1 files changed, 44 insertions, 0 deletions
diff --git a/clang/test/CodeGenCXX/tail-padding.cpp b/clang/test/CodeGenCXX/tail-padding.cpp
index b8b9e4ccf9a..afb97a00da7 100644
--- a/clang/test/CodeGenCXX/tail-padding.cpp
+++ b/clang/test/CodeGenCXX/tail-padding.cpp
@@ -32,3 +32,47 @@ namespace InitWithinNVSize {
   // CHECK: store i32 {{.*}} @_ZTVN16InitWithinNVSize1CE
   // CHECK: store i8
 }
+
+namespace NoUniqueAddr {
+  struct A { char c; A(const A&); };
+  struct B { int n; char c[3]; ~B(); };
+  struct C : virtual A { B b; };
+  struct D : virtual A { [[no_unique_address]] B b; };
+  struct E : virtual A { [[no_unique_address]] B b; char x; };
+  static_assert(sizeof(C) == sizeof(void*) + 8 + alignof(void*));
+  static_assert(sizeof(D) == sizeof(void*) + 8);
+  static_assert(sizeof(E) == sizeof(void*) + 8 + alignof(void*));
+
+  // CHECK: define {{.*}} @_ZN12NoUniqueAddr1CC1EOS0_
+  // CHECK: call void @_ZN12NoUniqueAddr1AC2ERKS0_(
+  // CHECK: store i32 {{.*}} @_ZTVN12NoUniqueAddr1CE
+  // Copy the full size of B.
+  // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* {{.*}}, i8* {{.*}}, i64 8, i1 false)
+  C f(C c) { return c; }
+
+  // CHECK: define {{.*}} @_ZN12NoUniqueAddr1DC1EOS0_
+  // CHECK: call void @_ZN12NoUniqueAddr1AC2ERKS0_(
+  // CHECK: store i32 {{.*}} @_ZTVN12NoUniqueAddr1DE
+  // Copy just the data size of B, to avoid overwriting the A base class.
+  // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* {{.*}}, i8* {{.*}}, i64 7, i1 false)
+  D f(D d) { return d; }
+
+  // CHECK: define {{.*}} @_ZN12NoUniqueAddr1EC1EOS0_
+  // CHECK: call void @_ZN12NoUniqueAddr1AC2ERKS0_(
+  // CHECK: store i32 {{.*}} @_ZTVN12NoUniqueAddr1EE
+  // We can copy the full size of B here. (As it happens, we fold the copy of 'x' into
+  // this memcpy, so we're copying 8 bytes either way.)
+  // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* {{.*}}, i8* {{.*}}, i64 8, i1 false)
+  E f(E e) { return e; }
+
+  struct F : virtual A {
+    F(const F &o) : A(o), b(o.b) {}
+    [[no_unique_address]] B b;
+  };
+
+  // CHECK: define {{.*}} @_ZN12NoUniqueAddr1FC1ERKS0_
+  // CHECK: call void @_ZN12NoUniqueAddr1AC2ERKS0_(
+  // CHECK: store i32 {{.*}} @_ZTVN12NoUniqueAddr1FE
+  // CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* {{.*}}, i8* {{.*}}, i64 7, i1 false)
+  F f(F x) { return x; }
+}