source: src/Tuples/TupleExpansionNew.cpp @ 637240f

//
// 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.
//
// TupleExpansionNew.cpp --
//
// Author           : Henry Xue
// Created On       : Mon Aug 23 15:36:09 2021
// Last Modified By : Henry Xue
// Last Modified On : Mon Aug 23 15:36:09 2021
// Update Count     : 1
//

#include "Tuples.h"

namespace Tuples {
namespace {
        struct MemberTupleExpander final : public ast::WithShortCircuiting, public ast::WithVisitorRef< MemberTupleExpander > {
                void previsit( const ast::UntypedMemberExpr * ) { visit_children = false; }
        const ast::Expr * postvisit( const ast::UntypedMemberExpr * memberExpr );
        };
} // namespace

void expandMemberTuples( ast::TranslationUnit & translationUnit ) {
        ast::Pass< MemberTupleExpander >::run( translationUnit );
}

namespace {
        namespace {
                /// given a expression representing the member and an expression representing the aggregate,
                /// reconstructs a flattened UntypedMemberExpr with the right precedence
                const ast::Expr * reconstructMemberExpr( const ast::Expr * member, const ast::Expr * aggr, const CodeLocation & loc ) {
                        if ( auto memberExpr = dynamic_cast< const ast::UntypedMemberExpr * >( member ) ) {
                                // construct a new UntypedMemberExpr with the correct structure , and recursively
                                // expand that member expression.
                                ast::Pass< MemberTupleExpander > expander;
                                auto inner = new ast::UntypedMemberExpr( loc, memberExpr->aggregate, aggr );
                                auto newMemberExpr = new ast::UntypedMemberExpr( loc, memberExpr->member, inner );
                                //delete memberExpr;
                                return newMemberExpr->accept( expander );
                        } else {
                                // not a member expression, so there is nothing to do but attach and return
                                return new ast::UntypedMemberExpr( loc, member, aggr );
                        }
                }
        }

        const ast::Expr * MemberTupleExpander::postvisit( const ast::UntypedMemberExpr * memberExpr ) {
                const CodeLocation loc = memberExpr->location;
        if ( auto tupleExpr = memberExpr->member.as< ast::UntypedTupleExpr >() ) {
                        auto mutExpr = mutate( tupleExpr );
                        ast::ptr< ast::Expr > aggr = memberExpr->aggregate->accept( *visitor );
                        // aggregate expressions which might be impure must be wrapped in unique expressions
                        if ( Tuples::maybeImpureIgnoreUnique( memberExpr->aggregate ) ) aggr = new ast::UniqueExpr( loc, aggr );
                        for ( auto & expr : mutExpr->exprs ) {
                                expr = reconstructMemberExpr( expr, aggr, loc );
                        }
                        //delete aggr;
                        return mutExpr;
                } else {
                        // there may be a tuple expr buried in the aggregate
                        return new ast::UntypedMemberExpr( loc, memberExpr->member, memberExpr->aggregate->accept( *visitor ) );
                }
        }
} // namespace
} // namespace Tuples