[Bug tree-optimization/67816] [6 Regression] ICE in duplicate_thread_path, 186.crafty fails to build

["rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67816

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Seen with r228349 btw.  Delta-reduced testcase:

typedef struct {
    int path[65];
} CHESS_PATH;
extern int early_exit;
extern int number_of_solutions;
extern int solutions[10];
extern int solution_type;
extern int iteration_depth;
extern int hash_table_size;
extern int *last[65];
extern signed char searched_this_root_move[256];
extern unsigned int root_nodes[256];
extern CHESS_PATH pv[65];
int Iterate(int wtm, int search_type, int root_list_done)
{
  int *mvp;
  int i, value=0, time_used;
  int correct, correct_count, material=0, sorted, temp;
  for (; iteration_depth<=60; iteration_depth++) {
      for (mvp=last[0]; mvp<last[1]; mvp++)
        searched_this_root_move[mvp-last[0]]=0;
      for (i=0; i<number_of_solutions; i++) {
          if (!solution_type) { 
              if (solutions[i] == pv[1].path[1]) correct=1;         }
          else if (solutions[i] == pv[1].path[1]) correct=0;
      }
      if (correct) correct_count++;
      if (correct_count >= early_exit) break;
      do {
          sorted=1;
          for (mvp=last[0]+1; mvp<last[1]-1; mvp++) {
              if (root_nodes[mvp-last[0]] < root_nodes[mvp-last[0]+1]) {
                  temp=*mvp;
                  *mvp=*(mvp+1);
                  *(mvp+1)=temp;
                  temp=root_nodes[mvp-last[0]];
                  root_nodes[mvp-last[0]]=root_nodes[mvp-last[0]+1];
                  root_nodes[mvp-last[0]+1]=temp;
                  sorted=0;
              }
          }
      }
      while(!sorted);
  }
}