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))
17int 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
30int 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