builtin-constant-p.cpp
1.03 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
// RUN: %clang_cc1 -triple=x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
// Don't crash if the argument to __builtin_constant_p isn't scalar.
template <typename T>
constexpr bool is_constant(const T v) {
return __builtin_constant_p(v);
}
template <typename T>
class numeric {
public:
using type = T;
template <typename S>
constexpr numeric(S value)
: value_(static_cast<T>(value)) {}
private:
const T value_;
};
bool bcp() {
return is_constant(numeric<int>(1));
}
// PR45535
struct with_dtor {
~with_dtor();
};
// CHECK: define {{.*}}bcp_stmt_expr_1
bool bcp_stmt_expr_1() {
// CHECK-NOT: call {{.*}}with_dtorD
return __builtin_constant_p(({with_dtor wd; 123;}));
}
int do_not_call();
// CHECK: define {{.*}}bcp_stmt_expr_2
bool bcp_stmt_expr_2(int n) {
// CHECK-NOT: call {{.*}}do_not_call
return __builtin_constant_p(({
// This has a side-effect due to the VLA bound, so CodeGen should fold it
// to false.
typedef int arr[do_not_call()];
n;
}));
// CHECK-NOT: }
// CHECK: ret i1 false
}