Disable other background modules while testing the CompilerDispatcher

R=rmcilroy@chromium.org,mlippautz@chromium.org
BUG=v8:6069

Change-Id: Iea0134ef3a0252f5a6f4ae2154218776dc6ff96d
Reviewed-on: https://chromium-review.googlesource.com/453960
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43786}

src/compiler-dispatcher/compiler-dispatcher.cc

@@ -562,7 +562,6 @@ void CompilerDispatcher::ConsiderJobForBackgroundProcessing(
 void CompilerDispatcher::ScheduleMoreBackgroundTasksIfNeeded() {
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"),
                "V8.CompilerDispatcherScheduleMoreBackgroundTasksIfNeeded");
-  if (FLAG_single_threaded) return;
   {
     base::LockGuard<base::Mutex> lock(&mutex_);
     if (pending_background_jobs_.empty()) return;

src/flag-definitions.h

@@ -1282,6 +1282,7 @@ DEFINE_NEG_IMPLICATION(single_threaded, concurrent_recompilation)
 DEFINE_NEG_IMPLICATION(single_threaded, concurrent_sweeping)
 DEFINE_NEG_IMPLICATION(single_threaded, parallel_compaction)
 DEFINE_NEG_IMPLICATION(single_threaded, concurrent_store_buffer)
+DEFINE_NEG_IMPLICATION(single_threaded, compiler_dispatcher)
 
 #undef FLAG
 

src/flags.h

@@ -15,7 +15,7 @@ namespace internal {
 #include "src/flag-definitions.h"  // NOLINT
 
 // The global list of all flags.
-class FlagList {
+class V8_EXPORT_PRIVATE FlagList {
  public:
   // The list of all flags with a value different from the default
   // and their values. The format of the list is like the format of the

test/unittests/compiler-dispatcher/compiler-dispatcher-job-unittest.cc

@@ -30,24 +30,27 @@ class CompilerDispatcherJobTest : public TestWithContext {
   CompilerDispatcherTracer* tracer() { return &tracer_; }
 
   static void SetUpTestCase() {
-    old_flag_ = i::FLAG_ignition;
-    i::FLAG_ignition = true;
+    CHECK_NULL(save_flags_);
+    save_flags_ = new SaveFlags();
+    FLAG_ignition = true;
     TestWithContext::SetUpTestCase();
   }
 
   static void TearDownTestCase() {
     TestWithContext::TearDownTestCase();
-    i::FLAG_ignition = old_flag_;
+    CHECK_NOT_NULL(save_flags_);
+    delete save_flags_;
+    save_flags_ = nullptr;
   }
 
  private:
   CompilerDispatcherTracer tracer_;
-  static bool old_flag_;
+  static SaveFlags* save_flags_;
 
   DISALLOW_COPY_AND_ASSIGN(CompilerDispatcherJobTest);
 };
 
-bool CompilerDispatcherJobTest::old_flag_;
+SaveFlags* CompilerDispatcherJobTest::save_flags_ = nullptr;
 
 namespace {
 

test/unittests/compiler-dispatcher/compiler-dispatcher-unittest.cc

@@ -26,26 +26,27 @@ namespace internal {
 class CompilerDispatcherTestFlags {
  public:
   static void SetFlagsForTest() {
-    old_compiler_dispatcher_flag_ = i::FLAG_compiler_dispatcher;
-    i::FLAG_compiler_dispatcher = true;
-    old_ignition_flag_ = i::FLAG_ignition;
-    i::FLAG_ignition = true;
+    CHECK_NULL(save_flags_);
+    save_flags_ = new SaveFlags();
+    FLAG_single_threaded = true;
+    FLAG_ignition = true;
+    FlagList::EnforceFlagImplications();
+    FLAG_compiler_dispatcher = true;
   }
 
   static void RestoreFlags() {
-    i::FLAG_compiler_dispatcher = old_compiler_dispatcher_flag_;
-    i::FLAG_ignition = old_ignition_flag_;
+    CHECK_NOT_NULL(save_flags_);
+    delete save_flags_;
+    save_flags_ = nullptr;
   }
 
  private:
-  static bool old_compiler_dispatcher_flag_;
-  static bool old_ignition_flag_;
+  static SaveFlags* save_flags_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompilerDispatcherTestFlags);
 };
 
-bool CompilerDispatcherTestFlags::old_compiler_dispatcher_flag_;
-bool CompilerDispatcherTestFlags::old_ignition_flag_;
+SaveFlags* CompilerDispatcherTestFlags::save_flags_ = nullptr;
 
 class CompilerDispatcherTest : public TestWithContext {
  public:

test/unittests/test-utils.cc

@@ -8,6 +8,7 @@
 #include "src/base/platform/time.h"
 #include "src/flags.h"
 #include "src/isolate.h"
+#include "src/list-inl.h"
 #include "src/objects-inl.h"
 #include "src/v8.h"
 
@@ -96,5 +97,20 @@ Handle<Context> TestWithNativeContext::native_context() const {
   return isolate()->native_context();
 }
 
+SaveFlags::SaveFlags() { non_default_flags_ = FlagList::argv(); }
+
+SaveFlags::~SaveFlags() {
+  FlagList::ResetAllFlags();
+  int argc = non_default_flags_->length();
+  FlagList::SetFlagsFromCommandLine(
+      &argc, const_cast<char**>(non_default_flags_->begin()),
+      false /* remove_flags */);
+  for (auto flag = non_default_flags_->begin();
+       flag != non_default_flags_->end(); ++flag) {
+    delete[] * flag;
+  }
+  delete non_default_flags_;
+}
+
 }  // namespace internal
 }  // namespace v8

test/unittests/test-utils.h

@@ -8,6 +8,7 @@
 #include "include/v8.h"
 #include "src/base/macros.h"
 #include "src/base/utils/random-number-generator.h"
+#include "src/list.h"
 #include "src/zone/accounting-allocator.h"
 #include "src/zone/zone.h"
 #include "testing/gtest-support.h"
@@ -135,6 +136,17 @@ class TestWithNativeContext : public virtual ::v8::TestWithContext,
   DISALLOW_COPY_AND_ASSIGN(TestWithNativeContext);
 };
 
+class SaveFlags {
+ public:
+  SaveFlags();
+  ~SaveFlags();
+
+ private:
+  List<const char*>* non_default_flags_;
+
+  DISALLOW_COPY_AND_ASSIGN(SaveFlags);
+};
+
 }  // namespace internal
 }  // namespace v8