[inspector] Introduce translation of wasm frames

src/inspector/wasm-translation.h

+// Copyright 2016 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.
+
+#ifndef V8_INSPECTOR_WASMTRANSLATION_H_
+#define V8_INSPECTOR_WASMTRANSLATION_H_
+
+#include <unordered_map>
+
+#include "include/v8.h"
+#include "src/base/macros.h"
+#include "src/inspector/string-16.h"
+
+namespace v8_inspector {
+
+// Forward declarations.
+class V8Debugger;
+class V8DebuggerScript;
+struct ScriptBreakpoint;
+namespace protocol {
+namespace Debugger {
+class Location;
+}
+}
+
+class WasmTranslation {
+ public:
+  enum Mode { Raw, Disassemble };
+
+  WasmTranslation(v8::Isolate* isolate, V8Debugger* debugger);
+  ~WasmTranslation();
+
+  // Set translation mode.
+  void SetMode(Mode mode) { mode_ = mode; }
+
+  // Make a wasm script known to the translation. Only locations referencing a
+  // registered script will be translated by the Translate functions below.
+  void AddScript(v8::Local<v8::Object> script_wrapper);
+
+  // Clear all registered scripts.
+  void Clear();
+
+  // Translate a location as generated by V8 to a location that should be sent
+  // over protocol.
+  // Does nothing for locations referencing a script which was not registered
+  // before via AddScript.
+  // Line and column are 0-based.
+  // The context group id specifies the context of the script.
+  // If the script was registered and the respective wasm function was not seen
+  // before, a new artificial script representing this function will be created
+  // and made public to the frontend.
+  // Returns true if the location was translated, false otherwise.
+  bool TranslateWasmScriptLocationToProtocolLocation(String16* script_id,
+                                                     int* line_number,
+                                                     int* column_number,
+                                                     int context_group_id);
+
+  // Translate back from protocol locations (potentially referencing artificial
+  // scripts for individual wasm functions) to locations that make sense to V8.
+  // Does nothing if the location was not generated by the translate method
+  // above.
+  // Returns true if the location was translated, false otherwise.
+  bool TranslateProtocolLocationToWasmScriptLocation(String16* script_id,
+                                                     int* line_number,
+                                                     int* column_number);
+
+ private:
+  class TranslatorImpl;
+  friend class TranslatorImpl;
+
+  void AddFakeScript(std::unique_ptr<V8DebuggerScript> fake_script,
+                     TranslatorImpl* translator, int context_group_id);
+
+  v8::Isolate* isolate_;
+  V8Debugger* debugger_;
+  std::unordered_map<int, std::unique_ptr<TranslatorImpl>> wasm_translators_;
+  std::unordered_map<String16, TranslatorImpl*> fake_scripts_;
+  Mode mode_;
+
+  DISALLOW_COPY_AND_ASSIGN(WasmTranslation);
+};
+
+}  // namespace v8_inspector
+
+#endif  // V8_INSPECTOR_WASMTRANSLATION_H_