Changes in src/InitTweak/RemoveInit.cc [cf16f94:5b2f5bb]

File:

• src/InitTweak/RemoveInit.cc (modified) (8 diffs)

src/InitTweak/RemoveInit.cc

@@ -5 +5 @@
 // file "LICENCE" distributed with Cforall.
 //
-// RemoveInit.cc -- 
+// RemoveInit.cc --
 //
 // Author           : Rob Schluntz
 // Created On       : Mon May 18 07:44:20 2015
-// Last Modified By : Peter A. Buhr
-// Last Modified On : Tue Dec 15 15:37:26 2015
-// Update Count     : 15
-//
-
+// Last Modified By : Rob Schluntz
+// Last Modified On : Wed Mar 30 15:45:12 2016
+// Update Count     : 166
+//
+
+#include <stack>
+#include <list>
 #include "RemoveInit.h"
 #include "SynTree/Declaration.h"
@@ -21 +23 @@
 #include "SynTree/Initializer.h"
 #include "SynTree/Mutator.h"
+#include "SymTab/Autogen.h"
+#include "GenPoly/PolyMutator.h"
 
 namespace InitTweak {
         namespace {
                 const std::list<Label> noLabels;
-        }
-        
-        class RemoveInit : public Mutator {
+                const std::list<Expression *> noDesignators;
+        }
+
+        class RemoveInit : public GenPoly::PolyMutator {
           public:
+                /// removes and replaces initialization for polymorphic value objects
+                /// with assignment (TODO: constructor) statements.
+                /// also consistently allocates a temporary variable for the return value
+                /// of a function so that anything which the resolver decides can be assigned
+                /// into the return type of a function can be returned.
+                static void removeInitializers( std::list< Declaration * > &translationUnit );
+
                 RemoveInit();
-                virtual ObjectDecl * mutate(ObjectDecl *objDecl);
+                virtual ObjectDecl * mutate( ObjectDecl *objDecl );
                 virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
 
                 virtual Statement * mutate( ReturnStmt * returnStmt );
-                
-                virtual CompoundStmt * mutate(CompoundStmt * compoundStmt);
-                
+
           protected:
-                std::list< Statement* > stmtsToAddBefore;
-                std::list< Statement* > stmtsToAddAfter;
-                void mutateStatementList( std::list< Statement* > &statements );
-
                 std::list<DeclarationWithType*> returnVals;
                 UniqueName tempNamer;
@@ -47 +53 @@
         };
 
-        void tweak( std::list< Declaration * > translationUnit ) {
+        class CtorDtor : public GenPoly::PolyMutator {
+          public:
+                /// create constructor and destructor statements for object declarations.
+                /// Destructors are inserted directly into the code, whereas constructors
+                /// will be added in after the resolver has run so that the initializer expression
+                /// is only removed if a constructor is found
+                static void generateCtorDtor( std::list< Declaration * > &translationUnit );
+
+                CtorDtor() : inFunction( false ) {}
+
+                virtual ObjectDecl * mutate( ObjectDecl * );
+                virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
+                virtual Declaration* mutate( StructDecl *aggregateDecl );
+                virtual Declaration* mutate( UnionDecl *aggregateDecl );
+                virtual Declaration* mutate( EnumDecl *aggregateDecl );
+                virtual Declaration* mutate( ContextDecl *aggregateDecl );
+                virtual TypeDecl* mutate( TypeDecl *typeDecl );
+                virtual Declaration* mutate( TypedefDecl *typeDecl );
+
+          protected:
+                bool inFunction;
+        };
+
+        void tweak( std::list< Declaration * > & translationUnit ) {
+                RemoveInit::removeInitializers( translationUnit );
+                CtorDtor::generateCtorDtor( translationUnit );
+        }
+
+        void RemoveInit::removeInitializers( std::list< Declaration * > & translationUnit ) {
                 RemoveInit remover;
                 mutateAll( translationUnit, remover );
@@ -53 +87 @@
 
         RemoveInit::RemoveInit() : tempNamer( "_retVal" ) {}
-        
-        void RemoveInit::mutateStatementList( std::list< Statement* > &statements ) {
-                for ( std::list< Statement* >::iterator i = statements.begin(); i != statements.end(); ++i ) {
-                        if ( ! stmtsToAddAfter.empty() ) {
-                                statements.splice( i, stmtsToAddAfter );
-                        } // if
-                        *i = (*i)->acceptMutator( *this );
-                        if ( ! stmtsToAddBefore.empty() ) {
-                                statements.splice( i, stmtsToAddBefore );
-                        } // if
-                } // for
-                if ( ! stmtsToAddAfter.empty() ) {
-                        statements.splice( statements.end(), stmtsToAddAfter );
-                } // if
-        }
-
-        CompoundStmt *RemoveInit::mutate(CompoundStmt *compoundStmt) {
-                mutateStatementList( compoundStmt->get_kids() );
-                return compoundStmt;
-        }
 
         // in the case where an object has an initializer and a polymorphic type, insert an assignment immediately after the
@@ -79 +93 @@
                 if (objDecl->get_init() && dynamic_cast<TypeInstType*>(objDecl->get_type())) {
                         if (SingleInit * single = dynamic_cast<SingleInit*>(objDecl->get_init())) {
-                                UntypedExpr *assign = new UntypedExpr( new NameExpr( "?=?" ) );
+                                // xxx this can be more complicated - consider ListInit
+                                UntypedExpr *assign = new UntypedExpr( new NameExpr( "?{}" ) );
                                 assign->get_args().push_back( new AddressExpr (new NameExpr( objDecl->get_name() ) ) );
                                 assign->get_args().push_back( single->get_value()->clone() );
@@ -94 +109 @@
                 // is being returned
                 if ( returnStmt->get_expr() && returnVals.size() == 1 && funcName != "?=?" && ! returnVals.front()->get_type()->get_isLvalue()  ) {
-                        ObjectDecl *newObj = new ObjectDecl( tempNamer.newName(), DeclarationNode::NoStorageClass, LinkageSpec::C, 0, returnVals.front()->get_type()->clone(), 0 );
-                        stmtsToAddBefore.push_back( new DeclStmt( noLabels, newObj ) );
-                        
-                        UntypedExpr *assign = new UntypedExpr( new NameExpr( "?=?" ) );
-                        assign->get_args().push_back( new AddressExpr (new NameExpr( newObj->get_name() ) ) );
-                        assign->get_args().push_back( returnStmt->get_expr() );
-                        stmtsToAddBefore.push_back(new ExprStmt(noLabels, assign));
+                        // ensure return value is not destructed by explicitly creating
+                        // an empty SingleInit node wherein maybeConstruct is false
+                        ObjectDecl *newObj = new ObjectDecl( tempNamer.newName(), DeclarationNode::NoStorageClass, LinkageSpec::C, 0, returnVals.front()->get_type()->clone(), new ListInit( std::list<Initializer*>(), noDesignators, false ) );
+                        stmtsToAdd.push_back( new DeclStmt( noLabels, newObj ) );
+
+                        // and explicitly create the constructor expression separately
+                        UntypedExpr *construct = new UntypedExpr( new NameExpr( "?{}" ) );
+                        construct->get_args().push_back( new AddressExpr (new NameExpr( newObj->get_name() ) ) );
+                        construct->get_args().push_back( returnStmt->get_expr() );
+                        stmtsToAdd.push_back(new ExprStmt(noLabels, construct));
 
                         returnStmt->set_expr( new VariableExpr( newObj ) );
@@ -110 +128 @@
                 std::list<DeclarationWithType*> oldReturnVals = returnVals;
                 std::string oldFuncName = funcName;
-                
+
                 FunctionType * type = functionDecl->get_functionType();
                 returnVals = type->get_returnVals();
@@ -119 +137 @@
                 return decl;
         }
+
+
+        void CtorDtor::generateCtorDtor( std::list< Declaration * > & translationUnit ) {
+                CtorDtor ctordtor;
+                mutateAll( translationUnit, ctordtor );
+        }
+
+        namespace {
+                bool tryConstruct( ObjectDecl * objDecl ) {
+                        // xxx - handle designations
+                        return ! LinkageSpec::isBuiltin( objDecl->get_linkage() ) &&
+                                (objDecl->get_init() == NULL ||
+                                ( objDecl->get_init() != NULL && objDecl->get_init()->get_maybeConstructed() ));
+                }
+
+                Expression * makeCtorDtorExpr( std::string name, ObjectDecl * objDecl, std::list< Expression * > args ) {
+                        UntypedExpr * expr = new UntypedExpr( new NameExpr( name ) );
+                        expr->get_args().push_back( new AddressExpr( new VariableExpr( objDecl ) ) );
+                        expr->get_args().splice( expr->get_args().end(), args );
+                        return expr;
+                }
+
+                class InitExpander : public Visitor {
+                  public:
+                  InitExpander() {}
+                  // ~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;
+                }
+        }
+
+        ObjectDecl * CtorDtor::mutate( ObjectDecl * objDecl ) {
+                // hands off if designated or if @=
+                if ( tryConstruct( objDecl ) ) {
+                        if ( inFunction ) {
+                                if ( ArrayType * at = dynamic_cast< ArrayType * >( objDecl->get_type() ) ) {
+                                        // call into makeArrayFunction from validate.cc to generate calls to ctor/dtor for each element of array
+                                        // TODO: walk initializer and generate appropriate copy ctor if element has initializer
+                                        std::list< Statement * > ctor;
+                                        std::list< Statement * > dtor;
+
+                                        SymTab::makeArrayFunction( NULL, new VariableExpr( objDecl ), at, "?{}", back_inserter( ctor ) );
+                                        SymTab::makeArrayFunction( NULL, new VariableExpr( objDecl ), at, "^?{}", front_inserter( dtor ), false );
+
+                                        // Currently makeArrayFunction produces a single Statement - a CompoundStmt
+                                        // which  wraps everything that needs to happen. As such, it's technically
+                                        // possible to use a Statement ** in the above calls, but this is inherently
+                                        // unsafe, so instead we take the slightly less efficient route, but will be
+                                        // immediately informed if somehow the above assumption is broken. In this case,
+                                        // we could always wrap the list of statements at this point with a CompoundStmt,
+                                        // but it seems reasonable at the moment for this to be done by makeArrayFunction
+                                        // itself
+                                        assert( ctor.size() == 1 );
+                                        assert( dtor.size() == 1 );
+
+                                        objDecl->set_init( new ConstructorInit( ctor.front(), dtor.front(), objDecl->get_init() ) );
+                                } else {
+                                        // it's sufficient to attempt to call the ctor/dtor for the given object and its initializer
+                                        Expression * ctor = makeCtorDtorExpr( "?{}", objDecl, makeInitList( objDecl->get_init() ) );
+                                        Expression * dtor = makeCtorDtorExpr( "^?{}", objDecl, std::list< Expression * >() );
+
+                                        // need to remember init expression, in case no ctors exist
+                                        // if ctor does exist, want to use ctor expression instead of init
+                                        // push this decision to the resolver
+                                        ExprStmt * ctorStmt = new ExprStmt( noLabels, ctor );
+                                        ExprStmt * dtorStmt = new ExprStmt( noLabels, dtor );
+                                        objDecl->set_init( new ConstructorInit( ctorStmt, dtorStmt, objDecl->get_init() ) );
+                                }
+                        } else {
+                                // xxx - find a way to construct/destruct globals
+                                // hack: implicit "static" initialization routine for each struct type? or something similar?
+                                // --ties into module system
+                                // this can be done by mangling main and replacing it with our own main which calls each
+                                // module initialization routine in some decided order (order given in link command?)
+                                // and finally calls mangled main
+                        }
+                }
+                return objDecl;
+        }
+
+        DeclarationWithType * CtorDtor::mutate( FunctionDecl *functionDecl ) {
+                // parameters should not be constructed and destructed, so don't mutate FunctionType
+                bool oldInFunc = inFunction;
+                mutateAll( functionDecl->get_oldDecls(), *this );
+                inFunction = true;
+                functionDecl->set_statements( maybeMutate( functionDecl->get_statements(), *this ) );
+                inFunction = oldInFunc;
+                return functionDecl;
+        }
+
+        // should not traverse into any of these declarations to find objects
+        // that need to be constructed or destructed
+        Declaration* CtorDtor::mutate( StructDecl *aggregateDecl ) { return aggregateDecl; }
+        Declaration* CtorDtor::mutate( UnionDecl *aggregateDecl ) { return aggregateDecl; }
+        Declaration* CtorDtor::mutate( EnumDecl *aggregateDecl ) { return aggregateDecl; }
+        Declaration* CtorDtor::mutate( ContextDecl *aggregateDecl ) { return aggregateDecl; }
+        TypeDecl* CtorDtor::mutate( TypeDecl *typeDecl ) { return typeDecl; }
+        Declaration* CtorDtor::mutate( TypedefDecl *typeDecl ) { return typeDecl; }
+
 } // namespace InitTweak