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

src/lithium.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 398 matching lines @@
     info->set_bailout_reason("not enough virtual registers (regalloc)");
     return NULL;
   }
 
   return chunk;
 }
 
 
 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();
 
   if (generator.GenerateCode()) {
     if (FLAG_trace_codegen) {
       PrintF("Crankshaft Compiler - ");
     }
     CodeGenerator::MakeCodePrologue(info());
     Code::Flags flags = Code::ComputeFlags(Code::OPTIMIZED_FUNCTION);
     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