proxy->setVisibility(llvm::GlobalValue::HiddenVisibility);
proxy->setComdat(module.getOrInsertComdat(rttiProxyName));
}
+ // Do not instrument the rtti proxies with hwasan to avoid a duplicate
+ // symbol error. Aliases generated by hwasan will retain the same namebut
+ // the addresses they are set to may have different tags from different
+ // compilation units. We don't run into this without hwasan because the
+ // proxies are in comdat groups, but those aren't propagated to the alias.
+ RemoveHwasanMetadata(proxy);
}
target = proxy;
}
// relocations. A future alternative for this would be finding which usages of
// the vtable can continue to use the untagged hwasan value without any loss of
// value in hwasan.
-void CodeGenVTables::RemoveHwasanMetadata(llvm::GlobalValue *VTable) {
+void CodeGenVTables::RemoveHwasanMetadata(llvm::GlobalValue *GV) const {
if (CGM.getLangOpts().Sanitize.has(SanitizerKind::HWAddress)) {
llvm::GlobalValue::SanitizerMetadata Meta;
- if (VTable->hasSanitizerMetadata())
- Meta = VTable->getSanitizerMetadata();
+ if (GV->hasSanitizerMetadata())
+ Meta = GV->getSanitizerMetadata();
Meta.NoHWAddress = true;
- VTable->setSanitizerMetadata(Meta);
+ GV->setSanitizerMetadata(Meta);
}
}
void GenerateRelativeVTableAlias(llvm::GlobalVariable *VTable,
llvm::StringRef AliasNameRef);
- /// Specify a vtable should not be instrumented with hwasan.
- void RemoveHwasanMetadata(llvm::GlobalValue *VTable);
+ /// Specify a global should not be instrumented with hwasan.
+ void RemoveHwasanMetadata(llvm::GlobalValue *GV) const;
};
} // end namespace CodeGen
/// hwasan-instrumented.
// CHECK-DAG: @_ZTV1A.local = private unnamed_addr constant { [3 x i32] } { [3 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint (ptr @_ZTI1A.rtti_proxy to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @_ZN1A3fooEv to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, no_sanitize_hwaddress, align 4
// CHECK-DAG: @_ZTV1A = unnamed_addr alias { [3 x i32] }, ptr @_ZTV1A.local
+// CHECK-DAG: @_ZTI1A.rtti_proxy = hidden unnamed_addr constant ptr @_ZTI1A, no_sanitize_hwaddress, comdat
class A {
public:
/// If the vtable happens to be hidden, then the alias is not needed. In this
/// case, the original vtable struct itself should be unsanitized.
// CHECK-DAG: @_ZTV1B = hidden unnamed_addr constant { [3 x i32] } { [3 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint (ptr @_ZTI1B.rtti_proxy to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1B, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (ptr dso_local_equivalent @_ZN1B3fooEv to i64), i64 ptrtoint (ptr getelementptr inbounds ({ [3 x i32] }, ptr @_ZTV1B, i32 0, i32 0, i32 2) to i64)) to i32)] }, no_sanitize_hwaddress, align 4
+// CHECK-DAG: @_ZTI1B.rtti_proxy = hidden unnamed_addr constant ptr @_ZTI1B, no_sanitize_hwaddress, comdat
class __attribute__((visibility("hidden"))) B {
public: