PR30937: don't devirtualize if we find that the callee is a pure virtual

function. In that case, there is no requirement that the callee is actually
defined, and the code may in fact be valid and have defined behavior if the
virtual call is unreachable.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@286534 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 34 insertions, 0 deletions

diff --git a/test/CodeGenCXX/devirtualize-virtual-function-calls.cpp b/test/CodeGenCXX/devirtualize-virtual-function-calls.cpp
index f2dc978972..b4c39f3fcf 100644
--- a/test/CodeGenCXX/devirtualize-virtual-function-calls.cpp
+++ b/test/CodeGenCXX/devirtualize-virtual-function-calls.cpp
@@ -161,3 +161,37 @@ namespace test4 {
     p->fish.eat();
   }
 }
+
+// Do not devirtualize to pure virtual function calls.
+namespace test5 {
+  struct X {
+    virtual void f() = 0;
+  };
+  struct Y {};
+  // CHECK-LABEL: define {{.*}} @_ZN5test51f
+  void f(Y &y, X Y::*p) {
+    // CHECK-NOT: call {{.*}} @_ZN5test51X1fEv
+    // CHECK: call void %
+    (y.*p).f();
+  };
+
+  struct Z final {
+    virtual void f() = 0;
+  };
+  // CHECK-LABEL: define {{.*}} @_ZN5test51g
+  void g(Z &z) {
+    // CHECK-NOT: call {{.*}} @_ZN5test51Z1fEv
+    // CHECK: call void %
+    z.f();
+  }
+
+  struct Q {
+    virtual void f() final = 0;
+  };
+  // CHECK-LABEL: define {{.*}} @_ZN5test51h
+  void h(Q &q) {
+    // CHECK-NOT: call {{.*}} @_ZN5test51Q1fEv
+    // CHECK: call void %
+    q.f();
+  }
+}