1 // dynamic_cast
2 // Ensure that dynamic casting works normally
3
4 // RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -o - -emit-llvm | FileCheck %s
5
6 // CHECK: define{{.*}} ptr @_Z6upcastP1B(ptr noundef readnone returned %b) local_unnamed_addr
7 // CHECK-NEXT: entry:
8 // CHECK-NEXT: ret ptr %b
9 // CHECK-NEXT: }
10
11 // CHECK: define{{.*}} ptr @_Z8downcastP1A(ptr noundef readonly %a) local_unnamed_addr
12 // CHECK-NEXT: entry:
13 // CHECK-NEXT: [[isnull:%[0-9]+]] = icmp eq ptr %a, null
14 // CHECK-NEXT: br i1 [[isnull]], label %[[dynamic_cast_end:[a-z0-9._]+]], label %[[dynamic_cast_notnull:[a-z0-9._]+]]
15 // CHECK: [[dynamic_cast_notnull]]:
16 // CHECK-NEXT: [[as_b:%[0-9]+]] = tail call ptr @__dynamic_cast(ptr nonnull %a, ptr nonnull @_ZTI1A, ptr nonnull @_ZTI1B, i64 0)
17 // CHECK-NEXT: br label %[[dynamic_cast_end]]
18 // CHECK: [[dynamic_cast_end]]:
19 // CHECK-NEXT: [[res:%[0-9]+]] = phi ptr [ [[as_b]], %[[dynamic_cast_notnull]] ], [ null, %entry ]
20 // CHECK-NEXT: ret ptr [[res]]
21 // CHECK-NEXT: }
22
23 // CHECK: declare ptr @__dynamic_cast(ptr, ptr, ptr, i64) local_unnamed_addr
24
25 // CHECK: define{{.*}} ptr @_Z8selfcastP1B(ptr noundef readnone returned %b) local_unnamed_addr
26 // CHECK-NEXT: entry
27 // CHECK-NEXT: ret ptr %b
28 // CHECK-NEXT: }
29
30 // CHECK: define{{.*}} ptr @_Z9void_castP1B(ptr noundef readonly %b) local_unnamed_addr
31 // CHECK-NEXT: entry:
32 // CHECK-NEXT: [[isnull:%[0-9]+]] = icmp eq ptr %b, null
33 // CHECK-NEXT: br i1 [[isnull]], label %[[dynamic_cast_end:[a-z0-9._]+]], label %[[dynamic_cast_notnull:[a-z0-9._]+]]
34 // CHECK: [[dynamic_cast_notnull]]:
35 // CHECK-DAG: [[vtable:%[a-z0-9]+]] = load ptr, ptr %b, align 8
36 // CHECK-DAG: [[offset_ptr:%.+]] = getelementptr inbounds i8, ptr [[vtable]], i64 -8
37 // CHECK-DAG: [[offset_to_top:%.+]] = load i32, ptr [[offset_ptr]], align 4
38 // CHECK-DAG: [[offset_to_top2:%.+]] = sext i32 [[offset_to_top]] to i64
39 // CHECK-DAG: [[casted:%.+]] = getelementptr inbounds i8, ptr %b, i64 [[offset_to_top2]]
40 // CHECK-NEXT: br label %[[dynamic_cast_end]]
41 // CHECK: [[dynamic_cast_end]]:
42 // CHECK-NEXT: [[res:%[0-9]+]] = phi ptr [ [[casted]], %[[dynamic_cast_notnull]] ], [ null, %entry ]
43 // CHECK-NEXT: ret ptr [[res]]
44 // CHECK-NEXT: }
45
46 class A {
47 public:
48 virtual void foo();
49 };
50
51 class B : public A {
52 public:
53 void foo() override;
54 };
55
foo()56 void A::foo() {}
foo()57 void B::foo() {}
58
upcast(B * b)59 A *upcast(B *b) {
60 return dynamic_cast<A *>(b);
61 }
62
downcast(A * a)63 B *downcast(A *a) {
64 return dynamic_cast<B *>(a);
65 }
66
selfcast(B * b)67 B *selfcast(B *b) {
68 return dynamic_cast<B *>(b);
69 }
70
void_cast(B * b)71 void *void_cast(B *b) {
72 return dynamic_cast<void *>(b);
73 }
74