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
