[OpenCL] Improve destructor support in C++ for OpenCL

This re-applies r366422 with a fix for Bug PR42665 and a new regression
test.

llvm-svn: 366670

1 files changed, 61 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/PR42665.cpp b/clang/test/CodeGenCXX/PR42665.cpp
new file mode 100644
index 00000000000..4a460cfa107
--- /dev/null
+++ b/clang/test/CodeGenCXX/PR42665.cpp
@@ -0,0 +1,61 @@
+// RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -std=c++17 -O0 %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple %ms_abi_triple -emit-llvm -std=c++17 -O0 %s -o - | FileCheck %s
+
+// Minimal reproducer for PR42665.
+
+struct Foo {
+  Foo() = default;
+  virtual ~Foo() = default;
+};
+
+template <typename Deleter>
+struct Pair {
+  Foo first;
+  Deleter second;
+};
+
+template <typename Deleter>
+Pair(Foo, Deleter) -> Pair<Deleter>;
+
+template <typename T>
+void deleter(T& t) { t.~T(); }
+
+auto make_pair() {
+  return Pair{ Foo(), deleter<Foo> };
+}
+
+void foobar() {
+  auto p = make_pair();
+  auto& f = p.first;
+  auto& d = p.second;
+  d(f); // Invoke virtual destructor of Foo through d.
+} // p's destructor is invoked.
+
+// Regexes are used to handle both kind of mangling.
+//
+// CHECK-LABEL: define linkonce_odr{{( dso_local)?}} void @{{.*deleter.*Foo.*}}(%struct.Foo* dereferenceable({{[0-9]+}})
+// CHECK-SAME: [[T:%.*]])
+// CHECK: [[T_ADDR:%.*]] = alloca %struct.Foo*
+// CHECK: store %struct.Foo* [[T]], %struct.Foo** [[T_ADDR]]
+// CHECK: [[R0:%.*]] = load %struct.Foo*, %struct.Foo** [[T_ADDR]]
+// CHECK: [[R1:%.*]] = bitcast %struct.Foo* [[R0]] to [[TYPE:.*struct\.Foo.*]]***
+// CHECK: [[VTABLE:%.*]] = load [[TYPE]]**, [[TYPE]]*** [[R1]]
+// CHECK: [[VFUN:%.*]] = getelementptr inbounds [[TYPE]]*, [[TYPE]]** [[VTABLE]], i64 0
+// CHECK: [[DTOR:%.*]] = load [[TYPE]]*, [[TYPE]]** [[VFUN]]
+// CHECK: call {{(void|i8\*)}} [[DTOR]](%struct.Foo* [[R0]]
+//
+// CHECK-LABEL: define{{( dso_local)?}} void @{{.*foobar.*}}()
+// CHECK: [[P:%.*]] = alloca %struct.Pair
+// CHECK: [[F:%.*]] = alloca %struct.Foo*
+// CHECK: [[D:%.*]] = alloca [[TYPE:void \(%struct.Foo\*\)]]**
+// CHECK: call void @{{.*make_pair.*}}(%struct.Pair* sret [[P]])
+// CHECK: [[FIRST:%.*]] = getelementptr inbounds %struct.Pair, %struct.Pair* [[P]], i32 0, i32 0
+// CHECK: store %struct.Foo* [[FIRST]], %struct.Foo** [[F]]
+// CHECK: [[SECOND:%.*]] = getelementptr inbounds %struct.Pair, %struct.Pair* [[P]], i32 0, i32 1
+// CHECK: store void (%struct.Foo*)** [[SECOND]], [[TYPE]]*** [[D]]
+// CHECK: [[R0:%.*]] = load [[TYPE]]**, [[TYPE]]*** [[D]]
+// CHECK: [[R1:%.*]] = load [[TYPE]]*, [[TYPE]]** [[R0]]
+// CHECK: [[R2:%.*]] = load %struct.Foo*, %struct.Foo** [[F]]
+// CHECK: call void [[R1]](%struct.Foo* dereferenceable({{[0-9]+}}) [[R2]])
+// CHECK: call void @{{.*Pair.*Foo.*}}(%struct.Pair* [[P]])
+