tejohnson updated this revision to Diff 307404.
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CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D91676/new/
https://reviews.llvm.org/D91676
Files:
clang/lib/CodeGen/CGVTables.cpp
clang/lib/CodeGen/CodeGenModule.h
clang/lib/CodeGen/MicrosoftCXXABI.cpp
Index: clang/lib/CodeGen/MicrosoftCXXABI.cpp
===================================================================
--- clang/lib/CodeGen/MicrosoftCXXABI.cpp
+++ clang/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -1649,8 +1649,9 @@
// TODO: Should VirtualFunctionElimination also be supported here?
// See similar handling in CodeGenModule::EmitVTableTypeMetadata.
if (CGM.getCodeGenOpts().WholeProgramVTables) {
+ llvm::DenseSet<const CXXRecordDecl *> Visited;
llvm::GlobalObject::VCallVisibility TypeVis =
- CGM.GetVCallVisibilityLevel(RD);
+ CGM.GetVCallVisibilityLevel(RD, Visited);
if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
VTable->setVCallVisibilityMetadata(TypeVis);
}
Index: clang/lib/CodeGen/CodeGenModule.h
===================================================================
--- clang/lib/CodeGen/CodeGenModule.h
+++ clang/lib/CodeGen/CodeGenModule.h
@@ -1333,8 +1333,11 @@
/// a virtual function call could be made which ends up being dispatched to a
/// member function of this class. This scope can be wider than the
visibility
/// of the class itself when the class has a more-visible dynamic base class.
+ /// The client should pass in an empty Visited set, which is used to prevent
+ /// redundant recursive processing.
llvm::GlobalObject::VCallVisibility
- GetVCallVisibilityLevel(const CXXRecordDecl *RD);
+ GetVCallVisibilityLevel(const CXXRecordDecl *RD,
+ llvm::DenseSet<const CXXRecordDecl *> &Visited);
/// Emit type metadata for the given vtable using the given layout.
void EmitVTableTypeMetadata(const CXXRecordDecl *RD,
Index: clang/lib/CodeGen/CGVTables.cpp
===================================================================
--- clang/lib/CodeGen/CGVTables.cpp
+++ clang/lib/CodeGen/CGVTables.cpp
@@ -1294,8 +1294,16 @@
return !HasLTOVisibilityPublicStd(RD);
}
-llvm::GlobalObject::VCallVisibility
-CodeGenModule::GetVCallVisibilityLevel(const CXXRecordDecl *RD) {
+llvm::GlobalObject::VCallVisibility CodeGenModule::GetVCallVisibilityLevel(
+ const CXXRecordDecl *RD, llvm::DenseSet<const CXXRecordDecl *> &Visited) {
+ // If we have already visited this RD (which means this is a recursive call
+ // since the initial call should have an empty Visited set), return the max
+ // visibility. The recursive calls below compute the min between the result
+ // of the recursive call and the current TypeVis, so returning the max here
+ // ensures that it will have no effect on the current TypeVis.
+ if (!Visited.insert(RD).second)
+ return llvm::GlobalObject::VCallVisibilityTranslationUnit;
+
LinkageInfo LV = RD->getLinkageAndVisibility();
llvm::GlobalObject::VCallVisibility TypeVis;
if (!isExternallyVisible(LV.getLinkage()))
@@ -1307,13 +1315,15 @@
for (auto B : RD->bases())
if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
-
GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
+ TypeVis = std::min(
+ TypeVis,
+ GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl(), Visited));
for (auto B : RD->vbases())
if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
-
GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
+ TypeVis = std::min(
+ TypeVis,
+ GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl(), Visited));
return TypeVis;
}
@@ -1382,7 +1392,9 @@
if (getCodeGenOpts().VirtualFunctionElimination ||
getCodeGenOpts().WholeProgramVTables) {
- llvm::GlobalObject::VCallVisibility TypeVis = GetVCallVisibilityLevel(RD);
+ llvm::DenseSet<const CXXRecordDecl *> Visited;
+ llvm::GlobalObject::VCallVisibility TypeVis =
+ GetVCallVisibilityLevel(RD, Visited);
if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
VTable->setVCallVisibilityMetadata(TypeVis);
}
Index: clang/lib/CodeGen/MicrosoftCXXABI.cpp
===================================================================
--- clang/lib/CodeGen/MicrosoftCXXABI.cpp
+++ clang/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -1649,8 +1649,9 @@
// TODO: Should VirtualFunctionElimination also be supported here?
// See similar handling in CodeGenModule::EmitVTableTypeMetadata.
if (CGM.getCodeGenOpts().WholeProgramVTables) {
+ llvm::DenseSet<const CXXRecordDecl *> Visited;
llvm::GlobalObject::VCallVisibility TypeVis =
- CGM.GetVCallVisibilityLevel(RD);
+ CGM.GetVCallVisibilityLevel(RD, Visited);
if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
VTable->setVCallVisibilityMetadata(TypeVis);
}
Index: clang/lib/CodeGen/CodeGenModule.h
===================================================================
--- clang/lib/CodeGen/CodeGenModule.h
+++ clang/lib/CodeGen/CodeGenModule.h
@@ -1333,8 +1333,11 @@
/// a virtual function call could be made which ends up being dispatched to a
/// member function of this class. This scope can be wider than the visibility
/// of the class itself when the class has a more-visible dynamic base class.
+ /// The client should pass in an empty Visited set, which is used to prevent
+ /// redundant recursive processing.
llvm::GlobalObject::VCallVisibility
- GetVCallVisibilityLevel(const CXXRecordDecl *RD);
+ GetVCallVisibilityLevel(const CXXRecordDecl *RD,
+ llvm::DenseSet<const CXXRecordDecl *> &Visited);
/// Emit type metadata for the given vtable using the given layout.
void EmitVTableTypeMetadata(const CXXRecordDecl *RD,
Index: clang/lib/CodeGen/CGVTables.cpp
===================================================================
--- clang/lib/CodeGen/CGVTables.cpp
+++ clang/lib/CodeGen/CGVTables.cpp
@@ -1294,8 +1294,16 @@
return !HasLTOVisibilityPublicStd(RD);
}
-llvm::GlobalObject::VCallVisibility
-CodeGenModule::GetVCallVisibilityLevel(const CXXRecordDecl *RD) {
+llvm::GlobalObject::VCallVisibility CodeGenModule::GetVCallVisibilityLevel(
+ const CXXRecordDecl *RD, llvm::DenseSet<const CXXRecordDecl *> &Visited) {
+ // If we have already visited this RD (which means this is a recursive call
+ // since the initial call should have an empty Visited set), return the max
+ // visibility. The recursive calls below compute the min between the result
+ // of the recursive call and the current TypeVis, so returning the max here
+ // ensures that it will have no effect on the current TypeVis.
+ if (!Visited.insert(RD).second)
+ return llvm::GlobalObject::VCallVisibilityTranslationUnit;
+
LinkageInfo LV = RD->getLinkageAndVisibility();
llvm::GlobalObject::VCallVisibility TypeVis;
if (!isExternallyVisible(LV.getLinkage()))
@@ -1307,13 +1315,15 @@
for (auto B : RD->bases())
if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
- GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
+ TypeVis = std::min(
+ TypeVis,
+ GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl(), Visited));
for (auto B : RD->vbases())
if (B.getType()->getAsCXXRecordDecl()->isDynamicClass())
- TypeVis = std::min(TypeVis,
- GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl()));
+ TypeVis = std::min(
+ TypeVis,
+ GetVCallVisibilityLevel(B.getType()->getAsCXXRecordDecl(), Visited));
return TypeVis;
}
@@ -1382,7 +1392,9 @@
if (getCodeGenOpts().VirtualFunctionElimination ||
getCodeGenOpts().WholeProgramVTables) {
- llvm::GlobalObject::VCallVisibility TypeVis = GetVCallVisibilityLevel(RD);
+ llvm::DenseSet<const CXXRecordDecl *> Visited;
+ llvm::GlobalObject::VCallVisibility TypeVis =
+ GetVCallVisibilityLevel(RD, Visited);
if (TypeVis != llvm::GlobalObject::VCallVisibilityPublic)
VTable->setVCallVisibilityMetadata(TypeVis);
}
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