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/* ScummVM Tools
*
* ScummVM Tools is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef ENGINE_H
#define ENGINE_H
#include "disassembler.h"
#include "codegen.h"
#include <set>
#include <string>
#include <vector>
/**
* Structure representing a function.
*/
struct Function {
public:
ConstInstIterator _startIt; ///< Iterator to of the first instruction in the function, if available.
ConstInstIterator _endIt; ///< Iterator to the instruction immediately after the function, similar to end() on STL containers. If _endIt == _startIt, the function endpoint is assumed to be unknown.
std::string _name; ///< Function name.
GraphVertex _v; ///< Graph vertex for the entry point to the function.
uint32 _args; ///< Number of arguments to the function.
bool _retVal; ///< Whether or not the function returns a value.
std::string _metadata; ///< Metadata for code generation.
/**
* Parameterless constructor for Function. Required for use with STL, should not be called manually.
*/
Function() {
}
/**
* Constructor for Function.
*
* @param startIt Index of the first instruction in the function.
* @param endIt Index of the instruction immediately after the function, similar to end() on STL containers.
*/
Function(ConstInstIterator startIt, ConstInstIterator endIt) : _startIt(startIt), _endIt(endIt) {
}
};
/**
* Type representing a map of functions, indexed by starting address.
*/
typedef std::map<uint32, Function> FuncMap;
/**
* Base class for engines.
*/
class Engine {
public:
virtual ~Engine() {}
/**
* Retrieve the disassembler for the engine.
*
* @param insts Reference to the std::vector to place the Instructions in.
* @return Pointer to a Disassembler for the engine.
*/
virtual Disassembler *getDisassembler(InstVec &insts) = 0;
/**
* Retrieve the code generator for the engine.
*
* @param output The std::ostream to output the code to.
* @return Pointer to a CodeGenerator for the engine.
*/
virtual CodeGenerator *getCodeGenerator(std::ostream &output) = 0;
/**
* Post-processing step after CFG analysis.
* @param insts Reference to the std::vector to place the Instructions in.
* @param g Graph generated from the CFG analysis.
*/
virtual void postCFG(InstVec &insts, Graph g) { }
/**
* Whether or not code flow analysis is supported for this engine.
*
* @return True if supported, false if not. If false is returned, code flow analysis should not take place, and -D should be implied.
*/
virtual bool supportsCodeFlow() const { return true; }
/**
* Whether or not code generation is supported for this engine.
*
* @return True if supported, false if not. If false is returned, code generation should not take place, and -G should be implied.
*/
virtual bool supportsCodeGen() const { return true; }
/**
* Whether or not additional functions should be looked for during CFG analysis.
* Code that was normally unreachable will be treated as starting a new function.
* Note: You will need a post-processing step to add the necessary metadata to the functions.
*
* @return True if yes, false if no.
*/
virtual bool detectMoreFuncs() const { return false; }
FuncMap _functions; ///< Map to functions in the current script, indexed by starting address.
/**
* Fill a vector with the names of all variants supported for this engine.
* If variants are not used by this engine, leave the vector empty (default implementation).
*
* @param variants Vector to add the supported variants to.
*/
virtual void getVariants(std::vector<std::string> &variants) const { };
std::string _variant; ///< Engine variant to use for the script.
/**
* Whether or not to use "pure" grouping during code flow analysis.
* With pure grouping, code flow analysis only looks at branches when merging.
* This method may be more appropriate for non-stack-based engines.
*
* @return True if pure grouping should be used, false if not.
*/
virtual bool usePureGrouping() const { return false; }
};
#endif