nodeConstAnalysis.h

#ifndef NODE_CONST_ANALYSIS_H
#define NODE_CONST_ANALYSIS_H

#include "genericDataflowCommon.h"
#include "genUID.h"
#include "VirtualCFGIterator.h"
#include "cfgUtils.h"
#include "CallGraphTraverse.h"
#include "analysisCommon.h"
#include "analysis.h"
#include "dataflow.h"
#include "latticeFull.h"
#include "printAnalysisStates.h"

#include <string>
#include <vector>

extern int nodeConstAnalysisDebugLevel;

// For each live variable records whether this variable has not been assigned, has one value or multiple values.
// There is one nodeConstAnalysisDebugLevel object for every variable
class nodeConstLattice : public FiniteLattice
{
        private:
        // the unique ID of the value of the variable (if known)
        unsigned long valID;
                
        public:
        // The different levels of this lattice
        // this object is uninitialized
        static const int uninitialized=0; 
        
        private:
        // no information is known about the value of the variable
        // (we haven't seen an assignment)
        static const int bottom=1; 
        // the value of the variable is known
        // (we've seen exactly one assignment)
        static const int valKnown=2; 
        // this variable may have more than one value at the given CFGNode
        static const int top=3; 
        
        public:
        // public names for the different levels that correspond to the final outcome of the analysis
        static const int noAssign=bottom;
        static const int constVal=valKnown;
        static const int multVal=top;
        
        private:
        // this object's current level in the lattice: (uninitialized, bottom, valKnown, top)
        short level;
        
        public:
        
        nodeConstLattice()
        {
                valID=0;
                level=uninitialized;
        }
        
        nodeConstLattice(const nodeConstLattice& that)
        {
                this->valID = that.valID;
                this->level = that.level;
        }
        
        // initializes this Lattice to its default state, if it is not already initialized
        void initialize()
        {
                if(level == uninitialized)
                {
                        valID=0;
                        level=bottom;
                }
        }
        
        // returns a copy of this lattice
        Lattice* copy() const;
        
        // overwrites the state of this Lattice with that of that Lattice
        void copy(Lattice* that);
        
        // computes the meet of this and that and saves the result in this
        // returns true if this causes this to change and false otherwise
        bool meetUpdate(Lattice* that);
        
        // Computes the maximum of this node and that, which is just like meet
        // except that different values get max-ed, rather than push the result to top
        // returns true if this causes this to change and false otherwise
        bool maxUpdate(nodeConstLattice& that);
        
        // If this lattice is at level valKnown, increments the value by the given amount
        // returns true if this causes this to change and false otherwise
        bool increment(int val=1);
        
        // computes the meet of this and that and returns the result
        //Lattice* meet(Lattice* that) const;
        
        bool operator==(Lattice* that);
        
        /*private:
        // returns this object's level
        short getLevel() const;
        
        public:*/
        // returns whether the variable is constant at the current node
        short getValConst() const;
        
        // Sets the state of this lattice to bottom
        // returns true if this causes the lattice's state to change, false otherwise
        bool setToBottom();
        
        // Sets the state of this lattice to the given value.
        // returns true if this causes the lattice's state to change, false otherwise
        bool set(unsigned long valID);
        
        // Sets the state of this lattice to top
        // returns true if this causes the lattice's state to change, false otherwise
        bool setToTop();
                
        std::string str(std::string indent="");
};

class nodeConstAnalysis : public IntraFWDataflow
{
        protected:
        genUID uids;
        
        public:
        nodeConstAnalysis(): IntraFWDataflow()
        {       }
        
        /*// generates the initial variable-specific lattice state for a dataflow node
        Lattice* genInitVarState(const Function& func, const DataflowNode& n, const NodeState& state);  
        
        // generates the initial non-variable-specific lattice state for a dataflow node
        Lattice* genInitNonVarState(const Function& func, const DataflowNode& n, const NodeState& state);*/
        
        // generates the initial lattice state for the given dataflow node, in the given function, with the given NodeState
        //std::vector<Lattice*> genInitState(const Function& func, const DataflowNode& n, const NodeState& state);
        void genInitState(const Function& func, const DataflowNode& n, const NodeState& state,
                          std::vector<Lattice*>& initLattices, std::vector<NodeFact*>& initFacts);
                
        bool transfer(const Function& func, const DataflowNode& n, NodeState& state, const std::vector<Lattice*>& dfInfo);
};

// runs the nodeConstAnalysis on the project and returns the resulting nodeConstAnalysis object
nodeConstAnalysis* runNodeConstAnalysis();

// prints the Lattices set by the given nodeConstAnalysis 
void printNodeConstAnalysisStates(nodeConstAnalysis* da, std::string indent="");

#endif