1 #define EXPAND_2_CASES(i, x, y) CASE(i, x, y); CASE(i + 1, x, y); 2 #define EXPAND_4_CASES(i, x, y) EXPAND_2_CASES(i, x, y) EXPAND_2_CASES(i + 2, x, y) 3 #define EXPAND_8_CASES(i, x, y) EXPAND_4_CASES(i, x, y) EXPAND_4_CASES(i + 4, x, y) 4 #define EXPAND_16_CASES(i, x, y) EXPAND_8_CASES(i, x, y) EXPAND_8_CASES(i + 8, x, y) 5 #define EXPAND_32_CASES(i, x, y) EXPAND_16_CASES(i, x, y) EXPAND_16_CASES(i + 16, x, y) 6 #define EXPAND_64_CASES(i, x, y) EXPAND_32_CASES(i, x, y) EXPAND_32_CASES(i + 32, x, y) 7 #define EXPAND_128_CASES(i, x, y) EXPAND_64_CASES(i, x, y) EXPAND_64_CASES(i + 64, x, y) 8 #define EXPAND_256_CASES(i, x, y) EXPAND_128_CASES(i, x, y) EXPAND_128_CASES(i + 128, x, y) 9 #define EXPAND_512_CASES(i, x, y) EXPAND_256_CASES(i, x, y) EXPAND_256_CASES(i + 256, x, y) 10 #define EXPAND_1024_CASES(i, x, y) EXPAND_512_CASES(i, x, y) EXPAND_512_CASES(i + 512, x, y) 11 #define EXPAND_2048_CASES(i, x, y) EXPAND_1024_CASES(i, x, y) EXPAND_1024_CASES(i + 1024, x, y) 12 #define EXPAND_4096_CASES(i, x, y) EXPAND_2048_CASES(i, x, y) EXPAND_2048_CASES(i + 2048, x, y) 13 14 // This has a *monstrous* single fan-out in the CFG, across 8000 blocks inside 15 // the while loop. 16 unsigned cfg_big_switch(int x) { 17 unsigned y = 0; 18 while (x > 0) { 19 switch(x) { 20 #define CASE(i, x, y) \ 21 case i: { int case_var = 3*x + i; y += case_var - 1; break; } 22 EXPAND_4096_CASES(0, x, y); 23 } 24 --x; 25 } 26 return y; 27 } 28
