From 0f3b89d87a62ea42186fb5ba525dadde36182a97 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Mon, 24 Jan 2011 21:48:40 +0000 Subject: * plugin.cc (class Plugin_rescan): Define new class. (Plugin_manager::claim_file): Set any_claimed_. (Plugin_manager::save_archive): New function. (Plugin_manager::save_input_group): New function. (Plugin_manager::all_symbols_read): Create Plugin_rescan task if necessary. (Plugin_manager::new_undefined_symbol): New function. (Plugin_manager::rescan): New function. (Plugin_manager::rescannable_defines): New function. (Plugin_manager::add_input_file): Set any_added_. * plugin.h (class Plugin_manager): define new fields rescannable_, undefined_symbols_, any_claimed_, and any_added_. Declare Plugin_rescan as friend. Declare new functions. (Plugin_manager::Rescannable): Define type. (Plugin_manager::Rescannable_list): Define type. (Plugin_manager::Undefined_symbol_list): Define type. (Plugin_manager::Plugin_manager): Initialize new fields. * archive.cc (Archive::defines_symbol): New function. (Add_archive_symbols::run): Pass archive to plugins if any. * archive.h (class Archive): Declare defines_symbol. * readsyms.cc (Input_group::~Input_group): New function. (Finish_group::run): Pass input_group to plugins if any. * readsyms.h (class Input_group): Declare destructor. * symtab.cc (add_from_object): Pass undefined symbol to plugins if any. --- gold/plugin.cc | 206 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 205 insertions(+), 1 deletion(-) (limited to 'gold/plugin.cc') diff --git a/gold/plugin.cc b/gold/plugin.cc index a3569c9..9c444c2 100644 --- a/gold/plugin.cc +++ b/gold/plugin.cc @@ -1,6 +1,6 @@ // plugin.cc -- plugin manager for gold -*- C++ -*- -// Copyright 2008, 2009, 2010 Free Software Foundation, Inc. +// Copyright 2008, 2009, 2010, 2011 Free Software Foundation, Inc. // Written by Cary Coutant . // This file is part of gold. @@ -261,6 +261,45 @@ Plugin::cleanup() } } +// This task is used to rescan archives as needed. + +class Plugin_rescan : public Task +{ + public: + Plugin_rescan(Task_token* this_blocker, Task_token* next_blocker) + : this_blocker_(this_blocker), next_blocker_(next_blocker) + { } + + ~Plugin_rescan() + { + delete this->this_blocker_; + } + + Task_token* + is_runnable() + { + if (this->this_blocker_->is_blocked()) + return this->this_blocker_; + return NULL; + } + + void + locks(Task_locker* tl) + { tl->add(this, this->next_blocker_); } + + void + run(Workqueue*) + { parameters->options().plugins()->rescan(this); } + + std::string + get_name() const + { return "Plugin_rescan"; } + + private: + Task_token* this_blocker_; + Task_token* next_blocker_; +}; + // Plugin_manager methods. Plugin_manager::~Plugin_manager() @@ -311,6 +350,8 @@ Plugin_manager::claim_file(Input_file* input_file, off_t offset, { if ((*this->current_)->claim_file(&this->plugin_input_file_)) { + this->any_claimed_ = true; + if (this->objects_.size() > handle) return this->objects_[handle]; @@ -324,6 +365,31 @@ Plugin_manager::claim_file(Input_file* input_file, off_t offset, return NULL; } +// Save an archive. This is used so that a plugin can add a file +// which refers to a symbol which was not previously referenced. In +// that case we want to pretend that the symbol was referenced before, +// and pull in the archive object. + +void +Plugin_manager::save_archive(Archive* archive) +{ + if (this->in_replacement_phase_ || !this->any_claimed_) + delete archive; + else + this->rescannable_.push_back(Rescannable(archive)); +} + +// Save an Input_group. This is like save_archive. + +void +Plugin_manager::save_input_group(Input_group* input_group) +{ + if (this->in_replacement_phase_ || !this->any_claimed_) + delete input_group; + else + this->rescannable_.push_back(Rescannable(input_group)); +} + // Call the all-symbols-read handlers. void @@ -348,9 +414,146 @@ Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task, ++this->current_) (*this->current_)->all_symbols_read(); + if (this->any_added_) + { + Task_token* next_blocker = new Task_token(true); + next_blocker->add_blocker(); + workqueue->queue(new Plugin_rescan(this->this_blocker_, next_blocker)); + this->this_blocker_ = next_blocker; + } + *last_blocker = this->this_blocker_; } +// This is called when we see a new undefined symbol. If we are in +// the replacement phase, this means that we may need to rescan some +// archives we have previously seen. + +void +Plugin_manager::new_undefined_symbol(Symbol* sym) +{ + if (this->in_replacement_phase_) + this->undefined_symbols_.push_back(sym); +} + +// Rescan archives as needed. This handles the case where a new +// object file added by a plugin has an undefined reference to some +// symbol defined in an archive. + +void +Plugin_manager::rescan(Task* task) +{ + size_t rescan_pos = 0; + size_t rescan_size = this->rescannable_.size(); + while (!this->undefined_symbols_.empty()) + { + if (rescan_pos >= rescan_size) + { + this->undefined_symbols_.clear(); + return; + } + + Undefined_symbol_list undefs; + undefs.reserve(this->undefined_symbols_.size()); + this->undefined_symbols_.swap(undefs); + + size_t min_rescan_pos = rescan_size; + + for (Undefined_symbol_list::const_iterator p = undefs.begin(); + p != undefs.end(); + ++p) + { + if (!(*p)->is_undefined()) + continue; + + this->undefined_symbols_.push_back(*p); + + // Find the first rescan archive which defines this symbol, + // starting at the current rescan position. The rescan position + // exists so that given -la -lb -lc we don't look for undefined + // symbols in -lb back in -la, but instead get the definition + // from -lc. Don't bother to look past the current minimum + // rescan position. + for (size_t i = rescan_pos; i < min_rescan_pos; ++i) + { + if (this->rescannable_defines(i, *p)) + { + min_rescan_pos = i; + break; + } + } + } + + if (min_rescan_pos >= rescan_size) + { + // We didn't find any rescannable archives which define any + // undefined symbols. + return; + } + + const Rescannable& r(this->rescannable_[min_rescan_pos]); + if (r.is_archive) + { + Task_lock_obj tl(task, r.u.archive); + r.u.archive->add_symbols(this->symtab_, this->layout_, + this->input_objects_, this->mapfile_); + } + else + { + size_t next_saw_undefined = this->symtab_->saw_undefined(); + size_t saw_undefined; + do + { + saw_undefined = next_saw_undefined; + + for (Input_group::const_iterator p = r.u.input_group->begin(); + p != r.u.input_group->end(); + ++p) + { + Task_lock_obj tl(task, *p); + + (*p)->add_symbols(this->symtab_, this->layout_, + this->input_objects_, this->mapfile_); + } + + next_saw_undefined = this->symtab_->saw_undefined(); + } + while (saw_undefined != next_saw_undefined); + } + + for (size_t i = rescan_pos; i < min_rescan_pos + 1; ++i) + { + if (this->rescannable_[i].is_archive) + delete this->rescannable_[i].u.archive; + else + delete this->rescannable_[i].u.input_group; + } + + rescan_pos = min_rescan_pos + 1; + } +} + +// Return whether the rescannable at index I defines SYM. + +bool +Plugin_manager::rescannable_defines(size_t i, Symbol* sym) +{ + const Rescannable& r(this->rescannable_[i]); + if (r.is_archive) + return r.u.archive->defines_symbol(sym); + else + { + for (Input_group::const_iterator p = r.u.input_group->begin(); + p != r.u.input_group->end(); + ++p) + { + if ((*p)->defines_symbol(sym)) + return true; + } + return false; + } +} + // Layout deferred objects. void @@ -473,6 +676,7 @@ Plugin_manager::add_input_file(const char* pathname, bool is_lib) this->this_blocker_, next_blocker)); this->this_blocker_ = next_blocker; + this->any_added_ = true; return LDPS_OK; } -- cgit v1.1