| Oliver Stannard | 3b598b9 | 2019-10-17 09:58:57 +0000 | [diff] [blame^] | 1 | // RUN: %clang_cc1 -triple x86_64-unknown-linux -flto -flto-unit -fvirtual-function-elimination -fwhole-program-vtables -emit-llvm -o - %s | FileCheck %s |
| 2 | |
| 3 | |
| 4 | struct __attribute__((visibility("default"))) A { |
| 5 | virtual void foo(); |
| 6 | }; |
| 7 | |
| 8 | void test_1(A *p) { |
| 9 | // A has default visibility, so no need for type.checked.load. |
| 10 | // CHECK-LABEL: define void @_Z6test_1P1A |
| 11 | // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.A*)*, void (%struct.A*)** {{%.+}}, i64 0 |
| 12 | // CHECK: [[FN_PTR:%.+]] = load void (%struct.A*)*, void (%struct.A*)** [[FN_PTR_ADDR]] |
| 13 | // CHECK: call void [[FN_PTR]]( |
| 14 | p->foo(); |
| 15 | } |
| 16 | |
| 17 | |
| 18 | struct __attribute__((visibility("hidden"))) [[clang::lto_visibility_public]] B { |
| 19 | virtual void foo(); |
| 20 | }; |
| 21 | |
| 22 | void test_2(B *p) { |
| 23 | // B has public LTO visibility, so no need for type.checked.load. |
| 24 | // CHECK-LABEL: define void @_Z6test_2P1B |
| 25 | // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr inbounds void (%struct.B*)*, void (%struct.B*)** {{%.+}}, i64 0 |
| 26 | // CHECK: [[FN_PTR:%.+]] = load void (%struct.B*)*, void (%struct.B*)** [[FN_PTR_ADDR]] |
| 27 | // CHECK: call void [[FN_PTR]]( |
| 28 | p->foo(); |
| 29 | } |
| 30 | |
| 31 | |
| 32 | struct __attribute__((visibility("hidden"))) C { |
| 33 | virtual void foo(); |
| 34 | virtual void bar(); |
| 35 | }; |
| 36 | |
| 37 | void test_3(C *p) { |
| 38 | // C has hidden visibility, so we generate type.checked.load to allow VFE. |
| 39 | // CHECK-LABEL: define void @_Z6test_3P1C |
| 40 | // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 0, metadata !"_ZTS1C") |
| 41 | // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0 |
| 42 | // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)* |
| 43 | // CHECK: call void [[FN_PTR]]( |
| 44 | p->foo(); |
| 45 | } |
| 46 | |
| 47 | void test_4(C *p) { |
| 48 | // When using type.checked.load, we pass the vtable offset to the intrinsic, |
| 49 | // rather than adding it to the pointer with a GEP. |
| 50 | // CHECK-LABEL: define void @_Z6test_4P1C |
| 51 | // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* {{%.+}}, i32 8, metadata !"_ZTS1C") |
| 52 | // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0 |
| 53 | // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)* |
| 54 | // CHECK: call void [[FN_PTR]]( |
| 55 | p->bar(); |
| 56 | } |
| 57 | |
| 58 | void test_5(C *p, void (C::*q)(void)) { |
| 59 | // We also use type.checked.load for the virtual side of member function |
| 60 | // pointer calls. We use a GEP to calculate the address to load from and pass |
| 61 | // 0 as the offset to the intrinsic, because we know that the load must be |
| 62 | // from exactly the point marked by one of the function-type metadatas (in |
| 63 | // this case "_ZTSM1CFvvE.virtual"). If we passed the offset from the member |
| 64 | // function pointer to the intrinsic, this information would be lost. No |
| 65 | // codegen changes on the non-virtual side. |
| 66 | // CHECK-LABEL: define void @_Z6test_5P1CMS_FvvE( |
| 67 | // CHECK: [[FN_PTR_ADDR:%.+]] = getelementptr i8, i8* %vtable, i64 {{%.+}} |
| 68 | // CHECK: [[LOAD:%.+]] = call { i8*, i1 } @llvm.type.checked.load(i8* [[FN_PTR_ADDR]], i32 0, metadata !"_ZTSM1CFvvE.virtual") |
| 69 | // CHECK: [[FN_PTR_I8:%.+]] = extractvalue { i8*, i1 } [[LOAD]], 0 |
| 70 | // CHECK: [[FN_PTR:%.+]] = bitcast i8* [[FN_PTR_I8]] to void (%struct.C*)* |
| 71 | |
| 72 | // CHECK: [[PHI:%.+]] = phi void (%struct.C*)* {{.*}}[ [[FN_PTR]], {{.*}} ] |
| 73 | // CHECK: call void [[PHI]]( |
| 74 | (p->*q)(); |
| 75 | } |