Fix stale pawn-hash comments (size, lock claim)

PAWN_HASH_TABLE_SIZE's "5.5Mb" comment predates iBishopColorScore
growing PAWN_HASH_ENTRY to 80 bytes (131072 * 80 == 10Mb, not 5.5Mb).

PawnHashLookup's "multi-probing scheme...to remove contention on MP
machines" doesn't describe the code: it's a single direct-indexed
probe into ctx->rgPawnHash, which is embedded per-thread inside
SEARCHER_THREAD_CONTEXT, so there's no cross-thread contention to
avoid in the first place.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

2 files changed, 5 insertions, 3 deletions

diff --git a/src/chess.h b/src/chess.h
index b0be749..7125cc7 100755
--- a/src/chess.h
+++ b/src/chess.h
@@ -1736,7 +1736,7 @@ typedef struct _PLY_INFO
 }
 PLY_INFO;
 
-#define PAWN_HASH_TABLE_SIZE (131072) // 5.5Mb (per thread)
+#define PAWN_HASH_TABLE_SIZE (131072) // 10Mb (per thread; sizeof(PAWN_HASH_ENTRY) == 80)
 typedef struct _PAWN_HASH_ENTRY
 {
     UINT64 u64Key;
diff --git a/src/pawnhash.c b/src/pawnhash.c
index 8af2138..23c0cb0 100644
--- a/src/pawnhash.c
+++ b/src/pawnhash.c
@@ -34,8 +34,10 @@ Routine description:
     POSITION.  If so, "check out" that entry and return a pointer to
     it.
 
-    Note: there is a multi-probing scheme in place to remove
-    contention on MP machines.
+    Note: a single direct-indexed probe, no multi-probing scheme --
+    ctx->rgPawnHash is embedded per-thread inside SEARCHER_THREAD_
+    CONTEXT (chess.h), so there's no cross-thread contention to
+    avoid here in the first place.
 
 Parameters: