Refactored dtor sanitizing into EHScopeStack

Summary:
Dtor sanitization handled amidst other dtor cleanups,
between cleaning bases and fields. Sanitizer call pushed onto
stack of cleanup operations.

Reviewers: eugenis, kcc

Differential Revision: http://reviews.llvm.org/D12022

Refactoring dtor sanitizing emission order.

- Support multiple inheritance by poisoning after
 member destructors are invoked, and before base
 class destructors are invoked.
- Poison for virtual destructor and virtual bases.
- Repress dtor aliasing when sanitizing in dtor.
- CFE test for dtor aliasing, and repression of aliasing in dtor
 code generation.
- Poison members on field-by-field basis, with collective poisoning
 of trivial members when possible.
- Check msan flags and existence of fields, before dtor sanitizing,
 and when determining if aliasing is allowed.
- Testing sanitizing bit fields.

llvm-svn: 246815

1 files changed, 30 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/sanitize-dtor-repress-aliasing.cpp b/clang/test/CodeGenCXX/sanitize-dtor-repress-aliasing.cpp
new file mode 100644
index 00000000000..28624a0e7ae
--- /dev/null
+++ b/clang/test/CodeGenCXX/sanitize-dtor-repress-aliasing.cpp
@@ -0,0 +1,30 @@
+// Test -fsanitize-memory-use-after-dtor
+// RUN: %clang_cc1 -fsanitize=memory -O1 -fsanitize-memory-use-after-dtor -std=c++11 -triple=x86_64-pc-linux -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -fsanitize=memory -O2 -fsanitize-memory-use-after-dtor -std=c++11 -triple=x86_64-pc-linux -emit-llvm -o - %s | FileCheck %s
+
+template <class T>
+class Vector {
+public:
+  int size;
+  ~Vector() {}
+};
+
+// Virtual function table for the derived class only contains
+// its own destructors, with no aliasing to base class dtors.
+struct Base {
+  Vector<int> v;
+  int x;
+  Base() { x = 5; }
+  virtual ~Base() {}
+};
+
+struct Derived : public Base {
+  int z;
+  Derived() { z = 10; }
+  ~Derived() {}
+};
+
+Derived d;
+
+// Definition of virtual function table
+// CHECK: @_ZTV7Derived = {{.*}}@_ZN7DerivedD1Ev{{.*}}@_ZN7DerivedD0Ev