[debug][api] Move debugger support to debug-interface.cc.

Previously we had the debugger / inspector support declared in
debug-interface.h, but the implementation was sprinkled all across
api.cc, which was quite messy. This moves the relevant macros and
other bits into api-macros.h (with api-macros-undef.h to support
jumbo builds), and moves the debugger interface implementation to
src/debug/debug-interface.cc.

Bug: chromium:1162229
Change-Id: I6965ebf2301459c89e3217bd87396ec353d814e9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2653154
Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72392}

BUILD.gn

@@ -2463,6 +2463,8 @@ v8_source_set("v8_base_without_compiler") {
     "src/api/api-arguments-inl.h",
     "src/api/api-arguments.cc",
     "src/api/api-arguments.h",
+    "src/api/api-inl.h",
+    "src/api/api-macros.h",
     "src/api/api-natives.cc",
     "src/api/api-natives.h",
     "src/api/api.cc",
@@ -2627,6 +2629,7 @@ v8_source_set("v8_base_without_compiler") {
     "src/debug/debug-evaluate.h",
     "src/debug/debug-frames.cc",
     "src/debug/debug-frames.h",
+    "src/debug/debug-interface.cc",
     "src/debug/debug-interface.h",
     "src/debug/debug-property-iterator.cc",
     "src/debug/debug-property-iterator.h",

PRESUBMIT.py

@@ -480,8 +480,8 @@ def _CheckNoexceptAnnotations(input_api, output_api):
   def FilterFile(affected_file):
     return input_api.FilterSourceFile(
         affected_file,
-        files_to_check=(r'src/.*', r'test/.*'))
+        files_to_check=(r'src/.*', r'test/.*'),
-
+        files_to_skip=(r'src[\\\/]api[\\\/]api\.cc'))
 
   # matches any class name.
   class_name = r'\b([A-Z][A-Za-z0-9_:]*)(?:::\1)?'

src/api/api-inl.h

@@ -6,6 +6,7 @@
 #define V8_API_API_INL_H_
 
 #include "src/api/api.h"
+#include "src/execution/microtask-queue.h"
 #include "src/handles/handles-inl.h"
 #include "src/objects/foreign-inl.h"
 #include "src/objects/js-weak-refs.h"
@@ -131,6 +132,111 @@ OPEN_HANDLE_LIST(MAKE_OPEN_HANDLE)
 #undef MAKE_OPEN_HANDLE
 #undef OPEN_HANDLE_LIST
 
+template <bool do_callback>
+class V8_NODISCARD CallDepthScope {
+ public:
+  CallDepthScope(i::Isolate* isolate, Local<Context> context)
+      : isolate_(isolate),
+        context_(context),
+        escaped_(false),
+        safe_for_termination_(isolate->next_v8_call_is_safe_for_termination()),
+        interrupts_scope_(isolate_, i::StackGuard::TERMINATE_EXECUTION,
+                          isolate_->only_terminate_in_safe_scope()
+                              ? (safe_for_termination_
+                                     ? i::InterruptsScope::kRunInterrupts
+                                     : i::InterruptsScope::kPostponeInterrupts)
+                              : i::InterruptsScope::kNoop) {
+    isolate_->thread_local_top()->IncrementCallDepth(this);
+    isolate_->set_next_v8_call_is_safe_for_termination(false);
+    if (!context.IsEmpty()) {
+      i::Handle<i::Context> env = Utils::OpenHandle(*context);
+      i::HandleScopeImplementer* impl = isolate->handle_scope_implementer();
+      if (!isolate->context().is_null() &&
+          isolate->context().native_context() == env->native_context()) {
+        context_ = Local<Context>();
+      } else {
+        impl->SaveContext(isolate->context());
+        isolate->set_context(*env);
+      }
+    }
+    if (do_callback) isolate_->FireBeforeCallEnteredCallback();
+  }
+  ~CallDepthScope() {
+    i::MicrotaskQueue* microtask_queue = isolate_->default_microtask_queue();
+    if (!context_.IsEmpty()) {
+      i::HandleScopeImplementer* impl = isolate_->handle_scope_implementer();
+      isolate_->set_context(impl->RestoreContext());
+
+      i::Handle<i::Context> env = Utils::OpenHandle(*context_);
+      microtask_queue = env->native_context().microtask_queue();
+    }
+    if (!escaped_) isolate_->thread_local_top()->DecrementCallDepth(this);
+    if (do_callback) isolate_->FireCallCompletedCallback(microtask_queue);
+// TODO(jochen): This should be #ifdef DEBUG
+#ifdef V8_CHECK_MICROTASKS_SCOPES_CONSISTENCY
+    if (do_callback) {
+      if (microtask_queue && microtask_queue->microtasks_policy() ==
+                                 v8::MicrotasksPolicy::kScoped) {
+        DCHECK(microtask_queue->GetMicrotasksScopeDepth() ||
+               !microtask_queue->DebugMicrotasksScopeDepthIsZero());
+      }
+    }
+#endif
+    DCHECK(CheckKeptObjectsClearedAfterMicrotaskCheckpoint(microtask_queue));
+    isolate_->set_next_v8_call_is_safe_for_termination(safe_for_termination_);
+  }
+
+  CallDepthScope(const CallDepthScope&) = delete;
+  CallDepthScope& operator=(const CallDepthScope&) = delete;
+
+  void Escape() {
+    DCHECK(!escaped_);
+    escaped_ = true;
+    auto thread_local_top = isolate_->thread_local_top();
+    thread_local_top->DecrementCallDepth(this);
+    bool clear_exception = thread_local_top->CallDepthIsZero() &&
+                           thread_local_top->try_catch_handler_ == nullptr;
+    isolate_->OptionalRescheduleException(clear_exception);
+  }
+
+ private:
+  bool CheckKeptObjectsClearedAfterMicrotaskCheckpoint(
+      i::MicrotaskQueue* microtask_queue) {
+    bool did_perform_microtask_checkpoint =
+        isolate_->thread_local_top()->CallDepthIsZero() && do_callback &&
+        microtask_queue &&
+        microtask_queue->microtasks_policy() == MicrotasksPolicy::kAuto;
+    return !did_perform_microtask_checkpoint ||
+           isolate_->heap()->weak_refs_keep_during_job().IsUndefined(isolate_);
+  }
+
+  i::Isolate* const isolate_;
+  Local<Context> context_;
+  bool escaped_;
+  bool do_callback_;
+  bool safe_for_termination_;
+  i::InterruptsScope interrupts_scope_;
+  i::Address previous_stack_height_;
+
+  friend class i::ThreadLocalTop;
+
+  DISALLOW_NEW_AND_DELETE()
+};
+
+class V8_NODISCARD InternalEscapableScope : public EscapableHandleScope {
+ public:
+  explicit inline InternalEscapableScope(i::Isolate* isolate)
+      : EscapableHandleScope(reinterpret_cast<v8::Isolate*>(isolate)) {}
+};
+
+inline bool IsExecutionTerminatingCheck(i::Isolate* isolate) {
+  if (isolate->has_scheduled_exception()) {
+    return isolate->scheduled_exception() ==
+           i::ReadOnlyRoots(isolate).termination_exception();
+  }
+  return false;
+}
+
 namespace internal {
 
 Handle<Context> HandleScopeImplementer::LastEnteredContext() {

src/api/api-macros-undef.h

@@ -0,0 +1,20 @@
+// Copyright 2021 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// PRESUBMIT_INTENTIONALLY_MISSING_INCLUDE_GUARD
+
+#undef LOG_API
+#undef ENTER_V8_DO_NOT_USE
+#undef ENTER_V8_HELPER_DO_NOT_USE
+#undef PREPARE_FOR_DEBUG_INTERFACE_EXECUTION_WITH_ISOLATE
+#undef PREPARE_FOR_EXECUTION_WITH_CONTEXT
+#undef PREPARE_FOR_EXECUTION
+#undef ENTER_V8
+#undef ENTER_V8_NO_SCRIPT
+#undef ENTER_V8_NO_SCRIPT_NO_EXCEPTION
+#undef ENTER_V8_FOR_NEW_CONTEXT
+#undef EXCEPTION_BAILOUT_CHECK_SCOPED_DO_NOT_USE
+#undef RETURN_ON_FAILED_EXECUTION
+#undef RETURN_ON_FAILED_EXECUTION_PRIMITIVE
+#undef RETURN_ESCAPED

src/api/api-macros.h

@@ -0,0 +1,132 @@
+// Copyright 2021 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Note 1: Any file that includes this one should include api-macros-undef.h
+// at the bottom.
+
+// Note 2: This file is deliberately missing the include guards (the undeffing
+// approach wouldn't work otherwise).
+//
+// PRESUBMIT_INTENTIONALLY_MISSING_INCLUDE_GUARD
+
+/*
+ * Most API methods should use one of the three macros:
+ *
+ * ENTER_V8, ENTER_V8_NO_SCRIPT, ENTER_V8_NO_SCRIPT_NO_EXCEPTION.
+ *
+ * The latter two assume that no script is executed, and no exceptions are
+ * scheduled in addition (respectively). Creating a pending exception and
+ * removing it before returning is ok.
+ *
+ * Exceptions should be handled either by invoking one of the
+ * RETURN_ON_FAILED_EXECUTION* macros.
+ *
+ * Don't use macros with DO_NOT_USE in their name.
+ *
+ * TODO(jochen): Document debugger specific macros.
+ * TODO(jochen): Document LOG_API and other RuntimeCallStats macros.
+ * TODO(jochen): All API methods should invoke one of the ENTER_V8* macros.
+ * TODO(jochen): Remove calls form API methods to DO_NOT_USE macros.
+ */
+
+#define LOG_API(isolate, class_name, function_name)                           \
+  i::RuntimeCallTimerScope _runtime_timer(                                    \
+      isolate, i::RuntimeCallCounterId::kAPI_##class_name##_##function_name); \
+  LOG(isolate, ApiEntryCall("v8::" #class_name "::" #function_name))
+
+#define ENTER_V8_DO_NOT_USE(isolate) i::VMState<v8::OTHER> __state__((isolate))
+
+#define ENTER_V8_HELPER_DO_NOT_USE(isolate, context, class_name,  \
+                                   function_name, bailout_value,  \
+                                   HandleScopeClass, do_callback) \
+  if (IsExecutionTerminatingCheck(isolate)) {                     \
+    return bailout_value;                                         \
+  }                                                               \
+  HandleScopeClass handle_scope(isolate);                         \
+  CallDepthScope<do_callback> call_depth_scope(isolate, context); \
+  LOG_API(isolate, class_name, function_name);                    \
+  i::VMState<v8::OTHER> __state__((isolate));                     \
+  bool has_pending_exception = false
+
+#define PREPARE_FOR_DEBUG_INTERFACE_EXECUTION_WITH_ISOLATE(isolate, T)       \
+  if (IsExecutionTerminatingCheck(isolate)) {                                \
+    return MaybeLocal<T>();                                                  \
+  }                                                                          \
+  InternalEscapableScope handle_scope(isolate);                              \
+  CallDepthScope<false> call_depth_scope(isolate, v8::Local<v8::Context>()); \
+  i::VMState<v8::OTHER> __state__((isolate));                                \
+  bool has_pending_exception = false
+
+#define PREPARE_FOR_EXECUTION_WITH_CONTEXT(context, class_name, function_name, \
+                                           bailout_value, HandleScopeClass,    \
+                                           do_callback)                        \
+  auto isolate = context.IsEmpty()                                             \
+                     ? i::Isolate::Current()                                   \
+                     : reinterpret_cast<i::Isolate*>(context->GetIsolate());   \
+  ENTER_V8_HELPER_DO_NOT_USE(isolate, context, class_name, function_name,      \
+                             bailout_value, HandleScopeClass, do_callback);
+
+#define PREPARE_FOR_EXECUTION(context, class_name, function_name, T)          \
+  PREPARE_FOR_EXECUTION_WITH_CONTEXT(context, class_name, function_name,      \
+                                     MaybeLocal<T>(), InternalEscapableScope, \
+                                     false)
+
+#define ENTER_V8(isolate, context, class_name, function_name, bailout_value, \
+                 HandleScopeClass)                                           \
+  ENTER_V8_HELPER_DO_NOT_USE(isolate, context, class_name, function_name,    \
+                             bailout_value, HandleScopeClass, true)
+
+#ifdef DEBUG
+#define ENTER_V8_NO_SCRIPT(isolate, context, class_name, function_name,   \
+                           bailout_value, HandleScopeClass)               \
+  ENTER_V8_HELPER_DO_NOT_USE(isolate, context, class_name, function_name, \
+                             bailout_value, HandleScopeClass, false);     \
+  i::DisallowJavascriptExecutionDebugOnly __no_script__((isolate))
+
+// Lightweight version for APIs that don't require an active context.
+#define ASSERT_NO_SCRIPT_NO_EXCEPTION(isolate)                      \
+  i::DisallowJavascriptExecutionDebugOnly __no_script__((isolate)); \
+  i::DisallowExceptions __no_exceptions__((isolate))
+
+#define ENTER_V8_NO_SCRIPT_NO_EXCEPTION(isolate) \
+  i::VMState<v8::OTHER> __state__((isolate));    \
+  ASSERT_NO_SCRIPT_NO_EXCEPTION(isolate)
+
+#define ENTER_V8_FOR_NEW_CONTEXT(isolate)     \
+  i::VMState<v8::OTHER> __state__((isolate)); \
+  i::DisallowExceptions __no_exceptions__((isolate))
+#else
+#define ENTER_V8_NO_SCRIPT(isolate, context, class_name, function_name,   \
+                           bailout_value, HandleScopeClass)               \
+  ENTER_V8_HELPER_DO_NOT_USE(isolate, context, class_name, function_name, \
+                             bailout_value, HandleScopeClass, false)
+
+#define ASSERT_NO_SCRIPT_NO_EXCEPTION(isolate)
+
+#define ENTER_V8_NO_SCRIPT_NO_EXCEPTION(isolate) \
+  i::VMState<v8::OTHER> __state__((isolate));
+
+#define ENTER_V8_FOR_NEW_CONTEXT(isolate) \
+  i::VMState<v8::OTHER> __state__((isolate));
+#endif  // DEBUG
+
+#define EXCEPTION_BAILOUT_CHECK_SCOPED_DO_NOT_USE(isolate, value) \
+  do {                                                            \
+    if (has_pending_exception) {                                  \
+      call_depth_scope.Escape();                                  \
+      return value;                                               \
+    }                                                             \
+  } while (false)
+
+#define RETURN_ON_FAILED_EXECUTION(T) \
+  EXCEPTION_BAILOUT_CHECK_SCOPED_DO_NOT_USE(isolate, MaybeLocal<T>())
+
+#define RETURN_ON_FAILED_EXECUTION_PRIMITIVE(T) \
+  EXCEPTION_BAILOUT_CHECK_SCOPED_DO_NOT_USE(isolate, Nothing<T>())
+
+#define RETURN_ESCAPED(value) return handle_scope.Escape(value);
+
+// TODO(jochen): This should be #ifdef DEBUG
+#ifdef V8_CHECK_MICROTASKS_SCOPES_CONSISTENCY
+#endif