1 files changed, 68 insertions, 0 deletions
diff --git a/perf/benchmark-map.cc b/perf/benchmark-map.cc
new file mode 100644
index 000000000..f278a0c94
--- /dev/null
+++ b/perf/benchmark-map.cc
@@ -0,0 +1,68 @@
+/*
+ * Benchmarks for hb_map_t operations.
+ */
+#include "benchmark/benchmark.h"
+
+#include <cassert>
+#include <cstdlib>
+#include "hb.h"
+
+void RandomMap(unsigned size, hb_map_t* out) {
+  hb_map_clear(out);
+
+  srand(size);
+  for (unsigned i = 0; i < size; i++) {
+    while (true) {
+      hb_codepoint_t next = rand();
+      if (hb_map_has (out, next)) continue;
+
+      hb_map_set (out, next, rand ());
+      break;
+    }
+  }
+}
+
+/* Insert a single value into map of varying sizes. */
+static void BM_MapInsert(benchmark::State& state) {
+  unsigned map_size = state.range(0);
+
+  hb_map_t* original = hb_map_create ();
+  RandomMap(map_size, original);
+  assert(hb_map_get_population(original) == map_size);
+
+  auto needle = map_size / 2;
+  auto v = 0;
+  for (auto _ : state) {
+    // TODO(garretrieger): create a copy of the original map.
+    //                     Needs a hb_map_copy(..) in public api.
+
+    hb_map_set (original, needle++, v++);
+  }
+
+  hb_map_destroy(original);
+}
+BENCHMARK(BM_MapInsert)
+    ->Range(1 << 4, 1 << 20);
+
+/* Single value lookup on map of various sizes. */
+static void BM_MapLookup(benchmark::State& state) {
+  unsigned map_size = state.range(0);
+
+  hb_map_t* original = hb_map_create ();
+  RandomMap(map_size, original);
+  assert(hb_map_get_population(original) == map_size);
+
+  auto needle = map_size / 2;
+
+  for (auto _ : state) {
+    benchmark::DoNotOptimize(
+        hb_map_get (original, needle++));
+  }
+
+  hb_map_destroy(original);
+}
+BENCHMARK(BM_MapLookup)
+    ->Range(1 << 4, 1 << 20); // Map size
+
+
+BENCHMARK_MAIN();