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path: root/lib/Expr/ExprSMTLIBPrinter.cpp
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//===-- ExprSMTLIBPrinter.cpp ------------------------------------------*- C++ -*-===//
//
//                     The KLEE Symbolic Virtual Machine
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include <iostream>

#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "klee/util/ExprSMTLIBPrinter.h"

using namespace std;

namespace ExprSMTLIBOptions
{
	//Command line options
	llvm::cl::opt<klee::ExprSMTLIBPrinter::ConstantDisplayMode> argConstantDisplayMode
	("smtlib-display-constants", llvm::cl::desc("Sets how bitvector constants are written in generated SMT-LIBv2 files (default=dec)"),
	llvm::cl::values( clEnumValN(klee::ExprSMTLIBPrinter::BINARY, "bin","Use binary form (e.g. #b00101101)"),
					  clEnumValN(klee::ExprSMTLIBPrinter::HEX, "hex","Use Hexadecimal form (e.g. #x2D)"),
					  clEnumValN(klee::ExprSMTLIBPrinter::DECIMAL, "dec","Use decimal form (e.g. (_ bv45 8) )"),
					  clEnumValEnd
					),
					llvm::cl::init(klee::ExprSMTLIBPrinter::DECIMAL)


	);

	llvm::cl::opt<bool> humanReadableSMTLIB("smtlib-human-readable",
				llvm::cl::desc("Enables generated SMT-LIBv2 files to be human readable (default=off)"),
				llvm::cl::init(false)


	);

}


namespace klee
{

	ExprSMTLIBPrinter::ExprSMTLIBPrinter() :
		usedArrays(), o(NULL), query(NULL), p(NULL), haveConstantArray(false), logicToUse(QF_AUFBV),
		humanReadable(ExprSMTLIBOptions::humanReadableSMTLIB), smtlibBoolOptions(), arraysToCallGetValueOn(NULL)
	{
		setConstantDisplayMode(ExprSMTLIBOptions::argConstantDisplayMode);
	}

	ExprSMTLIBPrinter::~ExprSMTLIBPrinter()
	{
		if(p!=NULL)
			delete p;
	}

	void ExprSMTLIBPrinter::setOutput(std::ostream& output)
	{
		o = &output;
		if(p!=NULL)
			delete p;

		p = new PrintContext(output);
	}

	void ExprSMTLIBPrinter::setQuery(const Query& q)
	{
		query = &q;
		reset(); // clear the data structures
		scanAll();
		negateQueryExpression();
	}

	void ExprSMTLIBPrinter::reset()
	{
		usedArrays.clear();
		haveConstantArray=false;

		/* Clear the PRODUCE_MODELS option if it was automatically set.
		 * We need to do this because the next query might not need the
		 * (get-value) SMT-LIBv2 command.
		 */
		if(arraysToCallGetValueOn !=NULL)
			setSMTLIBboolOption(PRODUCE_MODELS,OPTION_DEFAULT);

		arraysToCallGetValueOn=NULL;


	}

	bool ExprSMTLIBPrinter::isHumanReadable()
	{
		return humanReadable;
	}

	bool ExprSMTLIBPrinter::setConstantDisplayMode(ConstantDisplayMode cdm)
	{
		if(cdm > DECIMAL)
			return false;

		this->cdm = cdm;
		return true;
	}

	void ExprSMTLIBPrinter::printConstant(const ref<ConstantExpr>& e)
	{
		/* Handle simple boolean constants */

		if(e->isTrue())
		{
			*p << "true";
			return;
		}

		if(e->isFalse())
		{
			*p << "false";
			return;
		}

		/* Handle bitvector constants */

		std::string value;

		/* SMTLIBv2 deduces the bit-width (should be 8-bits in our case)
		 * from the length of the string (e.g. zero is #b00000000). LLVM
		 * doesn't know about this so we need to pad the printed output
		 * with the appropriate number of zeros (zeroPad)
		 */
		unsigned int zeroPad=0;

		switch(cdm)
		{
			case BINARY:
				e->toString(value,2);
				*p << "#b";

				zeroPad = e->getWidth() - value.length();

				for(unsigned int count=0; count < zeroPad; count++)
					*p << "0";

				*p << value ;
				break;

			case HEX:
				e->toString(value,16);
				*p << "#x";

				zeroPad =  (e->getWidth() / 4) - value.length();
				for(unsigned int count=0; count < zeroPad; count++)
					*p << "0";

				*p << value ;
				break;

			case DECIMAL:
				e->toString(value,10);
				*p << "(_ bv" << value<< " " << e->getWidth() << ")";
				break;

			default:
				std::cerr << "ExprSMTLIBPrinter::printConstant() : Unexpected Constant display mode" << std::endl;
		}
	}

	void ExprSMTLIBPrinter::printExpression(const ref<Expr>& e, ExprSMTLIBPrinter::SMTLIB_SORT expectedSort)
	{
		//check if casting might be necessary
		if(getSort(e) != expectedSort)
		{
			printCastToSort(e,expectedSort);
			return;
		}


		switch(e->getKind())
		{
			case Expr::Constant:
				printConstant(cast<ConstantExpr>(e));
				return; //base case

			case Expr::NotOptimized:
				//skip to child
				printExpression(e->getKid(0),expectedSort);
				return;

			case Expr::Read:
				printReadExpr(cast<ReadExpr>(e));
				return;

			case Expr::Extract:
				printExtractExpr(cast<ExtractExpr>(e));
				return;

			case Expr::SExt:
			case Expr::ZExt:
				printCastExpr(cast<CastExpr>(e));
				return;

			case Expr::Ne:
				printNotEqualExpr(cast<NeExpr>(e));
				return;

			case Expr::Select:
				//the if-then-else expression.
				printSelectExpr(cast<SelectExpr>(e),expectedSort);
				return;

			case Expr::Eq:
				/* The "=" operator is special in that it can take any sort but we must
				 * enforce that both arguments are the same type. We do this a lazy way
				 * by enforcing the second argument is of the same type as the first.
				 */
				printSortArgsExpr(e,getSort(e->getKid(0)));

				return;

			case Expr::And:
			case Expr::Or:
			case Expr::Xor:
			case Expr::Not:
				/* These operators have a bitvector version and a bool version.
				 * For these operators only (e.g. wouldn't apply to bvult) if the expected sort the
				 * expression is T then that implies the arguments are also of type T.
				 */
				printLogicalOrBitVectorExpr(e,expectedSort);

				return;


			default:
				/* The remaining operators (Add,Sub...,Ult,Ule,..)
				 * Expect SORT_BITVECTOR arguments
				 */
				printSortArgsExpr(e,SORT_BITVECTOR);
				return;
		}
	}

	void ExprSMTLIBPrinter::printReadExpr(const ref<ReadExpr>& e)
	{
		*p << "(" << getSMTLIBKeyword(e) << " ";
		p->pushIndent();

		printSeperator();

		//print array with updates recursively
		printUpdatesAndArray(e->updates.head,e->updates.root);

		//print index
		printSeperator();
		printExpression(e->index,SORT_BITVECTOR);

		p->popIndent();
		printSeperator();
		*p << ")";
	}

	void ExprSMTLIBPrinter::printExtractExpr(const ref<ExtractExpr>& e)
	{
		unsigned int lowIndex= e->offset;
		unsigned int highIndex= lowIndex + e->width -1;

		*p << "((_ " << getSMTLIBKeyword(e) << " " << highIndex << "  " << lowIndex << ") ";

		p->pushIndent(); //add indent for recursive call
		printSeperator();

		//recurse
		printExpression(e->getKid(0),SORT_BITVECTOR);

		p->popIndent(); //pop indent added for the recursive call
		printSeperator();
		*p << ")";
	}

	void ExprSMTLIBPrinter::printCastExpr(const ref<CastExpr>& e)
	{
		/* sign_extend and zero_extend behave slightly unusually in SMTLIBv2
		 * instead of specifying of what bit-width we would like to extend to
		 * we specify how many bits to add to the child expression
		 *
		 * e.g
		 * ((_ sign_extend 64) (_ bv5 32))
		 *
		 * gives a (_ BitVec 96) instead of (_ BitVec 64)
		 *
		 * So we must work out how many bits we need to add.
		 *
		 * (e->width) is the desired number of bits
		 * (e->src->getWidth()) is the number of bits in the child
		 */
		unsigned int numExtraBits= (e->width) - (e->src->getWidth());

		*p << "((_ " << getSMTLIBKeyword(e) << " " <<
				numExtraBits << ") ";

		p->pushIndent(); //add indent for recursive call
		printSeperator();

		//recurse
		printExpression(e->src,SORT_BITVECTOR);

		p->popIndent(); //pop indent added for recursive call
		printSeperator();

		*p << ")";
	}

	void ExprSMTLIBPrinter::printNotEqualExpr(const ref<NeExpr>& e)
	{
		*p << "(not (";
		p->pushIndent();
		*p << "=" << " ";
		p->pushIndent();
		printSeperator();

		/* The "=" operators allows both sorts. We assume
		 * that the second argument sort should be forced to be the same sort as the
		 * first argument
		 */
		SMTLIB_SORT s = getSort(e->getKid(0));

		printExpression(e->getKid(0),s);
		printSeperator();
		printExpression(e->getKid(1),s);
		p->popIndent();
		printSeperator();

		*p << ")";
		p->popIndent();
		printSeperator();
		*p << ")";
	}


	const char* ExprSMTLIBPrinter::getSMTLIBKeyword(const ref<Expr>& e)
	{

		switch(e->getKind())
		{
			case Expr::Read: return "select";
			case Expr::Select: return "ite";
			case Expr::Concat: return "concat";
			case Expr::Extract: return "extract";
			case Expr::ZExt: return "zero_extend";
			case Expr::SExt: return "sign_extend";

			case Expr::Add: return "bvadd";
			case Expr::Sub: return "bvsub";
			case Expr::Mul: return "bvmul";
			case Expr::UDiv: return "bvudiv";
			case Expr::SDiv: return "bvsdiv";
			case Expr::URem: return "bvurem";
			case Expr::SRem: return "bvsrem";


			/* And, Xor, Not and Or are not handled here because there different versions
			 * for different sorts. See printLogicalOrBitVectorExpr()
			 */


			case Expr::Shl: return "bvshl";
			case Expr::LShr: return "bvlshr";
			case Expr::AShr: return "bvashr";

			case Expr::Eq: return "=";

			//Not Equal does not exist directly in SMTLIBv2

			case Expr::Ult: return "bvult";
			case Expr::Ule: return "bvule";
			case Expr::Ugt: return "bvugt";
			case Expr::Uge: return "bvuge";

			case Expr::Slt: return "bvslt";
			case Expr::Sle: return "bvsle";
			case Expr::Sgt: return "bvsgt";
			case Expr::Sge: return "bvsge";

			default:
				return "<error>";

		}
	}

	void ExprSMTLIBPrinter::printUpdatesAndArray(const UpdateNode* un, const Array* root)
	{
		if(un!=NULL)
		{
			*p << "(store ";
			p->pushIndent();
			printSeperator();

			//recurse to get the array or update that this store operations applies to
			printUpdatesAndArray(un->next,root);

			printSeperator();

			//print index
			printExpression(un->index,SORT_BITVECTOR);
			printSeperator();

			//print value that is assigned to this index of the array
			printExpression(un->value,SORT_BITVECTOR);

			p->popIndent();
			printSeperator();
			*p << ")";
		}
		else
		{
			//The base case of the recursion
			*p << root->name;
		}

	}

	void ExprSMTLIBPrinter::scanAll()
	{
		//perform scan of all expressions
		for(ConstraintManager::const_iterator i= query->constraints.begin(); i != query->constraints.end(); i++)
			scan(*i);

		//Scan the query too
		scan(query->expr);
	}

	void ExprSMTLIBPrinter::generateOutput()
	{
		if(p==NULL || query == NULL || o ==NULL)
		{
			std::cerr << "ExprSMTLIBPrinter::generateOutput() Can't print SMTLIBv2. Output or query bad!" << std::endl;
			return;
		}

		if(humanReadable) printNotice();
		printOptions();
		printSetLogic();
		printArrayDeclarations();
		printConstraints();
		printQuery();
		printAction();
		printExit();
	}

	void ExprSMTLIBPrinter::printSetLogic()
	{
		*o << "(set-logic ";
		switch(logicToUse)
		{
		case QF_ABV: *o << "QF_ABV"; break;
		case QF_AUFBV: *o << "QF_AUFBV" ; break;
		}
		*o << " )" << std::endl;
	}


	void ExprSMTLIBPrinter::printArrayDeclarations()
	{
		//Assume scan() has been called
		if(humanReadable)
			*o << "; Array declarations" << endl;

		//declare arrays
		for(set<const Array*>::iterator it = usedArrays.begin(); it != usedArrays.end(); it++)
		{
			*o << "(declare-fun " << (*it)->name << " () "
				 "(Array (_ BitVec " << (*it)->getDomain() << ") "
				 "(_ BitVec " << (*it)->getRange() << ") ) )" << endl;
		}

		//Set array values for constant values
		if(haveConstantArray)
		{
			if(humanReadable)
				*o << "; Constant Array Definitions" << endl;

			const Array* array;

			//loop over found arrays
			for(set<const Array*>::iterator it = usedArrays.begin(); it != usedArrays.end(); it++)
			{
				array= *it;
				int byteIndex=0;
				if(array->isConstantArray())
				{
					/*loop over elements in the array and generate an assert statement
					  for each one
					 */
					for(vector< ref<ConstantExpr> >::const_iterator ce= array->constantValues.begin();
							ce != array->constantValues.end(); ce++, byteIndex++)
					{
						*p << "(assert (";
						p->pushIndent();
						*p <<           "= ";
						p->pushIndent();
						printSeperator();

						*p << "(select " << array->name << " (_ bv" << byteIndex << " " << array->getDomain() << ") )";
						printSeperator();
						printConstant((*ce));

						p->popIndent();
						printSeperator();
						*p << ")";
						p->popIndent();
						printSeperator();
						*p << ")";

						p->breakLineI();

					}
				}
			}
		}
	}

	void ExprSMTLIBPrinter::printConstraints()
	{
		if(humanReadable)
			*o << "; Constraints" << endl;

		//Generate assert statements for each constraint
		for(ConstraintManager::const_iterator i= query->constraints.begin(); i != query->constraints.end(); i++)
		{
			*p << "(assert ";
			p->pushIndent();
			printSeperator();

			//recurse into Expression
			printExpression(*i,SORT_BOOL);

			p->popIndent();
			printSeperator();
			*p << ")"; p->breakLineI();
		}

	}

	void ExprSMTLIBPrinter::printAction()
	{
		//Ask solver to check for satisfiability
		*o << "(check-sat)" << endl;

		/* If we has arrays to find the values of then we'll
		 * ask the solver for the value of each bitvector in each array
		 */
		if(arraysToCallGetValueOn!=NULL && !arraysToCallGetValueOn->empty())
		{

			const Array* theArray=0;

			//loop over the array names
			for(vector<const Array*>::const_iterator it = arraysToCallGetValueOn->begin(); it != arraysToCallGetValueOn->end(); it++)
			{
				theArray=*it;
				//Loop over the array indices
				for(unsigned int index=0; index < theArray->size; ++index)
				{
					*o << "(get-value ( (select " << (**it).name <<
					     " (_ bv" << index << " " << theArray->getDomain() << ") ) ) )" << endl;
				}

			}


		}
	}

	void ExprSMTLIBPrinter::scan(const ref<Expr>& e)
	{
		if(e.isNull())
		{
			std::cerr << "ExprSMTLIBPrinter::scan() : Found NULL expression!" << std::endl;
			return;
		}

		if(isa<ConstantExpr>(e))
			return; //we don't need to scan simple constants

		if(const ReadExpr* re = dyn_cast<ReadExpr>(e))
		{

			//Attempt to insert array and if array wasn't present before do more things
			if(usedArrays.insert(re->updates.root).second)
			{

				//check if the array is constant
				if( re->updates.root->isConstantArray())
					haveConstantArray=true;

				//scan the update list
				scanUpdates(re->updates.head);

			}

		}

		//recurse into the children
		Expr* ep = e.get();
		for(unsigned int i=0; i < ep->getNumKids(); i++)
			scan(ep->getKid(i));
	}


	void ExprSMTLIBPrinter::scanUpdates(const UpdateNode* un)
	{
		while(un != NULL)
		{
			scan(un->index);
			scan(un->value);
			un= un->next;
		}
	}


	void ExprSMTLIBPrinter::printExit()
	{
		*o << "(exit)" << endl;
	}

	bool ExprSMTLIBPrinter::setLogic(SMTLIBv2Logic l)
	{
		if(l > QF_AUFBV)
			return false;

		logicToUse=l;
		return true;
	}

	void ExprSMTLIBPrinter::printSeperator()
	{
		if(humanReadable)
			p->breakLineI();
		else
			p->write(" ");
	}

	void ExprSMTLIBPrinter::printNotice()
	{
		*o << "; This file conforms to SMTLIBv2 and was generated by KLEE" << endl;
	}

	void ExprSMTLIBPrinter::setHumanReadable(bool hr)
	{
		humanReadable=hr;
	}

	void ExprSMTLIBPrinter::printOptions()
	{
		//Print out SMTLIBv2 boolean options
		for(std::map<SMTLIBboolOptions,bool>::const_iterator i= smtlibBoolOptions.begin(); i!= smtlibBoolOptions.end(); i++)
		{
			*o << "(set-option :" << getSMTLIBOptionString(i->first) <<
			" " << ((i->second)?"true":"false") << ")" << endl;
		}
	}

	void ExprSMTLIBPrinter::printQuery()
	{
		if(humanReadable)
		{
			*p << "; Query from solver turned into an assert";
			p->breakLineI();
		}

		p->pushIndent();
		*p << "(assert";
		p->pushIndent();
		printSeperator();

		printExpression(queryAssert,SORT_BOOL);

		p->popIndent();
		printSeperator();
		*p << ")";
		p->popIndent();
		p->breakLineI();
	}

	ExprSMTLIBPrinter::SMTLIB_SORT ExprSMTLIBPrinter::getSort(const ref<Expr>& e)
	{
		/* We could handle every operator in a large switch statement,
		 * but this seems more elegant.
		 */

		if(e->getKind() == Expr::Extract)
		{
			/* This is a special corner case. In most cases if a node in the expression tree
			 * is of width 1 it should be considered as SORT_BOOL. However it is possible to
			 * perform an extract operation on a SORT_BITVECTOR and produce a SORT_BITVECTOR of length 1.
			 * The ((_ extract i j) () ) operation in SMTLIBv2 always produces SORT_BITVECTOR
			 */
			return SORT_BITVECTOR;
		}
		else
			return (e->getWidth() == Expr::Bool)?(SORT_BOOL):(SORT_BITVECTOR);
	}

	void ExprSMTLIBPrinter::printCastToSort(const ref<Expr>& e, ExprSMTLIBPrinter::SMTLIB_SORT sort)
	{
		switch(sort)
		{
			case SORT_BITVECTOR:
				if(humanReadable)
				{
					p->breakLineI(); *p << ";Performing implicit bool to bitvector cast"; p->breakLine();
				}
				//We assume the e is a bool that we need to cast to a bitvector sort.
				*p << "(ite"; p->pushIndent(); printSeperator();
				printExpression(e,SORT_BOOL); printSeperator();
				*p << "(_ bv1 1)" ; printSeperator(); //printing the "true" bitvector
				*p << "(_ bv0 1)" ; p->popIndent(); printSeperator(); //printing the "false" bitvector
				*p << ")";
				break;
			case SORT_BOOL:
			{
				/* We make the assumption (might be wrong) that any bitvector whos unsigned decimal value is
				 * is zero is interpreted as "false", otherwise it is true.
				 *
				 * This may not be the interpretation we actually want!
				 */
				Expr::Width bitWidth=e->getWidth();
				if(humanReadable)
				{
					p->breakLineI(); *p << ";Performing implicit bitvector to bool cast"; p->breakLine();
				}
				*p << "(bvugt"; p->pushIndent(); printSeperator();
				// We assume is e is a bitvector
				printExpression(e,SORT_BITVECTOR); printSeperator();
				*p << "(_ bv0 " << bitWidth << ")"; p->popIndent(); printSeperator(); //Zero bitvector of required width
				*p << ")";

				if(bitWidth!=Expr::Bool)
					std::cerr << "ExprSMTLIBPrinter : Warning. Casting a bitvector (length " << bitWidth << ") to bool!" << std::endl;

			}
				break;
			default:
				assert(0 && "Unsupported cast!");
		}
	}

	void ExprSMTLIBPrinter::printSelectExpr(const ref<SelectExpr>& e, ExprSMTLIBPrinter::SMTLIB_SORT s)
	{
		//This is the if-then-else expression

		*p << "(" << getSMTLIBKeyword(e) << " ";
		p->pushIndent(); //add indent for recursive call

			//The condition
			printSeperator();
			printExpression(e->getKid(0),SORT_BOOL);

			/* This operator is special in that the remaining children
			 * can be of any sort.
			 */

			//if true
			printSeperator();
			printExpression(e->getKid(1),s);

			//if false
			printSeperator();
			printExpression(e->getKid(2),s);


		p->popIndent(); //pop indent added for recursive call
		printSeperator();
		*p << ")";
	}

	void ExprSMTLIBPrinter::printSortArgsExpr(const ref<Expr>& e, ExprSMTLIBPrinter::SMTLIB_SORT s)
	{
		*p << "(" << getSMTLIBKeyword(e) << " ";
		p->pushIndent(); //add indent for recursive call

		//loop over children and recurse into each expecting they are of sort "s"
		for(unsigned int i=0; i < e->getNumKids(); i++)
		{
			printSeperator();
			printExpression(e->getKid(i),s);
		}

		p->popIndent(); //pop indent added for recursive call
		printSeperator();
		*p << ")";
	}

	void ExprSMTLIBPrinter::printLogicalOrBitVectorExpr(const ref<Expr>& e, ExprSMTLIBPrinter::SMTLIB_SORT s)
	{
		/* For these operators it is the case that the expected sort is the same as the sorts
		 * of the arguments.
		 */

		*p << "(";
		switch(e->getKind())
		{
			case Expr::And:
				*p << ((s==SORT_BITVECTOR)?"bvand":"and");
				break;
			case Expr::Not:
				*p << ((s==SORT_BITVECTOR)?"bvnot":"not");
				break;
			case Expr::Or:
				*p << ((s==SORT_BITVECTOR)?"bvor":"or");
				break;

			case Expr::Xor:
				*p << ((s==SORT_BITVECTOR)?"bvxor":"xor");
				break;
			default:
				*p << "ERROR"; // this shouldn't happen
		}
		*p << " ";

		p->pushIndent(); //add indent for recursive call

		//loop over children and recurse into each expecting they are of sort "s"
		for(unsigned int i=0; i < e->getNumKids(); i++)
		{
			printSeperator();
			printExpression(e->getKid(i),s);
		}

		p->popIndent(); //pop indent added for recursive call
		printSeperator();
		*p << ")";
	}

	void ExprSMTLIBPrinter::negateQueryExpression()
	{
		//Negating the query
		queryAssert = Expr::createIsZero(query->expr);
	}

	bool ExprSMTLIBPrinter::setSMTLIBboolOption(SMTLIBboolOptions option, SMTLIBboolValues value)
	{
		std::pair< std::map<SMTLIBboolOptions,bool>::iterator, bool> thePair;
		bool theValue=  (value==OPTION_TRUE)?true:false;

		switch(option)
		{
			case PRINT_SUCCESS:
			case PRODUCE_MODELS:
			case INTERACTIVE_MODE:
				thePair=smtlibBoolOptions.insert(std::pair<SMTLIBboolOptions,bool>(option,theValue));

				if(value== OPTION_DEFAULT)
				{
					//we should unset (by removing from map) this option so the solver uses its default
					smtlibBoolOptions.erase(thePair.first);
					return true;
				}

				if(!thePair.second)
				{
					//option was already present so modify instead.
					thePair.first->second=value;
				}
				return true;
			default:
				return false;

		}
	}

	void ExprSMTLIBPrinter::setArrayValuesToGet(const std::vector<const Array*>& a)
	{
		arraysToCallGetValueOn = &a;

		//This option must be set in order to use the SMTLIBv2 command (get-value () )
		if(!a.empty())
			setSMTLIBboolOption(PRODUCE_MODELS,OPTION_TRUE);

		/* There is a risk that users will ask about array values that aren't
		 * even in the query. We should add them to the usedArrays list and hope
		 * that the solver knows what to do when we ask for the values of arrays
		 * that don't feature in our query!
		 */
		for(vector<const Array*>::const_iterator i = a.begin(); i!= a.end() ; ++i)
		{
			usedArrays.insert(*i);
		}

	}

const char* ExprSMTLIBPrinter::getSMTLIBOptionString(ExprSMTLIBPrinter::SMTLIBboolOptions option)
{
	switch(option)
	{
		case PRINT_SUCCESS: return "print-success";
		case PRODUCE_MODELS: return "produce-models";
		case INTERACTIVE_MODE: return "interactive-mode";
		default:
			return "unknown-option";
	}
}

}