[wasm] Make wasm info available on the stack trace

include/v8.h

 // Copyright 2012 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.
 
 /** \mainpage V8 API Reference Guide
  *
  * V8 is Google's open source JavaScript engine.
  *
  * This set of documents provides reference material generated from the
  * V8 header file, include/v8.h.
@@ skipping 1510 matching lines @@
    */
   bool IsSharedCrossOrigin() const;
   bool IsOpaque() const;
 
   // TODO(1245381): Print to a string instead of on a FILE.
   static void PrintCurrentStackTrace(Isolate* isolate, FILE* out);
 
   static const int kNoLineNumberInfo = 0;
   static const int kNoColumnInfo = 0;
   static const int kNoScriptIdInfo = 0;
+  static const uint32_t kNoWasmByteOffsetInfo = static_cast<uint32_t>(-1);
 };
 
 
 /**
  * Representation of a JavaScript stack trace. The information collected is a
  * snapshot of the execution stack and the information remains valid after
  * execution continues.
  */
 class V8_EXPORT StackTrace {
  public:
   /**
    * Flags that determine what information is placed captured for each
    * StackFrame when grabbing the current stack trace.
    */
   enum StackTraceOptions {
     kLineNumber = 1,
     kColumnOffset = 1 << 1 | kLineNumber,
     kScriptName = 1 << 2,
     kFunctionName = 1 << 3,
     kIsEval = 1 << 4,
     kIsConstructor = 1 << 5,
     kScriptNameOrSourceURL = 1 << 6,
     kScriptId = 1 << 7,
     kExposeFramesAcrossSecurityOrigins = 1 << 8,
-    kOverview = kLineNumber | kColumnOffset | kScriptName | kFunctionName,
+    kIsWasm = 1 << 9,
+    kWasmByteOffset = 1 << 10,
+    kWasmObject = 1 << 11,
+    kOverview = kLineNumber | kColumnOffset | kScriptName | kFunctionName |
+                kIsWasm | kWasmByteOffset | kWasmObject,
     kDetailed = kOverview | kIsEval | kIsConstructor | kScriptNameOrSourceURL
   };
 
   /**
    * Returns a StackFrame at a particular index.
    */
   Local<StackFrame> GetFrame(uint32_t index) const;
 
   /**
    * Returns the number of StackFrames.
@@ skipping 72 matching lines @@
    * Returns whether or not the associated function is compiled via a call to
    * eval().
    */
   bool IsEval() const;
 
   /**
    * Returns whether or not the associated function is called as a
    * constructor via "new".
    */
   bool IsConstructor() const;
+
+  /**

[Yang, 2016/04/28 13:08:43]

Why do we need these three methods? What changes are planned on blink's side? I
don't think this is necessary to make the current stack trace mechanism work, is
it?

+   * Returns whether or not the associated function is a wasm function.
+   * Always returns false if kIsWasm was not passed as an option when capturing
+   * the StackTrace.
+   */
+  bool IsWasm() const;
+
+  /**
+   * Returns the wasm object, or undefined if the associated function of the
+   * frame is no wasm function or if kWasmObject was not passed as an option
+   * when capturing the StackTrace.
+   */
+  Local<Object> GetWasmObject() const;
+
+  /**
+   * Returns the byte offset in the associated wasm function, or
+   * Message::kNoWasmByteOffsetInfo if the associated function of the frame is

[Yang, 2016/04/28 13:08:43]

Can we just crash with a check failure if the function is not wasm? The embedder
should be responsible to check IsWasm() upfront.

+   * no wasm function.
+   */
+  uint32_t GetWasmByteOffset() const;
 };
 
 
 // A StateTag represents a possible state of the VM.
 enum StateTag { JS, GC, COMPILER, OTHER, EXTERNAL, IDLE };
 
 
 // A RegisterState represents the current state of registers used
 // by the sampling profiler API.
 struct RegisterState {
@@ skipping 7116 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // INCLUDE_V8_H_