microsoft
/
clang-1
зеркало из https://github.com/microsoft/clang-1.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность

Revert r117644, "Apply visibility in IR gen to variables that are merely 

declared", it breaks things.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@117653 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Daniel Dunbar 2010-10-29 15:19:36 +00:00
Родитель 14e1bc9201
Коммит 034f55c1eb
3 изменённых файлов: 61 добавлений и 176 удалений
Показать статистику Скачать Patch файл Скачать Diff файл Показать все файлы Свернуть все файлы

155
lib/AST/Decl.cpp
Просмотреть файл

@ -140,25 +140,16 @@ static LVPair getLVForTemplateArgumentList(const TemplateArgumentList &TArgs) {
TArgs.flat_size());
}
/// Answers whether the given class, or any containing class, has an
/// explicit visibility attribute.
static bool HasExplicitVisibilityInHierarchy(const RecordDecl *RD) {
if (RD->hasAttr<VisibilityAttr>()) return true;
if (const RecordDecl *Parent = dyn_cast<RecordDecl>(RD->getDeclContext()))
return HasExplicitVisibilityInHierarchy(Parent);
return false;
}
/// getLVForDecl - Get the cached linkage and visibility for the given
/// declaration.
///
/// \param ConsiderGlobalVisibility - Whether to honor global visibility
/// settings. This is generally false when computing the visibility
/// of the context of a declaration.
static LVPair getLVForDecl(const NamedDecl *D, bool ConsiderGlobalVisibility);
/// \param ConsiderGlobalSettings - Whether to honor global visibility
/// settings. This is false when computing the visibility of the
/// context of a declaration with an explicit visibility attribute.
static LVPair getLVForDecl(const NamedDecl *D, bool ConsiderGlobalSettings);
static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
bool ConsiderGlobalVisibility) {
bool ConsiderGlobalSettings) {
assert(D->getDeclContext()->getRedeclContext()->isFileContext() &&
"Not a name having namespace scope");
ASTContext &Context = D->getASTContext();
@ -225,6 +216,10 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
// external.
LVPair LV(ExternalLinkage, DefaultVisibility);
// We ignore -fvisibility on non-definitions and explicit
// instantiation declarations.
bool ConsiderDashFVisibility = ConsiderGlobalSettings;
// C++ [basic.link]p4:
// A name having namespace scope has external linkage if it is the
@ -232,9 +227,6 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
//
// - an object or reference, unless it has internal linkage; or
if (const VarDecl *Var = dyn_cast<VarDecl>(D)) {
// GCC applies the following optimization to variables and static
// data members, but not to functions:
//
// Modify the variable's LV by the LV of its type unless this is
// C or extern "C". This follows from [basic.link]p9:
// A type without linkage shall not be used as the type of a
@ -281,9 +273,6 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
if (PrevLV.first) LV.first = PrevLV.first;
LV.second = minVisibility(LV.second, PrevLV.second);
}
// Don't consider -fvisibility for extern declarations.
ConsiderGlobalVisibility = false;
}
// - a function, unless it has internal linkage; or
@ -326,12 +315,11 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
if (SpecInfo->getTemplateSpecializationKind()
== TSK_ExplicitInstantiationDeclaration)
ConsiderGlobalVisibility = false;
ConsiderDashFVisibility = false;
}
// -fvisibility only applies to function definitions.
if (ConsiderGlobalVisibility)
ConsiderGlobalVisibility = Function->hasBody();
if (ConsiderDashFVisibility)
ConsiderDashFVisibility = Function->hasBody();
// - a named class (Clause 9), or an unnamed class defined in a
// typedef declaration in which the class has the typedef name
@ -358,12 +346,12 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
if (Spec->getTemplateSpecializationKind()
== TSK_ExplicitInstantiationDeclaration)
ConsiderGlobalVisibility = false;
ConsiderDashFVisibility = false;
}
// Consider -fvisibility unless the type has C linkage.
if (ConsiderGlobalVisibility)
ConsiderGlobalVisibility =
if (ConsiderDashFVisibility)
ConsiderDashFVisibility =
(Context.getLangOptions().CPlusPlus &&
!Tag->getDeclContext()->isExternCContext());
@ -413,7 +401,7 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
// If we have an explicit visibility attribute, merge that in.
if (ExplicitVisibility)
StandardV = GetVisibilityFromAttr(ExplicitVisibility);
else if (ConsiderGlobalVisibility)
else if (ConsiderDashFVisibility)
StandardV = Context.getLangOptions().getVisibilityMode();
else
StandardV = DefaultVisibility; // no-op
@ -425,7 +413,7 @@ static LVPair getLVForNamespaceScopeDecl(const NamedDecl *D,
}
static LVPair getLVForClassMember(const NamedDecl *D,
bool ConsiderGlobalVisibility) {
bool ConsiderGlobalSettings) {
// Only certain class members have linkage. Note that fields don't
// really have linkage, but it's convenient to say they do for the
// purposes of calculating linkage of pointer-to-data-member
@ -437,9 +425,12 @@ static LVPair getLVForClassMember(const NamedDecl *D,
(D->getDeclName() || cast<TagDecl>(D)->getTypedefForAnonDecl()))))
return LVPair(NoLinkage, DefaultVisibility);
// If we have an explicit visibility attribute, merge that in.
const VisibilityAttr *VA = GetExplicitVisibility(D);
// Class members only have linkage if their class has external linkage.
// Always ignore global visibility settings during this.
LVPair ClassLV = getLVForDecl(cast<RecordDecl>(D->getDeclContext()), false);
LVPair ClassLV = getLVForDecl(cast<RecordDecl>(D->getDeclContext()),
ConsiderGlobalSettings && !VA);
if (!isExternalLinkage(ClassLV.first))
return LVPair(NoLinkage, DefaultVisibility);
@ -449,21 +440,19 @@ static LVPair getLVForClassMember(const NamedDecl *D,
// Start with the class's linkage and visibility.
LVPair LV = ClassLV;
if (VA) LV.second = minVisibility(LV.second, GetVisibilityFromAttr(VA));
// If we have an explicit visibility attribute, merge that in and
// ignore global visibility settings.
const VisibilityAttr *VA = GetExplicitVisibility(D);
if (VA) {
LV.second = minVisibility(LV.second, GetVisibilityFromAttr(VA));
ConsiderGlobalVisibility = false;
// If it's a variable declaration and we don't have an explicit
// visibility attribute, apply the LV from its type.
// See the comment about namespace-scope variable decls above.
if (!VA && isa<VarDecl>(D)) {
LVPair TypeLV = cast<VarDecl>(D)->getType()->getLinkageAndVisibility();
if (TypeLV.first != ExternalLinkage)
LV.first = minLinkage(LV.first, UniqueExternalLinkage);
LV.second = minVisibility(LV.second, TypeLV.second);
}
bool HasExplicitVisibility = (VA ||
HasExplicitVisibilityInHierarchy(cast<RecordDecl>(D->getDeclContext())));
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
TemplateSpecializationKind TSK = TSK_Undeclared;
// If this is a method template specialization, use the linkage for
// the template parameters and arguments.
if (FunctionTemplateSpecializationInfo *Spec
@ -471,80 +460,24 @@ static LVPair getLVForClassMember(const NamedDecl *D,
LV = merge(LV, getLVForTemplateArgumentList(*Spec->TemplateArguments));
LV = merge(LV, getLVForTemplateParameterList(
Spec->getTemplate()->getTemplateParameters()));
TSK = Spec->getTemplateSpecializationKind();
} else if (MemberSpecializationInfo *MSI =
MD->getMemberSpecializationInfo()) {
TSK = MSI->getTemplateSpecializationKind();
}
// Ignore global visibility if it's an extern template.
if (ConsiderGlobalVisibility)
ConsiderGlobalVisibility = (TSK != TSK_ExplicitInstantiationDeclaration);
// If we're paying attention to global visibility, apply
// -finline-visibility-hidden if this is an inline method.
//
// Note that we ignore the existence of visibility attributes
// on containing classes when deciding whether to do this.
if (ConsiderGlobalVisibility && MD->isInlined() &&
MD->getASTContext().getLangOptions().InlineVisibilityHidden)
// If -fvisibility-inlines-hidden was provided, then inline C++
// member functions get "hidden" visibility if they don't have an
// explicit visibility attribute.
if (ConsiderGlobalSettings && !VA && MD->isInlined() &&
LV.second > HiddenVisibility &&
D->getASTContext().getLangOptions().InlineVisibilityHidden &&
MD->getTemplateSpecializationKind()
!= TSK_ExplicitInstantiationDeclaration)
LV.second = HiddenVisibility;
// Note that in contrast to basically every other situation, we
// *do* apply -fvisibility to method declarations.
} else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
TemplateSpecializationKind TSK = TSK_Undeclared;
if (const ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(RD)) {
// Merge template argument/parameter information for member
// class template specializations.
LV = merge(LV, getLVForTemplateArgumentList(Spec->getTemplateArgs()));
LV = merge(LV, getLVForTemplateParameterList(
// Similarly for member class template specializations.
} else if (const ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(D)) {
LV = merge(LV, getLVForTemplateArgumentList(Spec->getTemplateArgs()));
LV = merge(LV, getLVForTemplateParameterList(
Spec->getSpecializedTemplate()->getTemplateParameters()));
TSK = Spec->getTemplateSpecializationKind();
} else if (MemberSpecializationInfo *MSI =
RD->getMemberSpecializationInfo()) {
TSK = MSI->getTemplateSpecializationKind();
}
// Ignore global visibility if it's an extern template.
if (ConsiderGlobalVisibility)
ConsiderGlobalVisibility = (TSK != TSK_ExplicitInstantiationDeclaration);
// Static data members.
} else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
// If we don't have explicit visibility information in the
// hierarchy, apply the LV from its type. See the comment about
// namespace-scope variables for justification for this
// optimization.
if (!HasExplicitVisibility) {
LVPair TypeLV = VD->getType()->getLinkageAndVisibility();
if (TypeLV.first != ExternalLinkage)
LV.first = minLinkage(LV.first, UniqueExternalLinkage);
LV.second = minVisibility(LV.second, TypeLV.second);
}
// Ignore global visibility if it's an extern template or
// just a declaration.
if (ConsiderGlobalVisibility)
ConsiderGlobalVisibility =
(VD->getDefinition() &&
VD->getTemplateSpecializationKind()
!= TSK_ExplicitInstantiationDeclaration);
}
// Suppress -fvisibility if we have explicit visibility on any of
// our ancestors.
ConsiderGlobalVisibility &= !HasExplicitVisibility;
// Apply -fvisibility if desired.
if (ConsiderGlobalVisibility && LV.second != HiddenVisibility) {
LV.second = minVisibility(LV.second,
D->getASTContext().getLangOptions().getVisibilityMode());
}
return LV;

40
lib/CodeGen/CodeGenModule.cpp
Просмотреть файл

@ -164,17 +164,6 @@ void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type,
getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
}
static llvm::GlobalValue::VisibilityTypes GetLLVMVisibility(Visibility V) {
switch (V) {
case DefaultVisibility: return llvm::GlobalValue::DefaultVisibility;
case HiddenVisibility: return llvm::GlobalValue::HiddenVisibility;
case ProtectedVisibility: return llvm::GlobalValue::ProtectedVisibility;
}
llvm_unreachable("unknown visibility!");
return llvm::GlobalValue::DefaultVisibility;
}
void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
const NamedDecl *D) const {
// Internal definitions always have default visibility.
@ -183,7 +172,15 @@ void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
return;
}
GV->setVisibility(GetLLVMVisibility(D->getVisibility()));
switch (D->getVisibility()) {
case DefaultVisibility:
return GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
case HiddenVisibility:
return GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
case ProtectedVisibility:
return GV->setVisibility(llvm::GlobalValue::ProtectedVisibility);
}
llvm_unreachable("unknown visibility!");
}
/// Set the symbol visibility of type information (vtable and RTTI)
@ -937,18 +934,15 @@ CodeGenModule::GetOrCreateLLVMGlobal(llvm::StringRef MangledName,
// handling.
GV->setConstant(DeclIsConstantGlobal(Context, D));
// Set linkage and visibility in case we never see a definition.
std::pair<Linkage,Visibility> LV = D->getLinkageAndVisibility();
if (LV.first != ExternalLinkage) {
GV->setLinkage(llvm::GlobalValue::InternalLinkage);
} else {
if (D->hasAttr<DLLImportAttr>())
GV->setLinkage(llvm::GlobalValue::DLLImportLinkage);
else if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakImportAttr>())
GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
// FIXME: Merge with other attribute handling code.
if (D->getStorageClass() == SC_PrivateExtern)
GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
GV->setVisibility(GetLLVMVisibility(LV.second));
}
if (D->hasAttr<DLLImportAttr>())
GV->setLinkage(llvm::GlobalValue::DLLImportLinkage);
else if (D->hasAttr<WeakAttr>() ||
D->hasAttr<WeakImportAttr>())
GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
GV->setThreadLocal(D->isThreadSpecified());
}

42
test/CodeGenCXX/visibility.cpp
Просмотреть файл

@ -10,14 +10,6 @@
// CHECK: @_ZN5Test71bE = global
// CHECK: @test9_var = global
// CHECK-HIDDEN: @test9_var = global
// CHECK: @_ZN6Test121A6hiddenE = external hidden global
// CHECK: @_ZN6Test121A7visibleE = external global
// CHECK-HIDDEN: @_ZN6Test121A6hiddenE = external hidden global
// CHECK-HIDDEN: @_ZN6Test121A7visibleE = external global
// CHECK: @_ZN6Test131B1aE = hidden global
// CHECK: @_ZN6Test131C1aE = global
// CHECK-HIDDEN: @_ZN6Test131B1aE = hidden global
// CHECK-HIDDEN: @_ZN6Test131C1aE = global
// CHECK: @_ZTVN5Test63fooE = weak_odr hidden constant
namespace Test1 {
@ -173,37 +165,3 @@ namespace Test11 {
// CHECK-HIDDEN: define linkonce_odr hidden void @_ZN6Test111A3fooEv(
// CHECK-HIDDEN: define linkonce_odr void @_ZN6Test111A3barEv(
}
// Tested at top of file.
namespace Test12 {
struct A {
// This is hidden in all cases: the explicit attribute takes
// priority over -fvisibility on the parent.
static int hidden HIDDEN;
// This is default in all cases because it's only a declaration.
static int visible;
};
void test() {
A::hidden = 0;
A::visible = 0;
}
}
// Tested at top of file.
namespace Test13 {
struct HIDDEN A {};
// Should be hidden in all cases.
struct B {
static A a;
};
A B::a;
// Should be default in all cases.
struct DEFAULT C {
static A a;
};
A C::a;
};