stellar

commit 1ecc793cac68e9c8768895ee4d358cb6b3ce1c31
parent eb0c42bd2bf2f52666067bf7f1fad41dfe4948a9
Author: Dimitrije Dobrota <mail@dimitrijedobrota.com>
Date:   Fri, 28 Jul 2023 15:28:19 +0200

Add Multithreaded PERFT

Diffstat:
M
src/engine.c
 | 
119
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------

1 file changed, 92 insertions(+), 27 deletions(-)
diff --git a/src/engine.c b/src/engine.c
@@ -826,9 +826,9 @@ void uci_loop(void) {
 struct MoveList_T moveList[10];
 long              nodes;
 
-void perft_driver(CBoard_T board, int depth) {
+void perft_driver(CBoard_T board, struct MoveList_T *moveList, int depth, unsigned long long *nodes) {
   if (depth == 0) {
-    nodes++;
+    (*nodes)++;
     return;
   }
 
@@ -839,8 +839,9 @@ void perft_driver(CBoard_T board, int depth) {
     CBoard_copy(board, copy);
     if (!Move_make(MoveList_move(list, i), copy, 0))
       continue;
-    perft_driver(copy, depth - 1);
+    perft_driver(copy, moveList, depth - 1, nodes);
   }
+
   MoveList_reset(list);
   CBoard_free(&copy);
 }
@@ -856,24 +857,96 @@ void perft_test(CBoard_T board, int depth) {
   for (int i = 0; i < MoveList_size(list); i++) {
     CBoard_copy(board, copy);
     Move move = MoveList_move(list, i);
-    if (!Move_make(MoveList_move(list, i), copy, 0))
-      continue;
-    long cummulative_nodes = nodes;
-    perft_driver(copy, depth - 1);
-    long old_nodes = nodes - cummulative_nodes;
-    printf("%s%s: %ld\n", square_to_coordinates[Move_source(move)],
-           square_to_coordinates[Move_target(move)], old_nodes);
+    if (!Move_make(MoveList_move(list, i), copy, 0)) continue;
+    unsigned long long node = 0;
+    perft_driver(copy, moveList, depth - 1, &node);
+    printf("%s%s: %llu\n", square_to_coordinates[Move_source(move)],
+           square_to_coordinates[Move_target(move)], node);
+    nodes+=node;
   }
   MoveList_reset(list);
   CBoard_free(&copy);
 
   printf("\nNodes searched: %ld\n\n", nodes);
-  return;
   printf("\n    Depth: %d\n", depth);
   printf("    Nodes: %ld\n", nodes);
   printf("     Time: %ld\n\n", get_time_ms() - start);
 }
 
+ #include <semaphore.h>
+ #include <pthread.h>
+
+typedef struct perf_shared perf_shared;
+struct perf_shared {
+  CBoard_T board;
+  MoveList_T list;
+  int depth;
+  sem_t* mutex;
+  int* index;
+  sem_t* finish;
+  unsigned long long *total;
+};
+
+void* perft_thread(void *arg) {
+  perf_shared *shared = (perf_shared *)arg;
+  CBoard_T board = CBoard_new();
+  unsigned long long node_count = 0;
+
+  struct MoveList_T moveList[10];
+
+  while(1) {
+    sem_wait(shared->mutex);
+    *shared->total += node_count;
+    if(*shared->index >= MoveList_size(shared->list)) {
+        sem_post(shared->mutex);
+        break;
+    }
+    Move move = MoveList_move(shared->list, (*shared->index)++);
+    sem_post(shared->mutex);
+
+    CBoard_copy(shared->board, board);
+    if(!Move_make(move, board, 0)) continue;
+
+    node_count = 0;
+    perft_driver(board, moveList, shared->depth, &node_count);
+    printf("%s%s: %llu\n", square_to_coordinates[Move_source(move)],
+           square_to_coordinates[Move_target(move)], node_count);
+  }
+  CBoard_free(&board);
+  sem_post(shared->finish);
+  return NULL;
+}
+
+void perft_test_threaded(CBoard_T board, int depth) {
+  MoveList_T list = MoveList_generate(NULL, board);
+  int size = 8;
+
+  unsigned long long total = 0;
+  perf_shared shared[size];
+  pthread_t threads[size];
+  sem_t mutex, finish;
+
+
+  int index = 0;
+  sem_init(&mutex, 0, 1);
+  sem_init(&finish, 0, 0);
+  for(int i=0; i<size; i++) {
+    shared[i].board = board;
+    shared[i].list = list;
+    shared[i].depth = depth - 1;
+    shared[i].mutex = &mutex;
+    shared[i].index = &index;
+    shared[i].finish = &finish;
+    shared[i].total = &total;
+    pthread_create(threads + i, NULL, perft_thread, (void *)(shared + i));
+  }
+
+  for(int i=0; i<size; i++) sem_wait(&finish);
+  MoveList_free(&list);
+
+  printf("Nodes processed: %llu\n", total);
+}
+
 /* MAIN */
 
 void init_all() {
@@ -881,23 +954,15 @@ void init_all() {
   init_sliders_attacks();
 }
 
+
 int main(void) {
   init_all();
-  int debug = 1;
-  if (debug) {
-    CBoard_T      board = NULL;
-    MoveList_T    list = NULL;
-    Instruction_T inst = NULL;
-    (void)inst;
-    (void)list;
-
-    board = CBoard_fromFEN(board, tricky_position);
-    CBoard_print(board);
-    /* MoveList_print(MoveList_generate(NULL, board)); */
-    perft_test(board, 5);
-    /* search_position(board, 5); */
-    CBoard_free(&board);
-  } else
-    uci_loop();
+
+  CBoard_T      board = NULL;
+  board = CBoard_fromFEN(board, start_position);
+  CBoard_print(board);
+  //perft_test(board, 7);
+  perft_test_threaded(board, 7);
+  CBoard_free(&board);
   return 0;
 }