1 // This artificial program allocates and deallocates a lot of large objects
2 // on the stack.  It is a stress test for Memcheck's set_address_range_perms
3 // (sarp) function.  Pretty much all Valgrind versions up to 3.1.X do very
4 // badly on it, ie. a slowdown of at least 100x.
5 //
6 // It is representative of tsim_arch, the simulator for the University of
7 // Texas's TRIPS processor, whose performance under Valgrind is dominated by
8 // the handling of one frequently-called function that allocates 8348 bytes
9 // on the stack.
10 
11 #include <assert.h>
12 #include <time.h>
13 
14 #define REPS   1000*1000*10
15 
16 __attribute__((noinline))
17 int f(int i)
18 {
19    // This nonsense is just to ensure that the compiler does not optimise
20    // away the stack allocation.
21    char big_array[500];
22    big_array[  0] = 12;
23    big_array[ 23] = 34;
24    big_array[256] = 56;
25    big_array[434] = 78;
26    assert( 480 == (&big_array[490] - &big_array[10]) );
27    return big_array[i];
28 }
29 
30 int main(void)
31 {
32    int i, sum = 0;
33 
34    struct timespec req __attribute__((unused));
35    req.tv_sec  = 0;
36    req.tv_nsec = 100*1000*1000;   // 0.1s
37 
38    // Pause for a bit so that the native run-time is not 0.00, which leads
39    // to ridiculous slow-down figures.
40    //nanosleep(&req, NULL);
41 
42    for (i = 0; i < REPS; i++) {
43       sum += f(i & 0xff);
44    }
45    return ( sum == 0xdeadbeef ? 1 : 0 );
46 }
47 
48