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

src/lithium.cc

Index: src/lithium.cc
===================================================================
--- src/lithium.cc	(revision 13212)
+++ src/lithium.cc	(working copy)
@@ -416,6 +416,12 @@
 
 Handle<Code> LChunk::Codegen() {
   MacroAssembler assembler(info()->isolate(), NULL, 0);
+  if (FLAG_jit_profile) {
+    JITCodeLineInfo* lineinfo = assembler.positions_recorder()->
+                                          InitializeJITLineInfo();

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

nit: indentation after line break, better yet break after "=" and indent line by
4. 

+    LOG_CODE_EVENT(info()->isolate(),
+                   CodeStartLinePosInfoRecordEvent(lineinfo));
+  }
   LCodeGen generator(this, &assembler, info());
 
   MarkEmptyBlocks();
@@ -429,11 +435,18 @@
     Handle<Code> code =
         CodeGenerator::MakeCodeEpilogue(&assembler, flags, info());
     generator.FinishCode(code);
+
+    if (FLAG_jit_profile) {
+      if (!code.is_null()) {
+        void* lineinfo = assembler.positions_recorder()->DetachJITLineInfo();
+        LOG_CODE_EVENT(info()->isolate(),
+                       CodeEndLinePosInfoRecordEvent(*code, lineinfo));
+      }
+    }
     CodeGenerator::PrintCode(code, info());
     return code;
   }
   return Handle<Code>::null();
 }
 
-

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

nit: unrelated whitespace change

 } }  // namespace v8::internal