source: src/ResolvExpr/TypeEnvironment.cc @ e04aec4

//
// 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.
//
// TypeEnvironment.cc --
//
// Author           : Richard C. Bilson
// Created On       : Sun May 17 12:19:47 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Sun May 17 12:23:36 2015
// Update Count     : 3
//

#include <cassert>                     // for assert
#include <algorithm>                   // for copy, set_intersection
#include <iterator>                    // for ostream_iterator, insert_iterator
#include <utility>                     // for pair, move

#include "Common/utility.h"            // for maybeClone
#include "SynTree/Type.h"              // for Type, FunctionType, Type::Fora...
#include "SynTree/TypeSubstitution.h"  // for TypeSubstitution
#include "TypeEnvironment.h"

namespace ResolvExpr {
        void printAssertionSet( const AssertionSet &assertions, std::ostream &os, int indent ) {
                for ( AssertionSet::const_iterator i = assertions.begin(); i != assertions.end(); ++i ) {
                        i->first->print( os, indent );
                        if ( i->second.isUsed ) {
                                os << "(used)";
                        } else {
                                os << "(not used)";
                        } // if
                } // for
        }

        void printOpenVarSet( const OpenVarSet &openVars, std::ostream &os, int indent ) {
                os << std::string( indent, ' ' );
                for ( OpenVarSet::const_iterator i = openVars.begin(); i != openVars.end(); ++i ) {
                        os << i->first << "(" << i->second << ") ";
                } // for
        }

        void EqvClass::initialize( const EqvClass &src, EqvClass &dest ) {
                initialize( src, dest, src.type );
        }

        void EqvClass::initialize( const EqvClass &src, EqvClass &dest, const Type *ty ) {
                dest.vars = src.vars;
                dest.type = maybeClone( ty );
                dest.allowWidening = src.allowWidening;
                dest.data = src.data;
        }

        EqvClass::EqvClass() : type( nullptr ), allowWidening( true ) {
        }

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

        EqvClass::EqvClass( const EqvClass &other, const Type *ty ) {
                initialize( other, *this, ty );
        }

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

        EqvClass::~EqvClass() {
                delete type;
        }

        void EqvClass::print( std::ostream &os, Indenter indent ) const {
                os << "( ";
                std::copy( vars.begin(), vars.end(), std::ostream_iterator< std::string >( os, " " ) );
                os << ")";
                if ( type ) {
                        os << " -> ";
                        type->print( os, indent+1 );
                } // if
                if ( ! allowWidening ) {
                        os << " (no widening)";
                } // if
                os << std::endl;
        }

        const EqvClass* TypeEnvironment::lookup( const std::string &var ) const {
                for ( std::list< EqvClass >::const_iterator i = env.begin(); i != env.end(); ++i ) {
                        if ( i->vars.find( var ) != i->vars.end() ) {
///       std::cout << var << " is in class ";
///       i->print( std::cout );
                                return &*i;
                        }
///     std::cout << var << " is not in class ";
///     i->print( std::cout );
                } // for
                return nullptr;
        }

        /// Removes any class from env that intersects eqvClass
        void filterOverlappingClasses( std::list<EqvClass> &env, const EqvClass &eqvClass ) {
                for ( auto i = env.begin(); i != env.end(); ) {
                        auto next = i;
                        ++next;
                        std::set<std::string> intersection;
                        std::set_intersection( i->vars.begin(), i->vars.end(), eqvClass.vars.begin(), eqvClass.vars.end(), 
                                std::inserter( intersection, intersection.begin() ) );
                        if ( ! intersection.empty() ) { env.erase( i ); }
                        i = next;
                }
        }

        void TypeEnvironment::add( const EqvClass &eqvClass ) {
                filterOverlappingClasses( env, eqvClass );
                env.push_back( eqvClass );
        }

        void TypeEnvironment::add( EqvClass &&eqvClass ) {
                filterOverlappingClasses( env, eqvClass );
                env.push_back( std::move(eqvClass) );
        }

        void TypeEnvironment::add( const Type::ForallList &tyDecls ) {
                for ( Type::ForallList::const_iterator i = tyDecls.begin(); i != tyDecls.end(); ++i ) {
                        EqvClass newClass;
                        newClass.vars.insert( (*i)->get_name() );
                        newClass.data = TypeDecl::Data{ (*i) };
                        env.push_back( newClass );
                } // for
        }

        void TypeEnvironment::add( const TypeSubstitution & sub ) {
                EqvClass newClass;
                for ( auto p : sub ) {
                        newClass.vars.insert( p.first );
                        newClass.type = p.second->clone();
                        newClass.allowWidening = false;
                        // Minimal assumptions. Not technically correct, but might be good enough, and
                        // is the best we can do at the moment since information is lost in the
                        // transition to TypeSubstitution
                        newClass.data = TypeDecl::Data{ TypeDecl::Dtype, false };
                        add( newClass );
                }
        }

        void TypeEnvironment::makeSubstitution( TypeSubstitution &sub ) const {
                for ( std::list< EqvClass >::const_iterator theClass = env.begin(); theClass != env.end(); ++theClass ) {
                        for ( std::set< std::string >::const_iterator theVar = theClass->vars.begin(); theVar != theClass->vars.end(); ++theVar ) {
///       std::cerr << "adding " << *theVar;
                                if ( theClass->type ) {
///         std::cerr << " bound to ";
///         theClass->type->print( std::cerr );
///         std::cerr << std::endl;
                                        sub.add( *theVar, theClass->type );
                                } else if ( theVar != theClass->vars.begin() ) {
                                        TypeInstType *newTypeInst = new TypeInstType( Type::Qualifiers(), *theClass->vars.begin(), theClass->data.kind == TypeDecl::Ftype );
///         std::cerr << " bound to variable " << *theClass->vars.begin() << std::endl;
                                        sub.add( *theVar, newTypeInst );
                                        delete newTypeInst;
                                } // if
                        } // for
                } // for
///   std::cerr << "input env is:" << std::endl;
///   print( std::cerr, 8 );
///   std::cerr << "sub is:" << std::endl;
///   sub.print( std::cerr, 8 );
                sub.normalize();
        }

        void TypeEnvironment::print( std::ostream &os, Indenter indent ) const {
                for ( const EqvClass & theClass : env ) {
                        theClass.print( os, indent );
                } // for
        }

        std::list< EqvClass >::iterator TypeEnvironment::internal_lookup( const std::string &var ) {
                for ( std::list< EqvClass >::iterator i = env.begin(); i != env.end(); ++i ) {
                        if ( i->vars.find( var ) == i->vars.end() ) {
                                return i;
                        } // if
                } // for
                return env.end();
        }

        void TypeEnvironment::simpleCombine( const TypeEnvironment &second ) {
                env.insert( env.end(), second.env.begin(), second.env.end() );
        }

        void TypeEnvironment::combine( const TypeEnvironment &second, Type *(*combineFunc)( Type*, Type* ) ) {
                TypeEnvironment secondCopy( second );
                for ( std::list< EqvClass >::iterator firstClass = env.begin(); firstClass != env.end(); ++firstClass ) {
                        EqvClass &newClass = *firstClass;
                        std::set< std::string > newVars;
                        for ( std::set< std::string >::const_iterator var = firstClass->vars.begin(); var != firstClass->vars.end(); ++var ) {
                                std::list< EqvClass >::iterator secondClass = secondCopy.internal_lookup( *var );
                                if ( secondClass != secondCopy.env.end() ) {
                                        newVars.insert( secondClass->vars.begin(), secondClass->vars.end() );
                                        if ( secondClass->type ) {
                                                if ( newClass.type ) {
                                                        Type *newType = combineFunc( newClass.type, secondClass->type );
                                                        delete newClass.type;
                                                        newClass.type = newType;
                                                        newClass.allowWidening = newClass.allowWidening && secondClass->allowWidening;
                                                } else {
                                                        newClass.type = secondClass->type->clone();
                                                        newClass.allowWidening = secondClass->allowWidening;
                                                } // if
                                        } // if
                                        secondCopy.env.erase( secondClass );
                                } // if
                        } // for
                        newClass.vars.insert( newVars.begin(), newVars.end() );
                } // for
                for ( std::list< EqvClass >::iterator secondClass = secondCopy.env.begin(); secondClass != secondCopy.env.end(); ++secondClass ) {
                        env.push_back( *secondClass );
                } // for
        }

        void TypeEnvironment::extractOpenVars( OpenVarSet &openVars ) const {
                for ( std::list< EqvClass >::const_iterator eqvClass = env.begin(); eqvClass != env.end(); ++eqvClass ) {
                        for ( std::set< std::string >::const_iterator var = eqvClass->vars.begin(); var != eqvClass->vars.end(); ++var ) {
                                openVars[ *var ] = eqvClass->data;
                        } // for
                } // for
        }

        void TypeEnvironment::addActual( const TypeEnvironment& actualEnv, OpenVarSet& openVars ) {
                for ( const EqvClass& c : actualEnv ) {
                        EqvClass c2 = c;
                        c2.allowWidening = false;
                        for ( const std::string& var : c2.vars ) {
                                openVars[ var ] = c2.data;
                        }
                        env.push_back( std::move(c2) );
                }
        }

        std::ostream & operator<<( std::ostream & out, const TypeEnvironment & env ) {
                env.print( out );
                return out;
        }
} // namespace ResolvExpr

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