C++1y: Allow aggregates to have default initializers.

Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.

There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179958 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 74 insertions, 0 deletions

diff --git a/test/CodeGenCXX/cxx1y-initializer-aggregate.cpp b/test/CodeGenCXX/cxx1y-initializer-aggregate.cpp
new file mode 100644
index 0000000000..ef78c434e3
--- /dev/null
+++ b/test/CodeGenCXX/cxx1y-initializer-aggregate.cpp
@@ -0,0 +1,74 @@
+// RUN: %clang_cc1 -std=c++1y %s -triple x86_64-linux-gnu -emit-llvm -o - | FileCheck %s
+
+struct A {
+  int n = 0;
+  const char *p;
+  char k = p[n];
+  int f();
+  int x = f();
+  union {
+    char c;
+    double d = 1.0;
+  };
+};
+
+int f();
+
+union B {
+  int a;
+  int f();
+  int b = f();
+};
+
+A a { .p = "foobar" };
+A b { 4, "bazquux", .x = 42, .c = 9 };
+A c { 1, 0, 'A', f(), { 3 } };
+
+// CHECK: @[[STR_A:.*]] = {{.*}} [7 x i8] c"foobar\00"
+// CHECK: @[[STR_B:.*]] = {{.*}} [8 x i8] c"bazquux\00"
+
+B x;
+B y {};
+B z { 1 };
+// CHECK: @z = global {{.*}} { i32 1 }
+
+// Initialization of 'a':
+
+// CHECK: store i32 0, i32* getelementptr inbounds ({{.*}} @a, i32 0, i32 0)
+// CHECK: store i8* {{.*}} @[[STR_A]]{{.*}}, i8** getelementptr inbounds ({{.*}} @a, i32 0, i32 1)
+// CHECK: load i32* getelementptr inbounds ({{.*}} @a, i32 0, i32 0)
+// CHECK: load i8** getelementptr inbounds ({{.*}} @a, i32 0, i32 1)
+// CHECK: getelementptr inbounds i8* %{{.*}}, {{.*}} %{{.*}}
+// CHECK: store i8 %{{.*}}, i8* getelementptr inbounds ({{.*}} @a, i32 0, i32 2)
+// CHECK: call i32 @_ZN1A1fEv({{.*}} @a)
+// CHECK: store i32 %{{.*}}, i32* getelementptr inbounds ({{.*}}* @a, i32 0, i32 3)
+// CHECK: call void @{{.*}}C1Ev({{.*}} getelementptr inbounds (%struct.A* @a, i32 0, i32 4))
+
+// Initialization of 'b':
+
+// CHECK: store i32 4, i32* getelementptr inbounds ({{.*}} @b, i32 0, i32 0)
+// CHECK: store i8* {{.*}} @[[STR_B]]{{.*}}, i8** getelementptr inbounds ({{.*}} @b, i32 0, i32 1)
+// CHECK: load i32* getelementptr inbounds ({{.*}} @b, i32 0, i32 0)
+// CHECK: load i8** getelementptr inbounds ({{.*}} @b, i32 0, i32 1)
+// CHECK: getelementptr inbounds i8* %{{.*}}, {{.*}} %{{.*}}
+// CHECK: store i8 %{{.*}}, i8* getelementptr inbounds ({{.*}} @b, i32 0, i32 2)
+// CHECK-NOT: @_ZN1A1fEv
+// CHECK: store i32 42, i32* getelementptr inbounds ({{.*}}* @b, i32 0, i32 3)
+// CHECK-NOT: C1Ev
+// CHECK: store i8 9, i8* {{.*}} @b, i32 0, i32 4)
+
+// Initialization of 'c':
+
+// CHECK: store i32 1, i32* getelementptr inbounds ({{.*}} @c, i32 0, i32 0)
+// CHECK: store i8* null, i8** getelementptr inbounds ({{.*}} @c, i32 0, i32 1)
+// CHECK-NOT: load
+// CHECK: store i8 65, i8* getelementptr inbounds ({{.*}} @c, i32 0, i32 2)
+// CHECK: call i32 @_Z1fv()
+// CHECK: store i32 %{{.*}}, i32* getelementptr inbounds ({{.*}}* @c, i32 0, i32 3)
+// CHECK-NOT: C1Ev
+// CHECK: store i8 3, i8* {{.*}} @c, i32 0, i32 4)
+
+// CHECK: call void @_ZN1BC1Ev({{.*}} @x)
+
+// CHECK: call i32 @_ZN1B1fEv({{.*}} @y)
+// CHECK: store i32 %{{.*}}, i32* getelementptr inbounds ({{.*}} @y, i32 0, i32 0)