chore: reorganize benchmarks (#13606)

benchmark/util.mjs

@@ -0,0 +1,17 @@
+export function report(event) {
+  const bench = event.target;
+  const timeMs = bench.stats.mean * 1000;
+  const time =
+    timeMs < 10
+      ? `${Math.round(timeMs * 1000) / 1000}ms`
+      : `${Math.round(timeMs)}ms`;
+  const msg = `${bench.name}: ${formatNumber(bench.hz)} ops/sec ±${
+    Math.round(bench.stats.rme * 100) / 100
+  }% (${time})`;
+  console.log(msg);
+}
+
+function formatNumber(x) {
+  if (x < 100) return `${Math.round(x * 100) / 100}`;
+  return `${Math.round(x)}`.replace(/\d(?=(?:\d{3})+$)/g, "$&_");
+}