1*67e74705SXin Li // Hammer the CFG with large numbers of overlapping variable scopes, which
2*67e74705SXin Li // implicit destructors triggered at each edge.
3*67e74705SXin Li
4*67e74705SXin Li #define EXPAND_BASIC_STRUCT(i) struct X##i { X##i(int); ~X##i(); };
5*67e74705SXin Li #define EXPAND_NORET_STRUCT(i) struct X##i { X##i(int); ~X##i() __attribute__((noreturn)); };
6*67e74705SXin Li EXPAND_BASIC_STRUCT(0000); EXPAND_NORET_STRUCT(0001);
7*67e74705SXin Li EXPAND_BASIC_STRUCT(0010); EXPAND_BASIC_STRUCT(0011);
8*67e74705SXin Li EXPAND_BASIC_STRUCT(0100); EXPAND_NORET_STRUCT(0101);
9*67e74705SXin Li EXPAND_NORET_STRUCT(0110); EXPAND_BASIC_STRUCT(0111);
10*67e74705SXin Li EXPAND_BASIC_STRUCT(1000); EXPAND_NORET_STRUCT(1001);
11*67e74705SXin Li EXPAND_BASIC_STRUCT(1010); EXPAND_BASIC_STRUCT(1011);
12*67e74705SXin Li EXPAND_NORET_STRUCT(1100); EXPAND_NORET_STRUCT(1101);
13*67e74705SXin Li EXPAND_BASIC_STRUCT(1110); EXPAND_BASIC_STRUCT(1111);
14*67e74705SXin Li
15*67e74705SXin Li #define EXPAND_2_VARS(c, i, x) const X##i var_##c##_##i##0(x), &var_##c##_##i##1 = X##i(x)
16*67e74705SXin Li #define EXPAND_4_VARS(c, i, x) EXPAND_2_VARS(c, i##0, x); EXPAND_2_VARS(c, i##1, x)
17*67e74705SXin Li #define EXPAND_8_VARS(c, i, x) EXPAND_4_VARS(c, i##0, x); EXPAND_4_VARS(c, i##1, x)
18*67e74705SXin Li #define EXPAND_16_VARS(c, i, x) EXPAND_8_VARS(c, i##0, x); EXPAND_8_VARS(c, i##1, x)
19*67e74705SXin Li #define EXPAND_32_VARS(c, x) EXPAND_16_VARS(c, 0, x); EXPAND_16_VARS(c, 1, x)
20*67e74705SXin Li
21*67e74705SXin Li #define EXPAND_2_INNER_CASES(i, x, y) INNER_CASE(i, x, y); INNER_CASE(i + 1, x, y);
22*67e74705SXin Li #define EXPAND_4_INNER_CASES(i, x, y) EXPAND_2_INNER_CASES(i, x, y) EXPAND_2_INNER_CASES(i + 2, x, y)
23*67e74705SXin Li #define EXPAND_8_INNER_CASES(i, x, y) EXPAND_4_INNER_CASES(i, x, y) EXPAND_4_INNER_CASES(i + 4, x, y)
24*67e74705SXin Li #define EXPAND_16_INNER_CASES(i, x, y) EXPAND_8_INNER_CASES(i, x, y) EXPAND_8_INNER_CASES(i + 8, x, y)
25*67e74705SXin Li #define EXPAND_32_INNER_CASES(i, x, y) EXPAND_16_INNER_CASES(i, x, y) EXPAND_16_INNER_CASES(i + 16, x, y)
26*67e74705SXin Li
27*67e74705SXin Li #define EXPAND_2_OUTER_CASES(i, x, y) OUTER_CASE(i, x, y); OUTER_CASE(i + 1, x, y);
28*67e74705SXin Li #define EXPAND_4_OUTER_CASES(i, x, y) EXPAND_2_OUTER_CASES(i, x, y) EXPAND_2_OUTER_CASES(i + 2, x, y)
29*67e74705SXin Li #define EXPAND_8_OUTER_CASES(i, x, y) EXPAND_4_OUTER_CASES(i, x, y) EXPAND_4_OUTER_CASES(i + 4, x, y)
30*67e74705SXin Li #define EXPAND_16_OUTER_CASES(i, x, y) EXPAND_8_OUTER_CASES(i, x, y) EXPAND_8_OUTER_CASES(i + 8, x, y)
31*67e74705SXin Li #define EXPAND_32_OUTER_CASES(i, x, y) EXPAND_16_OUTER_CASES(i, x, y) EXPAND_16_OUTER_CASES(i + 16, x, y)
32*67e74705SXin Li
cfg_nested_vars(int x)33*67e74705SXin Li unsigned cfg_nested_vars(int x) {
34*67e74705SXin Li int y = 0;
35*67e74705SXin Li while (x > 0) {
36*67e74705SXin Li EXPAND_32_VARS(a, x);
37*67e74705SXin Li switch (x) {
38*67e74705SXin Li #define INNER_CASE(i, x, y) \
39*67e74705SXin Li case i: { \
40*67e74705SXin Li int case_var = 3*x + i; \
41*67e74705SXin Li EXPAND_32_VARS(c, case_var); \
42*67e74705SXin Li y += case_var - 1; \
43*67e74705SXin Li break; \
44*67e74705SXin Li }
45*67e74705SXin Li #define OUTER_CASE(i, x, y) \
46*67e74705SXin Li case i: { \
47*67e74705SXin Li int case_var = y >> 8; \
48*67e74705SXin Li EXPAND_32_VARS(b, y); \
49*67e74705SXin Li switch (case_var) { \
50*67e74705SXin Li EXPAND_32_INNER_CASES(0, x, y); \
51*67e74705SXin Li } \
52*67e74705SXin Li break; \
53*67e74705SXin Li }
54*67e74705SXin Li EXPAND_32_OUTER_CASES(0, x, y);
55*67e74705SXin Li }
56*67e74705SXin Li --x;
57*67e74705SXin Li }
58*67e74705SXin Li return y;
59*67e74705SXin Li }
60