deps: update V8 to 6.9.427.22

PR-URL: https://github.com/nodejs/node/pull/21983
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Ujjwal Sharma <usharma1998@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

1 files changed, 136 insertions, 1165 deletions

diff --git a/deps/v8/src/runtime/runtime-debug.cc b/deps/v8/src/runtime/runtime-debug.cc
index fabb1a80da..9711ffad54 100644
--- a/deps/v8/src/runtime/runtime-debug.cc
+++ b/deps/v8/src/runtime/runtime-debug.cc
@@ -21,6 +21,8 @@
 #include "src/interpreter/interpreter.h"
 #include "src/isolate-inl.h"
 #include "src/objects/debug-objects-inl.h"
+#include "src/objects/js-collection-inl.h"
+#include "src/objects/js-promise-inl.h"
 #include "src/runtime/runtime.h"
 #include "src/snapshot/snapshot.h"
 #include "src/wasm/wasm-objects-inl.h"
@@ -45,7 +47,8 @@ RUNTIME_FUNCTION_RETURN_PAIR(Runtime_DebugBreakOnBytecode) {
   // Get the top-most JavaScript frame.
   JavaScriptFrameIterator it(isolate);
   if (isolate->debug_execution_mode() == DebugInfo::kBreakpoints) {
-    isolate->debug()->Break(it.frame(), handle(it.frame()->function()));
+    isolate->debug()->Break(it.frame(),
+                            handle(it.frame()->function(), isolate));
   }
 
   // Return the handler from the original bytecode array.
@@ -81,7 +84,7 @@ RUNTIME_FUNCTION_RETURN_PAIR(Runtime_DebugBreakOnBytecode) {
                                                                 operand_scale);
 
   if (side_effect_check_failed) {
-    return MakePair(isolate->heap()->exception(),
+    return MakePair(ReadOnlyRoots(isolate).exception(),
                     Smi::FromInt(static_cast<uint8_t>(bytecode)));
   }
   Object* interrupt_object = isolate->stack_guard()->HandleInterrupts();
@@ -107,15 +110,7 @@ RUNTIME_FUNCTION(Runtime_DebugBreakAtEntry) {
   DCHECK_EQ(*function, it.frame()->function());
   isolate->debug()->Break(it.frame(), function);
 
-  return isolate->heap()->undefined_value();
-}
-
-RUNTIME_FUNCTION(Runtime_DebugApplyInstrumentation) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
-  isolate->debug()->ApplyInstrumentation(handle(function->shared()));
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 RUNTIME_FUNCTION(Runtime_HandleDebuggerStatement) {
@@ -127,50 +122,13 @@ RUNTIME_FUNCTION(Runtime_HandleDebuggerStatement) {
   return isolate->stack_guard()->HandleInterrupts();
 }
 
-
 RUNTIME_FUNCTION(Runtime_ScheduleBreak) {
   SealHandleScope shs(isolate);
   DCHECK_EQ(0, args.length());
-  isolate->stack_guard()->RequestDebugBreak();
-  return isolate->heap()->undefined_value();
-}
-
-static Handle<Object> DebugGetProperty(LookupIterator* it,
-                                       bool* has_caught = nullptr) {
-  for (; it->IsFound(); it->Next()) {
-    switch (it->state()) {
-      case LookupIterator::NOT_FOUND:
-      case LookupIterator::TRANSITION:
-        UNREACHABLE();
-      case LookupIterator::ACCESS_CHECK:
-        // Ignore access checks.
-        break;
-      case LookupIterator::INTEGER_INDEXED_EXOTIC:
-      case LookupIterator::INTERCEPTOR:
-      case LookupIterator::JSPROXY:
-        return it->isolate()->factory()->undefined_value();
-      case LookupIterator::ACCESSOR: {
-        Handle<Object> accessors = it->GetAccessors();
-        if (!accessors->IsAccessorInfo()) {
-          return it->isolate()->factory()->undefined_value();
-        }
-        MaybeHandle<Object> maybe_result =
-            JSObject::GetPropertyWithAccessor(it);
-        Handle<Object> result;
-        if (!maybe_result.ToHandle(&result)) {
-          result = handle(it->isolate()->pending_exception(), it->isolate());
-          it->isolate()->clear_pending_exception();
-          if (has_caught != nullptr) *has_caught = true;
-        }
-        return result;
-      }
-
-      case LookupIterator::DATA:
-        return it->GetDataValue();
-    }
-  }
-
-  return it->isolate()->factory()->undefined_value();
+  isolate->RequestInterrupt(
+      [](v8::Isolate* isolate, void*) { v8::debug::BreakRightNow(isolate); },
+      nullptr);
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 template <class IteratorType>
@@ -288,7 +246,7 @@ MaybeHandle<JSArray> Runtime::GetInternalProperties(Isolate* isolate,
     result->set(1, *status_str);
 
     Handle<Object> value_obj(promise->status() == Promise::kPending
-                                 ? isolate->heap()->undefined_value()
+                                 ? ReadOnlyRoots(isolate).undefined_value()
                                  : promise->result(),
                              isolate);
     Handle<String> promise_value =
@@ -328,627 +286,6 @@ MaybeHandle<JSArray> Runtime::GetInternalProperties(Isolate* isolate,
   return factory->NewJSArray(0);
 }
 
-
-RUNTIME_FUNCTION(Runtime_DebugGetInternalProperties) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(Object, obj, 0);
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           Runtime::GetInternalProperties(isolate, obj));
-}
-
-
-// Get debugger related details for an object property, in the following format:
-// 0: Property value
-// 1: Property details
-// 2: Property value is exception
-// 3: Getter function if defined
-// 4: Setter function if defined
-// Items 2-4 are only filled if the property has either a getter or a setter.
-RUNTIME_FUNCTION(Runtime_DebugGetPropertyDetails) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
-  CONVERT_ARG_HANDLE_CHECKED(Object, name_obj, 1);
-
-  // Convert the {name_obj} to a Name.
-  Handle<Name> name;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, name,
-                                     Object::ToName(isolate, name_obj));
-
-  // Make sure to set the current context to the context before the debugger was
-  // entered (if the debugger is entered). The reason for switching context here
-  // is that for some property lookups (accessors and interceptors) callbacks
-  // into the embedding application can occur, and the embedding application
-  // could have the assumption that its own native context is the current
-  // context and not some internal debugger context.
-  SaveContext save(isolate);
-  if (isolate->debug()->in_debug_scope()) {
-    isolate->set_context(*isolate->debug()->debugger_entry()->GetContext());
-  }
-
-  // Check if the name is trivially convertible to an index and get the element
-  // if so.
-  uint32_t index;
-  // TODO(verwaest): Make sure DebugGetProperty can handle arrays, and remove
-  // this special case.
-  if (name->AsArrayIndex(&index)) {
-    Handle<FixedArray> details = isolate->factory()->NewFixedArray(2);
-    Handle<Object> element_or_char;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, element_or_char, JSReceiver::GetElement(isolate, obj, index));
-    details->set(0, *element_or_char);
-    details->set(1, PropertyDetails::Empty().AsSmi());
-    return *isolate->factory()->NewJSArrayWithElements(details);
-  }
-
-  LookupIterator it(obj, name, LookupIterator::OWN);
-  bool has_caught = false;
-  Handle<Object> value = DebugGetProperty(&it, &has_caught);
-  if (!it.IsFound()) return isolate->heap()->undefined_value();
-
-  Handle<Object> maybe_pair;
-  if (it.state() == LookupIterator::ACCESSOR) {
-    maybe_pair = it.GetAccessors();
-  }
-
-  // If the callback object is a fixed array then it contains JavaScript
-  // getter and/or setter.
-  bool has_js_accessors = !maybe_pair.is_null() && maybe_pair->IsAccessorPair();
-  Handle<FixedArray> details =
-      isolate->factory()->NewFixedArray(has_js_accessors ? 6 : 3);
-  details->set(0, *value);
-  // TODO(verwaest): Get rid of this random way of handling interceptors.
-  PropertyDetails d = it.state() == LookupIterator::INTERCEPTOR
-                          ? PropertyDetails::Empty()
-                          : it.property_details();
-  details->set(1, d.AsSmi());
-  details->set(
-      2, isolate->heap()->ToBoolean(it.state() == LookupIterator::INTERCEPTOR));
-  if (has_js_accessors) {
-    Handle<AccessorPair> accessors = Handle<AccessorPair>::cast(maybe_pair);
-    details->set(3, isolate->heap()->ToBoolean(has_caught));
-    Handle<Object> getter =
-        AccessorPair::GetComponent(accessors, ACCESSOR_GETTER);
-    Handle<Object> setter =
-        AccessorPair::GetComponent(accessors, ACCESSOR_SETTER);
-    details->set(4, *getter);
-    details->set(5, *setter);
-  }
-
-  return *isolate->factory()->NewJSArrayWithElements(details);
-}
-
-
-RUNTIME_FUNCTION(Runtime_DebugGetProperty) {
-  HandleScope scope(isolate);
-
-  DCHECK_EQ(2, args.length());
-
-  CONVERT_ARG_HANDLE_CHECKED(Object, obj, 0);
-  CONVERT_ARG_HANDLE_CHECKED(Name, name, 1);
-
-  LookupIterator it(obj, name);
-  return *DebugGetProperty(&it);
-}
-
-// Return the property kind calculated from the property details.
-// args[0]: smi with property details.
-RUNTIME_FUNCTION(Runtime_DebugPropertyKindFromDetails) {
-  SealHandleScope shs(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_PROPERTY_DETAILS_CHECKED(details, 0);
-  return Smi::FromInt(static_cast<int>(details.kind()));
-}
-
-
-// Return the property attribute calculated from the property details.
-// args[0]: smi with property details.
-RUNTIME_FUNCTION(Runtime_DebugPropertyAttributesFromDetails) {
-  SealHandleScope shs(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_PROPERTY_DETAILS_CHECKED(details, 0);
-  return Smi::FromInt(static_cast<int>(details.attributes()));
-}
-
-
-RUNTIME_FUNCTION(Runtime_CheckExecutionState) {
-  SealHandleScope shs(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-  return isolate->heap()->true_value();
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetFrameCount) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  // Count all frames which are relevant to debugging stack trace.
-  int n = 0;
-  StackFrame::Id id = isolate->debug()->break_frame_id();
-  if (id == StackFrame::NO_ID) {
-    // If there is no JavaScript stack frame count is 0.
-    return Smi::kZero;
-  }
-
-  std::vector<FrameSummary> frames;
-  for (StackTraceFrameIterator it(isolate, id); !it.done(); it.Advance()) {
-    frames.clear();
-    it.frame()->Summarize(&frames);
-    for (size_t i = frames.size(); i != 0; i--) {
-      // Omit functions from native and extension scripts.
-      if (frames[i - 1].is_subject_to_debugging()) n++;
-    }
-  }
-  return Smi::FromInt(n);
-}
-
-static const int kFrameDetailsFrameIdIndex = 0;
-static const int kFrameDetailsReceiverIndex = 1;
-static const int kFrameDetailsFunctionIndex = 2;
-static const int kFrameDetailsScriptIndex = 3;
-static const int kFrameDetailsArgumentCountIndex = 4;
-static const int kFrameDetailsLocalCountIndex = 5;
-static const int kFrameDetailsSourcePositionIndex = 6;
-static const int kFrameDetailsConstructCallIndex = 7;
-static const int kFrameDetailsAtReturnIndex = 8;
-static const int kFrameDetailsFlagsIndex = 9;
-static const int kFrameDetailsFirstDynamicIndex = 10;
-
-// Return an array with frame details
-// args[0]: number: break id
-// args[1]: number: frame index
-//
-// The array returned contains the following information:
-// 0: Frame id
-// 1: Receiver
-// 2: Function
-// 3: Script
-// 4: Argument count
-// 5: Local count
-// 6: Source position
-// 7: Constructor call
-// 8: Is at return
-// 9: Flags
-// Arguments name, value
-// Locals name, value
-// Return value if any
-RUNTIME_FUNCTION(Runtime_GetFrameDetails) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_NUMBER_CHECKED(int, index, Int32, args[1]);
-  Heap* heap = isolate->heap();
-
-  // Find the relevant frame with the requested index.
-  StackFrame::Id id = isolate->debug()->break_frame_id();
-  if (id == StackFrame::NO_ID) {
-    // If there are no JavaScript stack frames return undefined.
-    return heap->undefined_value();
-  }
-
-  StackTraceFrameIterator it(isolate, id);
-  // Inlined frame index in optimized frame, starting from outer function.
-  int inlined_frame_index =
-      DebugFrameHelper::FindIndexedNonNativeFrame(&it, index);
-  if (inlined_frame_index == -1) return heap->undefined_value();
-
-  FrameInspector frame_inspector(it.frame(), inlined_frame_index, isolate);
-
-  // Traverse the saved contexts chain to find the active context for the
-  // selected frame.
-  SaveContext* save =
-      DebugFrameHelper::FindSavedContextForFrame(isolate, it.frame());
-
-  // Get the frame id.
-  Handle<Object> frame_id(DebugFrameHelper::WrapFrameId(it.frame()->id()),
-                          isolate);
-
-  if (frame_inspector.IsWasm()) {
-    // Create the details array (no dynamic information for wasm).
-    Handle<FixedArray> details =
-        isolate->factory()->NewFixedArray(kFrameDetailsFirstDynamicIndex);
-
-    // Add the frame id.
-    details->set(kFrameDetailsFrameIdIndex, *frame_id);
-
-    // Add the function name.
-    Handle<String> func_name = frame_inspector.GetFunctionName();
-    details->set(kFrameDetailsFunctionIndex, *func_name);
-
-    // Add the script wrapper
-    Handle<Object> script_wrapper =
-        Script::GetWrapper(frame_inspector.GetScript());
-    details->set(kFrameDetailsScriptIndex, *script_wrapper);
-
-    // Add the arguments count.
-    details->set(kFrameDetailsArgumentCountIndex, Smi::kZero);
-
-    // Add the locals count
-    details->set(kFrameDetailsLocalCountIndex, Smi::kZero);
-
-    // Add the source position.
-    int position = frame_inspector.GetSourcePosition();
-    details->set(kFrameDetailsSourcePositionIndex, Smi::FromInt(position));
-
-    // Add the constructor information.
-    details->set(kFrameDetailsConstructCallIndex, heap->ToBoolean(false));
-
-    // Add the at return information.
-    details->set(kFrameDetailsAtReturnIndex, heap->ToBoolean(false));
-
-    // Add flags to indicate information on whether this frame is
-    //   bit 0: invoked in the debugger context.
-    //   bit 1: optimized frame.
-    //   bit 2: inlined in optimized frame
-    int flags = inlined_frame_index << 2;
-    if (*save->context() == *isolate->debug()->debug_context()) {
-      flags |= 1 << 0;
-    }
-    details->set(kFrameDetailsFlagsIndex, Smi::FromInt(flags));
-
-    return *isolate->factory()->NewJSArrayWithElements(details);
-  }
-
-  // Find source position in unoptimized code.
-  int position = frame_inspector.GetSourcePosition();
-
-  // Handle JavaScript frames.
-  bool is_optimized = it.frame()->is_optimized();
-
-  // Check for constructor frame.
-  bool constructor = frame_inspector.IsConstructor();
-
-  // Get scope info and read from it for local variable information.
-  Handle<JSFunction> function =
-      Handle<JSFunction>::cast(frame_inspector.GetFunction());
-  CHECK(function->shared()->IsSubjectToDebugging());
-  Handle<SharedFunctionInfo> shared(function->shared());
-  Handle<ScopeInfo> scope_info(shared->scope_info());
-  DCHECK(*scope_info != ScopeInfo::Empty(isolate));
-
-  // Get the locals names and values into a temporary array.
-  Handle<Object> maybe_context = frame_inspector.GetContext();
-  const int local_count_with_synthetic = maybe_context->IsContext()
-                                             ? scope_info->LocalCount()
-                                             : scope_info->StackLocalCount();
-  int local_count = local_count_with_synthetic;
-  for (int slot = 0; slot < local_count_with_synthetic; ++slot) {
-    // Hide compiler-introduced temporary variables, whether on the stack or on
-    // the context.
-    if (ScopeInfo::VariableIsSynthetic(scope_info->LocalName(slot))) {
-      local_count--;
-    }
-  }
-
-  std::vector<Handle<Object>> locals;
-  // Fill in the values of the locals.
-  int i = 0;
-  for (; i < scope_info->StackLocalCount(); ++i) {
-    // Use the value from the stack.
-    if (ScopeInfo::VariableIsSynthetic(scope_info->LocalName(i))) continue;
-    locals.emplace_back(scope_info->LocalName(i), isolate);
-    Handle<Object> value =
-        frame_inspector.GetExpression(scope_info->StackLocalIndex(i));
-    // TODO(yangguo): We convert optimized out values to {undefined} when they
-    // are passed to the debugger. Eventually we should handle them somehow.
-    if (value->IsOptimizedOut(isolate)) {
-      value = isolate->factory()->undefined_value();
-    }
-    locals.push_back(value);
-  }
-  if (static_cast<int>(locals.size()) < local_count * 2) {
-    // Get the context containing declarations.
-    DCHECK(maybe_context->IsContext());
-    Handle<Context> context(Context::cast(*maybe_context)->closure_context());
-
-    for (; i < scope_info->LocalCount(); ++i) {
-      Handle<String> name(scope_info->LocalName(i));
-      if (ScopeInfo::VariableIsSynthetic(*name)) continue;
-      VariableMode mode;
-      InitializationFlag init_flag;
-      MaybeAssignedFlag maybe_assigned_flag;
-      locals.push_back(name);
-      int context_slot_index = ScopeInfo::ContextSlotIndex(
-          scope_info, name, &mode, &init_flag, &maybe_assigned_flag);
-      Object* value = context->get(context_slot_index);
-      locals.emplace_back(value, isolate);
-    }
-  }
-
-  // Check whether this frame is positioned at return. If not top
-  // frame or if the frame is optimized it cannot be at a return.
-  bool at_return = false;
-  if (!is_optimized && index == 0) {
-    at_return = isolate->debug()->IsBreakAtReturn(it.javascript_frame());
-  }
-
-  // If positioned just before return find the value to be returned and add it
-  // to the frame information.
-  Handle<Object> return_value = isolate->factory()->undefined_value();
-  if (at_return) {
-    return_value = handle(isolate->debug()->return_value(), isolate);
-  }
-
-  // Now advance to the arguments adapter frame (if any). It contains all
-  // the provided parameters whereas the function frame always have the number
-  // of arguments matching the functions parameters. The rest of the
-  // information (except for what is collected above) is the same.
-  if ((inlined_frame_index == 0) &&
-      it.javascript_frame()->has_adapted_arguments()) {
-    it.AdvanceOneFrame();
-    DCHECK(it.frame()->is_arguments_adaptor());
-    frame_inspector.SetArgumentsFrame(it.frame());
-  }
-
-  // Find the number of arguments to fill. At least fill the number of
-  // parameters for the function and fill more if more parameters are provided.
-  int argument_count = scope_info->ParameterCount();
-  if (argument_count < frame_inspector.GetParametersCount()) {
-    argument_count = frame_inspector.GetParametersCount();
-  }
-
-  // Calculate the size of the result.
-  int details_size = kFrameDetailsFirstDynamicIndex +
-                     2 * (argument_count + local_count) + (at_return ? 1 : 0);
-  Handle<FixedArray> details = isolate->factory()->NewFixedArray(details_size);
-
-  // Add the frame id.
-  details->set(kFrameDetailsFrameIdIndex, *frame_id);
-
-  // Add the function (same as in function frame).
-  details->set(kFrameDetailsFunctionIndex, *(frame_inspector.GetFunction()));
-
-  // Add the script wrapper
-  Handle<Object> script_wrapper =
-      Script::GetWrapper(frame_inspector.GetScript());
-  details->set(kFrameDetailsScriptIndex, *script_wrapper);
-
-  // Add the arguments count.
-  details->set(kFrameDetailsArgumentCountIndex, Smi::FromInt(argument_count));
-
-  // Add the locals count
-  details->set(kFrameDetailsLocalCountIndex, Smi::FromInt(local_count));
-
-  // Add the source position.
-  if (position != kNoSourcePosition) {
-    details->set(kFrameDetailsSourcePositionIndex, Smi::FromInt(position));
-  } else {
-    details->set(kFrameDetailsSourcePositionIndex, heap->undefined_value());
-  }
-
-  // Add the constructor information.
-  details->set(kFrameDetailsConstructCallIndex, heap->ToBoolean(constructor));
-
-  // Add the at return information.
-  details->set(kFrameDetailsAtReturnIndex, heap->ToBoolean(at_return));
-
-  // Add flags to indicate information on whether this frame is
-  //   bit 0: invoked in the debugger context.
-  //   bit 1: optimized frame.
-  //   bit 2: inlined in optimized frame
-  int flags = 0;
-  if (*save->context() == *isolate->debug()->debug_context()) {
-    flags |= 1 << 0;
-  }
-  if (is_optimized) {
-    flags |= 1 << 1;
-    flags |= inlined_frame_index << 2;
-  }
-  details->set(kFrameDetailsFlagsIndex, Smi::FromInt(flags));
-
-  // Fill the dynamic part.
-  int details_index = kFrameDetailsFirstDynamicIndex;
-
-  // Add arguments name and value.
-  for (int i = 0; i < argument_count; i++) {
-    // Name of the argument.
-    if (i < scope_info->ParameterCount()) {
-      details->set(details_index++, scope_info->ParameterName(i));
-    } else {
-      details->set(details_index++, heap->undefined_value());
-    }
-
-    // Parameter value.
-    if (i < frame_inspector.GetParametersCount()) {
-      // Get the value from the stack.
-      details->set(details_index++, *(frame_inspector.GetParameter(i)));
-    } else {
-      details->set(details_index++, heap->undefined_value());
-    }
-  }
-
-  // Add locals name and value from the temporary copy from the function frame.
-  for (const auto& local : locals) details->set(details_index++, *local);
-
-  // Add the value being returned.
-  if (at_return) {
-    details->set(details_index++, *return_value);
-  }
-
-  // Add the receiver (same as in function frame).
-  Handle<Object> receiver = frame_inspector.GetReceiver();
-  DCHECK(function->shared()->IsUserJavaScript());
-  // Optimized frames only restore the receiver as best-effort (see
-  // OptimizedFrame::Summarize).
-  DCHECK_IMPLIES(!is_optimized && is_sloppy(shared->language_mode()),
-                 receiver->IsJSReceiver());
-  details->set(kFrameDetailsReceiverIndex, *receiver);
-
-  DCHECK_EQ(details_size, details_index);
-  return *isolate->factory()->NewJSArrayWithElements(details);
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetScopeCount) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_SMI_ARG_CHECKED(wrapped_id, 1);
-
-  // Get the frame where the debugging is performed.
-  StackFrame::Id id = DebugFrameHelper::UnwrapFrameId(wrapped_id);
-  StackTraceFrameIterator it(isolate, id);
-  StandardFrame* frame = it.frame();
-  if (it.frame()->is_wasm()) return 0;
-
-  FrameInspector frame_inspector(frame, 0, isolate);
-
-  // Count the visible scopes.
-  int n = 0;
-  for (ScopeIterator it(isolate, &frame_inspector); !it.Done(); it.Next()) {
-    n++;
-  }
-
-  return Smi::FromInt(n);
-}
-
-
-// Return an array with scope details
-// args[0]: number: break id
-// args[1]: number: frame index
-// args[2]: number: inlined frame index
-// args[3]: number: scope index
-//
-// The array returned contains the following information:
-// 0: Scope type
-// 1: Scope object
-RUNTIME_FUNCTION(Runtime_GetScopeDetails) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(4, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_SMI_ARG_CHECKED(wrapped_id, 1);
-  CONVERT_NUMBER_CHECKED(int, inlined_jsframe_index, Int32, args[2]);
-  CONVERT_NUMBER_CHECKED(int, index, Int32, args[3]);
-
-  // Get the frame where the debugging is performed.
-  StackFrame::Id id = DebugFrameHelper::UnwrapFrameId(wrapped_id);
-  StackTraceFrameIterator frame_it(isolate, id);
-  // Wasm has no scopes, this must be javascript.
-  JavaScriptFrame* frame = JavaScriptFrame::cast(frame_it.frame());
-  FrameInspector frame_inspector(frame, inlined_jsframe_index, isolate);
-
-  // Find the requested scope.
-  int n = 0;
-  ScopeIterator it(isolate, &frame_inspector);
-  for (; !it.Done() && n < index; it.Next()) {
-    n++;
-  }
-  if (it.Done()) {
-    return isolate->heap()->undefined_value();
-  }
-  RETURN_RESULT_OR_FAILURE(isolate, it.MaterializeScopeDetails());
-}
-
-
-// Return an array of scope details
-// args[0]: number: break id
-// args[1]: number: frame index
-// args[2]: number: inlined frame index
-// args[3]: boolean: ignore nested scopes
-//
-// The array returned contains arrays with the following information:
-// 0: Scope type
-// 1: Scope object
-RUNTIME_FUNCTION(Runtime_GetAllScopesDetails) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 3 || args.length() == 4);
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_SMI_ARG_CHECKED(wrapped_id, 1);
-  CONVERT_NUMBER_CHECKED(int, inlined_frame_index, Int32, args[2]);
-
-  ScopeIterator::Option option = ScopeIterator::DEFAULT;
-  if (args.length() == 4) {
-    CONVERT_BOOLEAN_ARG_CHECKED(flag, 3);
-    if (flag) option = ScopeIterator::IGNORE_NESTED_SCOPES;
-  }
-
-  // Get the frame where the debugging is performed.
-  StackFrame::Id id = DebugFrameHelper::UnwrapFrameId(wrapped_id);
-  StackTraceFrameIterator frame_it(isolate, id);
-  StandardFrame* frame = frame_it.frame();
-
-  // Handle wasm frames specially. They provide exactly two scopes (global /
-  // local).
-  if (frame->is_wasm_interpreter_entry()) {
-    Handle<WasmDebugInfo> debug_info(
-        WasmInterpreterEntryFrame::cast(frame)->debug_info(), isolate);
-    return *WasmDebugInfo::GetScopeDetails(debug_info, frame->fp(),
-                                           inlined_frame_index);
-  }
-
-  FrameInspector frame_inspector(frame, inlined_frame_index, isolate);
-  std::vector<Handle<JSObject>> result;
-  ScopeIterator it(isolate, &frame_inspector, option);
-  for (; !it.Done(); it.Next()) {
-    Handle<JSObject> details;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, details,
-                                       it.MaterializeScopeDetails());
-    result.push_back(details);
-  }
-
-  int result_size = static_cast<int>(result.size());
-  Handle<FixedArray> array = isolate->factory()->NewFixedArray(result_size);
-  for (int i = 0; i < result_size; ++i) {
-    array->set(i, *result[i]);
-  }
-  return *isolate->factory()->NewJSArrayWithElements(array);
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetFunctionScopeCount) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-
-  // Check arguments.
-  CONVERT_ARG_HANDLE_CHECKED(JSReceiver, function, 0);
-
-  // Count the visible scopes.
-  int n = 0;
-  if (function->IsJSFunction()) {
-    for (ScopeIterator it(isolate, Handle<JSFunction>::cast(function));
-         !it.Done(); it.Next()) {
-      n++;
-    }
-  }
-
-  return Smi::FromInt(n);
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetFunctionScopeDetails) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-
-  // Check arguments.
-  CONVERT_ARG_HANDLE_CHECKED(JSFunction, fun, 0);
-  CONVERT_NUMBER_CHECKED(int, index, Int32, args[1]);
-
-  // Find the requested scope.
-  int n = 0;
-  ScopeIterator it(isolate, fun);
-  for (; !it.Done() && n < index; it.Next()) {
-    n++;
-  }
-  if (it.Done()) {
-    return isolate->heap()->undefined_value();
-  }
-
-  RETURN_RESULT_OR_FAILURE(isolate, it.MaterializeScopeDetails());
-}
-
 RUNTIME_FUNCTION(Runtime_GetGeneratorScopeCount) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
@@ -977,7 +314,7 @@ RUNTIME_FUNCTION(Runtime_GetGeneratorScopeDetails) {
   DCHECK_EQ(2, args.length());
 
   if (!args[0]->IsJSGeneratorObject()) {
-    return isolate->heap()->undefined_value();
+    return ReadOnlyRoots(isolate).undefined_value();
   }
 
   // Check arguments.
@@ -986,7 +323,7 @@ RUNTIME_FUNCTION(Runtime_GetGeneratorScopeDetails) {
 
   // Only inspect suspended generator scopes.
   if (!gen->is_suspended()) {
-    return isolate->heap()->undefined_value();
+    return ReadOnlyRoots(isolate).undefined_value();
   }
 
   // Find the requested scope.
@@ -996,10 +333,10 @@ RUNTIME_FUNCTION(Runtime_GetGeneratorScopeDetails) {
     n++;
   }
   if (it.Done()) {
-    return isolate->heap()->undefined_value();
+    return ReadOnlyRoots(isolate).undefined_value();
   }
 
-  RETURN_RESULT_OR_FAILURE(isolate, it.MaterializeScopeDetails());
+  return *it.MaterializeScopeDetails();
 }
 
 static bool SetScopeVariableValue(ScopeIterator* it, int index,
@@ -1014,52 +351,22 @@ static bool SetScopeVariableValue(ScopeIterator* it, int index,
   return it->SetVariableValue(variable_name, new_value);
 }
 
-
 // Change variable value in closure or local scope
 // args[0]: number or JsFunction: break id or function
-// args[1]: number: frame index (when arg[0] is break id)
-// args[2]: number: inlined frame index (when arg[0] is break id)
-// args[3]: number: scope index
-// args[4]: string: variable name
-// args[5]: object: new value
+// args[1]: number: scope index
+// args[2]: string: variable name
+// args[3]: object: new value
 //
 // Return true if success and false otherwise
-RUNTIME_FUNCTION(Runtime_SetScopeVariableValue) {
+RUNTIME_FUNCTION(Runtime_SetGeneratorScopeVariableValue) {
   HandleScope scope(isolate);
-  DCHECK_EQ(6, args.length());
-
-  // Check arguments.
-  CONVERT_NUMBER_CHECKED(int, index, Int32, args[3]);
-  CONVERT_ARG_HANDLE_CHECKED(String, variable_name, 4);
-  CONVERT_ARG_HANDLE_CHECKED(Object, new_value, 5);
-
-  bool res;
-  if (args[0]->IsNumber()) {
-    CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-    CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-    CONVERT_SMI_ARG_CHECKED(wrapped_id, 1);
-    CONVERT_NUMBER_CHECKED(int, inlined_jsframe_index, Int32, args[2]);
-
-    // Get the frame where the debugging is performed.
-    StackFrame::Id id = DebugFrameHelper::UnwrapFrameId(wrapped_id);
-    StackTraceFrameIterator frame_it(isolate, id);
-    // Wasm has no scopes, this must be javascript.
-    JavaScriptFrame* frame = JavaScriptFrame::cast(frame_it.frame());
-    FrameInspector frame_inspector(frame, inlined_jsframe_index, isolate);
-
-    ScopeIterator it(isolate, &frame_inspector);
-    res = SetScopeVariableValue(&it, index, variable_name, new_value);
-  } else if (args[0]->IsJSFunction()) {
-    CONVERT_ARG_HANDLE_CHECKED(JSFunction, fun, 0);
-    ScopeIterator it(isolate, fun);
-    res = SetScopeVariableValue(&it, index, variable_name, new_value);
-  } else {
-    CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, gen, 0);
-    ScopeIterator it(isolate, gen);
-    res = SetScopeVariableValue(&it, index, variable_name, new_value);
-  }
-
+  DCHECK_EQ(4, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, gen, 0);
+  CONVERT_NUMBER_CHECKED(int, index, Int32, args[1]);
+  CONVERT_ARG_HANDLE_CHECKED(String, variable_name, 2);
+  CONVERT_ARG_HANDLE_CHECKED(Object, new_value, 3);
+  ScopeIterator it(isolate, gen);
+  bool res = SetScopeVariableValue(&it, index, variable_name, new_value);
   return isolate->heap()->ToBoolean(res);
 }
 
@@ -1070,11 +377,12 @@ RUNTIME_FUNCTION(Runtime_GetBreakLocations) {
   CHECK(isolate->debug()->is_active());
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, fun, 0);
 
-  Handle<SharedFunctionInfo> shared(fun->shared());
+  Handle<SharedFunctionInfo> shared(fun->shared(), isolate);
   // Find the number of break points
-  Handle<Object> break_locations = Debug::GetSourceBreakLocations(shared);
+  Handle<Object> break_locations =
+      Debug::GetSourceBreakLocations(isolate, shared);
   if (break_locations->IsUndefined(isolate)) {
-    return isolate->heap()->undefined_value();
+    return ReadOnlyRoots(isolate).undefined_value();
   }
   // Return array as JS array
   return *isolate->factory()->NewJSArrayWithElements(
@@ -1082,24 +390,6 @@ RUNTIME_FUNCTION(Runtime_GetBreakLocations) {
 }
 
 
-// Change the state of break on exceptions.
-// args[0]: Enum value indicating whether to affect caught/uncaught exceptions.
-// args[1]: Boolean indicating on/off.
-RUNTIME_FUNCTION(Runtime_ChangeBreakOnException) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_NUMBER_CHECKED(uint32_t, type_arg, Uint32, args[0]);
-  CONVERT_BOOLEAN_ARG_CHECKED(enable, 1);
-
-  // If the number doesn't match an enum value, the ChangeBreakOnException
-  // function will default to affecting caught exceptions.
-  ExceptionBreakType type = static_cast<ExceptionBreakType>(type_arg);
-  // Update break point state.
-  isolate->debug()->ChangeBreakOnException(type, enable);
-  return isolate->heap()->undefined_value();
-}
-
-
 // Returns the state of break on exceptions
 // args[0]: boolean indicating uncaught exceptions
 RUNTIME_FUNCTION(Runtime_IsBreakOnException) {
@@ -1112,256 +402,36 @@ RUNTIME_FUNCTION(Runtime_IsBreakOnException) {
   return Smi::FromInt(result);
 }
 
-
-// Prepare for stepping
-// args[0]: break id for checking execution state
-// args[1]: step action from the enumeration StepAction
-// args[2]: number of times to perform the step, for step out it is the number
-//          of frames to step down.
-RUNTIME_FUNCTION(Runtime_PrepareStep) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  if (!args[1]->IsNumber()) {
-    return isolate->Throw(isolate->heap()->illegal_argument_string());
-  }
-
-  // Get the step action and check validity.
-  StepAction step_action = static_cast<StepAction>(NumberToInt32(args[1]));
-  if (step_action != StepIn && step_action != StepNext &&
-      step_action != StepOut) {
-    return isolate->Throw(isolate->heap()->illegal_argument_string());
-  }
-
-  // Clear all current stepping setup.
-  isolate->debug()->ClearStepping();
-
-  // Prepare step.
-  isolate->debug()->PrepareStep(static_cast<StepAction>(step_action));
-  return isolate->heap()->undefined_value();
-}
-
 // Clear all stepping set by PrepareStep.
 RUNTIME_FUNCTION(Runtime_ClearStepping) {
   HandleScope scope(isolate);
   DCHECK_EQ(0, args.length());
   CHECK(isolate->debug()->is_active());
   isolate->debug()->ClearStepping();
-  return isolate->heap()->undefined_value();
-}
-
-
-RUNTIME_FUNCTION(Runtime_DebugEvaluate) {
-  HandleScope scope(isolate);
-
-  // Check the execution state and decode arguments frame and source to be
-  // evaluated.
-  DCHECK_EQ(5, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_SMI_ARG_CHECKED(wrapped_id, 1);
-  CONVERT_NUMBER_CHECKED(int, inlined_jsframe_index, Int32, args[2]);
-  CONVERT_ARG_HANDLE_CHECKED(String, source, 3);
-  CONVERT_BOOLEAN_ARG_CHECKED(throw_on_side_effect, 4);
-
-  StackFrame::Id id = DebugFrameHelper::UnwrapFrameId(wrapped_id);
-
-  RETURN_RESULT_OR_FAILURE(
-      isolate, DebugEvaluate::Local(isolate, id, inlined_jsframe_index, source,
-                                    throw_on_side_effect));
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
-
-RUNTIME_FUNCTION(Runtime_DebugEvaluateGlobal) {
-  HandleScope scope(isolate);
-
-  // Check the execution state and decode arguments frame and source to be
-  // evaluated.
-  DCHECK_EQ(2, args.length());
-  CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
-  CHECK(isolate->debug()->CheckExecutionState(break_id));
-
-  CONVERT_ARG_HANDLE_CHECKED(String, source, 1);
-
-  RETURN_RESULT_OR_FAILURE(isolate,
-                           DebugEvaluate::Global(isolate, source, false));
-}
-
-
-RUNTIME_FUNCTION(Runtime_DebugGetLoadedScripts) {
+RUNTIME_FUNCTION(Runtime_DebugGetLoadedScriptIds) {
   HandleScope scope(isolate);
   DCHECK_EQ(0, args.length());
 
   Handle<FixedArray> instances;
   {
     DebugScope debug_scope(isolate->debug());
-    if (debug_scope.failed()) {
-      DCHECK(isolate->has_pending_exception());
-      return isolate->heap()->exception();
-    }
     // Fill the script objects.
     instances = isolate->debug()->GetLoadedScripts();
   }
 
   // Convert the script objects to proper JS objects.
   for (int i = 0; i < instances->length(); i++) {
-    Handle<Script> script = Handle<Script>(Script::cast(instances->get(i)));
-    // Get the script wrapper in a local handle before calling GetScriptWrapper,
-    // because using
-    //   instances->set(i, *GetScriptWrapper(script))
-    // is unsafe as GetScriptWrapper might call GC and the C++ compiler might
-    // already have dereferenced the instances handle.
-    Handle<JSObject> wrapper = Script::GetWrapper(script);
-    instances->set(i, *wrapper);
+    Handle<Script> script(Script::cast(instances->get(i)), isolate);
+    instances->set(i, Smi::FromInt(script->id()));
   }
 
   // Return result as a JS array.
   return *isolate->factory()->NewJSArrayWithElements(instances);
 }
 
-static bool HasInPrototypeChainIgnoringProxies(Isolate* isolate,
-                                               JSObject* object,
-                                               Object* proto) {
-  PrototypeIterator iter(isolate, object, kStartAtReceiver);
-  while (true) {
-    iter.AdvanceIgnoringProxies();
-    if (iter.IsAtEnd()) return false;
-    if (iter.GetCurrent() == proto) return true;
-  }
-}
-
-
-// Scan the heap for objects with direct references to an object
-// args[0]: the object to find references to
-// args[1]: constructor function for instances to exclude (Mirror)
-// args[2]: the the maximum number of objects to return
-RUNTIME_FUNCTION(Runtime_DebugReferencedBy) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSObject, target, 0);
-  CONVERT_ARG_HANDLE_CHECKED(Object, filter, 1);
-  CHECK(filter->IsUndefined(isolate) || filter->IsJSObject());
-  CONVERT_NUMBER_CHECKED(int32_t, max_references, Int32, args[2]);
-  CHECK_GE(max_references, 0);
-
-  std::vector<Handle<JSObject>> instances;
-  Heap* heap = isolate->heap();
-  {
-    HeapIterator iterator(heap, HeapIterator::kFilterUnreachable);
-    // Get the constructor function for context extension and arguments array.
-    Object* arguments_fun = isolate->sloppy_arguments_map()->GetConstructor();
-    HeapObject* heap_obj;
-    while ((heap_obj = iterator.next()) != nullptr) {
-      if (!heap_obj->IsJSObject()) continue;
-      JSObject* obj = JSObject::cast(heap_obj);
-      if (obj->IsJSContextExtensionObject()) continue;
-      if (obj->map()->GetConstructor() == arguments_fun) continue;
-      if (!obj->ReferencesObject(*target)) continue;
-      // Check filter if supplied. This is normally used to avoid
-      // references from mirror objects.
-      if (!filter->IsUndefined(isolate) &&
-          HasInPrototypeChainIgnoringProxies(isolate, obj, *filter)) {
-        continue;
-      }
-      if (obj->IsJSGlobalObject()) {
-        obj = JSGlobalObject::cast(obj)->global_proxy();
-      }
-      instances.emplace_back(obj);
-      if (static_cast<int32_t>(instances.size()) == max_references) break;
-    }
-    // Iterate the rest of the heap to satisfy HeapIterator constraints.
-    while (iterator.next()) {
-    }
-  }
-
-  Handle<FixedArray> result;
-  if (instances.size() == 1 && instances.back().is_identical_to(target)) {
-    // Check for circular reference only. This can happen when the object is
-    // only referenced from mirrors and has a circular reference in which case
-    // the object is not really alive and would have been garbage collected if
-    // not referenced from the mirror.
-    result = isolate->factory()->empty_fixed_array();
-  } else {
-    int instances_size = static_cast<int>(instances.size());
-    result = isolate->factory()->NewFixedArray(instances_size);
-    for (int i = 0; i < instances_size; ++i) result->set(i, *instances[i]);
-  }
-  return *isolate->factory()->NewJSArrayWithElements(result);
-}
-
-
-// Scan the heap for objects constructed by a specific function.
-// args[0]: the constructor to find instances of
-// args[1]: the the maximum number of objects to return
-RUNTIME_FUNCTION(Runtime_DebugConstructedBy) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSFunction, constructor, 0);
-  CONVERT_NUMBER_CHECKED(int32_t, max_references, Int32, args[1]);
-  CHECK_GE(max_references, 0);
-
-  std::vector<Handle<JSObject>> instances;
-  Heap* heap = isolate->heap();
-  {
-    HeapIterator iterator(heap, HeapIterator::kFilterUnreachable);
-    HeapObject* heap_obj;
-    while ((heap_obj = iterator.next()) != nullptr) {
-      if (!heap_obj->IsJSObject()) continue;
-      JSObject* obj = JSObject::cast(heap_obj);
-      if (obj->map()->GetConstructor() != *constructor) continue;
-      instances.emplace_back(obj);
-      if (static_cast<int32_t>(instances.size()) == max_references) break;
-    }
-    // Iterate the rest of the heap to satisfy HeapIterator constraints.
-    while (iterator.next()) {
-    }
-  }
-
-  int instances_size = static_cast<int>(instances.size());
-  Handle<FixedArray> result = isolate->factory()->NewFixedArray(instances_size);
-  for (int i = 0; i < instances_size; ++i) result->set(i, *instances[i]);
-  return *isolate->factory()->NewJSArrayWithElements(result);
-}
-
-
-// Find the effective prototype object as returned by __proto__.
-// args[0]: the object to find the prototype for.
-RUNTIME_FUNCTION(Runtime_DebugGetPrototype) {
-  HandleScope shs(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
-  // TODO(1543): Come up with a solution for clients to handle potential errors
-  // thrown by an intermediate proxy.
-  RETURN_RESULT_OR_FAILURE(isolate, JSReceiver::GetPrototype(isolate, obj));
-}
-
-
-// Patches script source (should be called upon BeforeCompile event).
-// TODO(5530): Remove once uses in debug.js are gone.
-RUNTIME_FUNCTION(Runtime_DebugSetScriptSource) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(2, args.length());
-
-  CONVERT_ARG_HANDLE_CHECKED(JSValue, script_wrapper, 0);
-  CONVERT_ARG_HANDLE_CHECKED(String, source, 1);
-
-  CHECK(script_wrapper->value()->IsScript());
-  Handle<Script> script(Script::cast(script_wrapper->value()));
-
-  // The following condition is not guaranteed to hold and a failure is also
-  // propagated to callers. Hence we fail gracefully here and don't crash.
-  if (script->compilation_state() != Script::COMPILATION_STATE_INITIAL) {
-    return isolate->ThrowIllegalOperation();
-  }
-
-  script->set_source(*source);
-
-  return isolate->heap()->undefined_value();
-}
-
 
 RUNTIME_FUNCTION(Runtime_FunctionGetInferredName) {
   SealHandleScope shs(isolate);
@@ -1371,41 +441,7 @@ RUNTIME_FUNCTION(Runtime_FunctionGetInferredName) {
   if (f->IsJSFunction()) {
     return JSFunction::cast(f)->shared()->inferred_name();
   }
-  return isolate->heap()->empty_string();
-}
-
-
-RUNTIME_FUNCTION(Runtime_FunctionGetDebugName) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-
-  CONVERT_ARG_HANDLE_CHECKED(JSReceiver, function, 0);
-
-  if (function->IsJSBoundFunction()) {
-    RETURN_RESULT_OR_FAILURE(
-        isolate, JSBoundFunction::GetName(
-                     isolate, Handle<JSBoundFunction>::cast(function)));
-  } else {
-    return *JSFunction::GetDebugName(Handle<JSFunction>::cast(function));
-  }
-}
-
-
-RUNTIME_FUNCTION(Runtime_GetDebugContext) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(0, args.length());
-  Handle<Context> context;
-  {
-    DebugScope debug_scope(isolate->debug());
-    if (debug_scope.failed()) {
-      DCHECK(isolate->has_pending_exception());
-      return isolate->heap()->exception();
-    }
-    context = isolate->debug()->GetDebugContext();
-  }
-  if (context.is_null()) return isolate->heap()->undefined_value();
-  context->set_security_token(isolate->native_context()->security_token());
-  return context->global_proxy();
+  return ReadOnlyRoots(isolate).empty_string();
 }
 
 
@@ -1416,7 +452,7 @@ RUNTIME_FUNCTION(Runtime_CollectGarbage) {
   DCHECK_EQ(1, args.length());
   isolate->heap()->CollectAllGarbage(Heap::kAbortIncrementalMarkingMask,
                                      GarbageCollectionReason::kRuntime);
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 
@@ -1431,56 +467,6 @@ RUNTIME_FUNCTION(Runtime_GetHeapUsage) {
   return Smi::FromInt(usage);
 }
 
-
-// Finds the script object from the script data. NOTE: This operation uses
-// heap traversal to find the function generated for the source position
-// for the requested break point. For lazily compiled functions several heap
-// traversals might be required rendering this operation as a rather slow
-// operation. However for setting break points which is normally done through
-// some kind of user interaction the performance is not crucial.
-RUNTIME_FUNCTION(Runtime_GetScript) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(String, script_name, 0);
-
-  Handle<Script> found;
-  {
-    Script::Iterator iterator(isolate);
-    Script* script = nullptr;
-    while ((script = iterator.Next()) != nullptr) {
-      if (!script->name()->IsString()) continue;
-      String* name = String::cast(script->name());
-      if (name->Equals(*script_name)) {
-        found = Handle<Script>(script, isolate);
-        break;
-      }
-    }
-  }
-
-  if (found.is_null()) return isolate->heap()->undefined_value();
-  return *Script::GetWrapper(found);
-}
-
-// TODO(5530): Remove once uses in debug.js are gone.
-RUNTIME_FUNCTION(Runtime_ScriptLineCount) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_ARG_CHECKED(JSValue, script, 0);
-
-  CHECK(script->value()->IsScript());
-  Handle<Script> script_handle = Handle<Script>(Script::cast(script->value()));
-
-  if (script_handle->type() == Script::TYPE_WASM) {
-    // Return 0 for now; this function will disappear soon anyway.
-    return Smi::FromInt(0);
-  }
-
-  Script::InitLineEnds(script_handle);
-
-  FixedArray* line_ends_array = FixedArray::cast(script_handle->line_ends());
-  return Smi::FromInt(line_ends_array->length());
-}
-
 namespace {
 
 int ScriptLinePosition(Handle<Script> script, int line) {
@@ -1488,7 +474,6 @@ int ScriptLinePosition(Handle<Script> script, int line) {
 
   if (script->type() == Script::TYPE_WASM) {
     return WasmModuleObject::cast(script->wasm_module_object())
-        ->shared()
         ->GetFunctionOffset(line);
   }
 
@@ -1504,11 +489,24 @@ int ScriptLinePosition(Handle<Script> script, int line) {
   return Smi::ToInt(line_ends_array->get(line - 1)) + 1;
 }
 
-}  // namespace
+int ScriptLinePositionWithOffset(Handle<Script> script, int line, int offset) {
+  if (line < 0 || offset < 0) return -1;
+
+  if (line == 0 || offset == 0)
+    return ScriptLinePosition(script, line) + offset;
+
+  Script::PositionInfo info;
+  if (!Script::GetPositionInfo(script, offset, &info, Script::NO_OFFSET)) {
+    return -1;
+  }
 
-static Handle<Object> GetJSPositionInfo(Handle<Script> script, int position,
-                                        Script::OffsetFlag offset_flag,
-                                        Isolate* isolate) {
+  const int total_line = info.line + line;
+  return ScriptLinePosition(script, total_line);
+}
+
+Handle<Object> GetJSPositionInfo(Handle<Script> script, int position,
+                                 Script::OffsetFlag offset_flag,
+                                 Isolate* isolate) {
   Script::PositionInfo info;
   if (!Script::GetPositionInfo(script, position, &info, offset_flag)) {
     return isolate->factory()->null_value();
@@ -1523,37 +521,21 @@ static Handle<Object> GetJSPositionInfo(Handle<Script> script, int position,
   Handle<JSObject> jsinfo =
       isolate->factory()->NewJSObject(isolate->object_function());
 
-  JSObject::AddProperty(jsinfo, isolate->factory()->script_string(), script,
-                        NONE);
-  JSObject::AddProperty(jsinfo, isolate->factory()->position_string(),
+  JSObject::AddProperty(isolate, jsinfo, isolate->factory()->script_string(),
+                        script, NONE);
+  JSObject::AddProperty(isolate, jsinfo, isolate->factory()->position_string(),
                         handle(Smi::FromInt(position), isolate), NONE);
-  JSObject::AddProperty(jsinfo, isolate->factory()->line_string(),
+  JSObject::AddProperty(isolate, jsinfo, isolate->factory()->line_string(),
                         handle(Smi::FromInt(info.line), isolate), NONE);
-  JSObject::AddProperty(jsinfo, isolate->factory()->column_string(),
+  JSObject::AddProperty(isolate, jsinfo, isolate->factory()->column_string(),
                         handle(Smi::FromInt(info.column), isolate), NONE);
-  JSObject::AddProperty(jsinfo, isolate->factory()->sourceText_string(),
-                        sourceText, NONE);
+  JSObject::AddProperty(isolate, jsinfo,
+                        isolate->factory()->sourceText_string(), sourceText,
+                        NONE);
 
   return jsinfo;
 }
 
-namespace {
-
-int ScriptLinePositionWithOffset(Handle<Script> script, int line, int offset) {
-  if (line < 0 || offset < 0) return -1;
-
-  if (line == 0 || offset == 0)
-    return ScriptLinePosition(script, line) + offset;
-
-  Script::PositionInfo info;
-  if (!Script::GetPositionInfo(script, offset, &info, Script::NO_OFFSET)) {
-    return -1;
-  }
-
-  const int total_line = info.line + line;
-  return ScriptLinePosition(script, total_line);
-}
-
 Handle<Object> ScriptLocationFromLine(Isolate* isolate, Handle<Script> script,
                                       Handle<Object> opt_line,
                                       Handle<Object> opt_column,
@@ -1587,7 +569,7 @@ bool GetScriptById(Isolate* isolate, int needle, Handle<Script>* result) {
   Script* script = nullptr;
   while ((script = iterator.Next()) != nullptr) {
     if (script->id() == needle) {
-      *result = handle(script);
+      *result = handle(script, isolate);
       return true;
     }
   }
@@ -1597,30 +579,6 @@ bool GetScriptById(Isolate* isolate, int needle, Handle<Script>* result) {
 
 }  // namespace
 
-// Get information on a specific source line and column possibly offset by a
-// fixed source position. This function is used to find a source position from
-// a line and column position. The fixed source position offset is typically
-// used to find a source position in a function based on a line and column in
-// the source for the function alone. The offset passed will then be the
-// start position of the source for the function within the full script source.
-// Note that incoming line and column parameters may be undefined, and are
-// assumed to be passed *with* offsets.
-// TODO(5530): Remove once uses in debug.js are gone.
-RUNTIME_FUNCTION(Runtime_ScriptLocationFromLine) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(4, args.length());
-  CONVERT_ARG_HANDLE_CHECKED(JSValue, script, 0);
-  CONVERT_ARG_HANDLE_CHECKED(Object, opt_line, 1);
-  CONVERT_ARG_HANDLE_CHECKED(Object, opt_column, 2);
-  CONVERT_NUMBER_CHECKED(int32_t, offset, Int32, args[3]);
-
-  CHECK(script->value()->IsScript());
-  Handle<Script> script_handle = Handle<Script>(Script::cast(script->value()));
-
-  return *ScriptLocationFromLine(isolate, script_handle, opt_line, opt_column,
-                                 offset);
-}
-
 // TODO(5530): Rename once conflicting function has been deleted.
 RUNTIME_FUNCTION(Runtime_ScriptLocationFromLine2) {
   HandleScope scope(isolate);
@@ -1636,38 +594,6 @@ RUNTIME_FUNCTION(Runtime_ScriptLocationFromLine2) {
   return *ScriptLocationFromLine(isolate, script, opt_line, opt_column, offset);
 }
 
-// TODO(5530): Remove once uses in debug.js are gone.
-RUNTIME_FUNCTION(Runtime_ScriptPositionInfo) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  CONVERT_ARG_CHECKED(JSValue, script, 0);
-  CONVERT_NUMBER_CHECKED(int32_t, position, Int32, args[1]);
-  CONVERT_BOOLEAN_ARG_CHECKED(with_offset, 2);
-
-  CHECK(script->value()->IsScript());
-  Handle<Script> script_handle = Handle<Script>(Script::cast(script->value()));
-
-  const Script::OffsetFlag offset_flag =
-      with_offset ? Script::WITH_OFFSET : Script::NO_OFFSET;
-  return *GetJSPositionInfo(script_handle, position, offset_flag, isolate);
-}
-
-// TODO(5530): Rename once conflicting function has been deleted.
-RUNTIME_FUNCTION(Runtime_ScriptPositionInfo2) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(3, args.length());
-  CONVERT_NUMBER_CHECKED(int32_t, scriptid, Int32, args[0]);
-  CONVERT_NUMBER_CHECKED(int32_t, position, Int32, args[1]);
-  CONVERT_BOOLEAN_ARG_CHECKED(with_offset, 2);
-
-  Handle<Script> script;
-  CHECK(GetScriptById(isolate, scriptid, &script));
-
-  const Script::OffsetFlag offset_flag =
-      with_offset ? Script::WITH_OFFSET : Script::NO_OFFSET;
-  return *GetJSPositionInfo(script, position, offset_flag, isolate);
-}
-
 // On function call, depending on circumstances, prepare for stepping in,
 // or perform a side effect check.
 RUNTIME_FUNCTION(Runtime_DebugOnFunctionCall) {
@@ -1678,16 +604,17 @@ RUNTIME_FUNCTION(Runtime_DebugOnFunctionCall) {
   if (isolate->debug()->needs_check_on_function_call()) {
     // Ensure that the callee will perform debug check on function call too.
     Deoptimizer::DeoptimizeFunction(*fun);
-    if (isolate->debug()->last_step_action() >= StepIn) {
+    if (isolate->debug()->last_step_action() >= StepIn ||
+        isolate->debug()->break_on_next_function_call()) {
       DCHECK_EQ(isolate->debug_execution_mode(), DebugInfo::kBreakpoints);
       isolate->debug()->PrepareStepIn(fun);
     }
     if (isolate->debug_execution_mode() == DebugInfo::kSideEffects &&
         !isolate->debug()->PerformSideEffectCheck(fun, receiver)) {
-      return isolate->heap()->exception();
+      return ReadOnlyRoots(isolate).exception();
     }
   }
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 // Set one shot breakpoints for the suspended generator object.
@@ -1695,7 +622,7 @@ RUNTIME_FUNCTION(Runtime_DebugPrepareStepInSuspendedGenerator) {
   HandleScope scope(isolate);
   DCHECK_EQ(0, args.length());
   isolate->debug()->PrepareStepInSuspendedGenerator();
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 RUNTIME_FUNCTION(Runtime_DebugPushPromise) {
@@ -1703,7 +630,7 @@ RUNTIME_FUNCTION(Runtime_DebugPushPromise) {
   HandleScope scope(isolate);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, promise, 0);
   isolate->PushPromise(promise);
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 
@@ -1711,22 +638,7 @@ RUNTIME_FUNCTION(Runtime_DebugPopPromise) {
   DCHECK_EQ(0, args.length());
   SealHandleScope shs(isolate);
   isolate->PopPromise();
-  return isolate->heap()->undefined_value();
-}
-
-RUNTIME_FUNCTION(Runtime_DebugAsyncFunctionPromiseCreated) {
-  DCHECK_EQ(1, args.length());
-  HandleScope scope(isolate);
-  CONVERT_ARG_HANDLE_CHECKED(JSObject, promise, 0);
-  isolate->PushPromise(promise);
-  int id = isolate->debug()->NextAsyncTaskId(promise);
-  Handle<Symbol> async_stack_id_symbol =
-      isolate->factory()->promise_async_stack_id_symbol();
-  JSObject::SetProperty(promise, async_stack_id_symbol,
-                        handle(Smi::FromInt(id), isolate),
-                        LanguageMode::kStrict)
-      .Assert();
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 RUNTIME_FUNCTION(Runtime_DebugIsActive) {
@@ -1743,11 +655,11 @@ Handle<JSObject> MakeRangeObject(Isolate* isolate, const CoverageBlock& range) {
   Handle<String> count_string = factory->InternalizeUtf8String("count");
 
   Handle<JSObject> range_obj = factory->NewJSObjectWithNullProto();
-  JSObject::AddProperty(range_obj, start_string,
+  JSObject::AddProperty(isolate, range_obj, start_string,
                         factory->NewNumberFromInt(range.start), NONE);
-  JSObject::AddProperty(range_obj, end_string,
+  JSObject::AddProperty(isolate, range_obj, end_string,
                         factory->NewNumberFromInt(range.end), NONE);
-  JSObject::AddProperty(range_obj, count_string,
+  JSObject::AddProperty(isolate, range_obj, count_string,
                         factory->NewNumberFromUint(range.count), NONE);
 
   return range_obj;
@@ -1796,8 +708,8 @@ RUNTIME_FUNCTION(Runtime_DebugCollectCoverage) {
 
     Handle<JSArray> script_obj =
         factory->NewJSArrayWithElements(ranges_array, PACKED_ELEMENTS);
-    Handle<JSObject> wrapper = Script::GetWrapper(script_data.script);
-    JSObject::AddProperty(script_obj, script_string, wrapper, NONE);
+    JSObject::AddProperty(isolate, script_obj, script_string,
+                          handle(script_data.script->source(), isolate), NONE);
     scripts_array->set(i, *script_obj);
   }
   return *factory->NewJSArrayWithElements(scripts_array, PACKED_ELEMENTS);
@@ -1808,7 +720,7 @@ RUNTIME_FUNCTION(Runtime_DebugTogglePreciseCoverage) {
   CONVERT_BOOLEAN_ARG_CHECKED(enable, 0);
   Coverage::SelectMode(isolate, enable ? debug::Coverage::kPreciseCount
                                        : debug::Coverage::kBestEffort);
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 RUNTIME_FUNCTION(Runtime_DebugToggleBlockCoverage) {
@@ -1816,7 +728,7 @@ RUNTIME_FUNCTION(Runtime_DebugToggleBlockCoverage) {
   CONVERT_BOOLEAN_ARG_CHECKED(enable, 0);
   Coverage::SelectMode(isolate, enable ? debug::Coverage::kBlockCount
                                        : debug::Coverage::kBestEffort);
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
 RUNTIME_FUNCTION(Runtime_IncBlockCounter) {
@@ -1836,8 +748,67 @@ RUNTIME_FUNCTION(Runtime_IncBlockCounter) {
     coverage_info->IncrementBlockCount(coverage_array_slot_index);
   }
 
-  return isolate->heap()->undefined_value();
+  return ReadOnlyRoots(isolate).undefined_value();
 }
 
+RUNTIME_FUNCTION(Runtime_DebugAsyncFunctionSuspended) {
+  DCHECK_EQ(1, args.length());
+  HandleScope scope(isolate);
+  CONVERT_ARG_HANDLE_CHECKED(JSPromise, promise, 0);
+  isolate->OnAsyncFunctionStateChanged(promise, debug::kAsyncFunctionSuspended);
+  return ReadOnlyRoots(isolate).undefined_value();
+}
+
+RUNTIME_FUNCTION(Runtime_DebugAsyncFunctionFinished) {
+  DCHECK_EQ(2, args.length());
+  HandleScope scope(isolate);
+  CONVERT_BOOLEAN_ARG_CHECKED(has_suspend, 0);
+  CONVERT_ARG_HANDLE_CHECKED(JSPromise, promise, 1);
+  isolate->PopPromise();
+  if (has_suspend) {
+    isolate->OnAsyncFunctionStateChanged(promise,
+                                         debug::kAsyncFunctionFinished);
+  }
+  return ReadOnlyRoots(isolate).undefined_value();
+}
+
+RUNTIME_FUNCTION(Runtime_LiveEditPatchScript) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(JSFunction, script_function, 0);
+  CONVERT_ARG_HANDLE_CHECKED(String, new_source, 1);
+
+  Handle<Script> script(Script::cast(script_function->shared()->script()),
+                        isolate);
+  v8::debug::LiveEditResult result;
+  LiveEdit::PatchScript(isolate, script, new_source, false, &result);
+  switch (result.status) {
+    case v8::debug::LiveEditResult::COMPILE_ERROR:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: COMPILE_ERROR"));
+    case v8::debug::LiveEditResult::BLOCKED_BY_RUNNING_GENERATOR:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: BLOCKED_BY_RUNNING_GENERATOR"));
+    case v8::debug::LiveEditResult::BLOCKED_BY_FUNCTION_ABOVE_BREAK_FRAME:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: BLOCKED_BY_FUNCTION_ABOVE_BREAK_FRAME"));
+    case v8::debug::LiveEditResult::
+        BLOCKED_BY_FUNCTION_BELOW_NON_DROPPABLE_FRAME:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: BLOCKED_BY_FUNCTION_BELOW_NON_DROPPABLE_FRAME"));
+    case v8::debug::LiveEditResult::BLOCKED_BY_ACTIVE_FUNCTION:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: BLOCKED_BY_ACTIVE_FUNCTION"));
+    case v8::debug::LiveEditResult::BLOCKED_BY_NEW_TARGET_IN_RESTART_FRAME:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: BLOCKED_BY_NEW_TARGET_IN_RESTART_FRAME"));
+    case v8::debug::LiveEditResult::FRAME_RESTART_IS_NOT_SUPPORTED:
+      return isolate->Throw(*isolate->factory()->NewStringFromAsciiChecked(
+          "LiveEdit failed: FRAME_RESTART_IS_NOT_SUPPORTED"));
+    case v8::debug::LiveEditResult::OK:
+      return ReadOnlyRoots(isolate).undefined_value();
+  }
+  return ReadOnlyRoots(isolate).undefined_value();
+}
 }  // namespace internal
 }  // namespace v8