Update V8 to r4588

We're using WebKit r58033, as used by
http://src.chromium.org/svn/releases/5.0.387.0/DEPS
This requires http://v8.googlecode.com/svn/trunk@4465 but this version has a
crashing bug for ARM. Instead we use http://v8.googlecode.com/svn/trunk@4588,
which is used by http://src.chromium.org/svn/releases/6.0.399.0/DEPS

Note that a trivial bug fix was required in arm/codegen-arm.cc. This is guarded
with ANDROID. See http://code.google.com/p/v8/issues/detail?id=703

Change-Id: I459647a8286c4f8c7405f0c5581ecbf051a6f1e8
diff --git a/test/cctest/test-profile-generator.cc b/test/cctest/test-profile-generator.cc
new file mode 100644
index 0000000..e5850c9
--- /dev/null
+++ b/test/cctest/test-profile-generator.cc
@@ -0,0 +1,497 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+//
+// Tests of profiles generator and utilities.
+
+#ifdef ENABLE_LOGGING_AND_PROFILING
+
+#include "v8.h"
+#include "profile-generator-inl.h"
+#include "cctest.h"
+
+namespace i = v8::internal;
+
+using i::CodeEntry;
+using i::CodeMap;
+using i::CpuProfile;
+using i::CpuProfilesCollection;
+using i::ProfileNode;
+using i::ProfileTree;
+using i::ProfileGenerator;
+using i::SampleRateCalculator;
+using i::TickSample;
+using i::Vector;
+
+
+TEST(ProfileNodeFindOrAddChild) {
+  ProfileNode node(NULL, NULL);
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  ProfileNode* childNode1 = node.FindOrAddChild(&entry1);
+  CHECK_NE(NULL, childNode1);
+  CHECK_EQ(childNode1, node.FindOrAddChild(&entry1));
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  ProfileNode* childNode2 = node.FindOrAddChild(&entry2);
+  CHECK_NE(NULL, childNode2);
+  CHECK_NE(childNode1, childNode2);
+  CHECK_EQ(childNode1, node.FindOrAddChild(&entry1));
+  CHECK_EQ(childNode2, node.FindOrAddChild(&entry2));
+  CodeEntry entry3(i::Logger::FUNCTION_TAG, "", "ccc", "", 0);
+  ProfileNode* childNode3 = node.FindOrAddChild(&entry3);
+  CHECK_NE(NULL, childNode3);
+  CHECK_NE(childNode1, childNode3);
+  CHECK_NE(childNode2, childNode3);
+  CHECK_EQ(childNode1, node.FindOrAddChild(&entry1));
+  CHECK_EQ(childNode2, node.FindOrAddChild(&entry2));
+  CHECK_EQ(childNode3, node.FindOrAddChild(&entry3));
+}
+
+
+namespace {
+
+class ProfileTreeTestHelper {
+ public:
+  explicit ProfileTreeTestHelper(const ProfileTree* tree)
+      : tree_(tree) { }
+
+  ProfileNode* Walk(CodeEntry* entry1,
+                    CodeEntry* entry2 = NULL,
+                    CodeEntry* entry3 = NULL) {
+    ProfileNode* node = tree_->root();
+    node = node->FindChild(entry1);
+    if (node == NULL) return NULL;
+    if (entry2 != NULL) {
+      node = node->FindChild(entry2);
+      if (node == NULL) return NULL;
+    }
+    if (entry3 != NULL) {
+      node = node->FindChild(entry3);
+    }
+    return node;
+  }
+
+ private:
+  const ProfileTree* tree_;
+};
+
+}  // namespace
+
+TEST(ProfileTreeAddPathFromStart) {
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  CodeEntry entry3(i::Logger::FUNCTION_TAG, "", "ccc", "", 0);
+  ProfileTree tree;
+  ProfileTreeTestHelper helper(&tree);
+  CHECK_EQ(NULL, helper.Walk(&entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+
+  CodeEntry* path[] = {NULL, &entry1, NULL, &entry2, NULL, NULL, &entry3, NULL};
+  Vector<CodeEntry*> path_vec(path, sizeof(path) / sizeof(path[0]));
+  tree.AddPathFromStart(path_vec);
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+  ProfileNode* node1 = helper.Walk(&entry1);
+  CHECK_NE(NULL, node1);
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(0, node1->self_ticks());
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry3));
+  ProfileNode* node2 = helper.Walk(&entry1, &entry2);
+  CHECK_NE(NULL, node2);
+  CHECK_NE(node1, node2);
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(0, node2->self_ticks());
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry2));
+  ProfileNode* node3 = helper.Walk(&entry1, &entry2, &entry3);
+  CHECK_NE(NULL, node3);
+  CHECK_NE(node1, node3);
+  CHECK_NE(node2, node3);
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(1, node3->self_ticks());
+
+  tree.AddPathFromStart(path_vec);
+  CHECK_EQ(node1, helper.Walk(&entry1));
+  CHECK_EQ(node2, helper.Walk(&entry1, &entry2));
+  CHECK_EQ(node3, helper.Walk(&entry1, &entry2, &entry3));
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(0, node1->self_ticks());
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(0, node2->self_ticks());
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(2, node3->self_ticks());
+
+  CodeEntry* path2[] = {&entry1, &entry2, &entry2};
+  Vector<CodeEntry*> path2_vec(path2, sizeof(path2) / sizeof(path2[0]));
+  tree.AddPathFromStart(path2_vec);
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+  CHECK_EQ(node1, helper.Walk(&entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry3));
+  CHECK_EQ(node2, helper.Walk(&entry1, &entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry1));
+  CHECK_EQ(node3, helper.Walk(&entry1, &entry2, &entry3));
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(2, node3->self_ticks());
+  ProfileNode* node4 = helper.Walk(&entry1, &entry2, &entry2);
+  CHECK_NE(NULL, node4);
+  CHECK_NE(node3, node4);
+  CHECK_EQ(0, node4->total_ticks());
+  CHECK_EQ(1, node4->self_ticks());
+}
+
+
+TEST(ProfileTreeAddPathFromEnd) {
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  CodeEntry entry3(i::Logger::FUNCTION_TAG, "", "ccc", "", 0);
+  ProfileTree tree;
+  ProfileTreeTestHelper helper(&tree);
+  CHECK_EQ(NULL, helper.Walk(&entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+
+  CodeEntry* path[] = {NULL, &entry3, NULL, &entry2, NULL, NULL, &entry1, NULL};
+  Vector<CodeEntry*> path_vec(path, sizeof(path) / sizeof(path[0]));
+  tree.AddPathFromEnd(path_vec);
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+  ProfileNode* node1 = helper.Walk(&entry1);
+  CHECK_NE(NULL, node1);
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(0, node1->self_ticks());
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry3));
+  ProfileNode* node2 = helper.Walk(&entry1, &entry2);
+  CHECK_NE(NULL, node2);
+  CHECK_NE(node1, node2);
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(0, node2->self_ticks());
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry2));
+  ProfileNode* node3 = helper.Walk(&entry1, &entry2, &entry3);
+  CHECK_NE(NULL, node3);
+  CHECK_NE(node1, node3);
+  CHECK_NE(node2, node3);
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(1, node3->self_ticks());
+
+  tree.AddPathFromEnd(path_vec);
+  CHECK_EQ(node1, helper.Walk(&entry1));
+  CHECK_EQ(node2, helper.Walk(&entry1, &entry2));
+  CHECK_EQ(node3, helper.Walk(&entry1, &entry2, &entry3));
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(0, node1->self_ticks());
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(0, node2->self_ticks());
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(2, node3->self_ticks());
+
+  CodeEntry* path2[] = {&entry2, &entry2, &entry1};
+  Vector<CodeEntry*> path2_vec(path2, sizeof(path2) / sizeof(path2[0]));
+  tree.AddPathFromEnd(path2_vec);
+  CHECK_EQ(NULL, helper.Walk(&entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry3));
+  CHECK_EQ(node1, helper.Walk(&entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry1));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry3));
+  CHECK_EQ(node2, helper.Walk(&entry1, &entry2));
+  CHECK_EQ(NULL, helper.Walk(&entry1, &entry2, &entry1));
+  CHECK_EQ(node3, helper.Walk(&entry1, &entry2, &entry3));
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(2, node3->self_ticks());
+  ProfileNode* node4 = helper.Walk(&entry1, &entry2, &entry2);
+  CHECK_NE(NULL, node4);
+  CHECK_NE(node3, node4);
+  CHECK_EQ(0, node4->total_ticks());
+  CHECK_EQ(1, node4->self_ticks());
+}
+
+
+TEST(ProfileTreeCalculateTotalTicks) {
+  ProfileTree empty_tree;
+  CHECK_EQ(0, empty_tree.root()->total_ticks());
+  CHECK_EQ(0, empty_tree.root()->self_ticks());
+  empty_tree.CalculateTotalTicks();
+  CHECK_EQ(0, empty_tree.root()->total_ticks());
+  CHECK_EQ(0, empty_tree.root()->self_ticks());
+  empty_tree.root()->IncrementSelfTicks();
+  CHECK_EQ(0, empty_tree.root()->total_ticks());
+  CHECK_EQ(1, empty_tree.root()->self_ticks());
+  empty_tree.CalculateTotalTicks();
+  CHECK_EQ(1, empty_tree.root()->total_ticks());
+  CHECK_EQ(1, empty_tree.root()->self_ticks());
+
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  CodeEntry* e1_path[] = {&entry1};
+  Vector<CodeEntry*> e1_path_vec(
+      e1_path, sizeof(e1_path) / sizeof(e1_path[0]));
+  CodeEntry* e1_e2_path[] = {&entry1, &entry2};
+  Vector<CodeEntry*> e1_e2_path_vec(
+      e1_e2_path, sizeof(e1_e2_path) / sizeof(e1_e2_path[0]));
+
+  ProfileTree flat_tree;
+  ProfileTreeTestHelper flat_helper(&flat_tree);
+  flat_tree.AddPathFromStart(e1_path_vec);
+  flat_tree.AddPathFromStart(e1_path_vec);
+  flat_tree.AddPathFromStart(e1_e2_path_vec);
+  flat_tree.AddPathFromStart(e1_e2_path_vec);
+  flat_tree.AddPathFromStart(e1_e2_path_vec);
+  // Results in {root,0,0} -> {entry1,0,2} -> {entry2,0,3}
+  CHECK_EQ(0, flat_tree.root()->total_ticks());
+  CHECK_EQ(0, flat_tree.root()->self_ticks());
+  ProfileNode* node1 = flat_helper.Walk(&entry1);
+  CHECK_NE(NULL, node1);
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(2, node1->self_ticks());
+  ProfileNode* node2 = flat_helper.Walk(&entry1, &entry2);
+  CHECK_NE(NULL, node2);
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(3, node2->self_ticks());
+  flat_tree.CalculateTotalTicks();
+  // Must calculate {root,5,0} -> {entry1,5,2} -> {entry2,3,3}
+  CHECK_EQ(5, flat_tree.root()->total_ticks());
+  CHECK_EQ(0, flat_tree.root()->self_ticks());
+  CHECK_EQ(5, node1->total_ticks());
+  CHECK_EQ(2, node1->self_ticks());
+  CHECK_EQ(3, node2->total_ticks());
+  CHECK_EQ(3, node2->self_ticks());
+
+  CodeEntry* e2_path[] = {&entry2};
+  Vector<CodeEntry*> e2_path_vec(
+      e2_path, sizeof(e2_path) / sizeof(e2_path[0]));
+  CodeEntry entry3(i::Logger::FUNCTION_TAG, "", "ccc", "", 0);
+  CodeEntry* e3_path[] = {&entry3};
+  Vector<CodeEntry*> e3_path_vec(
+      e3_path, sizeof(e3_path) / sizeof(e3_path[0]));
+
+  ProfileTree wide_tree;
+  ProfileTreeTestHelper wide_helper(&wide_tree);
+  wide_tree.AddPathFromStart(e1_path_vec);
+  wide_tree.AddPathFromStart(e1_path_vec);
+  wide_tree.AddPathFromStart(e1_e2_path_vec);
+  wide_tree.AddPathFromStart(e2_path_vec);
+  wide_tree.AddPathFromStart(e2_path_vec);
+  wide_tree.AddPathFromStart(e2_path_vec);
+  wide_tree.AddPathFromStart(e3_path_vec);
+  wide_tree.AddPathFromStart(e3_path_vec);
+  wide_tree.AddPathFromStart(e3_path_vec);
+  wide_tree.AddPathFromStart(e3_path_vec);
+  // Results in            -> {entry1,0,2} -> {entry2,0,1}
+  //            {root,0,0} -> {entry2,0,3}
+  //                       -> {entry3,0,4}
+  CHECK_EQ(0, wide_tree.root()->total_ticks());
+  CHECK_EQ(0, wide_tree.root()->self_ticks());
+  node1 = wide_helper.Walk(&entry1);
+  CHECK_NE(NULL, node1);
+  CHECK_EQ(0, node1->total_ticks());
+  CHECK_EQ(2, node1->self_ticks());
+  ProfileNode* node1_2 = wide_helper.Walk(&entry1, &entry2);
+  CHECK_NE(NULL, node1_2);
+  CHECK_EQ(0, node1_2->total_ticks());
+  CHECK_EQ(1, node1_2->self_ticks());
+  node2 = wide_helper.Walk(&entry2);
+  CHECK_NE(NULL, node2);
+  CHECK_EQ(0, node2->total_ticks());
+  CHECK_EQ(3, node2->self_ticks());
+  ProfileNode* node3 = wide_helper.Walk(&entry3);
+  CHECK_NE(NULL, node3);
+  CHECK_EQ(0, node3->total_ticks());
+  CHECK_EQ(4, node3->self_ticks());
+  wide_tree.CalculateTotalTicks();
+  // Calculates             -> {entry1,3,2} -> {entry2,1,1}
+  //            {root,10,0} -> {entry2,3,3}
+  //                        -> {entry3,4,4}
+  CHECK_EQ(10, wide_tree.root()->total_ticks());
+  CHECK_EQ(0, wide_tree.root()->self_ticks());
+  CHECK_EQ(3, node1->total_ticks());
+  CHECK_EQ(2, node1->self_ticks());
+  CHECK_EQ(1, node1_2->total_ticks());
+  CHECK_EQ(1, node1_2->self_ticks());
+  CHECK_EQ(3, node2->total_ticks());
+  CHECK_EQ(3, node2->self_ticks());
+  CHECK_EQ(4, node3->total_ticks());
+  CHECK_EQ(4, node3->self_ticks());
+}
+
+
+static inline i::Address ToAddress(int n) {
+  return reinterpret_cast<i::Address>(n);
+}
+
+TEST(CodeMapAddCode) {
+  CodeMap code_map;
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  CodeEntry entry3(i::Logger::FUNCTION_TAG, "", "ccc", "", 0);
+  CodeEntry entry4(i::Logger::FUNCTION_TAG, "", "ddd", "", 0);
+  code_map.AddCode(ToAddress(0x1500), &entry1, 0x200);
+  code_map.AddCode(ToAddress(0x1700), &entry2, 0x100);
+  code_map.AddCode(ToAddress(0x1900), &entry3, 0x50);
+  code_map.AddCode(ToAddress(0x1950), &entry4, 0x10);
+  CHECK_EQ(NULL, code_map.FindEntry(0));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1500 - 1)));
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1500)));
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1500 + 0x100)));
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1500 + 0x200 - 1)));
+  CHECK_EQ(&entry2, code_map.FindEntry(ToAddress(0x1700)));
+  CHECK_EQ(&entry2, code_map.FindEntry(ToAddress(0x1700 + 0x50)));
+  CHECK_EQ(&entry2, code_map.FindEntry(ToAddress(0x1700 + 0x100 - 1)));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1700 + 0x100)));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1900 - 1)));
+  CHECK_EQ(&entry3, code_map.FindEntry(ToAddress(0x1900)));
+  CHECK_EQ(&entry3, code_map.FindEntry(ToAddress(0x1900 + 0x28)));
+  CHECK_EQ(&entry4, code_map.FindEntry(ToAddress(0x1950)));
+  CHECK_EQ(&entry4, code_map.FindEntry(ToAddress(0x1950 + 0x7)));
+  CHECK_EQ(&entry4, code_map.FindEntry(ToAddress(0x1950 + 0x10 - 1)));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1950 + 0x10)));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0xFFFFFFFF)));
+}
+
+
+TEST(CodeMapMoveAndDeleteCode) {
+  CodeMap code_map;
+  CodeEntry entry1(i::Logger::FUNCTION_TAG, "", "aaa", "", 0);
+  CodeEntry entry2(i::Logger::FUNCTION_TAG, "", "bbb", "", 0);
+  code_map.AddCode(ToAddress(0x1500), &entry1, 0x200);
+  code_map.AddCode(ToAddress(0x1700), &entry2, 0x100);
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1500)));
+  CHECK_EQ(&entry2, code_map.FindEntry(ToAddress(0x1700)));
+  code_map.MoveCode(ToAddress(0x1500), ToAddress(0x1800));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1500)));
+  CHECK_EQ(&entry2, code_map.FindEntry(ToAddress(0x1700)));
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1800)));
+  code_map.DeleteCode(ToAddress(0x1700));
+  CHECK_EQ(NULL, code_map.FindEntry(ToAddress(0x1700)));
+  CHECK_EQ(&entry1, code_map.FindEntry(ToAddress(0x1800)));
+}
+
+
+namespace {
+
+class TestSetup {
+ public:
+  TestSetup()
+      : old_flag_prof_browser_mode_(i::FLAG_prof_browser_mode) {
+    i::FLAG_prof_browser_mode = false;
+  }
+
+  ~TestSetup() {
+    i::FLAG_prof_browser_mode = old_flag_prof_browser_mode_;
+  }
+
+ private:
+  bool old_flag_prof_browser_mode_;
+};
+
+}  // namespace
+
+TEST(RecordTickSample) {
+  TestSetup test_setup;
+  CpuProfilesCollection profiles;
+  profiles.StartProfiling("", 1);
+  ProfileGenerator generator(&profiles);
+  CodeEntry* entry1 = generator.NewCodeEntry(i::Logger::FUNCTION_TAG, "aaa");
+  CodeEntry* entry2 = generator.NewCodeEntry(i::Logger::FUNCTION_TAG, "bbb");
+  CodeEntry* entry3 = generator.NewCodeEntry(i::Logger::FUNCTION_TAG, "ccc");
+  generator.code_map()->AddCode(ToAddress(0x1500), entry1, 0x200);
+  generator.code_map()->AddCode(ToAddress(0x1700), entry2, 0x100);
+  generator.code_map()->AddCode(ToAddress(0x1900), entry3, 0x50);
+
+  // We are building the following calls tree:
+  //      -> aaa         - sample1
+  //  aaa -> bbb -> ccc  - sample2
+  //      -> ccc -> aaa  - sample3
+  TickSample sample1;
+  sample1.pc = ToAddress(0x1600);
+  sample1.function = ToAddress(0x1500);
+  sample1.stack[0] = ToAddress(0x1510);
+  sample1.frames_count = 1;
+  generator.RecordTickSample(sample1);
+  TickSample sample2;
+  sample2.pc = ToAddress(0x1925);
+  sample2.function = ToAddress(0x1900);
+  sample2.stack[0] = ToAddress(0x1780);
+  sample2.stack[1] = ToAddress(0x10000);  // non-existent.
+  sample2.stack[2] = ToAddress(0x1620);
+  sample2.frames_count = 3;
+  generator.RecordTickSample(sample2);
+  TickSample sample3;
+  sample3.pc = ToAddress(0x1510);
+  sample3.function = ToAddress(0x1500);
+  sample3.stack[0] = ToAddress(0x1910);
+  sample3.stack[1] = ToAddress(0x1610);
+  sample3.frames_count = 2;
+  generator.RecordTickSample(sample3);
+
+  CpuProfile* profile = profiles.StopProfiling("", 1);
+  CHECK_NE(NULL, profile);
+  ProfileTreeTestHelper top_down_test_helper(profile->top_down());
+  CHECK_EQ(NULL, top_down_test_helper.Walk(entry2));
+  CHECK_EQ(NULL, top_down_test_helper.Walk(entry3));
+  ProfileNode* node1 = top_down_test_helper.Walk(entry1);
+  CHECK_NE(NULL, node1);
+  CHECK_EQ(entry1, node1->entry());
+  ProfileNode* node2 = top_down_test_helper.Walk(entry1, entry1);
+  CHECK_NE(NULL, node2);
+  CHECK_EQ(entry1, node2->entry());
+  ProfileNode* node3 = top_down_test_helper.Walk(entry1, entry2, entry3);
+  CHECK_NE(NULL, node3);
+  CHECK_EQ(entry3, node3->entry());
+  ProfileNode* node4 = top_down_test_helper.Walk(entry1, entry3, entry1);
+  CHECK_NE(NULL, node4);
+  CHECK_EQ(entry1, node4->entry());
+}
+
+
+TEST(SampleRateCalculator) {
+  const double kSamplingIntervalMs = i::Logger::kSamplingIntervalMs;
+
+  // Verify that ticking exactly in query intervals results in the
+  // initial sampling interval.
+  double time = 0.0;
+  SampleRateCalculator calc1;
+  CHECK_EQ(kSamplingIntervalMs, calc1.ticks_per_ms());
+  calc1.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc1.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs;
+  calc1.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc1.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs;
+  calc1.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc1.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs;
+  calc1.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc1.ticks_per_ms());
+
+  SampleRateCalculator calc2;
+  time = 0.0;
+  CHECK_EQ(kSamplingIntervalMs, calc2.ticks_per_ms());
+  calc2.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc2.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs * 0.5;
+  calc2.UpdateMeasurements(time);
+  // (1.0 + 2.0) / 2
+  CHECK_EQ(kSamplingIntervalMs * 1.5, calc2.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs * 0.75;
+  calc2.UpdateMeasurements(time);
+  // (1.0 + 2.0 + 2.0) / 3
+  CHECK_EQ(kSamplingIntervalMs * 1.66666, calc2.ticks_per_ms());
+
+  SampleRateCalculator calc3;
+  time = 0.0;
+  CHECK_EQ(kSamplingIntervalMs, calc3.ticks_per_ms());
+  calc3.UpdateMeasurements(time);
+  CHECK_EQ(kSamplingIntervalMs, calc3.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs * 2;
+  calc3.UpdateMeasurements(time);
+  // (1.0 + 0.5) / 2
+  CHECK_EQ(kSamplingIntervalMs * 0.75, calc3.ticks_per_ms());
+  time += SampleRateCalculator::kWallTimeQueryIntervalMs * 1.5;
+  calc3.UpdateMeasurements(time);
+  // (1.0 + 0.5 + 0.5) / 3
+  CHECK_EQ(kSamplingIntervalMs * 0.66666, calc3.ticks_per_ms());
+}
+
+#endif  // ENABLE_LOGGING_AND_PROFILING