bench: add board place benchmark

benches/board.rs

@@ -0,0 +1,29 @@
+use criterion::{criterion_group, criterion_main, Criterion, Throughput};
+use othello::repr::{Board, Piece};
+
+fn fill_board(loops: usize) {
+    let mut board = Board::new();
+    board.place_unchecked((0, 1).into(), Piece::White);
+    board.place_unchecked((0, 2).into(), Piece::Black);
+    board.place_unchecked((0, 3).into(), Piece::Black);
+    board.place_unchecked((0, 4).into(), Piece::Black);
+    for _ in 0..loops {
+        let mut board = board;
+        let _ = board.place((0, 5).into(), Piece::White);
+    }
+}
+
+fn criterion_benchmark(c: &mut Criterion) {
+    let mut group = c.benchmark_group("board");
+
+    const LOOPS: usize = 1000;
+
+    group.throughput(Throughput::Elements(LOOPS as u64));
+    group.bench_function("board_place", |b| {
+        b.iter(|| fill_board(LOOPS));
+    });
+    group.finish();
+}
+
+criterion_group!(benches, criterion_benchmark);
+criterion_main!(benches);