1 // RUN: %clang_cc1 -emit-llvm -O1 -o - %s | FileCheck %s
2 // RUN: %clang_cc1 -emit-llvm -O1 -fcxx-exceptions -fexceptions -o - %s | FileCheck --check-prefix=CHECK-EH %s
3
4 // Test code generation for the named return value optimization.
5 class X {
6 public:
7 X();
8 X(const X&);
9 ~X();
10 };
11
12 // CHECK: define void @_Z5test0v
13 // CHECK-EH: define void @_Z5test0v
test0()14 X test0() {
15 X x;
16 // CHECK: call {{.*}} @_ZN1XC1Ev
17 // CHECK-NEXT: ret void
18
19 // CHECK-EH: call {{.*}} @_ZN1XC1Ev
20 // CHECK-EH-NEXT: ret void
21 return x;
22 }
23
24 // CHECK: define void @_Z5test1b(
25 // CHECK-EH: define void @_Z5test1b(
test1(bool B)26 X test1(bool B) {
27 // CHECK: tail call {{.*}} @_ZN1XC1Ev
28 // CHECK-NEXT: ret void
29 X x;
30 if (B)
31 return (x);
32 return x;
33 // CHECK-EH: tail call {{.*}} @_ZN1XC1Ev
34 // CHECK-EH-NEXT: ret void
35 }
36
37 // CHECK: define void @_Z5test2b
38 // CHECK-EH: define void @_Z5test2b
test2(bool B)39 X test2(bool B) {
40 // No NRVO.
41
42 X x;
43 X y;
44 if (B)
45 return y;
46 return x;
47
48 // CHECK: call {{.*}} @_ZN1XC1Ev
49 // CHECK-NEXT: call {{.*}} @_ZN1XC1Ev
50 // CHECK: call {{.*}} @_ZN1XC1ERKS_
51 // CHECK: call {{.*}} @_ZN1XC1ERKS_
52 // CHECK: call {{.*}} @_ZN1XD1Ev
53 // CHECK: call {{.*}} @_ZN1XD1Ev
54 // CHECK: ret void
55
56 // The block ordering in the -fexceptions IR is unfortunate.
57
58 // CHECK-EH: call {{.*}} @_ZN1XC1Ev
59 // CHECK-EH-NEXT: invoke {{.*}} @_ZN1XC1Ev
60 // -> %invoke.cont, %lpad
61
62 // %invoke.cont:
63 // CHECK-EH: br i1
64 // -> %if.then, %if.end
65
66 // %if.then: returning 'x'
67 // CHECK-EH: invoke {{.*}} @_ZN1XC1ERKS_
68 // -> %cleanup, %lpad1
69
70 // %lpad: landing pad for ctor of 'y', dtor of 'y'
71 // CHECK-EH: call i8* @llvm.eh.exception()
72 // CHECK-EH: call i32 (i8*, i8*, ...)* @llvm.eh.selector
73 // CHECK-EH-NEXT: br label
74 // -> %eh.cleanup
75
76 // %lpad1: landing pad for return copy ctors, EH cleanup for 'y'
77 // CHECK-EH: invoke {{.*}} @_ZN1XD1Ev
78 // -> %eh.cleanup, %terminate.lpad
79
80 // %if.end: returning 'y'
81 // CHECK-EH: invoke {{.*}} @_ZN1XC1ERKS_
82 // -> %cleanup, %lpad1
83
84 // %cleanup: normal cleanup for 'y'
85 // CHECK-EH: invoke {{.*}} @_ZN1XD1Ev
86 // -> %invoke.cont11, %lpad
87
88 // %invoke.cont11: normal cleanup for 'x'
89 // CHECK-EH: call {{.*}} @_ZN1XD1Ev
90 // CHECK-EH-NEXT: ret void
91
92 // %eh.cleanup: EH cleanup for 'x'
93 // CHECK-EH: invoke {{.*}} @_ZN1XD1Ev
94 // -> %invoke.cont17, %terminate.lpad
95
96 // %invoke.cont17: rethrow block for %eh.cleanup.
97 // This really should be elsewhere in the function.
98 // CHECK-EH: call void @llvm.eh.resume(
99 // CHECK-EH-NEXT: unreachable
100
101 // %terminate.lpad: terminate landing pad.
102 // CHECK-EH: call i8* @llvm.eh.exception()
103 // CHECK-EH-NEXT: call i32 (i8*, i8*, ...)* @llvm.eh.selector
104 // CHECK-EH-NEXT: call void @_ZSt9terminatev()
105 // CHECK-EH-NEXT: unreachable
106
107 }
108
test3(bool B)109 X test3(bool B) {
110 // FIXME: We don't manage to apply NRVO here, although we could.
111 {
112 X y;
113 return y;
114 }
115 X x;
116 return x;
117 }
118
119 extern "C" void exit(int) throw();
120
121 // CHECK: define void @_Z5test4b
test4(bool B)122 X test4(bool B) {
123 {
124 // CHECK: tail call {{.*}} @_ZN1XC1Ev
125 X x;
126 // CHECK: br i1
127 if (B)
128 return x;
129 }
130 // CHECK: tail call {{.*}} @_ZN1XD1Ev
131 // CHECK: tail call void @exit(i32 1)
132 exit(1);
133 }
134
135 #ifdef __EXCEPTIONS
136 // CHECK-EH: define void @_Z5test5
137 void may_throw();
test5()138 X test5() {
139 try {
140 may_throw();
141 } catch (X x) {
142 // CHECK-EH: invoke {{.*}} @_ZN1XC1ERKS_
143 // CHECK-EH: call void @__cxa_end_catch()
144 // CHECK-EH: ret void
145 return x;
146 }
147 }
148 #endif
149