1 /* Source for debugging optimimzed code test.
2
3 cc -g -O -o optimize optimize.c
4 */
5 int callee();
6 int test_opt;
7
main()8 int main()
9 {
10 int a,b,c,d,e,f,g,h;
11
12 a = 10;;
13
14 /* Value propagate
15 */
16 b = 2 * a + 1;
17 c = 3 * b + 2;
18
19 /* Re-use expressions
20 */
21 d = (2 * a + 1) * (3 * b + 2);
22 e = (2 * a + 1) * (3 * b + 2);
23
24 /* Create dead stores--do lines still exist?
25 */
26 d = (2 * a + 1) * (3 * b + 2);
27 e = (2 * a + 1) * (3 * b + 2);
28 d = (2 * a + 1) * (3 * b + 2);
29 e = (2 * a + 1) * (3 * b + 2);
30
31 /* Alpha and psi motion
32 */
33 if( test_opt ) {
34 f = e - d;
35 f = f--;
36 }
37 else {
38 f = e - d;
39 f = f + d * e;
40 }
41
42 /* Chi and Rho motion
43 */
44 h = 0;
45 do {
46 h++;
47 a = b * c + d * e; /* Chi */
48 f = f + d * e;
49 g = f + d * e; /* Rho */
50 callee( g+1 );
51 test_opt = (test_opt != 1); /* Cycles */
52 } while( g && h < 10);
53
54 /* Opps for tail recursion, unrolling,
55 * folding, evaporating
56 */
57 for( a = 0; a < 100; a++ ) {
58 callee( callee ( callee( a )));
59 callee( callee ( callee( a )));
60 callee( callee ( callee( a )));
61 }
62
63 return callee( test_opt );
64 }
65
66 /* defined late to keep line numbers the same
67 */
callee(x)68 int callee( x )
69 int x; /* not used! */
70 {
71 test_opt++; /* side effect */
72
73 return test_opt;
74 }
75
76 /* end */