Devirtualize destructor of final class.

Summary:
Take advantage of the final keyword to devirtualize destructor calls.

Fix https://bugs.llvm.org/show_bug.cgi?id=21368

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: davidxl, Prazek, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63161

llvm-svn: 364100

1 files changed, 23 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/devirtualize-dtor-final.cpp b/clang/test/CodeGenCXX/devirtualize-dtor-final.cpp
new file mode 100644
index 00000000000..ea11be773f2
--- /dev/null
+++ b/clang/test/CodeGenCXX/devirtualize-dtor-final.cpp
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple i386-unknown-unknown -std=c++11 %s -emit-llvm -o - | FileCheck %s
+
+namespace Test1 {
+  struct A { virtual ~A() {} };
+  struct B final : A {};
+  struct C : A { virtual ~C() final {} };
+  struct D { virtual ~D() final = 0; };
+  // CHECK-LABEL: define void @_ZN5Test13fooEPNS_1BE
+  void foo(B *b) {
+    // CHECK: call void @_ZN5Test11BD1Ev
+    delete b;
+  }
+  // CHECK-LABEL: define void @_ZN5Test14foo2EPNS_1CE
+  void foo2(C *c) {
+    // CHECK: call void @_ZN5Test11CD1Ev
+    delete c;
+  }
+  // CHECK-LABEL: define void @_ZN5Test14evilEPNS_1DE
+  void evil(D *p) {
+    // CHECK-NOT: call void @_ZN5Test11DD1Ev
+    delete p;
+  }
+}