This patch is the propagation version of https://codereview.chromium.org/10824032 patch

include/v8.h

Index: include/v8.h
===================================================================
--- include/v8.h	(revision 13212)
+++ include/v8.h	(working copy)
@@ -3021,7 +3021,6 @@
 typedef void (*FunctionEntryHook)(uintptr_t function,
                                   uintptr_t return_addr_location);
 
-

[danno, 2012/12/20 16:27:20]

nit: Please don't remove whitespace not in accordance with our coding style,
which is 2 lines between declarations/functions/etc.

 /**
  * A JIT code event is issued each time code is added, moved or removed.
  *
@@ -3031,7 +3030,10 @@
   enum EventType {
     CODE_ADDED,
     CODE_MOVED,
-    CODE_REMOVED
+    CODE_REMOVED,
+    CODE_ADD_LINE_POS_INFO,
+    CODE_START_LINE_INFO_RECORDING,
+    CODE_END_LINE_INFO_RECORDING
   };
 
   // Type of event.
@@ -3040,6 +3042,9 @@
   void* code_start;
   // Size of the instructions.
   size_t code_len;
+  // It can be Script info for CODE_ADDDED event or line_info_struct

[danno, 2012/12/20 16:27:20]

How about removing the "It can be", and only two DDs in ADDED

+  // for CODE_ADD_LINE_POS_INFO and CODE_END_LINE_INFO_RECORDING event
+  void* userdata;

[danno, 2012/12/20 16:27:20]

user_data is probably better. Also, why not have two fields that are strongly
typed for CODE_ADDED and CODE_ADD_LINE_POS_INFO/CODE_END_LINE_INFO_RECORDING
rather than this single void*?

 
   union {
     // Only valid for CODE_ADDED.
@@ -3050,6 +3055,17 @@
       // Number of chars in str.
       size_t len;
     } name;
+
+    // Only valid for CODE_ADD_LINE_INFO

[danno, 2012/12/20 16:27:20]

CODE_ADD_LINE_POS_INFO

+    struct {
+      // PC offset
+      unsigned offset;

[danno, 2012/12/20 16:27:20]

Why use unsigned rather than a size_t? This seems more consistent with the rest
of the API.

+      // Code postion
+      unsigned pos;

[danno, 2012/12/20 16:27:20]

Same here

+      // Whether this position is statement

[danno, 2012/12/20 16:27:20]

How about you clarify what it is if it isn't a statement, e.g. "Indicates
whether this position is a statement (as opposed to a XXXX)" 

+      bool is_statement;
+    } line_info;
+
     // New location of instructions. Only valid for CODE_MOVED.
     void* new_code_start;
   };