[cfe-commits] r92753 - in /cfe/trunk: lib/AST/DeclCXX.cpp lib/AST/RecordLayoutBuilder.cpp lib/CodeGen/CGVtable.cpp lib/CodeGen/CodeGenModule.cpp lib/Sema/SemaDecl.cpp lib/Sema/SemaDeclCXX.cpp test/CodeGenCXX/vtable-key-function.cpp test/CodeGenCXX/vtable-linkage.cpp
Douglas Gregor
dgregor at apple.com
Tue Jan 5 11:06:32 PST 2010
Author: dgregor
Date: Tue Jan 5 13:06:31 2010
New Revision: 92753
URL: http://llvm.org/viewvc/llvm-project?rev=92753&view=rev
Log:
Improve key-function computation for templates. In particular:
- All classes can have a key function; templates don't change that.
non-template classes when computing the key function.
- We always mark all of the virtual member functions of class
template instantiations.
- The vtable for an instantiation of a class template has weak
linkage.
We could probably use available_externally linkage for vtables of
classes instantiated by explicit instantiation declarations (extern
templates), but GCC doesn't do this and I'm not 100% that the ABI
permits it.
Modified:
cfe/trunk/lib/AST/DeclCXX.cpp
cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
cfe/trunk/lib/CodeGen/CGVtable.cpp
cfe/trunk/lib/CodeGen/CodeGenModule.cpp
cfe/trunk/lib/Sema/SemaDecl.cpp
cfe/trunk/lib/Sema/SemaDeclCXX.cpp
cfe/trunk/test/CodeGenCXX/vtable-key-function.cpp
cfe/trunk/test/CodeGenCXX/vtable-linkage.cpp
Modified: cfe/trunk/lib/AST/DeclCXX.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/DeclCXX.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/AST/DeclCXX.cpp (original)
+++ cfe/trunk/lib/AST/DeclCXX.cpp Tue Jan 5 13:06:31 2010
@@ -643,23 +643,15 @@
return C.getPointerType(ClassTy);
}
-static bool MethodHasBody(const CXXMethodDecl *MD, const FunctionDecl *&fn) {
- // Simple case: function has a body
- if (MD->getBody(fn))
- return true;
-
- // Complex case: function is an instantiation of a function which has a
- // body, but the definition hasn't been instantiated.
- const FunctionDecl *PatternDecl = MD->getTemplateInstantiationPattern();
- if (PatternDecl && PatternDecl->getBody(fn))
- return true;
-
- return false;
-}
-
bool CXXMethodDecl::hasInlineBody() const {
+ // If this function is a template instantiation, look at the template from
+ // which it was instantiated.
+ const FunctionDecl *CheckFn = getTemplateInstantiationPattern();
+ if (!CheckFn)
+ CheckFn = this;
+
const FunctionDecl *fn;
- return MethodHasBody(this, fn) && !fn->isOutOfLine();
+ return CheckFn->getBody(fn) && !fn->isOutOfLine();
}
CXXBaseOrMemberInitializer::
Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Tue Jan 5 13:06:31 2010
@@ -719,11 +719,6 @@
// If a class isnt' polymorphic it doesn't have a key function.
if (!RD->isPolymorphic())
return 0;
-
- // A class template specialization or instantation does not have a key
- // function.
- if (RD->getTemplateSpecializationKind() != TSK_Undeclared)
- return 0;
// A class inside an anonymous namespace doesn't have a key function. (Or
// at least, there's no point to assigning a key function to such a class;
@@ -741,13 +736,13 @@
if (MD->isPure())
continue;
- if (MD->isInlineSpecified())
- continue;
-
// Ignore implicit member functions, they are always marked as inline, but
// they don't have a body until they're defined.
if (MD->isImplicit())
continue;
+
+ if (MD->isInlineSpecified())
+ continue;
if (MD->hasInlineBody())
continue;
Modified: cfe/trunk/lib/CodeGen/CGVtable.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGVtable.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGVtable.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGVtable.cpp Tue Jan 5 13:06:31 2010
@@ -1493,8 +1493,22 @@
llvm::GlobalVariable::LinkageTypes Linkage;
if (RD->isInAnonymousNamespace() || !RD->hasLinkage())
Linkage = llvm::GlobalVariable::InternalLinkage;
- else if (KeyFunction && !MD->isInlined())
- Linkage = llvm::GlobalVariable::ExternalLinkage;
+ else if (KeyFunction && !MD->isInlined()) {
+ switch (MD->getTemplateSpecializationKind()) {
+ case TSK_Undeclared:
+ case TSK_ExplicitSpecialization:
+ Linkage = llvm::GlobalVariable::ExternalLinkage;
+ break;
+
+ case TSK_ImplicitInstantiation:
+ case TSK_ExplicitInstantiationDeclaration:
+ // FIXME: could an explicit instantiation declaration imply
+ // available_externally linkage?
+ case TSK_ExplicitInstantiationDefinition:
+ Linkage = llvm::GlobalVariable::WeakODRLinkage;
+ break;
+ }
+ }
else
Linkage = llvm::GlobalVariable::WeakODRLinkage;
Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Tue Jan 5 13:06:31 2010
@@ -547,7 +547,8 @@
const CXXRecordDecl *RD = MD->getParent();
if (MD->isOutOfLine() && RD->isDynamicClass()) {
const CXXMethodDecl *KeyFunction = getContext().getKeyFunction(RD);
- if (KeyFunction == MD->getCanonicalDecl())
+ if (KeyFunction &&
+ KeyFunction->getCanonicalDecl() == MD->getCanonicalDecl())
return false;
}
}
Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Tue Jan 5 13:06:31 2010
@@ -3749,7 +3749,7 @@
if (getLangOptions().CPlusPlus) {
// Make sure we mark the destructor as used if necessary.
QualType InitType = VDecl->getType();
- if (const ArrayType *Array = Context.getAsArrayType(InitType))
+ while (const ArrayType *Array = Context.getAsArrayType(InitType))
InitType = Context.getBaseElementType(Array);
if (InitType->isRecordType())
FinalizeVarWithDestructor(VDecl, InitType);
Modified: cfe/trunk/lib/Sema/SemaDeclCXX.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDeclCXX.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDeclCXX.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDeclCXX.cpp Tue Jan 5 13:06:31 2010
@@ -5702,19 +5702,31 @@
ClassesWithUnmarkedVirtualMembers.insert(std::make_pair(RD, Loc));
return;
}
-
- const CXXMethodDecl *KeyFunction = Context.getKeyFunction(RD);
- if (!KeyFunction) {
- // This record does not have a key function, so we assume that the vtable
- // will be emitted when it's used by the constructor.
- if (!isa<CXXConstructorDecl>(MD))
+ switch (RD->getTemplateSpecializationKind()) {
+ case TSK_Undeclared:
+ case TSK_ExplicitSpecialization: {
+ const CXXMethodDecl *KeyFunction = Context.getKeyFunction(RD);
+
+ if (!KeyFunction) {
+ // This record does not have a key function, so we assume that the vtable
+ // will be emitted when it's used by the constructor.
+ if (!isa<CXXConstructorDecl>(MD))
+ return;
+ } else if (KeyFunction->getCanonicalDecl() != MD->getCanonicalDecl()) {
+ // We don't have the right key function.
return;
- } else if (KeyFunction->getCanonicalDecl() != MD->getCanonicalDecl()) {
- // We don't have the right key function.
- return;
+ }
+ break;
}
-
+
+ case TSK_ImplicitInstantiation:
+ case TSK_ExplicitInstantiationDeclaration:
+ case TSK_ExplicitInstantiationDefinition:
+ // Always mark the virtual members of an instantiated template.
+ break;
+ }
+
// Mark the members as referenced.
MarkVirtualMembersReferenced(Loc, RD);
ClassesWithUnmarkedVirtualMembers.erase(RD);
Modified: cfe/trunk/test/CodeGenCXX/vtable-key-function.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/vtable-key-function.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/vtable-key-function.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/vtable-key-function.cpp Tue Jan 5 13:06:31 2010
@@ -13,3 +13,21 @@
A::A() { }
A::A(int) { }
}
+
+// Make sure that we don't assert when building the vtable for a class
+// template specialization or explicit instantiation with a key
+// function.
+template<typename T>
+struct Base {
+ virtual ~Base();
+};
+
+template<typename T>
+struct Derived : public Base<T> { };
+
+template<>
+struct Derived<char> : public Base<char> {
+ virtual void anchor();
+};
+
+void Derived<char>::anchor() { }
Modified: cfe/trunk/test/CodeGenCXX/vtable-linkage.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/vtable-linkage.cpp?rev=92753&r1=92752&r2=92753&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/vtable-linkage.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/vtable-linkage.cpp Tue Jan 5 13:06:31 2010
@@ -30,6 +30,30 @@
static struct : D { } e;
+template<typename T>
+struct E {
+ virtual ~E();
+};
+
+template<typename T> E<T>::~E() { }
+
+template<>
+struct E<char> {
+ virtual void anchor();
+};
+
+void E<char>::anchor() { }
+
+template struct E<short>;
+extern template struct E<int>;
+
+void use_E() {
+ E<int> ei;
+ (void)ei;
+ E<long> el;
+ (void)el;
+}
+
// B has a key function that is not defined in this translation unit so its vtable
// has external linkage.
// CHECK: @_ZTV1B = external constant
@@ -45,14 +69,36 @@
// CHECK: @_ZTI1D = constant
// CHECK: @_ZTV1D = constant
+// E<char> is an explicit specialization with a key function defined
+// in this translation unit, so its vtable should have external
+// linkage.
+// CHECK: @_ZTV1EIcE = constant
+
+// E<short> is an explicit template instantiation with a key function
+// defined in this translation unit, so its vtable should have
+// weak_odr linkage.
+// CHECK: @_ZTV1EIsE = weak_odr constant
+
+// E<long> is an implicit template instantiation with a key function
+// defined in this translation unit, so its vtable should have
+// weak_odr linkage.
+// CHECK: @_ZTV1EIlE = weak_odr constant
+
// The anonymous struct for e has no linkage, so the vtable should have
// internal linkage.
// CHECK: @"_ZTS3$_0" = internal constant
// CHECK: @"_ZTI3$_0" = internal constant
// CHECK: @"_ZTV3$_0" = internal constant
+// E<int> is an explicit template instantiation declaration. It has a
+// key function that is not instantiation, so we should only reference
+// its vtable, not define it.
+// CHECK: @_ZTV1EIiE = external constant
+
// The A vtable should have internal linkage since it is inside an anonymous
// namespace.
// CHECK: @_ZTSN12_GLOBAL__N_11AE = internal constant
// CHECK: @_ZTIN12_GLOBAL__N_11AE = internal constant
// CHECK: @_ZTVN12_GLOBAL__N_11AE = internal constant
+
+
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