Author: yronglin Date: 2024-04-15T23:52:26+08:00 New Revision: 7b9b28dbd2938877a94737e28b7eb9e3cdd82755
URL: https://github.com/llvm/llvm-project/commit/7b9b28dbd2938877a94737e28b7eb9e3cdd82755 DIFF: https://github.com/llvm/llvm-project/commit/7b9b28dbd2938877a94737e28b7eb9e3cdd82755.diff LOG: [Clang] Refactor implementation of "Lifetime extension in range-based for loops" (#87930) This PR remove `InMaterializeTemporaryObjectContext` , because it's redundant, materialize non-cv void prvalue temporaries in discarded expressions can only appear under lifetime-extension context. Signed-off-by: yronglin <yronglin...@gmail.com> Added: Modified: clang/include/clang/Sema/Sema.h clang/lib/Parse/ParseDecl.cpp clang/lib/Sema/SemaExpr.cpp clang/lib/Sema/SemaExprCXX.cpp clang/lib/Sema/SemaTemplateInstantiateDecl.cpp clang/lib/Sema/TreeTransform.h Removed: ################################################################################ diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h index c6035445e90192..d93ac7863b721d 100644 --- a/clang/include/clang/Sema/Sema.h +++ b/clang/include/clang/Sema/Sema.h @@ -5099,34 +5099,6 @@ class Sema final : public SemaBase { /// example, in a for-range initializer). bool InLifetimeExtendingContext = false; - /// Whether we are currently in a context in which all temporaries must be - /// materialized. - /// - /// [class.temporary]/p2: - /// The materialization of a temporary object is generally delayed as long - /// as possible in order to avoid creating unnecessary temporary objects. - /// - /// Temporary objects are materialized: - /// (2.1) when binding a reference to a prvalue ([dcl.init.ref], - /// [expr.type.conv], [expr.dynamic.cast], [expr.static.cast], - /// [expr.const.cast], [expr.cast]), - /// - /// (2.2) when performing member access on a class prvalue ([expr.ref], - /// [expr.mptr.oper]), - /// - /// (2.3) when performing an array-to-pointer conversion or subscripting - /// on an array prvalue ([conv.array], [expr.sub]), - /// - /// (2.4) when initializing an object of type - /// std::initializer_list<T> from a braced-init-list - /// ([dcl.init.list]), - /// - /// (2.5) for certain unevaluated operands ([expr.typeid], [expr.sizeof]) - /// - /// (2.6) when a prvalue that has type other than cv void appears as a - /// discarded-value expression ([expr.context]). - bool InMaterializeTemporaryObjectContext = false; - // When evaluating immediate functions in the initializer of a default // argument or default member initializer, this is the declaration whose // default initializer is being evaluated and the location of the call @@ -6398,19 +6370,6 @@ class Sema final : public SemaBase { } } - /// keepInMaterializeTemporaryObjectContext - Pull down - /// InMaterializeTemporaryObjectContext flag from previous context. - void keepInMaterializeTemporaryObjectContext() { - if (ExprEvalContexts.size() > 2 && - ExprEvalContexts[ExprEvalContexts.size() - 2] - .InMaterializeTemporaryObjectContext) { - auto &LastRecord = ExprEvalContexts.back(); - auto &PrevRecord = ExprEvalContexts[ExprEvalContexts.size() - 2]; - LastRecord.InMaterializeTemporaryObjectContext = - PrevRecord.InMaterializeTemporaryObjectContext; - } - } - DefaultedComparisonKind getDefaultedComparisonKind(const FunctionDecl *FD) { return getDefaultedFunctionKind(FD).asComparison(); } @@ -6554,12 +6513,6 @@ class Sema final : public SemaBase { /// used in initializer of the field. llvm::MapVector<FieldDecl *, DeleteLocs> DeleteExprs; - bool isInMaterializeTemporaryObjectContext() const { - assert(!ExprEvalContexts.empty() && - "Must be in an expression evaluation context"); - return ExprEvalContexts.back().InMaterializeTemporaryObjectContext; - } - ParsedType getInheritingConstructorName(CXXScopeSpec &SS, SourceLocation NameLoc, const IdentifierInfo &Name); diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index a990ef398c8230..2b934234b7cf5d 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -2380,10 +2380,6 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS, if (getLangOpts().CPlusPlus23) { auto &LastRecord = Actions.ExprEvalContexts.back(); LastRecord.InLifetimeExtendingContext = true; - - // Materialize non-`cv void` prvalue temporaries in discarded - // expressions. These materialized temporaries may be lifetime-extented. - LastRecord.InMaterializeTemporaryObjectContext = true; } if (getLangOpts().OpenMP) diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index c5395fb2068a18..24f354f1c72498 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -6314,7 +6314,6 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc, // Pass down lifetime extending flag, and collect temporaries in // CreateMaterializeTemporaryExpr when we rewrite the call argument. keepInLifetimeExtendingContext(); - keepInMaterializeTemporaryObjectContext(); EnsureImmediateInvocationInDefaultArgs Immediate(*this); ExprResult Res; runWithSufficientStackSpace(CallLoc, [&] { @@ -18679,9 +18678,9 @@ void Sema::PopExpressionEvaluationContext() { // Append the collected materialized temporaries into previous context before // exit if the previous also is a lifetime extending context. auto &PrevRecord = ExprEvalContexts[ExprEvalContexts.size() - 2]; - if (getLangOpts().CPlusPlus23 && isInLifetimeExtendingContext() && - PrevRecord.InLifetimeExtendingContext && !ExprEvalContexts.empty()) { - auto &PrevRecord = ExprEvalContexts[ExprEvalContexts.size() - 2]; + if (getLangOpts().CPlusPlus23 && Rec.InLifetimeExtendingContext && + PrevRecord.InLifetimeExtendingContext && + !Rec.ForRangeLifetimeExtendTemps.empty()) { PrevRecord.ForRangeLifetimeExtendTemps.append( Rec.ForRangeLifetimeExtendTemps); } diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index fa7b92a43346b1..74ed3fe7bd5201 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -8429,7 +8429,7 @@ ExprResult Sema::IgnoredValueConversions(Expr *E) { // unnecessary temporary objects. If we skip this step, IR generation is // able to synthesize the storage for itself in the aggregate case, and // adding the extra node to the AST is just clutter. - if (isInMaterializeTemporaryObjectContext() && getLangOpts().CPlusPlus17 && + if (isInLifetimeExtendingContext() && getLangOpts().CPlusPlus17 && E->isPRValue() && !E->getType()->isVoidType()) { ExprResult Res = TemporaryMaterializationConversion(E); if (Res.isInvalid()) diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp index 02d0b35ce940f1..c45a8d1408fff3 100644 --- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp +++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp @@ -5483,7 +5483,6 @@ void Sema::InstantiateVariableInitializer( *this, Sema::ExpressionEvaluationContext::PotentiallyEvaluated, Var); keepInLifetimeExtendingContext(); - keepInMaterializeTemporaryObjectContext(); // Instantiate the initializer. ExprResult Init; diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h index fdf84c512c4931..8c96134af7c8f0 100644 --- a/clang/lib/Sema/TreeTransform.h +++ b/clang/lib/Sema/TreeTransform.h @@ -4177,7 +4177,6 @@ ExprResult TreeTransform<Derived>::TransformInitializer(Expr *Init, getSema(), EnterExpressionEvaluationContext::InitList, Construct->isListInitialization()); - getSema().keepInLifetimeExtendingContext(); getSema().keepInLifetimeExtendingContext(); SmallVector<Expr*, 8> NewArgs; bool ArgChanged = false; @@ -8752,10 +8751,6 @@ TreeTransform<Derived>::TransformCXXForRangeStmt(CXXForRangeStmt *S) { if (getSema().getLangOpts().CPlusPlus23) { auto &LastRecord = getSema().ExprEvalContexts.back(); LastRecord.InLifetimeExtendingContext = true; - - // Materialize non-`cv void` prvalue temporaries in discarded - // expressions. These materialized temporaries may be lifetime-extented. - LastRecord.InMaterializeTemporaryObjectContext = true; } StmtResult Init = S->getInit() ? getDerived().TransformStmt(S->getInit()) : StmtResult(); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
