source: src/Tuples/TupleExpansion.cc @ 1132b62

//
// 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.
//
// TupleAssignment.cc --
//
// Author           : Rodolfo G. Esteves
// Created On       : Mon May 18 07:44:20 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Mon May 18 15:02:53 2015
// Update Count     : 2
//

#include <iterator>
#include <iostream>
#include <cassert>
#include "Tuples.h"
#include "GenPoly/DeclMutator.h"
#include "SynTree/Mutator.h"
#include "SynTree/Statement.h"
#include "SynTree/Declaration.h"
#include "SynTree/Type.h"
#include "SynTree/Expression.h"
#include "SynTree/Initializer.h"
#include "SymTab/Mangler.h"
#include "Common/ScopedMap.h"
#include "ResolvExpr/typeops.h"

namespace Tuples {
        namespace {
                class UniqueExprExpander : public GenPoly::DeclMutator {
                public:
                        typedef GenPoly::DeclMutator Parent;
                        virtual Expression * mutate( UniqueExpr * unqExpr );
                        std::map< Expression *, ObjectDecl * > decls;
                };

                class TupleAssignExpander : public Mutator {
                public:
                        typedef Mutator Parent;
                        virtual Expression * mutate( TupleAssignExpr * tupleExpr );
                };

                class TupleTypeReplacer : public GenPoly::DeclMutator {
                  public:
                        typedef GenPoly::DeclMutator Parent;

                        virtual Type * mutate( TupleType * tupleType );
                        virtual Type * mutate( FunctionType * ftype );

                        virtual CompoundStmt * mutate( CompoundStmt * stmt ) {
                                typeMap.beginScope();
                                stmt = Parent::mutate( stmt );
                                typeMap.endScope();
                                return stmt;
                        }
                  private:
                        ScopedMap< std::string, StructDecl * > typeMap;
                };

                class TupleIndexExpander : public Mutator {
                public:
                        typedef Mutator Parent;
                        virtual Expression * mutate( TupleIndexExpr * tupleExpr );
                };

                class TupleExprExpander : public Mutator {
                public:
                        typedef Mutator Parent;
                        virtual Expression * mutate( TupleExpr * tupleExpr );
                };
        }

        void expandUniqueExpr( std::list< Declaration * > & translationUnit ) {
                UniqueExprExpander unqExpander;
                unqExpander.mutateDeclarationList( translationUnit );
        }

        void expandTuples( std::list< Declaration * > & translationUnit ) {
                TupleAssignExpander assnExpander;
                mutateAll( translationUnit, assnExpander );

                TupleTypeReplacer replacer;
                replacer.mutateDeclarationList( translationUnit );

                TupleIndexExpander idxExpander;
                mutateAll( translationUnit, idxExpander );

                TupleExprExpander exprExpander;
                mutateAll( translationUnit, exprExpander );
        }

        Expression * UniqueExprExpander::mutate( UniqueExpr * unqExpr ) {
                static UniqueName tempNamer( "_unq_expr_" );
                unqExpr = safe_dynamic_cast< UniqueExpr * > ( Parent::mutate( unqExpr ) );
                if ( ! decls.count( unqExpr->get_expr() ) ) {
                        // xxx - it's possible (likely?) that expressions can appear in the wrong order because of this. Need to ensure they're placed in the correct location.
                        ObjectDecl * decl = new ObjectDecl( tempNamer.newName(), DeclarationNode::NoStorageClass, LinkageSpec::Cforall, nullptr, unqExpr->get_result()->clone(), new SingleInit( unqExpr->get_expr()->clone() ) );
                        decls[unqExpr->get_expr()] = decl;
                        addDeclaration( decl );
                }
                return new VariableExpr( decls[unqExpr->get_expr()] );
        }

        Expression * TupleAssignExpander::mutate( TupleAssignExpr * assnExpr ) {
                // xxx - Parent::mutate?
                CompoundStmt * compoundStmt = new CompoundStmt( noLabels );
                std::list< Statement * > & stmts = compoundStmt->get_kids();
                for ( ObjectDecl * obj : assnExpr->get_tempDecls() ) {
                        stmts.push_back( new DeclStmt( noLabels, obj ) );
                }
                TupleExpr * tupleExpr = new TupleExpr( assnExpr->get_assigns() );
                assert( tupleExpr->get_result() );
                stmts.push_back( new ExprStmt( noLabels, tupleExpr ) );
                assnExpr->get_tempDecls().clear();
                assnExpr->get_assigns().clear();
                delete assnExpr;
                return new StmtExpr( compoundStmt );
        }

        Type * TupleTypeReplacer::mutate( FunctionType * ftype ) {
                // replace multiple-returning functions with functions which return a tuple
                if ( ftype->get_returnVals().size() > 1 ) {
                        TupleType * tupleType = safe_dynamic_cast<TupleType *>( ResolvExpr::extractResultType( ftype ) );
                        ObjectDecl * retVal = new ObjectDecl( "__tuple_ret", DeclarationNode::NoStorageClass, LinkageSpec::C, nullptr, tupleType, nullptr );
                        // xxx - replace all uses of return vals with appropriate tuple index expr
                        deleteAll( ftype->get_returnVals() );
                        ftype->get_returnVals().clear();
                        ftype->get_returnVals().push_back( retVal );
                }
                return Parent::mutate( ftype );
        }

        Type * TupleTypeReplacer::mutate( TupleType * tupleType ) {
                std::string mangleName = SymTab::Mangler::mangleType( tupleType );
                TupleType * newType = safe_dynamic_cast< TupleType * > ( Parent::mutate( tupleType ) );
                if ( ! typeMap.count( mangleName ) ) {
                        // generate struct type to replace tuple type
                        StructDecl * decl = new StructDecl( "_tuple_type_" + mangleName );
                        decl->set_body( true );
                        int cnt = 0;
                        for ( Type * t : *newType ) {
                                decl->get_members().push_back( new ObjectDecl( "field_"+std::to_string(++cnt), DeclarationNode::NoStorageClass, LinkageSpec::C, nullptr, t->clone(), nullptr ) );
                        }
                        typeMap[mangleName] = decl;
                        addDeclaration( decl );
                }
                Type::Qualifiers qualifiers = newType->get_qualifiers();
                delete newType;
                return new StructInstType( qualifiers, typeMap[mangleName] );
        }

        Expression * TupleIndexExpander::mutate( TupleIndexExpr * tupleExpr ) {
                Expression * tuple = maybeMutate( tupleExpr->get_tuple(), *this );
                assert( tuple );
                tupleExpr->set_tuple( nullptr );
                unsigned int idx = tupleExpr->get_index();
                delete tupleExpr;

                StructInstType * type = safe_dynamic_cast< StructInstType * >( tuple->get_result() );
                StructDecl * structDecl = type->get_baseStruct();
                assert( structDecl->get_members().size() > idx );
                Declaration * member = *std::next(structDecl->get_members().begin(), idx);
                return new MemberExpr( safe_dynamic_cast< DeclarationWithType * >( member ), tuple );
        }

        Expression * TupleExprExpander::mutate( TupleExpr * tupleExpr ) {
                assert( tupleExpr->get_result() );
                std::list< Initializer * > inits;
                for ( Expression * expr : tupleExpr->get_exprs() ) {
                        inits.push_back( new SingleInit( expr ) );
                }
                return new CompoundLiteralExpr( tupleExpr->get_result(), new ListInit( inits ) );
        }

        TupleType * makeTupleType( const std::list< Expression * > & exprs ) {
                TupleType *tupleType = new TupleType( Type::Qualifiers(true, true, true, true, true, false) );
                Type::Qualifiers &qualifiers = tupleType->get_qualifiers();
                for ( Expression * expr : exprs ) {
                        assert( expr->get_result() );
                        Type * type = expr->get_result()->clone();
                        tupleType->get_types().push_back( type );
                        qualifiers &= type->get_qualifiers();
                } // for
                return tupleType;
        }
} // namespace Tuples

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// compile-command: "make install" //
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