Author: arphaman Date: Thu Apr 6 07:53:43 2017 New Revision: 299646 URL: http://llvm.org/viewvc/llvm-project?rev=299646&view=rev Log: Fix lambda to block conversion in C++17 by avoiding copy elision for the lambda capture used by the created block
The commit r288866 introduced guaranteed copy elision to C++ 17. This unfortunately broke the lambda to block conversion in C++17 (the compiler crashes when performing IRGen). This commit fixes the conversion by avoiding copy elision for the capture that captures the lambda that's used in the block created by the lambda to block conversion process. rdar://31385153 Differential Revision: https://reviews.llvm.org/D31669 Added: cfe/trunk/test/CodeGenObjCXX/lambda-to-block.mm Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td cfe/trunk/include/clang/Sema/Initialization.h cfe/trunk/lib/Sema/SemaInit.cpp cfe/trunk/lib/Sema/SemaLambda.cpp Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=299646&r1=299645&r2=299646&view=diff ============================================================================== --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original) +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Thu Apr 6 07:53:43 2017 @@ -1689,8 +1689,8 @@ def err_init_conversion_failed : Error< "cannot initialize %select{a variable|a parameter|return object|an " "exception object|a member subobject|an array element|a new value|a value|a " "base class|a constructor delegation|a vector element|a block element|a " - "complex element|a lambda capture|a compound literal initializer|a " - "related result|a parameter of CF audited function}0 " + "block element|a complex element|a lambda capture|a compound literal " + "initializer|a related result|a parameter of CF audited function}0 " "%diff{of type $ with an %select{rvalue|lvalue}2 of type $|" "with an %select{rvalue|lvalue}2 of incompatible type}1,3" "%select{|: different classes%diff{ ($ vs $)|}5,6" Modified: cfe/trunk/include/clang/Sema/Initialization.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Initialization.h?rev=299646&r1=299645&r2=299646&view=diff ============================================================================== --- cfe/trunk/include/clang/Sema/Initialization.h (original) +++ cfe/trunk/include/clang/Sema/Initialization.h Thu Apr 6 07:53:43 2017 @@ -70,6 +70,9 @@ public: /// \brief The entity being initialized is a field of block descriptor for /// the copied-in c++ object. EK_BlockElement, + /// The entity being initialized is a field of block descriptor for the + /// copied-in lambda object that's used in the lambda to block conversion. + EK_LambdaToBlockConversionBlockElement, /// \brief The entity being initialized is the real or imaginary part of a /// complex number. EK_ComplexElement, @@ -260,7 +263,13 @@ public: QualType Type, bool NRVO) { return InitializedEntity(EK_BlockElement, BlockVarLoc, Type, NRVO); } - + + static InitializedEntity InitializeLambdaToBlock(SourceLocation BlockVarLoc, + QualType Type, bool NRVO) { + return InitializedEntity(EK_LambdaToBlockConversionBlockElement, + BlockVarLoc, Type, NRVO); + } + /// \brief Create the initialization entity for an exception object. static InitializedEntity InitializeException(SourceLocation ThrowLoc, QualType Type, bool NRVO) { Modified: cfe/trunk/lib/Sema/SemaInit.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaInit.cpp?rev=299646&r1=299645&r2=299646&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaInit.cpp (original) +++ cfe/trunk/lib/Sema/SemaInit.cpp Thu Apr 6 07:53:43 2017 @@ -950,6 +950,7 @@ static void warnBracedScalarInit(Sema &S case InitializedEntity::EK_Base: case InitializedEntity::EK_Delegating: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_Binding: llvm_unreachable("unexpected braced scalar init"); } @@ -2934,6 +2935,7 @@ DeclarationName InitializedEntity::getNa case EK_VectorElement: case EK_ComplexElement: case EK_BlockElement: + case EK_LambdaToBlockConversionBlockElement: case EK_CompoundLiteralInit: case EK_RelatedResult: return DeclarationName(); @@ -2963,6 +2965,7 @@ ValueDecl *InitializedEntity::getDecl() case EK_VectorElement: case EK_ComplexElement: case EK_BlockElement: + case EK_LambdaToBlockConversionBlockElement: case EK_LambdaCapture: case EK_CompoundLiteralInit: case EK_RelatedResult: @@ -2992,6 +2995,7 @@ bool InitializedEntity::allowsNRVO() con case EK_VectorElement: case EK_ComplexElement: case EK_BlockElement: + case EK_LambdaToBlockConversionBlockElement: case EK_LambdaCapture: case EK_RelatedResult: break; @@ -3025,6 +3029,9 @@ unsigned InitializedEntity::dumpImpl(raw case EK_VectorElement: OS << "VectorElement " << Index; break; case EK_ComplexElement: OS << "ComplexElement " << Index; break; case EK_BlockElement: OS << "Block"; break; + case EK_LambdaToBlockConversionBlockElement: + OS << "Block (lambda)"; + break; case EK_LambdaCapture: OS << "LambdaCapture "; OS << DeclarationName(Capture.VarID); @@ -3622,9 +3629,13 @@ static void TryConstructorInitialization // destination object. // Per DR (no number yet), this does not apply when initializing a base // class or delegating to another constructor from a mem-initializer. + // ObjC++: Lambda captured by the block in the lambda to block conversion + // should avoid copy elision. if (S.getLangOpts().CPlusPlus1z && Entity.getKind() != InitializedEntity::EK_Base && Entity.getKind() != InitializedEntity::EK_Delegating && + Entity.getKind() != + InitializedEntity::EK_LambdaToBlockConversionBlockElement && UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isRValue() && S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) { // Convert qualifications if necessary. @@ -5488,6 +5499,7 @@ getAssignmentAction(const InitializedEnt case InitializedEntity::EK_VectorElement: case InitializedEntity::EK_ComplexElement: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_LambdaCapture: case InitializedEntity::EK_CompoundLiteralInit: return Sema::AA_Initializing; @@ -5511,6 +5523,7 @@ static bool shouldBindAsTemporary(const case InitializedEntity::EK_ComplexElement: case InitializedEntity::EK_Exception: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_LambdaCapture: case InitializedEntity::EK_CompoundLiteralInit: return false; @@ -5537,6 +5550,7 @@ static bool shouldDestroyEntity(const In case InitializedEntity::EK_VectorElement: case InitializedEntity::EK_ComplexElement: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_LambdaCapture: return false; @@ -5584,6 +5598,7 @@ static SourceLocation getInitializationL case InitializedEntity::EK_VectorElement: case InitializedEntity::EK_ComplexElement: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_CompoundLiteralInit: case InitializedEntity::EK_RelatedResult: return Initializer->getLocStart(); @@ -6021,6 +6036,7 @@ InitializedEntityOutlivesFullExpression( case InitializedEntity::EK_ArrayElement: case InitializedEntity::EK_VectorElement: case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_ComplexElement: // Could not determine what the full initialization is. Assume it might not // outlive the full-expression. @@ -6109,6 +6125,7 @@ static const InitializedEntity *getEntit return FallbackDecl; case InitializedEntity::EK_BlockElement: + case InitializedEntity::EK_LambdaToBlockConversionBlockElement: case InitializedEntity::EK_LambdaCapture: case InitializedEntity::EK_Exception: case InitializedEntity::EK_VectorElement: Modified: cfe/trunk/lib/Sema/SemaLambda.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaLambda.cpp?rev=299646&r1=299645&r2=299646&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaLambda.cpp (original) +++ cfe/trunk/lib/Sema/SemaLambda.cpp Thu Apr 6 07:53:43 2017 @@ -1649,10 +1649,9 @@ ExprResult Sema::BuildBlockForLambdaConv CallOperator->markUsed(Context); ExprResult Init = PerformCopyInitialization( - InitializedEntity::InitializeBlock(ConvLocation, - Src->getType(), - /*NRVO=*/false), - CurrentLocation, Src); + InitializedEntity::InitializeLambdaToBlock(ConvLocation, Src->getType(), + /*NRVO=*/false), + CurrentLocation, Src); if (!Init.isInvalid()) Init = ActOnFinishFullExpr(Init.get()); Added: cfe/trunk/test/CodeGenObjCXX/lambda-to-block.mm URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjCXX/lambda-to-block.mm?rev=299646&view=auto ============================================================================== --- cfe/trunk/test/CodeGenObjCXX/lambda-to-block.mm (added) +++ cfe/trunk/test/CodeGenObjCXX/lambda-to-block.mm Thu Apr 6 07:53:43 2017 @@ -0,0 +1,18 @@ +// RUN: %clang_cc1 -x objective-c++ -fblocks -triple x86_64-apple-darwin10 -fobjc-runtime=macosx-fragile-10.5 -std=c++1z -emit-llvm -o - %s | FileCheck %s + +// rdar://31385153 +// Shouldn't crash! + +void takesBlock(void (^)(void)); + +struct Copyable { + Copyable(const Copyable &x); +}; + +void hasLambda(Copyable x) { + takesBlock([x] () { }); +} +// CHECK-LABEL: define internal void @__copy_helper_block_ +// CHECK: call void @"_ZZ9hasLambda8CopyableEN3$_0C1ERKS0_" +// CHECK-LABEL: define internal void @"_ZZ9hasLambda8CopyableEN3$_0C2ERKS0_" +// CHECK: call void @_ZN8CopyableC1ERKS_ _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits