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