From db27bb0c21e3c189352ccfb78a65fe66d6855cee Mon Sep 17 00:00:00 2001
From: Jean-loup Gailly <jloup@gailly.net>
Date: Sat, 8 May 2010 11:24:31 +0200
Subject: [PATCH] Distributed engine: Define board_bits2 and path2sstr

---
 board.c                   |  4 ++++
 board.h                   | 11 +++++++++++
 distributed/distributed.c | 26 ++++++++++++++++++++++++++
 distributed/distributed.h |  9 +++++++++
 uct/slave.c               |  5 +++--
 5 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/board.c b/board.c
index e1b83a7..d0fc7a6 100644
--- a/board.c
+++ b/board.c
@@ -148,6 +148,10 @@ board_resize(struct board *board, int size)
 #endif
 	board->size = size + 2 /* S_OFFBOARD margin */;
 	board->size2 = board_size(board) * board_size(board);
+
+	board->bits2 = 1;
+	while ((1 << board->bits2) < board->size2) board->bits2++;
+
 	if (board->b)
 		free(board->b);
 
diff --git a/board.h b/board.h
index 2b75d96..9a5f035 100644
--- a/board.h
+++ b/board.h
@@ -104,6 +104,7 @@ struct btraits {
 struct board {
 	int size; /* Including S_OFFBOARD margin - see below. */
 	int size2; /* size^2 */
+	int bits2; /* ceiling(log2(size2)) */
 	int captures[S_MAX];
 	float komi;
 	int handicap;
@@ -249,6 +250,16 @@ struct board {
 #define board_size2(b_) ((b_)->size2)
 #endif
 
+#if BOARD_SIZE == 19
+#  define board_bits2(b_) 9
+#elif BOARD_SIZE == 13
+#  define board_bits2(b_) 8
+#elif BOARD_SIZE == 9
+#  define board_bits2(b_) 7
+#else
+#  define board_bits2(b_) ((b_)->bits2)
+#endif
+
 #define board_at(b_, c) ((b_)->b[c])
 #define board_atxy(b_, x, y) ((b_)->b[(x) + board_size(b_) * (y)])
 
diff --git a/distributed/distributed.c b/distributed/distributed.c
index 1ee632f..215bcc7 100644
--- a/distributed/distributed.c
+++ b/distributed/distributed.c
@@ -100,6 +100,32 @@ static const struct time_info default_ti = {
 /* Maximum time (seconds) to wait for answers to genmoves. */
 #define MAX_GENMOVES_WAIT 0.1 /* 100 ms */
 
+
+/* Display a path as leaf<parent<grandparent...
+ * Returns the path string in a static buffer; it is NOT safe for
+ * anything but debugging - in particular, it is NOT thread-safe! */
+char *
+path2sstr(path_t path, struct board *b)
+{
+	/* Special case for pass and resign. */
+	if (path < 0) return coord2sstr((coord_t)path, b);
+
+	static char buf[16][64];
+	static int bi = 0;
+	char *b2;
+	b2 = buf[bi++ & 15];
+	*b2 = '\0';
+	char *s = b2;
+	char *end = b2 + 64;
+	coord_t leaf;
+	while ((leaf = leaf_coord(path, b)) != 0) {
+		s += snprintf(s, end - s, "%s<", coord2sstr(leaf, b));
+		path = parent_path(path, b);
+	}
+	if (s != b2) s[-1] = '\0';
+	return b2;
+}
+
 /* Dispatch a new gtp command to all slaves.
  * The slave lock must not be held upon entry and is released upon return.
  * args is empty or ends with '\n' */
diff --git a/distributed/distributed.h b/distributed/distributed.h
index 9f1e708..d436306 100644
--- a/distributed/distributed.h
+++ b/distributed/distributed.h
@@ -16,6 +16,14 @@ typedef int64_t path_t;
 #define PRIpath PRIx64
 #define PATH_T_MAX INT64_MAX
 
+#define hash_mask(bits) ((1<<(bits))-1)
+
+/* parent_path() must never be used if path might be pass or resign. */
+#define parent_path(path, board) ((path) >> board_bits2(board))
+#define leaf_coord(path, board) ((path) & hash_mask(board_bits2(board)))
+#define append_child(path, c, board) (((path) << board_bits2(board)) | (c))
+
+
 /* Stats exchanged between master and slave. They are always
  * incremental values to be added to what was last sent. */
 struct incr_stats {
@@ -35,6 +43,7 @@ struct move_stats2 {
 	struct move_stats amaf;
 };
 
+char *path2sstr(path_t path, struct board *b);
 struct engine *engine_distributed_init(char *arg, struct board *b);
 
 #endif
diff --git a/uct/slave.c b/uct/slave.c
index b1df4c2..8515058 100644
--- a/uct/slave.c
+++ b/uct/slave.c
@@ -76,8 +76,9 @@ receive_stats(struct uct *u, int size)
 			return false;
 
 		if (UDEBUGL(7))
-			fprintf(stderr, "read %5d/%d %6d %.3f %"PRIpath"\n", n, nodes,
-				is.incr.playouts, is.incr.value, is.coord_path);
+			fprintf(stderr, "read %5d/%d %6d %.3f %"PRIpath" %s\n", n, nodes,
+				is.incr.playouts, is.incr.value, is.coord_path,
+				path2sstr(is.coord_path, u->t->board));
 
 		/* TODO: update the stats in the tree. */
 	}
-- 
2.11.4.GIT