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// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O2 | FileCheck %s
// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O0 | FileCheck --check-prefix=O0 %s
int a = 42;
inline int bcp(int x) {
return __builtin_constant_p(x);
}
/* --- Compound literals */
struct foo { int x, y; };
int y;
struct foo f = (struct foo){ __builtin_constant_p(y), 42 };
struct foo test0(int expr) {
// CHECK: define i64 @test0(i32 %expr)
// CHECK: call i1 @llvm.is.constant.i32(i32 %expr)
struct foo f = (struct foo){ __builtin_constant_p(expr), 42 };
return f;
}
/* --- Pointer types */
inline int test1_i(int *x) {
return *x;
}
int test1() {
// CHECK: define i32 @test1
// CHECK: add nsw i32 %0, -13
// CHECK-NEXT: call i1 @llvm.is.constant.i32(i32 %sub)
return bcp(test1_i(&a) - 13);
}
int test2() {
// CHECK: define i32 @test2
// CHECK: ret i32 0
return __builtin_constant_p(&a - 13);
}
inline int test3_i(int *x) {
return 42;
}
int test3() {
// CHECK: define i32 @test3
// CHECK: ret i32 1
return bcp(test3_i(&a) - 13);
}
/* --- Aggregate types */
int b[] = {1, 2, 3};
int test4() {
// CHECK: define i32 @test4
// CHECK: ret i32 0
return __builtin_constant_p(b);
}
const char test5_c[] = {1, 2, 3, 0};
int test5() {
// CHECK: define i32 @test5
// CHECK: ret i32 0
return __builtin_constant_p(test5_c);
}
inline char test6_i(const char *x) {
return x[1];
}
int test6() {
// CHECK: define i32 @test6
// CHECK: ret i32 0
return __builtin_constant_p(test6_i(test5_c));
}
/* --- Non-constant global variables */
int test7() {
// CHECK: define i32 @test7
// CHECK: call i1 @llvm.is.constant.i32(i32 %0)
return bcp(a);
}
/* --- Constant global variables */
const int c = 42;
int test8() {
// CHECK: define i32 @test8
// CHECK: ret i32 1
return bcp(c);
}
/* --- Array types */
int arr[] = { 1, 2, 3 };
const int c_arr[] = { 1, 2, 3 };
int test9() {
// CHECK: define i32 @test9
// CHECK: call i1 @llvm.is.constant.i32(i32 %0)
return __builtin_constant_p(arr[2]);
}
int test10() {
// CHECK: define i32 @test10
// CHECK: ret i32 1
return __builtin_constant_p(c_arr[2]);
}
int test11() {
// CHECK: define i32 @test11
// CHECK: ret i32 0
return __builtin_constant_p(c_arr);
}
/* --- Function pointers */
int test12() {
// CHECK: define i32 @test12
// CHECK: ret i32 0
return __builtin_constant_p(&test10);
}
int test13() {
// CHECK: define i32 @test13
// CHECK: ret i32 1
return __builtin_constant_p(&test10 != 0);
}
typedef unsigned long uintptr_t;
#define assign(p, v) ({ \
uintptr_t _r_a_p__v = (uintptr_t)(v); \
if (__builtin_constant_p(v) && _r_a_p__v == (uintptr_t)0) { \
union { \
uintptr_t __val; \
char __c[1]; \
} __u = { \
.__val = (uintptr_t)_r_a_p__v \
}; \
*(volatile unsigned int*)&p = *(unsigned int*)(__u.__c); \
__u.__val; \
} \
_r_a_p__v; \
})
typedef void fn_p(void);
extern fn_p *dest_p;
static void src_fn(void) {
}
void test14() {
assign(dest_p, src_fn);
}
extern int test15_v;
struct { const char *t; int a; } test15[] = {
{ "tag", __builtin_constant_p(test15_v) && !test15_v ? 1 : 0 }
};
extern char test16_v;
struct { int a; } test16 = { __builtin_constant_p(test16_v) };
extern unsigned long long test17_v;
void test17() {
// O0: define void @test17
// O0: call void asm sideeffect "", {{.*}}(i32 -1)
// CHECK: define void @test17
// CHECK: call void asm sideeffect "", {{.*}}(i32 -1)
__asm__ __volatile__("" :: "n"( (__builtin_constant_p(test17_v) || 0) ? 1 : -1));
}
int test18_f();
// CHECK: define void @test18
// CHECK-NOT: call {{.*}}test18_f
void test18() {
int a, b;
(void)__builtin_constant_p((a = b, test18_f()));
}
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