📦 NEW: Pass full ttable between searches

src/search.rs

@@ -7,7 +7,7 @@ use crate::options::{get_num_threads, get_policy_temperature, is_chess960};
 use crate::search_tree::{MoveEdge, SearchTree};
 use crate::state::State;
 use crate::tablebase;
-use crate::transposition_table::{LRAllocator, TranspositionTable};
+use crate::transposition_table::{LRAllocator, LRTable};
 use crate::uci::{read_stdin, Tokens};
 
 const DEFAULT_MOVE_TIME_SECS: u64 = 10;
@@ -93,12 +93,16 @@ pub struct Search {
 }
 
 impl Search {
-    pub fn new(state: State, prev_table: TranspositionTable) -> Self {
-        let search_tree = SearchTree::new(state, TranspositionTable::empty(), prev_table);
+    pub fn new(state: State, table: LRTable) -> Self {
+        let search_tree = SearchTree::new(state, table);
         Self { search_tree }
     }
 
-    pub fn table(self) -> TranspositionTable {
+    pub fn reset_table(&mut self) {
+        self.search_tree.reset_table();
+    }
+
+    pub fn table(self) -> LRTable {
         self.search_tree.table()
     }
 

src/search_tree.rs

@@ -200,11 +200,7 @@ where
 }
 
 impl SearchTree {
-    pub fn new(
-        state: State,
-        current_table: TranspositionTable,
-        previous_table: TranspositionTable,
-    ) -> Self {
+    pub fn new(state: State, table: LRTable) -> Self {
         let tb_hits = 0.into();
 
         let root_table = TranspositionTable::for_root();
@@ -217,7 +213,7 @@ impl SearchTree {
         )
         .expect("Unable to create root node");
 
-        previous_table.lookup_into(&state, &mut root_node);
+        table.lookup_into_from_all(&state, &mut root_node);
 
         Self {
             root_state: state,
@@ -226,7 +222,7 @@ impl SearchTree {
             cpuct_root: get_cpuct_root(),
             policy_t: get_policy_temperature(),
             root_table,
-            ttable: LRTable::new(current_table, previous_table),
+            ttable: table,
             num_nodes: 1.into(),
             playouts: 0.into(),
             max_depth: 0.into(),
@@ -235,12 +231,17 @@ impl SearchTree {
         }
     }
 
+    pub fn reset_table(&mut self) {
+        self.ttable = LRTable::empty();
+        self.root_node.clear_children_links();
+    }
+
     fn flip_tables(&self) {
         self.ttable.flip_tables();
     }
 
-    pub fn table(self) -> TranspositionTable {
-        self.ttable.table()
+    pub fn table(self) -> LRTable {
+        self.ttable
     }
 
     pub fn num_nodes(&self) -> usize {

src/transposition_table.rs

@@ -32,10 +32,6 @@ impl TranspositionTable {
         Self { table, arena }
     }
 
-    pub fn is_empty(&self) -> bool {
-        self.table.is_empty()
-    }
-
     pub fn arena(&self) -> &Arena {
         &self.arena
     }
@@ -67,7 +63,7 @@ impl TranspositionTable {
             .map(|v| unsafe { &*v.load(Ordering::Relaxed) })
     }
 
-    pub fn lookup_into(&self, state: &State, dest: &mut PositionNode) {
+    pub fn lookup_into(&self, state: &State, dest: &mut PositionNode) -> bool {
         if let Some(src) = self.lookup(state) {
             dest.set_flag(src.flag());
 
@@ -77,6 +73,9 @@ impl TranspositionTable {
             for i in 0..lhs.len().min(rhs.len()) {
                 lhs[i].replace(&rhs[i]);
             }
+            true
+        } else {
+            false
         }
     }
 }
@@ -98,6 +97,10 @@ impl LRTable {
         }
     }
 
+    pub fn empty() -> Self {
+        Self::new(TranspositionTable::empty(), TranspositionTable::empty())
+    }
+
     pub fn is_arena_full(&self) -> bool {
         self.current_table().arena().full()
     }
@@ -114,6 +117,12 @@ impl LRTable {
         self.previous_table().lookup_into(state, dest);
     }
 
+    pub fn lookup_into_from_all(&self, state: &State, dest: &mut PositionNode) {
+        if !self.current_table().lookup_into(state, dest) {
+            self.previous_table().lookup_into(state, dest);
+        }
+    }
+
     pub fn is_left_current(&self) -> bool {
         self.is_left_current.load(Ordering::Relaxed)
     }
@@ -142,16 +151,6 @@ impl LRTable {
         );
     }
 
-    pub fn table(self) -> TranspositionTable {
-        if self.left.is_empty() {
-            self.right
-        } else if self.right.is_empty() || self.is_left_current() {
-            self.left
-        } else {
-            self.right
-        }
-    }
-
     pub fn flip_lock(&self) -> &Mutex<()> {
         &self.flip_lock
     }

src/uci.rs

@@ -9,7 +9,7 @@ use crate::search::Search;
 use crate::search_tree::print_size_list;
 use crate::state::State;
 use crate::tablebase::set_tablebase_directory;
-use crate::transposition_table::TranspositionTable;
+use crate::transposition_table::LRTable;
 
 pub type Tokens<'a> = SplitWhitespace<'a>;
 
@@ -18,7 +18,7 @@ const ENGINE_AUTHOR: &str = "Princess Lana";
 const VERSION: Option<&'static str> = option_env!("CARGO_PKG_VERSION");
 
 pub fn main() {
-    let mut search = Search::new(State::default(), TranspositionTable::empty());
+    let mut search = Search::new(State::default(), LRTable::empty());
 
     let mut next_line: Option<String> = None;
 
@@ -38,11 +38,11 @@ pub fn main() {
                     let option = UciOption::parse(tokens);
 
                     if let Some(opt) = option {
-                        opt.set();
+                        opt.set(&mut search);
                     }
                 }
                 "ucinewgame" => {
-                    search = Search::new(State::default(), TranspositionTable::empty());
+                    search = Search::new(State::default(), LRTable::empty());
                 }
                 "position" => {
                     if let Some(state) = State::from_tokens(tokens) {
@@ -129,15 +129,18 @@ impl UciOption {
         &self.value
     }
 
-    pub fn set(&self) {
+    pub fn set(&self, search: &mut Search) {
         match self.name().as_str() {
             "syzygypath" => {
                 if let Some(path) = self.value() {
                     set_tablebase_directory(path);
                 }
             }
             "threads" => self.set_option(set_num_threads),
-            "hash" => self.set_option(set_hash_size_mb),
+            "hash" => {
+                self.set_option(set_hash_size_mb);
+                search.reset_table();
+            }
             "cpuct" => self.set_option(set_cpuct),
             "cpuctroot" => self.set_option(set_cpuct_root),
             "cvisitsselection" => self.set_option(set_cvisits_selection),