Debugger: require debugger to be active when dealing with breaks.

This invariant will save us some head ache.
The changes to test-debug/DebugStub is due to the fact that it abuses
the ability to set break points in code that has no debug break slots.
This is now no longer possible.

R=ulan@chromium.org
BUG=v8:4132
LOG=N

Review URL: https://codereview.chromium.org/1181013007

Cr-Commit-Position: refs/heads/master@{#29038}

src/debug.cc

@@ -58,6 +58,23 @@ static v8::Handle<v8::Context> GetDebugEventContext(Isolate* isolate) {
 }
 
 
+BreakLocation::BreakLocation(Handle<DebugInfo> debug_info, RelocInfo* rinfo,
+                             RelocInfo* original_rinfo, int position,
+                             int statement_position)
+    : debug_info_(debug_info),
+      pc_offset_(static_cast<int>(rinfo->pc() - debug_info->code()->entry())),
+      original_pc_offset_(static_cast<int>(
+          original_rinfo->pc() - debug_info->original_code()->entry())),
+      rmode_(rinfo->rmode()),
+      original_rmode_(original_rinfo->rmode()),
+      data_(rinfo->data()),
+      original_data_(original_rinfo->data()),
+      position_(position),
+      statement_position_(statement_position) {
+  DCHECK(debug_info_->GetIsolate()->debug()->is_active());
+}
+
+
 BreakLocation::Iterator::Iterator(Handle<DebugInfo> debug_info,
                                   BreakLocatorType type)
     : debug_info_(debug_info),
@@ -503,6 +520,8 @@ ScriptCache::ScriptCache(Isolate* isolate) : isolate_(isolate) {
   Heap* heap = isolate_->heap();
   HandleScope scope(isolate_);
 
+  DCHECK(isolate_->debug()->is_active());
+
   // Perform a GC to get rid of all unreferenced scripts.
   heap->CollectAllGarbage(Heap::kMakeHeapIterableMask, "ScriptCache");
 
@@ -2941,16 +2960,17 @@ void Debug::SetMessageHandler(v8::Debug::MessageHandler handler) {
 
 
 void Debug::UpdateState() {
-  is_active_ = message_handler_ != NULL || !event_listener_.is_null();
-  if (is_active_ || in_debug_scope()) {
+  bool is_active = message_handler_ != NULL || !event_listener_.is_null();
+  if (is_active || in_debug_scope()) {
     // Note that the debug context could have already been loaded to
     // bootstrap test cases.
     isolate_->compilation_cache()->Disable();
-    is_active_ = Load();
+    is_active = Load();
   } else if (is_loaded()) {
     isolate_->compilation_cache()->Enable();
     Unload();
   }
+  is_active_ = is_active;
 }
 
 

src/debug.h

@@ -129,17 +129,8 @@ class BreakLocation {
 
  private:
   BreakLocation(Handle<DebugInfo> debug_info, RelocInfo* rinfo,
-                RelocInfo* original_rinfo, int position, int statement_position)
-      : debug_info_(debug_info),
-        pc_offset_(static_cast<int>(rinfo->pc() - debug_info->code()->entry())),
-        original_pc_offset_(static_cast<int>(
-            original_rinfo->pc() - debug_info->original_code()->entry())),
-        rmode_(rinfo->rmode()),
-        original_rmode_(original_rinfo->rmode()),
-        data_(rinfo->data()),
-        original_data_(original_rinfo->data()),
-        position_(position),
-        statement_position_(statement_position) {}
+                RelocInfo* original_rinfo, int position,
+                int statement_position);
 
   class Iterator {
    public:
@@ -526,7 +517,8 @@ class Debug {
   static void RecordEvalCaller(Handle<Script> script);
 
   bool CheckExecutionState(int id) {
-    return !debug_context().is_null() && break_id() != 0 && break_id() == id;
+    return is_active() && !debug_context().is_null() && break_id() != 0 &&
+           break_id() == id;
   }
 
   // Flags and states.

src/runtime/runtime-debug.cc

@@ -2183,7 +2183,7 @@ static bool IsPositionAlignmentCodeCorrect(int alignment) {
 RUNTIME_FUNCTION(Runtime_GetBreakLocations) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
-
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, fun, 0);
   CONVERT_NUMBER_CHECKED(int32_t, statement_aligned_code, Int32, args[1]);
 
@@ -2211,6 +2211,7 @@ RUNTIME_FUNCTION(Runtime_GetBreakLocations) {
 RUNTIME_FUNCTION(Runtime_SetFunctionBreakPoint) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 3);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
   CONVERT_NUMBER_CHECKED(int32_t, source_position, Int32, args[1]);
   RUNTIME_ASSERT(source_position >= function->shared()->start_position() &&
@@ -2235,6 +2236,7 @@ RUNTIME_FUNCTION(Runtime_SetFunctionBreakPoint) {
 RUNTIME_FUNCTION(Runtime_SetScriptBreakPoint) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 4);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(JSValue, wrapper, 0);
   CONVERT_NUMBER_CHECKED(int32_t, source_position, Int32, args[1]);
   RUNTIME_ASSERT(source_position >= 0);
@@ -2266,6 +2268,7 @@ RUNTIME_FUNCTION(Runtime_SetScriptBreakPoint) {
 RUNTIME_FUNCTION(Runtime_ClearBreakPoint) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(Object, break_point_object_arg, 0);
 
   // Clear break point.
@@ -2363,6 +2366,7 @@ RUNTIME_FUNCTION(Runtime_PrepareStep) {
 RUNTIME_FUNCTION(Runtime_ClearStepping) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 0);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   isolate->debug()->ClearStepping();
   return isolate->heap()->undefined_value();
 }
@@ -2709,6 +2713,7 @@ RUNTIME_FUNCTION(Runtime_DebugEvaluateGlobal) {
 RUNTIME_FUNCTION(Runtime_DebugGetLoadedScripts) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 0);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
 
   Handle<FixedArray> instances;
   {
@@ -2976,6 +2981,7 @@ RUNTIME_FUNCTION(Runtime_GetFunctionCodePositionFromSource) {
   HandleScope scope(isolate);
   CHECK(isolate->debug()->live_edit_enabled());
   DCHECK(args.length() == 2);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
   CONVERT_NUMBER_CHECKED(int32_t, source_position, Int32, args[1]);
 
@@ -3117,6 +3123,8 @@ RUNTIME_FUNCTION(Runtime_DebugCallbackSupportsStepping) {
 // built-in function such as Array.forEach to enable stepping into the callback.
 RUNTIME_FUNCTION(Runtime_DebugPrepareStepInIfStepping) {
   DCHECK(args.length() == 1);
+  RUNTIME_ASSERT(isolate->debug()->is_active());
+
   Debug* debug = isolate->debug();
   if (!debug->IsStepping()) return isolate->heap()->undefined_value();
 

test/cctest/cctest.h

@@ -575,6 +575,18 @@ static inline void SimulateIncrementalMarking(i::Heap* heap) {
 }
 
 
+static void DummyDebugEventListener(
+    const v8::Debug::EventDetails& event_details) {}
+
+
+static inline void EnableDebugger() {
+  v8::Debug::SetDebugEventListener(&DummyDebugEventListener);
+}
+
+
+static inline void DisableDebugger() { v8::Debug::SetDebugEventListener(NULL); }
+
+
 // Helper class for new allocations tracking and checking.
 // To use checking of JS allocations tracking in a test,
 // just create an instance of this class.

test/cctest/test-api.cc

@@ -20960,6 +20960,7 @@ TEST(StreamingWithDebuggingDoesNotProduceParserCache) {
   CompileRun("function break_here() { }");
   i::Handle<i::JSFunction> func = i::Handle<i::JSFunction>::cast(
       v8::Utils::OpenHandle(*env->Global()->Get(v8_str("break_here"))));
+  EnableDebugger();
   v8::internal::Debug* debug = CcTest::i_isolate()->debug();
   int position = 0;
   debug->SetBreakPoint(func, i::Handle<i::Object>(v8::internal::Smi::FromInt(1),
@@ -20980,6 +20981,7 @@ TEST(StreamingWithDebuggingDoesNotProduceParserCache) {
 
   // Check that we got no cached data.
   CHECK(source.GetCachedData() == NULL);
+  DisableDebugger();
 }
 
 

test/cctest/test-debug.cc

@@ -445,6 +445,7 @@ void CheckDebugBreakFunction(DebugLocalContext* env,
                              const char* source, const char* name,
                              int position, v8::internal::RelocInfo::Mode mode,
                              Code* debug_break) {
+  EnableDebugger();
   i::Debug* debug = CcTest::i_isolate()->debug();
 
   // Create function and set the break point.
@@ -488,6 +489,8 @@ void CheckDebugBreakFunction(DebugLocalContext* env,
     i::RelocInfo rinfo = location.rinfo();
     CHECK(!rinfo.IsPatchedReturnSequence());
   }
+
+  DisableDebugger();
 }
 
 
@@ -986,12 +989,10 @@ TEST(DebugStub) {
                           v8::internal::RelocInfo::CODE_TARGET,
                           CcTest::i_isolate()->builtins()->builtin(
                               Builtins::kStoreIC_DebugBreak));
-  CheckDebugBreakFunction(&env,
-                          "function f3(){var a=x;}", "f3",
-                          0,
-                          v8::internal::RelocInfo::CODE_TARGET,
-                          CcTest::i_isolate()->builtins()->builtin(
-                              Builtins::kLoadIC_DebugBreak));
+  CheckDebugBreakFunction(
+      &env, "function f3(){x();}", "f3", 0,
+      v8::internal::RelocInfo::CODE_TARGET,
+      CcTest::i_isolate()->builtins()->builtin(Builtins::kLoadIC_DebugBreak));
 
 // TODO(1240753): Make the test architecture independent or split
 // parts of the debugger into architecture dependent files. This
@@ -1001,29 +1002,21 @@ TEST(DebugStub) {
   CheckDebugBreakFunction(
       &env,
       "function f4(){var index='propertyName'; var a={}; a[index] = 'x';}",
-      "f4",
-      0,
-      v8::internal::RelocInfo::CODE_TARGET,
+      "f4", 39, v8::internal::RelocInfo::CODE_TARGET,
       CcTest::i_isolate()->builtins()->builtin(
           Builtins::kKeyedStoreIC_DebugBreak));
   CheckDebugBreakFunction(
       &env,
       "function f5(){var index='propertyName'; var a={}; return a[index];}",
-      "f5",
-      0,
-      v8::internal::RelocInfo::CODE_TARGET,
+      "f5", 39, v8::internal::RelocInfo::CODE_TARGET,
       CcTest::i_isolate()->builtins()->builtin(
           Builtins::kKeyedLoadIC_DebugBreak));
 #endif
 
-  CheckDebugBreakFunction(
-      &env,
-      "function f6(a){return a==null;}",
-      "f6",
-      0,
-      v8::internal::RelocInfo::CODE_TARGET,
-      CcTest::i_isolate()->builtins()->builtin(
-          Builtins::kCompareNilIC_DebugBreak));
+  CheckDebugBreakFunction(&env, "function f6(){(0==null)()}", "f6", 0,
+                          v8::internal::RelocInfo::CODE_TARGET,
+                          CcTest::i_isolate()->builtins()->builtin(
+                              Builtins::kCompareNilIC_DebugBreak));
 
   // Check the debug break code stubs for call ICs with different number of
   // parameters.
@@ -1066,6 +1059,7 @@ TEST(DebugInfo) {
   CHECK_EQ(0, v8::internal::GetDebuggedFunctions()->length());
   CHECK(!HasDebugInfo(foo));
   CHECK(!HasDebugInfo(bar));
+  EnableDebugger();
   // One function (foo) is debugged.
   int bp1 = SetBreakPoint(foo, 0);
   CHECK_EQ(1, v8::internal::GetDebuggedFunctions()->length());
@@ -1083,6 +1077,7 @@ TEST(DebugInfo) {
   CHECK(HasDebugInfo(bar));
   // No functions are debugged.
   ClearBreakPoint(bp2);
+  DisableDebugger();
   CHECK_EQ(0, v8::internal::GetDebuggedFunctions()->length());
   CHECK(!HasDebugInfo(foo));
   CHECK(!HasDebugInfo(bar));
@@ -2290,11 +2285,12 @@ TEST(RemoveBreakPointInBreak) {
 
   v8::Local<v8::Function> foo =
       CompileFunction(&env, "function foo(){a=1;}", "foo");
-  debug_event_remove_break_point = SetBreakPoint(foo, 0);
 
   // Register the debug event listener pasing the function
   v8::Debug::SetDebugEventListener(DebugEventRemoveBreakPoint, foo);
 
+  debug_event_remove_break_point = SetBreakPoint(foo, 0);
+
   break_point_hit_count = 0;
   foo->Call(env->Global(), 0, NULL);
   CHECK_EQ(1, break_point_hit_count);
@@ -2781,11 +2777,11 @@ TEST(DebugStepLinear) {
   // Run foo to allow it to get optimized.
   CompileRun("a=0; b=0; c=0; foo();");
 
-  SetBreakPoint(foo, 3);
-
   // Register a debug event listener which steps and counts.
   v8::Debug::SetDebugEventListener(DebugEventStep);
 
+  SetBreakPoint(foo, 3);
+
   step_action = StepIn;
   break_point_hit_count = 0;
   foo->Call(env->Global(), 0, NULL);
@@ -5579,11 +5575,6 @@ TEST(RecursiveBreakpointsGlobal) {
 }
 
 
-static void DummyDebugEventListener(
-    const v8::Debug::EventDetails& event_details) {
-}
-
-
 TEST(SetDebugEventListenerOnUninitializedVM) {
   v8::Debug::SetDebugEventListener(DummyDebugEventListener);
 }
@@ -5957,7 +5948,7 @@ TEST(DebugGetLoadedScripts) {
       v8::String::NewExternal(env->GetIsolate(), &source_ext_str);
   v8::Handle<v8::Script> evil_script(v8::Script::Compile(source));
   // "use" evil_script to make the compiler happy.
-  (void) evil_script;
+  USE(evil_script);
   Handle<i::ExternalTwoByteString> i_source(
       i::ExternalTwoByteString::cast(*v8::Utils::OpenHandle(*source)));
   // This situation can happen if source was an external string disposed
@@ -5966,12 +5957,14 @@ TEST(DebugGetLoadedScripts) {
 
   bool allow_natives_syntax = i::FLAG_allow_natives_syntax;
   i::FLAG_allow_natives_syntax = true;
+  EnableDebugger();
   CompileRun(
       "var scripts = %DebugGetLoadedScripts();"
       "var count = scripts.length;"
       "for (var i = 0; i < count; ++i) {"
       "  scripts[i].line_ends;"
       "}");
+  DisableDebugger();
   // Must not crash while accessing line_ends.
   i::FLAG_allow_natives_syntax = allow_natives_syntax;
 
@@ -6539,6 +6532,8 @@ TEST(ProvisionalBreakpointOnLineOutOfRange) {
   const char* script = "function f() {};";
   const char* resource_name = "test_resource";
 
+  v8::Debug::SetMessageHandler(AfterCompileMessageHandler);
+
   // Set a couple of provisional breakpoint on lines out of the script lines
   // range.
   int sbp1 = SetScriptBreakPointByNameFromJS(env->GetIsolate(), resource_name,
@@ -6547,7 +6542,6 @@ TEST(ProvisionalBreakpointOnLineOutOfRange) {
       SetScriptBreakPointByNameFromJS(env->GetIsolate(), resource_name, 5, 5);
 
   after_compile_message_count = 0;
-  v8::Debug::SetMessageHandler(AfterCompileMessageHandler);
 
   v8::ScriptOrigin origin(
       v8::String::NewFromUtf8(env->GetIsolate(), resource_name),

test/cctest/test-heap.cc

@@ -1382,8 +1382,10 @@ TEST(TestCodeFlushingIncrementalAbort) {
   // disabled.
   int position = 0;
   Handle<Object> breakpoint_object(Smi::FromInt(0), isolate);
+  EnableDebugger();
   isolate->debug()->SetBreakPoint(function, breakpoint_object, &position);
   isolate->debug()->ClearAllBreakPoints();
+  DisableDebugger();
 
   // Force optimization now that code flushing is disabled.
   { v8::HandleScope scope(CcTest::isolate());

test/mjsunit/debug-liveedit-breakpoints.js

@@ -29,6 +29,7 @@
 // Get the Debug object exposed from the debug context global object.
 
 Debug = debug.Debug
+Debug.setListener(function(){});
 
 var function_z_text =
 "  function Z() {\n"
@@ -111,3 +112,4 @@ for (var i = 0; i < breaks_ids.length; i++) {
 }
 
 assertEquals(0, Debug.scriptBreakPoints().length);
+Debug.setListener(null);

test/mjsunit/debug-liveedit-patch-positions.js

@@ -33,6 +33,7 @@
 // corresponding byte-code PCs should coincide before change and after it.
 
 Debug = debug.Debug
+Debug.setListener(function() {});
 
 eval(
     "function F1() {  return 5; }\n" +
@@ -124,3 +125,5 @@ print(pcArray2);
 if (pcArray1 && pcArray2) {
   assertArrayEquals(pcArray1, pcArray2);
 }
+
+Debug.setListener(null);

test/mjsunit/debug-liveedit-stack-padding.js

@@ -29,6 +29,7 @@
 // Get the Debug object exposed from the debug context global object.
 
 Debug = debug.Debug;
+Debug.setListener(listener);
 
 SlimFunction = eval(
     "(function() {\n " +
@@ -76,7 +77,6 @@ function listener(event, exec_state, event_data, data) {
   }
 }
 
-Debug.setListener(listener);
 
 var animal = SlimFunction();
 
@@ -86,3 +86,5 @@ if (saved_exception) {
 }
 
 assertEquals("Capybara", animal);
+
+Debug.setListener(null);

test/mjsunit/debug-script-breakpoints.js

@@ -28,6 +28,7 @@
 // Flags: --expose-debug-as debug
 // Get the Debug object exposed from the debug context global object.
 Debug = debug.Debug
+Debug.setListener(function(){});
 
 // Set and remove a script break point for a named script.
 var sbp = Debug.setScriptBreakPointByName("1", 2, 3);
@@ -110,3 +111,5 @@ Debug.clearBreakPoint(sbp3);
 assertEquals(1, Debug.scriptBreakPoints().length);
 Debug.clearBreakPoint(sbp2);
 assertEquals(0, Debug.scriptBreakPoints().length);
+
+Debug.setListener(null);

test/mjsunit/debug-script.js

@@ -36,6 +36,7 @@
 
 // Get the Debug object exposed from the debug context global object.
 Debug = debug.Debug;
+Debug.setListener(function(){});
 
 Date();
 RegExp();
@@ -103,3 +104,5 @@ assertEquals(Debug.ScriptType.Normal, debug_script.type);
 // Check a nonexistent script.
 var dummy_script = Debug.findScript('dummy.js');
 assertTrue(typeof dummy_script == 'undefined');
+
+Debug.setListener(null);

test/mjsunit/debug-stepin-positions.js

@@ -33,7 +33,7 @@ function DebuggerStatement() {
   debugger;  /*pause*/
 }
 
-function TestCase(fun, frame_number) {
+function TestCase(fun, frame_number, line_number) {
   var exception = false;
   var codeSnippet = undefined;
   var resultPositions = undefined;
@@ -64,8 +64,13 @@ function TestCase(fun, frame_number) {
 
   Debug.setListener(listener);
 
+  var breakpointId;
+  if (line_number) breakpointId = Debug.setBreakPoint(fun, line_number);
+
   fun();
 
+  if (line_number) Debug.clearBreakPoint(breakpointId);
+
   Debug.setListener(null);
 
   assertTrue(!exception, exception);
@@ -116,9 +121,7 @@ function TestCaseWithDebugger(fun) {
 }
 
 function TestCaseWithBreakpoint(fun, line_number, frame_number) {
-  var breakpointId = Debug.setBreakPoint(fun, line_number);
-  TestCase(fun, frame_number);
-  Debug.clearBreakPoint(breakpointId);
+  TestCase(fun, frame_number, line_number);
 }
 
 function TestCaseWithException(fun, frame_number) {

test/mjsunit/deserialize-script-id.js

@@ -5,6 +5,9 @@
 // Flags: --allow-natives-syntax --cache=code
 // Test that script ids are unique and we found the correct ones.
 
+var Debug = %GetDebugContext().Debug;
+Debug.setListener(function(){});
+
 var scripts = %DebugGetLoadedScripts();
 scripts.sort(function(a, b) { return a.id - b.id; });
 var user_script_count = 0;
@@ -15,3 +18,5 @@ scripts.reduce(function(prev, cur) {
 
 // Found mjsunit.js and this script.
 assertEquals(2, user_script_count);
+
+Debug.setListener(null);

test/mjsunit/es6/debug-evaluate-blockscopes.js

@@ -48,8 +48,6 @@ function f() {
 
 // Get the Debug object exposed from the debug context global object.
 var Debug = debug.Debug
-// Set breakpoint on line 6.
-var bp = Debug.setBreakPoint(f, 6);
 
 function listener(event, exec_state, event_data, data) {
   if (event == Debug.DebugEvent.Break) {
@@ -59,6 +57,10 @@ function listener(event, exec_state, event_data, data) {
 
 // Add the debug event listener.
 Debug.setListener(listener);
+
+//Set breakpoint on line 6.
+var bp = Debug.setBreakPoint(f, 6);
+
 result = -1;
 f();
 assertEquals(1, result);
@@ -107,3 +109,5 @@ assertEquals(null, exception, exception);
 exception = null;
 f2();
 assertEquals(null, exception, exception);
+
+Debug.setListener(null);

test/mjsunit/es6/generators-relocation.js

@@ -25,13 +25,13 @@ function RunTest(formals_and_body, args, value1, value2) {
   // Advance to the first yield.
   assertIteratorResult(value1, false, obj.next());
 
-  // Add a breakpoint on line 3 (the second yield).
-  var bp = Debug.setBreakPoint(gen, 3);
-
   // Enable the debugger, which should force recompilation of the generator
   // function and relocation of the suspended generator activation.
   Debug.setListener(listener);
 
+  // Add a breakpoint on line 3 (the second yield).
+  var bp = Debug.setBreakPoint(gen, 3);
+
   // Check that the generator resumes and suspends properly.
   assertIteratorResult(value2, false, obj.next());
 

test/mjsunit/regress/regress-1586.js

@@ -43,8 +43,6 @@ function f() {
 
 // Get the Debug object exposed from the debug context global object.
 Debug = debug.Debug
-// Set breakpoint on line 6.
-var bp = Debug.setBreakPoint(f, 6);
 
 function listener(event, exec_state, event_data, data) {
   if (event == Debug.DebugEvent.Break) {
@@ -54,6 +52,10 @@ function listener(event, exec_state, event_data, data) {
 
 // Add the debug event listener.
 Debug.setListener(listener);
+
+//Set breakpoint on line 6.
+var bp = Debug.setBreakPoint(f, 6);
+
 result = -1;
 f();
 assertEquals(1, result);

test/mjsunit/regress/regress-2318.js

@@ -56,11 +56,12 @@ function f() {
 };
 
 Debug = debug.Debug;
-var bp = Debug.setBreakPoint(f, 0);
 
 function listener(event, exec_state, event_data, data) {
   result = exec_state.frame().evaluate("i").value();
 };
 
 Debug.setListener(listener);
+var bp = Debug.setBreakPoint(f, 0);
+
 assertThrows(function() { f(); }, RangeError);

test/mjsunit/regress/regress-crbug-424142.js

@@ -23,6 +23,7 @@
 function sentinel() {}
 
 Debug = debug.Debug;
+Debug.setListener(function(){});
 
 var script = Debug.findScript(sentinel);
 var line = 14;
@@ -34,3 +35,5 @@ var actual = Debug.setBreakPointByScriptIdAndPosition(
 // the break point.
 assertTrue(line_start <= actual);
 assertTrue(actual <= line_end);
+
+Debug.setListener(null);

test/mjsunit/regress/regress-crbug-474297.js

@@ -4,4 +4,9 @@
 
 // Flags: --gc-interval=33 --expose-gc --allow-natives-syntax
 
+var Debug = %GetDebugContext().Debug;
+Debug.setListener(function(){});
+
 %DebugGetLoadedScripts();
+
+Debug.setListener(null);

test/mjsunit/regress/regress-debug-code-recompilation.js

@@ -29,6 +29,7 @@
 // Flags: --expose-debug-as debug
 
 Debug = debug.Debug
+Debug.setListener(function(){});
 
 function f() {a=1;b=2};
 function g() {
@@ -46,3 +47,5 @@ Debug.clearBreakPoint(bp);
 %OptimizeFunctionOnNextCall(Debug.setBreakPoint);
 bp = Debug.setBreakPoint(f, 0, 0);
 Debug.clearBreakPoint(bp);
+
+Debug.setListener(null);

test/mjsunit/regress/regress-prepare-break-while-recompile.js

@@ -54,8 +54,10 @@ foo();
 // and (shared) unoptimized code on foo, and sets both to lazy-compile builtin.
 // Clear the break point immediately after to deactivate the debugger.
 // Do all of this after compile graph has been created.
+Debug.setListener(function(){});
 Debug.setBreakPoint(bar, 0, 0);
 Debug.clearAllBreakPoints();
+Debug.setListener(null);
 
 // At this point, concurrent recompilation is still blocked.
 assertUnoptimized(foo, "no sync");