source: src/SynTree/GcTracer.h @ 3205495

//
// 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.
//
// GcTracer.h --
//
// Author           : Aaron B. Moss
// Created On       : Thu Mar 15 14:47:00 2018
// Last Modified By : Aaron B. Moss
// Last Modified On : Thu Mar 15 14:47:00 2018
// Update Count     : 1
//

#pragma once

#include <list>

#include "BaseSyntaxNode.h"
#include "Expression.h"
#include "Type.h"

#include "Common/GC.h"
#include "Common/PassVisitor.h"

class Expression;

/// Implements `trace` method for syntax nodes
class GcTracer final : public WithShortCircuiting, public WithVisitorRef<GcTracer> {
        const GC& gc;

public:
        GcTracer( const GC& gc ) : gc(gc) {}

        // mark node and children

        void previsit( BaseSyntaxNode * node ) {
                // skip tree if already seen
                // xxx - this should be uncommented (it breaks object cycles), but at the moment it seems 
                // like the object cycles don't happen and other bugs do
                // if ( node->mark == gc.mark ) {
                //      visit_children = false;
                //      return;
                // }

                // mark node
                node->mark = gc.mark;
        }

        // add visits left out by PassVisitor

        void postvisit( Expression* expr ) {
                maybeAccept( expr->env, *visitor );
        }

        void postvisit( UntypedExpr* expr ) {
                postvisit( static_cast<Expression*>(expr) );
                maybeAccept( expr->function, *visitor );
        }

        void postvisit( Type* type ) {
                acceptAll( type->attributes, *visitor );
        }

        void postvisit( PointerType* type ) {
                postvisit( static_cast<Type*>(type) );
                maybeAccept( type->dimension, *visitor );
        }
};

/// Traces entire translation unit recursively
static inline const GC& operator<< ( const GC& gc, const std::list<Declaration*>& translationUnit ) {
        PassVisitor<GcTracer> tracer{ gc };
        acceptAll( const_cast<std::list<Declaration*>&>( translationUnit ), tracer );
        return gc;
}

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