source: src/SynTree/TypeSubstitution.cc@ 0322865c

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// TypeSubstitution.cc --
//
// Author           : Richard C. Bilson
// Created On       : Mon May 18 07:44:20 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Thu Mar 16 15:54:35 2017
// Update Count     : 4
//

#include "Type.h"
#include "TypeSubstitution.h"

TypeSubstitution::TypeSubstitution() {
}

TypeSubstitution::TypeSubstitution( const TypeSubstitution &other ) {
        initialize( other, *this );
}

TypeSubstitution::~TypeSubstitution() {
        for ( TypeEnvType::iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) {
                delete( i->second );
        }
        for ( VarEnvType::iterator i = varEnv.begin(); i != varEnv.end(); ++i ) {
                delete( i->second );
        }
}

TypeSubstitution &TypeSubstitution::operator=( const TypeSubstitution &other ) {
        if ( this == &other ) return *this;
        initialize( other, *this );
        return *this;
}

void TypeSubstitution::initialize( const TypeSubstitution &src, TypeSubstitution &dest ) {
        dest.typeEnv.clear();
        dest.varEnv.clear();
        dest.add( src );
}

void TypeSubstitution::add( const TypeSubstitution &other ) {
        for ( TypeEnvType::const_iterator i = other.typeEnv.begin(); i != other.typeEnv.end(); ++i ) {
                typeEnv[ i->first ] = i->second->clone();
        } // for
        for ( VarEnvType::const_iterator i = other.varEnv.begin(); i != other.varEnv.end(); ++i ) {
                varEnv[ i->first ] = i->second->clone();
        } // for
}

void TypeSubstitution::add( std::string formalType, Type *actualType ) {
        TypeEnvType::iterator i = typeEnv.find( formalType );
        if ( i != typeEnv.end() ) {
                delete i->second;
        } // if
        typeEnv[ formalType ] = actualType->clone();
}

void TypeSubstitution::remove( std::string formalType ) {
        TypeEnvType::iterator i = typeEnv.find( formalType );
        if ( i != typeEnv.end() ) {
                delete i->second;
                typeEnv.erase( formalType );
        } // if
}

Type *TypeSubstitution::lookup( std::string formalType ) const {
        TypeEnvType::const_iterator i = typeEnv.find( formalType );

        // break on not in substitution set
        if ( i == typeEnv.end() ) return 0;

        // attempt to transitively follow TypeInstType links.
        while ( TypeInstType *actualType = dynamic_cast< TypeInstType* >( i->second ) ) {
                const std::string& typeName = actualType->get_name();

                // break cycles in the transitive follow
                if ( formalType == typeName ) break;

                // Look for the type this maps to, returning previous mapping if none-such
                i = typeEnv.find( typeName );
                if ( i == typeEnv.end() ) return actualType;
        }

        // return type from substitution set
        return i->second;

#if 0
        if ( i == typeEnv.end() ) {
                return 0;
        } else {
                return i->second;
        } // if
#endif
}

bool TypeSubstitution::empty() const {
        return typeEnv.empty() && varEnv.empty();
}

void TypeSubstitution::normalize() {
        do {
                subCount = 0;
                freeOnly = true;
                for ( TypeEnvType::iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) {
                        i->second = i->second->acceptMutator( *this );
                }
        } while ( subCount );
}

Type * TypeSubstitution::mutate( TypeInstType *inst ) {
        BoundVarsType::const_iterator bound = boundVars.find( inst->get_name() );
        if ( bound != boundVars.end() ) return inst;

        TypeEnvType::const_iterator i = typeEnv.find( inst->get_name() );
        if ( i == typeEnv.end() ) {
                return inst;
        } else {
///         std::cout << "found " << inst->get_name() << ", replacing with ";
///         i->second->print( std::cout );
///         std::cout << std::endl;
                subCount++;
                Type *newtype = i->second->clone();
                newtype->get_qualifiers() |= inst->get_qualifiers();
                delete inst;
                return newtype;
        } // if
}

Expression * TypeSubstitution::mutate( NameExpr *nameExpr ) {
        VarEnvType::const_iterator i = varEnv.find( nameExpr->get_name() );
        if ( i == varEnv.end() ) {
                return nameExpr;
        } else {
                subCount++;
                delete nameExpr;
                return i->second->clone();
        } // if
}

template< typename TypeClass >
Type *TypeSubstitution::handleType( TypeClass *type ) {
        BoundVarsType oldBoundVars( boundVars );
        // bind type variables from forall-qualifiers
        if ( freeOnly ) {
                for ( Type::ForallList::const_iterator tyvar = type->get_forall().begin(); tyvar != type->get_forall().end(); ++tyvar ) {
                        boundVars.insert( (*tyvar )->get_name() );
                } // for
        } // if
        Type *ret = Mutator::mutate( type );
        boundVars = oldBoundVars;
        return ret;
}

template< typename TypeClass >
Type *TypeSubstitution::handleAggregateType( TypeClass *type ) {
        BoundVarsType oldBoundVars( boundVars );
        // bind type variables from forall-qualifiers
        if ( freeOnly ) {
                for ( Type::ForallList::const_iterator tyvar = type->get_forall().begin(); tyvar != type->get_forall().end(); ++tyvar ) {
                        boundVars.insert( (*tyvar )->get_name() );
                } // for
                // bind type variables from generic type instantiations
                std::list< TypeDecl* > *baseParameters = type->get_baseParameters();
                if ( baseParameters && ! type->get_parameters().empty() ) {
                        for ( std::list< TypeDecl* >::const_iterator tyvar = baseParameters->begin(); tyvar != baseParameters->end(); ++tyvar ) {
                                boundVars.insert( (*tyvar)->get_name() );
                        } // for
                } // if
        } // if
        Type *ret = Mutator::mutate( type );
        boundVars = oldBoundVars;
        return ret;
}

Type * TypeSubstitution::mutate( VoidType *voidType ) {
        return handleType( voidType );
}

Type * TypeSubstitution::mutate( BasicType *basicType ) {
        return handleType( basicType );
}

Type * TypeSubstitution::mutate( PointerType *pointerType ) {
        return handleType( pointerType );
}

Type * TypeSubstitution::mutate( ArrayType *arrayType ) {
        return handleType( arrayType );
}

Type * TypeSubstitution::mutate( FunctionType *functionType ) {
        return handleType( functionType );
}

Type * TypeSubstitution::mutate( StructInstType *aggregateUseType ) {
        return handleAggregateType( aggregateUseType );
}

Type * TypeSubstitution::mutate( UnionInstType *aggregateUseType ) {
        return handleAggregateType( aggregateUseType );
}

Type * TypeSubstitution::mutate( EnumInstType *aggregateUseType ) {
        return handleType( aggregateUseType );
}

Type * TypeSubstitution::mutate( TraitInstType *aggregateUseType ) {
        return handleType( aggregateUseType );
}

Type * TypeSubstitution::mutate( TupleType *tupleType ) {
        return handleType( tupleType );
}

Type * TypeSubstitution::mutate( VarArgsType *varArgsType ) {
        return handleType( varArgsType );
}

Type * TypeSubstitution::mutate( ZeroType *zeroType ) {
        return handleType( zeroType );
}

Type * TypeSubstitution::mutate( OneType *oneType ) {
        return handleType( oneType );
}

TypeSubstitution * TypeSubstitution::acceptMutator( Mutator & mutator ) {
        for ( auto & p : typeEnv ) {
                p.second = maybeMutate( p.second, mutator );
        }
        for ( auto & p : varEnv ) {
                p.second = maybeMutate( p.second, mutator );
        }
        return this;
}

void TypeSubstitution::print( std::ostream &os, int indent ) const {
        os << std::string( indent, ' ' ) << "Types:" << std::endl;
        for ( TypeEnvType::const_iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) {
                os << std::string( indent+2, ' ' ) << i->first << " -> ";
                i->second->print( os, indent+4 );
                os << std::endl;
        } // for
        os << std::string( indent, ' ' ) << "Non-types:" << std::endl;
        for ( VarEnvType::const_iterator i = varEnv.begin(); i != varEnv.end(); ++i ) {
                os << std::string( indent+2, ' ' ) << i->first << " -> ";
                i->second->print( os, indent+4 );
                os << std::endl;
        } // for
}

std::ostream & operator<<( std::ostream & out, const TypeSubstitution & sub ) {
        sub.print( out );
        return out;
}


// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //