compiler-rt/test/profile/Inputs/instrprof-gcov-parallel.driver.c

   1 #include <stdatomic.h>
   2 #include <stdlib.h>
   3 #include <sys/mman.h>
   4 #include <sys/types.h>
   5 #include <sys/wait.h>
   6 #include <unistd.h>
   7
   8 #define CHILDREN 7
   9
  10 int main(int argc, char *argv[]) {
  11   _Atomic int *sync = mmap(NULL, sizeof(int), PROT_READ | PROT_WRITE,
  12                            MAP_SHARED | MAP_ANONYMOUS, -1, 0);
  13   if (sync == MAP_FAILED)
  14     return 1;
  15   *sync = 0;
  16
  17   for (int i = 0; i < CHILDREN; i++) {
  18     pid_t pid = fork();
  19     if (!pid) {
  20       // child
  21       while (*sync == 0)
  22         ; // wait the parent in order to call execl simultaneously
  23       execl(argv[1], argv[1], NULL);
  24     } else if (pid == -1) {
  25       *sync = 1; // release all children
  26       return 1;
  27     }
  28   }
  29
  30   // parent
  31   *sync = 1; // start the program in all children simultaneously
  32   for (int i = 0; i < CHILDREN; i++)
  33     wait(NULL);
  34
  35   return 0;
  36 }