[wasm] Make wasm info available on the stack trace

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 83b777d30948104bec43ba3c9926cd68ff637690..cc92a63943d43fdf8d8ab8677ab760ceebda1eb6 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -1528,6 +1528,7 @@ class V8_EXPORT Message {
   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);
 };
 
 
@@ -1552,7 +1553,11 @@ class V8_EXPORT StackTrace {
     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
   };
 
@@ -1645,6 +1650,27 @@ class V8_EXPORT StackFrame {
    * 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;
 };