Changeset c331406 for src/InitTweak

Timestamp:

Aug 5, 2016, 11:03:04 AM (10 years ago)

Author:

Aaron Moss <a3moss@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, ctor, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, memory, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, stuck-waitfor-destruct, with_gc

Children:

a2f920f

Parents:

5070fe4 (diff), 1b0020a (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge changes from master

Location:

src/InitTweak

Files:

• FixGlobalInit.cc (modified) (3 diffs)
• FixInit.cc (modified) (11 diffs)
• FixInit.h (modified) (1 diff)
• GenInit.cc (modified) (5 diffs)
• InitTweak.cc (modified) (7 diffs)
• InitTweak.h (modified) (1 diff)

src/InitTweak/FixGlobalInit.cc

@@ -46 +46 @@
                 FunctionDecl * destroyFunction;
         };
-
-        class ConstExprChecker : public Visitor {
-        public:
-                ConstExprChecker() : isConstExpr( true ) {}
-
-                virtual void visit( ApplicationExpr *applicationExpr ) { isConstExpr = false; }
-                virtual void visit( UntypedExpr *untypedExpr ) { isConstExpr = false; }
-                virtual void visit( NameExpr *nameExpr ) { isConstExpr = false; }
-                virtual void visit( CastExpr *castExpr ) { isConstExpr = false; }
-                virtual void visit( LabelAddressExpr *labAddressExpr ) { isConstExpr = false; }
-                virtual void visit( UntypedMemberExpr *memberExpr ) { isConstExpr = false; }
-                virtual void visit( MemberExpr *memberExpr ) { isConstExpr = false; }
-                virtual void visit( VariableExpr *variableExpr ) { isConstExpr = false; }
-                virtual void visit( ConstantExpr *constantExpr ) { /* bottom out */ }
-                // these might be okay?
-                // virtual void visit( SizeofExpr *sizeofExpr );
-                // virtual void visit( AlignofExpr *alignofExpr );
-                // virtual void visit( UntypedOffsetofExpr *offsetofExpr );
-                // virtual void visit( OffsetofExpr *offsetofExpr );
-                // virtual void visit( OffsetPackExpr *offsetPackExpr );
-                // virtual void visit( AttrExpr *attrExpr );
-                // virtual void visit( CommaExpr *commaExpr );
-                // virtual void visit( LogicalExpr *logicalExpr );
-                // virtual void visit( ConditionalExpr *conditionalExpr );
-                virtual void visit( TupleExpr *tupleExpr ) { isConstExpr = false; }
-                virtual void visit( SolvedTupleExpr *tupleExpr ) { isConstExpr = false; }
-                virtual void visit( TypeExpr *typeExpr ) { isConstExpr = false; }
-                virtual void visit( AsmExpr *asmExpr ) { isConstExpr = false; }
-                virtual void visit( UntypedValofExpr *valofExpr ) { isConstExpr = false; }
-                virtual void visit( CompoundLiteralExpr *compLitExpr ) { isConstExpr = false; }
-
-                bool isConstExpr;
-        };
-
-        bool isConstExpr( Initializer * init ) {
-                if ( init ) {
-                        ConstExprChecker checker;
-                        init->accept( checker );
-                        return checker.isConstExpr;
-                } // if
-                // for all intents and purposes, no initializer means const expr
-                return true;
-        }
 
         void fixGlobalInit( std::list< Declaration * > & translationUnit, const std::string & name, bool inLibrary ) {
@@ -140 +97 @@
                 std::list< Statement * > & destroyStatements = destroyFunction->get_statements()->get_kids();
 
-                if ( ! tryConstruct( objDecl ) ) return; // don't construct @= or designated objects
-                if ( objDecl->get_storageClass() == DeclarationNode::Extern ) return;
                 // C allows you to initialize objects with constant expressions
                 // xxx - this is an optimization. Need to first resolve constructors before we decide
@@ -147 +102 @@
                 // if ( isConstExpr( objDecl->get_init() ) ) return;
 
-                if ( dynamic_cast< ArrayType * > ( objDecl->get_type() ) ) {
-                        // xxx - initialize each element of the array
-                } else {
-                        // steal initializer from object and attach it to a new temporary
-                        ObjectDecl *newObj = new ObjectDecl( tempNamer.newName(), DeclarationNode::NoStorageClass, LinkageSpec::C, 0, objDecl->get_type()->clone(), objDecl->get_init() );
-                        objDecl->set_init( NULL );
-                        initStatements.push_back( new DeclStmt( noLabels, newObj ) );
+                if ( ConstructorInit * ctorInit = dynamic_cast< ConstructorInit * >( objDecl->get_init() ) ) {
+                        // a decision should have been made by the resolver, so ctor and init are not both non-NULL
+                        assert( ! ctorInit->get_ctor() || ! ctorInit->get_init() );
 
-                        // copy construct objDecl using temporary
-                        UntypedExpr * init = new UntypedExpr( new NameExpr( "?{}" ) );
-                        init->get_args().push_back( new AddressExpr( new VariableExpr( objDecl ) ) );
-                        init->get_args().push_back( new VariableExpr( newObj ) );
-                        initStatements.push_back( new ImplicitCtorDtorStmt( new ExprStmt( noLabels, init ) ) );
-
-                        // add destructor calls to global destroy function
-                        UntypedExpr * destroy = new UntypedExpr( new NameExpr( "^?{}" ) );
-                        destroy->get_args().push_back( new AddressExpr( new VariableExpr( objDecl ) ) );
-                        destroyStatements.push_front( new ImplicitCtorDtorStmt( new ExprStmt( noLabels, destroy ) ) );
+                        Statement * dtor = ctorInit->get_dtor();
+                        if ( dtor && ! isIntrinsicSingleArgCallStmt( dtor ) ) {
+                                // don't need to call intrinsic dtor, because it does nothing, but
+                                // non-intrinsic dtors must be called
+                                destroyStatements.push_front( dtor );
+                                ctorInit->set_dtor( NULL );
+                        } // if
+                        if ( Statement * ctor = ctorInit->get_ctor() ) {
+                                initStatements.push_back( ctor );
+                                objDecl->set_init( NULL );
+                                ctorInit->set_ctor( NULL );
+                        } else if ( Initializer * init = ctorInit->get_init() ) {
+                                objDecl->set_init( init );
+                                ctorInit->set_init( NULL );
+                        } else {
+                                // no constructor and no initializer, which is okay
+                                objDecl->set_init( NULL );
+                        } // if
+                        delete ctorInit;
                 } // if
         }

src/InitTweak/FixInit.cc

@@ -18 +18 @@
 #include <iterator>
 #include <algorithm>
+#include "InitTweak.h"
 #include "FixInit.h"
-#include "InitTweak.h"
+#include "FixGlobalInit.h"
 #include "ResolvExpr/Resolver.h"
 #include "ResolvExpr/typeops.h"
@@ -25 +26 @@
 #include "SynTree/Type.h"
 #include "SynTree/Expression.h"
+#include "SynTree/Attribute.h"
 #include "SynTree/Statement.h"
 #include "SynTree/Initializer.h"
@@ -83 +85 @@
                 };
 
+                // debug
                 struct printSet {
                         typedef ObjDeclCollector::ObjectSet ObjectSet;
@@ -159 +162 @@
 
                         virtual DeclarationWithType * mutate( ObjectDecl *objDecl );
+
+                        std::list< Declaration * > staticDtorDecls;
                 };
 
@@ -171 +176 @@
         } // namespace
 
-        void fix( std::list< Declaration * > & translationUnit ) {
+        void fix( std::list< Declaration * > & translationUnit, const std::string & filename, bool inLibrary ) {
+                // fixes ConstructorInit for global variables. should happen before fixInitializers.
+                InitTweak::fixGlobalInit( translationUnit, filename, inLibrary );
+
                 InsertImplicitCalls::insert( translationUnit );
                 ResolveCopyCtors::resolveImplicitCalls( translationUnit );
@@ -194 +202 @@
                 void FixInit::fixInitializers( std::list< Declaration * > & translationUnit ) {
                         FixInit fixer;
-                        mutateAll( translationUnit, fixer );
+
+                        // can't use mutateAll, because need to insert declarations at top-level
+                        // can't use DeclMutator, because sometimes need to insert IfStmt, etc.
+                        SemanticError errors;
+                        for ( std::list< Declaration * >::iterator i = translationUnit.begin(); i != translationUnit.end(); ++i ) {
+                                try {
+                                        *i = maybeMutate( *i, fixer );
+                                        translationUnit.splice( i, fixer.staticDtorDecls );
+                                } catch( SemanticError &e ) {
+                                        errors.append( e );
+                                } // try
+                        } // for
+                        if ( ! errors.isEmpty() ) {
+                                throw errors;
+                        } // if
                 }
 
@@ -422 +444 @@
                                 if ( Statement * ctor = ctorInit->get_ctor() ) {
                                         if ( objDecl->get_storageClass() == DeclarationNode::Static ) {
+                                                // originally wanted to take advantage of gcc nested functions, but
+                                                // we get memory errors with this approach. To remedy this, the static
+                                                // variable is hoisted when the destructor needs to be called.
+                                                //
                                                 // generate:
-                                                // static bool __objName_uninitialized = true;
-                                                // if (__objName_uninitialized) {
-                                                //   __ctor(__objName);
-                                                //   void dtor_atexit() {
-                                                //     __dtor(__objName);
+                                                // static T __objName_static_varN;
+                                                // void __objName_dtor_atexitN() {
+                                                //   __dtor__...;
+                                                // }
+                                                // int f(...) {
+                                                //   ...
+                                                //   static bool __objName_uninitialized = true;
+                                                //   if (__objName_uninitialized) {
+                                                //     __ctor(__objName);
+                                                //     __objName_uninitialized = false;
+                                                //     atexit(__objName_dtor_atexitN);
                                                 //   }
-                                                //   on_exit(dtorOnExit, &__objName);
-                                                //   __objName_uninitialized = false;
+                                                //   ...
                                                 // }
 
-                                                // generate first line
+                                                static UniqueName dtorCallerNamer( "_dtor_atexit" );
+
+                                                // static bool __objName_uninitialized = true
                                                 BasicType * boolType = new BasicType( Type::Qualifiers(), BasicType::Bool );
                                                 SingleInit * boolInitExpr = new SingleInit( new ConstantExpr( Constant( boolType->clone(), "1" ) ), noDesignators );
@@ -439 +472 @@
                                                 isUninitializedVar->fixUniqueId();
 
-                                                // void dtor_atexit(...) {...}
-                                                FunctionDecl * dtorCaller = new FunctionDecl( objDecl->get_mangleName() + "_dtor_atexit", DeclarationNode::NoStorageClass, LinkageSpec::C, new FunctionType( Type::Qualifiers(), false ), new CompoundStmt( noLabels ), false, false );
-                                                dtorCaller->fixUniqueId();
-                                                dtorCaller->get_statements()->get_kids().push_back( ctorInit->get_dtor()->clone() );
-
-                                                // on_exit(dtor_atexit);
-                                                UntypedExpr * callAtexit = new UntypedExpr( new NameExpr( "atexit" ) );
-                                                callAtexit->get_args().push_back( new VariableExpr( dtorCaller ) );
-
                                                 // __objName_uninitialized = false;
                                                 UntypedExpr * setTrue = new UntypedExpr( new NameExpr( "?=?" ) );
@@ -457 +481 @@
                                                 std::list< Statement * > & body = initStmts->get_kids();
                                                 body.push_back( ctor );
-                                                body.push_back( new DeclStmt( noLabels, dtorCaller ) );
-                                                body.push_back( new ExprStmt( noLabels, callAtexit ) );
                                                 body.push_back( new ExprStmt( noLabels, setTrue ) );
 
@@ -465 +487 @@
                                                 stmtsToAddAfter.push_back( new DeclStmt( noLabels, isUninitializedVar ) );
                                                 stmtsToAddAfter.push_back( ifStmt );
+
+                                                if ( ctorInit->get_dtor() ) {
+                                                        // if the object has a non-trivial destructor, have to
+                                                        // hoist it and the object into the global space and
+                                                        // call the destructor function with atexit.
+
+                                                        Statement * dtorStmt = ctorInit->get_dtor()->clone();
+
+                                                        // void __objName_dtor_atexitN(...) {...}
+                                                        FunctionDecl * dtorCaller = new FunctionDecl( objDecl->get_mangleName() + dtorCallerNamer.newName(), DeclarationNode::Static, LinkageSpec::C, new FunctionType( Type::Qualifiers(), false ), new CompoundStmt( noLabels ), false, false );
+                                                        dtorCaller->fixUniqueId();
+                                                        dtorCaller->get_statements()->get_kids().push_back( dtorStmt );
+
+                                                        // atexit(dtor_atexit);
+                                                        UntypedExpr * callAtexit = new UntypedExpr( new NameExpr( "atexit" ) );
+                                                        callAtexit->get_args().push_back( new VariableExpr( dtorCaller ) );
+
+                                                        body.push_back( new ExprStmt( noLabels, callAtexit ) );
+
+                                                        // hoist variable and dtor caller decls to list of decls that will be added into global scope
+                                                        staticDtorDecls.push_back( objDecl );
+                                                        staticDtorDecls.push_back( dtorCaller );
+
+                                                        // need to rename object uniquely since it now appears
+                                                        // at global scope and there could be multiple function-scoped
+                                                        // static variables with the same name in different functions.
+                                                        static UniqueName staticNamer( "_static_var" );
+                                                        objDecl->set_mangleName( objDecl->get_mangleName() + staticNamer.newName() );
+
+                                                        objDecl->set_init( NULL );
+                                                        ctorInit->set_ctor( NULL );
+                                                        delete ctorInit;
+
+                                                        // xxx - temporary hack: need to return a declaration, but want to hoist the current object out of this scope
+                                                        // create a new object which is never used
+                                                        static UniqueName dummyNamer( "_dummy" );
+                                                        ObjectDecl * dummy = new ObjectDecl( dummyNamer.newName(), DeclarationNode::Static, LinkageSpec::Cforall, 0, new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) ), 0, std::list< Attribute * >{ new Attribute("unused") } );
+                                                        return dummy;
+                                                }
                                         } else {
                                                 stmtsToAddAfter.push_back( ctor );
@@ -524 +585 @@
                                         assert( ! ctorInit->get_ctor() || ! ctorInit->get_init() );
                                         Statement * dtor = ctorInit->get_dtor();
-                                        if ( dtor && ! isInstrinsicSingleArgCallStmt( dtor ) ) {
+                                        if ( dtor && ! isIntrinsicSingleArgCallStmt( dtor ) ) {
                                                 // don't need to call intrinsic dtor, because it does nothing, but
                                                 // non-intrinsic dtors must be called

src/InitTweak/FixInit.h

@@ -27 +27 @@
   /// replace constructor initializers with expression statements
   /// and unwrap basic C-style initializers
-        void fix( std::list< Declaration * > & translationUnit );
+        void fix( std::list< Declaration * > & translationUnit, const std::string & name, bool inLibrary );
 } // namespace
 

src/InitTweak/GenInit.cc

@@ -26 +26 @@
 #include "SymTab/Autogen.h"
 #include "GenPoly/PolyMutator.h"
+#include "GenPoly/DeclMutator.h"
 
 namespace InitTweak {
@@ -55 +56 @@
           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
+                /// the actual call statements will be added in after the resolver has run
+                /// so that the initializer expression is only removed if a constructor is found
+                /// and the same destructor call is inserted in all of the appropriate locations.
                 static void generateCtorDtor( std::list< Declaration * > &translationUnit );
-
-                CtorDtor() : inFunction( false ) {}
 
                 virtual DeclarationWithType * 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( TraitDecl *aggregateDecl );
-                virtual TypeDecl* mutate( TypeDecl *typeDecl );
-                virtual Declaration* mutate( TypedefDecl *typeDecl );
-
-                virtual Type * mutate( FunctionType *funcType );
+                // should not traverse into any of these declarations to find objects
+                // that need to be constructed or destructed
+                virtual Declaration* mutate( StructDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( UnionDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( EnumDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( TraitDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual TypeDecl* mutate( TypeDecl *typeDecl ) { return typeDecl; }
+                virtual Declaration* mutate( TypedefDecl *typeDecl ) { return typeDecl; }
+
+                virtual Type * mutate( FunctionType *funcType ) { return funcType; }
 
           protected:
-                bool inFunction;
+        };
+
+        class HoistArrayDimension : public GenPoly::DeclMutator {
+          public:
+                typedef GenPoly::DeclMutator Parent;
+
+                /// hoist dimension from array types in object declaration so that it uses a single
+                /// const variable of type size_t, so that side effecting array dimensions are only
+                /// computed once.
+                static void hoistArrayDimension( std::list< Declaration * > & translationUnit );
+
+          private:
+                virtual DeclarationWithType * mutate( ObjectDecl * objectDecl );
+                virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
+                // should not traverse into any of these declarations to find objects
+                // that need to be constructed or destructed
+                virtual Declaration* mutate( StructDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( UnionDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( EnumDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual Declaration* mutate( TraitDecl *aggregateDecl ) { return aggregateDecl; }
+                virtual TypeDecl* mutate( TypeDecl *typeDecl ) { return typeDecl; }
+                virtual Declaration* mutate( TypedefDecl *typeDecl ) { return typeDecl; }
+
+                virtual Type* mutate( FunctionType *funcType ) { return funcType; }
+
+                void hoist( Type * type );
+
+                DeclarationNode::StorageClass storageclass = DeclarationNode::NoStorageClass;
+                bool inFunction = false;
         };
 
         void genInit( std::list< Declaration * > & translationUnit ) {
                 ReturnFixer::makeReturnTemp( translationUnit );
+                HoistArrayDimension::hoistArrayDimension( translationUnit );
                 CtorDtor::generateCtorDtor( translationUnit );
         }
@@ -124 +154 @@
         }
 
+        // precompute array dimension expression, because constructor generation may duplicate it,
+        // which would be incorrect if it is a side-effecting computation.
+        void HoistArrayDimension::hoistArrayDimension( std::list< Declaration * > & translationUnit ) {
+                HoistArrayDimension hoister;
+                hoister.mutateDeclarationList( translationUnit );
+        }
+
+        DeclarationWithType * HoistArrayDimension::mutate( ObjectDecl * objectDecl ) {
+                storageclass = objectDecl->get_storageClass();
+                DeclarationWithType * temp = Parent::mutate( objectDecl );
+                hoist( objectDecl->get_type() );
+                storageclass = DeclarationNode::NoStorageClass;
+                return temp;
+        }
+
+        void HoistArrayDimension::hoist( Type * type ) {
+                // if in function, generate const size_t var
+                static UniqueName dimensionName( "_array_dim" );
+
+                // C doesn't allow variable sized arrays at global scope or for static variables,
+                // so don't hoist dimension.
+                if ( ! inFunction ) return;
+                if ( storageclass == DeclarationNode::Static ) return;
+
+                if ( ArrayType * arrayType = dynamic_cast< ArrayType * >( type ) ) {
+                        if ( ! arrayType->get_dimension() ) return; // xxx - recursive call to hoist?
+
+                        // don't need to hoist dimension if it's a constexpr - only need to if there's potential
+                        // for side effects.
+                        if ( isConstExpr( arrayType->get_dimension() ) ) return;
+
+                        ObjectDecl * arrayDimension = new ObjectDecl( dimensionName.newName(), storageclass, LinkageSpec::C, 0, SymTab::SizeType->clone(), new SingleInit( arrayType->get_dimension() ) );
+                        arrayDimension->get_type()->set_isConst( true );
+
+                        arrayType->set_dimension( new VariableExpr( arrayDimension ) );
+                        addDeclaration( arrayDimension );
+
+                        hoist( arrayType->get_base() );
+                        return;
+                }
+        }
+
+        DeclarationWithType * HoistArrayDimension::mutate( FunctionDecl *functionDecl ) {
+                bool oldInFunc = inFunction;
+                inFunction = true;
+                DeclarationWithType * decl = Parent::mutate( functionDecl );
+                inFunction = oldInFunc;
+                return decl;
+        }
 
         void CtorDtor::generateCtorDtor( std::list< Declaration * > & translationUnit ) {
@@ -130 +209 @@
         }
 
-        namespace {
-                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;
-                }
-        }
-
         DeclarationWithType * CtorDtor::mutate( ObjectDecl * objDecl ) {
-                // hands off if designated or if @=
+                // hands off if designated, if @=, or if extern
                 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< Expression * > args = makeInitList( objDecl->get_init() );
-                                        if ( args.empty() ) {
-                                                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 && dynamic_cast< ImplicitCtorDtorStmt * >( ctor.front() ) );
-                                                assert( dtor.size() == 1 && dynamic_cast< ImplicitCtorDtorStmt * >( dtor.front() ) );
-                                                objDecl->set_init( new ConstructorInit( ctor.front(), dtor.front(), objDecl->get_init() ) );
-                                        } else {
-                                                // array came with an initializer list: initialize each element
-                                                // may have more initializers than elements in the array - need to check at each index that
-                                                // we haven't exceeded size. This requires precomputing the size because it might be a side-effecting
-                                                // computation.
-                                                // may have fewer initializers than eleemnts in the array - need to default construct
-                                                // remaining elements.
-                                                // might be able to merge this with the case above.
-                                        }
-                                } 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( new ImplicitCtorDtorStmt( ctorStmt ), new ImplicitCtorDtorStmt( dtorStmt ), objDecl->get_init() ) );
-                                }
+                        // call into genImplicitCall from Autogen.h to generate calls to ctor/dtor
+                        // for each constructable object
+                        std::list< Statement * > ctor;
+                        std::list< Statement * > dtor;
+
+                        InitExpander srcParam( objDecl->get_init() );
+                        InitExpander nullParam( (Initializer *)NULL );
+                        SymTab::genImplicitCall( srcParam, new VariableExpr( objDecl ), "?{}", back_inserter( ctor ), objDecl );
+                        SymTab::genImplicitCall( nullParam, new VariableExpr( objDecl ), "^?{}", front_inserter( dtor ), objDecl, false );
+
+                        // Currently genImplicitCall 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 genImplicitCall
+                        // itself. It is possible that genImplicitCall produces no statements (e.g. if
+                        // an array type does not have a dimension). In this case, it's fine to ignore
+                        // the object for the purposes of construction.
+                        assert( ctor.size() == dtor.size() && ctor.size() <= 1 );
+                        if ( ctor.size() == 1 ) {
+                                // 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
+                                assert( dynamic_cast< ImplicitCtorDtorStmt * > ( ctor.front() ) && dynamic_cast< ImplicitCtorDtorStmt * > ( dtor.front() ) );
+                                objDecl->set_init( new ConstructorInit( ctor.front(), dtor.front(), objDecl->get_init() ) );
                         }
                 }
@@ -193 +246 @@
         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( TraitDecl *aggregateDecl ) { return aggregateDecl; }
-        TypeDecl* CtorDtor::mutate( TypeDecl *typeDecl ) { return typeDecl; }
-        Declaration* CtorDtor::mutate( TypedefDecl *typeDecl ) { return typeDecl; }
-        Type* CtorDtor::mutate( FunctionType *funcType ) { return funcType; }
-
 } // namespace InitTweak
 

src/InitTweak/InitTweak.cc

@@ +1 @@
+#include <algorithm>
 #include "InitTweak.h"
 #include "SynTree/Visitor.h"
@@ -4 +5 @@
 #include "SynTree/Initializer.h"
 #include "SynTree/Expression.h"
+#include "SynTree/Attribute.h"
 #include "GenPoly/GenPoly.h"
 
@@ -20 +22 @@
                 };
 
-                class InitExpander : public Visitor {
+                class InitFlattener : public Visitor {
                         public:
-                        InitExpander() {}
                         virtual void visit( SingleInit * singleInit );
                         virtual void visit( ListInit * listInit );
@@ -28 +29 @@
                 };
 
-                void InitExpander::visit( SingleInit * singleInit ) {
+                void InitFlattener::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 ) {
+                void InitFlattener::visit( ListInit * listInit ) {
+                        // flatten nested list inits
+                        std::list<Initializer*>::iterator it = listInit->begin();
+                        for ( ; it != listInit->end(); ++it ) {
                                 (*it)->accept( *this );
                         }
@@ -42 +43 @@
 
         std::list< Expression * > makeInitList( Initializer * init ) {
-                InitExpander expander;
-                maybeAccept( init, expander );
-                return expander.argList;
+                InitFlattener flattener;
+                maybeAccept( init, flattener );
+                return flattener.argList;
         }
 
@@ -53 +54 @@
         }
 
+        class InitExpander::ExpanderImpl {
+        public:
+                virtual std::list< Expression * > next( std::list< Expression * > & indices ) = 0;
+                virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices ) = 0;
+        };
+
+        class InitImpl : public InitExpander::ExpanderImpl {
+        public:
+                InitImpl( Initializer * init ) : init( init ) {}
+
+                virtual std::list< Expression * > next( std::list< Expression * > & indices ) {
+                        // this is wrong, but just a placeholder for now
+                        // if ( ! flattened ) flatten( indices );
+                        // return ! inits.empty() ? makeInitList( inits.front() ) : std::list< Expression * >();
+                        return makeInitList( init );
+                }
+
+                virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices );
+        private:
+                Initializer * init;
+        };
+
+        class ExprImpl : public InitExpander::ExpanderImpl {
+        public:
+                ExprImpl( Expression * expr ) : arg( expr ) {}
+
+                virtual std::list< Expression * > next( std::list< Expression * > & indices ) {
+                        std::list< Expression * > ret;
+                        Expression * expr = maybeClone( arg );
+                        if ( expr ) {
+                                for ( std::list< Expression * >::reverse_iterator it = indices.rbegin(); it != indices.rend(); ++it ) {
+                                        // go through indices and layer on subscript exprs ?[?]
+                                        ++it;
+                                        UntypedExpr * subscriptExpr = new UntypedExpr( new NameExpr( "?[?]") );
+                                        subscriptExpr->get_args().push_back( expr );
+                                        subscriptExpr->get_args().push_back( (*it)->clone() );
+                                        expr = subscriptExpr;
+                                }
+                                ret.push_back( expr );
+                        }
+                        return ret;
+                }
+
+                virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices );
+        private:
+                Expression * arg;
+        };
+
+        InitExpander::InitExpander( Initializer * init ) : expander( new InitImpl( init ) ) {}
+
+        InitExpander::InitExpander( Expression * expr ) : expander( new ExprImpl( expr ) ) {}
+
+        std::list< Expression * > InitExpander::operator*() {
+                return cur;
+        }
+
+        InitExpander & InitExpander::operator++() {
+                cur = expander->next( indices );
+                return *this;
+        }
+
+        // use array indices list to build switch statement
+        void InitExpander::addArrayIndex( Expression * index, Expression * dimension ) {
+                indices.push_back( index );
+                indices.push_back( dimension );
+        }
+
+        void InitExpander::clearArrayIndices() {
+                indices.clear();
+        }
+
+        namespace {
+                /// given index i, dimension d, initializer init, and callExpr f, generates
+                ///   if (i < d) f(..., init)
+                ///   ++i;
+                /// so that only elements within the range of the array are constructed
+                template< typename OutIterator >
+                void buildCallExpr( UntypedExpr * callExpr, Expression * index, Expression * dimension, Initializer * init, OutIterator out ) {
+                        UntypedExpr * cond = new UntypedExpr( new NameExpr( "?<?") );
+                        cond->get_args().push_back( index->clone() );
+                        cond->get_args().push_back( dimension->clone() );
+
+                        std::list< Expression * > args = makeInitList( init );
+                        callExpr->get_args().splice( callExpr->get_args().end(), args );
+
+                        *out++ = new IfStmt( noLabels, cond, new ExprStmt( noLabels, callExpr ), NULL );
+
+                        UntypedExpr * increment = new UntypedExpr( new NameExpr( "++?" ) );
+                        increment->get_args().push_back( new AddressExpr( index->clone() ) );
+                        *out++ = new ExprStmt( noLabels, increment );
+                }
+
+                template< typename OutIterator >
+                void build( UntypedExpr * callExpr, InitExpander::IndexList::iterator idx, InitExpander::IndexList::iterator idxEnd, Initializer * init, OutIterator out ) {
+                        if ( idx == idxEnd ) return;
+                        Expression * index = *idx++;
+                        assert( idx != idxEnd );
+                        Expression * dimension = *idx++;
+
+                        // xxx - may want to eventually issue a warning here if we can detect
+                        // that the number of elements exceeds to dimension of the array
+                        if ( idx == idxEnd ) {
+                                if ( ListInit * listInit = dynamic_cast< ListInit * >( init ) ) {
+                                        for ( Initializer * init : *listInit ) {
+                                                buildCallExpr( callExpr->clone(), index, dimension, init, out );
+                                        }
+                                } else {
+                                        buildCallExpr( callExpr->clone(), index, dimension, init, out );
+                                }
+                        } else {
+                                std::list< Statement * > branches;
+
+                                unsigned long cond = 0;
+                                ListInit * listInit = dynamic_cast< ListInit * >( init );
+                                if ( ! listInit ) {
+                                        // xxx - this shouldn't be an error, but need a way to
+                                        // terminate without creating output, so should catch this error
+                                        throw SemanticError( "unbalanced list initializers" );
+                                }
+
+                                static UniqueName targetLabel( "L__autogen__" );
+                                Label switchLabel( targetLabel.newName(), 0, std::list< Attribute * >{ new Attribute("unused") } );
+                                for ( Initializer * init : *listInit ) {
+                                        Expression * condition;
+                                        // check for designations
+                                        // if ( init-> ) {
+                                                condition = new ConstantExpr( Constant::from_ulong( cond ) );
+                                                ++cond;
+                                        // } else {
+                                        //      condition = // ... take designation
+                                        //      cond = // ... take designation+1
+                                        // }
+                                        std::list< Statement * > stmts;
+                                        build( callExpr, idx, idxEnd, init, back_inserter( stmts ) );
+                                        stmts.push_back( new BranchStmt( noLabels, switchLabel, BranchStmt::Break ) );
+                                        CaseStmt * caseStmt = new CaseStmt( noLabels, condition, stmts );
+                                        branches.push_back( caseStmt );
+                                }
+                                *out++ = new SwitchStmt( noLabels, index->clone(), branches );
+                                *out++ = new NullStmt( std::list<Label>{ switchLabel } );
+                        }
+                }
+        }
+
+        // if array came with an initializer list: initialize each element
+        // may have more initializers than elements in the array - need to check at each index that
+        // we haven't exceeded size.
+        // may have fewer initializers than elements in the array - need to default construct
+        // remaining elements.
+        // To accomplish this, generate switch statement, consuming all of expander's elements
+        Statement * InitImpl::buildListInit( UntypedExpr * dst, std::list< Expression * > & indices ) {
+                if ( ! init ) return NULL;
+                CompoundStmt * block = new CompoundStmt( noLabels );
+                build( dst, indices.begin(), indices.end(), init, back_inserter( block->get_kids() ) );
+                if ( block->get_kids().empty() ) {
+                        delete block;
+                        return NULL;
+                } else {
+                        init = NULL; // init was consumed in creating the list init
+                        return block;
+                }
+        }
+
+        Statement * ExprImpl::buildListInit( UntypedExpr * dst, std::list< Expression * > & indices ) {
+                return NULL;
+        }
+
+        Statement * InitExpander::buildListInit( UntypedExpr * dst ) {
+                return expander->buildListInit( dst, indices );
+        }
+
         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() );
+                        ! isDesignated( objDecl->get_init() )
+                        && objDecl->get_storageClass() != DeclarationNode::Extern;
+        }
+
+        class CallFinder : public Visitor {
+        public:
+                typedef Visitor Parent;
+                CallFinder( const std::list< std::string > & names ) : names( names ) {}
+
+                virtual void visit( ApplicationExpr * appExpr ) {
+                        handleCallExpr( appExpr );
+                }
+
+                virtual void visit( UntypedExpr * untypedExpr ) {
+                        handleCallExpr( untypedExpr );
+                }
+
+                std::list< Expression * > * matches;
+        private:
+                const std::list< std::string > names;
+
+                template< typename CallExpr >
+                void handleCallExpr( CallExpr * expr ) {
+                        Parent::visit( expr );
+                        std::string fname = getFunctionName( expr );
+                        if ( std::find( names.begin(), names.end(), fname ) != names.end() ) {
+                                matches->push_back( expr );
+                        }
+                }
+        };
+
+        void collectCtorDtorCalls( Statement * stmt, std::list< Expression * > & matches ) {
+                static CallFinder finder( std::list< std::string >{ "?{}", "^?{}" } );
+                finder.matches = &matches;
+                maybeAccept( stmt, finder );
         }
 
         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
-                        if( 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() );
-                        } else if ( compoundStmt->get_kids().size() == 1 ) {
-                                // should be the call statement, but in any case there's only one option
-                                return getCtorDtorCall( compoundStmt->get_kids().front() );
-                        } else {
-                                assert( false && "too many statements in compoundStmt for getCtorDtorCall" );
-                        }
-                } 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() );
+                std::list< Expression * > matches;
+                collectCtorDtorCalls( stmt, matches );
+                assert( matches.size() <= 1 );
+                return matches.size() == 1 ? matches.front() : NULL;
+        }
+
+        namespace {
+                VariableExpr * getCalledFunction( ApplicationExpr * appExpr ) {
+                        assert( appExpr );
+                        // xxx - it's possible this can be other things, e.g. MemberExpr, so this is insufficient
+                        return dynamic_cast< VariableExpr * >( appExpr->get_function() );
+                }
+        }
+
+        ApplicationExpr * isIntrinsicCallExpr( Expression * expr ) {
+                ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( expr );
+                if ( ! appExpr ) return NULL;
+                VariableExpr * function = getCalledFunction( appExpr );
                 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;
+                return function->get_var()->get_linkage() == LinkageSpec::Intrinsic ? appExpr : NULL;
+        }
+
+        bool isIntrinsicSingleArgCallStmt( Statement * stmt ) {
+                std::list< Expression * > callExprs;
+                collectCtorDtorCalls( stmt, callExprs );
+                // if ( callExprs.empty() ) return false; // xxx - do I still need this check?
+                return std::all_of( callExprs.begin(), callExprs.end(), []( Expression * callExpr ){
+                        if ( ApplicationExpr * appExpr = isIntrinsicCallExpr( callExpr ) ) {
+                                assert( ! appExpr->get_function()->get_results().empty() );
+                                FunctionType *funcType = GenPoly::getFunctionType( appExpr->get_function()->get_results().front() );
+                                assert( funcType );
+                                return funcType->get_parameters().size() == 1;
+                        }
+                        return false;
+                });
         }
 
@@ -160 +367 @@
                 else return NULL;
         }
+
+        class ConstExprChecker : public Visitor {
+        public:
+                ConstExprChecker() : isConstExpr( true ) {}
+
+                virtual void visit( ApplicationExpr *applicationExpr ) { isConstExpr = false; }
+                virtual void visit( UntypedExpr *untypedExpr ) { isConstExpr = false; }
+                virtual void visit( NameExpr *nameExpr ) { isConstExpr = false; }
+                virtual void visit( CastExpr *castExpr ) { isConstExpr = false; }
+                virtual void visit( LabelAddressExpr *labAddressExpr ) { isConstExpr = false; }
+                virtual void visit( UntypedMemberExpr *memberExpr ) { isConstExpr = false; }
+                virtual void visit( MemberExpr *memberExpr ) { isConstExpr = false; }
+                virtual void visit( VariableExpr *variableExpr ) { isConstExpr = false; }
+                virtual void visit( ConstantExpr *constantExpr ) { /* bottom out */ }
+                // these might be okay?
+                // virtual void visit( SizeofExpr *sizeofExpr );
+                // virtual void visit( AlignofExpr *alignofExpr );
+                // virtual void visit( UntypedOffsetofExpr *offsetofExpr );
+                // virtual void visit( OffsetofExpr *offsetofExpr );
+                // virtual void visit( OffsetPackExpr *offsetPackExpr );
+                // virtual void visit( AttrExpr *attrExpr );
+                // virtual void visit( CommaExpr *commaExpr );
+                // virtual void visit( LogicalExpr *logicalExpr );
+                // virtual void visit( ConditionalExpr *conditionalExpr );
+                virtual void visit( TupleExpr *tupleExpr ) { isConstExpr = false; }
+                virtual void visit( SolvedTupleExpr *tupleExpr ) { isConstExpr = false; }
+                virtual void visit( TypeExpr *typeExpr ) { isConstExpr = false; }
+                virtual void visit( AsmExpr *asmExpr ) { isConstExpr = false; }
+                virtual void visit( UntypedValofExpr *valofExpr ) { isConstExpr = false; }
+                virtual void visit( CompoundLiteralExpr *compLitExpr ) { isConstExpr = false; }
+
+                bool isConstExpr;
+        };
+
+        bool isConstExpr( Expression * expr ) {
+                if ( expr ) {
+                        ConstExprChecker checker;
+                        expr->accept( checker );
+                        return checker.isConstExpr;
+                }
+                return true;
+        }
+
+        bool isConstExpr( Initializer * init ) {
+                if ( init ) {
+                        ConstExprChecker checker;
+                        init->accept( checker );
+                        return checker.isConstExpr;
+                } // if
+                // for all intents and purposes, no initializer means const expr
+                return true;
+        }
+
 }

src/InitTweak/InitTweak.h

@@ -26 +26 @@
 // helper functions for initialization
 namespace InitTweak {
-  /// transform Initializer into an argument list that can be passed to a call expression
-  std::list< Expression * > makeInitList( Initializer * init );
+        /// transform Initializer into an argument list that can be passed to a call expression
+        std::list< Expression * > makeInitList( Initializer * init );
 
-  /// True if the resolver should try to construct objDecl
-  bool tryConstruct( ObjectDecl * objDecl );
+        /// True if the resolver should try to construct objDecl
+        bool tryConstruct( ObjectDecl * objDecl );
 
-  /// True if the Initializer contains designations
-  bool isDesignated( Initializer * init );
+        /// True if the Initializer contains designations
+        bool isDesignated( Initializer * init );
 
-  /// True if stmt is a call statement where the function called is intrinsic and takes one parameter.
-  /// Intended to be used for default ctor/dtor calls, but might have use elsewhere.
-  /// Currently has assertions that make it less than fully general.
-  bool isInstrinsicSingleArgCallStmt( Statement * expr );
+  /// Non-Null if expr is a call expression whose target function is intrinsic
+  ApplicationExpr * isIntrinsicCallExpr( Expression * expr );
 
-  /// get the Ctor/Dtor call expression from a Statement that looks like a generated ctor/dtor call
-  Expression * getCtorDtorCall( Statement * stmt );
+        /// True if stmt is a call statement where the function called is intrinsic and takes one parameter.
+        /// Intended to be used for default ctor/dtor calls, but might have use elsewhere.
+        /// Currently has assertions that make it less than fully general.
+        bool isIntrinsicSingleArgCallStmt( Statement * expr );
 
-  /// returns the name of the function being called
-  std::string getFunctionName( Expression * expr );
+        /// get all Ctor/Dtor call expressions from a Statement
+        void collectCtorDtorCalls( Statement * stmt, std::list< Expression * > & matches );
 
-  /// returns the argument to a call expression in position N indexed from 0
-  Expression *& getCallArg( Expression * callExpr, unsigned int pos );
+        /// get the Ctor/Dtor call expression from a Statement that looks like a generated ctor/dtor call
+        Expression * getCtorDtorCall( Statement * stmt );
 
-  /// returns the base type of a PointerType or ArrayType, else returns NULL
-  Type * getPointerBase( Type * );
+        /// returns the name of the function being called
+        std::string getFunctionName( Expression * expr );
 
-  /// returns the argument if it is a PointerType or ArrayType, else returns NULL
-  Type * isPointerType( Type * );
+        /// returns the argument to a call expression in position N indexed from 0
+        Expression *& getCallArg( Expression * callExpr, unsigned int pos );
+
+        /// returns the base type of a PointerType or ArrayType, else returns NULL
+        Type * getPointerBase( Type * );
+
+        /// returns the argument if it is a PointerType or ArrayType, else returns NULL
+        Type * isPointerType( Type * );
+
+        /// returns true if expr is trivially a compile-time constant
+        bool isConstExpr( Expression * expr );
+        bool isConstExpr( Initializer * init );
+
+        class InitExpander {
+        public:
+                // expand by stepping through init to get each list of arguments
+                InitExpander( Initializer * init );
+
+                // always expand to expr
+                InitExpander( Expression * expr );
+
+                // iterator-like interface
+                std::list< Expression * > operator*();
+                InitExpander & operator++();
+
+                // builds statement which has the same semantics as a C-style list initializer
+                // (for array initializers) using callExpr as the base expression to perform initialization
+                Statement * buildListInit( UntypedExpr * callExpr );
+                void addArrayIndex( Expression * index, Expression * dimension );
+                void clearArrayIndices();
+
+                class ExpanderImpl;
+        private:
+                std::shared_ptr< ExpanderImpl > expander;
+                std::list< Expression * > cur;
+
+                // invariant: list of size 2N (elements come in pairs [index, dimension])
+                typedef std::list< Expression * > IndexList;
+                IndexList indices;
+        };
 } // namespace