Resolver.h   [plain text]

/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-*
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 * Copyright (c) 2009 Apple Inc. All rights reserved.
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 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 *
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 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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#ifndef __RESOLVER_H__
#define __RESOLVER_H__

#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/sysctl.h>
#include <fcntl.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <mach/mach_time.h>
#include <mach/vm_statistics.h>
#include <mach/mach_init.h>
#include <mach/mach_host.h>
#include <dlfcn.h>
#include <mach-o/dyld.h>

#include <vector>

#include "Options.h"
#include "ld.hpp"
#include "SymbolTable.h"


namespace ld {
namespace tool {




class Resolver : public ld::File::AtomHandler
{
public:
							Resolver(const Options& opts, const InputFiles& inputs, ld::Internal& state) 
								: _options(opts), _inputFiles(inputs), _internal(state), 
								  _symbolTable(opts, state.indirectBindingTable),
								  _haveLLVMObjs(false), _addToFinalSection(false),
								  _completedInitialObjectFiles(false) {}
								

		virtual void		doAtom(const ld::Atom&);
		virtual void		doFile(const class File&);
		
		void				resolve();

	
private:
	struct WhyLiveBackChain
	{
		WhyLiveBackChain*	previous;
		const ld::Atom*		referer;
	};

	void					initializeState();
	void					buildAtomList();
	void					addInitialUndefines();
	void					deadStripOptimize();
	void					resolveUndefines();
	void					checkUndefines(bool force=false);
	void					checkDylibSymbolCollisions();
	void					tentativeOverrideOfDylib(ld::Atom&);
	void					fillInInternalState();
	void					fillInHelpersInInternalState();
	void					removeCoalescedAwayAtoms();
	void					linkTimeOptimize();
	void					convertReferencesToIndirect(const ld::Atom& atom);
	const ld::Atom*			entryPoint(bool searchArchives);
	void					markLive(const ld::Atom& atom, WhyLiveBackChain* previous);
	bool					isDtraceProbe(ld::Fixup::Kind kind);
	void					liveUndefines(std::vector<const char*>&);
	bool					printReferencedBy(const char* name, SymbolTable::IndirectBindingSlot slot);
			

	class CStringEquals {
	public:
		bool operator()(const char* left, const char* right) const { return (strcmp(left, right) == 0); }
	};
	typedef __gnu_cxx::hash_set<const char*, __gnu_cxx::hash<const char*>, CStringEquals>  StringSet;

	class NotLive {
	public:
		bool operator()(const ld::Atom* atom) const {
			return ! (atom->live() || atom->dontDeadStrip());
		}
	};

	class AtomCoalescedAway {
	public:
		bool operator()(const ld::Atom* atom) const {
			return atom->coalescedAway();
		}
	};

	const Options&					_options;
	const InputFiles&				_inputFiles;
	ld::Internal&					_internal;
	std::vector<const ld::Atom*>	_atoms;
	std::set<const ld::Atom*>		_deadStripRoots;
	std::vector<const ld::Atom*>	_atomsWithUnresolvedReferences;
	SymbolTable						_symbolTable;
	bool							_haveLLVMObjs;
	bool							_addToFinalSection;
	bool							_completedInitialObjectFiles;
};


class DeadStripResolver   
{
public:

	
private:

};

} // namespace tool 
} // namespace ld 



#endif // __RESOLVER_H__