Prevent devirtualization of calls to un-instantiated functions.

PR 27895

Differential Revision: https://reviews.llvm.org/D22057


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@305862 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 59 insertions, 0 deletions

diff --git a/test/CodeGen/no-devirt.cpp b/test/CodeGen/no-devirt.cpp
new file mode 100644
index 0000000000..4333b7cde7
--- /dev/null
+++ b/test/CodeGen/no-devirt.cpp
@@ -0,0 +1,59 @@
+// RUN: %clang_cc1 %s -DUSEIT -triple %itanium_abi_triple -emit-llvm -o - |  FileCheck %s
+
+// Test with decls and template defs in pch, and just use in .cpp
+// RUN:  %clang_cc1 %s -DTMPL_DEF_IN_HEADER -triple %itanium_abi_triple -emit-pch -o %t
+// RUN:  %clang_cc1 %s -DTMPL_DEF_IN_HEADER -DUSEIT -triple %itanium_abi_triple -include-pch %t -emit-llvm -o - | FileCheck %s
+
+// Test with A in pch, and B and C in main
+// Test with just decls in pch, and template defs and use in .cpp
+// RUN:  %clang_cc1 %s -triple %itanium_abi_triple -emit-pch -o %t
+// RUN:  %clang_cc1 %s -DUSEIT -triple %itanium_abi_triple -include-pch %t -emit-llvm -o - | FileCheck %s
+
+#ifndef HEADER
+#define HEADER
+template < typename T, int N = 0 > class TmplWithArray {
+public:
+  virtual T& operator [] (int idx);
+  virtual T& func1 (int idx);
+  virtual T& func2 (int idx);
+  T ar[N+1];
+};
+struct Wrapper {
+  TmplWithArray<bool, 10> data;
+  bool indexIt(int a) {
+    if (a > 6) return data[a] ;      // Should not devirtualize
+    if (a > 4) return data.func1(a); // Should devirtualize
+    return data.func2(a);            // Should devirtualize
+  }
+};
+
+#ifdef TMPL_DEF_IN_HEADER
+template <typename T, int N> T& TmplWithArray<T, N >::operator[](int idx) {
+  return ar[idx];
+}
+template <typename T, int N> T& TmplWithArray<T, N >::func1(int idx) {
+  return ar[idx];
+}
+#endif // TMPL_DEF_IN_HEADER
+#endif // HEADER
+
+#ifdef USEIT
+#ifndef TMPL_DEF_IN_HEADER
+template <typename T, int N> T& TmplWithArray<T, N >::operator[](int idx) {
+  return ar[idx];
+}
+template <typename T, int N> T& TmplWithArray<T, N >::func1(int idx) {
+  return ar[idx];
+}
+#endif // !TMPL_DEF_IN_HEADER
+extern Wrapper ew;
+bool stuff(int p)
+{
+  return ew.indexIt(p);
+}
+#endif
+
+// CHECK-NOT: call {{.*}} @_ZN13TmplWithArrayIbLi10EEixEi
+// CHECK-DAG: call {{.*}} @_ZN13TmplWithArrayIbLi10EE5func1Ei
+// CHECK-DAG: call {{.*}} @_ZN13TmplWithArrayIbLi10EE5func2Ei
+