Revert "Revert "Null check elimination improvement""

This reverts commit 31aa97cfec5ee76b2f2496464e1b6f9e11d21a29.

..and thereby brings back change 380165, which was reverted
because it was buggy.

Three problems with the original CL:

  1.  The author ran the pre-submit tests, but used -j24 and
      failed to search the output for fail messages.
  2.  The new null check analysis pass uses an interative
      approach to identify whether a null check is needed.  It
      is possible that the null-check-required state may
      oscillate, and a logic error caused it to stick in the
      "no check needed" state.
  3.  Our old nemesis Dalvik untyped constants, in which 0 values
      can be used both as object reference and non-object references.
      This CL conservatively treats all CONST definitions as
      potential object definitions for the purposes of null
      check elimination.

Change-Id: I3c1744e44318276e42989502a314585e56ac57a0
diff --git a/compiler/dex/quick/codegen_util.cc b/compiler/dex/quick/codegen_util.cc
index a6653fa..dfbc887 100644
--- a/compiler/dex/quick/codegen_util.cc
+++ b/compiler/dex/quick/codegen_util.cc
@@ -164,7 +164,8 @@
          lir->operands[0] = WrapPointer(ArenaStrdup("No instruction string"));
       }
       LOG(INFO) << "-------- dalvik offset: 0x" << std::hex
-                << lir->dalvik_offset << " @ " << reinterpret_cast<char*>(lir->operands[0]);
+                << lir->dalvik_offset << " @ "
+                << reinterpret_cast<char*>(UnwrapPointer(lir->operands[0]));
       break;
     case kPseudoExitBlock:
       LOG(INFO) << "-------- exit offset: 0x" << std::hex << dest;