// // 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. // // Validate.cc -- // // Author : Richard C. Bilson // Created On : Sun May 17 21:50:04 2015 // Last Modified By : Andrew Beach // Last Modified On : Tue Jul 12 15:00:00 2022 // Update Count : 367 // // The "validate" phase of translation is used to take a syntax tree and convert it into a standard form that aims to be // as regular in structure as possible. Some assumptions can be made regarding the state of the tree after this pass is // complete, including: // // - No nested structure or union definitions; any in the input are "hoisted" to the level of the containing struct or // union. // // - All enumeration constants have type EnumInstType. // // - The type "void" never occurs in lists of function parameter or return types. A function // taking no arguments has no argument types. // // - No context instances exist; they are all replaced by the set of declarations signified by the context, instantiated // by the particular set of type arguments. // // - Every declaration is assigned a unique id. // // - No typedef declarations or instances exist; the actual type is substituted for each instance. // // - Each type, struct, and union definition is followed by an appropriate assignment operator. // // - Each use of a struct or union is connected to a complete definition of that struct or union, even if that // definition occurs later in the input. #include "Validate.h" #include // for assertf, assert #include // for size_t #include // for list #include // for string #include // for unordered_map #include // for pair #include "CodeGen/CodeGenerator.h" // for genName #include "CodeGen/OperatorTable.h" // for isCtorDtor, isCtorDtorAssign #include "ControlStruct/Mutate.h" // for ForExprMutator #include "Common/CodeLocation.h" // for CodeLocation #include "Common/Stats.h" // for Stats::Heap #include "Common/PassVisitor.h" // for PassVisitor, WithDeclsToAdd #include "Common/ScopedMap.h" // for ScopedMap #include "Common/SemanticError.h" // for SemanticError #include "Common/UniqueName.h" // for UniqueName #include "Common/utility.h" // for operator+, cloneAll, deleteAll #include "CompilationState.h" // skip some passes in new-ast build #include "Concurrency/Keywords.h" // for applyKeywords #include "FixFunction.h" // for FixFunction #include "Indexer.h" // for Indexer #include "InitTweak/GenInit.h" // for fixReturnStatements #include "InitTweak/InitTweak.h" // for isCtorDtorAssign #include "ResolvExpr/typeops.h" // for typesCompatible #include "ResolvExpr/Resolver.h" // for findSingleExpression #include "ResolvExpr/ResolveTypeof.h" // for resolveTypeof #include "SymTab/Autogen.h" // for SizeType #include "SymTab/ValidateType.h" // for decayEnumsAndPointers, decayFo... #include "SynTree/LinkageSpec.h" // for C #include "SynTree/Attribute.h" // for noAttributes, Attribute #include "SynTree/Constant.h" // for Constant #include "SynTree/Declaration.h" // for ObjectDecl, DeclarationWithType #include "SynTree/Expression.h" // for CompoundLiteralExpr, Expressio... #include "SynTree/Initializer.h" // for ListInit, Initializer #include "SynTree/Label.h" // for operator==, Label #include "SynTree/Mutator.h" // for Mutator #include "SynTree/Type.h" // for Type, TypeInstType, EnumInstType #include "SynTree/TypeSubstitution.h" // for TypeSubstitution #include "SynTree/Visitor.h" // for Visitor #include "Validate/HandleAttributes.h" // for handleAttributes #include "Validate/FindSpecialDecls.h" // for FindSpecialDecls class CompoundStmt; class ReturnStmt; class SwitchStmt; #define debugPrint( x ) if ( doDebug ) x namespace SymTab { /// hoists declarations that are difficult to hoist while parsing struct HoistTypeDecls final : public WithDeclsToAdd { void previsit( SizeofExpr * ); void previsit( AlignofExpr * ); void previsit( UntypedOffsetofExpr * ); void previsit( CompoundLiteralExpr * ); void handleType( Type * ); }; struct FixQualifiedTypes final : public WithIndexer { FixQualifiedTypes() : WithIndexer(false) {} Type * postmutate( QualifiedType * ); }; struct HoistStruct final : public WithDeclsToAdd, public WithGuards { /// Flattens nested struct types static void hoistStruct( std::list< Declaration * > &translationUnit ); void previsit( StructDecl * aggregateDecl ); void previsit( UnionDecl * aggregateDecl ); void previsit( StaticAssertDecl * assertDecl ); void previsit( StructInstType * type ); void previsit( UnionInstType * type ); void previsit( EnumInstType * type ); private: template< typename AggDecl > void handleAggregate( AggDecl * aggregateDecl ); AggregateDecl * parentAggr = nullptr; }; /// Fix return types so that every function returns exactly one value struct ReturnTypeFixer { static void fix( std::list< Declaration * > &translationUnit ); void postvisit( FunctionDecl * functionDecl ); void postvisit( FunctionType * ftype ); }; /// Does early resolution on the expressions that give enumeration constants their values struct ResolveEnumInitializers final : public WithIndexer, public WithGuards, public WithVisitorRef, public WithShortCircuiting { ResolveEnumInitializers( const Indexer * indexer ); void postvisit( EnumDecl * enumDecl ); private: const Indexer * local_indexer; }; /// Replaces array and function types in forall lists by appropriate pointer type and assigns each Object and Function declaration a unique ID. struct ForallPointerDecay_old final { void previsit( ObjectDecl * object ); void previsit( FunctionDecl * func ); void previsit( FunctionType * ftype ); void previsit( StructDecl * aggrDecl ); void previsit( UnionDecl * aggrDecl ); }; struct ReturnChecker : public WithGuards { /// Checks that return statements return nothing if their return type is void /// and return something if the return type is non-void. static void checkFunctionReturns( std::list< Declaration * > & translationUnit ); void previsit( FunctionDecl * functionDecl ); void previsit( ReturnStmt * returnStmt ); typedef std::list< DeclarationWithType * > ReturnVals; ReturnVals returnVals; }; struct ReplaceTypedef final : public WithVisitorRef, public WithGuards, public WithShortCircuiting, public WithDeclsToAdd { ReplaceTypedef() : scopeLevel( 0 ) {} /// Replaces typedefs by forward declarations static void replaceTypedef( std::list< Declaration * > &translationUnit ); void premutate( QualifiedType * ); Type * postmutate( QualifiedType * qualType ); Type * postmutate( TypeInstType * aggregateUseType ); Declaration * postmutate( TypedefDecl * typeDecl ); void premutate( TypeDecl * typeDecl ); void premutate( FunctionDecl * funcDecl ); void premutate( ObjectDecl * objDecl ); DeclarationWithType * postmutate( ObjectDecl * objDecl ); void premutate( CastExpr * castExpr ); void premutate( CompoundStmt * compoundStmt ); void premutate( StructDecl * structDecl ); void premutate( UnionDecl * unionDecl ); void premutate( EnumDecl * enumDecl ); void premutate( TraitDecl * ); void premutate( FunctionType * ftype ); private: template void addImplicitTypedef( AggDecl * aggDecl ); template< typename AggDecl > void handleAggregate( AggDecl * aggr ); typedef std::unique_ptr TypedefDeclPtr; typedef ScopedMap< std::string, std::pair< TypedefDeclPtr, int > > TypedefMap; typedef ScopedMap< std::string, TypeDecl * > TypeDeclMap; TypedefMap typedefNames; TypeDeclMap typedeclNames; int scopeLevel; bool inFunctionType = false; }; struct EliminateTypedef { /// removes TypedefDecls from the AST static void eliminateTypedef( std::list< Declaration * > &translationUnit ); template void handleAggregate( AggDecl * aggregateDecl ); void previsit( StructDecl * aggregateDecl ); void previsit( UnionDecl * aggregateDecl ); void previsit( CompoundStmt * compoundStmt ); }; struct VerifyCtorDtorAssign { /// ensure that constructors, destructors, and assignment have at least one /// parameter, the first of which must be a pointer, and that ctor/dtors have no /// return values. static void verify( std::list< Declaration * > &translationUnit ); void previsit( FunctionDecl * funcDecl ); }; /// ensure that generic types have the correct number of type arguments struct ValidateGenericParameters { void previsit( StructInstType * inst ); void previsit( UnionInstType * inst ); }; /// desugar declarations and uses of dimension paramaters like [N], /// from type-system managed values, to tunnneling via ordinary types, /// as char[-] in and sizeof(-) out struct TranslateDimensionGenericParameters : public WithIndexer, public WithGuards { static void translateDimensions( std::list< Declaration * > &translationUnit ); TranslateDimensionGenericParameters(); bool nextVisitedNodeIsChildOfSUIT = false; // SUIT = Struct or Union -Inst Type bool visitingChildOfSUIT = false; void changeState_ChildOfSUIT( bool newVal ); void premutate( StructInstType * sit ); void premutate( UnionInstType * uit ); void premutate( BaseSyntaxNode * node ); TypeDecl * postmutate( TypeDecl * td ); Expression * postmutate( DimensionExpr * de ); Expression * postmutate( Expression * e ); }; struct FixObjectType : public WithIndexer { /// resolves typeof type in object, function, and type declarations static void fix( std::list< Declaration * > & translationUnit ); void previsit( ObjectDecl * ); void previsit( FunctionDecl * ); void previsit( TypeDecl * ); }; struct InitializerLength { /// for array types without an explicit length, compute the length and store it so that it /// is known to the rest of the phases. For example, /// int x[] = { 1, 2, 3 }; /// int y[][2] = { { 1, 2, 3 }, { 1, 2, 3 } }; /// here x and y are known at compile-time to have length 3, so change this into /// int x[3] = { 1, 2, 3 }; /// int y[3][2] = { { 1, 2, 3 }, { 1, 2, 3 } }; static void computeLength( std::list< Declaration * > & translationUnit ); void previsit( ObjectDecl * objDecl ); }; struct ArrayLength : public WithIndexer { static void computeLength( std::list< Declaration * > & translationUnit ); void previsit( ArrayType * arrayType ); }; struct CompoundLiteral final : public WithDeclsToAdd, public WithVisitorRef { Type::StorageClasses storageClasses; void premutate( ObjectDecl * objectDecl ); Expression * postmutate( CompoundLiteralExpr * compLitExpr ); }; struct LabelAddressFixer final : public WithGuards { std::set< Label > labels; void premutate( FunctionDecl * funcDecl ); Expression * postmutate( AddressExpr * addrExpr ); }; void validate( std::list< Declaration * > &translationUnit, __attribute__((unused)) bool doDebug ) { PassVisitor hoistDecls; { Stats::Heap::newPass("validate-A"); Stats::Time::BlockGuard guard("validate-A"); VerifyCtorDtorAssign::verify( translationUnit ); // must happen before autogen, because autogen examines existing ctor/dtors acceptAll( translationUnit, hoistDecls ); ReplaceTypedef::replaceTypedef( translationUnit ); ReturnTypeFixer::fix( translationUnit ); // must happen before autogen decayEnumsAndPointers( translationUnit ); // must happen before VerifyCtorDtorAssign, because void return objects should not exist; before LinkReferenceToTypes_old because it is an indexer and needs correct types for mangling } PassVisitor fixQual; { Stats::Heap::newPass("validate-B"); Stats::Time::BlockGuard guard("validate-B"); linkReferenceToTypes( translationUnit ); // Must happen before auto-gen, because it uses the sized flag. mutateAll( translationUnit, fixQual ); // must happen after LinkReferenceToTypes_old, because aggregate members are accessed HoistStruct::hoistStruct( translationUnit ); EliminateTypedef::eliminateTypedef( translationUnit ); } PassVisitor genericParams; PassVisitor rei( nullptr ); { Stats::Heap::newPass("validate-C"); Stats::Time::BlockGuard guard("validate-C"); Stats::Time::TimeBlock("Validate Generic Parameters", [&]() { acceptAll( translationUnit, genericParams ); // check as early as possible - can't happen before LinkReferenceToTypes_old; observed failing when attempted before eliminateTypedef }); Stats::Time::TimeBlock("Translate Dimensions", [&]() { TranslateDimensionGenericParameters::translateDimensions( translationUnit ); }); if (!useNewAST) { Stats::Time::TimeBlock("Resolve Enum Initializers", [&]() { acceptAll( translationUnit, rei ); // must happen after translateDimensions because rei needs identifier lookup, which needs name mangling }); } Stats::Time::TimeBlock("Check Function Returns", [&]() { ReturnChecker::checkFunctionReturns( translationUnit ); }); Stats::Time::TimeBlock("Fix Return Statements", [&]() { InitTweak::fixReturnStatements( translationUnit ); // must happen before autogen }); } { Stats::Heap::newPass("validate-D"); Stats::Time::BlockGuard guard("validate-D"); Stats::Time::TimeBlock("Apply Concurrent Keywords", [&]() { Concurrency::applyKeywords( translationUnit ); }); Stats::Time::TimeBlock("Forall Pointer Decay", [&]() { decayForallPointers( translationUnit ); // must happen before autogenerateRoutines, after Concurrency::applyKeywords because uniqueIds must be set on declaration before resolution }); Stats::Time::TimeBlock("Hoist Control Declarations", [&]() { ControlStruct::hoistControlDecls( translationUnit ); // hoist initialization out of for statements; must happen before autogenerateRoutines }); Stats::Time::TimeBlock("Generate Autogen routines", [&]() { autogenerateRoutines( translationUnit ); // moved up, used to be below compoundLiteral - currently needs EnumAndPointerDecay_old }); } PassVisitor compoundliteral; { Stats::Heap::newPass("validate-E"); Stats::Time::BlockGuard guard("validate-E"); Stats::Time::TimeBlock("Implement Mutex Func", [&]() { Concurrency::implementMutexFuncs( translationUnit ); }); Stats::Time::TimeBlock("Implement Thread Start", [&]() { Concurrency::implementThreadStarter( translationUnit ); }); Stats::Time::TimeBlock("Compound Literal", [&]() { mutateAll( translationUnit, compoundliteral ); }); if (!useNewAST) { Stats::Time::TimeBlock("Resolve With Expressions", [&]() { ResolvExpr::resolveWithExprs( translationUnit ); // must happen before FixObjectType because user-code is resolved and may contain with variables }); } } PassVisitor labelAddrFixer; { Stats::Heap::newPass("validate-F"); Stats::Time::BlockGuard guard("validate-F"); if (!useNewAST) { Stats::Time::TimeCall("Fix Object Type", FixObjectType::fix, translationUnit); } Stats::Time::TimeCall("Initializer Length", InitializerLength::computeLength, translationUnit); if (!useNewAST) { Stats::Time::TimeCall("Array Length", ArrayLength::computeLength, translationUnit); } Stats::Time::TimeCall("Find Special Declarations", Validate::findSpecialDecls, translationUnit); Stats::Time::TimeCall("Fix Label Address", mutateAll, translationUnit, labelAddrFixer); if (!useNewAST) { Stats::Time::TimeCall("Handle Attributes", Validate::handleAttributes, translationUnit); } } } void HoistTypeDecls::handleType( Type * type ) { // some type declarations are buried in expressions and not easy to hoist during parsing; hoist them here AggregateDecl * aggr = nullptr; if ( StructInstType * inst = dynamic_cast< StructInstType * >( type ) ) { aggr = inst->baseStruct; } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * >( type ) ) { aggr = inst->baseUnion; } else if ( EnumInstType * inst = dynamic_cast< EnumInstType * >( type ) ) { aggr = inst->baseEnum; } if ( aggr && aggr->body ) { declsToAddBefore.push_front( aggr ); } } void HoistTypeDecls::previsit( SizeofExpr * expr ) { handleType( expr->type ); } void HoistTypeDecls::previsit( AlignofExpr * expr ) { handleType( expr->type ); } void HoistTypeDecls::previsit( UntypedOffsetofExpr * expr ) { handleType( expr->type ); } void HoistTypeDecls::previsit( CompoundLiteralExpr * expr ) { handleType( expr->result ); } Type * FixQualifiedTypes::postmutate( QualifiedType * qualType ) { Type * parent = qualType->parent; Type * child = qualType->child; if ( dynamic_cast< GlobalScopeType * >( qualType->parent ) ) { // .T => lookup T at global scope if ( TypeInstType * inst = dynamic_cast< TypeInstType * >( child ) ) { auto td = indexer.globalLookupType( inst->name ); if ( ! td ) { SemanticError( qualType->location, toString("Use of undefined global type ", inst->name) ); } auto base = td->base; assert( base ); Type * ret = base->clone(); ret->get_qualifiers() = qualType->get_qualifiers(); return ret; } else { // .T => T is not a type name assertf( false, "unhandled global qualified child type: %s", toCString(child) ); } } else { // S.T => S must be an aggregate type, find the declaration for T in S. AggregateDecl * aggr = nullptr; if ( StructInstType * inst = dynamic_cast< StructInstType * >( parent ) ) { aggr = inst->baseStruct; } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * > ( parent ) ) { aggr = inst->baseUnion; } else { SemanticError( qualType->location, toString("Qualified type requires an aggregate on the left, but has: ", parent) ); } assert( aggr ); // TODO: need to handle forward declarations for ( Declaration * member : aggr->members ) { if ( TypeInstType * inst = dynamic_cast< TypeInstType * >( child ) ) { // name on the right is a typedef if ( NamedTypeDecl * aggr = dynamic_cast< NamedTypeDecl * > ( member ) ) { if ( aggr->name == inst->name ) { assert( aggr->base ); Type * ret = aggr->base->clone(); ret->get_qualifiers() = qualType->get_qualifiers(); TypeSubstitution sub = parent->genericSubstitution(); sub.apply(ret); return ret; } } } else { // S.T - S is not an aggregate => error assertf( false, "unhandled qualified child type: %s", toCString(qualType) ); } } // failed to find a satisfying definition of type SemanticError( qualType->location, toString("Undefined type in qualified type: ", qualType) ); } // ... may want to link canonical SUE definition to each forward decl so that it becomes easier to lookup? } void HoistStruct::hoistStruct( std::list< Declaration * > &translationUnit ) { PassVisitor hoister; acceptAll( translationUnit, hoister ); } bool shouldHoist( Declaration * decl ) { return dynamic_cast< StructDecl * >( decl ) || dynamic_cast< UnionDecl * >( decl ) || dynamic_cast< StaticAssertDecl * >( decl ); } namespace { void qualifiedName( AggregateDecl * aggr, std::ostringstream & ss ) { if ( aggr->parent ) qualifiedName( aggr->parent, ss ); ss << "__" << aggr->name; } // mangle nested type names using entire parent chain std::string qualifiedName( AggregateDecl * aggr ) { std::ostringstream ss; qualifiedName( aggr, ss ); return ss.str(); } } template< typename AggDecl > void HoistStruct::handleAggregate( AggDecl * aggregateDecl ) { if ( parentAggr ) { aggregateDecl->parent = parentAggr; aggregateDecl->name = qualifiedName( aggregateDecl ); // Add elements in stack order corresponding to nesting structure. declsToAddBefore.push_front( aggregateDecl ); } else { GuardValue( parentAggr ); parentAggr = aggregateDecl; } // if // Always remove the hoisted aggregate from the inner structure. GuardAction( [aggregateDecl]() { filter( aggregateDecl->members, shouldHoist, false ); } ); } void HoistStruct::previsit( StaticAssertDecl * assertDecl ) { if ( parentAggr ) { declsToAddBefore.push_back( assertDecl ); } } void HoistStruct::previsit( StructDecl * aggregateDecl ) { handleAggregate( aggregateDecl ); } void HoistStruct::previsit( UnionDecl * aggregateDecl ) { handleAggregate( aggregateDecl ); } void HoistStruct::previsit( StructInstType * type ) { // need to reset type name after expanding to qualified name assert( type->baseStruct ); type->name = type->baseStruct->name; } void HoistStruct::previsit( UnionInstType * type ) { assert( type->baseUnion ); type->name = type->baseUnion->name; } void HoistStruct::previsit( EnumInstType * type ) { assert( type->baseEnum ); type->name = type->baseEnum->name; } bool isTypedef( Declaration * decl ) { return dynamic_cast< TypedefDecl * >( decl ); } void EliminateTypedef::eliminateTypedef( std::list< Declaration * > &translationUnit ) { PassVisitor eliminator; acceptAll( translationUnit, eliminator ); filter( translationUnit, isTypedef, true ); } template< typename AggDecl > void EliminateTypedef::handleAggregate( AggDecl * aggregateDecl ) { filter( aggregateDecl->members, isTypedef, true ); } void EliminateTypedef::previsit( StructDecl * aggregateDecl ) { handleAggregate( aggregateDecl ); } void EliminateTypedef::previsit( UnionDecl * aggregateDecl ) { handleAggregate( aggregateDecl ); } void EliminateTypedef::previsit( CompoundStmt * compoundStmt ) { // remove and delete decl stmts filter( compoundStmt->kids, [](Statement * stmt) { if ( DeclStmt * declStmt = dynamic_cast< DeclStmt * >( stmt ) ) { if ( dynamic_cast< TypedefDecl * >( declStmt->decl ) ) { return true; } // if } // if return false; }, true); } // expand assertions from trait instance, performing the appropriate type variable substitutions template< typename Iterator > void expandAssertions( TraitInstType * inst, Iterator out ) { assertf( inst->baseTrait, "Trait instance not linked to base trait: %s", toCString( inst ) ); std::list< DeclarationWithType * > asserts; for ( Declaration * decl : inst->baseTrait->members ) { asserts.push_back( strict_dynamic_cast( decl->clone() ) ); } // substitute trait decl parameters for instance parameters applySubstitution( inst->baseTrait->parameters.begin(), inst->baseTrait->parameters.end(), inst->parameters.begin(), asserts.begin(), asserts.end(), out ); } ResolveEnumInitializers::ResolveEnumInitializers( const Indexer * other_indexer ) : WithIndexer( true ) { if ( other_indexer ) { local_indexer = other_indexer; } else { local_indexer = &indexer; } // if } void ResolveEnumInitializers::postvisit( EnumDecl * enumDecl ) { if ( enumDecl->body ) { for ( Declaration * member : enumDecl->members ) { ObjectDecl * field = strict_dynamic_cast( member ); if ( field->init ) { // need to resolve enumerator initializers early so that other passes that determine if an expression is constexpr have the appropriate information. SingleInit * init = strict_dynamic_cast( field->init ); if ( !enumDecl->base || dynamic_cast(enumDecl->base)) ResolvExpr::findSingleExpression( init->value, new BasicType( Type::Qualifiers(), BasicType::SignedInt ), indexer ); else { if (dynamic_cast(enumDecl->base)) { auto typePtr = dynamic_cast(enumDecl->base); ResolvExpr::findSingleExpression( init->value, new PointerType( Type::Qualifiers(), typePtr->base ), indexer ); } else { ResolvExpr::findSingleExpression( init->value, new BasicType( Type::Qualifiers(), BasicType::SignedInt ), indexer ); } } } } } // if } /// Fix up assertions - flattens assertion lists, removing all trait instances void forallFixer( std::list< TypeDecl * > & forall, BaseSyntaxNode * node ) { for ( TypeDecl * type : forall ) { std::list< DeclarationWithType * > asserts; asserts.splice( asserts.end(), type->assertions ); // expand trait instances into their members for ( DeclarationWithType * assertion : asserts ) { if ( TraitInstType * traitInst = dynamic_cast< TraitInstType * >( assertion->get_type() ) ) { // expand trait instance into all of its members expandAssertions( traitInst, back_inserter( type->assertions ) ); delete traitInst; } else { // pass other assertions through type->assertions.push_back( assertion ); } // if } // for // apply FixFunction to every assertion to check for invalid void type for ( DeclarationWithType *& assertion : type->assertions ) { bool isVoid = fixFunction( assertion ); if ( isVoid ) { SemanticError( node, "invalid type void in assertion of function " ); } // if } // for // normalizeAssertions( type->assertions ); } // for } /// Replace all traits in assertion lists with their assertions. void expandTraits( std::list< TypeDecl * > & forall ) { for ( TypeDecl * type : forall ) { std::list< DeclarationWithType * > asserts; asserts.splice( asserts.end(), type->assertions ); // expand trait instances into their members for ( DeclarationWithType * assertion : asserts ) { if ( TraitInstType * traitInst = dynamic_cast< TraitInstType * >( assertion->get_type() ) ) { // expand trait instance into all of its members expandAssertions( traitInst, back_inserter( type->assertions ) ); delete traitInst; } else { // pass other assertions through type->assertions.push_back( assertion ); } // if } // for } } /// Fix each function in the assertion list and check for invalid void type. void fixAssertions( std::list< TypeDecl * > & forall, BaseSyntaxNode * node ) { for ( TypeDecl * type : forall ) { for ( DeclarationWithType *& assertion : type->assertions ) { bool isVoid = fixFunction( assertion ); if ( isVoid ) { SemanticError( node, "invalid type void in assertion of function " ); } // if } // for } } void ForallPointerDecay_old::previsit( ObjectDecl * object ) { // ensure that operator names only apply to functions or function pointers if ( CodeGen::isOperator( object->name ) && ! dynamic_cast< FunctionType * >( object->type->stripDeclarator() ) ) { SemanticError( object->location, toCString( "operator ", object->name.c_str(), " is not a function or function pointer." ) ); } object->fixUniqueId(); } void ForallPointerDecay_old::previsit( FunctionDecl * func ) { func->fixUniqueId(); } void ForallPointerDecay_old::previsit( FunctionType * ftype ) { forallFixer( ftype->forall, ftype ); } void ForallPointerDecay_old::previsit( StructDecl * aggrDecl ) { forallFixer( aggrDecl->parameters, aggrDecl ); } void ForallPointerDecay_old::previsit( UnionDecl * aggrDecl ) { forallFixer( aggrDecl->parameters, aggrDecl ); } void ReturnChecker::checkFunctionReturns( std::list< Declaration * > & translationUnit ) { PassVisitor checker; acceptAll( translationUnit, checker ); } void ReturnChecker::previsit( FunctionDecl * functionDecl ) { GuardValue( returnVals ); returnVals = functionDecl->get_functionType()->get_returnVals(); } void ReturnChecker::previsit( ReturnStmt * returnStmt ) { // Previously this also checked for the existence of an expr paired with no return values on // the function return type. This is incorrect, since you can have an expression attached to // a return statement in a void-returning function in C. The expression is treated as if it // were cast to void. if ( ! returnStmt->get_expr() && returnVals.size() != 0 ) { SemanticError( returnStmt, "Non-void function returns no values: " ); } } void ReplaceTypedef::replaceTypedef( std::list< Declaration * > &translationUnit ) { PassVisitor eliminator; mutateAll( translationUnit, eliminator ); if ( eliminator.pass.typedefNames.count( "size_t" ) ) { // grab and remember declaration of size_t Validate::SizeType = eliminator.pass.typedefNames["size_t"].first->base->clone(); } else { // xxx - missing global typedef for size_t - default to long unsigned int, even though that may be wrong // eventually should have a warning for this case. Validate::SizeType = new BasicType( Type::Qualifiers(), BasicType::LongUnsignedInt ); } } void ReplaceTypedef::premutate( QualifiedType * ) { visit_children = false; } Type * ReplaceTypedef::postmutate( QualifiedType * qualType ) { // replacing typedefs only makes sense for the 'oldest ancestor' of the qualified type qualType->parent = qualType->parent->acceptMutator( * visitor ); return qualType; } static bool isNonParameterAttribute( Attribute * attr ) { static const std::vector bad_names = { "aligned", "__aligned__", }; for ( auto name : bad_names ) { if ( name == attr->name ) { return true; } } return false; } Type * ReplaceTypedef::postmutate( TypeInstType * typeInst ) { // instances of typedef types will come here. If it is an instance // of a typdef type, link the instance to its actual type. TypedefMap::const_iterator def = typedefNames.find( typeInst->name ); if ( def != typedefNames.end() ) { Type * ret = def->second.first->base->clone(); ret->location = typeInst->location; ret->get_qualifiers() |= typeInst->get_qualifiers(); // GCC ignores certain attributes if they arrive by typedef, this mimics that. if ( inFunctionType ) { ret->attributes.remove_if( isNonParameterAttribute ); } ret->attributes.splice( ret->attributes.end(), typeInst->attributes ); // place instance parameters on the typedef'd type if ( ! typeInst->parameters.empty() ) { ReferenceToType * rtt = dynamic_cast(ret); if ( ! rtt ) { SemanticError( typeInst->location, "Cannot apply type parameters to base type of " + typeInst->name ); } rtt->parameters.clear(); cloneAll( typeInst->parameters, rtt->parameters ); mutateAll( rtt->parameters, * visitor ); // recursively fix typedefs on parameters } // if delete typeInst; return ret; } else { TypeDeclMap::const_iterator base = typedeclNames.find( typeInst->name ); if ( base == typedeclNames.end() ) { SemanticError( typeInst->location, toString("Use of undefined type ", typeInst->name) ); } typeInst->set_baseType( base->second ); return typeInst; } // if assert( false ); } struct VarLenChecker : WithShortCircuiting { void previsit( FunctionType * ) { visit_children = false; } void previsit( ArrayType * at ) { isVarLen |= at->isVarLen; } bool isVarLen = false; }; bool isVariableLength( Type * t ) { PassVisitor varLenChecker; maybeAccept( t, varLenChecker ); return varLenChecker.pass.isVarLen; } Declaration * ReplaceTypedef::postmutate( TypedefDecl * tyDecl ) { if ( typedefNames.count( tyDecl->name ) == 1 && typedefNames[ tyDecl->name ].second == scopeLevel ) { // typedef to the same name from the same scope // must be from the same type Type * t1 = tyDecl->base; Type * t2 = typedefNames[ tyDecl->name ].first->base; if ( ! ResolvExpr::typesCompatible( t1, t2, Indexer() ) ) { SemanticError( tyDecl->location, "Cannot redefine typedef: " + tyDecl->name ); } // Cannot redefine VLA typedefs. Note: this is slightly incorrect, because our notion of VLAs // at this point in the translator is imprecise. In particular, this will disallow redefining typedefs // with arrays whose dimension is an enumerator or a cast of a constant/enumerator. The effort required // to fix this corner case likely outweighs the utility of allowing it. if ( isVariableLength( t1 ) || isVariableLength( t2 ) ) { SemanticError( tyDecl->location, "Cannot redefine typedef: " + tyDecl->name ); } } else { typedefNames[ tyDecl->name ] = std::make_pair( TypedefDeclPtr( tyDecl ), scopeLevel ); } // if // When a typedef is a forward declaration: // typedef struct screen SCREEN; // the declaration portion must be retained: // struct screen; // because the expansion of the typedef is: // void rtn( SCREEN * p ) => void rtn( struct screen * p ) // hence the type-name "screen" must be defined. // Note, qualifiers on the typedef are superfluous for the forward declaration. Type * designatorType = tyDecl->base->stripDeclarator(); if ( StructInstType * aggDecl = dynamic_cast< StructInstType * >( designatorType ) ) { declsToAddBefore.push_back( new StructDecl( aggDecl->name, AggregateDecl::Struct, noAttributes, tyDecl->linkage ) ); } else if ( UnionInstType * aggDecl = dynamic_cast< UnionInstType * >( designatorType ) ) { declsToAddBefore.push_back( new UnionDecl( aggDecl->name, noAttributes, tyDecl->linkage ) ); } else if ( EnumInstType * enumInst = dynamic_cast< EnumInstType * >( designatorType ) ) { if ( enumInst->baseEnum ) { const EnumDecl * enumDecl = enumInst->baseEnum; declsToAddBefore.push_back( new EnumDecl( enumDecl->name, noAttributes, enumDecl->isTyped, tyDecl->linkage, enumDecl->base ) ); } else { declsToAddBefore.push_back( new EnumDecl( enumInst->name, noAttributes, tyDecl->linkage ) ); } } // if return tyDecl->clone(); } void ReplaceTypedef::premutate( TypeDecl * typeDecl ) { TypedefMap::iterator i = typedefNames.find( typeDecl->name ); if ( i != typedefNames.end() ) { typedefNames.erase( i ) ; } // if typedeclNames.insert( typeDecl->name, typeDecl ); } void ReplaceTypedef::premutate( FunctionDecl * ) { GuardScope( typedefNames ); GuardScope( typedeclNames ); } void ReplaceTypedef::premutate( ObjectDecl * ) { GuardScope( typedefNames ); GuardScope( typedeclNames ); } DeclarationWithType * ReplaceTypedef::postmutate( ObjectDecl * objDecl ) { if ( FunctionType * funtype = dynamic_cast( objDecl->type ) ) { // function type? // replace the current object declaration with a function declaration FunctionDecl * newDecl = new FunctionDecl( objDecl->name, objDecl->get_storageClasses(), objDecl->linkage, funtype, 0, objDecl->attributes, objDecl->get_funcSpec() ); objDecl->attributes.clear(); objDecl->set_type( nullptr ); delete objDecl; return newDecl; } // if return objDecl; } void ReplaceTypedef::premutate( CastExpr * ) { GuardScope( typedefNames ); GuardScope( typedeclNames ); } void ReplaceTypedef::premutate( CompoundStmt * ) { GuardScope( typedefNames ); GuardScope( typedeclNames ); scopeLevel += 1; GuardAction( [this](){ scopeLevel -= 1; } ); } template void ReplaceTypedef::addImplicitTypedef( AggDecl * aggDecl ) { if ( typedefNames.count( aggDecl->get_name() ) == 0 ) { Type * type = nullptr; if ( StructDecl * newDeclStructDecl = dynamic_cast< StructDecl * >( aggDecl ) ) { type = new StructInstType( Type::Qualifiers(), newDeclStructDecl->get_name() ); } else if ( UnionDecl * newDeclUnionDecl = dynamic_cast< UnionDecl * >( aggDecl ) ) { type = new UnionInstType( Type::Qualifiers(), newDeclUnionDecl->get_name() ); } else if ( EnumDecl * newDeclEnumDecl = dynamic_cast< EnumDecl * >( aggDecl ) ) { type = new EnumInstType( Type::Qualifiers(), newDeclEnumDecl->get_name() ); } // if TypedefDeclPtr tyDecl( new TypedefDecl( aggDecl->get_name(), aggDecl->location, Type::StorageClasses(), type, aggDecl->get_linkage() ) ); typedefNames[ aggDecl->get_name() ] = std::make_pair( std::move( tyDecl ), scopeLevel ); // add the implicit typedef to the AST declsToAddBefore.push_back( new TypedefDecl( aggDecl->get_name(), aggDecl->location, Type::StorageClasses(), type->clone(), aggDecl->get_linkage() ) ); } // if } template< typename AggDecl > void ReplaceTypedef::handleAggregate( AggDecl * aggr ) { SemanticErrorException errors; ValueGuard< std::list > oldBeforeDecls( declsToAddBefore ); ValueGuard< std::list > oldAfterDecls ( declsToAddAfter ); declsToAddBefore.clear(); declsToAddAfter.clear(); GuardScope( typedefNames ); GuardScope( typedeclNames ); mutateAll( aggr->parameters, * visitor ); mutateAll( aggr->attributes, * visitor ); // unroll mutateAll for aggr->members so that implicit typedefs for nested types are added to the aggregate body. for ( std::list< Declaration * >::iterator i = aggr->members.begin(); i != aggr->members.end(); ++i ) { if ( !declsToAddAfter.empty() ) { aggr->members.splice( i, declsToAddAfter ); } try { * i = maybeMutate( * i, * visitor ); } catch ( SemanticErrorException &e ) { errors.append( e ); } if ( !declsToAddBefore.empty() ) { aggr->members.splice( i, declsToAddBefore ); } } if ( !declsToAddAfter.empty() ) { aggr->members.splice( aggr->members.end(), declsToAddAfter ); } if ( !errors.isEmpty() ) { throw errors; } } void ReplaceTypedef::premutate( StructDecl * structDecl ) { visit_children = false; addImplicitTypedef( structDecl ); handleAggregate( structDecl ); } void ReplaceTypedef::premutate( UnionDecl * unionDecl ) { visit_children = false; addImplicitTypedef( unionDecl ); handleAggregate( unionDecl ); } void ReplaceTypedef::premutate( EnumDecl * enumDecl ) { addImplicitTypedef( enumDecl ); } void ReplaceTypedef::premutate( FunctionType * ) { GuardValue( inFunctionType ); inFunctionType = true; } void ReplaceTypedef::premutate( TraitDecl * ) { GuardScope( typedefNames ); GuardScope( typedeclNames); } void VerifyCtorDtorAssign::verify( std::list< Declaration * > & translationUnit ) { PassVisitor verifier; acceptAll( translationUnit, verifier ); } void VerifyCtorDtorAssign::previsit( FunctionDecl * funcDecl ) { FunctionType * funcType = funcDecl->get_functionType(); std::list< DeclarationWithType * > &returnVals = funcType->get_returnVals(); std::list< DeclarationWithType * > ¶ms = funcType->get_parameters(); if ( CodeGen::isCtorDtorAssign( funcDecl->get_name() ) ) { // TODO: also check /=, etc. if ( params.size() == 0 ) { SemanticError( funcDecl->location, "Constructors, destructors, and assignment functions require at least one parameter." ); } ReferenceType * refType = dynamic_cast< ReferenceType * >( params.front()->get_type() ); if ( ! refType ) { SemanticError( funcDecl->location, "First parameter of a constructor, destructor, or assignment function must be a reference." ); } if ( CodeGen::isCtorDtor( funcDecl->get_name() ) && returnVals.size() != 0 ) { if(!returnVals.front()->get_type()->isVoid()) { SemanticError( funcDecl->location, "Constructors and destructors cannot have explicit return values." ); } } } } // Test for special name on a generic parameter. Special treatment for the // special name is a bootstrapping hack. In most cases, the worlds of T's // and of N's don't overlap (normal treamtemt). The foundations in // array.hfa use tagging for both types and dimensions. Tagging treats // its subject parameter even more opaquely than T&, which assumes it is // possible to have a pointer/reference to such an object. Tagging only // seeks to identify the type-system resident at compile time. Both N's // and T's can make tags. The tag definition uses the special name, which // is treated as "an N or a T." This feature is not inteded to be used // outside of the definition and immediate uses of a tag. static inline bool isReservedTysysIdOnlyName( const std::string & name ) { // name's prefix was __CFA_tysys_id_only, before it got wrapped in __..._generic int foundAt = name.find("__CFA_tysys_id_only"); if (foundAt == 0) return true; if (foundAt == 2 && name[0] == '_' && name[1] == '_') return true; return false; } template< typename Aggr > void validateGeneric( Aggr * inst ) { std::list< TypeDecl * > * params = inst->get_baseParameters(); if ( params ) { std::list< Expression * > & args = inst->get_parameters(); // insert defaults arguments when a type argument is missing (currently only supports missing arguments at the end of the list). // A substitution is used to ensure that defaults are replaced correctly, e.g., // forall(otype T, otype alloc = heap_allocator(T)) struct vector; // vector(int) v; // after insertion of default values becomes // vector(int, heap_allocator(T)) // and the substitution is built with T=int so that after substitution, the result is // vector(int, heap_allocator(int)) TypeSubstitution sub; auto paramIter = params->begin(); auto argIter = args.begin(); for ( ; paramIter != params->end(); ++paramIter, ++argIter ) { if ( argIter != args.end() ) { TypeExpr * expr = dynamic_cast< TypeExpr * >( * argIter ); if ( expr ) { sub.add( (* paramIter)->get_name(), expr->get_type()->clone() ); } } else { Type * defaultType = (* paramIter)->get_init(); if ( defaultType ) { args.push_back( new TypeExpr( defaultType->clone() ) ); sub.add( (* paramIter)->get_name(), defaultType->clone() ); argIter = std::prev(args.end()); } else { SemanticError( inst, "Too few type arguments in generic type " ); } } assert( argIter != args.end() ); bool typeParamDeclared = (*paramIter)->kind != TypeDecl::Kind::Dimension; bool typeArgGiven; if ( isReservedTysysIdOnlyName( (*paramIter)->name ) ) { // coerce a match when declaration is reserved name, which means "either" typeArgGiven = typeParamDeclared; } else { typeArgGiven = dynamic_cast< TypeExpr * >( * argIter ); } if ( ! typeParamDeclared && typeArgGiven ) SemanticError( inst, "Type argument given for value parameter: " ); if ( typeParamDeclared && ! typeArgGiven ) SemanticError( inst, "Expression argument given for type parameter: " ); } sub.apply( inst ); if ( args.size() > params->size() ) SemanticError( inst, "Too many type arguments in generic type " ); } } void ValidateGenericParameters::previsit( StructInstType * inst ) { validateGeneric( inst ); } void ValidateGenericParameters::previsit( UnionInstType * inst ) { validateGeneric( inst ); } void TranslateDimensionGenericParameters::translateDimensions( std::list< Declaration * > &translationUnit ) { PassVisitor translator; mutateAll( translationUnit, translator ); } TranslateDimensionGenericParameters::TranslateDimensionGenericParameters() : WithIndexer( false ) {} // Declaration of type variable: forall( [N] ) -> forall( N & | sized( N ) ) TypeDecl * TranslateDimensionGenericParameters::postmutate( TypeDecl * td ) { if ( td->kind == TypeDecl::Dimension ) { td->kind = TypeDecl::Dtype; if ( ! isReservedTysysIdOnlyName( td->name ) ) { td->sized = true; } } return td; } // Situational awareness: // array( float, [[currentExpr]] ) has visitingChildOfSUIT == true // array( float, [[currentExpr]] - 1 ) has visitingChildOfSUIT == false // size_t x = [[currentExpr]] has visitingChildOfSUIT == false void TranslateDimensionGenericParameters::changeState_ChildOfSUIT( bool newVal ) { GuardValue( nextVisitedNodeIsChildOfSUIT ); GuardValue( visitingChildOfSUIT ); visitingChildOfSUIT = nextVisitedNodeIsChildOfSUIT; nextVisitedNodeIsChildOfSUIT = newVal; } void TranslateDimensionGenericParameters::premutate( StructInstType * sit ) { (void) sit; changeState_ChildOfSUIT(true); } void TranslateDimensionGenericParameters::premutate( UnionInstType * uit ) { (void) uit; changeState_ChildOfSUIT(true); } void TranslateDimensionGenericParameters::premutate( BaseSyntaxNode * node ) { (void) node; changeState_ChildOfSUIT(false); } // Passing values as dimension arguments: array( float, 7 ) -> array( float, char[ 7 ] ) // Consuming dimension parameters: size_t x = N - 1 ; -> size_t x = sizeof(N) - 1 ; // Intertwined reality: array( float, N ) -> array( float, N ) // array( float, N - 1 ) -> array( float, char[ sizeof(N) - 1 ] ) // Intertwined case 1 is not just an optimization. // Avoiding char[sizeof(-)] is necessary to enable the call of f to bind the value of N, in: // forall([N]) void f( array(float, N) & ); // array(float, 7) a; // f(a); Expression * TranslateDimensionGenericParameters::postmutate( DimensionExpr * de ) { // Expression de is an occurrence of N in LHS of above examples. // Look up the name that de references. // If we are in a struct body, then this reference can be to an entry of the stuct's forall list. // Whether or not we are in a struct body, this reference can be to an entry of a containing function's forall list. // If we are in a struct body, then the stuct's forall declarations are innermost (functions don't occur in structs). // Thus, a potential struct's declaration is highest priority. // A struct's forall declarations are already renamed with _generic_ suffix. Try that name variant first. std::string useName = "__" + de->name + "_generic_"; TypeDecl * namedParamDecl = const_cast( strict_dynamic_cast( indexer.lookupType( useName ) ) ); if ( ! namedParamDecl ) { useName = de->name; namedParamDecl = const_cast( strict_dynamic_cast( indexer.lookupType( useName ) ) ); } // Expect to find it always. A misspelled name would have been parsed as an identifier. assert( namedParamDecl && "Type-system-managed value name not found in symbol table" ); delete de; TypeInstType * refToDecl = new TypeInstType( 0, useName, namedParamDecl ); if ( visitingChildOfSUIT ) { // As in postmutate( Expression * ), topmost expression needs a TypeExpr wrapper // But avoid ArrayType-Sizeof return new TypeExpr( refToDecl ); } else { // the N occurrence is being used directly as a runtime value, // if we are in a type instantiation, then the N is within a bigger value computation return new SizeofExpr( refToDecl ); } } Expression * TranslateDimensionGenericParameters::postmutate( Expression * e ) { if ( visitingChildOfSUIT ) { // e is an expression used as an argument to instantiate a type if (! dynamic_cast< TypeExpr * >( e ) ) { // e is a value expression // but not a DimensionExpr, which has a distinct postmutate Type * typeExprContent = new ArrayType( 0, new BasicType( 0, BasicType::Char ), e, true, false ); TypeExpr * result = new TypeExpr( typeExprContent ); return result; } } return e; } void CompoundLiteral::premutate( ObjectDecl * objectDecl ) { storageClasses = objectDecl->get_storageClasses(); } Expression * CompoundLiteral::postmutate( CompoundLiteralExpr * compLitExpr ) { // transform [storage_class] ... (struct S){ 3, ... }; // into [storage_class] struct S temp = { 3, ... }; static UniqueName indexName( "_compLit" ); ObjectDecl * tempvar = new ObjectDecl( indexName.newName(), storageClasses, LinkageSpec::C, nullptr, compLitExpr->get_result(), compLitExpr->get_initializer() ); compLitExpr->set_result( nullptr ); compLitExpr->set_initializer( nullptr ); delete compLitExpr; declsToAddBefore.push_back( tempvar ); // add modified temporary to current block return new VariableExpr( tempvar ); } void ReturnTypeFixer::fix( std::list< Declaration * > &translationUnit ) { PassVisitor fixer; acceptAll( translationUnit, fixer ); } void ReturnTypeFixer::postvisit( FunctionDecl * functionDecl ) { FunctionType * ftype = functionDecl->get_functionType(); std::list< DeclarationWithType * > & retVals = ftype->get_returnVals(); assertf( retVals.size() == 0 || retVals.size() == 1, "Function %s has too many return values: %zu", functionDecl->get_name().c_str(), retVals.size() ); if ( retVals.size() == 1 ) { // ensure all function return values have a name - use the name of the function to disambiguate (this also provides a nice bit of help for debugging). // ensure other return values have a name. DeclarationWithType * ret = retVals.front(); if ( ret->get_name() == "" ) { ret->set_name( toString( "_retval_", CodeGen::genName( functionDecl ) ) ); } ret->get_attributes().push_back( new Attribute( "unused" ) ); } } void ReturnTypeFixer::postvisit( FunctionType * ftype ) { // xxx - need to handle named return values - this information needs to be saved somehow // so that resolution has access to the names. // Note that this pass needs to happen early so that other passes which look for tuple types // find them in all of the right places, including function return types. std::list< DeclarationWithType * > & retVals = ftype->get_returnVals(); if ( retVals.size() > 1 ) { // generate a single return parameter which is the tuple of all of the return values TupleType * tupleType = strict_dynamic_cast< TupleType * >( ResolvExpr::extractResultType( ftype ) ); // ensure return value is not destructed by explicitly creating an empty ListInit node wherein maybeConstruct is false. ObjectDecl * newRet = new ObjectDecl( "", Type::StorageClasses(), LinkageSpec::Cforall, 0, tupleType, new ListInit( std::list(), noDesignators, false ) ); deleteAll( retVals ); retVals.clear(); retVals.push_back( newRet ); } } void FixObjectType::fix( std::list< Declaration * > & translationUnit ) { PassVisitor fixer; acceptAll( translationUnit, fixer ); } void FixObjectType::previsit( ObjectDecl * objDecl ) { Type * new_type = ResolvExpr::resolveTypeof( objDecl->get_type(), indexer ); objDecl->set_type( new_type ); } void FixObjectType::previsit( FunctionDecl * funcDecl ) { Type * new_type = ResolvExpr::resolveTypeof( funcDecl->type, indexer ); funcDecl->set_type( new_type ); } void FixObjectType::previsit( TypeDecl * typeDecl ) { if ( typeDecl->get_base() ) { Type * new_type = ResolvExpr::resolveTypeof( typeDecl->get_base(), indexer ); typeDecl->set_base( new_type ); } // if } void InitializerLength::computeLength( std::list< Declaration * > & translationUnit ) { PassVisitor len; acceptAll( translationUnit, len ); } void ArrayLength::computeLength( std::list< Declaration * > & translationUnit ) { PassVisitor len; acceptAll( translationUnit, len ); } void InitializerLength::previsit( ObjectDecl * objDecl ) { if ( ArrayType * at = dynamic_cast< ArrayType * >( objDecl->type ) ) { if ( at->dimension ) return; if ( ListInit * init = dynamic_cast< ListInit * >( objDecl->init ) ) { at->dimension = new ConstantExpr( Constant::from_ulong( init->initializers.size() ) ); } } } void ArrayLength::previsit( ArrayType * type ) { if ( type->dimension ) { // need to resolve array dimensions early so that constructor code can correctly determine // if a type is a VLA (and hence whether its elements need to be constructed) ResolvExpr::findSingleExpression( type->dimension, Validate::SizeType->clone(), indexer ); // must re-evaluate whether a type is a VLA, now that more information is available // (e.g. the dimension may have been an enumerator, which was unknown prior to this step) type->isVarLen = ! InitTweak::isConstExpr( type->dimension ); } } struct LabelFinder { std::set< Label > & labels; LabelFinder( std::set< Label > & labels ) : labels( labels ) {} void previsit( Statement * stmt ) { for ( Label & l : stmt->labels ) { labels.insert( l ); } } }; void LabelAddressFixer::premutate( FunctionDecl * funcDecl ) { GuardValue( labels ); PassVisitor finder( labels ); funcDecl->accept( finder ); } Expression * LabelAddressFixer::postmutate( AddressExpr * addrExpr ) { // convert &&label into label address if ( AddressExpr * inner = dynamic_cast< AddressExpr * >( addrExpr->arg ) ) { if ( NameExpr * nameExpr = dynamic_cast< NameExpr * >( inner->arg ) ) { if ( labels.count( nameExpr->name ) ) { Label name = nameExpr->name; delete addrExpr; return new LabelAddressExpr( name ); } } } return addrExpr; } } // namespace SymTab // Local Variables: // // tab-width: 4 // // mode: c++ // // compile-command: "make install" // // End: //