diff --git a/tests/benchmark_main.cpp b/tests/benchmark_main.cpp
new file mode 100644
index 0000000..4fbeb07
--- /dev/null
+++ b/tests/benchmark_main.cpp
@@ -0,0 +1,197 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "benchmark.h"
+
+#include <regex.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <string>
+#include <map>
+
+static int64_t gBytesProcessed;
+static int64_t gBenchmarkTotalTimeNs;
+static int64_t gBenchmarkStartTimeNs;
+
+typedef std::map<std::string, ::testing::Benchmark*> BenchmarkMap;
+typedef BenchmarkMap::iterator BenchmarkMapIt;
+static BenchmarkMap gBenchmarks;
+
+static int Round(int n) {
+  int base = 1;
+  while (base*10 < n) {
+    base *= 10;
+  }
+  if (n < 2*base) {
+    return 2*base;
+  }
+  if (n < 5*base) {
+    return 5*base;
+  }
+  return 10*base;
+}
+
+static int64_t NanoTime() {
+  struct timespec t;
+  t.tv_sec = t.tv_nsec = 0;
+  clock_gettime(CLOCK_MONOTONIC, &t);
+  return static_cast<int64_t>(t.tv_sec) * 1000000000LL + t.tv_nsec;
+}
+
+namespace testing {
+
+Benchmark* Benchmark::Arg(int arg) {
+  args_.push_back(arg);
+  return this;
+}
+
+bool Benchmark::ShouldRun(int argc, char* argv[]) {
+  if (argc == 1) {
+    return true;  // With no arguments, we run all benchmarks.
+  }
+  // Otherwise, we interpret each argument as a regular expression and
+  // see if any of our benchmarks match.
+  for (int i = 1; i < argc; i++) {
+    regex_t re;
+    if (regcomp(&re, argv[i], 0) != 0) {
+      fprintf(stderr, "couldn't compile \"%s\" as a regular expression!\n", argv[i]);
+      exit(EXIT_FAILURE);
+    }
+    int match = regexec(&re, name_, 0, NULL, 0);
+    regfree(&re);
+    if (match != REG_NOMATCH) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void Benchmark::Register(const char* name, void (*fn)(int), void (*fn_range)(int, int)) {
+  name_ = name;
+  fn_ = fn;
+  fn_range_ = fn_range;
+
+  if (fn_ == NULL && fn_range_ == NULL) {
+    fprintf(stderr, "%s: missing function\n", name_);
+    exit(EXIT_FAILURE);
+  }
+
+  gBenchmarks.insert(std::make_pair(name, this));
+}
+
+void Benchmark::Run() {
+  if (args_.empty()) {
+    fprintf(stderr, "%s: no args!\n", name_);
+    exit(EXIT_FAILURE);
+  }
+  for (size_t i = 0; i < args_.size(); ++i) {
+    RunWithArg(args_[i]);
+  }
+}
+
+void Benchmark::RunRepeatedlyWithArg(int iterations, int arg) {
+  gBytesProcessed = 0;
+  gBenchmarkTotalTimeNs = 0;
+  gBenchmarkStartTimeNs = NanoTime();
+  if (fn_ != NULL) {
+    fn_(iterations);
+  } else {
+    fn_range_(iterations, arg);
+  }
+  if (gBenchmarkStartTimeNs != 0) {
+    gBenchmarkTotalTimeNs += NanoTime() - gBenchmarkStartTimeNs;
+  }
+}
+
+void Benchmark::RunWithArg(int arg) {
+  // run once in case it's expensive
+  int iterations = 1;
+  RunRepeatedlyWithArg(iterations, arg);
+  while (gBenchmarkTotalTimeNs < 1e9 && iterations < 1e9) {
+    int last = iterations;
+    if (gBenchmarkTotalTimeNs/iterations == 0) {
+      iterations = 1e9;
+    } else {
+      iterations = 1e9 / (gBenchmarkTotalTimeNs/iterations);
+    }
+    iterations = std::max(last + 1, std::min(iterations + iterations/2, 100*last));
+    iterations = Round(iterations);
+    RunRepeatedlyWithArg(iterations, arg);
+  }
+
+  char throughput[100];
+  throughput[0] = '\0';
+  if (gBenchmarkTotalTimeNs > 0 && gBytesProcessed > 0) {
+    double mib_processed = static_cast<double>(gBytesProcessed)/1e6;
+    double seconds = static_cast<double>(gBenchmarkTotalTimeNs)/1e9;
+    snprintf(throughput, sizeof(throughput), " %8.2f MiB/s", mib_processed/seconds);
+  }
+
+  char full_name[100];
+  if (fn_range_ != NULL) {
+    if (arg >= (1<<20)) {
+      snprintf(full_name, sizeof(full_name), "%s/%dM", name_, arg/(1<<20));
+    } else if (arg >= (1<<10)) {
+      snprintf(full_name, sizeof(full_name), "%s/%dK", name_, arg/(1<<10));
+    } else {
+      snprintf(full_name, sizeof(full_name), "%s/%d", name_, arg);
+    }
+  } else {
+    snprintf(full_name, sizeof(full_name), "%s", name_);
+  }
+
+  printf("%-20s %10lld %10lld%s\n", full_name,
+         static_cast<int64_t>(iterations), gBenchmarkTotalTimeNs/iterations, throughput);
+  fflush(stdout);
+}
+
+}  // namespace testing
+
+void SetBenchmarkBytesProcessed(int64_t x) {
+  gBytesProcessed = x;
+}
+
+void StopBenchmarkTiming() {
+  if (gBenchmarkStartTimeNs != 0) {
+    gBenchmarkTotalTimeNs += NanoTime() - gBenchmarkStartTimeNs;
+  }
+  gBenchmarkStartTimeNs = 0;
+}
+
+void StartBenchmarkTiming() {
+  if (gBenchmarkStartTimeNs == 0) {
+    gBenchmarkStartTimeNs = NanoTime();
+  }
+}
+
+int main(int argc, char* argv[]) {
+  if (gBenchmarks.empty()) {
+    fprintf(stderr, "no benchmarks!\n");
+    exit(EXIT_FAILURE);
+  }
+
+  printf("%-20s %10s %10s\n", "", "iterations", "ns/op");
+  fflush(stdout);
+
+  for (BenchmarkMapIt it = gBenchmarks.begin(); it != gBenchmarks.end(); ++it) {
+    ::testing::Benchmark* b = it->second;
+    if (b->ShouldRun(argc, argv)) {
+      b->Run();
+    }
+  }
+  return 0;
+}