|
// Record whether the stack should be executable. This can be set
|
|
// from the command line using the -z execstack or -z noexecstack
|
|
// options. Otherwise, if any input file has a .note.GNU-stack
|
|
// section with the SHF_EXECINSTR flag set, the stack should be
|
|
// executable. Otherwise, if at least one input file a
|
|
// .note.GNU-stack section, and some input file has no .note.GNU-stack
|
|
// section, we use the target default for whether the stack should be
|
|
// executable. If -z stack-size was used to set a p_memsz value for
|
|
// PT_GNU_STACK, we generate the segment regardless. Otherwise, we
|
|
// don't generate a stack note. When generating a object file, we
|
|
// create a .note.GNU-stack section with the appropriate marking.
|
|
// When generating an executable or shared library, we create a
|
|
// PT_GNU_STACK segment.
|
|
|
|
void
|
|
Layout::create_stack_segment()
|
|
{
|
|
bool is_stack_executable;
|
|
if (parameters->options().is_execstack_set())
|
|
{
|
|
is_stack_executable = parameters->options().is_stack_executable();
|
|
if (!is_stack_executable
|
|
&& this->input_requires_executable_stack_
|
|
&& parameters->options().warn_execstack())
|
|
gold_warning(_("one or more inputs require executable stack, "
|
|
"but -z noexecstack was given"));
|
|
}
|
|
else if (!this->input_with_gnu_stack_note_
|
|
&& (!parameters->options().user_set_stack_size()
|
|
|| parameters->options().relocatable()))
|
|
return;
|
|
else
|
|
{
|
|
if (this->input_requires_executable_stack_)
|
|
is_stack_executable = true;
|
|
else if (this->input_without_gnu_stack_note_)
|
|
is_stack_executable =
|
|
parameters->target().is_default_stack_executable();
|
|
else
|
|
is_stack_executable = false;
|
|
}
|
|
|
|
if (parameters->options().relocatable())
|
|
{
|
|
const char* name = this->namepool_.add(".note.GNU-stack", false, NULL);
|
|
elfcpp::Elf_Xword flags = 0;
|
|
if (is_stack_executable)
|
|
flags |= elfcpp::SHF_EXECINSTR;
|
|
this->make_output_section(name, elfcpp::SHT_PROGBITS, flags,
|
|
ORDER_INVALID, false);
|
|
}
|
|
else
|
|
{
|
|
if (this->script_options_->saw_phdrs_clause())
|
|
return;
|
|
int flags = elfcpp::PF_R | elfcpp::PF_W;
|
|
if (is_stack_executable)
|
|
flags |= elfcpp::PF_X;
|
|
Output_segment* seg =
|
|
this->make_output_segment(elfcpp::PT_GNU_STACK, flags);
|
|
seg->set_size(parameters->options().stack_size());
|
|
// BFD lets targets override this default alignment, but the only
|
|
// targets that do so are ones that Gold does not support so far.
|
|
seg->set_minimum_p_align(16);
|
|
}
|
|
}
|
|
|
|
// If --build-id was used, set up the build ID note.
|
|
|
|
void
|
|
Layout::create_build_id()
|
|
{
|
|
if (!parameters->options().user_set_build_id())
|
|
return;
|
|
|
|
const char* style = parameters->options().build_id();
|
|
if (strcmp(style, "none") == 0)
|
|
return;
|
|
|
|
// Set DESCSZ to the size of the note descriptor. When possible,
|
|
// set DESC to the note descriptor contents.
|
|
size_t descsz;
|
|
std::string desc;
|
|
if (strcmp(style, "md5") == 0)
|
|
descsz = 128 / 8;
|
|
else if ((strcmp(style, "sha1") == 0) || (strcmp(style, "tree") == 0))
|
|
descsz = 160 / 8;
|
|
else if (strcmp(style, "uuid") == 0)
|
|
{
|
|
#ifndef __MINGW32__
|
|
const size_t uuidsz = 128 / 8;
|
|
|
|
char buffer[uuidsz];
|
|
memset(buffer, 0, uuidsz);
|
|
|
|
int descriptor = open_descriptor(-1, "/dev/urandom", O_RDONLY);
|
|
if (descriptor < 0)
|
|
gold_error(_("--build-id=uuid failed: could not open /dev/urandom: %s"),
|
|
strerror(errno));
|
|
else
|
|
{
|
|
ssize_t got = ::read(descriptor, buffer, uuidsz);
|
|
release_descriptor(descriptor, true);
|
|
if (got < 0)
|
|
gold_error(_("/dev/urandom: read failed: %s"), strerror(errno));
|
|
else if (static_cast<size_t>(got) != uuidsz)
|
|
gold_error(_("/dev/urandom: expected %zu bytes, got %zd bytes"),
|
|
uuidsz, got);
|
|
}
|
|
|
|
desc.assign(buffer, uuidsz);
|
|
descsz = uuidsz;
|
|
#else // __MINGW32__
|
|
UUID uuid;
|
|
typedef RPC_STATUS (RPC_ENTRY *UuidCreateFn)(UUID *Uuid);
|
|
|
|
HMODULE rpc_library = LoadLibrary("rpcrt4.dll");
|
|
if (!rpc_library)
|
|
gold_error(_("--build-id=uuid failed: could not load rpcrt4.dll"));
|
|
else
|
|
{
|
|
UuidCreateFn uuid_create = reinterpret_cast<UuidCreateFn>(
|
|
GetProcAddress(rpc_library, "UuidCreate"));
|
|
if (!uuid_create)
|
|
gold_error(_("--build-id=uuid failed: could not find UuidCreate"));
|
|
else if (uuid_create(&uuid) != RPC_S_OK)
|
|
gold_error(_("__build_id=uuid failed: call UuidCreate() failed"));
|
|
FreeLibrary(rpc_library);
|
|
}
|
|
desc.assign(reinterpret_cast<const char *>(&uuid), sizeof(UUID));
|
|
descsz = sizeof(UUID);
|
|
#endif // __MINGW32__
|
|
}
|
|
else if (strncmp(style, "0x", 2) == 0)
|
|
{
|
|
hex_init();
|
|
const char* p = style + 2;
|
|
while (*p != '\0')
|
|
{
|
|
if (hex_p(p[0]) && hex_p(p[1]))
|
|
{
|
|
char c = (hex_value(p[0]) << 4) | hex_value(p[1]);
|
|
desc += c;
|
|
p += 2;
|
|
}
|
|
else if (*p == '-' || *p == ':')
|
|
++p;
|
|
else
|
|
gold_fatal(_("--build-id argument '%s' not a valid hex number"),
|
|
style);
|
|
}
|
|
descsz = desc.size();
|
|
}
|
|
else
|
|
gold_fatal(_("unrecognized --build-id argument '%s'"), style);
|
|
|
|
// Create the note.
|
|
size_t trailing_padding;
|
|
Output_section* os = this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID,
|
|
".note.gnu.build-id", descsz, true,
|
|
&trailing_padding);
|
|
if (os == NULL)
|
|
return;
|
|
|
|
if (!desc.empty())
|
|
{
|
|
// We know the value already, so we fill it in now.
|
|
gold_assert(desc.size() == descsz);
|
|
|
|
Output_section_data* posd = new Output_data_const(desc, 4);
|
|
os->add_output_section_data(posd);
|
|
|
|
if (trailing_padding != 0)
|
|
{
|
|
posd = new Output_data_zero_fill(trailing_padding, 0);
|
|
os->add_output_section_data(posd);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// We need to compute a checksum after we have completed the
|
|
// link.
|
|
gold_assert(trailing_padding == 0);
|
|
this->build_id_note_ = new Output_data_zero_fill(descsz, 4);
|
|
os->add_output_section_data(this->build_id_note_);
|
|
}
|
|
}
|
|
|
|
// If we have both .stabXX and .stabXXstr sections, then the sh_link
|
|
// field of the former should point to the latter. I'm not sure who
|
|
// started this, but the GNU linker does it, and some tools depend
|
|
// upon it.
|
|
|
|
void
|
|
Layout::link_stabs_sections()
|
|
{
|
|
if (!this->have_stabstr_section_)
|
|
return;
|
|
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() != elfcpp::SHT_STRTAB)
|
|
continue;
|
|
|
|
const char* name = (*p)->name();
|
|
if (strncmp(name, ".stab", 5) != 0)
|
|
continue;
|
|
|
|
size_t len = strlen(name);
|
|
if (strcmp(name + len - 3, "str") != 0)
|
|
continue;
|
|
|
|
std::string stab_name(name, len - 3);
|
|
Output_section* stab_sec;
|
|
stab_sec = this->find_output_section(stab_name.c_str());
|
|
if (stab_sec != NULL)
|
|
stab_sec->set_link_section(*p);
|
|
}
|
|
}
|
|
|
|
// Create .gnu_incremental_inputs and related sections needed
|
|
// for the next run of incremental linking to check what has changed.
|
|
|
|
void
|
|
Layout::create_incremental_info_sections(Symbol_table* symtab)
|
|
{
|
|
Incremental_inputs* incr = this->incremental_inputs_;
|
|
|
|
gold_assert(incr != NULL);
|
|
|
|
// Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
|
|
incr->create_data_sections(symtab);
|
|
|
|
// Add the .gnu_incremental_inputs section.
|
|
const char* incremental_inputs_name =
|
|
this->namepool_.add(".gnu_incremental_inputs", false, NULL);
|
|
Output_section* incremental_inputs_os =
|
|
this->make_output_section(incremental_inputs_name,
|
|
elfcpp::SHT_GNU_INCREMENTAL_INPUTS, 0,
|
|
ORDER_INVALID, false);
|
|
incremental_inputs_os->add_output_section_data(incr->inputs_section());
|
|
|
|
// Add the .gnu_incremental_symtab section.
|
|
const char* incremental_symtab_name =
|
|
this->namepool_.add(".gnu_incremental_symtab", false, NULL);
|
|
Output_section* incremental_symtab_os =
|
|
this->make_output_section(incremental_symtab_name,
|
|
elfcpp::SHT_GNU_INCREMENTAL_SYMTAB, 0,
|
|
ORDER_INVALID, false);
|
|
incremental_symtab_os->add_output_section_data(incr->symtab_section());
|
|
incremental_symtab_os->set_entsize(4);
|
|
|
|
// Add the .gnu_incremental_relocs section.
|
|
const char* incremental_relocs_name =
|
|
this->namepool_.add(".gnu_incremental_relocs", false, NULL);
|
|
Output_section* incremental_relocs_os =
|
|
this->make_output_section(incremental_relocs_name,
|
|
elfcpp::SHT_GNU_INCREMENTAL_RELOCS, 0,
|
|
ORDER_INVALID, false);
|
|
incremental_relocs_os->add_output_section_data(incr->relocs_section());
|
|
incremental_relocs_os->set_entsize(incr->relocs_entsize());
|
|
|
|
// Add the .gnu_incremental_got_plt section.
|
|
const char* incremental_got_plt_name =
|
|
this->namepool_.add(".gnu_incremental_got_plt", false, NULL);
|
|
Output_section* incremental_got_plt_os =
|
|
this->make_output_section(incremental_got_plt_name,
|
|
elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT, 0,
|
|
ORDER_INVALID, false);
|
|
incremental_got_plt_os->add_output_section_data(incr->got_plt_section());
|
|
|
|
// Add the .gnu_incremental_strtab section.
|
|
const char* incremental_strtab_name =
|
|
this->namepool_.add(".gnu_incremental_strtab", false, NULL);
|
|
Output_section* incremental_strtab_os = this->make_output_section(incremental_strtab_name,
|
|
elfcpp::SHT_STRTAB, 0,
|
|
ORDER_INVALID, false);
|
|
Output_data_strtab* strtab_data =
|
|
new Output_data_strtab(incr->get_stringpool());
|
|
incremental_strtab_os->add_output_section_data(strtab_data);
|
|
|
|
incremental_inputs_os->set_after_input_sections();
|
|
incremental_symtab_os->set_after_input_sections();
|
|
incremental_relocs_os->set_after_input_sections();
|
|
incremental_got_plt_os->set_after_input_sections();
|
|
|
|
incremental_inputs_os->set_link_section(incremental_strtab_os);
|
|
incremental_symtab_os->set_link_section(incremental_inputs_os);
|
|
incremental_relocs_os->set_link_section(incremental_inputs_os);
|
|
incremental_got_plt_os->set_link_section(incremental_inputs_os);
|
|
}
|
|
|
|
// Return whether SEG1 should be before SEG2 in the output file. This
|
|
// is based entirely on the segment type and flags. When this is
|
|
// called the segment addresses have normally not yet been set.
|
|
|
|
bool
|
|
Layout::segment_precedes(const Output_segment* seg1,
|
|
const Output_segment* seg2)
|
|
{
|
|
// In order to produce a stable ordering if we're called with the same pointer
|
|
// return false.
|
|
if (seg1 == seg2)
|
|
return false;
|
|
|
|
elfcpp::Elf_Word type1 = seg1->type();
|
|
elfcpp::Elf_Word type2 = seg2->type();
|
|
|
|
// The single PT_PHDR segment is required to precede any loadable
|
|
// segment. We simply make it always first.
|
|
if (type1 == elfcpp::PT_PHDR)
|
|
{
|
|
gold_assert(type2 != elfcpp::PT_PHDR);
|
|
return true;
|
|
}
|
|
if (type2 == elfcpp::PT_PHDR)
|
|
return false;
|
|
|
|
// The single PT_INTERP segment is required to precede any loadable
|
|
// segment. We simply make it always second.
|
|
if (type1 == elfcpp::PT_INTERP)
|
|
{
|
|
gold_assert(type2 != elfcpp::PT_INTERP);
|
|
return true;
|
|
}
|
|
if (type2 == elfcpp::PT_INTERP)
|
|
return false;
|
|
|
|
// We then put PT_LOAD segments before any other segments.
|
|
if (type1 == elfcpp::PT_LOAD && type2 != elfcpp::PT_LOAD)
|
|
return true;
|
|
if (type2 == elfcpp::PT_LOAD && type1 != elfcpp::PT_LOAD)
|
|
return false;
|
|
|
|
// We put the PT_TLS segment last except for the PT_GNU_RELRO
|
|
// segment, because that is where the dynamic linker expects to find
|
|
// it (this is just for efficiency; other positions would also work
|
|
// correctly).
|
|
if (type1 == elfcpp::PT_TLS
|
|
&& type2 != elfcpp::PT_TLS
|
|
&& type2 != elfcpp::PT_GNU_RELRO)
|
|
return false;
|
|
if (type2 == elfcpp::PT_TLS
|
|
&& type1 != elfcpp::PT_TLS
|
|
&& type1 != elfcpp::PT_GNU_RELRO)
|
|
return true;
|
|
|
|
// We put the PT_GNU_RELRO segment last, because that is where the
|
|
// dynamic linker expects to find it (as with PT_TLS, this is just
|
|
// for efficiency).
|
|
if (type1 == elfcpp::PT_GNU_RELRO && type2 != elfcpp::PT_GNU_RELRO)
|
|
return false;
|
|
if (type2 == elfcpp::PT_GNU_RELRO && type1 != elfcpp::PT_GNU_RELRO)
|
|
return true;
|
|
|
|
const elfcpp::Elf_Word flags1 = seg1->flags();
|
|
const elfcpp::Elf_Word flags2 = seg2->flags();
|
|
|
|
// The order of non-PT_LOAD segments is unimportant. We simply sort
|
|
// by the numeric segment type and flags values. There should not
|
|
// be more than one segment with the same type and flags, except
|
|
// when a linker script specifies such.
|
|
if (type1 != elfcpp::PT_LOAD)
|
|
{
|
|
if (type1 != type2)
|
|
return type1 < type2;
|
|
uint64_t align1 = seg1->align();
|
|
uint64_t align2 = seg2->align();
|
|
// Place segments with larger alignments first.
|
|
if (align1 != align2)
|
|
return align1 > align2;
|
|
gold_assert(flags1 != flags2
|
|
|| this->script_options_->saw_phdrs_clause());
|
|
return flags1 < flags2;
|
|
}
|
|
|
|
// If the addresses are set already, sort by load address.
|
|
if (seg1->are_addresses_set())
|
|
{
|
|
if (!seg2->are_addresses_set())
|
|
return true;
|
|
|
|
unsigned int section_count1 = seg1->output_section_count();
|
|
unsigned int section_count2 = seg2->output_section_count();
|
|
if (section_count1 == 0 && section_count2 > 0)
|
|
return true;
|
|
if (section_count1 > 0 && section_count2 == 0)
|
|
return false;
|
|
|
|
uint64_t paddr1 = (seg1->are_addresses_set()
|
|
? seg1->paddr()
|
|
: seg1->first_section_load_address());
|
|
uint64_t paddr2 = (seg2->are_addresses_set()
|
|
? seg2->paddr()
|
|
: seg2->first_section_load_address());
|
|
|
|
if (paddr1 != paddr2)
|
|
return paddr1 < paddr2;
|
|
}
|
|
else if (seg2->are_addresses_set())
|
|
return false;
|
|
|
|
// A segment which holds large data comes after a segment which does
|
|
// not hold large data.
|
|
if (seg1->is_large_data_segment())
|
|
{
|
|
if (!seg2->is_large_data_segment())
|
|
return false;
|
|
}
|
|
else if (seg2->is_large_data_segment())
|
|
return true;
|
|
|
|
// Otherwise, we sort PT_LOAD segments based on the flags. Readonly
|
|
// segments come before writable segments. Then writable segments
|
|
// with data come before writable segments without data. Then
|
|
// executable segments come before non-executable segments. Then
|
|
// the unlikely case of a non-readable segment comes before the
|
|
// normal case of a readable segment. If there are multiple
|
|
// segments with the same type and flags, we require that the
|
|
// address be set, and we sort by virtual address and then physical
|
|
// address.
|
|
if ((flags1 & elfcpp::PF_W) != (flags2 & elfcpp::PF_W))
|
|
return (flags1 & elfcpp::PF_W) == 0;
|
|
if ((flags1 & elfcpp::PF_W) != 0
|
|
&& seg1->has_any_data_sections() != seg2->has_any_data_sections())
|
|
return seg1->has_any_data_sections();
|
|
if ((flags1 & elfcpp::PF_X) != (flags2 & elfcpp::PF_X))
|
|
return (flags1 & elfcpp::PF_X) != 0;
|
|
if ((flags1 & elfcpp::PF_R) != (flags2 & elfcpp::PF_R))
|
|
return (flags1 & elfcpp::PF_R) == 0;
|
|
|
|
// We shouldn't get here--we shouldn't create segments which we
|
|
// can't distinguish. Unless of course we are using a weird linker
|
|
// script or overlapping --section-start options. We could also get
|
|
// here if plugins want unique segments for subsets of sections.
|
|
gold_assert(this->script_options_->saw_phdrs_clause()
|
|
|| parameters->options().any_section_start()
|
|
|| this->is_unique_segment_for_sections_specified()
|
|
|| parameters->options().text_unlikely_segment());
|
|
return false;
|
|
}
|
|
|
|
// Increase OFF so that it is congruent to ADDR modulo ABI_PAGESIZE.
|
|
|
|
static off_t
|
|
align_file_offset(off_t off, uint64_t addr, uint64_t abi_pagesize)
|
|
{
|
|
uint64_t unsigned_off = off;
|
|
uint64_t aligned_off = ((unsigned_off & ~(abi_pagesize - 1))
|
|
| (addr & (abi_pagesize - 1)));
|
|
if (aligned_off < unsigned_off)
|
|
aligned_off += abi_pagesize;
|
|
return aligned_off;
|
|
}
|
|
|
|
// On targets where the text segment contains only executable code,
|
|
// a non-executable segment is never the text segment.
|
|
|
|
static inline bool
|
|
is_text_segment(const Target* target, const Output_segment* seg)
|
|
{
|
|
elfcpp::Elf_Xword flags = seg->flags();
|
|
if ((flags & elfcpp::PF_W) != 0)
|
|
return false;
|
|
if ((flags & elfcpp::PF_X) == 0)
|
|
return !target->isolate_execinstr();
|
|
return true;
|
|
}
|
|
|
|
// Set the file offsets of all the segments, and all the sections they
|
|
// contain. They have all been created. LOAD_SEG must be laid out
|
|
// first. Return the offset of the data to follow.
|
|
|
|
off_t
|
|
Layout::set_segment_offsets(const Target* target, Output_segment* load_seg,
|
|
unsigned int* pshndx)
|
|
{
|
|
// Sort them into the final order. We use a stable sort so that we
|
|
// don't randomize the order of indistinguishable segments created
|
|
// by linker scripts.
|
|
std::stable_sort(this->segment_list_.begin(), this->segment_list_.end(),
|
|
Layout::Compare_segments(this));
|
|
|
|
// Find the PT_LOAD segments, and set their addresses and offsets
|
|
// and their section's addresses and offsets.
|
|
uint64_t start_addr;
|
|
if (parameters->options().user_set_Ttext())
|
|
start_addr = parameters->options().Ttext();
|
|
else if (parameters->options().output_is_position_independent())
|
|
start_addr = 0;
|
|
else
|
|
start_addr = target->default_text_segment_address();
|
|
|
|
uint64_t addr = start_addr;
|
|
off_t off = 0;
|
|
|
|
// If LOAD_SEG is NULL, then the file header and segment headers
|
|
// will not be loadable. But they still need to be at offset 0 in
|
|
// the file. Set their offsets now.
|
|
if (load_seg == NULL)
|
|
{
|
|
for (Data_list::iterator p = this->special_output_list_.begin();
|
|
p != this->special_output_list_.end();
|
|
++p)
|
|
{
|
|
off = align_address(off, (*p)->addralign());
|
|
(*p)->set_address_and_file_offset(0, off);
|
|
off += (*p)->data_size();
|
|
}
|
|
}
|
|
|
|
unsigned int increase_relro = this->increase_relro_;
|
|
if (this->script_options_->saw_sections_clause())
|
|
increase_relro = 0;
|
|
|
|
const bool check_sections = parameters->options().check_sections();
|
|
Output_segment* last_load_segment = NULL;
|
|
|
|
unsigned int shndx_begin = *pshndx;
|
|
unsigned int shndx_load_seg = *pshndx;
|
|
|
|
for (Segment_list::iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD)
|
|
{
|
|
if (target->isolate_execinstr())
|
|
{
|
|
// When we hit the segment that should contain the
|
|
// file headers, reset the file offset so we place
|
|
// it and subsequent segments appropriately.
|
|
// We'll fix up the preceding segments below.
|
|
if (load_seg == *p)
|
|
{
|
|
if (off == 0)
|
|
load_seg = NULL;
|
|
else
|
|
{
|
|
off = 0;
|
|
shndx_load_seg = *pshndx;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// Verify that the file headers fall into the first segment.
|
|
if (load_seg != NULL && load_seg != *p)
|
|
gold_unreachable();
|
|
load_seg = NULL;
|
|
}
|
|
|
|
bool are_addresses_set = (*p)->are_addresses_set();
|
|
if (are_addresses_set)
|
|
{
|
|
// When it comes to setting file offsets, we care about
|
|
// the physical address.
|
|
addr = (*p)->paddr();
|
|
}
|
|
else if (parameters->options().user_set_Ttext()
|
|
&& (parameters->options().omagic()
|
|
|| is_text_segment(target, *p)))
|
|
{
|
|
are_addresses_set = true;
|
|
}
|
|
else if (parameters->options().user_set_Trodata_segment()
|
|
&& ((*p)->flags() & (elfcpp::PF_W | elfcpp::PF_X)) == 0)
|
|
{
|
|
addr = parameters->options().Trodata_segment();
|
|
are_addresses_set = true;
|
|
}
|
|
else if (parameters->options().user_set_Tdata()
|
|
&& ((*p)->flags() & elfcpp::PF_W) != 0
|
|
&& (!parameters->options().user_set_Tbss()
|
|
|| (*p)->has_any_data_sections()))
|
|
{
|
|
addr = parameters->options().Tdata();
|
|
are_addresses_set = true;
|
|
}
|
|
else if (parameters->options().user_set_Tbss()
|
|
&& ((*p)->flags() & elfcpp::PF_W) != 0
|
|
&& !(*p)->has_any_data_sections())
|
|
{
|
|
addr = parameters->options().Tbss();
|
|
are_addresses_set = true;
|
|
}
|
|
|
|
uint64_t orig_addr = addr;
|
|
uint64_t orig_off = off;
|
|
|
|
uint64_t aligned_addr = 0;
|
|
uint64_t abi_pagesize = target->abi_pagesize();
|
|
uint64_t common_pagesize = target->common_pagesize();
|
|
|
|
if (!parameters->options().nmagic()
|
|
&& !parameters->options().omagic())
|
|
(*p)->set_minimum_p_align(abi_pagesize);
|
|
|
|
if (!are_addresses_set)
|
|
{
|
|
// Skip the address forward one page, maintaining the same
|
|
// position within the page. This lets us store both segments
|
|
// overlapping on a single page in the file, but the loader will
|
|
// put them on different pages in memory. We will revisit this
|
|
// decision once we know the size of the segment.
|
|
|
|
uint64_t max_align = (*p)->maximum_alignment();
|
|
if (max_align > abi_pagesize)
|
|
addr = align_address(addr, max_align);
|
|
aligned_addr = addr;
|
|
|
|
if (load_seg == *p)
|
|
{
|
|
// This is the segment that will contain the file
|
|
// headers, so its offset will have to be exactly zero.
|
|
gold_assert(orig_off == 0);
|
|
|
|
// If the target wants a fixed minimum distance from the
|
|
// text segment to the read-only segment, move up now.
|
|
uint64_t min_addr =
|
|
start_addr + (parameters->options().user_set_rosegment_gap()
|
|
? parameters->options().rosegment_gap()
|
|
: target->rosegment_gap());
|
|
if (addr < min_addr)
|
|
addr = min_addr;
|
|
|
|
// But this is not the first segment! To make its
|
|
// address congruent with its offset, that address better
|
|
// be aligned to the ABI-mandated page size.
|
|
addr = align_address(addr, abi_pagesize);
|
|
aligned_addr = addr;
|
|
}
|
|
else
|
|
{
|
|
if ((addr & (abi_pagesize - 1)) != 0)
|
|
addr = addr + abi_pagesize;
|
|
|
|
off = orig_off + ((addr - orig_addr) & (abi_pagesize - 1));
|
|
}
|
|
}
|
|
|
|
if (!parameters->options().nmagic()
|
|
&& !parameters->options().omagic())
|
|
{
|
|
// Here we are also taking care of the case when
|
|
// the maximum segment alignment is larger than the page size.
|
|
off = align_file_offset(off, addr,
|
|
std::max(abi_pagesize,
|
|
(*p)->maximum_alignment()));
|
|
}
|
|
else
|
|
{
|
|
// This is -N or -n with a section script which prevents
|
|
// us from using a load segment. We need to ensure that
|
|
// the file offset is aligned to the alignment of the
|
|
// segment. This is because the linker script
|
|
// implicitly assumed a zero offset. If we don't align
|
|
// here, then the alignment of the sections in the
|
|
// linker script may not match the alignment of the
|
|
// sections in the set_section_addresses call below,
|
|
// causing an error about dot moving backward.
|
|
off = align_address(off, (*p)->maximum_alignment());
|
|
}
|
|
|
|
unsigned int shndx_hold = *pshndx;
|
|
bool has_relro = false;
|
|
uint64_t new_addr = (*p)->set_section_addresses(target, this,
|
|
false, addr,
|
|
&increase_relro,
|
|
&has_relro,
|
|
&off, pshndx);
|
|
|
|
// Now that we know the size of this segment, we may be able
|
|
// to save a page in memory, at the cost of wasting some
|
|
// file space, by instead aligning to the start of a new
|
|
// page. Here we use the real machine page size rather than
|
|
// the ABI mandated page size. If the segment has been
|
|
// aligned so that the relro data ends at a page boundary,
|
|
// we do not try to realign it.
|
|
|
|
if (!are_addresses_set
|
|
&& !has_relro
|
|
&& aligned_addr != addr
|
|
&& !parameters->incremental())
|
|
{
|
|
uint64_t first_off = (common_pagesize
|
|
- (aligned_addr
|
|
& (common_pagesize - 1)));
|
|
uint64_t last_off = new_addr & (common_pagesize - 1);
|
|
if (first_off > 0
|
|
&& last_off > 0
|
|
&& ((aligned_addr & ~ (common_pagesize - 1))
|
|
!= (new_addr & ~ (common_pagesize - 1)))
|
|
&& first_off + last_off <= common_pagesize)
|
|
{
|
|
*pshndx = shndx_hold;
|
|
addr = align_address(aligned_addr, common_pagesize);
|
|
addr = align_address(addr, (*p)->maximum_alignment());
|
|
if ((addr & (abi_pagesize - 1)) != 0)
|
|
addr = addr + abi_pagesize;
|
|
off = orig_off + ((addr - orig_addr) & (abi_pagesize - 1));
|
|
off = align_file_offset(off, addr, abi_pagesize);
|
|
|
|
increase_relro = this->increase_relro_;
|
|
if (this->script_options_->saw_sections_clause())
|
|
increase_relro = 0;
|
|
has_relro = false;
|
|
|
|
new_addr = (*p)->set_section_addresses(target, this,
|
|
true, addr,
|
|
&increase_relro,
|
|
&has_relro,
|
|
&off, pshndx);
|
|
}
|
|
}
|
|
|
|
addr = new_addr;
|
|
|
|
// Implement --check-sections. We know that the segments
|
|
// are sorted by LMA.
|
|
if (check_sections && last_load_segment != NULL)
|
|
{
|
|
gold_assert(last_load_segment->paddr() <= (*p)->paddr());
|
|
if (last_load_segment->paddr() + last_load_segment->memsz()
|
|
> (*p)->paddr())
|
|
{
|
|
unsigned long long lb1 = last_load_segment->paddr();
|
|
unsigned long long le1 = lb1 + last_load_segment->memsz();
|
|
unsigned long long lb2 = (*p)->paddr();
|
|
unsigned long long le2 = lb2 + (*p)->memsz();
|
|
gold_error(_("load segment overlap [0x%llx -> 0x%llx] and "
|
|
"[0x%llx -> 0x%llx]"),
|
|
lb1, le1, lb2, le2);
|
|
}
|
|
}
|
|
last_load_segment = *p;
|
|
}
|
|
}
|
|
|
|
if (load_seg != NULL && target->isolate_execinstr())
|
|
{
|
|
// Process the early segments again, setting their file offsets
|
|
// so they land after the segments starting at LOAD_SEG.
|
|
off = align_file_offset(off, 0, target->abi_pagesize());
|
|
|
|
this->reset_relax_output();
|
|
|
|
for (Segment_list::iterator p = this->segment_list_.begin();
|
|
*p != load_seg;
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD)
|
|
{
|
|
// We repeat the whole job of assigning addresses and
|
|
// offsets, but we really only want to change the offsets and
|
|
// must ensure that the addresses all come out the same as
|
|
// they did the first time through.
|
|
bool has_relro = false;
|
|
const uint64_t old_addr = (*p)->vaddr();
|
|
const uint64_t old_end = old_addr + (*p)->memsz();
|
|
uint64_t new_addr = (*p)->set_section_addresses(target, this,
|
|
true, old_addr,
|
|
&increase_relro,
|
|
&has_relro,
|
|
&off,
|
|
&shndx_begin);
|
|
gold_assert(new_addr == old_end);
|
|
}
|
|
}
|
|
|
|
gold_assert(shndx_begin == shndx_load_seg);
|
|
}
|
|
|
|
// Handle the non-PT_LOAD segments, setting their offsets from their
|
|
// section's offsets.
|
|
for (Segment_list::iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
// PT_GNU_STACK was set up correctly when it was created.
|
|
if ((*p)->type() != elfcpp::PT_LOAD
|
|
&& (*p)->type() != elfcpp::PT_GNU_STACK)
|
|
(*p)->set_offset((*p)->type() == elfcpp::PT_GNU_RELRO
|
|
? increase_relro
|
|
: 0);
|
|
}
|
|
|
|
// Set the TLS offsets for each section in the PT_TLS segment.
|
|
if (this->tls_segment_ != NULL)
|
|
this->tls_segment_->set_tls_offsets();
|
|
|
|
return off;
|
|
}
|
|
|
|
// Set the offsets of all the allocated sections when doing a
|
|
// relocatable link. This does the same jobs as set_segment_offsets,
|
|
// only for a relocatable link.
|
|
|
|
off_t
|
|
Layout::set_relocatable_section_offsets(Output_data* file_header,
|
|
unsigned int* pshndx)
|
|
{
|
|
off_t off = 0;
|
|
|
|
file_header->set_address_and_file_offset(0, 0);
|
|
off += file_header->data_size();
|
|
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
// We skip unallocated sections here, except that group sections
|
|
// have to come first.
|
|
if (((*p)->flags() & elfcpp::SHF_ALLOC) == 0
|
|
&& (*p)->type() != elfcpp::SHT_GROUP)
|
|
continue;
|
|
|
|
off = align_address(off, (*p)->addralign());
|
|
|
|
// The linker script might have set the address.
|
|
if (!(*p)->is_address_valid())
|
|
(*p)->set_address(0);
|
|
(*p)->set_file_offset(off);
|
|
(*p)->finalize_data_size();
|
|
if ((*p)->type() != elfcpp::SHT_NOBITS)
|
|
off += (*p)->data_size();
|
|
|
|
(*p)->set_out_shndx(*pshndx);
|
|
++*pshndx;
|
|
}
|
|
|
|
return off;
|
|
}
|
|
|
|
// Set the file offset of all the sections not associated with a
|
|
// segment.
|
|
|
|
off_t
|
|
Layout::set_section_offsets(off_t off, Layout::Section_offset_pass pass)
|
|
{
|
|
off_t startoff = off;
|
|
off_t maxoff = off;
|
|
|
|
for (Section_list::iterator p = this->unattached_section_list_.begin();
|
|
p != this->unattached_section_list_.end();
|
|
++p)
|
|
{
|
|
// The symtab section is handled in create_symtab_sections.
|
|
if (*p == this->symtab_section_)
|
|
continue;
|
|
|
|
// If we've already set the data size, don't set it again.
|
|
if ((*p)->is_offset_valid() && (*p)->is_data_size_valid())
|
|
continue;
|
|
|
|
if (pass == BEFORE_INPUT_SECTIONS_PASS
|
|
&& (*p)->requires_postprocessing())
|
|
{
|
|
(*p)->create_postprocessing_buffer();
|
|
this->any_postprocessing_sections_ = true;
|
|
}
|
|
|
|
if (pass == BEFORE_INPUT_SECTIONS_PASS
|
|
&& (*p)->after_input_sections())
|
|
continue;
|
|
else if (pass == POSTPROCESSING_SECTIONS_PASS
|
|
&& (!(*p)->after_input_sections()
|
|
|| (*p)->type() == elfcpp::SHT_STRTAB))
|
|
continue;
|
|
else if (pass == STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
|
|
&& (!(*p)->after_input_sections()
|
|
|| (*p)->type() != elfcpp::SHT_STRTAB))
|
|
continue;
|
|
|
|
if (!parameters->incremental_update())
|
|
{
|
|
off = align_address(off, (*p)->addralign());
|
|
(*p)->set_file_offset(off);
|
|
(*p)->finalize_data_size();
|
|
}
|
|
else
|
|
{
|
|
// Incremental update: allocate file space from free list.
|
|
(*p)->pre_finalize_data_size();
|
|
off_t current_size = (*p)->current_data_size();
|
|
off = this->allocate(current_size, (*p)->addralign(), startoff);
|
|
if (off == -1)
|
|
{
|
|
if (is_debugging_enabled(DEBUG_INCREMENTAL))
|
|
this->free_list_.dump();
|
|
gold_assert((*p)->output_section() != NULL);
|
|
gold_fallback(_("out of patch space for section %s; "
|
|
"relink with --incremental-full"),
|
|
(*p)->output_section()->name());
|
|
}
|
|
(*p)->set_file_offset(off);
|
|
(*p)->finalize_data_size();
|
|
if ((*p)->data_size() > current_size)
|
|
{
|
|
gold_assert((*p)->output_section() != NULL);
|
|
gold_fallback(_("%s: section changed size; "
|
|
"relink with --incremental-full"),
|
|
(*p)->output_section()->name());
|
|
}
|
|
gold_debug(DEBUG_INCREMENTAL,
|
|
"set_section_offsets: %08lx %08lx %s",
|
|
static_cast<long>(off),
|
|
static_cast<long>((*p)->data_size()),
|
|
((*p)->output_section() != NULL
|
|
? (*p)->output_section()->name() : "(special)"));
|
|
}
|
|
|
|
off += (*p)->data_size();
|
|
if (off > maxoff)
|
|
maxoff = off;
|
|
|
|
// At this point the name must be set.
|
|
if (pass != STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS)
|
|
this->namepool_.add((*p)->name(), false, NULL);
|
|
}
|
|
return maxoff;
|
|
}
|
|
|
|
// Set the section indexes of all the sections not associated with a
|
|
// segment.
|
|
|
|
unsigned int
|
|
Layout::set_section_indexes(unsigned int shndx)
|
|
{
|
|
for (Section_list::iterator p = this->unattached_section_list_.begin();
|
|
p != this->unattached_section_list_.end();
|
|
++p)
|
|
{
|
|
if (!(*p)->has_out_shndx())
|
|
{
|
|
(*p)->set_out_shndx(shndx);
|
|
++shndx;
|
|
}
|
|
}
|
|
return shndx;
|
|
}
|
|
|
|
// Set the section addresses according to the linker script. This is
|
|
// only called when we see a SECTIONS clause. This returns the
|
|
// program segment which should hold the file header and segment
|
|
// headers, if any. It will return NULL if they should not be in a
|
|
// segment.
|
|
|
|
Output_segment*
|
|
Layout::set_section_addresses_from_script(Symbol_table* symtab)
|
|
{
|
|
Script_sections* ss = this->script_options_->script_sections();
|
|
gold_assert(ss->saw_sections_clause());
|
|
return this->script_options_->set_section_addresses(symtab, this);
|
|
}
|
|
|
|
// Place the orphan sections in the linker script.
|
|
|
|
void
|
|
Layout::place_orphan_sections_in_script()
|
|
{
|
|
Script_sections* ss = this->script_options_->script_sections();
|
|
gold_assert(ss->saw_sections_clause());
|
|
|
|
// Place each orphaned output section in the script.
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if (!(*p)->found_in_sections_clause())
|
|
ss->place_orphan(*p);
|
|
}
|
|
}
|
|
|
|
// Count the local symbols in the regular symbol table and the dynamic
|
|
// symbol table, and build the respective string pools.
|
|
|
|
void
|
|
Layout::count_local_symbols(const Task* task,
|
|
const Input_objects* input_objects)
|
|
{
|
|
// First, figure out an upper bound on the number of symbols we'll
|
|
// be inserting into each pool. This helps us create the pools with
|
|
// the right size, to avoid unnecessary hashtable resizing.
|
|
unsigned int symbol_count = 0;
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
symbol_count += (*p)->local_symbol_count();
|
|
|
|
// Go from "upper bound" to "estimate." We overcount for two
|
|
// reasons: we double-count symbols that occur in more than one
|
|
// object file, and we count symbols that are dropped from the
|
|
// output. Add it all together and assume we overcount by 100%.
|
|
symbol_count /= 2;
|
|
|
|
// We assume all symbols will go into both the sympool and dynpool.
|
|
this->sympool_.reserve(symbol_count);
|
|
this->dynpool_.reserve(symbol_count);
|
|
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
Task_lock_obj<Object> tlo(task, *p);
|
|
(*p)->count_local_symbols(&this->sympool_, &this->dynpool_);
|
|
}
|
|
}
|
|
|
|
// Create the symbol table sections. Here we also set the final
|
|
// values of the symbols. At this point all the loadable sections are
|
|
// fully laid out. SHNUM is the number of sections so far.
|
|
|
|
void
|
|
Layout::create_symtab_sections(const Input_objects* input_objects,
|
|
Symbol_table* symtab,
|
|
unsigned int shnum,
|
|
off_t* poff,
|
|
unsigned int local_dynamic_count)
|
|
{
|
|
int symsize;
|
|
unsigned int align;
|
|
if (parameters->target().get_size() == 32)
|
|
{
|
|
symsize = elfcpp::Elf_sizes<32>::sym_size;
|
|
align = 4;
|
|
}
|
|
else if (parameters->target().get_size() == 64)
|
|
{
|
|
symsize = elfcpp::Elf_sizes<64>::sym_size;
|
|
align = 8;
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
|
|
// Compute file offsets relative to the start of the symtab section.
|
|
off_t off = 0;
|
|
|
|
// Save space for the dummy symbol at the start of the section. We
|
|
// never bother to write this out--it will just be left as zero.
|
|
off += symsize;
|
|
unsigned int local_symbol_index = 1;
|
|
|
|
// Add STT_SECTION symbols for each Output section which needs one.
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if (!(*p)->needs_symtab_index())
|
|
(*p)->set_symtab_index(-1U);
|
|
else
|
|
{
|
|
(*p)->set_symtab_index(local_symbol_index);
|
|
++local_symbol_index;
|
|
off += symsize;
|
|
}
|
|
}
|
|
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
unsigned int index = (*p)->finalize_local_symbols(local_symbol_index,
|
|
off, symtab);
|
|
off += (index - local_symbol_index) * symsize;
|
|
local_symbol_index = index;
|
|
}
|
|
|
|
unsigned int local_symcount = local_symbol_index;
|
|
gold_assert(static_cast<off_t>(local_symcount * symsize) == off);
|
|
|
|
off_t dynoff;
|
|
size_t dyncount;
|
|
if (this->dynsym_section_ == NULL)
|
|
{
|
|
dynoff = 0;
|
|
dyncount = 0;
|
|
}
|
|
else
|
|
{
|
|
off_t locsize = local_dynamic_count * this->dynsym_section_->entsize();
|
|
dynoff = this->dynsym_section_->offset() + locsize;
|
|
dyncount = (this->dynsym_section_->data_size() - locsize) / symsize;
|
|
gold_assert(static_cast<off_t>(dyncount * symsize)
|
|
== this->dynsym_section_->data_size() - locsize);
|
|
}
|
|
|
|
off_t global_off = off;
|
|
off = symtab->finalize(off, dynoff, local_dynamic_count, dyncount,
|
|
&this->sympool_, &local_symcount);
|
|
|
|
if (!parameters->options().strip_all())
|
|
{
|
|
this->sympool_.set_string_offsets();
|
|
|
|
const char* symtab_name = this->namepool_.add(".symtab", false, NULL);
|
|
Output_section* osymtab = this->make_output_section(symtab_name,
|
|
elfcpp::SHT_SYMTAB,
|
|
0, ORDER_INVALID,
|
|
false);
|
|
this->symtab_section_ = osymtab;
|
|
|
|
Output_section_data* pos = new Output_data_fixed_space(off, align,
|
|
"** symtab");
|
|
osymtab->add_output_section_data(pos);
|
|
|
|
// We generate a .symtab_shndx section if we have more than
|
|
// SHN_LORESERVE sections. Technically it is possible that we
|
|
// don't need one, because it is possible that there are no
|
|
// symbols in any of sections with indexes larger than
|
|
// SHN_LORESERVE. That is probably unusual, though, and it is
|
|
// easier to always create one than to compute section indexes
|
|
// twice (once here, once when writing out the symbols).
|
|
if (shnum >= elfcpp::SHN_LORESERVE)
|
|
{
|
|
const char* symtab_xindex_name = this->namepool_.add(".symtab_shndx",
|
|
false, NULL);
|
|
Output_section* osymtab_xindex =
|
|
this->make_output_section(symtab_xindex_name,
|
|
elfcpp::SHT_SYMTAB_SHNDX, 0,
|
|
ORDER_INVALID, false);
|
|
|
|
size_t symcount = off / symsize;
|
|
this->symtab_xindex_ = new Output_symtab_xindex(symcount);
|
|
|
|
osymtab_xindex->add_output_section_data(this->symtab_xindex_);
|
|
|
|
osymtab_xindex->set_link_section(osymtab);
|
|
osymtab_xindex->set_addralign(4);
|
|
osymtab_xindex->set_entsize(4);
|
|
|
|
osymtab_xindex->set_after_input_sections();
|
|
|
|
// This tells the driver code to wait until the symbol table
|
|
// has written out before writing out the postprocessing
|
|
// sections, including the .symtab_shndx section.
|
|
this->any_postprocessing_sections_ = true;
|
|
}
|
|
|
|
const char* strtab_name = this->namepool_.add(".strtab", false, NULL);
|
|
Output_section* ostrtab = this->make_output_section(strtab_name,
|
|
elfcpp::SHT_STRTAB,
|
|
0, ORDER_INVALID,
|
|
false);
|
|
|
|
Output_section_data* pstr = new Output_data_strtab(&this->sympool_);
|
|
ostrtab->add_output_section_data(pstr);
|
|
|
|
off_t symtab_off;
|
|
if (!parameters->incremental_update())
|
|
symtab_off = align_address(*poff, align);
|
|
else
|
|
{
|
|
symtab_off = this->allocate(off, align, *poff);
|
|
if (off == -1)
|
|
gold_fallback(_("out of patch space for symbol table; "
|
|
"relink with --incremental-full"));
|
|
gold_debug(DEBUG_INCREMENTAL,
|
|
"create_symtab_sections: %08lx %08lx .symtab",
|
|
static_cast<long>(symtab_off),
|
|
static_cast<long>(off));
|
|
}
|
|
|
|
symtab->set_file_offset(symtab_off + global_off);
|
|
osymtab->set_file_offset(symtab_off);
|
|
osymtab->finalize_data_size();
|
|
osymtab->set_link_section(ostrtab);
|
|
osymtab->set_info(local_symcount);
|
|
osymtab->set_entsize(symsize);
|
|
|
|
if (symtab_off + off > *poff)
|
|
*poff = symtab_off + off;
|
|
}
|
|
}
|
|
|
|
// Create the .shstrtab section, which holds the names of the
|
|
// sections. At the time this is called, we have created all the
|
|
// output sections except .shstrtab itself.
|
|
|
|
Output_section*
|
|
Layout::create_shstrtab()
|
|
{
|
|
// FIXME: We don't need to create a .shstrtab section if we are
|
|
// stripping everything.
|
|
|
|
const char* name = this->namepool_.add(".shstrtab", false, NULL);
|
|
|
|
Output_section* os = this->make_output_section(name, elfcpp::SHT_STRTAB, 0,
|
|
ORDER_INVALID, false);
|
|
|
|
if (strcmp(parameters->options().compress_debug_sections(), "none") != 0)
|
|
{
|
|
// We can't write out this section until we've set all the
|
|
// section names, and we don't set the names of compressed
|
|
// output sections until relocations are complete. FIXME: With
|
|
// the current names we use, this is unnecessary.
|
|
os->set_after_input_sections();
|
|
}
|
|
|
|
Output_section_data* posd = new Output_data_strtab(&this->namepool_);
|
|
os->add_output_section_data(posd);
|
|
|
|
return os;
|
|
}
|
|
|
|
// Create the section headers. SIZE is 32 or 64. OFF is the file
|
|
// offset.
|
|
|
|
void
|
|
Layout::create_shdrs(const Output_section* shstrtab_section, off_t* poff)
|
|
{
|
|
Output_section_headers* oshdrs;
|
|
oshdrs = new Output_section_headers(this,
|
|
&this->segment_list_,
|
|
&this->section_list_,
|
|
&this->unattached_section_list_,
|
|
&this->namepool_,
|
|
shstrtab_section);
|
|
off_t off;
|
|
if (!parameters->incremental_update())
|
|
off = align_address(*poff, oshdrs->addralign());
|
|
else
|
|
{
|
|
oshdrs->pre_finalize_data_size();
|
|
off = this->allocate(oshdrs->data_size(), oshdrs->addralign(), *poff);
|
|
if (off == -1)
|
|
gold_fallback(_("out of patch space for section header table; "
|
|
"relink with --incremental-full"));
|
|
gold_debug(DEBUG_INCREMENTAL,
|
|
"create_shdrs: %08lx %08lx (section header table)",
|
|
static_cast<long>(off),
|
|
static_cast<long>(off + oshdrs->data_size()));
|
|
}
|
|
oshdrs->set_address_and_file_offset(0, off);
|
|
off += oshdrs->data_size();
|
|
if (off > *poff)
|
|
*poff = off;
|
|
this->section_headers_ = oshdrs;
|
|
}
|
|
|
|
// Count the allocated sections.
|
|
|
|
size_t
|
|
Layout::allocated_output_section_count() const
|
|
{
|
|
size_t section_count = 0;
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
section_count += (*p)->output_section_count();
|
|
return section_count;
|
|
}
|
|
|
|
// Create the dynamic symbol table.
|
|
// *PLOCAL_DYNAMIC_COUNT will be set to the number of local symbols
|
|
// from input objects, and *PFORCED_LOCAL_DYNAMIC_COUNT will be set
|
|
// to the number of global symbols that have been forced local.
|
|
// We need to remember the former because the forced-local symbols are
|
|
// written along with the global symbols in Symtab::write_globals().
|
|
|
|
void
|
|
Layout::create_dynamic_symtab(const Input_objects* input_objects,
|
|
Symbol_table* symtab,
|
|
Output_section** pdynstr,
|
|
unsigned int* plocal_dynamic_count,
|
|
unsigned int* pforced_local_dynamic_count,
|
|
std::vector<Symbol*>* pdynamic_symbols,
|
|
Versions* pversions)
|
|
{
|
|
// Count all the symbols in the dynamic symbol table, and set the
|
|
// dynamic symbol indexes.
|
|
|
|
// Skip symbol 0, which is always all zeroes.
|
|
unsigned int index = 1;
|
|
|
|
// Add STT_SECTION symbols for each Output section which needs one.
|
|
for (Section_list::iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if (!(*p)->needs_dynsym_index())
|
|
(*p)->set_dynsym_index(-1U);
|
|
else
|
|
{
|
|
(*p)->set_dynsym_index(index);
|
|
++index;
|
|
}
|
|
}
|
|
|
|
// Count the local symbols that need to go in the dynamic symbol table,
|
|
// and set the dynamic symbol indexes.
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
unsigned int new_index = (*p)->set_local_dynsym_indexes(index);
|
|
index = new_index;
|
|
}
|
|
|
|
unsigned int local_symcount = index;
|
|
unsigned int forced_local_count = 0;
|
|
|
|
index = symtab->set_dynsym_indexes(index, &forced_local_count,
|
|
pdynamic_symbols, &this->dynpool_,
|
|
pversions);
|
|
|
|
*plocal_dynamic_count = local_symcount;
|
|
*pforced_local_dynamic_count = forced_local_count;
|
|
|
|
int symsize;
|
|
unsigned int align;
|
|
const int size = parameters->target().get_size();
|
|
if (size == 32)
|
|
{
|
|
symsize = elfcpp::Elf_sizes<32>::sym_size;
|
|
align = 4;
|
|
}
|
|
else if (size == 64)
|
|
{
|
|
symsize = elfcpp::Elf_sizes<64>::sym_size;
|
|
align = 8;
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
|
|
// Create the dynamic symbol table section.
|
|
|
|
Output_section* dynsym = this->choose_output_section(NULL, ".dynsym",
|
|
elfcpp::SHT_DYNSYM,
|
|
elfcpp::SHF_ALLOC,
|
|
false,
|
|
ORDER_DYNAMIC_LINKER,
|
|
false, false, false);
|
|
|
|
// Check for NULL as a linker script may discard .dynsym.
|
|
if (dynsym != NULL)
|
|
{
|
|
Output_section_data* odata = new Output_data_fixed_space(index * symsize,
|
|
align,
|
|
"** dynsym");
|
|
dynsym->add_output_section_data(odata);
|
|
|
|
dynsym->set_info(local_symcount + forced_local_count);
|
|
dynsym->set_entsize(symsize);
|
|
dynsym->set_addralign(align);
|
|
|
|
this->dynsym_section_ = dynsym;
|
|
}
|
|
|
|
Output_data_dynamic* const odyn = this->dynamic_data_;
|
|
if (odyn != NULL)
|
|
{
|
|
odyn->add_section_address(elfcpp::DT_SYMTAB, dynsym);
|
|
odyn->add_constant(elfcpp::DT_SYMENT, symsize);
|
|
}
|
|
|
|
// If there are more than SHN_LORESERVE allocated sections, we
|
|
// create a .dynsym_shndx section. It is possible that we don't
|
|
// need one, because it is possible that there are no dynamic
|
|
// symbols in any of the sections with indexes larger than
|
|
// SHN_LORESERVE. This is probably unusual, though, and at this
|
|
// time we don't know the actual section indexes so it is
|
|
// inconvenient to check.
|
|
if (this->allocated_output_section_count() >= elfcpp::SHN_LORESERVE)
|
|
{
|
|
Output_section* dynsym_xindex =
|
|
this->choose_output_section(NULL, ".dynsym_shndx",
|
|
elfcpp::SHT_SYMTAB_SHNDX,
|
|
elfcpp::SHF_ALLOC,
|
|
false, ORDER_DYNAMIC_LINKER, false, false,
|
|
false);
|
|
|
|
if (dynsym_xindex != NULL)
|
|
{
|
|
this->dynsym_xindex_ = new Output_symtab_xindex(index);
|
|
|
|
dynsym_xindex->add_output_section_data(this->dynsym_xindex_);
|
|
|
|
dynsym_xindex->set_link_section(dynsym);
|
|
dynsym_xindex->set_addralign(4);
|
|
dynsym_xindex->set_entsize(4);
|
|
|
|
dynsym_xindex->set_after_input_sections();
|
|
|
|
// This tells the driver code to wait until the symbol table
|
|
// has written out before writing out the postprocessing
|
|
// sections, including the .dynsym_shndx section.
|
|
this->any_postprocessing_sections_ = true;
|
|
}
|
|
}
|
|
|
|
// Create the dynamic string table section.
|
|
|
|
Output_section* dynstr = this->choose_output_section(NULL, ".dynstr",
|
|
elfcpp::SHT_STRTAB,
|
|
elfcpp::SHF_ALLOC,
|
|
false,
|
|
ORDER_DYNAMIC_LINKER,
|
|
false, false, false);
|
|
*pdynstr = dynstr;
|
|
if (dynstr != NULL)
|
|
{
|
|
Output_section_data* strdata = new Output_data_strtab(&this->dynpool_);
|
|
dynstr->add_output_section_data(strdata);
|
|
|
|
if (dynsym != NULL)
|
|
dynsym->set_link_section(dynstr);
|
|
if (this->dynamic_section_ != NULL)
|
|
this->dynamic_section_->set_link_section(dynstr);
|
|
|
|
if (odyn != NULL)
|
|
{
|
|
odyn->add_section_address(elfcpp::DT_STRTAB, dynstr);
|
|
odyn->add_section_size(elfcpp::DT_STRSZ, dynstr);
|
|
}
|
|
}
|
|
|
|
// Create the hash tables. The Gnu-style hash table must be
|
|
// built first, because it changes the order of the symbols
|
|
// in the dynamic symbol table.
|
|
|
|
if (strcmp(parameters->options().hash_style(), "gnu") == 0
|
|
|| strcmp(parameters->options().hash_style(), "both") == 0)
|
|
{
|
|
unsigned char* phash;
|
|
unsigned int hashlen;
|
|
Dynobj::create_gnu_hash_table(*pdynamic_symbols,
|
|
local_symcount + forced_local_count,
|
|
&phash, &hashlen);
|
|
|
|
Output_section* hashsec =
|
|
this->choose_output_section(NULL, ".gnu.hash", elfcpp::SHT_GNU_HASH,
|
|
elfcpp::SHF_ALLOC, false,
|
|
ORDER_DYNAMIC_LINKER, false, false,
|
|
false);
|
|
|
|
Output_section_data* hashdata = new Output_data_const_buffer(phash,
|
|
hashlen,
|
|
align,
|
|
"** hash");
|
|
if (hashsec != NULL && hashdata != NULL)
|
|
hashsec->add_output_section_data(hashdata);
|
|
|
|
if (hashsec != NULL)
|
|
{
|
|
if (dynsym != NULL)
|
|
hashsec->set_link_section(dynsym);
|
|
|
|
// For a 64-bit target, the entries in .gnu.hash do not have
|
|
// a uniform size, so we only set the entry size for a
|
|
// 32-bit target.
|
|
if (parameters->target().get_size() == 32)
|
|
hashsec->set_entsize(4);
|
|
|
|
if (odyn != NULL)
|
|
odyn->add_section_address(elfcpp::DT_GNU_HASH, hashsec);
|
|
}
|
|
}
|
|
|
|
if (strcmp(parameters->options().hash_style(), "sysv") == 0
|
|
|| strcmp(parameters->options().hash_style(), "both") == 0)
|
|
{
|
|
unsigned char* phash;
|
|
unsigned int hashlen;
|
|
Dynobj::create_elf_hash_table(*pdynamic_symbols,
|
|
local_symcount + forced_local_count,
|
|
&phash, &hashlen);
|
|
|
|
Output_section* hashsec =
|
|
this->choose_output_section(NULL, ".hash", elfcpp::SHT_HASH,
|
|
elfcpp::SHF_ALLOC, false,
|
|
ORDER_DYNAMIC_LINKER, false, false,
|
|
false);
|
|
|
|
Output_section_data* hashdata = new Output_data_const_buffer(phash,
|
|
hashlen,
|
|
align,
|
|
"** hash");
|
|
if (hashsec != NULL && hashdata != NULL)
|
|
hashsec->add_output_section_data(hashdata);
|
|
|
|
if (hashsec != NULL)
|
|
{
|
|
if (dynsym != NULL)
|
|
hashsec->set_link_section(dynsym);
|
|
hashsec->set_entsize(parameters->target().hash_entry_size() / 8);
|
|
}
|
|
|
|
if (odyn != NULL)
|
|
odyn->add_section_address(elfcpp::DT_HASH, hashsec);
|
|
}
|
|
}
|
|
|
|
// Assign offsets to each local portion of the dynamic symbol table.
|
|
|
|
void
|
|
Layout::assign_local_dynsym_offsets(const Input_objects* input_objects)
|
|
{
|
|
Output_section* dynsym = this->dynsym_section_;
|
|
if (dynsym == NULL)
|
|
return;
|
|
|
|
off_t off = dynsym->offset();
|
|
|
|
// Skip the dummy symbol at the start of the section.
|
|
off += dynsym->entsize();
|
|
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
unsigned int count = (*p)->set_local_dynsym_offset(off);
|
|
off += count * dynsym->entsize();
|
|
}
|
|
}
|
|
|
|
// Create the version sections.
|
|
|
|
void
|
|
Layout::create_version_sections(const Versions* versions,
|
|
const Symbol_table* symtab,
|
|
unsigned int local_symcount,
|
|
const std::vector<Symbol*>& dynamic_symbols,
|
|
const Output_section* dynstr)
|
|
{
|
|
if (!versions->any_defs() && !versions->any_needs())
|
|
return;
|
|
|
|
switch (parameters->size_and_endianness())
|
|
{
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
case Parameters::TARGET_32_LITTLE:
|
|
this->sized_create_version_sections<32, false>(versions, symtab,
|
|
local_symcount,
|
|
dynamic_symbols, dynstr);
|
|
break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
case Parameters::TARGET_32_BIG:
|
|
this->sized_create_version_sections<32, true>(versions, symtab,
|
|
local_symcount,
|
|
dynamic_symbols, dynstr);
|
|
break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
case Parameters::TARGET_64_LITTLE:
|
|
this->sized_create_version_sections<64, false>(versions, symtab,
|
|
local_symcount,
|
|
dynamic_symbols, dynstr);
|
|
break;
|
|
#endif
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
case Parameters::TARGET_64_BIG:
|
|
this->sized_create_version_sections<64, true>(versions, symtab,
|
|
local_symcount,
|
|
dynamic_symbols, dynstr);
|
|
break;
|
|
#endif
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
}
|
|
|
|
// Create the version sections, sized version.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Layout::sized_create_version_sections(
|
|
const Versions* versions,
|
|
const Symbol_table* symtab,
|
|
unsigned int local_symcount,
|
|
const std::vector<Symbol*>& dynamic_symbols,
|
|
const Output_section* dynstr)
|
|
{
|
|
Output_section* vsec = this->choose_output_section(NULL, ".gnu.version",
|
|
elfcpp::SHT_GNU_versym,
|
|
elfcpp::SHF_ALLOC,
|
|
false,
|
|
ORDER_DYNAMIC_LINKER,
|
|
false, false, false);
|
|
|
|
// Check for NULL since a linker script may discard this section.
|
|
if (vsec != NULL)
|
|
{
|
|
unsigned char* vbuf;
|
|
unsigned int vsize;
|
|
versions->symbol_section_contents<size, big_endian>(symtab,
|
|
&this->dynpool_,
|
|
local_symcount,
|
|
dynamic_symbols,
|
|
&vbuf, &vsize);
|
|
|
|
Output_section_data* vdata = new Output_data_const_buffer(vbuf, vsize, 2,
|
|
"** versions");
|
|
|
|
vsec->add_output_section_data(vdata);
|
|
vsec->set_entsize(2);
|
|
vsec->set_link_section(this->dynsym_section_);
|
|
}
|
|
|
|
Output_data_dynamic* const odyn = this->dynamic_data_;
|
|
if (odyn != NULL && vsec != NULL)
|
|
odyn->add_section_address(elfcpp::DT_VERSYM, vsec);
|
|
|
|
if (versions->any_defs())
|
|
{
|
|
Output_section* vdsec;
|
|
vdsec = this->choose_output_section(NULL, ".gnu.version_d",
|
|
elfcpp::SHT_GNU_verdef,
|
|
elfcpp::SHF_ALLOC,
|
|
false, ORDER_DYNAMIC_LINKER, false,
|
|
false, false);
|
|
|
|
if (vdsec != NULL)
|
|
{
|
|
unsigned char* vdbuf;
|
|
unsigned int vdsize;
|
|
unsigned int vdentries;
|
|
versions->def_section_contents<size, big_endian>(&this->dynpool_,
|
|
&vdbuf, &vdsize,
|
|
&vdentries);
|
|
|
|
Output_section_data* vddata =
|
|
new Output_data_const_buffer(vdbuf, vdsize, 4, "** version defs");
|
|
|
|
vdsec->add_output_section_data(vddata);
|
|
vdsec->set_link_section(dynstr);
|
|
vdsec->set_info(vdentries);
|
|
|
|
if (odyn != NULL)
|
|
{
|
|
odyn->add_section_address(elfcpp::DT_VERDEF, vdsec);
|
|
odyn->add_constant(elfcpp::DT_VERDEFNUM, vdentries);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (versions->any_needs())
|
|
{
|
|
Output_section* vnsec;
|
|
vnsec = this->choose_output_section(NULL, ".gnu.version_r",
|
|
elfcpp::SHT_GNU_verneed,
|
|
elfcpp::SHF_ALLOC,
|
|
false, ORDER_DYNAMIC_LINKER, false,
|
|
false, false);
|
|
|
|
if (vnsec != NULL)
|
|
{
|
|
unsigned char* vnbuf;
|
|
unsigned int vnsize;
|
|
unsigned int vnentries;
|
|
versions->need_section_contents<size, big_endian>(&this->dynpool_,
|
|
&vnbuf, &vnsize,
|
|
&vnentries);
|
|
|
|
Output_section_data* vndata =
|
|
new Output_data_const_buffer(vnbuf, vnsize, 4, "** version refs");
|
|
|
|
vnsec->add_output_section_data(vndata);
|
|
vnsec->set_link_section(dynstr);
|
|
vnsec->set_info(vnentries);
|
|
|
|
if (odyn != NULL)
|
|
{
|
|
odyn->add_section_address(elfcpp::DT_VERNEED, vnsec);
|
|
odyn->add_constant(elfcpp::DT_VERNEEDNUM, vnentries);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Create the .interp section and PT_INTERP segment.
|
|
|
|
void
|
|
Layout::create_interp(const Target* target)
|
|
{
|
|
gold_assert(this->interp_segment_ == NULL);
|
|
|
|
const char* interp = parameters->options().dynamic_linker();
|
|
if (interp == NULL)
|
|
{
|
|
interp = target->dynamic_linker();
|
|
gold_assert(interp != NULL);
|
|
}
|
|
|
|
size_t len = strlen(interp) + 1;
|
|
|
|
Output_section_data* odata = new Output_data_const(interp, len, 1);
|
|
|
|
Output_section* osec = this->choose_output_section(NULL, ".interp",
|
|
elfcpp::SHT_PROGBITS,
|
|
elfcpp::SHF_ALLOC,
|
|
false, ORDER_INTERP,
|
|
false, false, false);
|
|
if (osec != NULL)
|
|
osec->add_output_section_data(odata);
|
|
}
|
|
|
|
// Add dynamic tags for the PLT and the dynamic relocs. This is
|
|
// called by the target-specific code. This does nothing if not doing
|
|
// a dynamic link.
|
|
|
|
// USE_REL is true for REL relocs rather than RELA relocs.
|
|
|
|
// If PLT_GOT is not NULL, then DT_PLTGOT points to it.
|
|
|
|
// If PLT_REL is not NULL, it is used for DT_PLTRELSZ, and DT_JMPREL,
|
|
// and we also set DT_PLTREL. We use PLT_REL's output section, since
|
|
// some targets have multiple reloc sections in PLT_REL.
|
|
|
|
// If DYN_REL is not NULL, it is used for DT_REL/DT_RELA,
|
|
// DT_RELSZ/DT_RELASZ, DT_RELENT/DT_RELAENT. Again we use the output
|
|
// section.
|
|
|
|
// If ADD_DEBUG is true, we add a DT_DEBUG entry when generating an
|
|
// executable.
|
|
|
|
void
|
|
Layout::add_target_dynamic_tags(bool use_rel, const Output_data* plt_got,
|
|
const Output_data* plt_rel,
|
|
const Output_data_reloc_generic* dyn_rel,
|
|
bool add_debug, bool dynrel_includes_plt)
|
|
{
|
|
Output_data_dynamic* odyn = this->dynamic_data_;
|
|
if (odyn == NULL)
|
|
return;
|
|
|
|
if (plt_got != NULL && plt_got->output_section() != NULL)
|
|
odyn->add_section_address(elfcpp::DT_PLTGOT, plt_got);
|
|
|
|
if (plt_rel != NULL && plt_rel->output_section() != NULL)
|
|
{
|
|
odyn->add_section_size(elfcpp::DT_PLTRELSZ, plt_rel->output_section());
|
|
odyn->add_section_address(elfcpp::DT_JMPREL, plt_rel->output_section());
|
|
odyn->add_constant(elfcpp::DT_PLTREL,
|
|
use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA);
|
|
}
|
|
|
|
if ((dyn_rel != NULL && dyn_rel->output_section() != NULL)
|
|
|| (dynrel_includes_plt
|
|
&& plt_rel != NULL
|
|
&& plt_rel->output_section() != NULL))
|
|
{
|
|
bool have_dyn_rel = dyn_rel != NULL && dyn_rel->output_section() != NULL;
|
|
bool have_plt_rel = plt_rel != NULL && plt_rel->output_section() != NULL;
|
|
odyn->add_section_address(use_rel ? elfcpp::DT_REL : elfcpp::DT_RELA,
|
|
(have_dyn_rel
|
|
? dyn_rel->output_section()
|
|
: plt_rel->output_section()));
|
|
elfcpp::DT size_tag = use_rel ? elfcpp::DT_RELSZ : elfcpp::DT_RELASZ;
|
|
if (have_dyn_rel && have_plt_rel && dynrel_includes_plt)
|
|
odyn->add_section_size(size_tag,
|
|
dyn_rel->output_section(),
|
|
plt_rel->output_section());
|
|
else if (have_dyn_rel)
|
|
odyn->add_section_size(size_tag, dyn_rel->output_section());
|
|
else
|
|
odyn->add_section_size(size_tag, plt_rel->output_section());
|
|
const int size = parameters->target().get_size();
|
|
elfcpp::DT rel_tag;
|
|
int rel_size;
|
|
if (use_rel)
|
|
{
|
|
rel_tag = elfcpp::DT_RELENT;
|
|
if (size == 32)
|
|
rel_size = Reloc_types<elfcpp::SHT_REL, 32, false>::reloc_size;
|
|
else if (size == 64)
|
|
rel_size = Reloc_types<elfcpp::SHT_REL, 64, false>::reloc_size;
|
|
else
|
|
gold_unreachable();
|
|
}
|
|
else
|
|
{
|
|
rel_tag = elfcpp::DT_RELAENT;
|
|
if (size == 32)
|
|
rel_size = Reloc_types<elfcpp::SHT_RELA, 32, false>::reloc_size;
|
|
else if (size == 64)
|
|
rel_size = Reloc_types<elfcpp::SHT_RELA, 64, false>::reloc_size;
|
|
else
|
|
gold_unreachable();
|
|
}
|
|
odyn->add_constant(rel_tag, rel_size);
|
|
|
|
if (parameters->options().combreloc() && have_dyn_rel)
|
|
{
|
|
size_t c = dyn_rel->relative_reloc_count();
|
|
if (c > 0)
|
|
odyn->add_constant((use_rel
|
|
? elfcpp::DT_RELCOUNT
|
|
: elfcpp::DT_RELACOUNT),
|
|
c);
|
|
}
|
|
}
|
|
|
|
if (add_debug && !parameters->options().shared())
|
|
{
|
|
// The value of the DT_DEBUG tag is filled in by the dynamic
|
|
// linker at run time, and used by the debugger.
|
|
odyn->add_constant(elfcpp::DT_DEBUG, 0);
|
|
}
|
|
}
|
|
|
|
void
|
|
Layout::add_target_specific_dynamic_tag(elfcpp::DT tag, unsigned int val)
|
|
{
|
|
Output_data_dynamic* odyn = this->dynamic_data_;
|
|
if (odyn == NULL)
|
|
return;
|
|
odyn->add_constant(tag, val);
|
|
}
|
|
|
|
// Finish the .dynamic section and PT_DYNAMIC segment.
|
|
|
|
void
|
|
Layout::finish_dynamic_section(const Input_objects* input_objects,
|
|
const Symbol_table* symtab)
|
|
{
|
|
if (!this->script_options_->saw_phdrs_clause()
|
|
&& this->dynamic_section_ != NULL)
|
|
{
|
|
Output_segment* oseg = this->make_output_segment(elfcpp::PT_DYNAMIC,
|
|
(elfcpp::PF_R
|
|
| elfcpp::PF_W));
|
|
oseg->add_output_section_to_nonload(this->dynamic_section_,
|
|
elfcpp::PF_R | elfcpp::PF_W);
|
|
}
|
|
|
|
Output_data_dynamic* const odyn = this->dynamic_data_;
|
|
if (odyn == NULL)
|
|
return;
|
|
|
|
for (Input_objects::Dynobj_iterator p = input_objects->dynobj_begin();
|
|
p != input_objects->dynobj_end();
|
|
++p)
|
|
{
|
|
if (!(*p)->is_needed() && (*p)->as_needed())
|
|
{
|
|
// This dynamic object was linked with --as-needed, but it
|
|
// is not needed.
|
|
continue;
|
|
}
|
|
|
|
odyn->add_string(elfcpp::DT_NEEDED, (*p)->soname());
|
|
}
|
|
|
|
if (parameters->options().shared())
|
|
{
|
|
const char* soname = parameters->options().soname();
|
|
if (soname != NULL)
|
|
odyn->add_string(elfcpp::DT_SONAME, soname);
|
|
}
|
|
|
|
Symbol* sym = symtab->lookup(parameters->options().init());
|
|
if (sym != NULL && sym->is_defined() && !sym->is_from_dynobj())
|
|
odyn->add_symbol(elfcpp::DT_INIT, sym);
|
|
|
|
sym = symtab->lookup(parameters->options().fini());
|
|
if (sym != NULL && sym->is_defined() && !sym->is_from_dynobj())
|
|
odyn->add_symbol(elfcpp::DT_FINI, sym);
|
|
|
|
// Look for .init_array, .preinit_array and .fini_array by checking
|
|
// section types.
|
|
for(Layout::Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
switch((*p)->type())
|
|
{
|
|
case elfcpp::SHT_FINI_ARRAY:
|
|
odyn->add_section_address(elfcpp::DT_FINI_ARRAY, *p);
|
|
odyn->add_section_size(elfcpp::DT_FINI_ARRAYSZ, *p);
|
|
break;
|
|
case elfcpp::SHT_INIT_ARRAY:
|
|
odyn->add_section_address(elfcpp::DT_INIT_ARRAY, *p);
|
|
odyn->add_section_size(elfcpp::DT_INIT_ARRAYSZ, *p);
|
|
break;
|
|
case elfcpp::SHT_PREINIT_ARRAY:
|
|
odyn->add_section_address(elfcpp::DT_PREINIT_ARRAY, *p);
|
|
odyn->add_section_size(elfcpp::DT_PREINIT_ARRAYSZ, *p);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
// Add a DT_RPATH entry if needed.
|
|
const General_options::Dir_list& rpath(parameters->options().rpath());
|
|
if (!rpath.empty())
|
|
{
|
|
std::string rpath_val;
|
|
for (General_options::Dir_list::const_iterator p = rpath.begin();
|
|
p != rpath.end();
|
|
++p)
|
|
{
|
|
if (rpath_val.empty())
|
|
rpath_val = p->name();
|
|
else
|
|
{
|
|
// Eliminate duplicates.
|
|
General_options::Dir_list::const_iterator q;
|
|
for (q = rpath.begin(); q != p; ++q)
|
|
if (q->name() == p->name())
|
|
break;
|
|
if (q == p)
|
|
{
|
|
rpath_val += ':';
|
|
rpath_val += p->name();
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!parameters->options().enable_new_dtags())
|
|
odyn->add_string(elfcpp::DT_RPATH, rpath_val);
|
|
else
|
|
odyn->add_string(elfcpp::DT_RUNPATH, rpath_val);
|
|
}
|
|
|
|
// Look for text segments that have dynamic relocations.
|
|
bool have_textrel = false;
|
|
if (!this->script_options_->saw_sections_clause())
|
|
{
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD
|
|
&& ((*p)->flags() & elfcpp::PF_W) == 0
|
|
&& (*p)->has_dynamic_reloc())
|
|
{
|
|
have_textrel = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// We don't know the section -> segment mapping, so we are
|
|
// conservative and just look for readonly sections with
|
|
// relocations. If those sections wind up in writable segments,
|
|
// then we have created an unnecessary DT_TEXTREL entry.
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0
|
|
&& ((*p)->flags() & elfcpp::SHF_WRITE) == 0
|
|
&& (*p)->has_dynamic_reloc())
|
|
{
|
|
have_textrel = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (parameters->options().filter() != NULL)
|
|
odyn->add_string(elfcpp::DT_FILTER, parameters->options().filter());
|
|
if (parameters->options().any_auxiliary())
|
|
{
|
|
for (options::String_set::const_iterator p =
|
|
parameters->options().auxiliary_begin();
|
|
p != parameters->options().auxiliary_end();
|
|
++p)
|
|
odyn->add_string(elfcpp::DT_AUXILIARY, *p);
|
|
}
|
|
|
|
// Add a DT_FLAGS entry if necessary.
|
|
unsigned int flags = 0;
|
|
if (have_textrel)
|
|
{
|
|
// Add a DT_TEXTREL for compatibility with older loaders.
|
|
odyn->add_constant(elfcpp::DT_TEXTREL, 0);
|
|
flags |= elfcpp::DF_TEXTREL;
|
|
|
|
if (parameters->options().text())
|
|
gold_error(_("read-only segment has dynamic relocations"));
|
|
else if (parameters->options().warn_shared_textrel()
|
|
&& parameters->options().shared())
|
|
gold_warning(_("shared library text segment is not shareable"));
|
|
}
|
|
if (parameters->options().shared() && this->has_static_tls())
|
|
flags |= elfcpp::DF_STATIC_TLS;
|
|
if (parameters->options().origin())
|
|
flags |= elfcpp::DF_ORIGIN;
|
|
if (parameters->options().Bsymbolic()
|
|
&& !parameters->options().have_dynamic_list())
|
|
{
|
|
flags |= elfcpp::DF_SYMBOLIC;
|
|
// Add DT_SYMBOLIC for compatibility with older loaders.
|
|
odyn->add_constant(elfcpp::DT_SYMBOLIC, 0);
|
|
}
|
|
if (parameters->options().now())
|
|
flags |= elfcpp::DF_BIND_NOW;
|
|
if (flags != 0)
|
|
odyn->add_constant(elfcpp::DT_FLAGS, flags);
|
|
|
|
flags = 0;
|
|
if (parameters->options().global())
|
|
flags |= elfcpp::DF_1_GLOBAL;
|
|
if (parameters->options().initfirst())
|
|
flags |= elfcpp::DF_1_INITFIRST;
|
|
if (parameters->options().interpose())
|
|
flags |= elfcpp::DF_1_INTERPOSE;
|
|
if (parameters->options().loadfltr())
|
|
flags |= elfcpp::DF_1_LOADFLTR;
|
|
if (parameters->options().nodefaultlib())
|
|
flags |= elfcpp::DF_1_NODEFLIB;
|
|
if (parameters->options().nodelete())
|
|
flags |= elfcpp::DF_1_NODELETE;
|
|
if (parameters->options().nodlopen())
|
|
flags |= elfcpp::DF_1_NOOPEN;
|
|
if (parameters->options().nodump())
|
|
flags |= elfcpp::DF_1_NODUMP;
|
|
if (!parameters->options().shared())
|
|
flags &= ~(elfcpp::DF_1_INITFIRST
|
|
| elfcpp::DF_1_NODELETE
|
|
| elfcpp::DF_1_NOOPEN);
|
|
if (parameters->options().origin())
|
|
flags |= elfcpp::DF_1_ORIGIN;
|
|
if (parameters->options().now())
|
|
flags |= elfcpp::DF_1_NOW;
|
|
if (parameters->options().Bgroup())
|
|
flags |= elfcpp::DF_1_GROUP;
|
|
if (parameters->options().pie())
|
|
flags |= elfcpp::DF_1_PIE;
|
|
if (flags != 0)
|
|
odyn->add_constant(elfcpp::DT_FLAGS_1, flags);
|
|
|
|
flags = 0;
|
|
if (parameters->options().unique())
|
|
flags |= elfcpp::DF_GNU_1_UNIQUE;
|
|
if (flags != 0)
|
|
odyn->add_constant(elfcpp::DT_GNU_FLAGS_1, flags);
|
|
}
|
|
|
|
// Set the size of the _DYNAMIC symbol table to be the size of the
|
|
// dynamic data.
|
|
|
|
void
|
|
Layout::set_dynamic_symbol_size(const Symbol_table* symtab)
|
|
{
|
|
Output_data_dynamic* const odyn = this->dynamic_data_;
|
|
if (odyn == NULL)
|
|
return;
|
|
odyn->finalize_data_size();
|
|
if (this->dynamic_symbol_ == NULL)
|
|
return;
|
|
off_t data_size = odyn->data_size();
|
|
const int size = parameters->target().get_size();
|
|
if (size == 32)
|
|
symtab->get_sized_symbol<32>(this->dynamic_symbol_)->set_symsize(data_size);
|
|
else if (size == 64)
|
|
symtab->get_sized_symbol<64>(this->dynamic_symbol_)->set_symsize(data_size);
|
|
else
|
|
gold_unreachable();
|
|
}
|
|
|
|
// The mapping of input section name prefixes to output section names.
|
|
// In some cases one prefix is itself a prefix of another prefix; in
|
|
// such a case the longer prefix must come first. These prefixes are
|
|
// based on the GNU linker default ELF linker script.
|
|
|
|
#define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
|
|
#define MAPPING_INIT_EXACT(f, t) { f, 0, t, sizeof(t) - 1 }
|
|
const Layout::Section_name_mapping Layout::section_name_mapping[] =
|
|
{
|
|
MAPPING_INIT(".text.", ".text"),
|
|
MAPPING_INIT(".rodata.", ".rodata"),
|
|
MAPPING_INIT(".data.rel.ro.local.", ".data.rel.ro.local"),
|
|
MAPPING_INIT_EXACT(".data.rel.ro.local", ".data.rel.ro.local"),
|
|
MAPPING_INIT(".data.rel.ro.", ".data.rel.ro"),
|
|
MAPPING_INIT_EXACT(".data.rel.ro", ".data.rel.ro"),
|
|
MAPPING_INIT(".data.", ".data"),
|
|
MAPPING_INIT(".bss.", ".bss"),
|
|
MAPPING_INIT(".tdata.", ".tdata"),
|
|
MAPPING_INIT(".tbss.", ".tbss"),
|
|
MAPPING_INIT(".init_array.", ".init_array"),
|
|
MAPPING_INIT(".fini_array.", ".fini_array"),
|
|
MAPPING_INIT(".sdata.", ".sdata"),
|
|
MAPPING_INIT(".sbss.", ".sbss"),
|
|
// FIXME: In the GNU linker, .sbss2 and .sdata2 are handled
|
|
// differently depending on whether it is creating a shared library.
|
|
MAPPING_INIT(".sdata2.", ".sdata"),
|
|
MAPPING_INIT(".sbss2.", ".sbss"),
|
|
MAPPING_INIT(".lrodata.", ".lrodata"),
|
|
MAPPING_INIT(".ldata.", ".ldata"),
|
|
MAPPING_INIT(".lbss.", ".lbss"),
|
|
MAPPING_INIT(".gcc_except_table.", ".gcc_except_table"),
|
|
MAPPING_INIT(".gnu.linkonce.d.rel.ro.local.", ".data.rel.ro.local"),
|
|
MAPPING_INIT(".gnu.linkonce.d.rel.ro.", ".data.rel.ro"),
|
|
MAPPING_INIT(".gnu.linkonce.t.", ".text"),
|
|
MAPPING_INIT(".gnu.linkonce.r.", ".rodata"),
|
|
MAPPING_INIT(".gnu.linkonce.d.", ".data"),
|
|
MAPPING_INIT(".gnu.linkonce.b.", ".bss"),
|
|
MAPPING_INIT(".gnu.linkonce.s.", ".sdata"),
|
|
MAPPING_INIT(".gnu.linkonce.sb.", ".sbss"),
|
|
MAPPING_INIT(".gnu.linkonce.s2.", ".sdata"),
|
|
MAPPING_INIT(".gnu.linkonce.sb2.", ".sbss"),
|
|
MAPPING_INIT(".gnu.linkonce.wi.", ".debug_info"),
|
|
MAPPING_INIT(".gnu.linkonce.td.", ".tdata"),
|
|
MAPPING_INIT(".gnu.linkonce.tb.", ".tbss"),
|
|
MAPPING_INIT(".gnu.linkonce.lr.", ".lrodata"),
|
|
MAPPING_INIT(".gnu.linkonce.l.", ".ldata"),
|
|
MAPPING_INIT(".gnu.linkonce.lb.", ".lbss"),
|
|
MAPPING_INIT(".ARM.extab", ".ARM.extab"),
|
|
MAPPING_INIT(".gnu.linkonce.armextab.", ".ARM.extab"),
|
|
MAPPING_INIT(".ARM.exidx", ".ARM.exidx"),
|
|
MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
|
|
MAPPING_INIT(".gnu.build.attributes.", ".gnu.build.attributes"),
|
|
};
|
|
|
|
// Mapping for ".text" section prefixes with -z,keep-text-section-prefix.
|
|
const Layout::Section_name_mapping Layout::text_section_name_mapping[] =
|
|
{
|
|
MAPPING_INIT(".text.hot.", ".text.hot"),
|
|
MAPPING_INIT_EXACT(".text.hot", ".text.hot"),
|
|
MAPPING_INIT(".text.unlikely.", ".text.unlikely"),
|
|
MAPPING_INIT_EXACT(".text.unlikely", ".text.unlikely"),
|
|
MAPPING_INIT(".text.startup.", ".text.startup"),
|
|
MAPPING_INIT_EXACT(".text.startup", ".text.startup"),
|
|
MAPPING_INIT(".text.exit.", ".text.exit"),
|
|
MAPPING_INIT_EXACT(".text.exit", ".text.exit"),
|
|
MAPPING_INIT(".text.", ".text"),
|
|
};
|
|
#undef MAPPING_INIT
|
|
#undef MAPPING_INIT_EXACT
|
|
|
|
const int Layout::section_name_mapping_count =
|
|
(sizeof(Layout::section_name_mapping)
|
|
/ sizeof(Layout::section_name_mapping[0]));
|
|
|
|
const int Layout::text_section_name_mapping_count =
|
|
(sizeof(Layout::text_section_name_mapping)
|
|
/ sizeof(Layout::text_section_name_mapping[0]));
|
|
|
|
// Find section name NAME in PSNM and return the mapped name if found
|
|
// with the length set in PLEN.
|
|
const char *
|
|
Layout::match_section_name(const Layout::Section_name_mapping* psnm,
|
|
const int count,
|
|
const char* name, size_t* plen)
|
|
{
|
|
for (int i = 0; i < count; ++i, ++psnm)
|
|
{
|
|
if (psnm->fromlen > 0)
|
|
{
|
|
if (strncmp(name, psnm->from, psnm->fromlen) == 0)
|
|
{
|
|
*plen = psnm->tolen;
|
|
return psnm->to;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (strcmp(name, psnm->from) == 0)
|
|
{
|
|
*plen = psnm->tolen;
|
|
return psnm->to;
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
// Choose the output section name to use given an input section name.
|
|
// Set *PLEN to the length of the name. *PLEN is initialized to the
|
|
// length of NAME.
|
|
|
|
const char*
|
|
Layout::output_section_name(const Relobj* relobj, const char* name,
|
|
size_t* plen)
|
|
{
|
|
// gcc 4.3 generates the following sorts of section names when it
|
|
// needs a section name specific to a function:
|
|
// .text.FN
|
|
// .rodata.FN
|
|
// .sdata2.FN
|
|
// .data.FN
|
|
// .data.rel.FN
|
|
// .data.rel.local.FN
|
|
// .data.rel.ro.FN
|
|
// .data.rel.ro.local.FN
|
|
// .sdata.FN
|
|
// .bss.FN
|
|
// .sbss.FN
|
|
// .tdata.FN
|
|
// .tbss.FN
|
|
|
|
// The GNU linker maps all of those to the part before the .FN,
|
|
// except that .data.rel.local.FN is mapped to .data, and
|
|
// .data.rel.ro.local.FN is mapped to .data.rel.ro. The sections
|
|
// beginning with .data.rel.ro.local are grouped together.
|
|
|
|
// For an anonymous namespace, the string FN can contain a '.'.
|
|
|
|
// Also of interest: .rodata.strN.N, .rodata.cstN, both of which the
|
|
// GNU linker maps to .rodata.
|
|
|
|
// The .data.rel.ro sections are used with -z relro. The sections
|
|
// are recognized by name. We use the same names that the GNU
|
|
// linker does for these sections.
|
|
|
|
// It is hard to handle this in a principled way, so we don't even
|
|
// try. We use a table of mappings. If the input section name is
|
|
// not found in the table, we simply use it as the output section
|
|
// name.
|
|
|
|
if (parameters->options().keep_text_section_prefix()
|
|
&& is_prefix_of(".text", name))
|
|
{
|
|
const char* match = match_section_name(text_section_name_mapping,
|
|
text_section_name_mapping_count,
|
|
name, plen);
|
|
if (match != NULL)
|
|
return match;
|
|
}
|
|
|
|
const char* match = match_section_name(section_name_mapping,
|
|
section_name_mapping_count, name, plen);
|
|
if (match != NULL)
|
|
return match;
|
|
|
|
// As an additional complication, .ctors sections are output in
|
|
// either .ctors or .init_array sections, and .dtors sections are
|
|
// output in either .dtors or .fini_array sections.
|
|
if (is_prefix_of(".ctors.", name) || is_prefix_of(".dtors.", name))
|
|
{
|
|
if (parameters->options().ctors_in_init_array())
|
|
{
|
|
*plen = 11;
|
|
return name[1] == 'c' ? ".init_array" : ".fini_array";
|
|
}
|
|
else
|
|
{
|
|
*plen = 6;
|
|
return name[1] == 'c' ? ".ctors" : ".dtors";
|
|
}
|
|
}
|
|
if (parameters->options().ctors_in_init_array()
|
|
&& (strcmp(name, ".ctors") == 0 || strcmp(name, ".dtors") == 0))
|
|
{
|
|
// To make .init_array/.fini_array work with gcc we must exclude
|
|
// .ctors and .dtors sections from the crtbegin and crtend
|
|
// files.
|
|
if (relobj == NULL
|
|
|| (!Layout::match_file_name(relobj, "crtbegin")
|
|
&& !Layout::match_file_name(relobj, "crtend")))
|
|
{
|
|
*plen = 11;
|
|
return name[1] == 'c' ? ".init_array" : ".fini_array";
|
|
}
|
|
}
|
|
|
|
return name;
|
|
}
|
|
|
|
// Return true if RELOBJ is an input file whose base name matches
|
|
// FILE_NAME. The base name must have an extension of ".o", and must
|
|
// be exactly FILE_NAME.o or FILE_NAME, one character, ".o". This is
|
|
// to match crtbegin.o as well as crtbeginS.o without getting confused
|
|
// by other possibilities. Overall matching the file name this way is
|
|
// a dreadful hack, but the GNU linker does it in order to better
|
|
// support gcc, and we need to be compatible.
|
|
|
|
bool
|
|
Layout::match_file_name(const Relobj* relobj, const char* match)
|
|
{
|
|
const std::string& file_name(relobj->name());
|
|
const char* base_name = lbasename(file_name.c_str());
|
|
size_t match_len = strlen(match);
|
|
if (strncmp(base_name, match, match_len) != 0)
|
|
return false;
|
|
size_t base_len = strlen(base_name);
|
|
if (base_len != match_len + 2 && base_len != match_len + 3)
|
|
return false;
|
|
return memcmp(base_name + base_len - 2, ".o", 2) == 0;
|
|
}
|
|
|
|
// Check if a comdat group or .gnu.linkonce section with the given
|
|
// NAME is selected for the link. If there is already a section,
|
|
// *KEPT_SECTION is set to point to the existing section and the
|
|
// function returns false. Otherwise, OBJECT, SHNDX, IS_COMDAT, and
|
|
// IS_GROUP_NAME are recorded for this NAME in the layout object,
|
|
// *KEPT_SECTION is set to the internal copy and the function returns
|
|
// true.
|
|
|
|
bool
|
|
Layout::find_or_add_kept_section(const std::string& name,
|
|
Relobj* object,
|
|
unsigned int shndx,
|
|
bool is_comdat,
|
|
bool is_group_name,
|
|
Kept_section** kept_section)
|
|
{
|
|
// It's normal to see a couple of entries here, for the x86 thunk
|
|
// sections. If we see more than a few, we're linking a C++
|
|
// program, and we resize to get more space to minimize rehashing.
|
|
if (this->signatures_.size() > 4
|
|
&& !this->resized_signatures_)
|
|
{
|
|
reserve_unordered_map(&this->signatures_,
|
|
this->number_of_input_files_ * 64);
|
|
this->resized_signatures_ = true;
|
|
}
|
|
|
|
Kept_section candidate;
|
|
std::pair<Signatures::iterator, bool> ins =
|
|
this->signatures_.insert(std::make_pair(name, candidate));
|
|
|
|
if (kept_section != NULL)
|
|
*kept_section = &ins.first->second;
|
|
if (ins.second)
|
|
{
|
|
// This is the first time we've seen this signature.
|
|
ins.first->second.set_object(object);
|
|
ins.first->second.set_shndx(shndx);
|
|
if (is_comdat)
|
|
ins.first->second.set_is_comdat();
|
|
if (is_group_name)
|
|
ins.first->second.set_is_group_name();
|
|
return true;
|
|
}
|
|
|
|
// We have already seen this signature.
|
|
|
|
if (ins.first->second.is_group_name())
|
|
{
|
|
// We've already seen a real section group with this signature.
|
|
// If the kept group is from a plugin object, and we're in the
|
|
// replacement phase, accept the new one as a replacement.
|
|
if (ins.first->second.object() == NULL
|
|
&& parameters->options().plugins()->in_replacement_phase())
|
|
{
|
|
ins.first->second.set_object(object);
|
|
ins.first->second.set_shndx(shndx);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
else if (is_group_name)
|
|
{
|
|
// This is a real section group, and we've already seen a
|
|
// linkonce section with this signature. Record that we've seen
|
|
// a section group, and don't include this section group.
|
|
ins.first->second.set_is_group_name();
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
// We've already seen a linkonce section and this is a linkonce
|
|
// section. These don't block each other--this may be the same
|
|
// symbol name with different section types.
|
|
return true;
|
|
}
|
|
}
|
|
|
|
// Store the allocated sections into the section list.
|
|
|
|
void
|
|
Layout::get_allocated_sections(Section_list* section_list) const
|
|
{
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0)
|
|
section_list->push_back(*p);
|
|
}
|
|
|
|
// Store the executable sections into the section list.
|
|
|
|
void
|
|
Layout::get_executable_sections(Section_list* section_list) const
|
|
{
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
if (((*p)->flags() & (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR))
|
|
== (elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR))
|
|
section_list->push_back(*p);
|
|
}
|
|
|
|
// Create an output segment.
|
|
|
|
Output_segment*
|
|
Layout::make_output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags)
|
|
{
|
|
gold_assert(!parameters->options().relocatable());
|
|
Output_segment* oseg = new Output_segment(type, flags);
|
|
this->segment_list_.push_back(oseg);
|
|
|
|
if (type == elfcpp::PT_TLS)
|
|
this->tls_segment_ = oseg;
|
|
else if (type == elfcpp::PT_GNU_RELRO)
|
|
this->relro_segment_ = oseg;
|
|
else if (type == elfcpp::PT_INTERP)
|
|
this->interp_segment_ = oseg;
|
|
|
|
return oseg;
|
|
}
|
|
|
|
// Return the file offset of the normal symbol table.
|
|
|
|
off_t
|
|
Layout::symtab_section_offset() const
|
|
{
|
|
if (this->symtab_section_ != NULL)
|
|
return this->symtab_section_->offset();
|
|
return 0;
|
|
}
|
|
|
|
// Return the section index of the normal symbol table. It may have
|
|
// been stripped by the -s/--strip-all option.
|
|
|
|
unsigned int
|
|
Layout::symtab_section_shndx() const
|
|
{
|
|
if (this->symtab_section_ != NULL)
|
|
return this->symtab_section_->out_shndx();
|
|
return 0;
|
|
}
|
|
|
|
// Write out the Output_sections. Most won't have anything to write,
|
|
// since most of the data will come from input sections which are
|
|
// handled elsewhere. But some Output_sections do have Output_data.
|
|
|
|
void
|
|
Layout::write_output_sections(Output_file* of) const
|
|
{
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if (!(*p)->after_input_sections())
|
|
(*p)->write(of);
|
|
}
|
|
}
|
|
|
|
// Write out data not associated with a section or the symbol table.
|
|
|
|
void
|
|
Layout::write_data(const Symbol_table* symtab, Output_file* of) const
|
|
{
|
|
if (!parameters->options().strip_all())
|
|
{
|
|
const Output_section* symtab_section = this->symtab_section_;
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->needs_symtab_index())
|
|
{
|
|
gold_assert(symtab_section != NULL);
|
|
unsigned int index = (*p)->symtab_index();
|
|
gold_assert(index > 0 && index != -1U);
|
|
off_t off = (symtab_section->offset()
|
|
+ index * symtab_section->entsize());
|
|
symtab->write_section_symbol(*p, this->symtab_xindex_, of, off);
|
|
}
|
|
}
|
|
}
|
|
|
|
const Output_section* dynsym_section = this->dynsym_section_;
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->needs_dynsym_index())
|
|
{
|
|
gold_assert(dynsym_section != NULL);
|
|
unsigned int index = (*p)->dynsym_index();
|
|
gold_assert(index > 0 && index != -1U);
|
|
off_t off = (dynsym_section->offset()
|
|
+ index * dynsym_section->entsize());
|
|
symtab->write_section_symbol(*p, this->dynsym_xindex_, of, off);
|
|
}
|
|
}
|
|
|
|
// Write out the Output_data which are not in an Output_section.
|
|
for (Data_list::const_iterator p = this->special_output_list_.begin();
|
|
p != this->special_output_list_.end();
|
|
++p)
|
|
(*p)->write(of);
|
|
|
|
// Write out the Output_data which are not in an Output_section
|
|
// and are regenerated in each iteration of relaxation.
|
|
for (Data_list::const_iterator p = this->relax_output_list_.begin();
|
|
p != this->relax_output_list_.end();
|
|
++p)
|
|
(*p)->write(of);
|
|
}
|
|
|
|
// Write out the Output_sections which can only be written after the
|
|
// input sections are complete.
|
|
|
|
void
|
|
Layout::write_sections_after_input_sections(Output_file* of)
|
|
{
|
|
// Determine the final section offsets, and thus the final output
|
|
// file size. Note we finalize the .shstrab last, to allow the
|
|
// after_input_section sections to modify their section-names before
|
|
// writing.
|
|
if (this->any_postprocessing_sections_)
|
|
{
|
|
off_t off = this->output_file_size_;
|
|
off = this->set_section_offsets(off, POSTPROCESSING_SECTIONS_PASS);
|
|
|
|
// Now that we've finalized the names, we can finalize the shstrab.
|
|
off =
|
|
this->set_section_offsets(off,
|
|
STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS);
|
|
|
|
if (off > this->output_file_size_)
|
|
{
|
|
of->resize(off);
|
|
this->output_file_size_ = off;
|
|
}
|
|
}
|
|
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->after_input_sections())
|
|
(*p)->write(of);
|
|
}
|
|
|
|
this->section_headers_->write(of);
|
|
}
|
|
|
|
// If a tree-style build ID was requested, the parallel part of that computation
|
|
// is already done, and the final hash-of-hashes is computed here. For other
|
|
// types of build IDs, all the work is done here.
|
|
|
|
void
|
|
Layout::write_build_id(Output_file* of, unsigned char* array_of_hashes,
|
|
size_t size_of_hashes) const
|
|
{
|
|
if (this->build_id_note_ == NULL)
|
|
return;
|
|
|
|
unsigned char* ov = of->get_output_view(this->build_id_note_->offset(),
|
|
this->build_id_note_->data_size());
|
|
|
|
if (array_of_hashes == NULL)
|
|
{
|
|
const size_t output_file_size = this->output_file_size();
|
|
const unsigned char* iv = of->get_input_view(0, output_file_size);
|
|
const char* style = parameters->options().build_id();
|
|
|
|
// If we get here with style == "tree" then the output must be
|
|
// too small for chunking, and we use SHA-1 in that case.
|
|
if ((strcmp(style, "sha1") == 0) || (strcmp(style, "tree") == 0))
|
|
sha1_buffer(reinterpret_cast<const char*>(iv), output_file_size, ov);
|
|
else if (strcmp(style, "md5") == 0)
|
|
md5_buffer(reinterpret_cast<const char*>(iv), output_file_size, ov);
|
|
else
|
|
gold_unreachable();
|
|
|
|
of->free_input_view(0, output_file_size, iv);
|
|
}
|
|
else
|
|
{
|
|
// Non-overlapping substrings of the output file have been hashed.
|
|
// Compute SHA-1 hash of the hashes.
|
|
sha1_buffer(reinterpret_cast<const char*>(array_of_hashes),
|
|
size_of_hashes, ov);
|
|
delete[] array_of_hashes;
|
|
}
|
|
|
|
of->write_output_view(this->build_id_note_->offset(),
|
|
this->build_id_note_->data_size(),
|
|
ov);
|
|
}
|
|
|
|
// Write out a binary file. This is called after the link is
|
|
// complete. IN is the temporary output file we used to generate the
|
|
// ELF code. We simply walk through the segments, read them from
|
|
// their file offset in IN, and write them to their load address in
|
|
// the output file. FIXME: with a bit more work, we could support
|
|
// S-records and/or Intel hex format here.
|
|
|
|
void
|
|
Layout::write_binary(Output_file* in) const
|
|
{
|
|
gold_assert(parameters->options().oformat_enum()
|
|
== General_options::OBJECT_FORMAT_BINARY);
|
|
|
|
// Get the size of the binary file.
|
|
uint64_t max_load_address = 0;
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD && (*p)->filesz() > 0)
|
|
{
|
|
uint64_t max_paddr = (*p)->paddr() + (*p)->filesz();
|
|
if (max_paddr > max_load_address)
|
|
max_load_address = max_paddr;
|
|
}
|
|
}
|
|
|
|
Output_file out(parameters->options().output_file_name());
|
|
out.open(max_load_address);
|
|
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
{
|
|
if ((*p)->type() == elfcpp::PT_LOAD && (*p)->filesz() > 0)
|
|
{
|
|
const unsigned char* vin = in->get_input_view((*p)->offset(),
|
|
(*p)->filesz());
|
|
unsigned char* vout = out.get_output_view((*p)->paddr(),
|
|
(*p)->filesz());
|
|
memcpy(vout, vin, (*p)->filesz());
|
|
out.write_output_view((*p)->paddr(), (*p)->filesz(), vout);
|
|
in->free_input_view((*p)->offset(), (*p)->filesz(), vin);
|
|
}
|
|
}
|
|
|
|
out.close();
|
|
}
|
|
|
|
// Print the output sections to the map file.
|
|
|
|
void
|
|
Layout::print_to_mapfile(Mapfile* mapfile) const
|
|
{
|
|
for (Segment_list::const_iterator p = this->segment_list_.begin();
|
|
p != this->segment_list_.end();
|
|
++p)
|
|
(*p)->print_sections_to_mapfile(mapfile);
|
|
for (Section_list::const_iterator p = this->unattached_section_list_.begin();
|
|
p != this->unattached_section_list_.end();
|
|
++p)
|
|
(*p)->print_to_mapfile(mapfile);
|
|
}
|
|
|
|
// Print statistical information to stderr. This is used for --stats.
|
|
|
|
void
|
|
Layout::print_stats() const
|
|
{
|
|
this->namepool_.print_stats("section name pool");
|
|
this->sympool_.print_stats("output symbol name pool");
|
|
this->dynpool_.print_stats("dynamic name pool");
|
|
|
|
for (Section_list::const_iterator p = this->section_list_.begin();
|
|
p != this->section_list_.end();
|
|
++p)
|
|
(*p)->print_merge_stats();
|
|
}
|
|
|
|
// Write_sections_task methods.
|
|
|
|
// We can always run this task.
|
|
|
|
Task_token*
|
|
Write_sections_task::is_runnable()
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
// We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
|
|
// when finished.
|
|
|
|
void
|
|
Write_sections_task::locks(Task_locker* tl)
|
|
{
|
|
tl->add(this, this->output_sections_blocker_);
|
|
if (this->input_sections_blocker_ != NULL)
|
|
tl->add(this, this->input_sections_blocker_);
|
|
tl->add(this, this->final_blocker_);
|
|
}
|
|
|
|
// Run the task--write out the data.
|
|
|
|
void
|
|
Write_sections_task::run(Workqueue*)
|
|
{
|
|
this->layout_->write_output_sections(this->of_);
|
|
}
|
|
|
|
// Write_data_task methods.
|
|
|
|
// We can always run this task.
|
|
|
|
Task_token*
|
|
Write_data_task::is_runnable()
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
// We need to unlock FINAL_BLOCKER when finished.
|
|
|
|
void
|
|
Write_data_task::locks(Task_locker* tl)
|
|
{
|
|
tl->add(this, this->final_blocker_);
|
|
}
|
|
|
|
// Run the task--write out the data.
|
|
|
|
void
|
|
Write_data_task::run(Workqueue*)
|
|
{
|
|
this->layout_->write_data(this->symtab_, this->of_);
|
|
}
|
|
|
|
// Write_symbols_task methods.
|
|
|
|
// We can always run this task.
|
|
|
|
Task_token*
|
|
Write_symbols_task::is_runnable()
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
// We need to unlock FINAL_BLOCKER when finished.
|
|
|
|
void
|
|
Write_symbols_task::locks(Task_locker* tl)
|
|
{
|
|
tl->add(this, this->final_blocker_);
|
|
}
|
|
|
|
// Run the task--write out the symbols.
|
|
|
|
void
|
|
Write_symbols_task::run(Workqueue*)
|
|
{
|
|
this->symtab_->write_globals(this->sympool_, this->dynpool_,
|
|
this->layout_->symtab_xindex(),
|
|
this->layout_->dynsym_xindex(), this->of_);
|
|
}
|
|
|
|
// Write_after_input_sections_task methods.
|
|
|
|
// We can only run this task after the input sections have completed.
|
|
|
|
Task_token*
|
|
Write_after_input_sections_task::is_runnable()
|
|
{
|
|
if (this->input_sections_blocker_->is_blocked())
|
|
return this->input_sections_blocker_;
|
|
return NULL;
|
|
}
|
|
|
|
// We need to unlock FINAL_BLOCKER when finished.
|
|
|
|
void
|
|
Write_after_input_sections_task::locks(Task_locker* tl)
|
|
{
|
|
tl->add(this, this->final_blocker_);
|
|
}
|
|
|
|
// Run the task.
|
|
|
|
void
|
|
Write_after_input_sections_task::run(Workqueue*)
|
|
{
|
|
this->layout_->write_sections_after_input_sections(this->of_);
|
|
}
|
|
|
|
// Build IDs can be computed as a "flat" sha1 or md5 of a string of bytes,
|
|
// or as a "tree" where each chunk of the string is hashed and then those
|
|
// hashes are put into a (much smaller) string which is hashed with sha1.
|
|
// We compute a checksum over the entire file because that is simplest.
|
|
|
|
void
|
|
Build_id_task_runner::run(Workqueue* workqueue, const Task*)
|
|
{
|
|
Task_token* post_hash_tasks_blocker = new Task_token(true);
|
|
const Layout* layout = this->layout_;
|
|
Output_file* of = this->of_;
|
|
const size_t filesize = (layout->output_file_size() <= 0 ? 0
|
|
: static_cast<size_t>(layout->output_file_size()));
|
|
unsigned char* array_of_hashes = NULL;
|
|
size_t size_of_hashes = 0;
|
|
|
|
if (strcmp(this->options_->build_id(), "tree") == 0
|
|
&& this->options_->build_id_chunk_size_for_treehash() > 0
|
|
&& filesize > 0
|
|
&& (filesize >= this->options_->build_id_min_file_size_for_treehash()))
|
|
{
|
|
static const size_t MD5_OUTPUT_SIZE_IN_BYTES = 16;
|
|
const size_t chunk_size =
|
|
this->options_->build_id_chunk_size_for_treehash();
|
|
const size_t num_hashes = ((filesize - 1) / chunk_size) + 1;
|
|
post_hash_tasks_blocker->add_blockers(num_hashes);
|
|
size_of_hashes = num_hashes * MD5_OUTPUT_SIZE_IN_BYTES;
|
|
array_of_hashes = new unsigned char[size_of_hashes];
|
|
unsigned char *dst = array_of_hashes;
|
|
for (size_t i = 0, src_offset = 0; i < num_hashes;
|
|
i++, dst += MD5_OUTPUT_SIZE_IN_BYTES, src_offset += chunk_size)
|
|
{
|
|
size_t size = std::min(chunk_size, filesize - src_offset);
|
|
workqueue->queue(new Hash_task(of,
|
|
src_offset,
|
|
size,
|
|
dst,
|
|
post_hash_tasks_blocker));
|
|
}
|
|
}
|
|
|
|
// Queue the final task to write the build id and close the output file.
|
|
workqueue->queue(new Task_function(new Close_task_runner(this->options_,
|
|
layout,
|
|
of,
|
|
array_of_hashes,
|
|
size_of_hashes),
|
|
post_hash_tasks_blocker,
|
|
"Task_function Close_task_runner"));
|
|
}
|
|
|
|
// Close_task_runner methods.
|
|
|
|
// Finish up the build ID computation, if necessary, and write a binary file,
|
|
// if necessary. Then close the output file.
|
|
|
|
void
|
|
Close_task_runner::run(Workqueue*, const Task*)
|
|
{
|
|
// At this point the multi-threaded part of the build ID computation,
|
|
// if any, is done. See Build_id_task_runner.
|
|
this->layout_->write_build_id(this->of_, this->array_of_hashes_,
|
|
this->size_of_hashes_);
|
|
|
|
// If we've been asked to create a binary file, we do so here.
|
|
if (this->options_->oformat_enum() != General_options::OBJECT_FORMAT_ELF)
|
|
this->layout_->write_binary(this->of_);
|
|
|
|
if (this->options_->dependency_file())
|
|
File_read::write_dependency_file(this->options_->dependency_file(),
|
|
this->options_->output_file_name());
|
|
|
|
this->of_->close();
|
|
}
|
|
|
|
// Instantiate the templates we need. We could use the configure
|
|
// script to restrict this to only the ones for implemented targets.
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::init_fixed_output_section<32, false>(
|
|
const char* name,
|
|
elfcpp::Shdr<32, false>& shdr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
Output_section*
|
|
Layout::init_fixed_output_section<32, true>(
|
|
const char* name,
|
|
elfcpp::Shdr<32, true>& shdr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::init_fixed_output_section<64, false>(
|
|
const char* name,
|
|
elfcpp::Shdr<64, false>& shdr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
Output_section*
|
|
Layout::init_fixed_output_section<64, true>(
|
|
const char* name,
|
|
elfcpp::Shdr<64, true>& shdr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout<32, false>(Sized_relobj_file<32, false>* object,
|
|
unsigned int shndx,
|
|
const char* name,
|
|
const elfcpp::Shdr<32, false>& shdr,
|
|
unsigned int, unsigned int, unsigned int, off_t*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout<32, true>(Sized_relobj_file<32, true>* object,
|
|
unsigned int shndx,
|
|
const char* name,
|
|
const elfcpp::Shdr<32, true>& shdr,
|
|
unsigned int, unsigned int, unsigned int, off_t*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout<64, false>(Sized_relobj_file<64, false>* object,
|
|
unsigned int shndx,
|
|
const char* name,
|
|
const elfcpp::Shdr<64, false>& shdr,
|
|
unsigned int, unsigned int, unsigned int, off_t*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout<64, true>(Sized_relobj_file<64, true>* object,
|
|
unsigned int shndx,
|
|
const char* name,
|
|
const elfcpp::Shdr<64, true>& shdr,
|
|
unsigned int, unsigned int, unsigned int, off_t*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout_reloc<32, false>(Sized_relobj_file<32, false>* object,
|
|
unsigned int reloc_shndx,
|
|
const elfcpp::Shdr<32, false>& shdr,
|
|
Output_section* data_section,
|
|
Relocatable_relocs* rr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout_reloc<32, true>(Sized_relobj_file<32, true>* object,
|
|
unsigned int reloc_shndx,
|
|
const elfcpp::Shdr<32, true>& shdr,
|
|
Output_section* data_section,
|
|
Relocatable_relocs* rr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout_reloc<64, false>(Sized_relobj_file<64, false>* object,
|
|
unsigned int reloc_shndx,
|
|
const elfcpp::Shdr<64, false>& shdr,
|
|
Output_section* data_section,
|
|
Relocatable_relocs* rr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout_reloc<64, true>(Sized_relobj_file<64, true>* object,
|
|
unsigned int reloc_shndx,
|
|
const elfcpp::Shdr<64, true>& shdr,
|
|
Output_section* data_section,
|
|
Relocatable_relocs* rr);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Layout::layout_group<32, false>(Symbol_table* symtab,
|
|
Sized_relobj_file<32, false>* object,
|
|
unsigned int,
|
|
const char* group_section_name,
|
|
const char* signature,
|
|
const elfcpp::Shdr<32, false>& shdr,
|
|
elfcpp::Elf_Word flags,
|
|
std::vector<unsigned int>* shndxes);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Layout::layout_group<32, true>(Symbol_table* symtab,
|
|
Sized_relobj_file<32, true>* object,
|
|
unsigned int,
|
|
const char* group_section_name,
|
|
const char* signature,
|
|
const elfcpp::Shdr<32, true>& shdr,
|
|
elfcpp::Elf_Word flags,
|
|
std::vector<unsigned int>* shndxes);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Layout::layout_group<64, false>(Symbol_table* symtab,
|
|
Sized_relobj_file<64, false>* object,
|
|
unsigned int,
|
|
const char* group_section_name,
|
|
const char* signature,
|
|
const elfcpp::Shdr<64, false>& shdr,
|
|
elfcpp::Elf_Word flags,
|
|
std::vector<unsigned int>* shndxes);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Layout::layout_group<64, true>(Symbol_table* symtab,
|
|
Sized_relobj_file<64, true>* object,
|
|
unsigned int,
|
|
const char* group_section_name,
|
|
const char* signature,
|
|
const elfcpp::Shdr<64, true>& shdr,
|
|
elfcpp::Elf_Word flags,
|
|
std::vector<unsigned int>* shndxes);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout_eh_frame<32, false>(Sized_relobj_file<32, false>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
const unsigned char* symbol_names,
|
|
off_t symbol_names_size,
|
|
unsigned int shndx,
|
|
const elfcpp::Shdr<32, false>& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type,
|
|
off_t* off);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout_eh_frame<32, true>(Sized_relobj_file<32, true>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
const unsigned char* symbol_names,
|
|
off_t symbol_names_size,
|
|
unsigned int shndx,
|
|
const elfcpp::Shdr<32, true>& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type,
|
|
off_t* off);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
Output_section*
|
|
Layout::layout_eh_frame<64, false>(Sized_relobj_file<64, false>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
const unsigned char* symbol_names,
|
|
off_t symbol_names_size,
|
|
unsigned int shndx,
|
|
const elfcpp::Shdr<64, false>& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type,
|
|
off_t* off);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
Output_section*
|
|
Layout::layout_eh_frame<64, true>(Sized_relobj_file<64, true>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
const unsigned char* symbol_names,
|
|
off_t symbol_names_size,
|
|
unsigned int shndx,
|
|
const elfcpp::Shdr<64, true>& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type,
|
|
off_t* off);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Layout::add_to_gdb_index(bool is_type_unit,
|
|
Sized_relobj<32, false>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
unsigned int shndx,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Layout::add_to_gdb_index(bool is_type_unit,
|
|
Sized_relobj<32, true>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
unsigned int shndx,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Layout::add_to_gdb_index(bool is_type_unit,
|
|
Sized_relobj<64, false>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
unsigned int shndx,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Layout::add_to_gdb_index(bool is_type_unit,
|
|
Sized_relobj<64, true>* object,
|
|
const unsigned char* symbols,
|
|
off_t symbols_size,
|
|
unsigned int shndx,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type);
|
|
#endif
|
|
|
|
} // End namespace gold.
|