[490fb92e] | 1 | #include "FixInit.h" |
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| 2 | |
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| 3 | #include <stddef.h> // for NULL |
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| 4 | #include <algorithm> // for set_difference, copy_if |
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| 5 | #include <cassert> // for assert, strict_dynamic_cast |
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| 6 | #include <iostream> // for operator<<, ostream, basic_ost... |
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| 7 | #include <iterator> // for insert_iterator, back_inserter |
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| 8 | #include <list> // for _List_iterator, list, list<>::... |
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| 9 | #include <map> // for _Rb_tree_iterator, _Rb_tree_co... |
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| 10 | #include <memory> // for allocator_traits<>::value_type |
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| 11 | #include <set> // for set, set<>::value_type |
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| 12 | #include <unordered_map> // for unordered_map, unordered_map<>... |
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| 13 | #include <unordered_set> // for unordered_set |
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| 14 | #include <utility> // for pair |
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| 15 | |
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[fb4dc28] | 16 | #include "AST/DeclReplacer.hpp" |
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| 17 | #include "AST/Expr.hpp" |
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[e01eb4a] | 18 | #include "AST/Inspect.hpp" // for getFunction, getPointerBase, g... |
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[fb4dc28] | 19 | #include "AST/Node.hpp" |
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| 20 | #include "AST/Pass.hpp" |
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| 21 | #include "AST/Print.hpp" |
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| 22 | #include "AST/SymbolTable.hpp" |
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| 23 | #include "AST/Type.hpp" |
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[b29a1e8] | 24 | #include "CodeGen/OperatorTable.h" // for isConstructor, isCtorDtor, isD... |
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[490fb92e] | 25 | #include "Common/SemanticError.h" // for SemanticError |
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[9feb34b] | 26 | #include "Common/ToString.hpp" // for toCString |
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[490fb92e] | 27 | #include "Common/UniqueName.h" // for UniqueName |
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| 28 | #include "FixGlobalInit.h" // for fixGlobalInit |
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| 29 | #include "GenInit.h" // for genCtorDtor |
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| 30 | #include "GenPoly/GenPoly.h" // for getFunctionType |
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| 31 | #include "ResolvExpr/Resolver.h" // for findVoidExpression |
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[e563edf] | 32 | #include "ResolvExpr/Unify.h" // for typesCompatible |
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[fb4dc28] | 33 | #include "SymTab/GenImplicitCall.hpp" // for genImplicitCall |
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[490fb92e] | 34 | |
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[fa761c2] | 35 | bool ctordtorp = false; // print all debug |
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| 36 | bool ctorp = false; // print ctor debug |
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| 37 | bool cpctorp = false; // print copy ctor debug |
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| 38 | bool dtorp = false; // print dtor debug |
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[490fb92e] | 39 | #define PRINT( text ) if ( ctordtorp ) { text } |
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| 40 | #define CP_CTOR_PRINT( text ) if ( ctordtorp || cpctorp ) { text } |
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| 41 | #define DTOR_PRINT( text ) if ( ctordtorp || dtorp ) { text } |
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| 42 | |
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| 43 | namespace InitTweak { |
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[17c13b9] | 44 | |
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[0e707bd] | 45 | namespace { |
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[fb4dc28] | 46 | |
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[17c13b9] | 47 | // Shallow copy the pointer list for return. |
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| 48 | std::vector<ast::ptr<ast::TypeDecl>> getGenericParams( const ast::Type * t ) { |
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| 49 | if ( auto inst = dynamic_cast<const ast::StructInstType *>( t ) ) { |
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| 50 | return inst->base->params; |
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[a4ed165] | 51 | } else if ( auto inst = dynamic_cast<const ast::UnionInstType *>( t ) ) { |
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[17c13b9] | 52 | return inst->base->params; |
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[fb4dc28] | 53 | } |
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[17c13b9] | 54 | return {}; |
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| 55 | } |
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[fb4dc28] | 56 | |
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[17c13b9] | 57 | /// Given type T, generate type of default ctor/dtor, i.e. function type void (*) (T &). |
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| 58 | ast::FunctionDecl * genDefaultFunc( |
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| 59 | const CodeLocation loc, |
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| 60 | const std::string fname, |
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| 61 | const ast::Type * paramType, |
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| 62 | bool maybePolymorphic = true) { |
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| 63 | std::vector<ast::ptr<ast::TypeDecl>> typeParams; |
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| 64 | if ( maybePolymorphic ) typeParams = getGenericParams( paramType ); |
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| 65 | auto dstParam = new ast::ObjectDecl( loc, |
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| 66 | "_dst", |
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| 67 | new ast::ReferenceType( paramType ), |
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| 68 | nullptr, |
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| 69 | {}, |
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| 70 | ast::Linkage::Cforall |
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| 71 | ); |
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| 72 | return new ast::FunctionDecl( loc, |
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| 73 | fname, |
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| 74 | std::move(typeParams), |
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[37273c8] | 75 | {}, |
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[17c13b9] | 76 | {dstParam}, |
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| 77 | {}, |
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| 78 | new ast::CompoundStmt(loc), |
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| 79 | {}, |
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| 80 | ast::Linkage::Cforall |
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| 81 | ); |
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| 82 | } |
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[490fb92e] | 83 | |
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[17c13b9] | 84 | struct SelfAssignChecker { |
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| 85 | void previsit( const ast::ApplicationExpr * appExpr ); |
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| 86 | }; |
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| 87 | |
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| 88 | struct StmtExprResult { |
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| 89 | const ast::StmtExpr * previsit( const ast::StmtExpr * stmtExpr ); |
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| 90 | }; |
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| 91 | |
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| 92 | /// wrap function application expressions as ImplicitCopyCtorExpr nodes so that it is easy to identify which |
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| 93 | /// function calls need their parameters to be copy constructed |
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| 94 | struct InsertImplicitCalls : public ast::WithShortCircuiting { |
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| 95 | const ast::Expr * postvisit( const ast::ApplicationExpr * appExpr ); |
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| 96 | |
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| 97 | // only handles each UniqueExpr once |
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| 98 | // if order of visit does not change, this should be safe |
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| 99 | void previsit (const ast::UniqueExpr *); |
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| 100 | |
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| 101 | std::unordered_set<decltype(ast::UniqueExpr::id)> visitedIds; |
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| 102 | }; |
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| 103 | |
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| 104 | /// generate temporary ObjectDecls for each argument and return value of each ImplicitCopyCtorExpr, |
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| 105 | /// generate/resolve copy construction expressions for each, and generate/resolve destructors for both |
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| 106 | /// arguments and return value temporaries |
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| 107 | struct ResolveCopyCtors final : public ast::WithGuards, public ast::WithStmtsToAdd<>, public ast::WithSymbolTable, public ast::WithShortCircuiting, public ast::WithVisitorRef<ResolveCopyCtors>, public ast::WithConstTranslationUnit { |
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| 108 | const ast::Expr * postvisit( const ast::ImplicitCopyCtorExpr * impCpCtorExpr ); |
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| 109 | const ast::StmtExpr * previsit( const ast::StmtExpr * stmtExpr ); |
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| 110 | const ast::UniqueExpr * previsit( const ast::UniqueExpr * unqExpr ); |
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| 111 | |
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| 112 | /// handles distant mutations of environment manually. |
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| 113 | /// WithConstTypeSubstitution cannot remember where the environment is from |
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| 114 | |
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| 115 | /// MUST be called at start of overload previsit |
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| 116 | void previsit( const ast::Expr * expr); |
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| 117 | /// MUST be called at return of overload postvisit |
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| 118 | const ast::Expr * postvisit(const ast::Expr * expr); |
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| 119 | |
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| 120 | /// create and resolve ctor/dtor expression: fname(var, [cpArg]) |
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| 121 | const ast::Expr * makeCtorDtor( const std::string & fname, const ast::ObjectDecl * var, const ast::Expr * cpArg = nullptr ); |
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| 122 | /// true if type does not need to be copy constructed to ensure correctness |
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| 123 | bool skipCopyConstruct( const ast::Type * type ); |
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| 124 | ast::ptr< ast::Expr > copyConstructArg( const ast::Expr * arg, const ast::ImplicitCopyCtorExpr * impCpCtorExpr, const ast::Type * formal ); |
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| 125 | ast::Expr * destructRet( const ast::ObjectDecl * ret, const ast::Expr * arg ); |
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| 126 | private: |
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| 127 | /// hack to implement WithTypeSubstitution while conforming to mutation safety. |
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| 128 | ast::TypeSubstitution * env = nullptr; |
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| 129 | bool envModified = false; |
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| 130 | }; |
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| 131 | |
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| 132 | /// collects constructed object decls - used as a base class |
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| 133 | struct ObjDeclCollector : public ast::WithGuards, public ast::WithShortCircuiting { |
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| 134 | // use ordered data structure to maintain ordering for set_difference and for consistent error messages |
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| 135 | typedef std::list< const ast::ObjectDecl * > ObjectSet; |
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| 136 | void previsit( const ast::CompoundStmt *compoundStmt ); |
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| 137 | void previsit( const ast::DeclStmt *stmt ); |
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| 138 | |
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| 139 | // don't go into other functions |
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| 140 | void previsit( const ast::FunctionDecl * ) { visit_children = false; } |
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| 141 | |
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| 142 | protected: |
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| 143 | ObjectSet curVars; |
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| 144 | }; |
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| 145 | |
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| 146 | // debug |
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| 147 | template<typename ObjectSet> |
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| 148 | struct PrintSet { |
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| 149 | PrintSet( const ObjectSet & objs ) : objs( objs ) {} |
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| 150 | const ObjectSet & objs; |
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| 151 | }; |
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| 152 | template<typename ObjectSet> |
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| 153 | PrintSet<ObjectSet> printSet( const ObjectSet & objs ) { return PrintSet<ObjectSet>( objs ); } |
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| 154 | template<typename ObjectSet> |
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| 155 | std::ostream & operator<<( std::ostream & out, const PrintSet<ObjectSet> & set) { |
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| 156 | out << "{ "; |
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| 157 | for ( auto & obj : set.objs ) { |
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| 158 | out << obj->name << ", " ; |
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| 159 | } // for |
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| 160 | out << " }"; |
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| 161 | return out; |
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| 162 | } |
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[0e707bd] | 163 | |
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[17c13b9] | 164 | struct LabelFinder final : public ObjDeclCollector { |
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| 165 | typedef std::map< std::string, ObjectSet > LabelMap; |
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| 166 | // map of Label -> live variables at that label |
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| 167 | LabelMap vars; |
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[0e707bd] | 168 | |
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[17c13b9] | 169 | typedef ObjDeclCollector Parent; |
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| 170 | using Parent::previsit; |
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| 171 | void previsit( const ast::Stmt * stmt ); |
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[0e707bd] | 172 | |
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[17c13b9] | 173 | void previsit( const ast::CompoundStmt *compoundStmt ); |
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| 174 | void previsit( const ast::DeclStmt *stmt ); |
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| 175 | }; |
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[0e707bd] | 176 | |
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[17c13b9] | 177 | /// insert destructor calls at the appropriate places. must happen before CtorInit nodes are removed |
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| 178 | /// (currently by FixInit) |
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| 179 | struct InsertDtors final : public ObjDeclCollector, public ast::WithStmtsToAdd<> { |
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| 180 | InsertDtors( ast::Pass<LabelFinder> & finder ) : finder( finder ), labelVars( finder.core.vars ) {} |
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[0e707bd] | 181 | |
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[17c13b9] | 182 | typedef ObjDeclCollector Parent; |
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| 183 | using Parent::previsit; |
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[490fb92e] | 184 | |
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[17c13b9] | 185 | void previsit( const ast::FunctionDecl * funcDecl ); |
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[0e707bd] | 186 | |
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[17c13b9] | 187 | void previsit( const ast::BranchStmt * stmt ); |
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| 188 | private: |
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| 189 | void handleGoto( const ast::BranchStmt * stmt ); |
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[0e707bd] | 190 | |
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[17c13b9] | 191 | ast::Pass<LabelFinder> & finder; |
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| 192 | LabelFinder::LabelMap & labelVars; |
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| 193 | }; |
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[490fb92e] | 194 | |
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[17c13b9] | 195 | /// expand each object declaration to use its constructor after it is declared. |
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| 196 | struct FixInit : public ast::WithStmtsToAdd<> { |
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| 197 | static void fixInitializers( ast::TranslationUnit &translationUnit ); |
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[490fb92e] | 198 | |
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[17c13b9] | 199 | const ast::DeclWithType * postvisit( const ast::ObjectDecl *objDecl ); |
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[490fb92e] | 200 | |
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[17c13b9] | 201 | std::list< ast::ptr< ast::Decl > > staticDtorDecls; |
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| 202 | }; |
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| 203 | |
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| 204 | /// generate default/copy ctor and dtor calls for user-defined struct ctor/dtors |
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| 205 | /// for any member that is missing a corresponding ctor/dtor call. |
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| 206 | /// error if a member is used before constructed |
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| 207 | struct GenStructMemberCalls final : public ast::WithGuards, public ast::WithShortCircuiting, public ast::WithSymbolTable, public ast::WithVisitorRef<GenStructMemberCalls>, public ast::WithConstTranslationUnit { |
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| 208 | void previsit( const ast::FunctionDecl * funcDecl ); |
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| 209 | const ast::DeclWithType * postvisit( const ast::FunctionDecl * funcDecl ); |
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| 210 | |
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| 211 | void previsit( const ast::MemberExpr * memberExpr ); |
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| 212 | void previsit( const ast::ApplicationExpr * appExpr ); |
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[490fb92e] | 213 | |
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[17c13b9] | 214 | /// Note: this post mutate used to be in a separate visitor. If this pass breaks, one place to examine is whether it is |
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| 215 | /// okay for this part of the recursion to occur alongside the rest. |
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| 216 | const ast::Expr * postvisit( const ast::UntypedExpr * expr ); |
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| 217 | |
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| 218 | SemanticErrorException errors; |
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| 219 | private: |
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| 220 | template< typename... Params > |
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| 221 | void emit( CodeLocation, const Params &... params ); |
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| 222 | |
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| 223 | ast::FunctionDecl * function = nullptr; |
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| 224 | std::set< const ast::DeclWithType * > unhandled; |
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| 225 | std::map< const ast::DeclWithType *, CodeLocation > usedUninit; |
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| 226 | const ast::ObjectDecl * thisParam = nullptr; |
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| 227 | bool isCtor = false; // true if current function is a constructor |
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| 228 | const ast::StructDecl * structDecl = nullptr; |
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| 229 | }; |
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| 230 | |
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| 231 | /// expands ConstructorExpr nodes into comma expressions, using a temporary for the first argument |
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| 232 | struct FixCtorExprs final : public ast::WithDeclsToAdd<>, public ast::WithSymbolTable, public ast::WithShortCircuiting, public ast::WithConstTranslationUnit { |
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| 233 | const ast::Expr * postvisit( const ast::ConstructorExpr * ctorExpr ); |
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| 234 | }; |
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| 235 | |
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| 236 | /// add CompoundStmts around top-level expressions so that temporaries are destroyed in the correct places. |
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| 237 | struct SplitExpressions : public ast::WithShortCircuiting { |
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| 238 | ast::Stmt * postvisit( const ast::ExprStmt * stmt ); |
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| 239 | void previsit( const ast::TupleAssignExpr * expr ); |
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| 240 | }; |
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| 241 | |
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| 242 | /// find and return the destructor used in `input`. If `input` is not a simple destructor call, generate a thunk |
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| 243 | /// that wraps the destructor, insert it into `stmtsToAdd` and return the new function declaration |
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| 244 | const ast::DeclWithType * getDtorFunc( const ast::ObjectDecl * objDecl, const ast::Stmt * input, std::list< ast::ptr<ast::Stmt> > & stmtsToAdd ) { |
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| 245 | const CodeLocation loc = input->location; |
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| 246 | assert( input ); |
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| 247 | auto matches = collectCtorDtorCalls( input ); |
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| 248 | |
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[a4ed165] | 249 | // The simple case requires a direct call and only one destructor call. |
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| 250 | if ( dynamic_cast< const ast::ExprStmt * >( input ) && matches.size() == 1 ) { |
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| 251 | auto func = getFunction( matches.front() ); |
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| 252 | assertf( func, "getFunction failed to find function in %s", toString( matches.front() ).c_str() ); |
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| 253 | |
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| 254 | // cleanup argument must be a function, not an object (including function pointer) |
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| 255 | if ( auto dtorFunc = dynamic_cast< const ast::FunctionDecl * > ( func ) ) { |
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| 256 | if ( dtorFunc->type->forall.empty() ) { |
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| 257 | // simple case where the destructor is a monomorphic function call - can simply |
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| 258 | // use that function as the cleanup function. |
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| 259 | return func; |
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[17c13b9] | 260 | } |
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[490fb92e] | 261 | } |
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[0e707bd] | 262 | } |
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[490fb92e] | 263 | |
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[17c13b9] | 264 | // otherwise the cleanup is more complicated - need to build a single argument cleanup function that |
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| 265 | // wraps the more complicated code. |
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| 266 | static UniqueName dtorNamer( "__cleanup_dtor" ); |
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| 267 | std::string name = dtorNamer.newName(); |
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| 268 | ast::FunctionDecl * dtorFunc = genDefaultFunc( loc, name, objDecl->type->stripReferences(), false ); |
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| 269 | stmtsToAdd.push_back( new ast::DeclStmt(loc, dtorFunc ) ); |
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| 270 | |
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| 271 | // the original code contains uses of objDecl - replace them with the newly generated 'this' parameter. |
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| 272 | const ast::ObjectDecl * thisParam = getParamThis( dtorFunc ); |
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| 273 | const ast::Expr * replacement = new ast::VariableExpr( loc, thisParam ); |
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| 274 | |
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| 275 | auto base = replacement->result->stripReferences(); |
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| 276 | if ( dynamic_cast< const ast::ArrayType * >( base ) || dynamic_cast< const ast::TupleType * > ( base ) ) { |
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| 277 | // need to cast away reference for array types, since the destructor is generated without the reference type, |
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| 278 | // and for tuple types since tuple indexing does not work directly on a reference |
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| 279 | replacement = new ast::CastExpr( replacement, base ); |
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[0e707bd] | 280 | } |
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[17c13b9] | 281 | auto dtor = ast::DeclReplacer::replace( input, ast::DeclReplacer::ExprMap{ std::make_pair( objDecl, replacement ) } ); |
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| 282 | auto mutStmts = dtorFunc->stmts.get_and_mutate(); |
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| 283 | mutStmts->push_back(strict_dynamic_cast<const ast::Stmt *>( dtor )); |
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| 284 | dtorFunc->stmts = mutStmts; |
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[490fb92e] | 285 | |
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[17c13b9] | 286 | return dtorFunc; |
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| 287 | } |
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| 288 | |
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| 289 | void FixInit::fixInitializers( ast::TranslationUnit & translationUnit ) { |
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| 290 | ast::Pass<FixInit> fixer; |
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| 291 | |
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| 292 | // can't use mutateAll, because need to insert declarations at top-level |
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| 293 | // can't use DeclMutator, because sometimes need to insert IfStmt, etc. |
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| 294 | SemanticErrorException errors; |
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| 295 | for ( auto i = translationUnit.decls.begin(); i != translationUnit.decls.end(); ++i ) { |
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| 296 | try { |
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| 297 | *i = (*i)->accept(fixer); |
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| 298 | translationUnit.decls.splice( i, fixer.core.staticDtorDecls ); |
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| 299 | } catch( SemanticErrorException &e ) { |
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| 300 | errors.append( e ); |
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| 301 | } // try |
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| 302 | } // for |
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| 303 | if ( ! errors.isEmpty() ) { |
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| 304 | throw errors; |
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| 305 | } // if |
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| 306 | } |
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| 307 | |
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| 308 | const ast::StmtExpr * StmtExprResult::previsit( const ast::StmtExpr * stmtExpr ) { |
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| 309 | assert( stmtExpr->result ); |
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[a4ed165] | 310 | if ( stmtExpr->result->isVoid() ) return stmtExpr; |
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| 311 | |
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| 312 | auto mutExpr = mutate( stmtExpr ); |
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| 313 | const ast::CompoundStmt * body = mutExpr->stmts; |
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| 314 | assert( !body->kids.empty() ); |
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| 315 | mutExpr->resultExpr = body->kids.back().strict_as<ast::ExprStmt>(); |
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| 316 | return mutExpr; |
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[17c13b9] | 317 | } |
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[490fb92e] | 318 | |
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[17c13b9] | 319 | ast::Stmt * SplitExpressions::postvisit( const ast::ExprStmt * stmt ) { |
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| 320 | // wrap each top-level ExprStmt in a block so that destructors for argument and return temporaries are destroyed |
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| 321 | // in the correct places |
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[a4ed165] | 322 | return new ast::CompoundStmt( stmt->location, { stmt } ); |
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[17c13b9] | 323 | } |
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| 324 | |
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| 325 | void SplitExpressions::previsit( const ast::TupleAssignExpr * ) { |
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| 326 | // don't do this within TupleAssignExpr, since it is already broken up into multiple expressions |
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| 327 | visit_children = false; |
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| 328 | } |
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[490fb92e] | 329 | |
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[17c13b9] | 330 | // Relatively simple structural comparison for expressions, needed to determine |
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| 331 | // if two expressions are "the same" (used to determine if self assignment occurs) |
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| 332 | struct StructuralChecker { |
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| 333 | // Strip all casts and then dynamic_cast. |
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| 334 | template<typename T> |
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| 335 | static const T * cast( const ast::Expr * expr ) { |
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| 336 | // this might be too permissive. It's possible that only particular casts are relevant. |
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| 337 | while ( auto cast = dynamic_cast< const ast::CastExpr * >( expr ) ) { |
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| 338 | expr = cast->arg; |
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[0e707bd] | 339 | } |
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[17c13b9] | 340 | return dynamic_cast< const T * >( expr ); |
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| 341 | } |
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[490fb92e] | 342 | |
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[17c13b9] | 343 | void previsit( const ast::Expr * ) { |
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| 344 | // anything else does not qualify |
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| 345 | result = false; |
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| 346 | } |
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[0e707bd] | 347 | |
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[17c13b9] | 348 | // ignore casts |
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| 349 | void previsit( const ast::CastExpr * ) {} |
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[490fb92e] | 350 | |
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[17c13b9] | 351 | void previsit( const ast::MemberExpr * memExpr ) { |
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| 352 | if ( auto otherMember = cast< ast::MemberExpr >( other ) ) { |
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| 353 | if ( otherMember->member == memExpr->member ) { |
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| 354 | other = otherMember->aggregate; |
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| 355 | return; |
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[490fb92e] | 356 | } |
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[0e707bd] | 357 | } |
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[17c13b9] | 358 | result = false; |
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| 359 | } |
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[490fb92e] | 360 | |
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[17c13b9] | 361 | void previsit( const ast::VariableExpr * varExpr ) { |
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| 362 | if ( auto otherVar = cast< ast::VariableExpr >( other ) ) { |
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| 363 | if ( otherVar->var == varExpr->var ) { |
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[0e707bd] | 364 | return; |
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| 365 | } |
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[490fb92e] | 366 | } |
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[17c13b9] | 367 | result = false; |
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[0e707bd] | 368 | } |
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| 369 | |
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[17c13b9] | 370 | void previsit( const ast::AddressExpr * ) { |
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| 371 | if ( auto addrExpr = cast< ast::AddressExpr >( other ) ) { |
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| 372 | other = addrExpr->arg; |
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| 373 | return; |
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[490fb92e] | 374 | } |
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[17c13b9] | 375 | result = false; |
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[0e707bd] | 376 | } |
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[490fb92e] | 377 | |
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[17c13b9] | 378 | const ast::Expr * other; |
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| 379 | bool result = true; |
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| 380 | StructuralChecker( const ast::Expr * other ) : other(other) {} |
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| 381 | }; |
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| 382 | |
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| 383 | bool structurallySimilar( const ast::Expr * e1, const ast::Expr * e2 ) { |
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| 384 | return ast::Pass<StructuralChecker>::read( e1, e2 ); |
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| 385 | } |
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| 386 | |
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| 387 | void SelfAssignChecker::previsit( const ast::ApplicationExpr * appExpr ) { |
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| 388 | auto function = getFunction( appExpr ); |
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| 389 | // Doesn't use isAssignment, because ?+=?, etc. should not count as self-assignment. |
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| 390 | if ( function->name == "?=?" && appExpr->args.size() == 2 |
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| 391 | // Check for structural similarity (same variable use, ignore casts, etc. |
---|
| 392 | // (but does not look too deeply, anything looking like a function is off limits). |
---|
| 393 | && structurallySimilar( appExpr->args.front(), appExpr->args.back() ) ) { |
---|
| 394 | SemanticWarning( appExpr->location, Warning::SelfAssignment, toCString( appExpr->args.front() ) ); |
---|
| 395 | } |
---|
| 396 | } |
---|
| 397 | |
---|
| 398 | const ast::Expr * InsertImplicitCalls::postvisit( const ast::ApplicationExpr * appExpr ) { |
---|
| 399 | if ( auto function = appExpr->func.as<ast::VariableExpr>() ) { |
---|
| 400 | if ( function->var->linkage.is_builtin ) { |
---|
| 401 | // optimization: don't need to copy construct in order to call intrinsic functions |
---|
| 402 | return appExpr; |
---|
| 403 | } else if ( auto funcDecl = function->var.as<ast::DeclWithType>() ) { |
---|
| 404 | auto ftype = dynamic_cast< const ast::FunctionType * >( GenPoly::getFunctionType( funcDecl->get_type() ) ); |
---|
| 405 | assertf( ftype, "Function call without function type: %s", toString( funcDecl ).c_str() ); |
---|
| 406 | if ( CodeGen::isConstructor( funcDecl->name ) && ftype->params.size() == 2 ) { |
---|
| 407 | auto t1 = getPointerBase( ftype->params.front() ); |
---|
| 408 | auto t2 = ftype->params.back(); |
---|
| 409 | assert( t1 ); |
---|
| 410 | |
---|
| 411 | if ( ResolvExpr::typesCompatible( t1, t2 ) ) { |
---|
| 412 | // optimization: don't need to copy construct in order to call a copy constructor |
---|
[0e707bd] | 413 | return appExpr; |
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[490fb92e] | 414 | } // if |
---|
[17c13b9] | 415 | } else if ( CodeGen::isDestructor( funcDecl->name ) ) { |
---|
| 416 | // correctness: never copy construct arguments to a destructor |
---|
| 417 | return appExpr; |
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[490fb92e] | 418 | } // if |
---|
[0e707bd] | 419 | } // if |
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[17c13b9] | 420 | } // if |
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| 421 | CP_CTOR_PRINT( std::cerr << "InsertImplicitCalls: adding a wrapper " << appExpr << std::endl; ) |
---|
| 422 | |
---|
| 423 | // wrap each function call so that it is easy to identify nodes that have to be copy constructed |
---|
| 424 | ast::ptr<ast::TypeSubstitution> tmp = appExpr->env; |
---|
| 425 | auto mutExpr = mutate(appExpr); |
---|
| 426 | mutExpr->env = nullptr; |
---|
| 427 | |
---|
| 428 | auto expr = new ast::ImplicitCopyCtorExpr( appExpr->location, mutExpr ); |
---|
| 429 | // Move the type substitution to the new top-level. The substitution |
---|
| 430 | // is needed to obtain the type of temporary variables so that copy |
---|
| 431 | // constructor calls can be resolved. |
---|
| 432 | expr->env = tmp; |
---|
| 433 | return expr; |
---|
| 434 | } |
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[490fb92e] | 435 | |
---|
[17c13b9] | 436 | void ResolveCopyCtors::previsit(const ast::Expr * expr) { |
---|
| 437 | if ( nullptr == expr->env ) { |
---|
| 438 | return; |
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[0e707bd] | 439 | } |
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[17c13b9] | 440 | GuardValue( env ) = expr->env->clone(); |
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| 441 | GuardValue( envModified ) = false; |
---|
| 442 | } |
---|
[490fb92e] | 443 | |
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[17c13b9] | 444 | const ast::Expr * ResolveCopyCtors::postvisit(const ast::Expr * expr) { |
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| 445 | // No local environment, skip. |
---|
| 446 | if ( nullptr == expr->env ) { |
---|
| 447 | return expr; |
---|
| 448 | // Environment was modified, mutate and replace. |
---|
| 449 | } else if ( envModified ) { |
---|
| 450 | auto mutExpr = mutate(expr); |
---|
| 451 | mutExpr->env = env; |
---|
| 452 | return mutExpr; |
---|
| 453 | // Environment was not mutated, delete the shallow copy before guard. |
---|
| 454 | } else { |
---|
| 455 | delete env; |
---|
| 456 | return expr; |
---|
[0e707bd] | 457 | } |
---|
[17c13b9] | 458 | } |
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[490fb92e] | 459 | |
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[17c13b9] | 460 | bool ResolveCopyCtors::skipCopyConstruct( const ast::Type * type ) { return ! isConstructable( type ); } |
---|
| 461 | |
---|
| 462 | const ast::Expr * ResolveCopyCtors::makeCtorDtor( const std::string & fname, const ast::ObjectDecl * var, const ast::Expr * cpArg ) { |
---|
| 463 | assert( var ); |
---|
| 464 | assert( var->isManaged() ); |
---|
| 465 | assert( !cpArg || cpArg->isManaged() ); |
---|
| 466 | // arrays are not copy constructed, so this should always be an ExprStmt |
---|
| 467 | ast::ptr< ast::Stmt > stmt = genCtorDtor(var->location, fname, var, cpArg ); |
---|
| 468 | assertf( stmt, "ResolveCopyCtors: genCtorDtor returned nullptr: %s / %s / %s", fname.c_str(), toString( var ).c_str(), toString( cpArg ).c_str() ); |
---|
| 469 | auto exprStmt = stmt.strict_as<ast::ImplicitCtorDtorStmt>()->callStmt.strict_as<ast::ExprStmt>(); |
---|
| 470 | ast::ptr<ast::Expr> untyped = exprStmt->expr; // take ownership of expr |
---|
| 471 | |
---|
| 472 | // resolve copy constructor |
---|
| 473 | // should only be one alternative for copy ctor and dtor expressions, since all arguments are fixed |
---|
| 474 | // (VariableExpr and already resolved expression) |
---|
| 475 | CP_CTOR_PRINT( std::cerr << "ResolvingCtorDtor " << untyped << std::endl; ) |
---|
| 476 | ast::ptr<ast::Expr> resolved = ResolvExpr::findVoidExpression(untyped, { symtab, transUnit().global } ); |
---|
| 477 | assert( resolved ); |
---|
| 478 | if ( resolved->env ) { |
---|
| 479 | // Extract useful information and discard new environments. Keeping them causes problems in PolyMutator passes. |
---|
| 480 | env->add( *resolved->env ); |
---|
| 481 | envModified = true; |
---|
| 482 | auto mut = mutate(resolved.get()); |
---|
| 483 | assertf(mut == resolved.get(), "newly resolved expression must be unique"); |
---|
| 484 | mut->env = nullptr; |
---|
| 485 | } // if |
---|
| 486 | if ( auto assign = resolved.as<ast::TupleAssignExpr>() ) { |
---|
| 487 | // fix newly generated StmtExpr |
---|
| 488 | previsit( assign->stmtExpr ); |
---|
[0e707bd] | 489 | } |
---|
[17c13b9] | 490 | return resolved.release(); |
---|
| 491 | } |
---|
[490fb92e] | 492 | |
---|
[17c13b9] | 493 | ast::ptr<ast::Expr> ResolveCopyCtors::copyConstructArg( |
---|
| 494 | const ast::Expr * arg, const ast::ImplicitCopyCtorExpr * impCpCtorExpr, const ast::Type * formal ) |
---|
| 495 | { |
---|
| 496 | static UniqueName tempNamer("_tmp_cp"); |
---|
| 497 | const CodeLocation loc = impCpCtorExpr->location; |
---|
| 498 | // CP_CTOR_PRINT( std::cerr << "Type Substitution: " << *env << std::endl; ) |
---|
| 499 | assert( arg->result ); |
---|
| 500 | ast::ptr<ast::Type> result = arg->result; |
---|
| 501 | if ( skipCopyConstruct( result ) ) return arg; // skip certain non-copyable types |
---|
| 502 | |
---|
| 503 | // type may involve type variables, so apply type substitution to get temporary variable's actual type, |
---|
| 504 | // since result type may not be substituted (e.g., if the type does not appear in the parameter list) |
---|
| 505 | // Use applyFree so that types bound in function pointers are not substituted, e.g. in forall(dtype T) void (*)(T). |
---|
| 506 | |
---|
| 507 | // xxx - this originally mutates arg->result in place. is it correct? |
---|
| 508 | assert( env ); |
---|
| 509 | result = env->applyFree( result.get() ).node; |
---|
| 510 | auto mutResult = result.get_and_mutate(); |
---|
| 511 | mutResult->set_const(false); |
---|
| 512 | |
---|
| 513 | auto mutArg = mutate(arg); |
---|
| 514 | mutArg->result = mutResult; |
---|
| 515 | |
---|
| 516 | ast::ptr<ast::Expr> guard = mutArg; |
---|
| 517 | |
---|
| 518 | ast::ptr<ast::ObjectDecl> tmp = new ast::ObjectDecl(loc, "__tmp", mutResult, nullptr ); |
---|
| 519 | |
---|
| 520 | // create and resolve copy constructor |
---|
| 521 | CP_CTOR_PRINT( std::cerr << "makeCtorDtor for an argument" << std::endl; ) |
---|
| 522 | auto cpCtor = makeCtorDtor( "?{}", tmp, mutArg ); |
---|
| 523 | |
---|
| 524 | if ( auto appExpr = dynamic_cast< const ast::ApplicationExpr * >( cpCtor ) ) { |
---|
| 525 | // if the chosen constructor is intrinsic, the copy is unnecessary, so |
---|
| 526 | // don't create the temporary and don't call the copy constructor |
---|
| 527 | auto function = appExpr->func.strict_as<ast::VariableExpr>(); |
---|
| 528 | if ( function->var->linkage == ast::Linkage::Intrinsic ) { |
---|
| 529 | // arguments that need to be boxed need a temporary regardless of whether the copy constructor is intrinsic, |
---|
| 530 | // so that the object isn't changed inside of the polymorphic function |
---|
| 531 | if ( ! GenPoly::needsBoxing( formal, result, impCpCtorExpr->callExpr, env ) ) { |
---|
| 532 | // xxx - should arg->result be mutated? see comment above. |
---|
| 533 | return guard; |
---|
[490fb92e] | 534 | } |
---|
[0e707bd] | 535 | } |
---|
[17c13b9] | 536 | } |
---|
[490fb92e] | 537 | |
---|
[17c13b9] | 538 | // set a unique name for the temporary once it's certain the call is necessary |
---|
| 539 | auto mut = tmp.get_and_mutate(); |
---|
| 540 | assertf (mut == tmp, "newly created ObjectDecl must be unique"); |
---|
| 541 | mut->name = tempNamer.newName(); |
---|
[490fb92e] | 542 | |
---|
[17c13b9] | 543 | // replace argument to function call with temporary |
---|
| 544 | stmtsToAddBefore.push_back( new ast::DeclStmt(loc, tmp ) ); |
---|
| 545 | arg = cpCtor; |
---|
| 546 | return destructRet( tmp, arg ); |
---|
| 547 | } |
---|
[490fb92e] | 548 | |
---|
[17c13b9] | 549 | ast::Expr * ResolveCopyCtors::destructRet( const ast::ObjectDecl * ret, const ast::Expr * arg ) { |
---|
| 550 | auto global = transUnit().global; |
---|
| 551 | // TODO: refactor code for generating cleanup attribute, since it's common and reused in ~3-4 places |
---|
| 552 | // check for existing cleanup attribute before adding another(?) |
---|
| 553 | // need to add __Destructor for _tmp_cp variables as well |
---|
[490fb92e] | 554 | |
---|
[17c13b9] | 555 | assertf( global.dtorStruct, "Destructor generation requires __Destructor definition." ); |
---|
| 556 | assertf( global.dtorStruct->members.size() == 2, "__Destructor definition does not have expected fields." ); |
---|
| 557 | assertf( global.dtorDestroy, "Destructor generation requires __destroy_Destructor." ); |
---|
[490fb92e] | 558 | |
---|
[4c0fa03] | 559 | const CodeLocation & loc = ret->location; |
---|
[490fb92e] | 560 | |
---|
[17c13b9] | 561 | // generate a __Destructor for ret that calls the destructor |
---|
| 562 | auto res = makeCtorDtor( "^?{}", ret ); |
---|
| 563 | auto dtor = mutate(res); |
---|
[490fb92e] | 564 | |
---|
[17c13b9] | 565 | // if the chosen destructor is intrinsic, elide the generated dtor handler |
---|
| 566 | if ( arg && isIntrinsicCallExpr( dtor ) ) { |
---|
| 567 | return new ast::CommaExpr(loc, arg, new ast::VariableExpr(loc, ret ) ); |
---|
| 568 | } |
---|
[490fb92e] | 569 | |
---|
[5bf685f] | 570 | if ( nullptr == dtor->env && nullptr != env ) { |
---|
| 571 | dtor->env = ast::shallowCopy( env ); |
---|
| 572 | } |
---|
[17c13b9] | 573 | auto dtorFunc = getDtorFunc( ret, new ast::ExprStmt(loc, dtor ), stmtsToAddBefore ); |
---|
[490fb92e] | 574 | |
---|
[17c13b9] | 575 | auto dtorStructType = new ast::StructInstType( global.dtorStruct ); |
---|
[490fb92e] | 576 | |
---|
[17c13b9] | 577 | // what does this do??? |
---|
| 578 | dtorStructType->params.push_back( new ast::TypeExpr(loc, new ast::VoidType() ) ); |
---|
[490fb92e] | 579 | |
---|
[17c13b9] | 580 | // cast destructor pointer to void (*)(void *), to silence GCC incompatible pointer warnings |
---|
| 581 | auto dtorFtype = new ast::FunctionType(); |
---|
| 582 | dtorFtype->params.push_back( new ast::PointerType(new ast::VoidType( ) ) ); |
---|
| 583 | auto dtorType = new ast::PointerType( dtorFtype ); |
---|
[490fb92e] | 584 | |
---|
[17c13b9] | 585 | static UniqueName namer( "_ret_dtor" ); |
---|
| 586 | auto retDtor = new ast::ObjectDecl(loc, namer.newName(), dtorStructType, new ast::ListInit(loc, { new ast::SingleInit(loc, ast::ConstantExpr::null(loc) ), new ast::SingleInit(loc, new ast::CastExpr( new ast::VariableExpr(loc, dtorFunc ), dtorType ) ) } ) ); |
---|
| 587 | retDtor->attributes.push_back( new ast::Attribute( "cleanup", { new ast::VariableExpr(loc, global.dtorDestroy ) } ) ); |
---|
| 588 | stmtsToAddBefore.push_back( new ast::DeclStmt(loc, retDtor ) ); |
---|
[490fb92e] | 589 | |
---|
[17c13b9] | 590 | if ( arg ) { |
---|
| 591 | auto member = new ast::MemberExpr(loc, global.dtorStruct->members.front().strict_as<ast::DeclWithType>(), new ast::VariableExpr(loc, retDtor ) ); |
---|
| 592 | auto object = new ast::CastExpr( new ast::AddressExpr( new ast::VariableExpr(loc, ret ) ), new ast::PointerType(new ast::VoidType() ) ); |
---|
| 593 | ast::Expr * assign = createBitwiseAssignment( member, object ); |
---|
| 594 | return new ast::CommaExpr(loc, new ast::CommaExpr(loc, arg, assign ), new ast::VariableExpr(loc, ret ) ); |
---|
[0e707bd] | 595 | } |
---|
[17c13b9] | 596 | return nullptr; |
---|
| 597 | } |
---|
[490fb92e] | 598 | |
---|
[17c13b9] | 599 | const ast::Expr * ResolveCopyCtors::postvisit( const ast::ImplicitCopyCtorExpr *impCpCtorExpr ) { |
---|
| 600 | CP_CTOR_PRINT( std::cerr << "ResolveCopyCtors: " << impCpCtorExpr << std::endl; ) |
---|
| 601 | |
---|
| 602 | ast::ApplicationExpr * appExpr = mutate(impCpCtorExpr->callExpr.get()); |
---|
| 603 | const ast::ObjectDecl * returnDecl = nullptr; |
---|
| 604 | const CodeLocation loc = appExpr->location; |
---|
| 605 | |
---|
| 606 | // take each argument and attempt to copy construct it. |
---|
| 607 | auto ftype = GenPoly::getFunctionType( appExpr->func->result ); |
---|
| 608 | assert( ftype ); |
---|
| 609 | auto & params = ftype->params; |
---|
| 610 | auto iter = params.begin(); |
---|
| 611 | for ( auto & arg : appExpr->args ) { |
---|
| 612 | const ast::Type * formal = nullptr; |
---|
[a4ed165] | 613 | // Do not copy construct C-style variadic arguments. |
---|
| 614 | if ( iter != params.end() ) { |
---|
[17c13b9] | 615 | formal = *iter++; |
---|
| 616 | } |
---|
[490fb92e] | 617 | |
---|
[17c13b9] | 618 | arg = copyConstructArg( arg, impCpCtorExpr, formal ); |
---|
| 619 | } // for |
---|
| 620 | |
---|
| 621 | // each return value from the call needs to be connected with an ObjectDecl at the call site, which is |
---|
| 622 | // initialized with the return value and is destructed later |
---|
| 623 | // xxx - handle named return values? |
---|
| 624 | const ast::Type * result = appExpr->result; |
---|
| 625 | if ( ! result->isVoid() ) { |
---|
| 626 | static UniqueName retNamer("_tmp_cp_ret"); |
---|
| 627 | auto subResult = env->apply( result ).node; |
---|
| 628 | auto ret = new ast::ObjectDecl(loc, retNamer.newName(), subResult, nullptr ); |
---|
| 629 | auto mutType = mutate(ret->type.get()); |
---|
| 630 | mutType->set_const( false ); |
---|
| 631 | ret->type = mutType; |
---|
| 632 | returnDecl = ret; |
---|
| 633 | stmtsToAddBefore.push_back( new ast::DeclStmt(loc, ret ) ); |
---|
| 634 | CP_CTOR_PRINT( std::cerr << "makeCtorDtor for a return" << std::endl; ) |
---|
| 635 | } // for |
---|
| 636 | CP_CTOR_PRINT( std::cerr << "after Resolving: " << impCpCtorExpr << std::endl; ) |
---|
| 637 | // ------------------------------------------------------ |
---|
| 638 | |
---|
| 639 | CP_CTOR_PRINT( std::cerr << "Coming out the back..." << impCpCtorExpr << std::endl; ) |
---|
| 640 | |
---|
| 641 | // detach fields from wrapper node so that it can be deleted without deleting too much |
---|
| 642 | |
---|
| 643 | // xxx - actual env might be somewhere else, need to keep invariant |
---|
| 644 | |
---|
| 645 | // deletion of wrapper should be handled by pass template now |
---|
| 646 | |
---|
| 647 | assert (appExpr->env == nullptr); |
---|
| 648 | appExpr->env = impCpCtorExpr->env; |
---|
| 649 | |
---|
| 650 | if ( returnDecl ) { |
---|
| 651 | ast::Expr * assign = createBitwiseAssignment( new ast::VariableExpr(loc, returnDecl ), appExpr ); |
---|
| 652 | if ( ! dynamic_cast< const ast::ReferenceType * >( result ) ) { |
---|
| 653 | // destructing reference returns is bad because it can cause multiple destructor calls to the same object - the returned object is not a temporary |
---|
| 654 | assign = destructRet( returnDecl, assign ); |
---|
| 655 | assert(assign); |
---|
[0e707bd] | 656 | } else { |
---|
[17c13b9] | 657 | assign = new ast::CommaExpr(loc, assign, new ast::VariableExpr(loc, returnDecl ) ); |
---|
| 658 | } |
---|
| 659 | // move env from appExpr to retExpr |
---|
| 660 | assign->env = appExpr->env; |
---|
| 661 | // actual env is handled by common routine that replaces WithTypeSubstitution |
---|
| 662 | return postvisit((const ast::Expr *)assign); |
---|
| 663 | } else { |
---|
| 664 | return postvisit((const ast::Expr *)appExpr); |
---|
| 665 | } // if |
---|
| 666 | } |
---|
[490fb92e] | 667 | |
---|
[17c13b9] | 668 | const ast::StmtExpr * ResolveCopyCtors::previsit( const ast::StmtExpr * _stmtExpr ) { |
---|
| 669 | // function call temporaries should be placed at statement-level, rather than nested inside of a new statement expression, |
---|
| 670 | // since temporaries can be shared across sub-expressions, e.g. |
---|
| 671 | // [A, A] f(); // decl |
---|
| 672 | // g([A] x, [A] y); // decl |
---|
| 673 | // g(f()); // call |
---|
| 674 | // f is executed once, so the return temporary is shared across the tuple constructors for x and y. |
---|
| 675 | // Explicitly mutating children instead of mutating the inner compound statement forces the temporaries to be added |
---|
| 676 | // to the outer context, rather than inside of the statement expression. |
---|
| 677 | |
---|
| 678 | // call the common routine that replaces WithTypeSubstitution |
---|
| 679 | previsit((const ast::Expr *) _stmtExpr); |
---|
| 680 | |
---|
| 681 | visit_children = false; |
---|
| 682 | const CodeLocation loc = _stmtExpr->location; |
---|
| 683 | |
---|
| 684 | assert( env ); |
---|
| 685 | |
---|
| 686 | symtab.enterScope(); |
---|
| 687 | // visit all statements |
---|
| 688 | auto stmtExpr = mutate(_stmtExpr); |
---|
| 689 | auto mutStmts = mutate(stmtExpr->stmts.get()); |
---|
| 690 | |
---|
| 691 | auto & stmts = mutStmts->kids; |
---|
| 692 | for ( auto & stmt : stmts ) { |
---|
| 693 | stmt = stmt->accept( *visitor ); |
---|
| 694 | } // for |
---|
| 695 | stmtExpr->stmts = mutStmts; |
---|
| 696 | symtab.leaveScope(); |
---|
| 697 | |
---|
| 698 | assert( stmtExpr->result ); |
---|
[a4ed165] | 699 | if ( stmtExpr->result->isVoid() ) { |
---|
| 700 | assert( stmtExpr->returnDecls.empty() ); |
---|
| 701 | assert( stmtExpr->dtors.empty() ); |
---|
[0e707bd] | 702 | |
---|
[a4ed165] | 703 | return stmtExpr; |
---|
| 704 | } |
---|
[0e707bd] | 705 | |
---|
[a4ed165] | 706 | static UniqueName retNamer("_tmp_stmtexpr_ret"); |
---|
[490fb92e] | 707 | |
---|
[a4ed165] | 708 | auto result = env->apply( stmtExpr->result.get() ).node; |
---|
| 709 | if ( ! InitTweak::isConstructable( result ) ) { |
---|
| 710 | return stmtExpr; |
---|
| 711 | } |
---|
| 712 | auto mutResult = result.get_and_mutate(); |
---|
| 713 | mutResult->set_const(false); |
---|
[490fb92e] | 714 | |
---|
[a4ed165] | 715 | // create variable that will hold the result of the stmt expr |
---|
| 716 | auto ret = new ast::ObjectDecl(loc, retNamer.newName(), mutResult, nullptr ); |
---|
| 717 | stmtsToAddBefore.push_back( new ast::DeclStmt(loc, ret ) ); |
---|
[490fb92e] | 718 | |
---|
[a4ed165] | 719 | assertf( |
---|
| 720 | stmtExpr->resultExpr, |
---|
| 721 | "Statement-Expression should have a resulting expression at %s:%d", |
---|
| 722 | stmtExpr->location.filename.c_str(), |
---|
| 723 | stmtExpr->location.first_line |
---|
| 724 | ); |
---|
| 725 | |
---|
| 726 | const ast::ExprStmt * last = stmtExpr->resultExpr; |
---|
| 727 | // xxx - if this is non-unique, need to copy while making resultExpr ref |
---|
| 728 | assertf(last->unique(), "attempt to modify weakly shared statement"); |
---|
| 729 | auto mutLast = mutate(last); |
---|
| 730 | // above assertion means in-place mutation is OK |
---|
| 731 | try { |
---|
| 732 | mutLast->expr = makeCtorDtor( "?{}", ret, mutLast->expr ); |
---|
| 733 | } catch(...) { |
---|
| 734 | std::cerr << "*CFA internal error: "; |
---|
| 735 | std::cerr << "can't resolve implicit constructor"; |
---|
| 736 | std::cerr << " at " << stmtExpr->location.filename; |
---|
| 737 | std::cerr << ":" << stmtExpr->location.first_line << std::endl; |
---|
| 738 | |
---|
| 739 | abort(); |
---|
| 740 | } |
---|
| 741 | |
---|
| 742 | // add destructors after current statement |
---|
| 743 | stmtsToAddAfter.push_back( new ast::ExprStmt(loc, makeCtorDtor( "^?{}", ret ) ) ); |
---|
| 744 | |
---|
| 745 | // must have a non-empty body, otherwise it wouldn't have a result |
---|
| 746 | assert( ! stmts.empty() ); |
---|
| 747 | |
---|
| 748 | // if there is a return decl, add a use as the last statement; will not have return decl on non-constructable returns |
---|
| 749 | stmts.push_back( new ast::ExprStmt(loc, new ast::VariableExpr(loc, ret ) ) ); |
---|
[490fb92e] | 750 | |
---|
[17c13b9] | 751 | assert( stmtExpr->returnDecls.empty() ); |
---|
| 752 | assert( stmtExpr->dtors.empty() ); |
---|
[490fb92e] | 753 | |
---|
[17c13b9] | 754 | return stmtExpr; |
---|
| 755 | } |
---|
[490fb92e] | 756 | |
---|
[17c13b9] | 757 | // to prevent warnings ('_unq0' may be used uninitialized in this function), |
---|
| 758 | // insert an appropriate zero initializer for UniqueExpr temporaries. |
---|
| 759 | ast::Init * makeInit( const ast::Type * t, CodeLocation const & loc ) { |
---|
| 760 | if ( auto inst = dynamic_cast< const ast::StructInstType * >( t ) ) { |
---|
| 761 | // initizer for empty struct must be empty |
---|
| 762 | if ( inst->base->members.empty() ) { |
---|
| 763 | return new ast::ListInit( loc, {} ); |
---|
| 764 | } |
---|
| 765 | } else if ( auto inst = dynamic_cast< const ast::UnionInstType * >( t ) ) { |
---|
| 766 | // initizer for empty union must be empty |
---|
| 767 | if ( inst->base->members.empty() ) { |
---|
| 768 | return new ast::ListInit( loc, {} ); |
---|
| 769 | } |
---|
[0e707bd] | 770 | } |
---|
[490fb92e] | 771 | |
---|
[17c13b9] | 772 | return new ast::ListInit( loc, { |
---|
| 773 | new ast::SingleInit( loc, ast::ConstantExpr::from_int( loc, 0 ) ) |
---|
| 774 | } ); |
---|
| 775 | } |
---|
[0e707bd] | 776 | |
---|
[17c13b9] | 777 | const ast::UniqueExpr * ResolveCopyCtors::previsit( const ast::UniqueExpr * unqExpr ) { |
---|
| 778 | visit_children = false; |
---|
| 779 | // xxx - hack to prevent double-handling of unique exprs, otherwise too many temporary variables and destructors are generated |
---|
| 780 | static std::unordered_map< int, const ast::UniqueExpr * > unqMap; |
---|
| 781 | auto mutExpr = mutate(unqExpr); |
---|
| 782 | if ( ! unqMap.count( unqExpr->id ) ) { |
---|
| 783 | auto impCpCtorExpr = mutExpr->expr.as<ast::ImplicitCopyCtorExpr>(); |
---|
| 784 | mutExpr->expr = mutExpr->expr->accept( *visitor ); |
---|
| 785 | // it should never be necessary to wrap a void-returning expression in a UniqueExpr - if this assumption changes, this needs to be rethought |
---|
| 786 | assert( unqExpr->result ); |
---|
| 787 | if ( impCpCtorExpr ) { |
---|
| 788 | auto comma = unqExpr->expr.strict_as<ast::CommaExpr>(); |
---|
| 789 | auto var = comma->arg2.strict_as<ast::VariableExpr>(); |
---|
| 790 | // note the variable used as the result from the call |
---|
| 791 | mutExpr->var = var; |
---|
[0e707bd] | 792 | } else { |
---|
[17c13b9] | 793 | // expr isn't a call expr, so create a new temporary variable to use to hold the value of the unique expression |
---|
| 794 | mutExpr->object = new ast::ObjectDecl( mutExpr->location, toString("_unq", mutExpr->id), mutExpr->result, makeInit( mutExpr->result, mutExpr->location ) ); |
---|
| 795 | mutExpr->var = new ast::VariableExpr( mutExpr->location, mutExpr->object ); |
---|
[490fb92e] | 796 | } |
---|
[17c13b9] | 797 | |
---|
| 798 | unqMap[mutExpr->id] = mutExpr; |
---|
| 799 | } else { |
---|
| 800 | // take data from other UniqueExpr to ensure consistency |
---|
| 801 | mutExpr->expr = unqMap[mutExpr->id]->expr; |
---|
| 802 | mutExpr->result = mutExpr->expr->result; |
---|
[0e707bd] | 803 | } |
---|
[17c13b9] | 804 | return mutExpr; |
---|
| 805 | } |
---|
[490fb92e] | 806 | |
---|
[17c13b9] | 807 | const ast::DeclWithType * FixInit::postvisit( const ast::ObjectDecl *_objDecl ) { |
---|
| 808 | const CodeLocation loc = _objDecl->location; |
---|
[490fb92e] | 809 | |
---|
[17c13b9] | 810 | // since this removes the init field from objDecl, it must occur after children are mutated (i.e. postvisit) |
---|
[a4ed165] | 811 | ast::ptr<ast::ConstructorInit> ctorInit = _objDecl->init.as<ast::ConstructorInit>(); |
---|
[490fb92e] | 812 | |
---|
[a4ed165] | 813 | if ( nullptr == ctorInit ) return _objDecl; |
---|
[17c13b9] | 814 | |
---|
[a4ed165] | 815 | auto objDecl = mutate(_objDecl); |
---|
| 816 | |
---|
| 817 | // could this be non-unique? |
---|
| 818 | if (objDecl != _objDecl) { |
---|
| 819 | std::cerr << "FixInit: non-unique object decl " << objDecl->location << objDecl->name << std::endl; |
---|
| 820 | } |
---|
| 821 | // a decision should have been made by the resolver, so ctor and init are not both non-NULL |
---|
| 822 | assert( ! ctorInit->ctor || ! ctorInit->init ); |
---|
| 823 | if ( const ast::Stmt * ctor = ctorInit->ctor ) { |
---|
| 824 | if ( objDecl->storage.is_static ) { |
---|
| 825 | addDataSectionAttribute(objDecl); |
---|
| 826 | // originally wanted to take advantage of gcc nested functions, but |
---|
| 827 | // we get memory errors with this approach. To remedy this, the static |
---|
| 828 | // variable is hoisted when the destructor needs to be called. |
---|
| 829 | // |
---|
| 830 | // generate: |
---|
| 831 | // static T __objName_static_varN; |
---|
| 832 | // void __objName_dtor_atexitN() { |
---|
| 833 | // __dtor__...; |
---|
| 834 | // } |
---|
| 835 | // int f(...) { |
---|
| 836 | // ... |
---|
| 837 | // static bool __objName_uninitialized = true; |
---|
| 838 | // if (__objName_uninitialized) { |
---|
| 839 | // __ctor(__objName); |
---|
| 840 | // __objName_uninitialized = false; |
---|
| 841 | // atexit(__objName_dtor_atexitN); |
---|
| 842 | // } |
---|
| 843 | // ... |
---|
| 844 | // } |
---|
| 845 | |
---|
| 846 | static UniqueName dtorCallerNamer( "_dtor_atexit" ); |
---|
| 847 | |
---|
| 848 | // static bool __objName_uninitialized = true |
---|
[7a780ad] | 849 | auto boolType = new ast::BasicType( ast::BasicKind::Bool ); |
---|
[a4ed165] | 850 | auto boolInitExpr = new ast::SingleInit(loc, ast::ConstantExpr::from_int(loc, 1 ) ); |
---|
| 851 | auto isUninitializedVar = new ast::ObjectDecl(loc, objDecl->mangleName + "_uninitialized", boolType, boolInitExpr, ast::Storage::Static, ast::Linkage::Cforall); |
---|
| 852 | isUninitializedVar->fixUniqueId(); |
---|
| 853 | |
---|
| 854 | // __objName_uninitialized = false; |
---|
| 855 | auto setTrue = new ast::UntypedExpr(loc, new ast::NameExpr(loc, "?=?" ) ); |
---|
| 856 | setTrue->args.push_back( new ast::VariableExpr(loc, isUninitializedVar ) ); |
---|
| 857 | setTrue->args.push_back( ast::ConstantExpr::from_int(loc, 0 ) ); |
---|
| 858 | |
---|
| 859 | // generate body of if |
---|
| 860 | auto initStmts = new ast::CompoundStmt(loc); |
---|
| 861 | auto & body = initStmts->kids; |
---|
| 862 | body.push_back( ctor ); |
---|
| 863 | body.push_back( new ast::ExprStmt(loc, setTrue ) ); |
---|
| 864 | |
---|
| 865 | // put it all together |
---|
| 866 | auto ifStmt = new ast::IfStmt(loc, new ast::VariableExpr(loc, isUninitializedVar ), initStmts, 0 ); |
---|
| 867 | stmtsToAddAfter.push_back( new ast::DeclStmt(loc, isUninitializedVar ) ); |
---|
| 868 | stmtsToAddAfter.push_back( ifStmt ); |
---|
| 869 | |
---|
| 870 | const ast::Stmt * dtor = ctorInit->dtor; |
---|
| 871 | if ( dtor ) { |
---|
| 872 | // if the object has a non-trivial destructor, have to |
---|
| 873 | // hoist it and the object into the global space and |
---|
| 874 | // call the destructor function with atexit. |
---|
| 875 | |
---|
| 876 | // void __objName_dtor_atexitN(...) {...} |
---|
| 877 | ast::FunctionDecl * dtorCaller = new ast::FunctionDecl(loc, objDecl->mangleName + dtorCallerNamer.newName(), {}, {}, {}, {}, new ast::CompoundStmt(loc, {dtor}), ast::Storage::Static, ast::Linkage::C ); |
---|
| 878 | dtorCaller->fixUniqueId(); |
---|
| 879 | |
---|
| 880 | // atexit(dtor_atexit); |
---|
| 881 | auto callAtexit = new ast::UntypedExpr(loc, new ast::NameExpr(loc, "atexit" ) ); |
---|
| 882 | callAtexit->args.push_back( new ast::VariableExpr(loc, dtorCaller ) ); |
---|
| 883 | |
---|
| 884 | body.push_back( new ast::ExprStmt(loc, callAtexit ) ); |
---|
| 885 | |
---|
| 886 | // hoist variable and dtor caller decls to list of decls that will be added into global scope |
---|
| 887 | staticDtorDecls.push_back( objDecl ); |
---|
| 888 | staticDtorDecls.push_back( dtorCaller ); |
---|
| 889 | |
---|
| 890 | // need to rename object uniquely since it now appears |
---|
| 891 | // at global scope and there could be multiple function-scoped |
---|
| 892 | // static variables with the same name in different functions. |
---|
| 893 | // Note: it isn't sufficient to modify only the mangleName, because |
---|
| 894 | // then subsequent SymbolTable passes can choke on seeing the object's name |
---|
| 895 | // if another object has the same name and type. An unfortunate side-effect |
---|
| 896 | // of renaming the object is that subsequent NameExprs may fail to resolve, |
---|
| 897 | // but there shouldn't be any remaining past this point. |
---|
| 898 | static UniqueName staticNamer( "_static_var" ); |
---|
| 899 | objDecl->name = objDecl->name + staticNamer.newName(); |
---|
| 900 | objDecl->mangleName = Mangle::mangle( objDecl ); |
---|
| 901 | objDecl->init = nullptr; |
---|
| 902 | |
---|
| 903 | // xxx - temporary hack: need to return a declaration, but want to hoist the current object out of this scope |
---|
| 904 | // create a new object which is never used |
---|
| 905 | static UniqueName dummyNamer( "_dummy" ); |
---|
| 906 | auto dummy = new ast::ObjectDecl(loc, dummyNamer.newName(), new ast::PointerType(new ast::VoidType()), nullptr, ast::Storage::Static, ast::Linkage::Cforall, 0, { new ast::Attribute("unused") } ); |
---|
| 907 | return dummy; |
---|
| 908 | } else { |
---|
| 909 | objDecl->init = nullptr; |
---|
| 910 | return objDecl; |
---|
| 911 | } |
---|
[17c13b9] | 912 | } else { |
---|
[a4ed165] | 913 | auto implicit = strict_dynamic_cast< const ast::ImplicitCtorDtorStmt * > ( ctor ); |
---|
| 914 | auto ctorStmt = implicit->callStmt.as<ast::ExprStmt>(); |
---|
| 915 | const ast::ApplicationExpr * ctorCall = nullptr; |
---|
| 916 | if ( ctorStmt && (ctorCall = isIntrinsicCallExpr( ctorStmt->expr )) && ctorCall->args.size() == 2 ) { |
---|
| 917 | // clean up intrinsic copy constructor calls by making them into SingleInits |
---|
| 918 | const ast::Expr * ctorArg = ctorCall->args.back(); |
---|
| 919 | // ctorCall should be gone afterwards |
---|
| 920 | auto mutArg = mutate(ctorArg); |
---|
| 921 | mutArg->env = ctorCall->env; |
---|
| 922 | objDecl->init = new ast::SingleInit(loc, mutArg ); |
---|
| 923 | } else { |
---|
| 924 | stmtsToAddAfter.push_back( ctor ); |
---|
| 925 | objDecl->init = nullptr; |
---|
| 926 | } |
---|
| 927 | |
---|
| 928 | const ast::Stmt * dtor = ctorInit->dtor; |
---|
| 929 | if ( dtor ) { |
---|
| 930 | auto implicit = strict_dynamic_cast< const ast::ImplicitCtorDtorStmt * >( dtor ); |
---|
| 931 | const ast::Stmt * dtorStmt = implicit->callStmt; |
---|
| 932 | |
---|
| 933 | // don't need to call intrinsic dtor, because it does nothing, but |
---|
| 934 | // non-intrinsic dtors must be called |
---|
| 935 | if ( ! isIntrinsicSingleArgCallStmt( dtorStmt ) ) { |
---|
| 936 | // set dtor location to the object's location for error messages |
---|
| 937 | auto dtorFunc = getDtorFunc( objDecl, dtorStmt, stmtsToAddBefore ); |
---|
| 938 | objDecl->attributes.push_back( new ast::Attribute( "cleanup", { new ast::VariableExpr(loc, dtorFunc ) } ) ); |
---|
| 939 | } // if |
---|
| 940 | } |
---|
[0e707bd] | 941 | } // if |
---|
[a4ed165] | 942 | } else if ( const ast::Init * init = ctorInit->init ) { |
---|
| 943 | objDecl->init = init; |
---|
| 944 | } else { |
---|
| 945 | // no constructor and no initializer, which is okay |
---|
| 946 | objDecl->init = nullptr; |
---|
[17c13b9] | 947 | } // if |
---|
[a4ed165] | 948 | return objDecl; |
---|
[17c13b9] | 949 | } |
---|
[490fb92e] | 950 | |
---|
[17c13b9] | 951 | void ObjDeclCollector::previsit( const ast::CompoundStmt * ) { |
---|
| 952 | GuardValue( curVars ); |
---|
| 953 | } |
---|
[490fb92e] | 954 | |
---|
[17c13b9] | 955 | void ObjDeclCollector::previsit( const ast::DeclStmt * stmt ) { |
---|
| 956 | // keep track of all variables currently in scope |
---|
| 957 | if ( auto objDecl = stmt->decl.as<ast::ObjectDecl>() ) { |
---|
| 958 | curVars.push_back( objDecl ); |
---|
| 959 | } // if |
---|
| 960 | } |
---|
[490fb92e] | 961 | |
---|
[17c13b9] | 962 | void LabelFinder::previsit( const ast::Stmt * stmt ) { |
---|
| 963 | // for each label, remember the variables in scope at that label. |
---|
| 964 | for ( auto l : stmt->labels ) { |
---|
| 965 | vars[l] = curVars; |
---|
| 966 | } // for |
---|
| 967 | } |
---|
[490fb92e] | 968 | |
---|
[17c13b9] | 969 | void LabelFinder::previsit( const ast::CompoundStmt * stmt ) { |
---|
[a4ed165] | 970 | previsit( (const ast::Stmt *)stmt ); |
---|
[17c13b9] | 971 | Parent::previsit( stmt ); |
---|
| 972 | } |
---|
[490fb92e] | 973 | |
---|
[17c13b9] | 974 | void LabelFinder::previsit( const ast::DeclStmt * stmt ) { |
---|
| 975 | previsit( (const ast::Stmt *)stmt ); |
---|
| 976 | Parent::previsit( stmt ); |
---|
| 977 | } |
---|
[490fb92e] | 978 | |
---|
[17c13b9] | 979 | void InsertDtors::previsit( const ast::FunctionDecl * funcDecl ) { |
---|
| 980 | // each function needs to have its own set of labels |
---|
| 981 | GuardValue( labelVars ); |
---|
| 982 | labelVars.clear(); |
---|
| 983 | // LabelFinder does not recurse into FunctionDecl, so need to visit |
---|
| 984 | // its children manually. |
---|
| 985 | if (funcDecl->type) funcDecl->type->accept(finder); |
---|
[a4ed165] | 986 | if (funcDecl->stmts) funcDecl->stmts->accept(finder); |
---|
[17c13b9] | 987 | |
---|
| 988 | // all labels for this function have been collected, insert destructors as appropriate via implicit recursion. |
---|
| 989 | } |
---|
[490fb92e] | 990 | |
---|
[17c13b9] | 991 | // Handle break/continue/goto in the same manner as C++. Basic idea: any objects that are in scope at the |
---|
| 992 | // BranchStmt but not at the labelled (target) statement must be destructed. If there are any objects in scope |
---|
| 993 | // at the target location but not at the BranchStmt then those objects would be uninitialized so notify the user |
---|
| 994 | // of the error. See C++ Reference 6.6 Jump Statements for details. |
---|
| 995 | void InsertDtors::handleGoto( const ast::BranchStmt * stmt ) { |
---|
| 996 | // can't do anything for computed goto |
---|
| 997 | if ( stmt->computedTarget ) return; |
---|
| 998 | |
---|
| 999 | assertf( stmt->target.name != "", "BranchStmt missing a label: %s", toString( stmt ).c_str() ); |
---|
| 1000 | // S_L = lvars = set of objects in scope at label definition |
---|
| 1001 | // S_G = curVars = set of objects in scope at goto statement |
---|
| 1002 | ObjectSet & lvars = labelVars[ stmt->target ]; |
---|
| 1003 | |
---|
| 1004 | DTOR_PRINT( |
---|
| 1005 | std::cerr << "at goto label: " << stmt->target.name << std::endl; |
---|
| 1006 | std::cerr << "S_G = " << printSet( curVars ) << std::endl; |
---|
| 1007 | std::cerr << "S_L = " << printSet( lvars ) << std::endl; |
---|
| 1008 | ) |
---|
| 1009 | |
---|
| 1010 | |
---|
| 1011 | // std::set_difference requires that the inputs be sorted. |
---|
| 1012 | lvars.sort(); |
---|
| 1013 | curVars.sort(); |
---|
| 1014 | |
---|
| 1015 | ObjectSet diff; |
---|
| 1016 | // S_L-S_G results in set of objects whose construction is skipped - it's an error if this set is non-empty |
---|
| 1017 | std::set_difference( lvars.begin(), lvars.end(), curVars.begin(), curVars.end(), std::inserter( diff, diff.begin() ) ); |
---|
| 1018 | DTOR_PRINT( |
---|
| 1019 | std::cerr << "S_L-S_G = " << printSet( diff ) << std::endl; |
---|
| 1020 | ) |
---|
| 1021 | if ( ! diff.empty() ) { |
---|
[ca9d65e] | 1022 | SemanticError( stmt->location, "jump to label \"%s\" crosses initialization of \"%s\".", |
---|
| 1023 | stmt->target.name.c_str(), (*diff.begin())->name.c_str() ); |
---|
[17c13b9] | 1024 | } // if |
---|
| 1025 | } |
---|
[490fb92e] | 1026 | |
---|
[17c13b9] | 1027 | void InsertDtors::previsit( const ast::BranchStmt * stmt ) { |
---|
| 1028 | switch( stmt->kind ) { |
---|
| 1029 | case ast::BranchStmt::Continue: |
---|
| 1030 | case ast::BranchStmt::Break: |
---|
| 1031 | // could optimize the break/continue case, because the S_L-S_G check is unnecessary (this set should |
---|
| 1032 | // always be empty), but it serves as a small sanity check. |
---|
| 1033 | case ast::BranchStmt::Goto: |
---|
| 1034 | handleGoto( stmt ); |
---|
| 1035 | break; |
---|
| 1036 | default: |
---|
| 1037 | assert( false ); |
---|
| 1038 | } // switch |
---|
| 1039 | } |
---|
[490fb92e] | 1040 | |
---|
[a4ed165] | 1041 | /// Should we check for warnings? (The function is user-defined constrctor or destructor.) |
---|
[17c13b9] | 1042 | bool checkWarnings( const ast::FunctionDecl * funcDecl ) { |
---|
| 1043 | if ( ! funcDecl ) return false; |
---|
| 1044 | if ( ! funcDecl->stmts ) return false; |
---|
| 1045 | return CodeGen::isCtorDtor( funcDecl->name ) && ! funcDecl->linkage.is_overrideable; |
---|
| 1046 | } |
---|
[490fb92e] | 1047 | |
---|
[17c13b9] | 1048 | void GenStructMemberCalls::previsit( const ast::FunctionDecl * funcDecl ) { |
---|
| 1049 | GuardValue( function ); |
---|
| 1050 | GuardValue( unhandled ); |
---|
| 1051 | GuardValue( usedUninit ); |
---|
| 1052 | GuardValue( thisParam ); |
---|
| 1053 | GuardValue( isCtor ); |
---|
| 1054 | GuardValue( structDecl ); |
---|
| 1055 | errors = SemanticErrorException(); // clear previous errors |
---|
| 1056 | |
---|
| 1057 | // need to start with fresh sets |
---|
| 1058 | unhandled.clear(); |
---|
| 1059 | usedUninit.clear(); |
---|
| 1060 | |
---|
| 1061 | function = mutate(funcDecl); |
---|
| 1062 | // could this be non-unique? |
---|
| 1063 | if (function != funcDecl) { |
---|
| 1064 | std::cerr << "GenStructMemberCalls: non-unique FunctionDecl " << funcDecl->location << funcDecl->name << std::endl; |
---|
[0e707bd] | 1065 | } |
---|
[490fb92e] | 1066 | |
---|
[17c13b9] | 1067 | isCtor = CodeGen::isConstructor( function->name ); |
---|
[a4ed165] | 1068 | |
---|
| 1069 | // Remaining code is only for warnings. |
---|
| 1070 | if ( ! checkWarnings( function ) ) return; |
---|
| 1071 | thisParam = function->params.front().strict_as<ast::ObjectDecl>(); |
---|
| 1072 | auto thisType = getPointerBase( thisParam->get_type() ); |
---|
| 1073 | auto structType = dynamic_cast< const ast::StructInstType * >( thisType ); |
---|
| 1074 | if ( structType ) { |
---|
| 1075 | structDecl = structType->base; |
---|
| 1076 | for ( auto & member : structDecl->members ) { |
---|
| 1077 | if ( auto field = member.as<ast::ObjectDecl>() ) { |
---|
| 1078 | // record all of the struct type's members that need to be constructed or |
---|
| 1079 | // destructed by the end of the function |
---|
| 1080 | unhandled.insert( field ); |
---|
[17c13b9] | 1081 | } |
---|
| 1082 | } |
---|
[0e707bd] | 1083 | } |
---|
[17c13b9] | 1084 | } |
---|
[490fb92e] | 1085 | |
---|
[17c13b9] | 1086 | const ast::DeclWithType * GenStructMemberCalls::postvisit( const ast::FunctionDecl * funcDecl ) { |
---|
| 1087 | // remove the unhandled objects from usedUninit, because a call is inserted |
---|
| 1088 | // to handle them - only objects that are later constructed are used uninitialized. |
---|
| 1089 | std::map< const ast::DeclWithType *, CodeLocation > diff; |
---|
| 1090 | // need the comparator since usedUninit and unhandled have different types |
---|
| 1091 | struct comp_t { |
---|
| 1092 | typedef decltype(usedUninit)::value_type usedUninit_t; |
---|
| 1093 | typedef decltype(unhandled)::value_type unhandled_t; |
---|
| 1094 | bool operator()(usedUninit_t x, unhandled_t y) { return x.first < y; } |
---|
| 1095 | bool operator()(unhandled_t x, usedUninit_t y) { return x < y.first; } |
---|
| 1096 | } comp; |
---|
| 1097 | std::set_difference( usedUninit.begin(), usedUninit.end(), unhandled.begin(), unhandled.end(), std::inserter( diff, diff.begin() ), comp ); |
---|
| 1098 | for ( auto p : diff ) { |
---|
| 1099 | auto member = p.first; |
---|
| 1100 | auto loc = p.second; |
---|
| 1101 | // xxx - make error message better by also tracking the location that the object is constructed at? |
---|
| 1102 | emit( loc, "in ", function->name, ", field ", member->name, " used before being constructed" ); |
---|
| 1103 | } |
---|
[0e707bd] | 1104 | |
---|
[17c13b9] | 1105 | const CodeLocation loc = funcDecl->location; |
---|
[0e707bd] | 1106 | |
---|
[17c13b9] | 1107 | if ( ! unhandled.empty() ) { |
---|
| 1108 | auto mutStmts = function->stmts.get_and_mutate(); |
---|
| 1109 | // need to explicitly re-add function parameters to the indexer in order to resolve copy constructors |
---|
| 1110 | auto guard = makeFuncGuard( [this]() { symtab.enterScope(); }, [this]() { symtab.leaveScope(); } ); |
---|
| 1111 | symtab.addFunction( function ); |
---|
| 1112 | auto global = transUnit().global; |
---|
[490fb92e] | 1113 | |
---|
[17c13b9] | 1114 | // need to iterate through members in reverse in order for |
---|
| 1115 | // ctor/dtor statements to come out in the right order |
---|
| 1116 | for ( auto & member : reverseIterate( structDecl->members ) ) { |
---|
| 1117 | auto field = member.as<ast::ObjectDecl>(); |
---|
| 1118 | // skip non-DWT members |
---|
| 1119 | if ( ! field ) continue; |
---|
| 1120 | // skip non-constructable members |
---|
| 1121 | if ( ! tryConstruct( field ) ) continue; |
---|
| 1122 | // skip handled members |
---|
| 1123 | if ( ! unhandled.count( field ) ) continue; |
---|
| 1124 | |
---|
| 1125 | // insert and resolve default/copy constructor call for each field that's unhandled |
---|
| 1126 | ast::Expr * arg2 = nullptr; |
---|
| 1127 | if ( function->name == "?{}" && isCopyFunction( function ) ) { |
---|
| 1128 | // if copy ctor, need to pass second-param-of-this-function.field |
---|
| 1129 | assert( function->params.size() == 2 ); |
---|
| 1130 | arg2 = new ast::MemberExpr(funcDecl->location, field, new ast::VariableExpr(funcDecl->location, function->params.back() ) ); |
---|
| 1131 | } |
---|
[0bd3faf] | 1132 | InitExpander srcParam( arg2 ); |
---|
[17c13b9] | 1133 | // cast away reference type and construct field. |
---|
| 1134 | ast::Expr * thisExpr = new ast::CastExpr(funcDecl->location, new ast::VariableExpr(funcDecl->location, thisParam ), thisParam->get_type()->stripReferences()); |
---|
| 1135 | ast::Expr * memberDest = new ast::MemberExpr(funcDecl->location, field, thisExpr ); |
---|
[4e2f1b2] | 1136 | const ast::Stmt * callStmt = SymTab::genImplicitCall( srcParam, memberDest, loc, function->name, field, static_cast<SymTab::LoopDirection>(isCtor) ); |
---|
[17c13b9] | 1137 | |
---|
| 1138 | if ( callStmt ) { |
---|
| 1139 | try { |
---|
| 1140 | callStmt = callStmt->accept( *visitor ); |
---|
| 1141 | if ( isCtor ) { |
---|
| 1142 | mutStmts->push_front( callStmt ); |
---|
| 1143 | } else { // TODO: don't generate destructor function/object for intrinsic calls |
---|
| 1144 | |
---|
| 1145 | // Optimization: do not need to call intrinsic destructors on members |
---|
| 1146 | if ( isIntrinsicSingleArgCallStmt( callStmt ) ) continue; |
---|
| 1147 | |
---|
| 1148 | // __Destructor _dtor0 = { (void *)&b.a1, (void (*)(void *)_destroy_A }; |
---|
| 1149 | std::list< ast::ptr<ast::Stmt> > stmtsToAdd; |
---|
| 1150 | |
---|
| 1151 | static UniqueName memberDtorNamer = { "__memberDtor" }; |
---|
| 1152 | assertf( global.dtorStruct, "builtin __Destructor not found." ); |
---|
| 1153 | assertf( global.dtorDestroy, "builtin __destroy_Destructor not found." ); |
---|
| 1154 | |
---|
| 1155 | ast::Expr * thisExpr = new ast::CastExpr( new ast::AddressExpr( new ast::VariableExpr(loc, thisParam ) ), new ast::PointerType( new ast::VoidType(), ast::CV::Qualifiers() ) ); |
---|
| 1156 | ast::Expr * dtorExpr = new ast::VariableExpr(loc, getDtorFunc( thisParam, callStmt, stmtsToAdd ) ); |
---|
| 1157 | |
---|
| 1158 | // cast destructor pointer to void (*)(void *), to silence GCC incompatible pointer warnings |
---|
| 1159 | auto dtorFtype = new ast::FunctionType(); |
---|
| 1160 | dtorFtype->params.emplace_back( new ast::PointerType( new ast::VoidType() ) ); |
---|
| 1161 | auto dtorType = new ast::PointerType( dtorFtype ); |
---|
| 1162 | |
---|
| 1163 | auto destructor = new ast::ObjectDecl(loc, memberDtorNamer.newName(), new ast::StructInstType( global.dtorStruct ), new ast::ListInit(loc, { new ast::SingleInit(loc, thisExpr ), new ast::SingleInit(loc, new ast::CastExpr( dtorExpr, dtorType ) ) } ) ); |
---|
| 1164 | destructor->attributes.push_back( new ast::Attribute( "cleanup", { new ast::VariableExpr( loc, global.dtorDestroy ) } ) ); |
---|
| 1165 | mutStmts->push_front( new ast::DeclStmt(loc, destructor ) ); |
---|
| 1166 | mutStmts->kids.splice( mutStmts->kids.begin(), stmtsToAdd ); |
---|
[490fb92e] | 1167 | } |
---|
[17c13b9] | 1168 | } catch ( SemanticErrorException & error ) { |
---|
| 1169 | emit( funcDecl->location, "in ", function->name , ", field ", field->name, " not explicitly ", isCtor ? "constructed" : "destructed", " and no ", isCtor ? "default constructor" : "destructor", " found" ); |
---|
[490fb92e] | 1170 | } |
---|
| 1171 | } |
---|
| 1172 | } |
---|
[17c13b9] | 1173 | function->stmts = mutStmts; |
---|
[0e707bd] | 1174 | } |
---|
[17c13b9] | 1175 | if (! errors.isEmpty()) { |
---|
| 1176 | throw errors; |
---|
| 1177 | } |
---|
| 1178 | return function; |
---|
| 1179 | } |
---|
[490fb92e] | 1180 | |
---|
[17c13b9] | 1181 | /// true if expr is effectively just the 'this' parameter |
---|
| 1182 | bool isThisExpression( const ast::Expr * expr, const ast::DeclWithType * thisParam ) { |
---|
| 1183 | // TODO: there are more complicated ways to pass 'this' to a constructor, e.g. &*, *&, etc. |
---|
| 1184 | if ( auto varExpr = dynamic_cast< const ast::VariableExpr * >( expr ) ) { |
---|
| 1185 | return varExpr->var == thisParam; |
---|
| 1186 | } else if ( auto castExpr = dynamic_cast< const ast::CastExpr * > ( expr ) ) { |
---|
| 1187 | return isThisExpression( castExpr->arg, thisParam ); |
---|
| 1188 | } |
---|
| 1189 | return false; |
---|
| 1190 | } |
---|
[490fb92e] | 1191 | |
---|
[17c13b9] | 1192 | /// returns a MemberExpr if expr is effectively just member access on the 'this' parameter, else nullptr |
---|
| 1193 | const ast::MemberExpr * isThisMemberExpr( const ast::Expr * expr, const ast::DeclWithType * thisParam ) { |
---|
| 1194 | if ( auto memberExpr = dynamic_cast< const ast::MemberExpr * >( expr ) ) { |
---|
| 1195 | if ( isThisExpression( memberExpr->aggregate, thisParam ) ) { |
---|
| 1196 | return memberExpr; |
---|
[490fb92e] | 1197 | } |
---|
[17c13b9] | 1198 | } else if ( auto castExpr = dynamic_cast< const ast::CastExpr * >( expr ) ) { |
---|
| 1199 | return isThisMemberExpr( castExpr->arg, thisParam ); |
---|
[0e707bd] | 1200 | } |
---|
[17c13b9] | 1201 | return nullptr; |
---|
| 1202 | } |
---|
[490fb92e] | 1203 | |
---|
[17c13b9] | 1204 | void GenStructMemberCalls::previsit( const ast::ApplicationExpr * appExpr ) { |
---|
| 1205 | if ( ! checkWarnings( function ) ) { |
---|
| 1206 | visit_children = false; |
---|
| 1207 | return; |
---|
[0e707bd] | 1208 | } |
---|
[490fb92e] | 1209 | |
---|
[17c13b9] | 1210 | std::string fname = getFunctionName( appExpr ); |
---|
[a4ed165] | 1211 | if ( fname != function->name ) return; |
---|
| 1212 | |
---|
| 1213 | // call to same kind of function |
---|
| 1214 | const ast::Expr * firstParam = appExpr->args.front(); |
---|
| 1215 | if ( isThisExpression( firstParam, thisParam ) ) { |
---|
| 1216 | // if calling another constructor on thisParam, assume that function handles |
---|
| 1217 | // all members - if it doesn't a warning will appear in that function. |
---|
| 1218 | unhandled.clear(); |
---|
| 1219 | } else if ( auto memberExpr = isThisMemberExpr( firstParam, thisParam ) ) { |
---|
| 1220 | // if first parameter is a member expression on the this parameter, |
---|
| 1221 | // then remove the member from unhandled set. |
---|
| 1222 | if ( isThisExpression( memberExpr->aggregate, thisParam ) ) { |
---|
| 1223 | unhandled.erase( memberExpr->member ); |
---|
[490fb92e] | 1224 | } |
---|
[0e707bd] | 1225 | } |
---|
[17c13b9] | 1226 | } |
---|
[490fb92e] | 1227 | |
---|
[17c13b9] | 1228 | void GenStructMemberCalls::previsit( const ast::MemberExpr * memberExpr ) { |
---|
| 1229 | if ( ! checkWarnings( function ) || ! isCtor ) { |
---|
| 1230 | visit_children = false; |
---|
| 1231 | return; |
---|
| 1232 | } |
---|
[490fb92e] | 1233 | |
---|
[17c13b9] | 1234 | if ( isThisExpression( memberExpr->aggregate, thisParam ) ) { |
---|
| 1235 | if ( unhandled.count( memberExpr->member ) ) { |
---|
| 1236 | // emit a warning because a member was used before it was constructed |
---|
| 1237 | usedUninit.insert( { memberExpr->member, memberExpr->location } ); |
---|
[490fb92e] | 1238 | } |
---|
[0e707bd] | 1239 | } |
---|
[17c13b9] | 1240 | } |
---|
[490fb92e] | 1241 | |
---|
[17c13b9] | 1242 | template< typename... Params > |
---|
| 1243 | void GenStructMemberCalls::emit( CodeLocation loc, const Params &... params ) { |
---|
| 1244 | SemanticErrorException err( loc, toString( params... ) ); |
---|
| 1245 | errors.append( err ); |
---|
| 1246 | } |
---|
[490fb92e] | 1247 | |
---|
[17c13b9] | 1248 | const ast::Expr * GenStructMemberCalls::postvisit( const ast::UntypedExpr * untypedExpr ) { |
---|
| 1249 | // xxx - functions returning ast::ptr seems wrong... |
---|
| 1250 | auto res = ResolvExpr::findVoidExpression( untypedExpr, { symtab, transUnit().global } ); |
---|
| 1251 | return res.release(); |
---|
| 1252 | } |
---|
[490fb92e] | 1253 | |
---|
[17c13b9] | 1254 | void InsertImplicitCalls::previsit(const ast::UniqueExpr * unqExpr) { |
---|
| 1255 | if (visitedIds.count(unqExpr->id)) visit_children = false; |
---|
| 1256 | else visitedIds.insert(unqExpr->id); |
---|
| 1257 | } |
---|
[490fb92e] | 1258 | |
---|
[17c13b9] | 1259 | const ast::Expr * FixCtorExprs::postvisit( const ast::ConstructorExpr * ctorExpr ) { |
---|
| 1260 | const CodeLocation loc = ctorExpr->location; |
---|
| 1261 | static UniqueName tempNamer( "_tmp_ctor_expr" ); |
---|
| 1262 | // xxx - is the size check necessary? |
---|
| 1263 | assert( ctorExpr->result && ctorExpr->result->size() == 1 ); |
---|
| 1264 | |
---|
| 1265 | // xxx - this can be TupleAssignExpr now. Need to properly handle this case. |
---|
| 1266 | // take possession of expr and env |
---|
| 1267 | ast::ptr<ast::ApplicationExpr> callExpr = ctorExpr->callExpr.strict_as<ast::ApplicationExpr>(); |
---|
| 1268 | ast::ptr<ast::TypeSubstitution> env = ctorExpr->env; |
---|
| 1269 | |
---|
| 1270 | // xxx - ideally we would reuse the temporary generated from the copy constructor passes from within firstArg if it exists and not generate a temporary if it's unnecessary. |
---|
| 1271 | auto tmp = new ast::ObjectDecl(loc, tempNamer.newName(), callExpr->args.front()->result ); |
---|
| 1272 | declsToAddBefore.push_back( tmp ); |
---|
| 1273 | |
---|
| 1274 | // build assignment and replace constructor's first argument with new temporary |
---|
| 1275 | auto mutCallExpr = callExpr.get_and_mutate(); |
---|
| 1276 | const ast::Expr * firstArg = callExpr->args.front(); |
---|
| 1277 | ast::Expr * assign = new ast::UntypedExpr(loc, new ast::NameExpr(loc, "?=?" ), { new ast::AddressExpr(loc, new ast::VariableExpr(loc, tmp ) ), new ast::AddressExpr( firstArg ) } ); |
---|
| 1278 | firstArg = new ast::VariableExpr(loc, tmp ); |
---|
| 1279 | mutCallExpr->args.front() = firstArg; |
---|
| 1280 | |
---|
| 1281 | // resolve assignment and dispose of new env |
---|
| 1282 | auto resolved = ResolvExpr::findVoidExpression( assign, { symtab, transUnit().global } ); |
---|
| 1283 | auto mut = resolved.get_and_mutate(); |
---|
| 1284 | assertf(resolved.get() == mut, "newly resolved expression must be unique"); |
---|
| 1285 | mut->env = nullptr; |
---|
| 1286 | |
---|
| 1287 | // for constructor expr: |
---|
| 1288 | // T x; |
---|
| 1289 | // x{}; |
---|
| 1290 | // results in: |
---|
| 1291 | // T x; |
---|
| 1292 | // T & tmp; |
---|
| 1293 | // &tmp = &x, ?{}(tmp), tmp |
---|
| 1294 | ast::CommaExpr * commaExpr = new ast::CommaExpr(loc, resolved, new ast::CommaExpr(loc, mutCallExpr, new ast::VariableExpr(loc, tmp ) ) ); |
---|
| 1295 | commaExpr->env = env; |
---|
| 1296 | return commaExpr; |
---|
| 1297 | } |
---|
[490fb92e] | 1298 | |
---|
[17c13b9] | 1299 | } // namespace |
---|
[0e707bd] | 1300 | |
---|
[17c13b9] | 1301 | void fix( ast::TranslationUnit & translationUnit, bool inLibrary ) { |
---|
| 1302 | ast::Pass<SelfAssignChecker>::run( translationUnit ); |
---|
| 1303 | |
---|
| 1304 | // fixes StmtExpr to properly link to their resulting expression |
---|
| 1305 | ast::Pass<StmtExprResult>::run( translationUnit ); |
---|
| 1306 | |
---|
| 1307 | // fixes ConstructorInit for global variables. should happen before fixInitializers. |
---|
| 1308 | InitTweak::fixGlobalInit( translationUnit, inLibrary ); |
---|
| 1309 | |
---|
| 1310 | // must happen before ResolveCopyCtors because temporaries have to be inserted into the correct scope |
---|
| 1311 | ast::Pass<SplitExpressions>::run( translationUnit ); |
---|
| 1312 | |
---|
| 1313 | ast::Pass<InsertImplicitCalls>::run( translationUnit ); |
---|
[0e707bd] | 1314 | |
---|
[17c13b9] | 1315 | // Needs to happen before ResolveCopyCtors, because argument/return temporaries should not be considered in |
---|
| 1316 | // error checking branch statements |
---|
| 1317 | { |
---|
| 1318 | ast::Pass<LabelFinder> finder; |
---|
| 1319 | ast::Pass<InsertDtors>::run( translationUnit, finder ); |
---|
[0e707bd] | 1320 | } |
---|
[17c13b9] | 1321 | |
---|
| 1322 | ast::Pass<ResolveCopyCtors>::run( translationUnit ); |
---|
| 1323 | FixInit::fixInitializers( translationUnit ); |
---|
| 1324 | ast::Pass<GenStructMemberCalls>::run( translationUnit ); |
---|
| 1325 | |
---|
| 1326 | // Needs to happen after GenStructMemberCalls, since otherwise member constructors exprs |
---|
| 1327 | // don't have the correct form, and a member can be constructed more than once. |
---|
| 1328 | ast::Pass<FixCtorExprs>::run( translationUnit ); |
---|
| 1329 | } |
---|
| 1330 | |
---|
[490fb92e] | 1331 | } // namespace InitTweak |
---|
| 1332 | |
---|
| 1333 | // Local Variables: // |
---|
| 1334 | // tab-width: 4 // |
---|
| 1335 | // mode: c++ // |
---|
| 1336 | // compile-command: "make install" // |
---|
| 1337 | // End: // |
---|