[C11] Implement WG14 N1285 (temporary lifetimes) (#133472)
This feature largely models the same behavior as in C++11. It is technically a breaking change between C99 and C11, so the paper is not being backported to older language modes. One difference between C++ and C is that things which are rvalues in C are often lvalues in C++ (such as the result of a ternary operator or a comma operator). Fixes #96486
This commit is contained in:
Aaron Ballman
GitHub
parent
71f629fc2a
commit
5c8ba28c75
@ -162,6 +162,18 @@ C23 Feature Support
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- Fixed a bug where you could not cast a null pointer constant to type
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``nullptr_t``. Fixes #GH133644.
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C11 Feature Support
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^^^^^^^^^^^^^^^^^^^
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- Implemented `WG14 N1285 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1285.htm>`_
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which introduces the notion of objects with a temporary lifetime. When an
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expression resulting in an rvalue with structure or union type and that type
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contains a member of array type, the expression result is an automatic storage
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duration object with temporary lifetime which begins when the expression is
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evaluated and ends at the evaluation of the containing full expression. This
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functionality is also implemented for earlier C language modes because the
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C99 semantics will never be implemented (it would require dynamic allocations
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of memory which leaks, which users would not appreciate).
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Non-comprehensive list of changes in this release
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-------------------------------------------------
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@ -2265,11 +2265,18 @@ void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
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cleanupKind & EHCleanup);
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}
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void CodeGenFunction::pushLifetimeExtendedDestroy(
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QualType::DestructionKind dtorKind, Address addr, QualType type) {
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CleanupKind cleanupKind = getCleanupKind(dtorKind);
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pushLifetimeExtendedDestroy(cleanupKind, addr, type, getDestroyer(dtorKind),
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cleanupKind & EHCleanup);
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}
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void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, Address addr,
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QualType type, Destroyer *destroyer,
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bool useEHCleanupForArray) {
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pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type,
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destroyer, useEHCleanupForArray);
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pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type, destroyer,
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useEHCleanupForArray);
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}
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// Pushes a destroy and defers its deactivation until its
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@ -393,55 +393,49 @@ pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
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}
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}
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CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
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if (const RecordType *RT =
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E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
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// Get the destructor for the reference temporary.
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auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
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if (!ClassDecl->hasTrivialDestructor())
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ReferenceTemporaryDtor = ClassDecl->getDestructor();
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}
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QualType::DestructionKind DK = E->getType().isDestructedType();
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if (DK != QualType::DK_none) {
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switch (M->getStorageDuration()) {
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case SD_Static:
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case SD_Thread: {
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CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
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if (const RecordType *RT =
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E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
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// Get the destructor for the reference temporary.
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if (auto *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl());
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ClassDecl && !ClassDecl->hasTrivialDestructor())
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ReferenceTemporaryDtor = ClassDecl->getDestructor();
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}
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if (!ReferenceTemporaryDtor)
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return;
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if (!ReferenceTemporaryDtor)
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return;
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// Call the destructor for the temporary.
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switch (M->getStorageDuration()) {
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case SD_Static:
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case SD_Thread: {
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llvm::FunctionCallee CleanupFn;
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llvm::Constant *CleanupArg;
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if (E->getType()->isArrayType()) {
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CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
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ReferenceTemporary, E->getType(),
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CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
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dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
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CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
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} else {
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CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor(
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GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete));
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CleanupArg = cast<llvm::Constant>(ReferenceTemporary.emitRawPointer(CGF));
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llvm::FunctionCallee CleanupFn;
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llvm::Constant *CleanupArg;
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if (E->getType()->isArrayType()) {
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CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
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ReferenceTemporary, E->getType(), CodeGenFunction::destroyCXXObject,
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CGF.getLangOpts().Exceptions,
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dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
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CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
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} else {
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CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor(
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GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete));
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CleanupArg =
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cast<llvm::Constant>(ReferenceTemporary.emitRawPointer(CGF));
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}
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CGF.CGM.getCXXABI().registerGlobalDtor(
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CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
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} break;
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case SD_FullExpression:
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CGF.pushDestroy(DK, ReferenceTemporary, E->getType());
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break;
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case SD_Automatic:
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CGF.pushLifetimeExtendedDestroy(DK, ReferenceTemporary, E->getType());
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break;
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case SD_Dynamic:
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llvm_unreachable("temporary cannot have dynamic storage duration");
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}
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CGF.CGM.getCXXABI().registerGlobalDtor(
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CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
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break;
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}
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case SD_FullExpression:
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CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
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CodeGenFunction::destroyCXXObject,
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CGF.getLangOpts().Exceptions);
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break;
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case SD_Automatic:
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CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
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ReferenceTemporary, E->getType(),
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CodeGenFunction::destroyCXXObject,
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CGF.getLangOpts().Exceptions);
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break;
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case SD_Dynamic:
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llvm_unreachable("temporary cannot have dynamic storage duration");
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}
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}
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@ -2249,6 +2249,8 @@ public:
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void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
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QualType type, Destroyer *destroyer,
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bool useEHCleanupForArray);
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void pushLifetimeExtendedDestroy(QualType::DestructionKind dtorKind,
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Address addr, QualType type);
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void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
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llvm::Value *CompletePtr,
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QualType ElementType);
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@ -7650,11 +7650,14 @@ Sema::CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary,
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}
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ExprResult Sema::TemporaryMaterializationConversion(Expr *E) {
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// In C++98, we don't want to implicitly create an xvalue.
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// In C++98, we don't want to implicitly create an xvalue. C11 added the
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// same rule, but C99 is broken without this behavior and so we treat the
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// change as applying to all C language modes.
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// FIXME: This means that AST consumers need to deal with "prvalues" that
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// denote materialized temporaries. Maybe we should add another ValueKind
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// for "xvalue pretending to be a prvalue" for C++98 support.
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if (!E->isPRValue() || !getLangOpts().CPlusPlus11)
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if (!E->isPRValue() ||
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(!getLangOpts().CPlusPlus11 && getLangOpts().CPlusPlus))
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return E;
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// C++1z [conv.rval]/1: T shall be a complete type.
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@ -1,24 +1,82 @@
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// RUN: %clang_cc1 -verify=wrong -std=c99 %s
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// RUN: %clang_cc1 -verify=wrong -std=c11 %s
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// RUN: %clang_cc1 -verify=cpp -std=c++11 -x c++ %s
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// RUN: %clang_cc1 -fsyntax-only -verify=expected,c -std=c99 %s
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// RUN: %clang_cc1 -fsyntax-only -verify=expected,c -std=c11 %s
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// RUN: %clang_cc1 -fsyntax-only -verify=expected,cpp -std=c++11 -x c++ %s
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/* WG14 N1285: No
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/* WG14 N1285: Clang 21
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* Extending the lifetime of temporary objects (factored approach)
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*
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* NB: we do not properly materialize temporary expressions in situations where
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* it would be expected; that is why the "no-diagnostics" marking is named
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* "wrong". We do issue the expected diagnostic in C++ mode.
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* This paper introduced the notion of an object with a temporary lifetime. Any
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* operation resulting in an rvalue of structure or union type which contains
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* an array results in an object with temporary lifetime.
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*
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* Even though this is a change for C11, we treat it as a DR and apply it
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* retroactively to earlier C language modes.
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*/
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// wrong-no-diagnostics
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// C11 6.2.4p8: A non-lvalue expression with structure or union type, where the
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// structure or union contains a member with array type (including,
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// recursively, members of all contained structures and unions) refers to an
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// object with automatic storage duration and temporary lifetime. Its lifetime
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// begins when the expression is evaluated and its initial value is the value
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// of the expression. Its lifetime ends when the evaluation of the containing
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// full expression or full declarator ends. Any attempt to modify an object
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// with temporary lifetime results in undefined behavior.
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struct X { int a[5]; };
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struct X f(void);
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int foo(void) {
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// FIXME: This diagnostic should be issued in C11 as well (though not in C99,
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// as this paper was a breaking change between C99 and C11).
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int *p = f().a; // cpp-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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return *p;
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union U { int a[10]; double d; };
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union U g(void);
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void sink(int *);
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int func_return(void) {
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int *p = f().a; // expected-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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p = f().a; // expected-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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p = g().a; // expected-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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sink(f().a); // Ok
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return *f().a; // Ok
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}
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int ternary(void) {
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int *p = (1 ? (struct X){ 0 } : f()).a; // expected-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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int *r = (1 ? (union U){ 0 } : g()).a; // expected-warning {{temporary whose address is used as value of local variable 'r' will be destroyed at the end of the full-expression}}
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p = (1 ? (struct X){ 0 } : f()).a; // expected-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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sink((1 ? (struct X){ 0 } : f()).a); // Ok
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// This intentionally gets one diagnostic in C and two in C++. In C, the
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// compound literal results in an lvalue, not an rvalue as it does in C++. So
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// only one branch results in a temporary in C but both branches do in C++.
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int *q = 1 ? (struct X){ 0 }.a : f().a; // expected-warning {{temporary whose address is used as value of local variable 'q' will be destroyed at the end of the full-expression}} \
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cpp-warning {{temporary whose address is used as value of local variable 'q' will be destroyed at the end of the full-expression}}
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q = 1 ? (struct X){ 0 }.a : f().a; // expected-warning {{object backing the pointer q will be destroyed at the end of the full-expression}} \
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cpp-warning {{object backing the pointer q will be destroyed at the end of the full-expression}}
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q = 1 ? (struct X){ 0 }.a : g().a; // expected-warning {{object backing the pointer q will be destroyed at the end of the full-expression}} \
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cpp-warning {{object backing the pointer q will be destroyed at the end of the full-expression}}
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sink(1 ? (struct X){ 0 }.a : f().a); // Ok
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return *(1 ? (struct X){ 0 }.a : f().a); // Ok
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}
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int comma(void) {
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struct X x;
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int *p = ((void)0, x).a; // c-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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p = ((void)0, x).a; // c-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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sink(((void)0, x).a); // Ok
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return *(((void)0, x).a);// Ok
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}
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int cast(void) {
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struct X x;
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int *p = ((struct X)x).a; // expected-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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p = ((struct X)x).a; // expected-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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sink(((struct X)x).a); // Ok
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return *(((struct X)x).a); // Ok
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}
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int assign(void) {
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struct X x, s;
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int *p = (x = s).a; // c-warning {{temporary whose address is used as value of local variable 'p' will be destroyed at the end of the full-expression}}
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p = (x = s).a; // c-warning {{object backing the pointer p will be destroyed at the end of the full-expression}}
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sink((x = s).a); // Ok
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return *((x = s).a); // Ok
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}
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244
clang/test/C/C11/n1285_1.c
Normal file
244
clang/test/C/C11/n1285_1.c
Normal file
@ -0,0 +1,244 @@
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// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
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// RUN: %clang_cc1 -std=c99 -Wno-dangling -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK
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// RUN: %clang_cc1 -std=c11 -Wno-dangling -emit-llvm -o - %s | FileCheck %s --check-prefix=CHECK
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// RUN: %clang_cc1 -std=c11 -O2 -disable-llvm-passes -Wno-dangling -emit-llvm -o - %s | FileCheck %s --check-prefix=C11-O2
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// Ensure that codegen for temporary lifetimes makes sense.
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struct X { int a[5]; };
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struct X f(void);
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// CHECK-LABEL: define dso_local i32 @func_return(
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// CHECK-SAME: ) #[[ATTR0:[0-9]+]] {
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// CHECK-NEXT: [[ENTRY:.*:]]
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// CHECK-NEXT: [[P:%.*]] = alloca ptr, align 8
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// CHECK-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X:%.*]], align 4
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// CHECK-NEXT: call void @f(ptr dead_on_unwind writable sret([[STRUCT_X]]) align 4 [[REF_TMP]])
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// CHECK-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
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// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
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// CHECK-NEXT: store ptr [[ARRAYDECAY]], ptr [[P]], align 8
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// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr [[P]], align 8
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// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4
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// CHECK-NEXT: ret i32 [[TMP1]]
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//
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// C11-O2-LABEL: define dso_local i32 @func_return(
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// C11-O2-SAME: ) #[[ATTR0:[0-9]+]] {
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// C11-O2-NEXT: [[ENTRY:.*:]]
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// C11-O2-NEXT: [[P:%.*]] = alloca ptr, align 8
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// C11-O2-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X:%.*]], align 4
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// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 8, ptr [[P]]) #[[ATTR5:[0-9]+]]
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// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
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// C11-O2-NEXT: call void @f(ptr dead_on_unwind writable sret([[STRUCT_X]]) align 4 [[REF_TMP]])
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// C11-O2-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
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// C11-O2-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
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// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
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// C11-O2-NEXT: store ptr [[ARRAYDECAY]], ptr [[P]], align 8, !tbaa [[TBAA3:![0-9]+]]
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// C11-O2-NEXT: [[TMP0:%.*]] = load ptr, ptr [[P]], align 8, !tbaa [[TBAA3]]
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// C11-O2-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4, !tbaa [[TBAA8:![0-9]+]]
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// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 8, ptr [[P]]) #[[ATTR5]]
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// C11-O2-NEXT: ret i32 [[TMP1]]
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//
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int func_return(void) {
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int *p = f().a;
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return *p;
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}
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// CHECK-LABEL: define dso_local i32 @ternary(
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// CHECK-SAME: ) #[[ATTR0]] {
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// CHECK-NEXT: [[ENTRY:.*:]]
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// CHECK-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X:%.*]], align 4
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// CHECK-NEXT: [[Q:%.*]] = alloca ptr, align 8
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// CHECK-NEXT: [[DOTCOMPOUNDLITERAL:%.*]] = alloca [[STRUCT_X]], align 4
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// CHECK-NEXT: br i1 true, label %[[COND_TRUE:.*]], label %[[COND_FALSE:.*]]
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// CHECK: [[COND_TRUE]]:
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// CHECK-NEXT: call void @llvm.memset.p0.i64(ptr align 4 [[REF_TMP]], i8 0, i64 20, i1 false)
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// CHECK-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
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// CHECK-NEXT: br label %[[COND_END:.*]]
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// CHECK: [[COND_FALSE]]:
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// CHECK-NEXT: call void @f(ptr dead_on_unwind writable sret([[STRUCT_X]]) align 4 [[REF_TMP]])
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// CHECK-NEXT: br label %[[COND_END]]
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// CHECK: [[COND_END]]:
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// CHECK-NEXT: [[A1:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
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// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A1]], i64 0, i64 0
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// CHECK-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8
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// CHECK-NEXT: call void @llvm.memset.p0.i64(ptr align 4 [[DOTCOMPOUNDLITERAL]], i8 0, i64 20, i1 false)
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// CHECK-NEXT: [[A2:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[DOTCOMPOUNDLITERAL]], i32 0, i32 0
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// CHECK-NEXT: [[A3:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[DOTCOMPOUNDLITERAL]], i32 0, i32 0
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// CHECK-NEXT: [[ARRAYDECAY4:%.*]] = getelementptr inbounds [5 x i32], ptr [[A3]], i64 0, i64 0
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// CHECK-NEXT: store ptr [[ARRAYDECAY4]], ptr [[Q]], align 8
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// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8
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// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4
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// CHECK-NEXT: [[TMP2:%.*]] = load ptr, ptr [[Q]], align 8
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// CHECK-NEXT: [[TMP3:%.*]] = load i32, ptr [[TMP2]], align 4
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// CHECK-NEXT: [[ADD:%.*]] = add nsw i32 [[TMP1]], [[TMP3]]
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// CHECK-NEXT: ret i32 [[ADD]]
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//
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// C11-O2-LABEL: define dso_local i32 @ternary(
|
||||
// C11-O2-SAME: ) #[[ATTR0]] {
|
||||
// C11-O2-NEXT: [[ENTRY:.*:]]
|
||||
// C11-O2-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// C11-O2-NEXT: [[Q:%.*]] = alloca ptr, align 8
|
||||
// C11-O2-NEXT: [[DOTCOMPOUNDLITERAL:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: br i1 true, label %[[COND_TRUE:.*]], label %[[COND_FALSE:.*]]
|
||||
// C11-O2: [[COND_TRUE]]:
|
||||
// C11-O2-NEXT: call void @llvm.memset.p0.i64(ptr align 4 [[REF_TMP]], i8 0, i64 20, i1 false)
|
||||
// C11-O2-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// C11-O2-NEXT: br label %[[COND_END:.*]]
|
||||
// C11-O2: [[COND_FALSE]]:
|
||||
// C11-O2-NEXT: call void @f(ptr dead_on_unwind writable sret([[STRUCT_X]]) align 4 [[REF_TMP]])
|
||||
// C11-O2-NEXT: br label %[[COND_END]]
|
||||
// C11-O2: [[COND_END]]:
|
||||
// C11-O2-NEXT: [[A1:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A1]], i64 0, i64 0
|
||||
// C11-O2-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 8, ptr [[Q]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.memset.p0.i64(ptr align 4 [[DOTCOMPOUNDLITERAL]], i8 0, i64 20, i1 false)
|
||||
// C11-O2-NEXT: [[A2:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[DOTCOMPOUNDLITERAL]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[A3:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[DOTCOMPOUNDLITERAL]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[ARRAYDECAY4:%.*]] = getelementptr inbounds [5 x i32], ptr [[A3]], i64 0, i64 0
|
||||
// C11-O2-NEXT: store ptr [[ARRAYDECAY4]], ptr [[Q]], align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4, !tbaa [[TBAA8]]
|
||||
// C11-O2-NEXT: [[TMP2:%.*]] = load ptr, ptr [[Q]], align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP3:%.*]] = load i32, ptr [[TMP2]], align 4, !tbaa [[TBAA8]]
|
||||
// C11-O2-NEXT: [[ADD:%.*]] = add nsw i32 [[TMP1]], [[TMP3]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 8, ptr [[Q]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: ret i32 [[ADD]]
|
||||
//
|
||||
int ternary(void) {
|
||||
extern int *p;
|
||||
p = (1 ? (struct X){ 0 } : f()).a;
|
||||
int *q = 1 ? (struct X){ 0 }.a : f().a;
|
||||
|
||||
return *p + *q;
|
||||
}
|
||||
|
||||
// CHECK-LABEL: define dso_local i32 @comma(
|
||||
// CHECK-SAME: ) #[[ATTR0]] {
|
||||
// CHECK-NEXT: [[ENTRY:.*:]]
|
||||
// CHECK-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// CHECK-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false)
|
||||
// CHECK-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// CHECK-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4
|
||||
// CHECK-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
// C11-O2-LABEL: define dso_local i32 @comma(
|
||||
// C11-O2-SAME: ) #[[ATTR0]] {
|
||||
// C11-O2-NEXT: [[ENTRY:.*:]]
|
||||
// C11-O2-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// C11-O2-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false), !tbaa.struct [[TBAA_STRUCT10:![0-9]+]]
|
||||
// C11-O2-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// C11-O2-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4, !tbaa [[TBAA8]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
int comma(void) {
|
||||
struct X x;
|
||||
extern int *p;
|
||||
p = ((void)0, x).a;
|
||||
return *p;
|
||||
}
|
||||
|
||||
// CHECK-LABEL: define dso_local i32 @cast(
|
||||
// CHECK-SAME: ) #[[ATTR0]] {
|
||||
// CHECK-NEXT: [[ENTRY:.*:]]
|
||||
// CHECK-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// CHECK-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false)
|
||||
// CHECK-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// CHECK-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4
|
||||
// CHECK-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
// C11-O2-LABEL: define dso_local i32 @cast(
|
||||
// C11-O2-SAME: ) #[[ATTR0]] {
|
||||
// C11-O2-NEXT: [[ENTRY:.*:]]
|
||||
// C11-O2-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// C11-O2-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false), !tbaa.struct [[TBAA_STRUCT10]]
|
||||
// C11-O2-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// C11-O2-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4, !tbaa [[TBAA8]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
int cast(void) {
|
||||
struct X x;
|
||||
extern int *p;
|
||||
p = ((struct X)x).a;
|
||||
return *p;
|
||||
}
|
||||
|
||||
// CHECK-LABEL: define dso_local i32 @assign(
|
||||
// CHECK-SAME: ) #[[ATTR0]] {
|
||||
// CHECK-NEXT: [[ENTRY:.*:]]
|
||||
// CHECK-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// CHECK-NEXT: [[S:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// CHECK-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[X]], ptr align 4 [[S]], i64 20, i1 false)
|
||||
// CHECK-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false)
|
||||
// CHECK-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// CHECK-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// CHECK-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8
|
||||
// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4
|
||||
// CHECK-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
// C11-O2-LABEL: define dso_local i32 @assign(
|
||||
// C11-O2-SAME: ) #[[ATTR0]] {
|
||||
// C11-O2-NEXT: [[ENTRY:.*:]]
|
||||
// C11-O2-NEXT: [[X:%.*]] = alloca [[STRUCT_X:%.*]], align 4
|
||||
// C11-O2-NEXT: [[S:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// C11-O2-NEXT: [[REF_TMP:%.*]] = alloca [[STRUCT_X]], align 4
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[S]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.start.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[X]], ptr align 4 [[S]], i64 20, i1 false), !tbaa.struct [[TBAA_STRUCT10]]
|
||||
// C11-O2-NEXT: call void @llvm.memcpy.p0.p0.i64(ptr align 4 [[REF_TMP]], ptr align 4 [[X]], i64 20, i1 false), !tbaa.struct [[TBAA_STRUCT10]]
|
||||
// C11-O2-NEXT: [[A:%.*]] = getelementptr inbounds nuw [[STRUCT_X]], ptr [[REF_TMP]], i32 0, i32 0
|
||||
// C11-O2-NEXT: [[ARRAYDECAY:%.*]] = getelementptr inbounds [5 x i32], ptr [[A]], i64 0, i64 0
|
||||
// C11-O2-NEXT: store ptr [[ARRAYDECAY]], ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[REF_TMP]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: [[TMP0:%.*]] = load ptr, ptr @p, align 8, !tbaa [[TBAA3]]
|
||||
// C11-O2-NEXT: [[TMP1:%.*]] = load i32, ptr [[TMP0]], align 4, !tbaa [[TBAA8]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[S]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: call void @llvm.lifetime.end.p0(i64 20, ptr [[X]]) #[[ATTR5]]
|
||||
// C11-O2-NEXT: ret i32 [[TMP1]]
|
||||
//
|
||||
int assign(void) {
|
||||
struct X x, s;
|
||||
extern int *p;
|
||||
p = (x = s).a;
|
||||
return *p;
|
||||
}
|
||||
//.
|
||||
// C11-O2: [[TBAA3]] = !{[[META4:![0-9]+]], [[META4]], i64 0}
|
||||
// C11-O2: [[META4]] = !{!"p1 int", [[META5:![0-9]+]], i64 0}
|
||||
// C11-O2: [[META5]] = !{!"any pointer", [[META6:![0-9]+]], i64 0}
|
||||
// C11-O2: [[META6]] = !{!"omnipotent char", [[META7:![0-9]+]], i64 0}
|
||||
// C11-O2: [[META7]] = !{!"Simple C/C++ TBAA"}
|
||||
// C11-O2: [[TBAA8]] = !{[[META9:![0-9]+]], [[META9]], i64 0}
|
||||
// C11-O2: [[META9]] = !{!"int", [[META6]], i64 0}
|
||||
// C11-O2: [[TBAA_STRUCT10]] = !{i64 0, i64 20, [[META11:![0-9]+]]}
|
||||
// C11-O2: [[META11]] = !{[[META6]], [[META6]], i64 0}
|
||||
//.
|
||||
@ -27,7 +27,7 @@ void testva (int n, ...) {
|
||||
va_start(ap,n);
|
||||
// CHECK: [[AP:%[a-z0-9]+]] = alloca ptr, align 4
|
||||
// CHECK: [[V5:%[a-z0-9]+]] = alloca %struct.x, align 4
|
||||
// CHECK: [[TMP:%[a-z0-9]+]] = alloca [4 x i32], align 4
|
||||
// CHECK: [[TMP:%[a-z0-9.]+]] = alloca [4 x i32], align 4
|
||||
// CHECK: call void @llvm.va_start.p0(ptr [[AP]])
|
||||
|
||||
char* v1 = va_arg (ap, char*);
|
||||
|
||||
@ -23,7 +23,8 @@ typedef struct _GLKMatrix4 GLKMatrix4;
|
||||
}
|
||||
@end
|
||||
|
||||
// CHECK: [[M:%.*]] = getelementptr inbounds nuw %struct._GLKMatrix4, ptr [[TMP:%.*]], i32 0, i32 0
|
||||
// CHECK: [[REF_TEMP:%.*]] = alloca %struct._GLKMatrix4, align 4
|
||||
// CHECK: [[M:%.*]] = getelementptr inbounds nuw %struct._GLKMatrix4, ptr [[REF_TEMP:%.*]], i32 0, i32 0
|
||||
// CHECK: [[ARRAYDECAY:%.*]] = getelementptr inbounds [16 x float], ptr [[M]], i64 0, i64 0
|
||||
// CHECK: [[SIX:%.*]] = load ptr, ptr @OBJC_SELECTOR_REFERENCES
|
||||
// CHECK: call void @objc_msgSend(ptr noundef [[SEVEN:%.*]], ptr noundef [[SIX]], ptr noundef [[ARRAYDECAY]])
|
||||
// CHECK: call void @objc_msgSend(ptr noundef [[SEVEN:%.*]], ptr noundef [[SIX]], ptr noundef [[ARRAYDECAY]])
|
||||
|
||||
@ -941,7 +941,7 @@ conformance.</p>
|
||||
<tr>
|
||||
<td>Extending the lifetime of temporary objects (factored approach)</td>
|
||||
<td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1285.htm">N1285</a></td>
|
||||
<td class="none" align="center">No</td>
|
||||
<td class="unreleased" align="center">Clang 21</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Requiring signed char to have no padding bits</td>
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user