source: translator/ResolvExpr/Resolver.cc@ fe3b61b

#include "Resolver.h"
#include "AlternativeFinder.h"
#include "Alternative.h"
#include "RenameVars.h"
#include "ResolveTypeof.h"
#include "SynTree/Statement.h"
#include "SynTree/Type.h"
#include "SynTree/Expression.h"
#include "SynTree/Initializer.h"
#include "SymTab/Indexer.h"
#include "utility.h"

#include <iostream>
using namespace std;

namespace ResolvExpr {
    class Resolver : public SymTab::Indexer {
      public:
        Resolver() : SymTab::Indexer( false ), switchType( 0 ) {}
  
        virtual void visit( FunctionDecl *functionDecl );
        virtual void visit( ObjectDecl *functionDecl );
        virtual void visit( TypeDecl *typeDecl );

        virtual void visit( ExprStmt *exprStmt );
        virtual void visit( IfStmt *ifStmt );
        virtual void visit( WhileStmt *whileStmt );
        virtual void visit( ForStmt *forStmt );
        virtual void visit( SwitchStmt *switchStmt );
        virtual void visit( ChooseStmt *switchStmt );
        virtual void visit( CaseStmt *caseStmt );
        virtual void visit( ReturnStmt *returnStmt );

        virtual void visit( SingleInit *singleInit );
        virtual void visit( ListInit *listInit );
      private:
        std::list< Type * > functionReturn;
        Type *initContext;
        Type *switchType;
    };

    void resolve( std::list< Declaration * > translationUnit ) {
        Resolver resolver;
        acceptAll( translationUnit, resolver );
#if 0
        for ( std::list< Declaration * >::iterator i = translationUnit.begin(); i != translationUnit.end(); ++i ) {
            (*i)->print( std::cerr );
            (*i)->accept( resolver );
        } // for
#endif
    }

    Expression *resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer ) {
        TypeEnvironment env;
        return resolveInVoidContext( expr, indexer, env );
    }

    namespace {
        void finishExpr( Expression *expr, const TypeEnvironment &env ) {
            expr->set_env( new TypeSubstitution );
            env.makeSubstitution( *expr->get_env() );
        }

        Expression *findVoidExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
            global_renamer.reset();
            TypeEnvironment env;
            Expression *newExpr = resolveInVoidContext( untyped, indexer, env );
            finishExpr( newExpr, env );
            return newExpr;
        }
  
        Expression *findSingleExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
            TypeEnvironment env;
            AlternativeFinder finder( indexer, env );
            finder.find( untyped );
#if 0
            if ( finder.get_alternatives().size() != 1 ) {
                std::cout << "untyped expr is ";
                untyped->print( std::cout );
                std::cout << std::endl << "alternatives are:";
                for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
                    i->print( std::cout );
                } // for
            } // if
#endif
            assert( finder.get_alternatives().size() == 1 );
            Alternative &choice = finder.get_alternatives().front();
            Expression *newExpr = choice.expr->clone();
            finishExpr( newExpr, choice.env );
            return newExpr;
        }

        bool isIntegralType( Type *type ) {
            if ( dynamic_cast< EnumInstType * >( type ) ) {
                return true;
            } else if ( BasicType *bt = dynamic_cast< BasicType * >( type ) ) {
                return bt->isInteger();
            } else {
                return true;
            } // if
        }
  
        Expression *findIntegralExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
            TypeEnvironment env;
            AlternativeFinder finder( indexer, env );
            finder.find( untyped );
#if 0
            if ( finder.get_alternatives().size() != 1 ) {
                std::cout << "untyped expr is ";
                untyped->print( std::cout );
                std::cout << std::endl << "alternatives are:";
                for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
                    i->print( std::cout );
                } // for
            } // if
#endif
            Expression *newExpr = 0;
            const TypeEnvironment *newEnv = 0;
            for ( AltList::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
                if ( i->expr->get_results().size() == 1 && isIntegralType( i->expr->get_results().front() ) ) {
                    if ( newExpr ) {
                        throw SemanticError( "Too many interpretations for switch control expression", untyped );
                    } else {
                        newExpr = i->expr->clone();
                        newEnv = &i->env;
                    } // if
                } // if
            } // for
            if ( !newExpr ) {
                throw SemanticError( "Too many interpretations for switch control expression", untyped );
            } // if
            finishExpr( newExpr, *newEnv );
            return newExpr;
        }
  
    }
  
    void Resolver::visit( ObjectDecl *objectDecl ) {
        Type *new_type = resolveTypeof( objectDecl->get_type(), *this );
        objectDecl->set_type( new_type );
        initContext = new_type;
        SymTab::Indexer::visit( objectDecl );
    }
  
    void Resolver::visit( TypeDecl *typeDecl ) {
        if ( typeDecl->get_base() ) {
            Type *new_type = resolveTypeof( typeDecl->get_base(), *this );
            typeDecl->set_base( new_type );
        } // if
        SymTab::Indexer::visit( typeDecl );
    }
  
    void Resolver::visit( FunctionDecl *functionDecl ) {
#if 0
        std::cout << "resolver visiting functiondecl ";
        functionDecl->print( std::cout );
        std::cout << std::endl;
#endif
        Type *new_type = resolveTypeof( functionDecl->get_type(), *this );
        functionDecl->set_type( new_type );
        std::list< Type * > oldFunctionReturn = functionReturn;
        functionReturn.clear();
        for ( std::list< DeclarationWithType * >::const_iterator i = functionDecl->get_functionType()->get_returnVals().begin(); i != functionDecl->get_functionType()->get_returnVals().end(); ++i ) {
            functionReturn.push_back( (*i)->get_type() );
        } // for
        SymTab::Indexer::visit( functionDecl );
        functionReturn = oldFunctionReturn;
    }

    void Resolver::visit( ExprStmt *exprStmt ) {
        if ( exprStmt->get_expr() ) {
            Expression *newExpr = findVoidExpression( exprStmt->get_expr(), *this );
            delete exprStmt->get_expr();
            exprStmt->set_expr( newExpr );
        } // if
    }

    void Resolver::visit( IfStmt *ifStmt ) {
        Expression *newExpr = findSingleExpression( ifStmt->get_condition(), *this );
        delete ifStmt->get_condition();
        ifStmt->set_condition( newExpr );
        Visitor::visit( ifStmt );
    }

    void Resolver::visit( WhileStmt *whileStmt ) {
        Expression *newExpr = findSingleExpression( whileStmt->get_condition(), *this );
        delete whileStmt->get_condition();
        whileStmt->set_condition( newExpr );
        Visitor::visit( whileStmt );
    }

    void Resolver::visit( ForStmt *forStmt ) {
        Expression *newExpr;
        if ( forStmt->get_condition() ) {
            newExpr = findSingleExpression( forStmt->get_condition(), *this );
            delete forStmt->get_condition();
            forStmt->set_condition( newExpr );
        } // if
  
        if ( forStmt->get_increment() ) {
            newExpr = findVoidExpression( forStmt->get_increment(), *this );
            delete forStmt->get_increment();
            forStmt->set_increment( newExpr );
        } // if
  
        Visitor::visit( forStmt );
    }

    template< typename SwitchClass >
    void handleSwitchStmt( SwitchClass *switchStmt, SymTab::Indexer &visitor ) {
        Expression *newExpr;
        newExpr = findIntegralExpression( switchStmt->get_condition(), visitor );
        delete switchStmt->get_condition();
        switchStmt->set_condition( newExpr );
  
        visitor.Visitor::visit( switchStmt );
    }

    void Resolver::visit( SwitchStmt *switchStmt ) {
        handleSwitchStmt( switchStmt, *this );
    }

    void Resolver::visit( ChooseStmt *switchStmt ) {
        handleSwitchStmt( switchStmt, *this );
    }

    void Resolver::visit( CaseStmt *caseStmt ) {
        Visitor::visit( caseStmt );
    }

    void Resolver::visit( ReturnStmt *returnStmt ) {
        if ( returnStmt->get_expr() ) {
            CastExpr *castExpr = new CastExpr( returnStmt->get_expr() );
            cloneAll( functionReturn, castExpr->get_results() );
            Expression *newExpr = findSingleExpression( castExpr, *this );
            delete castExpr;
            returnStmt->set_expr( newExpr );
        } // if
    }

    void Resolver::visit( SingleInit *singleInit ) {
        if ( singleInit->get_value() ) {
            CastExpr *castExpr = new CastExpr( singleInit->get_value(), initContext->clone() );
            Expression *newExpr = findSingleExpression( castExpr, *this );
            delete castExpr;
            singleInit->set_value( newExpr );
        } // if
//      singleInit->get_value()->accept( *this );
    }

    void Resolver::visit( ListInit *listInit ) {
        if ( ArrayType *at = dynamic_cast<ArrayType*>(initContext) ) {
            initContext = at->get_base();
            Visitor::visit( listInit );
        } else if ( StructInstType *st = dynamic_cast<StructInstType*>(initContext) ) {
            StructDecl *baseStruct = st->get_baseStruct();
            std::list<Declaration *>::iterator iter1( baseStruct->get_members().begin() );
            std::list<Initializer *>::iterator iter2( listInit->begin_initializers() );
            for ( ; iter1 != baseStruct->get_members().end() && iter2 != listInit->end_initializers() ; ++iter1, ++iter2 ) {
                DeclarationWithType *dt = dynamic_cast<DeclarationWithType *>( *iter1 );
                initContext = dt->get_type();
                (*iter2)->accept( *this );
            }
        } else if ( UnionInstType *st = dynamic_cast<UnionInstType*>(initContext) ) {
            DeclarationWithType *dt = dynamic_cast<DeclarationWithType *>( *st->get_baseUnion()->get_members().begin() );
            initContext = dt->get_type();
            (*listInit->begin_initializers())->accept( *this );
        } // if
    }
} // namespace ResolvExpr