File: cfg-big-switch.c

package info (click to toggle)
llvm-toolchain-6.0 1%3A6.0.1-10
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 598,080 kB
  • sloc: cpp: 3,046,253; ansic: 595,057; asm: 271,965; python: 128,926; objc: 106,554; sh: 21,906; lisp: 10,191; pascal: 6,094; ml: 5,544; perl: 5,265; makefile: 2,227; cs: 2,027; xml: 686; php: 212; csh: 117
file content (27 lines) | stat: -rw-r--r-- 1,438 bytes parent folder | download | duplicates (25)
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
#define EXPAND_2_CASES(i, x, y)    CASE(i, x, y);             CASE(i + 1, x, y);
#define EXPAND_4_CASES(i, x, y)    EXPAND_2_CASES(i, x, y)    EXPAND_2_CASES(i + 2, x, y)
#define EXPAND_8_CASES(i, x, y)    EXPAND_4_CASES(i, x, y)    EXPAND_4_CASES(i + 4, x, y)
#define EXPAND_16_CASES(i, x, y)   EXPAND_8_CASES(i, x, y)    EXPAND_8_CASES(i + 8, x, y)
#define EXPAND_32_CASES(i, x, y)   EXPAND_16_CASES(i, x, y)   EXPAND_16_CASES(i + 16, x, y)
#define EXPAND_64_CASES(i, x, y)   EXPAND_32_CASES(i, x, y)   EXPAND_32_CASES(i + 32, x, y)
#define EXPAND_128_CASES(i, x, y)  EXPAND_64_CASES(i, x, y)   EXPAND_64_CASES(i + 64, x, y)
#define EXPAND_256_CASES(i, x, y)  EXPAND_128_CASES(i, x, y)  EXPAND_128_CASES(i + 128, x, y)
#define EXPAND_512_CASES(i, x, y)  EXPAND_256_CASES(i, x, y)  EXPAND_256_CASES(i + 256, x, y)
#define EXPAND_1024_CASES(i, x, y) EXPAND_512_CASES(i, x, y)  EXPAND_512_CASES(i + 512, x, y)
#define EXPAND_2048_CASES(i, x, y) EXPAND_1024_CASES(i, x, y) EXPAND_1024_CASES(i + 1024, x, y)
#define EXPAND_4096_CASES(i, x, y) EXPAND_2048_CASES(i, x, y) EXPAND_2048_CASES(i + 2048, x, y)

// This has a *monstrous* single fan-out in the CFG, across 8000 blocks inside
// the while loop.
unsigned cfg_big_switch(int x) {
  unsigned y = 0;
  while (x > 0) {
    switch(x) {
#define CASE(i, x, y) \
      case i: { int case_var = 3*x + i; y += case_var - 1; break; }
EXPAND_4096_CASES(0, x, y);
    }
    --x;
  }
  return y;
}