Added texture update test.

client/deps/glbench/src/bench.cc

-// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "main.h"
-#include "testbase.h"
-
-uint64_t TimeTest(glbench::TestBase* test, int iter) {
-  SwapBuffers();
-  glFinish();
-  uint64_t time1 = GetUTime();
-  test->TestFunc(iter);
-  glFinish();
-  uint64_t time2 = GetUTime();
-  return time2 - time1;
-}
-
-// Benchmark some draw commands, by running it many times.
-// We want to measure the marginal cost, so we try more and more iterations
-// until we get a somewhat linear response (to eliminate constant cost), and we
-// do a linear regression on a few samples.
-bool Bench(glbench::TestBase* test, float *slope, int64_t *bias) {
-  // Do one iteration in case the driver needs to set up states.
-  if (TimeTest(test, 1) > MAX_ITERATION_DURATION_MS)
-    return false;
-  int64_t count = 0;
-  int64_t sum_x = 0;
-  int64_t sum_y = 0;
-  int64_t sum_xy = 0;
-  int64_t sum_x2 = 0;
-  uint64_t last_time = 0;
-  bool do_count = false;
-  uint64_t iter;
-  for (iter = 8; iter < 1<<30; iter *= 2) {
-    uint64_t time = TimeTest(test, iter);
-    if (last_time > 0 && (time > last_time * 1.8))
-      do_count = true;
-    last_time = time;
-    if (do_count) {
-      ++count;
-      sum_x += iter;
-      sum_y += time;
-      sum_xy += iter * time;
-      sum_x2 += iter * iter;
-    }
-    if ((time >= 500000 && count > 4))
-      break;
-  }
-  if (count < 2) {
-    *slope = 0.f;
-    *bias = 0;
-  }
-  *slope = static_cast<float>(sum_x * sum_y - count * sum_xy) /
-    (sum_x * sum_x - count * sum_x2);
-  *bias = (sum_x * sum_xy - sum_x2 * sum_y) / (sum_x * sum_x - count * sum_x2);
-  return true;
-}