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

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
===================================================================
--- src/ia32/lithium-codegen-ia32.cc	(revision 13212)
+++ src/ia32/lithium-codegen-ia32.cc	(working copy)
@@ -320,6 +320,13 @@
       }
       instr->CompileToNative(this);
     }
+
+    if (instr->HasPointerMap()) {

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

Why do you need to add this? I would think that this duplicates a lot of
position information for instructions that already output position information,
and don't understand the motivation behind the change. And if you do make this
change, you need to make it for ARM as well.

+      LPointerMap* pointers = instr->pointer_map();
+      if (pointers->position() != RelocInfo::kNoPosition) {
+        RecordPosition(pointers->position());
+      }
+    }
   }
   EnsureSpaceForLazyDeopt();
   return !is_aborted();