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.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@246815 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 82 insertions, 0 deletions

diff --git a/test/CodeGenCXX/sanitize-dtor-nontrivial-virtual-base.cpp b/test/CodeGenCXX/sanitize-dtor-nontrivial-virtual-base.cpp
new file mode 100644
index 0000000000..27eb64b553
--- /dev/null
+++ b/test/CodeGenCXX/sanitize-dtor-nontrivial-virtual-base.cpp
@@ -0,0 +1,82 @@
+// RUN: %clang_cc1 -fsanitize=memory -O0 -fsanitize-memory-use-after-dtor -std=c++11 -triple=x86_64-pc-linux -emit-llvm -o - %s | FileCheck %s
+// 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
+
+template <class T>
+class Vector {
+public:
+  int size;
+  ~Vector() {
+    size += 1;
+  }
+};
+
+struct Base {
+  int b1;
+  double b2;
+  Base() {
+    b1 = 5;
+    b2 = 10.989;
+  }
+  virtual ~Base() {}
+};
+
+struct VirtualBase {
+  int vb1;
+  int vb2;
+  VirtualBase() {
+    vb1 = 10;
+    vb2 = 11;
+  }
+  virtual ~VirtualBase() {}
+};
+
+struct Derived : public Base, public virtual VirtualBase {
+  int d1;
+  Vector<int> v;
+  int d2;
+  Derived() {
+    d1 = 10;
+  }
+  ~Derived() {}
+};
+
+Derived d;
+
+// Destruction order:
+// Derived: int, Vector, Base, VirtualBase
+
+// CHECK-LABEL: define {{.*}}ZN7DerivedD1Ev
+// CHECK: call void {{.*}}ZN11VirtualBaseD2Ev
+// CHECK: ret void
+
+// CHECK-LABEL: define {{.*}}ZN7DerivedD0Ev
+// CHECK: ret void
+
+// CHECK-LABEL: define {{.*}}ZN11VirtualBaseD1Ev
+// CHECK: ret void
+
+// CHECK-LABEL: define {{.*}}ZN11VirtualBaseD0Ev
+// CHECK: ret void
+
+// poison 2 ints
+// CHECK-LABEL: define {{.*}}ZN11VirtualBaseD2Ev
+// CHECK: call void {{.*}}sanitizer_dtor_callback({{.*}}, i64 8)
+// CHECK: ret void
+
+// poison int and double
+// CHECK-LABEL: define {{.*}}ZN4BaseD2Ev
+// CHECK: call void {{.*}}sanitizer_dtor_callback({{.*}}, i64 16)
+// CHECK: ret void
+
+// poison int, ignore vector, poison int
+// CHECK-LABEL: define {{.*}}ZN7DerivedD2Ev
+// CHECK: call void {{.*}}ZN6VectorIiED1Ev
+// CHECK: call void {{.*}}sanitizer_dtor_callback({{.*}}, i64 4)
+// CHECK: call void {{.*}}sanitizer_dtor_callback({{.*}}, i64 4)
+// CHECK: call void {{.*}}ZN4BaseD2Ev
+// CHECK: ret void
+
+// poison int
+// CHECK-LABEL: define {{.*}}ZN6VectorIiED2Ev
+// CHECK: call void {{.*}}sanitizer_dtor_callback({{.*}}, i64 4)
+// CHECK: ret void