source: src/InitTweak/InitTweak.cc @ 4efe4d1

#include "InitTweak.h"
#include "SynTree/Visitor.h"
#include "SynTree/Statement.h"
#include "SynTree/Initializer.h"
#include "SynTree/Expression.h"
#include "GenPoly/GenPoly.h"

namespace InitTweak {
        namespace {
                class HasDesignations : public Visitor {
                public:
                        bool hasDesignations = false;
                        template<typename Init>
                        void handleInit( Init * init ) {
                                if ( ! init->get_designators().empty() ) hasDesignations = true;
                                else Visitor::visit( init );
                        }
                        virtual void visit( SingleInit * singleInit ) { handleInit( singleInit); }
                        virtual void visit( ListInit * listInit ) { handleInit( listInit); }
                };

                class InitExpander : public Visitor {
                        public:
                        InitExpander() {}
                        virtual void visit( SingleInit * singleInit );
                        virtual void visit( ListInit * listInit );
                        std::list< Expression * > argList;
                };

                void InitExpander::visit( SingleInit * singleInit ) {
                        argList.push_back( singleInit->get_value()->clone() );
                }

                void InitExpander::visit( ListInit * listInit ) {
                        // xxx - for now, assume no nested list inits
                        std::list<Initializer*>::iterator it = listInit->begin_initializers();
                        for ( ; it != listInit->end_initializers(); ++it ) {
                                (*it)->accept( *this );
                        }
                }
        }

        std::list< Expression * > makeInitList( Initializer * init ) {
                InitExpander expander;
                maybeAccept( init, expander );
                return expander.argList;
        }

        bool isDesignated( Initializer * init ) {
                HasDesignations finder;
                maybeAccept( init, finder );
                return finder.hasDesignations;
        }

        bool tryConstruct( ObjectDecl * objDecl ) {
                return ! LinkageSpec::isBuiltin( objDecl->get_linkage() ) &&
                        (objDecl->get_init() == NULL ||
                                ( objDecl->get_init() != NULL && objDecl->get_init()->get_maybeConstructed() )) &&
                        ! isDesignated( objDecl->get_init() );
        }

        Expression * getCtorDtorCall( Statement * stmt ) {
                if ( stmt == NULL ) return NULL;
                if ( ExprStmt * exprStmt = dynamic_cast< ExprStmt * >( stmt ) ) {
                        return exprStmt->get_expr();
                } else if ( CompoundStmt * compoundStmt = dynamic_cast< CompoundStmt * >( stmt ) ) {
                        // could also be a compound statement with a loop, in the case of an array
                        assert( compoundStmt->get_kids().size() == 2 ); // loop variable and loop
                        ForStmt * forStmt = dynamic_cast< ForStmt * >( compoundStmt->get_kids().back() );
                        assert( forStmt && forStmt->get_body() );
                        return getCtorDtorCall( forStmt->get_body() );
                } if ( ImplicitCtorDtorStmt * impCtorDtorStmt = dynamic_cast< ImplicitCtorDtorStmt * > ( stmt ) ) {
                        return getCtorDtorCall( impCtorDtorStmt->get_callStmt() );
                } else {
                        // should never get here
                        assert( false && "encountered unknown call statement" );
                }
        }

        bool isInstrinsicSingleArgCallStmt( Statement * stmt ) {
                Expression * callExpr = getCtorDtorCall( stmt );
                if ( ! callExpr ) return false;
                ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( callExpr );
                assert( appExpr );
                VariableExpr * function = dynamic_cast< VariableExpr * >( appExpr->get_function() );
                assert( function );
                // check for Intrinsic only - don't want to remove all overridable ctor/dtors because autogenerated ctor/dtor
                // will call all member dtors, and some members may have a user defined dtor.
                FunctionType * funcType = GenPoly::getFunctionType( function->get_var()->get_type() );
                assert( funcType );
                return function->get_var()->get_linkage() == LinkageSpec::Intrinsic && funcType->get_parameters().size() == 1;
        }

        namespace {
                template<typename CallExpr>
                Expression *& callArg( CallExpr * callExpr, unsigned int pos ) {
                        if ( pos >= callExpr->get_args().size() ) assert( false && "asking for argument that doesn't exist. Return NULL/throw exception?" );
                        for ( Expression *& arg : callExpr->get_args() ) {
                                if ( pos == 0 ) return arg;
                                pos--;
                        }
                        assert( false );
                }
        }

        Expression *& getCallArg( Expression * callExpr, unsigned int pos ) {
                if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( callExpr ) ) {
                        return callArg( appExpr, pos );
                } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * >( callExpr ) ) {
                        return callArg( untypedExpr, pos );
                } else {
                        assert( false && "Unexpected expression type passed to getCallArg" );
                }
        }

        namespace {
                template<typename CallExpr>
                std::string funcName( CallExpr * expr ) {
                        Expression * func = expr->get_function();
                        if ( NameExpr * nameExpr = dynamic_cast< NameExpr * >( func ) ) {
                                return nameExpr->get_name();
                        } else if ( VariableExpr * varExpr = dynamic_cast< VariableExpr * >( func ) ) {
                                return varExpr->get_var()->get_name();
                        } else {
                                assert( false && "Unexpected expression type being called as a function in call expression" );
                        }
                }
        }

        std::string getFunctionName( Expression * expr ) {
                if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( expr ) ) {
                        return funcName( appExpr );
                } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * > ( expr ) ) {
                        return funcName( untypedExpr );
                } else {
                        assert( false && "Unexpected expression type passed to getFunctionName" );
                }
        }

        Type * getPointerBase( Type * type ) {
                if ( PointerType * ptrType = dynamic_cast< PointerType * >( type ) ) {
                        return ptrType->get_base();
                } else if ( ArrayType * arrayType = dynamic_cast< ArrayType * >( type ) ) {
                        return arrayType->get_base();
                } else {
                        return NULL;
                }
        }

        Type * isPointerType( Type * type ) {
                if ( getPointerBase( type ) ) return type;
                else return NULL;
        }
}